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Objective. Lead-doped scintillator dosimeters may be well suited for the dosimetry of FLASH-capable x-ray radiotherapy beams. Our study explores the dose rate dependence and temporal resolution of scintillators that makes them promising in the accurate detection of ultrahigh dose-rate (UHDR) x-rays. Approach. We investigated the response of scintillators with four material compositions to UHDR x-rays produced by a conventional x-ray tube. Scintillator output was measured using the HYPERSCINT-RP100 dosimetry research platform. Measurements were acquired at high frame rates (400 fps) which allowed for accurate dose measurements of sub-second radiation exposures from 1 to 100 ms. Dose-rate dependence was assessed by scaling tube current of the x-ray tube. Scintillator measurements were validated against Monte Carlo simulations of the probe geometries and UHDR x-ray system. Calibration factors converting dose-to-medium to dose-to-water were obtained from simulation data of plastic and lead-doped scintillator materials. Main Results. The results of this work suggest that lead-doped scintillators were dose-rate independent for UHDR x-rays from 1.1 to 40.1 Gy s -1 and capable of measuring conventional radiotherapy dose-rates (0.1 Gy s -1 ) at extended distance from the x-ray focal spot. Dose-to-water measured with a 5% lead-doped scintillator detector agreed with simulations within 0.6%. Significance. Lead-doped scintillators may be a valuable tool for the accurate real-time dosimetry of FLASH-capable UHDR x-ray beams., (Creative Commons Attribution license.)

Objectives: Medical management based on palliative chemotherapy is currently the standard of care in malignant pleural mesothelioma (MPM). Median survival of 12-16 months has been reported with modern chemotherapy regimens with or without anti-angiogenic agents. Multimodality therapy incorporating cytoreductive surgery, systemic chemotherapy and radiotherapy has been offered for years to fit patients with early-stage disease, but its role remains debated. Our objective was to compare overall survival in patients offered multimodality therapy in a specialized clinic setting in London, UK to that of patients offered exclusively medical treatment at another academic institution in Quebec, Canada., Materials and Methods: We retrospectively compared the survival rates of 2 separate cohorts of patients treated consecutively: Cohort 1 (n = 106) received multimodality therapy including systemic chemotherapy, extended pleurectomy/decortication (P/D) and prophylactic radiotherapy in London (United Kingdom) between 2009 and 2016, while Cohort 2 (n = 98) received medical treatment at the Quebec Heart and Lung Institute (Canada) during the same period., Results: In Cohort 1, all patients but two completed trimodality therapy. In cohort 2, 51 % received palliative care only and 40 % received systemic chemotherapy. Median survival was 32 months vs 10 months in Cohort 1 and Cohort 2, respectively (hazard ratio with age, gender, pathology and TNM staging as covariates: 3.81; 95 % CI: 2.67-5.45; p < 0.0001). Similar results were obtained in sensitivity analyses, after excluding those who received best supportive care only and in a propensity score-matched analysis., Conclusion: Aggressive therapy of MPM using cancer-directed surgery, systemic chemotherapy and prophylactic radiotherapy may provide a significant survival benefit in selected patients., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Goals: To describe the various dimensions of parental involvement in the interventions initiated in schools and to identify the relationship between each of these dimensions and the development of children's food choices following their exposure to a nutrition-education project implemented in eight primary schools in underprivileged neighbourhoods in Montréal - the Junior Cooks - Parents Network project (Petits cuistots - Parents en réseaux (PC-PR))., Method: This descriptive research was conducted thanks to a secondary analysis of data from a sample of 502 parents of children attending schools that participated in the PC-PR project. Parental participation is described in four aspects, making reference to the idea of a mesosystem, suggested by Bronfenbrenner (1979). Children's eating-related behaviour, as reported by the parents, included: talking about workshops, asking to buy certain foods, reading labels on product wrapping and helping to prepare the meal. Bivariate and multivariate descriptive analyses were performed., Results: The data gathered from the parents show a positive association between in-home parental involvement and overall food behaviour in the students. However, there is no association between parental involvement at school and any of the behaviours., Conclusion: This research suggests the importance of parental participation in nutrition education interventions in schools. The results contribute to the advancement of knowledge in the field and serve as impetus for reflection on how to better direct health promotion interventions.

In many species of cercopithecines female rank is inherited matrilineally so that maternal kin occupy adjacent ranks. A female is said to have acquired her matrilineal rank in relation to a given subordinate female when the submission she receives from that female and the aggression she directs to her are both unidirectional. Kin support appears to be important in that process (rank acquisition). Matrilineally dominant females also appear to need kin support for maintaining their rank once they have acquired it. This is inferred from observations indicating that subordinates can form kin-based coalitions and outrank single dominant females. Therefore, if subordinates did not, or could not, form coalitions, the maintenance of rank among similar-sized females might be independent of kin support. One test of this hypothesis would be to remove all kin support shortly after rank acquisition has taken place. We report such a test performed in a group of captive Macaca fuscata composed of three families with similar age-sex compositions. Experimental subgroups were formed by placing together peers from different families and a single kin (ally) of one subordinate peer (mother or older sister). These experiments induced a series of rank reversals whereby the subordinate peer, whose ally was present, outranked the dominant peers. Following the rank reversals, the ally of the newly dominant peer was removed and the peers left together. All five experimentally inverted rank orders of peers remained stable. The finding that experimentally subordinate individuals abstained from challenging experimentally dominant peers despite their long ontogenetic experience of reversed dominance roles suggests (1) that matrilineal rank acquisition is a punctuate (versus ontogenetically cumulative) process, (2) that the maintenance of rank among peers does not necessitate kin support if subordinates cannot form coalitions, and (3) that the "minimal risk constraint on competition" helps account for the stability of matrilineal hierarchies., (Copyright © 1988 Wiley‐Liss, Inc., A Wiley Company.)