Designs for an adaptive tuned vibration absorber with variable shape stiffness element

An adaptive tuned vibration absorber (ATVA) with a smart variable stiffness element is capable of retuning itself in response to a time-varying excitation frequency., enabling effective vibration control over a range of frequencies. This paper discusses novel methods of achieving variable stiffness in an ATVA by changing shape, as inspired by biological paradigms. It is shown that considerable variation in the tuned frequency can be achieved by actuating a shape change, provided that this is within the limits of the actuator. A feasible design for such an ATVA is one in which the device offers low resistance to the required shape change actuation while not being restricted to low values of the effective stiffness of the vibration absorber. Three such original designs are identified: (i) A pinned-pinned arch beam with fixed profile of slight curvature and variable preload through an adjustable natural curvature; (ii) a vibration absorber with a stiffness element formed from parallel curved beams of adjustable curvature vibrating longitudinally; (iii) a vibration absorber with a variable geometry linkage as stiffness element. The experimental results from demonstrators based on two of these designs show good correlation with the theory.

Protocol for the PINCER trial: a cluster randomised trial comparing the effectiveness of a pharmacist-led IT-based intervention with simple feedback in reducing rates of clinically important errors in medicines management in general practices

Background: Medication errors are an important cause of morbidity and mortality in primary care. The aims of this study are to determine the effectiveness, cost effectiveness and acceptability of a pharmacist-led information-technology-based complex intervention compared with simple feedback in reducing proportions of patients at risk from potentially hazardous prescribing and medicines management in general (family) practice. Methods: Research subject group: "At-risk" patients registered with computerised general practices in two geographical regions in England. Design: Parallel group pragmatic cluster randomised trial. Interventions: Practices will be randomised to either: (i) Computer-generated feedback; or (ii) Pharmacist-led intervention comprising of computer-generated feedback, educational outreach and dedicated support. Primary outcome measures: The proportion of patients in each practice at six and 12 months post intervention: - with a computer-recorded history of peptic ulcer being prescribed non-selective non-steroidal anti-inflammatory drugs - with a computer-recorded diagnosis of asthma being prescribed beta-blockers - aged 75 years and older receiving long-term prescriptions for angiotensin converting enzyme inhibitors or loop diuretics without a recorded assessment of renal function and electrolytes in the preceding 15 months. Secondary outcome measures; These relate to a number of other examples of potentially hazardous prescribing and medicines management. Economic analysis: An economic evaluation will be done of the cost per error avoided, from the perspective of the UK National Health Service (NHS), comparing the pharmacist-led intervention with simple feedback. Qualitative analysis: A qualitative study will be conducted to explore the views and experiences of health care professionals and NHS managers concerning the interventions, and investigate possible reasons why the interventions prove effective, or conversely prove ineffective. Sample size: 34 practices in each of the two treatment arms would provide at least 80% power (two-tailed alpha of 0.05) to demonstrate a 50% reduction in error rates for each of the three primary outcome measures in the pharmacist-led intervention arm compared with a 11% reduction in the simple feedback arm. Discussion: At the time of submission of this article, 72 general practices have been recruited (36 in each arm of the trial) and the interventions have been delivered. Analysis has not yet been undertaken.

The neural basis of maternal responsiveness to infants: an fMRI study

Using fMRI, we examined the neural correlates of maternal responsiveness. Ten healthy mothers viewed alternating blocks of video: (i) 40 s of their own infant; (ii) 20 s of a neutral video; (iii) 40 s of an unknown infant and (iv) 20 s of neutral video, repeated 4 times. Predominant BOLD signal change to the contrast of infants minus neutral stimulus occurred in bilateral visual processing regions BA minus neutral stimulus occurred in bilateral visual processing regions (BA 38), left amygdala and visual cortex (BA 19), and to the unknown infant minus own infant contrast in bilateral orbitofrontal cortex (BA 10,47) and medial prefrontal cortex (BA 8). These findings suggest that amygdala and temporal pole may be key sites in mediating a mother's response to her infant and reaffirms their importance in face emotion processing and social behaviour.

Separating hoarding from OCD

There is confusion about the status of excessive hoarding. In particular, there is an unresolved question about whether or not it is a manifestation of obsessive-compulsive disorder (OCD). There are some definite similarities between 'compulsive' hoarding and OCD, but they are outweighed by the differences between them. It is proposed that the matter can be clarified by separating hoarding from OCD, and that this would advance clinical work and research. (c) 2009 Elsevier Ltd. All rights reserved.

Neural response to emotional prosody in schizophrenia and in bipolar affective disorder

Background Evidence suggests a reversal of the normal left-lateralised response to speech in schizophrenia. Aims To test the brain's response to emotional prosody in schizophrenia and bipolar disorder. Method BOLD contrast functional magnetic resonance imaging of subjects while they passively listened or attended to sentences that differed in emotional prosody Results Patients with schizophrenia exhibited normal right-lateralisation of the passive response to 'pure' emotional prosody and relative left-lateralisation of the response to unfiltered emotional prosody When attending to emotional prosody, patients with schizophrenia activated the left insula more than healthy controls. When listening passively, patients with bipolar disorder demonstrated less activation of the bilateral superior temporal gyri in response to pure emotional prosody, and greater activation of the left superior temporal gyrus in response to unfiltered emotional prosody In both passive experiments, the patient groups activated different lateral temporal lobe regions. Conclusions Patients with schizophrenia and bipolar disorder may display some left-lateralisation of the normal right-lateralised temporal lobe response to emotional prosody. Declaration of interest R.M. received a studentship from Neuraxis,, and funding from the Neuroscience and Psychiatry Unit, University of Manchester.

The neural response to emotional prosody, as revealed by functional magnetic resonance imaging

Prosody is an important feature of language, comprising intonation, loudness, and tempo. Emotional prosodic processing forms an integral part of our social interactions. The main aim of this study was to use bold contrast fMRI to clarify the normal functional neuroanatomy of emotional prosody, in passive and active contexts. Subjects performed six separate scanning studies, within which two different conditions were contrasted: (1) "pure" emotional prosody versus rest; (2) congruent emotional prosody versus 'neutral' sentences; (3) congruent emotional prosody versus rest; (4) incongruent emotional prosody versus rest; (5) congruent versus incongruent emotional prosody; and (6) an active experiment in which subjects were instructed to either attend to the emotion conveyed by semantic content or that conveyed by tone of voice. Data resulting from these contrasts were analysed using SPM99. Passive listening to emotional prosody consistently activated the lateral temporal lobe (superior and/or middle temporal gyri). This temporal lobe response was relatively right-lateralised with or without semantic information. Both the separate and direct comparisons of congruent and incongruent emotional prosody revealed that subjects used fewer brain regions to process incongruent emotional prosody than congruent. The neural response to attention to semantics, was left lateralised, and recruited an extensive network not activated by attention to emotional prosody. Attention to emotional prosody modulated the response to speech, and induced right-lateralised activity, including the middle temporal gyrus. In confirming the results of lesion and neuropsychological studies, the current study emphasises the importance of the right hemisphere in the processing of emotional prosody, specifically the lateral temporal lobes. (C) 2003 Elsevier Science Ltd. All rights reserved.

Input and output modality effects in immediate serial recall

In immediate recall tasks, visual recency is substantially enhanced when output interference is low (Cowan, Saults, Elliott, & Moreno, 2002; Craik, 1969) whereas auditory recency remains high even under conditions of high output interference. Ibis auditory advantage has been interpreted in terms of auditory resistance to output interference (e.g., Neath & Surprenant, 2003). In this study the auditory-visual difference at low output interference re-emerged when ceiling effects were accounted for, but only with spoken output. With written responding the auditory advantage remained significantly larger with high than with low output interference. These new data suggest that both superior auditory encoding and modality-specific output interference contribute to the classic auditory-visual modality effect.

The effects of a pre-movement delay on the kinematics of prehension in middle childhood

The present study examined the effects of a pre-movement delay on the kinematics of prehension in middle childhood. Twenty-five children between the ages of 5 and 11 years made visually open-loop reaches to two different sized objects at two different distances along the midline. Reaches took place either (i) immediately, or (ii) 2 s after the occlusion of the stimulus. In all age groups, reaches following the pre-movement delay were characterised by longer movement durations, lower peak velocities, larger peak grip apertures and longer time spent in the final slow phase of the movement. This pattern of results suggests that the representations that control the transport and grasp component are affected similarly by delay, and is consistent with the results previously reported for adults. Such representations therefore appear to develop before the age of 5. (C) 2004 Elsevier B.V. All rights reserved.

Contribution of the double layer to transient faradaic processes: implications for hydrodynamic modulated voltammetry of nanostructures

The electrochemistry of Pt nanostructured electrodes is investigated using hydrodynamic modulated voltammetry (HMV). Here a liquid crystal templating process is used to produce platinum-modified electrodes with a range of surface areas (roughness factor 42.4-280.8). The electroreduction of molecular oxygen at these nanostructured platinum surfaces is used to demonstrate the ability of HMV to discriminate between faradaic and nonfaradaic electrode reactions. The HMV approach shows that the reduction of molecular oxygen experiences considerable signal loss within the high pseudocapacitive region of the voltammetry. Evidence for the contribution of the double layer to transient mass transfer events is presented. In addition, a model circuit and appropriate theoretical analysis are used to illustrate the transient responses of a time variant faradaic component. This in conjunction with the experimental evidence shows that, far from being a passive component in this system, the double layer can contribute to HMV faradaic reactions under certain conditions.