The utility of aminoterminal pro-B-type natriuretic peptide for the detection of preclinical systolic and diastolic dysfunction in the community

Background: There is scant data regarding methods to identify subjects in the community with preclinical left ventricular (LV) systolic and diastolic dysfunction. Methods: A population-based sample of 1229 older adults underwent examination with transthoracic echocardiography and measurement of circulating aminoterminal pro-Btype natriuretic peptide (N-BNP) levels. Heart failure status was ascertained according to past history and clinical examination. The ability of N-BNP to detect preclinical LV ejection fraction (EF)

AVALIAÇÃO DA ACEITAÇÃO DO PORTAL INOVAÇÃO: UM ESTUDO DE CASO

Esta pesquisa apresenta estudo de caso cujo objetivo foi analisar a aceitação do Portal Inovação, identificando os fatores preditivos da intenção comportamental de uso e do comportamento de uso direcionadores da adoção da tecnologia por seus usuários via extensão do Modelo Unificado de Aceitação de Tecnologia, denominado pela sigla UTAUT (Unified Theory of Acceptance and Use of Technololgy) de Venkatesh et al. (2003). O objeto da pesquisa o Portal Inovação foi desenvolvido pelo Ministério da Ciência, Tecnologia e Inovação (MCTI) em parceria com o Centro de Gestão e Estudos Estratégicos (CGEE), Associação Brasileira de Desenvolvimento Industrial (ABDI) e Instituto Stela, visando atender às demandas do Sistema Nacional de Ciência, Tecnologia e Inovação (SNCTI) do País. Para atingir os objetivos propostos, recorreu-se às abordagens qualitativa, que foi subsidiada pelo método estudo de caso (YIN, 2005) e quantitativa, apoiada pela metodologia UTAUT, aplicada a usuários do portal e que contemplou o resultado de 264 respondentes validados. Quanto ao material de análise, utilizou-se da pesquisa bibliográfica sobre governo eletrônico (e-Gov), Internet, Sistema Nacional de Inovação, modelos de aceitação de tecnologia, dados oficiais públicos e legislações atinentes ao setor de inovação tecnológica. A técnica de análise empregada quantitativamente consistiu no uso de modelagem por equações estruturais, com base no algoritmo PLS (Partial Least Square) com bootstrap de 1.000 reamostragens. Os principais resultados obtidos demonstraram alta magnitude e significância preditiva sobre a Intenção Comportamental de Uso do Portal pelos fatores: Expectativa de Desempenho e Influência Social. Além de evidenciarem que as condições facilitadoras impactam significativamente sobre o Comportamento de Uso dos usuários. A conclusão principal do presente estudo é a de que ao considerarmos a aceitação de um portal governamental em que a adoção é voluntária, o fator social é altamente influente na intenção de uso da tecnologia, bem como os aspectos relacionados à produtividade consequente do usuário e o senso de utilidade; além da facilidade de interação e domínio da ferramenta. Tais constatações ensejam em novas perspectivas de pesquisa e estudos no âmbito das ações de e-Gov, bem como no direcionamento adequado do planejamento, monitoramento e avaliação de projetos governamentais.

Methods and trends of performance benchmarking in UK utility regulation

Regulation is subject to information asymmetries that can lead to allocative and productive inefficiencies. One solution, suggested by Shleifer in 1985 and now adopted by many regulatory bodies round the world, is 'benchmarking', which is sometimes called 'yardstick competition'. In this paper we consider Shleifer's original approach to benchmarking and contrast this with the actual use of benchmarking by UK regulatory bodies in telecommunications, water and the energy sector since the privatizations of the 1980s and early 1990s. We find that benchmarking plays only one part and sometimes a small part in the setting of regulatory price caps in the UK. We also find that in practice benchmarking has been subject to a number of difficulties, which mean that it is never likely to be more than one tool in the regulator's armoury. The UK's experience provides lessons for regulation internationally. © 2006 Elsevier Ltd. All rights reserved.

Attentional shifts towards an expected visual target alter the level of alpha-band oscillatory activity in the human calcarine cortex

Neuronal operations associated with the top-down control process of shifting attention from one locus to another involve a network of cortical regions, and their influence is deemed fundamental to visual perception. However, the extent and nature of these operations within primary visual areas are unknown. In this paper, we used magnetoencephalography (MEG) in combination with magnetic resonance imaging (MRI) to determine whether, prior to the onset of a visual stimulus, neuronal activity within early visual cortex is affected by covert attentional shifts. Time/frequency analyses were used to identify the nature of this activity. Our results show that shifting attention towards an expected visual target results in a late-onset (600 ms postcue onset) depression of alpha activity which persists until the appearance of the target. Independent component analysis (ICA) and dipolar source modeling confirmed that the neuronal changes we observed originated from within the calcarine cortex. Our results further show that the amplitude changes in alpha activity were induced not evoked (i.e., not phase-locked to the cued attentional task). We argue that the decrease in alpha prior to the onset of the target may serve to prime the early visual cortex for incoming sensory information. We conclude that attentional shifts affect activity within the human calcarine cortex by altering the amplitude of spontaneous alpha rhythms and that subsequent modulation of visual input with attentional engagement follows as a consequence of these localized changes in oscillatory activity. © 2005 Elsevier B.V. All rights reserved.

Control, accounting and value-for-money implications of utility regulation:a literature review

This paper reviews and evaluates the literature concerning the privatisation and regulation of the utility industries in the UK. The economic theories behind and political reasons for the programme are considered to give the reader an appreciation of the environment from which these organisations were born and the implications for their continued existence. Once this has been established the paper then considers the role that accounting has played and will continue to play in these industries. This includes consideration of the technical questions which these new organisations are asking and also the role that accounting has in the organisational structure and culture. It draws as a conclusion that these recently privatised industries provide a unique and rich source for further accounting research.

Ability assessment and job structure measures in occupational mobility

Recent and potential changes in technology have resulted in the anticipation of increases in the frequency of job changes. This has led manpower policy makers to investigate the feasibility of incorporating the employment skills of job groups in the general prediction of future job learning and performance with a view to the establishment of "job families" within which transfer might be considered reciprocally high. A structured job analysis instrument (the Position Analysis Questionnaire) is evaluated in terms of two distinct sets of scores; job dimensions and synthetically established attribute/trait profiles. Studies demonstrate that estimates of a job's structure/dimensions and requisite human attributes can be reliably established. Three alternative techniques of statistically assembling profiles of the requisite human attributes for jobs are found to have differential levels of reliability and differential degrees of validity in their estimation of the "actual" ability requirements of jobs. The utility of these two sets of job descriptors to serve as representations of the cognitive structure similarity of job groups is investigated in a study which simulates a job transfer situation. The central role of the index of similarity used to assess the relationship between "target" and "present" job is demonstrated. The relative extents to which job structure similarity and job attribute similariity are associated with positive transfer are investigated. The studies demonstrate that the dimensions of jobs, and more fruitfully their requisite human attributes can serve as bases to predict job transfer learning and performance. The nature of the index of similarity used to optimally formulate predictions of transfer is such that networks of jobs might be establishable to which current job incumbents could be expected to transfer positively. The derivation of "job families" with anticipated reciprocal transfer consequences is considered to be less appropriate.

The clinical utility of the middle latency and 40Hz auditory evoked potentials in audiological electrodiagnosis

The two elcctrophysiological tests currently favoured in the clinical measurement of hearing threshold arc the brainstorm evoked potential (BAEP) and the slow vertex response (SVR). However, both tests possess disadvantages. The BAEP is the test of choice in younger patients as it is stable at all levels of arousal, but little information has been obtained to date at a range of frequencies. The SVR is frequency specific but is unreliable in certain adult subjects and is unstable during sleep or in young children. These deficiencies have prompted research into a third group of potentials, the middle latency response (MLR) and the 40HZ responses. This research has compared the SVR and 40HZ response in waking adults and reports that the 40HZ test can provide a viable alternative to the SVR provided that a high degree of subject relaxation is ensured. A second study examined the morphology of the MLR and 40HZ during sleep. This work suggested that these potentials arc markedly different during sleep and that methodological factors have been responsible for masking these changes in previous studies. The clinical possibilities of tone pip BAEPs were then examined as these components were proved to be the only stable responses present in sleep. It was found that threshold estimates to 5OOHz, lOOOHz and 4000Hz stimuli could be made to within 15dBSL in most cases. A final study looked more closely at methods of obtaining frequency specific information in sleeping subjects. Threshold estimates were made using established BAEP parameters and this was compared to a 40HZ procedure which recorded a series of BAEPs over a 100msec. time sweep. Results indicated that the 40mHz procedure was superior to existing techniques in estimating threshold to low frequency stimuli. This research has confirmed a role for the MLR and 40Hz response as alternative measures of hearing capability in waking subjects and proposes that the 40Hz technique is useful in measuring frequency specific thresholds although the responses recorded derive primarily from the brainstem.

The Riesz transform and simultaneous representations of phase, energy and orientation in spatial vision

To represent the local orientation and energy of a 1-D image signal, many models of early visual processing employ bandpass quadrature filters, formed by combining the original signal with its Hilbert transform. However, representations capable of estimating an image signal's 2-D phase have been largely ignored. Here, we consider 2-D phase representations using a method based upon the Riesz transform. For spatial images there exist two Riesz transformed signals and one original signal from which orientation, phase and energy may be represented as a vector in 3-D signal space. We show that these image properties may be represented by a Singular Value Decomposition (SVD) of the higher-order derivatives of the original and the Riesz transformed signals. We further show that the expected responses of even and odd symmetric filters from the Riesz transform may be represented by a single signal autocorrelation function, which is beneficial in simplifying Bayesian computations for spatial orientation. Importantly, the Riesz transform allows one to weight linearly across orientation using both symmetric and asymmetric filters to account for some perceptual phase distortions observed in image signals - notably one's perception of edge structure within plaid patterns whose component gratings are either equal or unequal in contrast. Finally, exploiting the benefits that arise from the Riesz definition of local energy as a scalar quantity, we demonstrate the utility of Riesz signal representations in estimating the spatial orientation of second-order image signals. We conclude that the Riesz transform may be employed as a general tool for 2-D visual pattern recognition by its virtue of representing phase, orientation and energy as orthogonal signal quantities.