cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Pulling the straps of polygons
Creators: name: Gaiotto, Davide
name: Maldacena, Juan
name: Sever, Amit
name: Vieira, Pedro
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Using the Operator Product Expansion for Wilson loops we derive a simple formula giving the discontinuities of the two loop result in terms of the one loop answer. We also argue that the knowledge of these discontinuities should be enough to fix the full two loop answer, for a general number of sides. We work this out explicitly for the case of the hexagon and rederive the known result.
description: 42 pages, 4 figures
Formation and Evolution of Early-Type Galaxies: Spectro-Photometry from Cosmo-Chemo-Dynamical Simulations
Creators: name: Tantalo, Rosaria
name: Chinellato, Simonetta
name: Merlin, Emiliano
name: Piovan, Lorenzo
name: Chiosi, Cesare
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: One of the major challenges in modern astrophysics is to understand the origin and the evolution of galaxies, the bright, massive early type galaxies (ETGs) in particular. Therefore, these galaxies are likely to be good probes of galaxy evolution, star formation and, metal enrichment in the early Universe. In this context it is very important to set up a diagnostic tool able to combine results from chemo-dynamical N-Body-TSPH (NB-TSPH) simulations of ETGs with those of spectro-photometric population synthesis and evolution so that all key properties of galaxies can be investigated. The main goal of this paper is to provide a preliminary validation of the software package before applying it to the analysis of observational data. The galaxy models in use where calculated by the Padova group in two different cosmological scenarios: the SCDM, and the Lambda CDM. For these models, we recover their spectro-photometric evolution through the entire history of the Universe. We computed magnitudes and colors and their evolution with the redshift along with the evolutionary and cosmological corrections for the model galaxies at our disposal, and compared them with data for ETGs taken from the COSMOS and the GOODS databases. Starting from the dynamical simulations and photometric models at our disposal, we created synthetic images from which we derived the structural and morphological parameters. The theoretical results are compared with observational data of ETGs selected form the SDSS database. The simulated colors for the different cosmological scenarios follow the general trend shown by galaxies of the COSMOS and GOODS. Within the redshift range considered, all the simulated colors reproduce the observational data quite well.
description: 28 pages, 28 figures, accepted for pubblication by A&A
Gottes weisser Mantelsaum - Wollishofer Blog
Creators: name: Brändli, Sebastian
Publisher: name: Zentralbibliothek Zürich
Year: 2021
Subjects: subject: 800 Literatur und Rhetorik
subject: Zürich-Wollishofen
subject: Alvares Keller, Walter
subject: Roman

description: Ein Blog zu Geschichte und Quartierleben des Zürcher Stadtquartiers Wollishofen auf wollipedia.ch. Mit Texten von Sebastian Brändli (SB) und Ansichtskarten aus der Sammlung von Markus Zimmermann (MZ).
Atomic force microscopy at ambient and liquid conditions with stiff sensors and small amplitudes
Creators: name: Wutscher, Elisabeth
name: Giessibl, Franz J.
Publisher: name: Universität Regensburg
Year: 2011
Subjects: subject: atomic force microscopy; calcium compounds; diamond; force sensors; graphene; noise; Q-factor; quartz; vibrations
subject: 530 Physik
subject: 07.79.Lh
subject: 07.07.Df

description: We report on atomic force microscopy (AFM) in ambient and liquid environments with the qPlus sensor, a force sensor based on a quartz tuning fork with an all-electrical deflection measurement scheme. Small amplitudes, stiff sensors with bulk diamond tips and high Q values in air and liquid allow to obtain high resolution images. The noise sources in air and liquid are analyzed and compared for standard silicon cantilevers and qPlus sensors. First, epitaxial graphene was imaged in air, showing atomic steps with 3 Å height and ridges. As a second sample system, measurements on calcite (CaCO3) in liquids were performed in water and polyethylenglycol (PEG). We demonstrate high resolution images of steps in PEG on calcite and nanolithography processes, in particular with frequency-modulation AFM the controlled dissolution of calcite monolayers.
Evidence for Observation of Virtual Radio Cherenkov Fields
Creators: name: Bean, Alice
name: Ralston, John P.
name: Snow, James
Publisher: name: arXiv
Year: 2010
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present evidence for observation of virtual electromagnetic fields in the radio domain from experiment T926 at the Fermilab Meson Test Beam Facility. Relativistic protons with 120 GeV energy traversed a sealed electromagnetic cavity and were observed in the radio regime of 200MHz-GHz. Closely related to ordinary Cherenkov radiation, which we also measured, the virtual fields require no acceleration for their existence. The experiment is also the first observation of fields from hadronic showers, an independent and new confirmation of coherent radio emission from ultra-relativistic particles. Conditions of very low signal to noise were overcome by a novel and unbiased filtering strategy that exploits exhaustive studies of correlations in the noise backgrounds. Linear scaling of the signal region with the number of beam particles provides evidence of coherence. Extrapolation to measurement of the field of a single relativistic proton charge is consistent within errors. Our study also illustrates new data processing methods that may be applied broadly in conditions of extremely low signal to noise.
description: 35 pages, 17 figures
An efficient local coupled cluster method for accurate thermochemistry of large systems
Creators: name: Werner, Hans-Joachim
name: Schütz, Martin
Publisher: name: Universität Regensburg
Year: 2011
Subjects: subject: coupled cluster calculations; density functional theory; electron correlations; excited states; molecular configurations; perturbation theory; thermochemistry; wave functions
subject: 540 Chemie
subject: 31.15.bw
subject: 31.15.xp
subject: 31.15.V-
subject: 31.15.E-
subject: 33.15.Bh

description: An efficient local coupled cluster method with single and double excitation operators and perturbative treatment of triple excitations [DF-LCCSD(T)] is described. All required two-electron integrals are evaluated using density fitting approximations. These have a negligible effect on the accuracy but reduce the computational effort by 1–2 orders of magnitude, as compared to standard integral-direct methods. Excitations are restricted to local subsets of non-orthogonal virtual orbitals (domain approximation). Depending on distance criteria, the correlated electron pairs are classified into strong, close, weak, and very distant pairs. Only strong pairs, which typically account for more than 90% of the correlation energy, are optimized in the LCCSD treatment. The remaining close and weak pairs are approximated by LMP2 (local second-order Møller-Plesset perturbation theory); very distant pairs are neglected. It is demonstrated that the accuracy of this scheme can be significantly improved by including the close pair LMP2 amplitudes in the LCCSD equations, as well as in the perturbative treatment of the triples excitations. Using this ansatz for the wavefunction, the evaluation and transformation of the two-electron integrals scale cubically with molecular size. If local density fitting approximations are activated, this is reduced to linear scaling. The LCCSD iterations scale quadratically, but linear scaling can be achieved by neglecting some terms involving contractions of single excitations. The accuracy and efficiency of the method is systematically tested using various approximations, and calculations for molecules with up to 90 atoms and 2636 basis functions are presented.
Critical interfaces of the Ashkin-Teller model at the parafermionic point
Creators: name: Picco, Marco
name: Santachiara, Raoul
Publisher: name: arXiv
Year: 2010
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We present an extensive study of interfaces defined in the Z_4 spin lattice representation of the Ashkin-Teller (AT) model. In particular, we numerically compute the fractal dimensions of boundary and bulk interfaces at the Fateev-Zamolodchikov point. This point is a special point on the self-dual critical line of the AT model and it is described in the continuum limit by the Z_4 parafermionic theory. Extending on previous analytical and numerical studies [10,12], we point out the existence of three different values of fractal dimensions which characterize different kind of interfaces. We argue that this result may be related to the classification of primary operators of the parafermionic algebra. The scenario emerging from the studies presented here is expected to unveil general aspects of geometrical objects of critical AT model, and thus of c=1 critical theories in general.
description: 15 pages, 3 figures
Die Synthese verschiedener Carbonsäuren durch den Multienzymkomplex der Fettsäuresynthese aus Hefe und die Erklärung ihrer Bildung [ = Synthesis of various carboxylic acids by the fatty acid synthetase multienzyme complex of yeast and the explanation for their structure]
Creators: name: Sumper, Manfred
name: Oesterhelt, D.
name: Riepertinger, C.
name: Lynen, F.
Publisher: name: Universität Regensburg
Year: 1969
Subjects: subject: 540 Chemie
subject: 610 Medizin
subject: Carbon Isotopes
subject: Chromatography, Gas
subject: Coenzyme A/metabolism
subject: Fatty Acids/biosynthesis
subject: Glucosephosphate Dehydrogenase/metabolism
subject: Keto Acids/biosynthesis
subject: Kinetics
subject: Ligases/metabolism
subject: Malonates/metabolism
subject: Models, Chemical
subject: NAD/metabolism
subject: NADP/metabolism
subject: Palmitic Acids/biosynthesis
subject: Saccharomyces/enzymology
subject: Stearic Acids/biosynthesis

description: The purified multienzyme complex, fatty acid synthetase of yeast, produces palmityl-CoA and stearyl-CoA in equal amounts under standard conditions, with adequate NADPH, and a 1:2 ratio of acetyl-CoA and malonyl-CoA. Based on the known enzymatic properties of fatty acid synthetase a model which rationalizes the chain termination at the level of C16 and C18-acid is proposed. The model is based on two assumptions that are supported by experimental evidence: (a) the probability of any covalently enzyme-bound saturated acyl residue forming a product by transfer to CoA is determined by the relative velocities of the condensing and transferring reactions. (b) The growing alkan chain interacts with the enzyme protein only after a chain length of 13 carbon atoms has been attained; this interaction changes the relative velocities in favour of product formation by an energy increment of -0.9 kcal for each additional methylene group beyond the 13th. 3 To calculate the probability of product release at a particular chain length, an equation was derived from the model describing quantitatively the observed product distribution. 4 The formula suggests conditions under which either short acyl-CoA derivatives or exclusively stearyl-CoA can be produced. Synthesis under these conditions was examined experimentally and results indicated that the formula can be applied to a wide range of experimental conditions. 5 Because the condensation reaction in fatty acid synthesis is the rate limiting step under normal conditions, saturated acyl residues have the longest life-time as intermediates and consequently the highest probability of leaving the enzyme complex as an endproduct. The reduction reactions can be made rate limiting when the NADPH level drops. Under such circumstances β-ketoacyl-CoA's and α,β-unsaturated acyl-CoA's appear as endproducts. With NADH as electron donor the first reduction is slowed to such an extent that predominantly β-ketoacyl-CoA's derivatives are synthesized. 6 The possibility that the enzyme complex catalyses synthesis of short chain fatty acids and and β-ketoacids in vivo is discussed.
First Measurement of Hadronic Event Shapes in pp Collisions at sqrt(s)=7 TeV
Creators: name: CMS Collaboration
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Hadronic event shapes have been measured in proton-proton collisions at sqrt(s)=7 TeV, with a data sample collected with the CMS detector at the LHC. The sample corresponds to an integrated luminosity of 3.2 inverse picobarns. Event-shape distributions, corrected for detector response, are compared with five models of QCD multijet production.
How is attunement, disruption, and repair experienced by the therapist in an attachment-focused approach to psychotherapy?
Creators: name: Tavormina, Enza Maria Patrizia
Publisher: name: University of British Columbia
Year: 2017

description: This study explored the question: How is attunement, disruption and repair (ADR) experienced by the therapist in an attachment-focused approach to psychotherapy? The prevailing conception of ADR has emerged from a confluence of domains of inquiry: infant development research, psychotherapy, and affective neuroscience. However, it was not until recently that insights from these three areas of study converged. This convergence has created a flood of theoretical literature that conceptualizes ADR as a fundamental vehicle for change in the therapeutic relationship. However, two principal issues have been eluded: 1) there has been a lack of consensus on what constitutes attunement, disruption and repair and, 2) while ADR has been investigated extensively in infant development research and has been theorized to occur in the therapeutic relationship, there is a dearth of empirical demonstrations examining attunement, disrupton and repair as experienced by the therapist in the therapeutic process. The current research comprised a qualitative micro-analysis of the moment to moment shifts in the interactive process of ADR as experienced by the therapist. By investigating the question, “How is attunement, disruption and repair experienced by the therapist in an attachment-focused approach to psychotherapy?” the present qualitative study filled in a significant gap in the literature, contributed to our knowledge of the construct and the role of attunement, disruption and repair in the therapeutic process, informed existing theory on affect regulation and attachment repair, and informed the change process in therapy.
Wall-crossing from supersymmetric galaxies
Creators: name: Andriyash, Evgeny
name: Denef, Frederik
name: Jafferis, Daniel L.
name: Moore, Gregory W.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We give an elementary physical derivation of the Kontsevich-Soibelman wall crossing formula, valid for any theory with a 4d N=2 supergravity description. Our argument leads to a slight generalization of the formula, which relates monodromy to the BPS spectrum.
description: 15 pages
Efficient quantum dot single photon extraction into an optical fiber using a nanophotonic directional coupler
Creators: name: Davanço, M.
name: Rakher, M. T.
name: Wegscheider, Werner
name: Schuh, Dieter
name: Badolato, A.
name: Srinivasan, K.
Publisher: name: Universität Regensburg
Year: 2011
Subjects: subject: excitons; gallium arsenide; III-V semiconductors; indium compounds; nanophotonics; optical directional couplers; optical fibre couplers; photoluminescence; quantum dots
subject: 530 Physik
subject: 42.81.Qb

description: We demonstrate a spectrally broadband and efficient technique for collecting emission from a single InAs quantum dot directly into a standard single mode optical fiber. In this approach, an optical fiber taper waveguide is placed in contact with a suspended GaAs nanophotonic waveguide with embedded quantum dots, forming a broadband directional coupler with standard optical fiber input and output. Efficient photoluminescence collection over a wavelength range of tens of nanometers is demonstrated, and a maximum collection efficiency of 6% (corresponding single photon rate of 3.0 MHz) into a single mode optical fiber is estimated for a single quantum dot exciton.
The Oxygen Abundance in the Solar Neighborhood
Creators: name: Rodríguez, Mónica
name: Delgado-Inglada, Gloria
Publisher: name: arXiv
Year: 2011
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present a homogeneous analysis of the oxygen abundance in five H II regions and eight planetary nebulae (PNe) located at distances lower than 2 kpc and with available spectra of high quality. We find that both the collisionally excited lines and recombination lines imply that the PNe are overabundant in oxygen by about 0.2 dex. An explanation that reconciles the oxygen abundances derived with collisionally excited lines for H II regions and PNe with the values found for B-stars, the Sun, and the diffuse ISM requires the presence in H II regions of an organic refractory dust component that is not present in PNe. This dust component has already been invoked to explain the depletion of oxygen in molecular clouds and in the diffuse interstellar medium.
description: 5 pages, 1 figure, accepted for publication in ApJ Letters
Kerr-de Sitter Universe
Creators: name: Akcay, Sarp
name: Matzner, Richard
Publisher: name: arXiv
Year: 2010
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: It is now widely accepted that the universe as we understand it is accelerating in expansion and fits the de Sitter model rather well. As such, a realistic assumption of black holes must place them on a de Sitter background and not Minkowski as is typically done in General Relativity. The most astrophysically relevant black hole is the uncharged, rotating Kerr solution, a member of the more general Kerr-Newman metrics. A generalization of the rotating Kerr black hole to a solution of the Einstein's equation with a cosmological constant $Λ$ was discovered by Carter \cite{DWDW}. It is typically referred to as the Kerr-de Sitter spacetime. Here, we discuss the horizon structure of this spacetime and its dependence on $Λ$. We recall that in a $\La>0$ universe, the term `extremal black hole' refers to a black hole with angular momentum $J > M^2 $. We obtain explicit numerical results for the black hole's maximal spin value and get a distribution of admissible Kerr holes in the ($Λ$, spin) parameter space. We look at the conformal structure of the extended spacetime and the embedding of the 3-geometry of the spatial hypersurfaces. In analogy with Reissner-Nordström -de Sitter spacetime, in particular by considering the Kerr-de Sitter causal structure as a distortion of the Reissner-Nordström-de Sitter one, we show that spatial sections of the extended spacetime are 3-spheres containing 2-dimensional topologically spherical sections of the horizons of Kerr holes at the poles. Depending on how a $t=$ constant 3-space is defined these holes may be seen as black or white holes (four possible combinations).
description: 20 pages, 9 figures
One-dimentional magnonic crystal as a medium with magnetically tunable disorder on a periodical lattice
Creators: name: Ding, J.
name: Kostylev, M.
name: Adeyeye, A. O.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We show that periodic magnetic nanostructures (magnonic crystals) represent an ideal system for studying excitations on disordered periodical lattices because of the possibility of controlled variation of the degree of disorder by varying the applied magnetic field. Ferromagnetic resonance (FMR) data collected inside minor hysteresis loops for a periodic array of Permalloy nanowires of alternating width and magnetic force microscopy images of the array taken after running each of these loops were used to establish convincing evidence that there is a strong correlation between the type of FMR response and the degree of disorder of the magnetic ground state. We found two types of dynamic responses: anti-ferromagnetic (AFM) and ferromagnetic (FM), which represent collective spin wave modes or collective magnonic states. Depending on the history of sample magnetization either AFM or FM state is either the fundamental FMR mode or represents a state of a magnetic defect on the artificial crystal. A fundamental state can be transformed into a defect one and vice versa by controlled magnetization of the sample.
description: 4 pages, 3 figures, Letter paper, already submitted to PRL
Comment on "Anderson transition in disordered graphene"
Creators: name: Schleede, J.
name: Schubert, G.
name: Fehske, H.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We comment on a recent letter by Amini et al. (EPL 87, 37002 (2009)) concerning the existence of a mobility edge in disordered graphene.
description: 3 pages, 3 figures
Emergent Photons and Gravitons:The Problem of Vacuum Structure
Creators: name: Bjorken, J. D.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We discuss vacuum condensates associated with emergent QED and with torsion, as well as the possible role of the Kodama wave function in quantum cosmology.
description: Talk presented at the Fifth Meeting on CPT and Lorentz Symmetry, University of Indiana, June 28-July 2, 2010
Neue FeAsS-Käfigstrukturen aus [Cp+Fe(CO)2]2 (Cp+= C5Me4Et) und Realgar
Creators: name: Brunner, H.
name: Poll, L.
name: Wachter, Joachim
name: Nuber, B.
Publisher: name: Universität Regensburg
Year: 1994
Subjects: subject: 540 Chemie

description: The reaction of [Cp+Fe(CO)2]2 (Cp+= eta5-C5Me4Et) with equimolar amounts of As4S4 in boiling toluene gives Cp+2Fe2As2S2 (1) and Cp2+Fe2As2S3 (2). Both complexes form with two equivalents of Cr(CO)5THF the bisadducts Cp+2Fe2As2S2.2Cr(CO)5 (3) and Cp+2Fe2As2S3.2Cr(CO)5 (4), respectively. The Cr(CO)5 fragments are bound to the As atoms. X-ray diffraction analyses have been carried out for 1 and 4. The structure of 1 contains two coplanar eta2-AsS bridges which bisect the Fe-Fe vector and are parallel to the Cp+ ligands. Complex 1 is formulated as a 30e tripledecker complex for it contains an As-As distance (2.629(1) angstrom) very close to As-As bonding. The structure of 4 contains a Fe2As2S3 cage. The inorganic ligand is formally built up by two syn oriented AsS units which are bridged by a S atom. Such a view is supported by the conversion of 1 into 2 by reaction with a mild sulfur donator, e.g. As4S4.
Coordinated transmission for visible light communication systems
Creators: name: Ma, Hao
Publisher: name: University of British Columbia
Year: 2017

description: Visible light communication (VLC) is an emerging optical wireless communication technology that employs the light-emitting diode (LED) as the data transmitter. It has great potential to alleviate the strain on the radio-frequency (RF) spectrum in the indoor environment. The integration of VLC into indoor communication networks establishes optical attocells, responsible for the downlink traffic from the network to user terminals. These attocells could be easily deployed wherever LEDs are adopted for general illumination, including in electromagnetic interference sensitive areas like hospitals and airplanes. Although opaque bounds effectively contain light signals, VLC attocells would generally not operate free of interference. Illumination designers aim to have a uniform illumination at a certain height in the indoor environment, which mandates a rich overlap between the emissions of luminaires and results in unavoidable inter-attocell interference (IAI) from a communications perspective. This reality encourages us to propose the coordination of multiple VLC attocells (i.e., VLC-enabled LED luminaires) to turn the problem of overlap and thus interference into an advantage. In this thesis, we study how the coordination of VLC attocells can be employed to improve the user performance. Two coordinated VLC architectures, both of which utilize single-carrier transmission but differ at the coordination level, are investigated first. The analysis primarily focuses on the beamforming design subjected to the limited dynamic range of LED transmitters. The design of robust beamformers is also considered to combat the uncertainty of channel information at the transmitter. Finally, we propose a multi-carrier coordinated VLC architecture that uses power lines as the backbone network for the VLC front-end. Several subcarrier allocation schemes with varying degrees of tradeoff among hardware, computational complexity, and performance for meaningful variations of this hybrid system are proposed. The system designs developed throughout the thesis enable the collaboration among multiple LED transmitters in VLC systems, and our results indicate that these collaborative designs can significantly improve the performance of indoor VLC systems.
Excited States of the Nucleon in 2+1 Flavor QCD
Creators: name: Mahbub, M. S.
name: Kamleh, W.
name: Leinweber, D. B.
name: Moran, P. J.
name: Williams, A. G.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: Recent developments on the determination of the spin-1/2 spectrum of the nucleon in full QCD are presented. Our focus is on the PACS-CS 2+1 flavor configurations made available through the ILDG. Using correlation matrix techniques, in which a wide variety of gauge-invariant Gaussian-smeared fermion-propagator sources and sinks are considered, excited states are determined. We consider several correlation matrices of various sizes, each constructed with a different set of basis interpolators, in order to demonstrate the invariance of the eigenstates on the basis choice. Of particular interest is the approach to the elusive Roper resonance and we report preliminary results in full QCD.
description: 7 pages, 3 figures. Presented at the XXVIII International Symposium on Lattice Field Theory, Lattice2010, June 14-19, 2010, Villasimius, Italy
Anomalous antiferromagnetic coupling in Fe/Si/Fe structures with Co "dusting''
Creators: name: Gareev, R. R.
name: Buchmeier, M.
name: Kiessling, Matthias
name: Woltersdorf, Georg
name: Back, Christian H.
Publisher: name: Universität Regensburg
Year: 2011
Subjects: subject: antiferromagnetic materials; chemical interdiffusion; cobalt; Curie temperature; elemental semiconductors; iron; magnetic multilayers; magnetisation; metal-semiconductor-metal structures; silicon
subject: 530 Physik
subject: 75.70.Cn
subject: 68.35.Fx
subject: 75.30.Kz
subject: 75.60.Ej

description: We report on anomalous antiferromagnetic coupling in Fe/Si/Fe epitaxial structures with interfacial cobalt “dusting”. Antiferromagnetic coupling exceeds 75 μJ/m2 for a 2.0 nm-thick Si spacer and is still detectable for a 2.3 nm-thick spacer at room temperature. From room temperature to T**∼150K the magnetization follows Bloch's law and the coupling shows metallic-type behaviour; for lower temperatures the coupling is of insulating type. Below T*∼50K an additional magnetic signal arises and the coupling becomes metallic-type again. We relate the observed features to the formation of inter-diffused magnetic FeCo-silicides with a Curie temperature close to 50 K.
Water resources development in the Mullica River Basin - Part 1 - Biological evaluation of the Mullica River-Great Bay Estuary
Creators: name: No Name Supplied
Publisher: name: No Publisher Supplied
Year: 1972

description: This is the first volume of a three volume report on water resources development in the Mullica River Basin. In 1967, under the aegis of the Water Resources Research Institute at Rutgers University, New Brunswick, New Jersey, an interdisciplinary study was undertaken: the development potential of the water resources of the Mullica River Basin in New Jersey. The two groups involved were aquatic biologists and water resource engineers. Underlying this 570 square mile drainage basin are several aquifers. The one nearest to the surface has an average thickness of about 100 feet. For many years this aquifer has been considered as an important potential source of water for New Jersey. The objectives of the study were simply to determine the maximum possible shipment of water out of the basin that could take place without damage to the ecology of the river-bay system. Part I of the report presents a biological evaluation of the Mullica River - Great Bay Estuary.
Determinación de Micronutrientes en la Dieta de la Universidad de Navojoa, Mediante Espectrofotometría de Absorción Atómica
Creators: name: Solis Valladares, Victor Hugo
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 321001
subject: Clinical nutrition
classificationCode: 321002
subject: Food properties (incl. characteristics and health benefits)
classificationCode: 321004
subject: Nutritional science
classificationCode: 321005
subject: Public health nutrition

description: En esta investigación se presenta el resultado de la determinación cuantitativa de micronutrientes (cobre, zinc, hierro y manganeso) por el método de absorción atómica del menú (dieta lacto-ovovegetariana) de la Universidad de Navojoa durante el verano de 2015, para conocer si carece o cumple con los requerimientos suficientes de una dieta saludable, establecidos por la Normatividad Mexicana.
Spin-dependent Klein tunneling in graphene: Role of Rashba spin-orbit coupling
Creators: name: Liu, Ming-Hao
name: Bundesmann, Jan
name: Richter, Klaus
Publisher: name: Universität Regensburg
Year: 2012
Subjects: subject: 530 Physik
subject: 72 . 80 . Vp
subject: 72 . 25 . − b
subject: 73 . 23 . − b
subject: 73 . 40 . Gk

description: Within an effective Dirac theory the low-energy dispersions of monolayer graphene in the presence of Rashba spin-orbit coupling and spin-degenerate bilayer graphene are described by formally identical expressions. We explore implications of this correspondence for transport by choosing chiral tunneling through pn and pnp junctions as a concrete example. A real-space Green's function formalism based on a tight-binding model is adopted to perform the ballistic transport calculations, which cover and confirm previous theoretical results based on the Dirac theory. Chiral tunneling in monolayer graphene in the presence of Rashba coupling is shown to indeed behave like in bilayer graphene. Combined effects of a forbidden normal transmission and spin separation are observed within the single-band n to p transmission regime. The former comes from real-spin conservation, in analogy with pseudospin conservation in bilayer graphene, while the latter arises from the intrinsic spin-Hall mechanism of the Rashba coupling.
Tight-binding theory of the spin-orbit coupling in graphene
Creators: name: Konschuh, Sergej
name: Gmitra, Martin
name: Fabian, Jaroslav
Publisher: name: Universität Regensburg
Year: 2010
Subjects: subject: 530 Physik
subject: 31.15.ae, 71.15.Mb, 31.15.aj, 71.90.+q

description: The spin-orbit coupling in graphene induces spectral gaps at the high-symmetry points. The relevant gap at the Γ point is similar to the splitting of the p orbitals in the carbon atom, being roughly 8.5 meV. The splitting at the K point is orders of magnitude smaller. Earlier tight-binding theories indicated the value of this intrinsic gap of 1 μeV, based on the σ−π coupling. All-electron first-principles calculations give much higher values, between 25 and 50 μeV, due to the presence of the orbitals of the d symmetry in the Bloch states at K. A realistic multiband tight-binding model is presented to explain the effects the d orbitals play in the spin-orbit coupling at K. The π−σ coupling is found irrelevant to the value of the intrinsic spin-orbit-induced gap. On the other hand, the extrinsic spin-orbit coupling (of the Bychkov-Rashba type), appearing in the presence of a transverse electric field, is dominated by the π−σ hybridization, in agreement with previous theories. Tight-binding parameters are obtained by fitting to first-principles calculations, which also provide qualitative support for the model when considering the trends in the spin-orbit-induced gap in graphene under strain. Finally, an effective single-orbital next-nearest-neighbor hopping model accounting for the spin-orbit effects is derived.
Mechanism of Semaphorin-Plexin signaling in synaptic pattern formation in Caenorhabditis elegans
Creators: name: Chen, Xi
Publisher: name: University of British Columbia
Year: 2018

description: Fine motor coordination depends on the precise synaptic connection between individual motor neurons and muscles. Recent studies have revealed the roles of extracellular signals such as Wnt, Netrin, and Semaphorin in synapse specificity. Little is known about their intracellular mechanisms in synapse patterning. In C. elegans, DA class motor neurons form en passant synapses along their axon on the dorsal nerve cord. Each DA neuron innervates a unique and tiled segment of muscle field by restricting its synapse to a distinct subaxonal domain - a phenomenon we term synaptic tiling. SEMAs/Semaphorins and their receptor PLX-1/Plexin were previously shown to be critical for the tiled synaptic innervation pattern between two neighboring neurons DA8 and DA9. Recently, structural and biochemical studies have predicted that mammalian Plexin acts as a GTPase activating protein (GAP) for Rap small GTPases. In this study, among three rap genes in the C. elegans genome, rap-2 is found to be required for synaptic tiling and functions through cycling between GTP- and GDP-bound forms. The genetic study has illustrated that rap-2 acts downstream of plx-1 to regulate synaptic tiling, supporting that PLX-1 acts as a RapGAP to regulate the spatial activity of RAP-2. MIG-15 is identified as an effector of RAP-2 in synaptic tiling. mig-15 mutants display severe synaptic tiling defects due to the increased synapse number of DA8 and DA9. iii MIG-15 overexpression experiments demonstrated that MIG-15 controls both the length of synaptic domain and the number of synapses, while Plexin and RAP-2 define the length of the synaptic domain. PLX-1 overexpression experiments indicated that PLX-1 specifies synapse distribution via RAP-2 small GTPase and MIG-15 kinase. Overall, this study identified two novel components of Plexin signaling in the spatial regulation of synaptic pattern formation.
Theory of Spin Relaxation in Two-Electron Lateral Coupled Quantum Dots
Creators: name: Raith, Martin
name: Stano, Peter
name: Baruffa, Fabio
name: Fabian, Jaroslav
Publisher: name: Universität Regensburg
Year: 2012
Subjects: subject: 530 Physik

description: A global quantitative picture of the phonon-induced two-electron spin relaxation in GaAs double quantum dots is presented using highly accurate numerics. Wide regimes of interdot coupling, magnetic field magnitude and orientation, and detuning are explored in the presence of a nuclear bath. Mostimportant, the giant magnetic anisotropy of the singlet-triplet relaxation can be controlled by detuning switching the principal anisotropy axes: a protected state becomes unprotected upon detuning and vice versa. It is also established that nuclear spins can dominate spin relaxation for unpolarized triplets even at high magnetic fields, contrary to common belief.
Hamole - Wollishofer Blog
Creators: name: Brändli, Sebastian
Publisher: name: Zentralbibliothek Zürich
Year: 2021
Subjects: subject: 790 Freizetgestaltung, darstellende Künste, Sport
subject: Hamol AG (Zürich)
subject: Zürich-Wollishofen
subject: Sonnenbad
subject: Hautpflege

description: Ein Blog zu Geschichte und Quartierleben des Zürcher Stadtquartiers Wollishofen auf wollipedia.ch. Mit Texten von Sebastian Brändli (SB) und Ansichtskarten aus der Sammlung von Markus Zimmermann (MZ).
Vector boson pair production at the LHC
Creators: name: Campbell, John M.
name: Ellis, R. Keith
name: Williams, Ciaran
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We present phenomenological results for vector boson pair production at the LHC, obtained using the parton-level next-to-leading order program MCFM. We include the implementation of a new process in the code, pp -> γγ, and important updates to existing processes. We incorporate fragmentation contributions in order to allow for the experimental isolation of photons in γγ, Wγ, and Zγproduction and also account for gluon-gluon initial state contributions for all relevant processes. We present results for a variety of phenomenological scenarios, at the current operating energy of \sqrt{s} = 7 TeV and for the ultimate machine goal, \sqrt{s} = 14 TeV. We investigate the impact of our predictions on several important distributions that enter into searches for new physics at the LHC.
description: 35 pages, 14 figures
title: The social organization of nursing practice in the hospital setting and the influence on the development of conflicting working relationships between registered nurse peers
Creators: name: Rauman, Peggy A.
Publisher: name: Memorial University of Newfoundland
Year: 2020

description: The term conflicting working relationships (CWRs) is used in this research to represent working relationships between nurse peers that are non-collegial, uncaring, and non-supportive. These types of relationships have been reported in the research literature using many different labels including incivility, horizontal violence, and bullying and are known to be a source of job dissatisfaction, disengagement, and burnout. Despite efforts to limit the occurrences of CWRs between nurse peers, incidents of CWRs continue to occur. Using institutional ethnography, this research explored and made visible the relationship between the social organization of professional nursing practice in the hospital setting and the development of CWRs between Registered Nurse (RN) peers. Three aspects of the social organization of professional nursing practice, should nursing, double domination, and the big picture were revealed as creating disjunctures, frustrations, and tensions for nurses that were significant in the development of CWRs. The findings of this research further illuminate how conflict has become institutionalized and how there is a need for strong nursing leadership to advocate for workplace processes and contexts that support healthy and productive working relationships between nurse peers. The results of this study offer important insights into the ways CWRs between RN peers are influenced by the extra-level processes and relations of ruling that govern professional nursing practice. Through increased clarity of these factors, it is hoped that this research can be used to open a dialogue for leaders to discuss how nursing practice could be organized in a way that supports more collegial practices between RNs.
Iduronic acid: constituent of sulphated dolichyl phosphate oligosaccharides in halobacteria
Creators: name: Wieland, F.
name: Lechner, J.
name: Sumper, Manfred
Publisher: name: Universität Regensburg
Year: 1986
Subjects: subject: Iduronic acid Dolichyl oligosaccharide Glycoprotein biosynthesis Halobacteria
subject: 540 Chemie
subject: 610 Medizin

description: The occurrence of iduronic acid in the cell surface glycoprotein of halobacteria is described. This hexuronic acid is not only found in protein-linked oligosaccharides in halobacteria but does also exist in the corresponding dolichol-linked precursors. These findings were unexpected, as iduronic acid is a typical constituent of animal glycosaminoglycans, and its biosynthesis is so far known to occur by epimerization of a glucuronic acid residue within the completed carbohydrate chain linked to protein.
Rien ne va plus ! Faites vos jeux ! Retour sur une expérience de sensibilisation ludique à l'Open science dans les universités ultra-marines
Creators: name: Latour, Marie
name: Alarcon, Nicolas
Publisher: name: Zenodo
Year: 2022
Subjects: Données de la recherche
Formation
Doctorants
Jeu
Bande dessinée
Science ouverte

description: Rien ne va plus ! Faites vos jeux ! Et si pour impulser une véritable dynamique autour de l’Open Science et de l’Open Data au sein des établissements d’enseignement supérieur, on misait plutôt sur le divertissement que sur de longs discours ? Marie Latour et Nicolas Alarcon ont fait ce pari au sein de leurs établissements respectifs : l’Université de Guyane et l’Université de la Réunion. Ils ont proposé au sein de leurs bibliothèques des jeux de plateau et des bandes-dessinées pédagogiques pour familiariser un public de doctorants et de chercheurs. Retours sur cette pratique ludique pour promouvoir ces sujets sensibles et d’actualité.
Tensor Rank: Some Lower and Upper Bounds
Creators: name: Alexeev, Boris
name: Forbes, Michael
name: Tsimerman, Jacob
Publisher: name: arXiv
Year: 2011
Subjects: subject: Computational Complexity (cs.CC)
subject: FOS: Computer and information sciences
subject: F.2.1
subject: 68Q17 (Primary), 68W30 (Secondary)

description: The results of Strassen and Raz show that good enough tensor rank lower bounds have implications for algebraic circuit/formula lower bounds. We explore tensor rank lower and upper bounds, focusing on explicit tensors. For odd d, we construct field-independent explicit 0/1 tensors T:[n]^d->F with rank at least 2n^(floor(d/2))+n-Theta(d log n). This matches (over F_2) or improves (all other fields) known lower bounds for d=3 and improves (over any field) for odd d>3. We also explore a generalization of permutation matrices, which we denote permutation tensors. We show, by counting, that there exists an order-3 permutation tensor with super-linear rank. We also explore a natural class of permutation tensors, which we call group tensors. For any group G, we define the group tensor T_G^d:G^d->F, by T_G^d(g_1,...,g_d)=1 iff g_1 x ... x g_d=1_G. We give two upper bounds for the rank of these tensors. The first uses representation theory and works over large fields F, showing (among other things) that rank_F(T_G^d)<= |G|^(d/2). We also show that if this upper bound is tight, then super-linear tensor rank lower bounds would follow. The second upper bound uses interpolation and only works for abelian G, showing that over any field F that rank_F(T_G^d)<= O(|G|^(1+log d)log^(d-1)|G|). In either case, this shows that many permutation tensors have far from maximal rank, which is very different from the matrix case and thus eliminates many natural candidates for high tensor rank. We also explore monotone tensor rank. We give explicit 0/1 tensors T:[n]^d->F that have tensor rank at most dn but have monotone tensor rank exactly n^(d-1). This is a nearly optimal separation.
description: 27 pages
Superfluid state in the periodic Anderson model with attractive interactions
Creators: name: Koga, Akihisa
name: Werner, Philipp
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We investigate the periodic Anderson model with attractive interactions by means of dynamical mean-field theory (DMFT). Using a continuous-time quantum Monte Carlo impurity solver, we study the competition between the superfluid state and the paramagnetic Kondo insulating state, and determine the phase diagram. At the chemical potential-induced phase transition from the Kondo insulating state to the superfluid state, a low-energy peak characteristic of the superfluid state appears inside the hybridization gap. We also address the effect of the confining potential in optical lattice systems by means of real-space DMFT calculations.
description: 16 pages, 8 figures
Terroir and reputation : the economics of British Columbia wine industry in three essays.
Creators: name: Pankowska, Katarzyna
Publisher: name: University of British Columbia
Year: 2018

description: Terroir and collective reputations are two principal and interconnected elements believed to influence wine price and sales. In this dissertation, I examine the role of terroir (measurable features of the grape land) and collective reputation (eligibility for Vintners Quality Alliance, VQA) in determining the price, volume, and revenue of wine sales in British Columbia (BC). My research is highly relevant because this New World wine-producing region is currently altering its terroir-based geographical organization and sub-regional collective reputation, and plans to introduce new appellations and sub-appellations. My first chapter provides an empirical overview of the BC wine industry including market structure, market shares, and regulations. My first analytical chapter on terroir consists of using hedonic regression to connect wine prices and terroir. By matching grape and wine production at a micro level, I examine how agronomic characteristics of grape land affect the price of wine due to variation in grape quality. In this analysis, I make an extensive use of a detailed dataset consisting of vineyards' terroir characteristics. In my second analytical chapter of collective reputation, I use a three-stage endogenous dummy variable regression model to identify the average effect of VQA status on the average volume share, the average revenue share, and the average price of wine. I find somewhat limited evidence that vineyards' natural elements are important determinants of the price of BC wine. In my hedonic regression, the factors that seem to matter more are wine variety and brand. I also find that a relatively large number of wine brands represent VQA and that VQA certification positively influences the volume of sales for BC-made wines. My results also show that VQA certification has an insignificant impact on the average price and the average sales revenue of BC-made wines. Therefore, my results imply that VQA certification allows rent dissipation via over-certification. This over-certification allows arbitraging away of producers' rents.
Hydrogen Greenhouse Planets Beyond the Habitable Zone
Creators: name: Pierrehumbert, Raymond
name: Gaidos, Eric
Publisher: name: arXiv
Year: 2011
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We show that collision-induced absorption allows molecular hydrogen to act as an incondensible greenhouse gas, and that bars or tens of bars of primordial H2-He mixtures can maintain surface temperatures above the freezing point of water well beyond the "classical" habitable zone defined for CO2 greenhouse atmospheres. Using a 1-D radiative-convective model we find that 40 bars of pure H2 on a 3 Earth-mass planet can maintain a surface temperature of 280K out to 1.5AU from an early-type M dwarf star and 10 AU from a G-type star. Neglecting the effects of clouds and of gaseous absorbers besides H2, the flux at the surface would be sufficient for photosynthesis by cyanobacteria (in the G star case) or anoxygenic phototrophs (in the M star case). We argue that primordial atmospheres of one to several hundred bars of H2-He are possible, and use a model of hydrogen escape to show that such atmospheres are likely to persist further than 1.5 AU from M stars, and 2 AU from G stars, assuming these planets have protecting magnetic fields. We predict that the microlensing planet OGLE-05-390L could have retained a H2-He atmosphere and be habitable at ~2.6 AU from its host M star.
description: Accepted to Astrophysical Journal Letters