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Making place at the end of the world : an ethnography of tourism and urban development in Ushuaia, Argentina’s Antarctic Gateway City.Herbert, Andrea January 2014 (has links)
This thesis is concerned with the lived experience of placemaking in Argentina’s Antarctic gateway port Ushuaia. Based on 12 months ethnographic fieldwork, it explores the relations between tourism, urban development, and socio-economic difference. As such, it investigates how agents from across the social spectrum conceive of, and construct their sense of place “at the end of the world”. As the world’s southernmost city, Ushuaia is attractive to tourists for its stunning landscapes, unique location, and strategic proximity to Antarctica. However, the image of a friendly tourist destination crucial to everyday life in this Patagonian city is contested by its stakeholders. This thesis looks beyond the image presented to tourists to explore frictions among residents, the city council, and touristic enterprises.
Ushuaia is revealed as an urban location beset by growing unrest due to issues of population growth and social polarization. This is analyzed in relation to its geopolitical significance for the Argentine state, territorial struggles with Chile, and economic incentives for in-migration. Consequently, this thesis considers the dynamic and shifting character of the city’s population through an engagement with economic and lifestyle migrants, including those dwelling in non-legal settlements, and tourists who occupy Ushuaian space alongside more longstanding citizens. The thesis demonstrates how conflicting views collide regarding issues of urbanization, industrialization, tourism, and environmental conservation, analyzed in relation to the interests and concerns of different social constituencies. Through extensive interviewing with a diverse array of social actors, this thesis also explores the different levels of economic and socio-cultural attachment to Antarctica, suggesting a schism between Ushuaia’s touristic representation, Antarctic alignment, and the needs and interests of its inhabitants. This thesis, then, explains the diverging place-based ideas and aspirations of different social groups in relation to the governmental, socio-economic, and socio-cultural forces implicated in placemaking.
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Elementos-traço (mercúrio total, selênio e cobre) em penas de pinguins do gênero Pygoscelis da Ilha Rei George, Antártica / Trace elements (total mercury, selenium and cooper) in feathers of penguins Pygoscelis of King George Island, AntarcticaNatalia Beloto 28 May 2013 (has links)
Este estudo teve como objetivo avaliar a magnitude da exposição de pinguins do gênero Pygoscelis da Antártica ao mercúrio total (HgT), selênio (Se) e cobre (Cu) e verificar a variabilidade destes elementos-traço de acordo com suas características biológicas, para tal foram utilizadas penas do peito de Pygoscelis papua (n=30), P. antarctica (n=21) e P. adeliae (n=48) que corresponderam àquelas coletadas em animais da Ilha Rei George, Antártica. Encontrou-se níveis aparentemente inferiores de HgT e Se em P. papua tendo também sido a espécie que mais se distinguiu das outras duas. Além disto, houve correlação entre os níveis de HgT e Se para as espécies P. antarctica e P. adeliae indicando que é possível que ocorra nos pinguins um processo de destoxificação do mercúrio orgânico por meio do selênio, porém isto não pôde foi confirmado. Ressalta-se que o atual estudo é o primeiro a relatar níveis de HgT em penas do peito da espécie P. antarctica, sendo esta informação relevante para o entendimento e conservação desta espécie de pinguim da Antártica. De modo geral o cobre (8346/32545 ng/g p.s. mín/máx) foi o elemento que apareceu em concentrações maiores se comparado ao selênio (618,7/7923,5 ng/g p.s. mín/máx) e mercúrio total (114,6/1180,2 ng/g p.s. mín/máx). Estas elevadas concentrações de cobre nas penas possivelmente se deve a incorporação via alimentação composta essencialmente de krill, que é um crustáceo de altas concentrações deste elemento essencial. Genericamente foi possível observar que todas as informações reportadas no atual trabalho, tais como as correlações entre os elementos-traço (HgT e Se) e características biológicas, mostram que as três espécies de pinguins analisadas seguem padrões distintos de distribuição de elementos-traço possivelmente porque apresentam dieta diferenciada, além disto, é provável que as características individuais influenciem nestes padrões, e por isto devem ser avaliadas para um melhor entendimento da distribuição dos elementos-traço nestes animais. Observa-se que as concentrações do elemento-traço não essencial HgT aparentemente não constituiu uma ameaça aos pinguins porque foi inferior ao nível considerado prejudicial a aves, enquanto o selênio é um elemento que deve ser constantemente monitorado pois exibiu concentrações próximas àquelas considerada danosa para aves quando incorporadas via dieta. Verificou-se que a presença dos elementos-traço não constitui uma ameaça a saúde dos Pygoscelis da Ilha Rei George, apesar disso, faz-se necessária a realização de um programa de monitoramento constante nesta região, que é uma área ainda considerada como não impactada pela ação antrópica. / This study assessed the magnitude of Antarctic penguins, genus Pygoscelis, exposure to trace elements as total mercury (THg), selenium (Se) and copper (Cu) to check some variations of these elements according to biological characteristics of the animals. To conduct this, breast feathers of Pygoscelis papua (n = 30), P. antarctica (n = 21) and P. adeliae (n = 48) were taken and analysed from seabirds collected from King George Island, Antarctica. Apparently was found lower levels of THg and Se in P. papua than in others penguins species, and this one specie also corresponded to the greater different trace element level found in Pygoscelis penguins. It was found correlation between THg and Se levels for P. antarctica and P. adeliae indicating that it is possible that the penguins can have detoxification process of the organic mercury by selenium, but this could not be confirmed. It is noteworthy that present study is the first to report THg levels in breast feathers of the species P. antarctica, being this information relevant for the understanding and conservation of this species of penguin in Antarctica. Overall, copper (8346/32545 ng / g d.w. min / max) was the element that appeared in higher concentrations compared to selenium (618.7 / 7923.5 ng / g d.w. min / max) and total mercury (114 , 6/1180, 2 ng / g d.w. min / max). These high concentrations of copper in feathers is possibly caused by incorporation through food items of the penguins, that consists mainly of krill. This crustacean also have high concentrations of this essential element. It was observed that all the information reported in this study, such as correlations between trace elements (THg and Se) and biological characteristics, show that the three penguin species follow different patterns of distribution of trace elements, and it is perhaps because they have diet differentiated. Moreover, it seems that the individual characteristics also influence these patterns, and therefore should be evaluated for a better understanding of the distribution of trace elements in these animals. It was observed that the concentrations of non-essential trace element THg apparently not constitute a threat to penguins because it was below the level considered harmful, while selenium is an element that must be constantly monitored because exhibited concentrations close to those considered potentially harmful to birds when incorporated via diet. It was found that the presence of trace elements does not constitute a threat to the health of Pygoscelis from King George Island. Nevertheless, a constant monitoring program is necessary for the region, which is still considered a preserved environment.
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Elementos-traço (mercúrio total, selênio e cobre) em penas de pinguins do gênero Pygoscelis da Ilha Rei George, Antártica / Trace elements (total mercury, selenium and cooper) in feathers of penguins Pygoscelis of King George Island, AntarcticaNatalia Beloto 28 May 2013 (has links)
Este estudo teve como objetivo avaliar a magnitude da exposição de pinguins do gênero Pygoscelis da Antártica ao mercúrio total (HgT), selênio (Se) e cobre (Cu) e verificar a variabilidade destes elementos-traço de acordo com suas características biológicas, para tal foram utilizadas penas do peito de Pygoscelis papua (n=30), P. antarctica (n=21) e P. adeliae (n=48) que corresponderam àquelas coletadas em animais da Ilha Rei George, Antártica. Encontrou-se níveis aparentemente inferiores de HgT e Se em P. papua tendo também sido a espécie que mais se distinguiu das outras duas. Além disto, houve correlação entre os níveis de HgT e Se para as espécies P. antarctica e P. adeliae indicando que é possível que ocorra nos pinguins um processo de destoxificação do mercúrio orgânico por meio do selênio, porém isto não pôde foi confirmado. Ressalta-se que o atual estudo é o primeiro a relatar níveis de HgT em penas do peito da espécie P. antarctica, sendo esta informação relevante para o entendimento e conservação desta espécie de pinguim da Antártica. De modo geral o cobre (8346/32545 ng/g p.s. mín/máx) foi o elemento que apareceu em concentrações maiores se comparado ao selênio (618,7/7923,5 ng/g p.s. mín/máx) e mercúrio total (114,6/1180,2 ng/g p.s. mín/máx). Estas elevadas concentrações de cobre nas penas possivelmente se deve a incorporação via alimentação composta essencialmente de krill, que é um crustáceo de altas concentrações deste elemento essencial. Genericamente foi possível observar que todas as informações reportadas no atual trabalho, tais como as correlações entre os elementos-traço (HgT e Se) e características biológicas, mostram que as três espécies de pinguins analisadas seguem padrões distintos de distribuição de elementos-traço possivelmente porque apresentam dieta diferenciada, além disto, é provável que as características individuais influenciem nestes padrões, e por isto devem ser avaliadas para um melhor entendimento da distribuição dos elementos-traço nestes animais. Observa-se que as concentrações do elemento-traço não essencial HgT aparentemente não constituiu uma ameaça aos pinguins porque foi inferior ao nível considerado prejudicial a aves, enquanto o selênio é um elemento que deve ser constantemente monitorado pois exibiu concentrações próximas àquelas considerada danosa para aves quando incorporadas via dieta. Verificou-se que a presença dos elementos-traço não constitui uma ameaça a saúde dos Pygoscelis da Ilha Rei George, apesar disso, faz-se necessária a realização de um programa de monitoramento constante nesta região, que é uma área ainda considerada como não impactada pela ação antrópica. / This study assessed the magnitude of Antarctic penguins, genus Pygoscelis, exposure to trace elements as total mercury (THg), selenium (Se) and copper (Cu) to check some variations of these elements according to biological characteristics of the animals. To conduct this, breast feathers of Pygoscelis papua (n = 30), P. antarctica (n = 21) and P. adeliae (n = 48) were taken and analysed from seabirds collected from King George Island, Antarctica. Apparently was found lower levels of THg and Se in P. papua than in others penguins species, and this one specie also corresponded to the greater different trace element level found in Pygoscelis penguins. It was found correlation between THg and Se levels for P. antarctica and P. adeliae indicating that it is possible that the penguins can have detoxification process of the organic mercury by selenium, but this could not be confirmed. It is noteworthy that present study is the first to report THg levels in breast feathers of the species P. antarctica, being this information relevant for the understanding and conservation of this species of penguin in Antarctica. Overall, copper (8346/32545 ng / g d.w. min / max) was the element that appeared in higher concentrations compared to selenium (618.7 / 7923.5 ng / g d.w. min / max) and total mercury (114 , 6/1180, 2 ng / g d.w. min / max). These high concentrations of copper in feathers is possibly caused by incorporation through food items of the penguins, that consists mainly of krill. This crustacean also have high concentrations of this essential element. It was observed that all the information reported in this study, such as correlations between trace elements (THg and Se) and biological characteristics, show that the three penguin species follow different patterns of distribution of trace elements, and it is perhaps because they have diet differentiated. Moreover, it seems that the individual characteristics also influence these patterns, and therefore should be evaluated for a better understanding of the distribution of trace elements in these animals. It was observed that the concentrations of non-essential trace element THg apparently not constitute a threat to penguins because it was below the level considered harmful, while selenium is an element that must be constantly monitored because exhibited concentrations close to those considered potentially harmful to birds when incorporated via diet. It was found that the presence of trace elements does not constitute a threat to the health of Pygoscelis from King George Island. Nevertheless, a constant monitoring program is necessary for the region, which is still considered a preserved environment.
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Wintertime convection and frontal interleaving in the Southern OceanToole, John Merrill January 1980 (has links)
Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Meteorology, 1980. / Microfiche copy available in Archives and Science. / Vita. / Bibliography: leaves 315-325. / by John Merrill Toole. / Sc.D.
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Three-dimensional gravity analysis of the Pacific-Antarctic east Pacific rise at 36.5°S, 49.8°S and 54.2°SEnriquez, Kelly D. 23 May 1994 (has links)
Three-dimensional gravity analysis is the process of removing the predictable
components from the free-air gravity anomalies and has proven to be useful for
interpreting the subsurface structures and active processes at mid-ocean ridges. The
three-dimensional effects of the seafloor and Moho topography, assuming a constant
crustal thickness and constant crust and upper mantle densities, are subtracted from the
free-air anomalies, yielding the mantle Bouguer anomalies. Mantle Bouguer anomalies
at mid-ocean ridges are believed to be largely due to the three-dimensional thermal
structure, which can be predicted using a simple passive flow model. When the gravity
contribution from the predicted thermal structure is removed from the mantle Bouguer
anomalies, the residual mantle Bouguer anomalies are created, which represent lateral
variations in the crustal thickness and/or density variations from the assumed model.
Three-dimensional gravity analysis has been carried out over three areas along
the Pacific-Antarctic East Pacific Rise (EPR): (1) the eastern intersection of the Menard
transform with the EPR, (2) the overlapping spreading center (OSC) at 36.5°S and, (3)
the western intersection of the Raitt transform with the EPR. This geophysical analysis
provides an essential tool for understanding the subsurface crustal/upper mantle structure of the fast spreading EPR, and more specifically at transform and nontransform offsets along the EPR.
Several interesting features were observed at the eastern intersection between the
Menard transform and the EPR. The continuous nature of the residual mantle Bouguer
anomalies along the ridge axis suggests that the 60 km of ridge axis surveyed here has a
fairly uniform crustal/upper mantle structure. Significant features are not observed in
the residual mantle Bouguer anomalies at the ridge-transform intersection or along the
eastern 75 km of the Menard transform. At the ridge-transform intersection, fresh lavas
from the observed overshot ridge have filled in the transform valley and have
subsequently thickened the crust, eliminating any crustal thinning that is occurring there.
The large OSC at 36.5°S has a left-stepping offset of approximately 34 km. The
most significant feature in the gravity data from this study area is the observed low in
the mantle Bouguer anomalies which extends from the northern ridge segment, eastward
to the "inactive" rift and continued along the southern ridge segment. This gravity low
suggests that this region is underlain by thicker crust and/or hotter, less dense material.
No significant features are observed in the residual mantle Bouguer anomalies
associated with the overlap basin or the two smaller basins that border the "inactive" rift.
The western ridge-transform intersection (RTI) between the Raitt transform and
the EPR significantly differs from the Menard transform study area. A transform valley
is not observed at this RYE and neither is an overshot ridge. Instead, a transformparallel
median ridge is observed east of the RTI, and a fossil transform valley is
observed north of the RTI. A low in the residual mantle Bouguer anomalies is
associated with the fossil transform valley and the median ridge, suggesting that these
areas are underlain by thicker crust and/or less dense material. Positive residual mantle
Bouguer anomalies observed at the inside corner of the RYE suggest that this area is
underlain by thinner crust and/or colder, more dense material; while at the outside corner of the ridge-transform intersection, a residual anomaly low is observed which suggests
that the outside corner is underlain with thicker crust and/or hotter, less dense material. / Graduation date: 1995 / Figures in original document are black and white photocopies. Best scan available.
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Aspects of the biology of polar pycnogonidsRichards, Peter Robin January 1976 (has links)
The internal morphology of fixed specimens of Antarctic pycnogonids WDS examined. Theories postulated during the course of these histological studies were then tested and modified by observations on live material and specimens fixed specially for histochemistry on visits both to the Arctic and d Antarctic. Live material was also transported back to Britain from these regions and cultured in refrigerated marine aquaria. The digestive system was studied in considerable detail. It is suggested that digestion is intracellular with gut cells changing their morphology during their lifetime. Embryo cells develop into Absorptive cells which at some stage take up a glandular appearance but not a glandular function. There are therefore two gut cell types, 'Embryo' and 'Absorptive/glandular'; this is in disagreement with some previous authors who separate the latter. The rele of the gut cell in the light of present day lysosome theory is discussed and a re-interpretation of work by previous authors suggested. It is found that the digestive process is slow and the prey tastes of the species studied, catholic. Furthermore, it is found that some species can survive for long periods without appearing to feed. Suggestions are made as to the significance and mechanisms of these phenomena. Mass transport in the body cavities is considered flnd compared with that of Hydra, an animal with which previous authors have made comparisons; - their philosophy is questioned. Blood flow, heartbeat and intestine movements are also considered and suggestions for future studies made. The role of blood itself is studied a possible clotting system described. Preliminary experiments on blood electrophoresis and chromatography indicate that such techniques may be useful in clarifying some complexities of pycnogonid classification and might provide a means by which future workers in the field might better link nutritional state, mass transport, digestion and external environment conditions.
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The biogeomorphology associated with a keystone plant species in the sub-AntarcticHaussmann, Natalie Suzette 03 1900 (has links)
Thesis (PhD (Conservation Ecology and Entomology))--University of Stellenbosch, 2011. / AFRIKAANSE OPSOMMING: Min aandag is al gegee aan biogeomorfologiese interaksies in glasiale en periglasiale omgewings. Nietemin is hierdie interaksies, wat op die skeidingsvlak tussen ekologie en geomorfologie fokus, baie belangrik in hierdie omgewings, waar organismes in noue verband met die abiotiese omgewing saamleef. In hierdie tesis bestudeer ek die interaksies tussen die vaskulêre plantspesies met die hoogste voorkoms op sub-Antarktiese Marion Eiland, Azorella selago Hook. (Apiaceae), en die omringende geomorfologiese landskapsvorme, -prosesse en meettegnieke. Verder verskaf die tesis voorstelle om toekomstige geïntegreerde biogeomorfologiese navorsing te vergemaklik.
Om die gevolge van A. selago-plante vir sedimentbeweging en -verspreiding te verstaan, het ek die verspreiding van sedimentgroottes om hierdie plante gemeet deur middel van 'n kombinasie van fotografiese analise-metodes. Deur as sedimentbewegingsobstruksies te dien, het plante 'n waarneembare effek op die omringende sedimentverdeling. Dit is veral belangrik om hierdie interaksies tussen A. selago en sy omgewing te verstaan in die lig van onlangse klimaatsverandering op die eiland, omdat sedimentgrootte belangrike grondeienskappe soos waterretensiekapasiteit en vriesgevoeligheid beïnvloed.
Om die effek wat A. selago plante op die omringende mikroklimaat het beter te verstaan, is die kleinskaalse variabiliteit in grondtemperature om A. selago plante bestudeer. Grootskaalse grondligting as gevolg van fors is gemeet, ten spyte van relatief ligte forseienskappe. Dit dui daarop dat naaldys ook by temperature bo -2°C kan vorm. Wintergrondtemperature aan die oostekant van plante was effens laer en minder veranderlik as aan die westekant van plante, waarskynlik as gevolg van laer windsnelhede en/of sneeu wat ophoop aan die oostelike, lykant van plante. Die resultate benadruk dat A. selago plante 'n belangrike rol speel in die verandering van mikroklimate en dat dit belangrik is om die gevolge van sulke veranderings, soos die skep van mikrohabitatte vir grondorganismes, te verstaan.
Daar word vermoed dat positiewe plantinteraksies negatiewe interaksies oorheers in omgewings met hoe abiotiese druk. Gevolglik wys ek dat daar 'n positiewe verband bestaan tussen A. selago plante en saailinge van beide A. selago self, asook van die meerjarige gras Agrostis magellanica Lam. (Poaceae). Ek stel voor dat beide plante en klippe sade, wat deur wind, reenval en/of afdraande sedimenttransportering as gevolg van vriesprosesse vervoer word, opvang. Verder dui verhoogde A. selago saailinggetalle om plante, maar nie om klippe nie, daarop dat plante een of ander biologiese voordeel aan A. selago saailinge bied.
Dit is bekend dat die verspreidingspatrone van plantspesies as gevolg van abiotiese stresgradiente varieër. Met hierdie bevinding in gedagte, is moontlike faktore verantwoordelik vir A. selago saailinggetalle en -verspreidingspatrone, soos hoogte bo seespieël en substraatbedekking, bestudeer. Alhoewel dit wil voorkom asof daar 'n verband tussen saailinggetalle en hoogte bo seespieël is, is saailinggetalle en verpreidings meestal afhanklik van ongemeette perseel-spesifieke eienskappe.
Plante kan die omringende geomorfologie beïnvloed, maar ook geomorfologiese meettegnieke. Om die potensiaal van kosmogeniese dateringsmetodes as geomorfologiese hulpmiddels in fellfield habitatte te verken, is die akkumulasietempo van die kosmogeniese isotoop ¹ºBe onder en langs 'n A. selago plant bepaal. Die resultate dui daarop dat ¹ºBe nie ten volle in die grondprofiel behoue bly nie en verskeie potensiële redes word bespreek. Verder dui die resultate daarop dat ¹ºBe konsentrasies in fellfield habitatte versigtig geïnterpreteer moet word, aangesien A. selago plante effektief ¹ºBe opvang in hulle grondryke kern.
Om vordering in biogeomorfologie te vergemaklik, is dit belangrik om bewus te wees van die verskillende metodes wat geomorfoloë en ekoloë volg. Ekologiese benaderings is dikwels op strenger statistiese tegnieke gebaseer, terwyl geomorfoloë eerder fokus op 'n meer beskrywende benadering en teoretiese beredenering. Ek verduidelik hoekom die twee velde sulke uiteenlopende benaderings volg, benadruk moontlike struikelblokke en verskaf voorstelle om samewerking te vergemaklik. / ENGLISH ABSTRACT: There are few scientific publications that relate to biogeomorphological interactions in glacial and periglacial environments. Interactions that focus on the interface between ecology and geomorphology are very important in these environments, as a tight coupling often exists between organisms and their abiotic surroundings. In this thesis the interactions between the dominant vascular cushion plant species on sub-Antarctic Marion Island, Azorella selago Hook. (Apiaceae), and the surrounding geomorphological landforms, processes and measuring techniques were studied. In addition, the thesis provides suggestions to facilitate future integrated biogeomorphological research.
To understand the consequences of A. selago cushions for substrate movement and sorting, the grain size distribution of sediment surrounding these cushions was quantified using a combination of image analysis approaches. Through obstructing frost-related sediment transport, A. selago cushions are shown to affect the grain size sorting of the surrounding sediment. Particle size affects soil properties such as water-holding capacity and frost susceptibility. It is therefore important to understand the interactions between A. selago cushions and sediment distributions, especially in the light of recent warming and drying on the island.
Fine scale variability in soil temperature parameters was studied around cushions to improve understanding on how A. selago affects the surrounding soil microclimate. Despite the mild frost climate, extensive frost heave occurred in the study area, indicating that needle ice forms above the previously suggested required temperature of -2°C. Lower and less variable winter temperatures were found on eastern than on western cushion sides, probably as a result of lower wind speeds or leeside snow accumulation on eastern cushion sides. These research findings highlight the importance of A. selago cushions in modifying site microclimates. Such modifications could have important potential consequences, such as providing microhabitats for soil microorganisms and seedlings.
Positive plant interactions have been suggested to dominate over negative interactions in environments with high abiotic stress. Positive associations were found between A. selago and both its own seedlings and those of the perennial grass, Agrostis magellanica Lam. (Poaceae) on Marion Island. It is suggested that both cushions and rocks trap seeds dispersed by wind, runoff and/or downslope sediment transport through frost creep. In addition, increased A. selago seedling numbers around cushions, but not around rocks, suggest that cushions provide a biological nurse effect to seedlings of their own kind.
Plant species' distributions have been known to vary in response to abiotic stress gradients. In light of this, determinants of A. selago seedling distributions and abundance, such as altitude and substrate cover, were explored. Although there appears to be some altitudinal trend, seedling distributions and abundance patterns were largely attributed to unaccounted variation between sites.
Plants can affect the surrounding geomorphology, but also geomorphological measuring techniques. To explore the potential of cosmogenic dating techniques as geomorphological tools in fellfield habitats, accumulation rates of the cosmogenic isotope ¹ºBe were assessed underneath and adjacent to an A. selago cushion. The results show that ¹ºBe is not fully retained in the soil profile and various reasons are discussed. Furthermore, the results suggest that ¹ºBe concentrations should be interpreted cautiously in fellfield habitats, as A. selago cushions effectively intercept the isotope in their soil-rich core.
To facilitate the integration of geomorphological and ecological principles, as was attempted in this thesis, it is important to understand the philosophies behind the different research approaches that ecologists and geomorphologists employ. Ecologists often employ a more statistics-based approach, whereas geomorphologists focus on a more descriptive approach and reasoning based on established theories. I attempt to explain why the two fields follow such different approaches, highlight some potential challenges and provide suggestions to facilitate progress in the interdisciplinary field of biogeomorphology.
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Omega 3 fatty acids : identification of novel fungal and chromistal sourcesBroughton, Richard January 2012 (has links)
There is a wealth of scientific evidence associating the dietary intake of omega 3 long-chain polyunsaturated fatty acids with beneficial health properties. In this study, alternative natural sources of these polyunsaturated fatty acids are sought from novel low temperature isolated fungi. Over 100 low temperature isolated fungi were screened for very long chain polyunsaturated fatty acids (VLCPUF As), such as C20:5 n3 and C22:6 n3. Of those screened, only ten fungi were capable of VLCPUFA production, with Mortierella the predominant VLCPUF A producing species. Four Oomycete species were also capable of VLCPUF A production. It is thought that only basal fungal lineages, such as species from the Chytridiomycota and Zygomycota, are capable of VLCPUF A production. It was also found that VLCPUF As are not essential for growth at low temperatures, as Penicillium rugulosum, capable of producing 'fatty acids no longer or more unsaturated than C18:3 n3, demonstrated over 2 g of biomass per 100 ml of broth when grown at 5°C. This indicates that trienoic fatty acids are sufficient for maintaining membrane fluidity, although other factors may play a role in P. rugulosum's low temperature growth. Comparatively, VLCPUFA producing Mortierella species produced 200-250 mg of biomass, whereas the majority of non- VLCPUF A producing isolates produced 106-115 mg of biomass per 100 ml of broth. The total lipid unsaturation indices of nine isolates grown under three temperature regimes showed that the lowest growth temperature, 5°C, produced the highest un saturation index value III SIX of the organisms. 15°C produced the highest unsaturation index value in two of the isolates. This suggests that temperature has an effect on fungal lipid composition, and that lower temperatures may increase lipid unsaturation levels. It was also found that the ~6 elongase, initially identified from Mortierella alpina, is indicative for VLCPUF A producing fungi. The genomic conserved sequence found within ~6 elongases was used to develop primer sets that could be used with a PCR based methodology to screen fungal isolates for VLCPUF A production. The method successfully identified VLCPUF A producing Mortierella and Allomyces species, and was not found to amplify non-Ad elongases. Finally, recombinantPhaffia rhodozyma strains were developed using the ~5 desaturase and ~6 elongase from Mortierella alpina. The fatty acid profiles of the recombinant strains displayed novel fatty acids such as C20:2 n6 and C20:3 n3, and putatively, C18:2 ~5, 9 and C18:3 ~5, 9, 12 which correlated with the inserted genes.
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Communicating air : alternative pathways to environmental knowing through computational ecomediaPolli, Andrea January 2011 (has links)
This dissertation, Communicating Air: Alternative Pathways to Environmental Knowing through Computational Ecomedia, is the culmination of an art practice-led investigation into ways in which the production of ecomedia may open alternative pathways to environmental knowing in a time of urgent climate crisis. This thesis traces the author’s artistic, personal and political development across the period of study and presents an extended argument for greater public engagement with weather and climate science, greater public and private support for long-term collaborations between media art and climate science, and increased public open access to global weather and climate monitoring and computationally modelled data.
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The provision of health care in remote hostile environmentsBrebner, John Alexander January 1990 (has links)
The health care of those who work in remote places associated with hostile environments is reviewed, concentrating on the offshore oil industry and Antarctic populations. An understanding of associated environmental hazards is essential for adequate health care and particular attention is paid to the hyperbaric environment and to environmental heat and cold. The basic medical problems in remote health care are evaluated in three related studies. The first examines 2,162 personnel who required medical evacuations from the offshore structures of four North Sea operating companies, the second with 5,894 presentations from offshore at the A&E department of Aberdeen Royal Infirmary, while the third examines 100 annual medical reports from British Antarctic Survey stations.
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