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Zhodnocení kryptické diverzity ve skupině lakušníku niťolistého (Ranunculus trichophyllus agg.) / Evaluation of cryptic diversity in the group of thread-leaved water-crowfoot (Ranunculus trichophyllus agg.)Hanzlíčková, Johana January 2021 (has links)
Ranunculus trichophyllus agg. (thread-leaved water crowfoot) represents a taxonomically challenging group of aquatic plants in which the presence of several significantly different genotypes and the genome size variation have been recently revealed. The results of previous studies suggest that cryptic taxa occur in this group, being so far overlooked due to considerable morphological reduction and extensivephenotypic plasticity. In this thesis, the variation and genetic relationships of four morphologically similar homophyllous water-crowfoot species was critically assessed in the area of Central Europe, using a combination of modern biosystematic methods (flow cytometry, direct DNA sequencing, morphometric analyses), specially focusing on the complex of R. trichophyllus.. The genome size analysis via flow cytometry was confirmed as a suitable method for determining the studied species; further, several hybrid combinations were revealed using this approach. However, recent interspecific hybridization is rather infrequent in the interest group. The results of DNA analyses indicate an importance of hybridization events in the evolution of sect. Batrachium: all the polyploid taxa studied are probably of allopolyploid origin. Two cryptic taxa within the traditionally recognized species R. trichophyllus have...
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Structural equation modellingMohanlal, Pramod 06 1900 (has links)
Over the past two decades there has been an upsurge in interest in structural equation
modelling (SEM). Applications abound in the social sciences and econometrics, but
the use of this multivariate technique is not so common in public health research.
This dissertation discusses the methodology, the criticisms and practical problems of
SEM. We examine actual applications of SEM in public health research.
Comparisons are made between multiple regression and SEM and between factor
analysis and SEM. A complex model investigating the utilization of antenatal care
services (ANC) by migrant women in Belgium is analysed using SEM. The
dissertation concludes with a discussion of the results found and on the use of SEM
in public health research. Structural equation modelling is recommended as a tool for
public health researchers with a warning against using the technique too casually. / Mathematical Sciences / M. Sc. (Statistics)
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Sistema de métricas de competitividade das nações baseado na estatística multivariada. / A system of national competitiveness metrics based on multivariate statistics.Amaral, Guilherme Soares Gurgel do 05 September 2016 (has links)
Essa tese tem como objetivo o desenvolvimento de métricas para a mensuração dos fatores determinantes da competitividade da economia de países. Parte-se de uma noção estrutural e sistêmica da competitividade, baseada nos estudos de autores relacionados à teoria evolucionária do desenvolvimento econômico, para conceituar competitividade nacional como uma capacidade de os países gerarem competências que darão suporte a seu processo competitivo dinâmico. O debate sobre a criação de métricas de competitividade nacional vem sendo travado nas ciências econômicas e de gestão, e indicam a necessidade de incorporar a mensuração de fatores relacionados à dinâmica da competição no mercado internacional e, principalmente, seus determinantes. Dessa forma, esse trabalho se insere no debate sobre a dinâmica da competitividade nacional baseada em competências para a emergência de vantagens competitivas nas economias nacionais e setores industriais. A proposta aqui desenvolvida consiste na construção de um painel de métricas de indicadores organizado em dimensões de fatores que afetam o desenvolvimento de competências nos países. Metodologias de análise estatística multivariada de dados serão utilizadas para a análise dos dados e, por fim, análises comparativas baseadas em correlações canônicas serão feitas para testar sua validade. / This thesis aims to develop metrics to measure the determinants of competitiveness of national economies. It is based on a structural and systemic notion of competitiveness, based on the studies of authors related to the evolutionary theory of economic development, to conceptualize national competitiveness as the capacity of countries to generate capabilities that will support its dynamic competitive process. The debate on the creation of national competitiveness metrics has been caught in fields of economics and management, and indicates the need to incorporate the measurement of factors related to the dynamics of competition in the international market and especially its determinants. Thus, this work is part of the debate on the dynamics of national competitiveness based on capabilities for the emergence of competitive advantages in the domestic and industrial sectors of economies. The proposal developed here involves the construction of a spreadsheet of indicators organized into dimensions of factors that affect the development of capabilities for competitiveness in countries. Multivariate statistical methods are used to analyze the data and finally comparative analysis based on canonical correlations are made to test their validity. s, multivariate statistical analysis.
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Fizičke karakteristike zemljišta i distribucija teških metala na gradskom području Novog Sada / Physical properties and the distribution of heavy metals in soils of the urban area of Novi SadMihailović Aleksandra 25 August 2015 (has links)
<p>Uzorci zemljišta iz povšinskog sloja dubine 0 - 10 cm<br />prikupljeni su sa 121 lokacije na gradskom području Novog<br />Sada. Ispitivano područje obuhvatilo je površinu (4 x 5)km<sup>2</sup>,<br />koja je podeljena na mrežna polja veličine (400 x 400) m<sup>2 </sup>i u <br />svakom polju uzet je po jedan uzorak. Za 121 uzorak<br />gradskog zemljišta Novog Sada ispitana su fizičko-hemijska<br />svojstva zemljišta, ukupni i pristupačni sadržaj metala (As,<br />Co, Cr, Cu, Mn, Ni, Pb, Zn) i njihova prostorna raspodela.<br />Konturne mape prostorne raspodele metala u zemljištu<br />dobijene su korišćenjem interpolacijske metode običnog<br />kriginga. Za pojedine uzorke izvršeno je razdvajanje čestica<br />po veličinama frakcionisanjem u vodi pomoću sita različitih<br />veličina i identifikovani su minerali prisutni u frakciji prah +<br />glina. Aktivnosti radionuklida „unsupported”<sup> 210</sup>Pb i <sup>137</sup>Cs<br />određene su za jedan deo uzoraka zemljišta u Novom Sadu i<br />za uzorke zemljišta pored fabrike akumulatora u Somboru.<br />Ispitana je i vertikalna distribucija stabilnog i radioaktivnog<br />Pb u zemljištu.</p><p>Na 14 lokacija u Novom Sadu prikupljeno je 35 uzoraka<br />snega direktno sa asfaltnih puteva i sa zemljanih površina u<br />okolini puteva i na pešačkim ostrvima. Raspodela čestica po<br />veličinama i ukupne koncentracije metala (Al, Ca, Cu, Fe, K,<br />Na, Mn, Ni, Pb, Zn) određene su analizom filtriranih uzoraka,<br />a za 4 uzorka ispitana je morfologija čestica i urađena<br />semikvantitativna analiza čestica u suvoj materiji.</p><p>Prilikom obrade rezultata merenja primenjene su metode<br />deskriptivne statistike i multivarijacione statističke analize u<br />cilju identifikacije izvora zagađenja i određivanja povezanosti<br />između samih metala i drugih parametara.</p> / <p>A total of 121 surface soil samples were collected across the central part of Novi Sad covering a surface area (4 km x 5 km). The physicochemical properties, pseudo total and available metal concentrations (As, Co, Cr, Cu, Mn, Ni, Pb, and Zn) were determined. Contour maps of spatial distribution of the investigated metals were obtained using ordinary kriging interpolation method. Separation of different particle <br />size fractions by wet sieving and identification of minerals in the clay and silt fraction for some soil samples were performed. Specific activities of radionuclides “unsupported” <sup>210</sup>Pb and <sup>137</sup>Cs were measured in forty soil samples collected in urban area of Novi Sad and industrial area of Sombor (near a battery manufacturer). Vertical distribution of stable and radioactive Pb for two samples from the industrial soil was examined.</p><p>Thirty five snow samples were collected at fourteen locations near crossroads in Novi Sad. The samples were taken directly from the road surface and from the ground surface in the vicinity of roads and on pedestrian islands. Particle size distribution and total concentration of the metals (Al, Ca, Cu, Fe, K, Na, Mn, Ni, Pb, Zn) were determined for filtered samples. Semi-quantitative analysis of the particles was conducted and morphology of the particles was examined for dry matter of four snow samples. </p><p>Methods of descriptive and multivariate statistics and geostatistics were carried out for the analysis and interpretation of the data.</p>
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Nêutrons, radiação e arqueologia: estudo de caso multianalítico de cerâmicas da tradição borda incisa na Amazônia Central / Neutrons, radiation and archaeology: a multianalytical case study of Incised Rim Tradition ceramics in Central AmazonHazenfratz-Marks, Roberto 09 May 2014 (has links)
Este trabalho é um estudo arqueométrico interdisciplinar envolvendo material cerâmico arqueológico da Amazônia Central, proveniente de dois sítios de grandes dimensões, Lago Grande e Osvaldo, na região de confluência dos rios Negro e Solimões. Procurou-se testar a hipótese de uma rede de trocas entre os antigos habitantes desses sítios, focando em trocas materiais e/ou tecnológicas. Essa hipótese tem implicações para teorias de ocupação da Amazônia Central pré-colonial que procuram relativizar o papel das dificuldades ambientais da floresta tropical como fator limitante para a emergência da complexidade social na região. A caracterização físico-química de fragmentos cerâmicos e argilas próximas aos sítios foi realizada por meio de: análise por ativação com nêutrons instrumental (INAA) para determinação da composição química elementar; espectroscopia de ressonância paramagnética eletrônica (EPR) para determinação da temperatura de queima; difração de raios X (XRD) para determinação da composição mineralógica; e datação de cerâmicas por luminescência opticamente estimulada (OSL). Estudos mostraram que a área dos sítios foi ocupada por culturas produtoras das fases cerâmicas Manacapuru e Paredão, da Tradição Borda Incisa, em torno dos séculos V-X d.C. e VII-XII d.C., respectivamente. Os resultados de INAA foram analisados por métodos estatísticos multivariados, que possibilitaram definir dois grupos químicos de cerâmicas para cada sítio, para os quais não se observaram variações significativas na temperatura de queima e composição mineralógica. A partir do cruzamento com dados arqueológicos, a superposição entre pares de grupos foi interpretada como correlata da existência de uma rede de trocas pretérita, embora não tenha sido possível definir se ela teria ocorrido apenas entre Lago Grande e Osvaldo. Pelo contrário, sugeriu-se, pela comparação de dois grupos químicos de cerâmicas, que Lago Grande participava de uma rede mais extensa de trocas. / This thesis is an interdisciplinary archaeometric study involving archaeological ceramic material from two large archaeological sites in Central Amazon, namely Lago Grande and Osvaldo, on the confluence region of Negro and Solimões rivers. It was tested a hypothesis about the existence of an exchange network between the former inhabitants of those sites, focusing on material and/or technological exchange. That hypothesis has implications for archaeological theories of human occupation of the pre-colonial Central Amazon, which try to relativise the role of ecological difficulties of the tropical forest as a limiting factor for the emergence of social complexity in the region. The physical-chemical characterization of potsherds and clay samples near the sites was carried out by: instrumental neutron activation analysis (INAA) to determine the elemental chemical composition; electron paramagnetic resonance (EPR) to determine the firing temperature; X-ray diffraction (XRD) to determine the mineralogical composition; and dating by optically stimulated luminescence (OSL). Previous studies showed that Osvaldo and Lago Grande were occupied by people which produced pottery classified in the Manacapuru and Paredão phases, subclasses of the Incised Rim Tradition, around the 5-10th and 7-12th centuries BC, respectively. INAA results were analyzed by multivariate statistical methods, whereby two chemical groups of pottery were defined for each archaeological site. Significant variation in firing temperatures and mineralogical composition were not identified for such groups. By integration of the results with archaeological data, the superposition between pairs of chemical groups was interpreted as a correlate of an ancient exchange network, although it was not possible to define if it existed exclusively between Lago Grande and Osvaldo. On the contrary, it was suggested that Lago Grande participated in a more extensive exchange network by comparison of two chemical groups.
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Vizualizace vícerozměrných statistických dat / Visualization of Multivariate Statistical DataMaroušek, Vít January 2011 (has links)
The thesis deals with the possibilities of visualization of multivariate statistical data. Since this is a very broad area the thesis is divided into four sections, two of which are theoretically and two practically oriented. The first section is devoted to theoretical aspects of data visualization. It contains information about the building blocks of graphs, and how the brain processes graphs in various stages of perception. The second section charts the available chart types that can be used to display data. Selected types of graphs for continuous and discontinuous multidimensional data are described in detail. The third section focuses on available software tools for creating graphs. The section describes several programs, with focus on STATISTICA, R and MS Excel. The knowledge gained in previous chapters was sufficient source of information to perform a graphical analysis of multidimensional continuous and discrete data and using advanced analytical methods in the last section. This analysis is performed separately on the data file with continuous variables and on a data file with discontinuous (categorical) variables.
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Nêutrons, radiação e arqueologia: estudo de caso multianalítico de cerâmicas da tradição borda incisa na Amazônia Central / Neutrons, radiation and archaeology: a multianalytical case study of Incised Rim Tradition ceramics in Central AmazonRoberto Hazenfratz-Marks 09 May 2014 (has links)
Este trabalho é um estudo arqueométrico interdisciplinar envolvendo material cerâmico arqueológico da Amazônia Central, proveniente de dois sítios de grandes dimensões, Lago Grande e Osvaldo, na região de confluência dos rios Negro e Solimões. Procurou-se testar a hipótese de uma rede de trocas entre os antigos habitantes desses sítios, focando em trocas materiais e/ou tecnológicas. Essa hipótese tem implicações para teorias de ocupação da Amazônia Central pré-colonial que procuram relativizar o papel das dificuldades ambientais da floresta tropical como fator limitante para a emergência da complexidade social na região. A caracterização físico-química de fragmentos cerâmicos e argilas próximas aos sítios foi realizada por meio de: análise por ativação com nêutrons instrumental (INAA) para determinação da composição química elementar; espectroscopia de ressonância paramagnética eletrônica (EPR) para determinação da temperatura de queima; difração de raios X (XRD) para determinação da composição mineralógica; e datação de cerâmicas por luminescência opticamente estimulada (OSL). Estudos mostraram que a área dos sítios foi ocupada por culturas produtoras das fases cerâmicas Manacapuru e Paredão, da Tradição Borda Incisa, em torno dos séculos V-X d.C. e VII-XII d.C., respectivamente. Os resultados de INAA foram analisados por métodos estatísticos multivariados, que possibilitaram definir dois grupos químicos de cerâmicas para cada sítio, para os quais não se observaram variações significativas na temperatura de queima e composição mineralógica. A partir do cruzamento com dados arqueológicos, a superposição entre pares de grupos foi interpretada como correlata da existência de uma rede de trocas pretérita, embora não tenha sido possível definir se ela teria ocorrido apenas entre Lago Grande e Osvaldo. Pelo contrário, sugeriu-se, pela comparação de dois grupos químicos de cerâmicas, que Lago Grande participava de uma rede mais extensa de trocas. / This thesis is an interdisciplinary archaeometric study involving archaeological ceramic material from two large archaeological sites in Central Amazon, namely Lago Grande and Osvaldo, on the confluence region of Negro and Solimões rivers. It was tested a hypothesis about the existence of an exchange network between the former inhabitants of those sites, focusing on material and/or technological exchange. That hypothesis has implications for archaeological theories of human occupation of the pre-colonial Central Amazon, which try to relativise the role of ecological difficulties of the tropical forest as a limiting factor for the emergence of social complexity in the region. The physical-chemical characterization of potsherds and clay samples near the sites was carried out by: instrumental neutron activation analysis (INAA) to determine the elemental chemical composition; electron paramagnetic resonance (EPR) to determine the firing temperature; X-ray diffraction (XRD) to determine the mineralogical composition; and dating by optically stimulated luminescence (OSL). Previous studies showed that Osvaldo and Lago Grande were occupied by people which produced pottery classified in the Manacapuru and Paredão phases, subclasses of the Incised Rim Tradition, around the 5-10th and 7-12th centuries BC, respectively. INAA results were analyzed by multivariate statistical methods, whereby two chemical groups of pottery were defined for each archaeological site. Significant variation in firing temperatures and mineralogical composition were not identified for such groups. By integration of the results with archaeological data, the superposition between pairs of chemical groups was interpreted as a correlate of an ancient exchange network, although it was not possible to define if it existed exclusively between Lago Grande and Osvaldo. On the contrary, it was suggested that Lago Grande participated in a more extensive exchange network by comparison of two chemical groups.
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USING THE QBEST EQUATION TO EVALUATE ELLAGIC ACID SAFETY DATA: GENERATING A QNOAEL WITH CONFIDENCE LEVELS FROM DISPARATE LITERATUREDickerson, Cynthia Rose 01 January 2018 (has links)
QBEST, a novel statistical method, can be applied to the problem of estimating the No Observed Adverse Effect Level (NOAEL or QNOAEL) of a New Molecular Entity (NME) in order to anticipate a safe starting dose for beginning clinical trials. The NOAEL from QBEST (called the QNOAEL) can be calculated using multiple disparate studies in the literature and/or from the lab. The QNOAEL is similar in some ways to the Benchmark Dose Method (BMD) used widely in toxicological research, but is superior to the BMD in some ways. The QNOAEL simulation generates an intuitive curve that is comparable to the dose-response curve. The NOAEL of ellagic acid (EA) is calculated for clinical trials as a component therapeutic agent (in BSN476) for treating Chikungunya infections. Results are used in a simulation based on nonparametric cluster analysis methods to calculate confidence levels on the difference between the Effect and the No Effect studies. In order to evaluate the statistical power of the algorithm, simulated data clusters with known parameters are fed into the algorithm in a separate study, testing the algorithm’s accuracy and precision “Around the Compass Rose” at known coordinates along the circumference of a multidimensional data cluster. The specific aims of the proposed study are to evaluate the accuracy and precision of the QBEST Simulation and QNOAEL compared to the Benchmark Dose Method, and to calculate the QNOAEL of EA for BSN476 Drug Development.
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Structural equation modellingMohanlal, Pramod 06 1900 (has links)
Over the past two decades there has been an upsurge in interest in structural equation
modelling (SEM). Applications abound in the social sciences and econometrics, but
the use of this multivariate technique is not so common in public health research.
This dissertation discusses the methodology, the criticisms and practical problems of
SEM. We examine actual applications of SEM in public health research.
Comparisons are made between multiple regression and SEM and between factor
analysis and SEM. A complex model investigating the utilization of antenatal care
services (ANC) by migrant women in Belgium is analysed using SEM. The
dissertation concludes with a discussion of the results found and on the use of SEM
in public health research. Structural equation modelling is recommended as a tool for
public health researchers with a warning against using the technique too casually. / Mathematical Sciences / M. Sc. (Statistics)
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Índice de qualidade da água de nascentes no assentamento Paraíso, Alegre, ES / Index water quality of springs in the Paraíso settlement, Alegre, ESAgrizzi, Daniela Vantil 17 August 2012 (has links)
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Previous issue date: 2012-08-17 / Este trabalho teve como objetivo avaliar a qualidade da água de nascentes no assentamento Paraíso, localizado no município de Alegre, ES. A pecuária leiteira é a principal atividade econômica desenvolvida na região e, em 2006, o INCRA, junto aos assentados, iniciou um trabalho de recomposição das APP s das nascentes que resultou atualmente em diferentes tratamentos ao redor dos olhos d água, de acordo com os cuidados e expectativas de cada produtor. Das 25 nascentes existentes, oito foram selecionadas: N1, em meio à floresta remanescente de Mata Atlântica; N2, N3, N4, N5, N6 e N7 estão em recuperação, sendo que as nascentes estão cercadas, porém, variando no tamanho da área cercada, na topografia, no estágio de recuperação alcançado e no tipo de vegetação existente; e a N8, sem cerca e com acesso livre dos animais de criação. Três amostras de água foram coletadas em cada nascente entre novembro/2011 e março/2012 e analisados 17 parâmetros: coliformes totais e termotolerantes, pH, alcalinidade, oxigênio dissolvido (OD), demanda bioquímica de oxigênio (DBO), nitrogênio total, fósforo total, ferro, cálcio, magnésio, temperatura, turbidez, condutividade elétrica (CE) e sólidos suspensos, dissolvidos e totais. Os resultados foram comparados com os padrões normativos da legislação para potabilidade e para qualidade ambiental da água, tendo-se calculado o Índice de Qualidade de Água seguindo metodologia adaptada da Companhia Ambiental do Estado de São Paulo (CETESB), na qual foram retirados os parâmetros pH e OD, por terem sidos considerados não importantes para o cálculo de qualidade para essas nascentes. Técnicas de análise estatística multivariada foram utilizadas para facilitar a interpretação do grande número de parâmetros, por meio da análise de componentes principais (ACP) e análise de agrupamento (AA). A partir da ACP, selecionaram-se dois componentes que explicaram 67,60% da variância total dos dados, e os parâmetros que mais explicam as variações entre as nascentes são: coliformes termotolerantes e totais, DBO, CE, alcalinidade, turbidez, sólidos suspensos totais e temperatura. Na AA três grupos foram formados, distinguindo-se o grupo I, formado pelas nascentes cercadas, o grupo II, composto pela N1, e o grupo III, composto pela N8. O grupo I apresentou a melhor qualidade de água e o grupo III a pior, revelando a importância da proteção de nascentes. A qualidade da água em meio à floresta foi pouco inferior às do grupo I por ter tido mais contato com contaminantes microbiológicos (excrementos de animais silvestres) e por ter recebido maior aporte de matéria orgânica e sedimentos que aquelas protegidas pelo adensamento de gramíneas forrageiras / The objective of this study was to evaluate the water quality of springs in the Paraíso settlement, located in city of Alegre,ES. The dairy production is the main economic activity developed in the region and in 2006, the National Institute of Colonization and Land Reform (INCRA), joined the settlers, started a project of reconstruction of Mandatory Preservation Areas (APP S) of the springs which resulted in different treatments around the springs, according to the treatment and expectations of each producer. Out of 25 existing springs, eight were selected: N1, in an Atlantic Forest remnant; N2,N3,N4,N5,N6,N7 are in recovery, being that the springs are fenced, however, ranging in size of the fenced area, in topography, recovery stages reached and type of existing vegetation; and the N8 wasn t fenced and access the farm animals had free access. Three samples of water were collected in each spring between November/2011 and March/2012 and 17 parameters were analyzed: total and thermotolerant coliforms, pH, alkalinity, dissolved oxygen (DO), biochemical oxygen demand (BOD), total nitrogen, total phosphorus, iron, calcium, magnesium, temperature, turbidity, electrical conductivity (EC) and dissolved suspended total solid. The results were compared to the normative standards of legislation for environmental quality and portability of water and was calculated the Water Quality Index following the method adapted from a Environmental Company of São Paulo (CETESB), in which the parameters pH and DO were taken out because they werent consider important for the quality calculation of these springs. Multivariate statistical analysis technique was utilized to facilitate the interpretation of the large number of parameters thru the Principal Component Analysis (PCA) and Cluster Analysis (CA). Based on the ACP, two components were selected which explained 67.60% of total variance of the data and the parameters best explains the variation between the springs are: total and thermotolerant coliforms, BOD, EC, alkalinity, the turbidity, suspended total solids and temperature. In the CA, three groups were formed, distinguishing group I, formed by the fenced springs, group II, consisting N1 and group III consisting N8. Group I presented the best water quality and group III the worst, revealing the importance of the protection of springs. The water quality in the forest was slightly lower than group I to have had more contact with microbiological contaminants (excrement of wild animals) and to have received greater input of organic matter and sediments than those protected by the density of forage grasses
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