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Being / becoming the âCape Town flower sellersâThe botanical complex, flower selling and floricultures in Cape TownBoehi, Melanie Eva January 2010 (has links)
<p>This mini-thesis is concerned with histories of flower selling in Cape Town. Since the late 19th century, images and imaginings of the flower sellers in Adderley Street and to a lesser degree in other areas of the city attained an outstanding place in visualisations and descriptions of Cape Town. The flower sellers were thereby characterised in a particularly gendered, racialised and class-specific way as predominantly female, coloured and poor. This characterisation dominated to an extent that it is possible to speak of a discursive figure of the ÌÌCape Town flower sellersÌÌ. In tourism-related media and in personal memoirs, the ÌÌCape Town flower sellersÌÌ often came to represent both the city and the inhabitants of Cape Town. The images and imaginings of the &lsquo / Cape Town flower sellers&rsquo / can partly be traced back to representations of ÌÌÌÌflower girlsÌÌ in fictional stories, paintings, photographs and film in Europe, particularly in Great Britain. In Cape Town, this European discourse about flower selling developed in a specific way within colonial, apartheid and post-apartheid contexts.</p>
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Econometric Analysis of Labour Market InterventionsWebb, Matthew Daniel 08 July 2013 (has links)
This thesis involves three essays that explore the theory and application of econometric analysis to labour market interventions. One essay is methodological, and two essays are applications. The first essay contributes to the literature on inference with data sets containing within-cluster correlation. The essay highlights a problem with current practices when the number of clusters is 11 or fewer. Current practices can result in p-values that are not point identified but are instead p-value intervals. The chapter provides Monte Carlo evidence to support a proposed solution to this problem.
The second essay analyzes a labour market intervention within Canada--the Youth Hires program--which aimed to reduce youth unemployment. We find evidence that the program was able to increase employment among the targeted group. However, the impacts are only present for males, and we find evidence of displacement effects amongst the non-targeted group. The third essay examines a set of Graduate Retention Programs that several Canadian provinces offer. These programs are aimed at mitigating future skill shortages. Once the solution proposed in the first essay is applied, I find little evidence of the effectiveness of these programs in attracting or retaining recent graduates. / Thesis (Ph.D, Economics) -- Queen's University, 2013-07-05 15:56:33.805
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The spatial ecology of lion (Panthera leo) and spotted hyaena (Crocuta crocuta) in Hluhluwe-iMfolozi Park : implications for the African wild dog (Lycaon pictus.Graf, Jan Andreas. January 2008 (has links)
The ecological role of apex predators in ecosystems is increasingly recognized not only as a result of their affects on prey species, but also on the numbers and behaviour of other predator species within their guilds. In an African context, dominant apex predators such as lions (Panthera leo) and spotted hyaenas (Crocuta crocuta) have been implicated in limiting endangered intraguild species such as wild dogs (Lycaon pictus) via direct intraguild interactions, such as interference and predation. As a result of this it has been predicted that spatial and temporal refugia are critical for wild dogs to co-exist with lions and spotted hyaenas. Whether such refugia are actually present within small protected areas, such as Hluhluwe iMfolozi Park (HiP), within which these three species co-exist, has been questioned. For wild dogs, interference or predation refugia may be equated to areas or periods which contain a relatively low level of encounter probability with spotted hyaenas and lions respectively. By combining well established field research techniques, such as radio telemetry and audio playbacks, with novel geographic information system tools, I investigated the two key drivers of the probability of encounter with spotted hyaenas and lions, namely density and utilization intensity. Results from the analyses showed that substantial spatial and temporal variation existed in the utilization intensity of lions, as well as the density of both lions and spotted hyaenas, at short and intermediate time scales, in HiP. The spatial scale across which these patterns resolved appear to be well suited to the movement capabilities of wild dogs. This indicated that wild dogs may be able to exploit such areas of temporary lower density and/or utilization intensity, suggesting the dynamic nature of refugia involved in the interactions within these two species-pairs. Results from the lion analyses further suggest that groups rather than individuals are the basic units around which intraguild interactions of social predator and prey species should be investigated, and that social grouping in combination with predator territoriality may stabilize intraguild interactions. An important prediction emerging from this work is that wild dogs, or other subordinate African large predator species, may be forced to trade-off safety from hyaena interference vs. safety from lion predation. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2009. / National Research Foundation, The Green Trust (WWF–SA), The Wildlands Conservation Trust, University of KwaZulu-Natal, The Endangered Wildlife Trust, Smithsonian Institution, Sichel Family Endowment, Friends of the National Zoo, THRIP, Wild about Cats, Hluhluwe Tourism Association, Bateleurs, Third World Academy of Science, The Wild Dog Foundation, and The Sally Club.
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The effects of captivity on display-based communication and social interaction in the captive African wild dog (Lycaon pictus)Tighe, Emily Jayne January 2013 (has links)
The obligate cooperative nature of African wild dogs (Lycaon pictus), unique among social canids, is thought to be driven by high levels of interspecific competition and intra-guild predation with other large socially-organised predators. Research exploring how wild dogs maintain social bonds through social communication, while avoiding detection from potential competitors, is therefore vital for understanding this species. While olfactory and vocal communications are well represented in the literature concerning L. pictus, these channels of communication pose significant risks to wild dog survival, as they are inherently susceptible to eavesdropping by unintended receivers. In comparison, display communication, which requires visual contact between the signaller and receiver, poses comparatively less risk of attracting the attention of eavesdroppers. In spite of this, few studies have explored the use of display communication in wild dogs, leaving its potential significance in maintaining social bonds within packs unexplored. Using video analysis, I investigate how display communication and subsequent social interaction are affected by several pressures of the captive environment. Captivity did not appear to affect the presence of many social display types also used by free-ranging wild dogs. However, sexual behaviour was absent from the study groups, likely due to the use of contraception and pack sex composition. The effects of pack sex composition (single-sex versus mixed-sex) revealed that while the frequencies and durations of many social behaviours were not affected by sex composition, the distribution of social interactions did differ depending on group structure. Here, a highly related, single-sex group was more stable than a highly related, mixed-sex group of the same size. Differences in the captive management strategies, specifically enclosure size and feeding regime, of the two packs, may explain the behavioural differences observed. The death of a pack member permitted investigation of the effects of death on social interactions. While many of the social interactions were unaffected by the death, behaviours relating to the formation and maintenance of social dominance and social hierarchy increased after the dog’s death. The distribution of social interactions was non-random, suggesting that individuals were reorganising the social structure of the pack during this period. Finally, a small study into the effects of simultaneously added enrichments in the pack (post death) revealed that enrichment reduced the frequencies of dominance behaviours and allowed for a more even distribution of social interaction within the pack. This demonstrates how enrichment may potentially be used to reduce aggression within captive animals. Overall, this research reveals that display-based communication is important for the maintenance of sociality in captive African wild dogs. To better understand this endangered species, future studies in free-ranging populations should include this channel of communication.
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The physiological and biomechanical assessment of free ranging sports dogsWills, Alison P. January 2013 (has links)
No description available.
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Something like wilderness: a journey into the heart of the tundraKingsley, Jennifer 18 July 2011 (has links)
Something Like Wilderness: A Journey into the Heart of the Tundra is a work of
creative non-fiction that chronicles Jennifer Kingsley’s 54-day canoe expedition down
Nunavut’s Back River in the summer of 2005. This manuscript explores the themes of
wilderness and belonging, and it investigates the notion of intersecting journeys.
Something Like Wilderness seeks to engage readers with a compelling story while
articulating some of the ideas we have about wild places. / Graduate / 10000-01-01
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Activity and aggression in captive blue-winged teal (Anas discors)Stoddart, Ruth (Ruth Ellen) January 1985 (has links)
No description available.
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Klinische Untersuchungen zum Frakturgeschehen bei einheimischen Wildvögeln unter besonderer Berücksichtigung konservativer und operativer TherapiemaßnahmenHerrmann, Thomas Josef 05 June 2009 (has links) (PDF)
Im Rahmen der vorliegenden Arbeit wurden die in der Fachliteratur am häufigsten beschriebenen Formen der aviären Frakturtherapie anhand von 147 Wildvogelpatienten mit 237 gebrochenen Knochen im Hinblick auf ihre Einsatzmöglichkeiten, den Stellenwert, sowie auf Vorteile und Risiken der jeweiligen Methoden überprüft und die in der Literatur getroffenen Aussagen den Ergebnissen der eigenen Untersuchungen gegenübergestellt. Weiterhin wurden die publizierten Informationen bezüglich therapiebegleitender Maßnahmen einer kritischen Prüfung unterzogen und um die eigenen Erkenntnisse ergänzt. Rund 55 % der therapierten Wildvögel konnten nach Abschluß der klinischen Versorgung ausgewildert werden, wobei die therapeutische Erfolgsquote von Patienten mit frischen Frakturen und denjenigen, deren Frakturereignis wenige Tage zurücklag nur unwesentlich differierte. Demgegenüber wiesen Tiere mit älteren oder bereits in Heilung befindlichen Knochenbrüchen eine schlechte Prognose auf. Fast 27 % der Vögel verstarben während der Behandlung an den Folgen ihres Traumas oder einer Begleiterkrankung, etwas mehr als 13 % wurden aufgrund eines unbefriedigenden Heilungsverlaufs oder Therapieversagens euthanasiert und in etwa 5 % der Fälle reichte das erzielte Ergebnis zur Wiedereingliederung in die freie Wildbahn nicht aus. Von den untersuchten Therapiemethoden erwies sich lediglich die intramedulläre Versorgung mittels kurzer Polyacrylstäbe nach der „Shuttle-Pin“-Methode sowie die Kombination dieser Implantate mit Knochenzement bei Patienten unter 300 g Körpergewicht als problematisch. Bei einem der auf diese Weise behandelten Patienten wurde zudem eine therapieresistente Osteomyelitis als Folge einer Fremdkörperreaktion auf das eingebrachte Material dokumentiert. Positive Erfahrung konnte in zwei Fällen mit der Verwendung eines die Markhöhle weitestgehend ausfüllenden Polyacrylstabes bei ausgedehnten Splitterfrakturen gesammelt werden – eine bislang nicht beschriebene Variante bei der Versorgung mit Markraumimplantaten. Sowohl die Therapie der geschädigten Knochen mit einem modifizierten Fixateur externe bei geeigneter Frakturcharakteristik, als auch die Markraumnagelung mit Kirschner-Drähten erbrachten zumeist die angestrebten Ergebnisse. Der in der Literatur häufig betonte Vorteil kurzer intramedullärer Implantate, wie auch des Fixateur externe gegenüber einer Markraumnagelung mit Stahlstiften aufgrund einer früheren Beübungsfähigkeit der verletzten Gliedmaße konnte anhand der eigenen Ergebnisse nicht bestätigt werden. Klinische Vorteile infolge einer ungehinderten endostalen Kallusbildung bei Verwendung des Fixateur externe im Vergleich zu intramedullären Implantaten waren nicht zu ermitteln. Die Zeitdauer bis zur Auswilderung der Patienten war in der überwiegenden Zahl der Fälle weniger von der Therapieform, als vielmehr von Frakturausmaß und -lokalisation bestimmt. Die Ergebnisse der konservativen Behandlung waren – eine entsprechende Eignung der Fraktur für das Verfahren vorausgesetzt – bei vergleichsweise geringem Risiko den operativen Methoden zumindest ebenbürtig. Für eine chirurgische Versorgung von Schultergürtelfrakturen ergab sich keine zwingende Indikation; selbst hochgradig dislozierte Coracoidfrakturen konnten mittels konservativer Behandlung funktionell wieder hergestellt werden. Die röntgenologische Kontrolluntersuchung in siebentägigen Intervallen während der ersten 3 Behandlungswochen bewährte sich dabei im Hinblick auf das zeitnahe Befunden von Therapiezwischenfällen, ausbleibenden Therapieerfolgen und insbesondere zur frühzeitigen Diagnose entzündlicher Knochenveränderungen. / This study examined the methods of avian fracture therapy most commonly described in scientific literature in regard to their usability, their significance/value as well as their advantages and risks. For this purpose 147 wild birds with 237 fractured bones were treated with different methods, depending on the type of fracture. The results were compared to relevant statements found in specialist literature. In addition, published information about supportive treatment was analysed and supplemented with specific additional findings. It was possible to release about 55% of the treated wild birds back into the wild after therapy. The rate of success in therapy showed little difference between patients with fresh fractures and those with fractures that had occurred a few days previously. In contrast to this, animals with older fractures or fractures that were already in an advanced stage of untreated healing process showed a poor prognosis. Almost 27% of the birds died during therapy as a consequence of the initial trauma or accompanying diseases, a little more than 13% had to be euthanized because of an unsatisfactory healing process or failure of fracture repair and in about 5% of the cases the results were not sufficient for rehabilitation into the wild. Among the examined methods of therapy only intramedullary application of short polyacryl rods with the shuttle pin technique and the combination of these implants with bone cement in patients with a body-weight below 300g showed unsatisfactory results. One patient treated by this method developed a therapy-resistant osteomyelitis as a consequence of a foreign-body reaction. Positive results were achieved in two cases with the use of a polyacryl rod filling most of the bone cavity in extended comminuted fractures – a variation of internal fixation not previously described. Treatment with a modified external fixator as well as intramedullary fixation with Kirschner wires resulted in the required outcome in most cases whereas unimpaired endosteal callus formation, often associated with the use of an external fixator, did not result in clinical advantages. Trials did not confirm an earlier return to function by the use of short intramedullary implants or of the external fixator compared to internal fixation with intramedullary pins, which is often emphasised in scientific literature. In most cases duration of hospitlisation and of captivity depended on the extent and site of bone injury rather than on method of therapy. Results of conservative treatment and surgery were similar in terms of low risk – as long as the method of therapy matched the type of fracture. There was no requirement for surgical therapy of fractures of the shoulder girdle. Even severely dislocated fractures of the coracoid returned to normal function through conservative treatment. Weekly radiological examination at intervals of seven days during the first three weeks of therapy proved essential to identify early complications in the healing of the fracture, failure in the healing process, or, in particular, early diagnosis of osteomyelitis.
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Mechanisms of herbicide resistance in wild oats (Avena spp.) / Chanya Maneechote.Maneechote, Chanya January 1995 (has links)
Bibliography : leaves 159-184. / xv, 191 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This study found at least three mechanisms of resistance to the acetyl coenzyme A carboxylase (ACCase)-inhibiting herbicides. A modified target -site was responsible for moderate and high resistance to herbicides at the whole plant level. Enhanced herbicide metabolism and reduced translocation of herbicide to the target site was observed in one resistant biotype each. / Thesis (Ph.D.)--University of Adelaide, Dept. of Crop Protection, 1996
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The ecology and conservation biology of the endangered African wild dog (Lycaon pictus) in the Lower Zambezi, ZambiaLeigh, Kellie A January 2006 (has links)
Doctor of Philosophy / The African wild dog (Lycaon pictus) is one of Africa’s most endangered carnivores. Previous research into this species has focussed on the largest extant populations in Africa. However, there are a large number of relatively small populations (20 to 50 dogs) distributed across Africa, which represent an important component of the diversity of the species and its remaining habitat. This study investigated the status of a small population of wild dogs in the Lower Zambezi area in Zambia. Objectives focussed on assessing population dynamics and identifying causes of decline. Research was carried out over a broad range of topics in an effort to provide comprehensive information for conservation management of the population. The scope of the project was divided into five sections: 1) Demography and pack dynamics were assessed to identify the structure and status of the population, and the main causes of mortality. 2) An assessment of habitat types and related ecological factors was carried out to determine wild dog habitat utilisation in relation to vegetation type, prey densities and hunting success in each area. 3) The effects of interpredator competition on wild dog population dynamics was investigated, specifically, the effects of lions (Panthera leo) and spotted hyaenas (Crocuta crocuta). 4) Genetic analyses were carried out to assess the historic and contemporary genetic variability of the population, and to define patterns of geographic structuring and population differentiation. 5) Results were combined to assess the viability of the population and recommend conservation management strategies. Snaring was identified as the most important cause of adult mortality, and a threat to wild dog population persistence. Inbreeding avoidance led to the emigration of adult males and females from the area and appeared to be a substantial contributor to population decline. Limited mate selection corresponded with neither sex displaying philopatry and large dispersal distances effectively removed adults from the population. This result has important implications for the management of small populations, whereby lack of mate choice may increase dispersal distances and thereby increase edge effects on populations, regardless of home range sizes. Home range sizes were related to den locations in remote areas of the Zambian Escarpment, which was used as a breeding refuge area. The Zambezi River and Zambian Escarpment appeared to be effective barriers to wild dog home range movements. The study area contained a diversity of habitats on the alluvial terraces of the river valley floor. There was a high density of impala (Aeypceros melampus), which formed the main prey base for the wild dog population. Studies of other populations have found that wild dogs often avoided areas with high competing predator densities, which corresponded with high prey density areas. In contrast to those findings, the Lower Zambezi wild dog population showed a strong preference for high prey density areas. This population also showed only temporal avoidance of high lion density areas. Low lion density areas were preferred during breeding periods, while moderate to high lion density areas were preferred during non-breeding periods. Direct predation of adult wild dogs by lion and spotted hyaenas was rare. Kleptoparasitism of wild dog kills by either competing predator species was also rare. Predator competition was not considered to be an important determinant of population decline. The Lower Zambezi population suffered from a loss of heterozygosity, low allelic richness, and there was significant evidence of a recent population bottleneck. The population did not contain any new mtDNA haplotypes, nor any unique alleles on the commonly used microsatellite loci, but was differentiated from African wild dog populations in other regions. There was evidence of historical and recent gene flow between the Lower Zambezi and the neighbouring southern African populations of Hwange and Okavango. This was the first study to show a loss of genetic variability in a free-ranging African wild dog population. Although more immediate anthropogenic and demographic factors were the critical determinants of population decline, the loss of genetic variability has important implications for the conservation of the remaining small and fragmented wild dog populations in Africa. Results showed that due to its small size the population is likely to have suffered from inverse density dependence and Allee effects on dispersal and reproductive success. Management recommendations focussed on mitigating anthropogenic causes of mortality, and improving connectivity with a larger, potential source population to increase the probability of successful dispersal and to restore genetic diversity. The high density prey base, small home range sizes and low levels of interpredator competition detected in this study suggest that the area has the capacity to support a large and potentially viable population of wild dogs if appropriate management strategies are implemented.
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