6,562 research outputs found
Self-tuned quantum dot gain in photonic crystal lasers
We demonstrate that very few (1 to 3) quantum dots as a gain medium are
sufficient to realize a photonic crystal laser based on a high-quality
nanocavity. Photon correlation measurements show a transition from a thermal to
a coherent light state proving that lasing action occurs at ultra-low
thresholds. Observation of lasing is unexpected since the cavity mode is in
general not resonant with the discrete quantum dot states and emission at those
frequencies is suppressed. In this situation, the quasi-continuous quantum dot
states become crucial since they provide an energy-transfer channel into the
lasing mode, effectively leading to a self-tuned resonance for the gain medium.Comment: 4 pages, 4 figures, submitted to Phys. Re
Inspiring to inspire: Developing teaching in higher education
Following a three-year staff development initiative within one faculty in a UK university, the authors reflected on inspiring teaching and the role that staff development can play in enhancing individual practice. Teaching is a core component of Higher Education and is complex and multi-faceted both theoretically and in practice. Through individual reflections to a set of pre-determined questions, a group of Higher Education teachers (n = 5) with a responsibility for the development of learning, teaching and assessment, share their thoughts, feelings and beliefs on inspiring teaching. The interpretive analysis of the data shows from a staff perspective that the notion of inspiring teaching has three main components which are all interrelated, those being; the actual teaching and learning experience; the design of the curriculum and the teacher/student relationship. Staff development initiatives were found to help people explore and develop their own teaching philosophy, to develop new practices and to share and learn from others. However, individualâs mindset, beliefs and attitudes were found to be a challenge. Teachers can frame their development around the different aspects of inspiring teaching and with support from senior leadership as well as a positive culture, teaching communities can work together towards inspiring teaching
A Flexible and Modular Framework for Implementing Infrastructures for Global Computing
We present a Java software framework for building infrastructures to support the development of applications for systems where mobility and network awareness are key issues. The framework is particularly useful to develop run-time support for languages oriented towards global computing. It enables platform designers to customize communication protocols and network architectures and guarantees transparency of name management and code mobility in distributed environments. The key features are illustrated by means of a couple of simple case studies
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TeacherâStudent Dialogue During Classroom Teaching: Does It Really Impact on Student Outcomes?
It is now widely believed that classroom dialogue matters as regards student outcome, with optimal patterns often regarded as requiring some or all of: open questions; elaboration of previous contributions; reasoned discussion of competing viewpoints; linkage and coordination across contributions; meta-cognitive engagement with dialogue; high student participation. To date however, the relevance of such features has been most convincingly examined in relation to small-group interaction amongst students; little is known about applicability to teacher-student dialogue. The paper reports a large-scale study that permits some rebalancing. The study revolves around the two lessons (covering two of mathematics, literacy and science) that were video-recorded in each of 72 demographically diverse classrooms (students aged 10-11 years). Key measures of teacher-student dialogue were related to six indices of student outcome, which jointly covered curriculum mastery, reasoning, and educationally relevant attitudes. Prior attainment and attitudes were considered in analyses as were other factors, e.g. student demographics and further aspects of classroom practice, that might confound interpretation of dialogue-outcome relations. So long as students participated extensively, elaboration and querying of previous contributions were found to be positively associated with curriculum mastery, and elaboration was also positively associated with attitudes.ESR
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Dialogic practices in primary school classrooms
Research into classroom dialogue suggests that certain forms are especially productive for studentsâ learning (Howe and Abedin, 2013). Despite the large number of studies in this area, there is inadequate evidence about the prevalence of the identified forms, let alone their productivity. However, scarcity is widely presumed. The overall aim of the study reported in this paper was to examine the extent to which the forms are embedded within current practice in UK primary schools. Video-recordings of two lessons from each of 36 classrooms formed the database, with two subjects from mathematics, English and science covered in each classroom. Each lesson was coded per turn for the presence of âdialogic movesâ and rated overall for the level of student involvement in specified activities. Results revealed that the supposedly productive forms were not always as scarce as sometimes presumed, while also highlighting huge variation in their relative occurrence. They also point to the role of professional development for teachers in promoting use of some forms
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Safe and effective prescribing with dyslexia
Background: The term âdyslexiaâ refers to a condition that impacts upon reading and writing abilities whilst not altering intelligence. Individuals with dyslexia may have difficulties with the speed and accuracy and their reading and writing, amongst other issues. Dyslexia is not automatically considered a disability but is a protected characteristic under the UK Equality Act (2010), and therefore employers and educational institutions are required to provide âreasonable adjustmentsâ in order to allow individuals to reach their full potential. There is a lack of research on this issue, but what little there is suggests that doctors feel as though any support they received ended when they graduated from medical school.
Main body: A core distinction between medical school and medical practice is the requirement to prescribe medicines as registered medical practitioners. Junior doctors have to master this complex and potentially hazardous skill âon the jobâ, with a perceived lack of support. Here, we open up a debate about the potential impact of dyslexia on prescribing, and the need to find supports that may be effective in enabling doctors with dyslexia prescribe medicines safely and effectively â and thus reach their full potential as medical practitioners and promote patient safety.
Conclusion: We argue that medical schools and hospitals could immediately provide dyslexia awareness training in both undergraduate and postgraduate settings. We discuss electronic prescribing systems, and conclude that research is required to identify effective supports for junior doctors with dyslexia
Linearity in the non-deterministic call-by-value setting
We consider the non-deterministic extension of the call-by-value lambda
calculus, which corresponds to the additive fragment of the linear-algebraic
lambda-calculus. We define a fine-grained type system, capturing the right
linearity present in such formalisms. After proving the subject reduction and
the strong normalisation properties, we propose a translation of this calculus
into the System F with pairs, which corresponds to a non linear fragment of
linear logic. The translation provides a deeper understanding of the linearity
in our setting.Comment: 15 pages. To appear in WoLLIC 201
Effective representation of RT-LOTOS terms by finite time petri nets
The paper describes a transformational approach for the
specification and formal verification of concurrent and real-time systems. At upper level, one system is specified using the timed process algebra RT-LOTOS. The output of the proposed transformation is a Time Petri net (TPN). The paper particularly shows how a TPN can be automatically constructed from an RT-LOTOS specification using a compositionally defined mapping. The proof of the translation consistency is sketched in the paper and developed in [1]. The RT-LOTOS to TPN translation patterns formalized in the paper are being implemented. in a prototype tool. This enables reusing TPNs verification techniques and tools for the profit of RT-LOTOS
The training and development needs of nurses in Indonesia: paper 3 of 3
BACKGROUND: Indonesia's recent economic and political history has left a legacy of widespread poverty and serious health problems, and has contributed to marked inequalities in health care. One means of responding to these challenges has been through a reconsideration of the professional roles of nurses, to enable them to deal with the range and complexity of health problems. However, there are currently a number of obstacles to achieving these aims: there is a serious shortfall in trained nurses; the majority of nurses have only limited education and preparation for the role; and there is no central registration of nurses, which means that it is impossible to regulate either the profession or the standards of care. This study aimed to establish the occupational profiles of each grade of nurse, identify their training and development needs and ascertain whether any differences existed between nurses working in different regions or within hospital or community settings. METHODS: An established and psychometrically valid questionnaire was administered to 524 nurses, covering three grades and coming from five provinces. RESULTS: Significant differences in job profile were found in nurses from different provinces, suggesting that the nature of the role is determined to some degree by the geographical location of practice. The roles of hospital and community nurses, and the different grades of nurse, were fairly similar. All nurses reported significant training needs for all 40 tasks, although these did not vary greatly between grade of nurse. The training needs of nurses from each of the provinces were quite distinct, while those of hospital nurses were greater than those of community nurses. CONCLUSION: The results suggest that the role of the nurse is not as diverse as might be expected, given the different levels of preparation and training and the diversity of their work environments. This may reflect the lack of a central registration system and quality framework, which would normally regulate clinical activities according to qualifications. The differences in training needs between subsections of the sample highlight the importance of identifying skills deficits and using this information to develop customized post-registration education programmes. Together, these results provide a rigorous and reliable approach to defining the occupational roles and continuing education needs of Indonesian nurses
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