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Transtorno de déficit de atenção e hiperatividade na vida adulta : estudo sobre o curso e seus moderadores a partir de um seguimento de sete anosKaram, Rafael Gomes January 2014 (has links)
O conhecimento sobre o curso dos transtornos mentais durante a vida e os fatores que influenciam o seu comportamento fazem parte das primeiras informações buscadas por pacientes e por profissionais de saúde, objetivando um melhor planejamento e intervenções mais acuradas. No caso do Transtorno de Déficit de Atenção e Hiperatividade (TDAH), as informações existentes limitam-se a responder sobre o prognóstico do TDAH para amostras de crianças e adolescentes. Estudos longitudinais prospectivos a partir de amostras clínicas de adultos possuem um delineamento capaz de trazer informação sobre o comportamento do TDAH durante a vida adulta. A amostra de Porto Alegre de adultos com TDAH, coletada nos últimos 12 anos no ambulatório de TDAH em adultos do HCPA, possui extensa caracterização em nível fenotípico e genético. O objetivo principal deste trabalho é investigar em pacientes adultos o curso do TDAH e as características sociais e psiquiátricas envolvidas em sua trajetória, sete anos após a avaliação inicial. Para isso, foram realizados dois estudos a fim de observar o comportamento do transtorno e dos seus domínios durante a vida adulta. O primeiro artigo investiga a persistência do diagnóstico formal do TDAH e a possibilidade de remissão completa sete anos após a primeira avaliação. Mesmo após o período de maior neurodesenvolvimento cerebral, e independentemente da idade dos indivíduos, em torno de 30% da amostra perdeu o diagnóstico do transtorno. A remissão completa ocorreu em 12.4% dos pacientes. Indivíduos com diagnóstico de TOD e Fobia Social, maior número de sintomas de hiperatividade/impulsividade e os que se apresentavam no maior quartil de desatenção durante a avaliação inicial persistiram mais frequentemente com o diagnóstico. Nível de prejuízo pelo TDAH, gênero e tempo de uso de metilfenidato não tiveram efeito significativo. No segundo artigo, analisamos separadamente o comportamento dos dois domínios do TDAH e os possíveis moderadores do seu curso, incluindo o efeito de um grupo de sintomas sobre o outro. Diferentemente dos resultados encontrados nos estudos que avaliaram os períodos da infância e adolescência, os sintomas de hiperatividade/impulsividade declinaram na mesma proporção que os de desatenção. A análise dos domínios individualmente também permitiu identificar que cada grupo de sintomas possui moderadores distintos. O declínio dos sintomas de desatenção foi menor nos pacientes com história de suspensão escolar, enquanto que a hiperatividade/impulsividade declinou menos nos indivíduos que possuem história de problemas com álcool e maior número de sintomas de desatenção. A partir dos resultados encontrados e da literatura existente, esta Tese propõe questionamentos sobre variáveis que podem influenciar o curso do TDAH na vida adulta, bem como perspectivas para intervenções preventivas. / A better comprehension regarding the course of mental disorders across the lifespan and the factors that influence its trajectory are among the first goals sought by patients and health professionals in the intent to improve planning and interventions. In the case of Attention Deficit/Hyperactivity Disorder (ADHD), prognosis information is limited to data derived from samples of children and adolescents. Prospective longitudinal studies from clinical samples of adults have the appropriate design to provide information of ADHD trajectory during adulthood. The Porto Alegre sample of adults with ADHD, collected over the past 12 years at the ADHD Outpatient Program – Adult division at the Hospital de Clínicas de Porto Alegre (HCPA), has an extensive phenotypic characterization and genetic level. The main goal of this work is to investigate the course of ADHD, as well as other psychiatric and social characteristics involved in its trajectory, in a sample of adult patients seven years after the initial assessment. For this purpose, two studies were conducted to examine the course of the disorder and its domains during adulthood. The first paper investigates the persistence of formal ADHD diagnosis and the possibility of complete remission seven years after the first evaluation. It shows that, even after the most intense period of brain neurodevelopment, and regardless of the age of the individuals, around 30% of the sample no longer fulfilled the diagnostic criteria for the disorder. Complete remission occurred in 12.4% of patients. Individuals diagnosed with Oppositional Defiant Disorder and Social Phobia, with more symptoms of hyperactivity/impulsivity and those who performed in the top quartile of inattention symptoms during the initial evaluation were more likely to persist with the diagnosis. Level of impairment due to ADHD symptoms, gender and the extent of methylphenidate use (months) had no significant effect. In the second article, the trajectory of the two ADHD domains (inattention and hyperactivity/impulsivity), along with their possible moderators, were analysed separately. Differently from the results found by studies evaluating the course of ADHD domains during childhood and adolescence, this study indicated that symptoms of hyperactivity/impulsivity declined in the same proportion as inattention during adulthood. The analysis of the two ADHD domains separately also identified that each group of symptoms has distinct moderators. The decline of inattention symptoms was lower in patients with a history of school suspension, whereas hyperactivity/impulsivity decline was lower in individuals with a history of problems with alcohol use and more symptoms of inattention. Based on the overall results and the existing literature, this Thesis raises questions about characteristics that may influence the course of ADHD during adulthood, as well as perspectives for preventive interventions.
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Factors Related to Academic Stress and Persistence Decisions of Diné College StudentsJanuary 2018 (has links)
abstract: Native Americans reported the least number of degree completion than any other population in the United States. Native American students experience multiple challenges while in college making them a high-risk population for college departure. This study used two hierarchical multiple regression to explore the relationship between non-cognitive factors (financial concerns, family support for education, cultural involvement, ethnic identity, academic self-efficacy) with both academic stress and academic persistence decisions from a combined sample of 209 Diné college students attending two tribal colleges on the Navajo reservation. Two-week test-retest reliabilities were calculated for three scales: family support for education, financial concerns, and Dine’ cultural involvement. The Multidimensional Inventory of Black Identity Scale was modified to measure two facets of ethnic identity (centrality and private regard) for Diné students. Academic Self-Efficacy was measured by the College Self-Efficacy Inventory. The Daily Hassles Index for College Stress was used to measure academic stress and the Persistence/Voluntary Dropout Decisions Scale was measured academic persistence decisions. Due to its suppression effect on the relation of private regard and academic stress, centrality was not included in the hierarchical regression predicting academic stress; however, it was included in the prediction of academic persistence decisions. Diné students reported high scores for family support for education that suggested that generally the students at Dine’ College perceived that their families as being supportive and encouraging their efforts to get their college degree. In the hierarchical regression predicting academic stress, in step one more cultural involvement and fewer financial concerns predicted less academic stress. In the final model, only fewer financial concerns
and greater academic self-efficacy predicted less academic stress. In the hierarchical regression predicting academic persistence decisions, private regard and academic self- efficacy were significant, positive predictors of persistence decisions. These findings are discussed in light of the role counseling psychologists can play in addressing financial concerns, ethnic identity, and academic self-efficacy among Dine’ students in order to decrease their academic stress and increase their positive decisions about staying in school. / Dissertation/Thesis / Doctoral Dissertation Counseling Psychology 2018
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Mathematical Modeling of Intraguild Predation and its Dynamics in EcologyJanuary 2012 (has links)
abstract: A functioning food web is the basis of a functioning community and ecosystem. Thus, it is important to understand the dynamics that control species behaviors and interactions. Alterations to the fundamental dynamics can prove detrimental to the future success of our environment. Research and analysis focus on the global dynamics involved in intraguild predation (IGP), a three species subsystem involving both competition and predation. A mathematical model is derived using differential equations based on pre-existing models to accurately predict species behavior. Analyses provide sufficient conditions for species persistence and extinction that can be used to explain global dynamics. Dynamics are compared for two separate models, one involving a specialist predator and the second involving a generalist predator, where systems involving a specialist predator are prone to unstable dynamics. Analyses have implications in biological conservation tactics including various methods of prevention and preservation. Simulations are used to compare dynamics between models involving continuous time and those involving discrete time. Furthermore, we derive a semi-discrete model that utilizes both continuous and discrete time series dynamics. Simulations imply that Holling's Type III functional response controls the potential for three species persistence. Complicated dynamics govern the IGP subsystem involving the white-footed mouse, gypsy moth, and oak, and they ultimately cause the synchronized defoliation of forests across the Northeastern United States. Acorn mast seasons occur every 4-5 years, and they occur simultaneously across a vast geographic region due to universal cues. Research confirms that synchronization can be transferred across trophic levels to explain how this IGP system ultimately leads to gypsy moth outbreaks. Geographically referenced data is used to track and slow the spread of gypsy moths further into the United States. Geographic Information Systems (GIS) are used to create visual, readily accessible, displays of trap records, defoliation frequency, and susceptible forest stands. Mathematical models can be used to explain both changes in population densities and geographic movement. Analyses utilizing GIS softwares offer a different, but promising, way of approaching the vast topic of conservation biology. Simulations and maps are produced that can predict the effects of conservation efforts. / Dissertation/Thesis / M.S. Applied Biological Sciences 2012
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Background and Non-cognitive Factors Influencing Academic Persistence Decisions in College FreshmenJanuary 2013 (has links)
abstract: As the retention rate of college freshmen increases, Tinto's (1993) model of academic persistence conceptualizes several dimensions of students' voluntary dropout. This study examined both personal and parental factors that may impact the academic persistence decisions of freshmen college students: 1) parental educational attainment; 2) parental valuing of education; 3) high school grade point average (GPA); 4) residential status (on- versus off-campus); 5) educational self-efficacy; 6) self-esteem; 7) personal valuing of education; 8) perceived academic preparation; and 9) academic expectations. The study sample consisted of 378 freshmen college students at a large southwestern university who were recruited from 23 sections of a 100-level class intended to promote academic success. The participants in this cross-sectional study were restricted to freshman level students and 18 and 19 years old in accordance with Erikson's (1968) Identity stage of psychosocial development. A hierarchical regression analysis revealed that academic persistence decisions were predicted by residential status and self-beliefs, which consisted of: educational self-efficacy, self-esteem, personal valuing of education, perceived academic preparation, and academic expectations. Parental valuing of education was a significant predictor of academic persistence decisions until self-beliefs were added to construct the full model. Although self-beliefs were collectively the most powerful predictors of persistence decisions, accounting for 22.8% of the variance, examination of the beta weights revealed that self-esteem, educational self-efficacy, and personal valuing of education were the most powerful predictors, while academic expectations approached significance. Residential status was also a significant predictor and accounted for a small but significant variance (1.6%) in academic persistence decisions. A significant multivariate difference was found between students living on campus and those living off campus. Follow-up ANOVAs revealed differences in mother's education and in parental valuing of education. These findings suggest that researchers, counselors, and college policy-makers consider on-campus living variables as well as students' self-beliefs when considering academic persistence decisions in college freshmen. / Dissertation/Thesis / M.C. Counseling 2013
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Is It Really Up To Me? Academic and Life Tensions for "Double First-Generation" College StudentsJanuary 2013 (has links)
abstract: This study examined the experiences of first-generation college students who were enrolled in online degree programs at a traditional brick-and-mortar university located in the western United States. These students were viewed as "double first-generation" because they were not only the first in their family to pursue a bachelor's degree, but were also among the first generation in the history of American higher education to pursue public, postsecondary education in an entirely online format. The research was designed as a multiple methods case study that emphasized qualitative methods. Being exploratory in nature, the study focused on participant characteristics and the ways that they responded to and persisted in online degree programs. Data was collected through research that was conducted entirely online; it included an e-survey, two asynchronous focus groups, and individual interviews that were conducted via Skype. Grounded theory served as the primary method for data analysis, while quantitative descriptive statistics contextualized the case. The results of this study provide a window into the micro- and macro-level tensions at play in public, online postsecondary education. The findings indicate that these pioneering and traditionally underserved students drew from their diverse backgrounds to persist toward degree completion, overcoming challenges associated with time and finances, in hopes that their efforts would bring career and social mobility. As one of the first studies to critically examine the case of double first-generation college students, this study extends the literature in meaningful ways to provide valuable insights for policymakers, administrators, faculty, and staff who are involved with this population. / Dissertation/Thesis / Ph.D. Educational Leadership and Policy Studies 2013
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A New Backoff Strategy Using Topological Persistence In Wireless NetworksJanuary 2013 (has links)
abstract: Contention based IEEE 802.11MAC uses the binary exponential backoff algorithm (BEB) for the contention resolution. The protocol suffers poor performance in the heavily loaded networks and MANETs, high collision rate and packet drops, probabilistic delay guarantees, and unfairness. Many backoff strategies were proposed to improve the performance of IEEE 802.11 but all ignore the network topology and demand. Persistence is defined as the fraction of time a node is allowed to transmit, when this allowance should take into account topology and load, it is topology and load aware persistence (TLA). We develop a relation between contention window size and the TLA-persistence. We implement a new backoff strategy where the TLA-persistence is defined as the lexicographic max-min channel allocation. We use a centralized algorithm to calculate each node's TLApersistence and then convert it into a contention window size. The new backoff strategy is evaluated in simulation, comparing with that of the IEEE 802.11 using BEB. In most of the static scenarios like exposed terminal, flow in the middle, star topology, and heavy loaded multi-hop networks and in MANETs, through the simulation study, we show that the new backoff strategy achieves higher overall average throughput as compared to that of the IEEE 802.11 using BEB. / Dissertation/Thesis / M.S. Computer Science 2013
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Determining Persistence of Community College Students in Introductory Geology ClassesJanuary 2014 (has links)
abstract: Science, Technology, Engineering & Mathematics (STEM) careers have been touted as critical to the success of our nation and also provide important opportunities for access and equity of underrepresented minorities (URM's). Community colleges serve a diverse population and a large number of undergraduates currently enrolled in college, they are well situated to help address the increasing STEM workforce demands. Geoscience is a discipline that draws great interest, but has very low representation of URM's as majors. What factors influence a student's decision to major in the geosciences and are community college students different from research universities in what factors influence these decisions? Through a survey-design mixed with classroom observations, structural equation model was employed to predict a student's intent to persist in introductory geology based on student expectancy for success in their geology class, math self-concept, and interest in the content. A measure of classroom pedagogy was also used to determine if instructor played a role in predicting student intent to persist. The targeted population was introductory geology students participating in the Geoscience Affective Research NETwork (GARNET) project, a national sampling of students in enrolled in introductory geology courses. Results from SEM analysis indicated that interest was the primary predictor in a students intent to persist in the geosciences for both community college and research university students. In addition, self-efficacy appeared to be mediated by interest within these models. Classroom pedagogy impacted how much interest was needed to predict intent to persist, in which as classrooms became more student centered, less interest was required to predict intent to persist. Lastly, math self-concept did not predict student intent to persist in the geosciences, however, it did share variance with self-efficacy and control of learning beliefs, indicating it may play a moderating effect on student interest and self-efficacy. Implications of this work are that while community college students and research university students are different in demographics and content preparation, student-centered instruction continues to be the best way to support student's interest in the sciences. Future work includes examining how math self-concept may play a role in longitudinal persistence in the geosciences. / Dissertation/Thesis / Ph.D. Curriculum and Instruction 2014
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Etude des facteurs viraux et cellulaires impliqués dans l'échappement du virus de l'hépatite C au cours de la transplantation hépatique / Study of viral and cellular factors involved in hepatitis C virus escape during liver transplantationFauvelle, Catherine 02 December 2013 (has links)
La cirrhose et le carcinome hépatocellulaire liés au virus de l’hépatite C (HCV) sont des indications majeures de transplantation hépatique. La réinfection du greffon par le HCV est systématique et sans moyen de prévention. Les mécanismes par lesquels le virus échappe au système immunitaire afin de réinfecter le greffon sont mal connus. Ce travail de thèse a permis d’identifier de nouveaux mécanismes et des déterminants clés impliqués dans la persistance virale. Nous avons identifié que l’utilisation des facteurs d’entrée cellulaires par le HCV évolue simultanément avec ses capacités d’échappement aux nAbs, et démontré qu’apo E est un composant clé des lipoparticules virales intervenant dans la persistance du HCV. L’identification de nouveaux facteurs viraux et cellulaires impliqués dans l’échappement viral, apporte de nouvelles perspectives dans le développement de nouvelles stratégies de prévention de la réinfection ainsi que dans le développement d’un vaccin prophylactique. / Hepatitis C virus (HCV)-cirrhosis and HCC are leading indications for liver transplantation. Reinfection of the liver graft is universal and no way of prevention exists. Mechanisms employed by HCV to evade the immune system and reinfect the liver graft are unknown. This thesis work identified new mechanisms and key determinants involved in viral persistence. Weidentified a novel clinically and therapeutically important mechanism of viral evasion, where coevolution simultaneously occurs between cellular entry factor use and escape from neutralization. We also discovered that virus-apoE interaction is unique mechanism of viral evasion from neutralizing antibodies. Identification of new viral and host factors involved in viral escape paves the way in the development of new prevention strategies and prophylactic vaccine.
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Infecção por rinovírus em células linfoides de tonsilas humanas / Rhinovirus infection in lymphoid tissues from hypertrophic human tonsilsRonaldo Bragança Martins Junior 11 May 2017 (has links)
Rinovírus (RV) é freqüentemente detectado nos tecidos tonsilares e nas secreções de nasofaringe de pacientes com doença adenotonsilar crônica, sem sintomas de infecção respiratória aguda (IRA). O objetivo deste estudo foi investigar a infecção por rinovírus em tonsilas humanas, com base em dois aspectos: infecção in vivo de células linfóides de tonsilas humanas naturalmente infectadas; e infecção ex vivo de células dissociadas desses tecidos inoculadas com rinovírus, visando a contribuir para elucidar possíveis mecanismos de infecção em amígdalas palatinas e adenóides humanas. De um total de 104 pacientes com doenças adenotonsilar crônicas, 21.1% (22/104) e 42.3% (44/104) apresentaram respectivamente amígdalas palatinas e adenóides positivas para RV por PCR. A replicação viral foi confirmada por hibridização in situ com sonda para intermediário replicativo nas regiões internas e externas aos folículos linfóides de amígdalas e adenóides, bem como em porções do epitélio ciliado de adenoides, e apenas raramente nas células epiteliais escamosas de tonsilas palatinas. A presença e distribuição de proteína estrutural do capsídeo viral foi detectada por imunohistoquímica (IHQ), utilizando anticorpos contra proteínas estruturais virais VP1 e VP2 nas tonsilas positivas para RV por qPCR. Os resultados indicaram marcação positiva tanto na superfície (epitélio), quanto em regiões extrafoliculares e centros germinativos. Em seguida, foi possível verificar a co-localização da marcação positiva da proteína estrutural VP2 de RV com marcadores linfocitários de membrana. Células CD4 + e CD20 + apresentaram marcação positiva para VP2 verificada usando estratégia de \'sequential immuno-peroxidase labelling and erasing\' (SIMPLE). Culturas primárias de células linfomononucleares (CLMN) de tonsilas sabidamente negativas para RV por PCR, foram infectadas in vitro, com RV (MOI=1). A replicação de RV foi titulada por TCID50, mostrando aumento inicial (24 h) e subsequente queda após 48 horas. Por IF observamos que os fenótipos de CLMN infectadas com RV in vitro foram células T CD4 + e B, mas também com células CD8 +, CD56 + e CD33 +. RV não infectou células CD123 +. RV foi isolado em WI- 38 e HeLa a partir de tecidos e secreções de nasofaringe de pacientes com hipertrofia tonsilar sem sintomas de infecção respiratória aguda. Nossos resultados confirmam que tonsilas de pacientes sem sintomas respiratórios agudos podem ser reservatórios de RV, que infecta não somente epitélio, mas também CLMN (frequentemente linfócitos T CD4 + e linfócitos B). A detecção de RNA intermediário replicativo e proteínas estruturais VP1 e VP2 nas tonsilas hipertróficas, além do isolamento de vírus infeccioso a partir de tecidos e secreções nasofaríngeas, classificam tonsilas hipertróficas como sítios de infecção e replicação de RV, e sugerem que esses indivíduos hipertróficos são portadores assintomáticos de RV persistente, e podem ser importantes fontes de transmissão de RV na comunidade. / The chronic adenotonsillar diseases are frequent otorhinolaryngologic conditions caused by chronic inflammation of adenoids and palatine tonsils. Rhinovirus (RV) is highly frequently detected in secretions, and tonsillar tissues from patients experience chronic tonsillar hypertrophy without symptoms of ARI, and our goal is to full understanding of viral infections in hypertrophic tonsillar tissues by RV. Of 104 enrolled patients with adenotonsillar chronic diseases, 21.1% (22/104) and 42.3% (44/104) had palatine tonsils and adenoids positive for RV by qPCR, respectively. RV Viral replication was confirmed by in situ hybridizations. Minus-strand RNA were detected in all tested samples (7 tonsils and 9 adenoids), and positive reactions were seen inside and outside of lymphoid follicles from tonsils and adenoids, in the ciliated epithelium of the adenoids and rarely in positive squamous epithelium cells from tonsils. The presence of viral structural protein VP1 and VP2 was detected within and outside of the lymphoid follicles from tonsils and adenoids, and also in epithelial cells from adenoids by immunohistochemistry (IHC). Later, by sequential immuno-peroxidase labelling and erasing protocol (SIMPLE), we saw co-localization of RV VP2 capsid protein staining with CD4 positive cells and CD20 positive cells. We confirmed that RV could infect primary culture of tonsilar mononuclear cells (TMNCs). Additionally, intracellular replication of RV in TMNCs, measured by TCID50 in HeLa cells, had an initial increase in the first 24 hours, and dropped at 48 hours post infection. Immunolocalization staining with anti-RV and TMNCs surface markers indicated that phenotypes of susceptible cells were T-cells both CD4+ and CD20+, but also, we saw co-localization of VP-2 protein with CD8+ cells, CD56+ cells and CD33+ cells. RV-16 couldn\'t infect CD123+ cell in our experiments. Finally, we were able to recover 4 rhinoviruses by inoculating WI-38 fibroblast cells and HeLa cells, confirming by the cytopathic effect and immunofluorescence positive staining with anti-VP1 antibody. Taken together, our results indicate that tonsils and adenoids of patients without ARI may be reservoirs of replicating human rhinovirus, infecting manly Tcells CD4+ and CD20+ B-cells. The high-frequency detection of RNA (-) and VP1 expression in tissues from patients with chronic adenotonsillar diseases, plus the isolation of infectious viral particles, suggests that these detected agents replicate in the adenotonsillar tissues and this specific sites may be important sources of transmission of RV in the community.
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MD-JPA : um perfil UML para modelagem do mapeamento objeto-relacional com JPA em uma abordagem dirigida por modelos / MD-JPA:a UML profile for object relational mapping with JPA in a model driven approachTorres, Alexandre January 2009 (has links)
A abordagem de desenvolvimento dirigido por modelos (DDM) propõe que modelos (e transformações entre modelos) assumam o papel principal no desenvolvimento de sistemas. Entretanto, não há uma notação consensual para modelagem de persistência baseada em arcabouços de mapeamento objeto-relacional: enquanto a UML não possui recursos específicos para a modelagem de persistência, o modelo entidade-relacionamento não expressa os conceitos dinâmicos existentes na UML. Este trabalho propõe o perfil UML MD-JPA (Model Driven JPA) para a modelagem de persistência baseada na já difundida API de persistência Java (JPA), buscando a modelagem dos elementos persistentes e transientes de forma mais coerente e integrada. São especificadas as principais características do perfil MD-JPA, assim como a maneira pela qual modelos que adotam este perfil podem ser transformados em implementação Java, através de transformações de modelos propostas em uma abordagem DDM. Por fim, uma ferramenta de código livre foi desenvolvida para disponibilizar para comunidade os resultados deste trabalho. / The model driven development (MDD) approach proposes that models (and modelto- model transformations) play the main role on system development. However, there is not a consensual notation to model persistence based upon object relational mapping frameworks: while UML lacks specific resources for persistence modeling, the entityrelationship model does not make reference to the dynamic concepts existing in UML. This work proposes MD-JPA, a UML profile for persistence modeling based on the well-known Java Persistence API (JPA), pursuing the modeling of transient and persistent elements in a more coherent and integrated way. This work describes the main characteristics of MD-JPA as well as the way that models that adopt such profile can them be used to generate a Java implementation by the application of the proposed model transformations on a MDD approach. Finally, an open source tool was developed to make the results of this work available to the community.
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