The DSR-deformed relativistic symmetries and the relative locality of 3D quantum gravity

Over the last decade there were significant advances in the understanding of quantum gravity coupled to point particles in 3D (2+1-dimensional) spacetime. Most notably it is emerging that the theory can be effectively described as a theory of free particles on a momentum space with anti-deSitter geometry and with noncommutative spacetime coordinates of the type $[x^{\mu},x^{\nu}]=i \hbar \ell \varepsilon^{\mu\nu}_{\phantom{\mu\nu}\rho} x^{\rho}$. We here show that the recently proposed relative-locality curved-momentum-space framework is ideally suited for accommodating these structures characteristic of 3D quantum gravity. Through this we obtain an intuitive characterization of the DSR-deformed Poincar\'e symmetries of 3D quantum gravity, and find that the associated relative spacetime locality is of the type producing dual-gravity lensing.Comment: LaTex, 12 pages, 3 figure

On the interplay between multiscaling and stocks dependence

We find a nonlinear dependence between an indicator of the degree of multiscaling of log-price time series of a stock and the average correlation of the stock with respect to the other stocks traded in the same market. This result is a robust stylized fact holding for different financial markets. We investigate this result conditional on the stocks' capitalization and on the kurtosis of stocks' log-returns in order to search for possible confounding effects. We show that a linear dependence with the logarithm of the capitalization and the logarithm of kurtosis does not explain the observed stylized fact, which we interpret as being originated from a deeper relationship.Comment: 19 pages, 8 figures, 9 table

Model-based aerodynamic-angle attitude control of an atmospheric entry capsule

The paper describes the attitude control system of a low lift-to-drag biconic atmospheric entry capsule based on the Embedded Model Control methodology. The control structure derives from the development of the attitude dynamics and kinematics written in terms of aerodynamic angles, instead of Euler/quaternion kinematics. A detailed development of the simplified set of equations linking the torques generated by the reaction control system with the time evolution of the aerodynamic angles is provided. The simplified set of equations becomes the core of the control algorithm. The bank angle dynamics is shown to be fourthorder and forced by yaw and roll torques. A dynamic dispatching technique is proposed for converting fourth-order dynamics into a pair of second order systems. Nonlinear dynamic inversion and active disturbance rejection are employed to handle gyroscopic torques, parametric errors and to compensate for angular variation of translational velocity. A bank reversal logic is designed to reduce the effect of bank reversals on the translational motion. The performance of the attitude control algorithm has been tested on a high fidelity simulator and relevant results are presented

Visual control through narrow passages for an omnidirectional wheeled robot

Robotic systems are gradually replacing human intervention in dangerous facilities to improve human safety and prevent risky situations. In this domain, our work addresses the problem of autonomous crossing narrow passages in a semi-structured (i.e., partially-known) environment. In particular, we focus on the CERN’s Super Proton Synchrotron particle accelerator, where a mobile robot platform is equipped with a lightweight arm to perform measurements, inspection, and maintenance operations. The proposed approach leverages an image-based visual servoing strategy that exploits computer vision to detect and track known geometries defining narrow passage gates. The effectiveness of the proposed approach has been demonstrated in a realistic mock-up

Missplicing due to a synonymous, T96= exonic substitution in the T-box transcription factor TBX19 resulting in isolated ACTH deficiency

Congenital isolated ACTH deficiency (IAD) is a rare condition characterised by low plasma ACTH and serum cortisol with normal production of other pituitary hormones. TBX19 (also known as TPIT) is a T-box pituitary restricted transcription factor important for POMC gene transcription and terminal differentiation of POMC-expressing cells. TBX19 gene mutations have been shown to cause neonatal-onset congenital IAD. We report a neonate of Romanian origin, who presented at 15 h of life with respiratory arrest and hypoglycaemia which recurred over the following 2 weeks. Biochemical investigations revealed IAD, with undetectable serum cortisol (cortisol < 1 μg/dL; normal range (NR): 7.8–26.2) and plasma ACTH levels within the normal range (22.1 pg/mL; NR: 4.7–48.8). He responded to hydrocortisone treatment. Patient DNA was analysed by a HaloPlex next-generation sequencing array targeting genes for adrenal insufficiency. A novel homozygous synonymous mutation p.Thr96= (Chr1:168260482; c.288G>A; rs376493164; allele frequency 1 × 10−5, no homozygous) was found in exon 2 of the TBX19 gene. The effect of this was assessed by an in vitro splicing assay, which revealed aberrant splicing of exon 2 giving rise to a mutant mRNA transcript whereas the WT vector spliced exon 2 normally. This was identified as the likely cause of IAD in the patient. The predicted protein product would be non-functional in keeping with the complete loss of cortisol production and early presentation in the patient

CD4 homologue in sea bass (Dicentrarchus labrax): molecular characterization and structural analysis

CD4 is a transmembrane glycoprotein fundamental for cell-mediated immunity. Its action as a T cell coreceptor increases the avidity of association between a T cell and an antigen-presenting cell by interacting with portions of the complex between MHC class II and TR molecules. In this paper we report the cDNA cloning, expression and structural analysis of a CD4 homologue from sea bass (Dicentrarchus labrax). The sea bass CD4 cDNA consists of 2071 bp that translates in one reading frame to give the entire molecule containing 480 amino acids. The analysis of the sequence shows the presence of four putative Ig-like domains and that some fundamental structural features, like a disulphide bond in domain D2 and the CXC signalling motif in the cytoplasmic tail, are conserved from sea bass to mammals. Real-time PCR analysis showed that very high levels of CD4 mRNA transcripts are present in thymus, followed by gut and gills. In vitro stimulation of head kidney leukocytes with LPS and PHA-L gave an increase of CD4 mRNA levels after 4 h and a decrease after 24 h. Homology modelling has been applied to create a 3D model of sea bass CD4 and to investigate its interaction with sea bass MHC-II. The analysis of the 3D complex between sea bass CD4 and sea bass MHC-II suggests that the absence of a disulfide bond in the CD4 D1 domain could make this molecule more flexible, inducing a different conformation and affecting the binding and the way of interaction between CD4 and MHC-II. Our results will add new insights into the sea bass T cell immune responses and will help in the identification of T cell subsets in teleost fishes to better understand the evolution of cell-mediated immunity from fish to mammals.L'articolo è disponibile sul sito dell'editore http://www.sciencedirect.com