PNAS Nexus Pub Date : 2024-09-18 DOI: 10.1093/pnasnexus/pgae402

Fabiola Ramelli, Jan Henneberger, Christopher Fuchs, Anna J Miller, Nadja Omanovic, Robert Spirig, Huiying Zhang, Robert O David, Kevin Ohneiser, Patric Seifert, Ulrike Lohmann

{"title":"Repurposing weather modification for cloud research showcased by ice crystal growth","authors":"Fabiola Ramelli, Jan Henneberger, Christopher Fuchs, Anna J Miller, Nadja Omanovic, Robert Spirig, Huiying Zhang, Robert O David, Kevin Ohneiser, Patric Seifert, Ulrike Lohmann","doi":"10.1093/pnasnexus/pgae402","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgae402","url":null,"abstract":"The representation of cloud processes in models is one of the largest sources of uncertainty in weather forecast and climate projections. While laboratory settings offer controlled conditions for studying cloud processes, they cannot reproduce the full range of conditions and interactions present in natural cloud systems. To bridge this gap, here we leverage weather modification, specifically glaciogenic cloud seeding, to investigate ice growth rates within natural clouds. Seeding experiments were conducted in supercooled stratus clouds (at −8 to −5 °C) using an uncrewed aerial vehicle, and the created ice crystals were measured 4-10 min downwind by in situ and ground-based remote sensing instrumentation. We observed substantial variability in ice crystal growth rates within natural clouds, attributed to variations in ice crystal number concentrations and in the supersaturation, which is difficult to reproduce in the laboratory and which implies faster precipitation initiation than previously thought. We found that for the experiments conducted at −5.2 °C, the ice crystal populations grew nearly linearly during the time interval from 6 to 10 minutes. Our results demonstrate that the targeted use of weather modification techniques can be employed for fundamental cloud research (e.g., ice growth processes, aerosol-cloud interactions), helping to advance cloud microphysics parameterizations and to improve weather forecasts and climate projections.","PeriodicalId":516525,"journal":{"name":"PNAS Nexus","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An integrated experiment-modeling approach to identify key processes for carbon mineralization in fractured mafic and ultramafic rocks. 采用实验-模型综合方法确定裂隙岩浆岩和超基性岩中碳矿化的关键过程。

PNAS Nexus Pub Date : 2024-09-18 DOI: 10.1093/pnasnexus/pgae388

Chelsea W Neil, Yun Yang, Haylea Nisbet, Uwaila C Iyare, Lawrence O Boampong, Wenfeng Li, Qinjun Kang, Jeffrey D Hyman, Hari S Viswanathan

{"title":"An integrated experiment-modeling approach to identify key processes for carbon mineralization in fractured mafic and ultramafic rocks.","authors":"Chelsea W Neil, Yun Yang, Haylea Nisbet, Uwaila C Iyare, Lawrence O Boampong, Wenfeng Li, Qinjun Kang, Jeffrey D Hyman, Hari S Viswanathan","doi":"10.1093/pnasnexus/pgae388","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgae388","url":null,"abstract":"Controlling atmospheric warming requires immediate reduction of carbon dioxide (CO2) emissions, as well as the active removal and sequestration of CO2 from current point sources. One promising proposed strategy to reduce atmospheric CO2 levels is geologic carbon sequestration (GCS), where CO2 is injected into the subsurface and reacts with the formation to precipitate carbonate minerals. Rapid mineralization has recently been reported for field tests in mafic and ultramafic rocks. However, unlike saline aquifers and depleted oil and gas reservoirs historically considered for GCS, these formations can have extremely low porosities and permeabilities, limiting storage volumes and reactive mineral surfaces to the pre-existing fracture network. As a result, coupling between geochemical interactions and the fracture network evolution is a critical component of long-term, sustainable carbon storage. In this paper, we summarize recent advances in integrating experimental and modeling approaches to determine the first order processes for carbon mineralization in a fractured mafic/ultramafic rock system. We observe the critical role of fracture aperture, flow, and surface characteristics in controlling the quantity, identity, and morphology of secondary precipitates and present where the influence of these factors can be reflected in newly developed thermo-hydro-mechanical-chemical models. Our findings provide a roadmap for future work on carbon mineralization, as we present the most important system components and key challenges that we are overcoming to enable GCS in mafic and ultramafic rocks.","PeriodicalId":516525,"journal":{"name":"PNAS Nexus","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cultural bias and cultural alignment of large language models 大型语言模型的文化偏差和文化调整

PNAS Nexus Pub Date : 2024-09-17 DOI: 10.1093/pnasnexus/pgae346

Yan Tao, Olga Viberg, Ryan S Baker, René F Kizilcec

引用次数: 0

National politics ignites more talk of morality and power than local politics 与地方政治相比，国家政治引发了更多关于道德和权力的讨论

PNAS Nexus Pub Date : 2024-09-17 DOI: 10.1093/pnasnexus/pgae345

Danica Dillion, Curtis Puryear, Longjiao Li, Andre Chiquito, Kurt Gray

引用次数: 0

Leveraging body-worn camera footage to assess the effects of training on officer communication during traffic stops 利用随身摄像头录像评估培训对警官在交通拦截过程中沟通的影响

PNAS Nexus Pub Date : 2024-09-17 DOI: 10.1093/pnasnexus/pgae359

Nicholas P Camp, Rob Voigt, MarYam G Hamedani, Dan Jurafsky, Jennifer L Eberhardt

{"title":"Leveraging body-worn camera footage to assess the effects of training on officer communication during traffic stops","authors":"Nicholas P Camp, Rob Voigt, MarYam G Hamedani, Dan Jurafsky, Jennifer L Eberhardt","doi":"10.1093/pnasnexus/pgae359","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgae359","url":null,"abstract":"Can training police officers on how to best interact with the public actually improve their interactions with community members? This has been a challenging question to answer. Interpersonal aspects of policing are consequential but largely invisible in administrative records commonly used for evaluation. In this study, we offer a solution: body-worn camera footage captures police–community interactions and how they might change as a function of training. Using this footage-as-data approach, we consider changes in officers’ communication following procedural justice training in Oakland, CA, USA, one module of which sought to increase officer-communicated respect during traffic stops. We applied natural language processing tools and expert annotations of traffic stop recordings to detect whether officers enacted the five behaviors recommended in this module. Compared with recordings of stops that occurred prior to the training, we find that officers employed more of these techniques in posttraining stops; officers were more likely to express concern for drivers’ safety, offer reassurance, and provide explicit reasons for the stop. These methods demonstrate the promise of a footage-as-data approach to capture and affect change in police–community interactions.","PeriodicalId":516525,"journal":{"name":"PNAS Nexus","volume":"186 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Socioeconomic resources in youth are linked to divergent patterns of network integration/segregation across the brain’s transmodal axis 青少年的社会经济资源与大脑跨模态轴网络整合/隔离的不同模式有关

PNAS Nexus Pub Date : 2024-09-17 DOI: 10.1093/pnasnexus/pgae412

Cleanthis Michael, Aman Taxali, Mike Angstadt, Omid Kardan, Alexander Weigard, M Fiona Molloy, Katherine L McCurry, Luke W Hyde, Mary M Heitzeg, Chandra Sripada

{"title":"Socioeconomic resources in youth are linked to divergent patterns of network integration/segregation across the brain’s transmodal axis","authors":"Cleanthis Michael, Aman Taxali, Mike Angstadt, Omid Kardan, Alexander Weigard, M Fiona Molloy, Katherine L McCurry, Luke W Hyde, Mary M Heitzeg, Chandra Sripada","doi":"10.1093/pnasnexus/pgae412","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgae412","url":null,"abstract":"Socioeconomic resources (SER) calibrate the developing brain to the current context, which can confer or attenuate risk for psychopathology across the lifespan. Recent multivariate work indicates that SER levels powerfully relate to intrinsic functional connectivity patterns across the entire brain. Nevertheless, the neuroscientific meaning of these widespread neural differences remains poorly understood, despite its translational promise for early risk identification, targeted intervention, and policy reform. In the present study, we leverage graph theory to precisely characterize multivariate and univariate associations between SER across household and neighborhood contexts and the intrinsic functional architecture of brain regions in 5,821 youth (9-10 years) from the Adolescent Brain Cognitive Development StudySM. First, we establish that decomposing the brain into profiles of integration and segregation captures more than half of the multivariate association between SER and functional connectivity with greater parsimony (100-fold reduction in number of features) and interpretability. Second, we show that the topological effects of SER are not uniform across the brain; rather, higher SER levels are associated with greater integration of somatomotor and subcortical systems, but greater segregation of default mode, orbitofrontal, and cerebellar systems. Finally, we demonstrate that topological associations with SER are spatially patterned along the unimodal-transmodal gradient of brain organization. These findings provide critical interpretive context for the established and widespread associations between SER and brain organization. This study highlights both higher-order and somatomotor networks that are differentially implicated in environmental stress, disadvantage, and opportunity in youth.","PeriodicalId":516525,"journal":{"name":"PNAS Nexus","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142268388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Selective insensitivity to income held by the richest 对最富有者的收入不敏感

PNAS Nexus Pub Date : 2024-09-17 DOI: 10.1093/pnasnexus/pgae333

Barnabas Szaszi, Hooman Habibnia, Josephine Tan, Oliver P Hauser, Jon M Jachimowicz

{"title":"Selective insensitivity to income held by the richest","authors":"Barnabas Szaszi, Hooman Habibnia, Josephine Tan, Oliver P Hauser, Jon M Jachimowicz","doi":"10.1093/pnasnexus/pgae333","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgae333","url":null,"abstract":"The misperception of income inequality is often touted as a critical barrier to more widespread support of redistributive policies. Here, we examine to what extent and why (mis)perceptions vary systematically across the income distribution. Drawing on data from four studies (N = 2,744)—including a representative sample and preregistered incentive-compatible experiments—we offer converging evidence that people specifically underestimate the amount of income held by the top of the income distribution. While this selective underestimation is likely driven by multiple mechanisms, including systemic factors, we find that cognitive biases contribute to the observed pattern of results. The rise of inequality in many developed countries has been documented before, and the fact that this growing inequality is largely driven by the outsized gains of the richest individuals may pose new challenges previously underappreciated: our theory and findings highlight that cognitive biases pose a key obstacle to people's recognition of the concentration of income among the richest individuals, and may potentially distort their preferences for redistribution. We conclude by discussing future directions for research and the importance of incorporating behavioral and cognitive limitations into the design of redistributive public policy.","PeriodicalId":516525,"journal":{"name":"PNAS Nexus","volume":"113 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Confidence and second-order errors in cortical circuits 皮层电路中的置信度和二阶误差

PNAS Nexus Pub Date : 2024-09-14 DOI: 10.1093/pnasnexus/pgae404

Arno Granier, Mihai A Petrovici, Walter Senn, Katharina A Wilmes

{"title":"Confidence and second-order errors in cortical circuits","authors":"Arno Granier, Mihai A Petrovici, Walter Senn, Katharina A Wilmes","doi":"10.1093/pnasnexus/pgae404","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgae404","url":null,"abstract":"Minimization of cortical prediction errors has been considered a key computational goal of the cerebral cortex underlying perception, action and learning. However, it is still unclear how the cortex should form and use information about uncertainty in this process. Here, we formally derive neural dynamics that minimize prediction errors under the assumption that cortical areas must not only predict the activity in other areas and sensory streams but also jointly project their confidence (inverse expected uncertainty) in their predictions. In the resulting neuronal dynamics, the integration of bottom-up and top-down cortical streams is dynamically modulated based on confidence in accordance with the Bayesian principle. Moreover, the theory predicts the existence of cortical second-order errors, comparing confidence and actual performance. These errors are propagated through the cortical hierarchy alongside classical prediction errors and are used to learn the weights of synapses responsible for formulating confidence. We propose a detailed mapping of the theory to cortical circuitry, discuss entailed functional interpretations and provide potential directions for experimental work.","PeriodicalId":516525,"journal":{"name":"PNAS Nexus","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The origin and function of arbitrary signals: Making false statements, having long hair, and smoking Virginia Slims 任意信号的起源和功能：说假话、留长发和吸弗吉尼亚细条烟

PNAS Nexus Pub Date : 2024-09-14 DOI: 10.1093/pnasnexus/pgae408

Birger Wernerfelt

{"title":"The origin and function of arbitrary signals: Making false statements, having long hair, and smoking Virginia Slims","authors":"Birger Wernerfelt","doi":"10.1093/pnasnexus/pgae408","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgae408","url":null,"abstract":"We propose a model in which players take actions that run counter to social norms in part to announce their stand on a social controversy but also, and maybe mostly, to gain image benefits that allow them to join groups that are socially attractive to them. We give several examples, but the “election denial” debate is an important application: Rather than assuming that proponents believe their claims to be true, it suggests that false statements can serve as symbolic actions and help them engage in self-branding for social and psychological gain. Specifically, the willingness to make a controversial statement can be a credible signal because untruth is ill-received by some members of society and therefore entails some costs. It is immaterial whether election deniers believe their claim to be true, but it is important that some members of society believe that it is false and therefore think poorly of those who make it: If there is social consensus about the truth of a statement, it cannot serve a signaling function. The same mechanism explains several other verbal and non-verbal signals associated with different sides of social controversies and analysis of those helps clarify the mechanism.","PeriodicalId":516525,"journal":{"name":"PNAS Nexus","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Natural diversifying evolution of nonribosomal peptide synthetases in a defensive symbiont reveals nonmodular functional constraints 防御性共生体中非核糖体肽合成酶的自然多样化进化揭示了非模块化功能限制

PNAS Nexus Pub Date : 2024-09-13 DOI: 10.1093/pnasnexus/pgae384

Zhiyuan Li, Laura P Ióca, Ruolin He, Mohamed S Donia

{"title":"Natural diversifying evolution of nonribosomal peptide synthetases in a defensive symbiont reveals nonmodular functional constraints","authors":"Zhiyuan Li, Laura P Ióca, Ruolin He, Mohamed S Donia","doi":"10.1093/pnasnexus/pgae384","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgae384","url":null,"abstract":"The modular architecture of nonribosomal peptide synthetases (NRPSs) has inspired efforts to study their evolution and engineering. Here, we analyze in detail a unique family of NRPSs from the defensive intracellular bacterial symbiont, Candidatus Endobryopsis kahalalidifaciens. We show that intensive and indiscriminate recombination events erase trivial sequence covariations induced by phylogenetic relatedness, revealing nonmodular functional constraints and clear recombination units. Moreover, we reveal unique substrate specificity determinants for multiple enzymatic domains, allowing us to accurately predict and experimentally discover the products of an orphan NRPS in Ca. E. kahalalidifaciens directly from environmental samples of its algal host. Finally, we expanded our analysis to 1531 diverse NRPS pathways and revealed similar functional constraints to those observed in Ca. E. kahalalidifaciens’ NRPSs. Our findings reveal the sequence bases of genetic exchange, functional constraints, and substrate specificity in Ca. E. kahalalidifaciens’ NRPSs, and highlight them as a uniquely primed system for diversifying evolution.","PeriodicalId":516525,"journal":{"name":"PNAS Nexus","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

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