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Sample records for bcs theory

  1. Mathematical aspects of the BCS theory of superconductivity and related theories

    International Nuclear Information System (INIS)

    Braeunlich, Gerhard Albert

    2014-01-01

    The present work starts with a introduction to the BCS theory, describing superconductivity and superfluidity. The main part consist of a collection of three publications and a paper included in a conference proceedings. The introduction (Chapter 1) includes a brief historical review of the research in the field of superconductivity and superfluidity. It ends with a short summary of the technical applications of superconductivity. In Chapter 2, a derivation of the BCS functional from quantum statistics is presented. Chapter 3 explains the results of the publications mentioned above. In a first work, the validity of the negligence of the direct and exchange energy in the derivation of the BCS functional is examined. Another work addresses the connection between the BCS theory and the Gross-Pitaevskii equation.

  2. Solution Theory of Ginzburg-Landau Theory on BCS-BEC Crossover

    Directory of Open Access Journals (Sweden)

    Shuhong Chen

    2014-01-01

    Full Text Available We establish strong solution theory of time-dependent Ginzburg-Landau (TDGL systems on BCS-BEC crossover. By the properties of Besov, Sobolev spaces, and Fourier functions and the method of bootstrapping argument, we deduce that the global existence of strong solutions to time-dependent Ginzburg-Landau systems on BCS-BEC crossover in various spatial dimensions.

  3. Contributions to the mathematical study of BCS theory

    International Nuclear Information System (INIS)

    Deuchert, Andreas

    2016-01-01

    The results of this thesis contribute to the mathematical study of BCS theory, that is, to the study of the BCS gap equation and the BCS functional. In the first part, we investigate a recent definition of a generalized relative entropy for bounded and not necessarily compact operators, which, in the second part, is used to define and study a non-periodic version of the BCS functional with an external field. In the third part of this work, we consider the BCS functional in two spatial dimensions with a radial pair interaction and show that the translational symmetry of the model is not broken. The quantum relative entropy plays an important role in statistical mechanics and quantum information theory. Apart from its relevance in quantum physics, it has interesting mathematical properties, such as joint convexity and monotonicity. From a purely mathematical point of view, it can be interpreted as a distance measure between two matrices, or more generally two trace-class operators, A and B. Like Hartree states, BCS states are conveniently described in terms of a generalized one-particle density matrix and so it is no surprise that the need to extend the relative entropy to non-compact operators also plays a role in BCS theory. This was our initial motivation in studying this object. The generalized relative entropy of Lewin and Sabin is defined by a limiting procedure that resembles the thermodynamic limit. An important question left open in their work is whether there exists a simple formula that allows one to compute the limit without having to work with the complicated limiting procedure. Such a formula is necessary for example for trial state arguments. In Chapter 2 we answer this question affirmatively and derive such a formula. Assuming some mild regularity conditions for the operators A and B, we show that it takes a particularly simple form, which is suitable for computations. Our proof is based upon a novel integral representation of the generalized relative

  4. Contributions to the mathematical study of BCS theory

    Energy Technology Data Exchange (ETDEWEB)

    Deuchert, Andreas

    2016-09-29

    The results of this thesis contribute to the mathematical study of BCS theory, that is, to the study of the BCS gap equation and the BCS functional. In the first part, we investigate a recent definition of a generalized relative entropy for bounded and not necessarily compact operators, which, in the second part, is used to define and study a non-periodic version of the BCS functional with an external field. In the third part of this work, we consider the BCS functional in two spatial dimensions with a radial pair interaction and show that the translational symmetry of the model is not broken. The quantum relative entropy plays an important role in statistical mechanics and quantum information theory. Apart from its relevance in quantum physics, it has interesting mathematical properties, such as joint convexity and monotonicity. From a purely mathematical point of view, it can be interpreted as a distance measure between two matrices, or more generally two trace-class operators, A and B. Like Hartree states, BCS states are conveniently described in terms of a generalized one-particle density matrix and so it is no surprise that the need to extend the relative entropy to non-compact operators also plays a role in BCS theory. This was our initial motivation in studying this object. The generalized relative entropy of Lewin and Sabin is defined by a limiting procedure that resembles the thermodynamic limit. An important question left open in their work is whether there exists a simple formula that allows one to compute the limit without having to work with the complicated limiting procedure. Such a formula is necessary for example for trial state arguments. In Chapter 2 we answer this question affirmatively and derive such a formula. Assuming some mild regularity conditions for the operators A and B, we show that it takes a particularly simple form, which is suitable for computations. Our proof is based upon a novel integral representation of the generalized relative

  5. Interacting bosons model and relation with BCS theory

    International Nuclear Information System (INIS)

    Diniz, R.

    1990-01-01

    The Nambu mechanism for BCS theory is extended with inclusion of quadrupole pairing in addition to the usual monopole pairing. An effective Hamiltonian is constructed and its relation to the IBM is discussed. The faced difficulties and a possible generalization of this model are discussed. (author)

  6. Comparative study of BCS-BEC crossover theories above Tc: The nature of the pseudogap in ultracold atomic Fermi gases

    International Nuclear Information System (INIS)

    Chien, C.-C.; Guo Hao; He Yan; Levin, K.

    2010-01-01

    This article presents a comparison of two finite-temperature BCS-Bose-Einstein condensation (BEC) crossover theories above the transition temperature: Nozieres-Schmitt-Rink (NSR) theory and finite-T extended BCS-Leggett theory. The comparison is cast in the form of numerical studies of the behavior of the fermionic spectral function both theoretically and as constrained by (primarily) radio frequency (rf) experiments. Both theories include pair fluctuations and exhibit pseudogap effects, although the nature of this pseudogap is very different. The pseudogap in finite-T extended BCS-Leggett theory is found to follow a BCS-like dispersion which, in turn, is associated with a broadened BCS-like self-energy, rather more similar to what is observed in high-temperature superconductors (albeit, for a d-wave case). The fermionic quasiparticle dispersion is different in NSR theory and the damping is considerably larger. We argue that the two theories are appropriate in different temperature regimes with the BCS-Leggett approach being more suitable nearer to condensation. There should, in effect, be little difference at higher T as the pseudogap becomes weaker and where the simplifying approximations used in the BCS-Leggett approach break down. On the basis of momentum-integrated rf studies of unpolarized gases, it would be difficult to distinguish which theory is the better one. A full comparison for polarized gases is not possible since it is claimed that there are inconsistencies in the NSR approach (not found in the BCS-Leggett scheme). Future experiments along the lines of momentum-resolved experiments look to be very promising in distinguishing the two theories.

  7. BCS 50 years

    CERN Document Server

    Feldman, Dimitri

    2011-01-01

    The BCS theory of superconductivity developed in 1957 by Bardeen, Cooper and Schrieffer has been remarkably successful in explaining the properties of superconductors. In addition, concepts from BCS have been incorporated into diverse fields of physics, from nuclear physics and dense quark matter to the current standard model. Practical applications include SQUIDs, magnetic resonance imaging, superconducting electronics and the transmission of electricity. This invaluable book is a compilation of both a historical account and a discussion of the current state of theory and experiment. With con

  8. Role of superconducting energy gap in extended BCS-Bose crossover theory

    Science.gov (United States)

    Chávez, I.; García, L. A.; de Llano, M.; Grether, M.

    2017-10-01

    The generalized Bose-Einstein condensation (GBEC) theory of superconductivity (SC) is briefly surveyed. It hinges on three distinct new ingredients: (i) Treatment of Cooper pairs (CPs) as actual bosons since they obey Bose statistics, in contrast to BCS pairs which do not obey Bose commutation relations; (ii) inclusion of two-hole Cooper pairs (2hCPs) on an equal footing with two-electron Cooper pairs (2eCPs), thus making this a complete boson-fermion (BF) model; and (iii) inclusion in the resulting ternary ideal BF gas with particular BF vertex interactions that drive boson formation/disintegration processes. GBEC subsumes as special cases both BCS (having its 50-50 symmetry of both kinds of CPs) and ordinary BEC theories (having no 2hCPs), as well as the now familiar BCS-Bose crossover theory. We extended the crossover theory with the explicit inclusion of 2hCPs and construct a phase diagram of Tc/TF versus n/nf, where Tc and TF are the critical and Fermi temperatures, n is the total number density and nf that of unbound electrons at T = 0. Also, with this extended crossover one can construct the energy gap Δ(T)/Δ(0) versus T/Tc for some elemental SCs by solving at least two equations numerically: a gap-like and a number equation. In 50-50 symmetry, the energy gap curve agrees quite well with experimental data. But ignoring 2hCPs altogether leads to the gap curve falling substantially below that with 50-50 symmetry which already fits the data quite well, showing that 2hCPs are indispensable to describe SCs.

  9. Dynamical description of the fission process using the TD-BCS theory

    Energy Technology Data Exchange (ETDEWEB)

    Scamps, Guillaume, E-mail: scamps@nucl.phys.tohoku.ac.jp [Department of Physics, Tohoku University, Sendai 980-8578 (Japan); Simenel, Cédric [Department of Nuclear Physics, Research School of Physics and Engineering Australian National University, Canberra, Australian Capital Territory 2601 (Australia); Lacroix, Denis [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, F-91406 Orsay Cedex (France)

    2015-10-15

    The description of fission remains a challenge for nuclear microscopic theories. The time-dependent Hartree-Fock approach with BCS pairing is applied to study the last stage of the fission process. A good agreement is found for the one-body observables: the total kinetic energy and the average mass asymmetry. The non-physical dependence of two-body observables with the initial shape is discussed.

  10. Response Functions for the Two-Dimensional Ultracold Fermi Gas: Dynamical BCS Theory and Beyond

    Science.gov (United States)

    Vitali, Ettore; Shi, Hao; Qin, Mingpu; Zhang, Shiwei

    2017-12-01

    Response functions are central objects in physics. They provide crucial information about the behavior of physical systems, and they can be directly compared with scattering experiments involving particles such as neutrons or photons. Calculations of such functions starting from the many-body Hamiltonian of a physical system are challenging and extremely valuable. In this paper, we focus on the two-dimensional (2D) ultracold Fermi atomic gas which has been realized experimentally. We present an application of the dynamical BCS theory to obtain response functions for different regimes of interaction strengths in the 2D gas with zero-range attractive interaction. We also discuss auxiliary-field quantum Monte Carlo (AFQMC) methods for the calculation of imaginary time correlations in these dilute Fermi gas systems. Illustrative results are given and comparisons are made between AFQMC and dynamical BCS theory results to assess the accuracy of the latter.

  11. BCS wave function, matrix product states, and the Ising conformal field theory

    Science.gov (United States)

    Montes, Sebastián; Rodríguez-Laguna, Javier; Sierra, Germán

    2017-11-01

    We present a characterization of the many-body lattice wave functions obtained from the conformal blocks (CBs) of the Ising conformal field theory (CFT). The formalism is interpreted as a matrix product state using continuous ancillary degrees of freedom. We provide analytic and numerical evidence that the resulting states can be written as BCS states. We give a complete proof that the translationally invariant 1D configurations have a BCS form and we find suitable parent Hamiltonians. In particular, we prove that the ground state of the finite-size critical Ising transverse field (ITF) Hamiltonian can be obtained with this construction. Finally, we study 2D configurations using an operator product expansion (OPE) approximation. We associate these states to the weak pairing phase of the p +i p superconductor via the scaling of the pairing function and the entanglement spectrum.

  12. Relativistic BCS-BEC Crossover at Quark Level

    Directory of Open Access Journals (Sweden)

    Zhuang P.

    2010-10-01

    Full Text Available The non-relativistic G0G formalism of BCS-BEC crossover at finite temperature is extended to relativistic fermion systems. The theory recovers the BCS mean field approximation at zero temperature and the non-relativistic results in a proper limit. For massive fermions, when the coupling strength increases, there exist two crossovers from the weak coupling BCS superfluid to the non-relativistic BEC state and then to the relativistic BEC state. For color superconductivity at moderate baryon density, the matter is in the BCS-BEC crossover region, and the behavior of the pseudogap is quite similar to that found in high temperature superconductors.

  13. Further test of new pairing scheme used in overhaul of BCS theory

    International Nuclear Information System (INIS)

    Zheng, X.H.; Walmsley, D.G.

    2014-01-01

    Highlights: • Explanation of a new pairing scheme to overhaul BCS theory. • Prediction of superconductor properties from normal state resistivity. • Applications to Nb, Pb, Al, Ta, Mo, Ir and W, T c between 9.5 and 0.012 K. • High accuracy compared with measured energy gap of Nb, Pb, Al and Ta. • Prediction of energy gap for Mo, Ir and W (so far not measured). - Abstract: A new electron pairing scheme, rectifying a fundamental flaw of the BCS theory, is tested extensively. It postulates that superconductivity arises solely from residual umklapp scattering when it is not in competition for the same destination electron states with normal scattering. It reconciles a long standing theoretical discrepancy in the strength of the electron–phonon interaction between the normal and superconductive states. The new scheme is exploited to calculate the superconductive electron–phonon spectral density, α 2 F(ν), entirely on the basis of normal state electrical resistivity. This leads to first principles superconductive properties (zero temperature energy gap and tunnelling conductance) in seven metals which turn out to be highly accurate when compared with known data; in other cases experimental verification is invited. The transition temperatures involved vary over almost three orders of magnitude: from 9.5 K for niobium to 0.012 K for tungsten

  14. Polynomial Similarity Transformation Theory: A smooth interpolation between coupled cluster doubles and projected BCS applied to the reduced BCS Hamiltonian

    Energy Technology Data Exchange (ETDEWEB)

    Degroote, M. [Rice Univ., Houston, TX (United States); Henderson, T. M. [Rice Univ., Houston, TX (United States); Zhao, J. [Rice Univ., Houston, TX (United States); Dukelsky, J. [Consejo Superior de Investigaciones Cientificas (CSIC), Madrid (Spain). Inst. de Estructura de la Materia; Scuseria, G. E. [Rice Univ., Houston, TX (United States)

    2018-01-03

    We present a similarity transformation theory based on a polynomial form of a particle-hole pair excitation operator. In the weakly correlated limit, this polynomial becomes an exponential, leading to coupled cluster doubles. In the opposite strongly correlated limit, the polynomial becomes an extended Bessel expansion and yields the projected BCS wavefunction. In between, we interpolate using a single parameter. The e ective Hamiltonian is non-hermitian and this Polynomial Similarity Transformation Theory follows the philosophy of traditional coupled cluster, left projecting the transformed Hamiltonian onto subspaces of the Hilbert space in which the wave function variance is forced to be zero. Similarly, the interpolation parameter is obtained through minimizing the next residual in the projective hierarchy. We rationalize and demonstrate how and why coupled cluster doubles is ill suited to the strongly correlated limit whereas the Bessel expansion remains well behaved. The model provides accurate wave functions with energy errors that in its best variant are smaller than 1% across all interaction stengths. The numerical cost is polynomial in system size and the theory can be straightforwardly applied to any realistic Hamiltonian.

  15. Popov approximation for composite bosons in the BCS-BEC crossover

    International Nuclear Information System (INIS)

    Pieri, P.; Strinati, G.C.

    2005-01-01

    Theoretical treatments of the BCS-BEC crossover need to provide as accurate as possible descriptions of the two regimes where the diluteness condition applies, either in terms of the constituent fermions (BCS limit) or of the composite bosons which form as bound-fermion pairs (BEC limit). This has to occur via a single fermionic theory that bridges across these two limiting representations. In this paper, we set up successive improvements of the fermionic theory, that result into composite bosons described at the level of either the Bogoliubov or the Popov approximations for pointlike bosons. This work bears on the recent experimental advances on the BCS-BEC crossover with trapped Fermi atoms, which show the need for accurate theoretical descriptions of the BEC side of the crossover

  16. Relativistic BCS-BEC crossover at finite temperature and its application to color superconductivity

    International Nuclear Information System (INIS)

    He Lianyi; Zhuang Pengfei

    2007-01-01

    The nonrelativistic G 0 G formalism of BCS-BEC crossover at finite temperature is extended to relativistic fermion systems. The uncondensed pairs contribute a pseudogap to the fermion excitations. The theory recovers the BCS mean field approximation at zero temperature and the nonrelativistic results in a proper limit. For massive fermions, when the coupling strength increases, there exist two crossovers from the weak coupling BCS superfluid to the nonrelativistic BEC state and then to the relativistic BEC state. For color superconductivity at moderate baryon density, the matter is in the BCS-BEC crossover region, and the behavior of the pseudogap is quite similar to that found in high temperature superconductors

  17. BCS-BEC crossover in a system of microcavity polaritons

    International Nuclear Information System (INIS)

    Keeling, Jonathan; Eastham, P.R.; Szymanska, M.H.; Littlewood, P.B.

    2005-01-01

    We investigate the thermodynamics and signatures of a polariton condensate over a range of densities, using a model of microcavity polaritons with internal structure. We determine a phase diagram for this system including fluctuation corrections to the mean-field theory. At low densities the condensation temperature T c behaves like that for point bosons. At higher densities, when T c approaches the Rabi splitting, T c deviates from the form for point bosons, and instead approaches the result of a BCS-like mean-field theory. This crossover occurs at densities much less than the Mott density. We show that current experiments are in a density range where the phase boundary is described by the BCS-like mean-field boundary. We investigate the influence of inhomogeneous broadening and detuning of excitons on the phase diagram

  18. Banks-Casher-type relation for the BCS gap at high density

    OpenAIRE

    Kanazawa, Takuya; Wettig, Tilo; Yamamoto, Naoki

    2012-01-01

    We derive a new Banks-Casher-type relation which relates the density of complex Dirac eigenvalues at the origin to the BCS gap of quarks at high density. Our relation is applicable to QCD and QCD-like theories without a sign problem, such as two-color QCD and adjoint QCD with baryon chemical potential, and QCD with isospin chemical potential. It provides us with a method to measure the BCS gap through the Dirac spectrum on the lattice.

  19. Snake instability of dark solitons across the BEC-BCS crossover: An effective-field-theory perspective

    Science.gov (United States)

    Lombardi, G.; Van Alphen, W.; Klimin, S. N.; Tempere, J.

    2017-09-01

    In the present article the snake instability mechanism for dark solitons in superfluid Fermi gases is studied in the context of a recently developed effective field theory [S. N. Klimin et al., Eur. Phys. J. B 88, 122 (2015), 10.1140/epjb/e2015-60213-4]. This theoretical treatment has proven to be suitable to study stable dark solitons in quasi-one-dimensional setups across the BEC-BCS crossover. In this paper the nodal plane of the stable soliton solution is perturbed by adding a transverse modulation. The numerical solution of the system of coupled nonlinear differential equations describing the amplitude of the perturbation leads to an estimate of the growth rate and characteristic length scale of the instability, which are calculated for a wide range of interaction regimes and compared to other theoretical predictions. The behavior of the maximum transverse size that the atomic cloud can have in order to preserve the stability is described across the BEC-BCS crossover. The analysis of the effects of spin imbalance on this critical length reveals a stabilization of the soliton with increasing imbalance and therefore provides the experimental community with a method to achieve the realization of stable solitons in real three-dimensional configurations, without reducing the system dimensionality.

  20. Influence of the projection of BCS functions on the M1 and E2 transitions in rare earths

    International Nuclear Information System (INIS)

    Fellah, M.; Hammann, T.F.

    1975-01-01

    E2 and M1 transition probabilities for odd-mass rare earth nuclei, have been calculated using both the usual BCS wave functions and the strict particle conserving, projected BCS functions. The blocking effect has been exactly and systematically taken into account. The influence of the Coriolis interaction has been studied using the first order perturbation theory. Allowance has been made for the β and γ vibrations. The unphysical effects, due to particle fluctuation in the BCS theory, are not always negligible, but are in most cases, less important than the Coriolis effect [fr

  1. Brillouin-Wigner theory of mixed-valence impurities in BCS superconductor: Tc/TcO and ΔC/ΔCO

    International Nuclear Information System (INIS)

    Li Jun; Gong Changde.

    1986-08-01

    The (lowest order) Brillouin-Wigner perturbational expansion theory is adopted to describe the mixed-valence impurities in the BCS superconductor. Two substantial quantities characterizing the superconducting state, i.e. the reduced transition temperature T c /T cO and the reduced specific heat jump ΔC/ΔC O are calculated numerically as a function of the impurity concentration x and the energy level difference E f between two 4f configurations. A comparison with the experimental data of the Th 1-x Ce x and Th 1-x U x alloy is also included with a more reasonable fitting than Kaiser's theory. (author)

  2. Mathematical analysis of the multiband BCS gap equations in superconductivity

    Science.gov (United States)

    Yang, Yisong

    2005-01-01

    In this paper, we present a mathematical analysis for the phonon-dominated multiband isotropic and anisotropic BCS gap equations at any finite temperature T. We establish the existence of a critical temperature T so that, when TT, the only nonnegative gap solution is the zero solution, representing the normal phase. Furthermore, when T=T, we prove that the only gap solution is the zero solution and that the positive gap solution depend on the temperature TMarkowitz-Kadanoff model and we prove that the presence of anisotropic fluctuations enhances T as in the single-band case. A special consequence of these results is that the half-unity exponent isotope effect may rigorously be proved in the multiband BCS theory, isotropic or anisotropic.

  3. The BCS-BEC crossover: From ultra-cold Fermi gases to nuclear systems

    Science.gov (United States)

    Strinati, Giancarlo Calvanese; Pieri, Pierbiagio; Röpke, Gerd; Schuck, Peter; Urban, Michael

    2018-04-01

    This report addresses topics and questions of common interest in the fields of ultra-cold gases and nuclear physics in the context of the BCS-BEC crossover. By this crossover, the phenomena of Bardeen-Cooper-Schrieffer (BCS) superfluidity and Bose-Einstein condensation (BEC), which share the same kind of spontaneous symmetry breaking, are smoothly connected through the progressive reduction of the size of the fermion pairs involved as the fundamental entities in both phenomena. This size ranges, from large values when Cooper pairs are strongly overlapping in the BCS limit of a weak inter-particle attraction, to small values when composite bosons are non-overlapping in the BEC limit of a strong inter-particle attraction, across the intermediate unitarity limit where the size of the pairs is comparable with the average inter-particle distance. The BCS-BEC crossover has recently been realized experimentally, and essentially in all of its aspects, with ultra-cold Fermi gases. This realization, in turn, has raised the interest of the nuclear physics community in the crossover problem, since it represents an unprecedented tool to test fundamental and unanswered questions of nuclear many-body theory. Here, we focus on the several aspects of the BCS-BEC crossover, which are of broad joint interest to both ultra-cold Fermi gases and nuclear matter, and which will likely help to solve in the future some open problems in nuclear physics (concerning, for instance, neutron stars). Similarities and differences occurring in ultra-cold Fermi gases and nuclear matter will then be emphasized, not only about the relative phenomenologies but also about the theoretical approaches to be used in the two contexts. Common to both contexts is the fact that at zero temperature the BCS-BEC crossover can be described at the mean-field level with reasonable accuracy. At finite temperature, on the other hand, inclusion of pairing fluctuations beyond mean field represents an essential ingredient

  4. RMF+BCS description of N = 32 and N = 34 shell closure

    International Nuclear Information System (INIS)

    Saxena, G.; Kumawat, M.; Singh, U.K.; Jain, S.K.; Aggarwal, Mamta; Kaushik, M.; Singh, S. Somorendro

    2017-01-01

    We have employed RMF+BCS (relativistic mean-field plus BCS) approach to study N = 32 and N = 34 shell closure with the help of ground state properties of even-even nuclei. Our present investigations include single particle energies, deformations, separation energies as well as neutron and proton densities etc. Encouraged by the recent experiments showing neutron magicity at N = 32 for Ca isotopes, we have applied RMF theory with delta function pairing along with mass dependency (1/A) for full chain of N = 32 and N = 34 isotones upto drip lines. This study predicts new doubly magic nuclei specially 48 Si which is in the same mass region in 52 Ca as the recent experiments observed

  5. The BCS-BEC Crossover

    Science.gov (United States)

    Parish, Meera M.

    2015-09-01

    This chapter presents the crossover from the Bardeen-Cooper-Schrieffer (BCS) state of weakly correlated pairs of fermions to the Bose-Einstein condensation (BEC) of diatomic molecules in the atomic Fermi gas. Our aim is to provide a pedagogical review of the BCS-BEC crossover, with an emphasis on the basic concepts, particularly those that are not generally known or are difficult to find in the literature. We shall not attempt to give an exhaustive survey of current research in the limited space here; where possible, we will direct the reader to more extensive reviews.

  6. The biowaiver extension for BCS class III drugs: the effect of dissolution rate on the bioequivalence of BCS class III immediate-release drugs predicted by computer simulation.

    Science.gov (United States)

    Tsume, Yasuhiro; Amidon, Gordon L

    2010-08-02

    The Biopharmaceutical Classification System (BCS) guidance issued by the FDA allows waivers for in vivo bioavailability and bioequivalence studies for immediate-release (IR) solid oral dosage forms only for BCS class I drugs. However, a number of drugs within BCS class III have been proposed to be eligible for biowaivers. The World Health Organization (WHO) has shortened the requisite dissolution time of BCS class III drugs on their Essential Medicine List (EML) from 30 to 15 min for extended biowaivers; however, the impact of the shorter dissolution time on AUC(0-inf) and C(max) is unknown. The objectives of this investigation were to assess the ability of gastrointestinal simulation software to predict the oral absorption of the BCS class I drugs propranolol and metoprolol and the BCS class III drugs cimetidine, atenolol, and amoxicillin, and to perform in silico bioequivalence studies to assess the feasibility of extending biowaivers to BCS class III drugs. The drug absorption from the gastrointestinal tract was predicted using physicochemical and pharmacokinetic properties of test drugs provided by GastroPlus (version 6.0). Virtual trials with a 200 mL dose volume at different drug release rates (T(85%) = 15 to 180 min) were performed to predict the oral absorption (C(max) and AUC(0-inf)) of the above drugs. Both BCS class I drugs satisfied bioequivalence with regard to the release rates up to 120 min. The results with BCS class III drugs demonstrated bioequivalence using the prolonged release rate, T(85%) = 45 or 60 min, indicating that the dissolution standard for bioequivalence is dependent on the intestinal membrane permeability and permeability profile throughout the gastrointestinal tract. The results of GastroPlus simulations indicate that the dissolution rate of BCS class III drugs could be prolonged to the point where dissolution, rather than permeability, would control the overall absorption. For BCS class III drugs with intestinal absorption patterns

  7. Absence of coherent peaks in a Z2 fractionalized BCS superconducting state

    Science.gov (United States)

    Zhong, Yin; Lu, Han-Tao; Luo, Hong-Gang

    2015-01-01

    We explore a Z2 fractionalized Bardeen-Cooper-Schrieffer (BCS) superconducting state, which is a minimal extension of usual BCS framework. It is found that this state has similar thermal and transport properties, but its single-particle feature strongly deviates from the coherent quasiparticle behavior of the classic/conventional BCS superconducting state. The fingerprint of such Z2 BCS state is the absence of the BCS coherent peaks and instead a kink in the local density of state occurs, which in principle could be probed by scanning tunneling microscopy or point-contact spectroscopy experiments. The corresponding exactly soluble models that realize the desirable Z2 fractionalized BCS state are presented. In addition, we also study the extended t-U-J model by using Z2 slave-spin representation and find that the Z2 BCS state may exist when the paring structure is fully gapped or has nodes. The prototypical wave-function of such a Z2 BCS state is also proposed, which could be taken as trial wave-function in current numerical techniques. Furthermore, the pairing mechanism of Z2 BCS state is argued from both weak and strong coupling perspective. The present work may be helpful to further study the unconventional superconductivity and its relation to non-Fermi liquids.

  8. Dimensional BCS-BEC crossover in ultracold Fermi gases

    Energy Technology Data Exchange (ETDEWEB)

    Boettcher, Igor

    2014-12-10

    We investigate thermodynamics and phase structure of ultracold Fermi gases, which can be realized and measured in the laboratory with modern trapping techniques. We approach the subject from a both theoretical and experimental perspective. Central to the analysis is the systematic comparison of the BCS-BEC crossover of two-component fermions in both three and two dimensions. A dimensional reduction can be achieved in experiments by means of highly anisotropic traps. The Functional Renormalization Group (FRG) allows for a description of both cases in a unified theoretical framework. In three dimensions we discuss with the FRG the influence of high momentum particles onto the density, extend previous approaches to the Unitary Fermi Gas to reach quantitative precision, and study the breakdown of superfluidity due to an asymmetry in the population of the two fermion components. In this context we also investigate the stability of the Sarma phase. For the two-dimensional system scattering theory in reduced dimension plays an important role. We present both the theoretically as well as experimentally relevant aspects thereof. After a qualitative analysis of the phase diagram and the equation of state in two dimensions with the FRG we describe the experimental determination of the phase diagram of the two-dimensional BCS-BEC crossover in collaboration with the group of S. Jochim at PI Heidelberg.

  9. A Possible Path from BCS through HTS to VHTS

    Science.gov (United States)

    Chu, C. W.

    2010-03-01

    Three years after celebrating the 50th anniversary of the BCS theory and the 20th anniversary of the discovery of high temperature superconductivity (HTS), it appears to be most fitting for us to contemplate the possibility of very high temperature superconductivity (VHTS). VHTS, preferably at room temperature, if achieved, could change the world both scientifically and technologically. Unfortunately, it has long been considered by some to belong to the domain of science fiction and to occur only ``at an astronomical distance and under an astronomical pressure.'' With the advent of liquid nitrogen superconductivity in 1987, the outlook has become much brighter. Currently, there appears to be no reason, either theoretical or experimental, why VHTS would be impossible, in spite of the 2006 prediction of the death of HTS by 2010-2015 through the so-called scientometric analysis of the publication record of the previous 20 years. The recent discovery of the new class of Fe-pnictide HTSs fuels more cautious optimism. Since its inception, BCS theory has provided the basic framework for the occurrence and understanding of superconductivity, but it has failed to show where and how to find superconductivity at a higher temperature. This may be attributed to the small energy scale of superconductivity in comparison with those of other excitations in the solids. After examining existing data, we believe that a holistic multidisciplinary enlightened empirical approach appears to be the most effective way to discover novel superconductors with higher transition temperatures. In this talk, I shall present several possible approaches toward VHTS that we are currently pursuing, after briefly summarizing what has happened in the long search for HTS and VHTS.

  10. Detecting the BCS pairing amplitude via a sudden lattice ramp in a honeycomb lattice

    Science.gov (United States)

    Tiesinga, Eite; Nuske, Marlon; Mathey, Ludwig

    2016-05-01

    We determine the exact time evolution of an initial Bardeen-Cooper-Schrieffer (BCS) state of ultra-cold atoms in a hexagonal optical lattice. The dynamical evolution is triggered by ramping the lattice potential up, such that the interaction strength Uf is much larger than the hopping amplitude Jf. The quench initiates collective oscillations with frequency | Uf | /(2 π) in the momentum occupation numbers and imprints an oscillating phase with the same frequency on the order parameter Δ. The latter is not reproduced by treating the time evolution in mean-field theory. The momentum density-density or noise correlation functions oscillate at frequency | Uf | /(2 π) as well as its second harmonic. For a very deep lattice, with negligible tunneling energy, the oscillations of momentum occupation numbers are undamped. Non-zero tunneling after the quench leads to dephasing of the different momentum modes and a subsequent damping of the oscillations. This occurs even for a finite-temperature initial BCS state, but not for a non-interacting Fermi gas. We therefore propose to use this dephasing to detect a BCS state. Finally, we predict that the noise correlation functions in a honeycomb lattice will develop strong anti-correlations near the Dirac point. We acknowledge funding from the National Science Foundation.

  11. BCS equations in the continuum

    International Nuclear Information System (INIS)

    Sandulescu, N.; Liotta, R. J.; Wyss, R.

    1998-01-01

    The properties of nuclei close to the drip line are significantly influenced by the continuum part of the single-particle spectrum. The main role is played by the resonant states which are largely confined in the region of nuclear potential and therefore stronger coupled with the bound states in an excitation process. Resonant states are also important in the nuclei beyond the drip line. In this case the decay properties of the nucleus can be directly related to the widths of the narrow resonances occupied by the unbound nucleons. The aim of this work is to propose an alternative for evaluating the effect of the resonant part of single-particle spectrum on the pairing correlations calculated within the BCS approximation. We estimated the role of resonances in the case of the isotope 170 Sn. The Resonant-BCS (RBCS) equations are solved for the case of a seniority force. The BCS approximation based on a seniority force cannot be applied in the case of a nucleus immersed in a box if all discrete states simulating the continuum are considered. In such a case the pairing correlations will increase with the number of states in the box. In our case one can still apply a seniority force with RBCS because the effect of the continuum appears here through a finite number of physical resonances, well defined by the given mean field. Because these resonances have a spatial distribution concentrated within the region of the nuclear potential, one expects that the localization probability of nucleons, far out from the nuclear surface, to be small. The gap obtained taking correctly the contribution of resonances, according to RBCS equations, is about 1.3 MeV, while pairing gap calculated only with the bound single-particle spectrum has the value Δ = 1.10 MeV. If we introduce also the resonant states, neglecting completely their widths, the gap will increase to the value Δ = 1.880 MeV. Therefore, one cannot estimate properly the pairing correlations by supplementing the spectrum

  12. Inhomogeneous condensates in dilute nuclear matter and BCS-BEC crossovers

    International Nuclear Information System (INIS)

    Stein, Martin; Sedrakian, Armen; Huang, Xu-Guang; Clark, John W; Röpke, Gerd

    2014-01-01

    We report on recent progress in understanding pairing phenomena in low-density nuclear matter at small and moderate isospin asymmetry. A rich phase diagram has been found comprising various superfluid phases that include a homogeneous and phase-separated BEC phase of deuterons at low density and a homogeneous BCS phase, an inhomogeneous LOFF phase, and a phase-separated BCS phase at higher densities. The transition from the BEC phases to the BCS phases is characterized in terms of the evolution, from strong to weak coupling, of the condensate wavefunction and the second moment of its density distribution in r-space. We briefly discuss approaches to higher-order clustering in low-density nuclear matter.

  13. A two-dimensional Fermi gas in the BEC-BCS crossover

    Energy Technology Data Exchange (ETDEWEB)

    Ries, Martin Gerhard

    2016-01-21

    This thesis reports on the preparation of a 2D Fermi gas in the BEC-BCS crossover and the observation of the BKT transition into a quasi long-range ordered superfluid phase. The pair momentum distribution of the gas is probed by means of a matter-wave focusing technique which relies on time-of-flight evolution in a weak harmonic potential. This distribution holds the coherence properties of the gas. The quasi long-range ordered phase manifests itself as a sharp low-momentum peak. The temperature where it forms is identified as the transition temperature. By tuning the temperature and the interaction strength, the phase diagram of the 2D Fermi gas in the BEC-BCS crossover is mapped out. The phase coherence is investigated in a self-interference experiment. Furthermore, algebraic decay of correlations is observed in the trap average of the first order correlation function, which is obtained from the Fourier transform of the pair momentum distribution. This is in qualitative agreement with predictions of homogeneous theory for the superfluid phase in a 2D gas. The presented results provide a foundation for future experimental and theoretical studies of strongly correlated 2D Fermi gases. They might thus help to elucidate complex systems such as the electron gas in high-T{sub c} superconductors.

  14. Ground-state fidelity in the BCS-BEC crossover

    International Nuclear Information System (INIS)

    Khan, Ayan; Pieri, Pierbiagio

    2009-01-01

    The ground-state fidelity has been introduced recently as a tool to investigate quantum phase transitions. Here, we apply this concept in the context of a crossover problem. Specifically, we calculate the fidelity susceptibility for the BCS ground-state wave function, when the intensity of the fermionic attraction is varied from weak to strong in an interacting Fermi system, through the BCS-Bose-Einstein Condensation crossover. Results are presented for contact and finite-range attractive potentials and for both continuum and lattice models. We conclude that the fidelity susceptibility can be useful also in the context of crossover problems.

  15. Considerations for a Pediatric Biopharmaceutics Classification System (BCS): application to five drugs.

    Science.gov (United States)

    Gandhi, Shivani V; Rodriguez, William; Khan, Mansoor; Polli, James E

    2014-06-01

    It has been advocated that biopharmaceutic risk assessment should be conducted early in pediatric product development and synchronized with the adult product development program. However, we are unaware of efforts to classify drugs into a Biopharmaceutics Classification System (BCS) framework for pediatric patients. The objective was to classify five drugs into a potential BCS. These five drugs were selected since both oral and intravenous pharmacokinetic data were available for each drug, and covered the four BCS classes in adults. Literature searches for each drug were conducted using Medline and applied to classify drugs with respect to solubility and permeability in pediatric subpopulations. Four pediatric subpopulations were considered: neonates, infants, children, and adolescents. Regarding solubility, dose numbers were calculated using a volume for each subpopulation based on body surface area (BSA) relative to 250 ml for a 1.73 m(2) adult. Dose numbers spanned a range of values, depending upon the pediatric dose formula and subpopulation. Regarding permeability, pharmacokinetic literature data required assumptions and decisions about data collection. Using a devised pediatric BCS framework, there was agreement in adult and pediatric BCS class for two drugs, azithromycin (class 3) and ciprofloxacin (class 4). There was discordance for the three drugs that have high adult permeability since all pediatric permeabilities were low: dolasetron (class 3 in pediatric), ketoprofen (class 4 in pediatric), and voriconazole (class 4 in pediatric). A main contribution of this work is the identification of critical factors required for a pediatric BCS.

  16. THE BIOPHARMACEUTICAL CLASSIFICATION SYSTEM (BCS): PRESENT STATUS AND FUTURE PROSPECTIVES

    OpenAIRE

    Budhwaar Vikaas; Nanda Arun

    2012-01-01

    The Biopharmaceutical classification system (BCS) was introduced By Amidon et al., (1995) as a method for classifying drug substances based on their dose/solubility ratio and intestinal permeability. It allows predicting the in vivo pharmacokinetic performance of drug products. The drug can be categorized into four classes of BCS, namely, High solubility high permeability, low solubility high permeability, High solubility low permeability and low solubility low permeability. An objective of B...

  17. Prediction of solubility and permeability class membership: provisional BCS classification of the world's top oral drugs.

    Science.gov (United States)

    Dahan, Arik; Miller, Jonathan M; Amidon, Gordon L

    2009-12-01

    The Biopharmaceutics Classification System (BCS) categorizes drugs into one of four biopharmaceutical classes according to their water solubility and membrane permeability characteristics and broadly allows the prediction of the rate-limiting step in the intestinal absorption process following oral administration. Since its introduction in 1995, the BCS has generated remarkable impact on the global pharmaceutical sciences arena, in drug discovery, development, and regulation, and extensive validation/discussion/extension of the BCS is continuously published in the literature. The BCS has been effectively implanted by drug regulatory agencies around the world in setting bioavailability/bioequivalence standards for immediate-release (IR) oral drug product approval. In this review, we describe the BCS scientific framework and impact on regulatory practice of oral drug products and review the provisional BCS classification of the top drugs on the global market. The Biopharmaceutical Drug Disposition Classification System and its association with the BCS are discussed as well. One notable finding of the provisional BCS classification is that the clinical performance of the majority of approved IR oral drug products essential for human health can be assured with an in vitro dissolution test, rather than empirical in vivo human studies.

  18. A modified physiological BCS for prediction of intestinal absorption in drug discovery.

    Science.gov (United States)

    Zaki, Noha M; Artursson, Per; Bergström, Christel A S

    2010-10-04

    In this study, the influence of physiologically relevant media on the compound position in a biopharmaceutical classification system (BCS) which resembled the intestinal absorption was investigated. Both solubility and permeability limited compounds (n = 22) were included to analyze the importance of each of these on the final absorption. Solubility was determined in three different dissolution media, phosphate buffer pH 6.5 (PhB 6.5), fasted state simulated intestinal fluid (FaSSIF), and fed state simulated intestinal fluid (FeSSIF) at 37 °C, and permeability values were determined using the 2/4/A1 cell line. The solubility data and membrane permeability values were used for sorting the compounds into a BCS modified to reflect the fasted and fed state. Three of the seven compounds sorted as BCS II in PhB 6.5 (high permeability, low solubility) changed their position to BCS I when dissolved in FaSSIF and/or FeSSIF (high permeability, high solubility). These were low dosed (20 mg or less) lipophilic molecules displaying solvation limited solubility. In contrast, compounds having solid-state limited solubility had a minor increase in solubility when dissolved in FaSSIF and/or FeSSIF. Although further studies are needed to enable general cutoff values, our study indicates that low dosed BCS Class II compounds which have solubility normally restricted by poor solvation may behave as BCS Class I compounds in vivo. The large series of compounds investigated herein reveals the importance of investigating solubility and dissolution under physiologically relevant conditions in all stages of the drug discovery process to push suitable compounds forward, to select proper formulations, and to reduce the risk of food effects.

  19. Agitation Rate and Time for Complete Dissolution in BCS Biowaivers Based on Investigation of a BCS Biowaiver for Dexketoprofen Tablets.

    Science.gov (United States)

    Garcia-Arieta, Alfredo; Gordon, John; Gwaza, Luther; Mangas-Sanjuan, V; Álvarez, Covadonga; Torrado, Juan J

    2015-09-08

    The objective of the present work is to investigate the validity of the existing requirements for BCS biowaivers of immediate release products containing a class I drug in relation to the agitation rate (50 or 75 rpm in the paddle apparatus) and the time limit for complete dissolution (30 min) in the current biowaivers in vitro dissolution tests. Further, the possibility of extensions will be examined since it has been proposed that the time limit for complete dissolution should be revised to 60 min, and also, if cone formation occurs with apparatus 2 at 50 rpm, then a higher agitation rate is acceptable to eliminate it. The development of four generic dexketoprofen immediate release tablets is described. Dexketoprofen is the eutomer of ketoprofen. According to the BCS, dexketoprofen is a class I drug. Three out of the four products failed to show bioequivalence for Cmax in the initial bioequivalence study conducted with the product despite similar but nonrapid dissolution profiles at 50 rpm in the paddle apparatus, or similar and very rapid dissolution profiles at 75 rpm. In conclusion, these data indicate that BCS biowaivers for class I drugs should be granted only when dissolution with the paddle apparatus is complete in 30 min at 50 rpm. The time limit for complete dissolution should not be extended to 60 min. Furthermore, the agitation rate should not be increased to 75 rpm, even in the case of a coning effect.

  20. The complexity of intestinal permeability: Assigning the correct BCS classification through careful data interpretation.

    Science.gov (United States)

    Zur, Moran; Hanson, Allison S; Dahan, Arik

    2014-09-30

    While the solubility parameter is fairly straightforward when assigning BCS classification, the intestinal permeability (Peff) is more complex than generally recognized. In this paper we emphasize this complexity through the analysis of codeine, a commonly used antitussive/analgesic drug. Codeine was previously classified as a low-permeability compound, based on its lower LogP compared to metoprolol, a marker for the low-high permeability class boundary. In contrast, high fraction of dose absorbed (Fabs) was reported for codeine, which challenges the generally recognized Peff-Fabs correlation. The purpose of this study was to clarify this ambiguity through elucidation of codeine's BCS solubility/permeability class membership. Codeine's BCS solubility class was determined, and its intestinal permeability throughout the small intestine was investigated, both in vitro and in vivo in rats. Codeine was found to be unequivocally a high-solubility compound. All in vitro studies indicated that codeine's permeability is higher than metoprolol's. In vivo studies in rats showed similar permeability for both drugs throughout the entire small-intestine. In conclusion, codeine was found to be a BCS Class I compound. No Peff-Fabs discrepancy is involved in its absorption; rather, it reflects the risk of assigning BCS classification based on merely limited physicochemical characteristics. A thorough investigation using multiple experimental methods is prudent before assigning a BCS classification, to avoid misjudgment in various settings, e.g., drug discovery, formulation design, drug development and regulation. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Crossover between the dense electron-hole phase and the BCS excitonic phase in quantum dots

    International Nuclear Information System (INIS)

    Rodriguez, B.A.; Gonzalez, A.; Quiroga, L.; Capote, R.; Rodriguez, F.J.

    1999-09-01

    Second order perturbation theory and a Lipkin-Nogami scheme combined with an exact Monte Carlo projection after variation are applied to compute the ground-state energy of 6 ≤ N ≤ 210 electron-hole pairs confined in a parabolic two-dimensional quantum dot. The energy shows nice scaling properties as N or the confinement strength is varied. A crossover from the high-density electron-hole phase to the BCS excitonic phase is found at a density which is roughly four times the close-packing density of excitons. (author)

  2. Body condition score (BCS and metabolic status of shelter dogs

    Directory of Open Access Journals (Sweden)

    I. Andrighetto

    2010-04-01

    Full Text Available A group of 147 shelter dogs were weighted and assigned a body condition score (BCS using a 9 point scale system, in order to evaluate the prevalence of obesity in the kennel. More than 60% of the animals showed a BCS³6 (overweight and obese and this condition was mainly attributed to an excess of carbohydrates and fat in the diet. In 67/147 dogs, a blood sample was drawn and the effects of BCS, age and time spent in the shelter were evaluated on biochemical parameters. Obese dogs showed significantly higher levels of triglycerides (P<0.01, while increasing BCS determined only an increasing non significant trend on cholesterol values. Age influenced creatinine (P<0.05 and the oldest dogs scoring BCS³6 registered significant higher NEFA (P<0.05 and CK (P=0.01 levels. Time spent in the shelter did not affect any parameter. The dogs’ metabolic condition reflects the need of taking more care of the quality of feed administered in the shelters to avoid the negative health effects caused by chronic obesity.

  3. Twisting Anderson pseudospins with light: Quench dynamics in THz-pumped BCS superconductors

    Science.gov (United States)

    Chou, Yang-Zhi; Liao, Yunxiang; Foster, Matthew

    We study the preparation and the detection of coherent far-from-equilibrium BCS superconductor dynamics in THz pump-probe experiments. In a recent experiment, an intense monocycle THz pulse with center frequency ω = Δ was injected into a superconductor with BCS gap Δ the post-pump evolution was detected via the optical conductivity. It was argued that nonlinear coupling of the pump to the Anderson pseudospins of the superconductor induces coherent dynamics of the Higgs mode Δ (t) . We validate this picture in a 2D BCS model with a combination of exact numerics and the Lax reduction, and we compute the dynamical phase diagram. The main effect of the pump is to scramble the orientations of Anderson pseudospins along the Fermi surface by twisting them in the xy-plane. We show that more intense pulses can induce a far-from-equilibrium gapless phase (phase I), originally predicted in the context of interaction quenches. We show that the THz pump can reach phase I at much lower energy densities than an interaction quench, and we demonstrate that Lax reduction provides a quantitative tool for computing coherent BCS dynamics. We also compute the optical conductivity for the states discussed here.

  4. Twisting Anderson pseudospins with light: Quench dynamics in terahertz-pumped BCS superconductors

    Science.gov (United States)

    Chou, Yang-Zhi; Liao, Yunxiang; Foster, Matthew S.

    2017-03-01

    We study the preparation (pump) and the detection (probe) of far-from-equilibrium BCS superconductor dynamics in THz pump-probe experiments. In a recent experiment [R. Matsunaga, Y. I. Hamada, K. Makise, Y. Uzawa, H. Terai, Z. Wang, and R. Shimano, Phys. Rev. Lett. 111, 057002 (2013), 10.1103/PhysRevLett.111.057002], an intense monocycle THz pulse with center frequency ω ≃Δ was injected into a superconductor with BCS gap Δ ; the subsequent postpump evolution was detected via the optical conductivity. It was argued that nonlinear coupling of the pump to the Anderson pseudospins of the superconductor induces coherent dynamics of the Higgs (amplitude) mode Δ (t ) . We validate this picture in a two-dimensional BCS model with a combination of exact numerics and the Lax reduction method, and we compute the nonequilibrium phase diagram as a function of the pump intensity. The main effect of the pump is to scramble the orientations of Anderson pseudospins along the Fermi surface by twisting them in the x y plane. We show that more intense pump pulses can induce a far-from-equilibrium phase of gapless superconductivity ("phase I"), originally predicted in the context of interaction quenches in ultracold atoms. We show that the THz pump method can reach phase I at much lower energy densities than an interaction quench, and we demonstrate that Lax reduction (tied to the integrability of the BCS Hamiltonian) provides a general quantitative tool for computing coherent BCS dynamics. We also calculate the Mattis-Bardeen optical conductivity for the nonequilibrium states discussed here.

  5. Establishing the pharmaceutical quality of Chinese herbal medicine: a provisional BCS classification.

    Science.gov (United States)

    Fong, Sophia Y K; Liu, Mary; Wei, Hai; Löbenberg, Raimar; Kanfer, Isadore; Lee, Vincent H L; Amidon, Gordon L; Zuo, Zhong

    2013-05-06

    The Biopharmaceutical Classification System (BCS), which is a scientific approach to categorize active drug ingredient based on its solubility and intestinal permeability into one of the four classes, has been used to set the pharmaceutical quality standards for drug products in western society. However, it has received little attention in the area of Chinese herbal medicine (CHM). This is likely, in part, due to the presence of multiple active components as well as lack of standardization of CHM. In this report, we apply BCS classification to CHMs provisionally as a basis for establishing improved in vitro quality standards. Based on a top-200 drugs selling list in China, a total of 31 CHM products comprising 50 official active marker compounds (AMCs) were provisionally classified according to BCS. Information on AMC content and doses of these CHM products were retrieved from the Chinese Pharmacopoeia. BCS parameters including solubility and permeability of the AMCs were predicted in silico (ACD/Laboratories). A BCS classification of CHMs according to biopharmaceutical properties of their AMCs is demonstrated to be feasible in the current study and can be used to provide a minimum set of quality standards. Our provisional results showed that 44% of the included AMCs were classified as Class III (high solubility, low permeability), followed by Class II (26%), Class I (18%), and Class IV (12%). A similar trend was observed when CHMs were classified in accordance with the BCS class of AMCs. Most (45%) of the included CHMs were classified as Class III, followed by Class II (16%), Class I (10%), and Class IV (6%); whereas 23% of the CHMs were of mixed class due to the presence of multiple individual AMCs with different BCS classifications. Moreover, about 60% of the AMCs were classified as high-solubility compounds (Class I and Class III), suggesting an important role for an in vitro dissolution test in setting quality control standards ensuring consistent

  6. More on ghost condensation in Yang-Mills theory: BCS versus Overhauser effect and the breakdown of the Nakanishi-Ojima annex SL(2,R) symmetry

    International Nuclear Information System (INIS)

    Dudal, David; Verschelde, Henri; Lemes, Vitor E.R.; Sarandy, Marcelo S.; Sorella, Silvio P.; Picariello, Marco; Vicini, Alessandro; Gracey, John A.

    2003-01-01

    We analyze the ghost condensates abc c b c c >, abc c-bar b c-bar c > and abc c-barbc c > in Yang-Mills theory in the Curci-Ferrari gauge. By combining the local composite operator formalism with the algebraic renormalization technique, we are able to give a simultaneous discussion of abc c b c c >, abc c-bar b c-bar c > and abc c-bar b c c >, which can be seen as playing the role of the BCS, respectively Overhauser effect in ordinary superconductivity. The Curci-Ferrari gauge exhibits a global continuous symmetry generated by the Nakanishi-Ojima (NO) algebra. This algebra includes, next to the {(anti-)BRST} transformation, a SL(2,R) subalgebra. We discuss the dynamical symmetry breaking of the NO algebra through these ghost condensates. Particular attention is paid to the Landau gauge, a special case of the Curci-Ferrari gauge. (author)

  7. Ultracold lithium-6 atoms in the BEC-BCS crossover: experiments and the construction of a new apparatus; Atomes de lithium-6 ultra froids dans la transition BEC-BCS: experiences et construction d'un montage experimental

    Energy Technology Data Exchange (ETDEWEB)

    Teichmann, M

    2007-09-15

    We use a fermionic gas of Lithium-6 as a model system to study superfluidity. The limiting cases of superfluidity are Bose-Einstein condensation (BEC) and superconductivity, described by the theory by Bardeen, Cooper and Schrieffer (BCS). In Lithium-6 gases, we can explore the whole range between the two cases, known as the BEC-BCS crossover, using a Feshbach resonance. We study the change of the momentum distribution of the gas in this cross-over and compare to theoretical models. We also investigate the hydrodynamic expansion, characteristic for a superfluid gas. We observe a sudden change of the ellipticity of the gas close to the transition to the superfluid phase. Moreover, we localized heteronuclear Feshbach resonances between {sup 6}Li and {sup 7}Li. We are currently constructing a second generation of the experimental setup. An new laser system, based on high power laser diodes, was developed. Changes in the vacuum chamber, including a complete reconstruction of the Zeeman slower, have increased the atomic flux, allowing us to increase the repetition rate of our experiment. Modifications of the geometry of the magnetic traps lead to a higher number of trapped atoms. (author)

  8. RMF+BCS description of some traditional neutron magic isotones

    International Nuclear Information System (INIS)

    Saxena, G.; Singh, D.; Kaushik, M.

    2014-01-01

    The traditional neutron magic nuclei with N = 8, 20, 28, 50, 82 and 126, and those with neutron sub-magic number N = 40 are investigated within the relativistic mean-field plus BCS (RMF+BCS) approach. The results indicate appearance of new proton magic numbers as well as the disappearance of conventional magic numbers for nuclei with extreme isospin values. The calculated energies and densities do not indicate any tendency for the proton halo formations in any of the proton rich isotones due to Coulomb interaction and different single particle spectra. However, the potential barrier provided by the Coulomb interaction and that due to the centrifugal force may cause a long delay in the actual decay of proton rich nucleus resulting in the extended drip line. (authors)

  9. Description of C isotopes within RMF+BCS approach

    International Nuclear Information System (INIS)

    Saxena, G.; Singh, D.; Kaushik, M.

    2013-01-01

    In the present investigations we have employed relativistic mean-field plus BCS (RMF + BCS) approach to carry out a systematic study for the ground state properties of even-even C Isotopes. One of the prime reason of this study has been to look into the role of low lying states in neutron rich reason near neutron drip line. It is found that irrespective of whether any resonant state exists or not, the occupancy of weakly bound neutron single particle states having low orbital angular momentum, (l = 0 or 1), with a well spread wave function due to the absence or very small strength of centrifugal barrier, helps to cause the occurrence of nuclei with widely extended neutron density. Such nuclei are found to have characteristically very small two-neutron separation energy and large neutron rms radius akin to that observed in weakly bound systems.

  10. Theories of superconductivity (a few remarks)

    International Nuclear Information System (INIS)

    Ginzburg, V.L.

    1992-01-01

    The early history in the development of superconductivity. Idea of pairing, Schafroth and BCS types of theories. Some remarks on present state of the microscopical theory of high-temperature superconductors (HTSC). Mean field macroscopic theory of superconductivity and its specific features in HTSC. About generalized macroscopic theory applicable in critical region. Concluding remarks. (orig.)

  11. Superfluidity and BCS-BEC crossover of ultracold atomic Fermi gases in mixed dimensions

    Science.gov (United States)

    Zhang, Leifeng; Chen, Qijin

    Atomic Fermi gases have been under active investigation in the past decade. Here we study the superfluid and pairing phenomena of a two-component ultracold atomic Fermi gas in the presence of mixed dimensionality, in which one component is confined on a 1D optical lattice whereas the other is free in the 3D continuum. We assume a short-range pairing interaction and determine the superfluid transition temperature Tc and the phase diagram for the entire BCS-BEC crossover, using a pairing fluctuation theory which includes self-consistently the contributions of finite momentum pairs. We find that, as the lattice depth increases and the lattice spacing decreases, the behavior of Tc becomes very similar to that of a population imbalance Fermi gas in a simple 3D continuum. There is no superfluidity even at T = 0 below certain threshold of pairing strength in the BCS regime. Nonmonotonic Tc behavior and intermediate temperature superfluidity emerge, and for deep enough lattice, the Tc curve will split into two parts. Implications for experiment will be discussed. References: 1. Q.J. Chen, Ioan Kosztin, B. Janko, and K. Levin, Phys. Rev. B 59, 7083 (1999). 2. Chih-Chun Chien, Qijin Chen, Yan He, and K. Levin, Phys. Rev. Lett. 97, 090402(2006). Work supported by NSF of China and the National Basic Research Program of China.

  12. The pairing theory - its physical basis and its consequences

    International Nuclear Information System (INIS)

    Schrieffer, J.R.

    1992-01-01

    The key developments which set the scene for the microscopic theory of superconductivity are discussed and the physical reasoning which lead to the pairing theory is presented. Consequences of the BCS theory are reviewed. (orig.)

  13. Ultracold lithium-6 atoms in the BEC-BCS crossover: experiments and the construction of a new apparatus; Atomes de lithium-6 ultra froids dans la transition BEC-BCS: experiences et construction d'un montage experimental

    Energy Technology Data Exchange (ETDEWEB)

    Teichmann, M

    2007-09-15

    We use a fermionic gas of Lithium-6 as a model system to study superfluidity. The limiting cases of superfluidity are Bose-Einstein condensation (BEC) and superconductivity, described by the theory by Bardeen, Cooper and Schrieffer (BCS). In Lithium-6 gases, we can explore the whole range between the two cases, known as the BEC-BCS crossover, using a Feshbach resonance. We study the change of the momentum distribution of the gas in this cross-over and compare to theoretical models. We also investigate the hydrodynamic expansion, characteristic for a superfluid gas. We observe a sudden change of the ellipticity of the gas close to the transition to the superfluid phase. Moreover, we localized heteronuclear Feshbach resonances between {sup 6}Li and {sup 7}Li. We are currently constructing a second generation of the experimental setup. An new laser system, based on high power laser diodes, was developed. Changes in the vacuum chamber, including a complete reconstruction of the Zeeman slower, have increased the atomic flux, allowing us to increase the repetition rate of our experiment. Modifications of the geometry of the magnetic traps lead to a higher number of trapped atoms. (author)

  14. Twisting Anderson pseudospins with light: Quench dynamics in THz-pumped BCS superconductors

    OpenAIRE

    Chou, Yang-Zhi; Liao, Yunxiang; Foster, Matthew S.

    2016-01-01

    We study the preparation (pump) and the detection (probe) of far-from-equilibrium BCS superconductor dynamics in THz pump-probe experiments. In a recent experiment [R. Matsunaga, Y. I. Hamada, K. Makise, Y. Uzawa, H. Terai, Z. Wang, and R. Shimano, Phys. Rev. Lett. {\\bf 111}, 057002 (2013)], an intense monocycle THz pulse with center frequency $\\omega \\simeq \\Delta$ was injected into a superconductor with BCS gap $\\Delta$; the subsequent post-pump evolution was detected via the optical conduc...

  15. A simplified generator coordinate treatment with analytical projected-BCS solutions for isovector pairing collective motions

    International Nuclear Information System (INIS)

    Kyotoku, M.; Chen, H.T.

    1979-01-01

    Analytical expressions for the projected-BCS energies and reaction transition rates among the isovector pairing collective states are obtained by the recognition of symmetry properties in a class of BCS wave functions. As a consequence, a simplified generator coordinate treatment is suggested [pt

  16. Coherence factors beyond the BCS expressions—a derivation

    International Nuclear Information System (INIS)

    Gorohovsky, G; Bettelheim, E

    2014-01-01

    We present a derivation of a previously announced result for matrix elements between exact eigenstates of the pairing Hamiltonian. Our results, which generalize the well-known Bardeen–Cooper–Schrieffer (BCS) (Bardeen et al 1957 Phys. Rev. 108 1175; 1957 Phys. Rev. 106 162) expressions for what are known as ‘coherence factors’, are derived based on the Slavnov (1989 Theor. Math. Phys. 79 502) formula for overlaps between Bethe-ansatz states, thus making use of the known connection between the exact diagonalization of the BCS Hamiltonian, due to Richardson (1963 Phys. Lett. 3 277; 1964 Nucl. Phys. A 52 221), and the algebraic Bethe ansatz. The resulting formula has a compact form after a suitable parameterization of the energy plane. Although we apply our method here to the pairing Hamiltonian, it may be adjusted to study what is termed the ‘Sutherland limit’ (Sutherland 1995 Phys. Rev. Lett. 74 816) for exactly solvable models, namely where a macroscopic number of rapidities form a large string. (paper)

  17. BCS superconductivity for weakly coupled clusters

    International Nuclear Information System (INIS)

    Friedel, J.

    1992-01-01

    BCS superconductivity is expected to have fairly high critical temperatures when clusters of moderate sizes are weakly coupled to form a crystal. This remark extends to quasi zerodimensional cases, a remark initially made by Labbe for quasi one-dimensional ones and by Hirsch, Bok and Labbe for quasi twodimensional ones. Possible applications are envisaged for twodimensional clusters (fullerene) or threedimensional ones (metal clusters, Chevrel phases). Conditions for optimal applicability of the scheme are somewhat restricted. (orig.)

  18. The Effect of Excipients on the Permeability of BCS Class III Compounds and Implications for Biowaivers.

    Science.gov (United States)

    Parr, Alan; Hidalgo, Ismael J; Bode, Chris; Brown, William; Yazdanian, Mehran; Gonzalez, Mario A; Sagawa, Kazuko; Miller, Kevin; Jiang, Wenlei; Stippler, Erika S

    2016-01-01

    Currently, the FDA allows biowaivers for Class I (high solubility and high permeability) and Class III (high solubility and low permeability) compounds of the Biopharmaceutics Classification System (BCS). Scientific evidence should be provided to support biowaivers for BCS Class I and Class III (high solubility and low permeability) compounds. Data on the effects of excipients on drug permeability are needed to demonstrate that commonly used excipients do not affect the permeability of BCS Class III compounds, which would support the application of biowaivers to Class III compounds. This study was designed to generate such data by assessing the permeability of four BCS Class III compounds and one Class I compound in the presence and absence of five commonly used excipients. The permeability of each of the compounds was assessed, at three to five concentrations, with each excipient in two different models: Caco-2 cell monolayers, and in situ rat intestinal perfusion. No substantial increases in the permeability of any of the compounds were observed in the presence of any of the tested excipients in either of the models, with the exception of disruption of Caco-2 cell monolayer integrity by sodium lauryl sulfate at 0.1 mg/ml and higher. The results suggest that the absorption of these four BCS Class III compounds would not be greatly affected by the tested excipients. This may have implications in supporting biowaivers for BCS Class III compounds in general.

  19. The (confinement) structure of Yang-Mills-theories within a Bose-BCS-theory

    International Nuclear Information System (INIS)

    Schuette, D.

    1984-01-01

    It is the purpose of this talk to report on a first attempt to apply (non-perturbative) techniques of many-body theory to a field-theory of the Yang-Mills-type. The procedure is in principle analogous to lattice calculations: In order to make the field-theoretical hamiltonian a well-behaved operator in the Fock-space, a phasespace-cutoff is assumed for the definition of the field operators. The coupling constant g then becomes a function of this cutoff which is fixed by some physical property like a glue-ball mass. (orig./HSI)

  20. Entanglement between pairing and screening in the Gorkov-Melik-Barkhudarov correction to the critical temperature throughout the BCS-BEC crossover

    Science.gov (United States)

    Pisani, L.; Perali, A.; Pieri, P.; Strinati, G. Calvanese

    2018-01-01

    The problem of the theoretical description of the critical temperature Tc of a Fermi superfluid dates back to the work by Gorkov and Melik-Barkhudarov (GMB), who addressed it for a weakly coupled (dilute) superfluid in what would today be referred to as the (extreme) BCS (weak-coupling) limit of the BCS-BEC crossover. The point made in this context by GMB was that particle-particle (pairing) excitations, which are responsible for superfluidity to occur below Tc, and particle-hole excitations, which give rise to screening also in a normal system, get effectively disentangled from each other in the BCS limit, thus yielding a reduction by a factor of 2.2 of the value of Tc obtained when neglecting screening effects. Subsequent work on this topic, that was aimed at extending the original GMB argument away from the BCS limit with diagrammatic methods, has tout court kept this disentangling between pairing and screening throughout the BCS-BEC crossover, without realizing that the conditions for it to be valid are soon violated away from the BCS limit. Here, we reconsider this problem from a more general perspective and argue that pairing and screening are intrinsically entangled with each other along the whole BCS-BEC crossover but for the BCS limit considered by GMB, with the particle-hole excitations soon transmuting into particle-particle excitations away from this limit. We substantiate our argument by performing a detailed numerical calculation of the GMB diagrammatic contribution suitably extended to the whole BCS-BEC crossover, where the full wave-vector and frequency dependence occurring in the repeated in-medium two-particle scattering is duly taken into account. Our numerical calculations are tested against analytic results available in both the BCS and BEC limits, and the contribution of the GMB diagrammatic term to the scattering length of composite bosons in the BEC limit is highlighted. We calculate Tc throughout the BCS-BEC crossover and find that it

  1. Ultracold lithium-6 atoms in the BEC-BCS crossover: experiments and the construction of a new apparatus

    International Nuclear Information System (INIS)

    Teichmann, M.

    2007-09-01

    We use a fermionic gas of Lithium-6 as a model system to study superfluidity. The limiting cases of superfluidity are Bose-Einstein condensation (BEC) and superconductivity, described by the theory by Bardeen, Cooper and Schrieffer (BCS). In Lithium-6 gases, we can explore the whole range between the two cases, known as the BEC-BCS crossover, using a Feshbach resonance. We study the change of the momentum distribution of the gas in this cross-over and compare to theoretical models. We also investigate the hydrodynamic expansion, characteristic for a superfluid gas. We observe a sudden change of the ellipticity of the gas close to the transition to the superfluid phase. Moreover, we localized heteronuclear Feshbach resonances between 6 Li and 7 Li. We are currently constructing a second generation of the experimental setup. An new laser system, based on high power laser diodes, was developed. Changes in the vacuum chamber, including a complete reconstruction of the Zeeman slower, have increased the atomic flux, allowing us to increase the repetition rate of our experiment. Modifications of the geometry of the magnetic traps lead to a higher number of trapped atoms. (author)

  2. On Pokrovskii's anisotropic gap equations in superconductivity theory

    Science.gov (United States)

    Yang, Yisong

    2003-11-01

    An existence and uniqueness theorem for Pokrovskii's zero-temperature anisotropic gap equation is proved. Furthermore, it is shown that Pokrovskii's finite-temperature equation is inconsistent with the Bardeen-Cooper-Schrieffer (BCS) theory. A reformulation of the anisotropic gap equation is presented along the line of Pokrovskii and it is shown that the new equation is consistent with the BCS theory for the whole temperature range. As an application, the Markowitz-Kadanoff model for anisotropic superconductivity is considered and a rigorous proof of the half-integer-exponent isotope effect is obtained. Furthermore, a sharp estimate of the gap solution near the transition temperature is established.

  3. The Combination of GIS and Biphasic to Better Predict In Vivo Dissolution of BCS Class IIb Drugs, Ketoconazole and Raloxifene.

    Science.gov (United States)

    Tsume, Yasuhiro; Igawa, Naoto; Drelich, Adam J; Amidon, Gregory E; Amidon, Gordon L

    2018-01-01

    The formulation developments and the in vivo assessment of Biopharmaceutical Classification System (BCS) class II drugs are challenging due to their low solubility and high permeability in the human gastrointestinal (GI) tract. Since the GI environment influences the drug dissolution of BCS class II drugs, the human GI characteristics should be incorporated into the in vitro dissolution system to predict bioperformance of BCS class II drugs. An absorptive compartment may be important in dissolution apparatus for BCS class II drugs, especially for bases (BCS IIb) because of high permeability, precipitation, and supersaturation. Thus, the in vitro dissolution system with an absorptive compartment may help predicting the in vivo phenomena of BCS class II drugs better than compendial dissolution apparatuses. In this study, an absorptive compartment (a biphasic device) was introduced to a gastrointestinal simulator. This addition was evaluated if this in vitro system could improve the prediction of in vivo dissolution for BCS class IIb drugs, ketoconazole and raloxifene, and subsequent absorption. The gastrointestinal simulator is a practical in vivo predictive tool and exhibited an improved in vivo prediction utilizing the biphasic format and thus a better tool for evaluating the bioperformance of BCS class IIb drugs than compendial apparatuses. Copyright © 2018. Published by Elsevier Inc.

  4. A modified BCS theory of heavy fermion superconductivity

    International Nuclear Information System (INIS)

    Baral, P.C.; Rout, G.C.

    2012-01-01

    In this paper we derive an expression for the superconducting gap equation for U and Ce based heavy fermion (HF) systems within a modified weak coupling theory of superconductivity. The calculated gap equation presents a mixture of pairing amplitudes of two different quasi-particle bands α and β. These two gap equations are solved numerically and self-consistently within the cut-off energy which arises due to the Kondo energy. It is found that the energy dependence of the enhanced density of states for the HF systems clearly manifests itself in the theory and the Kondo energy naturally takes the role of cut-off energy (ω c ), as long as the effective cut-off energy is large in comparison with the Kondo energy. The numerical analysis confirms this result and shows that superconducting transition temperature is independent of effective cut-off energy employed within this approach. The temperature dependence of gap equations are studied by varying the model parameters like positions of f-level, hybridization and coupling constants of the HF systems. (author)

  5. Software testing an ISTQB-BCS certified tester foundation guide

    CERN Document Server

    Hambling, Brian; Samaroo, Angelina; Thompson, Geoff; Williams, Peter; Hambling, Brian

    2015-01-01

    This practical guide provides insight into software testing, explaining the basics of the testing process and how to perform effective tests. It provides an overview of different techniques and how to apply them. It is the best-selling official textbook of the ISTQB-BCS Certified Tester Foundation Level.

  6. Some theories of high temperature superconductivity

    International Nuclear Information System (INIS)

    Cohen, M.L.

    1990-01-01

    In this paper a brief review is given of some historical aspects of theoretical research on superconductivity including a discussion of BCS theory and some theoretical proposals for mechanisms which can cause superconductivity at high temperatures

  7. Particle–hole duality, integrability, and Russian doll BCS model

    Energy Technology Data Exchange (ETDEWEB)

    Bork, L.V. [Center for Fundamental and Applied Research, N. L. Dukhov All-Russia Research Institute of Automatics, 127055 Moscow (Russian Federation); Institute for Theoretical and Experimental Physics, 117218 Moscow (Russian Federation); Pogosov, W.V., E-mail: walter.pogosov@gmail.com [Center for Fundamental and Applied Research, N. L. Dukhov All-Russia Research Institute of Automatics, 127055 Moscow (Russian Federation); Institute for Theoretical and Applied Electrodynamics, Russian Academy of Sciences, 125412 Moscow (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700 (Russian Federation)

    2015-08-15

    We address a generalized Richardson model (Russian doll BCS model), which is characterized by the breaking of time-reversal symmetry. This model is known to be exactly solvable and integrable. We point out that the Russian doll BCS model, on the level of Hamiltonian, is also particle–hole symmetric. This implies that the same state can be expressed both in the particle and hole representations with two different sets of Bethe roots. We then derive exact relations between Bethe roots in the two representations, which can hardly be obtained staying on the level of Bethe equations. In a quasi-classical limit, similar identities for usual Richardson model, known from literature, are recovered from our results. We also show that these relations for Richardson roots take a remarkably simple form at half-filling and for a symmetric with respect to the middle of the interaction band distribution of one-body energy levels, since, in this special case, the rapidities in the particle and hole representations up to the translation satisfy the same system of equations.

  8. Phase diagram of dilute nuclear matter: Unconventional pairing and the BCS-BEC crossover

    Energy Technology Data Exchange (ETDEWEB)

    Stein, Martin; Sedrakian, Armen [Frankfurt Univ. (Germany). Inst. fuer Theoretische Physik

    2013-07-01

    We report on a comprehensive study of the phase structure of cold, dilute nuclear matter featuring a {sup 3}S{sub 1}-{sup 3}D{sub 1} condensate at non-zero isospin asymmetry, within wide ranges of temperatures and densities. We find a rich phase diagram comprising three superfluid phases, namely a LOFF phase, the ordinary BCS phase, and a heterogeneous, phase-separated BCS phase, with associated crossovers from the latter two phases to a homogeneous or phase-separated Bose-Einstein condensate of deuterons. The phase diagram contains two tri-critical points (one a Lifshitz point), which may degenerate into a single tetra-critical point for some degree of isospin asymmetry.

  9. Enhancement of crystallinity of cellulose produced by Escherichia coli through heterologous expression of bcsD gene from Gluconacetobacter xylinus.

    Science.gov (United States)

    Sajadi, Elaheh; Babaipour, Valiollah; Deldar, Ali Asghar; Yakhchali, Bagher; Fatemi, Seyed Safa-Ali

    2017-09-01

    To evaluate the crystallinity index of the cellulose produced by Escherichia coli Nissle 1917 after heterologous expression of the cellulose synthase subunit D (bcsD) gene of Gluconacetobacter xylinus BPR2001. The bcsD gene of G. xylinus BPR2001 was expressed in E. coli and its protein product was visualized using SDS-PAGE. FTIR analysis showed that the crystallinity index of the cellulose produced by the recombinants was 0.84, which is 17% more than that of the wild type strain. The increased crystallinity index was also confirmed by X-ray diffraction analysis. The cellulose content was not changed significantly after over-expressing the bcsD. The bcsD gene can improve the crystalline structure of the bacterial cellulose but there is not any significant difference between the amounts of cellulose produced by the recombinant and wild type E. coli Nissle 1917.

  10. Development of HANARO human factors management plan and evaluation of BCS display

    International Nuclear Information System (INIS)

    Oh, I. S.; Lee, J. W.; Lee, Y. H.

    2004-01-01

    In this study, human factors evaluation of BCS display design was performed. We adopted the suitability of design elements of BCS display as human factors evaluation measure. And, we also adopted guideline based evaluation, field survey and expert evaluation as evaluation method. The checklist was utilized for the evaluation, and the results of evaluation were well arranged in the evaluation format. We did not find out the HED (Human Engineering Discrepancy) impede safety of HANARO, except some necessary items to improve during short periods. We also provide some items of improvement for the enhancement of safety and operator's performance in the aspect of long periods. If the proposed improvement items were completely fulfilled, the more improved safety of HANARO will be secured

  11. Quantum critical scaling of fidelity in BCS-like model

    International Nuclear Information System (INIS)

    Adamski, Mariusz; Jedrzejewski, Janusz; Krokhmalskii, Taras

    2013-01-01

    We study scaling of the ground-state fidelity in neighborhoods of quantum critical points in a model of interacting spinful fermions—a BCS-like model. Due to the exact diagonalizability of the model, in one and higher dimensions, scaling of the ground-state fidelity can be analyzed numerically with great accuracy, not only for small systems but also for macroscopic ones, together with the crossover region between them. Additionally, in the one-dimensional case we have been able to derive a number of analytical formulas for fidelity and show that they accurately fit our numerical results; these results are reported in the paper. Besides regular critical points and their neighborhoods, where well-known scaling laws are obeyed, there is the multicritical point and critical points in its proximity where anomalous scaling behavior is found. We also consider scaling of fidelity in neighborhoods of critical points where fidelity oscillates strongly as the system size or the chemical potential is varied. Our results for a one-dimensional version of a BCS-like model are compared with those obtained recently by Rams and Damski in similar studies of a quantum spin chain—an anisotropic XY model in a transverse magnetic field. (paper)

  12. Relativistic mean field theory for deformed nuclei with pairing correlations

    International Nuclear Information System (INIS)

    Geng, Lisheng; Toki, Hiroshi; Sugimoto, Satoru; Meng, Jie

    2003-01-01

    We develop a relativistic mean field (RMF) description of deformed nuclei with pairing correlations in the BCS approximation. The treatment of the pairing correlations for nuclei whose Fermi surfaces are close to the threshold of unbound states needs special attention. With this in mind, we use a delta function interaction for the pairing interaction to pick up those states whose wave functions are concentrated in the nuclear region and employ the standard BCS approximation for the single-particle states obtained from the BMF theory with deformation. We apply the RMF + BCS method to the Zr isotopes and obtain a good description of the binding energies and the nuclear radii of nuclei from the proton drip line to the neutron drip line. (author)

  13. The Effect of Excipients on the Permeability of BCS Class III Compounds and Implications for Biowaivers

    OpenAIRE

    Parr, Alan; Hidalgo, Ismael J.; Bode, Chris; Brown, William; Yazdanian, Mehran; Gonzalez, Mario A.; Sagawa, Kazuko; Miller, Kevin; Jiang, Wenlei; Stippler, Erika S.

    2015-01-01

    Purpose Currently, the FDA allows biowaivers for Class I (high solubility and high permeability) and Class III (high solubility and low permeability) compounds of the Biopharmaceutics Classification System (BCS). Scientific evidence should be provided to support biowaivers for BCS Class I and Class III (high solubility and low permeability) compounds. Methods Data on the effects of excipients on drug permeability are needed to demonstrate that commonly used excipients do not affect the permea...

  14. BCS-BEC crossover in spatially modulated fermionic condensates

    International Nuclear Information System (INIS)

    Sedrakian, Armen

    2011-01-01

    Several novel multi-component fermionic condensates show universal behavior under imbalance in the number of fermionic species. Here I discuss their phase structure, thermodynamics, and the transition from the weak (BCS) to strong (BEC) coupling regime. The inhomogeneous superconducting phases are illustrated on the example of the Fulde-Ferrell phase which appears in the weak coupling regime, at low temperatures and large asymmetries. The inhomogeneous phases persist through the crossover up to (and possibly beyond) the transition to the strong coupling regime.

  15. BCS-BEC crossover in spatially modulated fermionic condensates

    Energy Technology Data Exchange (ETDEWEB)

    Sedrakian, Armen, E-mail: sedrakian@th.physik.uni-frankfurt.de [Institute for Theoretical Physics, J. W. Goethe-University, Max-von-Laue-Str. 1, 60438 Frankfurt am Main (Germany)

    2011-09-16

    Several novel multi-component fermionic condensates show universal behavior under imbalance in the number of fermionic species. Here I discuss their phase structure, thermodynamics, and the transition from the weak (BCS) to strong (BEC) coupling regime. The inhomogeneous superconducting phases are illustrated on the example of the Fulde-Ferrell phase which appears in the weak coupling regime, at low temperatures and large asymmetries. The inhomogeneous phases persist through the crossover up to (and possibly beyond) the transition to the strong coupling regime.

  16. History of the theory of superconductivity

    International Nuclear Information System (INIS)

    Frohlich, H.

    1983-01-01

    This chapter points out that in the years from Onnes' discovery that the electric resistivity of mercury completely disappeared at about 4K in 1911 up to 1950, many attempts to develop a theory of superconductivity failed, and the subject became an outstanding problem in physics. Discusses the introduction of field theory into solid state physics, which proved to be the decisive step toward a theory. Describes how Schrieffer's suggestion of a wave function for the multielectron problem in terms of electron pairs led to the theory of superconductivity, or the so called B.C.S. theory

  17. Current and evolving approaches for improving the oral permeability of BCS Class III or analogous molecules.

    Science.gov (United States)

    Dave, Vivek S; Gupta, Deepak; Yu, Monica; Nguyen, Phuong; Varghese Gupta, Sheeba

    2017-02-01

    The Biopharmaceutics Classification System (BCS) classifies pharmaceutical compounds based on their aqueous solubility and intestinal permeability. The BCS Class III compounds are hydrophilic molecules (high aqueous solubility) with low permeability across the biological membranes. While these compounds are pharmacologically effective, poor absorption due to low permeability becomes the rate-limiting step in achieving adequate bioavailability. Several approaches have been explored and utilized for improving the permeability profiles of these compounds. The approaches include traditional methods such as prodrugs, permeation enhancers, ion-pairing, etc., as well as relatively modern approaches such as nanoencapsulation and nanosizing. The most recent approaches include a combination/hybridization of one or more traditional approaches to improve drug permeability. While some of these approaches have been extremely successful, i.e. drug products utilizing the approach have progressed through the USFDA approval for marketing; others require further investigation to be applicable. This article discusses the commonly studied approaches for improving the permeability of BCS Class III compounds.

  18. Theory of superconductivity. II. Excited Cooper pairs. Why does sodium remain normal down to 0 K?

    International Nuclear Information System (INIS)

    Fujita, S.

    1992-01-01

    Based on a generalized BCS Hamiltonian in which the interaction strengths (V 11 , V 22 , V 12 ) among and between electron (12) and hole (2) Cooper pairs are differentiated, the thermodynamic properties of a type-I superconductor below the critical temperature T c are investigated. An expression for the ground-state energy, W - W 0 , relative to the unperturbed Block system is obtained. The usual BCS formulas are obtained in the limits: (all) V jl = V 0 , N 1 (0) = N 2 (0). Any excitations generated through the BCS interaction Hamiltonian containing V jl must involve Cooper pairs of antiparallel spins and nearly opposite momenta. The nonzero momentum or excited Cooper pairs below T c are shown to have an excitation energy band minimum lower than the quasi-electrons, which were regarded as the elementary excitations in the original BCS theory. The energy gap var-epsilon g (T) defined relative to excited and zero-momentum Copper pairs (when V jl > 0) decreases from var-epsilon g (0) to 0 as the temperature T is raised from 0 to T c . If electrons only are available as in a monovalent metal like sodium (V 12 = 0), the energy constant Δ 1 is finite but the energy gap vanishes identically for all T. In agreement with the BCS theory, the present theory predicts that a pure nonmagnetic metal in any dimensions should have a Cooper-pair ground state whose energy is lower than that of the Bloch ground state. Additionally it predicts that a monovalent metal should remain normal down to 0 K, and that there should be no strictly one-dimensional superconductor

  19. BEC-BCS crossover in a (p+ip)-wave pairing Hamiltonian coupled to bosonic molecular pairs

    International Nuclear Information System (INIS)

    Dunning, Clare; Isaac, Phillip S.; Links, Jon; Zhao, Shao-You

    2011-01-01

    We analyse a (p+ip)-wave pairing BCS Hamiltonian, coupled to a single bosonic degree of freedom representing a molecular condensate, and investigate the nature of the BEC-BCS crossover for this system. For a suitable restriction on the coupling parameters, we show that the model is integrable and we derive the exact solution by the algebraic Bethe ansatz. In this manner we also obtain explicit formulae for correlation functions and compute these for several cases. We find that the crossover between the BEC state and the strong pairing p+ip phase is smooth for this model, with no intermediate quantum phase transition.

  20. The energetic state of mitochondria modulates complex III biogenesis through the ATP-dependent activity of Bcs1.

    Science.gov (United States)

    Ostojić, Jelena; Panozzo, Cristina; Lasserre, Jean-Paul; Nouet, Cécile; Courtin, Florence; Blancard, Corinne; di Rago, Jean-Paul; Dujardin, Geneviève

    2013-10-01

    Our understanding of the mechanisms involved in mitochondrial biogenesis has continuously expanded during the last decades, yet little is known about how they are modulated to optimize the functioning of mitochondria. Here, we show that mutations in the ATP binding domain of Bcs1, a chaperone involved in the assembly of complex III, can be rescued by mutations that decrease the ATP hydrolytic activity of the ATP synthase. Our results reveal a Bcs1-mediated control loop in which the biogenesis of complex III is modulated by the energy-transducing activity of mitochondria. Although ATP is well known as a regulator of a number of cellular activities, we show here that ATP can be also used to modulate the biogenesis of an enzyme by controlling a specific chaperone involved in its assembly. Our study further highlights the intramitochondrial adenine nucleotide pool as a potential target for the treatment of Bcs1-based disorders. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. In silico prediction of drug dissolution and absorption with variation in intestinal pH for BCS class II weak acid drugs: ibuprofen and ketoprofen.

    Science.gov (United States)

    Tsume, Yasuhiro; Langguth, Peter; Garcia-Arieta, Alfredo; Amidon, Gordon L

    2012-10-01

    The FDA Biopharmaceutical Classification System guidance allows waivers for in vivo bioavailability and bioequivalence studies for immediate-release solid oral dosage forms only for BCS class I. Extensions of the in vivo biowaiver for a number of drugs in BCS class III and BCS class II have been proposed, in particular, BCS class II weak acids. However, a discrepancy between the in vivo BE results and in vitro dissolution results for BCS class II acids was recently observed. The objectives of this study were to determine the oral absorption of BCS class II weak acids via simulation software and to determine if the in vitro dissolution test with various dissolution media could be sufficient for in vitro bioequivalence studies of ibuprofen and ketoprofen as models of carboxylic acid drugs. The oral absorption of these BCS class II acids from the gastrointestinal tract was predicted by GastroPlus™. Ibuprofen did not satisfy the bioequivalence criteria at lower settings of intestinal pH of 6.0. Further the experimental dissolution of ibuprofen tablets in a low concentration phosphate buffer at pH 6.0 (the average buffer capacity 2.2 mmol l (-1) /pH) was dramatically reduced compared with the dissolution in SIF (the average buffer capacity 12.6 mmol l (-1) /pH). Thus these predictions for the oral absorption of BCS class II acids indicate that the absorption patterns depend largely on the intestinal pH and buffer strength and must be considered carefully for a bioequivalence test. Simulation software may be a very useful tool to aid the selection of dissolution media that may be useful in setting an in vitro bioequivalence dissolution standard. Copyright © 2012 John Wiley & Sons, Ltd.

  2. S-pairing in neutron matter: I. Correlated basis function theory

    International Nuclear Information System (INIS)

    Fabrocini, Adelchi; Fantoni, Stefano; Illarionov, Alexey Yu.; Schmidt, Kevin E.

    2008-01-01

    S-wave pairing in neutron matter is studied within an extension of correlated basis function (CBF) theory to include the strong, short range spatial correlations due to realistic nuclear forces and the pairing correlations of the Bardeen, Cooper and Schrieffer (BCS) approach. The correlation operator contains central as well as tensor components. The correlated BCS scheme of [S. Fantoni, Nucl. Phys. A 363 (1981) 381], developed for simple scalar correlations, is generalized to this more realistic case. The energy of the correlated pair condensed phase of neutron matter is evaluated at the two-body order of the cluster expansion, but considering the one-body density and the corresponding energy vertex corrections at the first order of the Power Series expansion. Based on these approximations, we have derived a system of Euler equations for the correlation factors and for the BCS amplitudes, resulting in correlated nonlinear gap equations, formally close to the standard BCS ones. These equations have been solved for the momentum independent part of several realistic potentials (Reid, Argonne v 14 and Argonne v 8 ' ) to stress the role of the tensor correlations and of the many-body effects. Simple Jastrow correlations and/or the lack of the density corrections enhance the gap with respect to uncorrelated BCS, whereas it is reduced according to the strength of the tensor interaction and following the inclusion of many-body contributions

  3. Cosmological BCS mechanism and the big bang singularity

    Science.gov (United States)

    Alexander, Stephon; Biswas, Tirthabir

    2009-07-01

    We provide a novel mechanism that resolves the big bang singularity present in Friedman-Lemaitre-Robertson-Walker space-times without the need for ghost fields. Building on the fact that a four-fermion interaction arises in general relativity when fermions are covariantly coupled, we show that at early times the decrease in scale factor enhances the correlation between pairs of fermions. This enhancement leads to a BCS-like condensation of the fermions and opens a gap dynamically driving the Hubble parameter H to zero and results in a nonsingular bounce, at least in some special cases.

  4. In Silico Prediction of Drug Dissolution and Absorption with variation in Intestinal pH for BCS Class II Weak Acid Drugs: Ibuprofen and Ketoprofen§

    Science.gov (United States)

    Tsume, Yasuhiro; Langguth, Peter; Garcia-Arieta, Alfredo; Amidon, Gordon L.

    2012-01-01

    The FDA Biopharmaceutical Classification System guidance allows waivers for in vivo bioavailability and bioequivalence studies for immediate-release solid oral dosage forms only for BCS class I. Extensions of the in vivo biowaiver for a number of drugs in BCS Class III and BCS class II have been proposed, particularly, BCS class II weak acids. However, a discrepancy between the in vivo- BE results and in vitro- dissolution results for a BCS class II acids was recently observed. The objectives of this study were to determine the oral absorption of BCS class II weak acids via simulation software and to determine if the in vitro dissolution test with various dissolution media could be sufficient for in vitro bioequivalence studies of ibuprofen and ketoprofen as models of carboxylic acid drugs. The oral absorption of these BCS class II acids from the gastrointestinal tract was predicted by GastroPlus™. Ibuprofen did not satisfy the bioequivalence criteria at lower settings of intestinal pH=6.0. Further the experimental dissolution of ibuprofen tablets in the low concentration phosphate buffer at pH 6.0 (the average buffer capacity 2.2 mmol L-1/pH) was dramatically reduced compared to the dissolution in SIF (the average buffer capacity 12.6 mmol L -1/pH). Thus these predictions for oral absorption of BCS class II acids indicate that the absorption patterns largely depend on the intestinal pH and buffer strength and must be carefully considered for a bioequivalence test. Simulation software may be very useful tool to aid the selection of dissolution media that may be useful in setting an in vitro bioequivalence dissolution standard. PMID:22815122

  5. Effective theory of bosonic superfluids

    International Nuclear Information System (INIS)

    Schakel, A.M.J.

    1994-01-01

    The authors discuss the effective theory of a bosonic superfluid whose microscopic behavior is described by a nonrelativistic, weak-coupling φ 4 theory in the phase with broken particle number symmetry, both at zero temperature and in the vicinity of the phase transition. In the zero-temperature regime, the theory is governed by the gapless Goldstone mode resulting from the broken symmetry. Although this mode is gapless, the effective theory turns out to be Gallilei invariant. The regime just below the critical temperature is approached in a high-temperature expansion which is shown to be consistent with the weak-coupling assumption of the theory. The authors calculate the critical temperature, the coefficients of the Landau theory, and the finite-temperature sound velocity. A comparison with BCS theory is given

  6. BCS @ 50: derivation of gap equations in different lattice geometries

    International Nuclear Information System (INIS)

    Saurabh Basu

    2007-07-01

    We rigorously derive BCS gap equations for a square, triangular and a honeycomb lattice using a two-dimensional t-J model. The gap equations in all the three lattice geometries look usual, with band indices appearing and a minor modification in the separable pair potential for the (two band) honeycomb lattice. In each case, the gap equation is solved (self consistently with the number equation) at low densities assuming singlet pairing. (author)

  7. Research in the theory of condensed matter and elementary particles. [Progress report

    International Nuclear Information System (INIS)

    1985-01-01

    The proposed research is concerned with problems occupying the common ground between quantum field theory and statistical mechanics. The topics under investigation include: superconformal field theory in two dimensions, its relationship to two dimensional critical phenomena and its applications in string theory; the covariant formulation of the superstring theory; formation of large-scale structures and spatial chaos in dynamical systems; fermion-boson mass relations in BCS type theories; and properties of quantum field theories defined over galois fields. 37 refs

  8. Quantifying the Chasm: Exploring the Impact of the BCS on Total Football Revenues for Division One Football Programs from 2002-2012

    Science.gov (United States)

    Caro, Cary A.

    2014-01-01

    The Bowl Championship Series served as a collection of bowl games that were designed to crown the national champion in Division One football. The BCS created two classifications of institutions in Division football, those that were granted automatic access (AQ) to the post-season games, and those that were not (non-AQ). The BCS also generated…

  9. Regional-dependent intestinal permeability and BCS classification: elucidation of pH-related complexity in rats using pseudoephedrine.

    Science.gov (United States)

    Fairstein, Moran; Swissa, Rotem; Dahan, Arik

    2013-04-01

    Based on its lower Log P value relative to metoprolol, a marker for the low/high-permeability (P(eff)) class boundary, pseudoephedrine was provisionally classified as BCS low-permeability compound. On the other hand, following oral administration, pseudoephedrine fraction dose absorbed (F(abs)) and systemic bioavailability approaches 100%. This represents a challenge to the generally recognized P(eff)-F(abs) correlation. The purpose of this study was to elucidate the underlying mechanisms behind the confusion in pseudoephedrine's BCS classification. Pseudoephedrine's BCS solubility class was determined, and its physicochemical properties and intestinal permeability were thoroughly investigated, both in vitro and in vivo in rats, considering the complexity of the whole of the small intestine. Pseudoephedrine was found to be unequivocally a high-solubility compound. All of the permeability studies revealed similar phenomenon; at any given intestinal segment/pH, the permeability of metoprolol was higher than that of pseudoephedrine, however, as the intestinal region becomes progressively distal, and the pH gradually increases, pseudoephedrine's permeability rises above that of metoprolol in the former segment. This unique permeability pattern likely explains pseudoephedrine's complete absorption. In conclusion, pseudoephedrine is a BCS Class I compound; no discrepancy between P(eff) and F(abs) is involved in its absorption. Rather, it reflects the complexity behind P(eff) when considering the whole of the intestine. We propose to allow high-permeability classification to drugs with P(eff) that matches/exceeds the low/high class benchmark anywhere throughout the intestinal tract and not restricted necessarily to the jejunum.

  10. Gravitationally bound BCS state as dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, Stephon [Department of Physics, Brown University, Providence, RI 20912 (United States); Cormack, Sam, E-mail: stephon_alexander@brown.edu, E-mail: samuel.c.cormack.gr@dartmouth.edu [Department of Physics and Astronomy, Dartmouth College, Hanover, NH 03755 (United States)

    2017-04-01

    We explore the possibility that fermionic dark matter undergoes a BCS transition to form a superfluid. This requires an attractive interaction between fermions and we describe a possible source of this interaction induced by torsion. We describe the gravitating fermion system with the Bogoliubov-de Gennes formalism in the local density approximation. We solve the Poisson equation along with the equations for the density and gap energy of the fermions to find a self-gravitating, superfluid solution for dark matter halos. In order to produce halos the size of dwarf galaxies, we require a particle mass of ∼ 200 eV. We find a maximum attractive coupling strength before the halo becomes unstable. If dark matter halos do have a superfluid component, this raises the possibility that they contain vortex lines.

  11. Non-BCS superconductivity for underdoped cuprates by spin-vortex attraction

    OpenAIRE

    Marchetti, P. A.; Ye, F.; Su, Z. B.; Yu, L.

    2011-01-01

    Within a gauge approach to the t-J model, we propose a new, non-BCS mechanism of superconductivity for underdoped cuprates. The gluing force of the superconducting mechanism is an attraction between spin vortices on two different N\\'eel sublattices, centered around the empty sites described in terms of fermionic holons. The spin fluctuations are described by bosonic spinons with a gap generated by the spin vortices. Due to the no-double occupation constraint, there is a gauge attraction betwe...

  12. Bcs1p can rescue a large and productive cytochrome bc(1) complex assembly intermediate in the inner membrane of yeast mitochondria.

    Science.gov (United States)

    Conte, Laura; Trumpower, Bernard L; Zara, Vincenzo

    2011-01-01

    The yeast cytochrome bc(1) complex, a component of the mitochondrial respiratory chain, is composed of ten distinct protein subunits. In the assembly of the bc(1) complex, some ancillary proteins, such as the chaperone Bcs1p, are actively involved. The deletion of the nuclear gene encoding this chaperone caused the arrest of the bc(1) assembly and the formation of a functionally inactive bc(1) core structure of about 500-kDa. This immature bc(1) core structure could represent, on the one hand, a true assembly intermediate or, on the other hand, a degradation product and/or an incorrect product of assembly. The experiments here reported show that the gradual expression of Bcs1p in the yeast strain lacking this protein was progressively able to rescue the bc(1) core structure leading to the formation of the functional homodimeric bc(1) complex. Following Bcs1p expression, the mature bc(1) complex was also progressively converted into two supercomplexes with the cytochrome c oxidase complex. The capability of restoring the bc(1) complex and the supercomplexes was also possessed by the mutated yeast R81C Bcsp1. Notably, in the human ortholog BCS1L, the corresponding point mutation (R45C) was instead the cause of a severe bc(1) complex deficiency. Differently from the yeast R81C Bcs1p, two other mutated Bcs1p's (K192P and F401I) were unable to recover the bc(1) core structure in yeast. This study identifies for the first time a productive assembly intermediate of the yeast bc(1) complex and gives new insights into the molecular mechanisms involved in the last steps of bc(1) assembly. Copyright © 2010 Elsevier B.V. All rights reserved.

  13. San Juanico, BCS, Mexico, hybrid electric plant renewable energies in the rural communities development; Planta electrica hibrida San Juanico, B.C.S., Mexico, las energias renovables en el desarrollo de las comunidades rurales

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Rios, Serafin [Gerencia de Proyectos Geotermoelectricos, Comision Federal de Electricidad (Mexico)

    1999-08-01

    The hybrid electric plant of San Juanico, B.C.S., Mexico, is described in terms of its environmental goals, operating process and contribution to the development of that rural community of the Baja California Peninsula. San Juanico hybrid electric plant is organized in three electrical generation systems that work in parallel: one uses solar energy, another wind energy and a third one uses diesel fuel. [Spanish] Se describe la planta hibrida de San Juanico, BCS, Mexico, en terminos de los objetivos ambientales que condujeron a su realizacion, asi como de su proceso operativo y de la participacion que tiene en el desarrollo de esa comunidad rural de la peninsula de Baja California, Mexico. La planta hibrida de San Juanico esta constituida por tres sistemas de generacion de electrcicidad que operan en paralelo: uno utiliza energia radiante del sol, otro energia del viento y un tercero utiliza diesel.

  14. Cultura, identidad política y multiculturalidad en Todos Santos, BCS1

    Directory of Open Access Journals (Sweden)

    Rossana Almada

    2005-01-01

    Full Text Available Este ensayo tiene como objetivo hablar del desbordamiento institucional de la política y su desplazamiento hacia la sociedad civil. Desde luego, no es la intención negar la importancia de instituciones políticas tales como partidos, sino señalar cómo la morfología de la complejidad social desdibuja las fronteras de la representación y traslada las demandas a las calles, a las cantinas,a las casas de los interesados. El trabajo forma parte de una investigación mayor a la que he llamado Juntos, pero no revueltos. Multiculturalidad e identidad local en Todos Santos, BCS, es por eso que presento como ejemplo de este fenómeno el caso del conflicto latente en Todos Santos, Baja California Sur (BCS tanto por el uso de los espacios como por las formas que tendrá que adquirir la identidad local que construyen, a partir de sus convergencias y negociaciones, los tres grupos en lucha por la hegemonía social todosanteña: extranjeros, principalmente estadounidenses y canadienses, mexicanos no sudcalifornianos y todosanteños.

  15. BCS-BEC crossover at finite temperature for superfluid trapped Fermi atoms

    International Nuclear Information System (INIS)

    Perali, A.; Pieri, P.; Pisani, L.; Strinati, G.C.

    2004-01-01

    We consider the BCS-BEC (Bose-Einstein-condensate) crossover for a system of trapped Fermi atoms at finite temperature, both below and above the superfluid critical temperature, by including fluctuations beyond mean field. We determine the superfluid critical temperature and the pair-breaking temperature as functions of the attractive interaction between Fermi atoms, from the weak- to the strong-coupling limit (where bosonic molecules form as bound-fermion pairs). Density profiles in the trap are also obtained for all temperatures and couplings

  16. Optimizing solubility and permeability of a biopharmaceutics classification system (BCS) class 4 antibiotic drug using lipophilic fragments disturbing the crystal lattice.

    Science.gov (United States)

    Tehler, Ulrika; Fagerberg, Jonas H; Svensson, Richard; Larhed, Mats; Artursson, Per; Bergström, Christel A S

    2013-03-28

    Esterification was used to simultaneously increase solubility and permeability of ciprofloxacin, a biopharmaceutics classification system (BCS) class 4 drug (low solubility/low permeability) with solid-state limited solubility. Molecular flexibility was increased to disturb the crystal lattice, lower the melting point, and thereby improve the solubility, whereas lipophilicity was increased to enhance the intestinal permeability. These structural changes resulted in BCS class 1 analogues (high solubility/high permeability) emphasizing that simple medicinal chemistry may improve both these properties.

  17. Turismo y Sustentabilidad en Pequeñas Localidades Localidades Costeras de Baja California Sur (BCS

    Directory of Open Access Journals (Sweden)

    Reyna Ibañez Pérez

    2014-01-01

    Full Text Available El fomento del turismo se realiza en sitios que, aunque pequeños, cuentan con atractivos naturales y culturales, tal es el caso de las zonas costeras. Tan solo en México, se estima que existen más de 1,100 comunidades que dependen directamente de dicha actividad, esta te ndencia se refleja, de igual manera, en pequeñas localidades costeras de Baja California Sur (BCS. En este sentido, el objetivo de este trabajo fue realizar un an álisis exploratorio que permitió detectar a las comunidades costeras de BCS, donde el turismo genera un aporte importante a su economía local, además , se buscó identificar la problemática general que éstas enfrentan. Para realizar dicho estudio se revisó literatura, se organizó información estadística y se elaboró un análisis Fortalezas, Oportunidades, Debilidades y Amenazas (FODA. Los resultad os apuntan a que, en BCS, existen más de 35 localidades ru rales vinculadas con dicha actividad que comparten como problemática la escasa in fraestructura y la carencia de medidas de control de la afluencia turística. La principal recomendación es desarrollar líneas de investigación que permitan aportar elementos para medir la sustentabilidad turística a nivel local y, co n base en ello, diseñar medidas para la adecuada conducción de tan importante actividad.

  18. BEC-BCS-laser crossover in Coulomb-correlated electron-hole-photon systems

    International Nuclear Information System (INIS)

    Yamaguchi, M; Kamide, K; Ogawa, T; Yamamoto, Y

    2012-01-01

    Many-body features caused by Coulomb correlations are of great importance for understanding phenomena pertaining to polariton systems in semiconductor microcavities, i.e. electron-hole-photon systems. Remarkable many-body effects are shown to exist in both thermal-equilibrium phases and non-equilibrium lasing states. We then show a unified framework for connecting the thermal-equilibrium and the non-equilibrium steady states based on a non-equilibrium Green's function approach. Bose-Einstein condensate (BEC)-Bardeen-Cooper-Schrieffer (BCS)-laser crossovers are investigated by using this approach. (paper)

  19. Proposed experimental test of the theory of hole superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, J.E., E-mail: jhirsch@ucsd.edu

    2016-06-15

    Highlights: • The conventional theory of superconductivity predicts no charge flow when the normal-superconductor phase boundary moves. • The theory of hole superconductivity predicts flow and counterflow of charge. • An experiment to measure a voltage is proposed. • No voltage will be measured if the conventional theory is correct. • A voltage will be measured if the theory of hole superconductivity is correct. - Abstract: The theory of hole superconductivity predicts that in the reversible transition between normal and superconducting phases in the presence of a magnetic field there is charge flow in direction perpendicular to the normal-superconductor phase boundary. In contrast, the conventional BCS-London theory of superconductivity predicts no such charge flow. Here we discuss an experiment to test these predictions.

  20. pH-Dependent solubility and permeability criteria for provisional biopharmaceutics classification (BCS and BDDCS) in early drug discovery.

    Science.gov (United States)

    Varma, Manthena V; Gardner, Iain; Steyn, Stefanus J; Nkansah, Paul; Rotter, Charles J; Whitney-Pickett, Carrie; Zhang, Hui; Di, Li; Cram, Michael; Fenner, Katherine S; El-Kattan, Ayman F

    2012-05-07

    The Biopharmaceutics Classification System (BCS) is a scientific framework that provides a basis for predicting the oral absorption of drugs. These concepts have been extended in the Biopharmaceutics Drug Disposition Classification System (BDDCS) to explain the potential mechanism of drug clearance and understand the effects of uptake and efflux transporters on absorption, distribution, metabolism, and elimination. The objective of present work is to establish criteria for provisional biopharmaceutics classification using pH-dependent passive permeability and aqueous solubility data generated from high throughput screening methodologies in drug discovery settings. The apparent permeability across monolayers of clonal cell line of Madin-Darby canine kidney cells, selected for low endogenous efflux transporter expression, was measured for a set of 105 drugs, with known BCS and BDDCS class. The permeability at apical pH 6.5 for acidic drugs and at pH 7.4 for nonacidic drugs showed a good correlation with the fraction absorbed in human (Fa). Receiver operating characteristic (ROC) curve analysis was utilized to define the permeability class boundary. At permeability ≥ 5 × 10(-6) cm/s, the accuracy of predicting Fa of ≥ 0.90 was 87%. Also, this cutoff showed more than 80% sensitivity and specificity in predicting the literature permeability classes (BCS), and the metabolism classes (BDDCS). The equilibrium solubility of a subset of 49 drugs was measured in pH 1.2 medium, pH 6.5 phosphate buffer, and in FaSSIF medium (pH 6.5). Although dose was not considered, good concordance of the measured solubility with BCS and BDDCS solubility class was achieved, when solubility at pH 1.2 was used for acidic compounds and FaSSIF solubility was used for basic, neutral, and zwitterionic compounds. Using a cutoff of 200 μg/mL, the data set suggested a 93% sensitivity and 86% specificity in predicting both the BCS and BDDCS solubility classes. In conclusion, this study identified

  1. Derivation of Ginzburg-Landau theory for a one-dimensional system with contact interaction

    DEFF Research Database (Denmark)

    Frank, Rupert; Hanizl, Christian; Seiringer, Robert

    2013-01-01

    In a recent paper we give the first rigorous derivation of the celebrated Ginzburg-Landau (GL) theory, starting from the microscopic Bardeen-Cooper-Schrieffer (BCS) model. Here we present our results in the simplified case of a one-dimensional system of particles interacting via a delta-potential....

  2. The pairing theory of polarons in real- and impulse spaces

    International Nuclear Information System (INIS)

    Dzhumanov, S.; Abboudy, S.; Baratov, A.A.

    1995-07-01

    A consistent pairing theory of carriers in real- and impulse spaces is developed. The pairing of different free (F), delocalized (D) and self-trapped (S) carriers in real-space, leading to the formation of various bipolaronic states are considered within the continuum model and adiabatic approximation taking into account the combined effect of the short- and long-range components of electron-lattice interaction with and without electron correlation. The formation possibility of D- and S-bipolarons as a function of ε ∞ /ε 0 are shown. The pairing scenarios of carriers in k-space leading to the formation of different bipolarons (including also Cooper pairs dynamic bipolarons) are considered within the generalized BCS-like model taking into account the combined phonon and polaron-bag mediated processes. It is shown that the pure BCS pairing picture is the particular case of the general BCS-like one. The possible relevance of the obtained results to high-T c superconductors is discussed in details in the framework of a novel two-stage Fermi-Bose-liquid scenarios of superconductivity which is caused by single particle and pair condensation of an attracting bipolarons. (author). 51 refs, 6 figs

  3. Some advances in pairing theory

    International Nuclear Information System (INIS)

    Rowe, D.J.

    2001-01-01

    Two advances are reviewed in the application of pairing-force theory in the nuclear shell model. The first exploits a discovery that a wide range of two-nucleon interactions conserve seniority as a good quantum number. As a consequence, the eigenstates of a Hamiltonian with such an interaction belong to irreducible representations of a compact unitary-symplectic group. This makes it possible to extend the simply-solvable models with J=0 pairing forces to a much richer set of models and still obtain states uniquely classified by their seniority and angular momentum quantum numbers. Moreover, many of the low-lying energy levels of such models can be obtained algebraically; in technical terms, the models are in some cases completely solvable and in other cases partially solvable by algebraic methods. The second advance exploits the discovery that, in a coherent state representation, states of good nucleon number can be projected analytically from BCS vacuum and excited quasiparticle states. This makes it possible to perform calculations in a number-projected BCS basis without losing much of the advantage of working of the quasiparticle scheme. (Author)

  4. Approximate energy correction for particle number summetry breaking in constrained Hartree-Fock plus BCS calculations

    International Nuclear Information System (INIS)

    Redon, N.; Meyer, J.; Meyer, M.

    1989-01-01

    An approximate restoration of the particle number symmetry, a la Lipkin-Nogami, is numerically investigated in the context of Constrained Hartree-Fock plus BCS calculations. Its effect is assessed in a variety of physical situations like potential energy landscapes in transitional nuclei, shape isomerism at low spin and fission barriers of actinide nuclei

  5. Study of two-proton radioactivity within the relativistic mean-field plus BCS approach

    International Nuclear Information System (INIS)

    Singh, D.; Saxena, G.

    2012-01-01

    Inspired by recent experimental studies of two-proton radioactivity in the light-medium mass region, we have employed relativistic mean-field plus state-dependent BCS approach (RMF+BCS) to study the ground state properties of selected even-Z nuclei in the region 20 ≤ Z ≤ 40. It is found that the effective potential barrier provided by the Coulomb interaction and that due to centrifugal force may cause a long delay in the decay of some of the nuclei even with small negative proton separation energy. This may cause the existence of proton-rich nuclei beyond the proton drip-line. Nuclei 38 Ti, 42 Cr, 45 Fe, 48 Ni, 55 Zn, 60 Ge, 63, 64 Se, 68 Kr, 72 Sr and 76 Zr are found to be the potential candidates for exhibiting two-proton radioactivity in the region 20 ≤ Z ≤ 40. The reliability of these predictions is further strengthened by the agreement of the calculated results for the ground state properties such as binding energy, one- and two-proton separation energy, proton and neutron radii, and deformation with the available experimental data for the entire chain of the isotopes of the nuclei in the region 20 ≤ Z ≤ 40. (author)

  6. Dipole modes of a superfluid Bose–Fermi mixture in the BCS-BEC crossover

    International Nuclear Information System (INIS)

    Wen, Wen; Chen, Bingyan; Zhang, Xuewu

    2017-01-01

    Motivated by the first experimental realization by the Ecole Normale Supérieure (ENS) group of a mixture of a Bose–Einstein condensate with a Fermi superfluid continuously changing from a Bardeen–Cooper–Schrieffer (BCS) superfluid to a Bose–Einstein condensate (BEC) (Ferrier-Barbut et al 2014 Science 345 1035), we analytically study the dipole modes of the superfluid Bose–Fermi mixture in the BCS-BEC crossover. The analytical approach can explicitly reveal relationships between the frequencies of the dipole modes and the microscopic properties of the novel system. We start from coupled hydrodynamic equations, where the equation of state for the Fermi superfluid in the crossover is an analytical fitting formula based on experimental data, and by using a scaling approach we analytically study eigenfrequencies of the dipole modes for the coupled system in the ENS experimental parameters. Without the boson–fermion interaction in the equilibrium density profiles, our theoretical results can be reduced to the mean-field model and is consistent with the experimental data. However, by further taking into account the boson–fermion interaction numerically and analytically, we find that the results disagree with the experiment, especially in the parameter regime where the boson interaction is smaller than the boson–fermion interaction. (paper)

  7. Structure of even-odd spherical nuclei using the BCS approximations and the ACQPV model: application to isotones with N=82 and Ni, Zn and Cs'' isotopes

    International Nuclear Information System (INIS)

    Losano, L.

    1986-01-01

    Calculations of the (E,J Π ) spectra and the electromagnetic properties (fe,Q,BEZ,BM1) are made for Ni odd isotopes, and odd isotones with N=82, using the Shell Model (SM), the usual BCS approximation (one and three quasiparticles), blocking BCS (BBCS) and projected BCS (PBCS). The importance of the five quasiparticle correlations and of the correlation introduced in BCS are examined in detail. The collective degrees of freedom of the core are introduced through the quasiparticle-cluster-vibrator coupling (QPCVC), so that this formalism permits as well the inclusion of blocking as the projection in number of particles in the cluster of one and three quasiparticles. Comparative calculations are made between the version with blocking (BQPCV) and with projection (PQPCV) for spectra and electromagnetic properties of Zn old isotopes. The projected version is applied to the cesium isotopes in the description of the 5/2 + states generated by the anomalous coupling. In all examined cases, the comparison with the available experimental data is also shown. (L.C.) [pt

  8. Mechanistic investigation of food effect on disintegration and dissolution of BCS class III compound solid formulations: the importance of viscosity.

    Science.gov (United States)

    Radwan, Asma; Amidon, Gordon L; Langguth, Peter

    2012-10-01

    A negative food effect, i.e. a decrease in bioavailability upon the co-administration of compounds together with food, has been attributed particularly with high solubility/low permeability compounds (BCS class III). Different mechanisms have been proposed including intestinal dilution leading to a lower concentration gradient across the intestinal wall as well as binding of the active pharmaceutical ingredient to food components in the intestine and thereby decreasing the fraction of the dose available for absorption. These mechanisms refer primarily to the compound and not to the dosage form. An increase in viscosity of the dissolution fluid will in particular affect the absorption of BCS type III compounds with preferential absorption in the upper small intestine if the API release is delayed from the dosage form. The present study demonstrated that the increase in viscosity of the dissolution medium, following ingestion of a solid meal, may drastically reduce disintegration and dissolution. For that purpose the viscosity of the standard FDA meal was determined and simulated by solutions of HPMC in buffer. As model formulations, three commercially available tablets containing trospium chloride, a BCS class III m-cholinoreceptor antagonist was used. Trospium chloride drug products have been described to undergo a negative food effect of more than 80% following ingestion with food. The tablets showed prolonged disintegration times and reduced dissolution rates in viscous media, which could be attributed to changes in the liquid penetration rates. The effect was particularly significant for film-coated tablets relative to uncoated dosage forms. The results show the necessity of considering media viscosity when designing in vitro models of drug release for BCS type III drug formulations. Copyright © 2012 John Wiley & Sons, Ltd.

  9. Solar flare hard and soft x ray relationship determined from SMM HXRBS and BCS data

    Science.gov (United States)

    Toot, G. David

    1989-01-01

    The exact nature of the solar flare process is still somewhat a mystery. A key element to understanding flares if the relationship between the hard x rays emitted by the most energetic portions of the flare and the soft x rays from other areas and times. This relationship was studied by comparing hard x ray light curved from the Hard X-Ray Burst Spectrometer (HXRBS) with the soft x ray light curve and its derivation from the Bent Crystal Spectrometer (BCS) which is part of the X-Ray Polychrometer (XRP), these instruments being on the Solar Maximum Mission spacecraft (SMM). Data sample was taken from flares observed with the above instruments during 1980, the peak of the previous maximum of solar activity. Flares were chosen based on complete coverage of the event by several instruments. The HXRBS data covers the x ray spectrum from about 25 keV to about 440 keV in 15 spectral channels, while the BCS data used covers a region of the Spectrum around 3 angstroms including emission from the Ca XIX ion. Both sets of data were summed over their spectral ranges and plotted against time at a maximum time resolution of around 3 seconds. The most popular theory of flares holds that a beam of electrons produces the hard x rays by bremsstrahlung while the soft x rays are the thermal response to this energy deposition. The question is whether the rate of change of soft x ray emission might reflect the variability of the electron beam and hence the variability of the hard x rays. To address this, we took the time derivative of the soft x ray light curve and compared it to the hard flares, 12 of them showed very closed agreement between the soft x ray derivative and the hard x ray light curve. The other five did not show this behavior but were similar to each other in general soft x ray behavior. Efforts to determine basic differences between the two kinds of flares continue. In addition the behavior of soft x ray temperature of flares was examined.

  10. Crossover from BCS to composite boson (local pair) superconductivity in quasi-2D systems

    International Nuclear Information System (INIS)

    Gorbar, E.V.; Loktev, V.M.; Sharapov, S.G.

    1995-01-01

    The crossover from cooperative Cooper pairing to independent bound state (composite bosons) formation and condensation in quasi-2 D systems is studied. It is shown that at low carrier density the critical superconducting temperature is equal to the temperature of Bose-condensation of ideal quasi-2 D Bose-gas with heavy dynamical mass, meanwhile at high densities the BCS result remains valid. 15 refs

  11. The Cauchy problem for the Bogolyubov hierarchy of equations. The BCS model

    International Nuclear Information System (INIS)

    Vidybida, A.K.

    1975-01-01

    A chain of Bogolyubov's kinetic equations for an infinite quantum system of particles distributed in space with the mean density 1/V and interacting with the BCS model operator is considered as a single abstract equation in some countable normalized space bsup(v) of sequences of integral operators. In this case an unique solution of the Cauchy problem has been obtained at arbitrary initial conditions from bsup(v), stationary solutions of the equation have been derived, and the class of the initial conditions which approach to stationary ones is indicated

  12. Breast cancer screening (BCS) chart: a basic and preliminary model for making screening mammography more productive and efficient.

    Science.gov (United States)

    Poorolajal, Jalal; Akbari, Mohammad Esmaeil; Ziaee, Fatane; Karami, Manoochehr; Ghoncheh, Mahshid

    2017-05-15

    The breast cancer screening (BCS) chart is suggested as a basic and preliminary tool to improve efficiency of screening mammography. We conducted this case-control study in 2016 and enrolled 1422 women aged 30-75 years, including 506 women with breast cancer (cases) and 916 women without breast cancer (controls). We developed the BCS chart using a multiple logistic regression analysis. We combined the risks of breast cancer to predict the individual risk of breast cancer. Then, we stratified and colored the predicted risk probabilities as follows: green), 05-09% (yellow), 10-14% (orange), 15-19% (red), 20-24% (brown) and ≥25% (black). The BCS chart provides the risk probability of breast cancer, based on age, body mass index, late menopause, having a benign breast disease and a positive family history of breast cancer among the first-degree or the second/third-degree relatives. According to this chart, an individual can be classified in a category of low risk (green), medium risk (yellow and orange), high risk (red and brown) and very high risk (black) for breast cancer. This chart is a flexible and easy to use tool that can detect high-risk subjects and make the screening program more efficient and productive. © The Author 2017. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  13. Superconductivity theory applied to the periodic table of the elements

    Energy Technology Data Exchange (ETDEWEB)

    Elifritz, T.L. [Information Corporation, Madison, WI (United States)

    1994-12-31

    The modern theory of superconductivity, based upon the BCS to Bose-Einstein transition, is applied to the periodic table of the elements, in order to isolate the essential features of high temperature superconductivity and to predict its occurrence within the periodic table. It is predicted that Sodium-Ammonia, Sodium Zinc Phosphide and Bismuth (I) Iodide are promising materials for experimental explorations of high temperature superconductivity.

  14. Superconductivity theory applied to the periodic table of the elements

    International Nuclear Information System (INIS)

    Elifritz, T.L.

    1994-01-01

    The modern theory of superconductivity, based upon the BCS to Bose-Einstein transition, is applied to the periodic table of the elements, in order to isolate the essential features of high temperature superconductivity and to predict its occurrence within the periodic table. It is predicted that Sodium-Ammonia, Sodium Zinc Phosphide and Bismuth (I) Iodide are promising materials for experimental explorations of high temperature superconductivity

  15. Superconductivity theory applied to the periodic table of the elements

    Science.gov (United States)

    Elifritz, Thomas Lee

    1995-01-01

    The modern theory of superconductivity, based upon the BCS to Bose-Einstein transition is applied to the periodic table of the elements, in order to isolate the essential features of of high temperature superconductivity and to predict its occurrence with the periodic table. It is predicted that Sodium-Ammonia, Sodium Zinc Phosphide and Bismuth (I) Iodide are promising materials for experimental explorations of high temperature superconductivity.

  16. Simultaneous projection of particle-number and angular momentum BCS wave-functions in the rare-earth nuclei

    International Nuclear Information System (INIS)

    Oudih, M.R.; Benhamouda, N.; Fellah, M.; Allal, N.H.

    2000-01-01

    A method of simultaneous particle-number and angular-momentum projection of the BCS wave-function is presented. The particle number projection method is of FBCS type. In the frame work of the adiabatic approximation, the rotational energies of the axially symmetric even-even nuclei are established and numerically calculated for the rare-earth region. (author)

  17. Theory of Kondo effect in superconductors, 2

    International Nuclear Information System (INIS)

    Ichinose, Shin-ichi

    1977-01-01

    Thermodynamic properties of superconducting alloys near the transition temperature are studied within the interpolation approximation which is constructed so as to coincide with theories in limiting cases. By the use of this approximation, the specific heat jump at the transition temperature is calculated in the case of the magnitude of the impurity spin being 1/2. The result shows a continuous change of the specific heat jump with T sub(K)/T sub(c0) from the Abrikosov-Gorkov value to essentially BCS-like behavior in contrast to the Mueller-Hartmann-Zittartz theory. One has an example of a cross over between a weak coupling situation at T sub(K)/T sub(c0) > 1. The Hartree-Fock theory is also discussed in connection with the present calculation. (auth.)

  18. Renormalization group theory impact on experimental magnetism

    CERN Document Server

    Köbler, Ulrich

    2010-01-01

    Spin wave theory of magnetism and BCS theory of superconductivity are typical theories of the time before renormalization group (RG) theory. The two theories consider atomistic interactions only and ignore the energy degrees of freedom of the continuous (infinite) solid. Since the pioneering work of Kenneth G. Wilson (Nobel Prize of physics in 1982) we know that the continuous solid is characterized by a particular symmetry: invariance with respect to transformations of the length scale. Associated with this symmetry are particular field particles with characteristic excitation spectra. In diamagnetic solids these are the well known Debye bosons. This book reviews experimental work on solid state physics of the last five decades and shows in a phenomenological way that the dynamics of ordered magnets and conventional superconductors is controlled by the field particles of the infinite solid and not by magnons and Cooper pairs, respectively. In the case of ordered magnets the relevant field particles are calle...

  19. Investigating the Discriminatory Power of BCS-Biowaiver in Vitro Methodology to Detect Bioavailability Differences between Immediate Release Products Containing a Class I Drug.

    Science.gov (United States)

    Colón-Useche, Sarin; González-Álvarez, Isabel; Mangas-Sanjuan, Victor; González-Álvarez, Marta; Pastoriza, Pilar; Molina-Martínez, Irene; Bermejo, Marival; García-Arieta, Alfredo

    2015-09-08

    The purpose of this work is to investigate the discriminatory power of the Biopharmaceutics Classification System (BCS)-biowaiver in vitro methodology, i.e., to investigate if a BCS-biowaiver approach would have detected the Cmax differences observed between two zolpidem tablets and to identify the cause of the in vivo difference. Several dissolution conditions were tested with three zolpidem formulations: the reference (Stilnox), a bioequivalent formulation (BE), and a nonbioequivalent formulation (N-BE). Zolpidem is highly soluble at pH 1.2, 4.5, and 6.8. Its permeability in Caco-2 cells is higher than that of metoprolol and its transport mechanism is passive diffusion. None of the excipients (alone or in combination) showed any effect on permeability. All formulations dissolved more than 85% in 15 min in the paddle apparatus at 50 rpm in all dissolution media. However, at 30 rpm the nonbioequivalent formulation exhibited a slower dissolution rate. A slower gastric emptying rate was also observed in rats for the nonbioequivalent formulation. A slower disintegration and dissolution or a delay in gastric emptying might explain the Cmax infra-bioavailability for a highly permeable drug with short half-life. The BCS-biowaiver approach would have declared bioequivalence, although the in vivo study was not conclusive but detected a 14% mean difference in Cmax that precluded the bioequivalence demonstration. Nonetheless, these findings suggest that a slower dissolution rate is more discriminatory and that rotation speeds higher than 50 rpm should not be used in BCS-biowaivers, even if a coning effect occurs.

  20. Hartree-Fock+BCS approach to unstable nuclei with the Skyrme force

    International Nuclear Information System (INIS)

    Tajima, Naoki

    2001-01-01

    We reanalyze the results of our extensive Hartree-Fock+BCS calculation from new points of view paying attention to the properties of unstable nuclei. The calculation has been done with the Skyrme SIII force for the ground and shape isomeric states of 1029 even-even nuclei ranging 2≤Z≤114. We also discuss the advantages of the employed three-dimensional Cartesian-mesh representation, especially on its remarkably high precision with apparently coarse meshes when applied to atomic nuclei. In Appendices we give the coefficients of finite-point numerical differentiation and integration formulae suitable for Cartesian mesh representation and elucidate the features of each formula and the differences from a method based on the Fourier transformation. (author)

  1. Importance of the single-particle continuum in BCS pairing with a pseudostate basis

    Directory of Open Access Journals (Sweden)

    Lay J. A.

    2016-01-01

    Full Text Available In a recent work [arXiv:1510.03185] the use of the Transformed Harmonic Oscillator (THO basis for the discretization of the singleparticle continuum into a Generalized Bardeen-Cooper-Schrieffer (BCS formalism was proposed for the description of weakly bound nuclei. We make use of the flexibility of this formalism to study the evolution of the pairing when the nucleus becomes more and more weakly bound. Specifically we focus on the evolution of the occupation of the different partial waves in 22O when the Fermi level approaches zero.

  2. Purely in silico BCS classification: science based quality standards for the world's drugs.

    Science.gov (United States)

    Dahan, Arik; Wolk, Omri; Kim, Young Hoon; Ramachandran, Chandrasekharan; Crippen, Gordon M; Takagi, Toshihide; Bermejo, Marival; Amidon, Gordon L

    2013-11-04

    BCS classification is a vital tool in the development of both generic and innovative drug products. The purpose of this work was to provisionally classify the world's top selling oral drugs according to the BCS, using in silico methods. Three different in silico methods were examined: the well-established group contribution (CLogP) and atom contribution (ALogP) methods, and a new method based solely on the molecular formula and element contribution (KLogP). Metoprolol was used as the benchmark for the low/high permeability class boundary. Solubility was estimated in silico using a thermodynamic equation that relies on the partition coefficient and melting point. The validity of each method was affirmed by comparison to reference data and literature. We then used each method to provisionally classify the orally administered, IR drug products found in the WHO Model list of Essential Medicines, and the top-selling oral drug products in the United States (US), Great Britain (GB), Spain (ES), Israel (IL), Japan (JP), and South Korea (KR). A combined list of 363 drugs was compiled from the various lists, and 257 drugs were classified using the different in silico permeability methods and literature solubility data, as well as BDDCS classification. Lastly, we calculated the solubility values for 185 drugs from the combined set using in silico approach. Permeability classification with the different in silico methods was correct for 69-72.4% of the 29 reference drugs with known human jejunal permeability, and for 84.6-92.9% of the 14 FDA reference drugs in the set. The correlations (r(2)) between experimental log P values of 154 drugs and their CLogP, ALogP and KLogP were 0.97, 0.82 and 0.71, respectively. The different in silico permeability methods produced comparable results: 30-34% of the US, GB, ES and IL top selling drugs were class 1, 27-36.4% were class 2, 22-25.5% were class 3, and 5.46-14% were class 4 drugs, while ∼8% could not be classified. The WHO list

  3. Systematic study of even-even nuclei with Hartree-Fock+BCS method using Skyrme SIII force

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, Naoki; Takahara, Satoshi; Onishi, Naoki [Tokyo Univ. (Japan). Coll. of Arts and Sciences

    1997-03-01

    We have applied the Hartree-Fock+BCS method with Skyrme SIII force formulated in a three-dimensional Cartesian-mesh representation to even-even nuclei with 2 {<=} Z {<=} 114. We discuss the results concerning the atomic masses, the quadrupole (m=0, 2) and hexadecapole (m=0, 2, 4) deformations, the skin thicknesses, and the halo radii. We also discuss the energy difference between oblate and prolate solutions and the shape difference between protons and neutrons. (author)

  4. Exotic open-flavor bcq¯q¯, bcs¯s¯ and qcq¯b¯, scs¯b¯ tetraquark states

    Science.gov (United States)

    Chen, Wei; Steele, T. G.; Zhu, Shi-Lin

    2014-03-01

    We study the exotic bcq¯q¯, bcs¯s¯ and qcq¯b¯, scs¯b¯ systems by constructing the corresponding tetraquark currents with JP=0+ and 1+. After investigating the two-point correlation functions and the spectral densities, we perform QCD sum rule analysis and extract the masses of these open-flavor tetraquark states. Our results indicate that the masses of both the scalar and axial vector tetraquark states are about 7.1-7.2 GeV for the bcq¯q¯ system and 7.2-7.3 GeV for the bcs¯s¯ system. For the qcq¯b¯ tetraquark states with JP=0+ and 1+, their masses are extracted to be around 7.1 GeV. The masses for the scalar and axial vector scs¯b¯ states are 7.1 and 6.9-7.1 GeV, respectively. The tetraquark states qcq¯b¯ and scs¯b¯ lie below the thresholds of D(*)B(*) and Ds(*)Bs(*) respectively, but they can decay into Bc plus a light meson. However, the tetraquark states bcq¯q¯ and bcs¯s¯ lie below the D(*)B¯(*) and Ds(*)B¯s(*) thresholds, suggesting dominantly weak decay mechanisms.

  5. BCS superconductors: The out-of-equilibrium response to a laser pulse

    Science.gov (United States)

    Avella, Adolfo

    2018-05-01

    The dynamics of a 2D d-wave BCS superconductor driven out-of-equilibrium by a perpendicularly-impinging polarized laser pulse is analyzed on varying the laser pulse characteristics. The observed effects include: oscillations both in the amplitude and in the phase of the superconducting order parameter, suppression of the superconductivity, but also its enhancement with a strong dependence on all varying parameters and, in particular, on the polarization in plane of the applied vector potential and on the value of its frequency. This study opens up the possibility to distinguish very clearly the behavior of the nodal and anti-nodal non-thermal excitations and to tackle some of the puzzling results of the current experimental scenario in the field.

  6. The boson expansion theory as the nuclear structure theory for the heavy nuclei

    International Nuclear Information System (INIS)

    Kim, H.B.

    1987-01-01

    Sometime sago, Kishimoto and Tamura developed a formalism of boson expansion theory (BET), and then Weeks and Tamura showed that it fitted many experimental data of collective nuclei. This formalism has recently been simplified significantly be Pedrocchi, Jamaluddin and Tamura. The new and old theories are very closely related but are not exactly the same. It has thus been desired to see whether the new theory can also fit data, and to show that it indeed works well constitutes a major part of this thesis. It is in fact seen that a number of data of Sm, Os and Pt isotopes are explained nicely. Since the new form of the theory is rather simple, it permits us to take into account easily the effects of noncollective states to the behavior of collective states. This thesis shows that are remarkably improved fit to data of magnetic moments of SM isotopes is achieved in this way. The thesis discusses one additional subject. It is a result of an effort made to improve the BET by removing as much as possible the error due to the use of the BCS theory. This was done by applying a method developed by Li to the Dyson form of BET. A way to develop this work further is suggested

  7. Provisional in-silico biopharmaceutics classification (BCS) to guide oral drug product development.

    Science.gov (United States)

    Wolk, Omri; Agbaria, Riad; Dahan, Arik

    2014-01-01

    The main objective of this work was to investigate in-silico predictions of physicochemical properties, in order to guide oral drug development by provisional biopharmaceutics classification system (BCS). Four in-silico methods were used to estimate LogP: group contribution (CLogP) using two different software programs, atom contribution (ALogP), and element contribution (KLogP). The correlations (r(2)) of CLogP, ALogP and KLogP versus measured LogP data were 0.97, 0.82, and 0.71, respectively. The classification of drugs with reported intestinal permeability in humans was correct for 64.3%-72.4% of the 29 drugs on the dataset, and for 81.82%-90.91% of the 22 drugs that are passively absorbed using the different in-silico algorithms. Similar permeability classification was obtained with the various in-silico methods. The in-silico calculations, along with experimental melting points, were then incorporated into a thermodynamic equation for solubility estimations that largely matched the reference solubility values. It was revealed that the effect of melting point on the solubility is minor compared to the partition coefficient, and an average melting point (162.7 °C) could replace the experimental values, with similar results. The in-silico methods classified 20.76% (± 3.07%) as Class 1, 41.51% (± 3.32%) as Class 2, 30.49% (± 4.47%) as Class 3, and 6.27% (± 4.39%) as Class 4. In conclusion, in-silico methods can be used for BCS classification of drugs in early development, from merely their molecular formula and without foreknowledge of their chemical structure, which will allow for the improved selection, engineering, and developability of candidates. These in-silico methods could enhance success rates, reduce costs, and accelerate oral drug products development.

  8. Theory of fractional quantum hall effect

    International Nuclear Information System (INIS)

    Kostadinov, I.Z.

    1985-08-01

    A theory of the Fractional Quantum Hall Effect is constructed based on magnetic flux fractionization, which lead to instability of the system against selfcompression. A theorem is proved stating that arbitrary potentials fail to lift a specific degeneracy of the Landau level. For the case of 1/3 fractional filling a model 3-particles interaction is constructed breaking the symmetry. The rigid 3-particles wave function plays the role of order parameter. In a BCS type of theory the gap in the single particles spectrum is produced by the 3-particles interaction. The mean field critical behaviour and critical parameters are determined as well as the Ginsburg-Landau equation coefficients. The Hall conductivity is calculated from the first principles and its temperature dependence is found. The simultaneous tunnelling of 3,5,7 etc. electrons and quantum interference effects are predicted. (author)

  9. The (φ4)3+1 theory with infinitesimal bare coupling constants

    International Nuclear Information System (INIS)

    Yotsuyanagi, I.

    1987-01-01

    We study the (φ 4 ) 3+1 theory by means of a variational method improved with a BCS-type vacuum state. We examine the theory with both negative and positive infinitesimal bare coupling constants, where the theory has been suggested to exist nontrivially and stably in the infinite ultraviolet cutoff limit. When the cutoff is sent to infinity, we find the instability of the vacuum energy at the end point value of the variational parameter in the case of the negative bare coupling constant. For the positive bare coupling constant, we can renormalize the vacuum energy without using the extremal condition with respect to the variational mass parameter. We do not find an instability for the whole range of parameters including the end point. We still have a possibility that the theory with this bare coupling constant is nontrivial and stable. (orig.)

  10. Relativistic corrections to the Cooperon mass: BCS versus BEC picture

    Energy Technology Data Exchange (ETDEWEB)

    Lipavský, P., E-mail: lipavsky@karlov.mff.cuni.cz

    2017-02-15

    Highlights: • Tate's measurement of relativistic effects on the Cooper pair mass show the increase while a decrease was expected. • This disagreement raised a question whether it has fundamental significance or is due to the details of the particular physical system being studied. • The most fundamental were speculations about gravitomagnetic forces enhanced by the Higgs mechanism. • These were recently disproved experimentally. • This paper shows that the relativistic mass corrections might be sensitive to the pairing scenario: the predicted mass decrease corresponds to the Bose–Einstein condensation of preformed Cooper pairs, while the pairing in the Bardeen–Cooper–Schrieffer condensate leads to an increase of experimentally observed magnitude. - Abstract: Relativistic corrections to the Cooperon mass are discussed for preformed Cooper pairs that become superconductive via the Bose–Einstein condensation (BEC) and for Cooperons in the Bardeen–Copper–Schrieffer (BCS) condensate. The distinction explains experimental results of Tate et al. (1989).

  11. Proposed experimental test of an alternative electrodynamic theory of superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, J.E., E-mail: jhirsch@ucsd.edu

    2015-01-15

    Highlights: • A new experimental test of electric screening in superconductors is proposed. • The electric screening length is predicted to be much larger than in normal metals. • The reason this was not seen in earlier experiments is explained. • This is not predicted by the conventional BCS theory of superconductivity. - Abstract: An alternative form of London’s electrodynamic theory of superconductors predicts that the electrostatic screening length is the same as the magnetic penetration depth. We argue that experiments performed to date do not rule out this alternative formulation and propose an experiment to test it. Experimental evidence in its favor would have fundamental implications for the understanding of superconductivity.

  12. Regional-Dependent Intestinal Permeability and BCS Classification: Elucidation of pH-Related Complexity in Rats Using Pseudoephedrine

    OpenAIRE

    Fairstein, Moran; Swissa, Rotem; Dahan, Arik

    2013-01-01

    Based on its lower Log P value relative to metoprolol, a marker for the low/high-permeability (Peff) class boundary, pseudoephedrine was provisionally classified as BCS low-permeability compound. On the other hand, following oral administration, pseudoephedrine fraction dose absorbed (Fabs) and systemic bioavailability approaches 100%. This represents a challenge to the generally recognized Peff–Fabs correlation. The purpose of this study was to elucidate the underlying mechanisms behind the ...

  13. Gastrointestinal Behavior of Weakly Acidic BCS Class II Drugs in Man--Case Study of Diclofenac Potassium.

    Science.gov (United States)

    Van Den Abeele, Jens; Brouwers, Joachim; Mattheus, Ruben; Tack, Jan; Augustijns, Patrick

    2016-02-01

    This study aimed to investigate the gastrointestinal supersaturation and precipitation behavior of a weakly acidic Biopharmaceutics Classification System (BCS) Class II drug in healthy volunteers. For this purpose, a tablet containing 50 mg diclofenac potassium (Cataflam(®)) was predissolved in 240 mL of water and this solution was subsequently orally administered to five healthy volunteers under fasted and fed state conditions with or without concomitant use of a proton-pump inhibitor (PPI) (40 mg esomeprazole, Nexiam(®)). Subsequently, total diclofenac content and dissolved intraluminal drug concentrations as well as drug thermodynamic solubility were determined in gastrointestinal aspirates. In all volunteers, gastric supersaturation resulted in precipitation of diclofenac in the stomach. The extent of precipitation correlated well with gastric pH (r = - 0.78). pH dependency of precipitation was corroborated by the absence of precipitate in the stomach after coadministration of a meal and/or a PPI. Diclofenac was found to be fully dissolved in the duodenum in all test conditions. It can be concluded that substantial pH-dependent gastric precipitation of a weakly acidic BCS Class II drug administered as a solution occurs in humans. With regard to its implications for intestinal absorption, results suggest the instantaneous redissolution of gastric drug precipitate upon transfer to the duodenum. Copyright © 2016. Published by Elsevier Inc.

  14. Crecimiento económico, desarrollo sustentable y turismo: Una aproximación del posicionamiento de Baja California Sur (BCS en el Barómetro de Sustentabilidad

    Directory of Open Access Journals (Sweden)

    Reyna Ibáñez Pérez

    2011-01-01

    Full Text Available Uno de los mayores anhelos de toda sociedad es alcanzar un nivel económico elevado; otro es el de tener la oportunidad de disfrutar eternamente de los servicios proporcionados por la madre naturaleza. Sin embargo, las tendencias indican que se experimenta un deterioro importante en el ambiente, a la par, de una elevada concentración de pobreza. Esto, aunado a la dependencia que algunas entidades y países han desarrollado en relación a actividades -como la turística- se ha convertido en una de las preocupaciones centrales de los gobiernos, el establecer mediciones para determinar si las pautas de crecimiento y desarrollo, van acorde con el cuidado del ambiente y el bienestar de las personas. Por ello, dentro de este artículo se analizan la evolución del crecimiento económico y posicionamiento de Baja California Sur (BCS -un estado con importante actividad turística- en el Barómetro de Sustentabilidad. En la introducción, se aprecia la evolución del concepto de crecimiento y desarrollo, para continuar con la caracterización de la zona de estudio. Posteriormente, se detalla la metodología empleada. Enseguida, se estudia la situación actual del sector turístico en BCS y la evolución del crecimiento y desarrollo económico. En el análisis de resultados, se describen los factores que ubican a BCS en un nivel Medio de sustentabilidad. Finalmente, se presentan algunas reflexiones en relación a los retos que en materia de turismo, crecimiento económico, desarrollo sustentable afronta BCS.

  15. Effects of density imbalance on the BCS-BEC crossover in semiconductor electron-hole bilayers

    International Nuclear Information System (INIS)

    Pieri, P.; Strinati, G. C.; Neilson, D.

    2007-01-01

    We study the occurrence of excitonic superfluidity in electron-hole bilayers at zero temperature. We not only identify the crossover in the phase diagram from the BCS limit of overlapping pairs to the BEC limit of nonoverlapping tightly bound pairs but also, by varying the electron and hole densities independently, we can analyze a number of phases that occur mainly in the crossover region. With different electron and hole effective masses, the phase diagram is asymmetric with respect to excess electron or hole densities. We propose, as the criterion for the onset of superfluidity, the jump of the electron and hole chemical potentials when their densities cross

  16. Calculation of TC in a normal-superconductor bilayer using the microscopic-based Usadel theory

    International Nuclear Information System (INIS)

    Martinis, John M.; Hilton, G.C.; Irwin, K.D.; Wollman, D.A.

    2000-01-01

    The Usadel equations give a theory of superconductivity, valid in the diffusive limit, that is a generalization of the microscopic equations of the BCS theory. Because the theory is expressed in a tractable and physical form, even experimentalists can analytically and numerically calculate detailed properties of superconductors in physically relevant geometries. Here, we describe the Usadel equations and review their solution in the case of predicting the transition temperature T C of a thin normal-superconductor bilayer. We also extend this calculation for thicker bilayers to show the dependence on the resistivity of the films. These results, which show a dependence on both the interface resistance and heat capacity of the films, provide important guidance on fabricating bilayers with reproducible transition temperatures

  17. Comparison between a diagrammatic theory for the BCS-BEC crossover and quantum Monte Carlo results

    International Nuclear Information System (INIS)

    Pieri, P.; Pisani, L.; Strinati, G.C.

    2005-01-01

    Predictions for the chemical potential and the excitation gap recently obtained by our diagrammatic theory for the Bardeen-Cooper-Schreiffer-Bose-Einstein Condensation crossover in the superfluid phase are compared with quantum Monte Carlo results at zero temperature now available in the literature. A remarkable agreement is found between the results obtained by the two approaches

  18. The impact of supersaturation level for oral absorption of BCS class IIb drugs, dipyridamole and ketoconazole, using in vivo predictive dissolution system: Gastrointestinal Simulator (GIS).

    Science.gov (United States)

    Tsume, Yasuhiro; Matsui, Kazuki; Searls, Amanda L; Takeuchi, Susumu; Amidon, Gregory E; Sun, Duxin; Amidon, Gordon L

    2017-05-01

    The development of formulations and the assessment of oral drug absorption for Biopharmaceutical Classification System (BCS) class IIb drugs is often a difficult issue due to the potential for supersaturation and precipitation in the gastrointestinal (GI) tract. The physiological environment in the GI tract largely influences in vivo drug dissolution rates of those drugs. Thus, those physiological factors should be incorporated into the in vitro system to better assess in vivo performance of BCS class IIb drugs. In order to predict oral bioperformance, an in vitro dissolution system with multiple compartments incorporating physiologically relevant factors would be expected to more accurately predict in vivo phenomena than a one-compartment dissolution system like USP Apparatus 2 because, for example, the pH change occurring in the human GI tract can be better replicated in a multi-compartmental platform. The Gastrointestinal Simulator (GIS) consists of three compartments, the gastric, duodenal and jejunal chambers, and is a practical in vitro dissolution apparatus to predict in vivo dissolution for oral dosage forms. This system can demonstrate supersaturation and precipitation and, therefore, has the potential to predict in vivo bioperformance of oral dosage forms where this phenomenon may occur. In this report, in vitro studies were performed with dipyridamole and ketoconazole to evaluate the precipitation rates and the relationship between the supersaturation levels and oral absorption of BCS class II weak base drugs. To evaluate the impact of observed supersaturation levels on oral absorption, a study utilizing the GIS in combination with mouse intestinal infusion was conducted. Supersaturation levels observed in the GIS enhanced dipyridamole and ketoconazole absorption in mouse, and a good correlation between their supersaturation levels and their concentration in plasma was observed. The GIS, therefore, appears to represent in vivo dissolution phenomena and

  19. Experimental constraints on theories of high Tc superconductors

    International Nuclear Information System (INIS)

    Little, W.A.

    1989-01-01

    Recent experiments on the high-T c superconductors have begun to narrow the possible theoretical explanations of the phenomenon. Experimental evidence on the size, structure and symmetry of the charge carriers will be reviewed; evidence for and against strong coupling; and, recent results on a search for direct evidence of magnetic signature in the coupling mechanism will be presented. The authors show how these experiments impose strong constraints on the theories of these superconductors. A new type of experiment is also discussed which appears capable of identifying the true nature of the coupling mechanism if the superconductors prove to be BCS-like in nature

  20. Effect of pairing on nuclear dynamics

    International Nuclear Information System (INIS)

    Scamps, Guillaume

    2014-01-01

    Pairing correlations is an essential component for the description of the atomic nuclei. The effects of pairing on static property of nuclei are now well known. In this thesis, the effect of pairing on nuclear dynamics is investigated. Theories that includes pairing are benchmarked in a model case. The TDHF+BCS theory turns out to be a good compromise between the physics taken into account and the numerical cost. This TDHF+BCS theory was retained for realistic calculations. Nevertheless, the application of pairing in the BCS approximation may induce new problems due to (1) the particle number symmetry breaking, (2) the non-conservation of the continuity equation. These difficulties are analysed in detail and solutions are proposed. In this thesis, a 3 dimensional TDHF+BCS code is developed to simulate the nuclear dynamic. Applications to giant resonances show that pairing modify only the low lying peaks. The high lying collective components are only affected by the initial conditions. An exhaustive study of the giant quadrupole resonances with the TDHF+BCS theory is performed on more than 700 spherical or deformed nuclei. Is is shown that the TDHF+BCS theory reproduces well the collective energy of the resonance. After validation on the small amplitude limit problem, the approach was applied to study nucleon transfer in heavy ion reactions. A new method to extract transfer probabilities is introduced. It is demonstrated that pairing significantly increases the two-nucleon transfer probability. (author) [fr

  1. Theory of novel normal and superconducting states in doped oxide high-Tc superconductors

    International Nuclear Information System (INIS)

    Dzhumanov, S.

    2001-10-01

    A consistent and complete theory of the novel normal and superconducting (SC) states of doped high-T c superconductors (HTSC) is developed by combining the continuum model of carrier self-trapping, the tight-binding model and the novel Fermi-Bose-liquid (FBL) model. The ground-state energy of carriers in lightly doped HTSC is calculated within the continuum model and adiabatic approximation using the variational method. The destruction of the long-range antiferromagnetic (AF) order at low doping x≥ x cl ≅0.015, the formation of the in-gap states or bands and novel (bi)polaronic insulating phases at x c2 ≅0.06-0.08, and the new metal- insulator transition at x≅x c2 in HTSC are studied within the continuum model of impurity (defect) centers and large (bi)polarons by using the appropriate tight-binding approximations. It is found that the three-dimensional (3d) large (bi)polarons are formed at ε ∞ /ε 0 ≤0.1 and become itinerant when the (bi)polaronic insulator-to-(bi)polaronic metal transitions occur at x x c2 . We show that the novel pseudogapped metallic and SC states in HTSC are formed at x c2 ≤x≤x p ≅0.20-0.24. We demonstrate that the large polaronic and small BCS-like pairing pseudogaps opening in the excitation spectrum of underdoped (x c2 BCS =0.125), optimally doped (x BCS o ≅0.20) and overdoped (x>x o ) HTSC above T c are unrelated to superconductivity and they are responsible for the observed anomalous optical, transport, magnetic and other properties of these HTSC. We develop the original two-stage FBL model of novel superconductivity describing the combined novel BCS-like pairing scenario of fermions and true superfluid (SF) condensation scenario of composite bosons (i.e. bipolarons and cooperons) in any Fermi-systems, where the SF condensate gap Δ B and the BCS-like pairing pseudogap Δ F have different origins. The pair and single particle condensations of attracting 3d and two- dimensional (2d) composite bosons are responsible for

  2. Mathematical methods of many-body quantum field theory

    CERN Document Server

    Lehmann, Detlef

    2004-01-01

    Mathematical Methods of Many-Body Quantum Field Theory offers a comprehensive, mathematically rigorous treatment of many-body physics. It develops the mathematical tools for describing quantum many-body systems and applies them to the many-electron system. These tools include the formalism of second quantization, field theoretical perturbation theory, functional integral methods, bosonic and fermionic, and estimation and summation techniques for Feynman diagrams. Among the physical effects discussed in this context are BCS superconductivity, s-wave and higher l-wave, and the fractional quantum Hall effect. While the presentation is mathematically rigorous, the author does not focus solely on precise definitions and proofs, but also shows how to actually perform the computations.Presenting many recent advances and clarifying difficult concepts, this book provides the background, results, and detail needed to further explore the issue of when the standard approximation schemes in this field actually work and wh...

  3. Trends in Energy Management Technology: BCS Integration Technologies - Open Communications Networking

    Energy Technology Data Exchange (ETDEWEB)

    Webster, Tom

    2002-09-18

    Our overall purpose in writing this series of articles is to provide Federal energy managers some basic informational tools to assist their decision making process relative to energy management systems design, specification, procurement, and energy savings potential. Since Federal buildings rely on energy management systems more than their commercial counterparts, it is important for energy practitioners to have a high level of knowledge and understanding of these complex systems. This is the second article in a series and will focus on building control system (BCS) networking fundamentals and an assessment of current approaches to open communications protocols. This is important because networking is a complex subject and the networks form the basic infrastructure for energy management functions and for integrating a wide variety of OEM equipment into a complete EMCIS. The first article [1] covered enabling technologies for emerging energy management systems. Future topics will concentrate on more practical aspects including applications software, product offerings, networking strategies, and case studies of actual installations. Please refer to the first article for a more complete overview of the purpose and background for this series.

  4. G.L. Amidon, H. Lennernas, V.P. Shah, and J.R. Crison. A theoretical basis for a biopharmaceutic drug classification: the correlation of in vitro drug product dissolution and in vivo bioavailability, Pharm Res 12, 413-420, 1995--backstory of BCS.

    Science.gov (United States)

    Shah, Vinod P; Amidon, Gordon L

    2014-09-01

    The Biopharmaceutics Classification System (BCS) has become widely accepted today in the academic, industrial, and regulatory world. While the initial application of the BCS was to regulatory science bioequivalence (BE) issues and related implications, it has come to be utilized widely by the pharmaceutical industry in drug discovery and development as well. This brief manuscript will relate the story of the BCS development. While much of the ground work for the BCS goes back to the pharmacokinetic and drug absorption research by Gordon Amidon (GLA) in the 1970s and 1980s, the realization of the need for a classification or categorization of drug and drug products for setting dissolution standards became apparent to GLA during his 1990-1991 sabbatical year at the FDA. Initiated at the invitation of the then CEDR director, Dr. Carl Peck, to become a visiting scientist at the FDA, the goal was to promote regulatory research at the FDA, in my case, in biopharmaceutics, and to develop a science-based system to simplify regulatory requirements.

  5. Analytic solution of the BCS gap equation with a logarithmic singularity in the density of states

    International Nuclear Information System (INIS)

    Bhardwaj, A.; Muthu, S.K.

    1999-01-01

    The Bardeen-Cooper-Schrieffer (BCS) gap equation is solved analytically for a density of states function with a logarithmic singularity. It is an extension of our earlier work where we had assumed a constant density of states. We continue to work in the weak-coupling limit and consider both phononic and non-phononic pairings. Expressions are obtained for T c , Δ 0 (the gap at T=0), and the jump in the electronic specific heat at T=T c . We also calculate the isotope exponent and show that it is possible to reproduce the broad features of the experimental results in this framework. (orig.)

  6. Structure and functioning of a multidisciplinary 'Heart Team' for patients with coronary artery disease: rationale and recommendations from a joint BCS/BCIS/SCTS working group.

    Science.gov (United States)

    Luckraz, Heyman; Norell, Michael; Buch, Mamta; James, Rachael; Cooper, Graham

    2015-10-01

    The decision-making process in the management of patients with ischaemic heart disease has historically been the responsibility of the cardiologist and encompasses medical management, percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG). Currently, there is significant geographical variability in the PCI:CABG ratio. There are now emerging recommendations that this decision-making process should be carried out through a multidisciplinary approach, namely the Heart Team. This work was carried out on behalf of The British Cardiovascular Society (BCS), Society for Cardiothoracic Surgery in Great Britain and Ireland (SCTS) and British Cardiovascular Intervention Society (BCIS). This manuscript sets out the principles for the functioning of the Heart Team. This work has been approved by the Executive Committees of BCS/BCIS/SCTS. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  7. Splitting and oscillation of Majorana zero modes in the p-wave BCS-BEC evolution with plural vortices

    International Nuclear Information System (INIS)

    Mizushima, T.; Machida, K.

    2010-01-01

    We investigate how the vortex-vortex separation changes Majorana zero modes in the vicinity of the BCS-BEC (Bose-Einstein condensation) topological phase transition of p-wave resonant Fermi gases. By analytically and numerically solving the Bogoliubov-de Gennes equation for spinless p-wave superfluids with plural vortices, it is demonstrated that the quasiparticle tunneling between neighboring vortices gives rise to the quantum oscillation of the low-lying spectra on the scale of the Fermi wavelength in addition to the exponential splitting. This rapid oscillation, which appears in the weak-coupling regime as a consequence of quantum oscillations of quasiparticle wave functions, disappears in the vicinity of the BCS-BEC topological phase transition. This is understandable from that the wave function of the Majorana zero modes is described by the modified Bessel function in the strong-coupling regime, and thus it becomes spread over the vortex core region. Due to the exponential divergence of the modified Bessel function, the concrete realization of the Majorana zero modes near the topological phase transition requires the neighboring vortices to be separated beyond the length scale defined by the coherence length and the dimensionless coupling constant. All these behaviors are also confirmed by carrying out the full numerical diagonalization of the nonlocal Bogoliubov-de Gennes equation in a two-dimensional geometry. Furthermore, this argument is expanded into the case of three-vortex systems, where a pair of core-bound and edge-bound Majorana states survive at zero-energy state regardless of the vortex separation.

  8. Effects of PEGylated lipid nanoparticles on the oral absorption of one BCS II drug: a mechanistic investigation

    Directory of Open Access Journals (Sweden)

    Zhang XW

    2014-11-01

    Full Text Available Xingwang Zhang,* Guijiang Chen,* Tianpeng Zhang, Zhiguo Ma, Baojian WuDivision of Pharmaceutics, College of Pharmacy, Jinan University, Guangzhou, People’s Republic of China*These authors contributed equally to this workAbstract: Lipid nanocarriers are becoming a versatile platform for oral delivery of lipophilic drugs. In this article, we aimed to explore the gastrointestinal behaviors of lipid nanoparticles and the effect of PEGylation on oral absorption of fenofibrate (FN, a Biopharmaceutics Classification System (BCS II model drug. FN-loaded PEGylated lipid nanoparticles (FN-PLNs were prepared by the solvent-diffusion method and characterized by particle size distribution, morphology, Fourier transform infrared spectroscopy, and drug release. Lipolytic experiments were performed to assess the resistance of lipid nanoparticles against pancreatic lipase. Pharmacokinetics was evaluated in rats after oral administration of FN preparations. The obtained FN-PLNs were 186.7 nm in size with an entrapment efficiency of >95%. Compared to conventional lipid nanoparticles, PLNs exhibited slower drug release in the lipase-containing medium, strikingly reduced mucin binding, and suppressed lipolysis in vitro. Further, oral absorption of FN was significantly enhanced using PLNs with relative bioavailability of 123.9% and 157.0% to conventional lipid nanoparticles and a commercial formulation (Lipanthyl®, respectively. It was demonstrated that reduced mucin trapping, suppressed lipolysis, and/or improved mucosal permeability were responsible for increased oral absorption. These results facilitated a better understanding of the in vivo fate of lipid nanoparticles, and suggested the potential of PLNs as oral carriers of BCS II drugs.Keywords: fenofibrate, lipid nanoparticles, PEGylation, oral bioavailability, absorption mechanism

  9. The low/high BCS permeability class boundary: physicochemical comparison of metoprolol and labetalol.

    Science.gov (United States)

    Zur, Moran; Gasparini, Marisa; Wolk, Omri; Amidon, Gordon L; Dahan, Arik

    2014-05-05

    Although recognized as overly conservative, metoprolol is currently the common low/high BCS permeability class boundary reference compound, while labetalol was suggested as a potential alternative. The purpose of this study was to identify the various characteristics that the optimal marker should exhibit, and to investigate the suitability of labetalol as the permeability class reference drug. Labetalol's BCS solubility class was determined, and its physicochemical properties and intestinal permeability were thoroughly investigated, both in vitro and in vivo in rats, considering the complexity of the whole of the small intestine. Labetalol was found to be unequivocally a high-solubility compound. In the pH range throughout the small intestine (6.5-7.5), labetalol exhibited pH-dependent permeability, with higher permeability at higher pH values. While in vitro octanol-buffer partitioning (Log D) values of labetalol were significantly higher than those of metoprolol, the opposite was evident in the in vitro PAMPA permeability assay. The results of the in vivo perfusion studies in rats lay between the two contradictory in vitro studies; metoprolol was shown to have moderately higher rat intestinal permeability than labetalol. Theoretical distribution of the ionic species of the drugs was in corroboration with the experimental in vitro and the in vivo data. We propose three characteristics that the optimal permeability class reference drug should exhibit: (1) fraction dose absorbed in the range of 90%; (2) the optimal marker drug should be absorbed largely via passive transcellular permeability, with no/negligible carrier-mediated active intestinal transport (influx or efflux); and (3) the optimal marker drug should preferably be nonionizable. The data presented in this paper demonstrate that neither metoprolol nor labetalol can be regarded as optimal low/high-permeability class boundary standard. While metoprolol is too conservative due to its complete absorption

  10. Effective field theories for correlated electrons

    International Nuclear Information System (INIS)

    Wallington, J.P.

    1999-10-01

    In this thesis, techniques of functional integration are applied to the construction of effective field theories for models of strongly correlated electrons. This is accomplished by means of the Hubbard-Stratonovic transformation which maps a system of interacting fermions onto one of free fermions interacting, not with each other, but with bosonic fields representing the collective modes of the system. Different choices of transformation are investigated throughout the thesis. It is shown that there exists a new group of discrete symmetries and transformations of the Hubbard model. Using this new group, the problem of choosing a Hubbard-Stratonovic decomposition of the Hubbard interaction term is solved. In the context of the exotic doped barium bismuthates, an extended Hubbard model with on-site attraction and nearest neighbour repulsion is studied. Mean field and renormalisation group analyses show a 'pseudospin-flop' from charge density wave to superconductivity as a function of filling. The nearest neighbour attractive Hubbard model on a quasi-2D lattice is studied as a simple phenomenological model for the high-T c cuprates. Mean field theory shows a transition from pure d-wave to pure s-wave superconductivity, via a mixed symmetry s + id state. Using Gaussian fluctuations, the BCS-Bose crossover is examined and suggestions are made about the origin of the angle dependence of the pseudogap. The continuum delta-shell potential model is introduced for anisotropic superconductors. Its mean field phases are studied and found to have some unusual properties. The BCS-Bose crossover is examined and the results are compared with those of the lattice model. Quasi-2D (highly anisotropic 3D) systems are considered. The critical properties of a Bose gas are investigated as the degree of anisotropy is varied. A new 2D Bose condensate state is found. A renormalisation group analysis is used to investigate the crossover from 2D to 3D. (author)

  11. Isolation of a solventogenic Clostridium sp. strain: fermentation of glycerol to n-butanol, analysis of the bcs operon region and its potential regulatory elements.

    Science.gov (United States)

    Panitz, J C; Zverlov, V V; Pham, V T T; Stürzl, S; Schieder, D; Schwarz, W H

    2014-02-01

    A new solventogenic bacterium, strain GT6, was isolated from standing water sediment. 16S-rRNA gene analysis revealed that GT6 belongs to the heterogeneous Clostridium tetanomorphum group of bacteria exhibiting 99% sequence identity with C. tetanomorphum 4474(T). GT6 can utilize a wide range of carbohydrate substrates including glucose, fructose, maltose, xylose and glycerol to produce mainly n-butanol without any acetone. Additional products of GT6 metabolism were ethanol, butyric acid, acetic acid, and trace amounts of 1,3-propanediol. Medium and substrate composition, and culture conditions such as pH and temperature influenced product formation. The major fermentation product from glycerol was n-butanol with a final concentration of up to 11.5 g/L. 3% (v/v) glycerol lead to a total solvent concentration of 14 g/L within 72 h. Growth was not inhibited by glycerol concentrations as high as 15% (v/v). The solventogenesis genes crt, bcd, etfA/B and hbd composing the bcs (butyryl-CoA synthesis) operon of C. tetanomorphum GT6 were sequenced. They occur in a genomic arrangement identical to those in other solventogenic clostridia. Furthermore, the sequence of a potential regulator gene highly similar to that of the NADH-sensing Rex family of regulatory genes was found upstream of the bcs operon. Potential binding sites for Rex have been identified in the promoter region of the bcs operon of solvent producing clostridia as well as upstream of other genes involved in NADH oxidation. This indicates a fundamental role of Rex in the regulation of fermentation products in anaerobic, and especially in solventogenic bacteria. Copyright © 2013 Elsevier GmbH. All rights reserved.

  12. Energy gap and upper critical field of the new magnetic superconductor Mo3Sb7 found by the Andreev reflection method

    International Nuclear Information System (INIS)

    Dmitriev, V M; Rybaltchenko, L F; Ishchenko, L A; Khristenko, E V; Bukowski, Z; Troc, R

    2006-01-01

    We present the data of the point contact (PC) Andreev-reflection measurements on the new paramagnetic superconductor Mo 3 Sb 7 , which were used for finding the energy gap Δ and upper critical field H c2 for this compound. The maximum gap value, reduced to the zero temperature via the Bardeen-Cooper-Schrieffer (BCS) theory, turned out to be Δ (0) ≅ 0.32 meV, which is slightly smaller than that expected from the BCS theory, Δ BCS (0) ≅ 0.35 meV. The temperature dependence of the gap obeys the BCS theory approximately. The H c2 (0) value of about 16.5 kOe was obtained from fitting the experimental data to the conventional H(T) dependence, which is quadratic in temperature. This value is in close agreement with the result from magnetization measurements of 17.2 kOe

  13. On the limits of consistency of Eliashberg theory and the density of states of high-Tc superconductors

    International Nuclear Information System (INIS)

    Varelogiannis, G.

    1997-01-01

    We make a detailed study of the Eliashberg theory in the coupling region where some fundamental qualitative deviations from the conventional BCS- like behavior begin to appear. These deviations are identified as the onset of a cross-over from BCS superconductivity to Bose condensation. We point out that the beginning of this cross-over occurs when the gap Δ g becomes comparable to the boson energies Ω ph . This condition traduces the physical constraint that the distance the paired electron covers during the absorption of the virtual boson, cannot be larger than the coherence length. The frontier region of couplings is of the order of λ∼3, and high-T c , materials are concerned. A clear qualitative indication of the occurrence of a cross-over regime should be a dip structure above the gap in the density of states of excitations, and this is one of the most robust characteristics of the high-T c , superconducting state. Comparing our results with tunneling and photoemission experiments we conclude that high-T c materials (cuprates and fullerides) are indeed at the beginning of a cross-over from BCS superconductivity to Bose condensation, even though the fermionic nature still prevails. If the Uemura plot is relevant, then the dip should also be present in the other materials that are close to the cross-over regime like heavy Fermion and organic superconductors. In all these materials Ginzburg Landau equations are irrelevant. (orig.)

  14. The Hall effect: An acid test for the Luttinger liquid theory of high Tc superconductors

    International Nuclear Information System (INIS)

    Anderson, P.W.

    1992-01-01

    The temperature dependence of the Hall effect has been one of the most intriguing puzzles of the 'normal' metallic state in cuprate superconductors. It is shown that the Luttinger liquid theory provides a quantitative picture of the data, in particular showing that relaxation time τ perpendicular defined by the Hall angle tan θ H ω c τ perpendicular is the relaxation rate of the spinon elementary excitations and that θ H has a simple and characteristic temperature dependence (A+BT 2 ) -1 . Observed magnitudes of θ H are incompatible with Fermi liquid theory. A discussion is added of the interlayer mechanism for superconductivity and the new form of BCS gap equation which results from it. (author). 12 refs.; 4 figs

  15. Pairing and seniority in an equations-of-motion approach to nuclear structure theory

    International Nuclear Information System (INIS)

    Covello, A.; Andreozzi, F.; Gargano, A.; Porrino, A.

    1990-01-01

    In this paper, some achievements of an equations-of-motion approach to nuclear structure theory are discussed. As an introduction to the main subject, a brief survey of some early work is given. We then describe a formalism for treating the pairing-force problem and show, by numerical appllications, that at the lowest order of approximation it provides an advantageous alternative to the BCS method. Finally, we discuss how to treat a general shell-model Hamiltonian within the framework of the seniority scheme. This makes it possible to further reduce seniority-truncated shell-model spaces, as is illustrated by examples. (orig.)

  16. Effects of particle-number-projection on nuclear moment of intertia

    International Nuclear Information System (INIS)

    Rozmej, P.

    1976-01-01

    The formalism of the moment of inertia in cranking model and BCS theory has been extended for the partially particle-number-projected BCS wave functions. The ground state moments of inertia obtained by this method are a little greater than those calculated by BCS method. A smooth growth of the moments of inertia for diminishing pairing strength constant has been obtained. (author)

  17. Theory of Fermi Liquid with Flat Bands

    Science.gov (United States)

    Khodel, V. A.

    2018-04-01

    A self-consistent theory of Fermi systems hosting flat bands is developed. Compared with an original model of fermion condensation, its key point consists in proper accounting for mixing between condensate and non-condensate degrees of freedom that leads to formation of a non-BCS gap Υ (p) in the single-particle spectrum. The results obtained explain: (1) the two-gap structure of spectra of single-particle excitations of electron systems of copper oxides, revealed in ARPES studies, (2) the role of violation of the topological stability of the Landau state in the arrangement of the T-x phase diagram of this family of high-T_c superconductors, (3) the topological nature of a metal-insulator transition, discovered in homogeneous two-dimensional low-density electron liquid of MOSFETs more than 20 years ago.

  18. Quantum structural approach to high-Tc superconductivity theory: Herzberg-Teller, Renner-Teller, Jahn-Teller effects and intervalent geminal charge transfer

    International Nuclear Information System (INIS)

    Chiu, Y.

    1997-01-01

    We use quantum molecular structure and spectroscopic thoughts of various possible vibronic interactions for the position space of two-electron geminal orbitals with Bloch sums. Our geminals have different degeneracy from one-electron molecular orbitals and are different from the momentum space of BCS free electrons. Based on Herzberg-Teller expansions, our consideration of the aspect of the Renner-Teller effect for cyclic boundary crystals (instead of the usual linear molecules) involves first-order vibronic interaction with isotope effects different from the second-order electron-phonon energy of BCS theory, bipolaron theory, etc. Our consideration of the Jahn-Teller effect with equal-minimum double-well potential leads to the intervalent charge transfer between two degenerate vibrationally affected electronic structures. Our considerations of different style vibrations other than the antisymmetric vibration for the nearest neighbor (e.g., displaced oscillator, etc.) may possibly be related to the case of special chemical structures with special doping and special coherence length. Our simple structural illustrations of such different vibronic Renner-Teller, Jahn-Teller effects and intervalent charge transfer (of La 2-x Sr x CuO 4 and YBa 2 Cu 3 O 7-x ) may promote some possible thoughts of quantum chemical structures compared and mixed with the physical treatments of special high-T c superconductors. copyright 1997 The American Physical Society

  19. Biowaiver extension potential to BCS Class III high solubility-low permeability drugs: bridging evidence for metformin immediate-release tablet.

    Science.gov (United States)

    Cheng, Ching-Ling; Yu, Lawrence X; Lee, Hwei-Ling; Yang, Chyun-Yu; Lue, Chang-Sha; Chou, Chen-Hsi

    2004-07-01

    The biopharmaceutics classification system (BCS) allows biowaiver for rapid dissolving immediate-release (IR) products of Class I drugs (high solubility and high permeability). The possibility of extending biowaivers to Class III high solubility and low permeability drugs is currently under scrutiny. In vivo bioequivalence data of different formulations of Class III drugs would support such an extension. The objective of this work was to demonstrate the bioequivalence of two marketed IR tablet products of a Class III drug, metformin hydrochloride, that are rapidly dissolving and have similar in vitro dissolution profiles. The effect of race on the systemic exposure of metformin was also explored. A randomized, open-label, two-period crossover study was conducted in 12 healthy Chinese male volunteers. Each subject received a single-dose of 500 mg of each product after an overnight fasting. The plasma concentrations of metformin were followed for 24 h. No significant formulation effect was found for the bioequivalence metrics: areas under concentration-time curve (AUC0-t, AUC0-infinity) and maximal concentration (Cmax). The 90% confidence intervals for the ratio of means were found within the acceptance range of 80-125% for the log-transformed data. Based on these results, it was concluded that the two IR products are bioequivalent. The pharmacokinetic parameters of metformin in Chinese for both products were similar and were in good agreement with those reported for metformin IR tablets in other ethnic populations. This study serves as an example for supporting biowaiver for BCS Class III drugs.

  20. Pairing in the BCS and LN approximations using continuum single particle level density

    International Nuclear Information System (INIS)

    Id Betan, R.M.; Repetto, C.E.

    2017-01-01

    Understanding the properties of drip line nuclei requires to take into account the correlations with the continuum spectrum of energy of the system. This paper has the purpose to show that the continuum single particle level density is a convenient way to consider the pairing correlation in the continuum. Isospin mean-field and isospin pairing strength are used to find the Bardeen–Cooper–Schrieffer (BCS) and Lipkin–Nogami (LN) approximate solutions of the pairing Hamiltonian. Several physical properties of the whole chain of the Tin isotope, as gap parameter, Fermi level, binding energy, and one- and two-neutron separation energies, were calculated and compared with other methods and with experimental data when they exist. It is shown that the use of the continuum single particle level density is an economical way to include explicitly the correlations with the continuum spectrum of energy in large scale mass calculation. It is also shown that the computed properties are in good agreement with experimental data and with more sophisticated treatment of the pairing interaction.

  1. BCS Theory of Hadronic Matter at High Densities

    DEFF Research Database (Denmark)

    Bohr, Henrik; Panda, Prafulla K.; Providencia, Constanca

    2012-01-01

    The equilibrium between the so-called 2SC and CFL phases of strange quark matter at high densities is investigated in the framework of a simple schematic model of the NJL type. Equal densities are assumed for quarks u, d and s. The 2SC phase is here described by a color-flavor symmetric state, in...

  2. Application of the nuclear field theory to superfluid nuclei

    International Nuclear Information System (INIS)

    Reinhardt, H.

    1980-01-01

    The quasiparticle-phonon multiplet of superfluid spherical nuclei is investigated in the framework of the nuclear field theory (NFT), using the pairing plus quadrupole force. In leading order of the NFT expansion there exists a simple relation between the energy splitting of the multiplet and the ground state B(E lambda) transitions from the multiplet. This relation states that the reduced matrix elements for the B(E lambda) transition decrease linearly with increasing energies of the multiplet states. The extent to which this relation is fulfilled by available experimental data is checked. The influence of the spurious correlations involved in the NFT treatment due to the BCS approximation is estimated. The numerical calculations are performed for 93 Nb where the ground state B(E lambda) transitions are measured for all multiplet states. (orig.)

  3. Quantum resource theory of non-stabilizer states in the one-shot regime

    Science.gov (United States)

    Ahmadi, Mehdi; Dang, Hoan; Gour, Gilad; Sanders, Barry

    Universal quantum computing is known to be impossible using only stabilizer states and stabilizer operations. However, addition of non-stabilizer states (also known as magic states) to quantum circuits enables us to achieve universality. The resource theory of non-stablizer states aims at quantifying the usefulness of non-stabilizer states. Here, we focus on a fundamental question in this resource theory in the so called single-shot regime: Given two resource states, is there a free quantum channel that will (approximately or exactly) convert one to the other?. To provide an answer, we phrase the question as a semidefinite program with constraints on the Choi matrix of the corresponding channel. Then, we use the semidefinite version of the Farkas lemma to derive the necessary and sufficient conditions for the conversion between two arbitrary resource states via a free quantum channel. BCS appreciates financial support from Alberta Innovates, NSERC, China's 1000 Talent Plan and the Institute for Quantum Information and Matter.

  4. Generalized Heine–Stieltjes and Van Vleck polynomials associated with two-level, integrable BCS models

    International Nuclear Information System (INIS)

    Marquette, Ian; Links, Jon

    2012-01-01

    We study the Bethe ansatz/ordinary differential equation (BA/ODE) correspondence for Bethe ansatz equations that belong to a certain class of coupled, nonlinear, algebraic equations. Through this approach we numerically obtain the generalized Heine–Stieltjes and Van Vleck polynomials in the degenerate, two-level limit for four cases of integrable Bardeen–Cooper–Schrieffer (BCS) pairing models. These are the s-wave pairing model, the p + ip-wave pairing model, the p + ip pairing model coupled to a bosonic molecular pair degree of freedom, and a newly introduced extended d + id-wave pairing model with additional interactions. The zeros of the generalized Heine–Stieltjes polynomials provide solutions of the corresponding Bethe ansatz equations. We compare the roots of the ground states with curves obtained from the solution of a singular integral equation approximation, which allows for a characterization of ground-state phases in these systems. Our techniques also permit the computation of the roots of the excited states. These results illustrate how the BA/ODE correspondence can be used to provide new numerical methods to study a variety of integrable systems. (paper)

  5. Theory of charge transfer at the high-Tc superconductor/electrolyte interface

    DEFF Research Database (Denmark)

    Gluzman, Sasha; Kuznetsov, Alexander M.

    1995-01-01

    , involving a gap in the electronic spectrum. The height of the hump should be much less in the case of the unconventional d-wave pairing, while the absence of the hump is a signal about the importance of pair-breaking processes typical of the strong-coupling theories or even about bipolaron (bosonic......We discuss the kinetics of electrochemical process on the high-T-c superconducting electrodes dependent on the type of superconductivity. The existence of the hump of an appreciable height in the temperature dependence of the current clearly points towards the BCS s-type superconductivity......) mechanism. Low-temperature tails at the current/temperature curve are also informative being determined by the electronic states within the gap typical of the unconventional d-wave pairing....

  6. Effects of cluster-shell competition and BCS-like pairing in 12C

    Science.gov (United States)

    Matsuno, H.; Itagaki, N.

    2017-12-01

    The antisymmetrized quasi-cluster model (AQCM) was proposed to describe α-cluster and jj-coupling shell models on the same footing. In this model, the cluster-shell transition is characterized by two parameters, R representing the distance between α clusters and Λ describing the breaking of α clusters, and the contribution of the spin-orbit interaction, very important in the jj-coupling shell model, can be taken into account starting with the α-cluster model wave function. Not only the closure configurations of the major shells but also the subclosure configurations of the jj-coupling shell model can be described starting with the α-cluster model wave functions; however, the particle-hole excitations of single particles have not been fully established yet. In this study we show that the framework of AQCM can be extended even to the states with the character of single-particle excitations. For ^{12}C, two-particle-two-hole (2p2h) excitations from the subclosure configuration of 0p_{3/2} corresponding to a BCS-like pairing are described, and these shell model states are coupled with the three α-cluster model wave functions. The correlation energy from the optimal configuration can be estimated not only in the cluster part but also in the shell model part. We try to pave the way to establish a generalized description of the nuclear structure.

  7. Scientific perspectives on extending the provision for waivers of in vivo bioavailability and bioequivalence studies for drug products containing high solubility-low permeability drugs (BCS-Class 3).

    Science.gov (United States)

    Stavchansky, Salomon

    2008-06-01

    Recently, there has been increased interest in extending the provision for waivers of in vivo bioavailability and bioequivalence (BA-BE) studies that appeared in the guidance published by the Food and Drug Administration (FDA) (1) to pharmaceutical products containing Class 3 drugs (High solubility-Low Permeability). The extension of the Biopharmaceutics Classification System (BCS) to Class 3 drugs is meritorious because of its impact on public health policy considerations. The rate limiting step in the absorption of Class 3 drugs is the permeability through the intestinal membrane. This commentary will focus its attention on the scientific considerations which need to be examined to assess the risk and the benefit prior to granting a waiver of in vivo bioavailability and/or bioequivalence studies for Class 3 drugs. It will examine the forces affecting the interconnectivity of the neuronal, immunological and hormonal systems in the gastrointestinal tract that may affect its permeability and functionality. It will also challenge the assumption that in vitro dissolution and in vitro permeability studies in tissue cultures in the presence and absence of excipients are good predictors for in vivo dissolution and in vivo permeability which are at the heart of the BCS.

  8. Fifteen years of seismic monitoring at the Las Tres Virgenes, BCS, geothermal field; Quince anos de monitoreo sismico en el campo geotermico de Las Tres Virgenes, BCS

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz Prieto, Irais; Lorenzo Pulido, Cecilia [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Morelia, Michoacan (Mexico)]. E-mail: cecilia.lorenzo@cfe.gob.mx

    2009-07-15

    Seismic monitoring at the Las Tres Virgenes, BCS, geothermal field started in 1992 with an analog station of vertical components detecting a large number of earthquakes of varying magnitudes. In February 1993, a seismic network was installed, composed of six digital stations DR-2000-with S-6000 and S-5000 sensors and three registration channels (N-S, E-W and vertical). This was the basis for the development of a program to correct arrival-time data for P and S waves due to instrument drift. From January to April 1994 and May to August 1995, based on the 170 seismic events recorded, a velocity model was proposed. From December 1995 to July 1996, seismic data were processed and interpreted, and zones of occurrence were determined for events according to magnitude and the predominant noise in the field. From September 2003 to December 2004, 10 seismic stations (permanent and temporary) were installed and monitored and it was concluded the most active fault system was El Volcan. From September to December 2004, production wells LV-4 and LV-13 were acid-stimulated and seismic monitoring during this period allowed for the definition of two important seismic zones, both related to the El Volcan fault system and to injection well LV-8. After reopening these production wells, it was concluded an increase in seismic activity had occurred. From May to August 2006, information was compiled from the seismic network and it was concluded El Partido had became the most active fault system. Presently the seismic network in this field is composed of one SARA station and four K2 units. The SARA station is telemetrically connected to the base station. [Spanish] En el campo geotermico de Las Tres Virgenes, BCS, el monitoreo sismico empezo a partir de 1992 con una sola estacion analogica de registro vertical, la cual detecto una gran cantidad de temblores de distintas magnitudes. En febrero de 1993 se instalo una red sismica con seis estaciones digitales DR-2000 con sensores S-6000 y S

  9. Theoretical and Experimental Evidence for a Nodal Energy Gap in MgB2

    Science.gov (United States)

    2017-02-17

    the larger gap, the so-called  gap, is a conventional s wave. The model is an extension of the BCS theory that accounts for the elastic anisotropy...obeys the BCS-theory textbook expression that is characterized by an exponential temperature dependence, specifically,[17,18]    2 TS RESR T R C f...that was based on measurement of the IMD [3]. Accounting for the  energy-gap contribution at higher temperatures lies outside the scope of this work

  10. Pairing induced superconductivity in holography

    Science.gov (United States)

    Bagrov, Andrey; Meszena, Balazs; Schalm, Koenraad

    2014-09-01

    We study pairing induced superconductivity in large N strongly coupled systems at finite density using holography. In the weakly coupled dual gravitational theory the mechanism is conventional BCS theory. An IR hard wall cut-off is included to ensure that we can controllably address the dynamics of a single confined Fermi surface. We address in detail the interplay between the scalar order parameter field and fermion pairing. Adding an explicitly dynamical scalar operator with the same quantum numbers as the fermion-pair, the theory experiences a BCS/BEC crossover controlled by the relative scaling dimensions. We find the novel result that this BCS/BEC crossover exposes resonances in the canonical expectation value of the scalar operator. This occurs not only when the scaling dimension is degenerate with the Cooper pair, but also with that of higher derivative paired operators. We speculate that a proper definition of the order parameter which takes mixing with these operators into account stays finite nevertheless.

  11. Bardeen-Cooper-Schrieffer universal constants generalized

    International Nuclear Information System (INIS)

    Hazaimeh, A.H.

    1992-01-01

    Weak- and moderate-coupling BCS superconductivity theory is shown to admit a more general T c formula, wherein T c approaches zero somewhat faster than with the familiar BCS T c -formula. This theory leads to a departure from the universal behavior of the gap-to-T c ratio and is consistent with some recent empirical values for exotic superconductors. This ratio is smaller than the universal BCS value of 3.53 in a way which is consistent with weak electron-boson coupling. Similarly, other universal constants related to specific heat and critical magnetic field are modified. In this dissertation, The author investigates the latter constants for weak-coupling and moderate-coupling and carry out detailed comparisons with experimental data for the cuprates and with the corresponding predictions of strong-coupling theory. This effort is to elucidate the nature of these superconductors with regards to coupling strength within an electron-boson mechanism

  12. 3-D vision and figure-ground separation by visual cortex.

    Science.gov (United States)

    Grossberg, S

    1994-01-01

    A neural network theory of three-dimensional (3-D) vision, called FACADE theory, is described. The theory proposes a solution of the classical figure-ground problem for biological vision. It does so by suggesting how boundary representations and surface representations are formed within a boundary contour system (BCS) and a feature contour system (FCS). The BCS and FCS interact reciprocally to form 3-D boundary and surface representations that are mutually consistent. Their interactions generate 3-D percepts wherein occluding and occluded object parts are separated, completed, and grouped. The theory clarifies how preattentive processes of 3-D perception and figure-ground separation interact reciprocally with attentive processes of spatial localization, object recognition, and visual search. A new theory of stereopsis is proposed that predicts how cells sensitive to multiple spatial frequencies, disparities, and orientations are combined by context-sensitive filtering, competition, and cooperation to form coherent BCS boundary segmentations. Several factors contribute to figure-ground pop-out, including: boundary contrast between spatially contiguous boundaries, whether due to scenic differences in luminance, color, spatial frequency, or disparity; partially ordered interactions from larger spatial scales and disparities to smaller scales and disparities; and surface filling-in restricted to regions surrounded by a connected boundary. Phenomena such as 3-D pop-out from a 2-D picture, Da Vinci stereopsis, 3-D neon color spreading, completion of partially occluded objects, and figure-ground reversals are analyzed. The BCS and FCS subsystems model aspects of how the two parvocellular cortical processing streams that join the lateral geniculate nucleus to prestriate cortical area V4 interact to generate a multiplexed representation of Form-And-Color-And-DEpth, or FACADE, within area V4. Area V4 is suggested to support figure-ground separation and to interact with

  13. Scientific Perspectives on Extending the Provision for Waivers of In vivo Bioavailability and Bioequivalence Studies for Drug Products Containing High Solubility-Low Permeability Drugs (BCS-Class 3)

    OpenAIRE

    Stavchansky, Salomon

    2008-01-01

    Recently, there has been increased interest in extending the provision for waivers of in vivo bioavailability and bioequivalence (BA–BE) studies that appeared in the guidance published by the Food and Drug Administration (FDA) (1) to pharmaceutical products containing Class 3 drugs (High solubility–Low Permeability). The extension of the Biopharmaceutics Classification System (BCS) to Class 3 drugs is meritorious because of its impact on public health policy considerations. The rate limiting ...

  14. Introduction to superconductivity

    CERN Document Server

    Tinkham, Michael

    1975-01-01

    Introductory survey ; the BCS theory ; magnetic properties of type I superconductors ; Ginzburg-Landau theory ; magnetic properties of type II superconductors ; Josephson effect and macroscopic quantum phenomena ; fluctuation effects ; concluding topics.

  15. Impurity dependence of superconductivity in niobium

    International Nuclear Information System (INIS)

    Laa, C.

    1984-04-01

    Jump temperatures, the critical fields Hsubc and Hsubc 2 and specific heats were measured on niobium samples where the impurity content was systematically varied by loading with nitrogen. Quantities could thus be extrapolated to lattice perfection and absolute purity. Comparisons with theories were made and some parameters extracted. Agreement was found with Gorkov theory for small impurities. A new value of the Ginsburg-Landau parameter Ko was determined to be just above 1/sqrt2 which proves that niobium is an elementary Type II semiconductor. By comparisons with the BCS and the CLAC theory the values of the mean Fermi velocity, the London penetration depth, the BCS coherence length and the impurity parameter were extracted. (G.Q.)

  16. Metabolite profiles reveal energy failure and impaired beta-oxidation in liver of mice with complex III deficiency due to a BCS1L mutation.

    Directory of Open Access Journals (Sweden)

    Heike Kotarsky

    Full Text Available BACKGROUND & AIMS: Liver is a target organ in many mitochondrial disorders, especially if the complex III assembly factor BCS1L is mutated. To reveal disease mechanism due to such mutations, we have produced a transgenic mouse model with c.232A>G mutation in Bcs1l, the causative mutation for GRACILE syndrome. The homozygous mice develop mitochondrial hepatopathy with steatosis and fibrosis after weaning. Our aim was to assess cellular mechanisms for disease onset and progression using metabolomics. METHODS: With mass spectrometry we analyzed metabolite patterns in liver samples obtained from homozygotes and littermate controls of three ages. As oxidative stress might be a mechanism for mitochondrial hepatopathy, we also assessed H(2O(2 production and expression of antioxidants. RESULTS: Homozygotes had a similar metabolic profile at 14 days of age as controls, with the exception of slightly decreased AMP. At 24 days, when hepatocytes display first histopathological signs, increases in succinate, fumarate and AMP were found associated with impaired glucose turnover and beta-oxidation. At end stage disease after 30 days, these changes were pronounced with decreased carbohydrates, high levels of acylcarnitines and amino acids, and elevated biogenic amines, especially putrescine. Signs of oxidative stress were present in end-stage disease. CONCLUSIONS: The findings suggest an early Krebs cycle defect with increases of its intermediates, which might play a role in disease onset. During disease progression, carbohydrate and fatty acid metabolism deteriorate leading to a starvation-like condition. The mouse model is valuable for further investigations on mechanisms in mitochondrial hepatopathy and for interventions.

  17. Equation for the superfluid gap obtained by coarse graining the Bogoliubov-de Gennes equations throughout the BCS-BEC crossover

    Science.gov (United States)

    Simonucci, S.; Strinati, G. C.

    2014-02-01

    We derive a nonlinear differential equation for the gap parameter of a superfluid Fermi system by performing a suitable coarse graining of the Bogoliubov-de Gennes (BdG) equations throughout the BCS-BEC crossover, with the aim of replacing the time-consuming solution of the original BdG equations by the simpler solution of this novel equation. We perform a favorable numerical test on the validity of this new equation over most of the temperature-coupling phase diagram, by an explicit comparison with the full solution of the original BdG equations for an isolated vortex. We also show that the new equation reduces both to the Ginzburg-Landau equation for Cooper pairs in weak coupling close to the critical temperature and to the Gross-Pitaevskii equation for composite bosons in strong coupling at low temperature.

  18. Theory of RF superconductivity for resonant cavities

    Science.gov (United States)

    Gurevich, Alex

    2017-03-01

    An overview of a theory of electromagnetic response of superconductors in strong radio-frequency (RF) electromagnetic fields is given with the emphasis on applications to superconducting resonant cavities for particle accelerators. The paper addresses fundamentals of the BCS surface resistance, the effect of subgap states and trapped vortices on the residual surface resistance at low RF fields, and a nonlinear surface resistance at strong fields, particularly the effect of the RF field suppression of the surface resistance. These issues are essential for the understanding of the field dependence of high quality factors Q({B}a)˜ {10}10{--}{10}11 achieved on the Nb cavities at 1.3-2 K in strong RF fields B a close to the depairing limit, and the extended Q({B}a) rise which has been observed on Ti and N-treated Nb cavities. Possible ways of further increase of Q({B}a) and the breakdown field by optimizing impurity concentration at the surface and by multilayer nanostructuring with materials other than Nb are discussed.

  19. Evaluation of Single Nucleotide Polymorphisms (SNPs) in the p53 Binding Protein 1 (TP53BP1) Gene in Breast Cancer Patients Treated With Breast-Conserving Surgery and Whole-Breast Irradiation (BCS + RT)

    International Nuclear Information System (INIS)

    Haffty, Bruce G.; Goyal, Sharad; Kulkarni, Diptee; Green, Camille; Vazquez, Alexi; Schiff, Devora; Moran, Meena S.; Yang Qifeng; Ganesan, Shridar; Hirsfield, Kim M.

    2011-01-01

    Purpose: TP53BP1 is a key component of radiation-induced deoxyribonucleic acid damage repair. The purpose of this study was to evaluate the significance of a known common single nucleotide polymorphism in this gene (rs560191) in patients treated with breast-conserving surgery and whole-breast irradiation (BCS + RT). Methods and Materials: The population consisted of 176 premenopausal women treated with BCS + RT (median follow-up, 12 years). Genomic deoxyribonucleic acid was processed by use of TaqMan assays. Each allele for rs560191 was either C or G, so each patient was therefore classified as CC, CG, or GG. Patients were grouped as GG if they were homozygous for the variant G allele or CC-CG if they carried at least one copy of the common C allele (CC or CG). Results: Of the 176 women, 124 (71%) were CC-CG and 52 (29%) were GG. The mean age was 44 years for GG vs. 38 years for CC-CG (p < 0.001). GG was more common in African-American women than white women (69% vs. 13%, p < 0.001) and more commonly estrogen receptor negative (70% vs. 49%, p = 0.02). There were no significant correlations of rs560191 with other critical variables. Despite the fact that GG patients were older, the 10-year rate of local relapses was higher (22% for GG vs. 12% for CC-CG, p = 0.04). Conclusions: This novel avenue of investigation of polymorphisms in radiation repair/response genes in patients treated with BCS + RT suggests a correlation to local relapse. Additional evaluation is needed to assess the biological and functional significance of these single nucleotide polymorphisms, and larger confirmatory validation studies will be required to determine the clinical implications.

  20. Odd-even mass differences from self-consistent mean field theory

    International Nuclear Information System (INIS)

    Bertsch, G. F.; Bertulani, C. A.; Nazarewicz, W.; Schunck, N.; Stoitsov, M. V.

    2009-01-01

    We survey odd-even nuclear binding energy staggering using density functional theory with several treatments of the pairing interaction including the BCS, Hartree-Fock-Bogoliubov, and the Hartree-Fock-Bogoliubov with the Lipkin-Nogami approximation. We calculate the second difference of binding energies and compare the results with 443 measured neutron energy differences in isotope chains and 418 measured proton energy differences in isotone chains. The particle-hole part of the energy functional is taken as the SLy4 Skyrme parametrization, and the pairing part of the functional is based on a contact interaction with possible density dependence. An important feature of the data, reproduced by the theory, is the sharp gap quenching at magic numbers. With the strength of the interaction as a free parameter, the theory can reproduce the data to an rms accuracy of about 0.25 MeV. This is slightly better than a single-parameter phenomenological description but slightly poorer than the usual two-parameter phenomenological form c/A α . The following conclusions can be made about the performance of common parametrization of the pairing interaction: (i) there is a weak preference for a surface-peaked neutron-neutron pairing, which might be attributable to many-body effects, (ii) a larger strength is required in the proton pairing channel than in the neutron pairing channel, and (iii) pairing strengths adjusted to the well-known spherical isotope chains are too weak to give a good overall fit to the mass differences

  1. Relativistic mean field theory with density dependent coupling constants for nuclear matter and finite nuclei with large charge asymmetry

    Energy Technology Data Exchange (ETDEWEB)

    Typel, S; Wolter, H H [Sektion Physik, Univ. Muenchen, Garching (Germany)

    1998-06-01

    Nuclear matter and ground state properties for (proton and neutron) semi-closed shell nuclei are described in relativistic mean field theory with coupling constants which depend on the vector density. The parametrization of the density dependence for {sigma}-, {omega}- and {rho}-mesons is obtained by fitting to properties of nuclear matter and some finite nuclei. The equation of state for symmetric and asymmetric nuclear matter is discussed. Finite nuclei are described in Hartree approximation, including a charge and an improved center-of-mass correction. Pairing is considered in the BCS approximation. Special attention is directed to the predictions for properties at the neutron and proton driplines, e.g. for separation energies, spin-orbit splittings and density distributions. (orig.)

  2. Investigation of the effect of solubility increase at the main absorption site on bioavailability of BCS class II drug (risperidone) using liquisolid technique.

    Science.gov (United States)

    Khames, Ahmed

    2017-11-01

    BCS class II drugs usually suffer inadequate bioavailability as dissolution step is the absorption rate limiting step. In this work, the effect of solubility increase at the main absorption site for these drugs was investigated using risperidone as a drug model. Liquisolid technique was applied to prepare risperidone per-oral tablets of high dissolution rate at intestinal pH (6.8) using versatile nonionic surfactants of high solubilizing ability [Transcutol HP, Labrasol and Labrasol/Labrafil (1:1) mixture] as liquid vehicles at different drug concentrations (10-30%) and fixed (R). The prepared liquisolid tablets were fully evaluated and the dissolution rate at pH 6.8 was investigated. The formulae that showed significantly different release rate were selected and subjected to mathematical modeling using DE 25 , MDT and similarity factor (f2). Depending on mathematical modeling results, formula of higher dissolution rate was subjected to solid state characterization using differential scanning calorimetric (DSC), infrared spectroscopy (IR) and X-ray diffraction (XRD). Finally, the drug bioavailability was studied in comparison to conventional tablets in rabbits. Results showed that liquisolid tablet prepared using Labrasol/Labrafil (1:1) mixture as liquid vehicle containing 10% risperidone is a compatible formula with law drug crystallinity and higher dissolution rate (100% in 25 min). The drug bioavailability was significantly increased in comparison to the conventional tablets (1441.711 μg h/mL and 137.518 μg/mL in comparison to 321.011 μg h/mL and 38.673 μg/mL for AUC and Cp max , respectively). This led to the conclusion that liquisolid technique was efficiently improved drug solubility and solubility increase of BCS class II drugs at their main absorption site significantly increases their bioavailability.

  3. In Vitro, in Silico, and in Vivo Assessments of Intestinal Precipitation and Its Impact on Bioavailability of a BCS Class 2 Basic Compound.

    Science.gov (United States)

    Kou, Dawen; Zhang, Chen; Yiu, Hiuwing; Ng, Tania; Lubach, Joseph W; Janson, Matthew; Mao, Chen; Durk, Matthew; Chinn, Leslie; Winter, Helen; Wigman, Larry; Yehl, Peter

    2018-04-02

    In this study, a multipronged approach of in vitro experiments, in silico simulations, and in vivo studies was developed to evaluate the dissolution, supersaturation, precipitation, and absorption of three formulations of Compound-A, a BCS class 2 weak base with pH-dependent solubility. In in vitro 2-stage dissolution experiments, the solutions were highly supersaturated with no precipitation at the low dose but increasing precipitation at higher doses. No difference in precipitation was observed between the capsules and tablets. The in vitro precipitate was found to be noncrystalline with higher solubility than the crystalline API, and was readily soluble when the drug concentration was lowered by dilution. A gastric transit and biphasic dissolution (GTBD) model was developed to better mimic gastric transfer and intestinal absorption. Precipitation was also observed in GTBD, but the precipitate redissolved and partitioned into the organic phase. In vivo data from the phase 1 clinical trial showed linear and dose proportional PK for the formulations with no evidence of in vivo precipitation. While the in vitro precipitation observed in the 2-stage dissolution appeared to overestimate in vivo precipitation, the GTBD model provided absorption profiles consistent with in vivo data. In silico simulation of plasma concentrations by GastroPlus using biorelevant in vitro dissolution data from the tablets and capsules and assuming negligible precipitation was in line with the observed in vivo profiles of the two formulations. The totality of data generated with Compound-A indicated that the bioavailability differences among the three formulations were better explained by the differences in gastric dissolution than intestinal precipitation. The lack of intestinal precipitation was consistent with several other BCS class 2 basic compounds in the literature for which highly supersaturated concentrations and rapid absorption were also observed.

  4. Tc, 2Δ0/KBTc and parameters of phonon spectrum for amorphous superconductors

    International Nuclear Information System (INIS)

    Cao Xiaowen

    1987-04-01

    After the correlations between superconducting parameters T C and 2Δ 0 , the parameters of the phonon spectrum, λ, , 2 > and Hall coefficient R H and between the superconducting T C and the parameters of the phonon spectrum ω 0 and /ω 0 were researched analytically. It had been found that there is a maximum of the above-mentioned both superconducting and the phonon spectrum parameters in the region of R H = -3.5 to -4.0 x 10 -11 m 3 /AS and that the materials having high ω 0 is favourable to obtain amorphous superconductors with high T C as well as that the relation between T C and the degree of the lattice disorder (i.e. /ω 0 value) is linear. On the basis of the above-mentioned results, a formula of T C and 2Δ 0 /k B T C of amorphous superconductors had been given. According to both proposed formula, it is noted for the first time that amorphous superconductor of the non-transition metals and their alloys is either a typical strong coupling superconductor which has a much larger 2 Δ 0 /k B T C than BCS theory or a extreme weak coupling superconductor which has a much smaller 2 Δ 0 /k B T C than BCS theory. Of coures, they can be also a weak coupling superconductor whose 2 Δ 0 /k B T C is consistent with BCS theory or approximate to one. The reason that the measurement value of 2 Δ 0 /k BTC of the weak coupling superconductors in the crystal state deviates obviously from BCS theory has been explained

  5. Two-fluid model of the superconductivity in the BCS's theory

    International Nuclear Information System (INIS)

    Rangelov, J.

    1977-01-01

    The coefficients of Bogolubov-Valatin's transformation are chosen in accordance with the two-fluid model of superconductivity. The energy spectrum of superconducting quasi-particles is obtained as a solution of the linearized equation of motion of interacting particles. The energy distribution of the superconducting and normal quasi-particles is discussed from a new view-point. The correlation between the quasi-particles forming the Cooper's pair is discussed in accordance with the proposed ideas. The tunnelling of the normal quasi-particles in systems M-I-S and S 1 -I-S 2 is investigated qualitatively

  6. Theory of superconductivity with non-Hermitian and parity-time reversal symmetric Cooper pairing symmetry

    Science.gov (United States)

    Ghatak, Ananya; Das, Tanmoy

    2018-01-01

    Recently developed parity (P ) and time-reversal (T ) symmetric non-Hermitian systems govern a rich variety of new and characteristically distinct physical properties, which may or may not have a direct analog in their Hermitian counterparts. We study here a non-Hermitian, PT -symmetric superconducting Hamiltonian that possesses a real quasiparticle spectrum in the PT -unbroken region of the Brillouin zone. Within a single-band mean-field theory, we find that real quasiparticle energies are possible when the superconducting order parameter itself is either Hermitian or anti-Hermitian. Within the corresponding Bardeen-Cooper-Schrieffer (BCS) theory, we find that several properties are characteristically distinct and novel in the non-Hermitian pairing case than its Hermitian counterpart. One of our significant findings is that while a Hermitian superconductor gives a second-order phase transition, the non-Hermitian one produces a robust first-order phase transition. The corresponding thermodynamic properties and the Meissner effect are also modified accordingly. Finally, we discuss how such a PT -symmetric pairing can emerge from an antisymmetric potential, such as the Dzyloshinskii-Moriya interaction, but with an external bath, or complex potential, among others.

  7. Lipid Based Formulations of Biopharmaceutics Classification System (BCS Class II Drugs: Strategy, Formulations, Methods and Saturation

    Directory of Open Access Journals (Sweden)

    Šoltýsová I.

    2016-12-01

    Full Text Available Active ingredients in pharmaceuticals differ by their physico-chemical properties and their bioavailability therefore varies. The most frequently used and most convenient way of administration of medicines is oral, however many drugs are little soluble in water. Thus they are not sufficiently effective and suitable for such administration. For this reason a system of lipid based formulations (LBF was developed. Series of formulations were prepared and tested in water and biorelevant media. On the basis of selection criteria, there were selected formulations with the best emulsification potential, good dispersion in the environment and physical stability. Samples of structurally different drugs included in the Class II of the Biopharmaceutics classification system (BCS were obtained, namely Griseofulvin, Glibenclamide, Carbamazepine, Haloperidol, Itraconazol, Triclosan, Praziquantel and Rifaximin, for testing of maximal saturation in formulations prepared from commercially available excipients. Methods were developed for preparation of formulations, observation of emulsification and its description, determination of maximum solubility of drug samples in the respective formulation and subsequent analysis. Saturation of formulations with drugs showed that formulations 80 % XA and 20 % Xh, 35 % XF and 65 % Xh were best able to dissolve the drugs which supports the hypothesis that it is desirable to identify limited series of formulations which could be generally applied for this purpose.

  8. Microscopic Derivation of the Ginzburg-Landau Model

    DEFF Research Database (Denmark)

    Frank, Rupert; Hainzl, Christian; Seiringer, Robert

    2014-01-01

    We present a summary of our recent rigorous derivation of the celebrated Ginzburg-Landau (GL) theory, starting from the microscopic Bardeen-Cooper-Schrieffer (BCS) model. Close to the critical temperature, GL arises as an effective theory on the macroscopic scale. The relevant scaling limit...

  9. Verification of an analytic fit for the vortex core profile in superfluid Fermi gases

    International Nuclear Information System (INIS)

    Verhelst, Nick; Klimin, Serghei; Tempere, Jacques

    2017-01-01

    Highlights: • The vortex profile in an imbalanced Fermi condensate is investigated. • The analytic fit for the vortex profile is compared with numerical simulations. • The analytic fit excellently agrees with numeric results in the BCS-BEC crossover. - Abstract: A characteristic property of superfluidity and -conductivity is the presence of quantized vortices in rotating systems. To study the BEC-BCS crossover the two most common methods are the Bogoliubov-De Gennes theory and the usage of an effective field theory. In order to simplify the calculations for one vortex, it is often assumed that the hyperbolic tangent yields a good approximation for the vortex structure. The combination of a variational vortex structure, together with cylindrical symmetry yields analytic (or numerically simple) expressions. The focus of this article is to investigate to what extent this analytic fit truly reflects the vortex structure throughout the BEC-BCS crossover at finite temperatures. The vortex structure will be determined using the effective field theory presented in [Eur. Phys. Journal B 88, 122 (2015)] and compared to the variational analytic solution. By doing this it is possible to see where these two structures agree, and where they differ. This comparison results in a range of applicability where the hyperbolic tangent will be a good fit for the vortex structure.

  10. Verification of an analytic fit for the vortex core profile in superfluid Fermi gases

    Energy Technology Data Exchange (ETDEWEB)

    Verhelst, Nick, E-mail: nick.verhelst@uantwerpen.be [TQC, Universiteit Antwerpen, Universiteitsplein 1, B-2610 Antwerpen (Belgium); Klimin, Serghei, E-mail: sergei.klimin@uantwerpen.be [TQC, Universiteit Antwerpen, Universiteitsplein 1, B-2610 Antwerpen (Belgium); Department of Theoretical Physics, State University of Moldova, Republic of Moldova (Moldova, Republic of); Tempere, Jacques [TQC, Universiteit Antwerpen, Universiteitsplein 1, B-2610 Antwerpen (Belgium); Lyman Laboratory of Physics, Harvard University (United States)

    2017-02-15

    Highlights: • The vortex profile in an imbalanced Fermi condensate is investigated. • The analytic fit for the vortex profile is compared with numerical simulations. • The analytic fit excellently agrees with numeric results in the BCS-BEC crossover. - Abstract: A characteristic property of superfluidity and -conductivity is the presence of quantized vortices in rotating systems. To study the BEC-BCS crossover the two most common methods are the Bogoliubov-De Gennes theory and the usage of an effective field theory. In order to simplify the calculations for one vortex, it is often assumed that the hyperbolic tangent yields a good approximation for the vortex structure. The combination of a variational vortex structure, together with cylindrical symmetry yields analytic (or numerically simple) expressions. The focus of this article is to investigate to what extent this analytic fit truly reflects the vortex structure throughout the BEC-BCS crossover at finite temperatures. The vortex structure will be determined using the effective field theory presented in [Eur. Phys. Journal B 88, 122 (2015)] and compared to the variational analytic solution. By doing this it is possible to see where these two structures agree, and where they differ. This comparison results in a range of applicability where the hyperbolic tangent will be a good fit for the vortex structure.

  11. Pairing phase transition and thermodynamical quantities in 148,149Sm

    International Nuclear Information System (INIS)

    Razavi, R.; Behkami, A.N.; Dehghani, V.

    2014-01-01

    The nuclear level densities and entropies in 148,149 Sm have been calculated in the framework of the superconducting theory that includes modified nuclear pairing gap. For modified pairing gap parameter the smooth transition from the BCS to the Fermi type distributions is used. By applying modified pairing gap, the extracted S-shaped heat capacity as a function of nuclear temperature exhibits a physical and smoother behavior instead of the singular behavior predicted by the BCS equations at critical temperature

  12. Experimental First Order Pairing Phase Transition in Atomic Nuclei

    International Nuclear Information System (INIS)

    Moretto, L G; Larsen, A C; Giacoppo, F; Guttormsen, M; Siem, S

    2015-01-01

    The natural log of experimental nuclear level densities at low energy is linear with energy. This can be interpreted in terms of a nearly 1st order phase transition from a superfluid to an ideal gas of quasi particles. The transition temperature coincides with the BCS critical temperature and yields gap parameters in good agreement with the values extracted from even- odd mass differences from rotational states. This converging evidence supports the relevance of the BCS theory to atomic nuclei

  13. Solubility enhancement of BCS Class II drug by solid phospholipid dispersions: Spray drying versus freeze-drying.

    Science.gov (United States)

    Fong, Sophia Yui Kau; Ibisogly, Asiye; Bauer-Brandl, Annette

    2015-12-30

    The poor aqueous solubility of BCS Class II drugs represents a major challenge for oral dosage form development. Using celecoxib (CXB) as model drug, the current study adopted a novel solid phospholipid nanoparticle (SPLN) approach and compared the effect of two commonly used industrial manufacturing methods, spray- and freeze-drying, on the solubility and dissolution enhancement of CXB. CXB was formulated with Phospholipoid E80 (PL) and trehalose at different CXB:PL:trehalose ratios, of which 1:10:16 was the optimal formulation. Spherical amorphous SPLNs with average diameters <1μm were produced by spray-drying; while amorphous 'matrix'-like structures of solid PL dispersion with larger particle sizes were prepared by freeze-drying. Formulations from both methods significantly enhanced the dissolution rates, apparent solubility, and molecularly dissolved concentration of CXB in phosphate buffer (PBS, pH 6.5) and in biorelevant fasted state simulated intestinal fluid (FaSSIF, pH 6.5) (p<0.05). While similar dissolution rates were found, the spray-dried SPLNs had a larger enhancement in apparent solubility (29- to 132-fold) as well as molecular solubility (18-fold) of CXB at equilibrium (p<0.05). The strong capability of the spray-dried SPLNs to attain 'true' supersaturation state makes them a promising approach for bioavailability enhancement of poorly soluble drugs. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Simultaneous projection of particle-number and angular momentum BCS wave-functions in the rare-earth nuclei

    International Nuclear Information System (INIS)

    Oudih, M.R.; Fellah, M.; Allal, N.H.; Benhamouda, N.

    1999-01-01

    It is well established that the BCS wave-functions are neither eigen-functions of the particle-number operator nor of the angular momentum operator. In a previous paper, we have developed a particle-number projection before variation method (of FBCS type). This discrete projection method is based on the SBCS wave-function. The aim of the present contribution is to perform a subsequent angular momentum projection by means of the Peierls-Yoccoz method. The general expression of the system energy, after the double projection, is established in the case of axial symmetry. For practical calculations, an approximation method is introduced. It leads to a semi-classical form of the rotational energy. The rotational spectra have been evaluated numerically for some even-even rare-earth nuclei. The single-particle energies and eigen-states are those of a deformed Woods-Saxon mean field. The obtained results are compared on one hand, to the experimental data, and on the other hand, to the theoretical spectra evaluated by a particle-number projection after variation method (of PBCS type). For all studied nuclei, the spectra determined by the FBCS method reproduce the experimental data better than those of the PBCS method. However, even if the present method is satisfying for low angular momenta, the agreement with the experimental data is lesser for I ≥ 8, particularly for the lighter studied nuclei. (authors)

  15. Evaluación rural participativa: uso de los recursos naturales en la reserva de la biosfera El Vizcaíno, BCS, México

    Directory of Open Access Journals (Sweden)

    Magdalena Lagunas-Vázquez

    2008-01-01

    Full Text Available En este artículo se describe la experiencia de investigación participativa donde se destaca la importancia de la vinculación entre los actores sociales (en este caso de áreas rurales protegidas, el sector académico y las organizaciones no gubernamentales. Se analizan los resultados de una evaluación rural participativa (ERP llevada a cabo en la Reserva de la Biosfera El Vizcaíno, BCS, México. Además de identificar lo que los actores sociales perciben como problemas y las formas en que proponen vías de solución, se logró obtener información acerca del uso de los recursos naturales por parte de los residentes de las comunidades y se formuló un plan comunitario de uso de los mismos.

  16. Advantageous Solubility-Permeability Interplay When Using Amorphous Solid Dispersion (ASD) Formulation for the BCS Class IV P-gp Substrate Rifaximin: Simultaneous Increase of Both the Solubility and the Permeability.

    Science.gov (United States)

    Beig, Avital; Fine-Shamir, Noa; Lindley, David; Miller, Jonathan M; Dahan, Arik

    2017-05-01

    Rifaximin is a BCS class IV (low-solubility, low-permeability) drug and also a P-gp substrate. The aims of this work were to assess the efficiency of different rifaximin amorphous solid dispersion (ASDs) formulations in achieving and maintaining supersaturation and to investigate the consequent solubility-permeability interplay. Spray-dried rifaximin ASDs were prepared with different hydrophilic polymers and their ability to achieve and maintain supersaturation was assessed. Then, rifaximin's apparent intestinal permeability was investigated as a function of increasing supersaturation both in vitro using the parallel artificial membrane permeability assay (PAMPA) and in vivo using the single-pass rat intestinal perfusion (SPIP) model. The efficiency of the different ASDs to achieve and maintain supersaturation of rifaximin was found to be highly polymer dependent, and the copovidone/HPC-SL formulation was found to be superior to the other two, allowing supersaturation of 200× that of the crystalline solubility for 20 h. In vitro, rifaximin flux was increased and the apparent permeability was constant as a function of increasing supersaturation level. In vivo, on the other hand, absorption rate coefficient (k a ) was first constant as a function of increasing supersaturation, but at 250×, the crystalline solubility k a was doubled, similar to the k a in the presence of the strong P-gp inhibitor GF120918. In conclusion, a new and favorable nature of solubility-permeability interplay was revealed in this work: delivering high supersaturation level of the BCS class IV drug rifaximin via ASD, thereby saturating the drugs' P-gp-mediated efflux transport, led to the favorable unique win-win situation, where both the solubility and the permeability increased simultaneously.

  17. Boson exchange mechanisms, bounds and asymptotic limits

    International Nuclear Information System (INIS)

    Carbotte, J.P.; Marsiglio, F.

    1989-01-01

    BCS theory predicts universal laws for the normalized thermodynamic and other properties of superconductors. The only parameter in the theory, which models the pairing interaction, can be fit to the measured size of the critical temperature and everything else follows. For example, the ratio of twice the gap edge Δ o to the critical temperature is 3.54 while the specific heat jump at T c (ΔC(T c )) normalized to the normal state value of the electronic specific heat γ o T c (with γ o the Sommerfeld constant) is 1.43. Other universal numbers also apply. In real materials, deviations from BCS laws are observed 2 - 6 which carry information on details of the microscopic parameters involved that cannot be modeled well by a constant pairing potential approximation

  18. Superconductivity in the elements, alloys and simple compounds

    Energy Technology Data Exchange (ETDEWEB)

    Webb, G.W. [Department of Physics, University of California, San Diego, La Jolla, CA 92093-0319 (United States); Marsiglio, F. [Department of Physics, University of Alberta, Edmonton, Alberta, Canada T6G 2E1 (Canada); Hirsch, J.E., E-mail: jhirsch@ucsd.edu [Department of Physics, University of California, San Diego, La Jolla, CA 92093-0319 (United States)

    2015-07-15

    Highlights: • A review of superconductivity in elements, alloys and simple compounds is given. • These materials are believed to be described by BCS–Eliashberg theory. • The McMillan–Rowell inversion process is described. • Calculations of Tc’s from first principles are surveyed. • Other criteria beyond BCS to characterize these superconductors are discussed. - Abstract: We give a brief review of superconductivity at ambient pressure in elements, alloys, and simple three-dimensional compounds. Historically these were the first superconducting materials studied, and based on the experimental knowledge gained from them the BCS theory of superconductivity was developed in 1957. Extended to include the effect of phonon retardation, the theory is believed to describe the subset of superconducting materials known as ‘conventional superconductors’, where superconductivity is caused by the electron–phonon interaction. These include the elements, alloys and simple compounds discussed in this article and several other classes of materials discussed in other articles in this Special Issue.

  19. Superconductivity in the elements, alloys and simple compounds

    International Nuclear Information System (INIS)

    Webb, G.W.; Marsiglio, F.; Hirsch, J.E.

    2015-01-01

    Highlights: • A review of superconductivity in elements, alloys and simple compounds is given. • These materials are believed to be described by BCS–Eliashberg theory. • The McMillan–Rowell inversion process is described. • Calculations of Tc’s from first principles are surveyed. • Other criteria beyond BCS to characterize these superconductors are discussed. - Abstract: We give a brief review of superconductivity at ambient pressure in elements, alloys, and simple three-dimensional compounds. Historically these were the first superconducting materials studied, and based on the experimental knowledge gained from them the BCS theory of superconductivity was developed in 1957. Extended to include the effect of phonon retardation, the theory is believed to describe the subset of superconducting materials known as ‘conventional superconductors’, where superconductivity is caused by the electron–phonon interaction. These include the elements, alloys and simple compounds discussed in this article and several other classes of materials discussed in other articles in this Special Issue

  20. Study of bubble structure in N = 20 isotones within relativistic mean-field plus BCS approach

    International Nuclear Information System (INIS)

    Kumawat, M.; Singh, U.K.; Jain, S.K.; Saxena, G.; Aggarwal, Mamta; Singh, S. Somorendro; Kaushik, M.

    2017-01-01

    Guided by various theoretical studies and encouraged with recent first experimental evidence of proton density depletion in "3"4Si, we have applied relativistic mean field plus BCS approach for systematic study of bubble structure in magic nuclei with N = 20 isotones. Our present investigations include single particle energies, deformations, separation energies as well as neutron and proton densities etc. It is found that proton sd shells (1d_5_/_2,2s_1_/_2,1d_3_/_2) in N = 20 isotones play very important role in the formation of bubble structure. The unoccupied 2s_1_/_2 state gives rise to bubble since this 2s_1_/_2 state does not have any centrifugal barrier, therefore for Z = 8 - 14 in the isotonic chain radial distributions of such state is found with peak in the interior of the nucleus with corresponding wave functions extending into the surface region. Consequently, in these nuclei with unoccupied s-state the central density found depleted as compared to the nucleus wherein this state is fully occupied. It is important to note here that in these nuclei depletion in proton density for "3"4Si is found with most significance which is in accord with the recent experiment. Moving further for higher Z value, Z = 16 and Z = 18 the 2s_1_/_2 state remains semi-occupied and contributing partially in the depletion of central density resulting semi-bubble structure for Z = 16 and 18. For Z≥20, 2s_1_/_2 state get fully occupied and no sign of bubble structures are seen for higher isotones

  1. Shear viscosity and imperfect fluidity in bosonic and fermionic superfluids

    Science.gov (United States)

    Boyack, Rufus; Guo, Hao; Levin, K.

    2014-12-01

    In this paper we address the ratio of the shear viscosity to entropy density η /s in bosonic and fermionic superfluids. A small η /s is associated with nearly perfect fluidity, and more general measures of the fluidity perfection/imperfection are of wide interest to a number of communities. We use a Kubo approach to concretely address this ratio via low-temperature transport associated with the quasiparticles. Our analysis for bosonic superfluids utilizes the framework of the one-loop Bogoliubov approximation, whereas for fermionic superfluids we apply BCS theory and its BCS-BEC extension. Interestingly, we find that the transport properties of strict BCS and Bogoliubov superfluids have very similar structures, albeit with different quasiparticle dispersion relations. While there is a dramatic contrast between the power law and exponential temperature dependence for η alone, the ratio η /s for both systems is more similar. Specifically, we find the same linear dependence (on the ratio of temperature T to inverse lifetime γ (T ) ) with η /s ∝T /γ (T ) , corresponding to imperfect fluidity. By contrast, near the unitary limit of BCS-BEC superfluids a very different behavior results, which is more consistent with near-perfect fluidity.

  2. Induced interactions in a superfluid Bose-Fermi mixture

    DEFF Research Database (Denmark)

    Kinnunen, Jami; Bruun, Georg

    2015-01-01

    We analyze a Bose-Einstein condensate (BEC) mixed with a superfluid two-component Fermi gas in the whole BCS-BEC crossover. Using a quasiparticle random-phase approximation combined with Beliaev theory to describe the Fermi superfluid and the BEC, respectively, we show that the single-particle an......We analyze a Bose-Einstein condensate (BEC) mixed with a superfluid two-component Fermi gas in the whole BCS-BEC crossover. Using a quasiparticle random-phase approximation combined with Beliaev theory to describe the Fermi superfluid and the BEC, respectively, we show that the single...... shift in the excitation spectrum of the BEC. In addition, the excitation of quasiparticles in the Fermi superfluid leads to damping of the excitations in the BEC. Besides studying induced interactions themselves, we can use these prominent effects to systematically probe the strongly interacting Fermi...

  3. Two-body correlation functions in dilute nuclear matter

    International Nuclear Information System (INIS)

    Isayev, A A

    2006-01-01

    Finding the distinct features of the crossover from the regime of large overlapping Cooper pairs to the limit of non-overlapping pairs of fermions (Shafroth pairs) in multicomponent Fermi systems remains one of the actual problems in a quantum many-body theory. Here this transition is studied by calculating the two-body density, spin and isospin correlation functions in dilute asymmetric nuclear matter. It is shown that criterion of the crossover (Phys. Rev. Lett. 95, 090402 (2005)), consisting in the change of the sign of the density correlation function at low momentum transfer, fails to describe correctly the density-driven BEC-BCS transition at finite isospin asymmetry or finite temperature. As an unambiguous signature of the BEC-BCS transition, there can be used the presence (BCS regime) or absence (BEC regime) of the singularity in the momentum distribution of the quasiparticle density of states

  4. Possible superconductivity in the Bismuth IV solid phase under pressure.

    Science.gov (United States)

    Valladares, Ariel A; Rodríguez, Isaías; Hinojosa-Romero, David; Valladares, Alexander; Valladares, Renela M

    2018-04-13

    The first successful theory of superconductivity was the one proposed by Bardeen, Cooper and Schrieffer in 1957. This breakthrough fostered a remarkable growth of the field that propitiated progress and questionings, generating alternative theories to explain specific phenomena. For example, it has been argued that Bismuth, being a semimetal with a low number of carriers, does not comply with the basic hypotheses underlying BCS and therefore a different approach should be considered. Nevertheless, in 2016 based on BCS we put forth a prediction that Bi at ambient pressure becomes a superconductor at 1.3 mK. A year later an experimental group corroborated that in fact Bi is a superconductor with a transition temperature of 0.53 mK, a result that eluded previous work. So, since Bi is superconductive in almost all the different structures and phases, the question is why Bi-IV has been elusive and has not been found yet to superconduct? Here we present a study of the electronic and vibrational properties of Bi-IV and infer its possible superconductivity using a BCS approach. We predict that if the Bi-IV phase structure were cooled down to liquid helium temperatures it would also superconduct at a T c of 4.25 K.

  5. 32nd Annual Conference of the Gesellschaft für Klassifikation e.V., Joint Conference with the British Classification Society (BCS) and the Dutch/Flemish Classification Society (VOC), Helmut-Schmidt-University

    CERN Document Server

    Lausen, Berthold; Seidel, Wilfried; Ultsch, Alfred

    2010-01-01

    Data Analysis, Data Handling and Business Intelligence are research areas at the intersection of computer science, artificial intelligence, mathematics, and statistics. They cover general methods and techniques that can be applied to a vast set of applications such as in marketing, finance, economics, engineering, linguistics, archaeology, musicology, medical science, and biology. This volume contains the revised versions of selected papers presented during the 32nd Annual Conference of the German Classification Society (Gesellschaft für Klassifikation, GfKl). The conference, which was organized in cooperation with the British Classification Society (BCS) and the Dutch/Flemish Classification Society (VOC), was hosted by Helmut-Schmidt-University, Hamburg, Germany, in July 2008.

  6. String Theory Methods for Condensed Matter Physics

    Science.gov (United States)

    Nastase, Horatiu

    2017-09-01

    Preface; Acknowledgments; Introduction; Part I. Condensed Matter Models and Problems: 1. Lightning review of statistical mechanics, thermodynamics, phases and phase transitions; 2. Magnetism in solids; 3. Electrons in solids: Fermi gas vs. Fermi liquid; 4. Bosonic quasi-particles: phonons and plasmons; 5. Spin-charge separation in 1+1 dimensional solids: spinons and holons; 6. The Ising model and the Heisenberg spin chain; 7. Spin chains and integrable systems; 8. The thermodynamic Bethe ansatz; 9. Conformal field theories and quantum phase transitions; 10. Classical vs. quantum Hall effect; 11. Superconductivity: Landau-Ginzburg, London and BCS; 12. Topology and statistics: Berry and Chern-Simons, anyons and nonabelions; 13. Insulators; 14. The Kondo effect and the Kondo problem; 15. Hydrodynamics and transport properties: from Boltzmann to Navier-Stokes; Part II. Elements of General Relativity and String Theory: 16. The Einstein equation and the Schwarzschild solution; 17. The Reissner-Nordstrom and Kerr-Newman solutions and thermodynamic properties of black holes; 18. Extra dimensions and Kaluza-Klein; 19. Electromagnetism and gravity in various dimensions. Consistent truncations; 20. Gravity plus matter: black holes and p-branes in various dimensions; 21. Weak/strong coupling dualities in 1+1, 2+1, 3+1 and d+1 dimensions; 22. The relativistic point particle and the relativistic string; 23. Lightcone strings and quantization; 24. D-branes and gauge fields; 25. Electromagnetic fields on D-branes. Supersymmetry and N = 4 SYM. T-duality of closed strings; 26. Dualities and M theory; 27. The AdS/CFT correspondence: definition and motivation; Part III. Applying String Theory to Condensed Matter Problems: 28. The pp wave correspondence: string Hamiltonian from N = 4 SYM; 29. Spin chains from N = 4 SYM; 30. The Bethe ansatz: Bethe strings from classical strings in AdS; 31. Integrability and AdS/CFT; 32. AdS/CFT phenomenology: Lifshitz, Galilean and Schrodinger

  7. Surface resistance of superconductors - examples from Nb - O systems

    International Nuclear Information System (INIS)

    Palmer, F.

    1988-01-01

    The observed surface resistance of most superconductors can be written as the sum of two terms. R/sub obs/ = R/sub BCS/ + R/sub res/. This paper is divided into three sections. The first section describes the BCS theory of surface resistance in terms of a simplified two-fluid model. The second section describes several possible causes of residual resistance including normal conducting materials, tunneling across cracks in the surface, and direct generation of phonons by the RF electric field. The last section describes recent experiments having to do with the effects of oxide layers on surface resistance. Layers grown in pure oxygen at room temperature were found to have little or no effect, but if these layers are heated to temperatures near 300 0 C, they can alter both the BCS resistance and the residual resistance. Heated oxide layers also increased the dependence of the residual resistance on ambient magnetic field. 31 references, 13 figures, 3 tables

  8. Pseudo-Coulomb potential in singlet superconductivity

    International Nuclear Information System (INIS)

    Daemen, L.L.; Overhauser, A.W.

    1988-01-01

    Reduction of the screened Coulomb potential parameter μ to μ/sup */ = μ/[1+μ ln(E/sub F//(h/2π)ω/sub D/)] is related to the pair correlation function at r = 0. This correlation function is calculated for both the simple Cooper-pair problem and standard Bardeen-Cooper-Schrieffer (BCS) theory by use of a two-square-well model (with λ and μ describing the attraction and repulsion). Results are compared with values obtained for a one-square-well model (having the suitable net attraction, e.g., λ-μ/sup */ in the BCS case). For the BCS case, the ''true'' pair correlation at r = 0 is reduced by a factor (μ/sup *//μ) 2 relative to the fictitious (one-square-well) value (even though Δ is the same for both models). The reduction factor is typically ≅(1/25. It follows that any short-range attractive contribution to superconducting pairing will suffer a reduction similar to that for the Coulomb repulsion

  9. Enhanced pairing of quantum critical metals near d=3+1

    Energy Technology Data Exchange (ETDEWEB)

    Fitzpatrick, A. Liam; Kachru, Shamit; Kaplan, Jared; Raghu, S.; Torroba, Gonzalo; Wang, Huajia

    2015-07-20

    We study the dynamics of a quantum critical boson coupled to a Fermi surface in intermediate energy regimes where the Landau damping of the boson can be parametrically controlled, either via large Fermi velocity or by large- N techniques. We develop a systematic approach to the BCS instability of such systems, including careful treatment of the enhanced log 2 and log 3 singularities which appear already at 1-loop. These singularities arise due to the exchange of a critical boson in the Cooper channel and are absent in Fermi liquid theory. We also treat possible instabilities to charge density wave (CDW) formation, and compare the scales Λ BCS and Λ CDW of the onset of the instabilities in different parametric regimes. We address the question of whether the dressing of the fermions into a non-Fermi liquid via interactions with the order parameter field can happen at energies > Λ BCS , Λ CDW .

  10. A possible model of heavy fermion superconductivity

    International Nuclear Information System (INIS)

    Zhang Liyuan.

    1986-08-01

    We have used the periodic Anderson Hamiltonian to study the behaviour of heavy fermion systems. It has been argued that the properly large mixing between f and the conduction electrons, the strong Coulomb correlation between f electrons and the related renormalization effect are the main causes of the large effective mass of the quasiparticle. Further, we have introduced phenomenologically the BCS attractive interaction between the heavy quasiparticles and explained that the value of ΔC/γT c and T c may be quite different from that of the BCS theory as a result of the interaction between two branches of the quasiparticles. (author)

  11. In vitro dissolution of generic immediate-release solid oral dosage forms containing BCS class I drugs: comparative assessment of metronidazole, zidovudine, and amoxicillin versus relevant comparator pharmaceutical products in South Africa and India.

    Science.gov (United States)

    Reddy, Nallagundla H S; Patnala, Srinivas; Löbenberg, Raimar; Kanfer, Isadore

    2014-10-01

    Biowaivers are recommended for immediate-release solid oral dosage forms using dissolution testing as a surrogate for in vivo bioequivalence studies. Several guidance are currently available (the World Health Organization (WHO), the US FDA, and the EMEA) where the conditions are described. In this study, definitions, criteria, and methodologies according to the WHO have been applied. The dissolution performances of immediate-release metronidazole, zidovudine, and amoxicillin products purchased in South African and Indian markets were compared to the relevant comparator pharmaceutical product (CPP)/reference product. The dissolution performances were studied using US Pharmacopeia (USP) apparatus 2 (paddle) set at 75 rpm in each of three dissolution media (pH1.2, 4.5, and 6.8). Concentrations of metronidazole, zidovudine, and amoxicillin in each dissolution media were determined by HPLC. Of the 11 metronidazole products tested, only 8 could be considered as very rapidly dissolving products as defined by the WHO, whereas 2 of those products could be considered as rapidly dissolving products but did not comply with the f 2 acceptance criteria in pH 6.8. All 11 zidovudine products were very rapidly dissolving, whereas in the case of the 14 amoxicillin products tested, none of those products met any of the WHO criteria. This study indicates that not all generic products containing the same biopharmaceutics classification system (BCS) I drug and in similar strength and dosage form are necessarily in vitro equivalent. Hence, there is a need for ongoing market surveillance to determine whether marketed generic products containing BCS I drugs meet the release requirements to confirm their in vitro bioequivalence to the respective reference product.

  12. Resonance superfluidity in a quantum degenerate Fermi gas

    NARCIS (Netherlands)

    Kokkelmans, S.J.J.M.F.; Holland, M.; Walser, R.; Chiofalo, M.L.; Chu, S.; Vuletic, V.; Kerman, A.J.; Chin, C.

    2002-01-01

    We consider the superfluid phase transition that arises when a Feshbach resonance pairing occurs in a dilute Fermi gas. This is related to the phenomenon of superconductivity described by the seminal Bardeen-Cooper-Schrieffer (BCS) theory. In superconductivity, the phase transition is caused by a

  13. Thermodynamics of pairing phase transition in nuclei

    International Nuclear Information System (INIS)

    Karim, Afaque; Ahmad, Shakeb

    2014-01-01

    The pairing gaps, pairing energy, heat capacity and entropy are calculated within BCS (Bardeen- Cooper-Schrieffer) based quasi particle approach, including thermal fluctuations on pairing field within pairing model for all nuclei (light, medium, heavy and super heavy nuclei). Quasi particles approach in BCS theory was introduced and reformulated to study various properties. For thermodynamic behavior of nuclei at finite temperatures, the anomalous averages of creation and annihilation operators are introduced. It is solved self consistently at finite temperatures to obtain BCS Hamiltonian. After doing unitary transformation, we obtained the Hamiltonian in the diagonal form. Thus, one gets temperature dependence gap parameter and pairing energy for nuclei. Moreover, the energy at finite temperatures is the sum of the condensation energy and the thermal energy of fermionic quasi particles. With the help of BCS Hamiltonian, specific heat, entropy and free energy are calculated for different nuclei. In this paper the gap parameter occupation number and pairing energy as a function of temperature which is important for all the light, medium, heavy and super heavy nuclei is calculated. Moreover, the various thermo dynamical quantities like specific heat, entropy and free energy is also obtained for different nuclei. Thus, the thermodynamics of pairing phase transition in nuclei is studied

  14. Optimized conditions for MDCK permeability and turbidimetric solubility studies using compounds representative of BCS classes I-IV.

    Science.gov (United States)

    Taub, Mitchell E; Kristensen, Lisbeth; Frokjaer, Sven

    2002-05-01

    The solubility enhancing effects of various excipients, including their compatibility with in vitro permeability (P(app)) systems, was investigated using drugs representative of Biopharmaceutics Classification System (BCS) classes I-IV. Turbidimetric solubility determination using nephelometry and transport experiments using MDCK Strain I cell monolayers were employed. The highest usable concentration of each excipient [dimethyl sulfoxide (DMSO), ethanol, hydroxypropyl-beta-cyclodextrin (HPCD), and sodium taurocholate] was determined by monitoring apical (AP) to basolateral (BL) [14C]mannitol apparent permeability (P(app)) and the transepithelial electrical resistance (TEER) in transport experiments done at pH 6.0 and 7.4. The excipients were used in conjunction with compounds demonstrating relatively low aqueous solubility (amphotericin B, danazol, mefenamic acid, and phenytoin) in order to obtain a drug concentration >50 microM in the donor compartment. The addition of at least one of the selected excipients enhanced the solubility of the inherently poorly soluble compounds to >50 microM as determined via turbidimetric evaluation at pH 6.0 and 7.4. Ethanol and DMSO were found to be generally disruptive to the MDCK monolayer and were not nearly as useful as HPCD and sodium taurocholate. Sodium taurocholate (5 mM) was compatible with MDCK monolayers under all conditions investigated. Additionally, a novel in vitro system aimed at more accurately simulating in vivo conditions, i.e., a pH gradient (6.0 AP/7.4 BL), sodium taurocholate (5 mM, AP), and bovine serum albumin (0.25%, BL), was shown to generate more reliable P(app) values for compounds that are poorly soluble and/or highly protein bound.

  15. A Robust Wide-Area Measurement System for Southern Region of Indian power Grid Using Binary Cuckoo Search (BCS: A Case Study

    Directory of Open Access Journals (Sweden)

    N V Phanendra babu

    2016-03-01

    Full Text Available The current state estimators need to estimate the power system by means of the state variables i.e. voltage and current phasors accurately. Phasor measurement unit (PMU is becoming a most prominent tool for monitoring, control and protection of electric networks, and hence it is required to employ them for the present and future power system networks. An optimal PMU placement (OPP is quite important during planning studies for both existing and future power networks. So, when a new state estimator commissioned, or an existing estimator is up-graded, the problems of minimizing the number of PMUs and their optimal location for system complete observability will come into picture. The approach, in this paper, a Binary Cuckoo Search(BCS method for system complete Observability based optimal PMU placement problem subjected to all possible contingencies and PMU communication channel limitations is suggested. The suggested method is tested with some of standard IEEE test systems and have been practiced for different State Level Regional power Grids (SLRGs of the Indian power system. The results from the suggested method are also compared with the methods that have been already applied for standard IEEE test systems and SLRGs, and were proved to be best and effective.

  16. Superconducting characteristics of 4-Å carbon nanotube-zeolite composite

    KAUST Repository

    Lortz, Rolf W.; Zhang, Qiucen; Shi, Wu; Ye, JiangTing; Qiu, Chunyin; Wang, Zhe; He, Hongtao; Sheng, Ping; Qian, Tiezheng; Tang, Zikang; Wang, Ning; Zhang, Xixiang; Wang, Jiannong; Chan, Cheting

    2009-01-01

    -size effects. Comparison with theory shows the behavior to be consistent with that of a type II BCS superconductor, characterized by a coherence length of 14 ± 2 nm and a magnetic penetration length of 1.5 ± 0.7 μm. Four probe and differential resistance

  17. Factors of influence on acute skin toxicity of breast cancer patients treated with standard three-dimensional conformal radiotherapy (3D-CRT) after breast conserving surgery (BCS)

    International Nuclear Information System (INIS)

    Kraus-Tiefenbacher, Uta; Sfintizky, Andreas; Welzel, Grit; Simeonova, Anna; Sperk, Elena; Siebenlist, Kerstin; Mai, Sabine; Wenz, Frederik

    2012-01-01

    Standard 3D-CRT after BCS may cause skin toxicity with a wide range of intensity including acute effects like erythema or late effects. In order to reduce these side effects it is mandatory to identify potential factors of influence in breast cancer patients undergoing standard three-dimensional conformal radiation therapy (3D-CRT) of the breast and modern systemic therapy. Between 2006 and 2010 a total of 211 breast cancer patients (median age 52,4 years, range 24–77) after BCS consecutively treated in our institution with 3D-CRT (50 Gy whole breast photon radiotherapy followed by 16 Gy electron boost to the tumorbed) were evaluated with special focus on documented skin toxicity at the end of the 50 Gy-course. Standardized photodocumentation of the treated breast was done in each patient lying on the linac table with arms elevated. Skin toxicity was documented according to the common toxicity criteria (CTC)-score. Potential influencing factors were classified in three groups: patient-specific (smoking, age, breast size, body mass index = BMI, allergies), tumor-specific (tumorsize) and treatment-specific factors (antihormonal therapy with tamoxifen or aromatase inhibitors, chemotherapy). Uni- and multivariate statistical analyses were done using IBM SPSS version 19. After 50 Gy 3D-CRT to the whole breast 28.9% of all 211 patients had no erythema, 62.2% showed erythema grade 1 (G1) and 8.5% erythema grade 2. None of the patients had grade 3/4 (G3/4) erythema. In univariate analyses a significant influence or trend on the development of acute skin toxicities (erythema G0 versus G1 versus G2) was observed for larger breast volumes (p=0,004), smoking during radiation therapy (p=0,064) and absence of allergies (p=0,014) as well as larger tumorsize (p=0,009) and antihormonal therapy (p=0.005). Neither patient age, BMI nor choice of chemotherapy showed any significant effect on higher grade toxicity. In the multivariate analysis, factors associated with higher grade

  18. Diffusion of breast conserving surgery in medical communities.

    Science.gov (United States)

    Jerome-D'Emilia, Bonnie; Begun, James W

    2005-01-01

    Excluding skin cancers, breast cancer is the most common form of cancer in women. Due to an increased focus on early detection, many more cases of breast cancer are now diagnosed at an early stage, which makes the use of breast conserving surgery (BCS) an efficacious and often more desirable treatment choice than mastectomy. An analysis of the variation in the use of BCS in the United States was performed using data from the years 1988 and 1994, and stratifying hospitals on the basis of teaching status. In both 1988 and 1994, BCS was highest in academic teaching hospitals and lowest in community hospitals. This finding is interpreted within the framework of classical diffusion theory. Social and cultural norms in local medical communities have a strong effect on the degree to which innovations diffuse rapidly or not. This analysis is useful in the understanding of geographic and hospital-based variations in treatment for early stage breast cancer and other illnesses that have long and strongly held traditions of treatment.

  19. Superconductivity a new approach based on the Bethe-Salpeter equation in the mean-field approximation

    CERN Document Server

    Malik, G P

    2016-01-01

    Given the Debye temperature of an elemental superconductor (SC) and its Tc, BCS theory enables one to predict the value of its gap 0 at T = 0, or vice versa. This monograph shows that non-elemental SCs can be similarly dealt with via the generalized BCS equations (GBCSEs) which, given any two parameters of the set {Tc, 10, 20 > 10}, enable one to predict the third. Also given herein are new equations for the critical magnetic field and critical current density of an elemental and a non-elemental SC — equations that are derived directly from those that govern pairing in them. The monograph includes topics that are usually not covered in any one text on superconductivity, e.g., BCS-BEC crossover physics, the long-standing puzzle posed by SrTiO3, and heavy-fermion superconductors — all of which are still imperfectly understood and therefore continue to avidly engage theoreticians. It suggests that addressing the Tcs, s and other properties (e.g., number densities of charge carriers) of high-Tc SCs via GBCSE...

  20. New methods in nuclear reaction theory

    International Nuclear Information System (INIS)

    Redish, E.F.

    1979-01-01

    Standard nuclear reaction methods are limited to treating problems that generalize two-body scattering. These are problems with only one continuous (vector) degree of freedom (CDOF). The difficulty in extending these methods to cases with two or more CDOFs is not just the additional numerical complexity: the mathematical problem is usually not well-posed. It is hard to guarantee that the proper boundary conditions (BCs) are satisfied. Since this is not generally known, the discussion is begun by considering the physics of this problem in the context of coupled-channel calculations. In practice, the difficulties are usually swept under the rug by the use of a highly developed phenomenology (or worse, by the failure to test a calculation for convergence). This approach limits the kind of reactions that can be handled to ones occurring on the surface of where a second CDOF can be treated perturbatively. In the past twenty years, the work of Faddeev, the quantum three-body problem has been solved. Many techniques (and codes) are now available for solving problems with two CDOFs. A method for using these techniques in the nuclear N-body problem is presented. A set of well-posed (connected kernal) equations for physical scattering operators is taken. Then it is shown how approximation schemes can be developed for a wide range of reaction mechanisms. The resulting general framework for a reaction theory can be applied to a number of nuclear problems. One result is a rigorous treatment of multistep transfer reactions with the possibility of systematically generating corrections. The application of the method to resonance reactions and knock-out is discussed. 12 figures

  1. Comparison of the permeability of metoprolol and labetalol in rat, mouse, and Caco-2 cells: use as a reference standard for BCS classification.

    Science.gov (United States)

    Incecayir, Tuba; Tsume, Yasuhiro; Amidon, Gordon L

    2013-03-04

    The purpose of this study was to investigate labetalol as a potential high permeability reference standard for the application of Biopharmaceutics Classification Systems (BCS). Permeabilities of labetalol and metoprolol were investigated in animal intestinal perfusion models and Caco-2 cell monolayers. After isolating specific intestinal segments, in situ single-pass intestinal perfusions (SPIP) were performed in rats and mice. The effective permeabilities (Peff) of labetalol and metoprolol, an FDA standard for the low/high Peff class boundary, were investigated in two different segments of rat intestine (proximal jejunum and distal ileum) and in the proximal jejunum of mouse. No significant difference was found between Peff of metoprolol and labetalol in the jejunum and ileum of rat (0.33 ± 0.11 × 10(-4) vs 0.38 ± 0.06 × 10(-4) and 0.57 ± 0.17 × 10(-4) vs 0.64 ± 0.30 × 10(-4) cm/s, respectively) and in the jejunum of mouse (0.55 ± 0.05 × 10(-4) vs 0.59 ± 0.13 × 10(-4) cm/s). However, Peff of metoprolol and labetalol were 1.7 and 1.6 times higher in the jejunum of mouse, compared to the jejunum of rat, respectively. Metoprolol and labetalol showed segmental-dependent permeability through the rat intestine, with increased Peff in the distal ileum in comparison to the proximal jejunum. Most significantly, Peff of labetalol was found to be concentration-dependent. Decreasing concentrations of labetalol in the perfusate resulted in decreased Peff compared to Peff of metoprolol. The intestinal epithelial permeability of labetalol was lower than that of metoprolol in Caco-2 cells at both apical pH 6.5 and 7.5 (5.96 ± 1.96 × 10(-6) vs 9.44 ± 3.44 × 10(-6) and 15.9 ± 2.2 × 10(-6) vs 23.2 ± 7.1 × 10(-6) cm/s, respectively). Labetalol exhibited higher permeability in basolateral to apical (BL-AP) compared to AP-BL direction in Caco-2 cells at 0.1 times the highest dose strength (HDS) (46.7 ± 6.5 × 10(-6) vs 14.2 ± 1.5 × 10(-6) cm/s). The P

  2. Far-infrared transmission of a superconducting NbN film

    Czech Academy of Sciences Publication Activity Database

    Šindler, M.; Tesař, Roman; Koláček, Jan; Skrbek, L.; Šimša, Zdeněk

    2010-01-01

    Roč. 81, č. 18 (2010), 184529/1-184529/5 ISSN 1098-0121 R&D Projects: GA ČR GA202/08/0326 Institutional research plan: CEZ:AV0Z10100521 Keywords : superconductivity * BCS theory * terahertz radiation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.772, year: 2010

  3. Shape evolution of 72,74Kr with temperature in covariant density functional theory

    Institute of Scientific and Technical Information of China (English)

    Wei Zhang; Yi-Fei Niu

    2017-01-01

    The rich phenomena of deformations in neutron-deficient krypton isotopes,such as shape evolution with neutron number and shape coexistence,have attracted the interest of nuclear physicists for decades.It is interesting to study such shape phenomena using a novel way,e.g.by thermally exciting the nucleus.In this work,we develop the finite temperature covariant density functional theory for axially deformed nuclei with the treatment of pairing correlations by the BCS approach,and apply this approach for the study of shape evolution in 72,74Kr with increasing temperature.For 72Kr,with temperature increasing,the nucleus firstly experiences a relatively quick weakening in oblate deformation at temperature T~0.9 MeV,and then changes from oblate to spherical at T~2.1 MeV.For 74Kr,its global minimum is at quadrupole deformationβ2 ~-0.14 and abruptly changes to spherical at T~ 1.7 MeV.The proton pairing transition occurs at critical temperature 0.6 MeV following the rule Tc=0.6Ap(0),where △p(0) is the proton pairing gap at zero temperature.The signatures of the above pairing transition and shape changes can be found in the specific heat curve.The single-particle level evolutions with temperature are presented.

  4. Seismic monitoring during acid stimulation of wells LV-4 and LV-13 at the Las Tres Virgenes geothermal field, BCS, Mexico; Monitoreo sismico durante la estimulacion acida de los pozos LV-4 y LV-13 del campo geotermico de Las Tres Virgenes, BCS, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Venegas Salgado, Saul; Arredondo Fragoso, Jesus; Ramirez Silva, German; Flores Armenta, Magaly; Ramirez Montes, Miguel [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Morelia, Michoacan (Mexico)]. E-mail: magaly.flores@cfe.gob.mx

    2006-07-15

    From September through December 2004 a seismic monitoring in the Las Tres Virgenes, BCS, geothermal field was carried out simultaneously with the acid stimulation of wells LV-4 and LV-13. The seismic network had four digital seismographs and recorded 174 local seismic events, 131 regional ones and many more volcanic signals at seismic station TV20 during the acid stimulation. Additionally, 37 seismic events were located, 22 of them inside the most important geothermal zone at depths between 0.4 and 4 km with typically low magnitudes (0.7 to 2.2 Md). Two relevant zones were determined: Zone A related to the El Volcan fault system and Zone B related to injection well LV-8. In Zone A the well-induction stage and the operation start of the wells LV-4 and LV-13 after acidification on October 30 and November 17, 2004, increased seismic activity to a maximum of 12 daily events in early December. When the two wells in Zone B were cooled before the acidification, the seismic events recorded there increased to a maximum of 6 daily events on October 2, and then decreased. Also in Zone B the seismic activity increased after well-induction and the start of well production once they were acidified, recording up to 11 daily events in late November. According to the seismic distribution, we may conclude that the most active fault systems are El Volcan and El Viejo. New proposals for well locations in the field are supported by these results. [Spanish] De septiembre a diciembre de 2004 se realizo un estudio de monitoreo sismico en el campo geotermico de Las Tres Virgenes, BCS, simultaneamente con las estimulaciones acidas de los pozos LV-4 y LV-13. Se utilizo una red sismica conformada por cuatro sismografos digitales, logrando registrar en la estacion sismica TV20 un total de 174 sismos locales, 131 sismos regionales y muchas mas senales de tipo volcanico, durante el periodo del monitoreo de la estimulacion acida. Ademas, se localizaron un total de 37 sismos, de los cuales 22 se

  5. Superconductivity revisited

    CERN Document Server

    Dougherty, Ralph

    2013-01-01

    While the macroscopic phenomenon of superconductivity is well known and in practical use worldwide in many industries, including MRIs in medical diagnostics, the current theoretical paradigm for superconductivity (BCS theory) suffers from a number of limitations, not the least of which is an adequate explanation of high temperature superconductivity. This book reviews the current theory and its limitations and suggests new ideas and approaches in addressing these issues. The central objective of the book is to develop a new, coherent, understandable theory of superconductivity directly based on molecular quantum mechanics.

  6. POCT PT INR - Is it adequate for patient care? A comparison of the Roche Coaguchek XS vs. Stago Star vs. Siemens BCS in patients routinely seen in an anticoagulation clinic.

    Science.gov (United States)

    Baker, Wendy S; Albright, Kathleen J; Berman, Megan; Spratt, Heidi; Mann, Peggy A; Unabia, Jaime; Petersen, John R

    2017-09-01

    In this study we examined the difference in patient INR values as measured by the POCT CoaguChek XS device and central laboratory Stago Evolution and Siemens BCS XP analyzers. This study composed of 100 warfarin therapy patients and 20 coagulation normal subjects, showed that the difference between the POCT and clinical laboratory values increased with increasing INR and was exacerbated by the use of different thromboplastin reagents by the POCT and central lab. The CoaguChek XS and on-site Stago analyzers which used human recombinant (ISI=1.01) and rabbit brain thromboplastin (ISI=1.25), respectively, showed reasonable agreement for INR5.0 with the Stago Evolution prevented adverse treatment events for the warfarin therapy patients in the six months preceding and following this investigation. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Scanning tunneling spectroscopic studies of superconducting NbN single crystal thin films at 4.2 K

    International Nuclear Information System (INIS)

    Kashiwaya, S.; Koyanagi, M.; Matsuda, M.; Shoji, A.; Shibata, H.

    1991-01-01

    This paper reports on a Low Temperature Scanning Tunneling Microscope (LTSTM) constructed to study the microscopic properties of superconductors. It has atomic resolution from room temperature to 4.2 K. Conductance spectra obtained between a Pt tip and a NbN thin film agreed well with theoretical curves based on the BCS theory

  8. Superconducting and other phases in organic high polymers of polyacenic carbon skeletons. II. The mean field method

    International Nuclear Information System (INIS)

    Kimura, M.; Kawabe, H.; Nishikawa, K.; Aono, S.

    1986-01-01

    Ordered phases such as CDW, SDW, and the singlet superconductivity(SSC) are predicted by means of a mean field theory. The electronic Hamiltonian is linearized by introducing order parameters which are expected to arise, and these order parameters are determined self-consistently. The behaviors of gap, transition temperature, and condensation energy are greatly different from those of BCS theory. The coexistence of the various phases is discussed. Aside from a very special case the single phase is most stable

  9. Quark ensembles with the infinite correlation length

    Science.gov (United States)

    Zinov'ev, G. M.; Molodtsov, S. V.

    2015-01-01

    A number of exactly integrable (quark) models of quantum field theory with the infinite correlation length have been considered. It has been shown that the standard vacuum quark ensemble—Dirac sea (in the case of the space-time dimension higher than three)—is unstable because of the strong degeneracy of a state, which is due to the character of the energy distribution. When the momentum cutoff parameter tends to infinity, the distribution becomes infinitely narrow, leading to large (unlimited) fluctuations. Various vacuum ensembles—Dirac sea, neutral ensemble, color superconductor, and BCS state—have been compared. In the case of the color interaction between quarks, the BCS state has been certainly chosen as the ground state of the quark ensemble.

  10. Quark ensembles with the infinite correlation length

    International Nuclear Information System (INIS)

    Zinov’ev, G. M.; Molodtsov, S. V.

    2015-01-01

    A number of exactly integrable (quark) models of quantum field theory with the infinite correlation length have been considered. It has been shown that the standard vacuum quark ensemble—Dirac sea (in the case of the space-time dimension higher than three)—is unstable because of the strong degeneracy of a state, which is due to the character of the energy distribution. When the momentum cutoff parameter tends to infinity, the distribution becomes infinitely narrow, leading to large (unlimited) fluctuations. Various vacuum ensembles—Dirac sea, neutral ensemble, color superconductor, and BCS state—have been compared. In the case of the color interaction between quarks, the BCS state has been certainly chosen as the ground state of the quark ensemble

  11. Quark ensembles with the infinite correlation length

    Energy Technology Data Exchange (ETDEWEB)

    Zinov’ev, G. M. [National Academy of Sciences of Ukraine, Bogoliubov Institute for Theoretical Physics (Ukraine); Molodtsov, S. V., E-mail: molodtsov@itep.ru [Joint Institute for Nuclear Research (Russian Federation)

    2015-01-15

    A number of exactly integrable (quark) models of quantum field theory with the infinite correlation length have been considered. It has been shown that the standard vacuum quark ensemble—Dirac sea (in the case of the space-time dimension higher than three)—is unstable because of the strong degeneracy of a state, which is due to the character of the energy distribution. When the momentum cutoff parameter tends to infinity, the distribution becomes infinitely narrow, leading to large (unlimited) fluctuations. Various vacuum ensembles—Dirac sea, neutral ensemble, color superconductor, and BCS state—have been compared. In the case of the color interaction between quarks, the BCS state has been certainly chosen as the ground state of the quark ensemble.

  12. Q factor and resonance amplitude of Josephson tunnel junctions

    International Nuclear Information System (INIS)

    Broom, R.F.; Wolf, P.

    1977-01-01

    The surface impedance of the superconducting films comprising the electrodes of Josephson tunnel junctions has been derived from the BCS theory in the extreme London limit. Expressions have been obtained for (i) the dependence of the penetration depth lambda on frequency and temperature, and (ii) the quality factor Q of the junction cavity, attributable to surface absorption in the electrodes. The effect of thin electrodes (t 9 or approx. = lambda) is also included in the calculations. Comparison of the calculated frequency dependence of lambda with resonance measurements on Pb-alloy and all-Nb tunnel junctions yields quite good agreement, indicating that the assumptions made in the theory are reasonable. Measurements of the (current) amplitude of the resonance peaks of the junctions have been compared with the values obtained from inclusion of the calculated Q in the theory by Kulik. In common with observations on microwave cavities by other workers, we find that a small residual conductivity must be added to the real part of the BCS value. With its inclusion, good agreement is found between calculation and experiment, within the range determined by the simplifying assumptions of Kulik's theory. From the results, we believe the calculation of Q to be reasonably accurate for the materials investigated. It is shown that the resonance amplitude of Josephson junctions can be calculated directly from the material constants and a knowledge of the residual conductivity

  13. Effects of Interfacial Translation-rotation Coupling for Confined Ferrofluids

    Science.gov (United States)

    Fang, Angbo

    2011-03-01

    Ferrofluids have wide applications ranging from semiconductor fabrications to biomedical processes. The hydrodynamic spin diffusion theory for ferrofluids has been successful in explaining many experimental data, but it suffers from some fatal flaws. For example, it fails to predict the incorrect flow direction for a ferrofluid confined in a concentric cylinder channel in the presence of a rotating magnetic field. In this work we develop a method to establish the general hydrodynamic boundary conditions (BCs) for micro-polar fluids such as ferrofluids. Through a dynamic generalization of the mesoscopic diffuse interface model, we are able to obtain the surface dissipation functional, in which the interfacial translation-rotation coupling plays a significant role. The generalized hydrodynamic BCs can be obtained straightforwardly by using Onsager's variational approach. The resulted velocity profile and other quantities compares well with the experimental data, strikingly different from traditional theories. The methodology can be applied to study the hydrodynamic behavior of other structured fluids in confined channels or multi-phase flows. The work is supported by a research award made by the King Abdullah University of Science and Technology.

  14. Contribution to the theory of ultracold highly polarized Fermi gases

    International Nuclear Information System (INIS)

    Giraud, Sebastien

    2010-01-01

    This thesis deals with the N+1 body problem in highly polarized Fermi gases. This is the situation where a single atom of one spin species is immersed in a Fermi sea of atoms of the other species. The first part uses a Hamiltonian approach based on a general expansion for the wave function of the system with any number of particle-hole pairs. We show that the constructed series of successive approximations converges very rapidly and thus we get an essentially exact solution for the energy and the effective mass of the polaron. In one dimension, for two particular cases, this problem can be solved analytically. The excellent agreement with our series of approximations provides a further check of the reliability of this expansion. Finally, we consider more specifically various limiting cases, as well as the effect of the mass ratio between the two spin species. In the second part, we use the Feynman diagrams formalism to describe both the polaron and the bound state. For the polaron, we develop a theory which is equivalent to the Hamiltonian approach. For the bound state, we get again a series of successive approximations whose fast convergence is perfectly understood. Therefore, this approach provides an essentially exact solution to the problem along the whole BEC-BCS crossover. Finally, by comparing the energies of the two quasi-particles, we study the position of the polaron to bound state transition. (author)

  15. Improved perception of communication and compliance with a revised, intensive care unit-specific bedside communication sheet.

    Science.gov (United States)

    Aponte-Patel, Linda; Sen, Anita

    2015-01-01

    Although many pediatric intensive care units (PICUs) use beside communication sheets (BCSs) to highlight daily goals, the optimal format is unknown. A site-specific BCS could improve both PICU communication and compliance completing the BCS. Via written survey, PICU staff at an academic children's hospital provided recommendations for improving and revising an existing BCS. Pre- and post-BCS revision, PICU staff were polled regarding PICU communication and BCS effectiveness, and daily compliance for completing the BCS was monitored. After implementation of the revised BCS, staff reporting "excellent" or "very good" day-to-day communication within the PICU increased from 57% to 77% (P = .02). Compliance for completing the BCS also increased significantly (75% vs 83%, P = .03). Introduction of a focused and concise BCS tailored to a specific PICU leads to improved perceptions of communication by PICU staff and increased compliance completing the daily BCS. © The Author(s) 2014.

  16. Superconducting fluctuations in systems with Rashba-spin-orbit coupling

    Energy Technology Data Exchange (ETDEWEB)

    Beyl, Stefan [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg (Germany); Orth, Peter P.; Scheurer, Mathias; Schmalian, Joerg [Institut fuer Theorie der Kondensierten Materie, Karlsruher Institut fuer Technologie (Germany)

    2015-07-01

    We investigate the BEC-BCS crossover in a two-dimensional system with Rashba-spin-orbit coupling. To include the effects of phase and amplitude fluctuations of the superconducting order parameter we perform a loop expansion of the effective field theory. We analyze in particular the probability of a low density superconducting quantum phase transition. The theory is relevant to LaAlO{sub 3}/SrTiO{sub 3} interfaces and two-dimensional cold atom systems with synthetic gauge fields.

  17. New superconductor LaRhSb

    International Nuclear Information System (INIS)

    Nishigori, S.; Moriwaki, H.; Suzuki, T.; Fujita, T.; Tanaka, H.; Takabatake, T.; Fujii, H.

    1994-01-01

    Superconductivity in LaRhSb was newly found below the transition temperature T c = 2.67 K by the measurements of the electrical resistivity, magnetic susceptibility and specific heat in magnetic fields. The characteristics of the superconductivity determined in this study indicate that LaRhSb is a type II superconductor following the BCS theory. (orig.)

  18. Supercondutors

    International Nuclear Information System (INIS)

    Frota-Pessoa, S.

    1987-01-01

    The evolution of superconductors, since its discovery until the approach of ceramic superconductors is presented. A brief introduction of BCS theory is done, and some interesting properties under tecnological point of view are discussed. The ceramic superconductors, its tecnological powerful and the raised points with the approach of these new materials are emphasized. (M.C.K.) [pt

  19. Charged vortices in high-Tc superconductors

    International Nuclear Information System (INIS)

    Matsuda, Y.; Kumagai, K.

    2002-01-01

    It is well known that a vortex in type II superconductors traps a magnetic flux. Recently the possibility that a vortex can accumulate a finite electric charge as well has come to be realized. The sign and magnitude of the vortex charge not only is closely related to the microscopic electronic structure of the vortex, but also strongly affects the dynamical properties of the vortex. In this chapter we demonstrate that a vortex in high-T c superconductors (HTSC) indeed traps a finite electronic charge, using the high resolution measurements of the nuclear quadrupole frequencies. We then discuss the vortex Hall anomaly whose relation with the vortex charging effect has recently received considerable attention. We show that the sign of the trapped charge is opposite to the sign predicted by the conventional BCS theory and deviation of the magnitude of the charge from the theory is also significant. We also show that the electronic structure of underlying system is responsible for the Hall sign in the vortex state and again the Hall sign is opposite to the sign predicted by the BCS theory. It appears that these unexpected features observed in both electrostatics and dynamics of the vortex may be attributed to the novel electronic structure of the vortex in HTSC. (orig.)

  20. Tunneling dynamics of superfluid Fermi gases in an accelerating optical lattice

    International Nuclear Information System (INIS)

    Tie Lu; Xue Jukui

    2010-01-01

    The nonlinear Landau-Zener tunneling and the nonlinear Rabi oscillations of superfluid Fermi gases between Bloch bands in an accelerating optical lattice are discussed. Within the hydrodynamic theory and a two-level model, the tunneling probability of superfluid Fermi gases between Bloch bands is obtained. We find that, as the system crosses from the Bose-Einstein condensation (BEC) side to the BCS side, the tunneling rate is closely related to the particle density: when the density is smaller (larger) than a critical value, the tunneling rate at unitarity is larger (smaller) than that in the BEC limit. This is well explained in terms of an effective interaction and an effective potential. Furthermore, the nonlinear Rabi oscillations of superfluid Fermi gases between the bands are discussed by imposing a periodic modulation on the level bias and the strength of the lattice. Analytical expressions of the critical density for suppressing or enhancing the Rabi oscillations are obtained. It is shown that, as the system crosses from the BEC side to the BCS side, the critical density strongly depends on the modulation parameters (i.e., the modulation amplitude and the modulation frequency). For a fixed density, a high-frequency or low-frequency modulation can suppress or enhance the Rabi oscillations both at unitarity and in the BEC limit. For an intermediate modulation frequency, the Rabi oscillations are chaotic along the entire BEC-BCS crossover, especially, on the BCS side. Interestingly, we find that the modulation of the lattice strength only with an intermediate modulation frequency has significant effect on the Rabi oscillations both in the BEC limit and at unitarity; that is, an intermediate-frequency modulation can enhance the Rabi oscillations, especially on the BCS side.

  1. Stability of Sarma phases in density imbalanced electron-hole bilayer systems

    International Nuclear Information System (INIS)

    Subasi, A. L.; Tanatar, B.; Pieri, P.; Senatore, G.

    2010-01-01

    We study excitonic condensation in an electron-hole bilayer system with unequal layer densities at zero temperature. Using mean-field theory we solve the Bardeen-Cooper-Schrieffer (BCS) gap equations numerically and investigate the effects of intralayer interactions. The electron-hole system evolves from BCS in the weak coupling limit to Bose-Einstein condensation (BEC) in the strong coupling limit. We analyze the stability of the Sarma phase with k,-k pairing by calculating the superfluid mass density and also by checking the compressibility matrix. We find that with bare Coulomb interactions the superfluid density is always positive in the Sarma phase, due to a peculiar momentum structure of the gap function originating from the singular behavior of the Coulomb potential at zero momentum and the presence of a sharp Fermi surface. Introducing a simple model for screening, we find that the superfluid density becomes negative in some regions of the phase diagram, corresponding to an instability toward a Fulde-Ferrel-Larkin-Ovchinnikov-type superfluid phase. Thus, intralayer interaction and screening together can lead to a rich phase diagram in the BCS-BEC crossover regime in electron-hole bilayer systems.

  2. [Biopharmaceutics classification and absorption mechanisms primary study on four kinds of flavonoids].

    Science.gov (United States)

    Li, Hui-Fang; Zhang, Dong; Qu, Wen-Jun; Wang, Hai-Lin; Liu, Yang; Borjigdai, Almaz; Cui, Jian; Dong, Zheng-Qi

    2016-04-01

    The solubility and permeability on four kinds of flavonoids (kaempferol, hesperidin, apigenin, genistein) were test according to the theory of biopharmaceutics classification system (BCS), and their absorption mechanism. The solubility was investigated by the method in determination of solubility of "Chinese Pharmacopoeia 2010". To detect appearance permeability of compounds mentioned above, the appropriate concentrations were selected by the MTT method in cell transfer experiments in Caco-2 cell model, which established by in vitro cell culture method. Therefore, these compounds were classified with BCS according to solubility and permeability. In addition, to explore absorption mechanisms, the experiments in three different concentrations of compounds in high, medium and low in bidirectional transformation methods in Caco-2 cell model contacted. The study indicated that all of kaempferol, hesperidin, apigenin, genistein have the characteristics in low solubility and high permeability, which belong to BCSⅡ, and the absorption mechanism of kaempferol was active transportation. Whereas, hesperidin, apigenin, genistein were passive transportation. In this study, it carried out initial explorations on establishment of determination for solubility and permeability in flavonoids, and provided theoretical reference for further research on BCS in traditional Chinese medicine. Copyright© by the Chinese Pharmaceutical Association.

  3. Isominkowskian theory of Cooper Pairs in superconductors

    International Nuclear Information System (INIS)

    Animalu, A.O.E.

    1993-01-01

    Via the use of Santilli's isominkowskian space, the author presents a relativistic extension of the author's recent treatment of the Cooper Pair in superconductivity based on the Lie-isotopic lifting of quantum mechanics known as Hadronic Mechanics. The isominkowskian treatment reduces the solution of the eiganvalue problem for the quasiparticle energy spectrum to a geometric problem of specifying the metric of the isominkowskian space inside the pair in various models of ordinary high T c superconductors. The use of an intriguing realization of the metric due to Dirac reduces the dimensionality of the interior space to two yielding a spin mutation from 1/2 to zero inside a Cooper pair in two-band BCS and Hubbard models. 12 refs

  4. Goldstone and Higgs Hydrodynamics in the BCS–BEC Crossover

    Directory of Open Access Journals (Sweden)

    Luca Salasnich

    2017-06-01

    Full Text Available We discuss the derivation of a low-energy effective field theory of phase (Goldstone and amplitude (Higgs modes of the pairing field from a microscopic theory of attractive fermions. The coupled equations for Goldstone and Higgs fields are critically analyzed in the Bardeen–Cooper–Schrieffer (BCS-to-Bose–Einstein condensate (BEC crossover—both in three spatial dimensions and in two spatial dimensions. The crucial role of pair fluctuations is investigated, and the beyond-mean-field Gaussian theory of the BCS–BEC crossover is compared with available experimental data of the two-dimensional ultracold Fermi superfluid.

  5. Genetic evaluation for body condition score in Italian Brown Swiss cattle

    Directory of Open Access Journals (Sweden)

    C. Nicoletti

    2010-04-01

    Full Text Available Body Condition Score (BCS evaluates the body energy reserve in a cow using a numeric classification. It is possible to use the BCS as an indirect indicator of fertility. The genetic evaluation for BCS in Italian Brown Swiss is performed on 73125 BCS evaluations on the same number of primiparous, daughters of 507 sires. Effect of herd by year goes from -1,02 to +0,94 indicating large differences among herds. The primiparous cows show about 3.2 BCS points at calving, their BCS decreases slightly during first 90 milking days but, after this period, the BCS increases until 3.5 BCS points at the end of first lactation. Sires with larger EBVs guarantee a slower decrease of BCS during the first part of lactation, which is preferred to the strong decrease exhibited by the daughter of low EBV sires. The pseudo-genetic correlations, correlations values estimated among EBV, confirmed the relationships between BCS and other important traits like milk yield (-0.20, final score, dairyness and udder. The correlations between BCS and functional traits, milking speed and functional longevity, is -0.14 and +0.17 respectively.

  6. Fluctuation instability of the Dirac Sea in quark models of strong interactions

    Science.gov (United States)

    Zinovjev, G. M.; Molodtsov, S. V.

    2016-03-01

    A number of exactly integrable (quark) models of quantum field theory that feature an infinite correlation length are considered. An instability of the standard vacuum quark ensemble, a Dirac sea (in spacetimes of dimension higher than three), is highlighted. It is due to a strong ground-state degeneracy, which, in turn, stems from a special character of the energy distribution. In the case where the momentumcutoff parameter tends to infinity, this distribution becomes infinitely narrow and leads to large (unlimited) fluctuations. A comparison of the results for various vacuum ensembles, including a Dirac sea, a neutral ensemble, a color superconductor, and a Bardeen-Cooper-Schrieffer (BCS) state, was performed. In the presence of color quark interaction, a BCS state is unambiguously chosen as the ground state of the quark ensemble.

  7. Fluctuation instability of the Dirac Sea in quark models of strong interactions

    International Nuclear Information System (INIS)

    Zinovjev, G. M.; Molodtsov, S. V.

    2016-01-01

    A number of exactly integrable (quark) models of quantum field theory that feature an infinite correlation length are considered. An instability of the standard vacuum quark ensemble, a Dirac sea (in spacetimes of dimension higher than three), is highlighted. It is due to a strong ground-state degeneracy, which, in turn, stems from a special character of the energy distribution. In the case where the momentumcutoff parameter tends to infinity, this distribution becomes infinitely narrow and leads to large (unlimited) fluctuations. A comparison of the results for various vacuum ensembles, including a Dirac sea, a neutral ensemble, a color superconductor, and a Bardeen–Cooper–Schrieffer (BCS) state, was performed. In the presence of color quark interaction, a BCS state is unambiguously chosen as the ground state of the quark ensemble.

  8. Fluctuation instability of the Dirac Sea in quark models of strong interactions

    Energy Technology Data Exchange (ETDEWEB)

    Zinovjev, G. M., E-mail: Gennady.Zinovjev@cern.ch [National Academy of Sciences of Ukraine, Bogolyubov Institute for Theoretical Physics (Ukraine); Molodtsov, S. V. [Joint Institute for Nuclear Research (Russian Federation)

    2016-03-15

    A number of exactly integrable (quark) models of quantum field theory that feature an infinite correlation length are considered. An instability of the standard vacuum quark ensemble, a Dirac sea (in spacetimes of dimension higher than three), is highlighted. It is due to a strong ground-state degeneracy, which, in turn, stems from a special character of the energy distribution. In the case where the momentumcutoff parameter tends to infinity, this distribution becomes infinitely narrow and leads to large (unlimited) fluctuations. A comparison of the results for various vacuum ensembles, including a Dirac sea, a neutral ensemble, a color superconductor, and a Bardeen–Cooper–Schrieffer (BCS) state, was performed. In the presence of color quark interaction, a BCS state is unambiguously chosen as the ground state of the quark ensemble.

  9. An introduction to superconductivity. The Meissner effect and the derivation of phenomenological models

    Energy Technology Data Exchange (ETDEWEB)

    Habeney, Lucas

    2016-09-23

    The purpose of this work was to give the reader insight into the topic of conventional superconductors. It started out with defining the superconductive state itself as a state of ideal conductivity and ideal diamagnetism. An important phenomenon to keep in mind in this regard is the Meissner-Ochsenfeld effect. It then went on to attempt to understand those properties on a macroscopic level. This was achieved in the framework of the two major macroscopic theories, the London theory and the Ginzburg-Landau theory. While the London theory focused on the electrodynamic qualities of the superconductive state, the Ginzburg-Landau theory dealt with events close to the superconducting phase transition in a thermodynamic scope. The highlight of this section was the investigation of the Abrikosov lattice, the geometric disposition of the flux tubes in the intermediate Shubnikov phase. We closed with the BCS theory as the premier microscopic theory of superconductivity. Main subjects of this section were the concept of Cooper pairs and the calculation of various energy gap equations. We also looked at real properties of superconductors such as the specific heat to test our rather abstract calculations and came to outstanding agreements. The principles presented in this document should serve as a foundation to work on more advanced problems in superconductivity. Especially the large field of unconventional superconductivity is of huge interest in current research, as most of the high T{sub c} superconductors fall in that category. As unconventional superconductors can not be explained with BCS theory, the search for a uniform theory to describe them is still on-going. Unconventional superconductors include but are not limited to cuprates (T{sub c}

  10. Critical temperature for shape transition in hot nuclei within covariant density functional theory

    Science.gov (United States)

    Zhang, W.; Niu, Y. F.

    2018-05-01

    Prompted by the simple proportional relation between critical temperature for pairing transition and pairing gap at zero temperature, we investigate the relation between critical temperature for shape transition and ground-state deformation by taking even-even Cm-304286 isotopes as examples. The finite-temperature axially deformed covariant density functional theory with BCS pairing correlation is used. Since the Cm isotopes are the newly proposed nuclei with octupole correlations, we studied in detail the free energy surface, the Nilsson single-particle (s.p.) levels, and the components of s.p. levels near the Fermi level in 292Cm. Through this study, the formation of octupole equilibrium is understood by the contribution coming from the octupole driving pairs with Ω [N ,nz,ml] and Ω [N +1 ,nz±3 ,ml] for single-particle levels near the Fermi surfaces as it provides a good manifestation of the octupole correlation. Furthermore, the systematics of deformations, pairing gaps, and the specific heat as functions of temperature for even-even Cm-304286 isotopes are discussed. Similar to the relation between the critical pairing transition temperature and the pairing gap at zero temperature Tc=0.6 Δ (0 ) , a proportional relation between the critical shape transition temperature and the deformation at zero temperature Tc=6.6 β (0 ) is found for both octupole shape transition and quadrupole shape transition for the isotopes considered.

  11. pH-Dependent Solubility and Dissolution Behavior of Carvedilol--Case Example of a Weakly Basic BCS Class II Drug.

    Science.gov (United States)

    Hamed, Rania; Awadallah, Areeg; Sunoqrot, Suhair; Tarawneh, Ola; Nazzal, Sami; AlBaraghthi, Tamadur; Al Sayyad, Jihan; Abbas, Aiman

    2016-04-01

    The objective of this study was to investigate the pH-dependent solubility and dissolution of weakly basic Biopharmaceutical Classification Systems (BCS) class II drugs, characterized by low solubility and high permeability, using carvedilol, a weak base with a pK a value of 7.8, as a model drug. A series of solubility and in vitro dissolution studies was carried out using media that simulate the gastric and intestinal fluids and cover the physiological pH range of the GI from 1.2 to 7.8. The effect of ionic strength, buffer capacity, and buffer species of the dissolution media on the solubility and dissolution behavior of carvedilol was also investigated. The study revealed that carvedilol exhibited a typical weak base pH-dependent solubility profile with a high solubility at low pH (545.1-2591.4 μg/mL within the pH range 1.2-5.0) and low solubility at high pH (5.8-51.9 μg/mL within the pH range 6.5-7.8). The dissolution behavior of carvedilol was consistent with the solubility results, where carvedilol release was complete (95.8-98.2% released within 60 min) in media simulating the gastric fluid (pH 1.2-5.0) and relatively low (15.9-86.2% released within 240 min) in media simulating the intestinal fluid (pH 6.5-7.8). It was found that the buffer species of the dissolution media may influence the solubility and consequently the percentage of carvedilol released by forming carvedilol salts of varying solubilities. Carvedilol solubility and dissolution decreased with increasing ionic strength, while lowering the buffer capacity resulted in a decrease in carvedilol solubility and dissolution rate.

  12. Genetic evaluation for body condition score in Italian Brown Swiss cattle

    OpenAIRE

    C. Nicoletti; E. Santus; L. Testa; O. Bonetti; A. Rossoni

    2010-01-01

    Body Condition Score (BCS) evaluates the body energy reserve in a cow using a numeric classification. It is possible to use the BCS as an indirect indicator of fertility. The genetic evaluation for BCS in Italian Brown Swiss is performed on 73125 BCS evaluations on the same number of primiparous, daughters of 507 sires. Effect of herd by year goes from -1,02 to +0,94 indicating large differences among herds. The primiparous cows show about 3.2 BCS points at calving, their BCS decreases slight...

  13. Relationship between body condition score at calving and reproductive performance in young postpartum cows grazing native range.

    Science.gov (United States)

    Mulliniks, J T; Cox, S H; Kemp, M E; Endecott, R L; Waterman, R C; Vanleeuwen, D M; Petersen, M K

    2012-08-01

    Body condition score is used as a management tool to predict competency of reproduction in beef cows. Therefore, a retrospective study was performed to evaluate association of BCS at calving with subsequent pregnancy rate, days to first postpartum ovulation, nutrient status (assessed by blood metabolites), and calf BW change in 2- and 3-yr-old cows (n = 351) managed and selected to fit their environment of grazing native range over 6 yr at the Corona Range and Livestock Research Center, Corona, NM. Cows were managed similarly before calving, without manipulation of management, to achieve predetermined BCS at parturition. Palpable BCS (scale of 1 to 9) were determined by 2 experienced technicians before calving. Cows were classified to 1 of 3 BCS groups prior calving: BCS 4 (mean BCS = 4.3 ± 0.02), 5 (mean BCS = 5.0 ± 0.03), or 6 (mean BCS = 5.8 ± 0.06). Cows were weighed weekly after calving and serum was collected once weekly (1 yr) or twice weekly (5 yr) for progesterone analysis to estimate first postpartum ovulation beginning 35 d postpartum. Year effects also were evaluated, with years identified as either above or below average precipitation. Days to first postpartum ovulation did not differ among calving BCS groups (P = 0.93). Pregnancy rates were not influenced by calving BCS (P = 0.83; 92%, 91%, 90% for BCS 4, 5, and 6, respectively). Days to BW nadir was not influenced by BCS at calving (P = 0.95). Cow BW was different at all measuring points (P score did not influence overall pregnancy rates, indicating that young cows can have a reduced BCS and still be reproductively punctual. Therefore, these results indicate that reproductive performance of young cows with reduced BCS may not be affected when managed in extensive range conditions.

  14. Evaluation of body condition score measured throughout lactation as an indicator of fertility in dairy cattle.

    Science.gov (United States)

    Banos, G; Brotherstone, S; Coffey, M P

    2004-08-01

    Body condition score (BCS) records of primiparous Holstein cows were analyzed both as a single measure per animal and as repeated measures per sire of cow. The former resulted in a single, average, genetic evaluation for each sire, and the latter resulted in separate genetic evaluations per day of lactation. Repeated measure analysis yielded genetic correlations of less than unity between days of lactation, suggesting that BCS may not be the same trait across lactation. Differences between daily genetic evaluations on d 10 or 30 and subsequent daily evaluations were used to assess BCS change at different stages of lactation. Genetic evaluations for BCS level or change were used to estimate genetic correlations between BCS measures and fertility traits in order to assess the capacity of BCS to predict fertility. Genetic correlation estimates with calving interval and non-return rate were consistently higher for daily BCS than single measure BCS evaluations, but results were not always statistically different. Genetic correlations between BCS change and fertility traits were not significantly different from zero. The product of the accuracy of BCS evaluations with their genetic correlation with the UK fertility index, comprising calving interval and non-return rate, was consistently higher for daily than for single BCS evaluations, by 28 to 53%. This product is associated with the conceptual correlated response in fertility from BCS selection and was highest for early (d 10 to 75) evaluations.

  15. Assessing and managing body condition score for the prevention of metabolic disease in dairy cows.

    Science.gov (United States)

    Roche, John R; Kay, Jane K; Friggens, Nic C; Loor, Juan J; Berry, Donagh P

    2013-07-01

    Body condition score (BCS) is an assessment of a cow's body fat (and muscle) reserves, with low values reflecting emaciation and high values equating to obesity. The intercalving profile of BCS is a mirror image of the milk lactation profile. The BCS at which a cow calves, her nadir BCS, and the amount of BCS lost after calving are associated with milk production, reproduction, and health. Genetics, peripartum nutrition, and management are factors that likely interact with BCS to determine the risk of health disorders. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Scientific publications on portal vein thrombosis and Budd-Chiari syndrome: a global survey of the literature.

    Science.gov (United States)

    Qi, Xingshun; Jia, Jia; Ren, Weirong; Yang, Man; De Stefano, Valerio; Wang, Juan; Fan, Daiming

    2014-03-01

    Portal vein thrombosis (PVT) and Budd-Chiari syndrome (BCS) are two rare vascular disorders of the liver that can lead to life-threatening complications. We conducted a global survey to systematically analyze the scientific publications in the fields of PVT and BCS. All papers regarding PVT and BCS were identified via the PubMed, EMBASE, and Cochrane library databases. The publication year, country, type of paper, study design, and number of citations were summarized. Good quality papers were defined as those in which a high proportion of homogeneous patients with BCS and/or PVT was observed. We identified 6691 and 4325 papers regarding PVT and BCS, respectively. The number of papers gradually increased over time. Researchers from the USA published the greatest number of papers (PVT: n=1418; BCS: n=888). Clinical studies were the most common type of paper (PVT: n=5395; BCS n=3171), but fewer than half of these observed more than 10 patients (PVT: n=2667/5395; BCS: n=1092/3171). Furthermore, fewer than half of the clinical studies with more than 10 patients were of good quality (PVT: 976/2667; BCS: 466/1092). According to the study design, the good quality papers were classified as cohort studies (PVT: n=865; BCS: n=421), case-control studies (PVT: n=98; BCS: n=45), and randomized controlled trials (PVT: n=13; BCS: n=0). The 5 most frequently cited original articles and guidelines/consensuses were also listed. Despite an increase in the number of papers regarding PVT and BCS over time, most of the papers had a small sample size, suggesting the necessity of large cohort studies or randomized controlled trials.

  17. Higher Volume at Time of Breast Conserving Surgery Reduces Re-Excision in DCIS

    Directory of Open Access Journals (Sweden)

    J. H. Wolf

    2011-01-01

    Full Text Available Purpose. The purpose of this study was to compare the surgical and pathological variables which impact rate of re-excision following breast conserving therapy (BCS with or without concurrent additional margin excision (AM. Methods. The pathology database was queried for all patients with DCIS from January 2004 to September 2008. Pathologic assessment included volume of excision, subtype, size, distance from margin, grade, necrosis, multifocality, calcifications, and ER/PR status. Results. 405 cases were identified and 201 underwent BCS, 151-BCS-AM, and 53-mastectomy. Among the 201 BCS patients, 190 underwent re-excision for close or involved margins. 129 of these were treated with BCS and 61 with BCS-AM (P<.0001. The incidence of residual DCIS in the re-excision specimens was 32% (n=65 for BCS and 22% (n=33 for BCS-AM (P<.05. For both the BCS and the BCS-AM cohorts, volume of tissue excised is inversely correlated to the rate of re-excision (P=.0284. Multifocality (P=.0002 and ER status (P=.0382 were also significant predictors for rate of re-excision and variation in surgical technique was insignificant. Conclusions. The rate of positive margins, re-excision, and residual disease was significantly higher in patients with lower volume of excision. The performance of concurrent additional margin excision increases the efficacy of BCS for DCIS.

  18. Electron-tunneling observation of localized excited states in superconducting manganese-doped lead

    International Nuclear Information System (INIS)

    Tsang, J.; Ginsberg, D.M.

    1980-01-01

    We have made electron-tunneling measurements on a dilute, superconducting lead-manganese alloy. A well-defined structure was observed in the ac-conductance--voltage curves, indicating excited states within the BCS energy gap. These states were partially accounted for by Shiba theory when spin-dependent s-, p-, and d-wave scattering were included. The phase shifts used in doing that were the results of band calculations. The experimental data also show the existence of a broad background density of states in the energy gap, which cannot be accounted for by the theory

  19. Role of body condition score and body weight in the control of seasonal reproduction in Blanca Andaluza goats.

    Science.gov (United States)

    Gallego-Calvo, L; Gatica, M C; Guzmán, J L; Zarazaga, L A

    2014-12-30

    The reproductive activity of 84 female Blanca Andaluza goats was monitored over 17 months to determine the role of body condition score (BCS) and body weight (BW) in its control. Following a 3×2 factorial experimental design, the animals were allocated to three groups: low BCS (≤2.50, n=24), medium BCS (BCS=2.75-3.00, n=31) and high BCS (≥3.25, n=29). The same animals, irrespective of the BCS group categorization, were also divided into two groups depending on BW: low BW (≤40kg, n=44) and high BW (>40kg, n=40). Oestrus was evaluated daily using vasectomised males. The ovulation rate was assessed by trans-rectal ultrasonography after the identification of oestrus. Ovulations were determined by monitoring the plasma progesterone concentration weekly. The BCS and BW were recorded once a week and nutritional status adjusted to maintain the initial differences in BW and BCS between the groups. Both BCS and BW had a significant (at least Preproductive activity recorded in does with a BCS of ≥2.75 and BW of >40kg. No significant interaction between these variables was observed. Some (11.7%) of the does in the groups with animals of BCS≥2.75 had ovulations during seasonal anoestrus. None of the does with a BCS of ≤2.5 had ovulations during seasonal anoestrus. The ovulation rate of the first and last oestrus was influenced by BW (Preproductive seasonality that is clearly and independently modulated by BCS and BW. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Pairing in exotic neutron-rich nuclei near the drip line and in the crust of neutron stars

    Science.gov (United States)

    Pastore, A.; Margueron, J.; Schuck, P.; Viñas, X.

    2013-09-01

    Exotic and drip-line nuclei as well as nuclei immersed in a low-density gas of neutrons in the inner crust of neutron stars are systematically investigated with respect to their neutron pairing properties. This is done using Skyrme density-functional and different pairing forces such as a density-dependent contact interaction and a separable form of a finite-range Gogny interaction. Hartree-Fock-Bogoliubov (HFB) and Bardeen-Cooper-Schrieffer (BCS) theories are compared. It is found that neutron pairing is reduced towards the drip line while overcast by strong shell effects. Furthermore, resonances in the continuum can have an important effect counterbalancing the tendency of reduction and leading to a persistence of pairing at the drip line. It is also shown that in these systems the difference between HFB and BCS approaches can be quantitatively large.

  1. Effect of induced body condition score differences on physiological response, productive and reproductive performance of Malpura ewes kept in a hot, semi-arid environment.

    Science.gov (United States)

    Sejian, V; Maurya, V P; Naqvi, S M K; Kumar, D; Joshi, A

    2010-04-01

    This study was undertaken to study the influence of induced body condition score (BCS) differences on physiological response, productive and reproductive performance of Malpura ewes to optimise BCS for these ewes for maximising production making it economically viable. The study was conducted for a period of 1 year using thirty healthy Malpura ewes (2-4 year old). The animals were randomly divided and different BCS was induced within three groups named Group I (BCS 2.5; n = 10), Group II (BCS 3.0-3.5; n = 10) and Group III (BCS 4.0; n = 10). The parameters included in the study were allometric measurements, physiological response, wool yield and reproductive performance. BCS had a significant influence on allometric measurements, respiration rate and different reproductive parameters studied, while wool production differed significantly during spring and non-significantly during autumn. The results revealed that the reproductive performance of Malpura ewes with a BCS of 3.0-3.5 was better in comparison with the groups with lower and higher BCS. It may be concluded from this study that an active management of breeding sheep flock to achieve a BCS of 3.0-3.5 may prove to result in an economically viable return from these flocks.

  2. Genetics of body condition score as an indicator of dairy cattle fertility. A review

    Directory of Open Access Journals (Sweden)

    Bastin, C.

    2013-01-01

    Full Text Available Body condition score (BCS is a subjective measure of the amount of metabolizable energy stored in a live animal. Change in BCS of dairy cows is considered to be an indicator of the extent and the duration of postpartum negative energy balance. Although change in BCS over lactation is lowly heritable, heritability estimates of level of BCS range from 0.20 to 0.50. Also, BCS tends to be more heritable in mid-lactation indicating that genetic differences are more related to how well cows recover from the negative energy balance state. BCS measurements are generally highly correlated within and between lactations. Genetic correlations with BCS are unfavorable for milk, fat, and protein yield, suggesting that genetically superior producers tend to have lower BCS, especially during the lactation. Genetic correlations are generally moderate and favorable with fertility indicating that cows with higher levels of BCS would have a greater chance to conceive after insemination and fewer number of days when not pregnant. Because direct selection to improve fertility might be complicated by several factors, selection for higher levels of BCS, especially in mid-lactation, appears to be a good option to indirectly improve fertility in dairy cows.

  3. AN EDUCATIONAL THEORY MODEL--(SIGGS), AN INTEGRATION OF SET THEORY, INFORMATION THEORY, AND GRAPH THEORY WITH GENERAL SYSTEMS THEORY.

    Science.gov (United States)

    MACCIA, ELIZABETH S.; AND OTHERS

    AN ANNOTATED BIBLIOGRAPHY OF 20 ITEMS AND A DISCUSSION OF ITS SIGNIFICANCE WAS PRESENTED TO DESCRIBE CURRENT UTILIZATION OF SUBJECT THEORIES IN THE CONSTRUCTION OF AN EDUCATIONAL THEORY. ALSO, A THEORY MODEL WAS USED TO DEMONSTRATE CONSTRUCTION OF A SCIENTIFIC EDUCATIONAL THEORY. THE THEORY MODEL INCORPORATED SET THEORY (S), INFORMATION THEORY…

  4. Response of cyprid specific genes to natural settlement cues in the barnacle Balanus (=Amphibalanus) amphitrite

    KAUST Repository

    Li, Honglei; Thiyagarajan, Vengatesen; Qian, Pei Yuan

    2010-01-01

    Quantitative real-time PCR was used to further our understanding of the molecular processes involved in the attachment and metamorphosis of larval barnacles. We report the effects of natural settlement cues (microbial biofilms and conspecific settlement-inducing factor) on the expression profiles of six barnacle cyprid specific (bcs) genes in cyprids of the barnacle Balanus (=Amphibalanus) amphitrite Darwin. Genes bcs-1 to bcs-5 all showed marked decreases in their expression between initial cyprid attachment and the completion of metamorphosis, whereas bcs-6 showed significant up-regulation. Generally, settlement cues exerted no significant effect on the decreasing trend of bcs-1 to bcs-5 expression during attachment and metamorphosis. However, the expression of bcs-6 increased prior to cyprid attachment in response to both settlement cues. This elevated expression of bcs-6 gene indicates the importance and key regulatory role of this specific gene to larval attachment and metamorphosis in this barnacle species. © 2010 Elsevier B.V. All rights reserved.

  5. Response of cyprid specific genes to natural settlement cues in the barnacle Balanus (=Amphibalanus) amphitrite

    KAUST Repository

    Li, Honglei

    2010-06-01

    Quantitative real-time PCR was used to further our understanding of the molecular processes involved in the attachment and metamorphosis of larval barnacles. We report the effects of natural settlement cues (microbial biofilms and conspecific settlement-inducing factor) on the expression profiles of six barnacle cyprid specific (bcs) genes in cyprids of the barnacle Balanus (=Amphibalanus) amphitrite Darwin. Genes bcs-1 to bcs-5 all showed marked decreases in their expression between initial cyprid attachment and the completion of metamorphosis, whereas bcs-6 showed significant up-regulation. Generally, settlement cues exerted no significant effect on the decreasing trend of bcs-1 to bcs-5 expression during attachment and metamorphosis. However, the expression of bcs-6 increased prior to cyprid attachment in response to both settlement cues. This elevated expression of bcs-6 gene indicates the importance and key regulatory role of this specific gene to larval attachment and metamorphosis in this barnacle species. © 2010 Elsevier B.V. All rights reserved.

  6. Reduced Cortisol and Metabolic Responses of Thin Ewes to an Acute Cold Challenge in Mid-Pregnancy: Implications for Animal Physiology and Welfare

    Science.gov (United States)

    Verbeek, Else; Oliver, Mark Hope; Waas, Joseph Rupert; McLeay, Lance Maxwell; Blache, Dominique; Matthews, Lindsay Ross

    2012-01-01

    Background Low food availability leading to reductions in Body Condition Score (BCS; 0 indicates emaciation and 5 obesity) in sheep often coincides with low temperatures associated with the onset of winter in New Zealand. The ability to adapt to reductions in environmental temperature may be impaired in animals with low BCS, in particular during pregnancy when metabolic demand is higher. Here we assess whether BCS affects a pregnant animal's ability to cope with cold challenges. Methods Eighteen pregnant ewes with a BCS of 2.7±0.1 were fed to attain low (LBC: BCS2.3±0.1), medium (MBC: BCS3.2±0.2) or high BCS (HBC: BCS3.6±0.2). Shorn ewes were exposed to a 6-h acute cold challenge in a climate-controlled room (wet and windy conditions, 4.4±0.1°C) in mid-pregnancy. Blood samples were collected during the BCS change phase, acute cold challenge and recovery phase. Results During the BCS change phase, plasma glucose and leptin concentrations declined while free fatty acids (FFA) increased in LBC compared to MBC (Pewes (Pewes (Pewes (Pewes while remaining unchanged in LBC ewes (Pewes (Pewes (Pewes were able to increase Tcore and mobilize glucose, low BCS animals had considerably reduced cortisol and metabolic responses to a cold challenge in mid-pregnancy, suggesting that their ability to adapt to cold challenges through some of the expected pathways was reduced. PMID:22662144

  7. Shell-model Monte Carlo simulations of the BCS-BEC crossover in few-fermion systems

    DEFF Research Database (Denmark)

    Zinner, Nikolaj Thomas; Mølmer, Klaus; Özen, C.

    2009-01-01

    We study a trapped system of fermions with a zero-range two-body interaction using the shell-model Monte Carlo method, providing ab initio results for the low particle number limit where mean-field theory is not applicable. We present results for the N-body energies as function of interaction...

  8. Phase structure and critical properties of an abelian gauge theory

    Energy Technology Data Exchange (ETDEWEB)

    Mo, Sjur

    2001-12-01

    The main new results are presented in the form of three papers at the end of this thesis. The main topic is Monte-Carlo studies of the phase structure and critical properties of the phenomenological Ginzburg-Landau model, i.e. an abelian gauge theory. However, the first paper is totally different and deals with microscopic theory for lattice-fermions in a magnetic field. Paper I is about ''Fermion-pairing on a square lattice in extreme magnetic fields''. We consider the Cooper-problem on a two-dimensional, square lattice with a uniform, perpendicular magnetic field. Only rational flux fractions are considered. An extended (real-space) Hubbard model including nearest and next nearest neighbor interactions is transformed to ''k-space'', or more precisely, to the space of eigenfunctions of Harper's equation, which constitute basis functions of the magnetic translation group for the lattice. A BCS-like truncation of the interaction term is performed. Expanding the interactions in the basis functions of the irreducible representations of the point group C{sub 4{nu}} of the square lattice simplify calculations. The numerical results indicate enhanced binding compared to zero magnetic field, and thus re-entrant superconducting pairing at extreme magnetic fields, well beyond the point where the usual semi-classical treatment of the magnetic field breaks down. Paper II is about the ''Hausdorff dimension of critical fluctuations in abelian gauge theories''. Here we analyze the geometric properties of the line-like critical fluctuations (vortex loops) in the Ginzburg-Landau model in zero magnetic background field. By using a dual description, we obtain scaling relations between exponents of geometric arid thermodynamic nature. In particular we connect the anomalous scaling dimension {eta} of the dual matter field to the Hausdorff or fractal dimension D{sub H} of the critical fluctuations, in the original model

  9. String theory or field theory?

    International Nuclear Information System (INIS)

    Marshakov, Andrei V

    2002-01-01

    The status of string theory is reviewed, and major recent developments - especially those in going beyond perturbation theory in the string theory and quantum field theory frameworks - are analyzed. This analysis helps better understand the role and place of string theory in the modern picture of the physical world. Even though quantum field theory describes a wide range of experimental phenomena, it is emphasized that there are some insurmountable problems inherent in it - notably the impossibility to formulate the quantum theory of gravity on its basis - which prevent it from being a fundamental physical theory of the world of microscopic distances. It is this task, the creation of such a theory, which string theory, currently far from completion, is expected to solve. In spite of its somewhat vague current form, string theory has already led to a number of serious results and greatly contributed to progress in the understanding of quantum field theory. It is these developments which are our concern in this review. (reviews of topical problems)

  10. Comparison of a classical with a highly formularized body condition scoring system for dairy cattle.

    Science.gov (United States)

    Isensee, A; Leiber, F; Bieber, A; Spengler, A; Ivemeyer, S; Maurer, V; Klocke, P

    2014-12-01

    Body condition scoring is a common tool to assess the subcutaneous fat reserves of dairy cows. Because of its subjectivity, which causes limits in repeatability, it is often discussed controversially. Aim of the current study was to evaluate the impact of considering the cows overall appearance on the scoring process and on the validity of the results. Therefore, two different methods to reveal body condition scores (BCS), 'independent BCS' (iBCS) and 'dependent BCS' (dBCS), were used to assess 1111 Swiss Brown Cattle. The iBCS and the dBCS systems were both working with the same flowchart with a decision tree structure for visual and palpatory assessment using a scale from 2 to 5 with increment units of 0.25. The iBCS was created strictly complying with the defined frames of the decision tree structure. The system was chosen due to its formularized approach to reduce the influence of subjective impressions. By contrast, the dBCS system, which was in line with common practice, had a more open approach, where - besides the decision tree - the overall impression of the cow's physical appearance was taken into account for generating the final score. Ultrasound measurement of the back fat thickness (BFT) was applied as a validation method. The dBCS turned out to be the better predictor of BFT, explaining 67.3% of the variance. The iBCS was only able to explain 47.3% of the BFT variance. Within the whole data set, only 31.3% of the animals received identical dBCS and iBCS. The pin bone region caused the most deviations between dBCS and iBCS, but also assessing the pelvis line, the hook bones and the ligaments led to divergences in around 20% of the scored animals. The study showed that during the assessment of body condition a strict adherence to a decision tree is a possible source of inexact classifications. Some body regions, especially the pin bones, proved to be particularly challenging for scoring due to difficulties in assessing them. All the more, the inclusion

  11. Superconductivity in hydrogen-rich materials at high pressures

    Energy Technology Data Exchange (ETDEWEB)

    Drozdov, Alexander

    2016-07-01

    A room temperature superconductor is probably one of the most desired systems in solid state physics. The highest critical temperature (T{sub c}) that has been achieved so far is in the copper oxide system: 133 kelvin (K) at ambient pressure ([82]Schilling et al. 1993) and 160 K under pressure ([42]Gao et al. 1994). The nature of superconductivity in the cuprates and in the recently discovered iron-based superconductor family (T{sub c}=57 K) is still not fully understood. In contrast, there is a class of superconductors which is well-described by the Bardeen, Cooper, Schrieffer (BCS) theory - conventional superconductors. Great efforts were spent in searching for high-temperature (T{sub c} > 77 K) conventional superconductor but only T{sub c} = 39 K has been reached in MgB2 ([68]Nagamatsu et al. 2001). BCS theory puts no bounds for T{sub c} as follows from Eliashberg's formulation of BCS theory. T{sub c} can be high, if there is a favorable combination of high-frequency phonons, strong electron-phonon coupling, and a high density of states. It does not predict however in which materials all three parameters are large. At least it gives a clear indication that materials with light elements are favorable as light elements provide high frequencies in the phonon spectrum. The lightest element is hydrogen, and Ashcroft made a first prediction that metallic hydrogen will be a high-temperature superconductor ([6]Ashcroft 1968). As pressure of hydrogen metallization was too high (about 400-500 GPa) for experimental techniques then he proposed that compounds dominated by hydrogen (hydrides) also might be good high temperature superconductors ([6]Ashcroft 1968; [7]Ashcroft 2004). A lot of the followed calculations supported this idea. T{sub c} in the range of 50-235 kelvin was predicted for many hydrides. Unfortunately, only a moderate T{sub c} of 17 kelvin has been observed experimentally ([27]Eremets et al. 2008) so far. A goal of the present work is to find a

  12. String Theory and M-Theory

    Science.gov (United States)

    Becker, Katrin; Becker, Melanie; Schwarz, John H.

    String theory is one of the most exciting and challenging areas of modern theoretical physics. This book guides the reader from the basics of string theory to recent developments. It introduces the basics of perturbative string theory, world-sheet supersymmetry, space-time supersymmetry, conformal field theory and the heterotic string, before describing modern developments, including D-branes, string dualities and M-theory. It then covers string geometry and flux compactifications, applications to cosmology and particle physics, black holes in string theory and M-theory, and the microscopic origin of black-hole entropy. It concludes with Matrix theory, the AdS/CFT duality and its generalizations. This book is ideal for graduate students and researchers in modern string theory, and will make an excellent textbook for a one-year course on string theory. It contains over 120 exercises with solutions, and over 200 homework problems with solutions available on a password protected website for lecturers at www.cambridge.org/9780521860697. Comprehensive coverage of topics from basics of string theory to recent developments Ideal textbook for a one-year course in string theory Includes over 100 exercises with solutions Contains over 200 homework problems with solutions available to lecturers on-line

  13. String theory or field theory?

    International Nuclear Information System (INIS)

    Marshakov, A.V.

    2002-01-01

    The status of string theory is reviewed, and major recent developments - especially those in going beyond perturbation theory in the string theory and quantum field theory frameworks - are analyzed. This analysis helps better understand the role and place of experimental phenomena, it is emphasized that there are some insurmountable problems inherent in it - notably the impossibility to formulate the quantum theory of gravity on its basis - which prevent it from being a fundamental physical theory of the world of microscopic distances. It is this task, the creation of such a theory, which string theory, currently far from completion, is expected to solve. In spite of its somewhat vague current form, string theory has already led to a number of serious results and greatly contributed to progress in the understanding of quantum field theory. It is these developments, which are our concern in this review [ru

  14. Bleaching effects of massecuite on some properties of crystallized sugar beet and milk chocolate bars produced.

    Science.gov (United States)

    Sadjadi, F Seyed; Honarvar, M; Kalbasi-Ashtari, A; Motaghian, P

    2018-04-01

    Four kinds of bleached, unbleached, second and third crystal sugars (BCS, UCS, SCS and TCS) were made from different massecuites in a sugar-beet factory, and their physiochemical (polarization, invert sugar, colorants, pH, ash and SO 2 ), microbiological and functional properties were measured. While the polarization of UCS, SCS and TCS were lower than BCS; their invert sucrose, colorants, pH and ash contents were significantly higher than BCS. The phenols and betaine of BCS, UCS, SCS, and TCS were 144, 401, 384 and 673 (mg/100 g); and 244, 791, 4662, and 6589 (mg/100 g); respectively. Whereas the phenol of milk chocolate bars (MCB) made with UCS, SCS, and TCS were only 10% higher than MCB completed with BCS; their betaine contents were substantially (up to 16 times) higher than the ones finished with BCS. Sensory evaluation showed that the MCB prepared with three sugars including UCS, SCS and TCS had significantly higher glossiness, brittleness, flavor and mouth feel than those made with BCS. The greater colorants, ash content and inverted sugars of UCS, SCS and TCS (in comparison with BCS) made considerable improvements in the glossiness, flavor and brittleness of MCB, respectively. BCS had 8 ppm of toxic sulfur; whereas, UCS, SCS and TCS had no detectable sulfur and significantly higher beneficial copper content than BCS. No pathogenic microorganism were detected in UCS, SCS, TCS or their subsequent MCB. Our results highly recommend using UCS, SCS and TCS instead of BCS in food products (such as MCB) due to their higher health benefits.

  15. Comparison of performance of partial prestressed beam-column subassemblages made of reactive powder concrete and normal concrete materials using finite element models

    Science.gov (United States)

    Nurjannah, S. A.; Budiono, B.; Imran, I.; Sugiri, S.

    2016-04-01

    Research on concrete material continues in several countries and had produced a concrete type of Ultra High Performance Concrete (UHPC) which has a better compressive strength, tensile strength, flexural strength, modulus of elasticity, and durability than normal concrete (NC) namely Reactive Powder Concrete (RPC). Researches on structures using RPC material showed that the RPC structures had a better performance than the NC structures in resisting gravity and lateral cyclic loads. In this study, an experiment was conducted to apply combination of constant axial and lateral cyclic loads to a prototype of RPC interior partial prestressed beam-column subassemblage (prototype of BCS-RPC) with a value of Partial Prestressed Ratio (PPR) of 31.72% on the beam. The test results were compared with finite element model of beam-column subassemblage made of RPC by PPR of 31.72% (BCS-RPC-31.72). Furthermore, there was BCS-RPC modeling with PPR of 21.39% (BCS-RPC-21.39) and beam-column subassemblages made of NC materials modeling with a value of PPR at 21.09% (BCS-NC-21.09) and 32.02% (BCS-NC-32.02). The purpose of this study was to determine the performance of the BCS-RPC models compared to the performance of the BCS-NC models with PPR values below and above 25%, which is the maximum limit of permitted PPR. The results showed that all models of BCS-RPC had a better performance than all models of BCS-NC and the BCS-RPC model with PPR above 25% still behaved ductile and was able to dissipate energy well.

  16. Impact of canine overweight and obesity on health-related quality of life.

    Science.gov (United States)

    Yam, P S; Butowski, C F; Chitty, J L; Naughton, G; Wiseman-Orr, M L; Parkin, T; Reid, J

    2016-05-01

    Canine obesity is increasing in prevalence in the UK and raises concerns about dog welfare. This study compares the health-related quality of life (HRQL) of dogs of varying body condition: overweight and obese (BCS 4 and 5) versus non-overweight dogs (BCS 2 and 3), obese (BCS 5) versus non-overweight (BCS 2 and 3) and an overall comparison between all four BCS (BCS 2, 3, 4 and 5) using a novel, validated HRQL instrument which is both web and mobile tablet/phone app based. Of 271 dog owners who were approached, 174 completed a web-based instrument (2013) or a mobile tablet app instrument (2014) during the summers of 2013 and 2014. Automatically generated scores in four domains of HRQL (energetic/enthusiastic, happy/content, active/comfortable, calm/relaxed) were compared for dogs with each of the body condition scores (BCS 2-5). For all body condition scores a statistically significant difference was found between the HRQL scores in two of the domains: energetic/enthusiastic (p=0.02) and active comfortable (p=0.004). When BCS 2 and 3 were compared to BCS 4 and 5, statistical significance was found in the same two domains - energetic/enthusiastic (p=0.01) and active comfortable (p=0.001) - as it was in comparison of non-overweight (BCS 2 and 3) compared to obese dogs (BCS 5): energetic/enthusiastic (p=0.012) and active comfortable (p=0.004). These results suggest that overweight and obese dogs have a reduced HRQL in two of the domains compared to non-overweight dogs, and that differences in HRQL are detectable between BCS scores 2, 3, 4 and 5. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. 4. MESOSCOPIC SUPERCONDUCTIVITY: Some signatures of quantum chaos on dirty superconductors

    Science.gov (United States)

    Zhou, F.

    2001-10-01

    The Anderson theory of dirty superconductivity was established a few years after the discovery of the BCS wave function. Disregarding the rich properties in the one-particle energy spectrum in dirty limit, the theory claimed that the ground state condensate is translationally invariant and free from Toulouse type of frustrations. This theory also set down the foundation of dirty superconductivity in the presence of external fields. In this talk, I demonstrate the failure of the Anderson theory in amorphous superconducting films in general and its connection with Wigner-Dyson surmise. I will discuss the Chandrasekar-Glogston limit in which the nodes in one-particle wave functions are shown to result in a novel superconducting glass phase. I will also discuss why nature has tolerated the failure.

  18. Genetics of body condition score as an indicator of dairy cattle fertility. A review

    OpenAIRE

    Bastin, C.; Gengler, N.

    2013-01-01

    Body condition score (BCS) is a subjective measure of the amount of metabolizable energy stored in a live animal. Change in BCS of dairy cows is considered to be an indicator of the extent and the duration of postpartum negative energy balance. Although change in BCS over lactation is lowly heritable, heritability estimates of level of BCS range from 0.20 to 0.50. Also, BCS tends to be more heritable in mid-lactation indicating that genetic differences are more related to how well cows recove...

  19. Survey on breast cancer patients in China toward breast-conserving surgery.

    Science.gov (United States)

    Zhang, Li; Jiang, Ming; Zhou, Yi; Du, Xiao-Bo; Yao, Wen-Xiu; Yan, Xi; Jiang, Yu; Zou, Li-Qun

    2012-05-01

    We sought to investigate attitudes toward breast-conserving therapy (BCS) in early-stage breast cancer (EBC) patients from P. R. China and assess the factors influencing their decision. There exists geographical difference in decision to perform mastectomy or BCS for EBC patients. To date, there has been no report on attitudes toward BCS or factors influencing the surgical choice in mainland China. A structured questionnaire was delivered to 1800 EBC patients. The questionnaire elicited information about general patients' characteristics, attitudes toward BCS, the roles of doctors and spouses, the levels of understanding of BCS, and the reasons for their preferences. Of 1590 participants, only 7.3% anticipated BCS and this was significantly associated with patient age, income, occupation, martial status, education, levels of self-understanding of the disease, and doctors' and spouses' suggestions (Pwomen (39.2%), even if given another opportunity, only 32.5% of patients preferred to choose it. Moreover, the level of understanding BCS among patients is low (well-known: less-known: never-heard, 2.3 vs 47.4 vs 13.3%). These results suggested that Chinese EBC patients lack accurate and comprehensive understanding of BCS. More efforts are needed to educate breast cancer patients in mainland China toward BCS. Copyright © 2011 John Wiley & Sons, Ltd.

  20. Josephson effect in high-Tc superconductors and in structures using them

    International Nuclear Information System (INIS)

    Kupriyanov, M.Yu.; Likharev, K.K.

    1990-01-01

    A review of the investigations of the Josephson effect in HTS materials and HTS Josephson structures is represented. The influence of the synthesis conditions and a surface etching on the surface properties of the HTS/Ag(Au) are briefly discussed. On the basis of these results the experimental data obtained in various types of the Josephson junctions (point contacts, tunnel junctions, weak links, break and bulk junctions and crystal type break junctions) are considered. These data are compared with theoretical results obtained from different BCS models of the Josephson junctions. It is concluded that now it is impossible to make either the conclusion on the applicability of the BCS theory for HTS superconductors or the unambiguous identification of the principal physical structure of the junctions. The directions of the future experimental investigations of the Josephson effect in HTS tunnel junctions and weak links are discussed

  1. Commissioning results of the HZB quadrupole resonator

    CERN Document Server

    Kleindienst, Raphael; Knobloch, Jens; Kugeler, Oliver

    2015-01-01

    Recent cavity results with niobium have demonstrated the necessity of a good understanding of both the BCS and residual resistance. For a complete picture and comparison with theory, it is essential that one can measure the RF properties as a function of field, temperature, frequency and ambient magnetic field. Standard cavity measurements are limited in their ability to change all parameters freely and in a controlled manner. On the other hand, most sample measurement setups operate at fairly high frequency, where the surface resistance is always BCS dominated. The quadrupole resonator, originally developed at CERN, is ideally suited for characterization of samples at typical cavity RF frequencies. We report on a modified version of the QPR with improved RF figures of merit for high-field operation. Experimental challenges in the commissioning run and alternate designs for simpler sample changes are shown alongside measurement results of a large grain niobium sample.

  2. Crystallographic snapshot of cellulose synthesis and membrane translocation.

    Science.gov (United States)

    Morgan, Jacob L W; Strumillo, Joanna; Zimmer, Jochen

    2013-01-10

    Cellulose, the most abundant biological macromolecule, is an extracellular, linear polymer of glucose molecules. It represents an essential component of plant cell walls but is also found in algae and bacteria. In bacteria, cellulose production frequently correlates with the formation of biofilms, a sessile, multicellular growth form. Cellulose synthesis and transport across the inner bacterial membrane is mediated by a complex of the membrane-integrated catalytic BcsA subunit and the membrane-anchored, periplasmic BcsB protein. Here we present the crystal structure of a complex of BcsA and BcsB from Rhodobacter sphaeroides containing a translocating polysaccharide. The structure of the BcsA-BcsB translocation intermediate reveals the architecture of the cellulose synthase, demonstrates how BcsA forms a cellulose-conducting channel, and suggests a model for the coupling of cellulose synthesis and translocation in which the nascent polysaccharide is extended by one glucose molecule at a time.

  3. Searching for superconductors with high critical temperature

    Energy Technology Data Exchange (ETDEWEB)

    Chao, C

    1977-08-18

    Critical temperature of superconductors can be and must be raised so that their range of application can be broadened. It was estimated that, in 3 to 5 years, superconductor electric generators might be used in nuclear submarines and/or other applications where the requirements of small volume and light weight are critical. The BCS theory was recapitulated. Possible methods of achieving higher critical temperature were proposed and discussed.

  4. Intelligence: Pre-Theory and Post-Theory

    Directory of Open Access Journals (Sweden)

    James R. Flynn

    2014-02-01

    Full Text Available Defining “intelligence” exemplifies a mistake that has historical precedent: confusing the role of pre-theory and post-theory definitions. In every area, pre-theory concepts give broad directions for investigation: are the movements of heavenly bodies affected by the existence of other heavenly bodies? Post-theory concepts add precision and predictability. The mistake occurs when a successful theory like Newton’s demands that its peculiar and precise theory-imbedded concept forbids competing theories: Einstein was impossible (warping of space so long as it was assumed that all theories must be in accord with Newton’s concept (attraction across space. In psychology, Arthur Jensen made the same mistake. He gave his theory-embedded concept of g the role of executioner: the significance of every phenomenon had to be interpreted by its compatibility with g; and thus trivialized the significance of IQ gains over time. This is only one instance of a perennial demand: give us a precise definition of “intelligence” to guide our research. However, precision comes after research has generated a theory and its very precision stifles competing research. Be happy with a broad definition on the pre-theory level that lets many competing theories bloom: pre-theory precision equals post-theory poverty.

  5. Graphene-based carbons as supercapacitor electrodes with bicontinuous, porous polyacrylonitrile

    Science.gov (United States)

    Kim, Bit-Na; Yang, Young Suk; You, In-Kyu

    2017-07-01

    In this study, we fabricated a bicontinuous carbon structure (BCS) with high porosity and a loosely connected framework structure. The role of the BCS is to support a concrete supercapacitor active electrode structure. Poly(acrylonitrile) was used as a precursor for the BCS material, which was a porous polymer monolith carbonized by heat treatment (at 1100 °C). The BCS was prepared by mixing with an active material, graphene or an activated carbon. The mixed materials were used as an electrode material in a supercapacitor. The BCS13 + AC sample (∼107.5 F/g) showed a higher specific capacitance than the commercial activated carbon cell (∼76 F/g). The BCS13 + graphene sample (∼75 F/g) also exhibited a higher specific capacitance than the graphene cell (∼49 F/g). This BCS monolith had many macro- and micropores in its structure, enabling fast electrolyte ion movement and excellent electrochemical performance with a low equivalent series resistance (ESR).

  6. Does ECG influence the conception rate Nelore cows presenting different body condition scores submitted to the same timed-AI protocol?

    Directory of Open Access Journals (Sweden)

    Erika Aline Ribeiro Dias

    2013-03-01

    Full Text Available The aim of this study was to evaluate the conception rate (CR of multiparous Nelore cows presenting different body condition scores (BCS, which were submitted to the same Timed-AI protocol with equine chorionic gonadotrophin (eCG. A total of 1574 cows were inseminated, between 40 and 50 days postpartum. During insemination (timed-AI, all data regarding to bull (n=8, inseminator (n=3 and BCS (1 to 5 were recorded. The pregnancy diagnosis was performed, by ultrasonography, 40 days after timed-AI. No effect (P>0.05 of inseminator or bull was observed. No statistical difference was also observed between the groups of animals with different BCS. The animals with lower BCS (Group 1 = BCS 1.5 to 2.0; n = 139 had a CR of 47.4%. The animals with BCS from 2.5 to 2.75 (Group 2; n = 741 and BCS from 3.0 to 3.25 (Group 3; n = 463 had a CR of 47.6% and 51.2%, respectively. The animals with higher BCS (Group 4 = BCS 3.5 to 4.0; n = 231 had a CR of 45.3% (P > 0.05. It was concluded that conception rates were similar between the animals presenting different BCS in the herd, likely because the eCG minimized the effects of low LH pulsatility in animals presenting reduced nutritional condition. However, other studies are recommended to verify the real need of using eCG in animals with body condition exceeding 3.5.

  7. The pattern of LH secretion and the ovarian response to the 'ram effect' in the anoestrous ewe is influenced by body condition but not by short-term nutritional supplementation.

    Science.gov (United States)

    Scaramuzzi, R J; Oujagir, L; Menassol, J-B; Freret, S; Piezel, A; Brown, H M; Cognié, J; Fabre Nys, C

    2014-10-01

    In sheep, the 'ram effect' induces out-of-season fertility and good nutrition increases prolificacy. This experiment determined if fatness or short-term nutritional supplementation modified the response to the 'ram effect'. A group of 48 Île-de-France ewes were fed diets that produced groups with body-condition scores (BCS) of >3.0 and <2.0. Within each BCS group animals were supplemented daily with 500g of lupins from Day -5 to Day 0 (ram introduction) resulting in four groups: low BCS, supplemented (n=7) and non-supplemented (n=8) and high BCS, supplemented (n=12) and non-supplemented (n=11). The blood concentrations of glucose and insulin and the LH response to gonadotrophin-releasing hormone (GnRH) were determined. After the 'ram effect' the pattern of LH pulsatility, the LH surge and ovarian responses were analysed. Low BCS ewes had lower glucose and insulin (P<0.001) and supplementation increased both (P≤0.001). The increase in LH induced by GnRH was reduced in low BCS ewes (P=0.015) but it was not affected by supplementation. Similarly, LH pulsatility was reduced in low BCS ewes (P<0.05). The LH surge and ovarian cyclicity were not affected but the follow-up cycle was delayed (P=0.034) and progesterone was reduced (P=0.029) in low BCS ewes. There was an effect of BCS on ovulation rate (P<0.05). These results show that the BCS can modify the response to the 'ram effect' and that supplementation has little effect on this response.

  8. Assessment of body fat in the pony: part I. Relationships between the anatomical distribution of adipose tissue, body composition and body condition.

    Science.gov (United States)

    Dugdale, A H A; Curtis, G C; Harris, P A; Argo, C Mc

    2011-09-01

    Evaluation of equine body fat content is important for nutritional and clinical purposes. However, our understanding of total body fat and its regional distribution in the body is sparse. Currently, body fat evaluation relies on the subjective assessment of body condition score (BCS), which has never been validated against 'gold standard' chemical analysis or dissection measurements in ponies. To define the relationships between subjective (BCS), objective (morphometric) indices of body fat and 'gold standard' measurements of actual body composition. BCS and morphometry offer valid, noninvasive methods for determination of body fat in equids. Seven mature (mean ± s.e. 13 ± 3 years, 212 ± 14 kg, BCS 1.25-7/9), Welsh Mountain pony mares, destined for euthanasia (for nonresearch purposes), were used. For all ponies, body mass (BM), BCS and various morphometric measurements were recorded. Following euthanasia, all ponies were systematically dissected. Discrete white adipose tissue (WAT) depots were independently described. Gross, body chemical composition was determined by proximate analyses. Total somatic soft tissues increased linearly (r(2) = 1.00), whereas body WAT content (1-26% live BM) increased exponentially (r(2) = 0.96), with BCS. WAT was equally distributed between internal and external sites in all animals irrespective of BCS. Nuchal fat was a poor predictor of total WAT (r(2) = 0.66). Periorbital WAT did not alter with BCS (r(2) = 0.01). Heart girth:withers height and ultrasonic retroperitoneal fat depth were closely associated with total, chemically-extracted lipid which comprised 1-29% live BM (r(2) = 0.91 and 0.88, respectively). The exponential relationship between BCS and total body WAT/lipid suggests that BCS is unlikely to be a sensitive index of body fat for animals in moderate-obese states. Morphometric measurements (body girths and retroperitonel fat depth) may be useful to augment subjective BCS systems. © 2011 EVJ Ltd.

  9. Transfer of Downy Mildew Resistance from Wild Basil (Ocimum americanum) to Sweet Basil (O. basilicum).

    Science.gov (United States)

    Ben-Naim, Yariv; Falach, Lidan; Cohen, Yigal

    2018-01-01

    Sweet basil (Ocimum basilicum) is susceptible to downy mildew caused by the oomycete foliar pathogen Peronospora belbahrii. No resistant varieties of sweet basil are commercially available. Here, we report on the transfer of resistance gene Pb1 from the highly resistant tetraploid wild basil O. americanum var. americanum (PI 500945, 2n = 4x = 48) to the tetraploid susceptible O. basilicum 'Sweet basil' (2n = 4x = 48). F1 progeny plants derived from the interspecific hybridization PI 500945 × Sweet basil were resistant, indicating that the gene controlling resistance (Pb1) is dominant, but sterile due to the genetic distance between the parents. Despite their sterility, F1 plants were pollinated with the susceptible parent and 115 first backcross generation to the susceptible parent (BCs1) embryos were rescued in vitro. The emerging BCs1 plants segregated, upon inoculation, 5:1 resistant/susceptible, suggesting that resistance in F1 was controlled by a pair of dominant genes (Pb1A and Pb1A'). Thirty-one partially fertile BCs1 plants were self-pollinated to obtain BCs1-F2 or were backcrossed to Sweet basil to obtain the second backcross generation to the susceptible parent (BCs2). In total, 1 BCs1-F2 and 22 BCs2 progenies were obtained. The BCs1-F2 progeny segregated 35:1 resistant/susceptible, as expected from a tetraploid parent with two dominant resistant genes. The 22 BCs2 progenies segregated 1:1 resistant/susceptible (for a BCs1 parent that carried one dominant gene for resistance) or 5:1 (for a BCs1 parent that carried two dominant genes for resistance) at a ratio of 4:1. The data suggest that a pair of dominant genes (Pb1A and Pb1A') residing on a two homeologous chromosomes is responsible for resistance of PI 500945 against P. belbahrii.

  10. Body condition score at parturition and postpartum supplemental fat effects on cow and calf performance.

    Science.gov (United States)

    Lake, S L; Scholljegerdes, E J; Atkinson, R L; Nayigihugu, V; Paisley, S I; Rule, D C; Moss, G E; Robinson, T J; Hess, B W

    2005-12-01

    Three-year-old Angus x Gelbvieh beef cows nutritionally managed to achieve a BCS of 4 +/- 0.07 (479.3 +/- 36.3 kg of BW) or 6 +/- 0.07 (579.6 +/- 53.1 kg of BW) at parturition were used in a 2-yr experiment (n = 36/yr) to determine the effects of prepartum energy balance and postpartum lipid supplementation on cow and calf performance. Beginning 3 d postpartum, cows within each BCS were assigned randomly to be fed hay and a low-fat control supplement or supplements with either high-linoleate cracked safflower seeds or high-oleate cracked safflower seeds until d 60 of lactation. Diets were formulated to be isonitrogenous and isocaloric, and safflower seed supplements were provided to achieve 5% of DMI as fat. Ultrasonic 12th rib fat and LM area were lower (P condition over the course of the study, whereas cows in BCS 6 lost condition. No differences (P = 0.44 to 0.71) were detected for milk yield, milk energy, milk fat percentage, or milk lactose percentage because of BCS; however, milk protein percentage was less (P = 0.03) for BCS 4 cows. First-service conception rates did not differ (P = 0.22) because of BCS at parturition, but overall pregnancy rate was greater (P = 0.02) in BCS 6 cows. No differences (P = 0.48 to 0.83) were detected in calf birth weight or ADG because of BCS at parturition. Dietary lipid supplementation did not influence (P = 0.23 to 0.96) cow BW change, BCS change, 12th rib fat, LM area, milk yield, milk energy, milk fat percentage, milk lactose percentage, first service conception, overall pregnancy rates, or calf performance. Although cows in BCS of 4 at parturition seemed capable of maintaining BCS during lactation, the overall decrease in pregnancy rate indicates cows should be managed to achieve a BCS >4 before parturition to improve reproductive success.

  11. M-Theory and Maximally Supersymmetric Gauge Theories

    CERN Document Server

    Lambert, Neil

    2012-01-01

    In this informal review for non-specalists we discuss the construction of maximally supersymmetric gauge theories that arise on the worldvolumes branes in String Theory and M-Theory. Particular focus is made on the relatively recent construction of M2-brane worldvolume theories. In a formal sense, the existence of these quantum field theories can be viewed as predictions of M-Theory. Their construction is therefore a reinforcement of the ideas underlying String Theory and M-Theory. We also briefly discuss the six-dimensional conformal field theory that is expected to arise on M5-branes. The construction of this theory is not only an important open problem for M-Theory but also a significant challenge to our current understanding of quantum field theory more generally.

  12. Ad libitum Pasture Feeding in Late Pregnancy Does Not Improve the Performance of Twin-bearing Ewes and Their Lambs.

    Science.gov (United States)

    Corner-Thomas, R A; Back, P J; Kenyon, P R; Hickson, R E; Ridler, A L; Stafford, K J; Morris, S T

    2015-03-01

    The present study evaluated the effect of controlled ryegrass-white clover herbage availability from day 128 until day 142 of pregnancy in comparison to unrestricted availability, on the performance of twin-bearing ewes of varying body condition score (BCS; 2.0, 2.5, or 3.0) and their lambs. It was hypothesised that under conditions of controlled herbage availability, the performance of lambs born to ewes with a greater BCS would be greater than those born to ewes with a lower BCS. During the period that the nutritional regimens were imposed, the pre- and post-grazing herbage masses of the Control regimen (1,070±69 and 801±30 kg dry matter [DM]/ha) were lower than the ad libitum regimen (1,784±69 and 1,333±33 kg DM/ha; pewe live weight, BCS and back fat depth or on lamb live weight, indices of colostrum uptake, maximal heat production, total litter weight weaned or survival to weaning (p>0.05). The difference in ewe BCSs and back fats observed among body condition groups was maintained throughout pregnancy (pewes from the BCS2.0 group had lower BCS and live weight (2.4±0.2, 74.3±2.6 kg) than both the BCS2.5 (2.6±0.2, 78.6±2.4 kg) and BCS3.0 ewes (2.7±0.2, 79.0±2.6 kg; p0.05). Ewe BCS group had no effect on lamb live weight at birth or weaning or on maximal heat production (p>0.05). Serum gamma glutamyl transferase concentrations of lambs born to BCS3.0 ewes were higher within 36 hours of birth than lambs born to BCS2.0 ewes and BCS2.5 ewes (51.8±1.9 vs 46.5±1.9 and 45.6±1.9 IU/mL, respectively [pewe body condition on lamb plasma glucose concentration (p>0.05). Lamb survival was the only lamb parameter that showed an interaction between ewe nutritional regimen and ewe BCS whereby survival of lambs born to BCS2.5 and BCS3.0 ewes differed but only within the Control nutritional regimen ewes (pewes with pre- and post-grazing ryegrass-white clover herbage covers of approximately 1,100 and 800 kg DM/ha in late pregnancy, provided that herbage covers are 1400

  13. Measurement of the magnetic penetration depth in p-doped superconducting diamond films

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, Lorenz; Brunner, Markus C.P.; Schneider, Ina; Kronfeldner, Klaus [University of Regensburg (Germany); Bousquet, Jessica; Bustarret, Etienne; Strunk, Christoph [Institut Neel, Grenoble (France)

    2016-07-01

    Boron-doped diamond becomes superconducting once a critical doping concentration of 4.5 x 10{sup 20} cm{sup -3} is reached. Mutual inductance measurements with a two-coil setup have been performed to determine the magnetic penetration depth λ(T), which is a measure for the superfluid stiffnes θ ∝ 1/λ{sup 2}(T). Two superconducting p-doped diamond films with thicknesses of 145 nm and 345 nm were investigated. At low temperatures these values agree reasonably with the values expected within BCS-theory using T{sub c}, carrier density and mean free path determined from electric transport measurements. Magnetic penetration depths of 3.7 μm for the thinner and 2.6 μm for the thicker film have been found. λ decreases and accordingly θ increases with increasing film thickness. On the other hand, the superfluid stiffness drops by a factor of 2 or even more at T{sub c}/2, i.e., much faster than expected from BCS-theory, but remains finite between T{sub c}/2 < T < T{sub c}. At present it is unclear, whether this behavior results from the proliferation of phase fluctuations already far below T{sub c} or from a spatial inhomogeneity of the films.

  14. Intrinsic Paramagnetic Meissner Effect Due to s-Wave Odd-Frequency Superconductivity

    Directory of Open Access Journals (Sweden)

    A. Di Bernardo

    2015-11-01

    Full Text Available In 1933, Meissner and Ochsenfeld reported the expulsion of magnetic flux—the diamagnetic Meissner effect—from the interior of superconducting lead. This discovery was crucial in formulating the Bardeen-Cooper-Schrieffer (BCS theory of superconductivity. In exotic superconducting systems BCS theory does not strictly apply. A classical example is a superconductor-magnet hybrid system where magnetic ordering breaks time-reversal symmetry of the superconducting condensate and results in the stabilization of an odd-frequency superconducting state. It has been predicted that under appropriate conditions, odd-frequency superconductivity should manifest in the Meissner state as fluctuations in the sign of the magnetic susceptibility, meaning that the superconductivity can either repel (diamagnetic or attract (paramagnetic external magnetic flux. Here, we report local probe measurements of faint magnetic fields in a Au/Ho/Nb trilayer system using low-energy muons, where antiferromagnetic Ho (4.5 nm breaks time-reversal symmetry of the proximity-induced pair correlations in Au. From depth-resolved measurements below the superconducting transition of Nb, we observe a local enhancement of the magnetic field in Au that exceeds the externally applied field, thus proving the existence of an intrinsic paramagnetic Meissner effect arising from an odd-frequency superconducting state.

  15. Evaluation and optimized selection of supersaturating drug delivery systems of posaconazole (BCS class 2b) in the gastrointestinal simulator (GIS): An in vitro-in silico-in vivo approach.

    Science.gov (United States)

    Hens, Bart; Bermejo, Marival; Tsume, Yasuhiro; Gonzalez-Alvarez, Isabel; Ruan, Hao; Matsui, Kazuki; Amidon, Gregory E; Cavanagh, Katie L; Kuminek, Gislaine; Benninghoff, Gail; Fan, Jianghong; Rodríguez-Hornedo, Naír; Amidon, Gordon L

    2018-03-30

    Supersaturating drug delivery systems (SDDS) have been put forward in the recent decades in order to circumvent the issue of low aqueous solubility. Prior to the start of clinical trials, these enabling formulations should be adequately explored in in vitro/in silico studies in order to understand their in vivo performance and to select the most appropriate and effective formulation in terms of oral bioavailability and therapeutic outcome. The purpose of this work was to evaluate the in vivo performance of four different oral formulations of posaconazole (categorized as a biopharmaceutics classification system (BCS) class 2b compound) based on the in vitro concentrations in the gastrointestinal simulator (GIS), coupled with an in silico pharmacokinetic model to predict their systemic profiles. Recently published intraluminal and systemic concentrations of posaconazole for these formulations served as a reference to validate the in vitro and in silico results. Additionally, the morphology of the formed precipitate of posaconazole was visualized and characterized by optical microscopy studies and thermal analysis. This multidisciplinary work demonstrates an in vitro-in silico-in vivo approach that provides a scientific basis for screening SDDS by a user-friendly formulation predictive dissolution (fPD) device in order to rank these formulations towards their in vivo performance. Copyright © 2018. Published by Elsevier B.V.

  16. Some signatures of quantum chaos on dirty superconductors

    International Nuclear Information System (INIS)

    Zhou, F

    2001-01-01

    The Anderson theory of dirty superconductivity was established a few years after the discovery of the BCS wave function. Disregarding the rich properties in the one-particle energy spectrum in dirty limit, the theory claimed that the ground state condensate is translationally invariant and free from Toulouse type of frustrations. This theory also set down the foundation of dirty superconductivity in the presence of external fields. In this talk, I demonstrate the failure of the Anderson theory in amorphous superconducting films in general and its connection with Wigner-Dyson surmise. I will discuss the Chandrasekar-Glogston limit in which the nodes in one-particle wave functions are shown to result in a novel superconducting glass phase. I will also discuss why nature has tolerated the failure. (4. mesoscopic superconductivity)

  17. Breast cancer survivors' perceived medical communication competence and satisfaction with care at the end of treatment.

    Science.gov (United States)

    Brédart, Anne; Kop, Jean-Luc; Fiszer, Chavie; Sigal-Zafrani, Brigitte; Dolbeault, Sylvie

    2015-12-01

    Information is a care priority in most breast cancer survivors (BCS). We assessed whether BCS information needs at 8 months after hospital cancer treatment could be related to their age, education level, perceived medical communication competence, satisfaction with care, attachment style, and self-esteem. Of 426 BCS approached during the last week of treatment (T1), 85% completed the Medical Communication Competence Scale, European Organisation for Research and Treatment of Cancer Satisfaction with Care Questionnaire, Rosenberg's Self-Esteem Scale and Experiences in Close Relationships Scale. The Hospital Anxiety and Depression Scale and the Supportive Care Needs Survey were completed at T1 and again 8 months later (T2) with a 66% (n = 283) response rate. Baseline respondents' median (range) age was 56 years (23-86 years). Information needs decreased over time, although some persisted. Multivariate regression analyses evidenced overall higher information needs at T2 in younger BCS and in those dissatisfied with the information provided at T1. Specifically, in younger BCS, higher information needs were related to lower satisfaction with doctors' availability, and in older BCS, they were related to higher self-perceived competence in information giving, lower self-perceived competence in information seeking, and lower satisfaction with doctors' information provision. Psychological distress was strongly related to information needs. Education, BCS attachment style, and self-esteem were not associated with information needs. In order to enhance supportive care for BCS, younger BCS should be provided with more time to address all their concerns and older BCS should be encouraged to express their specific desires for information. Copyright © 2015 John Wiley & Sons, Ltd.

  18. Sound waves and dynamics of superfluid Fermi gases in optical lattices

    International Nuclear Information System (INIS)

    Zhang Aixia; Xue Jukui

    2009-01-01

    The sound waves, the stability of Bloch waves, the Bloch oscillation, and the self-trapping phenomenon in interacting two-component Fermi gases throughout the BEC-BCS crossover in one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) optical lattices are discussed in detail. Within the hydrodynamical theory and by using the perturbative and tight-binding approximation, sound speed in both weak and tight 1D, 2D, 3D optical lattices, and the criteria for occurrences of instability of Bloch waves and self-trapping of Fermi gases along the whole BEC-BCS crossover in tight 1D, 2D, 3D optical lattices are obtained analytically. The results show that the sound speed, the criteria for occurrences of instability of Bloch waves and self-trapping, and the destruction of Bloch oscillation are modified dramatically by the lattice parameters (lattice dimension and lattice strength), the atom density or atom number, and the atom interaction.

  19. Signature of magnetic-dependent gapless odd frequency states at superconductor / ferromagnet interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, Jason [Department of Materials Science, 27 Charles Babbage Road, Cambridge, CB30FS (United Kingdom)

    2015-07-01

    The theory of superconductivity developed by Bardeen, Cooper, and Schrieffer (BCS) explains the stabilisation of electron pairs into a spin-singlet, even frequency, state by the formation of an energy gap below which the density of states (DoS) is zero. At a superconductor interface with an inhomogeneous ferromagnet, a gapless odd frequency superconducting state is predicted in which the Cooper pairs are in a spin-triplet state. Although indirect evidence for such a state has been obtained, the gap structure and pairing symmetry have not so far been determined. In this talk I will present scanning tunnelling spectroscopy of Nb superconducting films proximity coupled to epitaxial Ho. These measurements reveal pronounced changes to the Nb sub-gap superconducting DoS on driving the Ho through a metamagnetic transition from a helical antiferromagnetic to a homogeneous ferromagnetic state for which a BCS-like gap is recovered. The results verify odd frequency spin-triplet superconductivity at superconductor / inhomogeneous magnet interfaces.

  20. Sound propagation in elongated superfluid fermionic clouds

    International Nuclear Information System (INIS)

    Capuzzi, P.; Vignolo, P.; Federici, F.; Tosi, M. P.

    2006-01-01

    We use hydrodynamic equations to study sound propagation in a superfluid Fermi gas at zero temperature inside a strongly elongated cigar-shaped trap, with main attention to the transition from the BCS to the unitary regime. First, we treat the role of the radial density profile in the limit of a cylindrical geometry and then evaluate numerically the effect of the axial confinement in a configuration in which a hole is present in the gas density at the center of the trap. We find that in a strongly elongated trap the speed of sound in both the BCS and the unitary regime differs by a factor √(3/5) from that in a homogeneous three-dimensional superfluid. The predictions of the theory could be tested by measurements of sound-wave propagation in a setup such as that exploited by Andrews et al. [Phys. Rev. Lett. 79, 553 (1997)] for an atomic Bose-Einstein condensate

  1. Plasmon-phonon pairing mechanism and superconducting state parameters in layered mercury cuprates

    International Nuclear Information System (INIS)

    Varshney, D.; Tosi, M.P.

    1999-06-01

    An effective two-dimensional dynamic interaction is developed which incorporated screening of holes by plasmons and by optical phonons to discuss the nature of the pairing mechanism leading to superconductivity in layered mercury cuprates. The system is treated as an ionic solid containing layers of charge carriers and a model dielectric function is set up which fulfils the appropriate sum rules on the electronic and ionic polarizabilities. The values of the coupling strength and of the Coulomb interaction parameter indicate that the superconductor is in the strong coupling regime with effective screening of the charge carriers. The superconducting transition temperature of optically doped HgBa 2 CuO 4+δ is estimated as 94 K from Kresin's strong coupling theory and the energy gap ratio is substantially larger than the BCS value. The value of the isotope exponent is severely reduced below the BCS value. The implications of the model and its analysis are discussed. (author)

  2. Excitonic condensation for the surface states of topological insulator bilayers

    International Nuclear Information System (INIS)

    Wang Zhigang; Fu Zhenguo; Zhang Ping; Hao Ningning

    2012-01-01

    We propose a generic topological insulator bilayer (TIB) system to study the excitonic condensation with self-consistent mean-field (SCMF) theory. We show that the TIB system presents the crossover behavior from the Bardeen-Cooper-Schrieffer (BCS) limit to the Bose-Einstein condensation (BEC) limit. Moreover, in comparison with traditional semiconductor systems, we find that for the present system the superfluid property in the BEC phase is more sensitive to electron-hole density imbalance and the BCS phase is more robust. Applying this TIB model to the Bi 2 Se 3 -family material, we find that the BEC phase is most likely to be observed in experiment. We also calculate the critical temperature for the Bi 2 Se 3 -family TIB system, which is ∼100 K. More interestingly, one can expect this relative high-temperature excitonic condensation, since our calculated SCMF critical temperature is approximately equal to the Kosterlitz-Thouless transition temperature. (paper)

  3. Exotic superconductivity with enhanced energy scales in materials with three band crossings

    Science.gov (United States)

    Lin, Yu-Ping; Nandkishore, Rahul M.

    2018-04-01

    Three band crossings can arise in three-dimensional quantum materials with certain space group symmetries. The low energy Hamiltonian supports spin one fermions and a flat band. We study the pairing problem in this setting. We write down a minimal BCS Hamiltonian and decompose it into spin-orbit coupled irreducible pairing channels. We then solve the resulting gap equations in channels with zero total angular momentum. We find that in the s-wave spin singlet channel (and also in an unusual d-wave `spin quintet' channel), superconductivity is enormously enhanced, with a possibility for the critical temperature to be linear in interaction strength. Meanwhile, in the p-wave spin triplet channel, the superconductivity exhibits features of conventional BCS theory due to the absence of flat band pairing. Three band crossings thus represent an exciting new platform for realizing exotic superconducting states with enhanced energy scales. We also discuss the effects of doping, nonzero temperature, and of retaining additional terms in the k .p expansion of the Hamiltonian.

  4. Far from the intermediate nuclear field

    International Nuclear Information System (INIS)

    Dietrich, K.; Wagner, G.J.; Gregoire, C.; Campi, X.; Silvestre-Brac, B.; Platchkov, S.; Mayer, B.; Abgrall, Y.; Bohigas, O.; Grange, P.; Signarbieux, C.

    1988-01-01

    Pairing correlations in nuclear physics; the BCS state and quasi-particles; the layer model; collision effects on nuclear dynamics; the theory of cluster formation (application to nucleus fragmentation); short range correlations (few-particle systems); deuterium electron scattering; dibaryonic resonances; traditional and exotic hadron probes of nuclear structure; spectral fluctuations and chaotic motion; corrections to the intermediate nuclear field (nonrelativistic and other effects); and heavy nuclei splitting and nuclear superfluidity are introduced [fr

  5. Transfer Behavior of the Weakly Acidic BCS Class II Drug Valsartan from the Stomach to the Small Intestine During Fasted and Fed States.

    Science.gov (United States)

    Hamed, Rania; Alnadi, Sabreen Hasan

    2018-05-07

    The objective of this study was to investigate the transfer behavior of the weakly acidic BCS class II drug valsartan from the stomach to the small intestine during fasted and fed states. An in vitro transfer model previously introduced by Kostewicz et al. (J Pharm Pharmacol 56(1):43-51, 2004) based on a syringe pump and a USP paddle apparatus was used to determine the concentration profiles of valsartan in the small intestine. Donor phases of simulated gastric fluid during fasted (FaSSGF) and fed (FeSSGF) states were used to predisperse Diovan® tablets (160 mg valsartan). The initial concentrations of valsartan in FaSSGF and FeSSGF were 6.2 and 91.8%, respectively. Valsartan dispersions were then transferred to acceptor phases that simulate intestinal fluid and cover the physiological properties (pH, buffer capacity, and ionic strength) of the gastrointestinal fluid at a flow rate of 2 mL/min. The pH measurements were reported at time intervals corresponded to those of the transfer experiments to investigate the effect of percent dissolved of valsartan in the donor phase on lowering the pH of the acceptor phases. The f2 similarity test was used to compare the concentration profiles in the acceptor phases. In fasted state, the concentration of valsartan in the acceptor phases ranged between 33.1 and 89.4% after 240 min. Whereas in fed state, valsartan was fully dissolved in all acceptor phases within a range of 94.5-104.9% after 240 min. Therefore, the transfer model provides a useful screen for the concentrations of valsartan in the small intestine during fasted and fed states.

  6. Towards a theory of spacetime theories

    CERN Document Server

    Schiemann, Gregor; Scholz, Erhard

    2017-01-01

    This contributed volume is the result of a July 2010 workshop at the University of Wuppertal Interdisciplinary Centre for Science and Technology Studies which brought together world-wide experts from physics, philosophy and history, in order to address a set of questions first posed in the 1950s: How do we compare spacetime theories? How do we judge, objectively, which is the “best” theory? Is there even a unique answer to this question? The goal of the workshop, and of this book, is to contribute to the development of a meta-theory of spacetime theories. Such a meta-theory would reveal insights about specific spacetime theories by distilling their essential similarities and differences, deliver a framework for a class of theories that could be helpful as a blueprint to build other meta-theories, and provide a higher level viewpoint for judging which theory most accurately describes nature. But rather than drawing a map in broad strokes, the focus is on particularly rich regions in the “space of spaceti...

  7. Effects of precalving body condition score and prepartum feeding level on production, reproduction, and health parameters in pasture-based transition dairy cows.

    Science.gov (United States)

    Roche, J R; Meier, S; Heiser, A; Mitchell, M D; Walker, C G; Crookenden, M A; Riboni, M Vailati; Loor, J J; Kay, J K

    2015-10-01

    Precalving feeding level alters postcalving energy balance, dry matter intake, the liver and adipose tissue transcriptome, hepatic lipidosis, and the risk of metabolic diseases in both high-production cows consuming total mixed rations and moderate-production cows grazing pasture. We hypothesized that the reported benefits of a controlled restriction before calving are dependent on precalving body condition score (BCS): low BCS animals would not benefit from reduced feeding levels precalving, but high BCS cows would have metabolic and immunomodulatory profiles indicative of an improved health status. One hundred sixty-one days before calving, 150 cows were allocated randomly to 1 of 6 treatment groups (n = 25) in a 2 × 3 factorial arrangement: 2 precalving BCS categories (4.0 and 5.0; based on a 10-point scale: BCS4 and BCS5, respectively) and 3 levels of energy intake during the 3 wk preceding calving (75, 100, and 125% of estimated requirements). Cows in the BCS4 and BCS5 groups were managed through late lactation to ensure that target calving BCS was achieved at dry off. Cows were then fed to maintain this BCS target until 3 wk before expected calving date, at which point they were managed within their allotted precalving energy intake treatments by offering different allowances of fresh pasture/cow per day. Milk production, body weight, and BCS were measured weekly; blood was sampled weekly before and after calving and on d 0, 1, 2, 3, and 4 relative to calving. Aspirated plasma was assayed for nonesterified fatty acids, β-hydroxybutyrate, total protein, albumin, cholesterol, haptoglobin, IL-1β, IL-6, total antioxidant capacity, and reactive oxygen species. Liver was sampled wk 1, 2, and 4 postcalving for triacylglycerol analysis. Results confirm that precalving BCS and precalving feeding level have both independent and interdependent effects on production and health characteristics of transition dairy cows. Irrespective of precalving BCS, a controlled

  8. Factors that influence awareness of breast cancer screening among Arab women in Qatar: results from a cross sectional survey.

    Science.gov (United States)

    Donnelly, Tam Truong; Khater, Al-Hareth Al; Al-Bader, Salha Bujassoum; Al Kuwari, Mohammed Ghaith; Malik, Mariam; Al-Meer, Nabila; Singh, Rajvir; Fung, Tak

    2014-01-01

    Breast cancer is the most common cancer among women in the State of Qatar. Due to low participation in breast cancer screening (BCS) activities, women in Qatar are often diagnosed with breast cancer at advanced stages of the disease. Findings indicate that low participation rates in BCS activities are significantly related to women's low level of awareness of breast cancer screening. The objectives of this study were to: (1) determine the factors that influence Qatari women's awareness of breast cancer and its screening activities: and (2) to find ways to effectively promote breast cancer screening activities among Arabic speaking women in Qatar. A multicenter, cross-sectional quantitative survey of 1,063 (87.5% response rate) female Qatari citizens and non-Qatari Arabic-speaking residents, 35 years of age or older, was conducted in Qatar from March 2011 to July 2011. Outcome measures included participant awareness levels of the most recent national recommended guidelines of BCS, participation rates in BCS activities, and factors related to awareness of BCS activities. While most participants (90.7%) were aware of breast cancer, less than half had awareness of BCS practices (28.9% were aware of breast self-examination and 41.8% of clinical breast exams, while 26.4% knew that mammography was recommended by national screening guidelines. Only 7.6% had knowledge of all three BCS activities). Regarding BCS practice, less than one-third practiced BCS appropriately (13.9% of participants performed breast self-examination (BSE) monthly, 31.3% had a clinical breast exam (CBE) once a year or once every two years, and 26.9% of women 40 years of age or older had a mammogram once every year or two years). Awareness of BCS was significantly related to BCS practice, education level, and receipt of information about breast cancer and/or BCS from a variety of sources, particularly doctors and the media. The low levels of participation rates in BCS among Arab women in this study

  9. Pre-conception energy balance and secondary sex ratio--partial support for the Trivers-Willard hypothesis in dairy cows.

    Science.gov (United States)

    Roche, J R; Lee, J M; Berry, D P

    2006-06-01

    According to the Trivers-Willard hypothesis, maternal condition at or around conception affects the secondary sex ratio in mammals. However, there are little or no data available on indicators of maternal condition in dairy cows on the sex of the resultant offspring. A total of 76,607 body condition score (BCS; scale of 1 to 5) records and 76,611 body weight (BW) records from 3,209 lactations across 1,172 cows were extracted from a research database collated from one research herd between 1986 and 2004, inclusive. Exclusion of multiple births and cows with no information before calving (e.g., nulliparous animals) resulted in 2,029 records with BCS and BW observations from the previous calving, and 2,002 and 1,872 lactations with BCS and BW observations at conception and midgestation, respectively. Change in BCS and BW between calving and conception and between conception and midgestation was calculated per lactation. Generalized estimating equations were used to model the logit of the probability of a male calf, in which cow was included as a repeated effect with a first-order autoregressive correlation structure assumed among records within cow. Of the BCS variables investigated, there was a linear relationship between the logit of the probability of a male calf and BCS change between calving and conception, the rate of BCS change over this period (BCS divided by days in milk), and BCS at the calving event immediately before conception. The birth of a bull calf was 1.85 times more likely in cows that lost no BCS from calving to conception compared with cows that lost one BCS unit from calving to conception. This increase in odds was equivalent to a 14% unit increase in the probability of a male calf (from 54 to 68%). The amount of BW lost between calving and conception and the rate of loss affected the sex of the resultant offspring. Less BW loss or greater BW gain between calving and conception was associated with greater likelihood of a male calf. Results

  10. Biowaiver monographs for immediate release solid oral dosage forms: acetaminophen (paracetamol).

    NARCIS (Netherlands)

    Kalantzi, L; Reppas, C; Dressman, J B; Amidon, G L; Junginger, H E; Midha, K K; Shah, V P; Stavchansky, S A; Barends, Dirk M

    2006-01-01

    Literature data are reviewed on the properties of acetaminophen (paracetamol) related to the biopharmaceutics classification system (BCS). According to the current BCS criteria, acetaminophen is BCS Class III compound. Differences in composition seldom, if ever, have an effect on the extent of

  11. Preliminary analysis of modified low density lipoproteins in the serum of healthy and obese dogs and cats

    Directory of Open Access Journals (Sweden)

    Nobuko eMori

    2015-09-01

    Full Text Available Oxidized low-density lipoprotein (LDL is thought to play an important role in the inflammatory response associated with human obesity. The purpose of this preliminary study was to determine oxidized LDL concentrations in healthy dogs and cats, and to evaluate whether obesity affects oxidized LDL concentration, using 39 cats and 19 dogs that had visited 2 different veterinary clinics in Japan. We hypothesized that oxidized LDL concentrations measured against body condition score (BCS may have a potential value in evaluating the qualities of accumulated or circulating lipids in obese dogs and cats that do not show signs of metabolic diseases. The mean oxidized LDL value in BCS3 dogs (2.4 ± 0.9 μg/dl was very similar to that of BCS5 dogs (2.2 ± 0.3 μg/dl. The mean oxidized LDL value of BCS4 dogs was 7.2 ± 10.3 μg/dl and the highest among three groups. BCS4 dogs included two dogs whose oxidized LDL values were higher than the mean oxidized LDL value of healthy humans (11.2 ± 0.3 μg/dl. On the other hand, the mean oxidized LDL value of BCS3 cats was 2.5 ± 0.9 μg/dl, and those of BCS4 and 5 cats were higher than that of BCS3, but there was no significant difference. The BCS4 cat group included one cat with a higher oxidized LDL value, and the BCS5 group also included two cats with oxidized LDL values higher than the mean oxidized LDL value of healthy humans. Interestingly, the oxidized LDL values in 2 obese dogs and 3 obese cats were indeed higher than the mean oxidized LDL value of humans with coronary artery disease (20.1 ± 1.1 μg/dl. In conclusion, this preliminary study showed reference ranges of oxidized dogs and cats against BCS. Obesity alone does not appear to have any direct effect on serum oxidized LDL values in healthy dogs and cats.

  12. Dependence theory via game theory

    NARCIS (Netherlands)

    Grossi, D.; Turrini, P.

    2011-01-01

    In the multi-agent systems community, dependence theory and game theory are often presented as two alternative perspectives on the analysis of social interaction. Up till now no research has been done relating these two approaches. The unification presented provides dependence theory with the sort

  13. Associations among body condition score, body weight, and reproductive performance in seasonal-calving dairy cattle.

    Science.gov (United States)

    Roche, J R; Macdonald, K A; Burke, C R; Lee, J M; Berry, D P

    2007-01-01

    The objective of the present study was to identify and quantify relationships between body condition score (BCS) and body weight (BW) in dairy cows with reproduction variables in pasture-based, seasonal-calving dairy herds. Over 2,500 lactation records from 897 spring-calving Holstein-Friesian dairy cows were used in the analyses. Eleven BCS- and 11 BW-related variables were generated, including observations at calving, nadir, planned start of mating (PSM), and first service, as well as days to nadir and the amount and rate of change between periods. The binary reproductive variables were cycling by PSM, mated in the first 21 d from PSM, pregnant to first service, and pregnant in the first 21, 42, and 84 d of the seasonal mating period. Generalized estimating equations were used to identify BCS and BW variables that significantly affected the probability of a successful reproductive outcome. After adjusting for the fixed effect of year of calving, parity (for cycling by PSM only), and the interval from calving to either first service or PSM, reproductive performance was found to be significantly affected by BW or BCS at key points, and by BCS and BW change during lactation. All reproductive response measures were negatively affected when BCS and BW measures indicated an increased severity and duration of the postpartum negative energy balance. In particular, cycling by PSM was positively associated with calving BCS, whereas pregnancy at 21, 42, and 84 d post-PSM were positively associated with nadir BCS and BW gain post-PSM, and negatively associated with BCS loss between calving and nadir. The results highlight the important role that BCS and BW loss has on reproductive performance, especially in seasonal-calving dairy systems because of the short period between calving and PSM.

  14. Rationality, Theory Acceptance and Decision Theory

    Directory of Open Access Journals (Sweden)

    J. Nicolas Kaufmann

    1998-06-01

    Full Text Available Following Kuhn's main thesis according to which theory revision and acceptance is always paradigm relative, I propose to outline some possible consequences of such a view. First, asking the question in what sense Bayesian decision theory could serve as the appropriate (normative theory of rationality examined from the point of view of the epistemology of theory acceptance, I argue that Bayesianism leads to a narrow conception of theory acceptance. Second, regarding the different types of theory revision, i.e. expansion, contraction, replacement and residuals shifts, I extract from Kuhn's view a series of indications showing that theory replacement cannot be rationalized within the framework of Bayesian decision theory, not even within a more sophisticated version of that model. Third, and finally, I will point to the need for a more comprehensive model of rationality than the Bayesian expected utility maximization model, the need for a model which could better deal with the different aspects of theory replacement. I will show that Kuhn's distinction between normal and revolutionary science gives us several hints for a more adequate theory of rationality in science. I will also show that Kuhn is not in a position to fully articulate his main ideas and that he well be confronted with a serious problem concerning collective choice of a paradigm.

  15. Hepatic Scintigraphic Findings of Budd-Chiari Syndrome due to Inferior Vena Caval Obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Hoon; Chung, Soo Kyo; Byun, Jae Young; Lee, Sung Yong; Shinn, Kyung Sub; Kim, Choon Yul; Bahk, Yong Whee [Catholic University College of Medicine, Seoul (Korea, Republic of)

    1988-03-15

    Budd-Chiari syndrome (BCS) is a rare clinical entity characterized by post-sinusoidal portal hypertension caused by the obstruction to the hepatic vein outflow. The diagnosis is suggested by hepatic scintigraphy and is usually confirmed by hepatic venography, inferior vena cavography and biopsy. The scintigraphic finding of BCS caused by the obstruction of main hepatic vein has been reported to consist typically of hypertrophy of the caudate lobe with increased radionuclide accumulation. Such a typical finding has been accounted for by the fact that the venous outflow from the caudate lobe is preserved when the main hepatic vein is obstructed. But usually, the hepatic venous outflow from the caudate lobe is also obstructed in BCS due to inferior vena caval obstruction. So hepatic scintigraphic findings of BCS due to inferior vena caval obstruction show different findings as compared with the BCS due to hepatic vein obstruction. We evaluate the hepatic scintigrams of the 13 cases of BCS due to inferior vena caval obstruction and review the literatures. The results are as follows: 1) We cannot observe the caudate lobe hypertrophy with increased uptake, which is known as a classic finding in BCS due to hepatic vein obstruction. 2) The most prominent hepatic scintigraphic findings of BCS are nonhomogenous uptake in the liver with extrahepatic uptake in the all cases. 3) We can see cold areas at the superior aspect of right hepatic lobe in 7 cases (54%). This is a useful finding suggesting BCS due to inferior vena caval obstruction.

  16. Patients with invasive lobular breast cancer are less likely to undergo breast-conserving surgery: a population based study in the Netherlands.

    Science.gov (United States)

    Truin, W; Roumen, R M; Siesling, S; van der Heiden-van der Loo, M; Duijm, L E M; Tjan-Heijnen, V C G; Voogd, A C

    2015-05-01

    The aim of this study was to compare the frequency of breast-conserving surgery (BCS) between early-stage invasive ductal (IDC) and invasive lobular breast cancer (ILC). Women with primary non-metastatic pT1 and pT2 IDC or ILC diagnosed between 1990 and 2010 were selected from the NCR. All patients underwent BCS or primary mastectomy without neoadjuvant treatment and proportions per year were calculated. Logistic regression analysis with adjustment for period, age, nodal status and tumor size was performed to determine the impact of histology on the likelihood of undergoing BCS. A total of 152,574 patients underwent surgery in the period between 1990 and 2010, of which 89 % had IDC and 11 % had ILC. In the group of IDC with pT1 and pT2 tumors combined, 54 % underwent BCS compared with 43 % of patients with ILC (p < 0.0001). The proportion of patients with IDC treated by BCS increased from 46 % in 1990 to 62 % in 2010. The BCS rate among ILC patients increased from 39 % in 1990 to 48 % in 2010. Patients with ILC were less likely to undergo BCS compared with patients with IDC (odds ratio 0.69; 95 % confidence interval 0.66-0.71). The incidence of BCS for patients with IDC or ILC is rising in The Netherlands. However, the increase of BCS is less explicit in patients with ILC, with a higher chance of undergoing mastectomy compared with patients with IDC.

  17. Body condition scores at calving and their association with dairy cow performance and health in semiarid environment under two cooling systems

    Directory of Open Access Journals (Sweden)

    Mohamed A.B. Mandour

    2015-02-01

    Full Text Available Under tropical environments cow’s body condition at calving may influence productivity and health performance. Therefore, the current research evaluated the impact of body condition score (BCS at calving on milk production traits and health problems of primiparous and multiparous cows raised under two cooling systems in semi-arid environment. Milk yield parameters and health disorders data at different parities were obtained from 1700 Holstein cows, which were managed under Korral Kool (KKC and fan (FC cooling systems in Saudi Arabia. The results revealed that KKC system induced high level of milk production improvement (305TM, days in milk, daily milk yield (P<0.05 compared to FC, especially in multiparous cows. There was an advantage of the high BCS group under KKC system over the FC system for peak yield and period. Cows from both cooling systems having moderate BCS outdid the other groups for total milk yield. Low BCS primiparous cows reared under KKC system were the most to suffer from stillbirth (18%, and calving ease (26.1% in winter, while high BCS were the most to be treated for mastitis (8.5% in summer. On the other hand, spring calved multiparous cows raised under FC system suffered more from lameness (21.57% - high BCS and milk fever (4.4% - moderate BCS. Further, cows having moderate BCS kept under KKC system had the highest incidence of lameness (62.2%, and abomasum displacement (4.4%. In conclusion, achieving correct BCS at calving and cooling system is important to avoid calving subsequent lactation performance and metabolic disease losses.

  18. Hepatic Scintigraphic Findings of Budd-Chiari Syndrome due to Inferior Vena Caval Obstruction

    International Nuclear Information System (INIS)

    Kim, Sung Hoon; Chung, Soo Kyo; Byun, Jae Young; Lee, Sung Yong; Shinn, Kyung Sub; Kim, Choon Yul; Bahk, Yong Whee

    1988-01-01

    Budd-Chiari syndrome (BCS) is a rare clinical entity characterized by post-sinusoidal portal hypertension caused by the obstruction to the hepatic vein outflow. The diagnosis is suggested by hepatic scintigraphy and is usually confirmed by hepatic venography, inferior vena cavography and biopsy. The scintigraphic finding of BCS caused by the obstruction of main hepatic vein has been reported to consist typically of hypertrophy of the caudate lobe with increased radionuclide accumulation. Such a typical finding has been accounted for by the fact that the venous outflow from the caudate lobe is preserved when the main hepatic vein is obstructed. But usually, the hepatic venous outflow from the caudate lobe is also obstructed in BCS due to inferior vena caval obstruction. So hepatic scintigraphic findings of BCS due to inferior vena caval obstruction show different findings as compared with the BCS due to hepatic vein obstruction. We evaluate the hepatic scintigrams of the 13 cases of BCS due to inferior vena caval obstruction and review the literatures. The results are as follows: 1) We cannot observe the caudate lobe hypertrophy with increased uptake, which is known as a classic finding in BCS due to hepatic vein obstruction. 2) The most prominent hepatic scintigraphic findings of BCS are nonhomogenous uptake in the liver with extrahepatic uptake in the all cases. 3) We can see cold areas at the superior aspect of right hepatic lobe in 7 cases (54%). This is a useful finding suggesting BCS due to inferior vena caval obstruction.

  19. Thrombophilic Genetic Factors PAI-1, MTHFRC677T, V Leiden 506Q, and Prothrombin 20210A in Noncirrhotic Portal Vein Thrombosis and Budd-Chiari Syndrome in a Caucasian Population

    Directory of Open Access Journals (Sweden)

    Mario D’Amico

    2013-01-01

    Full Text Available Thrombophilic genetic factors PAI-1, MTHFRC677T, V Leiden 506Q, and Prothrombin 20210A were studied as risk factors in 235 Caucasian subjects: 85 patients with abdominal thrombosis (54 with portal vein thrombosis (PVT and 31 with Budd-Chiari syndrome (BCS without liver cirrhosis or hepatocellular carcinoma and 150 blood bank donors. Seventy-five patients with PVT/BCS showed associated disease or particular clinical status (46 PVT/29 BCS: 37 myeloproliferative neoplasm (20 PVT/17 BCS, 12 abdominal surgery (10 PVT/2 BCS, 10 contraception or pregnancy (6 PVT/4 BCS, 7 abdominal acute disease (6 PVT/1 BCS, and 9 chronic disease (4 PVT/5 BCS; ten patients did not present any association (8 PVT/2 BCS. PAI-14G-4G, MTHFR677TT, and V Leiden 506Q were significantly frequent (OR 95% CI and χ2 test with P value in abdominal thrombosis; in these patients PAI-14G-4G and MTHFR677TT distributions deviated from that expected from a population in the Hardy-Weinberg equilibrium (PAI-1: χ2=13.8, P<0.001; MTHFR677: χ2=7.1, P<0.01, whereas the equilibrium was respected in healthy controls. V Leiden Q506 and Prothrombin 20210A were in the Hardy-Weinberg equilibrium both in patients with abdominal thrombosis and healthy controls. Our study shows an important role of PAI-14G-4G and MTHFR677TT in abdominal thrombosis without liver cirrhosis or hepatocellular carcinoma.

  20. Genetic parameters for body condition score, body weight, milk yield, and fertility estimated using random regression models.

    Science.gov (United States)

    Berry, D P; Buckley, F; Dillon, P; Evans, R D; Rath, M; Veerkamp, R F

    2003-11-01

    Genetic (co)variances between body condition score (BCS), body weight (BW), milk yield, and fertility were estimated using a random regression animal model extended to multivariate analysis. The data analyzed included 81,313 BCS observations, 91,937 BW observations, and 100,458 milk test-day yields from 8725 multiparous Holstein-Friesian cows. A cubic random regression was sufficient to model the changing genetic variances for BCS, BW, and milk across different days in milk. The genetic correlations between BCS and fertility changed little over the lactation; genetic correlations between BCS and interval to first service and between BCS and pregnancy rate to first service varied from -0.47 to -0.31, and from 0.15 to 0.38, respectively. This suggests that maximum genetic gain in fertility from indirect selection on BCS should be based on measurements taken in midlactation when the genetic variance for BCS is largest. Selection for increased BW resulted in shorter intervals to first service, but more services and poorer pregnancy rates; genetic correlations between BW and pregnancy rate to first service varied from -0.52 to -0.45. Genetic selection for higher lactation milk yield alone through selection on increased milk yield in early lactation is likely to have a more deleterious effect on genetic merit for fertility than selection on higher milk yield in late lactation.

  1. Instability of collective strong-interaction phenomena in hadron production as a possible origin of the weak and electromagnetic interactions

    International Nuclear Information System (INIS)

    Arnold, R.C.

    1975-12-01

    A systematic calculus of long-range Regge cut effects in multiparticle production is constructed in the form of an infrared-divergent stochastic field theory. Total cross sections and two-body overlap integrals in such a theory may depend very sensitively upon internal quantum-numbers of incident particles, resulting in a strong symmetry breaking at ultra-high energies. Such symmetry violations will influence low energy processes through dispersion relations, and a bootstrap of weak interactions becomes possible. A rough analytic estimate of the scale of thresholds for such effects yields a BCS-type gap equation, which expresses the scale of weak and electromagnetic couplings in terms of purely strong-interaction parameters

  2. Earlier and recent aspects of superconductivity

    International Nuclear Information System (INIS)

    Bednorz, J.G.; Muller, K.A.

    1990-01-01

    Contemporary knowledge of superconductivity is set against its historical background in this book. First, the highlights of superconductivity research in the twentieth century are reviewed. Further contributions then describe the basic phenomena resulting from the macroscopic quantum state of superconductivity (such as zero resistivity, the Meissner-Ochsenfeld effect, and flux quantization) and review possible mechanisms, including the classical BCS theory and the more recent alternative theories. The main categories of superconductors - elements, intermetallic phases, chalcogenides, oxides and organic compounds - are described. Common features and differences in their structure and electronic properties are pointed out. This overview of superconductivity is completed by a discussion of properties related to the coherence length

  3. Genetic relationship between body condition score, fertility, type and production traits in Brown Swiss dairy cows

    Directory of Open Access Journals (Sweden)

    Martino Cassandro

    2010-01-01

    Full Text Available This study aimed to investigate the relationship between body condition score (BCS, calving interval (CI, angularity (ANG, strength (FV and milk yield (MY on Brown Swiss cattle using data collected in the alpine provinces of Bolzano- Bozen and Trentino. The data set consisted of 28,538 test day records of BCS and MY from 3,282 Brown Swiss cows in lactation reared in 109 herds; production traits were merged with 13,796 repeated individual calving interval records and 38,711 type traits records. A multi-traits REML animal model was used to estimate (covariance components, with repeated observations. Heritability estimates for BCS, FV and ANG was 18%, 18% and 27%, respectively, while estimates for CI was very low (2%. Genetic correlations between CI and BCS was -0.44; between BCS and ANG was - 0.64; between BCS and MY was -0.35; between ANG and CI was 0.12. In conclusion, the selection for MY and ANG negatively affect fertility and average condition score of Brown cows. BCS recorded during lactation could be proposed as a useful trait for indirect selection aimed to improve fertility of cows.

  4. PTA and stenting for various types of Budd-Chiari syndrome

    International Nuclear Information System (INIS)

    Zhang Xinbao

    2011-01-01

    Objective: To investigate and evaluate PTA and stenting for various types of Budd-Chiari syndrome (BCS). Methods: 89 patients with BCS were diagnosed and treated during 7 years. The interventional procedures included: Percutaneous balloon dilatation (PBD) of inferior vena cava (IVC), PBD and stent placement for IVC, hepatic vein angioplasty via trans jugular vein, hepatic vein angioplasty via transhepatic and trans jugular approach, accessory hepatic vein angioplasty, percutaneous dual balloon dilatation for IVC and hepatic vein, and percutanous dual stent placement for IVC and hepatic vein. Results: The achievement ratio of PTA and stent placement was 96% and the mortality was 0%. The serious complication of PTA and stent placement of BCS was penetration into the pericardium, endovascular stent migration into right atrium. Conclusion: 1. PTA is a reliable procedures in treating type I a, II and III BCS, and TIPPS is useful for type I b BCS. But PTA and stenting is necessary for patients with type IV BCS. 2. Thrombolysis is needed for patients with type III, IV BCS. 3. Guiding of Color Doppler Ultrasound can improve the success of percutanous hepatic vein and reduce complications. (authors)

  5. International business theory and marketing theory

    OpenAIRE

    Soldner, Helmut

    1984-01-01

    International business theory and marketing theory : elements for internat. marketing theory building. - In: Marketing aspects of international business / Gerald M. Hampton ... (eds.). - Boston u.a. : Kluwer, 1984. - S. 25-57

  6. N=1 field theory duality from M theory

    International Nuclear Information System (INIS)

    Schmaltz, M.; Sundrum, R.

    1998-01-01

    We investigate Seiberg close-quote s N=1 field theory duality for four-dimensional supersymmetric QCD with the M-theory 5-brane. We find that the M-theory configuration for the magnetic dual theory arises via a smooth deformation of the M-theory configuration for the electric theory. The creation of Dirichlet 4-branes as Neveu-Schwarz 5-branes are passed through each other in type IIA string theory is given an elegant derivation from M theory. copyright 1998 The American Physical Society

  7. From chaos to unification: U theory vs. M theory

    International Nuclear Information System (INIS)

    Ye, Fred Y.

    2009-01-01

    A unified physical theory called U theory, that is different from M theory, is defined and characterized. U theory, which includes spinor and twistor theory, loop quantum gravity, causal dynamical triangulations, E-infinity unification theory, and Clifford-Finslerian unifications, is based on physical tradition and experimental foundations. In contrast, M theory pays more attention to mathematical forms. While M theory is characterized by supersymmetry string theory, U theory is characterized by non-supersymmetry unified field theory.

  8. Microscopic description of 258Fm fission dynamic with pairing

    Directory of Open Access Journals (Sweden)

    Scamps Guillaume

    2016-01-01

    Full Text Available Fission dynamic remains a challenge for nuclear microscopic theories. In order to understand the dynamic of the last stage of the fission process, the time-dependent Hartree-Fock approach with BCS pairing is applied to the describe the fission of the 258Fm. A good agreement is found for the one-body observables: the total kinetic energy and the average mass asymmetry. The non-physical dependence of two-body observables with the initial shape is discussed.

  9. Baking effect on Niobium superconducting RF cavities and its physical interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Saito, K. [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan); Kneisel, P. [Thomas Jefferson Accelerator Facility, VA, (United States)

    2000-07-01

    Recently a very surprising phenomenon has been discovered at JLab and Saclay with chemically polished niobium cavities, which the baking during vacuum evacuation has benefits to improve the cavity performance: high Q and high gradient. We have confirmed the same effect on the electropolished niobium cavities. We have analyzed the temperature dependence of the surface resistance in order to understand this effect in the frame or BCS theory. In this paper these results will be presented. (author)

  10. A course in theoretical physics

    CERN Document Server

    Shepherd, P J

    2013-01-01

    This book is a comprehensive account of five extended modules covering the key branches of twentieth-century theoretical physics, taught by the author over a period of three decades to students on bachelor and master university degree courses in both physics and theoretical physics. The modules cover nonrelativistic quantum mechanics, thermal and statistical physics, many-body theory, classical field theory (including special relativity and electromagnetism), and, finally, relativistic quantum mechanics and gauge theories of quark and lepton interactions, all presented in a single, self-contained volume. In a number of universities, much of the material covered (for example, on Einstein’s general theory of relativity, on the BCS theory of superconductivity, and on the Standard Model, including the theory underlying the prediction of the Higgs boson) is taught in postgraduate courses to beginning PhD students. A distinctive feature of the book is that full, step-by-step mathematical proofs of all essentia...

  11. 'Candidatus Phytoplasma noviguineense', a novel taxon associated with Bogia coconut syndrome and banana wilt disease on the island of New Guinea.

    Science.gov (United States)

    Miyazaki, Akio; Shigaki, Toshiro; Koinuma, Hiroaki; Iwabuchi, Nozomu; Rauka, Gou Bue; Kembu, Alfred; Saul, Josephine; Watanabe, Kiyoto; Nijo, Takamichi; Maejima, Kensaku; Yamaji, Yasuyuki; Namba, Shigetou

    2018-01-01

    Bogia coconut syndrome (BCS) is one of the lethal yellowing (LY)-type diseases associated with phytoplasma presence that are seriously threatening coconut cultivation worldwide. It has recently emerged, and is rapidly spreading in northern parts of the island of New Guinea. BCS-associated phytoplasmas collected in different regions were compared in terms of 16S rRNA gene sequences, revealing high identity among them represented by strain BCS-Bo R . Comparative analysis of the 16S rRNA gene sequences revealed that BCS-Bo R shared less than a 97.5 % similarity with other species of 'Candidatus Phytoplasma', with a maximum value of 96.08 % (with strain LY; GenBank accession no. U18747). This result indicates the necessity and propriety of a novel taxon for BCS phytoplasmas according to the recommendations of the IRPCM. Phylogenetic analysis was also conducted on 16S rRNA gene sequences, resulting in a monophyletic cluster composed of BCS-Bo R and other LY-associated phytoplasmas. Other phytoplasmas on the island of New Guinea associated with banana wilt and arecanut yellow leaf diseases showed high similarities to BCS-Bo R and were closely related to BCS phytoplasmas. Based on the uniqueness of their 16S rRNA gene sequences, a novel taxon 'Ca.Phytoplasma noviguineense' is proposed for these phytoplasmas found on the island of New Guinea, with strain BCS-Bo R (GenBank accession no. LC228755) as the reference strain. The novel taxon is described in detail, including information on the symptoms of associated diseases and additional genetic features of the secY gene and rp operon.

  12. COMPARISSON OF DIFFERENT IN VIVO ESTIMATORS OF BODY FAT AND MUSCLE CONTENT IN ADULT CREOLE GOATS

    Directory of Open Access Journals (Sweden)

    Hania Vilar-Martinez

    2009-06-01

    Full Text Available The objective of the present study was to compare the effectiveness of ultrasound measurements (ULT, body condition score (BCS and body mass index (BMI to predict body fat and muscle in goats. Twenty-four adult, ovariectomized, creole goats were fed individually to achieve dissimilar stable body weights (26 to 66 kg. After a six-week period of stabilization BCS was evaluated (average of 4 separate evaluations and BMI calculated (BW/(length x heightx10; average of 2 independent length and height measurements. Fat and muscle coverage over the dorsal (12-13th, lumbar (1st and coxal (1st vertebrae were measured by ultrasound imaging. Animals were slaughtered and visceral fat dissected and weighed. Left half carcass weights were obtained and muscle and fat were dissected and weighed. Left half carcass data were adjusted to whole carcass data. Simple  regression analyses were performed with ULT, BCS and BMI as predictors and visceral (VF, carcass (CF and total fat (TF, and muscle (MU as response variables. Coefficients of variation (CV were calculated for BCS and BMI estimations. ULT measurement of total tissue (fat + muscle coverage over dorsal vertebrae presented the highest predictive value for ULT measurements; thus this measurement is the only reported. Coefficients of determination (R2 for VF, CF and TF were .55, .76 and .68; .78, .82 and .87; .81, .81 and .88 for ULT, BCS and BMI as predictors. R2 for MU were .67, .84 and .76 using ULT, BCS and BMI as predictors. R2 for proportions of VF/BW, CF/BW and TF/BW were .47, .73 and .65; .75, .78 and .88; .74, .71 and .85; when ULT, BCS and BMI were used as predictors. R2 for MS/BW were ≤ .10 using ULT, BCS and BMI as predictors. CV was greater in BCS estimation as compared to BMI estimation (9.7 vs. 3.1 %. BCS and BMI were more accurate in vivo predictors than ULT for body fat content, fat as proportion of BW and body muscle content. ULT, BCS and BMI were completely worthless for predicting

  13. Late Holocene earthquake history of the Brigham City segment of the Wasatch fault zone at the Hansen Canyon, Kotter Canyon, and Pearsons Canyon trench sites, Box Elder County, Utah

    Science.gov (United States)

    DuRoss, Christopher B.; Personius, Stephen F.; Crone, Anthony J.; McDonald, Greg N.; Briggs, Richard W.

    2012-01-01

    Of the five central segments of the Wasatch fault zone (WFZ) having evidence of recurrent Holocene surface-faulting earthquakes, the Brigham City segment (BCS) has the longest elapsed time since its most recent surface-faulting event (~2.1 kyr) compared to its mean recurrence time between events (~1.3 kyr). Thus, the BCS has the highest time-dependent earthquake probability of the central WFZ. We excavated trenches at three sites––the Kotter Canyon and Hansen Canyon sites on the north-central BCS and Pearsons Canyon site on the southern BCS––to determine whether a surface-faulting earthquake younger than 2.1 ka occurred on the BCS. Paleoseismic data for Hansen Canyon and Kotter Canyon confirm that the youngest earthquake on the north-central BCS occurred before 2 ka, consistent with previous north-central BCS investigations at Bowden Canyon and Box Elder Canyon. At Hansen Canyon, the most recent earthquake is constrained to 2.1–4.2 ka and had 0.6–2.5 m of vertical displacement. At Kotter Canyon, we found evidence for two events at 2.5 ± 0.3 ka and 3.5 ± 0.3 ka, with an average displacement per event of 1.9–2.3 m. Paleoseismic data from Pearsons Canyon, on the previously unstudied southern BCS, indicate that a post-2 ka earthquake ruptured this part of the segment. The Pearsons Canyon earthquake occurred at 1.2 ± 0.04 ka and had 0.1–0.8 m of vertical displacement, consistent with our observation of continuous, youthful scarps on the southern 9 km of the BCS having 1–2 m of late Holocene(?) surface offset. The 1.2-ka earthquake on the southern BCS likely represents rupture across the Weber–Brigham City segment boundary from the penultimate Weber-segment earthquake at about 1.1 ka. The Pearsons Canyon data result in a revised length of the BCS that has not ruptured since 2 ka (with time-dependent probability implications), and provide compelling evidence of at least one segment-boundary failure and multi-segment rupture on the central WFZ. Our

  14. Generalizability theory and item response theory

    OpenAIRE

    Glas, Cornelis A.W.; Eggen, T.J.H.M.; Veldkamp, B.P.

    2012-01-01

    Item response theory is usually applied to items with a selected-response format, such as multiple choice items, whereas generalizability theory is usually applied to constructed-response tasks assessed by raters. However, in many situations, raters may use rating scales consisting of items with a selected-response format. This chapter presents a short overview of how item response theory and generalizability theory were integrated to model such assessments. Further, the precision of the esti...

  15. Assessment of Body Condition in African (Loxodonta africana and Asian (Elephas maximus Elephants in North American Zoos and Management Practices Associated with High Body Condition Scores.

    Directory of Open Access Journals (Sweden)

    Kari A Morfeld

    Full Text Available Obesity has a negative effect on health and welfare of many species, and has been speculated to be a problem for zoo elephants. To address this concern, we assessed the body condition of 240 elephants housed in North American zoos based on a set of standardized photographs using a 5-point Body Condition Score index (1 = thinnest; 5 = fattest. A multi-variable regression analysis was then used to determine how demographic, management, housing, and social factors were associated with an elevated body condition score in 132 African (Loxodonta africana and 108 Asian (Elephas maximus elephants. The highest BCS of 5, suggestive of obesity, was observed in 34% of zoo elephants. In both species, the majority of elephants had elevated BCS, with 74% in the BCS 4 (40% and 5 (34% categories. Only 22% of elephants had BCS 3, and less than 5% of the population was assigned the lowest BCS categories (BCS 1 and 2. The strongest multi-variable model demonstrated that staff-directed walking exercise of 14 hours or more per week and highly unpredictable feeding schedules were associated with decreased risk of BCS 4 or 5, while increased diversity in feeding methods and being female was associated with increased risk of BCS 4 or 5. Our data suggest that high body condition is prevalent among North American zoo elephants, and management strategies that help prevent and mitigate obesity may lead to improvements in welfare of zoo elephants.

  16. Prevalence of Budd-Chiari Syndrome during Pregnancy or Puerperium: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Weirong Ren

    2015-01-01

    Full Text Available Women during pregnancy or puerperium are likely to develop Budd-Chiari syndrome (BCS. However, the reported prevalence of pregnancy-related BCS varied considerably among studies. Our study aims to systematically review this issue. Overall, 817 papers were initially identified via the PubMed, EMBASE, China National Knowledge Infrastructure, and Chinese Scientific and Technological Journal databases. Twenty of them were eligible. The prevalence of pregnancy-related BCS varied from 0% to 21.5%. The pooled prevalence was 6.8% (95% CI: 3.9–10.5% in all BCS patients, 6.3% (95% CI: 3.8–9.4% in primary BCS patients, and 13.1% (95% CI: 7.1–20.7% in female BCS patients. Among them, one study was carried out in Africa with a prevalence of 10.6%; 14 studies in Asian countries with a pooled prevalence of 7.1% (95% CI: 3.1–12.6%; and 5 studies in European countries with a pooled prevalence of 5.0% (95% CI: 3.1–7.3%. The pooled prevalence was 6.7% (95% CI: 2.6–12.3% in studies published before 2005 and 7.3% (95% CI: 4.2–12.5% in those published after 2005. In conclusion, pregnancy is a relatively common risk factor for BCS, but there is a huge variation in the prevalence among studies. Physicians should be aware of pregnancy-related BCS.

  17. Body condition score of Nellore beef cows: a heritable measure to improve the selection of reproductive and maternal traits.

    Science.gov (United States)

    Fernandes, A F A; Neves, H H R; Carvalheiro, R; Oliveira, J A; Queiroz, S A

    2015-08-01

    Despite the economic importance of beef cattle production in Brazil, female reproductive performance, which is strongly associated with production efficiency, is not included in the selection index of most breeding programmes due to low heritability and difficulty in measure. The body condition score (BCS) could be used as an indicator of these traits. However, so far little is known about the feasibility of using BCS as a selection tool for reproductive performance in beef cattle. In this study, we investigated the sources of variation in the BCS of Nellore beef cows, quantified its association with reproductive and maternal traits and estimated its heritability. BCS was analysed using a logistic model that included the following effects: contemporary group at weaning, cow weight and hip height, calving order, reconception together with the weight and scores of conformation and early finishing assigned to calves at weaning. In the genetic analysis, variance components of BCS were estimated through Bayesian inference by fitting an animal model that also included the aforementioned effects. The results showed that BCS was significantly associated with all of the reproductive and maternal variables analysed. The estimated posterior mean of heritability of BCS was 0.24 (highest posterior density interval at 95%: 0.093 to 0.385), indicating an involvement of additive gene action in its determination. The present findings show that BCS can be used as a selection criterion for Nellore females.

  18. Genetic correlations between body condition scores and fertility in dairy cattle using bivariate random regression models.

    Science.gov (United States)

    De Haas, Y; Janss, L L G; Kadarmideen, H N

    2007-10-01

    Genetic correlations between body condition score (BCS) and fertility traits in dairy cattle were estimated using bivariate random regression models. BCS was recorded by the Swiss Holstein Association on 22,075 lactating heifers (primiparous cows) from 856 sires. Fertility data during first lactation were extracted for 40,736 cows. The fertility traits were days to first service (DFS), days between first and last insemination (DFLI), calving interval (CI), number of services per conception (NSPC) and conception rate to first insemination (CRFI). A bivariate model was used to estimate genetic correlations between BCS as a longitudinal trait by random regression components, and daughter's fertility at the sire level as a single lactation measurement. Heritability of BCS was 0.17, and heritabilities for fertility traits were low (0.01-0.08). Genetic correlations between BCS and fertility over the lactation varied from: -0.45 to -0.14 for DFS; -0.75 to 0.03 for DFLI; from -0.59 to -0.02 for CI; from -0.47 to 0.33 for NSPC and from 0.08 to 0.82 for CRFI. These results show (genetic) interactions between fat reserves and reproduction along the lactation trajectory of modern dairy cows, which can be useful in genetic selection as well as in management. Maximum genetic gain in fertility from indirect selection on BCS should be based on measurements taken in mid lactation when the genetic variance for BCS is largest, and the genetic correlations between BCS and fertility is strongest.

  19. Teaching Theory X and Theory Y in Organizational Communication

    Science.gov (United States)

    Noland, Carey

    2014-01-01

    The purpose of the activity described here is to integrate McGregor's Theory X and Theory Y into a group application: design a syllabus that embodies either Theory X or Theory Y tenets. Students should be able to differentiate between Theory X and Theory Y, create a syllabus based on Theory X or Theory Y tenets, evaluate the different syllabi…

  20. Massive IIA string theory and Matrix theory compactification

    International Nuclear Information System (INIS)

    Lowe, David A.; Nastase, Horatiu; Ramgoolam, Sanjaye

    2003-01-01

    We propose a Matrix theory approach to Romans' massive Type IIA supergravity. It is obtained by applying the procedure of Matrix theory compactifications to Hull's proposal of the massive Type IIA string theory as M-theory on a twisted torus. The resulting Matrix theory is a super-Yang-Mills theory on large N three-branes with a space-dependent noncommutativity parameter, which is also independently derived by a T-duality approach. We give evidence showing that the energies of a class of physical excitations of the super-Yang-Mills theory show the correct symmetry expected from massive Type IIA string theory in a lightcone quantization

  1. Theories of Career Development. A Comparison of the Theories.

    Science.gov (United States)

    Osipow, Samuel H.

    These seven theories of career development are examined in previous chapters: (1) Roe's personality theory, (2) Holland's career typology theory, (3) the Ginzberg, Ginsburg, Axelrod, and Herma Theory, (4) psychoanalytic conceptions, (5) Super's developmental self-concept theory, (6) other personality theories, and (7) social systems theories.…

  2. Comparison of early quality of life in patients treated with radiotherapy following mastectomy or breast conservation therapy: A prospective study

    International Nuclear Information System (INIS)

    Munshi, Anusheel; Dutta, Debnarayan; Kakkar, Sajal; Budrukkar, Ashwini; Jalali, Rakesh; Sarin, Rajiv; Gupta, Sudeep; Parmar, Vani; Badwe, Rajendra

    2010-01-01

    Introduction: To compare quality of life (QOL) in breast cancer patients from a developing country after breast conservation surgery (BCS) or mastectomy and adjuvant radiotherapy (RT). Materials and methods: In a 6-month period, all consecutive early and locally advanced breast cancer patients treated with either BCS or mastectomy and treated with RT were analyzed. All patients who underwent mastectomy were treated with 45 Gray/20/4 weeks. Patients with BCS were treated with a dose of 45-50 Gray/25/5 weeks to whole breast followed by tumor bed boost (15 Gray/6/6 days with suitable energy electrons). Prospective evaluation of QOL using EORTC QLQ C30 and breast cancer specific QLQ BR23 was done before starting RT (baseline), at mid-RT and at RT conclusion for all patients. Results: One hundred and thirteen patients had mastectomy and 142 patients underwent BCS. Reliability test (Cronbach alpha) for questionnaire filling was 0.669-0.886. At pre-RT assessment, global QOL scores in mastectomy and BCS groups were 71.1 and 71.3, respectively. There was no significant difference in pre-RT EORTC QLQ C30 functional and symptom domains between mastectomy and BCS patients. However, social function domain score was higher in patients who underwent mastectomy (83 versus 73.9; p = 0.018). In QLQ BR23 domains, body image and sexual functioning domains were similar between the two groups. However, sexual enjoyment (10.9 versus 47.6; p = 0.006) and future perspective (7.4 versus 37.1; p = 0.036) domains were significantly better in BCS arm. There was no difference between systemic side effect (BRSSE), breast symptom (BRBS) and arm symptom (BRAS) domain scores between the groups. There was no significant difference in change of QOL scores between mastectomy and BCS patients at RT completion as compared to baseline. Conclusions: There was no significant difference in quality of life in patients with BCS versus those with mastectomy. However, patients who underwent BCS had better

  3. Reduced cortisol and metabolic responses of thin ewes to an acute cold challenge in mid-pregnancy: implications for animal physiology and welfare.

    Directory of Open Access Journals (Sweden)

    Else Verbeek

    Full Text Available BACKGROUND: Low food availability leading to reductions in Body Condition Score (BCS; 0 indicates emaciation and 5 obesity in sheep often coincides with low temperatures associated with the onset of winter in New Zealand. The ability to adapt to reductions in environmental temperature may be impaired in animals with low BCS, in particular during pregnancy when metabolic demand is higher. Here we assess whether BCS affects a pregnant animal's ability to cope with cold challenges. METHODS: Eighteen pregnant ewes with a BCS of 2.7±0.1 were fed to attain low (LBC: BCS2.3±0.1, medium (MBC: BCS3.2±0.2 or high BCS (HBC: BCS3.6±0.2. Shorn ewes were exposed to a 6-h acute cold challenge in a climate-controlled room (wet and windy conditions, 4.4±0.1°C in mid-pregnancy. Blood samples were collected during the BCS change phase, acute cold challenge and recovery phase. RESULTS: During the BCS change phase, plasma glucose and leptin concentrations declined while free fatty acids (FFA increased in LBC compared to MBC (P<0.01, P<0.01 and P<0.05, respectively and HBC ewes (P<0.05, P<0.01 and P<0.01, respectively. During the cold challenge, plasma cortisol concentrations were lower in LBC than MBC (P<0.05 and HBC ewes (P<0.05, and FFA and insulin concentrations were lower in LBC than HBC ewes (P<0.05 and P<0.001, respectively. Leptin concentrations declined in MBC and HBC ewes while remaining unchanged in LBC ewes (P<0.01. Glucose concentrations and internal body temperature (T(core increased in all treatments, although peak T(core tended to be higher in HBC ewes (P<0.1. During the recovery phase, T4 concentrations were lower in LBC ewes (P<0.05. CONCLUSION: Even though all ewes were able to increase T(core and mobilize glucose, low BCS animals had considerably reduced cortisol and metabolic responses to a cold challenge in mid-pregnancy, suggesting that their ability to adapt to cold challenges through some of the expected pathways was reduced.

  4. Barriers to breast cancer screening participation among Jordanian and Palestinian American women.

    Science.gov (United States)

    Kawar, Lina Najib

    2013-02-01

    Increasing breast cancer screening (BCS) among diverse women from minority groups is a goal of health care providers and national organizations as a way to help in the early detection and treatment of breast cancer. The purpose of this article is to investigate barriers to BCS encountered by Jordanian and Palestinian women living in the United States (US). Descriptive content analysis of interviews of 107 Jordanian and Palestinian immigrant women provided data on BCS barriers that were thematically analyzed. Data revealed 4 barriers that affect Jordanian and Palestinian immigrant women's participation in BCS: (1) culture-specific barriers such as embarrassment, family relationships, fatalism, and traditional healers consultation; (2) immigration-related barriers (citizenship issues and language); (3) general barriers (including nonparticipation in health screening, stigmatization of cancer, fear, and ignorance about BCS); and (4) irrelevant barriers. Clinicians should be cognizant of the culture, beliefs and practices of Arab Middle Eastern immigrant women and the influence of these factors on their decision to participate in routine BCS. To increase participation in BCS and knowledge of breast cancer, appropriate language and culturally sensitive educational materials should be created and made available to Arab Middle Eastern immigrant women. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Do socioeconomic factors influence breast cancer screening practices among Arab women in Qatar?

    Science.gov (United States)

    Donnelly, Tam Truong; Al Khater, Al-Hareth; Al Kuwari, Mohamed Ghaith; Al-Bader, Salha Bujassoum; Al-Meer, Nabila; Abdulmalik, Mariam; Singh, Rajvir; Chaudhry, Sofia; Fung, Tak

    2015-01-22

    Breast cancer incidence rates are rising in Qatar. Although the Qatari government provides subsidised healthcare and screening programmes that reduce cost barriers for residents, breast cancer screening (BCS) practices among women remain low. This study explores the influence of socioeconomic status on BCS among Arab women in Qatar. A multicentre, cross-sectional quantitative survey was conducted with 1063 Arab women (87.5% response rate) in Qatar from March 2011 to July 2011. Women who were 35 years or older and had lived in Qatar for at least 10 years were recruited from seven primary healthcare centres and women's health clinics in urban and semiurban regions of Qatar. Associations between socioeconomic factors and BCS practice were estimated using χ(2) tests and multivariate logistic regression analyses. Findings indicate that less than one-third of the participants practised BCS appropriately, whereas less than half of the participants were familiar with recent BCS guidelines. Married women and women with higher education and income levels were significantly more likely to be aware of and to practise BCS than women who had lower education and income levels. Findings indicate low levels of awareness and low participation rates in BCS among Arab women in Qatar. Socioeconomic factors influence these women's participation in BCS activities. The strongest predictors for BCS practice are higher education and higher income levels. Additional research is needed to explore the impact of economic factors on healthcare seeking behaviours in the Middle Eastern countries that have a high national gross domestic product where healthcare services are free or heavily subsidised by the government; promotion of BCS and intervention strategies in these countries should focus on raising awareness about breast cancer, the cost and benefit of early screening for this disease, particularly among low-income women. Published by the BMJ Publishing Group Limited. For permission to

  6. Genetic correlations among body condition score, yield, and fertility in first-parity cows estimated by random regression models.

    Science.gov (United States)

    Veerkamp, R F; Koenen, E P; De Jong, G

    2001-10-01

    Twenty type classifiers scored body condition (BCS) of 91,738 first-parity cows from 601 sires and 5518 maternal grandsires. Fertility data during first lactation were extracted for 177,220 cows, of which 67,278 also had a BCS observation, and first-lactation 305-d milk, fat, and protein yields were added for 180,631 cows. Heritabilities and genetic correlations were estimated using a sire-maternal grandsire model. Heritability of BCS was 0.38. Heritabilities for fertility traits were low (0.01 to 0.07), but genetic standard deviations were substantial, 9 d for days to first service and calving interval, 0.25 for number of services, and 5% for first-service conception. Phenotypic correlations between fertility and yield or BCS were small (-0.15 to 0.20). Genetic correlations between yield and all fertility traits were unfavorable (0.37 to 0.74). Genetic correlations with BCS were between -0.4 and -0.6 for calving interval and days to first service. Random regression analysis (RR) showed that correlations changed with days in milk for BCS. Little agreement was found between variances and correlations from RR, and analysis including a single month (mo 1 to 10) of data for BCS, especially during early and late lactation. However, this was due to excluding data from the conventional analysis, rather than due to the polynomials used. RR and a conventional five-traits model where BCS in mo 1, 4, 7, and 10 was treated as a separate traits (plus yield or fertility) gave similar results. Thus a parsimonious random regression model gave more realistic estimates for the (co)variances than a series of bivariate analysis on subsets of the data for BCS. A higher genetic merit for yield has unfavorable effects on fertility, but the genetic correlation suggests that BCS (at some stages of lactation) might help to alleviate the unfavorable effect of selection for higher yield on fertility.

  7. Supersymmetric gauge theories from string theory; Theorie de jauge supersymetrique de la theorie des cordes

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, St

    2005-12-15

    This thesis presents various ways to construct four-dimensional quantum field theories from string theory. In a first part we study the generation of a supersymmetric Yang-Mills theory, coupled to an adjoint chiral superfield, from type IIB string theory on non-compact Calabi-Yau manifolds, with D-branes wrapping certain sub-cycles. Properties of the gauge theory are then mapped to the geometric structure of the Calabi-Yau space. Even if the Calabi-Yau geometry is too complicated to evaluate the geometric integrals explicitly, one can then always use matrix model perturbation theory to calculate the effective superpotential. The second part of this work covers the generation of four-dimensional super-symmetric gauge theories, carrying several important characteristic features of the standard model, from compactifications of eleven-dimensional supergravity on G{sub 2}-manifolds. If the latter contain conical singularities, chiral fermions are present in the four-dimensional gauge theory, which potentially lead to anomalies. We show that, locally at each singularity, these anomalies are cancelled by the non-invariance of the classical action through a mechanism called 'anomaly inflow'. Unfortunately, no explicit metric of a compact G{sub 2}-manifold is known. Here we construct families of metrics on compact weak G{sub 2}-manifolds, which contain two conical singularities. Weak G{sub 2}-manifolds have properties that are similar to the ones of proper G{sub 2}-manifolds, and hence the explicit examples might be useful to better understand the generic situation. Finally, we reconsider the relation between eleven-dimensional supergravity and the E{sub 8} x E{sub 8}-heterotic string. This is done by carefully studying the anomalies that appear if the supergravity theory is formulated on a ten-manifold times the interval. Again we find that the anomalies cancel locally at the boundaries of the interval through anomaly inflow, provided one suitably modifies the

  8. A Future of Communication Theory: Systems Theory.

    Science.gov (United States)

    Lindsey, Georg N.

    Concepts of general systems theory, cybernetics and the like may provide the methodology for communication theory to move from a level of technology to a level of pure science. It was the purpose of this paper to (1) demonstrate the necessity of applying systems theory to the construction of communication theory, (2) review relevant systems…

  9. Gelatin films plasticized with a simulated biodiesel coproduct stream

    Directory of Open Access Journals (Sweden)

    2009-04-01

    Full Text Available In order to explore the possibility of substituting an unrefined biodiesel coproduct stream (BCS for refined glycerol as a polymer plasticizer we have prepared cast gelatin films plasticized with a simulated BCS, i.e., mixtures of glycerol and some of the typical components found in BCS (methyl linoleate, methyl oleate, linoleic acid, and oleic acid. We measured the tensile properties as a function of plasticizer composition, and analyzed the specific effect of each individual component on tensile properties. We found that it is the unrecovered alkyl esters that largely determine the tensile properties, and that BCS can be successfully used to plasticize cast gelatin films as long as the BCS contains 11 parts by weight, or less, of unrecovered alkyl esters per 100 parts glycerol.

  10. Gauge theory loop operators and Liouville theory

    International Nuclear Information System (INIS)

    Drukker, Nadav; Teschner, Joerg

    2009-10-01

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

  11. 23rd Annual seminar on theoretical physics, Grahamstown, 5-8 July 1988

    International Nuclear Information System (INIS)

    1988-01-01

    This seminar contains 18 papers. Twelve papers are indexed separately. Topics covered include: the Dirac equation in arbitrary space-time dimensions; next-to-leading corrections to jet multiplicity distributions in QCD; propagators and one loop diagrams in cavity field theory; cavity quantum chromodynamics in the presence of a classical background field; quark gluon plasma and hadronic matter in the early universe; deconfinement and chiral transitions in lattice QCD; J/Ψ suppression as a signal for quark deconfinement; geometrical interpretation of boson models of nuclear structure; the interacting boson model, BCS-RPA theory and the theory of pairing interactions applied to the Ge-nuclei; fluctuations and chaotic behaviour; test of the Bonn nucleon-nucleon potential in nucleon-antinucleon scattering; and new relativistic centre-of-mass corrections for the nucleon

  12. New world of Gossamer superconductivity

    International Nuclear Information System (INIS)

    Maki, Kazumi; Haas, Stephan; Parker, David; Won, Hyekyung; Dora, Balazs; Virosztek, Attila

    2006-01-01

    Since the discovery of the high-T c cuprate superconductor La 2-x BaCuO 4 in 1986 by Bednorz and Mueller, controversy regarding the nature or origin of this remarkable superconductivity has continued. However, d-wave superconductivity in the hole-doped cuprates, arising due to the anti-paramagnon exchange, was established around 1994. More recently we have shown that the mean field theory, like the BCS theory of superconductivity and Landau's Fermi liquid theory are adequate to describe the cuprates. The keys for this development are the facts that a) the pseudogap phase is d-wave density wave (dDW) and that the high-T c cuprate superconductivity is gossamer (i.e. it exists in the presence of dDW). (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. Situation-specific theories from the middle-range transitions theory.

    Science.gov (United States)

    Im, Eun-Ok

    2014-01-01

    The purpose of this article was to analyze the theory development process of the situation-specific theories that were derived from the middle-range transitions theory. This analysis aims to provide directions for future development of situation-specific theories. First, transitions theory is concisely described with its history, goal, and major concepts. Then, the approach that was used to retrieve the situation-specific theories derived from transitions theory is described. Next, an analysis of 6 situation-specific theories is presented. Finally, 4 themes reflecting commonalities and variances in the theory development process are discussed with implications for future theoretical development.

  14. Stent Angioplasty of Closed Mesocaval Shunt in a Patient with Budd-Chiari Syndrome

    International Nuclear Information System (INIS)

    Sancak, Tanzer; Karagulle, Ayse Tuba; Bilgic, Sadik; Sanlidilek, Umman; Yerdel, Mehmet Ali

    2002-01-01

    Budd-Chiari syndrome (BCS) is an uncommon disorder caused by hepatic venous outflow obstruction. It is characterized by ascites, hepatomegaly and abdominal pain. Percutaneous intervention shave recently been used for the treatment of BCS. We present a case of BCS with a closed mesocaval shunt which was reopened with a self-expandable metallic stent

  15. Gauge theories as string theories: the first results

    International Nuclear Information System (INIS)

    Gorsky, Aleksandr S

    2005-01-01

    The gauge/string theory duality in curved space is discussed mainly using a non-Abelian conformal N = 4 supersymmetric gauge theory and the theory of a closed superstring in the AdS 5 x S 5 metric as an example. It is shown that in the supergravity approximation, string duality yields the characteristics of a strong-coupling gauge theory. For a special shape of the contour, a Wilson loop expression is derived in the classical superstring approximation. The role of the hidden integrability in lower-loop calculations in gauge theory and in different approximations of string theory is discussed. It is demonstrated that in the large quantum-number limit, gauge theory operators can be described in terms of the dual string picture. Examples of metrics providing the dual description of gauge theories with broken conformal symmetry are presented, and formulations of the vacuum structure of such theories in terms of gravity are discussed. (reviews of topical problems)

  16. Superconductivity

    CERN Document Server

    Poole, Charles P; Farach, Horacio A

    1995-01-01

    Superconductivity covers the nature of the phenomenon of superconductivity. The book discusses the fundamental principles of superconductivity; the essential features of the superconducting state-the phenomena of zero resistance and perfect diamagnetism; and the properties of the various classes of superconductors, including the organics, the buckministerfullerenes, and the precursors to the cuprates. The text also describes superconductivity from the viewpoint of thermodynamics and provides expressions for the free energy; the Ginzburg-Landau and BCS theories; and the structures of the high

  17. Detecting nonlocal Cooper pair entanglement by optical Bell inequality violation

    OpenAIRE

    Nigg, Simon E.; Tiwari, Rakesh P.; Walter, Stefan; Schmidt, Thomas L.

    2014-01-01

    Based on the Bardeen Cooper Schrieffer (BCS) theory of superconductivity, the coherent splitting of Cooper pairs from a superconductor to two spatially separated quantum dots has been predicted to generate nonlocal pairs of entangled electrons. In order to test this hypothesis, we propose a scheme to transfer the spin state of a split Cooper pair onto the polarization state of a pair of optical photons. We show that the produced photon pairs can be used to violate a Bell inequality, unambiguo...

  18. High-Tc cuprate superconductivity in a nutshell

    International Nuclear Information System (INIS)

    Won, Hyekyung; Haas, Stephan; Parker, David; Maki, Kazumi

    2005-01-01

    Since the discovery of high-T c cuprate superconductivity in 1986 many new experimental techniques and theoretical concepts have been developed. In particular it was shown that the BCS theory of d-wave superconductivity describes semi-quantitatively the high-T c superconductivity. Furthermore, it was demonstrated that Volovik's approach is extremely useful for finding the quasiparticle properties in the vortex state. Here we survey these developments and forecast future directions. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Dualities in M-theory and Born-Infeld Theory

    International Nuclear Information System (INIS)

    Brace, Daniel M.

    2001-01-01

    We discuss two examples of duality. The first arises in the context of toroidal compactification of the discrete light cone quantization of M-theory. In the presence of nontrivial moduli coming from the M-theory three form, it has been conjectured that the system is described by supersymmetric Yang-Mills gauge theory on a noncommutative torus. We are able to provide evidence for this conjecture, by showing that the dualities of this M-theory compactification, which correspond to T-duality in Type IIA string theory, are also dualities of the noncommutative supersymmetric Yang-Mills description. One can also consider this as evidence for the accuracy of the Matrix Theory description of M-theory in this background. The second type of duality is the self-duality of theories with U(1) gauge fields. After discussing the general theory of duality invariance for theories with complex gauge fields, we are able to find a generalization of the well known U(1) Born-Infeld theory that contains any number of gauge fields and which is invariant under the maximal duality group. We then find a supersymmetric extension of our results, and also show that our results can be extended to find Born-Infeld type actions in any even dimensional spacetime

  20. Ethnodrama: An Innovative Knowledge Translation Tool in the Management of Lymphedema.

    Science.gov (United States)

    Ahmed, Shahid; Quinlan, Elizabeth; McMullen, Linda; Thomas, Roanne; Fichtner, Pam; Block, Janice

    2015-01-01

    Lymphedema can cause significant physical impairment and quality-of-life issues. Yet there is a gap in knowledge about lymphedema among breast cancer survivors (BCS), and health care professionals (HCP). Ethnodrama is an innovative knowledge translation strategy that uses theatrical performances for dissemination of research results. We evaluated the impact of live ethnodrama on HCP' and BCS' awareness and attitudes in relation to impact of lymphedema on BCS' lives. Ethnodrama performances were developed by script writers and a theatre director in collaboration with the investigators and BCS using data from published research and pre-performances workshops. Six interactive live performances were given to audiences of BCS, HCP, and community members in four cities across Canada. After watching these live performances, members of the audiences were asked to complete a paper-based questionnaire regarding their knowledge of lymphedema, and their attitudes and practices toward lymphedema. Of 238 audience members who participated in the survey, 55 (23%) were BCS and 85 (37.5%) were HCP. Most members rated the performances as very effective in changing their (84%) or other people's (93%) understanding of lymphedema; 96% reported being motivated to seek additional information on lymphedema, and 72% of HCP anticipated changes in their practices related to lymphedema screening. Overall no significant differences were noted in responses to ethnodrama between BCS and HCP. Open-ended responses were supportive of the findings from the closed-ended questions. Our results indicate that ethnodrama performances effectively convey information and positively affecting changes in HCP' and BCS' attitudes toward lymphedema.

  1. M(atrix) theory: matrix quantum mechanics as a fundamental theory

    International Nuclear Information System (INIS)

    Taylor, Washington

    2001-01-01

    This article reviews the matrix model of M theory. M theory is an 11-dimensional quantum theory of gravity that is believed to underlie all superstring theories. M theory is currently the most plausible candidate for a theory of fundamental physics which reconciles gravity and quantum field theory in a realistic fashion. Evidence for M theory is still only circumstantial -- no complete background-independent formulation of the theory exists as yet. Matrix theory was first developed as a regularized theory of a supersymmetric quantum membrane. More recently, it has appeared in a different guise as the discrete light-cone quantization of M theory in flat space. These two approaches to matrix theory are described in detail and compared. It is shown that matrix theory is a well-defined quantum theory that reduces to a supersymmetric theory of gravity at low energies. Although its fundamental degrees of freedom are essentially pointlike, higher-dimensional fluctuating objects (branes) arise through the non-Abelian structure of the matrix degrees of freedom. The problem of formulating matrix theory in a general space-time background is discussed, and the connections between matrix theory and other related models are reviewed

  2. Gauge theory loop operators and Liouville theory

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-10-15

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

  3. Supersymmetric gauge theories from string theory

    International Nuclear Information System (INIS)

    Metzger, St.

    2005-12-01

    This thesis presents various ways to construct four-dimensional quantum field theories from string theory. In a first part we study the generation of a supersymmetric Yang-Mills theory, coupled to an adjoint chiral superfield, from type IIB string theory on non-compact Calabi-Yau manifolds, with D-branes wrapping certain sub-cycles. Properties of the gauge theory are then mapped to the geometric structure of the Calabi-Yau space. Even if the Calabi-Yau geometry is too complicated to evaluate the geometric integrals explicitly, one can then always use matrix model perturbation theory to calculate the effective superpotential. The second part of this work covers the generation of four-dimensional super-symmetric gauge theories, carrying several important characteristic features of the standard model, from compactifications of eleven-dimensional supergravity on G 2 -manifolds. If the latter contain conical singularities, chiral fermions are present in the four-dimensional gauge theory, which potentially lead to anomalies. We show that, locally at each singularity, these anomalies are cancelled by the non-invariance of the classical action through a mechanism called 'anomaly inflow'. Unfortunately, no explicit metric of a compact G 2 -manifold is known. Here we construct families of metrics on compact weak G 2 -manifolds, which contain two conical singularities. Weak G 2 -manifolds have properties that are similar to the ones of proper G 2 -manifolds, and hence the explicit examples might be useful to better understand the generic situation. Finally, we reconsider the relation between eleven-dimensional supergravity and the E 8 x E 8 -heterotic string. This is done by carefully studying the anomalies that appear if the supergravity theory is formulated on a ten-manifold times the interval. Again we find that the anomalies cancel locally at the boundaries of the interval through anomaly inflow, provided one suitably modifies the classical action. (author)

  4. Group theory for chemists fundamental theory and applications

    CERN Document Server

    Molloy, K C

    2010-01-01

    The basics of group theory and its applications to themes such as the analysis of vibrational spectra and molecular orbital theory are essential knowledge for the undergraduate student of inorganic chemistry. The second edition of Group Theory for Chemists uses diagrams and problem-solving to help students test and improve their understanding, including a new section on the application of group theory to electronic spectroscopy.Part one covers the essentials of symmetry and group theory, including symmetry, point groups and representations. Part two deals with the application of group theory t

  5. Health-related quality of life in long-term breast cancer survivors

    DEFF Research Database (Denmark)

    Peuckmann, Vera; Ekholm, Ola; Rasmussen, Niels Kristian

    2007-01-01

    AIM: To investigate health-related quality of life (HRQOL) in a nationally representative sample of long-term breast cancer survivors (BCS) in Denmark. PARTICIPANTS AND METHODS: An age-stratified random sample of 2,000 female BCS > or = 5 years after primary surgery without recurrence was drawn...... from the Danish Breast Cancer Cooperative Group register, which is representative regarding long-term BCS in Denmark, and compared with 3,104 women of the nationally representative Danish Health and Morbidity Survey 2000. The Short Form-36 questionnaire assessed HRQOL and its association with BCS...... health" (P mental health" (P

  6. Professional Business Connectivity Services in SharePoint 2010

    CERN Document Server

    Hillier, Scot

    2011-01-01

    Comprehensive coverage on Business Connectivity Services within SharePoint 2010 As Microsoft's new multipurpose portal technology, Business Connectivity Services (BCS) is a brand new way for SharePoint users to seamlessly access and integrate data from any application or databases within SharePoint 2010. With this in-depth guide, a team of SharePoint experts walks you through the features of the new BCS, including the ability for users to view and modify the data from SharePoint 2010 with BCS. You'll explore how to use BCS, deploy solutions, create external content types and lists, create .NET

  7. Renormalization effects and phonon density of states in high temperature superconductors

    Directory of Open Access Journals (Sweden)

    Vinod Ashokan

    2013-02-01

    Full Text Available Using the versatile double time thermodynamic Green's function approach based on many body theory the renormalized frequencies, phonon energy line widths, shifts and phonon density of states (PDOS are investigated via a newly formulated Hamiltonian (does not include BCS type Hamiltonian that includes the effects of electron-phonon, anharmonicities and that of isotopic impurities. The automatic appearance of pairons, temperature, impurity and electron-phonon coupling of renormalized frequencies, widths, shifts and PDOS emerges as a characteristic feature of present theory. The numerical investigations on PDOS for the YBa2Cu3O7 − δ crystal predicts several new feature of high temperature superconductors (HTS and agreements with experimental observations.

  8. String theory as a quantum theory of gravity

    International Nuclear Information System (INIS)

    Horowitz, G.T.

    1990-01-01

    First, the connection between string theory and gravity is discussed - at first sight the theory of strings seem to have nothing to do with gravity but an intimate connection is shown. Then the quantum perturbation expansion is discussed. Thirdly, string theory is considered as a classical theory of gravity and finally recent speculation about a phase of string theory which is independent of a spacetime metric is discussed. (author)

  9. Number theory via Representation theory

    Indian Academy of Sciences (India)

    2014-11-09

    Number theory via Representation theory. Eknath Ghate. November 9, 2014. Eightieth Annual Meeting, Chennai. Indian Academy of Sciences1. 1. This is a non-technical 20 minute talk intended for a general Academy audience.

  10. K-theory and representation theory

    International Nuclear Information System (INIS)

    Kuku, A.O.

    2003-01-01

    This contribution includes K-theory of orders, group-rings and modules over EI categories, equivariant higher algebraic K-theory for finite, profinite and compact Lie group actions together with their relative generalisations and applications

  11. Sensation of Cold during the Ice Water Test Corresponds to the Perception of Pain during Botulinum Toxin Bladder Wall Injections.

    Science.gov (United States)

    Reitz, André; Hüsch, Tanja; Doggweiler, Regula; Buse, Stephan; Haferkamp, Axel

    2018-01-01

    To investigate the association of bladder cold sensation (BCS) during the ice water test (IWT) and pain perception when botulinum toxin injections (BTI) are administered into the bladder wall. In 86 patients with idiopathic overactive bladder, the BCS during the IWT was investigated. Patients were divided into 2 groups: with and without BCS. During subsequent administration of BTI, the number of perceived and painful injections as well as the pain levels on a 0-100 pain scale were compared in both groups using Student t test. Thirty-five patients reported a BCS, while 51 did not. After 10 BTI, the mean number of perceived injections was 7.9 in patients with and 2.4 in patients without BCS (p sensation (p perceptions of cold and pain in the urinary bladder may use similar receptors and neuronal pathways. © 2018 S. Karger AG, Basel.

  12. A 20MeV (p,d) study of nuclear structure in the even and odd tin isotopes

    International Nuclear Information System (INIS)

    Fleming, D.G.; Paris-11 Univ., 91 - Orsay

    1978-01-01

    The even and odd tin isotopes have been studied by 20 MeV (p,d) reactions. States strongly populated in the odd isotopes are due to the valence neutron shells and extend up to only 2 MeV of excitation energy; 'deep hole' states were not identified. The occupation probabilities extracted from finite-range distorted-wave-Born-approximation calculations generally agree well with the predictions of the BCS theory of superconducting nuclei, particularly with the calculations of Clement and Baranger. In the even tin isotopes, strongly populated states are characterized predominantly by L=2 transfers extending up to 4 MeV excitation energy. The experimental spectroscopic factors are compared with the BCS calculated values of Clement and Baranger, Alzetta and Sawicki, and Van Gunsteren; relatively good agreement is obtained for L=2 transitions, but not for L=0 transitions. A considerable fraction of the sum rule L=2 strength in 118 Sn is missing in the 119 Sn(p,d) 118 Sn experimental spectrum; in like manner, no 4 + strength could be identified in either 114 Sn or 118 Sn

  13. Biliary Cast Syndrome: Hepatic Artery Resistance Index, Pathological Changes, Morphology and Endoscopic Therapy

    Directory of Open Access Journals (Sweden)

    Hu Tian

    2015-01-01

    Full Text Available Background: Biliary cast syndrome (BCS was a postoperative complication of orthotopic liver transplantation (OLT, and the reason for BSC was considered to relate with ischemic type biliary lesions. This study aimed to evaluate the relationship between BCS following OLT and the hepatic artery resistance index (HARI, and to observe pathological changes and morphology of biliary casts. Methods: Totally, 18 patients were diagnosed with BCS by cholangiography following OLT using choledochoscope or endoscopic retrograde cholangiopancreatography. In addition, 36 patients who did not present with BCS in the corresponding period had detectable postoperative HARI on weeks 1, 2, 3 shown by color Doppler flow imaging. The compositions of biliary casts were analyzed by pathological examination and scanning electron microscopy. Results: HARI values of the BCS group were significantly decreased as compared with the non-BCS group on postoperative weeks 2 and 3 (P 1 (OR = 1.300; 1.223; and 1.889, respectively. The OR of HARI 3 was statistically significant (OR = 1.889; 95% confidence interval = 1.166-7.490; P = 0.024. The compositions of biliary casts were different when bile duct stones were present. Furthermore, vascular epithelial cells were found by pathological examination in biliary casts. Conclusions: HARI may possibly serve as an independent risk factor and early predictive factor of BCS. Components and formation of biliary casts and bile duct stones are different.

  14. Can you estimate body composition in dogs from photographs?

    Science.gov (United States)

    Gant, Poppy; Holden, Shelley L; Biourge, Vincent; German, Alexander J

    2016-01-20

    A validated method for assessing the visual characteristics of body condition from photographs (vBCS), would be a useful initial screening tool for client-owned dogs. In this retrospective study, photographs taken before and after weight loss from 155 overweight and obese dogs attending a weight management referral clinic were used in designing and testing the feasibility of vBCS. Observers with a range of experience examined the photographs, and estimated body condition indirectly (vBCS) using three different methods. In the first method (vBCSmeasured), the ratio of abdominal width to thoracic width (A:T) was measured, and cut-points used to determine body condition; the second method (iBCSsubjective) involved semi-quantitative examination using visual descriptors of BCS; the third (vBCSadjusted) was a combined approach whereby A:T ratio was first determined, and the final score modified if necessary after assessing photographs. When an experienced observer performed vBCS, there were moderate-to-good associations between body fat (measured by dual-energy X-ray absorptiometry) and the three vBCS methods (median Rs: 0.51-0.75; P  0.05 for all). Compared with ideal weight and obese dogs, errors in assessing body condition were more common for overweight dogs (e.g. BCS 6-7/9, P photographs, but performance varies amongst observers.

  15. Accelerated whole-brain multi-parameter mapping using blind compressed sensing.

    Science.gov (United States)

    Bhave, Sampada; Lingala, Sajan Goud; Johnson, Casey P; Magnotta, Vincent A; Jacob, Mathews

    2016-03-01

    To introduce a blind compressed sensing (BCS) framework to accelerate multi-parameter MR mapping, and demonstrate its feasibility in high-resolution, whole-brain T1ρ and T2 mapping. BCS models the evolution of magnetization at every pixel as a sparse linear combination of bases in a dictionary. Unlike compressed sensing, the dictionary and the sparse coefficients are jointly estimated from undersampled data. Large number of non-orthogonal bases in BCS accounts for more complex signals than low rank representations. The low degree of freedom of BCS, attributed to sparse coefficients, translates to fewer artifacts at high acceleration factors (R). From 2D retrospective undersampling experiments, the mean square errors in T1ρ and T2 maps were observed to be within 0.1% up to R = 10. BCS was observed to be more robust to patient-specific motion as compared to other compressed sensing schemes and resulted in minimal degradation of parameter maps in the presence of motion. Our results suggested that BCS can provide an acceleration factor of 8 in prospective 3D imaging with reasonable reconstructions. BCS considerably reduces scan time for multiparameter mapping of the whole brain with minimal artifacts, and is more robust to motion-induced signal changes compared to current compressed sensing and principal component analysis-based techniques. © 2015 Wiley Periodicals, Inc.

  16. Genetic relationships between body condition score and reproduction traits in Canadian Holstein and Ayrshire first-parity cows.

    Science.gov (United States)

    Bastin, C; Loker, S; Gengler, N; Sewalem, A; Miglior, F

    2010-05-01

    The objective of this study was to investigate the genetic relationship between body condition score (BCS) and reproduction traits for first-parity Canadian Ayrshire and Holstein cows. Body condition scores were collected by field staff several times over the lactation in herds from Québec, and reproduction records (including both fertility and calving traits) were extracted from the official database used for the Canadian genetic evaluation of those herds. For each breed, six 2-trait animal models were run; they included random regressions that allowed the estimation of genetic correlations between BCS over the lactation and reproduction traits that are measured as a single lactation record. Analyses were undertaken on data from 108 Ayrshire herds and 342 Holstein herds. Average daily heritabilities of BCS were close to 0.13 for both breeds; these relatively low estimates might be explained by the high variability among herds and BCS evaluators. Genetic correlations between BCS and interval fertility traits (days from calving to first service, days from first service to conception, and days open) were negative and ranged between -0.77 and -0.58 for Ayrshire and between -0.31 and -0.03 for Holstein. Genetic correlations between BCS and 56-d nonreturn rate at first insemination were positive and moderate. The trends of these genetic correlations over the lactation suggest that a genetically low BCS in early lactation would increase the number of days that the primiparous cow was not pregnant and would decrease the chances of the primiparous cow to conceive at first service. Genetic correlations between BCS and calving traits were generally the strongest at calving and decreased with increasing days in milk. The correlation between BCS at calving and maternal calving ease was 0.21 for Holstein and 0.31 for Ayrshire and emphasized the relationship between fat cows around calving and dystocia. Genetic correlations between calving traits and BCS during the subsequent

  17. Large N field theories, string theory and gravity

    Energy Technology Data Exchange (ETDEWEB)

    Maldacena, J [Lyman Laboratory of Physics, Harvard University, Cambridge (United States)

    2002-05-15

    We describe the holographic correspondence between field theories and string/M theory, focusing on the relation between compactifications of string/ M theory on Anti-de Sitter spaces and conformal field theories. We review the background for this correspondence and discuss its motivations and the evidence for its correctness. We describe the main results that have been derived from the correspondence in the regime that the field theory is approximated by classical or semiclassical gravity. We focus on the case of the N = 4 supersymmetric gauge theory in four dimensions. These lecture notes are based on the Review written by O. Aharony, S. Gubser, J. Maldacena, H. Ooguri and Y. Oz. (author)

  18. Morse theory interpretation of topological quantum field theories

    International Nuclear Information System (INIS)

    Labastida, J.M.F.

    1989-01-01

    Topological quantum field theories are interpreted as a generalized form of Morse theory. This interpretation is applied to formulate the simplest topological quantum field theory: Topological quantum mechanics. The only non-trivial topological invariant corresponding to this theory is computed and identified with the Euler characteristic. Using field theoretical methods this topological invariant is calculated in different ways and in the process a proof of the Gauss-Bonnet-Chern-Avez formula as well as some results of degenerate Morse theory are obtained. (orig.)

  19. String theory

    International Nuclear Information System (INIS)

    Chan Hongmo.

    1987-10-01

    The paper traces the development of the String Theory, and was presented at Professor Sir Rudolf Peierls' 80sup(th) Birthday Symposium. The String theory is discussed with respect to the interaction of strings, the inclusion of both gauge theory and gravitation, inconsistencies in the theory, and the role of space-time. The physical principles underlying string theory are also outlined. (U.K.)

  20. Gravity, general relativity theory and alternative theories

    International Nuclear Information System (INIS)

    Zel'dovich, Ya.B.; Grishchuk, L.P.; Moskovskij Gosudarstvennyj Univ.

    1986-01-01

    The main steps in plotting the current gravitation theory and some prospects of its subsequent development are reviewed. The attention is concentrated on a comparison of the relativistic gravitational field with other physical fields. Two equivalent formulations of the general relativity (GR) - geometrical and field-theoretical - are considered in detail. It is shown that some theories of gravity constructed as the field theories at a flat background space-time are in fact just different formulations of GR and not alternative theories

  1. Primary Budd-Chiari syndrome - a single center experience.

    Science.gov (United States)

    Raszeja-Wyszomirska, Joanna; Mieżyńska-Kurtycz, Joanna; Marlicz, Wojciech; Lawniczak, Małgorzata; Wójcicki, Maciej

    2012-09-01

    Budd-Chiari syndrome (BCS) is recognized as a clinical manifestation of various prothrombotic conditions which may be lethal within 3 years of the onset of symptoms if untreated. This study is a retrospective analysis of patients with BCS managed between 2004 and 2011. The diagnosis was confirmed with contrast CT-angiography and/or Doppler ultrasound. BCS was diagnosed in 20 patients (11 females and 9 males), median age 38 years (ranging from 18 to 56). Twelve patients were referred as acute BCS for the liver transplant (LTx) assessment. Thrombosis of the hepatic veins was caused by myeloproliferative disorders (n=8), end-stage liver disease (n=4), protein C deficiency (n=3), paroxysmal nocturnal hemoglobinuria (PNH) (n=1), antiphospholipid syndrome (n=1) and secondary poliglobulia (n=1). In two patients the origin of BCS could not be established despite appropriate screening. Median follow-up was 29 months. Low molecular heparin with subsequent conversion to vitamin K antagonists was routinely applied in all patients. Two patients underwent TIPS procedure with good long term outcome and 10 subjects received LTx; 1 patient was lost to follow-up and 1 died of chest infection 9 years since the diagnosis of BCS was made; 14 patients, including those who received LTx, were alive and well at least one year after BCS diagnosis. All survivors remain stable and are followed-up on a regular basis. Strict adherence to the diagnostic and therapeutic guidelines plays a crucial role in the management of BCS patients. Our results confirm the efficacy of anticoagulation as well as TIPS and/or OLT in treatment of this rare condition.

  2. Theory X and Theory Y in the Organizational Structure.

    Science.gov (United States)

    Barry, Thomas J.

    This document defines contrasting assumptions about the labor force--theory X and theory Y--and shows how they apply to the pyramid organizational structure, examines the assumptions of the two theories, and finally, based on a survey and individual interviews, proposes a merger of theories X and Y to produce theory Z. Organizational structures…

  3. Layered SmBaCuCoO5+δ and SmBaCuFeO5+δ perovskite oxides as cathode materials for proton-conducting SOFCs

    International Nuclear Information System (INIS)

    Nian Qiong; Zhao Ling; He Beibei; Lin Bin; Peng Ranran; Meng Guangyao; Liu Xingqin

    2010-01-01

    A dense BaCe 0.8 Sm 0.2 O 5+δ (BCS) electrolyte was fabricated on a porous anode by in situ drop-coating to develop a simple and cost-effective route to fabricate proton-conducting solid oxide fuel cells (SOFCs). Layered perovskite-structure oxides SmBaCuCoO 5+δ (SBCC) and SmBaCuFeO 5+δ (SBCF) were prepared and the electrical conductivity, the thermal expansion coefficient and electrochemical performance were investigated as potential cathode materials for proton-conducting SOFCs. Thermal expansion coefficients of SBCC and SBCF were suitable for BCS electrolyte and the electrical conductivity of the SBCC is higher than that of the SBCF. The maximum power density of 449 mW cm 2 and 333 mW cm 2 at 700 o C were obtained for the SBCC/BCS/NiO-BCS and SBCF/BCS/NiO-BCS cells, respectively. The interfacial polarization resistances for SBCC and SBCF cathode are as low as 0.137 Ω cm -2 and 0.196 Ω cm -2 at 700 o C, respectively. The results indicate that the SBCC and SBCF are promising cathode materials for proton-conducting SOFCs.

  4. Evolution of accesses to information on breast cancer and screening on the Brazilian National Cancer Institute website: an exploratory study.

    Science.gov (United States)

    Vasconcellos-Silva, Paulo Roberto; Sormunen, Taina; Craftman, Åsa Gransjön

    2018-04-01

    Delays in diagnosis due to low Breast Cancer awareness are widespread in Brazil maybe owing to ineffective strategies to raise attention on early diagnosis. As a proxy of collective interest in BC screanning (BCS) we studied the monthly accesses to BC and BCS webpages in INCA's website along 48 months. A log analyzer built a time serie (2006-2009) of BC and BCS monthly means, which oscilations were studied by analysis of variance (ANOVA). We found significant increasing accesses to BC and transient "attention peaks". Enlargement in BC/BCS differences along all period were caused by increasing accesses to BC and decreasing/minor/stable oscillations to SBC pages. These results are consistent with previous reports on increasing interest to BC contrasting with indifference on BCS. In the context of an exploratory study, we discussed some aspects: weakness of a "prevention culture"; lack of confidence in health system and screening programs; "celebrity effect" in the context of media framing; collective perception of risks heightened by perception of social vulnerability. Findings suggest that culture-tailored communication strategies would be necessary to inform Brazilian people about BCS. Future research is needed to study social perceptions and constructions on BC topics.

  5. Supergravity theories

    International Nuclear Information System (INIS)

    Uehara, S.

    1985-01-01

    Of all supergravity theories, the maximal, i.e., N = 8 in 4-dimension or N = 1 in 11-dimension, theory should perform the unification since it owns the highest degree of symmetry. As to the N = 1 in d = 11 theory, it has been investigated how to compactify to the d = 4 theories. From the phenomenological point of view, local SUSY GUTs, i.e., N = 1 SUSY GUTs with soft breaking terms, have been studied from various angles. The structures of extended supergravity theories are less understood than those of N = 1 supergravity theories, and matter couplings in N = 2 extended supergravity theories are under investigation. The harmonic superspace was recently proposed which may be useful to investigate the quantum effects of extended supersymmetry and supergravity theories. As to the so-called Kaluza-Klein supergravity, there is another possibility. (Mori, K.)

  6. W-007H B Plant Process Condensate Treatment Facility. Revision 3

    International Nuclear Information System (INIS)

    Rippy, G.L.

    1995-01-01

    B Plant Process Condensate (BCP) liquid effluent stream is the condensed vapors originating from the operation of the B Plant low-level liquid waste concentration system. In the past, the BCP stream was discharged into the soil column under a compliance plan which expired January 1, 1987. Currently, the BCP stream is inactive, awaiting restart of the E-23-3 Concentrator. B Plant Steam Condensate (BCS) liquid effluent stream is the spent steam condensate used to supply heat to the E-23-3 Concentrator. The tube bundles in the E-23-3 Concentrator discharge to the BCS. In the past, the BCS stream was discharged into the soil column. Currently, the BCS stream is inactive. This project shall provide liquid effluent systems (BCP/BCS/BCE) capable of operating for a minimum of 20 years, which does not include the anticipated decontamination and decommissioning (D and D) period

  7. W-007H B Plant Process Condensate Treatment Facility. Revision 3

    Energy Technology Data Exchange (ETDEWEB)

    Rippy, G.L.

    1995-01-20

    B Plant Process Condensate (BCP) liquid effluent stream is the condensed vapors originating from the operation of the B Plant low-level liquid waste concentration system. In the past, the BCP stream was discharged into the soil column under a compliance plan which expired January 1, 1987. Currently, the BCP stream is inactive, awaiting restart of the E-23-3 Concentrator. B Plant Steam Condensate (BCS) liquid effluent stream is the spent steam condensate used to supply heat to the E-23-3 Concentrator. The tube bundles in the E-23-3 Concentrator discharge to the BCS. In the past, the BCS stream was discharged into the soil column. Currently, the BCS stream is inactive. This project shall provide liquid effluent systems (BCP/BCS/BCE) capable of operating for a minimum of 20 years, which does not include the anticipated decontamination and decommissioning (D and D) period.

  8. On the interplay between string theory and field theory

    International Nuclear Information System (INIS)

    Brunner, I.

    1998-01-01

    In this thesis, we have discussed various aspects of branes in string theory and M-theory. In chapter 2 we were able to construct six-dimensional chiral interacting eld theories from Hanany-Witten like brane setups. The field theory requirement that the anomalies cancel was reproduced by RR-charge conservation in the brane setup. The data of the Hanany-Witten setup, which consists of brane positions, was mapped to instanton data. The orbifold construction can be extended to D and E type singularities. In chapter 3 we discussed a matrix conjecture, which claims that M-theory in the light cone gauge is described by the quantum mechanics of D0 branes. Toroidal compactifications of M-theory have a description in terms of super Yang-Mills theory an the dual torus. For more than three compactified dimensions, more degrees of freedom have to be added. In some sense, the philosophy in this chapter is orthogonal to the previous chapter: Here, we want to get M-theory results from eld theory considerations, whereas in the previous chapter we obtained eld theory results by embedding the theories in string theory. Our main focus was on the compactification on T 6 , which leads to complications. Here, the Matrix model is again given by an eleven dimensional theory, not by a lower dimensional field theory. Other problems and possible resolutions of Matrix theory are discussed at the end of chapter 3. In the last chapter we considered M- and F-theory compactifications on Calabi-Yau fourfolds. After explaining some basics of fourfolds, we showed that the web of fourfolds is connected by singular transitions. The two manifolds which are connected by the transition are different resolutions of the same singular manifold. The resolution of the singularities can lead to a certain type of divisors, which lead to non-perturbative superpotentials, when branes wrap them. The vacua connected by the transitions can be physically very different. (orig.)

  9. On the interplay between string theory and field theory

    Energy Technology Data Exchange (ETDEWEB)

    Brunner, I.

    1998-07-08

    In this thesis, we have discussed various aspects of branes in string theory and M-theory. In chapter 2 we were able to construct six-dimensional chiral interacting eld theories from Hanany-Witten like brane setups. The field theory requirement that the anomalies cancel was reproduced by RR-charge conservation in the brane setup. The data of the Hanany-Witten setup, which consists of brane positions, was mapped to instanton data. The orbifold construction can be extended to D and E type singularities. In chapter 3 we discussed a matrix conjecture, which claims that M-theory in the light cone gauge is described by the quantum mechanics of D0 branes. Toroidal compactifications of M-theory have a description in terms of super Yang-Mills theory an the dual torus. For more than three compactified dimensions, more degrees of freedom have to be added. In some sense, the philosophy in this chapter is orthogonal to the previous chapter: Here, we want to get M-theory results from eld theory considerations, whereas in the previous chapter we obtained eld theory results by embedding the theories in string theory. Our main focus was on the compactification on T{sup 6}, which leads to complications. Here, the Matrix model is again given by an eleven dimensional theory, not by a lower dimensional field theory. Other problems and possible resolutions of Matrix theory are discussed at the end of chapter 3. In the last chapter we considered M- and F-theory compactifications on Calabi-Yau fourfolds. After explaining some basics of fourfolds, we showed that the web of fourfolds is connected by singular transitions. The two manifolds which are connected by the transition are different resolutions of the same singular manifold. The resolution of the singularities can lead to a certain type of divisors, which lead to non-perturbative superpotentials, when branes wrap them. The vacua connected by the transitions can be physically very different. (orig.)

  10. High-T{sub c} cuprate superconductivity in a nutshell

    Energy Technology Data Exchange (ETDEWEB)

    Won, Hyekyung [Department of Physics, Hallym University, Chuncheon 200-702 (Korea); Haas, Stephan; Parker, David; Maki, Kazumi [Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089-0484 (United States)

    2005-02-01

    Since the discovery of high-T{sub c} cuprate superconductivity in 1986 many new experimental techniques and theoretical concepts have been developed. In particular it was shown that the BCS theory of d-wave superconductivity describes semi-quantitatively the high-T{sub c} superconductivity. Furthermore, it was demonstrated that Volovik's approach is extremely useful for finding the quasiparticle properties in the vortex state. Here we survey these developments and forecast future directions. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  11. Some Recent Progress on Quark Pairings in Dense Quark and Nuclear Matter

    International Nuclear Information System (INIS)

    Pang Jinyi; Wang Jincheng; Wang Qun

    2012-01-01

    In this review article we give a brief overview on some recent progress in quark pairings in dense quark/nuclear matter mostly developed in the past five years. We focus on following aspects in particular: the BCS-BEC crossover in the CSC phase, the baryon formation and dissociation in dense quark/nuclear matter, the Ginzburg-Landau theory for three-flavor dense matter with U A (1) anomaly, and the collective and Nambu-Goldstone modes for the spin-one CSC. (physics of elementary particles and fields)

  12. When is a theory a theory? A case example.

    Science.gov (United States)

    Alkin, Marvin C

    2017-08-01

    This discussion comments on the approximately 20years history of writings on the prescriptive theory called Empowerment Evaluation. To do so, involves examining how "Empowerment Evaluation Theory" has been defined at various points of time (particularly 1996 and now in 2015). Defining a theory is different from judging the success of a theory. This latter topic has been addressed elsewhere by Michael Scriven, Michael Patton, and Brad Cousins. I am initially guided by the work of Robin Miller (2010) who has written on the issue of how to judge the success of a theory. In doing so, she provided potential standards for judging the adequacy of theories. My task is not judging the adequacy or success of the Empowerment Evaluation prescriptive theory in practice, but determining how well the theory is delineated. That is, to what extent do the writings qualify as a prescriptive theory. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Superstring theory

    International Nuclear Information System (INIS)

    Schwarz, J.H.

    1985-01-01

    Dual string theories, initially developed as phenomenological models of hadrons, now appear more promising as candidates for a unified theory of fundamental interactions. Type I superstring theory (SST I), is a ten-dimensional theory of interacting open and closed strings, with one supersymmetry, that is free from ghosts and tachyons. It requires that an SO(eta) or Sp(2eta) gauge group be used. A light-cone-gauge string action with space-time supersymmetry automatically incorporates the superstring restrictions and leads to the discovery of type II superstring theory (SST II). SST II is an interacting theory of closed strings only, with two D=10 supersymmetries, that is also free from ghosts and tachyons. By taking six of the spatial dimensions to form a compact space, it becomes possible to reconcile the models with our four-dimensional perception of spacetime and to define low-energy limits in which SST I reduces to N=4, D=4 super Yang-Mills theory and SST II reduces to N=8, D=4 supergravity theory. The superstring theories can be described by a light-cone-gauge action principle based on fields that are functionals of string coordinates. With this formalism any physical quantity should be calculable. There is some evidence that, unlike any conventional field theory, the superstring theories provide perturbatively renormalizable (SST I) or finite (SST II) unifications of gravity with other interactions

  14. Abelian gauge symmetries in F-theory and dual theories

    Science.gov (United States)

    Song, Peng

    In this dissertation, we focus on important physical and mathematical aspects, especially abelian gauge symmetries, of F-theory compactifications and its dual formulations within type IIB and heterotic string theory. F-theory is a non-perturbative formulation of type IIB string theory which enjoys important dualities with other string theories such as M-theory and E8 x E8 heterotic string theory. One of the main strengths of F-theory is its geometrization of many physical problems in the dual string theories. In particular, its study requires a lot of mathematical tools such as advanced techniques in algebraic geometry. Thus, it has also received a lot of interests among mathematicians, and is a vivid area of research within both the physics and the mathematics community. Although F-theory has been a long-standing theory, abelian gauge symmetry in Ftheory has been rarely studied, until recently. Within the mathematics community, in 2009, Grassi and Perduca first discovered the possibility of constructing elliptically fibered varieties with non-trivial toric Mordell-Weil group. In the physics community, in 2012, Morrison and Park first made a major advancement by constructing general F-theory compactifications with U(1) abelian gauge symmetry. They found that in such cases, the elliptically-fibered Calabi-Yau manifold that F-theory needs to be compactified on has its fiber being a generic elliptic curve in the blow-up of the weighted projective space P(1;1;2) at one point. Subsequent developments have been made by Cvetic, Klevers and Piragua extended the works of Morrison and Park and constructed general F-theory compactifications with U(1) x U(1) abelian gauge symmetry. They found that in the U(1) x U(1) abelian gauge symmetry case, the elliptically-fibered Calabi-Yau manifold that F-theory needs to be compactified on has its fiber being a generic elliptic curve in the del Pezzo surface dP2. In chapter 2 of this dissertation, I bring this a step further by

  15. F-theory and 2d (0,2) theories

    Energy Technology Data Exchange (ETDEWEB)

    Schäfer-Nameki, Sakura [Department of Mathematics, King’s College London, The Strand, London WC2R 2LS (United Kingdom); Weigand, Timo [Institut für Theoretische Physik, Ruprecht-Karls-Universität,Philosophenweg 19, 69120 Heidelberg (Germany)

    2016-05-11

    F-theory compactified on singular, elliptically fibered Calabi-Yau five-folds gives rise to two-dimensional gauge theories preserving N=(0,2) supersymmetry. In this paper we initiate the study of such compactifications and determine the dictionary between the geometric data of the elliptic fibration and the 2d gauge theory such as the matter content in terms of (0,2) superfields and their supersymmetric couplings. We study this setup both from a gauge-theoretic point of view, in terms of the partially twisted 7-brane theory, and provide a global geometric description based on the structure of the elliptic fibration and its singularities. Global consistency conditions are determined and checked against the dual M-theory compactification to one dimension. This includes a discussion of gauge anomalies, the structure of the Green-Schwarz terms and the Chern-Simons couplings in the dual M-theory supersymmetric quantum mechanics. Furthermore, by interpreting the resulting 2d (0,2) theories as heterotic worldsheet theories, we propose a correspondence between the geometric data of elliptically fibered Calabi-Yau five-folds and the target space of a heterotic gauged linear sigma-model (GLSM). In particular the correspondence between the Landau-Ginsburg and sigma-model phase of a 2d (0,2) GLSM is realized via different T-branes or gluing data in F-theory.

  16. Mechanistic analysis of solute transport in an in vitro physiological two-phase dissolution apparatus.

    Science.gov (United States)

    Mudie, Deanna M; Shi, Yi; Ping, Haili; Gao, Ping; Amidon, Gordon L; Amidon, Gregory E

    2012-10-01

    In vitro dissolution methodologies that adequately capture the oral bioperformance of solid dosage forms are critical tools needed to aid formulation development. Such methodologies must encompass important physiological parameters and be designed with drug properties in mind. Two-phase dissolution apparatuses, which contain an aqueous phase in which the drug dissolves (representing the dissolution/solubility component) and an organic phase into which the drug partitions (representing the absorption component), have the potential to provide meaningful predictions of in vivo oral bioperformance for some BCS II, and possibly some BCS IV drug products. Before such an apparatus can be evaluated properly, it is important to understand the kinetics of drug substance partitioning from the aqueous to the organic medium. A mass transport analysis was performed of the kinetics of partitioning of drug substance solutions from the aqueous to the organic phase of a two-phase dissolution apparatus. Major assumptions include pseudo-steady-state conditions, a dilute aqueous solution and diffusion-controlled transport. Input parameters can be measured or estimated a priori. This paper presents the theory and derivation of our analysis, compares it with a recent kinetic approach, and demonstrates its effectiveness in predicting in vitro partitioning profiles of three BCS II weak acids in four different in vitro two-phase dissolution apparatuses. Very importantly, the paper discusses how a two-phase apparatus can be scaled to reflect in vivo absorption kinetics and for which drug substances the two-phase dissolution systems may be appropriate tools for measuring oral bioperformance. Copyright © 2012 John Wiley & Sons, Ltd.

  17. New world of Gossamer superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Maki, Kazumi; Haas, Stephan; Parker, David [Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089-0484 (United States); Won, Hyekyung [Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Str. 38, 01187, Dresden (Germany); Department of Physics, Hallym University, Chuncheon 200-702 (Korea); Dora, Balazs; Virosztek, Attila [Department of Physics, Budapest University of Technology and Economics, 1521 Budapest (Hungary)

    2006-09-15

    Since the discovery of the high-T {sub c} cuprate superconductor La{sub 2-x}BaCuO{sub 4} in 1986 by Bednorz and Mueller, controversy regarding the nature or origin of this remarkable superconductivity has continued. However, d-wave superconductivity in the hole-doped cuprates, arising due to the anti-paramagnon exchange, was established around 1994. More recently we have shown that the mean field theory, like the BCS theory of superconductivity and Landau's Fermi liquid theory are adequate to describe the cuprates. The keys for this development are the facts that a) the pseudogap phase is d-wave density wave (dDW) and that the high-T{sub c} cuprate superconductivity is gossamer (i.e. it exists in the presence of dDW). (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Influence of body condition score on live and carcass value of cull beef cows.

    Science.gov (United States)

    Apple, J K

    1999-10-01

    Mature beef cows (n = 88) were slaughtered to determine the influence of body condition score (BCS) on carcass and live animal value. Cows were weighed and assigned a BCS (9-point scale), 24 h before slaughter. Hide and by-products weights were recorded during harvest. After a 48-h chill period, the right side of each carcass was fabricated into boneless subprimal cuts, minor cuts, lean trim, fat, and bone. Weights were recorded at all stages of fabrication. Carcass values (U.S.$/100 kg of hot carcass weight) were calculated for U.S. Utility and U.S. Cutter grades, as well as for the Utility/Cutter mix for each BCS. Gross value included the carcass value and the value of the hide and byproducts, whereas net value was calculated after harvest and fabrication costs and by-product value were considered. Live value (U.S.$/100 kg of live weight) was computed by dividing the net value by the animal's live weight 24 h before harvest. The value of the hide and by-products for BCS-2 cows was greater (Pmix, cows designated with a BCS of 7 and 8 had greater (P.05) to BCS-7 cows. Information from this study can be used by the non-fed beef industry to establish a value-based marketing system. Data from this study would indicate that marketing cull beef cows at a BCS of 6 could optimize economic returns to both cow-calf producers and non-fed beef packers.

  19. Breast cancer screening among shift workers: a nationwide population-based survey in Korea.

    Science.gov (United States)

    Son, Heesook; Kang, Youngmi

    2017-04-01

    We aimed to examine the association between shift work types and participation in breast cancer screening (BCS) programs by comparing rates of participation for BCS among regular daytime workers and alternative shift workers using data from a nationally representative, population-based survey conducted in Korea. In addition, the results were analyzed according to sociodemographic factors, including occupation, education, income, private health insurance, age, and number of working hours a week. This secondary cross-sectional analysis used data from the 2012 Korean National Health and Nutritional Examination Survey. The target population included women aged ≥ 40 years who responded as to whether they had undergone BCS in the previous year. Accordingly, we analyzed survey data for a total of 1,193 women and used a multivariate logistic regression analysis to evaluate the differences in factors affecting BCS between regular daytime and alternative shift workers. A logistic regression analysis was performed considering private health insurance as a significant sociodemographic factor for BCS among regular daytime shift workers. In contrast, none of the tested variables could significantly predict adherence to BCS among alternative shift workers. The results of this study suggest the need for the development of comprehensive workplace breast cancer prevention programs by considering shift work types. More attention should be given to female workers with low education levels, those who are uninsured, and young workers to improve the participation rate for BCS at the workplace.

  20. Reproductive responses and progesterone levels of postpartum oestrus synchronization in goats with different body reserves

    Directory of Open Access Journals (Sweden)

    Fabiana V. Rodrigues

    2011-10-01

    Full Text Available Thirty adult goats were classified at parturition into two body condition score (BCS groups: BCI (n=16 with a score of 2.7 and BCII (n=14 with a score of 2.0. On the fiftieth day postpartum, oestrus was synchronized by CIDR for 5 days. Upon CIDR removal (Day 0, they received 1 mL of PGF2α IM and mated for 72 hours. Kids were kept with does and weaned at 40 days of age. Blood samples were taken at 0, 1, 4, 8 and 21 days after CIDR removal for progesterone assay. The BCI group showed a greater weight loss compared to the BCII group, and BCS before synchronization was 1.9±0.08 and 1.6±0.07 for the BCI and BCII groups, respectively (Pvs 36%; Pvs 1.25; Pvs 0.25; P<0.05. Progesterone concentration was higher in pregnant does in BCI. A positive relationship was found between progesterone level at CIDR removal and BCS at parturition (0.57; P<0.01, also between progesterone level at 21 days after CIDR removal and BCS at parturition (0.47; P<0.05, or BCS before synchronization (0.51; P<0.05. We conclude that oestrus response to postpartum CIDR synchronization appeared to be slightly dependent on BCS. However, goats with low BCS at oestrus synchronization exhibited a reduction in pregnancy rate.

  1. Relationships between fertility and postpartum changes in body condition and body weight in lactating dairy cows.

    Science.gov (United States)

    Carvalho, P D; Souza, A H; Amundson, M C; Hackbart, K S; Fuenzalida, M J; Herlihy, M M; Ayres, H; Dresch, A R; Vieira, L M; Guenther, J N; Grummer, R R; Fricke, P M; Shaver, R D; Wiltbank, M C

    2014-01-01

    The relationship between energy status and fertility in dairy cattle was retrospectively analyzed by comparing fertility with body condition score (BCS) near artificial insemination (AI; experiment 1), early postpartum changes in BCS (experiment 2), and postpartum changes in body weight (BW; experiment 3). To reduce the effect of cyclicity status, all cows were synchronized with Double-Ovsynch protocol before timed AI. In experiment 1, BCS of lactating dairy cows (n = 1,103) was evaluated near AI. Most cows (93%) were cycling at initiation of the breeding Ovsynch protocol (first GnRH injection). A lower percentage pregnant to AI (P/AI) was found in cows with lower (≤ 2.50) versus higher (≥ 2.75) BCS (40.4 vs. 49.2%). In experiment 2, lactating dairy cows on 2 commercial dairies (n = 1,887) were divided by BCS change from calving until the third week postpartum. Overall, P/AI at 70-d pregnancy diagnosis differed dramatically by BCS change and was least for cows that lost BCS, intermediate for cows that maintained BCS, and greatest for cows that gained BCS [22.8% (180/789), 36.0% (243/675), and 78.3% (331/423), respectively]. Surprisingly, a difference existed between farms with BCS change dramatically affecting P/AI on one farm and no effect on the other farm. In experiment 3, lactating dairy cows (n = 71) had BW measured weekly from the first to ninth week postpartum and then had superovulation induced using a modified Double-Ovsynch protocol. Cows were divided into quartiles (Q) by percentage of BW change (Q1 = least change; Q4 = most change) from calving until the third week postpartum. No effect was detected of quartile on number of ovulations, total embryos collected, or percentage of oocytes that were fertilized; however, the percentage of fertilized oocytes that were transferable embryos was greater for cows in Q1, Q2, and Q3 than Q4 (83.8, 75.2, 82.6, and 53.2%, respectively). In addition, percentage of degenerated embryos was least for cows in Q1, Q2

  2. Relationships between fertility and postpartum changes in body condition and body weight in lactating dairy cows

    Science.gov (United States)

    Carvalho, P. D.; Souza, A. H.; Amundson, M. C.; Hackbart, K. S.; Fuenzalida, M. J.; Herlihy, M. M.; Ayres, H.; Dresch, A. R.; Vieira, L. M.; Guenther, J. N.; Grummer, R. R.; Fricke, P. M.; Shaver, R. D.; Wiltbank, M. C.

    2018-01-01

    The relationship between energy status and fertility in dairy cattle was retrospectively analyzed by comparing fertility with body condition score (BCS) near artificial insemination (AI; experiment 1), early postpartum changes in BCS (experiment 2), and postpartum changes in body weight (BW; experiment 3). To reduce the effect of cyclicity status, all cows were synchronized with Double-Ovsynch protocol before timed AI. In experiment 1, BCS of lactating dairy cows (n = 1,103) was evaluated near AI. Most cows (93%) were cycling at initiation of the breeding Ovsynch protocol (first GnRH injection). A lower percentage pregnant to AI (P/AI) was found in cows with lower (≤2.50) versus higher (≥2.75) BCS (40.4 vs. 49.2%). In experiment 2, lactating dairy cows on 2 commercial dairies (n = 1,887) were divided by BCS change from calving until the third week postpartum. Overall, P/AI at 70-d pregnancy diagnosis differed dramatically by BCS change and was least for cows that lost BCS, intermediate for cows that maintained BCS, and greatest for cows that gained BCS [22.8% (180/789), 36.0% (243/675), and 78.3% (331/423), respectively]. Surprisingly, a difference existed between farms with BCS change dramatically affecting P/AI on one farm and no effect on the other farm. In experiment 3, lactating dairy cows (n = 71) had BW measured weekly from the first to ninth week postpartum and then had superovulation induced using a modified Double-Ovsynch protocol. Cows were divided into quartiles (Q) by percentage of BW change (Q1 = least change; Q4 = most change) from calving until the third week postpartum. No effect was detected of quartile on number of ovulations, total embryos collected, or percentage of oocytes that were fertilized; however, the percentage of fertilized oocytes that were transferable embryos was greater for cows in Q1, Q2, and Q3 than Q4 (83.8, 75.2, 82.6, and 53.2%, respectively). In addition, percentage of degenerated embryos was least for cows in Q1, Q2, and

  3. Strings - Links between conformal field theory, gauge theory and gravity

    International Nuclear Information System (INIS)

    Troost, J.

    2009-05-01

    String theory is a candidate framework for unifying the gauge theories of interacting elementary particles with a quantum theory of gravity. The last years we have made considerable progress in understanding non-perturbative aspects of string theory, and in bringing string theory closer to experiment, via the search for the Standard Model within string theory, but also via phenomenological models inspired by the physics of strings. Despite these advances, many deep problems remain, amongst which a non-perturbative definition of string theory, a better understanding of holography, and the cosmological constant problem. My research has concentrated on various theoretical aspects of quantum theories of gravity, including holography, black holes physics and cosmology. In this Habilitation thesis I have laid bare many more links between conformal field theory, gauge theory and gravity. Most contributions were motivated by string theory, like the analysis of supersymmetry preserving states in compactified gauge theories and their relation to affine algebras, time-dependent aspects of the holographic map between quantum gravity in anti-de-Sitter space and conformal field theories in the bulk, the direct quantization of strings on black hole backgrounds, the embedding of the no-boundary proposal for a wave-function of the universe in string theory, a non-rational Verlinde formula and the construction of non-geometric solutions to supergravity

  4. Investigations in gauge theories, topological solitons and string theories

    International Nuclear Information System (INIS)

    1993-01-01

    This is the Final Report on a supported research project on theoretical particle physics entitled ''Investigations in Gauge Theories, Topological Solitons and String Theories.'' The major theme of particle theory pursued has been within the rubric of the standard model, particularly on the interplay between symmetries and dynamics. Thus, the research has been carried out primarily in the context of gauge with or without chiral fermions and in effective chiral lagrangian field theories. The topics studied include the physical implications of abelian and non-abelian anomalies on the spectrum and possible dynamical symmetry breaking in a wide range of theories. A wide range of techniques of group theory, differential geometry and function theory have been applied to probe topological and conformal properties of quantum field theories in two and higher dimensions, the breaking of global chiral symmetries by vector-like gauge theories such as QCD,the phenomenology of a possibly strongly interacting Higgs sector within the minimal standard model, and the relevance of solitonic ideas to non-perturbative phenomena at SSC energies

  5. String field theory

    International Nuclear Information System (INIS)

    Kaku, M.

    1987-01-01

    In this article, the authors summarize the rapid progress in constructing string field theory actions, such as the development of the covariant BRST theory. They also present the newer geometric formulation of string field theory, from which the BRST theory and the older light cone theory can be derived from first principles. This geometric formulation allows us to derive the complete field theory of strings from two geometric principles, in the same way that general relativity and Yang-Mills theory can be derived from two principles based on global and local symmetry. The geometric formalism therefore reduces string field theory to a problem of finding an invariant under a new local gauge group they call the universal string group (USG). Thus, string field theory is the gauge theory of the universal string group in much the same way that Yang-Mills theory is the gauge theory of SU(N). The geometric formulation places superstring theory on the same rigorous group theoretical level as general relativity and gauge theory

  6. Impact of a PV system interconnected to the electric network of a High Consumption Domestic user's demand in BCS; Impacto de un sistema fotovoltaico interconectado a red en la demanda electrica de un usuario DAC en BCS

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez Grajales, H. R.; Agredano Diaz, Jaime; Gonzalez Galarza, R.; Munguia del Rio, G. [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2010-11-15

    forma de produccion de electricidad es al dia de hoy una opcion bastante madura, en razon de los beneficios que esta modalidad de produccion de electricidad aporta tanto al usuario como a la red electrica. En Mexico cada vez son mas los usuarios del servicio electrico que se ven motivados a invertir en este tipo de sistemas. En este articulo se analiza el caso particular de un usuario de tarifa DAC (Demanda de Alto Consumo) en la ciudad de La Paz, Baja California Sur (BCS), quien cuenta con un SFVI monofasico de 6 kWp instalado en el techo de su casa. Los resultados que se reportan provienen de datos obtenidos por el IIE durante un periodo de monitoreo de tres anos de la operacion del sistema. Los resultados incluyen informacion climatologica, balances de energia y potencia, potencias maximas, produccion y perdidas normalizadas, eficiencia del generador fotovoltaico y de los inversores; entre otros indices de desempeno. El documento resalta el impacto que tiene el SFVI sobre el consumo electrico en el inmueble y en el monto de la factura que el usuario finalmente paga a la compania suministradora del servicio electrico.

  7. Yang-Mills theory - a string theory in disguise

    International Nuclear Information System (INIS)

    Foerster, D.

    1979-01-01

    An examination of the Schwinger-Dyson equations of U(N) lattice Yang-Mills theory shows that this theory is exactly equivalent to a theory of strings that interact with one another only through their topology. (Auth.)

  8. Singularity theory and N = 2 superconformal field theories

    International Nuclear Information System (INIS)

    Warner, N.P.

    1989-01-01

    The N = 2 superconformal field theories that appear at the fixed points of the renormalization group flows of Landau-Ginsburg models are discussed. Some of the techniques of singularity theory are employed to deduce properties of these superconformal theories. These ideas are then used to deduce the relationship between Calabi-Yau compactifications and tensored discrete series models. The chiral rings of general N = 2 superconformal theories are also described. 14 refs

  9. Game theory

    DEFF Research Database (Denmark)

    Hendricks, Vincent F.

    Game Theory is a collection of short interviews based on 5 questions presented to some of the most influential and prominent scholars in game theory. We hear their views on game theory, its aim, scope, use, the future direction of game theory and how their work fits in these respects....

  10. Identity theory and personality theory: mutual relevance.

    Science.gov (United States)

    Stryker, Sheldon

    2007-12-01

    Some personality psychologists have found a structural symbolic interactionist frame and identity theory relevant to their work. This frame and theory, developed in sociology, are first reviewed. Emphasized in the review are a multiple identity conception of self, identities as internalized expectations derived from roles embedded in organized networks of social interaction, and a view of social structures as facilitators in bringing people into networks or constraints in keeping them out, subsequently, attention turns to a discussion of the mutual relevance of structural symbolic interactionism/identity theory and personality theory, looking to extensions of the current literature on these topics.

  11. Ring Theory

    CERN Document Server

    Jara, Pascual; Torrecillas, Blas

    1988-01-01

    The papers in this proceedings volume are selected research papers in different areas of ring theory, including graded rings, differential operator rings, K-theory of noetherian rings, torsion theory, regular rings, cohomology of algebras, local cohomology of noncommutative rings. The book will be important for mathematicians active in research in ring theory.

  12. Cohomological gauge theory, quiver matrix models and Donaldson-Thomas theoryCohomological gauge theory, quiver matrix models and Donaldson-Thomas theory

    NARCIS (Netherlands)

    Cirafici, M.; Sinkovics, A.; Szabo, R.J.

    2009-01-01

    We study the relation between Donaldson–Thomas theory of Calabi–Yau threefolds and a six-dimensional topological Yang–Mills theory. Our main example is the topological U(N) gauge theory on flat space in its Coulomb branch. To evaluate its partition function we use equivariant localization techniques

  13. Long-Term Follow-Up After Successful Transjugular Intrahepatic Portosystemic Shunt Placement in a Pediatric Patient with Budd-Chiari Syndrome

    International Nuclear Information System (INIS)

    Carnevale, Francisco Cesar; Szejnfeld, Denis; Moreira, Airton Mota; Gibelli, Nelson; Gregorio, Miguel Angel De; Tannuri, Uenis; Cerri, Giovanni Guido

    2008-01-01

    Orthotopic liver transplantation is the standard of care in patients with Budd-Chiari syndrome (BCS), and transjugular intrahepatic portosystemic shunt (TIPS) has become an important adjunct procedure while the patient is waiting for a liver. No long-term follow up of TIPS in BCS patients has been published in children. We report successful 10-year follow-up of a child with BCS and iatrogenic TIPS dysfunction caused by oral contraceptive use.

  14. BIOPHARMACEUTICS CLASSIFICATION SYSTEM: A STRATEGIC TOOL FOR CLASSIFYING DRUG SUBSTANCES

    OpenAIRE

    Rohilla Seema; Rohilla Ankur; Marwaha RK; Nanda Arun

    2011-01-01

    The biopharmaceutical classification system (BCS) is a scientific approach for classifying drug substances based on their dose/solubility ratio and intestinal permeability. The BCS has been developed to allow prediction of in vivo pharmacokinetic performance of drug products from measurements of permeability and solubility. Moreover, the drugs can be categorized into four classes of BCS on the basis of permeability and solubility namely; high permeability high solubility, high permeability lo...

  15. In vitro behaviors of rat mesenchymal stem cells on bacterial celluloses with different moduli

    International Nuclear Information System (INIS)

    Taokaew, Siriporn; Phisalaphong, Muenduen; Zhang Newby, Bi-min

    2014-01-01

    Compressive moduli of bacteria-synthesized cellulose (BC) were altered by two drying techniques: ambient-air drying and freeze drying. While no significant differences in dry weight were found, their cross-sectional structures and thickness varied greatly. Freeze dried BCs had loose cross-sectional structures and a thickness of ∼ 4.7 mm, whereas air dried BCs had more compacted cross-sectional structures and a thickness of ∼ 0.1 mm. The compressive moduli of the rehydrated freeze dried and rehydrated air dried BCs were measured to be 21.06 ± 0.22 kPa and 90.09 ± 21.07 kPa, respectively. When rat mesenchymal stem cells (rMSCs) were seeded on these BCs, they maintained a round morphology in the first 3 days of cultivation. More spread-out morphology and considerable proliferation on freeze dried BCs were observed in 7 days, but not on air-dried BCs. The cells were further grown for 3 weeks in the absence and presence of differentiation agents. Without using any differentiation agents, no detectable differentiation was noticed for rMSCs further cultivated on both types of BC. With differentiation inducing agents, chondrogenic differentiation, visualized by histological staining, was observed in some area of the rehydrated freeze dried BCs; while osteogenic differentiation was noticed on the stiffer rehydrated air dried BCs. - Graphical abstract: In the presence of induction agents, rat mesenchymal stem cells (rMSCs) preferentially differentiated into osteocytes on stiffer air dried BC films. - Highlights: • Bacterial cellulose (BC) sheets with different moduli generated by drying differently • Air-dried BC exhibited a modulus similar to that of bone. • Freeze-dried BC showed a modulus in the range of that of muscle. • Air-dried BC promoted the differentiation of rMSCs into osteocytes. • Freeze-dried BC promoted the differentiation of rMSCs into chondrocytes

  16. Adsorption of β-casein-surfactant mixed layers at the air-water interface evaluated by interfacial rheology.

    Science.gov (United States)

    Maestro, Armando; Kotsmar, Csaba; Javadi, Aliyar; Miller, Reinhard; Ortega, Francisco; Rubio, Ramón G

    2012-04-26

    This work presents a detailed study of the dilational viscoelastic moduli of the adsorption layers of the milk protein β-casein (BCS) and a surfactant at the liquid/air interface, over a broad frequency range. Two complementary techniques have been used: a drop profile tensiometry technique and an excited capillary wave method, ECW. Two different surfactants were studied: the nonionic dodecyldimethylphosphine oxide (C12DMPO) and the cationic dodecyltrimethylammonium bromide (DoTAB). The interfacial dilational elasticity and viscosity are very sensitive to the composition of protein-surfactant mixed adsorption layers at the air/water interface. Two different dynamic processes have been observed for the two systems studied, whose characteristic frequencies are close to 0.01 and 100 Hz. In both systems, the surface elasticity was found to show a maximum when plotted versus the surfactant concentration. However, at frequencies above 50 Hz the surface elasticity of BCS + C12DMPO is higher than the one of the aqueous BCS solution over most of the surfactant concentration range, whereas for the BCS + DoTAB it is smaller for high surfactant concentrations and higher at low concentrations. The BCS-surfactant interaction modifies the BCS random coil structure via electrostatic and/or hydrophobic interactions, leading to a competitive adsorption of the BCS-surfactant complexes with the free, unbound surfactant molecules. Increasing the surfactant concentration decreases the adsorbed proteins. However, the BCS molecules are rather strongly bound to the interface due to their large adsorption energy. The results have been fitted to the model proposed by C. Kotsmar et al. ( J. Phys. Chem. B 2009 , 113 , 103 ). Even though the model describes well the concentration dependence of the limiting elasticity, it does not properly describe its frequency dependence.

  17. Body image and quality of life in patients with and without body contouring surgery following bariatric surgery: a comparison of pre- and post-surgery groups

    Science.gov (United States)

    de Zwaan, Martina; Georgiadou, Ekaterini; Stroh, Christine E.; Teufel, Martin; Köhler, Hinrich; Tengler, Maxi; Müller, Astrid

    2014-01-01

    Background: Massive weight loss (MWL) following bariatric surgery frequently results in an excess of overstretched skin causing physical discomfort and negatively affecting quality of life, self-esteem, body image, and physical functioning. Methods: In this cross-sectional study 3 groups were compared: (1) patients prior to bariatric surgery (n = 79), (2) patients after bariatric surgery who had not undergone body contouring surgery (BCS) (n = 252), and (3) patients after bariatric surgery who underwent subsequent BCS (n = 62). All participants completed self-report questionnaires assessing body image (Multidimensional Body-Self Relations Questionnaire, MBSRQ), quality of life (IWQOL-Lite), symptoms of depression (PHQ-9), and anxiety (GAD-7). Results: Overall, 62 patients (19.2%) reported having undergone a total of 90 BCS procedures. The most common were abdominoplasties (88.7%), thigh lifts (24.2%), and breast lifts (16.1%). Post-bariatric surgery patients differed significantly in most variables from pre-bariatric surgery patients. Although there were fewer differences between patients with and without BCS, patients after BCS reported better appearance evaluation (AE), body area satisfaction (BAS), and physical functioning, even after controlling for excess weight loss and time since surgery. No differences were found for symptoms of depression and anxiety, and most other quality of life and body image domains. Discussion: Our results support the results of longitudinal studies demonstrating significant improvements in different aspects of body image, quality of life, and general psychopathology after bariatric surgery. Also, we found better AE and physical functioning in patients after BCS following bariatric surgery compared to patients with MWL after bariatric surgery who did not undergo BCS. Overall, there appears to be an effect of BCS on certain aspects of body image and quality of life but not on psychological aspects on the whole. PMID:25477839

  18. Body image and quality of life in patients with and without body contouring surgery following bariatric surgery: a comparison of pre- and post-surgery groups

    Directory of Open Access Journals (Sweden)

    Martina eDe Zwaan

    2014-11-01

    Full Text Available Background: Massive weight loss (MWL following bariatric surgery frequently results in an excess of overstretched skin causing physical discomfort and negatively affecting quality of life, self-esteem, body image and physical functioning.Methods: In this cross-sectional study 3 groups were compared: 1 patients prior to bariatric surgery (n=79, 2 patients after bariatric surgery who had not undergone BCS (n=252, and 3 patients after bariatric surgery who underwent subsequent body contouring surgery (BCS (n=62. All participants completed self-report questionnaires assessing body image (MBSRQ, quality of life (IWQOL-Lite, symptoms of depression (PHQ-9 and anxiety (GAD-7.Results: Overall, 62 patients (19.2% reported having undergone a total of 90 BCS procedures. The most common were abdominoplasties (88.7%, thigh lifts (24.2%, and breast lifts (16.1%. Post-bariatric surgery patients differed significantly in most variables from pre-bariatric surgery patients; however, there were fewer differences between patients with and without BCS. Patients after BCS reported better appearance evaluation, body area satisfaction, and physical functioning, even after controlling for excess weight loss and time since surgery. No differences were found for symptoms of depression and anxiety, and most other quality of life and body image domains. Discussion: Our results support the results of longitudinal studies demonstrating significant improvements in different aspects of body image, quality of life, and general psychopathology after bariatric surgery. Also, we found better appearance evaluation and physical functioning in patients after BCS following bariatric surgery compared to patients with MWL after bariatric surgery who did not undergo BCS. Overall, there appears to be an effect of BCS on certain aspects of body image and quality of life but not on psychological aspects on the whole.

  19. In vitro behaviors of rat mesenchymal stem cells on bacterial celluloses with different moduli

    Energy Technology Data Exchange (ETDEWEB)

    Taokaew, Siriporn [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330 (Thailand); Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906 (United States); Phisalaphong, Muenduen [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330 (Thailand); Zhang Newby, Bi-min, E-mail: bimin@uakron.edu [Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906 (United States)

    2014-05-01

    Compressive moduli of bacteria-synthesized cellulose (BC) were altered by two drying techniques: ambient-air drying and freeze drying. While no significant differences in dry weight were found, their cross-sectional structures and thickness varied greatly. Freeze dried BCs had loose cross-sectional structures and a thickness of ∼ 4.7 mm, whereas air dried BCs had more compacted cross-sectional structures and a thickness of ∼ 0.1 mm. The compressive moduli of the rehydrated freeze dried and rehydrated air dried BCs were measured to be 21.06 ± 0.22 kPa and 90.09 ± 21.07 kPa, respectively. When rat mesenchymal stem cells (rMSCs) were seeded on these BCs, they maintained a round morphology in the first 3 days of cultivation. More spread-out morphology and considerable proliferation on freeze dried BCs were observed in 7 days, but not on air-dried BCs. The cells were further grown for 3 weeks in the absence and presence of differentiation agents. Without using any differentiation agents, no detectable differentiation was noticed for rMSCs further cultivated on both types of BC. With differentiation inducing agents, chondrogenic differentiation, visualized by histological staining, was observed in some area of the rehydrated freeze dried BCs; while osteogenic differentiation was noticed on the stiffer rehydrated air dried BCs. - Graphical abstract: In the presence of induction agents, rat mesenchymal stem cells (rMSCs) preferentially differentiated into osteocytes on stiffer air dried BC films. - Highlights: • Bacterial cellulose (BC) sheets with different moduli generated by drying differently • Air-dried BC exhibited a modulus similar to that of bone. • Freeze-dried BC showed a modulus in the range of that of muscle. • Air-dried BC promoted the differentiation of rMSCs into osteocytes. • Freeze-dried BC promoted the differentiation of rMSCs into chondrocytes.

  20. String field theory-inspired algebraic structures in gauge theories

    International Nuclear Information System (INIS)

    Zeitlin, Anton M.

    2009-01-01

    We consider gauge theories in a string field theory-inspired formalism. The constructed algebraic operations lead, in particular, to homotopy algebras of the related Batalin-Vilkovisky theories. We discuss an invariant description of the gauge fixing procedure and special algebraic features of gauge theories coupled to matter fields.

  1. GROUNDED THEORY METHODOLOGY and GROUNDED THEORY RESEARCH in TURKEY

    OpenAIRE

    ARIK, Ferhat; ARIK, Işıl Avşar

    2016-01-01

    This research discusses the historical development of the Grounded Theory Methodology, which is one of the qualitative research method, its transformation over time and how it is used as a methodology in Turkey. The Grounded Theory which was founded by Strauss and Glaser, is a qualitative methodology based on inductive logic to discover theories in contrast with the deductive understanding which is based on testing an existing theory in sociology. It is possible to examine the Grounded Theory...

  2. Toroidal Superheavy Nuclei in Skyrme-Hartree-Fock Approach

    International Nuclear Information System (INIS)

    Staszczak, A.; Wong, Cheuk-Yin

    2009-01-01

    Within the self-consistent constraint Skyrme-Hartree-Fock+BCS model (SHF+BCS), we found equilibrium toroidal nuclear density distributions in the region of superheavy elements. For nuclei with a sufficient oblate deformation (Q 20 < -200 b), it becomes energetically favorable to change the genus of nuclear surface from 0 to 1, i.e., to switch the shape from a biconcave disc to a torus. The energy of the toroidal (genus=1) SHF+BCS solution relative to the compact (genus=0) ground state energy is strongly dependent both on the atomic number Z and the mass number A. We discuss the region of Z and A where the toroidal SHF+BCS total energy begins to be a global minimum

  3. On novel string theories from 4d gauge theories

    Directory of Open Access Journals (Sweden)

    Kiritsis Elias

    2014-04-01

    Full Text Available We investigate strings theories as defined from four dimensional gauge theories. It is argued that novel (superstring theories exist up to 26 dimensions. Some of them may support weakly curved geometries. A proposal is outlined to link their local conformal invariance to the dynamics of the bulk string theory.

  4. Capacidad de carga turÍstica como base para el manejo sustentable de actividades ecoturísticas en Unidades de Manejo Ambiental (UMA de Baja California Sur (BCS

    Directory of Open Access Journals (Sweden)

    Reyna Ibañez Pérez

    2016-01-01

    Full Text Available Existen zonas ejidales con UMA ́s, que desean incursionar en el turismo alternativo; tal es el caso del Nuevo Centro Poblacional Ejidal (NCPE, Ley Federal de Aguas Número 3, que se extiende a tres municipios de Baja California Sur (BCS, posee una UMA y se destaca por buscar opciones para reactivar su economía. En este trabajo se presentan los resultados de un estudio de Capacidad de Carga Turística (CCT, realizada en dos senderos de ese ejido, mediante la aplicación de la metodología de Cifuentes, que busca establecer el número máximo de visitas que puede recibir un área con base en sus condiciones físicas, biológicas y de manejo; cuya estimación, requirió de la revisión de censos de flora y fauna, de información geológica, climatológica, geográfica, ambiental, social, económica, turística, así como trabajo de campo. Los resultados indican que, en el NCPE, Ley Federal de Aguas Número 3, existen dos senderos con potencialidad turística para los cuales, se ha estimado una Capacidad de Carga Efectiva (CCE de 18 visitantes/día para el sendero del arroyo El Camarón y de 10 visitantes/día sendero del arroyo El Saucito. Las cifras anteriores, son un referente para el establecimiento de medidas de control de las visitas en ambos senderos

  5. Atomic theories

    CERN Document Server

    Loring, FH

    2014-01-01

    Summarising the most novel facts and theories which were coming into prominence at the time, particularly those which had not yet been incorporated into standard textbooks, this important work was first published in 1921. The subjects treated cover a wide range of research that was being conducted into the atom, and include Quantum Theory, the Bohr Theory, the Sommerfield extension of Bohr's work, the Octet Theory and Isotopes, as well as Ionisation Potentials and Solar Phenomena. Because much of the material of Atomic Theories lies on the boundary between experimentally verified fact and spec

  6. Phenomenological realism, superconductivity and quantum mechanics

    International Nuclear Information System (INIS)

    Shomar, T.L.E.

    1998-01-01

    The central aim of this thesis is to present a new kind of realism that is driven not from the traditional realism/anti-realism debate but from the practice of physicists. The usual debate focuses on discussions about the truth of theories and their fit with nature, while the real practices of the scientists are forgotten. The position I shall defend is called 'phenomenological realism': theories are merely tools to construct other theories and models, including phenomenological models; phenomenological models are the vehicles of representation. The realist doctrine was recently undermined by the argument from the pessimistic meta-induction, also known as the argument from scientific revolutions. I argue that phenomenological realism is a new kind of scientific realism which can overcome the problem generated by the argument from scientific revolutions, and which depend on the scientific practice. The realist tried to overcome this problem by suggesting various types of theory dichotomy. I claim that different types of dichotomy presented by realists did not overcome the problem, these dichotomies cut through theory vertically. I argue for a different kind of dichotomy between high level theoretical abstractions and low-level theoretical representations. I claim that theoretical work in physics have two distinct types depending on the way they are built these are: theoretical models which built depending on a top-down approach and phenomenological models which are built depending on a bottom-up approach, this dichotomy cuts the division along a horizontal line between low and high level theory. I present two case studies. One from superconductivity where I contrast the BCS theory of superconductivity with the phenomenological model of Landau and Ginzburg. I show how in that field of physics the historical developments favoured phenomenological models over high-level theoretical abstraction. I show how the BCS theory of superconductivity was constructed, and why it

  7. Theory and context / Theory in context

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre

    2014-01-01

    trans-disciplinary manner. Consideration needs to be given as well to connected scholarship focusing on imagination, innova-tion, and improvisation. Last but not least, an expanded the-ory of context cannot ignore the institutional context of doing research on creativity. Creativity scholars are facing......It is debatable whether the psychology of creativity is a field in crisis or not. There are clear signs of increased fragmenta-tion and a scarcity of integrative efforts, but is this necessari-ly bad? Do we need more comprehensive theories of creativ-ity and a return to old epistemological...... questions? This de-pends on how one understands theory. Against a view of theoretical work as aiming towards generality, universality, uniformity, completeness, and singularity, I advocate for a dynamic perspective in which theory is plural, multifaceted, and contextual. Far from ‘waiting for the Messiah...

  8. Bacterial cellulose synthesis mechanism of facultative anaerobe Enterobacter sp. FY-07.

    Science.gov (United States)

    Ji, Kaihua; Wang, Wei; Zeng, Bing; Chen, Sibin; Zhao, Qianqian; Chen, Yueqing; Li, Guoqiang; Ma, Ting

    2016-02-25

    Enterobacter sp. FY-07 can produce bacterial cellulose (BC) under aerobic and anaerobic conditions. Three potential BC synthesis gene clusters (bcsI, bcsII and bcsIII) of Enterobacter sp. FY-07 have been predicted using genome sequencing and comparative genome analysis, in which bcsIII was confirmed as the main contributor to BC synthesis by gene knockout and functional reconstitution methods. Protein homology, gene arrangement and gene constitution analysis indicated that bcsIII had high identity to the bcsI operon of Enterobacter sp. 638; however, its arrangement and composition were same as those of BC synthesizing operon of G. xylinum ATCC53582 except for the flanking sequences. According to the BC biosynthesizing process, oxygen is not directly involved in the reactions of BC synthesis, however, energy is required to activate intermediate metabolites and synthesize the activator, c-di-GMP. Comparative transcriptome and metabolite quantitative analysis demonstrated that under anaerobic conditions genes involved in the TCA cycle were downregulated, however, genes in the nitrate reduction and gluconeogenesis pathways were upregulated, especially, genes in three pyruvate metabolism pathways. These results suggested that Enterobacter sp. FY-07 could produce energy efficiently under anaerobic conditions to meet the requirement of BC biosynthesis.

  9. Evolution of accesses to information on breast cancer and screening on the Brazilian National Cancer Institute website: an exploratory study

    Directory of Open Access Journals (Sweden)

    Paulo Roberto Vasconcellos-Silva

    Full Text Available Abstract Delays in diagnosis due to low Breast Cancer awareness are widespread in Brazil maybe owing to ineffective strategies to raise attention on early diagnosis. As a proxy of collective interest in BC screanning (BCS we studied the monthly accesses to BC and BCS webpages in INCA's website along 48 months. A log analyzer built a time serie (2006-2009 of BC and BCS monthly means, which oscilations were studied by analysis of variance (ANOVA. We found significant increasing accesses to BC and transient “attention peaks”. Enlargement in BC/BCS differences along all period were caused by increasing accesses to BC and decreasing/minor/stable oscillations to SBC pages. These results are consistent with previous reports on increasing interest to BC contrasting with indifference on BCS. In the context of an exploratory study, we discussed some aspects: weakness of a “prevention culture”; lack of confidence in health system and screening programs; “celebrity effect” in the context of media framing; collective perception of risks heightened by perception of social vulnerability. Findings suggest that culture-tailored communication strategies would be necessary to inform Brazilian people about BCS. Future research is needed to study social perceptions and constructions on BC topics.

  10. Longitudinal trends with improvement in quality of life after TVT, TVT O and Burch colposuspension procedures.

    Science.gov (United States)

    Drahoradova, Petra; Martan, Alois; Svabik, Kamil; Zvara, Karel; Otava, Martin; Masata, Jaromir

    2011-02-01

    Comparison of the quality of life (QoL) trends after TVT, TVT O and Burch colposuspension (BCS) procedures and comparison of long-term subjective and objective outcomes. The study included 215 women who underwent a TVT, TVT O or BCS procedure. We monitored QoL after each procedure and the effect of complications on the QoL as assessed by the IQOL questionnaire over a 3-year period. The study was completed by 74.5% of women after TVT, 74.5% after TVT O, and 65.2% after BCS procedure. In the long-term, the QoL improved from 46.9 to 88.7 and remained stable after BCS; after TVT and TVT O, it declined, but only after TVT O was the decline statistically significant compared to BCS. The IQOL for women with post-operative complications has a clear descending tendency. The effect of the complications is highly significant (pTVT O, but not with TVT or BCS. Anti-incontinence operations significantly improve quality of life for women with MI, but compared to the SI group, the quality of life is worse when measured at a longer time interval after the operation. Anti-incontinence operations significantly improve quality of life, and the difference in preoperative status in the long-term follow-up is demonstrable.

  11. The rotor theories by Professor Joukowsky: Vortex theories

    DEFF Research Database (Denmark)

    Okulov, Valery L.; Sørensen, Jens Nørkær; Wood, David H.

    2015-01-01

    This is the second of two articles with the main, and largely self-explanatory, title "Rotor theories by Professor Joukowsky". This article considers rotors with finite number of blades and is subtitled "Vortex theories". The first article with subtitle "Momentum theories", assessed the starring...

  12. Consumer culture theory (re)visits actor-network theory

    DEFF Research Database (Denmark)

    Bajde, Domen

    2013-01-01

    The vocabulary and tactics developed by actor-network theory (ANT) can shed light on several ontological and epistemological challenges faced by consumer culture theory. Rather than providing ready-made theories or methods, our translation of ANT puts forward a series of questions and propositions...

  13. 'Theory of Mind' I: a theory of knowledge?

    Science.gov (United States)

    Plastow, Michael

    2012-06-01

    'Theory of mind' is a cognitive notion introduced by Simon Baron-Cohen and colleagues to explain certain deficits in autistic disorders. It has, however, been extended beyond this, and applied more broadly. It proposes a means of knowing the mind of others, and suggests that this means fails in autism. The epistemological basis of 'theory of mind' will be examined critically, not just in terms of its endeavour as a theory of knowledge, but also in regard to the principles that underlie it. The proponents of 'theory of mind' eschew the rich field of psychological and phenomenological research, privileging only the biological sciences into which they endeavour to place their theorizations. In doing this, they fail to recognize the epistemological problems involved. This leads to the theory remaining hamstrung by the very Cartesian ontological problems that it seeks to avoid. For some, 'theory of mind' is but an artefact of the cognitive approach that it employs. It is argued that these difficulties are compounded by the failure of 'theory of mind' to take account of the place of language in the interpersonal encounters it attempts to describe.

  14. Building International Business Theory: A Grounded Theory Approach

    OpenAIRE

    Gligor, David; Esmark, Carol; Golgeci, Ismail

    2016-01-01

    The field of international business (IB) is in need of more theory development (Morck & Yeung, 2007). As such, the main focus of our manuscript was to provide guidance on how to build IB specific theory using grounded theory (GT). Moreover, we contribute to future theory development by identifying areas within IB where GT can be applied and the type of research issues that can be addressed using this methodology. Finally, we make a noteworthy contribution by discussing some of GT’s caveats an...

  15. Resource reflecting functor and its application to non-uniformity

    Science.gov (United States)

    Srinivasan, Priyaa Varshinee; Sanders, Barry C.; Cockett, Robin

    In this work, we formulate an abstract approach to translate one resource theory to another. We adopt the notion of resource theories as partitioned symmetric monoidal categories and extend this notion by considering resource-reflecting functors between resource theories. A functor F is a structure preserving map and F is said to be resource-reflecting if F (g) being a free transformation implies that the transformation g is also free. Thus, a resource-reflecting functor demonstrates that the existence of a free transformation between two resources in the domain resource theory can be inferred from the existence of a free transformation in the codomain theory. As an example, we construct one such functor from the resource theory of non-uniformity to a resource theory of majorization. Thus, our work lays a foundation for expressing similarities between resource theories and for applying results achieved in one resource theory to another. An abstract approach to the translation between theories enables common patterns to be identified between resource theories thereby reducing the effort of solving the same problem for different theories. BCS appreciates financial support from Alberta Innovates, NSERC, China's 1000 Talent Plan and the IQIM, which is an NSF Physics Frontiers Centre (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-2644).

  16. Local homotopy theory

    CERN Document Server

    Jardine, John F

    2015-01-01

    This monograph on the homotopy theory of topologized diagrams of spaces and spectra gives an expert account of a subject at the foundation of motivic homotopy theory and the theory of topological modular forms in stable homotopy theory. Beginning with an introduction to the homotopy theory of simplicial sets and topos theory, the book covers core topics such as the unstable homotopy theory of simplicial presheaves and sheaves, localized theories, cocycles, descent theory, non-abelian cohomology, stacks, and local stable homotopy theory. A detailed treatment of the formalism of the subject is interwoven with explanations of the motivation, development, and nuances of ideas and results. The coherence of the abstract theory is elucidated through the use of widely applicable tools, such as Barr's theorem on Boolean localization, model structures on the category of simplicial presheaves on a site, and cocycle categories. A wealth of concrete examples convey the vitality and importance of the subject in topology, n...

  17. Unitary field theories

    International Nuclear Information System (INIS)

    Bergmann, P.G.

    1980-01-01

    A problem of construction of the unitary field theory is discussed. The preconditions of the theory are briefly described. The main attention is paid to the geometrical interpretation of physical fields. The meaning of the conceptions of diversity and exfoliation is elucidated. Two unitary field theories are described: the Weyl conformic geometry and Calitzy five-dimensioned theory. It is proposed to consider supersymmetrical theories as a new approach to the problem of a unitary field theory. It is noted that the supergravitational theories are really unitary theories, since the fields figuring there do not assume invariant expansion

  18. Dynamical systems V bifurcation theory and catastrophe theory

    CERN Document Server

    1994-01-01

    Bifurcation theory and catastrophe theory are two of the best known areas within the field of dynamical systems. Both are studies of smooth systems, focusing on properties that seem to be manifestly non-smooth. Bifurcation theory is concerned with the sudden changes that occur in a system when one or more parameters are varied. Examples of such are familiar to students of differential equations, from phase portraits. Moreover, understanding the bifurcations of the differential equations that describe real physical systems provides important information about the behavior of the systems. Catastrophe theory became quite famous during the 1970's, mostly because of the sensation caused by the usually less than rigorous applications of its principal ideas to "hot topics", such as the characterization of personalities and the difference between a "genius" and a "maniac". Catastrophe theory is accurately described as singularity theory and its (genuine) applications. The authors of this book, the first printing of w...

  19. A succession of theories: purging redundancy from disturbance theory.

    Science.gov (United States)

    Pulsford, Stephanie A; Lindenmayer, David B; Driscoll, Don A

    2016-02-01

    The topics of succession and post-disturbance ecosystem recovery have a long and convoluted history. There is extensive redundancy within this body of theory, which has resulted in confusion, and the links among theories have not been adequately drawn. This review aims to distil the unique ideas from the array of theory related to ecosystem change in response to disturbance. This will help to reduce redundancy, and improve communication and understanding between researchers. We first outline the broad range of concepts that have developed over the past century to describe community change in response to disturbance. The body of work spans overlapping succession concepts presented by Clements in 1916, Egler in 1954, and Connell and Slatyer in 1977. Other theories describing community change include state and transition models, biological legacy theory, and the application of functional traits to predict responses to disturbance. Second, we identify areas of overlap of these theories, in addition to highlighting the conceptual and taxonomic limitations of each. In aligning each of these theories with one another, the limited scope and relative inflexibility of some theories becomes apparent, and redundancy becomes explicit. We identify a set of unique concepts to describe the range of mechanisms driving ecosystem responses to disturbance. We present a schematic model of our proposed synthesis which brings together the range of unique mechanisms that were identified in our review. The model describes five main mechanisms of transition away from a post-disturbance community: (i) pulse events with rapid state shifts; (ii) stochastic community drift; (iii) facilitation; (iv) competition; and (v) the influence of the initial composition of a post-disturbance community. In addition, stabilising processes such as biological legacies, inhibition or continuing disturbance may prevent a transition between community types. Integrating these six mechanisms with the functional

  20. Effective actions for F-theory compactifications and tensor theories

    International Nuclear Information System (INIS)

    Bonetti, Federico

    2014-01-01

    In this thesis we study the low-energy effective dynamics emerging from a class of F-theory compactifications in four and six dimensions. We also investigate six-dimensional supersymmetric quantum field theories with self-dual tensors, motivated by the problem of describing the long-wavelength regime of a stack of M5-branes in M-theory. These setups share interesting common features. They both constitute examples of intrinsically non-perturbative physics. On the one hand, in the context of F-theory the non-perturbative character is encoded in the geometric formulation of this class of string vacua, which allows the complexified string coupling to vary in space. On the other hand, the dynamics of a stack of multiple M5-branes flows in the infrared to a novel kind of superconformal field theories in six dimensions - commonly referred to as (2,0) theories - that are expected to possess no perturbative weakly coupled regime and have resisted a complete understanding so far. In particular, no Lagrangian description is known for these models. The strategy we employ to address these two problems is also analogous. A recurring Leitmotif of our work is a transdimensional treatment of the system under examination: in order to extract information about dynamics in d dimensions we consider a (d-1)-dimensional setup. As far as F-theory compactifications are concerned, this is a consequence of the duality between M-theory and F-theory, which constitutes our main tool in the derivation of the effective action of F-theory compactifications. We apply it to six-dimensional F-theory vacua, obtained by taking the internal space to be an elliptically fibered Calabi-Yau threefold, but we also employ it to explore a novel kind of F-theory constructions in four dimensions based on manifolds with Spin(7) holonomy. With reference to six-dimensional (2,0) theories, the transdimensional character of our approach relies in the idea of studying these theories in five dimensions. Indeed, we

  1. Color symmetrical superconductivity in a schematic nuclear quark model

    DEFF Research Database (Denmark)

    Bohr, Henrik; Providencia, C.; da Providencia, J.

    2010-01-01

    In this letter, a novel BCS-type formalism is constructed in the framework of a schematic QCD inspired quark model, having in mind the description of color symmetrical superconducting states. In the usual approach to color superconductivity, the pairing correlations affect only the quasi-particle...... states of two colors, the single-particle states of the third color remaining unaffected by the pairing correlations. In the theory of color symmetrical superconductivity here proposed, the pairing correlations affect symmetrically the quasi-particle states of the three colors and vanishing net color...

  2. Detecting nonlocal Cooper pair entanglement by optical Bell inequality violation

    Energy Technology Data Exchange (ETDEWEB)

    Nigg, Simon E.; Tiwari, Rakesh P.; Walter, Stefan; Schmidt, Thomas L. [Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel (Switzerland)

    2015-07-01

    Based on the Bardeen Cooper Schrieffer (BCS) theory of superconductivity, the coherent splitting of Cooper pairs from a superconductor to two spatially separated quantum dots has been predicted to generate nonlocal pairs of entangled electrons. In order to test this hypothesis, we propose a scheme to transfer the spin state of a split Cooper pair onto the polarization state of a pair of optical photons. We show that the produced photon pairs can be used to violate a Bell inequality, unambiguously demonstrating the entanglement of the split Cooper pairs.

  3. Pairing fluctuation effects on the single-particle spectra for the superconducting state

    International Nuclear Information System (INIS)

    Pieri, P.; Pisani, L.; Strinati, G.C.

    2004-01-01

    Single-particle spectra are calculated in the superconducting state for a fermionic system with an attractive interaction, as functions of temperature and coupling strength from weak to strong. The fermionic system is described by a single-particle self-energy that includes pairing-fluctuation effects in the superconducting state. The theory reduces to the ordinary BCS approximation in weak coupling and to the Bogoliubov approximation for the composite bosons in strong coupling. Several features of the single-particle spectral function are shown to compare favorably with experimental data for cuprate superconductors

  4. Models of coherent exciton condensation

    International Nuclear Information System (INIS)

    Littlewood, P B; Eastham, P R; Keeling, J M J; Marchetti, F M; Simons, B D; Szymanska, M H

    2004-01-01

    That excitons in solids might condense into a phase-coherent ground state was proposed about 40 years ago, and has been attracting experimental and theoretical attention ever since. Although experimental confirmation has been hard to come by, the concepts released by this phenomenon have been widely influential. This tutorial review discusses general aspects of the theory of exciton and polariton condensates, focusing on the reasons for coherence in the ground state wavefunction, the BCS to Bose crossover(s) for excitons and for polaritons, and the relationship of the coherent condensates to standard lasers

  5. Models of coherent exciton condensation

    Energy Technology Data Exchange (ETDEWEB)

    Littlewood, P B [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Eastham, P R [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Keeling, J M J [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Marchetti, F M [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Simons, B D [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Szymanska, M H [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom)

    2004-09-08

    That excitons in solids might condense into a phase-coherent ground state was proposed about 40 years ago, and has been attracting experimental and theoretical attention ever since. Although experimental confirmation has been hard to come by, the concepts released by this phenomenon have been widely influential. This tutorial review discusses general aspects of the theory of exciton and polariton condensates, focusing on the reasons for coherence in the ground state wavefunction, the BCS to Bose crossover(s) for excitons and for polaritons, and the relationship of the coherent condensates to standard lasers.

  6. Condensation energy of the Nambu-Jona-Lasinio vacuum and the MIT bag constant

    International Nuclear Information System (INIS)

    Li, S.; Bhalerao, R.S.; Bhaduri, R.K.

    1991-01-01

    In this paper the energy densities of the vacuum in the Wigner and the Goldstone modes of the Nambu- Jona-Lasinio Hamiltonian are calculated. The difference of these two quantities is analogous to the condensation energy of a BCS superconductor, and is used here to estimate the temperature dependence of the MIT bag constant. The formalism of da Providencia et al is generalized to finite temperatures, yielding the same gap equation as the finite- temperature field theory. The thermodynamics of the vacuum in the two phases is studied

  7. An unconventional colour superconductor

    International Nuclear Information System (INIS)

    Huang Mei

    2007-01-01

    Superfluidity, or superconductivity with mismatched Fermi momenta, appears in many systems such as charge-neutral dense quark matter, asymmetric nuclear matter, and in imbalanced cold atomic gases. The mismatch plays the role of breaking the Cooper pairing, and the pair-breaking state cannot be properly described in the framework of standard BCS theory. I give a brief review on recent theoretical developments in understanding unconventional colour superconductivity, including a gapless colour superconductor, chromomagnetic instabilities and the Higgs instability in the gapless phase. I also introduce a possible new framework for describing an unconventional colour superconductor

  8. Identical bands at normal deformation: Necessity of going beyond the mean-field approach

    International Nuclear Information System (INIS)

    Sun, Y.; Wu, C.; Feng, D.H.; Egido, J.L.; Guidry, M.

    1996-01-01

    The validity of BCS theory has been questioned because the appearance of normally deformed identical bands in odd and even nuclei seems to contradict the conventional understanding of the blocking effect. This problem is examined with the projected shell model (PSM), which projects good angular momentum states and includes many-body correlations in both deformation and pairing channels. Satisfactory reproduction of identical band data by the PSM suggests that it may be necessary to go beyond the mean field to obtain a quantitative account of identical bands. copyright 1996 The American Physical Society

  9. The disappearing momentum of the supercurrent in the superconductor-to-normal phase transformation

    Science.gov (United States)

    Hirsch, J. E.

    2016-06-01

    A superconductor in a magnetic field has surface currents that prevent the magnetic field from penetrating its interior. These currents carry kinetic energy and mechanical momentum. When the temperature is raised and the system becomes normal the currents disappear. Where do the kinetic energy and mechanical momentum of the currents go, and how? Here we propose that the answer to this question reveals a key necessary condition for materials to be superconductors, that is not part of conventional BCS-London theory: superconducting materials need to have hole carriers.

  10. Life Origination Hydrate Theory (LOH-Theory) and Mitosis and Replication Hydrate Theory (MRH-Theory): three-dimensional PC validation

    Science.gov (United States)

    Kadyshevich, E. A.; Dzyabchenko, A. V.; Ostrovskii, V. E.

    2014-04-01

    Size compatibility of the CH4-hydrate structure II and multi-component DNA fragments is confirmed by three-dimensional simulation; it is validation of the Life Origination Hydrate Theory (LOH-Theory).

  11. Gauge theories

    International Nuclear Information System (INIS)

    Lee, B.W.

    1976-01-01

    Some introductory remarks to Yang-Mills fields are given and the problem of the Coulomb gauge is considered. The perturbation expansion for quantized gauge theories is discussed and a survey of renormalization schemes is made. The role of Ward-Takahashi identities in gauge theories is discussed. The author then discusses the renormalization of pure gauge theories and theories with spontaneously broken symmetry. (B.R.H.)

  12. Ethnodrama: An Innovative Knowledge Translation Tool in the Management of Lymphedema

    OpenAIRE

    Ahmed, Shahid; Quinlan, Elizabeth; McMullen, Linda; Thomas, Roanne; Fichtner, Pam; Block, Janice

    2015-01-01

    Background: Lymphedema can cause significant physical impairment and quality-of-life issues. Yet there is a gap in knowledge about lymphedema among breast cancer survivors (BCS), and health care professionals (HCP). Ethnodrama is an innovative knowledge translation strategy that uses theatrical performances for dissemination of research results. We evaluated the impact of live ethnodrama on HCP' and BCS' awareness and attitudes in relation to impact of lymphedema on BCS' lives. Methods: Ethno...

  13. General Theory versus ENA Theory: Comparing Their Predictive Accuracy and Scope.

    Science.gov (United States)

    Ellis, Lee; Hoskin, Anthony; Hartley, Richard; Walsh, Anthony; Widmayer, Alan; Ratnasingam, Malini

    2015-12-01

    General theory attributes criminal behavior primarily to low self-control, whereas evolutionary neuroandrogenic (ENA) theory envisions criminality as being a crude form of status-striving promoted by high brain exposure to androgens. General theory predicts that self-control will be negatively correlated with risk-taking, while ENA theory implies that these two variables should actually be positively correlated. According to ENA theory, traits such as pain tolerance and muscularity will be positively associated with risk-taking and criminality while general theory makes no predictions concerning these relationships. Data from Malaysia and the United States are used to test 10 hypotheses derived from one or both of these theories. As predicted by both theories, risk-taking was positively correlated with criminality in both countries. However, contrary to general theory and consistent with ENA theory, the correlation between self-control and risk-taking was positive in both countries. General theory's prediction of an inverse correlation between low self-control and criminality was largely supported by the U.S. data but only weakly supported by the Malaysian data. ENA theory's predictions of positive correlations between pain tolerance, muscularity, and offending were largely confirmed. For the 10 hypotheses tested, ENA theory surpassed general theory in predictive scope and accuracy. © The Author(s) 2014.

  14. Quantum Yang-Mills theory of Riemann surfaces and conformal field theory

    International Nuclear Information System (INIS)

    Killingback, T.P.

    1989-01-01

    It is shown that Yang-Mills theory on a smooth surface, when suitably quantized, is a topological quantum field theory. This topological gauge theory is intimately related to two-dimensional conformal field theory. It is conjectured that all conformal field theories may be obtained from Yang-Mills theory on smooth surfaces. (orig.)

  15. Grounded theory.

    Science.gov (United States)

    Harris, Tina

    2015-04-29

    Grounded theory is a popular research approach in health care and the social sciences. This article provides a description of grounded theory methodology and its key components, using examples from published studies to demonstrate practical application. It aims to demystify grounded theory for novice nurse researchers, by explaining what it is, when to use it, why they would want to use it and how to use it. It should enable nurse researchers to decide if grounded theory is an appropriate approach for their research, and to determine the quality of any grounded theory research they read.

  16. The association of ruminal pH and some metabolic parameters with conception rate at first artificial insemination in Thai dairy cows.

    Science.gov (United States)

    Inchaisri, Chaidate; Chanpongsang, Somchai; Noordhuizen, Jos; Hogeveen, Henk

    2013-06-01

    The objective of this study was to determine the association of metabolic parameters and cow associated factors with the conception rate at first insemination (FCR) in Thai dairy cows. The investigation was performed with 529 lactations from 32 smallholder dairy farms. At 3-6 weeks after parturition, blood samples and ruminal fluid were collected. Body condition scores (BCS) of cows were scored 1 week before expected calving date and at blood sampling date. Ruminal pH was measured at 2-4 h after morning feeding in ruminal fluid collected by ruminocentesis. Serum beta-hydroxybutyrate and serum urea nitrogen were measured by kinetic enzyme method. Cows with first insemination (AI) between 41 and 114 days postpartum were identified after pregnancy diagnosis for FCR. Breed, parity, interval from calving to first AI, BCS before calving, BCS after calving, loss in BCS after calving, SBHB, SUN, ruminal pH, and postpartum problems were selected as independent variables for a model with FCR as a dependent variable. A multivariable logistic regression model was used with farm as a random effect. Overall FCR was 27.2 %. The FCR depended on interval from calving to first AI, BCS before calving, and ruminal pH. The FCR between 69 and 91 days postpartum was significantly highest (45 %). Before calving, a cow with high BCS (≥ 3.5) had significantly greater FCR than a cow with low BCS (≤ 3.25; P<0.01). An increased ruminal pH raised significantly FCR (OR=2.53; P=0.03).

  17. Comparison of Attachment theory and Cognitive-Motivational Structure theory.

    Science.gov (United States)

    Malerstein, A J

    2005-01-01

    Attachment theory and Cognitive-Motivational Structure (CMS) are similar in most respects. They differ primarily in their proposal of when, during development, one's sense of the self and of the outside world are formed. I propose that the theories supplement each other after about age seven years--when Attachment theory's predictions of social function become unreliable, CMS theory comes into play.

  18. Generalizability theory and item response theory

    NARCIS (Netherlands)

    Glas, Cornelis A.W.; Eggen, T.J.H.M.; Veldkamp, B.P.

    2012-01-01

    Item response theory is usually applied to items with a selected-response format, such as multiple choice items, whereas generalizability theory is usually applied to constructed-response tasks assessed by raters. However, in many situations, raters may use rating scales consisting of items with a

  19. Nonrelativistic superstring theories

    International Nuclear Information System (INIS)

    Kim, Bom Soo

    2007-01-01

    We construct a supersymmetric version of the critical nonrelativistic bosonic string theory [B. S. Kim, Phys. Rev. D 76, 106007 (2007).] with its manifest global symmetry. We introduce the anticommuting bc conformal field theory (CFT) which is the super partner of the βγ CFT. The conformal weights of the b and c fields are both 1/2. The action of the fermionic sector can be transformed into that of the relativistic superstring theory. We explicitly quantize the theory with manifest SO(8) symmetry and find that the spectrum is similar to that of type IIB superstring theory. There is one notable difference: the fermions are nonchiral. We further consider noncritical generalizations of the supersymmetric theory using the superspace formulation. There is an infinite range of possible string theories similar to the supercritical string theories. We comment on the connection between the critical nonrelativistic string theory and the lightlike linear dilaton theory

  20. Recursion Theory Week

    CERN Document Server

    Müller, Gert; Sacks, Gerald

    1990-01-01

    These proceedings contain research and survey papers from many subfields of recursion theory, with emphasis on degree theory, in particular the development of frameworks for current techniques in this field. Other topics covered include computational complexity theory, generalized recursion theory, proof theoretic questions in recursion theory, and recursive mathematics.

  1. Probability theory

    CERN Document Server

    Dorogovtsev, A Ya; Skorokhod, A V; Silvestrov, D S; Skorokhod, A V

    1997-01-01

    This book of problems is intended for students in pure and applied mathematics. There are problems in traditional areas of probability theory and problems in the theory of stochastic processes, which has wide applications in the theory of automatic control, queuing and reliability theories, and in many other modern science and engineering fields. Answers to most of the problems are given, and the book provides hints and solutions for more complicated problems.

  2. How to Map Theory: Reliable Methods Are Fruitless Without Rigorous Theory.

    Science.gov (United States)

    Gray, Kurt

    2017-09-01

    Good science requires both reliable methods and rigorous theory. Theory allows us to build a unified structure of knowledge, to connect the dots of individual studies and reveal the bigger picture. Some have criticized the proliferation of pet "Theories," but generic "theory" is essential to healthy science, because questions of theory are ultimately those of validity. Although reliable methods and rigorous theory are synergistic, Action Identification suggests psychological tension between them: The more we focus on methodological details, the less we notice the broader connections. Therefore, psychology needs to supplement training in methods (how to design studies and analyze data) with training in theory (how to connect studies and synthesize ideas). This article provides a technique for visually outlining theory: theory mapping. Theory mapping contains five elements, which are illustrated with moral judgment and with cars. Also included are 15 additional theory maps provided by experts in emotion, culture, priming, power, stress, ideology, morality, marketing, decision-making, and more (see all at theorymaps.org ). Theory mapping provides both precision and synthesis, which helps to resolve arguments, prevent redundancies, assess the theoretical contribution of papers, and evaluate the likelihood of surprising effects.

  3. Little string theory from double-scaling limits of field theories

    International Nuclear Information System (INIS)

    Ling, Henry; Shieh, H.-H.; Anders, Greg van

    2007-01-01

    We show that little string theory on S 5 can be obtained as double-scaling limits of the maximally supersymmetric Yang-Mills theories on R x S 2 and R x S 3 /Z k . By matching the gauge theory parameters with those in the dual supergravity solutions found by Lin and Maldacena, we determine the limits in the gauge theories that correspond to decoupling of NS5-brane degrees of freedom. We find that for the theory on R x S 2 , the 't Hooft coupling must be scaled like ln 3 N, and on R x S 3 /Z k , like ln 2 N. Accordingly, taking these limits in these field theories gives Lagrangian definitions of little string theory on S 5

  4. Perturbation theory and coupling constant analyticity in two-dimensional field theories

    International Nuclear Information System (INIS)

    Simon, B.

    1973-01-01

    Conjectural material and results over a year old are presented in the discussion of perturbation theory and coupling constant analyticity in two-dimensional field theories. General properties of perturbation series are discussed rather than questions of field theory. The question is interesting for two reasons: First, one would like to understand why perturbation theory is such a good guide (to show that perturbation theory determines the theory in some way). Secondly, one hopes to prove that some or all of the theories are nontrivial. (U.S.)

  5. Extracting the Condensate Density from Projection Experiments with Fermi Gases

    International Nuclear Information System (INIS)

    Perali, A.; Pieri, P.; Strinati, G.C.

    2005-01-01

    A debated issue in the physics of the BCS-BEC crossover with trapped Fermi atoms is to identify characteristic properties of the superfluid phase. Recently, a condensate fraction was measured on the BCS side of the crossover by sweeping the system in a fast (nonadiabatic) way from the BCS to the Bose-Einstein condensation (BEC) sides, thus 'projecting' the initial many-body state onto a molecular condensate. We analyze here the theoretical implications of these projection experiments, by identifying the appropriate quantum-mechanical operator associated with the measured quantities and relating them to the many-body correlations occurring in the BCS-BEC crossover. Calculations are presented over wide temperature and coupling ranges, by including pairing fluctuations on top of the mean field

  6. Quenching characteristics of bathocuproinedisulfonic acid, disodium salt in aqueous solution and copper sulfate plating solution

    Science.gov (United States)

    Koga, Toshiaki; Hirakawa, Chieko; Takeshita, Michinori; Terasaki, Nao

    2018-04-01

    Bathocuproinedisulfonic acid, disodium salt (BCS) is generally used to detect Cu(I) through a color reaction. We newly found BCS fluorescence in the visible blue region in an aqueous solution. However, the fluorescence mechanism of BCS is not well known, so we should investigate its fundamental information. We confirmed that the characteristics of fluorescence are highly dependent on the molecular concentration and solvent properties. In particular, owing to the presence of the copper compound, the fluorescence intensity extremely decreases. By fluorescence quenching, we observed that a copper compound concentration of 10-6 mol/L or less could easily be measured in an aqueous solution. We also observed BCS fluorescence in copper sulfate plating solution and the possibility of detecting monovalent copper by fluorescence reabsorption.

  7. New Pathways between Group Theory and Model Theory

    CERN Document Server

    Fuchs, László; Goldsmith, Brendan; Strüngmann, Lutz

    2017-01-01

    This volume focuses on group theory and model theory with a particular emphasis on the interplay of the two areas. The survey papers provide an overview of the developments across group, module, and model theory while the research papers present the most recent study in those same areas. With introductory sections that make the topics easily accessible to students, the papers in this volume will appeal to beginning graduate students and experienced researchers alike. As a whole, this book offers a cross-section view of the areas in group, module, and model theory, covering topics such as DP-minimal groups, Abelian groups, countable 1-transitive trees, and module approximations. The papers in this book are the proceedings of the conference “New Pathways between Group Theory and Model Theory,” which took place February 1-4, 2016, in Mülheim an der Ruhr, Germany, in honor of the editors’ colleague Rüdiger Göbel. This publication is dedicated to Professor Göbel, who passed away in 2014. He was one of th...

  8. Quantum decision theory as quantum theory of measurement

    International Nuclear Information System (INIS)

    Yukalov, V.I.; Sornette, D.

    2008-01-01

    We present a general theory of quantum information processing devices, that can be applied to human decision makers, to atomic multimode registers, or to molecular high-spin registers. Our quantum decision theory is a generalization of the quantum theory of measurement, endowed with an action ring, a prospect lattice and a probability operator measure. The algebra of probability operators plays the role of the algebra of local observables. Because of the composite nature of prospects and of the entangling properties of the probability operators, quantum interference terms appear, which make actions noncommutative and the prospect probabilities nonadditive. The theory provides the basis for explaining a variety of paradoxes typical of the application of classical utility theory to real human decision making. The principal advantage of our approach is that it is formulated as a self-consistent mathematical theory, which allows us to explain not just one effect but actually all known paradoxes in human decision making. Being general, the approach can serve as a tool for characterizing quantum information processing by means of atomic, molecular, and condensed-matter systems

  9. Changing theories of change: strategic shifting in implicit theory endorsement.

    Science.gov (United States)

    Leith, Scott A; Ward, Cindy L P; Giacomin, Miranda; Landau, Enoch S; Ehrlinger, Joyce; Wilson, Anne E

    2014-10-01

    People differ in their implicit theories about the malleability of characteristics such as intelligence and personality. These relatively chronic theories can be experimentally altered, and can be affected by parent or teacher feedback. Little is known about whether people might selectively shift their implicit beliefs in response to salient situational goals. We predicted that, when motivated to reach a desired conclusion, people might subtly shift their implicit theories of change and stability to garner supporting evidence for their desired position. Any motivated context in which a particular lay theory would help people to reach a preferred directional conclusion could elicit shifts in theory endorsement. We examine a variety of motivated situational contexts across 7 studies, finding that people's theories of change shifted in line with goals to protect self and liked others and to cast aspersions on disliked others. Studies 1-3 demonstrate how people regulate their implicit theories to manage self-view by more strongly endorsing an incremental theory after threatening performance feedback or memories of failure. Studies 4-6 revealed that people regulate the implicit theories they hold about favored and reviled political candidates, endorsing an incremental theory to forgive preferred candidates for past gaffes but leaning toward an entity theory to ensure past failings "stick" to opponents. Finally, in Study 7, people who were most threatened by a previously convicted child sex offender (i.e., parents reading about the offender moving to their neighborhood) gravitated most to the entity view that others do not change. Although chronic implicit theories are undoubtedly meaningful, this research reveals a previously unexplored source of fluidity by highlighting the active role people play in managing their implicit theories in response to goals. 2014 APA, all rights reserved

  10. Genetic correlations among body condition score, yield and fertility in multiparous cows using random regression models

    OpenAIRE

    Bastin, Catherine; Gillon, Alain; Massart, Xavier; Bertozzi, Carlo; Vanderick, Sylvie; Gengler, Nicolas

    2010-01-01

    Genetic correlations between body condition score (BCS) in lactation 1 to 3 and four economically important traits (days open, 305-days milk, fat, and protein yields recorded in the first 3 lactations) were estimated on about 12,500 Walloon Holstein cows using 4-trait random regression models. Results indicated moderate favorable genetic correlations between BCS and days open (from -0.46 to -0.62) and suggested the use of BCS for indirect selection on fertility. However, unfavorable genetic c...

  11. Generalizability Theory and Classical Test Theory

    Science.gov (United States)

    Brennan, Robert L.

    2011-01-01

    Broadly conceived, reliability involves quantifying the consistencies and inconsistencies in observed scores. Generalizability theory, or G theory, is particularly well suited to addressing such matters in that it enables an investigator to quantify and distinguish the sources of inconsistencies in observed scores that arise, or could arise, over…

  12. Grounded theory: building a middle-range theory in nursing

    Directory of Open Access Journals (Sweden)

    Maria João Fernandes

    2015-03-01

    Full Text Available The development of nursing as a discipline results from a boom of investigations underway for nearly a century, and of the construction of theories that have arisen during the 1950’s, with greater relevance since the 1960’s. Giving continuation to the production of knowledge in nursing and seeking to contribute to the increase in the number of explanatory theories of the functional content of nurses, there is interest in answering the question: how can a middle-range theory in nursing be built that explains the nurse-elderly interaction in a successful aging process? As well, we address the goal of describing the process of building a middle-range theory in nursing. Middle-range theory refers to a qualitative paradigm study of inductive thinking, developed in the context of primary health care. The information was collected through participant observation and interviews. Method of analysis grounded theory by Corbin and Strauss(1 was followed, utilizing the triangulation of data and theoretical sampling. Grounded theory has become a method of analysis which facilitates the understanding and explanation of the phenomenon under study. By making clear the nature and process of the nurse-elderly interaction in the selected context and within the context of successful aging, a middle-range theory proposal emerged.

  13. String theory duals of Lifshitz–Chern–Simons gauge theories

    International Nuclear Information System (INIS)

    Balasubramanian, Koushik; McGreevy, John

    2012-01-01

    We propose candidate gravity duals for a class of non-Abelian z = 2 Lifshitz Chern–Simons (LCS) gauge theories studied by Mulligan, Kachru and Nayak. These are nonrelativistic gauge theories in 2+1 dimensions in which parity and time-reversal symmetries are explicitly broken by the presence of a Chern–Simons term. We show that these field theories can be realized as deformations of DLCQ N=4 super Yang–Mills theory. Using the holographic dictionary, we identify the bulk fields of type IIB supergravity that are dual to these deformations. The geometries describing the groundstates of the non-Abelian LCS gauge theories realized here exhibit a mass gap. (paper)

  14. The Landscape of Somatic Genetic Alterations in Breast Cancers From ATM Germline Mutation Carriers.

    Science.gov (United States)

    Weigelt, Britta; Bi, Rui; Kumar, Rahul; Blecua, Pedro; Mandelker, Diana L; Geyer, Felipe C; Pareja, Fresia; James, Paul A; Couch, Fergus J; Eccles, Diana M; Blows, Fiona; Pharoah, Paul; Li, Anqi; Selenica, Pier; Lim, Raymond S; Jayakumaran, Gowtham; Waddell, Nic; Shen, Ronglai; Norton, Larry; Wen, Hannah Y; Powell, Simon N; Riaz, Nadeem; Robson, Mark E; Reis-Filho, Jorge S; Chenevix-Trench, Georgia

    2018-02-28

    Pathogenic germline variants in ataxia-telangiectasia mutated (ATM), a gene that plays a role in DNA damage response and cell cycle checkpoints, confer an increased breast cancer (BC) risk. Here, we investigated the phenotypic characteristics and landscape of somatic genetic alterations in 24 BCs from ATM germline mutation carriers by whole-exome and targeted sequencing. ATM-associated BCs were consistently hormone receptor positive and largely displayed minimal immune infiltrate. Although 79.2% of these tumors exhibited loss of heterozygosity of the ATM wild-type allele, none displayed high activity of mutational signature 3 associated with defective homologous recombination DNA (HRD) repair. No TP53 mutations were found in the ATM-associated BCs. Analysis of an independent data set confirmed that germline ATM variants and TP53 somatic mutations are mutually exclusive. Our findings indicate that ATM-associated BCs often harbor bi-allelic inactivation of ATM, are phenotypically distinct from BRCA1/2-associated BCs, lack HRD-related mutational signatures, and that TP53 and ATM genetic alterations are likely epistatic.

  15. Addressing Factors Associated with Arab Women's Socioeconomic Status May Reduce Breast Cancer Mortality: Report from a Well Resourced Middle Eastern Country.

    Science.gov (United States)

    Donnelly, Tam Truong; Al Khater, Al-Hareth; Al Kuwari, Mohamed Ghaith; Al-Bader, Salha Bujassoum; Abdulmalik, Mariam; Al-Meer, Nabila; Singh, Rajvir; Fung, Tak

    2015-01-01

    Differences in socioeconomic status (SES) such as income levels may partly explain why breast cancer screening (BCS) disparities exist in countries where health care services are free or heavily subsidized. However, factors that contribute to such differences in SES among women living in well resourced Middle East countries are not fully understood. This quantitative study investigated factors that influence SES and BCS of Arab women. Understanding of such factors can be useful for the development of effective intervention strategies that aim to increase BCS uptake among Arab women. Using data from a cross-sectional survey among 1,063 Arabic-speaking women in Qatar, age 35+, additional data analysis was performed to determine the relationship between socioeconomic indicators such as income and other factors in relation to BCS activities. This study found that income is determined and influenced by education level, occupation, nationality, years of residence in the country, level of social activity, self-perceived health status, and living area. Financial stress, unemployment, and unfavorable social conditions may impede women's participation in BCS activities in well resourced Middle East countries.

  16. A sensitivity study on modeling black carbon in snow and its radiative forcing over the Arctic and Northern China

    International Nuclear Information System (INIS)

    Qian, Yun; Wang, Hailong; Rasch, Philip J; Zhang, Rudong; Flanner, Mark G

    2014-01-01

    Black carbon in snow (BCS) simulated in the Community Atmosphere Model (CAM5) is evaluated against measurements over Northern China and the Arctic, and its sensitivity to atmospheric deposition and two parameters that affect post-depositional enrichment is explored. Improvements in atmospheric BC transport and deposition significantly reduce the biases (by a factor of two) in the estimation of BCS concentration over both Northern China and the Arctic. Further sensitivity simulations using the improved CAM5 indicate that the melt-water scavenging efficiency (MSE) parameter plays an important role in regulating BC concentrations in the Arctic through the post-depositional enrichment, which not only drastically changes the amplitude but also shifts the seasonal cycle of the BCS concentration and its radiative forcing in the Arctic. The impact of the snow aging scaling factor (SAF) on BCS shows more complex latitudinal and seasonal dependence, and overall impact of SAF is much smaller than that of MSE. The improvements of BC transport and deposition in CAM5 have a stronger influence on BCS than perturbations of the two snow model parameters in Northern China. (letters)

  17. Introduction to conformal field theory. With applications to string theory

    International Nuclear Information System (INIS)

    Blumenhagen, Ralph; Plauschinn, Erik

    2009-01-01

    Based on class-tested notes, this text offers an introduction to Conformal Field Theory with a special emphasis on computational techniques of relevance for String Theory. It introduces Conformal Field Theory at a basic level, Kac-Moody algebras, one-loop partition functions, Superconformal Field Theories, Gepner Models and Boundary Conformal Field Theory. Eventually, the concept of orientifold constructions is explained in detail for the example of the bosonic string. In providing many detailed CFT calculations, this book is ideal for students and scientists intending to become acquainted with CFT techniques relevant for string theory but also for students and non-specialists from related fields. (orig.)

  18. G-theory: The generator of M-theory and supersymmetry

    Science.gov (United States)

    Sepehri, Alireza; Pincak, Richard

    2018-04-01

    In string theory with ten dimensions, all Dp-branes are constructed from D0-branes whose action has two-dimensional brackets of Lie 2-algebra. Also, in M-theory, with 11 dimensions, all Mp-branes are built from M0-branes whose action contains three-dimensional brackets of Lie 3-algebra. In these theories, the reason for difference between bosons and fermions is unclear and especially in M-theory there is not any stable object like stable M3-branes on which our universe would be formed on it and for this reason it cannot help us to explain cosmological events. For this reason, we construct G-theory with M dimensions whose branes are formed from G0-branes with N-dimensional brackets. In this theory, we assume that at the beginning there is nothing. Then, two energies, which differ in their signs only, emerge and produce 2M degrees of freedom. Each two degrees of freedom create a new dimension and then M dimensions emerge. M-N of these degrees of freedom are removed by symmetrically compacting half of M-N dimensions to produce Lie-N-algebra. In fact, each dimension produces a degree of freedom. Consequently, by compacting M-N dimensions from M dimensions, N dimensions and N degrees of freedom is emerged. These N degrees of freedoms produce Lie-N-algebra. During this compactification, some dimensions take extra i and are different from other dimensions, which are known as time coordinates. By this compactification, two types of branes, Gp and anti-Gp-branes, are produced and rank of tensor fields which live on them changes from zero to dimension of brane. The number of time coordinates, which are produced by negative energy in anti-Gp-branes, is more sensible to number of times in Gp-branes. These branes are compactified anti-symmetrically and then fermionic superpartners of bosonic fields emerge and supersymmetry is born. Some of gauge fields play the role of graviton and gravitino and produce the supergravity. The question may arise that what is the physical reason

  19. Elucidating the biosynthetic and regulatory mechanisms of flavonoid-derived bioactive components in Epimedium sagittatum

    Directory of Open Access Journals (Sweden)

    Wenjun eHuang

    2015-09-01

    Full Text Available Herba epimedii (Epimedium, a traditional Chinese medicine, has been widely used as a kidney tonic and antirheumatic medicine for thousands of years. In Epimedium, flavonoids have been demonstrated to be the main bioactive components (BCs. However, the molecular biosynthetic and regulatory mechanisms of flavonoid-derived BCs remain obscure. In this study, we isolated twelve structural genes and two putative transcription factors (TFs in the flavonoid pathway. Phytochemical analysis showed that the total content of four representative BCs (epimedin A, B, C and icariin decreased slightly or dramatically in two lines of E. sagittatum during leaf development. Transcriptional analysis revealed that two R2R3-MYB TFs (EsMYBA1 and EsMYBF1, together with a bHLH TF (EsGL3 and WD40 protein (EsTTG1, were supposed to coordinately regulate the anthocyanin and flavonol-derived BCs biosynthesis in leaves. Overexpression of EsFLS (flavonol synthase in tobacco resulted in increased flavonols content and decreased anthocyanins content in flowers. Moreover, EsMYB12 negatively correlated with the accumulation of the four BCs, and might act as a transcriptional repressor in the flavonoid pathway. Therefore, the anthocyanin pathway may coordinate with the flavonol-derived BCs pathway in Epimedium leaves. A better understanding of the flavonoid biosynthetic and regulatory mechanisms in E. sagittatum will facilitate functional characterization, metabolic engineering and molecular breeding studies of Epimedium species.

  20. Effects of long-term, near-term, and real-time energy balance, and blood progesterone concentrations, on the pregnancy rate of contemporary dairy cows.

    Science.gov (United States)

    Gomez, N A; Conley, A J; Robinson, P H

    2018-02-01

    This study aimed to contribute to understanding the interface between reproductive and nutritional energetic physiology in contemporary dairy cattle. Multiparous Holstein cows (n = 32) between 70 and 180 days in milk were used in a study starting 10 d prior to the artificial insemination (AI) date and were estrous synchronized using a hormonal regimen. Fourteen cows were determined pregnant on day 39 post-AI. Coccygeal blood samples of all cows were collected on d -10 and -3 prior to AI to determine estrous cyclicity, as well as at AI and at 6, 13 and 20 d post-AI. Milk progesterone was measured 20 d post-AI, and body condition was scored (BCS; 1-5 scale) on days -10, 0, 13 and 27 relative to AI. Blood non-esterified fatty acid concentrations, measured on the same days as BCS, and changes of BCS from d -10 to AI were not predictive of pregnancy outcome. The BCS of cows on the day of AI was greater (P = 0.02) for pregnant cows with an approximate minimum BCS for a high probability of conception being 2.50. Serum progesterone concentrations of pregnant cows were greater (P commercial high-producing multiparous dairy cattle may be partly due to breeding cows that have insufficient BCS to support pregnancy. Published by Elsevier B.V.

  1. A Sensitivity Study on Modeling Black Carbon in Snow and its Radiative Forcing over the Arctic and Northern China

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Yun; Wang, Hailong; Zhang, Rudong; Flanner, M. G.; Rasch, Philip J.

    2014-06-02

    Black carbon in snow (BCS) simulated in the Community Atmosphere Model (CAM5) is evaluated against measurements over Northern China and the Arctic, and its sensitivity to atmospheric deposition and two parameters that affect post-depositional enrichment is explored. The BCS concentration is overestimated (underestimated) by a factor of two in Northern China (Arctic) in the default model, but agreement with observations is good over both regions in the simulation with improvements in BC transport and deposition. Sensitivity studies indicate that uncertainty in the melt-water scavenging efficiency (MSE) parameter substantially affects BCS and its radiative forcing (by a factor of 2-7) in the Arctic through post-depositional enrichment. The MSE parameter has a relatively small effect on the magnitude of BCS seasonal cycle but can alter its phase in Northern China. The impact of the snow aging scaling factor (SAF) on BCS, partly through the post-depositional enrichment effect, shows more complex latitudinal and seasonal dependence. Similar to MSE, SAF affects more significantly the magnitude (phase) of BCS season cycle over the Arctic (Northern China). While uncertainty associated with the representation of BC transport and deposition processes in CAM5 is more important than that associated with the two snow model parameters in Northern China, the two uncertainties have comparable effect in the Arctic.

  2. Temperature dependence of differential conductance in Co-based Heusler alloy Co2TiSn and superconductor Pb junctions

    Science.gov (United States)

    Ooka, Ryutaro; Shigeta, Iduru; Umetsu, Rie Y.; Nomura, Akiko; Yubuta, Kunio; Yamauchi, Touru; Kanomata, Takeshi; Hiroi, Masahiko

    2018-05-01

    We investigated temperature dependence of differential conductance G (V) in planar junctions consisting of Co-based Heusler alloy Co2TiSn and superconductor Pb. Ferromagnetic Co2TiSn was predicted to be half-metal by first-principles band calculations. The spin polarization P of Co2TiSn was deduced to be 60.0% at 1.4 K by the Andreev reflection spectroscopy. The G (V) spectral shape was smeared gradually with increasing temperature and its structure was disappeared above the superconducting transition temperature Tc. Theoretical model analysis revealed that the superconducting energy gap Δ was 1.06 meV at 1.4 K and the Tc was 6.8 K , indicating that both values were suppressed from bulk values. However, the temperature dependent Δ (T) behavior was in good agreement with that of the Bardeen-Cooper-Schrieffer (BCS) theory. The experimental results exhibit that the superconductivity of Pb attached to half-metallic Co2TiSn was kept the conventional BCS mechanism characterized strong-coupling superconductors while its superconductivity was slightly suppressed by the superconducting proximity effect at the Co2TiSn/Pb interface.

  3. From F/M-theory to K-theory and back

    International Nuclear Information System (INIS)

    Garcia-Etxebarria, Inaki; Uranga, Angel M.

    2006-01-01

    We consider discrete K-theory tadpole cancellation conditions in type IIB orientifolds with magnetised 7-branes. Cancellation of K-theory charge constrains the choices of world-volume magnetic fluxes on the latter. We describe the F-/M-theory lift of these configurations, where 7-branes are encoded in the geometry of an elliptic fibration, and their magnetic quanta correspond to supergravity 4-form field strength fluxes. In a K3 compactification example, we show that standard quantization of 4-form fluxes as integer cohomology classes in K3 automatically implies the K-theory charge cancellation constraints on the 7-brane worldvolume magnetic fluxes in string theory (as well as new previously unnoticed discrete constraints, which we also interpret). Finally, we show that flux quantization in F-/M-theory implies that 7-brane world-volume flux quantization conditions are modified in the presence of 3-form fluxes

  4. From F/M-theory to K-theory and back

    CERN Document Server

    Garcia-Etxebarria, I; Garcia-Etxebarria, Inaki; Uranga, Angel M.

    2006-01-01

    We consider discrete K-theory tadpole cancellation conditions in type IIB orientifolds with magnetised 7-branes. Cancellation of K-theory charge constrains the choices of world-volume magnetic fluxes on the latter. We describe the F-/M-theory lift of these configurations, where 7-branes are encoded in the geometry of an elliptic fibration, and their magnetic quanta correspond to supergravity 4-form field strength fluxes. In a K3 compactification example, we show that standard quantization of 4-form fluxes as integer cohomology classes in K3 automatically implies the K-theory charge cancellation constraints on the 7-brane worldvolume magnetic fluxes in string theory (as well as new previously unnoticed discrete constraints, which we also interpret). Finally, we show that flux quantization in F-/M-theory implies that 7-brane world-volume flux quantization conditions are modified in the presence of 3-form fluxes.

  5. Galois Theory

    CERN Document Server

    Cox, David A

    2012-01-01

    Praise for the First Edition ". . .will certainly fascinate anyone interested in abstract algebra: a remarkable book!"—Monatshefte fur Mathematik Galois theory is one of the most established topics in mathematics, with historical roots that led to the development of many central concepts in modern algebra, including groups and fields. Covering classic applications of the theory, such as solvability by radicals, geometric constructions, and finite fields, Galois Theory, Second Edition delves into novel topics like Abel’s theory of Abelian equations, casus irreducibili, and the Galo

  6. Field theory

    CERN Multimedia

    1999-11-08

    In these lectures I will build up the concept of field theory using the language of Feynman diagrams. As a starting point, field theory in zero spacetime dimensions is used as a vehicle to develop all the necessary techniques: path integral, Feynman diagrams, Schwinger-Dyson equations, asymptotic series, effective action, renormalization etc. The theory is then extended to more dimensions, with emphasis on the combinatorial aspects of the diagrams rather than their particular mathematical structure. The concept of unitarity is used to, finally, arrive at the various Feynman rules in an actual, four-dimensional theory. The concept of gauge-invariance is developed, and the structure of a non-abelian gauge theory is discussed, again on the level of Feynman diagrams and Feynman rules.

  7. Concept theory

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2009-01-01

      Concept theory is an extremely broad, interdisciplinary and complex field of research related to many deep fields with very long historical traditions without much consensus. However, information science and knowledge organization cannot avoid relating to theories of concepts. Knowledge...... organizing systems (e.g. classification systems, thesauri and ontologies) should be understood as systems basically organizing concepts and their semantic relations. The same is the case with information retrieval systems. Different theories of concepts have different implications for how to construe......, evaluate and use such systems. Based on "a post-Kuhnian view" of paradigms this paper put forward arguments that the best understanding and classification of theories of concepts is to view and classify them in accordance with epistemological theories (empiricism, rationalism, historicism and pragmatism...

  8. Acceptability and characteristics of 124 human bioequivalence studies with active substances classified according to the Biopharmaceutic Classification System

    Science.gov (United States)

    Ramirez, Elena; Laosa, Olga; Guerra, Pedro; Duque, Blanca; Mosquera, Beatriz; Borobia, Alberto M; Lei, Suhua H; Carcas, Antonio J; Frias, Jesus

    2010-01-01

    AIM The aim of this study was to evaluate the acceptability of 124 bioequivalence (BE) studies with 80 active substances categorized according to the Biopharmaceutics Classification System (BCS) in order to establish if there were different probabilities of proving BE between the different BCS classes. METHODS We evaluated the differences between pharmaceutical products with active substances from different BCS classes in terms of acceptability, number of subjects in the study (n), the point estimates, and intra- and inter-subject coefficients of variation data from BE studies with generic products. RESULTS Out of 124 BE studies 89 (71.77%) were performed with pharmaceutical products containing active substances classified by the BCS. In all BCS classes there were non-bioequivalent pharmaceutical products: 4 out of 26 (15.38%) in class 1, 14 out of 28 (50%) in class 2, 3 out of 22 (13.63%) in class 3 and 1 out of 13 (7.69%) in class 4. When we removed those pharmaceutical products in which intra-subject variability was higher than predicted (2 in class 1 active substances, 9 in class 2 and 2 in class 3) there were still non-BE pharmaceutical products in classes 1, 2 and 3. CONCLUSIONS Comparisons between pharmaceutical products with active substances from the four BCS classes have not allowed us to define differential characteristics of each class in terms of n, inter and intra-subject variability for Cmax or AUC. Despite the usually employed test dissolution methodology proposed as quality control, pharmaceutical products with active substances from the four classes of BCS showed non-BE studies. PMID:21039763

  9. Development of an index based on ultrasonographic measurements for the objective appraisal of body condition in Andalusian horses

    Energy Technology Data Exchange (ETDEWEB)

    Martin-Gimenez, T.; Aguirre-Pascasio, C.N.; Blas, I. De

    2017-07-01

    Body condition scoring (BCS) is an indirect measure of the level of subcutaneous fat; however, by measuring the subcutaneous fat thicknesses (SFT), the precision of the degree of fatness assessment is improved. The aims were: 1) to develop an alternative body fat scoring index (BFSI) based on ultrasonographic measurements; 2) to assess the agreement between BCS and the new index applied to Andalusian horses; 3) to adjust the BCS cut-off values (if necessary) for overweight and obesity in this breed. One hundred and sixty-six Andalusian horses were included in this cross sectional study. On each horse, BCS, body fat percentage (BF%) and ultrasonography of SFT at localized deposits were evaluated. According to BFSI five possible body categories were established. Only one horse (0.6%) was classified as emaciated, 9.0% as thin, 74.7% as normal, 11.4% as overweight and 4.2% as obese. Despite higher BCS and SFT values were observed compared to other breeds, most of the horses evaluated presented a normal body condition under the new BFSI. BCS and BFSI were significantly associated (p<0.001), however, the concordance was low (weighted Cohen’s kappa coefficient, 0.262 ± 0.071; p=0.004). Using BFSI, obese horses had significantly greater BF% than the rest of categories (p<0.001). BCS showed a good diagnostic accuracy for detection overweight (AUC = 0.759 ± 0.055; p<0.001) and obese (AUC = 0.878 ± 0.050; p=0.001) horses; redefining the cut-off values for overweight and obesity condition as 7.5/9 and 8.5/9 respectively in Andalusian horses.

  10. Implementation of national body contouring surgery guidelines following massive weight loss: A national cross-sectional survey of commissioning in England.

    Science.gov (United States)

    Dunne, Jonathan A; Wormald, Justin C R; Ghedia, Reshma; Soldin, Mark

    2017-01-01

    National guidelines for commissioning of body contouring surgery (BCS) following massive weight loss (MWL) in England were published in 2014. Nearly three-quarters of patients who have MWL seek BCS; however, access is known to vary according to the region. The aim of national guidelines was to standardise access. The purpose of this study was to determine implementation of the national guidelines by clinical commissioning groups (CCGs) in England. A cross-sectional, web-based survey was sent to all CCG chairs in England. Of 211 potential respondents, 108 completed the survey or provided funding guidelines (response rate = 52%). Eight CCGs (7%) had implemented the guidelines. A total of 69 CCGs were aware of the new guidelines (64%), and 66 CCGs stated that they fund BCS after MWL (61%). A total of 81 CCGs (75%) identified local funding guidelines, while 15 CCGs (14%) cited individual funding requests (IFRs) as the means of accessing funding. To improve patient access to BCS; 58 of 65 respondents (89%) stated cost-effectiveness, whereas 56 of 75 respondents (75%) thought patient-reported outcome measures were key. Qualitative data to improve access included an integrated pathway from bariatric surgery to BCS, an improved evidence base and greater CCG finances. One CCG stated that it cannot afford to fund cosmetic procedures. The purpose of national guidelines was to simplify the pathway to BCS after MWL and create fair distribution of funds across the country to needy patients; however, their uptake has been poor. Access to funding for BCS across England varies according to the location. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  11. Geophysical Field Theory

    International Nuclear Information System (INIS)

    Eloranta, E.

    2003-11-01

    The geophysical field theory includes the basic principles of electromagnetism, continuum mechanics, and potential theory upon which the computational modelling of geophysical phenomena is based on. Vector analysis is the main mathematical tool in the field analyses. Electrostatics, stationary electric current, magnetostatics, and electrodynamics form a central part of electromagnetism in geophysical field theory. Potential theory concerns especially gravity, but also electrostatics and magnetostatics. Solid state mechanics and fluid mechanics are central parts in continuum mechanics. Also the theories of elastic waves and rock mechanics belong to geophysical solid state mechanics. The theories of geohydrology and mass transport form one central field theory in geophysical fluid mechanics. Also heat transfer is included in continuum mechanics. (orig.)

  12. Utilization of blood cultures in Danish hospitals

    DEFF Research Database (Denmark)

    Gubbels, S; Nielsen, J; Voldstedlund, M

    2015-01-01

    This national population-based study was conducted as part of the development of a national automated surveillance system for hospital-acquired bacteraemia and ascertains the utilization of blood cultures (BCs). A primary objective was to understand how local differences may affect interpretation......, Streptococcus pneumoniae, Enterococcus faecium, Enterococcus faecalis, Pseudomonas aeruginosa, Candida albicans, Enterobacter cloacae and Klebsiella oxytoca, accounted for 74.7% of agents for this purpose classified as pathogenic. An increase in BCs and positive BCs was observed over time, particularly among...

  13. Blood conservation strategies reduce the need for transfusions in ascending and aortic arch surgery.

    Science.gov (United States)

    Chu, M W A; Losenno, K L; Moore, K; Berta, D; Hewitt, J; Ralley, F

    2013-07-01

    Ascending and aortic arch surgery is associated with higher levels of blood loss and subsequent need for allogeneic blood transfusions. We hypothesized that aggressive, comprehensive blood conservation strategies may limit the need for transfusions and, subsequently, improve postoperative outcomes. Over a five-year period, 189 patients underwent proximal aortic surgery at our institution. Fifty-one patients underwent surgery using a comprehensive blood conservation strategy (BCS), including preoperative hemoglobin optimization, antifibrinolytic therapy, intraoperative acute normovolemic hemodilution, cell salvage and meticulous surgical technique. The remaining 138 patients underwent surgery using conventional techniques (CONV). Patients in the BCS group required fewer transfusions during their hospital stay compared to the conventional group (56.9% vs. 72.5%, p=0.041). When examining elective cases, this trend widens, with 40.0% of BCS patients requiring any transfusions compared to 72.9% patients in the conventional group (p=0.001). Red cell (47.1% vs. 62.3%, p=0.06), plasma (43.1% vs. 61.6%, p=0.02) and platelets (27.5% vs. 47.8%, p=0.01) were also less frequently required in the BCS group than the conventional group, respectively. When a transfusion was required, patients in the BCS group received significantly fewer units of red blood cells (2.8 ± 7.0 units) than the conventional group (5.81 ± 9.5 units; p=0.039). Mortality was similar in both groups (BCS 7.8%, conventional 10.9%, p=0.54); however, there was significantly less morbidity in the BCS group, using a composite of any of 10 major postoperative complications (23.5% vs. 39.1%; p=0.046). Median intensive care unit (ICU) and hospital lengths of stay were 2 and 7 days in the BCS group and 2 and 8 days in the CONV group (p=0.15), respectively. The aggressive use of a comprehensive blood conservation strategy in ascending and aortic arch surgery can significantly reduce the need for blood transfusions

  14. Breast conservation surgery versus total mastectomy among women with localized breast cancer in Soweto, South Africa

    Science.gov (United States)

    Dietz, Donald; Rosenbaum, Evan; Murugan, Nivashni; Chih, Ming Tsai; Ayeni, Oluwatosin; Dickens, Caroline; Crew, Katherine

    2017-01-01

    Purpose Breast conserving surgery (BCS) has become the preferred surgical option for the management of patients with nonmetastatic breast cancer in high-income countries. However, little is known about the distribution and determinants of BCS in low-and middle-income countries, especially those with high HIV prevalence. Methods We compared demographic and clinical characteristics of female patients who received BCS and those who received total mastectomy (TM) for nonmetastatic invasive carcinoma of the breast in Soweto, South Africa, 2009–2011. We also developed a multivariable logistic regression model of predictors of type of surgery. Results Of 445 patients, 354 (80%) underwent TM and 91 (20%) BCS. Of 373 patients screened for HIV, 59 (15.8%) tested positive. Eighty-two of 294 patients with stage I/II disease (28%), but just 9 of 151 (6%) with stage III disease had BCS (p<0.001). All women who received BCS (except for seven who received completion mastectomy within 6 weeks of BCS) and 235 (66.4%) women who received TM were referred for radiation therapy (RT). In our multivariable analysis, age group 50–59 years (OR = 2.28, 95% CI = 1.1–4.8) and ≥70 years (OR = 9.55, 95% CI = 2.9–31.2) vs. age group <40 years, stage at diagnosis (stage II (OR = 3.79, 95% CI = 1.6–8.2) and stage III (OR = 27.8, 95% CI = 9.0–78.8) vs. stage 1, HIV (HIV positive (OR = 3.19, 95% CI = 1.3–7.9) vs. HIV negative) and HER2-enriched subtype (OR = 3.50, 95% CI = 1.2–10.1) vs. triple negative were independently associated with TM. Conclusion TM was more common than BCS among patients with nonmetastatic breast cancer in Soweto, not only among patients with locally advanced disease at diagnosis, but also among women with stage I and II disease. PMID:28797046

  15. Generalized string theory mapping relations between gravity and gauge theory

    International Nuclear Information System (INIS)

    Bjerrum-Bohr, N.E.J.

    2003-01-01

    A previous study of the Kawai, Lewellen and Tye (KLT) relations between gravity and gauge theories, imposed by the relationship of closed and open strings, are here extended in the light of general relativity and Yang-Mills theory as effective field theories. We discuss the possibility of generalizing the traditional KLT mapping in this effective setting. A generalized mapping between the effective Lagrangians of gravity and Yang-Mills theory is presented, and the corresponding operator relations between gauge and gravity theories at the tree level are further explored. From this generalized mapping remarkable diagrammatic relations are found, linking diagrams in gravity and Yang-Mills theory, as well as diagrams in pure effective Yang-Mills theory. Also the possibility of a gravitational coupling to an antisymmetric field in the gravity scattering amplitude is considered, and shown to allow for mixed open-closed string solutions, i.e., closed heterotic strings

  16. Game theory and power theory : a critical comparison

    OpenAIRE

    Balzer, Wolfgang

    1992-01-01

    Social actions can be formulated in the frame of game theory or in a frame using, and foccussing on, the notion of power. The two frames are described and clarified. The comparison of theories from these two branches are evaluated from the point of theory of science.

  17. Game theory.

    Science.gov (United States)

    Dufwenberg, Martin

    2011-03-01

    Game theory is a toolkit for examining situations where decision makers influence each other. I discuss the nature of game-theoretic analysis, the history of game theory, why game theory is useful for understanding human psychology, and why game theory has played a key role in the recent explosion of interest in the field of behavioral economics. WIREs Cogni Sci 2011 2 167-173 DOI: 10.1002/wcs.119 For further resources related to this article, please visit the WIREs website. Copyright © 2010 John Wiley & Sons, Ltd.

  18. Systemic Thinking in Career Development Theory: Contributions of the Systems Theory Framework

    Science.gov (United States)

    McMahon, Mary; Patton, Wendy

    2018-01-01

    This article considers systemic thinking in relation to the Systems Theory Framework (STF) and to career theory. An overview of systems theory and its applications is followed by a discussion of career theory to provide a context for the subsequent description of STF. The contributions of STF to career theory and to theory integration are…

  19. Body condition score and plane of nutrition prepartum affect adipose tissue transcriptome regulators of metabolism and inflammation in grazing dairy cows during the transition period.

    Science.gov (United States)

    Vailati-Riboni, M; Kanwal, M; Bulgari, O; Meier, S; Priest, N V; Burke, C R; Kay, J K; McDougall, S; Mitchell, M D; Walker, C G; Crookenden, M; Heiser, A; Roche, J R; Loor, J J

    2016-01-01

    Recent studies demonstrating a higher incidence of metabolic disorders after calving have challenged the management practice of increasing dietary energy density during the last ~3 wk prepartum. Despite our knowledge at the whole-animal level, the tissue-level mechanisms that are altered in response to feeding management prepartum remain unclear. Our hypothesis was that prepartum body condition score (BCS), in combination with feeding management, plays a central role in the peripartum changes associated with energy balance and inflammatory state. Twenty-eight mid-lactation grazing dairy cows of mixed age and breed were randomly allocated to 1 of 4 treatment groups in a 2 × 2 factorial arrangement: 2 prepartum BCS categories (4.0 and 5.0, based on a 10-point scale; BCS4, BCS5) obtained via differential feeding management during late-lactation, and 2 levels of energy intake during the 3 wk preceding calving (75 and 125% of estimated requirements). Subcutaneous adipose tissue was harvested via biopsy at -1, 1, and 4 wk relative to parturition. Quantitative polymerase chain reaction was used to measure mRNA and microRNA (miRNA) expression of targets related to fatty acid metabolism (lipogenesis, lipolysis), adipokine synthesis, and inflammation. Both prepartum BCS and feeding management had a significant effect on mRNA and miRNA expression throughout the peripartum period. Overfed BCS5 cows had the greatest prepartum expression of fatty acid synthase (FASN) and an overall greater expression of leptin (LEP); BCS5 was also associated with greater overall adiponectin (ADIPOQ) and peroxisome proliferator-activated receptor gamma (PPARG), whereas overfeeding upregulated expression of proadipogenic miRNA. Higher postpartum expression of chemokine ligand 5 (CCL5) and the cytokines interleukin 6 (IL6) and tumor necrosis factor (TNF) was detected in overfed BCS5 cows. Feed-restricted BCS4 cows had the highest overall interleukin 1 (IL1B) expression. Prepartum feed restriction

  20. Application of fecal near-infrared spectroscopy and nutritional balance software to monitor diet quality and body condition in beef cows grazing Arizona rangeland.

    Science.gov (United States)

    Tolleson, D R; Schafer, D W

    2014-01-01

    Monitoring the nutritional status of range cows is difficult. Near-infrared spectroscopy (NIRS) of feces has been used to predict diet quality in cattle. When fecal NIRS is coupled with decision support software such as the Nutritional Balance Analyzer (NUTBAL PRO), nutritional status and animal performance can be monitored. Approximately 120 Hereford and 90 CGC composite (50% Red Angus, 25% Tarentaise, and 25% Charolais) cows grazing in a single herd were used in a study to determine the ability of fecal NIRS and NutbalPro to project BCS (1 = thin and 9 = fat) under commercial scale rangeland conditions in central Arizona. Cattle were rotated across the 31,000 ha allotment at 10 to 20 d intervals. Cattle BCS and fecal samples (approximately 500 g) composited from 5 to 10 cows were collected in the pasture approximately monthly at the midpoint of each grazing period. Samples were frozen and later analyzed by NIRS for prediction of diet crude protein (CP) and digestible organic matter (DOM). Along with fecal NIRS predicted diet quality, animal breed type, reproductive status, and environmental conditions were input to the software for each fecal sampling and BCS date. Three different evaluations were performed. First, fecal NIRS and NutbalPro derived BCS was projected forward from each sampling as if it were a "one-time only" measurement. Second, BCS was derived from the average predicted weight change between 2 sampling dates for a given period. Third, inputs to the model were adjusted to better represent local animals and conditions. Fecal NIRS predicted diet quality varied from a minimum of approximately 5% CP and 57% DOM in winter to a maximum of approximately 11% CP and 60% DOM in summer. Diet quality correlated with observed seasonal changes and precipitation events. In evaluation 1, differences in observed versus projected BCS were not different (P > 0.1) between breed types but these values ranged from 0.1 to 1.1 BCS in Herefords and 0.0 to 0.9 in CGC. In