Planetary Dynamics and Habitable Planet Formation In Binary Star Systems

Whether binaries can harbor potentially habitable planets depends on several factors including the physical properties and the orbital characteristics of the binary system. While the former determines the location of the habitable zone (HZ), the latter affects the dynamics of the material from which terrestrial planets are formed (i.e., planetesimals and planetary embryos), and drives the final architecture of the planets assembly. In order for a habitable planet to form in a binary star system, these two factors have to work in harmony. That is, the orbital dynamics of the two stars and their interactions with the planet-forming material have to allow terrestrial planet formation in the habitable zone, and ensure that the orbit of a potentially habitable planet will be stable for long times. We have organized this chapter with the same order in mind. We begin by presenting a general discussion on the motion of planets in binary stars and their stability. We then discuss the stability of terrestrial planets, and the formation of potentially habitable planets in a binary-planetary system.Comment: 56 pages, 29 figures, chapter to appear in the book: Planets in Binary Star Systems (Ed. N. Haghighipour, Springer publishing company

The Optical Instrumentation of the ATLAS Tile Calorimeter

The purpose of this Note is to describe the optical assembly procedure called here Optical Instrumentation and the quality tests conducted on the assembled units. Altogether, 65 Barrel (or LB) modules were constructed - including one spare - together with 129 Extended Barrel (EB) modules (including one spare). The LB modules were mechanically assembled at JINR (Dubna, Russia) and transported to CERN, where the optical instrumentation was performed with personnel contributed by several Institutes. The modules composing one of the two Extended Barrels (known as EBA) were mechanically assembled in the USA, and instrumented in two US locations (ANL, U. of Michigan), while the modules of the other Extended barrel (EBC) were assembled in Spain and instrumented at IFAE (Barcelona). Each of the EB modules includes a subassembly known as ITC that contributes to the hermeticity of the calorimeter; all ITCs were assembled at UTA (Texas), and mounted onto the module mechanical structures at the EB mechanical assembly locations.The Tile Calorimeter, covering the central region of the ATLAS experiment up to pseudorapidities of ±1.7, is a sampling device built with scintillating tiles that alternate with iron plates. The light is collected in wave-length shifting (WLS) fibers and is read out with photomultipliers. In the characteristic geometry of this calorimeter the tiles lie in planes perpendicular to the beams, resulting in a very simple and modular mechanical and optical layout. This paper focuses on the procedures applied in the optical instrumentation of the calorimeter, which involved the assembly of about 460,000 scintillator tiles and 550,000 WLS fibers. The outcome is a hadronic calorimeter that meets the ATLAS performance requirements, as shown in this paper

The Production and Qualification of Scintillator Tiles for the ATLAS Hadronic Calorimeter

The production of the scintillator tiles for the ATLAS Tile Calorimeter is presented. In addition to the manufacture and production, the properties of the tiles will be presented including light yield, uniformity and stability

The Kidneys and Aldosterone/Mineralocorticoid Receptor System in Salt-Sensitive Hypertension

Strong evidence supports the ability of the aldosterone/mineralocorticoid receptor (MR) system to dominate long-term blood pressure control. It is also increasingly recognized as an important mediator of cardiovascular and renal diseases, particularly in the presence of excessive salt intake. In a subgroup of individuals with metabolic syndrome, adipocyte-derived aldosterone-releasing factors cause inappropriate secretion of aldosterone in the adrenal glands during salt loading, resulting in the development of salt-induced hypertension and cardiac and renal damage. On the other hand, emerging data reveal that aldosterone is not a sole regulator of MR activity. We have identified the signaling crosstalk between MR and small GTPase Rac1 as a novel pathway to facilitate MR signaling. Such a local control system for MR can also be relevant to the pathogenesis of salt-sensitive hypertension, and future studies will clarify the detailed mechanism for the intricate regulation of the aldosterone/MR cascade

Sensitisation of TRPV4 by PAR2 is independent of intracellular calcium signalling and can be mediated by the biased agonist neutrophil elastase

Proteolytic activation of protease-activated receptor 2 (PAR2) may represent a major mechanism of regulating the transient receptor potential vanilloid 4 (TRPV4) non-selective cation channel in pathophysiological conditions associated with protease activation (e.g. during inflammation). To provide electrophysiological evidence for PAR2-mediated TRPV4 regulation, we characterised the properties of human TRPV4 heterologously expressed in Xenopus laevis oocytes in the presence and absence of co-expressed human PAR2. In outside-out patches from TRPV4 expressing oocytes, we detected single-channel activity typical for TRPV4 with a single-channel conductance of about 100 pS for outward and 55 pS for inward currents. The synthetic TRPV4 activator GSK1016790A stimulated TRPV4 mainly by converting previously silent channels into active channels with an open probability of nearly one. In oocytes co-expressing TRPV4 and PAR2, PAR2 activation by trypsin or by specific PAR2 agonist SLIGRL-NH2 potentiated the GSK1016790A-stimulated TRPV4 whole-cell currents several fold, indicative of channel sensitisation. Pre-incubation of oocytes with the calcium chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA)-AM did not reduce the stimulatory effect of PAR2 activation on TRPV4, which indicates that the effect is independent of intracellular calcium signalling. Neutrophil elastase, a biased agonist of PAR2 that does not induce intracellular calcium signalling, also caused a PAR2-dependent sensitisation of TRPV4. The Rho-kinase inhibitor Y27362 abolished elastase-stimulated sensitisation of TRPV4, which indicates that Rho-kinase signalling plays a critical role in PAR2-mediated TRPV4 sensitisation by the biased agonist neutrophil elastase. During acute inflammation, neutrophil elastase may sensitise TRPV4 by a mechanism involving biased agonism of PAR2 and activation of Rho-kinase

Grading mitral regurgitation using 4D flow CMR: comparison to transthoracic echocardiography

Abstract Funding Acknowledgements Type of funding sources: None. BACKGROUND Mitral Regurgitation (MR) is currently primarily assessed using multiple transthoracic echocardiography (TTE) parameters. Two-dimensional Cardiac Magnetic Resonance (CMR) can be used in difficult cases but has limited agreement with TTE for quantifying MR. We hypothesized that 4D Flow CMR may help to quantify MR. OBJECTIVES To determine the 4D Flow CMR thresholds that achieve the best agreement with TTE for grading MR. METHODS  We conducted a single-center prospective study of patients evaluated for chronic primary MR in 2016-2020. MR was evaluated blindly by TTE and 4D Flow CMR respectively by two cardiologists and two radiologists with decades of experience. MR was graded with both methods as mild, moderate or severe. 4D Flow CMR measurements included MR regurgitant volume per beat (RV) and mitral anterograde flow per beat (MF). RF was obtained as the ratio RV/MF. Additionally, MF was compared to left ventricular stroke volume (LVSV) by cine-CMR. RESULTS  We included 33 patients in the initial cohort and 33 in the validation cohort. Inter-observer agreement was good for TTE and excellent for 4D Flow CMR. Agreement between MF and LVSV was excellent. Using recommended TTE thresholds (30 mL, 60 mL, 30%, 50%), agreement was moderate for RV and RF. The best agreement between 4D Flow CMR and TTE was obtained with CMR thresholds of 20 mL and 40 mL for RV (κ=0.93; 95%CI, 0.8-1) and 20% and 37% for RF (κ=0.90; 95%CI, 0.7-0.9). In the validation cohort, agreement between TTE and 4D Flow CMR was good with the optimal thresholds (κ= 0.78; 95%CI, 0.61-0.94). CONCLUSION We propose CMR thresholds that provide a good agreement between TTE and CMR for grading MR. Further studies are needed to fully validate 4D-Flow CMR accuracy for primary MR quantification. </jats:sec

Design and Implementation of the MESH Services Platform

Industry acceptance of TINA (Telecommunications Information Networking Architecture) will depend heavily on both the evaluation of working systems that implement this architecture, and on the experiences obtained during the design and implementation of these systems. During the MESH j (Multimedia services on the Electronic Super Highway) project, a TINA based platform for networked multimedia services has been developed and evaluated. This platform, referred to as the MESH platform, implements major parts of the TINA Service Architecture version 5.0 and the TINA Network Architecture version 3.0. In addition, several demonstration services such as multiparty high-quality audio and video conferencing, shared database access and subscription management services have been created. To support the design and implementation of the MESH platform a DSC (Distributed Software Component) framework has been developed. This framework is a generalization and implementation of the TINA computation..