Topology optimisation using level set methods and the discontinuous Galerkin method

This paper presents a topology optimisation approach that combines an adjoint-based sensitivity analysis [1] with level set methods (LSM) [2] for front propagation, and the discontinuous Galerkin (DG) symmetric interior penalty (SIP) method [3]. The problems considered in this paper will be limited to the minimum compliance design of two-dimensional linear elastic structures

Dualisation of the D=7 Heterotic String

The dualisation and the first-order formulation of the D=7 abelian Yang-Mills supergravity which is the low energy effective limit of the D=7 fully Higssed heterotic string is discussed. The non-linear coset formulation of the scalars is enlarged to include the entire bosonic sector by introducing dual fields and by constructing the Lie superalgebra which generates the dualized coset element.Comment: 20 page

Recurrent Pericarditis in Children and Adolescents

Recurrent pericarditis (RP) is a clinical syndrome characterized by recurrent attacks of acute pericardial inflammation. Prognosis quoad vitam is good, although morbidity might be significant, especially in children and adolescents. Multiple potential etiologies result in RP, in the vast majority of cases through autoimmune or autoinflammatory mechanisms. Idiopathic RP is one of the most frequent diagnoses, that requires the exclusion of all known etiologies. Therapeutic advances in the last decade have been significant with the recognition of the effectiveness of anti IL1 therapy, but a correct diagnostic and therapeutic algorithm is of key importance. Unfortunately, most of evidence comes from studies in adult patients. Here we review the etiopathogenesis, diagnosis and management of RP in pediatric patients

An effective description of Laniakea: impact on cosmology and the local determination of the Hubble constant

We propose an effective model to describe the bias induced on cosmological observables by Laniakea, the gravitational supercluster hosting the Milky Way, which was defined using peculiar velocity data from Cosmicflows-4 (CF4). The structure is well described by an ellipsoidal shape exhibiting triaxial expansion, reasonably approximated by a constant expansion rate along the principal axes. Our best fits suggest that the ellipsoid, after subtracting the background expansion, contracts along the two smaller axes and expands along the longest one, predicting an average expansion of $\sim -1.1 ~\rm{km}/\rm{s}/\rm{Mpc}$. The different expansion rates within the region, relative to the mean cosmological expansion, induce line-of-sight-dependent corrections in the computation of luminosity distances. We apply these corrections to two low-redshift datasets: the Pantheon+ catalog of type Ia Supernovae (SN~Ia), and 63 measurements of Surface Brightness Fluctuations (SBF) of early-type massive galaxies from the MASSIVE survey. We find corrections on the distances of order $\sim 2-3\%$, resulting in a shift in the inferred best-fit values of the Hubble constant $H_0$ of order $\Delta H_0^{\rm{SN~Ia}}\approx 0.5 ~\rm{km}/\rm{s}/\rm{Mpc}$ and $\Delta H_0^{\rm{SBF}}\approx 1.1 ~\rm{km}/\rm{s}/\rm{Mpc}$, seemingly worsening the Hubble tension.Comment: Updated to match the published version. Eighteen pages + references, 13 figures, 1 appendix, title and abstract slightly changed. Comments are welcome

Dualisation of the General Scalar Coset in Supergravity Theories

The dualised formulation of the symmetric space sigma model is peformed for a general scalar coset G/K where G is a maximally non-compact group and K is it's maximal compact subgroup.By using the twisted self-duality condition the general form of the first-order equations are obtained.The results are applied to the example of SL(2,R)/SO(2) scalar manifold of the IIB supergravity.Comment: 22 page

Effects of Enriched Environment (EE) on Depressive-Like Behavior and Hippocampal Structure in Rat Model of Chronic Stress

Chronic stress is associated with the development of depression. It can trigger structural and neurobehavioral changes in the brain and has been shown to induce depressivelike behavior in animals. An enriched environment can modulate the structure and function of the brain by altering the expression of various genes and proteins as well as affecting neurotransmitters’ activity. The hippocampus plays an important role incontrolling the networks for mood regulation and has been implicated in the course of depression. This study aimed to investigate the effect of an enriched environment on the depressive-like behavior and hippocampal structure in rats after unpredictable chronic mild stress (UCMS) exposure. Male Wistar rats (Rattus novergicus) were divided into three groups, each consisting of 6 rats including the control, UCMS and UCMS+EEgroup. Unpredictable chronic mild stress and EE were given for 21 days. Body weight gain, depressive-like behavior, and hippocampal structure were evaluated at the end of the experiment. Depressive-like behavior was assessed with Forced Swim Test (FST) and Sucrose Preference Test (SPT). Thickness of the pyramidal layer of CA1 and CA3 area were measured with histologic examination to see changes in the hippocampalstructure. Data were analyzed using One-Way ANOVA or Kruskal-Wallis followed by multiple comparison post hoc test. The enriched environment could significantly maintain body weight gain (p = 0.036) and rat’s preference to sucrose solution (p =0.001) in a stressful condition. Enriched environment reduced immobility time in FST but it was not statistically significant (p = 0.177). There was a significant difference in the thickness of CA1 and CA3 pyramidal layer of the hippocampus among groups (p=0.015 and p=0.019 respectively). Stress markedly decreased the thickness of CA1 and CA3 pyramidal layer (p=0.014 and 0.011 respectively). The enriched environment can ameliorate stress-induced depressive-like behavior and alteration in hippocampalstructure in rats. Keywords: Environmental enrichment, depression, stress, hippocampu

POS1315 USEFULNESS OF SYNOVIAL BIOPSY IN THE DIFFERENTIAL DIAGNOSIS AND AS POSSIBLE PREDICTOR OF RESPONSE TO TREATMENT IN JUVENILE IDIOPATHIC ARTHRITIS

Background:While synovial biopsy is an invasive procedure and is not required for the diagnosis of juvenile idiopathic arthritis (JIA), it may be useful in doubtful cases.Objectives:Aims of the study were i.to verify the role of synovial biopsy in the differential diagnosis of JIA and ii. to review the pathology slides in order to evaluate possible associations of a histologic pattern with response to treatment.Methods:We reviewed data from medical records of patients under the age of 18 years who underwent a synovial biopsy requested by our Pediatric Rheumatology Unit over the last 10 years. We collected information on demographic, clinical, laboratory, radiological, histopathological characteristics, as well as treatment response (in particular, remission at the last visit and number of examination, number of biologic drugs used). Among variables in the histologic score, number of layers in the synovial lining and inflammatory infiltrate (0-5) were compared to clinical status at last visit. Potential differences in variables between responders and non responders were assessed by unpaired t-test or non-parametric Mann-Whitney test, as appropriate.Results:We identified 64 patients (40F, 24M) with a median age at disease onset of 9 years (range 1-15) and a median follow-up time of 161 months (range 8-1160). We recognized two groups of interest: patients with a known JIA diagnosis (28/64) and patients with unknown diagnosis (36/64) at the moment of synovial biopsy. In the group with known JIA, most underwent the procedure during orthopedic surgery, and in all cases the histology was consistent with JIA. Among the unknown diagnosis group, in 19 cases results were consistent with a chronic synovitis, while among the other 17 histology could lead to a diagnosis of other conditions in 6 cases (foreign body and villonodular synovitis n=2 each, sarcoidosis and osteochondromatosis n=1 each). In the remaining 11 the final diagnoses were varied (mostly genetic forms eg skeletal dysplasia, CACP, Thiemann disease).Between the two groups we identified 46 patients with a definite JIA diagnosis. At the last follow-up visit 29 of them were in clinical remission, albeit on medication. The remaining 17 had a severe course of disease, with persistent activity and use of at least two biologic drugs. In 26 cases we could evaluate the correlation between status at last visit and number of layers/inflammatory infiltrate, but no statistical significant correlation was found.Conclusion:Despite its limited use nowadays, synovial biopsy may still be a useful tool in patients whose diagnosis is unclear. In our study, while it confirmed the suspicion in most cases, in other instances it allowed the diagnosis of rare conditions that would have been otherwise missed. No association between disease course and histological features in a small JIA cohort was found. We are currently expanding the study with a larger series.Disclosure of Interests:None declare

U-duality and M-Theory

This work is intended as a pedagogical introduction to M-theory and to its maximally supersymmetric toroidal compactifications, in the frameworks of 11D supergravity, type II string theory and M(atrix) theory. U-duality is used as the main tool and guideline in uncovering the spectrum of BPS states. We review the 11D supergravity algebra and elementary 1/2-BPS solutions, discuss T-duality in the perturbative and non-perturbative sectors from an algebraic point of view, and apply the same tools to the analysis of U-duality at the level of the effective action and the BPS spectrum, with a particular emphasis on Weyl and Borel generators. We derive the U-duality multiplets of BPS particles and strings, U-duality invariant mass formulae for 1/2- and 1/4-BPS states for general toroidal compactifications on skew tori with gauge backgrounds, and U-duality multiplets of constraints for states to preserve a given fraction of supersymmetry. A number of mysterious states are encountered in D<=3, whose existence is implied by T-duality and 11D Lorentz invariance. We then move to the M(atrix) theory point of view, give an introduction to Discrete Light Cone Quantization (DLCQ) in general and DLCQ of M-theory in particular. We discuss the realization of U-duality as electric-magnetic dualities of the Matrix gauge theory, display the Matrix gauge theory BPS spectrum in detail, and discuss the conjectured extended U-duality group in this scheme.Comment: 132 pages, 37 tables, Latex2e; v3: minor corrections, text reformatted, update of refs, note added about boundaries of M-theory moduli space, final version to appear in Phys. Rep

ROCKFALLS: IN SITU TEST, KINEMATIC SIMULATION AND MITIGATION MEASURES &#8211; SASSO FARINACCIO CASE STUDY

This research deals with the analysis of rockfall motion and the importance of kinematic simulations as well as in situ tests in designing of protection measures. The study area is a talus slope located in Northern Italy (Provence of Sondrio), where rockfalls frequently occur. The positions and dimensions of fallen blocks were measured and used in the calibration process, performed through the back-analysis approach. The calibrated values of restitution coefficients were compared with those obtained from in situ tests, which were carried out on the examined slope. Looking at the resulting rock fall hazard, the bidimensional kinematic simulations were performed in order to individuate the most suitable location and dimensions of mitigation measures

Lumbar epidural fentanyl: segmental spread and effect on temporal summation and muscle pain

Background. Despite extensive use, different aspects of the pharmacological action of epidural fentanyl have not been clarified. We applied a multi‐modal sensory test procedure to investigate the effect of epidural fentanyl on segmental spread, temporal summation (as a measure for short‐lasting central hyperexcitability) and muscle pain. Methods. Thirty patients received either placebo, 50 or 100 µg single dose of fentanyl epidurally (L2-3), in a randomized, double‐blind fashion. Heat pain tolerance thresholds at eight dermatomes from S1 to fifth cranial nerve (assessment of segmental spread), pain threshold to transcutaneous repeated electrical stimulation of the sural nerve (assessment of temporal summation) and pain intensity after injection of hypertonic saline into the tibialis anterior muscle (assessment of muscle pain) were recorded. Results. Fentanyl 100 µg, but not 50 µg, produced analgesia to heat stimulation only at L2. Surprisingly, no effect at S1 was detected. Both fentanyl doses significantly increased temporal summation threshold and decreased muscle pain intensity. Conclusions. The findings suggest that a single lumbar epidural dose of fentanyl should be injected at the spinal interspace corresponding to the dermatomal site of pain. Increased effect on L2 compared with S1 suggests that drug effect on spinal nerve roots and binding to opioid receptors on the dorsal root ganglia may be more important than traditionally believed for the segmental effect of epidurally injected fentanyl. Epidural fentanyl increases temporal summation threshold and could therefore contribute to prevention and treatment of central hypersensitivity states. I.M. injection of hypertonic saline is a sensitive technique for detecting the analgesic action of epidural opioids. Br J Anaesth 2003; 90: 467-7