Scientism and instrumentalism After the Bomb: Dr Strangelove, End Zone, Crash and The Wire

This thesis argues that through the prism of America’s Cold War, scientism has emerged as the metanarrative of the postnuclear age. The advent of the bomb brought about a new primacy for mechanical and hyperrational thinking in the corridors of power not just in terms of managing the bomb itself but diffusing this ideology throughout the culture in social sciences, economics and other such institutional systems. The human need to mitigate or ameliorate against the chaos of the universe lies at the heart of not just religious faith but in the desire for perfect control. Thus there has been a transference of power from religious faith to the apparent material power of science and technology and the terra firma these supposedly objective means supply. The Cold War, however was a highly ideologically charged opposition between the two superpowers, and the scientific methodology that sprang forth to manage the Cold War and the bomb, in the United States, was not an objective scientific system divorced from the paranoia and dogma but a system that assumed a radically fundamentalist idea of capitalism. This is apparent in the widespread diffusion of game theory throughout Western postindustrial institutions. The inquiry of the thesis thus examines the texts that engage and criticise American Cold War methodology, beginning with the nuclear moment, so to speak, and Dr Strangelove’s incisive satire of moral abdication to machine processes. Moving on chronologically, the thesis examines the diffusion of particular kinds of masculinity and sexuality in postnuclear culture in Crash and End Zone and finishing up its analysis with the ethnographic portrayal of a modern American city in The Wire. More than anything else, the thesis wishes to reveal to what extent this technocratic consciousness puts pressure on language and on binding narratives.

The relationship between rural livelihoods and livestock keeping: the case of Sidama Zone, Southern Ethiopia

This study examines the relationship between rural livelihoods and livestock keeping in Sidama Zones, southern Ethiopia. The livelihood context, assets and strategies of households are the key features of rural livelihoods considered in the study; while households’ livestock ownership, dependence on livestock and livestock management are the main aspects of livestock keeping examined. The study used the sustainable livelihood approach as a framework for data collection and analysis. Describing the main features of rural livelihoods and livestock keeping, and the general pattern of relationship between them, this study mainly aims at identifying the main livelihood factors that determine livestock keeping in the study area. Descriptive statistics, pair wise correlations, mean comparisons and analysis of variance were used to describe rural livelihoods and livestock keeping as well as the relationship between them. Tobit regressions were used to examine the effect of the various livelihood factors on households’ livestock ownership and dependence; Poisson regressions are used to investigate the factors that influence the intensity of livestock management measured by the use of different technologies and inputs. The findings indicated that a number of livelihood factors - assets, livelihood strategies, livelihood shocks and institutional supports - significantly determine the different aspects of livestock keeping. These include: human assets such as age, education and family size; social assets such as membership to social groups; financial assets such as credit; natural assets such as land, and household physical assets; and livelihood strategies such as diversification into farm and nonfarm activities, and coping mechanisms. In addition the livelihood vulnerability context such as shocks and institutional support are among the main determinants of livestock keeping. The results, by and large, matched the findings of previous studies, and it is concluded that households livestock keeping depends on their livelihoods. Accordingly, it is recommended that policies aiming at livestock asset building and productivity improvement should take the livelihoods of rural households in to consideration. As such the study contribute to scholarly works in the area of rural livelihoods, in general, and livestock keeping, in particular. It also contributes to a better understanding of the problems of livestock keeping within the context of rural livelihoods in the country and to the formulation of appropriate policy for the development of the sector.

Physical controls on the seasonal migration of the North Pacific transition zone chlorophyll front

The large seasonal migration of the transition zone chlorophyll front (TZCF) is of interest because a number of marine fauna, both commercial and endangered, appear to track it. Herein we examine the physical dynamics driving this seasonal migration of the TZCF. Vertical processes, traditionally viewed as controlling the dynamical supply of nutrients to surface waters, prove insufficient to explain seasonal variations in nutrient supply to the transition zone. Instead, we find that the horizontal Ekman transport of nutrients from higher latitudes drives the TZCF's southward migration. The estimated horizontal transport of nitrate supports up to 40% of new primary productivity in the region annually and nearly all of new primary productivity in the winter. The significance of horizontal advection to the North Pacific transition zone supports revising the paradigm that nutrients are supplied to surface waters from below. © 2010 by the American Geophysical Union.

Interactions spatiales et auto-organisation des végétations semi-arides

Les recherches récapitulées dans cette thèse de doctorat ont porté sur les causes de l’organisation spatiale des végétations périodiques. Ces structures paysagères aux motifs réguliers, tachetés, tigrés ou labyrinthiques, d’échelle décamétrique à hectométrique, couvrant des étendues considérables sur au moins trois continents, constituent un cas d’école dans l’étude des processus endogènes présidant à l’hétérogénéité du couvert végétal. Ces structures prennent place sur un substrat homogène, mis à part la rétroaction du couvert lui-même, et sont marquées par des écotones abrupts et la persistance d’une proportion considérable de sol nu. Plusieurs modèles ont mis en avant l’existence possible d’un phénomène d’auto-organisation du couvert, qui verrait une structure d’ensemble émerger des interactions locales entre individus. Ces modèles se basent sur le jeu simultané de la consommation de la ressource (compétition) et de l’amélioration de l’un ou l’autre des éléments du bilan de la même ressource par le couvert (facilitation). La condition à l’existence d’une structure d’ensemble spatialement périodique et stable réside dans une différence entre la portée de la compétition (plus grande) et celle de la facilitation. L’apparition de ces structures est modulée par le taux de croissance biologique, qui est le reflet des contraintes extérieures telles que l’aridité, le pâturage ou la coupe de bois. Le modus operandi des interactions spatiales supposées entre individus reste largement à préciser.

Nos recherches ont été menées au sud-ouest de la République du Niger, à l’intérieur et dans les environs du parc Régional du W. Trois axes ont été explorés :(i) Une étude de la dépendance spatiale entre la structure de la végétation (biovolumes cartographiés) et les paramètres du milieu abiotique (relief, sol), sur base d’analyses spectrales et cross-spectrales par transformée de Fourier (1D et 2D). (ii) Une étude diachronique (1956, 1975 et 1996) à large échelle (3000 km²) de l’influence de l’aridité et des pressions d’origine anthropique sur l’auto-organisation des végétations périodiques, basée sur la caractérisation de la structure spatiale des paysages sur photos aériennes via la transformée de Fourier en 2D. (iii) Trois études portant sur les interactions spatiales entre individus :En premier lieu, via l’excavation des systèmes racinaires (air pulsé) ;Ensuite, par un suivi spatio-temporel du bilan hydrique du sol (blocs de gypse) ;Enfin, via le marquage de la ressource par du deutérium.

Nous avons ainsi pu établir que les végétations périodiques constituent bien un mode d’auto-organisation pouvant survenir sur substrat homogène et modulé par les contraintes climatiques et anthropiques. Un ajustement rapide entre l’organisation des végétations périodiques et le climat a pu être montrée en zone protégée. La superficie et l’organisation des végétations périodiques y ont tour à tour progressé et régressé en fonction d’épisodes secs ou humides. Par contre, en dehors de l’aire protégée, la possibilité d’une restauration du couvert semble fortement liée au taux d’exploitation des ressources végétales. Ces résultats ont d’importantes implications quant à la compréhension des interactions entre climat et écosystèmes et à l’évaluation de leurs capacités de charge. La caractérisation de la structure spatiale des végétations arides, notamment par la transformée de Fourier d’images HR, devrait être généralisée comme outil de monitoring de l’état de ces écosystèmes. Nos études portant sur les modes d’interactions spatiales ont permis de confirmer l’existence d’une facilitation à courte portée du couvert végétal sur la ressource. Cependant, cette facilitation ne semble pas s’exercer sur le terme du bilan hydrique traditionnellement avancé, à savoir l’infiltration, mais plutôt sur le taux d’évaporation (deux fois moindre à l’ombre des canopées). Ce mécanisme exclut l’existence de transferts diffusifs souterrains entre sols nu et fourrés. Des transferts inverses semblent d’ailleurs montrés par le marquage isotopique. L’étude du bilan hydrique et la cartographie du micro-relief, ainsi que la profondeur fortement réduite de la zone d’exploitation racinaire, jettent de sérieux doutes quant au rôle communément admis des transferts d’eau par ruissellement/diffusion de surface en tant que processus clé dans la compétition à distance entre les plantes. L’alternative réside dans l’existence d’une compétition racinaire de portée supérieure aux canopées. Cette hypothèse trouve une confirmation tant par les rhizosphères excavées, superficielles et étendues, que dans le marquage isotopique, montrant des contaminations d’arbustes situés à plus de 15 m de la zone d’apport. De même, l’étude du bilan hydrique met en évidence les influences simultanées et contradictoires (facilitation/compétition) des ligneux sur l’évapotranspiration.

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This PhD thesis gathers results of a research dealing with the causes of the spatial organisation of periodic vegetations. These landscape structures, featuring regular spotted, labyrinthine or banded patterns of decametric to hectometric scale, and extending over considerable areas on at least three continents, constitute a perfect study case to approach endogenous processes leading to vegetation heterogeneities. These patterns occur over homogeneous substratum, except for vegetation’s own feedbacks, and are marked by sharp ecotones and the persistence of a considerable amount of bare soil. A number of models suggested a possible case of self-organized patterning, in which the general structure would emerge from local interactions between individuals. Those models rest on the interplay of competitive and facilitative effects, relating to soil water consumption and to soil water budget enhancement by vegetation. A general necessary condition for pattern formation to occur is that negative interactions (competition) have a larger range than positive interactions (facilitation). Moreover, all models agree with the idea that patterning occurs when vegetation growth decreases, for instance as a result of reduced water availability, domestic grazing or wood cutting, therefore viewing patterns as a self-organised response to environmental constraints. However the modus operandi of the spatial interactions between individual plants remains largely to be specified.

We carried out a field research in South-West Niger, within and around the W Regional Park. Three research lines were explored: (i) The study of the spatial dependency between the vegetation pattern (mapped biovolumes) and the factors of the abiotic environment (soil, relief), on the basis of spectral and cross-spectral analyses with Fourier transform (1D and 2D). (ii) A broad scale diachronic study (1956, 1975, 1996) of the influence of aridity and human induced pressures on the vegetation self-patterning, based on the characterisation of patterns on high resolution remote sensing data via 2D Fourier transform. (iii) Three different approaches of the spatial interactions between individuals: via root systems excavation with pulsed air; via the monitoring in space and time of the soil water budget (gypsum blocks method); and via water resource labelling with deuterated water.

We could establish that periodic vegetations are indeed the result of a self-organisation process, occurring in homogeneous substratum conditions and modulated by climate and human constraints. A rapid adjustment between vegetation patterning and climate could be observed in protected zones. The area and patterning of the periodic vegetations successively progressed and regressed, following drier or wetter climate conditions. On the other hand, outside protected areas, the restoration ability of vegetation appeared to depend on the degree of vegetation resource exploitation. These results have important implications regarding the study of vegetation-climate interactions and the evaluation of ecosystems’ carrying capacities. Spatial pattern characterisation in arid vegetations using Fourier transform of HR remote sensing data should be generalised for the monitoring of those ecosystems. Our studies dealing with spatial interaction mechanisms confirmed the existence of a short range facilitation of the cover on water resource. However, this facilitation does not seem to act through the commonly accepted infiltration component, but rather on the evaporative rate (twice less within thickets). This mechanism excludes underground diffusive transfers between bare ground and vegetation. Inverse transfers were even shown by deuterium labelling. Water budget study and micro-elevation mapping, along with consistent soil shallowness, together cast serious doubts on the traditional mechanism of run-off/diffusion of surface water as a key process of the long range competition between plants. An alternative explanation lies in long range root competition. This hypothesis find support as well in the excavated root systems, shallow and wide, as in isotopic labelling, showing contaminations of shrubs located up to 15 m of the irrigated area. Water budget study also evidenced simultaneous contradictory effects (facilitation/competition) of shrubs on evapotranspiration.

Deforestation and the spatio-temporal distribution of savannah and forest members of the Simulium damnosum complex in southern Ghana and south-western Togo

Spatio-temporal data on cytotaxonomic identifications of larvae of different members of the Simulium damnosum complex collected from rivers in southern Ghana and south-western Togo from 1975 until 1997 were analysed. When the data were combined, the percentages of savannah blackflies (S. damnosum sensu stricto and S. sirbanum) in the samples were shown to have been progressively increasing since 1975. The increases were statistically significant (P < 0·001), but the rates of increase were not linear. Further analyses were conducted according to the collection seasons and locations of the samples, to account for possible biases such as savannah flies occurring further south in the dry season or a preponderance of later samples from northern rivers having more savannah flies. These analyses showed that the increasing trend was statistically significant (P< 0·0001) only during the periods April to June and October to December. The presence of adult savannah flies carrying infective larvae (L3) indistinguishable from those of Onchocerca volvulus in the study zone was confirmed by examinations of captured flies. The percentages of savannah flies amongst the human-biting populations and the percentages with L3s in the head were higher during dry seasons than wet seasons and the savannah species were found furthest south (5 °25′N) in the dry season. Comparisons of satellite images taken in 1973 and 1990 over a study area in south-western Ghana encompassing stretches of the Tano and Bia rivers demonstrated that there have been substantial increases in urban and savannah areas, at the expense of forest. This was so not only for the whole images but also for subsamples of the images taken at 1, 2, 4, 8 and 16 km distant from sites alongside the River Tano. At every distance from the river, the percentages of pixels classified as urban or savannah have increased in 1990 compared with 1973, while those classified as degraded or dense forest have decreased. The possibility that the proportionate increases in savannah forms of the vectors of onchocerciasis, and hence in the likelihood of the transmission of savannah strains of the disease in formerly forested areas, were related to the decreases in forest cover is discussed.

CFD analysis of one-dimensional infiltration in vadose zone

This study presents a CFD analysis constructed around PHYSICA, an open framework for multi-physics computational continuum mechanics modelling, to investigate the water movement in unsaturated porous media. The modelling environment is based on a cell-centred finite-volume discretisation technique. A number of test cases are performed in order to validate the correct implementation of Richard's equation for compressible and incompressible fluids. The pressure head form of the equation is used together with the constitutive relationships between pressure, volumetric water content and hydraulic conductivity described by Haverkamp and Van Genuchten models. The flow problems presented are associated with infiltration into initially dry soils with homogeneous or layered geologic settings. Comparison of results with the problems selected from literature shows a good agreement and validates the approach and the implementation.

Zone based systems design framework for the realisation of efficient block cipher based message authentication code algorithms

A zone based systems design framework is described and utilised in the implementation of a message authentication code (MAC) algorithm based on symmetric key block ciphers. The resulting block cipher based MAC algorithm may be used to provide assurance of the authenticity and, hence, the integrity of binary data. Using software simulation to benchmark against the de facto cipher block chaining MAC (CBC-MAC) variant used in the TinySec security protocol for wireless sensor networks and the NIST cipher block chaining MAC standard, CMAC; we show that our zone based systems design framework can lead to block cipher based MAC constructs that point to improvements in message processing efficiency, processing throughput and processing latency.