cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The metal enrichment of the intracluster medium in hierarchical galaxy formation models
Creators: name: Nagashima, Masahiro
name: Lacey, Cedric G.
name: Baugh, Carlton M.
name: Frenk, Carlos S.
name: Cole, Shaun
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We investigate the metal enrichment of the intracluster medium (ICM) in the framework of hierarchical models of galaxy formation. We calculate the formation and evolution of galaxies and clusters using a semi-analytical model which includes the effects of flows of gas and metals both into and out of galaxies. For the first time in a semi-analytical model, we calculate the production of both alpha and iron-peak elements based on theoretical models for the lifetimes and ejecta of type Ia and type II supernovae (SNe Ia and SNe II). It is essential to include the long lifetimes of the SNIa progenitors in order to correctly model the evolution of the iron-peak elements. We find that if all stars form with an IMF similar to that found in the solar neighbourhood, then the metallicities of O, Mg, Si and Fe in the ICM are predicted to be 2-3 times lower than observed values. In contrast, a model (also favoured on other grounds) in which stars formed in bursts triggered by galaxy mergers have a top-heavy IMF reproduces the observed ICM abundances of O, Mg, Si and Fe. The same model predicts ratios of ICM mass to total stellar luminosity in clusters which agree well with observations. According to our model, the bulk of the metals in clusters are produced by L* and brighter galaxies. [abridged]
description: 21 pages including 21 figures, accepted for publication in MNRAS
Field sweep rate dependence of the coercive field of single-molecule magnets: a classical approach with applications to the quantum regime
Creators: name: Wernsdorfer, W.
name: Murugesu, M.
name: Tasiopoulos, A. J.
name: Christou, G.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A method, based on the Neel-Brown model of thermally activated magnetization reversal of a magnetic single-domain particle, is proposed to study the field sweep rate dependence of the coercive field of single-molecule magnets (SMMs). The application to Mn12 and Mn84 SMMs allows the determination of the important parameters that characterize the magnetic properties: the energy barrier, the magnetic anisotropy constant, the spin, tau_0, and the crossover temperature from the classical to the quantum regime. The method may be particularly valuable for large SMMs that do not show quantum tunneling steps in the hysteresis loops.
description: 6 pages, 6 figures
Symmetries of field theories on the non-commutative plane
Creators: name: Horvathy, P. A.
name: Martina, L.
name: Stichel, P. C.
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: New developments on the symmetries of non-relativistic field theoretical models on the non commutative plane are reviewed. It is shown in particular that Galilean invariance strongly restricts the admissible interactions. Moreover, if a scalar field is coupled to a Chern - Simons gauge field, a geometrical phase emerges for vortex - like solutions, transformed by Galilei boosts.
description: Reference corrected. Talk presented by LM at the International Workshop Nonlinear Physics: Theory and Experiment III. Gallipoli, (Lecce, Italy) 2004. To appear in Theor. Math. Phys. Latex 9 pages
Die Genossenschaft als alternative Unternehmensform in einer sich transformierenden Sozialwirtschaft
Creators: name: Stockmayer, Franziska
Publisher: name: DWI-Jahrbuch – Diakoniewissenschaft in Forschung und Lehre
Year: 2023

description: DWI-Jahrbuch – Diakoniewissenschaft in Forschung und Lehre, Bd. 48: (2022/2023): Diakoniewissenschaft in Forschung und Lehre
The fast and the slow axonal transport: a unified approach based on cargo and molecular motors coupled dynamics
Creators: name: Cho, Alexandre Y. C.
name: Roque, Victor R. C. M.
name: Goldman, Carla
Publisher: name: arXiv
Year: 2020
Subjects: subject: Subcellular Processes (q-bio.SC)
subject: FOS: Biological sciences

description: The origins of the large differences observed to the rates with which the diverse particles are conveyed along axonal microtubules are still a matter of debate in the literature. There is evidence that certain neurodegenerative diseases may be triggered by disturbances to the related transport processes. Motivated by this, we employ a model to investigate the mobility properties of certain cargoes which dynamics are coupled with that of molecular motors on crowded microtubules. For certain initial and boundary conditions, we use the method of characteristics to resolve perturbatively the pair of equations of the Burgers type resulting from a mean-field approach to the original microscopic stochastic model. Extensions to the non-perturbative limits are explored numerically. In this context, we were able to figure out conditions under which cargos average velocities may differ up to orders of magnitude just by changing the number of motors on the considered track. We then discuss possibilities to connect these theoretical predictions with available experimental data about axon transport.
Towards a new approach to quantum gravity phenomenology
Creators: name: Corichi, Alejandro
name: Sudarsky, Daniel
Publisher: name: arXiv
Year: 2005
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The idea that quantum gravity manifestations would be associated with a violation of Lorentz invariance is very strongly bounded and faces serious theoretical challenges. This leads us to consider an alternative line of thought for such phenomenological search. We discuss the underlying viewpoint and briefly mention its possible connections with current theoretical ideas. We also outline the challenges that the experimental search of the effects would seem to entail.
description: 13 pages, no figures. Discussion added, same conclusions
Fifty Years of IMF Variation: The Intermediate-Mass Stars
Creators: name: Scalo, John
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: I track the history of star count estimates of the Milky Way field star and open cluster IMFs, concentrating on the neglected mass range from 1 to 15 M${_\odot}$. The prevalent belief in a universal IMF appears to be without basis for this mass range. Two recent estimates of the field star IMF using different methods and samples give values of the average logarithmic slope $Γ$ between -1.7 and -2.1 in the mass range 1.1 to 4 M${_\odot}$. Two older estimates between 2 and 15 M${_\odot}$ disagree severely; the field IMF in this range is essentially unknown from star counts. Variations in $Γ$ among open cluster IMFs in this mass range have not decreased despite numerous detailed studies, even for studies using homogeneous data and reduction procedures and including only clusters with a significant mass range. These cluster variations \textit{might} be due to the combined effects of sampling, systematic errors, stellar evolution uncertainties, dynamical evolution, and unresolved binaries. If so, then the cluster data are consistent with a universal IMF, but are also consistent with sizeable variations. The cluster data do not allow an estimate of an average IMF or $Γ$ because the average depends on the choice of weighting procedure and other effects. If the spread in cluster IMFs is in excess of the effects listed above, real IMF variations must occur that do not depend much on physical conditions explored so far. The complexity of the star formation process seen in observations and simulations suggests that large realization-to-realization differences might be expected, in which case an individual cluster IMF would be in part the product of evolutionary contingency in star formation, and the function of interest is the probability distribution of IMF parameters.
description: 18 pages, including 4 figures: invited talk presented at the conference on "IMF@50: The Stellar Initial Mass Function Fifty Years Later" held at Abbazia di Spineto, Siena, Italy, May 2004; to be published by Kluwer Academic Publishers, edited by E. Corbelli, F. Palla, and H. Zinnecker
Stärkung der Selbstbestimmung und Teilhabemöglichkeiten demenziell erkrankter Menschen
Creators: name: Lee, Jeonghyun
Publisher: name: DWI-Jahrbuch – Diakoniewissenschaft in Forschung und Lehre
Year: 2023

description: DWI-Jahrbuch – Diakoniewissenschaft in Forschung und Lehre, Bd. 48: (2022/2023): Diakoniewissenschaft in Forschung und Lehre
Efficient State Preparation for Quantum Amplitude Estimation
Creators: name: Vazquez, Almudena Carrera
name: Woerner, Stefan
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Quantum Amplitude Estimation (QAE) can achieve a quadratic speed-up for applications classically solved by Monte Carlo simulation. A key requirement to realize this advantage is efficient state preparation. If state preparation is too expensive, it can diminish the quantum advantage. Preparing arbitrary quantum states has exponential complexity with respect to the number of qubits, thus, is not applicable. Currently known efficient techniques require problems based on log-concave probability distributions, involve learning an unknown distribution from empirical data, or fully rely on quantum arithmetic. In this paper, we introduce an approach to simplify state preparation, together with a circuit optimization technique, both of which can help reduce the circuit complexity for QAE state preparation significantly. We demonstrate the introduced techniques for a numerical integration example on real quantum hardware, as well as for option pricing under the Heston model, i.e., based on a stochastic volatility process, using simulation.
description: 12 pages, 12 figures
Evidence for variability timescale dependent UV/X-ray delay in Seyfert 1 AGN NGC 7469
Creators: name: Pahari, Mayukh
name: McHardy, Ian M.
name: Vincentelli, Federico
name: Cackett, Edward M.
name: Peterson, Bradley M.
name: Goad, Michael R.
name: Gültekin, Kayhan
name: Horne, Keith
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Using a month-long X-ray lightcurve from ${\it RXTE}$/PCA and 1.5 month long UV continuum lightcurves from ${\it IUE}$ spectra in 1220$-$1970 $Å$, we performed a detailed time-lag study of the Seyfert 1 galaxy NGC 7469. Our cross-correlation analysis confirms previous results showing that the X-rays are delayed relative to the UV continuum at 1315 $Å$ by 3.49 $\pm$ 0.22 days which is possibly caused by either propagating fluctuation or variable comptonisation. However, if variations slower than 5 days are removed from the X-ray lightcurve, the UV variations then lag behind the X-rays variations by 0.37$\pm$0.14 day, consistent with reprocessing of the X-rays by a surrounding accretion disc. A very similar reverberation delay is observed between ${\it Swift}$/XRT X-ray and ${\it Swift}$/UVOT UVW2, U lightcurves. Continuum lightcurves extracted from the ${\it Swift}$/GRISM spectra show delays with respect to X-rays consistent with reverberation. Separating the UV continuum variations faster and slower than 5 days, the slow variations at 1825 $Å$ lag those at 1315 $Å$ by $0.29\pm0.06$ day, while the fast variations are coincident ($0.04\pm0.12$ day). The UV/optical continuum reverberation lag from ${\it IUE}$, ${\it Swift}$ and other optical telescopes at different wavelengths are consistent with the relationship: $τ\propto λ^{4/3}$, predicted for the standard accretion disc theory while the best-fit X-ray delay from ${\it RXTE}$ and ${\it Swift}$/XRT shows a negative X-ray offset of $\sim$0.38 days from the standard disc delay prediction.
description: 13 pages, 9 figures, 1 table, accepted for publication in MNRAS
Maximum elastic deformations of compact stars with exotic equations of state
Creators: name: Owen, Benjamin J.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: I make the first estimates of maximum elastic quadrupole deformations sustainable by alternatives to conventional neutron stars. Solid strange quark stars might sustain maximum ellipticities (dimensionless quadrupoles) up to a few times $10^{-4}$ rather than a few times $10^{-7}$ for conventional neutron stars, and hybrid quark-baryon or meson-condensate stars might sustain up to $10^{-5}$. Most of the difference is due to the shear modulus, which can be up to $10^{33}$ erg/cm$^3$ rather than $10^{30}$ erg/cm$^3$ in the inner crust of a conventional neutron star. Maximum solid strange star ellipticities are comparable to upper limits obtained for several known pulsars in a recent gravitational-wave search by LIGO. Maximum ellipticities of the more robust hybrid model will be detectable by LIGO at initial design sensitivity. A large shear modulus also strengthens the case for starquakes as an explanation for frequent pulsar glitches.
description: 4 pages, no figures; Introduction reworked, SGR1806-20 mentioned in Implications, minor changes elsewhere; final version as appearing in PRL
The early phases of Milky Way's chemical evolution
Creators: name: Prantzos, Nikos
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The earliest phases of the chemical evolution of our Galaxy are analysed in the light of the recent VLT results (concerning abundance patterns in the most metal-poor stars of the Galactic halo) and of stellar nucleosynthesis calculations. It is argued that: 1) the unexpected abundance patterns observed in Pop. II stars are not the imprints of an early generation of supermassive Pop. III stars; 2) among the various suggestions made to exlain the observed abundance patterns, nucleosynthesis in asymmetric supernova explosions appears most promising. In the latter case, an indirect correlation between asymmetry and metallicity is suggested by the data. Finally, the VLT data confirm two old ``puzzles'': the existence of primary N early in Galaxy's evolution (which constrains the mixing of protons with He-burning products in massive stars) and the absence of dispersion in abundance ratios, at least up to the Fe peak, in the early Galaxy (which bears on the timescales of homogeneisation of the interstellar medium, but also on yield variations among massive stars).
description: 10 pages, 4 figures, Review talk in Nuclei in the Cosmos VIII (Eds. L. Buchmann et al.) to appear in NuclPhys A
Determination of the escape velocity of the Milky Way using a proper motion selected halo sample
Creators: name: Koppelman, Helmer H.
name: Helmi, Amina
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The {\it Gaia} mission has provided the largest catalogue ever of sources with tangential velocity information. However, using this catalogue for dynamical studies is difficult because most of the stars lack line-of-sight velocity measurements. Recently, we presented a selection of $\sim 10^7$ halo stars with accurate distances that have been selected based on their photometry and proper motions. Using this sample, we model the tail of the velocity distribution with a power-law distribution, a commonly used approach first established by \cite{Leonard1990THESPEED}. For the first time ever we use tangential velocities measured accurately for an unprecedented number of halo stars to estimate the escape velocity. In the solar neighbourhood, we obtain a very precise estimate of the escape velocity which is $497^{+8}_{-8}~{\rm km/s}$. This estimate is most likely biased low, our best guess is by 10\%. As a result, the true escape velocity most likely is closer to $550~{\rm km/s}$. The escape velocity directly constrains the total mass of the Milky Way. To find the best fitting halo mass and concentration parameter we adjusted the dark (spherical NFW) halo of a realistic Milky Way potential while keeping the circular velocity at the solar radius fixed at $v_c(R_\odot) = 232.8~{\rm km/s}$. The resulting halo parameters are $M_{200}^{+10\%} = 1.11^{+0.08}_{-0.07} \cdot10^{12} ~{\rm M}_\odot$ and concentration parameter $c^{+10\%} = 11.8^{+0.3}_{-0.3}$, where we use the explicit notation to indicate that these have been corrected for the 10\% bias. The slope of the escape velocity with galactocentric distance is as expected in the inner Galaxy based on Milky Way models. Curiously, we find a disagreement beyond the solar radius which is likely an effect of a change in the shape of the velocity distribution and could be related to the presence of velocity clumps.
description: 14 pages, 13 figures, accepted for publication in A&A
Text S4 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts
Creators: name: LeKieffre, Charlotte
name: Spero, Howard J.
name: Fehrenbacher, Jennifer S.
name: Russell, Ann D.
name: Haojia Ren
name: Geslin, Emmanuelle
name: Meibom, Anders
Publisher: name: The Royal Society
Year: 2020
Subjects: subject: Microbiology
subject: FOS: Biological sciences
subject: Ecology
subject: 40308 Palaeontology (incl. Palynology)
subject: FOS: Earth and related environmental sciences

description: The symbiotic planktonic foraminifera Orbulina universa inhabits open ocean oligotrophic ecosystems where dissolved nutrients are scarce and often limit biological productivity. It has previously been proposed that O. universa meets its nitrogen (N) requirements by preying on zooplankton, and that its symbiotic dinoflagellates recycle metabolic ‘waste ammonium’ for their N pool. However, these conclusions were derived from bulk 15N-enrichment experiments and model calculations, and our understanding of N assimilation and exchange between the foraminifer host cell and its symbiotic dinoflagellates remains poorly constrained. Here, we present data from pulse-chase experiments with 13C-enriched inorganic carbon, 15N-nitrate and 15N-ammonium, as well as a 13C- and 15N- enriched heterotrophic food source, followed by TEM coupled to NanoSIMS isotopic imaging to visualize and quantify C and N assimilation and translocation in the symbiotic system. High levels of 15N-labelling were observed in the dinoflagellates and in foraminiferal organelles and cytoplasm after incubation with 15N-ammonium, indicating efficient ammonium assimilation. Only weak 15N-assimilation was observed after incubation with 15N-nitrate. Feeding foraminifers with 13C- and 15N-labelled food resulted in dinoflagellates that were labelled with 15N, thereby confirming the transfer of 15N-compounds from the digestive vacuoles of the foraminifer to the symbiotic dinoflagellates, likely through recycling of ammonium. These observations are important for N isotope-based paleoceanographic reconstructions, as they show that δ15N values recorded in the organic matrix in symbiotic species likely reflect ammonium recycling rather than alternative N sources, such as nitrates.
Spatial variations of low mass negative ions in Titan's upper atmosphere
Creators: name: Mihailescu, Teodora
name: Desai, Ravindra
name: Shebanits, Oleg
name: Haythornthwaite, Richard
name: Wellbrock, Anne
name: Coates, Andrew
name: Eastwood, Jonathan
name: Waite, J. Hunter
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Observations with Cassini's Electron Spectrometer discovered negative ions in Titan's ionosphere, at altitudes between 1400 and 950 km. Within the broad mass distribution extending up to several thousand amu, two distinct peaks were identified at 25.8-26.0 and 49.0-50.1 amu/q, corresponding to the carbon chain anions $CN^-$ and/or $C_2H^-$ for the first peak and $C_3N^-$ and/or $C_4H^-$ for the second peak. In this study we present the spatial distribution of these low mass negative ions from 28 Titan flybys with favourable observations between 26 October 2004 and 22 May 2012. We report a trend of lower densities on the night side and increased densities up to twice as high on the day side at small solar zenith angles. To further understand this trend, we compare the negative ion densities to the total electron density measured by Cassini's Langmuir Probe. We find the low mass negative ion density and the electron density to be proportional to each other on the dayside, but independent of each other on the night side. This indicates photochemical processes and is in agreement with the primary production route for the low mass negative ions being initiated by dissociative reactions with suprathermal electron populations produced by photoionisation. We also find the ratio of $CN^-/C_2H^-$ to $C_3N^-/C_4H^-$ highly constrained on the day-side, in agreement with this production channel, but notably displays large variations on the nightside.
description: 11 pages, 5 figures
Figure S1 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts
Creators: name: LeKieffre, Charlotte
name: Spero, Howard J.
name: Fehrenbacher, Jennifer S.
name: Russell, Ann D.
name: Haojia Ren
name: Geslin, Emmanuelle
name: Meibom, Anders
Publisher: name: The Royal Society
Year: 2020
Subjects: subject: Microbiology
subject: FOS: Biological sciences
subject: Ecology
subject: 40308 Palaeontology (incl. Palynology)
subject: FOS: Earth and related environmental sciences

description: The symbiotic planktonic foraminifera Orbulina universa inhabits open ocean oligotrophic ecosystems where dissolved nutrients are scarce and often limit biological productivity. It has previously been proposed that O. universa meets its nitrogen (N) requirements by preying on zooplankton, and that its symbiotic dinoflagellates recycle metabolic ‘waste ammonium’ for their N pool. However, these conclusions were derived from bulk 15N-enrichment experiments and model calculations, and our understanding of N assimilation and exchange between the foraminifer host cell and its symbiotic dinoflagellates remains poorly constrained. Here, we present data from pulse-chase experiments with 13C-enriched inorganic carbon, 15N-nitrate and 15N-ammonium, as well as a 13C- and 15N- enriched heterotrophic food source, followed by TEM coupled to NanoSIMS isotopic imaging to visualize and quantify C and N assimilation and translocation in the symbiotic system. High levels of 15N-labelling were observed in the dinoflagellates and in foraminiferal organelles and cytoplasm after incubation with 15N-ammonium, indicating efficient ammonium assimilation. Only weak 15N-assimilation was observed after incubation with 15N-nitrate. Feeding foraminifers with 13C- and 15N-labelled food resulted in dinoflagellates that were labelled with 15N, thereby confirming the transfer of 15N-compounds from the digestive vacuoles of the foraminifer to the symbiotic dinoflagellates, likely through recycling of ammonium. These observations are important for N isotope-based paleoceanographic reconstructions, as they show that δ15N values recorded in the organic matrix in symbiotic species likely reflect ammonium recycling rather than alternative N sources, such as nitrates.
Text S1 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts
Creators: name: LeKieffre, Charlotte
name: Spero, Howard J.
name: Fehrenbacher, Jennifer S.
name: Russell, Ann D.
name: Haojia Ren
name: Geslin, Emmanuelle
name: Meibom, Anders
Publisher: name: The Royal Society
Year: 2020
Subjects: subject: Microbiology
subject: FOS: Biological sciences
subject: Ecology
subject: 40308 Palaeontology (incl. Palynology)
subject: FOS: Earth and related environmental sciences

description: The symbiotic planktonic foraminifera Orbulina universa inhabits open ocean oligotrophic ecosystems where dissolved nutrients are scarce and often limit biological productivity. It has previously been proposed that O. universa meets its nitrogen (N) requirements by preying on zooplankton, and that its symbiotic dinoflagellates recycle metabolic ‘waste ammonium’ for their N pool. However, these conclusions were derived from bulk 15N-enrichment experiments and model calculations, and our understanding of N assimilation and exchange between the foraminifer host cell and its symbiotic dinoflagellates remains poorly constrained. Here, we present data from pulse-chase experiments with 13C-enriched inorganic carbon, 15N-nitrate and 15N-ammonium, as well as a 13C- and 15N- enriched heterotrophic food source, followed by TEM coupled to NanoSIMS isotopic imaging to visualize and quantify C and N assimilation and translocation in the symbiotic system. High levels of 15N-labelling were observed in the dinoflagellates and in foraminiferal organelles and cytoplasm after incubation with 15N-ammonium, indicating efficient ammonium assimilation. Only weak 15N-assimilation was observed after incubation with 15N-nitrate. Feeding foraminifers with 13C- and 15N-labelled food resulted in dinoflagellates that were labelled with 15N, thereby confirming the transfer of 15N-compounds from the digestive vacuoles of the foraminifer to the symbiotic dinoflagellates, likely through recycling of ammonium. These observations are important for N isotope-based paleoceanographic reconstructions, as they show that δ15N values recorded in the organic matrix in symbiotic species likely reflect ammonium recycling rather than alternative N sources, such as nitrates.
Derivations from the even parts into the odd parts for Lie superalgebras W and S
Creators: name: Liu, Wende
name: Liu, Baoling
Publisher: name: arXiv
Year: 2005
Subjects: subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics
subject: 17B40, 17B50

description: Let $\mathcal{W}$ and $\mathcal{S}$ denote the even parts of the general Witt superalgebra $W$ and the special superalgebra $S$ over a field of characteristic $ p>3,$ respectively. In this note, using the method of reduction on $\mathbb{Z}$-gradations, we determine the derivation space $\mathrm{Der}(\mathcal{W}, W_{\bar{1}})$ from $\mathcal{W}$ into $W_{\bar{1}} $ and the derivation space $\mathrm{Der}(\mathcal{S}, W_{\bar{1}})$ from $\mathcal{S}$ into $W_{\bar{1}}. $ In particular, the derivation space $\mathrm{Der}(\mathcal{S}, S_{\bar{1}})$ is determined.
description: 19 pages
Text S2 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts
Creators: name: LeKieffre, Charlotte
name: Spero, Howard J.
name: Fehrenbacher, Jennifer S.
name: Russell, Ann D.
name: Haojia Ren
name: Geslin, Emmanuelle
name: Meibom, Anders
Publisher: name: The Royal Society
Year: 2020
Subjects: subject: Microbiology
subject: FOS: Biological sciences
subject: Ecology
subject: 40308 Palaeontology (incl. Palynology)
subject: FOS: Earth and related environmental sciences

description: The symbiotic planktonic foraminifera Orbulina universa inhabits open ocean oligotrophic ecosystems where dissolved nutrients are scarce and often limit biological productivity. It has previously been proposed that O. universa meets its nitrogen (N) requirements by preying on zooplankton, and that its symbiotic dinoflagellates recycle metabolic ‘waste ammonium’ for their N pool. However, these conclusions were derived from bulk 15N-enrichment experiments and model calculations, and our understanding of N assimilation and exchange between the foraminifer host cell and its symbiotic dinoflagellates remains poorly constrained. Here, we present data from pulse-chase experiments with 13C-enriched inorganic carbon, 15N-nitrate and 15N-ammonium, as well as a 13C- and 15N- enriched heterotrophic food source, followed by TEM coupled to NanoSIMS isotopic imaging to visualize and quantify C and N assimilation and translocation in the symbiotic system. High levels of 15N-labelling were observed in the dinoflagellates and in foraminiferal organelles and cytoplasm after incubation with 15N-ammonium, indicating efficient ammonium assimilation. Only weak 15N-assimilation was observed after incubation with 15N-nitrate. Feeding foraminifers with 13C- and 15N-labelled food resulted in dinoflagellates that were labelled with 15N, thereby confirming the transfer of 15N-compounds from the digestive vacuoles of the foraminifer to the symbiotic dinoflagellates, likely through recycling of ammonium. These observations are important for N isotope-based paleoceanographic reconstructions, as they show that δ15N values recorded in the organic matrix in symbiotic species likely reflect ammonium recycling rather than alternative N sources, such as nitrates.
Genuine high-dimensional quantum steering
Creators: name: Designolle, Sébastien
name: Srivastav, Vatshal
name: Uola, Roope
name: Valencia, Natalia Herrera
name: McCutcheon, Will
name: Malik, Mehul
name: Brunner, Nicolas
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: High-dimensional quantum entanglement can give rise to stronger forms of nonlocal correlations compared to qubit systems, offering significant advantages for quantum information processing. Certifying these stronger correlations, however, remains an important challenge, in particular in an experimental setting. Here we theoretically formalise and experimentally demonstrate a notion of genuine high-dimensional quantum steering. We show that high-dimensional entanglement, as quantified by the Schmidt number, can lead to a stronger form of steering, provably impossible to obtain via entanglement in lower dimensions. Exploiting the connection between steering and incompatibility of quantum measurements, we derive simple two-setting steering inequalities, the violation of which guarantees the presence of genuine high-dimensional steering, and hence certifies a lower bound on the Schmidt number in a one-sided device-independent setting. We report the experimental violation of these inequalities using macro-pixel photon-pair entanglement certifying genuine high-dimensional steering. In particular, using an entangled state in dimension $d=31$, our data certifies a minimum Schmidt number of $n=15$.
description: 9 pages, 1 table, 5 figures
A search for circumstellar dust disks with ADONIS
Creators: name: Schuetz, O.
name: Boehnhardt, H.
name: Pantin, E.
name: Sterzik, M.
name: Els, S.
name: Hahn, J.
name: Henning, Th.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present results of a coronographic imaging search for circumstellar dust disks with the Adaptive Optics Near Infrared System (ADONIS) at the ESO 3.6m telescope in La Silla (Chile). 22 candidate stars, known to be orbited by a planet or to show infrared excess radiation, were examined for circumstellar material. In the PSF-subtracted images no clear disk was found. We further determine the detection sensitivities and outline how remaining atmospheric fluctuations still can hamper adaptive optics observations.
description: To appear in A&A, in press
Dynamics of the vacuum state in a periodically driven Rydberg chain
Creators: name: Mukherjee, Bhaskar
name: Sen, Arnab
name: Sen, Diptiman
name: Sengupta, K.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study the dynamics of the periodically driven Rydberg chain starting from the state with zero Rydberg excitations (vacuum state denoted by $|0\rangle$) using a square pulse protocol in the high drive amplitude limit. We show, using exact diagonalization for finite system sizes ($L\le 26$), that the Floquet Hamiltonian of the system, within a range of drive frequencies which we chart out, hosts a set of quantum scars which have large overlap with the $|0\rangle$ state. These scars are distinct from their counterparts having high overlap with the maximal Rydberg excitation state ($|\mathbb{Z}_2\rangle$); they coexist with the latter class of scars and lead to persistent coherent oscillations of the density-density correlator starting from the $|0\rangle$ state. We also identify special drive frequencies at which the system undergoes perfect dynamic freezing and provide an analytic explanation for this phenomenon. Finally, we demonstrate that for a wide range of drive frequencies, the system reaches a steady state with sub-thermal values of the density-density correlator. The presence of such sub-thermal steady states, which are absent for dynamics starting from the $|\mathbb{Z}_2\rangle$ state, imply a weak violation of the eigenstate thermalization hypothesis in finite sized Rydberg chains distinct from that due to the scar-induced persistent oscillations reported earlier. We conjecture that in the thermodynamic limit such states may exist as pre-thermal steady states that show anomalously slow relaxation. We supplement our numerical results by deriving an analytic expression for the Floquet Hamiltonian using a Floquet perturbation theory in the high amplitude limit which provides an analytic, albeit qualitative, understanding of these phenomena at arbitrary drive frequencies. We discuss experiments which can test our theory.
description: 18 pages and 17 figures including appendices
Die Bedeutung des diakonischen Selbstverständnisses für die generalistische Pflegeausbildung
Creators: name: Lorenz, Benjamin
Publisher: name: DWI-Jahrbuch – Diakoniewissenschaft in Forschung und Lehre
Year: 2023

description: DWI-Jahrbuch – Diakoniewissenschaft in Forschung und Lehre, Bd. 48: (2022/2023): Diakoniewissenschaft in Forschung und Lehre
The effect of {11}^B substitution on the superconductivity in MgCNi3
Creators: name: Klimczuk, T.
name: Avdeev, M.
name: Jorgensen, J. D.
name: Cava, R. J.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The crystal structure of boron doped superconducting MgC_{1-x}{11}^B_{x}Ni_{3}, studied by powder neutron diffraction, is reported. The solubility limit of boron is determined to be approximately x=0.16. The unit cell expands from a = 3.81089(2) to 3.81966(2) Angstroms as x increases from x=0 to x=0.155. Boron ({11}^B) doping decreases Tc with increasing x: from 7.09K (x=0) to 6.44K (x=0.155).
description: Submitted to Phys. Rev. B
Graduate recitals
Creators: name: Yang, Yung-Ching
Publisher: name: University of British Columbia
Year: 2009

description: The thesis for the Master of Music degree in Orchestral Instruments consists two full-length recitals, or the equivalent, with emphasis on solo works, but also including representative chamber works. The two full-length recitals were performed on November 14, 2003 and April 27, 2004.
Brauchen die Franziskanerbrüder vom Heiligen Kreuz eine andere Arbeits- und Führungskultur?
Creators: name: Langensiepen, Irina
Publisher: name: DWI-Jahrbuch – Diakoniewissenschaft in Forschung und Lehre
Year: 2023

description: DWI-Jahrbuch – Diakoniewissenschaft in Forschung und Lehre, Bd. 48: (2022/2023): Diakoniewissenschaft in Forschung und Lehre
The Effect of Allowance Allocations on Cap-and-Trade System Performance
Creators: name: Hahn, Robert W.
name: Stavins, Robert N.
name: Hahn, Robert W.
name: Stavins, Robert N.
Publisher: name: Unknown
Year: 2010
Subjects: subject: Environmental Economics and Policy
subject: Cap-and-Trade System
subject: Tradable Permits
subject: Coase Theorem
subject: Allowance Allocation

description: We examine an implication of the “Coase Theorem” which has had an important impact both on environmental economics and on public policy in the environmental domain. Under certain conditions, the market equilibrium in a cap-and-trade system will be cost-effective and independent of the initial allocation of tradable rights. That is, the overall cost of achieving a given aggregate emission reduction will be minimized, and the final allocation of permits will be independent of the initial allocation. We call this the independence property. This property is very important because it allows equity and efficiency concerns to be separated in a relatively straightforward manner. In particular, the property means that the government can establish the overall pollution-reduction goal for a cap-and-trade system by setting the cap, and leave it up to the legislature – such as the U.S. Congress – to construct a constituency in support of the program by allocating the allowances to various interests without affecting either the environmental performance of the system or its aggregate social costs. Our primary objective in this paper is to examine the conditions under which the independence property is likely to hold – both in theory and in practice. A number of factors can call the independence property into question theoretically, including market power, transaction costs, non-cost-minimizing behavior, and conditional allowance allocations. We find that, in practice, there is support for the independence property in some, but not all cap-and-trade applications.
Density-functional study of oxygen adsorption on Mo(112)
Creators: name: Kiejna, Adam
name: Nieminen, R. M.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Atomic oxygen adsorption on the Mo(112) surface has been investigated by means of first-principles total energy calculations. Among the variety of possible adsorption sites it was found that the bridge sites between two Mo atoms of the topmost row are favored for O adsorption at low and medium coverages. At about one monolayer coverage oxygen atoms prefer to adsorb in a quasi-threefold hollow sites coordinated by two first-layer Mo atoms and one second layer atom. The stability of a structural model for an oxygen-induced $p(2\times 3)$ reconstruction of the missing-row type is examined.
description: 6 pages, 6 postscript figures, RevTeX
Optimal allocation of quantum resources
Creators: name: Salazar, Roberto
name: Biswas, Tanmoy
name: Czartowski, Jakub
name: Życzkowski, Karol
name: Horodecki, Paweł
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The optimal allocation of resources is a crucial task for their efficient use in a wide range of practical applications in science and engineering. This paper investigates the optimal allocation of resources in multipartite quantum systems. In particular, we show the relevance of proportional fairness and optimal reliability criteria for the application of quantum resources. Moreover, we present optimal allocation solutions for an arbitrary number of qudits using measurement incompatibility as an exemplary resource theory. Besides, we study the criterion of optimal equitability and demonstrate its relevance to scenarios involving several resource theories such as nonlocality vs local contextuality. Finally, we highlight the potential impact of our results for quantum networks and other multi-party quantum information processing, in particular to the future Quantum Internet.
Analysis and Visualization of Index Words from Audio Transcripts of Instructional Videos
Creators: name: Haubold, Alexander
name: Kender, John R.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Information Retrieval (cs.IR)
subject: Multimedia (cs.MM)
subject: FOS: Computer and information sciences
subject: H.3.1;H.3.3;I.2.10

description: We introduce new techniques for extracting, analyzing, and visualizing textual contents from instructional videos of low production quality. Using Automatic Speech Recognition, approximate transcripts (H75% Word Error Rate) are obtained from the originally highly compressed videos of university courses, each comprising between 10 to 30 lectures. Text material in the form of books or papers that accompany the course are then used to filter meaningful phrases from the seemingly incoherent transcripts. The resulting index into the transcripts is tied together and visualized in 3 experimental graphs that help in understanding the overall course structure and provide a tool for localizing certain topics for indexing. We specifically discuss a Transcript Index Map, which graphically lays out key phrases for a course, a Textbook Chapter to Transcript Match, and finally a Lecture Transcript Similarity graph, which clusters semantically similar lectures. We test our methods and tools on 7 full courses with 230 hours of video and 273 transcripts. We are able to extract up to 98 unique key terms for a given transcript and up to 347 unique key terms for an entire course. The accuracy of the Textbook Chapter to Transcript Match exceeds 70% on average. The methods used can be applied to genres of video in which there are recurrent thematic words (news, sports, meetings,...)
description: 2004 IEEE International Workshop on Multimedia Content-based Analysis and Retrieval; 20 pages, 8 figures, 7 tables
Supplementary materials and methods from Genome-wide patterns of divergence and introgression after secondary contact between Pungitius sticklebacks
Creators: name: Yamasaki, Yo Y.
name: Kakioka, Ryo
name: Takahashi, Hiroshi
name: Toyoda, Atsushi
name: Nagano, Atsushi J.
name: Machida, Yoshiyasu
name: Møller, Peter R.
name: Kitano, Jun
Publisher: name: The Royal Society
Year: 2020
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Evolutionary Biology
subject: 60408 Genomics

description: Speciation is a continuous process. Although it is known that differential adaptation can initiate divergence even in the face of gene flow, we know relatively little about the mechanisms driving complete reproductive isolation and the genomic patterns of divergence and introgression at the later stages of speciation. Sticklebacks contain many pairs of sympatric species differing in levels of reproductive isolation and divergence history. Nevertheless, most previous studies have focused on young species pairs. Here, we investigated two sympatric stickleback species, Pungitius pungitius and P. sinensis, whose habitats overlap in eastern Hokkaido; these species show hybrid male sterility, suggesting that they may be at a late stage of speciation. Our demographic analysis using whole-genome sequence data showed that these species split 1.73 Ma and came into secondary contact 37 200 years ago after a period of allopatry. This long period of allopatry might have promoted the evolution of intrinsic incompatibility. Although we detected on-going gene flow and signatures of introgression, overall genomic divergence was high, with considerable heterogeneity across the genome. The heterogeneity was significantly associated with variation in recombination rate. This sympatric pair provides new avenues to investigate the late stages of the stickleback speciation continuum.This article is part of the theme issue ‘Towards the completion of speciation: the evolution of reproductive isolation beyond the first barriers’.
The Effect of Risk, Ambiguity and Coordination on Farmers’ Adaptation to Climate Change: A Framed Field Experiment
Creators: name: Alpizar, Francisco
name: Carlsson, Fredrik
name: Naranjo, Maria
name: Alpizar, Francisco
name: Carlsson, Fredrik
name: Naranjo, Maria
Publisher: name: Unknown
Year: 2010
Subjects: subject: Environmental Economics and Policy
subject: Risk Aversion
subject: Ambiguity Aversion
subject: Technology Adoption
subject: Climate change
subject: Field Experiment

description: The risk of losses of income and productive means due to adverse weather associated to climate change can significantly differ between farmers sharing a productive landscape. It is important to learn more about how farmers react to different levels of risk, under measurable and unmeasurable uncertainty. Moreover, the costs associated to investments in reduced vulnerability to climatic events are likely to exhibit economies of scope. We explore these issues using a framed field experiment that captures realistically the main characteristics of production, and the likely weather related losses of premium coffee farmers in Tarrazu, Costa Rica. Given that the region recently was severely hit by an extreme, albeit very infrequent, climatic event, we expected to observe, and found high levels of risk aversion, but we do observe farmers making trade-offs under different risk levels. Although hard to disentangle at first sight given the high level of risk aversion, we find that farmers opt more frequently for safe options in a setting characterized by unknown risk. Finally, we find that farmers to a large extent are able to coordinate their decisions in order to achieve a lower cost of adaptation, and that communication among farmers strongly facilitates coordination.
Origin of the Immirzi Parameter
Creators: name: Chou, Chung-Hsien
name: Tung, Roh-Suan
name: Yu, Hoi-Lai
Publisher: name: arXiv
Year: 2005
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Using quadratic spinor techniques we demonstrate that the Immirzi parameter can be expressed as ratio between scalar and pseudo-scalar contributions in the theory and can be interpreted as a measure of how Einstein gravity differs from a generally constructed covariant theory for gravity. This interpretation is independent of how gravity is quantized. One of the important advantage of deriving the Immirzi parameter using the quadratic spinor techniques is to allow the introduction of renormalization scale associated with the Immirzi parameter through the expectation value of the spinor field upon quantization.
Enhancing Radiography Education Through Immersive Virtual Reality
Creators: name: Acosta, Sophia
Publisher: name: Zenodo
Year: 2025
Subjects: subject: Innovations in radiography training
subject: Medical imaging
subject: Radiography
subject: Education
subject: Technology, Radiologic
subject: radiologic technology
subject: Immersive learning environment
subject: Hybrid training models
subject: Virtual Reality
subject: Simulation software
subject: Patient Simulation
subject: Simulation Training/classification

description: Our paper, Enhancing Radiography Education Through Immersive Virtual Reality, explores the integration of Virtual Reality (VR) alongside traditional Siemens radiographic equipment in radiography education. It presents a comparative study of traditional and hybrid training models, demonstrating that VR-enhanced learning significantly improves student performance in radiographic positioning, room setup, and knowledge retention. The study, involving 165 first-year radiography students, provides strong statistical evidence that hybrid training methods lead to greater precision, efficiency, and cost savings in medical imaging education. The financial analysis highlights the scalability and sustainability of VR-based training, suggesting it as a viable alternative to conventional methods. Given the increasing demand for effective, immersive learning experiences in healthcare education, my research makes a valuable contribution to the field, supporting the adoption of VR as an essential component of radiography training.