cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Combinatorial Hopf algebraic description of the multiscale renormalization in quantum field theory
Creators: name: Krajewski, Thomas
name: Rivasseau, Vincent
name: Tanasa, Adrian
Publisher: name: arXiv
Year: 2012
Subjects: subject: Combinatorics (math.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We define in this paper several Hopf algebras describing the combinatorics of the so-called multi-scale renormalization in quantum field theory. After a brief recall of the main mathematical features of multi-scale renormalization, we define assigned graphs, that are graphs with appropriate decorations for the multi-scale framework. We then define Hopf algebras on these assigned graphs and on the Gallavotti-Nicolò trees, particular class of trees encoding the supplementary informations of the assigned graphs. Several morphisms between these combinatorial Hopf algebras and the Connes-Kreimer algebra are given. Finally, scale dependent couplings are analyzed via this combinatorial algebraic setting.
description: 26 pages, 3 figures; the presentation of the results has been reorganized. Several details of various proofs are given and some references have been added
Random walks with interacting coordinates
Creators: name: MENG SHI
Publisher: name: Monash University
Year: 2018
Subjects: subject: 10404 Probability Theory
subject: FOS: Mathematics
subject: 10406 Stochastic Analysis and Modelling

description: Random walks with interacting coordinates is an interesting generalisation of random walks in multiple dimensions. The study of random walks is one of the cornerstones of probability theory. Allowing interaction between coordinates is am important aspect of the study. Bootstrap random walks allow for a strong dependence between the coordinates. This thesis examines the long-term behaviours of the bootstrap random walks and shows that the strong dependence vanished in the long run under certain conditions.
ON THE ASYMPTOTIC ANALYSIS OF RANDOM WALKS WITH DEPENDENT INCREMENTS
Creators: name: YUNXUAN LIU
Publisher: name: Monash University
Year: 2018
Subjects: subject: 10404 Probability Theory
subject: FOS: Mathematics

description: In this thesis, we study the limiting behavior of bootstrap random walk and oncereinforced random walk on regular tree. They are two examples of the random walk with dependent increments. In particular, we prove the invariance principle for the 2K + 1-dimensional bootstrap random walk and compute the covariance matrix for the limiting Brownian motion. Moreover, by considering the Markovian property for the increment process, we obtain a recurrence/transience analysis. For the second topic, we actually consider the MAD random walk and treat once-reinforced random walk as a special case. We illustrate a coupling between the MAD walk and the underlying environment, and extend this coupling to certain subtrees. With the inspiration from other people's work, we provide a weak large deviation principle for the local times and, as a byproduct, we prove the invariance principle for the distance of MAD random walk from the root.
Dnmt1 has de novo activity targeted to transposable elements
Creators: name: Haggerty, Chuck
name: Kretzmer, Helene
name: Riemenschneider, Christina
name: Kumar, Abhishek Sampath
name: Mattei, Alexandra L.
name: Bailly, Nina
name: Gottfreund, Judith
name: Giesselmann, Pay
name: Weigert, Raha
name: Meissner, Alexander
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Chromatin
subject: Developmental biology
subject: DNA methylation
subject: Epigenomics
subject: 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::570 Biowissenschaften; Biologie

description: DNA methylation plays a critical role during development, particularly in repressing retrotransposons. The mammalian methylation landscape is dependent on the combined activities of the canonical maintenance enzyme Dnmt1 and the de novo Dnmts, 3a and 3b. Here, we demonstrate that Dnmt1 displays de novo methylation activity in vitro and in vivo with specific retrotransposon targeting. We used whole-genome bisulfite and long-read Nanopore sequencing in genetically engineered methylation-depleted mouse embryonic stem cells to provide an in-depth assessment and quantification of this activity. Utilizing additional knockout lines and molecular characterization, we show that the de novo methylation activity of Dnmt1 depends on Uhrf1, and its genomic recruitment overlaps with regions that enrich for Uhrf1, Trim28 and H3K9 trimethylation. Our data demonstrate that Dnmt1 can catalyze DNA methylation in both a de novo and maintenance context, especially at retrotransposons, where this mechanism may provide additional stability for long-term repression and epigenetic propagation throughout development.
P.-P. Sagave, 1871 Berlin-Paris. Capitale du Reich et capitale du monde suivi de Paris-Berlin: à l'aube du troisième millénaire. Traduit de l'allemand par O. Mannoni, 1995 (A. Wirsching) ; S. Audoin-Rouzeau, A. Becker, La Grande Guerre 1914-1918, 1998
Creators: name: Deist, W.
Publisher: name: Francia
Year: 2019

description: Francia, Bd. 28 Nr. 3 (2001)
Solving the Graph Isomorphism Problem with a Quantum Annealer
Creators: name: Hen, Itay
name: Young, A. P.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We propose a novel method using a quantum annealer -- an analog quantum computer based on the principles of quantum adiabatic evolution -- to solve the Graph Isomorphism problem, in which one has to determine whether two graphs are isomorphic (i.e., can be transformed into each other simply by a relabeling of the vertices). We demonstrate the capabilities of the method by analyzing several types of graph families, focusing on graphs with particularly high symmetry called strongly regular graphs (SRG's). We also show that our method is applicable, within certain limitations, to currently available quantum hardware such as "D-Wave One".
description: 9 pages, 6 figures. arXiv admin note: text overlap with arXiv:1002.3003 by other authors
The whole is greater than the sum of its parts: profiles of multiple mental health risk factors using Latent class analysis
Creators: name: Göbel, Kristin
name: Cohrdes, Caroline
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Mental health
subject: Youth
subject: Multiple risk factors
subject: Latent class analysis
subject: Depression
subject: 100 Philosophie und Psychologie::150 Psychologie::150 Psychologie

description: Background The exposure to an accumulation of various risk factors during childhood and adolescence relative to a single risk is associated with poorer mental health. Identification of distinct constellations of risk factors is an essential step towards the development of effective prevention strategies of mental disorders. A Latent class analysis (LCA) extracts different combinations of risk factors or subgroups and examines the association between profiles of multiple risk and mental health outcomes. Methods The current study used longitudinal survey data (KiGGS) of 10,853 German children, adolescents and young adults. The LCA included 27 robust risk and protective factors across multiple domains for mental health. Results The LCA identified four subgroups of individuals with different risk profiles: a basic-risk (51.4%), high-risk (23.4%), parental-risk (11.8%) and social-risk class (13.4%). Multiple risk factors of the family domain, in particular family instability were associated with negative mental health outcomes (e.g. mental health problems, depression, ADHD) and predominately comprised late adolescent girls. The social environment represented a more common risk domain for young males. Conclusion The understanding of multiple risk and different risk “profiles” helps to understand and adjust targeted interventions with a focus on vulnerable groups.
Transversal This, Transversal That
Creators: name: DARCY GORDON BEST
Publisher: name: Monash University
Year: 2019
Subjects: subject: 10104 Combinatorics and Discrete Mathematics (excl. Physical Combinatorics)
subject: FOS: Mathematics

description: Latin squares are two-dimensional patterns of symbols. Studied since the 18th century, they now find numerous applications in communication technologies and scheduling problems. A transversal is a balanced selection of symbols within a Latin square. In this thesis, we study the number of, existence of, and structure of transversals in Latin squares and similar objects. In certain sizes of squares, we prove that the number of transversals must be a multiple of four. We also find the first known bound on the number of symbols needed to guarantee the existence of a transversal.
High-resolution 14C bomb peak dating and climate response analyses of subseasonal stable isotope signals in wood of the African baobab – a case study from Oman
Creators: name: Slotta, Franziska
name: Wacker, Lukas
name: Riedel, Frank
name: Heußner, Karl-Uwe
name: Hartmann, Kai
name: Helle, Gerhard
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: African baobab
subject: paleoclimatology
subject: dendroclimatology
subject: 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie::550 Geowissenschaften

description: The African baobab, Adansonia digitata L., has great paleoclimatological potential because of its wide distributional range and millennial length life span. However, dendroclimatological approaches are hampered by dating uncertainties due to its unique, parenchyma-dominated stem anatomy. Here, securely dated time series of annual wood increment growth and intra-ring stable isotopes of carbon and oxygen of cellulose for a baobab tree from Oman covering 1941 to 2005 were established and tested for relationships to hydroclimate variability. Precise dating with the atomic bomb peak (ABP) using highly resolved 14C measurements confirmed the annual character of the baobab's growth rings. F14C values of tree-ring cellulose were found up to 8.8 % lower than in the corresponding atmospheric CO2 for the period around the ABP, which in conjunction with a considerable autocorrelation of the δ13C series points to the incorporation of previous year's carbon contributing to the average age of intra-ring wood samples. F14C of terminal parenchyma bands, marking the tree-ring boundaries, were found to be considerably younger than their corresponding tree ring, indicating that parenchyma tissue is alive for many years, probably undergoing cell division and structural reorganization and contributing to secondary growth. In contrast to the δ13C time series, no significant autocorrelation was found in the δ18O series of tree-ring cellulose despite the enormous water storage potential of this stem-succulent tree species. Year-to-year variability in tree-ring width and stable isotope ratios revealed radial stem growth and the geochemistry of wood cellulose are influenced by fluctuations in the hydroclimate. In particular, δ18O was found to be a good climate proxy, followed by tree-ring width and δ13C. Tree-ring width and intra-ring δ18Omin correlated well with each other and with precipitation amount for the period from pre-monsoon May to the end of the monsoon season in September/October. Intra-annual stable isotope courses were found to be rather similar for both δ13C and δ18O. Years with particularly low monsoon rain were reflected by increased stable isotope values in the mid-section of intra-annual courses. Distinct patterns with low subseasonal isotope values seem indicative for years with heavy rainfall events from pre-monsoonal cyclones. Rain events from post-monsoonal cyclones may also be recorded; however, only 2 years of observation prevented a more conclusive evaluation.
A Numerical Exploration of the Spherically Symmetric SU(2) Einstein-Yang-Mills Equations
Creators: name: DANIEL ROBERT JACKSON
Publisher: name: Monash University
Year: 2019
Subjects: subject: 10302 Numerical Solution of Differential and Integral Equations
subject: FOS: Mathematics
subject: 10504 Mathematical Aspects of General Relativity

description: The Einstein-Yang-Mills equations describe how a spacetime can curve when it contains a generalisation of an electromagnetic field known as a Yang-Mills field. This thesis develops an efficient numerical code to solve the equations and finds new self-similar behaviour that occurs as black holes are just on the cusp of forming, contributing to a better understanding of general relativity, Einstein’s theory of gravity.
Energy Transfer in a Molecular Motor in Kramers' Regime
Creators: name: Challis, K. J.
name: Jack, Michael W.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: We present a theoretical treatment of energy transfer in a molecular motor described in terms of overdamped Brownian motion on a multidimensional tilted periodic potential. The tilt acts as a thermodynamic force driving the system out of equilibrium and, for non-separable potentials, energy transfer occurs between degrees of freedom. For deep potential wells, the continuous theory transforms to a discrete master equation that is tractable analytically. We use this master equation to derive formal expressions for the hopping rates, drift, diffusion, efficiency and rate of energy transfer in terms of the thermodynamic force. These results span both strong and weak coupling between degrees of freedom, describe the near and far from equilibrium regimes, and are consistent with generalized detailed balance and the Onsager relations. We thereby derive a number of diverse results for molecular motors within a single theoretical framework.
description: 8 pages, 3 figures
Structural complexity influences the ecosystem engineering effects of in-stream large wood
Creators: name: Cashman, Matthew J.
name: Harvey, Gemma L.
name: Wharton, Geraldene
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: fluvial geomorphology
subject: large wood
subject: physical habitat diversity
subject: river restoration
subject: structural complexity
subject: 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie::550 Geowissenschaften

description: Large wood (LW) is an ecosystem engineer and keystone structure in river ecosystems, influencing a range of hydromorphological and ecological processes and contributing to habitat heterogeneity and ecosystem condition. LW is increasingly being used in catchment restoration, but restored LW jams have been observed to differ in physical structure to naturally occurring jams, with potential implications for restoration outcomes. This article examines the structural complexity and ecosystem engineering effects of LW jams at four sites with varying management intensity incorporating natural and restored wood. Our results reveal: (i) structural complexity and volume of jams was highest in the site with natural jams and low intensity riparian management, and lowest in the suburban site with simple restored jams; and (ii) that structural complexity influences the ecosystem engineering role of LW, with more complex jams generating the greatest effects on flow hydraulics (flow concentration, into bed flows) and sediment characteristics (D50, organic content, fine sediment retention) and the simplest flow deflector-style restored jams having the least pronounced effects. We present a conceptual model describing a continuum of increasing jam structural complexity and associated hydromorphological effects that can be used as a basis for positioning and evaluating other sites along the management intensity spectrum to help inform restoration design and best practice.
Cosmological Newtonian Limits on Large Scales
Creators: name: CHAO LIU
Publisher: name: Monash University
Year: 2019
Subjects: subject: 10199 Pure Mathematics not elsewhere classified
subject: FOS: Mathematics
subject: 10299 Applied Mathematics not elsewhere classified
subject: 10110 Partial Differential Equations
subject: 10504 Mathematical Aspects of General Relativity

description: This thesis is about the rigid cosmological Newtonian limits on large time and space scales and answers the following fundamental question: On what space and time scales can Newtonian cosmological simulations be trusted to approximate relativistic cosmologies? We will resolve this question with small initial data and the positive cosmological constant condition, and answer it on large spacetime scales and establish, under suitable assumptions, the existence of realistic inhomogeneous cosmological solutions that (1) admit a foliation by spacelike (i.e. constant time) hypersurfaces diffeomorphic to R^3, (2) exist globally to the future, (3) can be approximated to arbitrary precision uniformly to the future by a Newtonian solution, and (4) represent non-linear perturbations of a FLRW fluid solution.
Faint Submillimter Galaxy Counts at 450 micron
Creators: name: Chen, Chian-Chou
name: Cowie, Lennox L.
name: Barger, Amy J.
name: Casey, Caitlin M.
name: Lee, Nicholas
name: Sanders, David B.
name: Wang, Wei-Hao
name: Williams, Jonathan P.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present the results of SCUBA2 observations at 450 micron and 850 micron of the field lensed by the massive cluster A370. With a total survey area > 100 arcmin2 and 1 sigma sensitivities of 3.92 and 0.82 mJy/beam at 450 and 850 micron respectively, we find a secure sample of 20 sources at 450 micron and 26 sources at 850 micron with a signal-to-noise ratio > 4. Using the latest lensing model of A370 and Monte Carlo simulations, we derive the number counts at both wavelengths. The 450 micron number counts probe a factor of four deeper than the counts recently obtained from the Herschel Space Telescope at similar wavelengths, and we estimate that ~47-61% of the 450 micron extragalactic background light (EBL) resolved into individual sources with 450 micron fluxes greater than 4.5 mJy. The faint 450 micron sources in the 4 sigma sample have positional accuracies of 3 arcseconds, while brighter sources (signal-to-noise > 6 sigma) are good to 1.4 arcseconds. Using the deep radio map (1 sigma ~ 6 uJy) we find that the percentage of submillimeter sources having secure radio counterparts is 85% for 450 micron sources with intrinsic fluxes > 6 mJy and 67% for 850 micron sources with intrinsic fluxes > 4 mJy. We also find that 67% of the > 4 sigma 450 micron sources are detected at 850 micron, while the recovery rate at 450 micron of > 4 sigma 850 micron sources is 54%. Combined with the source redshifts estimated using millimetric flux ratios, the recovered rate is consistent with the scenario where both 450 micron and 20 cm emission preferentially select lower redshift dusty sources, while 850 micron emission traces a higher fraction of dusty sources at higher redshifts. [Abridge]
description: 22 pages, 14 figures, ApJ in press. Minor changes to the submitted version
Circuit QED with fluxonium qubits: theory of the dispersive regime
Creators: name: Zhu, Guanyu
name: Ferguson, David G.
name: Manucharyan, Vladmir E.
name: Koch, Jens
Publisher: name: arXiv
Year: 2012
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In circuit QED, protocols for quantum gates and readout of superconducting qubits often rely on the dispersive regime, reached when the qubit-photon detuning Δ is large compared to their mutual coupling strength. For qubits including the Cooper-pair box and transmon, selection rules dramatically restrict the contributions to dispersive level shifts χ. By contrast, without selection rules many virtual transitions contribute to χ and can produce sizable dispersive shifts even at large detuning. We present theory for a generic multi-level qudit capacitively coupled to one or multiple harmonic modes, and give general expressions for the effective Hamiltonian in second and fourth order perturbation theory. Applying our results to the fluxonium system, we show that the absence of strong selection rules explains the surprisingly large dispersive shifts observed in experiments and also leads to the prediction of a two-photon vacuum Rabi splitting. Quantitative predictions from our theory are in good agreement with experimental data over a wide range of magnetic flux and reveal that fourth-order resonances are important for the phase modulation observed in fluxonium spectroscopy.
description: 16 pages, 10 figures; revised version with minor corrections
Algorithms for Computing Abelian Periods of Words
Creators: name: Fici, Gabriele
name: Lecroq, Thierry
name: Lefebvre, Arnaud
name: Prieur-Gaston, Elise
Publisher: name: arXiv
Year: 2012
Subjects: subject: Data Structures and Algorithms (cs.DS)
subject: Discrete Mathematics (cs.DM)
subject: Combinatorics (math.CO)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Constantinescu and Ilie (Bulletin EATCS 89, 167--170, 2006) introduced the notion of an \emph{Abelian period} of a word. A word of length $n$ over an alphabet of size $σ$ can have $Θ(n^{2})$ distinct Abelian periods. The Brute-Force algorithm computes all the Abelian periods of a word in time $O(n^2 \times σ)$ using $O(n \times σ)$ space. We present an off-line algorithm based on a $\sel$ function having the same worst-case theoretical complexity as the Brute-Force one, but outperforming it in practice. We then present on-line algorithms that also enable to compute all the Abelian periods of all the prefixes of $w$.
description: Accepted for publication in Discrete Applied Mathematics
Spin–spin interactions and spin delocalisation in a doped organic semiconductor probed by EPR spectroscopy
Creators: name: Tait, Claudia E.
name: Reckwitz, Anna
name: Arvind, Malavika
name: Neher, Dieter
name: Bittl, Robert
name: Behrends, Jan
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: spin–spin interactions
subject: spin delocalisation
subject: organic semiconductor
subject: 500 Naturwissenschaften und Mathematik::530 Physik::530 Physik

description: The enhancement and control of the electrical conductivity of organic semiconductors is fundamental for their use in optoelectronic applications and can be achieved by molecular doping, which introduces additional charge carriers through electron transfer between a dopant molecule and the organic semiconductor. Here, we use Electron Paramagnetic Resonance (EPR) spectroscopy to characterise the unpaired spins associated with the charges generated by molecular doping of the prototypical organic semiconductor poly(3-hexylthiophene) (P3HT) with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) and tris(pentafluorophenyl)borane (BCF). The EPR results reveal the P3HT radical cation as the only paramagnetic species in BCF-doped P3HT films and show evidence for increased mobility of the detected spins at high doping concentrations as well as formation of antiferromagnetically coupled spin pairs leading to decreased spin concentrations at low temperatures. The EPR signature for F4TCNQ-doped P3HT is found to be determined by spin exchange between P3HT radical cations and F4TCNQ radical anions. Results from continuous-wave and pulse EPR measurements suggest the presence of the unpaired spin on P3HT in a multitude of environments, ranging from free P3HT radical cations with similar properties to those observed in BCF-doped P3HT, to pairs of dipolar and exchange-coupled spins on P3HT and the dopant anion. Characterisation of the proton hyperfine interactions by ENDOR allowed quantification of the extent of spin delocalisation and revealed reduced delocalisation in the F4TCNQ-doped P3HT films.
Unified theory of spin-dynamics in a two dimensional electron gases with arbitrary spin-orbit coping strength at finite temperature
Creators: name: Liu, Xin
name: Sinova, Jairo
Publisher: name: arXiv
Year: 2012
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We study the spin dynamics in the presence of impurity and electron-electron (e-e) scattering in a III-V semiconductor quantum well with arbitrary spin-orbit coupling (SOC) strength and symmetry at finite temperature. We derive the coupled spin-charge dynamic equations in the presence of inelastic scattering and provide a new formalism that describes the spin relaxation and dynamics in both the weak and the strong SOC regime in a unified way. In the weak SOC regime, as expected, our theory reproduces all previous zero-temperature results, most of which have focused on impurity-scattering induced spin-charge dynamics. In the regime where the strength of the Rashba and linear Dresselhaus SOC match, known as the SU(2) symmetry point, experiments have observed the spin-helix mode with a large spin-lifetime whose unexplained non-monotonic temperature dependence peaks at around 75 K. As a key test of our theory, we are able to naturally explain quantitatively this non-monotonic dependence and show that it arises as a competition between the Dyakonov-Perel mechanism, suppressed at the SU(2) point, and the Elliott-Yafet mechanism. In the strong SOC regime, we show that our theory directly reproduces the only previous known analytical result at the SU(2) symmetry point in the ballistic regime. It also explains, as we have shown previously, the rise of damped oscillating dynamics when the electron scattering time is larger than half of the spin precession time due to the SOC. Hence, we provide a unified theory of the spin-dynamics in two dimensional electron gases in the full phase diagram experimentally accessible.
description: 15 pages, 4 figures
Rumour Spreading with a Delaying Scheme
Creators: name: YOZEF GIOVANNI TJANDRA
Publisher: name: Monash University
Year: 2017
Subjects: subject: Probability
subject: 10104 Combinatorics and Discrete Mathematics (excl. Physical Combinatorics)
subject: FOS: Mathematics

description: Randomised rumour spreading scheme is an extremely simple and powerful model to represent a propagation of information within members of a network. We studied a particular variation of the rumour spreading scheme where the informed individuals are periodically absent from the spreading activity with a certain rate called the switching rate. We quantified the running time of the scheme and showed that a switching rate threshold function exists in the sense that the expected delay time is negligible if and only if the switching rate is significantly smaller than the threshold function.
Zu einem Beschlag aus Brno-Malomĕřice
Creators: name: Gebhard, Rupert
Publisher: name: Germania : Anzeiger der Römisch-Germanischen Kommission des Deutschen Archäologischen Instituts
Year: 2019

description: -
description: Germania : Anzeiger der Römisch-Germanischen Kommission des Deutschen Archäologischen Instituts, Bd. 67 Nr. 2 (1989)
Inibição em Microrganismos Anaeróbios por Cádmio (Cd2+) na Remoção de Matéria Orgânica
Creators: name: Fulvio Toledo Martins, Marco
name: Pozzi, Eloisa
name: Tallarico Saia, Flavia
name: Mockaitis, Gustavo
name: Zaiat, Marcelo
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 400410
subject: Wastewater treatment processes

description: O presente trabalho avaliou a toxicidade aguda da presença do íon cádmio (Cd2+) na atividade metanogênica específica, utilizando acetato como fonte de carbono (1280 mg O2·L-1, em termos de DQO). O experimento consistiu em um ensaio em batelada, realizado em frascos Duran® em condições anaeróbias a 30 °C, onde foram monitorados pressão no “headspace” e as concentrações de CH4 e CO2. Na fase líquida, foram monitorados o pH e a concentração de matéria orgânica em termos de DQO. Foram utilizados cinco biorreatores com adição Cd2+ de 0 (controle), 5, 10, 25 e 100 mg Cd2+·L-1. A atividade metanogênica específica da biomassa exposta ao cádmio variou de 0.6 mmol CH4·L/g SVT·h (5 mg Cd2+·L-1) a 0.9 mmol CH4·L/g SVT·h (100 mg Cd2+·L-1). Os perfis de bandas obtidos por DGGE mostraram diferença entre as comunidades dos domínios Bacteria e Archaea, analisados pelo índice de similaridade de Pearson
A Lacustrine Biomarker Record From Rebun Island Reveals a Warm Summer Climate in Northern Japan During the Early Middle Holocene Due to a Stronger North Pacific High
Creators: name: Yamamoto, Masanobu
name: Wang, Fangxian
name: Irino, Tomohisa
name: Suzuki, Kenta
name: Yamada, Kazuyoshi
name: Haraguchi, Tsuyoshi
name: Gotanda, Katsuya
name: Yonenobu, Hitoshi
name: Chen, Xuan-Yu
name: Tarasov, Pavel
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: climate change
subject: Northern Japan
subject: holocene
subject: lateglacial
subject: Biomarkers
subject: rebun
subject: RK12
subject: 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie::550 Geowissenschaften

description: The summer climate of northern Japan since the last glacial period has likely been determined by atmospheric and oceanic dynamics, such as changes in the North Pacific High, the position of the westerlies, the Kuroshio Current, the Tsushima Warm Current (TWC), and the East Asian summer monsoon. However, it is unclear which factor has been most important. In this study, we analyzed leaf wax δ13C and δD and glycerol dialkyl glycerol tetraethers (GDGTs) in sediments from Lake Kushu, Rebun Island, northern Japan, and discuss changes in climate over the past 17,000 years. The GDGT-based temperature, the averaged chain length, δ13C and δD of long-chain n-fatty acids indicated that the climate was cold during the Oldest Dryas period ∼16 ka and warm in the early Middle Holocene from ∼9 to 6 ka. This climate change is consistent with the sea surface temperature in the Kuroshio–Oyashio transition, but inconsistent with changes in the TWC in the Sea of Japan. The results imply that the summer climate of northern Japan was controlled mainly by changes in the development of the North Pacific High via changes in the position of the westerly jet and East Asian summer monsoon rainfall, whereas the influence of the TWC was limited over a millennial timescale.
Loss Tolerance with a Concatenated Graph State
Creators: name: Herrera-Martí, David A.
name: Rudolph, Terry
Publisher: name: arXiv
Year: 2012
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A new way of addressing loss errors is introduced which combines ideas from measurement-based quantum computation and concatenated quantum codes, allowing for universal quantum computation. It is shown that for the case where leakage is detected upon measurement, the scheme performs well under 23% loss rate. For loss rates below 10%, this approach performs better than the best scheme known up to date [Phys. Rev.Lett., 97(12):120501]. If lost qubits are tagged prior to measurement, it can tolerate up to 50% loss. The overhead per logical qubit is shown to be significantly lower than other schemes. The obtention of the threshold is entirely analytic.
description: 8 pages, 7 figures, 5 tables
Hamiltonian evolutions of twisted gons in $\RP^n$
Creators: name: Beffa, Gloria Marí
name: Wang, Jing Ping
Publisher: name: arXiv
Year: 2012
Subjects: subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences

description: In this paper we describe a well-chosen discrete moving frame and their associated invariants along projective polygons in $\RP^n$, and we use them to write explicit general expressions for invariant evolutions of projective $N$-gons. We then use a reduction process inspired by a discrete Drinfeld-Sokolov reduction to obtain a natural Hamiltonian structure on the space of projective invariants, and we establish a close relationship between the projective $N$-gon evolutions and the Hamiltonian evolutions on the invariants of the flow. We prove that {any} Hamiltonian evolution is induced on invariants by an evolution of $N$-gons - what we call a projective realization - and we give the direct connection. Finally, in the planar case we provide completely integrable evolutions (the Boussinesq lattice related to the lattice $W_3$-algebra), their projective realizations and their Hamiltonian pencil. We generalize both structures to $n$-dimensions and we prove that they are Poisson. We define explicitly the $n$-dimensional generalization of the planar evolution (the discretization of the $W_n$-algebra) and prove that it is completely integrable, providing also its projective realization.
Mathematical and numerical analysis of miscible displacement through porous media
Creators: name: Talbot, Kyle
Publisher: name: Monash University
Year: 2017
Subjects: Uncategorized

description: This thesis documents some recent advances in the mathematical and numerical analysis of a model describing the single-phase, miscible displacement through a porous medium of one incompressible fluid by another. The model is an initial-boundary value problem for a nonlinearly-coupled elliptic-parabolic system for the pressure of the fluid mixture, and the concentration of one of the components in the mixture.

 The thesis proves three main results for this model. Following standard approximation techniques, we prove the existence of weak solutions to the model with measure source terms and a diffusion-dispersion tensor that grows linearly with the Darcy velocity. Retaining the measure source terms, we extend this result to establish existence as the molecular diffusion in the diffusion-dispersion tensor vanishes. The third result is a unified convergence analysis of numerical schemes for the model, conducted using the framework of the Gradient Discretisation Method. Without assuming regularity or uniqueness of the solution to the model, we show that approximate concentrations converge uniformly-in-time.

 The last result of the thesis studies the behaviour of solutions to a class of doubly nonlinear degenerate parabolic problems when the data are perturbed. The class includes the Richards equation, the Stefan problem and the parabolic Leray--Lions equation. We show that, up to a subsequence, weak solutions of the perturbed problem converge uniformly-in-time to weak solutions of the original problem as the perturbed data approach the original data.
title: The total position-spread tensor
title: Spin partition
titleType: Subtitle
Creators: name: Khatib, Muammar El
name: Brea, Oriana
name: Fertitta, Edoardo
name: Bendazzoli, Gian Luigi
name: Evangelisti, Stefano
name: Leininger, Thierry
Publisher: name: Freie Universität Berlin
Year: 2015
Subjects: subject: 500 Naturwissenschaften und Mathematik::530 Physik

description: The Total Position Spread (TPS) tensor, defined as the second moment cumulant of the position operator, is a key quantity to describe the mobility of electrons in a molecule or an extended system. In the present investigation, the partition of the TPS tensor according to spin variables is derived and discussed. It is shown that, while the spin-summed TPS gives information on charge mobility, the spin-partitioned TPS tensor becomes a powerful tool that provides information about spin fluctuations. The case of the hydrogen molecule is treated, both analytically, by using a 1s Slater-type orbital, and numerically, at Full Configuration Interaction (FCI) level with a V6Z basis set. It is found that, for very large inter-nuclear distances, the partitioned tensor growths quadratically with the distance in some of the low-lying electronic states. This fact is related to the presence of entanglement in the wave function. Non-dimerized open chains described by a model Hubbard Hamiltonian and linear hydrogen chains H n (n ≥ 2), composed of equally spaced atoms, are also studied at FCI level. The hydrogen systems show the presence of marked maxima for the spin-summed TPS (corresponding to a high charge mobility) when the inter-nuclear distance is about 2 bohrs. This fact can be associated to the presence of a Mott transition occurring in this region. The spin-partitioned TPS tensor, on the other hand, has a quadratical growth at long distances, a fact that corresponds to the high spin mobility in a magnetic system.
Discrete Signal Processing on Graphs
Creators: name: Sandryhaila, Aliaksei
name: Moura, Jose M. F.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Social and Information Networks (cs.SI)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: In social settings, individuals interact through webs of relationships. Each individual is a node in a complex network (or graph) of interdependencies and generates data, lots of data. We label the data by its source, or formally stated, we index the data by the nodes of the graph. The resulting signals (data indexed by the nodes) are far removed from time or image signals indexed by well ordered time samples or pixels. DSP, discrete signal processing, provides a comprehensive, elegant, and efficient methodology to describe, represent, transform, analyze, process, or synthesize these well ordered time or image signals. This paper extends to signals on graphs DSP and its basic tenets, including filters, convolution, z-transform, impulse response, spectral representation, Fourier transform, frequency response, and illustrates DSP on graphs by classifying blogs, linear predicting and compressing data from irregularly located weather stations, or predicting behavior of customers of a mobile service provider.
Asymptotic factorization of n-particle SU(N) form factors
Creators: name: Babujian, Hrachya M.
name: Foerster, Angela
name: Karowski, Michael
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Bethe Ansatz
subject: Field Theories in Lower Dimensions
subject: Integrable Field Theories
subject: Lattice Integrable Models
subject: 500 Naturwissenschaften und Mathematik::530 Physik::530 Physik

description: We investigate the high energy behavior of the SU(N) chiral Gross-Neveu model in 1 + 1 dimensions. The model is integrable and matrix elements of several local operators (form factors) are known exactly. The form factors show rapidity space clustering, which means factorization, if a group of rapidities is shifted to infinity. We analyze this phenomenon for the SU(N) model. For several operators the factorization formulas are presented explicitly.
Investigation of the occurrence of pathological carcass alterations at the processing plant in meat turkeys reared in organic production systems in Germany
Creators: name: Freihold, Darja
name: Bartels, T.
name: Bergmann, S.
name: Berk, J.
name: Deerberg, F.
name: Dressel, A.
name: Erhard, M. H.
name: Ermakow, O.
name: Thieme, Susann
name: Hafez, Hafez Mohamed
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: organic rearing of meat turkey
subject: carcass investigation at slaughterhouse (breast skin lesion, liver alteration, swelling of the hock joint)
subject: animal welfare
subject: 600 Technik, Medizin, angewandte Wissenschaften::630 Landwirtschaft::630 Landwirtschaft und verwandte Bereiche

description: In the present study the occurrence of turkey carcass alterations such as breast skin lesions, liver lesions, and swelling of the hock joint in turkeys reared in organic farms was investigated at slaughterhouses in Germany. The examinations included 1,860 turkey carcasses of 2 turkey lines Kelly Broad Breasted Bronze(BBB) (540 toms and 540 hens) and British United Turkeys (Big 6 and The Test Product 7) (780 hens). The results showed that breast skin lesions were rare (1.7%). On the other hand, liver lesions were a common finding in both hens and toms. Nearly half of all investigated turkeys were affected (49.3%). Swelling of the hock joint was detected in 17.3% of all investigated turkeys; the occurrence in Kelly BBB toms was significantly higher than in hens (toms: 28.7%; hens: 16.9%). In general, there were significant differences between the investigated flocks. Carcass lesions are a major animal welfare concern, which affect conventional and organic reared turkeys. Investigating the occurrence of carcass lesions provides the necessary precondition to establish a benchmarking system to evaluate and compare turkey farms. The aim is to reduce and/or eliminate these alterations in the long term in order to improve animal welfare.
Models of Morning Glory as Interacting Non-Linear Waves
Creators: name: Korostil, Igor Andriy
Publisher: name: Monash University
Year: 2017
Subjects: Uncategorized

description: The research presented in this thesis is motivated by a rare phenomenon known as the Morning Glory. This is a series of roll clouds that can be observed daily in the latter months of the year in the vicinity of the Gulf of Carpentaria in Queensland, Australia. Data collected during several scientific expeditions intended to clarify the nature of the phenomenon revealed that it can behave both as an undular bore and a series of solitary waves.

 Recent high-resolution simulations of a possible Morning Glory generation mechanism, specifically, collision of two sea breezes, indicated that the phenomenon may be sufficiently well described by the resonant interaction of internal solitary waves governed by a system of coupled Korteweg de-Vries (KdV) equations. The latter were shown to emerge in the case of resonant interaction of two solitary waves with nearly equal phase speeds but belonging to different modes.

 Here, we first derive a system of coupled forced KdV equations for a fluid configuration with a bell-shaped topography. The derivation is an extension of the previously derived systems to include forcing. Then we consider two three-layer fluid configurations in order to relate the previously derived coupled equations to key physical parameters inherent to stratified fluids. One configuration has both the basic flow and density constant within each layer while the other is described by piecewise linear shear flow continuous across the unperturbed interfaces and the piecewise constant density profile. We calculate the system coefficients in terms of fluid layer heights, flow velocities and densities for various resonances.

 As it was demonstrated that the systems of the type that we obtained are typically not solvable by the inverse scattering transform and therefore have to be integrated numerically, our next step is to identify numerical methods that ensure the optimal conservation of the system invariants with respect to resource utilisation (CPU time). An extensive comparison of second and fourth order numerical methods shows that exponential integrators tend to outperform most other methods with a notable exception of the Linearly-Implicit Runge-Kutta (LIRK4) and Commutator-free fourth-order methods.

 Next we propose a numerical iteration method for computation of solitary wave solutions of the system of forced KdV equations. This algorithm, which uses the forward-backward Euler differencing, is based on the Accelerated Imaginary-Time Evolution Method (AITEM) and involves normalising the solution at each time step to preserve the momentum (power).

 Finally, we investigate instabilities of solitary wave solutions obtained using the mentioned AITEM-like method. To investigate the nonlinear evolution of instabilities the LIRK4 method is employed. We observe and describe several interesting instabilities reminiscent of the Morning Glory behaviour.

 Thesis concludes with the summary of results.
Applications of smooth lattice general relativity
Creators: name: Gabriel, Adam
Publisher: name: Monash University
Year: 2017
Subjects: Uncategorized

description: We present the numerical evolution of two spacetimes using a lattice-based formulation of the 3+1 formalism called smooth lattice general relativity, with the intention of comparing it to more conventional methods. There are several distinguishing features of this approach. We use a lattice composed of short geodesic legs to approximate spacetime. Attached to each vertex of the lattice is a Riemann normal coordinate frame, so that in a sufficiently small neighbourhood of each vertex, the metric is locally flat. A collection of transformations relates the data in adjacent frames. The dynamics are governed by evolution equations for the lattice legs, the extrinsic curvature tensor, and the Riemann curvature tensor. The first spacetime we investigated was the Gowdy spacetime with Tᶟ topology, evolving forwards in time. Using a lattice adapted to the symmetries of the system, we explicitly derived the transformation between Riemann normal coordinate frames in order to find expressions for the time derivatives of the Riemann tensor. We compared the quality of results obtained using smooth lattice general relativity to both the exact solution and a direct solution of Einstein's equations. We found that our results were consistent with the exact answer, however instabilities prevented long term evolutions. The other spacetime we looked at was the axisymmetric Brill wave spacetime in 2+1 dimensions, which has fewer symmetries than the Gowdy spacetime. As there is no exact solution, we compared our results against standard numerical techniques used in general relativity. We also demonstrated how to incorporate the cartoon method into smooth lattice general relativity, which provided a means for performing evolutions in a restricted 3+1 setting with Cartesian coordinates. Although in both cases we only managed evolutions of low amplitude waves, we again found agreement with the expected results.
Insights into Reaction Kinetics in Confined Space: Real Time Observation of Water Formation under a Silica Cover
Creators: name: Prieto, Mauricio J.
name: Mullan, Thomas
name: Schlutow, Mark
name: Gottlob, Daniel M.
name: Tănase, Liviu C.
name: Schmidt, Thomas
name: Freund, Hans-Joachim
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: water formation reaction
subject: physical confinement
subject: reaction knetics
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften

description: We offer a comprehensive approach to determine how physical confinement can affect the water formation reaction. By using free-standing crystalline SiO2 bilayer supported on Ru(0001) as a model system, we studied the water formation reaction under confinement in situ and in real time. Low-energy electron microscopy reveals that the reaction proceeds via the formation of reaction fronts propagating across the Ru(0001) surface. The Arrhenius analyses of the front velocity yield apparent activation energies (Eaapp) of 0.32 eV for the confined and 0.59 eV for the nonconfined reaction. DFT simulations indicate that the rate-determining step remains unchanged upon confinement, therefore ruling out the widely accepted transition state effect. Additionally, H2O accumulation cannot explain the change in Eaapp for the confined cases studied because its concentration remains low. Instead, numerical simulations of the proposed kinetic model suggest that the H2 adsorption process plays a decisive role in reproducing the Arrhenius plots.