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The magic of the Last Planner® System for Nigerian construction
Extremely poor economic performance of the Nigerian construction industry suggests that non-value adding activities are prevalent, which result not only in the reduction of contractors’ profit margin but economic loss for the country in general. This study analyses non-value adding activities in Nigerian construction sites. The research seeks to establish potential antidotes within the Last Planner® System (LPS) and reveal the elements of the LPS which could be abstracted into Nigerian construction to improve performance. It was found that these elements form the theoretical basis for developing a lean approach that was labelled Last Planner® thinking
A support vector machine for predicting spontaneous termination of paroxysmal atrial fibrillation episodes
Antisocial Learning: Using Learning Window Width to Model Callous-Unemotional Traits?
Psychopathic traits and the childhood analogue, callous-unemotional traits, have been severely neglected by the research field in terms of mechanistic, falsifiable accounts. This is surprising given that some of the core symptoms of the disorder point towards problems with basic components of associative learning. In this manuscript we describe a new mechanistic account that is concordant with current cognitive theories of psychopathic traits and is also able to replicate previous empirical data. The mechanism we describe is one of individual differences in an index we have called, “learning window width”. Here we show how variation in this index would result in different outcome expectations which, in turn, would lead to differences in behaviour. The proposed mechanism is intuitive and simple with easily calculated behavioural implications. Our hope is that this model will stimulate discussion and the use of mechanistic and computational accounts to improve our understanding in this area of research
Improving uptake of perinatal autopsy
PURPOSE OF REVIEW: Uptake of perinatal autopsy has declined in the West over the past 30 years, largely because of reduced parental acceptance of a traditional invasive autopsy. Several studies have recently investigated the decline to identify the key factors and how they may be mitigated. RECENT FINDINGS: Three main themes were identified that have been found to improve uptake of perinatal autopsy: improved communication, in particular ensuring the consent process was conducted as a conversation with time spent talking through the procedure and allowing time for questions; health professional training to ensure staff discussing autopsy with parents have adequate understanding of the procedure and are able to convey confidence and empathy; and availability of less invasive autopsy, including noninvasive as well as minimally invasive options. These should be offered alongside standard autopsy, which some parents may still prefer. SUMMARY: This review highlights that the discussions that take place, and the options that are available to parents, can profoundly impact whether or not they consent to autopsy investigation. Further research should focus on the impact of offering less invasive options as well as evaluating the training and support materials that have recently been developed
Anxiety promotes memory for mood-congruent faces but does not alter loss aversion
Pathological anxiety is associated with disrupted cognitive processing, including working memory and decision-making. In healthy individuals, experimentally-induced state anxiety or high trait anxiety often results in the deployment of adaptive harm-avoidant behaviours. However, how these processes affect cognition is largely unknown. To investigate this question, we implemented a translational within-subjects anxiety induction, threat of shock, in healthy participants reporting a wide range of trait anxiety scores. Participants completed a gambling task, embedded within an emotional working memory task, with some blocks under unpredictable threat and others safe from shock. Relative to the safe condition, threat of shock improved recall of threat-congruent (fearful) face location, especially in highly trait anxious participants. This suggests that threat boosts working memory for mood-congruent stimuli in vulnerable individuals, mirroring memory biases in clinical anxiety. By contrast, Bayesian analysis indicated that gambling decisions were better explained by models that did not include threat or treat anxiety, suggesting that: (i) higher-level executive functions are robust to these anxiety manipulations; and (ii) decreased risk-taking may be specific to pathological anxiety. These findings provide insight into the complex interactions between trait anxiety, acute state anxiety and cognition, and may help understand the cognitive mechanisms underlying adaptive anxiety
Effect of attention control on sustained attention during induced anxiety
Anxiety has wide-reaching and complex effects on cognitive performance. Although it can intrude on cognition and interfere with performance, it can also facilitate information processing and behavioural responses. In a previous study, we showed that anxiety induced by threat of shock facilitates performance on the Sustained Attention to Response Task, a vigilance test, which probes response inhibition to infrequent nogo stimuli. The present study sought to identify factors that may have contributed to such improved performance, including on- and off-task thinking (assessed with thought probes) and individual differences in attention control, as measured with the Attention Control Scale. Replicating our prior finding, we showed that shock threat significantly reduced errors of commission on the nogo trials. However, we extended this finding in demonstrating that this effect was driven by subjects with low attention control. We therefore confirm that anxiety increases inhibitory control of prepotent responses-a mechanism which is adaptive under threat-and show that this effect is greater in those who rely more upon such prepotent responding, i.e., those with low attentional control
Towards Deconstruction of the Type D (2,0) Theory
We propose a four-dimensional supersymmetric theory that deconstructs, in a
particular limit, the six-dimensional theory of type . This 4d
theory is defined by a necklace quiver with alternating gauge nodes
and . We test this proposal by comparing the
6d half-BPS index to the Higgs branch Hilbert series of the 4d theory. In the
process, we overcome several technical difficulties, such as Hilbert series
calculations for non-complete intersections, and the choice of
versus gauge groups. Consistently, the result matches the Coulomb
branch formula for the mirror theory upon reduction to 3d
A vascular cause of unexplained exertional wheeze : Keeping a high index of suspicion
© 2019 A 31-year-old female was referred with a history of unexplained exertional breathlessness. The patient had normal resting lung function and a CT thorax showed no significant abnormality. Closer scrutiny of the flow-volume loop confirmed an elevated Empey's index. Cardiopulmonary exercise testing with continuous laryngoscopy was conducted to evaluate the upper airway response to exercise which confirmed loud biphasic wheeze. A bronchoscopy revealed no stenosis nor intraluminal narrowing, however, a contrast CT confirmed a right-sided aortic arch and aberrant left subclavian artery. Following multidisciplinary review, the patient opted for a surgical approach to treatment however despite initially reporting an improvement in symptoms and exercise capacity continued to suffer exertional wheeze two-years post-surgery. This clinical report describes a rare vascular cause of exertional wheeze but also provides a cautionary note in terms of providing a guarded prognosis for adults undergoing surgical intervention for tracheal compression arising from congenital vascular abnormalities
When Expectancies Are Violated: A Functional Magnetic Resonance Imaging Study
Positive and negative expectancies drive behavioral and neurobiological placebo and nocebo effects, which in turn can have profound effects on patient improvement or worsening. However, expectations of events and outcomes are often not met in daily life and clinical practice. It is currently unknown how this affects placebo and nocebo effects. We have demonstrated that the violation of expectancies, such as when there is a discrepancy between what is expected and what is actually presented, reduces both placebo and nocebo effects while causing an extinction of placebo effects. The reduction of placebo and nocebo effects was paralleled by an activation of the left inferior parietal cortex, a brain region that redirects attention when discrepancies between sensory and cognitive events occur. Our findings highlight the importance of expectancy violation in shaping placebo and nocebo effects and open up new avenues for managing positive and negative expectations in clinical trials and practices
Matchings on infinite graphs
Elek and Lippner (2010) showed that the convergence of a sequence of
bounded-degree graphs implies the existence of a limit for the proportion of
vertices covered by a maximum matching. We provide a characterization of the
limiting parameter via a local recursion defined directly on the limit of the
graph sequence. Interestingly, the recursion may admit multiple solutions,
implying non-trivial long-range dependencies between the covered vertices. We
overcome this lack of correlation decay by introducing a perturbative parameter
(temperature), which we let progressively go to zero. This allows us to
uniquely identify the correct solution. In the important case where the graph
limit is a unimodular Galton-Watson tree, the recursion simplifies into a
distributional equation that can be solved explicitly, leading to a new
asymptotic formula that considerably extends the well-known one by Karp and
Sipser for Erd\"os-R\'enyi random graphs.Comment: 23 page
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