cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Quantum Double Model with Boundary: Condensations and Symmetries
Creators: name: Beigi, Salman
name: Shor, Peter W.
name: Whalen, Daniel
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: Associated to every finite group, Kitaev has defined the quantum double model for every orientable surface without boundary. In this paper, we define boundaries for this model and characterize condensations; that is, we find all quasi-particle excitations (anyons) which disappear when they move to the boundary. We then consider two phases of the quantum double model corresponding to two groups with a domain wall between them, and study the tunneling of anyons from one phase to the other. Using this framework we discuss the necessary and sufficient conditions when two different groups give the same anyon types. As an application we show that in the quantum double model for S_3 (the permutation group over three letters) there is a chargeon and a fluxion which are not distinguishable. This group is indeed a special case of groups of the form of the semidirect product of the additive and multiplicative groups of a finite field, for all of which we prove a similar symmetry.
description: 31 pages, 7 figures, contains results of arXiv:1002.4930 and new stuff
On tail trend detection: modeling relative risk
Creators: name: de Haan, Laurens
name: Tank, Albert Klein
name: Neves, Cláudia
Publisher: name: arXiv
Year: 2011
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics

description: The climate change dispute is about changes over time of environmental characteristics (such as rainfall). Some people say that a possible change is not so much in the mean but rather in the extreme phenomena (that is, the average rainfall may not change much but heavy storms may become more or less frequent). The paper studies changes over time in the probability that some high threshold is exceeded. The model is such that the threshold does not need to be specified, the results hold for any high threshold. For simplicity a certain linear trend is studied depending on one real parameter. Estimation and testing procedures (is there a trend?) are developed. Simulation results are presented. The method is applied to trends in heavy rainfall at 18 gauging stations across Germany and The Netherlands. A tentative conclusion is that the trend seems to depend on whether or not a station is close to the sea.
description: 38 pages
Endperiodic Automorphisms of Surfaces and Foliations
Creators: name: Cantwell, John
name: Conlon, Lawrence
name: Fenley, Sergio R.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Geometric Topology (math.GT)
subject: FOS: Mathematics
subject: 57R30 (primary), 37E30 (secondary)

description: We extend the unpublished work of M. Handel and R. Miller on the classification, up to isotopy, of endperiodic automorphisms of surfaces. We give the Handel-Miller construction of the geodesic laminations, give an axiomatic theory for pseudo-geodesic lamaniations, show the geodesic laminations satisfy the axioms, and prove that paeudo-geodesic laminations satisfying our axioms are ambiently isotopic to the geodesic laminations. The axiomatic approach allows us to show that the given endperiodic automorphism is isotopic to a smooth endperiodic automorphism preserving smooth laminations ambiently isotopic to the original ones. Using the axioms, we also prove the "transfer theorem" for foliations of 3-manifolds., namely that, if two depth one foliations are transverse to a common one-dimensional foliation whose monodromy on the noncompact leaves of the first foliation exhibits the nice dynamics of Handel-Miller theory, then the transverse one-dimensional foliation also induces monodromy on the noncompact leaves of the second foliation exhibiting the same nice dynamics. Our theory also applies to surfaces with infinitely many ends.
description: Added Sergio Fenley as author. Moved material from Section 12.6 to a new Section 6.7. Rewrote Section 7. Deleted material from Section 6.1 and combined Sections 6.1 and 6.2 into new Section 6.1. Rewrote Section 4.6. Corrected typos and errors and improved exposition
Isotopes of Hurwitz algebras
Creators: name: Darpö, Erik
Publisher: name: arXiv
Year: 2010
Subjects: subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics
subject: 17A60 (17A35, 17A75)

description: We study the class of all algebras that are isotopic to a Hurwitz algebra. Isomorphism classes of such algebras are shown to correspond to orbits of a certain group action. A complete, geometrically intuitive description of the category of isotopes of Hamilton's quaternions is given. As an application, we demonstrate how some results concerning the classification of finite-dimensional composition algebras can be deduced from our general results.
description: 11 pages, final version
An assessment of catalytic residue 3D ensembles for the prediction of enzyme function
Creators: name: Merkl, Rainer
name: Žváček, Clemens
name: Heizinger, Leonhard
name: Friedrichs, Gerald
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: Catalytic site; Pose comparison; Enzyme function; Enzyme classification
subject: 570 Biowissenschaften, Biologie

description: Background The central element of each enzyme is the catalytic site, which commonly catalyzes a single biochemical reaction with high specificity. It was unclear to us how often sites that catalyze the same or highly similar reactions evolved on different, i. e. non-homologous protein folds and how similar their 3D poses are. Both similarities are key criteria for assessing the usability of pose comparison for function prediction. Results We have analyzed the SCOP database on the superfamily level in order to estimate the number of non-homologous enzymes possessing the same function according to their EC number. 89 % of the 873 substrate-specific functions (four digit EC number) assigned to mono-functional, single-domain enzymes were only found in one superfamily. For a reaction-specific grouping (three digit EC number), this value dropped to 35 %, indicating that in approximately 65 % of all enzymes the same function evolved in two or more non-homologous proteins. For these isofunctional enzymes, structural similarity of the catalytic sites may help to predict function, because neither high sequence similarity nor identical folds are required for a comparison. To assess the specificity of catalytic 3D poses, we compiled the redundancy-free set ENZ_SITES, which comprises 695 sites, whose composition and function are well-defined. We compared their poses with the help of the program Superpose3D and determined classification performance. If the sites were from different superfamilies, the number of true and false positive predictions was similarly high, both for a coarse and a detailed grouping of enzyme function. Moreover, classification performance did not improve drastically, if we additionally used homologous sites to predict function. Conclusions For a large number of enzymatic functions, dissimilar sites evolved that catalyze the same reaction and it is the individual substrate that determines the arrangement of the catalytic site and its local environment. These substrate-specific requirements turn the comparison of catalytic residues into a weak classifier for the prediction of enzyme function.
Additional file 1 of Impact of home healthcare on end-of-life outcomes for people with dementia: a systematic review
Creators: name: Chen, Ping-Jen
name: Smits, Lisanne
name: Miranda, Rose
name: Liao, Jung-Yu
name: Petersen, Irene
name: Van den Block, Lieve
name: Sampson, Elizabeth L.
Publisher: name: figshare
Year: 2022
Subjects: subject: Medicine
subject: Sociology
subject: FOS: Sociology
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Science Policy

description: Additional file 1: Supplementary file. Search strategy and terms in electronic databases.
Generating sets for coordinate rings of character varieties
Creators: name: Sikora, Adam S.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Algebraic Geometry (math.AG)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: 14D20, 14L30, 20C15

description: We find finite, reasonably small, generator sets of the coordinate rings of G-character varieties of finitely generated groups for all classical groups G. This result together with the method of Grobner basis gives an algorithm for describing character varieties by explicit polynomial equations. Additionally, we describe finite sets of generators of the fields of rational functions on G-character varieties for all exceptional algebraic groups G.
description: to appear in Journal of Pure and Applied Algebra, 18 pages, no figures
Magnetooptical study of Zeeman effect in Mn modulation-doped InAs/InGaAs/InAlAs quantum well structures
Creators: name: Terent'ev, Ya. V.
name: Danilov, Sergey
name: Plank, Helene
name: Loher, Josef
name: Schuh, Dieter
name: Bougeard, Dominique
name: Weiss, Dieter
name: Durney, M. V.
name: Tarasenko, Sergey
name: Rozhansky, I. V.
name: Ivanov, S. V.
name: Yakovlev, D. R.
name: Ganichev, Sergey
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: Quantum wells, magnetic fields, polarization, photoluminescence, Zeemann effect
subject: 530 Physik

description: We report on a magneto-photoluminescence (PL) study of Zeeman effect in Mn modulation-doped InAs/InGaAs/InAlAs quantum wells (QW). Two PL lines corresponding to the radiative recombination of photoelectrons with free and bound-on-Mn holes have been observed. In the presence of a magnetic field applied in the Faraday geometry, both lines split into two circularly polarized components. While temperature and magnetic field dependence of the splitting are well described by the Brillouin function, providing an evidence for exchange interaction with spin polarized manganese ions, the value of the splitting exceeds by two orders of magnitude the value of the giant Zeeman splitting estimated for the average Mn density in QW obtained by the secondary ion mass spectroscopy.
Building believable robots : an exploration of how to make simple robots look, move, and feel right
Creators: name: Bucci, Paul
Publisher: name: University of British Columbia
Year: 2017

description: Humans have an amazing ability to see a 'spark of life' in almost anything that moves. There is a natural urge to imbue objects with agency. It's easy to imagine a child pretending that a toy is alive. Adults do it, too, even when presented with evidence to the contrary. Leveraging this instinct is key to building believable robots, i.e. robots that act, look, and feel like they are social agents with personalities, motives, and emotions. Although it is relatively easy to initiate a feeling of agency, it is difficult to control, consistently produce, and maintain an emotional connection with a robot. Designing a believable interaction requires balancing form, function and context: you have to get the story right. In this thesis, we discuss (1) strategies for designing the bodies and behaviours of simple robot pets; (2) how these robots can communicate emotion; (3) and how people develop narratives that imbue the robots with agency. For (1), we developed a series of four robot design systems to create and rapidly iterate on robot form factors, as well as a tools for improvising and refining expressive robot behaviours. For (2), we ran three studies wherein participants rated robot behaviours in terms of arousal and valence under different display conditions. For (3), we ran a study wherein expert performers improvised emotional 'stories' with the robots; also one of the studies in (2) included soliciting narratives for the robot and its behaviours.
$n$-angulated categories
Creators: name: Geiss, Christof
name: Keller, Bernhard
name: Oppermann, Steffen
Publisher: name: arXiv
Year: 2010
Subjects: subject: K-Theory and Homology (math.KT)
subject: Rings and Algebras (math.RA)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: 18E30

description: We define $n$-angulated categories by modifying the axioms of triangulated categories in a natural way. We show that Heller's parametrization of pre-triangulations extends to pre-$n$-angulations. We obtain a large class of examples of $n$-angulated categories by considering $(n-2)$-cluster tilting subcategories of triangulated categories which are stable under the $(n-2)$nd power of the suspension functor. As an application, we show how $n$-angulated Calabi-Yau categories yield triangulated Calabi-Yau categories of higher Calabi-Yau dimension. Finally, we sketch a link to algebraic geometry and string theory.
description: notation in axiom F2 clarified, 16 pages; v3: new section 5.5, minor corrections, to appear in Crelle's Journal; v4: published version
Expression of the Foraging Gene Is Associated with Age Polyethism, Not Task Preference, in the Ant Cardiocondyla obscurior
Creators: name: Oettler, Jan
name: Nachtigal, Anna-Lena
name: Schrader, Lukas
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: 570 Biowissenschaften, Biologie
subject: 590 Tiere (Zoologie)

description: One of the fundamental principles of social organization, age polyethism, describes behavioral maturation of workers leading to switches in task preference. Here we present a system that allows for studying division of labor (DOL) by taking advantage of the relative short life of Cardiocondyla obscurior workers and thereby the pace of behavioral transitions. By challenging same-age young and older age cohorts to de novo establish DOL into nurse and foraging tasks and by forcing nurses to precociously become foragers and vice versa we studied expression patterns of one of the best known candidates for social insect worker behavior, the foraging gene. Contrary to our expectations we found that foraging gene expression correlates with age, but not with the task foraging per se. This suggests that this nutrition-related gene, and the pathways it is embedded in, correlates with physiological changes over time and potentially primes, but not determines task preference of individual workers.
Substantial biases in ultra-short read data sets from high-throughput DNA sequencing.
Creators: name: Dohm, Juliane C.
name: Lottaz, Claudio
name: Borodina, Tatiana
name: Himmelbauer, Heinz
Publisher: name: Universität Regensburg
Year: 2008
Subjects: subject: "Base Composition", "Beta vulgaris", "DNA", "Helicobacter", "Sequence Analysis, DNA", "Sequence Deletion", "Software"
subject: 004 Informatik
subject: 610 Medizin

description: Novel sequencing technologies permit the rapid production of large sequence data sets. These technologies are likely to revolutionize genetics and biomedical research, but a thorough characterization of the ultra-short read output is necessary. We generated and analyzed two Illumina 1G ultra-short read data sets, i.e. 2.8 million 27mer reads from a Beta vulgaris genomic clone and 12.3 million 36mers from the Helicobacter acinonychis genome. We found that error rates range from 0.3% at the beginning of reads to 3.8% at the end of reads. Wrong base calls are frequently preceded by base G. Base substitution error frequencies vary by 10- to 11-fold, with A > C transversion being among the most frequent and C > G transversions among the least frequent substitution errors. Insertions and deletions of single bases occur at very low rates. When simulating re-sequencing we found a 20-fold sequencing coverage to be sufficient to compensate errors by correct reads. The read coverage of the sequenced regions is biased; the highest read density was found in intervals with elevated GC content. High Solexa quality scores are over-optimistic and low scores underestimate the data quality. Our results show different types of biases and ways to detect them. Such biases have implications on the use and interpretation of Solexa data, for de novo sequencing, re-sequencing, the identification of single nucleotide polymorphisms and DNA methylation sites, as well as for transcriptome analysis.
High-fat diet prevents adaptive peripartum-associated adrenal gland plasticity and anxiolysis
Creators: name: Slattery, David A.
name: Perani, Clara Valentina
name: Neumann, Inga D.
name: Reber, Stefan Oskar
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: 590 Tiere (Zoologie)

description: Maternal obesity is associated with lower basal plasma cortisol levels and increased risk of postpartum psychiatric disorders. Given that both obesity and the peripartum period are characterized by an imbalance between adrenocorticotropic hormone (ACTH) and cortisol, we hypothesized that the adrenal glands undergo peripartum-associated plasticity and that such changes would be prevented by a high-fat diet (HFD). Here, we demonstrate substantial peripartum adrenal gland plasticity in the pathways involved in cholesterol supply for steroidogenesis in female rats. In detail, the receptors involved in plasma lipid uptake, low density lipoprotein (LDL) receptor (LDLR) and scavenger receptor class B type 1 (SRB1), are elevated, intra-adrenal cholesterol stores are depleted, and a key enzyme in de novo cholesterol synthesis, hydroxymethylglutaryl coenzyme A reductase (HMGCR), is downregulated; particularly at mid-lactation. HFD prevented the lactation-associated anxiolysis, basal hypercorticism, and exaggerated the corticosterone response to ACTH. Moreover, we show that HFD prevented the downregulation of adrenal cholesterol stores and HMGCR expression, and LDLR upregulation at mid-lactation. These findings show that the adrenal gland is an important regulator of peripartum-associated HPA axis plasticity and that HFD has maladaptive consequences for the mother, partly by preventing these neuroendocrine and also behavioural changes.
Additional file 2 of Microbiomes of air dust collected during the ground-based closed bioregenerative life support experiment "Lunar Palace 365"
Creators: name: Yang, Jianlou
name: Fu, Yuming
name: Liu, Hong
Publisher: name: figshare
Year: 2022
Subjects: subject: Microbiology
subject: FOS: Biological sciences

description: Additional file 2: Figure S1. (a) Comparison of microbial composition in different environments, according to SVM analysis. (b) Relative abundance (%) of the major genera present in the fungal microbial communities. LP: Lunar Palace 1; ISS: International Space Station. IP: indoor with plants. CO: classroom outdoor. CR: university classroom. Figure S2. Significant differences in richness diversity estimates of the microbial communities between the two crews. Figure S3. Relative sequence abundance, based on amplicon sequencing, of bacterial genera associated with G1 and G2. Figure S4. Relative sequence abundance, based on metagenome sequencing, of bacterial phyla (a) and genera (b) associated with G1 and G2. Figure S5. Comparison of community diversity among the different occupant groups and different sampling locations. (a) Comparison of community diversity among the different occupant groups in the CC. (b) Comparison of community diversity among the different occupant groups in the PC. (c) Comparison of community diversity among the different occupant groups in the SC. (d) Comparison of community diversity among the different sampling sites during the G1 group. (e) Comparison of community diversity among the different sampling sites during the G2 group. CC, comprehensive cabin; PC, plant cabin; SC, solid waste treatment cabin. Figure S6. Microbial functional diversity estimates for the two shifts. (a) Functional diversity between the two crew groups (no significant difference). (b) Functional redundancy index. (c) Functional diversity analysis based on metagenomics between the two crew groups. Figure S7. Correlation network analysis between ARGs and the airborne microbiome (P 0.4). Grey lines between the nodes indicate positive connections between the genera, while red lines indicate negative correlations.
Electromagnetic Oscillations in a Spherical Conducting Cavity with Dielectric Layers. Application to Linear Accelerators
Creators: name: Żakowicz, Władysław
name: Skorupski, Andrzej A.
name: Infeld, Eryk
Publisher: name: arXiv
Year: 2011
Subjects: subject: Accelerator Physics (physics.acc-ph)
subject: FOS: Physical sciences

description: We present an analysis of electromagnetic oscillations in a spherical conducting cavity filled concentrically with either dielectric or vacuum layers. The fields are given analytically, and the resonant frequency is determined numerically. An important special case of a spherical conducting cavity with a smaller dielectric sphere at its center is treated in more detail. By numerically integrating the equations of motion we demonstrate that the transverse electric oscillations in such cavity can be used to accelerate strongly relativistic electrons. The electron's trajectory is assumed to be nearly tangential to the dielectric sphere. We demonstrate that the interaction of such electrons with the oscillating magnetic field deflects their trajectory from a straight line only slightly. The Q factor of such a resonator only depends on losses in the dielectric. For existing ultra low loss dielectrics, Q can be three orders of magnitude better than obtained in existing cylindrical cavities.
description: Extended version with one new section, modified title and new abstract, 10 pages, 13 figures
Superconductivity near Pomeranchuk instabilities in the spin channel
Creators: name: Barci, Daniel G.
name: Bonfim, Paulo S. A.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study the competition between a Pomeranchuk instability in the spin channel with angular momentum $\ell=1$ and an attractive interaction, favoring Cooper-pair formation. We found that the superconducting gap strongly suppresses the phase space for the Pomeranchuk instability. We computed a mean-field phase diagram displaying a first order transition between two superconductor phases with different symmetries: p-wave (with spontaneously generated spin-orbit interaction) and s-wave for greater values of the coupling constant. Moreover, we have looked for a possible modulated superconducting phase. We have found that this phase appears only as a meta-stable state in the strong coupling regime.
description: 12 pages, 2 figures, paper greatly improved, intra-band interactions added, phase diagram (Fig. 1) changed. To appear in MPLB
Additional file 1 of The impact of improving haemophilia A management within the Spanish National Healthcare System: a social return on investment analysis
Creators: name: Soto, Inmaculada
name: Mateo, José
name: García-Diego, Daniel-Aníbal
name: Gil, Beatriz
name: Ruiz-Beato, Elena
name: Ivanova, Yoana
name: Martín Lorenzo, Teresa
name: Maravilla-Herrera, Paulina
name: Hidalgo-Vega, Álvaro
name: Merino, María
Publisher: name: figshare
Year: 2022
Subjects: Space Science
Medicine
Science Policy

description: Additional file 1.
Ultimate quantum bounds on mass measurements with a nano-mechanical oscillator
Creators: name: Braun, Daniel
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Nano-mechanical resonators have a large potential as sensors of very small adsorbed masses, down to the atomic level and beyond. Here I establish the fundamental lower bound on the mass that can be measured with a nano-mechanical oscillator in a given quantum state based on the quantum Cramér--Rao bound, limited only by the laws of quantum mechanics, and identify the quantum states which will allow the largest sensitivity for a given maximum energy.
description: Corrected a mistake in the formula for coherent states. Fig.1 and some numerical values changed
Characterization of Dnmt1 Binding and DNA Methylation on Nucleosomes and Nucleosomal Arrays
Creators: name: Längst, Gernot
name: Schrader, Anna
name: Gross, Thomas
name: Thalhammer, Verena
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: 570 Biowissenschaften, Biologie

description: The packaging of DNA into nucleosomes and the organisation into higher order structures of chromatin limits the access of sequence specific DNA binding factors to DNA. In cells, DNA methylation is preferentially occuring in the linker region of nucleosomes, suggesting a structural impact of chromatin on DNA methylation. These observations raise the question whether DNA methyltransferases are capable to recognize the nucleosomal substrates and to modify the packaged DNA. Here, we performed a detailed analysis of nucleosome binding and nucleosomal DNA methylation by the maintenance DNA methyltransferase Dnmt1. Our binding studies show that Dnmt1 has a DNA length sensing activity, binding cooperatively to DNA, and requiring a minimal DNA length of 20 bp. Dnmt1 needs linker DNA to bind to nucleosomes and most efficiently recognizes nucleosomes with symmetric DNA linkers. Footprinting experiments reveal that Dnmt1 binds to both DNA linkers exiting the nucleosome core. The binding pattern correlates with the efficient methylation of DNA linkers. However, the enzyme lacks the ability to methylate nucleosomal CpG sites on mononucleosomes and nucleosomal arrays, unless chromatin remodeling enzymes create a dynamic chromatin state. In addition, our results show that Dnmt1 functionally interacts with specific chromatin remodeling enzymes to enable complete methylation of hemi-methylated DNA in chromatin.
Cyclotron-resonance-assisted photcurrents in surface states of a three-dimensional topological insulator based on a strained high-mobility HgTe film
Creators: name: Dantscher, Kathrin-Maria
name: Kozlov, D. A.
name: Olbrich, Peter
name: Zoth, Christina
name: Faltermeier, Philipp
name: Lindner, M.
name: Budkin, G. V.
name: Tarasenko, Sergey
name: Belkov, Vassilij
name: Kvon, Z. D.
name: Mikhailov, N. N.
name: Dvoretsky, S. A.
name: Weiss, Dieter
name: Jenichen, B.
name: Ganichev, Sergey
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: 530 Physik
subject: 73.21.Fg, 72.25.Fe, 78.67.De, 73.63.Hs

description: We report on the observation of cyclotron-resonance-induced photocurrents, excited by continuous wave terahertz radiation, in a three-dimensional topological insulator (TI) based on an 80-nm strained HgTe film. The analysis of the photocurrent formation is supported by complementary measurements of magnetotransport and radiation transmission. We demonstrate that the photocurrent is generated in the topologically protected surface states. Studying the resonance response in a gated sample, we examined the behavior of the photocurrent, which enables us to extract the mobility and the cyclotron mass as a function of the Fermi energy. For high gate voltages, we also detected cyclotron resonance (CR) of bulk carriers, with a mass about two times larger than that obtained for the surface states. The origin of the CR-assisted photocurrent is discussed in terms of asymmetric scattering of TI surface carriers in the momentum space. Furthermore, we show that studying the photocurrent in gated samples provides a sensitive method to probe the cyclotron masses and the mobility of two-dimensional Dirac surface states, when the Fermi level lies in the bulk energy gap or even in the conduction band.
Behaviour in cultures and habitat requirements of species within the genera Loreleia and Rickenella (Agaricales)
Creators: name: Bresinsky, Andreas
name: Schötz, A.
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: eco-geogram; Rickenella; Loreleia; habitats; substrates; cultures; endangerment
subject: 580 Pflanzen (Botanik)

description: The term eco-geogram is introduced for surveying (in logical order) ecological and geographical data connected with fungal species. The database PILZOEK was established for that purpose. Eco-geograms are provided in this paper as an example for data retrieval from PILZOEK concerning the agarics Loreleia marchantiae, L. postii, Rickenella swartzii and R. fibula. The potential degree of endangerment is discussed in regard to habitat requirements. European species of Loreleia are not regarded to be endangered in Central Europe, although the risk to get threatened, because of low frequency of fruit body occurrence and quite a narrow substrate specialization, could be higher than in case of Rickenella fibula and R. swartzii. Cultures of Rickenella fibula, R. swartzii, Loreleia marchantiae (= Gerronema daamsii) and L. postii were investigated in regard to pigment accumulation, chlamydospore formation and some other characters.
Majorana tunneling entropy
Creators: name: Smirnov, Sergey
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: Majorana fermions, entropy, tunneling, quantum dot
subject: 530 Physik
subject: 74.45.+c
subject: 74.25.Bt
subject: 65.40.gd
subject: 74.78.Na

description: In thermodynamics a macroscopic state of a system results from a number of its microscopic states. This number is given by the exponent of the system's entropy $\exp(S)$. In non-interacting systems with discrete energy spectra, such as large scale quantum dots, $S$ as a function of the temperature has usually a plateau shape with integer values of $\exp(S)$ on these plateaus. Plateaus with non-integer values of $\exp(S)$ are fundamentally forbidden and would be thermodynamically infeasible. Here we investigate the entropy of a non-interacting quantum dot coupled via tunneling to normal metals with continuum spectra as well as to topological superconductors. We show that the entropy may have non-integer plateaus if the topological superconductors support weakly overlapping Majorana bound states. This brings a fundamental change in the thermodynamics of the quantum dot whose specific heat $c_V$ acquires low temperature Majorana peaks which should be absent according to the conventional thermodynamics. We also provide a fundamental thermodynamic understanding of the transport properties, such as the linear conductance. In general our results show that the thermodynamics of systems coupled to Majorana modes represents a fundamental physical interest with diverse applications depending on versatility of possible coupling mechanisms.
Periodic mean-field solutions and the spectra of discrete bosonic fields: Trace formula for Bose-Hubbard models
Creators: name: Engl, Thomas
name: Urbina, Juan Diego
name: Richter, Klaus
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: 530 Physik
subject: 05.45.Mt
subject: 03.65.Sq
subject: 03.65.Aa

description: We consider the many-body spectra of interacting bosonic quantum fields on a lattice in the semiclassical limit of large particle number N. We show that the many-body density of states can be expressed as a coherent sum over oscillating long-wavelength contributions given by periodic, nonperturbative solutions of the, typically nonlinear, wave equation of the classical (mean-field) limit. To this end, we construct the semiclassical approximation for both the smooth and oscillatory parts of the many-body density of states in terms of a trace formula starting from the exact path integral form of the propagator between many-body quadrature states. We therefore avoid the use of a complexified classical limit characteristic of the coherent state representation. While quantum effects such as vacuum fluctuations and gauge invariance are exactly accounted for, our semiclassical approach captures quantum interference and therefore is valid well beyond the Ehrenfest time where naive quantum-classical correspondence breaks down. Remarkably, due to a special feature of harmonic systems with incommensurable frequencies, our formulas are generically valid also in the free-field case of noninteracting bosons.
Additional file 1 of The mental health crisis of expectant women in the UK: effects of the COVID-19 pandemic on prenatal mental health, antenatal attachment and social support
Creators: name: Filippetti, Maria Laura
name: Clarke, Alasdair D. F.
name: Rigato, Silvia
Publisher: name: figshare
Year: 2022
Subjects: subject: Medicine
subject: Cell Biology
subject: Sociology
subject: FOS: Sociology
subject: Cancer
subject: Science Policy
subject: 111714 Mental Health
subject: FOS: Health sciences

description: Additional file 1.
Studies on the Coordination of Ribosomal Protein Assembly Events Involved in Prosessing and Stabiliz
Creators: name: Milkereit, Philipp
name: Griesenbeck, Joachim
name: Tschochner, Herbert
name: Ohmayer, Uli
name: Gil-Hernández, Álvaro
name: Sauert, Martina
name: Martín-Marcos, Pilar
name: Tamame, Mercedes
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: 610 Medizin

description: Cellular production of ribosomes involves the formation of highly defined interactions between ribosomal proteins (r-proteins) and ribosomal RNAs (rRNAs). Moreover in eukaryotic cells, efficient ribosome maturation requires the transient association of a large number of ribosome biogenesis factors (RBFs) with newly forming ribosomal subunits. Here, we investigated how r-protein assembly events in the large ribosomal subunit (LSU) rRNA domain II are coordinated with each other and with the association of RBFs in early LSU precursors of the yeast Saccharomyces cerevisiae. Specific effects on the pre-ribosomal association of RBFs could be observed in yeast mutants blocked in LSU rRNA domain II assembly. Moreover, formation of a cluster of r-proteins was identified as a downstream event in LSU rRNA domain II assembly. We analyzed in more detail the functional relevance of eukaryote specific bridges established by this r-protein cluster between LSU rRNA domain II and VI and discuss how they can support the stabilization and efficient processing of yeast early LSU precursor RNAs.
Traveling waves for a model of the Belousov-Zhabotinsky reaction
Creators: name: Trofimchuk, Elena
name: Pinto, Manuel
name: Trofimchuk, Sergei
Publisher: name: arXiv
Year: 2011
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 34K12, 35K57, 92D25

description: Following J.D. Murray, we consider a system of two differential equations that models traveling fronts in the Noyes-Field theory of the Belousov-Zhabotinsky (BZ) chemical reaction. We are also interested in the situation when the system incorporates a delay $h\geq 0$. As we show, the BZ system has a dual character: it is monostable when its key parameter $r \in (0,1]$ and it is bistable when $r >1$. For $h=0, r\not=1$, and for each admissible wave speed, we prove the uniqueness of monotone wavefronts. Next, a concept of regular super-solutions is introduced as a main tool for generating new comparison solutions for the BZ system. This allows to improve all previously known upper estimations for the minimal speed of propagation in the BZ system, independently whether it is monostable, bistable, delayed or not. Special attention is given to the critical case $r=1$ which to some extent resembles to the Zeldovich equation.
description: 23 pages, to appear in the Journal of Differential Equations
On the functor l^2
Creators: name: Heunen, Chris
Publisher: name: arXiv
Year: 2010
Subjects: subject: Category Theory (math.CT)
subject: Functional Analysis (math.FA)
subject: Quantum Physics (quant-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 46M99, 18A22, 46C07

description: We study the functor l^2 from the category of partial injections to the category of Hilbert spaces. The former category is finitely accessible, and its homsets are algebraic domains; the latter category has conditionally algebraic domains for homsets. The functor preserves daggers, monoidal structures, enrichment, and various (co)limits, but has no adjoints. Up to unitaries, its direct image consists precisely of the partial isometries, but its essential image consists of all continuous linear maps between Hilbert spaces.
description: 13 pages; updated Proposition 2.10
Nanofiltration and tight ultrafiltration membranes for drinking water treatment – system design and operation
Creators: name: Winter, Joerg
Publisher: name: University of British Columbia
Year: 2017

description: Nanofiltration (NF) and tight Ultrafiltration (UF) membranes represent a technology that is well suited for high quality drinking water production from source waters with high concentrations of natural organic matter (NOM) or other contaminants. However, the application of these membranes is limited, mainly because of the challenges related to fouling, concentration polarization (CP), system complexity and cost. The aim of the present study was to address these issues and to enable a more widespread application of this technology. Opportunities for simplifying NF and tight UF systems by, for instance, operation in dead-end mode, were explored. Experiments were conducted to evaluate the contribution of CP and fouling to the increase in resistance to permeate flow when filtering raw waters containing NOM. Continuous and periodic hydraulic measures to control CP and fouling were assessed. When filtering model raw waters containing humic substances, the increase in resistance to permeate flow was dominated by CP. When humic substances are effectively rejected and are present at high concentrations, CP becomes extensive, leading to a significant increase in the resistance to permeate flow by the formation of a cake/gel layer at the membrane surface. In the presence of calcium and particulate matter, the increase in resistance to permeate flow was dominated by fouling rather than CP. Filtration tests using periodic hydraulic measures to control fouling indicated that it was difficult to hydraulically remove the accumulated material once a foulant layer had been formed. Therefore, cross-flow operation, which reduces CP and prevents the formation of a foulant layer, is recommended. To optimize cross-flow operation, a framework was developed to compare the performance of NF membranes of different configurations (i.e. spiral wound and hollow fiber configurations) and geometries in terms of the permeate flux that can be sustained, and to optimize the operating set point of NF membranes with respect to system configuration, cross-flow velocity and operating flux with respect to cost. The results suggest that, despite higher manufacturing costs for hollow fiber NF, hollow fiber NF can be cost competitive to spiral wound NF. Because of operational advantages, the application of hollow fiber configurations is recommended.
Halocuprate(I) Zigzag Chain Structures with N-Methylated DABCO Cations – Bright Metal-Centered Luminescence and Thermally Activated Color Shifts
Creators: name: Maderlehner, Sebastian
name: Leitl, Markus J.
name: Yersin, Hartmut
name: Pfitzner, Arno
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: 540 Chemie

description: Two compounds 1,4-dimethyl-1,4-diazoniabicyclo[2.2.2]octane catena-tetra-μ-halo-dicuprate(I) with DABCOMe2 Cu2X4 (1: X = Br, 2: X = I) were synthesized by hydrothermal reaction of copper(I) halides with the corresponding 1,4-diazoniabicyclo[2.2.2]octane (DABCO) dihydrohalides in an acetonitrile/methanol mixture. Both compounds crystallize monoclinically, 1 with a = 9.169(4) Å, b = 10.916(6) Å, c = 15.349(6) Å, β = 93.93(2)°, V = 1533(1) Å3, Z = 4, space group P21/n (no. 14) and 2 with a = 15.826(9) Å, b = 9.476(5) Å, c = 22.90(2) Å, β = 90.56(5)°, V = 3434(5) Å3, Z = 8, space group P21 (no. 4), respectively (lattice constants refined from powder diffraction data measured at 293 K). The cations in both compounds are formed by in situ N-methylation of DABCOH22+ cations by methanol in a SN2 reaction. Both compounds contain an anionic copper(I) halide chain structure consisting of trans edge-sharing CuX4 tetrahedra. The chains are strongly kinked at every 2nd junction thus forming a zigzag structure. The shortest halide-halide distances are observed between the halide ions of adjacent tetrahedra which are approaching each other due to the kinking. This structure type shows a specific luminescence behavior. Under optical excitation, the compounds exhibit yellow (1) and green (2) emission with photoluminescence quantum yields of ΦPL = 52 and 4%, respectively, at ambient temperature. According to DFT and TDDFT calculations, the emission is assigned to be a phosphorescence essentially involving a metal centered transition between the HOMO consisting mainly of copper 3d and halide p orbitals and the LUMO consisting mainly of copper 4s and 4p orbitals. The temperature dependence of the emission spectra, decay times, and quantum yields has been investigated in detail, especially for 1. From the resulting trends it can be concluded that the emission for T ≤ 100 K stems from energetically lower lying copper halide segments. Such segments represent the structural motif of the halocuprate(I) chains. With increasing temperature energetically higher lying segments are populated which also emit, but open the pathway for thermally activated energy transfer to quenching defects.
description: Open Access Komponente aus der Allianzlizenz
Towards a Well-Founded Valuation of Managerial Fleibilities in IT Investment Projects - A Multidisciplinary Literature Review
Creators: name: Heinrich, Bernd
name: Müller, Marcel
name: Stoeckl, Sebastian
name: Zimmermann, Steffen
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: Real Options Analysis, Black-Scholes Model, Assumptions, Characteristics of IT Projects, Multidisciplinary Literature Review
subject: 330 Wirtschaft
subject: G11
subject: G13

description: In the IS literature standard financial option pricing models are predominantly used to value real options embedded in uncertain IT projects. Based on a multidisciplinary literature review, we discuss the assumptions implicit in the prevalent Black-Scholes model and argue for relaxed assumptions that better represent characteristics of uncertain IT projects. This is followed by a discussion of real option approaches from the fields of IS, Finance, and Economics in respect of their compliance with these relaxed assumptions. Findings are: (I) by relaxing the assumptions, the option value and project selection decisions are liable to change; (II) several approaches from Finance and Economics literature better comply with our relaxed assumptions compared to existing approaches in IS literature; (III) no existing real option approach complies with all relaxed assumptions. Adapting and enhancing approaches of other disciplines could be a push towards a well-founded valuation of real options embedded in IT projects.
The Cauchy problems for Einstein metrics and parallel spinors
Creators: name: Ammann, Bernd
name: Moroianu, Andrei
name: Moroianu, Sergiu
Publisher: name: arXiv
Year: 2011
Subjects: subject: Differential Geometry (math.DG)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 35A10, 35J47, 53C27, 53C44, 83C05

description: We show that in the analytic category, given a Riemannian metric $g$ on a hypersurface $M\subset \Z$ and a symmetric tensor $W$ on $M$, the metric $g$ can be locally extended to a Riemannian Einstein metric on $Z$ with second fundamental form $W$, provided that $g$ and $W$ satisfy the constraints on $M$ imposed by the contracted Codazzi equations. We use this fact to study the Cauchy problem for metrics with parallel spinors in the real analytic category and give an affirmative answer to a question raised in Bär, Gauduchon, Moroianu (2005). We also answer negatively the corresponding questions in the smooth category.
description: 28 pages; final version
Additional file 1 of Perceptions of oncology as a career choice among the early career doctors in Pakistan
Creators: name: Aemaz Ur Rehman, Muhammad
name: Farooq, Hareem
name: Ebaad Ur Rehman, Muhammad
name: Ali, Muhammad Mohsin
name: Zafar, Amjad
name: Khokhar, Muhammad Abbas
Publisher: name: figshare
Year: 2022
Subjects: subject: Medicine
subject: Biotechnology
subject: Sociology
subject: FOS: Sociology
subject: Cancer
subject: Science Policy
subject: 111714 Mental Health
subject: FOS: Health sciences

description: Additional file 1. Binary Logistic Regression of Factors Influencing the Preference of Oncology as a Career.
De-quantisation of the Quantum Fourier Transform
Creators: name: Abbott, Alastair A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The quantum Fourier transform (QFT) plays an important role in many known quantum algorithms such as Shor's algorithm for prime factorisation. In this paper we show that the QFT algorithm can, on a restricted set of input states, be de-quantised into a classical algorithm which is both more efficient and simpler than the quantum algorithm. By working directly with the algorithm instead of the circuit, we develop a simple classical version of the quantum basis-state algorithm. We formulate conditions for a separable state to remain separable after the QFT is performed, and use these conditions to extend the de-quantised algorithm to work on all such states without loss of efficiency. Our technique highlights the linearity of quantum mechanics as the fundamental feature accounting for the difference between quantum and de-quantised algorithms, and that it is this linearity which makes the QFT such a useful tool in quantum computation.
description: 14 pages. Belatedly updated to published version
The Effective Field Theory of Multifield Inflation
Creators: name: Senatore, Leonardo
name: Zaldarriaga, Matias
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We generalize the Effective Field Theory of Inflation to include additional light scalar degrees of freedom that are in their vacuum at the time the modes of interest are crossing the horizon. In order to make the scalars light in a natural way we consider the case where they are the Goldstone bosons of a global symmetry group or are partially protected by an approximate supersymmetry. We write the most general Lagrangian that couples the scalar mode associated to the breaking of time translation during inflation to the additional light scalar fields. This Lagrangian is constrained by diffeomorphism invariance and the additional symmetries that keep the new scalars light. This Lagrangian describes the fluctuations around the time of horizon crossing and it is supplemented with a general parameterization describing how the additional fluctuating fields can affect cosmological perturbations. We find that multifield inflation can reproduce the non-Gaussianities that can be generated in single field inflation but can also give rise to new kinds of non-Gaussianities. We find several new three-point function shapes. We show that in multifield inflation it is possible to naturally suppress the three-point function making the four-point function the leading source of detectable non-Gaussianities. We find that under certain circumstances, i.e. if specific shapes of non-Gaussianities are detected in the data, one could distinguish between single and multifield inflation and sometimes even among the various mechanisms that kept the additional fields light.
description: 62 pages, 1 figure; v2: JHEP published version, minor corrections, comments and references added