Gauge Theory in d=2+1 at High Temperature: Z_N interface

We calculate on the lattice the interface tension in the SU(2) pure gauge theory in d=2+1 at high temperature. The result is compared to the perturbative prediction. The agreement confirms applicability of the perturbation theory in this case.Comment: Lattice'94 contribution, 3pp, uuencoded compressed postscrip

Local Decoders for the 2D and 4D Toric Code

We analyze the performance of decoders for the 2D and 4D toric code which are local by construction. The 2D decoder is a cellular automaton decoder formulated by Harrington which explicitly has a finite speed of communication and computation. For a model of independent $X$ and $Z$ errors and faulty syndrome measurements with identical probability we report a threshold of $0.133\%$ for this Harrington decoder. We implement a decoder for the 4D toric code which is based on a decoder by Hastings arXiv:1312.2546 . Incorporating a method for handling faulty syndromes we estimate a threshold of $1.59\%$ for the same noise model as in the 2D case. We compare the performance of this decoder with a decoder based on a 4D version of Toom's cellular automaton rule as well as the decoding method suggested by Dennis et al. arXiv:quant-ph/0110143 .Comment: 22 pages, 21 figures; fixed typos, updated Figures 6,7,8,

Hypertrophic Cardiomyopathy: Pathophysiology, Genetics and Invasive Treatment

Hypertrophic cardiomyopathy (HCM) is the most common inheritable cardiac disorder with a phenotypic prevalence of 1:500. It is defined by the presence of left ventricular hypertrophy (LVH) in the absence of loading conditions (hypertension, valve disease) sufficient to cause the observed abnormality. Hundreds of mutations scattered among at least 25 putative HCM susceptibility genes encoding various sarcomere, Z-disk, calciumhandling, and mitochondrial proteins are known to cause HCM and are found in up to 60% of cases. Besides the genetic heterogeneity, HCM is also characterized by phenotypic heterogeneity; ranging from negligible to extreme hypertrophy, absent or severe left ventricular outflow tract obstruction, normal longevity or premature sudden cardiac death (SCD), even in patients carrying the same pathogenic HCM mutation. Since the introduction of HCM as a clinical entity in 1958, extensive research has been performed regarding diagnosis, prognosis, therapy and genetics. However, correct diagnosis and optimal management of HCM patients and their asymptomatic affected family members still offers difficulties to the physician. This thesis describes the findings of HCM patients followed at the ErasmusMC in Rotterdam for years. It is directed towards the different pheno- and genotypical aspects of this disease. Furthermore results of basic sarcomere investigations, pathophysiologic characteristics to explain clinical findings, therapeutic measures both with and without surgery and natural history are described

Gender and cultural influences upon career choices in science and mathematics

The purpose of this paper is to synthesize and analyze the research literature related to the relationship of gender and cultural differences and the impact it may have on career choices within the science or mathematics fields. The following questions will be addressed. 1. To what extent, if any, are gender related differences identifiable in the learning of science and/or mathematics objectives? 2. What is the impact of ethnic/cultural differences on science and/or mathematics learning? 3. What is the relationship of gender or cultural differences to career choices in the science and/or mathematics field

Demixing can occur in binary hard-sphere mixtures with negative non-additivity

A binary fluid mixture of non-additive hard spheres characterized by a size ratio $\gamma=\sigma_2/\sigma_1<1$ and a non-additivity parameter $\Delta=2\sigma_{12}/(\sigma_1+\sigma_2)-1$ is considered in infinitely many dimensions. From the equation of state in the second virial approximation (which is exact in the limit $d\to\infty$) a demixing transition with a critical consolute point at a packing fraction scaling as $\eta\sim d 2^{-d}$ is found, even for slightly negative non-additivity, if $\Delta>-{1/8}(\ln\gamma)^2$. Arguments concerning the stability of the demixing with respect to freezing are provided.Comment: 4 pages, 2 figures; title changed; final paragraph added; to be published in PRE as a Rapid Communicatio

Anti-pheromone as a tool for better exploration of search space

Many animals use chemical substances known as pheromones to induce behavioural changes in other members of the same species. The use of pheromones by ants in particular has lead to the development of a number of computational analogues of ant colony behaviour including Ant Colony Optimisation. Although many animals use a range of pheromones in their communication, ant algorithms have typically focused on the use of just one, a substance that encourages succeeding generations of (artificial) ants to follow the same path as previous generations. Ant algorithms for multi-objective optimisation and those employing multiple colonies have made use of more than one pheromone, but the interactions between these different pheromones are largely simple extensions of single criterion, single colony ant algorithms. This paper investigates an alternative form of interaction between normal pheromone and anti-pheromone. Three variations of Ant Colony System that apply the anti-pheromone concept in different ways are described and tested against benchmark travelling salesman problems. The results indicate that the use of anti-pheromone can lead to improved performance. However, if anti-pheromone is allowed too great an influence on ants' decisions, poorer performance may result

Ageing effects around the glass and melting transitions in poly(dimethylsiloxane) visualized by resistance measurements

The process of ageing in rubbers requires monitoring over long periods (days to years). To do so in non-conducting rubbers, small amounts of carbon-black particles were dispersed in a fractal network through the rubber matrix, to make the rubber conducting without modifying its properties. Continuous monitoring of the resistance reveals the structural changes around the glass and melting transitions and especially details about the hysteresis and ageing processes. We illustrate the method for the semicrystalline polymer poly(dimethylsiloxane) (PDMS).Comment: 4 pages, 4 figure

The causal effect of red blood cell folate on genome-wide methylation in cord blood: a Mendelian randomization approach

Background: Investigation of the biological mechanism by which folate acts to affect fetal development can inform appraisal of expected benefits and risk management. This research is ethically imperative given the ubiquity of folic acid fortified products in the US. Considering that folate is an essential component in the one-carbon metabolism pathway that provides methyl groups for DNA methylation, epigenetic modifications provide a putative molecular mechanism mediating the effect of folic acid supplementation on neonatal and pediatric outcomes. Results: In this study we use a Mendelian Randomization Unnecessary approach to assess the effect of red blood cell (RBC) folate on genome-wide DNA methylation in cord blood. Site-specific CpG methylation within the proximal promoter regions of approximately 14,500 genes was analyzed using the Illumina Infinium Human Methylation27 Bead Chip for 50 infants from the Epigenetic Birth Cohort at Brigham and Women’s Hospital in Boston. Using methylenetetrahydrofolate reductase genotype as the instrument, the Mendelian Randomization approach identified 7 CpG loci with a significant (mostly positive) association between RBC folate and methylation level. Among the genes in closest proximity to this significant subset of CpG loci, several enriched biologic processes were involved in nucleic acid transport and metabolic processing. Compared to the standard ordinary least squares regression method, our estimates were demonstrated to be more robust to unmeasured confounding. Conclusions: To the authors’ knowledge, this is the largest genome-wide analysis of the effects of folate on methylation pattern, and the first to employ Mendelian Randomization to assess the effects of an exposure on epigenetic modifications. These results can help guide future analyses of the causal effects of periconceptional folate levels on candidate pathways

Solwind observations of coronal mass ejections during 1979-1985

Coronal observations have been processed for parts of each year during the interval 1979-1985. Around sunspot maximum, coronal mass ejections (CMEs) occurred at the rate of approximately 2 per day, and had a wide range of physical and morphological properties. During the recent years of relatively low sunspot number, CMEs occurred at the rate of only 0.2 per day, and were dominated by the class of so-called streamer blowout. These special CMEs maintained a nearly constant occurrence rate of roughly 0.1 per day during the entire interval