PNAS nexus最新文献_第7页

Epigenetic biomarkers of socioeconomic status are associated with age-related chronic diseases and mortality in older adults. 社会经济地位的表观遗传生物标志物与老年人年龄相关的慢性疾病和死亡率相关。

IF 2.2

PNAS nexus Pub Date : 2025-04-16 eCollection Date: 2025-04-01 DOI: 10.1093/pnasnexus/pgaf121

Lauren L Schmitz, Lauren A Opsasnick, Scott M Ratliff, Jessica D Faul, Wei Zhao, Timothy M Hughes, Jingzhong Ding, Yongmei Liu, Jennifer A Smith

{"title":"Epigenetic biomarkers of socioeconomic status are associated with age-related chronic diseases and mortality in older adults.","authors":"Lauren L Schmitz, Lauren A Opsasnick, Scott M Ratliff, Jessica D Faul, Wei Zhao, Timothy M Hughes, Jingzhong Ding, Yongmei Liu, Jennifer A Smith","doi":"10.1093/pnasnexus/pgaf121","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgaf121","url":null,"abstract":"Later-life health is patterned by socioeconomic influences across the lifecourse. However, the pathways underlying the biological embedding of socioeconomic status (SES) and its consequences on downstream morbidity and mortality are not fully understood. Epigenetic markers like DNA methylation (DNAm) may be promising surrogates of underlying biological processes that can enhance our understanding of how SES shapes population health. Studies have shown that SES is associated with epigenetic aging measures, but few have examined relationships between early and later-life SES and DNAm sites across the epigenome. In this study, we trained and tested DNAm-based surrogates, or \"biomarkers,\" of childhood and adult SES in two large, multiracial/ethnic samples of older adults-the Health and Retirement Study (n = 3,527) and the Multi-Ethnic Study of Atherosclerosis (n = 1,182). Both biomarkers were associated with downstream morbidity and mortality, and these associations persisted after controlling for measured SES, and in some cases, epigenetic aging clocks. Both childhood and adult SES biomarker CpG sites were enriched for genomic features that regulate gene expression (e.g. DNAse hypersensitivity sites and enhancers) and were implicated in prior epigenome-wide studies of inflammation, aging, and chronic disease. Distinct patterns also emerged between childhood CpGs and immune system dysregulation and adult CpGs and metabolic functioning, health behaviors, and cancer. Results suggest DNAm-based surrogate biomarkers of SES may be useful proxies for unmeasured social exposures that can augment our understanding of the biological mechanisms between social disadvantage and downstream health.","PeriodicalId":74468,"journal":{"name":"PNAS nexus","volume":"4 4","pages":"pgaf121"},"PeriodicalIF":2.2,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12041747/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144009035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Wearable face mask-attached disposable printed sensor arrays for point-of-need monitoring of alkaline gases in breath. 可穿戴式面罩附一次性印刷传感器阵列，用于呼吸中碱性气体的定点监测。

IF 2.2

PNAS nexus Pub Date : 2025-04-15 eCollection Date: 2025-04-01 DOI: 10.1093/pnasnexus/pgaf116

Giandrin Barandun, Abdulkadir Sanli, Chun Lin Yap, Alexander Silva Pinto Collins, Max Grell, Michael Kasimatis, Jeremy B Levy, Firat Güder

{"title":"Wearable face mask-attached disposable printed sensor arrays for point-of-need monitoring of alkaline gases in breath.","authors":"Giandrin Barandun, Abdulkadir Sanli, Chun Lin Yap, Alexander Silva Pinto Collins, Max Grell, Michael Kasimatis, Jeremy B Levy, Firat Güder","doi":"10.1093/pnasnexus/pgaf116","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgaf116","url":null,"abstract":"Blood sampling, despite its historical significance in clinical diagnostics, poses challenges, such as invasiveness, infection risks, and limited temporal fidelity for continuous monitoring. In contrast, exhaled breath offers a noninvasive, pain-free, and continuous sampling method, carrying biochemical information through volatile compounds like ammonia (NH3). NH3 in exhaled breath, influenced by kidney function, emerges as a promising biomarker for renal health assessment, particularly in resource-limited settings lacking extensive healthcare infrastructure. Current analytical methods for breath NH3, though effective, often face practical limitations. In this work, we introduce a low-cost, internet-connected, paper-based wearable device for measuring exhaled NH3, designed for early detection of kidney dysfunction at the point of need. The device, which attaches to disposable face masks, utilizes an array of disposable paper-based sensors to detect NH3 with the readout being changes in electrical impedance that correlate with the concentration of NH3. The sensor array is housed in a biodegradable plastic enclosure to mitigate high relative humidity issues in breath analysis. We validated our technology using a laboratory setup and human subjects who consumed ammonium chloride-containing candy to simulate elevated breath NH3. Our wearable sensor offers a promising solution for rapid, point-of-need kidney dysfunction screening, particularly valuable in resource-limited settings. This approach has potential applications beyond kidney health monitoring, including chemical industry safety and environmental sensing, paving the way for accessible, continuous health monitoring.","PeriodicalId":74468,"journal":{"name":"PNAS nexus","volume":"4 4","pages":"pgaf116"},"PeriodicalIF":2.2,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12038690/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144058185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Speciation with gene flow in an island endemic hummingbird. 岛屿特有蜂鸟的物种形成与基因流动。

IF 2.2

PNAS nexus Pub Date : 2025-04-15 eCollection Date: 2025-04-01 DOI: 10.1093/pnasnexus/pgaf095

Caroline Duffie Judy, Gary R Graves, John E McCormack, Katherine Faust Stryjewski, Robb T Brumfield

{"title":"Speciation with gene flow in an island endemic hummingbird.","authors":"Caroline Duffie Judy, Gary R Graves, John E McCormack, Katherine Faust Stryjewski, Robb T Brumfield","doi":"10.1093/pnasnexus/pgaf095","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgaf095","url":null,"abstract":"We examined speciation in streamertail hummingbirds (Trochilus polytmus and Trochilus scitulus), Jamaican endemic taxa that challenge the rule that bird speciation cannot progress in situ on small islands. Our analysis shows that divergent selection acting on male bill color, a sexual ornament that is red in polytmus and black in scitulus, acts as a key reproductive barrier. We conducted a population-level analysis of genomic and phenotypic patterns to determine the traits that contribute the most to speciation despite ongoing gene flow across a narrow hybrid zone. We characterized genomic patterns using 6,451 single-nucleotide polymorphisms and a segment of the mitochondrial control region. Our analyses revealed high diversity within species, and low divergence between them, consistent with a recent speciation event or extensive gene flow following secondary contact. We observed narrow clines in two phenotypic traits and several SNP loci. The cline width for male bill color is only 2.3 km, marking it as one of the narrowest phenotypic clines documented in an avian hybrid zone. The coincidence of estimated cline centers with the Rio Grande Valley suggests that this landscape feature may contribute to hybrid zone stability. However, given that streamertails are highly mobile, it is unlikely that such a narrow river acts as a physical barrier to dispersal. The limited genomic divergence across scanned regions of the genome offers little support for postmating reproductive barriers. Instead, our findings point to strong premating selection acting on bill color as the primary driver of streamertail speciation.","PeriodicalId":74468,"journal":{"name":"PNAS nexus","volume":"4 4","pages":"pgaf095"},"PeriodicalIF":2.2,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11997969/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144030916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Preserving coastal environments requires an integrated natural and cultural resources management approach. 保护沿海环境需要一种综合的自然和文化资源管理办法。

IF 2.2

PNAS nexus Pub Date : 2025-04-15 eCollection Date: 2025-04-01 DOI: 10.1093/pnasnexus/pgaf090

Jayur Madhusudan Mehta, Elizabeth L Chamberlain, Matthew Helmer, Elizabeth Haire, Mark D McCoy, Roy van Beek, Haizhong Wang, Siyu Yu

{"title":"Preserving coastal environments requires an integrated natural and cultural resources management approach.","authors":"Jayur Madhusudan Mehta, Elizabeth L Chamberlain, Matthew Helmer, Elizabeth Haire, Mark D McCoy, Roy van Beek, Haizhong Wang, Siyu Yu","doi":"10.1093/pnasnexus/pgaf090","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgaf090","url":null,"abstract":"Integration of natural and cultural resource management is urgently needed to combat the effects of climate change. Scientists must contend with how human-induced climate change and rapid population expansion are fundamentally reworking densely inhabited coastal zones. We propose that a merger of archaeology, environmental science, and land management policy-different yet intertwined domains-is needed to address dramatic losses to biocultural resources that comprise coupled cultural-natural systems. We demonstrate the urgency of such approaches through analyses of coastal archaeological regions within the U.S. Atlantic and Gulf coasts where sea level rise is a primary threat, and we extend our findings globally through an assessment of primary risk factors and forecasts for archaeological sites in the Netherlands, Peru, and Oceania. Results show that across the U.S. Gulf Coast and in Oceania, where little hard infrastructure is in place to protect archaeological sites, hundreds of low-lying coastal sites will be lost under future climate scenarios. In other coasts, like that of the Rhine-Meuse Delta (the Netherlands), risks range from erosion caused by periods of flooding to the degradation of wetland sites caused by extreme droughts. In coastal Peru, population pressures pose the primary risk to archaeological sites through rapid agro-industrial growth, urban expansion, and El Niño climate variability. Across all risks, we propose that management strategies to mitigate losses to biocultural resources must be approached as a restoration process of linked sociocultural and physical environmental systems.","PeriodicalId":74468,"journal":{"name":"PNAS nexus","volume":"4 4","pages":"pgaf090"},"PeriodicalIF":2.2,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11969151/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144055211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Splash-free urinals for global sustainability and accessibility: Design through physics and differential equations. 全球可持续性和可达性的无飞溅小便池：通过物理和微分方程进行设计。

IF 2.2

PNAS nexus Pub Date : 2025-04-08 eCollection Date: 2025-04-01 DOI: 10.1093/pnasnexus/pgaf087

Kaveeshan Thurairajah, Xianyu Mabel Song, J D Zhu, Mia Shi, Ethan A Barlow, Randy C Hurd, Zhao Pan

{"title":"Splash-free urinals for global sustainability and accessibility: Design through physics and differential equations.","authors":"Kaveeshan Thurairajah, Xianyu Mabel Song, J D Zhu, Mia Shi, Ethan A Barlow, Randy C Hurd, Zhao Pan","doi":"10.1093/pnasnexus/pgaf087","DOIUrl":"10.1093/pnasnexus/pgaf087","url":null,"abstract":"Urinals are a staple of public spaces yet their designs have remained essentially stagnant for over a century. The use of urinals often results in significant splatter (splashback) as urine splashes upon impact with the urinal generating droplets which travel back onto the floor and user, which generates unhygienic environments, high cleaning costs, and adds unpleasant workload for custodial staff. Impinging stream angle is one of many factors that affect splashback. We theoretically predict and experimentally validate that when the impinging angle is below an invariant critical value of <math><mo>∼</mo> <msup><mn>30</mn> <mo>∘</mo></msup> </math> , the flow rate of splashback under human urination conditions can be significantly suppressed. We propose novel urinal designs that were generated by solving differential equations derived from the isogonal curve problem to ensure the urine stream impacts at or below this critical angle. Experiments validate that these designs can substantially reduce splashback to only 1.4% of the splash of a common contemporary commercial urinal. The widespread adoption of the urinal designs described in this work would result in considerable conservation of human resources, cost, cleaning chemicals, and water usage, rendering large-scale impacts on modern society by improving sustainability, hygiene, and accessibility.","PeriodicalId":74468,"journal":{"name":"PNAS nexus","volume":"4 4","pages":"pgaf087"},"PeriodicalIF":2.2,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11976717/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143812956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Raman investigation of in vivo radiation exposure on melanin in murine hair. 体内辐射照射对小鼠毛发黑色素的拉曼研究。

IF 2.2

PNAS nexus Pub Date : 2025-04-08 eCollection Date: 2025-04-01 DOI: 10.1093/pnasnexus/pgaf108

Monika Poonia, Spencer A Witte, Mallard Woodward, Prasant Yadav, Sapna Puri, Ramasamy Santhanam, Naduparambil K Jacob, Zachary D Schultz

{"title":"Raman investigation of in vivo radiation exposure on melanin in murine hair.","authors":"Monika Poonia, Spencer A Witte, Mallard Woodward, Prasant Yadav, Sapna Puri, Ramasamy Santhanam, Naduparambil K Jacob, Zachary D Schultz","doi":"10.1093/pnasnexus/pgaf108","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgaf108","url":null,"abstract":"Determining the effects of ionizing radiation from unintended exposure in a nuclear event requires the identification of relevant biomarkers and development of methods to retrospectively estimate the absorbed dose. Melanin, a biologically important natural pigment found in hair, shows promise as a biomarker to assess potential radiation exposure. We investigated Raman spectroscopy as a rapid and noninvasive technique to assess changes in melanin from the hair of C57BL/6 mice to gamma radiation between 0 and 4 Gy. Two excitation wavelengths (532 and 785 nm) were employed to probe the melanin response for changes with radiation exposure. Excitation wavelength-dependent variation in Raman features indicates resonance Raman effects, where a 785-nm excitation is more sensitive to the effects of gamma radiation. Melanin-specific Raman features were identified as potential biomarkers for gamma-radiation exposure and used to distinguish between irradiated and nonirradiated mice. Partial least square discriminant analysis models of exposure exhibited enhanced sensitivity to irradiation at 785 nm excitation and yielded a sensitivity of 88% and a specificity of 83%. Mice were classified with 100% sensitivity and specificity up to day 7 at a known time point. A decline in specificity and classification accuracy correlated with alterations in melanin's spectra after >7 days following irradiation. Regression models of the Raman spectrum determined the exposed dose with a precision of <1 Gy at a known exposure time point. This noninvasive approach offers promising applications in radiation biodosimetry and medical monitoring, providing retrospective detection of gamma-radiation exposure at clinically relevant doses.","PeriodicalId":74468,"journal":{"name":"PNAS nexus","volume":"4 4","pages":"pgaf108"},"PeriodicalIF":2.2,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12007448/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144023035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Seasonally resolved stratigraphy at Jwalapuram India shows regional surface warming after the Toba volcanic super-eruption. 印度Jwalapuram的季节分解地层显示，多巴火山超级喷发后区域地表变暖。

IF 2.2

PNAS nexus Pub Date : 2025-04-07 eCollection Date: 2025-04-01 DOI: 10.1093/pnasnexus/pgaf109

Gopesh Jha, Mafalda Costa, Anna Tsoupra, Cristina Barrocas Dias, Ola Kwiecien, Jack Longman, Sebastian F M Breitenbach, Peter Ditchfield, Deepak Kumar Jha, Rachel Rudd, Devara Anil, Roshan Paladugu, Sindu Shree, Hema Achyuthan, Rachna Raj, K Krishnan, Nicole Boivin, Patrick Roberts, Michael Petraglia

{"title":"Seasonally resolved stratigraphy at Jwalapuram India shows regional surface warming after the Toba volcanic super-eruption.","authors":"Gopesh Jha, Mafalda Costa, Anna Tsoupra, Cristina Barrocas Dias, Ola Kwiecien, Jack Longman, Sebastian F M Breitenbach, Peter Ditchfield, Deepak Kumar Jha, Rachel Rudd, Devara Anil, Roshan Paladugu, Sindu Shree, Hema Achyuthan, Rachna Raj, K Krishnan, Nicole Boivin, Patrick Roberts, Michael Petraglia","doi":"10.1093/pnasnexus/pgaf109","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgaf109","url":null,"abstract":"Understanding the nature and tempo of global environmental responses to the ∼74,000 BP (∼74 ka) Toba volcanic super-eruption is based primarily on historical analogies and climate models that lack ground-truthing in regions distal to eruptions. Here, we report the first proxy-based terrestrial record of the immediate environmental impact of the Younger Toba Tuff (YTT) eruption on the hominin-occupied ecosystem in peninsular India, spanning six annual monsoonal cycles directly following the YTT event. We present a multiproxy paleoclimate dataset from Jwalapuram in southern India, featuring a geochemical characterization of multiple YTT tephra and hardpan layers, complemented by detailed stratigraphic observations, sedimentological insights, and stable carbon isotope data. Taken together, these multiple lines of evidence show a progressive trend of tephra weathering and strong evapotranspiration in the immediate aftermath of the YTT, suggesting multiannual regional warming. Our results underline the complex responses of regional environments to the Toba super-eruption, which extend beyond a simple widespread \"volcanic winter.\"","PeriodicalId":74468,"journal":{"name":"PNAS nexus","volume":"4 4","pages":"pgaf109"},"PeriodicalIF":2.2,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12008719/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144044124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Adverse reactions to the use of large language models in social interactions. 在社会交往中使用大型语言模型的不良反应。

IF 2.2

PNAS nexus Pub Date : 2025-04-07 eCollection Date: 2025-04-01 DOI: 10.1093/pnasnexus/pgaf112

Fabian Dvorak, Regina Stumpf, Sebastian Fehrler, Urs Fischbacher

{"title":"Adverse reactions to the use of large language models in social interactions.","authors":"Fabian Dvorak, Regina Stumpf, Sebastian Fehrler, Urs Fischbacher","doi":"10.1093/pnasnexus/pgaf112","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgaf112","url":null,"abstract":"Large language models (LLMs) are poised to reshape the way individuals communicate and interact. While this form of AI has the potential to efficiently make many human decisions, there is limited understanding of how individuals will respond to its use in social interactions. In particular, it remains unclear how individuals interact with LLMs when the interaction has consequences for other people. Here, we report the results of a large-scale, preregistered online experiment ( <math><mi>n</mi> <mo>=</mo> <mspace></mspace> <mn>3</mn> <mo>,</mo> <mn>552</mn></math> ) showing that human players' fairness, trust, trustworthiness, cooperation, and coordination in economic two-player games decrease when the decision of the interaction partner is taken over by ChatGPT. On the contrary, we observe no adverse reactions when individuals are uncertain whether they are interacting with a human or a LLM. At the same time, participants often delegate decisions to the LLM, especially when the model's involvement is not disclosed, and individuals have difficulty distinguishing between decisions made by humans and those made by AI.","PeriodicalId":74468,"journal":{"name":"PNAS nexus","volume":"4 4","pages":"pgaf112"},"PeriodicalIF":2.2,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11997303/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144043471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Revisiting the classical biodiversity-ecosystem functioning and stability relationships in microbial microcosms. 重新审视微生物微观世界中经典的生物多样性-生态系统功能和稳定性关系。

IF 2.2

PNAS nexus Pub Date : 2025-04-05 eCollection Date: 2025-04-01 DOI: 10.1093/pnasnexus/pgaf114

Jiesi Lei, Jiajie Feng, Junjun Ding, Yunfeng Yang

{"title":"Revisiting the classical biodiversity-ecosystem functioning and stability relationships in microbial microcosms.","authors":"Jiesi Lei, Jiajie Feng, Junjun Ding, Yunfeng Yang","doi":"10.1093/pnasnexus/pgaf114","DOIUrl":"https://doi.org/10.1093/pnasnexus/pgaf114","url":null,"abstract":"The question of how biodiversity influences ecosystem functioning and stability has been a central focus in ecological research. Yet, this question remains unresolved, primarily because of the widely divergent definitions of functioning, stability, and diversity. Consequently, forecasts of ecosystem services will remain speculative until we can establish more precise and comprehensive definitions for these concepts than previously. Here, we investigated how the maximum specific growth rate, productivity, mortality rate, and species interaction in microbial communities vary with a diversity gradient ranging from 1 to 16 species under control conditions, starvation, or saline stress. We found that diversity played a critical role in maintaining community growth and stability under control conditions, with higher diversity associated with increased maximum specific growth rate and decreased mortality rate. However, higher diversity was associated with an increased mortality rate under starvation, while diversity did not affect the mortality rate under saline stress. Diversity stabilized microbial productivity only under control conditions, defying the \"diversity begets stability\" hypothesis under stress. Beneficial interactions among species were prevalent in most samples, but species interaction increased mortality rates under starvation. Our findings suggest that while biodiversity is crucial for preserving ecosystem functioning and stability, the presence of multiple definitions and contextual dependence on environmental conditions argues against any general relationship between diversity and ecosystem functioning/stability. Furthermore, we provide new insights into the longstanding debate surrounding the \"diversity begets stability\" hypothesis and the \"diversity destabilizes ecosystem\" hypothesis in that diversity begets stability under control conditions but destabilizes ecosystems under severe stress.","PeriodicalId":74468,"journal":{"name":"PNAS nexus","volume":"4 4","pages":"pgaf114"},"PeriodicalIF":2.2,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12038814/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144060646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Female friendship and the cultural transmission of low-fertility values: Evidence from rural Poland. 女性友谊与低生育价值观的文化传播：来自波兰农村的证据。

IF 2.2

PNAS nexus Pub Date : 2025-04-05 eCollection Date: 2025-05-01 DOI: 10.1093/pnasnexus/pgaf113

Elena Miu, Heidi Colleran

{"title":"Female friendship and the cultural transmission of low-fertility values: Evidence from rural Poland.","authors":"Elena Miu, Heidi Colleran","doi":"10.1093/pnasnexus/pgaf113","DOIUrl":"10.1093/pnasnexus/pgaf113","url":null,"abstract":"Understanding how demographic and cultural change interact is essential for understanding the trajectory of historical and contemporary societies. While the diffusion of low-fertility values is thought to be a key process in the demographic transition, we lack a mechanistic understanding that can provide links between population-level transmission rates and individual characteristics. Here, we examine whether compositional changes in personal support networks can shape the spread of low-fertility norms and ultimately fertility outcomes. Using detailed demographic and relational data from 22 mid-transition communities in rural Poland, we show how social support partners affect key reproductive attitudes and values through shifts from kin- to nonkin-oriented friendships and from instrumental to emotional support. This shift in friendship styles appears to be driven by educated women, who exchange more emotional support with friends and who nominate fewer kin. This altered friendship composition and emotional support type is associated with low-fertility attitudes and outcomes among both postreproductive and younger women. We identify emotional support as a key moderator of ideational change in the domain of fertility norms, with implications for cultural change more broadly.","PeriodicalId":74468,"journal":{"name":"PNAS nexus","volume":"4 5","pages":"pgaf113"},"PeriodicalIF":2.2,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12046128/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144058452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0