Developing casual conversation skills of pre-school children learning English as a foreign language in the home context

University of Technology, Sydney. Faculty of Education.The broad aim of this thesis is to investigate the development of the English conversation of two, pre-school children, who are learning English as a foreign language in the home context, by focusing on their language skills and their learning processes. In order to do this, there are two major aims: first, to describe the development of the children's English conversational language skills over a four year period, by focusing on their construction of five genres of casual conversation. And second, to describe the key learning processes involved in the development of the children's English conversational skills, in particular focusing on the role of the scaffolding process. The procedure involves the analysis of spoken data collected from the two children. The data is arranged according to genre. Data from the modeling and joint negotiation stages of the pedagogical cycle focuses on the role of the scaffolding process in the children's learning. Data from these two phases has been analyzed within the theoretical framework of sociocultural learning theory, arguing that this framework provides a description of the scaffolding process, which is fundamental to learning. Data from this phase is analyzed for mediation, contingency, the scaffolding steps, and the father's role as the teacher in the ZPD. However, data from the independent construction phase focuses on the language skills the children have independently produced, when the scaffolding has been removed. Language in this phase has been described and analyzed within the theoretical framework of systemic functional linguistics, arguing that this framework provides a systematic description of the children's conversational language. Data from this phase is analyzed for generic structure, mood and appraisal. The data set has been collected at random over a four year period. This focuses on the father's explicit teaching of five genres of casual conversation to his two daughters. The data set has been taken from the periods of explicit teaching, which occurs at set times of the day, mainly during 'dinner time talk', 'bed time talk', and 'before school study time'. In order to investigate the two aims of the thesis, the research questions focus on two main areas - questions related to the development of language skills, and questions related to the learning process. The four research questions related to the development of language skills are: • What is the extent to which the children can independently construct texts with appropriate generic structure? • What is the extent to which the children can structure their texts to reflect their speaking purposes? • What is the extent to which the children can give and exchange information appropriately within the five genres, using the interpersonal resources of mood? • What is the extent to which the children can express attitudes and take a stance by using the interpersonal resources of appraisal? The four research questions related to the learning process are: • What is the role of scaffolding in the children's learning? • What is the role of mediation in the children's learning? • What is the role of contingency in the children's learning? • What is the role of the teacher in the children's learning? The results of the study are based on the data findings in chapters 4, 5, and 6. Each text is analyzed and the findings are interpreted. Conclusions are then presented for each genre, and discussed in relation to the children's language skills and learning processes. The main conclusions of the thesis, incorporating all five genres, are presented in the final chapter. The significance of the thesis is discussed in terms of its implications for the fields of linguistics, second and foreign language education, and bilingualism. In terms of linguistics, it is argued that the thesis contributes to the descriptions and theorizing of casual conversation; for second and foreign language education, it illustrates the need for pedagogy to be based on functional and explicit theories of language and learning; and for bilingualism, it focuses on the importance of models in the development of identity. It is argued that the thesis makes a multidisciplinary contribution to each of these three academic fields. Also, by adopting an integrated theoretical stance to the data analysis, the thesis highlights the importance of providing different but complementary insights into the discourses of foreign language learning. These contributions reflect the significance of the thesis, which aims to merge language theory with learning pedagogy, relevant to children learning conversational English in a foreign language context

Applicazioni green alla conversione di oli di origine biologica

Questa tesi di dottorato si concentra sullo sviluppo di catalizzatori innovativi per la deossigenazione catalitica (DO) di oli vegetali, con l'obiettivo di produrre green diesel, un biocarburante sostenibile in grado di sostituire il petrodiesel convenzionale. Considerando l'urgenza di ridurre le emissioni di gas serra e raggiungere la neutralità carbonica, la ricerca esplora soluzioni economiche e rispettose dell'ambiente per superare i limiti del biodiesel, come l'elevato contenuto di ossigeno e la scarsa stabilità. Sono stati studiati tre catalizzatori principali: NiCoMo e ZnCoMo, replicati dalla letteratura, e un nuovo catalizzatore Ni-Mo-Al, sviluppato senza solventi secondo i principi della "Chimica Verde". La caratterizzazione dei catalizzatori è stata effettuata con tecniche avanzate e i test sperimentali sono stati condotti utilizzando un mini-reattore batch PARR®, analizzando parametri come temperatura, rapporto catalizzatore/olio, tempo di reazione e velocità di agitazione. I risultati hanno dimostrato che i catalizzatori NiCoMo e ZnCoMo sono stabili ed efficienti, con ZnCoMo che mostra una leggera superiorità in attività e stabilità. Il catalizzatore Ni-Mo-Al ha evidenziato un'elevata attività catalitica anche senza pre-riduzione, suggerendo un meccanismo di autoriduzione. Tutti i catalizzatori hanno mantenuto alte prestazioni per quattro cicli consecutivi. Lo studio ha identificato la temperatura, il rapporto catalizzatore/olio e il tempo di reazione come fattori chiave per ottimizzare il processo DO e ha dimostrato il potenziale industriale dei catalizzatori esaminati. I risultati forniscono una base per migliorare l'efficienza dei catalizzatori e avanzare verso la produzione di carburanti sostenibili

Research Abstract: From Description to Practice

The purpose of this paper is to show how university students for whom English is a foreign language can be taught to write an abstract for a research paper. The paper draws on research from Systemic Functional Linguistics, in particular from genre theory (Martin, 1985; Martin & Rose, 2003; Swales, 1990; 2004; Swales & Freak, 2004; Freak & Swales, 2011). A genre-based rating scale is described that makes explicit the specific functions of each section of the abstract. Data from two student abstracts are then analyzed and interpreted, illustrating how the theory has been applied

Coupled swelling and nematic reordering in liquid crystal gels

We derive a multiphysics model that accounts for network elasticity with spontaneous strains, swelling and nematic interactions in liquid crystal gels (LCGs). We discuss the coupling among the various physical mechanisms, with particular reference to the effects of nematic interactions on chemical equilibrium and that of swelling on the nematic-isotropic transition. Building upon this discussion and using numerical simulations, we explore the transient phenomena involving concurrent swelling and phase transition in LCGs subject to a temperature change. Specifically, we demonstrate separation in time scales between solvent uptake and phase change, in agreement with experiments, which determines a kinetic decoupling between shape and volume changes. Finally, we discuss possible applications in the context of microswimmers, where such a kinetic decoupling is exploited to achieve non-reciprocal actuation and net motion in Stokes flow

Concurrent factors determine toughening in the hydraulic fracture of poroelastic composites

Brittle materials fail catastrophically. In consequence of their limited flaw-tolerance, failure occurs by localized fracture and is typically a dynamic process. Recently, experiments on epithelial cell monolayers have revealed that this scenario can be significantly modified when the material susceptible to cracking is adhered to a hydrogel substrate. Thanks to the hydraulic coupling between the brittle layer and the poroelastic substrate, such a composite can develop a toughening mechanism that relies on the simultaneous growth of multiple cracks. Here, we study this remarkable behaviour by means of a detailed model, and explore how the material and loading parameters concur in determining the macroscopic toughness of the system. By extending a previous study, our results show that rapid loading conveys material toughness by promoting distributed cracking. Moreover, our theoretical findings may suggest innovative architectures of flaw-insensitive materials with higher toughness. ArXI

Swelling dynamics of a thin elastomeric sheet under uniaxial pre--stretch

It has been demonstrated experimentally that pre-stretch affects the swelling of an elastomeric membrane when it is exposed to a solvent. We study theoretically the one-dimensional swelling of a pre-stretched thin elastomeric sheet, bonded to an impermeable rigid substrate, to quantify the influence of pre-stretch. We show that the solvent uptake increases when pre-stretch increases, both at equilibrium and during the swelling transient, where it exhibits two different scaling regimes. The coupling between the solvent uptake and pre-stretch may be practically exploited to design soft actuators where the swelling-induced deformations can be controlled by varying the pre-stretch

Equilibrium and transient response of photo-actuated Liquid Crystal Elastomer beams

Light actuation is one of the preferred and advantageous approaches to remotely induce and control deformations in soft materials such as photoactive Liquid Crystal Elastomers (LCEs). Various experimental and numerical works have been carried out in the literature to study the actuation of photoactive LCE sheets under illumination. In this study, we have developed a reduced multi-physics model to predict the equilibrium and dynamic response of photoactive LCE beams under illumination. We test our model against an experiment in which a double-clamped thin nematic LCE beam is subjected to UV light, and the stress is generated in the beam due to induced contraction under illumination. Our numerical results demonstrate reasonable agreement with the experiment regarding stress evolution trend and saturation time. We also investigate the bending response of a photoactive LCE beam subjected to UV light. Based on our parameters, we observe that the nematic beam bends towards the light only due to the photochemical strain gradient along the thickness. Finally, to test our model in a dynamic situation, we perform the simulation for the self-oscillations of an LCE beam under illumination. We show that the alternate activation of the top and bottom surfaces of the LCE beam by uniform steady illumination can pump energy into the system, resulting in the phenomenon of self-oscillations

To What Extent Implanting Single vs Pairs of Magnets Per Muscle Affect the Localization Accuracy of the Myokinetic Control Interface? Evidence From a Simulated Environment

Objective: We recently proposed a new concept of human-machine interface to control hand prostheses which we dubbed the myokinetic control interface. Such interface detects muscle displacement during contraction by localizing permanent magnets implanted in the residual muscles. So far, we evaluated the feasibility of implanting one magnet per muscle and monitoring its displacement relative to its initial position. However, multiple magnets could actually be implanted in each muscle, as using their relative distance as a measure of muscle contraction could improve the system robustness against environmental disturbances. Methods: Here, we simulated the implant of pairs of magnets in each muscle and we compared the localization accuracy of such system with the one magnet per muscle approach, considering first a planar and then an anatomically appropriate configuration. Such comparison was also performed when simulating different grades of mechanical disturbances applied to the system (i.e., shift of the sensor grid). Results: We found that implanting one magnet per muscle always led to lower localization errors under ideal conditions (i.e., no external disturbances). Differently, when mechanical disturbances were applied, magnet pairs outperformed the single magnet approach, confirming that differential measurements are able to reject common mode disturbances. Conclusion: We identified important factors affecting the choice of the number of magnets to implant in a muscle. Significance: Our results provide important guidelines for the design of disturbance rejection strategies and for the development of the myokinetic control interface, as well as for a whole range of biomedical applications involving magnetic tracking