The neoclassical theory of growth and distribution

Directory of Open Access Journals (Sweden)

Robert M. Solow

2000-12-01

Full Text Available The paper surveys the neoclassical theory of growth. As a preliminary, the meaning of the adjective "neoclassical" is discussed. The basic model is then sketched, and the conditions ensuring a stationary state are illustrated. The issue of the convergence to a stationary state (and that of the speed of convergence is further considered. A discussion of "primary factors" opens the way to the "new" theory of growth, with endogenous technical progress. A number of extensions of the basic model are then recalled: two-sector and multi-sectoral models, overlapping generations models, the role of money in growth models.

Endogenous versus Exogenous Growth Factor Regulation of Articular Chondrocytes

Science.gov (United States)

Shi, Shuiliang; Chan, Albert G.; Mercer, Scott; Eckert, George J.; Trippel, Stephen B.

2014-01-01

Anabolic growth factors that regulate the function of articular chondrocytes are candidates for articular cartilage repair. Such factors may be delivered by pharmacotherapy in the form of exogenous proteins, or by gene therapy as endogenous proteins. It is unknown whether delivery method influences growth factor effectiveness in regulating articular chondrocyte reparative functions. We treated adult bovine articular chondrocytes with exogenous recombinant insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-β1), or with the genes encoding these growth factors for endogenous production. Treatment effects were measured as change in chondrocyte DNA content, glycosaminoglycan production, and aggrecan gene expression. We found that IGF-I stimulated chondrocyte biosynthesis similarly when delivered by either exogenous or endogenous means. In contrast, exogenous TGF-ß1 stimulated these reparative functions, while endogenous TGF-ß1 had little effect. Endogenous TGF-ß1 became more bioactive following activation of the transgene protein product. These data indicate that effective mechanisms of growth factor delivery for articular cartilage repair may differ for different growth factors. In the case of IGF-I, gene therapy or protein therapy appear to be viable options. In contrast, TGF-ß1 gene therapy may be constrained by a limited ability of chondrocytes to convert latent complexes to an active form. PMID:24105960

Endogenous growth and economic capacity: Theory and empirical evidence for the NAFTA countries

Directory of Open Access Journals (Sweden)

Ignacio Perrotini-Hernàndez

2017-09-01

Full Text Available he paper sheds light on the relevance of economic capacity utilisation, capital accumulation and effective demand for the endogeneity of the natural growth rate with respect to normal, depressive and expansive growth regimes. Apart from contributing to fill this theoretical gap, a new model is developed for estimating the elasticity of the natural growth rate, with a specific focus on Canada, Mexico and the United States, throughout the pre-NAFTA and post-NAFTA periods. It is shown that growth regimes are related to the utilisation of economic capacity, while the elasticities of the expansive and depressive natural rates of growth vis-à-vis the normal rate are related to effective demand. It is also found that the normal, depressive and expansive natural rates of growth decreased since the inception of NAFTA, due to the concomitant decline in the growth rate of economic capacity. JEL Classification: O47, O51, O54

Horizontalists, verticalists, and structuralists: The theory of endogenous money reassessed

OpenAIRE

Palley, Thomas I.

2013-01-01

This paper uses the occasion of the twenty-fifth anniversary of Basil Moore’s book, Horizontalists and Verticalists, to reassess the theory of endogenous money. The paper distinguishes between horizontalists, verticalists, and structuralists. It argues Moore’s horizontalist representation of endogenous money was an over-simplification that discarded important enduring insights from monetary theory. The structuralist approach to endogenous money retains the basic insight that the money supply ...

Endogenous versus exogenous growth factor regulation of articular chondrocytes.

Science.gov (United States)

Shi, Shuiliang; Chan, Albert G; Mercer, Scott; Eckert, George J; Trippel, Stephen B

2014-01-01

Anabolic growth factors that regulate the function of articular chondrocytes are candidates for articular cartilage repair. Such factors may be delivered by pharmacotherapy in the form of exogenous proteins, or by gene therapy as endogenous proteins. It is unknown whether delivery method influences growth factor effectiveness in regulating articular chondrocyte reparative functions. We treated adult bovine articular chondrocytes with exogenous recombinant insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-β1), or with the genes encoding these growth factors for endogenous production. Treatment effects were measured as change in chondrocyte DNA content, glycosaminoglycan production, and aggrecan gene expression. We found that IGF-I stimulated chondrocyte biosynthesis similarly when delivered by either exogenous or endogenous means. In contrast, exogenous TGF-β1 stimulated these reparative functions, while endogenous TGF-β1 had little effect. Endogenous TGF-β1 became more bioactive following activation of the transgene protein product. These data indicate that effective mechanisms of growth factor delivery for articular cartilage repair may differ for different growth factors. In the case of IGF-I, gene therapy or protein therapy appear to be viable options. In contrast, TGF-β1 gene therapy may be constrained by a limited ability of chondrocytes to convert latent complexes to an active form. Published 2013 by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. This article is a U.S. Government work and is in the public domain in the USA.

Animal spirits, competitive markets, and endogenous growth

Science.gov (United States)

Miyazaki, Kenji

2013-10-01

This paper uses a simple model with an endogenous discount rate and linear technology to investigate whether a competitive equilibrium has a higher balanced growth path (BGP) than the social planning solution and whether the BGP is determinate or indeterminate. The implications are as follows. To start with, people with an instinct to compare themselves with others possess an endogenous discount rate. In turn, this instinct affects the economic growth rate in a competitive market economy. The competitive market economy also sometimes achieves higher economic growth than a social planning economy. However, the outcomes of market economy occasionally fluctuate because of the presence of the self-fulfilling prophecy or animal spirits.

Endogenous CO2 may inhibit bacterial growth and induce virulence gene expression in enteropathogenic Escherichia coli.

Science.gov (United States)

Martínez, Haydee; Buhse, Thomas; Rivera, Marco; Parmananda, P; Ayala, Guadalupe; Sánchez, Joaquín

2012-07-01

Analysis of the growth kinetics of enteropathogenic Escherichia coli (EPEC) revealed that growth was directly proportional to the ratio between the exposed surface area and the liquid culture volume (SA/V). It was hypothesized that this bacterial behavior was caused by the accumulation of an endogenous volatile growth inhibitor metabolite whose escape from the medium directly depended on the SA/V. The results of this work support the theory that an inhibitor is produced and indicate that it is CO(2). We also report that concomitant to the accumulation of CO(2), there is secretion of the virulence-related EspB and EspC proteins from EPEC. We therefore postulate that endogenous CO(2) may have an effect on both bacterial growth and virulence. Copyright © 2012 Elsevier Ltd. All rights reserved.

Endogenous Growth, Monetary Shocks and Nominal Rigidities

OpenAIRE

Annicchiarico, Barbara; Pelloni, Alessandra; Lorenza, Rossi

2010-01-01

We introduce endogenous growth in an otherwise standard NK model with staggered prices and wages. Some results follow: (i) monetary volatility negatively affects long-run growth; (ii) the relation between nominal volatility and growth depends on the persistence of the nominal shocks and on the Taylor rule considered; (iii) a Taylor rule with smoothing increases the negative effect of nominal volatility on mean growth.

An endogenous Taylor condition in an endogenous growth monetary policy model

OpenAIRE

Le, Mai Vo; Gillman, Max; Minford, Patrick

2007-01-01

The paper derives a Taylor condition as part of the agent's equilibrium behavior in an endogenous growth monetary economy. It shows the assumptions necessary to make it almost identical to the original Taylor rule, and that it can interchangably take a money supply growth rate form. From the money supply form, simple policy experiments are conducted. A full central bank policy model is derived that includes the Taylor condition along with equations comparable to the standard aggregate-demand/...

Critique of the neoclassical theory of growth and distribution

Directory of Open Access Journals (Sweden)

Luigi L. Pasinetti

2000-12-01

Full Text Available The paper surveys the main theories of income distribution in their relationship with the theories of economic growth. First, the Classical approach is considered, focusing on the Ricardian theory. Then the neoclassical theory is discussed, highlighting its origins (Bohm-Bawerk, Wicksell, Clark and the role of the aggregate production function. The emergence of a "Keynesian" theory of income distributionin the wake of Harrod's model of growth is then recalled together with the surprising resurgence of the neoclassical theory (following the contributions of Solow and Meade. But, as the paper shows, the neoclassical theory of income distributionlacks logical consistency and has shaky foundations, as has been revealed by the severecritiques moved to the neoclassical production function. Mainstream economic literature circumvents this problem by simply ignoring it, while the models of endogenous growth exclude the issue of distribution theory from their consideration. However, while mainstream economics bypasses the problems of incomedistribution, this is too relevant an issue to be ignored and a number of new research lines, briefly surveyed, try new approaches to it.

A General Outlook to the Endogenous Money Theory

OpenAIRE

ÖZGÜR, Gökçer

2008-01-01

The purpose of this study is to shed light on theorigins of the endogenous money theory and analyze the currentdebates on this topic. Endogenous money approach depends on a fundamental postulate: As banks meet the credit needs ofnon-financial businesses, new deposits emerge in the banking sector. Similarly,as the necessary reserves found for these new deposits the broad money expandsas well. Even though the central bank can intervene into this process it cannotfully control it. There...

Understanding the Drivers of Economic Growth: Grounding Endogenous Economic Growth Models in Resource-Advantage Theory

OpenAIRE

Hunt, Shelby D.

2012-01-01

Foss (2012) provides an informed and informative comment on my article “Trust, Personal Moral Codes, and the Resource-Advantage Theory of Competition: Explaining Productivity, Economic Growth, and Wealth Creation” (Hunt, 2012). In general, his comment is highly supportive of both the theory and the arguments developed in my article. He does, however, raise certain issues that need to be addressed. These issues relate to the concept of total factor productivity, the role of institutions in pro...

The role of material/energy resources and dematerialisation in economic growth theories

Energy Technology Data Exchange (ETDEWEB)

Ayres, R.U. [Center for the Management of Environmental Resources INSEAD, Fountainebleau (France); Van den Bergh, J.C.J.M. [Department of Spatial Economics, Free University, Amsterdam (Netherlands)

2000-06-01

The nature of energy and material resources in an endogenous growth theory framework is clarified. This involves three modifications of the conventional theory. Firstly, multiple feedback mechanisms or 'growth engines' are identified. Secondly, a production function distinguishes between resource use, technical efficiency and value creation. Thirdly, the impact of the cost of production through demand on growth is accounted for. A formal model is analytically solved under a condition of a constant growth rate. Given model complexity, numerical experiments are performed as well, providing relevant insights to the academic and political debates on 'environmental Kuznets curves' and 'dematerialization'. 49 refs.

Self-similar measures in multi-sector endogenous growth models

International Nuclear Information System (INIS)

La Torre, Davide; Marsiglio, Simone; Mendivil, Franklin; Privileggi, Fabio

2015-01-01

We analyze two types of stochastic discrete time multi-sector endogenous growth models, namely a basic Uzawa–Lucas (1965, 1988) model and an extended three-sector version as in La Torre and Marsiglio (2010). As in the case of sustained growth the optimal dynamics of the state variables are not stationary, we focus on the dynamics of the capital ratio variables, and we show that, through appropriate log-transformations, they can be converted into affine iterated function systems converging to an invariant distribution supported on some (possibly fractal) compact set. This proves that also the steady state of endogenous growth models—i.e., the stochastic balanced growth path equilibrium—might have a fractal nature. We also provide some sufficient conditions under which the associated self-similar measures turn out to be either singular or absolutely continuous (for the three-sector model we only consider the singularity).

ENDOGENOUS OR EXOGENOUS INNOVATION DEVELOPMENT IN INDUSTRY ON REGIONAL LEVEL?

Directory of Open Access Journals (Sweden)

Arkadiusz Świadek

2014-04-01

Full Text Available At the moment endogenous growth theory has become increasingly popular in the world of science, particularly in developed countries. This article aims to show, for two regions case, the needs and sense of applying this theory in the polish regions. Due to the low level of economic development of many Polish regions, they are unable to growth in a comparable rate as regions in developed countries. This explains the economic divergence between polish regions and the highly developed regions of Europe and the World. Stimulating economic growth is insufficient in such cases, because of the weakness of its internal factors. Therefore it is important to strengthen an external impact to keep internal development. It means that the endogenous growth theory is no reason to exist, in conditions of poor polish regions. Without external inputs there can’t be convergences processes. Therefore, the economic development of the Polish regions should be based on the exogenous growth theory.

Fungal mycelia show lag time before re-growth on endogenous carbon.

Science.gov (United States)

Pollack, Judith K; Li, Zheng Jian; Marten, Mark R

2008-06-15

Nutrient starvation is a common occurrence for filamentous fungi. To better understand the effects of starvation, we used a parallel plate flow chamber to study individual fungal mycelia when subjected to a step change in glucose concentration. We report the presence of a finite "lag time" in starved mycelia during which they ceased to grow/extend while switching from growth on exogenous carbon to re-growth on endogenous carbon. This lag time precedes other morphological or physiological changes such as change in growth rate (50-70% reduction), vacuolation (up to 16%), and decreased hyphal diameter (almost 50% reduction). Data suggests that during lag time, vacuolar degradation produces sufficient endogenous carbon to support survival and restart hyphal extension. Lag time is inversely related to the size of the mycelium at the time of starvation, which suggests a critical flow of endogenous carbon to the apical tip. We present a mathematical model consistent with our experimental observations that relate lag time, area, and flow of endogenous carbon. (c) 2008 Wiley Periodicals, Inc.

Evolutionary Systems Theory, Universities, and Endogenous Regional Economic Development

Science.gov (United States)

Bowen, William M.

2007-01-01

Universities today are increasingly being viewed in terms of serving the purpose of economic development. This paper postulates that their chief purpose is to advance knowledge and that in doing so they effectuate regional economic growth and development through processes specified in the endogenous economic growth model. To achieve this purpose…

Inflation gifts and endogenous growth through learning-by-doing

OpenAIRE

Andrea Vaona

2013-01-01

We investigate the link between inflation, growth and unemployment nesting a model of fair wages into one of endogenous growth of learning by doing and assuming that firms protect wages' purchasing power against inflation in exchange of worker's effort. Unemployment decreases with higher inflation and real growth rates. These effects tends to vanish as inflation and growth increase. Depending on the assumptions on learning-by-doing mechanisms, the effect of inflation on growth can be either n...

Money demand in general equilibrium endogenous growth: Estimating the role of a variable interest elasticity

OpenAIRE

Gillman, Max; Otto, Glen

2006-01-01

The paper presents and tests a theory of the demand for money that is derived from a general equilibrium, endogenous growth economy, which in effect combines a special case of the shopping time exchange economy with the cash-in-advance framework. The model predicts that both higher inflation and financial innovation - that reduces the cost of credit - induce agents to substitute away from money towards exchange credit. The implied interest elasticity of money demand rises with the inflation r...

THE PROCESSES OF ENDOGENIZING IN THE ENDOGENOUS GROWTH: THE CASE OF TURKEY

Directory of Open Access Journals (Sweden)

OSMAN DEMİR

2013-06-01

Full Text Available The aim of this study is to state how the main inputs of endogenous growth, i.e. knowledge, human capital and technological progress are made endogenous by education, R&D, university-industry cooperation, learning by doing and diffusion within the production process. Competitiveness of firms and countries would increase as educated people enter into workforce; as R&D produces new technologies which are used in the production process; as theoretical knowledge meets with practice by university-industry cooperation; and as workers have more experience by learning by doing. In empirical analysis for Turkey is made by using data of 1970-2001 term it was found that a positive relationship among labour and capital factors and GNP and a negative relationship among education expenditures and foreign trade volume and capital stock.

Growth with Endogenous Capital, Knowledge, and Renewable Resources

Directory of Open Access Journals (Sweden)

Wei-Bin Zhang

2017-03-01

Full Text Available This paper proposes a dynamic economic model with endogenous technological change, physical capital and renewable resources. The model is a synthesis of the neoclassical growth theory, Arrow’s learning by doing, and some traditional dynamic models of renewable resources with an alternative approach to household behavior. The model describes a dynamic interdependence between technological change, physical accumulation, resource change, and division of labor under perfect competition. Because of its refined economic structure, the model analyzes some interactions between economic variables which are not found in the existing literature of economic growth. We simulate the model to demonstrate existence of equilibrium points and motion of the dynamic system. Our comparative dynamic analysis shows, for instance, that a rise in the capacity of the renewable resource increases the stock and reduces the price of the resource of the resource over time; the output levels of the two sectors, the total capital stock, and capital inputs of the two sectors are all increased; the labor distribution between the two sectors is slightly affected initially but is not affected in the long term; the rate of interest rises initially rise and is almost not affected in the long term; the per capita consumption levels of the good and the resource and the wage rate are increased.

Environmental policy, pollution, unemployment and endogenous growth

DEFF Research Database (Denmark)

Pedersen, Lars Haagen; Nielsen, Søren Bo; Sørensen, Peter Birch

1995-01-01

The paper develops a model of endogenous economic growth with pollution externalities and a labor market distorted by union monopoly power and by taxes and transfers. We study the optimal second-best pollution tax and abatement policy and find that a shift toward greener preferences will tend...... to reduce unemployment, although it will hamper growth. We also find that greater labor-market distortions call for higher pollution tax rates. Finally, we show that a switch from quantity control of pollution combined with grandfathering of pollution rights to regulation via emission charges has...

MODELS OF AN-TYPE INNOVATIVE ENDOGENOUS GROWTH AND THEIR SUBSTANTIATION

Directory of Open Access Journals (Sweden)

Askar A. Akaev

2015-01-01

Full Text Available The article presents an analysis of some classical models of economic growth of exogenous and endogenous type, based on the calculation of the motion of physical capital. It is shown that the simplest AN-type model, based on the calculation of population dynamics and endogenous technological progress, is more adequate for the description of the current economic development and provides a more accurate long-term forecast of economic dynamics.

Natural Disasters in a Two-Sector Model of Endogenous Growth

OpenAIRE

Masako Ikefuji; Ryo Horii

2006-01-01

Using an endogenous growth model with physical and human capital accumulation, this paper considers the sustainability of economic growth when the use of a polluting input (e.g., fossil fuels) intensifies the risk of capital destruction through natural disasters. We find that growth is sustainable only if the tax rate on the polluting input increases over time. The long-term rate of economic growth follows an inverted V-shaped curve relative to the growth rate of the environmental tax, and it...

La teoria neoclassica della crescita e della distribuzione (Neoclassical Theory of growth and Income Distribution

Directory of Open Access Journals (Sweden)

Robert M. Solow

2000-05-01

Full Text Available The paper surveys the neoclassical theory of growth. As a preliminary, the meaning of the adjective "neoclassical" is discussed. The basic model is then sketched, and the conditions ensuring a stationary state are illustrated. The issue of the convergence to a stationary state (and that of the speed of convergence is further considered. A discussion of "primary factors" opens the way to the "new" theory of growth, with endogenous technical progress. A number of extensions of the basic model are then recalled: two-sector and multi-sectoral models, overlapping generations models, the role of money in growth models.

Tax Evasion and Economic Growth in an Endogenous Growth Model

OpenAIRE

加藤, 秀弥; KATO, Hideya

2004-01-01

This paper presents an endogenous growth model with tax evasion where government expenditures affect production. An individual evades a tax so as to maximize his or her utility, the tax authority controls the detection probability to maximize net tax revenue, and the government chooses the income tax rate to maximize individuals’ utility. The main conclusions are as follows. First, the optical income tax rate with tax evasion is higher than that without tax evasion. Second, the rise in a ...

A recombinant endogenous retrovirus amplified in a mouse neuroblastoma is involved in tumor growth in vivo.

Science.gov (United States)

Pothlichet, Julien; Heidmann, Thierry; Mangeney, Marianne

2006-08-15

The theory of immunoediting postulates that tumor cells exhibit a reduced immunogenicity to escape eradication by the host immune system. It has been proposed that endogenous retroviruses--provided that they are active--could play a role in this process, via the immunosuppressive domain carried by their envelope protein. Here, we demonstrate that the Neuro-2a tumor cell line--originating from a spontaneous A/J mouse neuroblastoma--produces an infectious retrovirus that most probably results from a recombination event between 2 mouse endogenous retroviral elements. This Neuro-2a-associated recombinant retrovirus derives from the unique ecotropic provirus located at the Emv-1 locus, but with a gag sequence conferring B-tropism, thus allowing its high-level amplification in Neuro-2a cells. We show that knocking down -by RNA interference- this endogenous retrovirus in Neuro-2a cells has no effect on the transformed phenotype of the cells, but results in delayed tumor growth and prolonged animal survival, following engraftment of the cells into immunocompetent mice. Recombination between endogenous retroviruses, amplification of the resulting element and high-level expression of its immunosuppressive activity are therefore likely steps of an immunoediting process, leading to an invading tumor. Copyright 2006 Wiley-Liss, Inc.

Immunoneutralization of endogenous glucagon-like peptide-2 reduces adaptive intestinal growth in diabetic rats

DEFF Research Database (Denmark)

Hartmann, Bolette; Thulesen, Jesper; Hare, Kristine Juul

2002-01-01

in the proximal part of the small intestine (10.84+/-0.44 mm(2)). Antibody treatment had no effect on body weight, blood glucose concentrations and food intake. Thus, blocking of endogenous GLP-2 in a model of adaptive intestinal growth reduces the growth response, providing strong evidence for a physiological......Supraphysiological doses of glucagon-like peptide-2 (GLP-2) have been shown to induce intestinal growth by increasing villus height and crypt depth and by decreasing apoptosis, but a physiological effect of GLP-2 has not yet been demonstrated. Earlier, we found elevated levels of endogenous GLP-2...... in untreated streptozotocin diabetic rats associated with marked intestinal growth. In the present study, we investigated the role of endogenous GLP-2 for this adaptive response. We included four groups of six rats: (1) diabetic rats treated with saline, (2) diabetic rats treated with non-specific antibodies...

Theory of endogenous growth: political economy and mathematical economy Teoría del crecimiento endógeno. Economía política y economía matemática

Directory of Open Access Journals (Sweden)

Benavides G. Oscar A.

1997-06-01

Full Text Available Two essential features allow us to understand recent developments in growth theory: a new conceptualization to explain its nature, that is, the return to classical political economy and the introduction of the theory of public goods, and some mathematics that allow the formalization of this new conceptualization. With the development of bothn elements, the article presents the "new" theoretical framework, the formal conditions and the mathematical techniques needed to
understand current growth theory. This review of these new developments can serve as a point of reference to broeciet, or to question the formulations of endogenous growth theories.Dos aspectos esenciales que permiten entender los desarrollos recientes en la teoría del creciemiento: una nueva conceptualización para explicar sus naturaleza, es decir, el retorno a la economía política clásica y la introducción de una teoría de bienes públicos, y unas matemáticas que permiten formalizar esta nueva conceptualización. Con el desarrollo de ambos elementos, el artículo presenta el "nuevo" marco teórico, las condiciones formalesy las técnicas matemáticas necesarias para entender la actual teoría del creciento. Esta revisión de los nuevos desarrollos puede servir de punto de referencia para ampliar o cuestionar los planteamientos de las teorías de crecimiento endógeno.

Endogenous economic growth, EROI, and transition towards renewable energy

OpenAIRE

Victor Court; Pierre-André Jouvet; Frédéric Lantz

2015-01-01

Due to their initial lack of emphasis on energy and natural resources, exogenous and endogenous growth models have suffered the same critic regarding the limits to economic growth imposed by finite Earth resources. Thus, various optimal control models that incorporate energy or natural resources have been developed during the last decades. However, in all these models the importance of the Energy Return On Energy Investment (EROI) has never been raised. The EROI is the ratio of the quantity o...

The theory of endogenous money and the LM schedule: prelude to a reconstruction of ISLM

Directory of Open Access Journals (Sweden)

THOMAS I. PALLEY

Full Text Available ABSTRACT Money is at the center of macroeconomics, which makes understanding the money supply central for macroeconomic theory. This paper presents the Post Keynesian theory of endogenous money supply and shows how it is fundamentally different from the conventional money supply theory. The conventional approach relies on the money multiplier and bank lending is invisible. Post Keynesian theory discards the money multiplier and focuses on bank lending which drives money creation. The paper emphasizes the structuralist version of Post Keynesian theory which retains Keynes’ liquidity preference theory of long term interest rates and also recognizes banks are subject to financial constraints that limit their lending activities. The paper then shows how to derive the LM schedule in an endogenous money economy, which is a necessary prelude to reconstructing the ISLM model.

Social Security, Intergenerational Transfers, and Endogenous Growth

OpenAIRE

Junsen Zhang; Junxi Zhang

1998-01-01

In this paper, the effects of social security in a simple model of endogenous growth with alternative motives of having children are analyzed. It shows how the effects of social security depend on the size of the social security tax, the motive to have children, and the pattern of intergenerational transfers. The pattern of intergenerational transfers itself, however, is shown to change with the social security tax rate. When the social security tax is not too high, social security increases ...

La teoria neoclassica della crescita e della distribuzione (Neoclassical Theory of growth and Income Distribution

Directory of Open Access Journals (Sweden)

Robert M. Solow

2012-10-01

Full Text Available The paper surveys the neoclassical theory of growth. As a preliminary, the meaning of the adjective "neoclassical" is discussed. The basic model is then sketched, and the conditions ensuring a stationary state are illustrated. The issue of the convergence to a stationary state (and that of the speed of convergence is further considered. A discussion of "primary factors" opens the way to the "new" theory of growth, with endogenous technical progress. A number of extensions of the basic model are then recalled: two-sector and multi-sectoral models, overlapping generations models, the role of money in growth models.       JEL Codes: O41, E25Keywords: Distribution, Growth, Income Distribution, Income

Corporate Social Responsibility and Environmentally Sound Technology in Endogenous Firm Growth

Directory of Open Access Journals (Sweden)

Angela C. Chao

2017-02-01

Full Text Available We have entered the “New Normal” economy, with more emphasis on economic growth driven by innovation than resource. This paper investigates the impacts of firms considering corporate social responsibility and environmentally sound technology by building a three-stage Cournot competition model with asymmetric cost. The sustainable development of economic and endogenous firm growth achieves the win–win result in the theoretical model. Using data from 31 firms in China, this paper empirically researches on the relationships among corporate social responsibility, environmentally sound technology and firm endogenous growth. The results show that: (1 Marginal cost decreased with the increase of innovation, as well as getting government research and development subsidy, which has a positive effect on firm growth. (2 Consumers respond positively to corporate social responsibility initiative, the reputation of the firm can be improved. At the same time, environmentally sound technology objectively reduces the marginal cost of competitors because of the technology spillover. (3 Profit of a firm undertaking corporate social responsibility partly decreases, which has a negative effect on firm growth. The contradiction between corporate social responsibility and profit of firm could be adjusted, such as socially responsible investment fund hosed by institutional investors.

Ageing, human capital and demographic dividends with endogenous growth, labour supply and foreign capital

NARCIS (Netherlands)

Edle von Gaessler, Anne; Ziesemer, Thomas

2017-01-01

We modify a Lucas-type endogenous growth model to contain endogenous labour supply, imperfect international capital movements, and estimated interest and education time functions. Solutions based on realistic calibrations show that (i) the rate of human capital depreciation through ageing has a much

Fibroblast growth factor-mediated proliferation of central nervous system precursors depends on endogenous production of insulin-like growth factor I

International Nuclear Information System (INIS)

Drago, J.; Murphy, M.; Carroll, S.M.; Harvey, R.P.; Bartlett, P.F.

1991-01-01

Fibroblast growth factor stimulates proliferation and subsequent differentiation of precursor cells isolated from the neuroepithelium of embryonic day 10 mice in vitro. Here we show that fibroblast growth factor-induced proliferation is dependent on the presence of insulin-like growth factors (IGFs) and that IGF-I is endogenously produced by the neuroepithelial cells. Blocking of endogenous IGF-I activity with anti-IGF-I antibodies results in complete inhibition of fibroblast growth factor-mediated proliferation and in cell death. IGF-I alone acts as a survival agent. These observations correlate with the detection of transcripts for IGF-I and basic fibroblast growth factor in freshly isolated neuroepithelium and are consistent with an autocrine action of these factors in early brain development in vivo

Government technology push in agribusiness: a model of endogenous growth

Directory of Open Access Journals (Sweden)

Francisco Venegas Martínez

2008-10-01

Full Text Available This paper develops a model of endogenous growth where the government acts as a promoting agent to boost technology in agribusiness. In the framework of a monetary economy, the optimal level of government spending to enhance technology in the agricultural industry is characterized. Moreover the impact of such a spending on economic welfare is assessed. Finally, a number of agro-oriented policies to increase growth in the sector are established.

The endogenous preproglucagon system is not essential for gut growth homeostasis in mice

Directory of Open Access Journals (Sweden)

Pernille Wismann

2017-07-01

Conclusion: The present study indicates that the endogenous preproglucagon system, exemplified by the entire GCG gene and the receptors for GLP-1 and GLP-2, does not play a major role in normal gut development in the mouse. Furthermore, elevation in local intestinal and circulating levels of GLP-1 and GLP-2 achieved after VSG has limited impact on intestinal morphometry. Hence, although exogenous treatment with GLP-1 and GLP-2 analogs enhances gut growth, the contributions of endogenously-secreted GLP-1 and GLP-2 to gut growth may be more modest and highly context-dependent.

Money velocity in an endogenous growth business cycle with credit shocks

Czech Academy of Sciences Publication Activity Database

Benk, S.; Gillman, M.; Kejak, Michal

-, CDMC06/04 (2006), s. 1-39 Institutional research plan: CEZ:AV0Z70850503 Keywords : money velocity * business cycle * endogenous growth Subject RIV: AH - Economics http://www.st- and rews.ac.uk/economics/CDMA/papers/cp0604.pdf

Information and communication technologies in a multi-sector endogenous growth model

Czech Academy of Sciences Publication Activity Database

Vourvachaki, Evangelia

-, č. 386 (2009), s. 1-56 ISSN 1211-3298 Institutional research plan: CEZ:MSM0021620846 Keywords : multi-sector economy * endogenous growth * information and communication technologies Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/wp/Wp386.pdf

Endogenous Molecular-Cellular Network Cancer Theory: A Systems Biology Approach.

Science.gov (United States)

Wang, Gaowei; Yuan, Ruoshi; Zhu, Xiaomei; Ao, Ping

2018-01-01

In light of ever apparent limitation of the current dominant cancer mutation theory, a quantitative hypothesis for cancer genesis and progression, endogenous molecular-cellular network hypothesis has been proposed from the systems biology perspective, now for more than 10 years. It was intended to include both the genetic and epigenetic causes to understand cancer. Its development enters the stage of meaningful interaction with experimental and clinical data and the limitation of the traditional cancer mutation theory becomes more evident. Under this endogenous network hypothesis, we established a core working network of hepatocellular carcinoma (HCC) according to the hypothesis and quantified the working network by a nonlinear dynamical system. We showed that the two stable states of the working network reproduce the main known features of normal liver and HCC at both the modular and molecular levels. Using endogenous network hypothesis and validated working network, we explored genetic mutation pattern in cancer and potential strategies to cure or relieve HCC from a totally new perspective. Patterns of genetic mutations have been traditionally analyzed by posteriori statistical association approaches in light of traditional cancer mutation theory. One may wonder the possibility of a priori determination of any mutation regularity. Here, we found that based on the endogenous network theory the features of genetic mutations in cancers may be predicted without any prior knowledge of mutation propensities. Normal hepatocyte and cancerous hepatocyte stable states, specified by distinct patterns of expressions or activities of proteins in the network, provide means to directly identify a set of most probable genetic mutations and their effects in HCC. As the key proteins and main interactions in the network are conserved through cell types in an organism, similar mutational features may also be found in other cancers. This analysis yielded straightforward and testable

R&D and economic growth in Slovenia: A dynamic general equilibrium approach with endogenous growth

NARCIS (Netherlands)

Verbic, M.; Majcen, B.; Ivanova, O.; Cok, M.

2011-01-01

In the article, we model R&D as a major endogenous growth element in a small open economy general equilibrium framework and consider several R&D policy scenarios for Slovenia. Increase of the share of sectoral investment in R&D that is deductible from the corporate income tax and increase of

Semi adiabatic theory of seasonal Markov processes

Energy Technology Data Exchange (ETDEWEB)

Talkner, P [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1999-08-01

The dynamics of many natural and technical systems are essentially influenced by a periodic forcing. Analytic solutions of the equations of motion for periodically driven systems are generally not known. Simulations, numerical solutions or in some limiting cases approximate analytic solutions represent the known approaches to study the dynamics of such systems. Besides the regime of weak periodic forces where linear response theory works, the limit of a slow driving force can often be treated analytically using an adiabatic approximation. For this approximation to hold all intrinsic processes must be fast on the time-scale of a period of the external driving force. We developed a perturbation theory for periodically driven Markovian systems that covers the adiabatic regime but also works if the system has a single slow mode that may even be slower than the driving force. We call it the semi adiabatic approximation. Some results of this approximation for a system exhibiting stochastic resonance which usually takes place within the semi adiabatic regime are indicated. (author) 1 fig., 8 refs.

An endogenous growth model with embodied energy-saving technical change

International Nuclear Information System (INIS)

Van Zon, A.; Yetkiner, I. H.

2003-01-01

In this paper, we extend the Romer [Journal of Political Economy 98 (Part 2) (1990) S271] model in two ways. First we include energy consumption of intermediates. Second, intermediates become heterogeneous due to endogenous energy-saving technical change. We show that the resulting model can still generate steady state growth, but the growth rate depends negatively on the growth of real energy prices. The reason is that real energy price rises will lower the profitability of using new intermediate goods, and hence, the profitability of doing research, and therefore have a negative impact on growth. We also show that the introduction of an energy tax that is recycled in the form of an R and D subsidy may increase growth. We conclude that in order to have energy efficiency growth and output growth under rising real energy prices, a combination of R and D and energy policy is called for

Knowledge licensing in a model of R&D-driven endogenous growth

Czech Academy of Sciences Publication Activity Database

Jerbashian, Vahagn

2016-01-01

Roč. 16, č. 2 (2016), s. 555-579 ISSN 1935-1690 R&D Projects: GA ČR(CZ) GBP402/12/G097 Institutional support: PRVOUK-P23 Keywords : endogenous growth * in-house R&D * intellectual property regulation Subject RIV: AH - Economics Impact factor: 0.043, year: 2016

Productivity and Unemployment in a Two-country Model with Endogenous Growth

NARCIS (Netherlands)

van Schaik, A.B.T.M.; de Groot, H.L.F.

1997-01-01

Relative to the United States, most European countries have high rates of unemployment and low levels of productivity in manufacturing. To relate these issues, we develop a leader-follower model with endogenous growth and dual labour markets, stressing the role of high-tech and high-wage sectors in

Rapid warming accelerates tree growth decline in semi-arid forests of Inner Asia.

Science.gov (United States)

Liu, Hongyan; Park Williams, A; Allen, Craig D; Guo, Dali; Wu, Xiuchen; Anenkhonov, Oleg A; Liang, Eryuan; Sandanov, Denis V; Yin, Yi; Qi, Zhaohuan; Badmaeva, Natalya K

2013-08-01

Forests around the world are subject to risk of high rates of tree growth decline and increased tree mortality from combinations of climate warming and drought, notably in semi-arid settings. Here, we assess how climate warming has affected tree growth in one of the world's most extensive zones of semi-arid forests, in Inner Asia, a region where lack of data limits our understanding of how climate change may impact forests. We show that pervasive tree growth declines since 1994 in Inner Asia have been confined to semi-arid forests, where growing season water stress has been rising due to warming-induced increases in atmospheric moisture demand. A causal link between increasing drought and declining growth at semi-arid sites is corroborated by correlation analyses comparing annual climate data to records of tree-ring widths. These ring-width records tend to be substantially more sensitive to drought variability at semi-arid sites than at semi-humid sites. Fire occurrence and insect/pathogen attacks have increased in tandem with the most recent (2007-2009) documented episode of tree mortality. If warming in Inner Asia continues, further increases in forest stress and tree mortality could be expected, potentially driving the eventual regional loss of current semi-arid forests. © 2013 John Wiley & Sons Ltd.

Optimal Operational Monetary Policy Rules in an Endogenous Growth Model: a calibrated analysis

OpenAIRE

Arato, Hiroki

2009-01-01

This paper constructs an endogenous growth New Keynesian model and considers growth and welfare effect of Taylor-type (operational) monetary policy rules. The Ramsey equilibrium and optimal operational monetary policy rule is also computed. In the calibrated model, the Ramseyoptimal volatility of inflation rate is smaller than that in standard exogenous growth New Keynesian model with physical capital accumulation. Optimal operational monetary policy rule makes nominal interest rate respond s...

The theory of endogenous money and the LM schedule: prelude to a reconstruction of ISLM

OpenAIRE

PALLEY,THOMAS I.

2017-01-01

ABSTRACT Money is at the center of macroeconomics, which makes understanding the money supply central for macroeconomic theory. This paper presents the Post Keynesian theory of endogenous money supply and shows how it is fundamentally different from the conventional money supply theory. The conventional approach relies on the money multiplier and bank lending is invisible. Post Keynesian theory discards the money multiplier and focuses on bank lending which drives money creation. The paper em...

Influence of water table decline on growth allocation and endogenous gibberellins in black cottonwood

Energy Technology Data Exchange (ETDEWEB)

Rood, S.B.; Zanewich, K.; Stefura, C. [Lethbridge Univ., Lethbridge, AB (Canada). Dept. of Biological Sciences; Mahoney, J.M. [Alberta Environmental Protection, Lethbridge, AB (Canada)

2000-06-01

Cottonwoods have shown an adaptation to the riparian zone by coordinating root elongation to maintain contact with the water table, whose depth varies with the elevation of the adjacent river. The rate of water decline on growth allocation and concentrations of endogenous gibberellins (GAs) in black cottonwood saplings were studied at the University of Lethbridge, Alberta. Water declines were achieved by using rhizopods, and root elongation approximately doubled in response whereas leaf area was reduced. At some point, a greater water decline rate led to water stress resulting in reduced growth, increased leaf diffusive resistance, decreased water potential, and leaf senescence and abscission. After extraction of endogenous GAs, they were purified and analysed by gas chromatography-selected ion monitoring with internal ({sup 2}H{sub 2})GA standards. The results showed that GAs were higher in shoot tips and sequentially lower in basal stems, root tips, leaves and upper roots. Noticeable relationships did not appear between GA concentration and growth allocation across the water decline treatments. Only GA{sub 8} showed a consistent reduction in plants experiencing water table decline. This research did not permit the authors to conclude whether endogenous GAs play a primary role in the regulation of root elongation in response to water table decline. 7 figs., 25 refs.

Classical and semi-classical solutions of the Yang--Mills theory

International Nuclear Information System (INIS)

Jackiw, R.; Nohl, C.; Rebbi, C.

1977-12-01

This review summarizes what is known at present about classical solutions to Yang-Mills theory both in Euclidean and Minkowski space. The quantal meaning of these solutions is also discussed. Solutions in Euclidean space expose multiple vacua and tunnelling of the quantum theory. Those in Minkowski space-time provide a semi-classical spectrum for a conformal generator

Local economic development in theories of regional economies and rural studies

Directory of Open Access Journals (Sweden)

Kačar Bahrija

2016-01-01

Full Text Available In this paper is a detailed analysis of the basics in the theory of economic development during the period from mid last century until today. It states the most significant theories, points out their ranges, offers a critical review regarding their treatment of development, especially regional, rural and local one. It observes those theories according to different classifications existing in scientific literature, primarily the ascend theory, stagnation theory, balanced economic growth theory; then, short-term and long-term development and growth theories; traditional and endogenous theories; economic growth stages theory emphasized after the WWII; structural changes theory; dependency theory, neo-classic counter-revolution theory and endogenous theory as a new growth theory. The analysis becomes wider with a study on development in regional economy theories and rural studies and it systematizes the classification of those theories according to regional economy academics. Distancing ourselves from any particular division as the most suitable and acceptable one, the theories are treated separately and in an historic context, in order to encircle the time framework which from modern theories, dealing with local level development difficulties, resulted. It asserts The Community-led Rural Development Theory, often referred to as the Community Development Theory, or marked as Bottom-up Partnership Approach. The analysis of development theories asserts that mixed exogenous - endogenous approach to development links the rural/local development to the globalization process mostly due to fast technology changes of the IT and communication sectors.

Exogenous vs Endogenous Growth in the EU’s EaP and Central Asian Countries

Directory of Open Access Journals (Sweden)

Sharipov Ilkhom

2016-12-01

Full Text Available The main purpose of this paper is to determine and analyse the factors that affected economic growth in the EU’s Eastern Partnership and Central Asian countries in the 2000-2015 period. Economic growth is one of the main targets of economic policy of any country and influenced by various determinants. Of particular interest is the endogenous and exogenous nature of these factors. Having classified these factors into exogenous and endogenous ones, we examined and determined the significance and robustness of various factors influencing the economic growth in these countries, like investment, human capital, research and development, economic policies and macroeconomic conditions, openness to trade, geography, political factors and others. Correlation and factor analysis showed significance and strong association of GDP per capita with physical, human capital, and R&D in EaP countries and with natural resources and active population share in Central Asian countries.

Endogenous fertility and development traps with endogenous lifetime

OpenAIRE

Fanti, Luciano; Gori, Luca

2010-01-01

We extend the literature on endogenous lifetime and economic growth by Chakraborty (2004) and Bunzel and Qiao (2005) to endogenous fertility. We show that development traps due to underinvestments in health cannot appear when fertility is an economic decision variable and the costs of children are represented by a constant fraction of the parents' income used for their upbringing.

Critica della teoria neoclassica della crescita e della distribuzione (A Critique of the Neoclassical Theory of Growth and Income Distribution

Directory of Open Access Journals (Sweden)

Luigi Pasinetti

2012-10-01

Full Text Available The paper surveys the main theories of income distribution in their relationship with the theories of economic growth. First, the Classical approach is considered, focusing on the Ricardian theory. Then the neoclassical theory is discussed, highlighting its origins (Bohm-Bawerk, Wicksell, Clark and the role of the aggregate production function. The emergence of a "Keynesian" theory of income distribution in the wake of Harrod's model of growth is then recalled together with the surprising resurgence of the neoclassical theory (following the contributions of Solow and Meade. But, as the paper shows, the neoclassical theory of income distribution lacks logical consistency and has shaky foundations, as has been revealed by the severe critiques moved to the neoclassical production function. Mainstream economic literature circumvents this problem by simply ignoring it; while the models of endogenous growth exclude the issue of distribution theory from their consideration. However, while mainstream economics bypasses the problems of income distribution, this is too relevant an issue to be ignored and a number of new research lines, briefly surveyed, try new approaches to it.          JEL Codes: O41, E25Keywords: Distribution, Economic Growth, Growth, Income Distribution, Income

JOB DISCRIMINATION AGAINST WOMEN AND ENDOGENOUS POPULATION CHANGE IN A GENERALIZED SOLOW GROWTH MODEL

OpenAIRE

Wei-Bin ZHANG

2017-01-01

This study examines economic growth and population change with discrimination against women in the labor market within the analytical framework of Solow’s neoclassical growth model. The study models dynamic interactions between wealth accumulation, time distribution between work, children caring, and leisure, population change with endogenous birth and mortality rates with gender discrimination. The production technology and markets are built on Solow’s neoclassical growth model. The basic me...

Protein Prenylation Constitutes an Endogenous Brake on Axonal Growth

Directory of Open Access Journals (Sweden)

Hai Li

2016-07-01

Full Text Available Suboptimal axonal regeneration contributes to the consequences of nervous system trauma and neurodegenerative disease, but the intrinsic mechanisms that regulate axon growth remain unclear. We screened 50,400 small molecules for their ability to promote axon outgrowth on inhibitory substrata. The most potent hits were the statins, which stimulated growth of all mouse- and human-patient-derived neurons tested, both in vitro and in vivo, as did combined inhibition of the protein prenylation enzymes farnesyltransferase (PFT and geranylgeranyl transferase I (PGGT-1. Compensatory sprouting of motor axons may delay clinical onset of amyotrophic lateral sclerosis (ALS. Accordingly, elevated levels of PGGT1B, which would be predicted to reduce sprouting, were found in motor neurons of early- versus late-onset ALS patients postmortem. The mevalonate-prenylation pathway therefore constitutes an endogenous brake on axonal growth, and its inhibition provides a potential therapeutic approach to accelerate neuronal regeneration in humans.

The semi classical laser theory and some applications of laser

International Nuclear Information System (INIS)

Abdalla, Abbaker Ali

1995-04-01

The semi classical laser theory is concerned with the interaction between light and matter in such a way that the matter is treated quantum-mechanically whereas light is treated in terms of the classical electromagnetic equations. In this work the Maxwell-Bloch equations are employed to describe the interaction between light and matter. Applications of the theory as well as different types of lasers are reviewed. (Author)

The Endogenous-Exogenous Partition in Attribution Theory

Science.gov (United States)

Kruglanski, Arie W.

1975-01-01

Within lay explanation of actions, several significant inferences are assumed to follow from the partition between endogenous and exogenous attributions. An endogenous action is judged to constitute an end in itself; an exogenous action is judged to serve as a means to some further end. (Editor/RK)

Relationship between endogenous hydrogen sulfide and blood stasis syndrome based on the Qi-blood theory of Chinese medicine.

Science.gov (United States)

Li, Wei-wei; Guo, Hao; Wang, Xue-mei

2013-09-01

"Qi" and "blood" are two essential concepts in Chinese medicine (CM). As qi is intangible, the concept of qi is still controversial between CM and Western medicine. However, the endogenous hydrogen sulfide (H2S) and other gaseous signaling molecules provides a new approach for understanding the essence of qi in CM. Blood stasis syndrome is a common syndrome in CM. According to the CM theory, the incidence of blood stasis syndrome is closely correlated to the reckless movement of qi, as qi and blood are inseparable in regulating physiological functions. In recent years, more and more evidences suggest a close correlation between blood stasis syndrome and microcirculation dysfunction. In this paper, we discuss the relationship between endogenous H2S and blood stasis syndrome based on qi-blood theory of CM. We found that endogenous H2S maybe a material basis in concept of qi in CM, while dysfunctional microcirculation is the pathological basis of the blood stasis syndrome. As qi is closely associated with incidence and progression of blood stasis syndrome, endogenous H2S may play an important role in preventing and treating the blood stasis syndrome by improving the function of microcirculation.

A New-Growth Perspective on Non-Renewable Resources

DEFF Research Database (Denmark)

Groth, Christian

This article reviews issues related to the incorporation of non-renewable resources in the theory of economic growth and development. As an offshoot of the new growth theory of the last two decades a series of contributions have studied endogenous technical change in relation to resource scarcity...

Growth-based Theories for Declining Regions? A Note on Conceptualisations of Demographic Change for Regional Economic Development

Directory of Open Access Journals (Sweden)

Anke Matuschewski

2016-01-01

Full Text Available This article aims to critically assess the economic growth paradigm, which typically underlies most approaches to regional policymaking for demographic change. While population losses, ageing and outmigration – i.e. phenomena that are addressed as demographic change – have become a matter of urgency for many European regions, most regional economic development theories remain silent about the population decline affecting the economic growth and development prospects of regions. Consequently, regional policies usually rely on the concept of economic growth, yet neglect the complexity and importance of demographic change and how it relates to the economic sphere. Due to this lack in nuance, we argue that regional policymaking fails to design adequate policy support for regions facing persistent demographic change and economic stagnation or decline as a result. Based on these observations, the paper examines a selection of regional economic development theories in search for alternative concepts of growth and development in the context of demographic change. To this aim, globalisation peripheries are introduced as a fruitful conceptual point of reference and, in combination with endogenous regional development theories, discussed as an alternative approach for regional policymaking.

Diverging patterns with endogenous labor migration.

Science.gov (United States)

Reichlin, P; Rustichini, A

1998-05-05

"The standard neoclassical model cannot explain persistent migration flows and lack of cross-country convergence when capital and labor are mobile. Here we present a model where both phenomena may take place.... Our model is based on the Arrow-Romer approach to endogenous growth theory. We single out the importance of a (however weak) scale effect from the size of the workforce.... The main conclusion of this simple model is that lack of convergence, or even divergence, among countries is possible, even with perfect capital mobility and labor mobility." excerpt

The Evolution of Macroeconomic Theory and Implications for Teaching Intermediate Macroeconomics.

Science.gov (United States)

Froyen, Richard T.

1996-01-01

Traces the development of macroeconomic theory from John Maynard Keynes to modern endogenous growth theory. Maintains that a combination of interest in growth theory and related policy questions will play a prominent role in macroeconomics in the future. Recommends narrowing the gap between graduate school and undergraduate economics instruction.…

Differential model of macroeconomic growth with endogenic cyclicity

Directory of Open Access Journals (Sweden)

Mikhail I. Geraskin

2017-09-01

Full Text Available Objective to elaborate a mathematical model of economic growth taking into account the cyclical nature of macroeconomic dynamics with the model parameters based on the Russian economy statistics. Methods economic and mathematical modeling system analysis regression factor analysis econometric time series analysis. Results the article states that under unstable economic growth in Russia forecasting of strategic prospects of the Russian economy is one of the topical directions of scientific studies. Furthermore construction of predictive models should be based on multiple factors taking into account such basic concepts as the neoKeynesian HarrodDomar model Ramsey ndash Cass ndash Koopmans model S. V. Dubovskiyrsquos concept as well as the neoclassical growth model by R. Solow. They served as the basis for developing a multifactor differential economic growth model which is a modification of the neoclassical growth model by R. Solow taking into account the laborsaving and capitalsaving forms of scientifictechnical progress and the Keynesian concept of investment. The model parameters are determined based on the dynamics of actual GDP employment fixed assets and investments in fixed assets for 19652016 in Russia on the basis of official statistics. The generalized model showed the presence of longwave fluctuations that are not detected during the individual periods modeling. The cyclical nature of macroeconomic dynamics with a period of 54 years was found which corresponds to the parameters of long waves by N. D. Kondratiev. Basing on the model the macroeconomic growth forecast was generated which shows that after 2020 the increase of scientifictechnical progress will be negative. Scientific novelty a model is proposed of the scientifictechnical progress indicator showing the growth rate of the capital productivity ratio to the saving rate a differential model of macroeconomic growth is obtained which endogenously takes cyclicity into account

ECONOMIC GROWTH THEORIES, CONCEPTUAL ELEMENTS, CHARACTERISTICS

Directory of Open Access Journals (Sweden)

Florina, POPA

2014-11-01

Full Text Available The approach of economic growth involves understanding the concept and growth factors, respectively, analysing the growth theories, their trend in the context of the development of economic and social life. The economic growth signifies a process aimed at increasing activities in the national economy, expressed by macroeconomic indicators, respectively, the dynamics of the overall Gross Domestic Product or per inhabitant. It can appreciate that, in the short term, this process signifies phases of economic prosperity and on the long-term, expresses an upward trend, a consequence of the succession of increases and decreases. The study presents some elements which outlines the concept of economic growth, that is, definitions, meanings and the main characteristics of the theories of growth, as well as some of its determinant factors. Also, it gives a brief overview of the main theories of economic growth, as they have evolved over time, in line with the economic reality dynamics and the development of the instruments of economic analysis, starting from the classical theories to the new theories and models of economic growth of the modern age.

Asymptotic theory for Brownian semi-stationary processes with application to turbulence

DEFF Research Database (Denmark)

Corcuera, José Manuel; Hedevang, Emil; Pakkanen, Mikko S.

2013-01-01

This paper presents some asymptotic results for statistics of Brownian semi-stationary (BSS) processes. More precisely, we consider power variations of BSS processes, which are based on high frequency (possibly higher order) differences of the BSS model. We review the limit theory discussed......, which allow to obtain a valid central limit theorem for the critical region. Finally, we apply our statistical theory to turbulence data....

Small Firm Internationalization, Innovation, and Growth

NARCIS (Netherlands)

Boermans, M.A.; Roelfsema, H.J.

2016-01-01

This paper studies the effect of internationalization on innovation and firm performance (employment growth and sales growth) taking the interdependencies among the variables into account. Given the potential endogeneity, this study uses theory-driven instrumental variables and structural equation

Discovery of urinary biomarkers to discriminate between exogenous and semi-endogenous thiouracil in cattle: A parallel-like randomized design.

Science.gov (United States)

Van Meulebroek, Lieven; Wauters, Jella; Pomian, Beata; Vanden Bussche, Julie; Delahaut, Philippe; Fichant, Eric; Vanhaecke, Lynn

2018-01-01

In the European Union, the use of thyreostats for animal fattening purposes has been banned and monitoring plans have been established to detect potential abuse. However, this is not always straightforward as thyreostats such as thiouracil may also have a semi-endogenous origin. Therefore, this study aimed at defining urinary metabolites, which may aid in defining the origin of detected thiouracil. Hereto, a parallel-like randomized in vivo study was conducted in which calves (n = 8) and cows (n = 8) were subjected to either a control treatment, rapeseed-enriched diet to induce semi-endogenous formation, or thiouracil treatment. Urine samples (n = 330) were assessed through metabolic fingerprinting, employing liquid-chromatography and Q-ExactiveTM Orbitrap mass spectrometry. Urinary fingerprints comprised up to 40,000 features whereby multivariate discriminant analysis was able to point out significant metabolome differences between treatments (Q2(Y) ≥ 0.873). Using the validated models, a total of twelve metabolites (including thiouracil) were assigned marker potential. Combining these markers into age-dependent biomarker panels rendered a tool by which sample classification could be improved in comparison with thiouracil-based thresholds, and this during on-going thiouracil treatment (specificities ≥ 95.2% and sensitivities ≥ 85.7%), post-treatment (sensitivities ≥ 80% for ≥ 24 h after last administration), and simulated low-dose thiouracil treatment (exogenous thiouracil below 30 ng μL-1). Moreover, the metabolic relevance of revealed markers was supported by the suggested identities, for which a structural link with thiouracil could be determined in most cases. The proposed biomarker panels may contribute to a more justified decision-making in monitoring thiouracil abuse.

Does globalization contribute to economic growth in developing ...

African Journals Online (AJOL)

This paper examines empirically whether or not globalization contributes to economic growth in developing countries, drawing empirical lessons from Nigeria. The globalization – growth link, is anchored on Husain Schematic representation, Solow model, and the new growth (endogenous growth) theory. The paper adopts ...

Wound-induced endogenous jasmonates stunt plant growth by inhibiting mitosis.

Directory of Open Access Journals (Sweden)

Yi Zhang

Full Text Available When plants are repeatedly injured their growth is stunted and the size of organs such as leaves is greatly reduced. The basis of this effect is not well-understood however, even though it reduces yield of crops injured by herbivory, and produces dramatic effects exemplified in ornamental bonsai plants. We have investigated the genetic and physiological basis of this "bonsai effect" by repeatedly wounding leaves of the model plant Arabidopsis. This treatment stunted growth by 50% and increased the endogenous content of jasmonate (JA, a growth inhibitor, by seven-fold. Significantly, repeated wounding did not stunt the growth of the leaves of mutants unable to synthesise JA, or unable to respond to JA including coi1, jai3, myc2, but not jar1. The stunted growth did not result from reduced cell size, but resulted instead from reduced cell number, and was associated with reduced expression of CycB1;2. Wounding caused systemic disappearance of constitutively expressed JAZ1::GUS. Wounding also activates plant immunity. We show that a gene, 12-oxo-phytodienoate reductase, which catalyses a step in JA biosynthesis, and which we confirm is not required for defence, is however required for wound-induced stunting. Our data suggest that intermediates in the JA biosynthetic pathway activate defence, but a primary function of wound-induced JA is to stunt growth through the suppression of mitosis.

Wound-induced endogenous jasmonates stunt plant growth by inhibiting mitosis.

Science.gov (United States)

Zhang, Yi; Turner, John G

2008-01-01

When plants are repeatedly injured their growth is stunted and the size of organs such as leaves is greatly reduced. The basis of this effect is not well-understood however, even though it reduces yield of crops injured by herbivory, and produces dramatic effects exemplified in ornamental bonsai plants. We have investigated the genetic and physiological basis of this "bonsai effect" by repeatedly wounding leaves of the model plant Arabidopsis. This treatment stunted growth by 50% and increased the endogenous content of jasmonate (JA), a growth inhibitor, by seven-fold. Significantly, repeated wounding did not stunt the growth of the leaves of mutants unable to synthesise JA, or unable to respond to JA including coi1, jai3, myc2, but not jar1. The stunted growth did not result from reduced cell size, but resulted instead from reduced cell number, and was associated with reduced expression of CycB1;2. Wounding caused systemic disappearance of constitutively expressed JAZ1::GUS. Wounding also activates plant immunity. We show that a gene, 12-oxo-phytodienoate reductase, which catalyses a step in JA biosynthesis, and which we confirm is not required for defence, is however required for wound-induced stunting. Our data suggest that intermediates in the JA biosynthetic pathway activate defence, but a primary function of wound-induced JA is to stunt growth through the suppression of mitosis.

A Discrete Heterogeneous-Group Economic Growth Model with Endogenous Leisure Time

Directory of Open Access Journals (Sweden)

Wei-Bin Zhang

2009-01-01

Full Text Available This paper proposes a one-sector multigroup growth model with endogenous labor supply in discrete time. Proposing an alternative approach to behavior of households, we examine the dynamics of wealth and income distribution in a competitive economy with capital accumulation as the main engine of economic growth. We show how human capital levels, preferences, and labor force of heterogeneous households determine the national economic growth, wealth, and income distribution and time allocation of the groups. By simulation we demonstrate, for instance, that in the three-group economy when the rich group's human capital is improved, all the groups will economically benefit, and the leisure times of all the groups are reduced but when any other group's human capital is improved, the group will economically benefit, the other two groups economically lose, and the leisure times of all the groups are increased.

Boundary crossover in semi-infinite non-equilibrium growth processes

International Nuclear Information System (INIS)

Allegra, Nicolas; Fortin, Jean-Yves; Henkel, Malte

2014-01-01

The growth of stochastic interfaces in the vicinity of a boundary and the non-trivial crossover towards the behaviour deep in the bulk are analysed. The causal interactions of the interface with the boundary lead to a roughness larger near to the boundary than deep in the bulk. This is exemplified in the semi-infinite Edwards–Wilkinson model in one dimension, from both its exact solution and numerical simulations, as well as from simulations on the semi-infinite one-dimensional Kardar–Parisi–Zhang model. The non-stationary scaling of interface heights and widths is analysed and a universal scaling form for the local height profile is proposed. (paper)

Household consumer debt, endogenous money and growth: A supermultiplier-based analysis

Directory of Open Access Journals (Sweden)

Riccardo Pariboni

2016-09-01

Full Text Available The paper provides a simple theoretical framework to assess the macroeconomic implications of debt-fuelled consumption. In particular, the analysis is conducted through an extended super-multiplier model with endogenous credit money, which highlights the role of the autonomous components of demand, and in particular autonomous consumption, as the main drivers of economic growth. The author sketches a comparison with alternative heterodox formulations. He argues that, unlike the neo-Kaleckian models, in the model proposed here output growth adjusts to the path of debt-financed consumption. Having treated investment as fully induced, it follows that also the rate of capital accumulation adjusts to the rate of growth, which is itself determined by the evolution of autonomous demand. Finally, it is shown that the stability of the ratio of debt to debtors’ income is affected, among other things, by the growth differential between workers’ autonomous consumption (and debt and the other autonomous components of demand, i.e. public expenditure and capitalists’ autonomous consumption. JEL Classification: E11, E12, E44, G01

Growth of single crystals from solutions using semi-permeable membranes

Science.gov (United States)

Varkey, A. J.; Okeke, C. E.

1983-05-01

A technique suitable for growth of single crystals from solutions using semi-preamble membranes is described. Using this technique single crystals of copper sulphate, potassium bromide and ammonium dihydrogen phosphate have been successfully grown. Advantages of this technique over other methods are discussed.

Habits, aspirations and endogenous fertility

OpenAIRE

Luciano Fanti

2012-01-01

Motivated by the increasing literature on endogenous preferences as well as on endogenous fertility, this paper investigates the implications of the interaction of the endogenous determination of the number of children with habit and aspiration formation in an OLG model. In contrast with the previous literature, we show that greater aspirations may lead to higher savings, and more interestingly, always increase the neoclassical economic growth.

Endogenous Vascular Endothelial Growth Factor-A (VEGF-A) Maintains Endothelial Cell Homeostasis by Regulating VEGF Receptor-2 Transcription*

Science.gov (United States)

E, Guangqi; Cao, Ying; Bhattacharya, Santanu; Dutta, Shamit; Wang, Enfeng; Mukhopadhyay, Debabrata

2012-01-01

Vascular endothelial growth factor A (VEGF-A) is one of the most important factors controlling angiogenesis. Although the functions of exogenous VEGF-A have been widely studied, the roles of endogenous VEGF-A remain unclear. Here we focused on the mechanistic functions of endogenous VEGF-A in endothelial cells. We found that it is complexed with VEGF receptor 2 (VEGFR-2) and maintains a basal expression level for VEGFR-2 and its downstream signaling activation. Endogenous VEGF-A also controls expression of key endothelial specific genes including VEGFR-2, Tie-2, and vascular endothelial cadherin. Of importance, endogenous VEGF-A differs from exogenous VEGF-A by regulating VEGFR-2 transcription through mediation of FoxC2 binding to the FOX:ETS motif, and the complex formed by endogenous VEGF-A with VEGFR-2 is localized within the EEA1 (early endosome antigen 1) endosomal compartment. Taken together, our results emphasize the importance of endogenous VEGF-A in endothelial cells by regulating key vascular proteins and maintaining the endothelial homeostasis. PMID:22167188

Growth and characterization of semi-polar (11-22) GaN on patterned (113) Si substrates

International Nuclear Information System (INIS)

Bai, J; Yu, X; Gong, Y; Hou, Y N; Zhang, Y; Wang, T

2015-01-01

Patterned (113) Si substrates have been fabricated for the growth of (11-22) semi-polar GaN, which completely eliminates one of the great issues in the growth of semi-polar GaN on silicon substrates, ‘Ga melting-back’. Furthermore, unlike any other mask patterning approaches which normally lead to parallel grooves along a particular orientation, our approach is to form periodic square window patterns. As a result, crack-free semi-polar (11-22) GaN with a significant improvement in crystal quality has been achieved, in particular, basal stacking faults (BSFs) have been significantly reduced. The mechanism for the defect suppression has been investigated based on detailed transmission electron microscopy measurements. It has been found that the BSFs can be impeded effectively at an early growth stage due to the priority growth along the 〈0001〉 direction. The additional 〈1-100〉 lateral growth above the masks results in a further reduction in dislocation density. The significant reduction in BSFs has been confirmed by low temperature photoluminescence measurements. (paper)

What can we learn from the endogeneization of the technical progress in GEM - E3? The case of the Kyoto protocol

International Nuclear Information System (INIS)

Fougeyrollas, A.; Le Mouel, P.; Zagame, P.

2007-01-01

This project aims to study how the evaluation of the policies of fight against the greenhouse effect gases emission studied at an european scale, in the framework of the Kyoto agreements, is modified when the applied model, of general equilibrium takes into account the behavior of endogenous growth described by the new theories. More specially, the authors calibrated a production module with endogenous growth properties in the model GEM-E3. The new developed module show the costs reduction of policies of greenhouse effect gases emission limitation for France and Europe. (A.L.B.)

Semi-determinate growth habit adjusts the vegetative-to-reproductive balance and increases productivity and water-use efficiency in tomato (Solanum lycopersicum).

Science.gov (United States)

Vicente, Mateus Henrique; Zsögön, Agustin; de Sá, Ariadne Felicio Lopo; Ribeiro, Rafael V; Peres, Lázaro E P

2015-04-01

Tomato (Solanum lycopersicum) shows three growth habits: determinate, indeterminate and semi-determinate. These are controlled mainly by allelic variation in the self-pruning (SP) gene family, which also includes the "florigen" gene single flower TRUSS (SFT). Determinate cultivars have synchronized flower and fruit production, which allows mechanical harvesting in the tomato processing industry, whereas indeterminate ones have more vegetative growth with continuous flower and fruit formation, being thus preferred for fresh market tomato production. The semi-determinate growth habit is poorly understood, although there are indications that it combines advantages of determinate and indeterminate growth. Here, we used near-isogenic lines (NILs) in the cultivar Micro-Tom (MT) with different growth habit to characterize semi-determinate growth and to determine its impact on developmental and productivity traits. We show that semi-determinate genotypes are equivalent to determinate ones with extended vegetative growth, which in turn impacts shoot height, number of leaves and either stem diameter or internode length. Semi-determinate plants also tend to increase the highly relevant agronomic parameter Brix × ripe yield (BRY). Water-use efficiency (WUE), evaluated either directly as dry mass produced per amount of water transpired or indirectly through C isotope discrimination, was higher in semi-determinate genotypes. We also provide evidence that the increases in BRY in semi-determinate genotypes are a consequence of an improved balance between vegetative and reproductive growth, a mechanism analogous to the conversion of the overly vegetative tall cereal varieties into well-balanced semi-dwarf ones used in the Green Revolution. Copyright © 2015 Elsevier GmbH. All rights reserved.

2nd International Symposium on Semi-Markov Models : Theory and Applications

CERN Document Server

Limnios, Nikolaos

1999-01-01

This book presents a selection of papers presented to the Second Inter­ national Symposium on Semi-Markov Models: Theory and Applications held in Compiegne (France) in December 1998. This international meeting had the same aim as the first one held in Brussels in 1984 : to make, fourteen years later, the state of the art in the field of semi-Markov processes and their applications, bring together researchers in this field and also to stimulate fruitful discussions. The set of the subjects of the papers presented in Compiegne has a lot of similarities with the preceding Symposium; this shows that the main fields of semi-Markov processes are now well established particularly for basic applications in Reliability and Maintenance, Biomedicine, Queue­ ing, Control processes and production. A growing field is the one of insurance and finance but this is not really a surprising fact as the problem of pricing derivative products represents now a crucial problem in economics and finance. For example, stochastic mode...

Communication: Recovering the flat-plane condition in electronic structure theory at semi-local DFT cost

Science.gov (United States)

Bajaj, Akash; Janet, Jon Paul; Kulik, Heather J.

2017-11-01

The flat-plane condition is the union of two exact constraints in electronic structure theory: (i) energetic piecewise linearity with fractional electron removal or addition and (ii) invariant energetics with change in electron spin in a half filled orbital. Semi-local density functional theory (DFT) fails to recover the flat plane, exhibiting convex fractional charge errors (FCE) and concave fractional spin errors (FSE) that are related to delocalization and static correlation errors. We previously showed that DFT+U eliminates FCE but now demonstrate that, like other widely employed corrections (i.e., Hartree-Fock exchange), it worsens FSE. To find an alternative strategy, we examine the shape of semi-local DFT deviations from the exact flat plane and we find this shape to be remarkably consistent across ions and molecules. We introduce the judiciously modified DFT (jmDFT) approach, wherein corrections are constructed from few-parameter, low-order functional forms that fit the shape of semi-local DFT errors. We select one such physically intuitive form and incorporate it self-consistently to correct semi-local DFT. We demonstrate on model systems that jmDFT represents the first easy-to-implement, no-overhead approach to recovering the flat plane from semi-local DFT.

The endogenous preproglucagon system is not essential for gut growth homeostasis in mice.

Science.gov (United States)

Wismann, Pernille; Barkholt, Pernille; Secher, Thomas; Vrang, Niels; Hansen, Henrik B; Jeppesen, Palle Bekker; Baggio, Laurie L; Koehler, Jacqueline A; Drucker, Daniel J; Sandoval, Darleen A; Jelsing, Jacob

2017-07-01

The prevalence of obesity and related co-morbidities is reaching pandemic proportions. Today, the most effective obesity treatments are glucagon-like peptide 1 (GLP-1) analogs and bariatric surgery. Interestingly, both intervention paradigms have been associated with adaptive growth responses in the gut; however, intestinotrophic mechanisms associated with or secondary to medical or surgical obesity therapies are poorly understood. Therefore, the objective of this study was to assess the local basal endogenous and pharmacological intestinotrophic effects of glucagon-like peptides and bariatric surgery in mice. We used in situ hybridization to provide a detailed and comparative anatomical map of the local distribution of GLP-1 receptor ( Glp1r ), GLP-2 receptor ( Glp2r ), and preproglucagon ( Gcg ) mRNA expression throughout the mouse gastrointestinal tract. Gut development in GLP-1R-, GLP-2R-, or GCG-deficient mice was compared to their corresponding wild-type controls, and intestinotrophic effects of GLP-1 and GLP-2 analogs were assessed in wild-type mice. Lastly, gut volume was determined in a mouse model of vertical sleeve gastrectomy (VSG). Comparison of Glp1r , Glp2r , and Gcg mRNA expression indicated a widespread, but distinct, distribution of these three transcripts throughout all compartments of the mouse gastrointestinal tract. While mice null for Glp1r or Gcg showed normal intestinal morphology, Glp2r -/- mice exhibited a slight reduction in small intestinal mucosa volume. Pharmacological treatment with GLP-1 and GLP-2 analogs significantly increased gut volume. In contrast, VSG surgery had no effect on intestinal morphology. The present study indicates that the endogenous preproglucagon system, exemplified by the entire GCG gene and the receptors for GLP-1 and GLP-2, does not play a major role in normal gut development in the mouse. Furthermore, elevation in local intestinal and circulating levels of GLP-1 and GLP-2 achieved after VSG has limited impact

Higher Education, Causality and Growth: A Comparison of France and Germany before the Second World War

Science.gov (United States)

Jaoul, Magali

2004-01-01

Economists were long unaware of the influence of knowledge upon the growth process. With theories of human capital and theories of endogenous growth, knowledge gained a central position in the growth process. However, this has not been proved in many industrialized countries. The nature of the relations between education and growth is hence far…

Multiple growth regimes: Insights from unified growth theory

OpenAIRE

Galor, Oded

2007-01-01

Unified Growth Theory uncovers the forces that contributed to the existence of multiple growth regimes and the emergence of convergence clubs. It suggests that differential timing of take-offs from stagnation to growth segmented economies into three fundamental regimes: slow growing economies in a Malthusian regime, fast growing countries in a sustained growth regime, and economies in the transition between these regimes. In contrast to existing research that links regime switching thresholds...

Linear extended neutron diffusion theory for semi-in finites homogeneous means

International Nuclear Information System (INIS)

Vazquez R, R.; Vazquez R, A.; Espinosa P, G.

2009-10-01

Originally developed for heterogeneous means, the linear extended neutron diffusion theory is applied to the limit case of monoenergetic neutron diffusion in a semi-infinite homogeneous mean with a neutron source, located in the coordinate origin situated in the frontier of dispersive material. The monoenergetic neutron diffusion is studied taking into account the spatial deviations in the neutron flux to the interfacial current caused by the neutron source, as well as the influence of the spatial deviations in the absorption rate. The developed pattern is an unidimensional model for an energy group obtained of application of volumetric average diffusion equation in the moderator. The obtained results are compared against the classic diffusion theory and qualitatively against the neutron transport theory. (Author)

A theoretical model of semi-elliptic surface crack growth

Directory of Open Access Journals (Sweden)

Shi Kaikai

2014-06-01

Full Text Available A theoretical model of semi-elliptic surface crack growth based on the low cycle strain damage accumulation near the crack tip along the cracking direction and the Newman–Raju formula is developed. The crack is regarded as a sharp notch with a small curvature radius and the process zone is assumed to be the size of cyclic plastic zone. The modified Hutchinson, Rice and Rosengren (HRR formulations are used in the presented study. Assuming that the shape of surface crack front is controlled by two critical points: the deepest point and the surface point. The theoretical model is applied to semi-elliptic surface cracked Al 7075-T6 alloy plate under cyclic loading, and five different initial crack shapes are discussed in present study. Good agreement between experimental and theoretical results is obtained.

ELEMENTS OF THE NEOCLASSICAL GROWTH THEORY

Directory of Open Access Journals (Sweden)

Florina Popa

2014-12-01

Full Text Available One of the relevant components of the contemporary economic science is the economic growth theory, the economic background of the time leading to new guidelines of the research. The neoclassical growth theory - the core of modern analysis - explains how the capital accumulation and technological changes affect the economy, significant for the analysis of the economic growth process being the Solow’s neoclassical growth model. The paper brief describes the elements of the economic growth model developed by Solow, both for the situation when it allows the explanation of extensive growth and that wherein the growth is of intensive nature, as a result of the intervention of exogenous technical progress – a determinant of factors productivity growth. It is highlighted the importance of the exogenous neoclassical model, proposed by Solow, who showed the determinant role of the technical progress in the economic growth phenomenon.

Simulation and theory of island growth on stepped substrates

International Nuclear Information System (INIS)

Pownall, C.D.

1999-10-01

The nucleation, growth and coalescence of islands on stepped substrates is investigated by Monte Carlo simulations and analytical theories. Substrate steps provide a preferential site for the nucleation of islands, making many of the important processes one-dimensional in nature, and are of potentially major importance in the development of low-dimensional structures as a means of growing highly ordered chains of 'quantum dots' or continuous 'quantum wires'. A model is developed in which island nucleation is entirely restricted to the step edge, islands grow in compact morphologies by monomer capture, and eventually coalesce with one another until a single continuous cluster of islands covers the entire step. A series of analytical theories is developed to describe the dynamics of the whole evolution. The initial nucleation and aggregation regimes are modeled using the traditional approach of rate equations, rooted in mean field theory, but incorporating corrections to account for correlations in the nucleation and capture processes. This approach is found to break down close to the point at which the island density saturates and a new approach is developed based upon geometric and probabilistic arguments to describe the saturation behaviour, including the characteristic dynamic scaling which is found to persist through the coalescence regime as well. A further new theory, incorporating arguments based on the geometry of Capture Zones, is presented which reproduces the dynamics of the coalescence regime. The, latter part of the. thesis considers the spatial properties of the system, in particular the spacing of the islands along the step. An expression is derived which describes the distribution of gap sizes, and this is solved using a recently-developed relaxation method. An important result is the discovery that larger critical island sizes tend to yield more evenly spaced arrays of islands. The extent of this effect is analysed by solving for critical island

An Accounting Method for Economic Growth

OpenAIRE

Hongchun Zhao

2012-01-01

As Chari et al. (2007) indicate, many growth theories explaining frictions in real economies are equivalent to a competitive economy, with some exogenous taxes. Using this idea, I developed an accounting method for identifying fundamental causes of economic growth. A two-sector neoclassical growth model with taxes is used as a prototype economy, and its equilibrium conditions define wedges. These wedges endogenously determine the long run growth rate, which is exogenous and not correlated wit...

Circulating levels of pegvisomant and endogenous growth hormone during prolonged pegvisomant therapy in patients with acromegaly

DEFF Research Database (Denmark)

Madsen, Michael; Fisker, Sanne; Feldt-Rasmussen, Ulla

2014-01-01

OBJECTIVE: To investigate whether pegvisomant treatment in acromegaly induces gradual elevations in endogenous serum growth hormone (GH) levels and whether serum pegvisomant levels predict the therapeutic outcome. PATIENTS AND METHODS: Seventeen patients (6 women), mean age 46·3 years (range: 23...... correlated with baseline growth hormone levels, whereas no associations between serum pegvisomant and either dose, gender, age or body weight were found. CONCLUSIONS: (1) Serum GH levels increased initially, but remained stable during prolonged pegvisomant treatment in patients with acromegaly, (2) serum...

The Simplest Unified Growth Theory

DEFF Research Database (Denmark)

Strulik, Holger; Weisdorf, Jacob Louis

This paper provides a unified growth theory, i.e. a model that explains the very long-run economic and demographic development path of industrialized economies, stretching from the pre-industrial era to present-day and beyond. Making strict use of Malthus' (1798) so-called preventive check...... hypothesis - that fertility rates vary inversely with the price of food - the current study offers a new and straightforward explanation for the demographic transition and the break with the Malthusian era. The current framework lends support to existing unified growth theories and is well in tune...

Rational growth of semi-polar ZnO texture on a glass substrate for optoelectronic applications

Science.gov (United States)

Lu, B.; Ma, M. J.; Ye, Y. H.; Lu, J. G.; He, H. P.; Ye, Z. Z.

2013-02-01

Semi-polar ZnO films with surface texture were grown on glass substrates via pulsed-laser deposition (PLD) through Co-Ga co-doping. Oxygen pressure (PO2) was found to have significant effects on the structural and optical properties of the Zn(Co, Ga)O (ZCGO) films. A self-textured film with (1\\,0\\,\\bar {1}\\,1) preferred orientation (PO) was achieved by varying the growth conditions including a crucial narrow PO2 window and growth time. A possible mechanism underlying the PO evolution and the final texture of the films was proposed, which can be attributed to the collaboration of the doping effect and the PO2-dependent evolutionary selection process, in which certain grains can have increased vertical growth rate with respect to the substrate surface through interplane diffusion. Moreover, the growth of undoped pure ZnO films proceeded by using the (1\\,0\\,\\bar {1}\\,1) ZCGO film as a buffer layer. The ZnO layers retained a semi-polar characteristic with improved crystallinity and better optical quality. The epitaxy-like orientation of ZnO layers grown on (1\\,0\\,\\bar {1}\\,1) ZCGO films has applications in the development of semi-polar ZnO-based light-emitting diodes.

Fiscal Deficit, National Saving and Sustainability of Economic Growth in Emerging Economies: A Dynamic GMM Panel Data Approach

Directory of Open Access Journals (Sweden)

Buscemi Antonino

2012-01-01

Full Text Available The neoclassical growth models argued that the movement to steady states; technology, exogenous rate of savings, population growth and technical progress stimulate higher growth levels (Solow 1956. Contrary to the neoclassical argument, endogenous growth model argues that, in the theory of endogenous growth, government play a significant role in promoting accumulation of knowledge, research and development, public investment, human capital development, law and order can generate growth both in the short and long run. Moreover, they assumed technical progress as endogenous variable for growth (Barro 1995. This study analyze the effects of fiscal deficit on sustainability of economic growth and provided new empirical evidence on the effects of fiscal deficit on saving and sustainability of economic growth based on the assumption of endogenous growth model. We estimated using the reduced form of GMM method for dynamic panels covers 1990-2009 for three emerging countries that includes China, India and South Africa.

Public Expenditures and Economic Growth: Was Wagner Right? Evidence from Turkey

Directory of Open Access Journals (Sweden)

Gizem Uzuner

2017-06-01

Full Text Available Going by Adolph Wagner’s theory, increased in public expenditure would have a significant influence growth. However, the endogenous growth theories posit that public sector either has direct or indirect impacts on economic growth. It is on this premise, we seek to examine and validate Wagner’s theory on the impact of current, investment and transfer expenditures on economic growth over the periods 1975-2014 for Turkey, using Johansen co-integration test and Granger causality test. Findings confirm Wagner’s law through the existence of a long term relationship between the variables, while public expenditures display a significant positive impact on economic growth.

Endogenous ROS levels in C. elegans under exogenous stress support revision of oxidative stress theory of life-history tradeoffs.

Science.gov (United States)

Smith, Samson W; Latta, Leigh C; Denver, Dee R; Estes, Suzanne

2014-07-24

The oxidative stress theory of life-history tradeoffs states that oxidative stress caused by damaging free radicals directly underpins tradeoffs between reproduction and longevity by altering the allocation of energetic resources between these tasks. We test this theory by characterizing the effects of exogenous oxidative insult and its interaction with thermal stress and diet quality on a suite of life-history traits and correlations in Caenorhabditis elegans nematodes. We also quantify demographic aging rates and endogenous reactive oxygen species (ROS) levels in live animals. Our findings indicate a tradeoff between investment in reproduction and antioxidant defense (somatic maintenance) consistent with theoretical predictions, but correlations between standard life-history traits yield little evidence that oxidative stress generates strict tradeoffs. Increasing oxidative insult, however, shows a strong tendency to uncouple positive phenotypic correlations and, in particular, to reduce the correlation between reproduction and lifespan. We also found that mild oxidative insult results in lower levels of endogenous ROS accompanied by hormetic changes in lifespan, demographic aging, and reproduction that disappear in combined-stress treatments--consistent with the oxidative stress theory of aging. Our findings demonstrate that oxidative stress is a direct contributor to life-history trait variation and that traditional tradeoffs are not necessary to invoke oxidative stress as a mediator of relationships between life-history traits, supporting previous calls for revisions to theory.

Endogenous money: the evolutionary versus revolutionary views

OpenAIRE

Louis-Philippe Rochon; Sergio Rossi

2013-01-01

The purpose of this paper is to shed light on the endogenous nature of money. Contrary to the established post-Keynesian, or evolutionary, view, this paper argues that money has always been endogenous, irrespective of the historical period. Instead of the evolutionary theory of money and banking that can be traced back to Chick (1986), this paper puts forward a revolutionary definition of endogenous money consistent with many aspects of post-Keynesian economics as well as with the monetary ci...

Cytokines as endogenous pyrogens.

Science.gov (United States)

Dinarello, C A

1999-03-01

Cytokines are pleiotropic molecules mediating several pathologic processes. Long before the discovery of cytokines as immune system growth factors or as bone marrow stimulants, investigators learned a great deal about cytokines when they studied them as the endogenous mediators of fever. The terms "granulocytic" or "endogenous pyrogen" were used to describe substances with the biologic property of fever induction. Today, we recognize that pyrogenicity is a fundamental biologic property of several cytokines and hence the clinically recognizeable property of fever links host perturbations during disease with fundamental perturbations in cell biology. In this review, the discoveries made on endogenous pyrogens are revisited, with insights into the importance of the earlier work to the present-day understanding of cytokines in health and in disease.

Implicit theories about intelligence and growth (personal best) goals: Exploring reciprocal relationships.

Science.gov (United States)

Martin, Andrew J

2015-06-01

There has been increasing interest in growth approaches to students' academic development, including value-added models, modelling of academic trajectories, growth motivation orientations, growth mindsets, and growth goals. This study sought to investigate the relationships between implicit theories about intelligence (incremental and entity theories) and growth (personal best, PB) goals - with particular interest in the ordering of factors across time. The study focused on longitudinal data of 969 Australian high school students. The classic cross-lagged panel design (using structural equation modelling) was employed to shed light on the ordering of Time 1 growth goals, incremental theories, and entity theories relative to Time 2 (1 year later) growth goals, incremental theories, and entity theories. Findings showed that Time 1 growth goals predicted Time 2 incremental theories (positively) and entity theories (negatively); Time 1 entity and incremental theories negatively predicted Time 2 incremental and entity theories respectively; but, Time 1 incremental theories and entity theories did not predict growth goals at Time 2. This suggests that entity and incremental theories are negatively reciprocally related across time, but growth goals seem to be directionally salient over incremental and entity theories. Implications for promoting growth goals and growth mindsets are discussed. © 2014 The British Psychological Society.

Semi-continuous and multigroup models in extended kinetic theory

International Nuclear Information System (INIS)

Koller, W.

2000-01-01

The aim of this thesis is to study energy discretization of the Boltzmann equation in the framework of extended kinetic theory. In case that external fields can be neglected, the semi- continuous Boltzmann equation yields a sound basis for various generalizations. Semi-continuous kinetic equations describing a three component gas mixture interacting with monochromatic photons as well as a four component gas mixture undergoing chemical reactions are established and investigated. These equations reflect all major aspects (conservation laws, equilibria, H-theorem) of the full continuous kinetic description. For the treatment of the spatial dependence, an expansion of the distribution function in terms of Legendre polynomials is carried out. An implicit finite differencing scheme is combined with the operator splitting method. The obtained numerical schemes are applied to the space homogeneous study of binary chemical reactions and to spatially one-dimensional laser-induced acoustic waves. In the presence of external fields, the developed overlapping multigroup approach (with the spline-interpolation as its extension) is well suited for numerical studies. Furthermore, two formulations of consistent multigroup approaches to the non-linear Boltzmann equation are presented. (author)

Prolonged limitation of tree growth due to warmer spring in semi-arid mountain forests of Tianshan, northwest China

International Nuclear Information System (INIS)

Wu Xiuchen; Liu Hongyan; Wang Yufu; Deng Minghua

2013-01-01

Based on radial tree growth measurements in nine plots of area 625 m 2 (369 trees in total) and climate data, we explored the possibly changing effects of climate on regional tree growth in the temperate continental semi-arid mountain forests in the Tianshan Mountains in northwest China during 1933–2005. Tree growth in our study region is generally limited by the soil water content of pre- and early growing season (February–July). Remarkably, moving correlation functions identified a clear temporal change in the relationship between tree growth and mean April temperature. Tree growth showed a significant (p < 0.05) and negative relationship to mean April temperature since approximately the beginning of the 1970s, which indicated that the semi-arid mountain forests are suffering a prolonged growth limitation in recent years accompanying spring warming. This prolonged limitation of tree growth was attributed to the effects of soil water limitation in early spring (March–April) caused by the rapid spring warming. Warming-induced prolonged drought stress contributes, to a large part, to the marked reduction of regional basal area increment (BAI) in recent years and a much slower growth rate in young trees. Our results highlight that the increasing water limitation induced by spring warming on tree growth most likely aggravated the marked reduction in tree growth. This work provides a better understanding of the effects of spring warming on tree growth in temperate continental semi-arid forests. (letter)

The effect of in vitro mycorrhization on growth characteristics, changes in endogenous hormones and performance of microplants in potato (Solanum tuberosum L.

Directory of Open Access Journals (Sweden)

Khosro PARVIZI

2015-12-01

Full Text Available Potato (Solanum tuberosum L. plantlets were inoculated in vitro with an arbuscular mycorrhizal fungus (Glomus intraradices and their growth response, performance and endogenous hormonal status evaluated. A factorial experiment based on a completely randomized design consisting of two potato cultivars (Agria and Sante and four culture media was conducted with four replications. The culture media included non-inoculated Murashige and Skoog (MS medium (control, inoculated MS medium, inoculated half-strength MS medium and inoculated MS medium without vitamins and sugar. To do inoculation, germinated spores of fungus were transferred to the root zone of plantlets. Colonization percentage, total chlorophyll content, internodes and stolon length, shoot diameter, shoot and root fresh and dry weight, leaf area and the level of three endogenous hormones (total auxins, gibberellins and cytokinins were determined. In addition, mini-tuber production was assayed quantitatively and qualitatively. Results demonstrated that the effect of two factors on all characteristics including mini-tuber production was different significantly. Interaction between cultivar and inoculation systems was significantly associated with endogen auxins as well as all range of mini-tuber production. The inoculated MS medium showed the better results, but it did not have significant difference to half-strength MS in terms of plantlet performance and growing parameters. Responses of both cultivars to inoculation were very conspicuous in the production of endogen hormones. Higher endogen hormone levels were associated with elevated growth parameters, greater biomass production and better plantlet performance.

Unequal Education, Poverty and Low Growth--A Theoretical Framework for Rural Education of China

Science.gov (United States)

Wu, Fangwei; Zhang, Deyuan; Zhang, Jinghua

2008-01-01

This paper constructs an intertemporal substitution educational model based on endogenous growth theory and examines the rural education, farmer income and rural economic growth problems in China. It shows that the households originally with the same economic endowment but different education endowment take different growth routes, the income…

Performance of Jatropha curcas L. in Semi-arid Zone: Seed Germination, Seedling Growth and Early Field Growth

Directory of Open Access Journals (Sweden)

Sharif AHAMAD

2013-05-01

Full Text Available There is a lack of information on basic agronomic properties of Jatropha curcas L. (jatropha cultivation on the marginal lands in the semi-arids. Evaluation of agronomic performance of identified elite strains of J. curcas in marginal lands would be of paramount importance for addressing gap areas in their agronomic properties and subsequently for harnessing their optimum economic potentials. The present study undertook the task of analysing the growth performance of a high oil bearing elite strain of J. curcas–DARL-2 in degraded land in semi-arid zone of Deccan Plateau, India. While undertaking the assessment of growth performance of elite strain DARL-2, two other native (wild strains (namely AHN-1 and AHN-2 of J. curcas were also considered so that a comparative evaluation could be carried out. The role of gypsum was also investigated on J. curcas in the nursery stage as well its carry over effects on growth performance of transplanted trees in the field. Two types of substrates, gypsum-treated soil (GS and untreated soil (SL were used for growing seedlings of all the three jatropha strains. Seedlings (120-days-old of DARL-2 exhibited greater plant height, collar diameter and number of branches but root length was greater in the local strains. In the second year of field transplantation, DARL-2 strain exhibited significantly (p<0.05 greater plant height and number of branches/plant. No carry over effects of gypsum treatment were observed in field transplanted plants as none of the growth parameters significantly varied among the substrate types.

R&D and economic growth in Slovenia: A dynamic general equilibrium approach with endogenous growth

Directory of Open Access Journals (Sweden)

Verbič Miroslav

2011-01-01

Full Text Available In the article, we model R&D as a major endogenous growth element in a small open economy general equilibrium framework and consider several R&D policy scenarios for Slovenia. Increase of the share of sectoral investment in R&D that is deductible from the corporate income tax and increase of government spending on R&D turned out to be the most effective suggested policy measures. While the former policy measure is still followed in part by an undesired transfer of the tax relief to dividends, a moderate increase of government spending on R&D boosts long-run productivity in the economy, thus increasing the future value of firms, which is reflected in a desired dividend increase. The households that would gain more utility from such policy scenarios are those with more skilled and highly skilled labour, but not the very top earners in the economy.

Calculation of the spin-isospin response functions in an extended semi-classical theory

International Nuclear Information System (INIS)

Chanfray, G.

1987-01-01

We present a semi-classical calculation of the spin isospin response-functions beyond Thomas-Fermi theory. We show that surface-peaked ℎ 2 corrections reduce the collective effects predicted by Thomas-Fermi calculations. These effects, small for a volume response, become important for surface responses probed by hadrons. This yields a considerable improvement of the agreement with the (p, p') Los Alamos data

The Role of Material/Energy Resources and Dematerialisation in Economic Growth Theories

OpenAIRE

Ayres, Robert U.; van den Bergh, Jeroen C.J.M.

2000-01-01

The nature of energy and material resources in an endogenous growththeory framework isclarified. This involves three modifications of the conventionaltheory. Firstly, multiple feedbackmechanisms or “growth engines” are identified. Secondly, a productionfunction distinguishesbetween resource use, technical efficiency and value creation.Thirdly, the impact of the cost ofproduction through demand on growth is accounted for. A formal modelis analytically solvedunder a condition of a constant grow...

Hume and Endogenous Money

OpenAIRE

Maria Pia Paganelli

2006-01-01

David Hume’s monetary theory has three standard yet inconsistent readings. As a forefather of the quantity theory of money, Hume sees money as neutral. As an inflationist, Hume sees an active positive role for monetary policy. As a monetarist, Hume sees an active positive role for monetary policy only in the short run. This paper reads Hume consistently instead by showing that for Hume money is endogenous and demand-driven. Hume would read the money equation in terms of reverse causation and ...

Endogenous cueing attenuates object substitution masking.

Science.gov (United States)

Germeys, Filip; Pomianowska, I; De Graef, P; Zaenen, P; Verfaillie, K

2010-07-01

Object substitution masking (OSM) is a form of visual masking in which a briefly presented target surrounded by four small dots is masked by the continuing presence of the four dots after target offset. A major parameter in the prediction of OSM is the time required for attention to be directed to the target following its onset. Object substitution theory (Di Lollo et al. in J Exp Psychol Gen 129:481-507, 2000) predicts that the sooner attention can be focused at the target's location, the less masking will ensue. However, recently Luiga and Bachmann (Psychol Res 71:634-640, 2007) presented evidence that precueing of attention to the target location prior to target-plus-mask onset by means of a central (endogenous) arrow cue does not reduce OSM. When attention was cued exogenously, OSM was attenuated. Based on these results, Luiga and Bachmann argued that object substitution theory should be adapted by differentiating the ways of directing attention to the target location. The goal of the present study was to further examine the dissociation between the effects of endogenous and exogenous precueing on OSM. Contrary to Luiga and Bachmann, our results show that prior shifts of attention to the target location initiated by both exogenous and endogenous cues reduce OSM as predicted by object substitution theory and its computational model CMOS.

First Test of Stochastic Growth Theory for Langmuir Waves in Earth's Foreshock

Science.gov (United States)

Cairns, Iver H.; Robinson, P. A.

1997-01-01

This paper presents the first test of whether stochastic growth theory (SGT) can explain the detailed characteristics of Langmuir-like waves in Earth's foreshock. A period with unusually constant solar wind magnetic field is analyzed. The observed distributions P(logE) of wave fields E for two intervals with relatively constant spacecraft location (DIFF) are shown to agree well with the fundamental prediction of SGT, that P(logE) is Gaussian in log E. This stochastic growth can be accounted for semi-quantitatively in terms of standard foreshock beam parameters and a model developed for interplanetary type III bursts. Averaged over the entire period with large variations in DIFF, the P(logE) distribution is a power-law with index approximately -1; this is interpreted in terms of convolution of intrinsic, spatially varying P(logE) distributions with a probability function describing ISEE's residence time at a given DIFF. Wave data from this interval thus provide good observational evidence that SGT can sometimes explain the clumping, burstiness, persistence, and highly variable fields of the foreshock Langmuir-like waves.

A General Theory of Endogenous Market Structures

OpenAIRE

Federico Etro; Paolo Bertoletti

2014-01-01

We provide a unified approach to imperfect (monopolistic, Bertrand and Cournot) competition equilibria with demand functions derived from symmetric preferences over a large but finite number of goods. The equilibrium markups depend on the Morishima Elasticity of Substitution/Complementarity between goods, and can be derived directly from the utility functions and ranked unambiguously. We characterize the endogenous market structures, their dependence on market size, income and firms’ producti...

Diel time-courses of leaf growth in monocot and dicot species: endogenous rhythms and temperature effects.

Science.gov (United States)

Poiré, Richard; Wiese-Klinkenberg, Anika; Parent, Boris; Mielewczik, Michael; Schurr, Ulrich; Tardieu, François; Walter, Achim

2010-06-01

Diel (24 h) leaf growth patterns were differently affected by temperature variations and the circadian clock in several plant species. In the monocotyledon Zea mays, leaf elongation rate closely followed changes in temperature. In the dicotyledons Nicotiana tabacum, Ricinus communis, and Flaveria bidentis, the effect of temperature regimes was less obvious and leaf growth exhibited a clear circadian oscillation. These differences were related neither to primary metabolism nor to altered carbohydrate availability for growth. The effect of endogenous rhythms on leaf growth was analysed under continuous light in Arabidopsis thaliana, Ricinus communis, Zea mays, and Oryza sativa. No rhythmic growth was observed under continuous light in the two monocotyledons, while growth rhythmicity persisted in the two dicotyledons. Based on model simulations it is concluded that diel leaf growth patterns in mono- and dicotyledons result from the additive effects of both circadian-clock-controlled processes and responses to environmental changes such as temperature and evaporative demand. Apparently very distinct diel leaf growth behaviour of monocotyledons and dicotyledons can thus be explained by the different degrees to which diel temperature variations affect leaf growth in the two groups of species which, in turn, depends on the extent of the leaf growth control by internal clocks.

Semi-classical approximation and the problem of boundary conditions in the theory of relativistic particle radiation

International Nuclear Information System (INIS)

Akhiezer, A.I.; Shul'ga, N.F.

1991-01-01

The process of relativistic particle radiation in an external field has been studied in the semi-classical approximation rather extensively. The main problem arising in the studies is in expressing the formula of the quantum theory of radiation in terms of classical quantities, for example of the classical trajectories. However, it still remains unclear how the particle trajectory is assigned, that is which particular initial or boundary conditions determine the trajectory in semi-classical approximation quantum theory of radiation. We shall try to solve this problem. Its importance comes from the fact that in some cases one and the same boundary conditions may give rise to two or more trajectories. We demonstrate that this fact must necessarily be taken into account on deriving the classical limit for the formulae of the quantum theory of radiation, since it leads to a specific interference effect in radiation. The method we used to deal with the problem is similar to the method employed by Fock to analyze the problem of a canonical transformation in classical and quantum mechanics. (author)

JOB DISCRIMINATION AGAINST WOMEN AND ENDOGENOUS POPULATION CHANGE IN A GENERALIZED SOLOW GROWTH MODEL

Directory of Open Access Journals (Sweden)

Wei-Bin ZHANG

2017-06-01

Full Text Available This study examines economic growth and population change with discrimination against women in the labor market within the analytical framework of Solow’s neoclassical growth model. The study models dynamic interactions between wealth accumulation, time distribution between work, children caring, and leisure, population change with endogenous birth and mortality rates with gender discrimination. The production technology and markets are built on Solow’s neoclassical growth model. The basic mechanisms for population changes in the Barro-Becker fertility choice model and the Haavelmo population model are integrated to model the population change. This study also takes account of discrimination against woman in the labor market. We synthesize these dynamic forces in a compact framework by applying Zhang’s utility function. The model properties are studied by simulation. We find equilibrium points and illustrate motion of the dynamic system. We also examine the effects of changes in the discrimination against woman, the propensity to save, woman’s propensity to pursue leisure activities, the propensity to have children, woman’s human capital and man’s emotional involvement in children caring.

Endogenous Money, Non-neutrality and Interest-sensitivity in the Theory of Long Period Unemployment

OpenAIRE

Peter Docherty

2006-01-01

This paper investigates the role played by endogenous money in models with interest-sensitive expenditures. In particular, it examines the impact of endogenous money on a baseline neoclassical model arguing against the frequently asserted claim that traditional neoclassical macroeconomics is compatible with endogenous money. It demonstrates firstly that endogenous money is a sufficient condition to render unstable a neoclassical model characterised by interest-sensitive expenditures, full emp...

The Endogenous Feedback Network

DEFF Research Database (Denmark)

Augustenborg, Claudia Carrara

2010-01-01

proposals, it will first be considered the extents of their reciprocal compatibility, tentatively shaping an integrated, theoretical profile of consciousness. A new theory, the Endogenous Feedback Network (EFN) will consequently be introduced which, beside being able to accommodate the main tenets...... of the reviewed theories, appears able to compensate for the explanatory gaps they leave behind. The EFN proposes consciousness as the phenomenon emerging from a distinct network of neural paths broadcasting the neural changes associated to any mental process. It additionally argues for the need to include a 5th...

Effect of Low-Temperature Plasma on the Structure of Seeds, Growth and Metabolism of Endogenous Phytohormones in Pea (Pisum sativum L.)

Czech Academy of Sciences Publication Activity Database

Stolárik, T.; Henselová, M.; Martinka, M.; Novák, Ondřej; Záhoranová, A.; Černák, M.

2015-01-01

Roč. 35, č. 4 (2015), s. 659-676 ISSN 0272-4324 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Endogenous hormones * Germination * Growth parameters Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.811, year: 2015

Semi-Markov processes

CERN Document Server

Grabski

2014-01-01

Semi-Markov Processes: Applications in System Reliability and Maintenance is a modern view of discrete state space and continuous time semi-Markov processes and their applications in reliability and maintenance. The book explains how to construct semi-Markov models and discusses the different reliability parameters and characteristics that can be obtained from those models. The book is a useful resource for mathematicians, engineering practitioners, and PhD and MSc students who want to understand the basic concepts and results of semi-Markov process theory. Clearly defines the properties and

The effect of low ambient temperature on the febrile responses of rats to semi-purified human endogenous pyrogen.

Science.gov (United States)

Stitt, J T; Shimada, S G

1985-01-01

The febrile responses of Sprague-Dawley rats to semi-purified human endogenous pyrogen were studied at a thermoneutral ambient temperature (26 degrees C) and in the cold (3 degrees C). It was found that while rats developed typical monophasic febrile responses at thermoneutrality, febrile responses were absent in the cold-exposed rats. Experiments were conducted to determine whether this lack of febrile responses in cold-exposed rats was due to an inability of these animals to generate or retain heat in the cold. Thermogenesis and vasoconstriction were stimulated in cold-exposed rats by selectively cooling the hypothalamus, using chronically implanted thermodes. It was shown that, using this stimulus, metabolic rate could be increased by more than 50 percent and body temperature could be driven up at a rate of 5 degrees C/hour in rats exposed to the cold. Therefore, it was concluded that the lack of febrile responses of cold-exposed rats to pyrogen is in no way due to a physical or physiological inability to retain heat. Instead, it appears that in some manner cold exposure suppresses the sensitivity or responsiveness of the rat to pyrogenic stimuli.

Stochastic theory of grain growth

International Nuclear Information System (INIS)

Hu Haiyun; Xing Xiusan.

1990-11-01

The purpose of this note is to set up a stochastic theory of grain growth and to derive the statistical distribution function and the average value of the grain radius so as to match them with the experiment further. 8 refs, 1 fig

Endogeneity of Money Supply: Evidence From Turkey

Directory of Open Access Journals (Sweden)

Oguzhan Cepni

2017-02-01

Full Text Available There is a long discussion among academics and central bankers about the theories of money supply. According to the exogenous view, central banks have the full control over money supply via policy actions including the adjustments of interest rates and reserve ratios, both of which alter commercial banks’ lending decisions. However, the theory of endogenous money supply emphasizes the role of demand for bank loans in money creation. More specifically, banks create money by meeting the demand of economic agents. In this study, we investigate which of the money supply theories holds in Turkish economy for the period 2006-2015 by employing cointegration and causality tests. Our findings show that the causality runs from bank loans to money supply both in the short and long terms, which supports the endogenous view in a sense that central bank and the banks fully meet the total demand for money in Turkish economy.

Role of endogenous growth regulators in vernalization of seeds of radish (Raphanus sativus L.

Directory of Open Access Journals (Sweden)

Marian Michniewicz

2014-01-01

Full Text Available In embryos and cotyledons of seeds of the radish cv. `Tetra Iłówiecka' (which needs 20 days of vernalization and cv. 'Saxa' (which flowers without vernalization germinating at a vernalizing temperature of 5°C, the levels of auxins, gibberellins, cytokinins and the aibscisic acid-like inhibitor were determined, The analyses were performed after 5, 10, 15, 20, 25 and 30 days of chilling. The levels of growth regulators were also determined in embryos and cotyledons of seeds germinated at 260C when in the same growth stage as the material taken from chilled seeds. Cold treatment significantly affected the level of all endogenous growth regulators in embryos and cotyledons of both varieties. However, changes in the levels of these substances were not directly connected with the vernalization process. It was found that the vernalization of seeds of 'the radish cv. `Tetra Iłówiecka' increased the level of GAs in leaves, this did not, however, coincide with flower initiation. It is concluded that the role of GAs in flowering of the studied plants is connected rather with photoinduction than with vernalization.

Energetics of growth in semi-precocial shorebird chicks in a warm environment : The African black oystercatcher, Haematopus moquini

NARCIS (Netherlands)

Tjorve, Kathleen M. C.; Underhill, Les G.; Visser, G. Henk

2007-01-01

We studied prefledging growth, energy expenditure and time budgets of African Black Oystercatcher, Haematopus moquini, chicks on Robben Island, Western Cape, South Africa. The aim of the study was to investigate the effect of parental feeding on the growth and energetics of semi-precocial shorebird

Neutrophils responsive to endogenous IFN-beta regulate tumor angiogenesis and growth in a mouse tumor model.

Science.gov (United States)

Jablonska, Jadwiga; Leschner, Sara; Westphal, Kathrin; Lienenklaus, Stefan; Weiss, Siegfried

2010-04-01

Angiogenesis is a hallmark of malignant neoplasias, as the formation of new blood vessels is required for tumors to acquire oxygen and nutrients essential for their continued growth and metastasis. However, the signaling pathways leading to tumor vascularization are not fully understood. Here, using a transplantable mouse tumor model, we have demonstrated that endogenous IFN-beta inhibits tumor angiogenesis through repression of genes encoding proangiogenic and homing factors in tumor-infiltrating neutrophils. We determined that IFN-beta-deficient mice injected with B16F10 melanoma or MCA205 fibrosarcoma cells developed faster-growing tumors with better-developed blood vessels than did syngeneic control mice. These tumors displayed enhanced infiltration by CD11b+Gr1+ neutrophils expressing elevated levels of the genes encoding the proangiogenic factors VEGF and MMP9 and the homing receptor CXCR4. They also expressed higher levels of the transcription factors c-myc and STAT3, known regulators of VEGF, MMP9, and CXCR4. In vitro, treatment of these tumor-infiltrating neutrophils with low levels of IFN-beta restored expression of proangiogenic factors to control levels. Moreover, depletion of these neutrophils inhibited tumor growth in both control and IFN-beta-deficient mice. We therefore suggest that constitutively produced endogenous IFN-beta is an important mediator of innate tumor surveillance. Further, we believe our data help to explain the therapeutic effect of IFN treatment during the early stages of cancer development.

Semi-analytical quasi-normal mode theory for the local density of states in coupled photonic crystal cavity-waveguide structures

DEFF Research Database (Denmark)

de Lasson, Jakob Rosenkrantz; Kristensen, Philip Trøst; Mørk, Jesper

2015-01-01

We present and validate a semi-analytical quasi-normal mode (QNM) theory for the local density of states (LDOS) in coupled photonic crystal (PhC) cavity-waveguide structures. By means of an expansion of the Green's function on one or a few QNMs, a closed-form expression for the LDOS is obtained, ......-trivial spectrum with a peak and a dip is found, which is reproduced only when including both the two relevant QNMs in the theory. In both cases, we find relative errors below 1% in the bandwidth of interest.......We present and validate a semi-analytical quasi-normal mode (QNM) theory for the local density of states (LDOS) in coupled photonic crystal (PhC) cavity-waveguide structures. By means of an expansion of the Green's function on one or a few QNMs, a closed-form expression for the LDOS is obtained......, and for two types of two-dimensional PhCs, with one and two cavities side-coupled to an extended waveguide, the theory is validated against numerically exact computations. For the single cavity, a slightly asymmetric spectrum is found, which the QNM theory reproduces, and for two cavities a non...

Theory and Evidence on the Finance-Growth Relationship: The Virtuous and Unvirtuous Cycles

OpenAIRE

Lauretta, Eliana; Chaudhry, Sajid; Mullineux, Andy

2015-01-01

Since the 1980s, financial crises have tended to reoccur with increasing frequency and growing intensity. They are endogenously generated by the established OTD (Originate-To-Distribute) model within the new finance-growth paradigm. Good finance fosters the correct allocation of financial resources, the fair redistribution of wealth and positive economic growth (the virtuous cycle), whereas bad finance captures part of the created wealth and, thanks to a highly technologically advanced financ...

Local and global bifurcations in an economic growth model with endogenous labour supply and multiplicative external habits

Science.gov (United States)

Gori, Luca; Sodini, Mauro

2014-03-01

This paper analyses the mathematical properties of an economic growth model with overlapping generations, endogenous labour supply, and multiplicative external habits. The dynamics of the economy is characterised by a two-dimensional map describing the time evolution of capital and labour supply. We show that if the relative importance of external habits in the utility function is sufficiently high, multiple (determinate or indeterminate) fixed points and poverty traps can exist. In addition, periodic or quasiperiodic behaviour and/or coexistence of attractors may occur.

TOURISM, TRADE, EXTERNALITIES, AND PUBLIC GOODS IN A THREE-SECTOR GROWTH MODEL

Directory of Open Access Journals (Sweden)

Wei-Bin Zhang

2015-06-01

Full Text Available The purpose of this study is to introduce tourism, externalities, and public goods to a small-open growth with endogenous wealth and public goods supply. We develop the model on the basis of the Solow-Uzawa growth model, the neoclassical neoclassical growth theory with externalities, and ideas from tourism economics. The economy consists of three – service, industrial, and public - sectors. The production side is based on the traditional growth theories, while the household behavior is described by an alternative utility function proposed by Zhang. We introduce endogenous land distribution between housing and supply of services. The industrial and service sectors are perfectly competitive subject to the government’s taxation. The public sector is financially supported by the government. We introduce taxes not only on producers, but also on consumers’ incomes from wage, land, and interest of wealth, consumption of goods and services, and housing. We simulate the motion of the national economy and show the existence of a unique stable equilibrium. We carry out comparative dynamic analysis with regard to the rate of interest in the global market, the total productivity of the service sector, tax rate on the service sector, tax rate on consumption of services, human capital, the propensity to consume services, and the impact of public services on the productivity of the industrial sector. The comparative dynamic analysis provides some important insights into the complexity of open economies with endogenous wealth, public goods, and externalities.

Effects of leukemia inhibitory factor and basic fibroblast growth factor on free radicals and endogenous stem cell proliferation in a mouse model of cerebral infarction.

Science.gov (United States)

Huang, Weihui; Li, Yadan; Lin, Yufeng; Ye, Xue; Zang, Dawei

2012-07-05

The present study established a mouse model of cerebral infarction by middle cerebral artery occlusion, and monitored the effect of 25 μg/kg leukemia inhibitory factor and (or) basic fibroblast growth factor administration 2 hours after model establishment. Results showed that following administration, the number of endogenous neural stem cells in the infarct area significantly increased, malondialdehyde content in brain tissue homogenates significantly decreased, nitric oxide content, glutathione peroxidase and superoxide dismutase activity significantly elevated, and mouse motor function significantly improved as confirmed by the rotarod and bar grab tests. In particular, the effect of leukemia inhibitory factor in combination with basic fibroblast growth factor was the most significant. Results indicate that leukemia inhibitory factor and basic fibroblast growth factor can improve the microenvironment after cerebral infarction by altering free radical levels, improving the quantity of endogenous neural stem cells, and promoting neurological function of mice with cerebral infarction.

A theory of economic growth with material/energy resources and dematerialization: interaction of three growth mechanisms

NARCIS (Netherlands)

Ayes, R.U.; van den Bergh, J.C.J.M.

2005-01-01

The nature of energy and material resources in a non-optimizing growth theory framework is clarified. This involves two modifications of the conventional theory. Firstly, multiple feedback mechanisms or "growth engines" are identified, such that the impact of the cost of production through demand on

The chloroindole auxins of pea, strong plant growth hormones or endogenous herbicides

International Nuclear Information System (INIS)

Engvild, K.C.

1994-02-01

In this work the three theses below are discussed: 1) Identification and quantitative determination of the very strong plant hormone, the auxin 4-chloroindole-3-acetic acid methyl ester, in immature seeds of Pisum, Vicia, Lathyrus, and Lens spp. by incorporation of radioactive 36 Cl, thin layer chromatography, autoradiography, colour reactions, and gas chromatography/mass spectrometry. 2) The strong biological activity of 4-chloroindole-3-acetic acid and its analogues and its ability to induce strong, almost irreversible, ethylene evolution. 3) The possible role of chloroindole auxin in plants, particularly if it might be the hypothetical death hormone, secreted from developing seeds, which induces senescence and kills the mother plant at maturity; if plants generally have several auxin types, growth promoters and endogenous herbicides; and if other chlorine-containing plant hormones occur in developing seeds of other crop species. (au) (7 tabs., 8 ills., 144 refs.)

The endogenous preproglucagon system is not essential for gut growth homeostasis in mice

DEFF Research Database (Denmark)

Wismann, Pernille; Barkholt, Pernille; Secher, Thomas

2017-01-01

OBJECTIVE: The prevalence of obesity and related co-morbidities is reaching pandemic proportions. Today, the most effective obesity treatments are glucagon-like peptide 1 (GLP-1) analogs and bariatric surgery. Interestingly, both intervention paradigms have been associated with adaptive growth...... responses in the gut; however, intestinotrophic mechanisms associated with or secondary to medical or surgical obesity therapies are poorly understood. Therefore, the objective of this study was to assess the local basal endogenous and pharmacological intestinotrophic effects of glucagon-like peptides...... for GLP-1 and GLP-2, does not play a major role in normal gut development in the mouse. Furthermore, elevation in local intestinal and circulating levels of GLP-1 and GLP-2 achieved after VSG has limited impact on intestinal morphometry. Hence, although exogenous treatment with GLP-1 and GLP-2 analogs...

EXOGENOUS OR ENDOGENOUS MONEY SUPPLY: EVIDENCE FROM AUSTRALIA

OpenAIRE

ZATUL E. BADARUDIN; AHMED M. KHALID; MOHAMED ARIFF

2012-01-01

This paper investigates the nature of money supply in Australia over two separate monetary policy regimes: monetary and inflation targeting. The post-Keynesian theory on endogenous money was tested with the aim of investigating whether endogenous money supply, if it did exist, followed the accomodationist, structuralist or liquidity preference viewpoints. Data used are quarterly series from 1977 to 2007 and we used vector error-correction model for long-run and short-run causality tests. We f...

Growth factor involvement in tension-induced skeletal muscle growth

Science.gov (United States)

Vandenburgh, Herman H.

1993-01-01

Long-term manned space travel will require a better understanding of skeletal muscle atrophy which results from microgravity. Astronaut strength and dexterity must be maintained for normal mission operations and for emergency situations. Although exercise in space slows the rate of muscle loss, it does not prevent it. A biochemical understanding of how gravity/tension/exercise help to maintain muscle size by altering protein synthesis and/or degradation rate should ultimately allow pharmacological intervention to prevent muscle atrophy in microgravity. The overall objective is to examine some of the basic biochemical processes involved in tension-induced muscle growth. With an experimental in vitro system, the role of exogenous and endogenous muscle growth factors in mechanically stimulated muscle growth are examined. Differentiated avian skeletal myofibers can be 'exercised' in tissue culture using a newly developed dynamic mechanical cell stimulator device which simulates different muscle activity patterns. Patterns of mechanical activity which significantly affect muscle growth and metabolic characteristics were found. Both exogenous and endogenous growth factors are essential for tension-induced muscle growth. Exogenous growth factors found in serum, such as insulin, insulin-like growth factors, and steroids, are important regulators of muscle protein turnover rates and mechanically-induced muscle growth. Endogenous growth factors are synthesized and released into the culture medium when muscle cells are mechanically stimulated. At least one family of mechanically induced endogenous factors, the prostaglandins, help to regulate the rates of protein turnover in muscle cells. Endogenously synthesized IGF-1 is another. The interaction of muscle mechanical activity and these growth factors in the regulation of muscle protein turnover rates with our in vitro model system is studied.

Morphoelasticity: A theory of elastic growth

KAUST Repository

Goriely, Alain; Moulton, Derek

2011-01-01

This chapter is concerned with the modelling of growth processes in the framework of continuum mechanics and nonlinear elasticity. It begins by considering growth and deformation in a one-dimensional setting, illustrating the key relationship between growth, the elastic response of the material, and the generation of residual stresses. The general three-dimensional theory of morphoelasticity is then developed from conservation of mass and momentum balance equations. In the formulation, the multiplicative decomposition of the deformation tensor, the standard approach in morphoelasticity, is derived in a new way. A discussion of continuous growth is also included. The chapter concludes by working through a sample problem of a growing cylindrical tube. A stability analysis is formulated, and the effect of growth on mucosal folding, a commonly seen instability in biological tubes, is demonstrated.

Morphoelasticity: A theory of elastic growth

KAUST Repository

Goriely, Alain

2011-10-11

This chapter is concerned with the modelling of growth processes in the framework of continuum mechanics and nonlinear elasticity. It begins by considering growth and deformation in a one-dimensional setting, illustrating the key relationship between growth, the elastic response of the material, and the generation of residual stresses. The general three-dimensional theory of morphoelasticity is then developed from conservation of mass and momentum balance equations. In the formulation, the multiplicative decomposition of the deformation tensor, the standard approach in morphoelasticity, is derived in a new way. A discussion of continuous growth is also included. The chapter concludes by working through a sample problem of a growing cylindrical tube. A stability analysis is formulated, and the effect of growth on mucosal folding, a commonly seen instability in biological tubes, is demonstrated.

Applicability of special quasi-random structure models in thermodynamic calculations using semi-empirical Debye–Grüneisen theory

International Nuclear Information System (INIS)

Kim, Jiwoong

2015-01-01

In theoretical calculations, expressing the random distribution of atoms in a certain crystal structure is still challenging. The special quasi-random structure (SQS) model is effective for depicting such random distributions. The SQS model has not been applied to semi-empirical thermodynamic calculations; however, Debye–Grüneisen theory (DGT), a semi-empirical method, was used here for that purpose. The model reliability was obtained by comparing supercell models of various sizes. The results for chemical bonds, pair correlation, and elastic properties demonstrated the reliability of the SQS models. Thermodynamic calculations using density functional perturbation theory (DFPT) and DGT assessed the applicability of the SQS models. DGT and DFPT led to similar variations of the mixing and formation energies. This study provides guidelines for theoretical assessments to obtain the reliable SQS models and to calculate the thermodynamic properties of numerous materials with a random atomic distribution. - Highlights: • Various material properties are used to examine reliability of special quasi-random structures. • SQS models are applied to thermodynamic calculations by semi-empirical methods. • Basic calculation guidelines for materials with random atomic distribution are given.

A New Semi-Symmetric Unified Field Theory of the Classical Fields of Gravity and Electromagnetism

Directory of Open Access Journals (Sweden)

Suhendro I.

2007-10-01

Full Text Available We attempt to present a classical theoretical framework in which the gravitational and electromagnetic fields are unified as intrinsic geometric objects in the space-time manifold. For this purpose, we first present the preliminary geometric considerations dealing with the metric differential geometry of Cartan connections. The unified field theory is then developed as an extension of the general theory of relativity based on a semi- symmetric Cartan connection which is meant to be as close as possible structurally to the symmetric connection of the Einstein-Riemann space-time.

Impact of AlN seeding layer growth rate in MOVPE growth of semi-polar gallium nitride structures on high index silicon

Energy Technology Data Exchange (ETDEWEB)

Ravash, Roghaiyeh; Blaesing, Juergen; Hempel, Thomas; Noltemeyer, Martin; Dadgar, Armin; Christen, Juergen; Krost, Alois [Otto-von-Guericke-University Magdeburg, FNW/IEP/AHE, Postfach 4120, 39016 Magdeburg (Germany)

2011-03-15

We present metal organic vapor phase epitaxy growth of semi-polar GaN structures on high index silicon surfaces. The crystallographic structure of GaN grown on Si(112), (115), and (117) substrates is investigated by X-ray analysis and scanning electron microscopy. X-ray diffraction was performed in Bragg Brentano geometry as well as pole figure measurements. The results demonstrate that the orientation of GaN crystallites on Si is significantly dependent on thickness of the AlN seeding layer and TMAl-flow rate. We observe that the crystallographic structures of GaN by applying thin AlN seeding layers grown with high TMAl-flow rate depend on Si surface direction while they are independent for thicker layers. By applying such seeding layer we obtain single crystalline semi-polar GaN on Si(112), while GaN structures grown with the same growth parameters on Si(117) show four components of GaN(0002). (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

What can we learn from the endogeneization of the technical progress in GEM - E3? The case of the Kyoto protocol; Que pouvons nous apprendre de l'endogeneisation du progres technique dans GEM - E3? le cas du protocole de Kyoto

Energy Technology Data Exchange (ETDEWEB)

Fougeyrollas, A.; Le Mouel, P.; Zagame, P

2007-07-01

This project aims to study how the evaluation of the policies of fight against the greenhouse effect gases emission studied at an european scale, in the framework of the Kyoto agreements, is modified when the applied model, of general equilibrium takes into account the behavior of endogenous growth described by the new theories. More specially, the authors calibrated a production module with endogenous growth properties in the model GEM-E3. The new developed module show the costs reduction of policies of greenhouse effect gases emission limitation for France and Europe. (A.L.B.)

Optimal income taxation with endogenous human capital

NARCIS (Netherlands)

Jacobs, B.

2005-01-01

This paper augments the theory of optimal linear income taxation by taking into account human capital accumulation as a dimension of labor supply. The distribution of earning potentials is endogenous because agents differ in the ability to learn. Taxation affects utilization rates of human capital

Growth performance, carcass yield and gait score of Marshal broiler chicken reared on intensive and semi intensive management systems

Directory of Open Access Journals (Sweden)

Oluwadiya, B. O.

2017-06-01

Full Text Available The rearing system used in highly productive farms is often subjected to harsh criticism, one of the reasons being its failure to provide adequate welfare. A number of attempts have been made to introduce new technologies in rearing poultry for meat production aiming at improving rearing conditions, protecting the environment and enhancing the quality of poultry products. Given the above, one hundred and sixty eight unsexed 14-day old Marshall broiler chicks were used in a completely randomized design study to compare the effect of management systems (intensive and semi intensive on the growth performance, carcass characteristics and gait score of broiler chickens. The experiment lasted for 42 d. Data were collected on weight gain, feed intake, feed conversion ratio, carcass yield and gait score. Result showed that birds on the intensive management system recorded higher weight gain (P 0.05; 66.94%, 11.44% than those in semi-intensive system (54.55%, 10.92%, respectively. For the gait score broiler birds on semi intensive management system recorded reduced number of cases of severe and slight leg problems (P < 0.05, 25.76% vs 49.3%. It was concluded that broiler birds should be reared on intensive management system for better growth performance and carcass yield. However, birds reared on semi intensive management system had fewer leg problems compared to birds reared on intensive management system. The fewer severe leg problems observed in birds on semi intensive management system will help improve their market value thereby making birds more profitable to rear on semi intensive management system.

Microbial endogenous response to acute inhibitory impact of antibiotics.

Science.gov (United States)

Pala-Ozkok, I; Kor-Bicakci, G; Çokgör, E U; Jonas, D; Orhon, D

2017-06-13

Enhanced endogenous respiration was observed as the significant/main response of the aerobic microbial culture under pulse exposure to antibiotics: sulfamethoxazole, tetracycline and erythromycin. Peptone mixture and acetate were selected as organic substrates to compare the effect of complex and simple substrates. Experiments were conducted with microbial cultures acclimated to different sludge ages of 10 and 2 days, to visualize the effect of culture history. Evaluation relied on modeling of oxygen uptake rate profiles, reflecting the effect of all biochemical reactions associated with substrate utilization. Model calibration exhibited significant increase in values of endogenous respiration rate coefficient with all antibiotic doses. Enhancement of endogenous respiration was different with antibiotic type and initial dose. Results showed that both peptone mixture and acetate cultures harbored resistance genes against the tested antibiotics, which suggests that biomass spends cellular maintenance energy for activating the required antibiotic resistance mechanisms to survive, supporting higher endogenous decay rates. [Formula: see text]: maximum growth rate for X H (day -1 ); K S : half saturation constant for growth of X H (mg COD/L); b H : endogenous decay rate for X H (day -1 ); k h : maximum hydrolysis rate for S H1 (day -1 ); K X : hydrolysis half saturation constant for S H1 (mg COD/L); k hx : maximum hydrolysis rate for X S1 (day -1 ); K XX : hydrolysis half saturation constant for X S1 (mg COD/L); k STO : maximum storage rate of PHA by X H (day -1 ); [Formula: see text]: maximum growth rate on PHA for X H (day -1 ); K STO : half saturation constant for storage of PHA by X H (mg COD/L); X H1 : initial active biomass (mg COD/L).

Prolongation Structure of Semi-discrete Nonlinear Evolution Equations

International Nuclear Information System (INIS)

Bai Yongqiang; Wu Ke; Zhao Weizhong; Guo Hanying

2007-01-01

Based on noncommutative differential calculus, we present a theory of prolongation structure for semi-discrete nonlinear evolution equations. As an illustrative example, a semi-discrete model of the nonlinear Schroedinger equation is discussed in terms of this theory and the corresponding Lax pairs are also given.

Endogenous Cartilage Repair by Recruitment of Stem Cells.

Science.gov (United States)

Im, Gun-Il

2016-04-01

Articular cartilage has a very limited capacity for repair after injury. The adult body has a pool of stem cells that are mobilized during injury or disease. These cells exist inside niches in bone marrow, muscle, adipose tissue, synovium, and other connective tissues. A method that mobilizes this endogenous pool of stem cells will provide a less costly and less invasive alternative if these cells successfully regenerate defective cartilage. Traditional microfracture procedures employ the concept of bone marrow stimulation to regenerate cartilage. However, the regenerated tissue usually is fibrous cartilage, which has very poor mechanical properties compared to those of normal hyaline cartilage. A method that directs the migration of a large number of autologous mesenchymal stem cells toward injury sites, retains these cells around the defects, and induces chondrogenic differentiation that would enhance success of endogenous cartilage repair. This review briefly summarizes chemokines and growth factors that induce recruitment, proliferation, and differentiation of endogenous progenitor cells, endogenous cell sources for regenerating cartilage, scaffolds for delivery of bioactive factors, and bioadhesive materials that are necessary to bring about endogenous cartilage repair.

A theory of economic growth with material/energy resources and dematerialization. Interaction of three growth mechanisms

Energy Technology Data Exchange (ETDEWEB)

Ayres, Robert U. [Department of Physical Resource Theory, Chalmers Institute, Gothenburg (Sweden); Van den Bergh, Jeroen C.J.M. [Department of Spatial Economics, Faculty of Economics and Business Administration, and Institute for Environmental Studies, Free University, De Boelelaan 1105, Amsterdam 1081 HV (Netherlands)

2005-10-05

The nature of energy and material resources in a non-optimizing growth theory framework is clarified. This involves two modifications of the conventional theory. Firstly, multiple feedback mechanisms or 'growth engines' are identified, such that the impact of the cost of production through demand on growth is accounted for. Secondly, a production function distinguishes between resource use, technical efficiency, and value creation. The resulting model is analytically solved under the condition of a constant growth rate. Given model complexity, numerical experiments are performed as well, providing relevant insights to the academic and political debates on 'environmental Kuznets curves' and 'dematerialization.'.

Semi-groups of operators and some of their applications to partial differential equations

International Nuclear Information System (INIS)

Kisynski, J.

1976-01-01

Basic notions and theorems of the theory of one-parameter semi-groups of linear operators are given, illustrated by some examples concerned with linear partial differential operators. For brevity, some important and widely developed parts of the semi-group theory such as the general theory of holomorphic semi-groups or the theory of temporally inhomogeneous evolution equations are omitted. This omission includes also the very important application of semi-groups to investigating stochastic processes. (author)

Endogeneity of Money Supply: Evidence From Turkey

OpenAIRE

Oguzhan Cepni; Ibrahim Ethem Guney

2017-01-01

There is a long discussion among academics and central bankers about the theories of money supply. According to the exogenous view, central banks have the full control over money supply via policy actions including the adjustments of interest rates and reserve ratios, both of which alter commercial banks’ lending decisions. However, the theory of endogenous money supply emphasizes the role of demand for bank loans in money creation. More specifically, banks create money by meeting the demand ...

Endogenous induced technical change and the costs of Kyoto

International Nuclear Information System (INIS)

Buonanno, Paolo; Carraro, Carlo; Galeotti, M.

2001-09-01

Many predictions and conclusions in the climate change literature have been made and drawn on the basis of theoretical analyses and quantitative models that are either static or that allow for simple forms of changes in technology, often along exogenously given time paths. It is therefore not clear a priori whether those conclusions and policy recipes still hold in the more realistic case of endogenously evolving technologies. In this paper, a quantitative tool with the features of an endogenous growth model is presented, which also accounts for the possibility that technical change can be induced by environmental policy measures. Both the output production technology and the emission-output ratio depend upon the stock of knowledge, which accumulates through R and D activities. R and D is thus an additional policy variable that comes into play along with pollution abatement and capital investment. Two versions of this climate model are studied, one with endogenous technical change but exogenous environmental technical change (i.e. no induced technical change) and the other with both endogenous and induced technical change. Hence, in both models technical change evolves endogenously as far as the production technology is concerned, but endogenous environmental (or induced) technical change is only accounted for in the second version. Finally, a third version of the model also captures technological spillover effects. As an application, the three versions of the model are simulated allowing for trade of pollution permits as specified in the Kyoto Protocol and assessing the implications in terms of cost efficiency, economic growth and R and D efforts of the three different specifications of technical change

Complexity growth in massive gravity theories, the effects of chirality, and more

Science.gov (United States)

Ghodrati, Mahdis

2017-11-01

To study the effect of parity violation on the rate of complexity growth, by using "complexity=action " conjecture, we find the complexity growth rates in different solutions of the chiral theory of topologically massive gravity (TMG) and parity-preserving theory of new massive gravity (NMG). Using the results, one can see that decreasing the parameter μ , which increases the effect of the Chern-Simons term and increases chirality, would increase the rate of growth of complexity. Also one can observe a stronger correlation between complexity growth and temperature rather than complexity growth and entropy. At the end we comment on the possible meaning of the deforming term of chiral Liouville action for the rate of complexity growth of warped conformal field theories in the tensor network renormalization picture.

REFERENCES OF THE NEW THEORY OF TRADE AND ECONOMIC GROWTH

Directory of Open Access Journals (Sweden)

Spiridon Pralea

2012-12-01

Full Text Available This paper shows that the dynamization of the traditional theory of international trade through the study of growth effects on the foreign trade in the framework of neoclassical analysis, alongsidethe approach with the Keynesian toolkit of the role of foreign trade as a factor of growth, have constituted the main aspects of the new theory of trade and economic growth. The “new theory” basically represents a set of theories and models of the type “growth-led export” or “export-led growth”, which explain the complex role of foreign trade in the dynamic of development, the new segments of international trade, and also provides base for trade strategies for development. Their typology includes: “import-substitutionstrategy”, “export-promotion strategy”, and more recently “outward oriented strategy”. In the context of regionalization and globalization of competition the author believes most appropriate the states’ option for a “outward - oriented competitive development strategy”.

Endogenous growth factor stimulation of hemocyte proliferation induces resistance to Schistosoma mansoni challenge in the snail host.

Science.gov (United States)

Pila, Emmanuel A; Gordy, Michelle A; Phillips, Valerie K; Kabore, Alethe L; Rudko, Sydney P; Hanington, Patrick C

2016-05-10

Digenean trematodes are a large, complex group of parasitic flatworms that infect an incredible diversity of organisms, including humans. Larval development of most digeneans takes place within a snail (Gastropoda). Compatibility between snails and digeneans is often very specific, such that suitable snail hosts define the geographical ranges of diseases caused by these worms. The immune cells (hemocytes) of a snail are sentinels that act as a crucial barrier to infection by larval digeneans. Hemocytes coordinate a robust and specific immunological response, participating directly in parasite killing by encapsulating and clearing the infection. Hemocyte proliferation and differentiation are influenced by unknown digenean-specific exogenous factors. However, we know nothing about the endogenous control of hemocyte development in any gastropod model. Here, we identify and functionally characterize a progranulin [Biomphalaria glabrata granulin (BgGRN)] from the snail B. glabrata, a natural host for the human blood fluke Schistosoma mansoni Granulins are growth factors that drive proliferation of immune cells in organisms, spanning the animal kingdom. We demonstrate that BgGRN induces proliferation of B. glabrata hemocytes, and specifically drives the production of an adherent hemocyte subset that participates centrally in the anti-digenean defense response. Additionally, we demonstrate that susceptible B. glabrata snails can be made resistant to infection with S. mansoni by first inducing hemocyte proliferation with BgGRN. This marks the functional characterization of an endogenous growth factor of a gastropod mollusc, and provides direct evidence of gain of resistance in a snail-digenean infection model using a defined factor to induce snail resistance to infection.

A quantitative theory of solid tumor growth, metabolic rate and vascularization.

Directory of Open Access Journals (Sweden)

Alexander B Herman

Full Text Available The relationships between cellular, structural and dynamical properties of tumors have traditionally been studied separately. Here, we construct a quantitative, predictive theory of solid tumor growth, metabolic rate, vascularization and necrosis that integrates the relationships between these properties. To accomplish this, we develop a comprehensive theory that describes the interface and integration of the tumor vascular network and resource supply with the cardiovascular system of the host. Our theory enables a quantitative understanding of how cells, tissues, and vascular networks act together across multiple scales by building on recent theoretical advances in modeling both healthy vasculature and the detailed processes of angiogenesis and tumor growth. The theory explicitly relates tumor vascularization and growth to metabolic rate, and yields extensive predictions for tumor properties, including growth rates, metabolic rates, degree of necrosis, blood flow rates and vessel sizes. Besides these quantitative predictions, we explain how growth rates depend on capillary density and metabolic rate, and why similar tumors grow slower and occur less frequently in larger animals, shedding light on Peto's paradox. Various implications for potential therapeutic strategies and further research are discussed.

[Exploration of the Essence of "Endogenous Turbidity" in Chinese Medicine].

Science.gov (United States)

Fan, Xin-rong; Tang, Nong; Ji, Yun-xi; Zhang, Yao-zhong; Jiang, Li; Huang, Gui-hua; Xie, Sheng; Li, Liu-mei; Song, Chun-hui; Ling, Jiang-hong

2015-08-01

The essence of endogenous turbidity in Chinese medicine (CM) is different from cream, fat, phlegm, retention, damp, toxicity, and stasis. Along with the development of modern scientific technologies and biology, researches on the essence of endogenous turbidity should keep pace with the time. Its material bases should be defined and new connotation endowed at the microscopic level. The essence of turbidity lies in abnormal functions of zang-fu organs. Sugar, fat, protein, and other nutrient substances cannot be properly decomposed, but into semi-finished products or intermediate metabolites. They are inactive and cannot participate in normal material syntheses and decomposition. They cannot be transformed to energy metabolism, but also cannot be synthesized as executive functioning of active proteins. If they cannot be degraded by autophagy-lysosome or ubiquitin-prosome into glucose, fatty acids, amino acids, and other basic nutrients to be used again, they will accumulate inside the human body and become endogenous turbidity. Therefore, endogenous turbidity is different from final metabolites such as urea, carbon dioxide, etc., which can transform vital qi. How to improve the function of zang-fu organs, enhance its degradation by autophagy-lysosome or ubiquitin-prosome is of great significance in normal operating of zang-fu organs and preventing the emergence and progress of related diseases.

Semi-leptonic interactions

International Nuclear Information System (INIS)

Gaillard, J.M.

In spite of the presence of poorly understood strong interaction effects, the theory of hadronic currents leads to a considerable predictive power. This is shown in the discussion of the semi-leptonic decays

Endogenous Retroviruses in the Genomics Era.

Science.gov (United States)

Johnson, Welkin E

2015-11-01

Endogenous retroviruses comprise millions of discrete genetic loci distributed within the genomes of extant vertebrates. These sequences, which are clearly related to exogenous retroviruses, represent retroviral infections of the deep past, and their abundance suggests that retroviruses were a near-constant presence throughout the evolutionary history of modern vertebrates. Endogenous retroviruses contribute in myriad ways to the evolution of host genomes, as mutagens and as sources of genetic novelty (both coding and regulatory) to be acted upon by the twin engines of random genetic drift and natural selection. Importantly, the richness and complexity of endogenous retrovirus data can be used to understand how viruses spread and adapt on evolutionary timescales by combining population genetics and evolutionary theory with a detailed understanding of retrovirus biology (gleaned from the study of extant retroviruses). In addition to revealing the impact of viruses on organismal evolution, such studies can help us better understand, by looking back in time, how life-history traits, as well as ecological and geological events, influence the movement of viruses within and between populations.

A comparative assessment of endogenous water institutional change

Science.gov (United States)

Pande, Saket; Ersten, Maurits

2013-04-01

This paper builds the theory of endogenous institutional change, first proposed by Greif and Laitin (2004), for water scarce regions in context of water institutions. The current emphasis on environmental change, including hydrological change, largely ignores the adaptation of human societies to change. Humans have mostly been considered as boundary conditions or parameters of the dynamics of hydrological change and are not considered as conduits of feedbacks. Nonetheless, the dynamical representation of hydrological change with feedbacks between various components of a system is assuring since it is reminiscent of processual ecological anthropology(Orlove, 1980), except that individual decision making is absent. This paper proposes to consider selected dryland basins of the world, to conceptualize proxies of water relevant socio-economic organisation, such as spatial scales of upstream-downstream cooperation in water use, synthesized over time and then proposes a comparative assessment to test regularities predicted by an extension of river game theory (Ambec and Ehlers, 2008; van der Brink et al, 2012) to endogenous institutional change. References: Orlove, B. S. (1980). Ecological Anthropology. Annual Review of Anthropology, Vol. 9 (1980), pp. 235-273. Greif. A. and D. D. Laitin (2004). A Theory of Endogenous Institutional Change. American Political Science Review, Vol. 98, No. 4 November 2004. Ambec, S. and L. Ehlers (2008). Sharing a river amongst satiable agents. Games and Economic Behavior, 64, 35-50. Van der Brink, G. van der Laan and N. Moes (2012). Fair agreements for sharing international rivers with multiple springs and externalities. Journal of Environmental Economics and Management, 63, 388-403.

Political Ideonomy of Rostow’s Stages of Economic Growth Theory

Directory of Open Access Journals (Sweden)

M. Mozafarinia

2016-05-01

Full Text Available The conditions of success and reasons for failure of development strategies and plans, are among the most important “development studies” issues. This has been explained in different ways: for example, there is a strong relationship between the efficiency of development strategies and plans and development theories. Based on paradigmatic-implicative theory, which explains the relationship between development theories and political thought and considers the development theory as one of the practical implications of political thought, a condition for the success of development strategies and development plans can be found to be rooted in the political thought foundation. Therefore, in the present article we explore the political thought supporting Rostow’s Stages of Economic Growth theory, as one of the oldest and most important development theories which in the 1960s resulted in understanding development as “growth”. We use qualitative content analysis method to show that the political foundation of Rostow’s Stages of Economic Growth theory is based on the principle of “the most utility for the most people” in accordance with Bentham’s utilitarian political thought.

Semi-Dirac points in phononic crystals

KAUST Repository

Zhang, Xiujuan; Wu, Ying

2014-01-01

of rubber, in which the acoustic wave velocity is lower than that in water, the semi-Dirac dispersion can be characterized by an effective medium theory. The effective medium parameters link the semi-Dirac point to a topological transition in the iso

Biochemomechanical poroelastic theory of avascular tumor growth

Science.gov (United States)

Xue, Shi-Lei; Li, Bo; Feng, Xi-Qiao; Gao, Huajian

2016-09-01

Tumor growth is a complex process involving genetic mutations, biochemical regulations, and mechanical deformations. In this paper, a thermodynamics-based nonlinear poroelastic theory is established to model the coupling among the mechanical, chemical, and biological mechanisms governing avascular tumor growth. A volumetric growth law accounting for mechano-chemo-biological coupled effects is proposed to describe the development of solid tumors. The regulating roles of stresses and nutrient transport in the tumor growth are revealed under different environmental constraints. We show that the mechano-chemo-biological coupling triggers anisotropic and heterogeneous growth, leading to the formation of layered structures in a growing tumor. There exists a steady state in which tumor growth is balanced by resorption. The influence of external confinements on tumor growth is also examined. A phase diagram is constructed to illustrate how the elastic modulus and thickness of the confinements jointly dictate the steady state of tumor volume. Qualitative and quantitative agreements with experimental observations indicate the developed model is capable of capturing the essential features of avascular tumor growth in various environments.

On the theory of global population growth

International Nuclear Information System (INIS)

Kapitza, Sergei P

2010-01-01

Ours is an epoch of global demographic revolution, a time of a rapid transition from explosive population growth to a low reproduction level. This, possibly the most momentous change ever witnessed by humankind has, first and foremost, important implications for the dynamics of population. But it also affects billions of people in all aspects of their lives, and it is for this reason that demographic processes have grown into a vast problem, both globally and in Russia. Their fundamental understanding will to a large extent impact the present, the short-term future following the current critical epoch, the stable and uniform global development and its priorities, and indeed global security. Quantitative treatment of historical processes is reached using the phenomenological theory of mankind's population growth. This theory relies on the concepts and methods of physics and its conclusions should take into account the ideas of economics and genetics. (interdisciplinary physics)

Feminist theory and its influence on female entrepreneur’s growth intentions

Directory of Open Access Journals (Sweden)

Rabi Sidi Ali

2016-10-01

Full Text Available Existing results suggest that entrepreneurs vary considerably in their intentions to grow their businesses; that men have more success in pursing growth than women. Prior investigations on entrepreneurship also suggest female business owners might deliberately choose to keep their business from growing. However, these studies have been conducted in developed countries. Diversity in context and theories could vary by gender, business sectors and regions of the world. Scholars maintain that feminist perspectives theories are necessary to provide some insights in understanding the phenomena. The goal of this paper is to analyse research findings on the growth aspirations of the female entrepreneurs and offer alternative views of understanding, by employing feminist theories, in explaining why women behave differently in their adaptation of reduced growth intentions. In an attempt to understand the tendencies that might lead to reduced growth intentions in female entrepreneurship, literature was extensively reviewed on female entrepreneurship and growth intentions. The study uses a desk-based approach to data collection. An overview of the main issues concerning female entrepreneurs growth intentions is presented. The conclusions drawn from the literature provide foundations for policy measures assisting women to overcome their low growth aspirations and measures required to encourage women to grow their businesses. The paper identifies research gaps that continue to exist in female entrepreneurs growth intentions research with the aim of encouraging further research in this field.

Seismic signals of rockfalls as indicators of the origin of lava fragments emplaced during the 2010 endogenous and exogenous growth in the crater of Volcán de Colima, México

Science.gov (United States)

Zobin, Vyacheslav M.; Tellez, Armando; Aguilar, José E.; Cruz, Karla G.

2017-06-01

The 2010-2011 exogenous emplacement of a lava lobe during the 2007-2011 lava dome growth at andesitic Volcán de Colima, México, interrupted the previous endogenous regime and allowed us to obtain seismic signals associated with rockfalls triggered by both exogenous and endogenous growth. We analyzed a total of 410 seismic signals of rockfalls with durations from 50 to 150 s recorded during January-April 2010. Two characteristic populations of seismic signal peak frequencies were identified: a low frequency (LF) group (mean = 1.76 ± 0.44 Hz) and a high frequency (HF) group (mean = 3.13 ± 0.63 Hz), associated respectively with rockfalls caused by endogenous and exogenous growth in the crater. Application of the Kolmogorov-Smirnov test showed at the 0.01 significance level that the databases of LF and HF seismic signals of rockfalls belong to different groups of signals and may be considered as having different origins. The results show that the spectral properties of the seismic signals produced by rockfalls may serve as indicators of the origin of falling lava fragments and thus can be used to monitor effusive volcanic activity.

Transcriptome analysis in oak uncovers a strong impact of endogenous rhythmic growth on the interaction with plant-parasitic nematodes.

Science.gov (United States)

Maboreke, Hazel R; Feldhahn, Lasse; Bönn, Markus; Tarkka, Mika T; Buscot, Francois; Herrmann, Sylvie; Menzel, Ralph; Ruess, Liliane

2016-08-12

Pedunculate oak (Quercus robur L.), an important forest tree in temperate ecosystems, displays an endogenous rhythmic growth pattern, characterized by alternating shoot and root growth flushes paralleled by oscillations in carbon allocation to below- and aboveground tissues. However, these common plant traits so far have largely been neglected as a determining factor for the outcome of plant biotic interactions. This study investigates the response of oak to migratory root-parasitic nematodes in relation to rhythmic growth, and how this plant-nematode interaction is modulated by an ectomycorrhizal symbiont. Oaks roots were inoculated with the nematode Pratylenchus penetrans solely and in combination with the fungus Piloderma croceum, and the systemic impact on oak plants was assessed by RNA transcriptomic profiles in leaves. The response of oaks to the plant-parasitic nematode was strongest during shoot flush, with a 16-fold increase in the number of differentially expressed genes as compared to root flush. Multi-layered defence mechanisms were induced at shoot flush, comprising upregulation of reactive oxygen species formation, hormone signalling (e.g. jasmonic acid synthesis), and proteins involved in the shikimate pathway. In contrast during root flush production of glycerolipids involved in signalling cascades was repressed, suggesting that P. penetrans actively suppressed host defence. With the presence of the mycorrhizal symbiont, the gene expression pattern was vice versa with a distinctly stronger effect of P. penetrans at root flush, including attenuated defence, cell and carbon metabolism, likely a response to the enhanced carbon sink strength in roots induced by the presence of both, nematode and fungus. Meanwhile at shoot flush, when nutrients are retained in aboveground tissue, oak defence reactions, such as altered photosynthesis and sugar pathways, diminished. The results highlight that gene response patterns of plants to biotic interactions, both

'Semi-realistic'F-term inflation model building in supergravity

International Nuclear Information System (INIS)

Kain, Ben

2008-01-01

We describe methods for building 'semi-realistic' models of F-term inflation. By semi-realistic we mean that they are built in, and obey the requirements of, 'semi-realistic' particle physics models. The particle physics models are taken to be effective supergravity theories derived from orbifold compactifications of string theory, and their requirements are taken to be modular invariance, absence of mass terms and stabilization of moduli. We review the particle physics models, their requirements and tools and methods for building inflation models

Semi-classical quantization of chaotic billiards

International Nuclear Information System (INIS)

Smilansky, U.

1992-02-01

The semi-classical quantization of chaotic billiards will be developed using scattering theory approach. This will be used to introduce and explain the inherent difficulties in the semi-classical quantization of chaos, and to show some of the modern tools which were developed recently to overcome these difficulties. To this end, we shall first obtain a semi-classical secular equation which is based on a finite number of classical periodic orbits. We shall use it to derive some spectral properties, and in particular to investigate the relationship between spectral statistics of quantum chaotic systems and the predictions of random-matrix theory. We shall finally discuss an important family of chaotic billiard, whose statistics does not follow any of the canonical ensembles, (GOE,GUE,...) but rather, corresponds to a new universality class. (author)

Gene Therapy with Endogenous Inhibitors of Angiogenesis for Neovascular Age-Related Macular Degeneration: Beyond Anti-VEGF Therapy

Directory of Open Access Journals (Sweden)

Selwyn M. Prea

2015-01-01

Full Text Available Age-related macular degeneration (AMD is the leading cause of substantial and irreversible vision loss amongst elderly populations in industrialized countries. The advanced neovascular (or “wet” form of the disease is responsible for severe and aggressive loss of central vision. Current treatments aim to seal off leaky blood vessels via laser therapy or to suppress vessel leakage and neovascular growth through intraocular injections of antibodies that target vascular endothelial growth factor (VEGF. However, the long-term success of anti-VEGF therapy can be hampered by limitations such as low or variable efficacy, high frequency of administration (usually monthly, potentially serious side effects, and, most importantly, loss of efficacy with prolonged treatment. Gene transfer of endogenous antiangiogenic proteins is an alternative approach that has the potential to provide long-term suppression of neovascularization and/or excessive vascular leakage in the eye. Preclinical studies of gene transfer in a large animal model have provided impressive preliminary results with a number of transgenes. In addition, a clinical trial in patients suffering from advanced neovascular AMD has provided proof-of-concept for successful gene transfer. In this mini review, we summarize current theories pertaining to the application of gene therapy for neovascular AMD and the potential benefits when used in conjunction with endogenous antiangiogenic proteins.

Endogenous and exogenous control of ecosystem function: N cycling in headwater streams

OpenAIRE

Valett, H. M.; Thomas, S. A.; Mulholland, P. J.; Webster, J. R.; Dahm, C. N.; Fellows, C. S.; Crenshaw, C. L.; Peterson, C. G.

2008-01-01

Allochthonous inputs act as resource subsidies to many ecosystems, where they exert strong influences on metabolism and material cycling. At the same time, metabolic theory proposes endogenous thermal control independent of resource supply. To address the relative importance of exogenous and endogenous influences, we quantified spatial and temporal variation in ecosystem metabolism and nitrogen (N) uptake using seasonal releases of (15)N as nitrate in six streams differing in riparian-stream ...

Do endogenous and exogenous action control compete for perception?

Science.gov (United States)

Pfister, Roland; Heinemann, Alexander; Kiesel, Andrea; Thomaschke, Roland; Janczyk, Markus

2012-04-01

Human actions are guided either by endogenous action plans or by external stimuli in the environment. These two types of action control seem to be mediated by neurophysiologically and functionally distinct systems that interfere if an endogenously planned action suddenly has to be performed in response to an exogenous stimulus. In this case, the endogenous representation has to be deactivated first to give way to the exogenous system. Here we show that interference of endogenous and exogenous action control is not limited to motor-related aspects but also affects the perception of action-related stimuli. Participants associated two actions with contingent sensory effects in learning blocks. In subsequent test blocks, preparing one of these actions specifically impaired responding to the associated effect in an exogenous speeded detection task, yielding a blindness-like effect for arbitrary, learned action effects. In accordance with the theory of event coding, this finding suggests that action planning influences perception even in the absence of any physical similarities between action and to-be-perceived stimuli.

Endogenous Market Structures and Contract Theory. Delegation, principal-agent contracts, screening, franchising and tying

OpenAIRE

Etro Federico

2010-01-01

I study the role of unilateral strategic contracts for firms active in markets with price competition and endogenous entry. Traditional results change substantially when the market structure is endogenous rather than exogenous. They concern 1) contracts of managerial delegation to non-profit maximizers, 2) incentive principal-agent contracts in the presence of moral hazard on cost reducing activities, 3) screening contracts in case of asymmetric information on the productivity of the managers...

Monoclonal antibodies for the detection and quantitation of the endogenous plant growth regulator, abscisic acid

Energy Technology Data Exchange (ETDEWEB)

Mertens, R.; Weiler, E.W. (Bochum Univ. (Germany, F.R.). Lehrstuhl fuer Pflanzenphysiologie); Deus-Neumann, B. (Muenchen Univ. (Germany, F.R.). Inst. fuer pharmazeutische Biologie)

1983-08-22

Monoclonal antibodies (mAB) have been produced which recognize the physiologically active 2-cis-(S)-form of the endogenous plant growth regulator, abscisic acid (ABA). Cross-reaction with the ABA-catabolites, phaseic and dihydrophaseic acid, is negligible, and (R)-ABA, 2-trans-ABA, the ABA-conjugate, ABA-..beta..-D-glucopyranosyl ester, as well as the putative ABA precursor, xanthoxin, are totally unreactive. In addition to being very specific, the mAB exhibit high affinities for 2-cis-(S)-ABA; the K values were 7.9 x 10/sup 9/ l/mol and 3.7 x 10/sup 9/ l/mol for antibodies from two different clones. By mAB-radioimmunoassay (RIA), 4 pg of 2-cis-(S)-ABA (99.5% confidence level) can be detected. mAB-RIA can be used to quantitate ABA directly in unprocessed plant extracts.

Monoclonal antibodies for the detection and quantitation of the endogenous plant growth regulator, abscisic acid

International Nuclear Information System (INIS)

Mertens, R.; Weiler, E.W.; Deus-Neumann, B.

1983-01-01

Monoclonal antibodies (mAB) have been produced which recognize the physiologically active 2-cis-(S)-form of the endogenous plant growth regulator, abscisic acid (ABA). Cross-reaction with the ABA-catabolites, phaseic and dihydrophaseic acid, is negligible, and (R)-ABA, 2-trans-ABA, the ABA-conjugate, ABA-β-D-glucopyranosyl ester, as well as the putative ABA precursor, xanthoxin, are totally unreactive. In addition to being very specific, the mAB exhibit high affinities for 2-cis-(S)-ABA; the K values were 7.9 x 10 9 l/mol and 3.7 x 10 9 l/mol for antibodies from two different clones. By mAB-radioimmunoassay (RIA), 4 pg of 2-cis-(S)-ABA (99.5% confidence level) can be detected. mAB-RIA can be used to quantitate ABA directly in unprocessed plant extracts. (Auth.)

Thermoelectric properties of fully hydrogenated graphene: Semi-classical Boltzmann theory

International Nuclear Information System (INIS)

Reshak, A. H.

2015-01-01

Based on the calculated band structure, the electronic transport coefficients of chair-/boat-like graphane were evaluated by using the semi-classical Boltzmann theory and rigid band model. The maximum value of electrical conductivity for chair (boat)-like graphane of about 1.4 (0.6) × 10 19 (Ωms) −1 is achieved at 600 K. The charge carrier concentration and the electrical conductivity linearly increase with increasing the temperature in agreement with the experimental work for graphene. The investigated materials exhibit the highest value of Seebeck coefficient at 300 K. We should emphasize that in the chemical potential between ∓0.125 μ(eV) the investigated materials exhibit minimum value of electronic thermal conductivity, therefore, maximum efficiency. As the temperature increases, the electronic thermal conductivity increases exponentially, in agreement with the experimental data of graphene. We also calculated the power factor of chair-/boat-like graphane at 300 and 600 K as a function of chemical potential between ∓0.25 μ(eV)

Evidence for endogenous opioid release in the amygdala during positive emotion.

Science.gov (United States)

Koepp, M J; Hammers, A; Lawrence, A D; Asselin, M C; Grasby, P M; Bench, C J

2009-01-01

Endogenous opioid release has been linked to relief from aversive emotional memories, thereby promoting a euphoric state and subsequent interactions towards social stimuli resulting in the formation of social preferences. However, this theory remains controversial. Using positron emission tomography and [(11)C]diprenorphine (DPN) in healthy volunteers, we found significantly reduced DPN binding to opioid receptor in the hippocampus during positive mood induction compared to neutral mood. Furthermore, the magnitude of positive mood change correlated negatively with DPN binding in the amygdala bilaterally. Our finding of reduced DPN binding is consistent with increased release of endogenous opioids, providing direct evidence that localised release of endogenous opioids is involved in the regulation of positive emotion in humans.

Two-velocity elasticity theory and facet growth

OpenAIRE

Andreev, A. F.; Melnikovsky, L. A.

2002-01-01

We explain the linear growth of smooth solid helium facets by the presence of lattice point defects. To implement this task, the framework of very general two-velocity elasticity theory equations is developed. Boundary conditions for these equations for various surface types are derived. We also suggest additional experiments to justify the concept.

Endogenous induced technical change and the costs of Kyoto

International Nuclear Information System (INIS)

Buonanno, Paolo; Carraro, Carlo; Galeotti, Marzio

2003-01-01

We present a model for climate change policy analysis which accounts for the possibility that technology evolves endogenously and that technical change can be induced by environmental policy measures. Both the output production technology and the emission-output ratio depend upon a stock of knowledge, which accumulates through R and D activities. Two versions of this model are studied, one with endogenous technical change but exogenous environmental technical change and the other with both endogenous and induced technical change. A third version also captures technological spillover effects. As an application, the model is simulated allowing for trade of pollution permits as specified in the Kyoto Protocol and assessing the implications in terms of cost efficiency, economic growth and R and D efforts of the three different specifications of technical change

Implicit Theories about Intelligence and Growth (Personal Best) Goals: Exploring Reciprocal Relationships

Science.gov (United States)

Martin, Andrew J.

2015-01-01

Background: There has been increasing interest in growth approaches to students' academic development, including value-added models, modelling of academic trajectories, growth motivation orientations, growth mindsets, and growth goals. Aims: This study sought to investigate the relationships between implicit theories about intelligence…

Are endogenous feline leukemia viruses really endogenous?

Science.gov (United States)

Stewart, H; Jarrett, O; Hosie, M J; Willett, B J

2011-10-15

Full length endogenous feline leukemia virus (FeLV) proviruses exist within the genomes of many breeds of domestic cat raising the possibility that they may also exist in a transmissible exogenous form. Such viruses would share receptor usage with the recombinant FeLV-B subgroup, a viral subgroup that arises in vivo by recombination between exogenous subgroup A virus (FeLV-A) and endogenous FeLV. Accordingly, all isolates of FeLV-B made to date have contained a "helper" FeLV-A, consistent with their recombinatorial origin. In order to assess whether endogenous viruses are transmitted between cats, we examined primary isolates of FeLV for which the viral subgroup had been determined for the presence of a subgroup B virus that lacked an FeLV-A. Here we describe the identification of two primary field isolates of FeLV (2518 and 4314) that appeared to contain subgroup B virus only by classical interference assays, raising the possibility of between-host transmission of endogenous FeLV. Sequencing of the env gene and U3 region of the 3' long terminal repeat (LTR) confirmed that both viral genomes contained endogenous viral env genes. However the viral 3' LTRs appeared exogenous in origin with a putative 3' recombination breakpoint residing at the 3' end of the env gene. Further, the FeLV-2518 virions also co-packaged a truncated FeLV-A genome containing a defective env gene, termed FeLV-2518(A) whilst no helper subgroup A viral genome was detected in virions of FeLV-4314. The acquisition of an exogenous LTR by the endogenous FeLV in 4314 may have allowed a recombinant FeLV variant to outgrow an exogenous FeLV-A virus that was presumably present during first infection. Given time, a similar evolution may also occur within the 2518 isolate. The data suggest that endogenous FeLVs may be mobilised by acquisition of exogenous LTRs yielding novel viruses that type biologically as FeLV-B. Copyright © 2011 Elsevier B.V. All rights reserved.

Money, banks and endogenous volatility

OpenAIRE

Pere Gomis-Porqueras

2000-01-01

In this paper I consider a monetary growth model in which banks provide liquidity, and the government fixes a constant rate of money creation. There are two underlying assets in the economy, money and capital. Money is dominated in rate of return. In contrast to other papers with a larger set of government liabilities, I find a unique equilibrium when agents' risk aversion is moderate. However, indeterminacies and endogenous volatility can be observed when agents are relatively risk averse.

Endogenous antipyretics.

Science.gov (United States)

Roth, Joachim

2006-09-01

The febrile increase of body temperature is regarded as a component of the complex host response to infection or inflammation that accompanies the activation of the immune system. Late phases of fever appear mediated by pro-inflammatory cytokines called endogenous pyrogens. The rise of body temperature is beneficial because it accelerates several components of the activated immune system. To prevent an excessive and dangerous rise of body temperature the febrile response is controlled, limited in strength and duration, and sometimes even prevented by the actions of endogenous antipyretic substances liberated systemically or within the brain during fever. In most cases the antipyretic effects are achieved by an inhibitory influence on the formation or action of endogenous pyrogens, or by effects on neuronal thermoregulatory circuits that are activated during fever. Endogenous antipyretic substances include steroid hormones, neuropeptides, cytokines and other molecules. It is the purpose of this review to consider the current state in the research on endogenous antipyretic systems.

Growth of the firm and foreign trade: Adrian Wood's theory revisited

OpenAIRE

Catermol, Fabrício

2006-01-01

This paper analyzes the growth of the firm by foreign trade. The theory of Adrian Wood is revisited for the analysis of growth and profit trade-off and improved to cope with growth by exports. The main outcome of this paper is that low domestic demand can be a very important factor to firm choices growth by foreign market. However, the growth of domestic demand does not necessarily reduce exports.

Technical conditions for sustainable growth in economic theory. An analysis

International Nuclear Information System (INIS)

Granda C, Catalina

2008-01-01

Economic theory and its models point out returns to scale, substitution among productive factors and technological progress as conditions for sustainable growth. This work aims at a critical appraisal of these conditions, particularly the ones related to substitution between natural resources and manmade capital and technical change, by recognizing the inevitable physical scarcity of resources concomitant to the human actions in a world governed by hemodynamic restrictions. To do so, the role that the mentioned conditions play in the theories of economic growth with resources is analyzed, and its limitations and objections from a biophysical perspective are indicated as well. Finally, a brief consideration as to how inappropriate the theoretical representations of economic activities are to take account of growth in spite of resource exhaustion or degradation is carried out

The Demand for Endogenous Money: A Lesson in Institutional Change

OpenAIRE

Peter Howells

2007-01-01

During a distinguished career, Basil Moore has made numerous important contributions to macroeconomics and monetary economics, and is renowned as the progenitor of the ‘horizontalist’ analysis of endogenous money. More recently, he has embraced complexity theory as part of an ongoing effort to understand macroeconomics as an evolving, path-dependent process. This book celebrates and explores Basil Moore’s interests in and contributions to monetary and macroeconomic theory.

ELABELA Is an Endogenous Growth Factor that Sustains hESC Self-Renewal via the PI3K/AKT Pathway.

Science.gov (United States)

Ho, Lena; Tan, Shawn Y X; Wee, Sheena; Wu, Yixuan; Tan, Sam J C; Ramakrishna, Navin B; Chng, Serene C; Nama, Srikanth; Szczerbinska, Iwona; Sczerbinska, Iwona; Chan, Yun-Shen; Avery, Stuart; Tsuneyoshi, Norihiro; Ng, Huck Hui; Gunaratne, Jayantha; Dunn, N Ray; Reversade, Bruno

2015-10-01

ELABELA (ELA) is a peptide hormone required for heart development that signals via the Apelin Receptor (APLNR, APJ). ELA is also abundantly secreted by human embryonic stem cells (hESCs), which do not express APLNR. Here we show that ELA signals in a paracrine fashion in hESCs to maintain self-renewal. ELA inhibition by CRISPR/Cas9-mediated deletion, shRNA, or neutralizing antibodies causes reduced hESC growth, cell death, and loss of pluripotency. Global phosphoproteomic and transcriptomic analyses of ELA-pulsed hESCs show that it activates PI3K/AKT/mTORC1 signaling required for cell survival. ELA promotes hESC cell-cycle progression and protein translation and blocks stress-induced apoptosis. INSULIN and ELA have partially overlapping functions in hESC medium, but only ELA can potentiate the TGFβ pathway to prime hESCs toward the endoderm lineage. We propose that ELA, acting through an alternate cell-surface receptor, is an endogenous secreted growth factor in human embryos and hESCs that promotes growth and pluripotency. Copyright © 2015 Elsevier Inc. All rights reserved.

Nanowire growth from the viewpoint of the thin film polylayer growth theory

Science.gov (United States)

Kashchiev, Dimo

2018-03-01

The theory of polylayer growth of thin solid films is employed for description of the growth kinetics of single-crystal nanowires. Expressions are derived for the dependences of the height h and radius r of a given nanowire on time t, as well as for the h(r) dependence. These dependences are applicable immediately after the nanowire nucleation on the substrate and thus include the period during which the nucleated nanowire changes its shape from that of cap to that of column. The analysis shows that the nanowire cap-to-column shape transition is continuous and makes it possible to kinetically define the nanowire shape-transition radius by means of the nanowire radial and axial growth rates. The obtained h(t), r(t) and h(r) dependences are found to provide a good description of available experimental data for growth of self-nucleated GaN nanowires by the vapor-solid mechanism.

The overexpression of insect endogenous small RNAs in transgenic rice inhibits growth and delays pupation of striped stem borer (Chilo suppressalis).

Science.gov (United States)

Jiang, Shan; Wu, Hao; Liu, Haoju; Zheng, Jie; Lin, Yongjun; Chen, Hao

2017-07-01

The striped stem borer (SSB), Chilo suppressalis Walker, is a major rice insect pest worldwide. RNA interference (RNAi) has become a promising strategy for developing insect-resistant crops. In a previous study, five double-stranded RNAs (dsRNAs) targeting important SSB housekeeping genes were overexpressed in rice, but none of the acquired dsRNA-transgenic rice plants showed significant effects on SSB. Thirteen selected SSB endogenous small RNAs, predicted as SSB novel microRNAs (miRNAs), were overexpressed in rice using artificial miRNA (amiRNA) expression technology. Feeding tests showed that two out of 13 selected SSB novel miRNAs caused significant growth inhibition for feeding SSB larvae based on transgenic rice expression. Pupation was delayed 4 days when SSB larvae consecutively fed on transgenic rice expressing the SSB novel miRNA candidate csu-novel-miR15 (csu-15 rice). Gene expression analysis confirmed that the expression levels of at least six SSB unigenes significantly changed (i.e., were up- or down-regulated) after feeding on csu-15 rice. Our research demonstrated a novel RNAi strategy using SSB endogenous small RNAs to develop RNAi crops for pest management; this strategy is different from the common RNAi resulting from transgenic dsRNAs or amiRNAs targeting certain insect endogenous genes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Evidence that platelet-derived growth factor may be a novel endogenous pyrogen in the central nervous system.

Science.gov (United States)

Pelá, I R; Ferreira, M E; Melo, M C; Silva, C A; Coelho, M M; Valenzuela, C F

2000-05-01

Platelet-derived growth factor (PDGF) exerts neurotrophic and neuromodulatory actions in the mammalian central nervous system (CNS). Like the cytokines, PDGF primarily signals through tyrosine phosphorylation-dependent pathways that activate multiple intracellular molecules including Janus family kinases. We previously showed that microinjection of PDGF-BB into the lateral ventricle induced a febrile response in rats that was reduced by pretreatment with Win 41662, a potent inhibitor of PDGF receptors (Pelá IR, Ferreira MES, Melo MCC, Silva CAA, and Valenzuela CF. Ann NY Acad Sci 856: 289-293, 1998). In this study, we further characterized the role of PDGF-BB in the febrile response in rats. Microinjection of PDGF-BB into the third ventricle produced a dose-dependent increase in colonic temperature that peaked 3-4 h postinjection. Win 41662 attenuated fever induced by intraperitoneal injection of bacterial lipopolysaccharide, suggesting that endogenous PDGF participates in the febrile response to this exogenous pyrogen. Importantly, febrile responses induced by tumor necrosis factor-alpha, interleukin-1beta, and interleukin-6 were unchanged by Win 41662. Both indomethacin and dexamethasone blocked the PDGF-BB-induced increase in colonic temperature, and, therefore, we postulate that PDGF-BB may act via prostaglandin- and/or inducible enzyme-dependent pathways. Thus our findings suggest that PDGF-BB is an endogenous CNS mediator of the febrile response in rats.

Borderline Personality Disorder: A Dysregulation of the Endogenous Opioid System?

Science.gov (United States)

Bandelow, Borwin; Schmahl, Christian; Falkai, Peter; Wedekind, Dirk

2010-01-01

The neurobiology of borderline personality disorder (BPD) remains unclear. Dysfunctions of several neurobiological systems, including serotoninergic, dopaminergic, and other neurotransmitter systems, have been discussed. Here we present a theory that alterations in the sensitivity of opioid receptors or the availability of endogenous opioids…

Some aspects of non-linear semi-groups

International Nuclear Information System (INIS)

Plant, A.T.

1976-01-01

Some simpler theorems in the theory of non-linear semi-groups of non-reflexive Banach spaces are proved, with the intention to introduce the reader to this active field of research. Flow invariance, in particular for Lipschitz generators, and contraction semi-groups are discussed in some detail. (author)

Values of Land and Renewable Resources in a Three-Sector Economic Growth Model

Directory of Open Access Journals (Sweden)

Zhang Wei-Bin

2015-04-01

Full Text Available This paper studies dynamic interdependence of capital, land and resource values in a three sector growth model with endogenous wealth and renewable resources. The model is based on the neoclassical growth theory, Ricardian theory and growth theory with renewable resources. The household’s decision is modeled with an alternative approach proposed by Zhang two decades ago. The economic system consists of the households, industrial, agricultural, and resource sectors. The model describes a dynamic interdependence between wealth accumulation, resource change, and division of labor under perfect competition. We simulate the model to demonstrate the existence of a unique stable equilibrium point and plot the motion of the dynamic system. The study conducts comparative dynamic analysis with regard to changes in the propensity to consume resources, the propensity to consume housing, the propensity to consume agricultural goods, the propensity to consume industrial goods, the propensity to save, the population, and the output elasticity of capital of the resource sector.

Endogenous money, circuits and financialization

OpenAIRE

Malcolm Sawyer

2013-01-01

This paper locates the endogenous money approach in a circuitist framework. It argues for the significance of the credit creation process for the evolution of the economy and the absence of any notion of ‘neutrality of money’. Clearing banks are distinguished from other financial institutions as the providers of initial finance in a circuit whereas other financial institutions operate in a final finance circuit. Financialization is here viewed in terms of the growth of financial assets an...

The endogenous plant hormones and ratios regulate sugar and dry matter accumulation in Jerusalem artichoke in salt-soil.

Science.gov (United States)

Li, Lingling; Shao, Tianyun; Yang, Hui; Chen, Manxia; Gao, Xiumei; Long, Xiaohua; Shao, Hongbo; Liu, Zhaopu; Rengel, Zed

2017-02-01

The changes in content of endogenous hormones in stolons and tubers of Jerusalem artichoke (Helianthus tuberosus L.) regulate tuber growth, but the specific knowledge about the importance of balance among the endogenous hormones is lacking. Two varieties of Jerusalem artichoke (NY-1 and QY-2) were tested for the endogenous zeatin (ZT), auxins (IAA), gibberellins (GA 3 ) and abscisic acid (ABA) in regulating sugar and dry matter accumulation in tubers. The dry matter content and sugar accumulation in tubers were correlated positively with endogenous ZT and negatively with GA 3 content and GA 3 /ABA and IAA/ABA content ratios. Throughout the tuber formation, ZT content was higher in NY-1 than QY-2 tubers, whereas ABA content was higher in QY-2 than NY-1 tubers. The content ratios GA 3 /ABA and IAA/ABA were greater in NY-1 than QY-2 before tuber initiation, but QY-2 surpassed NY-1 during the tuber growth stage. The GA 3 /ABA and IAA/ABA content ratios declined during tuber growth. The results suggested that a dynamic balance of endogenous hormones played an important role in tuber development. Copyright © 2016 Elsevier B.V. All rights reserved.

Growth of semi-insulating InP through nuclear doping

International Nuclear Information System (INIS)

Aliyev, M.I; Rashidova, Sh.Sh; Huseynli, M.A.

2012-01-01

Full text : Semi-insulating semiconductors are widely used in so-called dielectronics. Dielectric devices have quick response, good frequency characteristics, a low noise level, low sensitivity to temperature changes, etc. One of the most promising semiconductor materials is InP. At present annealing and doping are commonly used techniques to grow semi-insulating InP. The aim of this work was to grow semi-insulating InP through nuclear doping (by irradiation with gamma-quanta). InP single crystals were obtained by Czochralski method. Specimens were irradiated with doses of 10kGr at room temperature. Electrical conductivity and Hall effect were measured before and after irradiation in the temperature range 77 to 320K. After irradiation reduction in electrical conductivity was observed. This fact can be associated with formation of M-centers in positively threefold charged states of vacancy and antisite defects. Under irradiation first Ini interstitial atoms and phosphorus vacancies form. Further, the Ini atoms occupy the phosphorus vacancies. As a result there appear InP antiste defects, which along with indium vacancies form V I nI n p + In p + + complexes of the acceptor type. These complexes turn out to be traps for charge carriers and electrical conductivity of irradiated InP are sharply reduced to semi-insulating specimens

Growth theory after Keynes, part I: the unfortunate suppression of the Harrod-Domar model

Directory of Open Access Journals (Sweden)

Hendrik Van den Berg

2013-11-01

Full Text Available After Harrod and Domar independently developed a dynamic Keynesian circular flow model to illustrate the instability of a growing economy, mainstream economists quickly reduced their model to a supply side-only growth model, which they subsequently rejected as too simplistic and replaced with Solow’s neoclassical growth model. The rejection process of first diminishing the model and then replaced it with a neoclassical alternative was similar to how the full Keynesian macroeconomic paradigm was diminished into IS-LM analysis and then replaced by a simplistic neoclassical framework that largely ignored the demand side of the economy. Furthermore, subsequent work by mainstream economists has resulted in a logically inconsistent framework for analyzing economic growth; the popular endogenous growth models, which use Schumpeter’s concept of profit-driven creative destruction to explain the technological change that Solow left as exogenous, are not logically compatible with the Solow model.

Semi-Dirac points in phononic crystals

KAUST Repository

Zhang, Xiujuan

2014-01-01

A semi-Dirac cone refers to a peculiar type of dispersion relation that is linear along the symmetry line but quadratic in the perpendicular direction. It was originally discovered in electron systems, in which the associated quasi-particles are massless along one direction, like those in graphene, but effective-mass-like along the other. It was reported that a semi-Dirac point is associated with the topological phase transition between a semi-metallic phase and a band insulator. Very recently, the classical analogy of a semi-Dirac cone has been reported in an electromagnetic system. Here, we demonstrate that, by accidental degeneracy, two-dimensional phononic crystals consisting of square arrays of elliptical cylinders embedded in water are also able to produce the particular dispersion relation of a semi-Dirac cone in the center of the Brillouin zone. A perturbation method is used to evaluate the linear slope and to affirm that the dispersion relation is a semi-Dirac type. If the scatterers are made of rubber, in which the acoustic wave velocity is lower than that in water, the semi-Dirac dispersion can be characterized by an effective medium theory. The effective medium parameters link the semi-Dirac point to a topological transition in the iso-frequency surface of the phononic crystal, in which an open hyperbola is changed into a closed ellipse. This topological transition results in drastic change in wave manipulation. On the other hand, the theory also reveals that the phononic crystal is a double-zero-index material along the x-direction and photonic-band-edge material along the perpendicular direction (y-direction). If the scatterers are made of steel, in which the acoustic wave velocity is higher than that in water, the effective medium description fails, even though the semi-Dirac dispersion relation looks similar to that in the previous case. Therefore different wave transport behavior is expected. The semi-Dirac points in phononic crystals described in

Measurement of endogenous allergens in genetically modified soybeans--short communication.

Science.gov (United States)

Ladics, Gregory S; Budziszewski, Gregory J; Herman, Rod A; Herouet-Guicheney, Corinne; Joshi, Saurabh; Lipscomb, Elizabeth A; McClain, Scott; Ward, Jason M

2014-10-01

The measurement of endogenous allergens is required by the European Commission (EC) as part of the compositional analysis for GM products from host plants that are common causes of food allergy, such as soybean (EC Implementing Regulation No. 503/2013). In each case, the EC Implementing Regulation indicates that analysis be conducted on identified allergens as specified in the Organization of Economic Cooperation and Development (OECD) consensus documents on compositional considerations for new plant varieties. This communication discusses the methods available to measure endogenous allergens as well as the endogenous soybean allergens that should be analyzed. It is suggested herein that in conjunction with the 2012 OECD consensus document on soybean, any list of soybean allergens should be based on clinically relevant data among publicly available allergen databases and peer-reviewed scientific publications, and the ability to measure the identified allergen. Based on a detailed analysis of the scientific literature, the following key points are recommended: (1) the acceptance of serum-free, quantitative analytical method data as an alternative to traditional IgE reactivity qualitative or semi-quantitative data for evaluation of endogenous soybean allergen content; (2) eight of the 15 potential allergens listed in the OECD soybean consensus document (Gly m 3, Gly m 4, Gly m Bd28K, Gly m Bd30K, Gly m 5, Gly m 6, Gly m 8, and Kunitz trypsin inhibitor) have both appropriate supporting clinical data and sufficient sequence information to be evaluated in comparative endogenous soybean allergen studies; and (3) the remaining seven proteins (Gly m 1, Gly m 2, unknown 50kDa protein, unknown 39kDa protein, P-22-25, lipoxygenase and lectin) lack sufficient data for clear classification as confirmed allergens and/or available sequence information and should not be currently included in the measurement of endogenous soybean allergens in the compositional analysis for the EU

Effects of temperature on embryonic and larval development and growth in the natterjack toad (Bufo calamita in a semi-arid zone

Directory of Open Access Journals (Sweden)

Sanuy, D.

2008-06-01

Full Text Available Temperature affects the duration of embryonic and larval periods in amphibians. Plasticity in time to metamorphosis is especially important in amphibian populations of Mediterranean semi-arid zones where temperatures are high and precipitation is low, increasing the rate of pond desiccation. In order to test the influence of water temperature on the larval development and growth of the natterjack toad (Bufo calamita, we collected two spawns in a semi¿arid zone at Balaguer (Lleida, NE Iberian peninsula. Approximately 50 (+/-10 eggs (stage 14-16 were raised in the lab at different temperature conditions: 10, 15, 20, 22.5 and 25ºC with 12:12 photoperiod. The results show a lengthening of development time with decreasing temperatures and a better survival performance of B. calamita to high temperatures. However, mean size at metamorphosis was not different across treatments, thus, suggesting that this population of B. calamita requires a minimum size to complete the metamorphosis. This study is the first approach to examine the effects that climatic factors have on the growth and development of B. calamita in semi-arid zones.

Increasing Goat Productivity Through the Improvement of Endogenous Secretion of Pregnant Hormones Using Follicle Stimulating Hormone

Directory of Open Access Journals (Sweden)

Andriyanto Andriyanto

2011-05-01

Full Text Available Abstract. Previous studies reported that the improvement of endogenous estrogen and progesterone secretions during gestation improved fetal prenatal growth, birth weight, mammary gland growth and development, milk production, litter size, pre- and post-weaning growths. An experiment was conducted to apply the improvement of endogenous secretion of pregnant hormones during pregnancy to increase goat productivity. Thirty-six female ettawah-cross does were divided into 2 groups. Group 1 (control: 18 does included does without improvement of endogenous secretion of pregnant hormones and Group 2 (treatment: 18 does included does with improvement of endogenous secretion of pregnant hormones using follicle stimulating hormones to stimulate super ovulation. The application of this technology increased total offspring born (control: 25 offspring; treatment: 42 offspring, average litter size (control: 1.88; treatment: 2.33, offspring birth weight (control: 2.85±0.50 kg; treatment: 3.82±0.40 kg, and does milk production (control: 1.36±0.34 L/does/day; treatment: 2.10±0.21 L/does/day. Offspring born to does with improved endogenous secretion of pregnant hormones had better weaning weight (control: 11.17±1.99 kg/offspring; treatment: 14.5±1.11 kg/offspring. At weaning period, does with improved endogenous secretion of pregnant hormones produced offspring with total weaning weight twice as heavy as control does (control: 189.9 kg; treatment: 403.6 kg. By a simple calculation of economic analysis, this technology application could increase gross revenue per does until weaning by Rp. 432.888,89. It was concluded that this technology is economically feasible to be applied in small-scale farm. Key Words: follicle stimulating hormone, pregnant hormones, endogenous secretion, super ovulation, ettawah-cross does

Green's functions for theories with massless particles (in perturbation theory). [Growth properties, momentum space, mass renormalization

Energy Technology Data Exchange (ETDEWEB)

Blanchard, P [European Organization for Nuclear Research, Geneva (Switzerland); Seneor, R [European Organization for Nuclear Research, Geneva (Switzerland); Ecole Polytechnique, 75 - Paris (France). Centre de Physique Theorique)

1975-01-01

With the method of perturbative renormalization developed by Epstein and Glaser it is shown that Green's functions exist for theories with massless particles such as Q.E.D. and lambda:PHI/sup 2n/ theories. Growth properties are given in momentum space. In the case of Q.E.D., it is also shown that one can perform the physical mass renormalization.

Pharmacokinetic-pharmacodynamic analysis of antipsychotics-induced extrapyramidal symptoms based on receptor occupancy theory incorporating endogenous dopamine release.

Science.gov (United States)

Matsui-Sakata, Akiko; Ohtani, Hisakazu; Sawada, Yasufumi

2005-06-01

We aimed to analyze the risks of extrapyramidal symptoms (EPS) induced by typical and atypical antipsychotic drugs using a common pharmacokinetic-pharmacodynamic (PK-PD) model based on the receptor occupancy. We collected the data for EPS induced by atypical antipsychotics, risperidone, olanzapine and quetiapine, and a typical antipsychotic, haloperidol from literature and analyzed the following five indices of EPS, the ratio of patients obliged to take anticholinergic medication, the occurrence rates of plural extrapyramidal symptoms (more than one of tremor, dystonia, hypokinesia, akathisia, extrapyramidal syndrome, etc.), parkinsonism, akathisia, and extrapyramidal syndrome. We tested two models, i.e., a model incorporating endogenous dopamine release owing to 5-HT2A receptor inhibition and a model not considering the endogenous dopamine release, and used them to examine the relationship between the D2 receptor occupancy of endogenous dopamine and the extent of drug-induced EPS. The model incorporating endogenous dopamine release better described the relationship between the mean D2 receptor occupancy of endogenous dopamine and the extent of EPS than the other model, as assessed by the final sum of squares of residuals (final SS) and Akaike's Information Criteria (AIC). Furthermore, the former model could appropriately predict the risks of EPS induced by two other atypical antipsychotics, clozapine and ziprasidone, which were not incorporated into the model development. The developed model incorporating endogenous dopamine release owing to 5-HT2A receptor inhibition may be useful for the prediction of antipsychotics-induced EPS.

In situ tissue regeneration: chemoattractants for endogenous stem cell recruitment.

Science.gov (United States)

Vanden Berg-Foels, Wendy S

2014-02-01

Tissue engineering uses cells, signaling molecules, and/or biomaterials to regenerate injured or diseased tissues. Ex vivo expanded mesenchymal stem cells (MSC) have long been a cornerstone of regeneration therapies; however, drawbacks that include altered signaling responses and reduced homing capacity have prompted investigation of regeneration based on endogenous MSC recruitment. Recent successful proof-of-concept studies have further motivated endogenous MSC recruitment-based approaches. Stem cell migration is required for morphogenesis and organogenesis during development and for tissue maintenance and injury repair in adults. A biomimetic approach to in situ tissue regeneration by endogenous MSC requires the orchestration of three main stages: MSC recruitment, MSC differentiation, and neotissue maturation. The first stage must result in recruitment of a sufficient number of MSC, capable of effecting regeneration, to the injured or diseased tissue. One of the challenges for engineering endogenous MSC recruitment is the selection of effective chemoattractant(s). The objective of this review is to synthesize and evaluate evidence of recruitment efficacy by reported chemoattractants, including growth factors, chemokines, and other more recently appreciated MSC chemoattractants. The influence of MSC tissue sources, cell culture methods, and the in vitro and in vivo environments is discussed. This growing body of knowledge will serve as a basis for the rational design of regenerative therapies based on endogenous MSC recruitment. Successful endogenous MSC recruitment is the first step of successful tissue regeneration.

Endogenous growth hormone and insulin after interposition of a reversed jejunal segment in short bowel syndrome. An experimental study on pigs

Directory of Open Access Journals (Sweden)

Papamichail Michail

2012-08-01

Full Text Available Abstract Background Interposition of a reversed jejunal loop in short bowel sydrome has previously been investigated in human along with animal models and seemed able to facilitate intestinal adaptation. However, it is unclear if growth hormone and insulin, well known for their implication in short bowel pathophysiology, intervene on this effect. Findings Porcine models were randomly allocated to two cohorts: (1 short bowel (SB group (n = 8 and (2 short bowel reverse jejunal segment (SB-RS group (n = 8. Amongst other parameters serum growth hormone and insulin were measured at baseline, as well as on postoperative day 30 and 60. Conclusion Both endogenous hormones failed to demonstrate significant difference in respect to potential direct effect to mechanisms of enhanced intestinal adaptation in reversed group

Analysis of the neutrons dispersion in a semi-infinite medium based in transport theory and the Monte Carlo method

International Nuclear Information System (INIS)

Arreola V, G.; Vazquez R, R.; Guzman A, J. R.

2012-10-01

In this work a comparative analysis of the results for the neutrons dispersion in a not multiplicative semi-infinite medium is presented. One of the frontiers of this medium is located in the origin of coordinates, where a neutrons source in beam form, i.e., μο=1 is also. The neutrons dispersion is studied on the statistical method of Monte Carlo and through the unidimensional transport theory and for an energy group. The application of transport theory gives a semi-analytic solution for this problem while the statistical solution for the flow was obtained applying the MCNPX code. The dispersion in light water and heavy water was studied. A first remarkable result is that both methods locate the maximum of the neutrons distribution to less than two mean free trajectories of transport for heavy water, while for the light water is less than ten mean free trajectories of transport; the differences between both methods is major for the light water case. A second remarkable result is that the tendency of both distributions is similar in small mean free trajectories, while in big mean free trajectories the transport theory spreads to an asymptote value and the solution in base statistical method spreads to zero. The existence of a neutron current of low energy and toward the source is demonstrated, in contrary sense to the neutron current of high energy coming from the own source. (Author)

TOPICAL PROBLEMS: The phenomenological theory of world population growth

Science.gov (United States)

Kapitza, Sergei P.

1996-01-01

Of all global problems world population growth is the most significant. Demographic data describe this process in a concise and quantitative way in its past and present. Analysing this development it is possible by applying the concepts of systems analysis and synergetics, to work out a mathematical model for a phenomenological description of the global demographic process and to project its trends into the future. Assuming self-similarity as the dynamic principle of development, growth can be described practically over the whole of human history, assuming the growth rate to be proportional to the square of the number of people. The large parameter of the theory and the effective size of a coherent population group is of the order of 105 and the microscopic parameter of the phenomenology is the human lifespan. The demographic transition — a transition to a stabilised world population of some 14 billion in a foreseeable future — is a systemic singularity and is determined by the inherent pattern of growth of an open system, rather than by the lack of resources. The development of a quantitative nonlinear theory of the world population is of interest for interdisciplinary research in anthropology and demography, history and sociology, for population genetics and epidemiology, for studies in evolution of humankind and the origin of man. The model also provides insight into the stability of growth and the present predicament of humankind, and provides a setting for discussing the main global problems.

Extravascular red blood cells and hemoglobin promote tumor growth and therapeutic resistance as endogenous danger signals.

Science.gov (United States)

Yin, Tao; He, Sisi; Liu, Xiaoling; Jiang, Wei; Ye, Tinghong; Lin, Ziqiang; Sang, Yaxiong; Su, Chao; Wan, Yang; Shen, Guobo; Ma, Xuelei; Yu, Min; Guo, Fuchun; Liu, Yanyang; Li, Ling; Hu, Qiancheng; Wang, Yongsheng; Wei, Yuquan

2015-01-01

Hemorrhage is a common clinical manifestation in patients with cancer. Intratumor hemorrhage has been demonstrated to be a poor prognostic factor for cancer patients. In this study, we investigated the role of RBCs and hemoglobin (Hb) in the process of tumor progression and therapeutical response. RBCs and Hb potently promoted tumor cell proliferation and syngenic tumor growth. RBCs and Hb activated the reactive oxygen species-NF-κB pathway in both tumor cells and macrophages. RBCs and Hb also induced chemoresistance mediated, in part, by upregulating ABCB1 gene expression. Tumor growth induced by RBCs was accompanied by an inflammatory signature, increased tumor vasculature, and influx of M2 macrophages. In both the peritoneal cavity and tumor microenvironment, extravascular RBCs rapidly recruited monocyte-macrophages into the lesion sites. In addition, RBCs and Hb increased several nucleotide-binding oligomerization domain-like receptors' expression and induced IL-1β release. Our results provide novel insights into the protumor function of RBCs and Hb as endogenous danger signals, which can promote tumor cell proliferation, macrophage recruitment, and polarization. Hemorrhage may represent a useful prognostic factor for cancer patients because of its role in tumor promotion and chemoresistance. Copyright © 2014 by The American Association of Immunologists, Inc.

Competitive Outcomes and Endogenous Coalition Formation in an n-Person Game

NARCIS (Netherlands)

Sun, N.; Trockel, W.; Yang, Z.F.

2004-01-01

In this paper we study competitive outcomes and endogenous coalition formation in a cooperative n-person transferable utility (TU) game from the viewpoint of general equilibrium theory.For any given game, we construct a competitive exchange coalition production economy corresponding to the game.

L-carnitine is an endogenous HDAC inhibitor selectively inhibiting cancer cell growth in vivo and in vitro.

Science.gov (United States)

Huang, Hongbiao; Liu, Ningning; Guo, Haiping; Liao, Siyan; Li, Xiaofen; Yang, Changshan; Liu, Shouting; Song, Wenbin; Liu, Chunjiao; Guan, Lixia; Li, Bing; Xu, Li; Zhang, Change; Wang, Xuejun; Dou, Q Ping; Liu, Jinbao

2012-01-01

L-carnitine (LC) is generally believed to transport long-chain acyl groups from fatty acids into the mitochondrial matrix for ATP generation via the citric acid cycle. Based on Warburg's theory that most cancer cells mainly depend on glycolysis for ATP generation, we hypothesize that, LC treatment would lead to disturbance of cellular metabolism and cytotoxicity in cancer cells. In this study, Human hepatoma HepG2, SMMC-7721 cell lines, primary cultured thymocytes and mice bearing HepG2 tumor were used. ATP content was detected by HPLC assay. Cell cycle, cell death and cell viability were assayed by flow cytometry and MTS respectively. Gene, mRNA expression and protein level were detected by gene microarray, Real-time PCR and Western blot respectively. HDAC activities and histone acetylation were detected both in test tube and in cultured cells. A molecular docking study was carried out with CDOCKER protocol of Discovery Studio 2.0 to predict the molecular interaction between L-carnitine and HDAC. Here we found that (1) LC treatment selectively inhibited cancer cell growth in vivo and in vitro; (2) LC treatment selectively induces the expression of p21(cip1) gene, mRNA and protein in cancer cells but not p27(kip1); (4) LC increases histone acetylation and induces accumulation of acetylated histones both in normal thymocytes and cancer cells; (5) LC directly inhibits HDAC I/II activities via binding to the active sites of HDAC and induces histone acetylation and lysine-acetylation accumulation in vitro; (6) LC treatment induces accumulation of acetylated histones in chromatin associated with the p21(cip1) gene but not p27(kip1) detected by ChIP assay. These data support that LC, besides transporting acyl group, works as an endogenous HDAC inhibitor in the cell, which would be of physiological and pathological importance.

Endogenous lycopene improves ethanol production under acetic acid stress in Saccharomyces cerevisiae.

Science.gov (United States)

Pan, Shuo; Jia, Bin; Liu, Hong; Wang, Zhen; Chai, Meng-Zhe; Ding, Ming-Zhu; Zhou, Xiao; Li, Xia; Li, Chun; Li, Bing-Zhi; Yuan, Ying-Jin

2018-01-01

Acetic acid, generated from the pretreatment of lignocellulosic biomass, is a significant obstacle for lignocellulosic ethanol production. Reactive oxidative species (ROS)-mediated cell damage is one of important issues caused by acetic acid. It has been reported that decreasing ROS level can improve the acetic acid tolerance of Saccharomyces cerevisiae . Lycopene is known as an antioxidant. In the study, we investigated effects of endogenous lycopene on cell growth and ethanol production of S. cerevisiae in acetic acid media. By accumulating endogenous lycopene during the aerobic fermentation of the seed stage, the intracellular ROS level of strain decreased to 1.4% of that of the control strain during ethanol fermentation. In the ethanol fermentation system containing 100 g/L glucose and 5.5 g/L acetic acid, the lag phase of strain was 24 h shorter than that of control strain. Glucose consumption rate and ethanol titer of yPS002 got to 2.08 g/L/h and 44.25 g/L, respectively, which were 2.6- and 1.3-fold of the control strain. Transcriptional changes of INO1 gene and CTT1 gene confirmed that endogenous lycopene can decrease oxidative stress and improve intracellular environment. Biosynthesis of endogenous lycopene is first associated with enhancing tolerance to acetic acid in S. cerevisiae . We demonstrate that endogenous lycopene can decrease intracellular ROS level caused by acetic acid, thus increasing cell growth and ethanol production. This work innovatively   puts forward a new strategy for second generation bioethanol production during lignocellulosic fermentation.

From Experiment to Theory: What Can We Learn from Growth Curves?

Science.gov (United States)

Kareva, Irina; Karev, Georgy

2018-01-01

Finding an appropriate functional form to describe population growth based on key properties of a described system allows making justified predictions about future population development. This information can be of vital importance in all areas of research, ranging from cell growth to global demography. Here, we use this connection between theory and observation to pose the following question: what can we infer about intrinsic properties of a population (i.e., degree of heterogeneity, or dependence on external resources) based on which growth function best fits its growth dynamics? We investigate several nonstandard classes of multi-phase growth curves that capture different stages of population growth; these models include hyperbolic-exponential, exponential-linear, exponential-linear-saturation growth patterns. The constructed models account explicitly for the process of natural selection within inhomogeneous populations. Based on the underlying hypotheses for each of the models, we identify whether the population that it best fits by a particular curve is more likely to be homogeneous or heterogeneous, grow in a density-dependent or frequency-dependent manner, and whether it depends on external resources during any or all stages of its development. We apply these predictions to cancer cell growth and demographic data obtained from the literature. Our theory, if confirmed, can provide an additional biomarker and a predictive tool to complement experimental research.

SOME IMPLICATIONS OF A CONCEPT OF GROWTH MOTIVATION FOR ADULT EDUCATION THEORY AND PRACTICE.

Science.gov (United States)

NOREEN, DAVID SHELDON

THIS STUDY EXAMINED GROWTH MOTIVATION AS A DEVELOPING CONCEPT AND AS A THEORETICAL CONSTRUCT, AND THE IMPLICATIONS OF THIS THEORY FOR ADULT EDUCATION THEORY AND PRACTICE. SPECIAL ATTENTION WAS GIVEN TO THE THEORETICAL CONSTRUCTS OF ABRAHAM MASLOW, TO THE NATURE OF GROWTH MOTIVATION CONCEPTS IN GENERAL, AND TO FORMS OF SELF UNDERSTANDING AND…

Further comparisons of endogenous pyrogens and leukocytic endogenous mediators.

Science.gov (United States)

Kampschmidt, R F; Upchurch, H F; Worthington, M L

1983-07-01

It was recently shown (Murphy et al., Infect. Immun. 34:177-183), that rabbit macrophages produce two biochemically and immunologically distinct endogenous pyrogens. One of these has or copurifies with substances having a molecular weight of 13,000 and a pI of 7.3. This protein was produced by blood monocytes or inflammatory cells elicited in 16-h rabbit peritoneal exudates. These acute peritoneal exudates were produced by the intraperitoneal injection of large volumes of saline containing shellfish glycogen. When the leukocytes in these exudates were washed and incubated at 37 degrees C in saline, they released an endogenous pyrogen. The injection of this pyrogen into rabbits, rats, or mice caused the biological manifestations which have been attributed to leukocytic endogenous mediator. These effects were increases in blood neutrophils, the lowering of plasma iron and zinc levels, and the increased synthesis of the acute-phase proteins. The other rabbit endogenous pyrogen seems to be a family of proteins with isoelectric points between 4.5 and 5.0. These proteins are produced by macrophages in the lung, liver, or in chronic peritoneal exudates. In these experiments, the lower-isoelectric-point endogenous pyrogens were produced by macrophages from the peritoneal cavity of rabbits that had been injected 4 days earlier with 50 ml of light mineral oil. These rabbit pyrogens were found to have leukocytic endogenous mediator activity in mice but to be completely inactive in rats. When injected into rabbits, these proteins produced fever, lowered plasma iron, increased blood neutrophils, but failed to elevate plasma fibrinogen.

Clinical study of the hypothesis of “endogenous collateral wind” on ...

African Journals Online (AJOL)

This study was to propose the hypothesis of “endogenous collateral wind” based on the patho-mechanism of thrombogenesis complicated by ruptured plaque on ACS, and the theory of traditional Chinese medicine. Materials and Methods: Through successful coronary angiography (CAG), and intravascular ultrasound ...

The Implications of Psychosocial Theory for Personal Growth in the Family.

Science.gov (United States)

Newman, Philip R.; Newman, Barbara M.

Psychosocial theory, based on the ideas of Erik Erikson and Robert Havighurst, is proposed as a useful framework for conceptualizing the potential for growth within the family. Erikson's (1950) eight stage theory of psychosocial development and Havighurst's (1959) concept of developmental tasks are used to take account of the stages of development…

The birth and growth of quantum theory. From quantum hypothesis to quantum mechanics

International Nuclear Information System (INIS)

Peng Huanwu

2001-01-01

The short history covers the birth and early growth of quantum theory from 1900 to 1928, beginning with Planck's formula and the quantum hypothesis for the black-body radiation. After a description of the rise and decline of the old quantum theory in connection with its application in spectroscopy, two paths based on the rigorous formulation of the correspondence principle leading to matrix mechanics (1925) and Dirac's non-commuting q-numbers (1925) are explained. Another path based on the generalization of the wave-particle aspect of light quanta is then shown to lead to wave mechanics (1926). Among the works during the early growth of quantum mechanics in 1927-1928, representation theory, the uncertainty principle, two-electron problems, and Dirac's relativistic theory of electrons are discussed

Lack of endogenous parathyroid hormone delays fracture healing by inhibiting vascular endothelial growth factor‑mediated angiogenesis.

Science.gov (United States)

Ding, Qingfeng; Sun, Peng; Zhou, Hao; Wan, Bowen; Yin, Jian; Huang, Yao; Li, Qingqing; Yin, Guoyong; Fan, Jin

2018-07-01

Intermittent low‑dose injections of parathyroid hormone (PTH) have been reported to exert bone anabolic effects and to promote fracture healing. As an important proangiogenic cytokine, vascular endothelial growth factor (VEGF) is secreted by bone marrow mesenchymal stem cells (BMSCs) and osteoblasts, and serves a crucial regulatory role in the process of vascular development and regeneration. To investigate whether lack of endogenous PTH causes reduced angiogenic capacity and thereby delays the process of fracture healing by downregulating the VEGF signaling pathway, a PTH knockout (PTHKO) mouse fracture model was generated. Fracture healing was observed using X‑ray and micro‑computerized tomography. Bone anabolic and angiogenic markers were analyzed by immunohistochemistry and western blot analysis. The expression levels of VEGF and associated signaling pathways in murine BMSC‑derived osteoblasts were measured by quantitative polymerase chain reaction and western blot analysis. The expression levels of protein kinase A (PKA), phosphorylated‑serine/threonine protein kinase (pAKT), hypoxia‑inducible factor‑1α (HIF1α) and VEGF were significantly decreased in BMSC‑derived osteoblasts from PTHKO mice. In addition, positive platelet endothelial cell adhesion molecule staining was reduced in PTHKO mice, as determined by immunohistochemistry. The expression levels of HIF1α, VEGF, runt‑related transcription factor 2, osteocalcin and alkaline phosphatase were also decreased in PTHKO mice, and fracture healing was delayed. In conclusion, lack of endogenous PTH may reduce VEGF expression in BMSC‑derived osteoblasts by downregulating the activity of the PKA/pAKT/HIF1α/VEGF pathway, thus affecting endochondral bone formation by causing a reduction in angiogenesis and osteogenesis, ultimately leading to delayed fracture healing.

Exogenic and endogenic Europa minerals

Science.gov (United States)

Maynard-Casely, H. E.; Brand, H. E. A.; Wilson, S. A.

2016-12-01

The Galileo Near Infrared Mapping Spectrometer (NIMS) identified a significant `non-ice' component upon the surface of Jupiter's moon Europa. Current explanations invoke both endogenic and exogenic origins for this material. It has long been suggested that magnesium and sodium sulfate minerals could have leached from the rock below a putative ocean (endogenic) 1 and that sulfuric acid hydrate minerals could have been radiologically produced from ionised sulfur originally from Io's volcanoes (exogenic) 2. However, a more recent theory proposes that the `non-ice' component could be radiation damaged NaCl leached from Europa's speculative ocean 3. What if the minerals are actually from combination of both endogenic and exogenic sources? To investigate this possibility we have focused on discovering new minerals that might form in the combination of the latter two cases, that is a mixture of leached sulfates hydrates with radiologically produced sulfuric acid. To this end we have explored a number of solutions in the MgSO4-H2SO4-H2O and Na2SO4-H2SO4-H2O systems, between 80 and 280 K with synchrotron x-ray powder diffraction. We report a number of new materials formed in this these ternary systems. This suggests that it should be considered that the `non-ice' component of the Europa's surface could be a material derived from endogenic and exogenic components. 1 Kargel, J. S. Brine volcanism and the interior structures of asteroids and icy satellites. Icarus 94, 368-390 (1991). 2 Carlson, R. W., Anderson, M. S., Mehlman, R. & Johnson, R. E. Distribution of hydrate on Europa: Further evidence for sulfuric acid hydrate. Icarus 177, 461-471, doi:10.1016/j.icarus.2005.03.026 (2005). 3 Hand, K. P. & Carlson, R. W. Europa's surface color suggests an ocean rich with sodium chloride. Geophysical Research Letters, 2015GL063559, doi:10.1002/2015gl063559 (2015).

Study on Applicability of Conceptual Hydrological Models for Flood Forecasting in Humid, Semi-Humid Semi-Arid and Arid Basins in China

Directory of Open Access Journals (Sweden)

Guangyuan Kan

2017-09-01

Full Text Available Flood simulation and forecasting in various types of watersheds is a hot issue in hydrology. Conceptual hydrological models have been widely applied to flood forecasting for decades. With the development of economy, modern China faces with severe flood disasters in all types of watersheds include humid, semi-humid semi-arid and arid watersheds. However, conceptual model-based flood forecasting in semi-humid semi-arid and arid regions is still challenging. To investigate the applicability of conceptual hydrological models for flood forecasting in the above mentioned regions, three typical conceptual models, include Xinanjiang (XAJ, mix runoff generation (MIX and northern Shannxi (NS, are applied to 3 humid, 3 semi-humid semi-arid, and 3 arid watersheds. The rainfall-runoff data of the 9 watersheds are analyzed based on statistical analysis and information theory, and the model performances are compared and analyzed based on boxplots and scatter plots. It is observed the complexity of drier watershed data is higher than that of the wetter watersheds. This indicates the flood forecasting is harder in drier watersheds. Simulation results indicate all models perform satisfactorily in humid watersheds and only NS model is applicable in arid watersheds. Model with consideration of saturation excess runoff generation (XAJ and MIX perform better than the infiltration excess-based NS model in semi-humid semi-arid watersheds. It is concluded more accurate mix runoff generation theory, more stable and efficient numerical solution of infiltration equation and rainfall data with higher spatial-temporal resolution are main obstacles for conceptual model-based flood simulation and forecasting.

Intergenerational redistribution in a small open economy with endogenous fertility.

Science.gov (United States)

Kolmar, M

1997-08-01

The literature comparing fully funded (FF) and pay-as-you-go (PAYG) financed public pension systems in small, open economies stresses the importance of the Aaron condition as an empirical measure to decide which system can be expected to lead to a higher long-run welfare. A country with a PAYG system has a higher level of utility than a country with a FF system if the growth rate of total wage income exceeds the interest rate. Endogenizing population growth makes one determinant of the growth rate of wage incomes endogenous. The author demonstrates why the Aaron condition ceases to be a good indicator in this case. For PAYG-financed pension systems, claims can be calculated according to individual contributions or the number of children in a family. Analysis determined that for both structural determinants there is no interior solution of the problem of intergenerational utility maximization. Pure systems are therefore always welfare maximizing. Moreover, children-related pension claims induce a fiscal externality which tends to be positive. The determination of the optimal contribution rate shows that the Aaron condition is generally a misleading indicator for the comparison of FF and PAYG-financed pension systems.

Corruption and economic growth with non constant labor force growth

Science.gov (United States)

Brianzoni, Serena; Campisi, Giovanni; Russo, Alberto

2018-05-01

Based on Brianzoni et al. [1] in the present work we propose an economic model regarding the relationship between corruption in public procurement and economic growth. We extend the benchmark model by introducing endogenous labor force growth, described by the logistic equation. The results of previous studies, as Del Monte and Papagni [2] and Mauro [3], show that countries are stuck in one of the two equilibria (high corruption and low economic growth or low corruption and high economic growth). Brianzoni et al. [1] prove the existence of a further steady state characterized by intermediate levels of capital per capita and corruption. Our aim is to investigate the effects of the endogenous growth around such equilibrium. Moreover, due to the high number of parameters of the model, specific attention is given to the numerical simulations which highlight new policy measures that can be adopted by the government to fight corruption.

Does tax competition really promote growth?

DEFF Research Database (Denmark)

Köthenbürger, Marko; Lockwood, Ben

2010-01-01

This paper considers the relationship between tax competition and growth in an endogenous growth model where there are stochastic shocks to productivity, and capital taxes fund a public good which may be for final consumption or an infrastructure input. Absent stochastic shocks, decentralized tax...... the centralized level. Growth can be lower with decentralization. Our results also predict a negative relationship between output volatility and growth with decentralization.......This paper considers the relationship between tax competition and growth in an endogenous growth model where there are stochastic shocks to productivity, and capital taxes fund a public good which may be for final consumption or an infrastructure input. Absent stochastic shocks, decentralized tax...

Is growth bad for the environment? Pollution, abatement and endogenous growth

NARCIS (Netherlands)

J.G.M. van Marrewijk (Charles); F. van der Ploeg (Ploeg); J.B.L.M. Verbeek (Jos)

1993-01-01

textabstractRecentiy, the importance of environmental and economic "win-win" situations has been stressed, indicating that care of the environment requires economic growth, while economic growth in turn cannot take place without taking proper care of the environment. We generalize a popular

The endogeneity of money and the eurosystem

OpenAIRE

Steiger, Otto

2004-01-01

The endogenous theory of money, developed by Basil Moore, argues that the supply of central bank money in modern economies is not under the control of the central bank. According to this view, a central bank typically supplies cash reserves automatically on demand at its minimum lending rate, resulting in a clearly horizontal money supply function. While the paper agrees with Moore that the supply of central bank money cannot be determined exogenously by the central bank, it wonders whether t...

Eye growth and myopia development: Unifying theory and Matlab model.

Science.gov (United States)

Hung, George K; Mahadas, Kausalendra; Mohammad, Faisal

2016-03-01

The aim of this article is to present an updated unifying theory of the mechanisms underlying eye growth and myopia development. A series of model simulation programs were developed to illustrate the mechanism of eye growth regulation and myopia development. Two fundamental processes are presumed to govern the relationship between physiological optics and eye growth: genetically pre-programmed signaling and blur feedback. Cornea/lens is considered to have only a genetically pre-programmed component, whereas eye growth is considered to have both a genetically pre-programmed and a blur feedback component. Moreover, based on the Incremental Retinal-Defocus Theory (IRDT), the rate of change of blur size provides the direction for blur-driven regulation. The various factors affecting eye growth are shown in 5 simulations: (1 - unregulated eye growth): blur feedback is rendered ineffective, as in the case of form deprivation, so there is only genetically pre-programmed eye growth, generally resulting in myopia; (2 - regulated eye growth): blur feedback regulation demonstrates the emmetropization process, with abnormally excessive or reduced eye growth leading to myopia and hyperopia, respectively; (3 - repeated near-far viewing): simulation of large-to-small change in blur size as seen in the accommodative stimulus/response function, and via IRDT as well as nearwork-induced transient myopia (NITM), leading to the development of myopia; (4 - neurochemical bulk flow and diffusion): release of dopamine from the inner plexiform layer of the retina, and the subsequent diffusion and relay of neurochemical cascade show that a decrease in dopamine results in a reduction of proteoglycan synthesis rate, which leads to myopia; (5 - Simulink model): model of genetically pre-programmed signaling and blur feedback components that allows for different input functions to simulate experimental manipulations that result in hyperopia, emmetropia, and myopia. These model simulation programs

Institutions, Technological Change and Economic Growth

Directory of Open Access Journals (Sweden)

David Corderí Novoa

2005-01-01

Full Text Available Theories of economic growth try to explain variations in per capita income across countries by differences in capital accumulation and productivity. However, many scholars consider that integrating institutions into economic theory and economic history is an essential step in improving explanations of why some societies are richer than others. This paper develops the empirical and theoretical case that differences in institutions are the fundamental cause of differences in technological change (productivity, hence in economic growth. First, I give a definition of institutions and how they influence economic performance, from a New Institutional Economics point of view. Then, I introduce the theoretical framework based on the economics of ideas and endogenous growth models. Finally, I argue that R&D expenditures -a proxy for technological change- will vary across countries depending on some measures of institutional quality. In the end, this paper finds that stronger institutions (measured by an aggregate of institutional quality encourage greater R&D expenditures. At a disaggregate level, the rule of law is positively correlated and the regulatory burden is negatively correlated with R&D expenditures. Human capital level (measured by the tertiary and primary school enrolment rates has also a significant positive impact in R&D expenditures.

Endogenous Lunar Volatiles

Science.gov (United States)

McCubbin, F. M.; Liu, Y.; Barnes, J. J.; Anand, M.; Boyce, J. W.; Burney, D.; Day, J. M. D.; Elardo, S. M.; Hui, H.; Klima, R. L.; Magna, T.; Ni, P.; Steenstra, E.; Tartèse, R.; Vander Kaaden, K. E.

2018-04-01

This abstract discusses numerous outstanding questions on the topic of endogenous lunar volatiles that will need to be addressed in the coming years. Although substantial insights into endogenous lunar volatiles have been gained, more work remains.

Cancer Theory from Systems Biology Point of View

Science.gov (United States)

Wang, Gaowei; Tang, Ying; Yuan, Ruoshi; Ao, Ping

In our previous work, we have proposed a novel cancer theory, endogenous network theory, to understand mechanism underlying cancer genesis and development. Recently, we apply this theory to hepatocellular carcinoma (HCC). A core endogenous network of hepatocyte was established by integrating the current understanding of hepatocyte at molecular level. Quantitative description of the endogenous network consisted of a set of stochastic differential equations which could generate many local attractors with obvious or non-obvious biological functions. By comparing with clinical observation and experimental data, the results showed that two robust attractors from the model reproduced the main known features of normal hepatocyte and cancerous hepatocyte respectively at both modular and molecular level. In light of our theory, the genesis and progression of cancer is viewed as transition from normal attractor to HCC attractor. A set of new insights on understanding cancer genesis and progression, and on strategies for cancer prevention, cure, and care were provided.

Endogenous neurogenesis in the human brain following cerebral infarction.

Science.gov (United States)

Minger, Stephen L; Ekonomou, Antigoni; Carta, Eloisa M; Chinoy, Amish; Perry, Robert H; Ballard, Clive G

2007-01-01

Increased endogenous neurogenesis has a significant regenerative role in many experimental models of cerebrovascular diseases, but there have been very few studies in humans. We therefore examined whether there was evidence of altered endogenous neurogenesis in an 84-year-old patient who suffered a cerebrovascular accident 1 week prior to death. Using antibodies that specifically label neural stem/neural progenitor cells, we examined the presence of immunopositive cells around and distant from the infarcted area, and compared this with a control, age-matched individual. Interestingly, a large number of neural stem cells, vascular endothelial growth factor-immunopositive cells and new blood vessels were observed only around the region of infarction, and none in the corresponding brain areas of the healthy control. In addition, an increased number of neural stem cells was observed in the neurogenic region of the lateral ventricle wall. Our results suggest increased endogenous neurogenesis associated with neovascularization and migration of newly-formed cells towards a region of cerebrovascular damage in the adult human brain and highlight possible mechanisms underlying this process.

A re-examination of the biphasic theory of skeletal muscle growth.

Science.gov (United States)

Levine, A S; Hegarty, P V

1977-01-01

Because of the importance of fibre diameter measurements it was decided to re-evaluate the biphasic theory of skeletal muscle growth and development. This theory proposes an initial memophasic distribution of muscle fibres which changes to a biphasic distribution during development. The theory is based on observations made on certain muscles in mice, where two distinct populations of fibre diameters (20 and 40 micronm) contribute to the biphasic distribution. In the present investigation corss sections of frozen biceps brachii of mice in rigor mortis were examined. The rigor state was used to avoid complications produced by thaw-rigor contraction. The diameters of the outermost and innermost fibres were found to be significantly different. However, if the outer and inner fibres were combined to form one group, no significant difference between this group and other random groups was found. The distributions of all groups were monophasic. The diameters of isolated fibres from mice and rats also displayed a monophasic distribution. This evidence leads to the conclusion that the biphasic theory of muscle growth is untenable. Some of the variables which may occur in fibre size and shape are discussed. Images Fig. 1 PMID:858691

The Dynamic Relationship between Crime and Economic Growth in Nigeria

Directory of Open Access Journals (Sweden)

Adekoya Adenuga Fabian

2017-03-01

Full Text Available Crime is a major impediment to economic growth and development in Nigeria despite measures taken to reduce it. There is, however, currently no major statistical analysis of how crime affects economic growth in that country. This study examines the link between crime and growth based on the theory of rational choice and empirical data. Exogenous and endogenous growth models are employed, and include deterrence variables. The period examined is 1970–2013 and estimation is done using the autoregressive distributed lag model. The results of our study show that crime affects economic growth at a 1% and 10% level of significance. In other words, crime imposes the costs of prosecution and punishment on the citizens and country, which influences the growth of the economy. Given our results, we suggest that police and the system of justice should be strengthened. Indeed, this may be necessary if the development target stated in Nigeria vision 20: 2020 is to be reached.

Growth and lipid accumulation characteristics of Scenedesmus obliquus in semi-continuous cultivation outdoors for biodiesel feedstock production.

Science.gov (United States)

Feng, Pingzhong; Yang, Kang; Xu, Zhongbin; Wang, Zhongming; Fan, Lu; Qin, Lei; Zhu, Shunni; Shang, Changhua; Chai, Peng; Yuan, Zhenhong; Hu, Lei

2014-12-01

In an effort to identify suitable microalgal species for biodiesel production, seven species were isolated from various habitats and their growth characteristics were compared. The results demonstrated that a green alga Scenedesmus obliquus could grow more rapidly and synthesize more lipids than other six microalgal strains. S. obliquus grew well both indoors and outdoors, and reached higher μmax indoors than that outdoors. However, the cells achieved higher dry weight (4.36 g L(-1)), lipid content (49.6%) and productivity (183 mg L(-1) day(-1)) outdoors than in indoor cultures. During the 61 days semi-continuous cultivation outdoors, high biomass productivities (450-550 mg L(-1) day(-1)) and μmax (1.05-1.44 day(-1)) were obtained. The cells could also achieve high lipid productivities (151-193 mg L(-1) day(-1)). These results indicated that S. obliquus was promising for lipids production in semi-continuous cultivation outdoors. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cinnamaldehyde promotes root branching by regulating endogenous hydrogen sulfide.

Science.gov (United States)

Xue, Yan-Feng; Zhang, Meng; Qi, Zhong-Qiang; Li, You-Qin; Shi, Zhiqi; Chen, Jian

2016-02-01

Cinnamaldehyde (CA) has been widely applied in medicine and food preservation. However, whether and how CA regulates plant physiology is largely unknown. To address these gaps, the present study investigated the beneficial effect of CA on root branching and its possible biochemical mechanism. The lateral root (LR) formation of pepper seedlings could be markedly induced by CA at specific concentrations without any inhibitory effect on primary root (PR) growth. CA could induce the generation of endogenous hydrogen sulfide (H2S) by increasing the activity of L-cysteine desulfhydrase in roots. By fluorescently tracking endogenous H2S in situ, it could be clearly observed that H2S accumulated in the outer layer cells of the PR where LRs emerge. Sodium hydrosulfide (H2S donor) treatment induced LR formation, while hypotaurine (H2S scavenger) showed an adverse effect. The addition of hypotaurine mitigated the CA-induced increase in endogenous H2S level, which in turn counteracted the inducible effect of CA on LR formation. CA showed great potential in promoting LR formation, which was mediated by endogenous H2S. These results not only shed new light on the application of CA in agriculture but also extend the knowledge of H2S signaling in the regulation of root branching. © 2015 Society of Chemical Industry.

Tax Evasion in a Model of Endogenous Growth

OpenAIRE

Been-Lon Chen

2003-01-01

This paper integrates tax evasion into a standard AK growth model with public capital. In the model, the government optimizes the tax rate, while individuals optimize tax evasion. It studies tax rate, tax evasion and economic growth, and compares them with otherwise identical economies except those without tax evasion. It inquires into the effects of three government policies on tax rate, tax evasion, and economic growth. It finds that an increase in both unit cost of tax evasion and punishme...

Optimal Patent Life in a Variety-Expansion Growth Model

OpenAIRE

Lin, Hwan C.

2013-01-01

This paper presents more channels through which the optimal patent life is determined in a R&D-based endogenous growth model that permits growth of new varieties of consumer goods over time. Its modeling features include an endogenous hazard rate facing incumbent monopolists, the prevalence of research congestion, and the aggregate welfare importance of product differentiation. As a result, a patent’s effective life is endogenized and less than its legal life. The model is calibrated to a glo...

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.

The Endogenous Exposome

Science.gov (United States)

Nakamura, Jun; Mutlu, Esra; Sharma, Vyom; Collins, Leonard; Bodnar, Wanda; Yu, Rui; Lai, Yongquan; Moeller, Benjamin; Lu, Kun; Swenberg, James

2014-01-01

The concept of the Exposome, is a compilation of diseases and one’s lifetime exposure to chemicals, whether the exposure comes from environmental, dietary, or occupational exposures; or endogenous chemicals that are formed from normal metabolism, inflammation, oxidative stress, lipid peroxidation, infections, and other natural metabolic processes such as alteration of the gut microbiome. In this review, we have focused on the Endogenous Exposome, the DNA damage that arises from the production of endogenous electrophilic molecules in our cells. It provides quantitative data on endogenous DNA damage and its relationship to mutagenesis, with emphasis on when exogenous chemical exposures that produce identical DNA adducts to those arising from normal metabolism cause significant increases in total identical DNA adducts. We have utilized stable isotope labeled chemical exposures of animals and cells, so that accurate relationships between endogenous and exogenous exposures can be determined. Advances in mass spectrometry have vastly increased both the sensitivity and accuracy of such studies. Furthermore, we have clear evidence of which sources of exposure drive low dose biology that results in mutations and disease. These data provide much needed information to impact quantitative risk assessments, in the hope of moving towards the use of science, rather than default assumptions. PMID:24767943

Production of endogenous pyrogen.

Science.gov (United States)

Dinarello, C A

1979-01-01

The production and release of endogenous pyrogen by the host is the first step in the pathogenesis of fever. Endogenous pyrogen is a low-molecular-weight protein released from phagocytic leukocytes in response to several substances of diverse nature. Some of these agents stimulate production of endogenous pyrogen because they are toxic; others act as antigens and interact with either antibody or sensitized lymphocytes in order to induce its production. Some tumors of macrophage origin produce the molecule spontaneously. Whatever the mechanism involved, endogenous pyrogen is synthesized following transcription of new DNA and translation of mRNA into new protein. Once synthesis is completed, the molecule is released without significant intracellular storage. Recent evidence suggests that following release, molecular aggregates form which are biologically active. In its monomer form, endogenous pyrogen is a potent fever-producing substance and mediates fever by its action on the thermoregulatory center.

On the non-causal link between volatility and growth

DEFF Research Database (Denmark)

Posch, Olaf; Wälde, Klaus

A model highlighting the endogeneity of both volatility and growth is presented. Volatility and growth are therefore correlated but there is no causal link from volatility to growth. This joint endogeneity is illustrated by working out the effects through which economies with different tax levels...... di er both in their volatility and growth. Using a continuous-time DSGE model with plausible parametric restrictions, we obtain closedform measures of macro volatility based on cyclical components and output growth rates. Given our results, empirical volatility-growth analysis should include controls...

To Save or to Consume: Linking Growth Theory with the Keynesian Model

Science.gov (United States)

Kwok, Yun-kwong

2007-01-01

In the neoclassical growth theory, higher saving rate gives rise to higher output per capita. However, in the Keynesian model, higher saving rate causes lower consumption, which may lead to a recession. Students may ask, "Should we save or should we consume?" In most of the macroeconomics textbooks, economic growth and Keynesian economics are in…

Adult stem cell theory of the multi-stage, multi-mechanism theory of carcinogenesis: role of inflammation on the promotion of initiated stem cells.

Science.gov (United States)

Trosko, James E; Tai, Mei-Hui

2006-01-01

Inflammation, induced by microbial agents, radiation, endogenous or exogenous chemicals, has been associated with chronic diseases, including cancer. Since carcinogenesis has been characterized as consisting of the 'initiation', 'promotion' and 'progression' phases, the inflammatory process could affect any or all three phases. The stem cell theory of carcinogenesis has been given a revival, in that isolated human adult stem cells have been isolated and shown to be 'targets' for neoplastic transformation. Oct4, a transcription factor, has been associated with adult stem cells, as well as their immortalized and tumorigenic derivatives, but not with the normal differentiated daughters. These data are consistent with the stem cell theory of carcinogenesis. In addition, Gap Junctional Intercellular Communication (GJIC) seems to play a major role in cell growth. Inhibition of GJIC by non-genotoxic chemicals or various oncogenes seems to be the mechanism for the tumor promotion and progression phases of carcinogenesis. Many of the toxins, synthetic non-genotoxicants, and endogenous inflammatory factors have been shown to inhibit GJIC and act as tumor promoters. The inhibition of GJIC might be the mechanism by which the inflammatory process affects cancer and that to intervene during tumor promotion with anti-inflammatory factors might be the most efficacious anti-cancer strategy.

Growth and Functionality of Cells Cultured on Conducting and Semi-Conducting Surfaces Modified with Self-Assembled Monolayers (SAMs

Directory of Open Access Journals (Sweden)

Rajendra K. Aithal

2016-02-01

Full Text Available Bioengineering of dermal and epidermal cells on surface modified substrates is an active area of research. The cytotoxicity, maintenance of cell phenotype and long-term functionality of human dermal fibroblast (HDF cells on conducting indium tin oxide (ITO and semi-conducting, silicon (Si and gallium arsenide (GaAs, surfaces modified with self-assembled monolayers (SAMs containing amino (–NH2 and methyl (–CH3 end groups have been investigated. Contact angle measurements and infrared spectroscopic studies show that the monolayers are conformal and preserve their functional end groups. Morphological analyses indicate that HDFs grow well on all substrates except GaAs, exhibiting their normal spindle-shaped morphology and exhibit no visible signs of stress or cytoplasmic vacuolation. Cell viability analyses indicate little cell death after one week in culture on all substrates except GaAs, where cells died within 6 h. Cells on all surfaces proliferate except on GaAs and GaAs-ODT. Cell growth is observed to be greater on SAM modified ITO and Si-substrates. Preservation of cellular phenotype assessed through type I collagen immunostaining and positive staining of HDF cells were observed on all modified surfaces except that on GaAs. These results suggest that conducting and semi-conducting SAM-modified surfaces support HDF growth and functionality and represent a promising area of bioengineering research.

A REVIEW OF FINANCE–GROWTH NEXUS THEORIES: HOW DOES DEVELOPMENT FINANCE FITS IN?

OpenAIRE

MARWA Nyankomo; ZHANJE Stephen

2015-01-01

The finance growth-nexus debates have been contentious over the past three decades both empirically and theoretically. To contribute to this debate, the current paper presents a concise review of finance-growths nexus theoretical development and the current debate around growth-finance nexus theories. Then, it extends the current theoretical debate to include development finance within the broader scheme of finance-growth discourse. The key emerging trend is that, most of the contemporary the...

Generalized bi-quasi-variational inequalities for quasi-semi-monotone and bi-quasi-semi-monotone operators with applications in non-compact settings and minimization problems

Directory of Open Access Journals (Sweden)

Chowdhury Molhammad SR

2000-01-01

Full Text Available Results are obtained on existence theorems of generalized bi-quasi-variational inequalities for quasi-semi-monotone and bi-quasi-semi-monotone operators in both compact and non-compact settings. We shall use the concept of escaping sequences introduced by Border (Fixed Point Theorem with Applications to Economics and Game Theory, Cambridge University Press, Cambridge, 1985 to obtain results in non-compact settings. Existence theorems on non-compact generalized bi-complementarity problems for quasi-semi-monotone and bi-quasi-semi-monotone operators are also obtained. Moreover, as applications of some results of this paper on generalized bi-quasi-variational inequalities, we shall obtain existence of solutions for some kind of minimization problems with quasi- semi-monotone and bi-quasi-semi-monotone operators.

Aspergillus terreus endogenous endophthalmitis: Report of a case and review of literature

Directory of Open Access Journals (Sweden)

Pradeep Kumar Panigrahi

2014-01-01

Full Text Available We report a rare case of Aspergillus terreus endogenous endophthalmitis in an immunocompetent patient with subretinal abscess and also review the reported cases. A 50-year-old healthy male presented with sudden painful loss of vision in right eye. He was diagnosed with endogenous endophthalmitis and underwent urgent vitrectomy. Aspergillus terreus growth was obtained in culture. At final follow-up, there was complete resolution of the infection but visual acuity was poor due to macular scar. Aspergillus terreus is a rare cause of endophthalmitis with usually poor outcomes. Newer antifungals like Voriconazole can be sometimes associated with better prognosis.

Poverty-led higher population growth in Bangladesh.

Science.gov (United States)

Nakibullah, A; Rahman, A

1996-01-01

This article discusses the issue whether population growth is exogenous or endogenous in the economic development of Bangladesh. Overpopulation adversely affects food supplies, foreign exchange, and human resources. Moreover, it depresses savings per capita and retards growth of physical capital per labor. Underdeveloped countries, like Bangladesh, are faced with the problem of allocating resources between infrastructure, education, and health service that are essential for human capital development and population control measures. With this, determination whether fertility is exogenous or endogenous is important for policy purposes in the context of Bangladesh. Results showed that there is a correlation between population growth and real gross domestic products per capita. Based on Granger causality test, population growth is endogenous in the development process of Bangladesh and its overpopulation is due to poverty. Thus, there is a need for appropriate policy to take measures to improve human capital and decrease fertility rates.

Selection theory of free dendritic growth in a potential flow.

Science.gov (United States)

von Kurnatowski, Martin; Grillenbeck, Thomas; Kassner, Klaus

2013-04-01

The Kruskal-Segur approach to selection theory in diffusion-limited or Laplacian growth is extended via combination with the Zauderer decomposition scheme. This way nonlinear bulk equations become tractable. To demonstrate the method, we apply it to two-dimensional crystal growth in a potential flow. We omit the simplifying approximations used in a preliminary calculation for the same system [Fischaleck, Kassner, Europhys. Lett. 81, 54004 (2008)], thus exhibiting the capability of the method to extend mathematical rigor to more complex problems than hitherto accessible.

Endogenous Locus Reporter Assays.

Science.gov (United States)

Liu, Yaping; Hermes, Jeffrey; Li, Jing; Tudor, Matthew

2018-01-01

Reporter gene assays are widely used in high-throughput screening (HTS) to identify compounds that modulate gene expression. Traditionally a reporter gene assay is built by cloning an endogenous promoter sequence or synthetic response elements in the regulatory region of a reporter gene to monitor transcriptional activity of a specific biological process (exogenous reporter assay). In contrast, an endogenous locus reporter has a reporter gene inserted in the endogenous gene locus that allows the reporter gene to be expressed under the control of the same regulatory elements as the endogenous gene, thus more accurately reflecting the changes seen in the regulation of the actual gene. In this chapter, we introduce some of the considerations behind building a reporter gene assay for high-throughput compound screening and describe the methods we have utilized to establish 1536-well format endogenous locus reporter and exogenous reporter assays for the screening of compounds that modulate Myc pathway activity.

Oscillations in a Growth Model with Capital, Technology and Environment with Exogenous Shocks

Directory of Open Access Journals (Sweden)

Wei-Bin Zhang

2015-07-01

Full Text Available This paper generalizes the dynamic growth model with wealth accumulation, technological change and environmental change by Zhang (2012 by making all the parameters as time-dependent parameters. The model treats physical capital accumulation, knowledge creation and utilization, and environmental change as endogenous variables. It synthesizes the basic ideas of the neoclassical growth theory, Arrow’s learning-by-doing model and the traditional dynamic models of environmental change within a comprehensive framework. The behavior of the household is described with an alternative approach to household behavior. We simulated the model to demonstrate existence of equilibrium points, motion of the dynamic system, and oscillations due to different exogenous shocks.

Endogenous technological and demographic change under increasing water scarcity

Science.gov (United States)

Pande, Saket; Ertsen, Maurits; Sivapalan, Murugesu

2014-05-01

The ancient civilization in the Indus Valley civilization dispersed under extreme dry conditions; there are indications that the same holds for many other ancient societies. Even contemporary societies, such as the one in Murrumbidgee river basin in Australia, have started to witness a decline in overall population under increasing water scarcity. Hydroclimatic change may not be the sole predictor of the fate of contemporary societies in water scarce regions and many critics of such (perceived) hydroclimatic determinism have suggested that technological change may ameliorate the effects of increasing water scarcity and as such counter the effects of hydroclimatic changes. To study the role of technological change on the dynamics of coupled human-water systems, we develop a simple overlapping-generations model of endogenous technological and demographic change. We model technological change as an endogenous process that depends on factors such as the investments that are (endogenously) made in a society, the (endogenous) diversification of a society into skilled and unskilled workers, a society's patience in terms of its present consumption vs. future consumption, production technology and the (endogenous) interaction of all of these factors. In the model the population growth rate is programmed to decline once consumption per capita crosses a "survival" threshold. This means we do not treat technology as an exogenous random sequence of events, but instead assume that it results (endogenously) from societal actions. The model demonstrates that technological change may indeed ameliorate the effects of increasing water scarcity but typically it does so only to a certain extent. It is possible that technological change may allow a society to escape the effect of increasing water scarcity, leading to a (super)-exponential rise in technology and population. However, such cases require the rate of success of investment in technological advancement to be high. In other

Endogenous technological and population change under increasing water scarcity

Science.gov (United States)

Pande, S.; Ertsen, M.; Sivapalan, M.

2013-11-01

The ancient civilization in the Indus Valley civilization dispersed under extreme dry conditions; there are indications that the same holds for many other ancient societies. Even contemporary societies, such as the one in Murrumbidgee river basin in Australia, have started to witness a decline in overall population under increasing water scarcity. Hydroclimatic change may not be the sole predictor of the fate of contemporary societies in water scarce regions and many critics of such (perceived) hydroclimatic determinism have suggested that technological change may ameliorate the effects of increasing water scarcity and as such counter the effects of hydroclimatic changes. To study the role of technological change on the dynamics of coupled human-water systems, we develop a simple overlapping-generations model of endogenous technological and demographic change. We model technological change as an endogenous process that depends on factors such as the investments that are (endogenously) made in a society, the (endogenous) diversification of a society into skilled and unskilled workers, a society's patience in terms of its present consumption vs. future consumption, production technology and the (endogenous) interaction of all of these factors. In the model the population growth rate is programmed to decline once consumption per capita crosses a "survival" threshold. This means we do not treat technology as an exogenous random sequence of events, but instead assume that it results (endogenously) from societal actions. The model demonstrates that technological change may indeed ameliorate the effects of increasing water scarcity but typically it does so only to a certain extent. It is possible that technological change may allow a society to escape the effect of increasing water scarcity, leading to a (super)-exponential rise in technology and population. However, such cases require the rate of success of investment in technological advancement to be high. In other

A new approach to the semi-classical relativistic two-body problem for charged fermions

International Nuclear Information System (INIS)

Leiter, D.

1978-01-01

Generalizing from a recently developed hybrid formulation of classical electrodynamics with ''direct (charge-field) action'' structure an analogous semi-classical Dirac formulation of the theory is constructed, which is capable of describing the semi-classical quantum mechanics of two identical spin-1/2 particles. This semi-classical formulation is to be used as a heuristic aid in searching for the theoretical structure of a fully ''second quantized'' theory. The Pauli exclusion principle is incorporated by making the interaction fields (in the action principle) antisymmetric with respect to ''charge-field'' labeling. In this manner, ''position correlation'' effects associated with ''configuration interaction'' can also be accounted for. By studying the nature of the stationary-state solutions, the formalism is compared with the conventional quantum-mechanical one (to understand the similarities and the differences between this approach and the usual correlated Hartree-Fock approximation of ordinary relativistic quantum theory). The stationary-state solutions to the semi-classical formalism are shown to closely approximate the usual quantum-mechanical solutions when the wave functions are represented as a superposition of Slater determinants of Dirac-Coulombic-type wave functions with radial parts having a form which extremizes the total Breit energy. The manner in which this semi-classical theory might be extended to a fully ''second quantized'' formalism is sketched. (author)

A Family of Integrable Rational Semi-Discrete Systems and Its Reduction

International Nuclear Information System (INIS)

Xu Xixiang

2010-01-01

Within framework of zero curvature representation theory, a family of integrahle rational semi-discrete systems is derived from a matrix spectral problem. The Hamiltonian forms of obtained semi-discrete systems are constructed by means of the discrete trace identity. The Liouville integrability for the obtained family is demonstrated. In the end, a reduced family of obtained semi-discrete systems and its Hamiltonian form are worked out. (general)

Maintenance, endogeneous, respiration, lysis, decay and predation

DEFF Research Database (Denmark)

loosdrecht, Marc C. M. Van; Henze, Mogens

1999-01-01

mechanism is microbiologically correct. The lysis/decay model mechanism is a strongly simplified representation of reality. This paper tries to review the processes grouped under endogenous respiration in activated sludge models. Mechanisms and processes such as maintenance, lysis, internal and external...... decay, predation and death-regeneration are discussed. From recent microbial research it has become evident that cells do not die by themselves. Bacteria are however subject to predation by protozoa. Bacteria store reserve polymers that in absence of external substrate are used for growth...

Ponderal development and growth traits of Anglonubian goats raised under semi-intensive system Desenvolvimento ponderal e características de crescimento de caprinos da raça Anglonubiana criados em sistema semi-intensivo

Directory of Open Access Journals (Sweden)

Milton Rezende Teixeira Neto

2009-06-01

Full Text Available The goal of this study was to characterize, by mathematic models, the growth pattern of Anglonubian goats raised under semi-intensive system. Data from 43 males and 33 females were used to estimate the growth of animals based on non-linear models. The effects from sex, birth month and birth type on living weight and on average daily weight gain (DWG at different ages were analyzed. The logistic model has proved to be the most adequate one to estimate the growth curves of males and females. The birth type influenced the living weight up to 60 days of age (P<0.05 and the birth month presented no effects. The sex affected the GPD until 150 days of age and affected the living weight at all ages, with males heavier than females (P<0.05. The DWG was higher at younger ages, being equal to 194 ± 42 g from birth to 30 days and 91 ± 60 g from 210 to 240 days, with about 150 g/day from birth to 150 days of age. Anglonubian goats raised under semi-intensive system show satisfactory performance for meat production and the logistic model is adequate to estimate the growth pattern of the kids from this breed.Objetivou-se avaliar o padrão de crescimento de caprinos da raça Anglonubiana criados sob sistema semi-intensivo. Os dados oriundos de 43 machos e 33 fêmeas foram utilizados para estimar o crescimento dos animais com base em modelos não-lineares, tendo sido analisados os efeitos de sexo, mês e tipo de nascimento, sobre o peso vivo e o ganho de peso diário (GPD em diferentes idades. O modelo Logístico mostrou-se o mais adequado para estimar a curva de crescimento de machos e fêmeas. O tipo de nascimento influenciou o peso vivo até os 60 dias (P<0,05, enquanto que o mês de nascimento não apresentou efeito significativo. O sexo afetou o GPD até 150 dias de idade assim como afetou o peso vivo em todas as idades, sendo os machos mais pesados que as fêmeas (P<0,05. O GPD foi maior em idades mais jovens, sendo igual a 194 ± 42 g do nascimento aos

Interdependence of cell growth and gene expression: origins and consequences.

Science.gov (United States)

Scott, Matthew; Gunderson, Carl W; Mateescu, Eduard M; Zhang, Zhongge; Hwa, Terence

2010-11-19

In bacteria, the rate of cell proliferation and the level of gene expression are intimately intertwined. Elucidating these relations is important both for understanding the physiological functions of endogenous genetic circuits and for designing robust synthetic systems. We describe a phenomenological study that reveals intrinsic constraints governing the allocation of resources toward protein synthesis and other aspects of cell growth. A theory incorporating these constraints can accurately predict how cell proliferation and gene expression affect one another, quantitatively accounting for the effect of translation-inhibiting antibiotics on gene expression and the effect of gratuitous protein expression on cell growth. The use of such empirical relations, analogous to phenomenological laws, may facilitate our understanding and manipulation of complex biological systems before underlying regulatory circuits are elucidated.

Targeted detection of in vivo endogenous DNA base damage reveals preferential base excision repair in the transcribed strand.

Science.gov (United States)

Reis, António M C; Mills, Wilbur K; Ramachandran, Ilangovan; Friedberg, Errol C; Thompson, David; Queimado, Lurdes

2012-01-01

Endogenous DNA damage is removed mainly via base excision repair (BER), however, whether there is preferential strand repair of endogenous DNA damage is still under intense debate. We developed a highly sensitive primer-anchored DNA damage detection assay (PADDA) to map and quantify in vivo endogenous DNA damage. Using PADDA, we documented significantly higher levels of endogenous damage in Saccharomyces cerevisiae cells in stationary phase than in exponential phase. We also documented that yeast BER-defective cells have significantly higher levels of endogenous DNA damage than isogenic wild-type cells at any phase of growth. PADDA provided detailed fingerprint analysis at the single-nucleotide level, documenting for the first time that persistent endogenous nucleotide damage in CAN1 co-localizes with previously reported spontaneous CAN1 mutations. To quickly and reliably quantify endogenous strand-specific DNA damage in the constitutively expressed CAN1 gene, we used PADDA on a real-time PCR setting. We demonstrate that wild-type cells repair endogenous damage preferentially on the CAN1 transcribed strand. In contrast, yeast BER-defective cells accumulate endogenous damage preferentially on the CAN1 transcribed strand. These data provide the first direct evidence for preferential strand repair of endogenous DNA damage and documents the major role of BER in this process.

Effect of human vascular endothelial growth factor gene transfer on endogenous vascular endothelial growth factor mRNA expression in a rat fibroblast and osteoblast culture model.

Science.gov (United States)

Li, Ru; Li, Claire H; Nauth, Aaron; McKee, Michael D; Schemitsch, Emil H

2010-09-01

Vascular endothelial growth factor (VEGF) plays an important role in promoting angiogenesis and osteogenesis during fracture repair. Our previous studies have shown that cell-based VEGF gene therapy enhances bone healing of a rabbit tibia segmental bone defect in vivo. The aim of this project was to examine the effect of exogenous human VEGF on the endogenous rat VEGF messenger RNA (mRNA) expression in a cell-based gene transfer model. Rat fibroblasts and osteoblasts were harvested from the dermal tissue and periosteum, respectively, of Fisher 344 rats. The cells were then cultured and transfected with pcDNA-human VEGF using Superfect reagent (Qiagen). Four experimental groups were created: 1) fibroblast-VEGF; 2) osteoblast-VEGF; 3) nontransfected fibroblast controls; and 4) nontransfected osteoblast controls. The cultured cells were harvested at 1, 3, and 7 days after the gene transfection. The total mRNA was extracted (Trizol; Invitrogen); both human VEGF and rat VEGF mRNA were measured by reverse transcriptase-polymerase chain reaction and quantified by VisionWorksLS. The human VEGF165 mRNA was detected by reverse transcriptase-polymerase chain reaction from transfected fibroblasts and osteoblasts at 1, 3, and 7 days after gene transfection. The human VEGF165 levels peaked at Day 1 and then gradually reduced expression in both transfected fibroblasts and osteoblasts. Two endogenous rat VEGF isoforms were detected in this cell culture model: rat VEGF120 and rat VEGF164. We compared the rat VEGF120 and rat VEGF164 expression level of the fibroblasts or osteoblasts that were transfected with human VEGF165, with nontransfected control cells. Both the transfected fibroblasts and osteoblasts showed greater expression of rat VEGF164 than nontransfected controls at Day 1 (peak level) and Day 3, but not at Day 7. The expression of rat VEGF120 was lower in transfected fibroblasts, but higher in transfected osteoblasts, than the relevant control groups at any time point

Recognition of GPCRs by peptide ligands and membrane compartments theory: structural studies of endogenous peptide hormones in membrane environment.

Science.gov (United States)

Sankararamakrishnan, Ramasubbu

2006-04-01

One of the largest family of cell surface proteins, G-protein coupled receptors (GPCRs) regulate virtually all known physiological processes in mammals. With seven transmembrane segments, they respond to diverse range of extracellular stimuli and represent a major class of drug targets. Peptidergic GPCRs use endogenous peptides as ligands. To understand the mechanism of GPCR activation and rational drug design, knowledge of three-dimensional structure of receptor-ligand complex is important. The endogenous peptide hormones are often short, flexible and completely disordered in aqueous solution. According to "Membrane Compartments Theory", the flexible peptide binds to the membrane in the first step before it recognizes its receptor and the membrane-induced conformation is postulated to bind to the receptor in the second step. Structures of several peptide hormones have been determined in membrane-mimetic medium. In these studies, micelles, reverse micelles and bicelles have been used to mimic the cell membrane environment. Recently, conformations of two peptide hormones have also been studied in receptor-bound form. Membrane environment induces stable secondary structures in flexible peptide ligands and membrane-induced peptide structures have been correlated with their bioactivity. Results of site-directed mutagenesis, spectroscopy and other experimental studies along with the conformations determined in membrane medium have been used to interpret the role of individual residues in the peptide ligand. Structural differences of membrane-bound peptides that belong to the same family but differ in selectivity are likely to explain the mechanism of receptor selectivity and specificity of the ligands. Knowledge of peptide 3D structures in membrane environment has potential applications in rational drug design.

Endogenous Technology Adoption and Medical Costs.

Science.gov (United States)

Lamiraud, Karine; Lhuillery, Stephane

2016-09-01

Despite the claim that technology has been one of the most important drivers of healthcare spending growth over the past decades, technology variables are rarely introduced explicitly in cost equations. Furthermore, technology is often considered exogenous. Using 1996-2007 panel data on Swiss geographical areas, we assessed the impact of technology availability on per capita healthcare spending covered by basic health insurance whilst controlling for the endogeneity of health technology availability variables. Our results suggest that medical research, patent intensity and the density of employees working in the medical device industry are influential factors for the adoption of technology and can be used as instruments for technology availability variables in the cost equation. These results are similar to previous findings: CT and PET scanner adoption is associated with increased healthcare spending, whilst increased availability of percutaneous transluminal coronary angioplasty facilities is associated with reductions in per capita spending. However, our results suggest that the magnitude of these relationships is much greater in absolute value than that suggested by previous studies that did not control for the possible endogeneity of the availability of technologies. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

2D problems of surface growth theory with applications to additive manufacturing

Science.gov (United States)

Manzhirov, A. V.; Mikhin, M. N.

2018-04-01

We study 2D problems of surface growth theory of deformable solids and their applications to the analysis of the stress-strain state of AM fabricated products and structures. Statements of the problems are given, and a solution method based on the approaches of the theory of functions of a complex variable is suggested. Computations are carried out for model problems. Qualitative and quantitative results are discussed.

Expression of endogenous proteins in maize hybrids in a multi-location field trial in India.

Science.gov (United States)

Gutha, Linga R; Purushottam, Divakar; Veeramachaneni, Aruna; Tigulla, Sarita; Kodappully, Vikas; Enjala, Chandana; Rajput, Hitendrasinh; Anderson, Jennifer; Hong, Bonnie; Schmidt, Jean; Bagga, Shveta

2018-05-17

Genetically modified (GM) crops undergo large scale multi-location field trials to characterize agronomics, composition, and the concentration of newly expressed protein(s) [herein referred to as transgenic protein(s)]. The concentration of transgenic proteins in different plant tissues and across the developmental stages of the plant is considered in the safety assessment of GM crops. Reference or housekeeping proteins are expected to maintain a relatively stable expression pattern in healthy plants given their role in cellular functions. Understanding the effects of genotype, growth stage and location on the concentration of endogenous housekeeping proteins may provide insight into the contribution these factors could have on transgenic protein concentrations in GM crops. The concentrations of three endogenous proteins (actin, elongation factor 1-alpha, and glyceraldehyde 3-phosphate dehydrogenase) were measured in several different maize hybrids grown across multiple field locations over 2 years. Leaf samples were collected from healthy plants at three developmental stages across the growing seasons, and protein concentrations were quantified by indirect enzyme-linked immunosorbent assay (ELISA) for each protein. In general, the concentrations of these three endogenous proteins were relatively consistent across hybrid backgrounds, when compared within one growth stage and location (2-26%CV), whereas the concentrations of proteins in the same hybrid and growth stage across different locations were more variable (12-64%CV). In general, the protein concentrations in 2013 and 2014 show similar trends in variability. Some degree of variability in protein concentrations should be expected for both transgenic and endogenous plant-expressed proteins. In the case of GM crops, the potential variation in protein concentrations due to location effects is captured in the current model of multi-location field testing.

Controlled cross-over study in normal subjects of naloxone-preceding-lactate infusions; respiratory and subjective responses: relationship to endogenous opioid system, suffocation false alarm theory and childhood parental loss.

Science.gov (United States)

Preter, M; Lee, S H; Petkova, E; Vannucci, M; Kim, S; Klein, D F

2011-02-01

The expanded suffocation false alarm theory (SFA) hypothesizes that dysfunction in endogenous opioidergic regulation increases sensitivity to CO2, separation distress and panic attacks. In panic disorder (PD) patients, both spontaneous clinical panics and lactate-induced panics markedly increase tidal volume (TV), whereas normals have a lesser effect, possibly due to their intact endogenous opioid system. We hypothesized that impairing the opioidergic system by naloxone could make normal controls parallel PD patients' response when lactate challenged. Whether actual separations and losses during childhood (childhood parental loss, CPL) affected naloxone-induced respiratory contrasts was explored. Subjective panic-like symptoms were analyzed although pilot work indicated that the subjective aspect of anxious panic was not well modeled by this specific protocol. Randomized cross-over sequences of intravenous naloxone (2 mg/kg) followed by lactate (10 mg/kg), or saline followed by lactate, were given to 25 volunteers. Respiratory physiology was objectively recorded by the LifeShirt. Subjective symptomatology was also recorded. Impairment of the endogenous opioid system by naloxone accentuates TV and symptomatic response to lactate. This interaction is substantially lessened by CPL. Opioidergic dysregulation may underlie respiratory pathophysiology and suffocation sensitivity in PD. Comparing specific anti-panic medications with ineffective anti-panic agents (e.g. propranolol) can test the specificity of the naloxone+lactate model. A screen for putative anti-panic agents and a new pharmacotherapeutic approach are suggested. Heuristically, the experimental unveiling of the endogenous opioid system impairing effects of CPL and separation in normal adults opens a new experimental, investigatory area.

Controlled cross-over study in normal subjects of naloxone-preceding-lactate infusions; respiratory and subjective responses: relationship to endogenous opioid system, suffocation false alarm theory and childhood parental loss

Science.gov (United States)

Preter, M.; Lee, S. H.; Petkova, E.; Vannucci, M.; Kim, S.; Klein, D. F.

2015-01-01

Background The expanded suffocation false alarm theory (SFA) hypothesizes that dysfunction in endogenous opioidergic regulation increases sensitivity to CO2, separation distress and panic attacks. In panic disorder (PD) patients, both spontaneous clinical panics and lactate-induced panics markedly increase tidal volume (TV), whereas normals have a lesser effect, possibly due to their intact endogenous opioid system. We hypothesized that impairing the opioidergic system by naloxone could make normal controls parallel PD patients' response when lactate challenged. Whether actual separations and losses during childhood (childhood parental loss, CPL) affected naloxone-induced respiratory contrasts was explored. Subjective panic-like symptoms were analyzed although pilot work indicated that the subjective aspect of anxious panic was not well modeled by this specific protocol. Method Randomized cross-over sequences of intravenous naloxone (2 mg/kg) followed by lactate (10 mg/kg), or saline followed by lactate, were given to 25 volunteers. Respiratory physiology was objectively recorded by the LifeShirt. Subjective symptomatology was also recorded. Results Impairment of the endogenous opioid system by naloxone accentuates TV and symptomatic response to lactate. This interaction is substantially lessened by CPL. Conclusions Opioidergic dysregulation may underlie respiratory pathophysiology and suffocation sensitivity in PD. Comparing specific anti-panic medications with ineffective anti-panic agents (e.g. propranolol) can test the specificity of the naloxone + lactate model. A screen for putative anti-panic agents and a new pharmacotherapeutic approach are suggested. Heuristically, the experimental unveiling of the endogenous opioid system impairing effects of CPL and separation in normal adults opens a new experimental, investigatory area. PMID:20444308

Microscopic theory of nuclear collective dynamics

International Nuclear Information System (INIS)

Sakata, Fumihiko; Marumori, Toshio; Hashimoto, Yukio; Tsukuma, Hidehiko; Yamamoto, Yoshifumi; Iwasawa, Kazuo.

1990-10-01

A recent development of the INS-TSUKUBA joint research project on large-amplitude collective motion is summarized by putting special emphasis on an inter-relationship between quantum chaos and nuclear spectroscopy. Aiming at introducing various concepts used in this lecture, we start with recapitulating the semi-classical theory of nuclear collective dynamics formulated within the time-dependent Hartree-Fock (TDHF) theory. The central part of the semi-classical theory is provided by the self-consistent collective coordinate (SCC) method which has been developed to properly take account of the non-linear dynamics specific for the finite many-body quantum system. A decisive role of the level crossing dynamics on the order-to-chaos transition of collective motion is discussed in detail. Extending the basic idea of the semi-classical theory, we discuss a full quantum theory of nuclear collective dynamics which allows us to properly define a concept of the quantum integrability as well as the quantum chaoticity for each eigenfunction. The lecture is arranged so as to clearly show the similar structure between the semi-classical and quantum theories of nuclear collective dynamics. Using numerical calculations, we illustrate what the quantum chaos for each eigenfunction means and relate it to the usual definition of quantum chaos for nearest neighbor level spacing statistics based on the random matrix theory. (author)

Application of Semi-analytical Satellite Theory orbit propagator to orbit determination for space object catalog maintenance

Science.gov (United States)

Setty, Srinivas J.; Cefola, Paul J.; Montenbruck, Oliver; Fiedler, Hauke

2016-05-01

Catalog maintenance for Space Situational Awareness (SSA) demands an accurate and computationally lean orbit propagation and orbit determination technique to cope with the ever increasing number of observed space objects. As an alternative to established numerical and analytical methods, we investigate the accuracy and computational load of the Draper Semi-analytical Satellite Theory (DSST). The standalone version of the DSST was enhanced with additional perturbation models to improve its recovery of short periodic motion. The accuracy of DSST is, for the first time, compared to a numerical propagator with fidelity force models for a comprehensive grid of low, medium, and high altitude orbits with varying eccentricity and different inclinations. Furthermore, the run-time of both propagators is compared as a function of propagation arc, output step size and gravity field order to assess its performance for a full range of relevant use cases. For use in orbit determination, a robust performance of DSST is demonstrated even in the case of sparse observations, which is most sensitive to mismodeled short periodic perturbations. Overall, DSST is shown to exhibit adequate accuracy at favorable computational speed for the full set of orbits that need to be considered in space surveillance. Along with the inherent benefits of a semi-analytical orbit representation, DSST provides an attractive alternative to the more common numerical orbit propagation techniques.

Entrepreneurship, Information, and Growth

Science.gov (United States)

Bunten, Devin; Weiler, Stephan; Weiler, Stephan; Zahran, Sammy

2016-01-01

We examine the contribution to economic growth of entrepreneurial “marketplace information” within a regional endogenous growth framework. Entrepreneurs are posited to provide an input to economic growth through the information revealed by their successes and failures. We empirically identify this information source with the regional variation in establishment births and deaths, which create geographic information asymmetries that influence subsequent entrepreneurial activity and economic growth. We find that local establishment birth and death rates are significantly and positively correlated with subsequent entrepreneurship for US counties. To account for the potential endogeneity caused by forward-looking entrepreneurs, we utilize instruments based on historic mining activity. We find that the information spillover component of local establishment birth and death rates have significant positive effects on subsequent entrepreneurship and employment growth for US counties and metropolitan areas. With the help of these intruments, we show that establishment births have a positive and significant effect on future employment growth within all counties, and that in line with the information hypothesis, local establishment death rates have a similar positive effect within metropolitan counties. PMID:27516625

Cultural theory revised: Only five cultures or more?

NARCIS (Netherlands)

van Heffen, O.; Klok, Pieter J.

2003-01-01

This article deals with cultural theory in the version of Thompson, Ellis and Wildavsky. Cultural theory is important for research in the area of political and policy science because this theory has the pretension of pinning down endogenous preference formation. Using Durkheim's dimensions, 'social

On the origins of endogenous thoughts.

Science.gov (United States)

Tillas, Alexandros

2017-05-01

Endogenous thoughts are thoughts that we activate in a top-down manner or in the absence of the appropriate stimuli. We use endogenous thoughts to plan or recall past events. In this sense, endogenous thinking is one of the hallmarks of our cognitive lives. In this paper, I investigate how it is that we come to possess endogenous control over our thoughts. Starting from the close relation between language and thinking, I look into speech production-a process motorically controlled by the inferior frontal gyrus (IFG). Interestingly, IFG is also closely related to silent talking, as well as volition. The connection between IFG and volition is important given that endogenous thoughts are or at least greatly resemble voluntary actions. Against this background, I argue that IFG is key to understanding the origins of conscious endogenous thoughts. Furthermore, I look into goal-directed thinking and show that IFG plays a key role also in unconscious endogenous thinking.

Tree Morphologic Plasticity Explains Deviation from Metabolic Scaling Theory in Semi-Arid Conifer Forests, Southwestern USA.

Directory of Open Access Journals (Sweden)

Tyson L Swetnam

Full Text Available A significant concern about Metabolic Scaling Theory (MST in real forests relates to consistent differences between the values of power law scaling exponents of tree primary size measures used to estimate mass and those predicted by MST. Here we consider why observed scaling exponents for diameter and height relationships deviate from MST predictions across three semi-arid conifer forests in relation to: (1 tree condition and physical form, (2 the level of inter-tree competition (e.g. open vs closed stand structure, (3 increasing tree age, and (4 differences in site productivity. Scaling exponent values derived from non-linear least-squares regression for trees in excellent condition (n = 381 were above the MST prediction at the 95% confidence level, while the exponent for trees in good condition were no different than MST (n = 926. Trees that were in fair or poor condition, characterized as diseased, leaning, or sparsely crowned had exponent values below MST predictions (n = 2,058, as did recently dead standing trees (n = 375. Exponent value of the mean-tree model that disregarded tree condition (n = 3,740 was consistent with other studies that reject MST scaling. Ostensibly, as stand density and competition increase trees exhibited greater morphological plasticity whereby the majority had characteristically fair or poor growth forms. Fitting by least-squares regression biases the mean-tree model scaling exponent toward values that are below MST idealized predictions. For 368 trees from Arizona with known establishment dates, increasing age had no significant impact on expected scaling. We further suggest height to diameter ratios below MST relate to vertical truncation caused by limitation in plant water availability. Even with environmentally imposed height limitation, proportionality between height and diameter scaling exponents were consistent with the predictions of MST.

Tree Morphologic Plasticity Explains Deviation from Metabolic Scaling Theory in Semi-Arid Conifer Forests, Southwestern USA.

Science.gov (United States)

Swetnam, Tyson L; O'Connor, Christopher D; Lynch, Ann M

2016-01-01

A significant concern about Metabolic Scaling Theory (MST) in real forests relates to consistent differences between the values of power law scaling exponents of tree primary size measures used to estimate mass and those predicted by MST. Here we consider why observed scaling exponents for diameter and height relationships deviate from MST predictions across three semi-arid conifer forests in relation to: (1) tree condition and physical form, (2) the level of inter-tree competition (e.g. open vs closed stand structure), (3) increasing tree age, and (4) differences in site productivity. Scaling exponent values derived from non-linear least-squares regression for trees in excellent condition (n = 381) were above the MST prediction at the 95% confidence level, while the exponent for trees in good condition were no different than MST (n = 926). Trees that were in fair or poor condition, characterized as diseased, leaning, or sparsely crowned had exponent values below MST predictions (n = 2,058), as did recently dead standing trees (n = 375). Exponent value of the mean-tree model that disregarded tree condition (n = 3,740) was consistent with other studies that reject MST scaling. Ostensibly, as stand density and competition increase trees exhibited greater morphological plasticity whereby the majority had characteristically fair or poor growth forms. Fitting by least-squares regression biases the mean-tree model scaling exponent toward values that are below MST idealized predictions. For 368 trees from Arizona with known establishment dates, increasing age had no significant impact on expected scaling. We further suggest height to diameter ratios below MST relate to vertical truncation caused by limitation in plant water availability. Even with environmentally imposed height limitation, proportionality between height and diameter scaling exponents were consistent with the predictions of MST.

Pathways to Resilience in Semi-Arid Economies | CRDI - Centre de ...

International Development Research Centre (IDRC) Digital Library (Canada)

Pathways to Resilience in Semi-Arid Economies. How can populations become resilient to climate change while pursuing economic growth? This question is at the heart of a research project designed to support climate-resilient economic development in semi-arid lands. It will do so by addressing the conditions for ...

Keynes's theories of money and banking in the Treatise and The General Theory

OpenAIRE

John Smithin

2013-01-01

This paper identifies what seem to have been the five main issues in contention in monetary theory, both historically and in the current era, and discusses the view that J.M. Keynes took on each of them in the Treatise on Money and The General Theory. The key issues in monetary theory are the ontology of money, endogenous versus exogenous money, interest-rate determination, the choice of the monetary policy instrument, and the neutrality versus non-neutrality of money.

The impact of endogenous tax treaties on foreign direct investment: theory and evidence

OpenAIRE

Peter Egger; Mario Larch; Michael Pfaffermayr; Hannes Winner

2006-01-01

This paper investigates the effect of tax treaties on bilateral stocks of outward FDI. For this purpose we employ a numerically solvable general equilibrium model of trade and multinational firms to study the impact of tax treaties on both welfare and outward FDI. The model indicates under which factor endowment configurations countries gain in welfare when implementing a tax treaty. This motivates an empirical specification of the endogenous selection into implementing new tax treaties. Usin...

Endogenous WNT Signals Mediate BMP-Induced and Spontaneous Differentiation of Epiblast Stem Cells and Human Embryonic Stem Cells

Directory of Open Access Journals (Sweden)

Dorota Kurek

2015-01-01

Full Text Available Therapeutic application of human embryonic stem cells (hESCs requires precise control over their differentiation. However, spontaneous differentiation is prevalent, and growth factors induce multiple cell types; e.g., the mesoderm inducer BMP4 generates both mesoderm and trophoblast. Here we identify endogenous WNT signals as BMP targets that are required and sufficient for mesoderm induction, while trophoblast induction is WNT independent, enabling the exclusive differentiation toward either lineage. Furthermore, endogenous WNT signals induce loss of pluripotency in hESCs and their murine counterparts, epiblast stem cells (EpiSCs. WNT inhibition obviates the need to manually remove differentiated cells to maintain cultures and improves the efficiency of directed differentiation. In EpiSCs, WNT inhibition stabilizes a pregastrula epiblast state with novel characteristics, including the ability to contribute to blastocyst chimeras. Our findings show that endogenous WNT signals function as hidden mediators of growth factor-induced differentiation and play critical roles in the self-renewal of hESCs and EpiSCs.

On the seagull effect in semi-inclusive distributions

International Nuclear Information System (INIS)

Ernst, W.

1978-01-01

Taking into account that pions contain two constituents, the semi-inclusive distributions are derived by information theory. From these distributions the psub(L)psub(T) correlations are especially calculated, the results are compared with experimental data

Host-virus interactions of mammalian endogenous retroviruses

OpenAIRE

Farkašová, Helena

2017-01-01

Endogenous retroviruses (ERVs) originate by germline infection and subsequent mendelian inheritance of their exogenous counterparts. With notable exceptions, all mammalian ERVs are evolutionarily old and fixed in the population of its host species. Some groups of retroviruses were believed not to be able to form endogenous copies. We discovered an additional endogenous Lentivirus and a first endogenous Deltaretrovirus. Both of these groups were previously considered unable to form endogenous ...

POSITIVE SOLUTIONS TO SEMI-LINEAR SECOND-ORDER ORDINARY DIFFERENTIAL EQUATIONS IN BANACH SPACE

Institute of Scientific and Technical Information of China (English)

无

2008-01-01

In this paper,we study the existence of positive periodic solution to some second- order semi-linear differential equation in Banach space.By the fixed point index theory, we prove that the semi-linear differential equation has two positive periodic solutions.

Endogenous Monetary Policy Regime Change

OpenAIRE

Troy Davig; Eric M. Leeper

2006-01-01

This paper makes changes in monetary policy rules (or regimes) endogenous. Changes are triggered when certain endogenous variables cross specified thresholds. Rational expectations equilibria are examined in three models of threshold switching to illustrate that (i) expectations formation effects generated by the possibility of regime change can be quantitatively important; (ii) symmetric shocks can have asymmetric effects; (iii) endogenous switching is a natural way to formally model preempt...

Matrix models and stochastic growth in Donaldson-Thomas theory

Energy Technology Data Exchange (ETDEWEB)

Szabo, Richard J. [Department of Mathematics, Heriot-Watt University, Colin Maclaurin Building, Riccarton, Edinburgh EH14 4AS, United Kingdom and Maxwell Institute for Mathematical Sciences, Edinburgh (United Kingdom); Tierz, Miguel [Grupo de Fisica Matematica, Complexo Interdisciplinar da Universidade de Lisboa, Av. Prof. Gama Pinto, 2, PT-1649-003 Lisboa (Portugal); Departamento de Analisis Matematico, Facultad de Ciencias Matematicas, Universidad Complutense de Madrid, Plaza de Ciencias 3, 28040 Madrid (Spain)

2012-10-15

We show that the partition functions which enumerate Donaldson-Thomas invariants of local toric Calabi-Yau threefolds without compact divisors can be expressed in terms of specializations of the Schur measure. We also discuss the relevance of the Hall-Littlewood and Jack measures in the context of BPS state counting and study the partition functions at arbitrary points of the Kaehler moduli space. This rewriting in terms of symmetric functions leads to a unitary one-matrix model representation for Donaldson-Thomas theory. We describe explicitly how this result is related to the unitary matrix model description of Chern-Simons gauge theory. This representation is used to show that the generating functions for Donaldson-Thomas invariants are related to tau-functions of the integrable Toda and Toeplitz lattice hierarchies. The matrix model also leads to an interpretation of Donaldson-Thomas theory in terms of non-intersecting paths in the lock-step model of vicious walkers. We further show that these generating functions can be interpreted as normalization constants of a corner growth/last-passage stochastic model.

Matrix models and stochastic growth in Donaldson-Thomas theory

International Nuclear Information System (INIS)

Szabo, Richard J.; Tierz, Miguel

2012-01-01

We show that the partition functions which enumerate Donaldson-Thomas invariants of local toric Calabi-Yau threefolds without compact divisors can be expressed in terms of specializations of the Schur measure. We also discuss the relevance of the Hall-Littlewood and Jack measures in the context of BPS state counting and study the partition functions at arbitrary points of the Kähler moduli space. This rewriting in terms of symmetric functions leads to a unitary one-matrix model representation for Donaldson-Thomas theory. We describe explicitly how this result is related to the unitary matrix model description of Chern-Simons gauge theory. This representation is used to show that the generating functions for Donaldson-Thomas invariants are related to tau-functions of the integrable Toda and Toeplitz lattice hierarchies. The matrix model also leads to an interpretation of Donaldson-Thomas theory in terms of non-intersecting paths in the lock-step model of vicious walkers. We further show that these generating functions can be interpreted as normalization constants of a corner growth/last-passage stochastic model.

Creative Destruction and Optimal Patent Life in a Variety-Expanding Growth Model

OpenAIRE

Lin, Hwan C.

2013-01-01

This paper presents more channels through which the optimal patent life is determined in a R&D-based endogenous growth model that permits growth of new varieties of consumer goods over time. Its modeling features include an endogenous hazard rate facing incumbent monopolists, the prevalence of research congestion, and the aggregate welfare importance of product differentiation. As a result, a patent’s effective life is endogenized and less than its legal life. The model is calibrated to a glo...

Endogenous MOV10 inhibits the retrotransposition of endogenous retroelements but not the replication of exogenous retroviruses.

Science.gov (United States)

Arjan-Odedra, Shetal; Swanson, Chad M; Sherer, Nathan M; Wolinsky, Steven M; Malim, Michael H

2012-06-22

The identification of cellular factors that regulate the replication of exogenous viruses and endogenous mobile elements provides fundamental understanding of host-pathogen relationships. MOV10 is a superfamily 1 putative RNA helicase that controls the replication of several RNA viruses and whose homologs are necessary for the repression of endogenous mobile elements. Here, we employ both ectopic expression and gene knockdown approaches to analyse the role of human MOV10 in the replication of a panel of exogenous retroviruses and endogenous retroelements. MOV10 overexpression substantially decreased the production of infectious retrovirus particles, as well the propagation of LTR and non-LTR endogenous retroelements. Most significantly, RNAi-mediated silencing of endogenous MOV10 enhanced the replication of both LTR and non-LTR endogenous retroelements, but not the production of infectious retrovirus particles demonstrating that natural levels of MOV10 suppress retrotransposition, but have no impact on infection by exogenous retroviruses. Furthermore, functional studies showed that MOV10 is not necessary for miRNA or siRNA-mediated mRNA silencing. We have identified novel specificity for human MOV10 in the control of retroelement replication and hypothesise that MOV10 may be a component of a cellular pathway or process that selectively regulates the replication of endogenous retroelements in somatic cells.

Mechanisms for catalytic carbon nanofiber growth studied by ab initio density functional theory calculations

DEFF Research Database (Denmark)

Abild-Pedersen, Frank; Nørskov, Jens Kehlet; Rostrup-Nielsen, Jens

2006-01-01

Mechanisms and energetics of graphene growth catalyzed by nickel nanoclusters were studied using ab initio density functional theory calculations. It is demonstrated that nickel step-edge sites act as the preferential growth centers for graphene layers on the nickel surface. Carbon is transported......, and it is argued how these processes may lead to different nanofiber structures. The proposed growth model is found to be in good agreement with previous findings....

A semi-analytical method to estimate the effective slip length of spreading spherical-cap shaped droplets using Cox theory

Science.gov (United States)

Wörner, M.; Cai, X.; Alla, H.; Yue, P.

2018-03-01

The Cox–Voinov law on dynamic spreading relates the difference between the cubic values of the apparent contact angle (θ) and the equilibrium contact angle to the instantaneous contact line speed (U). Comparing spreading results with this hydrodynamic wetting theory requires accurate data of θ and U during the entire process. We consider the case when gravitational forces are negligible, so that the shape of the spreading drop can be closely approximated by a spherical cap. Using geometrical dependencies, we transform the general Cox law in a semi-analytical relation for the temporal evolution of the spreading radius. Evaluating this relation numerically shows that the spreading curve becomes independent from the gas viscosity when the latter is less than about 1% of the drop viscosity. Since inertia may invalidate the made assumptions in the initial stage of spreading, a quantitative criterion for the time when the spherical-cap assumption is reasonable is derived utilizing phase-field simulations on the spreading of partially wetting droplets. The developed theory allows us to compare experimental/computational spreading curves for spherical-cap shaped droplets with Cox theory without the need for instantaneous data of θ and U. Furthermore, the fitting of Cox theory enables us to estimate the effective slip length. This is potentially useful for establishing relationships between slip length and parameters in numerical methods for moving contact lines.

Changes in serum concentrations of growth hormone, insulin, insulin-like growth factor and insulin-like growth factor-binding proteins 1 and 3 and urinary growth hormone excretion during the menstrual cycle

DEFF Research Database (Denmark)

Juul, A; Scheike, Thomas Harder; Pedersen, A T

1997-01-01

Few studies exist on the physiological changes in the concentrations of growth hormone (GH), insulin-like growth factors (IGF) and IGF-binding proteins (IGFBP) within the menstrual cycle, and some controversy remains. We therefore decided to study the impact of endogenous sex steroids on the GH-I...

Features of Cytokine Regulation in Multidrug-Resistant Tuberculosis Depending on Severity of Endogenous Intoxication

Directory of Open Access Journals (Sweden)

L.D. Todoriko

2016-02-01

Conclusions. Comprehensive assessment of integral indices of endogenous intoxication and level of certain pro- and anti-inflammatory cytokines in the blood plasma of patients with MDR TB shows a moderate endogenous intoxication, break down of the cellular component of the immune reactivity due to the formation of conditions for the development of Mycobacterium tuberculosis resistance, with further growth of cytotoxic hypoxia and activation of systemic inflammatory response syndrome. Analysis of plasma concentration of IL-6, IL-10 and IL-18 in patients with multidrug-resistance proved, that their level depends on the nature of Mycobacterium tuberculosis resistance.

Endogenous hallucinogens as ligands of the trace amine receptors: a possible role in sensory perception.

Science.gov (United States)

Wallach, J V

2009-01-01

While the endogenous hallucinogens, N,N-dimethyltryptamine, 5-hydroxy-N,N-dimethyl-tryptamine and 5-methoxy-N,N-dimethyltryptamine, have been acknowledged as naturally occurring components of the mammalian body for decades, their biological function remains as elusive now as it was at the time of their discovery. The recent discovery of the trace amine associated receptors and the activity of DMT and other hallucinogenic compounds at these receptor sites leads to the hypothesis that the endogenous hallucinogens act as neurotransmitters of a subclass of these trace amine receptors. Additionally, while activity at the serotonin 5-HT2A receptor has been proposed as being responsible for the hallucinogenic affects of administered hallucinogens, in their natural setting the 5-HT2A receptor may not interact with the endogenous hallucinogens at all. Additionally 5-HT2A agonist activity is unable to account for the visual altering effects of many of the administered hallucinogens; these effects may be mediated by one of the endogenous hallucinogen trace amine receptors rather than the serotonin 5-HT2A receptor. Therefore, activity at the trace amine receptors, in addition to serotonin receptors, may play a large role in the sensory altering effects of administered hallucinogens and the trace amine receptors along with their endogenous hallucinogen ligands may serve an endogenous role in mediating sensory perception in the mammalian central nervous system. Thus the theory proposed states that these compounds act as true endogenous hallucinogenic transmitters acting in regions of the central nervous system involved in sensory perception.

Influence of magnetic flutter on tearing growth in linear and nonlinear theory

Science.gov (United States)

Kreifels, L.; Hornsby, W. A.; Weikl, A.; Peeters, A. G.

2018-06-01

Recent simulations of tearing modes in turbulent regimes show an unexpected enhancement in the growth rate. In this paper the effect is investigated analytically. The enhancement is linked to the influence of turbulent magnetic flutter, which is modelled by diffusion terms in magnetohydrodynamics (MHD) momentum balance and Ohm’s law. Expressions for the linear growth rate as well as the island width in nonlinear theory for small amplitudes are derived. The results indicate an enhanced linear growth rate and a larger linear layer width compared with resistive MHD. Also the island width in the nonlinear regime grows faster in the diffusive model. These observations correspond well to simulations in which the effect of turbulence on the magnetic island width and tearing mode growth is analyzed.

Homeownership in Slovenia: Searching for an alternative theory on its excessive growth

Directory of Open Access Journals (Sweden)

Richard Sendi

2017-06-01

Full Text Available Recent studies generally show growing levels of homeownership across Europe. However, a comparison of statistical data shows a stark difference in the extent of homeownership between western Europe versus central and eastern Europe. Whereas the development and growth of homeownership in western Europe has been extensively discussed in the literature and various theories have been advanced, its strong dominance in central and eastern Europe has been barely examined. Due to the lack of thorough discourse on this topic, there thus continues to be a void in the literature, which is manifested in the absence of a sound explanation for the comparatively much higher expansion of homeownership in post-communist central and eastern Europe. This article contributes to filling this gap. The central argument is that theories that were developed to explain the growth of homeownership in western Europe (economies with a capitalist tradition might not necessarily apply to situations in central and eastern Europe (with previous communist centrally planned economies. Focusing on the case of Slovenia, the discussion is orientated towards developing an alternative theory that may be more relevant in explaining and understanding the growing preference for homeownership in the country.

ENDOGENEITY OF INDONESIAN MONEY SUPPLY

Directory of Open Access Journals (Sweden)

Meutia Safrina Rachma

2011-09-01

Full Text Available There has been a long debate about the endogeneity of money supply. The main objective of this article is to identify whether money supply in Indonesia is an exogenous or an endogenous variable. Using a Vector Autoregressive model and monthly data 1997(5-2010(6, the estimation result shows that money supply in Indonesia is an endogenous variable. The movement of broad money supply does influence the movement of base money and Consumer Price Index. Consequently, the central bank does not have control power on money supply. The bank is only able to maintain the stability and control the movement of broad money supply. Keywords: Endogenous variable, money supply, vector autoregressionJEL classification numbers: E51, E52, E58

Luxury-based Growth

OpenAIRE

Shiro Kuwahara

2006-01-01

Assuming that there exists a preference for luxury goods and a knowledge spillover from luxury goods production to goods production, this paper constructs an endogenous economic growth model. The model predicts two steady states: one is a steady positive growth state with regard to luxury goods production, and the other is a zero growth state in the absence of luxury goods production. Thus, this study examines the polarization of economies based on luxury goods consumption

Extension of the Johnson-Mehl-Avrami-Kolmogorov theory incorporating anisotropic growth studied by Monte Carlo simulations

NARCIS (Netherlands)

Kooi, BJ

An analytical theory has been developed, based on Monte Carlo (MC) simulations, describing the kinetics of isothermal phase transformations proceeding by nucleation and subsequent growth for d-1 dimensional growth in d dimensional space (with d 2 or 3). This type of growth is of interest since it is

Paclobutrazol biodegradation in unsaturated soil in the Semi-Arid ...

African Journals Online (AJOL)

Paclobutrazol (PBZ) is a plant growth regulator, increasing flowe ring and yield that is widely used in mango cultivation in the semi-arid northeastern Brazil. PBZ remains active in the soil for several years. However, it can severely affect the growth and development of subsequent crops, mainly by reducing vegetative vigor.

Comparison of experiment and theory for elastic-plastic plane strain crack growth

International Nuclear Information System (INIS)

Hermann, L.; Rice, J.R.

1980-02-01

Recent theoretical results on elastic-plastic plane strain crack growth, and experimental results for crack growth in a 4140 steel in terms of the theoretical concepts are reviewed. The theory is based on a recent asymptotic analysis of crack surface opening and strain distributions at a quasi-statically advancing crack tip in an ideally-plastic solid. The analysis is incomplete in that some of the parameters which appear in it are known only approximately, especially at large scale yielding. Nevertheless, it suffices to derive a relation between the imposed loading and amount of crack growth, prior to general yielding, based on the assumption that a geometrically similar near-tip crack profile is maintained during growth. The resulting predictions for the variation of J with crack growth are found to fit well to the experimental results obtained on deeply cracked compact specimens

Endogenous MOV10 inhibits the retrotransposition of endogenous retroelements but not the replication of exogenous retroviruses

Science.gov (United States)

2012-01-01

Background The identification of cellular factors that regulate the replication of exogenous viruses and endogenous mobile elements provides fundamental understanding of host-pathogen relationships. MOV10 is a superfamily 1 putative RNA helicase that controls the replication of several RNA viruses and whose homologs are necessary for the repression of endogenous mobile elements. Here, we employ both ectopic expression and gene knockdown approaches to analyse the role of human MOV10 in the replication of a panel of exogenous retroviruses and endogenous retroelements. Results MOV10 overexpression substantially decreased the production of infectious retrovirus particles, as well the propagation of LTR and non-LTR endogenous retroelements. Most significantly, RNAi-mediated silencing of endogenous MOV10 enhanced the replication of both LTR and non-LTR endogenous retroelements, but not the production of infectious retrovirus particles demonstrating that natural levels of MOV10 suppress retrotransposition, but have no impact on infection by exogenous retroviruses. Furthermore, functional studies showed that MOV10 is not necessary for miRNA or siRNA-mediated mRNA silencing. Conclusions We have identified novel specificity for human MOV10 in the control of retroelement replication and hypothesise that MOV10 may be a component of a cellular pathway or process that selectively regulates the replication of endogenous retroelements in somatic cells. PMID:22727223

Unemployment, Growth and the Organisation of Work

OpenAIRE

Henri L.F. de Groot; Anton B.T.M. van Schaik

2002-01-01

We develop a two-sector endogenous growth model with a dual labour market resulting from the presence of an effort extraction function in one sector. Effort of workers can be influenced by pay and monitoring. This results in an endogenous non-competitive wage differential between sectors and a monitoring intensity that is a source of fixed costs for the firm. Growth is driven by investments in R&D performed in the high-wage sector. Unemployment is determined by the costs and benefits of waiti...

Endogenous Stem Cells Were Recruited by Defocused Low-Energy Shock Wave in Treating Diabetic Bladder Dysfunction.

Science.gov (United States)

Jin, Yang; Xu, Lina; Zhao, Yong; Wang, Muwen; Jin, Xunbo; Zhang, Haiyang

2017-04-01

Defocused low-energy shock wave (DLSW) has been shown effects on activating mesenchymal stromal cells (MSCs) in vitro. In this study, recruitment of endogenous stem cells was firstly examined as an important pathway during the healing process of diabetic bladder dysfunction (DBD) treated by DLSW in vivo. Neonatal rats received intraperitoneal injection of 5-ethynyl-2-deoxyuridine (EdU) and then DBD rat model was created by injecting streptozotocin. Four weeks later, DLSW treatment was performed. Afterward, their tissues were examined by histology. Meanwhile, adipose tissue-derived stem cells (ADSCs) were treated by DLSW in vitro. Results showed DLSW ameliorated voiding function of diabetic rats by recruiting EdU + Stro-1 + CD34 - endogenous stem cells to release abundant nerve growth factor (NGF) and vascular endothelial growth factor (VEGF). Some EdU + cells overlapped with staining of smooth muscle actin. After DLSW treatment, ADSCs showed higher migration ability, higher expression level of stromal cell-derived factor-1 and secreted more NGF and VEGF. In conclusion, DLSW could ameliorate DBD by recruiting endogenous stem cells. Beneficial effects were mediated by secreting NGF and VEGF, resulting into improved innervation and vascularization in bladder.

Schumpeterian growth theory and nuclear R and D

International Nuclear Information System (INIS)

Jeong, H. S.; Yun, S. W.

2001-01-01

The Schumpeterian growth theory with technology innovation and the 4th generation R and D system to build the efficient R and D system are analyzed and some important factors to do practice in the current nuclear R and D are summarized. The factors are asserted to be mentioned in this paper are twofold: first, the necessity of current nuclear R and D system improvement and of national innovation system are described in macroscopic point of view; and second, the necessity of dominant technology and technology diffusion and internal architecturing and forming capability are described in microscopic point of view

Dynamic density functional theory of solid tumor growth: Preliminary models

Directory of Open Access Journals (Sweden)

Arnaud Chauviere

2012-03-01

Full Text Available Cancer is a disease that can be seen as a complex system whose dynamics and growth result from nonlinear processes coupled across wide ranges of spatio-temporal scales. The current mathematical modeling literature addresses issues at various scales but the development of theoretical methodologies capable of bridging gaps across scales needs further study. We present a new theoretical framework based on Dynamic Density Functional Theory (DDFT extended, for the first time, to the dynamics of living tissues by accounting for cell density correlations, different cell types, phenotypes and cell birth/death processes, in order to provide a biophysically consistent description of processes across the scales. We present an application of this approach to tumor growth.

ENDOGENEITY OF INDONESIAN MONEY SUPPLY

OpenAIRE

Rachma, Meutia Safrina

2011-01-01

There has been a long debate about the endogeneity of money supply. The main objective of this article is to identify whether money supply in Indonesia is an exogenous or an endogenous variable. Using a Vector Autoregressive model and monthly data 1997(5)-2010(6), the estimation result shows that money supply in Indonesia is an endogenous variable. The movement of broad money supply does influence the movement of base money and Consumer Price Index. Consequently, the central bank does not hav...

Endogeneity Of Indonesian Money Supply

OpenAIRE

Rachma, Meutia Safrina

2010-01-01

There has been a long debate about the endogeneity of money supply. The main objective of this article is to identify whether money supply in Indonesia is an exogenous or an endogenous variable. Using a Vector Autoregressive model and monthly data 1997(5)-2010(6), the estimation result shows that money supply in Indonesia is an endogenous variable. The movement of broad money supply does influence the movement of base money and Consumer Price Index. Consequently, the central bank does not hav...

MBE growth of Topological Isolators based on strained semi-metallic HgCdTe layers

Science.gov (United States)

Grendysa, J.; Tomaka, G.; Sliz, P.; Becker, C. R.; Trzyna, M.; Wojnarowska-Nowak, R.; Bobko, E.; Sheregii, E. M.

2017-12-01

Particularities of Molecular Beam Epitaxial (MBE) technology for the growth of Topological Insulators (TI) based on the semi-metal Hg1-xCdx Te are presented. A series of strained layers grown on GaAs substrates with a composition close to the 3D Dirac point were studied. The composition of the layers was verified by means of the position of the E1 maximum in optical reflectivity in the visible region. The surface morphology was determined via atomic force and electron microscopy. Magneto-transport measurements show quantized Hall resistance curves and Shubnikov de Hass oscillations (up to 50 K). It has been demonstrated that a well-developed MBE technology enables one to grow strained Hg1-xCdx Te layers on GaAs/CdTe substrates with a well-defined composition near the 3D Dirac point and consequently allows one to produce a 3D topological Dirac semimetal - 3D analogy of graphene - for future applications.

The influence of elevated endogenous free radical production on apoptosis and genomic instability in transgenic growth hormone mice

International Nuclear Information System (INIS)

Lemon, J.A.; Rollo, D.; Boreham, D.R.

2003-01-01

Full text: Previous studies have shown transgenic growth hormone mice (TGM) have significantly elevated levels of endogenous reactive oxygen species (ROS) and lipid peroxidation, shortened lifespan (approximately 50% of normal siblings), greatly enhanced learning in youth, and accelerated aging with a rapid age-related loss of cognitive abilities. A complex oral antioxidant supplement was found to completely abolish the cognitive decline and significantly extend longevity in TGM. We have determined in a recently completed experiment studying radiation-induced apoptosis that the antioxidant supplement significantly reduces the elevated level of apoptosis seen in untreated old TGM compared to age-matched controls. It was also determined that older normal mice treated with the supplement also show a reduction in apoptosis. We are conducting experiments using spectral karyotyping to examine genomic instability in TGM and their normal siblings, that indicate, given their elevated ROS, TGM show an increase in chromosome aberrations compared to normal controls. Based on our previous experiments we speculate that TGM treated with the antioxidant supplement are expected to show a reduction in ROS induced chromosome aberrations

Endogenous Protection Derived from Activin A/Smads Transduction Loop Stimulated via Ischemic Injury in PC12 Cells

OpenAIRE

Mang, Jing; Mei, Chun-Li; Wang, Jiao-Qi; Li, Zong-Shu; Chu, Ting-Ting; He, Jin-Ting; Xu, Zhong-Xin

2013-01-01

Activin A (ActA), a member of transforming growth factor-beta (TGF-b) super- family, affects many cellular processes, including ischemic stroke. Though the neuroprotective effects of exogenous ActA on oxygen-glucose deprivation (OGD) injury have already been reported by us, the endogenous role of ActA remains poorly understood. To further define the role and mechanism of endogenous ActA and its signaling in response to acute ischemic damage, we used an OGD model in PC12 cells to simulate isch...

Optimal Product Variety, Scale Effects and Growth

NARCIS (Netherlands)

de Groot, H.L.F.; Nahuis, R.

1997-01-01

We analyze the social optimality of growth and product variety in a model of endogenous growth. The model contains two sectors, one assembly sector producing a homogenous consumption good, and one intermediate goods sector producing a differentiated input used in the assembly sector. Growth results

Using the electron localization function to correct for confinement physics in semi-local density functional theory

International Nuclear Information System (INIS)

Hao, Feng; Mattsson, Ann E.; Armiento, Rickard

2014-01-01

We have previously proposed that further improved functionals for density functional theory can be constructed based on the Armiento-Mattsson subsystem functional scheme if, in addition to the uniform electron gas and surface models used in the Armiento-Mattsson 2005 functional, a model for the strongly confined electron gas is also added. However, of central importance for this scheme is an index that identifies regions in space where the correction provided by the confined electron gas should be applied. The electron localization function (ELF) is a well-known indicator of strongly localized electrons. We use a model of a confined electron gas based on the harmonic oscillator to show that regions with high ELF directly coincide with regions where common exchange energy functionals have large errors. This suggests that the harmonic oscillator model together with an index based on the ELF provides the crucial ingredients for future improved semi-local functionals. For a practical illustration of how the proposed scheme is intended to work for a physical system we discuss monoclinic cupric oxide, CuO. A thorough discussion of this system leads us to promote the cell geometry of CuO as a useful benchmark for future semi-local functionals. Very high ELF values are found in a shell around the O ions, and take its maximum value along the Cu–O directions. An estimate of the exchange functional error from the effect of electron confinement in these regions suggests a magnitude and sign that could account for the error in cell geometry

Endogenous and exogenously-induced immunomodulation of tumour-host responsiveness

Directory of Open Access Journals (Sweden)

Richard J. Ablin

1987-01-01

Full Text Available In spite of the availability of multiple effector mechanisms of the immune system to combat tumour growth and metastases, their impairment frequently accompanies the appearance of cancer. Factors contributing to this impairment may be related to properties of the host and/or the tumour itself and may be with respect to their origin -endogenous or exogenour. Based on the unique biological behavior of prostate cancer (PCa, and its apparent escape from immune surveillance in the presence of tumour immuno genicity, continuing investigation of endogenous and exogenous factors thought to be relevant to its pathogenesis have been made. For this purpose further studies of the suggested role of human seminal plasma (SePl and the synthetic oestrogen, diethylstiboestrol (DES, as representative endogenous and exogenous immunomodulatory factors (IMF of tumour-host responsiveness, together with evaluation of human prostatic tissue extracts and leuprolide (the luteinizing-hormone-releasing-hormone proposed as an alternate to DES therapy have been made by evaluating their effect on the lytic activity of natural killer (NK cells. SePl and prostate extracts significantly suppressed NK cell lysis. Physicochemical studies suggest SePl and prostate IMF to be associated with high and low molecular weight macromolecules; and implicate the participation of transglutaminase and prostaglandins. Comparative study of therapeutic levels of DES vs. leuprolide on NK cell lysis demonstrated significant suppression by DES vs. a negligible effect of leuprolide. Metastases are highly prevalent in PCa, and contribute significantly to its morbidity and mortality. Further knowledge of the range of effects of endogenous and exogenous IMF on effector mechanisms of tumour-host responsiveness, to include suppression of NK cells, and elucidation of their nature, may contribute toward our understanding of the unique biological behavior of tumours of the prostate, in addition to

Study between the semi-classical and the generator-coordinate methods

International Nuclear Information System (INIS)

Souza Cruz, F.F. de.

1979-01-01

In this work it is performed a comparison between two microscopic theories of the colective movement: semi-classical theory and the quantum theory from the generator -coordinate method. In boths cases, it is used wave packets |p,q> which depend on two canonical conjugate parameters. These wave packets are constructed by the action of displacement unitory operators, which are generated by canonical operators Q-circumflex and P-circumflex on a referencial state. (A.C.A.S.) [pt

Endogenous pyrogen-like substance produced by reptiles.

Science.gov (United States)

Bernheim, H A; Kluger, M J

1977-06-01

1. Injection of lizards (Dipsosaurus dorsalis) with rabbit endogenous pyrogen led to a fever. Injections with denatured endogenous pyrogen did not affect body temperature. 2. Injection of lizards with lizard endogenous pyrogen led to a fever of short duration, while injection of denatured lizard endogenous pyrogen produced no change in body temperature. 3. These data support the hypothesis that the febrile mechanism observed in the higher vertebrates has its origins in some primitive vertebrate.

Capital, population and urban patterns.

Science.gov (United States)

Zhang, W

1994-04-01

The author develops an approach to urban dynamics with endogenous capital and population growth, synthesizing the Alonso location model, the two-sector neoclassical growth model, and endogenous population theory. A dynamic model for an isolated island economy with endogenous capital, population, and residential structure is developed on the basis of Alonso's residential model and the two-sector neoclassical growth model. The model describes the interdependence between residential structure, economic growth, population growth, and economic structure over time and space. It has a unique long-run equilibrium, which may be either stable or unstable, depending upon the population dynamics. Applying the Hopf theorem, the author also shows that when the system is unstable, the economic geography exhibits permanent endogenous oscillations.

Effect of fully and semi austempering treatment on the fatigue properties of ductile cast iron

International Nuclear Information System (INIS)

Kim, Min Gun; Lim, Bok Kyu; Hwang, Jung Gak; Kim, Dong Youl

2005-01-01

Single phase bainite structure which is obtained by the conventional austempering treatment reduces the ductility of ductile cast iron. Because of the reduction of ductility it is possible to worsen the fatigue properties. Therefore, semi austempered ductile iron which is treated from α+γ is prepared to investigate the static strength and fatigue properties in comparison with fully austempered ductile iron (is treated from γ). In spite of semi austempered ductile iron shows the 86% increase of ductility. Also, semi austempered ductile iron shows the higher fatigue limit and lower fatigue crack growth rate as compared with fully austempered ductile iron. By the fractographical analysis, it is revealed that the ferrite obtained by semi austempering process brings about the plastic deformation (ductile striation) of crack tip and gives the prior path of crack propagation. The relatively low crack growth rate in semi austempered specimen is caused by above fractographical reasons

How Do the Richest 1% Owns 50% of Wealth in a Small-Open Growth Model with Endogenous Wealth and Human Capital

Directory of Open Access Journals (Sweden)

Wei-Bin Zhang

2017-01-01

Full Text Available This paper extends the growth model for a closed national economy by Zhang (2015 to a small-open economy. We attempt to explain some economic mechanisms of how the richest one per cent of the population own 50% of national wealth. We consider endogenous wealth and human capital accumulation by heterogeneous households with different preferences and learning abilities as the main determinants of growth and inequality. We describe the production technologies and economic structure on the basis of the Uzawa two-sector model. By applying Zhang’s concept of disposable income and approach to household behavior, we describe consumers’ wealth accumulation and consumption behavior. We model human capital accumulation on the basis of Arrow’s learning by doing and Zhang’s creativity with leisure. We simulate the model with three groups of the population, the rich 1 %, the middle 69%, and the poor 20%. We demonstrate the existence of an equilibrium point at which the rich 1% own more than half of the national wealth and the poor 20% less than 10% of the national wealth. We show how the system moves to the equilibrium from an initial state and confirm that the equilibrium point is stable. We also conduct comparative dynamic analysis.

Effects of extensive system versus semi-intensive and intensive systems on growth and carcass quality of dairy kids

Directory of Open Access Journals (Sweden)

Pedro Zurita Herrera

2011-11-01

Full Text Available The aim of this research was to study the effects of three different management systems on growth and carcass quality of 61 Murciano-Granadina breed kids and their interaction with sex. In the extensive system, 21 kids were allocated to suckle from their dams on free-range pasture with no additional feedstuff. In the semi-intensive system, 20 kids were suckled from their dams and had access to alfalfa hay and cereal straw (no free-range pasture. In the intensive system, 20 kids were separated from the dams at birth and then fed with milk replacer and alfalfa hay. Animals were slaughtered at 7.00 ± 1.00 kg of average BW. The semi-intensive system and extensive system kids grew faster than intensive system animals (127, 113 and 96 g/d, respectively. Differences in energy intake may explain these differences. Intensive system kids displayed the lowest real dressing percentages, calculated as 100 × (hot carcass weight/empty body weight, due to high development of empty gastrointestinal tract. The long leg and carcass were larger in extensive system kids than in kids from other management systems, presumably due to high physical activity on the free-range pastures. The carcasses and cuts from semi-intensive system and extensive system kids displayed more fat than those of intensive system kids. Males grew faster than females (122 and 103 g/d, respectively. Carcasses in male kids showed a higher content of bones but a lower content of fat than carcasses in female kids. The extensive system is feasible for producing kid meat from a dairy breed.

Endogenous sterol biosynthesis is important for mitochondrial function and cell morphology in procyclic forms of Trypanosoma brucei.

Science.gov (United States)

Pérez-Moreno, Guiomar; Sealey-Cardona, Marco; Rodrigues-Poveda, Carlos; Gelb, Michael H; Ruiz-Pérez, Luis Miguel; Castillo-Acosta, Víctor; Urbina, Julio A; González-Pacanowska, Dolores

2012-10-01

Sterol biosynthesis inhibitors are promising entities for the treatment of trypanosomal diseases. Insect forms of Trypanosoma brucei, the causative agent of sleeping sickness, synthesize ergosterol and other 24-alkylated sterols, yet also incorporate cholesterol from the medium. While sterol function has been investigated by pharmacological manipulation of sterol biosynthesis, molecular mechanisms by which endogenous sterols influence cellular processes remain largely unknown in trypanosomes. Here we analyse by RNA interference, the effects of a perturbation of three specific steps of endogenous sterol biosynthesis in order to dissect the role of specific intermediates in proliferation, mitochondrial function and cellular morphology in procyclic cells. A decrease in the levels of squalene synthase and squalene epoxidase resulted in a depletion of cellular sterol intermediates and end products, impaired cell growth and led to aberrant morphologies, DNA fragmentation and a profound modification of mitochondrial structure and function. In contrast, cells deficient in sterol methyl transferase, the enzyme involved in 24-alkylation, exhibited a normal growth phenotype in spite of a complete abolition of the synthesis and content of 24-alkyl sterols. Thus, the data provided indicates that while the depletion of squalene and post-squalene endogenous sterol metabolites results in profound cellular defects, bulk 24-alkyl sterols are not strictly required to support growth in insect forms of T. brucei in vitro. Copyright © 2012 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Overdeterminacy and endogenous cycles: Trygve Haavelmo’s business cycle model and its implications for monetary policy

OpenAIRE

Kallåk Anundsen , André; Sigurd Holmsen Krogh, Tord; Nymoen, Ragnar; Vislie, Jon

2011-01-01

This paper presents the business cycle model that Trygve Haavelmo developed as part of his research program in macroeconomic and monetary theory. Driven by a mismatch between the marginal return to capital and the rate of return required by capital owners, this model generates endogenous cycles. The theory leads to a distinct analysis of the scope and limitations of monetary policy. A main message of the model is that care should be taken when conducting 'autonomous' monetary policy and that ...

ECONOMIC gROWTH, GLOBALIZATION AND TRADE

OpenAIRE

Nuno Carlos LEITÃO

2012-01-01

The purpose of this article is to investigate the relationship between economic growth, globalization and trade. The manuscript uses the assumptions of the economic growth exogenous and endogenous models. It introduces new proxies for explain the economic growth as in intra-industry trade, foreign direct investment and globalization index. The results indicate that economic growth is a dynamic process. The intra-industry has a positive impact on economic growth. This paper confirms relevan...

Analysis of the neutrons dispersion in a semi-infinite medium based in transport theory and the Monte Carlo method; Analisis de la dispersion de neutrones en un medio semi-infinito en base a teoria de transporte y el metodo de Monte Carlo

Energy Technology Data Exchange (ETDEWEB)

Arreola V, G. [IPN, Escuela Superior de Fisica y Matematicas, Posgrado en Ciencias Fisicomatematicas, area en Ingenieria Nuclear, Unidad Profesional Adolfo Lopez Mateos, Edificio 9, Col. San Pedro Zacatenco, 07730 Mexico D. F. (Mexico); Vazquez R, R.; Guzman A, J. R., E-mail: energia.arreola.uam@gmail.com [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Area de Ingenieria en Recursos Energeticos, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico)

2012-10-15

In this work a comparative analysis of the results for the neutrons dispersion in a not multiplicative semi-infinite medium is presented. One of the frontiers of this medium is located in the origin of coordinates, where a neutrons source in beam form, i.e., {mu}{omicron}=1 is also. The neutrons dispersion is studied on the statistical method of Monte Carlo and through the unidimensional transport theory and for an energy group. The application of transport theory gives a semi-analytic solution for this problem while the statistical solution for the flow was obtained applying the MCNPX code. The dispersion in light water and heavy water was studied. A first remarkable result is that both methods locate the maximum of the neutrons distribution to less than two mean free trajectories of transport for heavy water, while for the light water is less than ten mean free trajectories of transport; the differences between both methods is major for the light water case. A second remarkable result is that the tendency of both distributions is similar in small mean free trajectories, while in big mean free trajectories the transport theory spreads to an asymptote value and the solution in base statistical method spreads to zero. The existence of a neutron current of low energy and toward the source is demonstrated, in contrary sense to the neutron current of high energy coming from the own source. (Author)

Tax Havens, Growth, and Welfare

OpenAIRE

Chu, Hsun; Lai, Ching-Chong; Cheng, Chu-Chuan

2013-01-01

This paper develops an endogenous growth model featuring tax havens, and uses it to examine how the existence of tax havens affects the economic growth rate and social welfare in high-tax countries. We show that the presence of tax havens generates two conflicting channels in determining the growth effect. First, the public investment effect states that tax havens may erode tax revenues and in turn decrease the government’s infrastructure expenditure, thereby reducing growth. Second, the t...

Illustrated study of the semi-holographic non-perturbative framework

NARCIS (Netherlands)

Banerjee, Souvik; Gaddam, Nava; Mukhopadhyay, Ayan

2017-01-01

Semi-holography has been proposed as an effective nonperturbative framework which can combine perturbative and nonperturbative effects consistently for theories like QCD. It is postulated that the strongly coupled nonperturbative sector has a holographic dual in the form of a classical gravity

Interior beam searchlight semi-analytical benchmark

International Nuclear Information System (INIS)

Ganapol, Barry D.; Kornreich, Drew E.

2008-01-01

Multidimensional semi-analytical benchmarks to provide highly accurate standards to assess routine numerical particle transport algorithms are few and far between. Because of the well-established 1D theory for the analytical solution of the transport equation, it is sometimes possible to 'bootstrap' a 1D solution to generate a more comprehensive solution representation. Here, we consider the searchlight problem (SLP) as a multidimensional benchmark. A variation of the usual SLP is the interior beam SLP (IBSLP) where a beam source lies beneath the surface of a half space and emits directly towards the free surface. We consider the establishment of a new semi-analytical benchmark based on a new FN formulation. This problem is important in radiative transfer experimental analysis to determine cloud absorption and scattering properties. (authors)

Fatigue crack growth behaviour of semi-elliptical surface cracks for an API 5L X65 gas pipeline under tension

Science.gov (United States)

Shaari, M. S.; Akramin, M. R. M.; Ariffin, A. K.; Abdullah, S.; Kikuchi, M.

2018-02-01

The paper is presenting the fatigue crack growth (FCG) behavior of semi-elliptical surface cracks for API X65 gas pipeline using S-version FEM. A method known as global-local overlay technique was used in this study to predict the fatigue behavior that involve of two separate meshes each specifically for global (geometry) and local (crack). The pre-post program was used to model the global geometry (coarser mesh) known as FAST including the material and boundary conditions. Hence, the local crack (finer mesh) will be defined the exact location and the mesh control accordingly. The local mesh was overlaid along with the global before the numerical computation taken place to solve the engineering problem. The stress intensity factors were computed using the virtual crack closure-integral method (VCCM). The most important results is the behavior of the fatigue crack growth, which contains the crack depth (a), crack length (c) and stress intensity factors (SIF). The correlation between the fatigue crack growth and the SIF shows a good growth for the crack depth (a) and dissimilar for the crack length (c) where stunned behavior was resulted. The S-version FEM will benefiting the user due to the overlay technique where it will shorten the computation process.

Time-dependent changes of levels of endogenous epidermal growth factor in submandibular glands, in kidneys, and in urine in rats during systemic treatment with EGF

DEFF Research Database (Denmark)

Vinter-Jensen, Lars; Jørgensen, P E; Thulesen, J

1998-01-01

Exogenous EGF influences the levels of endogenous EGF differently in the submandibular glands (SMG) and the kidneys. The aim of the present study was to examine the time-dependent changes in levels of endogenous EGF during 1-4 weeks of EGF treatment.......Exogenous EGF influences the levels of endogenous EGF differently in the submandibular glands (SMG) and the kidneys. The aim of the present study was to examine the time-dependent changes in levels of endogenous EGF during 1-4 weeks of EGF treatment....

The explicit form of the rate function for semi-Markov processes and its contractions

Science.gov (United States)

Sughiyama, Yuki; Kobayashi, Testuya J.

2018-03-01

We derive the explicit form of the rate function for semi-Markov processes. Here, the ‘random time change trick’ plays an essential role. Also, by exploiting the contraction principle of large deviation theory to the explicit form, we show that the fluctuation theorem (Gallavotti-Cohen symmetry) holds for semi-Markov cases. Furthermore, we elucidate that our rate function is an extension of the level 2.5 rate function for Markov processes to semi-Markov cases.

Protein-releasing polymeric scaffolds induce fibrochondrocytic differentiation of endogenous cells for knee meniscus regeneration in sheep

Science.gov (United States)

Lee, Chang H.; Rodeo, Scott A.; Fortier, Lisa Ann; Lu, Chuanyong; Erisken, Cevat

2015-01-01

Regeneration of complex tissues, such as kidney, liver, and cartilage, continues to be a scientific and translational challenge. Survival of ex vivo cultured, transplanted cells in tissue grafts is among one of the key barriers. Meniscus is a complex tissue consisting of collagen fibers and proteoglycans with gradient phenotypes of fibrocartilage and functions to provide congruence of the knee joint, without which the patient is likely to develop arthritis. Endogenous stem/progenitor cells regenerated the knee meniscus upon spatially released human connective tissue growth factor (CTGF) and transforming growth factor–β3 (TGFβ3) from a three-dimensional (3D)–printed biomaterial, enabling functional knee recovery. Sequentially applied CTGF and TGFβ3 were necessary and sufficient to propel mesenchymal stem/progenitor cells, as a heterogeneous population or as single-cell progenies, into fibrochondrocytes that concurrently synthesized procollagens I and IIα. When released from microchannels of 3D–printed, human meniscus scaffolds, CTGF and TGFβ3 induced endogenous stem/progenitor cells to differentiate and synthesize zone-specific type I and II collagens. We then replaced sheep meniscus with anatomically correct, 3D–printed scaffolds that incorporated spatially delivered CTGF and TGFβ3. Endogenous cells regenerated the meniscus with zone-specific matrix phenotypes: primarily type I collagen in the outer zone, and type II collagen in the inner zone, reminiscent of the native meniscus. Spatiotemporally delivered CTGF and TGFβ3 also restored inhomogeneous mechanical properties in the regenerated sheep meniscus. Survival and directed differentiation of endogenous cells in a tissue defect may have implications in the regeneration of complex (heterogeneous) tissues and organs. PMID:25504882

A semi-Dirac point and an electromagnetic topological transition in a dielectric photonic crystal

KAUST Repository

Wu, Ying

2014-01-01

Accidental degeneracy in a photonic crystal consisting of a square array of elliptical dielectric cylinders leads to both a semi-Dirac point at the center of the Brillouin zone and an electromagnetic topological transition (ETT). A perturbation method is deduced to affirm the peculiar linear-parabolic dispersion near the semi-Dirac point. An effective medium theory is developed to explain the simultaneous semi-Dirac point and ETT and to show that the photonic crystal is either a zero-refractive-index material or an epsilon-near-zero material at the semi-Dirac point. Drastic changes in the wave manipulation properties at the semi-Dirac point, resulting from ETT, are described.©2014 Optical Society of America.

Entanglement growth after a global quench in free scalar field theory

Energy Technology Data Exchange (ETDEWEB)

Cotler, Jordan S. [Stanford Institute for Theoretical Physics, Department of Physics, Stanford University, Stanford, CA 94305 (United States); Hertzberg, Mark P. [Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States); Mezei, Márk [Princeton Center for Theoretical Science, Princeton University, Princeton, NJ 08544 (United States); Mueller, Mark T. [Center for Theoretical Physics, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

2016-11-28

We compute the entanglement and Rényi entropy growth after a global quench in various dimensions in free scalar field theory. We study two types of quenches: a boundary state quench and a global mass quench. Both of these quenches are investigated for a strip geometry in 1, 2, and 3 spatial dimensions, and for a spherical geometry in 2 and 3 spatial dimensions. We compare the numerical results for massless free scalars in these geometries with the predictions of the analytical quasiparticle model based on EPR pairs, and find excellent agreement in the limit of large region sizes. At subleading order in the region size, we observe an anomalous logarithmic growth of entanglement coming from the zero mode of the scalar.

EVOLUTION OF THEORIES AND EMPIRICAL MODELS OF A RELATIONSHIP BETWEEN ECONOMIC GROWTH, SCIENCE AND INNOVATIONS (PART I

Directory of Open Access Journals (Sweden)

Kaneva M. A.

2017-12-01

Full Text Available This article is a first chapter of an analytical review of existing theoretical models of a relationship between economic growth / GRP and indicators of scientific development and innovation activities, as well as empirical approaches to testing this relationship. Aim of the paper is a systematization of existing approaches to modeling of economic growth geared by science and innovations. The novelty of the current review lies in the authors’ criteria of interconnectedness of theoretical and empirical studies in the systematization of a wide range of publications presented in a final table-scheme. In the first part of the article the authors discuss evolution of theoretical approaches, while the second chapter presents a time gap between theories and their empirical verification caused by the level of development of quantitative instruments such as econometric models. The results of this study can be used by researchers and graduate students for familiarization with current scientific approaches that manifest progress from theory to empirical verification of a relationship «economic growth-innovations» for improvement of different types of models in spatial econometrics. To apply these models to management practices the presented review could be supplemented with new criteria for classification of knowledge production functions and other theories about effect of science on economic growth.

Work Motivation: Theory and Practice.

Science.gov (United States)

Katzell, Raymond A.; Thompson, Donna E.

1990-01-01

Presents theories of motivation classified as those dealing either with exogenous causes or with endogenous processes. The following strategies for improving work motivation are discussed: (1) personal motives; (2) incentives and rewards; (3) reinforcement; (4) goal-setting techniques; (5) personal and material resources; (6) social and group…

Ciliary neurotrophic factor is an endogenous pyrogen.

Science.gov (United States)

Shapiro, L; Zhang, X X; Rupp, R G; Wolff, S M; Dinarello, C A

1993-09-15

Fever is initiated by the action of polypeptide cytokines called endogenous pyrogens, which are produced by the host during inflammation, trauma, or infection and which elevate the thermoregulatory set point in the hypothalamus. Ciliary neurotrophic factor (CNTF) supports the differentiation and survival of central and peripheral neurons. We describe the activity of CNTF as intrinsically pyrogenic in the rabbit. CNTF induced a monophasic fever which rose rapidly (within the first 12 min) following intravenous injection; CNTF fever was blocked by pretreatment with indomethacin. The fever induced by CNTF was not due to contaminating endotoxins. Increasing doses of CNTF resulted in prolongation of the fever, suggesting the subsequent induction of additional endogenous pyrogenic activity. After passive transfer of plasma obtained during CNTF-induced fever, endogenous pyrogen activity was not present in the circulation; CNTF also did not induce the endogenous pyrogens interleukin 1, tumor necrosis factor, or interleukin 6 in vitro. Nevertheless, a second endogenous pyrogen may originate within the central nervous system following the systemic injection of CNTF. Of the four endogenous pyrogens described to date (interleukin 1, tumor necrosis factor, interferon, and interleukin 6), CNTF, like interleukin 6, utilizes the cell-surface gp 130 signal-transduction apparatus.

Semi-classical theory of fluctuations in nuclear matter; Theorie semi-classique des fluctuations dans la matiere nucleaire

Energy Technology Data Exchange (ETDEWEB)

Benhassine, B. [Nantes Univ., 44 (France)

1994-01-14

At intermediate energies the heavy ion collisions can be studied within the framework of a semi-classical approach based on the Vlasov-Uehling-Uhlenbeck (VUU) equation. Such an approach reduces the N-body problem to its description in terms of the one-body distribution function and constitutes the basis of several successful simulation models. Our aim in this work is to extend these average approaches to treat fluctuations. Within the framework of a linear approximation, we derived a Fokker-Planck transport equation in the one-body phase space. When it is reduced to its first moments, one recovers the VUU equation for the average dynamics together with the time evolution equation for the correlations. The collective transport coefficients are then obtained by projection on the one-body collective space. Independently, using a projection method introduced by Van Kampen, based on the constants of motion, we deduce the stationary expressions for the covariance matrix in phase space. We extract then, the equilibrium dispersions of one-body observables in a homogeneous case and in a spherical symmetric one. These results are compared with two types of simulation models in a relaxation time approximation. In the first one which is of Lagrangian type, the collective transport coefficients are directly extracted from the simulation and consequently the numerical fluctuations are washed out. The second model, due to its Eulerian character, allows us to make a microscopical comparison. (author) 58 refs.

Semi-supervised and unsupervised extreme learning machines.

Science.gov (United States)

Huang, Gao; Song, Shiji; Gupta, Jatinder N D; Wu, Cheng

2014-12-01

Extreme learning machines (ELMs) have proven to be efficient and effective learning mechanisms for pattern classification and regression. However, ELMs are primarily applied to supervised learning problems. Only a few existing research papers have used ELMs to explore unlabeled data. In this paper, we extend ELMs for both semi-supervised and unsupervised tasks based on the manifold regularization, thus greatly expanding the applicability of ELMs. The key advantages of the proposed algorithms are as follows: 1) both the semi-supervised ELM (SS-ELM) and the unsupervised ELM (US-ELM) exhibit learning capability and computational efficiency of ELMs; 2) both algorithms naturally handle multiclass classification or multicluster clustering; and 3) both algorithms are inductive and can handle unseen data at test time directly. Moreover, it is shown in this paper that all the supervised, semi-supervised, and unsupervised ELMs can actually be put into a unified framework. This provides new perspectives for understanding the mechanism of random feature mapping, which is the key concept in ELM theory. Empirical study on a wide range of data sets demonstrates that the proposed algorithms are competitive with the state-of-the-art semi-supervised or unsupervised learning algorithms in terms of accuracy and efficiency.

Model of emittance growth in a self-pinched beam

International Nuclear Information System (INIS)

Lee, E.P.; Yu, S.S.

1979-01-01

A semi-phenomenological formula is proposed for the change of emittance of a self-pinched beam which is not matched to its equilibrium radius. Near equilibrium this formula, coupled with an envelope equation, yields the damped sausage oscillations observed in simulation and experiments. For a beam which is injected cold (no transverse velocity spread), the formula coincides with the analytically calculated initial growth of emittance. The basic theory is developed here and used to compute the linear damping rate for several current profiles. The resultant non-linear increase in equilibrium quantities is also calculated in lowest order of the degree of mismatch

Endogenous GAS6 and Mer receptor signaling regulate prostate cancer stem cells in bone marrow.

Science.gov (United States)

Jung, Younghun; Decker, Ann M; Wang, Jingcheng; Lee, Eunsohl; Kana, Lulia A; Yumoto, Kenji; Cackowski, Frank C; Rhee, James; Carmeliet, Peter; Buttitta, Laura; Morgan, Todd M; Taichman, Russell S

2016-05-03

GAS6 and its receptors (Tryo 3, Axl, Mer or "TAM") are known to play a role in regulating tumor progression in a number of settings. Previously we have demonstrated that GAS6 signaling regulates invasion, proliferation, chemotherapy-induced apoptosis of prostate cancer (PCa) cells. We have also demonstrated that GAS6 secreted from osteoblasts in the bone marrow environment plays a critical role in establishing prostate tumor cell dormancy. Here we investigated the role that endogenous GAS6 and Mer receptor signaling plays in establishing prostate cancer stem cells in the bone marrow microenvironment.We first observed that high levels of endogenous GAS6 are expressed by disseminated tumor cells (DTCs) in the bone marrow, whereas relatively low levels of endogenous GAS6 are expressed in PCa tumors grown in a s.c. Interestingly, elevated levels of endogenous GAS6 were identified in putative cancer stem cells (CSCs, CD133+/CD44+) compared to non-CSCs (CD133-/CD44-) isolated from PCa/osteoblast cocultures in vitro and in DTCs isolated from the bone marrow 24 hours after intracardiac injection. Moreover, we found that endogenous GAS6 expression is associated with Mer receptor expression in growth arrested (G1) PCa cells, which correlates with the increase of the CSC populations. Importantly, we found that overexpression of GAS6 activates phosphorylation of Mer receptor signaling and subsequent induction of the CSC phenotype in vitro and in vivo.Together these data suggest that endogenous GAS6 and Mer receptor signaling contribute to the establishment of PCa CSCs in the bone marrow microenvironment, which may have important implications for targeting metastatic disease.

Theories of nucleation and growth of bubbles and voids

International Nuclear Information System (INIS)

Speight, M.V.

1977-01-01

The application of classical nucleation theory to the formation of voids from a supersaturated concentration of vacancies is reviewed. The effect of a dissolved concentration of barley soluble gas on the nucleation rate of voids is emphasized. Exposure to a damaging flux of irradiation is the most effective way of introducing a vacancy supersaturation, but interstitials are produced at an equal rate. The concentration of interstitials inhibits the nucleation of voids which can occur only in the presence of dislocations since they preferentially absorb interstitials. It is well known that a definite value of internal gas pressure is necessary to stabilize a bubble so that it shows no tendencies to either shrink or grow. The arguments are reviewed which conclude that this pressure is determined by the specific surface free energy of the solid rather than the surface tension. While the former property refers to the energy necessary to create new surface, the latter is a measure of the work done in elastically stretching a a given surface. The presence of an equilibrium gas bubble leaves the stresses in the surrounding solid unperturbed only when surface energy and surface tension are numerically equal. A bubble with internal pressure greater than the restraint offered by surface energy tends to grow to relieve the excess pressure. The mechanism of growth can involve the migration of vacancies from remote sources to the bubble surface or the plastic straining of the solid surrounding the bubble. The kinetics of both mechanisms are developed and compared. The theory of growth of grain-boundary voids by vacancy condensation under an applied stress is also considered. (author)

Growing up and role modeling: a theory in Iranian nursing students' education.

Science.gov (United States)

Mokhtari Nouri, Jamileh; Ebadi, Abbas; Alhani, Fatemeh; Rejeh, Nahid

2014-11-16

One of the key strategies in students' learning is being affected by models. Understanding the role-modeling process in education will help to make greater use of this training strategy. The aim of this grounded theory study was to explore Iranian nursing students and instructors' experiences about role modeling process. Data was analyzed by Glaserian's Grounded Theory methodology through semi-structured interviews with 7 faculty members, 2 nursing students; the three focus group discussions with 20 nursing students based on purposive and theoretical sampling was done for explaining role modeling process from four nursing faculties in Tehran. Through basic coding, an effort to comprehensive growth and excellence was made with the basic social process consisting the core category and through selective coding three phases were identified as: realizing and exposure to inadequate human and professional growth, facilitating human and professional growth and evolution. The role modeling process is taking place unconscious, involuntary, dynamic and with positive progressive process in order to facilitate overall growth in nursing student. Accordingly, the design and implementation of the designed model can be used to make this unconscious to conscious, active and voluntarily processes a process to help education administrators of nursing colleges and supra organization to prevent threats to human and professional in nursing students' education and promote nursing students' growth.

Optimal Incentives in a Principal–Agent Model with Endogenous Technology

Directory of Open Access Journals (Sweden)

Marco A. Marini

2018-02-01

Full Text Available One of the standard predictions of the agency theory is that more incentives can be given to agents with lower risk aversion. In this paper, we show that this relationship may be absent or reversed when the technology is endogenous and projects with a higher efficiency are also riskier. Using a modified version of the Holmstrom and Milgrom’s framework, we obtain that lower agent’s risk aversion unambiguously leads to higher incentives when the technology function linking efficiency and riskiness is elastic, while the risk aversion–incentive relationship can be positive when this function is rigid.

Clinical study of the hypothesis of endogenous collateral wind on acute coronary syndrome: a review.

Science.gov (United States)

Wang, Xian; Zhang, Cong; Yang, Ran; Zhu, Haiyan; Zhao, Huaibing; Li, Xiaoming

2014-01-01

Acute Coronary Syndrome (ACS), is a serious threat to people's health, and life, and in recent years, the incidence has increased yearly. This study was to propose the hypothesis of "endogenous collateral wind" based on the patho-mechanism of thrombogenesis complicated by ruptured plaque on ACS, and the theory of traditional Chinese medicine. Through successful coronary angiography (CAG), and intravascular ultrasound (IVUS), patients with coronary artery disease were made the differential diagnosis such as blood stasis, blood stasis due to phlegm obstruction, and endogenous collateral wind. The levels of plasma inflammatory marker were measured to study on the characteristics of "endogenous collateral wind". Luo heng dripping pills with promoting blood circulation to expel wind-evil, and remove wetness were made based on the hypothesis of "endogenous collateral wind" on ACS. Patients with unstable angina were randomly divided into 3, groups based on therapeutic methods: conventional therapy group, Luo Heng dripping pills group and Tongxinluo caps. Differences among groups were compared. There were great changes in number and degree of coronary arteriostenosis confirmed by CAG, the types of ACC/AHA lesion and Levin lesion confirmed by CAG, remodeling index, positive or negative remodeling percentage measured by IVUS, the plasma levels of plasma inflammatory marker measured by ELLSA in the patients with endogenous collateral wind, compared with patients with blood stasis and blood stasis due to phlegm obstruction. The total effective rate of improved angina in Luo Heng dripping pills group was significantly higher than those in other two groups. The levels of plasma inflammatory marker were significantly lower in Luo Heng dripping pills group. There were some pathological basis which were found about the hypothesis of "endogenous collateral wind" on acute coronary syndrome. It provided evidences for patients with coronary artery disease treated by medicines with

A positive semi-definite action in a Kaluza-Klein theory with compactification onto time-like extra dimensions

International Nuclear Information System (INIS)

Pollock, M.D.

1986-01-01

We consider the (4+N)-dimensional theory whose Lagrangian function is Lsub(4+N)=√-g-circumflex α R-circumflex 2 , where R-circumflex is the Ricci scalar and α is a positive constant. The metric is g-circumflexsub(AB)= diag(gsub(ab), phi -1 g-barsub(mn)). Dimensional reduction leads to an effective four-dimensional Lagrangian of induced-gravity type. The positive semi-definiteness of L avoids the difficulties, pointed out recently by Horowitz and by Rubakov, which can arise in quantum cosmology when the (Euclidean) action becomes negative. The compactification is onto a time-like internal space g-barsub(mn), as suggested by Aref'eva and Volovich, giving a four-dimensional de Sitter space-time with phi=constant, which however is classically unstable on a time scale approx. H -1 . Decrease of the radius phisup(-1/2) of the internal space is ultimately halted by quantum effects, via some V(phi), and L 4 then includes the usual Hilbert term and a cosmological constant. (author)

Semi-polar GaN heteroepitaxy an high index Si-surfaces

Energy Technology Data Exchange (ETDEWEB)

Ravash, Roghaiyeh; Blaesing, Juergen; Hempel, Thomas; Dadgar, Armin; Christen, Juergen; Krost, Alois [Otto-von-Guericke-University Magdeburg, FNW/IEP/AHE, Magdeburg (Germany)

2011-07-01

Due to the lack of GaN homosubstrates, the growth of GaN-based devices is usually performed on heterosubstrates as sapphire or SiC. These substrates are either insulating or expensive, and both unavailable in large diameters. Meanwhile, silicon can meet the requirements for a low price and thermally well conducting substrate and also enabling the integration of optoelectronic devices with Si-based electronics. Up to now, the good matching of hexagonal GaN with the three-fold symmetry of Si(111) greatly promotes the c-axis orientated growth of GaN on this surface plane. A large spontaneous and piezoelectric polarization oriented along the c-axis exists in such hexagonal structure leading to low efficiencies for thick quantum wells. The attention to the growth of non-polar or semi-polar GaN based epitaxial structures has been increased recently because of reducing the effect of the polarization fields in these growth directions. Therefore we studied semi-polar GaN epilayers grown by metalorganic vapor phase epitaxy on silicon substrates with different orientations from Si(211) to Si(711). We observed that AlN seeding layer growth time play a significant role in obtaining the different GaN texture.

Increased water use efficiency does not prevent growth decline of Pinus canariensis in a semi-arid treeline ecotone in Tenerife, Canary Islands (Spain).

Science.gov (United States)

Brito, Patricia; Grams, Thorsten E E; Matysssek, Rainer; Jimenez, Maria S; Gonzalez-Rodríguez, Agueda M; Oberhuber, Walter; Wieser, Gerhard

2016-09-01

Intrinsic water-use efficiency of Pinus canariensis (Sweet ex Spreng.) growing at a semi-arid treeline has increased during the past 37 years. Tree-ring width by contrast has declined, likely caused by reduced stomatal conductance due to increasing aridity. Rising atmospheric CO 2 concentration ( C a ) has been related to tree growth enhancement accompanied by increasing intrinsic water-use-efficiency (iWUE). Nevertheless, the extent of rising C a on long-term changes in iWUE and growth has remained poorly understood to date in Mediterranean treeline ecosystems. This study aimed to examine radial growth and physiological responses of P. canariensis in relation to rising C a and increasing aridity at treeline in Tenerife, Canary Islands, Spain. We evaluated temporal changes in secondary growth (tree-ring width; TRW) and tree ring stable C isotope signature for assessing iWUE from 1975 through 2011. Precipitation was the main factor controlling secondary growth. Over the last 36 years P. canariensis showed a decline in TRW at enhanced iWUE, likely caused by reduced stomatal conductance due to increasing aridity. Our results indicate that increasing aridity has overridden the potential CO 2 fertilization on tree growth of P. canariensis at its upper distribution limit.

The point ground electrode in vicinity of the semi-spherical inhomogenity

Directory of Open Access Journals (Sweden)

Cvetković Nenad N.

2005-01-01

Full Text Available Characterization of the point ground electrode placed in the surroundings or inside of the semi-spherical earth inhomogenity and fed by low frequency (LF current using isolated earthling conductor, is presented in this paper. The ground impedance (resistance and reactance and potential distribution on the ground surface are determined. Image theory for two-layer semi conducting media, as well as for the one point electrode placed nearby or inside of the spherical body is used during the analysis.

Mass deformed world-sheet action of semi local vortices

Energy Technology Data Exchange (ETDEWEB)

Jiang, Yunguo [School of Space Science and Physics, Shandong University at Weihai,264209 Weihai (China); Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment,264209 Weihai (China)

2014-02-10

The mass deformed effective world-sheet theory of semi local vortices was constructed via the field theoretical method. By Euler-Lagrangian equations, the Ansatze for both the gauge field and the adjoint scalar were solved, this ensures that zero modes of vortices are minimal excitations of the system. Up to the 1/g{sup 2} order, all profiles are solved. The mass deformed effective action was obtained by integrating out the transverse plane of the vortex string. The effective theory interpolates between the local vortex and the lump. Respecting certain normalization conditions, the effective theory shows a Seiberg-like duality, which agrees with the result of the Kähler quotient construction.

Microbiological quality of soft, semi-hard and hard cheeses during the shelf-life

Directory of Open Access Journals (Sweden)

Josip Vrdoljak

2016-03-01

Full Text Available Cheeses as ready-to-eat food should be considered as a potential source of foodborne pathogens, primarily Listeria monocytogenes. The aim of present study was to determine the microbiological quality of soft, semi-hard and hard cheeses during the shelf-life, with particular reference to L. monocytogenes. Five types of cheeses were sampled at different timepoints during the cold storage and analyzed for presence of Salmonella and L. monocytogenes, as well as lactic acid bacteria, Escherichia coli, coagulase-positive staphylococci, yeasts, molds, sulfite-reducing clostridia and L. monocytogenes counts. Water activity, pH and NaCl content were monitored in order to evaluate the possibility of L. monocytogenes growth. Challenge test for L. monocytogenes was performed in soft whey cheese, to determine the growth potential of pathogen during the shelf-life of product. All analyzed cheeses were compliant with microbiological criteria during the shelf-life. In soft cheeses, lactic acid bacteria increased in the course of the shelf-life period (1.2-2.6 log increase, while in semi-hard and hard cheeses it decreased (1.6 and 5.2 log decrease, respectively. Soft cheeses support the growth of L. monocytogenes according to determined pH values (5.8-6.5, water activity (0.99-0.94, and NaCl content (0.3-1.2%. Challenge test showed that L. monocytogenes growth potential in selected soft cheese was 0.43 log10 cfu/g during 8 days at 4°C. Water activity in semi-hard and hard cheeses was a limiting factor for Listeria growth during the shelf-life. Soft, semi-hard and hard cheeses were microbiologically stable during their defined shelf-life. Good manufacturing and hygienic practices must be strictly followed in the production of soft cheeses as Listeria-supporting food and be focused on preventing (recontamination.

Synthesis of the semi-organic nonlinear optical crystal l-glutamic acid zinc chloride and investigation of its growth and physiochemical properties

Directory of Open Access Journals (Sweden)

S. Chennakrishnan

2017-11-01

Full Text Available The aim of this study is to synthesize and investigate the growth and physiochemical properties of the nonlinear optical semi-organic crystal l-glutamic acid zinc chloride (LGAZC. An optically transparent and defect-free crystal was grown with the slow evaporation solution growth technique under optimized conditions. The induction periods were measured at various supersaturations, and the interfacial energies were evaluated. Single crystal X-ray diffraction reveals that the crystal has an orthorhombic structure with space group P212121, and the calculated lattice parameters are a = 5.20 Å, b = 6.99 Å, c = 17.58 Å, α = β = γ = 90° and volume = 623.411 Å3. Spectroscopic properties were investigated by recording the Fourier transform infrared and optical transmission spectra. The thermal decomposition of the grown crystal was investigated by Thermo Gravimetric and Differential Thermal Analysis (TG/DTA. The LGAZC crystal exhibits second harmonic generation (SHG efficiency 1.5 times that of inorganic KDP crystal. The presence of the metal ion (Zn+ in a grown crystal was identified by EDAX spectrum analysis. The photoconductivity study demonstrates that LGAZC crystal has a positive photo conducting nature. The dielectric response of the LGAZC crystal was investigated and reported. Keywords: Semi-organic nonlinear optical crystal, X-ray Diffraction, UV-vis-NIR, Thermal study

Endogenous and exogenous control of ecosystem function: N cycling in headwater streams

Energy Technology Data Exchange (ETDEWEB)

Mulholland, Patrick J [ORNL; Valett, H. Maurice [Virginia Polytechnic Institute and State University (Virginia Tech); Thomas, Steve [University of Nebraska; Webster, Jackson [Virginia Polytechnic Institute and State University (Virginia Tech); Dahm, Cliff [University of New Mexico, Albuquerque; Fellows, Christine [Griffith University, Nathan, Queensland, Australia; Crenshaw, Chelsea [University of New Mexico, Albuquerque; Peterson, Chris G. [Loyola University

2008-01-01

Allochthonous inputs act as resource subsidies to many ecosystems, where they exert strong influences on metabolism and material cycling. At the same time, metabolic theory proposes endogenous thermal control independent of resource supply. To address the relative importance of exogenous and endogenous influences, we quantified spatial and temporal variation in ecosystem metabolism and nitrogen (N) uptake using seasonal releases of {sup 15}N as nitrate in six streams differing in riparian-stream interaction and metabolic character. Nitrate removal was quantified using a nutrient spiraling approach based on measurements of downstream decline in {sup 15}N flux. Respiration (R) and gross primary production (GPP) were measured with whole-stream diel oxygen budgets. Uptake and metabolism metrics were addressed as z scores relative to site means to assess temporal variation. In open-canopied streams, areal uptake (U; {micro}g N {center_dot} m{sup -2} {center_dot} s{sup -1}) was closely related to GPP, metabolic rates increased with temperature, and R was accurately predicted by metabolic scaling relationships. In forested streams, N spiraling was not related to GPP; instead, uptake velocity (v{sub f}; mm/s) was closely related to R. In contrast to open-canopied streams, N uptake and metabolic activity were negatively correlated to temperature and poorly described by scaling laws. We contend that streams differ along a gradient of exogenous and endogenous control that relates to the relative influences of resource subsidies and in-stream energetics as determinants of seasonal patterns of metabolism and N cycling. Our research suggests that temporal variation in the propagation of ecological influence between adjacent systems generates phases when ecosystems are alternatively characterized as endogenously and exogenously controlled.

Endogenous and exogenous control of ecosystem function: N cycling in headwater streams.

Science.gov (United States)

Valett, H M; Thomas, S A; Mulholland, P J; Webster, J R; Dahm, C N; Fellows, C S; Crenshaw, C L; Peterson, C G

2008-12-01

Allochthonous inputs act as resource subsidies to many ecosystems, where they exert strong influences on metabolism and material cycling. At the same time, metabolic theory proposes endogenous thermal control independent of resource supply. To address the relative importance of exogenous and endogenous influences, we quantified spatial and temporal variation in ecosystem metabolism and nitrogen (N) uptake using seasonal releases of 15N as nitrate in six streams differing in riparian-stream interaction and metabolic character. Nitrate removal was quantified using a nutrient spiraling approach based on measurements of downstream decline in 15N flux. Respiration (R) and gross primary production (GPP) were measured with whole-stream diel oxygen budgets. Uptake and metabolism metrics were addressed as z scores relative to site means to assess temporal variation. In open-canopied streams, areal uptake (U; microg N x m(-2) x s(-1)) was closely related to GPP, metabolic rates increased with temperature, and R was accurately predicted by metabolic scaling relationships. In forested streams, N spiraling was not related to GPP; instead, uptake velocity (v(f); mm/s) was closely related to R. In contrast to open-canopied streams, N uptake and metabolic activity were negatively correlated to temperature and poorly described by scaling laws. We contend that streams differ along a gradient of exogenous and endogenous control that relates to the relative influences of resource subsidies and in-stream energetics as determinants of seasonal patterns of metabolism and N cycling. Our research suggests that temporal variation in the propagation of ecological influence between adjacent systems generates phases when ecosystems are alternatively characterized as endogenously and exogenously controlled.

A model analysis of climate and CO2 controls on tree growth in a semi-arid woodland

Science.gov (United States)

Li, G.; Harrison, S. P.; Prentice, I. C.

2015-03-01

We used a light-use efficiency model of photosynthesis coupled with a dynamic carbon allocation and tree-growth model to simulate annual growth of the gymnosperm Callitris columellaris in the semi-arid Great Western Woodlands, Western Australia, over the past 100 years. Parameter values were derived from independent observations except for sapwood specific respiration rate, fine-root turnover time, fine-root specific respiration rate and the ratio of fine-root mass to foliage area, which were estimated by Bayesian optimization. The model reproduced the general pattern of interannual variability in radial growth (tree-ring width), including the response to the shift in precipitation regimes that occurred in the 1960s. Simulated and observed responses to climate were consistent. Both showed a significant positive response of tree-ring width to total photosynthetically active radiation received and to the ratio of modeled actual to equilibrium evapotranspiration, and a significant negative response to vapour pressure deficit. However, the simulations showed an enhancement of radial growth in response to increasing atmospheric CO2 concentration (ppm) ([CO2]) during recent decades that is not present in the observations. The discrepancy disappeared when the model was recalibrated on successive 30-year windows. Then the ratio of fine-root mass to foliage area increases by 14% (from 0.127 to 0.144 kg C m-2) as [CO2] increased while the other three estimated parameters remained constant. The absence of a signal of increasing [CO2] has been noted in many tree-ring records, despite the enhancement of photosynthetic rates and water-use efficiency resulting from increasing [CO2]. Our simulations suggest that this behaviour could be explained as a consequence of a shift towards below-ground carbon allocation.

Interaction between endogenous and exogenous orienting in crossmodal attention.

Science.gov (United States)

Chen, Xiaoxi; Chen, Qi; Gao, Dingguo; Yue, Zhenzhu

2012-08-01

Using a cue-target paradigm, we investigated the interaction between endogenous and exogenous orienting in cross-modal attention. A peripheral (exogenous) cue was presented after a central (endogenous) cue with a variable time interval. The endogenous and exogenous cues were presented in one sensory modality (auditory in Experiment 1 and visual in Experiment 2) whereas the target was presented in another modality. Both experiments showed a significant endogenous cuing effect (longer reaction times in the invalid condition than in the valid condition). However, exogenous cuing produced a facilitatory effect in both experiments in response to the target when endogenous cuing was valid, but it elicited a facilitatory effect in Experiment 1 and an inhibitory effect in Experiment 2 when endogenous cuing was invalid. These findings indicate that endogenous and exogenous cuing can co-operate in orienting attention to the crossmodal target. Moreover, the interaction between endogenous and exogenous orienting of attention is modulated by the modality between the cue and the target. © 2012 The Authors. Scandinavian Journal of Psychology © 2012 The Scandinavian Psychological Associations.

Growth and characterization of semi-insulating carbon-doped/undoped GaN multiple-layer buffer

International Nuclear Information System (INIS)

Kim, Dong-Seok; Won, Chul-Ho; Kang, Hee-Sung; Kim, Young-Jo; Kang, In Man; Lee, Jung-Hee; Kim, Yong Tae

2015-01-01

We have proposed a new semi-insulating GaN buffer layer, which consists of multiple carbon-doped and undoped GaN layer. The buffer layer showed sufficiently good semi-insulating characteristics, attributed to the depletion effect between the carbon-doped GaN and the undoped GaN layers, even though the thickness of the carbon-doped GaN layer in the periodic structure was designed to be very thin to minimize the total carbon incorporation into the buffer layer. The AlGaN/AlN/GaN heterostructure grown on the proposed buffer exhibited much better electrical and structural properties than that grown on the conventional thick carbon-doped semi-insulating GaN buffer layer, confirmed by Hall measurement, x-ray diffraction, and secondary ion mass spectrometry. The fabricated device also showed excellent buffer breakdown characteristics. (paper)

Generalized semi-Markovian dividend discount model: risk and return

OpenAIRE

D'Amico, Guglielmo

2016-01-01

The article presents a general discrete time dividend valuation model when the dividend growth rate is a general continuous variable. The main assumption is that the dividend growth rate follows a discrete time semi-Markov chain with measurable space. The paper furnishes sufficient conditions that assure finiteness of fundamental prices and risks and new equations that describe the first and second order price-dividend ratios. Approximation methods to solve equations are provided and some new...

Potential drop crack growth monitoring in high temperature biaxial fatigue tests

International Nuclear Information System (INIS)

Fitzgerald, B.P.; Krempl, E.

1993-01-01

The present work describes a procedure for monitoring crack growth in high temperature, biaxial, low cycle fatigue tests. The reversing DC potential drop equipment monitors smooth, tubular type 304 stainless steel specimens during fatigue testing. Electrical interference from an induction heater is filtered out by an analog filter and by using a long integration time. A Fourier smoothing algorithm and two spline interpolations process the large data set. The experimentally determined electrical potential drop is compared with the theoretical electrostatic potential that is found by solving Laplace's equation for an elliptical crack in a semi-infinite conducting medium. Since agreement between theory and experiment is good, the method can be used to measure crack growth to failure from the threshold of detectability

International spillovers, productivity growth and openness in Thailand

OpenAIRE

Diao, Xinshen; Rattsø, Jørn; Stokke, Hildegunn Ekroll

2002-01-01

The present paper addresses the growth process of Thailand... After all the theoretical growth modeling and the cross-country growth regressions, we suggest to go back to the country level to understand the growth dynamics. The focus is on endogenous productivity growth in transition towards long run balanced growth. Thailand has had remarkable economic growth of about 6-7% and well above world averages for 40-50 years, in transformation from a ‘rice economy' to industrialization. Interesting...

Reference Pricing with Endogenous or Exogenous Payment Limits: Impacts on Insurer and Consumer Spending.

Science.gov (United States)

Brown, Timothy T; Robinson, James C

2016-06-01

Reference pricing (RP) theories predict different outcomes when reference prices are fixed (exogenous) versus being a function of market prices (MPs) (endogenous). Exogenous RP results in MPs at both high-price and low-price firms converging towards the reference price from above and below, respectively. Endogenous RP results in MPs at both high-price and low-price firms decreasing, with low-price firms acting strategically to decrease the reference price in order to gain market share. We extend these models to a hospital context focusing on insurer and consumer payments. Under exogenous RP, insurer and consumer payments to low-price hospitals increase, and insurer payments to high-price hospitals decrease, but predictions regarding consumer payments are ambiguous for high-price hospitals. Under endogenous RP, insurer payments to high-price and low-price hospitals decrease, and consumer payments to low-price hospitals decrease, but predictions regarding consumer payments are ambiguous for high-price hospitals. We test these predictions with difference-in-differences specifications using 2008-2013 data on patients undergoing joint replacement. For 2 years following RP implementation, insurer payments to high-price and low-price hospitals moved downward, consistent with endogenous RP. However, when the reference price was not reset to account for changes in MPs, insurer payments to low-price hospitals reverted to pre-implementation levels, consistent with exogenous RP. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Are human endogenous retroviruses triggers of autoimmune diseases?

DEFF Research Database (Denmark)

Nexø, Bjørn A; Villesen, Palle; Nissen, Kari K

2016-01-01

factors. Viruses including human endogenous retroviruses have long been linked to the occurrence of autoimmunity, but never proven to be causative factors. Endogenous viruses are retroviral sequences embedded in the host germline DNA and transmitted vertically through successive generations in a Mendelian...... manner. In this study by means of genetic epidemiology, we have searched for the involvement of endogenous retroviruses in three selected autoimmune diseases: multiple sclerosis, type 1 diabetes mellitus, and rheumatoid arthritis. We found that at least one human endogenous retroviral locus...

Contagion risk in endogenous financial networks

International Nuclear Information System (INIS)

Li, Shouwei; Sui, Xin

2016-01-01

Highlights: • We propose an endogenous financial network model. • Endogenous networks include interbank networks, inter-firm networks and bank-firm networks. • We investigate contagion risk in endogenous financial networks. - Abstract: In this paper, we investigate contagion risk in an endogenous financial network, which is characterized by credit relationships connecting downstream and upstream firms, interbank credit relationships and credit relationships connecting firms and banks. The findings suggest that: increasing the number of potential lenders randomly selected can lead to an increase in the number of bank bankruptcies, while the number of firm bankruptcies presents a trend of increase after the decrease; after the intensity of choice parameter rises beyond a threshold, the number of bankruptcies in three sectors (downstream firms, upstream firms and banks) shows a relatively large margin of increase, and keeps at a relatively high level; there exists different trends for bankruptcies in different sectors with the change of the parameter of credits’ interest rates.

Endogenous price flexibility and optimal monetary policy

OpenAIRE

Ozge Senay; Alan Sutherland

2014-01-01

Much of the literature on optimal monetary policy uses models in which the degree of nominal price flexibility is exogenous. There are, however, good reasons to suppose that the degree of price flexibility adjusts endogenously to changes in monetary conditions. This article extends the standard new Keynesian model to incorporate an endogenous degree of price flexibility. The model shows that endogenizing the degree of price flexibility tends to shift optimal monetary policy towards complete i...

SemiBoost: boosting for semi-supervised learning.

Science.gov (United States)

Mallapragada, Pavan Kumar; Jin, Rong; Jain, Anil K; Liu, Yi

2009-11-01

Semi-supervised learning has attracted a significant amount of attention in pattern recognition and machine learning. Most previous studies have focused on designing special algorithms to effectively exploit the unlabeled data in conjunction with labeled data. Our goal is to improve the classification accuracy of any given supervised learning algorithm by using the available unlabeled examples. We call this as the Semi-supervised improvement problem, to distinguish the proposed approach from the existing approaches. We design a metasemi-supervised learning algorithm that wraps around the underlying supervised algorithm and improves its performance using unlabeled data. This problem is particularly important when we need to train a supervised learning algorithm with a limited number of labeled examples and a multitude of unlabeled examples. We present a boosting framework for semi-supervised learning, termed as SemiBoost. The key advantages of the proposed semi-supervised learning approach are: 1) performance improvement of any supervised learning algorithm with a multitude of unlabeled data, 2) efficient computation by the iterative boosting algorithm, and 3) exploiting both manifold and cluster assumption in training classification models. An empirical study on 16 different data sets and text categorization demonstrates that the proposed framework improves the performance of several commonly used supervised learning algorithms, given a large number of unlabeled examples. We also show that the performance of the proposed algorithm, SemiBoost, is comparable to the state-of-the-art semi-supervised learning algorithms.

The Naïve Murine Cornea as a Model System to Identify Novel Endogenous Regulators of Lymphangiogenesis: TRAIL and rtPA.

Science.gov (United States)

Regenfuß, Birgit; Dreisow, Marie-Luise; Hos, Deniz; Masli, Sharmila; Bock, Felix; Cursiefen, Claus

2015-06-01

In the murine cornea, which is an established model for analyzing pathologic lymphatic vessel growth, phenotypic heterogeneity of the endogenous lymphatic vessels in the limbus of the cornea was previously described. In this study, the cornea of BALB/c, C57BL/6, and FVB mice with different limbal lymphangiogenic phenotypes was analyzed to identify novel candidates potentially influencing lymphatic vessel growth. Pathway specific expression analysis of the cornea was performed to identify novel candidate genes. Corneal protein expression of the respective candidates was analyzed by fluorescent immunohistochemistry. The effect of the candidates on proliferation of human dermal lymphatic endothelial cells (HDLECs) was analyzed by BrdU proliferation ELISA. Thirteen genes were differentially regulated in corneas of mouse strains with more endogenous limbal lymphatic vessels (high-lymphangiogenic) (C57BL/6) compared to mouse strains with less endogenous limbal lymphatic vessels (low-lymphangiogenic) (BALB/c, FVB). Two candidates, Tumor necrosis factor (ligand) superfamily member 10 (Tnfsf10/Trail) and Plasminogen activator, tissue (Plat/tPA) were expressed in the cornea of BALB/c and C57BL/6 mice on the protein level. In vitro, Trail and recombinant tPA inhibited the proliferation of human dermal lymphatic endothelial cells. Molecular analysis of the naive cornea in mouse strains with different limbal lymphatic phenotypes is a valuable model to identify novel endogenous regulators of lymphangiogenesis.

Growth and relationship of live weight to body measurements in semi-domesticated reindeer (Rangifer tarandus tarandus L.

Directory of Open Access Journals (Sweden)

Mauri Nieminen

1990-09-01

Full Text Available Estimation of live weight from measurements of body dimensions is useful in many management activities with domestic animals. In present study live weight was measured from 2932 female and 1037 male semi-domesticated reindeer (Rangifer tarandus tarandus L. during different seasons in 1969-85. The age of reindeer varied between 1 day and 14 yrs. Back length (along back from second spinous process to base of tail and chest girth (just behind front legs were taken also from 1490 female and 510 male reindeer. The growth of reindeer from birth to adulthood was cumulative consisting of a rapid weight accretion during summers followed by a weight loss or stasis during winters. The mathematical analyses of the growth based on exponential solutions gave average values for growth of female and male reindeer. Body weight of females increased until the age of 4.5 yrs and that of males until the age of 5.5 yrs. During winter and spring body weight of hinds decreased 10 to 15 kg and that of stags 30 to 50 kg in different age groups. Significant linear regressions were found between live weight and back length (r = 0.809 and 0.892, live weight and chest girth (r = 0.860 and 0.872 and live weight and combined body measure (back length + chest girth (r = 0.877 and 0.941 and live weight and body volume (r = 0.905 and 0.954, respectively in female and male reindeer. Exponential regressions gave, however, the best estimations of live weight with combined body measure.

Jet substructure using semi-inclusive jet functions in SCET

International Nuclear Information System (INIS)

Kang, Zhong-Bo; Ringer, Felix; Vitev, Ivan

2016-01-01

We propose a new method to evaluate jet substructure observables in inclusive jet measurements, based upon semi-inclusive jet functions in the framework of Soft Collinear Effective Theory (SCET). As a first example, we consider the jet fragmentation function, where a hadron h is identified inside a fully reconstructed jet. We introduce a new semi-inclusive fragmenting jet function G_i"h(z=ω_J/ω,z_h=ω_h/ω_J,ω_J,R,μ), which depends on the jet radius R and the large light-cone momenta of the parton ‘i’ initiating the jet (ω), the jet (ω_J), and the hadron h (ω_h). The jet fragmentation function can then be expressed as a semi-inclusive observable, in the spirit of actual experimental measurements, rather than as an exclusive one. We demonstrate the consistency of the effective field theory treatment and standard perturbative QCD calculations of this observable at next-to-leading order (NLO). The renormalization group (RG) equation for the semi-inclusive fragmenting jet function G_i"h(z,z_h,ω_J,R,μ) are also derived and shown to follow exactly the usual timelike DGLAP evolution equations for fragmentation functions. The newly obtained RG equations can be used to perform the resummation of single logarithms of the jet radius parameter R up to next-to-leading logarithmic (NLL_R) accuracy. In combination with the fixed NLO calculation, we obtain NLO+NLL_R results for the hadron distribution inside the jet. We present numerical results for pp→(jet h)X in the new framework, and find excellent agreement with existing LHC experimental data.

Ablation of arginase II spares arginine and abolishes the arginine requirement for growth in male mice

Science.gov (United States)

Arginine is considered a semi-essential amino acid in many species, including humans, because under certain conditions its demand exceeds endogenous production. Arginine availability, however, is not only determined by its production, but also by its disposal. Manipulation of disposal pathways has t...

An Application of the Harmonic Oscillator Model to Verify Dunning’s Theory of the Economic Growth

Directory of Open Access Journals (Sweden)

Marcin Salamaga

2013-09-01

Full Text Available Analogies with mechanisms ruling the natural world have oft en been sought in the course of economic phenomena.Th is paper is also an attempt to combine the physical phenomenon of a harmonious oscillator withthe theory of economic growth by J. H. Dunning (1981. In his theory, Dunning distinguished stages of economicgrowth of countries that imply the dependency between the investment position of countries and theirGDP per capita, while the graph presenting this dependency reminds a trajectory of oscillating motion of adamped harmonic oscillator. Th is analogy has given inspiration to reinterpret the theory of economy on thegrounds of the mechanism of a physical model. In this paper, the harmonious oscillator motion equation wasadapted to the description of dependencies shown in the theory of economic growth by J. H. Dunning. Th emathematical solution of this equation is properly parameterised and parameters are estimated with the useof the Gauss-Newton algorithm. Th e main objective of this paper is to allocate a specifi c stage in the economicgrowth to each country on the basis of the values of parameter estimations of the proposed cyclical models ofchanges in the net investment indicator.

Molecular collision theory

CERN Document Server

Child, M S

2010-01-01

This high-level monograph offers an excellent introduction to the theory required for interpretation of an increasingly sophisticated range of molecular scattering experiments. There are five helpful appendixes dealing with continuum wavefunctions, Green's functions, semi-classical connection formulae, curve-crossing in the momentum representation, and elements of classical mechanics.The contents of this volume have been chosen to emphasize the quantum mechanical and semi-classical nature of collision events, with little attention given to purely classical behavior. The treatment is essentiall

Endogenous Pyrogen Physiology.

Science.gov (United States)

Beisel, William R.

1980-01-01

Discusses the physiology of endogenous pyrogen (EP), the fever-producing factor of cellular origin. Included are: its hormone-like role, its molecular nature, bioassay procedures, cellular production and mechanisms of EP action. (SA)

Study regarding the influence of the endogenous and exogenous factors on credit institution’s return on assets

OpenAIRE

Maria-Daciana RODEAN (COZMA); Nicolae BALTEŞ

2016-01-01

The goal of each credit institution is represented by profitability, an objective hardly to be achieved, taking into account that banks are practicing their usual activities within a banking system that hardly tries to recover. The main purpose of this research is to identify the existence of a dependency relationship between return on assets and endogenous factors (growth rate of the loan portfolios; the rate of growth of the provisions and solvency ratio) and the exogenous on...

Microscopic theory of dynamical subspace for large amplitude collective motion

International Nuclear Information System (INIS)

Sakata, Fumihiko; Marumori, Toshio; Ogura, Masanori.

1986-01-01

A full quantum theory appropriate for describing large amplitude collective motion is proposed by exploiting the basic idea of the semi-classical theory so far developed within the time-depedent Hartree-Fock theory. A central problem of the quantum theory is how to determine an optimal representation called a dynamical representation specific for the collective subspace where the large amplitude collective motion is replicated as precisely as possible. As an extension of the semi-classical theory where the concept of an approximate integral surface played an important role, the collective subspace is properly characterized by introducing a concept of an approximate invariant subspace of the Hamiltonian. (author)

A semi-discrete integrable multi-component coherently coupled nonlinear Schrödinger system

International Nuclear Information System (INIS)

Zhao, Hai-qiong; Yuan, Jinyun

2016-01-01

A new integrable semi-discrete version is proposed for the multi-component coherently coupled nonlinear Schrödinger equation. The integrability of the semi-discrete system is confirmed by existence of Lax pair and infinite number of conservation laws. With the aid of gauge transformations, explicit formulas for N -fold Darboux transformations are derived whereby some physically important solutions of the system are presented. Furthermore, the theory of the semi-discrete system including Lax pair, Darboux transformations, exact solutions and infinite number of conservation laws are shown for their continuous counterparts in the continuous limit. (paper)

Life History theory hypotheses on child growth: Potential implications for short and long-term child growth, development and health.

Science.gov (United States)

Said-Mohamed, Rihlat; Pettifor, John M; Norris, Shane A

2018-01-01

Life history theory integrates ecological, physiological, and molecular layers within an evolutionary framework to understand organisms' strategies to optimize survival and reproduction. Two life history hypotheses and their implications for child growth, development, and health (illustrated in the South African context) are reviewed here. One hypothesis suggests that there is an energy trade-off between linear growth and brain growth. Undernutrition in infancy and childhood may trigger adaptive physiological mechanisms prioritizing the brain at the expense of body growth. Another hypothesis is that the period from conception to infancy is a critical window of developmental plasticity of linear growth, the duration of which may vary between and within populations. The transition from infancy to childhood may mark the end of a critical window of opportunity for improving child growth. Both hypotheses emphasize the developmental plasticity of linear growth and the potential determinants of growth variability (including the role of parent-offspring conflict in maternal resources allocation). Implications of these hypotheses in populations with high burdens of undernutrition and infections are discussed. In South Africa, HIV/AIDS during pregnancy (associated with adverse birth outcomes, short duration of breastfeeding, and social consequences) may lead to a shortened window of developmental plasticity of growth. Furthermore, undernutrition and infectious diseases in children living in South Africa, a country undergoing a rapid nutrition transition, may have adverse consequences on individuals' cognitive abilities and risks of cardio-metabolic diseases. Studies are needed to identify physiological mechanisms underlying energy allocation between biological functions and their potential impacts on health. © 2017 Wiley Periodicals, Inc.

Noncommutative gauge theory for Poisson manifolds

Energy Technology Data Exchange (ETDEWEB)

Jurco, Branislav E-mail: jurco@mpim-bonn.mpg.de; Schupp, Peter E-mail: schupp@theorie.physik.uni-muenchen.de; Wess, Julius E-mail: wess@theorie.physik.uni-muenchen.de

2000-09-25

A noncommutative gauge theory is associated to every Abelian gauge theory on a Poisson manifold. The semi-classical and full quantum version of the map from the ordinary gauge theory to the noncommutative gauge theory (Seiberg-Witten map) is given explicitly to all orders for any Poisson manifold in the Abelian case. In the quantum case the construction is based on Kontsevich's formality theorem.

Noncommutative gauge theory for Poisson manifolds

International Nuclear Information System (INIS)

Jurco, Branislav; Schupp, Peter; Wess, Julius

2000-01-01

A noncommutative gauge theory is associated to every Abelian gauge theory on a Poisson manifold. The semi-classical and full quantum version of the map from the ordinary gauge theory to the noncommutative gauge theory (Seiberg-Witten map) is given explicitly to all orders for any Poisson manifold in the Abelian case. In the quantum case the construction is based on Kontsevich's formality theorem

Endogenously produced Indian Hedgehog regulates TGFβ-driven chondrogenesis of human bone marrow stromal/stem cells.

Science.gov (United States)

Handorf, Andrew M; Chamberlain, Connie S; Li, Wan-Ju

2015-04-15

Human bone marrow stromal/stem cells (hBMSCs) have an inherent tendency to undergo hypertrophy when induced into the chondrogenic lineage using transforming growth factor-beta 1 (TGFβ) in vitro, reminiscent of what occurs during endochondral ossification. Surprisingly, Indian Hedgehog (IHH) has received little attention for its role during hBMSC chondrogenesis despite being considered a master regulator of endochondral ossification. In this study, we investigated the role that endogenously produced IHH plays during hBMSC chondrogenesis. We began by analyzing the expression of IHH throughout differentiation using quantitative polymerase chain reaction and found that IHH expression was upregulated dramatically upon chondrogenic induction and peaked from days 9 to 12 of differentiation, which coincided with a concomitant increase in the expression of chondrogenesis- and hypertrophy-related markers, suggesting a potential role for endogenously produced IHH in driving hBMSC chondrogenesis. More importantly, pharmacological inhibition of Hedgehog signaling with cyclopamine or knockdown of IHH almost completely blocked TGFβ1-induced chondrogenesis in hBMSCs, demonstrating that endogenously produced IHH is necessary for hBMSC chondrogenesis. Furthermore, overexpression of IHH was sufficient to drive chondrogenic differentiation, even when TGFβ signaling was inhibited. Finally, stimulation with TGFβ1 induced a significant and sustained upregulation of IHH expression within 3 h that preceded an upregulation in all cartilage-related genes analyzed, and knockdown of IHH blocked the effects of TGFβ1 entirely, suggesting that the effects of TGFβ1 are being mediated through endogenously produced IHH. Together, our findings demonstrate that endogenously produced IHH is playing a critical role in regulating hBMSC chondrogenesis.

Modelling the effect of essential oil of betel leaf (Piper betle L.) on germination, growth, and apparent lag time of Penicillium expansum on semi-synthetic media.

Science.gov (United States)

Basak, Suradeep; Guha, Proshanta

2015-12-23

The current study aimed at characterizing the chemical components of betel leaf (Piper betle L. var. Tamluk Mitha) essential oil (BLEO) and modelling its effect on growth of Penicillium expansum on semi-synthetic medium. Gas chromatography-mass spectrophotometry (GC-MS) analysis of BLEO revealed the presence of different bioactive phenolic compounds in significant amounts. Among 46 different components identified, chavibetol (22.0%), estragole (15.8%), β-cubebene (13.6%), chavicol (11.8%), and caryophyllene (11.3%) were found to be the major compounds of BLEO. A disc diffusion and disc volatilization method were used to evaluate antifungal activity of the oil against a selected food spoilage mould. The logistic model was used to study the kinetics of spore germination. Prediction and validation of antifungal effect of BLEO was performed on semi-synthetic medium (apple juice agar) using predictive microbiological tools. The Baranyi and Roberts model was used to estimate maximum growth rate (μmax in mm/day) and apparent lag time (λ in days) of the mould. Secondary modelling was performed using a re-parameterized Monod-type equation based on cardinal values to study the effect of different BLEO concentration on estimated growth parameters. Emax (minimum concentration of oil at which mould growth was inhibited) and MIC (minimum inhibitory concentration of BLEO at which lag time is infinite) value of BLEO against P. expansum was estimated to be 0.56 and 0.74 μl/ml, respectively, which was found to be similar on potato dextrose agar (PDA) as well as apple juice agar (AJA) medium. The correlation between estimated growth parameters of the mould on both the media was obtained with satisfactory statistical indices (R(2) and RMSE). This study revealed inhibitory efficacy of BLEO on spore germination, mycelial growth and apparent lag time of P. expansum in a dose-dependent manner. Hence, BLEO has potential to be used as a natural food preservative. Copyright © 2015

Is really endogenous ghrelin a hunger signal in chickens? Association of GHSR SNPs with increase appetite, growth traits, expression and serum level of GHRL, and GH.

Science.gov (United States)

El-Magd, Mohammed Abu; Saleh, Ayman A; Abdel-Hamid, Tamer M; Saleh, Rasha M; Afifi, Mohammed A

2016-10-01

Chicken growth hormone secretagogue receptor (GHSR) is a receptor for ghrelin (GHRL), a peptide hormone produced by chicken proventriculus, which stimulates growth hormone (GH) release and food intake. The purpose of this study was to search for single nucleotide polymorphisms (SNPs) in exon 2 of GHSR gene and to analyze their effect on the appetite, growth traits and expression levels of GHSR, GHRL, and GH genes as well as serum levels of GH and GHRL in Mandara chicken. Two adjacent SNPs, A239G and G244A, were detected in exon 2 of GHSR gene. G244A SNP was non-synonymous mutation and led to replacement of lysine amino acid (aa) by arginine aa, while A239G SNP was synonymous mutation. The combined genotypes of A239G and G244A SNPs produced three haplotypes; GG/GG, GG/AG, AG/AG, which associated significantly (P4 to 16w. Chickens with the homozygous GG/GG haplotype showed higher growth performance than other chickens. The two SNPs were also correlated with mRNA levels of GHSR and GH (in pituitary gland), and GHRL (in proventriculus and hypothalamus) as well as with serum level of GH and GHRL. Also, chickens with GG/GG haplotype showed higher mRNA and serum levels. This is the first study to demonstrate that SNPs in GHSR can increase appetite, growth traits, expression and level of GHRL, suggesting a hunger signal role for endogenous GHRL. Copyright © 2016 Elsevier Inc. All rights reserved.

Influence of the growth process on some laws deduced from percolation theory

International Nuclear Information System (INIS)

Hachi, M.; Olivier, G.

1985-09-01

A brutal application of the percolation theory to some physical problems can lead to erroneous interpretation of the experimental results. Among these problems, the influence of the growth process on the percolation laws is studied. The behaviour of nsub(s)(t), the number of clusters of size s, at time t, is analyzed and linked to a macroscopic property of the system for a comparison to experimental laws. (author)

Inequality and growth in neo-Kaleckian and Cambridge growth theory

OpenAIRE

Palley, Thomas I.

2016-01-01

This paper examines the relationship between inequality and growth in the neo-Kaleckian and Cambridge growth models. The paper explores the channels whereby functional and personal income distribution impact growth. The growth - inequality relationship can be negative or positive, depending on the economy's characteristics. Contrary to widespread claims, inequality per se does not impact growth through macroeconomic channels. Instead, both growth and inequality are impacted by changes in the ...

Dynamic hysteresis of a uniaxial superparamagnet: Semi-adiabatic approximation

International Nuclear Information System (INIS)

Poperechny, I.S.; Raikher, Yu.L.; Stepanov, V.I.

2014-01-01

The semi-adiabatic theory of magnetic response of a uniaxial single-domain ferromagnetic particle is presented. The approach is developed in the context of the kinetic theory and allows for any orientation of the external field. Within this approximation, the dynamic magnetic hysteresis loops in an ac field are calculated. It is demonstrated that they very closely resemble those obtained by the full kinetic theory. The behavior of the effective coercive force is analyzed in detail, and for it a simple formula is proposed. This relation accounts not only for the temperature behavior of the coercive force, as the previous ones do, but also yields the dependence on the frequency and amplitude of the applied field

Endogenous Peer Effects: Fact or Fiction?

Science.gov (United States)

Yeung, Ryan; Nguyen-Hoang, Phuong

2016-01-01

The authors examine endogenous peer effects, which occur when a student's behavior or outcome is a function of the behavior or outcome of his or her peer group. Endogenous peer effects have important implications for educational policies such as busing, school choice and tracking. In this study, the authors quantitatively review the literature on…

Fully plastic solutions of semi-elliptical surface cracks

International Nuclear Information System (INIS)

Yagawa, Genki; Yoshimura, Shinobu; Kitajima, Yasumi; Ueda, Hiroyoshi.

1990-01-01

Nonlinear finite element analyses of semi-elliptical surface cracks are performed under the fully plastic condition. The power-law hardening materials and the deformation theory of plasticity are assumed. Either the penalty function method or the Uzawa's algorithm is utilized to treat the incompressibility of plastic strains. The local and global J-integral values are obtained using a virtual crack extension technique for plates and cylinders with semi-elliptical surface cracks subjected to uniform tensions. The fully plastic solutions for surface cracked plates are given in the form of polynominals with geometric parameters a/t, a/c and the strain hardening exponent (n). In addition, the effects of curvature on fully plastic solutions are discussed through the comparison between the results of plates and cylinders. (author)

A general theory of macrofinance: Towards a new paradigm

Directory of Open Access Journals (Sweden)

Chen Yulu

2017-01-01

Full Text Available The 2008 international financial crisis triggered retrospection on both theory and policy, reaching a macroeconomic consensus that the financial system plays an important role in the macro economy and macroeconomic theory must be restructured to incorporate endogenous financial factors. Reflecting on the inherent flaws of traditional mainstream economics, this paper puts forward a “macrofinance” proposition as a new paradigm for macro financial analysis. As a scientific methodology based on systematic logic, the major feature of the macrofinance framework is that we must analyze the financial system as a core part of a complete and endogenous analytical framework, instead of only focusing on the money or credit. The goal of “macrofinance” is to return to scientific economic methodologies by analyzing the inherent laws of modern financial systems to set up a comprehensive theoretical framework that unifies the financial sector with the real economy and combines theory and policy practice.

Poisson–Boltzmann theory of the charge-induced adsorption of semi-flexible polyelectrolytes

NARCIS (Netherlands)

Ubbink, J.; Khokhlov, A.R.

2004-01-01

A model is suggested for the structure of an adsorbed layer of a highly charged semi-flexible polyelectrolyte on a weakly charged surface of opposite charge sign. The adsorbed phase is thin, owing to the effective reversal of the charge sign of the surface upon adsorption, and ordered, owing to the

Frisch on Testing of Business Cycle Theories

NARCIS (Netherlands)

Boumans, M.

1995-01-01

An important identifying assumption for business cycle models is contained in the mathematical form of the model, which determines the nature of its possible movements. Tinbergen's and Frisch's original understanding of business cycle theories was that of a closed model, containing only endogenous

Therapeutic targeting strategies using endogenous cells and proteins.

Science.gov (United States)

Parayath, Neha N; Amiji, Mansoor M

2017-07-28

Targeted drug delivery has become extremely important in enhancing efficacy and reducing the toxicity of therapeutics in the treatment of various disease conditions. Current approaches include passive targeting, which relies on naturally occurring differences between healthy and diseased tissues, and active targeting, which utilizes various ligands that can recognize targets expressed preferentially at the diseased site. Clinical translation of these mechanisms faces many challenges including the immunogenic and toxic effects of these non-natural systems. Thus, use of endogenous targeting systems is increasingly gaining momentum. This review is focused on strategies for employing endogenous moieties, which could serve as safe and efficient carriers for targeted drug delivery. The first part of the review involves cells and cellular components as endogenous carriers for therapeutics in multiple disease states, while the second part discusses the use of endogenous plasma components as endogenous carriers. Further understanding of the biological tropism with cells and proteins and the newer generation of delivery strategies that exploits these endogenous approaches promises to provide better solutions for site-specific delivery and could further facilitate clinical translations. Copyright © 2017 Elsevier B.V. All rights reserved.

Interactive Effects of Endogenous and Exogenous Nutrition on Larval Development for Crown-Of-Thorns Starfish

Directory of Open Access Journals (Sweden)

Ciemon Frank Caballes

2017-03-01

Full Text Available Outbreaks of crown-of-thorns starfish are often attributed to step-changes in larval survivorship following anomalous increases in nutrients and food availability. However, larval growth and development is also influenced by the nutritional condition of spawning females, such that maternal provisioning may offset limitations imposed by limited access to exogenous sources of nutrients during the formative stages of larval development. This study examined the individual, additive, and interactive effects of endogenous (maternal diet: Acropora, Porites, mixed, and starved and exogenous (larval diet: high concentration at 104 cells·mL−1, low concentration at 103 algal cells·mL−1, and starved nutrition on the survival, growth, morphology, and development of larvae of the crown-of-thorns starfish. Female starfish on Acropora and mixed diet produced bigger oocytes compared to Porites-fed and starved treatments. Using oocyte size as a proxy for maternal provisioning, endogenous reserves in the oocyte had a strong influence on initial larval survival and development. This suggests that maternal reserves can delay the onset of obligate exogenous food acquisition and allow larvae to endure prolonged periods of poor environmental nutritive conditions or starvation. The influence of exogenous nutrition became more prominent in later stages, whereby none of the starved larvae reached the mid-to-late brachiolaria stage 16 days after the onset of the ability to feed. There was no significant difference in the survival, development, and competency of larvae between high and low food treatments. Under low algal food conditions, larvae compensate by increasing the length of ciliated feeding bands in relation to the maximum length and width, which improve food capture and feeding efficiency. However, the effects of endogenous nutrition persisted in the later developmental stages, as larvae from starved females were unable to develop larger feeding structures

Semi-doubled sigma models for five-branes

International Nuclear Information System (INIS)

Kimura, Tetsuji

2016-01-01

We study two-dimensional N=(2,2) gauge theory and its dualized system in terms of complex (linear) superfields and their alternatives. Although this technique itself is not new, we can obtain a new model, the so-called “semi-doubled” GLSM. Similar to doubled sigma model, this involves both the original and dual degrees of freedom simultaneously, whilst the latter only contribute to the system via topological interactions. Applying this to the N=(4,4) GLSM for H-monopoles, i.e., smeared NS5-branes, we obtain its T-dualized systems in quite an easy way. As a bonus, we also obtain the semi-doubled GLSM for an exotic 5_2"3-brane whose background is locally nongeometric. In the low energy limit, we construct the semi-doubled NLSM which also generates the conventional string worldsheet sigma models. In the case of the NLSM for 5_2"3-brane, however, we find that the Dirac monopole equation does not make sense any more because the physical information is absorbed into the divergent part via the smearing procedure. This is nothing but the signal which indicates that the nongeometric feature emerges in the considering model.

59 eyes with endogenous endophthalmitis

DEFF Research Database (Denmark)

Bjerrum, Søren Solborg; la Cour, Morten

2017-01-01

BACKGROUND: To study the epidemiology of patients with endogenous endophthalmitis in Denmark. MATERIAL AND METHODS: Retrospective and prospective case series of 59 eyes in patients with endogenous endophthalmitis in Denmark between 2000 and 2016. RESULTS: The age of the patients ranged from 28 to......, the visual outcome and the mortality of the patients. The epidemiology of the disease is very different in Scandinavia compared to Asia. The visual prognosis remains grave and the majority of the eyes lose useful vision....

Coherent states and covariant semi-spectral measures

International Nuclear Information System (INIS)

Scutaru, H.

1976-01-01

The close connection between Mackey's theory of imprimitivity systems and the so called generalized coherent states introduced by Perelomov is established. Coherent states give a covariant description of the ''localization'' of a quantum system in the phase space in a similar way as the imprimitivity systems give a covariant description of the localization of a quantum system in the configuration space. The observation that for any system of coherent states one can define a covariant semi-spectral measure made possible a rigurous formulation of this idea. A generalization of the notion of coherent states is given. Covariant semi-spectral measures associated with systems of coherent states are defined and characterized. Necessary and sufficient conditions for a unitary representation of a Lie group to be i) a subrepresentation of an induced one and ii) a representation with coherent states are given (author)

Jet substructure using semi-inclusive jet functions in SCET

Energy Technology Data Exchange (ETDEWEB)

Kang, Zhong-Bo [Theoretical Division, Los Alamos National Laboratory,Los Alamos, NM 87545 (United States); Department of Physics and Astronomy, University of California,Los Angeles, CA 90095 (United States); Ringer, Felix; Vitev, Ivan [Theoretical Division, Los Alamos National Laboratory,Los Alamos, NM 87545 (United States)

2016-11-25

We propose a new method to evaluate jet substructure observables in inclusive jet measurements, based upon semi-inclusive jet functions in the framework of Soft Collinear Effective Theory (SCET). As a first example, we consider the jet fragmentation function, where a hadron h is identified inside a fully reconstructed jet. We introduce a new semi-inclusive fragmenting jet function G{sub i}{sup h}(z=ω{sub J}/ω,z{sub h}=ω{sub h}/ω{sub J},ω{sub J},R,μ), which depends on the jet radius R and the large light-cone momenta of the parton ‘i’ initiating the jet (ω), the jet (ω{sub J}), and the hadron h (ω{sub h}). The jet fragmentation function can then be expressed as a semi-inclusive observable, in the spirit of actual experimental measurements, rather than as an exclusive one. We demonstrate the consistency of the effective field theory treatment and standard perturbative QCD calculations of this observable at next-to-leading order (NLO). The renormalization group (RG) equation for the semi-inclusive fragmenting jet function G{sub i}{sup h}(z,z{sub h},ω{sub J},R,μ) are also derived and shown to follow exactly the usual timelike DGLAP evolution equations for fragmentation functions. The newly obtained RG equations can be used to perform the resummation of single logarithms of the jet radius parameter R up to next-to-leading logarithmic (NLL{sub R}) accuracy. In combination with the fixed NLO calculation, we obtain NLO+NLL{sub R} results for the hadron distribution inside the jet. We present numerical results for pp→(jet h)X in the new framework, and find excellent agreement with existing LHC experimental data.

Independent effects of endogenous and exogenous attention in touch.

Science.gov (United States)

Jones, Alexander; Forster, Bettina

2013-12-01

Endogenous and exogenous attention in touch have typically been investigated separately. Here we use a double-cueing paradigm manipulating both types of orienting in each trial. Bilateral endogenous cues induced long-lasting facilitation of endogenous attention up to 2 s. However, the exogenous cue only elicited an effect at short intervals. Our results favour a supramodal account of attention and this study provides new insight into how endogenous and exogenous attention operates in the tactile modality.

Feature integration and spatial attention: common processes for endogenous and exogenous orienting.

Science.gov (United States)

Henderickx, David; Maetens, Kathleen; Soetens, Eric

2010-05-01

Briand (J Exp Psychol Hum Percept Perform 24:1243-1256, 1998) and Briand and Klein (J Exp Psychol Hum Percept Perform 13:228-241, 1987) demonstrated that spatial cueing effects are larger for detecting conjunction of features than for detecting simple features when spatial attention is oriented exogenously, and not when attention is oriented endogenously. Their results were interpreted as if only exogenous attention affects the posterior spatial attention system that performs the feature binding function attributed to spatial attention by Treisman's feature integration theory (FIT; 1980). In a series of 6 experiments, we attempted to replicate Briand's findings. Manipulations of distractor string size and symmetry of stimulus presentation left and right from fixation were implemented in Posner's cueing paradigm. The data indicate that both exogenous and endogenous cueing address the same attentional mechanism needed for feature binding. The results also limit the generalisability of Briand's proposal concerning the role of exogenous attention in feature integration. Furthermore, the importance to control the effect of unintended attentional capture in a cueing task is demonstrated.

Endogenous versus exogenous shocks in systems with memory

Science.gov (United States)

Sornette, D.; Helmstetter, A.

2003-02-01

Systems with long-range persistence and memory are shown to exhibit different precursory as well as recovery patterns in response to shocks of exogenous versus endogenous origins. By endogenous, we envision either fluctuations resulting from an underlying chaotic dynamics or from a stochastic forcing origin which may be external or be an effective coarse-grained description of the microscopic fluctuations. In this scenario, endogenous shocks result from a kind of constructive interference of accumulated fluctuations whose impacts survive longer than the large shocks themselves. As a consequence, the recovery after an endogenous shock is in general slower at early times and can be at long times either slower or faster than after an exogenous perturbation. This offers the tantalizing possibility of distinguishing between an endogenous versus exogenous cause of a given shock, even when there is no “smoking gun”. This could help in investigating the exogenous versus self-organized origins in problems such as the causes of major biological extinctions, of change of weather regimes and of the climate, in tracing the source of social upheaval and wars, and so on. Sornette et al., Volatility fingerprints of large stocks: endogenous versus exogenous, cond-mat/0204626 has already shown how this concept can be applied concretely to differentiate the effects on financial markets of the 11 September 2001 attack or of the coup against Gorbachev on 19 August 1991 (exogenous) from financial crashes such as October 1987 (endogenous).

Fiscal Policy in a Stochastic Model of Endogenous Growth

NARCIS (Netherlands)

Canton, E.J.F.

1997-01-01

It is nowadays widely believed that public schooling may contribute favourably to long-term economic growth. The income tax rates that are needed to finance government spending typically show an erratic time pattern. Such tax randomness could increase the intensity of the business cycle. Thus,

R&D Subsidies and the Surplus Appropriability Problem

DEFF Research Database (Denmark)

Sørensen, Anders

2005-01-01

or unwilling to use the level of spending required to implement the optimum policy. The argument is developed in a semi-endogenous growth model where the only distortion is monopoly pricing of intermediate goods.Keywords: R&D, policy instruments, welfare, market powerJEL: O38, O41...

Increasing the Capital Income Tax Leads to Faster Growth

NARCIS (Netherlands)

Uhlig, H.F.H.V.S.; Yanagawa, N.

1994-01-01

This paper shows that under rather mild conditions, higher capital income taxes lead to faster growth in an overlapping generations economy with endogenous growth. Government expenditures are financed with labor income taxes as well as capital income taxes. Since capital income accrues to the old,

Endogenous network states predict gain or loss of functions for genetic mutations in hepatocellular carcinoma.

Science.gov (United States)

Wang, Gaowei; Su, Hang; Yu, Helin; Yuan, Ruoshi; Zhu, Xiaomei; Ao, Ping

2016-02-01

Cancers have been typically characterized by genetic mutations. Patterns of such mutations have traditionally been analysed by posteriori statistical association approaches. One may ponder the possibility of a priori determination of any mutation regularity. Here by exploring biological processes implied in a mechanistic theory recently developed (the endogenous molecular-cellular network theory), we found that the features of genetic mutations in cancers may be predicted without any prior knowledge of mutation propensities. With hepatocellular carcinoma (HCC) as an example, we found that the normal hepatocyte and cancerous hepatocyte can be represented by robust stable states of one single endogenous network. These stable states, specified by distinct patterns of expressions or activities of proteins in the network, provide means to directly identify a set of most probable genetic mutations and their effects in HCC. As the key proteins and main interactions in the network are conserved through cell types in an organism, similar mutational features may also be found in other cancers. This analysis yielded straightforward and testable predictions on accumulated and preferred mutation spectra in normal tissue. The validation of predicted cancer state mutation patterns demonstrates the usefulness and potential of a causal dynamical framework to understand and predict genetic mutations in cancer. © 2016 The Author(s).

Time for Growth

DEFF Research Database (Denmark)

Boerner, Lars; Severgnini, Battista

This paper studies the impact of the early adoption of one of the most important high-technology machines in history, the public mechanical clock, on long-run growth in Europe. We avoid endogeneity by considering the relationship between the adoption of clocks with two sets of instruments: distance...... from the first adopters and the appearance of repeated solar eclipses. The latter instrument is motivated by the predecessor technologies of mechanical clocks, astronomic instruments that measured the course of heavenly bodies. We find significant growth rates between 1500 and 1700 in the range of 30...

THE CORRELATION BETWEEN RESEARCH AND DEVELOPMENT AND THE ECONOMIC GROWTH IN ROMANIA

Directory of Open Access Journals (Sweden)

Dragomir Laurentiu

2008-05-01

Full Text Available The increasing productivity of production factors, due to progresses in science and technology is today the engine of economic growth. The economic theory managed to endogenize the technical progress, first as a result of the unintended activities of firms, then as the result of profit driven behaviour of economic agents. In globalization the stock of knowledge becomes available also to developing countries and the production technologies and their employment are more democratic regarding the availability. For the developing countries it still remains the problem of financial resources and availability. Developing new technologies has a prohibitive costs, at least until the moment in which large scale production allows for the reduction of costs. Long term economic growth will depend on the creation of global technology stock, including the leverage effect of sustained RxD. In this paper we will approach the progress of Romania in the area of knowledge base economy, especially regarding the policies in the RxD sector.

Stimulating endogenous cardiac regeneration

Directory of Open Access Journals (Sweden)

Amanda eFinan

2015-09-01

Full Text Available The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration,a combination of these approaches couldameliorate the overall repair process to incorporate the participation ofmultiple cell players.

Methylated DNA Immunoprecipitation Analysis of Mammalian Endogenous Retroviruses.

Science.gov (United States)

Rebollo, Rita; Mager, Dixie L

2016-01-01

Endogenous retroviruses are repetitive sequences found abundantly in mammalian genomes which are capable of modulating host gene expression. Nevertheless, most endogenous retrovirus copies are under tight epigenetic control via histone-repressive modifications and DNA methylation. Here we describe a common method used in our laboratory to detect, quantify, and compare mammalian endogenous retrovirus DNA methylation. More specifically we describe methylated DNA immunoprecipitation (MeDIP) followed by quantitative PCR.

International Environmental Agreements with Endogenous or Exogenous Risk

OpenAIRE

Fuhai Hong; Larry Karp

2014-01-01

We examine the effect of endogenous and exogenous risk on the equilibrium (expected) membership of an International Environmental Agreement when countries are risk averse. Endogenous risk arises when countries use mixed rather than pure strategies at the participation game, and exogenous risk arises from the inherent uncertainty about the costs and benefits of increased abate- ment. Under endogenous risk, an increase in risk aversion increases expected participation. Under exogenous risk and ...

The Conditions under which Growth-Fostering Relationships Promote Resilience and Alleviate Psychological Distress among Sexual Minorities: Applications of Relational Cultural Theory

Science.gov (United States)

Mereish, Ethan H.; Poteat, V. Paul

2015-01-01

Relational cultural theory posits that resilience and psychological growth are rooted in relational connections and are facilitated through growth-fostering relationships. Framed within this theory, the current study examined the associations between growth-fostering relationships (i.e., relationships characterized by authenticity and mutuality) with a close friend and psychological distress among sexual minorities. More specifically, we tested the moderating effects of individuals’ internalized homophobia and their friend’s sexual orientation on the associations between growth-fostering relationship with their close friend and level of psychological distress. A sample of sexual minorities (N = 661) were recruited online and completed a questionnaire. The 3-way interaction between (a) growth-fostering relationship with a close friend, (b) the close friend’s sexual orientation, and (c) internalized homophobia was significant in predicting psychological distress. Among participants with low levels of internalized homophobia, a stronger growth-fostering relationship with a close heterosexual or LGBT friend was associated with less psychological distress. Among participants with high levels of internalized homophobia, a stronger growth-fostering relationship with a close LGBT friend was associated with less psychological distress but not with a heterosexual friend. Our results demonstrate that growth-fostering relationships may be associated with less psychological distress but under specific conditions. These findings illuminate a potential mechanism for sexual minorities’ resilience and provide support for relational cultural theory. Understanding resilience factors among sexual minorities is critical for culturally sensitive and affirmative clinical practice and future research. PMID:26380836

Adaptation at Scale in Semi-Arid Regions | IDRC - International ...

International Development Research Centre (IDRC) Digital Library (Canada)

People living in Africa and South Asia's semi-arid regions face challenges that hinder their economic growth and development. This project seeks to find proactive, longer-term approaches to climate change adaptation in these vulnerable regions, while helping locals manage existing risks. Short-term focus must shift. So far ...

Poisson-Boltzmann theory of the charge-induced adsorption of semi-flexible polyelectrolytes.

Science.gov (United States)

Ubbink, Job; Khokhlov, Alexei R

2004-03-15

A model is suggested for the structure of an adsorbed layer of a highly charged semi-flexible polyelectrolyte on a weakly charged surface of opposite charge sign. The adsorbed phase is thin, owing to the effective reversal of the charge sign of the surface upon adsorption, and ordered, owing to the high surface density of polyelectrolyte strands caused by the generally strong binding between polyelectrolyte and surface. The Poisson-Boltzmann equation for the electrostatic interaction between the array of adsorbed polyelectrolytes and the charged surface is solved for a cylindrical geometry, both numerically, using a finite element method, and analytically within the weak curvature limit under the assumption of excess monovalent salt. For small separations, repulsive surface polarization and counterion osmotic pressure effects dominate over the electrostatic attraction and the resulting electrostatic interaction curve shows a minimum at nonzero separations on the Angstrom scale. The equilibrium density of the adsorbed phase is obtained by minimizing the total free energy under the condition of equality of chemical potential and osmotic pressure of the polyelectrolyte in solution and in the adsorbed phase. For a wide range of ionic conditions and charge densities of the charged surface, the interstrand separation as predicted by the Poisson-Boltzmann model and the analytical theory closely agree. For low to moderate charge densities of the adsorbing surface, the interstrand spacing decreases as a function of the charge density of the charged surface. Above about 0.1 M excess monovalent salt, it is only weakly dependent on the ionic strength. At high charge densities of the adsorbing surface, the interstrand spacing increases with increasing ionic strength, in line with the experiments by Fang and Yang [J. Phys. Chem. B 101, 441 (1997)]. (c) 2004 American Institute of Physics.

Design and Test of Semi-Active Vibration-Reducing System for Lathe

Directory of Open Access Journals (Sweden)

Hongsheng Hu

2014-09-01

Full Text Available In this paper, its theory design, analysis and test system of semi-active vibration controlling system used for precision machine have been done. Firstly, lathe bed and spindle entity were modeled by using UG software; Then modes of the machine bed and the key components of spindle were obtained by using ANSYS software; Finally, harmonic response analysis of lathe spindle under complex load was acquired, which provided a basis of MR damper’s structure optimization design for a certain type of precision machine. In order to prove its effectives, a prototype semi-active vibration controlling lathe with MR damper was developed. Tests have been done, and comparison results between passive vibration isolation equipment and semi-active vibration controlling equipment proved its good performances of MR damper.

Impulse or propagation? How the tides turned in Business Cycle Theory

NARCIS (Netherlands)

Reijnders, J.P.G.

This paper contains a short history of business cycle theory. It is argued that in the course of time the emphasis shifted from a mainly exogenous to a mainly endogenous explanation of the cycle. After the integration of the two approaches in the so-called impulse and propagation theory, the balance

Interscan variation of semi-automated volumetry of subsolid pulmonary nodules

International Nuclear Information System (INIS)

Scholten, Ernst T.; Jong, Pim A. de; Willemink, Martin J.; Mali, Willem P.T.M.; Gietema, Hester A.; Jacobs, Colin; Riel, Sarah van; Ginneken, Bram van; Vliegenthart, Rozemarijn; Oudkerk, Matthijs; Koning, Harry J. de; Horeweg, Nanda; Prokop, Mathias

2015-01-01

We aimed to test the interscan variation of semi-automatic volumetry of subsolid nodules (SSNs), as growth evaluation is important for SSN management. From a lung cancer screening trial all SSNs that were stable over at least 3 months were included (N = 44). SSNs were quantified on the baseline CT by two observers using semi-automatic volumetry software for effective diameter, volume, and mass. One observer also measured the SSNs on the second CT 3 months later. Interscan variation was evaluated using Bland-Altman plots. Observer agreement was calculated as intraclass correlation coefficient (ICC). Data are presented as mean (± standard deviation) or median and interquartile range (IQR). A Mann-Whitney U test was used for the analysis of the influence of adjustments on the measurements. Semi-automatic measurements were feasible in all 44 SSNs. The interscan limits of agreement ranged from -12.0 % to 9.7 % for diameter, -35.4 % to 28.6 % for volume and -27.6 % to 30.8 % for mass. Agreement between observers was good with intraclass correlation coefficients of 0.978, 0.957, and 0.968 for diameter, volume, and mass, respectively. Our data suggest that when using our software an increase in mass of 30 % can be regarded as significant growth. (orig.)

Interscan variation of semi-automated volumetry of subsolid pulmonary nodules

Energy Technology Data Exchange (ETDEWEB)

Scholten, Ernst T. [University Medical Center, Department of Radiology, Utrecht (Netherlands); Kennemer Gasthuis, Department of Radiology, Haarlem (Netherlands); Jong, Pim A. de; Willemink, Martin J.; Mali, Willem P.T.M.; Gietema, Hester A. [University Medical Center, Department of Radiology, Utrecht (Netherlands); Jacobs, Colin; Riel, Sarah van [Radboud University Medical Center, Diagnostic Image Analysis Group, Nijmegen (Netherlands); Ginneken, Bram van [Radboud University Medical Center, Diagnostic Image Analysis Group, Nijmegen (Netherlands); Fraunhofer MEVIS, Bremen (Germany); Vliegenthart, Rozemarijn [University of Groningen, University Medical Center Groningen, Department of Radiology, Groningen (Netherlands); University of Groningen, University Medical Centre Groningen, Center for Medical Imaging-North East Netherlands, Groningen (Netherlands); Oudkerk, Matthijs [University of Groningen, University Medical Centre Groningen, Center for Medical Imaging-North East Netherlands, Groningen (Netherlands); Koning, Harry J. de [Erasmus Medical Center, Department of Public Health, Rotterdam (Netherlands); Horeweg, Nanda [Erasmus Medical Center, Department of Public Health, Rotterdam (Netherlands); Erasmus Medical Center, Department of Pulmonology, Rotterdam (Netherlands); Prokop, Mathias [Radboud University Medical Center, Department of Radiology, Nijmegen (Netherlands)

2015-04-01

We aimed to test the interscan variation of semi-automatic volumetry of subsolid nodules (SSNs), as growth evaluation is important for SSN management. From a lung cancer screening trial all SSNs that were stable over at least 3 months were included (N = 44). SSNs were quantified on the baseline CT by two observers using semi-automatic volumetry software for effective diameter, volume, and mass. One observer also measured the SSNs on the second CT 3 months later. Interscan variation was evaluated using Bland-Altman plots. Observer agreement was calculated as intraclass correlation coefficient (ICC). Data are presented as mean (± standard deviation) or median and interquartile range (IQR). A Mann-Whitney U test was used for the analysis of the influence of adjustments on the measurements. Semi-automatic measurements were feasible in all 44 SSNs. The interscan limits of agreement ranged from -12.0 % to 9.7 % for diameter, -35.4 % to 28.6 % for volume and -27.6 % to 30.8 % for mass. Agreement between observers was good with intraclass correlation coefficients of 0.978, 0.957, and 0.968 for diameter, volume, and mass, respectively. Our data suggest that when using our software an increase in mass of 30 % can be regarded as significant growth. (orig.)

Importance of Endogenous Fibrinolysis in Platelet Thrombus Formation.

Science.gov (United States)

Gue, Ying X; Gorog, Diana A

2017-08-25

The processes of thrombosis and coagulation are finely regulated by endogenous fibrinolysis maintaining healthy equilibrium. When the balance is altered in favour of platelet activation and/or coagulation, or if endogenous fibrinolysis becomes less efficient, pathological thrombosis can occur. Arterial thrombosis remains a major cause of morbidity and mortality in the world despite advances in medical therapies. The role endogenous fibrinolysis in the pathogenesis of arterial thrombosis has gained increasing attention in recent years as it presents novel ways to prevent and treat existing diseases. In this review article, we discuss the role of endogenous fibrinolysis in platelet thrombus formation, methods of measurement of fibrinolytic activity, its role in predicting cardiovascular diseases and clinical outcomes and future directions.

A systematic effective operator analysis of semi-annihilating dark matter

International Nuclear Information System (INIS)

Cai, Yi; Spray, Andrew

2017-01-01

Semi-annihilation is a generic feature of dark matter theories stabilized by symmetries larger than a ℤ 2 . It contributes to thermal freeze out, but is irrelevant for direct and collider searches. This allows semi-annihilating dark matter to avoid those limits in a natural way. We use an effective operator approach to make the first model-independent study of the associated phenomenology. We enumerate all possible operators that contribute to 2→2 semi-annihilation up to dimension 6, plus leading terms at dimension 7. We find that when the only light states charged under the dark symmetry are dark matter, the model space is highly constrained. Only fifteen operators exist, and just two for single-component dark sectors. If there can be additional light, unstable “dark partner” states the possible phenomenology greatly increases, at the cost of additional model dependence in the dark partner decay modes. We also derive the irreducible constraints on models with single-component dark matter from cosmic ray searches and astrophysical observations. We find that for semi-annihilation to electrons and light quarks, the thermal relic cross sections can be excluded for dark matter masses up to 100 GeV. However, significant model space for semi-annihilating dark matter remains.

Comparison of theory and experiment for elastic-plastic plane-strain crack growth. [AISI 4140 steel

Energy Technology Data Exchange (ETDEWEB)

Hermann, L.; Rice, J.R.

1980-08-01

Recent theoretical results on elastic-plastic plane-strain crack growth are reviewed and experimental results for crack growth in a 4140 steel are discussed in terms of the theoretical concepts. The theory is based on a recent asymptotic analysis of crack surface opening and strain distributions at a quasistatically advancing crack tip in an ideally plastic solid. The analysis is incomplete in that some of the parameters which appear in it are known only approximately, especially at large-scale yielding. Nevertheless, it is sufficient for the derivation of a relation between the imposed loading and amount of crack growth prior to general yielding, based on the assumption that a geometrically similar near-tip crack profile is maintained during growth. The resulting predictions for the variation of J with crack growth are found to fit well to the experimental results obtained on deeply cracked compact specimens.

Bilateral endogenous Fusarium solani endophthalmitis in a liver-transplanted patient

DEFF Research Database (Denmark)

Jørgensen, Jesper Skovlund; Prause, Jan Ulrik; Kiilgaard, Jens Folke

2014-01-01

Endogenous Fusarium endophthalmitis is a rare disease predominantly described in immunocompromised patients often due to leukemia. We report a case of bilateral endogenous Fusarium solani endophthalmitis in a liver-transplanted patient.......Endogenous Fusarium endophthalmitis is a rare disease predominantly described in immunocompromised patients often due to leukemia. We report a case of bilateral endogenous Fusarium solani endophthalmitis in a liver-transplanted patient....

Feeding Releases Endogenous Opioids in Humans.

Science.gov (United States)

Tuulari, Jetro J; Tuominen, Lauri; de Boer, Femke E; Hirvonen, Jussi; Helin, Semi; Nuutila, Pirjo; Nummenmaa, Lauri

2017-08-23

The endogenous opioid system supports a multitude of functions related to appetitive behavior in humans and animals, and it has been proposed to govern hedonic aspects of feeding thus contributing to the development of obesity. Here we used positron emission tomography to investigate whether feeding results in hedonia-dependent endogenous opioid release in humans. Ten healthy males were recruited for the study. They were scanned with the μ-opioid-specific ligand [ 11 C]carfentanil three times, as follows: after a palatable meal, a nonpalatable meal, and after an overnight fast. Subjective mood, satiety, and circulating hormone levels were measured. Feeding induced significant endogenous opioid release throughout the brain. This response was more pronounced following a nonpalatable meal versus a palatable meal, and independent of the subjective hedonic responses to feeding. We conclude that feeding consistently triggers cerebral opioid release even in the absence of subjective pleasure associated with feeding, suggesting that metabolic and homeostatic rather than exclusively hedonic responses play a role in the feeding-triggered cerebral opioid release. SIGNIFICANCE STATEMENT The endogenous opioid system supports both hedonic and homeostatic functions. It has been proposed that overeating and concomitant opioid release could downregulate opioid receptors and promote the development of obesity. However, it remains unresolved whether feeding leads to endogenous opioid release in humans. We used in vivo positron emission tomography to test whether feeding triggers cerebral opioid release and whether this response is associated with pleasurable sensations. We scanned volunteers using the μ-opioid receptor-specific radioligand [ 11 C]carfentanil three times, as follows: after an overnight fast, after consuming a palatable meal, and after consuming a nonpalatable meal. Feeding led to significant endogenous opioid release, and this occurred also in the absence of feeding

Effect of cryptosporidial and giardial diarrhoea on social maturity, intelligence and physical growth in children in a semi-urban slum in south India.

Science.gov (United States)

Ajjampur, S S R; Koshy, B; Venkataramani, M; Sarkar, R; Joseph, A A; Jacob, K S; Ward, H; Kang, G

2011-01-01

Early childhood diarrhoea is a major cause of infant morbidity and mortality in developing countries. Recurrent and persistent diarrhoea affect growth and cognition in children as young as 6 years. To evaluate the effect of early childhood cryptosporidial and giardial diarrhoea on growth and development in children in a semi-urban slum in India. This is the first report of such assessment at 3 years of age. This study was undertaken on 116 children who were part of an ongoing birth cohort study (n=452) of rotaviral and cryptosporidial diarrhoea between June and December 2005. Social quotients (SQ) assessed by the Vineland Social Maturity Scale, intelligence quotients (IQ) assessed by the Seguin Form Board Test, physical growth parameters and sociodemographic data in 84 children with a history of cryptosporidial or giardial diarrhoea were compared with those of 32 without diarrhoea. Children with a past history of giardial diarrhoea showed a trend towards lower SQ (p=0.09) and had significantly lower IQ (p=0.04) and increased wasting (p=0.04). Cryptosporidial diarrhoea was not associated with poor IQ, SQ or physical growth. This study demonstrates the long-term effect of protozoan diarrhoea, especially that caused by giardia, on both intelligence and physical growth in Indian children as early as 3 years of age and re-inforces the need for early detection and prevention of early childhood protozoan diarrhoea.

Process of endogenous homeostatic characteristics decline in two suproopganismal biosystems from the standpoint of parametabolistic theory of senescence.

Science.gov (United States)

Makrushin, A V; Aladin, N V

2016-01-01

Endogenous decline in homeostatic characteristics of supraorganismal level systems is similar to individual senescence. Similarity is in the fact that this decline as individual senescence is called by negative consequences from specialization of elements the system consists. In systems of supraorganismal level these effects are analogues of parametabolic reactions of senescence individuals.

Proliferation of murine midbrain neural stem cells depends upon an endogenous sonic hedgehog (Shh) source.

Science.gov (United States)

Martínez, Constanza; Cornejo, Víctor Hugo; Lois, Pablo; Ellis, Tammy; Solis, Natalia P; Wainwright, Brandon J; Palma, Verónica

2013-01-01

The Sonic Hedgehog (Shh) pathway is responsible for critical patterning events early in development and for regulating the delicate balance between proliferation and differentiation in the developing and adult vertebrate brain. Currently, our knowledge of the potential role of Shh in regulating neural stem cells (NSC) is largely derived from analyses of the mammalian forebrain, but for dorsal midbrain development it is mostly unknown. For a detailed understanding of the role of Shh pathway for midbrain development in vivo, we took advantage of mouse embryos with cell autonomously activated Hedgehog (Hh) signaling in a conditional Patched 1 (Ptc1) mutant mouse model. This animal model shows an extensive embryonic tectal hypertrophy as a result of Hh pathway activation. In order to reveal the cellular and molecular origin of this in vivo phenotype, we established a novel culture system to evaluate neurospheres (nsps) viability, proliferation and differentiation. By recreating the three-dimensional (3-D) microenvironment we highlight the pivotal role of endogenous Shh in maintaining the stem cell potential of tectal radial glial cells (RGC) and progenitors by modulating their Ptc1 expression. We demonstrate that during late embryogenesis Shh enhances proliferation of NSC, whereas blockage of endogenous Shh signaling using cyclopamine, a potent Hh pathway inhibitor, produces the opposite effect. We propose that canonical Shh signaling plays a central role in the control of NSC behavior in the developing dorsal midbrain by acting as a niche factor by partially mediating the response of NSC to epidermal growth factor (EGF) and fibroblast growth factor (FGF) signaling. We conclude that endogenous Shh signaling is a critical mechanism regulating the proliferation of stem cell lineages in the embryonic dorsal tissue.

The Solow residual as a black box: attemps at integrating business cycle and growth theories

NARCIS (Netherlands)

Mata, T.; Louçã, F.

2009-01-01

Robert Solow's "Technical Change and the Aggregate Production Function" (1957) has had an enduring influence on macroeconomics. In this article, we examine the history of fluctuations in growth theory through the story of the "Solow residual" as a "black box." We show that after Solow's seminal

Identification of BC005512 as a DNA damage responsive murine endogenous retrovirus of GLN family involved in cell growth regulation.

Directory of Open Access Journals (Sweden)

Yuanfeng Wu

Full Text Available Genotoxicity assessment is of great significance in drug safety evaluation, and microarray is a useful tool widely used to identify genotoxic stress responsive genes. In the present work, by using oligonucleotide microarray in an in vivo model, we identified an unknown gene BC005512 (abbreviated as BC, official full name: cDNA sequence BC005512, whose expression in mouse liver was specifically induced by seven well-known genotoxins (GTXs, but not by non-genotoxins (NGTXs. Bioinformatics revealed that BC was a member of the GLN family of murine endogenous retrovirus (ERV. However, the relationship to genotoxicity and the cellular function of GLN are largely unknown. Using NIH/3T3 cells as an in vitro model system and quantitative real-time PCR, BC expression was specifically induced by another seven GTXs, covering diverse genotoxicity mechanisms. Additionally, dose-response and linear regression analysis showed that expression level of BC in NIH/3T3 cells strongly correlated with DNA damage, measured using the alkaline comet assay,. While in p53 deficient L5178Y cells, GTXs could not induce BC expression. Further functional studies using RNA interference revealed that down-regulation of BC expression induced G1/S phase arrest, inhibited cell proliferation and thus suppressed cell growth in NIH/3T3 cells. Together, our results provide the first evidence that BC005512, a member from GLN family of murine ERV, was responsive to DNA damage and involved in cell growth regulation. These findings could be of great value in genotoxicity predictions and contribute to a deeper understanding of GLN biological functions.

Post-weaning growth of endemic Iberian wild rabbit subspecies, Oryctolagus cuniculus algirus, kept in a semi-extensive enclosure : implications for management and conservation

Directory of Open Access Journals (Sweden)

A. Ferreira

2014-06-01

Full Text Available Little is known about the endemic Iberian wild rabbit subspecies, Oryctolagus cuniculus algirus, despite its importance in Mediterranean ecosystems. An individual’s physical condition is of undisputed importance when evaluating the quality of habitats or restocking enclosures to assess the corresponding population status. We analysed post-weaning body weight and growth of 351 individuals of the endemic Oryctolagus cuniculus algirus subspecies under semi-natural conditions in a breeding enclosure in central Portugal. From these data, we described and estimated growth rates for juvenile and adult stages, and 3 sigmoidal growth models were developed. Body weight showed a linear growth of 0.00765 kg/d until 0.6 kg, whereafter it began to decrease steeply until 1 kg (<0.005 kg/d between 0.6 and 0.7 kg, <0.003 kg/d between 0.7 and 0.9 kg, and <0.001 kg/d then on. An age prediction linear growth equation was estimated for individuals up to 0.6 kg. The von Bertalanffy model best described the observed body weight growth. Juvenile body weight growth of Oryctolagus cuniculus algirus is lower than that of the widespread Oryctolagus cuniculus cuniculus. Our data revealed that Oryctolagus cuniculus algirus seems to be smaller, grows less and for less time than Oryctolagus cuniculus cuniculus, according to the literature. Body weight of the studied individuals seems to be more similar to free-living than to cage-bred individuals, according to the literature. These results should provide important indicators to assist managers and conservationists in accessing habitat quality for wild rabbit populations.

Elastic Labour Supply and Home Production in a Monetary Growth Model

Directory of Open Access Journals (Sweden)

Wei-Bin Zhang

2011-10-01

Full Text Available This study constructs a monetary gender growth model with capital accumulation and endogenous labour supply. The real aspects of the model are based on the neoclassical growth theory and monetary aspects of the model are based on the cash-in-advance (CIA approach. We show that the dynamics of the economy can be described by 2-dimensional differential equations. We simulate equilibrium and motion of the economy with specified monetary policies, household preference and technology. As the monetary economic system is unstable, the economy may either experience unlimited growth or economic crisis. We also study effects of changes in some parameters on the economic equilibrium. For instance, as the woman raises her propensity to stay at home, the capital intensity is not affected, which results in that the wage rates, the rate and output level per unit of labour input are not affected. Nevertheless, the man increases his work time and the woman reduces her work time, resulting in the fall of the labour supply. The money holing, durable goods used at home and consumption level per household are reduced; also the total wealth, total capital inputs, total durable goods and total output levels are reduced.

Economic growth factors system: theoretical and methodological aspect

OpenAIRE

H.Ya. Hlukha

2014-01-01

The aim of the article. The main objective of the article is to create theoretical grounds to build the system of economic growth factors, to modernize their classification, to define exogenous and endogenous factors, to analyze them within the state economic policy structure. The results of the analysis. The article focuses on economic growth factors theoretical studies: - economic growth factors classification characteristics have been highlighted; - various approaches to determine...

Applying Endogenous Knowledge in the African Context ...

African Journals Online (AJOL)

The question presented in this article is how to improve the dispute resolution competence of practitioners in Africa. The response offered involves enhancing the endogenous knowledge of a dispute and how to resolve it. This requires not only an understanding of what endogenous knowledge is, but also an alignment of ...

The individual life-cycle, annuity market imperfections and economic growth

NARCIS (Netherlands)

Heijdra, Ben J.; Mierau, Jochen O.

We study the effects of an annuity market imperfection on individual agents' life-cycle decisions and on the macroeconomic growth rate in an overlapping generations model with single-sector endogenous growth. Our model features both age-dependent mortality and labour productivity. We model imperfect

A Theory of Tolerance

OpenAIRE

Corneo, Giacomo; Jeanne, Olivier

2006-01-01

We develop an economic theory of tolerance where styles of behaviour are invested with symbolic value. Value systems are endogenous and taught by parents to their children. In conjunction with actual behaviour, value systems determine the esteem enjoyed by individuals. Intolerant individuals have all symbolic value invested in a single style of behaviour, whereas tolerant people have diversified values. The proposed model identifies a link between the unpredictability of children's lifestyles...

Explaining Cigarette Smoking: An Endogenous-Exogenous Analysis.

Science.gov (United States)

McKillip, Jack

Kruglanski's endogenous-exogenous partition, when applied to reasons given by smokers for smoking cigarettes, distinguishes two types of actions: (1) endogenous reasons implying that the behavior of consuming the cigarette is the goal of the action and the actor is positive toward the behavior, and (2) exogenous reasons implying that the behavior…

Natural disasters impacting a macroeconomic model with endogenous dynamics

International Nuclear Information System (INIS)

Hallegatte, Stephane; Ghil, Michael

2008-01-01

We investigate the macroeconomic response to natural disasters by using an endogenous business cycle (EnBC) model in which cyclical behavior arises from the investment-profit instability. Our model exhibits a larger response to natural disasters during expansions than during recessions. This apparently paradoxical result can be traced to the disasters amplifying pre-existing disequilibria during expansions, while the existence of unused resources during recessions damps the exogenous shocks. It thus appears that high-growth periods are also highly vulnerable to supply-side shocks. In our EnBC model, the average production loss due to a set of disasters distributed at random in time is highly sensitive to the dynamical characteristics of the impacted economy. Larger economic flexibility allows for a more efficient and rapid response to supply-side shocks and reduces production losses. On the other hand, too high a flexibility can lead to vulnerability phases that cause average production losses to soar. These results raise questions about the assessment of climate change damages or natural disaster losses that are based purely on long-term growth models. (author)

Endogenous opiates and behavior: 2014.

Science.gov (United States)

Bodnar, Richard J

2016-01-01

This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants). This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular

Field-based experimental water footprint study of sunflower growth in a semi-arid region of China.

Science.gov (United States)

Qin, Lijie; Jin, Yinghua; Duan, Peili; He, Hongshi

2016-07-01

Field-scale changes in the water footprint during crop growth play an important role in formulating sustainable water utilisation strategies. This study aimed to explore field-scale variation in the water footprint of growing sunflowers in the western Jilin Province, China, during a 3-year field experiment. The goals of this study were to (1) determine the components of the 'blue' and 'green' water footprints for sunflowers sown with water, and (2) analyse variations in water footprints and soil water balance under different combinations of temperature and precipitation. Specific actions could be adopted to maintain sustainable agricultural water utilisation in the semi-arid region based on this study. The green, blue, and grey water footprints accounted for 93.7-94.7%, 0.4-0.5%, and 4.9-5.8%, respectively, of the water footprint of growing sunflowers. The green water footprint for effective precipitation during the growing season accounted for 58.8% in a normal drought year but 48.2% in an extreme drought year. When the effective precipitation during the growing season could not meet the green water use, a moisture deficit arose. This increase in the moisture deficit can have a significant impact on soil water balance. Green water was the primary water source for sunflower growth in the study area, where a scarcity of irrigation water during sunflower growth damaged the soil water balance, particularly in years with continuous drought. The combination of temperature and precipitation effected the growing environment, leading to differences in yield and water footprint. The field experiments in this area may benefit from further water footprint studies at the global, national and regional scale. © 2016 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2016 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of

Study on Semi-Parametric Statistical Model of Safety Monitoring of Cracks in Concrete Dams

Directory of Open Access Journals (Sweden)

Chongshi Gu

2013-01-01

Full Text Available Cracks are one of the hidden dangers in concrete dams. The study on safety monitoring models of concrete dam cracks has always been difficult. Using the parametric statistical model of safety monitoring of cracks in concrete dams, with the help of the semi-parametric statistical theory, and considering the abnormal behaviors of these cracks, the semi-parametric statistical model of safety monitoring of concrete dam cracks is established to overcome the limitation of the parametric model in expressing the objective model. Previous projects show that the semi-parametric statistical model has a stronger fitting effect and has a better explanation for cracks in concrete dams than the parametric statistical model. However, when used for forecast, the forecast capability of the semi-parametric statistical model is equivalent to that of the parametric statistical model. The modeling of the semi-parametric statistical model is simple, has a reasonable principle, and has a strong practicality, with a good application prospect in the actual project.

P-wave dispersion in endogenous and exogenous subclinical hyperthyroidism.

Science.gov (United States)

Gen, R; Akbay, E; Camsari, A; Ozcan, T

2010-02-01

The aim of this study was to measure maximum P wave duration (Pmax) and P wave dispersion (PWD), which can be indicators for the risk of paroxysmal atrial fibrillation when increased, and to reveal their relationship with thyroid hormone levels in patients with endogenous and exogenous subclinical hyperthyroidism. Seventy-one patients with sublinical thyrotoxicosis (34 endogenous, 37 exogenous) and 69 healthy individuals were enrolled in the study. Pmax and minimum P wave duration (Pmin) on electrocardiogram recordings were measured and PWD was calculated as Pmax-Pmin. Pmax (pendogenous subclinical hyperthyroidism compared with the control group. Pmax (pexogenous subclinical thyrotoxicosis compared with the control group. Pmax (p=0.710) and PWD (p=0.127) were not significantly different in patients with endogenous subclinical hyperthyroidism compared with exogenous subclinical hyperthyroid patients. Pmax and PWD negatively associated with TSH in endogenous and exogenous subclinical hyperthyroidism. In the present study, we observed that Pmax and PWD were longer in patients with endogenous and exogenous subclinical hyperthyroidism. Lack of a difference in Pmax and PWD between patients with endogenous and exogenous subclinical hyperthyroidism seems to support the idea that hormone levels rather than the etiology of thyrotoxicosis affect the heart.

Endogene CGRP

OpenAIRE

Höfer, Martina

2010-01-01

Hintergrund und Ziele Die vorliegende tierexperimentelle Arbeit beschäftigt sich mit der Frage, welche Rolle endogenes Calcitonin-gene related peptide (CGRP) in der Niere spielt. Hierbei untersuchten wir die renale CGRP Freisetzung aus renalen Afferenzen in vitro anhand von gesunden Tieren und einem pathologischen Modell der Glomerulonephritis. Man weiß bereits, dass sowohl sympathische als auch primär sensorische Neuronen die Entzündung und die Immunantwort in der Peripherie regulieren (68)....

[The endogenous opioid system and drug addiction].

Science.gov (United States)

Maldonado, R

2010-01-01

Drug addiction is a chronic brain disorder leading to complex adaptive changes within the brain reward circuits. Several neurotransmitters, including the endogenous opioid system are involved in these changes. The opioid system plays a pivotal role in different aspects of addiction. Thus, opioid receptors and endogenous opioid peptides are largely distributed in the mesolimbic system and modulate dopaminergic activity within the reward circuits. Opioid receptors and peptides are selectively involved in several components of the addictive processes induced by opioids, cannabinoids, psychostimulants, alcohol and nicotine. This review is focused on the contribution of each component of the endogenous opioid system in the addictive properties of the different drugs of abuse. Copyright 2010 Elsevier Masson SAS. All rights reserved.

Endogenous Growth and Comparative Standards of Living between Mexico and the US

OpenAIRE

Alejandro Rodríguez Arana

2005-01-01

This paper calibrates an AK model of growth for Mexico. Investment financing is modeled considering the domestic savings ratio as well as net factorial income and capital inflows of the balance of payments. Productivity A and the rate of depreciation of capital are found using econometric techniques. According to this model, actual parameters determining growth in Mexico are compatible with a sustained long run rate of growth of about 3.6%. At the same time, under these circumstances the rati...

Revisiting a model of ontogenetic growth: estimating model parameters from theory and data.

Science.gov (United States)

Moses, Melanie E; Hou, Chen; Woodruff, William H; West, Geoffrey B; Nekola, Jeffery C; Zuo, Wenyun; Brown, James H

2008-05-01

The ontogenetic growth model (OGM) of West et al. provides a general description of how metabolic energy is allocated between production of new biomass and maintenance of existing biomass during ontogeny. Here, we reexamine the OGM, make some minor modifications and corrections, and further evaluate its ability to account for empirical variation on rates of metabolism and biomass in vertebrates both during ontogeny and across species of varying adult body size. We show that the updated version of the model is internally consistent and is consistent with other predictions of metabolic scaling theory and empirical data. The OGM predicts not only the near universal sigmoidal form of growth curves but also the M(1/4) scaling of the characteristic times of ontogenetic stages in addition to the curvilinear decline in growth efficiency described by Brody. Additionally, the OGM relates the M(3/4) scaling across adults of different species to the scaling of metabolic rate across ontogeny within species. In providing a simple, quantitative description of how energy is allocated to growth, the OGM calls attention to unexplained variation, unanswered questions, and opportunities for future research.

Matching theory for wireless networks

CERN Document Server

Han, Zhu; Saad, Walid

2017-01-01

This book provides the fundamental knowledge of the classical matching theory problems. It builds up the bridge between the matching theory and the 5G wireless communication resource allocation problems. The potentials and challenges of implementing the semi-distributive matching theory framework into the wireless resource allocations are analyzed both theoretically and through implementation examples. Academics, researchers, engineers, and so on, who are interested in efficient distributive wireless resource allocation solutions, will find this book to be an exceptional resource. .

On climate change and economic growth

International Nuclear Information System (INIS)

Fankhauser, Samuel; Tol, Richard S.J.

2005-01-01

The economic impact of climate change is usually measured as the extent to which the climate of a given period affects social welfare in that period. This static approach ignores the dynamic effects through which climate change may affect economic growth and hence future welfare. In this paper we take a closer look at these dynamic effects, in particular saving and capital accumulation. With a constant savings rate, a lower output due to climate change will lead to a proportionate reduction in investment which in turn will depress future production (capital accumulation effect) and, in almost all cases, future consumption per capita. If the savings rate is endogenous, forward looking agents would change their savings behavior to accommodate the impact of future climate change. This suppresses growth prospects in absolute and per capita terms (savings effect). In an endogenous growth context, these two effects may be exacerbated through changes in labour productivity and the rate of technical progress. Simulations using a simple climate-economy model suggest that the capital accumulation effect is important, especially if technological change is endogenous, and may be larger than the direct impact of climate change. The savings effect is less pronounced. The dynamic effects are more important, relative to the direct effects, if climate change impacts are moderate overall. This suggests that they are more of a concern in developed countries, which are believed to be less vulnerable to climate change. The magnitude of dynamic effects is not sensitive to the choice of discount rate

Endogenous Money Supply and Money Demand

OpenAIRE

Woon Gyu Choi; Seonghwan Oh

2000-01-01

This paper explores the behavior of money demand by explicitly accounting for the money supply endogeneity arising from endogenous monetary policy and financial innovations. Our theoretical analysis indicates that money supply factors matter in the money demand function when the money supply partially responds to money demand. Our empirical results with U.S. data provide strong evidence for the relevance of the policy stance to the demand for MI under a regime in which monetary policy is subs...

Gas-liquid reactive crystallization kinetics of 2,4,6-triamino-1,3,5-trinitrobenzene in the semi-batch procedure

Science.gov (United States)

Liu, Ruqin; Huang, Ming; Yao, Xiaolu; Chen, Shuang; Wang, Shucun; Suo, Zhirong