752 resultados para movement skill
Resumo:
Advances in seasonal forecasting have brought widespread socio-economic benefits. However, seasonal forecast skill in the extratropics is relatively modest, prompting the seasonal forecasting community to search for additional sources of predictability. For over a decade it has been suggested that knowledge of the state of the stratosphere can act as a source of enhanced seasonal predictability; long-lived circulation anomalies in the lower stratosphere that follow stratospheric sudden warmings are associated with circulation anomalies in the troposphere that can last up to two months. Here, we show by performing retrospective ensemble model forecasts that such enhanced predictability can be realized in a dynamical seasonal forecast system with a good representation of the stratosphere. When initialized at the onset date of stratospheric sudden warmings, the model forecasts faithfully reproduce the observed mean tropospheric conditions in the months following the stratospheric sudden warmings. Compared with an equivalent set of forecasts that are not initialized during stratospheric sudden warmings, we document enhanced forecast skill for atmospheric circulation patterns, surface temperatures over northern Russia and eastern Canada and North Atlantic precipitation. We suggest that seasonal forecast systems initialized during stratospheric sudden warmings are likely to yield significantly greater forecast skill in some regions.
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Consistent with a negativity bias account, neuroscientific and behavioral evidence demonstrates modulation of even early sensory processes by unpleasant, potentially threat-relevant information. The aim of this research is to assess the extent to which pleasant and unpleasant visual stimuli presented extrafoveally capture attention and impact eye movement control. We report an experiment examining deviations in saccade metrics in the presence of emotional image distractors that are close to a nonemotional target. We additionally manipulate the saccade latency to test when the emotional distractor has its biggest impact on oculomotor control. The results demonstrate that saccade landing position was pulled toward unpleasant distractors, and that this pull was due to the quick saccade responses. Overall, these findings support a negativity bias account of early attentional control and call for the need to consider the time course of motivated attention when affect is implicit
Resumo:
This paper evaluates the extent to which the performance of English Premier League football club managers can be attributed to skill or luck when measured separately from the characteristics of the team. We first use a specification that models managerial skill as a fixed effect and we examine the relationship between the number of points earned in league matches and the club’s wage bill, transfer spending, and the extent to which they were hit by absent players through injuries, suspensions or unavailability. We next implement a bootstrapping approach to generate a simulated distribution of average points that could have taken place after the impact of the manager has been removed. The findings suggest that there are a considerable number of highly skilled managers but also several who perform below expectations. The paper proceeds to illustrate how the approach adopted could be used to determine the optimal time for a club to part company with its manager. We are able to identify in advance several managers who the analysis suggests could have been fired earlier and others whose sackings were hard to justify based on their performances.
Resumo:
It is becoming increasingly important to be able to verify the spatial accuracy of precipitation forecasts, especially with the advent of high-resolution numerical weather prediction (NWP) models. In this article, the fractions skill score (FSS) approach has been used to perform a scale-selective evaluation of precipitation forecasts during 2003 from the Met Office mesoscale model (12 km grid length). The investigation shows how skill varies with spatial scale, the scales over which the data assimilation (DA) adds most skill, and how the loss of that skill is dependent on both the spatial scale and the rainfall coverage being examined. Although these results come from a specific model, they demonstrate how this verification approach can provide a quantitative assessment of the spatial behaviour of new finer-resolution models and DA techniques.
Resumo:
Hamburg atmospheric general circulation model ECHAM3 at T106 resolution (1.125' lat.Aon.) has considerable skill in reproducing the observed seasonal reversal of mean sea level pressure, the location of the summer heat low as well as the position of the monsoon trough over the Indian subcontinent. The present-day climate and its seasonal cycle are realistically simulated by the model over this region. The model simulates the structure, intensity, frequency, movement and lifetime of monsoon depressions remarkably well. The number of monsoon depressions/storms simulated by the model in a year ranged from 5 to 12 with an average frequency of 8.4 yr-', not significantly different from the observed climatology. The model also simulates the interannual variability in the formation of depressions over the north Bay of Bengal during the summer monsoon season. In the warmer atmosphere under doubled CO2 conditions, the number of monsoon depressions/cyclonic storms forming in Indian seas in a year ranged from 5 to 11 with an average frequency of 7.6 yr-', not significantly different from those inferred in the control run of the model. However, under doubled CO2 conditions, fewer depressions formed in the month of June. Neither the lowest central pressure nor the maximum wind speed changes appreciably in monsoon depressions identified under simulated enhanced greenhouse conditions. The analysis suggests there will be no significant changes in the number and intensity of monsoon depressions in a warmer atmosphere.
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One of the key processes that drives rhizosphere microbial activity is the exudation of soluble organic carbon (C) by plant roots. We describe an experiment designed to determine the impact of defoliation on the partitioning and movement of C in grass (Lolium perenne L.), soil and grass-sterile sand microcosms, using a (13)CO(2) pulse-labelling method. The pulse-derived (13)C in the shoots declined over time, but that of the roots remained stable throughout the experiment. There were peaks in the atom% (13)C of rhizosphere CO(2) in the first few hours after labelling probably due to root respiration, and again at around 100 h. The second peak was only seen in the soil microcosms and not in those with sterilised sand as the growth medium, indicating possible microbial activity. Incorporation of the (13)C label into the microbial biomass increased at 100 h when incorporation into replicating cells, as indicated by the amounts of the label in the microbial DNA, started to increase. These results indicate that the rhizosphere environment is conducive to bacterial growth and replication. The results also show that defoliation had no impact on the pattern of movement of (13)C from plant roots into the microbial population in the rhizosphere.
Resumo:
THE clinical skills of medical professionals rely strongly on the sense of touch, combined with anatomical and diagnostic knowledge. Haptic exploratory procedures allow the expert to detect anomalies via gross and fine palpation, squeezing, and contour following. Haptic feedback is also key to medical interventions, for example when an anaesthetist inserts an epidural needle, a surgeon makes an incision, a dental surgeon drills into a carious lesion, or a veterinarian sutures a wound. Yet, current trends in medical technology and training methods involve less haptic feedback to clinicians and trainees. For example, minimally invasive surgery removes the direct contact between the patient and clinician that gives rise to natural haptic feedback, and furthermore introduces scaling and rotational transforms that confuse the relationship between movements of the hand and the surgical site. Similarly, it is thought that computer-based medical simulation and training systems require high-resolution and realistic haptic feedback to the trainee for significant training transfer to occur. The science and technology of haptics thus has great potential to affect the performance of medical procedures and learning of clinical skills. This special section is about understanding
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The role of state and trait anxiety on observer ratings of social skill and negatively biased self-perception of social skill was examined. Participants were aged between 7 and 13 years (mean=9.65; sd=1.77; N=102), 47 had a current anxiety diagnosis and 55 were non-anxious controls. Participants were randomly allocated to a high or low anxiety condition and asked to complete social tasks. Task instructions were adjusted across conditions to manipulate participants’ state anxiety. Observers rated anxious participants as having poorer social skills than non-anxious controls but there was no evidence that anxious participants exhibited a negative self-perception bias, relative to controls. However, as participants’ ratings of state anxiety increased, their perception of their performance became more negatively biased. The results suggest that anxious children may exhibit real impairments in social skill and that high levels of state anxiety can lead to biased judgements of social skills in anxious and non-anxious children.
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A Guide to Office Clerical Time Standards is an instructional performance piece based on a corporate manual from 1960. The pamphlet is focused on the time necessary for the accomplishment of minute labour procedures in the office, from the depressing and releasing of typewriter keys to the opening and closing of filing cabinet drawers. In the performance, seven costumed performers represent the different levels of management and employment while performing the actions described in the guide, accompanied by a live musical score. There has been much discussion of the changes to work in the west following the decline of post-Fordist service sector jobs. These increasingly emphasise the specificity of employees’ knowledge and cognitive skill. However, this greater flexibility and creativity at work has been accompanied by an opposite trajectory. The proletarisation of white collar work has given rise to more bureaucracy, target assessment and control for workers in previously looser creative professions, from academia to the arts. The midcentury office is the meeting point of these cultures, where the assembly line efficiency management of the factory meets the quantifying control of the knowledge economy. A Guide to Office Clerical Time Standards explores the survival of one regime into its successor following the lines of combined and uneven development that have turned the emancipatory promise of immaterial labour into the perma-temp hell of the cognitariat. The movement is accompanied by a score of guitar, bass and drums, the componenets of the rock ‘n’ roll music that rose from the car factories of the motor city and the cotton fields of the southern states to represent the same junction of expression and control.
Resumo:
It has been suggested that the evidence used to support a decision to move our eyes and the confidence we have in that decision are derived from a common source. Alternatively, confidence may be based on further post-decisional processes. In three experiments we examined this. In Experiment 1, participants chose between two targets on the basis of varying levels of evidence (i.e., the direction of motion coherence in a Random-Dot-Kinematogram). They indicated this choice by making a saccade to one of two targets and then indicated their confidence. Saccade trajectory deviation was taken as a measure of the inhibition of the non-selected target. We found that as evidence increased so did confidence and deviations of saccade trajectory away from the non-selected target. However, a correlational analysis suggested they were not related. In Experiment 2 an option to opt-out of the choice was offered on some trials if choice proved too difficult. In this way we isolated trials on which confidence in target selection was high (i.e., when the option to opt-out was available but not taken). Again saccade trajectory deviations were found not to differ in relation to confidence. In Experiment 3 we directly manipulated confidence, such that participants had high or low task confidence. They showed no differences in saccade trajectory deviations. These results support post-decisional accounts of confidence: evidence supporting the decision to move the eyes is reflected in saccade control, but the confidence that we have in that choice is subject to further post-decisional processes.
Resumo:
Grassroots innovations emerge as networks generating innovative solutions for climate change adaptation and mitigation. However, it is unclear if grassroots innovations can be successful in responding to climate change. Little evidence exists on replication, international comparisons are rare, and research tends to overlook discontinued responses in favour of successful ones. We take the Transition Movement as a case study of a rapidly spreading transnational grassroots network, and include both active and non-active local transition initiatives. We investigate the replication of grassroots innovations in different contexts with the aim to uncover general patterns of success and failure, and identify questions for future research. An online survey was carried out in 23 countries (N=276). The data analysis entailed testing the effect of internal and contextual factors of success as drawn from the existing literature, and the identification of clusters of transition initiatives with similar internal and contextual factor configurations. Most transition initiatives consider themselves successful. Success is defined along the lines of social connectivity and empowerment, and external environmental impact. We find that less successful transition initiatives might underestimate the importance of contextual factors and material resources in influencing success. We also find that their diffusion is linked to the combination of local-global learning processes, and that there is an incubation period during which a transition initiative is consolidated. Transition initiatives seem capable of generalising organisational principles derived from unique local experiences that seem to be effective in other local contexts. However, the geographical locations matter with regard to where transition initiatives take root and the extent of their success, and ‘place attachment’ may have a role in the diffusion of successful initatives. We suggest that longitudinal comparative studies can advance our understanding in this regard, as well as inform the changing nature of the definition of success at different stages of grassroots innovation development, and the dynamic nature of local and global linkages.