377 research outputs found

    Quantitative Information For Strategic Decisions

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    For the past 10 years, if not 20, the prophets of management science have been forecasting the arrival of the quantitative era. This millennium is to be achieved through the use of mathematical models and statistical techniques as programed into computers. For example, in 1961 one of the foremost management scientist predicted, Management education and practice are, I believe, on the verge of a major breakthrough in understanding quantitatively how industrial company success depends on the interaction between the flows of information, orders, materials, money, personnel and capital equipment

    Lo-fi prototyping to design interactive-tabletop applications for children

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    Interactive tabletops are an exiting new platform for supporting children's collaboration. With design guidelines and standardized interaction principles still immature, there is a considerable need for iterative prototyping to define the task and interface. Lo-fi prototypes-using cardboard, paper, etc.- are easy to develop, flexible to adjust during design sessions, and intuitive for users to manipulate. Using them can be a valuable step in designing tabletop applications. In this paper, we detail the design process of two tabletop applications, concentrating on the role of lo-fi prototyping. TransTime is a pattern game for 5-6 year olds to engage how time progresses. OurSpace is a design tool for 7-9 year olds to arrange desks and assign seats for students in their classroom. By comparing the experiences, we arrive at a better understanding of the benefits, challenges, and limits of using lo-fi prototypes to design interactive-tabletop applications for children

    Nitric oxide suppresses cerebral vasomotion by sGC-independent effects on ryanodine receptors and voltage-gated calcium channels

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    Background/Aims: In cerebral arteries, nitric oxide (NO) release plays a key role in suppressing vasomotion. Our aim was to establish the pathways affected by NO in rat middle cerebral arteries. Methods: In isolated segments of artery, isometric tension and simultaneous measurements of either smooth muscle membrane potential or intracellular [Ca 2+ ] ([Ca 2+ ] SMC ) changes were recorded. Results: In the absence of L -NAME, asynchronous propagating Ca 2+ waves were recorded that were sensitive to block with ryanodine, but not nifedipine. L -NAME stimulated pronounced vasomotion and synchronous Ca 2+ oscillations with close temporal coupling between membrane potential, tone and [Ca 2+ ] SMC . If nifedipine was applied together with L -NAME, [Ca 2+ ] SMC decreased and synchronous Ca 2+ oscillations were lost, but asynchronous propagating Ca 2+ waves persisted. Vasomotion was similarly evoked by either iberiotoxin, or by ryanodine, and to a lesser extent by ODQ. Exogenous application of NONOate stimulated endothelium-independent hyperpolarization and relaxation of either L -NAME-induced or spontaneous arterial tone. NO-evoked hyperpolarization involved activation of BK Ca channels via ryanodine receptors (RYRs), with little involvement of sGC. Further, in whole cell mode, NO inhibited current through L-type voltage-gated Ca 2+ channels (VGCC), which was independent of both voltage and sGC. Conclusion: NO exerts sGC-independent actions at RYRs and at VGCC, both of which normally suppress cerebral artery myogenic tone

    The response of the tandem pore potassium channel TASK-3 (K2P9.1) to voltage : gating at the cytoplasmic mouth

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    Although the tandem pore potassium channel TASK-3 is thought to open and shut at its selectivity filter in response to changes of extracellular pH, it is currently unknown whether the channel also shows gating at its inner, cytoplasmic mouth through movements of membrane helices M2 and M4.We used two electrode voltage clamp and single channel recording to show that TASK-3 responds to voltage in a way that reveals such gating. In wild-type channels, Popen was very low at negative voltages, but increased with depolarisation. The effect of voltage was relatively weak and the gating charge small, ∼0.17.Mutants A237T (in M4) and N133A (in M2) increased Popen at a given voltage, increasing mean open time and the number of openings per burst. In addition, the relationship between Popen andvoltagewas shifted to lesspositive voltages. Mutation of putative hinge glycines (G117A, G231A), residues that are conserved throughout the tandem pore channel family, reduced Popen at a given voltage, shifting the relationship with voltage to a more positive potential range. None of these mutants substantially affected the response of the channel to extracellular acidification. We have used the results from single channel recording to develop a simple kinetic model to show how gating occurs through two classes of conformation change, with two routes out of the open state, as expected if gating occurs both at the selectivity filter and at its cytoplasmic mouth

    The relative efficiency of automatic and discretionary regional aid

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    For the last two decades, the primary instruments for UK regional policy have been discretionary subsidies. Such aid is targeted at "additional" projects - projects that would not have been implemented without the subsidy - and the subsidy should be the minimum necessary for the project to proceed. Discretionary subsidies are thought to be more efficient than automatic subsidies, where many of the aided projects are non-additional and all projects receive the same subsidy rate. The present paper builds on Swales (1995) and Wren (2007a) to compare three subsidy schemes: an automatic scheme and two types of discretionary scheme, one with accurate appraisal and the other with appraisal error. These schemes are assessed on their expected welfare impacts. The particular focus is the reduction in welfare gain imposed by the interaction of appraisal error and the requirements for accountability. This is substantial and difficult to detect with conventional evaluation techniques

    Clinicians’ perspectives and experiences of providing cervical ripening at home or in-hospital in the United Kingdom

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    Acknowledgements We are grateful to those who gave their time for interviews and focus groups despite the severe workload pressures and ongoing COVID-19 pandemic. CHOICE is funded by the National Institute of Healthcare Research Health Technology and Assessment (NIHR HTA) NIHR 127569. SJS is funded by a Wellcome Trust Clinical Career Development Fellowship (209560/Z/17/Z). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The views expressed are those of the authors and not necessarily those of the National Institute of Healthcare Research or the Department of Health and Social Care.Peer reviewedPublisher PD

    New Challenges in Psycho-Oncology Research III: A systematic review of psychological interventions for prostate cancer survivors and their partners: clinical and research implications

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    Abstract not availableSuzanne K. Chambers, Melissa K. Hyde, David P. Smith, Suzanne Hughes, Susan Yuill, Sam Egger, Dianne L. O'Connell, Kevin Stein, Mark Frydenberg, Gary Wittert, Jeff Dun

    The selectivity, voltage-dependence and acid sensitivity of the tandem pore potassium channel TASK-1 : contributions of the pore domains

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    We have investigated the contribution to ionic selectivity of residues in the selectivity filter and pore helices of the P1 and P2 domains in the acid sensitive potassium channel TASK-1. We used site directed mutagenesis and electrophysiological studies, assisted by structural models built through computational methods. We have measured selectivity in channels expressed in Xenopus oocytes, using voltage clamp to measure shifts in reversal potential and current amplitudes when Rb+ or Na+ replaced extracellular K+. Both P1 and P2 contribute to selectivity, and most mutations, including mutation of residues in the triplets GYG and GFG in P1 and P2, made channels nonselective. We interpret the effects of these—and of other mutations—in terms of the way the pore is likely to be stabilised structurally. We show also that residues in the outer pore mouth contribute to selectivity in TASK-1. Mutations resulting in loss of selectivity (e.g. I94S, G95A) were associated with slowing of the response of channels to depolarisation. More important physiologically, pH sensitivity is also lost or altered by such mutations. Mutations that retained selectivity (e.g. I94L, I94V) also retained their response to acidification. It is likely that responses both to voltage and pH changes involve gating at the selectivity filter

    Playful learning with sound-augmented toys: a comparison between children with and without visual impairments.

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    Sound-augmented toys producing factual knowledge were thought to encourage incidental, playful learning in children with visual impairments (VIs). A group of15 children with VIs and 22 sighted controls played with a sound-augmented savannah landscape and listened to an informative story in a counterbalanced order. Children's knowledge about savannah animals was assessed at baseline and after each condition in order to quantitatively compare knowledge gains between conditions.Results indicated that children with VIs gained more knowledge than sighted controls from playing with the sound-augmented toy. Furthermore, offering both the augmented toy and the informative story led to higher knowledge gains than a single medium, especially in children with VIs. Sound-augmented toys could therefore be a useful addition to the current curriculum in special education for children with VIs

    Mechanisms for collaboration: a design and evaluation framework for multi-user interfaces

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    Multi-user interfaces are said to provide “natural” interaction in supporting collaboration, compared to individual and noncolocated technologies. We identify three mechanisms accounting for the success of such interfaces: high awareness of others' actions and intentions, high control over the interface, and high availability of background information. We challenge the idea that interaction over such interfaces is necessarily “natural” and argue that everyday interaction involves constraints on awareness, control, and availability. These constraints help people interact more smoothly. We draw from social developmental psychology to characterize the design of multi-user interfaces in terms of how constraints on these mechanisms can be best used to promote collaboration. We use this framework of mechanisms and constraints to explain the successes and failures of existing designs, then apply it to three case studies of design, and finally derive from them a set of questions to consider when designing and analysing multi-user interfaces for collaboration
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