694 research outputs found

    Hürthle cell carcinoma: current perspectives.

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    Hürthle cell carcinoma (HCC) can present either as a minimally invasive or as a widely invasive tumor. HCC generally has a more aggressive clinical behavior compared with the other differentiated thyroid cancers, and it is associated with a higher rate of distant metastases. Minimally invasive HCC demonstrates much less aggressive behavior; lesions <4 cm can be treated with thyroid lobectomy alone, and without radioactive iodine (RAI). HCC has been observed to be less iodine-avid compared with other differentiated thyroid cancers; however, recent data have demonstrated improved survival with RAI use in patients with HCC >2 cm and those with nodal and distant metastases. Patients with localized iodine-resistant disease who are not candidates for a wait-and-watch approach can be treated with localized therapies. Systemic therapy is reserved for patients with progressive, widely metastatic HCC

    BonnBot-I: A Precise Weed Management and Crop Monitoring Platform

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    Cultivation and weeding are two of the primary tasks performed by farmers today. A recent challenge for weeding is the desire to reduce herbicide and pesticide treatments while maintaining crop quality and quantity. In this paper we introduce BonnBot-I a precise weed management platform which can also performs field monitoring. Driven by crop monitoring approaches which can accurately locate and classify plants (weed and crop) we further improve their performance by fusing the platform available GNSS and wheel odometry. This improves tracking accuracy of our crop monitoring approach from a normalized average error of 8.3% to 3.5%, evaluated on a new publicly available corn dataset. We also present a novel arrangement of weeding tools mounted on linear actuators evaluated in simulated environments. We replicate weed distributions from a real field, using the results from our monitoring approach, and show the validity of our work-space division techniques which require significantly less movement (a 50% reduction) to achieve similar results. Overall, BonnBot-I is a significant step forward in precise weed management with a novel method of selectively spraying and controlling weeds in an arable fieldComment: 2022 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS

    A Classification System for Teachers’ Motivational Behaviours Recommended in Self-Determination Theory Interventions

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    Teachers’ behaviour is a key factor that influences students’ motivation. Many theoretical models have tried to explain this influence, with one of the most thoroughly researched being self-determination theory (SDT). We used a Delphi method to create a classification of teacher behaviours consistent with SDT. This is useful because SDT-based interventions have been widely used to improve educational outcomes. However, these interventions contain many components. Reliably classifying and labelling those components is essential for implementation, reproducibility, and evidence synthesis. We used an international expert panel (N = 34) to develop this classification system. We started by identifying behaviours from existing literature, then refined labels, descriptions, and examples using the Delphi panel’s input. Next, the panel of experts iteratively rated the relevance of each behaviour to SDT, the psychological need that each behaviour influenced, and its likely effect on motivation. To create a mutually exclusive and collectively exhaustive list of behaviours, experts nominated overlapping behaviours that were redundant, and suggested new ones missing from the classification. After three rounds, the expert panel agreed upon 57 teacher motivational behaviours that were consistent with SDT. For most behaviours (77%), experts reached consensus on both the most relevant psychological need and influence on motivation. Our classification system provides a comprehensive list of teacher motivational behaviours and consistent terminology in how those behaviours are labelled. Researchers and practitioners designing interventions could use these behaviours to design interventions, to reproduce interventions, to assess whether these behaviours moderate intervention effects, and could focus new research on areas where experts disagree

    Design and experimental characterization of a tunable vibration-based electromagnetic micro-generator

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    Vibration-based micro-generators, as an alternative source of energy, have become increasingly significant in the last decade. This paper presents a new tunable electromagnetic vibration-based micro-generator. Frequency tuning is realized by applying an axial tensile force to the micro-generator. The dimensions of the generator, especially the dimensions of the coil and the air gap between magnets, have been optimized to maximize the output voltage and power of the micro-generator. The resonant frequency has been successfully tuned from 67.6 to 98 Hz when various axial tensile forces were applied to the structure. The generator produced a power of 61.6–156.6 µW over the tuning range when excited at vibrations of 0.59 ms-2. The tuning mechanism has little effect on the total damping. When the tuning force applied on the generator becomes larger than the generator’s inertial force, the total damping increases resulting in reduced output power. The resonant frequency increases less than indicated from simulation and approaches that of a straight tensioned cable when the force associated with the tension in the beam becomes much greater than the beam stiffness. The test results agree with the theoretical analysis presented