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  • 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.
71

Melbourne's indigenous plants movement: The return of the natives

Tarrant, Valerie M, valerie.tarrant@deakin.edu.au January 2005 (has links)
This thesis examines Greater Melbourne’s indigenous plants movement from the 1930s to the early twenty first century. It demonstrates the important scientific and educational role of the public intellectual, Professor John Turner, and of the Melbourne University Botany School which he led for thirty five years. The case study of the movement within the City of Sandringham and its successor the City of Bayside reveals how the inhabitants of an urbanised are responded to threats to the indigenous trees and wildflowers of their neighbourhood, stimulating botanists to assist them and using political means in order to achieve their conservation objectives. The thesis draws upon a range of local archives, conservation literature and private papers.
72

Hög köttkonsumtion och hur den kan påverka risken för folksjukdomar : en litteraturstudie baserad på kvinnor / High meat consumption and how it may affect the risk of endemic diseases : A literature study based on women

Waldenby, Anna, Svanberg, Karin January 2012 (has links)
Bakgrund: Vi äter allt mer kött. Tidigare forskning har visat på samband mellan högt köttintag och bland annat hjärt- och kärlsjukdomar och cancer. Information om skyddsfaktorer som minskar risken för folksjukdom är begränsad. Forskning om hälsa och sjukdom hos kvinnor är begränsad och därför behövs kvinnors hälsa lyftas fram. Syfte: Litteraturstudiens syfte var att undersöka huruvida ett högt köttintag kan påverka risken för folksjukdomar hos kvinnor. Resultat: Resultatet tyder på en koppling mellan ett högt intag av rött och bearbetat kött och folksjukdomar hos kvinnor. Samband har funnits mellan högt köttintag och bröstcancer, diabetes och hjärt- och kärlsjukdomar. Riskerna har visat sig kunna minska vid ett utbyte från det röda och bearbetade köttet till andra animaliska proteinkällor eller vegetabilier. Diskussion: Kosten bör vara en viktig förebyggande insats när det gäller folksjukdomar. Kostråd för kvinnor bör innefatta ett lågt intag av rött och bearbetat kött och en kost rik på frukt, grönsaker och protein från andra källor än rött och bearbetat kött. Slutsats: Tydliga och enhetliga kostråd bör tas fram för att minska folksjukdomarna hos den kvinnliga befolkningen. / Background:Our meat intake increases. Previous research has shown the connection between high meat intake, including cardiovascular disease and cancer. Information on appropriate diet to reduce the risk of endemic disease is limited. Research on health and disease in women is limited and, therefore, women's health must be taken seriously. Objective: The aim of the literature study was to investigate whether a high meat intake may influence risk of endemic diseases in women. Results: The results suggest a link between a high intake of red and processed meat and endemic diseases in women. Correlations have been found between high meat intake and breast cancer, diabetes and cardiovascular disease. Exchanges from the red and processed meat to other sources of animal protein and vegetables have been shown to reduce the risk of endemic diseases. Discussion: Advice on diet should be an important prevention strategy on endemic diseases. Advice on diet for women should include a low intake of red and processed meat and a diet rich in fruits, vegetables and protein from sources other than red and processed meat. Conclusion: Clear and consistent dietary guidelines should be developed to help reduce the endemic diseases of the female population.
73

Effects Of Climate Change On Biodiversity: A Case Study On Four Plant Species Using Distribution Models

Beton, Damla 01 July 2011 (has links) (PDF)
Conservation strategies are mainly focused on species existing in an environment shaped by natural and anthropogenic pressures. Yet, evidence shows that climate is changing faster than ever and expected to continue to change in the near future, which can be devastating for plants with restricted ranges. Turkey harbors many endemic species that might be affected from these changes. However, available data is scarce and biased, complicating the anticipation of future changes. Aim of this study is to improve our understanding of endemic species distributions and forecasting effects of climate change via species distribution modelling (SDM). The study is based on two Anatolian (Crocus ancyrensis and Crataegus tanacetifolia) and two Ankara (Salvia aytachii and Centaurea tchihatcheffii) endemics. Independent presence and absence data (ranging between 19-68 and 38-61, respectively) for each species was collected through fieldwork in and around the Upper Sakarya Basin in 2008 and 2009. With the software Maxent, SDMs were performed by using 8 least correlated environmental features and random presence records (of which 25% were used for confusion matrix). SDMs for current distributions of C. ancyrensis, C. tchihatcheffii and C. tanacetifolia were reliable enough for future extrapolations despite errors originating from scale, non-equilibrium status and biotic interactions, respectively. The model for S. aytachii failed due to absence of limiting factor (soil type) in the model. Future projections of those three species modelled using CCCMA-CGCM2 and HADCM3 climate models indicated three possible responses to climate change: (1) Extinction, especially for habitat specialists / (2) Range expansion, especially for generalist species / and (3) Range contradiction, especially for Euro-Siberian mountainous species. Species modelling can be used to understand possible responses of plant species to climate change in Turkey. Modelling techniques should to be improved, however, especially by integrating other parameters such as biotic interactions and through a better understanding of uncertainties.
74

Provenance, lifespan, and phylogeny : testing a conceptual framework for plant community management /

Benfield, Cara D. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 31-39). Also available on the World Wide Web.
75

Dentist, Doctor, Dean : Professor Sir Charles Hercus and his record of fostering research at the Otago Medical School, 1921-1958

Le Couteur, Claire Elizabeth January 2014 (has links)
This thesis investigates the development of medical research at the Otago Medical School in Dunedin, New Zealand under Sir Charles Hercus, Dean from 1937-1958. It also explores his interest and participation in research from his student days and the years before becoming Dean, as well as the influence of the First World War on his career. The study draws upon unpublished material in New Zealand archives and a collection of student projects investigating public health issues. Hercus, as Professor of Public Health and Bacteriology incorporated these projects into the curriculum in the early 1920s. The thesis uses many original papers published in scientific and medical journals by Hercus and his colleagues at the School. Building on a base of archival material including contemporary newspaper accounts, which have lately become available on the Papers Past website, this thesis draws together the individual disease studies undertaken by other thesis writers to give an account of Hercus’s achievements in fostering medical research. A key finding of this thesis is that Hercus was instrumental in building up the research capability of the School. He accomplished this through his own investigations and by helping to establish the New Zealand Medical Research Council. The thesis illustrates the multitude of studies that Hercus undertook personally or facilitated others to pursue, beyond the elimination of endemic goitre, for which he perhaps is best known. Another outcome of this study is an understanding of the difficult path that scientists faced in the early years of the twentieth century in New Zealand if they wished to carry out research. This thesis follows the origins of the Department of Scientific Research in the 1920s and the frequent collaboration Hercus made with scientists outside of the School. It will also demonstrate Hercus’s compassion and foresight in employing several Jewish refugee doctors as researchers at the School, who brought expertise into the research programmes. The era was one of great interest in improving the health and wellbeing of a generation affected by wars and deprivation caused by them. A key finding of this thesis is that researchers at the School took steps to mitigate these through making New Zealand more self-sufficient in foodstuffs and to improve the national diet. As well, Hercus lobbied for the establishment of a School of Physical Education within the university to improve the physical fitness of the population.
76

Immune modulatory effect of Dichrostachys cinerea, Carpobrotus dimidiatus, Capparis tomentosa and Leonotis leonurus

Hurinanthan, Vashka January 2009 (has links)
Submitted in fulfillment of the requirements for the Degree of Master of Technology: Biotechnology, Durban University of Technology, 2009. / Dichrostachys cinerea, Carpobrotus dimidiatus, Capparis tomentosa and Leonotis leonurus are all plants that are indigenous to South Africa. These plants are used in traditional medicine to treat various ailments. However, there is little or no scientific data to justify these traditional uses. Furthermore, it is difficult to reconcile traditional knowledge with scientific evidence because of the overwhelming targeting of signal-responsive systems by plant defensive compounds, multiple sites of action and the connectedness of the signaling pathways, which provide many cures and have pleiotropic effects. In order to evaluate the action spectrum of these plants, and validate its widespread use, this research evaluated the antibacterial, antioxidant, anti-inflammatory, anti-mosquito and immunomodulatory properties of these plants. Antimicrobial activity of the extract was determined by evaluating the bactericidal and fungicidal action using the agar disc diffusion assay. Anti-oxidative properties of the extracts were tested using the DPPH photometric assay. Anti-inflammatory properties were carried out using the 5-lipoxygenase assay. The larvicidal, repellency and insecticidal assay was determined against A.arabiensis. The safe use of these plant extracts was determined by evaluating toxicity, a brine shrimp lethality assay and an in vitro cell culture system using human myelogenous leukemia cell line. Potential carcinogenic activity was evaluated using the Ames Salmonella Mutagenecity assay. The immunomodulatory activity of the extracts on human peripheral blood mononuclear cells 6 was evaluated on freshly harvested lymphocytes using the MTT assay. Cytokine response was evaluated by measuring the secretion of interferon-gamma and interleukin-10. Elucidation of the B cells, T cells, activated T cells, CD 4+, CD 8+ and NK cells was performed by flow cytometry. The extracts showed anti-microbial activity against Escherichia coli, Pseudomonas aeruginosa, Klebsiella oxytoca, Salmonella typhimurium, Serratia marcescens, Bacillus cereus and Tricoderm sp. The highest activity was shown by methanolic and aqueous extracts of L. leonurus leaves followed by methanolic and aqueous extracts of D. cinerea. Extracts of C. tomentosa and D.cinerea demonstrated a higher degree of free radical scavenging than rutin, which was used as a standard indicating that these plants have strong antioxidant properties. None of the plants showed significant anti-inflammatory activity when compared to NDGA. In the anti-mosquito assays, the extracts showed strong repellency and insecticidal activity. L. leonurus extracts demonstrated the highest insecticidal and repellency activity against the mosquito, and was also found to cause ‗knockdown‘ and mortality. The extracts display no toxicity, cytotoxicity and mutagenicity. The immunological studies for immune modulation showed that the methanol extracts of these plants induce a Th1- predominant immune response because they significantly suppressed the secretion of IL-10 and augment IFN-γ production, which are hallmarks used to indicate a stimulation of the innate immune response. This study also provides new information, with respect to the potential use of these plants in producing a mosquito repellent and an immunostimulant.
77

Dynamics of Multi-strain Age-structured Model for Malaria Transmission

Farinaz, Forouzannia 22 August 2013 (has links)
The thesis is based on the use of mathematical modeling and analysis to gain insightinto the transmission dynamics of malaria in a community. A new deterministic model for assessing the role of age-structure on the disease dynamics is designed. The model undergoes backward bifurcation, a dynamic phenomenon characterized by the co-existence of a stable disease-free and an endemic equilibrium of the model when the associated reproduction number is less than unity. It is shown that adding age-structure to the basic model for malaria transmission does not alter its essential qualitative dynamics. The study is extended to incorporate the use of anti-malaria drugs. Numerical simulations of the extended model suggest that for the case when treatment does not cause drug resistance (and the reproduction number of each of the two strains exceed unity), the model undergoes competitive exclusion. The impact of various effectiveness levels of the treatment strategy is assessed.
78

Patterns of animal endemism in the Maputaland-Pondoland-Albany biodiversity hotspot.

Perera, Merennage Sandun Jayalal. 12 September 2014 (has links)
The Maputaland-Pondoland-Albany (MPA) hotspot, as is the case of all such global biodiversity hotspots, has primarily been recognised based on its high floristic endemism and delimited intuitively. Boundaries of global biodiversity hotspots have seldom been empirically tested in terms of species distribution patterns and only a few have been examined for patterns of animal endemism. This thesis presents the results of a zoogeographical study of all five major vertebrate groups and selected invertebrate groups in south-eastern Africa, refining the delimitation of the MPA hotspot and identifying areas and centres of endemism within and around it. It also provides zoogeographical regionalisation schemata for the whole of south-eastern Africa. The study employed methods of, (a) preliminary qualitative identification of “Endemic Vertebrate Distributions”, (b) phenetic clustering of operational geographical units based on species incidence matrices, using the Jaccard’s coefficient of similarity and the Unweighted Pair-Group Method using Arithmetic means (UPGMA) clustering algorithm, (c) Parsimony Analysis of Endemicity, and (d) ArcGIS-based mapping of various measures of endemism (e.g. narrow endemism and weighted endemism). The results reveal that the MPA hotspot, though defined so due to its exceptional floristic endemism, is a hotspot for the endemism of animals too, especially for the herpetofauna and invertebrate groups like the velvet worms, land snails and many others. But the current boundary of the hotspot is arbitrarily defined and not exactly matching the patterns of animal endemism (and, likely, neither those in plants). Hence, a greater Maputaland-Pondoland-Albany (GMPA) region of animal endemism is proposed as a broad priority region of conservation concern, while centres of endemism within the GMPA are identified and patterns of quantitative measures of endemism are mapped. The study also proposes a zoogeographical regionalisation placing the GMPA and Highveld regions at the province rank in the global zoogeographical hierarchy, within the south east African dominion, also describing zoogeographical districts and assemblages nested within each. Results from the vertebrate and invertebrate analyses reveals the possibility of a common zoogeographical regionalisation for south-eastern Africa. The study emphasises the importance of quantitative biogeographical methodologies in conservation biogeography, in addition to their uses in the theoretical/descriptive biogeography. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2013.
79

Functional design opportunities for water conservation through native landscape restoration in southwestern Idaho, U.S.A.

Grambo, Andrew A. January 2004 (has links)
This creative project inspected the design of water conserving landscapes by restoring native vegetation. Water conserving design principles discovered in the background research were applied to the redesign of the Old Fort Boise Park in Parma, Idaho. Important issues that were explored included discussing the need for water conserving landscape designs that result in functional spaces that meet the needs of intended users. The main focus of water conservation was implemented by using native plants that typically require less water than non-native species. The project developed a park master plan that could demonstrate to Idaho residents that native plants, when carefully sited, result in lower maintenance, aesthetically pleasing visual qualities, environmentally sensitive performances and could be integrated into landscapes on private or public properties. Rather than viewing the Idaho native plants as unattractive and dull, this project explored the idea that under cultivation and as part of the site character a carefully designed water conserving naturalized landscape has a beauty unsurpassed by traditional landscapes. The park redesign also employed educational and interpretive systems wherein native plants were highlighted and identified. These educational and interpretive systems could assist park users, especially local residents, in familiarizing themselves with many of the beautiful native species that are common in the surrounding deserts, prairies, hills and mountains. The creative project examined one particular site, while it developed principles and concepts applicable to other sites throughout the Great Basin Region. / Department of Landscape Architecture
80

Dynamics of Multi-strain Age-structured Model for Malaria Transmission

Forouzannia, Farinaz 22 August 2013 (has links)
The thesis is based on the use of mathematical modeling and analysis to gain insightinto the transmission dynamics of malaria in a community. A new deterministic model for assessing the role of age-structure on the disease dynamics is designed. The model undergoes backward bifurcation, a dynamic phenomenon characterized by the co-existence of a stable disease-free and an endemic equilibrium of the model when the associated reproduction number is less than unity. It is shown that adding age-structure to the basic model for malaria transmission does not alter its essential qualitative dynamics. The study is extended to incorporate the use of anti-malaria drugs. Numerical simulations of the extended model suggest that for the case when treatment does not cause drug resistance (and the reproduction number of each of the two strains exceed unity), the model undergoes competitive exclusion. The impact of various effectiveness levels of the treatment strategy is assessed.

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