Abstract Besides the local effects of ionizing radiation at the cellular and molecular levels in tumor tissues, the interactions of radiotherapy with the host’s immune system are nowadays at the ...center of many investigations. In some cases, these interactions can be strong enough to immunize the patient against the tumor, leading to a rejection by the host of both the irradiated tumor and distant metastases. In this latter case, the rejection mechanism is called “abscopal effect”. Over the last two decades, increasing attention has also been paid to the combination of various forms of immunotherapies with radiation, as an attempt to boost cancer cell killing mechanisms. In particular, a significant number of translational and clinical studies are now investigating both the effects of immune checkpoint blockade strategies and adoptive immunotherapies in combination with radiation. A better understanding of the mechanisms driving the interactions between ionizing radiation and the immune system help us envision the advantages that may be offered by the adjunction of immunotherapy to radiotherapy in various clinical models.
We introduce some general tools to design exact splitting methods to compute numerically semigroups generated by inhomogeneous quadratic differential operators. More precisely, we factorize these ...semigroups as products of semigroups that can be approximated efficiently, using, for example, pseudo-spectral methods. We highlight the efficiency of these new methods on the examples of the magnetic linear Schrödinger equations with quadratic potentials, some transport equations and some Fokker–Planck equations.
This review article deals with bank erosion from the perspective of rivers affected by seasonal ice formation. These rivers drain half of the terrestrial land surface globally, and are mainly located ...in both periglacial and cold, non-periglacial environments across the Northern Hemisphere. This review is based on a literature survey of 126 publications (articles, technical reports, conference papers and book chapters) documenting case studies in temperate and polar climates. The first section details the global issues of bank erosion and pinpoints concerns specific to northern environments. The second section describes the dominant erosion processes (fluvial vs. terrestrial), mechanisms (mechanical vs. thermal) and typical landforms encountered in the literature. The third section reviews the environmental factors (hydraulic vs. non-hydraulic) controlling bank erosion, with a focus on the different forms of river ice. The fourth section deals with the spatial and temporal variability in bank-erosion processes, discussing the distribution of process dominance occurring at the reach scale and the catchment scale, and describing the temporal window in which each process dominates. The fifth section reviews the expected impacts on bank erosion resulting from climate-induced disturbances on hydrological cycles and from increasing anthropogenic pressures along riverbanks in northern countries. The relationships among erosion processes, environmental factors, climate change, and human impacts are summarized in a sixth section that introduces a new synthetic conceptual diagram of bank erosion. Research needs that should be investigated in the future are highlighted in the seventh section while the final section synthesizes all the aspects presented in this review.
Field‐acclimatised spruce budworm larvae, Choristoneura fumiferana, supercool to as low as −41.6°C in winter months. Yet the extent to which they can withstand exposures to temperatures slightly ...above their supercooling point has never been investigated. In both January and February 2018, we tested various combinations of sub‐zero temperatures (−37 to −42°C) and exposure durations (0.75–12 h) to estimate the combinations of temperature and exposure durations required to kill half the population (LTT50). At −37 or −38°C, the estimated emergence probability was about 0.80 at all exposure durations. In contrast, the LTT50 was reached after 11.4 h at −39°C, 9.4 h at −40°C, and 3 h at −41°C. A temperature of −42°C was fatal to most larvae.
During the winters of 2017, 2018 and 2019, survival experiments were conducted at three latitudes (46–48°N) in Québec. Regardless of the year or latitude, none of the daily minimum temperatures recorded in January or February were cold enough to reach the LTT50. However, the sudden drops in temperature that occurred after the winter thaw of March and in early December 2018 were likely responsible for the low proportions of emerged larvae observed.
Hence, despite the high capacity of spruce budworm larvae to withstand very low sub‐zero temperatures in winter months, they remain highly vulnerable to cold spells during their early diapause or post‐diapause development. Such climatic disturbances deserve more attention, as they may increase under climate change.
Choristoneura fumiferana overwinters as diapausing second‐instar larvae inside a silk hibernaculum spun on coniferous trees, with larvae supercooling to as low as −41.6°C in both January and February.
At least 50% of larvae died after ˂ 12 h of exposure to temperatures ranging from −39 to −42°C (LTT50 curve). In contrast, even after 12 h of exposure to −37 or −38°C, >50% of larvae successfully emerged.
Despite their high degree of cold‐hardiness, C. fumiferana larvae remain vulnerable to cold spells throughout the winter.
Jesuit accounts of the colonial Americas Donato, Clorinda; Lüsebrink, Hans-Jürgen; Bernier, Marc André
Jesuit accounts of the colonial Americas,
2014., 20140814, 2014, 2014-08-14
eBook
Linking Jesuit texts, the rhetorical tradition, and the newly emerging anthropology of the Enlightenment, this collection traverses the vast expanses of Old and New World France and Spain in ...fascinating new ways.
Explore knowledge on resilience-promoting interventions among adolescents receiving active cancer treatment. The question used to guide the research was: How can nurses promote resilience among ...adolescents receiving active cancer treatment?
Adolescence is a very turbulent stage of development (Young, 2014). A cancer diagnosis at this age contributes to emotional distress and reduces quality of life (Sodergren et al., 2017). However, some youth develop positive coping mechanisms that lead to increased resilience (Bellizzi et al., 2012; Sodergren et al., 2017). Because nurses often care for these patients over an extended period of time, they can play an important role in fostering this resilience.
Three databases (CINAHL, PubMed and PsycArticles) were consulted in February 2023, using research limiters "2013-2023" and "adolescents" (teenagers) both in French and in English. Potentially relevant sources were selected based on the guidelines identified by Pollock et al., (2021). Data were extracted, analyzed and presented using the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews checklist (Tricco et al., 2018). The results were categorized, using deductive reasoning, as either protective factors or risk factors, in line with the Resilience in Illness Model (RIM; (Haase et al., 2014, 2017). Finally, potential interventions were identified where nurses can foster resilience among adolescents actively undergoing cancer treatment.
The method used returned 86 studies, 17 of which met the selection criteria. Of these, 10 were quantitative in nature, three were qualitative, three were theoretical (including literature reviews and meta-analyses) and one was an editorial. The majority (n = 15) were published in the United States. There have been no studies specifically examining the role of nurses in promoting resilience among adolescents undergoing active cancer treatment since 2013.
Based on the findings of this paper, considering that information has been published on the role nurses serve in caring for adolescents who have a chronic illness other than cancer, the conclusion is that pediatric oncology nurses can be key players in promoting resilience among patients at this stage of development. Studies focusing specifically on this topic would be useful in determining how to facilitate adaptation and foster resilience effectively among adolescents receiving active cancer treatment.
Bisphenol A (BPA) is an endocrine disrupting chemical used in a wide range of consumer products including photoactive dyes used in thermal paper. Recent studies have shown that dermal absorption of ...BPA can occur when handling these papers. Yet, regulatory agencies have largely dismissed thermal paper as a major source of BPA exposure. Exposure estimates provided by agencies such as the European Food Safety Authority (EFSA) are based on assumptions about how humans interact with this material, stating that 'typical' exposures for adults involve only one handling per day for short periods of time (<1 minute), with limited exposure surfaces (three fingertips). The objective of this study was to determine how individuals handle thermal paper in one common setting: a cafeteria providing short-order meals. We observed thermal paper handling in a college-aged population (n = 698 subjects) at the University of Massachusetts' dining facility. We find that in this setting, individuals handle receipts for an average of 11.5 min, that >30% of individuals hold thermal paper with more than three fingertips, and >60% allow the paper to touch their palm. Only 11% of the participants we observed were consistent with the EFSA model for time of contact and dermal surface area. Mathematical modeling based on handling times we measured and previously published transfer coefficients, concentrations of BPA in paper, and absorption factors indicate the most conservative estimated intake from handling thermal paper in this population is 51.1 ng/kg/day, similar to EFSA's estimates of 59 ng/kg/day from dermal exposures. Less conservative estimates, using published data on concentrations in thermal paper and transfer rates to skin, indicate that exposures are likely significantly higher. Based on our observational data, we propose that the current models for estimating dermal BPA exposures are not consistent with normal human behavior and should be reevaluated.
The frequency of forest fires is predicted to increase in Canada, which may affect the availability of timber for industrial purposes. We therefore carried out an evaluation of the timber supply ...vulnerability to current and future fire risk through simplified calculations involving historical forest growth and harvest rates and current and projected forest burn rates. Calculations were performed at the level of forest management areas (FMAs) across the boreal and montane ecozones of Canada. For some FMAs, the vulnerability of timber supply to fire was estimated to be high to extreme by the middle of the century. For those FMAs, the increases in tree growth necessary to negate these risks were generally unrealistic. A modest simulated decrease in tree growth over time, however, was sufficient to raise the vulnerability of many other FMAs from low to moderate. Known biases in the analysis suggest that our assessment might underestimate the level of vulnerability in all FMAs. Other natural disturbances are not included in the analysis but their impact on timber supply may be additive to that of fire. Some adaptation measures to face these increasing risks are discussed.
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