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We propose a quantization of coarse spaces and uniform Roe algebras. The objects are based on the quantum relations introduced by N. Weaver and require the choice of a represented von Neumann algebra. In the case of the diagonal inclusion ell_infty(X) subset B(ell_2(X)), they reduce to the usual constructions. Quantum metric spaces furnish natural examples parallel to the classical setting, but we provide other examples that are not inspired by metric considerations, including the new class of support expansion C*-algebras. We also work out the basic theory for maps between quantum coarse spaces and their consequences for quantum uniform Roe algebras. 

ABSTRACT Microcystisspp. are renowned for producing the hepatotoxin microcystin in freshwater cyanobacterial harmful algal blooms around the world, threatening drinking water supplies and public and environmental health. However,Microcystisgenomes also harbor numerous biosynthetic gene clusters (BGCs) encoding the biosynthesis of other secondary metabolites, including many with toxic properties. Most of these BGCs are uncharacterized and currently lack links to biosynthesis products. However, recent field studies show that many of these BGCs are abundant and transcriptionally active in natural communities, suggesting potentially important yet unknown roles in bloom ecology and water quality. Here, we analyzed 21 xenicMicrocystiscultures isolated from western Lake Erie to investigate the diversity of the biosynthetic potential of this genus. Through metabologenomic andin silicoapproaches, we show that theseMicrocystisstrains contain variable BGCs, previously observed in natural populations, and encode distinct metabolomes across cultures. Additionally, we find that the majority of metabolites and gene clusters are uncharacterized, highlighting our limited understanding of the chemical repertoire ofMicrocystisspp. Due to the complex metabolomes observed in culture, which contain a wealth of diverse congeners as well as unknown metabolites, these results underscore the need to deeply explore and identify secondary metabolites produced byMicrocystisbeyond microcystins to assess their impacts on human and environmental health.IMPORTANCEThe genusMicrocystisforms dense cyanobacterial harmful algal blooms (cyanoHABs) and can produce the toxin microcystin, which has been responsible for drinking water crises around the world. While microcystins are of great concern,Microcystisalso produces an abundance of other secondary metabolites that may be of interest due to their potential for toxicity, ecological importance, or pharmaceutical applications. In this study, we combine genomic and metabolomic approaches to study the genes responsible for the biosynthesis of secondary metabolites as well as the chemical diversity of produced metabolites inMicrocystisstrains from the Western Lake Erie Culture Collection. This unique collection comprisesMicrocystisstrains that were directly isolated from western Lake Erie, which experiences substantial cyanoHAB events annually and has had negative impacts on drinking water, tourism, and industry. 

Abstract Occupational choices at the early stage of one's career path are influenced by the real and imagined input of mentors. This research focuses on PhD advisors and the graduate students that they mentor. Each participant in that dyadic mentoring relationship holds assumptions about the beliefs of the other regarding the students' career preferences. We propose that, in the absence of discussions surrounding career goals in such relationships, pluralistic ignorance surrounding career norms may develop. PhD students may assume that their advisors prefer that students seek academic research positions; while advisors may assume students prefer academic research positions and may not bring up alternative careers. Three studies adopt a mixed‐method approach to investigate divergent experiences surrounding career discussions. Study 1A (N = 301 faculty members in STEM fields) features qualitative and quantitative data and found that PhD advisors have experience working with students whose career preferences did not align with their expectations, and report changing their mentorship approaches while maintaining rigorous training. Study 1B (N = 195 PhD students in STEM fields) features qualitative data and found that students, although generally comfortable discussing different career options with their advisors, report several concerns that deterred them from discussing nonacademic research positions. Study 2, an experiment designed to compare perceived with actual norms (N = 200 PhD students in STEM fields) revealed that such discomfort could be alleviated by making explicit advisors' support for diverse career options and actual career preferences. The present research provides insights about pluralistic ignorance with implications for having more holistic career discussions in dyadic mentor relationships. 

The widespread threat of contagious disease disrupts not only everyday life but also psychological experience. Building on findings regarding xenophobic responses to contagious diseases, this research investigates how perceived vulnerability to a disease moderates the psychological link between people’s xenophobic thoughts and support for ingroup-protective actions. Three datasets collected during the time of Ebola ( N = 867) and COVID-19 ( Ns = 992 and 926) measured perceived disease risk, group-serving biases (i.e., xenophobic thoughts), and support for restrictive travel policies (i.e., ingroup-protective actions). Using correlational and quasi-experimental analyses, results indicated that for people who perceive greater disease risk, the association between group-serving bias and restrictive policy support is weakened. This weakened association occurred because people who felt more vulnerable to these diseases increased support for ingroup-protective actions more strongly than xenophobic thoughts. This research underscores the importance of understanding the impact of threats on psychological processes beyond the impact on psychological outcomes. 

Differences in national responses to COVID-19 have been associated with the cultural value of collectivism. The present research builds on these findings by examining the relationship between collectivism at the individual level and adherence to public health recommendations to combat COVID-19 during the pre-vaccination stage of the pandemic, and examines different characteristics of collectivism (i.e., concern for community, trust in institutions, perceived social norms) as potential psychological mechanisms that could explain greater compliance. A study with a cross-section of American participants (N= 530) examined the relationship between collectivism and opting-in to digital contact tracing (DCT) and wearing face coverings in the general population. More collectivistic individuals were more likely to comply with public health interventions than less collectivistic individuals. While collectivism was positively associated with the three potential psychological mechanisms, only perceived social norms about the proportion of people performing the public health interventions explained the relationship between collectivism and compliance with both public health interventions. This research identifies specific pathways by which collectivism can lead to compliance with community-benefiting public health behaviors to combat contagious diseases and highlights the role of cultural orientation in shaping individuals’ decisions that involve a tension between individual cost and community benefit. 

ABSTRACT The Winam Gulf in the Kenyan region of Lake Victoria experiences prolific, year-round cyanobacterial harmful algal blooms (cyanoHABs) which pose threats to human, livestock, and ecosystem health. To our knowledge, there is limited molecular research on the gulf’s cyanoHABs, and thus, the strategies employed for survival and proliferation by toxigenic cyanobacteria in this region remain largely unexplored. Here, we used metagenomics to analyze the Winam Gulf’s cyanobacterial composition, function, and biosynthetic potential.Dolichospermumwas the dominant bloom-forming cyanobacterium, co-occurring withMicrocystisat most sites.MicrocystisandPlanktothrixwere more abundant in shallow and turbid sites. Metagenome-assembled genomes (MAGs) ofDolichospermumharbored nitrogen fixation genes, suggesting diazotrophy as a potential mechanism supporting the proliferation ofDolichospermumin the nitrogen-limited gulf. Over 300 biosynthetic gene clusters (BGCs) putatively encoding the synthesis of toxins and other secondary metabolites were identified across the gulf, even at sites where there were no visible cyanoHAB events. Almost all BGCs identified had no known synthesis product, indicating a diverse and novel biosynthetic repertoire capable of synthesizing harmful or potentially therapeutic metabolites.MicrocystisMAGs containedmcygenes encoding the synthesis of hepatotoxic microcystins which are a concern for drinking water safety. These findings illustrate the spatial variation of bloom-forming cyanobacteria in the Winam Gulf and their available strategies to dominate different ecological niches. This study underscores the need for further use of genomic techniques to elucidate the dynamics and mitigate the potentially harmful effects of cyanoHABs and their associated toxins on human, environmental, and economic health.