Comparison between 2-D and 3-D codes in dynamical simulations of gas flow in barred galaxies

Context: One of the ways to determine the contribution of the dark halo to the gravitational potential of a galaxy is the study of non-circular (streaming) motions and the associated gas shocks in the bar region. These motions, determined by the potential in the inner parts, can break the disk-halo degeneracy. Here, two main fluid dynamical approaches have been chosen to model the non-circular motions in the bar region; a 2-D Eulerian grid code for an isothermal gas (FS2) and a 3-D smoothed particle hydrodynamic code (N-body/SPH). Aims: The aim of this paper is to compare and quantify the differences of the gas flows in rotating barred potential obtained using two different fluid dynamical approaches. We analyse the effect of using 2-D and a 3-D codes in the calculation of gas flow in barred galaxies and to which extend the results are affected by the code. To do this, we derive the velocity field and density maps for the mass model of NGC 4123 using a 3-D N-body/SPH code and compare the results to the previous 2-D Eulerian grid code results. Methods: Numerical modelling, 3-D N-body/SPH simulations Results: The global velocity field and the gas distribution is very similar in both models. The study shows that the position and strength of the shocks developed in the SPH simulations do not vary significantly compared to the results derived from the 2-D FS2 code. The largest velocity difference across the shock is 20\kms between the 2-D and 3-D fluid dynamical models. Conclusions: The results obtained in the studies deriving the dark matter content of barred galaxies using the bar streaming motions and strength and position of shocks are robust to the fluid dynamical model used. The effect of 2-D and 3-D modelling can be neglected in this type of studies.Comment: 5 pages, accepted for publication in A&

The Uncertain Future of Marriage and the Alternatives

The cultural and institutional predominance of marriage in our society has lately been challenged by two important social trends: growing dissatisfaction with or indifference to marriage on the part of those eligible to marry, and the emergence of nontraditional families headed by adults who may wish to marry but are presently excluded from doing so. This Essay argues that proactive law reformers have responded to these trends by taking two very different approaches. The first approach, “diversity of forms,” is exemplified by the cultivation of alternatives and substitutes to traditional marriage ranging from same and opposite-sex domestic partnerships and other forms of “marriage-lite” to commitment-intensive options like covenant marriage. The other approach, “equal inclusion,” emphasizes broader access to regular marriage itself, and is exemplified by the egalitarian, civil rights-focused, and deeply marriage-affirmative views of the Massachusetts Supreme Judicial Court in Goodridge v. Dep’t of Public Health. This Essay goes on to contend that although these two reform approaches are quite different, they share a common vision of how the law of marriage and coupling should be shaped by the social reality of citizens’ lives rather than by abstract traditional archetypes, leaving both approaches more-or-less on the same side in the larger culture war being waged over the future of marriage and family law. There is still potential for serious conflict, however, because although both approaches are skeptical of idealized tradition, they each remain nested in a diverse and disparate array of other aspirational norms that may lead them to threaten each other’s long-term institutional agendas

Controlled biomineralization of magnetite (Fe₃O₄) by <i>Magnetospirillum gryphiswaldense</i>

Results from a study of the chemical composition and micro-structural characteristics of bacterial magnetosomes extracted from the magnetotactic bacterial strain Magnetospirillum gryphiswaldense are presented here. Using high-resolution transmission electron microscopy combined with selected-area electron diffraction and energy dispersive X-ray microanalysis, biogenic magnetite particles isolated from mature cultures were analysed for variations in crystallinity and particle size, as well as chain character and length. The analysed crystals showed a narrow size range (∼14-67 nm) with an average diameter of 46±6.8 nm, cuboctahedral morphologies and typical Gamma type crystal size distributions. The magnetite particles exhibited a high chemical purity (exclusively Fe3O4) and the majority fall within the single-magnetic-domain range

The Fractal Properties of the Source and BEC

Using simple space-time implementation of the random cascade model we investigate numerically influence of the possible fractal structure of the emitting source on Bose-Einstein correlations between identical particles. The results are then discussed in terms of the non-extensive Tsallis statistics.Comment: LaTeX file and 2 PS files with figures, 8 pages altogether. Talk presented at the 12th Indian Summer School "Relativistic Heavy Ion Physics, Prague, Czech Republic, 30 August-3 Sept. 1999; to be published in Czech J. Phys. (1999). Some typos correcte

Deciphering nonfemtoscopic two-pion correlations in p+pp+p collisions with simple analytical models

A simple model of nonfemtoscopic particle correlations in proton-proton collisions is proposed. The model takes into account correlations induced by the conservation laws as well as correlations induced by minijets. It reproduces well the two-pion nonfemtoscopic correlations of like-sign and unlike-sign pions in proton-proton collision events at $\sqrt{s} = 900$ GeV analyzed by the ALICE Collaboration. We also argue that similar nonfemtoscopic correlations can appear in the hydrodynamic picture with event-by-event fluctuating nonsymmetric initial conditions that are typically associated with nonzero higher-order flow harmonics.Comment: 21 pages, 10 figures, misprints correcte

The Clustering of Extremely Red Objects

We measure the clustering of Extremely Red Objects (EROs) in ~8 deg^2 of the NOAO Deep Wide Field Survey Bo\"otes field in order to establish robust links between ERO z~1.2 and local galaxy z<0.1 populations. Three different color selection criteria from the literature are analyzed to assess the consequences of using different criteria for selecting EROs. Specifically, our samples are (R-K_s)>5.0 (28,724 galaxies), (I-K_s)>4.0 (22,451 galaxies) and (I-[3.6])>5.0 (64,370 galaxies). Magnitude-limited samples show the correlation length (r_0) to increase for more luminous EROs, implying a correlation with stellar mass. We can separate star-forming and passive ERO populations using the (K_s-[24]) and ([3.6]-[24]) colors to K_s=18.4 and [3.6]=17.5, respectively. Star-forming and passive EROs in magnitude limited samples have different clustering properties and host dark halo masses, and cannot be simply understood as a single population. Based on the clustering, we find that bright passive EROs are the likely progenitors of >4L^* elliptical galaxies. Bright EROs with ongoing star formation were found to occupy denser environments than star-forming galaxies in the local Universe, making these the likely progenitors of >L^* local ellipticals. This suggests that the progenitors of massive >4L^* local ellipticals had stopped forming stars by z>1.2, but that the progenitors of less massive ellipticals (down to L^*) can still show significant star formation at this epoch.Comment: 19 pages, 16 figures, 4 tables, Accepted to ApJ 27th November 201

Characterization of potential biomarkers of reactogenicity of licensed antiviral vaccines: randomized controlled clinical trials conducted by the BIOVACSAFE consortium

Funding text The authors are grateful for the vital contributions of the participating study volunteers, clinicians, nurses, and laboratory technicians at the Surrey study site. The work by Roberto Leone, laboratory technician at Humanitas Clinical and Research Center, is gratefully acknowledged. Finally, they thank Ellen Oe (GSK) for scientific writing assistance. The research leading to these results has received support from the Innovative Medicines Initiative Joint Undertaking under grant agreement n°115308, resources of which are composed of financial contribution from the European Union’s Seventh Framework Programme (FP7/2007–2013) and EFPIA companies’ in-kind contribution. The contribution of the European Commission to the Advanced Immunization Technologies (ADITEC) project (grant agreement n° 280873) is also gratefully acknowledged. Publisher Copyright: © 2019, The Author(s).Biomarkers predictive of inflammatory events post-vaccination could accelerate vaccine development. Within the BIOVACSAFE framework, we conducted three identically designed, placebo-controlled inpatient/outpatient clinical studies (NCT01765413/NCT01771354/NCT01771367). Six antiviral vaccination strategies were evaluated to generate training data-sets of pre-/post-vaccination vital signs, blood changes and whole-blood gene transcripts, and to identify putative biomarkers of early inflammation/reactogenicity that could guide the design of subsequent focused confirmatory studies. Healthy adults (N = 123; 20–21/group) received one immunization at Day (D)0. Alum-adjuvanted hepatitis B vaccine elicited vital signs and inflammatory (CRP/innate cells) responses that were similar between primed/naive vaccinees, and low-level gene responses. MF59-adjuvanted trivalent influenza vaccine (ATIV) induced distinct physiological (temperature/heart rate/reactogenicity) response-patterns not seen with non-adjuvanted TIV or with the other vaccines. ATIV also elicited robust early (D1) activation of IFN-related genes (associated with serum IP-10 levels) and innate-cell-related genes, and changes in monocyte/neutrophil/lymphocyte counts, while TIV elicited similar but lower responses. Due to viral replication kinetics, innate gene activation by live yellow-fever or varicella-zoster virus (YFV/VZV) vaccines was more suspended, with early IFN-associated responses in naïve YFV-vaccine recipients but not in primed VZV-vaccine recipients. Inflammatory responses (physiological/serum markers, innate-signaling transcripts) are therefore a function of the vaccine type/composition and presence/absence of immune memory. The data reported here have guided the design of confirmatory Phase IV trials using ATIV to provide tools to identify inflammatory or reactogenicity biomarkers.Peer reviewe

Superrevivals in the quantum dynamics of a particle confined in a finite square well potential

We examine the revival features in wave packet dynamics of a particle confined in a finite square well potential. The possibility of tunneling modifies the revival pattern as compared to an infinite square well potential. We study the dependence of the revival times on the depth of the square well and predict the existence of superrevivals. The nature of these superrevivals is compared with similar features seen in the dynamics of wavepackets in an anharmonic oscillator potential.Comment: 8 pages in Latex two-column format with 5 figures (eps). To appear in Physical Review