20 research outputs found
O(N) and RP^{N-1} Models in Two Dimensions
I provide evidence that the 2D model for is equivalent
to the -invariant non-linear -model in the continuum limit. To
this end, I mainly study particular versions of the models, to be called
constraint models. I prove that the constraint and models are
equivalent for sufficiently weak coupling. Numerical results for their
step-scaling function of the running coupling are
presented. The data confirm that the constraint model is in the samei
universality class as the model with standard action. I show that the
differences in the finite size scaling curves of i and models
observed by Caracciolo et al. can be explained as a boundary effect. It is
concluded, in contrast to Caracciolo et al., that and models
share a unique universality class.Comment: 14 pages (latex) + 1 figure (Postscript) ,uuencode
Eigenvector localization for random band matrices with power law band width
It is shown that certain ensembles of random matrices with entries that
vanish outside a band around the diagonal satisfy a localization condition on
the resolvent which guarantees that eigenvectors have strong overlap with a
vanishing fraction of standard basis vectors, provided the band width
raised to a power remains smaller than the matrix size . For a
Gaussian band ensemble, with matrix elements given by i.i.d. centered Gaussians
within a band of width , the estimate holds.Comment: 30 pages; corrected typo
The scaling limit of the critical one-dimensional random Schrodinger operator
We consider two models of one-dimensional discrete random Schrodinger
operators (H_n \psi)_l ={\psi}_{l-1}+{\psi}_{l +1}+v_l {\psi}_l,
{\psi}_0={\psi}_{n+1}=0 in the cases v_k=\sigma {\omega}_k/\sqrt{n} and
v_k=\sigma {\omega}_k/ \sqrt{k}. Here {\omega}_k are independent random
variables with mean 0 and variance 1.
We show that the eigenvectors are delocalized and the transfer matrix
evolution has a scaling limit given by a stochastic differential equation. In
both cases, eigenvalues near a fixed bulk energy E have a point process limit.
We give bounds on the eigenvalue repulsion, large gap probability, identify the
limiting intensity and provide a central limit theorem.
In the second model, the limiting processes are the same as the point
processes obtained as the bulk scaling limits of the beta-ensembles of random
matrix theory. In the first model, the eigenvalue repulsion is much stronger.Comment: 36 pages, 2 figure
The extended empirical process test for non-Gaussianity in the CMB, with an application to non-Gaussian inflationary models
In (Hansen et al. 2002) we presented a new approach for measuring
non-Gaussianity of the Cosmic Microwave Background (CMB) anisotropy pattern,
based on the multivariate empirical distribution function of the spherical
harmonics a_lm of a CMB map. The present paper builds upon the same ideas and
proposes several improvements and extensions. More precisely, we exploit the
additional information on the random phases of the a_lm to provide further
tests based on the empirical distribution function. Also we take advantage of
the effect of rotations in improving the power of our procedures. The suggested
tests are implemented on physically motivated models of non-Gaussian fields;
Monte-Carlo simulations suggest that this approach may be very promising in the
analysis of non-Gaussianity generated by non-standard models of inflation. We
address also some experimentally meaningful situations, such as the presence of
instrumental noise and a galactic cut in the map.Comment: 15 pages, 6 figures, submitted to Phys. Rev.
Testing for non-Gaussianity of the cosmic microwave background in harmonic space: an empirical process approach
We present a new, model-independent approach for measuring non-Gaussianity of
the Cosmic Microwave Background (CMB) anisotropy pattern. Our approach is based
on the empirical distribution function of the normalized spherical harmonic
expansion coefficients a_lm of a nearly full-sky CMB map, like the ones
expected from forthcoming satellite experiments. Using a set of
Kolmogorov-Smirnov type tests, we check for Gaussianity and independency of the
a_lm. We test the method on two non-Gaussian toy-models of the CMB, one
generated in spherical harmonic space and one in pixel (real) space. We also
provide some rigorous results, possibly of independent interest, on the exact
distribution of the spherical harmonic coefficients normalized by an estimated
angular power spectrum.Comment: 29 pages, 7 figures, submitted to Phys. Rev.
Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.
BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362
Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTICâHF: baseline characteristics and comparison with contemporary clinical trials
Aims:
The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTICâHF) trial. Here we describe the baseline characteristics of participants in GALACTICâHF and how these compare with other contemporary trials.
Methods and Results:
Adults with established HFrEF, New York Heart Association functional class (NYHA)ââ„âII, EF â€35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokineticâguided dosing: 25, 37.5 or 50âmg bid). 8256 patients [male (79%), nonâwhite (22%), mean age 65âyears] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NTâproBNP 1971âpg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTICâHF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressureâ<â100âmmHg (n = 1127), estimated glomerular filtration rate <â30âmL/min/1.73 m2 (n = 528), and treated with sacubitrilâvalsartan at baseline (n = 1594).
Conclusions:
GALACTICâHF enrolled a wellâtreated, highârisk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation
Hemodialysis and biotransformation of erythrocyte epoxy fatty acids in peripheral tissue
Cardiovascular disease is the leading cause of mortality in patients with renal failure. Red blood cells (RBCs) are potential reservoirs for epoxy fatty acids (oxylipins) that regulate cardiovascular function. Hemoglobin exhibits pseudo-lipoxygenase activity in vitro. We previously assessed the impact of single hemodialysis (HD) treatment on RBC epoxy fatty acids status in circulating arterial blood and found that eicosanoids in oxygenated RBCs could be particularly vulnerable in chronic kidney disease and hemodialysis. The purpose of the present study was to evaluate the differences of RBC epoxy fatty acids profiles in arterial and venous blood in vivo (AV differences) from patients treated by HD treatment. We collected arterial and venous blood samples in upper limbs from 12 end-stage renal disease (ESRD) patients (age 72±12 years) before and after HD treatment. We measured oxylipins derived from cytochrome P450 (CYP) monooxygenase and lipoxygenase (LOX)/CYP Ï/(Ï-1)-hydroxylase pathways in RBCs by LC-MS/MS tandem mass spectrometry. Our data demonstrate arteriovenous differences in LOX pathway metabolites in RBCs after dialysis, including numerous hydroxyeicosatetraenoic acids (HETEs), hydroxydocosahexaenoic acids (HDHAs) and hydroxyeicosapentaenoic acids (HEPEs). We detected more pronounced changes in free metabolites in RBCs after HD, as compared with the total RBC compartment. Hemodialysis treatment did not affect the majority of CYP and CYP Ï/(Ï-1)-hydroxylase products in RBCs. Our data indicate that erythro-metabolites of the LOX pathway are influenced by renal-replacement therapies, which could have deleterious effects in the circulation
Genome-wide association study identifies a psoriasis susceptibility locus at TRAF3IP2.
Psoriasis is a multifactorial skin disease characterized by epidermal hyperproliferation and chronic inflammation, the most common form of which is psoriasis vulgaris (PsV). We present a genome-wide association analysis of 2,339,118 SNPs in 472 PsV cases and 1,146 controls from Germany, with follow-up of the 147 most significant SNPs in 2,746 PsV cases and 4,140 controls from three independent replication panels. We identified an association at TRAF3IP2 on 6q21 and genotyped two SNPs at this locus in two additional replication panels (the combined discovery and replication panels consisted of 6,487 cases and 8,037 controls; combined P = 2.36 × 10⻹Ⱐfor rs13210247 and combined P = 1.24 × 10⻹ⶠfor rs33980500). About 15% of psoriasis cases develop psoriatic arthritis (PsA). A stratified analysis of our datasets including only PsA cases (1,922 cases compared to 8,037 controls, P = 4.57 × 10⻹² for rs33980500) suggested that TRAF3IP2 represents a shared susceptibility for PsV and PsA. TRAF3IP2 encodes a protein involved in IL-17 signaling and which interacts with members of the Rel/NF-κB transcription factor family