Resonant and nonresonant D+ -> K- pi+ l+ nu(l) semileptonic decays

We analyse the semileptonic decay D+ -> K- pi+ l+ nu(l) using an effective Lagrangian developed previously to describe the decays D -> P l nu(l) and D -> V l nu(l). Light vector mesons are included in the model which combines the heavy quark effective Lagrangian and chiral perturbation theory approach. The nonresonant and resonant contributions are compared. With no new parameters the model correctly reproduces the measured ratio Gamma(nres)/Gamma(nres + res). We also present useful nonresonant decay distributions. Finally, a similar model, but with a modified current which satisfies the soft pion theorems at the expense of introducing another parameter, is analyzed and the results of the models are compared.Comment: 17 pages, 3 Postscript figures, standard Latex, extended revision, title, abstract and text (especially Sec. IV) changed, results unchange

Diagnosis and treatment of pseudoachalasia: how to catch the mimic

Published: 25 June 2020Pseudoachalasia, or secondary achalasia, is an uncommon esophageal dysmotility syndrome with symptoms and manometric findings indistinguishable from primary achalasia, but due to any mechanism other than idiopathic degeneration of the inhibitory neurons of the esophageal submucosal myenteric plexus. Whilst pseudoachalasia is rare, affecting some 1.4–5.4% of all achalasia patients, it is essential this diagnosis is always considered and excluded, as the treatment and outcomes for these patients will be very different from those with true achalasia. Pseudoachalasia can be difficult to differentiate from primary or “idiopathic achalasia”. Several particular clinical features have been described as more common in patients with pseudoachalasia than in achalasia, but because of the low prevalence of this condition, the positive predictive value remains low. The majority of patients with pseudoachalasia have an underlying malignancy, predominantly gastro-esophageal adenocarcinoma, which is usually advanced. Management revolves around treating the underlying cause where possible, as this may lead to reversal of the esophageal dysmotility. In patients presenting with symptoms and manometry findings consistent with achalasia, the diagnosis initially should be one of an achalasia-like syndrome. Idiopathic achalasia can then only be confirmed after other potential causes have been considered and excluded. We describe a case of pseudoachalasia encountered in our clinical practice, followed by a review of current practice regarding diagnosis and management of pseudoachalasia.Dylan R. Barnett, George L. Balalis, Jennifer C. Myers, Peter G. Devit

Unconscious associations between stressor type and ability to cope: An experimental approach using ancient and modern sources of stress

Objectives: Work has emerged that suggests it is salient and feasible to include a chronological approach to the taxonomy of stress. The ability to make an explicit distinction between ancient stressors (AS) and modern stressors (MS) has been reported in young and older adults; AS have been associated with greater ability to cope and MS with poorer health outcomes. Whether these explicit distinctions exist at an implicit, unconscious level, has yet to be determined. Design: A quantitative design employed a computer-based Implicit Association Test (IAT) to examine implicit associations between AS/MS and coping appraisal. Methods: One hundred adults (75 females) aged 18–58 years (M = 28.27 years, SD = 10.02) completed the AS/MS IAT, to compare reaction time (RT) and accuracy between consistent pairs (AS/ability to cope; MS/inability to cope) and inconsistent pair responses (AS/inability to cope; MS/ability to cope); followed by an explicit self-report questionnaire. Results: Repeated measures ANCOVAs, controlling for sex and age, revealed significant main effects of faster RT and higher accuracy in responses for consistent than inconsistent pairs. Adult participants made implicit associations indicating an unconscious AS and MS distinction. Using the D algorithm, a univariate ANCOVA and independent t-tests found that males, compared to females, showed a stronger implicit preference for consistent than inconsistent pairs. Conclusions: Findings suggest an implicit association between ancient and modern stressors and perceived coping ability. Utilizing a chronological taxonomy for understanding evolutionary origins that drive individual’s responses to stress has implications for developing effective coping strategies to improve health outcomes

Glueball spectrum based on a rigorous three-dimensional relativistic equation for two-gluon bound states II: calculation of the glueball spectrum

In the preceding paper, a rigorous three-dimensional relativistic equation for two-gluon bound states was derived from the QCD with massive gluons and represented in the angular momentum representation. In order to apply this equation to calculate the glueball spectrum, in this paper, the equation is recast in an equivalent three-dimensional relativistic equation satisfied by the two-gluon positive energy state amplitude. The interaction Hamiltonian in the equation is exactly derived and expressed as a perturbative series. The first term in the series describes the one-gluon exchange interaction which includes fully the retardation effect in it. This term plus the linear confining potential are chosen to be the interaction Hamiltonian and employed in the practical calculation. With the integrals containing three and four spherical Bessel functions in the QCD vertices being analytically calculated, the interaction Hamiltonian is given an explicit expression in the angular momentum representation. Numerically solving the relativistic equation with taking the contributions arising from the retardation effect and the longitudinal mode of gluon fields into account, a set of masses for the $0^{++},0^{-+},1^{++},1^{-+},2^{++}$ and $2^{-+\text{}}$ glueball states are obtained and are in fairly good agreement with the predictions given by the lattice simulatio

An open extensible tool environment for Event-B

Abstract. We consider modelling indispensable for the development of complex systems. Modelling must be carried out in a formal notation to reason and make meaningful conjectures about a model. But formal modelling of complex systems is a difficult task. Even when theorem provers improve further and get more powerful, modelling will remain difficult. The reason for this that modelling is an exploratory activity that requires ingenuity in order to arrive at a meaningful model. We are aware that automated theorem provers can discharge most of the onerous trivial proof obligations that appear when modelling systems. In this article we present a modelling tool that seamlessly integrates modelling and proving similar to what is offered today in modern integrated development environments for programming. The tool is extensible and configurable so that it can be adapted more easily to different application domains and development methods.

Global Standards in Action: Insights from Anti-Money Laundering Regulation

As organizations have come under the increasing influence of global rules of all sorts, organization scholars have started studying the dynamics of global regulation. The purpose of this article is to identify and evaluate the contribution to this interdisciplinary field by the ‘Stockholm Centre for Organisational Research’. The latter’s key proposition is that while global regulation often consists of voluntary best practice rules it can nevertheless become highly influential under certain conditions. We assess how innovative this approach is using as a benchmark the state of the art in another field of relevance to the study of global regulation, i.e. ‘International Relations’. Our discussion is primarily theoretical but we draw on the case of global anti-money laundering regulation to illustrate our arguments and for inspirations of how to further elaborate the approach

Glueball spectrum based on a rigorous three-dimensional relativistic equation for two-gluon bound states I: Derivation of the relativistic equation

A rigorous three-dimensional relativistic equation satisfied by two-gluon bound states is derived from the QCD with massive gluons. With the gluon fields and the quark fields being expanded in terms of the gluon multipole fields and the spherical Dirac spinors respectively, the equation is well established in the angular momentum representation and hence is much convenient for solving the problem of two-gluon glueball spectra. In particular, the interaction kernel in the equation is exactly derived and given a closed expression which includes all the interactions taking place in the two-gluon glueballs. The kernel contains only a few types of Green's functions and commutators. Therefore, it is not only easily calculated by the perturbation method, but also provides a suitable basis for nonperturbative investigations

Drell-Yan diffraction: breakdown of QCD factorisation

We consider the diffractive Drell-Yan process in proton-(anti)proton collisions at high energies in the color dipole approach. The calculations are performed at forward rapidities of the leptonic pair. Effect of eikonalization of the universal "bare"dipole-target elastic amplitude in the saturation regime takes into account the principal part of the gap survival probability. We present predictions for the total and differential cross sections of the single diffractive lepton pair production at RHIC and LHC energies. We analyze implications of the QCD factorisation breakdown in the diffractive Drell-Yan process, which is caused by a specific interplay of the soft and hard interactions, and resulting in rather unusual properties of the corresponding observables.Comment: 19 pages, 7 figure

A lattice model for the kinetics of rupture of fluid bilayer membranes

We have constructed a model for the kinetics of rupture of membranes under tension, applying physical principles relevant to lipid bilayers held together by hydrophobic interactions. The membrane is characterized by the bulk compressibility (for expansion), the thickness of the hydrophobic part of the bilayer, the hydrophobicity and a parameter characterizing the tail rigidity of the lipids. The model is a lattice model which incorporates strain relaxation, and considers the nucleation of pores at constant area, constant temperature, and constant particle number. The particle number is conserved by allowing multiple occupancy of the sites. An equilibrium ``phase diagram'' is constructed as a function of temperature and strain with the total pore surface and distribution as the order parameters. A first order rupture line is found with increasing tension, and a continuous increase in proto-pore concentration with rising temperature till instability. The model explains current results on saturated and unsaturated PC lipid bilayers and thicker artificial bilayers made of diblock copolymers. Pore size distributions are presented for various values of area expansion and temperature, and the fractal dimension of the pore edge is evaluated.Comment: 15 pages, 8 figure