The Tully-Fisher and mass-size relations from halo abundance matching

The Tully-Fisher relation (TFR) expresses the connection between rotating galaxies and the dark matter haloes they inhabit, and therefore contains a wealth of information about galaxy formation. We construct a general framework to investigate whether models based on halo abundance matching are able to reproduce the observed stellar mass TFR and mass-size relation (MSR), and use the data to constrain galaxy formation parameters. Our model tests a range of plausible scenarios, differing in the response of haloes to disc formation, the relative angular momentum of baryons and dark matter, the impact of selection effects, and the abundance matching parameters. We show that agreement with the observed TFR puts an upper limit on the scatter between galaxy and halo properties, requires weak or reversed halo contraction, and favours selection effects that preferentially eliminate fast-rotating galaxies. The MSR constrains the ratio of the disc to halo specific angular momentum to be approximately in the range 0.6-1.2. We identify and quantify two problems that models of this nature face. (1) They predict too large an intrinsic scatter for the MSR, and (2) they predict too strong an anticorrelation between the TFR and MSR residuals. We argue that resolving these problems requires introducing a correlation between stellar surface density and enclosed dark matter mass. Finally, we explore the expected difference between the TFRs of central and satellite galaxies, finding that in the favoured models this difference should be detectable in a sample of ~700 galaxies.Comment: 27 pages, 10 figures; revised to match published MNRAS versio

"They Punish Murderers, Thieves, Traitors and Sorcerers": Aboriginal Criminal Justice as Reported by Early French Observers

A common theme in the writings of European explorers, historians, and religious emissaries who were among the first to comment on the inhabitants of the western hemisphere was the absence in Aboriginal society of any concept of law. In some cases these early commentators may not have interpreted what they saw correctly, and they used French words with specific legal definitions that were not relevant in the context of the behaviour they attempted to describe. Evidence from their writings, especially those of the Jesuits, shows that there was in fact law among the Native peoples of the northeast, and particularly criminal law, albeit of a different kind and process than French law. In France, with retribution or deterrence as the objective of the judicial system, the individual alone was responsible for his or her actions and suffered punishment accordingly. In contrast, apart from cases of sorcery or betrayal, which were punishable by death, Aboriginal justice sought to restore social cohesion and harmony among the group by restitution, which was a collective responsibility.L’absence de tout concept de droit dans la société autochtone est un thème récurrent des écrits des explorateurs, historiens et émissaires religieux européens, qui furent parmi les premiers à commenter le mode de vie des habitants de l’hémisphère ouest. Dans certains cas, ces premiers commentateurs ont peut-être mal interprété ce qu’ils ont vu et ils utilisaient des termes français à définition juridique précise ne s’appliquant pas, dans le contexte, au comportement qu’ils tentaient de décrire. Leurs écrits, surtout ceux des Jésuites, révèlent que le droit existait bel et bien chez les peuples autochtones du Nord-Est, surtout une justice pénale, bien que d’un type et aux mécanismes différents de ceux du droit français. En France, la rétribution et la dissuasion étant l’objectif du système judiciaire, la personne était seule responsable de ses actes et se voyait infliger des peines correspondantes. En revanche, hormis les cas de sorcellerie ou de trahison, passibles de mort, la justice autochtone cherchait à restaurer la cohésion et l’harmonie sociales au sein du groupe par la restitution, ce qui était une responsabilité collective

Accurate and efficient spin integration for particle accelerators

Accurate spin tracking is a valuable tool for understanding spin dynamics in particle accelerators and can help improve the performance of an accelerator. In this paper, we present a detailed discussion of the integrators in the spin tracking code gpuSpinTrack. We have implemented orbital integrators based on drift-kick, bend-kick, and matrix-kick splits. On top of the orbital integrators, we have implemented various integrators for the spin motion. These integrators use quaternions and Romberg quadratures to accelerate both the computation and the convergence of spin rotations. We evaluate their performance and accuracy in quantitative detail for individual elements as well as for the entire RHIC lattice. We exploit the inherently data-parallel nature of spin tracking to accelerate our algorithms on graphics processing units.Comment: 43 pages, 17 figure

Advantages of 3D time-of-flight range imaging cameras in machine vision applications

Machine vision using image processing of traditional intensity images is in wide spread use. In many situations environmental conditions or object colours or shades cannot be controlled, leading to difficulties in correctly processing the images and requiring complicated processing algorithms. Many of these complications can be avoided by using range image data, instead of intensity data. This is because range image data represents the physical properties of object location and shape, practically independently of object colour or shading. The advantages of range image processing are presented, along with three example applications that show how robust machine vision results can be obtained with relatively simple range image processing in real-time applications

Montana Tribal Courts: Influencing the Development of Contemporary Indian Law

Montana Tribal Courts: Influencing the Development of Contemporary Indian La

Montana Tribal Courts: Influencing the Development of Contemporary Indian Law

Montana Tribal Courts: Influencing the Development of Contemporary Indian La

The Skn7 Response Regulator of \u3ci\u3eSaccharomyces cerevisiae\u3c/i\u3e Interacts with Hsf1 In Vivo and Is Required for the Induction of Heat Shock Genes by Oxidative Stress

The Skn7 response regulator has previously been shown to play a role in the induction of stress-responsive genes in yeast, e.g., in the induction of the thioredoxin gene in response to hydrogen peroxide. The yeast Heat Shock Factor, Hsf1, is central to the induction of another set of stress-inducible genes, namely the heat shock genes. These two regulatory trans-activators, Hsf1 and Skn7, share certain structural homologies, particularly in their DNA-binding domains and the presence of adjacent regions of coiled-coil structure, which are known to mediate protein–protein interactions. Here, we provide evidence that Hsf1 and Skn7 interact in vitro and in vivo and we show that Skn7 can bind to the same regulatory sequences as Hsf1, namely heat shock elements. Furthermore, we demonstrate that a strain deleted for the SKN7 gene and containing a temperature-sensitive mutation in Hsf1 is hypersensitive to oxidative stress. Our data suggest that Skn7 and Hsf1 cooperate to achieve maximal induction of heat shock genes in response specifically to oxidative stress. We further show that, like Hsf1, Skn7 can interact with itself and is localized to the nucleus under normal growth conditions as well as during oxidative stress