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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.
1

Meio ambiente e estatura humana: a sazonalidade da duração efetiva do dia como resposta para a variação clinal observada no Brasil / Environment and human stature: the seasonality of the effective day length as a response to the clinal variation observed in Brazil

Rosseti, William 25 April 2019 (has links)
A associação entre latitude e o tamanho corporal dos seres vivos é um fenômeno discutido por muitos pesquisadores. Foi observado que os corpos tendem a ser maiores em locais mais distantes do Equador e a temperatura ambiental já foi considerada a causa principal desse aumento corporal. O objetivo geral deste trabalho é verificar a relação entre altura e variáveis climáticas no Brasil, seguido dos objetivos específicos: i) construir cartogramas representativos das variáveis climáticas no Brasil; ii) verificar a existência de relação entre altura e latitude na população brasileira; iii) determinar, utilizando métodos estatísticos, quais elementos climáticos influenciam no crescimento das pessoas e iv) discutir a influência da sazonalidade dos elementos climáticos nas respostas fisiológicas do organismo humano. Para contemplar os objetivos colocados, este trabalho utilizou dados antropométricos, geográficos e climáticos previamente publicados por institutos de pesquisa brasileiros para investigar a existência e possíveis causas da correlação entre latitude e estatura de adolescentes de 12 anos de idade do sexo feminino e 14 anos de idade do sexo masculino. A variação latitudinal é seguida pela variação de diversos elementos climáticos, os aqui estudados foram: temperatura, insolação, radiação solar global e duração efetiva do dia. Os modelos matemáticos e de regressão linear múltipla mostram que o peso corporal juntamente a alguma variável climática são os melhores estimadores da estatura nas idades analisadas e a duração efetiva do dia acima de determinada intensidade luminosa é a variável climática que mais vezes mostrou-se estatisticamente relevante. Uma resposta para a existência da variação clinal na estatura dos seres humanos pode estar relacionada com a influência ambiental, que é dada em função da localização geográfica e da sazonalidade sobre a fisiologia humana. / The association between latitude and body size of living beings is a phenomenon discussed by many researchers. It was observed that the bodies tend to be larger in places more distant from the Equator and the environmental temperature has already been considered the main cause of this corporal increase. The general objective of this work is to verify the relationship between height and climatic variables in Brazil, followed by the specific objectives: i) to construct cartograms representative of climatic variables in Brazil; ii) verify the existence of a relationship between height and latitude in the Brazilian population; iii) determine, using statistical methods, which climatic elements influence the growth of people, and iv) discuss the seasonal influence of climatic elements on the physiological responses of the human organism. In order to contemplate the objectives, this work used anthropometric, geographic and climatic data previously published by Brazilian research institutes to investigate the existence and possible causes of the correlation between latitude and height of 12-year-old female and 14-year-old adolescents male. The latitudinal variation is followed by the variation of several climatic elements, the ones studied here were: temperature, insolation, global solar radiation and effective day length. The mathematical and multiple linear regression models show that body weight together with some climatic variable are the best height estimators in the analyzed ages and the effective day length above a determined luminous intensity is the climatic variable that has shown to be statistically more relevant . An answer for the existence of clinal variation in human stature may be related to environmental influence, which is given by geographic location and seasonality on human physiology
2

A Comparison of Academic Achievement of Boys and Girls from Full-Day and Half-Day Kindergartens

Tabb, Juanita K. (Juanita Kay) 12 1900 (has links)
The purpose of this study was to determine whether any differences in academic achievement existed between full-day and half-day kindergarten students at the end of their kindergarten and first-grade school years. Two public schools considered comparable in size, philosophy, and socioeconomic levels of a large school district in Texas participated in the study. One of the schools provided a full-day kindergarten program; the other school provided a half-day kindergarten program. Kindergarten students from each of the two schools were match-paired according to birthday and sex. The total sample size was fifty students. All students were tested in December, 1985, with the Metropolitan Achievement Test. Preprimer Level, and in May, 1986, the end of the kindergarten year, with the Primer Level of the Metropolitan Achievement Test. The Metropolitan Achievement Test. Primary I Level, was additionally administered to the subjects in April, 1987, at the end of their first-grade school year. During each testing period, the subjects were administered the Reading, Language, and Math subtests of the Metropolitan Achievement Test. The following supplemental data also were gathered on the students: The Metropolitan Readiness Test II scores and the TEAMS test scores. The data obtained from the testing batteries were statistically analyzed using the .05 level of significance to test each hypothesis. In analyzing the data of all of the academic achievement testing batteries, statistical conclusions revealed that there was no significant difference in the mean scores of children (boys or girls) attending the fullday kindergarten program and children attending the half-day kindergarten program in academic achievement at the end of the kindergarten year or at the end of the first-grade year. It is recommended that continued studies be conducted to investigate the academic achievement of students attending full-day and half-day kindergarten programs. It is also recommended that other variables rather than academic achievement be studied to determine their effects on full-day and half-day kindergarten students.
3

Atividade cambial em ramos de Kielmeyera grandiflora (WAWRA) saddi (Callophylaceae) ocorrentes no cerrado paulista / Cambial activity in branches of Kielmeyera grandiflora (WAWRA) saddi (Callophylaceae) in cerrado of São Paulo

Parmeggiani, Rafaela Prosdocini [UNESP] 16 December 2015 (has links)
Submitted by Rafaela Prosdocini Parmeggiani (rafaela.prosdocini@gmail.com) on 2016-02-16T16:01:51Z No. of bitstreams: 1 Atividade cambial em ramos de Kielmeyera grandiflora (Wawra) Saddi (Calophyllaceae) ocorrentes no cerrado paulista.pdf: 2086514 bytes, checksum: d4efa2e5aa9b442218c364e59bc53a9a (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-02-17T15:53:14Z (GMT) No. of bitstreams: 1 parmeggiani_rp_me_bot.pdf: 2086514 bytes, checksum: d4efa2e5aa9b442218c364e59bc53a9a (MD5) / Made available in DSpace on 2016-02-17T15:53:14Z (GMT). No. of bitstreams: 1 parmeggiani_rp_me_bot.pdf: 2086514 bytes, checksum: d4efa2e5aa9b442218c364e59bc53a9a (MD5) Previous issue date: 2015-12-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / No cerrado, as estações são bem demarcadas pela sazonalidade pluvial, portanto, espera-se que haja uma sazonalidade na atividade do câmbio vascular. Kielmeyera grandiflora é considerada uma espécie modelo para estudos de atividade cambial em ramos, pois possui módulos de crescimento bem demarcados, formados por cicatrizes da gema terminal. Nosso objetivo foi de entender qual a relação entre a atividade cambial de Kielmeyera grandiflora (Wawra) Saddi (Calophyllaceae), os fatores ambientais e a fenologia e responder se a atividade cambial varia entre três módulos de crescimentos consecutivos. A área de estudo é um fragmento de cerrado em regeneração no município de Botucatu, estado de São Paulo, Brasil (S 22º53’11.0’’, W 48º29’17.3’’). Foram amostrados mensalmente os três últimos módulos de crescimento dos ramos de três indivíduos durante o período de fevereiro de 2012 a fevereiro de 2013. No mesmo período, a fenologia (brotação, folhas novas, folhas adultas, folhas senescentes e queda foliar) foram avaliadas. O material foi fixado em CRAF III para conservação do conteúdo celular. As amostras foram desidratadas em série alcoólica e incluídas em resina metacrilato para posterior corte em micrótomo rotativo. As análises foram feitas em fotomicroscópio de luz. Utilizamos Modelo Generalizado Linear Misto (GLMM) com erro Binomial para a variável resposta presença/ausência da atividade cambial e erro de Poisson para a variável resposta de contagem de paredes recém formadas. O início da atividade cambial, a brotação e o desenvolvimento de folhas novas ocorreram durante o mês de agosto no período seco. O período de atividade cambial sobrepôs-se à estação chuvosa, temperaturas elevadas e comprimento do dia entre 12 e 13,6 h. O câmbio vascular entrou em dormência em maio, mês que ainda chovia, contudo a temperatura e o comprimento do dia passavam por quedas acentuadas. A variação da atividade cambial entre os módulos de crescimento foi representativa somente no período de reativação cambial, mostrando que o módulo 1, mais próximo às fontes de auxina, apesar de ter iniciado atividade junto ao módulo 3, produziu em todo o período analisado, maior quantidade de células novas, possivelmente devido à ação de hormônios produzidos nos tecidos jovens e em desenvolvimento. / In the cerrado, the seasons are well marked by rain seasonality; therefore, there is a seasonality in the vascular cambium activity. Kielmeyera grandiflora is considered a model for branch cambial activity studies because it has well marked growth modules formed by terminal bud scars. Our goal was to understand what the relationship between cambial activity of Kielmeyera grandiflora (Wawra) Saddi (Calophyllaceae), environmental factors and the phenology and answear wheter cambial activity varies between three consecutive sections of internodal growth. The study area is a cerrado fragment in regeneration in the city of Botucatu, São Paulo State, Brazil (22° 53 ' S 11.0 '', W 48° 29 ' 17.3 ''). Were sampled on a monthly basis the last three modules of growth of branches of three individuals during the period between February 2012 to February 2013. The material was fixed in CRAF III for preservation of cell content. The samples were dehydrated in alcohol series and included in historesin for further cut in rotary microtome. Analyses were made on light microscope. We used Generalized Linear Mixed Model (GLMM) with Binomial error for the variable reply presence/absence of cambial activity and Poisson error for the variable count response of newly formed walls. The beginning of cambial activity, the sprouting and the development of new leaves occurred during the month of August in the dry period. The period of cambial activity overlapped the rainy season, high temperatures and day length between 12 and 13, 6 h. The vascular cambium dormancy was observed in May, a raining month; however, temperature and day length was decreasing. The variation of cambial activity between the internodal growth sections was representative just in reactivation period, showing that the younger internodal section, closest to the sources of auxin, has produced in the whole study period a larger number of new cells that the older, possibly due to the action of hormones produced in young and development tissues.
4

FENOLOGIA REPRODUTIVA DE Prunus myrtifolia (L.) Urb. E Casearia sylvestris Sw EM CLIMA SUBTROPICAL NO SUL DO BRASIL / REPRODUCTIVE PHENOLOGY OF Prunus myrtifolia (L.) Urb. and Casearia sylvestris Sw IN SUBTROPICAL CLIMATE IN SOUTHERN BRAZIL

Pissatto, Mônica 19 August 2016 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The rhythm of flowering, fruiting, flushing and leaf fall is characteristic of each species and varies depending on weather conditions. Among the meteorological factors of greater influence on plant phenology are the air temperature, the day length and water variations. The phenological study provides basic information for management and conservation of the species and makes it possible to understand the relationship between the growth and development of plants and meteorological factors. The objectives of this study were to characterize the reproductive phenological pattern of a population of Prunus myrtifolia (L.) Urb. and a population of Casearia sylvestris Sw in Santa Maria, Rio Grande do Sul and the relationship of the reproductive phenophases with the air temperature and the day length annual variation. Phenological observations were carried out fortnightly in 10 plants of each species, selected randomly, located in the Botanical Garden of the Federal University of Santa Maria (UFSM), (29º42'S; 53º42'W; 90). The period of the study was from July 2013 to December 2015 to C. sylvestris and from August 2010 to September 2014 for P. myrtifolia. The phenofases observed were flower buds, anthesis, unripe fruits and ripe fruits. The characterization of reproductive phenology pattern of the populations was performed using the phonological Indexes of Fournier and Activity. For both species were analyzed the relation between the annual variation of the phenological indexes with the meteorological factors. In addition was performed analysis of heat sum, photothermal units and variation of flowering day length to find which of these factors is determinant of flowering induction in this species. The main episode of flowering for P. myrtifolia occurred from July to November with greater intensity and activity from August to October. Fruiting occurred from September to February, with greater levels of activity and intensity of unripe fruits from October to December and of ripe fruit from December to January. The flowering time of the population of C. sylvestris was from June to November. The flower buds showed sharp increase in the levels of intensity and activity during the transition from July to August, occurring its greatest expression in August and September. Anthesis was observed from July to October, with pronunced and abrupt increase in the levels of intensity and activity during the transition from August to September, with its greater expression in mid-September for all the years observed. The fruits occurred mainly in October and November, both unripe and ripe. Species showed seasonal phenological pattern with annual flowering and fruiting. The results showed that the increase in day length which starts after the winter solstice is crucial in flowering induction for this species. The astronomical factor proved to be a more reliable predictor of the flowering initiation date than the heat sum and the photothermal units. In both cases fructification occurred in the period of the year with higher air temperatures and longer days. Therefore, the photoperiodic response of the plants ensures that the fruiting takes place in a period with great availability of energy. / O ritmo de floração, frutificação, brotamento e queda de folhas é característico de cada espécie e varia em função das condições meteorológicas. Dentre os fatores meteorológicos de maior influência na fenologia vegetal estão a duração astronômica do dia, a temperatura do ar e as variações hídricas. O estudo fenológico gera informações básicas para o manejo e conservação das espécies e possibilita compreender a relação entre o crescimento e o desenvolvimento das plantas associados aos fatores meteorológicos. Os objetivos deste trabalho foram caracterizar o padrão fenológico reprodutivo de uma população de Prunus myrtifolia (L.) Urb. e de uma população de Casearia sylvestris Sw em Santa Maria, Rio Grande do Sul e a relação das fenofases reprodutivas com a duração astronômica do dia e a temperatura do ar. As observações fenológicas foram realizadas quinzenalmente em 10 indivíduos de cada espécie, selecionados aleatoriamente, localizados no Jardim Botânico da Universidade Federal de Santa Maria (UFSM), (29º42 S; 53º42 W; 90). O período analisado foi de julho de 2013 a dezembro de 2015, para C. sylvestris e de agosto de 2010 a setembro de 2014 para P. myrtifolia. As fenofases observadas foram botões florais, antese, frutos novos e frutos maduros. A caracterização do padrão fenológico reprodutivo das populações foi realizado utilizando-se os Índices de Fournier e de Atividade. Para ambas as espécies foi relacionada a variação anual dos índices fenológicos com os dados meteorológicos do período. Além disso, foi realizada análise de soma térmica, unidades fototérmicas e de variação da duração astronômica do dia de floração para verificar qual desses fatores é determinante para a indução da floração das espécies. Para P. myrtifolia o episódio principal de floração ocorreu de julho a novembro com maior intensidade e atividade de agosto a outubro. A frutificação ocorreu de setembro a fevereiro, com maior atividade e intensidade de frutos novos de outubro a dezembro e de frutos maduros de dezembro a janeiro. A época de floração da população de C. sylvestris foi de junho a novembro. Os botões florais apresentaram aumento pronunciado da intensidade da atividade sempre durante a transição do mês de julho para o mês de agosto, ocorrendo sua maior expressão em agosto e setembro. A antese foi observada de julho a outubro, com aumento pronunciado e abrupto da intensidade e da atividade durante a transição do mês de agosto para o mês de setembro, com o pico de expressão em meados de setembro, para todos os anos observados. Os frutos novos e maduros ocorreram principalmente em outubro e novembro. Ambas as espécies apresentaram padrão fenológico sazonal, com floração e frutificação anual. Os resultados demonstraram que o aumento da duração astronômica do dia que inicia após o solstício de inverno é determinante na indução da floração das espécies. O fator astronômico demonstrou ser um preditor mais confiável para a data de início da floração em relação a soma térmica e as unidades fototérmicas. Em ambos os casos a frutificação ocorreu no período do ano com dias mais longos e maiores temperaturas do ar. Portanto, a resposta fotoperiódica das plantas assegura que a frutificação ocorra num período com grande disponibilidade de energia.
5

Flowering time and natural selection in <em>Arabidopsis lyrata</em>

Riihimäki, M.-A. (Mona-Anitta) 12 August 2005 (has links)
Abstract Arabidopsis lyrata is a close outcrossing relative of Arabidopsis thaliana, the model organism of plant physiology and molecular biology. I studied variation in flowering time and the factors shaping the variation within and between A. lyrata populations in different environments. The role of the two important proximate factors determining flowering time, day length and temperature, were studied in climate chambers. The southern A. lyrata populations were found to flower in high frequency and quicker than northern A. lyrata populations in all studied environments, but the reaction of northern populations on long day length was found to be stronger than that of southern populations. Differences in vernalization requirement between A. lyrata populations were found in outdoor common garden, but in the climate chambers the results of vernalization experiments were not consistent. Strength and direction of selection on flowering time and other life history traits were studied in alpine and lowland A. lyrata populations in Scandinavia. Differences in selection were found both between populations and between years. Grazing sheep caused high levels of damage in inflorescences in the alpine population. In the lowland population there was less herbivory, caused by insects and hares. The difference in selection on flowering traits in the two study populations might be partly caused by selective grazing. Completely outcrossing mating system in A. lyrata is due to well developed self-incompatibility system. However, biparental inbreeding is likely to exist in natural populations and it may lead to spatial structuring of genetic variation within populations. I studied the effects of biparental inbreeding on components of fitness in A. lyrata in three different environments. I found inbreeding depression after sib-mating to be substantial. Stressful environment reduced the overall performance of the plants, but had no effect on the magnitude of inbreeding depression. A literature survey indicates that the observed levels of inbreeding depression in self-incompatible A. lyrata were higher than those of self-compatible species. This suggests that self-compatible species have purged some of their genetic load. The genetic basis of flowering time variation in A. lyrata can be further studied by using A. thaliana molecular tools.

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