cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Musculoskeletal modelling of the shoulder during cricket bowling
Creators: name: Persad, Lomas Shiva
Publisher: name: Imperial College London
Year: 2016

description: Shoulder injuries affect athletes who participate in overhead sports, such as swimming, baseball or basketball. This is due to the high loading, large range of motion and repetitive nature of the sporting task. Impingement has been identified as the most common cause of shoulder pain in overhead athletes. Cricket bowling involves one of the more complex sporting tasks where the arm goes through a large range of motion during circumduction to project the cricket ball at varying degrees of speed and spin where injury surveillance research estimates that over 20% of cricket injuries are related to the upper limb with the glenohumeral joint being the second most injured site. Similar to other overhead athletes, cricket bowlers have a prevalence of shoulder injury and pain with loss of internal rotation. It is hypothesised that this is due to large distraction forces and muscle imbalance at the glenohumeral joint. A second, specific hypothesis is that bowlers who have greater internal rotation after delivering the cricket ball are more likely to suffer from impingement. The motivation for this study is derived from these hypotheses. The aim of this thesis was to test the hypotheses above and investigate potential shoulder injury risk in cricket bowlers. A full body 3D kinematic analysis of fast and slow bowling actions was conducted and a musculoskeletal model used to investigate joint forces and muscle activations at the shoulder. Technical advances were made in musculoskeletal modelling; these included a new kinematic optimisation routine and improvements in the muscle wrapping method. The performance of a scapula tracker in full speed bowling trials showed good repeatability. There was however, significantly greater posterior/anterior tilt and internal rotation underlining the effect of speed of movement on the scapula tracker that was used. At ball release, the glenohumeral adduction angle for fast bowlers was between 36°- 80° and 59°- 66° for slow bowlers with the humerus externally rotated within a range of 90°- 140° and 71°- 131° for both sets of bowlers respectively. The analysis showed that one potentially vulnerable position was in the region between upper arm horizontal and ball release due to the location of the joint reaction force and its magntiude. A large distraction force was reported for bowlers where the superior shear forces was also a key factor in determining the risk on injuries at the joint. Predicted activation pattern for subscapularis substantiate the risk of impingement injuries due to overuse and fatigue during rotation of the arm from upper arm horizontal to ball release. In addition, internal/external glenohumeral joint torque values were similar for both sets of bowlers with the peak value occuring midway between upper arm horizontal and ball release. Further work should concentrate on the link between technique and musculoskeletal loads and thus allow training to mitigate the risk of shoulder injury.
Stochastic Particle Acceleration near Accreting Black Holes
Creators: name: Dermer, Charles D.
name: Miller, James A.
name: Li, Hui
Publisher: name: arXiv
Year: 1995
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We consider the stochastic acceleration of particles which results from resonant interactions with plasma waves in black hole magnetospheres. We calculate acceleration rates and escape time scales for protons and electrons resonating with Alfvén waves, and for electrons resonating with whistlers. Assuming either a Kolmogorov or Kraichnan wave spectrum, accretion at the Eddington limit, magnetic field strengths near equipartition, and turbulence energy densities $\sim 10\%$ of the total magnetic field energy density, we find that Alfvén waves accelerate protons to Lorentz factors $\lte 10^4$--$10^6$ before they escape from the system. Acceleration of electrons by fast mode and whistler waves can produce a nonthermal population of relativistic electons whose maximum energy is determined by a competition with radiation losses. Particle energization and outflow is not possible at lower accretion rates, magnetic field strengths, or turbulence levels due to dominant Coulomb losses. Increases in the accretion luminosity relative to the Eddington luminosity can trigger particle acceleration out of the thermal background, and this mechanism could account for the differences between radio-quiet and radio-loud active galactic nuclei. Observations of outflowing radio-emitting components following transient X-ray events in galactic X-ray novae and gamma-ray flares in blazars are in accord with this scenario.
description: 31 pages, 8 figures, uuencoded compressed postscript file. Accepted for publication in The Astrophysical Journal (1 January 1996)
Bos bubalis Linnaeus, 1758, spec. nov.
Creators: name: Linnaeus, Carolus
Publisher: name: Laurentius Salvius
Year: 1758
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Artiodactyla
Bovidae
Bos
Bos bubalis

description: Bos bubalis [spec. nov.]
B. cornibus resupinatis intortis antice planis. Syst. nat. 15. n. 4.
Bubalus. Raj. quadr. 72. Gesn. quadr. 58. Aldr. bisulc. l. 1. c. 6.
Habitat in Asia, cultus in Italia.
Lana duriuscula in dorso, caeterum pili rari. Regitur annulo narium; trahit currus; oryzam colit; caseum di cavallo praebet.
description: Published as part of Linnaeus, Carolus, 1758, Systema Naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Stockholm :Laurentius Salvius on page 72, DOI: 10.5962/bhl.title.542, http://zenodo.org/record/3922206
Near infrared and optical morphology of the dusty galaxy NGC972
Creators: name: Mayya, Y. D.
name: Ravindranath, Swara
name: Carrasco, L.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Near infrared (NIR) and optical surface photometric analyses of the dusty galaxy NGC972 are presented. The photometric profiles in the BVRJHK bands can be fitted with a combination of gaussian and exponential profiles, corresponding to a starburst nucleus and a stellar disk respectively. The exponential scale length in the B-band is 2.8 times larger than in the K-band, which implies a central B-band optical depth as high as 11. A bulge is absent even in the NIR bands and hence the galaxy must be of a morphological type later than the usually adopted Sb type. Relatively low rotational velocity and high gas content also favor a later type, probably Sd, for the galaxy. Only one arm can be traced in the distribution of old stars; the second arm, however, can be traced in the distribution of dust and HII regions. Data suggest a short NIR bar, which ends inside the nuclear ring. The slowly rising nature of the rotation curve rules out a resonance origin of the the nuclear ring. The ring is most likely not in the plane of the galaxy, given its circular appearance in spite of the moderately high inclination of the galaxy. The off-planar nature of the star forming ring, the unusually high fraction (30%) of the total mass in molecular form, the presence of a nuclear starburst and the asymmetry of spiral arms, are probably the result of a merger with a gas-rich companion galaxy.
description: Uses aas2pp4.sty and epsfig.sty, 12 pages To appear in Astronomical Journal, October 1998
Interferometric and Uhlmann phases of mixed polarization states
Creators: name: Kiselev, Alexei D.
name: Kesaev, Vladimir V.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In our investigation into the effects of the degree of polarization in modulation of partially polarized light we assume general settings of the interferometry of partially polarized lightwaves and perform theoretical analysis of the Uhlmann and the interferometric phases. We introduce the relative Uhlmann phase determined by the Uhlmann holonomies of interfering beams and show that the interferometric phase generalized to the case of nonunitary evolution can, similar to the Uhlmann phase, be cast into the holonomy defined form. By using the technique based on a two-arm Mach-Zehnder interferometer, two different dynamical regimes of light modulation are experimentally studied: (a) modulation of the input light by the rotating quarter-wave plate (QWP); and (b) modulation of the testing beam by a birefringent plate with electrically controlled anisotropy represented by the deformed-helix ferroelectric liquid crystal (DHFLC) cell. In the setup with the rotating QWP, the interferometric phase is found to be equal to the relative Uhlmann phase. Experimental and theoretical results being in excellent agreement both show that this phase is an oscillating function of the QWP angle and increases with the degree of polarization. For modulation by the DHFLC cell, the data derived from our electro-optic measurements are fitted using the theory of the orientational Kerr effect in FLCs. This theory in combination with the results of fitting is used to evaluate electric field dependencies of the interferometric and the Uhlmann phases.
description: revtex 4.1, 19 pages, 12 figures (published version)
The Galaxy Power Spectrum and Bispectrum in Redshift Space
Creators: name: Desjacques, Vincent
name: Jeong, Donghui
name: Schmidt, Fabian
Publisher: name: arXiv
Year: 2018
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present the complete expression for the next-to-leading (1-loop) order galaxy power spectrum and the leading-order galaxy bispectrum in redshift space in the general bias expansion, or equivalently the effective field theory of biased tracers. We consistently include all line-of-sight dependent selection effects. These are degenerate with many, but not all, of the redshift-space distortion contributions, and have not been consistently derived before. Moreover, we show that, in the framework of effective field theory, a consistent bias expansion in redshift space must include these selection contributions. Physical arguments about the tracer sample considered and its observational selection have to be used to justify neglecting the selection contributions. In summary, the next-to-leading order galaxy power spectrum and leading-order galaxy bispectrum in the general bias expansion are described by 22 parameters, which reduces to 11 parameters if selection effects can be neglected. All contributions to the power spectrum can be written in terms of 28 independent loop integrals.
description: 61 pages, 2 figures. The version published in JCAP, except that the supplementary material pointing to GitHub
Low-overhead fault-tolerant logic for field-programmable gate arrays
Creators: name: Davis, James
Publisher: name: Imperial College London
Year: 2015

description: While allowing for the fabrication of increasingly complex and efficient circuitry, transistor shrinkage and count-per-device expansion have major downsides: chiefly increased variation, degradation and fault susceptibility. For this reason, design-time consideration of faults will have to be given to increasing numbers of electronic systems in the future to ensure yields, reliabilities and lifetimes remain acceptably high. Many mathematical operators commonly accelerated in hardware are suited to modification resulting in datapath error detection and correction capabilities with far lower area, performance and/or power consumption overheads than those incurred through the utilisation of more established, general-purpose fault tolerance methods such as modular redundancy. Field-programmable gate arrays are uniquely placed to allow further area savings to be made thanks to their dynamic reconfigurability. The majority of the technical work presented within this thesis is based upon a benchmark hardware accelerator---a matrix multiplier---that underwent several evolutions in order to detect and correct faults manifesting along its datapath at runtime. In the first instance, fault detectability in excess of 99% was achieved in return for 7.87% additional area and 45.5% extra latency. In the second, the ability to correct errors caused by those faults was added at the cost of 4.20% more area, while 50.7% of this---and 46.2% of the previously incurred latency overhead---was removed through the introduction of partial reconfiguration in the third. The fourth demonstrates further reductions in both area and performance overheads---of 16.7% and 8.27%, respectively---through systematic data width reduction by allowing errors of less than ±0.5% of the maximum output value to propagate.
On minimal energy states of chiral MHD turbulence
Creators: name: Pavlović, Petar
name: Sigl, Günter
Publisher: name: arXiv
Year: 2018
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We study the evolution of magnetohydrodynamic turbulence taking into account the chiral anomaly effect. This chiral magnetohydrodynamic description of the plasma is expected to be relevant for temperatures comparable to the electroweak scale, and therefore for the evolution of magnetic fields in the early Universe and young neutron stars. We focus on the case of freely decaying chiral magnetohydrodynamic turbulence and discuss the dissipation of ideal MHD invariants. Using the variational approach we discuss the minimum energy configurations of magnetic field and velocity. As in the case of the standard magnetohydrodynamic turbulence, we find that the natural relaxation state is given by a force-free field, $\nabla \times \mathbf{B} \propto \mathbf{B}$. However, the precise form of this configuration is now determined by parameters describing the chiral anomaly effect, leading to some important differences when compared to the non-chiral turbulence. Using this result we argue that the evolution of velocity and magnetic field will tend to effectively decouple during the transition to this minimal energy state.
description: 14 pages, 0 figures
Automated optimization of numerical methods for partial differential equations
Creators: name: Luporini, Fabio
Publisher: name: Imperial College London
Year: 2016

description: The time required to execute real-world scientific computations is a major issue. A single simulation may last hours, days, or even weeks to reach a certain level of accuracy, despite running on large-scale parallel architectures. Strict time limits may often be imposed too -- 60 minutes in the case of the UK Met Office to produce a forecast. In this thesis, it is demonstrated that by raising the level of abstraction, the performance of a class of numerical methods for solving partial differential equations is improvable with minimal user intervention or, in many circumstances, with no user intervention at all. The use of high level languages to express mathematical problems enables domain-specific optimization via compilers. These automated optimizations are proven to be effective in a variety of real-world applications and computational kernels. The focus is on numerical methods based on unstructured meshes, such as the finite element method. The loop nests for unstructured mesh traversal are often irregular (i.e., they perform non-affine memory accesses, such as A[B[i]]), which makes reordering transformations for data locality essentially impossible for low level compilers. Further, the computational kernels are often characterized by complex mathematical expressions, and manual optimization is simply not conceivable. We discuss algorithmic solutions to these problems and present tools for their automation. These tools -- the COFFEE compiler and the SLOPE library -- are currently in use in frameworks for solving partial differential equations.
Quantum plasmonic N00N state in a silver nanowire and its use for quantum sensing
Creators: name: Chen, Yang
name: Lee, Changhyoup
name: Lu, Liu
name: Liu, Di
name: Wu, Yunkun
name: Feng, Lantian
name: Li, Ming
name: Rockstuhl, Carsten
name: Guo, Guoping
name: Guo, Guangcan
name: Tame, Mark
name: Ren, Xifeng
Publisher: name: arXiv
Year: 2018
Subjects: subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The control of quantum states of light at the nanoscale has become possible in recent years with the use of plasmonics. Here, many types of nanophotonic devices and applications have been suggested that take advantage of quantum optical effects, despite the inherent presence of loss. A key example is quantum plasmonic sensing, which provides sensitivity beyond the classical limit using entangled N00N states and their generalizations in a compact system operating below the diffraction limit. In this work, we experimentally demonstrate the excitation and propagation of a two-plasmon entangled N00N state (N=2) in a silver nanowire, and assess the performance of our system for carrying out quantum sensing. Polarization entangled photon pairs are converted into plasmons in the silver nanowire, which propagate over a distance of 5 um and re-convert back into photons. A full analysis of the plasmonic system finds that the high-quality entanglement is preserved throughout. We measure the characteristic super-resolution phase oscillations of the entangled state via coincidence measurements. We also identify various sources of loss in our setup and show how they can be mitigated, in principle, in order to reach super-sensitivity that goes beyond the classical sensing limit. Our results show that polarization entanglement can be preserved in a plasmonic nanowire and that sensing with a quantum advantage is possible with moderate loss present.
description: 7 pages,4 figures
A Heterogeneous Sensor Suite for Reducing the Cognitive Burden of Upper Limb Robotic Control
Creators: name: Gardner, Marcus Jian Li
Publisher: name: Imperial College London
Year: 2016

description: A Human machine interface (HMI) acts like a bridge between motor function and the brain. Bypassing these natural pathways allows disabled individuals to perform actions that might otherwise be too difficult or impossible. The loss or impairment of voluntary muscle control can have a detrimental effect on an individual’s quality of life. By utilising natural physiological motion with sensor fusion techniques, grasp intention can be predicted, leading to an assistive HMI concept that can reduce the cognitive load that traditional HMIs impose on the user. This thesis investigates a novel design concept for a heterogeneous sensor suite, by fusing mechanomyogram (MMG) sensors for muscle activation, computer vision for object recognition, and inertial measurement sensors for predicting grasp intention. The developed architecture focuses on the prediction of intentional grasp activity of 1 amputee and 10 healthy subjects, using the natural physiological motion of the arm when reaching to grasp 3 objects with up to 3 different grasp patterns. 84 motion features are extracted and used as a classification tool for predicting intention, yielding an average grasp classification accuracy of 100%, 82.5% and 88.9% for bottle, lid and box objects across all subjects. The novel heterogeneous sensor suite is applied to automate the grasp control of a myoelectric hand prosthesis. Real-time task-based experiments evaluated the performance of the proposed system, comparing it against conventional control using MMG sensors, yielding an 8.5% average faster completion time, as well as a reduction in overall cognitive and physical burden. The results of this research provide excellent potential for the use of natural motion to replace discrete muscle input as a selection and intention prediction tool, where the emphasis is on reducing the cognitive load imposed by assistive technologies.
Tan's contact scaling behaviour for trapped Lieb-Liniger bosons: from two to many
Creators: name: Rizzi, Matteo
name: Miniatura, Christian
name: Minguzzi, Anna
name: Vignolo, Patrizia
Publisher: name: arXiv
Year: 2018
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We show that the contact parameter of N harmonically-trapped interacting 1D bosons at zero temperature can be analytically and accurately obtained by a simple rescaling of the exact two-boson solution, and that N-body effects can be almost factorized. The small deviations observed between our analytical results and DMRG calculations are more pronounced when the interaction energy is maximal (i.e. at intermediate interaction strengths) but they remain bounded by the large-N local-density approximation obtained from the Lieb-Liniger equation of state stemming from the Bethe Ansatz. The rescaled two-body solution is so close to the exact ones, that is possible, within a simple expression interpolating the rescaled two-boson result to the local-density, to obtain N-boson contact and ground state energy functions in very good agreement with DMRG calculations. Our results suggest a change of paradigm in the study of interacting quantum systems, giving to the contact parameter a more fundamental role than energy.
description: 7 pages, 4 figures. Revised version
Structure and Dynamics of the Coma Cluster
Creators: name: Colless, Matthew
name: Dunn, Andrew M.
Publisher: name: arXiv
Year: 1995
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We examine the structure and dynamics of the galaxies in the Coma cluster using a catalog of 552 redshifts including 243 new measurements. The velocity distribution is shown to be non-Gaussian due to structure associated with the group of galaxies around NGC4839, 40 arcmin SW of the cluster core. We apply a mixture-modelling algorithm to the galaxy sample and obtain a robust partition into two subclusters which we use to examine the system's dynamics. We find that the late-type galaxies are freely-falling into a largely virialised cluster core dominated by early types. We obtain a virial mass for the main cluster in close agreement with the estimates derived from recent X-ray data. The mass of the NGC4839 group is about 5-10% the mass of the main cluster. Assuming the main cluster and the NGC4839 group follow a linear two-body orbit, the favored solution has the two clusters lying at 74 degrees to the line of sight at a true separation of 0.8 Mpc and moving together at 1700 km/s. The cluster core shows evidence of an ongoing merger between two subclusters centered in projection on the dominant galaxies NGC4874 and NGC4889 but offset in velocity by 300 km/s and 1100 km/s respectively. Combining these results with X-ray and radio observations, and an interpretation of the presence or lack of an extended halo around the dominant galaxies, we develop a merger history for the Coma cluster.
description: To appear in Ap.J., 43 pages, Postscript of text only, see http://msowww.anu.edu.au/~colless/Preprints/coma.html for text, tables and figures
Bos indicus Linnaeus, 1758, spec. nov.
Creators: name: Linnaeus, Carolus
Publisher: name: Laurentius Salvius
Year: 1758
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Artiodactyla
Bovidae
Bos
Bos indicus

description: Bos indicus [spec. nov.]
B. cornibus aure brevioribus, dorso gibbo, juba nulla. �
Bubalus parvus indicus. Edw. av. 200. t. 200.
Habitat in China.
Utrum haec species distincta a praecedentibus, nec ne, dubito.
description: Published as part of Linnaeus, Carolus, 1758, Systema Naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Stockholm :Laurentius Salvius on page 72, DOI: 10.5962/bhl.title.542, http://zenodo.org/record/3922206
The impact of rock heterogeneity on solute spreading and mixing
Creators: name: Boon, Maartje
Publisher: name: Imperial College London
Year: 2017

description: In this thesis we have performed an experimental investigation on the impact of rock heterogeneity on solute spreading and mixing in porous rock using X-ray tomography. Furthermore, we have created a numerical model based on experimentally obtained statistical rock descriptions to investigate the impact of transport and chemical heterogeneity on reactive transport. We present a new core-flood test to characterize solute transport in 3-D natural-rock media. The test is carried out for three rocks with an increasing level of heterogeneity: Berea sandstone, Ketton carbonate and Indiana carbonate. The impact of heterogeneity on solute transport is analysed by: 1., quantifying spreading and mixing using metrics such as the transverse dispersion coefficient, the dilution index, and the scalar dissipation rate, and 2., visualizing and analysing flow structures such as meandering, flow-focusing and flow-splitting. The transverse dispersion coefficient, Dt, and the variation in Dt throughout the rock core, increases with Peclet number (Pe) and rock heterogeneity. The dilution index and scalar dissipation rate indicate that mixing is Fickian for the Berea sandstone and Ketton carbonate, but diverges for the Indiana carbonate. Heterogeneous rock features are observed to cause meandering, focusing or splitting of the plume depending on Pe. The impact of transport and chemical heterogeneity on reactive transport is investigated by modelling the injection of a HCl solution into the three rocks. The model shows that both transport and chemical heterogeneity are important and the dominating factor depends on the transport regime and reaction kinetics. The model is able to capture different dissolution regimes: compact dissolution is observed for low injection rates while the onset of wormholing and uniform dissolution is observed for the higher injection rates. The modelling results are a first indication that statistical descriptions of transport and chemical heterogeneity can improve continuum scale reactive transport modelling.
Metabolic profiling of ASS1 negative and ASS1 positive glioblastoma subtypes to identify novel targets for therapy
Creators: name: Langer, Julia
Publisher: name: Imperial College London
Year: 2016

description: Glioblastoma multiforme (GBM) are the most common and most malignant brain tumours. Despite treatment advances, average survival remains unacceptably low with 15-months, hence novel therapies are desperately needed. Cellular metabolism plays a central role in cancers. Sensitivity towards arginine-deprivation via pegylated arginine deaminase (ADI-PEG20) therapy has been identified in GBM, arresting proliferation in methylated arginino-succinate-synthetase-1 (ASS1M) and not unmethylated ASS1 (ASS1U) GBM cells. Advances of biochemical techniques and analysis have facilitated therapeutic target identification as well as biomarker discovery. Complimentary gas-chromatography coupled with mass spectrometry and 1-hydrogen nuclear-magnetic-resonance spectroscopy of in vitro GBM cells identified distinct metabolic profiles in ASS1 subtypes. Intracellular and extracellular analysis of GBM cells exposed to ADI-PEG20 treatment elucidated metabolic perturbations in the arginine, creatine, glycolytic, uridine, citric acid, thymine and glutamine pathways, induced by arginine deprivation. Transcriptional analysis of perturbed pathways elucidated differentially altered enzymatic expression in ASS1 GBM subtypes upon ADI-PEG20 treatment. Significantly modulated enzymes included transcriptional down-regulation of thymidylate synthase (TYMS) in ASS1M GBM cells, whereas ASS1U remained unaltered. Significantly altered enzymatic mRNA expression also identified modulation of glutamic pyruvate transaminase 2 (GPT2) in ASS1M cells, as well as thymidine kinase 2 (TK2) and alanine-glyoxylate aminotransferase 2 (AGXT2) in ASS1U GBM. Targeting the de novo thymine and creatine metabolic pathway, demonstrated that phytic acid (IP6) arrests proliferation in GBM cells, whereas creatine supplementation boosted proliferation. IP6 arrested proliferation in a time- and dose-dependent manner, irrespective of ASS1 status. Combining IP6 and ADI-PEG20, showed arrested proliferation was enhanced, compared to either treatment alone in ASS1M GBM cells.
ATI ID1265 - Experimental Assessment of Spark and Corona Igniters Energy Release.pdf
Creators: name: Discepoli, Gabriele
Publisher: name: figshare
Year: 2018
Subjects: subject: 90299 Automotive Engineering not elsewhere classified
subject: FOS: Mechanical engineering

description: The Radio-Frequency (RF) Corona Ignition System is an innovative and promising technology able to produce multiple streamers to ignite the fuel throughout the combustion chamber. This system, compared to a conventional spark ignition system, involves wider initial combustion volumes and allows the engine to operate in stable conditions at leaner mixtures, higher EGR dilutions, with faster burning rates and enabling advanced combustion strategies. Due to the intrinsic operating features of the RF corona ignition system, the production of a plasma generated by a high frequency electrical field, the energy released to the surrounding medium is a fundamental parameter to understand its behaviour and impact on a given air-fuel mixture. The aim of this paper is the energetic characterization of a prototype of corona igniter, called Advanced Corona Ignition System (ACIS), by measuring the pressure increase caused by the streamers in a controlled environment, a pressure based calorimeter. The ACIS results are also compared with a multiple spark discharges (MSD) ignition system based on standard Federal Mogul spark plug technology characterized by an integrated electronics capable of managing up to 17 consecutive discharges. The energy evaluation was carried out at room temperature with air at different pressure levels, up to 10 bar.
VUNet: Dynamic Scene View Synthesis for Traversability Estimation using an RGB Camera
Creators: name: Hirose, Noriaki
name: Sadeghian, Amir
name: Xia, Fei
name: Martin-Martin, Roberto
name: Savarese, Silvio
Publisher: name: arXiv
Year: 2018
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: We present VUNet, a novel view(VU) synthesis method for mobile robots in dynamic environments, and its application to the estimation of future traversability. Our method predicts future images for given virtual robot velocity commands using only RGB images at previous and current time steps. The future images result from applying two types of image changes to the previous and current images: 1) changes caused by different camera pose, and 2) changes due to the motion of the dynamic obstacles. We learn to predict these two types of changes disjointly using two novel network architectures, SNet and DNet. We combine SNet and DNet to synthesize future images that we pass to our previously presented method GONet to estimate the traversable areas around the robot. Our quantitative and qualitative evaluation indicate that our approach for view synthesis predicts accurate future images in both static and dynamic environments. We also show that these virtual images can be used to estimate future traversability correctly. We apply our view synthesis-based traversability estimation method to two applications for assisted teleoperation.
description: website: http://svl.stanford.edu/projects/vunet/
Stochastic analysis and control methods for molecular cell biology
Creators: name: Lakatos, Eszter
Publisher: name: Imperial College London
Year: 2017

description: Stochastic fluctuations in cellular processes often have a dominant role in evoking heterogeneous behaviour in otherwise identical cells. From a modelling point of view, stochastic systems require specialised techniques to analyse and provide predictions about the underlying processes. Here we approach this problem by presenting several methods for the analysis of stochastic networks in molecular biology. First, we address the problem of obtaining simulated trajectories of such systems. This task can be computationally prohibitively expensive and a range of approximation schemes have been proposed to lighten the burden. Here, we develop a set of multivariate moment closures that allow us to describe the stochastic dynamics of nonlinear systems. We use multivariate Gaussian, lognormal, and gamma closure to capture how correlations between different molecular species, induced by the reaction dynamics, interact with stochastic effects. In addition to the approximation method we also introduce our Python-based package that provides numerous tools to help non-expert users in stochastic analysis. Next, we present an approach to quickly evaluate the levels of noise in both naturally evolved and engineered biological systems. Controlling the behaviour of cells by rationally guiding processes is an overarching aim of recent research, but stochasticity proves a formidable obstacle in obtaining reliable models and designs. Here, we compute the states reachable by a stochastic system under some biologically relevant control input in cases with uncertainty about parameter values. Our algorithm provides a set of bounds on molecular dynamics at the level of population statistics that can be used for evaluating competing models and control strategies. In the third part, we introduce a formalism to study cellular decision making influenced by noise. Understanding the heterogeneity of phenotypes within a cell population is a long-time challenge in modelling, and Waddington's notion of a developmental landscape has become a powerful conceptual framework for this problem. Here, we derive quantitative potential landscapes that allow us to explore the global dynamics of the system. Using this method we study how different sources of noise and modifications in experimental conditions can induce significant changes in the landscape and the assumed cell fates. Finally, we propose a framework for model selection taking into account the inherent stochasticity of biochemistry. One of the main objectives of mathematical biology is identifying the most appropriate models and parameter values to describe known experimental results and provide predictions. Here, we develop and apply a Bayesian computational framework to identify dominant mechanisms controlling the variation of protein abundance between cell types. Using single cell expression of p53 in two cell lines, we compare the effect of transcription and protein degradation on the steady state distribution.
High harmonic generation from combined femtosecond laser fields
Creators: name: Holzner, Konstantin Benno
Publisher: name: Imperial College London
Year: 2017

description: In this thesis I introduce experiments that explore the effect of different combinations of femtosecond laser fields on the high harmonic generation (HHG) process and its ap- plications to probe ultrafast dynamics. Combining a fundamental driving field with a secondary field allows for control over the HHG process in several ways. The ionisation step of the process can be altered significantly by introducing a secondary field. The elec- tron trajectories in the continuum can be controlled and manipulated by the secondary field. Further, the secondary field can be used to drive a population transfer between different states of the cation. In a first experiment, we used the fundamental pulses in combination with copies of themselves (ω + ω experiment) to synthesise a field with a new temporal and spectral structure. Using this synthesised field to drive the HHG process results in a shift of the central frequency of the high-order harmonics. We demonstrated very fine control over the harmonic energy with a setup which is significantly simpler and more cost effective than more commonly used setups, and compatible with very high pulse energy sources. In a second experiment, the fundamental field is combined with its second harmonic (ω + 2ω experiment). The addition of the second frequency results in a harmonic spec- trum consisting of odd and even harmonics, as the symmetry of the combined generating field is broken. We observed below- and above-threshold harmonics in Kr and CO2 and investigated the effect of the secondary field on the harmonic generation as a function of the time delay between the fundamental and its second harmonic. We observed harmon- ics generated by the secondary field only, a delayed onset of some even harmonic orders depending on the delay and interesting modulations of the harmonic yield depending on the delay. This experiment served as a proof of principle for the setup used for the more demanding third experiment. The third experiment combined the fundamental with its third harmonic (ω + 3ω exper- iment). The idea of this experiment is to drive the HHG process with the fundamental field, whilst the third harmonic drives a population transfer between two cation states in CO2. If the population transfer is timed right, the recombination probability for the short and long trajectory contributions can be controlled separately. Since each trajectory rep- resents a specific ionisation and excursion time, any changes of the state of the system are encoded in the interferences between the contributions of the short and long trajecto- ries. This makes so-called quantum path interferences (QPI), interferences between the short and long trajectory contributions, a useful observable to probe femtosecond and attosecond dynamics.
Belluae Linnaeus, 1758, ord. nov.
Creators: name: Linnaeus, Carolus
Publisher: name: Laurentius Salvius
Year: 1758
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Belluae

description: Belluae [ord. nov.]
VII. BELLUA.
Dentes Primores obtuse truncati
Mammae duae inguinales.
description: Published as part of Linnaeus, Carolus, 1758, Systema Naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Stockholm :Laurentius Salvius on page 73, DOI: 10.5962/bhl.title.542, http://zenodo.org/record/3922206
SERCA2a gene therapy as an anti-arrhythmic in patients with advanced heart failure
Creators: name: Hayward, Carl
Publisher: name: Imperial College London
Year: 2016

description: Despite advances in pharmacological therapy, mortality and morbidity in heart failure remain high. Numerous underlying molecular abnormalities exist in the failing myocycte, of particular importance are those leading to deranged calcium handling. Gene therapy is an approach that can target these molecular abnormalities directly and a target that has received significant interest is sarcoplasmic (endoplasmic) reticulum calcium ATPase 2a (SERCA2a) which is down regulated in heart failure. There is laboratory and early clinical evidence that SERCA2a gene therapy mediated through adeno-associated virus serotype 1 (AAV1) can improve a number of measures of cardiac function, reduce cardiac alternans and reduce ventricular arrhythmias. T wave alternans (TWA) is a non-invasive marker of arrhythmia risk and is linked to abnormalities of calcium handling. As such, TWA may be a useful tool to assess the effect of AAV1-mediated SERCA2a gene therapy (AAV1.SERCA2a) on arrhythmia risk in a heart failure population. I conducted a number of studies in an attempt to refine the TWA technique with the aim of using TWA as an efficacy measure of AAV1.SERCA2a. The calcium upregulation by percutaneous administration of gene therapy in cardiac disease-2 (CUPID-2) study was a multi-national, multi-centre, placebo controlled randomised study recruiting 250 patients to assess if intracoronary AAV1.SERCA2a was effective at reducing heart failure hospitalisations in advanced heart failure. As a sub-study of the CUPID-2 trial I conducted the CUPID-2 arrhythmia sub-study in patients with an implantable cardioverter defibrillator (ICD). I investigated whether treatment with AAV1.SERCA2a reduced appropriate ICD therapies and separately I examined if AAV1.SERCA2a reduced TWA in those patients recruited at our site. I found that gene therapy trials are challenging to set up as a result of the number of legislative, safety and governance approvals that are required. Furthermore, gene therapy studies using AAV1 are difficult to recruit to as more than half of patients are ineligible due to the presence of neutralising antibodies to the viral vector. I found that delivering AAV1.SERCA2a could be performed safely at our site. AAV1.SERCA2a gene therapy did not reduce ICD therapy or TWA as was expected after the publication of neutral results in the main CUPID-2 trial. I found that a refinement of the TWA technique of examining multiple leads of the ECG could alter interpretation of TWA and could be tested as an approach to improve the prognostic value of TWA.
Gravitational Microlensing and the Galactic Halo
Creators: name: Gates, Evalyn I.
name: Gyuk, Geza
name: Turner, Michael S.
Publisher: name: arXiv
Year: 1995
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: By means of extensive galactic modeling we study the implications of the more than eighty microlensing events that have now been observed for the composition of the dark halo of the Galaxy, as well as for other properties of the Galaxy. We take the Galaxy to be comprised of luminous and dark disk components, a bulge, and a dark halo consisting of both MACHOs and cold dark matter with each component being described by several observationally motivated parameters. We pare down an initial model space of millions of galactic models to viable models, those which are consistent with the observational data, including rotation curve, local projected mass density, and microlensing rates toward the LMC and bulge. On the basis of a conservative, minimal set of observational constraints an all-MACHO halo cannot yet be excluded, although in most viable models of the Galaxy the halo MACHO fraction is between 0\% and 30\%, consistent with expectations for a universe whose primary component is cold dark matter. An all-MACHO halo is required to be light, and when data on the local escape velocity and satellite-galaxy proper motions, which probe the extent of the dark halo, are taken into account, models which have a high MACHO mass fraction are ruled out. We also explore the possibility that there are no MACHOs in the halo. Finally, we point out several important tests that could definitively exclude an all-MACHO e.g., optical depth for microlensing which is less than $1.5\times 10^{-7}$ toward the LMC or greater than $3\times 10^{-6}$ toward the bulge.
description: 19 pages, 13 multipart figures are available at ftp://astro.uchicago.edu/ftp/pub/astro/gyuk/
The development of gene drives for genetic control of the malaria mosquito
Creators: name: Hammond, Andrew Marc
Publisher: name: Imperial College London
Year: 2016

description: Genetic drive systems have the potential to modify entire insect populations in a few years through the super-Mendelian inheritance of a genetic trait. We describe a novel gene drive system called CRISPRh, which acts as a selfish genetic element in the malaria mosquito Anopheles gambiae. CRISPRh is a synthetic allele containing CRISPR/Cas9 endonuclease designed to specifically target and insert a copy of itself into its homologous chromosome in the germline of heterozygous individuals. Using a gene targeting approach, we identified three genes that confer recessive female sterility upon disruption. By inserting CRISPRh at each of these genes, we achieved super-Mendelian inheritance of CRISPRh alleles, ranging from 91 to 99.6% of the progeny of heterozygotes. Population modelling predicts that these high rates of transmission and a recessive knockout phenotype would enable CRISPRh alleles to spread rapidly through a wild mosquito population, causing population suppression through the generation of sterile females. We tested the potential of one CRISPRh allele to invade a caged population of naïve mosquitoes and observed an average increase from 50-76.4% over six generations, demonstrating the first gene drive designed to spread through a natural vector population. The CRISPRh constructs described here generate strong unintended fertility effects and are highly susceptible to target site resistance, making them unsuitable for malaria control. We expect that simple modifications can solve these issues and allow the development of gene drives for the suppression of mosquito populations to levels that do not support malaria transmission.
MIST: A Simple and Efficient Molecular Dynamics Abstraction Library for Integrator Development
Creators: name: Bethune, Iain
name: Banisch, Ralf
name: Breitmoser, Elena
name: Collis, Antonia B K
name: Gibb, Gordon
name: Gobbo, Gianpaolo
name: Matthews, Charles
name: Ackland, Graeme J
name: Leimkuhler, Benedict J
Publisher: name: arXiv
Year: 2018
Subjects: subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: We present MIST, the Molecular Integration Simulation Toolkit, a lightweight and efficient software library written in C++ which provides an abstract in- terface to common molecular dynamics codes, enabling rapid and portable development of new integration schemes for molecular dynamics. The initial release provides plug-in interfaces to NAMD-Lite, GROMACS and Amber, and includes several standard integration schemes, a constraint solver, tem- perature control using Langevin Dynamics, and two tempering schemes. We describe the architecture and functionality of the library and the C and For- tran APIs which can be used to interface additional MD codes to MIST. We show, for a range of test systems, that MIST introduces negligible overheads for serial, shared-memory parallel, and GPU-accelerated cases, except for Amber where the native integrators run directly on the GPU itself. As a demonstration of the capabilities of MIST, we describe a simulated tempering simulation used to study the free energy landscape of Alanine-12 in both vacuum and detailed solvent conditions.
description: Pre-print accepted for Computer Physics Communications
Nuclear-to-Disk Rotation Curves and Mass-to-Luminosity Ratio in Galaxies
Creators: name: Sofue, Yoshiaki
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: High-resolution nuclear-to-outer rotation curves for Sb, SBb, Sc, and SBc galaxies show generally a steep nuclear rise and flat rotation from the disk to halo. The high-velocity central rotation indicates massive core within bulges. Since this characteristics is common to most galaxies, the high-velocity central rotation cannot be due to a particular orientation of non-circular motion. Using these rotation curves, we derive the distributions of surface-mass density, and compare directly with observed surface-luminosity distributions. The mass-to-luminosity ratio (M/L) remains constant in the outer bulge and disk, while it increases toward the halo, indicating the massive halo. In the central region, the M/L also increases steeply toward the center, reaching by an order of magnitude greater value than the disk value, which may indicate a massive core of radius about 100 parsecs and mass of the order of E9 Msun. The core may be an object linking a bulge and a massive black hole. (Related data at http://www.ioa.s.u-tokyo.ac.jp/~sofue/)
description: 11 pages including figures