695 research outputs found

    Co-transport-induced instability of membrane voltage in tip-growing cells

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    A salient feature of stationary patterns in tip-growing cells is the key role played by the symports and antiports, membrane proteins that translocate two ionic species at the same time. It is shown that these co-transporters destabilize generically the membrane voltage if the two translocated ions diffuse differently and carry a charge of opposite (same) sign for symports (antiports). Orders of magnitude obtained for the time and lengthscale are in agreement with experiments. A weakly nonlinear analysis characterizes the bifurcation

    Influence of duration of dietary vitamin E supplementation on swine growth performance and carcass quality

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    Supplementing medium-lean genotype pigs with supranutritional concentrations of dietary vitamin E (91 IU d-a-tocopheryl acetate/lb of feed) for as long as 70 d during the finishing phase was not effective in improving swine performance, feeding characteristics, and 24 h loin muscle quality. However, lower carcass temperatures obtained by spray chilling pork sides at O°C versus 4.4°C had a beneficial effect on 24 h carcass quality by improving marbling and lean firmness scores and reducing loin muscle moisture exudate. Overall, 24 h pork carcass quality was impacted more by chill rate than dietary vitamin E supplementation.; Swine Day, Manhattan, KS, November 19, 199

    Towards high-temperature coherence-enhanced transport in heterostructures of a few atomic layers

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    The possibility to exploit quantum coherence to strongly enhance the efficiency of charge transport in solid state devices working at ambient conditions would pave the way to disruptive technological applications. In this work, we tackle the problem of the quantum transport of photogenerated electronic excitations subject to dephasing and on-site Coulomb interactions. We show that the transport to a continuum of states representing metallic collectors can be optimized by exploiting the "superradiance" phenomena. We demonstrate that this is a coherent effect which is robust against dephasing and electron-electron interactions in a parameters range that is compatible with actual implementation in few-monolayer transition-metal-oxide (TMO) heterostructures

    Visceral leishmaniasis patients display altered composition and maturity of neutrophils as well as impaired neutrophil effector functions

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    Immunologically, active visceral leishmaniasis (VL) is characterised by profound immunosuppression, severe systemic inflammatory responses and an impaired capacity to control parasite replication. Neutrophils are highly versatile cells, which play a crucial role in the induction as well as the resolution of inflammation, the control of pathogen replication and the regulation of immune responses. Neutrophil functions have been investigated in human cutaneous leishmaniasis, however, their role in human visceral leishmaniasis is poorly understood. In the present study we evaluated the activation status and effector functions of neutrophils in patients with active VL and after successful anti-leishmanial treatment. Our results show that neutrophils are highly activated and have degranulated; high levels of arginase, myeloperoxidase and elastase, all contained in neutrophils’ granules, were found in the plasma of VL patients. In addition, we show that a large proportion of these cells are immature. We also analysed effector functions of neutrophils that are essential for pathogen clearance and show that neutrophils have an impaired capacity to release neutrophil extracellular traps, produce reactive oxygen species and phagocytose bacterial particles, but not Leishmania parasites. Our results suggest that impaired effector functions, increased activation and immaturity of neutrophils play a key role in the pathogenesis of VL

    A Conceptual framework for Adaptive User Interfaces for older adults

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    The file attached to this record is the author's final peer reviewed version.Nowadays, information and communication technologies (ICT) have become part of our everyday life, enhancing the quality of life and promoting new forms of social interaction. Despite the numerous benefits of ICT, older adults still present low rates of ICT adoption compared to other population segments. The lack of accessible User Interfaces has been identified as a major barrier. Traditional User Interfaces follow a design for all approach, typically ignoring the needs of older adults. Recent research in Human-Computer Interaction (HCI) proposes adaptive User Interfaces to suit the individual users abilities. Nevertheless, most of the existing approaches perform adaptation based on user profile groups and do not provide personalized adaptation in real-time. This paper introduces a conceptual framework for developing real-time adaptive User Interfaces. The system aims to target most common issues among older adults, i.e. cognitive decline and vision loss. The developed conceptual framework also presents novel strategic techniques to assess cognitive load and vision related issues in an unobtrusive manner for the use

    ACL graft re-rupture after double-bundle reconstruction: factors that influence the intra-articular pattern of injury

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    To determine the most common rupture patterns of previously reconstructed DB-ACL cases, seen at the time of revision surgery, and to determine the influence of age, gender, time between the initial ACL reconstruction and re-injury, tunnel angle and etiology of failure. Forty patients who presented for revision surgery after previous double-bundle ACL reconstruction were enrolled. Three orthopedic surgeons independently reviewed the arthroscopic videos and determined the rupture pattern of both the anteromedial and posterolateral grafts. The graft rupture pattern was then correlated with the previously mentioned factors. The most common injury pattern seen at the time of revision ACL surgery was mid-substance AM and PL bundle rupture. Factors that influenced the rupture pattern (proximal vs. mid-substance and distal rupture vs. elongated, but in continuity) were months between ACL reconstruction and re-injury (P = 0.002), the etiology of failure (traumatic vs. atraumatic) (P = 0.025) and the measured graft tunnel angle (P = 0.048). The most common pattern of graft re-rupture was mid-substance AM and mid-substance PL. As the length of time from the initial DB-ACL reconstruction to revision surgery increased, the pattern of injury more closely resembled that of the native ACL. Evaluation of patients who have undergone double-bundle ACL reconstruction, with a particular focus on graft maturity, mechanism of injury and femoral tunnel angles, and graft rupture pattern assists in preoperative planning for revision surger
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