2,847 research outputs found

    Over-expression of AtPAP2 in Camelina sativa leads to faster plant growth and higher seed yield

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    <p>Abstract</p> <p>Background</p> <p>Lipids extracted from seeds of <it>Camelina sativa </it>have been successfully used as a reliable source of aviation biofuels. This biofuel is environmentally friendly because the drought resistance, frost tolerance and low fertilizer requirement of <it>Camelina sativa </it>allow it to grow on marginal lands. Improving the species growth and seed yield by genetic engineering is therefore a target for the biofuels industry. In <it>Arabidopsis</it>, overexpression of purple acid phosphatase 2 encoded by <it>Arabidopsis </it>(<it>AtPAP2</it>) promotes plant growth by modulating carbon metabolism. Overexpression lines bolt earlier and produce 50% more seeds per plant than wild type. In this study, we explored the effects of overexpressing AtPAP2 in <it>Camelina sativa</it>.</p> <p>Results</p> <p>Under controlled environmental conditions, overexpression of AtPAP2 in <it>Camelina sativa </it>resulted in longer hypocotyls, earlier flowering, faster growth rate, higher photosynthetic rate and stomatal conductance, increased seed yield and seed size in comparison with the wild-type line and null-lines. Similar to transgenic <it>Arabidopsis</it>, activity of sucrose phosphate synthase in leaves of transgenic <it>Camelina </it>was also significantly up-regulated. Sucrose produced in photosynthetic tissues supplies the building blocks for cellulose, starch and lipids for growth and fuel for anabolic metabolism. Changes in carbon flow and sink/source activities in transgenic lines may affect floral, architectural, and reproductive traits of plants.</p> <p>Conclusions</p> <p>Lipids extracted from the seeds of <it>Camelina sativa </it>have been used as a major constituent of aviation biofuels. The improved growth rate and seed yield of transgenic <it>Camelina </it>under controlled environmental conditions have the potential to boost oil yield on an area basis in field conditions and thus make <it>Camelina</it>-based biofuels more environmentally friendly and economically attractive.</p

    Meeting the care priorities of people with rheumatic and musculoskeletal conditions : priorities for action

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    We would like to thank the Nuffield Foundation Oliver Bird Fund who have funded the RHEUMAPs study, and our patient partners and study collaborators for generously giving their time and who have supported this work by designing the survey, taking part in interviews, providing advice, and commenting on drafts

    Contrasting charge-carrier dynamics across key metal-halide perovskite compositions through in situ simultaneous probes

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    Metal-halide perovskites have proven to be a versatile group of semiconductors for optoelectronic applications, with ease of bandgap tuning and stability improvements enabled by halide and cation mixing. However, such compositional variations can be accompanied by significant changes in their charge-carrier transport and recombination regimes that are still not fully understood. Here, a novel combinatorial technique is presented to disentangle such dynamic processes over a wide range of temperatures, based on transient free-space, high-frequency microwave conductivity and photoluminescence measurements conducted simultaneously in situ. Such measurements are used to reveal and contrast the dominant charge-carrier recombination pathways for a range of key compositions: prototypical methylammonium lead iodide perovskite (MAPbI3), the stable mixed formamidinium-caesium lead-halide perovskite FA0.83Cs0.17PbBr0.6I2.4 targeted for photovoltaic tandems with silicon, and fully inorganic wide-bandgap CsPbBr3 aimed toward light sources and X-ray detector applications. The changes in charge-carrier dynamics in FA0.83Cs0.17PbBr0.6I2.4 across temperatures are shown to be dominated by radiative processes, while those in MAPbI3 are governed by energetic disorder at low temperatures, low-bandgap minority-phase inclusions around the phase transition, and non-radiative processes at room temperature. In contrast, CsPbBr3 exhibits significant charge-carrier trapping at low and high temperatures, highlighting the need for improvement of material processing techniques for wide-bandgap perovskites

    End-Effector Contact and Force Detection for Miniature Autonomous Robots Performing Lunar and Expeditionary Surgery

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    Introduction: The U.S. Space Force was stood up on December 20, 2019 as an independent branch under the Air Force consisting of about 16,000 active duty and civilian personnel focused singularly on space. In addition to the Space Force, the plans by NASA and private industry for exploration-class long-duration missions to the moon, near-earth asteroids, and Mars makes semi-independent medical capability in space a priority. Current practice for space-based medicine is limited and relies on a “life-raft” scenario for emergencies. Discussions by working groups on military space-based medicine include placing a Role III equivalent facility in a lunar surface station. Surgical capability is a key requirement for that facility. Materials and Methods: To prepare for the eventuality of surgery in space, it is necessary to develop low-mass, low power, mini-surgical robots, which could serve as a celestial replacement for existing terrestrial robots. The current study focused on developing semi-autonomous capability in surgical robotics, specifically related to task automation. Two categories for end-effector tissue interaction were developed: Visual feedback from the robot to detect tissue contact, and motor current waveform measurements to detect contact force. Results: Using a pixel-to-pixel deep neural network to train, we were able to achieve an accuracy of nearly 90% for contact/nocontact detection. Large torques were predicted well by a trained long short-term memory recursive network, but the technique did not predict small torques well. Conclusion: Surgical capability on long-duration missions will require human/machine teaming with semi-autonomous surgical robots. Our existing small, lightweight, low-power miniature robots perform multiple essential tasks in one design including hemostasis, fluid management, suturing for traumatic wounds, and are fully insertable for internal surgical procedures. To prepare for the inevitable eventuality of an emergency surgery in space, it is essential that automated surgical robot capabilities be developed

    Engaging with community researchers for exposure science: lessons learned from a pesticide biomonitoring study

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    A major challenge in biomonitoring studies with members of the general public is ensuring their continued involvement throughout the necessary length of the research. The paper presents evidence on the use of community researchers, recruited from local study areas, as a mechanism for ensuring effective recruitment and retention of farmer and resident participants for a pesticides biomonitoring study. The evidence presented suggests that community researchers' abilities to build and sustain trusting relationships with participants enhanced the rigour of the study as a result of their on-the-ground responsiveness and flexibility resulting in data collection beyond targets expected
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