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Relationships between Student Attendance and Test Scores on the Virginia Standards of Learning Tests.Cassell, Jeffrey 15 December 2007 (has links) (PDF)
This study examines the relationship between student attendance and student test scores on a criterion-referenced test, using test scores of all 5th graders in Virginia who participated in the 2005-2006 Standards of Learning tests in reading and mathematics. Data collection for this study was performed with the cooperation of the Virginia Department of Education using a state database of student testing information. Pearson correlation coefficients were determined for the overall student population and for the subgroups of economically disadvantaged, students with disabilities, limited English proficient, white, black, and Hispanic. The results of this study indicate that there is a significant positive correlation (p<.01) between student attendance, as measured by the number of days present, and student performance on the Virginia SOL test, a criterion-referenced test.
Positive correlations were found between student attendance and student test scores for all subgroups. The correlation between student attendance and student performance on the SOL mathematics test was higher than the correlation for the same variables on the English test. The correlation for the overall student population on the English SOL test was higher than the correlation for any subgroup on the English SOL test. Only the LEP and Hispanic subgroups had higher correlations on the mathematics test than the overall student population. This study will contribute to a growing body of research resulting from the enactment of the No Child Left Behind legislation and the national attention that this legislation has focused on student attendance and student performance on standardized tests.
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GLR Control Charts for Monitoring a ProportionHuang, Wandi 19 December 2011 (has links)
The generalized likelihood ratio (GLR) control charts are studied for monitoring a process proportion of defective or nonconforming items. The type of process change considered is an abrupt sustained increase in the process proportion, which implies deterioration of the process quality. The objective is to effectively detect a wide range of shift sizes.
For the first part of this research, we assume samples are collected using rational subgrouping with sample size n>1, and the binomial GLR statistic is constructed based on a moving window of past sample statistics that follow a binomial distribution. Steady state performance is evaluated for the binomial GLR chart and the other widely used binomial charts. We find that in terms of the overall performance, the binomial GLR chart is at least as good as the other charts. In addition, since it has only two charting parameters that both can be easily obtained based on the approach we propose, less effort is required to design the binomial GLR chart for practical applications.
The second part of this research develops a Bernoulli GLR chart to monitor processes based on the continuous inspection, in which case samples of size n=1 are observed. A constant upper bound is imposed on the estimate of the process shift, preventing the corresponding Bernoulli GLR statistic from being undefined. Performance comparisons between the Bernoulli GLR chart and the other charts show that the Bernoulli GLR chart has better overall performance than its competitors, especially for detecting small shifts. / Ph. D.
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Distribuční dopady inflace v České republice / Distributional Effects of Inflation in the Czech RepublicLinhartová, Petra January 2015 (has links)
Consumer price index captures the changing costs of the consumer basket of a typical household. Despite differences in spending patterns, change in con- sumer price index is used as a measure of inflation for the whole population. The aim of this thesis is to assess how close to the official inflation rate house- holds are and determine which groups have significantly different inflation. Using the Czech data from the Household Budget Survey over the 1990-2012 period we calculated specific inflation for each household in our sample. We first found out that on average only two thirds of households are close to the official inflation rate, which led us to the construction of subgroup price indices. In the empirical part, we examined the effect of household characteristics on inflation by applying the fixed effects estimation. We found that low-income households, pensioners, households in urban areas and households with few members have higher than average inflation.
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Problema do subgrupo oculto em grupos nilpotentes / Hidden subgroup problem in nilpotent groupsFernandes, Tharso Dominisini 13 March 2008 (has links)
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Previous issue date: 2008-03-13 / Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / Quantum computers may solve certain problems asymptotically faster than the classical computers. Quantum algorithms, such as Shor s algorithm, may be considered as a particular case of the Hidden Subgroup Problem (HSP). The HSP consists in finding a subgroup H of a group G by evaluating a function f, which is constant in cosets of H and distinct for each coset. The HSP for Abelian groups is efficiently solved in a quantum computer, but is quantum computers can solve the HSP in non-Abelian groups efficiently? This question has been regularly discussed by the scientific community due to the importance of some applications, such as the graph isomorphism problem and the short vector in a lattice. In this dissertation we review the Ivanyos et al. (2007a) that address HSP in nilpotent groups of class 2. We make a brief review on Quantum Computing; we address some characteristics of nilpotent groups and solvable groups, with special attention to nilpotent groups of class 2; we discuss the standard method of solution of the HSP in Abelian groups; we present the main characteristics of the polycyclic sequences and important reductions of the HSP in classes of nilpotent groups using the properties of polycyclic sequences. Finally, we present an efficient algorithm to solve the HSP in nilpotent groups of class 2. / Computadores quânticos prometem resolver certos problemas assintoticamente mais rápido do que os computadores clássicos. Algoritmos quânticos, como o algoritmo de Shor, podem ser considerados casos particulares do chamado Problema do Subgrupo Oculto(PSO). O PSO consiste em encontrar um subgrupo H de um grupo G por meio de avaliações de uma função f que é constante em classes laterais de H e distinta em classes laterais diferentes. O PSO em grupos abelianos é resolvido eficientemente em um computador quântico, mas será que os computadores quânticos podem resolver o PSO em grupos não abelianos? Esta questão tem sido discutida regularmente pela comunidade científica devido a importantes aplicações, como é o caso do problema de isomorfismo de grafos e do problema do menor vetor em um reticulado. Nesta dissertação é feita uma revisão do trabalho de Ivanyos et al. (2007a), o qual apresenta uma solução para o PSO em grupos nilpotentes de classe 2. Com esta finalidade, é elaborada uma breve revisão sobre a Computação Quântica; são mostradas algumas características dos grupos nilpotentes e dos grupos solúveis, dando uma atenção especial aos grupos nilpotentes de classe 2; é exposto o método padrão de solução do PSO em grupos abelianos; também são exibidas as principais características de sequencias policıclicas e reduções¸de grupos nilpotentes usando as propriedades de sequencias policıclicas
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Morfometria geométrica e banco de dados na investigação de problemas biológicos em Culicidae. / Geometric morphometry and database in the investigation of biological problems in Culicidae.Fonseca, Flavia Virginio 09 March 2018 (has links)
Enquanto muitas espécies de mosquitos são conhecidas por sua importância epidemiológica, a capacidade vetorial de algumas ainda não é clara. A identificação taxonômica, bem como a sexagem dos espécimes de Culicidae são essenciais para qualquer estudo ou ação, entretanto muitas vezes caracteres-chave estão danificados ou são restritos a uma fase de vida do animal. Em espécies crípticas, a identificação dos espécimes também pode ser prejudicada, o que dificulta, sobretudo, a compreensão da atividade vetorial em mosquitos. A morfometria geométrica alar, uma técnica barata e precisa para identificação de sutis dissimilaridades morfológicas, pode contribuir para a resolução destes tipos de problemas. O grupo de pesquisa MosquitoLab aplica esta técnica há mais de 10 anos e acumulou milhares imagens de asas com seus respectivos metadados. Estas informações, se organizadas como banco de dados relacional, podem permitir a sistematização do uso, consulta e armazenamento dos dados, além de viabilizar novos estudos e servir também como base para aplicações de identificação automática de mosquitos. Portanto, os objetivos deste trabalho foram avaliar a utilidade da morfometria geométrica alar para a resolução de dois problemas biológicos: dimorfismo sexual e espécies crípticas, e desenvolver um protótipo de plataforma para armazenamento de dados biológicos relacionados à morfometria de asa, por meio de um banco de dados relacional e um sistema web nomeado WingBank. Com base na técnica de morfometria geométrica alar, dois estudos de caso foram realizados: a) avaliação do dimorfismo sexual de 10 espécies de mosquitos de interesse médico e, b) diferenciação morfológica alar de Anopheles strodei s.s. e Anopheles arthuri s.l. com base em dois diferentes conjuntos de pontos anatômicos. Para construção do protótipo do WingBank uma equipe multidisciplinar realizou levantamento de requisitos, modelagem e criação do banco de dados relacional, e implementação de uma plataforma web. Os resultados referentes ao dimorfismo sexual alar apresentaram significativa diferenciação entre os sexos e padrões específicos de forma alar em todas as espécies estudadas. Os pontos anatômicos alares mais variáveis foram os das regiões proximal e distal das veias mediana e radial. Fêmeas apresentaram asas significativamente mais largas e curtas do que os machos. Diferenciação morfológica alar entre as espécies crípticas avaliadas foi observada em ambos os conjuntos de dados (18 e 22 pontos), sendo que no conjunto de 22 pontos com alometria, foi mais evidente. Os pontos anatômicos mais variáveis nas análises com os conjuntos de 18 e 22 pontos foram 1, 2 e 17, e 1, 2, 19, respectivamente. Finalmente, o protótipo WingBank foi implementado com dados referentes a 77 espécies pertencentes a 15 gêneros de Culicidae. Ao todo foram catalogados 13.287 registros de asas, dos quais 2.138 já estão disponibilizados a partir do presente trabalho, para uso de terceiros. Globalmente, este é o maior banco de dados de asas de Culicidae de que temos conhecimento. / While many species of mosquitoes are known for their epidemiological importance, the vector capacity of some is still unclear. Taxonomic identification and sexing of Culicidae specimens are essential for any study or action; however, often key characters are damaged or restricted to a stage of life of the animal. In cryptic species, the identification of specimens can also be damaged, which makes it difficult to understand the vector activity in mosquitoes. Geometric morphometry, an cheap and precise technique for identifying subtle morphological dissimilarities, may contribute to the resolution of these types of problems. The MosquitoLab research group has applied this technique for more than 10 years and has accumulated thousands of wing images with their metadata. This information, if organized as a relational database, may allow the systematization of the use, consultation and storage of the data, besides making possible new studies and lso serve as a basis for applications of automatic identification of mosquitoes. Therefore, the aims of this work were to evaluate the usefulness of the geometric morphometry to solve two biological problems: sexual dimorphism and cryptic species, and to develop a prototype of plataform for the storage of biological data related to wing morphometry, by means of a relational database and a web system named \"WingBank\". Based on the technique of wing geometric morphometry, two case studies were carried out: a) evaluation of the sexual dimorphism of 10 species of mosquitoes of medical importance and b) wing morphological differentiation of Anopheles strodei s.s. and Anopheles arthuri s.l. based on two different sets of landmarks. In order to build the WingBank prototype a multidisciplinary team performed requirements survey, modeling and creation of the relational database, and implemented a web platform. The results regarding wing sexual dimorphism showed significant differentiation between the sexes and specific patterns of wing shape in all species studied. The most variable landmarks were those of the proximal and distal regions of the medial and radial veins. Females showed slightly and significantly wider and shorter wings than males. Wing morphological differentiation between An. strodei s.s. and An. arthuri s.l. was observed in both sets of data (18 and 22 landmarks), but in the set of 22 with allometry, it was more evident. The most variable landmarks in the analyzes with the sets of 18 and 22 landmarks were 1, 2 and 17, and 1, 2, 19, respectively. Finally, the WingBank prototype was implemented with data referring to 77 species belonging to 15 genera of Culicidae. In all, 13,287 wing records were cataloged, of which 2,138 are from the present work, already available for use by third parties. Globally, as far as we know, this is the largest database of Culicidae wings.
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Decomposição de grupos e invariantes ends /Ricieri, Marina Marcia. January 2007 (has links)
Orientador: Ermínia de Lourdes Campello Fanti / Banca: Maria Gorete Carreira Andrade / Banca: Pedro Luiz Queiroz Pergher / Resumo: Um grupo G se decompõe sobre um subgrupo S se G þe um produto livre com subgrupo amalgamado S ou uma extensão HNN. Neste trabalho, propusemo-nos a relacionar, sob alguns aspectos, decomposição de grupos e invariantes ends. Mais precisamente, demonstramos os teoremas da forma normal para produtos livres com subgrupo amalgamado e extensões HNN e apresentamos alguns resultados relativos 'a teoria de grafos, ends de grupos e pares de grupos, finalizando com a prova de um teorema de Kropholler e Roller, sobre decomposição de grupos, envolvendo a obstrução sing. / Abstract: A group G splits over a subgroup S if G is a free product with amalgamated subgroup S or an HNN extension. In this work, we are concerned in relating, under some aspects, splittings of groups and invariants ends. More precisely, we prove the theorems normal forms for free products with amalgamated subgroup and HNN extensions and we present some results related with the theory of graphs, ends of groups and pairs of groups, concluding with the proof of a theorem by Kropholler and Roller, on decomposition of groups, involving the obstruction sing. / Mestre
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Construals of Human Rights Law: Protecting Subgroups As Well As Individual HumansNolan, Mark Andrew, mark.nolan@anu.edu.au January 2003 (has links)
This research develops the social psychological study of lay perception of human rights and of rights-based reactions to perceived injustice. The pioneering work by social representation theorists is reviewed. Of particular interest is the use of rights-based responses to perceived relative subgroup disadvantage. It is argued that these responses are shaped by the historical development of the legal concept of unique subgroup rights; rights asserted by a subgroup that cannot be asserted by outgroup members or by members of a broader collective that includes all subgroups.
The assertion of unique subgroup rights in contrast to individual rights was studied by presenting participants with scenarios suggestive of human rights violations. These included possible violations of privacy rights of indigenous Australians (Study 1), civil and political rights of indigenous Australians under mandatory sentencing schemes (Study 2), privacy rights of students in comparison to public servants (Study 3), refugee rights (Study 4), and reproductive rights of lesbians and single women in comparison to married women and women in de facto relationships (Study 5). The scenarios were based on real policy issues being debated in Australia at the time of data collection. Human rights activists participated in Studies 4 and 5. In Study 5, these activists participated via an online, web-based experiment. Both quantitative and qualitative data were collected.
A social identity theory perspective is used drawing on concepts from both social identity theory and self-categorization theory. The studies reveal a preference for an equality-driven construal of the purpose of human rights law (i.e. that all Australians be treated equally regardless of subgroup membership) in contrast to minority support for a vulnerable groups construal of the purpose of human rights (i.e. that the purpose of human rights law is to protect vulnerable subgroups within a broader collective).
Tajfelian social belief orientations of social mobility and social change are explicitly measured in Studies 3-5. Consistent with the social identity perspective, these ideological beliefs are conceptualised as background knowledge relevant to the subjective structuring of social reality (violation contexts) and to the process of motivated relative perception from the vantage point of the perceiver. There is some indication from these studies that social belief orientation may determine construals of the purpose of human rights. In Study 5 the observed preference for using inclusive human rights rhetoric in response to perceived subgroup injustice is explained as an identity-management strategy of social creativity. In Studies 4 and 5, explicit measurement of activist identification was also made in an attempt to further explain the apparently-dominant preference for an equality-driven construal of the purpose of human rights law and the preferred use of inclusive, individualised rights rhetoric in response to perceived subgroup injustice.
Activist identification explained some action preferences, but did not simply translate into preferences for using subgroup interest arguments. In Study 5, metastereotyping measures revealed that inclusive rights-based protest strategies were used in order to create positive impressions of social justice campaigners in the minds of both outgroup and ingroup audiences. Ideas for future social psychological research on human rights is discussed.
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少年監獄受刑少年與一般學校班級少年同儕團體之比較研究-社會網路的分析觀點與方法 / A Network Approach to the Explanation of Adolescence Peer Group: A Comparison Study on Juvenile delinquents and School Students.夏蒂蓮, Hsia, Ti Lien Unknown Date (has links)
基於對偏差青少年同儕關係的理論與研究,各家林立,爭論不一,本研究使用社會網路的分析概念與方法,同時比較了偏差青少年與一般青少年同儕關係中的人際吸引、次團體形成、團體感受、團體互動以及個人在團體中態度的相關。企圖對青少年的同儕團體進行較深入的探究,同時亦將同儕關係網路放入個人社會網路中,嘗試瞭解同儕關係在個人社會網路中的位置。
本研究選擇正在新竹少年監獄服刑的一個少年犯班級為受刑少年組,而以台北市景興國中的一個班級為一般少年組。兩者皆為一年級的男生班,前者約有17人,而後者則有44人。為研究人際吸引及班級中次團體的形成過程,本研究採長程貫時的研究設計,為時一學期。
本研究的重要發現如下:
1.誠如青少年幫派的研究,受刑少年組受試者多來自中下階層的家庭。
2.如社會控制理論所預測的,受刑少年組受試者和父母親人的連結關係,大都相當地薄弱。
3.老師關係在兩組樣本的個人人際網路中,都呈現相當低的連結,顯示師生關係有待加強。
4.同儕關係同時在受刑少年組及一般少年組人際網路中佔有重要比例。在一般少年組中,同班同學又為受試者朋友同學關係的重心。但對受刑少年組受試者而言,其要好朋友多為入監前所結識的朋友,其關係較為穩固與密切。
5.受刑少年和一般少年在同儕團體中各著重不同的活動,而受刑少年組在其個人所屬團體中的團體感受(如:支持感、信任感)較一般少年組為佳。顯示社會控制理論對偏差青少年同儕關係的預測須加以修正。
6.從長程貫時的研究設計中,本研究發現隨時間的增加,兩組樣本班級中都有次團體的形成,受刑少年組因班級人數少且相處時間多,較早形成穩定的次團體。
7.比較受刑少年和一般少年次團體的形成,發現在人際吸引過程中,相似性與接近性同時扮演了重要的角色。在受刑少年組中,次團體成員在偏差態度上有相當程度的相似,而相同寢室的受試者亦易形成次團體。就一般少年而言,同一次團體成員除在偏差態度、一般態度與價值觀有較高的相似性外,學業成就的相似性更明顯地影響人際吸引與次團體形成的方向。此外,在一般少年組中座位的接近,亦是次團體形成的重要影響因素。
8.受刑少年在朋友特質所強調的選擇要件上,和一般少年組受試者有明顯地差異。前者偏重選擇「有正義感」的朋友,而後者則重視成續的高低。
9.不論是在受刑少年組或一般少年組中,皆可發現次團體成員擁有較佳的團體感受,而同儕團體中的孤立看則自覺被團體所排斥。
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Statistical Methods for Life History Analysis Involving Latent ProcessesShen, Hua January 2014 (has links)
Incomplete data often arise in the study of life history processes. Examples include missing responses, missing covariates, and unobservable latent processes in addition to right censoring. This thesis is on the development of statistical models and methods to address these problems as they arise in oncology and chronic disease. Methods of estimation and inference in parametric, weakly parametric and semiparametric settings are investigated.
Studies of chronic diseases routinely sample individuals subject to conditions on an event time of interest. In epidemiology, for example, prevalent cohort studies aiming to evaluate risk factors for survival following onset of dementia require subjects to have survived to the point of screening. In clinical trials designed to assess the effect of experimental cancer treatments on survival, patients are required to survive from the time of cancer diagnosis to recruitment. Such conditions yield samples featuring left-truncated event time distributions. Incomplete covariate data often arise in such settings, but standard methods do not deal with the fact that the covariate distribution is also affected by left truncation. We develop a likelihood and algorithm for estimation for dealing with incomplete covariate data in such settings. An expectation-maximization algorithm deals with the left truncation by using the covariate distribution conditional on the selection criterion. An extension to deal with sub-group analyses in clinical trials is described for the case in which the stratification variable is incompletely observed.
In studies of affective disorder, individuals are often observed to experience recurrent symptomatic exacerbations of symptoms warranting hospitalization. Interest lies in modeling the occurrence of such exacerbations over time and identifying associated risk factors to better understand the disease process. In some patients, recurrent exacerbations are temporally clustered following disease onset, but cease to occur after a period of time. We develop a dynamic mover-stayer model in which a canonical binary variable associated with each event indicates whether the underlying disease has resolved. An individual whose disease process has not resolved will experience events following a standard point process model governed by a latent intensity. If and when the disease process resolves, the complete data intensity becomes zero and no further events will arise. An expectation-maximization algorithm is developed for parametric and semiparametric model fitting based on a discrete time dynamic mover-stayer model and a latent intensity-based model of the underlying point process. The method is applied to a motivating dataset from a cohort of individuals with affective disorder experiencing recurrent hospitalization for their mental health disorder.
Interval-censored recurrent event data arise when the event of interest is not readily observed but the cumulative event count can be recorded at periodic assessment times. Extensions on model fitting techniques for the dynamic mover-stayer model are discussed and incorporate interval censoring. The likelihood and algorithm for estimation are developed for piecewise constant baseline rate functions and are shown to yield estimators with small empirical bias in simulation studies. Data on the cumulative number of damaged joints in patients with psoriatic arthritis are analysed to provide an illustrative application.
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Elementos de transposição no gênero Zaprionus (Diptera, Drosophilidae): estudos genômicos e evolutivos em ênfase nos retrotensposons copia, gypsy e micropiaSetta, Nathalia de [UNESP] 06 March 2009 (has links) (PDF)
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setta_n_dr_sjrp.pdf: 1404480 bytes, checksum: e8ca57a6c89dd8308471f12f028ecfe8 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O gênero Zaprionus tem sido eleito como um bom modelo biológico para estudos genéticocomparativos com as espécies do subgrupo melanogaster do gênero Drosophila, embora seu posicionamento filogenético dentro da família Drosophilidae ainda seja controverso. Na presente Tese foi investigada a presença de 10 elementos de transposição (TEs) em Zaprionus indianus e Drosophila malerkotliana, bem como a distribuição, a atividade transcricional e as relações evolutivas de três retrotransposons (copia, gypsy e micropia) em sete espécies do gênero Zaprionus. Para isso, foram empregadas as técnicas de Dot blot, PCR, RT-PCR e seqüenciamento. As seqüências obtidas foram comparadas às dos respectivos elementos das demais espécies de drosofilídeos disponíveis nas bases de dados genômicas. Os resultados indicam que Z. indianus e D. malerkotliana apresentam em seus genomas todos os TEs de D. melanogaster investigados. O retrotransposon copia foi seqüenciado e está transcricionalmente ativo nas sete espécies do gênero Zaprionus e constitui uma nova subfamília relacionada aos elementos do subgrupo melanogaster, que foi denominada subfamília GBFDouble-gap. Por outro lado, os retrotransposons gypsy e micropia foram identificados nas espécies do subgênero Zaprionus, onde também estão transcricionalmente ativos, e pertencem às subfamílias já descritas para as espécies do subgrupo melanogaster. As análises evolutivas sugeriram que esses três retrotransposons devem ter participado de eventos de transferência horizontal com as espécies do subgrupo melanogaster e com pelo menos um doador desconhecido, no caso do retrotransposon micropia. Além disso, o cálculo dos tempos de divergência dos elementos sugere que eles passaram por ondas de transferências horizontais, mais antigas para o retrotransposon copia, e mais recentes para gypsy e micropia. Esses resultados... / The Zaprionus genus has been elected as a good biological model for comparative analyses with the melanogaster subgroup of Drosophila genus, though its phylogenetic positioning within the Drosophilidae family is still controversial. This study aiming at investigating the occurrence of 10 transposable elements (TEs) in Zaprionus indianus and Drosophila malerkotliana species, as well the distribution, transcriptional activity and evolutionary relationships of three retrotransposons (copy, gypsy and micropia) in seven species of Zaprionus genus. To do so, Dot blot, PCR, RT-PCR and sequencing methods were employed. The Zaprionus sequences obtained were compared with the drosophilid sequences available in genomic databases. The results indicated that Z. indianus and D. malerkotliana harbor all D. melanogaster TEs investigated. The copia retrotransposon is present and transcriptionally active in seven species of the Zaprionus genus and represents a new subfamily related to that of the melanogaster subgroup, named as GBFDouble-gap subfamily. Additionally, gypsy and micropia retrotransposons were identified in the Zaprionus species subgenus, which are transcriptionally active and belong to the melanogaster subgroup subfamilies. The evolutionary analysis showed the three retrotransposons could have been involved in horizontal transfer events with species of the melanogaster subgroup for the three retrotransposons and at least one unknown donor regarding to micropia retrotransposon. Moreover, the time of divergence seems to indicate that the retrotransposons experienced horizontal transfer waves, the oldest involving the copia element followed by the gypsy and micropia retrotransposons in more recent times. These results suggest that the horizontal transfer phenomenon has happened repeatedly during the Zaprionus genus and melanogaster subgroup evolution in the Afrotropical region.
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