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Autonomous systems often operate in environments where state feedback may not be available, such as in anti-access and area denial environments. In these environments, it is often required that an agent track a path, despite interruptions in state feedback. As a result, the class of Relay-Explorer problems has emerged, where a switched system approach is used to account for intermittent state feedback. Past work on these problems established a framework for developing dwell-time conditions for stable tracking using these methods. However, existing work only applies to a limited class of reference paths and feedback region geometries. This letter advances a topologically inspired method for guaranteeing re-acquisition of feedback for nearly arbitrary geometries in arbitrary dimensions, all while relaxing the dwell-time conditions and retaining the uniformly ultimately bounded stability result from preceding work. Numerical experiments in the plane demonstrate an increase of hundreds of percentage points—even for fairly generic geometries—in the tracking error the agent could afford, using the proposed method, without sacrificing stability.

Summary Background Hydroxychloroquine is one of several agents being evaluated in the treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We aimed to examine whether patients with rheumatological conditions receiving chronic hydroxychloroquine therapy are at less risk of developing SARS-CoV-2 infection than those not receiving hydroxychloroquine. Methods This retrospective cohort study included de-identified information of all veterans in the US Veterans Health Administration clinical administrative database aged 18 years or older with rheumatoid arthritis, systemic lupus erythematosus, or associated rheumatological conditions (based on International Classification of Diseases, 10th edition, diagnostic codes) who were alive on March 1, 2020. A propensity score was calculated for each patient, and each patient who was receiving hydroxychloroquine was matched to two patients who were not receiving hydroxychloroquine (controls). The primary endpoint was the proportion of patients with PCR-confirmed SARS-CoV-2 infection among those receiving chronic hydroxychloroquine versus the propensity-matched patients not receiving chronic hydroxychloroquine between March 1 and June 30, 2020. Secondary outcomes were hospital admission associated with SARS-CoV-2 infection; intensive care requirement associated with SARS-CoV-2 infection; mortality associated with SARS-CoV-2 infection; and overall rates of any hospital admission and mortality (ie, all cause). Multivariate logistic regression analysis was done to determine independent variables for the development of active SARS-CoV-2 infection. Findings Between March 1 and June 30, 2020, 10 703 patients receiving hydroxychloroquine and 21 406 patients not receiving hydroxychloroquine were included in the primary analysis. The incidence of active SARS-CoV-2 infections during the study period did not differ between patients receiving hydroxychloroquine and patients not receiving hydroxychloroquine (31 [0·3%] of 10 703 vs 78 [0·4%] of 21 406; odds ratio 0·79, 95% CI 0·52–1·20, p=0·27). There were no significant differences in secondary outcomes between the two groups in patients who developed active SARS-CoV-2 infection. For all patients in the study, overall mortality was lower in the hydroxychloroquine group than in the group of patients who did not receive hydroxychloroquine (odds ratio 0·70, 95% CI 0·55–0·89, p=0·0031). In multivariate logistic regression analysis, receipt of hydroxychloroquine was not associated with the development of active SARS-CoV-2 infection (odds ratio 0·79, 95% CI 0·51–1·42). Interpretation Hydroxychloroquine was not associated with a preventive effect against SARS-CoV-2 infection in a large group of patients with rheumatological conditions. Funding None.

Building on unpublished ethnography conducted in Massachusetts, 2011–2014, this chapter compares and contrasts context-specific notions and practices of ‘solidarity’ among collaborative networks that are active in organizing alternative forms of food procurement. The terms of comparison is Grasseni’s (Beyond alternative food networks: Italy’s solidarity purchase groups. London: Bloomsbury, 2013) ethnography of Italian Gruppi di Acquisto Solidale, or Solidarity Purchase Groups in northern Italy. Recent ethnographic examples from Italy – concerning especially cooperatives – are contrasted with the US solidarity economy network in the context of the Boston local food movement and Massachusetts community-supported agriculture. The chapter unravels and juxtapose different conceptions, discourse and relevant practices of solidarity in collaborative networks that self-define as ‘solidarity economy networks’ or as ‘solidarity and green economy’ alliances, in order to show how context-bound the meaning of solidarity in collective food procurement is. By showing how ‘solidarity’ translates into different local solutions and social movements, the chapter highlights the sociocultural dimensions of these local experiments in food system transformations.

International audience; Numerous measurements of fission product yields were performed since the discovery of the nuclear fission process. However, more precise and reliable fission product yields are requested. Lack of covariance matrices make difficult to use it for specific application purposes such as the propagation uncertainty of decay heat. In this work, we propose to measure independently the fission product mass yields for the whole heavy peak (including the symmetric mass region) for the $^{233}$U$(\text {n}_{\text {th}},\text {f})$ reaction. Both average values and experimental covariance is provided. The fission product mass yields are measured with the LOHENGRIN recoil mass spectrometer of the ILL using an ionization chamber located at the focal plane. A new procedure of data taking has been developed in order to minimize the biases. Concretely several ionic charges and kinetic energy distributions have been measured for each mass. Particular attention has been considered in the monitoring of the target time evolution. Additional corrections were necessary in the symmetry mass region due to contaminants coming from the LOHENGRIN recoil mass spectrometer. A complex Monte Carlo analysis has been developed in order to better propagate all the uncertainties. The fission product mass yields of the $^{233}$U$(\text {n}_{\text {th}},\text {f})$ and its associated covariance matrix has been produced. An overall good agreement has been observed with ENDF/B-VIII.0 in contrast with the JEFF-3.3 evaluation. A precision around 2% for the heavy peak has been measured. The experimental covariance matrix was also computed. In the symmetry mass region, two components were observed in the kinetic energy distribution. One of this component was considered as an artifact and was ruled-out.

During an experimental campaign performed at the LOHENGRIN recoil spectrometer of the Institut Laue-Langevin (ILL), a kinetic energy dependence of 132Sn fission product isomeric ratio (IR) has been measured by inducing thermal fission of 241Pu. The IRs are deduced using gamma ray spectrometry in coincidence with the ionisation chamber. To interpret these data, we use the FIFRELIN Monte-Carlo code to simulate the de-excitation of the fission fragments. Combining the IRs with the FIFRELIN calculations, the angular momentum distribution with kinetic energy of the doubly magic nucleus of 132Sn was deduced. This will be compared with the angular momentum distribution obtained for the reaction 235U(nth,f) for 132Sn.

Introduction The European medical information framework (EMIF) was an Innovative Medicines Initiative project jointly supported by the European Union and the European Federation of Pharmaceutical Industries and Associations, that generated a common technology and governance framework to identify, assess and (re)use healthcare data, to facilitate real‐world data research. The objectives of EMIF included providing a unified platform to support a wide range of studies within two verification programmes—Alzheimer's disease (EMIF‐AD), and metabolic consequences of obesity (EMIF‐MET). Methods The EMIF platform was built around two main data‐types: electronic health record data and research cohort data, and the platform architecture composed of a set of tools designed to enable data discovery and characterisation. This included the EMIF catalogue, which allowed users to find relevant data sources, including the data‐types collected. Data harmonisation via a common data model were central to the project especially for population data sources. EMIF also developed an ethical code of practice to ensure data protection, patient confidentiality and compliance with the European Data Protection Directive, and GDPR. Results Currently 18 population‐based disease agnostic and 60 cohort‐based Alzheimer's data partners from across 14 countries are contained within the catalogue, and this will continue to expand. The work conducted in EMIF‐AD and EMIF‐MET includes standardizing cohorts, summarising baseline characteristics of patients, developing diagnostic algorithms, epidemiological studies, identifying and validating novel biomarkers and selecting potential patient samples for pharmacological intervention. Conclusions EMIF was designed to provide a sustainable model as demonstrated by the sustainability plans for EMIF‐AD. Although network‐wide studies using EMIF were not conducted during this project to evaluate its sustainability, learning from EMIF will be used in the follow‐on IMI‐2 project, European Health Data and Evidence Network (EHDEN). Furthermore, EMIF has facilitated collaborations between partners and continues to promote a wider adoption of principles, technology and architecture through some of its continued work.