| 1. |
- Palmerini, Giovanni B., et al.
(författare)
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Design of debris removal missions performed by robotic graspers
- 2012
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Ingår i: 63rd International Astronautical Congress 2012. - Paris : International Astronautical Federation. - 9781622769797 ; , s. 6356-6366
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Konferensbidrag (refereegranskat)abstract
- The well known increase of the orbiting debris, leading to a critical condition in which additional launches could be precluded, calls for mitigation and removal practices. First, and maybe easier to accomplish with respect to other concepts under study, some missions should be probably carried out in a close fiiture to grasp large unused orbiting objects, like upper stages or idle spacecraft that already ended their operational lifetime. The focus on large objects, even if they are a limited subset of orbiting spent bodies, helps in two ways: The reduction of the cross section for possible impacts, and, more remarkably, the reduction of the number and size of additional debris to be generated in a possible collision. As a result, these targets can justify the cost and the complexity of removal missions which, even if almost traditional in the approach and not-too-far from current operational capabilities, still pose significant technical problems. The paper aims to present the operational sequence of a removal mission to be performed by a robotic spacecraft. The issues relevant for the different phases are discussed, with a special focus on the grasping operations, when the robotic arms of the servicing spacecraft, after the determination of the relative kinematic state of the target, should carcfully embraces and precisely catch, in a safe area, the orbiting body. Such an approach should bypass obstacles like solar panels and avoid the break-up of the target, possibly degraded due to its long exposure to space environment. The results of simulations under reasonable, engineering hypothesis for the mission's scenario are presented, with the estimate of torques and forces to be exerted by the robotic arms. The attitude issues for the servicing spacecraft, as well as the vibration behaviour for an accurate end-effector positioning during robotic arms manoeuvres are considered. The confidence in the findings of these numerical studies is strengthened by the know-how gained with the related experimental activities performed during recent years in the labs at Sapienza Universita' di Roma by means of dedicated, small test-beds
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| 2. |
- Sousa-Pinto, Bernardo, et al.
(författare)
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Comparison of rhinitis treatments using MASK-air® data and considering the minimal important difference
- 2022
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Ingår i: Allergy. European Journal of Allergy and Clinical Immunology. - : John Wiley & Sons. - 0105-4538 .- 1398-9995. ; 77:10, s. 3002-3014
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Tidskriftsartikel (refereegranskat)abstract
- Background: Different treatments exist for allergic rhinitis (AR), including pharmacotherapy and allergen immunotherapy (AIT), but they have not been compared using direct patient data (i.e., “real-world data”). We aimed to compare AR pharmacological treatments on (i) daily symptoms, (ii) frequency of use in co-medication, (iii) visual analogue scales (VASs) on allergy symptom control considering the minimal important difference (MID) and (iv) the effect of AIT.Methods: We assessed the MASK-air® app data (May 2015–December 2020) by users self-reporting AR (16–90 years). We compared eight AR medication schemes on reported VAS of allergy symptoms, clustering data by the patient and controlling for confounding factors. We compared (i) allergy symptoms between patients with and without AIT and (ii) different drug classes used in co-medication.Results: We analysed 269,837 days from 10,860 users. Most days (52.7%) involved medication use. Median VAS levels were significantly higher in co-medication than in monotherapy (including the fixed combination azelastine-fluticasone) schemes. In adjusted models, azelastine-fluticasone was associated with lower average VAS global allergy symptoms than all other medication schemes, while the contrary was observed for oral corticosteroids. AIT was associated with a decrease in allergy symptoms in some medication schemes. A difference larger than the MID compared to no treatment was observed for oral steroids. Azelastine-fluticasone was the drug class with the lowest chance of being used in co-medication (adjusted OR = 0.75; 95% CI = 0.71–0.80).Conclusion: Median VAS levels were higher in co-medication than in monotherapy. Patients with more severe symptoms report a higher treatment, which is currently not reflected in guidelines.
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| 3. |
- Sousa-Pinto, Bernardo, et al.
(författare)
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Consistent trajectories of rhinitis control and treatment in 16,177 weeks : the MASK-air® longitudinal study
- 2023
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Ingår i: Allergy. European Journal of Allergy and Clinical Immunology. - : John Wiley & Sons. - 0105-4538 .- 1398-9995. ; 78:4, s. 968-983
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Data from mHealth apps can provide valuable information on rhinitis control and treatment patterns. However, in MASK-air®, these data have only been analyzed cross-sectionally, without considering the changes of symptoms over time. We analyzed data from MASK-air® longitudinally, clustering weeks according to reported rhinitis symptoms. Methods: We analyzed MASK-air® data, assessing the weeks for which patients had answered a rhinitis daily questionnaire on all 7 days. We firstly used k-means clustering algorithms for longitudinal data to define clusters of weeks according to the trajectories of reported daily rhinitis symptoms. Clustering was applied separately for weeks when medication was reported or not. We compared obtained clusters on symptoms and rhinitis medication patterns. We then used the latent class mixture model to assess the robustness of results. Results: We analyzed 113,239 days (16,177 complete weeks) from 2590 patients (mean age ± SD = 39.1 ± 13.7 years). The first clustering algorithm identified ten clusters among weeks with medication use: seven with low variability in rhinitis control during the week and three with highly-variable control. Clusters with poorly-controlled rhinitis displayed a higher frequency of rhinitis co-medication, a more frequent change of medication schemes and more pronounced seasonal patterns. Six clusters were identified in weeks when no rhinitis medication was used, displaying similar control patterns. The second clustering method provided similar results. Moreover, patients displayed consistent levels of rhinitis control, reporting several weeks with similar levels of control. Conclusions: We identified 16 patterns of weekly rhinitis control. Co-medication and medication change schemes were common in uncontrolled weeks, reinforcing the hypothesis that patients treat themselves according to their symptoms.
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