42,341 research outputs found
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A child-centred exploration of the relevance of family and friends to theory of mind development
This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2011 The Authors.Theory of Mind (ToM) is said to develop at around 4 years old. But some studies suggest it develops considerably earlier than this, with others suggesting it develops much later. Although several recent studies have found that social factors (like gender, family size, number of siblings, and number of friends) can impact on ToM, other studies contradict those findings. We wondered whether addressing several procedural issues and ensuring the task concerns real protagonists in real time, would bear on the above issues. Here, 114 children of 3–6 years completed four ToM tasks incorporating controls from experimental psychology, including randomly varying the order of ToM and non-ToM questions across participants. Now, children passed ToM tasks from around 5 years old, rather than 4 years or earlier. Girls did not develop ToM any earlier than boys. There was clear correlational evidence for the older-sibling effect and effects of friends but no reliable effects of nuclear or extended family. However, when these factors were set in the context of one another, the sibling effect was driven by a negative influence from younger siblings (as opposed to older siblings) and the friends effect was driven by friends at school (as opposed to friends at home). Finally, “friends” was a stronger predictor than siblings but memory (a cognitive factor) and age (a maturational factor) were the strongest predictors of all
Factors and processes in children's transitive deductions
Transitive tasks are important for understanding how children develop socio-cognitively. However, developmental research has been restricted largely to questions surrounding maturation. We asked 6-, 7- and 8-year-olds (N = 117) to solve a composite of five different transitive tasks. Tasks included conditions asking about item-C (associated with the marked relation) in addition to the usual case of asking only about item-A (associated with the unmarked relation). Here, children found resolving item-C much easier than resolving item-A, a finding running counter to long-standing assumptions about transitive reasoning. Considering gender perhaps for the first time, boys exhibited higher transitive scores than girls overall. Finally, analysing in the context of one recent and well-specified theory of spatial transitive reasoning, we generated the prediction that reporting the full series should be easier than deducing any one item from that series. This prediction was not upheld. We discuss amendments necessary to accommodate all our earlier findings
Simulation analysis of the consequences of shifting the balance of health care: a system dynamics approach
Objectives: The shift in the balance of health care, bringing services 'closer to home', is a well-established trend. This study sought to provide insight into the consequences of this trend, in particular the stimulation of demand, by exploring the underlying feedback structure.
Methods: We constructed a simulation model using the system dynamics method, which is specifically designed for the analysis of feedback structure. The model was calibrated to two cases of the shift in cardiac catheterization services in the UK. Data sources included archival data, observations and interviews with senior health care professionals. Key model outputs were the basic trends displayed by waiting lists, average waiting times, cumulative patient referrals, cumulative patient activity and cumulative overall costs.
Results: Demand was stimulated in both cases via several different mechanisms. We revealed the roles for clinical guidelines and capacity changes, and the typical responses to imbalances between supply and demand. Our analysis also demonstrated the potential benefits of changing the goals that drive activity by seeking a waiting list goal rather than a waiting time goal.
Conclusions: Appreciating the wider consequences of shifting the balance of care is essential if services are to be improved overall. The underlying feedback mechanisms of both intended and unintended effects need to be understood. Using a systemic approach, more effective policies may be designed through coordinated programmes rather than isolated initiatives, which may have only a limited impact
Intercalation events visualized in single microcrystals of graphite.
The electrochemical intercalation of layered materials, particularly graphite, is fundamental to the operation of rechargeable energy-storage devices such as the lithium-ion battery and the carbon-enhanced lead-acid battery. Intercalation is thought to proceed in discrete stages, where each stage represents a specific structure and stoichiometry of the intercalant relative to the host. However, the three-dimensional structures of the stages between unintercalated and fully intercalated are not known, and the dynamics of the transitions between stages are not understood. Using optical and scanning transmission electron microscopy, we video the intercalation of single microcrystals of graphite in concentrated sulfuric acid. Here we find that intercalation charge transfer proceeds through highly variable current pulses that, although directly associated with structural changes, do not match the expectations of the classical theories. Evidently random nanoscopic defects dominate the dynamics of intercalation
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Electron beam-induced current imaging with two-angstrom resolution.
An electron microscope's primary beam simultaneously ejects secondary electrons (SEs) from the sample and generates electron beam-induced currents (EBICs) in the sample. Both signals can be captured and digitized to produce images. The off-sample Everhart-Thornley detectors that are common in scanning electron microscopes (SEMs) can detect SEs with low noise and high bandwidth. However, the transimpedance amplifiers appropriate for detecting EBICs do not have such good performance, which makes accessing the benefits of EBIC imaging at high-resolution relatively more challenging. Here we report lattice-resolution imaging via detection of the EBIC produced by SE emission (SEEBIC). We use an aberration-corrected scanning transmission electron microscope (STEM), and image both microfabricated devices and standard calibration grids
Psychosocial factors and work related sickness absence among permanent and non-permanent employees
Study objective: To examine the association between psychosocial work factors and work related sickness absence among permanent and non-permanent employees by sex.Design: A cross sectional survey conducted in 2000 of a representative sample of the European Union total active population, aged 15 years and older. The independent variables were psychological job demands and job control as measures of psychosocial work environment, and work related sickness absence as the main outcome. Poisson regression models were used to compute sickness absence days' rate ratios.Setting: 15 countries of the European Union.Participants: A sample of permanent (n=12875) and non-permanent (n=1203) workers from the Third European Survey on Working Conditions.Results: High psychological job demands, low job control, and high strain and passive work were associated with higher work related sickness absence. The risks were more pronounced in non-permanent compared with permanent employees and men compared with women.Conclusions: This work extends previous research on employment contracts and sickness absence, suggesting different effects depending on psychosocial working conditions and sex
Incorporating remote visits into an outpatient clinic
Copyright @ 2009 Operational Research Society Ltd. This is a post-peer-review, pre-copyedit version of an article published in Journal of Simulation. The definitive publisher-authenticated version Eatock and Eldabi (2009), "Incorporating remote visits into an outpatient clinic", Journal of Simulation, 3, 179–188 is available online at the link below.Most telemedicine studies are concerned with either the technological or diagnostic comparisons, rather than assessing the impact on clinic management. This has attributed to the retrospective nature of the studies, with lack of data being the main cause for not using simulation for prospective analysis. This article demonstrates the use of simulation to assess the impact of prospective systems by utilising data generated from clinical trials. The example used here is the introduction of remote consultations into an outpatient's clinic. The article addresses the issues of using secondary data, in terms of the differences between the trial, the model and future reality. The result of running the simulation model show that exchanging the mode of service delivery does not improve patient wait times as expected, and that a protocol change in association with the introduction of remote visits is necessary to provide a substantial reduction in patient wait times
The impact of the ATLAS zero-lepton, jets and missing momentum search on a CMSSM fit
Recent ATLAS data significantly extend the exclusion limits for
supersymmetric particles. We examine the impact of such data on global fits of
the constrained minimal supersymmetric standard model (CMSSM) to indirect and
cosmological data. We calculate the likelihood map of the ATLAS search, taking
into account systematic errors on the signal and on the background. We validate
our calculation against the ATLAS determinaton of 95% confidence level
exclusion contours. A previous CMSSM global fit is then re-weighted by the
likelihood map, which takes a bite at the high probability density region of
the global fit, pushing scalar and gaugino masses up.Comment: 16 pages, 7 figures. v2 has bigger figures and fixed typos. v3 has
clarified explanation of our handling of signal systematic
Synthesis of Recursive ADT Transformations from Reusable Templates
Recent work has proposed a promising approach to improving scalability of
program synthesis by allowing the user to supply a syntactic template that
constrains the space of potential programs. Unfortunately, creating templates
often requires nontrivial effort from the user, which impedes the usability of
the synthesizer. We present a solution to this problem in the context of
recursive transformations on algebraic data-types. Our approach relies on
polymorphic synthesis constructs: a small but powerful extension to the
language of syntactic templates, which makes it possible to define a program
space in a concise and highly reusable manner, while at the same time retains
the scalability benefits of conventional templates. This approach enables
end-users to reuse predefined templates from a library for a wide variety of
problems with little effort. The paper also describes a novel optimization that
further improves the performance and scalability of the system. We evaluated
the approach on a set of benchmarks that most notably includes desugaring
functions for lambda calculus, which force the synthesizer to discover Church
encodings for pairs and boolean operations
Coherent states for compact Lie groups and their large-N limits
The first two parts of this article surveys results related to the
heat-kernel coherent states for a compact Lie group K. I begin by reviewing the
definition of the coherent states, their resolution of the identity, and the
associated Segal-Bargmann transform. I then describe related results including
connections to geometric quantization and (1+1)-dimensional Yang--Mills theory,
the associated coherent states on spheres, and applications to quantum gravity.
The third part of this article summarizes recent work of mine with Driver and
Kemp on the large-N limit of the Segal--Bargmann transform for the unitary
group U(N). A key result is the identification of the leading-order large-N
behavior of the Laplacian on "trace polynomials."Comment: Submitted to the proceeding of the CIRM conference, "Coherent states
and their applications: A contemporary panorama.
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