28 research outputs found
Science
Monkeypox is a viral zoonotic disease endemic in Central and West Africa. In May 2022, dozens of non-endemic countries reported hundreds of monkeypox cases, most with no epidemiological link to Africa. We identified two lineages of monkeypox virus (MPXV) among two 2021 and seven 2022 US monkeypox cases: the major 2022 outbreak variant called B.1 and a minor contemporaneously sampled variant called A.2. Analyses of mutations among these two variants revealed an extreme preference for GA-to-AA mutations indicative of human APOBEC3 cytosine deaminase activity among Clade IIb MPXV (previously West African, Nigeria) sampled since 2017. Such mutations were not enriched within other MPXV clades. These findings suggest that APOBEC3 editing may be a recurrent and a dominant driver of MPXV evolution within the current outbreak.CC999999/ImCDC/Intramural CDC HHSUnited States
Deep Reinforcement Learning for Artificial Upwelling Energy Management
The potential of artificial upwelling (AU) as a means of lifting
nutrient-rich bottom water to the surface, stimulating seaweed growth, and
consequently enhancing ocean carbon sequestration, has been gaining increasing
attention in recent years. This has led to the development of the first
solar-powered and air-lifted AU system (AUS) in China. However, efficient
scheduling of air injection systems remains a crucial challenge in operating
AUS, as it holds the potential to significantly improve system efficiency.
Conventional approaches based on rules or models are often impractical due to
the complex and heterogeneous nature of the marine environment and its
associated disturbances. To address this challenge, we propose a novel energy
management approach that utilizes deep reinforcement learning (DRL) algorithm
to develop efficient strategies for operating AUS. Through extensive
simulations, we evaluate the performance of our algorithm and demonstrate its
superior effectiveness over traditional rule-based approaches and other DRL
algorithms in reducing energy wastage while ensuring the stable and efficient
operation of AUS. Our findings suggest that a DRL-based approach offers a
promising way for improving the efficiency of AUS and enhancing the
sustainability of seaweed cultivation and carbon sequestration in the ocean.Comment: 31 pages, 13 figure
Assessing fire frequency and structural fire behaviour of England statistics according to BS PD 7974-7
Contemporary structural fire statistics are fundamental in engineering design practice to evaluate likelihood and consequence of fire for different property types, and to investigate how different safety measures impact fire spread. British Standard PD 7974-7:2003 has recently been updated using USA fire statistics; this paper compares PD 7974-7:2003 to current England statistics (named UK statistics) using one public and one Home Office dataset. PD 7974-7:2003 overestimates fire frequency with values up to 5 times greater than the ones found in UK and USA. When fire frequency is plotted against total floor space, for different property types, power laws with positive or negative exponent and polynomial functions provide better approximations of the data than the current codes. Average area damage from PD 7974-7:2003 has been compared to fire and total damage from UK datasets where fire size is usually well confined to room of origin at 20% of fires based on the publicly available dataset. When fires exceeding specific areas of damage are considered, PD 7974-7:2003 usually overestimates fire damage and underestimates total damage, with more damage evident when sprinklers are absent compared to when they are present