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Traumatic brain injury (TBI) is a relatively unknown disease considering the tens of millions of people affected around the world each year. Many TBI patients die from their injuries and survivors often suffer from life-long disabilities. The primary injury initiates a variety of cellular and molecular processes that are both beneficial and detrimental for the brain, but that are not fully understood. The focus of this thesis has been to study the role of astrocytes in clearance of dead cells after TBI and to identify injury specific proteins that may function as biomarkers, by using cell cultures, animal models and in cerebrospinal fluid (CSF) from TBI patients. The result demonstrates a new function in that astrocytes, the most numerous cell type in the brain, engulf dead cells after injury both in cell cultures and in adult mice and thereby save neurons from contact-induced apoptosis. Astrocytes are effective phagocytes, but degrade the ingested dead cells very slowly. Moreover, astrocytes express the lysosome-alkalizing proteins Rab27a and Nox2 as well as major histocompatibility complex class II, the receptors on which antigens are being presented. By lowering the pH of the lysosomes with acidic nanoparticles, the degradation increases, but the astrocytes still remained less effective than macrophages. Taken together, the data indicates that the low acidification in astrocytes can preserve antigens and that astrocytes may be able to activate T cells. The expression and secretion of injury-specific proteins was studied in a cell culture model of TBI by separate mass spectrometry analysis of cells and medium. Interestingly, close to 30 % of the injury-specific proteins in medium are linked to actin, for example ezrin of the ezrin/radixin/moesin (ERM) protein family. Ezrin, but none of the other ERM proteins or actin, is actively secreted after injury. Extracellular ezrin also increases in CSF in response to experimental TBI in rats and is present in CSF from TBI patients, indicating that ezrin is a potential biomarker for TBI.

På sociala nätverkssidor tillåts användarna att presentera sig själva. Sociala medier ger användarna möjlighet att styra och kontrollera sin presentation på ett annat vis än hur presentationen kan styras i ansikte-mot-ansikte situationer. De sociala medierna tenderar dock att rikta sig till en bredare publik i jämförelse med den interpersonella situationen. Således måste användarna på de sociala medierna ge en konsekvent bild av sig själva för att inte ge en annorlunda självpresentation än den som har givits offline. Hur presentationer online skiljer sig från varandra har nyligen börjat studeras. Exempelvis finner vi en kartläggning om hur Facebook skiljer sig från LinkedIn i användarnas sätt att presentera sig. Fältet efterfrågar dock mer forskning som undersöker enskilda medier för att se om man i det valda mediet har mindre eller större tendenser till att skilja mellan presentationen online respektive offline. Utefter detta har vi identifierat studiens forskningslucka då vi konstaterat att det saknas forskning om hur vi presenterar oss på Instagram. Studiens syfte är att undersöka sociala mediers betydelse för människors självpresentation. Vi valde att tillämpa en kvalitativ metod. Vi genomförde semistrukturerade samtalsintervjuer med sex deltagare. Samtalsintervjun utgjorde den interpersonella offlinepresentationen som därefter jämfördes med onlinepresentationen, vilket utgjordes av deltagarnas instagraminnehåll. Studiens teoretiska ramverk behandlar publikanpassning och tre olika former av missrepresentation: idealisering, uteslutande av demografiska aspekter samt ett ogiltigt självkoncept. Vi har via innehållsanalyser letat efter just dessa fenomen. Studiens resultat visar att självpresentationen på Instagram är ytterst begränsad och dessutom uteslutande av fullständiga kontexter. Vi finner ingen påtaglig publikanpassning utan finner snarare att användarna utgår ifrån att deras följare, publik, är väl insatta i deras liv och därmed förstår den fullständiga kontexten som är utesluten i en uppladdad bild. Resultatet visar också att de tre formerna av missrepresentation inte går att tillämpa på Instagram som socialt medium trots att vi finner små tendenser av idealiserande. Idealiserandet beror antagligen främst på Instagrams tekniska utformning. / At social networking sites, the users are allowed to present themselves. Social media are providing the users with opportunity to control their presentations in a way that is not possible in face-to-face communication. The difference, when it comes to audience, is that the social media sites are tending to speak to a much wider audience than interpersonal situations. This leads to that the users have to communicate a consistent self presentation so that the online presentation will match the presentation given in offline situations. How online and offline presentations differs from each other is a relatively new subject. New studies show how Facebook’s and LinkedIn’s users are presenting themselves differently in these different kinds of mediums. Still, the field of communication and social media are requesting more research on how single mediums tend to differ in the presentation in contrast to the presentation which takes place in real life. Through this, and the fact that Instagram is an unexplored medium, were we able to identify this studies purpose, which is to investigate and create an understanding of the significance that social media has on self presentation. We used a qualitative approach in this study. We executed semi-structured interviews with six participants, which came to be treated as offline presentations of the participants lives. This presentation where later compared with content analysis to the participants Instagram profile. The theoretical framework of this study discusses audience accommodations and three different forms of misrepresentation online: idealizing, exclusion of demographic aspects and an invalid concept of the self. The result of the study shows that the self presentation on Instagram is highly limited and excluding of surrounding contexts. We do not find any substantial audience adjustment but instead that Instagram users tend to presuppose that their audience are well aware of their life and therefor are aware of the full context. The result also shows that the three forms of misrepresentation online cannot be applied on Instagram even if we see some tendency of idealizing.

In recent years, the internet has exploded of images. Not at least in the popular photo-sharing network Instagram as one of the fastest growing social network for the moment. Millions of people around the world share pictures and expose themself for friends and family. We were therefore interested in which experiences and attitudes users have towards their identities in relation to their self-image and self-presentation on Instagram. Furthermore, whether they in general have a primary interest in using Instagram as a tool to experiment with images to present their identity on Instagram, in which way they approach their Instagram follower’s expectations on how they present themselves on Instagram and if they are aware of any strategies in their self-presentation on Instagram. The result of this study is the fact that our respondents thinks that they do not intend to have a primary interest in experimenting with images on Instagram to present their identitiy, it is rather something that comes naturally in how they present themselves on Instagram. The primarily purpose of using Instagram do not appear to be for satisfying an experimental need in self-presentation on Instagram. It is rather to satisfy a social need. Following, it has emerged that they seems to have a varied self-awareness in terms of strategies and reasons for self-presentation and that they are significantly influenced by their followers expectations on their identity presentation.

The Internet has potential to deliver information to Web users that have no other way of getting to those resources. However, information on the Web is scattered without any proper semantics for classifying them and thus this makes information discovery difficult. Thus, to ease the querying of this huge bin of information, developers have built tools amongst which are the search engines and Web directories. However, for these tools to give optimal results, two factors need to be given due importance: the users’ ability to use these tools and the bandwidth that is present in these environments. Unfortunately, after an initial study, none of these two factors were present in Mauritius where low bandwidth prevails. Hence, this study helps us get a better idea of how users use the search tools. To achieve this, we designed a survey where Web users were asked about their skills in using search tools. Then, a jump page using the search boxes of different search engines was developed to provide directed guidance for effective searching in low bandwidth environments. We then conducted a further evaluation, using a sample of users to see if there were any changes in the way users access the search tools. The results from this study were then examined. We noticed that the users were initially unaware about the specificities of the different search tools thus preventing efficient use. However, during the survey, they were educated on how to use those tools and this was fruitful when a further evaluation was performed. Hence the efficient use of the search tools helped in reducing the traffic flow in low bandwidth environments.

Many universities, libraries, government organisations and companies are implementing digital repositories to collect, preserve, administer and distribute their collections via the World Wide Web. In the process of building these digital archives and collections, images such as maps are often are captured in an uncompressed, high-resolution format to preserve as much detail as possible. This process, of high-resolution archiving gives rise to the problem of providing the end-user with access to these large (high-resolution) images, such as maps. This dissertation investigates methods of storing and delivering large images over the Internet while limiting the amount of data being transferred; and also documents efforts to incorporate large image support within the DSpace platform. An end-user usability study of various large image support solutions was conducted to establish how current digital repository large image solutions compared to commercial large image solutions. The study showed that the commercial large image solutions were superior to current digital repository solutions. A prototype large image solution was developed with a specific aim to provide DSpace with mechanisms to import and deliver large images in a bandwidth-conscious manner. It was found that by implementing and extending currently available open source large image processing software, large image support could be provided to the DSpace platform with minimal or no modification to the DSpace source code. An end user evaluation study was conducted to establish the usability and effectiveness of the prototype large image support solution. It was found that the prototype system provided an easy to use solution that provides DSpace with an effective large image archiving and delivery mechanism.

Open access and open resources have gained much attention from the world in the last few years. The interest in sharing information freely by the use of the World Wide Web has grown rapidly in many different fields. Now, information is available in many different data forms because of the continuous evolution in technology. The main objective of this thesis is to provide content creators and educators with a solution that simplifies the process of depositing into digital repositories. We created a desktop tool named ORchiD, Open educational Resources Depositor, to achieve this goal. The tool encompasses educational metadata and content packaging standards to create packages while conforming to a deposit protocol to ingest resources to repositories. A test repository was installed and adapted to handle Open Educational Resources. The solution proposed is centered on the front-end application which handles the complex objects on the user desktop. The desktop application allows the user to select and describe his/her resource(s) then creates the package and forwards it to the specified repository using the deposit protocol. The solution is proved to be simple for users but also in need of further improvements specifically in association to the metadata standard presented to user.

Information and Communication Technologies (ICTs) in general, and mobile phones in particular, have demonstrated positive outcomes in the various social transformation and human development dimensions. As a result, many researchers have focused on ICTs innovations targeting the poor. Among the poor are the low-skilled day-labourers who belong to the Day-labour Market (DLM), which is also made up of employers, job-brokers and intermediary organisations. The DLMs’ main activities involve a great deal of travelling in search of jobs by workers and a search for workers by employers. These travels place heavy economic pressure on the day-labourers, hence reducing their net earnings while they struggle with extreme poverty. The first objective of our study was to find out how and which ICT interventions can be used to alleviate the challenges faced by the DLM stakeholders. The nature of our problem resembled studies that use ICTs to reduce travel distance. Such studies fall under subjects such as teleactivities and teleworking/telecommuting, and advocate for prospects of working anywhere anytime. These studies have not received much research attention in the developing world. They have mainly been done in the developed world, and mostly on white-collar workers and organisations. This brought about our second objective: to find out whether the ICT interventions for the DLM could be studied under teleworking/telecommuting and whether the telecommuting benefits can be realised for the blue-collar workers. Our research methodology was Action Research applying three case studies. We used participant observation and both structured and unstructured interviews for qualitative data collection and questionnaires to collect quantitative data. Contextual inquiry, prototyping and technology probe was applied as our design technique. The prototypes were evaluated in-situ to assess usability and uncover user experience. We mainly employed qualitative data analysis, but where appropriate, triangulated with quantitative data analysis. The research outcomes were divided into three categories: (1) the knowledge on the DLM characteristics which depicted different forms of the DLM and shaped our design process, (2) the DLM software designs tested as prototype applications and software artefacts deployed for use by the DLM and (3) the meaning and the state of telecommuting/teleworking before and after our experiments in the DLM. In the first category, appreciating the challenges faced by our primary target users, the day-labourers, helped shape our designs and our inquiry to include intermediation. With regard to the prototype applications, they included the remote mobile applications and the web-based server side software systems. Although most of these applications where meant for proof of concept, some of them ended up being implemented as fully functional systems. Finally, in the third finding, travel reduction using ICTs (mainly the mobile phones) had been practised by some of the DLM stakeholders even before the commencement of our study. After our intervention, we discovered that implementing telecommuting/teleworking within the DLM may be possible, but with a raft of redefinitions and changes in technology innovations. We therefore identified factors to consider when thinking of implementing telecommuting among blue-collar employees, organisations and employers.

The present study investigates the verbal strategies of self-presentation that humanist scholars employed in contests of honor during the early fifteenth century. The focus of this study is George of Trebizond (1395-1472/3), a Cretan scholar who emigrated to Italy in 1416, taught in Venice, Vicenza, and elsewhere, served as an apostolic secretary in Rome, and composed the first major humanist treatise on rhetoric, his Rhetoricorum libri quinque, in 1433/34. Trebizond feuded with many prominent humanists during his career, including Guarino of Verona (1374-1460) and Poggio Bracciolini (1380-1459). His quarrels with both men illustrate how humanist conflicts were the sites upon which Quattrocento scholars won or lost honor via literary activities designed to appeal to a public audience of peers and patrons. Humanists wrote to denigrate publicly their competitors, casting them as ignorant and morally corrupt, and to praise themselves as eloquent and virtuous. Although Renaissance scholarship has long acknowledged the humanist pursuit of glory, the linguistic means by which humanists contested honor remains understudied. The present study contends that Quattrocento contests of honor were conducted using standard sets of oppositional categories, themes, and literary models. Additionally, I argue that an analysis of the linguistic strategies of self-presentation provides a more complex and complete picture of Quattrocento humanism and of individual humanists as historical figures. Following an introductory discussion of George of Trebizond and Quattrocento humanism in Chapter One, the next three chapters of this dissertation address individual themes evident in Trebizond’s correspondence. Chapter Two examines the anti-Greek language that dominated Trebizond’s dispute with Guarino in 1437. Chapter Three explores the language of restraint and rational self-control in Trebizond’s feud with Poggio between 1452 and 1453. Chapter Four evaluates humanist concepts of masculinity in Trebizond’s feuds with both men. Chapter Five steps back from a deep thematic reading of Trebizond’s correspondence to consider invective as a literary genre that was a preferred vehicle for humanist self-presentation. This final chapter studies two additional feuds, between Guarino and Niccolò Niccoli, and Poggio and Lorenzo Valla, to understand better Trebizond’s experiences as a reflection of the broader culture of which he was a part.

The general purpose this study has been to determine the perception of MBA students on quality lecturing. Business schools are concerned about how learners evaluate the lecturing experiences in order to monitor the quality of the lecturing. Student evaluations are assumed to mirror relative stable views which hold implications for how tertiary institutions act upon and reward the educational practices of lecturers. It is evident from prior research that broad reaching claims concerning student satisfaction cover large alternatives in terms of a construct being evaluated. Links between what is measured, and how this information should be utilised, are not always well-defined. Previous studies suggest that student satisfaction and perception is a multifaceted concept consisting of several complex dimensions. The true muscle of lecturing is crucial leadership ability. It is not just a lecture or a presentation. Lecturing is a set of skills. It is not just about a gift. It is a set of practices that should be rehearsed, mastered and delivered. A lecturer will certainly not deliver a faultless lecture, but might bring an influential and current lecture. The skill set of lecturing is both a skill and a discipline. A lecturer should learn and practices the discipline; then the skill will be conquered. Everyone can be a powerful and skillful presenter, but it will take time, rehearsal and vigor to overcome mediocrity. The management of business schools should comprehend the importance of quality lecturing. Without emphasis on lecturing, the perceived quality of a business school could be misconceived by students. Quality lecturing should always be a focus point and the emphasis on improved effectiveness by management. / MBA, North-West University, Potchefstroom Campus, 2014