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L'émail dentaire est la couche de tissu externe calcifié recouvrant la couronne de la dent; c’est la structure la plus minéralisée du corps humain. L'émail est synthétisé par l’améloblaste au cours du développement de la dent, mais cette population cellulaire dégénère et régresse totalement lorsque la dent devient fonctionnelle. L'émail mature est donc complètement dépourvu de cellules et de contenu protéique. L’amélogénine, la principale protéine de l’émail a la capacité de s’assembler en structures très organisées de type nanochaînes qui vont guider et réguler les cristaux d’hydroxyapatite de l’émail en formation. Le Leucine Rich Amelogenin Peptide (LRAP) est un produit de l'épissage alternatif du gène de l'amélogénine ; c’est un peptide court (56kDa), composée des séquences actives et N- et C-terminales de la protéine d’amélogénine complète. Dans ce travail, nous avons cherché à comprendre le rôle de LRAP dans l’amélogenèse. Nous avons montré 1) que LRAP présentait les mêmes propriétés d’auto-assemblage que la forme complète d’amélogénine et ses produits de clivage ; 2) que LRAP possédait les même propriétés de régulation des phosphates de calcium que la protéine complète ; et 3) que la conformation de la forme phosphorylée de LRAP était modifiée par une augmentation de la concentration de calcium dans le milieu environnant contrairement à la forme déphosphorylée de LRAP. Dans un second temps, nous avons étudié les propriétés de signalisation du peptide et confirmé nos résultats de minéralisation sur des modèles de culture de cellules de type améloblastique LS8 et ALC in vitro et sur un modèle de culture de germe de première molaire de souris ex vivo. Nous avons montré que la présence des deux formes de LRAP, active la cinétique de différenciation des cellules LS8 et ALC in vitro et favorise la formation de cristaux d’HAP organisés et allongés. Dans les germes en culture, la présence de LRAP(+P) dans un milieu minéralisant permet une augmentation de la densité et du volume de minéral formé alors que dans un milieu standard, il favorise la différenciation des germes. LRAP(-P) entraine en revanche, la synthèse par les améloblastes sécréteurs de longs et fins cristaux d’HAP bien organisés. Ce travail pourrait ouvrir de nouvelles stratégies de régénération des tissus de l'émail afin de traiter des altérations de la couche d'émail résultant de lésions carieuses à l’aide du LRAP(-P) ou de troubles génétiques comme l’amélogenèse imparfaite en utilisant plutôt le LRAP(+P). / Tooth enamel is the outer calcified layer covering the crown of the tooth; it is the most mineralized tissue of the human body. Enamel is synthesized by ameloblast during tooth development, but this cell population degenerates and regresses when the tooth becomes fully functional. The mature enamel is completely devoid of cells and protein content. The amelogenin, the main protein of the enamel has the ability to assemble into highly organized nanochains, which will guide and regulate the deposition of hydroxyapatite crystals during enamel formation. The Leucine Rich Amelogenin Peptide (LRAP) is a product of alternative splicing of the amelogenin gene; it is a short peptide (56kDa), composed of the active N- and C-terminal sequences of the complete amelogenin protein. The aim of this work is to understand is to understand the role of LRAP in enamel formation. We have shown 1) that LRAP presents the same self-assembling properties as the full-length form of amelogenin and its cleavage products; 2) that LRAP exhibits the same calcium phosphate regulating properties as the full-length protein; and 3) that the conformation of the phosphorylated form of LRAP was modified by increasing concentration of calcium in the surrounding medium unlike the dephosphorylated form of LRAP. In the second part of this work, we have studied the peptide signaling properties and confirmed our mineralization results on ameloblast lineage cell culture models (LS8 and ALC) in vitro and on mice first molar germ culture model ex vivo. We have shown that the presence of both forms of LRAP activate the kinetic of differentiation of LS8 and ALC cells in vitro, and results in the formation of organized elongated HAP crystals. In the germ culture experiments, addition of LRAP(+P) in a mineralizing medium induces an increase in the density and volume of the mineral formed whereas in the standard medium, it promotes differentiation of the germs. LRAP(-P) leads to the synthesis by secretory ameloblasts of well organized long and fine HAP crystals. This work may lead the way toward new strategies for enamel tissue regeneration in order to treat alterations in the enamel layer resulting from carious lesions with the LRAP(-P) or genetic disorders such as amelogenesis imperfecta using LRAP(+P).

Effective management of knowledge assets is key to surviving in today's competitive business environment. This is particularly true for large organisations, where employees have difficulties identifying where or with whom the knowledge lies. Expertise is one of the most important knowledge assets and largely resides in the heads of employees. Many attempts have been made to help locate employees with the right expertise; however, the existing systems (often referred to as expertise finding systems) carry several flaws. In organisations, there are several potential sources where expertise evidence might be found. These sources have been used by the existing approaches to profile employees' expertise. Unfortunately, there has been limited research showing whether these sources contain useful evidence of expertise. Moreover, the majority of existing approaches have not been designed to integrate with the organisations' work practices; nor have they investigated the socio-ethical challenges associated with the adoption of such systems. Therefore, there is a need for expert finding systems that utilise useful sources of expertise and integrate into existing work practices. Through industry involvement, this research has explored and validated email content as a source for expertise profiling. This thesis provides an overview of the traditional and current approaches to expertise finding. The development and implementation of the EKE (Email Knowledge Extraction) system which tries to overcome the aforementioned challenges is presented. EKE has been evaluated by end-users from both industry and academia. The evaluation results suggest that EKE is a useful system that encourages participation, and that in many cases may assist in the management of knowledge within organisations.

The use of email as a communication and information sharing medium in large, complex, globally distributed engineering projects is widespread; yet there exists little understanding of the content of the emails exchanged and the implications of this content on the design project, design records and contracts. The importance of these issues is underlined by the fact that email records can now be required as evidence in legal disputes. It follows that the overall aim of this research is to assess the role and use of email in engineering design projects. A state-of-the-art review of literature pertaining to email is reported, along with a review of information and communication processes in engineering design projects. The primary contribution of this thesis is the creation of a content based approach for analysing the role and use of email in engineering design projects. This centres on the development and application of a coding scheme to email text, identifying what subject matter an email relates to, why it was sent, and how its content is expressed. Results are then analysed with respect to the frequencies of each code and other variables, including how coding varies between different senders and throughout the project duration. The second key contribution of this thesis is the analysis of emails and content in an engineering setting by applying the aforementioned approach to two case studies. The major case study concerned a large, complex, globally distributed, multimillion pound systems engineering project, from which 16 000 emails were obtained. It was found that emails are mainly used to transfer information but also to support management functions. Emails facilitate design work but little of this takes place explicitly in the email content. Characteristics of a project affect the subject matter or emails but have little effect on why they are sent. User roles and personal preferences also influence email use. If was found that the purposes for sending emails varied over the duration of a project; it was further determined that these changes could be used to identify project progress and design activity. Implications of the findings are identified in relation to: information management, knowledge management, project management, collaboration and email practice. Significantly, emails do contain potentially important design information and because these often support decisions made elsewhere, emails should be integrated with wider records. More consideration and training should be given to the use of project standards for email use and guidelines for composition. Changes in email use over the project duration could be a potential tool for project managers to identify design progress and possible issues in a project.

Email provides the average person with the ability to instantaneously communicate with people across the planet. However, the ease of this communication not only allows people to exchange information, but can also generate a large volume of messages. The methods of interacting with this repository currently in use are far from adequate. This thesis focuses on the development of a new interface for managing one's inbox and mail folders. The approach provides the user with a data visualization of an overview of the entire mailbox, or a chosen subset, at once. The tool includes interactions that allow a user to focus his or her attention on specific email and delve deeper into it in a simple intuitive fashion. A user study confirmed the usefulness of the resulting system.

The purposes of this study were to determine the factors that influence the use of e-mail by principals, the purposes for which e-mail messages were sent and received, and the impact of experience and training in the areas of computers and e-mail. A survey was sent to a stratified random sample of 620 elementary, middle/junior high, and high school principals of the Central Appalachian Region. Respondents were asked to provide data regarding demographics, accessibility to hardware and software, computer and e-mail experience and training, uses of e-mail, and items that influence e-mail use. Eleven research questions and 10 hypotheses were addressed. Data analysis included descriptive statistics, chi-square, ANOVA, multiple regression, and factor analysis. At the.05 level of significance eight null hypotheses were retained and two rejected. Factor analysis identified four factors for e-mail users and five factors for non-users. E-mail was used by 59.7% of respondents. There was no relationship between level of use and gender, age, highest degree earned, or total years of educational experience. The predictors of e-mail use were computer experience, accessibility to resources, and training. Keyboarding skills and use of e-mail by superiors, fellow principals, and teachers were not indicators of e-mail use. Principals primarily use e-mail for administrative tasks and secondarily for accessing and retrieving information. Training is essential to the effective implementation and use of e-mail. There were six primary training methods for computers and e-mail. Factor analysis revealed that e-mail users have hardware and software resources, training, support, and encouragement to use e-mail to obtain educationally beneficial and appropriate information. Non-users were not comfortable with the technology. Principals must be cognizant of e-mail's capabilities and potential ramifications upon the educational community and provide the role model for the use of technology. E-mail has the potential to break down barriers of geographical isolation and instill a sense of community. If future educational leaders are to be prepared to meet the challenges of an information age, colleges of education need to provide instruction in the use of computers and e-mail.

This study explores the most current theories surrounding organization-public relationship measurement, which is one approach used to verify the effectiveness of public relations programs. The study attempted to define and test two new factors that may affect organization-public relationships, which are identified as public image and public trust. Existing factors used to test such relationships, such as trust, satisfaction, commitment, and control mutuality, focus on testing the perceptions stakeholders have about an organization based upon their interpersonal relationship with that organization. However, in organizations where the dominant coalition still does not view public relations as a management function, use of the existing scales to measure the long-term effectiveness of public relations programs can be dangerous and inaccurate, especially when public relations practitioners are not responsible for creating, maintaining, or managing those organization-public relationships. A 65-item questionnaire was administered via email to a convenience sample of 5,799 stakeholders. A total of 1,193 completed questionnaires were received; however, a response rate could not be reported because the questionnaire was posted to a popular Internet site. The survey instrument tested new items for public image and public trust, as well as the existing relationship items of trust, satisfaction, commitment, and control mutuality defined by Hon and J. E. Grunig (1999). Factor analysis defined two new indices for public image and public trust and Cronbach's alpha further supported the reliability of these measures. Also, Cronbach's alphas tested reliable for trust, satisfaction, commitment, and control mutuality. However, when all items for public image, public trust, trust, satisfaction, commitment, and control mutuality were subject to factor analysis, all but four items weighted into one factor. This suggests the need to further explore new measurement tools for assessing the long-term effectiveness of public relations programs beyond the organization-public relationship.

This thesis is concerned with explicating the role of language in mobilising action through management emails. Situated within the context of organisational change in a globalised manufacturing business, the project is framed by behavioural observations from management scholars Palmer and Hardy (2000) of mobilisation strategies that utilise linguistic resources since they: (a) involve a sense of obligation or inclination in directives; (b) show how co-operation will produce mutual benefits; (c) construct desired actions as legitimate, beneficial or inevitable; and (d) use past or anticipated meanings, for or against certain actions. Systemic Functional Linguistics is the underlying framework employed to provide a theoretically principled account of the intuitively derived observations from Palmer and Hardy (2000) which are applied to a sample of twenty-seven email texts, through corpus- and text-based analysis. A major finding is that the representation of action is enacted interpersonally through the verbal group. This view complements experientially dominated accounts of the verbal group which focus on the tense system. Further, action is found to be motivated through the negotiation of evaluative stance. By relating the grammar of the verbal group as well as other resources to the discourse semantics of Appraisal, modulation (of obligation or inclination) is found to be enabled by both negative as well as positive judgements of capacity. Specifically, judgements of capacity are re-interpreted as invocations of high obligation as managers seek to mobilise (further) positive performance. The analysis demonstrates that elements in the verbal group (complex) and Appraisal co-opt action through enabling positioning of the writer, in terms of assessing and grading categorical meanings, manipulating interpersonal time, or foregrounding solidarity. A significant contribution to the thesis is an extension of the system of GRADUATION: FOCUS (Hood, 2004a) through the demonstration of how resources of the verbal group negotiate expectations of appearances and achievements. This study has also extended the resources of GRADUATION: FORCE by applying it to the management context. The practical contribution of the study is that these insights may more explicitly inform management training and enable managers to participate more effectively within their community of practice.

The documentation of complete and timely as-built information related to construction projects is essential for tracking progress, planning corrective action, and analyzing the schedule. The collection of site information, however, is currently a challenging, time-consuming, and error-prone manual process. To improve the tracking of as-built information, this research focused on the development of a low-cost voice-visual framework that utilizes commonly available communication tools such as email and interactive voice response (IVR). The goal of this research was to create project-wide bidirectional communication between site personnel and head office to automate the tracking of daily site information. The research involved an in-depth analysis of the possible site events and progress-tracking needs related to construction activities. Accordingly, activity-specific email forms and logical-flow diagrams were developed as a means of facilitating site data collection. A framework was then developed that integrates several components: the developed tracking forms; a cloud-based IVR service; a customized scheduling application; and an email application. During construction, the automated system identifies eligible activities to be tracked; collects as-built details from the relevant supervisors; and uses the daily time segments of the schedule as an integrated depository for all as-built details, including progress information, events by all parties, and requests for information (RFIs), quality/safety issues, and other video/audio/drawing-markup notes. The developed system generates detailed as-built schedule that clearly show the evolution of all as-built events and their accurate timing on the daily segments for each activity. The project schedule is thus converted from a static report into information-rich, visualization media, and decision-support tool that provides decision makers with timely progress details so that they can easily follow the project progress , facilitates schedule updates, facilitates accurate schedule forensics, delay analysis, , and the planning of appropriate corrective action. The developed framework was validated though a number of case studies that demonstrated its usefulness and practicality. This research contributes to construction efficiency through the facilitation of bidirectional communication between site personnel and head office and the provision of timely and legible as-built data for decision-making. Ultimately, the research will assist construction firms to have better control over construction projects and more effective decisions during construction through improved communication.

Enterprises spread messages usingcomputer networks has become a trend due to popularity of the Internet. It is important for enterprises to select appropriate network media to achieve high effectiveness. It¡¦s even more important for Internet marketing companies to deploy marketing strategies given all possible media selections. The network media is progressing with new technical applications, such as email, blog, micro-blog and social network, etc. Each has its own development background and can achieve different effectiveness. The study of this thesis is to explore the differences of spread rates, diffusion time distribution etc. by spreading the same network messages with different network media (such as Email, social network, Facebook etc.). It will help enterprises to understandthe characteristics and effectiveness of each network medium. As a result, enterprisescan learn how to choose the right media to get the best message diffusion result. The study shows that various message carriers willexhibit different effectivenessdue to the nature of message contents. For example, commercial messages can be best delivered with Facebook while messages of special interests can be effectively delivered by email. Regardless what medium is chosen, two common phenomena can be observed: high click rate within the first 24 hours, and the low click rate in midnight.Enterprises will do a good spread messages plan using computer networks in known the two common phenomena.