Sensory hypersensitivity occurs soon after whiplash injury and is associated with poor recovery

Hypersensitivity to a variety of sensory Stimuli is a feature of persistent whiplash associated disorders (WAD). However, little is known about sensory disturbances from the time Of injury until transition to either recovery or symptom persistence. Quantitative sensory testing (pressure and thermal pain thresholds, the brachial plexus provocation test), the sympathetic vasoconstrictor reflex and psychological distress (GHQ-28) were prospectively measured in 76 whiplash Subjects within 1 month of injury and then 2, 3 and 6 months post-injury. Subjects were classified at 6 months post-injury using scores on the Neck Disability Index: recovered (30). Sensory and sympathetic nervous system tests were also measured in 20 control subjects. All whiplash groups demonstrated local mechanical hyperalgesia in the cervica spine at 1 month post-injury. This hyperalgesia persisted in those with moderate/severe symptoms at 6 months but resolved by 2 months in those who had recovered or reported persistent mild symptoms. Only those with persistent moderate/severe symptoms at 6 months demonstrated generalised hypersensitivity to all sensory tests. These changes Occurred within 1 month of injury and remained Unchanged throughout the Study period. Whilst no significant group differences were evident for the sympathetic vasoconstrictor response, the moderate/severe group showed a tendency for diminished sympathetic reactivity. GHQ-28 scores of the moderate/severe group were higher than those of the other two groups. The differences in GHQ-28 did not impact on any of the sensory measures. These findings suggest that those with persistent moderate/severe symptoms at 6 months display, soon after injury, generalised hypersensitivity suggestive of changes in central pain processing mechanisms. This phenomenon did not Occur in those who recover or those with persistent mild symptoms. (C) 2003 International Association for the Study of Pain. Published by Elsevier Science B.V. All rights reserved.

Characterization of acute whiplash-associated disorders

Study Design. An experimental study of motor and sensory function and psychological distress in subjects with acute whiplash injury. Objectives. To characterize acute whiplash injury in terms of motor and sensory systems dysfunction and psychological distress and to compare subjects with higher and lesser levels of pain and disability. Summary of Background Data. Motor system dysfunction, sensory hypersensitivity, and psychological distress are present in chronic whiplash associated disorders ( WAD), but little is known of such factors in the acute stage of injury. As higher levels of pain and disability in acute WAD are accepted as signs of poor outcome, further characterization of this group from those with lesser symptoms is important. Materials and Methods. Motor function ( cervical range of movement [ ROM], joint position error [JPE]; activity of the superficial neck flexors [EMG] during a test of craniocervical flexion), quantitative sensory testing ( pressure, thermal pain thresholds, and responses to the brachial plexus provocation test), and psychological distress (GHQ-28, TAMPA, IES) were measured in 80 whiplash subjects ( WAD II or III) within 1 month of injury, as were 20 control subjects. Results. Three subgroups were identified in the cohort using cluster analysis based on the Neck Disability Index: those with mild, moderate, or severe pain and disability. All whiplash groups demonstrated decreased ROM and increased EMG compared with the controls ( all P < 0.01). Only the moderate and severe groups demonstrated greater JPE and generalized hypersensitivity to all sensory tests ( all P < 0.01). The three whiplash subgroups demonstrated evidence of psychological distress, although this was greater in the moderate and severe groups. Measures of psychological distress did not impact on between group differences in motor or sensory tests. Conclusions. Acute whiplash subjects with higher levels of pain and disability were distinguished by sensory hypersensitivity to a variety of stimuli, suggestive of central nervous system sensitization occurring soon after injury. These responses occurred independently of psychological distress. These findings may be important for the differential diagnosis of acute whiplash injury and could be one reason why those with higher initial pain and disability demonstrate a poorer outcome.

The rapid screen of concussion: An evaluation of the non-word repetition test for use in mTBI research

Primary objectives: (1) To investigate the Nonword Repetition test (NWR) as an index of sub-vocal rehearsal deficits after mild traumatic brain injury (mTBI); (2) to assess the reliability, validity and sensitivity of the NWR; and (3) to compare the NWR to more sensitive tests of verbal memory. Research design: An independent groups design. Methods and procedures: Study 1 administered the NWR to 46 mTBI and 61 uninjured controls with the Rapid Screen of Concussion (RSC). Study 2 compared mTBI, orthopaedic and uninjured participants on the NWR and the Hopkins Verbal Learning Test (HVLT-R). Main outcomes and results: The NWR did not improve the diagnostic accuracy of the RSC. However, it is reliable and indexes sub-vocal rehearsal speed. These findings provide evidence that although the current form of the NWR lacks sensitivity to the impact of mTBI, the development of a more sensitive test of sub-vocal rehearsal deficits following mTBI is warranted.

Using fear appeals to promote cancer screening - are we scaring the wrong people?

There is debate regarding the use of fear appeals (emphasizing severe threats to health) in social marketing, to encourage preventive behaviours, such as screening for breast cancer. While it has been found that fear appeals may result in attitude and behaviour change there is also the risk of inciting inappropriate levels of fear, motivating the wrong audience or instigating maladaptive behaviour in the target group such as denial or defensive avoidance. This study examined the impact of an experimental threat manipulation for mammography screening on a group of women in regional Australia. The study found that varying the level of threat had no impact on stated intentions of the women to undergo mammographic screening. However, it also found that high-threat messages resulted in stronger negative emotional reactions and greater perceived susceptibility among younger women who are not the target group for screening in Australia. The results of this study emphasize the importance of limiting the use of high levels of threat in social marketing campaigns, and ensuring that campaigns are appropriately designed to specifically impact upon and motivate the target group. Copyright © 2006 John Wiley & Sons, Ltd.

Experiments to assess the transport of fibrous insulation debris

Loss of coolant accidents (LOCA) in the primary cooling circuit of a nuclear reactor may result in damage to insulation materials that are located near to the leak. The insulation materials released may compromise the operation of the emergency core cooling system (ECCS). Insulation material in the form of mineral wool fibre agglomerates (MWFA) maybe transported to the containment sump strainers mounted at the inlet of the emergency cooling pumps, where the insulation fibres may block or penetrate the strainers. In addition to the impact of MWFA on the pressure drop across the strainers, corrosion products formed over time may also accumulate in the fibre cakes on the strainers, which can lead to a significant increase in the strainer pressure drop and result in cavitation in the ECCS. Thus, knowledge of transport characteristics of the damaged insulation materials in various scenarios is required to help plan for the long-term operability of nuclear reactors, which undergo LOCA. An experimental and theoretical study performed by the Helmholtz-Zentrum Dresden-Rossendorf and the Hochschule Zittau/Görlitz1 is investigating the phenomena that maybe observed in the containment vessel during a LOCA. The study entails the generation of fibre agglomerates, the determination of their transport properties in single and multi-effect experiments and the long-term effect that corrosion of the containment internals by the coolant has on the strainer pressure drop. The focus of this presentation is on the experiments performed that characterize the horizontal transport of MWFA, whereas the corresponding CFD simulations are described in an accompanying contribution (see abstract of Cartland Glover et al.). The experiments were performed a racetrack type channel that provided a near uniform horizontal flow. The channel is 0.1 wide by 1.2 m high with a straight length of 5 m and two bends of 0.5 m. The measurement techniques include particle imaging (both wide-angle and macro lens), concurrent particle image velocimetry, ultravelocimetry, laser detection sensors to sense the presence of absence of MWFA and pertinent measurements of the MWFA concentration and quiescent settling characteristics. The transport of the MWFA was observed at velocities of 0.1 and 0.25 m s-1 to verify numerical model behaviour in and just beyond expected velocities in the containment sump of a nuclear reactor.

Privatisation and sustainable competitive advantage in the emerging economies of Central Europe

Extant research on the impact of privatization in the Central Europe (CE) region has focused on improvements in efficiency and the nature of cost-based advantages. This study argues that the development of a vibrant privatized sector requires attention to the broader resource configurations of domestic enterprises. Empirical research was conducted on a large sample of firms in Poland, Hungary and Slovenia. Foreign investment was found to significantly impact on resource accumulation with implications for the development of strategic capabilities and competitive advantage. Foreign direct investment is an effective vehicle for the transfer of financial resources, reputation and new brands but not organizational capabilities. In terms of practice, this study demonstrates the important role of outside investment in the development of a firm's resource base (Frydman et al. 1999). Companies can gain a competitive advantage in their domestic markets through gaining access to the resources of foreign investors.

The impact of architecture on the performance of artificial neural networks

A number of researchers have investigated the impact of network architecture on the performance of artificial neural networks. Particular attention has been paid to the impact on the performance of the multi-layer perceptron of architectural issues, and the use of various strategies to attain an optimal network structure. However, there are still perceived limitations with the multi-layer perceptron and networks that employ a different architecture to the multi-layer perceptron have gained in popularity in recent years, particularly, networks that implement a more localised solution, where the solution in one area of the problem space does not impact, or has a minimal impact, on other areas of the space. In this study, we discuss the major architectural issues affecting the performance of a multi-layer perceptron, before moving on to examine in detail the performance of a new localised network, namely the bumptree. The work presented here examines the impact on the performance of artificial neural networks of employing alternative networks to the long established multi-layer perceptron. In particular, networks that impose a solution where the impact of each parameter in the final network architecture has a localised impact on the problem space being modelled are examined. The alternatives examined are the radial basis function and bumptree neural networks, and the impact of architectural issues on the performance of these networks is examined. Particular attention is paid to the bumptree, with new techniques for both developing the bumptree structure and employing this structure to classify patterns being examined.

The use of anticholinergic agents to treat excessive oropharyngeal and tracheal secretions in palliative care

Palliative care involves a multi-professional team approach to the provision of active, holistic care for patients and their families when the patient's disease is no longer responsive to curative treatment. Patient care encompasses medical and pharmacological intervention for symptom control, together with psychological, spiritual and social support for patients and families. Care is provided by teams in hospice, hospital or community environments. Although traditionally associated with providing care for cancer patients, palliative care services are increasingly providing for patients with non-malignant disease. Symptoms commonly associated with terminal phase of disease include pain, nausea, agitation, respiratory symptoms and general fatigue. During the last few days of life, patients may become weak, resulting in difficulty taking oral medication and have periods of unconsciousness. Some patients may require drug administration via subcutaneous infusion. A proportion of patients may develop difficulty clearing respiratory secretions causing a characteristic ‘death rattle’, which although not generally considered to be distressing for the patient, is often treated with a variety of anticholinergic drugs in an attempt to reduce the ‘noisy breathing’ for the benefit of relatives and others who may be closely associated with the patient.This study examined treatment of death rattle in two Hospices focusing on objective and subjective outcome measures in order to determine the efficacy of anticholinergic regimens in current use. Qualitative methods were employed to elicit attitudes of professionals and carers working closely with the patient. The number of patients recruited and monitored were small, many confounding factors were identified which questioned firstly the clinical rationale for administering anticholinergic drugs routinely to treat death rattle and secondly, the ethics of administering drug regimens to patients to treat death rattle with the primary aim of relieving distress for others. Ethnical issues, including those of consent are discussed in relation to their impact on the methodology of end of life studies in medicines management in palliative care.

Composite materials impact damage detection using neural networks

This thesis considers two basic aspects of impact damage in composite materials, namely damage severity discrimination and impact damage location by using Acoustic Emissions (AE) and Artificial Neural Networks (ANNs). The experimental work embodies a study of such factors as the application of AE as Non-destructive Damage Testing (NDT), and the evaluation of ANNs modelling. ANNs, however, played an important role in modelling implementation. In the first aspect of the study, different impact energies were used to produce different level of damage in two composite materials (T300/914 and T800/5245). The impacts were detected by their acoustic emissions (AE). The AE waveform signals were analysed and modelled using a Back Propagation (BP) neural network model. The Mean Square Error (MSE) from the output was then used as a damage indicator in the damage severity discrimination study. To evaluate the ANN model, a comparison was made of the correlation coefficients of different parameters, such as MSE, AE energy, AE counts, etc. MSE produced an outstanding result based on the best performance of correlation. In the second aspect, a new artificial neural network model was developed to provide impact damage location on a quasi-isotropic composite panel. It was successfully trained to locate impact sites by correlating the relationship between arriving time differences of AE signals at transducers located on the panel and the impact site coordinates. The performance of the ANN model, which was evaluated by calculating the distance deviation between model output and real location coordinates, supports the application of ANN as an impact damage location identifier. In the study, the accuracy of location prediction decreased when approaching the central area of the panel. Further investigation indicated that this is due to the small arrival time differences, which defect the performance of ANN prediction. This research suggested increasing the number of processing neurons in the ANNs as a practical solution.

Micromechanics of agglomerate damage processes

This thesis reports a detailed investigation of the micromechanics of agglomerate behaviour under free-fall impact, double (punch) impact and diametrical compression tests using the simulation software TRUBAL. The software is based on the discrete element method (DEM) which incorporates the Newtonian equations of motion and contact mechanics theory to model the interparticle interactions. Four agglomerates have been used: three dense (differing in interface energy and contact density) and one loose. Although the simulated agglomerates are relatively coarse-grained, the results obtained are in good agreement with laboratory test results reported in the literature. The computer simulation results show that, in all three types of test, the loose agglomerate cannot fracture as it is unable to store sufficient elastic energy. Instead, it becomes flattened for low loading-rates and shattered or crushed at higher loading-rates. In impact tests, the dense agglomerates experience only local damage at low impact velocities. Semi-brittle fracture and fragmentation are produced over a range of higher impact velocities and at very high impact velocities shattering occurs. The dense agglomerates fracture in two or three large fragments in the diametrical compression tests. Local damage at the agglomerate-platen interface always occurs prior to fracture and consists of local bond breakage (microcrack formation) and local dislocations (compaction). The fracture process is dynamic and much more complex than that suggested by continuum fracture mechanics theory. Cracks are always initiated from the contact zones and propagate towards the agglomerate centre. Fracture occurs a short time after the start of unloading when a fracture crack "selection" process takes place. The detailed investigation of the agglomerate damage processes includes an examination of the evolution of the fracture surface. Detailed comparisons of the behaviour of the same agglomerate in all three types of test are presented. The particle size distribution curves of the debris are also examined, for both free-fall and double impact tests.

Numerical modelling of agglomerate degradation

In the processing industries particulate materials are often in the form of powders which themselves are agglomerations of much smaller sized particles. During powder processing operations agglomerate degradation occurs primarily as a result of collisions between agglomerates and between agglomerates and the process equipment. Due to the small size of the agglomerates and the very short duration of the collisions it is currently not possible to obtain sufficiently detailed quantitative information from real experiments to provide a sound theoretically based strategy for designing particles to prevent or guarantee breakage. However, with the aid of computer simulated experiments, the micro-examination of these short duration dynamic events is made possible. This thesis presents the results of computer simulated experiments on a 2D monodisperse agglomerate in which the algorithms used to model the particle-particle interactions have been derived from contact mechanics theories and, necessarily, incorporate contact adhesion. A detailed description of the theoretical background is included in the thesis. The results of the agglomerate impact simulations show three types of behaviour depending on whether the initial impact velocity is high, moderate or low. It is demonstrated that high velocity impacts produce extensive plastic deformation which leads to subsequent shattering of the agglomerate. At moderate impact velocities semi-brittle fracture is observed and there is a threshold velocity below which the agglomerate bounces off the wall with little or no visible damage. The micromechanical processes controlling these different types of behaviour are discussed and illustrated by computer graphics. Further work is reported to demonstrate the effect of impact velocity and bond strength on the damage produced. Empirical relationships between impact velocity, bond strength and damage are presented and their relevance to attrition and comminution is discussed. The particle size distribution curves resulting from the agglomerate impacts are also provided. Computer simulated diametrical compression tests on the same agglomerate have also been carried out. Simulations were performed for different platen velocities and different bond strengths. The results show that high platen velocities produce extensive plastic deformation and crushing. Low platen velocities produce semi-brittle failure in which cracks propagate from the platens inwards towards the centre of the agglomerate. The results are compared with the results of the agglomerate impact tests in terms of work input, applied velocity and damage produced.

The autonomous navigation of an electric vehicle

A navigation and positioning system for an electric automatic guided vehicle has been designed and implemented on an industrial pallet truck. The system includes an optical sensor mounted on the vehicle, capable of recognizing special markers at a distance of 0.3m. Software implemented in a z-80 microprocessor controls the sensor, performs all data processing and contains the decision making processes necessary for the vehicle to navigate its way to its task location. A second microprocessor is used to control the vehicle's drive motors under instruction from the navigation unit, to accurately position the vehicle at its destination. The sensor reliably recognises markers at vehicle speeds up to 1ms- 1, and the system has been integrated into a multiprocessor controlled wire-guidance system and applied to a prototype vehicle.

The development of an expert system for the identification anodic coating process defects as a contribution to the dissemination of anodizing technology

Initially this thesis examines the various mechanisms by which technology is acquired within anodizing plants. In so doing the history of the evolution of anodizing technology is recorded, with particular reference to the growth of major markets and to the contribution of the marketing efforts of the aluminium industry. The business economics of various types of anodizing plants are analyzed. Consideration is also given to the impact of developments in anodizing technology on production economics and market growth. The economic costs associated with work rejected for process defects are considered. Recent changes in the industry have created conditions whereby information technology has a potentially important role to play in retaining existing knowledge. One such contribution is exemplified by the expert system which has been developed for the identification of anodizing process defects. Instead of using a "rule-based" expert system, a commercial neural networks program has been adapted for the task. The advantages of neural networks over 'rule-based' systems is that they are better suited to production problems, since the actual conditions prevailing when the defect was produced are often not known with certainty. In using the expert system, the user first identifies the process stage at which the defect probably occurred and is then directed to a file enabling the actual defects to be identified. After making this identification, the user can consult a database which gives a more detailed description of the defect, advises on remedial action and provides a bibliography of papers relating to the defect. The database uses a proprietary hypertext program, which also provides rapid cross-referencing to similar types of defect. Additionally, a graphics file can be accessed which (where appropriate) will display a graphic of the defect on screen. A total of 117 defects are included, together with 221 literature references, supplemented by 48 cross-reference hyperlinks. The main text of the thesis contains 179 literature references. (DX186565)

Towards a theoretical framework for human performance modelling within manufacturing systems design

The performance of direct workers has a significant impact on the competitiveness of many manufacturing systems. Unfortunately, system designers are ill equipped to assess this impact during the design process. An opportunity exists to assist designers by expanding the capabilities of popular simulation modelling tools, and using them as a vehicle to better consider human factors during the process of system design manufacture. To support this requirement, this paper reports on an extensive review of literature that develops a theoretical framework, which summarizes the principal factors and relationships that such a modelling tool should incorporate.

Protestantism, nation and diaspora in Imperial Germany

This article examines the close connection between Protestantism and nationalism in Imperial Germany within a transnational context. In the years before 1914, the Prussian State Church in particular strengthened the legal and organisational framework for an increasing number of diaspora congregations to become attached. These acted as an important vehicle to embed the nationalist rhetoric produced within the Reich into emigrants' notions of belonging. Whilst previous scholarship has noted this connection in general, the article sheds more detailed light on the mechanics and structure, but also on the limits, of this process. Feedback processes from periphery to centre, in turn, had an impact on German national identity construction as that of a nation that was not confined to state borders. Applying a constructionist theoretical framework, the contested question of whether the heterogeneity of Germans abroad allows for the application of the diaspora concept is answered affirmatively.