PNAS nexus最新文献

Leveraging every undergraduate application submitted by self-identified Hispanic applicants to the University of California system in the 2016 and 2017 application cycles, we show that a significant number of applicants claim Hispanic identity by virtue of European heritage. We subsequently demonstrate that Hispanic-identifying students of European descent are significantly more affluent and more likely to apply to selective University of California campuses than their non-European Hispanic peers. We comment on the practical implications of these disparities, as well as their relevance for studies of inequality in the social sciences and education.

The sequencing of PCR amplicons is a core application of high-throughput sequencing technology. Using unique molecular identifiers (UMIs), individual amplified molecules can be sequenced to very high accuracy on an Illumina sequencer. However, Illumina sequencers have limited read length and are therefore restricted to sequencing amplicons shorter than 600 bp unless using inefficient synthetic long-read approaches. Native long-read sequencers from Pacific Biosciences and Oxford Nanopore Technologies can, using consensus read approaches, match or exceed Illumina quality while achieving much longer read lengths. Using a circularization-based concatemeric consensus sequencing approach (R2C2) paired with UMIs (R2C2 + UMI), we show that we can sequence an ∼550-nt antibody heavy chain (Immunoglobulin heavy chain - IGH) and an ∼1,500-nt 16S amplicons at accuracies up to and exceeding Q50 (<1 error in 100,000 sequenced bases), which exceeds accuracies of UMI-supported Illumina-paired sequencing as well as synthetic long-read approaches.

We develop an endogenous approach to the practice of denunciation, as an alternative to exogenous historical and sociological accounts. It analyzes denunciation as a response to increasing pressure, which in turn increases pressure on social contacts. The research context is the trial of Waldensians in Giaveno, Italy, in 1335, headed by the inquisitor Alberto de Castellario. A dynamic network actor model attests that coercive pressure not only raises the rate of denunciation but also compels denouncers to implicate individuals who are socially closer to them. We find that coercive pressure starts yielding diminishing returns relatively quickly, with the degree of redundancy of information escalating as a result of preferential attachment, increasingly targeting those already denounced by others, publicly announced suspects, and those having absconded from the trial.

Can foreign conflicts affect attitudes in nonbelligerent countries? A large literature studies the effects of conflicts and wars on countries that are directly involved, without considering the potential consequences for other nonbelligerent countries that might nevertheless be threatened. To address this question, we examine how the Russian invasion of Ukraine affected 12 economic and political attitudes using survey data covering eight European countries. We use a natural experiment whereby the timing of the invasion overlapped with the fieldwork of a cross-national individual-level survey in these eight countries. We find that the war increased support for democracy, redistribution, support for Europe, and immigration, while it reduced authoritarian attitudes. Our findings highlight the impact of foreign conflicts on a wide range of attitudes in countries that are externally threatened, but neither directly involved militarily, nor necessarily very close to the conflict.

Individuals who have more ambition-a persistent striving for success, attainment, and accomplishment-are more likely to become leaders. But are these ambitious individuals also more effective in leadership roles? We hypothesize that leader ambition is related to positive self-views of leader effectiveness that remain uncorroborated by relevant third-party actors. In a multiwave, preregistered study, we find evidence for this hypothesis using a sample of executives (N = 3,830 ratings of 472 leaders) who were rated by peers, subordinates, managers, and themselves on ten leadership competencies, including their ability to motivate others, manage collaborative work, coach and develop people, and present and communicate ideas. We consider the implications of our findings for both scholars and practitioners interested in leadership selection and development.

Many warn that the United States is on the brink of democratic collapse, because partisan animosity, support for partisan violence, and support for undemocratic practices are on the rise. Quelling some fears, scholars have offered interventions that use messages to correct misperceptions about citizens' partisan opponents (the "out-party"). In this article, we provide evidence that the effects of these interventions are not as robust or consistent as hoped. First, we use panel data ( $n=\mathrm{9,810}$ ) to show that perceptions of the out-party are highly variable. This suggests that these perceptions are weakly held and thus unlikely to be a significant cause of hostile attitudes. The oscillation of perceptions over time also suggests that, for many, any effect of corrections would likely be overwhelmed in just 1 month. Second, in a meta-analysis of 67 statistical tests from 12 studies in eight papers, we document that current evidence on the efficacy of corrections is weak. Third and finally, in pre-registered experiments ( $n=\mathrm{2,846}$ ), we find that changing Americans' perceptions of the out-party's demographics, policy attitudes, and support for undemocratic practices has no consistent effect on partisan animosity, support for partisan violence, or support for undemocratic practices. These observations suggest that correcting misperceptions of the out-party is not a panacea for our democratic ills.

Theorists have argued that morality builds on several core modular foundations. When do different moral foundations emerge in life? Prior work has explored the conceptual development of different aspects of morality in childhood. Here, we offer an alternative approach to investigate the developmental emergence of moral foundations through the lexicon, namely the words used to talk about moral foundations. We develop a large-scale longitudinal analysis of the linguistic mentions of five moral foundations (in both virtuous and vicious forms) in naturalistic speech between English-speaking children with ages ranging from 1 to 6 and their caretakers. Using computational methods, we collect a dataset of 1,371 human-annotated moral utterances and automatically annotate around one million utterances in child-caretaker conversations. We discover that in childhood, words for expressing the individualizing moral foundations (i.e. Care/Harm, Fairness/Cheating) tend to emerge earlier and more frequently than words for expressing the binding moral foundations (i.e. Authority/Subversion, Loyalty/Betrayal, Purity/Degradation), and words for Care/Harm are expressed substantially more often than the other foundations. We find significant differences between children and caretakers in how often they talk about Fairness, Cheating, and Degradation. Furthermore, we show that the information embedded in childhood speech allows computational models to predict moral judgment of novel scenarios beyond the scope of child-caretaker conversations. Our work provides a large-scale documentation of the moral foundational lexicon in early linguistic communication in English and forges a new link between moral language development and computational studies of morality.

Myc is a major driver of tumor initiation, progression, and maintenance. Up-regulation of Myc protein level rather than acquisition of neomorphic properties appears to underlie most Myc-driven cancers. Cellular mechanisms governing Myc expression remain incompletely defined. In this study, we show that ribosome-associated quality control (RQC) plays a critical role in maintaining Myc protein level. Ribosomes stall during the synthesis of the N-terminal portion of cMyc, generating aberrant cMyc species and necessitating deployment of the early RQC factor ZNF598 to handle translational stress and restore cMyc translation. ZNF598 expression is up-regulated in human glioblastoma (GBM), and its expression positively correlates with that of cMyc. ZNF598 knockdown inhibits human GBM neurosphere formation in cell culture and Myc-dependent tumor growth in vivo in Drosophila. Intriguingly, the SARS-COV-2-encoded translational regulator Nsp1 impinges on ZNF598 to restrain cMyc translation and consequently cMyc-dependent cancer growth. Remarkably, Nsp1 exhibits synthetic toxicity with the translation and RQC-related factor ATP-binding cassette subfamily E member 1, which, despite its normally positive correlation with cMyc in cancer cells, is co-opted by Nsp1 to down-regulate cMyc and inhibit tumor growth. Ribosome stalling during c-myc translation thus offers actionable cancer cell vulnerability.

Whether and how community structure variation affects plant sexual reproduction is crucial for understanding species' local adaptation and plant community assembly, but remains unrevealed. In Qinghai-Tibetan grassland communities that differed in aboveground biomass (AGB) and species diversity, we found significant influence of AGB on both species' reproductive biomass allocation (RBA) and flowering and fruiting time, but of species diversity only on species' reproductive time. In high-AGB or high-diversity communities, smaller and earlier flowering species generally advanced their reproductive phenology and increased their reproductive allocation for maximizing their reproductive success, whereas larger and later flowering species delayed their reproductive phenology and decreased their reproductive allocation for maximizing their vegetative growth and resource competition. This change in reproductive allocation with the variation in community structures was more pronounced in nonclonal as compared to clonal plant species. Thus, we evidence an important influence of community structure on plant sexual reproduction strategies, and the pattern of the influence depends largely on species biological attributes.

Behavioral nudges in Facebook ads reached nearly 15 million people across six diverse countries and, consequently, many thousands took the step of navigating to governments' vaccine signup sites. However, none of the treatment ads caused significantly more vaccine signup intent than placebo uniformly across all countries. Critically, reporting the descriptive norm that 87% of people worldwide had either been vaccinated or planned vaccination-social proof-did not meaningfully increase vaccine signup intent in any country and significantly backfired in Taiwan. This result contradicts prominent prior findings. A charge to "protect lives in your family" significantly outperformed placebo in Taiwan and Turkey but saw null effects elsewhere. A message noting that vaccination significantly reduces hospitalization risk decreased signup intent in Brazil and had no significant effects in any other country. Such heterogeneity was the hallmark of the study: some messages saw significant treatment effects in some countries but failed in others. No nudge outperformed the placebo in Russia, a location of high vaccine skepticism. In all, widely touted behavioral nudges often failed to promote vaccine signup intent and appear to be moderated by cultural context.