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Oceanic eddies accompanied by a significant vertical velocity ( w ) are known to be of great importance for the vertical transport of various climatically, biologically or biogeochemically relevant properties. Using quasi-geostrophic w -thinking to extend the classic “ β -spiral” w -theory for gyre circulations to isolated and nearly symmetric oceanic mesoscale eddies, we propose that their w motion will be dominated by a strong east-west dipole pattern with deep ocean penetrations. Contrasting numerical simulations of idealized isolated eddies together with w -equation diagnostics confirm that the w -dipole is indeed dominated by the “eddy β -spiral” mechanism in the β -plane simulation, whereas this w -dipole expectedly disappears in the f -plane simulation. Analyses of relatively isolated warm and cold eddy examples show good agreement with the proposed mechanism. Our studies further clarify eddy vertical motions, have implications for ocean mixing and vertical transport, and inspire further studies. 

ABSTRACT Iron–sulfur clusters are involved in many biological processes, including photosynthetic electron transport in the chloroplast and respiratory electron transport in the mitochondrion. Iron–sulfur cluster biosynthesis requires iron–sulfur carriers such as nitrogen‐fixation‐subunit‐U [NFU]‐type proteins. TheArabidopsis thaliananuclear genome encodes two mitochondrion‐targeted NFU proteins: NFU4 and NFU5, previously reported to have a primary role in the biosynthesis of the lipoate cofactor, mediated by the 4Fe–4S enzyme lipoyl synthase. Through in vitro reconstitution and spectroscopic analysis, we found that recombinant NFU4 and NFU5 proteins had UV–visible features characteristic of 4Fe–4S clusters. In addition, we confirmed that double homozygous, complete loss‐of‐functionnfu4 nfu5mutants had an embryo‐lethal phenotype. To investigate the functional relationship between NFU4 and NFU5, we generated sesquimutants that were homozygous loss‐of‐function for one gene and heterozygous for the other, which appeared slightly smaller thannfu4‐2,nfu4‐4, andnfu5‐1single mutants. This suggests that the simultaneous decrease in levels of NFU4 and NFU5 proteins may have an additive effect on plant growth. Quantitative reverse transcription PCR showed that theNFU4transcript was absent in mutants homozygous fornfu4‐2andnfu4‐4and that theNFU5transcript level was substantially reduced in thenfu5‐1single mutant or sesquimutants. Consistent with the transcript data, the abundances of NFU4 and NFU5 proteins were either virtually absent or substantially reduced in the corresponding single mutants and sesquimutants. Immunoblot analysis showed that mostnfu4andnfu5‐1single, double, and sesquimutants had significant reductions in the levels of mitochondrial 4Fe–4S proteins, such as aconitase (ACO) and biotin synthase 2 (BIO2; note that BIO2 also contains a 2Fe–2S cluster). In addition,nfu4 nfu5sesquimutants showed substantial reductions in the protein level of the 75‐kDa subunit of respiratory complex I (CI75), which contains one 2Fe–2S cluster and two 4Fe–4S clusters. These observations indicate that NFU4 and NFU5 are important in maintaining the levels of mitochondrial 4Fe–4S proteins. Such observations are also consistent with the hypothesis that NFU4 and NFU5 may serve as iron–sulfur carriers and may play a role in the transfer of 4Fe–4S clusters to recipient apoproteins, such as ACO and CI75, during the biogenesis and maturation of mitochondrial 4Fe–4S clusters. 

Global sea-level rise is transforming coastal ecosystems, especially freshwater wetlands, in part due to increased episodic or chronic saltwater exposure, leading to shifts in biogeochemistry, plant- and microbial communities, as well as ecological services. Yet, it is still difficult to predict how soil microbial communities respond to the saltwater exposure because of poorly understood microbial sensitivity within complex wetland soil microbial communities, as well as the high spatial and temporal heterogeneity of wetland soils and saltwater exposure. To address this, we first conducted a two-year survey of microbial community structure and bottom water chemistry in submerged surface soils from 14 wetland sites across the Florida Everglades. We identified ecosystem-specific microbial biomarker taxa primarily associated with variation in salinity. Bacterial, archaeal and fungal community composition differed between freshwater, mangrove, and marine seagrass meadow sites, irrespective of soil type or season. Especially, methanogens, putative denitrifying methanotrophs and sulfate reducers shifted in relative abundance and/or composition between wetland types. Methanogens and putative denitrifying methanotrophs declined in relative abundance from freshwater to marine wetlands, whereas sulfate reducers showed the opposite trend. A four-year experimental simulation of saltwater intrusion in a pristine freshwater site and a previously saltwater-impacted site corroborated the highest sensitivity and relative increase of sulfate reducers, as well as taxon-specific sensitivity of methanogens, in response to continuously pulsing of saltwater treatment. Collectively, these results suggest that besides increased salinity, saltwater-mediated increased sulfate availability leads to displacement of methanogens by sulfate reducers even at low or temporal salt exposure. These changes of microbial composition could affect organic matter degradation pathways in coastal freshwater wetlands exposed to sea-level rise, with potential consequences, such as loss of stored soil organic carbon. 

This study offers the first investigation on the normative processes through which Chinese form impressions of others in social interaction. Using affect control theory and its archived sentiment data from China, I estimate the Chinese impression formation models with a new Bayesian method. I then compare the Chinese models to the impression formation dynamics in U.S. English. Results show cross-cultural commonality in the affective processing of cultural concepts, with determinants of impression formation processes being largely universal. Findings also reveal two cultural variations that align with patterns uncovered by comparative cross-cultural research: 1) the Chinese models show less rigidity in the definition of situation; and 2) across two cultural models, the balance term has opposite effects on actor and behavior evaluation. To explore the implications of the impression models, I present a series of simulations, illustrating the predictive power of affect control theory as well as the impact of different cultural rules on social interaction. 

We review Affect Control Theory (ACT), a mathematically formalized theory that integrates sociological insights about the symbolic construction of the social order with psychological knowledge about cognitive-affective mechanisms, as a basis for equipping computational agents in social simulations with a sense of sociality. After explaining theoretical foundations and describing previous applications of ACT at the dyadic and group level, we describe a case study from an ongoing research project aimed at understanding self-organized online collaboration in software development with ACT-based social simulations. 

Comprehensive and accurate comparisons of transcriptomic distributions of cells from samples taken from two different biological states, such as healthy versus diseased individuals, are an emerging challenge in single-cell RNA sequencing (scRNA-seq) analysis. Current methods for detecting differentially abundant (DA) subpopulations between samples rely heavily on initial clustering of all cells in both samples. Often, this clustering step is inadequate since the DA subpopulations may not align with a clear cluster structure, and important differences between the two biological states can be missed. Here, we introduce DA-seq, a targeted approach for identifying DA subpopulations not restricted to clusters. DA-seq is a multiscale method that quantifies a local DA measure for each cell, which is computed from its k nearest neighboring cells across a range of k values. Based on this measure, DA-seq delineates contiguous significant DA subpopulations in the transcriptomic space. We apply DA-seq to several scRNA-seq datasets and highlight its improved ability to detect differences between distinct phenotypes in severe versus mildly ill COVID-19 patients, melanomas subjected to immune checkpoint therapy comparing responders to nonresponders, embryonic development at two time points, and young versus aging brain tissue. DA-seq enabled us to detect differences between these phenotypes. Importantly, we find that DA-seq not only recovers the DA cell types as discovered in the original studies but also reveals additional DA subpopulations that were not described before. Analysis of these subpopulations yields biological insights that would otherwise be undetected using conventional computational approaches. 

This paper explores how individuals' privacy-related decision-making processes may be influenced by their pre-existing relationships to companies in a wider social and economic context. Through an online role-playing exercise, we explore attitudes to a range of services including home automation, Internet-of-Things and financial services. We find that individuals do not only consider the privacy-related attributes of applications, devices or services in the abstract. Rather, their decisions are heavily influenced by their pre-existing perceptions of, and relationships with, the companies behind such apps, devices and services. In particular, perceptions about a company's size, level of regulatory scrutiny, relationships with third parties, and pre-existing data exposure lead some users to choose an option which might otherwise appear worse from a privacy perspective. This finding suggests a need for tools that support users to incorporate these existing perceptions and relationships into their privacy-related decision making.