839 research outputs found
The Mercury Game: Evaluating a Negotiation Simulation that Teaches Students about Science–Policy Interactions
Environmental negotiations and policy decisions take place at the science–policy interface. While this is well known in academic literature, it is often difficult to convey how science and policy interact to students in environmental studies and sciences courses. We argue that negotiation simulations, as an experiential learning tool, are one effective way to teach students about how science and policy interact in decision-making. We developed a negotiation simulation, called the Mercury Game, based on the global mercury treaty negotiations. To evaluate the game, we conducted surveys before and after the game was played in university classrooms across North America. For science students, the simulation communicates
how politics and economics affect environmental negotiations. For environmental studies and policy students, the mercury simulation demonstrates how scientific uncertainty can affect decision-making. Using
the mercury game as an education tool allows students to learn about complex interactions between science and society and develop communication skills.This research was funded by the U.S. National Science Foundation (#1053648)
Correction:Did medical doctors who order abdominal CT scans during on-call hours truly become worse at clinical reasoning? Yes, they did
Correction:Did medical doctors who order abdominal CT scans during on-call hours truly become worse at clinical reasoning? Yes, they did
Novel approaches for analysing gut microbes and dietary polyphenols: challenges and opportunities
Polyphenols, ubiquitously present in the food we consume, may modify the gut microbial composition and/or activity, and moreover, may be converted by the colonic microbiota to bioactive compounds that influence host health. The polyphenol content of fruit and vegetables and derived products is implicated in some of the health benefits bestowed on eating fruit and vegetables. Elucidating the mechanisms behind polyphenol metabolism is an important step in understanding their health effects. Yet, this is no trivial assignment due to the diversity encountered in both polyphenols and the gut microbial composition, which is further confounded by the interactions with the host. Only a limited number of studies have investigated the impact of dietary polyphenols on the complex human gut microbiota and these were mainly focused on single polyphenol molecules and selected bacterial populations. Our knowledge of gut microbial genes and pathways for polyphenol bioconversion and interactions is poor. Application of specific in vitro or in vivo models mimicking the human gut environment is required to analyse these diverse interactions. A particular benefit can now be gained from next-generation analytical tools such as metagenomics and metatranscriptomics allowing a wider, more holistic approach to the analysis of polyphenol metabolism. Understanding the polyphenol gut microbiota interactions and gut microbial bioconversion capacity will facilitate studies on bioavailability of polyphenols in the host, provide more insight into the health effects of polyphenols and potentially open avenues for modulation of polyphenol bioactivity for host health
Protective Heterologous Antiviral Immunity and Enhanced Immunopathogenesis Mediated by Memory T Cell Populations
A basic principle of immunology is that prior immunity results in complete protection against a homologous agent. In this study, we show that memory T cells specific to unrelated viruses may alter the host's primary immune response to a second virus. Studies with a panel of heterologous viruses, including lymphocytic choriomeningitis (LCMV), Pichinde (PV), vaccinia (VV), and murine cytomegalo (MCMV) viruses showed that prior immunity with one of these viruses in many cases enhanced clearance of a second unrelated virus early in infection. Such protective immunity was common, but it depended on the virus sequence and was not necessarily reciprocal. Cell transfer studies showed that both CD4 and CD8 T cell populations from LCMV-immune mice were required to transfer protective immunity to naive hosts challenged with PV or VV. In the case of LCMV-immune versus naive mice challenged with VV, there was an enhanced early recruitment of memory phenotype interferon (IFN) γ–secreting CD4+ and CD8+ cells into the peritoneal cavity and increased IFN-γ levels in this initial site of virus replication. Studies with IFN-γ receptor knockout mice confirmed a role for IFN-γ in mediating the protective effect by LCMV-immune T cell populations when mice were challenged with VV but not PV. In some virus sequences memory cell populations, although clearing the challenge virus more rapidly, elicited enhanced IFN-γ–dependent immunopathogenesis in the form of acute fatty necrosis. These results indicate that how a host responds to an infectious agent is a function of its history of previous infections and their influence on the memory T cell pool
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