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The amount of methane released to the atmosphere from the Nord Stream subsea pipeline leaks remains uncertain, as reflected in a wide range of estimates 1-18 . A lack of information regarding the temporal variation in atmospheric emissions has made it challenging to reconcile pipeline volumetric (bottom-up) estimates 1-8 with measurement-based (top-down) estimates 8-18 . Here we simulate pipeline rupture emission rates and integrate these with methane dissolution and sea-surface outgassing estimates 9,10 to model the evolution of atmospheric emissions from the leaks. We verify our modelled atmospheric emissions by comparing them with top-down point-in-time emission-rate estimates and cumulative emission estimates derived from airborne 11 , satellite 8,12-14 and tall tower data. We obtain consistency between our modelled atmospheric emissions and top-down estimates and find that 465 ± 20 thousand metric tons of methane were emitted to the atmosphere. Although, to our knowledge, this represents the largest recorded amount of methane released from a single transient event, it is equivalent to 0.1% of anthropogenic methane emissions for 2022. The impact of the leaks on the global atmospheric methane budget brings into focus the numerous other anthropogenic methane sources that require mitigation globally. Our analysis demonstrates that diverse, complementary measurement approaches are needed to quantify methane emissions in support of the Global Methane Pledge 19 ., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. United Nations Environment Programme and the Authors.)

The impact of adverse listening conditions on spoken language perception is well established, but the role of suboptimal viewing conditions on signed language processing is less clear. Viewing angle, i.e. the physical orientation of a perceiver relative to a signer, varies in many everyday deaf community settings for L1 signers and may impact comprehension. Further, processing from various viewing angles may be more difficult for late L2 learners of a signed language, with less variation in sign input while learning. Using a semantic decision task in a distance priming paradigm, we show that British Sign Language signers are slower and less accurate to comprehend signs shown from side viewing angles, with L2 learners in particular making disproportionately more errors when viewing signs from side angles. We also investigated how individual differences in mental rotation ability modulate processing signs from different angles. Speed and accuracy on the BSL task correlated with mental rotation ability, suggesting that signers may mentally represent signs from a frontal view, and use mental rotation to process signs from other viewing angles. Our results extend the literature on viewpoint specificity in visual recognition to linguistic stimuli. The data suggests that L2 signed language learners should maximise their exposure to diverse signed language input, both in terms of viewing angle and other difficult viewing conditions to maximise comprehension., (© 2024. The Author(s).)

Atmospheric methane growth reached an exceptionally high rate of 15.1 ± 0.4 parts per billion per year in 2020 despite a probable decrease in anthropogenic methane emissions during COVID-19 lockdowns 1 . Here we quantify changes in methane sources and in its atmospheric sink in 2020 compared with 2019. We find that, globally, total anthropogenic emissions decreased by 1.2 ± 0.1 teragrams of methane per year (Tg CH 4 yr -1 ), fire emissions decreased by 6.5 ± 0.1 Tg CH 4  yr -1 and wetland emissions increased by 6.0 ± 2.3 Tg CH 4  yr -1 . Tropospheric OH concentration decreased by 1.6 ± 0.2 per cent relative to 2019, mainly as a result of lower anthropogenic nitrogen oxide (NO x ) emissions and associated lower free tropospheric ozone during pandemic lockdowns 2 . From atmospheric inversions, we also infer that global net emissions increased by 6.9 ± 2.1 Tg CH 4  yr -1 in 2020 relative to 2019, and global methane removal from reaction with OH decreased by 7.5 ± 0.8 Tg CH 4  yr -1 . Therefore, we attribute the methane growth rate anomaly in 2020 relative to 2019 to lower OH sink (53 ± 10 per cent) and higher natural emissions (47 ± 16 per cent), mostly from wetlands. In line with previous findings 3,4 , our results imply that wetland methane emissions are sensitive to a warmer and wetter climate and could act as a positive feedback mechanism in the future. Our study also suggests that nitrogen oxide emission trends need to be taken into account when implementing the global anthropogenic methane emissions reduction pledge 5 ., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Nitrous oxide (N 2 O), like carbon dioxide, is a long-lived greenhouse gas that accumulates in the atmosphere. Over the past 150 years, increasing atmospheric N 2 O concentrations have contributed to stratospheric ozone depletion 1 and climate change 2 , with the current rate of increase estimated at 2 per cent per decade. Existing national inventories do not provide a full picture of N 2 O emissions, owing to their omission of natural sources and limitations in methodology for attributing anthropogenic sources. Here we present a global N 2 O inventory that incorporates both natural and anthropogenic sources and accounts for the interaction between nitrogen additions and the biochemical processes that control N 2 O emissions. We use bottom-up (inventory, statistical extrapolation of flux measurements, process-based land and ocean modelling) and top-down (atmospheric inversion) approaches to provide a comprehensive quantification of global N 2 O sources and sinks resulting from 21 natural and human sectors between 1980 and 2016. Global N 2 O emissions were 17.0 (minimum-maximum estimates: 12.2-23.5) teragrams of nitrogen per year (bottom-up) and 16.9 (15.9-17.7) teragrams of nitrogen per year (top-down) between 2007 and 2016. Global human-induced emissions, which are dominated by nitrogen additions to croplands, increased by 30% over the past four decades to 7.3 (4.2-11.4) teragrams of nitrogen per year. This increase was mainly responsible for the growth in the atmospheric burden. Our findings point to growing N 2 O emissions in emerging economies-particularly Brazil, China and India. Analysis of process-based model estimates reveals an emerging N 2 O-climate feedback resulting from interactions between nitrogen additions and climate change. The recent growth in N 2 O emissions exceeds some of the highest projected emission scenarios 3,4 , underscoring the urgency to mitigate N 2 O emissions.

High throughout sequencing has provided an unprecedented view of the circulating diversity of all classes of human herpesviruses. For herpes simplex virus 1 (HSV-1), we and others have previously published data demonstrating sequence diversity between hosts. However the extent of variation during transmission events, or in one host over years of chronic infection, remain unknown. Here we present an initial example of full characterization of viruses isolated from a father to son transmission event. The likely occasion of transmission occurred 17 years before the strains were isolated, enabling a first view of the degree of virus conservation after decades of recurrences, including transmission and adaptation to a new host. We have characterized the pathogenicity of these strains in a mouse ocular model of infection, and sequenced the full viral genomes. Surprisingly, we find that these two viruses have preserved their phenotype and genotype nearly perfectly during inferred transmission from father to son, and during nearly two decades of episodes of recurrent disease in each human host. Given the close genetic relationship of these two hosts, it remains to be seen whether or not this conservation of sequence will occur during non-familial transmission events.

We demonstrate that the inclusion of a small amount of the co-solvent 1,8-diiodooctane in the preparation of a bulk-heterojunction photovoltaic device increases its power conversion efficiency by 20%, through a mechanism of transient plasticisation. We follow the removal of 1,8-diiodooctane directly after spin-coating using ellipsometry and ion beam analysis, while using small angle neutron scattering to characterise the morphological nanostructure evolution of the film. In PffBT4T-2OD/PC 71 BM devices, the power conversion efficiency increases from 7.2% to above 8.7% as a result of the coarsening of the phase domains. This coarsening process is assisted by thermal annealing and the slow evaporation of 1,8-diiodooctane, which we suggest, acts as a plasticiser to promote molecular mobility. Our results show that 1,8-diiodooctane can be completely removed from the film by a thermal annealing process at temperatures ≤100 °C and that there is an interplay between the evaporation rate of 1,8-diiodooctane and the rate of domain coarsening in the plasticized film which helps elucidate the mechanism by which additives improve device efficiency.

We have used Soxhlet solvent purification to fractionate a broad molecular weight distribution of the polycarbazole polymer PCDTBT into three lower polydispersity molecular weight fractions. Organic photovoltaic devices were made using a blend of the fullerene acceptor PC₇₁BM with the molecular weight fractions. An average power conversion efficiency of 5.89% (peak efficiency of 6.15%) was measured for PCDTBT blend devices with a number average molecular weight of Mn = 25.5 kDa. There was significant variation between the molecular weight fractions with low (Mn = 15.0 kDa) and high (Mn = 34.9 kDa) fractions producing devices with average efficiencies of 5.02% and 3.70% respectively. Neutron reflectivity measurements on these polymer:PC₇₁BM blend layers showed that larger molecular weights leads to an increase in the polymer enrichment layer thickness at the anode interface, this improves efficiency up to a limiting point where the polymer solubility causes a reduction of the PCDTBT concentration in the active layer.

Objectives: To establish the prevalence of the risk of undernutrition, using criteria similar to those used by the Malnutrition Advisory Group (MAG), in people aged 65 y and over, and to identify relationships between risk of undernutrition and health and demographic characteristics., Design: A cross-sectional nationally representative sample of free-living and institutionalized older people in the UK (65 y of age and over). Secondary analysis of the National Diet and Nutrition Survey based on 1368 people aged 65 y and over., Results: About 14% (21% in those living in institutions) were at medium or high risk of undernutrition based on a composite measure of low body mass index and recent reported weight loss. Having a long-standing illness was associated with a statistically significantly increased risk of undernutrition (odds ratio: men 2.34, 95% CI 1.20-4.58; women 2.98; 1.58-5.62). The risk of undernutrition increased: in women reporting bad or very bad health status; in men living in northern England and Scotland; for those aged 85 y and older; for those hospitalized in the last year, and those living in an institution. Lower consumption of energy, meat products or fruit and vegetables and lower blood measures of zinc, vitamins A, D, E and C were associated with statistically significantly increased risk of undernutrition., Conclusions: A substantial proportion of the older population of the UK is at risk of undernutrition. High-risk subjects are more likely to have poorer health status. It is unlikely that the individuals at high risk are being detected currently, and therefore effective care is not being provided, either in the community or in institutions.

Objective: To investigate the views and opinions on weight loss treatments of adult obese patients attending a dietetic clinic., Design: Cross-sectional survey., Subjects: 161 adults attending dietetic outpatients clinics in Portsmouth for obesity with a body mass index of at least 30 kg/m2., Measurements: Self-administered questionnaire developed from a series of focus groups with obese adults. Key topics were previous attempts to lose weight, methods used, the role of physical activity and patients' views about treatment from health professionals., Results: The preferences and usefulness of different methods to lose weight varied according to the number of attempts to lose weight, gender, age, body mass index and medical condition of the patient. Men were less likely to use special slimming products, attend slimming groups and swimming than women (odds ratios (95% confidence interval), 0.1 (0.03-0.6) for slimming groups other than Weight Watchers, 0.3 (0.1-0.80) for special slimming products and 0.3 (0.1-0.6) for swimming). Men were more likely to use physical activity (2.6 (1.1-6.2)) and in particular walking (3.7 (1.0-13.6)) and cycling (2.8 (1.0-7.6)) and were more likely to see the dietitian (3.8 (1.4-9.9)) than women. Those with more than 10 attempts to lose weight were more likely to see the dietitian (3.6(1.6-8.2)), use Weight Watchers (2.5 (1.1-5. 6)) and newspapers and magazines (4.4 (1.8-10.9)) than those with fewer attempts. The younger age group were more likely to use more vigorous forms of exercise (4.2 (1.6-11.2) for keep fit and 3.7 (1. 5-9.6) for cycling) than the older subjects. The most obese were more likely to have negative views on their treatment by health professionals (4.4 (1.9-9.8) 'chairs are never big enough' and 4.0 (1.8-8.8) 'I am regarded as a second class citizen') than those who were less obese. Those without a medical condition were more likely to exercise (2.8 (1.3-6.3)) and use books (4.8 (2.0-11.2)) than those with a medical condition., Conclusion: The views of obese people should be considered when planning services for the treatment of obesity and a variety of options should be available. International Journal of Obesity (2000) 24, 164-170

To assess the extent to which current dietary habits conform with the national nutritional guidelines aimed at reducing the high national mortality from coronary heart disease (CHD), 203 of 275 men (74 per cent) aged 40-59 years in a London community provided a weighed record of all food and drink consumed over 5 d. Satisfactory records were returned by 170 men weighing at least 75 per cent of their intakes, including 43 on medical or self-imposed diets. Mean (s.d.) energy intake was 2476 (590) kcal (10.38 MJ), comprising 37 per cent fat, 42 per cent carbohydrate, 14.7 per cent protein and 6.3 per cent alcohol. Butter or butter spreads were used by 53 per cent, sunflower margarine by 29 per cent and low fat spreads by 13 per cent; lard or dripping was used by 23 per cent of households as the main cooking fat. Intakes of vitamins and trace elements were generally above recommended amounts. These results are closely comparable with the only similar studies for the UK undertaken in Wales and Scotland. Compared with national guidelines, only 32 per cent of men met the short-term goals for fat intake, and even fewer the long-term goals. Carbohydrate and fibre intake remained too low. Alcohol intake exceeded the short-term goal (5 per cent of energy of less) in 36 per cent of men. Greater public health effort will be needed to reduce fat intake further for primary prevention of CHD, particularly as habitual intake is probably underestimated by the weighed dietary record.