6,519 research outputs found
Testing Bekenstein's Relativistic MOND gravity with Lensing Data
We propose to use multiple-imaged gravitational lenses to set limits on
gravity theories without dark matter, specificly TeVeS (Bekenstein 2004), a
theory which is consistent with fundamental relativistic principles and the
phenomenology of MOdified Newtonian Dynamics (MOND) theory. After setting the
framework for lensing and cosmology, we derive analytically the deflection
angle for the point lens and the Hernquist galaxy profile, and fit
galaxy-quasar lenses in the CASTLES sample. We do this with three methods,
fitting the observed Einstein ring sizes, the image positions, or the flux
ratios. In all cases we consistently find that stars in galaxies in MOND/TeVeS
provide adequate lensing. Bekenstein's toy function provides more
efficient lensing than the standard MOND function. But for a handful of
lenses [indicated in Table 2,3, fig 16] a good fit would require a lens mass
orders of magnitude larger/smaller than the stellar mass derived from
luminosity unless the modification function and modification scale
for the universal gravity were allowed to be very different from what spiral
galaxy rotation curves normally imply. We discuss the limitation of present
data and summarize constraints on the MOND function. We also show that
the simplest TeVeS "minimal-matter" cosmology, a baryonic universe with a
cosmological constant, can fit the distance-redshift relation from the
supernova data, but underpredicts the sound horizon size at the last
scattering. We conclude that lensing is a promising approach to differentiate
laws of gravity (see also astro-ph/0512425).Comment: reduced to 17p, 16 figs, discussed cosmology and constraints on
mu-function, MNRAS accepte
Segregation and Internal Weakness in Forging Ingots
The type of segregation generally known as 'A' segregation which occurs at positions between the ingot axis and the outer surface still remains a baffling problem, no means
having so far been found for its prevention.In addition to the various types of segregation and apart from primary pipe which can be easily dealt with, problems arise with
regard to secondary piping, and discontinuities and poro-sity around the top of the basal Cone
The retroflection of part of the East Greenland Current at Cape Farewell
The East Greenland Current (EGC) and the smaller East Greenland Coastal Current (EGCC) provide the major conduit for cold fresh polar water to enter the lower latitudes of the North Atlantic. They flow equatorward through the western Irminger Basin and around Cape Farewell into the Labrador Sea. The surface circulation and transport of the Cape Farewell boundary current region in summer 2005 is described. The EGCC merges with Arctic waters of the EGC to the south of Cape Farewell, forming the West Greenland Current. The EGC transport decreases from 15.5 Sv south of Cape Farewell to 11.7 Sv in the eastern Labrador Sea (where the water becomes known as Irminger Sea Water). The decrease in EGC transport is balanced by the retroflection of a substantial proportion of the boundary current (5.1 Sv) into the central Irminger Basin; a new pathway for fresh water into the interior of the subpolar gyre
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Workplace union representation in the British public sector: evidence from the 2011 Workplace Employment Relations Survey.
This paper explores the presence of workplace union representatives in the British public sector, and also the extent to which union representatives are engaged in partnership working with management, drawing on data from the Workplace Employment Relations Survey 2011. This analysis is timely given government plans to introduce reporting requirements and reserve powers to restrict public sector facility time in the Trade Union Bill 2015-16. The analysis finds that in workplaces with union recognition, union representatives are more prevalent and there are more representatives per employee in the public than the private sector, but there is no evidence that this should be viewed as excessive or that managers view it as problematic. There is, on balance, greater evidence of partnership working between union representatives and managers in the public than the private sector. Given the importance of partnership working in improving public services, the results suggest the provisions in the Trade Union Bill 2015-16 relating to public sector facility time are more likely to hinder rather than support public sector managers in their attempts to improve public service provision in the future
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Social Partnership and Political Devolution in the National Health Service: Emergence, Operation and Outcomes
This article explores the emergence, operation and outcomes of social partnership in the National Health Service (NHS) in Scotland and Wales. Social partnership emerged in the NHS following political devolution in 1998 which transferred powers to left-wing governments in Scotland and Wales. These arrangements helped improve health services, modernise industrial relations and enhance staff terms and conditions. In NHS Scotland, union participation in strategic decisions produced extensive co-operation to dismantle the internal health market, improve services, and enhance staff terms and conditions. Union participation in NHS Wales was restricted to discussing workforce issues, and although co-operation increased when Welsh governments gained enhanced legislative powers and dismantled the internal health market, it delivered fewer improvements in service and pay levels. Differences in government political positioning (against public sector marketisation) and degree of independence (with devolved administrations granted different legislative powers) help explain the operation and outcomes of social partnership
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The influence of trade union Disability Champions on employer disability policy and practice
Disability Champions are a new type of lay workplace trade union activist, whose role is to encourage employers to audit and improve disability policies and offer independent advice and guidance on disability issues to employees. Drawing on a survey of the population of Disability Champions, this article assesses Disability Champion influence on employer disability policy and practice. While the majority of Disability Champions report having had a positive impact, they report greater influence on employer willingness to conduct disability audits and to amend and improve employer equal opportunities practices with regard to disability than employer willingness to make reasonable adjustments. The analysis also identifies several factors that are likely to be important in improving Disability Champion effectiveness. Overall, the results suggest Disability Champions have the potential to enhance the ability of unions to represent disabled people and help manage disability issues within the workplace. The article makes a theoretical contribution to Disability Champion roles by further developing the âActivity-Support-Characteristicâ framework for the antecedents of new union representatives' effectiveness
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The contents of partnership agreements in Britain 1990-2007
This article assesses the contents of the majority of employer-union partnership agreements signed in Britain from 1990 to 2007. Few agreements contain the expected partnership principles and most express modest overall aims and limited ambition. Typical agreements are substantively hollow with more than one-third containing no substantive provisions; and procedurally biased, with more than four-fifths offering unions greater involvement in employersâ decisions. Partnership agreements continue the procedural bias of traditional British collective agreements representing the lowest common denominator of agreement â unions work towards the success of the enterprise in return for involvement in employersâ decisions. The implications for New Labourâs Third Way approach and the policy of encouraging voluntary partnership agreements to promote fairness at work are considered
Innovating places: a new role for âPlace differenceâ
This paper develops the idea of âplace differenceâ as a practical tool for supporting place-based social innovation. Originally developed by US sociologists, Harvey Molotch, William Freudenberg
and Krista Paulsen, âplace differenceâ provides a framework for thinking holistically about local
context, change and innovation. The âplace differenceâ model analyzes the multiple connections
between people, organizations, ideas, opportunities, cities and neighbourhoods, and how they âlash
upâ to create place-specific processes and outcomes. We explore how âplace differenceâ can be developed as a practical tool to increase understanding about local dynamics, how they can shape the
success and outcomes of interventions and how they can boost or frustrate innovation
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