108 research outputs found

    Shared Autonomy via Hindsight Optimization

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    In shared autonomy, user input and robot autonomy are combined to control a robot to achieve a goal. Often, the robot does not know a priori which goal the user wants to achieve, and must both predict the user's intended goal, and assist in achieving that goal. We formulate the problem of shared autonomy as a Partially Observable Markov Decision Process with uncertainty over the user's goal. We utilize maximum entropy inverse optimal control to estimate a distribution over the user's goal based on the history of inputs. Ideally, the robot assists the user by solving for an action which minimizes the expected cost-to-go for the (unknown) goal. As solving the POMDP to select the optimal action is intractable, we use hindsight optimization to approximate the solution. In a user study, we compare our method to a standard predict-then-blend approach. We find that our method enables users to accomplish tasks more quickly while utilizing less input. However, when asked to rate each system, users were mixed in their assessment, citing a tradeoff between maintaining control authority and accomplishing tasks quickly

    Cellular Procoagulant Activity Dictates Clot Structure and Stability as a Function of Distance From the Cell Surface

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    Thrombin concentration modulates fibrin structure and fibrin structure modulates clot stability; however, the impact of localized, cell surface-driven in situ thrombin generation on fibrin structure and stability has not previously been evaluated

    High Elmo1 expression aggravates and low Elmo1 expression prevents diabetic nephropathy

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    About one-third of patients with type 1 diabetes mellitus develop nephropathy, which often progresses to end-stage renal diseases. The present study demonstrates that below-normal Elmo1 expression in mice ameliorates the albuminuria and glomerular histological changes resulting from long-standing type 1 diabetes, whereas above-normal Elmo1 expression makes both worse. Increasing Elmo1 expression leads to aggravation of oxidative stress markers and enhances the expression of fibrogenic genes. Suppressing Elmo1 action in human patients could be a promising option for treating/preventing the progressive deterioration of renal function in diabetes

    Dental therapists in general dental practice. A literature review and case study analysis to determine what works, why, how and in what circumstances

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    Introduction In the United Kingdom, policy and guidance changes regarding the role of Dental Therapists (DTs) were implemented in recent years with a view to changing dental care to a more preventive‐focussed, teamwork approach. However, success in the adoption of this model of working has been varied. Aims Adopting a realist approach, our aim was, to examine the use of DTs in general dental practices in Wales, exploring what works, why, how and in what circumstances. Materials and Methods The research comprised two stages. (i) A structured literature search, dual‐coding papers for high‐level factors describing the conditions or context(s) under which the mechanisms operated to produce outcomes. From this, we derived theories about how skill‐mix operates in the general dental service. (ii) Six case studies of general dental practices (three with a Dental Therapist/three without a Dental Therapist) employing a range of skill‐mix models incorporating semi‐structured interviews with all team members. We used the case studies/interviews to explore and refine the theories derived from the literature. Results Eighty‐four papers were coded. From this coding, we identified seven theories which reflected factors influencing general dental practices within three broad contexts: the dental practice as a business, as a healthcare provider, and as a workplace. We tested these theories in interviews with 38 dental team members across the six care studies. As a result, we amended five of the theories. Conclusion Our analysis provides theory about outcomes that DTs may facilitate and the mechanisms that may assist the work of DTs within different contexts of general dental practice

    Low TGFβ1 expression prevents and high expression exacerbates diabetic nephropathy in mice

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    About one third of patients with type 1 diabetes mellitus develop nephropathy, which often progresses to end-stage renal diseases. The present study demonstrates that below normal transforming growth factor (TGF) β1 expression ameliorates the nephropathy and decreased glomerular filtration rate resulting from long-standing type 1 diabetes, while above normal TGFβ1 expression makes both worse. Reducing TGFβ1 expression in the glomerulus is more important in avoiding the decrease in glomerular filtration rate than altering expression in the tubule, while expression in the tubule is more important in controlling interstitial fibrosis and albuminuria. Suppressing TGFβ1 action in the kidney as a whole, or specifically in podocytes, could be a promising option for treating/preventing the progressive deterioration of renal function in diabetes
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