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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.
101

The Effects of Simulated Altitude on the Intestinal Flora of Guinea Pigs

Funderburk, Noel R. 05 1900 (has links)
The purpose of this paper is to report the results of studies on the aerobic, mesophilic intestinal flora of guinea pigs subjected to conditions similar to those encountered by man in spacecraft.
102

Frutanos de Vernonia herbacea (Vell.) Rusby : variações em função da temperatura e da disponibilidade de agua

Tagliacozzo, Glaucia Moraes Dias 23 June 1995 (has links)
Orientador: Sonia Machado de Campos Dietrich / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-20T12:50:46Z (GMT). No. of bitstreams: 1 Tagliacozzo_GlauciaMoraesDias_D.pdf: 4066252 bytes, checksum: 12d3310b20a4eea98a3e5994cc946039 (MD5) Previous issue date: 1995 / Resumo: Os objetivos deste trabalho foram verificar o efeito de temperatura baixa e do déficit hídrico no conteúdo e na composição dos frutanos presentes em rizóforos de Vernonia herbacea, e determinar se a inulina isolada e purificada de V. herbácea pode ser usada para avaliar o rítmo de filtração glomerular em substituição à inulina importada. Plantas intactas em início de dormência, que apresentavam parte aérea, ao final do tratamento de frio (5°C) apresentaram conteúdo de frutanos maior que o das plantas mantidas a 25°C. Tratamento semelhante com plantas sem a parte aérea (dormência), apresentaram poucas diferenças no conteúdo de frutanos dos rizóforos das plantas mantidas a 5 ou 25°C. Esse resultado sugere que o acúmulo de frutanos ocorreu devido ao excesso de fotoassimilados provenientes da parte aérea e que o frio não tem efeito direto neste acúmulo. Fragmentos de rizóforos retirados de plantas em fase de dormência, apresentaram ao final do experimento um aumento no conteúdo de polifrutanos em relação ao início do tratamento. No entanto, fragmentos retirados de plantas em fase de brotação apresentaram uma diminuição do conteúdo de polifrutanos ao longo do período de tratamento. Esse aumento ou diminuição ocorreram independentemente da temperatura, mostrando que as variações observadas parecem estar mais relacionadas com o estádio fenólogico da planta do que com o tratamento de temperatura. O conteúdo relativo de água nos tecidos (CRA) dos rizóforos de plantas submetidas a déficit hídrico declinou mais lentamente que o conteúdo de água no solo. Até 30 dias sem irrigação o CRA se manteve igual ao do início do tratamento (100%), apesar do conteúdo de água no solo haver baixado para 36 %. Essas plantas foram as que apresentaram em seus rizóforos os maiores valores de oligofrutanos acompanhados pelas maiores quantidades de sacarose e frutose livre. Concluiu-se que em V. herbacea os frutanos estão associados ao mecanismo de manutenção de turgor dos tecidos dos rizóforos, através de alterações nos tamanhos de suas moléculas. Nos experimentos sobre o uso da inulina de V. herbacea na função renal verificou-se que a carga filtrada e a carga excretada da inulina foram iguais, e que o ritmo de filtração glomerular foi o mesmo da inulina comercial, indicando que esta substância pode ser usada para medir adequadamente a filtração glomerular / Doutorado / Doutor em Ciências Biológicas
103

Sobre a interação de formigas com pequi do cerrado, Caryocar Brasiliense Camb. (Caryocaraceae) : o significado ecologico de nectarios extraflorais

Oliveira, Paulo Sergio Moreira Carvalho de, 1957- 19 July 2018 (has links)
Orientador : Woodruff W. Benson / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-19T02:01:56Z (GMT). No. of bitstreams: 1 Oliveira_PauloSergioMoreiraCarvalhode_D.pdf: 7424619 bytes, checksum: 2b89b7b5fb9c19606612e3ce0812b507 (MD5) Previous issue date: 1988 / Resumo: Caryocar brasliense possui nectários extraflorais (NEFs) na face externa das sépalas de seus botões florais, os quais são intensamente visitados por diversas espécies de formigas. Este estudo Investigou a interação de formigas com Caryocar, em vegetação de cerrado, rio município de Itirapina-SP. Foi registrado um total de 34 espécies (17 gêneros) de formigas visitantes de Caryocar, em Itiraplna. Tanto em número de espécies, como em número de indivíduos registrados, formigas Camponotus foram as melhor representadas nos censos realizados sobre Caryocar. Formigas dos gêneros Zacryptocerus, Azteca e Pheldole também foram comumente observadas visitando NEFs de Caryocar. Camponotus crassus, C. aff. blandus e Zacryptocerus pusllus foram as formigas mais abundantes durante o dia, enquanto que Camponotus rufipes, C.rengerl e Pheldole sp. foram as mais abundantes durante a noite. O número de plantas de Caryocar sendo visitadas por formigas foi significativamente maior que o de espécies sem NEFs. Como conseqüência disto, o número de iscas (cupins vivos) atacadas por formigas também foi maior em Caryocar que em plantas sem NEFs. Formigas forragearam preferencialmente sobre botões de Caryocar, atacando um número significativamente maior de cupins nesta região da planta do que em folhas jovens ou adultas. ...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Caryocar brasliense bears extrafloral nectaries (EFNs) on the outer surface of the sepals of its buds, which are intensively visited by several ant species. This study investigated the interaction between ants and Caryocar in an area of cerrado vegetation near Itirapina-SP. A total of 34 ant species (17 genera) were recorded visiting Caryocar at Itirapina. Both in number of species and individuals Camponotus ants were the most representatives in ant censuses conducted on Caryocar. Other ant genera such as Zacryptocerus, Azteca and Pheidole were also commonly observed on the EFNs of Caryocar. Câmponotus crassus, C. aff. blandus and Zacryptocerus pusillus were the most abundant diurnal ants, while Camponotus rufipes, C. rangeri 1 and Pheidole sp. I were the most abundant nocturnal ones. The number of Caryocar plants belng visited by ants was significantly greater than that of non-nectariferous plants, resulting in many more termite-baits being attacked by ants on Caryocar than on plants without EFNs. Ants foraged more intensively on the buds of Caryocar, where a greater number of termites were attacked, as compared with young or mature leaves. ...Note: The complete abstract is available with the full electronic digital thesis or dissertations / Doutorado / Ecologia / Doutor em Ciências Biológicas
104

A Yearly Study of the Bacterial Flora of Lake Dallas Water with Special Reference to Sanitation

Foster, Edwin Michael 06 1900 (has links)
The purpose of this thesis is to determine the relative numbers of colon bacteria in the water of Lake Dallas.
105

Studies on the Bacterial Flora of Milk, Ice Cream, and Beverages in Denton, Texas

Smith, William Russell 08 1900 (has links)
The purpose of this study is to observe the frequency of occurrance of members of the colon group in various brands of milk, milk products, and soft drinks marketed in the city of Denton, and to determine the total number of bacterial organisms occuring in these products from week to week.
106

Figuring the heroine in the ankara romance series against the archetype of Flora Nwapa’s efuru: marriage, procreation, love, sex, and work, master’s

Mundembe, Enet January 2021 (has links)
Doctor Educationis / Romantic love has been neglected in the study of African literature and culture. It has been misconstrued and overlooked in canonical African literature, and the scholarship of that literature. Only recently has some attention been directed to African popular romance writing. The main focus of African literature and its scholarship fell on questions of history, colonial resistance, and, later, in the work of women writers, on gender oppression. This neglect is gradually being addressed. Romantic love is slowly getting more recognition than before in the study of African literature, and as evidenced in popular culture by recent African imprints like the South African-based Sapphire imprint, and Nollybooks and Okada Books in Nigeria, among others. The Ankara popular romances under study in this thesis focus on the concerns of contemporary African women and suggest resolutions to their problems. Although they are in some ways similar to Anglo-American romance fiction like Mills and Boon and Harlequin, they present some concerns specific to their context. Among these are questions of childbearing, locally relevant questions related to work and career, and contextually shaped issues around desire and the erotic. The contemporary Ankara novellas have been read against the backdrop of Flora Nwapa’s novel Efuru, a first-generation African novel written by the first published African woman writer. We see that the dilemmas encountered by the Ankara heroines represent the concerns of Efuru, Nwapa’s heroine, with some variation in some cases. Of the Ankara novellas published to date, the following titles will be studied, namely, A Tailor-Made Romance by Oyindamola Affinih, Love Me Unconditionally by Ola Awonubi, A Taste of Love by Sifa Asani Gowon, The Elevator Kiss by Amina Thula, Finding Love Again by Chioma Iwunze-Ibiam and Love’s Persuasion also by Ola Awonubi. The thesis establishes that the resolution of the Ankara novellas is different from the ending of Efuru. Nwapa leaves Efuru’s dilemmas unresolved, whereas the Ankara novellas, because they are romances, present idealised resolutions in which model heroes, who manifest transformations coming to being in society more generally, constitute the wished-for happy-ever-after ending.
107

Macroinvertebrate communities associated with selected macrophytes in Lake Onalaska : effects of plant type, predation, and selective feeding /

Chilton, Earl Wallace January 1986 (has links)
No description available.
108

A Mesozoic Fossil Flora from Arctic Ellesmere Island

Davies, Pamela 10 1900 (has links)
Macrofossils from a Mesozoic fossil flora from Ellesmere Island, North West Territories are described and their affinities discussed, Several rarely occurring genera and species ore discussed in detail. The deposit in which they occur is dated using the known ranges of identified macro fossils and miospores, rand the results compared with those of other workers. The described flora is compared with floras of similar age in other parts of the world. / Thesis / Master of Science (MS)
109

The Affects of Explosively and Electrically Generated Hydrodynamic Shock Waves on the Bacterial Flora of Beef and Poultry

Lorca, Tatiana Andrea 19 August 2002 (has links)
The affects of hydrodynamic shock wave treatment on the bacterial flora of raw beef and poultry were evaluated. Hydrodynamic shock waves were generated in an aqueous treatment medium by either the detonation of two types of explosive charges (explosively-generated hydrodynamic shock waves [EHSW]) (a binary or a molecular explosive) or by electrical discharge (high voltage arc discharge Hydrodyne (TM [HVADH; Hydrodyne, Inc.]). A variety of sample types (whole steaks, ground beef, a water and ground beef slurry) were used to determine the lethality affects of EHSW on cells of the marker microorganism Listeria innocua suspended in a simple broth medium. These sample types were used in order to evaluate the affects of the process not only on the surface, but throughout the bulk of the samples in order to determine whether EHSW could also be used as a non-thermal alternative to reduce the bacterial flora of non-intact or ground meats. The levels of psychrotrophic, lactic, and coliform populations on the surface of whole eye of round steaks submitted to EHSW processing did not differ (P> 0.05) from those of untreated whole eye of round steaks. Parameters expected to influence the nature, magnitude, and propagation of the hydrodynamic shock wave were also varied and evaluated in order to determine which individual parameter or combination of parameters affected the bactericidal potential of EHSW or HVADH processing. Treatment with EHSW failed (P > 0.05) to produce lethality effects on the psychrotrophic, lactic, and coliform populations of ground beef, regardless of the composition and mass of explosive used, the number of successive EHSW treatments used, the relative distance between the explosive charge and the top surface of the sample, or the temperature of the water used in the treatment chamber. EHSW processing did not change (P >0.05) the bacterial population of treated ground beef samples when compared to untreated controls during a five day refrigerated storage study. No lethality effects were observed (P >0.05) in ground beef samples treated by HVADH when samples were subjected to one, two, or three successive HVADH treatments. Minimal penetration of surface inoculated bacteria was observed for both beef steaks and boneless skinless chicken breasts subjected to EHSW and HVADH, respectively. In EHSW-treated beef eye of round steaks, marker bacteria were detected within the first 300 um of tissue below the inoculated surface, 50-100 um beyond the depth of untreated surface inoculated steaks. In HVADH-treated boneless skinless chicken breasts, marker bacteria were detected within the first 200 um below the inoculated surface, 50-100 um beyond the depth of untreated surface inoculated boneless skinless chicken breasts. This suggests that although no difference in the bacteriological populations was observed between EHSW treated, HVADH treated, and untreated control samples of whole steaks (and ground beef treated with both HVADH and EHSW), HVADH and EHSW treatments affect the movement of surface bacteria. United States Department of Agriculture (USDA) guidelines suggest intact beef steaks be cooked to achieve a cooked color appearance on the surface and raw poultry be cooked to an internal temperature of 77° C to inactivate the pathogens Escherichia coli O157:H7 and salmonellae which are of concern in beef and poultry, respectively. By following these guidelines during proper cooking, consumers achieve thermal inactivation of these pathogens. Since the movement of the marker bacterium observed in treated steaks and boneless skinless chicken breasts was minimal, proper cooking of the products would be expected to inactivate vegetative bacterial cells at this depth. Therefore, EHSW and HVADH treated whole beef steaks and boneless skinless chicken breasts would not be expected to pose a bacterial hazard if the products were properly cooked. / Ph. D.
110

The lichen flora of Hull, with particular reference to zonal distribution and environmental monitoring

Seaward, Mark R.D. January 2004 (has links)
Yes / The role of lichens as environmental monitors is widely recognised. Not only are they valuable as indicators of habitat stability and enyironmental continuity, but they are also effectiye in monitoring environmental quality. more particularly air and soil (and more recently water) pollution. In the past. the main role of lichens in this context has been to monitor sulphur dioxide air pollution. especially stable and rising levels (Seaward 1993). Howeyer, it has also been shown that lichens arc effective monitors of falling levels of gaseous sulphur dioxide and indeed of other pollutants. some of which are manifesting themselves as a consequence of the reduction in the former; of particular interest in this respect is the use of lichens to detect and determine the extent of qualitative changes in air pollution such as the impact of acid rain and hypertrophication (Seaward 1997: Seaward & Coppins 2(04).

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