Interpolating the Sherrington-Kirkpatrick replica trick

The interpolation techniques have become, in the past decades, a powerful approach to lighten several properties of spin glasses within a simple mathematical framework. Intrinsically, for their construction, these schemes were naturally implemented into the cavity field technique, or its variants as the stochastic stability or the random overlap structures. However the first and most famous approach to mean field statistical mechanics with quenched disorder is the replica trick. Among the models where these methods have been used (namely, dealing with frustration and complexity), probably the best known is the Sherrington-Kirkpatrick spin glass: In this paper we are pleased to apply the interpolation scheme to the replica trick framework and test it directly to the cited paradigmatic model: interestingly this allows to obtain easily the replica-symmetric control and, synergically with the broken replica bounds, a description of the full RSB scenario, both coupled with several minor theorems. Furthermore, by treating the amount of replicas $n\in(0,1]$ as an interpolating parameter (far from its original interpretation) this can be though of as a quenching temperature close to the one introduce in off-equilibrium approaches and, within this viewpoint, the proof of the attended commutativity of the zero replica and the infinite volume limits can be obtained.Comment: This article is dedicated to David Sherrington on the occasion of his seventieth birthda

Effects of 2 or 5 consecutive exercise days on adipocyte area and lipid parameters in Wistar rats

<p>Abstract</p> <p>Background</p> <p>Exercise has been prescribed in the treatment and control of dyslipidemias and cholesterolemia, however, lipid responses to different training frequencies in hypercholesterolemic men have been inconsistent. We sought to verify if different frequencies of continuous moderate exercise (2 or 5 days/week, swimming) can, after 8 weeks, promote adaptations in adipocyte area and lipid parameters, as well as body weight and relative weight of tissues in normo and hypercholesterolemic adult male rats.</p> <p>Methods</p> <p>Normal cholesterol chow diet or cholesterol-rich diet (1% cholesterol plus 0.25% cholic acid) were freely given during 8 weeks to the rats divided in 6 experimentals groups: sedentary normal cholesterol chow diet (C); sedentary cholesterol-rich diet (H); 5× per week continuous training normal cholesterol chow diet (TC5) and cholesterol-rich diet (TH5); 2× per week continuos traning normal cholesterol chow diet (TC2) and cholesterol-rich diet (TH2).</p> <p>Results</p> <p>No changes were observed in lipid profile in normal cholesterol chow diet, but both 2 a 5 days/week exercise improved this profile in cholesterol-rich diet. Body weight gain was lower in exercised rats. Decrease in retroperitoneal and epididymal relative weights as well as reductions in adipocyte areas under all diets types were observed only in 5 days/week, while 2 days/week showed improvements mainly in cholesterol-rich diet rats.</p> <p>Conclusion</p> <p>Our results confirm the importance of exercise protocols to control dyslipidemias and obesity in rats. The effects of 5 days/week exercise were more pronounced compared with those of 2 consecutive days/week training.</p

Characterization of mycobacteria and mycobacteriophages isolated from compost at the São Paulo Zoo Park Foundation in Brazil and creation of the new mycobacteriophage Cluster U

Background: A large collection of sequenced mycobacteriophages capable of infecting a single host strain of Mycobacterium smegmatis shows considerable genomic diversity with dozens of distinctive types (clusters) and extensive variation within those sharing evident nucleotide sequence similarity. Here we profiled the mycobacterial components of a large composting system at the São Paulo zoo. Results: We isolated and sequenced eight mycobacteriophages using Mycobacterium smegmatis mc2155 as a host. None of these eight phages infected any of mycobacterial strains isolated from the same materials. The phage isolates span considerable genomic diversity, including two phages (Barriga, Nhonho) related to Subcluster A1 phages, two Cluster B phages (Pops, Subcluster B1; Godines, Subcluster B2), three Subcluster F1 phages (Florinda, Girafales, and Quico), and Madruga, a relative of phage Patience with which it constitutes the new Cluster U. Interestingly, the two Subcluster A1 phages and the three Subcluster F1 phages have genomic relationships indicating relatively recent evolution within a geographically isolated niche in the composting system. Conclusions: We predict that composting systems such as those used to obtain these mycobacteriophages will be a rich source for the isolation of additional phages that will expand our view of bacteriophage diversity and evolution

High ultraviolet C resistance of marine Planctomycetes

Planctomycetes are bacteria with particular characteristics such as internal membrane systems encompassing intracellular compartments, proteinaceous cell walls, cell division by yeast-like budding and large genomes. These bacteria inhabit a wide range of habitats, including marine ecosystems, in which ultra-violet radiation has a potential harmful impact in living organisms. To evaluate the effect of ultra-violet C on the genome of several marine strains of Planctomycetes, we developed an easy and fast DNA diffusion assay in which the cell wall was degraded with papain, the wall-free cells were embedded in an agarose microgel and lysed. The presence of double strand breaks and unwinding by single strand breaks allow DNA diffusion, which is visible as a halo upon DNA staining. The number of cells presenting DNA diffusion correlated with the dose of ultra-violet C or hydrogen peroxide. From DNA damage and viability experiments, we found evidence indicating that some strains of Planctomycetes are significantly resistant to ultra-violet C radiation, showing lower sensitivity than the known resistant Arthrobacter sp. The more resistant strains were those phylogenetically closer to Rhodopirellula baltica, suggesting that these species are adapted to habitats under the influence of ultra-violet radiation. Our results provide evidence indicating that the mechanism of resistance involves DNA damage repair and/or other DNA ultra-violet C-protective mechanism.This research was supported by the European Regional Development Fund (ERDF) through the COMPETE-Operational Competitiveness Programme and national funds through FCT-Foundation for Science and Technology, under the projects Pest-C/BIA/UI4050/2011 and PEst-C/MAR/LA0015/2013. We are grateful to Catia Moreira for helping with the extraction of the pigments.info:eu-repo/semantics/publishedVersio

Clinical assessment of DSM-IV anxiety disorders in fragile X syndrome: prevalence and characterization

Fragile X syndrome (FXS) is the most common form of inherited intellectual disability (ID). Anxiety and social withdrawal are considered core features of the FXS phenotype, yet there is limited diagnostic evidence of the prevalence of formal anxiety disorders in FXS. This study assessed the prevalence of anxiety disorders in a sample of 58 males and 39 females with FXS (ages 5.0–33.3 years). Participants’ parents completed the Anxiety Disorders Interview Schedule (ADIS-IV), a clinical interview based on DSM-IV criteria, and the Anxiety Depression and Mood Scale (ADAMS), a psychiatric disorders screening instrument normed in ID. We conducted cognitive (IQ) and autism (AUT) assessments and surveyed medication use. Despite a high rate of psychopharmacological treatment, 86.2% of males and 76.9% of females met criteria for an anxiety disorder, with social phobia and specific phobia the most commonly diagnosed. Proband status, gender, and IQ were not significantly related to any anxiety disorders, however significantly higher rates of a few anxiety disorders were found in older age and AUT groups. Significant correlations between ADIS diagnoses and ADAMS scores provided cross-validation of instruments, indicating that the ADIS is suitable for use in FXS. A greater percentage of our sample met criteria for most anxiety disorders than has been reported in other ID groups or the general population. The rate of anxiety compared to general ID suggests that the FMR1 full mutation confers an especially high risk for these disorders, regardless of factors commonly associated with FXS clinical involvement. A thorough clinical assessment and treatment of anxiety should be included in the FXS standard of care