57 resultados para Educational Materials.


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Electrospraying or electrostatic atomisation is a process of liquid disruption by electrostatic forces. When liquid is brought into an electric field, charge is induced to its surface. Once the repulsive electrostatic force exceeds the liquid surface tension, the liquid disrupts into small highly charged droplets. The size of the electrosprayed droplets can range from hundreds of micrometers down to a few tens of nanometers. Electrospraying can be used not only to produce droplets, but also solid particles. The research presented in this thesis concentrates on producing drug particles by this method. In the experiments, a drug powder was dissolved in a convenient solvent and the solution was atomised. The solvent was then evaporated from the formed droplets in a drying medium and inside each droplet, a dense cluster of the dissolved drug remained. From the pharmaceutical point of view, the most important characteristics of the produced particles are size distribution, porosity, crystal form and degree of crystallinity. These properties affect the dissolution behaviour and ultimately the drug bioavailability in the body. The effects of electrostatic atomization on the aforementioned characteristics are generally not well understood. The research focused on studying these particle properties and finding possible correlations with the spraying parameters. The produced droplets were dried either under atmospheric or reduced pressure, the latter in order to improve the drying process. Special emphasis was put on implementing the spraying under reduced pressure, and the effects of the drying pressure on particle properties. Based on the results, the possibilities to enhance the dissolution of poorly soluble drugs by this method were estimated. In the course of experiments, it was also discovered that electrospraying may have a profound effect on the polymorphic form of the produced drug particles. In the light of the obtained results, it was concluded that electrospraying may offer a valuable tool to overcome some of the challenges met in modern drug development and formulation.

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Defects in semiconductor crystals and at their interfaces usually impair the properties and the performance of devices. These defects include, for example, vacancies (i.e., missing crystal atoms), interstitials (i.e., extra atoms between the host crystal sites), and impurities such as oxygen atoms. The defects can decrease (i) the rate of the radiative electron transition from the conduction band to the valence band, (ii) the amount of charge carriers, and (iii) the mobility of the electrons in the conduction band. It is a common situation that the presence of crystal defects can be readily concluded as a decrease in the luminescence intensity or in the current flow for example. However, the identification of the harmful defects is not straightforward at all because it is challenging to characterize local defects with atomic resolution and identification. Such atomic-scale knowledge is however essential to find methods for reducing the amount of defects in energy-efficient semiconductor devices. The defects formed in thin interface layers of semiconductors are particularly difficult to characterize due to their buried and amorphous structures. Characterization methods which are sensitive to defects often require well-defined samples with long range order. Photoelectron spectroscopy (PES) combined with photoluminescence (PL) or electrical measurements is a potential approach to elucidate the structure and defects of the interface. It is essential to combine the PES with complementary measurements of similar samples to relate the PES changes to changes in the interface defect density. Understanding of the nature of defects related to III-V materials is relevant to developing for example field-effect transistors which include a III-V channel, but research is still far from complete. In this thesis, PES measurements are utilized in studies of various III-V compound semiconductor materials. PES is combined with photoluminescence measurements to study the SiO2/GaAs, SiNx/GaAs and BaO/GaAs interfaces. Also the formation of novel materials InN and photoluminescent GaAs nanoparticles are studied. Finally, the formation of Ga interstitial defects in GaAsN is elucidated by combining calculational results with PES measurements.

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Forming (Arts and crafts) and children’s creative action with materials and tools are less in use in the kindergarten than before. Political focus on children’s early learning has led to shifts in kindergartens toward other specific disciplines, and requirements for individual testing also of the smallest children’s competencies within these. Kindergarten teachers, educators, researchers and participants in social debate have pointed out that there are epistemological contradictions in descriptions of kindergarten quality as well as between current kindergarten policy documents and requirements for the kindergartens’ staff. Meanwhile, the content and methods in many kindergartens are inspired by practice and philosophy in the municipal kindergartens in Reggio Emilia, Italy. Correlation between kindergartens’ formingprojects and experiences from Reggio Emilia is actualized in particular through the workshop and the studio’s role in children’s learning processes. One starting point for the thesis’ problem area is a documented need for more knowledge about kindergarten’s educational content. The overarching goal of the thesis is to develop new knowledge about how learning takes place in kindergarten through examining the field of forming in kindergartens inspired by Reggio Emilia’s atelier culture. The thesis is theoretically anchored within pragmatism, and ties kindergarten’s aesthetic operations with materials and tools to socio-cultural perspective, social constructivism and post humanistic theory. The empirical material is obtained through a qualitative study with ethnography as methodological approach. The fieldwork is conducted in kindergarten, with two leading research questions: 1) How is atelierism perceived and unfolded in Norwegian Reggio Emilia-inspired kindergartens, and 2) how is forming perceived and unfolded in Norwegian Reggio Emilia-inspired kindergartens. A comprehensive and multifaceted material is analyzed, and the results are presented in the form of three themes: The physical environment, Relations and actions in interplay, and Expression forms and forms of expression. Each of these topics are supported by examples from kindergartens’ adult voices and the constructed empirical material. Insights into how learning takes place in the kindergarten subject of forming with inspiration from the Reggio Emilia atelier culture is discussed in the tension between educational philosophy, Nordic kindergarten tradition and neoliberal trends that kindergarten teachers must adhere to. Learning potentials in children’s opportunities for action in forming in light of the atelier appears in the results of the empirical study. The educational context described is characterized by experimental and playful actions where children’s sensations, curiosity and resistance are interacting with the identity of materials and tools. The results imply aesthetic, ethical, democratic and ecological reflections, which are also valid on a practical action level. The thesis contributes to description and understanding of kindergarten’ content and young children’s learning, the importance of atelier culture as inspiration for the kindergarten, and the further development of methodology and documentation of knowledge expressions.

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The need for industries to remain competitive in the welding business, has created necessity to develop innovative processes that can exceed customer’s demand. Significant development in improving weld efficiency, during the past decades, still have their drawbacks, specifically in the weld strength properties. The recent innovative technologies have created smallest possible solid material known as nanomaterial and their introduction in welding production has improved the weld strength properties and to overcome unstable microstructures in the weld. This study utilizes a qualitative research method, to elaborate the methods of introducing nanomaterial to the weldments and the characteristic of the welds produced by different welding processes. The study mainly focuses on changes in the microstructural formation and strength properties on the welded joint and also discusses those factors influencing such improvements, due to the addition of nanomaterials. The effect of nanomaterial addition in welding process modifies the physics of joining region, thereby, resulting in significant improvement in the strength properties, with stable microstructure in the weld. The addition of nanomaterials in the welding processes are, through coating on base metal, addition in filler metal and utilizing nanostructured base metal. However, due to its insignificant size, the addition of nanomaterials directly to the weld, would poses complications. The factors having major influence on the joint integrity are dispersion of nanomaterials, characteristics of the nanomaterials, quantity of nanomaterials and selection of nanomaterials. The addition of nanomaterials does not affect the fundamental properties and characteristics of base metals and the filler metal. However, in some cases, the addition of nanomaterials lead to the deterioration of the joint properties by unstable microstructural formations. Still research are ongoing to achieve high joint integrity, in various materials through different welding processes and also on other factors that influence the joint strength.

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Fiber-reinforced composite fixed dental prostheses – Studies of the materials used as pontics University of Turku, Faculty of Medicine, Institute of Dentistry, Department of Biomaterials Science, Finnish Doctoral Program in Oral Sciences – FINDOS, Annales Universitatis Turkuensis, Turku, Finland 2015 Fiber-reinforced composites (FRC), a non-metallic biomaterial, represent a suitable alternative in prosthetic dentistry when used as a component of fixed dental prostheses (FDPs). Some drawbacks have been identified in the clinical performance of FRC restorations, such as delamination of the veneering material and fracture of the pontic. Therefore, the current series of studies were performed to investigate the possibilities of enhancing the mechanical and physical properties of FRC FDPs by improving the materials used as pontics, to then heighten their longevity. Four experiments showed the importance of the pontic design and surface treatment in the performance of FRC FDPs. In the first, the load-bearing capacities of inlay-retained FRC FDPs with pontics of various materials and thicknesses were evaluated. Three different pontic materials were assessed with different FRC framework vertical positioning. Thicker pontics showed increased load-bearing capacities, especially ceramic pontics. A second study was completed investigating the influence of the chemical conditioning of the ridge-lap surface of acrylic resin denture teeth on their bonding to a composite resin. Increased shear bond strength demonstrated the positive influence of the pretreatment of the acrylic surfaces, indicating dissolution of the denture surfaces, and suggesting potential penetration of the monomer systems into the surface of denture teeth. A third study analyzed the penetration depth of different monomer systems on the acrylic resin denture teeth surfaces. The possibility of establishing a durable bond between acrylic pontics and FRC frameworks was demonstrated by the ability of monomers to penetrate the surface of acrylic resin denture teeth, measured by a confocal scanning type microscope. A fourth study was designed to evaluate the load-bearing capacities of FRC FDPs using the findings of the previous three studies. In this case, the performance of pre-shaped acrylic resin denture teeth used as pontics with different composite resins as filling materials was evaluated. The filling material influenced the load-bearing capacities, providing more durable FRC FDPs. It can be concluded that the mechanical and physical properties of FRC FDPs can be improved as has been shown in the development of this thesis. The improvements reported then might provide long lasting prosthetic solutions of this kind, positioning them as potentially permanent rehabilitation treatments. Key words: fiber-reinforced composite, fixed dental prostheses, inlay-retained bridges, adhesion, acrylic resin denture teeth, dental material.

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The Finnish legislation requires for a safe and secure learning environment. However, the comprehensive, risk based safety and security management (SSM) and the management commitment in the implementation and development of the SSM are not mentioned in the legislation. Multiple institutions, operators and researchers have studied and developed safety and security in educational institutions over the past decade. Typically the approach has been fragmented and without bringing up the importance of the comprehensive SSM. The development needs of the safety and security operations in universities have been studied. However, in universities of applied sciences (UASs) and in elementary schools (ESs), the performance level, strengths and weaknesses of the comprehensive SSM have not been studied. The objective of this study was to develop the comprehensive, risk based SSM of educational institutions by developing the new Asteri consultative auditing process and study its effects on auditees. Furthermore, the performance level in the comprehensive SSM in UASs and ESs were studied using Asteri and the TUTOR model developed by the Keski-Uusimaa Department for Rescue Services. In addition, strengths, development needs and differences were identified. In total, 76 educational institutions were audited between the years 2011 and 2014. The study is based on logical empiricism, and an observational applied research design was used. Auditing, observation and an electronic survey were used for data collection. Statistical analysis was used to analyze the collected information. In addition, thematic analysis was used to analyze the development areas of the organizations mentioned by the respondents in the survey. As one of the main contributions, this research presents the new Asteri consultative auditing process. Organizations with low performance levels on the audited subject benefit the most from the Asteri consultative auditing process. Asteri may be usable in many different types of audits, not only in SSM audits. As a new result, this study provides new knowledge on attitudes related to auditing. According to the research findings, auditing may generate negative attitudes and the auditor should take them into account when planning and preparing for audits. Negative attitudes can be compensated by producing added value, objectivity and positivity for the audit and, thus, improve the positive effects of auditing on knowledge and skills. Moreover, as the results of this study shows, auditing safety and security issues do not increase feelings of insecurity, but rather increase feelings of safety and security when using the new Asteri consultative auditing process with the TUTOR model. The results showed that the SSM in the audited UASs was statistically significantly more advanced than that in the audited ESs. However, there is still room for improvement in the ESs and the UASs as the approach to the SSM was fragmented. It can be assumed that the majority of Finnish UASs and ESs do not likely meet the basic level of the comprehensive, risk based the SSM.

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The general aim of the thesis was to study university students’ learning from the perspective of regulation of learning and text processing. The data were collected from the two academic disciplines of medical and teacher education, which share the features of highly scheduled study, a multidisciplinary character, a complex relationship between theory and practice and a professional nature. Contemporary information society poses new challenges for learning, as it is not possible to learn all the information needed in a profession during a study programme. Therefore, it is increasingly important to learn how to think and learn independently, how to recognise gaps in and update one’s knowledge and how to deal with the huge amount of constantly changing information. In other words, it is critical to regulate one’s learning and to process text effectively. The thesis comprises five sub-studies that employed cross-sectional, longitudinal and experimental designs and multiple methods, from surveys to eye tracking. Study I examined the connections between students’ study orientations and the ways they regulate their learning. In total, 410 second-, fourth- and sixth-year medical students from two Finnish medical schools participated in the study by completing a questionnaire measuring both general study orientations and regulation strategies. The students were generally deeply oriented towards their studies. However, they regulated their studying externally. Several interesting and theoretically reasonable connections between the variables were found. For instance, self-regulation was positively correlated with deep orientation and achievement orientation and was negatively correlated with non-commitment. However, external regulation was likewise positively correlated with deep orientation and achievement orientation but also with surface orientation and systematic orientation. It is argued that external regulation might function as an effective coping strategy in the cognitively loaded medical curriculum. Study II focused on medical students’ regulation of learning and their conceptions of the learning environment in an innovative medical course where traditional lectures were combined wth problem-based learning (PBL) group work. First-year medical and dental students (N = 153) completed a questionnaire assessing their regulation strategies of learning and views about the PBL group work. The results indicated that external regulation and self-regulation of the learning content were the most typical regulation strategies among the participants. In line with previous studies, self-regulation wasconnected with study success. Strictly organised PBL sessions were not considered as useful as lectures, although the students’ views of the teacher/tutor and the group were mainly positive. Therefore, developers of teaching methods are challenged to think of new solutions that facilitate reflection of one’s learning and that improve the development of self-regulation. In Study III, a person-centred approach to studying regulation strategies was employed, in contrast to the traditional variable-centred approach used in Study I and Study II. The aim of Study III was to identify different regulation strategy profiles among medical students (N = 162) across time and to examine to what extent these profiles predict study success in preclinical studies. Four regulation strategy profiles were identified, and connections with study success were found. Students with the lowest self-regulation and with an increasing lack of regulation performed worse than the other groups. As the person-centred approach enables us to individualise students with diverse regulation patterns, it could be used in supporting student learning and in facilitating the early diagnosis of learning difficulties. In Study IV, 91 student teachers participated in a pre-test/post-test design where they answered open-ended questions about a complex science concept both before and after reading either a traditional, expository science text or a refutational text that prompted the reader to change his/her beliefs according to scientific beliefs about the phenomenon. The student teachers completed a questionnaire concerning their regulation and processing strategies. The results showed that the students’ understanding improved after text reading intervention and that refutational text promoted understanding better than the traditional text. Additionally, regulation and processing strategies were found to be connected with understanding the science phenomenon. A weak trend showed that weaker learners would benefit more from the refutational text. It seems that learners with effective learning strategies are able to pick out the relevant content regardless of the text type, whereas weaker learners might benefit from refutational parts that contrast the most typical misconceptions with scientific views. The purpose of Study V was to use eye tracking to determine how third-year medical studets (n = 39) and internal medicine residents (n = 13) read and solve patient case texts. The results revealed differences between medical students and residents in processing patient case texts; compared to the students, the residents were more accurate in their diagnoses and processed the texts significantly faster and with a lower number of fixations. Different reading patterns were also found. The observed differences between medical students and residents in processing patient case texts could be used in medical education to model expert reasoning and to teach how a good medical text should be constructed. The main findings of the thesis indicate that even among very selected student populations, such as high-achieving medical students or student teachers, there seems to be a lot of variation in regulation strategies of learning and text processing. As these learning strategies are related to successful studying, students enter educational programmes with rather different chances of managing and achieving success. Further, the ways of engaging in learning seldom centre on a single strategy or approach; rather, students seem to combine several strategies to a certain degree. Sometimes, it can be a matter of perspective of which way of learning can be considered best; therefore, the reality of studying in higher education is often more complicated than the simplistic view of self-regulation as a good quality and external regulation as a harmful quality. The beginning of university studies may be stressful for many, as the gap between high school and university studies is huge and those strategies that were adequate during high school might not work as well in higher education. Therefore, it is important to map students’ learning strategies and to encourage them to engage in using high-quality learning strategies from the beginning. Instead of separate courses on learning skills, the integration of these skills into course contents should be considered. Furthermore, learning complex scientific phenomena could be facilitated by paying attention to high-quality learning materials and texts and other support from the learning environment also in the university. Eye tracking seems to have great potential in evaluating performance and growing diagnostic expertise in text processing, although more research using texts as stimulus is needed. Both medical and teacher education programmes and the professions themselves are challenging in terms of their multidisciplinary nature and increasing amounts of information and therefore require good lifelong learning skills during the study period and later in work life.

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For the past decades, educational large-scale reforms have been elaborated and implemented in many countries and often resulted in partial or complete failure. These results brought researchers to study policy processes in order to address this particular challenge. Studies on implementation processes brought to light an existing causal relationship between the implementation process and the effectiveness of a reform. This study aims to describe the implementation process of educational change in Finland, who produced efficient educational reforms over the last 50 years. The case study used for the purpose of this study is the national reform of undivided basic education (yhtenäinen peruskoulu) implemented in the end of the 1990s. Therefore, this research aims to describe how the Finnish undivided basic education reform was implemented. This research was carried out using a pluralist and structuralist approach of policy process and was analyzed according to the hybrid model of implementation process. The data were collected using a triangulation of methods, i.e. documentary research, interviews and questionnaires. The data were qualitative and were analyzed using content analysis methods. This study concludes that the undivided basic education reform was applied in a very decentralized manner, which is a reflection of the decentralized system present in Finland. Central authorities provided a clear vision of the purpose of the reform, but did not control the implementation process. They rather provided extensive support in the form of transmission of information and development of collaborative networks. Local authorities had complete autonomy in terms of decision-making and implementation process. Discussions, debates and decisions regarding implementation processes took place at the local level and included the participation of all actors present on the field. Implementation methods differ from a region to another, with is the consequence of the variation of the level of commitment of local actors but also the diversity of local realities. The reform was implemented according to existing structures and values, which means that it was in cohesion with the context in which it was implemented. These results cannot be generalized to all implementation processes of educational change in Finland but give a great insight of what could be the model used in Finland. Future studies could intent to confirm the model described here by studying other reforms that took place in Finland.

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The topic of this dissertation is the didactic exhibition in the Arts and Crafts subject. Exhibiting student work and art and form culture is part of a long professional tradition in the field. Yet, exhibition as form and as a way of learning are inadequately explored and debated. The didactic problem area of the thesis, where studies of formative practices are central, place it within the research field of Educational Slojd. The didactic standpoint and main theoretical perspective relate the project to the Arts didactics research field at the University College of Bergen where the aim is to develop an alternative didactics thinking for the arts; a rhetoric arts didactics. Didactic focus is shifted from the relationship between teacher – pupil – teaching materials, to studies of how knowledge is formulated in specific practices. The thesis has a premise that every exhibition has its own rhetoric and that didactics is inscribed in this rhetoric in the broadest and cultural sense. Through impulses from classical rhetoric and recent text theory, the thesis challenges the Arts and Crafts’s own idiom, its theoretical foundation and didactic grasp such as shown in the discourse established by the discipline and its specific exhibitive practices, as well as studying the relationship between verbal language and the discipline’s own register. The overall objective is to develop knowledge about exhibition rhetoric and its potential as a knowledge and learning arena in this field, and thereby contribute to developing a rhetoric didactics for the Arts and Crafts subject. This raises questions such as: How is an exhibition considered to be used and understood in the subject’s didactics texts and texts about didactics? How do different exhibition spaces inscribe conditions for exhibition work? How can a rhetoric perspective of didactics make aspects of an exhibition’s form register visible and contribute to knowledge of the creative processes in an exhibition? How do some selected exhibitions inscribe creativity and learning? What can a rhetoric perspective bring to the Arts and Crafts? A rhetoric didactics perspective includes knowledge of the tradition. A historical-ideological overview traces how exhibition, of both pupil/student work and of art and form culture, are used and considered as used in the discipline over time. This part can be read separately, but in this thesis, is primarily conceived as a backdrop for the development of the dissertation’s main rhetoric perspective. The empirical data are collected from my teacher training institution and consist of specific exhibition spaces and practices, of which my own production of two exhibitions can link the research to artistic development work. A rhetoric didactics is concrete, specific and contextual. The rhetoric readings are descriptive and show how culture and nature, temporality, materiality and technology are inscribed in the exhibition’s form. Didactic reflection develops from, and close to, the rhetoric readings of the exhibition’s form and content to finally arrive at a rhetorical concept for creativity and learning.

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For the past decades, educational large-scale reforms have been elaborated and implemented in many countries and often resulted in partial or complete failure. These results brought researchers to study policy processes in order to address this particular challenge. Studies on implementation processes brought to light an existing causal relationship between the implementation process and the effectiveness of a reform. This study aims to describe the implementation process of educational change in Finland, who produced efficient educational reforms over the last 50 years. The case study used for the purpose of this study is the national reform of undivided basic education (yhtenäinen peruskoulu) implemented in the end of the 1990s. Therefore, this research aims to describe how the Finnish undivided basic education reform was implemented. This research was carried out using a pluralist and structuralist approach of policy process and was analyzed according to the hybrid model of implementation process. The data were collected using a triangulation of methods, i.e. documentary research, interviews and questionnaires. The data were qualitative and were analyzed using content analysis methods. This study concludes that the undivided basic education reform was applied in a very decentralized manner, which is a reflection of the decentralized system present in Finland. Central authorities provided a clear vision of the purpose of the reform, but did not control the implementation process. They rather provided extensive support in the form of transmission of information and development of collaborative networks. Local authorities had complete autonomy in terms of decision-making and implementation process. Discussions, debates and decisions regarding implementation processes took place at the local level and included the participation of all actors present on the field. Implementation methods differ from a region to another, with is the consequence of the variation of the level of commitment of local actors but also the diversity of local realities. The reform was implemented according to existing structures and values, which means that it was in cohesion with the context in which it was implemented. These results cannot be generalized to all implementation processes of educational change in Finland but give a great insight of what could be the model used in Finland. Future studies could intent to confirm the model described here by studying other reforms that took place in Finland.

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Teema: Yliopistohistoria.