Molecular-scale remnants of the liquid-gas transition in supercritical polar fluids

An electronically coarse-grained model for water reveals a persistent vestige of the liquid-gas transition deep into the supercritical region. A crossover in the density dependence of the molecular dipole arises from the onset of non-percolating hydrogen bonds. The crossover points coincide with the Widom line in the scaling region but extend further, tracking the heat capacity maxima, offering evidence for liquid- and gas-like state points in a "one-phase" fluid. The effect is present even in dipole-limit models suggesting that it is common for all molecular liquids exhibiting dipole enhancement in the liquid phase.Comment: A Letter with Supp. Materia

Switching Cytolytic Nanopores into Antimicrobial Fractal Ruptures by a Single Side Chain Mutation

This is the author accepted manuscript. The final version is available from the American Chemical Society via the DOI in this recordDisruption of cell membranes is a fundamental host defense response found in virtually all forms of life. The molecular mechanisms vary but generally lead to energetically favored circular nanopores. Here, we report an elaborate fractal rupture pattern induced by a single side-chain mutation in ultrashort (8–11-mers) helical peptides, which otherwise form transmembrane pores. In contrast to known mechanisms, this mode of membrane disruption is restricted to the upper leaflet of the bilayer where it exhibits propagating fronts of peptide-lipid interfaces that are strikingly similar to viscous instabilities in fluid flow. The two distinct disruption modes, pores and fractal patterns, are both strongly antimicrobial, but only the fractal rupture is nonhemolytic. The results offer wide implications for elucidating differential membrane targeting phenomena defined at the nanoscale.UK Department for Business, Energy and Industrial StrategyWellcome TrustEuropean Research Council (ERC)Cambridge-NPL case studentshipWinton Programme for the Physics of SustainabilityTrinity-Henry Barlow ScholarshipMedical Research Council (MRC)Royal SocietyEngineering and Physical Sciences Research Council (EPSRC

Switching cytolytic nanopores into antimicrobial fractal ruptures by a single side chain mutation

Disruption of cell membranes is a fundamental host defense response found in virtually all forms of life. The molecular mechanisms vary but generally lead to energetically favored circular nanopores. Here, we report an elaborate fractal rupture pattern induced by a single side-chain mutation in ultrashort (8–11-mers) helical peptides, which otherwise form transmembrane pores. In contrast to known mechanisms, this mode of membrane disruption is restricted to the upper leaflet of the bilayer where it exhibits propagating fronts of peptide-lipid interfaces that are strikingly similar to viscous instabilities in fluid flow. The two distinct disruption modes, pores and fractal patterns, are both strongly antimicrobial, but only the fractal rupture is nonhemolytic. The results offer wide implications for elucidating differential membrane targeting phenomena defined at the nanoscale

The Live Creature and Ethereal Things: Physics in Culture

The Live Creature and Ethereal Things: Physics in Culture is a collection of texts, images and conversations that present fundamental physics and the physics of the universe as human activities and cultural endeavours. Cosmology and particle physics probe the furthest limits of the knowable and have the potential to provide transcendental aesthetic and conceptual experiences, enriching our everyday lives. These explorations of the otherworldly and the ethereal are undertaken by human beings in real world laboratories and observatories. Yet in our Western European culture, physics tends to be represented as factual, abstract, “hard”, and removed from our lived human experience. This lack of a sense of how physics unfolds through its processes, personalities and places leads to a gap in the cultural imaginary and social understanding of physics, which also impacts on those who might choose to study this complex subject or go into it as a profession. Featuring texts, images and conversations by physicists, artists and curators, the book examines the role of personality, power and culture in physics and discusses the value of cross-pollination between the practices of contemporary art and physics. These reflections shed light on the people and material practices of physics: from the vast underground particle physics laboratory at CERN, Geneva, used by half of the world’s particle physicists, and deep underground neutrino observatories in the UK, Italy and Antarctica, to super-computers that construct astonishing visualisations of the evolution of the universe

Virtual power plant control concepts with electric vehicles

Three approaches for grid integration of Electric Vehicles (EVs) through a Virtual Power Plant (VPP) concept are introduced. A classification of these different ways for realizing a VPP based on the control structure, resource type, and the aggregation approach is discussed. This is followed by a description of the three VPP approaches, which are referred to as direct, hierarchical, and distributed control approaches. For each of the three approaches, the necessary operational steps are discussed and the differences are highlighted. Finally, a case study is presented to demonstrate EV integration through a VPP concept