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Oxygen reductase origin followed the great oxidation event and terminated the Lomagundi excursion
No full textThe history of Earth's atmospheric oxygen is a cornerstone of evolutionary biology. While unequivocal evidence for an increase in atmospheric O2 marks the Great Oxidation Event (GOE) roughly 2.4 billion years ago, evidence underlying proposals for pre-GOE O2 accumulation is debated. Here we have investigated the distribution of genes for oxygen reductases, the enzymes that consume O2 in respiratory chains, across independently generated molecular timescales of prokaryotic evolution. The data indicate that cytochrome bd -oxidases, heme-copper oxidases and alternative oxidases arose in the wake of the GOE ca. 2.4 billion years ago, after which the genes were subjected to abundant lateral gene transfer, a reflection of their utility in redox balance and membrane bioenergetics. The data lead us to propose a straightforward four-stage model for O2 accumulation surrounding the GOE: (i) Negligible O2 existed prior to the GOE. (ii) Cyanobacterial O2 production started at the GOE, yet was capped at 2 % [ v /v] atmospheric O2, the threshold at which cyanobacterial nitrogenase is inhibited by O2. (iii) Production of 0.02 atm of O2 (2 % [ v /v]) at the GOE buried roughly the entire atmospheric CO2 inventory, causing sudden enrichment of 13C in dissolved inorganic carbon (the Lomagundi 13C anomaly), through RuBisCO isotope discrimination, without atmospheric O2 exceeding 2 % [ v /v]. (iv) High atmospheric 12C at the end of the Lomagundi excursion marks the origin of oxygen reductases, their rapid spread via function in respiratory CO2 liberation, and the onset of equilibrium between photosynthetic O2 production and respiratory O2 consumption at 2 % atmospheric O2
A Theory of Price Caps on Non-Renewable Resources
No full textWhat is the optimal response of a resource exporter when a price cap is imposed on
its main export? This paper develops a dynamic framework incorporating stochastic
prices, financial frictions, and market power to study this novel tool of statecraft. With
the right design, a price cap can incentivize increased extraction, stabilizing prices in
the global market. But the stabilizing effects diminish when there is leakage outside the
cap. Consequently, weak enforcement of the policy worsens the trade-off faced by the
sanctioning policymaker. We provide a systematic approach to setting and enforcing
an optimal cap level in these circumstances
Empowerment and individualization: Online banking and household financial organization
No full textBringing economic and family sociology into the digital era, this study examines and highlights the transformative potential of online banking in reconfiguring household financial organization. Using an instrumental-variable approach to analyzing data from the UK Household Longitudinal Study (2019–2023), we examine the impact of partners’ online banking use on who manages the couple’s money and controls major financial decisions. We reveal an ‘empowering effect’ whereby one’s use of online banking bolsters their control of both money management and major financial decisions, and this effect is particularly pronounced when one’s partner does not use online banking. Online banking similarly bolsters the power of women and men in money management, but subtle gender differences are observed in financial decision-making. Whereas online banking increases men’s exclusive control of major financial decisions, it bolsters women’s exclusive or joint control of such decisions. We also find an ‘individualizing effect’ whereby both women’s and men’s use of online banking increases the likelihood of partners’ independent money management, and independent money management is least likely when only one partner uses online banking. Our study provides novel insights into how digitalization, seen through online banking, redistributes power in and reconfigures the nature of couple relationships
Bioenergetics and lipid metabolism in Alzheimer's disease: From cell biology to systemic health
No full textAlzheimer's disease (AD) is a complex neurodegenerative disorder characterized by progressive cognitive decline. Although amyloid-β and tau pathologies remain central to our understanding of AD, growing evidence suggests that disrupted lipid metabolism and impaired bioenergetics are closely linked to these hallmark features. Genetic, lipidomic and functional studies point to alterations in cholesterol, phospholipids and polyunsaturated fatty acids, which can influence mitochondrial function, organelle communication and glial responses. These processes are further modulated by apolipoprotein E (APOE) genotype, sex differences and systemic metabolic states such as obesity and diabetes, contributing to neuroinflammation and cognitive decline. Although findings are sometimes conflicting, an emerging theme is that lipid and energy metabolisms are central to how genetic and environmental risk factors shape AD pathogenesis. This integrated perspective highlights lipid and bioenergetic pathways as promising therapeutic targets, where metabolic modulators, lipid-directed interventions and lifestyle strategies may complement amyloid-based therapies and offer opportunities for precision approaches, particularly in women and APOE ε4 carriers
Peruvian Peasant Women and Revolutionary Movements: La Convención’s Classist Revolution
No full textThis article examines the crucial yet underexplored role of indigenous peasant women in the struggle for agrarian reform and peasant liberation during the second half of the twentieth century in Latin America. Focusing on and re-examining the peasant movement of La Convención (Peru) and employing historical and anthropological methods, it argues that these women were far from peripheral actors. They actively engaged in unions, collective actions and even armed militias, performing both traditional and non-traditional gender roles to challenge the exploitative hacienda system and gender hierarchies. The article also analyses the impact of the Cold War on their rhetoric, alliances and broader struggle for social justice
Foreword: The State of the Field of Terracotta Architectural Decoration in ix Central Italy
No full textCultural differences in autonomy, social contacts, and sensory function for depression: A cross-national network analysis of older adults in England and South Korea
No full textPurpose: The links between autonomy, social contacts, sensory function, and depressive symptoms in older adults remains underexplored, particularly cross-culturally. This study examined their longitudinal associations in England and South Korea. / /
Method: Data were obtained from 4590 participants in the English Longitudinal Study of Ageing (ELSA) and 3803 participants in the Korean Longitudinal Study of Ageing (KLoSA), aged 65 and older, across three waves (2014/2015 to 2018/2019). Depressive symptoms were measured using eight CES-D items. Autonomy, social contacts, and sensory function were assessed through instrumental activities of daily living (IADL), frequency of social contact, and subjective vision and hearing. Temporal and contemporaneous network structures were analyzed using graphical vector autoregression modelling by gender and country. / /
Results: Impaired IADLs were stronger predictors of depressive symptoms in English men than Korean men (0.20 vs. 0.05). For Koreans, particularly women, social contact and depressive symptoms were mutually predictive (social contact→depressive symptoms: 0.12; depressive symptoms→social contact: 0.07). In English men, vision impairment predicted impaired IADLs (0.07), which then predicted depressive symptoms. In Koreans, hearing impairment predicted low social contacts (0.08), further influencing depressive symptoms. Out-strength centrality showed that IADLs were most influential for English men, while social contact was most influential for Korean men and for women in both countries. Sensory function showed cultural differences, with hearing more influential in Korea, vision in England. / /
Conclusions: Depression prevention strategies should account for cultural and gender differences, with autonomy more central in individualist contexts and social contact in collectivist ones
Perceptions of academic leaders in low- and middle-income countries about the role of WFME in enhancing the quality of medical education
No full textDespite the significant proportion of medical schools located in low- and middle-income countries (LMICs), little is known about how educational leaders in these contexts perceive various roles of the World Federation for Medical Education (WFME) and its connection with the Educational Commission for Foreign Medical Graduates (ECFMG). This article aims to explore how the role of WFME is perceived by medical educators and accrediting body members in LMICs, including WFME Standards for Basic Medical Education (SBME), the recognition programme, and the challenges and motivations in adopting SBME and seeking WFME recognition. This qualitative study employed semi-structured interviews with ten senior medical educationalists and members of national accreditation bodies from Pakistan, Sri Lanka, the Philippines, and Indonesia. Thematic analysis was conducted using an inductive approach to identify key themes regarding perceptions of WFME as an organization, its recognition programme, and its standards. Eleven themes emerged from the analysis, the most prominent of which was a considerable conceptual uncertainty about WFME’s role and authority among participants. The relationship between WFME and ECFMG was frequently misunderstood, with recognition often viewed primarily as a mechanism to facilitate graduate mobility rather than to improve educational quality. While WFME standards were perceived as sufficiently broad to allow contextual adaptation, participants identified significant challenges including resource constraints and political pressures when implementing standards and pursuing recognition. This study demonstrates that the pursuit of WFME recognition by accreditation agencies in LMICs appears to be driven more by external pressures than by conviction about its intrinsic value for quality improvement. Greater clarity about WFME’s role, improved communication about the recognition process, and more explicit attention to the needs and contexts of LMICs could enhance the relevance and impact of these global medical education initiatives
Eulerian–Lagrangian simulations of shear thinning and shear thickening in suspensions of repulsive particles
No full textDiscovery of disrupted sustained attention and altered functional connectivity in far-from-onset Huntington's disease gene-expanded young adults
No full textBACKGROUND:
Cognitive impairments are a hallmark of Huntington's disease (HD).
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METHODS:
Seventy-one participants (43 HD gene-expanded [HDGE], 28 healthy controls) from the HD-Young Adult Study at two timepoints ≈ 4.7 years apart, completed the Cambridge Neuropsychological Test Automated Battery Rapid Visual Information Processing task and underwent resting-state functional magnetic resonance imaging. We focused on predefined regions of interest that are involved in sustained attention.
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RESULTS:
HDGE individuals showed significantly poorer sustained attention than controls (padj = 0.007), with no significant change over time. Functional connectivity (FC) analyses revealed group differences in attention-related networks, including the occipital–operculum and lentiform–orbitalis pathways. Time and group × time effects were also observed in frontal and parietal regions.
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DISCUSSION:
These findings demonstrate early and persistent attention deficits in HDGE, linked to altered FC in attention-related circuits. This supports the presence of early cognitive dysfunction in HD and highlights potential compensatory and pathological changes in brain networks prior to the onset of clinical motor symptoms.
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Highlights:
We detail the discovery of early sustained attention deficits in Huntington's disease (HD) gene-expanded (HDGE) young adults.
These sustained attention deficits do not measurably decline over a 4.7-year period.
Altered functional connectivity was observed in attention-related brain networks.
Alterations in regions include occipital, opercular, lentiform, and frontal areas.
Findings support attention as an early cognitive biomarker in HDGE young adults