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Bioavailable phosphite in the surface ocean during the Great Oxidation Event
No full textPhosphorus availability has influenced the co-evolution of life and Earth’s environments. While phosphate was likely the main phosphorus source for life during the Archean, phosphite (HPO32−) gained importance leading up to the Great Oxidation Event (GOE). However, the concentration of phosphite in seawater at that time, and the processes driving this shift in P utilization, remain poorly constrained. Using lab experiments and phosphite data from banded iron formations (BIFs), we show that hydrous ferric oxides (HFO) preferentially remove phosphate over phosphite. This suggests that shallow seawater at the onset of the GOE could have contained up to 0.17 µM phosphite, comprising 5–88% of total dissolved inorganic phosphorus. We propose that phosphate depletion driven by HFO adsorption and microbial competition may have promoted the use of phosphite as an alternative P source
Multi-modal, interrelated navigation in migratory birds:a data mining study
No full textUnderstanding how long-distance migratory birds navigate remains challenging, particularly in how they integrate multiple environmental cues. Traditional studies, primarily based on laboratory experiments and displacement studies, may not capture the complexity of navigation in the wild. In this study, we applied a data mining approach to investigate the navigational strategies of greater white-fronted geese (Anser albifrons) during their annual migrations between the Arctic and central Europe. We integrated a decade of tracking data from 117 individuals with high-resolution geomagnetic data (including solar-wind–induced variations), wind conditions, and a potential visual cue. Hierarchical cluster analysis revealed multi-modal and interrelated navigation strategies that flexibly adapted to environmental conditions such as wind, diurnal cycles, and flock-specific dynamics. Under favourable tailwinds, geese maintained stable headings with minimal changes in geomagnetic heading and apparent angle of geomagnetic inclination, consistent with both geomagnetic loxodrome and magnetoclinic routes, enabling efficient flights towards stopovers or simultaneously towards stopovers and final destinations. Geese also appeared to combine visual landmarks with geomagnetic information, adjusting their reliance on landmarks between day and night. Our findings highlight the complexity and adaptability of avian navigation and emphasise the role of multi-modal sensory integration and environmental context in shaping migratory decisions
Alternative treponemal serology assays for diagnosis and confirmation of syphilis in a diagnostic laboratory:a retrospective evaluation of four agglutination assays and one ELISA
No full textThe Treponema pallidum particle agglutination (TPPA) assay is no longer available in some settings. Here, we report the results of a clinical laboratory evaluation of alternative treponemal assays, including three T. pallidum hemagglutination assays (TPHAs), a T. pallidum IgG enzyme-linked immunosorbent assay (ELISA), and a detailed laboratory evaluation of the only TPHA with Australian regulatory approval. The clinical laboratory evaluation comprised 300 sera (120 TPPA reactive and 180 TPPA non-reactive) collected from individuals ≥18 years between 1 June 2021 and 1 June 2023. Median age was 33, 92% were from a sexually transmitted infection clinic, 71% were male, 15.3% were living with HIV and 5% were pregnant. Twenty-four percent had active untreated syphilis, 25% had prior treated syphilis, and 50.7% had no syphilis. Compared to TPPA, positive percent agreement (PPA) was 99.2% (95% confidence interval [CI], 95.4-99.9%), 100% (95% CI, 96.9-100%), 99.2% (95% CI, 95.4-99.9%), and 93.3% (95% CI, 87.4-96.6%), respectively, for the Arlington, Fortress, and Randox TPHAs, and Euroimmun IgG ELISA. Negative percent agreement (NPA) was 97.8% (95% CI, 94.4-99.1%) for each TPHA and 98.9% (95% CI, 96.0-99.8%) for the Euroimmun IgG ELISA. Clinical sensitivity of the Arlington and Fortress TPHAs for active untreated syphilis infection was equivalent to TPPA at 97.2% (95% CI, 90.4-99.5%) and clinical specificity of these assays was 99.3% (95% CI, 96.3-100%). In the evaluation of the NewBio TPHA, comprising 322 clinical serum and plasma samples and 22 quality assurance panel samples; overall PPA compared to TPPA was 100% (95% CI, 97.5-100%) and NPA 98.9% (95% CI, 94.1-98.9%). TPHAs are an acceptable alternative for confirmatory treponemal serology.</p
A model of the impact of government revenue and the quality of governance on electricity and clean fuel use
No full textWhen governments have more revenue, they can invest in infrastructure, such as the provision of electricity or clean fuels, which is more effective in well-governed countries. Here, we use an equilibrium correction model to empirically investigate the relationship between government revenue per capita, six indicators of quality of governance, and the proportion of the population with access to electricity and clean fuels, using an unbalanced panel dataset that includes nearly all countries in the world. The results suggest a strong effect over time: as government revenue increases, the provision of electricity and clean fuels increases, and the magnitude of this influence is mediated significantly by a country’s quality of governance. This model offers the ability to demonstrate the impact of increases and decreases in government revenue in an individual country, while accounting for the impact of revenue on governance and on the provision of electricity and clean fuels
Tax systems and policy:crucial for good health and good governance
No full textThis briefing paper highlights the critical role of tax policies and systems in advancing equitable and improved health. It explains how tax policies and systems perform five important functions that act as the bedrock for any flourishing society. These five functions are described as the five Rs of tax: Revenue, Redistribution, Representation, Repricing and Regulation. However, current tax policies and systems, particularly in the global South, are failing. In many low-income countries, tax revenues make up a small percentage of GDP and are regressive. And across the world, tax avoidance and evasion, particularly by trans-national corporations and wealthy elites, are a fundamental driver of social, economic, and political inequalities. This paper explains why national and international tax policies and systems are failing society and argues that the health community must engage more actively in advocating for comprehensive tax reforms, recognising that tax policies play a pivotal role in creating just, peaceful, and healthy societies. It stresses the need for health professionals to participate in national and international tax policy discussions, collaborate with movements for tax justice, and hold governments accountable, particularly in the context of the ongoing UN tax convention negotiations. Reformed tax systems are presented as crucial tools for reducing inequality and fostering better health outcomes worldwide
PTGaze: Cross-domain gaze estimation via proxy tuning
No full textTo tackle the cross-domain model performance degradation challenge, a gaze estimation method based on proxy tuning is proposed, called PTGaze. In PTGaze, an base model is used to learn the gaze representation of the baseline model in the source domain, and an adapt model is used to learn the gaze representation of the baseline model in the target domain. The gaze difference between the base and adapt models is utilized to guide the final output, ensuring the method’s accuracy in the target domain. Experimental results show that the proposed method achieves higher cross-domain gaze estimation accuracy on five public datasets, using RT-Gene, Full-face, and Gaze360 as baseline models
A Lost but Truly Great Russian Novel
No full textNJЁ ROMAN I HUMBUR RUS, VЁRTET I MADH [A Lost but Truly Great Russian Novel] (translated from the English into Albanian by Bardhyl Selimi) (pp. 67-82). 2025. DULINGVA BULTENO DE LA ALBANA ESPERANTO – INSTITUTO / Buletini dygjuhësh i Institutit Shqiptar të Esperantos. No. 186, (maj-qershor 2025, majo-junio 2025
The Global AI Race and Infrastructure Weaponization
No full textGara globale dhe Armatosja e Infrastrukturës [The Global AI Race and Infrastructure Weaponization] (translated from the English into Albanian by Bardhyl Selimi). 2025. Kosova Lindore. 22 May. http://www.kosovalindore.com/gara-globale-dhe-armatosja-e-infrastruktures
Fine-scale residency and temperature-driven habitat selection in a migratory shark species
No full textMany marine species exhibit complex and diverse movements that vary across spatial and temporal scales. These movements must be accounted for when designing effective management and conservation efforts. While environmental cues such as temperature and salinity have been shown to influence the movements of mobile species, it is increasingly documented that social factors can also influence space use and population behaviour. Understanding how various factors influence movement enhances our ability to predict the space use of highly dynamic ocean species. Spurdog (Squalus acanthias), known for their tendency to aggregate and use of both coastal and oceanic environments, are an ideal model species for studying drivers of movement. To investigate movement and habitat selection in spurdog, we conducted an acoustic telemetry study from June 2016 to July 2017, tagging 51 spurdog in a partially enclosed fjordic sea loch on the west coast of Scotland. The thermal profile of Loch Etive was recorded to complement the movement data. Our study revealed temperature as a pivotal driver of movement and habitat selection in spurdog, with the unique thermal environment of the fjord enabling year-round residency at a previously undocumented spatial scale, suggesting that such habitats may be especially important for mobile marine species. This study demonstrates the importance of understanding environmental influences on space use and movement to develop effective, climate-resilient management strategies for spurdog and other mobile marine species.</p
2′,7′-Dimethyl-3H-spiro[isobenzofuran-1,9′-xanthen]-3-one
No full textA synthetic route to 2′,7′-dimethyl-3H-spiro[isobenzofuran-1,9′-xanthen]-3-one has been described using methanesulfonic acid in place of reagents described in protocols from the early 20th century. A full NMR assignment has been made and X-ray crystallography has been used to characterise the title compound for the first time