cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
A Unique Perfect Power Decagonal Number
Creators: name: Michaud-Rodgers, Philippe
Publisher: name: arXiv
Year: 2021
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11D41, 11G99

description: Let $\mathcal{P}_s(n)$ denote the $n$th $s$-gonal number. We consider the equation \[\mathcal{P}_s(n) = y^m, \] for integers $n,s,y,$ and $m$. All solutions to this equation are known for $m>2$ and $s \in \{3,5,6,8,20 \}$. We consider the case $s=10$, that of decagonal numbers. Using a descent argument and the modular method, we prove that the only decagonal number $>1$ expressible as a perfect $m$th power with $m>1$ is $\mathcal{P}_{10}(3) = 3^3$.
description: 5 pages. Some typos corrected
Deconfining the rotational Goldstone mode: the superconducting nematic liquid crystal in 2+1D
Creators: name: Beekman, Aron J.
name: Wu, Kai
name: Cvetkovic, Vladimir
name: Zaanen, Jan
Publisher: name: arXiv
Year: 2013
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The Goldstone theorem states that there should be a massless mode for each spontaneously broken symmetry generator. There is no such rotational mode in crystals, however superconducting quantum nematics should carry rotational Goldstone modes. By generalization of thermal 2D defect mediated melting theory into a 2+1D quantum duality, the emergence of the rotational mode at the quantum phase transition from the solid to the nematic arises as a deconfinement phenomenon, with the unusual property that the stiffness of the rotational mode originates entirely in the dual dislocation condensate.
description: 5 pages
Simple Complex Tori of Algebraic Dimension 0
Creators: name: Bandman, Tatiana
name: Zarhin, Yuri G.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Algebraic Geometry (math.AG)
subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 32M05, 32J18, 32J27, 14J50

description: Using Galois theory, we construct explicitly (in all complex dimensions >1) an infinite family of simple complex tori of algebraic dimension 0 with Picard number 0.
description: 22 pages. arXiv admin note: substantial text overlap with arXiv:2103.07015
Impact of the Nuclear Modification of the Gluon Densities on J/Psi production in pPb collisions at sqrt(s_NN) = 5 TeV
Creators: name: Ferreiro, E. G.
name: Fleuret, F.
name: Lansberg, J. P.
name: Rakotozafindrabe, A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We update our previous studies of nuclear-matter effects on J/Psi production in proton-nucleus for the recent LHC pPb runs at sqrt(s_NN)=5 TeV. We have analysed the effects of the modification of the gluon PDFs in nucleus, using an exact kinematics for a 2->2 process, namely g+g->J/Psi+g as expected from LO pQCD. This allows to constrain the transverse-momentum while computing the nuclear modification factor for different rapidities, unlike with the usual simplified kinematics. Owing to the absence of measurement in pp collisions at the same sqrt(s_NN) and owing to the expected significant uncertainties in yield interpolations which would hinder definite interpretations of nuclear modification factor --R_pPb--, we have derived forward-to-backward and central-to-peripheral yield ratios in which the unknown proton-proton yield cancel. These have been computed without and with a transverse-momentum cut, e.g. to comply with the ATLAS and CMS constraints in the central-rapidity region.
description: 5 pages, 16 figures, LaTeX. v2: predictions on R_CP and 3 references added; introduction slightly extended
Finitely generated subgroups of free groups as formal languages and their cogrowth
Creators: name: Darbinyan, Arman
name: Grigorchuk, Rostislav
name: Shaikh, Asif
Publisher: name: arXiv
Year: 2021
Subjects: subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 20E07, 68Q45, 68Q70

description: For finitely generated subgroups $H$ of a free group $F_m$ of finite rank $m$, we study the language $L_H$ of reduced words that represent $H$ which is a regular language. Using the (extended) core of Schreier graph of $H$, we construct the minimal deterministic finite automaton that recognizes $L_H$. Then we characterize the f.g. subgroups $H$ for which $L_H$ is irreducible and for such groups explicitly construct ergodic automaton that recognizes $L_H$. This construction gives us an efficient way to compute the cogrowth series $L_H(z)$ of $H$ and entropy of $L_H$. Several examples illustrate the method and a comparison is made with the method of calculation of $L_H(z)$ based on the use of Nielsen system of generators of $H$.
description: 35 pages, 8 figures, revised version, to appear in journal of Groups, Complexity and Cryptology
Reduction of turbulent skin-friction drag by passively rotating discs
Creators: name: Olivucci, Paolo
name: Wise, Daniel J.
name: Ricco, Pierre
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: A turbulent channel flow modified by the motion of discs that are free to rotate under the action of wall turbulence is studied numerically. The Navier-Stokes equations are coupled nonlinearly with the dynamical equation of the disc motion, which synthesizes the fluid-flow boundary conditions and is driven by the torque exerted by the wall-shear stress. We consider discs that are fully exposed to the fluid and discs for which only half of the surface interfaces the fluid. The disc motion is thwarted by the fluid torque in the housing cavity and by the torque of the ball bearing that supports the disc. For the full discs, no drag reduction occurs because of the small angular velocities. The most energetic disc response occurs for disc diameters that are comparable with the spanwise spacing of the low-speed streaks. A perturbation analysis for small disc-tip velocities reveals that the two-way nonlinear coupling has an intense attenuating effect on the disc response. The reduced-order results show excellent agreement with the nonlinear results for large diameters. The half discs rotate with a finite angular velocity, leading to large reduction of the turbulence activity and of the skin-friction drag over the spinning portion of the discs, while the maximum drag reduction over the entire walls is 5.6%. The dependence of the drag reduction on the wall-slip velocity and the spatial distribution of the wall-shear stress qualitatively match results based on the only available experimental data.
description: Accepted for publication in J. Fluid Mech
Designing and interpreting ‘multi-omic’ experiments that may change our understanding of biology
Creators: name: Haas, Robert
name: Zelezniak, Aleksej
name: Iacovacci, Jacopo
name: Kamrad, Stephan
name: Townsend, StJohn
name: Ralser, Markus
Publisher: name: The Francis Crick Institute
Year: 2021
Subjects: Synthetic Biology
Chemical Biology & High Throughput
Ecology,Evolution & Ethology
Metabolism
Computational & Systems Biology

description: Most biological mechanisms involve more than one type of biomolecule, and hence operate not solely at the level of either genome, transcriptome, proteome, metabolome or ionome. Datasets resulting from single-omic analysis are rapidly increasing in throughput and quality, rendering multi-omic studies feasible. These should offer a comprehensive, structured and interactive overview of a biological mechanism. However, combining single-omic datasets in a meaningful manner has so far proved challenging, and the discovery of new biological information lags behind expectation. One reason is that experiments conducted in different laboratories can typically not to be combined without restriction. Second, the interpretation of multi-omic datasets represents a significant challenge by nature, as the biological datasets are heterogeneous not only for technical, but also for biological, chemical, and physical reasons. Here, multi-layer network theory and methods of artificial intelligence might contribute to solve these problems. For the efficient application of machine learning however, biological datasets need to become more systematic, more precise - and much larger. We conclude our review with basic guidelines for the successful set-up of a multi-omic experiment.
Affine completeness of some free binary algebras
Creators: name: Arnold, André
name: Cégielski, Patrick
name: Guessarian, Irène
Publisher: name: arXiv
Year: 2021
Subjects: subject: Rings and Algebras (math.RA)
subject: Formal Languages and Automata Theory (cs.FL)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: F.4.m
subject: 06A99 - 08A30 - 08B20

description: A function on an algebra is congruence preserving if, for any congruence, it maps pairs of congruent elements onto pairs of congruent elements. An algebra is said to be affine complete if every congruence preserving function is a polynomial function. We show that the algebra of (possibly empty) binary trees whose leaves are labeled by letters of an alphabet containing at least one letter, and the free monoid on an alphabet containing at least two letters are affine complete.
description: 18 pages
Global energy budgets in turbulent Couette and Poiseuille flows
Creators: name: Andreolli, Andrea
name: Quadrio, Maurizio
name: Gatti, Davide
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Turbulent plane Poiseuille and Couette flows share the same geometry, but produce their flow rate owing to different external drivers, pressure gradient and shear respectively. By looking at integral energy fluxes, we pose and answer the question of which flow performs better at creating flow rate. We define a flow {\em efficiency}, that quantifies the fraction of power used to produce flow rate instead of being wasted as a turbulent overhead; {\em effectiveness}, instead, describes the amount of flow rate produced by a given power. The work by Gatti \emph{et al.} (\emph{J. Fluid Mech.} vol.857, 2018, pp. 345--373), where the constant power input (CPI) concept was developed to compare turbulent Poiseuille flows with drag reduction, is here extended to compare different flows. By decomposing the mean velocity field into a laminar contribution and a deviation, analytical expressions are derived which are the energy-flux equivalents of the FIK identity. These concepts are applied to literature data supplemented by a new set of direct numerical simulations, to find that Couette flows are less efficient but more effective than Poiseuille ones. The reason is traced to the more effective laminar component of Couette flows, which compensates for their higher turbulent activity. It is also observed that, when the fluctuating fields of the two flows are fed with the same total power fraction, Couette flows dissipate a smaller percentage of it via turbulent dissipation. A decomposition of the fluctuating field into large and small scales explains this feature: Couette flows develop stronger large-scale structures, which alter the mean flow while contributing less significantly to dissipation.
The Complexity of Synthesis of $b$-Bounded Petri Nets
Creators: name: Tredup, Ronny
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Complexity (cs.CC)
subject: FOS: Computer and information sciences

description: For a fixed type of Petri nets $τ$, \textsc{$τ$-Synthesis} is the task of finding for a given transition system $A$ a Petri net $N$ of type $τ$ ($τ$-net, for short) whose reachability graph is isomorphic to $A$ if there is one. The decision version of this search problem is called \textsc{$τ$-Solvability}. If an input $A$ allows a positive decision, then it is called $τ$-solvable and a sought net $N$ $τ$-solves $A$. As a well known fact, $A$ is $τ$-solvable if and only if it has the so-called $τ$-\emph{event state separation property} ($τ$-ESSP, for short) and the $τ$-\emph{state separation property} ($τ$-SSP, for short). The question whether $A$ has the $τ$-ESSP or the $τ$-SSP defines also decision problems. In this paper, for all $b\in \mathbb{N}$, we completely characterize the computational complexity of \textsc{$τ$-Solvability}, \textsc{$τ$-ESSP} and \textsc{$τ$-SSP} for the types of pure $b$-bounded Place/Transition-nets, the $b$-bounded Place/Transition-nets and their corresponding $\mathbb{Z}_{b+1}$-extensions.
Effect of disorder in the charge-density-wave compounds LaTe$_{1.95}$ and CeTe$_{1.95-x}$Se$_x$ (x=0 and 0.16) as revealed by optical spectroscopy
Creators: name: Huang, Y.
name: Hu, B. F.
name: Dong, T.
name: Fang, A. F.
name: Zheng, P.
name: Wang, N. L.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present optical spectroscopy measurements on rare-earth ditelluride single crystals of LaTe$_{1.95}$ and CeTe$_{1.95-x}$Se$_x$ (x=0 and 0.16). The measurements reveal formation of charge density wave energy gaps at rather high energy levels, e.g. 2$Δ\sim$ 8500 \cm for LaTe$_{1.95}$, and 6800 \cm for CeTe$_{1.95}$. More strikingly, the study reveals that, different from the rare-earth tri-tellurides, the Te vacancies and disorder effect play a key role in the low-energy charge excitations of ditelluride systems. Although an eminent peak is observed between 800 and 1500 \cm in conductivity spectra for LaTe$_{1.95}$, and CeTe$_{1.95-x}$Se$_x$ (x=0. 0.16), our analysis indicates that it could not be attributed to the formation of a small energy gap, instead it could be well accounted for by the localization modified Drude model. Our study also indicates that the low-tempreature optical spectroscopic features are distinctly different from a semiconducting CDW state with entirely gapped Fermi surfaces.
description: 5 pages, 4 figures, Accepted for publication in Phys. Rev. B
Alignment-dependent fluorescence emission induced by tunnel ionization of carbon dioxide from lower-lying orbitals
Creators: name: Yao, Jinping
name: Li, Guihua
name: Jia, Xinyan
name: Hao, Xiaolei
name: Zeng, Bin
name: Jing, Chenrui
name: Chu, Wei
name: Ni, Jielei
name: Zhang, Haisu
name: Xie, Hongqiang
name: Zhang, Chaojin
name: Zhao, Zengxiu
name: Chen, Jing
name: Liu, Xiaojun
name: Cheng, Ya
name: Xu, Zhizhan
Publisher: name: arXiv
Year: 2013
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Study on ionization process of molecules in an intense infrared laser field is of paramount interest in strong-field physics and constitutes the foundation of imaging of molecular valence orbitals and attosecond science. We show measurement of alignment-dependent ionization probabilities of the lower-lying orbitals of the molecules by experimentally detecting alignment-dependence of fluorescence emission from tunnel ionized carbon dioxide molecules. The experimental measurements are compared with the theoretical calculations of strong field approximation (SFA) and molecular ADK models. Our results demonstrate the feasibility of an all-optical approach for probing the ionization dynamics of lower-lying orbitals of molecules, which is still difficult to achieve until now by other techniques. Moreover, the deviation between the experimental and theoretical results indicates the incompleteness of current theoretical models for describing strong field ionization of molecules.
description: 22 pages, 4 figures
Thermopower and the Mott formula for a Majorana edge state
Creators: name: Hou, Chang-Yu
name: Shtengel, Kirill
name: Refael, Gil
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We study the thermoelectric effect between a conducting lead and a Majorana edge state. In the tunneling limit, we first use the Landuaer-Buttiker formalism to derive the Mott formula relating the thermopower and the differential conductance between a conducting lead and a superconductor. When the tunneling takes place between a conducting lead and a Majorana edge state, we show that a non-vanishing thermopower can exist. Combining measurements of the differential conductance and the voltage difference induced by the temperature difference between the conducting lead and the edge state, the Mott formula provides a unique way to infer the temperature of the Majorana edge state.
description: 9 pages, 3 figures
Die Stadthalle Dietikon
Creators: name: Fürst, Max
name: Hensler, Josef
name: Schildknecht, Oskar
name: Schnüriger, Xaver
name: Siegrist, Reto
name: Zumbühl, Max
name: Hummel, Oscar
Publisher: name: Druckerei Hummel
Year: 2006
Subjects: subject: 725 Öffentliche Bauwerke
subject: 790 Freizetgestaltung, darstellende Künste, Sport
subject: 949 Geschichte anderer Teile Europas
subject: Dietikon
subject: Genossenschaft Stadthalle Dietikon
subject: Stadthalle
subject: Veranstaltungshalle

description: Mit einer Jahreschronik für Dietikon von Oktober 2004 bis September 2005.
description: Inhalt: 1. Von der Idee bis zur Eröffnung ; Entstehung, Konzept und Infrastruktur der ersten Halle ; Notwendige Verbesserungen und Sanierungen ; Vermietung und Tarife ; Finanzen ; Veranstaltungs-Highlights ; Highlights der anderen Art ; Der Sport - Grundpfeiler der Auslastung ; Millionenschaden nach Vollbrand ; Neubau der Stadthalle Dietikon - Rahmenbedingungen mit Tücken ; Das Dach der Stadthalle als Wärmespender ; Die Neueröffnung ; Die neue Stadthalle von Dietikon ; Die Väter und Betreuer der Halle ; Die Zukunft der Halle.
Mächtige Fürstinnen – fromme Stifterinnen? Das Stiftungsverhalten der Tiroler Landesfürstinnen (13. und 14. Jahrhundert)
Creators: name: Hörmann-Thurn Und Taxis, Julia
Publisher: name: Vorträge und Forschungen
Year: 2018

description: -
description: Vorträge und Forschungen, Bd. 81 (2015): Vorträge und Forschungen: Mächtige Frauen?
Oncogenic PIK3CA induces centrosome amplification and tolerance to genome doubling
Creators: name: Berenjeno, Inma M
name: Piñeiro, Roberto
name: Castillo, Sandra D
name: Pearce, Wayne
name: McGranahan, Nicholas
name: Dewhurst, Sally M
name: Meniel, Valerie
name: Birkbak, Nicolai J
name: Lau, Evelyn
name: Sansregret, Laurent
name: Morelli, Daniele
name: Kanu, Nnennaya
name: Srinivas, Shankar
name: Graupera, Mariona
name: Parker, Victoria ER
name: Montgomery, Karen G
name: Moniz, Larissa S
name: Scudamore, Cheryl L
name: Phillips, Wayne A
name: Semple, Robert K
name: Clarke, Alan
name: Swanton, Charles
name: Vanhaesebroeck, Bart
Publisher: name: The Francis Crick Institute
Year: 2021
Subjects: Tumour Biology
Signalling & Oncogenes
Genetics & Genomics
Genome Integrity & Repair
Human Biology & Physiology
Chemical Biology & High Throughput
Ecology,Evolution & Ethology
Computational & Systems Biology

description: Mutations in PIK3CA are very frequent in cancer and lead to sustained PI3K pathway activation. The impact of acute expression of mutant PIK3CA during early stages of malignancy is unknown. Using a mouse model to activate the Pik3ca H1047R hotspot mutation in the heterozygous state from its endogenous locus, we here report that mutant Pik3ca induces centrosome amplification in cultured cells (through a pathway involving AKT, ROCK and CDK2/Cyclin E-nucleophosmin) and in mouse tissues, and increased in vitro cellular tolerance to spontaneous genome doubling. We also present evidence that the majority of PIK3CA H1047R mutations in the TCGA breast cancer cohort precede genome doubling. These previously unappreciated roles of PIK3CA mutation show that PI3K signalling can contribute to the generation of irreversible genomic changes in cancer. While this can limit the impact of PI3K-targeted therapies, these findings also open the opportunity for therapeutic approaches aimed at limiting tumour heterogeneity and evolution.
Automated Repair of Process Models with Non-Local Constraints Using State-Based Region Theory
Creators: name: Kalenkova, Anna
name: Carmona, Josep
name: Polyvyanyy, Artem
name: La Rosa, Marcello
Publisher: name: arXiv
Year: 2021
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Formal Languages and Automata Theory (cs.FL)
subject: FOS: Computer and information sciences

description: State-of-the-art process discovery methods construct free-choice process models from event logs. Consequently, the constructed models do not take into account indirect dependencies between events. Whenever the input behaviour is not free-choice, these methods fail to provide a precise model. In this paper, we propose a novel approach for enhancing free-choice process models by adding non-free-choice constructs discovered a-posteriori via region-based techniques. This allows us to benefit from the performance of existing process discovery methods and the accuracy of the employed fundamental synthesis techniques. We prove that the proposed approach preserves fitness with respect to the event log while improving the precision when indirect dependencies exist. The approach has been implemented and tested on both synthetic and real-life datasets. The results show its effectiveness in repairing models discovered from event logs.
A. Furtwängler, Der Goldfund von Vettersfelde, 43. Programm zum Winckelmannsfeste der archäolog. Gesellschaft zu Berlin
Creators: name: Schaaffhausen, Hermann
Publisher: name: Bonner Jahrbücher
Year: 2018

description: Rezension zu: A. Furtwängler, Der Goldfund von Vettersfelde, 43. Programm zum Winckelmannsfeste der archäolog. Gesellschaft zu Berlin, mit 3 Tafeln, 1883. 4.
description: Bonner Jahrbücher, Bd. 77 (1884): Jahrbücher des Vereins von Altertumsfreunden im Rheinlande
On Completeness of Cost Metrics and Meta-Search Algorithms in $-Calculus
Creators: name: Eberbach, Eugene
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Complexity (cs.CC)
subject: Logic in Computer Science (cs.LO)
subject: FOS: Computer and information sciences

description: In the paper we define three new complexity classes for Turing Machine undecidable problems inspired by the famous Cook/Levin's NP-complete complexity class for intractable problems. These are U-complete (Universal complete), D-complete (Diagonalization complete) and H-complete (Hypercomputation complete) classes. In the paper, in the spirit of Cook/Levin/Karp, we started the population process of these new classes assigning several undecidable problems to them. We justify that some super-Turing models of computation, i.e., models going beyond Turing machines, are tremendously expressive and they allow to accept arbitrary languages over a given alphabet including those undecidable ones. We prove also that one of such super-Turing models of computation - the \$-Calculus, designed as a tool for automatic problem solving and automatic programming, has also such tremendous expressiveness. We investigate also completeness of cost metrics and meta-search algorithms in \$-calculus.
Franz Xaver Kraus, Die christlichen Inschriften der Rheinlande. Erster Theil: Die altchristlichen Inschriften von den Anfängen des Christenthums am Rhein bis zur Mitte des achten Jahrhunderts
Creators: name: Ihm, Max
Publisher: name: Bonner Jahrbücher
Year: 2018

description: Rezension zu: Franz Xaver Kraus, Die christlichen Inschriften der Rheinlande. Erster Theil: Die altchristlichen Inschriften von den Anfängen des Christenthums am Rhein bis zur Mitte des achten Jahrhunderts. Mit 22 Lichtdrucktafeln und zahlreichen in den Text gedruckten Abbildungen. Freiburg i. B. 1890. Akademische Buchhandlung von J. C. B. Mohr (Paul Siebeck). 4°.
description: Bonner Jahrbücher, Bd. 90 (1891): Jahrbücher des Vereins von Alterthumsfreunden im Rheinlande
Delta-Notch signalling in segmentation
Creators: name: Liao, Bo-Kai
name: Oates, Andrew C
Publisher: name: The Francis Crick Institute
Year: 2021
Subjects: Model organisms
Synthetic Biology
Imaging
Signalling & Oncogenes
Gene Expression
Developmental Biology
Microfabrication & Bioengineering
Computational & Systems Biology

description: Modular body organization is found widely across multicellular organisms, and some of them form repetitive modular structures via the process of segmentation. It's vastly interesting to understand how these regularly repeated structures are robustly generated from the underlying noise in biomolecular interactions. Recent studies from arthropods reveal similarities in segmentation mechanisms with vertebrates, and raise the possibility that the three phylogenetic clades, annelids, arthropods and chordates, might share homology in this process from a bilaterian ancestor. Here, we discuss vertebrate segmentation with particular emphasis on the role of the Notch intercellular signalling pathway. We introduce vertebrate segmentation and Notch signalling, pointing out historical milestones, then describe existing models for the Notch pathway in the synchronization of noisy neighbouring oscillators, and a new role in the modulation of gene expression wave patterns. We ask what functions Notch signalling may have in arthropod segmentation and explore the relationship between Notch-mediated lateral inhibition and synchronization. Finally, we propose open questions and technical challenges to guide future investigations into Notch signalling in segmentation.
Addressing Machines as models of lambda-calculus
Creators: name: Della Penna, Giuseppe
name: Intrigila, Benedetto
name: Manzonetto, Giulio
Publisher: name: arXiv
Year: 2021
Subjects: subject: Logic in Computer Science (cs.LO)
subject: FOS: Computer and information sciences

description: Turing machines and register machines have been used for decades in theoretical computer science as abstract models of computation. Also the $λ$-calculus has played a central role in this domain as it allows to focus on the notion of functional computation, based on the substitution mechanism, while abstracting away from implementation details. The present article starts from the observation that the equivalence between these formalisms is based on the Church-Turing Thesis rather than an actual encoding of $λ$-terms into Turing (or register) machines. The reason is that these machines are not well-suited for modelling $λ$-calculus programs. We study a class of abstract machines that we call "addressing machine" since they are only able to manipulate memory addresses of other machines. The operations performed by these machines are very elementary: load an address in a register, apply a machine to another one via their addresses, and call the address of another machine. We endow addressing machines with an operational semantics based on leftmost reduction and study their behaviour. The set of addresses of these machines can be easily turned into a combinatory algebra. In order to obtain a model of the full untyped $λ$-calculus, we need to introduce a rule that bares similarities with the $ω$-rule and the rule $ζ_β$ from combinatory logic.
Comparative Effects of Cattail Paludiculture and Dairy Farming on Arthropod Diversity
Creators: name: Adam, Moritz Michel
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 379901
subject: Earth system sciences
classificationCode: 410604
subject: Soil chemistry and soil carbon sequestration (excl. carbon sequestration science)
classificationCode: 350201
subject: Environment and climate finance

description: European environmental policies have recently recognized the potential of paludiculture for reducing greenhouse gas emissions from the agricultural sector. However, current research on paludiculture mainly concentrates on emission balance and crop productivity without considering effects on biodiversity. To contribute towards filling this knowledge gap this thesis compared arthropod abundance, taxonomic richness, and community composition between drained peatlands used for dairy production and Typha spp. paludiculture farms. In addition, environmental variables - such as water level, soil-, and porewater characteristics – were used to explain variations in arthropod community composition using a Canonical Correspondence Analysis. The results demonstrate that (1) paludiculture can increase arthropod richness on the landscape scale while (2) triggering a shift from xero- to hydrophilic taxa. Further, it was found that (3) in addition to water level other factors – such as the degree of peat degradation – are likely to drive species response. Based on the potential for increasing species richness on the landscape scale, it was concluded that paludiculture has potential for benefits beyond carbon sequestration.
Die antiken Thonlampen im Museum Wallraf-Richartz zu Köln
Creators: name: Kisa, Anton
Publisher: name: Bonner Jahrbücher
Year: 2018

description: [nicht vorhanden / not available]
description: Bonner Jahrbücher, Bd. 93 (1892): Jahrbücher des Vereins von Alterthumsfreunden im Rheinlande
Kleinere Mittheilungen aus dem Provinzial-Museum in Bonn
Creators: name: Klein, Josef
Publisher: name: Bonner Jahrbücher
Year: 2018

description: [nicht vorhanden / not available]
description: Bonner Jahrbücher, Bd. 93 (1892): Jahrbücher des Vereins von Alterthumsfreunden im Rheinlande
title: On cracking in thick GaN layers grown on sapphire substrates
Creators: name: Mynbaeva, M.G.
name: Sitnikova,  A.A.
name: Smirnov, A.N.
name: Mynbaev,  K.D.
name: Lipsanen, H.
name: Kremleva, A.V.
name: Bauman, D.A.
name:  Bougrov, V.E.
name: Romanov, A.E.
Publisher: name: Peter the Great St. Petersburg Polytechnic University
Year: 2020

description: Self-organization mechanisms promoting elimination of cracks in thick GaN layers
grown on sapphire substrates are considered on the basis of the experimental results on the
fabrication of the layers by Hydride Vapor-Phase Epitaxy on MOCVD-grown GaN/Al2O3
templates. The obtained data support the supposition on the closure of tensile stress-related
cracks via diffusion processes and demonstrate the strong contribution of bulk diffusion in
addition to surface diffusion discussed earlier.
keV Neutrino Model Building
Creators: name: Merle, Alexander
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We review the model building aspects for keV sterile neutrinos as Dark Matter candidates. After giving a brief discussion of some cosmological and astrophysical aspects, we first discuss the currently known neutrino data and observables. We then explain the purpose and goal of neutrino model building, and review some generic methods used. Afterwards certain aspects specific for keV neutrino model building are discussed, before reviewing the bulk of models in the literature. We try to keep the discussion on a pedagogical level, while nevertheless pointing out some finer details where necessary and useful. Ideally, this review should enable a grad student or an interested colleague from cosmology or astrophysics with some prior experience to start working on the field.
description: v3: content matches published version in International Journal of Modern Physics D (discussion generally extended, discussions on separate seesaw and on vacuum alignment added, Q_6 scheme added, acknowledgements changed to comply with the referee's requests); 100 pages, 8 figures
title: 'Living the Dream' Cosmopolitan Post-Austerity Portuguese Migrants in London and the Desire for a Good Life
Creators: name: Franks, Lisa Victoria
Publisher: name: University of Kent
Year: 2021

description: This thesis asks how highly educated Portuguese migrants in London experience and embody the desire to live a 'good life'. In answering this question, I also explore the effect this desire has on the way my research participants relate to others in the context of social and economic changes wrought by the 2008 financial crisis and the years leading up to it. Drawing on nearly three years of anthropological fieldwork in London and Portugal, the conceptual basis of my thesis rests on a differentiation outlined by my research participants between 'old' (working class) and 'new' (cosmopolitan) Portuguese migrants. I conceptualise this conflict as a contradiction in orientations, which I address via a tri-faceted theoretical framework that interweaves theories of cosmopolitanism, temporality and 'good life'. In defining cosmopolitanism as an emerging sense of global commonality, underscored by inherent conflict (Vertovec and Cohen 2002), my analysis asks how migrant cosmopolitan identities are lived and understood within the desire for freedom/a 'good life', and ongoing relationships with kin and wider social and laboral networks. The temporal aspect of my analysis is inspired by a Deleuzian understanding of desire as a human condition, which links the individual and the collective, through what Deleuze and Guatarri (2003) refer to as 'assemblages'-the meeting of bodies, things and ideas across time and space. By taking into account an emerging set of local and global conditions as a backdrop to the transformative potential of migration (conceived as an ongoing process of becoming), I ask how my research participants' experiences of the world are lived and felt in temporal and spatial terms. Building on the anthropology of Self and personhood in the context of crisis in Southern Europe, my research offers a unique contribution-focusing on a 'Southern' problem which is felt and transformed in the 'Northern' context in which it takes place. I confirm that the work presented in this thesis is my own, unless otherwise stated.
Positive Definite Solutions of the Nonlinear Matrix Equation $X+A^{\mathrm{H}}\bar{X}^{-1}A=I$
Creators: name: Zhou, Bin
name: Cai, Guang-Bin
name: Lam, James
Publisher: name: arXiv
Year: 2012
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: This paper is concerned with the positive definite solutions to the matrix equation $X+A^{\mathrm{H}}\bar{X}^{-1}A=I$ where $X$ is the unknown and $A$ is a given complex matrix. By introducing and studying a matrix operator on complex matrices, it is shown that the existence of positive definite solutions of this class of nonlinear matrix equations is equivalent to the existence of positive definite solutions of the nonlinear matrix equation $W+B^{\mathrm{T}}W^{-1}B=I$ which has been extensively studied in the literature, where $B$ is a real matrix and is uniquely determined by $A.$ It is also shown that if the considered nonlinear matrix equation has a positive definite solution, then it has the maximal and minimal solutions. Bounds of the positive definite solutions are also established in terms of matrix $A$. Finally some sufficient conditions and necessary conditions for the existence of positive definite solutions of the equations are also proposed.
Overgroups of regular unipotent elements in reductive groups
Creators: name: Bate, Michael
name: Martin, Ben
name: Roehrle, Gerhard
Publisher: name: arXiv
Year: 2021
Subjects: subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 20G15, 20G40, 20E45, 14L24

description: We study reductive subgroups $H$ of a reductive linear algebraic group $G$ -- possibly non-connected -- such that $H$ contains a regular unipotent element of $G$. We show that under suitable hypotheses, such subgroups are $G$-irreducible in the sense of Serre. This generalizes results of Malle, Testerman and Zalesski. We obtain analogous results for Lie algebras and for finite groups of Lie type. Our proofs are short, conceptual and uniform.
description: 13 pages; v2 added Corollary 5.2; v3 final version; some references added, further small changes; to appear in Forum of Mathematics, Sigma
Linear responses of D0-branes via gauge/gravity correspondence
Creators: name: Matsuo, Yoshinori
name: Sasai, Yuya
name: Sekino, Yasuhiro
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study linear responses of D0-branes in the low frequency region by using gauge/gravity correspondence. The dynamics of the D0-branes is described by Matrix theory with finite temperature, which is dual to a near extremal D0-brane black hole solution. We analyze the tensor mode and vector modes of a stress tensor and a Ramond-Ramond 1-form current of Matrix theory. Then, we show that if a cutoff surface is close to a horizon of the D0-brane black hole, the linear responses take forms similar to the hydrodynamic stress tensor and current on S^8. By taking a Rindler limit, those linear responses come to obey the hydrodynamics exactly, which is consistent with previous works on a Rindler fluid. We also show that if the cutoff surface is far from the horizon, the linear responses do not take the forms of the hydrodynamic stress tensor and current on S^8. Especially, we find that the vector modes no longer possess a diffusion pole in the low frequency region, which indicates that the linear responses of the D0-branes cannot be explained by hydrodynamics.
description: 40 pages, 1 figure; v2: references added and minor corrections; v3: minor corrections
Theory for the coalescence of viscous lenses
Creators: name: Tewes, Walter
name: Hack, Michiel A.
name: Datt, Charu
name: Peng, Gunnar G.
name: Snoeijer, Jacco H.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Drop coalescence occurs through the rapid growth of a liquid bridge that connects the two drops. At early times after contact, the bridge dynamics is typically self-similar, with details depending on the geometry and viscosity of the liquid. In this paper we analyse the coalescence of two-dimensional viscous drops that float on a quiescent deep pool; such drops are called liquid lenses. The analysis is based on the thin-sheet equations, which were recently shown to accurately capture experiments of liquid lens coalescence. It is found that the bridge dynamics follows a self-similar solution at leading order, but, depending on the large-scale boundary conditions on the drop, significant corrections may arise to this solution. This dynamics is studied in detail using numerical simulations and through matched asymptotics. We show that the liquid lens coalescence can involve a global translation of the drops, a feature that is confirmed experimentally.
title: Two scale homogenization in ternary locally resonant metamaterials
Creators: name: Comi, C.
name: Moscatelli,  M.
name: Marigo, J-J.
Publisher: name: Peter the Great St. Petersburg Polytechnic University
Year: 2020

description: In this work, we exploit the two-scale homogenization approach to compute
explicitly the band gaps for out-of-plane wave propagation in ternary locally resonant
metamaterials (LRM) with two-dimensional periodicity. The homogenization approach,
recently developed by the authors for binary LRM, leads to the definition of the dynamic
effective mass density, depending on the frequency, that becomes negative near the resonant
frequencies of the inclusions. The intervals of negative effective mass give the band gaps.
These explicit solutions put in evidence the dependence of the spectral gaps on the geometric
parameters of the unit cell and on the mechanical properties of the three constituent materials.
The range of frequency where the asymptotic homogenization approach is equivalent to the
Bloch-Floquet theory is also established and confirmed by numerical simulations.
Laura Chioffi, Gli elogia augustei del Foro Romano. Aspetti epigrafici e topografici
Creators: name: Vössing, Konrad
Publisher: name: Bonner Jahrbücher
Year: 2018

description: Rezension zu: Laura Chioffi, Gli elogia augustei del Foro Romano. Aspetti epigrafici e topografici. Opuscula Epigraphica, Band 7. Edizione Quasar, Rom 1996. 92 Seiten, 13 Tafeln.
description: Bonner Jahrbücher, Bd. 198.1998(2001): Bonner Jahrbücher
title: PROBING OF POLYCRYSTALLINE MAGNESIUM AT ULTRASONIC FREQUENCIES BY MECHANICAL SPECTROSCOPY
Creators: name: Kaminskii, V.V.
name: Lyubimova, Y.V.
name: Romanov, A.E.
Publisher: name: Peter the Great St. Petersburg Polytechnic University
Year: 2020

description: In the present work, using the method of a composite piezoelectric oscillator at a
frequency of 99-102 kHz, polycrystalline magnesium was studied under two types of
treatment: deformation and subsequent annealing. The influence of these types of treatments
on changes in the dislocation density and such an important structurally sensitive parameter as
the dynamic Young's modulus has been established. The values of micro-yield stress are
determined. With a longitudinal deformation of 1.7%, at the strain amplitude of 5×10-6 , its
value decreased from 2.9 MPa to 1.7 MPa; after annealing at 400 °C, it increased to 5.8 MPa.
Michael Wyss (Hrsg.) in Zusammenarbeit mit Nicole Meyer-Rodrigues, Atlas historique de Saint Denis. Des origines au XVIIIe siècle
Creators: name: Fehring, Günter P.
Publisher: name: Bonner Jahrbücher
Year: 2018

description: Rezension zu: Michael Wyss (Hrsg.) in Zusammenarbeit mit Nicole Meyer-Rodrigues, Atlas historique de Saint Denis. Des origines au XVIIIe siècle. Documents d’Archéologie Française, Band 59. Éditions de la Maison des Sciences de L’homme, Paris 1996. 445 Seiten, 384 Abbildungen.
description: Bonner Jahrbücher, Bd. 198.1998(2001): Bonner Jahrbücher
Magnetic Catalysis vs Magnetic Inhibition
Creators: name: Fukushima, Kenji
name: Hidaka, Yoshimasa
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss the fate of chiral symmetry in an extremely strong magnetic field B. We investigate not only quark fluctuations but also neutral meson effects. The former would enhance the chiral-symmetry breaking at finite B according to the Magnetic Catalysis, while the latter would suppress the chiral condensate once B exceeds the scale of the hadron structure. Using a chiral model we demonstrate how neutral mesons are subject to the dimensional reduction and the low dimensionality favors the chiral-symmetric phase. We point out that this effect, the Magnetic Inhibition, can be a feasible explanation for recent lattice-QCD data indicating the decreasing behavior of the chiral-restoration temperature with increasing B.
description: 5 pages, 2 figures
On the expressive power of non-deterministic and unambiguous Petri nets over infinite words
Creators: name: Finkel, Olivier
name: Skrzypczak, Michał
Publisher: name: arXiv
Year: 2021
Subjects: subject: Formal Languages and Automata Theory (cs.FL)
subject: FOS: Computer and information sciences

description: We prove that $ω$-languages of (non-deterministic) Petri nets and $ω$-languages of (non-deterministic) Turing machines have the same topological complexity: the Borel and Wadge hierarchies of the class of $ω$-languages of (non-deterministic) Petri nets are equal to the Borel and Wadge hierarchies of the class of $ω$-languages of (non-deterministic) Turing machines. We also show that it is highly undecidable to determine the topological complexity of a Petri net $ω$-language. Moreover, we infer from the proofs of the above results that the equivalence and the inclusion problems for $ω$-languages of Petri nets are $Π_2^1$-complete, hence also highly undecidable. Additionally, we show that the situation is quite the opposite when considering unambiguous Petri nets, which have the semantic property that at most one accepting run exists on every input. We provide a procedure of determinising them into deterministic Muller counter machines with counter copying. As a consequence, we entail that the $ω$-languages recognisable by unambiguous Petri nets are $Δ^0_3$ sets.
description: arXiv admin note: substantial text overlap with arXiv:1712.07945
title: A Numerical Acoustic Fluid-structure Simulation of Therapeutic Ultrasound Angioplasty
Creators: name: Gavin, Graham
name: Dolan, Finbar
name: Hashmi, M.S J
name: McGuinness, Garrett
Publisher: name: Technological University Dublin
Year: 2006

description: INTRODUCTION Therapeutic ultrasound angioplasty is the delivery of high amplitude ultrasonic displacements to the distal-tip of small diameter wire waveguides with the goal of disrupting atherosclerotic plaques. This is a minimally invasive procedure that may have potential' in the treatment of complicated chronic total occlusions. The disruption of plaque is due to direct contact ablation and also cavitation, pressure waves and acoustic streaming in the fluid surrounding the vibrating waveguide distal-tip [1]. Cavitation appears to play a major role and some authors have suggested that plaque ablation is only evident above the cavitation threshold [2]. Makin and Everbach [3] performed experimental measurements of the acoustic pressures in the field surrounding a vibrating wire waveguide distal-tip (frequency = 22.5 kHz, displacement amplitude = 651lm, tip diameter = 2.46mm). The measured acoustic pressures in the region ahead of the distal-tip are shown in Figure I. No measurements could be made in the region close to the tip but the authors concluded that these pressures would be sufficient to cause the cavitation that was observed, based on the trend in Figure I. This work describes a numerical acoustic fluidstructure model of the wire waveguide and fluid surrounding the distal-tip. The model will predict wire waveguide behaviour to a prescribed ultrasonic input displacement and will predict pressures developed around the distal-tip. METHODS An axisymmetric numerical model of the wire waveguide and fluid surrounding the distal-tip based on the device description by Makin and Everbach [3] was developed in ANSYS©. The model consisted of both structural elements (Plane42) for the waveguide and acoustic elements (Fluid29) for the fluid. A tluidstructure interface was placed at element couplings and infinite acoustic boundary elements (Fluid 129) defined the extremities of the model preventing acoustic reflection RESULTS A comparison of the experimental [3] and the numerical results are shown in Figure l. A close comparison is achieved and, in addition, the numerical model can predict pressures at the fluid-structure interface. With the inclusion of a cavitation threshold (CT), displacements and frequencies required to cause cavitation can be predicted. CONCLUSION The validated model can be used to investigate the effects of changing device parameters such as frequency of operation, displacement amplitudes and geometry, on both waveguide structural response (displacements and stresses) and pressures developed in the surrounding fluid.
Rook placements in $G_2$ and $F_4$ and associated coadjoint orbits
Creators: name: Ignatev, Mikhail V.
name: Surkov, Matvey A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: 17B08, 17B10, 17B22, 17B25, 17B30, 17B35

description: Let $\mathfrak{n}$ be a maximal nilpotent subalgebra of a simple complex Lie algebra with root system $Φ$. A subset $D$ of the set $Φ^+$ of positive roots is called a rook placement if it consists of roots with pairwise non-positive scalar products. To each rook placement $D$ and each map $ξ$ from $D$ to the set $\mathbb{C}^{\times}$ of nonzero complex numbers one can naturally assign the coadjoint orbit $Ω_{D,ξ}$ in the dual space $\mathfrak{n}^*$. By definition, $Ω_{D,ξ}$ is the orbit of $f_{D,ξ}$, where $f_{D,ξ}$ is the sum of root covectors $e_α^*$ multiplied by $ξ(α)$, $α\in D$. (In fact, almost all coadjoint orbits studied at the moment have such a form for certain $D$ and $ξ$.) It follows from the results of Andrè that if $ξ_1$ and $ξ_2$ are distinct maps from $D$ to $\mathbb{C}^{\times}$ then $Ω_{D,ξ_1}$ and $Ω_{D,ξ_2}$ do not coincide for classical root systems $Φ$. We prove that this is true if $Φ$ is of type $G_2$, or if $Φ$ is of type $F_4$ and $D$ is orthogonal.
description: 16 pages, 4 figures