Regularization of Diagrammatic Series with Zero Convergence Radius

The divergence of perturbative expansions for the vast majority of macroscopic systems, which follows from Dyson's collapse argument, prevents Feynman's diagrammatic technique from being directly used for controllable studies of strongly interacting systems. We show how the problem of divergence can be solved by replacing the original model with a convergent sequence of successive approximations which have a convergent perturbative series. As a prototypical model, we consider the zero-dimensional $\vert \psi \vert^4$ theory.Comment: 4 pages, 3 figure

Bio-material polylactic acid/poly(butylene adipate-co-terephthalate) blend developed for extrusion- based additive manufacturing

Bio-material polylactic acid and poly(butylene adipate-co-terephthalate) were blended to achieve increased ductility of the blend. Cloisite was added to improve the stiffness of the blend. The blends were made into filament suitable for extrusion-based additive manufacturing. Melt flow index of the filament and mechanical properties of the printed bars were tested. Preliminary results showed that the melt flow index increases significantly with cloisite and the modulus of polylactic acid/poly(butylene adipate-co-terephthalate) improved slightly. The notched impact strength of the blend increased with increasing content of cloisite, and it increased significantly after annealing, especially for blends without cloisite

Maximally inhomogeneous G\"{o}del-Farnsworth-Kerr generalizations

It is pointed out that physically meaningful aligned Petrov type D perfect fluid space-times with constant zero-order Riemann invariants are either the homogeneous solutions found by G\"{o}del (isotropic case) and Farnsworth and Kerr (anisotropic case), or new inhomogeneous generalizations of these with non-constant rotation. The construction of the line element and the local geometric properties for the latter are presented.Comment: 4 pages, conference proceeding of Spanish Relativity Meeting (ERE 2009, Bilbao

A randomised, double-blind, double-dummy comparative study of gatifloxacin with clarithromycin in the treatment of community-acquired pneumonia

ABSTRACTEligible patients were randomised in this multicentre, randomised, double-blind, double-dummy parallel-group study in a ratio of 1:1 to either gatifloxacin 400 mg once-daily for 5–14 days plus matching placebo, or clarithromycin 500 mg twice-daily for 5–14 days. The primary outcome measure was clinical response (clinical cure plus improvement) at the end of treatment. Secondary endpoints were clinical response at end of study, clinical cure at end of treatment and end of study, bacteriological response at end of treatment and end of study, and treatment duration. The overall clinical response was similar in the two treatment groups, with 92.2% of gatifloxacin-treated patients cured or improved at the end of treatment, compared with 93.1% of those receiving clarithromycin. Corresponding bacteriological response rates (eradication plus presumed eradication) were 96.7% and 87.5%, respectively. The study drugs were well-tolerated, with nausea (gatifloxacin) and bitter taste (clarithromycin) being the only treatment-related adverse events with a frequency of >5%. No patients experienced phototoxicity, hepatic or renal dysfunction, tendonitis or crystalluria. Oral gatifloxacin 400 mg once-daily appeared to be a safe and effective alternative to clarithromycin in the treatment of community-acquired pneumonia

Immunogenity of the pneumococcal polysaccharide vaccine in COPD patients. The effect of systemic steroids

AbstractRationale: To investigate if systemic steroids influence the antibody response to the 23-valent pneumococcal polysaccaride vaccine (23-PPV) in COPD patients.Patients and methods: COPD patients on: (a)⩾10mg of prednisolone/day (SS, n=30); (b) inhalative steroids (IS, n=30); (c) controls without COPD (CG, n=29) were vaccinated with 23-PPV. The concentration (μg/ml) of capsular specific anti-pneumococcal IgG antibodies (AB) for the serotypes (PNC) 4,6B,9V,14,18C,19F,23F were measured by Elisa technique before, 3 and 12 months (m) after vaccination. Non-responders were defined when AB-concentrations did neither doubled nor reach ⩾1μg/ml.Results: N=24 (CG), n=29 (IS), n=18 (SS) patients completed the study (mean age 64yrs.). Serious adverse events were not observed. Geometric mean (GM) AB-concentration of all serotypes increased significantly (CG, IS, SS) 3 and 12m after vaccination (P<0.05). The percentage of non-responders ranged between 16% (PNC 19F, IS) and 65% (PNC 4, SS) after 3m and 21% (PNC 19F, IS) and 82% (PNC 4, CG) after 12m. Neither post-vaccine AB-concentrations (3 and 12m) nor the rate of non-responders differed significantly between patients on systemic steroids and the other groups (IS, CG).Conclusions: Systemic steroids did not influence the AB-response. In all groups mean AB-concentration increased significantly after vaccination but an important percentage of subjects of all three groups were non-responders

Optimal Monte Carlo Updating

Based on Peskun's theorem it is shown that optimal transition matrices in Markov chain Monte Carlo should have zero diagonal elements except for the diagonal element corresponding to the largest weight. We will compare the statistical efficiency of this sampler to existing algorithms, such as heat-bath updating and the Metropolis algorithm. We provide numerical results for the Potts model as an application in classical physics. As an application in quantum physics we consider the spin 3/2 XY model and the Bose-Hubbard model which have been simulated by the directed loop algorithm in the stochastic series expansion framework.Comment: 6 pages, 5 figures, replaced with published versio

Rotating solenoidal perfect fluids of Petrov type D

We prove that aligned Petrov type D perfect fluids for which the vorticity vector is not orthogonal to the plane of repeated principal null directions and for which the magnetic part of the Weyl tensor with respect to the fluid velocity has vanishing divergence, are necessarily purely electric or locally rotationally symmetric. The LRS metrics are presented explicitly.Comment: 6 pages, no figure

Chromatin recruitment of activated AMPK drives fasting response genes co-controlled by GR and PPARα

Adaptation to fasting involves both Glucocorticoid Receptor (GRα) and Peroxisome Proliferator-Activated Receptor α (PPARα) activation. Given both receptors can physically interact we investigated the possibility of a genome-wide cross-talk between activated GR and PPARα, using ChIP- and RNA-seq in primary hepatocytes. Our data reveal extensive chromatin co-localization of both factors with cooperative induction of genes controlling lipid/glucose metabolism. Key GR/PPAR co-controlled genes switched from transcriptional antagonism to cooperativity when moving from short to prolonged hepatocyte fasting, a phenomenon coinciding with gene promoter recruitment of phosphorylated AMP-activated protein kinase (AMPK) and blocked by its pharmacological inhibition. In vitro interaction studies support trimeric complex formation between GR, PPARα and phospho-AMPK. Long-term fasting in mice showed enhanced phosphorylation of liver AMPK and GRα Ser211. Phospho-AMPK chromatin recruitment at liver target genes, observed upon prolonged fasting in mice, is dampened by refeeding. Taken together, our results identify phospho-AMPK as a molecular switch able to cooperate with nuclear receptors at the chromatin level and reveal a novel adaptation mechanism to prolonged fasting