cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Uncovering electron scattering mechanisms in NiFeCoCrMn derived concentrated solid solution and high entropy alloys
Creators: name: Mu, Sai
name: Samolyuk, German D.
name: Wimmer, Sebastian
name: Troparevsky, Maria C.
name: Khan, Suffian N.
name: Mankovsky, Sergiy
name: Ebert, Hubert
name: Stocks, George M.
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: 530 Physik

description: Whilst it has long been known that disorder profoundly affects transport properties, recent measurements on a series of solid solution 3d-transition metal alloys reveal two orders of magnitude variations in the residual resistivity. Using ab initio methods, we demonstrate that, while the carrier density of all alloys is as high as in normal metals, the electron mean-free-path can vary from ~10 Å (strong scattering limit) to ~103 Å (weak scattering limit). Here, we delineate the underlying electron scattering mechanisms responsible for this disparate behavior. While site-diagonal, spin dependent, potential scattering is always dominant, for alloys containing only Fe, Co, and Ni the majority-spin channel experiences negligible disorder scattering, thereby providing a short circuit, while for Cr/Mn containing alloys both spin channels experience strong disorder scattering due to an electron filling effect. Somewhat surprisingly, other scattering mechanisms—including displacement, or size effect, scattering which has been shown to strongly correlate with such diverse properties as yield strength—are found to be relatively weak in most cases.
Spontaneous chirality selection and nonreciprocal spin wave in breathing-kagome antiferromagnets at zero field
Creators: name: Aoyama, Kazushi
name: Kawamura, Hikaru
Publisher: name: arXiv
Year: 2025
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: It has been known that the spin-wave dispersion, which is usually symmetric in the momentum space with respect to ${\bf q}=0$, can be asymmetric in the presence of the Dzyaloshinskii-Moriya (DM) interaction and an applied magnetic field. Here, we theoretically demonstrate that in $J_3$-dominant classical Heisenberg antiferromagnets on the breathing kagome lattice, the asymmetric spin-wave dispersion appears in a chiral phase due to non-uniform geometric phases acquired in the spin-wave propagation processes. This points to the emergence of a nonreciprocal spin wave in the absence of both the DM interaction and the magnetic field. Reflecting the asymmetry, positive-spin-chirality and negative-spin-chirality states, either one of which is selected in the low-temperature phase by the symmetry breaking, show different spin-wave dispersions, suggesting that the two energetically-degenerate chiral states can be distinguished by the spin-wave propagation.
description: 12 pages, 5 figures, 3 tables
Is tDCS an Adjunct Ergogenic Resource for Improving Muscular Strength and Endurance Performance? A Systematic Review
Creators: name: Machado, Sergio
name: Jansen, Petra
name: Almeida, Victor
name: Veldema, Jitka
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: 796 Sport

description: Exercise performance is influenced by many physical factors, such as muscle strength and endurance. Particularly in the physical fitness and sports performance contexts, there are many types of ergogenic aids to improve muscular strength and endurance performance, with non-athletes and even athletes using illegal drugs to reach the top. Thus, the development of innovative methods to aid in exercise performance is of great interest. One such method is transcranial direct current stimulation (tDCS). A systematic search was performed on the following databases, until January 2019; PubMed/MEDLINE, SCOPUS, and Pedro database. Studies on tDCS for muscular strength and endurance performance improvement in non-athletes and athletes adults were included. We compared the effect of anodal-tDCS (a-tDCS) to a sham/control condition on the outcomes muscular strength and endurance performance. We found 26 controlled trials. No trial mentions negative side effects of the intervention. The data show differences between the studies investigating muscle strength and the studies evaluating endurance, with regard to successful use of tDCS. Studies investigating the efficiency of tDCS on improving muscular strength demonstrate positive effects of a-tDCS in 66.7% of parameters tested. In contrast, in studies evaluating the effects of a-tDCS on improving endurance performance the a-tDCS revealed a significant improvement in only 50% of parameters assessed. The majority of the data shows consistently influence of a-tDCS on muscular strength, but not to endurance performance. The results of this systematic review suggest that a-tDCS can improve muscular strength, but not to endurance performance.
Internal Josephson Oscillations for Distinct Momenta Bose-Einstein Condensates
Creators: name: Lim, Lih-King
name: Troppenz, T.
name: Smith, C. Morais
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: The internal Josephson oscillations between an atomic Bose-Einstein condensate (BEC) and a molecular one are studied for atoms in a square optical lattice subjected to a staggered gauge field. The system is described by a Bose-Hubbard model with complex and anisotropic hopping parameters that are different for each species, i.e., atoms and molecules. When the flux per plaquette for each species is small, the system oscillates between two conventional zero-momentum condensates. However, there is a regime of parameters in which Josephson oscillations between a vortex-carrying atomic condensate (finite momentum BEC) and a conventional zero-momentum molecular condensate may be realized. The experimental observation of the oscillations between these qualitatively distinct BEC's is possible with state-of-the-art Ramsey interference techniques.
description: 8 pages, 6 figures
Coulomb engineering of the bandgap and excitons in two-dimensional materials
Creators: name: Raja, Archana
name: Chaves, Andrey
name: Yu, Jaeeun
name: Arefe, Ghidewon
name: Hill, Heather M.
name: Rigosi, Albert F.
name: Berkelbach, Timothy C.
name: Nagler, Philipp
name: Schüller, Christian
name: Korn, Tobias
name: Nuckolls, Colin
name: Hone, James
name: Brus, Louis E.
name: Heinz, Tony F.
name: Reichman, David R.
name: Chernikov, Alexey
Publisher: name: Universität Regensburg
Year: 2017
Subjects: subject: 530 Physik

description: The ability to control the size of the electronic bandgap is an integral part of solid-state technology. Atomically thin two-dimensional crystals offer a new approach for tuning the energies of the electronic states based on the unusual strength of the Coulomb interaction in these materials and its environmental sensitivity. Here, we show that by engineering the surrounding dielectric environment, one can tune the electronic bandgap and the exciton binding energy in monolayers of WS2 and WSe2 by hundreds of meV. We exploit this behaviour to present an in-plane dielectric heterostructure with a spatially dependent bandgap, as an initial step towards the creation of diverse lateral junctions with nanoscale resolution.
Fibrinogen Mediates Cadmium-induced Macrophage Activation and Increased Fibrinogen Serves as a Predictor of Cadmium Exposure in Chronic Obstructive Pulmonary Disease
Creators: name: Li, Fu Jun
Publisher: name: figshare
Year: 2022
Subjects: Cell Biology

description: Supplemental data including updated supplemental Fig. S1, S2, S3 and S4
Topological Schrödinger cats: Non-local quantum superpositions of topological defects
Creators: name: Dziarmaga, Jacek
name: Zurek, Wojciech H.
name: Zwolak, Michael
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Physics (quant-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Topological defects (such as monopoles, vortex lines, or domain walls) mark locations where disparate choices of a broken symmetry vacuum elsewhere in the system lead to irreconcilable differences. They are energetically costly (the energy density in their core reaches that of the prior symmetric vacuum) but topologically stable (the whole manifold would have to be rearranged to get rid of the defect). We show how, in a paradigmatic model of a quantum phase transition, a topological defect can be put in a non-local superposition, so that - in a region large compared to the size of its core - the order parameter of the system is "undecided" by being in a quantum superposition of conflicting choices of the broken symmetry. We demonstrate how to exhibit such a "Schrödinger kink" by devising a version of a double-slit experiment suitable for topological defects. Coherence detectable in such experiments will be suppressed as a consequence of interaction with the environment. We analyze environment-induced decoherence and discuss its role in symmetry breaking.
description: 7 pages, 4 figures
Homological mirror symmetry for the quintic 3-fold
Creators: name: Nohara, Yuichi
name: Ueda, Kazushi
Publisher: name: arXiv
Year: 2011
Subjects: subject: Symplectic Geometry (math.SG)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 53D37, 14J33

description: We prove homological mirror symmetry for the quintic Calabi-Yau 3-fold. The proof follows that for the quartic surface by Seidel (arXiv:math/0310414) closely, and uses a result of Sheridan (arXiv:1012.3238). In contrast to Sheridan's approach (arXiv:1111.0632), our proof gives the compatibility of homological mirror symmetry for the projective space and its Calabi-Yau hypersurface.
description: 29 pages, 6 figures. v2: revised following the suggestions of the referees
Chemical Ecology of the Parasitoid Wasp Genus Nasonia (Hymenoptera, Pteromalidae)
Creators: name: Mair, Magdalena M.
name: Ruther, Joachim
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: 590 Tiere (Zoologie)

description: The use of chemical cues and signals is essential for communication in insects. Wasps of the genus Nasonia (Hymenoptera, Pteromalidae) are gregarious parasitoids that lay their eggs into puparia of cyclorrhaphous flies. During their life cycle, various kinds of semiochemicals are used: (1) a male abdominal sex pheromone that attracts females and induces site fidelity in males, (2) a female-derived contact sex pheromone eliciting courtship behavior in males, (3) an oral male aphrodisiac eliciting receptivity signaling in females and causing a switch in the females' olfactory preferences, (4) chemicals derived from host habitat and host puparia used in olfactory host finding by female wasps, and (5) chemicals used by females to assess the quality and parasitization status of potential hosts. We review the literature on the chemical ecology of Nasonia spp. following the wasps' life cycle from emergence to oviposition. We depict biosynthetic pathways where available, discuss ecological implications, highlight differences among Nasonia species, summarize insights into their olfactory perception and associative learning abilities, and point out gaps in our understanding of the chemical ecology of these parasitoids to be addressed in future studies.
Relation of injuries and psychological symptoms in amateur soccer players
Creators: name: Jansen, Petra
name: Lehmann, Jennifer
name: Fellner, Birgit
name: Huppertz, Gunnar
name: Loose, Oliver
name: Achenbach, Leonard
name: Krutsch, Werner
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: 796 Sport

description: Objectives The first main goal of this study was to investigate the prevalence of depression and anxiety as well as self-compassion in a heterogeneous sample of male amateur soccer players. The second main goal of this study was the examination of the relationship between injuries and psychological factors in amateur soccer players. Methods Players were recruited from German amateur soccer clubs of the fourth to seventh league. 419 soccer players with the mean age of 22.88 years participated in the psychological and the injury assessment at the beginning of the season and at the end, 9 months later. For the psychological assessment, depression and anxiety rate as well as self-compassion was analysed. Furthermore, the frequencies of injuries were registered. Results The results showed that players of the highest amateur league, the fourth league in German soccer, showed significantly higher anxiety values than players from a lower league (p=0.013). There were no differences in depression values dependent on the league. Furthermore, players who suffered from an injury before the start of the season demonstrated higher anxiety values (p=0.027). This result was independent of the respective league. Conclusion The results of this study demonstrate that even in higher amateur soccer the anxiety level of the players varies between soccer players of different leagues. Because an injury before the start of the season influenced the anxiety level, a psychological treatment during injury should be considered. Summary box Even in higher amateur soccer the anxiety level of the players varies between soccer players of different leagues. Psychological factors are also in lower soccer levels related to injuries. The possible relation of psychological and medical issues must be also investigated in amateur soccer players.
Residue classes containing an unexpected number of primes
Creators: name: Fiorilli, Daniel
Publisher: name: arXiv
Year: 2010
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11N13

description: We fix a non-zero integer $a$ and consider arithmetic progressions $a \bmod q$, with $q$ varying over a given range. We show that for certain specific values of $a$, the arithmetic progressions $a \bmod q$ contain, on average, significantly fewer primes than expected.
description: 18 pages. Added a few remarks, changed the numbering of sections, slightly improved results, and made a few corrections
A population-based multigenerational family co-aggregation study of severe infections and obsessive-compulsive disorder
Creators: name: Brikell, Isabell
name: de Schipper, Elles
name: Mataix-Cols, David
name: Crowley, James J
name: Pol-Fuster, Josep
name: Larsson, Henrik
name: Hesselmark, Eva
name: Fernández de la Cruz, Lorena
name: D'Onofrio, Brian M
name: Lichtenstein, Paul
name: Kuja-Halkola, Ralf
name: Chang, Zheng
name: Beucke, Jan
Publisher: name: Elsevier
Year: 2024

description: BACKGROUND: Postinfectious autoimmune processes have been proposed as potential causal factors for obsessive-compulsive disorder (OCD). This large population-based study aimed to clarify the co-aggregation pattern between severe infections and OCD across clusters of relatives with varying degrees of relatedness.
METHODS: We identified 4,916,898 individuals born in Sweden between 1960 and 2008 and followed them until 2020. Each individual was linked to their first- and second-degree relatives, including monozygotic (MZ) and dizygotic (DZ) twins, mothers, fathers, full siblings, maternal and paternal half siblings, aunts, uncles, and cousins. OCD and infection diagnoses from inpatient and specialized outpatient units were retrieved from the Swedish National Patient Register. We compared the risk of OCD in relatives of probands with severe infections to those of probands without severe infections. Cox proportional hazard regression models, incorporating time-varying exposures, were used to estimate hazard ratios (HRs). Dose-response associations were examined using logistic regression models.
RESULTS: Relatives of probands with severe infections exhibited a higher risk of OCD, increasing with genetic relatedness, with HRs (95% CI) ranging from 1.46 (1.07-1.98) in MZ twins to 1.10 (1.09-1.11) in cousins. The results remained robust after adjusting for severe infections among relatives, OCD in probands, and comorbid autoimmune disorders in both probands and relatives. A dose-response association was observed between the number of infections in the probands and their odds of OCD, as well as in their relatives.
CONCLUSIONS: The results strongly suggest that the association between severe infections and OCD may be largely driven by shared genetic factors.
Syzygies of surfaces of general type
Creators: name: Banagere, P.
name: Hanumanthu, Krishna
Publisher: name: arXiv
Year: 2010
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 13D02, 14C20, 14J29

description: We prove new results on projective normality, normal presentation and higher syzygies for a surface of general type $X$ embedded by adjoint line bundles $L_r = K + rB$, where $B$ is a base point free, ample line bundle. Our main results determine the $r$ for which $L_r$ has $N_p$ property. In corollaries, we will relate the bounds on $r$ to the regularity of $B$. Examples in the last section show that several results are optimal.
description: 29 pages. Minor corrections and some changes in exposition. To be published in Geometriae Dedicata
Isolation of Subtype 3c, 3e and 3f-Like Hepatitis E Virus Strains Stably Replicating to High Viral Loads in an Optimized Cell Culture System
Creators: name: Schemmerer, Mathias
name: Johne, Reimar
name: Erl, Monika
name: Jilg, Wolfgang
name: Wenzel, Jürgen J.
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: hepatitis E virus; cell culture; whole genome; wild-type HEV isolation; high viral loads
subject: 610 Medizin

description: The hepatitis E virus (HEV) is transmitted via the faecal–oral route in developing countries (genotypes 1 and 2) or through contaminated food and blood products worldwide (genotypes 3 and 4). In Europe, HEV subtypes 3c, 3e and 3f are predominant. HEV is the leading cause of acute hepatitis globally and immunocompromised patients are particularly at risk. Because of a lack of cell culture systems efficiently propagating wild-type viruses, research on HEV is mostly based on cell culture-adapted isolates carrying uncommon insertions in the hypervariable region (HVR). While optimizing the cell culture system using the cell culture-adapted HEV strain 47832c, we isolated three wild-type strains derived from clinical specimens representing the predominant spectrum of HEV in Europe. The novel isolates 14-16753 (3c), 14-22707 (3e) and 15-22016 (3f-like) replicate to high viral loads of 108, 109 and 106.5 HEV RNA copies/mL at 14 days post-inoculation, respectively. In addition, they could be kept as persistently infected cell cultures with constant high viral loads (~109 copies/mL) for more than a year. In contrast to the latest isolates 47832c, LBPR-0379 and Kernow-C1, the new isolates do not carry genome insertions in the HVR. Optimization of HEV cell culture identified amphotericin B, distinct salts and fetal calf serum (FCS) as important medium supplements. Overconfluent cell layers increased infectivity and virus production. PLC/PRF/5, HuH-7-Lunet BLR, A549 and HepG2/C3A supported replication with different efficiencies. The novel strains and optimized cell culture system may be useful for studies on the HEV life cycle, inactivation, specific drug and vaccine development.
Supersymmetry of consistent massive truncations of IIB supergravity
Creators: name: Liu, James T.
name: Szepietowski, Phillip
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We discuss the supersymmetry and fermionic sector of the recently obtained consistent truncations of IIB supergravity containing massive modes. In particular, we present the general form of the five-dimensional N = 4 supersymmetry transformations and equations of motion for the fermions arising in the reduction of IIB theory on T^{1,1} which contains all modes invariant under the SU(2) x SU(2) isometry group. The N = 4 reduction can be further truncated to two different N = 2 sub-sectors. For each of these, we present the N = 2 fermionic supersymmetry transformations and corresponding superpotentials. As an application, we obtain the explicit Killing spinors of the Klebanov-Strassler solution and comment on the relation to the ansatz of Papadopoulos and Tseytlin. We also demonstrate the applicability of consistent truncations on squashed Sasaki-Einstein manifolds to a class of flux compactifications, focusing on a recent solution describing the geometry of gaugino condensation on wrapped D7 branes and which possesses dynamic SU(2) structure.
description: v2: minor typos corrected, references added, v3: significant additions to include fermion equations of motion, journal version
Exciton broadening in WS2 /graphene heterostructures
Creators: name: Hill, Heather M.
name: Rigosi, Albert F.
name: Raja, Archana
name: Chernikov, Alexey
name: Roquelet, Cyrielle
name: Heinz, Tony F.
Publisher: name: Universität Regensburg
Year: 2017
Subjects: subject: 530 Physik

description: We have used optical spectroscopy to observe spectral broadening of WS2 exciton reflectance peaks in heterostructures of monolayer WS2 capped with mono- to few-layer graphene. The broadening is found to be similar for the A and B excitons and on the order of 5–10 meV. No strong dependence on the number of graphene layers was observed within experimental uncertainty. The broadening can be attributed to charge- and energy-transfer processes between the two materials, providing an observed lower bound for the corresponding time scales of 65 fs.
Les conceptions de l’autonomie / The conceptions of autonomy / Le concezioni di autonomia
Creators: name: De Terssac, Gilbert
name: Maggi, Bruno
Publisher: name: Alma Mater Studiorum - Università di Bologna
Year: 2022
Subjects: M-PSI/06 Psicologia del lavoro e delle organizzazioni
SECS-P/08 Economia e gestione delle imprese
SECS-P/10 Organizzazione aziendale
SPS/09 Sociologia dei processi economici e del lavoro

description: Autonomy has been broadly discussed in the face of the transformations in work processes, from the alleged overcoming of the Fordist model at the end of the twentieth century to the changes induced by information technology in the 2000s. Nevertheless, the widespread definitions of autonomy have generally been distant from the term’s etymological meaning, which indicates autonomy as the subject’s capability to produce her own rules and, therefore, to manage her own processes of action. This contribution discusses the various conceptions of autonomy, also in relation to the different interpretations of cooperation and the different ways of conceiving and planning the structuring of work processes. It is a discussion that clarifies and explains the extensive literature on the subject while maintaining its topicality.
Strong coupling and non-Markovian effects in the statistical notion of temperature
Creators: name: Moreno, Camilo
name: Urbina, Juan Diego
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: 530 Physik

description: We investigate the emergence of temperature T in the system-plus-reservoir paradigm starting from the fundamental microcanonical scenario at total fixed energy E where, contrary to the canonical approach, T=T(E) is not a control parameter but a derived auxiliary concept. As shown by Schwinger for the regime of weak coupling γ between subsystems, T(E) emerges from the saddle-point analysis leading to the ensemble equivalence up to corrections O(1/√N) in the number of particles N that defines the thermodynamic limit. By extending these ideas for finite γ, while keeping N→∞, we provide a consistent generalization of temperature T(E,γ) in strongly coupled systems, and we illustrate its main features for the specific model of quantum Brownian motion where it leads to consistent microcanonical thermodynamics. Interestingly, while this T(E,γ) is a monotonically increasing function of the total energy E, its dependence with γ is a purely quantum effect notably visible near the ground-state energy and for large energies differs for Markovian and non-Markovian regimes.
Social dynamics and nationhood in employment politics in the Trepça mining complex in Socialist Kosovo (1960s)
Creators: name: Troch, Pieter
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: Kosovo, Socialist Yugoslavia, employment politics, Trepça, nationhood
subject: 940 Geschichte Europas

description: This article analyses the interconnection of socio-economic divisions and nationhood in Socialist Kosovo through a case-study of employment politics in the Trepça mining complex during the 1960s. The article first describes the shifting cadre politics in Trepça, which aimed to increase the degree of skills of the work collective and to address the dramatic under-representation of Albanians in management and specialist positions. It then analyses the departure of Serb and Montenegrin specialists from the enterprise and the internal dispute over the proportional relevance of socio-economic and national grounds for this trend. The second half of the article situates these developments against two levels of social division in the enterprise: vertical social divisions between manual production workers and specialist cadres and horizontal divisions at the top management level. The article argues that the divisions between low-skilled production workers and management personnel was not politically relevant. Such vertical social divisions were depoliticised and denationalised. The outspoken national dimension of cadre politics for specialist personnel and the pluralist tendencies in the management culture of Yugoslav enterprises during the late 1960s, on the other hand, nationalised and politicised the competition between a new generation of Albanian technically-schooled specialists and the predominantly Serb, politically-appointed managers in function.
description: nach Embargo automatisch öffentlich zugänglich ab 1.5.2020
The Tutte polynomial of the Sierpinski and Hanoi graphs
Creators: name: Donno, Alfredo
name: Iacono, Donatella
Publisher: name: arXiv
Year: 2010
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05C31, 05C15, 05C30, 05C38, 20E08

description: We study the Tutte polynomial of two infinite families of finite graphs: the Sierpiński graphs, which are finite approximations of the well-known Sierpiński gasket, and the Schreier graphs of the Hanoi Towers group $H^{(3)}$ acting on the rooted ternary tree. For both of them, we recursively describe the Tutte polynomial and we compute several special evaluations of it, giving interesting results about the combinatorial structure of these graphs.
description: 30 pages; title changed; revised exposition in the second version but results unchanged. arXiv admin note: substantial text overlap with arXiv:1010.2902
Gilbert damping in noncollinear magnetic systems
Creators: name: Mankovsky, S.
name: Wimmer, S.
name: Ebert, H.
Publisher: name: Universität Regensburg
Year: 2018
Subjects: subject: 530 Physik

description: The modification of the magnetization dissipation or Gilbert damping caused by an inhomogeneous magnetic structure and expressed in terms of a wave vector dependent tensor α––(→q) is investigated by means of linear response theory. A corresponding expression for α––(→q) in terms of the electronic Green function has been developed giving in particular the leading contributions to the Gilbert damping linear and quadratic in q. Numerical results for realistic systems are presented that have been obtained by implementing the scheme within the framework of the fully relativistic KKR (Korringa-Kohn-Rostoker) band structure method. Using the multilayered system (Cu/Fe1−xCox/Pt)n as an example for systems without inversion symmetry we demonstrate the occurrence of nonvanishing linear contributions. For the alloy system bcc Fe1−xCox having inversion symmetry, on the other hand, only the quadratic contribution is nonzero. As it is shown, this quadratic contribution does not vanish even if the spin-orbit coupling is suppressed, i.e., it is a direct consequence of the noncollinear spin configuration.
The Kontsevich constants for the volume of the moduli of curves and topological recursion
Creators: name: Chapman, Kevin M.
name: Mulase, Motohico
name: Safnuk, Brad
Publisher: name: arXiv
Year: 2010
Subjects: subject: Algebraic Geometry (math.AG)
subject: Mathematical Physics (math-ph)
subject: Combinatorics (math.CO)
subject: Symplectic Geometry (math.SG)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 14N35, 05C30, 53D30, 11P21 (Primary) 81T30 (Secondary)

description: We give an Eynard-Orantin type topological recursion formula for the canonical Euclidean volume of the combinatorial moduli space of pointed smooth algebraic curves. The recursion comes from the edge removal operation on the space of ribbon graphs. As an application we obtain a new proof of the Kontsevich constants for the ratio of the Euclidean and the symplectic volumes of the moduli space of curves.
description: 37 pages with 20 figures
Spin-wave stiffness and micromagnetic exchange interactions expressed by means of the KKR Green function approach
Creators: name: Mankovsky, S.
name: Polesya, S.
name: Ebert, H.
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: 530 Physik

description: We represent an approach to calculate micromagnetic model parameters such as the tensor of exchange stiffness, Dzyaloshinskii-Moriya interaction (DMI), as well as spin-wave stiffness. The scheme is based on the fully relativistic Korringa-Kohn-Rostoker Green function (KKR-GF) technique and can be seen as a relativistic extension of the work of Lichtenstein et al. [J. Magn. Magn. Mater. 67, 65 (1987)]. The expression for Dzα elements of DMI differ from the expressions for Dxα and Dyα elements as the former are derived via second-order perturbation term of the energy caused by spin-spiral while the latter are associated with the first-order term. Corresponding numerical results are compared with those obtained using other schemes reported in the literature.
Boundary behavior of the Kobayashi distance in pseudoconvex Reinhardt domains
Creators: name: Warszawski, Tomasz
Publisher: name: arXiv
Year: 2011
Subjects: subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 32F45 (Primary) 32A07 (Secondary)

description: We prove that the Kobayashi distance near boundary of a pseudoconvex Reinhardt domain $D$ increases asymptotically at most like $-\log d_D+C$. Moreover, for boundary points from $\text{int}\bar{D}$ the growth does not exceed $1/2\log(-\log d_D)+C$. The lower estimate by $-1/2\log d_D+C$ is obtained under additional assumptions of $\mathcal C^1$-smoothness of a domain and a non-tangential convergence.
description: 16 pages. To appear in Mich. Math. J
Revealing forest harvesting effects on large peakflows in rain-on-snow environment with new stochastic physics
Creators: name: Rong, WeiTao
Publisher: name: University of British Columbia
Year: 2019

description: Using nine pairs of control-treatment watersheds with varying climate, physiography, and harvesting practices in the Rain-On-Snow (ROS) environment of the Pacific Northwest region, this thesis demonstrates the linkage between environmental control and the sensitivity of peakflow response to harvesting effects. Compared to previous paired watershed studies in ROS environment, this study, for the first time, employed an experimental design of Frequency Pairing to isolate the effects of disturbances on systems’ response. The use of frequency distributions for evaluating the relation between forest harvesting and peakflows is a well-established framework outside forest hydrology literature. The results show how harvesting can dramatically increase the magnitude of all peakflows on record and how such effects can increase with increasing return periods, as a consequence of substantial increases to the mean and variance of the peakflow frequency distribution. Most critically, peakflows with return period larger than 10 years can increase in frequency, where the larger the peakflow event the more frequent it may become. The sensitivity of the upper tail of the frequency distribution of peakflows was found to be linked to the physiographic and climatic characteristics via a unifying synchronization / desynchronization spatial scaling mechanism that controls the generation of rain-on-snow runoff. This new physically-based stochastic hydrology understanding on the response of watersheds in ROS environments runs counter the deterministic prevailing wisdom of forest hydrology, which presumes a limited and diminishing role of forest cover as the magnitude of the peakflow event increases. By demonstrating the need for invoking the dimension of frequency in the understanding and prediction of the effects of harvesting on peakflows, this study added another brick to the pile of evidence in calling for the abandonment of the outdated pure deterministic hypotheses and experimental designs that have misguided forest hydrology research for over a century on this topic.
Microscopic model for Bose-Einstein condensation and quasiparticle decay
Creators: name: Fischer, Tim
name: Duffe, Sebastian
name: Uhrig, Götz S.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Sufficiently dimerized quantum antiferromagnets display elementary S=1 excitations, triplon quasiparticles, protected by a gap at low energies. At higher energies, the triplons may decay into two or more triplons. A strong enough magnetic field induces Bose-Einstein condensation of triplons. For both phenomena the compound IPA-CuCl3 is an excellent model system. Nevertheless no quantitative model was determined so far despite numerous studies. Recent theoretical progress allows us to analyse data of inelastic neutron scattering (INS) and of magnetic susceptibility to determine the four magnetic couplings J1=-2.3meV, J2=1.2meV, J3=2.9meV and J4=-0.3meV. These couplings determine IPA-CuCl3 as system of coupled asymmetric S=1/2 Heisenberg ladders quantitatively. The magnetic field dependence of the lowest modes in the condensed phase as well as the temperature dependence of the gap without magnetic field corroborate this microscopic model.
description: 6 pages, 5 figures
Yangians and quantum loop algebras
Creators: name: Gautam, Sachin
name: Toledano-Laredo, Valerio
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Algebra (math.QA)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics

description: Let g be a complex, semisimple Lie algebra. Drinfeld showed that the quantum loop algebra U_h(Lg) of g degenerates to the Yangian Y_h(g). We strengthen this result by constructing an explicit algebra homomorphism Phi defined over Q[[h]] from U_h(Lg) to the completion of Y_h(g) with respect to its grading. We show moreover that Phi becomes an isomorphism when the quantum loop algebra is completed with respect to its its evaluation ideal. We construct a similar homomorphism for g=gl_n and show that it intertwines the geometric actions of U_h(L gl_n) and Y(gl_n) on the equivariant K-theory and cohomology of the variety of n-step flags in C^d constructed by Ginzburg and Vasserot.
description: 55 pages. Introduction expanded, exposition in section 4 improved, isomorphism between completions for gl(n) added in section 7, a few references added, minor changes throughout. Final version. Published online in Selecta Mathematica
Conjugate Function Method for Numerical Conformal Mappings
Creators: name: Hakula, Harri
name: Quach, Tri
name: Rasila, Antti
Publisher: name: arXiv
Year: 2011
Subjects: subject: Numerical Analysis (math.NA)
subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 30C30 (Primary) 65E05, 31A15, 30C85 (Secondary)

description: We present a method for numerical computation of conformal mappings from simply or doubly connected domains onto so-called canonical domains, which in our case are rectangles or annuli. The method is based on conjugate harmonic functions and properties of quadrilaterals. Several numerical examples are given.
description: 23 pages, 15 figures, 5 tables
Integrating data for learning disabilities service providers: are the barriers and solutions technical or organisational?
Creators: name: Kruschwitz, Udo
name: Musgrave, S.
name: O'Neill, D.
name: Gekas, J.
name: Mann, H.
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: data sharing; interagency working; learning disability
subject: 020 Bibliotheks- und Informationswissenschaft

description: Since the publication of the Government White Paper 'Valuing People: a new strategy for learning disability for the 21st century', the responsibility for providing health care for people with learning disabilities has shifted rapidly to primary care.1 However, people with learning disabilities are supported by a disparate group of providers, from health care through local authorities to the voluntary sector, with resultant difficulties in providing seamless care. There would seem to be considerable potential for 'joined-up' data and information services to improve this situation, and Semantic Web technologies offer many enticing possibilities in this regard. However, to be effective, many organisational and policy issues have to be addressed; not least among these is the concern of patient confidentiality. This is particularly pertinent given that people with learning disabilities might be less able to make informed decisions. The approach that this paper takes is to review the policy and service scenarios that would benefit from 'joined-up' data, and then, based on user feedback from a series of seminars with stakeholders on these issues, explore what works well, what works less well, and to offer suggestions for future developments.
Temperature dependent electronic transport in concentrated solid solutions of the 3d-transition metals Ni, Fe, Co and Cr from first principles
Creators: name: Samolyuk, G. D.
name: Mu, S.
name: May, A. F.
name: Sales, B. C.
name: Wimmer, S.
name: Mankovsky, S.
name: Ebert, H.
name: Stocks, G. M.
Publisher: name: Universität Regensburg
Year: 2018
Subjects: subject: 530 Physik

description: An approach previously developed for the calculation of transport coefficients via the Mott relations is applied to the calculation of finite temperature transport properties of disordered alloys—electrical resistivity and the electronic part of thermal conductivity. The coherent-potential approximation is used to treat chemical disorder as well as other sources of electron scattering, i.e., temperature induced magnetic moment fluctuations and lattice vibrations via the alloy analogy model. This approach, which treats all forms of disorder on an equal first-principles footing, is applied to the calculation of transport properties of a series of fcc concentrated solid solutions of the 3d-transition metals Ni, Fe, Co, and Cr. For the nonmagnetic alloys Ni0.8Cr0.2 and Ni0.33Co0.33Cr0.3, the combined effects of chemical disorder and electron-lattice vibrations scattering result in a monotonic increase in the resistivity as a function of temperature from an already large, T=0, residual resistivity. For magnetic Ni0.5Co0.5,Ni0.5Fe0.5, and Ni0.33Fe0.33Co0.33, the residual resistivity of which is small, additional electron scattering from temperature induced magnetic moment fluctuations results in a further rapid increase of the resistivity as a function of temperature. The electronic part of the thermal conductivity in nonmagnetic Ni0.8Cr0.2 and Ni0.33Co0.33Cr0.33 monotonically increases with temperature. This behavior is a result of the competition between a reduction in the conductivity due to electron-lattice vibrations scattering and temperature induced increase in the number of carriers. In the magnetic alloys, electron scattering from magnetic fluctuations leads to an initial rapid decrease in thermal conductivity until this is overcome by an increasing number of carriers at temperatures slightly below the Curie temperature. Similar to the resistivity above TC, the electronic parts of the thermal conductivities are close to each other in all alloys studied.
title: Psoriatic arthriti : an unusual onset. About two clinical cases
title: Un rhumatisme psoriasique à début atypique : à propos de deux cas
Creators: name: Chitachen, Hanane
Publisher: name: Revue Marocaine de Rhumatologie (RMR)
Year: 2021
Subjects: Rhumatisme psoriasique; Ostéolyse; Critères radiologiques.

description: Psoriatic arthritis is a spondyloarthritis which combines axial or peripheral joint damage, enthesic damage and psoriasis. When the psoriasis is absent and articular manifestations are atypical, the diagnosis becomes very difficult unless one finds particular radiological manifestations which are specific to it. We report two cases without skin psoriasis. In the first case, the revealing involvement is bilateral metatarsalgia with osteolysis of the 5 th metatarsal head. MRI found a sacroiliitis and symphysis pubis which were asymptomatic. The patient is HLA B27 negative and responds perfectly to non steroidal anti-inflammatory. In the second case, the patient has dactylics from the left thumb and painful. X-ray showed osteolysis of the first phalanx. Histological study found nail psoriasis.
description: Le rhumatisme psoriasique est une spondyloarthrite qui associe une atteinte articulaire, enthésique et un psoriasis cutané. En l’absence d’atteinte cutanée, le diagnostic devient difficile. Nous rapportons deux cas atypiques de RP sans psoriasis cutané. Dans le premier cas, l’atteinte révélatrice est une métatarsalgie bilatérale avec une ostéolyse bilatérale des 5èmes têtes métatarsiennes. On découvre, à postériori à l’IRM, une sacroiliite et une atteinte de la symphyse pubienne qui étaient asymptomatiques. Le patient est HLA B27 négatif et répond parfaitement aux anti-inflammatoires non stéroïdiens. Dans le 2ème cas, il s’agit d’un patient qui a une dactylite isolée et douloureuse du pouce gauche. La radiographie a montré une ostéolyse de la 1ère phalange et l’onyxis du pouce s’est avéré un psoriasis unguéal.
Deriving query suggestions for site search
Creators: name: Kruschwitz, Udo
name: Lungley, D.
name: Albakour, M. D.
name: Song, D.
Publisher: name: Universität Regensburg
Year: 2013
Subjects: subject: 020 Bibliotheks- und Informationswissenschaft

description: Modern search engines have been moving away from simplistic interfaces that aimed at satisfying a user's need with a single‐shot query. Interactive features are now integral parts of web search engines. However, generating good query modification suggestions remains a challenging issue. Query log analysis is one of the major strands of work in this direction. Although much research has been performed on query logs collected on the web as a whole, query log analysis to enhance search on smaller and more focused collections has attracted less attention, despite its increasing practical importance. In this article, we report on a systematic study of different query modification methods applied to a substantial query log collected on a local website that already uses an interactive search engine. We conducted experiments in which we asked users to assess the relevance of potential query modification suggestions that have been constructed using a range of log analysis methods and different baseline approaches. The experimental results demonstrate the usefulness of log analysis to extract query modification suggestions. Furthermore, our experiments demonstrate that a more fine‐grained approach than grouping search requests into sessions allows for extraction of better refinement terms from query log files.
On the Essential Spectrum of Phase-Space Anisotropic Pseudodifferential Operators
Creators: name: Mantoiu, M.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Spectral Theory (math.SP)
subject: Operator Algebras (math.OA)
subject: FOS: Mathematics
subject: 35S05, 81Q10, 46L55, 47C15

description: A phase-space anisotropic operator in H=L^2(R^n) is a self-adjoint operator whose resolvent family belongs to a natural C*-completion of the space of Hörmander symbols of order zero. Equivalently, each member of the resolvent family is norm-continuous under conjugation with the Schrödinger unitary representation of the Heisenberg group. The essential spectrum of such a phase-space anisotropic operator is the closure of the union of usual spectra of all its "phase-space asymptotic localizations", obtained as limits over diverging ultrafilters of R^{n}\times R^n-translations of the operator. The result extends previous analysis of the purely configurational anisotropic operators,for which only the behavior at infinity in R^n was allowed to bo non-trivial.
description: 10 pages
Generation of optical beams with desirable orbital angular momenta by transformation media
Creators: name: Shu, Weixing
name: Song, Dongmo
name: Tang, Zhixiang
name: Luo, Hailu
name: Ke, Yougang
name: Lü, Xiaofang
name: Wen, Shuangchun
name: Fan, Dianyuan
Publisher: name: arXiv
Year: 2010
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We propose a scheme to controllably convert the wavefront of an arbitrary incident beam into a helical one by compact transformation slabs, thus enabling the output beam to carry desirable orbital angular momentum (OAM). First, based on transformation optics, a three-dimensional (3D) phase transformation between any two wavefronts by °at transformation media is established and then used to mold a wavefront of Gaussian beam into a helical one. Second, 3D FDTD simulations are performed to confirm the spiraling evolutions of the resultant field and phase, clearly demonstrating OAM generated. Further theoretical analyses show that the refractive index exhibiting a helical distribution leads to the oppositely spiral phase front and that it is feasible to produce desirable OAM by generators of unit OAM. The results not only provide an additional way to manipulate phase and photon OAM, but reciprocally shed further light on the phase structure of helical beams, which leads to a new transformation way by a surface.
description: 6 pages, 5 figures; Phys. Rev. A, 2012
Hidden Mn magnetic-moment disorder and its influence on the physical properties of medium-entropy NiCoMn solid solution alloys
Creators: name: Mu, Sai
name: Yin, J.
name: Samolyuk, G. D.
name: Wimmer, S.
name: Pei, Z.
name: Eisenbach, M.
name: Mankovsky, S.
name: Ebert, H.
name: Stocks, G. M.
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: 530 Physik

description: The ab initio Korringa-Kohn-Rostoker method combined with the coherent potential approximation (CPA) was employed to investigate the electronic, magnetic, and transport properties of medium-entropy face-centered-cubic (fcc) NiCoMn solid solution alloys. By comparing the CPA electronic structure with that from supercell calculations, we uncovered an unconventional CPA ground state, which correctly distinguishes two equally populated Mn CPA components—with large spin moments but opposite orientations. Using the spin spiral calculations, we further demonstrated that this ground state is most energetically favorable in the presence of spin noncollinearity, and no significant longitudinal spin fluctuation is observed, justifying the applicability of the Heisenberg model. The finite-temperature magnetism was further studied using different approximations based on the Heisenberg model, and we found the Mn moments to be fully disordered at low temperature due to a small net effective Weiss field on Mn. In addition, the magnetic effect on the electron scattering at finite temperatures was evaluated and compared with other scattering mechanisms. Since the magnetization-induced electron scattering is almost saturated in the ground state, (full) spin disorder only yields a small addition to the resistivity, whereas the thermal displacements increase it modestly. Finally, we elucidate the role of hydrostatic pressure on the magnetic and transport properties. These findings reflect the importance of the magnetic signatures on the physical properties of alloys, and they provide a window into magnetism-controlled electronic structure and energy dissipation.