3,111 research outputs found
A Revised Textual Tree Trace Notation for Prolog
This paper describes a ''textual tree trace'' (TTT) notation for representing the execution of Prolog programs. Compact, textual and non-linear, it provides detailed information about variable binding and execution history, and distinguishes several modes of goal failure. The revised form given here, yet to be empirically tested, is partly informed by Paul Mulholland's empirical comparisons of Prolog trace notations, in which an earlier version of the TTT notation was amongst those studied and criticised. The work presented here is an updated version of a previous workshop paper (Taylor, du Boulay, & Patel, 1994)
Short-Interval Cortical Inhibition and Intracortical Facilitation during Submaximal Voluntary Contractions Changes with Fatigue
This study determined whether short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) change during a sustained submaximal isometric contraction. On 2 days, 12 participants (6 men, 6 women) performed brief (7-s) elbow flexor contractions before and after a 10-min fatiguing contraction; all contractions were performed at the level of integrated electromyographic activity (EMG) which produced 25 % maximal unfatigued torque. During the brief 7-s and 10-min submaximal contractions, single (test) and paired (conditioning–test) transcranial magnetic stimuli were applied over the motor cortex (5 s apart) to elicit motor-evoked potentials (MEPs) in biceps brachii. SICI and ICF were elicited on separate days, with a conditioning–test interstimulus interval of 2.5 and 15 ms, respectively. On both days, integrated EMG remained constant while torque fell during the sustained contraction by ~51.5 % from control contractions, perceived effort increased threefold, and MVC declined by 21–22 %. For SICI, the conditioned MEP during control contractions (74.1 ± 2.5 % of unconditioned MEP) increased (less inhibition) during the sustained contraction (last 2.5 min: 86.0 ± 5.1 %; P \u3c 0.05). It remained elevated in recovery contractions at 2 min (82.0 ± 3.8 %; P \u3c 0.05) and returned toward control at 7-min recovery (76.3 ± 3.2 %). ICF during control contractions (conditioned MEP 129.7 ± 4.8 % of unconditioned MEP) decreased (less facilitation) during the sustained contraction (last 2.5 min: 107.6 ± 6.8 %; P \u3c 0.05) and recovered to 122.8 ± 4.3 % during contractions after 2 min of recovery. Both intracortical inhibitory and facilitatory circuits become less excitable with fatigue when assessed during voluntary activity, but their different time courses of recovery suggest different mechanisms for the fatigue-related changes of SICI and ICF
Agendamelding and COVID-19: the dance of horizontal and vertical media in a pandemic
How are attitudes formed in the 21st Century, and who sets the agenda for initial COVID-19 coverage in the United States? We explore these questions using a random sample of 6 million tweets from a population of 224 million tweets collected between January 2020 and June 2020. In conjunction with a content analysis of legacy media such as newspapers, we examine the second-level agendamelding process during the onset of the COVID-19 pandemic in the United States. The findings demonstrate that in the early weeks of the pandemic, public opinion on Twitter about the virus was distinctly different than the coverage of the issue in the traditional media. The attributes used to describe it on social media demonstrate users relying on their past experiences and personal beliefs to talk about the virus. In the 1st week of February, public opinion, traditional media, and social media converged, but traditional media soon becomes the main agenda setter of COVID-19 for 13 weeks. However, for the final 5 weeks of our sample, traditional media are taken over by social media. The findings also show that, except for a few weeks at the onset of the outbreak, Twitter users relied on their personal experiences far less than what statistical models predicted and allowed. Instead, traditional media and social media to shape their opinion of the issue
Collaborative working within UK NHS secondary care and across sectors for COPD and the impact of peer review : qualitative findings from the UK National COPD Resources and Outcomes Project
Introduction: We investigated the effects on collaborative work within the UK National Health Service (NHS) of an intervention for service quality improvement: informal, structured, reciprocated, multidisciplinary peer review with feedback and action plans. The setting was care for chronic obstructive pulmonary disease (COPD).
Theory and methods: We analysed semi-structured interviews with 43 hospital respiratory consultants, nurses and general managers at 24 intervention and 11 control sites, as part of a UK randomised controlled study, the National COPD Resources and Outcomes Project (NCROP), using Scott’s conceptual framework for action (inter-organisational, intra-organisational, inter-professional and inter-individual). Three areas of care targeted by NCROP involved collaboration across primary and secondary care.
Results: Hospital respiratory department collaborations with commissioners and hospital managers varied. Analysis suggested that this is related to team responses to barriers. Clinicians in unsuccessful collaborations told ‘atrocity stories’ of organisational, structural and professional barriers to service improvement. The others removed barriers by working with government and commissioner agendas to ensure continued involvement in patients’ care. Multidisciplinary peer review facilitated collaboration between participants, enabling them to meet, reconcile differences and exchange ideas across boundaries.
Conclusions: The data come from the first randomised controlled trial of organisational peer review, adding to research into UK health service collaborative work, which has had a more restricted focus on inter-professional relations. NCROP peer review may only modestly improve collaboration but these data suggest it might be more effective than top-down exhortations to change when collaboration both across and within organisations is required
Comparison of Contrasting Prolog Trace Output Formats
This paper reports on a comparative study of three Prolog trace packages. 43 students of an introductory Prolog course solved 5 different Prolog programming problems in each of three different conditions (using isomorphic problem variants to disguise recurring tasks). Each of the three conditions provided subjects with static screen-snapshot-mockups derived from one of three different trace packages (''conventional'' Spy; ''graphical AND/OR tree-based'' TPM*; ''informative textual'' EPTB). When tracers explicitly displayed the information asked for in the problem, subjects solved the problems more quickly. Conversely, when trace output obscured the required information (or necessitated difficult detective work to uncover the information), solution times were longer and answers less accurate. Deciding on a ''good'' format for display is thus a task-dependent decision, and impacts directly on the user's cognitive ability to solve a problem
Exacerbating the burden of cardiovascular disease:how can we address cardiopulmonary risk in individuals with chronic obstructive pulmonary disease?
Bayesian inference of a new Mallows model for characterising symptom sequences applied in primary progressive aphasia
Machine learning models offer the potential to understand diverse datasets in
a data-driven way, powering insights into individual disease experiences and
ensuring equitable healthcare. In this study, we explore Bayesian inference for
characterising symptom sequences, and the associated modelling challenges. We
adapted the Mallows model to account for partial rankings and right-censored
data, employing custom MCMC fitting. Our evaluation, encompassing synthetic
data and a primary progressive aphasia dataset, highlights the model's efficacy
in revealing mean orderings and estimating ranking variance. This holds the
potential to enhance clinical comprehension of symptom occurrence. However, our
work encounters limitations concerning model scalability and small dataset
sizes.Comment: Extended Abstract presented at Machine Learning for Health (ML4H)
symposium 2023, December 10th, 2023, New Orleans, United States, 8 page
Delocalization of brane gravity by a bulk black hole
We investigate the analogue of the Randall-Sundrum brane-world in the case
when the bulk contains a black hole. Instead of the static vacuum Minkowski
brane of the RS model, we have an Einstein static vacuum brane. We find that
the presence of the bulk black hole has a dramatic effect on the gravity that
is felt by brane observers. In the RS model, the 5D graviton has a stable
localized zero-mode that reproduces 4D gravity on the brane at low energies.
With a bulk black hole, there is no such solution -- gravity is delocalized by
the 5D horizon. However, the brane does support a discrete spectrum of
metastable massive bound states, or quasinormal modes, as was recently shown to
be the case in the RS scenario. These states should dominate the high frequency
component of the bulk gravity wave spectrum on a cosmological brane. We expect
our results to generalize to any bulk spacetime containing a Killing horizon.Comment: 7 pages, 6 figure
Confirmatory factor analysis of the Test of Performance Strategies (TOPS) among adolescent athletes
The aim of the present study was to examine the factorial validity of the Test of Performance Strategies (TOPS; Thomas et al., 1999) among adolescent athletes using confirmatory factor analysis. The TOPS was designed to assess eight psychological strategies used in competition (i.e. activation, automaticity, emotional control, goal-setting, imagery, negative thinking, relaxation and self-talk,) and eight used in practice (the same strategies except negative thinking is replaced by attentional control). National-level athletes (n = 584) completed the 64-item TOPS during training camps. Fit indices provided partial support for the overall measurement model for the competition items (robust comparative fit index = 0.92, Tucker-Lewis index = 0.88, root mean square error of approximation = 0.05) but minimal support for the training items (robust comparative fit index = 0.86, Tucker-Lewis index = 0.81, root mean square error of approximation = 0.06). For the competition items, the automaticity, goal-setting, relaxation and self-talk scales showed good fit, whereas the activation, emotional control, imagery and negative thinking scales did not. For the practice items, the attentional control, emotional control, goal-setting, imagery and self-talk scales showed good fit, whereas the activation, automaticity and relaxation scales did not. Overall, it appears that the factorial validity of the TOPS for use with adolescents is questionable at present and further development is required
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