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Networked systems that gather sensor data in order to re act to phenomena in their surroundings are faced with a growing need for adaptive behavior to operate in dynamically changing environments. In designing such a networked system we decompose the data processing chain in distinct functions. These functional components interact by requesting information they need and fulfilling requests that are received from other components. Evaluation of the available data with respect to the different requests and available resources is a key process in each component. A new evaluation method is presented which is capable of balancing the information value against the resource costs of data. An example of cooperating object tracking modules is presented.

Objectives The aim of this study was to investigate which prepartum determinants contribute to the development of postpartum (PP) fatigue among working women in the Netherlands. Methods A prospective cohort study in 15 Dutch companies was conducted to measure different potential predictors using self-administrated questionnaires at baseline and at 30 weeks of pregnancy. Fatigue was measured at 12 (N = 523) and 52 weeks (N = 436) PP using the Checklist Individual Strength (CIS). A CIS score > 76 was defined as fatigue. Results The prevalence of fatigue at 12 and 52 weeks PP was 24.5% and 18.1%, respectively. Fourteen predictive factors were found for fatigue (R2 = 0.37) at 12 weeks PP. Ten predictive factors were found for fatigue at 52 weeks PP (R2 = 0.36). In general, less favourable work relationships and characteristics, poorer mental health, more passive coping styles, more sleeping problems, more fatigue during pregnancy, and beliefs about child care arrangements were related to PP fatigue. At 30 weeks of pregnancy, only more fatigue (OR = 3.69, p < 0.001; OR = 2.68, p = 0.02) and poorer mental health (OR = 0.50, p = 0.02; OR = 0.90, p = 0.78) predicted fatigue both at 12 and 52 weeks PP. Conclusions A large number of predictive factors for PP fatigue were found. These findings indicate that different aspects can contribute to being fatigued after pregnancy. Further research is needed to investigate the effect of possible interventions by employers and/or occupational physicians.

Where exactly do people look when they grasp an object? An object is usually contacted at two locations, whereas the gaze can only be at one location at the time. We investigated participants' fixation locations when they grasp objects with the contact positions of both index finger and thumb being visible and compared these to fixation locations when they only viewed the objects. Participants grasped with the index finger at the top and the thumb at the bottom of a flat shape. The main difference between grasping and viewing was that after a saccade roughly directed to the object's center of gravity, participants saccaded more upward and more into the direction of a region that was difficult to contact during grasping. A control experiment indicated that it was not the upper part of the shape that attracted fixation, while the results were consistent with an attraction by the index finger. Participants did not try to fixate both contact locations. Fixations were closer to the object's center of gravity in the viewing than in the grasping task. In conclusion, participants adapt their eye movements to the need of the task, such as acquiring information about regions with high required contact precision in grasping, even with small (graspable) objects. We suggest that in grasping, the main function of fixations is to acquire visual feedback of the approaching digits. © ARVO.

Background. Individuals claiming a disability benefit after long-term sickness absence, have to undergo medical disability assessments. These assessments, often carried out by specialized physicians, can be complicated by wrong expectations or defensive attitudes of disability benefit claimants. It is hypothesized that empowerment of these claimants will enhance the physician-patient relationship by shifting claimants from a passive role to a more active and constructive role during disability assessments. Furthermore, empowerment of claimants may lead to a more realistic expectation and acceptance of the assessment outcome among claimants and may lead to a more accurate assessment by the physician. Methods/Design. In a two-armed randomized controlled trial (RCT), 230 claimants will be randomized to either the intervention or control group. For the intervention group, an interactive website was designed http://www.wiagesprek.nl using an Intervention Mapping procedure. This website was tested during a pilot study among 51 claimants. The final version of the website consists of five interactive modules, in which claimants will be prepared and empowered step-by-step, prior to their upcoming disability assessment. Other website components are a forum, a personal health record, a personal diary, and information on disability assessment procedures, return to work, and coping with disease and work disability. Subjects from the control group will be directed to a website with commonly available information only. Approximately two weeks prior to their disability assessment, disability claimants will be recruited through the Dutch Workers Insurance Authority (UWV). Outcomes will be assessed at five occasions: directly after recruitment (baseline), prior to disability assessment, directly after disability assessment as well as 6 and 16 weeks after the assessment. The study's primary outcome is empowerment, measured with the Vrijbaan questionnaire. Secondary outcomes include claimants' satisfaction, perceived justice, coping strategy, and knowledge. A process evaluation will also be conducted. Discussion. This study evaluates the effectiveness of an interactive website aimed at empowerment of disability claimants. It is hypothesized that by increasing empowerment, the physician-patient relationship may be enhanced and claimants' satisfaction and perceived justice can be improved. Results are expected in 2010. Trial registration. NTR-1414. © 2009 Samoocha et al; licensee BioMed Central Ltd.

Objectives: To assess the labour market position of patients with ankylosing spondylitis (AS) in relation to disease duration and to identify potential factors in relation to withdrawal from the labour force. Methods: A cross sectional mail survey was conducted among 658 patients with AS. Participation in the labour force was defined as having a paid job. The independent effect of duration of disease was examined by an indirect method of standardisation. A broad variety of risk factors were examined separately and in a combined analysis, including sociodemographic factors, disease related variables, coping styles, and work related factors. Attributable and preventable fractions were calculated from the combined analyses to assess the relative importance of the contributing factors. Results: Probability of participation in the labour force was similarly reduced in patients with AS with different durations of disease. Pacing to cope with limitations was the most relevant factor in increasing the risk of withdrawal from the labour force, accounting for 73% of withdrawals. Coping with limitations by often seeking creative solutions, high disease activity, increased age, and insufficient support from colleagues or management were also positively associated with withdrawal from the labour force. Technical or ergonomic adjustments of the workplace, working in large companies, and coping with dependency style through frequent acceptance were negatively associated. Of these factors, technical or ergonomic adjustment was the most relevant in terms of reducing the risk. Conclusion: Sociodemographic factors, disease related factors, coping styles, and work related factors contribute simultaneously to withdrawal from the labour force.

The aim of this study was to determine the effect of a tactile feedback signal on hovering behaviour, productivity, usability and comfort after 1 week of using an experimental mouse. In a randomized controlled trial, a regular computer mouse was compared to a new developed mouse with a tactile, vibrating feedback signal to prevent unnecessary hovering above the computer mouse. According to this study, participants do decrease their hovering behaviour when using a mouse with tactile feedback. Furthermore, the mouse with tactile feedback did not influence productivity. Usability was rated somewhat mixed. The use of a mouse with a tactile vibrating feedback signal seems promising for preventing neck, shoulder and arm complaints. Further research is needed to study long-term effects on (prevention of) neck, shoulder and arm complaints and development of learning effects.