968 resultados para memory development
Resumo:
The availability of a very accurate dependence graph for a scalar code is the basis for the automatic generation of an efficient parallel implementation. The strategy for this task which is encapsulated in a comprehensive data partitioning code generation algorithm is described. This algorithm involves the data partition, calculation of assignment ranges for partitioned arrays, addition of a comprehensive set of execution control masks, altering loop limits, addition and optimisation of communications for all data. In this context, the development and implementation of strategies to merge communications wherever possible has proved an important feature in producing efficient parallel implementations for numerical mesh based codes. The code generation strategies described here are embedded within the Computer Aided Parallelisation tools (CAPTools) software as a key part of a toolkit for automating as much as possible of the parallelisation process for mesh based numerical codes. The algorithms used enables parallelisation of real computational mechanics codes with only minor user interaction and without any prior manual customisation of the serial code to suit the parallelisation tool.
Resumo:
There can be wide variation in the level of oral/aural language ability that prelingually hearing-impaired children develop after cochlear implantation. Automatic perceptual processing mechanisms have come under increasing scrutiny in attempts to explain this variation. Using mismatch negativity methods, this study explored associations between auditory sensory memory mechanisms and verbal working memory function in children with cochlear implants and a group of hearing controls of similar age. Whilst clear relationships were observed in the hearing children between mismatch activation and working memory measures, this association appeared to be disrupted in the implant children. These findings would fit with the proposal that early auditory deprivation and a degraded auditory signal can cause changes in the processes underpinning the development of oral/aural language skills in prelingually hearing-impaired children with cochlear implants and thus alter their developmental trajectory
Resumo:
Williams syndrome is a genetic disorder that, it has been claimed, results in an unusual pattern of linguistic strengths and weaknesses. The current study investigated the hypothesis that there is a reduced influence of lexical knowledge on phonological short-term memory in Williams syndrome. Fourteen children with Williams syndrome and 2 vocabulary la matched control groups, 20 typically developing children and 13 children with learning difficulties, were tested on 2 probed serial-recall tasks. On the basis of previous findings, it was predicted that children with Williams syndrome would demonstrate (a) a reduced effect of lexicality on the recall of list items, (b) relatively poorer recall of list items compared with recall of serial order, and (c) a reduced tendency to produce lexicalization errors in the recall of nonwords. in fact, none of these predictions were supported. Alternative explanations for previous findings and implications for accounts of language development in Williams syndrome are discussed.
Resumo:
One of the enduring illusions about Northern Ireland is that its society can be conceptualized through a binary distinction between protestant and catholic. unionist and nationalist. It is increasingly apparent that these broad domains are themselves fractured and diverse and that otherness is often conceived from within rather than without. Northern Ireland can also be viewed as a laboratory for identity formation as unionists and loyalists strive to reconcile themselves with the fundamental political changes that have followed in the wake of the Peace Process. This paper considers one aspect of the contestation of belonging that increasingly characterizes unionism. It examines the competition for the ownership of the mythology of the Battle of the Somme ( 1916), long a key event in the unionist narrative. In particular, the paper addresses the ways in which paramilitary organizations are using the Somme to legitimate their own activities but also to distance the loyalist working classes from the former hegemonic Britishness of official unionism and the sectarianism of the Orange Order. The analysis concludes that loyalist identity is being conceptualized thorough a narrative of betrayal from within and at an intensely localized scale.
Resumo:
Drawing on the theoretical insights of Paul Ricoeur this paper investigates the geographies of public remembrance in a post-conflict society. In Northern Ireland, where political divisions have found expression through acts of extreme violence over the past 30 years, questions of memory and an amnesty for forgetting have particular resonance both at the individual and societal level, and render Ricoeur’s framework particularly prescient. Since the signing of the Belfast Agreement in 1998, initiating the Peace Process through consociational structures, discovering a nomenclature and set of practices which would aid in the rapprochement of a deeply divided society has presented a complex array of issues. In this paper I examine the various practices of public remembrance of the 1998 bombing of Omagh as a means of understanding how memory-spaces evolve in a post-conflict context. In Omagh there were a variety of commemorative practices instituted and each, in turn, adopted a different contour towards achieving reconciliation with the violence and grief of the bombing. In particular the Garden of Light project is analysed as a collective monument which, with light as its metaphysical centre, invited the populace to reflect backward on the pain of the bombing while at the same time enabling the society to look forward toward a peaceful future where a politics of hope might eclipse a politics of despair.
Resumo:
Shape Memory Alloy (SMA) actuators, which have the ability to return to a predetermined shape when heated, have many potential applications such as aeronautics, surgical tools, robotics and so on. Although the conventional PID controller can be used with slow response systems, there has been limited success in precise motion control of SMA actuators, since the systems are disturbed by unknown factors beside their inherent nonlinear hysteresis and changes in the surrounding environment of the systems. This paper presents a new development of a SMA position control system by using a self-tuning fuzzy PID controller. This control algorithm is used by tuning the parameters of the PID controller thereby integrating fuzzy inference and producing a fuzzy adaptive PID controller, which can then be used to improve the control performance of nonlinear systems. The experimental results of position control of SMA actuators using conventional and self-tuning fuzzy PID controllers are both included in this paper.
Resumo:
Much recent literature in cultural, political and social geography has considered the relationship between identity, memory, and the urban landscape. This paper interrogates such literature through exploring the complex materialisation of memorialisation in post-Soviet Russia. Using the example of the statue of General Alexei Ermolov in Stavropol', an analysis of the cityscape reveals interethnic tensions over differing interpretations of the life and history of the person upon whom the statue is based. The existence of a rich literature on Ermolov and the Russian colonial experience in the North Caucasus helps to explain this. The symbolic cityscape of Stavropol' plays an important role in interethnic relations in the multi-ethnic city; it is both an arena through which Russian identity is communicated with people and produced and reproduced, and an arena through which Russian citizens compete with each other for authority on historical narratives that operate at and between a number of scales. People's readings of the cityscape can reveal much about power and space in contemporary Russia.
Resumo:
Oligomers of beta-amyloid (Aß) are implicated in the early memory impairment seen in Alzheimer's disease before to the onset of discernable neurodegeneration. Here, the capacity of a novel orally bioavailable, central nervous system-penetrating small molecule 5-aryloxypyrimidine, SEN1500, to prevent cell-derived (7PA2 [conditioned medium] CM) Aß-induced deficits in synaptic plasticity and learned behavior was assessed. Biochemically, SEN1500 bound to Aß monomer and oligomers, produced a reduction in thioflavin-T fluorescence, and protected a neuronal cell line and primary cortical neurons exposed to synthetic soluble oligomeric Aß1-42. Electrophysiologically, SEN1500 alleviated the in vitro depression of long-term potentiation induced by both synthetic Aß1-42 and 7PA2 CM, and alleviated the in vivo depression of long-term potentiation induced by 7PA2 CM, after systemic administration. Behaviorally, oral administration of SEN1500 significantly reduced memory-related deficits in operant responding induced after intracerebroventricular injection of 7PA2 CM. SEN1500 reduced cytotoxicity, acute synaptotoxicity, and behavioral deterioration after in vitro and in vivo exposure to synthetic Aß and 7PA2 CM, and shows promise for development as a clinically viable disease-modifying Alzheimer's disease treatment. © 2013 Elsevier Inc.
Resumo:
Cross-sectional and longitudinal data consistently indicate that mathematical difficulties are more prevalent in older than in younger children (e.g. Department of Education, 2011). Children’s trajectories can take a variety of shapes such as linear, flat, curvilinear and uneven, and shape has been found to vary within children and across tasks (J Jordan et al. 2009). There has been an increase in the use of statistical methods which are specifically designed to study development, and this has greatly improved our understanding of children’s mathematical development. However, the effects of many cognitive and social variables (e.g. working memory and verbal ability) on mathematical development are unclear. It is likely that greater consistency between studies will be achieved by adopting a componential approach to study mathematics, rather than treating mathematics as a unitary concept.
Resumo:
We examined the relationship between cognitive capacity and heuristic responding on four types of reasoning and decision-making tasks. A total of 84 children, between 5 years 2 months and 11 years 7 months of age, participated in the study. There was a marked increase in heuristic responding with age that was related to increases in cognitive capacity. These findings are inconsistent with the predominant dual-process accounts of reasoning and decision making as applied to development. We offer an alternative explanation of the findings, considering them in the context of recent claims concerning the role of working memory in contextualized reasoning.
Resumo:
Children born very preterm, even when intelligence is broadly normal, often experience selective difficulties in executive function and visual-spatial processing. Development of structural cortical connectivity is known to be altered in this group, and functional magnetic resonance imaging (fMRI) evidence indicates that very preterm children recruit different patterns of functional connectivity between cortical regions during cognition. Synchronization of neural oscillations across brain areas has been proposed as a mechanism for dynamically assigning functional coupling to support perceptual and cognitive processing, but little is known about what role oscillatory synchronization may play in the altered neurocognitive development of very preterm children. To investigate this, we recorded magnetoencephalographic (MEG) activity while 7-8 year old children born very preterm and age-matched full-term controls performed a visual short-term memory task. Very preterm children exhibited reduced long-range synchronization in the alpha-band during visual short-term memory retention, indicating that cortical alpha rhythms may play a critical role in altered patterns functional connectivity expressed by this population during cognitive and perceptual processing. Long-range alpha-band synchronization was also correlated with task performance and visual-perceptual ability within the very preterm group, indicating that altered alpha oscillatory mechanisms mediating transient functional integration between cortical regions may be relevant to selective problems in neurocognitive development in this vulnerable population at school age.