Acute oxygen sensing: diverse but convergent mechanisms in airway and arterial chemoreceptors

Airway neuroepithelial bodies sense changes in inspired O2, whereas arterial O2 levels are monitored primarily by the carotid body. Both respond to hypoxia by initiating corrective cardiorespiratory reflexes, thereby optimising gas exchange in the face of a potentially deleterious O2 supply. One unifying theme underpinning chemotransduction in these tissues is K+ channel inhibition. However, the transduction components, from O2 sensor to K+ channel, display considerable tissue specificity yet result in analogous end points. Here we highlight how emerging data are contributing to a more complete understanding of O2 chemosensing at the molecular level

In-home and remote use of robotic body surrogates by people with profound motor deficits

By controlling robots comparable to the human body, people with profound motor deficits could potentially perform a variety of physical tasks for themselves, improving their quality of life. The extent to which this is achievable has been unclear due to the lack of suitable interfaces by which to control robotic body surrogates and a dearth of studies involving substantial numbers of people with profound motor deficits. We developed a novel, web-based augmented reality interface that enables people with profound motor deficits to remotely control a PR2 mobile manipulator from Willow Garage, which is a human-scale, wheeled robot with two arms. We then conducted two studies to investigate the use of robotic body surrogates. In the first study, 15 novice users with profound motor deficits from across the United States controlled a PR2 in Atlanta, GA to perform a modified Action Research Arm Test (ARAT) and a simulated self-care task. Participants achieved clinically meaningful improvements on the ARAT and 12 of 15 participants (80%) successfully completed the simulated self-care task. Participants agreed that the robotic system was easy to use, was useful, and would provide a meaningful improvement in their lives. In the second study, one expert user with profound motor deficits had free use of a PR2 in his home for seven days. He performed a variety of self-care and household tasks, and also used the robot in novel ways. Taking both studies together, our results suggest that people with profound motor deficits can improve their quality of life using robotic body surrogates, and that they can gain benefit with only low-level robot autonomy and without invasive interfaces. However, methods to reduce the rate of errors and increase operational speed merit further investigation.Comment: 43 Pages, 13 Figure

Investigation to identify paint coatings resistive to microorganism growth

All selected coatings contain nutrients that support microbial growth and survival. Incorporation of microbiocidal agents into coatings more susceptible to attack is recommended for improved inhibition of microorganism growth and for increased protection against deterioration of coatings by microorganisms

Designing transition paths for the diffusion of sustainable system innovations. A new potential role for design in transition management?

Copyright @ 2008 Umberto AllemandiIt is a shared opinion that the transition towards sustainability will be a continuous and articulated learning process, which will require radical changes on multiple levels (social, cultural, institutional and technological). It is also shared that, given the nature and the dimension of those changes, a system discontinuity is needed, and that therefore it is necessary to act on a system innovation level. The challenge now is to understand how it is possible to facilitate and support the introduction and diffusion of such innovations. Bringing together insights from both Design for sustainability and Transition management literatures, the paper puts forward a model, called Transition model of evolutionary co-design for sustainable (product-service) system innovations, aimed at facilitating and speed-up the process of designing, experimentation, niche introduction and branching of sustainable such innovations

Extracting Several Resource Deposits of Unknown Size: Optimal Order

Oil companies often announce revised estimates of their reserves. This indicates that stock uncertainty is a prevalent feature of natural resource industries. In this paper we consider the multi-deposit case where resource extraction produces information about the size of reserves. We show that the optimal order of extracting resource deposits depends both on the informational characteristics of the extraction process and on the extraction costs. Differences in extraction costs, a key consideration highlighted in Solow and Wan (1976), must be balanced against the relative value of information generated by the extraction of various deposits. Our model supplies an explanation of why high cost deposits are sometimes extracted when lower cost deposits have not been exhausted. Les compagnies pétrolières révisent souvent les chiffres de leurs réserves, ce qui indique que l’incertitude concernant les stocks est prévalente. Nous considérons le cas où l’extraction donne des informations sur la taille des réserves. Nous prouvons que l’ordre optimal d’exploitation des stocks dépend des propriétés du processus d’extraction concernant la révélation d’information et des coûts. La différence des coûts, qui est une considération importante dans Solow and Wan (1976), doit être balancée contre la valeur informative des réserves. Notre modèle fournit une explication du fait que les réserves plus coûteuses sont parfois exploitées avant l’épuisement des réserves moins coûteuses.order of extraction, value of information, uncertainty, ordre d’extraction, valeur de l’information, incertitude