876 research outputs found
Sustaining and Scaling Pedagogic Innovation in Sub-Saharan Africa: Grounded Insights For Teacher Professional Development
Developing sustainable and scalable educational initiatives is a key challenge in low-income countries where donor-funded short-term projects are limited by both contextual factors and programme design. In this concept paper we examine some of the issues related to in-service teacher development in the context of sub-Saharan Africa, grounded predominantly in our experiences of over 5 years of iteratively developing, refining and evaluating an intensive school-based professional learning programme for primary school teachers. “OER4Schools” integrates interactive pedagogy, Open Educational Resources (OER) and use of mobile devices (where available). The focus of this paper is on identifying what the main factors are perceived to be in sustaining and scaling up such a programme, from the perspectives of participating teachers, workshop facilitators and the research team. Synthesising our previous research and drawing on recent work in the field, we identify the key characteristics of effective and sustainable professional learning in low-resourced contexts. Such characteristics include effective peer facilitation, school-based active learning, explicit programme structure, appropriate scheduling and resourcing, and mitigating resource constraints through use of OER. Our conclusions thereby offer insights concerning the importance and impact of wider influences on participation and engagement of stakeholders and lead to recommendations for programme design and implementation, that should be taken on board by future initiatives
Climbing the Jaynes-Cummings Ladder and Observing its Sqrt(n) Nonlinearity in a Cavity QED System
The already very active field of cavity quantum electrodynamics (QED),
traditionally studied in atomic systems, has recently gained additional
momentum by the advent of experiments with semiconducting and superconducting
systems. In these solid state implementations, novel quantum optics experiments
are enabled by the possibility to engineer many of the characteristic
parameters at will. In cavity QED, the observation of the vacuum Rabi mode
splitting is a hallmark experiment aimed at probing the nature of matter-light
interaction on the level of a single quantum. However, this effect can, at
least in principle, be explained classically as the normal mode splitting of
two coupled linear oscillators. It has been suggested that an observation of
the scaling of the resonant atom-photon coupling strength in the
Jaynes-Cummings energy ladder with the square root of photon number n is
sufficient to prove that the system is quantum mechanical in nature. Here we
report a direct spectroscopic observation of this characteristic quantum
nonlinearity. Measuring the photonic degree of freedom of the coupled system,
our measurements provide unambiguous, long sought for spectroscopic evidence
for the quantum nature of the resonant atom-field interaction in cavity QED. We
explore atom-photon superposition states involving up to two photons, using a
spectroscopic pump and probe technique. The experiments have been performed in
a circuit QED setup, in which ultra strong coupling is realized by the large
dipole coupling strength and the long coherence time of a superconducting qubit
embedded in a high quality on-chip microwave cavity.Comment: ArXiv version of manuscript published in Nature in July 2008, 5
pages, 5 figures, hi-res version at
http://www.finkjohannes.com/SqrtNArxivPreprint.pd
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Developing a coding scheme for analysing classroom dialogue across d educational contexts.
The research reported sought to develop a framework for systematically analysing classroom dialogue for application across a range of educational settings. The paper outlines the development and refinement of a coding scheme that attempts to represent and operationalise commonalities amongst some key theorists in the field concerning productive forms of educational dialogue. The team has tested it using video recordings from classroom settings in the UK and Mexico, across age phases, subject areas, and different interactional contexts including whole class, group and paired work. Our Scheme for Educational Dialogue Analysis (SEDA) is situated within a sociocultural paradigm, and draws on Hymes' Ethnography of Communication to highlight the importance of context. We examined how such a tool could be used in practice. We found that concentrating on the ‘communicative act’ to explore dialogue between participants was an appropriate level of granularity, while clustering the 33 resulting codes according to function of the acts helped to highlight dialogic sequences within lessons. We report on the application of the scheme in two different learning contexts and reflect on its fitness for purpose, including perceived limitations. Development of specialised sub-schemes and a version for teachers is underway.This collaborative work was carried out for a project entitled “A Tool for Analysing Dialogic Interactions in Classrooms” (http://tinyurl.com/BAdialogue) funded through the British Academy International Partnership and Mobility Scheme (ref. RG66509), between January 2013 - December 2015. We are most grateful to colleagues on the project teams who made significant contributions and helpful input during development and testing of the scheme and preparation of the manuscript, including Farah Ahmed, Riikka Hofmann, Christine Howe, Ruth Kershner, Fiona Jackson, Karen Littleton, Neil Mercer, Paul Warwick (UK team); Mariana Alarcón, Nube Estrada, Erika Gil, Kissy Guzmán, Flora Hernández, José Hernández, Haydeé Pedraza, Ana Luisa Rubio, Brenda Itzel Sánchez, Ana Laura Trigo, Maricela Velez (Mexico team). We also thank all of the teachers (especially Lloyd and Tania) and students who participated in our previous research from which examples were taken. We appreciate the support of the Economic and Social Research Council, sponsor of most of the UK team’s work in this area over the years
Automated Analysis of Craniofacial Morphology Using Magnetic Resonance Images
Quantitative analysis of craniofacial morphology is of interest to scholars
working in a wide variety of disciplines, such as anthropology, developmental
biology, and medicine. T1-weighted (anatomical) magnetic resonance images (MRI)
provide excellent contrast between soft tissues. Given its three-dimensional
nature, MRI represents an ideal imaging modality for the analysis of
craniofacial structure in living individuals. Here we describe how T1-weighted
MR images, acquired to examine brain anatomy, can also be used to analyze facial
features. Using a sample of typically developing adolescents from the Saguenay
Youth Study (N = 597; 292 male, 305 female, ages: 12 to 18
years), we quantified inter-individual variations in craniofacial structure in
two ways. First, we adapted existing nonlinear registration-based morphological
techniques to generate iteratively a group-wise population average of
craniofacial features. The nonlinear transformations were used to map the
craniofacial structure of each individual to the population average. Using
voxel-wise measures of expansion and contraction, we then examined the effects
of sex and age on inter-individual variations in facial features. Second, we
employed a landmark-based approach to quantify variations in face surfaces. This
approach involves: (a) placing 56 landmarks (forehead, nose, lips, jaw-line,
cheekbones, and eyes) on a surface representation of the MRI-based group
average; (b) warping the landmarks to the individual faces using the inverse
nonlinear transformation estimated for each person; and (3) using a principal
components analysis (PCA) of the warped landmarks to identify facial features
(i.e. clusters of landmarks) that vary in our sample in a correlated fashion. As
with the voxel-wise analysis of the deformation fields, we examined the effects
of sex and age on the PCA-derived spatial relationships between facial features.
Both methods demonstrated significant sexual dimorphism in craniofacial
structure in areas such as the chin, mandible, lips, and nose
Applications of Fair Testing
In this paper we present the application of the fair testing pre-order, introduced in a previous paper, to the specification and analysis of distributed systems. This pre-order combines some features of the standard testing pre-orders, viz. the possibility to refine a specification by the resolution of nondeterminism, with a powerful feature of standard observation congruence, viz. the fair abstraction from divergences. Moreover, it is a pre-congruence with respect to all standard process-algebraic combinators, thus allowing for the standard algebraic proof techniques by substitution and rewriting. In this paper we will demonstrate advantages of the fair testing pre-order by the application to a number of examples, including a scheduling problem, a version of the Alternating Bit-protocol, and fair communication channels
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A scalable expressive ensemble learning using Random Prism: a MapReduce approach
The induction of classification rules from previously unseen examples is one of the most important data mining tasks in science as well as commercial applications. In order to reduce the influence of noise in the data, ensemble learners are often applied. However, most ensemble learners are based on decision tree classifiers which are affected by noise. The Random Prism classifier has recently been proposed as an alternative to the popular Random Forests classifier, which is based on decision trees. Random Prism is based on the Prism family of algorithms, which is more robust to noise. However, like most ensemble classification approaches, Random Prism also does not scale well on large training data. This paper presents a thorough discussion of Random Prism and a recently proposed parallel version of it called Parallel Random Prism. Parallel Random Prism is based on the MapReduce programming paradigm. The paper provides, for the first time, novel theoretical analysis of the proposed technique and in-depth experimental study that show that Parallel Random Prism scales well on a large number of training examples, a large number of data features and a large number of processors. Expressiveness of decision rules that our technique produces makes it a natural choice for Big Data applications where informed decision making increases the user’s trust in the system
Provision of foot health services for people with rheumatoid arthritis in New South Wales: a web-based survey of local podiatrists
Background: It is unclear if podiatric foot care for people with rheumatoid arthritis (RA) in New South Wales (NSW) meets current clinical recommendations. The objective of this study was to survey podiatrists' perceptions of the nature of podiatric foot care provision for people who have RA in NSW.Methods: An anonymous, cross-sectional survey with a web-based questionnaire was conducted. The survey questionnaire was developed according to clinical experience and current foot care recommendations. State registered podiatrists practising in the state of NSW were invited to participate. The survey link was distributed initially via email to members of the Australian Podiatry Association (NSW), and distributed further through snowballing techniques using professional networks. Data was analysed to assess significant associations between adherence to clinical practice guidelines, and private/public podiatry practices.Results: 86 podiatrists participated in the survey (78% from private practice, 22% from public practice). Respondents largely did not adhere to formal guidelines to manage their patients (88%). Only one respondent offered a dedicated service for patients with RA. Respondents indicated that the primary mode of accessing podiatry was by self-referral (68%). Significant variation was observed regarding access to disease and foot specific assessments and treatment strategies. Assessment methods such as administration of patient reported outcome measures, vascular and neurological assessments were not conducted by all respondents. Similarly, routine foot care strategies such as prescription of foot orthoses, foot health advice and footwear were not employed by all respondents.Conclusions: The results identified issues in foot care provision which should be explored through further research. Foot care provision in NSW does not appear to meet the current recommended standards for the management of foot problems in people who have RA. Improvements to foot care could be undertaken in terms of providing better access to examination techniques and treatment strategies that are recommended by evidence based treatment paradigms. © 2013 Hendry et al.; licensee BioMed Central Ltd
Transport spectroscopy of non-equilibrium many-particle spin states in self-assembled quantum dots
Self-assembled quantum dots (QDs) are prominent candidates for solid-state quantum information processing. For these systems, great progress has been made in addressing spin states by optical means. In this study, we introduce an all-electrical measurement technique to prepare and detect non-equilibrium many-particle spin states in an ensemble of self-assembled QDs at liquid helium temperature. The excitation spectra of the one- (QD hydrogen), two- (QD helium) and three- (QD lithium) electron configuration are shown and compared with calculations using the exact diagonalization method. An exchange splitting of 10 meV between the excited triplet and singlet spin states is observed in the QD helium spectrum. These experiments are a starting point for an all-electrical control of electron spin states in self-assembled QDs above liquid helium temperature
Engineering of quantum dot photon sources via electro-elastic fields
The possibility to generate and manipulate non-classical light using the
tools of mature semiconductor technology carries great promise for the
implementation of quantum communication science. This is indeed one of the main
driving forces behind ongoing research on the study of semiconductor quantum
dots. Often referred to as artificial atoms, quantum dots can generate single
and entangled photons on demand and, unlike their natural counterpart, can be
easily integrated into well-established optoelectronic devices. However, the
inherent random nature of the quantum dot growth processes results in a lack of
control of their emission properties. This represents a major roadblock towards
the exploitation of these quantum emitters in the foreseen applications. This
chapter describes a novel class of quantum dot devices that uses the combined
action of strain and electric fields to reshape the emission properties of
single quantum dots. The resulting electro-elastic fields allow for control of
emission and binding energies, charge states, and energy level splittings and
are suitable to correct for the quantum dot structural asymmetries that usually
prevent these semiconductor nanostructures from emitting polarization-entangled
photons. Key experiments in this field are presented and future directions are
discussed.Comment: to appear as a book chapter in a compilation "Engineering the
Atom-Photon Interaction" published by Springer in 2015, edited by A.
Predojevic and M. W. Mitchel
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