Sustainable development, although a widely used phrase and idea, has many different meanings and therefore provokes many different responses. In broad terms, the concept of sustainable development is an attempt to combine growing concerns about a range of environmental issues with socio-economic issues. To aid understanding of these different policies this paper presents a classification and mapping of different trends of thought on sustainable development, their political and policy frameworks and their attitudes towards change and means of change. Sustainable development has the potential to address fundamental challenges for humanity, now and into the future.However, to do this, it needs more clarity of meaning, concentrating on sustainable livelihoods and well-being rather than well-having, and long term environmental sustainability, which requires a strong basis in principles that link the social and environmental to human equity. 3 Sustainable Development: Mapping Different Approaches Sustainable Development: A Challenging and Contested ConceptThe widespread rise of interest in, and support for, the concept of sustainable development is potentially an important shift in understanding relationships of humanity with nature and between people. It is in contrast to the dominant outlook of the last couple of hundred years, especially in the "North", that has been based on the view of the separation of the environment from socio-economic issues.For most of the last couple of hundred years the environment has been largely seen as external to humanity, mostly to be used and exploited, with a few special areas preserved as wilderness or parks. Environmental problems were viewed mainly as local. On the whole the relationship between people and the environment was conceived as humanity"s triumph over nature. This Promethean view (Dryzeck, 1997) was that human knowledge and technology could overcome all obstacles including natural and environmental. This view was linked with the development of capitalism, the industrial revolution and modern science. As Bacon, one of the founders of modern science put it "The world is made for man, not man for the world". Environmental management and concern amongst most businesses and governments, apart from local problems and wilderness conservation, was at best based on natural resource management. A key example was the ideas of 4 Pinchot in the USA (Dryzeck, 1997) which recognised that humans do need natural resources and that these resources should be managed, rather than rapidly exploited, in order to ensure maximum long-term use.

Sustainable development is a contested concept, with theories shaped by people's and organizations' different worldviews, which in turn influence how issues are formulated and actions proposed. It is usually presented as the intersection between environment, society and economy, which are conceived of as separate although connected entities. We would argue that these are not unified entities: rather they are fractured and multi-layered and can be considered at different spatial levels. The economy is often given priority in policies and the environment is viewed as apart from humans. They are interconnected, with the economy dependent on society and the environment while human existence and society are dependent on, and within the environment. The separation of environment, society and economy often leads to a narrow techno-scientific approach, while issues to do with society that are most likely to challenge the present socio-economic structure are often marginalized, in particular the sustainability of communities and the maintenance of cultural diversity. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment

Objective-To demonstrate the magnitude, timing, and cause of changes in blood pressure that occur in migrants from a low blood pressure population on moving to an urban area.Design-A controlled longitudinal observational study of migrants as soon after migration as possible and follow up at three, six, 12, 18, and 24 months after migration. A cohort of controls living in a rural area who were matched for age, sex, and locality were also observed at the same periods. Viliages on the northern shores of Lake Victoria in western Kenya and Nairobi. Main outcome measures-A medical questionnaire and three 24 hour diet histories were completed by migrants and controls. Height, weight, pulse, and blood pressure were measured. Three 12 hour overnight urine samples were collected from all participants and analysed for sodium, potassium, and creatinine concentrations.Results-The mean systolic blood pressure of migrants was significantly higher than that of controls throughout the study, and the distribution of blood pressure was shifted to the right compared with controls. The mean diastolic blood pressure of the two groups diverged over time. Blood pressure differences were not due to selective migration. The migrants' mean urinary sodium:potassium ratio was higher than that of controls (p<0-001) throughout, and weight and pulse rate were also higher among migrants, although differences diminished with time.

SUMMARY As part of a longitudinal study of migrants who move from a subsistence farming rural society to Nairobi, blood pressures and associated factors were measured in cross sectional studies of members of the Luo tribe in their traditional rural environment and in the urban environment of Nairobi. Blood pressures in Nairobi correlated with duration of urban residence. In the rural area men showed a negligible rise in blood pressure with age, and both sexes showed a significantly smaller rise than in the urban area. Although mean weights of the rural group were smaller, this did not account for all the urban/rural differences in blood pressures. Nevertheless, mean urinary sodium concentration and sodium ratios (sodium/potassium and sodium/creatinine) were significantly higher in the urban group whereas mean urinary potassium concentration and potassium/creatinine ratio were significantly lower. Perhaps the ratio of sodium to potassium in the diet contributes to the different blood pressure profiles of these two populations.Despite several studies of "low blood pressure populations" in Africa,'"7 virtually no data on their sodium intake have been reported. It Both groups of subjects were studied in their homes. A standard questionnaire was administered by trained Luo fieldworkers. Blood pressure was then measured twice using a Hawkesley random zero sphygmomanometer9 after the subject had been lying down for five minutes. Observers had been trained and standardised in blood pressure measurement,'" anddiastolic pressure was recorded at phase 5. Heart rate was recorded between blood pressure readings and the mean of the two blood pressure readings was used for analysis. Weight, height, and triceps skinfold thicknesses were measured using standard techniques." The mean of two skinfold measurements was used for analysis. Finally, a casual urine sample was collected and the time and ambient temperature were recorded. ResultsOf those selected and still resident in the rural area, 98% were studied. All of those traced in Nairobi were included in the urban study. Tables 1 and 2 show that guest. Protected by copyright. on 13 May 2018 by

Studies of ventilatory capacity change in small groups of employees during a shift in a cotton mill and in three cotton ginneries in Uganda, a sisal factory in Kenya, and a jute mill in England, have demonstrated that an effect is produced by the dust in the cotton mill and in a very dusty ginnery but not in two other less dusty ginneries. No significant effect was detected in the sisal factory or in the jute mill despite much higher dust concentrations than in the cotton mill.The dust sampling instruments gave the weight in three sizes: Coarse (>2 mm.), medium (7,u to 2 mm.), and fine (< 7,). The samples were analysed for protein, mineral (ash), and cellulose (by difference). The fine and medium sisal and jute dusts contain less protein than cotton dusts. The physiological changes observed in the employees in the cotton mill indicate the need for general dust measurement and control, even when new carding machinery is installed in a new mill.The ventilatory capacity of normal subjects and of those with byssinosis falls during the course of a day's exposure to the dust in cotton mill card-rooms (McKerrow, McDermott, Gilson, and Schilling, 1958; Bouhuys, Lindell, and Lundin, 1960). The agent producing this effect has not yet been isolated. Davenport and Paton (1962) have shown that cotton dust extracts contain a smooth muscle contractor substance which may be responsible. Antweiler (1960) believes that the agent is a histamine releaser, and Pernis, Vigliani, Cavagna, and Finulli (1961) have suggested that the effect may be due to bacterial endotoxins. Tuffnell (1960) suggests that the substance is in the bracts and pericarp of the cotton boll; this is supported by Nicholls (1962) who has confirmed the presence of a smooth muscle contractor substance in extracts of these parts of the plant and has shown that it caused contraction of isolated human bronchial muscle. Nicholls has also investigated extracts of dust from flax, sisal, and jute mills and found decreasing activity in this order.Here we report complementary studies of the Present addresses: