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1

Uncertainty quantification theory, implementation, and applications

The field of uncertainty quantification is evolving rapidly because of increasing emphasis on models that require quantified uncertainties for large-scale applications, novel algorithm development, and new computational architectures that facilitate implementation of these algorithms. Uncertainty Quantification: Theory, Implementation, and Applications provides readers with the basic concepts, theory, and algorithms necessary to quantify input and response uncertainties for simulation models arising in a broad range of disciplines. The book begins with a detailed discussion of applications where uncertainty quantification is critical for both scientific understanding and policy. It then covers concepts from probability and statistics, parameter selection techniques, frequentist and Bayesian model calibration, propagation of uncertainties, quantification of model discrepancy, surrogate model construction, and local and global sensitivity analysis. The author maintains a complementary web page where readers ca...

Smith, Ralph C

2014-01-01

2

Densitometric quantification of ether-type phospholipids.

A quantification method for analysis of individual ether-type phospholipids is important in studies of the regulation of membrane lipid biosynthesis in Archaea. For ester-type lipid of Bacteria and Eucarya, a densitometric method has been established for simultaneous quantification of individual phospholipids visualized with molybdenum blue reagent on a TLC plate. In this study, we developed a TLC densitometric method for rapid quantitative determination of 6 kinds of main ether-type phospholipids in a methanogenic archaeon and an extremely halophilic archaeon. It has been reported previously that on densitometric quantification the values of molar absorptivities are approximately the same among most ester-type phospholipids. On the other hand, we found significant disparity in the molar absorptivity of archaeal ether-type lipids and serine-containing ester-type lipid. Therefore, analysis should be accomplished by use of each standard mixture. Compared with a previous method (preparative TLC method) that is measurement of inorganic phosphate of silica gel powder scraped off from spots of phospholipids on a TLC plate, the TLC densitometry is accomplished at one tenth the sample size in a short time. PMID:18783009

Oe, Shinji; Tanaka, Takahiro; Ohga, Mami; Koga, Yosuke; Morii, Hiroyuki

2008-09-01

3

Utilizing general information theories for uncertainty quantification

Energy Technology Data Exchange (ETDEWEB)

Uncertainties enter into a complex problem from many sources: variability, errors, and lack of knowledge. A fundamental question arises in how to characterize the various kinds of uncertainty and then combine within a problem such as the verification and validation of a structural dynamics computer model, reliability of a dynamic system, or a complex decision problem. Because uncertainties are of different types (e.g., random noise, numerical error, vagueness of classification), it is difficult to quantify all of them within the constructs of a single mathematical theory, such as probability theory. Because different kinds of uncertainty occur within a complex modeling problem, linkages between these mathematical theories are necessary. A brief overview of some of these theories and their constituents under the label of Generalized lnforrnation Theory (GIT) is presented, and a brief decision example illustrates the importance of linking at least two such theories.

Booker, J. M. (Jane M.)

2002-01-01

4

Recurrence quantification analysis theory and best practices

The analysis of recurrences in dynamical systems by using recurrence plots and their quantification is still an emerging field. Over the past decades recurrence plots have proven to be valuable data visualization and analysis tools in the theoretical study of complex, time-varying dynamical systems as well as in various applications in biology, neuroscience, kinesiology, psychology, physiology, engineering, physics, geosciences, linguistics, finance, economics, and other disciplines. This multi-authored book intends to comprehensively introduce and showcase recent advances as well as established best practices concerning both theoretical and practical aspects of recurrence plot based analysis. Edited and authored by leading researcher in the field, the various chapters address an interdisciplinary readership, ranging from theoretical physicists to application-oriented scientists in all data-providing disciplines.

Jr, Jr; Marwan, Norbert

2015-01-01

5

An approximation approach for uncertainty quantification using evidence theory

Energy Technology Data Exchange (ETDEWEB)

Over the last two decades, uncertainty quantification (UQ) in engineering systems has been performed by the popular framework of probability theory. However, many scientific and engineering communities realize that there are limitations in using only one framework for quantifying the uncertainty experienced in engineering applications. Recently evidence theory, also called Dempster-Shafer theory, was proposed to handle limited and imprecise data situations as an alternative to the classical probability theory. Adaptation of this theory for large-scale engineering structures is a challenge due to implicit nature of simulations and excessive computational costs. In this work, an approximation approach is developed to improve the practical utility of evidence theory in UQ analysis. The techniques are demonstrated on composite material structures and airframe wing aeroelastic design problem.

Bae, Ha-Rok; Grandhi, Ramana V.; Canfield, Robert A

2004-12-01

6

An approximation approach for uncertainty quantification using evidence theory

International Nuclear Information System (INIS)

Over the last two decades, uncertainty quantification (UQ) in engineering systems has been performed by the popular framework of probability theory. However, many scientific and engineering communities realize that there are limitations in using only one framework for quantifying the uncertainty experienced in engineering applications. Recently evidence theory, also called Dempster-Shafer theory, was proposed to handle limited and imprecise data situations as an alternative to the classical probability theory. Adaptation of this theory for large-scale engineering structures is a challenge due to implicit nature of simulations and excessive computational costs. In this work, an approximation approach is developed to improve the practical utility of evidence theory in UQ analysis. The techniques are demonstrated on composite material structures and airframe wing aeroelastic design problem

7

Inductive types in homotopy type theory

Homotopy type theory is an interpretation of Martin-L\\"of's constructive type theory into abstract homotopy theory. There results a link between constructive mathematics and algebraic topology, providing topological semantics for intensional systems of type theory as well as a computational approach to algebraic topology via type theory-based proof assistants such as Coq. The present work investigates inductive types in this setting. Modified rules for inductive types, including types of well-founded trees, or W-types, are presented, and the basic homotopical semantics of such types are determined. Proofs of all results have been formally verified by the Coq proof assistant, and the proof scripts for this verification form an essential component of this research.

Awodey, Steve; Sojakova, Kristina

2012-01-01

8

On Irrelevance and Algorithmic Equality in Predicative Type Theory

Dependently typed programs contain an excessive amount of static terms which are necessary to please the type checker but irrelevant for computation. To separate static and dynamic code, several static analyses and type systems have been put forward. We consider Pfenning's type theory with irrelevant quantification which is compatible with a type-based notion of equality that respects eta-laws. We extend Pfenning's theory to universes and large eliminations and develop its meta-theory. Subject reduction, normalization and consistency are obtained by a Kripke model over the typed equality judgement. Finally, a type-directed equality algorithm is described whose completeness is proven by a second Kripke model.

Abel, Andreas

2012-01-01

9

Type Classes for Mathematics in Type Theory

The introduction of first-class type classes in the Coq system calls for re-examination of the basic interfaces used for mathematical formalization in type theory. We present a new set of type classes for mathematics and take full advantage of their unique features to make practical a particularly flexible approach formerly thought infeasible. Thus, we address both traditional proof engineering challenges as well as new ones resulting from our ambition to build upon this development a library of constructive analysis in which abstraction penalties inhibiting efficient computation are reduced to a minimum. The base of our development consists of type classes representing a standard algebraic hierarchy, as well as portions of category theory and universal algebra. On this foundation we build a set of mathematically sound abstract interfaces for different kinds of numbers, succinctly expressed using categorical language and universal algebra constructions. Strategic use of type classes lets us support these high...

Spitters, Bas

2011-01-01

10

Treatise on Intuitionistic Type Theory

Intuitionistic type theory can be described, somewhat boldly, as a partial fulfillment of the dream of a universal language for science. This book expounds several aspects of intuitionistic type theory, such as the notion of set, reference vs. computation, assumption, and substitution. Moreover, the book includes philosophically relevant sections on the principle of compositionality, lingua characteristica, epistemology, propositional logic, intuitionism, and the law of excluded middle. Ample historical references are given throughout the book.

Granstrom, Johan Georg

2011-01-01

11

Classical field theory via Cohesive homotopy types

A brief survey of how classical field theory emerges synthetically in cohesive homotopy type theory. Extended Conference Abstract submitted to the proceedings of the Conference on Type Theory, Homotopy Theory and Univalent Foundations in Barcelona, Fall 2013

Schreiber, Urs

2013-01-01

12

Quantification of Uncertainties in Nuclear Density Functional theory

Digital Repository Infrastructure Vision for European Research (DRIVER)

Reliable predictions of nuclear properties are needed as much to answer fundamental science questions as in applications such as reactor physics or data evaluation. Nuclear density functional theory is currently the only microscopic, global approach to nuclear structure that is applicable throughout the nuclear chart. In the past few years, a lot of effort has been devoted to setting up a general methodology to assess theoretical uncertainties in nuclear DFT calculations. In...

Schunck, N.; Mcdonnell, J. D.; Higdon, D.; Sarich, J.; Wild, S.

2014-01-01

13

Quantification of Uncertainties in Nuclear Density Functional theory

Reliable predictions of nuclear properties are needed as much to answer fundamental science questions as in applications such as reactor physics or data evaluation. Nuclear density functional theory is currently the only microscopic, global approach to nuclear structure that is applicable throughout the nuclear chart. In the past few years, a lot of effort has been devoted to setting up a general methodology to assess theoretical uncertainties in nuclear DFT calculations. In this paper, we summarize some of the recent progress in this direction. Most of the new material discussed here will be be published in separate articles.

Schunck, N; Higdon, D; Sarich, J; Wild, S

2014-01-01

14

Completeness in Hybrid Type Theory

DEFF Research Database (Denmark)

We show that basic hybridization (adding nominals and @ operators) makes it possible to give straightforward Henkin- style completeness proofs even when the modal logic being hybridized is higher-order. The key ideas are to add nomi- nals as expressions of type t, and to extend to arbitrary types the way we interpret @i in propositional and rst-order hybrid logic. This means: interpret @ia, where a is an expression of any type a, as an expression of type a that rigidly returns the value that a receives at the i-world. The axiomatization and completeness proofs are generalizations of those found in propositional and rst-order hybrid logic, and (as is usual in hybrid logic) we automatically obtain a wide range of complete- ness results for stronger logics and languages. Our approach is deliberately low-tech. We don't, for example, make use of Mon- tague's intensional type s, or Fitting-style intensional models; we build, as simply as we can, hybrid logic over Henkin's logic.

Areces, Carlos; Blackburn, Patrick Rowan

2014-01-01

15

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Gene expression microarray and other multiplex data hold promise for addressing the challenges of cellular complexity, refined diagnoses and the discovery of well-targeted treatments. A new approach to the construction and quantification of transcriptional regulatory networks (TRNs is presented that integrates gene expression microarray data and cell modeling through information theory. Given a partial TRN and time series data, a probability density is constructed that is a functional of the time course of transcription factor (TF thermodynamic activities at the site of gene control, and is a function of mRNA degradation and transcription rate coefficients, and equilibrium constants for TF/gene binding. Results Our approach yields more physicochemical information that compliments the results of network structure delineation methods, and thereby can serve as an element of a comprehensive TRN discovery/quantification system. The most probable TF time courses and values of the aforementioned parameters are obtained by maximizing the probability obtained through entropy maximization. Observed time delays between mRNA expression and activity are accounted for implicitly since the time course of the activity of a TF is coupled by probability functional maximization, and is not assumed to be proportional to expression level of the mRNA type that translates into the TF. This allows one to investigate post-translational and TF activation mechanisms of gene regulation. Accuracy and robustness of the method are evaluated. A kinetic formulation is used to facilitate the analysis of phenomena with a strongly dynamical character while a physically-motivated regularization of the TF time course is found to overcome difficulties due to omnipresent noise and data sparsity that plague other methods of gene expression data analysis. An application to Escherichia coli is presented. Conclusion Multiplex time series data can be used for the construction of the network of cellular processes and the calibration of the associated physicochemical parameters. We have demonstrated these concepts in the context of gene regulation understood through the analysis of gene expression microarray time series data. Casting the approach in a probabilistic framework has allowed us to address the uncertainties in gene expression microarray data. Our approach was found to be robust to error in the gene expression microarray data and mistakes in a proposed TRN.

Tuncay Kagan

2007-01-01

16

Type II string theory and modularity

International Nuclear Information System (INIS)

This paper, in a sense, completes a series of three papers. In the previous two, we have explored the possibility of refining the K-theory partition function in type II string theories using elliptic cohomology. In the present paper, we make that more concrete by defining a fully quantized free field theory based on elliptic cohomology of 10-dimensional spacetime. Moreover, we describe a concrete scenario how this is related to compactification of F-theory on an elliptic curve leading to IIA and IIB theories. We propose an interpretation of the elliptic curve in the context of elliptic cohomology. We discuss the possibility of orbifolding of the elliptic curves and derive certain properties of F-theory. We propose a link of this to type IIB modularity, the structure of the topological lagrangian of M-theory, and Witten's index of loop space Dirac operators. The discussion suggests a S1-lift of type IIB and an F-theoretic model for type I obtained by orbifolding that for type IIB

17

Type II string theory and modularity

Energy Technology Data Exchange (ETDEWEB)

This paper, in a sense, completes a series of three papers. In the previous two, we have explored the possibility of refining the K-theory partition function in type II string theories using elliptic cohomology. In the present paper, we make that more concrete by defining a fully quantized free field theory based on elliptic cohomology of 10-dimensional spacetime. Moreover, we describe a concrete scenario how this is related to compactification of F-theory on an elliptic curve leading to IIA and IIB theories. We propose an interpretation of the elliptic curve in the context of elliptic cohomology. We discuss the possibility of orbifolding of the elliptic curves and derive certain properties of F-theory. We propose a link of this to type IIB modularity, the structure of the topological lagrangian of M-theory, and Witten's index of loop space Dirac operators. The discussion suggests a S{sup 1}-lift of type IIB and an F-theoretic model for type I obtained by orbifolding that for type IIB.

Kriz, Igor [Department of Mathematics, University of Michigan, Ann Arbor, MI 48109 (United States); Sati, Hisham [Department of Physics, University of Adelaide, Adelaide, SA 5005 (Australia); Department of Pure Mathematics, University of Adelaide, Adelaide, SA 5005 (Australia)

2005-08-01

18

Divergence-type theory of conformal fields

Digital Repository Infrastructure Vision for European Research (DRIVER)

We present a nonlinear hydrodynamical description of a conformal plasma within the framework of divergence-type theories (DTTs), which are not based on a gradient expansion. We compare the equations of the DTT and the second-order theory (based on conformal invariants), for the case of Bjorken ow. The approach to ideal hydrodynamics is faster in the DTT, indicating that our results can be useful in the study of early-time dynamics in relativistic heavy-ion collisions.

Peralta-ramos, J.; Calzetta, E.

2009-01-01

19

Penner type ensemble for gauge theories revisited

The Penner type ? ensemble for ?-deformed N=2SU(2) gauge theory with two massless flavors arising as a limiting case from the Alday, Gaiotto and Tachikawa conjecture is considered. The partition function can be calculated perturbatively in a saddle-point approximation. A large N limit reproduces the gauge theory partition function expanded in a strong coupling regime, for any ? and beyond tree level, confirming previous results obtained via special geometry and the holomorphic anomaly equation. The leading terms and gap of the gauge theory free energy at the monopole/dyon point follow as a corollary.

Krefl, Daniel

2013-02-01

20

Penner Type Ensemble for Gauge Theories Revisited

The Penner type beta-ensemble for Omega-deformed N=2 SU(2) gauge theory with two massless flavors arising as a limiting case from the AGT conjecture is considered. The partition function can be calculated perturbatively in a saddle-point approximation. A large N limit reproduces the gauge theory partition function expanded in a strong coupling regime, for any beta and beyond tree-level, confirming previous results obtained via special geometry and the holomorphic anomaly equation. The leading terms and gap of the gauge theory free energy at the monopole/dyon point follow as a corollary.

Krefl, Daniel

2012-01-01

21

Explicit Substitutions for Contextual Type Theory

In this paper, we present an explicit substitution calculus which distinguishes between ordinary bound variables and meta-variables. Its typing discipline is derived from contextual modal type theory. We first present a dependently typed lambda calculus with explicit substitutions for ordinary variables and explicit meta-substitutions for meta-variables. We then present a weak head normalization procedure which performs both substitutions lazily and in a single pass thereby combining substitution walks for the two different classes of variables. Finally, we describe a bidirectional type checking algorithm which uses weak head normalization and prove soundness.

Abel, Andreas; 10.4204/EPTCS.34.3

2010-01-01

22

Directory of Open Access Journals (Sweden)

Full Text Available Implementasi penjaminan mutu akademik tentu saja berkaitan erat dengan pelaku utama proses akademik di sebuah perguruan tinggi, yaitu dosen. Untuk itu perlu dilakukan evaluasi kinerja dosen. Indeks kinerja dosen (IKD UIN terdiri dari tiga komponen penilaian, yaitu meliputi : Kehadiran mengajar dikelas (K1 sebesar 30%, Ketepatan waktu penyerahan nilai (K2 sebesar 30% dan Penilaian mahasiswa (K3 sebesar 40%. Selain penilaian mahasiswa yang bersifat kualitatif, IKD juga dipengaruhi oleh variabel kehadiran dosen dalam mengajar dan ketepatan penyerahan nilai, yang jelas terukur. Untuk menghubungkan antara faktor kualitatif dan kuantitatif, dapat digunakan fuzzy quantification theory I. Metode yang digunakan untuk pengambilan sampel data adalah multistage random sampling dan analisis data dengan fuzzy quantification theory untuk menentukan seberapa besar faktor-faktor kualitatif penilaian mahasiswa dan kehadiran dosen mempengaruhi prestasi nilai matakuliah mahasiswa UIN Sunan Kalijaga. Hasil penelitian menunjukkan bahwa Indeks kinerja dosen (hasil penilaian mahasiswa dan jumlah kehadiran mengajar dosen hanya mampu memberikan pengaruh terhadap prestasi nilai matakuliah mahasiswa Universitas Islam Negeri (UIN Sunan Kalijaga sebesar 68,58 %. Disiplin terhadap ketepatan waktu kuliah dan kemampuan dosen untuk meningkatkan minat belajar mahasiswa memiliki pengaruh yang paling tinggi terhadap prestasi nilai matakuliah mahasiswa UIN Sunan Kalijaga. Pengaruh ini akan sangat kuat apabila kehadiran dosen mengajar lebih dari 10 kali.

Shofwatul ‘Uyun

2012-05-01

23

Predictions for orientifold field theories from type 0' string theory

Two predictions about finite-N non-supersymmetric "orientifold field theories" are made by using the dual type 0' string theory on C^3 / Z_2 x Z_2 orbifold singularity. First, the mass ratio between the lowest pseudoscalar and scalar color-singlets is estimated to be equal to the ratio between the axial anomaly and the scale anomaly at strong coupling, M_- / M_+ ~ C_- / C_+. Second, the ratio between the domain wall tension and the value of the quark condensate is computed.

Armoni, A

2005-01-01

24

Hoare type theory, polymorphism and separation

DEFF Research Database (Denmark)

We consider the problem of reconciling a dependently typed functional language with imperative features such as mutable higher-order state, pointer aliasing, and nontermination. We propose Hoare type theory (HTT), which incorporates Hoare-style specifications into types, making it possible to statically track and enforce correct use of side effects. The main feature of HTT is the Hoare type {P}x:A{Q} specifying computations with precondition P and postcondition Q that return a result of type A. Hoare types can be nested, combined with other types, and abstracted, leading to a smooth integration with higher-order functions and type polymorphism. We further show that in the presence of type polymorphism, it becomes possible to interpret the Hoare types in the “small footprint” manner, as advocated by separation logic, whereby specifications tightly describe the state required by the computation. We establish that HTT is sound and compositional, in the sense that separate verifications of individual program components suffice to ensure the correctness of the composite program.

Nanevski, Alexandar; Morrisett, J. Gregory

2008-01-01

25

Renormalization group in Lifshitz-type theories

International Nuclear Information System (INIS)

We study the one-loop renormalization and evolution of the couplings in scalar field theories of the Lifshitz type, i.e. with different scaling in space and time. These theories are unitary and renormalizable, thanks to higher spatial derivative terms that modify the particle propagator at high energies, but at the expense of explicitly breaking Lorentz symmetry. We study if and under what conditions the Lorentz symmetry can be considered as emergent at low energies by studying the RG evolution of the 'speed of light' coupling c2? and, for more than one field, of ?c2?c2?1-c2?2 in simple models. We find that in the UV both c2? and ?c2 generally flow logarithmically with the energy scale. A logarithmic running of c2 persists also at low-energies, if ?c2?0 in the UV. As a result, Lorentz symmetry is not recovered at low energies with the accuracy needed to withstand basic experimental constraints, unless all the Lorentz breaking terms, including ?c2, are unnaturally fine-tuned to extremely small values in the UV. We expect that the considerations of this paper will apply to any generic theory of Lifshitz type, including a recently proposed quantum theory of gravity by Horava.

26

Classical Predicative Logic-Enriched Type Theories

A logic-enriched type theory (LTT) is a type theory extended with a primitive mechanism for forming and proving propositions. We construct two LTTs, named LTTO and LTTO*, which we claim correspond closely to the classical predicative systems of second order arithmetic ACAO and ACA. We justify this claim by translating each second-order system into the corresponding LTT, and proving that these translations are conservative. This is part of an ongoing research project to investigate how LTTs may be used to formalise different approaches to the foundations of mathematics. The two LTTs we construct are subsystems of the logic-enriched type theory LTTW, which is intended to formalise the classical predicative foundation presented by Herman Weyl in his monograph Das Kontinuum. The system ACAO has also been claimed to correspond to Weyl's foundation. By casting ACAO and ACA as LTTs, we are able to compare them with LTTW. It is a consequence of the work in this paper that LTTW is strictly stronger than ACAO. The cons...

Adams, Robin

2009-01-01

27

We assess the effectiveness of applying information theory to the characterization and quantification of the affects of anthropogenic vessel noise on humpback whale (Megaptera novaeangliae) vocal behavior in and around Glacier Bay, Alaska. Vessel noise has the potential to interfere with the complex vocal behavior of these humpback whales which could have direct consequences on their feeding behavior and thus ultimately on their health and reproduction. Humpback whale feeding calls recorded during conditions of high vessel-generated noise and lower levels of background noise are compared for differences in acoustic structure, use, and organization using information theoretic measures. We apply information theory in a self-referential manner (i.e., orders of entropy) to quantify the changes in signaling behavior. We then compare this with the reduction in channel capacity due to noise in Glacier Bay itself treating it as a (Gaussian) noisy channel. We find that high vessel noise is associated with an increase in the rate and repetitiveness of sequential use of feeding call types in our averaged sample of humpback whale vocalizations, indicating that vessel noise may be modifying the patterns of use of feeding calls by the endangered humpback whales in Southeast Alaska. The information theoretic approach suggested herein can make a reliable quantitative measure of such relationships and may also be adapted for wider application to many species where environmental noise is thought to be a problem.

Doyle, Laurance R.; McCowan, Brenda; Hanser, Sean F.; Chyba, Christopher; Bucci, Taylor; Blue, J. E.

2008-06-01

28

Directory of Open Access Journals (Sweden)

Full Text Available We assess the effectiveness of applying information theory to the characterization and quantification of the affects of anthropogenic vessel noise on humpback whale (Megaptera novaeangliae vocal behavior in and around Glacier Bay, Alaska. Vessel noise has the potential to interfere with the complex vocal behavior of these humpback whales which could have direct consequences on their feeding behavior and thus ultimately on their health and reproduction. Humpback whale feeding calls recorded during conditions of high vessel-generated noise and lower levels of background noise are compared for differences in acoustic structure, use, and organization using information theoretic measures. We apply information theory in a self-referential manner (i.e., orders of entropy to quantify the changes in signaling behavior. We then compare this with the reduction in channel capacity due to noise in Glacier Bay itself treating it as a (Gaussian noisy channel. We find that high vessel noise is associated with an increase in the rate and repetitiveness of sequential use of feeding call types in our averaged sample of humpback whale vocalizations, indicating that vessel noise may be modifying the patterns of use of feeding calls by the endangered humpback whales in Southeast Alaska. The information theoretic approach suggested herein can make a reliable quantitative measure of such relationships and may also be adapted for wider application to many species where environmental noise is thought to be a problem.

J. Ellen Blue

2008-05-01

29

Bell-type quantum field theories

International Nuclear Information System (INIS)

In his paper (1986 Beables for quantum field theory Phys. Rep. 137 49-54) John S Bell proposed how to associate particle trajectories with a lattice quantum field theory, yielding what can be regarded as a vertical bar ? vertical bar2-distributed Markov process on the appropriate configuration space. A similar process can be defined in the continuum, for more or less any regularized quantum field theory; we call such processes Bell-type quantum field theories. We describe methods for explicitly constructing these processes. These concern, in addition to the definition of the Markov processes, the efficient calculation of jump rates, how to obtain the process from the processes corresponding to the free and interaction Hamiltonian alone, and how to obtain the free process from the free Hamiltonian or, alternatively, from the one-particle process by a construction analogous to 'second quantization'. As an example, we consider the process for a second quantized Dirac field in an external electromagnetic field. (topical review)

30

Multi-level Contextual Type Theory

Directory of Open Access Journals (Sweden)

Full Text Available Contextual type theory distinguishes between bound variables and meta-variables to write potentially incomplete terms in the presence of binders. It has found good use as a framework for concise explanations of higher-order unification, characterize holes in proofs, and in developing a foundation for programming with higher-order abstract syntax, as embodied by the programming and reasoning environment Beluga. However, to reason about these applications, we need to introduce meta^2-variables to characterize the dependency on meta-variables and bound variables. In other words, we must go beyond a two-level system granting only bound variables and meta-variables. In this paper we generalize contextual type theory to n levels for arbitrary n, so as to obtain a formal system offering bound variables, meta-variables and so on all the way to meta^n-variables. We obtain a uniform account by collapsing all these different kinds of variables into a single notion of variabe indexed by some level k. We give a decidable bi-directional type system which characterizes beta-eta-normal forms together with a generalized substitution operation.

Mathieu Boespflug

2011-10-01

31

Digital Repository Infrastructure Vision for European Research (DRIVER)

We assess the effectiveness of applying information theory to the characterization and quantification of the affects of anthropogenic vessel noise on humpback whale (Megaptera novaeangliae) vocal behavior in and around Glacier Bay, Alaska. Vessel noise has the potential to interfere with the complex vocal behavior of these humpback whales which could have direct consequences on their feeding behavior and thus ultimately on their health and reproduction. Humpback whale feeding calls recorded d...

Ellen Blue, J.; Taylor Bucci; Christopher Chyba; Hanser, Sean F.; Brenda McCowan; Doyle, Laurance R.

2008-01-01

32

Uncertainty Quantification of Composite Laminate Damage with the Generalized Information Theory

Energy Technology Data Exchange (ETDEWEB)

This work presents a survey of five theories to assess the uncertainty of projectile impact induced damage on multi-layered carbon-epoxy composite plates. Because the types of uncertainty dealt with in this application are multiple (variability, ambiguity, and conflict) and because the data sets collected are sparse, characterizing the amount of delamination damage with probability theory alone is possible but incomplete. This motivates the exploration of methods contained within a broad Generalized Information Theory (GIT) that rely on less restrictive assumptions than probability theory. Probability, fuzzy sets, possibility, and imprecise probability (probability boxes (p-boxes) and Dempster-Shafer) are used to assess the uncertainty in composite plate damage. Furthermore, this work highlights the usefulness of each theory. The purpose of the study is not to compare directly the different GIT methods but to show that they can be deployed on a practical application and to compare the assumptions upon which these theories are based. The data sets consist of experimental measurements and finite element predictions of the amount of delamination and fiber splitting damage as multilayered composite plates are impacted by a projectile at various velocities. The physical experiments consist of using a gas gun to impact suspended plates with a projectile accelerated to prescribed velocities, then, taking ultrasound images of the resulting delamination. The nonlinear, multiple length-scale numerical simulations couple local crack propagation implemented through cohesive zone modeling to global stress-displacement finite element analysis. The assessment of damage uncertainty is performed in three steps by, first, considering the test data only; then, considering the simulation data only; finally, performing an assessment of total uncertainty where test and simulation data sets are combined. This study leads to practical recommendations for reducing the uncertainty and improving the prediction accuracy of the damage modeling and finite element simulation.

J. Lucero; F. Hemez; T. Ross; K.Kline; J.Hundhausen; T. Tippetts

2006-05-01

33

We extract the statistical uncertainties for the pion-nucleon ($\\pi N$) low energy constants (LECs) up to fourth order $\\mathcal{O}(Q^4)$ in the chiral expansion of the nuclear effective Lagrangian. The LECs are optimized with respect to experimental scattering data. For comparison, we also present an uncertainty quantification that is based solely on \\pin{} scattering phase shifts. Statistical errors on the LECs are critical in order to estimate the subsequent uncertainties in \\textit{ab initio} modeling of light and medium mass nuclei which exploit chiral effective field theory. As an example of the this, we present the first complete predictions with uncertainty quantification of peripheral phase shifts of elastic proton-neutron scattering.

Wendt, K A; Ekström, A

2014-01-01

34

Simple Type Theory as Framework for Combining Logics

Simple type theory is suited as framework for combining classical and non-classical logics. This claim is based on the observation that various prominent logics, including (quantified) multimodal logics and intuitionistic logics, can be elegantly embedded in simple type theory. Furthermore, simple type theory is sufficiently expressive to model combinations of embedded logics and it has a well understood semantics. Off-the-shelf reasoning systems for simple type theory exist that can be uniformly employed for reasoning within and about combinations of logics.

Benzmueller, Christoph

2010-01-01

35

Orbifolds of M-theory and type II string theories in two dimensions

International Nuclear Information System (INIS)

We consider several orbifold compactifications of M-theory and theircorresponding type II duals in two space-time dimensions. In particular, we show that while the orbifold compactification of M-theory on T9/J9 is dual to the orbifold compactification of type IIB string theory on T8/I8, the same orbifold T8/I8 of type IIA string theory is dual to M-theory compactified on a smooth product manifold K3 x T5. Similarly, while the orbifold compactification of M-theory on (K3 x T5)/?. J5 is dual to the orbifold compactification of type IIB string theory on (K3 x T4)/?.I4, the same orbifold of type IIA string theory is dual to the orbifold T4 x (K3 x S1)/?.J1 of M-theory. The spectrum of various orbifold compactifications of M-theory and type II string theories on both sides are compared giving evidence in favor of these duality conjectures. We also comment on a connection between the Dasgupta-Mukhi-Witten conjecture and the Dabholkar-Park-Sen conjecture for the six-dimensional orbifold models of type IIB string theory and M-theory. (orig.)

36

Toward a Theory of Psychological Type Congruence for Advertisers.

Focusing on the impact of advertisers' persuasive selling messages on consumers, this paper discusses topics relating to the theory of psychological type congruence. Based on an examination of persuasion theory and relevant psychological concepts, including recent cognitive stability and personality and needs theory and the older concept of…

McBride, Michael H.; And Others

37

Simplex stochastic collocation with ENO-type stencil selection for robust uncertainty quantification

Multi-element uncertainty quantification approaches can robustly resolve the high sensitivities caused by discontinuities in parametric space by reducing the polynomial degree locally to a piecewise linear approximation. It is important to extend the higher degree interpolation in the smooth regions up to a thin layer of linear elements that contain the discontinuity to maintain a highly accurate solution. This is achieved here by introducing Essentially Non-Oscillatory (ENO) type stencil selection into the Simplex Stochastic Collocation (SSC) method. For each simplex in the discretization of the parametric space, the stencil with the highest polynomial degree is selected from the set of candidate stencils to construct the local response surface approximation. The application of the resulting SSC-ENO method to a discontinuous test function shows a sharper resolution of the jumps and a higher order approximation of the percentiles near the singularity. SSC-ENO is also applied to a chemical model problem and a shock tube problem to study the impact of uncertainty both on the formation of discontinuities in time and on the location of discontinuities in space.

Witteveen, Jeroen A. S.; Iaccarino, Gianluca

2013-04-01

38

Kerr-type solution in Brans-Dicke theory

The Kerr-type solution in the Brans-Dicke theory should contain three parameters: a mass m, a rotational parameter a 0, and a coupling parameter ? It goes over to the Kerr solution in Einstein's theory of general relativity in the limit ? ? 8. Using these conditions, we construct a special solution from Bruckman's solutions which can be regarded as a Kerr-type solution in the Brans-Dicke theory.

Ma, Guang-Wen

1995-11-01

39

Weak omega-categories from intensional type theory

We show that for any type in Martin-L\\"of Intensional Type Theory, the terms of that type and its higher identity types form a weak omega-category in the sense of Leinster. Precisely, we construct a contractible globular operad P_{ML^Id} of definable "composition laws", and give an action of this operad on the terms of any type and its identity types.

Lumsdaine, Peter LeFanu

2008-01-01

40

Heterotic/Type-II duality and its field theory avatars

International Nuclear Information System (INIS)

In these lecture notes, I will describe heterotic/type-II duality in six and four dimensions. When supersymmetry is the maximal N=4 it will be shown that the duality reduces in the field theory limit to the Montonen-Olive duality of N=4 Super Yang-Mills theory. We will consider further compactifications of type II theory on Calabi-Yau manifolds. We will understand the physical meaning of geometric conifold singularities and the dynamics of conifold transitions. When the CY manifold is a K3 fibration we will argue that the type-II ground-state is dual to the heterotic theory compactified on K3xT2. This allows an exact computation of the low effective action. Taking the field theory limit, ?'?0, we will recover the Seiberg-Witten non-perturbative solution of N=2 gauge theory

41

Type IIB Flux Vacua from M-theory via F-theory

We study in detail some aspects of duality between type IIB and M-theory. We focus on the duality between type IIB string theory on K3 x T^2/Z_2 orientifold and M-theory on K3 x K3, in the F-theory limit. We give the explicit map between the fields and in particular between the moduli of compactification, studying their behavior under the F-theory limit. Turning on fluxes generates a potential for the moduli both in type IIB and in M-theory. We verify that the type IIB analysis gives the same results of the F-theory analysis. In particular, we check that the two potentials match.

Valandro, Roberto

2009-01-01

42

Revised theory of Pierce-type electron guns

International Nuclear Information System (INIS)

Attempts to date to obtain the shape of the beam forming electrodes of various Pierce-type electron guns are briefly discussed with emphasis on the many discrepansis in the results of previous works. A revised theory of Pierce-type electron guns is proposed. The shapes of the beam-forming electrodes for all known configurations of Pierce guns were computed on the basis of the proposed theory. (orig.)

43

Cold flow is a phenomenon occurring in drug-in-adhesive type of transdermal drug delivery systems (DIA-TDDS) because of the migration of DIA coat beyond the edge. Excessive cold flow can affect their therapeutic effectiveness, make removal of DIA-TDDS difficult from the pouch, and potentially decrease available dose if any drug remains adhered to pouch. There are no compendial or noncompendial methods available for quantification of this critical quality attribute. The objective was to develop a method for quantification of cold flow using stereomicroscopic imaging technique. Cold flow was induced by applying 1 kg force on punched-out samples of marketed estradiol DIA-TDDS (model product) stored at 25°C, 32°C, and 40°C/60% relative humidity (RH) for 1, 2, or 3 days. At the end of testing period, dimensional change in the area of DIA-TDDS samples was measured using image analysis software, and expressed as percent of cold flow. The percent of cold flow significantly decreased (p < 0.001) with increase in size of punched-out DIA-TDDS samples and increased (p < 0.001) with increase in cold flow induction temperature and time. This first ever report suggests that dimensional change in the area of punched-out samples stored at 32°C/60%RH for 2 days applied with 1 kg force could be used for quantification of cold flow in DIA-TDDS. PMID:24585397

Krishnaiah, Yellela S R; Katragadda, Usha; Khan, Mansoor A

2014-05-01

44

Vortex-type Half-BPS Solitons in ABJM Theory

We study Aharony-Bergman-Jafferis-Maldacena (ABJM) theory without and with mass deformation. It is shown that maximally supersymmetry preserving, D-term, and F-term mass deformations of single mass parameter are equivalent. We obtain vortex-type half-BPS equations and the corresponding energy bound. For the undeformed ABJM theory, the resulting half-BPS equation is the same as that in supersymmetric Yang-Mills theory and no finite energy regular BPS solution is found. For the mass-deformed ABJM theory, the half-BPS equations for U(2)xU(2) case reduce to the vortex equation in Maxwell-Higgs theory, which supports static regular multi-vortex solutions. In U(N)xU(N) case with N>2 the nonabelian vortex equation of Yang-Mills-Higgs theory is obtained.

Kim, Chanju; Kwon, O-Kab; Nakajima, Hiroaki

2009-01-01

45

Axion Inflation in Type II String Theory

Inflationary models driven by a large number of axion fields are discussed in the context of type IIB compactifications with N=1 supersymmetry. The inflatons arise as the scalar modes of the R-R two-forms evaluated on vanishing two-cycles in the compact geometry. The vanishing cycles are resolved by small two-volumes or NS-NS B-fields which sit together with the inflatons in the same supermultiplets. String world-sheets wrapping the vanishing cycles correct the metric of the R-R inflatons. They can help to generate kinetic terms close to the Planck scale and a mass hierarchy between the axions and their non-axionic partners during inflation. At small string coupling, D-brane corrections are subleading in the metric of the R-R inflatons. However, an axion potential can be generated by D1 instantons or gaugino condensates on D5 branes. Models with sufficiently large number of axions admit regions of chaotic inflation which can stretch over the whole axion field range for potentials from gaugino condensates. The...

Grimm, Thomas W

2007-01-01

46

Inflationary constraints on type IIA string theory

International Nuclear Information System (INIS)

We prove that inflation is forbidden in the most well understood class of semi-realistic type IIA string compactifications: Calabi-Yau compactifications with only standard NS-NS 3-form flux, R-R fluxes, D6-branes and O6-planes at large volume and small string coupling. With these ingredients, the first slow-roll parameter satisfies ? ? 27/13 whenever V>0, ruling out both inflation (including brane/anti-brane inflation) and de Sitter vacua in this limit. Our proof is based on the dependence of the 4-dimensional potential on the volume and dilaton moduli in the presence of fluxes and branes. We also describe broader classes of IIA models which may include cosmologies with inflation and/or de Sitter vacua. The inclusion of extra ingredients, such as NS 5-branes and geometric or non-geometric NS-NS fluxes, evades the assumptions used in deriving the no-go theorem. We focus on NS 5-branes and outline how such ingredients may prove fruitful for cosmology, but we do not provide an explicit model. We contrast the results of our IIA analysis with the rather different situation in IIB

47

Introduction to type-2 fuzzy logic control theory and applications

Written by world-class leaders in type-2 fuzzy logic control, this book offers a self-contained reference for both researchers and students. The coverage provides both background and an extensive literature survey on fuzzy logic and related type-2 fuzzy control. It also includes research questions, experiment and simulation results, and downloadable computer programs on an associated website. This key resource will prove useful to students and engineers wanting to learn type-2 fuzzy control theory and its applications.

Mendel, Jerry M; Tan, Woei-Wan; Melek, William W; Ying, Hao

2014-01-01

48

M-theory and Type IIA Flux Compactifications

We consider compactifications of M-theory and type IIA string theory to four dimensions. For Minkowski space-time, a supergravity no-go theorem forbids flux supported in the internal space. We show how to evade this no-go theorem by exhibiting new sources of brane charge: in string theory, the basic physical phenomenon is the generation of new brane charges from D-branes in transverse fluxes. In M-theory, there is a new source of M5-brane charge from novel higher derivative couplings that involve fluxes as well as curvatures. We present some explicit orientifold examples with both N=1 and N=2 space-time supersymmetry. Finally, we explain the status of massive type IIA flux compactifications.

McOrist, Jock

2012-01-01

49

Dyon Spectrum in N=4 Supersymmetric Type II String Theories

Digital Repository Infrastructure Vision for European Research (DRIVER)

We compute the spectrum of quarter BPS dyons in freely acting Z_2 and Z_3 orbifolds of type II string theory compactified on a six dimensional torus. For large charges the result for statistical entropy computed from the degeneracy formula agrees with the corresponding black hole entropy to first non-leading order after taking into account corrections due to the curvature squared terms in the effective action. The result is significant since in these theories the entropy of ...

David, Justin R.; Jatkar, Dileep P.; Sen, Ashoke

2006-01-01

50

The Superconformal Index of Class S Theories of Type D

We consider the superconformal index of class S theories of type D, which arise by compactification of the (2,0) D_n theories on a punctured Riemann surface C. We also allow for the presence of twist lines on C associated to the Z_2 outer automorphism of D_n. For a two-parameter slice (p=0, q, t) in the space of superconformal fugacities, we determine the 2d TQFT that computes the index.

Lemos, Madalena; Rastelli, Leonardo

2012-01-01

51

Intensional Type Theory with Guarded Recursive Types qua Fixed Points on Universes

DEFF Research Database (Denmark)

Guarded recursive functions and types are useful for giving semantics to advanced programming languages and for higher-order programming with infinite data types, such as streams, e.g., for modeling reactive systems. We propose an extension of intensional type theory with rules for forming fixed points of guarded recursive functions. Guarded recursive types can be formed simply by taking fixed points of guarded recursive functions on the universe of types. Moreover, we present a general model construction for constructing models of the intensional type theory with guarded recursive functions and types. When applied to the groupoid model of intensional type theory with the universe of small discrete groupoids, the construction gives a model of guarded recursion for which there is a one-to-one correspondence between fixed points of functions on the universe of types and fixed points of (suitable) operators on types. In particular, we find that the functor category Grpd?op from the preordered set of natural numbers to the category of groupoids is a model of intensional type theory with guarded recursive types.

Birkedal, Lars; Mogelberg, R.E.

2013-01-01

52

Intensional type theory with guarded recursive types qua fixed points on universes

DEFF Research Database (Denmark)

Guarded recursive functions and types are useful for giving semantics to advanced programming languages and for higher-order programming with infinite data types, such as streams, e.g., for modeling reactive systems. We propose an extension of intensional type theory with rules for forming fixed points of guarded recursive functions. Guarded recursive types can be formed simply by taking fixed points of guarded recursive functions on the universe of types. Moreover, we present a general model construction for constructing models of the intensional type theory with guarded recursive functions and types. When applied to the groupoid model of intensional type theory with the universe of small discrete groupoids, the construction gives a model of guarded recursion for which there is a one-to-one correspondence between fixed points of functions on the universe of types and fixed points of (suitable) operators on types. In particular, we find that the functor category from the preordered set of natural numbers to the category of groupoids is a model of intensional type theory with guarded recursive types.

MØgelberg, Rasmus Ejlers; Birkedal, Lars

2013-01-01

53

Models of Particle Physics from Type IIB String Theory and F-theory: A Review

We review particle physics model building in type IIB string theory and F-theory. This is a region in the landscape where in principle many of the key ingredients required for a realistic model of particle physics can be combined successfully. We begin by reviewing moduli stabilisation within this framework and its implications for supersymmetry breaking. We then review model building tools and developments in the weakly coupled type IIB limit, for both local D3-branes at singularities and global models of intersecting D7-branes. Much of recent model building work has been in the strongly coupled regime of F-theory due to the presence of exceptional symmetries which allow for the construction of phenomenologically appealing Grand Unified Theories. We review both local and global F-theory model building starting from the fundamental concepts and tools regarding how the gauge group, matter sector and operators arise, and ranging to detailed phenomenological properties explored in the literature.

Maharana, Anshuman

2012-01-01

54

The Fayet-Iliopoulos term in Type-I string theory and M-theory

The magnitude of the Fayet-Iliopoulos term is calculated for compactifications of Type-I string theory and Horava-Witten M-theory in which there exists a pseudo-anomalous U(1)_X. Contrary to various conjectures, it is found that in leading order in the perturbative expansion around the weakly-coupled M-theory or Type-I limits, a result identical to that of the weakly-coupled E_8xE_8 heterotic string is obtained. The result is independent of the values chosen for the Type-I string scale or the size of the M-theory 11th dimension, only depending upon Newton's constant and the unified gauge coupling.

March-Russell, John David

1998-01-01

55

Multivariate Bonferroni-type inequalities theory and applications

Multivariate Bonferroni-Type Inequalities: Theory and Applications presents a systematic account of research discoveries on multivariate Bonferroni-type inequalities published in the past decade. The emergence of new bounding approaches pushes the conventional definitions of optimal inequalities and demands new insights into linear and Fréchet optimality. The book explores these advances in bounding techniques with corresponding innovative applications. It presents the method of linear programming for multivariate bounds, multivariate hybrid bounds, sub-Markovian bounds, and bounds using Hamil

Chen, John

2014-01-01

56

Massive type IIA string theory cannot be strongly coupled

Understanding the strong coupling limit of massive type IIA string theory is a longstanding problem. We argue that perhaps this problem does not exist; namely, there may be no strongly coupled solutions of the massive theory. We show explicitly that massive type IIA string theory can never be strongly coupled in a weakly curved region of space-time. We illustrate our general claim with two classes of massive solutions in AdS4xCP3: one, previously known, with N = 1 supersymmetry, and a new one with N = 2 supersymmetry. Both solutions are dual to d = 3 Chern-Simons-matter theories. In both these massive examples, as the rank N of the gauge group is increased, the dilaton initially increases in the same way as in the corresponding massless case; before it can reach the M-theory regime, however, it enters a second regime, in which the dilaton decreases even as N increases. In the N = 2 case, we find supersymmetry-preserving gauge-invariant monopole operators whose mass is independent of N. This predicts the exist...

Aharony, Ofer; Tomasiello, Alessandro; Zaffaroni, Alberto

2010-01-01

57

Constructive Type Theory and the Dialogical Approach to Meaning

Directory of Open Access Journals (Sweden)

Full Text Available In its origins Dialogical logic constituted one part of a new movement called the Erlangen School or Erlangen Constructivism. Its goal was to provide a new start to a general theory of language and of science. According to the Erlangen-School, language is not just a fact that we discover, but a human cultural accomplishment whose construction reason can and should control. The resulting project of intentionally constructing a scientific language was called the Orthosprache-project. Unfortunately, the Orthosprache-project was not further developed and seemed to fade away. It is possible that one of the reasons for this fading away is that the link between dialogical logic and Orthosprache was not sufficiently developed - in particular, the new theory of meaning to be found in dialogical logic seemed to be cut off from both the project of establishing the basis for scientific language and also from a general theory of meaning. We would like to contribute to clarifying one possible way in which a general dialogical theory of meaning could be linked to dialogical logic. The idea behind the proposal is to make use of constructive type theory in which logical inferences are preceded by the description of a fully interpreted language. The latter, we think, provides the means for a new start not only for the project of Orthosprache, but also for a general dialogical theory of meaning.

Shahid Rahman

2013-12-01

58

Dyon spectrum in N = 4 supersymmetric type II string theories

Energy Technology Data Exchange (ETDEWEB)

We compute the spectrum of quarter BPS dyons in freely acting Z{sub 2} and Z{sub 3} orbifolds of type II string theory compactified on a six dimensional torus. For large charges the result for statistical entropy computed from the degeneracy formula agrees with the corresponding black hole entropy to first non-leading order after taking into account corrections due to the curvature squared terms in the effective action. The result is significant since in these theories the entropy of a small black hole, computed using the curvature squared corrections to the effective action, fails to reproduce the statistical entropy associated with elementary string states.

David, Justin R.; Jatkar, Dileep P.; Sen, Ashoke [Harish-Chandra Research Institute, Chhatnag Road, Jhusi, Allahabad 211019 (India)

2006-11-15

59

A theory of solar type III radio bursts

International Nuclear Information System (INIS)

A theory of type III bursts is reviewed. Energetic electrons propagating through the interplanetary medium are shown to excite the one dimensional oscillating two stream instability (OTSI). The OTSI is in turn stabilized by anomalous resistivity which completes the transfer of long wavelength Langmuir waves to short wavelengths, out of resonance with the electrons. The theory explains the small energy losses suffered by the electrons in propagating to 1 AU, the predominance of second harmonic radiation, and the observed correlation between radio and electron fluxes. (Auth.)

60

D-branes and KK-theory in Type I String Theory

We analyse unstable D-brane systems in type I string theory. Generalizing the proposal in hep-th/0108085, we give a physical interpretation for real KK-theory and claim that the D-branes embedded in a product space X x Y which are made from the unstable Dp-brane system wrapped on Y are classified by a real KK-theory group KKO^{p-1}(X,Y). The field contents of the unstable D-brane systems are systematically described by a hidden Clifford algebra structure. We also investigate the matrix theory based on non-BPS D-instantons and show that the spectrum of D-branes in the theory is exactly what we expect in type I string theory, including stable non-BPS D-branes with Z_2 charge. We explicitly construct the D-brane solutions in the framework of BSFT and analyse the physical property making use of the Clifford algebra.

Asakawa, T; Terashima, S

2002-01-01

61

D-branes and KK-theory in type I string theory

International Nuclear Information System (INIS)

We analyse unstable D-brane systems in type-I string theory. Generalizing the proposal in hep-th/0108085, we give a physical interpretation for real KK-theory and claim that the D-branes embedded in a product space XxY which are made from the unstable Dp-brane system wrapped on Y are classified by a real KK-theory group KKOp-1(X,Y). The field contents of the unstable D-brane systems are systematically described by a hidden Clifford algebra structure.We also investigate the matrix theory based on non-BPS D-instantons and show that the spectrum of D-branes in the theory is exactly what we expect in type-I string theory, including stable non-BPS D-branes with Z2 charge. We explicitly construct the D-brane solutions in the framework of BSFT and analyse the physical property making use of the Clifford algebra. (author)

62

Irregular singularities in Liouville theory and Argyres-Douglas type gauge theories, I

Energy Technology Data Exchange (ETDEWEB)

Motivated by problems arising in the study of N=2 supersymmetric gauge theories we introduce and study irregular singularities in two-dimensional conformal field theory, here Liouville theory. Irregular singularities are associated to representations of the Virasoro algebra in which a subset of the annihilation part of the algebra act diagonally. In this paper we define natural bases for the space of conformal blocks in the presence of irregular singularities, describe how to calculate their series expansions, and how such conformal blocks can be constructed by some delicate limiting procedure from ordinary conformal blocks. This leads us to a proposal for the structure functions appearing in the decomposition of physical correlation functions with irregular singularities into conformal blocks. Taken together, we get a precise prediction for the partition functions of some Argyres-Douglas type theories on S{sup 4}. (orig.)

Gaiotto, D. [Institute for Advanced Study (IAS), Princeton, NJ (United States); Teschner, J. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2012-03-15

63

Irregular singularities in Liouville theory and Argyres-Douglas type gauge theories, I

International Nuclear Information System (INIS)

Motivated by problems arising in the study of N=2 supersymmetric gauge theories we introduce and study irregular singularities in two-dimensional conformal field theory, here Liouville theory. Irregular singularities are associated to representations of the Virasoro algebra in which a subset of the annihilation part of the algebra act diagonally. In this paper we define natural bases for the space of conformal blocks in the presence of irregular singularities, describe how to calculate their series expansions, and how such conformal blocks can be constructed by some delicate limiting procedure from ordinary conformal blocks. This leads us to a proposal for the structure functions appearing in the decomposition of physical correlation functions with irregular singularities into conformal blocks. Taken together, we get a precise prediction for the partition functions of some Argyres-Douglas type theories on S4. (orig.)

64

DEFF Research Database (Denmark)

Structure model type and trabecular thickness are important characteristics in describing cancellous bone architecture. It has been qualitatively observed that a radical change of trabeculae from plate-like to rod-like occurs in aging, bone remodeling, and osteoporosis. Thickness of trabeculae has traditionally been measured using model-based histomorphometric methods on two-dimensional (2-D) sections. However, no quantitative study has been published based on three-dimensional (3-D) methods on the age-related changes in structure model type and trabecular thickness for human peripheral (tibial) cancellous bone. In this study, 160 human proximal tibial cancellous bone specimens from 40 normal donors, aged 16 to 85 years, were collected. These specimens were micro-computed tomography (micro-CT) scanned, then the micro-CT images were segmented using optimal thresholds. From accurate 3-D data sets, structure model type and trabecular thickness were quantified by means of novel 3-D methods. Structure model type was assessed by calculating the structure model index (SMI). The SMI was quantified based on a differential analysis of the triangulated bone surface of a structure. This technique allows quantification of structure model type, such as plate, rod objects, or mixture of plates or rods. Trabecular thickness is calculated directly from 3-D images, which is especially important for an a priori unknown or changing structure. Furthermore, 2-D trabecular thickness was also calculated based on the plate model. Our results showed that structure model type changed towards more rod-like in the elderly, and that trabecular thickness declined significantly with age. These changes become significant after 80 years of age for human tibial cancellous bone, whereas both properties seem to remain relatively unchanged between 20 and 80 years. Although a fairly close relationship was seen between 3-D trabecular thickness and 2-D trabecular thickness, real 3-D trabecular thickness was significantly underestimated using 2-D method.

Ding, Ming; Hvid, I

2000-01-01

65

Energy Technology Data Exchange (ETDEWEB)

As a destructive quantification method of {sup 3}H in low and intermediate level radwastes, bomb oxidation, sample oxidation, and wet oxidation methods have been introduced. These methods have some merits and demerits in the radiochemical separation of {sup 3}H radionuclides. That is, since the bomb oxidation and sample oxidation methods are techniques using heating at high temperature, the separation methods of the radionuclides are relatively simple. However, since {sup 3}H radionuclide has a property of being diffused deeply into the inside of metals, {sup 3}H which is distributed on the surface of the metals can only be extracted if the methods are applied. As an another separation method, the wet oxidation method makes {sup 3}H oxidized with an acidic solution, and extracted completely to an oxidized HTO compound. However, incomplete oxidized {sup 3}H compounds, which are produced by reactions of acidic solutions and metallic radwastes, can be released into the air. Thus, in this study, a wet oxidation method to extract and quantify the {sup 3}H radionuclide from metallic radwastes was established. In particular, a complete extraction method and complete oxidation method of incomplete chemical compounds of {sup 3}H using a Pt catalyst were studied. The radioactivity of {sup 3}H in metallic radwastes is extracted and measured using a wet oxidation method and liquid scintillation counter. Considering the surface dose rate of the sample, the appropriate size of the sample was determined and weighed, and a mixture of oxidants was added to a 200 ml round flask with 3 tubes. The flask was quickly connected to the distilling apparatus. 20 mL of 16 wt% H{sub 2}SO{sub 4} was given into the 200-ml round flask through a dropping funnel while under stirring and refluxing. After dropping, the temperature of the mixture was raised to 96 deg. C and the sample was leached and oxidized by refluxing for 3 hours. At that time, the incomplete oxidized {sup 3}H compounds were completely oxidized using the Pt catalysts and produced a stable HTO compound. After that, about a 20 ml solution was distilled in the separation apparatus, and the distillate was mixed with an ultimagold LLT as a cocktail solution. The solution in the vial was left standing for at least 24 hours. The radioactivity of {sup 3}H was counted directly using a liquid scintillation analyzer (Packard, 2500 TR/AB, Alpha and Beta Liquid Scintillation Analyzer). (authors)

Ahn, H.J.; Choi, K.C.; Choi, K.S.; Park, T.H.; Park, Y.J.; Song, K. [Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon, 305-330 (Korea, Republic of)

2013-07-01

66

Quantum Bianchi Type IX Cosmology in K-Essence Theory

We use one of the simplest forms of the K-essence theory and apply it to the anisotropic Bianchi type IX cosmological model, with a barotropic perfect fluid modeling the usual matter content. We show that the most important contribution of the scalar field occurs during a stiff matter phase. Also, we present a canonical quantization procedure of the theory which can be simplified by reinterpreting the scalar field as an exotic part of the total matter content. The solutions to the Wheeler-DeWitt equation were found using the Bohmian formulation Bohm (Phys. Rev. 85(2):166, 1952) of quantum mechanics, employing the amplitude-real-phase approach Moncrief and Ryan (Phys. Rev. D 44:2375, 1991), where the ansatz for the wave function is of the form ?( ? ? )= ?( ?) W( ? ? ), where S is the superpotential function, which plays an important role in solving the Hamilton-Jacobi equation.

Espinoza-García, Abraham; Socorro, J.; Pimentel, Luis O.

2014-09-01

67

A Modular Type-checking algorithm for Type Theory with Singleton Types and Proof Irrelevance

We define a logical framework with singleton types and one universe of small types. We give the semantics using a PER model; it is used for constructing a normalisation-by-evaluation algorithm. We prove completeness and soundness of the algorithm; and get as a corollary the injectivity of type constructors. Then we give the definition of a correct and complete type-checking algorithm for terms in normal form. We extend the results to proof-irrelevant propositions.

Abel, Andreas; Pagano, Miguel

2011-01-01

68

In situ fluid typing and quantification with 1D and 2D NMR logging.

In situ nuclear magnetic resonance (NMR) fluid typing has recently gained momentum due to data acquisition and inversion algorithm enhancement of NMR logging tools. T(2) distributions derived from NMR logging contain information on bulk fluids and pore size distributions. However, the accuracy of fluid typing is greatly overshadowed by the overlap between T(2) peaks arising from different fluids with similar apparent T(2) relaxation times. Nevertheless, the shapes of T(2) distributions from different fluid components are often different and can be predetermined. Inversion with predetermined T(2) distributions allows us to perform fluid component decomposition to yield individual fluid volume ratios. Another effective method for in situ fluid typing is two-dimensional (2D) NMR logging, which results in proton population distribution as a function of T(2) relaxation time and fluid diffusion coefficient (or T(1) relaxation time). Since diffusion coefficients (or T(1) relaxation time) for different fluid components can be very different, it is relatively easy to separate oil (especially heavy oil) from water signal in a 2D NMR map and to perform accurate fluid typing. Combining NMR logging with resistivity and/or neutron/density logs provides a third method for in situ fluid typing. We shall describe these techniques with field examples. PMID:17466778

Sun, Boqin

2007-05-01

69

Phosphorus is an important natural nutrient, but high dietary phosphorus intake, including that sourced from added preservatives, is of great concern in renal patients. In this context a reliable analytical method able to quantify differential phosphorus in food could be a valuable tool for monitoring diet composition This paper presents a novel analytical procedure to quantify the following kinds of phosphorus in cooked ham: total (TP), inorganic (IP), from phospholipids (PL), and from phosphoproteins (PP). This technique is based on a suitable sample preparation followed by spectrophotometric analyses. Analytical performances of each method were evaluated, taking advantage also of food industry certified material and in-house reference samples. Limit of detection and limit of quantification values for TP, IP, PP-derived, and PL-derived phosphorus were 13 and 37, 11 and 33, 2 and 20, and 6 and 16 mg P/100 g fresh mass, respectively. Similar results were obtained when this procedure was used to quantify different types of phosphorus present in cooked ham samples. In conclusion, this procedure is effective for quantifying the content of different types of phosphorus present in cooked ham, which can be contributed by different phosphorus-containing ingredients and additives. To the best of the authors' knowledge, this is the first time that simultaneous determination of TP, IP, PL, and PP in cooked ham has been reported. PMID:24437945

Benini, Omar; Saba, Alessandro; Ferretti, Valerio; Gianfaldoni, Daniela; Kalantar-Zadeh, Kamyar; Cupisti, Adamasco

2014-02-12

70

Alzheimer's disease (AD) is the most common form of dementia in the elderly characterized by extracellular deposition of amyloid plaques (AP). Using animal models, AP loads have been manually measured from histological specimens to understand disease etiology, as well as response to treatment. Due to the manual nature of these approaches, obtaining the AP load is labourious, subjective and error prone. Automated algorithms can be designed to alleviate these challenges by objectively segmenting AP. In this paper, we focus on the development of a novel algorithm for AP segmentation based on robust preprocessing and a Type II fuzzy system. Type II fuzzy systems are much more advantageous over the traditional Type I fuzzy systems, since ambiguity in the membership function may be modeled and exploited to generate excellent segmentation results. The ambiguity in the membership function is defined as an adaptively changing parameter that is tuned based on the local contrast characteristics of the image. Using transgenic mouse brains with AP ground truth, validation studies were carried out showing a high degree of overlap and low degree of oversegmentation (0.8233 and 0.0917, respectively). The results highlight that such a framework is able to handle plaques of various types (diffuse, punctate), plaques with varying A? concentrations as well as intensity variation caused by treatment effects or staining variability.

Khademi, April; Hosseinzadeh, Danoush

2014-03-01

71

THE TOTAL DNA QUANTIFICATION FOR THREE TYPES OF TISSUE FROM CARASSIUS AURATUS GIBELIO BLOCH

Directory of Open Access Journals (Sweden)

Full Text Available We established the total DNA quantity and the variability intervals for three types of tissue (muscle, liver and spleen from five individuals of Carassius auratus gibelio Bloch, to characterize this species from the point of view of this parameter.

Zenovia Olteanu

2005-08-01

72

The hexagon gauge anomaly in Type 1 superstring theory

International Nuclear Information System (INIS)

Hexagon diagrams with external on-mass-shell Yang-Mills gauge particles are investigated in Type I superstring theory. Both the annulus and the Mobius-strip diagrams are shown to give anomalies, implying that spurious longitudinal modes cannot be consistently decoupled. However, the anomalies cancel when the two diagrams are added together if the gauge group is chosen to be SO(32). In carrying out the analysis, two different regulators are considered, but the same conclusions emerge in both cases. The authors point out where various terms in the low-energy effective action originate in superstring diagrams

73

Flux vacua in DBI type Einstein-Maxwell theory

We study compactification of extra dimensions in a theory of Dirac-Born-Infeld type gravity. We investigate the solution for Minkowski spacetime with an S 2 extra space as well as that for de Sitter spacetime ( S 4) with an S 2 extra space. They are derived by the effective potential method in the presence of the magnetic flux on the extra sphere. We also consider the higher-dimensional generalization of the solutions. We find that, in a certain model, the radius of the extra space has a minimum value independent of the higher-dimensional Newton constant.

Maki, Takuya; Kan, Nahomi; Kobayashi, Koichiro; Shiraishi, Kiyoshi

2012-10-01

74

Flux vacua in DBI type Einstein-Maxwell theory

We study compactification of extra dimensions in a theory of Dirac-Born-Infeld (DBI) type gravity. We investigate the solution for Minkowski spacetime with an $S^2$ extra space as well as that for de Sitter spacetime ($S^4$) with an $S^2$ extra space. They are derived by the efective potential method in the presence of the magnetic flux on the extra sphere. We also consider the higher dimensional generalization of the solutions. We find that, in a certain model, the radius of the extra space has a minimum value independent of the higher-dimensional Newton constant in weak-field limit.

Maki, Takuya; Kobayashi, Koichiro; Shiraishi, Kiyoshi

2011-01-01

75

Type II Superstring Field Theory: Geometric Approach and Operadic Description

We outline the construction of type II superstring field theory leading to a geometric and algebraic BV master equation, analogous to Zwiebach's construction for the bosonic string. The construction uses the small Hilbert space. Elementary vertices of the non-polynomial action are described with the help of a properly formulated minimal area problem. They give rise to an infinite tower of superstring field products defining a $\\mathcal{N}=1$ generalization of a loop homotopy Lie algebra, the genus zero part generalizing a homotopy Lie algebra. Finally, we give an operadic interpretation of the construction.

Jurco, Branislav

2013-01-01

76

Species-independent bioassay for sensitive quantification of antiviral type I interferons

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Studies of the host response to infection often require quantitative measurement of the antiviral type I interferons (IFN-?/?) in biological samples. The amount of IFN is either determined via its ability to suppress a sensitive indicator virus, by an IFN-responding reporter cell line, or by ELISA. These assays however are either time-consuming and lack convenient readouts, or they are rather insensitive and restricted to IFN from a particular host speci...

2010-01-01

77

U-dualities in Type II string theories and M-theory

In this thesis the recently developed duality covariant approach to string and M-theory is investigated. In this formalism the U-duality symmetry of M-theory or T-duality symmetry of Type II string theory becomes manifest upon extending coordinates that describe a background. The effective potential of Double Field Theory is formulated only up to a boundary term and thus does not capture possible topological effects that may come from a boundary. By introducing a generalised normal we derive a manifestly duality covariant boundary term that reproduces the known Gibbons-Hawking action of General Relativity, if the section condition is imposed. It is shown that the full potential can be represented as a sum of the scalar potential of gauged supergravity and a topological term that is a full derivative. The latter is conjectured to capture non-trivial topological information of the corresponding background, such as monodromy around an exotic brane. Next we show that the Scherk-Schwarz reduction of M-theory exten...

Musaev, Edvard

2013-01-01

78

A Co-Operative Phenomena Type Local Realistic Theory

We analyze a conceivable type of local realistic theory, which we call a co-operative phenomena type local realistic theory. In an experimental apparatus to measure second or fourth order interference effects, it images that their exists a stable global pattern or mode in a hypothesized medium that is at least the size of the coherence volume of all the involved beams. If you change the position of a mirror, beam splitter, polarizer, state preparation, or block a beam then a new and different stable global state is entered very quickly. In an interferometer a photon passes only one arm of the apparatus but knows if the other arm is open or closed since the global pattern through which it travels through contains this information and guides it appropriately. In a polarization correlation experiment, two distant polarizers are part of the same global pattern or state which is very rapidly determined by the whole apparatus. It is experimentally testable. The situation in relationship to the special relativity is...

Buonomano, V

1999-01-01

79

Type IIB flux vacua from G-theory I

We construct non-perturbatively exact four-dimensional Minkowski vacua of type IIB string theory with non-trivial fluxes. These solutions are found by gluing together, consistently with U-duality, local solutions of type IIB supergravity on $T^4 \\times \\mathbb{C}$ with the metric, dilaton and flux potentials varying along $\\mathbb{C}$ and the flux potentials oriented along $T^4$. We focus on solutions locally related via U-duality to non-compact Ricci-flat geometries. More general solutions and a complete analysis of the supersymmetry equations are presented in the companion paper [1]. We build a precise dictionary between fluxes in the global solutions and the geometry of an auxiliary $K3$ surface fibered over $\\mathbb{CP}^1$. In the spirit of F-theory, the flux potentials are expressed in terms of locally holomorphic functions that parametrize the complex structure moduli space of the $K3$ fiber in the auxiliary geometry. The brane content is inferred from the monodromy data around the degeneration points o...

Candelas, Philip; Damian, Cesar; Larfors, Magdalena; Morales, Jose Francisco

2014-01-01

80

Threshold anomalies in Horava-Lifshitz-type theories

International Nuclear Information System (INIS)

Recently the study of threshold kinematic requirements for particle-production processes has played a very significant role in the phenomenology of theories with departures from Poincare symmetry. We here specialize these threshold studies to the case of a class of violations of Poincare symmetry which has been much discussed in the literature on Horava-Lifshitz scenarios. These involve modifications of the energy-momentum ('dispersion') relation that may be different for different types of particles, but always involve even powers of energy-momentum in the correction terms. We establish the requirements for compatibility with the observed cosmic-ray spectrum, which is sensitive to the photopion-production threshold. We find that the implications for the electron-positron pair-production threshold are rather intriguing, in light of some recent studies of TeV emissions by Blazars. Our findings should also provide additional motivation for examining the fate of the law of energy-momentum conservation in Horava-Lifshitz-type theories.

81

Real-time quantification of wild-type contaminants in glyphosate tolerant soybean

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Trait purity is a key factor for the successful utilization of biotech varieties and is currently assessed by analysis of individual seeds or plants. Here we propose a novel PCR-based approach to test trait purity that can be applied to bulk samples. To this aim the insertion site of a transgene is characterized and the corresponding sequence of the wild-type (wt allele is used as diagnostic target for amplification. As a demonstration, we developed a real-time quantitative PCR method to test purity of glyphosate tolerant (Roundup Ready®, RR soybean. Results The soybean wt sequence at the RR locus was characterized and found to be highly conserved among conventional genotypes, thus allowing the detection of possibly any soybean non-trait contaminant. On the other hand, no amplification product was obtained from RR soybean varieties, indicating that the wt sequence is single copy and represents a suitable marker of conventional soybean presence. In addition, results obtained from the analysis of wt-spiked RR samples demonstrate that it is possible to use the real-time PCR assay to quantify the non-trait contamination with an acceptable degree of accuracy. Conclusion In principle this approach could be successfully applied to any transgenic event, provided that the wild-type sequence is conserved and single copy. The main advantages of the assay here described derive from its applicability to bulk samples, which would allow to increase the number of single seeds or plants forming the analytical sample, thus improving accuracy and throughput while containing costs. For these reasons this application of quantitative PCR could represent a useful tool in agricultural biotechnology.

Noli Enrico

2009-03-01

82

Geometry of model building in type IIB superstring theory and F-theory compactifications

International Nuclear Information System (INIS)

The present thesis is devoted to the study and geometrical description of type IIB superstring theory and F-theory model building. After a concise exposition of the basic concepts of type IIB flux compactifications, we explain their relation to F-theory. Moreover, we give a brief introduction to toric geometry focusing on the construction and the analysis of compact Calabi-Yau (CY) manifolds, which play a prominent role in the compactification of extra spatial dimensions. We study the 'Large Volume Scenario' on explicit new compact four-modulus CY manifolds. We thoroughly analyze the possibility of generating neutral non-perturbative superpotentials from Euclidean D3-branes in the presence of chirally intersecting D7-branes. We find that taking proper account of the Freed-Witten anomaly on non-spin cycles and of the Kaehler cone conditions imposes severe constraints on the models. Furthermore, we systematically construct a large number of compact CY fourfolds that are suitable for F-theory model building. These elliptically fibered CYs are complete intersections of two hypersurfaces in a six-dimensional ambient space. We first construct three-dimensional base manifolds that are hypersurfaces in a toric ambient space. We find that elementary conditions, which are motivated by F-theory GUTs (Grand Unified Theory), lead to strong constraints on the geometry, which significantly reduce the number of suitable models. We work out several examples in more detail. At the end,veral examples in more detail. At the end, we focus on the complex moduli space of CY threefolds. It is a known result that infinite sequences of type IIB flux vacua with imaginary self-dual flux can only occur in so-called D-limits, corresponding to singular points in complex structure moduli space. We refine this no-go theorem by demonstrating that there are no infinite sequences accumulating to the large complex structure point of a certain class of one-parameter CY manifolds. We perform a similar analysis for conifold points and for the decoupling limit, obtaining identical results. Furthermore, we establish the absence of infinite sequences in a D-limit corresponding to the large complex structure limit of a two-parameter CY. We corroborate our results with a numerical study ofthe sequences. (author)

83

International Nuclear Information System (INIS)

Five Type 304L stainless steel specimens were subjected to incrementally increasing values of plastic strain. At each value of strain, the associated static stress was recorded and the specimen was subjected to positron annihilation spectroscopy (PAS) using the Doppler Broadening method. A calibration curve for the 'S' parameter as a function of stress was developed based on the five specimens. Seven different specimens (blind specimens labeled B1-B7) of 304L stainless steel were subjected to values of stress inducing plastic deformation. The values of stress ranged from 310 to 517 MPa. The seven specimens were subjected to PAS post-loading using the Doppler Broadening method, and the results were compared against the developed curve from the previous five specimens. It was found that a strong correlation exists between the 'S' parameter, stress, and strain up to a strain value of 15%, corresponding to a stress value of 500 MPa, beyond which saturation of the 'S' parameter occurs. Research Highlights: ? Specimens were initially in an annealed/recrystallized condition. ? Calibration results indicate positron annihilation measurements yield correlation. ? Deformation produced by cold work was likely larger than the maximum strain.

84

Almost Special Holonomy in Type IIA&M Theory

We consider spaces M_7 and M_8 of G_2 holonomy and Spin(7) holonomy in seven and eight dimensions, with a U(1) isometry. For metrics where the length of the associated circle is everywhere finite and non-zero, one can perform a Kaluza-Klein reduction of supersymmetric M-theory solutions (Minkowksi)_4\\times M_7 or (Minkowksi)_3\\times M_8, to give supersymmetric solutions (Minkowksi)_4\\times Y_6 or (Minkowksi)_3\\times Y_7 in type IIA string theory with a non-singular dilaton. We study the associated six-dimensional and seven-dimensional spaces Y_6 and Y_7 perturbatively in the regime where the string coupling is weak but still non-zero, for which the metrics remain Ricci-flat but that they no longer have special holonomy, at the linearised level. In fact they have ``almost special holonomy,'' which for the case of Y_6 means almost Kahler, together with a further condition. For Y_7 we are led to introduce the notion of an ``almost G_2 manifold,'' for which the associative 3-form is closed but not co-closed. We o...

Cvetic, M; Lü, H; Pope, C N

2002-01-01

85

On axionic dark matter in Type IIA string theory

We investigate viable scenarios with various axions in the context of supersymmetric field theory and in globally consistent D-brane models. The Peccei-Quinn symmetry is associated with an anomalous U(1) symmetry, which acquires mass at the string scale but remains as a perturbative global symmetry at low energies. The origin of the scalar Higgs-axion potential from F-, D- and soft breaking terms is derived, and two Standard Model examples of global intersecting D6-brane models in Type II orientifolds are presented, which differ in the realisation of the Higgs sector and in the hidden sector, the latter of which is of particluar importance for the soft supersymmetry breaking terms.

Honecker, Gabriele

2014-01-01

86

Classical Bianchi type I cosmology in K-essence theory

We use one of the simplest forms of the K-essence theory and we apply it to the classical anisotropic Bianchi type I cosmological model, with a barotropic perfect fluid modeling the usual matter content and with cosmological constant. The classical solutions for any but the stiff fluid and without cosmological constant are found in closed form, using a time transformation. We also present the solution whith cosmological constant and some particular values of the barotropic parameter. We present the possible isotropization of the cosmological model, using the ratio between the anisotropic parameters and the volume of the universe and show that this tend to a constant or to zero for different cases. We include also a qualitative analysis of the analog of the Friedmann equation.

Socorro, J; Espinoza-García, Abraham

2014-01-01

87

Type IIB flux vacua from G-theory II

We find analytic solutions of type IIB supergravity on geometries that locally take the form $\\text{Mink}\\times M_4\\times \\mathbb{C}$ with $M_4$ a generalised complex manifold. The solutions involve the metric, the dilaton, NSNS and RR flux potentials (oriented along the $M_4$) parametrised by functions varying only over $\\mathbb{C}$. Under this assumption, the supersymmetry equations are solved using the formalism of pure spinors in terms of a finite number of holomorphic functions. Alternatively, the solutions can be viewed as vacua of maximally supersymmetric supergravity in six dimensions with a set of scalar fields varying holomorphically over $\\mathbb{C}$. For a class of solutions characterised by up to five holomorphic functions, we outline how the local solutions can be completed to four-dimensional flux vacua of type IIB theory. A detailed study of this global completion for solutions with two holomorphic functions has been carried out in the companion paper [1]. The fluxes of the global solutions ar...

Candelas, Philip; Damian, Cesar; Larfors, Magdalena; Morales, Jose Francisco

2014-01-01

88

Digital Repository Infrastructure Vision for European Research (DRIVER)

We extract the statistical uncertainties for the pion-nucleon ($\\pi N$) low energy constants (LECs) up to fourth order $\\mathcal{O}(Q^4)$ in the chiral expansion of the nuclear effective Lagrangian. The LECs are optimized with respect to experimental scattering data. For comparison, we also present an uncertainty quantification that is based solely on \\pin{} scattering phase shifts. Statistical errors on the LECs are critical in order to estimate the subsequent uncertainties...

Wendt, K. A.; Carlsson, B. D.; Ekstro?m, A.

2014-01-01

89

DEFF Research Database (Denmark)

Degradation of collagen in the arterial wall by matrix metalloproteinases is the hallmark of atherosclerosis. We have developed an ELISA for the quantification of type III collagen degradation mediated by MMP-9 in urine.

Wang, Jianxia; Rasmussen, Lars Melholt

2011-01-01

90

Product-group unification in type IIB string theory

International Nuclear Information System (INIS)

The product-group unification is a model of unified theories, in which the masslessness of the two Higgs doublets and the absence of dimension-5 proton decay are guaranteed by a symmetry. It is based on the SU(5)xU(N)(N=2,3) gauge group. It is known that various features of the model are explained naturally when it is embedded in a brane world. An idea of how to accommodate all the particles of the model in the type-IIB brane world is described. The GUT-breaking sector is realized by a D3-D7 system, and chiral quarks and leptons arise from the intersection off D7-branes. The D-brane configuration can be a geometric realization of the nonparallel family structure of quarks and leptons, an idea proposed to explain the large mixing angles observed in neutrino oscillations. The trilinear interaction of the next-to-minimal supersymmetric standard model is obtained naturally in some cases

91

Type IIA flux compactifications. Vacua, effective theories and cosmological challenges

International Nuclear Information System (INIS)

In this thesis, we studied a number of type IIA SU(3)-structure compactifications with 06-planes on nilmanifolds and cosets, which are tractable enough to allow for an explicit derivation of the low energy effective theory. In particular we calculated the mass spectrum of the light scalar modes, using N = 1 supergravity techniques. For the torus and the Iwasawa solution, we have also performed an explicit Kaluza-Klein reduction, which led to the same result. For the nilmanifold examples we have found that there are always three unstabilized moduli corresponding to axions in the RR sector. On the other hand, in the coset models, except for SU(2) x SU(2), all moduli are stabilized. We discussed the Kaluza-Klein decoupling for the supersymmetric AdS vacua and found that it requires going to the Nearly-Calabi Yau limited. We searched for non-trivial de Sitter minima in the original flux potential away from the AdS vacuum. Finally, in chapter 7, we focused on a family of three coset spaces and constructed non-supersymmetric vacua on them. (orig.)

92

Type IIA flux compactifications. Vacua, effective theories and cosmological challenges

Energy Technology Data Exchange (ETDEWEB)

In this thesis, we studied a number of type IIA SU(3)-structure compactifications with 06-planes on nilmanifolds and cosets, which are tractable enough to allow for an explicit derivation of the low energy effective theory. In particular we calculated the mass spectrum of the light scalar modes, using N = 1 supergravity techniques. For the torus and the Iwasawa solution, we have also performed an explicit Kaluza-Klein reduction, which led to the same result. For the nilmanifold examples we have found that there are always three unstabilized moduli corresponding to axions in the RR sector. On the other hand, in the coset models, except for SU(2) x SU(2), all moduli are stabilized. We discussed the Kaluza-Klein decoupling for the supersymmetric AdS vacua and found that it requires going to the Nearly-Calabi Yau limited. We searched for non-trivial de Sitter minima in the original flux potential away from the AdS vacuum. Finally, in chapter 7, we focused on a family of three coset spaces and constructed non-supersymmetric vacua on them. (orig.)

Koers, Simon

2009-07-30

93

A systematic framework for incubation of damage- state quantification in composites is almost absent in the current practice. Identification and quantification of the material state at its early stage has become significantly important in the field of structural health monitoring. Interaction between the intrinsic material state and ultrasonic wave signals, e.g., nonlinear ultrasonic, higher harmonic generation, etc., in metals are quite well known and well documented in the literature. However, it is extremely challenging to quantify the precursor to damage state in composite materials. Thus, in this paper, a comparatively simple but efficient novel approach is proposed to quantify the "incubation of damage" state using scanning acoustic microscopy. The proposed approach exploits the hybrid microcontinuum field theory to quantify the intrinsic (multi-scale) damage state. Defying the conventional route of bottom-up multi-scale modeling methods, a hybrid top-down approach is presented, which is then correlated to the ultrasonic signature obtained from the materials. A parameter to quantify incubation of damage at meso-scale has been identified in this paper. The intrinsic length-scale-dependent parameter called "damage entropy" closely resembles the material state resulting from fatigue, extreme environments, operational hazards or spatio-temporal variability, etc. The proposed quantification process involves a fusion between micromorphic physics and high-frequency ultrasonics in an unconventional way. The proposed approach is validated through an experimental study conducted on glass-fiber reinforced polymer composites which are mechanically fatigued. Specimens were characterized under a scanning acoustic microscope at 50 and 100 MHz. The imaging data and the sensor signals are characterized to quantify the incubation of damage state by the new parameter damage entropy. PMID:25004477

Banerjee, Sourav; Ahmed, Riaz

2013-06-01

94

Twisted N=8, D=2 super Yang-Mills theory as example of a Hodge-type cohomological theory

It is shown that the dimensional reduction of the N_T=2, D=3 Blau-Thompson model to D=2, i.e., the novel topological twist of N=8, D=2 super Yang-Mills theory, provides an example of a Hodge-type cohomological theory. In that theory the generators of the topological shift, co-shift and gauge symmetry, together with a discrete duality operation, are completely analogous to the de Rham cohomology operators and the Hodge *-operation.

Geyer, B

2001-01-01

95

Experiments dealing with quantification processes in adults were run as part of an attempt to formulate an information processing model of cognitive development. The existence of three quantification operators--subitizing, counting and estimation--was first postulated. Experiments were then designed to refine the parameters which define the…

Klahr, David

96

Krichever-Novikov type algebras theory and applications

Krichever and Novikov introduced certain classes of infinite dimensionalLie algebrasto extend the Virasoro algebra and its related algebras to Riemann surfaces of higher genus. The author of this book generalized and extended them toa more general setting needed by the applications. Examples of applications are Conformal Field Theory, Wess-Zumino-Novikov-Witten models, moduli space problems, integrable systems, Lax operator algebras, and deformation theory of Lie algebra. Furthermore they constitute an important class of infinite dimensional Lie algebras which due to their geometric origin are

Schlichenmaier, Martin

2014-01-01

97

Initial layer theory and model equations of Volterra type

International Nuclear Information System (INIS)

It is demonstrated here that there exist initial layers to singularly perturbed Volterra equations whose thicknesses are not of order of magnitude of 0(?), ? ? 0. It is also shown that the initial layer theory is extremely useful because it allows one to construct the approximate solution to an equation, which is almost identical to the exact solution. (author)

98

This research investigates the effect of nine physical treatment types comprising a serial combination of three drying (air, freeze and oven) and two comminution (milling and sieving) methods on the quantification of PAH in a soil sample from a former gasworks. Results show that treatment type has a significant effect on PAH concentration (p?0.05). Naphthalene, 1-methylnaphthalene and 2-methylnaphthalene concentrations were significantly higher for air drying and freeze drying treatments than for oven drying. It is suggested that naphthalene and similarly volatile PAH losses were greater for oven drying due to the application of fanned warm air which is thought to cause volatilisation. Analytical precision was significantly improved for milled samples compared with sieved samples. The reason milling results in greater precision is assigned to the improved solvent extraction efficiency when natural grain size is altered due to crushing. The analytical data were compared to residential generic assessment criteria (GAC) used for risk-based land management. It was shown that the naphthalene GAC was lower than all freeze drying and air drying concentrations but was within the oven drying concentration range, illustrating that a false negative could be concluded during risk evaluation is oven dried data were used. Overall, it is recommended that air drying or freeze drying is a better choice than oven drying if the quantification of low molecular weight PAH forms an important objective of sample characterisation for risk-based land management, otherwise freeze drying and milling is recommended. PMID:24997944

Beriro, Darren J; Vane, Christopher H; Cave, Mark R; Nathanail, C Paul

2014-09-01

99

Personality and Type (but "Not" a Psychological Theory!)

Word processing is part of every writer's set of competencies today, and as readers, their expectations of type have risen well beyond the old Courier font of typewriters. Yet only recently have writers had access to the thousands of different typefaces available today and had such power in making design choices. Type has been much studied and…

Holst-Larkin, Jane

2006-01-01

100

Bianchi Types V and VI0 Cosmic Strings Coupled with Maxwell Fields in Bimetric Theory

Spatially homogeneous Bianchi types V and VI0 cosmological models are studied with source cosmic cloud strings coupled with electromagnetic field in Rosen's (Gen. Relativ. Gravit. 4:435, 1973) bimetric theory of relativity. It is observed that Bianchi type V space time is feasible whereas Bianchi type VI0 is not feasible. In the feasible case different equations of state for cosmic strings with Maxwell fields do not survive in this theory and the space-time turns out to be flat.

Sahoo, P. K.; Mishra, B.; Ramu, A.

2011-02-01

101

Treatment strategies in acute ischemic stroke are still limited. Considering numerous translation failures, research is tending to a preferred use of human-like animal models, and a more-complex perspective of tissue salvaging involving endothelial, glial and neuronal components according to the neurovascular unit (NVU) concept. During ischemia, blood-brain barrier (BBB) alterations lead to brain edema and hemorrhagic transformation affecting NVU components. The present study aims on a novel quantification method of BBB damage and affected tissue following experimental cerebral ischemia, closely to the human condition. Wistar rats underwent embolic middle cerebral artery occlusion, followed by an intravenous application of fluorescein isothiocyanate (FITC)-tagged albumin (?70kDa) and/or biotinylated rat IgG (?150kDa) as BBB permeability markers. Both fluorescent agents revealed similar leakage and allow quantification of BBB permeability by fluorescence microscopy, and after immunohistochemical conversion into a permanent diaminobenzidine label at light-microscopical level. The following markers were identified for sufficient detection of NVU components: Rat endothelial cell antigen-1 (RECA) and laminin for vessels, Lycopersicon esculentum and Griffonia simplicifolia agglutinin for vessels and microglial subpopulations, ionized calcium binding adaptor molecule 1 (Iba1), CD68 and CD11b for macrophages, activated microglia, monocytes and neutrophils, S100? for astroglia, as well as NeuN and HuC/D for neurons. This is the first report confirming the usefulness of simultaneously applied FITC-albumin and biotinylated rat IgG as BBB permeability markers in experimental stroke, and, specifying antibodies and lectins for multiple fluorescence labeling of NVU components. Newly elaborated protocols might facilitate a more-complex outcome measurement in drug development for cerebral ischemia. PMID:20732314

Michalski, Dominik; Grosche, Jens; Pelz, Johann; Schneider, Dietmar; Weise, Christopher; Bauer, Ute; Kacza, Johannes; Gärtner, Ulrich; Hobohm, Carsten; Härtig, Wolfgang

2010-11-01

102

On M-theory and the symmetries of type II string effective actions

International Nuclear Information System (INIS)

We study the ''ordinary'' Scherk-Schwarz dimensional reduction of the bosonic sector of the low energy effective action of a hypothetical M-theory on S1 x S1?T2. We thus obtain the low energy effective actions of type IIA string theory in both ten and nine space-time dimensions. We point out how to obtain the O(1,1) invariance of the NS-NS sector of the string effective action correctly in nine dimensions. We dimensionally reduce the type IIB string effective action on S1 and show that the resulting nine-dimensional theory can be mapped, purely from the bosonic consideration, exactly to the type IIA theory by an O(1,1) or Buscher's T-duality transformations. We then give a dynamical argument, in analogy with that for the type IIB theory in ten dimensions, to show how an S-duality in the type IIA theory can be understood from the underlying nine-dimensional theory by compactifying M-theory on a T-dual torus T2. (orig.)

103

A real-time PCR assay, based on Primer-Probe Energy Transfer (PriProET), was developed to improve the detection and quantification of porcine circovirus type 2 (PVC2). PCV2 is recognised as the essential infectious agent in post-weaning multisystemic wasting syndrome (PMWS) and has been associated with other disease syndromes such as porcine dermatitis and nephropathy syndrome (PDNS) and porcine respiratory disease complex (PRDC). Since circoviruses commonly occur in the pig populations and there is a correlation between the severity of the disease and the viral load in the organs and blood, it is important not only to detect PCV2 but also to determine the quantitative aspects of viral load. The PriProET real-time PCR assay described in this study was tested on various virus strains and clinical forms of PMWS in order to investigate any correlation between the clinical signs and viral loads in different organs. The data obtained in this study correlate with those described earlier; namely, the viral load in 1 ml plasma and in 500 ng tissue DNA exceeds 10(7) copies in the case of PMWS. The results indicate that the new assay provides a specific, sensitive and robust tool for the improved detection and quantification of PCV2. PMID:19635716

Bálint, Adám; Tenk, Miklós; Deim, Zoltán; Rasmussen, Thomas Bruun; Uttenthal, Ase; Cságola, Attila; Tuboly, Tamás; Farsang, Attila; Fossum, Caroline; Timmusk, Sirje; Berg, Mikael; Belák, Sándor

2009-09-01

104

DEFF Research Database (Denmark)

A real-time PCR assay, based on Primer-Probe Energy Transfer (PriProET), was developed to improve the detection and quantification of porcine circovirus type 2 (PVC2). PCV2 is recognised as the essential infectious agent in post-weaning multisystemic wasting syndrome (PMWS) and has been associated with other disease syndromes such as porcine dermatitis and nephropathy syndrome (PDNS) and porcine respiratory disease complex (PRDC). Since circoviruses commonly occur in the pig populations and there is a correlation between the severity of the disease and the viral load in the organs and blood, it is important not only to detect PCV2 but also to determine the quantitative aspects of viral load. The PriProET real-time PCR assay described in this study was tested on various virus strains and clinical forms of PMWS in order to investigate any correlation between the clinical signs and viral loads in different organs. The data obtained in this study correlate with those described earlier; namely, the viral load in 1ml plasma and in 500 ng tissue DNA exceeds 10(7) copies in the case of PMWS. The results indicate that the new assay provides a specific, sensitive and robust tool for the improved detection and quantification of PCV2.

Rasmussen, Thomas Bruun; Uttenthal, Åse

2009-01-01

105

Applications of differential sensitivity theory for extremum-type responses

International Nuclear Information System (INIS)

A recently developed sensitivity theory for nonlinear systems with responses defined at critical points, e.g. maxima, minima, or saddle points, of a function of the system's state variables and parameters is applied to a protected transient with scram on high power level in the Fast Flux Test Facility. The single-phase segment of the fast reactor safety code MELT-III B is used to model this transient. Two responses of practical importance, viz. The maximum fuel temperature in the hot channel, and the maximum normalized reactor power level, are considered. For the purposes of sensitivity analysis, a complete characterization of such responses requires consideration of both the numerical value of the response at the maximum, and the location in phase-space where the maximum occurs. This is because variations in the system parameters alter not only the value at this maximum but also alter the location of the maximum in phase-space

106

On type IIA string theory on the Pp-wave background

International Nuclear Information System (INIS)

We study type IIA superstring theory on a PP-wave background with 24 supercharges. This model can exactly be solved up to quadratic fermionic action and then quantized. The open string in this PP-wave background is also studied. We observe that the theory has supersymmetric Dp-branes for p=2,4,6,8

107

On the Ricci tensor in the common sector of type II string theory

Let ? be a metric connection with totally skew-symmetric torsion T on a Riemannian manifold. Given a spinor field ? and a dilaton function ?, the basic equations in the common sector of type II string theory are \\fl \

Agricola, I.; Friedrich, T.; Nagy, P.-A.; Puhle, C.

2005-07-01

108

On the theory of type IV solar radio bursts

International Nuclear Information System (INIS)

The excitation of plasma waves in a magnetic trap (arch) with a constantly acting source of energetic electrons is analyzed in a quasi-linear approximation with allowance for the simultaneous excitation of electromagnetic waves: whistlers. The energy density of plasma waves and the density of charged particles in the trap are estimated. The blending of plasma waves yields the flux of radio emission at the second harmonic of the plasma frequency observed in a type IV burst

109

Bianchi Type-II, VIII & IX Perfect Fluid Cosmological Models in Brans Dicke Theory of Gravitation

Directory of Open Access Journals (Sweden)

Full Text Available Field equations in the presence of perfect fluid distribution are obtained in a scalar tensor theory of gravitation proposed by Brans and Dicke[1] with the aid of Bianchi type-II, VIII & IX metrics. Exact prefect fluid Bianchi type- IX cosmological model is presented since other models doesn’t exist in Brans-Dicke scalar tensor theory of gravitation. Some physical properties of the model are also discussed.

Velagapudi Uma Maheswara Rao

2011-10-01

110

Denotation of syntax and metaprogramming in contextual modal type theory (CMTT)

The modal logic S4 can be used via a Curry-Howard style correspondence to obtain a lambda-calculus. Modal (boxed) types are intuitively interpreted as `closed syntax of the calculus'. This lambda-calculus is called modal type theory --- this is the basic case of a more general contextual modal type theory, or CMTT. CMTT has never been given a denotational semantics in which modal types are given denotation as closed syntax. We show how this can indeed be done, with a twist. We also use the denotation to prove some properties of the system.

Gabbay, Murdoch

2012-01-01

111

Theory of Zonal Flow Generation by Flute Type Turbulence

Energy Technology Data Exchange (ETDEWEB)

The theory of zonal flows generation by Reynolds stress is extended by flute (interchange), mode turbulence. The specific role of density fluctuations and finite Larmor radius effects is clarified. To describe the dynamics of a large-scale plasma flow that varies on a longer time scale compared to the small-scale fluctuations, a multiple scale expansion is employed, assuming that there is a sufficient spectral gap separating large-scale and small-scale motions. The evolution equations for mean flow generation with sources consisting of the standard and diamagnetic (due to the density fluctuations) Reynolds stresses are obtained by averaging the model equations over fast small scales. Analysis of these equations shows that diamagnetic effects may significantly enhance the total Reynolds force. The possibility of mean flow generation by the ensemble-averaged external J x B force is shown to yield results which agree with the calculation of the flow generation by Reynolds stresses. The physics of the acceleration mechanism is elucidated.

Andrushchenko, Zh.N. [National Academy of Sciences of Ukraine, Kiev (Ukraine). Inst. for Nuclear Research; Pavlenko, V.P. [Uppsala Univ. (Sweden). Dept. of Astronomy and Space Physics; Schoepf, K. [Univ. of Innsbruck (Austria). Inst. for Theoretical Physics

2002-10-01

112

Theory of Zonal Flow Generation by Flute Type Turbulence

International Nuclear Information System (INIS)

The theory of zonal flows generation by Reynolds stress is extended by flute (interchange), mode turbulence. The specific role of density fluctuations and finite Larmor radius effects is clarified. To describe the dynamics of a large-scale plasma flow that varies on a longer time scale compared to the small-scale fluctuations, a multiple scale expansion is employed, assuming that there is a sufficient spectral gap separating large-scale and small-scale motions. The evolution equations for mean flow generation with sources consisting of the standard and diamagnetic (due to the density fluctuations) Reynolds stresses are obtained by averaging the model equations over fast small scales. Analysis of these equations shows that diamagnetic effects may significantly enhance the total Reynolds force. The possibility of mean flow generation by the ensemble-averaged external J x B force is shown to yield results which agree with the calculation of the flow generation by Reynolds stresses. The physics of the acceleration mechanism is elucidated

113

Coleman-Weinberg Mechanism and Interaction of D3-Branes in Type 0 String Theory

The low-energy theory on the world volume of parallel static D3-branes of type 0 strings is the Yang-Mills theory with six scalar fields in the adjoint representation. One-loop corrections in this theory induce Coleman-Weinberg effective potential, which can be interpreted as an interaction energy of D3-branes. The potential is repulsive at short distances and attractive at large ones. In the equilibrium, a large number of D3-branes forms a spherical shell with the radius proportional to the characteristic energy scale of the world-volume theory.

Zarembo, K

1999-01-01

114

Generalized N?=?1 and N?=?2 structures in M-theory and type II orientifolds

Digital Repository Infrastructure Vision for European Research (DRIVER)

We consider M-theory and type IIA reductions to four dimensions with N?=?2 and N?=?1 supersymmetry and discuss their interconnection. Our work is based on the framework of Exceptional Generalized Geometry (EGG), which extends the tangent bundle to include all symmetries in M-theory and type II string theory, covariantizing the local U-duality group E 7(7). We describe general N?=?1 and N?=?2 reductions in terms of SU(7) and SU(6) structures on this bundle and thereby derive th...

Gran?a, Mariana; Triendl, Hagen

2013-01-01

115

Vortex-type half-BPS solitons in Aharony-Bergman-Jafferis-Maldacena theory

International Nuclear Information System (INIS)

We study the Aharony-Bergman-Jafferis-Maldacena (ABJM) theory without and with mass deformation. It is shown that maximally supersymmetry preserving, D-term, and F-term mass deformations of single mass parameter are equivalent. We obtain vortex-type half-BPS equations and the corresponding energy bound. For the undeformed ABJM theory, the resulting half-BPS equation is the same as that in supersymmetric Yang-Mills theory and no finite energy regular BPS solution is found. For the mass-deformed ABJM theory, the half-BPS equations for U(2)xU(2) case reduce to the vortex equation in Maxwell-Higgs theory, which supports static regular multivortex solutions. In U(N)xU(N) case with N>2 the non-Abelian vortex equation of Yang-Mills-Higgs theory is obtained.

116

On Type IIA Penrose Limit and N=6 Chern-Simons Theories

Recently, Aharony, Bergman, Jafferis and Maldacena proposed that the N=6 Chern-Simons gauge theories are holographically dual to the M-theory backgrounds with multiple M2-branes on orbifolds C^4/Z_k. When k is large, they have the type IIA string description. In this paper we analyze the Penrose limit of this IIA background and express the string spectrum as the conformal dimensions of operators in the gauge theories. For BPS operators, we can confirm the agreements between the IIA string on plane waves and the gauge theories. We point out that there exist BMN-like operators in the gauge theories, though their holographic interpretation does not seem to be simple. Also we analyze the weak coupling limit of this theory and show that the Hagedorn/deconfinement transition occurs as expected.

Nishioka, Tatsuma

2008-01-01

117

On Lorentz violation in Horava-Lifshitz type theories

We show that coupling the Standard Model to a Lorentz symmetry violating sector may co-exist with viable phenomenology, provided that the interaction between the two is mediated by higher-dimensional operators. In particular, if the new sector acquires anisotropic scaling behavior above a "Horava-Lifshitz" energy scale $\\Lambda_L$ and couples to the Standard Model through interactions suppressed by the Planck mass M_p, the transmission of the Lorentz violation into the Standard Model is protected by the ratio $\\LambdaHL^2/M_p^2$. A wide scale separation, $\\Lambda_L<

Pospelov, Maxim

2010-01-01

118

Digital Repository Infrastructure Vision for European Research (DRIVER)

The roles of microarchitecture and types of trabeculae in determining elastic modulus of trabecular bone have been studied in ?CT images of 29 trabecular bone samples by comparing their Young’s moduli calculated by finite element analysis (FEA) with different trabecular type-specific reconstructions. The results suggest that trabecular plates play an essential role in determining elastic properties of trabecular bone.

Liu, Xiaowei S.; Sajda, Paul; Saha, Punam K.; Wehrli, Felix W.; Guo, X. Edward

2006-01-01

119

Abelian gauge symmetries and fluxed instantons in compactifications of type IIB and F-theory

Energy Technology Data Exchange (ETDEWEB)

We discuss the role of Abelian gauge symmetries in type IIB orientifold compactifications and their F-theory uplift. Particular emphasis is placed on U(1)s which become massive through the geometric Stueckelberg mechanism in type IIB. We present a proposal on how to take such geometrically massive U(1)s and the associated fluxes into account in the Kaluza-Klein reduction of F-theory with the help of non-harmonic forms. Evidence for this proposal is obtained by working out the F-theory effective action including such non-harmonic forms and matching the results with the known type IIB expressions. We furthermore discuss how world-volume fluxes on D3-brane instantons affect the instanton charge with respect to U(1) gauge symmetries and the chiral zero mode spectrum. The classical partition function of M5-instantons in F-theory is discussed and compared with the type IIB results for D3-brane instantons. The type IIB match allows us to determine the correct M5 partition function. Selection rules for the absence of chiral charged zero modes on M5-instantons in backgrounds with G{sub 4} flux are discussed and compared with the type IIB results. The dimensional reduction of the democratic formulation of M-theory is presented in the appendix.

Buenaventura Kerstan, Max Bromo

2013-11-13

120

Abelian gauge symmetries and fluxed instantons in compactifications of type IIB and F-theory

International Nuclear Information System (INIS)

We discuss the role of Abelian gauge symmetries in type IIB orientifold compactifications and their F-theory uplift. Particular emphasis is placed on U(1)s which become massive through the geometric Stueckelberg mechanism in type IIB. We present a proposal on how to take such geometrically massive U(1)s and the associated fluxes into account in the Kaluza-Klein reduction of F-theory with the help of non-harmonic forms. Evidence for this proposal is obtained by working out the F-theory effective action including such non-harmonic forms and matching the results with the known type IIB expressions. We furthermore discuss how world-volume fluxes on D3-brane instantons affect the instanton charge with respect to U(1) gauge symmetries and the chiral zero mode spectrum. The classical partition function of M5-instantons in F-theory is discussed and compared with the type IIB results for D3-brane instantons. The type IIB match allows us to determine the correct M5 partition function. Selection rules for the absence of chiral charged zero modes on M5-instantons in backgrounds with G4 flux are discussed and compared with the type IIB results. The dimensional reduction of the democratic formulation of M-theory is presented in the appendix.

121

The local universes model: an overlooked coherence construction for dependent type theories

Digital Repository Infrastructure Vision for European Research (DRIVER)

We present a new coherence theorem for comprehension categories, providing strict models of dependent type theory with all standard constructors, including dependent products, dependent sums, identity types and, indeed, all inductive types. We assume throughout that the base category is close to being locally Cartesian closed: specifically, that products and certain exponentials exist. Beyond this, we require only that the logical structure should be *weakly stable* ---...

Lumsdaine, Peter Lefanu; Warren, Michael A.

2014-01-01

122

Cartan's equations define a topological field theory of the BF type

International Nuclear Information System (INIS)

Cartan's first and second structure equations together with first and second Bianchi identities can be interpreted as equations of motion for the tetrad, the connection and a set of two-form fields TI and RJI. From this viewpoint, these equations define by themselves a field theory. Restricting the analysis to four-dimensional spacetimes (keeping gravity in mind), it is possible to give an action principle of the BF type from which these equations of motion are obtained. The action turns out to be equivalent to a linear combination of the Nieh-Yan, Pontrjagin, and Euler classes, and so the field theory defined by the action is topological. Once Einstein's equations are added, the resulting theory is general relativity. Therefore, the current results show that the relationship between general relativity and topological field theories of the BF type is also present in the first-order formalism for general relativity

123

Hamiltonian BRST deformation of a class of n-dimensional BF-type theories

International Nuclear Information System (INIS)

Consistent hamiltonian interactions that can be added to an abelian free BF-type class of theories in any n?4 spacetime dimensions are constructed in the framework of the hamiltonian BRST deformation based on cohomological techniques. The resulting model is an interacting field theory in higher dimensions with an open algebra of on-shell reducible first-class constraints. We argue that the hamiltonian couplings are related to a natural structure of Poisson manifold on the target space. (author)

124

Nonperturbative type IIB model building in the F-theory framework

Energy Technology Data Exchange (ETDEWEB)

This dissertation is concerned with the topic of non-perturbative string theory, which is generally considered to be the most promising approach to a consistent description of quantum gravity. The five known 10-dimensional perturbative string theories are all interconnected by numerous dualities, such that an underlying non-perturbative 11-dimensional theory, called M-theory, is postulated. Due to several technical obstacles, little is known about the fundamental objects in this theory. There exists an alternative non-perturbative description to type IIB string theory, namely F-theory. Here the SL(2;Z) self-duality of IIB theory is geometrized in the form of an elliptic fibration over the space-time. Moreover, higher-dimensional objects like 7-branes are included via singularities into the geometric picture. This formally elegant description, however, requires significant technical effort for the construction of suitable compactification geometries, as many different aspects necessarily have to be dealt with at the same time. On the other hand, the generation of essential GUT building blocks like certain Yukawa couplings or spinor representations is easier compared to perturbative string theory. The goal of this study is therefore to formulate a unified theory within the framework of F-theory, that satisfies basic phenomenological constraints. Within this thesis, at first E3-brane instantons in type IIB string theory - 4-dimensional objects that are entirely wrapped around the invisible dimensions of space-time - are matched with M5-branes in F-theory. Such objects are of great importance in the generation of critical Yukawa couplings or the stabilization of the free parameters of a theory. Certain properties of M5-branes then allow to derive a new criterion for E3-branes to contribute to the superpotential. In the aftermath of this analysis, several compactification geometries are constructed and checked for basic properties that are relevant for semi-realistic unified model building. An important aspect is the proper handling of the gauge flux on the 7-branes. Via the spectral cover description - which at first requires further refinements - chiral matter can be generated and the unified gauge group can be broken to the Standard Model. Ultimately, in this thesis an explicit unified model based on the gauge group SU(5) is constructed within the F-theory framework, such that an acceptable phenomenology and the observed three chiral matter generations are obtained. (orig.)

Jurke, Benjamin Helmut Friedrich

2011-02-28

125

Digital Repository Infrastructure Vision for European Research (DRIVER)

Information about current land cover type is essential at a certain level to ensure the optimum use of the land resources. Several approaches can be used to estimate land cover area, where remote sensing and Geographic Information System (GIS) is among the method. Therefore, this study was undertaken to evaluate how reliable these technologies in preparing information about land cover in Carey Island, Selangor of Peninsular Malaysia. Erdas Imagine 9.1 was used in digital image processing. A p...

J Hj. Kamaruzaman,; I Mohd Hasmadi,

2009-01-01

126

DEFF Research Database (Denmark)

Coalescence of polymer particles in polymer matrix tablets influences drug release. The literature has emphasized that coalescence occurs above the glass transition temperature (Tg) of the polymer and that water may plasticize (lower Tg) the polymer. However, we have shown previously that nonplasticizing water also influences coalescence of Eudragit RLPO; so there is a need to quantify the different types of water in Eudragit RLPO. The purpose of this study was to distinguish the types of water present in Eudragit RLPO polymer and to investigate the water loss kinetics for these different types of water. Eudragit RLPO was stored in tightly closed chambers at various relative humidities (0, 33, 56, 75, and 94%) until equilibrium was reached. Fourier transform infrared spectroscopy (FTIR)-DRIFTS was used to investigate molecular interactions between water and polymer, and water loss over time. Using a curve fitting procedure, the water region (3100-3,700 cm(-1)) of the spectra was analyzed, and used to identifywater present in differing environments in the polymer and to determine the water loss kinetics upon purging the sample with dry compressed air. It was found that four environments can be differentiated (dipole interaction of water with quaternary ammonium groups, water cluster, and water indirectly and directly binding to the carbonyl groups of the polymer) but it was not possible to distinguish whether the different types of water were lost at different rates. It is suggested that water is trapped in the polymer in different forms and this should be considered when investigating coalescence of polymer matrices.

Pirayavaraporn, Chompak; Rades, Thomas

2013-01-01

127

Coalescence of polymer particles in polymer matrix tablets influences drug release. The literature has emphasized that coalescence occurs above the glass transition temperature (Tg) of the polymer and that water may plasticize (lower Tg) the polymer. However, we have shown previously that nonplasticizing water also influences coalescence of Eudragit RLPO; so there is a need to quantify the different types of water in Eudragit RLPO. The purpose of this study was to distinguish the types of water present in Eudragit RLPO polymer and to investigate the water loss kinetics for these different types of water. Eudragit RLPO was stored in tightly closed chambers at various relative humidities (0, 33, 56, 75, and 94%) until equilibrium was reached. Fourier transform infrared spectroscopy (FTIR)-DRIFTS was used to investigate molecular interactions between water and polymer, and water loss over time. Using a curve fitting procedure, the water region (3100-3,700 cm(-1)) of the spectra was analyzed, and used to identify water present in differing environments in the polymer and to determine the water loss kinetics upon purging the sample with dry compressed air. It was found that four environments can be differentiated (dipole interaction of water with quaternary ammonium groups, water cluster, and water indirectly and directly binding to the carbonyl groups of the polymer) but it was not possible to distinguish whether the different types of water were lost at different rates. It is suggested that water is trapped in the polymer in different forms and this should be considered when investigating coalescence of polymer matrices. PMID:24144952

Pirayavaraporn, Chompak; Rades, Thomas; Gordon, Keith C; Tucker, Ian G

2013-12-15

128

Methanol has recently attracted renewed interest because of its potential importance as a solar fuel. Methanol is also an important bulk chemical that is most efficiently formed over the industrial Cu/ZnO/Al2O3 catalyst. The identity of the active site and, in particular, the role of ZnO as a promoter for this type of catalyst is still under intense debate. Structural changes that are strongly dependent on the pretreatment method have now been observed for an industrial-type methanol synthesis catalyst. A combination of chemisorption, reaction, and spectroscopic techniques provides a consistent picture of surface alloying between copper and zinc. This analysis enables a reinterpretation of the methods that have been used for the determination of the Cu surface area and provides an opportunity to independently quantify the specific Cu and Zn areas. This method may also be applied to other systems where metal-support interactions are important, and this work generally addresses the role of the carrier and the nature of the interactions between carrier and metal in heterogeneous catalysts. PMID:24764288

Kuld, Sebastian; Conradsen, Christian; Moses, Poul Georg; Chorkendorff, Ib; Sehested, Jens

2014-06-01

129

DEFF Research Database (Denmark)

Two alpha-amylase-producing strains of Aspergillus oryzae, a wild-type strain and a recombinant containing additional copies of the alpha-amylase gene, were characterized,vith respect to enzyme activities, localization of enzymes to the mitochondria or cytosol, macromolecular composition, and metabolic fluxes through the central metabolism during glucose-limited chemostat cultivations. Citrate synthase and isocitrate dehydrogenase (NAD) activities were found only in the mitochondria, glucose-6-phosphate dehydrogenase and glutamate dehydrogenase (NADP) activities were found only in the cytosol, and isocitrate dehydrogenase (NADP), glutamate oxaloacetate transaminase, malate dehydrogenase, and glutamate dehydrogenase (NAD) activities were found in both the mitochondria and the cytosol, The measured biomass components and ash could account for 95% (wt/wt) of the biomass. The protein and RNA contents increased linearly with increasing specific growth rate, but the carbohydrate and chitin contents decreased. A metabolic model consisting of 69 fluxes and 59 intracellular metabolites was used to calculate the metabolic fluxes through the central metabolism at several specific growth rates, with ammonia or nitrate as the nitrogen source. The flux through the pentose phosphate pathway increased with increasing specific growth rate. The fluxes through the pentose phosphate pathway were 15 to 26% higher for the recombinant strain than for the wild-type strain.

Pedersen, Henrik; Carlsen, Morten

1999-01-01

130

Two types of meta-crystals for IV group elements: Density functional theory calculations

International Nuclear Information System (INIS)

Using density function theory (DFT) implemented in VASP package, we find two new type of meta-crystals constructed by IV group elements: Si-568 and Ge-568. The calculational results show that Si-568 has a band gap of 0.09 eV estimated by DFT, while Ge-568 behaves metallic. These two new types of nano-structures both can be created via experimentally observed di-vacancies (DVs) and Stone-Thrower-Wales (STW) defect.

131

Construction of SL(2,Z) invariant amplitudes in type IIB superstring theory

The construction of SL(2,Z) invariant amplitudes that generalize the Virasoro amplitude is investigated in detail. We describe a number of mathematical properties that characterize the simplest example, and present pieces of evidence that it represents the tree-level four-graviton scattering amplitude in membrane theory on $R^9 \\times T^2$ in the limit that the torus area goes to zero. In particular, we show that the poles of the S-dual amplitude are in one-to-one correspondence with the states of membrane theory that survive in the type IIB limit. These are shown to be the states that span the Cartan subspaces of area preserving diffeomorphisms of the 2-torus; all other states become infinitely massive, and membrane world-volume theory acquires the structure of a free theory.

Russo, Jorge G

1998-01-01

132

de Sitter vacua in type IIB string theory: classical solutions and quantum corrections

We revisit the classical theory of ten-dimensional two-derivative gravity coupled to fluxes, scalar fields, D-branes, anti D-branes and Orientifold-planes. We show that such set-ups do not give rise to a four-dimensional positive curvature spacetime with the isometries of de Sitter spacetime. We further argue that a de Sitter solution in type IIB theory may still be achieved if the higher-order curvature corrections are carefully controlled. Our analysis relies on the derivation of the de Sitter condition from an explicit background solution by going beyond the supergravity limit of type IIB theory. As such this also tells us how the background supersymmetry should be broken and under what conditions D-term uplifting can be realized with non self-dual fluxes.

Dasgupta, Keshav; Gwyn, Rhiannon; McDonough, Evan; Mia, Mohammed; Tatar, Radu

2014-07-01

133

International Nuclear Information System (INIS)

We develop a theory of electromagnetically induced transparency in a three-level, ladder-type Doppler-broadened medium, paying special attention to the case where the coupling and probe beams are counterpropagating and have similar frequencies, so as to reduce the total Doppler width of the two-photon process. The theory is easily generalized to deal with the ? configuration, where the ideal arrangement involves two copropagating beams. We discuss different possible regimes, depending on the relative importance of the various broadening mechanisms, and identify ways to optimize the absorption-reduction effect. The theory is compared to the results of a recent experiment (on a ladder-type system), using the Rb D2 line, with generally very good agreement. The maximum absorption reduction observed (64.4%) appears to be mostly limited by the relatively large (?5 MHz) linewidth of the diode lasers used in our experiment

134

de Sitter Vacua in Type IIB String Theory: Classical Solutions and Quantum Corrections

We revisit the classical theory of ten-dimensional two-derivative gravity coupled to fluxes, scalar fields, D-branes, anti D-branes and Orientifold-planes. We show that such set-ups do not give rise to a four-dimensional positive curvature spacetime with the isometries of de Sitter spacetime. We further argue that a de Sitter solution in type IIB theory may still be achieved if the higher-order curvature corrections are carefully controlled. Our analysis relies on the derivation of the de Sitter condition from an explicit background solution by going beyond the supergravity limit of type IIB theory. As such this also tells us how the background supersymmetry should be broken and under what conditions D-term uplifting can be realized with non self-dual fluxes.

Dasgupta, Keshav; McDonough, Evan; Mia, Mohammed; Tatar, Radu

2014-01-01

135

An Abstract Decision Procedure for a Theory of Inductive Data Types

Directory of Open Access Journals (Sweden)

Full Text Available Inductive data types are a valuable modeling tool for software verification. In the past, decision procedures have been proposed for various theories of inductive data types, some focused on the universal fragment, and some focused on handling arbitrary quantifiers. Because of the complexity of the full theory, previous work on the full theory has not focused on strategies for practical implementation. However, even for the universal fragment, previous work has been limited in several significant ways. In this paper, we present a general and practical algorithm for the universal fragment. The algorithm is presented declaratively as a set of abstract rules which we show to be terminating, sound, and complete. We show how other algorithms can be realized as strategies within our general framework, and we propose a new strategy and give experimental results indicating that it performs well in practice. We conclude with a discussion of several useful ways the algorithm can be extended.

Clark Barrett

2007-07-01

136

Spectrum of Maxwell-Chern-Simons theory realized on type IIB brane configurations

Energy Technology Data Exchange (ETDEWEB)

We study the 3D field theory on one D3-brane stretched between (r,s) and (p,q) 5-branes. The boundary conditions are determined from the analysis of NS5 and D5 charges of the two 5-branes. We carry out the mode expansions for all the fields and identify the field theory as Maxwell-Chern-Simons theory. We examine the mass spectrum to determine the conditions for unbroken supersymmetry (SUSY) in this field theory and compare the results with those from the brane configurations. The spectrum is found to be invariant under the Type IIB SL(2,Z) transformation. We also discuss the theory with matter and its S-dual configuration. The result suggests that the equivalence under S-duality may be valid if we include all the heavy modes in the theories with matter. We also find an interesting phenomenon that SUSY enhancement happens in the field theory after dimensional reduction from 3D to 2D.

Kitao, Takuhiro E-mail: kitao@hep1.c.u-tokyo.ac.jp; Ohta, Nobuyoshi E-mail: ohta@phys.sci.osaka-u.ac.jp

2000-07-03

137

Optimal Uncertainty Quantification

We propose a rigorous framework for Uncertainty Quantification (UQ) in which the UQ objectives and the assumptions/information set are brought to the forefront. This framework, which we call \\emph{Optimal Uncertainty Quantification} (OUQ), is based on the observation that, given a set of assumptions and information about the problem, there exist optimal bounds on uncertainties: these are obtained as extreme values of well-defined optimization problems corresponding to extremizing probabilities of failure, or of deviations, subject to the constraints imposed by the scenarios compatible with the assumptions and information. In particular, this framework does not implicitly impose inappropriate assumptions, nor does it repudiate relevant information. Although OUQ optimization problems are extremely large, we show that under general conditions, they have finite-dimensional reductions. As an application, we develop \\emph{Optimal Concentration Inequalities} (OCI) of Hoeffding and McDiarmid type. Surprisingly, contr...

Owhadi, Houman; Sullivan, Timothy John; McKerns, Mike; Ortiz, Michael

2010-01-01

138

Diffusion, Uptake and Release of Hydrogen in p-type Gallium Nitride: Theory and Experiment

Energy Technology Data Exchange (ETDEWEB)

The diffusion, uptake, and release of H in p-type GaN are modeled employing state energies from density-function theory and compared with measurements of deuterium uptake and release using nuclear-reaction analysis. Good semiquantitative agreement is found when account is taken of a surface permeation barrier.

MYERS JR.,SAMUEL M.; WRIGHT,ALAN F.; PETERSEN,GARY A.; WAMPLER,WILLIAM R.; SEAGER,CARLETON H.; CRAWFORD,MARY H.; HAN,JUNG

2000-06-27

139

A phenomenological theory of nonlinear saturation of drift wave type instability

International Nuclear Information System (INIS)

A phenomenologically motivated theory of nonlinear saturation of drift wave type instabilities is presented. While density gradient flattening is the physical saturation mechanism for collisional drift wave, that for trapped electron mode is found to be both density and electron temperature gradient flattening. The importance of inclusion of radially nonlocal structure in the nonlinear analysis is demonstrated. (author)

140

LRS Bianchi type II disordered radiation model with a varying ? term in self creation theory

In this paper, we study LRS Bianchi type II cosmological model with a nonzero time-dependent cosmological constant ? for disordered radiation in the framework of Barber's second self creation theory of gravitation. The physical and geometrical aspects of the model with singularities are also discussed.

Yadav, Mahesh Kumar; Jain, Vimal Chand

2011-01-01

141

K'-Theory of a Local Ring of Finite Cohen-Macaulay Type

We study the $K'$-theory of a CM Henselian local ring $R$ of finite Cohen-Macaulay type. In our main theorem we produce a long exact sequence involving the groups $K_i'(R)$ and the $K$-groups of the endomorphism rings of the indecomposable maximal Cohen-Macaulay $R$-modules, along with their residue rings.

Navkal, Viraj

2011-01-01

142

Comment on ''Proof of one-loop finiteness of type-I SO(32) superstring theory''

International Nuclear Information System (INIS)

Reviewing a proof by Clavelli, we find that the parity-conserving one-loop divergences of type-I SO(N) superstring theory with an arbitrary number of external gauge bosons cancel for N = 8 rather than for N = 32

143

T-duality in type II string theory via noncommutative geometry and beyond

International Nuclear Information System (INIS)

This brief survey on how noncommutative and nonassociative geometry appears naturally in the study of T-duality in type II string theory, is essentially a transcript of my talks given at the 21st Nishinomiya-Yukawa Memorial Symposium on Theoretical Physics: Noncommutative Geometry and Quantum Spacetime in Physics, Japan, 11-15 November 2006. (author)

144

Higgs instability in lower-dimensional type-I string theory

International Nuclear Information System (INIS)

In the one-loop-finite six-dimensional type-I theory, a massless multiplet of scalar mesons appears at the tree level which leads at the one-loop level to a Higgs instability. The appearance of small dimensionless numbers is illustrated

145

International Nuclear Information System (INIS)

AISI type 316L stainless steel (SS) was aged at 973 K for time periods up to 200 hours and then assessed for its susceptibility to sensitisation and intergranular corrosion (IGC) by using various tests specified by ASTM A262 Practices A and E, G108 (electrochemical potentiokinetic reactivation (EPR) test). The possibility of using eddy current testing (ECT) to detect sensitisation and IGC was also assessed. The use of ASTM A262 Practice A and E tests indicated sensitisation in the base metal on and after 20 hours of aging. Tensile tests before and after exposure of aged base metals to Cu-CuSO4-H2SO4 solution showed no variation in ultimate tensile strength (UTS) and ductility. Double loop EPR tests indicated an increase in the ratios of charge and peak current densities on reactivation to activation after aging the base metal for 20 hours and above. In the ECT tests, increase in the ratio of EC amplitudes before and after exposure to Cu-CuSO4-H2SO4 solution was observed on aging the base metal beyond 20 hours. These results of ECT correlated very well with the findings of the EPR and practice E tests, indicating that ECT holds promise for on-line monitoring for IGC. (author)

146

In this study, a quantitative real-time PCR was developed to detect and quantify Acanthamoeba spp. in various environmental water samples. The water samples were taken from watershed, water treatment plant, and three thermal spring recreation areas. The overall detection rate was 14.2 % (25/176) for Acanthamoeba spp. The percentages of samples containing Acanthamoeba spp. from river water, raw drinking water, and thermal spring water were 13 % (13/100), 25 % (7/28), and 10.4 % (5/48), respectively. Acanthamoeba spp. concentrations were determined according to SYBR Green quantitative real-time PCR. A plasmid-based standard curve was constructed to determine the Acanthamoeba concentration using dilution factors for achieving 1.36?×?10(9) gene copies per PCR for 18S rRNA gene in Acanthamoeba spp. The resulting concentrations varied by the type of water, in the range of 46-2.6?×?10(2) cells/l in positive raw drinking water, 2.7?×?10(2)-1.5?×?10(4) cells/l in river water, and 54-1.7?×?10(3) cells/l in thermal spring water. The presence of Acanthamoeba spp. in the raw drinking water samples was also found to have a significant difference with heterotrophic plate count. The presence of Acanthamoeba spp. in various aquatic environments may be a potential health hazard and must be further evaluated. PMID:23306384

Kao, Po-Min; Tung, Min-Che; Hsu, Bing-Mu; Tsai, Hsien-Lung; She, Cheng-Yu; Shen, Shu-Min; Huang, Wen-Chien

2013-03-01

147

Exceptional field theory. I. E6(6)-covariant form of M-theory and type IIB

We present the details of the recently constructed E6(6)-covariant extension of 11-dimensional supergravity. This theory requires a 5+27-dimensional spacetime in which the "internal" coordinates transform in the 27 ¯ of E6(6). All fields are E6(6) tensors and transform under (gauged) internal generalized diffeomorphisms. The "Kaluza-Klein" vector field acts as a gauge field for the E6(6)-covariant "E-bracket" rather than a Lie bracket, requiring the presence of 2-forms akin to the tensor hierarchy of gauged supergravity. We construct the complete and unique action that is gauge invariant under generalized diffeomorphisms in the internal and external coordinates. The theory is subject to covariant section constraints on the derivatives, implying that only a subset of the extra 27 coordinates is physical. We give two solutions of the section constraints: the first preserves GL(6) and embeds the action of the complete (i.e. untruncated) 11-dimensional supergravity; the second preserves GL(5)×SL(2) and embeds complete type IIB supergravity. As a byproduct, we thus obtain an off-shell action for type IIB supergravity.

Hohm, Olaf; Samtleben, Henning

2014-03-01

148

Data are accumulating to show that the natural history of human immunodeficiency virus type 1 (HIV-1) in chimpanzees closely reproduces that in humans and is influenced by biologic properties of the infecting HIV-1 strain. To determine the distribution and relative amounts of HIV-1, proviral DNA in multiple tissues from a chimpanzee euthanized because of an abdominal tumor and kidney failure was quantified by nested PCR limiting-dilution assays. At death, 21 months after infection with HIV-1(JC499), this animal had a CD4(+) T-cell count of 268 and 1.7 x 10(5) copies of virion RNA/ml of plasma. The highest proviral burdens were in peripheral lymph nodes and blood, followed by lung, colon, and spleen; values ranged from 130 to 3350 proviral copies/microg DNA (equivalent to DNA in 150,000 cells). The lowest levels of virus were in the spinal cord, brain, and cecum (0.3 to 2.5 copies/microg DNA), with all other tissues harboring intermediate levels (6.8 to 114 copies/microg DNA). Viral burdens in all tissues were comparable to or greater than those reported for HIV-1-infected humans in all stages of disease. Immunohistochemistry for HIV-1 p24 Gag antigen revealed (i) trapping of HIV-1 on follicular dendritic cells in lymph node germinal centers and (ii) virus in the brain, where it was localized primarily to capillary endothelial cells in the cerebral cortex. Analysis of the genetic diversity of the Env V3 loop in tissues indicated that there was no apparent compartmentalization of HIV-1 variants. Of interest, in 83 of 94 (88.3%) clones sequenced, the unique GYGR motif at the tip of the V3 loop of HIV-1(JC499) had reverted to the more common GPGR. The results support the conclusion that HIV-1 has the potential to maintain high viral burdens in chimpanzees and to disseminate to most organs, including the central nervous system. The use of the chimpanzee model with HIV-1(JC499) (or related strains) in vaccine efficacy studies should prove valuable, especially when assessing protection against disease. Furthermore, comparison of both replicative properties of HIV-1(JC499) with SIVcpz strains and immune responses of chimpanzees infected with these viruses might provide new information about HIV pathogenesis. PMID:11021995

Wei, Q; Javadian, A; Lausen, N; Fultz, P N

2000-10-10

149

Classification of Gauge Orbit Types for SU(n)-Gauge Theories

A method for determining the orbit types of the action of the group of gauge transformations on the space of connections for gauge theories with gauge group SU(n) in space-time dimension d<=4 is presented. The method is based on the 1:1-correspondence between orbit types and holonomy-induced Howe subbundles of the underlying principal SU(n)-bundle. It is shown that the orbit types are labelled by certain cohomology elements of space-time satisfying two relations. Thus, for every principal SU(n)-bundle the corresponding stratification of the gauge orbit space can be determined explicitly. As an application, a criterion characterizing kinematical nodes for physical states in 2+1-dimensional Chern-Simons theory proposed by Asorey et al. is discussed.

Rudolph, G; Volobuev, I P; Rudolph, Gerd; Schmidt, Matthias; Volobuev, Igor P.

2002-01-01

150

Generalized N=1 and N=2 structures in M-theory and type II orientifolds

We consider M-theory and type IIA reductions to four dimensions with N=2 and N=1 supersymmetry and discuss their interconnection. Our work is based on the framework of Exceptional Generalized Geometry (EGG), which extends the tangent bundle to include all symmetries in M-theory and type II string theory, covariantizing the local U-duality group E7. We describe general N=1 and N=2 reductions in terms of SU(7) and SU(6) structures on this bundle and thereby derive the effective four-dimensional N=1 and N=2 couplings, in particular we compute the Kahler and hyper-Kahler potentials as well as the triplet of Killing prepotentials (or the superpotential in the N=1 case). These structures and couplings can be described in terms of forms on an eight-dimensional tangent space where SL(8) contained in E7 acts, which might indicate a description in terms of an eight-dimensional internal space, similar to F-theory. We finally discuss an orbifold action in M-theory and its reduction to O6 orientifolds, and show how the pr...

Graña, Mariana

2012-01-01

151

Generalized N = 1 and N = 2 structures in M-theory and type II orientifolds

We consider M-theory and type IIA reductions to four dimensions with N = 2 and N = 1 supersymmetry and discuss their interconnection. Our work is based on the framework of Exceptional Generalized Geometry (EGG), which extends the tangent bundle to include all symmetries in M-theory and type II string theory, covariantizing the local U-duality group E 7(7). We describe general N = 1 and N = 2 reductions in terms of SU(7) and SU(6) structures on this bundle and thereby derive the effective four-dimensional N = 1 and N = 2 couplings, in particular we compute the Kähler and hyper-Kähler potentials as well as the triplet of Killing prepotentials (or the superpotential in the N = 1 case). These structures and couplings can be described in terms of forms on an eight-dimensional tangent space where SL(8) ? E 7 acts, which might indicate a description in terms of an eight-dimensional internal space, similar to F-theory. We finally discuss an orbifold action in M-theory and its reduction to O6 orientifolds, and show how the projection on the N = 2 structures selects the N = 1 ones. We briefly comment on new orientifold projections, U-dual to the standard ones.

Graña, Mariana; Triendl, Hagen

2013-03-01

152

Hamiltonian BRST deformation of a class of n-dimensional BF-type theories

Consistent Hamiltonian interactions that can be added to an abelian free BF-type class of theories in any n greater or equal to 4 spacetime dimensions are constructed in the framework of the Hamiltonian BRST deformation based on cohomological techniques. The resulting model is an interacting field theory in higher dimensions with an open algebra of on-shell reducible first-class constraints. We argue that the Hamiltonian couplings are related to a natural structure of Poisson manifold on the target space.

Bizdadea, C; Cioroianu, E M; Saliu, S O; Sararu, S C

2003-01-01

153

(NS5,Dp) and (NS5,D(p+2),Dp) bound states of type IIB and type IIA string theories

International Nuclear Information System (INIS)

Starting from the (q,p) 5-brane solution of type IIB string theory, we here construct the low energy configuration corresponding to (NS5,Dp)-brane bound states (for 0?p?4) using the T-duality map between type IIB and type IIA string theories. We use the SL(2,Z) symmetry on the type IIB bound state (NS5,D3) to construct (NS5,D5,D3) bound state. We then apply T-duality transformation again on this state to construct the bound states of the form (NS5,D(p+2),Dp) (for 0?p?2) of both type IIB and type IIA string theories. We give the tension formula for these states and show that they form non-threshold bound states. All these states preserve half of the space-time supersymmetries of string theories. We also briefly discuss the ODp-limits corresponding to (NS5,Dp) bound state solutions. (author)

154

DEFF Research Database (Denmark)

In present study, different types of infectious bursal disease virus (IBDV), virulent strain DK01, classic strain F52/70 and vaccine strain D78 were quantified and detected in infected bursa of Fabricius (BF) and cloacal swabs using quantitative real time RT-PCR with SYBR green dye. For selection of a suitable internal control gene, real time PCR parameters were evaluated for three candidate genes, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), 28S rRNA and beta-actin to IBDVs. Based on this P-actin was selected as an internal control for quantification of IBDVs in BF. All BF samples with D78, DK01 or F52/70 inoculation were detected as virus positive at day I post inoculation (p.i.). The D78 viral load peaked at day 4 and day 8 p.i., while the DK01 and F52/70 viral load showed relatively high levels at day 2 p.i. In cloacal swabs, viruses detectable were at day 2 p.i. for DK01 and F52/70, day 8 p.i. for D78. Importantly, the primers set were specific as the D78 primer set gave no amplification of F52/70 and DK01 and the DK01 primer set gave no amplification of D78, thus DK01 and D78 could be quantified simultaneously in dually infected chickens by use of these two set of primers. The method described here is robust and may sever as a useful tool with high capacity for diagnostics as well as in viral pathogenesis studies.

Li, Yiping; Kabell, Susanne

2007-01-01

155

International Nuclear Information System (INIS)

The effective-mean-field (EMF) theory, consisting of Mori-Tanaka's mean-field theory and Bruggeman's effective medium approximation, was extended in order to calculate the coefficients of thermal expansion (CTE) of composite materials. The effective elastic constants and CTE of lotus-type porous metals, possessing cylindrical pores aligned unidirectionally, were evaluated with the EMF theory

156

Type IIB string theory on $AdS_{5}xT^{nn'}$

We study \\kk spectrum of type IIB string theory compactified on $AdS_5 \\times T^{nn'}$ in the context of AdS/CFT correspondence. We examine some of the modes of the complexified 2 form potential as an example and show that for the states at the bottom of the \\kk tower the corresponding d=4 boundary field operators have rational conformal dimensions. The masses of some of the fermionic modes in the bottom of each tower as functions of the R charge in the boundary conformal theory are also rational. Furthermore the modes in the bottom of the towers originating from q forms on $T^{11}$ can be put in correspondence with the BRS cohomology classes of the c=1 non critical string theory with ghost number q.

Jatkar, D P; Jatkar, Dileep P.

1999-01-01

157

Type IIA/M-theory Moduli fixing in a Class of Orientifold Models

We present the study of type II A flux vacua and their M-theory duals for compactification on a class of Calabi-Yau orientifolds. The Kahler potential is derived from toroidal compactifications and the superpotential contains a contribution from non-Abelian gauge degrees of freedoms. We obtain complete stabilisation of the moduli. We found one supersymmetric minimum and several non supersymmetric ones. Consistency of the analysis constrains the parameters of the models in a finite region containing a finite, although very large, number of flux vacua. From the M-theory side, we found some differences in the distributions of the physical quantities with respect to the M-theory ensemble studied by Acharya et al. In particular, it is easier to find small supersymmetry breaking scale.

Milanesi, Giuseppe

2007-01-01

158

Deformed type 0A matrix model and super-Liouville theory for fermionic black holes

International Nuclear Information System (INIS)

We consider a c-circumflex = 1 model in the fermionic black hole background. For this purpose we consider a model which contains both the N 1 and the N = 2 super-Liouville interactions. We propose that this model is dual to a recently proposed type 0A matrix quantum mechanics model with vortex deformations. We support our conjecture by showing that non-perturbative corrections to the free energy computed by both the matrix model and the super-Liouville theories agree exactly by treating the N = 2 interaction as a small perturbation. We also show that a two-point function on sphere calculated from the deformed type 0A matrix model is consistent with that of the N = 2 super-Liouville theory when the N = 1 interaction becomes small. This duality between the matrix model and super-Liouville theories leads to a conjecture for arbitrary n-point correlation functions of the N = 1 super-Liouville theory on the sphere

159

A sufficient condition for de Sitter vacua in type IIB string theory

International Nuclear Information System (INIS)

We derive a sufficient condition for realizing meta-stable de Sitter vacua with small positive cosmological constant within type IIB string theory flux compactifications with spontaneously broken supersymmetry. There are a number of 'lamp post' constructions of de Sitter vacua in type IIB string theory and supergravity. We show that one of them - the method of 'Kaehler uplifting' by F-terms from an interplay between non-perturbative effects and the leading ?'-correction - allows for a more general parametric understanding of the existence of de Sitter vacua. The result is a condition on the values of the flux induced superpotential and the topological data of the Calabi-Yau compactification, which guarantees the existence of a meta-stable de Sitter vacuum if met. Our analysis explicitly includes the stabilization of all moduli, i.e. the Kaehler, dilaton and complex structure moduli, by the interplay of the leading perturbative and non-perturbative effects at parametrically large volume. (orig.)

160

Kaluza–Klein-type models of de Sitter and Poincaré gauge theories of gravity

International Nuclear Information System (INIS)

We construct Kaluza–Klein-type models with a de Sitter or Minkowski bundle in the de Sitter or Poincaré gauge theory of gravity, respectively. A manifestly gauge-invariant formalism has been given. The gravitational dynamics is constructed by the geometry of the de Sitter or Minkowski bundle and a global section which plays an important role in the gauge-invariant formalism. Unlike the old Kaluza–Klein-type models of gauge theory of gravity, a suitable cosmological term can be obtained in the Lagrangian of our models and the models in the spin-current-free and torsion-free limit will come back to general relativity with a corresponding cosmological term. We also generalize the results to the case with a variable cosmological term. (paper)

161

Numerical knot invariants of finite type from Chern-Simons perturbation theory

International Nuclear Information System (INIS)

Chern-Simons gauge theory for compact semisimple groups is analyzed from a perturbation theory point of view. The general form of the perturbative series expansion of a Wilson line is presented in terms of the Casimir operators of the gauge group. From this expansion new numerical knot invariants are obtained. These knot invariants turn out to be of finite type (Vassiliev invariants) and to possess an integral representation. Using known results about Jones, HOMFLY, Kauffman and Akutsu-Wadati polynomial invariants these new knot invariants are computed up to type six for all prime knots up to six crossings. Our results suggest that these knot invariants can be normalized in such a way that they are integer-valued. ((orig.))

162

Bianchi type VI1 cosmological model with wet dark fluid in scale invariant theory of gravitation

In this paper, we have investigated Bianchi type VIh, II and III cosmological model with wet dark fluid in scale invariant theory of gravity, where the matter field is in the form of perfect fluid and with a time dependent gauge function (Dirac gauge). A non-singular model for the universe filled with disorder radiation is constructed and some physical behaviors of the model are studied for the feasible VIh (h = 1) space-time.

Mishra, B

2014-01-01

163

Transient theory of double slope floating cum tilted - wick type solar still

International Nuclear Information System (INIS)

A double slope floating cum tilted-wick solar still has been fabricated and transient theory of floating cum tilted-wick type solar still has been proposed. Analytical expressions have been derived for the different temperatures components of the proposed system. For elocution of the analytical results, numerical calculations have been carried out using the meteorological parameters for a typical summer day in Coimbatore. Analytical expression results are found to be in the close agreement with the experimental results. (authors)

164

In this paper we show that Ultradistributions of Exponential Type (UET) are appropriate for the description in a consistent way world sheet superstring and superstring field theories. A new Lagrangian for the closed world sheet superstring is obtained. We also show that the superstring field is a linear superposition of UET of compact support (CUET), and give the notion of anti-superstring. We evaluate the propagator for the string field, and calculate the convolution of two of them.

Bollini, C G; Rocca, M C

2008-01-01

165

Three-dimensional theory of quantum memories based on Lambda-type atomic ensembles

Digital Repository Infrastructure Vision for European Research (DRIVER)

We develop a three-dimensional theory for quantum memories based on light storage in ensembles of Lambda-type atoms, where two long-lived atomic ground states are employed. We consider light storage in an ensemble of finite spatial extent and we show that within the paraxial approximation the Fresnel number of the atomic ensemble and the optical depth are the only important physical parameters determining the quality of the quantum memory. We analyze the influence of these p...

Zeuthen, Emil; Grodecka-grad, Anna; Sørensen, Anders S.

2011-01-01

166

Tilted Bianchi Type VI0 Cosmological Model in Saez and Ballester Scalar Tensor Theory of Gravitation

Directory of Open Access Journals (Sweden)

Full Text Available Tilted Bianchi type VI0 cosmological model is investigated in a new scalar tensor theory of gravitation pro-posed by Saez and Ballester (Physics Letters A 113:467, 1986. Exact solutions to the field equations are derived when the metric potentials are functions of cosmic time only. Some physical and geometrical proper-ties of the solutions are also discussed.

Subrata Kumar Sahu

2010-05-01

167

LRS Bianchi Type-I Universe in Barber's Second Self Creation Theory

We consider Barber’s second self creation theory with perfect fluid source for an LRS Bianchi type-I metric by using deceleration parameter to be time dependent where the metric potentials are taken as function of x and t. The present models are free from singularity and the results are consistent within the observational limit. Some physical properties of the models are also discussed.

Pradhan, Anirudh; Agarwal, Shilpi; Singh, G. P.

2009-01-01

168

LRS Bianchi Type-I Cosmological Models in Barber's Second Self Creation Theory

Barber's second self creation theory with perfect fluid source for an LRS Bianchi type-I metric is considered using deceleration parameter to be constant where the metric potentials are taken as functions of x and t. In particular, some exact solutions have also been obtained for the vacuum universe, Zel'dovich universe and radiation universe. Some physical properties of the models are also discussed.

Pradhan, Anirudh; Vishwakarma, Anil Kumar; Dolgov, A.

169

Five dimensional LRS Bianchi type-I string cosmological model in Saez and Ballester theory

In this paper, it is shown that five dimensional LRS Bianchi type-I string cosmological models do not survive for Geometric and Takabayasi string whereas Barotropic string i.e. ?= ?( ?) survives and degenerates string with ?+ ?=0 in scalar tensor theory of gravitation proposed by Saez and Ballester (Phys. Lett. A 113:467, 1986). Further we studied some physical and geometrical properties of the model.

Mohanty, G.; Sahoo, R. R.; Mahanta, K. L.

2007-12-01

170

On Energy and Entropy Influxes in the Green-Naghdi Type III Theory of Heat Conduction

Digital Repository Infrastructure Vision for European Research (DRIVER)

The energy-influx/entropy-influx relation in the Green-Naghdi Type III theory of heat conduction is examined within a thermodynamical framework \\`a la Mueller-Liu, where that relation is not specified a priori irrespectively of the constitutive class under attention. It is shown that the classical assumption, i.e., that the entropy influx and the energy influx are proportional via the absolute temperature, holds true if heat conduction is, in a sense that is made precise, is...

Bargmann, Swantje; Favata, Antonino; Podio-guidugli, Paolo

2012-01-01

171

Flux vacua in Dirac-Born-Infeld type Einstein-Maxwell theory

We study compactification of extra dimensions in a theory of Dirac-Born-Infeld (DBI) type gravity. We investigate the solution for Minkowski spacetime with an $S^{2}$ extra space. The solution is derived by the effective potential method in the presence of the magnetic flux on the extra sphere. We find that, in a certain model, the radius of the extra space has a minimum value independent of the higher-dimensional Newton constant in weak-field limit.

Maki, Takuya; Kobayashi, Koichiro; Shiraishi, Kiyoshi

2011-01-01

172

Two-dimensional interactions between a BF-type theory and a collection of vector fields

Consistent interactions that can be added to a two-dimensional, free abelian gauge theory comprising a special class of BF-type models and a collection of vector fields are constructed from the deformation of the solution to the master equation based on specific cohomological techniques. The deformation procedure modifies the Lagrangian action, the gauge transformations, as well as the accompanying algebra of the interacting model.

Cioroianu, E M

2004-01-01

173

Spatially Homogeneous Bianchi Type V Cosmological Model in the Scale-Covariant Theory of Gravitation

International Nuclear Information System (INIS)

We discuss spatially homogeneous and anisotropic Bianchi type-V spacetime filled with a perfect fluid in the framework of the scale-covariant theory of gravitation proposed by Canuto et al. By applying the law of variation for Hubble's parameter, exact solutions of the field equations are obtained, which correspond to the model of the universe having a big-bang type singularity at the initial time t = 0. The cosmological model, evolving from the initial singularity, expands with power-law expansion and gives essentially an empty space for a large time. The physical and dynamical properties of the model are also discussed. (geophysics, astronomy, and astrophysics)

174

Universality of oscillation theory laws. types and role of mathematical models

Directory of Open Access Journals (Sweden)

Full Text Available The universality of oscillation theory laws is discussed. It is suggested that all models of concrete systems be separated into four categories: models Ã¢Â€Â“ Ã¢Â€ÂœportraitsÃ¢Â€Â of investigated systems, models of the type of Ã¢Â€Âœblack boxÃ¢Â€Â, aggregating models, and models of certain phenomena which can occur in real systems. As an example of the model of the fourth type, the equation of oscillations of a pendulum with a randomly vibrating suspension axis is considered for the purpose of clarifying the mechanism of the transition to turbulence.

Polina S. Landa

1996-01-01

175

Matrix Models, Integrable Structures, and T-duality of Type 0 String Theory

Instanton matrix models (IMM) for two dimensional string theories are obtained from the matrix quantum mechanics (MQM) of the T-dual theory. In this paper we study the connection between the IMM and MQM, which amounts to understand T-duality from the viewpoint of matrix models. We show that type 0A and type 0B matrix models perturbed by purely closed string momentum modes (or purely winding modes) have the integrable structure of Toda hierarchies, extending the well known results for c=1 string. In particular, we show that type 0A(0B) MQM perturbed by momentum modes has the same integrable structure as type 0B(0A) MQM perturbed by winding modes, which is a nontrivial check of the T-duality between the matrix models. The MQM deformed by NS-NS winding modes are used to study type 0 string in 2D black holes. We also find an intriguing connection between the IMM and the MQM via tachyon condensation. The array of alternating D-instantons and anti-D-instantons separated at the critical distance plays a key role in ...

Yin, X

2003-01-01

176

Quantification of margins and uncertainties: Alternative representations of epistemic uncertainty

Energy Technology Data Exchange (ETDEWEB)

In 2001, the National Nuclear Security Administration of the U.S. Department of Energy in conjunction with the national security laboratories (i.e., Los Alamos National Laboratory, Lawrence Livermore National Laboratory and Sandia National Laboratories) initiated development of a process designated Quantification of Margins and Uncertainties (QMU) for the use of risk assessment methodologies in the certification of the reliability and safety of the nation's nuclear weapons stockpile. A previous presentation, 'Quantification of Margins and Uncertainties: Conceptual and Computational Basis,' describes the basic ideas that underlie QMU and illustrates these ideas with two notional examples that employ probability for the representation of aleatory and epistemic uncertainty. The current presentation introduces and illustrates the use of interval analysis, possibility theory and evidence theory as alternatives to the use of probability theory for the representation of epistemic uncertainty in QMU-type analyses. The following topics are considered: the mathematical structure of alternative representations of uncertainty, alternative representations of epistemic uncertainty in QMU analyses involving only epistemic uncertainty, and alternative representations of epistemic uncertainty in QMU analyses involving a separation of aleatory and epistemic uncertainty. Analyses involving interval analysis, possibility theory and evidence theory are illustrated with the same two notional examples used in the presentation indicated above to illustrate the use of probability to represent aleatory and epistemic uncertainty in QMU analyses.

Helton, Jon C., E-mail: jchelto@sandia.gov [Department of Mathematics and Statistics, Arizona State University, Tempe, AZ 85287-1804 (United States); Johnson, Jay D. [ProStat, Mesa, AZ 85204-5326 (United States)

2011-09-15

177

International Nuclear Information System (INIS)

To the full order in fermions, we construct D=10 type II supersymmetric double field theory. We spell the precise N=2 supersymmetry transformation rules as for 32 supercharges. The constructed action unifies type IIA and IIB supergravities in a manifestly covariant manner with respect to O(10,10) T-duality and a pair of local Lorentz groups, or Spin(1,9)×Spin(9,1), besides the usual general covariance of supergravities or the generalized diffeomorphism. While the theory is unique, the solutions are twofold. Type IIA and IIB supergravities are identified as two different types of solutions rather than two different theories

178

Directory of Open Access Journals (Sweden)

Full Text Available Traditional theory of mind accounts of social cognition have been at the basis of most studies in the social cognitive neurosciences. However, in recent years, the need to go beyond traditional theory of mind accounts for understanding real life social interactions has become all the more pressing. At the same time it remains unclear whether alternative accounts, such as interactionism, can yield a sufficient description and explanation of social interactions. We argue that instead of considering theory of mind and interactionism as mutually exclusive opponents, they should be integrated into a more comprehensive account of social cognition. We draw on dual process models of social cognition that contrast two different types of social cognitive processing. The first type (labelled Type 1 refers to processes that are fast, efficient, stimulus-driven, and relatively inflexible. The second type (labelled Type 2 refers to processes that are relatively slow, cognitively laborious, flexible, and may involve conscious control. We argue that while interactionism captures aspects of social cognition mostly related to Type 1 processes, theory of mind is more focused on those based on Type 2 processes. We suggest that real life social interactions are rarely based on either Type 1 or Type 2 processes alone. On the contrary, we propose that in most cases both types of processes are simultaneously involved and that social behaviour may be sustained by the interplay between these two types of processes. Finally, we discuss how the new integrative framework can guide experimental research on social interaction.

VivianBohl

2012-10-01

179

Non-renormalisation Conditions in Type II String Theory and Maximal Supergravity

This paper considers general features of the derivative expansion of Feynman diagram contributions to the four-graviton scattering amplitude in eleven-dimensional supergravity compactified on a two-torus. These are translated into statements about interactions of the form D^{2k} R^4 in type II superstring theories, assuming the standard M-theory/string theory duality relationships, which provide powerful constraints on the effective interactions. In the ten-dimensional IIA limit we find that there can be no perturbative contributions beyond k string loops (for k>0). Furthermore, the genus h=k contributions are determined exactly by the one-loop eleven-dimensional supergravity amplitude for all values of k. To the extent that these results reflect exact properties of M-theory, they indicate that low energy maximally extended supergravity at h loops only has power-behaved ultraviolet divergences in dimensions d > 4 + 6/h, the same bound as for N=4 Yang--Mills. This implies that four-dimensional N=8 supergravity...

Green, M B; Vanhove, P; Green, Michael B.; Russo, Jorge G.; Vanhove, Pierre

2007-01-01

180

Type and structure of time-like singularities in general relativity theory

International Nuclear Information System (INIS)

A method is proposed which permits one to deterMine whether a time-like singularity refers to a point, linear or some other type of gravitational field singularity. It is shown that in the general theory of relativity an altogether different type of source may be possible which does not have any analogs in finite curvature space. An analysis is made of a number of solutions containing time-like singularities whose type varies depending on the sign of the functions involved in the solutions. The form of the solution near simple linear sources and of generalized anisotropic solutions is determined more accurately. The space-time described by the ?-metric is investigated completely and the form of the metric near the ends and at singular points of linear Weyl singularities is found

181

Acute and chronic infections of the seminal tract are among the most common causes of male infertility. As at least half of male infertility cases are classified as idiopathic, some of these cases might be attributed to asymptomatic infection. The detection and quantification of Epstein-Barr virus (EBV), cytomegalovirus (CMV) and human herpes virus type 6 (HHV-6) DNA in semen samples were performed. A total of 232 patients were divided into five groups: (i) infertile men with varicocoele; (ii) men with idiopathic infertility; (iii) infertile men with chronic inflammatory urogenital tract diseases (IUTD); (iv) fertile men with IUTD and (v) men whose partners had a history of pregnancy loss. In the study population, the prevalence of viral DNA was 17.7, 3.4% for EBV, 5.2% for CMV, 6.5% for HHV-6, 0.43% for EBV + CMV, 0.87% for EBV + HHV-6 and 1.3% for CMV + HHV-6. The median viral loads for EBV, CMV and HHV-6 were 500, 2250 and 250 copies/mL respectively. Of the sperm cell fractions, derived from infected samples 87.5% contained viral DNA. No association between EBV and fertility disorders or IUTD was found. CMV detection was much higher in the group of patients with infertility and concomitant IUTD compared with the other groups combined (18.5% vs. 5.4%, p = 0.03) and associated with reduced sperm cell count (39.5 × 10(6) /mL vs. 72.5 × 10(6) /mL, p = 0.036). Immunostaining of spermatozoa from infected samples and in vitro-infected cells detected CMV in sperm heads, tails and connecting pieces and revealed attachment to sperm membrane and intracellular localization. HHV-6 was the more common in fertile men with chronic IUTD than in the other groups combined (19% vs. 6.3%, p = 0.018) and had no effect on sperm parameters. The results suggest that both CMV and HHV-6 may contribute to the aetiology of IUTD and, moreover, CMV-associated IUTD can lead to male sterility. PMID:24903066

Naumenko, V; Tyulenev, Y; Kurilo, L; Shileiko, L; Sorokina, T; Evdokimov, V; Yakovleva, V; Kovalyk, V; Malolina, E; Kulibin, A; Gomberg, M; Kushch, A

2014-09-01

182

(NS5,Dp) and (NS5,D(p+2),Dp) bound states of type IIB and type IIA string theories

Digital Repository Infrastructure Vision for European Research (DRIVER)

Starting from the (q,p) 5-brane solution of type IIB string theory, we here construct the low energy configuration corresponding to (NS5,Dp)-brane bound states (for $0\\leq p\\leq 4$) using the T-duality map between type IIB and type IIA string theories. We use the SL(2,Z) symmetry on the type IIB bound state (NS5,D3) to construct (NS5,D5,D3) bound state. We then apply T-duality transformation again on this state to construct the bound states of the form (NS5,D(p+2),Dp) (for $...

Mitra, Indranil; Roy, Shibaji

2000-01-01

183

Quantification analysis of CT of ovarian tumors

International Nuclear Information System (INIS)

Early symptoms in patients with ovarian tumors are usually few and nonspecific. CT is often very helpful in the diagnosis of ovarian tumors. Although it is difficult to identify normal ovaries, it is usually possible to diagnose ovarian lesions on CT, because with few exceptions they show tumorous enlargement. We can even estimate the histology in typical cases such as dermoid cysts or some types of cystadenomas. However, estimation of histology is difficult in many cases. Tumors other than those of ovarian origin can occur in the pelvis and require differentiation. Ovarian tumors have a close relationship with the uterus and broad ligaments, and make contact with as least one side of the pelvic wall. Enhanced CT with contrast media may facilitate differentiation between pedunculated subserosal leiomyoma uteri and ovarian tumor, because the former shows intense enhancement as a uterine body; the latter is less intense. Thus, we have little difficulty in differentiating between tumors of ovarian origin and those of other origins. Our problem is differentiating between malignant and benign ovarian tumors, and clarification of their histology. In this study, we devised a decision flow chart to attain an accurate diagnosis. In part, we have utilized Hayashi's quantification theory II, a multiple regression analysis where predictive variables are categorical and outside criteria are classificatory. Hayashi stated that the aim of multi-dimensional quantification is to synthetically form numerical representation of intercorrelated patterns to maximize the efficiency of classification, i.e. the success rate of prediction. Thus, quantification of patterns is thought to be effective in facilitating image diagnosis such as CT and minimizing errors. (author)

184

On power-type cosmological solutions of the Brans-Dicke theory

International Nuclear Information System (INIS)

Analysis of power-type cosmological solutions of the Brans-Dicke theory (BDT) is carried out. The observed data testify to the fact that the real Universe, beginning from the stage preceding nucleon synthesis and up-to nowadays, should be described either by Friedman or cosmological solutions in the form of rather similar to them. In the BDT such solutions are those, which transfer at free parameter values ? ? infinity into Friedman ones. The rest solutions can be considered as nonphysical ones. The BDT is shown to disagree fully with the Mach principle

185

Volume Stabilization via $\\alpha^\\prime$ Corrections in Type IIB Theory with Fluxes

We consider the Type IIB string theory in the presence of various extra $7/\\bar 7$-brane pairs compactified on a warped Calabi-Yau three-fold that admits a conifold singularity. We demonstrate that the volume modulus can be stabilized perturbatively at a non-supersymmetric $AdS_4/dS_4$ vacuum by the effective potential that includes the stringy $(\\alpha^\\prime)^3$ correction obtained by Becker {\\it et al.} together with a combination of positive tension and anomalous negative tension terms generated by the additional 7-brane-antibrane pairs.

Bobkov, K

2005-01-01

186

S-matrix elements and covariant tachyon action in type 0 theory

International Nuclear Information System (INIS)

We evaluate the sphere level S-matrix element of two tachyons and two massless NS states, the S-matrix element of four tachyons, and the S-matrix element of two tachyons and two Ramond-Ramond vertex operators, in type 0 theory. We then find an expansion for theses amplitudes that their leading order terms correspond to a covariant tachyon action. To the order considered, there are no T4, T2(-bar T)2, T2H2, nor T2R tachyon couplings, whereas, the tachyon couplings FF-bar T and T2F2 are non-zero

187

Comment on the one-loop finiteness in type-I superstring theory

International Nuclear Information System (INIS)

By using the Pauli-Villars method, one-loop divergence of the 4-point amplitude in SO(N) type-I superstring theory is studied. If one assigns the equal mass to the Pauli-Villars regulators appearing in the planar and nonorientable diagrams, the one-loop finiteness does not hold for N = 32. From the present view point, the principal-part prescription by Green and Schwarz corresponds to the different regulator mass assignment for the planar and nonorientable diagrams. (author)

188

LRS Bianchi type-II dark energy model in a scalar-tensor theory of gravitation

A locally rotationally symmetric Bianchi type-II (LRS B-II) space-time with variable equation of state (EoS) parameter and constant deceleration parameter have been investigated in the scalar-tensor theory proposed by Saez and Ballester (Phys. Lett. A 113:467, 1986). The scalar-tensor field equations have been solved by applying variation law for generalized Hubble's parameter given by Bermann (Nuovo Cimento 74:182, 1983). The physical and kinematical properties of the model are also discussed.

Naidu, R. L.; Satyanarayana, B.; Reddy, D. R. K.

2012-04-01

189

Bianchi type-II Bulk viscous string cosmological model in self-creation theory of gravitation

A spatially homogeneous and anisotropic LRS Bianchi type-II space-time is considered in the frame work of second self-creation theory of gravitation proposed by Barber (Gen. Relativ. Gravit. 14:117, 1982) in the presence of bulk viscous fluid containing one dimensional cosmic strings. A determinate solution of the field equations is presented using special variation for Hubble's parameter given by Berman (Nuovo Cimento B 74:182, 1983) and some physically plausible conditions. The solution represents a bulk viscous string model in the second self-creation cosmology. We have also discussed some physical and kinematical properties of the model.

Reddy, D. R. K.; Bhaskara Rao, M. P. V. V.; Sobhan Babu, K.

2014-05-01

190

Bianchi types I and V bulk viscous fluid cosmological models in f( R, T) gravity theory

In this paper we present non-singular Bianchi types I and V cosmological models, in the presence of bulk viscous fluid and within the framework of f(R,T) gravity theory. Exact solutions to the field equations are obtained by choosing a particular form of the function f(R,T) and a special value for the average scale factor of the model, which corresponds to a time- dependent deceleration parameter. The cosmological models initially accelerate for a certain period of time and thereafter decelerate. The physical and kinematical properties of the models of the universe are discussed.

Ram, Shri; Kumari, Priyanka

2014-10-01

191

Total reflection X-ray fluorescence (TXRF) is a very promising method for the direct, quick and reliable multi-elemental quantification of trace elements in protein samples. With the introduction of an internal standard consisting of two reference elements, scandium and gallium, a wide range of proteins can be analyzed, regardless of their salt content, buffer composition, additives and amino acid composition. This strategy also enables quantification of matrix effects. Two potential issues associated with drying have been considered in this study: (1) Formation of heterogeneous residues of varying thickness and/or density; and (2) separation of the internal standard and protein during drying (which has to be prevented to allow accurate quantification). These issues were investigated by microbeam X-ray fluorescence (?XRF) with special emphasis on (I) the influence of sample support and (II) the protein / buffer system used. In the first part, a model protein was studied on well established sample supports used in TXRF, PIXE and XRF (Mylar, siliconized quartz, Plexiglas and silicon). In the second part we imaged proteins of different molecular weight, oligomerization state, bound metals and solubility. A partial separation of protein and internal standard was only observed with untreated silicon, suggesting it may not be an adequate support material. Siliconized quartz proved to be the least prone to heterogeneous drying of the sample and yielded the most reliable results.

Wellenreuther, G.; Fittschen, U. E. A.; Achard, M. E. S.; Faust, A.; Kreplin, X.; Meyer-Klaucke, W.

2008-12-01

192

LRS Bianchi Type-I Dark Energy Cosmological Model in Brans-Dicke Theory of Gravitation

Bianchi type-I dark energy model with variable equation of state (EoS) parameter is presented in a scalar-tensor theory of gravitation proposed by Brans and Dicke (Phys. Rev. 124:925, 1961). To get a determinate solution of the field equations we will take the help of special law of variation for Hubble's parameter presented by Bermann (Nuovo Cimento B. 74:182, 1983) which yields a dark energy cosmological model with negative constant deceleration parameter. It is observed that this dark energy cosmological model always represents an accelerated and expanding universe and also consistent with the recent observations of type-Ia supernovae. Some physical and geometrical properties of the model are also discussed.

Rao, V. U. M.; Vijaya Santhi, M.; Vinutha, T.; Sree Devi Kumari, G.

2012-10-01

193

International Nuclear Information System (INIS)

It is well accepted that textures in polycrystalline films have significant effects on film properties. The magnetoelectric (ME) coupling in a 2-2-type multiferroic composite film was theoretically discussed using Landau-Ginsburg-Devonshire theory, where the influences of dispersive texture and residual stress were considered. As an example, the 2-2-type CoFe2O4/BaTiO3 composite film was theoretically analysed, wherein the case of both the magnetostrictive phase and the piezoelectric phase with (0 0 1)-oriented texture was considered. Our results show that the ME coupling is enhanced with the texture degree of the piezoelectric phase and/or the magnitude of the residual tensile stress, but weakened with the magnitude of residual compressive stress. With increasing texture degree of the magnetostrictive phase, the ME coupling is enhanced when the texture degree is smaller than a critical value, but weakened when the texture degree is larger than the critical value

194

Maier-Saupe-type theory of ferroelectric nanoparticles in nematic liquid crystals.

Several experiments have reported that ferroelectric nanoparticles have drastic effects on nematic liquid crystals-increasing the isotropic-nematic transition temperature by about 5 K, and greatly increasing the sensitivity to applied electric fields. In a recent paper [Lopatina and Selinger, Phys. Rev. Lett. 102, 197802 (2009)], we modeled these effects through a Landau theory, based on coupled orientational order parameters for the liquid crystal and the nanoparticles. This model has one important limitation: Like all Landau theories, it involves an expansion of the free energy in powers of the order parameters, and hence it overestimates the order parameters that occur in the low-temperature phase. For that reason, we now develop a new Maier-Saupe-type model, which explicitly shows the low-temperature saturation of the order parameters. This model reduces to the Landau theory in the limit of high temperature or weak coupling, but shows different behavior in the opposite limit. We compare these calculations with experimental results on ferroelectric nanoparticles in liquid crystals. PMID:22181153

Lopatina, Lena M; Selinger, Jonathan V

2011-10-01

195

On the effective theory of type II string compactifications on nilmanifolds and coset spaces

Energy Technology Data Exchange (ETDEWEB)

In this thesis we analyzed a large number of type IIA strict SU(3)-structure compactifications with fluxes and O6/D6-sources, as well as type IIB static SU(2)-structure compactifications with fluxes and O5/O7-sources. Restricting to structures and fluxes that are constant in the basis of left-invariant one-forms, these models are tractable enough to allow for an explicit derivation of the four-dimensional low-energy effective theory. The six-dimensional compact manifolds we studied in this thesis are nilmanifolds based on nilpotent Lie-algebras, and, on the other hand, coset spaces based on semisimple and U(1)-groups, which admit a left-invariant strict SU(3)- or static SU(2)-structure. In particular, from the set of 34 distinct nilmanifolds we identified two nilmanifolds, the torus and the Iwasawa manifold, that allow for an AdS{sub 4}, N = 1 type IIA strict SU(3)-structure solution and one nilmanifold allowing for an AdS{sub 4}, N = 1 type IIB static SU(2)-structure solution. From the set of all the possible six-dimensional coset spaces, we identified seven coset spaces suitable for strict SU(3)-structure compactifications, four of which also allow for a static SU(2)-structure compactification. For all these models, we calculated the four-dimensional low-energy effective theory using N = 1 supergravity techniques. In order to write down the most general four-dimensional effective action, we also studied how to classify the different disconnected ''bubbles'' in moduli space. (orig.)

Caviezel, Claudio

2009-07-30

196

Digital Repository Infrastructure Vision for European Research (DRIVER)

A single G-to-T missense mutation in the gene for the JAK2 tyrosine kinase, leading to a V617F amino acid substitution, is commonly found in several myeloproliferative neoplasms. Reliable quantification of this mutant allele is of increasing clinical and therapeutic interest in predicting and diagnosing this group of neoplasms. Because JAK2V617F is somatically acquired and may be followed by loss of heterozygosity, the percentage of mutant versus wild-type DNA in blood can vary between 0% and...

Huijsmans, Cornelis J. J.; Poodt, Jeroen; Savelkoul, Paul H. M.; Hermans, Mirjam H. A.

2011-01-01

197

M-theory/type IIA duality and K3 in the Gibbons-Hawking approximation

We review the geometry of K3 surfaces and then describe this geometry from the point of view of an approximate metric of Gibbons-Hawking form. This metric arises from the M-theory lift of the tree-level supergravity description of type IIA string theory on the T^3/Z_2 orientifold, the D6/O6 orientifold T-dual to type I on T^3. At large base, it provides a good approximation to the exact K3 metric everywhere except in regions that can be made arbitrarily small. The metric is hyperk\\"ahler, and we give explicit expressions for the hyperk\\"ahler forms as well as harmonic representatives of all cohomology classes. Finally we compute the metric on the moduli space of approximate metrics in two ways, first by projecting to transverse traceless deformations (using compensators), and then by computing the naive moduli space metric from dimensional reduction. In either case, we find agreement with the exact coset moduli space of K3 metrics. The T^3/Z_2 orientifold provides a simple example of a warped compactification...

Schulz, Michael B

2012-01-01

198

Mirage Models Confront the LHC: II. Flux-Stabilized Type IIB String Theory

We continue the study of a class of string-motivated effective supergravity theories in light of current data from the CERN Large Hadron Collider (LHC). In this installment we consider Type IIB string theory compactified on a Calabi-Yau orientifold in the presence of fluxes, in the manner originally formulated by Kachru, et al. We allow for a variety of potential uplift mechanisms and embeddings of the Standard Model field content into D3 and D7 brane configurations. We find that an uplift sector independent of the Kahler moduli, as is the case with anti-D3 branes, is inconsistent with data unless the matter and Higgs sectors are localized on D7 branes exclusively, or are confined to twisted sectors between D3 and D7 branes. We identify regions of parameter space for all possible D-brane configurations that remain consistent with PLANCK observations on the dark matter relic density and measurements of the CP-even Higgs mass at the LHC. Constraints arising from LHC searches at 8 TeV center-of-mass energies, an...

Kaufman, Bryan

2013-01-01

199

Brane Curvature Corrections to the $\\mathcal{N}=1$ Type II/F-theory Effective Action

We initiate a study of corrections to the K\\"{a}hler potential of $\\mathcal{N}=1$ type II/F-theory compactifications that arise from curvature terms in the action of D-branes and orientifold planes. We first show that a recently proposed correction, which was argued to appear at order $\\alpha^{\\prime 2}g_s$ and be proportional to the intersection volume of D7-branes and O7-planes, is an artifact of an inconvenient field basis in the dual M-theory frame and can be removed by a field redefinition. We then analyze to what extent curvature terms in the DBI and WZ action may still lead to corrections of a similar kind and identify two general mechanisms that can potentially modify the volume dependence of the K\\"{a}hler potential in the presence of D-branes and O-planes. The first mechanism is related to an induced Einstein-Hilbert term on warped brane worldvolumes, which leads to a shift in the classical volume of the compactification manifold. The resulting corrections are generic and can appear at one-loop orde...

Junghans, Daniel

2014-01-01

200

Engineering of Quantum Hall Effect from type IIA string theory on the K3 surface

International Nuclear Information System (INIS)

Using D-brane configurations on the K3 surface, we give six-dimensional type IIA stringy realizations of the Quantum Hall Effect (QHE) in 1+2 dimensions. Based on the vertical and horizontal lines of the K3 Hodge diamond, we engineer two different stringy realizations. The vertical line presents a realization in terms of D2 and D6-branes wrapping the K3 surface. The horizontal one is associated with hierarchical stringy descriptions obtained from a quiver gauge theory living on a stack of D4-branes wrapping intersecting 2-spheres embedded in the K3 surface with deformed singularities. These geometries are classified by three kinds of the Kac-Moody algebras: ordinary, i.e. finite dimensional, affine and indefinite. We find that no stringy QHE in 1+2 dimensions can occur in the quiver gauge theory living on intersecting 2-spheres arranged as affine Dynkin diagrams. Stringy realizations of QHE can be done only for the finite and indefinite geometries. In particular, the finite Lie algebras give models with fractional filling fractions, while the indefinite ones classify models with negative filling fractions which can be associated with the physics of holes in the graphene.

201

Mirage models confront the LHC. II. Flux-stabilized type IIB string theory

We continue the study of a class of string-motivated effective supergravity theories in light of current data from the CERN Large Hadron Collider (LHC). In this installment we consider type IIB string theory compactified on a Calabi-Yau orientifold in the presence of fluxes, in the manner originally formulated by Kachru et al. We allow for a variety of potential uplift mechanisms and embeddings of the Standard Model field content into D3-and D7-brane configurations. We find that an uplift sector independent of the Kähler moduli, as is the case with anti-D3-branes, is inconsistent with data unless the matter and Higgs sectors are localized on D7 branes exclusively, or are confined to twisted sectors between D3-and D7-branes. We identify regions of parameter space for all possible D-brane configurations that remain consistent with Planck observations on the dark matter relic density and measurements of the CP-even Higgs mass at the LHC. Constraints arising from LHC searches at ?s =8 TeV and the LUX dark matter detection experiment are discussed. The discovery prospects for the remaining parameter space at dark matter direct-detection experiments are described, and signatures for detection of superpartners at the LHC with ?s =14 TeV are analyzed.

Kaufman, Bryan L.; Nelson, Brent D.

2014-04-01

202

On the worldsheet theory of the type IIA AdS(4) x CP(3) superstring

We perform a detailed study of the type IIA superstring in AdS(4)xCP(3). After introducing suitable bosonic light-cone and fermionic kappa worldsheet gauges we present the full SU(2|2)xU(1) covariant string Lagrangian. We then expand the theory in a strong coupling limit and derive the light-cone Hamiltonian up to quartic order in number of fields. To maintain a canonical Poisson structure we have to implement a shift of the fermionic coordinates with the result that the phase space Hamiltonian is rather involved. As a first application of our derivation we calculate energy shifts for string configurations in a closed fermionic subsector and successfully match these with a set of light-cone Bethe equations. We then turn to investigate the mismatch between the degrees of freedom of scattering states and oscillatory string modes. Since only light string modes appear as fundamental Bethe roots in the scattering theory, the physical role of the remaining 4f+4b massive oscillators is rather unclear. By continuing ...

Sundin, Per

2009-01-01

203

Constraining f(R) theories with Type Ia Supernovae and Gamma Ray Bursts

Fourth - order gravity theories have received much interest in recent years thanks to their ability to provide an accelerated cosmic expansion in a matter only universe. In these theories, the Lagrangian density of the gravitational field has the form R + f(R), and the explicit choice of the arbitrary function f(R) must meet the local tests of gravity and the constraints from the primordial abundance of the light elements. Two popular classes of f(R) models, which are expected to fulfill all the above requirements, have recently been proposed. However, neither of these models has ever been quantitatively tested against the available astrophysical data. Here, by combining Type Ia Supernovae and Gamma Ray Bursts, we investigate the ability of these models to reproduce the observed Hubble diagram over the redshift range (0, 7). We find that both models fit very well this dataset with the present day values of the matter density and deceleration parameters which agree with previous estimates. However, the strong ...

Cardone, Vincenzo F; Camera, Stefano

2009-01-01

204

Natural inflation with and without modulations in type IIB string theory

We propose a mechanism for the natural inflation with and without modulation in the framework of type IIB string theory on toroidal orientifold or orbifold. We explicitly construct the stabilization potential of complex structure, dilaton and K\\"ahler moduli, where one of the imaginary component of complex structure moduli becomes light which is identified as the inflaton. The inflaton potential is generated by the gaugino-condensation term which receives the one-loop threshold corrections determined by the field value of complex structure moduli and the axion decay constant of inflaton is enhanced by the inverse of one-loop factor. We also find the threshold corrections can also induce the modulations to the original scalar potential for the natural inflation. Depending on these modulations, we can predict several sizes of tensor-to-scalar ratio as well as the other cosmological observables reported by WMAP, Planck and/or BICEP2 collaborations.

Abe, Hiroyuki; Otsuka, Hajime

2014-01-01

205

Adaptation of learning resources based on the MBTI theory of psychological types

Directory of Open Access Journals (Sweden)

Full Text Available Today, the resources available on the web increases significantly. The motivation for the dissemination of knowledge and their acquisition by learners is central to learning. However, learners show differences between the ways of learning that suits them best. The objective of the work presented in this paper is to study how it is possible to integrate models from cognitive theories and ontologies for the adaptation of educational resources. The goal is to provide the system capabilities to conduct reasoning on descriptions obtained in order to automatically adapt the resources to a learner according to his preferences. We rely on the model MBTI (Myers-Briggs Type Indicator for the consideration of learning styles of learners as a criterion for adaptation.

Amel Behaz

2012-01-01

206

Conformally de Sitter space from anisotropic SD3-brane of type IIB string theory

We construct a four dimensional de Sitter space upto a conformal transformation by compactifying the anisotropic SD3-brane solution of type IIB string theory on a six dimensional product space of the form $H_5 \\times S^1$, where $H_5$ is a five dimensional hyperbolic space and $S^1$ is a circle. The radius of the hyperbolic space is chosen to be constant. The radius of the circle and the dilaton in four dimensions are time dependent and not constant in general. By different choices of parameters characterizing the SD3-brane solution either the dilaton or the radius of the circle can be made constant but not both. The form-field is also non-vanishing in general, but it can be made to vanish without affecting the solution. This construction might be useful for a better understanding of dS/CFT correspondence as well as for cosmology.

Roy, Shibaji

2014-01-01

207

New supersymmetric flux vacua of type II string theory and Generalized Complex Geometry

We study Minkowski supersymmetric flux vacua of type II string theory. Based on the work by M. Grana, R. Minasian, M. Petrini and A. Tomasiello, we briefly explain how to reformulate things in terms of Generalized Complex Geometry, which appears to be a natural framework for these compactifications. In particular, it provides a mathematical characterization of the internal manifold, and one is then able to find new solutions, which cannot be constructed as usual via T-dualities from a warped T^6 solution. Furthermore, we discuss how, thanks to a specific change of variables, one can ease the resolution of the orientifold projection constraints pointed out by P. Koerber and D. Tsimpis. One is then able to find new solutions with intermediate SU(2) structure.

Andriot, David

2009-01-01

208

New supersymmetric flux vacua of type II string theory and generalized complex geometry

International Nuclear Information System (INIS)

We study Minkowski supersymmetric flux vacua of type II string theory. Based on the work by M. Grana, R. Minasian, M. Petrini and A. Tomasiello, we briefly explain how to reformulate things in terms of Generalized Complex Geometry, which appears to be a natural framework for these compactifications. In particular, it provides a mathematical characterization of the internal manifold, and one is then able to find new solutions, which cannot be constructed as usual via T-dualities from a warped T6 solution. Furthermore, we discuss how, thanks to a specific change of variables, one can ease the resolution of the orientifold projection constraints pointed out by P. Koerber and D. Tsimpis. One is then able to find new solutions with intermediate SU(2) structure. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

209

Cosmic String Solution in a Born-Infeld Type Theory of Gravity

In this work we derive an exact solution for the exterior metric of a local cosmic string in an effective theory of gravity, the so-called NDL theory, which is inspired in the Born-Infeld theory. The solution is given by a family of parameters which presents quite different features from that of the General Relativity theory. The differences come from the specific choice of the gravitation Lagrangian which is based on a spin-1 construction of the gravitation theory.

da Rocha, W J; Guimarães, M E X

2009-01-01

210

LRS Bianchi type -V cosmology with heat flow in scalar-tensor theory

International Nuclear Information System (INIS)

In this paper we present a spatially homogeneous locally rotationally symmetric (LRS) Bianchi type -V perfect fluid model with heat conduction in scalar tensor theory proposed by Saez and Ballester. The field equations are solved with and without heat conduction by using a law of variation for the mean Hubble parameter, which is related to the average scale factor of metric and yields a constant value for the deceleration parameter. The law of variation for the mean Hubble parameter generates two types of cosmologies one is of power -law form and second the exponential form. Using these two forms singular and non -singular solutions are obtained with and without heat conduction. We observe that a constant value of the deceleration parameter is reasonable a description of the different phases of the universe. We arrive to the conclusion that the universe decelerates for positive value of deceleration parameter where as it accelerates for negative one. The physical constraints on the solutions of the field equations, and, in particular, the thermodynamical laws and energy conditions that govern such solutions are discussed in some detail.The behavior of the observationally important parameters like expansion scalar, anisotropy parameter and shear scalar is considered in detail. (author)

211

LRS Bianchi type -V cosmology with heat flow in scalar-tensor theory

Energy Technology Data Exchange (ETDEWEB)

In this paper we present a spatially homogeneous locally rotationally symmetric (LRS) Bianchi type -V perfect fluid model with heat conduction in scalar tensor theory proposed by Saez and Ballester. The field equations are solved with and without heat conduction by using a law of variation for the mean Hubble parameter, which is related to the average scale factor of metric and yields a constant value for the deceleration parameter. The law of variation for the mean Hubble parameter generates two types of cosmologies one is of power -law form and second the exponential form. Using these two forms singular and non -singular solutions are obtained with and without heat conduction. We observe that a constant value of the deceleration parameter is reasonable a description of the different phases of the universe. We arrive to the conclusion that the universe decelerates for positive value of deceleration parameter where as it accelerates for negative one. The physical constraints on the solutions of the field equations, and, in particular, the thermodynamical laws and energy conditions that govern such solutions are discussed in some detail.The behavior of the observationally important parameters like expansion scalar, anisotropy parameter and shear scalar is considered in detail. (author)

Singh, C.P. [Delhi College of Engineering, Delhi (India). Dept. of Applied Mathematics], e-mail: cpsphd@rediffmail.com

2009-12-15

212

LRS Bianchi type -V cosmology with heat flow in scalar: tensor theory

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english In this paper we present a spatially homogeneous locally rotationally symmetric (LRS) Bianchi type -V perfect fluid model with heat conduction in scalar tensor theory proposed by Saez and Ballester. The field equations are solved with and without heat conduction by using a law of variation for the m [...] ean Hubble parameter, which is related to the average scale factor of metric and yields a constant value for the deceleration parameter. The law of variation for the mean Hubble parameter generates two types of cosmologies one is of power -law form and second the exponential form. Using these two forms singular and non -singular solutions are obtained with and without heat conduction. We observe that a constant value of the deceleration parameter is reasonable a description of the different phases of the universe. We arrive to the conclusion that the universe decelerates for positive value of deceleration parameter where as it accelerates for negative one. The physical constraints on the solutions of the field equations, and, in particular, the thermodynamical laws and energy conditions that govern such solutions are discussed in some detail.The behavior of the observationally important parameters like expansion scalar, anisotropy parameter and shear scalar is considered in detail.

C.P., Singh.

2009-12-01

213

LRS Bianchi type -V cosmology with heat flow in scalar: tensor theory

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english In this paper we present a spatially homogeneous locally rotationally symmetric (LRS) Bianchi type -V perfect fluid model with heat conduction in scalar tensor theory proposed by Saez and Ballester. The field equations are solved with and without heat conduction by using a law of variation for the m [...] ean Hubble parameter, which is related to the average scale factor of metric and yields a constant value for the deceleration parameter. The law of variation for the mean Hubble parameter generates two types of cosmologies one is of power -law form and second the exponential form. Using these two forms singular and non -singular solutions are obtained with and without heat conduction. We observe that a constant value of the deceleration parameter is reasonable a description of the different phases of the universe. We arrive to the conclusion that the universe decelerates for positive value of deceleration parameter where as it accelerates for negative one. The physical constraints on the solutions of the field equations, and, in particular, the thermodynamical laws and energy conditions that govern such solutions are discussed in some detail.The behavior of the observationally important parameters like expansion scalar, anisotropy parameter and shear scalar is considered in detail.

C.P., Singh.

214

International Nuclear Information System (INIS)

Many inner ear disorders, including Meniere's disease, are believed to be based on endolymphatic hydrops. We evaluated a newly proposed method for semi-quantification of endolymphatic size in patients with suspected endolymphatic hydrops that uses 2 kinds of processed magnetic resonance (MR) images. Twenty-four consecutive patients underwent heavily T2-weighted (hT2W) MR cisternography (MRC), hT2W 3-dimensional (3D) fluid-attenuated inversion recovery (FLAIR) with inversion time of 2250 ms (positive perilymph image, PPI), and hT2W-3D-IR with inversion time of 2050 ms (positive endolymph image, PEI) 4 hours after intravenous administration of single-dose gadolinium-based contrast material (IV-SD-GBCM). Two images were generated using 2 new methods to process PPI, PEI, and MRC. Three radiologists contoured the cochlea and vestibule on MRC, copied regions of interest (ROIs) onto the 2 kinds of generated images, and semi-quantitatively measured the size of the endolymph for the cochlea and vestibule by setting a threshold pixel value. Each observer noted a strong linear correlation between endolymphatic size of both the cochlea and vestibule of the 2 kinds of generated images. The Pearson correlation coefficients (r) were 0.783, 0.734, and 0.800 in the cochlea and 0.924, 0.930, and 0.933 in the vestibule (P<0.001, for all). In both the cochlea and vestibule, repeated-measures analysis of variance showed no statistically significant difference between observers. Use of the 2 kinds of generated images generated from MR images obtained 4 hours after IV-SD-GBCM might enable semi-quantification of endolymphatic size with little observer dependency. (author)

215

A Novel Framework for Quantification of Supply Chain Risks

Digital Repository Infrastructure Vision for European Research (DRIVER)

Supply chain risk management is an active area of research and there is a research gap of exploring established risk quantification techniques in other fields for application in the context of supply chain management. We have developed a novel framework for quantification of supply chain risks that integrates two techniques of Bayesian belief network and Game theory. Bayesian belief network can capture interdependency between risk factors and Game theory can assess risks associated with confl...

Qazi, Abroon; Quigley, John; Dickson, Alex

2014-01-01

216

Metaontology and the problem of quantification

Digital Repository Infrastructure Vision for European Research (DRIVER)

This text is concerned with the latest philosophical discipline - metaontology - which main objective is to examine traditional metaphysics and ontological sentences which it includes, as well as with its main theories pluralism, realism and skepticism. While first two of these theories try to provide more or less acceptable arguments in their favor, and show that quantification is justified, it will be shown that they make crucial mistake by neglecting problem of ontological commitment, whic...

Man?i? Željko

2009-01-01

217

Theory of de Haas-van Alphen Effect in Type-II Superconductor

Theory of quasiparticle spectra and the de Haas-van Alphen (dHvA) oscillation in type-II superconductors are developed based on the Bogoliubov-de Gennes equations for vortex-lattice states. As the pair potential grows through the superconducting transition, each degenerate Landau level in the normal state splits into quasiparticle bands in the magnetic Brillouin zone. This brings Landau-level broadening, which in turn leads to the extra dHvA oscillation damping in the vortex state. We perform extensive numerical calculations for three-dimensional systems with various gap structures. It is thereby shown that (i) this Landau-level broadening is directly connected with the average gap at H=0 along each Fermi-surface orbit perpendicular to the field H; (ii) the extra dHvA oscillation attenuation is caused by the broadening around each extremal orbit. These results imply that the dHvA experiment can be a unique probe to detect band- and/or angle-dependent gap amplitudes. We derive an analytic expression for the ex...

KIta, T

2002-01-01

218

From Peierls brackets to a generalized Moyal bracket for type-I gauge theories

In the space-of-histories approach to gauge fields and their quantization, the Maxwell, Yang--Mills and gravitational field are well known to share the property of being type-I theories, i.e. Lie brackets of the vector fields which leave the action functional invariant are linear combinations of such vector fields, with coefficients of linear combination given by structure constants. The corresponding gauge-field operator in the functional integral for the in-out amplitude is an invertible second-order differential operator. For such an operator, we consider advanced and retarded Green functions giving rise to a Peierls bracket among group-invariant functionals. Our Peierls bracket is a Poisson bracket on the space of all group-invariant functionals in two cases only: either the gauge-fixing is arbitrary but the gauge fields lie on the dynamical sub-space; or the gauge-fixing is a linear functional of gauge fields, which are generic points of the space of histories. In both cases, the resulting Peierls bracke...

Esposito, G; Esposito, Giampiero; Stornaiolo, Cosimo

2006-01-01

219

Chern class identities from tadpole matching in type IIB and F-theory

In light of Sen's weak coupling limit of F-theory as a type IIB orientifold, the compatibility of the tadpole conditions leads to a non-trivial identity relating the Euler characteristics of an elliptically fibered Calabi-Yau fourfold and of certain related surfaces. We present the physical argument leading to the identity, and a mathematical derivation of a Chern class identity which confirms it, after taking into account singularities of the relevant loci. This identity of Chern classes holds in arbitrary dimension, and for varieties that are not necessarily Calabi-Yau. Singularities are essential in both the physics and the mathematics arguments: the tadpole relation may be interpreted as an identity involving stringy invariants of a singular hypersurface, and corrections for the presence of pinch-points. The mathematical discussion is streamlined by the use of Chern-Schwartz-MacPherson classes of singular varieties. We also show how the main identity may be obtained by applying `Verdier specialization' to...

Aluffi, Paolo

2009-01-01

220

A polynomial transform is the multiplication of an input vector $x\\in\\C^n$ by a matrix $\\PT_{b,\\alpha}\\in\\C^{n\\times n},$ whose $(k,\\ell)$-th element is defined as $p_\\ell(\\alpha_k)$ for polynomials $p_\\ell(x)\\in\\C[x]$ from a list $b=\\{p_0(x),\\dots,p_{n-1}(x)\\}$ and sample points $\\alpha_k\\in\\C$ from a list $\\alpha=\\{\\alpha_0,\\dots,\\alpha_{n-1}\\}$. Such transforms find applications in the areas of signal processing, data compression, and function interpolation. Important examples include the discrete Fourier and cosine transforms. In this paper we introduce a novel technique to derive fast algorithms for polynomial transforms. The technique uses the relationship between polynomial transforms and the representation theory of polynomial algebras. Specifically, we derive algorithms by decomposing the regular modules of these algebras as a stepwise induction. As an application, we derive novel $O(n\\log{n})$ general-radix algorithms for the discrete Fourier transform and the discrete cosine transform of type 4.

Sandryhaila, Aliaksei; Pueschel, Markus

2010-01-01

221

Higher Dimensional LRS Bianchi Type-I Domain Walls in a Scalar-Tensor Theory of Gravitation

An exact higher dimensional LRS Bianchi type-I cosmological model is obtained in presence of thick domain walls in a scalar tensor theory of gravitation proposed by Saez and Ballester (Phys. Lett. A113:467, 1985). Some physical and kinematical properties of the models are also discussed.

Katore, S. D.; Adhav, K. S.; Shaikh, A. Y.; Sarkate, N. K.

2010-10-01

222

A spatially homogeneous and anisotropic Bianchi type-II cosmological model is obtained in a scalar tensor theory of gravitation proposed by Saez and Ballester (Phys. Lett. A 130:467, 1986) when the source for energy momentum tensor is a bulk viscous fluid containing one-dimensional cosmic strings. Some physical and kinematical properties of the model are also discussed.

Naidu, R. L.; Satyanarayana, B.; Reddy, D. R. K.

2012-04-01

223

De-Sitter Type of Cosmological Model in n-Dimensional Space-Time-Mass (STM) Theory of Gravitation

Exact solution are obtained for a homogeneous spacially isotropic cosmological model in a matter free space with or without cosmological consant for a n-dimensional Kaluza-Klein type of metric in the rest mass varying theory of gravity proposed by Wesson[1983]. The behavior of the model is discussed.

Khadekar, G S; Patki, Vrishali

2002-01-01

224

Metaontology and the problem of quantification

Directory of Open Access Journals (Sweden)

Full Text Available This text is concerned with the latest philosophical discipline - metaontology - which main objective is to examine traditional metaphysics and ontological sentences which it includes, as well as with its main theories pluralism, realism and skepticism. While first two of these theories try to provide more or less acceptable arguments in their favor, and show that quantification is justified, it will be shown that they make crucial mistake by neglecting problem of ontological commitment, which is, basically, main source of all metaphysical issues. I shall try to put forward advantages of skepticism over these rival theories, and why one should embrace it in metaontology.

Man?i? Željko

2009-01-01

225

International Nuclear Information System (INIS)

I introduce a critical-state theory incorporating both flux cutting and flux transport to calculate the magnetic-field and current-density distributions inside a type-II superconducting cylinder at its critical current in a longitudinal applied magnetic field. The theory is an extension of the elliptic critical-state model introduced by Romero-Salazar and Perez-Rodriguez. The vortex dynamics depend in detail on two nonlinear effective resistivities for flux cutting (?(parallel)) and flux flow (?(perpendicular)), and their ratio r = ?(parallel)/?(perpendicular). When r c(?) that makes the vortex arc unstable.

226

Directory of Open Access Journals (Sweden)

Full Text Available Trans-esophageal echocardiography (TEE is routinely used in valvular surgery in most institutions. The popularity of TEE stems from the fact that it can supplement or confirm information gained from other methods of evaluation or make completely independant diagnoses. Quantitative and qualitative assessment permits informed decisions regarding surgical intervention, type of intervention, correction of inadequate surgical repair and re-operation for complications. This review summarizes the various methods for quantification of aortic regurgitation and stenosis on TEE. The application of Doppler echo (pulsed wave, continuous wave and color with two-dimensional echo allows the complete evaluation of AV lesions.

Mehta Yatin

2009-01-01

227

Advances in type-2 fuzzy sets and systems theory and applications

This book explores recent developments in the theoretical foundations and novel applications of general and interval type-2 fuzzy sets and systems, including: algebraic properties of type-2 fuzzy sets, geometric-based definition of type-2 fuzzy set operators, generalizations of the continuous KM algorithm, adaptiveness and novelty of interval type-2 fuzzy logic controllers, relations between conceptual spaces and type-2 fuzzy sets, type-2 fuzzy logic systems versus perceptual computers; modeling human perception of real world concepts with type-2 fuzzy sets, different methods for generating membership functions of interval and general type-2 fuzzy sets, and applications of interval type-2 fuzzy sets to control, machine tooling, image processing and diet. The applications demonstrate the appropriateness of using type-2 fuzzy sets and systems in real world problems that are characterized by different degrees of uncertainty.

Mendel, Jerry; Tahayori, Hooman

2013-01-01

228

Generalized canonical formalism and S matrix of theories with constraints of general type

International Nuclear Information System (INIS)

The method of canonical quantization of systems with constraints of the first and second class of an arbitrary rank is discussed. The effectiveness of the method is demonstrated using the Yang-Mills fields and gravitational fields as examples. A correct expression for the S matrix of theories quadratic in momenta within the frames of canonical gauges including ghost fields is derived. General quantization is performed and the S matrix in a configurational space for relativistic membrane theories, being a generalization of the string theories to the case of extended spatial realization, is obtained. It is shown that the membrane theory in the space of n+1 measurements is a system with constraints of the n rank

229

Fitting the luminosity data from type Ia supernovae in the frame of the Cosmic Defect theory

The Cosmic Defect (CD) theory is reviewed and used to fit the data for the accelerated expansion of the universe, obtained from the apparent luminosity of 192 SnIa's. The fit from CD is compared with the one obtained by means of $\\Lambda $CDM. The results from both theories are in good agreement and the fits are satisfactory. The correspondence between both approaches is discussed and interpreted.

Tartaglia, A; Cardone, V; Radicella, N

2008-01-01

230

We construct an Eliahou-Kervaire-like minimal free resolution of the alternative polarization $b-pol(I)$ of a Borel fixed ideal $I$. It yields new descriptions of the minimal free resolutions of $I$ itself and $I^sq$, where $(-)^sq$ is the squarefree operation in the shifting theory. These resolutions are cellular, and the (common) supporting cell complex is given by discrete Morse theory. If $I$ is generated in one degree, our description is equivalent to that of Nagel and Reiner.

Okazaki, Ryota

2011-01-01

231

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Regular physical activity is considered a cornerstone for managing type 2 diabetes. However, in Canada, most individuals with type 2 diabetes do not meet national physical activity recommendations. When designing a theory-based intervention, one should first determine the key determinants of physical activity for this population. Unfortunately, there is a lack of information on this aspect among adults with type 2 diabetes. The purpose of this cross-sectional study is to fill this gap using an extended version of Ajzen's Theory of Planned Behavior (TPB as reference. Methods A total of 501 individuals with type 2 diabetes residing in the Province of Quebec (Canada completed the study. Questionnaires were sent and returned by mail. Results Multiple hierarchical regression analyses indicated that TPB variables explained 60% of the variance in intention. The addition of other psychosocial variables in the model added 7% of the explained variance. The final model included perceived behavioral control (? = .38, p Conclusion The findings suggest that interventions aimed at individuals with type 2 diabetes should ensure that people have the necessary resources to overcome potential obstacles to behavioral performance. Interventions should also favor the development of feelings of personal responsibility to exercise and promote the advantages of exercising for individuals with type 2 diabetes.

Godin Gaston

2009-06-01

232

International Nuclear Information System (INIS)

We discuss Bianchi type-VII0 cosmology with a Dirac field in the Einstein—Cartan (E-C) theory and obtain the equations of the Dirac and gravitational fields in the E-C theory. A Bianchi type-VII0 inflationary solution is found. When (3)/16S2 - ?2 > 0, the Universe may avoid singularity. (geophysics, astronomy, and astrophysics)

233

Bianchi type-I model with cosmological constant in a generalized scalar-tensor theory of gravitation

International Nuclear Information System (INIS)

Bianchi type-I cosmological models are discussed in the Bergmann-Wagoner-Nordtvedt scalar-tensor theory where both the so-called cosmological constant ? and the coupling parameter ? are taken to be functions of the scalar field phi. Exact solutions are obtained in Dicke's revised units assuming a very simple relationship between ? and phi. The properties of the models are discussed in special cases

234

Holographic-Type Gravitation via Non-Differentiability in Weyl-Dirac Theory

Directory of Open Access Journals (Sweden)

Full Text Available In the Weyl-Dirac non-relativistic hydrodynamics approach, the non-linear interaction between sub-quantum level and particle gives non-differentiable properties to the space. Therefore, the movement trajectories are fractal curves, the dynamics are described by a complex speed field and the equation of motion is identified with the geodesics of a fractal space which corresponds to a Schrodinger non-linear equation. The real part of the complex speed field assures, through a quantification condition, the compatibility between the Weyl-Dirac non-elativistic hydrodynamic model and the wave mechanics. The mean value of the fractal speed potential, identifies with the Shanon informational energy, specifies, by a maximization principle, that the sub-quantum level “stores” and “transfers” the informational energy in the form of force. The wave-particle duality is achieved by means of cnoidal oscillations modes of the state density, the dominance of one of the characters, wave or particle, being put into correspondence with two flow regimes (non-quasi-autonomous and quasi-autonomous of the Weyl-Dirac fluid. All these show a direct connection between the fractal structure of space and holographic principle.

Mihai Pricop

2013-08-01

235

To the full order in fermions, we construct D=10 type II supersymmetric double field theory. We spell the precise N=2 supersymmetry transformation rules as for 32 supercharges. In terms of stringy differential geometry we have previously developed beyond Riemann, our action treats R-R sector democratically and unifies type IIA and IIB supergravities in a manifestly covariant fashion, with respect to O(10,10) T-duality and a pair of local Lorentz groups, Spin(1,9) \\times Spin(9,1), in addition to the usual general covariance of the supergravities.

Jeon, Imtak; Park, Jeong-Hyuck; Suh, Yoonji

2013-01-01

236

We prove local and global versions of Borg-Marchenko-type uniqueness theorems for half-lattice and full-lattice CMV operators (CMV for Cantero, Moral, and Velazquez) with matrix-valued Verblunsky coefficients. While our half-lattice results are formulated in terms of matrix-valued Weyl-Titchmarsh functions, our full-lattice results involve the diagonal and main off-diagonal Green's matrices. We also develop the basics of Weyl-Titchmarsh theory for CMV operators with matrix-valued Verblunsky coefficients as this is of independent interest and an essential ingredient in proving the corresponding Borg-Marchenko-type uniqueness theorems.

Clark, Stephen; Zinchenko, Maxim

2010-01-01

237

DEFF Research Database (Denmark)

AIMS/HYPOTHESIS: We compared four methods to assess their accuracy in measuring insulin secretion during an intravenous glucose tolerance test in patients with Type II (non-insulin-dependent) diabetes mellitus and with varying beta-cell function and matched control subjects. METHODS: Eight control subjects and eight Type II diabetic patients underwent an intravenous glucose tolerance test with tolbutamide and an intravenous bolus injection of C-peptide to assess C-peptide kinetics. Insulin secretion rates were determined by the Eaton deconvolution (reference method), the Insulin SECretion method (ISEC) based on population kinetic parameters as well as one-compartment and two-compartment versions of the combined model of insulin and C-peptide kinetics. To allow a comparison of the accuracy of the four methods, fasting rates and amounts of insulin secreted during the first phase (0-10 min) and the second phase (10-180 min) were calculated. RESULTS: All secretion responses from the ISEC method were strongly correlated to those obtained by the Eaton deconvolution method (r = 0.83-0.92). The one-compartment combined model, however, showed a high correlation to the reference method only for the first-phase insulin response (r = 0.78). The two-compartment combined model failed to provide reliable estimates of insulin secretion in three of the control subjects and in two patients with Type II diabetes. The four methods were accurate with respect to mean basal and first-phase secretion response. The one-compartment and two-compartment combined models were less accurate in measuring the second-phase response. CONCLUSION/INTERPRETATION: The ISEC method can be applied to normal, obese or Type II diabetic patients. In patients with deviating kinetics of C-peptide the Eaton deconvolution method is the method of choice while the one-compartment combined model is suitable for measuring only the first-phase insulin secretion.

Kjems, L L; VØlund, A

2001-01-01

238

Toward a Two-Factor Theory of One Type of Mathematics Disabilities.

This article proposes a two-factor theory of mathematics disabilities based on the premise that weak cognitive representations lead to poorer retrieval of information from long term memory. Comparison of children with math disabilities alone (MD) and those with both math and reading disabilities (MD/RD) suggests that weak phonological processing…

Robinson, Carol S.; Menchetti, Bruce M.; Torgesen, Joseph K.

2002-01-01

239

On the effective potential of the Dp - anti-Dp system in type II theories.

Digital Repository Infrastructure Vision for European Research (DRIVER)

We compute the effective potential of a system composed by a Dp brane and a separated anti-Dp brane at tree level in string theory. We show explicitly that the tachyon condenses and that the scalars which describe transverse fluctuations acquire a VEV proportional to the distance.

Pesando, Igor

1999-01-01

240

We study the Cauchy problem for an $p$-Laplacian type of evolution system ${\\mathbf H}_{t}+\\g [ | \\g {\\mathbf H}|^{p-2} \\g {\\mathbf H}|]={\\mathbf F}$. This system governs the evolution of a magnetic field ${\\bf H}$, where the current displacement is neglected and the electrical resistivity is assumed to be some power of the current density. The existence, uniqueness and regularity of solutions to the system are established. Furthermore, it is shown that the limit solution as the power $p\\rightarrow \\infty$ solves the problem of Bean's model in the type-II superconductivity theory. The result provides us information about how the superconductor material under the external force to become the normal conductor and vice visa. It also provides an effective method to find numerical solutions to Bean's model.

Yin, H M

1998-01-01

241

A proficiency test for the analysis of pesticide residues in brown rice was carried out to support upgrading in analytical skills of participant laboratories. Brown rice containing three target pesticides (etofenprox, fenitrothion, and isoprothiolane) was used as the test samples. The test samples were distributed to the 57 participants and analyzed by appropriate analytical methods chosen by each participant. It was shown that there was no significant difference among the reported values obtained by different types of analytical method. The analytical results obtained by National Metrology Institute of Japan (NMIJ) were 3 % to 10 % greater than those obtained by participants. The results reported by the participant were evaluated by using two types of z-scores, that is, one was the score based on the consensus values calculated from the analytical results of participants, and the other one was the score based on the reference values obtained by NMIJ with high reliability. Acceptable z-scores based on the consensus values and NMIJ reference values were achieved by 87 % to 89 % and 79 % to 94 % of the participants, respectively. PMID:25258285

Otake, Takamitsu; Yarita, Takashi; Aoyagi, Yoshie; Numata, Masahiko; Takatsu, Akiko

2014-11-01

242

International Nuclear Information System (INIS)

Open and closed boson theories are discussed in a classical framework, highlighting the physical interpretation of conformal symmetry and the Virasoro (1970) algebra. The quantification of bosonic strings is done within the old covariant operational formalism. This method is much less elegant and powerful than the BRST quantification, but it quickly reveals the physical content of quantum theory. Generalization to theories with fermionic degrees of freedom is introduced: the Neveu-Schartz (1971) and Ramond (1971) models, their reduced supersymmetry (two dimensions) and the Gliozzi, Scherk and Olive (1977) projection which leads to a supersymmetry theory in the usual meaning of the term

243

The average Pb/U ratio of the Shea Creek unconformity-type uranium deposit has been estimated at 0.071±0.015. The calculation was performed on a volume enclosing the orebody to take into account the possible radiogenic lead migration within the ore zone. Despite this precaution, this ratio is significantly lower than the expected ratio (0.211) assuming a main U deposition around 1315 Ma, as suggested by previous U?Pb isotopic dating. Although part of the radiogenic lead can be trapped as galena within the orebody, about 60% of Pb have migrated more than 700 m away from the orebody, preferentially along the unconformity. To cite this article: P. Kister et al., C. R. Geoscience 336 (2004).

Kister, Philippe; Cuney, Michel; Golubev, Viacheslav N.; Royer, Jean-Jacques; Le Carlier De Veslud, Christian; Rippert, Jean-Claude

2004-03-01

244

KK-monopoles and G-structures in M-theory/type IIA reductions

We argue that M-theory/massive IIA backgrounds including KK-monopoles are suitably described in the language of G-structures and their intrinsic torsion. To this end, we study classes of minimal supergravity models that admit an interpretation as twisted reductions in which the twist parameters are not restricted to satisfy the Jacobi constraints $\\omega\\, \\omega=0$ required by an ordinary Scherk-Schwarz reduction. We first derive the correspondence between four-dimensional data and torsion classes of the internal space and, then, check the one-to-one correspondence between higher-dimensional and four-dimensional equations of motion. Remarkably, the whole construction holds regardless of the Jacobi constraints, thus shedding light upon the string/M-theory interpretation of (smeared) KK-monopoles.

Danielsson, Ulf; Guarino, Adolfo

2014-01-01

245

We describe in this talk three methods of constructing different links with the same Jones type invariant. All three can be thought as generalizations of mutation. The first combines the satellite construction with mutation. The second uses the notion of rotant, taken from the graph theory, the third, invented by Jones, transplants into knot theory the idea of the Yang-Baxter equation with the spectral parameter (idea employed by Baxter in the theory of solvable models in statistical mechanics). We extend the Jones result and relate it to Traczyk's work on rotors of links. We also show further applications of the Jones idea, e.g. to 3-string links in the solid torus. We stress the fact that ideas coming from various areas of mathematics (and theoretical physics) has been fruitfully used in knot theory, and vice versa. (This is the detailed version of the talk given at the Banach Center Colloquium, Warsaw, Poland, March 24, 1994: ``W poszukiwaniu nietrywialnego wezla z trywialnym wielomianem Jonesa: grafy i me...

Przytycki, J H

1995-01-01

246

Adaptation of learning resources based on the MBTI theory of psychological types

Digital Repository Infrastructure Vision for European Research (DRIVER)

Today, the resources available on the web increases significantly. The motivation for the dissemination of knowledge and their acquisition by learners is central to learning. However, learners show differences between the ways of learning that suits them best. The objective of the work presented in this paper is to study how it is possible to integrate models from cognitive theories and ontologies for the adaptation of educational resources. The goal is to provide the system capabilities to c...

Amel Behaz; Mahieddine Djoudi

2012-01-01

247

International Nuclear Information System (INIS)

A method is proposed that makes it possible to determine whether a timelike singularity corresponds to a point, linear, or other type of gravitational field source. It is shown that in the general theory of relativity it is also possible to have sources of a quite different type with no analogs in a space of finite curvature. An analysis is made of some well-known solutions containing timelike singularities whose type varies depending on the signs of the functions that occur in the solutions. The form of the solution near simple linear sources [W. Israel, Phys. Rev. D15, 935 (1977)] and generalized anisotropic solutions [S. L. Parnovsky, Physica (Utrecht) 104A, 210 (1980); E. M. Lifshitz and I. M. Khalatnikov, Sov. Phys. Usp. 6, 359 (1963)] is determined more accurately; the space-time described by the ? metric (3) is completely investigated; and the form of the metric near the ends and singular points of linear Weyl singularities is found

248

Existing, competing theories for coronal and interplanetary type III solar radio bursts appeal to one or more of modulational instability, electrostatic (ES) decay processes, or stochastic growth physics to preserve the electron beam, limit the levels of Langmuir-like waves driven by the beam, and produce wave spectra capable of coupling nonlinearly to generate the observed radio emission. Theoretical constraints exist on the wavenumbers and relative sizes of the wave bandwidth and nonlinear growth rate for which Langmuir waves are subject to modulational instability and the parametric and random phase versions of ES decay. A constraint also exists on whether stochastic growth theory (SGT) is appropriate. These constraints are evaluated here using the beam, plasma, and wave properties (1) observed in specific interplanetary type III sources, (2) predicted nominally for the corona, and (3) predicted at heliocentric distances greater than a few solar radii by power-law models based on interplanetary observations. It is found that the Langmuir waves driven directly by the beam have wavenumbers that are almost always too large for modulational instability but are appropriate to ES decay. Even for waves scattered to lower wavenumbers (by ES decay, for instance), the wave bandwidths are predicted to be too large and the nonlinear growth rates too small for modulational instability to occur for the specific interplanetary events studied or the great majority of Langmuir wave packets in type III sources at arbitrary heliocentric distances. Possible exceptions are for very rare, unusually intense, narrowband wave packets, predominantly close to the Sun, and for the front portion of very fast beams traveling through unusually dilute, cold solar wind plasmas. Similar arguments demonstrate that the ES decay should proceed almost always as a random phase process rather than a parametric process, with similar exceptions. These results imply that it is extremely rare for modulational instability or parametric decay to proceed in type III sources at any heliocentric distance: theories for type III bursts based on modulational instability or parametric decay are therefore not viable in general. In contrast, the constraint on SGT can be satisfied and random phase ES decay can proceed at all heliocentric distances under almost all circumstances. (The contrary circumstances involve unusually slow, broad beams moving through unusually hot regions of the Corona.) The analyses presented here strongly justify extending the existing SGT-based model for interplanetary type III bursts (which includes SGT physics, random phase ES decay, and specific electromagnetic emission mechanisms) into a general theory for type III bursts from the corona to beyond 1 AU. This extended theory enjoys strong theoretical support, explains the characteristics of specific interplanetary type III bursts very well, and can account for the detailed dynamic spectra of type III bursts from the lower corona and solar wind.

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

1998-01-01

249

An optimized method of ultrasound-assisted extraction followed by ultra-high-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UAE-UHPLC-TQ/MS(2)) was proposed for the simultaneous extraction and determination of 26 characteristic components covering four structure types (flavonoids, terpene lactones, ginkgolic acids and phenylpropanols) in ginkgo seeds (GSs). The UAE parameters (ultrasound power, time and solvent-to-material ratio) were optimized using a response surface methodology. This is the first report of the simultaneous analysis of 26 compounds in Ginkgo biloba using UHPLC-TQ/MS(2); this analysis afforded good linearity, precision, repeatability and accuracy. UAE-UHPLC-TQ/MS(2) was successfully applied to ginkgo seed samples, and the analysis showed that GSs are rich in terpene lactones and could be selected as a healthy food resource. The results suggest that UAE-UHPLC-TQ/MS(2) might be able to be utilized as a tool for the quality assessment of samples from GSs or other related products using flavonoids, terpene lactones, ginkgolic acids and phenylpropanols as markers. PMID:24731329

Zhou, Guisheng; Yao, Xin; Tang, Yuping; Qian, Dawei; Su, Shulan; Zhang, Li; Jin, Chun; Qin, Yong; Duan, Jin-ao

2014-09-01

250

The isotropic theory of viscoplasticity based on overstress does not use a yield surface or a loading and unloading criterion. The inelastic strain rate depends on overstress, the difference between the stress and the equilibrium stress, and is assumed to be rate dependent. Special attention is paid to the modeling of elastic regions. For the modeling of cyclic hardening, such as observed in annealed Type 304 stainless steel, and additional growth law for a scalar quantity which represents the rate independent asymptotic value of the equilibrium stress is added. It is made to increase with inelastic deformation using a new scalar measure which differentiates between nonproportional and proportional loading. The theory is applied to correlate uniaxial data under two step amplitude loading including the effect of further hardening at the high amplitude and proportional and nonproportional cyclic loadings. Results are compared with corresponding experiments.

Yao, David; Krempl, Erhard

1988-01-01

251

Separation and storage of plasma within 2 h of phlebotomy is required for the VACUTAINER PPT Plasma Preparation Tube (PPT) versus 4 h for the predecessor VACUTAINER EDTA tube for human immunodeficiency virus type 1 (HIV-1) viral load (HIVL) testing by the VERSANT HIV-1 RNA 3.0 assay (branched DNA). The 2-h limit for PPT imposes time constraints for handling and transporting to the testing laboratory. This study compares HIVL reproducibility from matched blood in EDTA tubes and PPTs and between PPT pairs following processing within 4 h of phlebotomy, stability of plasma HIV-1 RNA at 24- and 72-h room temperature storage in the tube, and comparative labor and supply requirements. Blood from 159 patients was collected in paired tubes (EDTA/PPT or PPT/PPT): 86 paired EDTA tubes and PPTs were processed 4 h following phlebotomy and their HIVLs were compared, 42 paired PPT/PPT pairs were analyzed for intertube HIVL reproducibility, and 31 PPT/PPT pairs were analyzed for HIV-1 RNA stability by HIVL. Labor and supply requirements were compared between PPT and EDTA tubes. PPTs produce results equivalent to standard EDTA tube results when processed 4 h after phlebotomy. PPT intertube analyte results are reproducible. An average decrease of 13% and 37% in HIVL was observed in PPT plasma after 24 and 72 h of room temperature storage, respectively; thus, plasma can be stored at room temperature up to 24 h in the original tube. PPTs offer labor and supply savings over EDTA tubes. PMID:16081908

Elbeik, Tarek; Nassos, Patricia; Kipnis, Patricia; Haller, Barbara; Ng, Valerie L

2005-08-01

252

DEFF Research Database (Denmark)

As a part of a prospective cohort study in four herds, a nested case control study was carried out. Five slow growing pigs (cases) and five fast growing pigs (controls) out of 60 pigs were selected for euthanasia and laboratory examination at the end of the study in each herd. A total of 238 pigs, all approximately 12 weeks old, were included in the study during the first week in the grower–finisher barn. In each herd, approximately 60 pigs from four pens were individually ear tagged. The pigs were weighed at the beginning of the study and at the end of the 6–8 weeks observation period. Clinical data, blood and faecal samples were serially collected from the 60 selected piglets every second week in the observation period. In the killed pigs serum was examined for antibodies against Lawsonia intracellularis (LI) and procine circovirus type 2 (PCV2) and in addition PCV2 viral DNA content was quantified. In faeces the quantity of LI cells/g faeces and number of PCV2 copies/g faeces was measured by qPCR. The objective of the study was to examine if growth rate in grower-finishing pig is associated with the detection of LI and PCV2 infection or clinical data. This study has shown that diarrhoea is a significant risk factor for low growth rate and that one log10 unit increase in LI load increases the odds ratio for a pig to have a low growth rate by 2.0 times. Gross lesions in the small intestine and LI load > log10 6/g were significant risk factors for low growth. No association between PCV2 virus and low growth was found.

Johansen, Markku; Nielsen, MaiBritt

2013-01-01

253

Weyl Group Multiple Dirichlet Series Type A Combinatorial Theory (AM-175)

Weyl group multiple Dirichlet series are generalizations of the Riemann zeta function. Like the Riemann zeta function, they are Dirichlet series with analytic continuation and functional equations, having applications to analytic number theory. By contrast, these Weyl group multiple Dirichlet series may be functions of several complex variables and their groups of functional equations may be arbitrary finite Weyl groups. Furthermore, their coefficients are multiplicative up to roots of unity, generalizing the notion of Euler products. This book proves foundational results about these series an

Brubaker, Ben; Friedberg, Solomon

2011-01-01

254

Algebraic Signal Processing Theory: Cooley-Tukey Type Algorithms for DCTs and DSTs

This paper presents a systematic methodology based on the algebraic theory of signal processing to classify and derive fast algorithms for linear transforms. Instead of manipulating the entries of transform matrices, our approach derives the algorithms by stepwise decomposition of the associated signal models, or polynomial algebras. This decomposition is based on two generic methods or algebraic principles that generalize the well-known Cooley-Tukey FFT and make the algorithms' derivations concise and transparent. Application to the 16 discrete cosine and sine transforms yields a large class of fast algorithms, many of which have not been found before.

Pueschel, M; Pueschel, Markus; Moura, Jose M. F.

2007-01-01

255

International Nuclear Information System (INIS)

An attempt has been made to obtain a strategy coherent with the available instruments and that could be implemented with future developments. A calculation methodology was developed for fuel reload in PWR reactors, which evolves cell calculation with the HAMMER-TECHNION code and neutronics calculation with the CITATION code.The management strategy adopted consists of fuel element position changing at the beginning of each reactor cycle in order to decrease the radial peak factor. The bi-dimensional, two group First Order perturbation theory was used for the mathematical modeling. (L.C.J.A.)

256

Chern-Simons and Born-Infeld gravity theories and Maxwell algebras type

Recently it was shown that standard odd- and even-dimensional general relativity can be obtained from a -dimensional Chern-Simons Lagrangian invariant under the algebra and from a -dimensional Born-Infeld Lagrangian invariant under a subalgebra , respectively. Very recently, it was shown that the generalized Inönü-Wigner contraction of the generalized AdS-Maxwell algebras provides Maxwell algebras of types which correspond to the so-called Lie algebras. In this article we report on a simple model that suggests a mechanism by which standard odd-dimensional general relativity may emerge as the weak coupling constant limit of a -dimensional Chern-Simons Lagrangian invariant under the Maxwell algebra type , if and only if . Similarly, we show that standard even-dimensional general relativity emerges as the weak coupling constant limit of a -dimensional Born-Infeld type Lagrangian invariant under a subalgebra of the Maxwell algebra type, if and only if . It is shown that when this is not possible for a -dimensional Chern-Simons Lagrangian invariant under the and for a -dimensional Born-Infeld type Lagrangian invariant under the algebra.

Concha, P. K.; Peñafiel, D. M.; Rodriguez, E. K.; Salgado, P.

2014-02-01

257

Chern-Simons and Born-Infeld gravity theories and Maxwell algebras type

International Nuclear Information System (INIS)

Recently it was shown that standard odd- and even-dimensional general relativity can be obtained from a (2n + 1)-dimensional Chern-Simons Lagrangian invariant under the B2n+1 algebra and from a (2n)-dimensional Born-Infeld Lagrangian invariant under a subalgebra LB2n+1, respectively. Very recently, it was shown that the generalized Inoenue-Wigner contraction of the generalized AdS-Maxwell algebras provides Maxwell algebras of types Mm which correspond to the so-called Bm Lie algebras. In this article we report on a simple model that suggests a mechanism by which standard odd-dimensional general relativity may emerge as the weak coupling constant limit of a (2p + 1)-dimensional Chern-Simons Lagrangian invariant under the Maxwell algebra type M2m+1, if and only if m ? p. Similarly, we show that standard even-dimensional general relativity emerges as the weak coupling constant limit of a (2p)-dimensional Born-Infeld type Lagrangian invariant under a subalgebra LM2m of theMaxwell algebra type, if and only if m ? p. It is shown that when m 2m+1 and for a (2p)-dimensional Born-Infeld type Lagrangian invariant under the LM2m algebra. (orig.)

258

Calculation of Fayet-Iliopoulos D-term in type I string theory revisited: T^6/Z^3 orbifold case

The string one-loop computation of Fayet-Iliopoulos D-term in type I string theory in the case of T^6/Z^3 orbifold compactification associated with annulus (planar) and Mobius strip string worldsheet diagrams is reexamined. The mass extracted from the sum of these amplitudes through a limiting procedure is found to be non-vanishing, which is contrary to the earlier computation. The sum can be made finite by a rescaling of the modular parameter in the closed string channel.

Itoyama, H

2013-01-01

259

The classical Yang-Baxter equation and the associated Yangian symmetry of gauged WZW-type theories

Digital Repository Infrastructure Vision for European Research (DRIVER)

We construct the Lax-pair, the classical monodromy matrix and the corresponding solution of the Yang--Baxter equation, for a two-parameter deformation of the Principal chiral model for a simple group. This deformation includes as a one-parameter subset, a class of integrable gauged WZW-type theories interpolating between the WZW model and the non-Abelian T-dual of the principal chiral model. We derive in full detail the Yangian algebra using two independent methods: by compu...

Itsios, Georgios; Sfetsos, Konstantinos; Siampos, Konstantinos; Torrielli, Alessandro

2014-01-01

260

LRS Bianchi type-II universe with cosmic strings and bulk viscosity in a modified theory of gravity

A locally rotationally symmetric (LRS) Bianchi type-II space-time is considered in the frame work of a modified theory of gravitation proposed by Harko et al. (Phys. Rev. D 84:024020, 2011) when the source for energy momentum tensor is a bulk viscous fluid containing one dimensional cosmic strings. A barotropic equation of state is assumed to get a determinate solution of the field equations. Also, the bulk viscous pressure is assumed to be proportional to the energy density. The physical behavior of the model is also discussed.

Reddy, D. R. K.; Naidu, R. L.; Dasu Naidu, K.; Ram Prasad, T.

2013-07-01

261

On a phase transition of a Kosterlitz-thouless-type in the d=4, U(1)-lattice gauge theory

International Nuclear Information System (INIS)

The d=4, U(1)-lattice gauge theory with the Villain action may be represented as a locally neutral gas of topological (plaquette) charges which interact via a logarithmically confining potential, is shown. Using this representation a renormalization group analysis to show the existence of a phase transition of the Kosterlitz-Thouless-type was performed. An improved hierarchical version of the model which displays (unlike the usual Migdal-Kadanoff approach) a stable line of gaussian fixed points at low temperatures, which should correspond to the usual deconfining region of these systems is presented. (Author)

262

Type IIB String Backgrounds on Parallelizable PP-Waves and Conformal Liouville Theory

Digital Repository Infrastructure Vision for European Research (DRIVER)

The scope of this work concerns the adaptation of the parallelizability pp-wave (Ppp-wave) process to D=10 type IIB string backgrounds in the presence of the non-trivial anti-self dual R-R 5-form $\\QTR{cal}{F}$. This is important in the sense that it gives rise to some unsuspected properties. In fact, exact solutions of type IIB string backgrounds on Ppp-waves are discussed. For the $u$-dependence of the dilaton field $\\Phi $, we establish explicitly a correspondence between...

Hssaini, M.; Sedra, M. B.

2003-01-01

263

Phenomenological theory of size effects in ultrafine ferroelectric particles (PbTiO3-type)

International Nuclear Information System (INIS)

A new phenomenological model is proposed and discussed to study the size effects on phase transitions in PbTiO3-type ferroelectric particles. This model, by taking size effects on the phenomenological Landau-Ginzburg-Devonshire coefficients into consideration, can successfully explain the size effects on Curie temperature, c/a ratio, thermal and dielectric properties of lead-titanate-type ferroelectric particles. Theoretical and experimental results for PbTiO3 fine particles are also compared and discussed. The relationship between the current model and the model of Zhong et al (Phys. Rev. B 50, 698 (1994)) is also presented. (authors)

264

LRS Bianchi type-I cosmological model in f( R, T) theory of gravity

The exact solutions of the field equations in respect of LRS Bianchi type-I space time filled with perfect fluid in the framework of f( R, T) gravity (Harko et al., arXiv:1104.2669v2 [gr-qc], 2011) are derived. The physical behavior of the model is studied. In fact, the possibility of reconstruction of the LRS Bianchi type-I cosmology with an appropriate choice of a function f( T) has been proved in f( R, T) gravity.

Adhav, K. S.

2012-06-01

265

International Nuclear Information System (INIS)

We studied Faujasite type molecular sieves by using Fermi Dirac statistics and the quantum theory of dielectricity. We developed an empirical relationship for quantum capacitance which follows an inverse Gaussian profile in the frequency range of 66 Hz - 3 MHz. We calculated quantum capacitance, sample crystal momentum, charge quantization and quantized energy of Faujasite type molecular sieves in the frequency range of 0.1 Hz - 10/sup 4/ MHz. Our calculations for diameter of sodalite and super-cages of Faujasite type molecular sieves are in agreement with experimental results reported in this manuscript. We also calculated quantum polarizability, quantized molecular field, orientational polarizability and deformation polarizability by using experimental results of Ligia Frunza etal. The phonons are over damped in the frequency range 0.1 Hz - 10 kHz and become a source for producing cages in the Faujasite type molecular sieves. Ion exchange recovery processes occur due to over damped phonon excitations in Faujasite type molecular sieves and with increasing temperatures. (author)

266

Efficient quantification of non-gaussian spin distributions.

We study theoretically and experimentally the quantification of non-gaussian distributions via nondestructive measurements. Using the theory of cumulants, their unbiased estimators, and the uncertainties of these estimators, we describe a quantification which is simultaneously efficient, unbiased by measurement noise, and suitable for hypothesis tests, e.g., to detect nonclassical states. The theory is applied to cold 87Rb spin ensembles prepared in non-gaussian states by optical pumping and measured by nondestructive Faraday rotation probing. We find an optimal use of measurement resources under realistic conditions, e.g., in atomic ensemble quantum memories. PMID:22681075

Dubost, B; Koschorreck, M; Napolitano, M; Behbood, N; Sewell, R J; Mitchell, M W

2012-05-01

267

Chern-Simons and Born-Infeld gravity theories and Maxwell algebras type

Energy Technology Data Exchange (ETDEWEB)

Recently it was shown that standard odd- and even-dimensional general relativity can be obtained from a (2n + 1)-dimensional Chern-Simons Lagrangian invariant under the B{sub 2n+1} algebra and from a (2n)-dimensional Born-Infeld Lagrangian invariant under a subalgebra L{sup B{sub 2}{sub n}{sub +}{sub 1}}, respectively. Very recently, it was shown that the generalized Inoenue-Wigner contraction of the generalized AdS-Maxwell algebras provides Maxwell algebras of types M{sub m} which correspond to the so-called B{sub m} Lie algebras. In this article we report on a simple model that suggests a mechanism by which standard odd-dimensional general relativity may emerge as the weak coupling constant limit of a (2p + 1)-dimensional Chern-Simons Lagrangian invariant under the Maxwell algebra type M{sub 2m+1}, if and only if m ? p. Similarly, we show that standard even-dimensional general relativity emerges as the weak coupling constant limit of a (2p)-dimensional Born-Infeld type Lagrangian invariant under a subalgebra L{sup M{sub 2}{sub m}} of theMaxwell algebra type, if and only if m ? p. It is shown that when m < p this is not possible for a (2p+1)-dimensional Chern-Simons Lagrangian invariant under the M{sub 2m+1} and for a (2p)-dimensional Born-Infeld type Lagrangian invariant under the L{sup M{sub 2}{sub m}} algebra. (orig.)

Concha, P.K.; Penafiel, D.M.; Rodriguez, E.K.; Salgado, P. [Universidad de Concepcion, Departamento de Fisica, Concepcion (Chile)

2014-02-15

268

Extension Theory and Krein-type Resolvent Formulas for Nonsmooth Boundary Value Problems

DEFF Research Database (Denmark)

The theory of selfadjoint extensions of symmetric operators, and more generally the theory of extensions of dual pairs, was implemented some years ago for boundary value problems for elliptic operators on smooth bounded domains. Recently, the questions have been taken up again for nonsmooth domains. In the present work we show that pseudodifferential methods can be used to obtain a full characterization, including Kre?n resolvent formulas, of the realizations of nonselfadjoint second-order operators on C32+? domains; more precisely, we treat domains with Bp,232-smoothness and operators with Hq1-coefficients, for suitable p>2(n?1)p>2(n?1) and q>nq>n. The advantage of the pseudodifferential boundary operator calculus is that the operators are represented by a principal part and a lower-order remainder, leading to regularity results; in particular we analyze resolvents, Poisson solution operators and Dirichlet-to-Neumann operators in this way, also in Sobolev spaces of negative order.

Abels, Helmut; Grubb, Gerd

2014-01-01

269

International Nuclear Information System (INIS)

We investigate the origin of phenomenologically interesting small Yukawa couplings in type-I string theory. Utilising the framework of intersecting sets of D9 and orthogonal D5 branes we demonstrate the connection between extra dimensional volumes and Yukawa couplings. For example, we show that extra dimensions with inverse lengths of 108 GeV can lead to 10-10 Yukawa couplings. String selection rules, arising from the D-Brane setup, impose non-trivial constraints on the set of allowed superpotentials. As a phenomenological application of these results we construct a type-I string model of inflationary particle physics which involves small Yukawa couplings of order 10-10, and simultaneously solves the strong CP and ? problem of the MSSM, via the vacuum expectation value of the inflaton field

270

Theory of persistent, p-type, metallic conduction in c-GeTe

International Nuclear Information System (INIS)

It has been known for over twenty years that rhombohedral c-germanium telluride is predicted to be a narrow gap semiconductor. However, it always displays p-type metallic conduction. This behaviour is also observed in other chalcogenide materials, including Ge2Sb2Te5, commonly used for optically and electrically switched, non-volatile memory, and so is of great interest. We present a theoretical study of the electronic structure of the perfect crystal and of the formation energies of germanium/tellurium vacancy and antisite defects in rhombohedral germanium telluride. We find that germanium vacancies are by far the most readily formed defect, independent of Fermi level and of growth ambient. Moreover, we predict that the perfect crystal is thermodynamically unstable. Thus, the predicted large equilibrium densities of the germanium vacancy of ?5 x 1019 cm-3 results in a partially filled valence band and in the observed p-type conductivity. (letter to the editor)

271

A constrained theory of non-BCS type superconductivity in gapped Graphene

We show that gapped Graphene, with a local constraint that current arising from the two valley fermions are exactly equal, shows a non-BCS type superconductivity. Unlike the conventional mechanisms, this superconductivity phenomenon does not require any pairing. We estimate the critical temperature for superconducting-to-normal transition via Berezinskii-Kosterlitz-Thouless mechanism, and find that it is proportional to the gap.

Vyas, Vivek M

2011-01-01

272

Ginzburg-Landau theory of two-band superconductors: Absence of type-1.5 superconductivity

International Nuclear Information System (INIS)

It is shown that within the Ginzburg-Landau (GL) approximation the order parameters ?1(r,T) and ?2(r,T) in two-band superconductors vary on the same length scale, the difference in zero-T coherence lengths ?0? ? (hbar)?F/??(0), ? = 1,2 notwithstanding. This amounts to a single physical GL parameter ? and the classic GL dichotomy: ? 1/?2 for type II.

273

Renormalizations and Rigidity Theory for Circle Homeomorphisms with Singularities of the Break Type

Circle homeomorphisms with singularities of the break type are considered in the case when rotation numbers have periodic continued fraction expansion. We establish hyperbolicity for renormalizations and then use it in order to prove the following rigidity result. Namely, we show that any two homeomorphisms with a single break point are smoothly conjugate to each other provided they have the same quadratic irrational rotation number and the same ``size'' of a break.

Khanin, K.; Khmelev, D.

274

Theory of the normal modes of vibrations in the lanthanide type crystals

For the lanthanide type crystals, a vast and rich, though incomplete amount of experimental data has been accumulated, from linear and non linear optics, during the last decades. The main goal of the current research work is to report a new methodology and strategy to put forward a more representative approach to account for the normal modes of vibrations for a complex N-body system. For illustrative purposes, the chloride lanthanide type crystals Cs2NaLnCl6 have been chosen and we develop new convergence tests as well as a criterion to deal with the details of the F-matrix (potential energy matrix). A novel and useful concept of natural potential energy distributions (NPED) is introduced and examined throughout the course of this work. The diagonal and non diagonal contributions to these NPED-values, are evaluated for a series of these crystals explicitly. Our model is based upon a total of seventy two internal coordinates and ninety eight internal Hooke type force constants. An optimization mathematical procedure is applied with reference to the series of chloride lanthanide crystals and it is shown that the strategy and model adopted is sound from both a chemical and a physical viewpoints. We can argue that the current model is able to accommodate a number of interactions and to provide us with a very useful physical insight. The limitations and advantages of the current model and the most likely sources for improvements are discussed in detail.

Acevedo, Roberto; Soto-Bubert, Andres

2008-11-01

275

Theory of the normal modes of vibrations in the lanthanide type crystals

International Nuclear Information System (INIS)

For the lanthanide type crystals, a vast and rich, though incomplete amount of experimental data has been accumulated, from linear and non linear optics, during the last decades. The main goal of the current research work is to report a new methodology and strategy to put forward a more representative approach to account for the normal modes of vibrations for a complex N-body system. For illustrative purposes, the chloride lanthanide type crystals Cs2NaLnCl6 have been chosen and we develop new convergence tests as well as a criterion to deal with the details of the F-matrix (potential energy matrix). A novel and useful concept of natural potential energy distributions (NPED) is introduced and examined throughout the course of this work. The diagonal and non diagonal contributions to these NPED-values, are evaluated for a series of these crystals explicitly. Our model is based upon a total of seventy two internal coordinates and ninety eight internal Hooke type force constants. An optimization mathematical procedure is applied with reference to the series of chloride lanthanide crystals and it is shown that the strategy and model adopted is sound from both a chemical and a physical viewpoints. We can argue that the current model is able to accommodate a number of interactions and to provide us with a very useful physical insight. The limitations and advantages of the current model and the most likely sources for improvements are discussed in detaies for improvements are discussed in detail.

276

Chern-Simons and Born-Infeld gravity theories and Maxwell algebras type

Recently was shown that standard odd and even-dimensional General Relativity can be obtained from a $(2n+1)$-dimensional Chern-Simons Lagrangian invariant under the $B_{2n+1}$ algebra and from a $(2n)$-dimensional Born-Infeld Lagrangian invariant under a subalgebra $\\cal{L}^{B_{2n+1}}$ respectively. Very Recently, it was shown that the generalized In\\"on\\"u-Wigner contraction of the generalized AdS-Maxwell algebras provides Maxwell algebras types $\\cal{M}_{m}$ which correspond to the so called $B_{m}$ Lie algebras. In this article we report on a simple model that suggests a mechanism by which standard odd-dimensional General Relativity may emerge as a weak coupling constant limit of a $(2p+1)$-dimensional Chern-Simons Lagrangian invariant under the Maxwell algebra type $\\cal{M}_{2m+1}$, if and only if $m\\geq p$. Similarly, we show that standard even-dimensional General Relativity emerges as a weak coupling constant limit of a $(2p)$-dimensional Born-Infeld type Lagrangian invariant under a subalgebra $\\cal{L}...

Concha, P K; Rodríguez, E K; Salgado, P

2014-01-01

277

Topic-Focus Structure and Quantification of Dou 'all'

Directory of Open Access Journals (Sweden)

Full Text Available This paper examines a type of dou quantification found in wh-questions such as ta dou mai le shenme? ‘What are all the things that he bought?’ This type is different from the well-known dou quantification in that the leftness condition cannot be applied to the former. I propose that the former type of quantification is subject to the topic-focus structure rather than to the syntactic structure, which means that the domain of the quantification is determined in relation to 'old' and 'new' information of a sentence. Sentences including dou can be divided into topic and focus, and each part is mapped onto the restrictor and the nuclear scope in a tripartite structure of dou quantification. This analysis accounts for the reason why a list answer is appropriate to questions with dou, why wh-words in the questions cannot be quantity expressions, and why wh-words should either have a plural interpretation or take the plural form. This analysis also explains the distribution of dou, i.e., dou should c-command a focused phrase. Finally, I point out that the analysis can extend to declaratives which are rare but still observable, and that the two types of dou quantification can arise simultaneously.

Joonho Shin

2007-06-01

278

Advances in forensic DNA quantification: A review.

This review focuses upon a critical step in forensic biology: detection and quantification of human DNA from biological samples. Determination of the quantity and quality of human DNA extracted from biological evidence is important for several reasons. Firstly, depending on the source and extraction method, the quality (purity and length), and quantity of the resultant DNA extract can vary greatly. This affects the downstream method as the quantity of input DNA and its relative length can determine which genotyping procedure to use-standard short-tandem repeat (STR) typing, mini-STR typing or mitochondrial DNA sequencing. Secondly, because it is important in forensic analysis to preserve as much of the evidence as possible for retesting, it is important to determine the total DNA amount available prior to utilizing any destructive analytical method. Lastly, results from initial quantitative and qualitative evaluations permit a more informed interpretation of downstream analytical results. Newer quantitative techniques involving real-time PCR can reveal the presence of degraded DNA and PCR inhibitors, that provide potential reasons for poor genotyping results and may indicate methods to use for downstream typing success. In general, the more information available, the easier it is to interpret and process the sample resulting in a higher likelihood of successful DNA typing. The history of the development of quantitative methods has involved two main goals-improving precision of the analysis and increasing the information content of the result. This review covers advances in forensic DNA quantification methods and recent developments in RNA quantification. PMID:25088961

Lee, Steven B; McCord, Bruce; Buel, Eric

2014-11-01

279

Predicting interfacial tension between water and nonpolar fluids from a Cahn-type theory.

We propose an accurate method to predict interfacial tension between water and nonpolar fluids by using Cahn gradient theory. The only necessary elements are (i) a water contact energy function and (ii) an equation of state (EoS) for the nonpolar fluid, chosen here as the Peng-Robinson EoS. The contact energy, a function of the fluid (adsorbate) surface density, is related to interfacial tension (IFT) by means of the Gibbs adsorption equation. Examining a large number of IFT data, we observe that the water contact energy is a universal function of adsorbate's surface density when proper scaling variables are used: it depends neither on adsorbate nor on temperature. A corresponding-states principle appears to govern the interfacial behavior between water and any nonpolar compound that is sparingly soluble in water. A predictive method (without any adjustable parameter) is therefore available for estimating IFT between water and any nonpolar fluid, whether the fluid is in supercritical or in subcritical states. The method performs well when the adsorbate is sparingly soluble in water, but slightly overestimates IFTs when the adsorbate's solubility in water is significant (e.g., CO2 and H2S). A similar behavior should also hold for interfaces involving a solid substrate. PMID:17973408

Shah, Virenkumar; Broseta, Daniel

2007-12-01

280

A numerical method is proposed for efficient solution of scattering from objects with weakly perturbed surfaces by combining the perturbation theory, transformation electromagnetics and the finite element method. A transformation medium layer is designed over the smooth surface, and the material parameters of the medium are determined by means of a coordinate transformation that maps the smooth surface to the perturbed surface. The perturbed fields within the domain are computed by employing the material parameters and the fields of the smooth surface as source terms in the Helmholtz equation. The main advantage of the proposed approach is that if repeated solutions are needed (such as in Monte Carlo technique or in optimization problems requiring multiple solutions for a set of perturbed surfaces), computational resources considerably decrease because a single mesh is used and the global matrix is formed only once. Only the right hand side vector is changed with respect to the perturbed material parameters corresponding to each of the perturbed surfaces. The technique is validated via finite element simulations.

Kuzuoglu, Mustafa; Ozgun, Ozlem

2014-10-01

281

C/O ratio in N type carbon stars: observations and the theory

International Nuclear Information System (INIS)

Frequency distribution for the C/O ratio in Ntype carbon stars in simulated populations of asymptotic giant branch for Salpeter initial mass function, constant stellar production rate history and coefficient ?=1 in Reimers formula of mass loss rate was obtained. This distribution was compared with observed ones. The best agreement was obtained with C/O values from the work of Eglitis (1988). In the Galaxy N type stars may form only from the stars with initial mass less than 1.5 MSun due to relatively small initial heavy element abundance in these stars; this is the main reason of the absence of carbon stars in open clusters in the Galaxy

282

Towards an understanding of Type Ia supernovae from a synthesis of theory and observations

Motivated by the fact that calibrated light curves of Type Ia supernovae (SNe Ia) have become a major tool to determine the expansion history of the Universe, considerable attention has been given to, both, observations and models of these events over the past 15 years. Here, we summarize new observational constraints, address recent progress in modeling Type Ia supernovae by means of three-dimensional hydrodynamic simulations, and discuss several of the still open questions. It will be be shown that the new models have considerable predictive power which allows us to study observable properties such as light curves and spectra without adjustable non-physical parameters. This is a necessary requisite to improve our understanding of the explosion mechanism and to settle the question of the applicability of SNe Ia as distance indicators for cosmology. We explore the capabilities of the models by comparing them with observations and we show how such models can be applied to study the origin of the diversity of S...

Hillebrandt, W; Röpke, F K; Ruiter, A J

2013-01-01

283

A Pieri-type formula for the K-theory of a flag manifold

We derive explicit Pieri-type multiplication formulas in the Grothendieck ring of a flag variety. These expand the product of an arbitrary Schubert class and a special Schubert class in the basis of Schubert classes. These special Schubert classes are indexed by a cycle which has either the form (k-p+1,k-p+2,...,k+1) or the form (k+p,k+p-1,...,k), and are pulled back from a Grassmannian projection. Our formulas are in terms of certain labeled chains in the k-Bruhat order on the symmetric group and are combinatorial in that they involve no cancellations. We also show that the multiplicities in the Pieri formula are naturally certain binomial coefficients.

Lenart, C; Lenart, Cristian; Sottile, Frank

2004-01-01

284

Quantum models for synchronously pumped type I optical parametric oscillators (SPOPO) are presented. The study of the dynamics of SPOPOs, which typically involves millions of coupled signal longitudinal modes, is significantly simplified when one considers the ?supermodes?, which are independent linear superpositions of all the signal modes diagonalizing the parametric interaction. In terms of these supermodes the SPOPO dynamics becomes that of about a hundred of independent, single mode degenerate OPOs, each of them being a squeezer. One derives a general expression for the squeezing spectrum measured in a balanced homodyne detection experiment, valid for any temporal shape of the local oscillator. Realistic cases are then studied using both analytical and numerical methods: the oscillation threshold is derived, and the spectral and temporal shapes of the squeezed supermodes are characterized.

Patera, Giuseppe; Fabre, Claude; De Valcarcel, German J

2009-01-01

285

Secret symmetries of type IIB superstring theory on Ad{{S}_{3}} × {{S}^{3}} × {{M}^{4}}

We establish features of so-called Yangian secret symmetries for AdS3 type IIB superstring backgrounds, thus verifying the persistence of such symmetries to this new instance of the AdS/CFT correspondence. Specifically, we find two a priori different classes of secret symmetry generators. One class of generators, anticipated from the previous literature, is more naturally embedded in the algebra governing the integrable scattering problem. The other class of generators is more elusive and somewhat closer in its form to its higher-dimensional AdS5 counterpart. All of these symmetries respect left-right crossing. In addition, by considering the interplay between left and right representations, we gain a new perspective on the AdS5 case. We also study the RTT-realisation of the Yangian in AdS3 backgrounds, thus establishing a new incarnation of the Beisert–de Leeuw construction.

Pittelli, Antonio; Torrielli, Alessandro; Wolf, Martin

2014-11-01

286

DEFF Research Database (Denmark)

Human T-lymphotropic virus type I (HTLV-I) provirus load was examined in a cohort of a population in Guinea-Bissau among whom human immunodeficiency virus (HIV) type 2 is endemic. Geometric mean of HIV-2 RNA load among HTLV-I-coinfected subjects was significantly lower than that in subjects infected with HIV-2 alone (212 vs. 724 copies/mL; P=.02). Adjusted for age, sex, and HIV status, the risk of death increased with HTLV-I provirus load; mortality hazard ratio was 1.59 for each log10 increase in HTLV-I provirus copies (P=.038). There is no enhancing effect of HTLV-I coinfection on HIV-2 disease, but high HTLV-I provirus loads may contribute to mortality.

Ariyoshi, K; Berry, N

2003-01-01

287

SERS Quantification of Entacapone Isomers

Raman spectroscopy, due to its non-destructive character and speed, has found widespread use in pharmaceutical applications [1]. It is also being used for quantifying various isomer mixtures, best known being the quantification of xylene isomers [2-3]. Solid-state isomer quantification of entacapone was earlier reported [4]. Here, we report quantification of isomer mixture of an active pharmaceutical substance, in solution, by SERS.

Markovi?, Marina; Biljan, Tomislav

2010-08-01

288

Development of flow network analysis code for block type VHTR core by linear theory method

Energy Technology Data Exchange (ETDEWEB)

VHTR (Very High Temperature Reactor) is high-efficiency nuclear reactor which is capable of generating hydrogen with high temperature of coolant. PMR (Prismatic Modular Reactor) type reactor consists of hexagonal prismatic fuel blocks and reflector blocks. The flow paths in the prismatic VHTR core consist of coolant holes, bypass gaps and cross gaps. Complicated flow paths are formed in the core since the coolant holes and bypass gap are connected by the cross gap. Distributed coolant was mixed in the core through the cross gap so that the flow characteristics could not be modeled as a simple parallel pipe system. It requires lot of effort and takes very long time to analyze the core flow with CFD analysis. Hence, it is important to develop the code for VHTR core flow which can predict the core flow distribution fast and accurate. In this study, steady state flow network analysis code is developed using flow network algorithm. Developed flow network analysis code was named as FLASH code and it was validated with the experimental data and CFD simulation results. (authors)

Lee, J. H.; Yoon, S. J. [Dept. of Nuclear Engr., Seoul National Univ., Daehak-dong, Gwanak-gu, Seoul, 151-742 (Korea, Republic of); Park, J. W. [Dept. of Nuclear and Energy Engr, Dongguk Univ., Seokjang-Dong, Gyeongju, Gyeongsangbuk-Do, 780-714 (Korea, Republic of); Park, G. C. [Dept. of Nuclear Engr., Seoul National Univ., Daehak-dong, Gwanak-gu, Seoul, 151-742 (Korea, Republic of)

2012-07-01

289

Flux-induced soft terms on type IIB/F-theory matter curves and hypercharge dependent scalar masses

Closed string fluxes induce generically SUSY-breaking soft terms on supersymmetric type IIB orientifold compactifications with D3/D7 branes. This was studied in the past by inserting those fluxes on the DBI+CS actions for adjoint D3/D7 fields, where D7-branes had no magnetic fluxes. In the present work we generalise those computations to the phenomenologically more relevant case of chiral bi-fundamental fields laying at 7-brane intersections and F-theory local matter curves. We also include the effect of 7-brane magnetic flux as well as more general closed string backgrounds, including the effect of distant -branes. We discuss several applications of our results. We find that squark/slepton masses become in general flux-dependent in F-theory GUT's. Hypercharge-dependent non-universal scalar masses with a characteristic sfermion hierarchy m {/E 2} < m {/L 2} < m {/Q 2} < m {/D 2} < m {/U 2} are obtained. There are also flavor-violating soft terms both for matter fields living at intersecting 7-branes or on D3-branes at singularities. They point at a very heavy sfermion spectrum to avoid FCNC constraints. We also discuss the possible microscopic description of the fine-tuning of the EW Higgs boson in compactifications with a MSSM spectrum.

Cámara, Pablo G.; Ibáñez, Luis E.; Valenzuela, Irene

2014-06-01

290

We consider perturbations of a static and spherically symmetric background endowed with a metric tensor and a scalar field in the framework of the effective field theory of modified gravity. We employ the previously developed 2+1+1 canonical formalism of a double Arnowitt-Deser-Misner (ADM) decomposition of space-time, which singles out both time and radial directions. Our building block is a general gravitational action that depends on scalar quantities constructed from the 2+1+1 canonical variables and the lapse. Variation of the action up to first-order in perturbations gives rise to three independent background equations of motion, as expected from spherical symmetry. The dynamical equations of linear perturbations follow from the second-order Lagrangian after a suitable gauge fixing. We derive conditions for the avoidance of ghosts and Laplacian instabilities for the odd-type perturbations. We show that our results not only incorporates those derived in the most general scalar-tensor theories with second...

Kase, Ryotaro; Tsujikawa, Shinji

2014-01-01

291

Flux-induced Soft Terms on Type IIB/F-theory Matter Curves and Hypercharge Dependent Scalar Masses

Closed string fluxes induce generically SUSY-breaking soft terms on supersymmetric type IIB orientifold compactifications with D3/D7 branes. This was studied in the past by inserting those fluxes on the DBI+CS actions for adjoint D3/D7 fields, where D7-branes had no magnetic fluxes. In the present work we generalise those computations to the phenomenologically more relevant case of chiral bi-fundamental fields laying at 7-brane intersections and F-theory local matter curves. We also include the effect of 7-brane magnetic flux as well as more general closed string backgrounds, including the effect of distant (anti-)D3-branes. We discuss several applications of our results. We find that squark/slepton masses become in general flux-dependent in F-theory GUT's. Hypercharge-dependent non-universal scalar masses with a characteristic sfermion hierarchy m_E^2 < m_L^2 < m_Q^2 < m_D^2 < m_U^2 are obtained. There are also flavor-violating soft terms both for matter fields living at intersecting 7-branes or ...

Camara, Pablo G; Valenzuela, Irene

2014-01-01

292

International Nuclear Information System (INIS)

We investigate the Bianchi type-I massive string magnetized barotropic perfect fluid cosmological model in Rosen's bimetric theory of gravitation with and without a magnetic field by applying the techniques used by Latelier (1979, 1980) and Stachel (1983). To obtain a deterministic model of the universe, it is assumed that the universe is filled with barotropic perfect fluid distribution. The physical and geometrical significance of the model are discussed. By comparing our model with the model of Bali et al. (2007), it is realized that there are no big-bang and big-crunch singularities in our model and T = 0 is not the time of the big bang, whereas the model of Bali et al. starts with a big bang at T = 0. Further, our model is in agreement with Bali et al. (2007) as time increases in the presence, as well as in the absence, of a magnetic field. (geophysics, astronomy, and astrophysics)

293

LRS Bianchi type-II bulk viscous cosmic string model in a scale covariant theory of gravitation

A locally rotationally symmetric(LRS) Bianchi type-II space-time is considered in the frame work of a modified theory of gravitation proposed by Canuto et al. (Phys. Rev. Lett. 39:429, 1977) when the source for energy momentum tensor is a bulk viscous fluid containing one dimensional cosmic strings. A special law of variation for Hubble's parameter proposed by Bermann (Nuovo Cimento B 74:182, 1983) is used to obtain determinate solution of the field equations. We have also used the barotropic equation of state and the bulk viscous pressure is assumed to be proportional to the energy density. The physical and kinematical properties of the model are also discussed.

Reddy, D. R. K.; Naidu, R. L.; Ramprasd, T.; Ramana, K. V.

2013-11-01

294

International Nuclear Information System (INIS)

We consider rotating strings and D2-branes on type IIA background, which arises as dimensional reduction of M-theory on manifold of G2 holonomy, dual to N = 1 gauge theory in four dimensions. We obtain exact solutions and explicit expressions for the conserved charges. By taking the semiclassical limit, we show that the rotating strings can reproduce only one type of semiclassical behavior, exhibited by rotating M2-branes on G2 manifolds. Our further investigation leads to the conclusion that the rotating D2-branes reproduce two types of the semiclassical energy-charge relations known for membranes in eleven dimensions

295

Here we propose a scenario according to which a generic self-organized critical (SOC) system can be looked upon as a Witten-type topological field theory (W-TFT) with spontaneously broken BRST-symmetry. One of the conditions for the SOC is the slow external driving that unambiguously suggests the Stratanovich interpretation of noise in the corresponding stochastic differential equation (SDE). This necessitates the use of the Parisi-Wu quantization of the SDE leading to a model with a BRST-exact action, \\emph i.e., to a W-TFT. For a general SDE with a mixed-type drift term (Langevin + Hamilton parts), the BRST-symmetry is spontaneously broken and there is the Goldstone mode of Fadeev-Popov ghosts. In the low-energy/long-wavelength limit, the ghosts represent instanton/avalanche modulii and being gapless are responsible for the critical distribution of avalanches. The above arguments are robust against a moderate variation of the SDE's parameters and the criticality is "self-tuned". Our proposition suggests tha...

Ovchinnikov, Igor V

2011-01-01

296

Level 2 probabilistic event analyses and quantification

International Nuclear Information System (INIS)

In this paper an example of quantification of a severe accident phenomenological event is given. The performed analysis for assessment of the probability that the debris released from the reactor vessel was in a coolable configuration in the lower drywell is presented. It is also analysed the assessment of the type of core/concrete attack that would occur. The coolability of the debris ex-vessel evaluation by an event in the Simplified Boiling Water Reactor (SBWR) Containment Event Tree (CET) and a detailed Decomposition Event Tree (DET) developed to aid in the quantification of this CET event are considered. The headings in the DET selected to represent plant physical states (e.g., reactor vessel pressure at the time of vessel failure) and the uncertainties associated with the occurrence of critical physical phenomena (e.g., debris configuration in the lower drywell) considered important to assessing whether the debris was coolable or not coolable ex-vessel are also discussed

297

Correct DNA quantification is an essential part to obtain reliable STR typing results. Forensic DNA analysts often use commercial kits for DNA quantification; among them, real-time-based DNA quantification kits are most frequently used. Incorrect DNA quantification due to the presence of PCR inhibitors may affect experiment results. In this study, we examined the alteration degree of DNA quantification results estimated in DNA samples containing a PCR inhibitor by using a Quantifiler® Human DNA Quantification kit. For experiments, we prepared approximately 0.25 ng/?l DNA samples containing various concentrations of humic acid (HA). The quantification results were 0.194-0.303 ng/?l at 0-1.6 ng/?l HA (final concentration in the Quantifiler reaction) and 0.003-0.168 ng/?l at 2.4-4.0 ng/?l HA. Most DNA quantity was undetermined when HA concentration was higher than 4.8 ng/?l HA. The C (T) values of an internal PCR control (IPC) were 28.0-31.0, 36.5-37.1, and undetermined at 0-1.6, 2.4, and 3.2 ng/?l HA. These results indicate that underestimated DNA quantification results may be obtained in the DNA sample with high C (T) values of IPC. Thus, researchers should carefully interpret the DNA quantification results. We additionally examined the effects of HA on the STR amplification by using an Identifiler® kit and a MiniFiler™ kit. Based on the results of this study, it is thought that a better understanding of various effects of HA would help researchers recognize and manipulate samples containing HA. PMID:21912926

Seo, Seung Bum; Lee, Hye Young; Zhang, Ai Hua; Kim, Hye Yeon; Shin, Dong Hoon; Lee, Soong Deok

2012-11-01

298

Accident sequence quantification with KIRAP

Energy Technology Data Exchange (ETDEWEB)

The tasks of probabilistic safety assessment(PSA) consists of the identification of initiating events, the construction of event tree for each initiating event, construction of fault trees for event tree logics, the analysis of reliability data and finally the accident sequence quantification. In the PSA, the accident sequence quantification is to calculate the core damage frequency, importance analysis and uncertainty analysis. Accident sequence quantification requires to understand the whole model of the PSA because it has to combine all event tree and fault tree models, and requires the excellent computer code because it takes long computation time. Advanced Research Group of Korea Atomic Energy Research Institute(KAERI) has developed PSA workstation KIRAP(Korea Integrated Reliability Analysis Code Package) for the PSA work. This report describes the procedures to perform accident sequence quantification, the method to use KIRAP`s cut set generator, and method to perform the accident sequence quantification with KIRAP. (author). 6 refs.

Kim, Tae Un; Han, Sang Hoon; Kim, Kil You; Yang, Jun Eon; Jeong, Won Dae; Chang, Seung Cheol; Sung, Tae Yong; Kang, Dae Il; Park, Jin Hee; Lee, Yoon Hwan; Hwang, Mi Jeong

1997-01-01

299

We have obtained and presented spatially homogeneous Bianchi type-II, VIII & IX cosmological models with strange quark matter attached to string cloud in Brans and Dicke (Phys. Rev. C 71:054905, 1961) scalar tensor theory and general theory of gravitation. Some important features of the models, thus obtained, have been discussed. We noticed that these universes always expand isotropically and the presence of scalar field doesn't affect the geometry of the space-time but changes the matter distribution.

Rao, V. U. M.; Sireesha, K. V. S.

2013-04-01

300

Validated method for phytohormone quantification in plants.

Phytohormones are long time known as important components of signaling cascades in plant development and plant responses to various abiotic and biotic challenges. Quantifications of phytohormone levels in plants are typically carried out using GC or LC-MS/MS systems, due to their high sensitivity, specificity, and the fact that not much sample preparation is needed. However, mass spectrometer-based analyses are often affected by the particular sample type (different matrices), extraction procedure, and experimental setups, i.e., the chromatographic separation system and/or mass spectrometer analyser (Triple-quadrupole, Iontrap, TOF, Orbitrap). For these reasons, a validated method is required in order to enable comparison of data that are generated in different laboratories, under different experimental set-ups, and in different matrices. So far, many phytohormone quantification studies were done using either QTRAP or Triple-quadrupole mass spectrometers. None of them was performed under the regime of a fully-validated method. Therefore, we developed and established such validated method for quantification of stress-related phytohormones such as jasmonates, abscisic acid, salicylic acid, IAA, in the model plant Arabidopsis thaliana and the fruit crop Citrus sinensis, using an Iontrap mass spectrometer. All parameters recommended by FDA (US Food and Drug Administration) or EMEA (European Medicines Evaluation Agency) for validation of analytical methods were evaluated: sensitivity, selectivity, repeatability and reproducibility (accuracy and precision). PMID:25206356

Almeida Trapp, Marília; De Souza, Gezimar D; Rodrigues-Filho, Edson; Boland, William; Mithöfer, Axel

2014-01-01

301

Validated method for phytohormone quantification in plants

Phytohormones are long time known as important components of signaling cascades in plant development and plant responses to various abiotic and biotic challenges. Quantifications of phytohormone levels in plants are typically carried out using GC or LC-MS/MS systems, due to their high sensitivity, specificity, and the fact that not much sample preparation is needed. However, mass spectrometer-based analyses are often affected by the particular sample type (different matrices), extraction procedure, and experimental setups, i.e., the chromatographic separation system and/or mass spectrometer analyser (Triple-quadrupole, Iontrap, TOF, Orbitrap). For these reasons, a validated method is required in order to enable comparison of data that are generated in different laboratories, under different experimental set-ups, and in different matrices. So far, many phytohormone quantification studies were done using either QTRAP or Triple-quadrupole mass spectrometers. None of them was performed under the regime of a fully-validated method. Therefore, we developed and established such validated method for quantification of stress-related phytohormones such as jasmonates, abscisic acid, salicylic acid, IAA, in the model plant Arabidopsis thaliana and the fruit crop Citrus sinensis, using an Iontrap mass spectrometer. All parameters recommended by FDA (US Food and Drug Administration) or EMEA (European Medicines Evaluation Agency) for validation of analytical methods were evaluated: sensitivity, selectivity, repeatability and reproducibility (accuracy and precision).

Almeida Trapp, Marilia; De Souza, Gezimar D.; Rodrigues-Filho, Edson; Boland, William; Mithofer, Axel

2014-01-01

302

Scaling theory in Tomonaga-Luttinger liquid with $1/r^\\beta$ type long-range interactions

We discuss effects of $1/r^\\beta$ type long-range (LR) interactions in a tight-binding model by utilizing the bosonization technique, renormalization group and conformal field theory (CFT). We obtain the low energy action known for Kibble's model which generates the mass gap in 3 dimension when $\\beta =1$, the Coulomb force case. In one dimension, the dispersion relations predict that the system remains gapless even for $\\beta =1$ and the existences of Tomonaga-Luttinger liquid (TLL) when $\\beta > 1$. When $\\beta =1$, the LR interactions break TLL in the long wavelength limits, even if the strength is very small. We make the more precise arguments from the stand point of the renormalization group and CFT. Finally we derive the accurate finite size scaling of energies and thermodynamics. Moreover we proceed to numerical calculations, considering the LR umklapp process terms. We conclude that the TLL phase become wider in the strength space of interactions as the power $\\beta$ approaches to 1.

Inoue, H

2001-01-01

303

Session Types = Intersection Types + Union Types

We propose a semantically grounded theory of session types which relies on intersection and union types. We argue that intersection and union types are natural candidates for modeling branching points in session types and we show that the resulting theory overcomes some important defects of related behavioral theories. In particular, intersections and unions provide a native solution to the problem of computing joins and meets of session types. Also, the subtyping relation turns out to be a pre-congruence, while this is not always the case in related behavioral theories.

Padovani, Luca

2011-01-01

304

We study some aspects of short-distance interaction between parallel D3-branes in type 0 string theory as described by the corresponding world-volume gauge theory. We compute the one-loop effective potential in the non-supersymmetric SU(N) x SU(N) gauge theory (which is a Z_2 projection of the U(2N) n=4 SYM theory) representing dyonic branes composed of N electric and N magnetic D3-branes. The branes of the same type repel at short distances, but an electric and a magnetic brane attract, and the forces between self-dual branes cancel. The self-dual configuration (with the positions of the electric and the magnetic branes, i.e. the diagonal entries of the adjoint scalar fields, being the same) is stable against separation of one electric or one magnetic brane, but is unstable against certain modes of separation of several same-type branes. This instability should be suppressed in the large N limit, i.e. should be irrelevant for the large N CFT interpretation of the gauge theory suggested in hep-th/9901101.

Tseytlin, Arkady A

1999-01-01

305

Unstable non-BPS D-branes of type-II string theories in light-cone Green-Schwarz formalism

International Nuclear Information System (INIS)

The problem of describing the boundary states of unstable non-BPS D-branes of type-II string theories in light-cone Green-Schwarz (GS) formalism is addressed. Regarding the type II theories in light-cone gauge as different realizations of the SO-circumflex(8)k=1 Kac-Moody algebra, the non-BPS D-brane boundary states of these theories are given in terms of the relevant Ishibashi states constructed in this current algebra. Using the expressions for the current modes in terms of the GS variables it is straightforward to reexpress the boundary states in the GS formalism. The problem that remains is the lack of manifest SO(8) covariance in these expressions. We also derive the various known expressions for the BPS and non-BPS D-brane boundary states by starting with the current algebra Ishibashi states

306

Quantum non-equilibrium and relaxation to equilibrium for a class of de Broglie-Bohm-type theories

International Nuclear Information System (INIS)

The de Broglie-Bohm theory is about non-relativistic point-particles that move deterministically along trajectories. The theory reproduces the predictions of standard quantum theory, given that the distribution of particles over an ensemble of systems, all described by the same wavefunction ?, equals the quantum equilibrium distribution |?|2. Numerical simulations done by Valentini and Westman (2005 Proc. R. Soc. A 461 253) have illustrated that non-equilibrium particle distributions may relax to quantum equilibrium after some time. Here we consider non-equilibrium distributions and their relaxation properties for a particular class of trajectory theories (first studied in detail by Deotto and Ghirardi (1998 Found. Phys. 28 1)) that are empirically equivalent to the de Broglie-Bohm theory in quantum equilibrium. In the examples we studied of such theories, we found a speed-up of the relaxation, compared to the ordinary de Broglie-Bohm theory. Hence non-equilibrium predictions that depend strongly on relaxation properties, such as those studied recently by Valentini, may vary across different trajectory theories. As such, these theories might be experimentally distinguishable.

307

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Treatment recommendations for prevention of type 2 diabetes complications often require radical and life-long health behaviour changes. Observational studies based on Self-determination theory (SDT propose substantial factors for the maintenance of behaviour changes and concomitant well-being, but experimental research is needed to develop and evaluate SDT-based interventions. The aims of this paper were to describe 1 the design of a trial assessing the effectiveness of a training course for practice-nurses in autonomy support on patient-perceived motivation, HbA1, cholesterol, and well-being among a diabetes population, 2 the actual intervention to a level of detail that allows its replication, and 3 the connection between SDT recommendations for health care-provider behaviour and the content of the training course. Methods/Design The study is a cluster-randomised pragmatic trial including 40 Danish general practices with nurse-led diabetes consultations, and the associated diabetes population. The diabetes population was identified by registers (n = 4034. The intervention was a 16-hour course with interactive training for practice nurses. The course was delivered over 4 afternoons at Aarhus University and one 1/2 hour visit to the practice by one of the course-teachers over a period of 10 months (0, 2, 5, 10 mths.. The intervention is depicted by a PaT Plot showing the timeline and the characteristics of the intervention components. Effectiveness of the intervention will be assessed on the diabetes populations with regard to well-being (PAID, SF-12, HbA1c- and cholesterol-levels, perceived autonomy support (HCCQ, type of motivation (TSRQ, and perceived competence for diabetes care (PCD 15-21 months after the core course; the completion of the second course afternoon. Data will be retrieved from registers and by questionnaires. Discussion Challenges and advantages of the pragmatic design are discussed. In a real-world setting, this study will determine the impact on motivation, HbA1c, cholesterol, and well-being for people with diabetes by offering a training course in autonomy support to practice-nurses from general practices with nurse-led consultations. Trial registration ClinicalTrials.gov: NCT01187069

Juul Lise

2011-11-01

308

Because it focuses on the interactions between students and their environments, Holland's theory of vocational choice provides a powerful framework for studying college experiences. The present study assessed the relative merits of psychological and sociological interpretations of Holland's theory by examining the relationships among students' …

Pike, Gary R.

2006-01-01

309

On a singular Fredholm-type integral equation arising in N=2 super Yang-Mills theories

In this work we study the Nekrasov-Shatashvili limit of the Nekrasov instanton partition function of Yang-Mills field theories with N=2 supersymmetry and gauge group SU(n). The theories are coupled with fundamental matter. The equation that determines the density of eigenvalues at the leading order in the saddle-point approximation is exactly solved. The dominating contribution to the instanton free energy is computed. The requirement that this energy is finite imposes quantization conditions on the parameters of the theory that are in agreement with analogous conditions that have been derived in previous works. Using methods borrowed from the theory of matrix models, a field theoretical expression of the full instanton partition function is derived. It is checked that in the Nekrasov-Shatashvili (thermodynamic) limit the action of the field theory obtained in this way reproduces exactly the equation of motion used in the saddle-point calculations.

Ferrari, Franco

2012-01-01

310

On a singular Fredholm-type integral equation arising in N=2 super-Yang–Mills theories

International Nuclear Information System (INIS)

In this work we study the Nekrasov–Shatashvili limit of the Nekrasov instanton partition function of Yang–Mills field theories with N=2 supersymmetry and gauge group SU(Nc). The theories are coupled with Nf flavors of fundamental matter. The equation that determines the density of eigenvalues at the leading order in the saddle-point approximation is exactly solved when Nf=2Nc. The dominating contribution to the instanton free energy is computed. The requirement that this energy is finite imposes quantization conditions on the parameters of the theory that are in agreement with analogous conditions that have been derived in previous works. The instanton energy and thus the instanton contribution to the prepotential of the gauge theory is computed in closed form.

311

On a singular Fredholm-type integral equation arising in N=2 super-Yang-Mills theories

Energy Technology Data Exchange (ETDEWEB)

In this work we study the Nekrasov-Shatashvili limit of the Nekrasov instanton partition function of Yang-Mills field theories with N=2 supersymmetry and gauge group SU(N{sub c}). The theories are coupled with N{sub f} flavors of fundamental matter. The equation that determines the density of eigenvalues at the leading order in the saddle-point approximation is exactly solved when N{sub f}=2N{sub c}. The dominating contribution to the instanton free energy is computed. The requirement that this energy is finite imposes quantization conditions on the parameters of the theory that are in agreement with analogous conditions that have been derived in previous works. The instanton energy and thus the instanton contribution to the prepotential of the gauge theory is computed in closed form.

Ferrari, Franco, E-mail: ferrari@fermi.fiz.univ.szczecin.pl [Institute of Physics and CASA, University of Szczecin, Wielkopolska 15, 70451 Szczecin (Poland); Piatek, Marcin, E-mail: piatek@fermi.fiz.univ.szczecin.pl [Institute of Physics and CASA, University of Szczecin, Wielkopolska 15, 70451 Szczecin (Poland); Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)

2013-01-08

312

Theory and experiment on the time-dependent photovoltaic effect in n-type InSb

International Nuclear Information System (INIS)

Experimental data are presented of the ac photovoltage obtained on InSb metal-insulator-semiconductor (MIS) diodes at about 77 K. These data are compared with a theory of the ac surface photovoltage effect

313

Quantification of Line Tracking Solutions for Automotive Applications

Unlike line tracking in automotive painting applications, line tracking for automotive general assembly applications requires position tracking in order to perform assembly operations to a required assembly tolerance. Line tracking quantification experiments have been designed and conducted for a total of 16 test cases for two line tracking scenarios with three types of line tracking solutions: encoder based tracking, encoder plus static vision based tracking, and the analog sensor-based tracking for general assembly robotic automation. This chapter presents the quantification results, identifies key performance drivers, and illustrates their implications for automotive assembly applications.

Shi, Jane; Rourke, Rick F.; Groll, Dave; Tavora, Peter W.

314

Digital Repository Infrastructure Vision for European Research (DRIVER)

Although neurocognitive impairments in theory of mind and in executive functions have both been hypothesized to play a causal role in autism, there has been little research investigating the explanatory power of these impairments with regard to autistic symptomatology. The present study examined the degree to which individual differences in theory of mind and executive functions could explain variations in the severity of autism symptoms. Participants included 31 verbal, school-aged children ...

Joseph, Robert M.; Tager–flusberg, Helen

2004-01-01

315

A recipe for EFT uncertainty quantification in nuclear physics

Digital Repository Infrastructure Vision for European Research (DRIVER)

The application of effective field theory (EFT) methods to nuclear systems provides the opportunity to rigorously estimate the uncertainties originating in the nuclear Hamiltonian. Yet this is just one source of uncertainty in the observables predicted by calculations based on nuclear EFTs. We discuss the goals of uncertainty quantification in such calculations and outline a recipe to obtain statistically meaningful error bars for their predictions. We argue that the differe...

Furnstahl, R. J.; Phillips, D. R.; Wesolowski, S.

2014-01-01

316

Uncertainty Quantification in Hybrid Dynamical Systems

Uncertainty quantification (UQ) techniques are frequently used to ascertain output variability in systems with parametric uncertainty. Traditional algorithms for UQ are either system-agnostic and slow (such as Monte Carlo) or fast with stringent assumptions on smoothness (such as polynomial chaos and Quasi-Monte Carlo). In this work, we develop a fast UQ approach for hybrid dynamical systems by extending the polynomial chaos methodology to these systems. To capture discontinuities, we use a wavelet-based Wiener-Haar expansion. We develop a boundary layer approach to propagate uncertainty through separable reset conditions. We also introduce a transport theory based approach for propagating uncertainty through hybrid dynamical systems. Here the expansion yields a set of hyperbolic equations that are solved by integrating along characteristics. The solution of the partial differential equation along the characteristics allows one to quantify uncertainty in hybrid or switching dynamical systems. The above method...

Sahai, Tuhin

2011-01-01

317

Finite-size corrections in the SU(2)xSU(2) sector of type IIA string theory on AdS4xCP3

International Nuclear Information System (INIS)

We consider finite-size corrections in the SU(2)xSU(2) sector of type IIA string theory on AdS4xCP3, which is the string dual of the recently constructed N=6 superconformal Chern-Simons theory of Aharony, Bergman, Jafferis and Maldacena (ABJM theory). The string states we consider are in the RxS2xS2 subspace of AdS4xCP3 with an angular momentum J on CP3 being large. We compute the finite-size corrections using two different methods, one is to consider curvature corrections to the Penrose limit giving an expansion in 1/J, the other by considering a low energy expansion in ?'=?/J2 of the string theory sigma-model, ? being the 't Hooft coupling of the dual ABJM theory. For both methods there are interesting issues to deal with. In the near-pp-wave method there is a 1/?(J) interaction term for which we use zeta-function regularization in order to compute the 1/J correction to the energy. For the low energy sigma-model expansion we have to take into account a non-trivial coupling to a non-dynamical transverse direction. We find agreement between the two methods. At order ?' and ?'2, for small ?', our results are analogous to the ones for the SU(2) sector in type IIB string theory on AdS5xS5. Instead at order ?'3 there are interactions between the two two-spheres. We compare our results with the recently proposed all-loop Bethe ansatz of Gromov and Vieira and find agreement

318

Finite-size corrections in the SU(2) x SU(2) sector of type IIA string theory on AdS_4 x CP^3

We consider finite-size corrections in the SU(2) x SU(2) sector of type IIA string theory on AdS_4 x CP^3, which is the string dual of the recently constructed N=6 superconformal Chern-Simons theory of Aharony, Bergman, Jafferis and Maldacena (ABJM theory). The string states we consider are in the R x S^2 x S^2 subspace of AdS_4 x CP^3 with an angular momentum J on CP^3 being large. We compute the finite-size corrections using two different methods, one is to consider curvature corrections to the Penrose limit giving an expansion in 1/J, the other by considering a low energy expansion in lambda'=lambda/J^2 of the string theory sigma-model, lambda being the 't Hooft coupling of the dual ABJM theory. For both methods there are interesting issues to deal with. In the near-pp-wave method there is a 1/\\sqrt{J} interaction term for which we use zeta-function regularization in order to compute the 1/J correction to the energy. For the low energy sigma-model expansion we have to take into account a non-trivial coupli...

Astolfi, Davide; Grignani, Gianluca; Harmark, Troels; Orselli, Marta

2008-01-01

319

Digital Repository Infrastructure Vision for European Research (DRIVER)

Background and Aim: Many studies show that the only way to control diabetes and prevent its debilitating complications is continuous self-care. This study aimed to determine factors affecting self-care behavior of diabetic women in Khoy City, Iran based the extended theory of reasoned action (ETRA). Materials and Methods: A sample of 352 women with type 2 diabetes referring to a Diabetes Clinic in Khoy City in West Azarbaijan Province, Iran participated in the study. Appropriate instruments w...

Ebrahim Hajizadeh; Shamseddin Niknami; Hasan Eftekhar Ardebili; Davood Shojaeizadeh; Mohammad Alizadeh; Alireza Didarloo

2011-01-01

320

International Nuclear Information System (INIS)

An homogeneous model which simulates the stationary behavior of steam generators of PWR type reactors and uses the differential formalism of perturbation theory for analysing sensibility of linear and non-linear responses, is presented. The PERGEVAP computer code to calculate the temperature distribution in the steam generator and associated importance function, is developed. The code also evaluates effects of the thermohydraulic parameter variation on selected functionals. The obtained results are compared with results obtained by GEVAP computer code . (M.C.K.)

321

Training load quantification in triathlon

Directory of Open Access Journals (Sweden)

Full Text Available There are different Indices of Training Stress of varying complexity, to quantification Training load. Examples include the training impulse (TRIMP, the session (RPE, Lucia’s TRIMP or Summated Zone Score. But the triathlon, a sport to be combined where there are interactions between different segments, is a complication when it comes to quantify the training. The aim of this paper is to review current methods of quantification, and to propose a scale to quantify the training load in triathlon simple application.

ROBERTO CEJUELA ANTA

2011-06-01

322

Digital Repository Infrastructure Vision for European Research (DRIVER)

Hurwitz numbers are the Laurent coefficients of an elliptic function $\\wp(u)$ of cyclotomic type, and they are natural generalization of the Bernoulli numbers. This paper gives new generalization of Bernoulli and Hurwitz numbers for higher genus cases. They satisfy completely von Staudt-Clausen type theorem, an extension of von Staudt second theorem, and Kummer type congruence relation. The present paper is revised and combined version of math.NT/0304377 and math.NT/0312178 ...

O?nishi, Yoshihiro

2004-01-01

323

Virus detection and quantification using electrical parameters

Here we identify and quantitate two similar viruses, human and feline immunodeficiency viruses (HIV and FIV), suspended in a liquid medium without labeling, using a semiconductor technique. The virus count was estimated by calculating the impurities inside a defined volume by observing the change in electrical parameters. Empirically, the virus count was similar to the absolute value of the ratio of the change of the virus suspension dopant concentration relative to the mock dopant over the change in virus suspension Debye volume relative to mock Debye volume. The virus type was identified by constructing a concentration-mobility relationship which is unique for each kind of virus, allowing for a fast (within minutes) and label-free virus quantification and identification. For validation, the HIV and FIV virus preparations were further quantified by a biochemical technique and the results obtained by both approaches corroborated well. We further demonstrate that the electrical technique could be applied to accurately measure and characterize silica nanoparticles that resemble the virus particles in size. Based on these results, we anticipate our present approach to be a starting point towards establishing the foundation for label-free electrical-based identification and quantification of an unlimited number of viruses and other nano-sized particles.

Ahmad, Mahmoud Al; Mustafa, Farah; Ali, Lizna M.; Rizvi, Tahir A.

2014-10-01

324

Virus detection and quantification using electrical parameters.

Here we identify and quantitate two similar viruses, human and feline immunodeficiency viruses (HIV and FIV), suspended in a liquid medium without labeling, using a semiconductor technique. The virus count was estimated by calculating the impurities inside a defined volume by observing the change in electrical parameters. Empirically, the virus count was similar to the absolute value of the ratio of the change of the virus suspension dopant concentration relative to the mock dopant over the change in virus suspension Debye volume relative to mock Debye volume. The virus type was identified by constructing a concentration-mobility relationship which is unique for each kind of virus, allowing for a fast (within minutes) and label-free virus quantification and identification. For validation, the HIV and FIV virus preparations were further quantified by a biochemical technique and the results obtained by both approaches corroborated well. We further demonstrate that the electrical technique could be applied to accurately measure and characterize silica nanoparticles that resemble the virus particles in size. Based on these results, we anticipate our present approach to be a starting point towards establishing the foundation for label-free electrical-based identification and quantification of an unlimited number of viruses and other nano-sized particles. PMID:25355078

Ahmad, Mahmoud Al; Mustafa, Farah; Ali, Lizna M; Rizvi, Tahir A

2014-01-01

325

International Nuclear Information System (INIS)

After noting some advantages of using perturbation theory some of the various types are related on a chart and described, including many-body nonlinear summations, quartic force-field fit for geometry, fourth-order correlation approximations, and a survey of some recent work. Alternative initial approximations in perturbation theory are also discussed. 25 references

326

Digital Repository Infrastructure Vision for European Research (DRIVER)

Objectives To investigate effects of endurance, functional and strength training on subjective vitality in older adults. Using the self-determination theory (SDT) framework we tested the moderating effects of autonomy support and mediating effects of need satisfaction on participants’ changes in vitality. Design Parallel-groups randomized controlled trial. Methods 138 older adults (M = 74.2 years, SD = 4.5) were randomized to a training group or wait-list control, with assessments at base...

Solberg, Paul Andre; Hopkins, Will; Ommundsen, Yngvar; Halvari, Hallgeir

2012-01-01

327

DEFF Research Database (Denmark)

Time-dependent scattering theory for a large class of translation invariant models, including the Nelson and Polaron models, restricted to the vacuum and one-particle sectors is studied. Asymptotic completeness of these Hamiltonians is shown. The translation invariance imply that the Hamiltonian is fibered with respect to the total momentum. On the way to asymptotic completeness we determine the spectral structure of the fiber Hamiltonians, establish a Mourre estimate and derive a geometric asymptotic completeness statement as an intermediate step.

Gérard, Christian; MØller, Jacob Schach

2010-01-01

328

This monograph offers a state-of-the-art mathematical account of functional integration methods in the context of self-adjoint operators and semigroups using the concepts and tools of modern stochastic analysis. These ideas are then applied principally to a rigorous treatment of some fundamental models of quantum field theory. In this self-contained presentation of the material both beginners and experts are addressed, while putting emphasis on the interdisciplinary character of the subject.

Lörinczi, József; Betz, Volker

2011-01-01

329

Hawking radiation of black holes in non-minimal R ? F 2-type coupled Einstein-Maxwell theory

We investigate the Hawking radiation and greybody factor for a scalar field on the background of the black holes in the theory of the non-minimal R ? F 2-coupled electromagnetic fields to gravity. For different asymptotic structures caused by the real power number ?, we find that the influences of the real power number on the Hawking radiation and greybody factor are different. We also show that the different coupling constant also affects the Hawking radiation and greybody factor.

Liu, Yan; Jing, Jiliang

2012-07-01

330

International Nuclear Information System (INIS)

Simple tangent, hard site chains near a hard wall are modeled with a density functional (DF) theory that uses the direct correlation function, c(r), as its ''input.'' Two aspects of this DF theory are focused upon: (1) the consequences of variations in c(r)'s detailed form; and (2) the correct way to introduce c(r) into the DF formalism. The most important aspect of c(r) is found to be its integrated value, c(0). Indeed, it appears that, for fixed c(0), all reasonable guesses of the detailed shape of c(r) result in surprisingly similar density distributions, ?(r). Of course, the more accurate the c(r), the better the ?(r). As long as the length scale introduced by c(r) is roughly the hard site diameter and as long as the solution remains liquid-like, the ?(r) is found to be in good agreement with simulation results. The c(r) is used in DF theory to calculate the medium-induced potential, UM(r), from the density distribution, ?(r). The form of UM(r) can be chosen to be one of a number of different forms. It is found that the forms for UM(r)which yield the most accurate results for the wall problem are also those which were suggested as accurate in previous, related studies. (c) 2000 American Institute of Physics

331

Direct qPCR quantification of unprocessed forensic casework samples.

The current short tandem repeat (STR) typing workflow for forensic casework samples involves sample collection, sample screening, DNA extraction, DNA qPCR quantification and STR amplification. Although very effective and powerful, this workflow still has room for improvements. For example, the screening assays in practice do not provide DNA related information and also do not work with touch DNA samples, which make up of the majority of the property crime samples. It is known that not all DNA samples have equal probative values. Considering the DNA backlog situation crime laboratories face today, an effective screening tool would be highly desirable. It would allow forensic scientists to prioritize the DNA samples so that the limited resources would be first spent on samples that would have better chances of producing informative STR profiles. qPCR assay does provide DNA quantity and gender information and would be an ideal screening tool. However, prior to quantification, sample extraction and purification are required. By the time a DNA sample is ready for qPCR quantification, time and resources have already been spent on samples that should have been given low priority or excluded from further processing if DNA quantity and gender information were known. To overcome this problem, a direct quantification technology is developed to allow qPCR quantification of casework samples without the need for DNA extraction and purification. The key to a direct qPCR assay is the PE-Swab, a novel sample collection device. A small sample punch can be generated from a PE-Swab and placed in a qPCR reaction for quantification. After optimizing the punch size and the quantification software baseline setting, accurate DNA quantification can be obtained from a sample without the need to carry out DNA extraction and purification. Proof of concept studies were done with low lever touch samples as well as blood samples. The PE-Swab also allows direct STR amplification of casework samples without the need for DNA extraction. Besides its potential as a screening tool, the direct qPCR assay can also be used to normalize the DNA input for a direct STR amplification reaction. The feasibility of the direct qPCR/direct STR amplification workflow was demonstrated with touch DNA samples and blood stain samples. PMID:24705062

Liu, Jason Yingjie

2014-07-01

332

Energy Technology Data Exchange (ETDEWEB)

Simple tangent, hard site chains near a hard wall are modeled with a Density Functional (DF) theory that uses the direct correlation function, c(r), as its ''input''. Two aspects of this DF theory are focused upon: (1) the consequences of variations in c(r)'s detailed form; and (2) the correct way to introduce c(r) into the DF formalism. The most important aspect of c(r) is found to be its integrated value, {cflx c}(0). Indeed, it appears that, for fixed {cflx c}(0), all reasonable guesses of the detailed shape of c(r) result in surprisingly similar density distributions, {rho}(r). Of course, the more accurate the c(r), the better the {rho}(r). As long as the length scale introduced by c(r) is roughly the hard site diameter and as long as the solution remains liquid-like, the {rho}(r) is found to be in good agreement with simulation results. The c(r) is used in DF theory to calculate the medium-induced-potential, U{sub M}(r) from the density distribution, {rho}(r). The form of U{sub M}(r) can be chosen to be one of a number of different forms. It is found that the forms for U{sub M}(r), which yield the most accurate results for the wall problem, are also those which were suggested as accurate in previous, related studies.

CURRO,JOHN G.; HOOPER,JUSTIN B.; MCCOY,JOHN D.; PILEGGI, MORGAN T.; WEINHOLD,JEFFREY D.

1999-10-28

333

The Types of Axisymmetric Exact Solutions Closely Related to n-SOLITONS for Yang-Mills Theory

In this letter, we point out that if a symmetric 2×2 real matrix M(?,z) obeys the Belinsky-Zakharov equation and |det(M)|=1, then an axisymmetric Bogomol'nyi field exact solution for the Yang-Mills-Higgs theory can be given. By using the inverse scattering technique, some special Bogomol'nyi field exact solutions, which are closely related to the true solitons, are generated. In particular, the Schwarzschild-like solution is a two-soliton-like solution.

Zhong, Zai Zhe

334

Automated quantification and analysis of mandibular asymmetry

DEFF Research Database (Denmark)

We present an automated method of spatially detailed 3D asymmetry quantification in mandibles extracted from CT and apply it to a population of infants with unilateral coronal synostosis (UCS). An atlas-based method employing non-rigid registration of surfaces is used for determining deformation fields, thereby establishing detailed anatomical point correspondence between subjects as well as between points on the left and right side of the mid-sagittal plane (MSP). Asymmetry is defined in terms of the vector between a point and the corresponding anatomical point on the opposite side of the MSP after mirroring the mandible across the MSP. A principal components analysis of asymmetry characterizes the major types of asymmetry in the population, and successfully separates the asymmetric UCS mandibles from a number of less asymmetric mandibles from a control population.

Ólafsdóttir, Hildur

2010-01-01

335

An uncertainty inventory demonstration - a primary step in uncertainty quantification

Energy Technology Data Exchange (ETDEWEB)

Tools, methods, and theories for assessing and quantifying uncertainties vary by application. Uncertainty quantification tasks have unique desiderata and circumstances. To realistically assess uncertainty requires the engineer/scientist to specify mathematical models, the physical phenomena of interest, and the theory or framework for assessments. For example, Probabilistic Risk Assessment (PRA) specifically identifies uncertainties using probability theory, and therefore, PRA's lack formal procedures for quantifying uncertainties that are not probabilistic. The Phenomena Identification and Ranking Technique (PIRT) proceeds by ranking phenomena using scoring criteria that results in linguistic descriptors, such as importance ranked with words, 'High/Medium/Low.' The use of words allows PIRT to be flexible, but the analysis may then be difficult to combine with other uncertainty theories. We propose that a necessary step for the development of a procedure or protocol for uncertainty quantification (UQ) is the application of an Uncertainty Inventory. An Uncertainty Inventory should be considered and performed in the earliest stages of UQ.

Langenbrunner, James R. [Los Alamos National Laboratory; Booker, Jane M [Los Alamos National Laboratory; Hemez, Francois M [Los Alamos National Laboratory; Salazar, Issac F [Los Alamos National Laboratory; Ross, Timothy J [UNM

2009-01-01

336

Quantification of mannan-binding lectin

DEFF Research Database (Denmark)

Mannan-binding lectin (MBL) is attracting considerable interest due to its role in the immune defense. The high frequency of congenital MBL deficiency makes it feasible to evaluate clinical relevance through epidemiological investigations on fairly limited numbers of patients. MBL deficiency is determined by three mutant allotypes termed B, C and D in the coding region as well as mutations in the promoter region. It has been suggested that individuals, with deficiency-associated allotypes, may present significant amounts of low molecular weight MBL. We have compared the quantification of MBL by four commercially available assays with results obtained by our own in-house assays. Most assays are selectively sensitive for the wild type MBL (allotype A), but special combinations of antibodies also detect mutant forms of MBL. Thus a sandwich-type time-resolved immunoflourometric assay (TRIFMA), with a mouse monoclonal antibody (93C) as the catching and detecting antibody, shows B/B and D/D homozygous individuals to present signals corresponding to up to 500 ng MBL per ml (with plasma from an A/A individual as standard) as compared to less than 50 ng/ml and 200 ng/ml, respectively, when measured in other assays. In GPC at isotonic conditions the MBL in B/B and D/D individuals showed a Mr of 450 kDa. This MBL cannot bind to mannan. We further present a new method for quantifying the amount of MBL polypeptide chain. By applying plasma samples on SDS-PAGE at reducing conditions followed by Western blotting and quantification by chemiluminescense, this approach presents single polypeptide chains to the antibody independent of allotype differences in the collagen-like region. Titrations of recombinant MBL served as standard. In sera from homozygous mutants (O/O) the MBL concentrations estimated on Western blot were in the range of 100 to 500 ng/ml and correlated with that measured in the 93C-based TRIFMA.

Frederiksen, Pernille D; Thiel, Steffen

2006-01-01

337

Energy Technology Data Exchange (ETDEWEB)

The string one-loop computation of the Fayet–Iliopoulos D-term in type I string theory in the case of T{sup 6}/Z{sub 3} orbifold compactification associated with annulus (planar) and the Möbius strip string worldsheet diagrams is reexamined. The mass extracted from the sum of these amplitudes through a limiting procedure is found to be non-vanishing, which is contrary to the earlier computation. The sum can be made finite by a rescaling of the modular parameter in the closed string channel.

Itoyama, H., E-mail: itoyama@sci.osaka-cu.ac.jp [Department of Mathematics and Physics, Graduate School of Science, Osaka City University (Japan); Osaka City University Advanced Mathematical Institute (OCAMI), 3-3-138, Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan); Yano, Kohei, E-mail: kyano@sci.osaka-cu.ac.jp [Department of Mathematics and Physics, Graduate School of Science, Osaka City University (Japan)

2013-12-18

338

Object Oriented Design Security Quantification

Digital Repository Infrastructure Vision for European Research (DRIVER)

Quantification of security at early phase produces a significant improvement to understand the management of security artifacts for best possible results. The proposed study discusses a systematic approach to quantify security based on complexity factors which having impact on security attributes. This paper provides a road-map to researchers and software practitioner to assess, and preferably, quantify software security in design phase. A security assessment through complexity framework (SVD...

Suhel Ahmad Khan

2011-01-01

339

Analysis of New Type Air-conditioning for Loom Based on CFD Simulation and Theory of Statistics

Directory of Open Access Journals (Sweden)

Full Text Available Based on theory of statistics, main factors affecting effects of loom workshop’s large and small zone ventilation using the CFD simulation in this paper. Firstly, four factors and three levels of orthogonal experimental table is applied to CFD simulation, the order from major to minor of four factors is obtained, which can provide theoretical basis for design and operation. Then single-factor experiment method is applied to CFD simulation, certain factor changing can be obtained with best levels of other factors. Base on above recommend parameters, CFD software is applied to simulate relative humid and PMV on the loom. Lastly, comparison of simulation results and experiment is used to verify feasibility of simulation results.

Ruiliang Yang

2011-01-01

340

International Nuclear Information System (INIS)

Frequency conversion (FC) and type-II parametric down-conversion (PDC) processes serve as basic building blocks for the implementation of quantum optical experiments: type-II PDC enables the efficient creation of quantum states such as photon-number states and Einstein–Podolsky–Rosen (EPR)-states. FC gives rise to technologies enabling efficient atom–photon coupling, ultrafast pulse gates and enhanced detection schemes. However, despite their widespread deployment, their theoretical treatment remains challenging. Especially the multi-photon components in the high-gain regime as well as the explicit time-dependence of the involved Hamiltonians hamper an efficient theoretical description of these nonlinear optical processes. In this paper, we investigate these effects and put forward two models that enable a full description of FC and type-II PDC in the high-gain regime. We present a rigorous numerical model relying on the solution of coupled integro-differential equations that covers the complete dynamics of the process. As an alternative, we develop a simplified model that, at the expense of neglecting time-ordering effects, enables an analytical solution. While the simplified model approximates the correct solution with high fidelity in a broad parameter range, sufficient for many experimental situations, such as FC with low efficiency, entangled photon-pair generation and the heralding of single photons from type-II PDC, our investigations reveal that the rigo investigations reveal that the rigorous model predicts a decreased performance for FC processes in quantum pulse gate applications and an enhanced EPR-state generation rate during type-II PDC, when EPR squeezing values above 12 dB are considered. (paper)

341

Several recent studies suggest that peripheral corticotropin-releasing factor (CRF) receptor type 1 (CRF1) and CRF2 have a counter regulatory action on gastrointestinal functions. We hypothesized that the activity balance of each CRF subtype signaling may determine the changes in colonic motility and visceral sensation. Colonic contractions were assessed by the perfused manometry, and contractions of colonic muscle strips were measured in vitro in rats. Visceromotor response was determined by measuring contractions of abdominal muscle in response to colorectal distensions (CRDs) (60 mm Hg for 10 min twice with a 30-min rest). All drugs were administered through ip route in in vivo studies. CRF increased colonic contractions. Pretreatment with astressin, a nonselective CRF antagonist, blocked the CRF-induced response, but astressin2-B, a selective CRF2 antagonist, enhanced the response by CRF. Cortagine, a selective CRF1 agonist, increased colonic contractions. In in vitro study, CRF increased contractions of muscle strips. Urocortin 2, a selective CRF2 agonist, itself did not alter the contractions but blocked this increased response by CRF. Visceromotor response to the second CRD was significantly higher than that of the first. Astressin blocked this CRD-induced sensitization, but astressin2-B or CRF did not affect it. Meanwhile, astressin2-B together with CRF significantly enhanced the sensitization. Urocortin 2 blocked, but cortagine significantly enhanced, the sensitization. These results indicated that peripheral CRF1 signaling enhanced colonic contractility and induced visceral sensitization, and these responses were modulated by peripheral CRF2 signaling. The activity balance of each subtype signaling may determine the colonic functions in response to stress. PMID:25279793

Nozu, Tsukasa; Takakusaki, Kaoru; Okumura, Toshikatsu

2014-12-01

342

International Nuclear Information System (INIS)

The potential distribution in cyclotron-type gaps with liner (outer electrodes at ground potential) is determined via Schwarz-Christoffel transformation as well as by computer analysis (relaxation method). First-order focusing formulas for both static as well as time-varying potentials are derived. In addition exact calculations were carried out by direct numerical integration of the equations of motion with a computer program. The numerical data permitted an accurate evaluation of the validity of the analytical approximation as well as further improvement of the theoretical formulas. Focusing relations are presented in a generalized form which shows the scaling laws and is readily applicable to different types of particles, energies or lens geometries. As an example, the theory is applied in the axial motion of ions in a cyclotron

343

Probability theory governs the outcome of a game; there is a distribution over mixed strat.'s, not a single "equilibrium". To predict a single mixed strategy must use our loss function (external to the game's players. Provides a quantification of any strategy's rationality. Prove rationality falls as cost of computation rises (for players who have not previously interacted). All extends to games with varying numbers of players.

Wolpert, David H.

2005-01-01

344

Motivated by studies on 4d black holes and q-deformed 2d Yang Mills theory, and borrowing ideas from compact geometry of the blowing up of affine ADE singularities, we build a class of local Calabi-Yau threefolds (CY^{3}) extending the local 2-torus model \\mathcal{O}(m)\\oplus \\mathcal{O}(-m)\\to T^{2\\text{}} considered in hep-th/0406058 to test OSV conjecture. We first study toric realizations of T^{2} and then build a toric representation of X_{3} using intersections of local Calabi-Yau threefolds \\mathcal{O}(m)\\oplus \\mathcal{O}(-m-2)\\to \\mathbb{P}^{1}. We develop the 2d \\mathcal{N}=2 linear \\sigma-model for this class of toric CY^{3}s. Then we use these local backgrounds to study partition function of 4d black holes in type IIA string theory and the underlying q-deformed 2d quiver gauge theories. We also make comments on 4d black holes obtained from D-branes wrapping cycles in \\mathcal{O}(\\mathbf{m}) \\oplus \\mathcal{O}(\\mathbf{-m-2}%) \\to \\mathcal{B}_{k} with \\mathbf{m=}(m_{1},...,m_{k}) a k-dim integer vec...

Laamara, R A; Drissi, L B; Saidi, E H

2006-01-01

345

Critical evaluation of HPV16 gene copy number quantification by SYBR green PCR

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Human papilloma virus (HPV) load and physical status are considered useful parameters for clinical evaluation of cervical squamous cell neoplasia. However, the errors implicit in HPV gene quantification by PCR are not well documented. We have undertaken the first rigorous evaluation of the errors that can be expected when using SYBR green qPCR for quantification of HPV type 16 gene copy numbers. We assessed a modified method, in which external calibration ...

Pett Mark R; Herdman Michael T; Stanley Margaret; Foster Nicola; Ng Grace; Roberts Ian; Teschendorff Andrew; Coleman Nicholas

2008-01-01

346

Critical evaluation of HPV16 gene copy number quantification by SYBR green PCR

Digital Repository Infrastructure Vision for European Research (DRIVER)

Background: Human papilloma virus (HPV) load and physical status are considered useful parameters for clinical evaluation of cervical squamous cell neoplasia. However, the errors implicit in HPV gene quantification by PCR are not well documented. We have undertaken the first rigorous evaluation of the errors that can be expected when using SYBR green qPCR for quantification of HPV type 16 gene copy numbers. We assessed a modified method, in which external calibration curves were generated fro...

2008-01-01

347

LRS Bianchi type I universes exhibiting Noether symmetry in the scalar-tensor Brans-Dicke theory

Digital Repository Infrastructure Vision for European Research (DRIVER)

Following up on hints of anisotropy in the cosmic microwave background radiation (CMB) data, we investigate locally rotational symmetric (LRS) Bianchi type I spacetimes with non-minimally coupled scalar fields. To single out potentially more interesting solutions, we search for Noether symmetry in this system. We then specialize to the Brans-Dicke (BD) field in such a way that the Lagrangian becomes degenerate (nontrivial) and solve the equations for Noether symmetry and the...

Kucukakca, Y.; Camci, U.; Semiz, I?

2012-01-01

348

Directory of Open Access Journals (Sweden)

Full Text Available The damage caused by corrosion in chemical process installations can lead to unexpected plant shutdowns and the leakage of potentially toxic chemicals into the environment. When subjected to corrosion, structural changes in the material occur, leading to energy releases as acoustic waves. This acoustic activity can in turn be used for corrosion monitoring, and even for predicting the type of corrosion. Here we apply wavelet packet decomposition to extract features from acoustic emission signals. We then use the extracted wavelet packet coefficients for distinguishing between the most important types of corrosion processes in the chemical process industry: uniform corrosion, pitting and stress corrosion cracking. The local discriminant basis selection algorithm can be considered as a standard for the selection of the most discriminative wavelet coefficients. However, it does not take the statistical dependencies between wavelet coefficients into account. We show that, when these dependencies are ignored, a lower accuracy is obtained in predicting the corrosion type. We compare several mutual information filters to take these dependencies into account in order to arrive at a more accurate prediction.

Marc M. Van Hulle

2011-05-01

349

The damage caused by corrosion in chemical process installations can lead to unexpected plant shutdowns and the leakage of potentially toxic chemicals into the environment. When subjected to corrosion, structural changes in the material occur, leading to energy releases as acoustic waves. This acoustic activity can in turn be used for corrosion monitoring, and even for predicting the type of corrosion. Here we apply wavelet packet decomposition to extract features from acoustic emission signals. We then use the extracted wavelet packet coefficients for distinguishing between the most important types of corrosion processes in the chemical process industry: uniform corrosion, pitting and stress corrosion cracking. The local discriminant basis selection algorithm can be considered as a standard for the selection of the most discriminative wavelet coefficients. However, it does not take the statistical dependencies between wavelet coefficients into account. We show that, when these dependencies are ignored, a lower accuracy is obtained in predicting the corrosion type. We compare several mutual information filters to take these dependencies into account in order to arrive at a more accurate prediction. PMID:22163921

Van Dijck, Gert; Van Hulle, Marc M.

2011-01-01

350

We formulate a unified framework of balance laws and thermodynamically-consistent constitutive equations which couple Cahn-Hilliard-type species diffusion with large elastic deformations of a body. The traditional Cahn-Hilliard theory, which is based on the species concentration c and its spatial gradient ?c, leads to a partial differential equation for the concentration which involves fourth-order spatial derivatives in c; this necessitates use of basis functions in finite-element solution procedures that are piecewise smooth and globally C1-continuous. In order to use standard C0-continuous finite-elements to implement our phase-field model, we use a split-method to reduce the fourth-order equation into two second-order partial differential equations (pdes). These two pdes, when taken together with the pde representing the balance of forces, represent the three governing pdes for chemo-mechanically coupled problems. These are amenable to finite-element solution methods which employ standard C0-continuous finite-element basis functions. We have numerically implemented our theory by writing a user-element subroutine for the widely used finite-element program Abaqus/Standard. We use this numerically implemented theory to first study the diffusion-only problem of spinodal decomposition in the absence of any mechanical deformation. Next, we use our fully coupled theory and numerical-implementation to study the combined effects of diffusion and stress on the lithiation of a representative spheroidal-shaped particle of a phase-separating electrode material.

Di Leo, Claudio V.; Rejovitzky, Elisha; Anand, Lallit

2014-10-01

351

A semantic analysis of quantification in English

Digital Repository Infrastructure Vision for European Research (DRIVER)

Throughout early English grammars and the following linguistic literature of the 20th century, the class of quantifiers has faced an identity crisis, brought about most strongly by purely or strongly syntax-based analyses and the lack of a comprehensive account of the semantic behavior of quantification. This analysis examines quantificational behavior from a wholly semantic view and distinguishes the necessary and sufficient parameters for describing quantification and delineating its subcla...

Vandiver, Whitney R.

2011-01-01

352

The electronic conductivity and thermodynamic stability of mixed n-type and p-type doped SrTiO3 have been investigated at anodic solid oxide fuel cell (SOFC) conditions using density functional theory (DFT) calculations. In particular, constrained ab initio thermodynamic calculations have been performed to evaluate the phase stability and reducibility of various Nb- and Ga-doped SrTiO3 at synthesized and anodic SOFC conditions. The density of states (DOS) of these materials was analyzed to study the effects of n- and p-doping on the electronic conductivity. In agreement with experimental observations, we find that the transformation from 20% Nb-doped Sr-deficient SrTiO3 to a non-Sr-deficient phase occurs at high temperature and low oxygen partial pressure, which leads to a significant improvement in electronic conductivity. A mixed ionic/electronic conductor is obtained when doping 20% Nb-doped SrTiO3 with small amounts of Ga (10%) in a reducing environment and high temperature. Doping with higher concentrations of Ga, e.g., 20%, diminishes the electronic conductivity of the material. These findings suggest that independent of the specific dopant, mixed ionic/electronic conductivity can be obtained in perovskite oxides under reducing conditions and high temperatures by doping the B-site with small amounts of both n-type and p-type dopants.

Suthirakun, Suwit; Ammal, Salai Cheettu; Xiao, Guoliang; Chen, Fanglin; Zur Loye, Hans-Conrad; Heyden, Andreas

2011-11-01

353

Energy Technology Data Exchange (ETDEWEB)

The initial reaction mechanism of atomic layer deposited TiO{sub 2} thin film on the silicon surface using Cp*Ti(OCH{sub 3}){sub 3} as the metal precursor has been investigated by using the density functional theory. We find that Cp*Ti(OCH{sub 3}){sub 3} adsorbed state can be formed via the hydrogen bonding interaction between CH{sub 3}O ligands and the Si-OH sites, which is in good agreement with the quadrupole mass spectrometry (QMS) experimental observations. Moreover, the desorption of adsorbed Cp*Ti(OCH{sub 3}){sub 3} is favored in the thermodynamic equilibrium state. The elimination reaction of CH{sub 3}OH can occur more readily than that of Cp*H during the Cp*Ti(OCH{sub 3}){sub 3} pulse. This conclusion is also confirmed by the QMS experimental results. - Highlights: Black-Right-Pointing-Pointer Initial reaction mechanism of atomic layer deposition of TiO{sub 2} has been studied. Black-Right-Pointing-Pointer The Cp*Ti(OCH{sub 3}){sub 3} absorbed state on silicon surface is formed by hydrogen bonds. Black-Right-Pointing-Pointer The elimination of CH{sub 3}OH occurs more readily than that of Cp*H in Cp*Ti(OCH{sub 3}){sub 3}. Black-Right-Pointing-Pointer The Cp*Ti(OCH{sub 3}){sub 3} adsorbs on silicon surface via the CH{sub 3}O ligand.

Zhou, Guangfen [College of Science, Beijing Institute of Technology, Beijing 100081 (China); College of Science, Hebei University of Science and Technology, Shijiazhuang 050018 (China); Ren, Jie, E-mail: renjie@fudan.edu.cn [College of Science, Hebei University of Science and Technology, Shijiazhuang 050018 (China); Zhang, Shaowen [College of Science, Beijing Institute of Technology, Beijing 100081 (China)

2012-12-01

354

Quantification of Information in a One-Way Plant-to-Animal Communication System

Directory of Open Access Journals (Sweden)

Full Text Available In order to demonstrate possible broader applications of information theory to the quantification of non-human communication systems, we apply calculations of information entropy to a simple chemical communication from the cotton plant (Gossypium hirsutum to the wasp (Cardiochiles nigriceps studied by DeMoraes et al. The purpose of this chemical communication from cotton plants to wasps is presumed to be to allow the predatory wasp to more easily obtain the location of its preferred prey—one of two types of parasitic herbivores feeding on the cotton plants. Specification of the plant-eating herbivore feeding on it by the cotton plants allows preferential attraction of the wasps to those individual plants. We interpret the emission of nine chemicals by the plants as individual signal differences, (depending on the herbivore type, to be detected by the wasps as constituting a nine-signal one-way communication system across kingdoms (from the kingdom Plantae to the kingdom Animalia. We use fractional differences in the chemical abundances, (emitted as a result of the two herbivore types, to calculate the Shannon information entropic measures (marginal, joint, and mutual entropies, as well as the ambiguity, etc. of the transmitted message. We then compare these results with the subsequent behavior of the wasps, (calculating the equivocation in the message reception, for possible insights into the history and actual working of this one-way communication system.

Laurance R. Doyle

2009-08-01

355

International Nuclear Information System (INIS)

The effect of anisotropy on the measurement, by muon spin rotation, of the London penetration depth in the high Tc uniaxial type II superconductors is considered in detail. Expressions are derived which will allow the principal penetration depths, ?1 and ?2, to be determined using measurements of the ?SR line width from single crystals. For polycrystalline, powder or sintered, samples an expression is derived which will allow an effective penetration depth, ?eff, to be determined from the measured ?SR line width. Further, it is shown that for all anisotropy ratios, ?2/?1, greater than five ?1 ? 0.81?eff. (author)

356

International Nuclear Information System (INIS)

The depressurization behaviour of a fibre-type thermal insulation has been investigated both by measurements with air and helium and with numerical models. A simple lumped parameter model has been used to reproduce the measured transients for air as well as for helium. All the experimental data have been obtained with reasonable accuracy by fitting two empirical parameters, the effective surfaces of the flow through the venting holes and the flow through the perforated tube. It is remarkable that the same parameters reproduce the experimental data for such different gases as air and helium. The dependence of the depressurization behaviour on the different parameters has been treated by a dimensional analysis. (Auth.)

357

International Nuclear Information System (INIS)

We study the probability distribution P(?) of the cosmological constant ? in a specific set of KKLT type models of supersymmetric IIB vacua. We show that, as we sweep through the quantized flux values in this flux compactification, P(?) behaves divergent at ?=0? and the median magnitude of ? drops exponentially as the number of complex structure moduli h2,1 increases. Also, owing to the hierarchical and approximate no-scale structure, the probability of having a positive Hessian (mass-squared matrix) approaches unity as h2,1 increases

358

An EPGPT-based approach for uncertainty quantification

International Nuclear Information System (INIS)

Generalized Perturbation Theory (GPT) has been widely used by many scientific disciplines to perform sensitivity analysis and uncertainty quantification. This manuscript employs recent developments in GPT theory, collectively referred to as Exact-to-Precision Generalized Perturbation Theory (EPGPT), to enable uncertainty quantification for computationally challenging models, e.g. nonlinear models associated with many input parameters and many output responses and with general non-Gaussian parameters distributions. The core difference between EPGPT and existing GPT is in the way the problem is formulated. GPT formulates an adjoint problem that is dependent on the response of interest. It tries to capture via the adjoint solution the relationship between the response of interest and the constraints on the state variations. EPGPT recasts the problem in terms of a smaller set of what is referred to as the 'active' responses which are solely dependent on the physics model and the boundary and initial conditions rather than on the responses of interest. The objective of this work is to apply an EPGPT methodology to propagate cross-sections variations in typical reactor design calculations. The goal is to illustrate its use and the associated impact for situations where the typical Gaussian assumption for parameters uncertainties is not valid and when nonlinear behavior must be considered. To allow this demonstration, exaggerated variations will be employed to stimulate nonlinear behavior in simple prototypical neutronics models. (authors)

359

Object Oriented Design Security Quantification

Directory of Open Access Journals (Sweden)

Full Text Available Quantification of security at early phase produces a significant improvement to understand the management of security artifacts for best possible results. The proposed study discusses a systematic approach to quantify security based on complexity factors which having impact on security attributes. This paper provides a road-map to researchers and software practitioner to assess, and preferably, quantify software security in design phase. A security assessment through complexity framework (SVDF has been proposed in order to incorporate security to develop quality products. It may be used to benchmark software products according to their severity.

Suhel Ahmad Khan

2011-05-01

360

LRS Bianchi type I universes exhibiting Noether symmetry in the scalar-tensor Brans-Dicke theory

Following up on hints of anisotropy in the cosmic microwave background radiation (CMB) data, we investigate locally rotational symmetric (LRS) Bianchi type I spacetimes with non-minimally coupled scalar fields. To single out potentially more interesting solutions, we search for Noether symmetry in this system. We then specialize to the Brans-Dicke (BD) field in such a way that the Lagrangian becomes degenerate (nontrivial) and solve the equations for Noether symmetry and the potential that allows it. Then we find the exact solutions of the equations of motion in terms of three parameters and an arbitrary function. We illustrate with families of examples designed to be generalizations of the well-known power-expansion, exponential expansion and Big Rip models in the Friedmann-Robertson-Walker (FRW) framework. The solutions display surprising variation, a large subset of which features late-time acceleration as is usually ascribed to dark energy (phantom or quintensence), and is consistent with observational da...

Kucukakca, Y; Semiz, ?

2012-01-01

361

LRS Bianchi type I universes exhibiting Noether symmetry in the scalar-tensor Brans-Dicke theory

Following up on hints of anisotropy in the cosmic microwave background radiation data, we investigate locally rotational symmetric Bianchi type I spacetimes with non-minimally coupled scalar fields. To single out potentially more interesting solutions, we search for Noether symmetry in this system. We then specialize to the Brans-Dicke field in such a way that the Lagrangian becomes degenerate (nontrivial) and solve the equations for Noether symmetry and the potential that allows it. Then we find the exact solutions of the equations of motion in terms of three parameters and an arbitrary function. We illustrate with families of examples designed to be generalizations of the well-known power-expansion, exponential expansion and Big Rip models in the Friedmann-Robertson-Walker framework. The solutions display surprising variation, a large subset of which features late-time acceleration as is usually ascribed to dark energy (phantom or quintessence), and is consistent with observational data.

Kucukakca, Y.; Camci, U.; Semiz, ?.

2012-08-01

362

Secret Symmetries of Type IIB Superstring Theory on AdS3 x S3 x M4

We establish features of so-called Yangian secret symmetries for AdS3 type IIB superstring backgrounds thus verifying the persistence of such symmetries to this new instance of the AdS/CFT correspondence. Specifically, we find two different secret symmetry generators which appear unrelated. One generator, anticipated from the previous literature, is more naturally embedded in the algebra governing the integrable scattering problem. The other generator is new and more elusive, and somewhat closer in its form to its higher-dimensional AdS5 counterpart. All of these symmetries respect left-right crossing. In addition, by considering the interplay between left and right representations, we gain a new perspective on the AdS5 case. We also study the RTT-realisation of the Yangian in AdS3 backgrounds thus establishing a new incarnation of the Beisert-de Leeuw construction.

Pittelli, Antonio; Wolf, Martin

2014-01-01

363

Digital Repository Infrastructure Vision for European Research (DRIVER)

The mathematics of classical probability theory was subsumed into classical measure theory by Kolmogorov in 1933. Quantum theory as nonclassical probability theory was incorporated into the beginnings of noncommutative measure theory by von Neumann in the early 1930s, as well. To precisely this end, von Neumann initiated the study of what are now called von Neumann algebras and, with Murray, made a first classification of such algebras into three types. The nonrelativistic quantum theory of s...

Re?dei, Miklo?s; Summers, Stephen Jeffrey

2007-01-01

364

Directory of Open Access Journals (Sweden)

Full Text Available Background: Visceral fat accumulation is associated with the development of metabolic diseases. Anthropometry is one of the methods used to quantify it. aim: to evaluate the relationship between visceral adipose tissue volume (VAT, measured with magnetic resonance imaging (MRI, and anthropometric indexes, such as body mass index (BMI and waist circumference (WC, in type 2 diabetic patients (DM2. Patients and Methods: Twenty four type 2 diabetic patients aged 55 to 78 years (15 females and weighting 61.5 to 97 kg, were included. The patients underwent MRI examination on a Philips Intera® 1.5T MR scanner. The MRI protocol included a spectral excitation sequence centered at the fat peak. The field of view included from L4-L5 to the diaphragmatic border. VAT was measured using the software Image J®. Weight, height, BMI, WC and body fat percentage (BF%, derived from the measurement offour skinfolds with the equation of Durnin and Womersley, were also measured. The association between MRIVAT measurement and anthropometry was evaluated using the Pearson's correlation coefficient. Results: Mean VAT was 2478 ± 758 ml, mean BMI29.5 ± 4.7 kg/m², and mean WC was 100 ± 9.7 cm. There was a poor correlation between VAT, BMI (r = 0.18 and WC (r = 0.56. Conclusions: BMI and WC are inaccurate predictors of VAT volume in type 2 diabetic patients.

Cristóbal Serrano García

2012-12-01

365

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish [...] Abstract in english Background: Visceral fat accumulation is associated with the development of metabolic diseases. Anthropometry is one of the methods used to quantify it. aim: to evaluate the relationship between visceral adipose tissue volume (VAT), measured with magnetic resonance imaging (MRI), and anthropometric [...] indexes, such as body mass index (BMI) and waist circumference (WC), in type 2 diabetic patients (DM2). Patients and Methods: Twenty four type 2 diabetic patients aged 55 to 78 years (15 females) and weighting 61.5 to 97 kg, were included. The patients underwent MRI examination on a Philips Intera® 1.5T MR scanner. The MRI protocol included a spectral excitation sequence centered at the fat peak. The field of view included from L4-L5 to the diaphragmatic border. VAT was measured using the software Image J®. Weight, height, BMI, WC and body fat percentage (BF%), derived from the measurement offour skinfolds with the equation of Durnin and Womersley, were also measured. The association between MRIVAT measurement and anthropometry was evaluated using the Pearson's correlation coefficient. Results: Mean VAT was 2478 ± 758 ml, mean BMI29.5 ± 4.7 kg/m², and mean WC was 100 ± 9.7 cm. There was a poor correlation between VAT, BMI (r = 0.18) and WC (r = 0.56). Conclusions: BMI and WC are inaccurate predictors of VAT volume in type 2 diabetic patients.

Cristóbal, Serrano García; Francisco, Barrera; Pilar, Labbé; Jessica, Liberona; Marco, Arrese; Pablo, Irarrázabal; Cristián, Tejos; Sergio, Uribe.

1535-15-01

366

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish [...] Abstract in english Background: Visceral fat accumulation is associated with the development of metabolic diseases. Anthropometry is one of the methods used to quantify it. aim: to evaluate the relationship between visceral adipose tissue volume (VAT), measured with magnetic resonance imaging (MRI), and anthropometric [...] indexes, such as body mass index (BMI) and waist circumference (WC), in type 2 diabetic patients (DM2). Patients and Methods: Twenty four type 2 diabetic patients aged 55 to 78 years (15 females) and weighting 61.5 to 97 kg, were included. The patients underwent MRI examination on a Philips Intera® 1.5T MR scanner. The MRI protocol included a spectral excitation sequence centered at the fat peak. The field of view included from L4-L5 to the diaphragmatic border. VAT was measured using the software Image J®. Weight, height, BMI, WC and body fat percentage (BF%), derived from the measurement offour skinfolds with the equation of Durnin and Womersley, were also measured. The association between MRIVAT measurement and anthropometry was evaluated using the Pearson's correlation coefficient. Results: Mean VAT was 2478 ± 758 ml, mean BMI29.5 ± 4.7 kg/m², and mean WC was 100 ± 9.7 cm. There was a poor correlation between VAT, BMI (r = 0.18) and WC (r = 0.56). Conclusions: BMI and WC are inaccurate predictors of VAT volume in type 2 diabetic patients.

Cristóbal, Serrano García; Francisco, Barrera; Pilar, Labbé; Jessica, Liberona; Marco, Arrese; Pablo, Irarrázabal; Cristián, Tejos; Sergio, Uribe.

367

International Nuclear Information System (INIS)

Based on first-principles spin-density functional calculations, using the Korringa–Kohn–Rostoker method combined with the coherent potential approximation, we investigated the half-metallic ferromagnetic behavior of (Ga, Fe)N co-doped with carbon within the self-interaction-corrected local density approximation. Mechanism of hybridization and interaction between magnetic ions in p-type (Ga, Fe)N is investigated. Stability energy of ferromagnetic and disorder local moment states was calculated for different carbon concentration. The local density and the self-interaction-corrected approximations have been used to explain the strong ferromagnetic interaction observed and the mechanism that stabilizes this state. The transition temperature to the ferromagnetic state has been calculated within the effective field theory, with a Honmura–Kaneyoshi differential operator technique. - Highlights: ? The paper focus on the study the magnetic properties and electronic structure of p-type (Ga, Fe)N within LDA and SIC approximation. ? These methods allow us to explain the strong ferromagnetic interaction observed and the mechanism for its stability and the mechanism of hybridization and interaction between magnetic ions in p-type (Ga, Fe). ? The results obtained are interesting and can be serve as a reference in the field of dilute magnetic semi conductor.

368

Energy Technology Data Exchange (ETDEWEB)

Based on first-principles spin-density functional calculations, using the Korringa-Kohn-Rostoker method combined with the coherent potential approximation, we investigated the half-metallic ferromagnetic behavior of (Ga, Fe)N co-doped with carbon within the self-interaction-corrected local density approximation. Mechanism of hybridization and interaction between magnetic ions in p-type (Ga, Fe)N is investigated. Stability energy of ferromagnetic and disorder local moment states was calculated for different carbon concentration. The local density and the self-interaction-corrected approximations have been used to explain the strong ferromagnetic interaction observed and the mechanism that stabilizes this state. The transition temperature to the ferromagnetic state has been calculated within the effective field theory, with a Honmura-Kaneyoshi differential operator technique. - Highlights: Black-Right-Pointing-Pointer The paper focus on the study the magnetic properties and electronic structure of p-type (Ga, Fe)N within LDA and SIC approximation. Black-Right-Pointing-Pointer These methods allow us to explain the strong ferromagnetic interaction observed and the mechanism for its stability and the mechanism of hybridization and interaction between magnetic ions in p-type (Ga, Fe). Black-Right-Pointing-Pointer The results obtained are interesting and can be serve as a reference in the field of dilute magnetic semi conductor.

Salmani, E. [LMPHE, associe au CNRST (URAC 12), Faculte des Sciences, Universite Mohammed V-Agdal, Rabat (Morocco); Mounkachi, O. [Institute of Nanomaterials and Nanotechnology, MAScIR, Rabat (Morocco); Ez-Zahraouy, H., E-mail: ezahamid@fsr.ac.ma [LMPHE, associe au CNRST (URAC 12), Faculte des Sciences, Universite Mohammed V-Agdal, Rabat (Morocco); El Kenz, A. [LMPHE, associe au CNRST (URAC 12), Faculte des Sciences, Universite Mohammed V-Agdal, Rabat (Morocco); Hamedoun, M. [Institute of Nanomaterials and Nanotechnology, MAScIR, Rabat (Morocco); Benyoussef, A. [LMPHE, associe au CNRST (URAC 12), Faculte des Sciences, Universite Mohammed V-Agdal, Rabat (Morocco); Institute of Nanomaterials and Nanotechnology, MAScIR, Rabat (Morocco); Hassan II Academy of Science and Technology, Rabat (Morocco)

2013-03-15

369

Vortex motion in type II superconductors is studied starting from a variant of the time dependent Ginzburg-Landau equations, in which the order parameter relaxation time is taken to be complex. Using a method due to Gor'kov and Kopnin, we derive an equation of motion for a single vortex ($B\\ll H_{c2}$) in the presence of an applied transport current. The imaginary part of the relaxation time and the normal state Hall effect both break ``particle-hole symmetry,'' and produce a component of the vortex velocity parallel to the transport current, and consequently a Hall field due to the vortex motion. Various models for the relaxation time are considered, allowing for a comparison to some phenomenological models of vortex motion in superconductors, such as the Bardeen-Stephen and Nozi\\`eres-Vinen models, as well as to models of vortex motion in neutral superfluids. In addition, the transport energy, Nernst effect, and thermopower are calculated for a single vortex. Vortex bending and fluctuations can also be incl...

Dorsey, A T

1992-01-01

370

Energy Technology Data Exchange (ETDEWEB)

It is shown that the effective Hamiltonian representation, as it is formulated in author's papers, serves as a basis for distinguishing, in a broadband environment of an open quantum system, independent noise sources that determine, in terms of the stationary quantum Wiener and Poisson processes in the Markov approximation, the effective Hamiltonian and the equation for the evolution operator of the open system and its environment. General stochastic differential equations of generalized Langevin (non-Wiener) type for the evolution operator and the kinetic equation for the density matrix of an open system are obtained, which allow one to analyze the dynamics of a wide class of localized open systems in the Markov approximation. The main distinctive features of the dynamics of open quantum systems described in this way are the stabilization of excited states with respect to collective processes and an additional frequency shift of the spectrum of the open system. As an illustration of the general approach developed, the photon dynamics in a single-mode cavity without losses on the mirrors is considered, which contains identical intracavity atoms coupled to the external vacuum electromagnetic field. For some atomic densities, the photons of the cavity mode are 'locked' inside the cavity, thus exhibiting a new phenomenon of radiation trapping and non-Wiener dynamics.

Basharov, A. M., E-mail: basharov@gmail.com [National Research Centre ' Kurchatov Institute,' (Russian Federation)

2012-09-15

371

The necessity of operational risk management and quantification

Directory of Open Access Journals (Sweden)

Full Text Available Beginning with the fact that performant strategies of the financial institutions have programmes and management procedures for the banking risks, which have as main objective to minimize the probability of risk generation and the bank’s potential exposure, this paper wants to present the operational risk management and quantification methods. Also it presents the modality of minimum capital requirement for the operational risk. Therefore, the first part presents the conceptual approach of the operational risks through the point of view of the financial institutions exposed to this type of risk. The second part describes the management and evaluation methods for the operational risk. The final part of this article presents the approach assumed by a financial institution with a precise purpose: the quantification of the minimum capital requirements of the operational risk.

Barbu Teodora Cristina

2008-04-01

372

Investigation of contact mechanical nonlinearities of a mathematical model of corrugation revealed that the typical shape of contact patch resembles a falling drop of water. A contact patch of that shape was approximated with a figure composed of two parts of ellipses with different eccentricities. The contact pressure distribution was assumed as a smoothing ensemble of two paraboloidal distributions. The description of a general case of double half elliptical contact area was given but a special case of double half elliptical contact is more interesting as it possesses some Hertzian properties. It was shown how three geometrical parameters of double half elliptical contact can be chosen when actual, non-Hertzian contact is known. A linear theory was written which indicates that the lateral vibrations of the rail may be excited only due to shape variation on corrugation even if any other cause for these vibrations does not exist. For nonlinear theory a computer program, based on FASTSIM algorithm by Kalker, was written. The aim is to calculate the creep forces and frictional power density distribution over the contact area. Also, a graphic program visualizing the solution was written. Numerical results are not provided; unattended and unsolved problems relevant for this type of contact are listed.

Piotrowski, Jerzy

1991-10-01

373

Impulsivity is considered a personality trait affecting behavior in many life domains, from recreational activities to important decision making. When extreme, it is associated with mental health problems, such as substance use disorders, as well as with interpersonal and social difficulties, including juvenile delinquency and criminality. Yet, trait impulsivity may not be a unitary construct. We review commonly used self-report measures of personality trait impulsivity and related constructs (e.g., sensation seeking), plus the opposite pole, control or constraint. A meta-analytic principal-components factor analysis demonstrated that these scales comprise 3 distinct factors, each of which aligns with a broad, higher order personality factor-Neuroticism/Negative Emotionality, Disinhibition versus Constraint/Conscientiousness, and Extraversion/Positive Emotionality/Sensation Seeking. Moreover, Disinhibition versus Constraint/Conscientiousness comprise 2 correlated but distinct subfactors: Disinhibition versus Constraint and Conscientiousness/Will versus Resourcelessness. We also review laboratory tasks that purport to measure a construct similar to trait impulsivity. A meta-analytic principal-components factor analysis demonstrated that these tasks constitute 4 factors (Inattention, Inhibition, Impulsive Decision-Making, and Shifting). Although relations between these 2 measurement models are consistently low to very low, relations between both trait scales and laboratory behavioral tasks and daily-life impulsive behaviors are moderate. That is, both independently predict problematic daily-life impulsive behaviors, such as substance use, gambling, and delinquency; their joint use has incremental predictive power over the use of either type of measure alone and furthers our understanding of these important, problematic behaviors. Future use of confirmatory methods should help to ascertain with greater precision the number of and relations between impulsivity-related components. PMID:24099400

Sharma, Leigh; Markon, Kristian E; Clark, Lee Anna

2014-03-01

374

Scientific Electronic Library Online (English)

Full Text Available SciELO Peru | Language: Spanish Abstract in spanish La llanura amazónica peruana se caracteriza por la presencia de múltiples formaciones vegetales. Éstas cada vez reciben mayor impacto por actividades antropogénicas tales como la minería y tala. Todo esto, sumado al cambio climático global, genera desconcierto sobre el futuro de los bosques. La iden [...] tificación de los niveles de almacenamiento de carbono en áreas boscosas, y específicamente en cada formación vegetal, permitiría un mejor manejo de las zonas de conservación, así como identificar las áreas potenciales que servirían para el financiamiento de la absorción de carbono y otros servicios ambientales. El presente estudio fue desarrollado en la estación Biológica del Centro de Investigación y Capacitación Río Los Amigos (CICRA). En el CICRA se identificaron tres formaciones vegetales principales, el bosque de terraza, el bosque inundable y el aguajal. Siendo los bosques de terraza los de mayor extensión y mayor cantidad de carbono acumulado. Como resultado se valorizó la vegetación presente en el CICRA, en alrededor de 11 millones de dólares americanos. El ingreso a la oferta de los bonos de carbono promovería la conservación de los bosques. Abstract in english The Peruvian Amazon Basin is characterized by the presence of multiple vegetation types. They are being given great impact by human activities such as mining and, logging. All this, coupled with global climate change, creates confusion about the future of our forests. The identification of levels of [...] carbon storage in forested areas, and specifically in each vegetation type, would allow better management of conservation areas, and then identify potential areas that could serve to finance carbon sequestration and other environmental services. This study was conducted at the Biological Station for Research and Training Center Rio Los Amigos (CICRA, Spanish acronym). At the station three main formations were identified, alluvial terrace forests, flood terrace forests and Mauritia swamps. The alluvial terrace forest presents the most extensive area and the highest amount of carbon stored. As result, CICRA vegetations were valued at approx. 11 millions U.S. dollars. Admission to the supply of carbon credits could promote Amazon forest conservation.

Carlos, Martel; Lianka, Cairampoma.

375

Scientific Electronic Library Online (English)

Full Text Available SciELO Peru | Language: Spanish Abstract in spanish La llanura amazónica peruana se caracteriza por la presencia de múltiples formaciones vegetales. Éstas cada vez reciben mayor impacto por actividades antropogénicas tales como la minería y tala. Todo esto, sumado al cambio climático global, genera desconcierto sobre el futuro de los bosques. La iden [...] tificación de los niveles de almacenamiento de carbono en áreas boscosas, y específicamente en cada formación vegetal, permitiría un mejor manejo de las zonas de conservación, así como identificar las áreas potenciales que servirían para el financiamiento de la absorción de carbono y otros servicios ambientales. El presente estudio fue desarrollado en la estación Biológica del Centro de Investigación y Capacitación Río Los Amigos (CICRA). En el CICRA se identificaron tres formaciones vegetales principales, el bosque de terraza, el bosque inundable y el aguajal. Siendo los bosques de terraza los de mayor extensión y mayor cantidad de carbono acumulado. Como resultado se valorizó la vegetación presente en el CICRA, en alrededor de 11 millones de dólares americanos. El ingreso a la oferta de los bonos de carbono promovería la conservación de los bosques. Abstract in english The Peruvian Amazon Basin is characterized by the presence of multiple vegetation types. They are being given great impact by human activities such as mining and, logging. All this, coupled with global climate change, creates confusion about the future of our forests. The identification of levels of [...] carbon storage in forested areas, and specifically in each vegetation type, would allow better management of conservation areas, and then identify potential areas that could serve to finance carbon sequestration and other environmental services. This study was conducted at the Biological Station for Research and Training Center Rio Los Amigos (CICRA, Spanish acronym). At the station three main formations were identified, alluvial terrace forests, flood terrace forests and Mauritia swamps. The alluvial terrace forest presents the most extensive area and the highest amount of carbon stored. As result, CICRA vegetations were valued at approx. 11 millions U.S. dollars. Admission to the supply of carbon credits could promote Amazon forest conservation.

Carlos, Martel; Lianka, Cairampoma.

2012-08-01

376

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Aerobic physical activity (PA and resistance training are paramount in the treatment and management of type 2 diabetes (T2D, but few studies have examined the determinants of both types of exercise in the same sample. Objective The primary purpose was to investigate the utility of the Theory of Planned Behavior (TPB in explaining aerobic PA and resistance training in a population sample of T2D adults. Methods A total of 244 individuals were recruited through a random national sample which was created by generating a random list of household phone numbers. The list was proportionate to the actual number of household telephone numbers for each Canadian province (with the exception of Quebec. These individuals completed self-report TPB constructs of attitude, subjective norm, perceived behavioral control and intention, and a 3-month follow-up that assessed aerobic PA and resistance training. Results TPB explained 10% and 8% of the variance respectively for aerobic PA and resistance training; and accounted for 39% and 45% of the variance respectively for aerobic PA and resistance training intentions. Conclusion These results may guide the development of appropriate PA interventions for aerobic PA and resistance training based on the TPB.

Karunamuni Nandini

2008-12-01

377

International Nuclear Information System (INIS)

survive quantization. This point is considered in section 8. We present a detailed analysis of the beta function in certain Witten type theories, and compute one-loop effects in Chern-Simons theory. (orig./HSI)

378

Development of Quantification Method for Bioluminescence Imaging

Energy Technology Data Exchange (ETDEWEB)

Optical molecular luminescence imaging is widely used for detection and imaging of bio-photons emitted by luminescent luciferase activation. The measured photons in this method provide the degree of molecular alteration or cell numbers with the advantage of high signal-to-noise ratio. To extract useful information from the measured results, the analysis based on a proper quantification method is necessary. In this research, we propose a quantification method presenting linear response of measured light signal to measurement time. We detected the luminescence signal by using lab-made optical imaging equipment of animal light imaging system (ALIS) and different two kinds of light sources. One is three bacterial light-emitting sources containing different number of bacteria. The other is three different non-bacterial light sources emitting very weak light. By using the concept of the candela and the flux, we could derive simplified linear quantification formula. After experimentally measuring light intensity, the data was processed with the proposed quantification function. We could obtain linear response of photon counts to measurement time by applying the pre-determined quantification function. The ratio of the re-calculated photon counts and measurement time present a constant value although different light source was applied. The quantification function for linear response could be applicable to the standard quantification process. The proposed method could be used for the exact quantitative analysis in various light imaging equipment with presenting linear response behavior of constant light emitting sources to measurement time

Kim, Hyeon Sik; Min, Jung Joon; Lee, Byeong Il [Chonnam National University Hospital, Hwasun (Korea, Republic of); Choi, Eun Seo [Chosun University, Gwangju (Korea, Republic of); Tak, Yoon O; Choi, Heung Kook; Lee, Ju Young [Inje University, Kimhae (Korea, Republic of)

2009-10-15

379

Iodine quantification by analytical ion microscopy (AIM)

International Nuclear Information System (INIS)

AIM allows imaging and quantification of all elements on a biological tissue section. However quantification is limited by physical parameters which are difficult to assess and which intervene for a given element in the relation between its concentration and the measured signal. Thus, to quantify iodine in thyroid follicles, an iodine standard was prepared. Homogeneity in its atomic iodine distribution was tested by surface and depth analyses. Then, a standard curve was generated to be used as a reference for quantification of iodine on histological preparation by AIM

380

Direct qPCR quantification using the Quantifiler(®) Trio DNA quantification kit.

The effectiveness of a direct quantification assay is essential to the adoption of the combined direct quantification/direct STR workflow. In this paper, the feasibility of using the Quantifiler(®) Trio DNA quantification kit for the direct quantification of forensic casework samples was investigated. Both low-level touch DNA samples and blood samples were collected on PE swabs and quantified directly. The increased sensitivity of the Quantifiler(®) Trio kit enabled the detection of less than 10pg of DNA in unprocessed touch samples and also minimizes the stochastic effect experienced by different targets in the same sample. The DNA quantity information obtained from a direct quantification assay using the Quantifiler(®) Trio kit can also be used to accurately estimate the optimal input DNA quantity for a direct STR amplification reaction. The correlation between the direct quantification results (Quantifiler(®) Trio kit) and the direct STR results (GlobalFiler™ PCR amplification kit(*)) for low-level touch DNA samples indicates that direct quantification using the Quantifiler(®) Trio DNA quantification kit is more reliable than the Quantifiler(®) Duo DNA quantification kit for predicting the STR results of unprocessed touch DNA samples containing less than 10pg of DNA. PMID:25047573

Liu, Jason Yingjie

2014-11-01

381

The NASA Langley Multidisciplinary Uncertainty Quantification Challenge

This paper presents the formulation of an uncertainty quantification challenge problem consisting of five subproblems. These problems focus on key aspects of uncertainty characterization, sensitivity analysis, uncertainty propagation, extreme-case analysis, and robust design.

Crespo, Luis G.; Kenny, Sean P.; Giesy, Daniel P.

2014-01-01

382

One-step RT-droplet digital PCR: a breakthrough in the quantification of waterborne RNA viruses.

Water contamination by viruses has an increasing worldwide impact on human health, and has led to requirements for accurate and quantitative molecular tools. Here, we report the first one-step reverse-transcription droplet digital PCR-based absolute quantification of a RNA virus (rotavirus) in different types of surface water samples. This quantification method proved to be more precise and more tolerant to inhibitory substances than the benchmarking reverse-transcription real-time PCR (RT-qPCR), and needs no standard curve. This new tool is fully amenable for the quantification of viruses in the particularly low concentrations usually found in water samples. PMID:24276251

Ra?ki, Nejc; Morisset, Dany; Gutierrez-Aguirre, Ion; Ravnikar, Maja

2014-01-01

383

Directory of Open Access Journals (Sweden)

Full Text Available Background and Aim: Many studies show that the only way to control diabetes and prevent its debilitating complications is continuous self-care. This study aimed to determine factors affecting self-care behavior of diabetic women in Khoy City, Iran based the extended theory of reasoned action (ETRA. Materials and Methods: A sample of 352 women with type 2 diabetes referring to a Diabetes Clinic in Khoy City in West Azarbaijan Province, Iran participated in the study. Appropriate instruments were designed to measure the relevant variables (diabetes knowledge, personal beliefs, subjective norm, self-efficacy and behavioral intention, and self-care behavior based on ETRA. Reliability and validity of the instruments were determined prior to the study. Statistical analysis of the data was done using the SPSS-version 16 software.Results: Based on the data obtained, the proposed model could predict and explain 41% and 26.2% of the variance of behavioral intention and self-care, respectively, in women with type-2 diabetes. The data also indicated that among the constructs of the model perceived self-efficacy was the strongest predictor for intention for self-care behavior. This construct affected both directly and indirectly self-care behavior. The next strongest predictors were attitudes, social pressures, social norms, and intervals between visiting patients by the treating team.Conclusion: The proposed model can predict self-care behavior very well. Thus, it may form the basis for educational interventions aiming at promoting self-care and, ultimately, controlling diabetes.

Ebrahim Hajizadeh

2011-11-01

384

Quantification model for energy consumption in edification

Directory of Open Access Journals (Sweden)

Full Text Available The research conducted in this paper focuses on the generation of a model for the quantification of energy consumption in building. This is to be done through one of the most relevant environmental impact indicators associated with weight per m^{2} of construction, as well as the energy consumption resulting from the manufacturing process of materials used in building construction.
The practical application of the proposed model on different buildings typologies in Seville, will provide information regarding the building materials, the subsystems and the most relevant construction elements. Hence, we will be able to observe the impact the built surface has on the environment.
The results obtained aim to reference the scientific community, providing quantitative data comparable to other types of buildings and geographical areas. Furthermore, it may also allow the analysis and the characterization of feasible solutions to reduce the environmental impact generated by the different materials, subsystems and construction elements commonly used in the different building types defined in this study.

La investigación realizada en el presente trabajo plantea la generación de un modelo de cuantificación del consumo energético en edificación, a través de uno de los indicadores de impacto ambiental más relevantes asociados al peso por m^{2} de construcción, el consumo energético derivado del proceso de fabricación de los materiales de construcción empleados en edificación.
La aplicación práctica del modelo propuesto sobre diferentes tipologías edificatorias en Sevilla aportará información respecto a los materiales de construcción, subsistemas y elementos constructivos más impactantes, permitiendo visualizar la influencia que presenta la superficie construida en cuanto al impacto ambiental generado.
Los resultados obtenidos pretenden servir de referencia a la comunidad científica, aportando datos numéricos que podrán ser comparados en otras tipologías y ámbitos geográficos, a la vez que permitirán analizar y precisar mejoras en cuanto al impacto ambiental generado por los diferentes materiales, subsistemas y elementos constructivos habitualmente utilizados en las tipologías edificatorias definidas.

Mercader, Mª P.

2012-12-01

385

International Nuclear Information System (INIS)

Recent computational and experimental studies have confirmed that high energy cascades produce clustered defects of both vacancy- and interstitial-types as well as isolated point defects. However, the production probability, configuration, stability and other characteristics of the cascade clusters are not well understood in spite of the fact that clustered defect production would substantially affect the irradiation-induced microstructures and the consequent property changes in a certain range of temperatures and displacement rates. In this work, a model of point defect and cluster evolution in irradiated materials under cascade damage conditions was developed by combining the conventional reaction rate theory and the results from the latest molecular dynamics simulation studies. This paper provides a description of the model and a model-based fundamental investigation of the influence of configuration, production efficiency and the initial size distribution of cascade-produced vacancy clusters. In addition, using the model, issues on characterizing cascade-induced defect production by microstructural analysis will be discussed. In particular, the determination of cascade vacancy cluster configuration, surviving defect production efficiency and cascade-interaction volume is attempted by analyzing the temperature dependence of swelling rate and loop growth rate in austenitic steels and model alloys. (author)

386

Various physical properties of the cubic perovskite-type oxide BiScO 3 have been investigated using the pseudo-potential plane-wave (PP-PW) method based on the density functional theory ( DFT). The computed equilibrium lattice parameters agree well with the available theoretical data. The elastic constants and their pressure dependence are predicted using the static finite strain technique. A set of isotropic elastic parameters and related properties, namely bulk and shear moduli, Young's modulus, Poisson's ratio, average sound velocity and Debye temperature are numerically estimated in the framework of the Voigt-Reuss-Hill approximation for BiScO 3 polycrystalline aggregate. The analysis of the site-projected l-decomposed density of states, charge transfer and charge density shows that bonding is predominantly of ionic nature. We distinguish hybridization between Sc-d states and O- p states in the valence bonding region. Through the quasi-harmonic Debye model, in which the phononic effects are considered, the thermal effect on the lattice constant, bulk modulus, heat capacities and thermal expansion coefficient is calculated.

Ghebouli, M. A.; Ghebouli, B.; Fatmi, M.; Bouhemadou, A.

2011-06-01

387

We perform a detailed study of the type IIA superstring in {text{Ad}}{{text{S}}_4} × mathbb{C}{mathbb{P}_3} . After introducing suitable bosonic light-cone and fermionic kappa worldsheet gauges we derive the pure boson and fermion SU(2|2)×U(1) covariant light-cone Hamiltonian up to quartic order in fields. As a first application of our derivation we calculate energy shifts for string configurations in a closed fermionic subsector and successfully match these with a set of light-cone Bethe equations. We then turn to investigate the mismatch between the degrees of freedom of scattering states and oscillatory string modes. Since only light string modes appear as fundamental Bethe roots in the scattering theory, the physical role of the remaining 4 F + 4 B massive oscillators is rather unclear. By continuing a line of research initiated by Zarembo, we shed light on this question by calculating quantum corrections for the propagators of the bosonic massive fields. We show that, once loop corrections are incorporated, the massive coordinates dissolve in a continuum state of two light particles.

Sundin, Per

2010-04-01

388

Stirling Convertor Fasteners Reliability Quantification

Onboard Radioisotope Power Systems (RPS) being developed for NASA s deep-space science and exploration missions require reliable operation for up to 14 years and beyond. Stirling power conversion is a candidate for use in an RPS because it offers a multifold increase in the conversion efficiency of heat to electric power and reduced inventory of radioactive material. Structural fasteners are responsible to maintain structural integrity of the Stirling power convertor, which is critical to ensure reliable performance during the entire mission. Design of fasteners involve variables related to the fabrication, manufacturing, behavior of fasteners and joining parts material, structural geometry of the joining components, size and spacing of fasteners, mission loads, boundary conditions, etc. These variables have inherent uncertainties, which need to be accounted for in the reliability assessment. This paper describes these uncertainties along with a methodology to quantify the reliability, and provides results of the analysis in terms of quantified reliability and sensitivity of Stirling power conversion reliability to the design variables. Quantification of the reliability includes both structural and functional aspects of the joining components. Based on the results, the paper also describes guidelines to improve the reliability and verification testing.

Shah, Ashwin R.; Korovaichuk, Igor; Kovacevich, Tiodor; Schreiber, Jeffrey G.

2006-01-01

389

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Long term management of patients with Type 2 diabetes is well established within Primary Care. However, despite extensive efforts to implement high quality care both service provision and patient health outcomes remain sub-optimal. Several recent studies suggest that psychological theories about individuals' behaviour can provide a valuable framework for understanding generalisable factors underlying health professionals' clinical behaviour. In the context of the team management of chronic disease such as diabetes, however, the application of such models is less well established. The aim of this study was to identify motivational factors underlying health professional teams' clinical management of diabetes using a psychological model of human behaviour. Methods A predictive questionnaire based on the Theory of Planned Behaviour (TPB investigated health professionals' (HPs' cognitions (e.g., beliefs, attitudes and intentions about the provision of two aspects of care for patients with diabetes: prescribing statins and inspecting feet. General practitioners and practice nurses in England and the Netherlands completed parallel questionnaires, cross-validated for equivalence in English and Dutch. Behavioural data were practice-level patient-reported rates of foot examination and use of statin medication. Relationships between the cognitive antecedents of behaviour proposed by the TPB and healthcare teams' clinical behaviour were explored using multiple regression. Results In both countries, attitude and subjective norm were important predictors of health professionals' intention to inspect feet (Attitude: beta = .40; Subjective Norm: beta = .28; Adjusted R2 = .34, p 2 = .40, p Conclusion Using the TPB, we identified modifiable factors underlying health professionals' intentions to perform two clinical behaviours, providing a rationale for the development of targeted interventions. However, we did not observe a relationship between health professionals' intentions and our proxy measure of team behaviour. Significant methodological issues were highlighted concerning the use of models of individual behaviour to explain behaviours performed by teams. In order to investigate clinical behaviours performed by teams it may be necessary to develop measures that reflect the collective cognitions of the members of the team to facilitate the application of these theoretical models to team behaviours.

Johnston Marie

2009-08-01

390

Dempster-Shafer theory and connections to information theory

The Dempster-Shafer theory is founded on probability theory. The entire machinery of probability theory, and that of measure theory, is at one's disposal for the understanding and the extension of the Dempster-Shafer theory. It is well known that information theory is also founded on probability theory. Claude Shannon developed, in the 1940's, the basic concepts of the theory and demonstrated their utility in communications and coding. Shannonian information theory is not, however, the only type of information theory. In the 1960's and 1970's, further developments in this field were made by French and Italian mathematicians. They developed information theory axiomatically, and discovered not only the Wiener- Shannon composition law, but also the hyperbolic law and the Inf-law. The objective of this paper is to demonstrate the mathematical connections between the Dempster Shafer theory and the various types of information theory. A simple engineering example will be used to demonstrate the utility of the concepts.

Peri, Joseph S. J.

2013-05-01

391

Superspace conformal field theory

International Nuclear Information System (INIS)

Conformal sigma models and WZW models on coset superspaces provide important examples of logarithmic conformal field theories. They possess many applications to problems in string and condensed matter theory. We review recent results and developments, including the general construction of WZW models on type I supergroups, the classification of conformal sigma models and their embedding into string theory.

392

Superspace conformal field theory

Energy Technology Data Exchange (ETDEWEB)

Conformal sigma models and WZW models on coset superspaces provide important examples of logarithmic conformal field theories. They possess many applications to problems in string and condensed matter theory. We review recent results and developments, including the general construction of WZW models on type I supergroups, the classification of conformal sigma models and their embedding into string theory.

Quella, Thomas [Koeln Univ. (Germany). Inst. fuer Theoretische Physik; Schomerus, Volker [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2013-07-15

393

Uncertainty quantification in molecular dynamics

This dissertation focuses on uncertainty quantification (UQ) in molecular dynamics (MD) simulations. The application of UQ to molecular dynamics is motivated by the broad uncertainty characterizing MD potential functions and by the complexity of the MD setting, where even small uncertainties can be amplified to yield large uncertainties in the model predictions. Two fundamental, distinct sources of uncertainty are investigated in this work, namely parametric uncertainty and intrinsic noise. Intrinsic noise is inherently present in the MD setting, due to fluctuations originating from thermal effects. Averaging methods can be exploited to reduce the fluctuations, but due to finite sampling, this effect cannot be completely filtered, thus yielding a residual uncertainty in the MD predictions. Parametric uncertainty, on the contrary, is introduced in the form of uncertain potential parameters, geometry, and/or boundary conditions. We address the UQ problem in both its main components, namely the forward propagation, which aims at characterizing how uncertainty in model parameters affects selected observables, and the inverse problem, which involves the estimation of target model parameters based on a set of observations. The dissertation highlights the challenges arising when parametric uncertainty and intrinsic noise combine to yield non-deterministic, noisy MD predictions of target macroscale observables. Two key probabilistic UQ methods, namely Polynomial Chaos (PC) expansions and Bayesian inference, are exploited to develop a framework that enables one to isolate the impact of parametric uncertainty on the MD predictions and, at the same time, properly quantify the effect of the intrinsic noise. Systematic applications to a suite of problems of increasing complexity lead to the observation that an uncertain PC representation built via Bayesian regression is the most suitable model for the representation of uncertain MD predictions of target observables in the presence of intrinsic noise and parametric uncertainty. The dissertation is organized in successive, self-contained problems of increasing complexity aimed at investigating the target UQ challenge in a progressive fashion.

Rizzi, Francesco

394

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The primary aim of this study was to compare the efficacy of three physical activity (PA behavioural intervention strategies in a sample of adults with type 2 diabetes. Method/Design Participants (N = 287 were randomly assigned to one of three groups consisting of the following intervention strategies: (1 standard printed PA educational materials provided by the Canadian Diabetes Association [i.e., Group 1/control group]; (2 standard printed PA educational materials as in Group 1, pedometers, a log book and printed PA information matched to individuals' PA stage of readiness provided every 3 months (i.e., Group 2; and (3 PA telephone counseling protocol matched to PA stage of readiness and tailored to personal characteristics, in addition to the materials provided in Groups 1 and 2 (i.e., Group 3. PA behaviour measured by the Godin Leisure Time Exercise Questionnaire and related social-cognitive measures were assessed at baseline, 3, 6, 9, 12 and 18-months (i.e., 6-month follow-up. Clinical (biomarkers and health-related quality of life assessments were conducted at baseline, 12-months, and 18-months. Linear Mixed Model (LMM analyses will be used to examine time-dependent changes from baseline across study time points for Groups 2 and 3 relative to Group 1. Discussion ADAPT will determine whether tailored but low-cost interventions can lead to sustainable increases in PA behaviours. The results may have implications for practitioners in designing and implementing theory-based physical activity promotion programs for this population. Clinical Trials Registration ClinicalTrials.gov identifier: NCT00221234

Birkett Nicholas

2010-01-01

395

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Quantitative proteomics technologies have been developed to comprehensively identify and quantify proteins in two or more complex samples. Quantitative proteomics based on differential stable isotope labeling is one of the proteomics quantification technologies. Mass spectrometric data generated for peptide quantification are often noisy, and peak detection and definition require various smoothing filters to remove noise in order to achieve accurate peptide quantification. Many traditional smoothing filters, such as the moving average filter, Savitzky-Golay filter and Gaussian filter, have been used to reduce noise in MS peaks. However, limitations of these filtering approaches often result in inaccurate peptide quantification. Here we present the WaveletQuant program, based on wavelet theory, for better or alternative MS-based proteomic quantification. Results We developed a novel discrete wavelet transform (DWT and a 'Spatial Adaptive Algorithm' to remove noise and to identify true peaks. We programmed and compiled WaveletQuant using Visual C++ 2005 Express Edition. We then incorporated the WaveletQuant program in the Trans-Proteomic Pipeline (TPP, a commonly used open source proteomics analysis pipeline. Conclusions We showed that WaveletQuant was able to quantify more proteins and to quantify them more accurately than the ASAPRatio, a program that performs quantification in the TPP pipeline, first using known mixed ratios of yeast extracts and then using a data set from ovarian cancer cell lysates. The program and its documentation can be downloaded from our website at http://systemsbiozju.org/data/WaveletQuant.

Li Song

2010-04-01

396

Quantification of Information in a One-Way Plant-to-Animal Communication System

Digital Repository Infrastructure Vision for European Research (DRIVER)

In order to demonstrate possible broader applications of information theory to the quantification of non-human communication systems, we apply calculations of information entropy to a simple chemical communication from the cotton plant (Gossypium hirsutum) to the wasp (Cardiochiles nigriceps) studied by DeMoraes et al. The purpose of this chemical communication from cotton plants to wasps is presumed to be to allow the predatory wasp to more easily obtain the location of its preferred prey—...

Doyle, Laurance R.

2009-01-01

397

A new approach to the evaluation and quantification of human reliability in systems assessment

International Nuclear Information System (INIS)

The importance of human reliability considerations in risk assessment is considered. The shortcomings of existing approaches are discussed and the problems of data collection in this area are analysed. A new approach is proposed based on the use of Multi-Attribute Utility Theory. Detailed procedures for applying this approach to the qualitative assessment of human reliability are given. Finally, the extension of the technique to quantification is discussed. (author)

398

Pancreas++ : Automated Quantification of Pancreatic Islet Cells in Microscopy Images

Directory of Open Access Journals (Sweden)

Full Text Available The microscopic image analysis of pancreatic Islet of Langerhans morphology is crucial for the investigation of diabetes and metabolic diseases. Besides the general size of the islet, the percentage and relative position of glucagon-containing alpha-, and insulin-containing beta-cells is also important for pathophysiological analyses, especially in rodents. Hence, the ability to identify, quantify and spatially locate peripheral and ‘involuted’ alpha-cells in the islet core is an important analytical goal. There is a dearth of software available for the automated and sophisticated positional-quantification of multiple cell types in the islet core. Manual analytical methods for these analyses, while relatively accurate, can suffer from a slow throughput rate as well as user-based biases. Here we describe a newly developed pancreatic islet analytical software program, Pancreas++, which facilitates the fully-automated, non-biased, and highly reproducible investigation of islet area and alpha- and beta-cell quantity as well as position within the islet for either single or large batches of fluorescent images. We demonstrate the utility and accuracy of Pancreas++ by comparing its performance to other pancreatic islet size and cell type (alpha, beta quantification methods. Our Pancreas++ analysis was significantly faster than other methods, while still retaining low error rates and a high degree of result correlation with the manually generated reference standard.

StuartMaudsley

2013-01-01

399

DEFF Research Database (Denmark)

Kenneth N. Waltz's 1979 book, Theory of International Politics, is the most influential in the history of the discipline. It worked its effects to a large extent through raising the bar for what counted as theoretical work, in effect reshaping not only realism but rivals like liberalism and reflectivism. Yet, ironically, there has been little attention to Waltz's very explicit and original arguments about the nature of theory. This article explores and explicates Waltz's theory of theory. Central attention is paid to his definition of theory as ‘a picture, mentally formed' and to the radical anti-empiricism and anti-positivism of his position. Followers and critics alike have treated Waltzian neorealism as if it was at bottom a formal proposition about cause-effect relations. The extreme case of Waltz being so victorious in the discipline, and yet being consistently mis-interpreted on the question of theory, shows the power of a dominant philosophy of science in US IR, and thus the challenge facing any ambitious theorising. The article suggests a possible movement of fronts away from the ‘fourth debate' between rationalism and reflectivism towards one of theory against empiricism. To help this new agenda, the article introduces a key literature from philosophy of science about the structure of theory, and particularly about the way even natural science uses theory very differently from what IRs mainstream thinks - and much more like the way Waltz wants his theory used.

Wæver, Ole

2009-01-01

400

Quantification of brain lipids by FTIR spectroscopy and partial least squares regression

Brain tissue is characterized by high lipid content. Its content decreases and the lipid composition changes during transformation from normal brain tissue to tumors. Therefore, the analysis of brain lipids might complement the existing diagnostic tools to determine the tumor type and tumor grade. Objective of this work is to extract lipids from gray matter and white matter of porcine brain tissue, record infrared (IR) spectra of these extracts and develop a quantification model for the main lipids based on partial least squares (PLS) regression. IR spectra of the pure lipids cholesterol, cholesterol ester, phosphatidic acid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, sphingomyelin, galactocerebroside and sulfatide were used as references. Two lipid mixtures were prepared for training and validation of the quantification model. The composition of lipid extracts that were predicted by the PLS regression of IR spectra was compared with lipid quantification by thin layer chromatography.

Dreissig, Isabell; Machill, Susanne; Salzer, Reiner; Krafft, Christoph

2009-01-01

401

Model based quantification of EELS spectra

International Nuclear Information System (INIS)

Recent advances in model based quantification of electron energy loss spectra (EELS) are reported. The maximum likelihood method for the estimation of physical parameters describing an EELS spectrum, the validation of the model used in this estimation procedure, and the computation of the attainable precision, that is, the theoretical lower bound on the variance of these estimates, are discussed. Experimental examples on Au and GaAs samples show the power of the maximum likelihood method and show that the theoretical prediction of the attainable precision can be closely approached even for spectra with overlapping edges where conventional EELS quantification fails. To provide end-users with a low threshold alternative to conventional quantification, a user friendly program was developed which is freely available under a GNU public license

402

Inverse problems Tikhonov theory and algorithms

Inverse problems arise in practical applications whenever one needs to deduce unknowns from observables. This monograph is a valuable contribution to the highly topical field of computational inverse problems. Both mathematical theory and numerical algorithms for model-based inverse problems are discussed in detail. The mathematical theory focuses on nonsmooth Tikhonov regularization for linear and nonlinear inverse problems. The computational methods include nonsmooth optimization algorithms, direct inversion methods and uncertainty quantification via Bayesian inference. The book offers a com

Ito, Kazufumi

2014-01-01

403

Directory of Open Access Journals (Sweden)

Full Text Available The hydration free energy of hard-sphere solute is evaluated over a wide range of size using the method of energy representation, information-theoretic approach, reference interaction site model, and scaled-particle theory. The former three are distribution function theories and the hydration free energy is formulated to reflect the solution structure through distribution functions. The presence of the volume-dependent term is pointed out for the distribution function theories, and the asymptotic behavior in the limit of large solute size is identified. It is indicated that the volume-dependent term is a key to the improvement of distribution function theories toward the application to large molecules.

N.Matubayasi

2007-12-01

404

Briefly reviews Farley's Type T theory of personality and then considers a range of issues in marital therapy from the perspective of Type T. Suggests that Type T theory may be relevant in dealing with infidelity, sexual problems, love, marital abuse, child rearing, drug and alcohol use, money, division of household labor, recreation, and…

Farley, Frank; Carlson, Jon

1991-01-01

405

Quantification of fuel rod cladding failure during LOCA accident

International Nuclear Information System (INIS)

The paper describes methodology for quantification of fuel cladding failure as a result of Loss of Coolant Accident (LOCA) for WWER-440 reactor type. The methodology is based on external coupling of the thermo-hydraulic code RELAP5 and thermo-mechanical code TRANSURANUS. The thermo-hydraulic response of the unit to the accident is simulated by RELAP5 code, providing initial and boundary conditions for the thermo-mechanical simulation by the TRANSURANUS code. Cladding failure criterion of the TRANSURANUS code, derived and implemented into the code in the framework of EXTRA EURATOM fifth Framework Programme is used. Cladding failure probability is evaluated by the Monte Carlo algorithm varying the outer cladding temperature. In the second part of the paper, an example of application of the methodology for typical maximum design accident of the WWER-440 is given, presenting every step of methodology and typical failure rate for this type of accident (Authors)

406

Two consanguineous families with Uner Tan Syndrome (UTS) were analyzed in relation to self-organizing processes in complex systems, and the evolutionary emergence of human bipedalism. The cases had the key symptoms of previously reported cases of UTS, such as quadrupedalism, mental retardation, and dysarthric or no speech, but the new cases also exhibited infantile hypotonia and are designated UTS Type-II. There were 10 siblings in Branch I and 12 siblings in Branch II. Of these, there were seven cases exhibiting habitual quadrupedal locomotion (QL): four deceased and three living. The infantile hypotonia in the surviving cases gradually disappeared over a period of years, so that they could sit by about 10 years, crawl on hands and knees by about 12 years. They began walking on all fours around 14 years, habitually using QL. Neurological examinations showed normal tonus in their arms and legs, no Babinski sign, brisk tendon reflexes especially in the legs, and mild tremor. The patients could not walk in a straight line, but (except in one case) could stand up and maintain upright posture with truncal ataxia. Cerebello-vermial hypoplasia and mild gyral simplification were noted in their MRIs. The results of the genetic analysis were inconclusive: no genetic code could be identified as the triggering factor for the syndrome in these families. Instead, the extremely low socio-economic status of the patients was thought to play a role in the emergence of UTS, possibly by epigenetically changing the brain structure and function, with a consequent selection of ancestral neural networks for QL during locomotor development. It was suggested that UTS may be regarded as one of the unpredictable outcomes of self-organization within a complex system. It was also noted that the prominent feature of this syndrome, the diagonal-sequence habitual QL, generated an interference between ipsilateral hands and feet, as in non-human primates. It was suggested that this may have been the triggering factor for the attractor state "bipedal locomotion" (BL), which had visual and manual benefits for our ape-like ancestors, and therefore enhancing their chances for survival, with consequent developments in the psychomotor domain of humans. This was put forward as a novel theory of the evolution of BL in human beings. PMID:24795558

Tan, Uner

2014-01-01

407

Advancing agricultural greenhouse gas quantification*

1. Introduction Better information on greenhouse gas (GHG) emissions and mitigation potential in the agricultural sector is necessary to manage these emissions and identify responses that are consistent with the food security and economic development priorities of countries. Critical activity data (what crops or livestock are managed in what way) are poor or lacking for many agricultural systems, especially in developing countries. In addition, the currently available methods for quantifying emissions and mitigation are often too expensive or complex or not sufficiently user friendly for widespread use. The purpose of this focus issue is to capture the state of the art in quantifying greenhouse gases from agricultural systems, with the goal of better understanding our current capabilities and near-term potential for improvement, with particular attention to quantification issues relevant to smallholders in developing countries. This work is timely in light of international discussions and negotiations around how agriculture should be included in efforts to reduce and adapt to climate change impacts, and considering that significant climate financing to developing countries in post-2012 agreements may be linked to their increased ability to identify and report GHG emissions (Murphy et al 2010, CCAFS 2011, FAO 2011). 2. Agriculture and climate change mitigation The main agricultural GHGs—methane and nitrous oxide—account for 10%-12% of anthropogenic emissions globally (Smith et al 2008), or around 50% and 60% of total anthropogenic methane and nitrous oxide emissions, respectively, in 2005. Net carbon dioxide fluxes between agricultural land and the atmosphere linked to food production are relatively small, although significant carbon emissions are associated with degradation of organic soils for plantations in tropical regions (Smith et al 2007, FAO 2012). Population growth and shifts in dietary patterns toward more meat and dairy consumption will lead to increased emissions unless we improve production efficiencies and management. Developing countries currently account for about three-quarters of direct emissions and are expected to be the most rapidly growing emission sources in the future (FAO 2011). Reducing agricultural emissions and increasing carbon sequestration in the soil and biomass has the potential to reduce agriculture's contribution to climate change by 5.5-6.0 gigatons (Gt) of carbon dioxide equivalent (CO2eq)/year. Economic potentials, which take into account costs of implementation, range from 1.5 to 4.3 GT CO2eq/year, depending on marginal abatement costs assumed and financial resources committed, with most of this potential in developing countries (Smith et al 2007). The opportunity for mitigation in agriculture is thus significant, and, if realized, would contribute to making this sector carbon neutral. Yet it is only through a robust and shared understanding of how much carbon can be stored or how much CO2 is reduced from mitigation practices that informed decisions can be made about how to identify, implement, and balance a suite of mitigation practices as diverse as enhancing soil organic matter, increasing the digestibility of feed for cattle, and increasing the efficiency of nitrogen fertilizer applications. Only by selecting a portfolio of options adapted to regional characteristics and goals can mitigation needs be best matched to also serve rural development goals, including food security and increased resilience to climate change. Expansion of agricultural land also remains a major contributor of greenhouse gases, with deforestation, largely linked to clearing of land for cultivation or pasture, generating 80% of emissions from developing countries (Hosonuma et al 2012). There are clear opportunities for these countries to address mitigation strategies from the forest and agriculture sector, recognizing that agriculture plays a large role in economic and development potential. In this context, multiple development goals can be reinforced by specific climate funding granted on the basis of

Olander, Lydia; Wollenberg, Eva; Tubiello, Francesco; Herold, Martin

2013-03-01

408

Dependent dreams: recounting types

Digital Repository Infrastructure Vision for European Research (DRIVER)

We investigate the class of models of a general dependent theory. We continue math.LO/0702292 in particular investigating so called "decomposition of types"; thesis is that what holds for stable theory and for Th(Q,<) hold for dependent theories. Another way to say this is: we have to look at small enough neighborhood and use reasonably definable types to analyze a type. We note the results understable without reading. First, a parallel to the "stability spectrum", the "reco...

Shelah, Saharon

2012-01-01

409

Extended Forward Sensitivity Analysis for Uncertainty Quantification

Energy Technology Data Exchange (ETDEWEB)

Verification and validation (V&V) are playing more important roles to quantify uncertainties and realize high fidelity simulations in engineering system analyses, such as transients happened in a complex nuclear reactor system. Traditional V&V in the reactor system analysis focused more on the validation part or did not differentiate verification and validation. The traditional approach to uncertainty quantification is based on a 'black box' approach. The simulation tool is treated as an unknown signal generator, a distribution of inputs according to assumed probability density functions is sent in and the distribution of the outputs is measured and correlated back to the original input distribution. The 'black box' method mixes numerical errors with all other uncertainties. It is also not efficient to perform sensitivity analysis. Contrary to the 'black box' method, a more efficient sensitivity approach can take advantage of intimate knowledge of the simulation code. In these types of approaches equations for the propagation of uncertainty are constructed and the sensitivities are directly solved for as variables in the simulation. This paper presents the forward sensitivity analysis as a method to help uncertainty qualification. By including time step and potentially spatial step as special sensitivity parameters, the forward sensitivity method is extended as one method to quantify numerical errors. Note that by integrating local truncation errors over the whole system through the forward sensitivity analysis process, the generated time step and spatial step sensitivity information reflect global numerical errors. The discretization errors can be systematically compared against uncertainties due to other physical parameters. This extension makes the forward sensitivity method a much more powerful tool to help uncertainty qualification. By knowing the relative sensitivity of time and space steps with other interested physical parameters, the simulation is allowed to run at optimized time and space steps without affecting the confidence of the physical parameter sensitivity results. The time and space steps forward sensitivity analysis method can also replace the traditional time step and grid convergence study with much less computational cost. Several well defined benchmark problems with manufactured solutions are utilized to demonstrate the extended forward sensitivity analysis method. All the physical solutions, parameter sensitivity solutions, even the time step sensitivity in one case, have analytical forms, which allows the verification to be performed in the strictest sense.

Haihua Zhao; Vincent A. Mousseau

2011-09-01

410

Uncertainty quantification in aerosol dynamics

International Nuclear Information System (INIS)

The influence of uncertainty in coagulation and depositions mechanisms, as well as in the initial conditions, on the solution of the aerosol dynamic equation have been assessed using polynomial chaos theory. In this way, large uncertainties can be incorporated into the equations and their propagation as a function of space and time studied. We base our calculations on the simplified point model dynamic equation which includes coagulation and deposition removal mechanisms. Results are given for the stochastic mean aerosol density as a function of time as well as its variance. The stochastic mean and deterministic mean are shown to differ and the associated uncertainty, in the form of a sensitivity coefficient, is obtained as a function of time. In addition, we obtain the probability density function of the aerosol density and show how this varies with time. In view of the generally uncertain nature of an accidental aerosol release in a nuclear reactor accident, the polynomial chaos method is a particularly useful technique as it allows one to deal with a very large spread of input data and examine the effect this has on the quantities of interest. Convergence matters are studied and numerical values given.

411

Digital Repository Infrastructure Vision for European Research (DRIVER)

We describe a type system for a platform called the General Intensional Programming System (GIPSY), designed to support intensional programming languages built upon intensional logic and their imperative counter-parts for the intensional execution model. In GIPSY, the type system glues the static and dynamic typing between intensional and imperative languages in its compiler and run-time environments to support the intensional evaluation of expressions written in various dia...

Mokhov, Serguei A.; Paquet, Joey

2009-01-01

412

Quantification of atherosclerosis with MRI

International Nuclear Information System (INIS)

Cardiovascular disease due to atherosclerosis is a major cause of death in the United States. A major limitation in the current treatment of atherosclerosis is the lack of a quantitative means to non-invasively evaluate the extent of the disease. Recent studies suggest that Magnetic Resonance Imaging (MRI) has the potential for the detection of atherosclerotic plaque. It has been demonstrated that multi-dimensional pattern recognition can be applied to multi-pulse sequence MR images to identify different tissue types. The authors reported the identification of tissues involved in the atherosclerotic disease process, such as normal endothelium, smooth muscle, thrombus, fat or lipid, connective tissue and calcified plaque. The work reported in this abstract presents preliminary results of applying quantitative 3-D reconstruction to the problem of identifying and quantifying atherosclerotic plaque in vitro

413

Residual transglutaminase in collagen - effects, detection, quantification, and removal.

In the present study, we developed an enzyme-linked immunosorbent assay (ELISA) for microbial transglutaminase (mTG) from Streptomyces mobaraensis to overcome the lack of a quantification method for mTG. We further performed a detailed follow-on-analysis of insoluble porcine collagen type I enzymatically modified with mTG primarily focusing on residuals of mTG. Repeated washing (4 ×) reduced mTG-levels in the washing fluids but did not quantitatively remove mTG from the material (p < 0.000001). Substantial amounts of up to 40% of the enzyme utilized in the crosslinking mixture remained associated with the modified collagen. Binding was non-covalent as could be demonstrated by Western blot analysis. Acidic and alkaline dialysis of mTG treated collagen material enabled complete removal the enzyme. Treatment with guanidinium chloride, urea, or sodium chloride was less effective in reducing the mTG content. PMID:22079174

Schloegl, W; Klein, A; Fürst, R; Leicht, U; Volkmer, E; Schieker, M; Jus, S; Guebitz, G M; Stachel, I; Meyer, M; Wiggenhorn, M; Friess, W

2012-02-01

414

Introduction to superstring theory

Energy Technology Data Exchange (ETDEWEB)

This is a very basic introduction to the AdS/CFT correspondence. The first lecture motivates the duality between gauge theories and gravity/string theories. The next two lectures introduce the bosonic and supersymmetric string theories. The fourth lecture is devoted to study Dp-branes and finally, in the fifth lecture I discuss the two worlds: N=4 SYM in 3+1 flat dimensions and type IIB superstrings in AdS{sub 5} x S5. (author)

Nunez, Carmen [Instituto de Astronomia y Fisica del Espacio, Buenos Aires (Argentina)], e-mail: carmen@iafe.uba.ar

2009-07-01

415

Introduction to superstring theory

International Nuclear Information System (INIS)

This is a very basic introduction to the AdS/CFT correspondence. The first lecture motivates the duality between gauge theories and gravity/string theories. The next two lectures introduce the bosonic and supersymmetric string theories. The fourth lecture is devoted to study Dp-branes and finally, in the fifth lecture I discuss the two worlds: N=4 SYM in 3+1 flat dimensions and type IIB superstrings in AdS5 x S5. (author)

416

Automatic quantification in lung scintigraphy: functional atlas

International Nuclear Information System (INIS)

In spite of the development of new techniques, the ventilation perfusion lung scintigraphy keeps a good place for the diagnosis of pulmonary embolism (PE). In the context of an improvement of reliability and reproducibility of the diagnosis, this study proposes to realize an automatic quantification of the distribution of the radioactive tracers by pulmonary segments. Measurements are made following a procedure of non-rigid matching of morphological 2-D charts of the lungs on the scintigraphic images. The adaptation of these charts to the patients' morphology is carried out by exploiting iso-contour information of the images and using Fourier descriptors to determine the parameters of the transformation. The study was performed on a population of 30 patients with a probability of nil of the pulmonary embolism. After a study of the robustness of the quantification, 2-D segmental functional reference charts (according to the conditions of acquisition) were proposed. In the perfusion case and four views, the following lobar distribution, in relative value, is measured: Right Inferior Lobar = 23,39%, Medial Lobar = 10,41 %, Right Superior Lobar = 20,37%, Left Inferior Lobar 20,6% and Left Superior Lobar = 25.6% with culmen = 18,8% and lingula = 6,8%; values comparable with those of the publication. The process of quantification is adaptable to the ventilation lung scans. The segmental quantifications of a patient carried out under the same conditions of acquisition as the the same conditions of acquisition as the functional reference charts, could be compared with the reference data and provide indicators for the diagnosis but also for patient follow-up and preoperative evaluation of lung cancers. (authors)

417

Digital Repository Infrastructure Vision for European Research (DRIVER)

We propose a new concept of entanglement for quantum systems: entanglement in theory space. This is defined by decomposing a theory into two by an un-gauging procedure. We provide two examples where this newly-introduced entanglement is closely related with conventional geometric entropies: deconstruction and AGT-type correspondence.

Yamazaki, Masahito

2013-01-01

418

Automated quantification of synapses by fluorescence microscopy.

The quantification of synapses in neuronal cultures is essential in studies of the molecular mechanisms underlying synaptogenesis and synaptic plasticity. Conventional counting of synapses based on morphological or immunocytochemical criteria is extremely work-intensive. We developed a fully automated method which quantifies synaptic elements and complete synapses based on immunocytochemistry. Pre- and postsynaptic elements are detected by their corresponding fluorescence signals and their proximity to dendrites. Synapses are defined as the combination of a pre- and postsynaptic element within a given distance. The analysis is performed in three dimensions and all parameters required for quantification can be easily adjusted by a graphical user interface. The integrated batch processing enables the analysis of large datasets without any further user interaction and is therefore efficient and timesaving. The potential of this method was demonstrated by an extensive quantification of synapses in neuronal cultures from DIV 7 to DIV 21. The method can be applied to all datasets containing a pre- and postsynaptic labeling plus a dendritic or cell surface marker. PMID:22108140

Schätzle, Philipp; Wuttke, René; Ziegler, Urs; Sonderegger, Peter

2012-02-15

419

Quantification of water uptake by soot particles

International Nuclear Information System (INIS)

Quantification of atmospheric processes including the water uptake by soot particles of various origin, emitted from different sources, requires identification of hydrophobic and hydrophilic soot. Water uptake measurements are performed on well-characterized laboratory soots available for atmospheric studies. Comparative analysis of water adsorption isotherms on soots of various compositions allows us to suggest a concept of quantification. Systematic analysis demonstrates two mechanisms of water/soot interaction, namely, bulk dissolution into soot-water-soluble coverage (absorption mechanism) and water molecule adsorption on surface active sites (adsorption mechanism). The formation of water film extended over the surface is suggested as a quantification measure which separates hygroscopic from non-hygroscopic soot. Water uptake on hygroscopic soot takes place by the absorption mechanism: it significantly exceeds the formation of many surface layers. If soot particles are made mostly from elemental carbon and/or are covered by a water-insoluble organic layer, they are classified as non-hygroscopic. Low water adsorption on some active sites following cluster formation is a typical mechanism of water interaction with hydrophobic soot. If a water film extended over the surface is formed due to the cluster confluence it is suggested that soot is hydrophilic. A few classical models are applied for parameterization of water interactions on hydrophilic and hydrophobic sootstions on hydrophilic and hydrophobic soots

420

Phylogenetic quantification of intra-tumour heterogeneity.

Intra-tumour genetic heterogeneity is the result of ongoing evolutionary change within each cancer. The expansion of genetically distinct sub-clonal populations may explain the emergence of drug resistance, and if so, would have prognostic and predictive utility. However, methods for objectively quantifying tumour heterogeneity have been missing and are particularly difficult to establish in cancers where predominant copy number variation prevents accurate phylogenetic reconstruction owing to horizontal dependencies caused by long and cascading genomic rearrangements. To address these challenges, we present MEDICC, a method for phylogenetic reconstruction and heterogeneity quantification based on a Minimum Event Distance for Intra-tumour Copy-number Comparisons. Using a transducer-based pairwise comparison function, we determine optimal phasing of major and minor alleles, as well as evolutionary distances between samples, and are able to reconstruct ancestral genomes. Rigorous simulations and an extensive clinical study show the power of our method, which outperforms state-of-the-art competitors in reconstruction accuracy, and additionally allows unbiased numerical quantification of tumour heterogeneity. Accurate quantification and evolutionary inference are essential to understand the functional consequences of tumour heterogeneity. The MEDICC algorithms are independent of the experimental techniques used and are applicable to both next-generation sequencing and array CGH data. PMID:24743184

Schwarz, Roland F; Trinh, Anne; Sipos, Botond; Brenton, James D; Goldman, Nick; Markowetz, Florian

2014-04-01