cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Exceptional covers of surfaces
Creators: name: Achter, Jeff
Publisher: name: arXiv
Year: 2007
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 11G25

description: Consider a finite morphism f:X -> Y of smooth projective varieties over a finite field k. Suppose X is the vanishing locus in projective N-space of at most r forms of degree at most d. We show there is a constant C, depending only on N, r, d and deg(f) such that if #k > C, then f(k):X(k) -> Y(k) is injective if and only if it's surjective.
title: Palynostratigraphy of dinosaur bone-bearing deposits from the Upper Cretaceous of Western Bulgaria
Creators: name: (:Unav)
Publisher: name: Komitet Nauk Geologicznych PAN
Year: 2019
Subjects: subject: palynology
subject: Normapolles
subject: Titanosauria
subject: Santonian
subject: Campanian
subject: Palaeoecology

description: Acta Geologica Polonica publishes original papers on all aspects of geology. These papers must not have been published or submitted for publication elsewhere, in entirety or in part. The articles should be of moderate length (up to 80 manuscript pages). Longer manuscripts may be accepted but authors should consult the editor before submitting these. Starting with 2012 you have free access to full texts of all published articles. Acta Geologica Polonica is now (beginning with volume 54(1) for 2004) in the following Thomson ISI products: Science Citation Index-Expanded (SCIE), including the Web of Science, Current Contents/Physical, Chemical & Earth Sciences, ISI Alerting Services. IF for 2019 = 0.797; 5-Year Impact Factor = 1.218  Score of the Ministry of Science and Higher Education = 70
description: Palynological investigation of the Vrabchov dol locality (Western Bulgaria) which recently yielded fragmentary dinosaur bones attributed to the clade Titanosauria, reveals well-preserved sporomorph assemblages dominated by angiosperm pollen from the Normapolles group, spores and rare gymnosperms. The age assessment of the studied sequence is based on the diagnostic Normapolles species, such as Oculopollis orbicularis Góczán, 1964, Oculopollis zaklinskaiae Góczán, 1964, Krutzschipollis spatiosus Góczán in Góczán et al., 1967 and Krutzschipollis crassus (Góczán, 1964) Góczán in Góczán et al., 1967. The concurrent presence of these pollen species suggests a late Santonian–early Campanian age for the succession. The sporomorph association is encountered in a palynofacies dominated by continental elements, including translucent phytoclasts (tissues, wood remains and plant cuticles). The sedimentary succession shows no evidence of marine elements and a very low proportion of AOM that attests to deposition within a lagoonal to foreshore marine environment, with high continental input and short transportation. The vegetation in the studied area was primarily composed of a range of Normapolles-producing angiosperms and secondarily of pteridophyte spore-producing plants. Gymnosperms were rare. Such a vegetation pattern reflects a warm, seasonally dry climate during the late Santonian–earliest Campanian in the studied area. The dinosaurs inhabited a wet lowland area, probably rich in herbaceous plants.
Design, analysis and control of DC/DC converter based DC wind farms
Creators: name: Sang, Yu
Publisher: name: Imperial College London
Year: 2019

description: This thesis discusses the design, operation and control of DC wind farms that use high power DC/DC converters, DC cables and DC collection networks. DC wind farms are proposed as alternatives to traditional AC wind farms due to the potential to reduce the system size, improve the speed of dynamic response and improve the system efficiency. DC wind farms involve different types of high-power DC/DC converters in different stages of power conversion. Isolated DC/DC converters are chosen as the wind turbine converters in which the intermediate transformer design is of great importance. A general and comprehensive medium frequency transformer modelling and design methodology is presented in this thesis, which considers the efficiency, leakage inductance and thermal management. The proposed methodology is applied to transformers for single phase and three phase DC/DC converters. Isolated Single Active Bridge DC/DC converters are appealing topologies for medium voltage applications. The operation of these DC/DC converters is complex and important for the converter control design. The comprehensive operational principles of three-phase single active bridge converters under changing duty cycle are investigated. Eight operating modes are identified with detailed derivation of power flow and current dynamics. The converter performances are evaluated and compared theoretically and experimentally. Then, the control of wind turbine converters in DC wind farms is designed considering both DC-link and network dynamics. To deal with the oscillations caused by smoothing reactors, a power system stabilizer based control design is developed and implemented. Furthermore, a multi-variable feedback control design using pole-placement technique is proposed. This method is able to achieve the minimum oscillatory time without compromising the dynamic performance of the DC-link voltage. Finally, taking into account the low capacitance issue in wind farms, the voltage stability of DC wind farms is investigated and different stabilizing methods are designed and analyzed. The impedance models of aggregated wind turbine converters, DC cables and the station DC/DC converter with control action are derived, in order to study the interactions between the station converter and the DC wind farm. A new equivalent capacitor control strategy to enhance the system capacitance is proposed and analyzed through various case studies.
Do static atoms outside a Schwarzschild black hole spontaneously excite?
Creators: name: Yu, Hongwei
name: Zhou, Wenting
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The spontaneous excitation of a two-level atom held static outside a four dimensional Schwarzschild black hole and in interaction with a massless scalar field in the Boulware, Unruh and Hartle-Hawking vacuum is investigated and the contributions of the vacuum fluctuations and radiation reaction to the rate of change of the mean atomic energy are calculated separately. We find that for the Boulware vacuum, the spontaneous excitation does not occur and the ground state atoms are stable, while the spontaneous emission rate for excited atoms in the Boulware vacuum, which is well-behaved at the event horizon, is not the same as that in the usual Minkowski vacuum. However, both for the Unruh vacuum and the Hartle-Hawking vacuum, our results show that the atom would spontaneously excite, as if there were an outgoing thermal flux of radiation or as if it were in a thermal bath of radiation at a proper temperature which reduces to the Hawking temperature in the spatial asymptotic region, depending on whether the scalar field is in the Unruh or Hartle-Hawking vacuum.
description: 15 pages, no figures, to be published in PRD
Claire Bishop, Disordered Attention. How We Look at Art and Performance Today
Creators: name: Kernbauer, Eva
Publisher: name: 21: Inquiries into Art, History, and the Visual
Year: 2025

description: 21: Inquiries into Art, History, and the Visual, Vol. 6 No. 1 (2025): 21: Inquiries into Art, History, and the Visual. Beiträge zur Kunstgeschichte und visuellen Kultur
Chemosensitivity associated chromatin conformation changes and genomic cisplatin-DNA adduct distribution
Creators: name: Gallon, John
Publisher: name: Imperial College London
Year: 2019

description: Epigenetic changes are associated with the emergence of resistance to DNA damaging, anti-cancer drugs, such as cisplatin; widely used in the treatment of ovarian cancer. However, how chromatin conformation changes during the acquisition of resistance and how this influences cisplatin-DNA adduct formation are poorly understood. We have investigated chromatin conformation in matched sensitive and resistant ovarian cell lines, including lines isolated from high-grade serous ovarian cancer patients before and after the in vivo acquisition of platinum-resistance. ATAC-seq analysis reveals differences in chromatin conformation, with resistant lines showing variation in accessibility at intergenic regions. Furthermore, the loss or gain of super-enhancer elements in the resistant lines corresponded with altered expression of nearby genes. Using a novel assay, Pt-exo-seq, we show genome wide distribution of platinum-DNA adducts distinguish sensitive from resistant lines, even when inducing equivalent levels of platinum-DNA adducts and is associated with chromatin conformation changes and levels of gene expression. Repressed chromatin states were particularly pronounced in the regions showing increased adduct formation in the resistant line, with these regions being frequently intergenic and repetitive. Modulation of chromatin conformation using the HDAC inhibitor Vorinostat causes a global increase in conformation change and an overall increase in platinum-DNA adducts, concomitant with increased sensitivity to cisplatin. These data raise the suggestion that high platinum damage in repressed regions in resistant lines is a mechanism of cell survival in the presence of DNA-damage by acting as a “sink” for platinum molecules. We speculate that cells may tolerate cisplatin-DNA adducts at these sites through mechanisms which may potentiate the structural variation that is a defining feature of ovarian cancer. In combination with the potential for the repair of cisplatin-DNA adducts to induce epigenetic changes, these data provide a link between altered epigenetic states as a driver of drug resistance, the effect of chromatin conformation on DNA adduct distribution, and the epigenetic and genetic consequences of DNA damage and repair. These findings highlight altered genome distribution of platinum-DNA adducts as a key feature of resistant tumour cells and suggest the chemo-sensitising activity of chromatin modifying agents are related to their effect on levels of initial DNA damage and adduct distribution.
Dissecting Click Fraud Autonomy in the Wild
Creators: name: Zhu, Tong
name: Meng, Yan
name: Hu, Haotian
name: Zhang, Xiaokuan
name: Xue, Minhui
name: Zhu, Haojin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: Although the use of pay-per-click mechanisms stimulates the prosperity of the mobile advertisement network, fraudulent ad clicks result in huge financial losses for advertisers. Extensive studies identify click fraud according to click/traffic patterns based on dynamic analysis. However, in this study, we identify a novel click fraud, named humanoid attack, which can circumvent existing detection schemes by generating fraudulent clicks with similar patterns to normal clicks. We implement the first tool ClickScanner to detect humanoid attacks on Android apps based on static analysis and variational AutoEncoder (VAE) with limited knowledge of fraudulent examples. We define novel features to characterize the patterns of humanoid attacks in the apps' bytecode level. ClickScanner builds a data dependency graph (DDG) based on static analysis to extract these key features and form a feature vector. We then propose a classification model only trained on benign datasets to overcome the limited knowledge of humanoid attacks. We leverage ClickScanner to conduct the first large-scale measurement on app markets (i.e.,120,000 apps from Google Play and Huawei AppGallery) and reveal several unprecedented phenomena. First, even for the top-rated 20,000 apps, ClickScanner still identifies 157 apps as fraudulent, which shows the prevalence of humanoid attacks. Second, it is observed that the ad SDK-based attack (i.e., the fraudulent codes are in the third-party ad SDKs) is now a dominant attack approach. Third, the manner of attack is notably different across apps of various categories and popularities. Finally, we notice there are several existing variants of the humanoid attack. Additionally, our measurements demonstrate the proposed ClickScanner is accurate and time-efficient (i.e., the detection overhead is only 15.35% of those of existing schemes).
description: Accepted to ACM CCS 2021
On the Benefits of Decomposing Policy Engines into Components
Creators: name: Beznosov, Konstantin
Publisher: name: Zenodo
Year: 2005
Subjects: authorization
access control
Web services
policy
policy engines
RAD
object security attributes
Engineering Security Mechanisms

description: In order for middleware systems to be adaptive, their properties and services need to support a wide variety of application-specific policies. However, application developers and administrators should not be expected to cope with complex policy languages and evaluation engines or to develop custom engines from scratch. In this paper, we discuss the benefits of policy engines designed as component frameworks with a mix of parameterized pre-built and custom logic composed to implement complex policies. To provide an example of such a design approach, we present an authorization architecture for ASP.NET Web services that has been implemented in a real-world system.
X-MAS2: Study Systematics on the ICM Metallicity Measurements
Creators: name: Rasia, E.
name: Mazzotta, P.
name: Bourdin, H.
name: Borgani, S.
name: Tornatore, L.
name: Ettori, S.
name: Dolag, K.
name: Moscardini, L.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: (Abridged)The X-ray measurements of the ICM metallicity are becoming more frequent due to the availability of powerful X-ray telescope with excellent spatial and spectral resolutions. The information which can be extracted from the measurements of the alpha-elements, like Oxygen, Magnesium and Silicon with respect to the Iron abundance is extremely important to better understand the stellar formation and its evolutionary history. In this paper we investigate possible source of bias connected to the plasma physics when recovering metal abundances from X-ray spectra. To do this we analyze 6 simulated galaxy clusters processed through the new version of our X-ray MAp Simulator, which allows to create mock XMM-Newton EPIC MOS1 and MOS2 observations. By comparing the spectroscopic results to the input values we find that: i) Fe is recovered with high accuracy for both hot (T>3 keV) and cold (T<2 keV) systems; at intermediate temperatures, however, we find a systematic overestimate which depends on the number counts; ii) O is well recovered in cold clusters, while in hot systems its measure may overestimate by a factor up to 2-3; iii) Being a weak line, the measurement of Mg is always difficult; despite of this, for cold systems (T<2 keV) we do not find any systematic behavior, while for very hot systems (T>5 keV) the spectroscopic measurement may be strongly overestimated up to a factor of 4; iv) Si is well recovered for all the clusters in our sample. We investigate in detail the nature of the systematic effects and biases found. We conclude that they are mainly connected with the multi-temperature nature of the projected observed spectra and to the intrinsic limitation of the XMM-Newton EPIC spectral resolution that does not always allow to disentangle among the emission lines produced by different elements.
description: (e.g.: 17 pages, 8 figures, accepted for publication in the Astrophysical Journal, updated discussion to match published version-new section:6.3)
Board-er Games
Creators: name: Rossman, Sasha
Publisher: name: 21: Inquiries into Art, History, and the Visual
Year: 2025

description: This paper analyzes a seventeenth-century geographic board game designed by the geographer Pierre Duval (1618–1683) to celebrate the Peace of the Pyrenees in 1660. The game takes its players through the events of twenty-five years of war between France and Spain, staged largely along the perimeters of France. Contextualizing the game’s visual structure within the historical and semantic French discourse of borders allows us, I argue, to understand Duval’s object as an agent in border-building practices. These practices were neither located physically on France’s borders, nor were they top-down. Instead, Duval’s game suggests that a border imaginary could be constructed in the capital through collaborative operations in the form, for instance, of play. This border imaginary figured French state boundaries in the mid-seventeenth century as “frontiers” and, I suggest, this involved a gendered as well as a spatial dimension. When seeking to understand state formation and its mediation through visual culture, this paper implies, moreover, that seemingly trivial objects such as games which generally lie outside of the art historical cannon reveal themselves as a rich investigatory terrain.
description: 21: Inquiries into Art, History, and the Visual, Vol. 6 No. 1 (2025): 21: Inquiries into Art, History, and the Visual. Beiträge zur Kunstgeschichte und visuellen Kultur
Stochastic analysis of guided wave structural health monitoring for aeronautical composites
Creators: name: Yue, Nan
Publisher: name: Imperial College London
Year: 2019

description: This thesis presents new methods developed for improvement of the reliability of Guided Wave Structural Health Monitoring (GWSHM) systems for aeronautical composite. Particular attention is devoted to the detection and localisation of barely visible impact damage (BVID) in Carbon-Fibre Reinforced Polymer (CFRP) structures. A novel sensor installation method is developed that offers ease of application and replacement as well as excellent durability. Electromechanical Impedance (EMI) is used to assess the durability of the sensor installation methods in simulated aircraft operational conditions, including thermal cycles, fatigue loading and hot-wet conditions. The superiority of the developed method over existing installation methods is demonstrated through extensive tests. Damage characterisation using GWSHM is investigated in different CFRP structures. Key issues in guided wave based damage identification are addressed, including wave mode /frequency selection, the influence of dynamic load, the validity of simulated damage, sensitivity of guided wave to impact damage in different CFRP materials. Identification of barely visible impact damage (BVID) are investigated on three simple CFRP panels and two stiffened CFRP panels. BVID is detected using three different damage index and located using RAPID, Delay-and-sum, Rayleigh maximum likelihood estimation (RMLE) and Bayesian inference (BI). The influence of temperature on guided wave propagation in anisotropic CFRP structures is addressed and a novel baseline reconstruction approach for temperature compensation is proposed. The proposed temperature compensation method accommodates various sensor placement and can be established using coupon level structures for the application in larger scale structures. Finally, a multi-level hierarchical approach is proposed for the quantification of ultrasonic guided wave based structural health monitoring (GWSHM) system. The hierarchical approach provides a systemic and practical way of establishing GWSHM systems for different structures under uncertainties and assessing system performance. The proposed approach is demonstrated in aircraft CFRP structures from coupon level to sub-component level.
Empiric risk estimation in Alzheimer disease
Creators: name: Irwin, Mark Edward
Publisher: name: University of British Columbia
Year: 2010

description: Alzheimer disease is believed to be the most common cause of dementia. The main cause is presently unknown, with genetic and environmental factors suggested. It appears that 10-15% of Alzheimer disease is due to an autosomal dominant gene and it has been hypothesized that this is the cause for all Alzheimer's. Alzheimer's variable age of onset makes it more difficult to determine the validity of this and other genetic models. Empiric risk estimates for Alzheimer disease in relatives can used to test the plausibility of various genetic models. Three types of procedures for estimating the risk of Alzheimer disease are discussed. Three nonparametric, product-limit type estimators (Kaplan-Meier, Life-table, Weinberg) for age-specific risks are discussed first. Then three estimators for lifetime risk of disease using a predetermined weight function believed to approximate the true age of onset distribution (Stromgren, Modified Stromgren, maximum likelihood) are compared. Finally a maximum likelihood procedure to estimate lifetime risk and the age of onset distribution is presented. The properties of these estimators are discussed using a data set from the Alzheimer Clinic, University Hospital - U.B.C. Site. In addition, the results of a Monte-Carlo study of the maximum likelihood procedure for estimating the lifetime risk and age of onset distribution are discussed. The most useful of these estimators appear to be the Kaplan-Meier and the life-table estimators for age-specific risks and the maximum likelihood procedure for estimating lifetime risk and the age of onset distribution. The Weinberg estimator appears to be biased and the fixed age of onset estimators for lifetime risk appear to be too dependent on the choice of the age of onset distribution to be useful in general.
The effect of Saharan dust on the copper uptakeby Lemna minor
Creators: name: Rashidi, Adeleh
name: Ergen, Şeyda Fikirdeşici
name: Karakas, Mehmet
name: Saydam, Ahmet C.
name: Altındağ, Ahmet
Publisher: name: Polish Academy of Sciences
Year: 2019
Subjects: Lemna minor
Saharan dust
regression analysis
copper

description: Archives of Environmental Protection is the oldest Polish scientific journal of international scope that publishes articles on engineering and environmental protection. The quarterly has been published by the Institute of Environmental Engineering, Polish Academy of Sciences since 1975. The journal has served as a forum for the exchange of views and ideas among scientists. It has become part of scientific life in Poland and abroad. The quarterly publishes the results of research and scientific inquiries by best specialists hereby becoming an important pillar of science. The journal facilitates better understanding of environmental risks to humans and ecosystems and it also shows the methods for their analysis as well as trends in the search of effective solutions to minimize these risks. The journal is indexed by Thomson Reuters services (Biological Abstract, BIOSIS Previews) and has an Impact Factor 2017 of 1.120
description: In this study, the aim was to model the toxic effect of copper (Cu) and analyse the removal of Cu in aqueous Saharan and non-Saharan mediums by Lemna minor. Two separate test groups were formed: with Saharan dust (S) and without Saharan dust (WS). These test groups were exposed to 3 different Cu concentrations (0.05, 0.50 and 5.00 ppm). Time, concentration, and group-dependent removal efﬁ ciencies were compared using the non-parametric Mann-Whitney U test and statistically signiﬁ cant differences were found. The optimum removal values were tested at the highest concentration 79.6% in the S medium and observed on the 4th day for all test groups. The lowest removal value (16%) was observed at 0.50 ppm on the 1st day in the WS medium. When the S medium and WS medium were compared, in all test groups Cu was removed more successfully in the S medium than the WS medium contaminated by Cu in 3 different concentrations of (0.05 ppm, 0.50 ppm, 5.00 ppm). The regression analysis was also tested for all prediction models. Different models were performed and it was found that cubic models show the highest predicted values (R2). The R2 values of the estimation models were found to be at the interval of 0.939–0.991 in the WS medium and 0.995–1.000 in the S medium.
Self-consistent population spectral synthesis with FADO: II. Star formation history of galaxies in spectral synthesis methods
Creators: name: Pappalardo, Ciro
name: Cardoso, Leandro S. M.
name: Gomes, Jean Michel
name: Papaderos, Polychronis
name: Afonso, José
name: Breda, Iris
name: Humphrey, Andrew
name: Scott, Tom
name: Amarantidis, Stergios
name: Matute, Israel
name: Carvajal, Rodrigo
name: Lorenzoni, Silvio
name: Lagos, Patricio
name: Paulino-Afonso, Ana
name: Miranda, Henrique
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The field of galaxy evolution will make a great leap forward in the next decade as a consequence of the huge effort by the scientific community in multi-object spectroscopic facilities. To maximise the impact of such incoming data, the analysis methods must also step up, extracting reliable information from the available spectra. In this paper, we aim to investigate the limits and the reliability of different spectral synthesis methods in the estimation of the mean stellar age and metallicity. The main question this work aims to address is which signal-to-noise ratios (S/N) are needed to reliably determine the mean stellar age and metallicity from a galaxy spectrum and how this depends on the tool used to model the spectra. To address this question we built a set of realistic simulated spectra containing stellar and nebular emission, reproducing the evolution of a galaxy in two limiting cases: a constant star formation rate and an exponentially declining star formation. We degraded the synthetic spectra built from these two star formation histories (SFHs) to different S/N and analysed them with three widely used spectral synthesis codes, namely FADO, STECKMAP, and STARLIGHT. For S/N < 5 all three tools show a large diversity in the results. The FADO and STARLIGHT tools find median differences in the light-weighted mean stellar age of ~0.1 dex, while STECKMAP shows a higher value of ~0.2 dex. Detailed investigations of the best-fit spectrum for galaxies with overestimated mass-weighted quantities point towards the inability of purely stellar models to fit the observed spectra around the Balmer jump. Our results imply that when a galaxy enters a phase of high specific star formation rate the neglect of the nebular continuum emission in the fitting process has a strong impact on the estimation of its SFH when purely stellar fitting codes are used, even in presence of high S/N spectra.
description: New version matching the published one. 19 pages, 16 figures, accepted for publication in A&A
Innovative means of communicating research findings on Sustainable Development Goals
Creators: name: Barrantes, Barbara S. Lancho
Publisher: name: Zenodo
Year: 2021

description: Sustainable Development Goals have recently entered into our lives and made us to realise how important they are for the development of our society. With this work, I intend to show the trends in scholarly communication about Sustainable Development Goals using Dimensions database. Has there been a proliferation of Preprints? Alternatively, Journals continue occupying their star role? How open access means have performed on these issues. Has there been greater international cooperation? What comes after the SDGs? Can publications help us to figure this out?
Pure Point spectrum for measure dynamical systems on locally compact Abelian groups
Creators: name: Lenz, Daniel
name: Strungaru, Nicolae
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We show equivalence of pure point diffraction and pure point dynamical spectrum for measurable dynamical systems build from locally finite measures on locally compact Abelian groups. This generalizes all earlier results of this type. Our approach is based on a study of almost periodicity in a Hilbert space. It allows us to set up a perturbation theory for arbitrary equivariant measurable perturbations.
description: 22 pages
Optoelectronic Fingerprints of Interference between Different Charge Carriers in Graphene Superlattices and Analogies to Twisted Graphene Bilayers
Creators: name: Herrera, Saúl A.
name: Naumis, Gerardo G.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Motivated by recent experimental findings on the low-energy spectrum of Kekulé-patterned graphene, the optoelectronic signatures of graphene superlattices with a spatial modulation that triples the size of the unit cell and folds the valleys to the center of the Brillouin zone are studied. For superlattices like those visualized in recent experiments, the optoelectronic response reveals multiple species of carriers distinguished by their effective masses or Fermi velocities. Their signatures are similar to those of systems hosting multifold fermions in which different frequency intervals are dominated by different types of quasiparticles. Remarkably, the response of these systems exhibits a characteristic peak in the optical conductivity suggesting a kind of interference between the different species of carriers. We also discuss a related superlattice that exhibits merging Dirac cones and band flattening, with a Hamiltonian that resembles a version of the chiral model for twisted bilayer graphene where the long-range moiré modulation has been substituted by a two-parameter bias.
New binary pulsar constraints on Einstein-æther theory after GW170817
Creators: name: Gupta, Toral
name: Herrero-Valea, Mario
name: Blas, Diego
name: Barausse, Enrico
name: Cornish, Neil
name: Yagi, Kent
name: Yunes, Nicolás
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The timing of millisecond pulsars has long been used as an exquisitely precise tool for testing the building blocks of general relativity, including the strong equivalence principle and Lorentz symmetry. Observations of binary systems involving at least one millisecond pulsar have been used to place bounds on the parameters of Einstein-æther theory, a gravitational theory that violates Lorentz symmetry at low energies via a preferred and dynamical time threading of the spacetime manifold. However, these studies did not cover the region of parameter space that is still viable after the recent bounds on the speed of gravitational waves from GW170817/GRB170817A. The restricted coverage was due to limitations in the methods used to compute the pulsar sensitivities, which parameterize violations of the strong-equivalence principle in these systems. We extend here the calculation of pulsar sensitivities to the parameter space of Einstein-æther theory that remains viable after GW170817/GRB170817A. We show that observations of the damping of the period of quasi-circular binary pulsars and of the triple system PSR J0337+1715 further constrain the viable parameter space by about an order of magnitude over previous constraints.
description: 43 pages, 8 figures; minor changes to match version published in CQG
title: Unterstützungsleistungen im Kommunikationsraum Internet. Eine Fallstudie zu einer Selbsthilfegruppe. Dissertation. Universität Siegen
Creators: name: Barth, Stephan
Publisher: name: Universität Siegen
Year: 2011
Subjects: subject: 300 Sozialwissenschaften

description: Unterstützungsleistungen im Kommunikationsraum Internet. Eine Fallstudie zu einer Selbsthilfegruppe. Dissertation. Universität Siegen
NMR Evidence for Antiferromagnetic Transition in the Single-Component Molecular Conductor, [Au(tmdt)_{2}] at 110 K
Creators: name: Hara, Y.
name: Miyagawa, K.
name: Kanoda, K.
name: Shimamura, M.
name: Kobayashi, A.
name: Kobayashi, H.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present the results of a ^{1}H NMR study of the single-component molecular conductor, [Au(tmdt)_{2}]. A steep increase in the NMR line width and a peak formation of the nuclear spin-lattice relaxation rate, 1/T_{1}, were observed at around 110 K. This behavior provides clear and microscopic evidences for a magnetic phase transition at considerably high temperature among organic conductors. The observed variation in 1/T_{1} with respect to temperature indicates the highly correlated nature of the metallic phase.
description: 5pages, 6figures to be published in J. Phys. Soc. Jpn
Elliptic flow splittings in the Polyakov-looped Nambu-Jona Lasinio transport model
Creators: name: Zhou, Wen-Hao
name: Liu, He
name: Li, Feng
name: Sun, Yi-Feng
name: Xu, Jun
name: Ko, Che Ming
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: To incorporate the effect of gluons on the evolution dynamics of the quark matter produced in relativistic heavy-ion collisions, we extend the 3-flavor Nambu-Jona-Lasinio (NJL) transport model to include the contribution from the Polyakov loops. Imbedding the resulting pNJL partonic transport model in an extended multiphase transport (extended AMPT) model, we then study the elliptic flow splittings between particles and their antiparticles in relativistic heavy-ion collisions at RHIC-BES energies. We find that a weak quark vector interaction in the partonic phase is able to describe the elliptic flow splitting between protons and antiprotons in heavy-ion collisions at $\sqrt{s_{NN}}=7.7$ to 39 GeV. Knowledge on the quark vector interaction is useful for understanding the equation of state of quark matter at large baryon chemical potentials and thus the location of the critical point in the QCD phase diagram.
description: 14 pages, 15 figures
Perspectives on Institutional Capture and the Artification of Climate Activism
Creators: name: Militz, Marlene
Publisher: name: 21: Inquiries into Art, History, and the Visual
Year: 2025

description: The wave of staged art vandalism by climate activist groups in 2022 confronted museums with a dilemma: in their role as guardians of objects, they must prevent such actions, but in their function as forums for social discourse, they must be receptive to climate activism entering their spaces. To navigate this challenge, some museums have adopted a strategy of “institutional capture”, incorporating activism through “artification”. This article analyzes four examples from museums in the German-speaking realm that sought to legitimize activist interventions by recasting them as art-like – an on-demand aesthetic experience of protest or performative reenactment of direct action. However, the aim of this accommodation is twofold: to pacify activism and discourage similar incidents, while primarily reasserting the museum’s institutional legitimacy at a time of increasing erosion.
description: 21: Inquiries into Art, History, and the Visual, Vol. 6 No. 1 (2025): 21: Inquiries into Art, History, and the Visual. Beiträge zur Kunstgeschichte und visuellen Kultur
Preserving Monotonicity in Anisotropic Diffusion
Creators: name: Sharma, Prateek
name: Hammett, Gregory W.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: Computational Physics (physics.comp-ph)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: We show that standard algorithms for anisotropic diffusion based on centered differencing (including the recent symmetric algorithm) do not preserve monotonicity. In the context of anisotropic thermal conduction, this can lead to the violation of the entropy constraints of the second law of thermodynamics, causing heat to flow from regions of lower temperature to higher temperature. In regions of large temperature variations, this can cause the temperature to become negative. Test cases to illustrate this for centered asymmetric and symmetric differencing are presented. Algorithms based on slope limiters, analogous to those used in second order schemes for hyperbolic equations, are proposed to fix these problems. While centered algorithms may be good for many cases, the main advantage of limited methods is that they are guaranteed to avoid negative temperature (which can cause numerical instabilities) in the presence of large temperature gradients. In particular, limited methods will be useful to simulate hot, dilute astrophysical plasmas where conduction is anisotropic and the temperature gradients are enormous, e.g., collisionless shocks and disk-corona interface.
description: accepted for publication in J. of Comp. Phys
Johann Moritz Rugendas’ “Voyage pittoresque dans le Brésil”
Creators: name: Gaete, Miguel
Publisher: name: 21: Inquiries into Art, History, and the Visual
Year: 2025

description: Johann Moritz Rugendas (1802–1858) is widely regarded as one of the most significant Romantic European painters in nineteenth-century Latin America. His extensive body of work, which includes thousands of drawings, lithographic albums, and hundreds of paintings, establishes him as one of the most prolific artists to explore and portray the continent. In 1822, Rugendas embarked on an almost three-year journey across Brazil, depicting its people and landscapes. The primary outcome of this journey was his celebrated Picturesque Voyage in Brazil, published between 1826 and 1835 in French and German. Hitherto, Voyage pittoresque has been viewed as a critique of the slave trade, positioning Rugendas as an advocate for racial equality. However, this article argues that Rugendas’ portrayal of slavery reveals an ambiguous and inconsistent stance on racial issues, complicating the narrative of a fierce denouncer of slavery built around his figure. Through detailed analysis of the album’s texts and images and foregrounding overlooked evidence, this essay challenges the notion of the volume as an antislavery manifesto, highlighting its racialist undertones and the complex interplay of pain, pleasure, the picturesque, and the sublime.
description: 21: Inquiries into Art, History, and the Visual, Vol. 6 No. 1 (2025): 21: Inquiries into Art, History, and the Visual. Beiträge zur Kunstgeschichte und visuellen Kultur
A universal procedure for aggregating estimators
Creators: name: Goldenshluger, Alexander
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: 62G08 (Primary) 62G05, 62G20 (Secondary)

description: In this paper we study the aggregation problem that can be formulated as follows. Assume that we have a family of estimators $\mathcal{F}$ built on the basis of available observations. The goal is to construct a new estimator whose risk is as close as possible to that of the best estimator in the family. We propose a general aggregation scheme that is universal in the following sense: it applies for families of arbitrary estimators and a wide variety of models and global risk measures. The procedure is based on comparison of empirical estimates of certain linear functionals with estimates induced by the family $\mathcal{F}$. We derive oracle inequalities and show that they are unimprovable in some sense. Numerical results demonstrate good practical behavior of the procedure.
description: Published in at http://dx.doi.org/10.1214/00-AOS576 the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Low-surface-brightness spheroidal galaxies as Milgromian isothermal spheres
Creators: name: Sanders, R. H.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: I consider a sample of eight pressure-supported low-surface brightness galaxies in terms of Milgrom's modified Newtonian dynamics (MOND). These objects include seven nearby dwarf spheroidal galaxies -- Sextans, Carina, Leo II, Sculptor, Draco, Leo I, Fornax, and the ultra-diffuse galaxy DF44. The objects are modelled as Milgromian isotropic isothermal spheres characterised by two parameters that are constrained by observations: the constant line-of-sight velocity dispersion and the central surface density. The velocity dispersion determines the total mass, and, with the implied mass-to-light ratio, the central surface brightness. This then specifies the radial run of surface brightness over the entire isothermal sphere. For these objects the predicted radial distribution of surface brightness is shown to be entirely consistent with observations. This constitutes a success for MOND that is independent of the reduced dynamical mass.
description: 7 pages, 4 figures, minor errors in Table 1 corrected
A New Sample of Low-mass Black Holes in Active Galaxies
Creators: name: Greene, Jenny E.
name: Ho, Luis C.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present an expanded sample of low-mass black holes (BHs) found in galactic nuclei. Using standard virial mass techniques to estimate BH masses, we select from the Fourth Data Release of the Sloan Digital Sky Survey all broad-line active galaxies with masses < 2 x 10^6 M_sun. BHs in this mass regime provide unique tests of the relationship between BHs and galaxies, since their late-type galaxy hosts do not necessarily contain classical bulges. Furthermore, they provide observational analogs of primordial seed BHs and are expected, when merging, to provide strong gravitational signals for future detectors such as LISA. From our preliminary sample of 19, we have increased the total sample by an order of magnitude to 174, as well as an additional 55 (less secure) candidates. The sample has a median BH mass of = 1.3 x 10^6 M_sun, and in general the objects are radiating at high fractions of their Eddington limits. We investigate the broad spectral properties of the sample; 55 are detected by \rosat, with soft X-ray luminosities in the range 10^40 to 7 x 10^43 ergs/sec. Much like the preliminary sample, these objects are predominantly radio-quiet (R = f_6cm/f_4400A < 10), but 11 objects are detected at 20 cm, with radio powers (10^21-10^23 W/Hz) that may arise from either star formation or nuclear activity; only 1% of the sample is radio-loud. We further confirm that, with =-19.3 and = 0.7 mag, the host galaxies are low-mass, late-type systems. At least 40% show disk-like morphologies, and the combination of host galaxy colors and higher-order Balmer absorption lines indicate intermediate-age stellar populations in a subset of the sample.
description: to appear in ApJ; 13 pages, 8 figures
Baryon number non-conservation as Peccei-Quinn mechanism
Creators: name: Ohata, Takahiro
name: Takeuchi, Kengo
name: Tsumura, Koji
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Baryon number is an accidental symmetry in the standard model, while Peccei-Quinn symmetry is hypothetical symmetry which is introduced to solve the strong CP problem. We study the possible connections between Peccei-Quinn symmetry and baryon number symmetry. In this framework, an axion is identified as the Nambu-Goldstone boson of baryon number violation. As a result, characteristic baryon number violating processes are predicted. We developed the general method to determine the baryon number and lepton number of new scalar in the axion model.
description: 19 pages, 6 figures, version accepted in PRD
An economic impact assessment of the Chilliwack region using an input-output model
Creators: name: Heikkila, Richard Aarne
Publisher: name: University of British Columbia
Year: 2010

description: Input-output (I-O) analysis is a technique to model the structure and inter-sectoral flows of an economy. The I-O model can further be used to estimate the magnitude of backward-linked economic activity (indirect and induced effects), and the effect of an increase or decrease in final demand. As well, the model can assess the effect of certain government policies on the output, income, and resource use of regions. In this study, the conceptual and mathematical frameworks of I-O analysis are explained in detail. Technical considerations relating to the construction and operation of regional I-O models are also reviewed. An I-O model of the Chilliwack region is constructed. The structure of the Chilliwack regional economy is evaluated; multiplier estimates of regional sectors are derived; and the response of the Chilliwack economy to specific changes in final demand is simulated.
A Geometrical Method for the Smoluchowski Equation on the Sphere
Creators: name: Gómez, Adriano Valdés
name: Sevilla, Francisco J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: A study of the diffusion of a passive Brownian particle on the surface of a sphere and subject to the effects of an external potential, coupled linearly to the probability density of the particle's position, is presented through a numerical algorithm devised to simulate the trajectories of an ensemble of Brownian particles. The algorithm is based on elementary geometry and practically only algebraic operations are used, which makes the algorithm efficient and simple, and converges, in the \textit{weak sense}, to the solutions of the Smoluchowski equation on the sphere. Our findings show that the global effects of curvature are taken into account in both the time dependent and stationary processes.
description: Diffusion of a Brownian particle on the sphere surface under external potentials. 11 pages, 8 figures
Competing itinerant and localized states in strongly correlated BaVS$_3$
Creators: name: Lechermann, Frank
name: Biermann, Silke
name: Georges, Antoine
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The electronic structure of the quasi-lowdimensional vanadium sulfide \bavs3 is investigated for the different phases above the magnetic ordering temperature. By means of density functional theory and its combination with dynamical-mean field theory, we follow the evolution of the relevant low-energy electronic states on cooling. Hence we go in the metallic regime from the room temperature hexagonal phase to the orthorhombic phase after the first structural transition, and close with the monoclinic insulating phase below the metal-insulator transition. Due to the low symmetry and expected intersite correlations, the latter phase is treated within cellular dynamical mean-field theory. It is generally discussed how the intriguing interplay between band-structure and strong-correlation effects leads to the stabilization of the various electronic phases with decreasing temperature.
description: 12 pages, submitted to PRB
Overview of Reference Model of Open Distributed Processing (RM-ODP)
Creators: name: Beznosov, Konstantin
Publisher: name: Zenodo
Year: 2005
Subjects: RM-ODP
Viewpoints
enterprise modeling
etc.

description: Outline: - Why Languages for Enterprises? - Introduction - RM-ODP goal - What it de nes - Viewpoints - Modeling in RM-ODP - Languages - Analysis of RM-ODP - Summary - Additional Information
Domino Waves
Creators: name: Efthimiou, C. J.
name: Johnson, M. D.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Dynamical Systems (math.DS)
subject: History and Overview (math.HO)
subject: FOS: Mathematics
subject: 70B99, 70F35, 97A90

description: Motivated by a proposal of Daykin (Problem 71-19*, SIAM Review 13 (1971) 569), we study the wave that propagates along an infinite chain of dominoes and find the limiting speed of the wave in an extreme case.
description: 10 pages, 5 figures