cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Medium Size Telescopes of the Cherenkov Telescope Array
Creators: name: Pühlhofer, G.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The Cherenkov Telescope Array (CTA) is the planned next-generation instrument for ground-based gamma-ray astronomy, covering a photon energy range of ~20 GeV to above 100 TeV. CTA will consist of the order of 100 telescopes of three sizes, installed at two sites in the Northern and Southern Hemisphere. This contribution deals with the 12 meter Medium Size Telescopes (MST) having a single mirror (modified Davies-Cotton, DC) design. In the baseline design of the CTA arrays, 25 MSTs in the South and 15 MSTs in the North provide the necessary sensitivity for CTA in the core energy range of 100 GeV to 10 TeV. DC-MSTs will be equipped with photomultiplier (PMT)-based cameras. Two options are available for these focal plane instruments, that will be provided by the FlashCam and the NectarCAM sub-consortia. In this contribution, a short introduction to the projects and their status is given.
description: 6 pages, 5 figures, Proceedings of the 6th International Symposium on High-Energy Gamma-Ray Astronomy (Gamma2016)
Stimuli-responsive polymers for application in molecular sensing
Creators: name: Sander, Fiona
Publisher: name: Imperial College London
Year: 2022

description: Stimuli-responsive polymers with the ability to change their properties upon smallest changes in their environment are of strong interest for use in molecular sensors. Among these materials, liquid crystal polymers combine properties of both polymers and mesogens to achieve exceptional responses to a variety of stimuli such as light or temperature. The application of these materials for biosensing has been left largely unexplored despite their high potential in the healthcare and biomedical fields. Within this work we present new sensing methods employing both polymers and mesogens using computational and experimental approaches including Molecular Dynamics and Kinetic Monte Carlo methods with the aim to create novel biosensors. To detect environmental changes we present a novel sensing mechanism based on the hybridisation of DNA and PNA. We show the suitability of hybridisation-based detection of DNA and demonstrate the strong dependence of the gyration radius on the percentage of double-stranded DNA, thus utilising simple polymer physics for the development of new biosensing solutions, exploiting both computational and experimental methods. Following the development of sensing mechanisms, the polymerisation process of functional polymeric materials is analysed. To optimise the time intensive polymer synthesis and enable computational research of close-to-reality systems, a Kinetic Monte Carlo method is proposed within the frame of this thesis which enables simulation of RAFT polymerisations resulting in linear, block or gradient co-polymers. The model predicts polydispersity, composition and structure of the polymer while also offering differentiation between polymer species for detailed analysis of the process. A computational tool for simple, fast and effective parameter studies is presented with the aim of finding optimum polymerisation conditions for desired polymeric products. This leads to a dramatic reduction of time spent on experimental studies prior to successful synthesis in the lab. Based on these outcomes, a Molecular Dynamics (LAMMPS) model is presented for assessment of the influence of polydispersity and persistence length on the formation of liquid crystalline phases within a stimuli-responsive polymer. We show, that environmental stimuli affect the liquid crystalline behaviour in the polymeric materials significantly. As the first study on these aspects of stimuli-responsive polymers, the results presented here suggest a high potential for the application of such materials in optical biosensing of DNA and environmental parameters including pH and temperature. In conclusion, within the frame of this thesis, sensing mechanisms are explored both experimentally and computationally, a Kinetic Monte Carlo procedure to predict properties in functional polymers is proposed and liquid-crystalline polymers for application in biosensing are developed based on Molecular Dynamics simulations.
Random matrix modelling of polarised light scattering in disordered media
Creators: name: Byrnes, Niall Francis
Publisher: name: Imperial College London
Year: 2023

description: The polarisation properties of light are often used as a means of information transfer, as well as in assessing the structural and compositional properties of materials. In many practical situations, however, the propagation of polarised light is impeded by random scattering, which tends to scramble the information content of the underlying fields. Theoretical study of the random scattering of light is an old, complex field of research, in which approximate, numerical methods are often favoured over exact mathematical analysis. Random matrix theory, in which systems are modelled using random scattering matrices, has uncovered universal properties of wide classes of random media, most notably in the field of quantum scattering. Despite also finding success in optics, a random matrix theory of polarised light has yet to be pursued. In this thesis we apply the notion of random matrices to develop statistical techniques for modelling the random scattering of polarised light. We present a full derivation of the symmetries of the vectorial scattering and transfer matrices that describe dielectric scattering media, including the scattering of evanescent wave components. We then consider the circular ensembles as a simple random matrix model and explore its implications for the scattering of polarised light. Moving beyond elementary models, a rigorous, statistical theory of the scattering matrix for discrete random media is presented, and exact mathematical results are derived in certain special cases. A numerical simulation method for studying scattering matrices describing random media of arbitrary thickness is then developed and validated against known physical phenomena. Finally, the techniques developed within this thesis are applied to the problem of the recovery of polarisation information within light that has propagated through a random medium.
On $z$-dominance, shift symmetry and spin locality in higher-spin theory
Creators: name: Didenko, V. E.
name: Korybut, A. V.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The paper aims at the qualitative criterion of higher-spin locality. Perturbative analysis of the Vasiliev equations gives rise to the so-called $z$-dominated non-localities which nevertheless disappear from interaction vertices leaving the final result spin-local in all known cases. This has led one to the $z$ -- dominance conjecture that suggests universality of the observed cancellations. Here we specify conditions which include observation of the higher-spin shift symmetry and prove validity of this recently proposed conjecture. We also define a class of spin-local and shift-symmetric field redefinitions which is argued to be the admissible one with respect to spin-locality.
description: 31 pages
Duality and policy gradient methods for stochastic control problems with controlled diffusions
Creators: name: Davey, Ashley
Publisher: name: Imperial College London
Year: 2023

description: In this thesis we develop numerical algorithms for stochastic control problems where the state processes is an Itˆo process that depends on the control process in both the drift and diffusion functions. We derive sufficient conditions for convergence of a proximal policy gradient method (PPGM) for the stochastic linear quadratic control problem. The optimal control can be uniquely determined by solving a Ricatti equation. We prove that the control induced by the policy gradient method converges to the optimal control. Considering convergence analysis in the general case, we study the underlying backwards stochastic differential equations using Malliavin Calculus, and determine some conditions under which convergence of the control process can be established. To implement the PPGM method, we use concepts in machine learning methods, and extend our algorithms using duality theory. Using deep learning methods, the algorithms developed are scalable to high dimensional problems, with a reasonable runtime. Duality allows us to solve an auxiliary control problem simultaneously to the original primal problem, which allows us to exploit the dual-primal relations between the associated processes, and form tight bounds of the value function. In certain cases solving the dual problem directly bypasses complexity within the primal problem. We further use duality to implement algorithms that can be applied to non-Markovian control problems.
Giant Linear Magneto-resistance in Nonmagnetic PtBi2
Creators: name: Yang, Xiaojun
name: Bai, Hua
name: Wang, Zhen
name: Li, Yupeng
name: Chen, Qian
name: Chen, Jian
name: Li, Yuke
name: Feng, Chunmu
name: Zheng, Yi
name: Xu, Zhu-an
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We synthesized nonmagnetic PtBi$_2$ single crystals and observed a giant linear magneto-resistance (MR) up to 684\% under a magnetic field $μ_0H$ = 15 T at $T$ = 2 K. The linear MR decreases with increasing temperature, but it is still as large as 61\% under $μ_0H$ of 15 T at room temperature. Such a giant linear MR is unlikely to be described by the quantum model as the quantum condition is not satisfied. Instead, we found that the slope of MR scales with the Hall mobility, and it can be well explained by a classical disorder model.
description: Accepted for publication in APL
Some Features of Scattering Problem in a $κ$-Deformed Minkowski Spacetime
Creators: name: Khodadi, Mohsen
name: Nozari, Kourosh
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The doubly special relativity (DSR) theories are suggested in order to incorporate an observer-independent length scale in special theory of relativity. The Magueijo-Smolin proposal of DSR is realizable through a particular form of the noncommutative (NC) spacetime (known as $κ$-Minkowski spacetime) in which the Lorentz symmetry is preserved. In this framework, the NC parameter $κ$ provides the origin of natural cutoff energy scale. Using a nonlinear deformed relativistic dispersion relation along with the Lorentz transformations, we investigate some phenomenological facets of two-body collision problem (without creation of new particles) in a $κ$-Minkowski spacetime. By treating an elastic scattering problem, we study effects of the Planck scale energy cutoff on some relativistic kinematical properties of this scattering problem. The results are challenging in the sense that as soon as one turns on the $κ$-spacetime extension, the nature of the two-body collision alters from elastic to inelastic one. It is shown also that a significant kinematical variable involving in heavy ion collisions, the rapidity, is not essentially an additive quantity under a sequence of the nonlinear representation of the Lorentz transformations.
description: 16 pages, 2 figures, Accepted for Publication in Annalen der Physik
Modelling electrochemical and thermal behaviors of silicon-based electrodes for lithium-ion batteries
Creators: name: Jiang, Yang
Publisher: name: Imperial College London
Year: 2023

description: Silicon (Si) has become an attractive alternative to graphite (Gr) as an anode material for the next generation lithium-ion batteries (LIBs) due to its high theoretical capacity, natural abundance, and reasonable electrode potential. However, Si-based electrodes exhibit distinct electrochemical and thermal behaviors compared to traditionally used carbonaceous electrode, and there have been rare models tailored to the behaviors of Si-based electrodes. Therefore, this thesis aims to develop physics-based models able to describe and predict the electrochemical and thermal behaviors of Si-based electrodes, which can serve as important tools for understanding and designing LIBs with Si-based anodes. A mechanistic model of silicon anodes in LIBs is first developed to describe the unique voltage hysteresis phenomenon of silicon electrodes. The model correlates the voltage hysteresis of Si to its underlying phase transformation, crystallization and amorphization processes. The effects of crystallization rate and surface energy barriers are studied, unveiling the role of surface energy and particle size in determining the performance behaviors of Si. Subsequently, a multi-material model is developed for simulating Si/Gr composite electrodes, considering different behaviors of Gr and Si. Results show that silicon introduces voltage hysteresis to Si/Gr electrodes. The (de)lithiation sequence and competing processes between Si and Gr are comprehensively studied. A dimensionless competing factor is derived to quantify the active operating regions for each material, and demonstrates to be a useful indicator to design cycling protocols for mitigating the degradation of composite electrodes. The multi-material model is further coupled with a thermal submodel. By studying the respective heat contributions of each active material, the model reveals the origin of thermal peaks of Si/Gr composite electrodes, which are highly related to the phase transition processes of Gr. These thermal peaks can be potentially used to detect the ageing of Si-based batteries in service.
Trapping Centers at the Superfluid-Mott-insulator Criticality: Transition between Charge-quantized States
Creators: name: Huang, Yuan
name: Chen, Kun
name: Deng, Youjin
name: Svistunov, Boris
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Under the conditions of superfluid-Mott-insulator criticality in two dimensions, the trapping centers--i.e., local potential wells and bumps--are generically characterized by an integer charge corresponding to the number of trapped particles (if positive) or holes (if negative). Varying the strength of the center leads to a transition between two competing ground states with charges differing by $\pm 1$. The hallmark of the transition scenario is a splitting of the number density distortion, $δn(r)$, into a half-integer core and a large halo carrying the complementary charge of $\pm 1/2$. The sign of the halo changes across the transition and the radius of the halo, $r_0$, diverges on the approach to the critical strength of the center, $V = V_c$, by the law $r_0 \propto |V-V_c|^{-\tildeν}$, with $\tildeν \approx 2.33(5)$.
description: 5 pages, 5 figures
The role of metagenomics as novel sequencing-based tools in analysing the virome of patients with severe community-acquired pneumonia
Creators: name: Ainley, Adam Denis Jeremy
Publisher: name: Imperial College London
Year: 2022

description: Abstract The role of metagenomics as novel sequencing-based tools in obtaining a virological diagnosis and analysing the underlying virome of patients with severe community-acquired pneumonia. Aims: To develop a metagenomic sequencing (MGS) workflow with the ability to detect viral pathogens in bronchoalveolar lavage samples from patients with severe community-acquired pneumonia (SCAP) and improve understanding of the respiratory virome. Methods: In parallel to developing a new MGS workflow, a protocol for a multi-centre study was devised whilst establishing a network of clinical centres to undertake clinical research. Ethical approval was sought and once approved led to the undertaking of The SCAP study, a multicentre clinical trial established to recruit patients with SCAP. In addition to recruiting patients from one of the 5 commissioned ECMO centres who formed part of the established network, patients were also recruited from intensive care units and a dedicated research bronchoscopy service used to sample healthy volunteers. During the recruitment stage, an evaluation and refinement of a metagenomic protocol was undertaken using a novel reference reagent. The sequencing data generated was used to establish and evaluate a bioinformatic pipeline to compliment the laboratory processes developed and a pilot study undertaken to assess the workflows detection ability. Results: 101 patients were successfully recruited over 3 seasons and an invaluable biobank of upper and lower respiratory tract samples was curated alongside a wealth of clinical data and additional complimentary clinical samples. When applied to the BAL samples collected, MGS was able to detect a virus in 30% of subjects and showed comparable specificity and concordance to conventional diagnostics and an extended suite of molecular assays although a limit of detection was noted. Conclusion: The SCAP study was one of the first studies to explore the use MGS in patients with SCAP from a virological perspective and generated to date, one of the largest collections of BAL samples for MGS analysis and undertook one of few existing comparisons to a healthy cohort.
Dynamical optical conductivity for gapped $α-\mathcal{T}_3$ materials with a curved "flat" band
Creators: name: Iurov, Andrii
name: Zhemchuzhna, Liubov
name: Gumbs, Godfrey
name: Huang, Danhong
Publisher: name: arXiv
Year: 2022
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We have calculated the dynamical optical conductivity for $α-\mathcal{T}_3$ materials in the presence of a finite bandgap in their energy bandstructure. This is a special type of energy dispersions because for all $α-\mathcal{T}_3$ materials with a bandgap, except graphene and a dice lattice limits, the flat band receives a non-zero dispersion and assumes a curved shape. The infinite ${\bf k}$-degeneracy of the flat energy band is also lifted. Such a low-energy bandstructure could be obtained if an $α-\mathcal{T}_3$ material is irradiated off-resonant with circularly polarized light. We have calculated the optical conductivity for the zero and finite temperatures, as well as for the cases of a finite and nearly-zero doping. We have demonstrated that analytical expressions could be in principle obtained for all types of gapped $α-\mathcal{T}_3$ materials and provided the closed-form analytical expressions for a gapped dice lattice. Our numerical results reveal some well-known signatures of the optical conductivity in $α-\mathcal{T}_3$ and silicene with two non-equivalent bandgaps, as well as demonstrate some very specific features which have not been previously found in any existing Dirac materials.
description: 17 pages, 4 figures
Modes and exceptional points in waveguides with impedance boundary conditions
Creators: name: Midya, Bikashkali
name: Konotop, Vladimir V.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Optics (physics.optics)
subject: Mathematical Physics (math-ph)
subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: A planar waveguide with impedance boundary, composed of non-perfect metallic plates, and with passive or active dielectric filling is considered. We show the possibility of selective mode guiding and amplification when homogeneous pump is added to the dielectric, and analyze differences in TE and TM mode propagation. Such a non-conservative system is also shown to feature exceptional points, for specific and experimentally tunable parameters, which are described for a particular case of transparent dielectric.
description: Optics Letters (2016)
Modular microfluidic platform for solubility measurement, nucleation statistics and polymorph screening of active pharmaceutical ingredients: Irbesartan, Rimonabant, Aripiprazole and Sulfathiazole
Creators: name: Lambert, Mathilde
name: Grossier, Romain
name: Lagaize, Mehdi
name: Bactivelane, Thirou
name: Heresanu, Vasile
name: Robert, Benoît
name: Candoni, Nadine
name: Veesler, Stéphane
Publisher: name: arXiv
Year: 2022
Subjects: subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Drug efficacy strongly relies on the solid state of the active pharmaceutical ingredient. Classical solid-state screening methods involve different solvent compositions and supersaturations. Moreover, the many repeat experiments needed to address the stochasticity of nucleation make this approach costly. This paper presents a newly developed modular microfluidic platform that provides a universal and flexible plug-and-play tool for crystallisation studies without use of surfactants. By dissolving a powder, our setup generates saturated solutions that can be used for solubility measurements or distributed in microdroplets. Here, we describe solubility measurements performed on different forms, stable and metastable, of pharmaceutical molecules (Irbesartan, Rimonabant and Aripiprazole) in organic and aqueous solvents. In addition, we provide nucleation statistics obtained for Sulfathiazole in water and in acetonitrile. Reporting polymorph screening on Sulfathiazole and statistics for nucleated forms, we find that the cooling rate influences both nucleation and polymorphism results, reflecting the competition between thermodynamics and kinetics. Three unknown forms were discovered, with XRD patterns and Raman spectra that do not match any referenced form. We also demonstrate the limitations of microfluidics for crystallisation by cooling: reducing the crystalliser volume considerably increases nucleation induction time.
Geomagnetically trapped, albedo and solar energetic particles: trajectory analysis and flux reconstruction with PAMELA
Creators: name: Bruno, A.
name: Adriani, O.
name: Barbarino, G. C.
name: Bazilevskaya, G. A.
name: Bellotti, R.
name: Boezio, M.
name: Bogomolov, E. A.
name: Bongi, M.
name: Bonvicini, V.
name: Bottai, S.
name: Cafagna, F.
name: Campana, D.
name: Carlson, P.
name: Casolino, M.
name: Castellini, G.
name: Christian, E. C.
name: De Donato, C.
name: de Nolfo, G. A.
name: De Santis, C.
name: De Simone, N.
name: Di Felice, V.
name: Galper, A. M.
name: Karelin, A. V.
name: Koldashov, S. V.
name: Koldobskiy, S.
name: Krutkov, S. Y.
name: Kvashnin, A. N.
name: Leonov, A.
name: Malakhov, V.
name: Marcelli, L.
name: Martucci, M.
name: Mayorov, A. G.
name: Menn, W.
name: Mergé, M.
name: Mikhailov, V. V.
name: Mocchiutti, E.
name: Monaco, A.
name: Mori, N.
name: Munini, R.
name: Osteria, G.
name: Palma, F.
name: Panico, B.
name: Papini, P.
name: Pearce, M.
name: Picozza, P.
name: Ricci, M.
name: Ricciarini, S. B.
name: Ryan, J. M.
name: Sarkar, R.
name: Scotti, V.
name: Simon, M.
name: Sparvoli, R.
name: Spillantini, P.
name: Stochaj, S.
name: Stozhkov, Y. I.
name: Vacchi, A.
name: Vannuccini, E.
name: Vasilyev, G. I.
name: Voronov, S. A.
name: Yurkin, Y. T.
name: Zampa, G.
name: Zampa, N.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: The PAMELA satellite experiment is providing comprehensive observations of the interplanetary and magnetospheric radiation in the near-Earth environment. Thanks to its identification capabilities and the semi-polar orbit, PAMELA is able to precisely measure the energetic spectra and the angular distributions of the different cosmic-ray populations over a wide latitude region, including geomagnetically trapped and albedo particles. Its observations comprise the solar energetic particle events between solar cycles 23 and 24, and the geomagnetic cutoff variations during magnetospheric storms. PAMELA's measurements are supported by an accurate analysis of particle trajectories in the Earth's magnetosphere based on a realistic geomagnetic field modeling, which allows the classification of particle populations of different origin and the investigation of the asymptotic directions of arrival.
description: Accepted for publication in Advances in Space Research, 2016. 21 pages, 7 figures
Chiral approach to partially-massless fields
Creators: name: Basile, Thomas
name: Dhasmana, Shailesh
name: Skvortsov, Evgeny
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We propose a new (chiral) description of partially-massless fields in $4d$, including the partially-massless graviton, that is similar to the pure connection formulation for gravity and massless higher spin fields, the latter having a clear twistor origin. The new approach allows us to construct complete examples of higher spin gravities with (partially-)massless fields that feature Yang--Mills and current interactions.
description: 22 pages, 3 figures
The Effect of Internal Damping on Locomotion in Frictional Environments
Creators: name: Van Stratum, Brian
name: Clark, Jonathan E.
name: Shoele, Kourosh
Publisher: name: arXiv
Year: 2022
Subjects: subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: The gaits of undulating animals arise from a complex interaction of their central nervous system, muscle, connective tissue, bone, and environment. As a simplifying assumption, many previous studies have often assumed that sufficient internal force is available to produce observed kinematics, thus not focusing on quantifying the interconnection between muscle effort, body shape, and external reaction forces. This interplay, however, is critical to locomotion performance in crawling animals, especially when accompanied by body viscoelasticity. Moreover, in bio-inspired robotic applications, the body's internal damping is indeed a parameter that the designer can tune. Still, the effect of internal damping is not well understood. This study explores how internal damping affects the locomotion performance of a crawler with a continuous, visco-elastic, nonlinear beam model. Crawler muscle actuation is modeled as a traveling wave of bending moment propagating posteriorly along the body. Consistent with the friction properties of the scales of snakes and limbless lizards, environmental forces are modeled using anisotropic Coulomb friction. It is found that by varying the crawler body's internal damping, the crawler's performance can be altered, and distinct gaits could be achieved, including changing the net locomotion direction from forward to back. We will discuss this forward and backward control and identify the optimal internal damping for peak crawling speed.
The Oulipo and Modernism: Literature, Craft and Mathematical Form
Creators: name: Cartwright, Daniel
Publisher: name: University of Westminster
Year: 2019

description: The Oulipo is known primarily for the use of formal constraints in writing. The constraint is an arbitrary application of rigorously defined formal demands (often drawn from mathematics) in the process of literary or poetic composition. The group was founded in 1960, and their remit was limited to the formulation of constraints rather than literary texts. There is thus no literary theory proposed by the Oulipo, and little in the way of critical interpretation of their methods in terms of its wider significance to the condition of art in the period of their emergence. Their approach is often counterposed to the Surrealists: where the Surrealist response to the conditions of rationalised modernity attempted to explore the unconscious, the non-rational and chance, the Oulipo’s use of constraints is consciously determined and resists the passivity of chance. The counter-model to the Surrealists for the Oulipo is the mathematical collectiveNicolas Bourbaki. Bourbaki’s rigorously abstract axiomaticmathematics provides the formal prototype of the most abstracted rationality for the Oulipo to use as compositional structures. The Oulipo also bear an ambivalent relation to structuralism, but where structuralism tends towards a descriptive identification of ‘deep structures’ of signification, the Oulipo instead deploy structures as historically-specific compositional material. This thesis proposes to read the practice of the Oulipo as a production of the ‘new’ through a form of construction as ‘craft’ that is itself receptive to critical interpretation. It contends that the Oulipo can be seen to offer a distinctive trajectory among the various responses to what Adorno identifies as a crisis of art’s autonomy in the latter half of the twentieth century; in other words, that they pursue an alternative modernism. I argue that the Oulipo’s use of arbitrary rigidified logical structures in literary composition is categorially alien to the latter’s concept, and thus that it forms a kind of resistant material which must be worked with. This model of skilled engagement recalls, in self-consciously paradoxical ways, the outmoded concept of craft which provides an alternative to, on the one hand, the post-romantic idea of artistic freedom, and on the other, full subsumption by technological procedure, maintaining a refracted instrumentality in the logic of method that yet resists pre-determination.
Kinetic analysis of negative power deposition in low pressure plasmas
Creators: name: Trieschmann, Jan
name: Mussenbrock, Thomas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: The negative power absorption in low pressure plasmas is investigated by means of an analyical model which couples Boltzmann's equation and the quasi-stationary Maxwell's equation. Exploiting standard Hilbert space methods an explicit solution for both, the electric field and the distribution function of the electrons for a bounded discharge configuration subject to an unsymmetrical excitation has been found for the first time. The model is applied to a low pressure inductively coupled plasma discharge. In this context particularly the anomalous skin effect and the effect of phase mixing is discussed. The analytical solution is compared with results from electromagnetic full wave particle in cell simulations. Excellent agreement between the analytical and the numerical results is found.
On the backreaction issue for the black hole in de Sitter space-time
Creators: name: Akhmedov, E. T.
name: Bazarov, K. V.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We consider quantum real massive scalar field in the de Sitter-Schwarzschild space-time backround. To have an analytic head way we study in detail the two-dimensional case, assuming that the situation in four dimensions will not be much different conceptually. It is assumed, that quantum field is in a thermal state i.e. described by the planckian distribution for the exact modes in the geometry under consideration. We calculate approximately the expectation value of stress-energy tensor near the cosmological and black hole horizons. It is shown that for a generic temperature backreaction from quantum fields on the geometry cannot be neglected. Thus, de Sitter-Schwarzschild space-time geometry inevitably is strongly modified by the quantum fluctuations of the matter fields.
description: 10 pages, references, comments and calculation details added
Asteroseismology of hybrid $δ$ Scuti--$γ$ Doradus pulsating stars
Creators: name: Arias, J. P. Sánchez
name: Córsico, A. H.
name: Althaus, L. G.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Hybrid $δ$ Scuti-$γ$ Doradus pulsating stars show acoustic ($p$) oscillation modes typical of $δ$ Scuti variable stars, and gravity ($g$) pulsation modes characteristic of $γ$ Doradus variable stars simultaneously excited. Observations from space missions like MOST, CoRoT, and \emph{Kepler} have revealed a large number of hybrid $δ$ Scuti-$γ$ Doradus pulsators, thus paving the way for a exciting new channel for asteroseismic studies. We perform a detailed asteroseismological modeling of five hybrid $δ$ Scuti-$γ$ Doradus stars. We employ a grid-based modeling approach to sound the internal structure of the target stars by employing a huge grid of stellar models from the zero-age main sequence to the terminal-age main sequence, varying parameters like stellar mass, effective temperature, metallicity and core overshooting. We compute their adiabatic radial ($\ell= 0$) and non-radial ($\ell= 1, 2, 3$) $p$ and $g$ mode periods. We employ two model-fitting procedures to searching for the models that best reproduce the observed pulsation spectra of each target star, that is, the asteroseismological models. We derive the fundamental parameters and the evolutionary status of five hybrid $δ$ Scuti-$γ$ Doradus variable stars recently observed with the CoRoT and \emph{Kepler} space missions: CoRoT 105733033, CoRoT 100866999, KIC 11145123, KIC 9244992, and HD 49434. The asteroseismological model for each star results from different criteria of model selection, in which we take full advantage of the richness of periods that characterizes the pulsation spectra of this kind of stars.
description: 18 pages, 23 figures, 11 tables. To be published in Astronomy and Astrophysics
Gauged Double Field Theory, Current Algebras and Heterotic Sigma Models
Creators: name: Hatsuda, Machiko
name: Mori, Haruka
name: Sasaki, Shin
name: Yata, Masaya
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the $O(D,D+n)$ generalized metric and the gauge symmetries in the gauged double field theory (DFT) in view of current algebras and sigma models. We show that the $O(D,D+n)$ generalized metric in the gauged DFT is consistent with the heterotic sigma models at the leading order in the $α'$-corrections. We then study the non-Abelian gauge symmetries and current algebras of heterotic string theories. We show that the algebras exhibit the correct diffeomorphism, the $B$-field gauge transformations of the background fields together with the non-Abelian gauge transformations possibly with the appropriate local Lorentz transformations.
description: 20 pages, minor corrections, version appeared in JHEP
The expression and signalling patterns of CD180 toll like receptor in Chronic Lymphocytic Leukaemia (CLL)
Creators: name: Sayed, Uzma
Publisher: name: University of Westminster
Year: 2019

description: Chronic lymphocytic leukaemia (CLL) is characterised by a progressive accumulation of mature CD5+CD20+CD23+ lymphocytes. Despite the remarkable progress in our understanding of the immunobiology of CLL, the aetiology of the disease remains unknown. The consensus is that CLL cells are driven by (auto)antigen(s) through the B cell receptor (BCR) and are regulated by a variety of signals received from the microenvironment, including toll-like receptors (TLR).Our group has previously shown that engagement of the CD180 orphan TLR expressed by approximately 60% of CLL cells, can re-wire the sIgM-mediated signalling from a pro-survival pathway, involving phosphatidylinositol-4,5-bisphosphate3-kinase (PI3K) and protein kinase B (AKT) to the potentially pro-apoptotic pathway through mitogen-activated protein kinase (p38MAPK). However, little is known about the function of the other BCR - sIgD in CLL and its possible interaction with CD180. Here we studied intracellular signalling and apoptosis of CLL cells following sole or sequential ligation of CD180 and sIgD. Our data indicated that following sequential ligation of CD180 and sIgD, CLL samples demonstrated enhanced p38MAPK phosphorylation leading to increased apoptosis of CLL cells indicating synergistic relationship between CD180 and sIgD. To better understand the prognostic importance of CD180 expression we sought to determine whether CD180 and other prognostic markers such as CD38 and ZAP70 displayed any correlation with the known cytogenetic aberrations:TP53 and DLEU1. Our results suggested that CLL cells with DLEU1 deletion are characterised by the negative expression of both, CD180 and CD38, and this might have a significance for CLL prognosis. To explain this correlation, we hypothesised that interaction of CLL cells with their microenvironment through TLRs leads to the expansion of leukaemic clones, in vivo, in lymph nodes. Our results indicated that CD180 is heterogeneously expressed in the paraffin tissue sections of the lymph nodes of CLL patients and its expression positively correlates with the expression of Ki-67. Our data demonstrated, that although CD180 expression and signaling might have negative prognostic importance in CLL due to the enhanced proliferation of leukaemic cells, its interaction with sIgD would re-direct leukaemic cells towards apoptosis thus opening new opportunities for the disease immunotherapy.
Content Based Image Retrieval (CBIR) in Remote Clinical Diagnosis and Healthcare
Creators: name: Herrmann, Albany E.
name: Estrela, Vania Vieira
Publisher: name: arXiv
Year: 2016
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Content-Based Image Retrieval (CBIR) locates, retrieves and displays images alike to one given as a query, using a set of features. It demands accessible data in medical archives and from medical equipment, to infer meaning after some processing. A problem similar in some sense to the target image can aid clinicians. CBIR complements text-based retrieval and improves evidence-based diagnosis, administration, teaching, and research in healthcare. It facilitates visual/automatic diagnosis and decision-making in real-time remote consultation/screening, store-and-forward tests, home care assistance and overall patient surveillance. Metrics help comparing visual data and improve diagnostic. Specially designed architectures can benefit from the application scenario. CBIR use calls for file storage standardization, querying procedures, efficient image transmission, realistic databases, global availability, access simplicity, and Internet-based structures. This chapter recommends important and complex aspects required to handle visual content in healthcare.
description: 28 pages, 6 figures, Book Chapter from "Encyclopedia of E-Health and Telemedicine"
title: 40 Jahre feministische studien – woher sie kommen, wohin sie gehen
Creators: name: Oloff, Aline
name: Othmer, Regine
name: Beaufaÿs, Sandra
Publisher: name: DuEPublico
Year: 2023

description: Die feministischen studien, Zeitschrift für interdisziplinäre Frauen- und Geschlechterforschung, sind eine Institution in der deutschsprachigen Fach-Community. Entstanden in den frühen 1980er-Jahren, können anhand ihrer Entwicklung die Veränderungen im Diskurs über die letzten Jahrzehnte nachvollzogen werden. Sandra Beaufaÿs sprach mit zwei der aktuellen Herausgeberinnen, Regine Othmer (Jg. 1946) und Aline Oloff (Jg. 1975).
description: blog interdisziplinäre geschlechterforschung
title: Nachtrag: zum Tod von Adrian de Silva (1966-2023)
Creators: name: Bauer, Robin
name: Schirmer, Utan
name: Weiß, Tomka
Publisher: name: Melusina Press
Year: 2023
Subjects: Transsexualität
Transgender
queer
Männlichkeiten
visuelle Politiken
Heteronormativität
Kunstwissenschaft
Kulturwissenschaft
Fotografie
Geschlechterforschung
gender
Magnus Hirschfeld
Del LaGrace Volcano
Loren Cameron.

description: Von Fröschen, Einhörnern und Schmetterlingen. Trans*_queere Wirklichkeiten und visuelle Politiken. Schriften von Josch Hoenes (1972-2019) -
description: Der Kunst- und Kulturwissenschaftler und trans* Aktivist Josch Hoenes (1972-2019) hat mit seinen Arbeiten an den Schnittstellen von Wissenschaft, Kunst, (Sub-)Kultur und Politik das noch im Entstehen begriffene Feld der Transgender Studies im deutschsprachigen Raum in den 2000er und 2010er Jahren geprägt wie wohl niemand sonst. Sein besonderes Interesse galt der Frage nach dem Potenzial kulturell-künstlerischer Arbeiten, in hegemoniale Repräsentationen und Wissensweisen von Geschlecht zu intervenieren und vielfältige (trans*-)geschlechtliche Seinsweisen denk- und lebbarer werden zu lassen. Mit der Wiederveröffentlichung ausgewählter Texte von Josch Hoenes im vorliegenden Sammelband soll sein unvollendetes Werk gebündelt zugänglich gemacht werden, um die damit verbundenen mannigfaltigen Impulse lebendig zu halten: Impulse für die wissenschaftlichen Felder vor allem der Transgender Studies, Gender und Queer Studies, Kunst-, Kultur- und Medienwissenschaften, aber auch für einen breit angelegten Aktivismus, der politische Interventionen und das Schaffen von Räumen und Netzwerken ebenso umfasst wie künstlerisches Wirken als Kritik und Utopie. Gerahmt werden die Texte durch den im Dialog mit den Texten entstandenen Bilderzyklus von Tomka Weiß.
MPEC 2024-B157 : 2024 BJ3
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2024 BJ3

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IJSSEv10i1Paper-12.pdf
Creators: name: Serag, Sarah
Publisher: name: figshare
Year: 2021
Subjects: classificationCode: 389999
subject: Other economics not elsewhere classified

description: In this study, the researcher examines the impact of parental education and employment status on children's household wealth in Egypt across three generations (1960s, 1970s, and 1980s). Using the ordinal logistic regression model, the results indicate a significant effect of mothers’ and fathers’ level of education and employment status on their children’s level of wealth. Mothers who work seem to have a negative impact on their children’s level of wealth compared to mothers who don’t work, which may indicate that mothers in low classes may need to work more than mothers from higher classes in Egypt. In addition, fathers who work as wage workers decrease the odds of their children to be in the highest level of wealth compared to fathers who work as employers or self-employed. The results also indicate a positive impact of parental level of education on their children level of wealth; however, the effect of mothers’ level of education was greater than fathers in two generations. These results may also indicate that despite the effect of children’s education, income, and qualifications that should affect their level of wealth, parental education and employment status are important factors that may affect their children’s level of wealth.
CMB-S4 and the Hemispherical Variance Anomaly
Creators: name: O'Dwyer, Marcio
name: Copi, Craig J.
name: Knox, Lloyd
name: Starkman, Glenn D.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Cosmic Microwave Background (CMB) full-sky temperature data show a hemispherical asymmetry in power nearly aligned with the Ecliptic. In real space, this anomaly can be quantified by the temperature variance in the northern and southern Ecliptic hemispheres. In this context, the northern hemisphere displays an anomalously low variance while the southern hemisphere appears unremarkable (consistent with expectations from the best-fitting theory, $Λ$CDM). While this is a well established result in temperature, the low signal-to-noise ratio in current polarization data prevents a similar comparison. This will change with a proposed ground-based CMB experiment, CMB-S4. With that in mind, we generate realizations of polarization maps constrained by the temperature data and predict the distribution of the hemispherical variance in polarization considering two different sky coverage scenarios possible in CMB-S4: full Ecliptic north coverage and just the portion of the North that can be observed from a ground based telescope at the high Chilean Atacama plateau. We find that even in the set of realizations constrained by the temperature data, the low northern hemisphere variance observed in temperature is not expected in polarization. Therefore, an anomalously low variance detection in polarization would provide strong evidence against the hypothesis that the temperature anomaly is simply a statistical fluke. We show, within $Λ$CDM, how variance measurements in both sky coverage scenarios are related. We find that the variance makes for a good statistic in cases where the sky coverage is limited, however a full northern coverage is still preferable.
description: 7 pages, 3 figures
On Quantum Information Before the Page Time
Creators: name: Kudler-Flam, Jonah
name: Kusuki, Yuya
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: While recent progress in the black hole information problem has shown that the entropy of Hawking radiation follows a unitary Page curve, the quantum state of Hawking radiation prior the Page time is still treated as purely thermal, containing no information about the microstructure of the black hole. We demonstrate that there is significant quantum information regarding the quantum state of the black hole in the Hawking radiation prior to the Page time. By computing of the quantum fidelity in a 2D boundary conformal field theory (BCFT) model of black hole evaporation, we demonstrate that an observer outside of an evaporating black hole may distinguish different black holes via measurements of the Hawking radiation at \textit{any} time during the evaporation process, albeit with an exponentially large number of measurements. Furthermore, our results are universal, applicable to general BCFTs including those with large central charge and rational BCFTs. The techniques we develop for computing the fidelity are more generally applicable to excited states in CFT. As such, we are able to characterize more general aspects of thermalization in 2D conformal field theory.
description: 17 pages
Saturation and geometrical scaling
Creators: name: Praszalowicz, Michal
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss emergence of geometrical scaling as a consequence of the nonlinear evolution equations of QCD, which generate a new dynamical scale, known as the saturation momentum: Qs. In the kinematical region where no other energy scales exist, particle spectra exhibit geometrical scaling (GS), i.e. they depend on the ratio pT=Qs, and the energy dependence enters solely through the energy dependence of the saturation momentum. We confront the hypothesis of GS in different systems with experimental data.
description: 6 pages, 4 figures, based on talk presented at XLVI International Symposium on Multiparticle Dynamics, 29 August 2016 to 02 September 2016, Seogwipo, Jeju Island, South Korea