cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Interactions between Neisseria meningitidis and galectin-3
Creators: name: Quattroni, Paola
Publisher: name: Imperial College London
Year: 2012

description: Galectins are beta-galactoside animal lectins which possess similar carbohydrate recognition domains and have important roles in the development and regulation of innate and adaptive immunity. Galectins have been previously shown to modulate inflammatory responses to bacterial infections, however nothing is known about the functions of different galectins during meningococcal disease. Here I describe the interaction between galectins, in particular galectin-3, and Neisseria meningitidis, a commensal of the human respiratory tract that occasionally causes septicaemia and meningitis. Immunohistochemical analyses showed that expression of galectin-3, but not galectin-1 and galectin-8, is increased in tissues of mice following challenge with N. meningitidis; furthermore, galectin-3 staining co-localises with the bacterium in tissues from patients with meningococcal disease. The molecular basis of interaction between N. meningitidis and exogenous galectin-3 was investigated by identifying both the bacterial structures and the regions of galectin-3 involved. Binding of galectin-3 to N. meningitidis was shown to be dependent on bacterial lipopolysaccharide (LPS), while inhibition assays with lactose and the use of truncated versions of galectin-3 demonstrated that the C-terminal carbohydrate recognition domain is necessary, but not sufficient, for the interaction. Furthermore, the biological consequences of interaction of bacteria with galectin-3 were investigated. Exogenous galectin-3 did not affect adhesion of N. meningitidis to epithelial cells, but increased the attachment of bacteria to phagocytic cells; silencing of galectin-3 expression in phagocytes did not alter the interaction of N. meningitidis with cells. In summary, galectin-3 binds to N. meningitidis via LPS and affects meningococcal interaction with phagocytic cells. The potential role of galectin-3 in pathogen recognition is discussed.
Parallelized Solution Method of the Three-dimensional Gravitational Potential on the Yin-Yang Grid
Creators: name: Almanstoetter, Marius
name: Melson, Tobias
name: Janka, H. -Thomas
name: Mueller, Ewald
Publisher: name: arXiv
Year: 2018
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: We present a new method for solving the three-dimensional gravitational potential of a density field on the Yin-Yang grid. Our algorithm is based on a multipole decomposition and completely symmetric with respect to the two Yin-Yang grid patches. It is particularly efficient on distributed-memory machines with a large number of compute tasks, because the amount of data being explicitly communicated is minimized. All operations are performed on the original grid without the need for interpolating data onto an auxiliary spherical mesh.
description: 8 pages, 4 figures; two minor additions after refereeing; accepted by ApJ
Disformal gravity
Creators: name: Noller, Johannes Joachimov
Publisher: name: Imperial College London
Year: 2012

description: An intriguing feature of scalar-tensor theories is the emergence of different metrics, e.g. when matter is minimally coupled to a metric non-trivially related to the Einstein metric g[mu,nu] used to construct the Ricci scalar. Strong equivalence principle constraints then typically force permissible “many-metric” scenarios to reduce to a bimetric picture. In this thesis we first aim to construct the most general bimetric relation, where the two metrics are related by a single scalar degree of freedom [phi] and its derivatives. This results in the disformal metric relation and a natural extension which we present. In the context of primordial structure formation, disformal bimetric theories give rise to “general single field inflation” models of the P(X, [phi]) type. We investigate the perturbative properties of such disformally motivated models. The focus is on non-Gaussian phenomenology and we establish non-Gaussian fingerprints for inflationary single field models and non-inflationary bimetric setups, also going beyond the slow-roll approximation. Furthermore we show that various dualities exist between disformally motivated P(X, [phi]) theories and higher-form models. As an explicit example we use the dual picture to compute non-Gaussian signals for three-form theories. In the context of dark energy/modified gravity, we show that the conformal subgroup of the general disformal relation can be used to construct a generalized “derivative” Chameleon setup. We present and investigate this setup and study its phenomenology. Finally we show that a natural extension of the disformal relation can generate Galileon solutions from a single geometrical invariant - the first Lovelock term - in four dimensions. As such the over-arching theme of this thesis is to show that the disformal bimetric picture and its extensions present us with a geometrical understanding of scalar-tensor/single field models. That they provide a unified description of large classes of scenarios linked to accelerated space-time expansion and also point us towards new physically motivated setups.
Parity games : descriptive complexity and algorithms for new solvers
Creators: name: Kuo, Huan-Pu
Publisher: name: Imperial College London
Year: 2013

description: Parity games are 2-person, 0-sum, graph-based, and determined games that form an important foundational concept in formal methods (see e.g., [Zie98]), and their exact computational complexity has been an open problem for over twenty years now. In this thesis, we study algorithms that solve parity games in that they determine which nodes are won by which player, and where such decisions are supported with winning strategies. We modify and so improve a known algorithm but also propose new algorithmic approaches to solving parity games and to understanding their descriptive complexity. For all of our contributions, we write our own custom frameworks, in the Scala programming language, to perform tailored experiments and empirical studies to demonstrate and support our theoretical findings. First, we improve on one of the solver algorithms, based on small progress measures [Jur00], by use of concurrency. We show that, for many parity games, it is possible to deliver extra performance using this technique in a multi-core environment. Second, we design algorithms to reduce the computational complexity of parity games, and create implementations to observe and evaluate the behaviours of these reductions in our experimental settings. The measure Rabin index, arising from the design of the said algorithm, is shown to be a new descriptive complexity for parity games. Finally, we define a new family of attractors and derive new parity game solvers from them. Although these new solvers are “partial”, in that they do not solve all parity games completely, our experiments show that they do solve a set of benchmark games (i.e., games with known structures) designed to stress test solvers from PGSolver toolkit [FL10] completely, and some of these partial solvers deliver favourable performance against a known high performance solver in many circumstances.
Cosmology in the Next Millennium: Combining MAP and SDSS Data to Constrain Inflationary Models
Creators: name: Wang, Yun
name: Spergel, David N.
name: Strauss, Michael A.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The basic cosmological parameters and the primordial power spectrum together completely specify predictions for the cosmic microwave background radiation anisotropy and large scale structure. Here we show how we can strongly constrain both $A_S^2(k)$ and the cosmological parameters by combining the data from the Microwave Anisotropy Probe (MAP) and the galaxy redshift survey from the Sloan Digital Sky Survey (SDSS). We allow $A_S^2(k)$ to be a free function, and thus probe features in the primordial power spectrum on all scales. The primordial power spectrum in 20 steps in $\log k$ to $k\leq 0.5h$Mpc$^{-1}$ can be determined to $\sim 16%$ accuracy for $k\sim 0.01h$Mpc$^{-1}$, and to $\sim 1%$ accuracy for $k\sim 0.1h$Mpc$^{-1}$. The uncertainty in the primordial power spectrum increases by a factor up to 3 on small scales if we solve simultaneously for the dimensionless Hubble constant $h$, the cosmological constant $Λ$, the baryon fraction $Ω_b$, the reionization optical depth $τ_{ri}$, and the effective bias between the matter density field and the redshift space galaxy density field $b_{\it eff}$. Alternately, if we restrict $A_S^2(k)$ to be a power law, we find that inclusion of the SDSS data breaks the degeneracy between the amplitude of the power spectrum and the optical depth inherent in the MAP data, significantly reduces the uncertainties in the determination of the matter density and the cosmological constant, and allows a determination of the galaxy bias parameter. Thus, combining the MAP and SDSS data allows the independent measurement of important cosmological parameters, and a measurement of the primordial power spectrum independent of inflationary models, giving us valuable information on physics in the early Universe, and providing clues to the correct inflationary model.
description: Substantial revisions to quantitative results as a result of more accurate calculation of derivatives; these new numerical results strengthen but do not change our qualitative results. Minor changes in wording. Several references added. Final version, to appear in ApJ January 1, 1999 issue, Vol. 510 #1
MOESM1 of Identification of Matrix Metalloproteinase-12 as a Candidate Molecule for Prevention and Treatment of Cardiometabolic Disease
Creators: name: Amor, Melina
name: Moreno-Viedma, Veronica
name: Alisina Sarabi
name: GrĂźn, Nicole
name: Itariu, Bianca
name: Leitner, Lukas
name: Steiner, Irene
name: Bilban, Martin
name: Kodama, Keiichi
name: Butte, Atul
name: Guenther Staffler
name: Zeyda, Maximilian
name: Stulnig, Thomas
Publisher: name: figshare
Year: 2016
Subjects: subject: Biochemistry
subject: 29999 Physical Sciences not elsewhere classified
subject: FOS: Physical sciences
subject: Medicine
subject: Cell Biology
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Sociology
subject: FOS: Sociology
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: Cancer
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: 60506 Virology
subject: FOS: Biological sciences

description: Identification of Matrix Metalloproteinase-12 as a Candidate Molecule for Prevention and Treatment of Cardiometabolic Disease
q-Deformed Conformal Quantum Mechanics
Creators: name: Youm, Donam
Publisher: name: arXiv
Year: 2000
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct a q-deformed version of the conformal quantum mechanics model of de Alfaro, Fubini and Furlan for which the deformation parameter is complex and the unitary time evolution of the system is preserved. We also study differential calculus on the q-deformed quantum phase space associated with such system.
description: 10 pages, LaTeX, revised version with minor corrections to appear in Phys. Rev. D
Nanocapsules via Layer-by-Layer self-assembly technique
Creators: name: Li, Ye
Publisher: name: Imperial College London
Year: 2011

description: Since the drug molecules inside human body (in the blood vessel) are recognised as being alien, and quickly eliminated or degraded, it is necessary to find a way to protect and direct these effective components to the target zone. Therefore, the design and preparation of the therapeutic delivery systems in vivo has attracted considerable attention in recent decades. Nanocapsules, as a relatively new delivery approach, have many advantages. Compared with micron or larger delivery systems, nanocapsules are smaller and hence can migrate to diseased organs without blocking the bloody vessels. Also unlike nanospheres, nanocapsules could provide more capacity space for the therapeutics loading. Therefore, in this thesis the design and preparation of nanocapsules for the drug delivery system is discussed. A Layer-by-Layer self-assembly method onto nanospheres as a template has been developed. This method allows easy control of the size of the capsules and the thickness of the capsule walls; moreover, its flexibility has enabled various types of materials to be used to form the walls of the capsules, such as polyelectrolytes, proteins and various inorganic particles. In this project, two different core templates (silica and polystyrene nanoparticles) were prepared. Hollow capsules based on silica nanoparticles (95 nm and 114 nm) were obtained from the deposition of 9 layers of Chitosan (CHI) and Dextran sulphate sodium salt (DS), subsequently the silica cores were removed by dissolving in an HF/NH4F buffer solution. For the nanocapsules based on polystyrene particles (130 nm and 480 nm), a layer of the synthetic inorganic clay, Laponite, was introduced to improve the strength of the nanocapsules. After the core-removal process (by dissolving in tetrahydrofuran THF), a high productivity of hollow nanocapsules was observed for both particle sizes. Gold (4-10 nm) and magnetite (10 nm) nanoparticles were also incorporated into the capsule walls to modify the properties of nanocapsules obtained from the polystyrene nanoparticles of 130 nm; these materials make the particles sensitive to near infer red light and a magnetic field respectively. Furthermore, nanocapsules consisting of proteins (lysozyme and bovine serum albumin BSA) and polyelectrolytes (Poly(diallydimethylammonium chloride) PDADMAC and DS) were also fabricated. In the final part of the thesis, loading materials into the nanocapsules were tried. Instead of directly loading into the nanocapsules, the insulin was first prepared as insulin nanoparticles and these nanoparticles were then coated with the polyelectrolyte/protein layers to form the nanocapsules loaded with drug molecules. This project has extended the size range of nanocapsules that can be synthesized, and also the range of materials, and hence the properties, that can be included in the walls of the nanocapsules.
Solitonic Strings and BPS Saturated Dyonic Black Holes
Creators: name: Cvetic, Mirjam
name: Tseytlin, Arkady A.
Publisher: name: arXiv
Year: 1995
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider a six-dimensional solitonic string solution described by a conformal chiral null model with non-trivial $N=4$ superconformal transverse part. It can be interpreted as a five-dimensional dyonic solitonic string wound around a compact fifth dimension. The conformal model is regular with the short-distance (`throat') region equivalent to a WZW theory. At distances larger than the compactification scale the solitonic string reduces to a dyonic static spherically-symmetric black hole of toroidally compactified heterotic string. The new four-dimensional solution is parameterised by five charges, saturates the Bogomol'nyi bound and has nontrivial dilaton-axion field and moduli fields of two-torus. When acted by combined T- and S-duality transformations it serves as a generating solution for all the static spherically-symmetric BPS-saturated configurations of the low-energy heterotic string theory compactified on six-torus. Solutions with regular horizons have the global space-time structure of extreme Reissner-Nordstrom black holes with the non-zero thermodynamic entropy which depends only on conserved (quantised) charge vectors. The independence of the thermodynamic entropy on moduli and axion-dilaton couplings strongly suggests that it should have a microscopic interpretation as counting degeneracy of underlying string configurations. This interpretation is supported by arguments based on the corresponding six-dimensional conformal field theory. The expression for the level of the WZW theory describing the throat region implies a renormalisation of the string tension by a product of magnetic charges, thus relating the entropy and the number of oscillations of the solitonic string in compact directions.
description: 27 Pages, uses RevTeX (solution for the axion field corrected, erratum to appear in Phys. Rev. D)
Disk Instabilities and Cooling Fronts
Creators: name: Vishniac, Ethan T.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Accretion disk outbursts, and their subsequent decline, offer a unique opportunity to constrain the physics of angular momentum transport in hot accretion disks. Recent work has centered on the claim by Cannizzo et al. that the exponential decay of luminosity following an outburst in black hole accretion disk systems is only consistent with a particular form for the dimensionless viscosity, $α=35(c_s/rΩ)^{3/2}$. This result can be understood in terms of a simple model of the evolution of cooling fronts in accretion disks. In particular, the cooling front speed during decline is $\sim α_F c_{s,F}(c_{s,F}/rΩ)^{n}$, where $F$ denotes the position of the cooling front, and the exact value of $n$ depends on the hot state opacity, (although generally $n\approx 1/2$). Setting this speed proportional to $r$ constrains the functional form of $α$ in the hot phase of the disk, which sets it apart from previous arguments based on the relative durations of outburst and quiescence. However, it remains uncertain how well we know the exponent $n$. In addition, more work is needed to clarify the role of irradiation in these systems and its effect on the cooling front evolution.
description: 10 pages, uses aipproc.sty
ShuffleBench: A Benchmark for Large-Scale Data Shuffling Operations with Distributed Stream Processing Frameworks
Creators: name: Henning, Sören
name: Vogel, Adriano
name: Leichtfried, Michael
name: Ertl, Otmar
name: Rabiser, Rick
Publisher: name: arXiv
Year: 2024
Subjects: subject: Software Engineering (cs.SE)
subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: Distributed stream processing frameworks help building scalable and reliable applications that perform transformations and aggregations on continuous data streams. This paper introduces ShuffleBench, a novel benchmark to evaluate the performance of modern stream processing frameworks. In contrast to other benchmarks, it focuses on use cases where stream processing frameworks are mainly employed for shuffling (i.e., re-distributing) data records to perform state-local aggregations, while the actual aggregation logic is considered as black-box software components. ShuffleBench is inspired by requirements for near real-time analytics of a large cloud observability platform and takes up benchmarking metrics and methods for latency, throughput, and scalability established in the performance engineering research community. Although inspired by a real-world observability use case, it is highly configurable to allow domain-independent evaluations. ShuffleBench comes as a ready-to-use open-source software utilizing existing Kubernetes tooling and providing implementations for four state-of-the-art frameworks. Therefore, we expect ShuffleBench to be a valuable contribution to both industrial practitioners building stream processing applications and researchers working on new stream processing approaches. We complement this paper with an experimental performance evaluation that employs ShuffleBench with various configurations on Flink, Hazelcast, Kafka Streams, and Spark in a cloud-native environment. Our results show that Flink achieves the highest throughput while Hazelcast processes data streams with the lowest latency.
description: accepted for publication in Proceedings of the 15th ACM/SPEC International Conference on Performance Engineering (ICPE '24), May 7--11, 2024, London, United Kingdom, 12 pages
Local BRS Transformations and Osp(3,1|2) Symmetry of Yang-Mills Theories
Creators: name: Joglekar, Satish D.
name: Mandal, Bhabani Prasad
Publisher: name: arXiv
Year: 1995
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider a certain local generalization of BRS transformations of Yang-Mills theory in which the anti-commuting parameter is space time dependent. While these are not exact symmetries, they do lead to a new nontrivial WT identity. We make a precise connection between the ``local BRS "and the broken orthosymplectic symmetry recently found in superspace formulation of Yang-Mills theory by showing that the local BRS WT identity is precisely the WT identity obtained in the superspace formulation via a superrotation. This ``local BRS " WT identity could lead to new consequences not contained in the usual BRS WT identity.
description: Revtex file, 14 pages , no figures
The K-band luminosity function at z=1: a powerful constraint on galaxy formation theory
Creators: name: Kauffmann, Guinevere
name: Charlot, Stephane
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: There are two major approaches to modelling galaxy evolution. The traditional view is that the most massive galaxies were assembled early and have evolved with steeply declining star formation rates since a redshift of 2 or higher. According to hierarchical theories, massive galaxies were assembled much more recently from mergers of smaller subunits. Here we present a simple observational test designed to differentiate between the two. The observed K-band flux from a galaxy is a good measure of its stellar mass even at high redshift. It is probably only weakly affected by dust extinction. We compute the evolution of the observed K-band luminosity function for traditional, pure luminosity evolution (PLE) models and for hierarchical models. At z=0, both models can fit the observed local K-band luminosity function. By redshift 1, they differ greatly in the predicted abundance of bright galaxies. We calculate the redshift distributions of K-band selected galaxies and compare these with available data. We show that the number of K<19 galaxies with redshifts greater than 1 is well below the numbers predicted by the PLE models. In the Songaila et al (1994) redshift sample of 118 galaxies with 161. Only 2 are observed. In the Cowie et al. (1996) redshift sample of 52 galaxies with 181. Only 5 are observed. Both these samples are more than 90% complete. We conclude that there is already strong evidence that the abundance of massive galaxies at z=1 is well below the local value. This is inconsistent with the traditional model, but similar to the expectations of hierarchical models.
description: 13 pages, Latex, 4 figures included in text, submitted to MNRAS pink pages
Novel descriptive and model based statistical approaches in immunology and signal transduction
Creators: name: Liepe, Juliane
Publisher: name: Imperial College London
Year: 2013

description: Biological systems are usually complex nonlinear systems of which we only have a limited understanding. Here we show three different aspects of investigating such systems. We present a method to extract detailed knowledge from typical biological trajectory data, which have randomness as a main characteristic. The migration of immune cells, such as leukocytes, are a key example of our study. The application of our methodology leads to the discovery of novel random walk behaviour of leukocyte migration. Furthermore we use the gathered knowledge to construct the under- lying mathematical model that captures the behaviour of leukocytes, or more precisely macrophages and neutrophils, under acute injury. Any model of a biological system has little predictive power if it is not compared to collected data. We present a pipeline of how complex spatio- temporal trajectory data can be used to calibrate our model of leukocyte migration. The pipeline employs approximate methods in a Bayesian framework. Using the same approach we are able to learn additional information about the underlying signalling network, which is not directly apparent in the cell migration data. While these two methods can be seen as data processing and analysis, we show in the last part of this work how to assess the information content of experiments. The choice of an experiment with the highest information content out of a set of possible experiments leads us to the problem of optimal experimental design. We develop and implement an algorithm for simulation based Bayesian experimental design in order to learn parameters of a given model. We validate our algorithm with the help of toy examples and apply it to examples in immunology (Hes1 transcription regulation) and signal transduction (growth factor induced MAPK pathway).
Optimal power series expansions of the Kohn-Sham potential
Creators: name: Callow, Timothy J.
name: Gidopoulos, Nikitas I.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: A fundamental weakness of density functional theory (DFT) is the difficulty in making systematic improvements to approximations for the exchange and correlation functionals. In this paper, we follow a wave-function-based approach [N.I. Gidopoulos, Phys. Rev. A, 83, 040502 (2011)] to develop perturbative expansions of the Kohn-Sham (KS) potential. Our method is not impeded by the problem of variational collapse of the second-order correlation energy functional. Arguing physically that a small magnitude of the correlation energy implies weak perturbation and hence fast convergence of the perturbative expansion for the interacting state and for the KS potential, we discuss several choices for the zeroth-order Hamiltonian in such expansions. Our first two choices yield KS potentials containing only Hartree and exchange terms: the exchange-only optimized effective potential (xOEP), also known as the exact-exchange potential (EXX), and the Local Fock exchange (LFX) potential. Finally, we choose the zeroth order Hamiltonian that corresponds to minimum magnitude of the second order correlation energy, aiming to obtain at first order the most accurate approximation for the KS potential with Hartree, exchange and correlation character.
title: Employability: what is it and is it important?
Creators: name: Creighton, Matthew
Publisher: name: University of Glasgow
Year: 2007
Subjects: subject: Labor relations, employability.

description: This thesis examines and reaches conclusions about the nature and significance of employability, in relation to unemployed and disadvantaged groups. It establishes that despite the importance attached to the concept there is no consensus as to its meaning; that while for individuals it necessarily impacts on their employment outcomes, there is little consensus as to its significance for the working of labour markets and that the factors which may contribute to it occupy a wide spectrum. Different definitions can be mapped on this spectrum, which covers all of the characteristics of individuals, on the supply side of the labour market; and in some cases, aspects of the demand side as well. Having looked at the history of the term and the UK policy context, five strands of thought are derived. The most significant contrast is between narrow definitions focusing on the minimum characteristics needed to be able to work ('job-ready') and wide ones which encompass all of the factors which determine job entry outcomes. The thesis proceeds by examining labour market theory and empirical studies for what they can contribute to this enquiry. In both cases it is found that neither makes any substantial use of the term. However insights available from them are applied to consideration of the merits of different meanings of employability, and of its significance. The penultimate chapter reports a survey about the uses of the term by practitioners and policy-makers in Edinburgh and Glasgow; the meanings given to it; the factors thought to be important for the employability of jobseekers; and questions related to the services which they provided. This confirms the confusion associated with the meaning of the term but also indicates that in practice aspects of the demand side have little place in common usage. It also reveals that the most commonly-cited employability problems are self- confidence/self-esteem; and motivation/attitude. This contrasts with the balance implied in the definitions in the literature. In the final chapter conclusions are drawn which favour the narrow definitions, and draw attention to the issues revealed by the survey about self- confidence and motivation. They recognise however that the term will continue to be used in a variety of ways.
The Role of monitoring in the integrated management of surface water bodies: recommendations for the implementation of the water framework directive
Creators: name: Collins, Alexandra
Publisher: name: Imperial College London
Year: 2013

description: The collection of data though environmental monitoring is critical to the success of integrated water management, therefore this PhD investigated its role in the management of surface water bodies, providing recommendations for the implementation of the Water Framework Directive (WFD). The monitoring requirements of the WFD have been reviewed and a comparison to previous arrangements in England and Wales was made. Findings demonstrated the challenges associated with a transition from established networks to those that support more integrated approaches. Using a river basin in England the role of monitoring in both ecological and chemical assessments was evaluated. Results revealed the need to evaluate data produced and ensure that networks are risk based and adaptive, both responding to and aiding understanding of the processes that determine water quality. The need to supplement regulatory monitoring with technical analyses to understand source-pathways-receptor models for contaminants, along with the need to combine chemical and biological assessments so that the risks to ecosystems can be identified was highlighted. The use of data to enable the identification and management of the pressures on surface water bodies was then explored. It was demonstrated that a systems approach to understanding the interactions between the abiotic, biotic and functioning of the ecosystem was needed so that pressures could be managed sustainably. The need to monitor the effectiveness of measures implemented to improve water bodies was also highlighted, with examples of both the structural and functional elements that could be used provided. Finally, recommendations on the communicating of data to stakeholders, along with their involvement in the management and monitoring of water bodies, were made. This work highlights the potential role monitoring has in the successful implementation of the WFD, demonstrating the need for review and flexibility in monitoring networks, along with frameworks which enable monitoring to contribute to understanding of ecosystems and allow collaboration and knowledge sharing within decision making processes.
Are He and N Abundances in Type I PNe as High as Empirically Derived?
Creators: name: Gruenwald, Ruth
name: Viegas, Sueli M.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Type I planetary nebulae (PNe) are defined as those with high He and N abundances (Peimbert & Torres-Peimbert 1983). These objects present in general bipolar geometries and have high stellar temperatures (Corradi & Schwarz 1995, Torres-Peimbert & Peimbert 1997). In this paper we analyse the empirical methods for abundance determination in order to check if the He and N overabundances in Type I PNe are a consequence of a geometrical effect, due to the bipolarity, or the ionization stratification, due to the stellar temperature. For this, we obtain simulated spherically symmetrical as well as bipolar nebulae, using a 3D photoionization code. From the projected emission line intensities for: a) the whole nebula; b) for a slit crossing the nebula; as well as c) for different positions in the nebula, we applied the formulae used in the literature to obtain empirical abundances. These empirical abundances are then compared with the adopted ones. We show that empirical abundances depend on the particular line of sight covered by the observation and can simulate an overabundance and/or the presence of abundance gradients of He and N in planetary nebulae with high stellar temperature. The geometrical effects are also discussed. Systematic errors in abundance determinations by empirical methods are higher for the N/H ratio than for N/O. Thus, it seems better to use the N/O value when discussing N rich objects.
description: 19 pages, 5 figures, aastex package, to be published at Ap.J
Exploring the Early Universe with Gravitational Waves
Creators: name: Bethke, Laura Bianca
Publisher: name: Imperial College London
Year: 2014

description: In this thesis, I will discuss two separate topics which are related to gravitational wave production in the early universe. The first part will focus on the tensor power spectrum from inflation, derived using the Ashtekar variables of loop quantum gravity. This formalism is different from the ordinary approach in that it uses a complex connection as the central gravitational variable instead of the metric. Although the choice of variables should not affect any classical results, it becomes vital when considering quantum mechanical quantities like vacuum fluctuations. We will find that in this formalism, the tensor power spectrum is chiral, which would lead to a non-zero TB correlator in the CMB. Obtaining the full TB power spectrum would enable us to probe this chirality and provide clues about the nature of gravity. In the second part, I will consider gravitational waves produced from massless preheating, during which the inflaton transfers energy to a scalar field chi. If chi is light, it acquires a scale invariant spectrum of perturbations from inflation. At the time of preheating, the field will therefore have fluctuations on superhorizon scales and take a different value in different parts of the observable universe. I will study GW production for different initial values of chi numerically using 3d lattice simulations. The GW amplitude strongly depends on this initial value, leading to a GW background that is anisotropic today, with relative fluctuations of order 1%. In general, anisotropies will occur in any model of preheating with a light scalar field, and the characteristics should strongly depend on the model parameters. If a GW background from preheating was measured in the future, it would provide a novel way to distinguish between different inflationary scenarios.
Magnetic monopoles vs. Hopf defects in the Laplacian (Abelian) gauge
Creators: name: Bruckmann, F.
name: Heinzl, T.
name: Vekua, T.
name: Wipf, A.
Publisher: name: arXiv
Year: 2000
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We investigate the Laplacian Abelian gauge on the sphere S^4 in the background of a single `t Hooft instanton. To this end we solve the eigenvalue problem of the covariant Laplace operator in the adjoint representation. The ground state wave function serves as an auxiliary Higgs field. We find that the ground state is always degenerate and has nodes. Upon diagonalisation, these zeros induce toplogical defects in the gauge potentials. The nature of the defects crucially depends on the order of the zeros. For first-order zeros one obtains magnetic monopoles. The generic defects, however, arise from zeros of second order and are pointlike. Their topological invariant is the Hopf index S^3 -> S^2. These findings are corroborated by an analysis of the Laplacian gauge in the fundamental representation where similar defects occur. Possible implications for the confinement scenario are discussed.
description: 18 pages, 3 figures
Ergodic Isoenergetic Molecular Dynamics for Microcanonical-Ensemble Averages
Creators: name: Hoover, William Graham
name: Hoover, Carol Griswold
Publisher: name: arXiv
Year: 2018
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Considerable research has led to ergodic isothermal dynamics which can replicate Gibbs' canonical distribution for simple ( small ) dynamical problems. Adding one or two thermostat forces to the Hamiltonian motion equations can give an ergodic isothermal dynamics to a harmonic oscillator, to a quartic oscillator, and even to the "Mexican-Hat" ( double-well ) potential problem. We consider here a time-reversible dynamical approach to Gibbs' "microcanonical" ( isoenergetic ) distribution for simple systems. To enable isoenergetic ergodicity we add occasional random rotations to the velocities. This idea conserves energy exactly and can be made to cover the entire energy shell with an ergodic dynamics. We entirely avoid the Poincaré-section holes and island chains typical of Hamiltonian chaos. We illustrate this idea for the simplest possible two-dimensional example, a single particle moving in a periodic square-lattice array of scatterers, the "cell model".
description: Seven pages with three Figures
Additional file 1: of Cellular network modeling and single cell gene expression analysis reveals novel hepatic stellate cell phenotypes controlling liver regeneration dynamics
Creators: name: Cook, Daniel
name: Sirisha Achanta
name: Hoek, Jan
name: Babatunde Ogunnaike
name: Rajanikanth Vadigepalli
Publisher: name: figshare
Year: 2018
Subjects: subject: Biochemistry
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: Developmental Biology
subject: Cancer
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: 60506 Virology
subject: Computational Biology

description: Supplemental figures S1-S13 and Supplemental Tables S1-S4. (DOCX 2680 kb)
与运动行为变化相关的数据
Creators: name: liao, huiling
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 420603
subject: Health promotion
classificationCode: 420799
subject: Sports science and exercise not elsewhere classified
classificationCode: 520304
subject: Health psychology

description: 该数据仅限于大学生群体，对运动行为阶段和学业倦怠这两个主题相关的方面提供研究支持。
MOESM1 of Interrelationship between Changes in the Amyloid Î˛ 42/40 Ratio and Presenilin 1 Conformation
Creators: name: Zoltowska, Katarzyna
name: Maesako, Masato
name: Berezovska, Oksana
Publisher: name: figshare
Year: 2016
Subjects: subject: Biochemistry
subject: Space Science
subject: Cell Biology
subject: Neuroscience
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences

description: Interrelationship between Changes in the Amyloid Î˛ 42/40 Ratio and Presenilin 1 Conformation
Herrschaft vom Pferderücken – Reisekönigtum zur Zeit Heinrichs IV.
Creators: name: Tschiedel, Torben
Publisher: name: Mittelalter Digital
Year: 2021

description: Die Hauptstadt und das Land gehören für moderne Menschen untrennbar zusammen. Eines geht ohne das andere nicht. Bereits in der Grundschule lernen wir die entsprechenden Begriffspaare auswendig. In Hauptstädten wird Politik gemacht, sie sind die Schaltzentrale ihres Landes und der Ort, an dem das Parlament, viele wichtige Ministerien sowie ausländische Konsulate und Botschaften zu finden sind; meistens in einem eigenen Regierungsviertel. Für uns ist die Hauptstadt heute selbstverständlich ein Synonym für das Zentrum der Macht und für diejenigen, die politische Entscheidungen treffen. Demnach „entscheidet Berlin“, man fragt, „was Washington eigentlich denkt“, „welche Zusicherungen Moskau gemacht hat“ und was „Peking dazu sagt“.
description: Mittelalter Digital, Vol 2 No 1 (2021): A.D. 1050
Children Age Group Detection based on Human-Computer Interaction and Time Series Analysis
Creators: name: Ruiz-Garcia, Juan Carlos
name: Hojas, Carlos
name: Tolosana, Ruben
name: Vera-Rodriguez, Ruben
name: Morales, Aythami
name: Fierrez, Julian
name: Ortega-Garcia, Javier
name: Herreros-Rodriguez, Jaime
Publisher: name: arXiv
Year: 2024
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: This article proposes a novel Children-Computer Interaction (CCI) approach for the task of age group detection. This approach focuses on the automatic analysis of the time series generated from the interaction of the children with mobile devices. In particular, we extract a set of 25 time series related to spatial, pressure, and kinematic information of the children interaction while colouring a tree through a pen stylus tablet, a specific test from the large-scale public ChildCIdb database.
 A complete analysis of the proposed approach is carried out using different time series selection techniques to choose the most discriminative ones for the age group detection task: i) a statistical analysis, and ii) an automatic algorithm called Sequential Forward Search (SFS). In addition, different classification algorithms such as Dynamic Time Warping Barycenter Averaging (DBA) and Hidden Markov Models (HMM) are studied. Accuracy results over 85% are achieved, outperforming previous approaches in the literature and in more challenging age group conditions. Finally, the approach presented in this study can benefit many children-related applications, for example, towards an age-appropriate environment with the technology.
description: 10 pages, 6 figures, 6 tables, 32 references
Archival search for recurrent activity at the position the gamma-ray burst GRB 970228 optical counterpart
Creators: name: Gorosabel, Javier
name: Castro-Tirado, Alberto J.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We have examined 8004 plates at the Harvard College Observatory Plate Collection searching for optical transient emission from the gamma-ray burst GRB 970228. This is the first archival search carried out so far for a gamma-ray burst with known transient optical emission. The total exposure time amounts to ~1.1 yr. No convincing optical activity was found above 12.5 mag at the expected position of the GRB 970228 optical counterpart.
description: 2 pages, 1 encapsulated PostScript and 1 jpeg figure included. Uses Astronomy & Astrophysics LaTeX macros. Accepted for publication in A&A
PYY(3-36) analogues: Structure-activity relationships in energy homeostasis
Creators: name: Pritchard, Iain David
Publisher: name: Imperial College London
Year: 2011

description: The developed world is currently in the grip of an obesity epidemic. As a result, there is much ongoing research into the development of an effective anti-obesity agent. Peptide YY (PYY) is a 36 amino acid gastro-intestinal hormone released post-prandially by L-cells in the gastro-intestinal tract in proportion to the calorie content of a meal. The predominant form of the hormone found in circulation is the truncated PYY(3-36). Administration of PYY(3-36) at physiological doses to humans has been shown to reduce food intake. However, due to enzymatic degradation these effects are short lived, reducing the hormone’s utility as an anti-obesity pharmaceutical agent. A series of analogues of PYY(3-36) were designed either with amino acid substitutions in specific parts of the peptide sequence and/or with chemical modifications to the native sequence with the aim of increasing resistance to enzymatic activity whilst retaining or even enhancing the peptide’s bioactivity. The analogues were tested for resistance to degradation by different proteolytic enzymes in comparison to natural PYY(3-36). Their affinity to the Y2 receptor, for which PYY(3-36) is a natural agonist was then investigated. Finally, the effects of peripheral administration of selected analogues on food intake in overnight fasted mice were investigated. These studies suggest that PYY(3-36) analogues may be a useful approach for the treatment of obesity, but further development work is required.
Characterisation and mitigation of long-term degradation effects in programmable logic
Creators: name: Stott, Edward A.
Publisher: name: Imperial College London
Year: 2011

description: Reliability has always been an issue in silicon device engineering, but until now it has been managed by the carefully tuned fabrication process. In the future the underlying physical limitations of silicon-based electronics, plus the practical challenges of manufacturing with such complexity at such a small scale, will lead to a crunch point where transistor-level reliability must be forfeited to continue achieving better productivity. Field-programmable gate arrays (FPGAs) are built on state-of-the-art silicon processes, but it has been recognised for some time that their distinctive characteristics put them in a favourable position over application-specific integrated circuits in the face of the reliability challenge. The literature shows how a regular structure, interchangeable resources and an ability to reconfigure can all be exploited to detect, locate, and overcome degradation and keep an FPGA application running. To fully exploit these characteristics, a better understanding is needed of the behavioural changes that are seen in the resources that make up an FPGA under ageing. Modelling is an attractive approach to this and in this thesis the causes and effects are explored of three important degradation mechanisms. All are shown to have an adverse affect on FPGA operation, but their characteristics show novel opportunities for ageing mitigation. Any modelling exercise is built on assumptions and so an empirical method is developed for investigating ageing on hardware with an accelerated-life test. Here, experiments show that timing degradation due to negative-bias temperature instability is the dominant process in the technology considered. Building on simulated and experimental results, this work also demonstrates a variety of methods for increasing the lifetime of FPGA lookup tables. The pre-emptive measure of wear-levelling is investigated in particular detail, and it is shown by experiment how di fferent reconfiguration algorithms can result in a significant reduction to the rate of degradation.
Hypersexualized Monsters in ›Beowulf‹ Director’s Cut (USA 2007) and the Sharp Objects Constantly Threatening to Castrate Him
Creators: name: Van Beek, Alan Lena
Publisher: name: Mittelalter Digital
Year: 2021

description: This essay explores the 2007 cinematic adaptation of ›Beowulf‹, written by Neil Gaiman and Roger Avary. It will focus on narration, sexuality and virility in in the original poem and hypersexualized bodies in the movie. Gilded genitalia, absent genitalia and the sharp objects constantly threatening to castrate Beowulf are being analysed as a cultural text.
description: Mittelalter Digital, Vol 2 No 1 (2021): A.D. 1050