8 research outputs found

    Markerless visual servoing on unknown objects for humanoid robot platforms

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    To precisely reach for an object with a humanoid robot, it is of central importance to have good knowledge of both end-effector, object pose and shape. In this work we propose a framework for markerless visual servoing on unknown objects, which is divided in four main parts: I) a least-squares minimization problem is formulated to find the volume of the object graspable by the robot's hand using its stereo vision; II) a recursive Bayesian filtering technique, based on Sequential Monte Carlo (SMC) filtering, estimates the 6D pose (position and orientation) of the robot's end-effector without the use of markers; III) a nonlinear constrained optimization problem is formulated to compute the desired graspable pose about the object; IV) an image-based visual servo control commands the robot's end-effector toward the desired pose. We demonstrate effectiveness and robustness of our approach with extensive experiments on the iCub humanoid robot platform, achieving real-time computation, smooth trajectories and sub-pixel precisions

    Acute pediatric cerebellitis and mutism. Case report and review of the literature

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    Acute cerebellitis (AC) is a rare syndrome characterized by an inflammatory involvement of the cerebellum which can complicate infections or vaccinations. AC can be a life-threatening condition, presenting with speech disorders including longlasting mutism, usually followed by dysarthria. Clinical examination, laboratory findings and Magnetic Resonance Imaging are essential for establishing an early diagnosis and initiating prompt and adequate treatment, thereby reducing morbidity and mortality. We report a case of a child with AC complicated by mutism and we present a review of the literature of pediatric cases with this condition

    Proposal for management of the infant with suspected food protein-induced allergic proctocolitis

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    we hypothesized a different management of child with suspected FPIAP, easier regarding the diet to follow. The management pathway illustrated in Figure 1 is different depending on whether duration of hematochezia is less than/equal to 1 month or higher. We chose 1 month as cutoff because this is the sum of the maximum duration (21 days) of hematochezia during follow- up in children randomly assigned to continue their normal diet and the mean duration (10 days) of bloody stools before admission in the study of Arvola et al4 The most important points of our proposal are two: \u2022 In case of hematochezia with duration less than or equal 1 month, we suggest waiting for the spontaneous resolution without elimination diet; \u2022 In cases of a duration of more than 1 month, we suggest an elimination diet and, if hematochezia disappears, we suggest a challenge

    Comparison of propofol versus propofol-ketamine combination in pediatric oncologic procedures performed by non-anesthesiologists.

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    BACKGROUND: Limited data are available on the best option (short acting sedatives, opioids, or ketamine) in oncologic procedural sedation performed by non-anesthesiologists. The aim of the present prospective study is to compare the safety and efficacy of propofol-ketamine versus propofol alone, managed by trained pediatricians, in children with cancer undergoing painful procedures. PROCEDURES: Data on 121 children with acute lymphatic leukemia (ALL) undergoing procedural sedations (lumbar punctures and bone marrow aspirations) were prospectively collected and included drug doses, side effects, pain assessment, and sedation degree. Children were randomly assigned to one of the two groups: P (n = 62) receiving propofol alone and K (n = 59) in whom a ketamine-propofol combination was used. RESULTS: In group K, the total dose of propofol required was significantly lower than in group P (3.9 ± 3.6 mg/kg vs. 5.1 ± 3.6 mg/kg; P < 0.001). The incidence of hypotension was also significantly lower (11% vs. 39%; P < 0.001). Major O(2) desaturations (defined as SatO(2)  < 88%) occurred principally in group P (7 vs. 1; P = 0.05). Both best analgesia and shorter recovery time were obtained with the propofol-ketamine association. No differences were observed in the degree of sedation and in the awakening quality score between the two groups. CONCLUSIONS: The combination of propofol and ketamine produced statistically significant clinical advantages combined with a higher profile of safety in children with cancer undergoing painful procedures

    RoboCat: A Self-Improving Foundation Agent for Robotic Manipulation

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    The ability to leverage heterogeneous robotic experience from different robots and tasks to quickly master novel skills and embodiments has the potential to transform robot learning. Inspired by recent advances in foundation models for vision and language, we propose a foundation agent for robotic manipulation. This agent, named RoboCat, is a visual goal-conditioned decision transformer capable of consuming multi-embodiment action-labelled visual experience. This data spans a large repertoire of motor control skills from simulated and real robotic arms with varying sets of observations and actions. With RoboCat, we demonstrate the ability to generalise to new tasks and robots, both zero-shot as well as through adaptation using only 100--1000 examples for the target task. We also show how a trained model itself can be used to generate data for subsequent training iterations, thus providing a basic building block for an autonomous improvement loop. We investigate the agent's capabilities, with large-scale evaluations both in simulation and on three different real robot embodiments. We find that as we grow and diversify its training data, RoboCat not only shows signs of cross-task transfer, but also becomes more efficient at adapting to new tasks

    Interobserver reproducibility of cytologic p16INK4a/Ki-67 dual immunostaining in human papillomavirus-positive women

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    BACKGROUND: The accumulation of cyclin-dependent kinase inhibitor 2A (p16(ink4a)) protein in a cell is associated with neoplastic progression in precancerous cervical lesions. Dual staining for p16(ink4a) and Ki-67 has been proposed as a triage test in cervical cancer screening for women who test positive for human papillomavirus DNA. In this study, interobserver reproducibility of the interpretation of this test was assessed. METHODS: Forty-two immunostained, liquid-based cytology slides were divided into 2 sets and were interpreted by 17 to 21 readers from 9 different laboratories, yielding a total of 816 reports. Immunostaining results were classified as positive, negative, inconclusive, or inadequate. After evaluation of the first set of slides and before circulation of the second set, the results were discussed in a plenary meeting. The 10 slides with the most discordant results were evaluated again by selected expert cytopathologists. RESULTS: The overall kappa value was 0.612 (95% confidence interval [CI], 0.523-0.701), it was higher for the positive and negative categories (kappa=0.692 and kappa=0.641, respectively), and it was almost null for the inconclusive category (kappa=0.058). Considering only readers from laboratories with documented experience, the kappa value was higher (kappa=0.747; 95% CI, 0.643-0.839) compared with nonexperienced centers (kappa=0.498; 95% CI, 0.388-0.616). The results were similar in both sets of slides (kappa=0.505 [95% CI, 0.358-0.642] and kappa=0.521 [95% CI, 0.240-0.698] for the first and second sets, respectively). Reinterpretation of the slides with the most discordant results did not provide any improvement (first evaluation, kappa=0.616 [95% CI, 0.384-0.866]; second evaluation, kappa=0.403 [95% CI, 0.182-0.643]). CONCLUSIONS: Dual staining for p16(ink4a) and Ki-67 demonstrated good reproducibility, confirming its robustness, which is a necessary prerequisite for its adoption as a triage test in cervical cancer screening programs that use human papillomavirus DNA as a primary test. Cancer Cytopathol 2017; 125:212-20. (C) 2016 American Cancer Society
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