cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Cluster analysis of resistance combinations in Escherichia coli from different human and animal populations in Germany 2014-2017
Creators: name: Suwono, Beneditta
name: Eckmanns, Tim
name: Kaspar, Heike
name: Merle, Roswitha
name: Zacher, Benedikt
name: Kollas, Chris
name: Weiser, Armin A.
name: Noll, Ines
name: Feig, Marcel
name: Tenhagen, Bernd-Alois
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Escherichia coli
subject: Livestock
subject: Antibiotics
subject: 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::570 Biowissenschaften; Biologie

description: Recent findings on Antibiotic Resistance (AR) have brought renewed attention to the comparison of data on AR from human and animal sectors. This is however a major challenge since the data is not harmonized. This study performs a comparative analysis of data on resistance combinations in Escherichia coli (E. coli) from different routine surveillance and monitoring systems for human and different animal populations in Germany. Data on E. coli isolates were collected between 2014 and 2017 from human clinical isolates, non-clinical animal isolates from food-producing animals and food, and clinical animal isolates from food-producing and companion animals from national routine surveillance and monitoring for AR in Germany. Sixteen possible resistance combinations to four antibiotics—ampicillin, cefotaxime, ciprofloxacin and gentamicin–for these populations were used for hierarchical clustering (Euclidian and average distance). All analyses were performed with the software R 3.5.1 (Rstudio 1.1.442). Data of 333,496 E. coli isolates and forty-one different human and animal populations were included in the cluster analysis. Three main clusters were detected. Within these three clusters, all human populations (intensive care unit (ICU), general ward and outpatient care) showed similar relative frequencies of the resistance combinations and clustered together. They demonstrated similarities with clinical isolates from different animal populations and most isolates from pigs from both non-clinical and clinical isolates. Isolates from healthy poultry demonstrated similarities in relative frequencies of resistance combinations and clustered together. However, they clustered separately from the human isolates. All isolates from different animal populations with low relative frequencies of resistance combinations clustered together. They also clustered separately from the human populations. Cluster analysis has been able to demonstrate the linkage among human isolates and isolates from various animal populations based on the resistance combinations. Further analyses based on these findings might support a better one-health approach for AR in Germany.
The spectrum and the phase transition of models solvable through the full interval method
Creators: name: Aghamohammadi, Amir
name: Khorrami, Mohammad
Publisher: name: arXiv
Year: 2012
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The most general exclusion single species reaction-diffusion models with nearest-neighbor interactions one a one dimensional lattice are investigated, for which the evolution of full intervals are closed. Using a generating function method, the probability that n consecutive sites be full is investigated. The stationary values of these probabilities, as well as the spectrum of the time translation generator (Hamiltonian) of these are obtained. It is shown that depending on the reaction rates the model could exhibit a dynamical phase transition.
Fabrication of mesoscale polymeric templates for three-dimensional disordered photonic materials
Creators: name: Haberko, Jakub
name: Scheffold, Frank
Publisher: name: arXiv
Year: 2012
Subjects: subject: Optics (physics.optics)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We report on the mesoscale fabrication and characterization of polymeric templates for isotropic photonic materials derived from hyper- uniform point patterns using direct laser writing in a polymer photoresist. We study experimentally the microscopic structure by electron microscopy and small angle light scattering. Reducing the refractive index mismatch by liquid infiltration we find good agreement between the scattering data and numerical calculations based on a discrete dipole approximation. Our work demonstrates the feasibility of fabricating such random designer materials on technologically relevant length scales.
description: submitted
Estimation of variance of the difference-cum-ratio-type exponential estimator in simple random sampling
Creators: name: Daraz, Umer
name: Khan, Mursala
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Study variable
subject: auxiliary information
subject: variance estimation
subject: minimum and maximum values
subject: bias
subject: MSE
subject: 500 Naturwissenschaften und Mathematik::510 Mathematik::510 Mathematik

description: In this article, we have suggested a class of estimators for the estimation of the population variance of the variable of interest. The proposed estimators used some certain known information of the auxiliary variable, such as kurtosis, coefficient of variation, and the minimum and maximum values. The properties of the suggested class of estimators such as the bias and mean squared error (MSE) are obtained up to the first order of approximation. In order to check the performances of the estimators and to verify the theoretical results, we conducted a simulation study. The results of the simulation study show that the proposed class of estimators have lower MSE than other existing estimators. This holds for all simulation scenarios. In the application part, we used data from Statistical Bureau of Pakistan, and from the Textbook of Cochran, which also confirms that the suggested class of estimators is more efficient than the usual unbiased variance estimator, ratio estimator, traditional regression estimator, and other existing estimators in survey literature.
Self-induced pinning of vortices in the presence of ac driving force in magnetic superconductors
Creators: name: Bulaevskii, Lev N.
name: Lin, Shi-Zeng
Publisher: name: arXiv
Year: 2012
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We derive the response of the magnetic superconductors in the vortex state to the ac Lorentz force, $F_L(t)=F_{\rm ac}\sin(ωt)$, taking into account the interaction of vortices with the magnetic moments described by the relaxation dynamics (polaronic effect). At low amplitudes of the driving force $F_{\rm ac}$ the dissipation in the system is suppressed due to the enhancement of the effective viscosity at low frequencies and due to formation of the magnetic pinning at high frequencies $ω$. In the adiabatic limit with low frequencies $ω$ and high amplitude of the driving force $F_{ac}$, the vortex and magnetic polarization form a vortex polaron when $F_L(t)$ is small. When $F_L$ increases, the vortex polaron accelerates and at a threshold driving force, the vortex polaron dissociates and the motion of vortex and the relaxation of magnetization are decoupled. When $F_L$ decreases, the vortex is retrapped by the background of remnant magnetization and they again form vortex polaron. This process repeats when $F_L(t)$ increases in the opposite direction. Remarkably, after dissociation, decoupled vortices move in the periodic potential induced by magnetization which remains for some periods of time due to retardation after the decoupling. At this stage vortices oscillate with high frequencies determined by the Lorentz force at the moment of dissociation. We derive also the creep rate of vortices and show that magnetic moments suppress creep rate.
description: 7.3 pages and 8 figures
Severe Convective Windstorms in Europe: Climatology, Preconvective Environments, and Convective Mode
Creators: name: Pacey, George P.
name: Schultz, David M.
name: Garcia-Carreras, Luis
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Convective storms
subject: Wind gusts
subject: Severe storms
subject: Wind effects
subject: Storm environments
subject: Convective lines
subject: 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie::551 Geologie, Hydrologie, Meteorologie

description: The frequency of European convective windstorms, environments in which they form, and their convective organizational modes remain largely unknown. A climatology is produced using 10 233 severe convective wind reports from the European Severe Weather Database between 2009 and 2018. Severe convective wind days have increased from 50 days yr−1 in 2009 to 117 days yr−1 in 2018, largely because of an increase in reporting. The highest frequency of reports occurred across central Europe, particularly Poland. Reporting was most frequent in summer, when a severe convective windstorm occurred every other day on average. The preconvective environment was assessed using 361 proximity soundings from 45 stations between 2006 and 2018, and a clustering technique was used to distinguish different environments from nine variables. Two environments for severe convective storms occurred: Type 1, generally low-shear–high-CAPE (convective available potential energy; mostly in the warm season) and Type 2, generally high-shear–low CAPE (mostly in the cold season). Because convective organizational mode often relates to the type of weather hazard, convective organizational mode was studied from 185 windstorms that occurred between 2013 and 2018. In Type-1 environments, the most frequent convective mode was cells, accounting for 58.5% of events, followed by linear modes (29%) and the nonlinear noncellular mode (12.5%). In Type-2 environments, the most frequent convective mode was linear modes (55%), followed by cells (36%) and the nonlinear noncellular mode (9%). Only 10% of windstorms were associated with bow echoes, a lower percentage than other studies, suggesting that forecasters should not necessarily wait to see a bow echo before issuing a warning for strong winds.
Eficiência e Estabilidade do Tratamento de Soro de Leite em ASBR Contendo Biomassa Granulada Submetido a Diferentes Estratégias de Alimentação e Otimização da Suplementação de Alcalinidade
Creators: name: Mockaitis, Gustavo
name: Ratusznei, Suzana Maria
name: Domingues Rodrigues, José Alberto
name: Zaiat, Marcelo
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 400410
subject: Wastewater treatment processes

description: No presente trabalho investigou-se o processo de tratamento anaeróbio do soro de leite, em reator com agitação e biomassa granulada, operando em batelada seqüencial, analisando a influência do aumento da carga orgânica volumétrica e verificando a necessidade de suplementação da alcalinidade por meio da adição de bicarbonato de sódio correlacionando-se com a estabilidade e eficiência do processo. Durante o desenvolvimento do projeto, foram executadas as condições experimentais cujo afluente apresentava concentrações de 500, 1000, 2000 e 4000 mgDQO.l-1, sempre suplementado com bicarbonato de sódio de maneira otimizada. Foram monitoradas a concentração de substrato no afluente e no efluente (filtrado e bruto), os valores de sólidos, alcalinidade a bicarbonato e ácidos voláteis totais. Após a determinação da suplementação otimizada, foram realizados os perfis de operação durante o ciclo, para a compreensão das rotas metabólicas e da cinética envolvidas no processo. Desta maneira, pode se concluir uma operação estável e eficiente do reator nas condições estudadas.
Effects of colored noise on Landau-Zener Transitions: Two and Three-Level Systems
Creators: name: Kenmoe, M. B.
name: Phien, H. N.
name: Kiselev, M. N.
name: Fai, L. C.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We investigate the Landau-Zener transition in two- and three- level systems subject to a classical Gaussian noise. Two complementary limits of the noise being fast and slow compared to characteristic Landau-Zener tunnel times are discussed. The analytical solution of a density matrix (Bloch) equation is given for a long time asymptotic of transition probability. It is demonstrated that the transition probability induced/assisted by the fast noise can be obtained through a procedure of {\it Bloch's equation averaging} with further reduction it to a master equation. In contrast to the case of fast noise, the transition probability for LZ transition induced/assisted by the slow classical noise can be obtained by averaging a {\it solution} of Bloch's equation over the noise realization. As a result, the transition probability is described by the activation Arrhenius law. The approximate solution of the Bloch's equation at finite times is written in terms of Fresnel's integrals and interpreted in terms of interference pattern. We discuss consequences of a local isomorphism between SU(2) and SO(3) groups and connections between Schrödinger and Bloch descriptions of spin dynamics. Based on this isomorphism we establish the relations between S=1/2 and S=1 transition probabilities influenced by the noise. A possibility to use the slow noise as a probe for tunnel time is discussed.
description: 22 pages, 8 figures
Protein-observed 19F NMR of LecA from Pseudomonas aeruginosa
Creators: name: Shanina, Elena
name: Siebs, Eike
name: Zhang, Hengxi
name: Silva, Daniel Varon
name: Joachim, Ines
name: Titz, Alexander
name: Rademacher, Christoph
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: drug discovery
subject: LecA
subject: lectin
subject: NMR
subject: 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::570 Biowissenschaften; Biologie

description: The carbohydrate-binding protein LecA (PA-IL) from Pseudomonas aeruginosa plays an important role in the formation of biofilms in chronic infections. Development of inhibitors to disrupt LecA-mediated biofilms is desired but it is limited to carbohydrate-based ligands. Moreover, discovery of drug-like ligands for LecA is challenging because of its weak affinities. Therefore, we established a protein-observed 19F (PrOF) nuclear magnetic resonance (NMR) to probe ligand binding to LecA. LecA was labeled with 5-fluoroindole to incorporate 5-fluorotryptophanes and the resonances were assigned by site-directed mutagenesis. This incorporation did not disrupt LecA preference for natural ligands, Ca2+ and d-galactose. Following NMR perturbation of W42, which is located in the carbohydrate-binding region of LecA, allowed to monitor binding of low-affinity ligands such as N-acetyl d-galactosamine (d-GalNAc, Kd = 780 ± 97 μM). Moreover, PrOF NMR titration with glycomimetic of LecA p-nitrophenyl β-d-galactoside (pNPGal, Kd = 54 ± 6 μM) demonstrated a 6-fold improved binding of d-Gal proving this approach to be valuable for ligand design in future drug discovery campaigns that aim to generate inhibitors of LecA.
Country of Words: Palestinian Literature in the Digital Age of the Refugee
Creators: name: Abu-Remaileh, Refqa
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Palestinian literature
subject: modern Arabic literature
subject: Digital Humanities
subject: literary history
subject: Edward Said
subject: Maḥmūd Darwīsh
subject: Ghassān Kanafānī
subject: Imīl Ḥabībī
subject: 800 Literatur::890 Andere Literaturen::892 Afroasiatische Literaturen, semitische Literaturen

description: The article reflects on how to embrace the unconventional, fragmented, scattered, transnational, exilic, and refugee elements of Palestinian Literature. Placing the refugees at the heart of the story of Palestinian literature raises serious questions about the compatibility of the national framework as the primary mode of analysis. The article explores the anatomy of Palestinian literature, including the wide array of sources, literary detective work, and expanded methodological toolbox needed to gather its fragments, and illustrates the potential of the digital sphere—drawing on the world of Digital Humanities—to house, express and visualize the data-fragments of Palestinian literature.
Gibbsian Method for the Self-Optimization of Cellular Networks
Creators: name: Chen, Chung Shue
name: Baccelli, Francois
Publisher: name: arXiv
Year: 2012
Subjects: subject: Optimization and Control (math.OC)
subject: Systems and Control (eess.SY)
subject: FOS: Mathematics
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: In this work, we propose and analyze a class of distributed algorithms performing the joint optimization of radio resources in heterogeneous cellular networks made of a juxtaposition of macro and small cells. Within this context, it is essential to use algorithms able to simultaneously solve the problems of channel selection, user association and power control. In such networks, the unpredictability of the cell and user patterns also requires distributed optimization schemes. The proposed method is inspired from statistical physics and based on the Gibbs sampler. It does not require the concavity/convexity, monotonicity or duality properties common to classical optimization problems. Besides, it supports discrete optimization which is especially useful to practical systems. We show that it can be implemented in a fully distributed way and nevertheless achieves system-wide optimality. We use simulation to compare this solution to today's default operational methods in terms of both throughput and energy consumption. Finally, we address concrete issues for the implementation of this solution and analyze the overhead traffic required within the framework of 3GPP and femtocell standards.
description: 25 pages, 9 figures, to appear in EURASIP Journal on Wireless Communications and Networking 2012
Development and investigation of conducting polymer electrodes for microbial fuel cells
Creators: name: Jayesh Manohar Sonawane
Publisher: name: Monash University
Year: 2018
Subjects: Uncategorized

description: In this thesis we have demonstrated the use of high-performance electrodes are the prime step in the development of MFCs. The thesis describes the synthesis of polyaniline and polypyrrole on stainless steel wool electrode, and their use to evaluate the performance of the MFCs. In comparison with SS plate-based anodes, all SS Wool based anodes gave improved power densities under similar experimental conditions by at least 70%. Also, the synthesis and use of PANi-Cu composite for the development of a cheap and efficient cathode for MFCs. The j0apparent of the PANi(25 min) cathode was 170% higher than with 0.5 mg cm-2 Pt loaded cathode. Thus, demonstrating that the CP/PANi-Cu cathode was superior to the CP/Pt cathode. Finally, the fabrication of an 18 cell MFC stack containing PANi coated SS Wool is undertaken and then explored as an anode for power generation with landfill leachate. In the current generation mode, the develop electrodes may subsequently enable the deployment of the MFC stack in real wastewater process train as a pilot plant for power generation.
Migration-Led Institutional Change in Urban Development and Planning
Creators: name: Barbarino, Robert
name: Räuchle, Charlotte
name: Scholz, Wolfgang
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: institutional change
subject: migration
subject: urban development
subject: urban governance
subject: 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie::550 Geowissenschaften

description: The migration-city-nexus has become central in migration and urban studies alike. This ‘local turn’ has not only initiated a rethinking of the local level as an independent level of migration policy-making but also broadened the discourse on how migration processes actually change cities. Therefore, the thematic issue at hand seeks to understand how migration-led development processes in cities promote and shape institutional change, and which actors transform policies, structures, and discourses on migration in different settings. It questions how migration-related issues in urban development are being handled and transformed by local state and civil society actors. With 11 empirical articles on local negotiations of migration in urban development in different settings, this thematic issue applies an institutional change perspective on local migration policy-making to contribute to a broader understanding of migration-led development in both urban and migration studies. When it comes to clearly capturing migration-led institutional change in urban development and planning, the contributions demonstrate great heterogeneity. They reveal that research on migration-led institutional change still has many biases and is very dependent on theoretical perspectives, positionalities of researchers, and the local context of the case studies.
Extraction of Bioactive Compounds fro Horticultural Processing Waste
Creators: name: Jhumur Banerjee
Publisher: name: Monash University
Year: 2018
Subjects: subject: 39901 Environmental Chemistry (incl. Atmospheric Chemistry)
subject: FOS: Chemical sciences

description: The search for sustainable resources in modern industrial processes has guided the production of chemicals and fuels towards a biomass-based economy. Biomass is a cheaper feedstock, which can even be obtained from food waste. Among such sources, the horticultural processing waste was found to contribute significantly to the overall wastage. In the current study, mango processing waste (peels and seeds) was studied in terms of the composition, recovery of bioactive compounds, utilization of the extracted bioactive compounds in product development, and the economic challenges in the overall process. Many valuable products such as pectin, polyphenols and lipids were obtained using green extraction methods, which were found to be useful in development of food grade products.
Mono- and Di-Mesoionic Carbene-Boranes: Synthesis, Structures and Utility as Reducing Agents
Creators: name: Stein, Felix
name: Kirsch, Marius
name: Beerhues, Julia
name: Albold, Uta
name: Sarkar, Biprajit
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Mesoionic carbene
subject: Triazole
subject: Triazolylidene
subject: Boranes
subject: Reduction
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften

description: Mesoionic carbenes (MIC) of the 1,2,3-triazol-5-ylidene type are currently popular ligands in organometallic chemistry. Their use in main group chemistry has been rather limited. In this contribution we present mono- and di-MIC-boranes with MICs based on triazolylidenes. The synthesis involves in-situ deprotonation of the corresponding triazolium salts and their reaction with boranes to form the desired compounds. Whereas this reaction route worked well for all triazolium salts derived from the 1,4-regioisomer of the triazoles, for the methlyene-bridged bi-triazolium salt derived from a 1,5-substiuted triazole, we observed the unexpected decomposition of the bi-triazolium and the formation of a triazole-borane with a new N−B bond. All compounds were characterized via multinuclear NMR spectroscopy, mass spectrometry, and single crystal X-ray diffraction. Furthermore, the MIC-boranes were used as reducing agents for the reduction of the C=O of aldehydes to the corresponding alcohols.
Design and Analysis of Numerical Schemes with Characteristic Methods on Generic Grids for Flows in Porous Media
Creators: name: HANZ MARTIN CHENG
Publisher: name: Monash University
Year: 2019
Subjects: subject: 10301 Numerical Analysis
subject: FOS: Mathematics
subject: 10302 Numerical Solution of Differential and Integral Equations

description: This thesis studies characteristic-based numerical schemes for a mathematical model of miscible fluid flow in porous media, a coupled and advection-dominated system of partial differential equations describing an oil recovery process. In particular, we analyse characteristic-based schemes on generic polygonal meshes, with diffusive component discretised using modern finite volume methods. We also develop a novel algorithm for reconstructing velocity fields suitable for characteristic tracking. The proposed scheme mixes two characteristic-based discretisations, and implements an original post-processing algorithm to ensure local and global mass conservation. Extensive numerical tests are provided, on various polygonal meshes. A rigorous convergence analysis is also performed.
Degradation of resolution in a homogeneous dual readout hadronic calorimeter
Creators: name: Groom, Donald E.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: If the response to a hadronic shower in a semi-infinite uniform calorimeter structure is $S$ relative to the electronic response, then $S/E = [\fem + (1-\fem)(h/e)]$, where $E$ is the incident hadron energy, $\fem$ is the electronic shower fraction, and $h/e$ is the hadron/electron response ratio. In conventional calorimeters the energy resolution is dominated by the stochastic variable $\fem$, whose broad, skewed pdf has an energy-dependent mean. The slow increase of the mean with $E$ is responsible for response nonlinearity and the skewness results in a non-Gaussian response. If the cascade is observed in two channels with different values of $h/e$ (typically scintillator($S$) and Cherenkov ($C$)), $\fem$ can be eliminated. An energy estimator, linear in $C$ and $S$, is obtained which is proportional to the incident hadron's energy. The resolution depends upon the contrast in $h/e$ between the two channels. The Cherenkov $h/e$ will be 0.20--0.25. In sampling calorimeters, $h/e$ can be increased to about 0.7 by arranging for preferential absorption of the electromagnetic (EM) shower energy in the absorber (decreasing $e$) and using a hydrogenous detector (organic scintillator) to enhance $h$ through the contribution of recoil protons in $n$--$p$ scattering. Neither mechanism is available in a homogeneous crystal or glass scintillator,\rm where $h/e$is expected to be in the vicinity of 0.4 because of invisible hadronic energy loss and other effects. The $h/e$ contrast is very likely too small to provide the needed energy resolution. We support this conclusion with simple Monte Carlo simulations.
description: 18 pages, 6 figures, submitted to NIMA
Anagram-free Graph Colouring and Colour Schemes
Creators: name: TIMOTHY EDWARD WILSON
Publisher: name: Monash University
Year: 2019
Subjects: subject: 10104 Combinatorics and Discrete Mathematics (excl. Physical Combinatorics)
subject: FOS: Mathematics

description: Graphs model the connectivity of networks, and many researchers study how to colour the nodes of a graph under various restrictions. Anagram-free colouring is a type of graph colouring which requires the first half of every path through a graph to not be a permutation of the second half. This thesis answers questions about the number of colours required to anagram-free colour many types of graphs. It also studies anagram-free colouring in a wider context by introducing colour schemes, an axiomatic approach that unifies known types of graph colouring.
Étale cohomology of rank one ℓ -adic local systems in positive characteristic
Creators: name: Esnault, Hélène
name: Kerz, Moritz
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: vanishing theorems
subject: moduli spaces
subject: conjecture
subject: 500 Naturwissenschaften und Mathematik::510 Mathematik::510 Mathematik

description: We show that in positive characteristic special loci of deformation spaces of rank one ℓ-adic local systems are quasi-linear. From this we deduce the Hard Lefschetz theorem for rank one ℓ-adic local systems and a generic vanishing theorem.
Re-gauging groupoid, symmetries and degeneracies for Graph Hamiltonians and applications to the Gyroid wire network
Creators: name: Kaufmann, Ralph M.
name: Khlebnikov, Sergei
name: Wehefritz-Kaufmann, Birgit
Publisher: name: arXiv
Year: 2012
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We study a class of graph Hamiltonians given by a type of quiver representation to which we can associate (non)--commutative geometries. By selecting gauging data these geometries are realized by matrices through an explicit construction or a Kan-extension. We describe the changes in gauge via the action of a regauging groupoid. It acts via matrices that give rise to a noncommutative 2--cocycle and hence to a groupoid extension (gerbe). We furthermore show that automorphisms of the underlying graph of the quiver can be lifted to extended symmetry groups of regaugings. In the commutative case, we deduce that the extended symmetries act via a projective representation. This yields isotypical decompositions and super--selection rules. We apply these results to the PDG and honeycomb wire--networks using representation theory for projective groups and show that all the degeneracies in the spectra are consequences of these enhanced symmetries. This includes the Dirac points of the G(yroid) and the honeycomb systems.
description: 35 pages, 4 figures, presentation improved and section on non-commutative cocycle expanded
P. C. Hartmann, Der Bayerische Reichskreis (1500–1803). Strukturen, Geschichte und Bedeutung im Rahmen der Kreisverfassung und der allgemeinen institutionellen Entwicklung des Heiligen Römischen Reiches, 1997
Creators: name: Pillorget, R.
Publisher: name: Francia
Year: 2019

description: Francia, Bd. 28 Nr. 2 (2001)
Correction: Synthesis and spectroscopic characterization of a fluorescent phenanthrene–rhodamine dyad for ratiometric measurements of acid pH values
Creators: name: Srivastava, Priyanka
name: Fürstenwerth, Paul Christian
name: Witte, Jan Felix
name: Resch-Genger, Ute
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: corrigendum
subject: spectroscopic characterization
subject: fluorescent phenanthrene-rhodamine dyad
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften

description: Correction for ‘Synthesis and spectroscopic characterization of a fluorescent phenanthrene–rhodamine dyad for ratiometric measurements of acid pH values’ by Priyanka Srivastava et al., New J. Chem., 2021, DOI: 10.1039/d1nj01573g. The authors would like to correct Fig. 6, as the spectra of dyad 8 and compound 6 recorded at 315 nm were labelled incorrectly. The corrected Fig. 6 is shown below.
Survival of the Scarcer
Creators: name: Gabel, Alan
name: Meerson, Baruch
name: Redner, S.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Populations and Evolution (q-bio.PE)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: We investigate extinction dynamics in the paradigmatic model of two competing species A and B that reproduce (A-->2A, B-->2B), self-regulate by annihilation (2A-->0, 2B-->0), and compete (A+B-->A, A+B-->B). For a finite system that is in the well-mixed limit, a quasi-stationary state arises which describes coexistence of the two species. Because of discrete noise, both species eventually become extinct in time that is exponentially long in the quasi-stationary population size. For a sizable range of asymmetries in the growth and competition rates, the paradoxical situation arises in which the numerically disadvantaged species according to the deterministic rate equations survives much longer.
description: 5 pages, 2-column revtex4-1 format; current revision has stylistic changes in response to referees, for publication in PRE Rapid Communications
Extremal Graph Theory for Minors, Improper Colourings and Gonality
Creators: name: KEVIN JOHN HENDREY
Publisher: name: Monash University
Year: 2019
Subjects: subject: 10104 Combinatorics and Discrete Mathematics (excl. Physical Combinatorics)
subject: FOS: Mathematics

description: A graph, consists of a collection of vertices, some of which are joined by edges. Graphs are extremely useful for modelling and solving a wide range of real world problems, from traffic congestion to scheduling problems. We answer several questions about abstract graphs. We show that if a graph has five times as many edges as vertices, then it contains a structure known as a Petersen Minor, and present a formula for generating bounds of this form. We also find new results for variants of vertex colourings, and answer three recently posed questions about a chip firing game on graphs.
Potentiality of Graphene Oxide and Polyoxometalate as Radionuclides Adsorbent to Restore the Environment after Fukushima Disaster: A Mini Review
Creators: name: Nugroho, Bangun Satrio
name: Wihadi, Muh Nur Khoiru
name: Grote, Fabian
name: Eigler, Siegfried
name: Nakashima, Satoru
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: adsorbent
subject: Fukushima disaster
subject: graphene oxide
subject: polyoxometalates
subject: radionuclides
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften

description: This paper discusses the promising candidate of excellent materials, graphene oxide (GO) and polyoxometalates (POMs), for radionuclide adsorbent. In this perspective, the unique properties of GO and POMs make them ideal candidates for developing new composites having the ability to adsorb radionuclides, and several essential things are reviewed. First, the anchoring mechanism to deposit POM on the GO surface area by (i) carboxylation method, (ii) covalent bonding, and (iii) impregnation method. Second, the radionuclides removal mechanism is described in several systems: (i) coagulation, (ii) electrostatic interaction, (iii) ion trapping, and (iv) H+-exchange. Third, the experimental condition that employed to enlarge the sorption capacity such as (i) pH adjustment, (ii) employing multiple oxidations, and (iii) cation charge. A thorough understanding of the POM-anchored GO material can pave the way for future research on similar materials. It can also help in understanding the nature of the interactive collaboration present between GO and POM.
Cyclic tensile tests of Shetland pony superficial digital flexor tendons (SDFTs) with an optimized cryo-clamp combined with biplanar high-speed fluoroscopy
Creators: name: Wagner, Franziska C.
name: Reese, Sven
name: Gerlach, Kerstin
name: Böttcher, Peter
name: Mülling, Christoph K. W.
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Equine
subject: Horse
subject: Superficial digital flexor tendon (SDFT)
subject: Cryo-clamp
subject: Strain
subject: XROMM
subject: 600 Technik, Medizin, angewandte Wissenschaften::630 Landwirtschaft::630 Landwirtschaft und verwandte Bereiche

description: Background Long-term cyclic tensile testing with equine palmar/plantar tendons have not yet been performed due to problems in fixing equine tendons securely and loading them cyclically. It is well established that the biomechanical response of tendons varies during cyclic loading over time. The aim of this study was to develop a clamping device that enables repetitive cyclic tensile testing of equine superficial digital flexor tendon for at least 60 loading cycles and for 5 min. Results A novel cryo-clamp was developed and built. Healthy and collagenase-treated pony SDFTs were mounted in the custom-made cryo-clamp for the proximal tendon end and a special clamping device for the short pastern bone (os coronale). Simultaneously with tensile testing, we used a biplanar high-speed fluoroscopy system (FluoKin) to track tendon movement. The FluoKin system was additionally validated in precision measurements. During the cyclic tensile tests of the SDFTs, the average maximal force measured was 325 N and 953 N for a length variation of 2 and 4 % respectively. The resulting stress averaged 16 MPa and 48 MPa respectively, while the modulus of elasticity was 828 MPa and 1212 MPa respectively. Length variation of the metacarpal region was, on average, 4.87 % higher after incubation with collagenase. The precision of the FluoKin tracking was 0.0377 mm, defined as the standard deviation of pairwise intermarker distances embedded in rigid bodies. The systems accuracy was 0.0287 mm, which is the difference between the machined and mean measured distance. Conclusion In this study, a good performing clamping technique for equine tendons under repetitive cyclic loading conditions is described. The presented cryo-clamps were tested up to 50 min duration and up to the machine maximal capacity of 10 kN. With the possibility of repetitive loading a stabilization of the time-force-curve and changes of hysteresis and creep became obvious after a dozen cycles, which underlines the necessity of repetitive cyclical testing. Furthermore, biplanar high-speed fluoroscopy seems an appropriate and highly precise measurement tool for analysis of tendon behaviour under repetitive load in equine SDFTs.
Spectroscopic Investigation of the Solar Atmosphere
Creators: name: DANIELA ADRIANA LACATUS
Publisher: name: Monash University
Year: 2019
Subjects: subject: 10299 Applied Mathematics not elsewhere classified
subject: FOS: Mathematics
subject: 20109 Space and Solar Physics
subject: FOS: Physical sciences

description: Spectroscopic observations allow for detailed interpretation of the processes that govern the Sun. We establish a statistical baseline of activity by analysing quiet Sun conditions. We investigate the propagation of the energy released by solar eruptions across all layers of the solar atmosphere. An intriguing sunquake is detected. Mathematical methods are utilised to uncover the nature of peculiar manifestations in the aftermath of an eruption, discovering a highly turbulent coronal rain. We aim at understanding solar eruptions, the most energetic events in our corner of the Universe, as they are paramount for the improvement of current models of solar and stellar processes.
Reacting, fast and slow: how world leaders shaped government responses to the COVID-19 pandemic
Creators: name: Forster, Timon
name: Heinzel, Mirko
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: crisis
subject: leadership
subject: expertise
subject: COVID-19
subject: policy-making
subject: public health
subject: 300 Sozialwissenschaften::320 Politikwissenschaft::320 Politikwissenschaft

description: The COVID-19 pandemic created extraordinary challenges for governments to safeguard the well-being of their people. To what extent has leaders’ reliance on scientific advice shaped government responses to the COVID-19 outbreak? We argue that leaders who tend to orient themselves on expert advice realized the extent of the crisis earlier. Consequently, these governments would adopt containment measures relatively quickly, despite the high uncertainty they faced. Over time, differences in government responses based on the use of science would dissipate due to herding effects. We test our argument on data combining 163 government responses to the pandemic with national- and individual-level characteristics. Consistent with our argument, we find that countries governed by politicians with a stronger technocratic mentality, approximated by holding a PhD, adopted restrictive containment measures faster in the early, but not in the later, stages of the crisis. This importance of expert-based leadership plausibly extends to other large-scale societal crises.
High-Spin Iron(VI), Low-Spin Ruthenium(VI), and Magnetically Bistable Osmium(VI) in Molecular Group 8 Nitrido Trifluorides NMF3
Creators: name: Stüker, Tony
name: Xia, Xiya
name: Beckers, Helmut
name: Riedel, Sebastian
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: ab initio calculations
subject: high oxidation states
subject: matrix isolation
subject: N ligands
subject: transition metals
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften

description: Pseudo-tetrahedral nitrido trifluorides N≡MF3 (M=Fe, Ru, Os) and square pyramidal nitrido tetrafluorides N≡MF4 (M=Ru, Os) were formed by free-metal-atom reactions with NF3 and subsequently isolated in solid neon at 5 K. Their IR spectra were recorded and analyzed aided by quantum-chemical calculations. For a d2 electron configuration of the N≡MF3 compounds in C3v symmetry, Hund's rule predict a high-spin 3A2 ground state with two parallel spin electrons and two degenerate metal d(δ)-orbitals. The corresponding high-spin 3A2 ground state was, however, only found for N≡FeF3, the first experimentally verified neutral nitrido FeVI species. The valence-isoelectronic N≡RuF3 and N≡OsF3 adopt different angular distorted singlet structures. For N≡RuF3, the triplet 3A2 state is only 5 kJ mol−1 higher in energy than the singlet 1A′ ground state, and the magnetically bistable molecular N≡OsF3 with two distorted near degenerate 1A′ and 3A“ electronic states were experimentally detected at 5 K in solid neon.
Comparison of Four Different Allergy Tests in Equine Asthma Affected Horses and Allergen Inhalation Provocation Test
Creators: name: Klier, John
name: Lindner, Daniela
name: Reese, Sven
name: Mueller, Ralf S.
name: Gehlen, Heidrun
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Horse
subject: Equine asthma
subject: Allergy test
subject: Histamine
subject: Immune reaction
subject: 600 Technik, Medizin, angewandte Wissenschaften::630 Landwirtschaft::630 Landwirtschaft und verwandte Bereiche

description: Potential triggers for equine asthma are allergens from hay and straw dusts, mold spores and storage mites. The contribution of these environmental trigger factors to equine asthma is still largely uncertain. The aim of this study was to compare results of four allergy tests from healthy and asthma-affected horses, and to evaluate the clinical relevance of allergens tested positive via specific inhalation provocation test. Fifteen horses were classified using a clinical scoring system as asthmatic (n = 9) or control (n = 6). Four different allergy tests (functional in vitro test, intradermal test, Fc-epsilon receptor test, and ELISA for allergen-specific IgE) were compared. A histamine inhalation provocation test as positive control was performed in all horses and the interpleural pressure was measured. In addition, two individual allergens were chosen for the allergen inhalation provocation test based on the results of the allergy tests and inhaled in increasing concentrations, until signs of dyspnea occurred. None of the four allergy tests could differentiate reliably between controls and asthma-affected horses. There was no agreement among the results of the four allergy tests. The interpleural pressure results showed a large individual variability. A clear positive reaction on the allergen inhalation provocation test was only detected in two asthma-affected horses 6 hours after allergen inhalation with Aspergillus fumigatus and Cladosporium herbarum. In most cases a purely type I immediate reaction is unlikely to be involved in causing the clinical signs of equine asthma. Because of a delayed reaction after allergen provocation in two horses, the involvement of cell-mediated type III or IV hypersensitivity may be possible. As all allergy tests used in this study can only detect IgE-mediated hypersensitivity, these tests are probably not suitable for an etiological diagnosis of equine asthma.
A novel numerical solver for nonlinear boundary value problems, with applications to the forced Gardner equation
Creators: name: ANDREW CRAIG CULLEN
Publisher: name: Monash University
Year: 2019
Subjects: subject: 40403 Geophysical Fluid Dynamics
subject: FOS: Earth and related environmental sciences
subject: 10301 Numerical Analysis
subject: FOS: Mathematics
subject: 10109 Ordinary Differential Equations, Difference Equations and Dynamical Systems
subject: Computational Physics
subject: Atmospheric Sciences
subject: Applied Computer Science
subject: Computation Theory and Mathematics
subject: FOS: Computer and information sciences
subject: 91504 Fluidisation and Fluid Mechanics
subject: FOS: Other engineering and technologies
subject: 80110 Simulation and Modelling
subject: 10299 Applied Mathematics not elsewhere classified
subject: 10302 Numerical Solution of Differential and Integral Equations
subject: 10399 Numerical and Computational Mathematics not elsewhere classified
subject: 80201 Analysis of Algorithms and Complexity
subject: 80205 Numerical Computation
subject: 20303 Fluid Physics
subject: FOS: Physical sciences

description: Nonlinear differential equations appear within a wide range of fields, however, solving these problems is particularly difficult. This work charts the development of a suite of new, numerical tools for solving nonlinear differential equations. These tools significantly outperform currently existing methods, in both the amount of time required to solve the problems, and the range of problems that can be approached. After analysing the properties of these tools, they are applied to the forced Gardner equation. This problem arises in geophysical fluid dynamics, and has particular implications to climate change and extreme weather events.
Finite-size effects in high dimensional physical systems
Creators: name: JENS CHRISTIAN GRIMM
Publisher: name: Monash University
Year: 2019
Subjects: subject: 10506 Statistical Mechanics, Physical Combinatorics and Mathematical Aspects of Condensed Matter
subject: FOS: Mathematics
subject: 10599 Mathematical Physics not elsewhere classified
subject: 10399 Numerical and Computational Mathematics not elsewhere classified

description: Statistical mechanics is a branch of mathematical physics which seeks to explain how macroscopic behaviour can emerge from the interactions between a large number of microscopic particles. One of the main aims in this field is to understand how phenomena such as phase transitions emerge in large but finite systems of interacting particles. In this thesis, we clarify a number of open questions in a long-standing debate regarding the surprising role of boundary effects in high-dimensional systems of critical phenomena.
Designing real-world laboratories for sustainable urban transformation: addressing ambiguous roles and expectations in transdisciplinary teams
Creators: name: Huning, Sandra
name: Räuchle, Charlotte
name: Fuchs, M.
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Transdisciplinary research
subject: Urban transformation
subject: Real-world laboratory
subject: Participatory research
subject: Sustainable transformation
subject: Team development
subject: 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie::550 Geowissenschaften

description: This paper reflects upon the potential of real-world laboratories (RWLs) to promote sustainable urban development. RWLs strive for knowledge production through collective action in experimental settings. Their implementation in urban studies faces two major challenges: (1) the ambiguity of roles university researchers need to fill, and (2) the variety of expectations among team members from different institutional backgrounds. Based on research in one trans-European and three German RWLs, we propose a stronger focus on team development to help researchers in RWLs address these challenges more systematically. In particular, this means support in terms of resources and infrastructure (time, space, and training). We argue that the improvement of RWL team performance has great impact on the potentials of RWLs in transformative urban studies. Thus, the article contributes to the ongoing debate on the city as a laboratory and site of experimentation in times of multiple crises.