The current global and data intensive outlook of research provides new opportunities and challenges for HEIs including effective and sustainable RDM. As a growing area of interest in the global research arena, experiences from developed countries have dominated the body of literature on RDM. This study is in part, to fill this gap by assessing the state of the art of RDM and institutional preparedness at the University of Ghana (through existing data management activities and capabilities) in order to develop a plan for implementation. The study used a qualitative case study method and gathered data using semi-structured interviews and document analysis. Thematic analysis method was used to analyse the data collected. A total of seven respondents (five service providers and two senior researchers) were selected purposively using two sampling techniques ("priori criteria sampling" and snowball sampling). Criteria were set for their inclusion and each respondent provided information about institutional support, capabilities, policies and expectations on RDM. The findings of the study revealed a number of RDM related activities, these include support for collaborative research, support for data analysis and computational science, guidance on RDM and grant applications as well as support for storage and high-speed connectivity to facility the research enterprise at UG. In terms of capabilities, no specific RDM policy was identified, existing infrastructure identified include an HPC cluster, a private cloud facility (HP Cloud Matrix), an Institutional repository (UGSpace), an institutional Google Drive platform, data analysis packages (NVivo and SPSS) and a robust network and security infrastructure. These were not necessarily provisioned for RDM purposes. Also, the findings show that staff do not possess the necessary skills or adequate knowledge to fully support RDM at UG. In terms of the specific objectives of the study, the results of the semi-structured interviews and document analysis provided an understanding of the current situation (i.e. requirements, current activities and capabilities at the UG) which is the first objective of the study. These findings were then benchmarked against the EPSRC policy framework following the outline of the DCC CARDIO Matrix and using the optimal desirable expectation or level of development as the standard for comparison. This was useful in identifying gaps in RDM awareness, support and capabilities at UG which is the second objective of the study. To achieve the third objective, which was identifying priority areas for RDM development, the researcher examined both initial findings (i.e. findings on requirements, current activities and capabilities identified under the first objective as well as the gaps identified in the second objective) and proposed six broad areas where UG must focus its RDM development agenda. Finally, the six broad areas proposed in objective three were further cascaded into a number of specific initiatives and tasks to be implemented. This was done taking cognisance of the potential of current infrastructure, gaps identified in institutional awareness and capabilities as well as essentials for a cultural changed. The study concluded that RDM at the University of Ghana is currently underdeveloped but with immense potential for growth. While a few RDM related activities were identified, existing capabilities were generally found to be inchoate, uncoordinated and not formally instituted. The study recommended six main areas where the UG should focus RDM development, these include: constituting a steering group to spearhead and coordinate RDM development at the UG, developing a coordinated policy framework for RDM at UG, streamlining existing technical infrastructure to support data management requirements, creating opportunities for RDM training and capacity development for professional staff, researchers and students, developing services to support requirements, and exploring internal funding strategies to facilitate RDM development and support at the UG. The study also recommends that the academic community at the UG should be actively engaged throughout the RDM development process as this is critical to ensure that the eventual solutions are fit for purpose and acceptable. / Mini Dissertation (MIT)--University of Pretoria, 2016. / Information Science / MIT / Unrestricted

Research Data Management (RDM) has received a lot of attention recently. In South Africa, the importance of RDM has amplified since the release of the National Research Foundation‟s (NRF) open access statement. According to the statement, researchers who receive funding from the NRF must deposit their research output in an open access (OA) repository. In addition, the data supporting the research should be deposited in an accredited OA repository with a Digital Object Identifier (DOI) for future citations (NRF, 2015: online). The mandate, along with other drivers such as research data re-use, increased impact and validation of research findings has forced institutions to investigate the possibility of offering RDM services in their institutions (Ashley, 2012). It is expected that libraries and Library and Information Science (LIS) professionals will initiate and support RDM in their institutions. LIS professionals will need to upgrade or obtain new skills and knowledge to fulfil their new roles and responsibilities. Various training opportunities are available to interested professionals to improve their knowledge and skills related to RDM. These can be as simple as a workshop or as complex as a university degree. The objective of this research was to identify and evaluate a RDM training intervention to determine whether the training intervention could enhance the knowledge and skills of LIS professionals in South African (SA) Higher Education Institutions (HEIs). An embedded research design was used to investigate whether an RDM workshop, hosted by the Network for Data and Information Curation Communities (NeDICC), could enhance the LIS professional‟s (participants) perception of their RDM understanding, knowledge and skills. The research found that the RDM workshop was highly successful in enhancing the participant‟s perception of their RDM understanding and knowledge. The RDM workshop was less successful in enhancing the participant‟s perception of their RDM skills. It was recommended that LIS professionals (1) take advantage of the online RDM training material available to enhance their understanding and knowledge of RDM; (2) attend face-to-face training interventions to enhance or develop their RDM skills and (3) enrol in university level educational programmes to gain a qualification in RDM if they qualify. It was also recommended that institutions that provide RDM training should focus on specific aspects of RDM instead of offering a general overview. This research can be used to inspire larger studies or studies that compare two or more RDM training interventions. / Mini Dissertation (MIT)--University of Pretoria, 2016. / Carnegie Corporation of New York / University of Pretoria / Information Science / MIT / Unrestricted

The advances in additive manufacturing removed most of the limitations that were once stopping designers when it comes to the manufacturability of the design. It allowed designers to produce parts with high geometric complexity such as cellular structures. These structures are known for their high strength relative to their low mass, good energy absorption, and high thermal and acoustic insulation compared to their relative solid counter-parts. Lattice structures, a type of cellular structures, have received considerable attention due to their properties when producing light-weight with high strength parts. The design of these structures can pose a challenge to designers due to the sheer number of variables that are present. Traditional optimization approaches become an infeasible approach for designing them, which motivated researchers to search for other alternative approaches. In this research, a new method is proposed by utilizing the material density information obtained from the topology optimization of continuum structures. The efficacy of the developed method will be compared to existing methods, such as the Size Matching and Scaling (SMS) method that combines solid-body analysis and a predefined unit-cell library. The proposed method shows good potential in structures that are subjected to multiple loading conditions compared to SMS, which would be advantageous in creating reliable structures. In order to demonstrate the applicability of the proposed method to practical engineering applications, the design problem of a commercial elevator sling will be considered.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-14T20:19:26Z No. of bitstreams: 1 EriemAllyneMedeirosAzevedo_DISSERT.pdf: 6333576 bytes, checksum: 4fb198cb10ff3117dbd15b989910b143 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-15T23:30:13Z (GMT) No. of bitstreams: 1 EriemAllyneMedeirosAzevedo_DISSERT.pdf: 6333576 bytes, checksum: 4fb198cb10ff3117dbd15b989910b143 (MD5) / Made available in DSpace on 2016-06-15T23:30:13Z (GMT). No. of bitstreams: 1 EriemAllyneMedeirosAzevedo_DISSERT.pdf: 6333576 bytes, checksum: 4fb198cb10ff3117dbd15b989910b143 (MD5) Previous issue date: 2015-12-17 / Embora que eficiente do ponto de vista t?cnico, as camadas de argamassa que constituem o revestimento tradicional de alvenaria (chapisco, embo?o e reboco) apresentam-se em contradi??o com as novas tecnologias construtivas e m?todos mais eficientes de consumo e racionaliza??o da obra. Do ponto de vista ambiental, o aproveitamento de res?duos em novos comp?sitos para a constru??o civil tem sido uma vertente de estudos em crescimento na comunidade cient?fica, podendo vir a ser uma solu??o econ?mica, em alguns casos. Assim sendo, essa pesquisa prop?e o desenvolvimento de uma argamassa para Revestimento Decorativo Monocamada (RDM), para aplica??o em fachadas, produzida em canteiro, incorporando res?duo de vidro temperado (RVT) na matriz ciment?cia, como substituto parcial do agregado. Para tanto, adotou-se a rela??o aglomerante/agregado de 1:6 (em volume), ?ndice de consist?ncia de 250mm ? 20, teores de substitui??o da areia por res?duo de vidro em 20%, 50% e 80%, e rela??o ?gua/cimento vari?vel em diversos tra?os. Foram utilizados dois aditivos, um polim?rico, ? base de estireno butadieno, e outro qu?mico, al?m da adi??o mineral de s?lica ativa e de pigmento inorg?nico nas cores vermelho, amarelo e azul. Foram realizados ensaios mec?nicos para a massa no estado fresco e endurecido, assim como para o revestimento aplicado sobre alvenaria, de modo a demonstrar a viabilidade do material. Al?m disso, verificou-se a adequabilidade do RDM ao ambiente constru?do, por meio de ensaios t?rmicos. Os resultados demonstram a exequibilidade do RDM proposto com valores expressivamente superiores, quando comparado ?s normatiza??es. Assim sendo, o estudo apresenta-se a comunidade cient?fica como um incentivo ao uso das inova??es tecnol?gicas na constru??o, aumentando o leque de alternativas dispon?veis para a produ??o habitacional, com a proposi??o de um material que alcan?a as funcionalidades pretendidas e obt?m ganho ambiental, podendo ser adotado em canteiros de obras, em contrapartida as argamassas industrializadas. / Although efficient from a technical point of view, mortar layers that make up the traditional masonry coating (slurry mortar, plaster and plaster) have to be in contradiction with the new construction technologies and more efficient methods of consumption and work rationalization. From an environmental point of view, the recovery of waste into new composites for the building has been a growing strand of studies in the scientific community, may prove to be a cost-effective solution in some cases. Thus, this research proposes the development of a mortar Decorative Coating Monolayer (RDM), for use in facades, produced on site, incorporating tempered glass waste (RVT) in the cement matrix, as a partial substitute for aggregate. Therefore, we adopted the binder respect / aggregate of 1: 6 (by volume), consistency index 250mm ? 20, sand substitution levels of glass waste 20%, 50% and 80% and relative water / cement varied in many traits. Two additives were used, a polymer, styrene-butadiene-based, and other chemical, besides mineral and silica fume inorganic pigment in colors red, yellow and blue. Mechanical tests were carried out on fresh pasta and hardened, as well as for the applied coating on masonry, so as to demonstrate the feasibility of the material. In addition, it verified the adequacy of the RDM built environment by means of thermal tests. The results demonstrated the feasibility of the proposed RDM with significantly higher values when compared to norms, especially the dash-added replacement content of 20% and addition of pigment in red. Therefore, the study shows the scientific community as an incentive to the use of technological innovations in construction, increasing the range of alternatives available for housing production, with the proposition of a material that achieves the desired functionality and obtain environmental gain, and may be adopted on construction sites as an alternative industrialized mortars.

Management of research data is globally being seen as part of good research practice. As a result of this, funders are increasingly insisting on proof of good research data management (RDM) practices when funding proposals are submitted. This study aimed at establishing the data management practices of emerging researchers at the Council for Scientific and Industrial Research (CSIR), South Africa. With no official RDM procedures currently being implemented at the CSIR, it was hoped that by gaining information about the RDM practices of emerging CSIR researchers, as well as insight into the RDM challenges experienced by them, this researcher would be able to put forward recommendations enabling the establishing of an RDM regime at the CSIR. The study aimed at answering several research questions. The main research question was: How can an organisation like the CSIR ensure that future researchers apply best practices when managing the CSIR’s research data? Five research sub-questions were identified: 1. What are the international RDM requirements, standards, best practices and expectations that are being developed? 2. What data practices need more formalised support: at CSIR, nationally, internationally? 3. What data are collected and held by emerging researchers in the CSIR? 4. What are the current RDM practices and themes among emerging researchers in the CSIR? 5. What are the RDM-related challenges, issues and concerns facing emerging researchers at the CSIR? A total of 48 emerging researchers from the Council for Scientific and Industrial Research (CSIR), South Africa completed an online survey investigating their RDM practices. RDM practices investigated included the use of data management plans, data storage and backup locations, creation of metadata, metadata standard adherence, and data sharing practices. Challenges faced when managing research data, as well as RDM needs and requirements, also formed part of the survey. Results of the online questionnaire revealed that the RDM practices of the group studied do not show to differ significantly from experienced CSIR researchers, or from researchers studied elsewhere on the globe. Findings enabled this researcher to put forward several recommendations which would assist in the implementing of a formalised RDM structure at the CSIR. Recommendations addressed, but were not limited to: formalization of RDM procedures, RDM marketing, and RDM training. / Dissertation (MIS)--University of Pretoria, 2016. / Information Science / MIS / Unrestricted

Because of the importance of Research Data Management (RDM) in the life sciences, where vast amounts of research data in different complex formats are being produced, this study aimed to assess the state of RDM readiness in the life sciences at Wits to ascertain what support is needed with regards to RDM. In order to achieve the aim, the current RDM practices and needs of researchers, as well as the challenges they face, were investigated. The Jisc Research Data Lifecycle (Jisc, 2021a) was used to guide the literature review, frame data collection, analyse data and advise on some of the main findings and recommendations. A mixed methods approach and an explanatory sequential design were used to achieve the research objectives. For the quantitative phase of research, an online questionnaire was used to collect data. As the total target population (282) was not big, a census was conducted. The questionnaire was administered using SurveyMonkey software. During the qualitative part of the research, semi-structured interviews were used to explain the quantitative results. Five participants were purposively sampled to take part in interviews. The statistical package, MS Excel, was used to analyse quantitative data whilst qualitative data were analysed by thematic analysis. The study showed that life sciences researchers at Wits have adopted many RDM practices, and researchers are increasingly becoming aware of the importance of the openness of data. However, they are dealing with similar RDM issues as their peers worldwide. Results highlighted challenges of, amongst others, the lack of an RDM policy as well as the lack of, or unawareness of, appropriate RDM training and support at Wits. As formal implementation of RDM still needs to take place at Wits, it is recommended that Wits puts an RDM policy in place, followed by suitable RDM infrastructure and awareness making of current services.

The aim of the study was to compile a conceptual model of a Virtual Research Environment (VRE) that indicates the relationship between Research Data Management (RDM) and VREs. The outcome of this study was that VREs are ideal platforms for the management of research data. In the first part of the study, a literature review was conducted by focusing on four themes: VREs and other concepts related to VREs; VRE components and tools; RDM; and the relationship between VREs and RDM. The first theme included a discussion of definitions of concepts, approaches to VREs, their development, aims, characteristics, similarities and differences of concepts, an overview of the e-Research approaches followed in this study, as well as an overview of concepts used in this study. The second theme consisted of an overview of developments of VREs in four countries (United Kingdom, USA, The Netherlands, and Germany), an indication of the differences and similarities of these programmes, and a discussion on the concept of research lifecycles, as well as VRE components. These components were then matched with possible tools, as well as to research lifecycle stages, which led to the development of a first conceptual VRE framework. The third theme included an overview of the definitions of the concepts ‘data’ and ‘research data’, as well as RDM and related concepts, an investigation of international developments with regards to RDM, an overview of the differences and similarities of approaches followed internationally, and a discussion of RDM developments in South Africa. This was followed by a discussion of the concept ‘research data lifecycles’, their various stages, corresponding processes and the roles various stakeholders can play in each stage. The fourth theme consisted of a discussion of the relationship between research lifecycles and research data lifecycles, a discussion on the role of RDM as a component within a VRE, the management of research data by means of a VRE, as well as the presentation of a possible conceptual model for the management of research data by means of a VRE. This literature review was conducted as a background and basis for this study. In the second part of the study, the research methodology was outlined. The chosen methodology entailed a non-empirical part consisting of a literature study, and an empirical part consisting of two case studies from a South African University. The two case studies were specifically chosen because each used different methods in conducting research. The one case study used natural science oriented data and laboratory/experimental methods, and the other, human orientated data and survey instruments. The proposed conceptual model derived from the literature study was assessed through these case studies and feedback received was used to modify and/or enhance the conceptual model. The contribution of this study lies primarily in the presentation of a conceptual VRE model with distinct component layers and generic components, which can be used as technological and collaborative frameworks for the successful management of research data. / Thesis (DPhil)--University of Pretoria, 2018. / National Research Foundation / Information Science / DPhil / Unrestricted

Das hier vorliegende Handbuch ist im Rahmen des Projektes „Vernetztes Forschungsdatenmanagement an Hochschulen für angewandte Wissenschaften am Beispiel der HTW Dresden – FoDaMa-HTWD“ entstanden.1 Es stellt eine kurze und übersichtliche Zusammenfassung der wichtigsten Erkenntnisse dar, welche während der Projektlaufzeit an der Hochschule für Technik und Wirtschaft Dresden (HTWD) zum Forschungsdatenmanagement (FDM) gewonnen wurden. Die Autor/innen möchten mit diesem Handbuch andere Hochschulen für angewandte Wissenschaften (HAW) bei der Strategieentwicklung und dem notwendigen FDM-Strukturaufbau unterstützen. Es richtet sich demnach vorrangig an Personen, die sich an Hochschulen mit der strategischen Weiterentwicklung im Bereich Forschung beschäftigen und sich vielleicht die Frage stellen, welche unterstützenden FDM-Services und Maßnahmen ergriffen werden sollten, damit die Forschenden der eigenen Institution der zunehmenden Forderung nach offener und nachhaltiger Arbeitsweise im Umgang mit Forschungsdaten gerecht werden können. / This handbook was developed within the project ' Vernetztes Forschungsdatenmanagement an Hochschulen für angewandte Wissenschaften am Beispiel der HTW Dresden – FoDaMa-HTWD '. It is a short and clear summary of the most important findings, which were gained during the project at the University of Applied Sciences Dresden (HTWD) on research data management (FDM). With this handbook, the authors would like to support other Universities of Applied Sciences (HAW) in developing strategies and the necessary FDM structure. It is therefore primarily aimed at people who are involved in the strategic development of research at universities and who may ask themselves the question of which supporting FDM services and measures should be taken to ensure that the researchers of their own institution are able to meet the increasing demand for open and sustainable working methods in dealing with research data.

L’hypothyroïdie congénitale par dysgénésie thyroïdienne (HCDT) est la condition endocrinienne néonatale la plus fréquemment rencontrée, avec une incidence d’un cas sur 4000 naissances vivantes. L’HCDT comprend toutes les anomalies du développement de la thyroïde. Parmi ces anomalies, le diagnostic le plus fréquent est l’ectopie thyroïdienne (~ 50% des cas). L’HCDT est fréquemment associée à un déficit sévère en hormones thyroïdiennes (hypothyroïdisme) pouvant conduire à un retard mental sévère si non traitée. Le programme de dépistage néonatal assure un diagnostic et un traitement précoce par hormones thyroïdiennes. Cependant, même avec un traitement précoce (en moyenne à 9 jours de vie), un retard de développement est toujours observé, surtout dans les cas les plus sévères (c.-à-d., perte de 10 points de QI). Bien que des cas familiaux soient rapportés (2% des cas), l’HCTD est essentiellement considérée comme une entité sporadique. De plus, plus de 92% des jumeaux monozygotiques sont discordants pour les dysgénésies thyroïdiennes et une prédominance féminine est rapportée (spécialement dans le cas d’ectopies thyroïdiennes), ces deux observations étant clairement incompatible avec un mode de transmission héréditaire mendélien. Il est donc cohérent de constater que des mutations germinales dans les facteurs de transcription thyroïdiens connus (NKX2.1, PAX8, FOXE1, and NKX2.5) ont été identifiées dans seulement 3% des cas sporadiques testés et furent, de plus, exclues lors d’analyse d’association dans certaines familles multiplex. Collectivement, ces données suggèrent que des mécanismes non mendéliens sont à l’origine de la majorité des cas de dysgénésie thyroïdienne. Parmi ces mécanismes, nous devons considérer des modifications épigénétiques, des mutations somatiques précoces (au stade du bourgeon thyroïdien lors des premiers stades de l’embryogenèse) ou des défauts développementaux stochastiques (c.-à-d., accumulation aléatoire de mutations germinales ou somatiques). Voilà pourquoi nous proposons un modèle «2 hits » combinant des mutations (épi)génétiques germinales et somatiques; ce modèle étant compatible avec le manque de transmission familial observé dans la majorité des cas d’HCDT. Dans cette thèse, nous avons déterminé si des variations somatiques (épi)génétiques sont associées à l’HCTD via une approche génomique et une approche gène candidat. Notre approche génomique a révélé que les thyroïdes ectopiques ont un profil d’expression différent des thyroïdes eutopiques (contrôles) et que ce profil d’expression est enrichi en gènes de la voie de signalisation Wnt. La voie des Wnt est cruciale pour la migration cellulaire et pour le développement de plusieurs organes dérivés de l’endoderme (p.ex. le pancréas). De plus, le rôle de la voie des Wnt dans la morphogénèse thyroïdienne est supporté par de récentes études sur le poisson-zèbre qui montrent des anomalies du développement thyroïdien lors de la perturbation de la voie des Wnt durant différentes étapes de l’organogénèse. Par conséquent, l’implication de la voie des Wnt dans l’étiologie de la dysgénésie thyroïdienne est biologiquement plausible. Une trouvaille inattendue de notre approche génomique fut de constater que la calcitonine était exprimée autant dans les thyroïdes ectopiques que dans les thyroïdes eutopiques (contrôles). Cette trouvaille remet en doute un dogme de l’embryologie de la thyroïde voulant que les cellules sécrétant la calcitonine (cellules C) proviennent exclusivement d’une structure extrathyroïdienne (les corps ultimobranchiaux) fusionnant seulement avec la thyroïde en fin de développement, lorsque la thyroïde a atteint son emplacement anatomique définitif. Notre approche gène candidat ne démontra aucune différence épigénétique (c.-à-d. de profil de méthylation) entre thyroïdes ectopiques et eutopiques, mais elle révéla la présence d’une région différentiellement méthylée (RDM) entre thyroïdes et leucocytes dans le promoteur de FOXE1. Le rôle crucial de FOXE1 dans la migration thyroïdienne lors du développement est connu et démontré dans le modèle murin. Nous avons démontré in vivo et in vitro que le statut de méthylation de cette RDM est corrélé avec l’expression de FOXE1 dans les tissus non tumoraux (c.-à-d., thyroïdes et leucocytes). Fort de ces résultats et sachant que les RDMs sont de potentiels points chauds de variations (épi)génétiques, nous avons lancé une étude cas-contrôles afin de déterminer si des variants génétiques rares localisés dans cette RDM sont associés à la dysgénésie thyroïdienne. Tous ces résultats générés lors de mes études doctorales ont dévoilé de nouveaux mécanismes pouvant expliquer la pathogenèse de la dysgénésie thyroïdienne, condition dont l’étiologie reste toujours une énigme. Ces résultats ouvrent aussi plusieurs champs de recherche prometteurs et vont aider à mieux comprendre tant les causes des dysgénésies thyroïdiennes que le développement embryonnaire normal de la thyroïde chez l’homme. / Congenital hypothyroidism from thyroid dysgenesis (CHTD) is the most common congenital endocrine disorder with an incidence of 1 in 4,000 live births. CHTD includes multiple abnormalities in thyroid gland development. Among them, the most common diagnostic category is thyroid ectopy (~ 50 % of cases). CHTD is frequently associated with a severe deficiency in thyroid hormones (hypothyroidism), which can lead to severe mental retardation if left untreated. The newborn biochemical screening program insures the rapid institution of thyroid hormone replacement therapy. Even with early treatment (on average at 9 d), subtle developmental delay is still be observed in severe cases (i.e., IQ loss of 10 points). Although there have been some reports of familial occurrence (in 2% of the cases), CHTD is mainly considered as a sporadic entity. Furthermore, monozygotic (MZ) twins show a high discordance rate (92%) for thyroid dysgenesis and female predominance is observed in thyroid dysgenesis (especially thyroid ectopy), these two observations being incompatible with simple Mendelian inheritance. In addition, germline mutations in the thyroid related transcription factors NKX2.1, PAX8, FOXE1, and NKX2.5 have been identified in only 3% of sporadic cases and linkage analysis has excluded these genes in some multiplex families with CHTD. Collectively, these data point to the involvement of non-Mendelian mechanisms in the etiology of the majority of cases of thyroid dysgenesis. Among the plausible mechanisms are epigenetic modifications, somatic mutations occurring in the thyroid bud early during embryogenesis, or stochastic developmental events. Hence, we proposed a two-hit model combining germline and somatic (epi)genetic variations that can explain the lack of clear familial transmission of CTHD. In this present thesis, we assessed the role of somatic (epi)genetic variations in the pathogenesis of thyroid dysgenesis via a genome-wide as well as a candidate gene approach. Our genome wide approach revealed that ectopic thyroids show a differential gene expression compared to that of normal thyroids, with enrichment for the Wnt signalling pathway. The Wnt signalling pathway is crucial for cell migration and for the development of several endoderm-derived organs (e.g., pancreas). Moreover, a role of Wnt signalling in thyroid organogenesis was further supported by recent zebrafish studies which showed thyroid abnormalities resulting from the disruption of the Wnt pathway during different steps of organogenesis. Thus, Wnt pathway involvement in the etiology of thyroid ectopy is biologically plausible. An unexpected finding of our genome-wide gene expression analysis of ectopic thyroids was that they express calcitonin similar to normally located (orthotopic) thyroids. Such a finding, although in contradiction with our current knowledge of the embryological development of the thyroid attributes C cell origins to extrathyroidal structures (ultimobrachial bodies) upon fusion with a fully-formed, normally situated gland. Using a candidate gene approach, we were unable to demonstrate any differences in the methylation profile between ectopic and eutopic thyroids, but nevertheless we documented the presence of a differentially methylated region (DMR) between thyroids and leukocytes in the promoter of FOXE1, a gene encoding the only thyroid related transcription factor known to play a crucial role in regulating the migration of the thyroid precursors during development as shown by animal studies. We demonstrated by in vivo and in vitro studies that the methylation status of this DMR is correlated with differential expression of FOXE1 in non-tumoral tissues (thyroids and leukocytes). Knowing that DMRs are hotspots for epi(genetic) variations, its screening among CTHD patients is justifiable in our search for a molecular basis of thyroid dysgenesis, currently underway in a case-control study. The results generated during my graduate studies represent unique and novel mechanisms underlying the pathogenesis of CHTD, the etiology of which is still an enigma. They also paved the way for many future studies that will aid in better understanding both the normal and pathogenic development of the thyroid gland.