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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.
61

Bacterial n-nitrosation and nitrite reduction in the model organism Neisseria subflava

Sowerby, Zoe January 1997 (has links)
No description available.
62

Skogspedagogen : En faktaskur om djur och natur

Fromell, Ebba, Söderberg, Sofie January 2016 (has links)
No description available.
63

Flora of Wabaunsee county, Kansas

Maus, Pearl Marie January 1928 (has links)
Call number: LD2668 .T4 1928 M31 / Master of Science / The work upon which this thesis is based was done in Wabaunsee County, Kansas, during the growing seasons of 1926-1927. It is my purpose to give in this paper a list of the specieis of plants in the county with some account of their distribution, habitat and time of first flowers or fruiting. As early as 1896, some collections were made in Wabaunsee County by J.B. Norton, C.L. Clothier and A.S. Hitchcock. Seemingly they were limited to the northern portion of the county.
64

L' Arbre ou le rhizome? Le paysage identitaire dans Pluie et vent sur Télumée miracle de Simone Schwarz-Bart, Délice et le fromager de Xavier Orville et dans Pays mêlé de Maryse Condé

Gustave, Thierry T. January 2009 (has links)
Thesis advisor: Kevin Newmark / This thesis focuses on flora as metaphors and representations of identity in Simone Schwarz-Bart’s Pluie et vent sur Télumée miracle (1972), Xavier Orville’s Délice et le fromager (1977), and Maryse Condé’s Pays mêlé (1985). Within the context of the declining agricultural industry of the seventies and the eighties, these authors represent a new generation of writers from Guadeloupe and Martinique who add their own ambivalent landscape’s visions to those of Aimé Césaire’s Negritude and Édouard Glissant’s Creolization. As flora’s metaphors, trees and rhizomes reveal important aspects of the colonial world. Although the tree is a metaphor to unearth aspects of identity, does it have its own limitations in this colonial world? The theoretical basis for questioning the tree is rooted in Gilles Deleuze, Félix Guattari, and Édouard Glissant's rhizome theories. Chapter one, “Le spectre du paysage tourmenté dans Pluie et vent sur Télumée miracle”, considers the connections of the tormented landscape with the various identities of characters. These identities use flora and characteristics of some trees and plants as rhetorical constructions to highlight different perspectives of the colonial world: race and rebellion and resilience. Chapter two, “Le fromager dans le monde putrescible” in Délice et le fromager, undertakes to understand the meaning of the tree as the narrator. The identity and the nature of the possessed ceiba tree, as the narrator, reveal a corrupted colonial world. As a witness to the main character’s family and the colonial world, this tree provides a unique perspective on the destruction of the family structure and on the corruption of the colonial world. Chapter three, “La thématique du retour à travers l’espace généalogique de Pays mêlé” examines how Maryse Condé’s Pays mêlé challenges the concept of a typical family tree. The family structure through adultery and illegitimacy shows that the fragmented Surena’s genealogy appears to be constructed like a rhizome with multiple wandering links. In this chapter, we will study the questions of origin often revisited within this genealogy and we will analyze the different factors that destabilize and marginalize characters throughout several generations. / Thesis (PhD) — Boston College, 2009. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Romance Languages and Literatures.
65

Diversity and Conservation of Ultramafic Flora in Swaziland

McCallum, Donald Alexander 21 February 2007 (has links)
Student Number : 7729948 - MSc dissertation - School of Animal, Plant and Environmental Sciences - Faculty of Science / As early as 1583 an ultramafic plant was described (Proctor & Woodell, 1975). Since the early 1900s a number of works documenting ultramafic vegetation in various parts of the world have been published (Proctor & Woodell, 1975). The vegetation of the Great Dyke, Zimbabwe was only described in 1965 (Wild, 1965). Much has been written since then, however. It was only as recently as 1989 that any work on ultramafic vegetation in South Africa was published (Morrey et al., 1989), possibly because ultramafic vegetation in the Barberton Greenstone Belt is not noticeably different from that of the surroundings and outcrops are much smaller than the Great Dyke. Studies since then have documented the flora of the ultramafic soils of the Barberton Greenstone Belt (BGB) (Morrey et al., 1992; Williamson, 1994; Balkwill et al., 1997; Williamson et al., 1997; Changwe & Balkwill, 2003; Williamson & Balkwill in prep.). There are around 40 larger outcrops of ultramafic soil in the BGB, the largest of which are shown in Figure 1.1, and to date 29 endemic taxa have been discovered, 5 of which hyperaccumulate Ni (Williamson & Balkwill, in prep). Using IUCN criteria 21 of these taxa have recommended conservation status in the vulnerable categories and four are data deficient. With a number of threatened taxa and scientifically interesting and potentially useful Ni hyperaccumulators on the South African part of the BGB, it was likely that there were additional endemic taxa in Swaziland or additional populations of species collected in South Africa. The ultramafic sites in Swaziland (Figure 1.2) range in altitude from 4750 m above sea level (Figure 1.3) in the south to below 2250 m in the Komati River valley (Figure 1.4), higher than the South African sites which range from 354 – 1648 m above mean sea level (Balkwill et al., 1997). The Swaziland sites thus provide an opportunity to discover the effect of altitude on the vegetation of ultramafic soils in the BGB. The higher sites are cooler than the lowveld sites, with frost at night in winter and even snow on rare occasions. Rainfall averages 127 to 152 mm per year, the highest rainfall being recorded at the higher altitudes, where frequent fog also supplements the rainfall (Compton, 1966). The Swaziland sites also show a range of topography with the lower altitude sites often situated on the slopes of mountains, but higher altitude sites comparatively level. Very little of the ultramafic area in Swaziland has any form of protection and half the area has already been lost to agriculture and forestry. A previous study (Witkowski et al., 2001) identified Kniphofia umbrina Codd. as a critically endangered ultramafic endemic. There was thus an urgent need to study the remaining ultramafic areas and document the vegetation before more of this unique and important habitat is lost, and possibly some endemic plant species too. High population growth, expanding forestry and black wattle encroachment could all impact negatively on the remaining diversity of the ultramafic areas.
66

Um estudo da composição florística de samambaias e licófitas em áreas do semiárido do Brasil

Braga, Nathally Mola Pessoa 26 February 2013 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-02-29T12:56:47Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) PDF - Nathally Mola Pessoa Braga.pdf: 10492664 bytes, checksum: 9430532e37277b0fe4f36bb02279b474 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-03-10T16:54:45Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) PDF - Nathally Mola Pessoa Braga.pdf: 10492664 bytes, checksum: 9430532e37277b0fe4f36bb02279b474 (MD5) / Made available in DSpace on 2016-03-10T16:54:45Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) PDF - Nathally Mola Pessoa Braga.pdf: 10492664 bytes, checksum: 9430532e37277b0fe4f36bb02279b474 (MD5) Previous issue date: 2013-02-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The distribution of organisms and the composition of communities can be explained by the range of dispersal of species or their adaptations to environmental characteristics. Trying to identify which of these factors is most important in determining the composition of the assemblages of ferns and lycophytes in the semiarid region of Brazil, were studied 19 sample areas with approximately 12,000 m² each, located north of Bahia state, in the municipalities of Sento Sé and Sobradinho, in an area known locally as Boqueirão da Onça. In each sampling area were collected species and environmental data were obtained in altitude, soil type and available habitats (terrestrial, epiphytic, rock and water). The Mantel test was used to correlate the floristic composition with the environmental characteristics and the geographical distance between the areas. Were inventoried 26 species, 23 ferns and three lycophyta, gathered in 14 families and 18 genera, with a minimum of one and maximum of seven species for each sample unit. Unlike the geographic distance, environmental factors were related to species similarity between areas, indicating that, on a local scale, the floristic composition and distribution of ferns and lycophytes in semiarid areas of Brazil was related mainly to the environment characteristics, which are adapted species. / A distribuição dos organismos e a composição das comunidades podem ser explicadas pelo alcance de dispersão das espécies ou por suas adaptações às características do ambiente. Buscando identificar qual desses fatores é mais importante para determinar a composição das assembleias de samambaias e licófitas no semiárido do Brasil, foram estudadas 19 áreas amostrais com aproximadamente 12.000 m² cada uma, localizadas ao norte do estado da Bahia, nos municípios de Sento Sé e Sobradinho, em uma região conhecida localmente como Boqueirão da Onça. Em cada área amostral foram coletadas as espécies e foram obtidos os dados ambientais de altitude, tipo de solo e hábitats disponíveis (terrestre, epifítico, rupestre e aquático). O Teste de Mantel foi utilizado para correlacionar a composição florística com as características ambientais e com a distância geográfica entre as áreas. Foram inventariadas 26 espécies, sendo 23 de samambaias e três de licófitas, reunidas em 14 famílias e 18 gêneros, com o mínimo de uma e o máximo de sete espécies para cada unidade amostral. Ao contrário da distância geográfica, os fatores ambientais estiveram relacionados com a similaridade de espécies entre as áreas, indicando que, em uma escala local, a composição florística e a distribuição das samambaias e licófitas em áreas do semiárido do Brasil esteve relacionada, principalmente, com as características do ambiente, as quais as espécies estão adaptadas.
67

Diversidad vegetal del humedal Ciénaga de Zapata, Matanzas, Cuba

Oviedo Prieto, Ramona 15 November 2013 (has links)
La Ciénaga de Zapata es el mayor humedal cubano y uno de los más importantes y mejor conservados de las islas del Caribe. Está cubierto de extensos manglares, herbazales, bosques de ciénaga y vegetación costera. No obstante es una de las zonas menos estudiadas del país, debido fundamentalmente al grado de inaccesibilidad de muchas de sus áreas. Por tal motivo se realizó el diagnóstico del estado actual de la flora vascular del humedal Ciénaga de Zapata, que permitió caracterizar su flora e identificar la situación ambiental del ecosistema. Se realizaron inventarios florísticos, localización y caracterización ambiental del ecosistema durante 38 años, cuantificándose un total de 1370 taxones infragenéricos, 708 géneros y 155 familias. Se reportaron 50 nuevos registros para la flora del territorio. Las familias botánicas más representadas son Poaceae (184) y Leguminosae (115). Predominan las hierbas (47.4%), los arbustos (19), árboles (15) y trepadoras (11). Se listaron 47 especies con categorías de amenazadas, de ellas 21 están protegidas por la Ley Forestal, 80.58% son nativas y 35,7% sinantrópicas. El endemismo resultó en un 11% y las formaciones vegetales más ricas en especies endémicas son Bosque semicaducifolio esclerófilo (54 especies), sabanas sl. (51), bosque semicaducifolio mesófilo (43) y el matorral xeromorfo costero con abundancia de Cactaceae (43). Se identificaron siete especies exóticas invasoras agresivas que más afectan al humedal, además de los incendios forestales y la caza furtiva.
68

Flora acuática y palustre de los humedales interiores sobre arenas cuarcíticas en Pinar del Río

Pérez Hernández, Vidal 03 February 2016 (has links)
No description available.
69

The flora of Leslie Gulch Malheur County, Oregon

Grimes, James W. 01 May 1979 (has links)
A study of the flora of Leslie Gulch Malheur County, Oregon was undertaken to elucidate the relationships of the flora and of the endemic species in the flora, and to determine if these endemic species are restricted to their present distribution by chemical factors of their substrate. A checklist of native plants and a description of the major communities was made and floristic relationships were studied. Chemical and mineralogical tests such as emission spectrography, x-ray diffraction and cation-exchange capacity as well as physical tests such as particle-size distribution and gravimetric water content were performed. The results of the tests gave no indication of any chemical factor which may restrict the distribution of plants. A zeolite, heulandite, is present in 'the ash-tuff which is the substrate for the endemic species Mentzelia packardiae Glad and Senecio ertterae Barkely. However, this would not restrict plant growth. It was concluded that the distribution of the endemics Senecio ertterae Barkley, Mentzelia packardia Glad, Ivesia rhypara Ertter & Reveal, Eriogonum novonudum Peck, and to some extent Astragalus sterilis Barneby and Trifolium owyheense Gilkey is determined primarily by physical factors of their substrates, and that they are pioneer species which may be competitively excluded from normal sites. Artemisia packardiae Grimes & ertter ined. is a species which is restricted by a diminishing relic habitat. The flora of Leslie Gulch has been complicated by interaction of a northern mesic association and a southern xeric association. The endemic species Mentzelia packardiae and Senecio ertterae are recent species which evolved from a southern Great Basin flora which has moved north with the retreat of the last ice sheets. Ivesisa rhypara and artemisia packardiae are recent species which evolved from a northern flora which followed the retreat of the ice sheets north.
70

Tratamiento taxonómico de meliaceae (cabralea, cedrela, guarea, swietenia) en la región de Madidi, Bolivia

Villalobos Huanca, Matha January 2011 (has links)
Este estudio apunta delimitar morfológicamente las especies de Meliaceae presentes en la Región Madidi, ubicada entre los departamentos de La Paz y Beni con alrededor de 94,533 km2 equivalente al 10% del territorio boliviano. Se presenta una clave para diferenciar los géneros y tres claves para identificar las especies tratadas, tanto de material herborizado y de especímenes coleccionados en las expediciones botánicas dentro la Región Madidi. Aportándose para cada especie: sinónimos, descripciones botánicas, comentarios taxonómicos, tipo de hábitat, fenología, nombres comunes, usos, distribución geográfica, ilustraciones y lista de especímenes examinados. Para el análisis multivariable se computaron 135 variables por espécimen: 76 características vegetativas y 59 características reproductivas. A través del programa SPSS se evaluaron tales variables, efectuándose en el siguiente orden: valor medio, desviación estándar, rango y coeficiente de correlación de Spearman, posteriormente el Análisis Discriminante y prueba de medianas Kruskal-Wallis para examinar las variables más significantes en cuanto a la separación entre especies. Se hace referencia a 17 especies pertenecientes a los cinco géneros en revisión, siendo el mejor representado Guarea con siete especies, seguido por Ruagea con cinco, Cedrela con tres, Cabralea y Swietenia con una especie. Como novedad para la Región Madidi se registran por primera vez a Cedrela angustifolia, Guarea glabra, Ruagea pubescens y Ruagea tomentosa, la última especie mencionada llega a ser un nuevo registro para la región como para el país. Los resultados del Análisis Discriminante evidencian que las especies de Cedrela pueden ser determinadas a partir de variables vegetativas, puesto que establecen una separación taxonómica. En cuanto a Guarea se define que las variables vegetativas elegidas no son suficientes para establecer una clara diferenciación entre especies, por contar con amplios rangos de expresión, siendo necesario la inclusión y análisis de variables reproductivas para ayudar a delimitar mejor las especies. Con respecto a Ruagea se establece una separación taxonómica con los valores de las variables vegetativas, la función discriminante resulta estadísticamente significativa entre especies.

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