Publications by authors named "Martin Bates"

The dynamics of long term phase separation in binary liquid mixtures remains a subject of fundamental interest. Here, we study a binary liquid mixture, where the minority phase is confined to a liquid crystal (LC)-rich droplet, by investigating the evolution of size, defect and mesogen alignment over time. We track the binary liquid mixture evolving towards equilibrium by visualising the configuration of the liquid crystal droplet through polarisation microscopy.

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Role 1 doctors in the British Army work predominantly in primary healthcare, but also provide prehospital emergency care and administer potent parenteral medications in the field. Role 1 doctors have theoretical training in the use of these medications on short courses but then have little refresher training and use them infrequently in their routine practice, introducing the risk of skill fade. This may lead to higher rates of medication errors in an environment where the consequences may be significant.

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Thirteen permanent fully erupted teeth were excavated at the Paleolithic site of La Cotte de St Brelade in Jersey in 1910 and 1911. These were all found in the same location, on a ledge behind a hearth in a Mousterian occupation level. They were originally identified as being Neanderthal.

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In September 2019, Harrogate Army Foundation College (AFC) introduced what is believed to be the British Army's first smoking ban. AFC, the British Army's only training college for junior soldiers (JS) aged 16-18 years, had identified the possibility of JS adopting a smoking habit during training and introduced positive steps to mitigate this risk. The smoking ban for JS was part of a phased approach, with a complete ban being implemented in January 2020, which extended to all personnel on camp.

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The Upper Palaeolithic is characterised by the appearance of iconographic expressions most often depicting animals, including anthropomorphic forms, and geometric signs. The Late Upper Palaeolithic Magdalenian saw a flourishing of such depictions, encompassing cave art, engraving of stone, bone and antler blanks and decoration of tools and weapons. Though Magdalenian settlement exists as far northwest as Britain, there is a limited range of art known from this region, possibly associated with only fleeting occupation of Britain during this period.

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We present a Monte Carlo simulation study of chiral nematic liquid crystals confined in torus-shaped and cylindrical cavities. For an achiral nematic with planar degenerate anchoring confined to a toroidal or cylindrical cavity, the ground state is defect free, with an untwisted director field. As chirality is introduced, the ground state remains defect free but the director field becomes twisted within the cavity.

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Ionic, tetracatenar liquid crystals containing an N-phenylpyridinum core are described; many of these compounds display a SmA phase, something extremely rare in tetracatenar materials. The competing forces driving mesophase formation lead to an unprecedented difference in phase stabilities for SmA and Colh phases.

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Objectives: To record the activation and use of the Eastern Sovereign Base Area (ESBA) emergency ambulance service of British Forces Cyprus between 1 September 2013 and 31 August 2016. To reflect on these findings in light of data from 1995 to 1998 to identify current treads and areas of development.

Method: Retrospective epidemiological study of all activations of the ESBA emergency ambulance service within the study period.

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The UK prevalence of scarlet fever, a Group A streptococcal infection, is increasing. We present an unusual case of suspected recurrent scarlet fever in a member of the UK Armed Forces. Treatments, occupational implication and public health measures to mitigate the risk of disease spread.

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Unlabelled: CLINICAL INTRODUCTION: A 29-year-old keen parachutist presented to the emergency services in Cyprus complaining of sudden-onset facial flushing, dizziness and a widespread rash. The episode began on a hot day, 1 hour after she had eaten a breakfast of tinned tuna, and while she was ascending in an aircraft to parachute from 10 000 ft. She completed her jump uneventfully.

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The return to contingency after Operation HERRICK (2002-2014 Afghanistan conflict) has seen an emerging trend for small-scale rapidly developing expeditionary operations. The associated small, remote medical footprint for such operations, often within a coalition construct, reliant on host nation support is in direct conflict with the General Medical Council (GMC) guidelines for junior doctor supervision in an 'approved practice setting'. If a General Duties Medical Officer (GDMO) is nominated to support future operations, the provision of assured patient care and supervision within GMC guidelines, while ensuring career progression and ongoing education, may prove a challenge.

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We present a systematic Monte Carlo simulation study of thin nematic and cholesteric shells with planar anchoring using an off-lattice model. The results obtained using the simple model correspond with previously published results for lattice-based systems, with the number, type, and position of defects observed dependent on the shell thickness with four half-strength defects in a tetrahedral arrangement found in very thin shells and a pair of defects in a bipolar (boojum) configuration observed in thicker shells. A third intermediate defect configuration is occasionally observed for intermediate thickness shells, which is stabilized in noncentrosymmetric shells of nonuniform thickness.

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Investigations at Happisburgh, UK, have revealed the oldest known hominin footprint surface outside Africa at between ca. 1 million and 0.78 million years ago.

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We stabilize nematic droplets with handles against surface tension-driven instabilities, using a yield-stress material as outer fluid, and study the complex nematic textures and defect structures that result from the competition between topological constraints and the elasticity of the nematic liquid crystal. We uncover a surprisingly persistent twisted configuration of the nematic director inside the droplets when tangential anchoring is established at their boundaries, which we explain after considering the influence of saddle splay on the elastic free energy. For toroidal droplets, we find that the saddle-splay energy screens the twisting energy, resulting in a spontaneous breaking of mirror symmetry; the chiral twisted state persists for aspect ratios as large as ∼20.

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We study coalescence of topological defects in nematic liquid crystals confined to spherical shells using both experiments and computer simulations. We observe that the four s=+1/2 defects that are present due to topological constraints imposed by the spherical geometry coalesce by pairs after changing the molecular orientation at the outer surface from tangential to perpendicular; the result is the formation of two single s=+1 defects. It is noteworthy that the speed of the coalescence process is peaked when the defects are at opposite points on the equator of the shell; this maximum results from the thickness inhomogeneity of the shells.

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On the basis of a mechanistic understanding of the toxicity of the 4-aminoquinoline amodiaquine (1b), three series of amodiaquine analogues have been prepared where the 4-aminophenol "metabolic alert" has been modified by replacement of the 4'-hydroxy group with a hydrogen, fluorine, or chlorine atom. Following antimalarial assessment and studies on mechanism of action, two candidates were selected for detailed ADME studies and in vitro and in vivo toxicological assessment. 4'-Fluoro-N-tert-butylamodiaquine (2k) was subsequently identified as a candidate for further development studies based on potent activity versus chloroquine-sensitive and resistant parasites, moderate to excellent oral bioavailability, low toxicity in in vitro studies, and an acceptable safety profile.

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We use dissipative particle dynamics simulations to examine the phase behaviour of X-shaped quaternary bolaamphiphiles. These molecules are composed of a rod-shaped core, with polar groups at each end and two different lateral chains. We show that, as for ternary bolaamphiphiles, square and hexagonal columnar phases are observed.

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N-tert-Butyl isoquine (4) (GSK369796) is a 4-aminoquinoline drug candidate selected and developed as part of a public-private partnership between academics at Liverpool, MMV, and GSK pharmaceuticals. This molecule was rationally designed based on chemical, toxicological, pharmacokinetic, and pharmacodynamic considerations and was selected based on excellent activity against Plasmodium falciparum in vitro and rodent malaria parasites in vivo. The optimized chemistry delivered this novel synthetic quinoline in a two-step procedure from cheap and readily available starting materials.

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Monte Carlo simulations are used to map out the complete phase diagram of hard body UFO systems, in which the particles are composed of a concentric sphere and thin disk. The equation of state and phase behavior are determined for a range of relative sizes of the sphere and disk. We show that for relatively large disks, nematic and solid phases are observed in addition to the isotropic fluid.

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We examine the ordering of hard rods on the surface of a sphere using computer simulations. As predicted by previous theories of thin nematic shells we observe four s = + 1/2 defects. However, the predicted tetrahedral symmetry for the defects and the "baseball" director configuration is not observed.

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The influence of flexibility on the phase behavior of bent core biaxial nematic liquid crystals is investigated using Monte Carlo simulation. A generic model for rigid V-shaped molecules is extended to include a bending potential, which allows us to investigate the relationship between the flexibility of a bent core molecule and its ability to form a biaxial nematic phase. The simulation results indicate that, as the flexibility is increased, the biaxial nematic phase is typically forced to lower temperatures.

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Inspired by recent claims that compounds composed of V-shaped molecules can exhibit the elusive biaxial nematic phase, we have developed a generic simulation model for such systems. This contains the features of the molecule that are essential to its liquid crystal behavior, namely the anisotropies of the two arms and the angle between them. The behavior of the model has been investigated using Monte Carlo simulations for a wide range of these structural parameters.

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