Publications by authors named "J Willman"

Large-scale atomistic molecular dynamics (MD) simulations provide an exceptional opportunity to advance the fundamental understanding of carbon under extreme conditions of high pressures and temperatures. However, the fidelity of these simulations depends heavily on the accuracy of classical interatomic potentials governing the dynamics of many-atom systems. This study critically assesses several popular empirical potentials for carbon, as well as machine learning interatomic potentials (MLIPs), in their ability to simulate a range of physical properties at high pressures and temperatures, including the diamond equation of state, its melting line, shock Hugoniot, uniaxial compressions, and the structure of liquid carbon.

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During the early development of archaeology in Spain, many of the materials obtained from excavations were later forgotten in museum deposits. However, re-investigation of these collections with contemporary methodologies can still contribute valuable knowledge. This study presents the case of El Bosquet Cave (Mont-ral, Tarragona, Spain), located in the Northeastern Iberian Peninsula.

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We present an Atomic Cluster Expansion (ACE) machine learned potential developed for high-fidelity atomistic simulations of hydrocarbons, targeting pressures and temperatures near and above supercritical fluid regimes for molecular fluids. A diverse set of stoichiometries were covered in training, including 1:0 (pure carbon), 1:4 (methane), and 1:1 (benzene), and rich bonding environments sampled at supercritical temperatures, hydrogen rich, reactive mixtures where metastable stoichiometries arise, including 1:2 (ethylene) and 1:3 (ethane). A high-fidelity training database was constructed by performing large-scale quantum molecular dynamic simulations [density functional theory (DFT) MD] of diamond, graphite, methane, and benzene.

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We propose that domestication is the result of interspecies cooperative breeding. Considering domestication as an outcome of cooperative breeding can explain how domestication occurs in both plants and animals, encompass cases of domestication that do not involve humans, and shed light on why humans are involved in so many domesticatory relationships. We review the cooperative breeding model of human evolution, which posits that care of human infants by alloparents enabled the evolution of costly human brains and long juvenile development, while selecting for tolerance of strangers.

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Contrast-induced encephalopathy (CIE) is a rare complication of imaging using ionidated contrast media. Its pathogenesis remains unknown, and its clinical presentation is variable. We present two cases of CIE following coronary angiography (CAG) that underscore the multitude of clinical manifestations and imaging findings associated with the disorder.

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