• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 221
  • 144
  • 17
  • 10
  • 8
  • 8
  • 6
  • 4
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 480
  • 130
  • 103
  • 87
  • 79
  • 49
  • 41
  • 37
  • 37
  • 36
  • 36
  • 35
  • 33
  • 30
  • 29
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Micronutrient dilution associated with alcohol and added sugar intake in the THUSA population / Marita Serfontein.

Serfontein, Marita January 2008 (has links)
The micronutrient intake of the average South African is not optimal. National fortification of staple foods does not solve all micronutrient deficiencies. Furthermore, urbanisation causes a shift in food intake, increasing the availability of cheaper and more energy dense food and drinks that are often lacking in micronutrients. It is unclear whether the current literature provides sufficient evidence of nutrient dilution by the moderate consumption of alcohol and/or added sugar. The aim of the present study was to evaluate the dietary intakes of a population in nutrition transition and determine the effect of intake of alcohol and added sugars on intakes of micronutrients and food groups to provide information for the development of preventive strategies in public health. A number of countries, including South Africa, suggest limited alcohol and sugar intakes in the Food Based Dietary Guidelines but do not quantify this recommendation. Data from the "Transition and Health during Urbanisation in South Africa" survey (THUSA) were analysed for dietary intakes (as determined by a validated quantified food frequency questionnaire), age and body mass index (BMI). The THUSA study was conducted during 1996 and 1998 in the North West Province and included 1854 "apparently healthy". Respondents aged 15 years and older from 37 randomly selected sites from rural and urban areas. Alcohol intake (absolute intake and percentage of energy) was the highest for men living in middle class urban areas. With increased urbanisation, the type of beer shifted from sorghum based to commercial beer. Sixty-one percent of men and 25% of women reported that they consumed alcohol at the time of the survey. Eighteen percent of men and 11.7% of women consumed more than 30g and 15g alcohol per day, respectively (intakes which are regarded as moderate). Men and women consuming the most alcohol had significantly higher mean intakes of most macro and micronutrients. However, the intake of vitamin Bi2, B6, folate, vitamin E and vitamin C did not meet the recommended dietary intake (RDA) across all levels of alcohol intake. Although the total energy intake increased with increased alcohol intake, there was no significant difference between the mean BMI of men or women with different levels of intake. One third of the population consumed more than a 100g of added sugar daily. Intake of sugar was the highest in the farm dwellers but the intake of sweets, cakes, cookies and cold drinks was the highest in the urban areas. As sugar intake increased so did energy, carbohydrates and most micronutrients. However, the intake of vitamin B12, folate, vitamin C and calcium did not meet the RDA across all levels of sugar intake. BMI did not differ between respondents with the highest and lowest sugar intake and no association was found between BMI and sugar intake. The THUSA study was conducted before fortification of staple food became law in October 2003. Maize meal and wheat flour are nowadays fortified with certain vitamins and minerals which may alleviate some micronutrient deficiencies. For future research it is imperative to establish the reasons for low intake of certain micronutrients rather than to look at a single food item in the diets of the South African adult population. Proper education on the intake of cheaper food sources of micronutrients needs to be highlighted at all levels of the health sector. / Thesis (M.Sc. (Dietetics)--North-West University, Potchefstroom Campus, 2009.
122

The Cultural Landscape Engineers: Humans and Environment in the Maroochy District, 1850 – 1950

Berenis Cecile Alcorn Unknown Date (has links)
No description available.
123

La Cité de Besançon de la fin du XIIe au milieu du XIVe siècle étude d'une société urbaine /

Fiétier, Roland. January 1978 (has links)
Thesis--Université de Nancy II, 1976. / Includes bibliographical references (p. xvi-li) and index.
124

"Vår marknad i Skåne" : bebyggelse, Handel och urbanisering i Skänor och Falsterbo under medeltiden /

Ersgård, Lars. January 1988 (has links)
Akademisk avhandling--Humanistiska Fakulteten--Lund, 1988. / Résumé en anglais.
125

Organisation de l'espace urbain et problèmes d'aménagement dans la région de Gagnoa

Yohore, Gobredi, January 1988 (has links)
Th. 3e cycle--Géogr. de l'aménage.--Clermont-Ferrand 2, 1988.
126

Dynamiques périurbaines à l'épreuve de la décentralisation : l'expérience de la commune de Kalabancoro au Mali / Periurban dynamics to the test of decentralization : the example of the municipality of Kalabancoro in Mali

Kouma, Mamadou 09 March 2017 (has links)
Cette thèse s’inscrit dans le cadre des interrogations sur les mutations et les recompositions des villes africaines, confrontées à l’urbanisation de leurs périphéries au moment de la mise en œuvre des politiques de décentralisation. Symbole des conflits d’appropriation foncière et des recompositions territoriales qui secouent les communes mitoyennes de Bamako, la commune de Kalabancoro a été notre terrain de recherche sur la base de caractéristiques spécifiques : pressions démographique et foncière, fragmentation du territoire de la commune et les problèmes de gestion qui en découlent, présence d’une cohorte d’acteurs, conditions fiscales moins contraignantes qui favorisent l’installation de nouveaux commerces.Par ailleurs, les investissements privés et publics y sont importants. En partenariat avec des promoteurs privés, l’État entend résorber ses besoins fonciers sur le territoire de Kalabancoro à travers la construction de logements sociaux et d’autres édifices publics. Ces projets obéissent à des orientations politiques dont l’exécution est rendue difficile par la multiplicité des intérêts en jeu. Outre ces difficultés, les services de l’État doivent arbitrer des conflits entre les acteurs impliqués dans la gestion du territoire et de ses fragmentsEn somme, il s’agit dans ce travail de questionner les modalités de formation des périmètres communaux, en mettant en débat la décentralisation, ses contours et ses effets sur l’urbanisation de la périphérie bamakoise ; mais aussi d’identifier les acteurs situés à différentes échelles territoriales, analyser leurs rôles dans la transformation du territoire à travers leurs relations et interrelations. / I propose to question the modalities of establishment of communal territories, by debating decentralization, its contours and its effects on the urbanization of Bamako's periphery; but also to identify the actors located at different territorial scales, to analyze their roles in the transformation of the territory according their relations and interrelations.
127

Assessing the effects of urban development and climate change on flooding in the Greater Port-Harcourt watershed, Niger Delta, Nigeria

Dan-Jumbo, Nimi Gibson January 2018 (has links)
Developing countries have been rapidly urbanising over the last decades, resulting in major environmental pressures and increased vulnerability to natural disasters. A complex combination of factors, including climate change, land use change, poorly implemented regulation and a lack of integrated planning has often resulted in environmental degradation and disproportionate impacts of natural disasters affecting millions worldwide, particularly in tropical cities. The main aim of this study is to understand the effects of land-use and climate change on flooding in the Greater Port-Harcourt watershed. The specific research objectives were: to understand the historical and future land use /land cover changes; to understand the magnitude of change in hydrologic and hydraulic conditions due to land-use and climate changes; to assess the influence of different forest mitigation scenarios on peak-discharge; and to make recommendations on how to improve future planning using insights from this study. Methodologically, the post-classification change detection method was applied to examine the extent and nature of historical LULC changes using remotely sensed data. Future LULC changes were estimated by superimposing the 2060 digitised Masterplan map on the year 2003 baseline imagery. Hydrologic changes were assessed using HEC-HMS model, while changes in the hydraulic condition were assessed using HEC-RAS model. Model output was further used to map flood hazards, flood zones and damage potential. Priority areas and infrastructure at risk were identified by means of their location in flood zones and exposure to floods with high damage potential. On the extent of change, this study revealed that urbanisation and loss of agricultural land had been the dominant and intensive land use change in the watershed. Urbanisation is projected to almost double its 2003 extent by 2060 and is likely to remain the dominant force of land use change. On the nature of change, this study found that urban land was the most dynamic in terms of gross gain and net change. It exhibited the grossest gain (about 9% of the watershed) and the grossest loss leading to a high net change of about 8.6%. In fact, the most prominent transition was the conversion of agricultural land (about 422km2) to urban land, and roughly 93.3% of all conversions to urban land resulted from agricultural land. On the process of change, urban land mainly experienced a net-type of change (change in quantity), whereas changes in agricultural land was more of a swap-type of change (change in location). Importantly, the study reveals that the impact on flood flow was historically significant (about 68%) and is projected to amplify in future, however, these changes are largely attributed to increased storm size. Urbanisation is likely to have little or no impact on annual maximum peak flow at the watershed scale; however, urbanisation is projected to have a considerable impact on peak flow in a number of subbasins, which could have severe implications for flash flooding in those subbasins. Similarly, afforestation could have little or no impact on future maximum peak flow when assessed at the watershed scale. Although some subbasins experienced changes in peak flow, the effect of forest is variable. The study concludes that although the impact of urbanisation is projected to be insignificant at the watershed scale, it could also increase flood risk due to increasing developments in floodplains and channel encroachment. Priority infrastructure and areas requiring urgent flood risk management include the Port-Harcourt seaports, Onne seaport, the University of Science and Technology and cement factory. Priority areas in the Masterplan are mainly in the south (Phase 3), comprising of the Air force base and the residential area near Onne seaport. Lastly, approximately 8.1km and 189m of road and rail network are at greater risk of flooding by means of their exposure to floods with the highest damage potential. Based on this study, I have furthered understanding by showing that the transition to urban land category was dominated by net changes (i.e. changes in quantity). I have also furthered understanding by showing that substantial changes in future urban land-use may not have significant effect on flood parameters. My main contribution to knowledge is that despite the high rate of urbanisation in the GPH watershed and its minimal impact on flooding (which could be due the large size of the storm and watershed), urbanisation could still increase flood risk due to greater exposure of elements at risk in the flood plains to damaging floods. Based on the results, the study recommends that the development authorities should integrate both structural measures (mainly for flood defence around existing developments) and non-structural measures (primarily for future developments). For flood risk management research, this study recommends that conclusions about the effects of urbanisation should not be made solely on the basis of changes in hydrology and river hydraulics, however researchers should also consider the exposure of important elements at risk within the floodplains under study to better understand the effects of urbanisation. Moreover, to better understand urbanisation effects on runoff dynamics in other watersheds, this study recommends that research efforts should be concerted in understanding subbasin-scale changes given that the effects of urbanisation are more pronounced in smaller basins.
128

Urbanisation and Shifting Phenotypes Behavioural, Physiological and Cognitive Strategies of the Indian Rock Agama Psammophilus Dorsalis

Batabyal, Anuradha January 2017 (has links) (PDF)
Humans directly or indirectly cause changes in the environment, and urbanisation is currently one of the most important threats to biodiversity. Urbanisation exposes organisms to novel pressures that are drastically different from those in their native habitats, as human modification rapidly and dramatically changes natural environments, alters habitats as well as shifts resources and predator communities. Organisms can cope with the novel challenges by modifying their behaviour, physiology, morphology and cognition. To understand the impacts of urbanisation on phenotypic traits, the goal of my research was to study the social and survival strategies of the Indian rock agama, Psammophilus dorsalis. Using a combination of field and laboratory-based experiments, I examined differences in signal-receiver dynamics in communication, anti-predator strategies, stress physiology, and spatial learning. Social interactions in this species involve rapid physiological colour changes and behavioural displays. My work shows that colour patterns are diametrically different between courtship and aggressive interactions. Males change their dorsal body region to red, and their lateral body region to black when courting females, whereas these regions turn yellow and orange respectively when fighting with competitive males. Regardless of social context, suburban males express lower colour contrast and are also slower to change colours than rural males. Using robotic lizard stimuli, I found that receiver responses match the population-specific intensity of male signals. For the first time in any lizard species, I find that perception and responsiveness to motion and colour are lateralized in different ways. Psammophilus dorsalis is left visual field dominant when responding to social display colours, but motion stimuli elicit similar responses from both visual field. Along with shifts in colour signalling strategies, stress physiology and social behavioural display was also affected by urbanisation. Suburban males had significantly higher circulating corticosterone levels during both control conditions and immediately following social interactions compared to rural males. Proportion and rate of courtship displays was also significantly lower in suburban males compared to rural males. In the field, escape strategies of males, but not females differed between suburban and rural populations, such that suburban males were more tolerant of simulated predator attacks than rural males. As expected from their cryptic body patterns, females, regardless of habitat, relied more heavily on crypticity rather than flight to minimize predation risk. Suburban males also had stronger cognitive skills, as spatial learning and reversal learning in suburban males was faster than in rural males. In sum, differences in these behavioural, physiological, and cognitive responses of suburban and rural populations of lizards demonstrated in my thesis, indicate human-induced changes in selective pressures that support shifted survival and reproductive strategies. Psammophilus dorsalis promises to be an excellent system to further examine the specific selective pressures that shift in urban landscapes. The study of multiple integrated phenotypic traits in response to urbanisation gives a broader perspective as to how a species can flexibly adapt to rapid environmental disturbances, which is currently one of the greatest threats to biodiversity worldwide.
129

The Economic consequenses of urbanisation in Lebowa

Koornhof, Gerhardus Willem January 1982 (has links)
The problem identified in this study is that of a rapidly growing urbanisation process in the world in general and in Africa in particular. The national states in South Africa will not escape this process. The purpose of this study was to contribute to a better understanding of this phenomenon as it is developing in one of the national states, namely Lebowa. To achieve this, a thorough description of the extent of urbanisation, internationally and within the study area, as well as of the underlying causes of urbanisation, was necessary. Urbanisation can only be understood in its historical context. During the past century, Africa has experienced a low level but an increasing rate of urbanisation. A high urban population growth rate is projected for Lebowa in the next four decades. This will place a tremendous pressure on the resources of the country and on the planning capability of the Government. The development of urban places in Lebowa focuses on the simultaneous stimulation of many smaller places, distributing capital, manpower and services among the eighteen proclaimed townships. Some of these towns lack an economic basis and were, instead, created incidental to ideological motives. The provision of the social and physical infrastructure in Lebowa is at present largely founded on the guidelines for urban development, which has particular economic co sequences for urbanisation. This research makes two main contributions to the study of urbanisation in the national states in general and in Lebowa in particular. Firstly, a new classification regarding the definition of urbanisation in Lebowa is proposed which is a more realistic approach in an Africa context. It mainly distinguishes between the urban and semi-urban population on the one hand and the rural population on the other hand, paying particular attention to the identification of the semi-urban population. This classification indicates that the process of urbanisation in Lebowa has already reached an advanced stage and that it can be expected that this process will accelerate towards the end of the century. Secondly, it is argued that the present policy of developing many smaller urban places should be replaced by a co-ordinated urbanisation strategy, concentrating on the development of a few selected larger towns. Such a policy would provide lebowa with a framework for the development of an urban structure which will be capable of absorbing the projected urban explosion. The implementation of a policy directed at the promotion of healthy urban development in Lebowa will need political commitment and adoption of a population programme to bring the existing high population growth rate into line with the economic capacity of the country. Urbanisation should not only be promoted in lebowa but also in the whole Northern Transvaal region. because of the interdependence of different areas in the region. This will require the development of an urbanisation strategy which will have to be linked to a national urbanisation strategy for South Africa. / Thesis (DCom)--University of Pretoria, 1982. / gm2014 / Economics / unrestricted
130

Les effets maternels en tant que médiateurs des changements globaux : mécanismes et conséquences sur les populations d'oiseaux : comparaison de populations à différents niveaux d'urbanisation / Maternal effects as mediators for climate change : mechanisms and consequences on birds populations

Vaugoyeau, Marie 05 March 2015 (has links)
Dans le contexte des changements globaux, la transformation du milieu rural ou naturel en milieu urbain est particulièrement bien étudiée. A la fois cause et conséquences des changements, l’urbanisation exerce de fortes pressions de sélection sur les populations et les écosystèmes. En effet, les facteurs tels que la perte d’habitat naturel, la hausse de la température, de la luminosité ou de la perméabilité des sols érodent la biodiversité en ville. Les contraintes environnementales influencent les phénotypes et la survie des organismes. Les parents peuvent moduler l’influence de l’environnement sur le phénotype du jeune et du futur adulte en s’investissant dans la reproduction. L’objectif de cette thèse était de comprendre le rôle des effets maternels sur les phénotypes des oiseaux urbains à travers la description et la mise en relation des variations environnementales, phénologiques et phénotypiques entre et au sein de populations aviaires à différents niveaux d’urbanisation. Pour mener à bien ce projet, deux espèces ont été sélectionnées : les mésanges bleues (Cyanistes caeruleus) et les mésanges charbonnières (Parus major) présentes le long du gradient urbain-rural. Le suivi de trois saisons de reproduction a été réalisé sur sept sites en zone urbanisée (parcs et jardins de Paris), une saison sur trois sites en zone semi-urbanisée et cinq saison sur deux sites en zone rurale (forêt de Fontainebleau et bois privés du CEREEP). La phénologie, le succès de reproduction ainsi que le phénotype (condition corporelle, condition physiologique et signaux colorés) des adultes et des jeunes ont été mesurés. Les résultats montrent que l’urbanisation n’influence pas la phénologie mais le succès de reproduction des deux espèces est plus faible sur Paris par rapport à la zone rurale. De plus, la coloration des adultes et la condition corporelle des jeunes varient avec l’habitat. Afin de mieux comprendre ce qui influence la coloration des mésanges charbonnières, une expérience de supplémentation a été mise en place après la mue des adultes. Enfin pour mieux cibler l’effet de la température sur le succès de reproduction des mésanges charbonnières, une expérience de chauffage des nids a été réalisée. Tous les résultats récoltés montrent que les mésanges bleues et charbonnières ont de grandes capacités d’adaptation aux facteurs environnementaux même si leur succès de reproduction est diminué en zone urbaine ce qui explique en partie la pérennité de leurs présences dans les centres urbains à travers l’Europe. / In global changes context, the transformation of rural or natural area into urban area is well studied. At once cause and consequence of global changes, urbanization induces high selections pressures on populations and ecosystems. Factors such as habitat destruction, temperature, luminosity and soil permeability increase diminish biodiversity in town. Environmental characteristics influence phenotypes and survival of organisms. Parents can modulate environmental influence on young or future adult phenotype by investing in reproduction. The aim of this thesis was to understand the role of maternal effects on urban bird phenotypes through description and relation between environmental variation, differences in phenology and in phenotypes within and among populations at different levels of urbanization. For this purpose, two species were selected; the blue tit (Cyanistes caeruleus) and the great tit (Parus major), present along an urbanisation gradient. Monitoring of three reproductive seasons were realised in seven sites in urban area, (parks of Paris), on in three sites in suburban areas and five reproductive seasons in two sites in rural area (Fontainebleau forest and private forest of CEREEP). The phenology, reproductive success and phenotype (coloured signals, body and physiological condition) of adults and nestlings were measured. Thesis results showed that for the two species, phenology did not differ between habitats but reproductive success was lower in Paris than in rural areas. Moreover, great tit coloration and nestling body condition varied with habitat. In order to understand how and which factors influenced great tit colouration, a supplementation experiment was realised after moult. Finally to study temperature influence on great tit reproductive success, a heating nest experiment was realised. Thesis results showed that blue and great tits are highly able to adapt to urban environments even if their reproductive success was decreased in urban area which explained presence in all Europeans cities.

Page generated in 0.0819 seconds