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Large eddy simulation of dual-fuel swirl flames
Full text linkDual-fuel combustion, where fuels of different reactivity are injected in the combustor separately in time or space, is important for some practical applications. This study employs Large Eddy Simulation (LES) coupled with the Doubly-Conditioned Moment Closure (DCMC) model to investigate dual-fuel flames, where liquid n-heptane (C7H16) is injected into a lean premixed methane/air (CH4/air) swirling stream. Two premixed equivalence ratios, ϕpmx=0.14 and 0.56, are studied, representing conditions below and above the lower flammability limit (LFL) of methane. Cold flow simulations and comparison with experimental velocity data suggest that the flow field is reasonably well predicted. Combustion simulations then explore the impact of ϕpmx on flame structure, with analysis performed in both physical space and conditional scalar space of DCMC. The results show good agreement with experimental observations in terms of flame shape and reaction zone location. The findings underscore the capability of LES-DCMC to capture key features of complex, multi-modal dual-fuel combustion systems
Introduction: Themes and Knowledges (Haddenham Project Vol. 2 - Marshland communities and cultural landscapes)
Full text linkLarge-scale testing of antimicrobial lethality at single-cell resolution predicts mycobacterial infection outcomes.
Full text linkIn vitro antibiotic testing is important for guiding therapy and drug development. Current methods are focused on growth inhibition in bulk bacterial populations but often fail to accurately predict treatment responses. Here we introduce Antimicrobial Single-Cell Testing (ASCT), a large-scale live-cell imaging approach that quantifies bacterial killing in real time at single-cell resolution. By tracking over 140 million mycobacteria and analysing ~20,000 time-kill curves, we identify key determinants of antibiotic killing and its clinical relevance. For Mycobacterium tuberculosis, we found that drug-specific killing dynamics in starved bacteria, rather than growth inhibition or killing of growing cells, predict regimen efficacy in mice and humans. Extending this approach to Mycobacterium abscessus and comparing 405 bacterial strains, we show that antibiotic killing is also a genetically encoded bacterial trait (drug tolerance). We demonstrate that tolerance patterns cluster by antibiotic targets, identify a phage protein that modulates antibiotic killing, and show that strain-specific killing dynamics are associated with individual patient outcomes independent of drug resistance. Together, these findings establish a framework that reveals how drug properties and bacterial diversity shape treatment responses, offering a path to more effective and personalized therapies
Infrastructure and accessibility implications of implementing x-minute city policies in low-density contexts
Full text linkAddressing priorities such as health, liveability, and climate resilience, many global governments are exploring x-minute city and x-minute neighbourhood policies. Addressing a lack of operational models for x-minute cities, we developed a model to assess accessibility and utilisation implications of their implementation, testing the model by applying it to the low-density city of Melbourne, Australia, where 20-minute neighbourhood (20MN) policy focuses on walkable access to daily destinations within 10 minutes (20 minute round trip), and applying the model to people living within 10-minute walking distance ‘catchments’ of mixed-use activity centres. We curated a list of 14 destination types (such as supermarkets and primary schools), and developed a method to model notional placement of additional destinations to place at least 80 % of people in each catchment within a 10-minute walk of each destination type. We extended accessibility considerations to cycling, based on a 10-minute one-way ride. Our results show improvements in accessibility across the city as a whole, particularly in inner urban areas; but with significant improvements in outer urban areas, characterised by low housing density, when cycling is promoted. Our utilisation analysis demonstrates feasibility challenges when implementing x-minute city policies in less densely populated locations. Our conclusions underscore the importance of supporting x-minute city policies with safe cycling infrastructure and careful urban densification strategies. Our findings are relevant to many cities seeking to implement x-minute city or neighbourhood policies worldwide, especially cities facing challenges of low density
Twice-crossed river: Prehistoric and palaeoenvironmental investigations at Barleycroft Farm/Over, Cambridgeshire
Full text link This is the first volume charting the CAU’s on‑going Barleycroft Farm/Over investigations, which now encompasses almost twenty years of fieldwork across both banks of the River Great Ouse at its junction with the Fen. Amongst the project’s main directives is the status of a major river in prehistory – when a communication corridor and when a divide? Accordingly, a key component throughout has been the documentation of the lower Ouse’s complex palaeoenvironmental history, and a delta‑like wet landscape dotted with mid‑stream islands has been mapped.
This book is specifically concerned with the length of The Over Narrows, whose naming alludes to an extraordinary series of mid‑channel ‘river race’ ridges. With their excavation generating vast artefact sets and unique palaeo‑economic data, these ridges saw intense settlement sequences, ranging from Mesolithic camps, Grooved Ware, Beaker and Collared Urn pit clusters (plus field plots) to Middle Bronze fieldsystems and their attendant settlements, a massive Late Bronze Age midden complex and, finally, an Iron Age shrine. The latter involved extensive human bone or body‑part deposition and bird sacrifice.
Four upstanding turf barrows and two accompanying waterlogged pond barrows feature among the main excavations reported here. With more than 40 cremations (including in situ pyres), the resultant detailing of Early Bronze Age mortuary practices and the insights into the period’s monument construction are ground‑breaking.
This is an important book, for the scale of The Narrows’ excavations and palaeoenvironmental studies, its comprehensive dating programmes and, particularly, the innovative methodologies and analyses undertaken. Indeed, a commitment to experiment has lain at the project’s core. </p
280th ENMC International Workshop: The ERN EURO-NMD mitochondrial diseases working group; diagnostic criteria and outcome measures in primary mitochondrial myopathies. Hoofddorp, the Netherlands, 22-24 November 2024.
Full text linkThe 280th ENMC International Workshop, held in Hoofddorp, The Netherlands, November 22-24, 2024, focused on primary mitochondrial myopathies (PMM). The workshop aimed to update diagnostic criteria, outcome measures, and explore new digital health technologies (DHTs) in the context of clinical trial design and conduct for PMM. Key points discussed included: (i) PMM definition and phenotypes; PMM are genetically determined mitochondrial disorders with prominent skeletal muscle involvement with two major phenotypes: mitochondrial myopathy (MiMy) either with or without chronic progressive external ophthalmoplegia (PEO); (ii) diagnostic criteria, with emphasis on the importance of genetic testing and muscle biopsy for accurate diagnosis; (iii) outcome measures: consensus on clinical scales, functional tests, performance measures, and patient-reported outcome measures (PROMs) for both adults and children; (iv) digital health technologies, with exploration of wearable and non-wearable technologies for gait analysis, physical activity monitoring, and other assessments; (v) potential and limitations of biomarkers for PMM diagnosis and monitoring. The workshop concluded with a strong consensus on the updated definition of PMM, its phenotypes, and the recommended outcome measures for clinical studies. Further research is needed to validate digital health technologies and biomarkers for PMM
Typha‐based paludiculture offers potential for greater bird species abundance and diversity than drained agricultural grassland
Full text linkAbstract Agriculture on drained lowland peat, though very productive, contributes significantly to greenhouse gas (GHG) emissions. One potential solution is to implement paludiculture: an agricultural system of cropping with raised water tables. Despite the potential for reducing GHG emissions, little is known about the impact of paludiculture on biodiversity. We carried out breeding bird surveys using point counts to investigate bird habitat associations in cattail ( Typha spp.) paludiculture at 10 trial sites in the Netherlands. We also performed point counts at nine nearby natural wetland sites and nine agricultural grassland sites for comparison. We modelled the results using generalised linear mixed model and analysis of similarities to understand differences in bird abundance and community composition between these land uses. Paludiculture hosted a range of generalist and wetland specialist bird species, including several that are considered of European or global conservation concern. Predicted bird abundance in paludiculture was comparable to natural wetland (30.8 birds per ha; standard error: ±7.85; and 31.5 ± 10.5, respectively) and significantly higher than on grasslands (10.5 ± 3.23, p < 0.01). Community composition in paludiculture was between that of wetlands and grasslands. While some wetland specialists were recorded in paludiculture, they were at lower abundance than in wetlands, and not all wetland specialists were present in paludiculture. The only species present in both paludiculture and grassland were those which forage in both habitats and are considered generalists. Practical implication . Our study shows that paludiculture can support overall bird abundance on par with wetlands, and function as a habitat bridging agricultural and wetland species assemblages by providing resources for both generalist and wetland‐associated species. These results suggest that paludiculture can be a multifunctional land use, enhancing biodiversity in addition to other known benefits
The Shape of Lands – Landscape Appraisal, Palaeoenvironmental and Drainage Studies (Twice-crossed river: Prehistoric and palaeoenvironmental investigations at Barleycroft Farm/Over, Cambridgeshire)
Full text linkGender dynamics in authorship of scientific publications in obstetrics and gynaecology: a 10-year bibliometric analysis of six high-impact journals.
Full text linkOBJECTIVE: Although obstetrics and gynaecology (O&G) is a predominantly female specialty, previous studies have suggested that women remain under-represented in academic authorship. This study evaluates trends in female and male first and last authorship in six leading O&G journals (Human Reproduction Update, American Journal of Obstetrics and Gynecology, British Journal of Obstetrics and Gynaecology, Obstetrics and Gynecology, Gynecologic Oncology and Best Practice & Research Clinical Obstetrics & Gynaecology) between January 2013 and December 2023. METHODS: A bibliometric analysis was conducted using the Web of Science database. The gender of the first and last authors was determined using Genderize.io, with a probability threshold of ≥75% for classification. Binary logistic regression was performed to model the probability of authorship by gender across journals. RESULTS: Among 57 310 publications, 38 455 first (43.8% male and 56.2% female) and 38 950 last authors (58.6% male and 41.4% female) were identified and analysed. Over the past decade, female authorship has shown a clear upward trend, with first authorship increasing from 43% (1141/2636) in 2013 to 69% (2769/4036) in 2023, and last authorship increasing from 29% (770/2700) to 54% (2180/4047). First authorship was statistically more likely to be held by women in Human Reproduction Update (1.23, 95% CI 1.02 to 1.48), American Journal of Obstetrics & Gynecology (1.63, 95% CI 1.58 to 1.70) and Obstetrics & Gynecology (2.33, 95% CI 2.22 to 2.45). However, female last authorship was significantly more likely only in Obstetrics & Gynecology (1.21, 95% CI 1.16 to 1.27). CONCLUSION: Despite an increasing trend in female representation in first and last authorships over the past decade, a significant gender disparity persists. While women now constitute the majority of first authors, last authorship remains disproportionately male, reflecting ongoing barriers to female leadership in O&G research. These findings highlight the need for targeted institutional efforts to promote gender equity in academic medicine
High-spin state dynamics and quintet-mediated emission in intramolecular singlet fission
Full text linkAbstract
High-spin states in molecular systems hold significant interest for applications ranging from optoelectronics to quantum technologies. Spin states generated in intramolecular singlet fission are of particular relevance, yet the mechanisms controlling triplet-pair formation are not fully understood – especially the involvement of quintet states in luminescence at room temperature remains experimentally elusive. Here, we investigate high-spin state formation and emission in dimers and trimers comprising multiple diphenylhexatriene units. We demonstrate the formation of pure quintet states in all these oligomers, with quintet-mediated emission dominating delayed fluorescence up to room temperature. By distinguishing between the formation of weakly exchange-coupled triplet pairs and triplet excitons generated by intersystem crossing, we identify the methylated trimer as the only oligomer exhibiting exclusively the desired singlet fission route. These findings establish quintet-mediated delayed emission as a distinct spin-selective pathway and show how molecular structure directs high-spin formation, opening opportunities for room-temperature molecular quantum technologies.</jats:p