Non-Gaussian bivariate modelling with application to atmospheric trace-gas inversion

Atmospheric trace-gas inversion is the procedure by which the sources and sinks of a trace gas are identified from observations of its mole fraction at isolated locations in space and time. This is inherently a spatio-temporal bivariate inversion problem, since the mole-fraction field evolves in space and time and the flux is also spatio-temporally distributed. Further, the bivariate model is likely to be non-Gaussian since the flux field is rarely Gaussian. Here, we use conditioning to construct a non-Gaussian bivariate model, and we describe some of its properties through auto- and cross-cumulant functions. A bivariate non-Gaussian, specifically trans-Gaussian, model is then achieved through the use of Box--Cox transformations, and we facilitate Bayesian inference by approximating the likelihood in a hierarchical framework. Trace-gas inversion, especially at high spatial resolution, is frequently highly sensitive to prior specification. Therefore, unlike conventional approaches, we assimilate trace-gas inventory information with the observational data at the parameter layer, thus shifting prior sensitivity from the inventory itself to its spatial characteristics (e.g., its spatial length scale). We demonstrate the approach in controlled-experiment studies of methane inversion, using fluxes extracted from inventories of the UK and Ireland and of Northern Australia.Comment: 45 pages, 7 figure

Worker participation & employee involvement - a comparative study

Traditionally, worker participation systems in most countries have been promoted by labour movements. This was done for both ideological and practical reasons. Worker participation, or industrial democracy, has been conceived as a means of democratising workplaces as well as of realising both intrinsic and extrinsic work values. This paper explores the experiences of two different forms of worker participation or employee involvement/empowerment schemes operating in two of Malta's leading enterprises: Malta Drydocks (MDD), an old ship-repair, state-owned company; and Micro-Malta (MM), the pseudonym for the local subsidiary of a foreign company producing micro-electronic components.peer-reviewe

The rise and fall of the COX-2 inhibitors

Non-steroidal anti-inflammatory drugs (NSAIDs) are one of the most widely prescribed groups of medicines in clinical practice, their antiinflammatory, analgesic and anti-pyretic properties making them central to the management of osteoarthritis and rheumatoid arthritis. Gastro-intestinal toxicity represents some of the mostserious adverse drug reactions of this class of drugs. In an attempt to minimize these side-effects, selective cyclo-oxygenase-2 (COX-2) inhibitors were developed. In light of increasing concerns regarding their safety, two COX-2 inhibitors – rofecoxib and valdecoxib were withdrawn from the market in September 2004 and April 2005 respectively. Various restrictions have been also imposed on all the other selective COX-2 Inhibitors.peer-reviewe

Alienation, anomie and traditional powerlessness

For many centuries the Maltese people were powerless in determining their national, political and economic matters. Powerlessness here refers to a social condition which is beyond the control of certain actors whose lives are determined by it in important respects. This "national powerlessness" was psychologically compensated by a high emotional investment in "local" institutions which, in a sense, provided the people with alternative sources of power and prestige. To an extent, these "safety valve" institutions distracted the people's attentions from national struggles for control in vital areas which were beyond their reach. In this context, the objective powerlessness is also accompanied by a subjective, normative acceptance of that condition. This does not exclude some dormant, cultural aspirations for control even in the national areas. In fact, such aspirations emerging from whatever source may gain popularity during periods of unrest due to unusual economic deprivation or manifest political repression. For the most part, however, there are few, if any, signs of a challenge to the existing national power structure. On the contrary, the prevailing interactions between the dominant and subordinate actors tend towards an apparent authority rather than a power relationship.peer-reviewe

The 'economic' orientations of Maltese migrants in London : work, money and social status

Migration and the pursuit of 'economic' advantages are generally considered to be closely related. The migrant aspires to a wider range of opportunities available with regard to his work and financial benefits. In Malta, this relationship has been traditionally' emphasized by the proponents of emigration as a remedy to the Island's chronic problem of overpopulation and scarce' economic' resources. In his study of Maltese migration during the nineteenth century, C. A. Price contends that the principal factors affecting the scale of migration at that time were 'economic'. Successive periods of poverty at home sometimes drove the Maltese overseas while at other times they were attracted by boom conditions abroad. Such an attitude towards migration has persisted throughout the present century and has received a new emphasis from both the proponents and the opponents of migration since World War n.peer-reviewe

Photosensitivity : light, sun and pharmacy

Light has a profound effect on us. We may not be conscious enough as regards the existences of many phototoxic substances and chemicals. A phototoxic substance is a chemical compound which becomes toxic when exposed to light. Phototoxicity may be manifested in various ways. Proper use of sunscreens may play a vital role in the prevention of many such reactions.peer-reviewe

A group of young Maltese workers in Britain : some sociological observations

The fieldwork on which this article is based was conducted during December 1966. It is part of a series of preliminary investigations carried out by the author which subsequently led him to a more extensive study of the Maltese migrants in London. The main hypothesis being explored concerned the extent to which the socio-cultural background of the Maltese migrants structures their patterns of behaviour in their new environment. The present article is mainly a descriptive account of the author's observations containing practically no attempt at analysis.peer-reviewe

Worker participation and employee empowerment : a comparative study of two enterprises in Malta

A recent European survey on 'New Technology and the Role of Employee Involvement' has found that "The existing pattern of involvement inside enterprises seems to be favouring participation as an agent for efficiency rather than as an agent for redistributing power". That study has noted that management is really 'interested in developing direct forms of participation with individual employees, sidestepping collective participation with employee representatives'. The actual dynamics of any participation strategy are best tested through empirical case studies. This paper explores the contrasting experiences of different forms of worker participation or employee empowerment operating in two of Malta's leading enterprises: the Drydocks (MDD) and the local subsidiary of SGS Thompson (ST) a French - Italian multinational producing electronic components.peer-reviewe

The development of personnel management

The role of personnel management in industry is as old as the industrial revolution. In the words of F.W. Taylor "the duty of enforcing the adoption of standards and of enforcing cooperation (among workmen) rests with the management alone". It was in 1899 that Taylor explained the 'science of shovelling' as a result of which a workman was taught to shovel forty-seven tons of pig iron daily instead of merely twelve and a half tons. It is well known how every aspect ofthis simple job was controlled in detail by management so as to achieve the desired results. Indeed few men can be expected to survive for long under such conditions. Taylor himself has noted that' one of the very first requirements for a man who is fit to handle pig iron as a regular occupation is that he more nearly resembles an ox than any other type". Similar conclusions had been reached by Adam Smith, one hundred and fifty years earlier.peer-reviewe

The perceptions of Trade Unions by their members : a survey report on Trade Unions in Malta

The research was carried out by the WPDC and kindly sponsored by the Freidrich Ebert Foundation (Malta Office). The contribution made by Victor Aquilina, Junior Research Fellow, towards both the fieldwork and analysis phases of the project is gratefully acknowledged. An abridged version of this paper was published in South East Europe Review, Vol 3, No.3, 2000, pp. 137- 149, while a second paper based on the same findings was published in Employee Relations, Vol. 24, No.1, 2002, pp. 53-68.During the last two decades of the 20th century, trade union membership in many countries has registered a decline. This downward trend was particularly severe in France, the United Kingdom, Italy and the Netherlands (Crouch, 1992, p. 177). The 1997 ILO Report has commented on the decline of trade union power and membership relative to the workforce. Between 1975 and 1995, the overall mean percentage of union density in Europe declined from 50.1% to 43.1% (Blaschke, 2000, p. 221). If one were to exclude a number of Northern European countries - Sweden, Denmark, Finland and Belgium - where, maybe due to the presence of a union managed employment scheme the union density has increased - the mean density of the rest of Europe in 1995 would have been a paltry 32% (ibid.).peer-reviewe