Tidal stripping as a mechanism for placing globular clusters on wide orbits: the case of MGC1 in M31

The globular clusters of large spiral galaxies can be divided into two populations: one which formed in-situ and one which comprises clusters tidally stripped away from other galaxies. In this paper we investigate the contribution to the outer globular cluster population in the M31 galaxy through donation of clusters from dwarf galaxies. We test this numerically by comparing the contribution of globular clusters from simulated encounters to the observed M31 globular cluster population. To constrain our simulations, we specifically investigate the outermost globular cluster in the M31 system, MGC1. The remote location of MGC1 favours the idea of it being captured, however, the cluster is devoid of features associated with tidal interactions. Hence we separate simulations where tidal features are present and where they are hidden. We find that our simulated encounters can place clusters on MGC1-like orbits. In addition, we find that tidal stripping of clusters from dwarf galaxies leaves them on orbits having a range of separations, broadly matching those observed in M31. We find that the specific energies of globular clusters captured by M31 closely matches those of the incoming host dwarf galaxies. Furthermore, in our simulations we find an equal number of accreted clusters on co-rotating and counter-rotating orbits within M31 and use this to infer the fraction of clusters that has been accreted. We find that even close in roughly 50% of the clusters are accreted, whilst this figure increases to over 80% further out.Comment: 17 pages, 12 figures. Accepted for publication in MNRA

The design, construction and commissioning of a pilot plant for the fluidised bed combustion of gasified fuel oil

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Color and Spin in Quarkonium Production

I describe the NRQCD factorization approach to the inclusive production of heavy quarkonium, contrasting it with the color-singlet and color evaporation models. These approaches differ dramatically in their assumptions about the roles played by color and spin in the production process. They also differ dramatically in their predictions for the production of charmonium at large transverse momentum.Comment: 17 pages, LATEX with style file sprocl.st

Both action potentials and variation potentials induce proteinase inhibitor gene expression in tomato

AbstractTomato plants (Lycopersicon esculentum) accumulate proteinase inhibitor 2 (pin2) mRNA in response to insect attack, crushing and flaming in leaves distant from those treated. Most earlier work suggests that the systemic wound signals are chemical; here we try to determine whether electrical or physical (hydraulic) signals can also evoke pin expression. We used a mild flame to evoke a systemic hydraulic signal and its local electrical aftermath, the variation potential (VP), and we used an electric stimulus to evoke a systemic electrical signal, the action potential (AP). We determined the kinetic parameters of both the VP and AP. Flame-wounded plants essentially always exhibited major electrical responses throughout the plant and a several-fold increase in pin2 mRNA within 1 h. Electrically stimulated plants that generated and transmitted a signal (AP) into the analyzed leaf exhibited similarly large, rapid increases in pin2 mRNA levels. Plants which generated no signal, or signals of just a few microvolts, had unchanged levels of pin2 mRNA. Since the AP and VP both arrived in the receiving leaf before accumulation of pin2 mRNA began, we conclude that, in addition to the previously shown chemical signals, both hydraulically induced VPs and electrically induced APs are capable of evoking pin2 gene expression

European information: a guide to official sources

Fourth edition revised by Eric Davies. Originally published online by European Information AssociationA practical guide for anyone who needs to find official information about the European institutions and their activitie

The Impact of Community Co-operatives on Shopping Behaviour in Rural Communities in Scotland

This paper looks at the current position of the community retail co-operative sector in rural Scotland. It is an interesting and currently topical area of research as the Scottish Executive recently established a new agency, that will further promote co-operatives as a mechanism for increasing economic opportunities for all on a socially and environmentally sustainable basis

Studies in technical and social influences on information and library management

The works in this submission explore a specific segment of information management and the way technology and social forces, including political and legal aspects, have impinged upon it. The specific area of data protection in theory and practice was chosen as an exemplar of the many and varied influences in this context which have to some extent, changed irrevocably the manager's world. Other examples such as computer misuse, information technology health and safety implications and electronic intellectual property issues might equally have been candidates for consideration since they all embody similar combinations of technological and sociolegal components. Data protection was, however, considered worthy of treatment as it is a relatively neglected area in terms of the attention it has claimed both from practitioners and researchers. Moreover, it does neatly represent the interesting juxtaposition of broadly technical and social factors that confront the manager

Localism and the community shop

There has been considerable interest in recent years in the establishment of community retail enterprises; local shops owned and run by the local community often as an alternative to the closure of the last privately-owned shop in the area. Government efforts to give local communities more rights and powers, including a community right to bid for ‘assets of community value,' would seem to offer new opportunities for such enterprises. However, there are more barriers to the establishment and continued running of these enterprises than might appear at first sight. Community retail enterprises often need specific support from local and national organisations tailored to the different stages in their development if they are to fulfil their potential