Substructure: Clues to the Formation of Clusters of Galaxies

We have examined the spatial distribution of substructure in clusters of galaxies using Einstein X-ray observations. Subclusters are found to have a markedly anisotropic distribution that reflects the surrounding matter distribution on supercluster scales. Our results suggest a picture in which cluster formation proceeds by mergers of subclusters along large-scale filaments. The implications of such an anisotropic formation process for the shapes, orientations and kinematics of clusters are discussed briefly.Comment: 7 pages, uuencoded compressed postscript. To appear in ApJ Letters (September 20, 1995 issue

Suppression of displacement in severely slowed saccades

Severely slowed saccades in <I>spinocerebellar ataxia</I> have previously been shown to be at least partially closed-loop in nature: their long duration means that they can be modified in-flight in response to intrasaccadic target movements. In this study, a woman with these pathologically slowed saccades could modify them in-flight in response to target movements, even when saccadic suppression of displacement prevented conscious awareness of those movements. Thus saccadic suppression of displacement is not complete, in that it provides perceptual information that is sub-threshold to consciousness but which can still be effectively utilised by the oculomotor system

N-Person cake-cutting: there may be no perfect division

A cake is a metaphor for a heterogeneous, divisible good, such as land. A perfect division of cake is efficient (also called Pareto-optimal), envy-free, and equitable. We give an example of a cake in which it is impossible to divide it among three players such that these three properties are satisfied, however many cuts are made. It turns out that two of the three properties can be satisfied by a 3-cut and a 4-cut division, which raises the question of whether the 3-cut division, which is not efficient, or the 4-cut division, which is not envy-free, is more desirable (a 2-cut division can at best satisfy either envy-freeness or equitability but not both). We prove that no perfect division exists for an extension of the example for three or more players.Cake-cutting; fair division; efficiency; envy-freeness; equitability; heterogeneous good

How do Multinationals Build Social Capital? Diageo's Corporate Citizenship Programme.

This paper attempts to enhance understanding of the process by which multinationals build social capital by examining the Corporate Citizenship (CC) activities and associated social capital outcomes of the UK-based branded alcoholic drinks company, Diageo. The firm possesses a structured portfolio of CC initiatives and projects and has a long-standing tradition of community engagement. This paper examines Diageo’s CC strategy in depth and considers the ways that their engagements impact upon social capital development in different arenas. The forces driving social capital outcomes are considered and implications for companies and governments are offered.social capital, corporate citizenship, Diageo, community programmes.

Forming Stable Coalitions: The Process Matters

Players are assumed to rank each other as coalition partners. Two processes of coalition formation are defined and illustrated: i) Fallback (FB): Players seek coalition partners by descending lower and lower in their preference rankings until some majority coalition, all of whose members consider each other mutually acceptable, forms. ii) Build-up (BU):Same descent as FB, except only majorities whose members rank each other highest form coalitions. BU coalitions are stable in the sense that no member would prefer to be in another coalition, whereas FB coalitions, whose members need not rank each other highest, may not be stable. BU coalitions are bimodally distributed in a random society, with peaks around simple majority and unanimity the distributions of majorities in the US Supreme Count and in the US House of Representatives follow this pattern. The dynamics of real-life coalition-formation processes are illustrated by two Supreme Court cases.Coalition dynamics, Fallback bargaining, Manipulability, Legislatures, US Supreme Court

The Clustering Of Galaxies Around Radio-Loud AGNs

We examine the hypothesis that mergers and close encounters between galaxies can fuel AGNs by increasing the rate at which gas accretes towards the central black hole. We compare the clustering of galaxies around radio-loud AGNs with the clustering around a population of radio-quiet galaxies with similar masses, colors and luminosities. Our catalog contains 2178 elliptical radio galaxies with flux densities greater than 2.8 mJy at 1.4 GHz from the 6dFGS survey. We find that radio AGNs with more than 200 times the median radio power have, on average, more close (r<160 kpc) companions than their radio-quiet counterparts, suggestive that mergers play a role in forming the most powerful radio galaxies. For ellipticals of fixed stellar mass, the radio power is not a function of large-scale environment nor halo mass, consistent with the radio powers of ellipticals varying by orders of magnitude over billions of years.Comment: 12 pages, 6 figure