The hypothesis that zooplankton display local adaptations to toxic cyanobacteria was tested by investigating the performance of 24 clones from six populations of the large-bodied Daphnia pulex and 13 clones from four populations of the small-bodied Chydorus sphaericus. They were fed a pure nutritious green alga Chlorella pyrenoidosa (good food) and a mixed diet with a toxic cyanobacterium Microcystis aeruginosa (poor food). The grazer performances feeding on the poor food significantly differed among their populations over a small geographic scale (7-10 km for D. pulex and 15-20 km for C. sphaericus). Both the absolute tolerance (performance on poor food) and relative tolerance (performance on poor food relative to good food) to toxic M. aeruginosa were enhanced with increasing microcystin concentrations in the sediments and finally reached the maximum values. Additionally, the significant food 3 clone interactions indicated that phenotypic plasticity in response to toxic cyanobacteria had a genetic basis in two grazers. The significant food 3 population interactions and correlations between growth plasticity and microcystin concentrations indicated that this phenotypic plasticity evolved across grazer populations. The reduced plasticity was evidenced by both the reduced slope of reaction norms and the enhanced mean performance for both diets. D. pulex had more evolutionary potential for the reduced plasticity than C. sphaericus. These results suggest that zooplankton populations developed evolutionary tolerance to toxic cyanobacteria on a microgeographic level.

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The new coronavirus makes the world recognize that all nations share the same future in the era of globalization. Global cooperation, especially scientific collaboration, is the key to accelerate understanding of the COVID-19 virus and the fight against the pandemic. By visualizing the research cooperation network on COVID-19 as of April 15, 2020, we found that cities and institutes in China played an important role in promoting COVID-19 research cooperation.

Prion disease is a group of transmissible neurodegenerative disorders affecting humans and animals. The prion hypothesis postulates that PrPSc, the pathogenic conformer of host-encoded prion protein (PrP), is the unconventional proteinaceous infectious agent called prion. Supporting this hypothesis, highly infectious prion has been generated in vitro with recombinant PrP plus defined non-protein cofactors and the synthetically generated prion (recPrPSc) is capable of causing prion disease in wild-type mice through intracerebral (i.c.) or intraperitoneal (i.p.) inoculation. Given that many of the naturally occurring prion diseases are acquired through oral route, demonstrating the capability of recPrPSc to cause prion disease via oral transmission is important, but has never been proven. Here we showed for the first time that oral ingestion of recPrPSc is sufficient to cause prion disease in wild-type mice, which was supported by the development of fatal neurodegeneration in exposed mice, biochemical and histopathological analyses of diseased brains, and second round transmission. Our results demonstrate the oral transmissibility of recPrPSc and provide the missing evidence to support that the in vitro generated recPrPSc recapitulates all the important properties of naturally occurring prions.

Accurately and objectively simulating the dynamic evolution of the behaviors of different decision-makers (DMs) is essential for identifying solutions to transboundary water conflicts. This research proposes an improved Graph Model for Conflict Resolution (GMCR) based on the benefits of DMs' behaviors to model the dynamic evolution of transboundary water conflicts. Additionally, the influence of third-party intervention on conflicts is investigated in depth. A demonstration area in the Yangtze River Delta on ecologically friendly development (DAYRD) in China is taken as the case study area. The results indicate that the improved GMCR model based on the benefit function can not only clearly identify the dynamic evolution path of transboundary water conflicts into cooperation, but also effectively avoid the