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Large domal stromatolites in the Paleoarchean ocean at 3.47 Ga
No full textFunding: E.E. Stüeken acknowledges funding from a Natural Environment Research Council (NERC) Frontiers grant (NE/V010824/1) and from a Leverhulme Trust research grant (RPG-2022-313).Stromatolites are indicators of life on Earth since at least 3.5 Ga and possibly 3.7 Ga. From the mid-Archean onward, records of stromatolites display a range of morphologies and sizes, indicating that microorganisms were present in a variety of habitats. By comparison, the existing Paleoarchean stromatolite record is limited to small decimeter-scale domes, cones, and tufts that occur in evaporitic environments. Here, we document large domal stromatolites with ∼1.5 m width and 0.8 m height from a chert-jasper-carbonate member in the Paleoarchean (ca. 3.47 Ga) Mount Ada Basalt, Pilbara craton, Western Australia. Sedimentological features and trace-element chemistry show that the stromatolites grew on seafloor pillow basalts in an anoxic environment with hydrothermal influence. Aqueous alteration of basaltic-komatiitic crust likely supplied key nutrients, extending benthic microbial habitats into the deeper Paleoarchean ocean and supporting a thriving biosphere independent of continental exposure.Peer reviewe
The role of mergers and rejuvenation in the buildup of the quiescent population at cosmic noon
No full textFunding: This work was supported by the Science and Technology Facilities Council (STFC) grants ST/X000982/1 and ST/X006581/1. VW acknowledges the STFC grant ST/Y00275X/1 and Leverhulme Research Fellowship RF-2024-589/4. We gracefully acknowledge support from the NASA Astrophysics Data Analysis Programme (ADAP) under grant 80NSSC23K0495.We investigate the quenching of galaxies using a mock observational light-cone generated from the Semi-Analytic Model (SAM) L-Galaxies, closely matched to observations from the UKIDSS Ultra Deep Survey (UDS). The sample is used to study merging, rejuvenation, and visibility times for star-forming, quiescent, and post-starburst (PSB) galaxies, to assess the impact on the buildup of the passive galaxy mass functions. We find, for example, that a typical PSB (M∗ ∼ 1010 M☉) at z ≈ 1 has a 15 per cent likelihood of merging and around a 25 per cent likelihood of rejuvenating within 1 Gyr of being identified. Applying these rates and time-scales to the observational data, we estimate the fraction of quiescent galaxies that passed through a PSB phase. We find that 18–28 per cent of the build-up in the massive end (M∗ > 1010 M☉) of the passive mass function at 1 < z < 2 can be explained by PSBs, with the contribution declining to ∼ 5 per cent by z ≃ 0.5. Accounting for mergers and rejuvenation reduces the inferred PSB contribution by approximately a factor of two. At lower stellar masses (M∗ < 1010 M☉), rapid quenching through a PSB phase explains a significantly larger fraction of the growth in the passive mass function. With a visibility time of ∼0.75 Gyr, we find that around 60–80 per cent of low-mass passive galaxies underwent a PSB phase. Our findings provide further evidence that low- and high-mass galaxies follow different quenching pathways.Peer reviewe
The Outbursting YSOs Catalogue (OYCAT)
No full textFunding: C.C.P. was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MEST) (No. 2019R1A6A1A10073437). J.E.L. was supported by the New Faculty Startup Fund from Seoul National University and the NRF grant funded by the Korean government (MSIT) (grant number 2021R1A2C1011718 and RS-2024-00416859). GJH is supported by the National Key R&D program of China 2022YFA1603102 and by general grant 12173003 from the National Natural Science Foundation of China. D.J. is supported by NRC Canada and by an NSERC Discovery Grant. A.K. was supported by the NKFIH excellence grant TKP2021-NKTA-64. Zs.N. acknowledges the Hungarian National Research, Development and Innovation Office grant OTKA FK 146023. Zs.N. was supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences. Zs.N. acknowledges support from the ESA PRODEX contract No. 4000132054. Zs.M.Sz. acknowledges funding from a St. Leonards scholarship from the University of St. Andrews. Zs.M.Sz. is a member of the International Max Planck Research School (IMPRS) for Astronomy and Astrophysics at the Universities of Bonn and Cologne. A.C.G. acknowledges support from PRIN-MUR 2022 20228JPA3A “The path to star and planet formation in the JWST era (PATH)” funded by NextGeneration EU and by INAF-GoG 2022 “NIR-dark Accretion Outbursts in Massive Young stellar objects (NAOMY)” and Large Grant INAF 2022 “YSOs Outflows, Disks and Accretion: towards a global framework for the evolution of planet forming systems (YODA)”. F.C.S.M. received financial support from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (ERC Starting Grant “Chemtrip”, grant agreement No 949278). G.B was supported by Basic Science Research Program through the National Research Foundation ofKorea(NRF) funded by the Ministry of Education(grant number RS-2023-00247790). Z.G. is funded by ANID, Millennium Science Initiative, AIM23-001. Z.G. is supported by the China-Chile Joint Research Fund (CCJRF No.2301) and Chinese Academy of Science South America Center for Astronomy (CASSACA) Key Research Project E52H540301. This work was also supported by the NKFIHNKKPgrantADVANCED149943. Project no.149943 has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the NKKP ADVANCED funding scheme.Young stellar objects (YSOs) can display unpredictable and high-amplitude rises in brightness that can last from a few months to possibly over 100 years. These types of outbursts are explained by large changes in the mass accretion rate from the disk onto the central star. This type of variability has given support to a model of star formation (episodic accretion) where stars would spend most of their lifetimes accreting at low rates, and gain most of their mass through these short-lived accretion outbursts. The universality of episodic accretion, as well as its potential impact on stellar and planetary formation are still under debate. Improvement on the statistics of the members of the eruptive class is needed to better understand the episodic accretion phenomenon and its universality across different mass regimes and environments. In this paper we collect published information on the spectroscopic and photometric characteristics of 174 YSOs confirmed to belong to the eruptive variable class. We classify these objects into five different sub-classes (we find 49 FUor, 20 FUor-like, 16 EX Lupi-type, 81 Peculiar/V1647 Ori-like/MNors and 8 Periodic YSOs). The classification follows what has been done previously in the literature, and it is not an attempt to redefine these classes. In addition, we present a list of 18 embedded, and 6 massive YSOs, as additional categories of eruptive variable YSOs. Due to the complexity and/or faintness of these systems, it is hard to place them into the original classification scheme of this class of variable YSOs. Finally, we present a separate list of 355 candidate eruptive variable YSOs, which either lack spectroscopic information or the available spectroscopic data is not sufficient for an unambiguous classification. The online catalogue of confirmed and candidate eruptive YSOs will be maintained and updated in the future to serve as an important reference for the star formation community.Peer reviewe
An impact evaluation of the Scottish take-home naloxone programme
No full textObjectives: To describe the change in opioid-related deaths (ORDs) recorded across Scotland since National ‘Take Home’ Naloxone Programme (NNP) implementation between baseline pre-implementation (2006 – 2010) and 10-year post implementation (2011 – 2020) periods. To describe and contextualise the change in ORDs within 4 weeks of prison release and hospital discharge across the same pre- and post-implementation periods and evaluate the reach of naloxone to people at risk of opioid overdose during this period. Methods: Descriptive statistics as part of a pre-post secondary contribution analysis approach. The Better Evaluation Rainbow Framework for impact evaluation was utilised and data was obtained from official statistics and monitoring reports via Public Health Scotland. Results: An increase in total ORDs nationwide was observed post-NNP implementation. In 2006–10, 9·8 % of ORDs (193 of 1970) were in people released from prison within 4 weeks of death, whereas only 4·4 % of ORDs (281 of 6439) in 2011–20 followed prison release, representing a 55 % reduction. A similar reduction in ORDs following hospital discharge was not observed. Cumulative reach of take-home naloxone to individuals at risk of opioid overdose across the post-implementation period was 58 %. Conclusions: Implementation of the Scottish NNP has coincided with an increase in total ORDs nationwide, increased availability of take-home naloxone for management of opioid overdose and a reduction in the proportion of opioid-related fatalities among recently released prisoners. Unfortunately, the proportion ORDs after hospital discharge remain unchanged suggesting that this population may benefit from further research and additional distribution approaches.Peer reviewe
Changing EAP assessment practices in the age of generative artificial intelligence : the case of Scottish higher education institutions
No full textThe impact of generative artificial intelligence (GenAI) on higher education has been widely discussed since the public release of ChatGPT-3.5 in late 2022. However, there has been little empirical research on changes in English-for-Academic-Purposes (EAP) assessment practices in response to GenAI. This qualitative case study intends to fill this gap by examining how Scottish universities changed EAP assessments in response to GenAI, how effective those changes were perceived by EAP academics, and what recommendations EAP academics offered for future assessment practices. Data were collected from six semi-structured interviews conducted with EAP academics at five Scottish universities in mid-2024 and thematically analysed. The findings reveal that while substantial changes in assessment task design were limited, modifications to task requirements (e.g., GenAI declarations, context-specific prompts) and grading practices were more common. Moreover, our participants expressed scepticism about the effectiveness of some changes (e.g., AI use declarations) but positively perceived others (e.g., the use of context-specific questions, spontaneous speaking tasks, and named marking). As for their recommendations, the participating EAP academics generally advocated authentic and innovative tasks, such as portfolio-based assessment, reflections, multimodal projects, and GenAI output evaluation over reverting to traditional exams while simultaneously highlighting issues with workload and learning outcomes. The study implies a need for clearer institutional guidance, ongoing professional dialogue, and support for experimentation with GenAI-integrated assessment design in EAP contexts.Peer reviewe
Urban-rural disparity : temporal trends in dementia prevalence and the impact of demographic transition in Taiwan (2000–2020)
No full textFunding: This study is supported by the National Science and Technology Council (Taiwan) grant (MOST 109-2423-H-037-001-SS3, NSTC 112-2628-H-037 -002 -MY3; MOST109-2321-B-037-001, MOST110-2321-B-037-003, and MOST111-2321-B-037-003), and partial support from British Academy (grant no: SRG24\242178).Objectives While the simultaneous rise of two major demographic trends—population aging and urbanization—has created significant global challenges, the long-term demographic impact on dementia prevalence remains unclear. This study aimed to examine temporal trends and urban–rural differences in dementia prevalence over a 20-year period (2000–2020) in Taiwan. Methods This study analyzed cross-sectional trends in dementia prevalence between urban and rural areas in Taiwan over five time points (2000, 2005, 2010, 2015, 2020) using the full population National Health Insurance database. Logistic regression models estimated adjusted odds ratios (AORs) for urban–rural comparisons of dementia prevalence, reporting AORs with 95% CI. Results Urbanization among older adults rose from 63.4% to 73.0%, alongside rising dementia prevalence in both settings. Initially higher in urban areas (2.79% vs. 2.56% in 2000), rural prevalence surpassed urban prevalence around 2010–2015 and widened by 2020 (8.23% rural vs. 6.81% urban). AORs for urban vs. rural prevalence declined from 1.02 (95% CI: 0.99–1.04) in 2000 to 0.95 (0.94–0.96) in 2020. Discussion This study highlights the significant impact of population aging and urbanization on dementia prevalence in Taiwan over two decades. Dementia prevalence increased markedly across both urban and rural areas, with rural areas surpassing urban prevalence between 2010 and 2015, likely due to decentralized healthcare and long-term care policies. These findings underscore the need for tailored dementia care strategies, especially in rural settings, to inform effective public health planning.Peer reviewe
Random encounter modelling as a viable method to estimate absolute abundance of reef fish
No full textFunding: Leverhulme Trust (grant number RC-2018-021); CEAUL, Fundação para a Ciência e a Tecnologia (grant number 10.54499/UIDB/00006/2020); National Science Foundation–Natural Environment Research Council Biological Oceanography Grant (grant number 1948946) and European Research Council (grant number GA 101044975).1. Remote underwater video (RUV) surveys are increasingly replacing diver-based underwater visual censuses (UVCs) in fish ecology studies, especially on coral reefs. However, extracting reliable estimates of abundance or density from video footage is a major challenge, with most studies using a metric of relative abundance, MaxN (maximum number of concurrent conspecific individuals). 2. Here we compare a video survey density estimation method used in terrestrial wildlife management, random encounter staying time modelling (REST) to MaxN from unbaited videos and density estimates from diver-based UVC. We assess and compare the three approaches according to labour intensiveness (survey time effort per m2), species detection, abundance estimates and potential biases against size or aggregation behaviour. 3. We found that species detection in REST was highly sensitive to sampling effort due to the minimum number of detections required for model fitting. There was also considerable variation in REST-estimated absolute densities between species compared with other methods, however, each method was able to detect compositional differences among sites. While UVC was far less labour intensive than REST or MaxN in survey and processing effort, species richness was consistently lower in UVC observations compared to that from the two video-based approaches. Pairwise generalised linear mixed models between method abundances showed that UVC abundances tended to be higher than other methods for shoaling/schooling fish. 4. Our study identified strengths and weaknesses in each method for specific research objectives that may prioritise species detections or precision in abundance estimates. Although labour intensive, we found REST a viable alternative to MaxN if absolute abundance estimates are preferred. If precise abundance estimates are not a priority and labour is limited, we found MaxN suitable for capturing species richness. Finally, UVC ranked best in labour effectiveness in terms of both person-hours and spatial coverage, and it provided good estimates of abundance, but generally lower species richness. Ultimately, method selection depends on study-specific priorities and trade-offs.Peer reviewe
Hepatic safety of pretomanid-and pyrazinamide-containing regimens in TB Alliance clinical trials
No full textFunding: This work was supported by TB Alliance (Global Alliance for TB Drug Development) with funding from Australia’s Department of Foreign Affairs and Trade, the Gates Foundation [OPP1129600], the Foreign, Commonwealth and Development Office (United Kingdom), Germany’s Federal Ministry of Education and Research through KfW, Irish Aid, and the United States Agency for International Development.BACKGROUND: In STAND and SimpliciTB, clinical trials for drug-susceptible TB, regimens containing pretomanid, pyrazinamide, and other agents (PaZX) had more hepatotoxicity than the standard-of-care regimen of isoniazid, rifampicin, pyrazinamide, and ethambutol (HRZE). In Nix-TB and ZeNix, clinical trials for drugresistant TB, the regimen of bedaquiline, pretomanid, and linezolid (BPaL) demonstrated a favorable benefitrisk profile. We compare the hepatic safety of HRZE, PaZX, and BPaL in their respective populations. METHODS: In this post-hoc analysis of data from six clinical trials, rates of treatment-emergent elevations of alanine transaminase (ALT) during the first 8 weeks of treatment were estimated by Kaplan-Meier (KM) analysis and compared via log-rank testing and Cox modeling. RESULTS: The KM-estimated probabilities of treatment-emergent ALT elevations greater than 3x the upper limit of normal (.3xULN) were 5.36%, 12.7%, and 11.4% for HRZE, PaZX, and BPaL, respectively. The only significant (p, 0.05) difference was HRZE versus PaZX. The probabilities of ALT elevations .8xULN were 2.68%, 4.58%, and 1.05%, with the only significant difference being PaZX versus BPaL. CONCLUSIONS: BPaL and HRZE have similar hepatic safety profiles in their respective populations. Pretomanid and pyrazinamide should be co-administered only when the benefit outweighs the risk.Peer reviewe
Moderate levels of high-frequency noise mask harbor porpoise hearing, but do not cause temporary threshold shift
No full textFunding: This work was funded by the Nordic Council of Ministers and ONR Grant Nos. N00014-19-1-2332 and N00014-20-1-2709. Equipment was sponsored FNU grants to P.T.M.The potential for masking and temporary threshold shift (TTS) of a harbor porpoise exposed to high-frequency noise was investigated using levels and a duration that match likely vessel noise exposures at sea. An auditory evoked potential (AEP) technique allowed immediate assessment of hearing sensitivity during and after 20 s noise exposures centered on the 125 kHz 1/3 octave band. When the noise was delivered concomitantly with the stimuli, a 125 kHz 1/3 octave level of 85 dB re 1 μPa root mean square (rms) was enough to mask the hearing of click energy levels of 83 and 97 dB re 1 μPa2 s, and no AEPs could be measured when the noise reached a rms level of 120 dB re 1 μPa rms. These masking levels in the 100-150 kHz echolocation and communication band of porpoises are realized at ranges of several hundred meters from vessels with screws causing cavitations. After a period of more intense noise exposure level up to 147 dB re 1 μPa2 s at 125 kHz, responses to the click stimuli were not lower than at baseline levels. Since exposure levels this high are rarely encountered at high frequencies, it is therefore unlikely that high-frequency components of vessel noise can cause TTS, even in harbor porpoises within 10 s of meters of passing vessels. The AEP responses observed after exposures support the hypothesis that harbor porpoises can actively reduce their hearing sensitivity during noise exposure to maintain high hearing acuity immediately after exposure.Peer reviewe
Advanced mass spectrometry-based characterisation of plasma in the context of oesophageal cancer, obesity, and metal–protein interactions
No full textThis thesis sought to investigate the systemic molecular alterations in the plasma proteome, metallome and metabolome across metabolic and oncological disease, offering a comprehensive characterisation of circulating biomolecules that drive physiological adaptation and pathological responses. The primary objective was to decipher how changes in plasma composition reflect underlying molecular remodelling during disease progression and recovery using a range of high-throughput omics approaches.
Proteomic, metabolomic, and metalloproteomic analyses were conducted to explore systemic molecular changes in oesophageal adenocarcinoma (OAC) and metabolic diseases. SWATH-MS proteomics of OAC plasma identified distinct molecular signatures linked to treatment response: responders to chemotherapy showed increased immune-related proteins, while those responding to chemoradiotherapy exhibited activation of haemostatic and regenerative pathways. Poor responders in both groups displayed proteolytic suppression and immune-metabolic imbalance. Metabolomic profiling via LC-MS/MS pinpointed propionyl-carnitine as a potential marker of favourable chemotherapy response. Conversely, multiple metabolites involved in amino acid, nucleotide, choline, and arginine metabolism were associated with poor chemoradiotherapy outcomes, indicating metabolic pathway reprogramming associated with resistance. Longitudinal SWATH-MS analysis of plasma from patients undergoing Roux-en-Y gastric bypass revealed systemic proteomic reorganisation, including increased SHBG, ITIH3, and ApoD, along with decreased coagulation proteins (A2M, KLKB1, F10–F12), suggesting lowered thrombotic risk and better vascular health. Metalloproteomic studies showed coordination between plasma proteins and trace elements, implying that kininogen may compensate for Zn²⁺ binding when albumin affinity shifts. Notably, ceruloplasmin and transferrin strongly correlated with copper and iron levels, respectively.
Collectively, this thesis highlights the potential of plasma proteins and their ability to dynamically respond to diverse pathological states and metabolic conditions and the ability to quantify these changes using high-throughput MS techniques. Thus, this work highlights the cutting-edge MS-driven omics strategies in elucidating disease mechanisms, providing a foundation for biomarker discovery, mechanistic validation and the advancement of translational and systems medicine."I am grateful to Tenovus Scotland (grant no T19-05) and the University of St Andrews School of Medicine for funding this project."--Fundin
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