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Dissertations / Theses on the topic 'Comparative correlative'
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Smith, Elizabeth Allyn. "Correlational Comparison in English." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1282105587.
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Ahmiri, Farid. "De l'effacement en syntaxe : processus et modes de signification : etude du statut grammatical du zero dans l'incise, dans la relative et dans la comparative correlative en francais contemporain." Rennes 2, 1993. http://www.theses.fr/1993REN20027.
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L'analyse du statut de l'effacement en grammaire fait l'objet de cette thèse. C'est une étude glossologique du fonctionnement syntaxique de l'absence lexicale qui, commence par critiquer le globalisme et les idées reçues que porte la notion d'ellipse ainsi que ses dérives conceptuels ; trois chapitres, ensuite, démontrent, en les illustrant par des exemples du français contemporain, les trois modes de signification que le zéro peut représenter dans la formalisation des syntagmes de l'incise, (absence sans trace, chapitre 2), de la relative, (zéro chiffre, chapitre 3), et de la comparative en que (cumul systématique des deux procédés, chapitre 4). Du traitement de la similarité des modalités de l'effacement (chapitre 5) se déduit l'analyse de la différence entre processus et procédés, une analyse corroborée par des arguments qui non seulement prouvent les limites glossologiques de l'absence (en grammaire et en rhétorique), mais permettent aussi d'avancer des hypothèses concernant d'autres similaritésThe analysis of the status of effacement in grammar is the aim of this study. It is a glossological study of the syntactic functioning of the lexical absence which starts by criticizing "globalism" and the received ideas concerning the notion of ellipsis and well as its derived conceptuals. Moreover, three chapters prove, with the help of examples from French, the three modes of signification that the zero can represent in the formalization of the interpolated clause's syntagms (absence without trace, ch. 2), of the relative clause (the numbered zero, ch. 3) and eventually of the correlative comparative (systematic accumulation of the one and the other, ch. 4) from the treatment of the similarity of the modes of effacement (ch. 5) can be deduced the analysis of the difference between "process" and "modes", an analysis corroborated by various arguments which not only prove glossological limits of the absence (both in grammar and rhetorics), but also put forward certain hypotheses concerning other similarities
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E, Chen-chun. "The syntax of comparative correlatives in Mandarin Chinese." Thesis, The University of Arizona, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3622174.
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This dissertation is an analysis, assuming the framework of Government and Binding Theory, of the syntactic derivation of comparative correlative constructions (hereafter CCs for short) in Mandarin Chinese. It attempts to evaluate the theoretical adequacy of extant treatments of CCs and propose an alternative analysis to the prevailing adjunct approach.
CC constructions exist crosslinguistically. An English example is The more chocolate I eat, the happier I feel. In Chinese, a simplex CC sentence consists of two non-coordinated clauses; the lexical word yue, which indicates degree, is obligatory in both clauses, as illustrated in (1): (1) tianqi yue1 re, dian-fei yue 2 gao. weather [ YUE1 hot], electricity-fee [YUE 2 high] 'The hotter the weather is, the higher the electricity fee is.'
Unlike the English comparative phrase, which has been shown to undergo A-bar movement in earlier studies, the yue-constituent remains in situ. I argue that yue is generated in [Spec, DegP] and behaves as an indefinite in-situ degree element on a par with an in-situ wh-element (Li 1992; Tsai 1994; Cheng and Rooryck 2000; Cheng 2003a, 2003b). The yue-variable in each clause is unselectively bound (Lewis 1975, Heim 1982, Cheng and Huang 1996) by an implicit CORRELATIVITY OPERATOR and does not undergo A-bar movement.
In addition to the idiosyncratic in-situ yue-phrase, another property of CCs is the syntactic interdependency between the constitutive clauses. Earlier studies (Dikken 2005, Taylor 2006, 2009, Tsao and Hsiao 2002) treat the preceding clause as an adjunct. However, an adjunct approach cannot account for the property of syntactic interdependency. As an alternative, I assume Rizzi's (1997) work on the Split CP Hypothesis, arguing that Chinese CCs implicate the information structure in the left periphery and that they are a type of Focus construction. A Chinese CC sentence like (1) is projected by a null functional head Foc0. The first clause is focused and base-generated in [Spec, FocP] and the second clause is the complement of the null Foc0. The [+focus] feature in Foc 0 licenses the co-occurrence of yue1 and yue2. This alternative analysis can capture not only crosslinguistic commonalities but also the language-internal property of topic-prominence in Chinese.
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Nkhumeleni, Thizwilondi Moses. "Correlation and comparative analysis of traffic across five network telescopes." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1011668.
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Monitoring unused IP address space by using network telescopes provides a favourable environment for researchers to study and detect malware, worms, denial of service and scanning activities. Research in the field of network telescopes has progressed over the past decade resulting in the development of an increased number of overlapping datasets. Rhodes University's network of telescope sensors has continued to grow with additional network telescopes being brought online. At the time of writing, Rhodes University has a distributed network of five relatively small /24 network telescopes. With five network telescope sensors, this research focuses on comparative and correlation analysis of traffic activity across the network of telescope sensors. To aid summarisation and visualisation techniques, time series' representing time-based traffic activity, are constructed. By employing an iterative experimental process of captured traffic, two natural categories of the five network telescopes are presented. Using the cross- and auto-correlation methods of time series analysis, moderate correlation of traffic activity was achieved between telescope sensors in each category. Weak to moderate correlation was calculated when comparing category A and category B network telescopes' datasets. Results were significantly improved by studying TCP traffic separately. Moderate to strong correlation coefficients in each category were calculated when using TCP traffic only. UDP traffic analysis showed weaker correlation between sensors, however the uniformity of ICMP traffic showed correlation of traffic activity across all sensors. The results confirmed the visual observation of traffic relativity in telescope sensors within the same category and quantitatively analysed the correlation of network telescopes' traffic activity.
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Štúriková, Elena. "Correlation based methods for ultrasound blood velocity estimation a comparative study /." Maastricht : Maastricht : Universiteit Maastricht ; University Library, Maastricht University [Host], 1997. http://arno.unimaas.nl/show.cgi?fid=6817.
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Lolli, Linda. "Prolegomena for a comparative study of correlation functions in 2D integrable field theories." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18144/.
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Questo lavoro di tesi si concentra sulla teoria dei Form Factors di operatori locali in due dimensioni. Si espone innanzitutto la teoria dello scattering fattorizzato, propria dei sistemi integrabili, per poi trattare sia classicamente che quantisticamente due modelli integrabili massivi, Sine-Gordon e Sinh-Gordon. Viene esposta l'algebra di Faddeev-Zamolodchikov, per mezzo di cui è possibile trovare lo spazio di Hilbert per modelli integrabili come spazio delle sue rappresentazioni. L'attenzione è infine posta sul regime in cui l'ampiezza relativa alla riflessione solitone-antisolitone nella matrice di scattering è nulla; tale caso si ottiene per valori particolari della costante di accoppiamento del modello di Sine-Gordon, coincidenti con i valori di soglia degli stati legati. Due proposte per l'espressione dei form factors per solitoni sono state prese in considerazione, avanzate una da Lukyanov, l'altra da Babelon, Bernard e Smirnov, tentando un confronto.
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Jönsson, Carl Axel, and Ludvig Hamilton. "Credit Risk and Asset Correlation Modelling for the Swedish Market: A Comparative Analysis." Thesis, KTH, Matematisk statistik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-252315.
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In order to ensure solvency, financial institutions must evaluate their credit risk exposure and determine how much economic capital is required to hold as a cushion. This thesis compares three factor models, namely Asymptotic Single Risk Factor (“ASRF”), Inter-sector and Intra-sector factor models and evaluates how their different characteristics affect the economic capital outcomes. The thesis also investigates how these outcomes are affected when assuming asset dependency through a Student's-$t$ copula. Focus will also be put on how different types and levels of asset correlation affect the models' credit risk results. We use a fictitious loan portfolio consisting of 138 Swedish firms with equity data from between 2007 and 2019 in order to calculate asset correlations and economic capital. Our main findings are that the asset correlations severely impact the outcomes of the credit risk models and that practitioners must calibrate and stress test their models regularly with respect to how correlations vary between different firms. The thesis also finds that using copulas for credit portfolios provides more conservative risk outcomes but makes the models less sensitive to correlation level input.För att finansiella institutioner ska försäkra sig om att vara solventa måste de utvärdera sin exponering mot kreditrisk och därmed avgöra hur mycket ekonomiskt kapital de behöver hålla som buffert. Denna uppsats jämför tre faktormodeller vid namn Asymptotic Systematic Risk Factor (“ASRF”), Inter-sektor, och Intra-sektor med syfte att undersöka hur deras olika karaktärsdrag påverkar estimaten för ekonomiskt kapital. Vi utvärderar även hur utfallen påverkas av införandet av copula-beroende mellan portföljtillgångarna. Fokus kommer även att läggas på hur olika typer och nivåer av korrelation mellan bolag påverkar de olika modellernas kreditriskutfall. Vi använder oss av en fiktiv låneportfölj bestående av 138 svenska bolag med aktieprisdata mellan 2007 och 2019 för att beräkna korrelationer och ekonomiskt kapital. Uppsatsens främsta resultat pekar på att korrelationerna har en väldigt stor påverkan på det ekonomiska kapitalet och att analytiker rekommenderas att kontinuerligt kalibrera och stresstesta sina modeller med avseende på hur korrelationerna kan skilja sig mellan olika bolag. Vi fann även att copula-beroende gav mycket mer konservativa utfall, det vill säga ett högre ekonomiskt kapital, men var mindre känslig för korrelationsnivåerna mellan bolagen i portföljen.
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Hedén, Alice. "Religious pluralism : A comparative study of the correlation between religious societies and stable religious pluralism." Thesis, Uppsala universitet, Teologiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-446803.
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Rajabpour, Mahdi. "Performance of Cumulative Fatigue Damage Rules: Comparative Analysis and Correlation with Material Cyclic Deformation Behavior." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1449595391.
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Mobbs, Richard John. "A comparative analysis of electron correlation in atomic Be and a momentum space investigation of LiH." Thesis, University of Leicester, 1985. http://hdl.handle.net/2381/35736.
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In Part I, the electron correlation problem is briefly reviewed and some approaches to its solution are discussed. In Part II, a partitioning technique used previously to examine correlation trends in individual electronic shells for a series of four-electron ions has been extended and applied to a detailed comparison of four well-correlated wavefunctions for the Be atom. The present analysis of a correlated two-particle density, generalized for any N-electron system, retained all contributions from products of all terms in the wavefunction up to and including the pair-correlation effects. For each correlated description of Be, Coulomb holes and shifts have been evaluated and compared for the K(1S), L(1S), KL(1s) and KL(3S) shells. The inverted nature of the intershell holes, relative to the intrashell effects, has been examined and rationalized in terms of the 2s-2p near-degeneracy which exists in Be. The total Coulomb holes for the two energetically best wavefunctions showed a previously unseen structure which was directly attributable to the intershells. The calculation of partial Coulomb holes and shifts, Δg(r12,r1,)vs.r12 & Δg(p12,P1)vs.P12, allowed us to examine changes in the components of correlation as the position r1 or the momentum p1 of a test electron was varied. Selected one- and two-particle radial and momentum expectation values are also reported along with various radial and angular correlation coefficients. In Part III the partitioning technique, discussed in Part II, has been applied to a momentum space study of electron correlation in a molecular system. The correlation effects embedded in a CI wavefunction for LiH has been examined in terms of the intra- and intershell Coulomb shifts and several one- and two-particle expectation values. Finally, in Part IV we present an overview of correlation coefficients as used, quite extensively, in the discussion of electron correlation. We have examined their construction and have reviewed their application towards this subject.
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Eckblad, Erik. "Correlating Residual Stress with Personal and Professional Characteristics in Aircraft Pilots." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/4784.
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Every day aircraft pilots must successfully resolve significant inflight situations and then manage the possibility of residual psychological and physiological stress. Previous research has shown primary attention is given to presignificant event training and stress management, however there remains an important gap in the current literature regarding postsignificant event stress within the aviation profession. The purpose of this cross-sectional quantitative study was to use the observational lens of stress theory and survey U.S. pilots who have experienced an inflight emergency, looking for correlation between factors such as age, gender, flight experience, and training against a pilot's self-reported level of residual stress. Using snowball sampling methodology, 101 pilots were anonymously surveyed, with 89% responding that they had some level of residual stress via the Impact of Event Scale-Revised instrument. Using multiple linear regression analysis, the correlation between 9 personal and professional characteristics and pilot's stress level was significant, at R2 =.22, adjusted R2=.14, F(9, 91) = 2.8, p < .01. The sample's correlation coefficient was .47, indicating that approximately 22% of the variance in the residual stress was accounted for by the 9 personal and professional characteristics. Findings from this research will help clarify how pilot training and demographics can affect postsignificant event stress. This knowledge will be an important contribution to the existing literature and enhance social initiatives though an increased awareness of residual stress within the pilot profession. The results can be used to increase aviation safety by enabling the industry and government entities to develop and implement effective stress training initiatives.
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Wong, Sau-shing Pierre. "A study of the correlation of share price movements of Taiwan listed companies with cross holdings /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18836288.
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Hayden, Johanna Sayler Michael F. "A comparative study of advanced placement and learning differenced students comparing internal attribution and correlation to hopefulness /." [Denton, Tex.] : University of North Texas, 2009. http://digital.library.unt.edu/permalink/meta-dc-9925.
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Hayden, Johanna. "A Comparative Study of Advanced Placement and Learning Differenced Students: Comparing Internal Attribution and Correlation to Hopefulness." Thesis, University of North Texas, 2009. https://digital.library.unt.edu/ark:/67531/metadc9925/.
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The goal of this research was to determine if there are significant differences in the attribution styles for positive and negative events between students of differing ability and the correlation of these attribution styles to hopefulness. The study examined twelfth grade advanced placement (AP N = 45) students and twelfth grade students with documented learning differences enrolled in college preparatory classes (CP-LD N = 14). Both groups of students came from high socioeconomic backgrounds. The students' internal attributions related to hopefulness were measured with the Hope Scale (Snyder, 1994) which assesses the constructs of agency (will), pathway (way), and produces an overall hopefulness score. Results indicate that AP and CP-LD students had similar measures of internal attribution for positive events, but significantly distinct measures of internal attribution for negative events. However, the AP students show no statistically significant difference from CP-LD students in their measures of agency, pathway, or overall hopefulness.
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Nishimura, Claudio Massumi Oda. "Análise comparativa de algoritmos de correlação local baseados em intensidade luminosa." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/3/3152/tde-14082008-082214/.
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Este trabalho apresentou uma análise comparativa de algumas técnicas de correlações locais baseadas em intensidade luminosa, as quais são: Soma das Diferenças Absolutas, Soma dos Quadrados das Diferenças, Correlação Cruzada Normalizada, Transformada Rank e Transformada Censo. Para as comparações foram adotadas imagens estéreos disponíveis em repositórios de universidades e suas variantes com a inclusão de ruído e variação de intensidade luminosa. Após a implementação dos algoritmos escolhidos e a comparação de seus resultados, foi obtido que a Transformada Censo é um dos métodos com os piores resultados apresentando grande quantidade de correlações erradas. Foram apresentadas modificações para melhorar a performance desse método e os resultados obtidos foram melhores.This work presents a comparative analysis of some local area intensity based correlation algorithm, which are: Sum of Absolute Differences, Sum of Squared Differences, Normalized Cross-Correlation, Rank Transform and Census Transform. For the tests stereo data sets are adopted. These data sets are available at universities websites and their variants with the inclusion of noise and variation of luminosity are created. After implementing the chosen algorithms a comparison were performed and the Census Transform was one of the methods that got the worst results showing large quantity of false correlations. On this work was presented some modifications to improve the performance of the Census Transform and the results obtained were better than the original Census Transform.
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Bolfarine, Henrique. "Comparative evaluation of network reconstruction methods in high dimensional settings." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/45/45133/tde-18052017-001105/.
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In the past years, several network reconstruction methods modeled as Gaussian Graphical Model in high dimensional settings where proposed. In this work we will analyze three different methods, the Graphical Lasso (GLasso), Graphical Ridge (GGMridge) and a novel method called LPC, or Local Partial Correlation. The evaluation will be performed in high dimensional data generated from different simulated random graph structures (Erdos-Renyi, Barabasi-Albert, Watts-Strogatz ), using Receiver Operating Characteristic or ROC curve. We will also apply the methods in the reconstruction of genetic co-expression network for the differentially expressed genes in cervical cancer tumors.Vários métodos tem sido propostos para a reconstrução de redes em alta dimensão, que e tratada como um Modelo Gráfico Gaussiano. Neste trabalho vamos analisar três métodos diferentes, o método Graphical Lasso (GLasso), Graphical Ridge (GGMridge) e um novo método chamado LPC, ou Correlação Parcial Local. A avaliação será realizada em dados de alta dimensão, gerados a partir de grafos aleatórios (Erdos-Renyi, Barabasi-Albert, Watts-Strogatz ), usando Receptor de Operação Característica, ou curva ROC. Aplicaremos também os metidos apresentados, na reconstrução da rede de co-expressão gênica para tumores de câncer cervical.
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Brandt, Jakob, and Emil Lanzén. "A Comparative Review of SMOTE and ADASYN in Imbalanced Data Classification." Thesis, Uppsala universitet, Statistiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-432162.
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In this thesis, the performance of two over-sampling techniques, SMOTE and ADASYN, is compared. The comparison is done on three imbalanced data sets using three different classification models and evaluation metrics, while varying the way the data is pre-processed. The results show that both SMOTE and ADASYN improve the performance of the classifiers in most cases. It is also found that SVM in conjunction with SMOTE performs better than with ADASYN as the degree of class imbalance increases. Furthermore, both SMOTE and ADASYN increase the relative performance of the Random forest as the degree of class imbalance grows. However, no pre-processing method consistently outperforms the other in its contribution to better performance as the degree of class imbalance varies.
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Osborne, Olga Languages & Linguistics Faculty of Arts & Social Sciences UNSW. "Comparative analysis of atypical coordinate structures in Russian and English languages in correlation with field structure of grammatical category coordination." Publisher:University of New South Wales. Languages & Linguistics, 2009. http://handle.unsw.edu.au/1959.4/43738.
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This dissertation examines specific features of atypical coordinate structures (from now referred to as ACS) in both English and Russian languages: those features which differentiate ACS from typical coordinate structures, but nevertheless allow them to keep the status of coordinate structures. Comparing ACS with typical coordinate structures in terms of linguistic norms, this thesis provides a view of ACS as less standard, non-normative forms of syntactic representations of coordinate relations. Most research on coordinate structures focuses either on syntax, or on semantics. This dissertation advocates the expediency of a functional-dynamic approach to ACS, applying the methods of linguistics, psycholinguistics, cognitive linguistics and social linguistics. It argues that coordination is a complex speech-thinking mechanism and that ACS should be analysed by taking into account the cognitive-pragmatic-emotive intentions of the speaker. This dissertation proposes the analysis of structure, semantics and pragmatics of ACS in correlation with their functioning in a text. For the first time the thesis provides a comprehensive comparative analysis of ACS in English and Russian languages. This analysis demonstrates that the syntactically comparable translation of the majority of ACS from English to Russian and vice versa is possible due to the same factors involved in the process of ACS formation in both languages. It also shows that the absence of the same coordinate structure of idiomatic character in the other language makes the adequate translation impossible. This dissertation argues that all types of coordinate structures have the same invariant meaning of MULTITUDE, but syntactically this meaning is represented differently by typical and atypical coordinate structures. The result of the comparative analysis is the proposal of a nucleus-peripheral structure of coordination which represents the diversity of coordinate structures. In the nucleus-peripheral structure typical coordinate structures represent the nucleus and have prototypical status, whereas ACS represent the periphery; different types of ACS are arranged at different distances from the nucleus depending on how many common properties they share with prototypical structures. The fact that this structure can be applied to both English and Russian languages advocates for the common principles of coordinate structures formation mechanism in these otherwise unrelated languages.
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Carvalho, Priscilla Ramos. "Estudo comparativo dos algoritmos hierárquicos de análise de agrupamentos em resultados experimentais." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-31102018-112210/.
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Objetivou-se, com este trabalho, estudar os métodos hierárquicos de análise de agrupamentos (ligação simples, ligação completa, ligação média, centróide e de Ward com base nas distâncias Euclidiana, Euclidiana ao quadrado, Manhattan e Mahalanobis), de modo a identificar qual é o mais adequado para uma base de dados arqueológicos. Utilizou-se uma base de dados fornecida pelo Grupo de Estudos Arqueométricos do IPEN CNEN/SP, na qual foram analisadas 146 amostras de fragmentos cerâmicos de três sítios arqueológicos por análise por ativação com nêutrons instrumental, sendo determinadas as frações de massa de 24 elementos químicos: As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sb, Sc, Sm, Ta, Tb, Th, U, Yb e Zn. Para a determinação do melhor método, foram avaliados os dendrogramas conjuntamente com o valor dos coeficientes de correlação cofenética (CCC), obtidos para cada método. O método da ligação média mostrou-se mais coerente na formação dos agrupamentos, apresentando também os maiores valores do CCC. Por último, um script com funções do programa estatístico R foi desenvolvido para calcular o CCC, com o intuito de auxiliar os pesquisadores a encontrar o método de agrupamento mais apropriado para sua base de dados.The objective of this work was to study the hierarchical methods of cluster analysis (single linkage, complete linkage, average linkage, centroid and Ward with base in the Euclidean distance, Squared Euclidean distance, Manhattan and Mahalanobis) to identify which is the most appropriate in archaeological data set. It was used a data set provided by the Archaeometry Studies Group from IPEN CNEN/SP in which 146 samples of ceramic fragments from three archaeological sites analyzed by instrumental neutron activation analysis, being determined the mass fractions of 24 chemical elements: As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sb, Sc, Sm, Ta, Tb, Th, U, Yb and Zn. For the determination of the best method, it was evaluated the dendrograms together with value of the cophenetic correlation coefficient (CCC) obtained for each method. The average linkage method was more coherent in formation of the clusters, and with higher CCC values. Finally, a script with functions of the R statistical software was developed to calculate the CCC with aim to be a tool for researchers find the most appropriate method of cluster analysis for their data set.
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Kunene, Looksmart Lucky Zamokuhle. "Classroomlevel factors affecting mathematics achievement : a comparative study between South Africa and Australia using TIMSS 2003." Diss., University of Pretoria, 2011. http://hdl.handle.net/2263/25819.
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The purpose of the study was to explore and compare key classroom level factors affecting mathematics learner achievement for South Africa and Australia. The study focused in the classroom where teaching and learning takes place. This is a secondary analysis of classroom level factors influencing Grade 8 mathematics learner achievement using the Trends in International Mathematics and Science Study (TIMSS) 2003. TIMSS 2003 was chosen because it was the latest international study available to measure trends in mathematics learner achievement, where South Africa had participated. Quantitative research approach was employed and a survey research method was used which seeks, among others, to explore relationships and patterns. Survey research method was suitable to provide data that responded to the research questions. The data collection in South Africa and Australia was conducted in October-December 2002 as both countries are located in the Southern Hemisphere. The sample for South Africa consisted of 255 schools with 100% coverage and stratification done by a total of nine provinces, and language. This resulted in 8952 learners tested across the provinces (Joncas, 2004, p. 212). For Australia, the sample consisted of 207 schools with 100% coverage and stratification done by a total of 8 States and Territories and school type. This resulted in 4791 learners participating in the study. The sample included teachers of learners who were selected to participate in the TIMSS 2003 study for South Africa and Australia. The intended target was teachers of all learners at the end of their eight year of schooling. For each participating school, a single mathematics class was sampled and the mathematics teacher of the selected class was asked to complete a mathematics questionnaire. Mathematics teachers of sampled learners responded to questions about teaching emphasis on the topics in the curriculum frameworks, instructional practices, professional training and education and their views on mathematics. The mathematics teacher questionnaire was designed to take about 45 minutes to complete The main question for this study was “What are the key classroom factors that influence learner performance in mathematics?” The three sub questions for the study were: What key variables on classroom level are related to learner achievement in mathematics for South Africa? What key variables on classroom level are related to learner achievement in mathematics for Australia? How do the classroom level factors in mathematics performance of South Africa compare with classroom level factors in Australia? The conceptual framework for the study stressed classroom level factors including instructional quality, which includes teacher background factors, classroom climate, teaching requirements and mathematics curriculum. The framework describes the factors related to classroom interactions within the comprehensive education system, with regard to inputs – process – outputs – outcomes. The selection of variables for the inclusion in the models was guided by the conceptual framework and extensive preliminary analyses. Preliminary statistical analyses included exploring descriptive statistics, Varimax factor analysis, reliability, correlation analysis and stepwise multiple regression analysis. The results of the study indicate that several specific classroom level factors were associated with the higher levels of mathematics achievement of South Africa and Australia. The results for the final South African model were: age of teacher; years been teaching; outside school day grading tests; outside school day other; and computer shortage were identified to predict learner achievement. For Australia ten classroom factors, namely, teacher perception of school climate; teacher perception of school safety; teacher emphasis on mathematics homework; teacher repeat mathematics limiting factors; homework contribute towards learning; work conditions; unhappy learners; shortage of instructional equipment; geometric shapes; and algebraic functions were identified to predict learner achievement. South Africa has factors like teacher background and outside school activities by the teacher. Australia has factors like classroom climate, work conditions and curriculum quality. In the light of schools effectiveness research and school improvement research, a comparative study like this one would require more than one level (classroom level), two or three levels would have been ideal to draw other variables and enrich the analysis, especially the learner level and school level. School effectiveness places an emphasis on the ability and social background of the learners as factors that shape academic performanceDissertation (MEd)--University of Pretoria, 2011.
Science, Mathematics and Technology Education
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Pennequin, Jean-Claude. "Reconnaissance automatique de formes dans des images de simulation et de traitement en radiothérapie." Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL018N.
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La radiothérapie externe est une thérapeutique utilisant les radiations ionisantes pour traiter les cancers locorégionaux. Afin de permettre le contrôle du bon positionnement du patient, des caches de protection et du champ d'irradiation, des images de simulation et de traitement sont comparées. Les limites du champ d'irradiation sont détectées par la méthode de sommation et les limites des caches de protection par la transformée de Hough. Les formes repérées du patient sont traitées comme une chaine de caractères code suivant la technique de Freeman. Afin de réduire les temps de calcul, la technique de corrélation est appliquée dans une seconde période. La corrélation entre les deux images se fait sur des images brutes, de contours et squelettisées. Le maximum de corrélation permet de localiser les coordonnées du meilleur rapport entre l'image de simulation et de traitement. Les résultats sont satisfaisants puisqu'ils permettent de localiser des différences de quelques millimètres
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Almeida, Paulo Roberto Cunha de. "Estudo comparativo de dimensionamento de uma cobertura metálica submetida à ação do vento pela NBR6123 e pelo método da decomposição ortogonal própria." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/17157.
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Medições em túnel de vento e em escala real têm mostrado que as pressões do vento natural não estão totalmente correlacionadas espacialmente. O uso da Decomposição Ortogonal Própria (DOP) permite a obtenção dos desvios padrões das respostas da estrutura a partir da matriz de coeficientes de correlação espacial das pressões do vento nos diferentes pontos de tomadas em túnel. O método indicado pela NBR6123 - Forças devido ao vento em edificações supõe um vento de rajada totalmente correlacionado espacialmente dentro das dimensões da edificação. O objetivo deste trabalho é comparar a resposta estrutural obtida pelos métodos da Decomposição Ortogonal Própria (MDOP) e da NBR6123. Para tal foi escolhida uma estrutura tipo treliça espacial em arco semicircular com 53,00 m de largura, 26,50m de flecha e 92,80m de comprimento. A escolha da estrutura tipo treliça espacial tem o motivo de este tipo de estrutura possuir uma continuidade estrutural capaz de difundir o desvio padrão devido às pressões em uma tomada em uma extremidade da construção para uma resposta em um elemento estrutural na outra extremidade. Foi construído um modelo em escala reduzida para realização de ensaios no túnel de vento do Laboratório de Aerodinâmica das Construções (LAC) da Universidade Federal do Rio Grande do Sul - UFRGS. A partir daí empregou-se o MDOP para a obtenção da resposta estrutural e comparou-se com a resposta obtida pelo método da NBR6123. Os resultados demonstram que os distintos padrões de escoamento em torno do modelo resultam em um carregamento com níveis também distintos de correlação e que o MDOP é uma poderosa ferramenta de análise, permitindo um projeto mais seguro e otimizado da estrutura.Both wind tunnel and real scale measurements have been indicating that the natural wind pressures are not entirely correlated spatially. The use of the Proper Orthogonal Decomposition (POD) allows the acquisition of the structural responses standard deviations from the wind pressures spatial correlation coefficients matrix on the various measurement points in a tunnel. The method shown by the "NBR6123 - Forças devido ao vento em edificações", on the other hand, assumes a gust of wind entirely correlated spatially. The objective of this study was to compare the structural response obtained by the proper orthogonal decomposition methods (POD) with that obtained by the NBR6123 methods. In order to do that, a spatial truss-type structure in semicircular arch was chosen, with a 53,00 m width, a 26,50 m arrow and a 92,80 m length. The choice for a spatial truss structure was made because it has a structural continuity capable of spreading the pressure's standard deviation from a given measurement point on one extremity of the construction, to a response in a structural element on the other extremity. A reduced scale model was built in the Laboratório de Aerodinâmica das Construções (LAC) from the Universidade Federal do Rio Grande do Sul - UFGRS -, in order to perform the tests. Then, the POD\ was employed to obtain the structural responses, which were compared to those obtained employing the NBR6123. The results show that the distinct flow patterns around the model result in a load with also distinct levels of correlation. In conclusion, the POD is a powerful analysis tool that allows a safer and optimized structural design.
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Kong, Xiangning. "Etude de la correlation entre les images des satellites noaa6 et landsat2 : etude de la resolution spatiale sur l'observation de la texture." Paris 6, 1987. http://www.theses.fr/1987PA066456.
Full textAbstract:
Les images satellite mss (provenant du satellite landsat) et avhrr (provenant du satellite noaa) ont des resolutions spatiales differentes. L'existence des decalages inter-images geometriques entraine la necessite de rechercher une superposition precise de ces deux types d'images avant toute comparaison. Dans ce but une methode est mise au point. Pour etablir le processus qui permet de passer de l'image mss a l'image avhrr, la methode de filtrage spatial par transformee de fourier et la methode de masquage sont traitees a cette fin. On etudie enfin l'effet de la resolution sur la texture des images
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Steinhäuser, Jens Peter [Verfasser], and Hartmut [Akademischer Betreuer] Sangmeister. "The Effects of Commodity Prices and Governance on Emerging Economies - Comparative Correlation Research on Brazil and China / Jens Peter Steinhäuser ; Betreuer: Hartmut Sangmeister." Heidelberg : Universitätsbibliothek Heidelberg, 2013. http://d-nb.info/117714803X/34.
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Gaussen, Anthony. "Radiosensibilite predictive des tumeurs differenciees de la thyroide : etude comparative par le fish et la clonogenicite cellulaire : correlation avec la sensibilite des lymphocytes." Paris 11, 1998. http://www.theses.fr/1998PA11T040.
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Seib, Charrlotte. "Health, well-being and sexual violence among female sex workers : a comparative study." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16398/.
Full textAbstract:
Background: Prostitution has been documented in most societies, although the context in which it occurs may vary greatly. In Queensland, Australia, sex workers can operate from legal brothels or privately but all other sectors of the sex industry are prohibited. It is assumed that regulation of the sex industry through legalization leads to better health and social outcomes for sex workers and their clients. However, this assumption has rarely been subjected to empirical scrutiny. Aims: This research examined the occupational health and safety of female sex workers in Queensland and explored the relationship between legislative change, workplace violence, mental health and job satisfaction. Sex workers interviewed in 2003 (after legalisation) were compared to a prior study of this population conducted in 1991 (before official regulation of the sex industry). Further, in-depth analysis of the 2003 cohort compared sex workers employed in legal and illegal sectors, to assess violence, health status and job satisfaction. Methods: Cross-sectional, convenience sampling was used to collect data from female sex workers in 2003. This data was compared with data collected earlier (in 1991) and explored differences in the two samples using bivariate analysis. Similar recruitment strategies on both occasions were used to recruit women from all known sectors of the Queensland sex industry. The 1991 comparison sample (Boyle et al. 1997) included 200 women (aged between 16 and 46 years), and in 2003, 247 women (aged 18 to 57) participated. The 2003 sample included workers from legal brothels (n=102), private sole-operators (n=103) and illegal street-based sex workers (n=42). Using data collected in 2003, this study assessed the relationship between physical and mental health and job satisfaction and two main independent variables, i.e., current work sector and recent workplace violence. Bivariate analysis of physical health and independent variables showed no significant relationships and therefore further analysis was not undertaken. However, analysis of mental health and job satisfaction showed complex interactions between multiple variables and therefore linear modeling was performed to adjust for confounding. Results: Analysis of the 1991 and 2003 samples showed little apparent change over time in self-reported sexually transmitted infections (STIs). There were substantial changes over time in the types of sexual services being provided to clients, with the 2003 sample more likely to provide 'exotic' services. Violence experienced ever in their lifetime differed; in 1991, 29% reported having ever been raped compared with 42% in 2003 (p= <0.01). In 2003, 50% of illegal sex workers reported having ever been raped by a client compared with 12% of private sex workers and 3% of brothel-based sex workers (p=<0.01). Overall, the sex workers reported roughly equivalent job satisfaction to Australian women. A desire to leave the sex industry was most strongly correlated with reduced job satisfaction (p=<0.01). Satisfaction was also relatively low among those whose family was not aware of their sex work (p=<0.01). Similarly, the mental and physical health of this sample was comparable to age-matched women from the general population. Wanting to leave the sex industry was most strongly associated with poor mental health (p=<0.01), as was recent sexual or physical assault by a client (p=0.06) and the woman's main work sector (p=0.05). Illegal sex workers reported substantially lower mental health scores than their counterparts in legal sex work. Conclusions: Self-reported STI diagnosis was high in these samples but the prevalence appears not to have changed over time. Comparing 2003 to 1991, there were trends towards safer and more diverse sexual practices. It is likely the sex industry has 'professionalized' and now includes more sex workers providing specialist, 'exotic' services. This sample of female sex workers reported high rates of violence, with those working illegally at greatest risk. Analysis suggests a complex interaction between variables contributing to mental health and job satisfaction. In general, it appears that the majority of sex workers enjoyed at least as much job satisfaction as women working in other occupations. It also appears that this sample had equivalent mental health to women from the general population, although the sub-group of illegal workers generally had poorer health. Job satisfaction and the extent of workplace hazards (especially risk of violence) were also strongly associated with different sectors of the sex industry. It is probable that legalisation has benefited some (perhaps most) but there are health and safety concerns for those outside the legal framework. Legislative reform should focus on violence prevention, promoting reporting of violent events to police, and further exploration of the impact of legislation on the health of workers in the sex industry.
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Gildemeister, Thomas. "Comparative Toxicity of Eight Model Substances to the Sediment Dwelling Invertebrates Lumbriculus variegatus and Chironomus riparius." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1178202259866-97193.
Full textAbstract:
Existing ecotoxicity data for chemicals vary to a high extent between the environmental compartments water and sediment, since the evaluation of contaminants has historically focused on water exposition. Many anthropogenic chemicals and waste materials, including toxic organic and inorganic chemicals, adsorb to particulate matter and accumulate in sediments, and may thus be a threat to organisms living in the sediment. The invertebrates Chironomus riparius and Lumbriculus variegatus were selected as representatives of endobenthic living organisms. Acute toxicity tests, via water-only exposure, and sediment toxicity tests were conducted with the two endobenthic invertebrates. In sediment toxicity tests, organisms are mainly exposed to sediment- and particle-bound chemicals and dissolved chemical in the pore water. Toxicity data for algae, daphnids, and fish (via water-only exposure) are available for many substances, whereas the existing sediment toxicity data are rather rare. Thus, the interest arises to predict sediment toxicity for sediment-dwelling invertebrates from existing acute toxicity data of tests with water-only exposure. The main emphasis of this work was placed on one metal compound and seven organic chemicals. The objective of this study was fivefold: (1) develop methods and improve existing procedures on acute and sediment toxicity testing of the two invertebrates; (2) conduct both acute toxicity tests via water exposure and long-term sediment toxicity tests for the selected model substances to generate data for comparative discussion; (3) assess correlations among acute toxicity data of the organisms exposed via water-only and correlations among sediment toxicity data of the two endobenthic invertebrates for the eight tested chemicals; (4) assess possible forecasting for sediment toxicity from acute toxicity (via water-only exposure) and (5) assess exposure effects to determine the main exposure route. Acute toxicity data of the eight tested chemicals of D. magna significantly correlated with data of L. variegatus and C. riparius (p<0.05). However, a prediction of toxicity based on D. magna data bears high uncertainty, due to the small data set and high variation in sensitivity of the organisms. Existing sediment toxicity test methods were improved to meet the demand for artificial sediments containing organic matter that serves sufficiently as internal food source for the test organisms, and thus representing natural exposure conditions. However, the sediments that were used for the two organisms to test the selected model substances differed in sediment composition. Therefore, a sediment with the same sediment composition and the same water-to-sediment ratio for both invertebrates was developed, to have similar exposure conditions. In sediment toxicity tests, C. riparius was observed to be more sensitive than L. variegatus and no correlation was observed among data of the invertebrates. For the selected substances, lowest effect concentrations were observed for 3,4-dichloroaniline, whereas effect concentrations were the highest for benzo[a]pyrene. No correlations were found between the acute toxicity data of exposure via the water phase and sediment toxicity data, thus making a prediction of sediment toxicity data impossible. From analytical measurements of chemicals concentration in the compartments overlying, pore water, and bulk sediment, partition coefficients on sediment water partitioning were calculated. The highest partition coefficient ratios for sediment water partitioning were found for the high lipophilic organic substances 4,4-dichlorodiphenyltrichloroethan (DDT) and benzo[a]pyrene. Further, it was found that the main exposure routes in the 28-day sediment toxicity tests were not only chemical but species-dependent. As a result of very differing exposure routes for the tested chemicals and the absence of correlations from the acute to sediment toxicity data, sediment toxicity tests are necessary to assess the toxicity of chemicals on sediment inhabiting organismsIn den meisten standardisierten ökotoxikologischen Untersuchungen zur Abschätzung des Gefährdungspotentials von Chemikalien für Gewässer erfolgt die Exposition der Organismen über die Wasserphase. Viele Schadstoffe, die in die aquatische Umwelt gelangen, adsorbieren aufgrund ihrer physikalisch-chemischen Eigenschaften an die Oberflächen von Schwebstoffen, sedimentieren und erreichen Sedimentkonzentrationen, die möglicherweise eine Gefahr für sedimentbewohnende Organismen darstellen. Im Rahmen dieser Arbeit wurden für benthische Invertebraten Testverfahren etabliert, bei denen eine Exposition der Organismen über das Sediment, hier hauptsächlich über die an ingestierte Sedimentbestandteile gebundene oder über die im Porenwasser gelöste Chemikalie (28-Tage Sedimenttoxizitätstest), und über dieWasserphase (Akuttoxizitätstest) erfolgte. Die Invertebraten Chironomus riparius und Lumbriculus variegatus wurden als typische Vertreter endobenthischer Organismen ausgewählt. Für viele Chemikalien liegen Daten zur akuten Toxizität für Algen, Daphnien und Fische für die Wasserexposition vor. Demgegenüber sind nur wenige Daten zur Toxizität für benthische Organismen weder mit einer Wasser- noch mit einer Sedimentexposition vorhanden. Als Modellsubstanzen wurden eine anorganische und sieben organische Substanzen für die Untersuchungen ausgewählt. Ziele dieser Arbeit waren: (1) die Entwicklung und Verbesserung von bestehenden Methoden zur Bestimmung der akuten Toxizität mitWasserexposition und der Sedimenttoxizität für die beiden Invertebraten; (2) die Durchführung der Tests mit den acht ausgewählten Modellsubstanzen zur vergleichenden Betrachtung; (3) die Beurteilung einer Korrelation der Daten zur Akuttoxizität innerhalb der verschiedenen Organismen mit Wasserexposition und einer Korrelation der Daten zwischen den beiden benthischen Organismen bei Sedimentexposition; (4) die Beurteilung einer Korrelation zwischen Daten der benthischen Invertebraten zur Akuttoxizität mit Wasserexposition und Sedimenttoxizität und (5) die Ermittlung und Bewertung der Expositionspfade. Die Akuttoxizitätsdaten von D. magna korrelieren significant (p<0.05) mit den Daten der beiden Invertebraten. Jedoch ist eine Vorhersage aufgrund des kleinen Datensatzes und der großen Unterschiede in der Empfindlichkeit der Arten abzulehnen. Um einer möglichst natürlichen Expositionssituation in Sedimenten zu entsprechen, wurden künstliche Sedimente mit interner Futterquelle, die auch mit der zu testenden Chemikalie kontaminiert wurde, entwickelt und für die Tests mit den Modellsubstanzen verwendet. Ein Nachteil war die unterschiedliche Sedimentzusammensetzung für die beiden Organismen. Um gleiche Expositionsbedingungen für beide Testorganismen zu gewährleisten, wurde ein artifizielles Sediment mit gleicher Zusammensetzung und gleichem Volumenverhältnis zwischen Sediment und Überstandswasser entwickelt. In den Sedimenttoxizitätstests reagierte C. riparius empfindlicher als L. variegatus. Die Effektkonzentrationen waren am niedrigsten für 3,4-Dichloraniline und am höchsten für Benzo[a]pyren. Die Korrelationen zwischen den Ergebnissen aus Akut- und Sedimenttoxizitstests waren nicht signifikant (p>0.05). Folglich läßt sich die Sedimenttoxizität nicht aus Daten zur akuten Toxizität mit Wasserexposition abschätzen. Aus den analytischen Messungen von Sediment-, Porenwasser- und Überstandswasserproben wurden die Koeffizienten für die Verteilung zwischen Sediment und Wasser berechnet. Für die stark lipophilen Stoffe, 4-Dichlorodiphenyltrichloroethan (DDT) und Benzo[a]pyren wurden die höchsten Koeffizienten errechnet. Weiterhin wurde festgestellt, daß die Hauptexpositionspfade in Sedimenttoxizitätstests einerseits von der Chemikalie und andererseits von der verwendeten Spezies abhängen. Aufgrund der Ergebnisse dieser Arbeit und der Tatsache, daß Sedimente “Senken” für viele Schadstoffe sind, müssen zur Erfassung und Bewertung des Gefährdungspotentials von Chemikalien gegenüber Sedimentbewohnern weiterhin Sedimenttoxizitätstests durchgeführt werden
28
DUBOUCHET, LOCQUET SABINE. "Apport de l'i. R. M. Dans le bilan d'extension des tumeurs de vessie : evaluation comparative avec la t.d.m. et correlation histopathologique : a propos de 57 observations." Lille 2, 1989. http://www.theses.fr/1989LIL2M071.
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Gildemeister, Thomas. "Comparative Toxicity of Eight Model Substances to the Sediment Dwelling Invertebrates Lumbriculus variegatus and Chironomus riparius." Doctoral thesis, Technische Universität Dresden, 2006. https://tud.qucosa.de/id/qucosa%3A24905.
Full textAbstract:
Existing ecotoxicity data for chemicals vary to a high extent between the environmental compartments water and sediment, since the evaluation of contaminants has historically focused on water exposition. Many anthropogenic chemicals and waste materials, including toxic organic and inorganic chemicals, adsorb to particulate matter and accumulate in sediments, and may thus be a threat to organisms living in the sediment. The invertebrates Chironomus riparius and Lumbriculus variegatus were selected as representatives of endobenthic living organisms. Acute toxicity tests, via water-only exposure, and sediment toxicity tests were conducted with the two endobenthic invertebrates. In sediment toxicity tests, organisms are mainly exposed to sediment- and particle-bound chemicals and dissolved chemical in the pore water. Toxicity data for algae, daphnids, and fish (via water-only exposure) are available for many substances, whereas the existing sediment toxicity data are rather rare. Thus, the interest arises to predict sediment toxicity for sediment-dwelling invertebrates from existing acute toxicity data of tests with water-only exposure. The main emphasis of this work was placed on one metal compound and seven organic chemicals. The objective of this study was fivefold: (1) develop methods and improve existing procedures on acute and sediment toxicity testing of the two invertebrates; (2) conduct both acute toxicity tests via water exposure and long-term sediment toxicity tests for the selected model substances to generate data for comparative discussion; (3) assess correlations among acute toxicity data of the organisms exposed via water-only and correlations among sediment toxicity data of the two endobenthic invertebrates for the eight tested chemicals; (4) assess possible forecasting for sediment toxicity from acute toxicity (via water-only exposure) and (5) assess exposure effects to determine the main exposure route. Acute toxicity data of the eight tested chemicals of D. magna significantly correlated with data of L. variegatus and C. riparius (p<0.05). However, a prediction of toxicity based on D. magna data bears high uncertainty, due to the small data set and high variation in sensitivity of the organisms. Existing sediment toxicity test methods were improved to meet the demand for artificial sediments containing organic matter that serves sufficiently as internal food source for the test organisms, and thus representing natural exposure conditions. However, the sediments that were used for the two organisms to test the selected model substances differed in sediment composition. Therefore, a sediment with the same sediment composition and the same water-to-sediment ratio for both invertebrates was developed, to have similar exposure conditions. In sediment toxicity tests, C. riparius was observed to be more sensitive than L. variegatus and no correlation was observed among data of the invertebrates. For the selected substances, lowest effect concentrations were observed for 3,4-dichloroaniline, whereas effect concentrations were the highest for benzo[a]pyrene. No correlations were found between the acute toxicity data of exposure via the water phase and sediment toxicity data, thus making a prediction of sediment toxicity data impossible. From analytical measurements of chemicals concentration in the compartments overlying, pore water, and bulk sediment, partition coefficients on sediment water partitioning were calculated. The highest partition coefficient ratios for sediment water partitioning were found for the high lipophilic organic substances 4,4-dichlorodiphenyltrichloroethan (DDT) and benzo[a]pyrene. Further, it was found that the main exposure routes in the 28-day sediment toxicity tests were not only chemical but species-dependent. As a result of very differing exposure routes for the tested chemicals and the absence of correlations from the acute to sediment toxicity data, sediment toxicity tests are necessary to assess the toxicity of chemicals on sediment inhabiting organisms.In den meisten standardisierten ökotoxikologischen Untersuchungen zur Abschätzung des Gefährdungspotentials von Chemikalien für Gewässer erfolgt die Exposition der Organismen über die Wasserphase. Viele Schadstoffe, die in die aquatische Umwelt gelangen, adsorbieren aufgrund ihrer physikalisch-chemischen Eigenschaften an die Oberflächen von Schwebstoffen, sedimentieren und erreichen Sedimentkonzentrationen, die möglicherweise eine Gefahr für sedimentbewohnende Organismen darstellen. Im Rahmen dieser Arbeit wurden für benthische Invertebraten Testverfahren etabliert, bei denen eine Exposition der Organismen über das Sediment, hier hauptsächlich über die an ingestierte Sedimentbestandteile gebundene oder über die im Porenwasser gelöste Chemikalie (28-Tage Sedimenttoxizitätstest), und über dieWasserphase (Akuttoxizitätstest) erfolgte. Die Invertebraten Chironomus riparius und Lumbriculus variegatus wurden als typische Vertreter endobenthischer Organismen ausgewählt. Für viele Chemikalien liegen Daten zur akuten Toxizität für Algen, Daphnien und Fische für die Wasserexposition vor. Demgegenüber sind nur wenige Daten zur Toxizität für benthische Organismen weder mit einer Wasser- noch mit einer Sedimentexposition vorhanden. Als Modellsubstanzen wurden eine anorganische und sieben organische Substanzen für die Untersuchungen ausgewählt. Ziele dieser Arbeit waren: (1) die Entwicklung und Verbesserung von bestehenden Methoden zur Bestimmung der akuten Toxizität mitWasserexposition und der Sedimenttoxizität für die beiden Invertebraten; (2) die Durchführung der Tests mit den acht ausgewählten Modellsubstanzen zur vergleichenden Betrachtung; (3) die Beurteilung einer Korrelation der Daten zur Akuttoxizität innerhalb der verschiedenen Organismen mit Wasserexposition und einer Korrelation der Daten zwischen den beiden benthischen Organismen bei Sedimentexposition; (4) die Beurteilung einer Korrelation zwischen Daten der benthischen Invertebraten zur Akuttoxizität mit Wasserexposition und Sedimenttoxizität und (5) die Ermittlung und Bewertung der Expositionspfade. Die Akuttoxizitätsdaten von D. magna korrelieren significant (p<0.05) mit den Daten der beiden Invertebraten. Jedoch ist eine Vorhersage aufgrund des kleinen Datensatzes und der großen Unterschiede in der Empfindlichkeit der Arten abzulehnen. Um einer möglichst natürlichen Expositionssituation in Sedimenten zu entsprechen, wurden künstliche Sedimente mit interner Futterquelle, die auch mit der zu testenden Chemikalie kontaminiert wurde, entwickelt und für die Tests mit den Modellsubstanzen verwendet. Ein Nachteil war die unterschiedliche Sedimentzusammensetzung für die beiden Organismen. Um gleiche Expositionsbedingungen für beide Testorganismen zu gewährleisten, wurde ein artifizielles Sediment mit gleicher Zusammensetzung und gleichem Volumenverhältnis zwischen Sediment und Überstandswasser entwickelt. In den Sedimenttoxizitätstests reagierte C. riparius empfindlicher als L. variegatus. Die Effektkonzentrationen waren am niedrigsten für 3,4-Dichloraniline und am höchsten für Benzo[a]pyren. Die Korrelationen zwischen den Ergebnissen aus Akut- und Sedimenttoxizitstests waren nicht signifikant (p>0.05). Folglich läßt sich die Sedimenttoxizität nicht aus Daten zur akuten Toxizität mit Wasserexposition abschätzen. Aus den analytischen Messungen von Sediment-, Porenwasser- und Überstandswasserproben wurden die Koeffizienten für die Verteilung zwischen Sediment und Wasser berechnet. Für die stark lipophilen Stoffe, 4-Dichlorodiphenyltrichloroethan (DDT) und Benzo[a]pyren wurden die höchsten Koeffizienten errechnet. Weiterhin wurde festgestellt, daß die Hauptexpositionspfade in Sedimenttoxizitätstests einerseits von der Chemikalie und andererseits von der verwendeten Spezies abhängen. Aufgrund der Ergebnisse dieser Arbeit und der Tatsache, daß Sedimente “Senken” für viele Schadstoffe sind, müssen zur Erfassung und Bewertung des Gefährdungspotentials von Chemikalien gegenüber Sedimentbewohnern weiterhin Sedimenttoxizitätstests durchgeführt werden.
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Bailey, Carlynne. "Comparative Study of the Chemostratigraphic and Petrophysical characteristics of Wells A-A1, A-L1, A-U1 and A-I1 in the Orange Basin, South Atlantic Margin, Offshore South Africa." Thesis, University of the Western Cape, 2009. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1427_1282897265.
Full textAbstract:
Many hydrocarbon reservoirs are situated in barren sequences that display poor stratigraphic control. Correlation between the wells can become extremely difficult and traditional correlation techniques can prove to be inadequate. Past studies have shown that trace and major element concentrations can be used as a correlation tool. This practice of using geochemical fingerprints to characterize between wells is called Chemostratigraphic analysis. (Pearce et al, 1999) Chemostratigraphy has been recognized as a very important correlation technique as it can be used for rocks of any age, in any geological setting as well as sequences that are traditionally defined as barren. Chemostratigraphic analyses can be used as a means of getting rid of ambiguities within data produced by traditional correlation methods such as Biostratigraphy, Lithostratigraphy and Geophysical Logging. In areas where stratigraphic data is not available it can be used to construct correlation frameworks for the sequences found in the area. The motivation behind this study is that the research is not only worthy of academic investigation, but can also provide the industry with new insights into areas that were previously misunderstood because traditional correlation methods were not adequate. The study area, the Orange basin, is located offshore South Africa and is largely underexplored. The basin, that hosts two gas field namely the Ibhubesi and the Kudu gas fields, has large potential but in the past has not been given due attention with only 34 wells being drilled in the area. The Orange basin has recently been the topic of investigation because of the belief that it may be hosts to more hydrocarbons. This study will utilise Chemostratigraphy to attempt to provide geological information on this relatively under-explored basin. The aim of this research study is to produce a chemostratigraphic framework -scheme for the Orange Basin in order to facilitate reservoir scale interwell correlation. The Objectives of this research study will be to identify chemostratigraphic units or indices, to prove the adequate use of chemostratigraphy as an independent correlation technique and to integrate the chemostratigraphy and petrophysical characteristics of the four wells to facilitate lithological identification.
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Manicardi, Fernando Ricardo. "Estimativas de parâmetros genéticos e estudo comparativo de índices de seleção fenotípico e genético em provas de ganho de peso na raça Nelore." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/74/74131/tde-09052012-104555/.
Full textAbstract:
O presente estudo teve como objetivos estimar os parâmetros genéticos para características de crescimento e perímetro escrotal, bem como avaliar as alterações no ranking dos animais participantes de provas de ganho de peso (PGP) quando diferentes índices de seleção são usados e identificar eventuais erros de seleção. Os índices fenotípicos utilizaram os valores fenotípicos das características e os índices genéticos utilizaram os valores genéticos aditivos para a classificação dos animais. Como dados de crescimento foi analisado o peso aos 120 dias (p120), ao desmame (pdes), aos 12 meses (p12) e aos 18 meses (p18) de 3149, 3958, 2484 e 1872 animais, respectivamente, bem como o ganho de peso do desmame aos 12 meses (gpdes-12) e dos 12 aos 18 meses (gp12-18) com 1455 e 1465 animais, respectivamente. Foi analisado o perímetro escrotal ao desmame (pedes), 12 meses (pe12), 15 meses (pe15) e 18 meses (pe18) de 1535, 1166, 1212 e 852 animais, respectivamente. Os componentes de (co)variância, os parâmetros genéticos e as soluções para os efeitos fixos e aleatórios foram estimados pelo método REML, com o programa VCE6 sob modelo animal e utilizando um arquivo de pedigree com 15.522 animais. Para a comparação de ranking foram utilizados dados de 793 machos nascidos em 2008 e 2009 participantes das PGP. Dois critérios foram usados para a comparação de ranking dos animais, a correlação de ranking de Spearman e os erros de seleção. Para avaliar os erros de seleção duas estratégias foram adotadas: animais que apresentaram índices iguais ou acima da média mais um desvio padrão foram selecionados e os animais que apresentaram índices acima da média, reduzindo com isso a pressão de seleção. As estimativas dos coeficientes de herdabilidade direta foram 0,26, 0,25, 0,13 e 0,15 e materna de 0,20, 0,16, 0,09 e 0,15 para p120, pdes, p12 e p18, respectivamente. As estimativas de herdabilidade direta para gpdes-12 e gp12-18 foram de 0,13 e 0,20, respectivamente. Para as características pedes, pe12, pe15 e pe18 as estimativas de herdabilidade direta foram de 0,56, 0,59, 0,54 e 0,50, e materna de 0,29, 0,29, 0,26 e 0,05, nesta ordem. Em sua maioria, as estimativas estão de acordo com as descritas na literatura. As correlações genéticas entre p120, pdes e p12 com o p18, ficaram abaixo da relatada na literatura. As correlações de ranking apresentaram-se relativamente altas entre os índices fenotípicos e genéticos. Erros de seleção de 19,3 a 73,2% foram observados com a classificação dos animais sendo igual ou maior que um desvio padrão acima da média. Quando a seleção foi obtida nos animais com índice igual ou maior que a média, os erros de seleção permaneceram entre 9,0 e 22,1%. Os resultados deste estudo indicam que a seleção de touros jovens pelos índices fenotípicos pode acarretar em erros na escolha de reprodutores, principalmente quanto maior a pressão de seleção.The objectives of this study were estimate genetic parameters of growth traits and scrotal circumference, as well evaluate changes on ranking of animals submitted to performance tests (PGP) and selection error when two selection indexes were used. The phenotypic index used the phenotypic values, deviated from the mean of the group, to rank the animals and the genetic index used the combined additive genetic values for animals\' ranking. Growth traits comprehended weights at 120 days (p120), at weaning (pdes), at 12 months (p12) and at 18 months (p18) of 3149, 3958, 2484 e 1872 animals, respectively, along with weight gain from weaning to 12 months (gpdes-12) and from 12 to 18 months (gp12-18) measured in 1455 e 1465 animals, in that order. It was analyzed the scrotal circumference at weaning (pedes), at 12 months (pe12), at 15 months (pe15) and at 18 months of 1535, 1166, 1212 e 852 animals, respectively. (Co)variance components, genetic parameters and fixed and random effects solutions were estimated by REML method by VCE program under an animal model methodology and using a pedigree data file composed by 15.522 animals. For animals\' ranking comparison performance test data of 793 animals born in 2008 and 2009 were used. Two criteria were assumed to rank comparison: Spearman ranking correlation and selection error. The evaluation of selection error was realized based on two strategies: animals that presented index equal or greater than the mean plus one standard deviation were selected and animals with index greater than the mean were selected; in this case the selection pressure was reduced. Direct heritability coefficients were estimates as 0.26, 0.25, 0.13 e 0.15, and maternal heritability coefficients estimates were 0.20, 0.16, 0.09 e 0.15 for p120, pdes, p12 and p18, respectively. For gpdes-12 and gp12-18, the estimates of heritability were 0.13 e 0.20, in that order. For scrotal circumference at weaning, 12 months, 15 months and 18 months, the estimates of direct heritability were 0.56, 0.59, 0.54 e 0.50 and for maternal heritability were 0.29, 0.29, 0.26 e 0.05, respectively. In general, those estimations were in agreement with estimation on literature. The genetic correlations between p120, pdes and p12 with p18 were slightly lower than described on other studies. Spearman ranking correlation between phenotypic and genetic index were high. Selection errors between 19.3 and 73.2% were observed when selected animals presented indexes equal or greater than the mean plus one standard deviation. When selecting animals with index greater than the mean, the selection errors observed were between 9.0 and 22.1%. The results indicate that young replacement animals\' selection based on phenotypic index can lead to selection errors, especially when the selection pressure is reduced.
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Lundberg, Robert. "Validation of Biomarkers for the Revision of the CEN/TR 15522-2:2012 Method : A Statistical Study of Sampling, Discriminating Powers and Weathering of new Biomarkers for Comparative Analysis of Lighter Oils." Thesis, Linköpings universitet, Kemi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-156975.
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The revision of the CEN/TR 15522-2:2012 methodology contains new biomarkers to facilitate forensic fingerprinting of the variety of oil types that can be a part of different crimes and the purpose of this project is to validate the biomarkers of the new methodology. Biomarkers were validated by examining corresponding diagnostic ratios compatibility with the internationally used sampling cloth, discriminating power, correlation and simulated weathering sensibility through GC-SIM-MS analysis followed by statistical evaluation with t-tests, diagnostic power, Pearson correlation matrices and MS-PW plots respectively. Results based on most of the diagnostic ratios showed good compatibility with the internationally used sampling cloth, expected patterns of biodegradation and photo-oxidation except for observed photo-oxidation of hydro PAHs and that normative ratios and informative ratios with high diagnostic powers, but with strong correlations for some of the tested ratios, could be identified in diesel oils. Due to delimitations however such as the limited number of oils with similar origins that were analyzed the results should be regarded as guidelines that can be expanded.
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Barberio, Vitaliano, Ines Kuric, Pinuccia Calia, Edoardo Mollona, and Luca Pareschi. "Report of the comparative analysis of the correlation between topics emergent from regional discourses on the one hand, and the awareness and perceptions of the EU (from Eurobarometer) on the other hand." Wirtschaftsuniversität Wien; Università di Bologna, 2018. http://epub.wu.ac.at/6336/1/PERCEIVE_Deliverable_5_2.pdf.
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This document describes the database we developed from data collection and organization activities as described in tasks 5.2 and 5.3 of the PERCEIVE project. The former task, which lasted from month 5 to month 10, consisted of an "Original data collection for exploratory topic modeling". The latter task, which lasted from month 10 to month 13, was named "Topic modeling and qualification". As stated in the Grant Agreement, this description of the database was expected around month 14 (October 2017), while the database itself will be made publically available on-line for further research only after the end of the PERCEIVE project. Indeed, task 5.4, which will last until month 15 is the "Actual Construction of a database of discursive Topics". This document will thus focus on data collection and organization as well as provide an example of the topic models that we are developing coding discourses from different kinds of described datasets.
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Saleur, Hubert. "Phenomenes critiques bidimensionnels." Paris 6, 1987. http://www.theses.fr/1987PA066613.
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Etude theorique des divers aspects des phenomenes critiques bidimensionnels par des methodes essentiellement analytiques: transformation en modeles de champ libre, exploitation de la symetrie conforme. Determination des valeurs exactes d'exposants critiques, et des expressions des fonctions de partition et des fonctions de correlation. Test d'un certain nombre de resultats par des calculs de matrice de transfert ou des simulations de monte carlo
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Mbude-Shale, Beryl Ntombizanele. "Exploring the correlation between language medium and academic achievement: a comparative study of the language of learning and teaching (LoLT) and mathematics results in the 2010 Grade 12 National Senior Certificate examinations in the Eastern Cape." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1001863.
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In 2009, of the 68,129 learners who wrote Matric, only 34,731 learners passed. In 2010, there was an increase in the provincial pass rate causing much excitement across the board. The reality was that of the 64,090 learners who wrote, only 37,345 learners passed. In 2010, a result below 50% was recorded for Mathematics and Physical Science nationally (DBE; 2011). Despite efforts by the Education Department to support MSTE; establishing Mathematics and Science schools, NGOs and HEIs giving extra Mathematics and Science support to students and teachers, the offering of Saturday classes and incubation camps, we still get minimal return on investment. This thesis analyses these results against the backdrop of language planning theory, particularly language-in-education policies, pre and post-apartheid. The correlation between language medium and academic performance in language (LoLT) and Mathematics of Grade 12 learners is explored. Worldwide the issue of low achievement in Mathematics by ESL students is of great concern (Cuevas, 1984). The 2004 Systemic Evaluation sample of learners was in Grade 6 then; in 2010 they wrote Grade 12. The purpose of the systemic evaluation was to provide an insight into the levels of learner performance in Maths, Natural Science and LoLT in Grade 6 (IPSER, 2006). A major finding of the IPSER was that language was an important factor related to learner achievement. A major disparity was observed in this research, that although the Eastern Cape performed below the national average in the three subjects evaluated, the learners for whom LoLT was the same as their home language obtained scores that were significantly higher than those whose home language was different from the LoLT. The provincial average for Mathematics was 23.40% compared to the national average of 27.80%. For LoLT the province scored 30.16 against the national score of 38.03%. Of interest in this study is a juxtaposition of the Matric results of this same group of learners in 2010 and see whether issues that came up then are still significant in mitigating achievement in Mathematics and Language (LoLT). Some research studies have been conducted in South Africa (Adler, 1998; Setati, 1996-2002; Moloi, 2006) identifying the vital role language plays in learning Mathematics, especially for English L2 learners. Building on research and findings of academics such as the late Alexander, Ramani, Joseph, Hendricks, Heugh, Dalvit, Webb and Murray, this thesis suggests that a mother-tongue-based-bilingual approach to education should be adopted as a matter of urgency
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Urbano, Ana Catarina Fernandes. "Clinical relevance of serum cytotoxic t-lymphocyte associated protein 4 (CTLA-4) and correlation with the pro-inflammatory cytokines interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) in feline mammary carcinoma." Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2019. http://hdl.handle.net/10400.5/18970.
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Dissertação de Mestrado Integrado em Medicina VeterináriaThe association between CTLA-4 expression and cancer prognosis has been extensively investigated in recent years, pointing to the link with inflammation, and highlighting the role of the tumor microenvironment (TME), of which inflammatory mediators like cytokines are an important non-cellular component. To the best of our knowledge, no studies on immune checkpoint regulators had been conducted on cats with mammary carcinoma before, nor had cytokine profiles been previously assessed. Thus, we investigated the serum profiles of CTLA-4 and pro-inflammatory cytokines IL-6 and TNF-α in 57 female cats with mammary carcinoma and checked for associations between CTLA-4 and cytokine serum levels. Our results clearly demonstrate that serum CTLA-4 levels are increased in cats with mammary carcinoma when compared to healthy animals (P=0.022). Furthermore, we show a strong positive correlation with TNF-α (R=0.88, P<0.001) and IL-6 levels (R=0.72, P<0.001), advancing the concept of an immunomodulatory role for this regulator in breast cancer pathogenesis. We also show a statistically significant association between higher levels of serum CTLA-4 and less aggressive clinicopathological features: smaller tumors (P<0.001), lower stage (P=0.002), absence of necrosis (P<0.001), no lymph node involvement (P=0.007), no lymphatic vessel invasion (P=0.006), positive hormone receptor status (P=0.007), non-TN status (P=0.041), non-basal status (P<0.001) and low Ki67 index (P=0.001). Our findings further expand this concept by indicating an association with specific breast cancer subtypes, namely, HER-2 positive with CTLA-4 (P<0.001) and TNF-α (P=0.004) and luminal A-like with IL-6 (P=0.020). We could not confirm an association between serum CTLA-4 and cytokines levels and survival due to the small sample size. Nevertheless, our findings suggest a potentially concentration-dependent protective role for serum CTLA-4 and IL-6, as evidenced by higher median survival times in the CTLA-4high (28 vs 22 months for the CTLA-4low group) and IL-6high (28 vs 19 months for the IL-6low group) groups. Conversely, TNF-α seems to be a negative prognostic factor, as shown by the lower median survival in the TNF-αhigh group (16.5 vs 23.5 months for the TNF-αlow group). An intriguing question that remains is how serum CTLA-4 influences or is influenced by the pro-inflammatory cytokines. Assessment of CTLA-4 tumor expression, T-lymphocyte subtypes, and tumor associated macrophages and myeloid derived suppressor cell profiles in the microenvironment, are important features to evaluate in future studies.
RESUMO - RELEVÂNCIA CLÍNICA DA PROTEÍNA 4 ASSOCIADA AO LINFÓCITO T CITOTÓXICO 4 (CTLA-4) E SUA CORRELAÇÃO COM AS CITOQUINAS PRÓ-INFLAMATÓRIAS INTERLEUCINA 6 (IL-6) E FACTOR DE NECROSE TUMORAL ALFA (TNF-α) NO CARCINOMA MAMÁRIO FELINO - A associação entre a expressão da CTLA-4 e o prognóstico no cancro tem sido amplamente investigada, valorizando o papel da inflamação e do microambiente tumoral (TME), do qual mediadores inflamatórios como as citoquinas são uma importante componente não celular. Até à data, não existem estudos sobre reguladores de checkpoint imunológico em gatos com carcinoma mamário, nem foram avaliados perfis de citoquinas. Assim, foram investigados pela primeira vez, os perfis séricos da CTLA-4 e das citoquinas pró-inflamatórias IL-6 e TNF-α em 57 gatas com carcinoma mamário e verificada a existência de associações entre os níveis séricos da CTLA-4 e das referidas citoquinas. Os resultados obtidos demonstram que os níveis de CTLA-4 estão aumentados no soro das gatas com carcinoma mamário, quando comparadas com animais saudáveis (P=0.022). Foi também demonstrada uma correlação forte com os níveis séricos do TNF-α (R=0.88, P<0.001) e da IL-6 (R=0.72, P<0.001), reforçando o papel imunomodulatório deste regulador. Adicionalmente foi encontrada uma associação significativa entre os níveis séricos elevados da CTLA-4, e várias características clinicopatológicas menos agressivas: tumores mais pequenos (P<0.001), estadiamento precoce, (P=0.002), ausência de necrose tumoral (P<0.001), sem envolvimento dos linfonodos (P=0.007), sem invasão linfática (P=0.006), com positividade para os receptores hormonais (P=0.007), subtipo não-TN (P=0.041), subtipo não-basal (P<0.001), e baixo índice Ki67 (P=0.001). Os resultados obtidos ainda revelaram uma associação com subtipos específicos de cancro da mama, nomeadamente o HER-2 positivo com sobre-expressão da CTLA-4 (P<0.001) e do TNF-α (P=0.004) e o luminal A com sobre-expressão da IL-6 (P=0.020). Não foi possível confirmar a associação entre os níveis séricos da CTLA-4 e das citoquinas e o tempo de sobrevivência, devido ao tamanho reduzido da amostra. No entanto, os resultados obtidos sugerem um efeito protetor dependente da concentração da CTLA-4 e IL-6 séricos, como evidenciado pelos tempos medianos de sobrevivência mais altos nos grupos CTLA-4high (28 vs 22 meses para o grupo CTLA-4low) e IL-6high (28 vs 19 meses para o grupo IL-6low). Em contraste, o TNF-α parece ser um fator de prognóstico negativo, como sugere o tempo mediano de sobrevivência mais baixo no grupo TNF-αhigh (16.5 vs 23.5 meses para o grupo TNF-αlow). Permanece a questão de como o CTLA-4 influencia ou é influenciado pelas citoquinas pró-inflamatórias. A avaliação da expressão tumoral da CTLA-4, dos subtipos de linfócitos T, e dos perfis de macrófagos associados ao tumor e células supressoras da linha mieloide no microambiente tumoral, são aspetos importantes a avaliar em estudos futuros.
N/A
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Séméria, Marie-Noëlle. "Etude de circuits submicroniques implantés pour mémoire à bulles magnétiques." Grenoble 1, 1987. http://www.theses.fr/1987GRE10137.
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La technologie necessaire a la realisation de memoires a bulles magnetiques implantees de haute densite (au moins 16 mb/cm**(2)) est etudiee sous differents aspects: le report de motifs submicroniques (0. 3-0. 8 mu m) necessite d'optimiser les moyens classiques de lithographie optique par contact ou projection. A cette fin, une modelisation est utilisee et des experiences comparatives realisees; la realisation des circuits comporte des implantations ioniques: differents materiaux de masque sont proposes (or, silice, polymere). Dans chacun des cas, des realisations concretes de masques graves sont effectuees et analysees; enfin des implantations hydrogene sont realisees. Le fonctionnement des dispositifs est correle aux parametres de l'implantation et au dessin des motifs. Des conclusions pratiques sont tirees sur l'implantation et la technologie compatibles avec un bon fonctionnement des dispositifs
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Su, Yong-Jhih, and 蘇雍智. "Comparative Analyses of Correlation Skew Models." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/67432984590202801846.
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碩士國立臺灣大學
財務金融學研究所
96
In this work, we present a comparative analysis of correlation skew models for pricing of CDOs. All of these models are based on the factor copula pricing framework and can generate correlation skews. The models compared are normal inverse Gaussian copula, stochastic correlation model and local correlation model. By using Gaussian copula as benchmark, the fitness of these models to market data will be tested. Because the subprime mortgage crisis causes structural changes on the credit derivatives market, the fitness before the crisis and after the crisis is compared. Finally, the stability of parameter values over time will be given.
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Su, Yong-Jhih. "Comparative Analyses of Correlation Skew Models." 2008. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2907200823193300.
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Borate, Bhavesh Ram. "Comparative Analysis of Thresholding Algorithms for Microarray-derived Gene Correlation Matrices." 2008. http://trace.tennessee.edu/utk_gradthes/366.
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The thresholding problem is important in today’s data-rich research scenario. A threshold is a well-defined point in the data distribution beyond which the data is highly likely to have scientific meaning. The selection of threshold is crucial since it heavily influences any downstream analysis and inferences made there from. A legitimate threshold is one that is not arbitrary but scientifically well grounded, data-dependent and best segregates the information-rich and noisy sections of data. Although the thresholding problem is not restricted to any particular field of study, little research has been done. This study investigates the problem in context of network-based analysis of transcriptomic data. Six conceptually diverse algorithms – based on number of maximal cliques, correlations of control spots with genes, top 1% of correlations, spectral graph clustering, Bonferroni correction of p-values and statistical power – are used to threshold the gene correlation matrices of three time-series microarray datasets and tested for stability and validity. Stability or reliability of the first four algorithms towards thresholding is tested upon block bootstrapping of arrays in the datasets and comparing the estimated thresholds against the bootstrap threshold distributions. Validity of thresholding algorithms is tested by comparison of the estimated thresholds against threshold based on biological information. Thresholds based on the modular basis of gene networks are concluded to perform better both in terms of stability as well as validity. Future challenges to research the problem have been identified. Although the study utilizes transcriptomic data for analysis, we assert its applicability to thresholding across various fields.
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Yao, Jianchao. "Integrative analysis of high-throughput biological data: shrinkage correlation coefficient and comparative expression analysis." Thesis, 2009. http://hdl.handle.net/2152/ETD-UT-2009-12-403.
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The focus for this research is to develop and apply statistical methods to analyze and interpret high-throughput biological data. We developed a novel correlation coefficient, shrinkage correlation coefficient (SCC), that fully exploits the similarity between the replicated microarray experimental samples. The methodology considers both the number of replicates and the variance within each experimental group in clustering expression data, and provides a robust statistical estimation of the error of replicated microarray data. Applying SCC-based hierarchical clustering to the replicated microarray data obtained from germinating spores of the fern Ceratopteris richardii, we discovered two clusters of genes with shared expression patterns during spore germination. This computational approach is not only applicable to DNA microarray analysis but is also applicable to proteomics data or any other high-throughput analysis methodology.
The suppression of APY1 and APY2 in mutants expressing an inducible RNAi system resulted in plants with a dwarf phenotype and disrupted auxin distribution, and we used these mutants to discover what genes changed expression during growth suppression. We evaluated the gene expression changes of apyrase-suppressed RNAi mutants that had been grown in the light and in the darkness, using the NimbleGen Arabidopsis thaliana 4-Plex microarray, respectively. We compared the two sets of large-scale expression data and identified genes whose expression significantly changed after apyrase suppression in light and darkness, respectively. Our results allowed us to highlight some of the genes likely to play major roles in mediating the growth changes that happen when plants drastically reduce their production of APY1 and APY2, some more associated with growth promotion and others, such as stress-induced genes, more associated with growth inhibition. There is a strong rationale for ranking all these genes as prime candidates for mediating the inhibitory growth effects of suppressing apyrase expression, thus the NimbleGen data will serve as a catalyst and valuable guide to the subsequent physiological and molecular experiments that will be needed to clarify the network of gene expression changes that accompany growth inhibition.text
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Chiou, Denca, and 邱永男. "Correlation between hypertensive effect of Ang II and local NE concentration in rostral ventrolateral medulla：a comparative study between SHR and WKY." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/13517385535528359337.
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碩士國立陽明大學
神經科學研究所
87
The major purpose of this thesis is to elucidate the correlation between depressor effects of Angiotensin II antagonist -- [Sar1,Ala8] Ang II and Norepinephrine(NE) concentration release from Rostral ventral lateral medulla(RVLM). By using the microdialysis technic in the RVLM of the anesthetized rats, we can detect the local NE release of RVLM. In this thesis , we compare the different regulatory mechanism of Ang II and NE release in the RVLM between Spontaneous Hypertension Rat (SHR) and Wistar Kyoto rat (WKY). After unilateral microinjection Ang II 10nmole/5μl to RVLM , the NE concentration of RVLM of SHR, significantly increase (p<0.001) from control 0.0672±0.0088 pg/10μl to 0.0924±0.0022 pg/10μl. The NE concentration of RVLM of WKY significantly increase (p<0.05) from control 0.0604±0.0038 pg/10μl to 0.0865±0.0054 pg/10μl . In other hand , after intravenous Ang II 10nmole/5μl in 0.2ml NaCl， the NE concentration of RVLM significantly increase (p<0.05) from control 0.0604±0.0038 pg/10μl to 0.0786±0.0053 pg/10μl in WKY。After unilateral microinjection [Sar1,Ala8] Ang II (Ang II antagonist 500 pmole/5μl) to RVLM of SHR , the NE concentration of RVLM significantly decrease (p<0.05) from control 0.0571±0.0054 pg/10μl to 0.0382±0.0018pg/10μl, The NE concentration of RVLM of WKY significantly decrease (p<0.05) from the control 0.0461±0.0034 pg/10μl to 0.0344±0.0026 pg/10μl. When Ang II and[Sar1,Ala8] Ang II are combined and unilaterally microinjected to RVLM with either 500 pmole/2.5μl or 10 nmole/2.5μl. the NE concentration in the RVLM of SHR is not significantly change from the control group 0.0459±0.0033 pg/10μl or in the drug injected group 0.0475±0.0034 pg/10μl or 0.0424±0.0035 pg/10μl , the NE concentration in the RVLM of WKY rats also not significantly changed from the control group 0.0425±0.003 pg/10μl to drug injected group 0.0428±0.0015pg/10μl or 0.0374±0.0038pg/10μl. The physiological effect of Ang II in RVLM is rising BP, and the effect of Ang II antagonist is lowering BP. When Ang II and Ang II antagonist are combined injected into RVLM , BP is not changed due to [Sar1,Ala8] Ang II inhibits the Ang II effects of NE release in RVLM. These results from Ang II increase NE release in RVLM neuronal cell ;and [Sar1,Ala8] Ang II inhibits NE release from RVLM neuronal cell. And we suggest that there are positive relation between BP and local NE concentration in the RVLM. [Sar1,Ala8] Ang II decrease BP may due to its inhibition on the interaction Ang II antagonist of endogenous Ang II and NE of RVLM.
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Lo, Fang-Yi, and 羅芳宜. "Identification and characterization of novel cancer-related genes in lung cancer by array-comparative genomic hybridization, clinical correlation, and functional studies." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/cz926h.
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博士國立臺灣師範大學
生命科學研究所
99
Cancer-related genes show racial differences. Therefore, identification and characterization of DNA copy number alteration regions in different racial groups help to dissect the mechanism of tumorigenesis. Here, DNA copy number alteration profile was analyzed by array-comparative genomic hybridization (array-CGH) for 40 Asian and 20 Caucasian lung cancer patients. We identified 20 chromosomal imbalance regions harboring 459 genes for Caucasian and 17 regions containing 476 genes for Asian lung cancer patients. Among the genes identified, the ion transport and chromatin remodeling are the two main common biological processes altered in both Asia and Caucasian populations. Interestingly, genes involved in Wnt receptor signaling pathway were unique in Asian lung cancer, whereas Caucasian lung cancer was addictive to cell surface receptor linked signal transduction and G-protein coupled receptor protein signaling pathways. Genes residing within the chromosomal imbalance regions were integrated with gene expression databases to identify 214 potential cancer-related genes. Four racial-specific candidate oncogenes were validated in 164 patients using quantitative polymerase chain reaction (q-PCR), chromogenic in situ hybridization (CISH), reverse transcriptase-q-PCR, and immunohistochemistry. These four genes were ARHGAP19 (10q24.1) functioning in Rho activity control, FRAT2 (10q24.1) involved in Wnt signaling, PAFAH1B1 (17p13.3) functioning in motility control, and ZNF322A (6p22.1) involved in MAPK signaling. Mean gene dosage and mRNA expression level of the four candidate genes in tumor tissues were significantly higher than the corresponding normal tissues (P<0.001~P=0.06). PAFAH1B1 which showed amplification and overexpression in both Asian and Caucasian lung cancer patients was further characterized in cell, animal, and clinical models. The PAFAH1B1 mRNA and protein overexpression frequency were 62.4% (63/101) and 57.4% (58/101) in 101 lung cancer patients. The results indicated that mRNA and protein overexpression level of PAFAH1B1 was significantly associated with late stage (mRNA: P=0.008, protein: P=0.008) and poor survival in lung adenocarcinoma (P=0.020) and male patients (P=0.049). Collectively, our study provides the first database revealing common and differential chromosomal imbalance regions among lung cancer from Asians and Caucasians. Four validation methods in a large patient cohort confirm our database. The cell and animal studies verify a novel metastasis-promoting oncogene, PAFAH1B1.
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Li, Wen-Hui, and 李玟慧. "The correlation between the design of parental leave policy and women's employment behavior-a comparative study of United Kingdom, Sweden and Taiwan." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/44062057933087248529.
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碩士國立中正大學
勞工所
94
Abstract Women’s employment condition is influenced by many factors. The responsibility of taking care of children is one of the reasons. It makes women have to face a difficult choice between their families and work. Western countries have developed family policies to help working parents to balance between their work and families as well as to promote the equality of employment for both sexes. Among family policies, some scholars believe that ideal parental leave policies are helpful to women’s employment, especially to the mothers with young children. Therefore, this research attempts to analyze the policies in United Kingdom, Sweden and Taiwan in a comparative perspective, and to discuss how the design of parental leave policies has correlation to women’s employment behavior. The results showed United Kingdom’s relative policies have not fully support working women with young children; therefore most women with young children have to either be in intermittent employment or work as a part-time employee. On the other hand, these two problems in Sweden seem less. It reflects that Sweden has better planed parental leave policies. However, women with young children in Taiwan are either be in intermittent employment or have a long break from their career; some of them even never come back to work. This tells us Taiwan’s relative policies do not support mothers with young children to have jobs. There is plenty of room for the parental leave policies in Taiwan to be improved. There are many things worth thinking again on the concept of legislation. To the design of parental leave policies, there are a lot of details needed to be planed carefully. Key Words: parental leave; women employment; intermittent employment; United Kingdom; Sweden
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"The correlation between personal jurisdiction and the enforcement of foreign judgments (a comparative law study about Canada, the United States and Mexico)." Tulane University, 2007.
Find full textAbstract:
Canada, the United States and Mexico offer a very interesting microcosm. On one side these three countries have strong economic, commercial and cultural ties with each other, but on the other hand there are significant and contrasting differences among each one of them. Differences in paradigms, approach, concepts, structures, procedures, et cetera While Canada is a Constitutional Monarchy with a Parliamentarian form of government, the U.S. and Mexico are Republics with a Presidential system. These three countries are known to be federal States, but their actual practice of federalism is very different in each one of them Furthermore, while Mexico's legal system belongs to the Romano-Germanic Tradition; most of the U.S. and Canada belong to the tradition of the Common Law. And yet there is even more, at different levels Puerto Rico and Louisiana in the United States, as well as Quebec in Canada are rooted in the Romano-Germanic Tradition. Accordingly, the Common Law and the Romano-Germanic traditions have to coexist harmoniously in the interaction that the domestic systems of Puerto Rico, Lousiana and Quebec have with the federal sphere of their respective counties This is the legal context in which our three countries have to coexist, interact and work together, and I think that these goals may only be achieved successfully if we understand and respect our respective legal identities in terms of that which is unique to each other, in terms of that which is different in each other, in terms of the goals that we do not have in common, in terms of the common goals that we have in common, in terms of that which we may want to achieve together, and also in terms of that what we can and should learn from each other Still, I truly believe that there are many important lessons that Mexico and world have to learn from these functional coexistences. At least in Canada this situation has driven to produce important developments in that what today is known as the Canadian Bijuralism. And even more, in my opinion---without having conscience of it---Canadians are developing the model that will frame supra-national law and global legal interaction in the twenty-first century In this sense, it would be ideal---and even desirable---to count with a broader and comprehensive view of the interaction between globalization the Law, as well as its actual effects and implications, but my goal is rather monographic This work aims to discuss one specific issue, the correlation between the assumption of personal jurisdiction by the issuing court over non-resident defendants (when the defendant has not appeared before the court, has challenged its jurisdiction or has not expressly submitted to such jurisdiction) and the enforcement of foreign judgments in the three countries of the North American subcontinent, namely Canada, the United States and Mexicoacase@tulane.edu
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Vilar, Catarina Eloísa Carpinteiro. "Dificuldades de aprendizagem e psicomotricidade : estudo comparativo e correlativo das competências de aprendizagem académicas e de factores psicomotores de alunos do 2º e 4º ano do ensino básico, com e sem dificuldades na aprendizagem." Master's thesis, 2010. http://hdl.handle.net/10400.5/2828.
Full textAbstract:
Mestrado em Reabilitação PsicomotoraO presente artigo pretende expressar a revisão bibliográfica realizada no âmbito do estudo das Dificuldades de Aprendizagem e da Psicomotricidade. Primeiramente, analisa-se o conceito e definição de Dificuldades de Aprendizagem, evidenciando as características apresentadas por crianças com dificuldades de aprendizagem. Procura-se também explicitar os processos e dificuldades ligadas às componentes académicas da Leitura, da Escrita e da Matemática. Em seguida, é desenvolvido o conceito de Psicomotricidade e de desenvolvimento psicomotor, descrevendo os factores psicomotores da Estruturação espácio-temporal, da Praxia global e da Praxia fina. Por fim, tenta-se compreender as possíveis relações existentes entre a Psicomotricidade e as Dificuldades de Aprendizagem.
The following article aims to express the bibliographic research embraced in the study of Learning disabilities and Psychomotricity. First it’s analysed the concept and definition of Learning disabilities, showing the characteristics presented by children with learning disabilities. It’s explained the process and difficulties related with the academic components of Reading, Writing and Mathematics. Next, it’s developed the concept of Psychomotricity and psychomotor development, describing the psychomotor factors of Spatio Temporal structuration, Macro motricity and Micro motricity. At last, we try to understand the possible connection between Psychomotricity and Learning disabilities.