305 resultados para Charge dipole interaction


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Purpose – This chapter examines an episode of pretend play amongst a group of young girls in an elementary school in Australia, highlighting how they interact within the membership categorization device ‘family’ to manage their social and power relationships. Approach – Using conversation analysis and membership categorization analysis, an episode of video-recorded interaction that occurs amongst a group of four young girls is analyzed. Findings – As disputes arise amongst the girls, the mother category is produced as authoritative through authoritative actions by the girl in the category of mother, and displays of subordination on the part of the other children, in the categories of sister, dog and cat. Value of paper – Examining play as a social practice provides insight into the social worlds of children. The analysis shows how the children draw upon and co-construct family-style relationships in a pretend play context, in ways that enable them to build and organize peer interaction. Authority is highlighted as a joint accomplishment that is part of the social and moral order continuously being negotiated by the children. The authority of the mother category is produced and oriented to as a means of managing the disputes within the pretend frame of play.

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Under seismic loads neither the response of the pile nor the response of ground are independent of each other, contrary what is normally assumed. In seismic design of buildings, dynamic response of a structure is determined by assuming a fixed base on sub-grade and neglecting the physical interaction between foundation and soil profile in which it is embedded. However, the seismic response of pile foundations in vibration sensitive soil profiles is significantly affected by the behaviour of supporting soil. This research uses validated Finite Element techniques to simulate the seismic behaviour of pile foundations embedded in multilayered vibration sensitive soils.

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A wide variety of experiments that involve the physics of small particles (μm to cm in size) of planetary significance can be conducted on the Space Station. Processes of interest include nucleation and condensation of particles from a gas, aggregation of small particles into larger ones, and low velocity collisions of particles. Only experiments relevant to planetary processes will be discussed in detail here.

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This study investigates the development of teacher identity in a transnational context through an analysis of the voices of sixteen preservice teachers from Hong Kong who engage in interaction with primary students in an Australian classroom. The context for this research is the school-based experience undertaken by these preservice English as a second language teachers as part of their short language immersion (SLIM) program in Brisbane, Australia. Such SLIM programs are a genre of study abroad programs which have been gaining in popularity within teacher education in Australia, attended by preservice and inservice teachers from China, Hong Kong, Korea, and other Asian countries. This research is conducted at a time when the imperative to globalise higher education provision is a strategic factor in the educational policies of both Australia and Hong Kong. In Australia, international educational services now constitute the country’s third largest export with more than 400,000 students coming to Australia to study annually. In order to maintain Australia’s current global position as the third most popular Englishspeaking study destination, the government is now focusing on sustainability and the quality of the study experience being offered to international students (Bradley Review, 2008). In Hong Kong, the government sponsors both preservice and inservice English as a second language (ESL) teachers to undertake SLIM programs in Australia and other English-speaking countries, as part of their policy of promoting high levels of English proficiency in Hong Kong classrooms. Transnational teacher education is an important issue to which this study contributes insights into the affordances and constraints of a school-based experience in the transnational context. Second language teacher education has been defined as interventions designed to develop participants’ professional knowledge. In this study, it is argued that participation in a different community of practice helps to foreground tacit theories of second language pedagogy, making them visible and open to review. Questions of pedagogy are also seen as questions of teacher identity, constituting the way that one is in the classroom. I take up a sociocultural and poststructural framework, drawing on the work of James Gee and Mikhail Bakhtin, to theorise the construction of teacher identity as emerging through dialogic relations and socially situated discursive practices. From this perspective, this study investigates whether these teachers engage with different ways of representing themselves through appropriating, adapting or rejecting Discourses prevailing in the Australian classroom. Research suggests that reflecting on dilemmas encountered as lived experiences can extend professional understandings. In this study, the participants engage in a process of dialogic reflection on their intercultural classroom interactions, examining with their peers and their lecturer/researcher selected moments of dissonance that they have faced in the unfamiliar context of an Australian primary classroom. It is argued that the recursive and multivoiced nature of this process of reflection on practice allows participants opportunities to negotiate new understandings of second language teacher identity. Dialogic learning, based on the theories of Bakhtin and Vygotsky, provides the theoretic framing not only for the process of reflection instantiated in this study, but also features in the analysis of the participants’ second language classroom practices. The research design uses a combined discourse analytic and ethnographic approach as a logic-of-inquiry to explore the dialogic relationships which these second language teachers negotiate with their students and their peers in the transnational context. In this way, through discourse analysis of their classroom talk and reflective dialogues, assisted by the analytic tools of speech genres and discourse formats, I explore the participants’ ways of doing and being second language teachers. Thus, this analysis traces the process of ideological becoming of these beginner teachers as shifts in their understandings of teacher and student identities. This study also demonstrates the potential for a nontraditional stimulated recall interview to provide dialogic scaffolding for beginner teachers to reflect productively on their practice.

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Opening up a band gap and finding a suitable substrate material are two big challenges for building graphene-based nanodevices. Using state-of-the-art hybrid density functional theory incorporating long range dispersion corrections, we investigate the interface between optically active graphitic carbon nitride (g-C3N4) and electronically active graphene. We find an inhomogeneous planar substrate (g-C3N4) promotes electronrich and hole-rich regions, i.e., forming a well-defined electron−hole puddle, on the supported graphene layer. The composite displays significant charge transfer from graphene to the g-C3N4 substrate, which alters the electronic properties of both components. In particular, the strong electronic coupling at the graphene/g-C3N4 interface opens a 70 meV gap in g-C3N4-supported graphene, a feature that can potentially allow overcoming the graphene’s band gap hurdle in constructing field effect transistors. Additionally, the 2-D planar structure of g-C3N4 is free of dangling bonds, providing an ideal substrate for graphene to sit on. Furthermore, when compared to a pure g-C3N4 monolayer, the hybrid graphene/g-C3N4 complex displays an enhanced optical absorption in the visible region, a promising feature for novel photovoltaic and photocatalytic applications.

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We demonstrated for the first time by large-scale ab initio calculations that a graphene/titania interface in the ground electronic state forms a charge-transfer complex due to the large difference of work functions between graphene and titania, leading to substantial hole doping in graphene. Interestingly, electrons in the upper valence band can be directly excited from graphene to the conduction band, that is, the 3d orbitals of titania, under visible light irradiation. This should yield well-separated electron−hole pairs, with potentially high photocatalytic or photovoltaic performance in hybrid graphene and titania nanocomposites. Experimental wavelength-dependent photocurrent generation of the graphene/titania photoanode demonstrated noticeable visible light response and evidently verified our ab initio prediction.

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The interaction of bare graphene nanoribbons (GNRs) was investigated by ab initio density functional theory calculations with both the local density approximation (LDA) and the generalized gradient approximation (GGA). Remarkably, two bare 8-GNRs with zigzag-shaped edges are predicted to form an (8, 8) armchair single-wall carbon nanotube (SWCNT) without any obvious activation barrier. The formation of a (10, 0) zigzag SWCNT from two bare 10-GNRs with armchair-shaped edges has activation barriers of 0.23 and 0.61 eV for using the LDA and the revised PBE exchange correlation functional, respectively, Our results suggest a possible route to control the growth of specific types SWCNT via the interaction of GNRs.

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In i6 families, half of which had an alcoholic parent, both parents and an adolescent were videotaped interacting with each other. Mothers, fathers and the adolescent in each family viewed the videotaped interaction and completed ratings of themselves and the other two family members on levels of anxiety, involvement, dominance and friendliness. In families with an alcoholic parent, adolescents and their mothers rated family members as less anxious than did adolescents and mothers in families without a drinking problem. Also mothers in the alcoholic families rated family members as being more involved, and their ratings were higher than mothers in other families. Alcoholic families rated parent-adolescent interactions as more dominant and friendlier. At least in these videotaped interactions where alcohol was not being consumed, mothers in alcoholic families adopted a more positive view of family members than mothers in other families. In addition, possibly due to the efforts of fathers not to drink and memories of interactions when he was drunk, alcoholic families perceived their family interactions as more dominant and friendlier than families without an alcohol-related problem. [Schweitzer R, Wilks j, Callan vJ. Alcoholism and family interaction.

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In this thesis, I contribute to the study of how arrangements are made in social interaction. Using conversation analysis, I examine a corpus of 375 telephone calls between employees and clients of three Community Home Care (CHC) service agencies in metropolitan Adelaide, South Australia. My analysis of the CHC data corpus draws upon existing empirical findings within conversation analysis in order to generate novel findings about how people make arrangements with one another, and some of the attendant considerations that parties to such an activity can engage in: Prospective informings as remote proposals for a future arrangement – Focusing on how employees make arrangements with clients, I show how the employees in the CHC data corpus use ‘prospective informings’ to detail a future course of action that will involve the recipient of that informing. These informings routinely occasion a double-paired sequence, where informers pursue a response to their informing. This pursuit often occurs even after recipients have provided an initial response. This practice for making arrangements has been previously described by Houtkoop (1987) as ‘remote proposing.’ I develop Houtkoop’s analysis to show how an informing of a future arrangement can be recompleted, with response solicitation, as a proposal that is contingent upon a recipient’s acceptance. Participants’ understanding of references to non-present third parties – In the process of making arrangements, references are routinely made to non-present third parties. In the CHC data corpus, these third parties are usually care workers. Prior research (e.g., Sacks & Schegloff, 1979; Schegloff, 1996b) explains how the use of ‘recognitional references’ (such as the bare name ‘Kerry’), conveys to recipients that they should be able to locate the referent from amongst their acquaintances. Conversely, the use of ‘non-recognitional references’ (such as the description ‘a lady called Kerry’), conveys that recipients are unacquainted with the referent. I examine instances where the selection of a recognitional or non-recognitional reference form is followed by a recipient initiating repair on that reference. My analysis provides further evidence thatthe existing analytic account of these references corresponds to the way in which participants themselves make sense of them. My analysis also advances an understanding of how repair can be used, by recipients, to indicate the inappositeness of a prior turn. Post-possible-completion accounts – In a case study of a problematic interaction, I examine a misunderstanding that is not resolved within the repair space, the usual defence of intersubjectivity in interaction (cf. Schegloff, 1992b). Rather, I explore how the source of trouble is addressed, outside of the sequence of its production, with a ‘post-possible-completion account.’ This account specifies the basis of a misunderstanding and yet, unlike repair, does so without occasioning a revised response to a trouble-source turn. By considering various aspects of making arrangements in social interaction, I highlight some of the rich order that underpins the maintenance of human relationships across time. In the concluding section of this thesis I review this order, while also discussing practical implications of this analysis for CHC practice.

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This study investigates the time-course and post-receptoral pathway signaling of photoreceptor interactions when the rod (R) and three cone (L, M, S) photoreceptor classes contribute to mesopic vision. A four-primary photostimulator independently controls photoreceptor activity in human observers. The first experiment defines the temporal adaptation response of receptoral (L-, S-cone, rod) and post-receptoral (LMS, LMSR,+L-M) signaling and interactions. Here we show that nonopponent cone-cone interactions (L-cone, LMS, LMSR) have monophasic temporal response patterns whereas opponent signals (+L-M, S-cone) show biphasic response patterns with slower recovery. By comparison, rod-cone interactions with nonopponent signals have faster adaptation responses and reduced sensitivity loss whereas opponent rod-cone interactions are small or absent. Additionally, the rod-rod interaction differs from these interaction types and acts to increase rod sensitivity due to temporal summation but with a slower time course. The second experiment shows that the temporal profile of the rod signal alters the relative rod contributions to the three primary post-receptoral pathways. We demonstrate that rod signals generate luminance (þLþM) signals mediated via the MC pathway with all rod temporal profiles and chromatic signals (L/LþM, S/LþM) in both the PC and KC pathways with durations .75 ms. Thus, we propose that the change in relative weighting of rod signals within the post-receptoral pathways contributes to the sensitivity and temporal response of rod and cone pathway signaling and interactions.

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Young adults represent the largest group of first time donors to the Australian Red Cross Blood Service, but they are also the least loyal group and often do not return after their first donation. At the same time, many young people use the internet and various forms of social media on a daily basis. Web and mobile based technological practices and communication patterns change the way that young people interact with one another, with their families, and communities. Combining these two points of departure, this study seeks to identify best practices of employing mobile apps and social media in order to enhance the loyalty rates of young blood donors. The findings reported in this paper are based on a qualitative approach presenting a nuanced understanding of the different factors that motivate young people to donate blood in the first place, as well as the obstacles or issues that prevent them from returning. The paper discusses work in progress with a view to inform the development of interactive prototypes trialling three categories of features: personal services (such as scheduling); social media (such as sharing the donation experience with friends to raise awareness); and data visualisations (such as local blood inventory levels). We discuss our translation of research findings into design implications.

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This paper reports the results of a mixed method approach to answer: To what extent do cultural values impact on e-service use in Saudi Arabia, and if so how? This paper will firstly, introduce the importance of culture and define the aspects of Saudi culture with focus on our scope: the fear of a lack of Interaction with other Humans. It will then describe the method used and present the qualitative and quantitative findings related to the need for Interactions with other Humans. Much of the written literature about human interaction aims at Information Systems design or design improvement. Yet, this is different to what is being investigated in this study. One of the factors this study will consider is the perceived lack of interaction with other humans or the anxiety people may feel in missing the physical interaction with other people by fully moving business interaction to the virtual world. The review of the literature indicates that the impact of such factor on Information and Communication Technologies (ICT) use has not been studied. This research aims to cover this gap by investigating to what extent the fear of a lack of Interaction with other Humans, as one of Saudi Arabia’s cultural values, impacts on e-service use in Saudi Arabia. The tested hypothesis was found consistent with its predicted outcome: the fear of a lack of Interaction with other Humans is a negative predictor of intention to use e-services in Saudi Arabia. It is evidenced that consideration of the impact of the cultural values will mainly contribute to the enhancement of ICTs implementation and use.

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A key issue in the field of inclusive design is the ability to provide designers with an understanding of people's range of capabilities. Since it is not feasible to assess product interactions with a large sample, this paper assesses a range of proxy measures of design-relevant capabilities. It describes a study that was conducted to identify which measures provide the best prediction of people's abilities to use a range of products. A detailed investigation with 100 respondents aged 50-80 years was undertaken to examine how they manage typical household products. Predictor variables included self-report and performance measures across a variety of capabilities (vision, hearing, dexterity and cognitive function), component activities used in product interactions (e.g. using a remote control, touch screen) and psychological characteristics (e.g. self-efficacy, confidence with using electronic devices). Results showed, as expected, a higher prevalence of visual, hearing, dexterity, cognitive and product interaction difficulties in the 65-80 age group. Regression analyses showed that, in addition to age, performance measures of vision (acuity, contrast sensitivity) and hearing (hearing threshold) and self-report and performance measures of component activities are strong predictors of successful product interactions. These findings will guide the choice of measures to be used in a subsequent national survey of design-relevant capabilities, which will lead to the creation of a capability database. This will be converted into a tool for designers to understand the implications of their design decisions, so that they can design products in a more inclusive way.

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In this paper we describe tag-based interaction afforded by a tag-based interface in online and mobile banking, and present our preliminary usability evaluation findings. We conducted a pilot usability study with a group of banking users by comparing the present 'conventional' interface and tag-based interface. The results show that participants perceive the tag-based interface as more usable in both online and mobile contexts. Participants also rated the tag-based interface better despite their unfamiliarity and perceived it as more user-friendly. Additionally, the results highlight that tag-based interaction is more effective in the mobile context especially to inexperienced mobile banking users. This in turn could have a positive effect on the adoption and acceptance of mobile banking in general and also specifically in Australia. We discuss our findings in more detail in the later sections of this paper and conclude with a discussion on future work.

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The practical number of charge carriers loaded is crucial to the evaluation of the capacity performance of carbon-based electrodes in service, and cannot be easily addressed experimentally. In this paper, we report a density functional theory study of charge carrier adsorption onto zigzag edge-shaped graphene nanoribbons (ZGNRs), both pristine and incorporating edge substitution with boron, nitrogen or oxygen atoms. All edge substitutions are found to be energetically favorable, especially in oxidized environments. The maximal loading of protons onto the substituted ZGNR edges obeys a rule of [8-n-1], where n is the number of valence electrons of the edge-site atom constituting the adsorption site. Hence, a maximum charge loading is achieved with boron substitution. This result correlates in a transparent manner with the electronic structure characteristics of the edge atom. The boron edge atom, characterized by the most empty p band, facilitates more than the other substitutional cases the accommodation of valence electrons transferred from the ribbon, induced by adsorption of protons. This result not only further confirms the possibility of enhancing charge storage performance of carbon-based electrochemical devices through chemical functionalization but also, more importantly, provides the physical rationale for further design strategies.