cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Gravitational instability of solids assisted by gas drag: slowing by turbulent mass diffusivity
Creators: name: Shariff, Karim
name: Cuzzi, Jeffrey N.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The Goldreich and Ward (1973) (axisymmetric) gravitational instability of a razor thin particle layer occurs when the Toomre parameter $Q_T \equiv c_p Ω_0 / πG Σ_p < 1$ ($c_p$ being the particle dispersion velocity). Ward(1976,2000) extended this analysis by adding the effect of gas drag upon particles and found that even when $Q_T > 1$, sufficiently long waves were always unstable. Youdin (2005a,b) carried out a detailed analysis and showed that the instability allows chondrule-sized ($\sim 1 $ mm) particles to undergo radial clumping with reasonable growth times even in the presence of a moderate amount of turbulent stirring. The analysis of Youdin includes the role of turbulence in setting the thickness of the dust layer and in creating a turbulent particle pressure in the momentum equation. However, he ignores the effect of turbulent mass diffusivity on the disturbance wave. Here we show that including this effect reduces the growth-rate significantly, by an amount that depends on the level of turbulence, and reduces the maximum intensity of turbulence the instability can withstand by 1 to 3 orders of magnitude. The instability is viable only when turbulence is extremely weak and the solid to gas surface density of the particle layer is considerably enhanced over minimum-mass-nebula values. A simple mechanistic explanation of the instability shows how the azimuthal component of drag promotes instability while the radial component hinders it. A gravito-diffusive overstability is also possible but never realized in the nebula models.
description: Accepted, June 14, 2011, Astrophysical Journal
Every weakly initially m-compact topological space is mpcap
Creators: name: Lipparini, Paolo
Publisher: name: arXiv
Year: 2010
Subjects: subject: General Topology (math.GN)
subject: FOS: Mathematics
subject: 54D20, 54A20

description: The statement in the title solves a problem raised by T. Retta. We also present a variation of the result in terms of $[ μ,κ]$-compactness.
description: 4 pages
FLAME Deliverable 24 - Mitigating Extreme Wildfires Video (D5.4)
Creators: name: Giannaros, Theodore
name: Papavasileiou, Georgios
Publisher: name: National Observatory of Athens
Year: 2023

description: A short video discussing tools for mitigating extreme wildfires. Greek audio with English subtitles. The video is also available on YouTube at https://www.youtube.com/watch?v=_s36YvSjfMo.
Planar Yang-Mills 101.pdf
Creators: name: R. Wright, Nicholas
Publisher: name: figshare
Year: 2019
Subjects: subject: 20299 Atomic, Molecular, Nuclear, Particle and Plasma Physics not elsewhere classified
subject: FOS: Physical sciences
subject: 20399 Classical Physics not elsewhere classified
subject: 20499 Condensed Matter Physics not elsewhere classified
subject: 20601 Degenerate Quantum Gases and Atom Optics
subject: 20602 Field Theory and String Theory
subject: General Relativity
subject: M-Theory
subject: 20202 Nuclear Physics
subject: 20203 Particle Physics
subject: 20204 Plasma Physics; Fusion Plasmas; Electrical Discharges
subject: 20603 Quantum Information, Computation and Communication
subject: Quantum Mechanics
subject: 20699 Quantum Physics not elsewhere classified
subject: Special Relativity

description: The point is to define the limiting continuum field theory. In principle, this might even be done without taking limits. The Hamiltonian, the operator on the quantum Hilbert space which generates time translations, has a square root called the supercharge. Here we use the Moon model and Parfait logic. Furthermore, although one has changed the problem, one still has a fairly close relation to the original problem using the ideology of the renormalization group. We can start with a supersymmetric theory, and add supersymmetry breaking terms to the action which only become important at long distances as many lattice spacings, to obtain a theory with the better renormalization properties of the supersymmetric theory at short distances, but which reduces to conventional Yang-Mills theory at longer distances. Thus, a solution to the problem in a sufficiently general class of supersymmetric theories, would in fact imply the solution of the original problem. We propose a Cacace tetraoxygen universe relative to a Poincaré Dodecahedral Space. This is called an oxozone.
Self force on a scalar charge in Kerr spacetime: eccentric equatorial orbits
Creators: name: Warburton, Niels
name: Barack, Leor
Publisher: name: arXiv
Year: 2011
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We present a numerical code for calculating the self force on a scalar charge moving in a bound (eccentric) geodesic in the equatorial plane of a Kerr black hole. We work in the frequency domain and make use of the method of extended homogeneous solutions [Phys.\ Rev.\ D {\bf 78}, 084021 (2008)], in conjunction with mode-sum regularization. Our work is part of a program to develop a computational architecture for fast and efficient self-force calculations, alternative to time-domain methods. We find that our frequency-domain method outperforms existing time-domain schemes for small eccentricities, and, remarkably, remains competitive up to eccentricities as high as $\sim 0.7$. As an application of our code we (i) compute the conservative scalar-field self-force correction to the innermost stable circular equatorial orbit, as a function of the Kerr spin parameter; and (ii) calculate the variation in the rest mass of the scalar particle along the orbit, caused by the component of the self force tangent to the four-velocity.
description: 26 pages, 9 figures. Minor typo corrected
Towards a model which merges soft and hard high-energy pp interactions
Creators: name: Martin, A. D.
name: Ryskin, M. G.
name: Khoze, V. A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We seek a model which describes both the high-energy soft $pp$ data and has the perturbative QCD attributes expected in the low x, relatively low Q^2 domain. We describe the present status of this endeavour.
description: 5 pages, Talk presented by A.D. Martin at the Int. Workshop on Diffraction in High Energy Physics (Diffraction 2010), Otranto (Lecce), Italy, 10-15 Sept. 2010
Efficient quantum transport simulation for bulk graphene heterojunctions
Creators: name: Liu, Ming-Hao
name: Richter, Klaus
Publisher: name: Universität Regensburg
Year: 2012
Subjects: subject: 530 Physik
subject: 72.80.Vp
subject: 72.10.Bg
subject: 73.23.Ad
subject: 73.40.Gk

description: The quantum transport formalism based on tight-binding models is known to be powerful in dealing with a wide range of open physical systems subject to external driving forces but is, at the same time, limited by the memory requirement's increasing with the number of atomic sites in the scattering region. Here we demonstrate how to achieve an accurate simulation of quantum transport feasible for experimentally sized bulk graphene heterojunctions at a strongly reduced computational cost. Without free tuning parameters, we show excellent agreement with a recent experiment on Klein backscattering [A. F. Young and P. Kim, Nature Phys. 5, 222 (2009)].
On a Class of Martingale Problems on Banach Spaces
Creators: name: Kunze, Markus C.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60H15, 60J25

description: We introduce the local martingale problem associated to semilinear stochastic evolution equations driven by a cylindrical Wiener process and establish a one-to-one correspondence between solutions of the martingale problem and (analytically) weak solutions of the stochastic equation. We also prove that the solutions of well-posed equations are strong Markov processes. We apply our results to semilinear stochastic equations with additive noise where the semilinear term is merely measurable and to stochastic reaction-diffusion equations with Hölder continuous multiplicative noise.
description: Incorporated referee's comments; final version
Classification of puck possession events in ice hockey
Creators: name: Tora, Moumita Roy
Publisher: name: University of British Columbia
Year: 2017

description: Group activity recognition in sports is often challenging due to the complex dynamics and interaction among the players. In this thesis, we propose a deep architecture to classify puck possession events in ice hockey. Our model consists of three distinct phases: feature extraction, feature aggregation and, learning and inference. For the feature extraction and aggregation, we use a Convolutional Neural Network (CNN) followed by a late fusion model on top to extract and aggregate different types of features that includes handcrafted homography features for encoding the camera information. The output from the CNN is then passed into a Recurrent Neural Network (RNN) for the temporal extension and classification of the events. The proposed model captures the context information from the frame features as well as the homography features. The individual attributes of the players and the interaction among them is also incorporated using a pre-trained model and team pooling. Our model requires only the player positions on the image and the homography matrix and does not need any explicit annotations for the individual actions or player trajectories, greatly simplifying the input of the system. We evaluate our model on a new Ice Hockey Dataset and a Volleyball Dataset. Experimental results show that our model produces promising results on both these challenging datasets with much simpler inputs compared with the previous work.
Ευγένιος Τριβιζάς: Παραμύθια από τη χώρα των χαμένων χαρταετών
Creators: name: Γ. Παπαντωνάκης
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2007

description: Ευγένιος Τριβιζάς: Παραμύθια από τη χώρα των χαμένων χαρταετών
description: ΚΕΙΜΕΝΑ, Issue 6 (September 2007)
title: Maternal Empowerment, Childcare Practices, And Child Nutrition In Rural Nepal: Examining The Pathways
Creators: name: Cunningham, K
Publisher: name: London School of Hygiene & Tropical Medicine
Year: 2014

description: Tackling persistent child undernutrition in South Asia will require a deeper understanding of structural determinants, including maternal resources and childcare practices. This study aimed to: (1) synthesise the evidence linking women’s empowerment and child nutritional status in South Asia; (2) investigate associations of women’s empowerment in agriculture and child nutrition in rural Nepal; (3) determine whether these associations differ by dimension of empowerment or nutritional indicator; and (4) explore whether child feeding and WASH facilities and practices mediate these associations.
Our review of prior empirical studies on women’s empowerment and child anthropometry in South Asia showed a general association, but heterogeneous and inconsistent findings. Thus, additional research and harmonisation of how women’s empowerment is defined and measured are needed.
Using a cross-sectional dataset, we constructed the Women’s Empowerment in Agriculture Index’s (WEAI) 5 Domains of Empowerment (5DE) sub-index to investigate the association between maternal empowerment and child LAZ, WAZ, and WLZ in rural Nepal. The aggregate 5DE was positively associated with LAZ and WAZ. Three component indicators had positive associations: leisure time satisfaction (LAZ), production autonomy (LAZ), and access to credit (LAZ/WAZ). We then used causal mediation techniques to test whether two childcare practices - feeding and WASH practices - mediated these associations. Both feeding and WASH facilities and practices were independtly positively associated with child LAZ; neither feeding nor WASH facilities and practices mediated the credit or production autonomy pathways but an indirect pathway from maternal satisfaction with leisure time to child LAZ was found for WASH facilities and practices.
This is the first South Asian study to investigate multiple domains of empowerment and assess pathways from care resources via childcare practices to child nutrition. Findings suggest that particular dimensions of empowerment may influence child nutrition more than others in particular contexts. Addressing child undernutrition in Nepal requires interventions to promote optimal feeding and WASH behaviours but also to address women’s disempowerment.
Renormalization fixed point of the KPZ universality class
Creators: name: Corwin, Ivan
name: Quastel, Jeremy
name: Remenik, Daniel
Publisher: name: arXiv
Year: 2011
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The one dimensional Kardar-Parisi-Zhang universality class is believed to describe many types of evolving interfaces which have the same characteristic scaling exponents. These exponents lead to a natural renormalization/rescaling on the space of such evolving interfaces. We introduce and describe the renormalization fixed point of the Kardar-Parisi-Zhang universality class in terms of a random nonlinear semigroup with stationary independent increments, and via a variational formula. Furthermore, we compute a plausible formula the exact transition probabilities using replica Bethe ansatz. The semigroup is constructed from the Airy sheet, a four parameter space-time field which is the Airy2 process in each of its two spatial coordinates. Minimizing paths through this field describe the renormalization group fixed point of directed polymers in a random potential. At present, the results we provide do not have mathematically rigorous proofs, and they should at most be considered proposals.
description: 19 pages, 2 figures; updated and expanded version with addition author (Remenik)
Acetylene-ammonia-18-crown-6 (1/2/1)
Creators: name: Grassl, Tobias
name: Hamberger, Markus
name: Korber, Nikolaus
Publisher: name: Universität Regensburg
Year: 2012
Subjects: subject: 540 Chemie

description: The title compound, C2H2·C12H24O6·2NH3, was formed by co-crystallization of 18-crown-6 and acetylene in liquid ammonia. The 18-crown-6 molecule has threefold rotoinversion symmetry. The acteylene molecule lies on the threefold axis and the whole molecule is generated by an inversion center. The two ammonia molecules are also located on the threefold axis and are related by inversion symmetry. In the crystal, the ammonia molecules are located below and above the crown ether plane and are connected by intermolecular N-H...O hydrogen bonds. The acetylene molecules are additionally linked by weak C-H...N interactions into chains that propagate in the direction of the crystallographic c axis. The 18-crown-6 molecule [occupancy ratio 0.830 (4):0.170 (4)] is disordered and was refined using a split model.
Το σύγχρονο παραμύθι του Ευγ. Τριβιζά: Μυθοπλασία και λόγος
Creators: name: Α. Ακριτόπουλος
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2007

description: Το σύγχρονο παραμύθι του Ευγ. Τριβιζά: Μυθοπλασία και λόγος
description: ΚΕΙΜΕΝΑ, Issue 6 (September 2007)
Από την «κινέζα κούκλα» στα «88 ντολμαδάκια» και τα «33 ρουμπίνια»: η λογική των υπερκειμένων στον παράλογο κόσμο των παραμυθιακών κειμένων
Creators: name: Α. Γιαννικοπούλου
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2007

description: Από την «κινέζα κούκλα» στα «88 ντολμαδάκια» και τα «33 ρουμπίνια»: η λογική των υπερκειμένων στον παράλογο κόσμο των παραμυθιακών κειμένων
description: ΚΕΙΜΕΝΑ, Issue 6 (September 2007)
Optomechanical sideband cooling of a micromechanical oscillator close to the quantum ground state
Creators: name: Riviere, Remi
name: Deleglise, Samuel
name: Weis, Stefan
name: Gavartin, Emanuel
name: Arcizet, Olivier
name: Schliesser, Albert
name: Kippenberg, Tobias J.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Cooling a mesoscopic mechanical oscillator to its quantum ground state is elementary for the preparation and control of low entropy quantum states of large scale objects. Here, we pre-cool a 70-MHz micromechanical silica oscillator to an occupancy below 200 quanta by thermalizing it with a 600-mK cold 3He gas. Two-level system induced damping via structural defect states is shown to be strongly reduced, and simultaneously serves as novel thermometry method to independently quantify excess heating due to the cooling laser. We demonstrate that dynamical backaction sideband cooling can reduce the average occupancy to 9+-1 quanta, implying that the mechanical oscillator can be found (10+- 1)% of the time in its quantum ground state.
description: 11 pages, 5 figures
A generalized Kac-Moody algebra of rank 14
Creators: name: Hoehn, Gerald
name: Scheithauer, Nils R.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics

description: We construct a vertex algebra of central charge 26 from a lattice orbifold vertex operator algebra of central charge 12. The BRST-cohomology group of this vertex algebra is a new generalized Kac-Moody algebra of rank 14. We determine its root space multiplicities and a set of simple roots.
description: LaTeX, 18 pages, 3 Tables. Published version. Revision contains some more details
Η «μεταμυθοπλασία» ως ερμηνευτικό εργαλείο στο έργο του S. Rushdie «Ο Χαρούν και η Θάλασσα των Ιστοριών»
Creators: name: Βασιλική Βασιλούδη
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2007

description: Η «μεταμυθοπλασία» ως ερμηνευτικό εργαλείο στο έργο του S. Rushdie «Ο Χαρούν και η Θάλασσα των Ιστοριών»
description: ΚΕΙΜΕΝΑ, Issue 5 (January 2007)
Biological consequences of rapid environmental change in the American pika Ochotona princeps
Creators: name: Waterhouse, Matthew David
Publisher: name: University of British Columbia
Year: 2017

description: Species are often confronted with rapid environmental change that require an adaptive response to maintain viability. The source of this environmental change can be natural, but is frequently anthropogenic in nature. In this thesis, I document the biological consequences of rapid environmental change in a sensitive mammal, the American pika (Ochotona princeps). In Chapter 2, I used microsatellite genetic makers to investigate the consequences of landscape modifications for pika populations relative to two major developments in British Columbia, Canada: a large open-pit copper mine (Highland Valley Copper) under partial reclamation and a bisecting major highway (97C). I found evidence for restricted movement associated with human-modified landscapes and showed evidence for fragmentation potentially resulting from the highway. Rapid environmental change often elicits a stress response in animals involving elevated glucocorticoids. In Chapter 3, I applied a novel technique to measure chronic stress in pikas by measuring extracted corticosterone from hair samples. Applying this method along two elevational transects of populations in North Cascades National Park, WA, allowed me to assess individual factors influencing stress in the American pika. My results showed elevated stress levels associated with smaller body sizes, female pikas, and with low early-spring ambient temperatures. This study provided direct physiological evidence for thermal stress in a climate-sensitive mammal and provides a useful tool for assessing climate stress in the American pika. Selective pressure from such thermal stress can result in local adaptation via natural selection. In Chapter 4, I used genotyping-by-sequencing to assess genotype-environment associations along these same elevational transects. The results showed a consistent genomic response to climate conditions across both transects and provide preliminary evidence for cold stress and hypoxia in the American pika. Additionally, I resolved consistent evidence for a downslope bias in gene flow, which may interfere with the upslope movement of individuals that is predicted with ongoing climate change. Taken together, these chapters show consistent patterns of restricted gene flow and thermal stress in the American pika and show the potential that climate-mediated natural selection is resulting in the development of local climate adaptations.
Έμμετρες επιβιώσεις της αισωπικής παράδοσης κατά την περίοδο του ρομαντισμού : παιδαγωγική και αισθητική προσέγγιση
Creators: name: Χρήστος Γεωργίου
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2007

description: Έμμετρες επιβιώσεις της αισωπικής παράδοσης κατά την περίοδο του ρομαντισμού : παιδαγωγική και αισθητική προσέγγιση
description: ΚΕΙΜΕΝΑ, Issue 5 (January 2007)
The energy functional on the Virasoro-Bott group with the $L^2$-metric has no local minima
Creators: name: Bruveris, Martins
Publisher: name: arXiv
Year: 2011
Subjects: subject: Differential Geometry (math.DG)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35Q53, 35A15, 58B20, 58D05, 58D15, 58E12

description: The geodesic equation for the right invariant $L^2$-metric (which is a weak Riemannian metric) on each Virasoro-Bott group is equivalent to the KdV-equation. We prove that the corresponding energy functional, when restricted to paths with fixed endpoints, has no local minima. In particular solutions of KdV don't define locally length-minimizing paths.
description: 12 pages, revised version
Οι μύθοι του Λαφονταίν: Ανάμεσα στην παράδοση και τη νεωτερικότητα
Creators: name: Lebrun, Marlène
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2007

description: Οι μύθοι του Λαφονταίν: Ανάμεσα στην παράδοση και τη νεωτερικότητα
description: ΚΕΙΜΕΝΑ, Issue 5 (January 2007)
The Lateral Occipital Cortex in the Face Perception Network: An Effective Connectivity Study
Creators: name: Nagy, Krisztina
name: Greenlee, Mark W.
name: Kovács, Gyula
Publisher: name: Universität Regensburg
Year: 2012
Subjects: subject: dynamic causal modeling, face perception, effective connectivity, fusiform face area, lateral occipital cortex, occipital face area
subject: 150 Psychologie

description: The perception of faces involves a large network of cortical areas of the human brain. While several studies tested this network recently, its relationship to the lateral occipital (LO) cortex known to be involved in visual object perception remains largely unknown. We used functional magnetic resonance imaging and dynamic causal modeling (DCM) to test the effective connectivity among the major areas of the face-processing core network and LO. Specifically, we tested how LO is connected to the fusiform face area (FFA) and occipital face area (OFA) and which area provides the major face/object input to the network. We found that LO is connected via significant bidirectional connections to both OFA and FFA, suggesting the existence of a triangular network. In addition, our results also suggest that face- and object-related stimulus inputs are not entirely segregated at these lower level stages of face-processing and enter the network via the LO. These results support the role of LO in face perception, at least at the level of face/non-face stimulus discrimination.
A critical revision of the churchill snoutfish, genus Petrocephalus Marcusen, 1854 (Actinopterygii: Teleostei: Mormyridae), from southern and eastern Africa, with the recognition of Petrocephalus tanensis, and the description of five new species
Creators: name: Kramer, Bernd
name: Bills, Roger
name: Skelton, Paul
name: Wink, Michael
Publisher: name: Universität Regensburg
Year: 2012
Subjects: subject: systematics; morphometrics; electric organ discharges; molecular genetics; allopatric speciation
subject: 570 Biowissenschaften, Biologie
subject: 590 Tiere (Zoologie)

description: We morphologically and genetically studied the southern African electric fish Petrocephalus catostoma, or churchill, and its six nominal species, five of which by synonymization (three valid subspecies). We reinstate the synonymized species, and recognize Petrocephalus tanensis (Whitehead and Greenwood, 1959) from the Tana River in Kenya, also using electric organ discharges. The Okavango delta (Botswana) is inhabited by Petrocephalus okavangensis sp. nov. and Petrocephalus magnitrunci sp. nov., and the Namibian Cunene River by Petrocephalus magnoculis sp. nov. We recognize Petrocephalus petersi sp. nov. for the Lower Zambezi River (Mozambique), and Petrocephalus longicapitis sp. nov. for the Upper Zambezi River (Namibia). The Lufubu River in Northern Zambia is inhabited by Petrocephalus longianalis sp. nov. For the southern churchill, Petrocephalus wesselsi Kramer and Van der Bank, 2000, we confirm intraspecific and interspecific differentiation. Sequence data from mitochondrial DNA confirm differentiation of two new western and two eastern species, forming mutual sister groups.
Η Αντιστροφή στην Φορά της Δημιουργίας (από τον αρχαιοελληνικό μύθο στο σύγχρονο λαϊκό παραμύθι)
Creators: name: Γιάννης Παπαδόπουλος
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2006

description: Η Αντιστροφή στην Φορά της Δημιουργίας (από τον αρχαιοελληνικό μύθο στο σύγχρονο λαϊκό παραμύθι)
description: ΚΕΙΜΕΝΑ, Issue 4 (July 2006)
Magnetic Nanobeads as Support for Zinc(II)–Cyclen Complexes: Selective and Reversible Extraction of Riboflavin
Creators: name: Kainz, Quirin M.
name: Späth, Andreas
name: Weiss, Stefan
name: Michl, Thomas D.
name: Schätz, Alexander
name: Stark, Wendelin J.
name: König, Burkhard
name: Reiser, Oliver
Publisher: name: Universität Regensburg
Year: 2012
Subjects: subject: chelates; fluorescence spectroscopy; molecular recognition; nanoparticles; polymerization
subject: 540 Chemie

description: Fishing for riboflavin: Highly magnetic polymer-coated Fe/C nanoparticles are used as supports for zinc(II)–cyclen complexes. Quantitative and reversible extraction of riboflavin (vitamin B2) from aqueous solutions and a vitamin dietary supplement is achieved retaining high efficacy for six consecutive cycles. Applying an external magnetic field readily recycles the nanobeads.
Electron transport in waveguides with spatially modulated strengths of the Rashba and Dresselhaus terms of the spin-orbit interaction
Creators: name: Krstajic, P. M.
name: Rezasoltani, E.
name: Vasilopoulos, P.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We study electron transport through waveguides (WGs) in which the strengths of the Rashba ($α$) and Dresselhaus ($β$) terms of the spin-orbit interaction (SOI) vary in space. Subband mixing, due to lateral confinement, is taken into account only between the two first subbands. For sufficiently narrow WGs the transmission $T$ exhibits a square-like shape as a function of $α$ or $β$. Particular attention is paid to the case of equal SOI strengths, $α=β$, for which spin-flip processes are expected to decrease. The transmission exhibits resonances as a function of the length of a SOI-free region separating two regions with SOI present, that are most pronounced for $α=β$. The sign of $α$ strongly affects the spin-up and spin-down transmissions. The results show that the main effect of subband mixing is to shift the transmission resonances and to decrease the transmission from one spin state to another. The effect of possible band offsets between regions that have different SOI strengths and effective masses is also discussed.
Οι διασκευές αριστοφανικών κωμωδιών για παιδιά: το παράδειγμα της Eιρήνης, από τη Σ. Ζαραμπούκα
Creators: name: Ελένη Καλκάνη
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2006

description: Οι διασκευές αριστοφανικών κωμωδιών για παιδιά: το παράδειγμα της Eιρήνης, από τη Σ. Ζαραμπούκα
description: ΚΕΙΜΕΝΑ, Issue 4 (July 2006)
A program of research addressing exposure assessment in epidemiological studies of shift work
Creators: name: Hall, Amy
Publisher: name: University of British Columbia
Year: 2017

description: BACKGROUND Shift work is common with wide-ranging implications for worker health. It is also complex, presenting challenges for exposure assessment in epidemiological studies and the development of strong evidence to inform health interventions and policies. This dissertation generated new information on the measurement, assignment, and determinants of shift work exposure, in order to address important limitations in this field of epidemiology. METHODS In Chapter 2, 152 full-shift personal light-at-night measurements were collected from 102 shift workers in emergency services and healthcare to investigate exposure variability and different exposure metrics. In Chapter 3, multiple exposure indicators were constructed for a national survey of nurses (n=11,450) to demonstrate the impacts of exposure assignment on observed relationships between shift work and depression. In Chapter 4, interviews were conducted with 88 employers in one Canadian province to examine determinants of workplace-level shift work policies and practices. RESULTS In Chapter 2, average light-at-night exposures varied across occupations and settings; between-group variance exceeded between-worker and within-worker variance, and all exposure metrics were moderately-to-highly correlated. In Chapter 3, the strongest relationships between shift work and depression were observed in the model with highest exposure precision, defined by shift timing and rotation intensity, whereas weak relationships were observed in models with lower exposure precision, defined by shift timing or presence/absence of shift work. In Chapter 4, long duration shifts varied by industry and were more likely in large workplaces; shift work education/training was more likely in large workplaces and those without seasonal shift work; and nighttime lighting policies were more likely in workplaces reporting that maintenance, client service needs, or prior nighttime incidents affected shift work. CONCLUSIONS This dissertation can inform future epidemiological studies of shift work. Chapter 2 identified high-level exposure indicators (e.g., occupation groupings) and flexibility in the choice of highly correlated metrics for light-at-night exposure studies. Chapter 3 showed that increasing the precision of exposure assignment reduced measurement error and effect attenuation for the outcome of depression. Chapter 4 identified determinants of workplace-level shift work policies and practices (e.g., industry, employer size, temporary work, and employer motivations) to consider in future research and interventions.
Digital security issues for critical infrastructures – Focus on the Electricity Sector
Creators: name: GUYOMARD, Frédéric
name: ROMANO, Luigi
name: GKOTSIS, Ilias
Publisher: name: Zenodo
Year: 2024

description: EU-CIP has released a white paper on the protection of the critical infrastructures of the energy sector. The whitepaper reviews the main challenges and threats faced by energy sector with a special focus on the Electricity Sector. Moreover, it proposes solutions that can effectively address these challenges supporting  operators and other stakeholders to increase the resilience of their critical infrastructures.
Galois theory of difference equations with periodic parameters
Creators: name: Antieau, Benjamin
name: Ovchinnikov, Alexey
name: Trushin, Dmitry
Publisher: name: arXiv
Year: 2010
Subjects: subject: Commutative Algebra (math.AC)
subject: Quantum Algebra (math.QA)
subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics
subject: 12H10, 13N99, 20H25, 39A13

description: We develop a Galois theory for systems of linear difference equations with periodic parameters, for which we also introduce linear difference algebraic groups. We then apply this to constructively test if solutions of linear q-difference equations, with complex q, not a root of unity, satisfy any polynomial q'-difference equations with q' being a root of unity.
description: 42 pages
Μορφές της αρχαίας ελληνικής μυθολογίας σε βυζαντινά εικονογραφημένα χειρόγραφα
Creators: name: Αλεξάνδρα Στεφανίδου
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2006

description: Μορφές της αρχαίας ελληνικής μυθολογίας σε βυζαντινά εικονογραφημένα χειρόγραφα
description: ΚΕΙΜΕΝΑ, Issue 4 (July 2006)
Magnetic properties of HgTe quantum wells
Creators: name: Scharf, Benedikt
name: Matos-Abiague, Alex
name: Fabian, Jaroslav
Publisher: name: Universität Regensburg
Year: 2012
Subjects: subject: 530 Physik

description: Using analytical formulas as well as a finite-difference scheme, we investigate the magnetic field dependence of the energy spectra and magnetic edge states of HgTe/CdTe-based quantum wells in the presence of perpendicular magnetic fields and hard walls for the band-structure parameters corresponding to the normal and inverted regimes. Whereas one can not find counterpropagating, spin-polarized states in the normal regime, below the crossover point between the uppermost (electronlike) valence and lowest (holelike) conduction Landau levels, one can still observe such states at finite magnetic fields in the inverted regime, although these states are no longer protected by time-reversal symmetry. Furthermore, the bulk magnetization and susceptibility in HgTe quantum wells are studied, in particular their dependence on the magnetic field, chemical potential, and carrier densities. We find that for fixed chemical potentials as well as for fixed carrier densities, the magnetization and magnetic susceptibility in both the normal and the inverted regimes exhibit de Haas–van Alphen oscillations, the amplitude of which decreases with increasing temperature. Moreover, if the band structure is inverted, the ground-state magnetization (and consequently also the ground-state susceptibility) is discontinuous at the crossover point between the uppermost valence and lowest conduction Landau levels. At finite temperatures and/or doping, this discontinuity is canceled by the contribution from the electrons and holes and the total magnetization and susceptibility are continuous. In the normal regime, this discontinuity of the ground-state magnetization does not arise and the magnetization is continuous for zero as well as finite temperatures.
Φίλιππου Μανδηλαρά, Ο Ολυμπιονίκης που έβλεπε τα ψάρια να περνούν: μια ιστορία της ελληνικής αρχαιότητας στην επικαιρότητα των Ολυμπιακών Αγώνων
Creators: name: Ελπινίκη Νικολουδάκη-Σουρή
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2006

description: Φίλιππου Μανδηλαρά, Ο Ολυμπιονίκης που έβλεπε τα ψάρια να περνούν: μια ιστορία της ελληνικής αρχαιότητας στην επικαιρότητα των Ολυμπιακών Αγώνων
description: ΚΕΙΜΕΝΑ, Issue 4 (July 2006)
КАТАМЕНИАЛЬНЫЙ ПНЕВМОТОРАКС: ВОПРОСЫ ПАТОМОРФОЛОГИИ И ХИРУРГИЧЕСКОГО ЛЕЧЕНИЯ
Creators: name: Юлчиев, Каримжон
name: Хайдаров, Абдулхамид
Publisher: name: Zenodo
Year: 2024

description: Проблема торакального эндометриоза (ТЭи ка тамениального пневмоторакса лежит в зоне ответственности как па томорфологов, так и клиницистов – торакальных хирургов, акушеров-гинекологов. Эндометриоз характеризуется наличием эн дометридоподобных желез и стромы внеполости матки и поражает 6-10% женщин репродуктивного возраста. Наиболее распространенным очагом заболевания за пределами брюшной полости и таза является грудная полость. Эндометриоз в легочной паренхиме или на поверхностях диафрагмы и плевры вызывает целый ряд клинических и рентгенологических проявлений: катамениальный пневмоторакс, гемоторакс, кровохарканье, легочные узелки, в результате чего формируется так называемый синдром ТЭ.
H «παραμόρφωση» του Αχιλλέα: Ξαναδιαβάζοντας διασκευές της Ιλιάδας για παιδιά
Creators: name: Ιωάννα Καλιακάτσου
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2006

description: H «παραμόρφωση» του Αχιλλέα: Ξαναδιαβάζοντας διασκευές της Ιλιάδας για παιδιά
description: ΚΕΙΜΕΝΑ, Issue 4 (July 2006)
Fixed Points for Mappings with a Contractive Iterate at Each Point
Creators: name: Karaibryamov, Samet
name: Zlatanov, Boyan
Publisher: name: arXiv
Year: 2011
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 47H10, 47H09

description: We generalize the results of Sehgal and Guseman for mappings on a complete metric space with a contractive iterate condition at each point.
description: 12 pages, 2 figures
A halo blue straggler on a highly eccentric retrograde orbit
Creators: name: Tillich, A.
name: Przybilla, N.
name: Scholz, R. -D.
name: Heber, U.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Blue straggler, which are stars that appear to be younger than they should be, are an important population of unusual stars in both stellar clusters and the halo field of the Galaxy. Most formation scenarios evoke either stellar collisions or binary stars that transfer mass or merge. We investigate high-velocity stars in the Galactic halo and perform a spectral and kinematical analysis to shed light on their nature and origin. Here we report that SDSSJ130005.62+042201.6 (J1300+0422 for short) is an A-type star of unusually large radial velocity (504.6 $\pm$ 5 \kms). From a quantitative NLTE (and LTE) spectral analysis of medium-resolution optical spectra, the elemental composition is derived. Proper motion measurements combined with a spectroscopic distance estimate allow us to determine its present space velocity. Its kinematical properties are derived by integrating the equation of motion in the Galactic potential. We find J1300+0422 to be metal poor ([M/H]=$-1.2$) and exhibit an $α$-element enrichment ($0.3-0.4$~dex) that is characteristic of the halo population, as confirmed by a kinematical analysis of its 3D space motions, which places it on a highly eccentric retrograde Galactic orbit. The mass of J1300+0422 (1.15 $\pm$ 0.10 M$_\odot$) is higher than the globular cluster turn-off masses indicating that it is a halo blue straggler star. At a Galactic rest-frame velocity of $\approx$467~\kms, the star travels faster than any known blue straggler but is still bound to the Galaxy.
description: 6 pages, 7 figures, accepted for publication in A&A
Forschungsdatenmanagement: Umgang mit Forschungsdaten.
Creators: name: Strauch-Davey, Annette
Publisher: name: Zenodo
Year: 2021
Subjects: RDM
Open Science FDM UB Hildesheim

description: Offene Wissenschaft sei in Zeiten des globalen, digitalen Wandels eine wichtige Gewährleistung der verfassungsmäßig garantierten Freiheit der Wissenschaft, so Annette Strauch-Davey. Sie funktioniert immer dann, wenn Strategien und Verfahren gebündelt werden, sodass alle Bestandteile des wissenschaftlichen Prozesses offen zugänglich, nachvollziehbar und nachnutzbar gemacht werden.
FLAME Deliverable 25 - Policy Brief (D5.5)
Creators: name: Giannaros, Theodore
name: Papavasileiou, Georgios
Publisher: name: National Observatory of Athens
Year: 2024

description: This policy brief, derived from the outcomes of the FLAME research project, outlines the importance of fire weather in wildfire management and current challenges related to climate change, while providing recommendations for integra9ng fire weather into everyday wildfire management activities in Greece.
The role of affect and reward in the conflict-triggered adjustment of cognitive control
Creators: name: Dreisbach, Gesine
name: Fischer, Rico
Publisher: name: Universität Regensburg
Year: 2012
Subjects: subject: cognitive control, conflict adaptation, affect, reward, conflict monitoring
subject: 150 Psychologie

description: Adapting to changing task demands is one of the hallmarks of human cognition. According to an influential theory, the conflict monitoring theory, the adaptation of information processing occurs in a context-sensitive manner in that conflicts signal the need for control recruitment. Starting from the conflict monitoring theory, here the authors discuss the role of affect in the context of conflict-triggered processing adjustments from three different perspectives: (1) the affective value of conflict per se, (2) the affective modulation of conflict-triggered processing adjustments, and (3) the modulation of conflict adaptation by reward. Based on the current empirical evidence, the authors stress the importance of disentangling effects of affect and reward on conflict-triggered control adjustments.
A dynamo driven by zonal jets at the upper surface: Applications to giant planets
Creators: name: Guervilly, Céline
name: Cardin, Philippe
name: Schaeffer, Nathanaël
Publisher: name: arXiv
Year: 2011
Subjects: subject: Geophysics (physics.geo-ph)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We present a dynamo mechanism arising from the presence of barotropically unstable zonal jet currents in a rotating spherical shell. The shear instability of the zonal flow develops in the form of a global Rossby mode, whose azimuthal wavenumber depends on the width of the zonal jets. We obtain self-sustained magnetic fields at magnetic Reynolds numbers greater than 1000. We show that the propagation of the Rossby waves is crucial for dynamo action. The amplitude of the axisymmetric poloidal magnetic field depends on the wavenumber of the Rossby mode, and hence on the width of the zonal jets. We discuss the plausibility of this dynamo mechanism for generating the magnetic field of the giant planets. Our results suggest a possible link between the topology of the magnetic field and the profile of the zonal winds observed at the surface of the giant planets. For narrow Jupiter-like jets, the poloidal magnetic field is dominated by an axial dipole whereas for wide Neptune-like jets, the axisymmetric poloidal field is weak.
description: published in Icarus
The ordinary of mass chants and the sequences
Creators: name: Hiley, David
Publisher: name: Universität Regensburg
Year: 1981
Subjects: subject: 780 Musik

description: Several writers – most notable among the recent ones being Max Lütolf, Rudolf Flotzinger and Edward Roesner – have commented on the choice of liturgical chants set in the additions to the main layer of Parisian polyphony in W1. The point of such comment is that by tracing concordances for those liturgical chants a clearer idea may be gained of the affiliations of W1 among the chant traditions of Britain and North France. The additions to W1 are more useful for this purpose than the main body of organa. The latter are settings of chants which were for the most part very widely known. Relatively few of them are unusual enough to permit speculation about the church for which W1 was compiled, or about the liturgical use to which it most nearly corresponds. So far as the organa are concerned, I do not feel that much advance can be made upon the careful discussion in Professor Roesner's article.
Ο αρχαίος αίνος ως «δοκιμασία» νοημοσύνης και ηθικής καλλιέργειας για μικρούς και μεγάλους
Creators: name: Ιωάννης Πετρόπουλος
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2006

description: Ο αρχαίος αίνος ως «δοκιμασία» νοημοσύνης και ηθικής καλλιέργειας για μικρούς και μεγάλους
description: ΚΕΙΜΕΝΑ, Issue 4 (July 2006)
Waves on the surface of the Orion molecular cloud
Creators: name: Berné, Olivier
name: Marcelino, Núria
name: Cernicharo, José
Publisher: name: arXiv
Year: 2010
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Mathematical Physics (math-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Massive stars influence their parental molecular cloud, and it has long been suspected that the development of hydrodynamical instabilities can compress or fragment the cloud. Identifying such instabilities has proved difficult. It has been suggested that elongated structures (such as the `pillars of creation') and other shapes arise because of instabilities, but alternative explanations are available. One key signature of an instability is a wave-like structure in the gas, which has hitherto not been seen. Here we report the presence of `waves' at the surface of the Orion molecular cloud near where massive stars are forming. The waves seem to be a Kelvin-Helmholtz instability that arises during the expansion of the nebula as gas heated and ionized by massive stars is blown over pre-existing molecular gas.
description: Preprint of publication in Nature
Μηδεια και Άλκηστις ή η μακραίωνη ιστορία της κατασκευής του αρνητικού γυναικείου στερεότυπου και η ανατροπή του μέσα από το παιδικό βιβλίο
Creators: name: Ευαγγελία Μουλά
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2006

description: Μηδεια και Άλκηστις ή η μακραίωνη ιστορία της κατασκευής του αρνητικού γυναικείου στερεότυπου και η ανατροπή του μέσα από το παιδικό βιβλίο
description: ΚΕΙΜΕΝΑ, Issue 4 (July 2006)
Probing individual weakly-coupled π-conjugated molecules on semiconductor surfaces
Creators: name: Münnich, Gerhard
name: Albrecht, Florian
name: Nacci, Christophe
name: Utz, Martin
name: Schuh, Dieter
name: Kanisawa, Kiyoshi
name: Fölsch, Stefan
name: Repp, Jascha
Publisher: name: Universität Regensburg
Year: 2012
Subjects: subject: adsorption, gallium arsenide, III-V semiconductors, indium compounds, organic compounds, organic-inorganic hybrid materials, scanning tunnelling spectroscopy
subject: 530 Physik
subject: 540 Chemie
subject: 68.43.Mn
subject: 68.43.-h

description: A weak perturbation of a single molecule by the supporting substrate is a key ingredient to molecular electronics. Here, we show that individual phthalocyanine molecules adsorbed on GaAs(110) and InAs(111)A surfaces represent prototypes for weakly coupled single-molecule/semiconductor hybrid systems. This is demonstrated by scanning tunneling spectroscopy and bias-dependent images that closely resemble orbital densities of the free molecule. This is in analogy to results for molecules decoupled from a metal substrate by an ultrathin insulating layer and proves a weak electronic molecule-substrate coupling. Therefore, such systems will allow single-molecule functionality to be combined with the versatility of semiconductor physics.
Ελληνική αρχαιότητα, μύθος και κλασικό παιδικό βιβλίο
Creators: name: Aλεξάνδρα Ζερβού
Publisher: name: ΚΕΙΜΕΝΑ
Year: 2006

description: Ελληνική αρχαιότητα, μύθος και κλασικό παιδικό βιβλίο
description: ΚΕΙΜΕΝΑ, Issue 4 (July 2006)
Canonical form of master equations and characterization of non-Markovianity
Creators: name: Hall, Michael J. W.
name: Cresser, James D.
name: Li, Li
name: Andersson, Erika
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Master equations govern the time evolution of a quantum system interacting with an environment, and may be written in a variety of forms. Time-independent or memoryless master equations, in particular, can be cast in the well-known Lindblad form. Any time-local master equation, Markovian or non-Markovian, may in fact also be written in a Lindblad-like form. A diagonalisation procedure results in a unique, and in this sense canonical, representation of the equation, which may be used to fully characterize the non-Markovianity of the time evolution. Recently, several different measures of non-Markovianity have been presented which reflect, to varying degrees, the appearance of negative decoherence rates in the Lindblad-like form of the master equation. We therefore propose using the negative decoherence rates themselves, as they appear in the canonical form of the master equation, to completely characterize non-Markovianity. The advantages of this are especially apparent when more than one decoherence channel is present. We show that a measure proposed by Rivas et al. is a surprisingly simple function of the canonical decoherence rates, and give an example of a master equation that is non-Markovian for all times t>0, but to which nearly all proposed measures are blind. We also give necessary and sufficient conditions for trace distance and volume measures to witness non-Markovianity, in terms of the Bloch damping matrix.
description: v2: Significant update, with many new results and one new author. 12 pages; v3: Minor clarifications, to appear in PRA; v4: matches published version