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Ambient and passive collection of sleep and circadian data in bipolar disorder to understand symptom trajectories and clinical outcomes (AMBIENT-BD):study protocol
No full textBipolar disorder is defined by extreme variability in mood, activity and sleep/wake patterns. To date, studies of sleep and circadian parameters in bipolar disorder have predominantly relied on short term longitudinal studies with monitoring over 1-2 weeks, leaving a need for approaches that can assess individual-level changes in sleep, activity and mood with high levels of temporal granularity. In the AMBIENT-BD study, we will optimise low-interference ambient and passive data collection techniques. These methods will allow us to infer sleep and circadian timing patterns over extended time periods while developing novel data collection, sharing and analytical methods within sleep and circadian research. In parallel, we will develop data management systems to streamline and optimise data sharing within the broad research community. At its core, our project involves an 18-month prospective follow-up study focused on the assessment of sleep/wake patterns and clinical and functional outcomes in individuals with bipolar disorder. Furthermore, in collaboration with Bipolar Scotland, we will deliver a knowledge exchange programme on the theme of ‘Sleep, circadian rhythms and bipolar disorder’. AMBIENT-BD will advance our understanding of symptom trajectories and mechanisms contributing to relapse in bipolar disorder, providing valuable insights for improvements in clinical management. <br/
Expert evaluation of large language models for clinical dialogue summarization
No full textWe assessed the performance of large language models’ summarizing clinical dialogues using computational metrics and human evaluations. The comparison was done between automatically generated and human-produced summaries. We conducted an exploratory evaluation of five language models: one general summarisation model, one fine-tuned for general dialogues, two fine-tuned with anonymized clinical dialogues, and one Large Language Model (ChatGPT). These models were assessed using ROUGE, UniEval metrics, and expert human evaluation was done by clinicians comparing the generated summaries against a clinician generated summary (gold standard). The fine-tuned transformer model scored the highest when evaluated with ROUGE, while ChatGPT scored the lowest overall. However, using UniEval, ChatGPT scored the highest across all the evaluated domains (coherence 0.957, consistency 0.7583, fluency 0.947, and relevance 0.947 and overall score 0.9891). Similar results were obtained when the systems were evaluated by clinicians, with ChatGPT scoring the highest in four domains (coherency 0.573, consistency 0.908, fluency 0.96 and overall clinical use 0.862). Statistical analyses showed differences between ChatGPT and human summaries vs. all other models. These exploratory results indicate that ChatGPT’s performance in summarizing clinical dialogues approached the quality of human summaries. The study also found that the ROUGE metrics may not be reliable for evaluating clinical summary generation, whereas UniEval correlated well with human ratings. Large language models may provide a successful path for automating clinical dialogue summarization. Privacy concerns and the restricted nature of health records remain challenges for its integration. Further evaluations using diverse clinical dialogues and multiple initialization seeds are needed to verify the reliability and generalizability of automatically generated summaries
Three worlds in one:Venus as a natural laboratory for the effect of rotation period on atmospheric circulation
No full textBecause of its rotation period of 243 days, Venus is considered a slowly rotating planet. However, its persistent superrotating atmospheric jets, which increase in speed from surface to cloud tops, effectively set a faster rotation speed than the surface rotation. Using the Venus Planetary Climate Model and wind measurements taken by the Pioneer Venus entry probes, we show that the Rossby radius of deformation of the atmosphere varies with height. The atmosphere falls into three circulation regimes: (1) from the surface to 20 km, the Rossby radius of deformation exceeds the planetary radius and no Rossby waves form; (2) from 20 to 50 km, the tropical Rossby radius becomes smaller than the planetary radius, and a circulation regime characterized by a superrotating equatorial jet and mid-latitude Rossby gyres appears; (3) from 50 to 70 km, the extratropical Rossby radius becomes smaller than the planetary radius, the jet develops mid-latitude maxima, and the Rossby gyres shift to high latitudes. Studies of exoplanetary circulation regimes as a function of rotation period have repeatedly shown a similar progression. While observing the circulations of exoplanets to confirm these predictions is not currently possible, the presence of different circulation regimes on Venus and their dependence on altitude could be tested by observing campaigns. Such evidence would be the first observational support for the theory connecting differences in planetary rotation periods to circulation regime transitions and would ground predictions of exoplanet circulations in a validated framework
Diagnostic accuracy of quantitative faecal immunochemical test in symptomatic patients for the investigation of colorectal cancer once accounting for anaemia severity and iron deficiency
No full textAim: The aim of this study was to determine the diagnostic accuracy of the faecal immunochemical test (FIT) for colorectal cancer (CRC) in symptomatic patients with different levels of anaemia severity or the presence of iron deficiency.Method: Symptomatic patients (2018–2021) from primary care were followed up prospectively for CRC for 2 years. The positive predictive values (PPV) for CRC of FIT subgroups were compared between anaemia severity groups and iron deficiency groups once stratified for symptom type and demographics. The diagnostic accuracy of FIT for CRC was investigated for different definitions of iron deficiency anaemia (IDA).Results: A total of 17 538 symptomatic patients were investigated, including 310 with CRC (1.8%). In FIT < 100 μg haemoglobin (Hb)/g subgroups, the PPV for CRC was unchanged between anaemia severity levels (p > 0.05). In groups with FIT < 100 μg Hb/g, the PPV for CRC was unchanged in the presence of IDA, non-iron-deficiency anaemia and iron deficiency without anaemia (p > 0.05). In the anaemia and IDA subgroups investigated, FIT 10–19 μg Hb/g had a PPV of <3% for CRC and increasing the FIT cut-off to 20 μg Hb/g could have hypothetically saved 28.6% of colonoscopies. Including transferrin saturation in the definition of IDA increased the detection of CRC in FIT-negative patients (sensitivity 9.1% vs. 3.9%) but with a low CRC pick-up rate (PPV = 0.6%; 165 colonoscopies per CRC). Investigating FIT-negative functional IDA would increase the detection of CRC by 1.3% but with a PPV of 0.5%.Conclusion: The diagnostic accuracy of FIT is excellent regardless of the severity of anaemia, iron deficiency, symptom type or demographics. The FIT cut-off can be increased safely to 20 μg Hb/g irrespective of anaemia severity or iron deficiency. Altering the definition of IDA does not pragmatically increase the detection of CRC in negative/low FIT patients
Coordination, sensemaking, and idea work:how founding teams pivot their venture ideas
No full textThis study offers novel insights into how team structure and flexibility affect pivoting. It details how founding team coordination practices shape individual and collective sensemaking of feedback and efforts to improve a venture idea. Following seven founding teams, we identified how teams with overlapping responsibilities enjoyed the flexibility of both fragmented and holistic sensemaking. This enabled them to pivot when needed but otherwise persevere with their venture idea. In contrast, teams with clear separation of responsibilities engaged in fragmented sensemaking and only persevered with their idea. Our findings advance research on founding team coordination, pivoting, and teams' understanding of their venture ideas.</p
Compound exposure:climate change, vulnerability and the energy-extractives nexus in the Pacific
No full textA global push for an energy transition to combat climate change is fuelling demand for energy transition minerals and metals (ETMs) needed for renewable energy-systems. As the primary solution to our planetary problem, the energy transition helps to enlarge the extractive industries and increases the pressure to extract ETMs from places already acutely exposed [to] climate change, like the Pacific Islands region. In this paper we develop the concept of compound exposure to examine the combined effects of extraction and climate change in the Pacific. Drawing from a global dataset of ETM projects, we have created a first-of-kind sub-set of ETM projects in the Pacific, mapped against indicators of environmental, social, governance and climate vulnerability for the places where those projects are located. We found higher levels of situated vulnerability around ETM projects in the Pacific compared to global results. A rush for the resources in the Pacific will compound the consequences of climate change and the multiple stressors associated with resource extraction and will enlarge exposure to harm. We argue that extractivist solutions to climate change work to close off other pathways and amplify the worst effects of compound exposure in the Pacific, and beyond
Quantifying hydrothermal ammonium mobilization from sediment and implications for the marine biosphere:a case study from the Guaymas Basin, Gulf of California
No full textFluid-rock interactions in hydrothermal systems are capable of liberating ammonium (NH4+) from sedimentary organic material and making it bioavailable for benthic and pelagic microbial communities. Hydrothermal systems in organic-rich sedimentary basins are therefore thought to have played a key role in supplying bioavailable nitrogen to the early biosphere. To place new quantitative bounds on this process, we examined sediments from active hydrothermal systems in the Guaymas Basin, a young oceanic spreading center in the Gulf of California. We analysed four shallow sediment cores that were taken in the Guaymas Basin’s hydrothermally-active Southern Trough. We used a combination of isotopic tracers (δ15N, δ13C) and elemental abundances to explore nitrogen and metal mobility in buried sediments. We found that ca. 54% of the organically-bound nitrogen is remobilized by active seepage in the top 10 cm of the sediment package within as little as 27–83 yr. Extrapolating these findings over the hydrothermally-active area of the basin yields an ammonium seepage flux of ca. 1.3–4.1 mol/s. In addition, high temperature venting liberates ca. 156–187 mol/s, as estimated from previous data. Assuming biological uptake of hydrothermally recycled ammonium in the water column, these fluxes could support up to 1.3% and 58% of export productivity, respectively. Our data also reveal that the accumulation of micronutrients or potentially toxic metals is influenced by the presence of organic material in seep sediments. The Guaymas case study demonstrates that hydrothermal seepage in sedimentary basins can create a significant nutrient flux and is an efficient means of recycling nutrients from organic matter at shallow burial depths. Hydrothermal nutrient fluxes could therefore have enhanced microbial activity in Earth’s history, in particular during time intervals when Earth’s oceans are thought to have been nutrient-depleted. Our data also highlight the role of organic material in enhancing metal mobilization and accumulation in otherwise metal-starved hydrothermal seeps
When sardines disappear:tracking common dolphin, <i>Delphinus delphis</i>, distribution responses along the western Iberian coast
No full textThe common dolphin, Delphinus delphis, is the most abundant cetacean species along the western Iberian Peninsula and faces many anthropogenic threats, with bycatch being the most impactful. Its preferred prey, sardine (Sardina pilchardus), has shown fluctuating abundance over the past decade, potentially influencing dolphin distribution. This study provides the first insights into common dolphin distribution along the western Iberian coast, using sighting data from vessel research surveys (2005–2020) to identify hotspot areas while accounting for monthly and seasonal distributions overlapping with sardine abundance. Common dolphin hotspots were located along the central–western and southern Portuguese mainland coasts, coinciding with important fishing ports, oceanographic features, and sardine juvenile habitats. Furthermore, during 2013–2016, common dolphins were observed significantly farther from the coast, coinciding with a period of particularly low coastal sardine biomass. However, GAM analysis indicated that the relationship between sardine biomass and the distance of common dolphins was not significant. This study highlights the major common dolphin hotspots and presents the most comprehensive temporal and distribution maps of the common dolphin along the western Iberian coast, particularly in response to sardine availability. These results can be used by managers to inform conservation measures and for the sustainable management of the Portuguese sardine purse seine fishery fleet, which interacts the most with the species