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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.
51

Optimal site release strategies and impact of biological control agents on spotted knapweed, Centaurea maculosa.

Clark, Sheryl 01 January 2000 (has links) (PDF)
No description available.
52

Pathogenesis of Rocky Mountain spotted fever in Rhesus monkeys following respiratory exposure /

Wolf, George Leopold January 1965 (has links)
No description available.
53

Responses and relationships among Fusarium species, sweet corn, and western spotted cucumber beetles /

Miller, Nathan L. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references. Also available on the World Wide Web.
54

Resistance of selected varieties of cucurbits to the spotted cucumber beetle, Diabrotica undecimpunctata howardi Barber, and the striped cucumber beetle, Acalymma vittata (Fabricius)

Wiseman, Billy Ray. January 1961 (has links)
Call number: LD2668 .T4 1961 W57
55

The Spotted Alfalfa Aphid in Arizona

Tuttle, D. M., Barnes, O. L., Nielson, M. W., Roth, V. D., Schonhorst, M. H. 05 1900 (has links)
No description available.
56

A Study of the Southern Spotted Channel Catfish, Ictalurus Punctatus (Rafinesque)

McClellan, William G. 01 1900 (has links)
The purpose of the present study is to present research data on the propagation of the southern spotted channel catfish.
57

Social play as a tool for developing social-cognitive skills in a wild population of Atlantic spotted dolphins (Stenella frontalis)

Unknown Date (has links)
The purposes of this dissertation were to identify complex social-cognitive behaviors in a population of wild Atlantic spotted dolphins (Stenella frontalis) using long-term video archives and identify developmental trends in those behaviors. Chapter One analyzed calf behavior during foraging events involving maternal teaching in order to identify mechanisms for sharing information between mother and calf... The calves' behavior was affected by the referencing cues, supporting the presence of joint attention and true teaching behavior....Chapter Two observed the altered benthic foraging behavior of juvenile play groups, in which juveniles took turns chasing the fish and using referencing gestures to reference the position of the fish to other individuals during the chase, despite the ability of these young, independent dolphins to catch fish much more quickly and efficiently alson... The third chapter analyzed social object play in which dolphins passed pieces of seaweed between individuals. The data clarified developmental trends in the play, and suggested social-cognitive abilities needed for participation. / by Courtney Elizabeth Bender. / Thesis (Ph.D.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
58

Pesquisa de infecção por rickettsias do grupo da febre maculosa em humanos, cães e eqüídeos e em adultos de Amblyomma cajennense, em área endêmica e não endêmica do estado de São Paulo / Detection of Rickettsia of the Spotted Fever Group in humans, canine, equine and in Amblyomma cajennense adult ticks of an endemic and non endemic área of São Paulo state

Sangioni, Luís Antônio 27 June 2003 (has links)
A febre maculosa, doença de caráter endêmico, já foi diagnosticada em vários estados brasileiros. Em São Paulo a doença é considerada endêmica em algumas regiões e não endêmica ou desconhecida na maior parte do estado. Com o objetivo de estudar a epidemiologia da febre maculosa em regiões consideradas endêmica e não endêmica do estado de São Paulo, foram colhidos carrapatos das pastagens e amostras de sangue de seres humanos, cães e equídeos que viviam em propriedades rurais dos municípios de Pedreiras, (região endêmica); Pirassununga, Sorocaba e Cotia (não endêmica). A colheita de carrapato e de sangue foi efetuada no período de novembro de 2000 a março de 2001, época de predomínio do estágio adulto de ixodideos do gênero Amblyomma na região. Foram colhidos 686 amostras de carrapatos, 50 amostras de sangue de seres humanos, 28 eqüinos, quatro asininos e 16 caninos de região endêmica e 658 amostras de carrapatos, 16 amostras de sangue de seres humanos, 48 eqüinos e cinco caninos de região não endêmica. Os carrapatos foram examinados pelo teste de hemolinfa e pela nested reação em Cadeia da Polimerase (n-PCR). A amplificação de uma região do gene que codifica uma proteína interna de membrana de 17 kDa pela n-PCR, foi utilizada para a detecção do gênero Rickettsia spp nos carrapatos. De um total de 686 amostras de carrapatos de região endêmica, foram encontrados 34 amostras positivas (4,9%) e de 658 amostras de carrapatos de região não endêmica, foram encontrados seis amostras positivas (0,9%). O seqüenciamento de um fragmento de 232 pares de bases do gene 17 kDa efetuados em duas amostras de região endêmica e seis de região não endêmica demonstraram homologia em 100% com a Rickettsia felis. Foi realizada a reação de imunofluorescência indireta (IFI) nos soros sangüíneos utilizando-se antígenos brutos de superfície de Rickettsia rickettsii. Foram considerados positivos soros com títulos superiores a 64. Nenhuma amostra de soro de seres humanos de região endêmica e não endêmica apresentou sorologia positiva. 17 (65,3%) amostras de soros de eqüinos, de região endêmica, apresentaram sorologia positiva, com titulação máxima de 4096. Apenas uma (2,0%) amostra de soro eqüino de região não endêmica apresentou sorologia positiva, com titulação de 128. Cinco (31,2%) amostras de soros de cães de região endêmica apresentaram sorologia positiva, com titulação máxima de 512. Não foi detectada sorologia positiva para cães de região não endêmica. Os títulos elevados da sorologia de cães e eqüinos de região endêmica sugerem indiretamente a circulação de Rickettsia rickettsii nesta localidade. A vigilância epidemiológica em regiões não endêmicas é de grande importância visto que são consideradas vulneráveis a futuros casos de febre maculosa. / Spotted fever, a disease of endemic characteristics, has already been diagnosed in several Brazilian states. The disease is considered to be endemic in some regions of the state of São Paulo and non-endemic or unknown in most of the state. In order to study the epidemiology of spotted fever in endemic and non-endemic regions of the state of São Paulo, ticks were collected from pastures, and blood samples were collected from humans, dogs and horses living in rural properties in the cities of Pedreiras (endemic region); Pirassununga, Sorocaba and Cotia (non-endemic regions). Collection of the ticks was performed from November 2000 to March 2001, a period when adults ticks of the Amblyomma genus predominate in the region. Collection was performed as follows: 686 tick samples, 50 blood samples from humans, 26 blood samples from horses, four blood samples from donkeys and 16 blood samples from dogs in the endemic region. In the non-endemic region, 658 tick samples, 16 blood samples from humans, 48 blood samples from horses and one blood sample from a dog were collected. Ticks were studied using the hemolymph test, and by means of the nested polymerase chain reaction (n-PCR). The amplification, by n-PCR, of a region of the gene that codifies a 17 kDa internal protein in the membrane of the microorganism was used for the detection of the Rickettsia spp genus, in the ticks. From 686 tick samples from the endemic region, 34 were positive (4.9%). From the 658 tick samples collected in the non-endemic region, six were positive (0.9%). Sequencin of a 232 base-pair fragment of the 17 kDa gene, performed in two samples of the endemic region and in six samples of the non-endemic region, showed 100% homology with Rickettsia felis. Indirect immunofluorescence (IFI) was performed in serum samples using crude antigens from Rickettsia rickettsii surface. Serum samples were considered to be positive when presenting titers higher than 64. No human serum sample from the endemic or non-endemic region was positive. Seventeen (65.3%) serum samples from horses in the endemic region were positive, with maximum titer equal to 4096. Only one horse (2,0%) in the non-endemic region presented positive serology, with titer equal to 128. Five (31.2%) dog serum samples from the endemic region were positive, with maximum titer equal to 512. No dog serum sample was positive in the non-endemic region. Epidemiological surveillance in endemic regions is very important, for new spotted fever cases may be expected.
59

Pesquisa de infecção por rickettsias do grupo da febre maculosa em humanos, cães e eqüídeos e em adultos de Amblyomma cajennense, em área endêmica e não endêmica do estado de São Paulo / Detection of Rickettsia of the Spotted Fever Group in humans, canine, equine and in Amblyomma cajennense adult ticks of an endemic and non endemic área of São Paulo state

Luís Antônio Sangioni 27 June 2003 (has links)
A febre maculosa, doença de caráter endêmico, já foi diagnosticada em vários estados brasileiros. Em São Paulo a doença é considerada endêmica em algumas regiões e não endêmica ou desconhecida na maior parte do estado. Com o objetivo de estudar a epidemiologia da febre maculosa em regiões consideradas endêmica e não endêmica do estado de São Paulo, foram colhidos carrapatos das pastagens e amostras de sangue de seres humanos, cães e equídeos que viviam em propriedades rurais dos municípios de Pedreiras, (região endêmica); Pirassununga, Sorocaba e Cotia (não endêmica). A colheita de carrapato e de sangue foi efetuada no período de novembro de 2000 a março de 2001, época de predomínio do estágio adulto de ixodideos do gênero Amblyomma na região. Foram colhidos 686 amostras de carrapatos, 50 amostras de sangue de seres humanos, 28 eqüinos, quatro asininos e 16 caninos de região endêmica e 658 amostras de carrapatos, 16 amostras de sangue de seres humanos, 48 eqüinos e cinco caninos de região não endêmica. Os carrapatos foram examinados pelo teste de hemolinfa e pela nested reação em Cadeia da Polimerase (n-PCR). A amplificação de uma região do gene que codifica uma proteína interna de membrana de 17 kDa pela n-PCR, foi utilizada para a detecção do gênero Rickettsia spp nos carrapatos. De um total de 686 amostras de carrapatos de região endêmica, foram encontrados 34 amostras positivas (4,9%) e de 658 amostras de carrapatos de região não endêmica, foram encontrados seis amostras positivas (0,9%). O seqüenciamento de um fragmento de 232 pares de bases do gene 17 kDa efetuados em duas amostras de região endêmica e seis de região não endêmica demonstraram homologia em 100% com a Rickettsia felis. Foi realizada a reação de imunofluorescência indireta (IFI) nos soros sangüíneos utilizando-se antígenos brutos de superfície de Rickettsia rickettsii. Foram considerados positivos soros com títulos superiores a 64. Nenhuma amostra de soro de seres humanos de região endêmica e não endêmica apresentou sorologia positiva. 17 (65,3%) amostras de soros de eqüinos, de região endêmica, apresentaram sorologia positiva, com titulação máxima de 4096. Apenas uma (2,0%) amostra de soro eqüino de região não endêmica apresentou sorologia positiva, com titulação de 128. Cinco (31,2%) amostras de soros de cães de região endêmica apresentaram sorologia positiva, com titulação máxima de 512. Não foi detectada sorologia positiva para cães de região não endêmica. Os títulos elevados da sorologia de cães e eqüinos de região endêmica sugerem indiretamente a circulação de Rickettsia rickettsii nesta localidade. A vigilância epidemiológica em regiões não endêmicas é de grande importância visto que são consideradas vulneráveis a futuros casos de febre maculosa. / Spotted fever, a disease of endemic characteristics, has already been diagnosed in several Brazilian states. The disease is considered to be endemic in some regions of the state of São Paulo and non-endemic or unknown in most of the state. In order to study the epidemiology of spotted fever in endemic and non-endemic regions of the state of São Paulo, ticks were collected from pastures, and blood samples were collected from humans, dogs and horses living in rural properties in the cities of Pedreiras (endemic region); Pirassununga, Sorocaba and Cotia (non-endemic regions). Collection of the ticks was performed from November 2000 to March 2001, a period when adults ticks of the Amblyomma genus predominate in the region. Collection was performed as follows: 686 tick samples, 50 blood samples from humans, 26 blood samples from horses, four blood samples from donkeys and 16 blood samples from dogs in the endemic region. In the non-endemic region, 658 tick samples, 16 blood samples from humans, 48 blood samples from horses and one blood sample from a dog were collected. Ticks were studied using the hemolymph test, and by means of the nested polymerase chain reaction (n-PCR). The amplification, by n-PCR, of a region of the gene that codifies a 17 kDa internal protein in the membrane of the microorganism was used for the detection of the Rickettsia spp genus, in the ticks. From 686 tick samples from the endemic region, 34 were positive (4.9%). From the 658 tick samples collected in the non-endemic region, six were positive (0.9%). Sequencin of a 232 base-pair fragment of the 17 kDa gene, performed in two samples of the endemic region and in six samples of the non-endemic region, showed 100% homology with Rickettsia felis. Indirect immunofluorescence (IFI) was performed in serum samples using crude antigens from Rickettsia rickettsii surface. Serum samples were considered to be positive when presenting titers higher than 64. No human serum sample from the endemic or non-endemic region was positive. Seventeen (65.3%) serum samples from horses in the endemic region were positive, with maximum titer equal to 4096. Only one horse (2,0%) in the non-endemic region presented positive serology, with titer equal to 128. Five (31.2%) dog serum samples from the endemic region were positive, with maximum titer equal to 512. No dog serum sample was positive in the non-endemic region. Epidemiological surveillance in endemic regions is very important, for new spotted fever cases may be expected.
60

Spatial Structure and Population Genetic Variation in a Eucalypt Species Complex

King, Rachel, n/a January 2004 (has links)
In this study, the relative influences of selection, gene flow, and other evolutionary forces on the spatial structure of genetic variation within a eucalypt species complex (the spotted gums: genus Corymbia, section Politaria) were assessed. The study investigated the spatial genetic structure among four putative species of spotted gum (broad-scale), as well as within a single population (fine-scale)of one species, using both molecular and quantitative markers. The spotted gum complex occurs naturally across a range of 2500 km in eastern Australia. Spatial genetic variation within and between the four putative spotted gum species was examined using both chloroplast and nuclear markers. No significant differentiation was found between the three northern species of the complex, C. citriodora, C. variegata and C. henryi. The southern species, C. maculata, shared no haplotypes with any of the three northern species. These results disagree in part with those reported in a previous allozyme based study in which C. henryi was found to be significantly divergent from C. variegata (with which it is sympatric) and more closely aligned with C. maculata. Re-analysis of the allozyme data provided evidence of selection acting at the PGM2 locus within populations of C. variegata and C. henryi. The exclusion of this locus from the data set led to concordance between the cpDNA and nDNA analyses. Restricted gene flow and evidence of isolation by distance were identified as the dominant processes influencing the contemporary distribution of the cpDNA haplotypes. No geographic structure of haplotypes was found and complex genealogical relationships between haplotypes indicated the combined effects of past fragmentation, range expansion and possible long distance dispersal events. The variation and spatial structure in both neutral molecular markers and quantitative genetic traits were compared to explore the relative influences of dispersal and selection within a single eucalypt population. Both mature trees (n=130) from a natural population of C. variegata and their progeny (n=127) were sampled. A very high outcrossing rate (98%) was estimated for the population based on data from seven microsatellite loci. This suggested regular pollen–mediated gene flow into the population, further supported by the observed high levels of genetic diversity and polymorphism. Significant positive spatial structure was found between parent trees occurring up to 150 m apart in the natural forest, although genetic distance between these individuals suggested limited relatedness (i.e. less than half-sib relatedness). The effect of pollen-mediated gene flow appears, therefore, to swamp any effect of nearest neighbour inbreeding which has been reported in other studies of eucalypt populations and has been attributed to limited seed dispersal. Resistance to the fungal disease Sporothrix pitereka (Ramularia Shoot Blight) was measured on progeny from each of the population study trees. Substantial resistance variability was found, along with a high estimate in heritability of resistance (0.44 ± 0.06), indicating significant additive genetic variation within the population. Spatial analysis showed no significant spatial structure with resistant and susceptible genotypes apparently distributed randomly throughout the population. The lack of concordance between the molecular and quantitative markers suggests that there may be a cost to resistance. Temporal variation in the severity of disease outbreaks may have then led to differential selection of seedlings across many generations, maintaining variability in disease resistance and facilitating the apparent random distribution of disease resistant and susceptible genotypes throughout the population. C. variegata is an important commercial forestry species. The identification of strong genetic control in the disease resistance trait, as well as significant adverse genetic and phenotypic correlations between susceptibility and growth traits, will aid future breeding programs. Controlled crosses between resistant genotypes from this population should result in strong genetic gains in both resistance and growth, with little costs associated with inbreeding depression due to the highly outcrossed nature of the population.

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