cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Helical cosmological magnetic fields from extra-dimensions
Creators: name: Atmjeet, Kumar
name: Seshadri, T. R.
name: Subramanian, Kandaswamy
Publisher: name: arXiv
Year: 2014
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We study the inflationary generation of helical cosmological magnetic fields in a higher-dimensional generalization of the electromagnetic theory. For this purpose, we also include a parity breaking piece to the electromagnetic action. The evolution of extra-dimensional scale factor allows the breaking of conformal invariance of the effective electromagnetic action in $1+3$ dimensions required for such generation. Analytical solutions for the vector potential can be obtained in terms of Coulomb wave-functions for some special cases. We also present numerical solutions for the vector potential evolution in more general cases. In the presence of a higher-dimensional cosmological constant there exist solutions for the scale factors in which both normal and extra dimensional space either inflate or deflate simultaneously with the same rate. In such a scenario, with the number of extra dimensions $D=4$, a scale invariant spectrum of helical magnetic field is obtained. The net helicity arises, as one helical mode comes to dominate over the other at the superhorizon scales. A magnetic field strength of the order of $10^{-9}$ $G$ can be obtained for the inflationary scale $H\simeq 10^{-3}$ $M_{pl}$. Weaker fields will be generated for lower scales of inflation. Magnetic fields generated in this model respects the bounds on magnetic fields by Planck and $γ$-ray observations (i.e. $10^{-16}$ $G$ $
description: 4 postscript figures, version submitted to Physical Review D
Quantitative trait analysis in sequencing studies under trait-dependent sampling
Creators: name: Tang, Z.-Z.
name: Zeng, D.
name: Lin, D.-Y.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: It is not economically feasible to sequence all study subjects in a large cohort. A cost-effective strategy is to sequence only the subjects with the extreme values of a quantitative trait. In the National Heart, Lung, and Blood Institute Exome Sequencing Project, subjects with the highest or lowest values of body mass index, LDL, or blood pressure were selected for whole-exome sequencing. Failure to account for such trait-dependent sampling can cause severe inflation of type I error and substantial loss of power in quantitative trait analysis, especially when combining results from multiple studies with different selection criteria. We present valid and efficient statistical methods for association analysis of sequencing data under trait-dependent sampling. We pay special attention to gene-based analysis of rare variants. Our methods can be used to perform quantitative trait analysis not only for the trait that is used to select subjects for sequencing but for any other traits that are measured. For a particular trait of interest, our approach properly combines the association results from all studies with measurements of that trait. This meta-analysis is substantially more powerful than the analysis of any single study. By contrast, meta-analysis of standard linear regression results (ignoring trait-dependent sampling) can be less powerful than the analysis of a single study. The advantages of the proposed methods are demonstrated through simulation studies and the National Heart, Lung, and Blood Institute Exome Sequencing Project data. The methods are applicable to other types of genetic association studies and nongenetic studies.
Solution of moving-boundary problems by the spectral element method
Creators: name: Bodard, Nicolas
name: Bouffanais, Roland
name: Deville, Michel O.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: Numerical Analysis (math.NA)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: This paper describes a novel numerical model aiming at solving moving-boundary problems such as free-surface flows or fluid-structure interaction. This model uses a moving-grid technique to solve the Navier--Stokes equations expressed in the arbitrary Lagrangian--Eulerian kinematics. The discretization in space is based on the spectral element method. The coupling of the fluid equations and the moving-grid equations is essentially done through the conditions on the moving boundaries. Two- and three-dimensional simulations are presented: translation and rotation of a cylinder in a fluid, and large-amplitude sloshing in a rectangular tank. The accuracy and robustness of the present numerical model is studied and discussed.
description: Applied Numerical Mathematics, In Press, 2008
Nonequilibrium Electron Interactions in Metal Films
Creators: name: Del Fatti, Natalia
name: Bouffanais, Roland
name: Vallée, Fabrice
name: Flytzanis, Christos
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Ultrafast relaxation dynamics of an athermal electron distribution is investigated in silver films using a femtosecond pump-probe technique with 18 fs pulses in off-resonant conditions. The results yield evidence for an increase with time of the electron-gas energy loss rate to the lattice and of the free electron damping during the early stages of the electron-gas thermalization. These effects are attributed to transient alterations of the electron average scattering processes due to the athermal nature of the electron gas, in agreement with numerical simulations.
Effect of turbulence on electron cyclotron current drive and heating in ITER
Creators: name: Casson, F. J.
name: Poli, E.
name: Angioni, C.
name: Buchholz, R.
name: Peeters, A. G.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Non-linear local electromagnetic gyrokinetic turbulence simulations of the ITER standard scenario H-mode are presented for the q=3/2 and q=2 surfaces. The turbulent transport is examined in regions of velocity space characteristic of electrons heated by electron cyclotron waves. Electromagnetic fluctuations and sub-dominant micro-tearing modes are found to contribute significantly to the transport of the accelerated electrons, even though they have only a small impact on the transport of the bulk species. The particle diffusivity for resonant passing electrons is found to be less than 0.15 m^2/s, and their heat conductivity is found to be less than 2 m^2/s. Implications for the broadening of the current drive and energy deposition in ITER are discussed.
description: Letter, 5 pages, 5 figures, for submission to Nuclear Fusion
Transitional cylindrical swirling flow in presence of a flat free surface
Creators: name: Bouffanais, Roland
name: Jacono, David Lo
Publisher: name: arXiv
Year: 2009
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: This article is devoted to the study of an incompressible viscous flow of a fluid partly enclosed in a cylindrical container with an open top surface and driven by the constant rotation of the bottom wall. Such type of flows belongs to a group of recirculating lid-driven cavity flows with geometrical axisymmetry and of the prescribed boundary conditions of Dirichlet type -- no-slip on the cavity walls. The top surface of the cylindrical cavity is left open with an imposed stress-free boundary condition, while a no-slip condition with a prescribed rotational velocity is imposed on the bottom wall. The Reynolds regime corresponds to transitional flows with some incursions in the fully laminar regime. The approach taken here revealed new flow states that were investigated based on a fully three-dimensional solution of the Navier--Stokes equations for the free-surface cylindrical swirling flow, without resorting to any symmetry property unlike all other results available in the literature. Theses solutions are obtained through direct numerical simulations based on a Legendre spectral element method.
description: Computers and Fluids, In Press
Finding the $0^{--}$ Glueball
Creators: name: Qiao, Cong-Feng
name: Tang, Liang
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: With appropriate interpolating currents the mass spectrum of $0^{--}$ oddball is obtained in the framework of QCD Sum Rules (QCDSR). We find there are two stable oddballs with masses of $3.81 \pm 0.12 \, \text{GeV}$ and $4.33 \pm 0.13 \, \text{GeV}$, and analyze their possible production and decay modes in experiments. Noticing that these $0^{--}$ oddballs with unconventional quantum number are attainable in BESIII, BELLEII, PANDA, Super-B and LHCb experiments, we believe the long search elusive glueball could be measured shortly.
description: 5 pages, 4 figures, 1 table, to appear in Phys. Rev. Lett
Regional Measures of Sexual Orientation Bias Predict Where Same-Gender Couples Live
Creators: name: Snyder, Jason
name: PJ Henry
Publisher: name: Open Science Framework
Year: 2023
Subjects: subject: Cognitive Psychology
subject: Social Psychology
subject: Psychology
subject: FOS: Psychology
subject: Social and Behavioral Sciences

description: Data and analysis code for the paper "Regional Measures of Sexual Orientation Bias Predict Where Same-Gender Couples Live." The files to reproduce the analyses that we report in the manuscript are "OSF-IAT-samegender-couples-REVISION-final-v2_2023.02.17.rmd" and "FINAL_OSF_sexualityIAT_2023.01.10.csv" in the "analysis-script-and-data" folder below.
Variational integration for ideal magnetohydrodynamics with built-in advection equations
Creators: name: Zhou, Yao
name: Qin, Hong
name: Burby, J. W.
name: Bhattacharjee, A.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Computational Physics (physics.comp-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Newcomb's Lagrangian for ideal magnetohydrodynamics (MHD) in Lagrangian labeling is discretized using discrete exterior calculus. Variational integrators for ideal MHD are derived thereafter. Besides being symplectic and momentum-preserving, the schemes inherit built-in advection equations from Newcomb's formulation, and therefore avoid solving them and the accompanying error and dissipation. We implement the method in 2D and show that numerical reconnection does not take place when singular current sheets are present. We then apply it to studying the dynamics of the ideal coalescence instability with multiple islands. The relaxed equilibrium state with embedded current sheets is obtained numerically.
Ramshackle (Brwd3) promotes light-induced ubiquitylation of Drosophila Cryptochrome by DDB1-CUL4-ROC1 E3 ligase complex
Creators: name: Akileswaran, L.
name: VanVickle-Chavez, S. J.
name: Ozturk, N.
name: Van Gelder, R. N.
name: Sancar, A.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Cryptochrome (CRY) is the primary circadian photoreceptor in Drosophila. It resets the circadian clock by promoting light-induced degradation of the clock proteins Timeless and Period, as well as its own proteolysis. The E3 ligases that ubiquitylate Timeless and Period before degradation are known and it is known that Drosophila (d) CRY is degraded by the ubiquitin-proteasome system as well. To identify the E3 ligase for dCRY we screened candidates in S2 cells by RNAi. Knockdown of each of the 25 putative F-box proteins identified by bioinformatics did not attenuate the light-induced degradation of dCRY. However, knockdown of a WD40 protein, Bromodomain and WD repeat domain containing 3 (Brwd3) (CG31132/Ramshackle) caused strong attenuation of dCRY degradation following light exposure. We found that BRWD3 functions as a Damage-specific DNA binding protein 1 (DDB1)- and CULLIN (CUL)4-associated factor in a Cullin4-RING Finger E3 Ligase (CRL4) that mediates light-dependent binding of dCRY to CUL4-ROC1-DDB1-BRWD3, inducing ubiquitylation of dCRY and its light-induced degradation. Thus, this study identifies a light-activated E3 ligase complex essential for light-mediated CRY degradation in Drosophila cells.
Rational design of a ligand-controlled protein conformational switch
Creators: name: Shirvanyants, D.
name: Freisinger, C. M.
name: Huttenlocher, A.
name: Ding, F.
name: Dagliyan, O.
name: Dokholyan, N. V.
name: Fee, L.
name: Karginov, A. V.
name: Smolen, G. A.
name: Hahn, K. M.
name: Chandrasekaran, S. N.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Design of a regulatable multistate protein is a challenge for protein engineering. Here we design a protein with a unique topology, called uniRapR, whose conformation is controlled by the binding of a small molecule. We confirm switching and control ability of uniRapR in silico, in vitro, and in vivo. As a proof of concept, uniRapR is used as an artificial regulatory domain to control activity of kinases. By activating Src kinase using uniRapR in single cells and whole organism, we observe two unique phenotypes consistent with its role in metastasis. Activation of Src kinase leads to rapid induction of protrusion with polarized spreading in HeLa cells, and morphological changes with loss of cell–cell contacts in the epidermal tissue of zebrafish. The rational creation of uniRapR exemplifies the strength of computational protein design, and offers a powerful means for targeted activation of many pathways to study signaling in living organisms.
Galactic globular cluster 47 Tucanae: new ties between the chemical and dynamical evolution of globular clusters?
Creators: name: Kucinskas, A.
name: Dobrovolskas, V.
name: Bonifacio, P.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: It is generally accepted today that Galactic globular clusters (GGCs) consist of at least two generations of stars that are different in their chemical composition and perhaps age. However, knowledge about the kinematical properties of these stellar generations, which may provide important information for constraining evolutionary scenarios of the GGCs, is still limited. We therefore study the connections between chemical and kinematical properties of different stellar generations in the Galactic globular cluster 47 Tuc. To achieve this goal, we used abundances of Li, O, and Na determined in 101 main sequence turn-off (TO) stars with the aid of 3D hydrodynamical model atmospheres and NLTE abundance analysis methodology. We divided our sample TO stars into three groups according to their position in the [Li/Na]-[Na/O] plane to study their spatial distribution and kinematical properties. We find that there are statistically significant radial dependencies of lithium and oxygen abundances, A(Li) and A(O), as well as that of [Li/Na] abundance ratio. Our results show that first-generation stars are less centrally concentrated and dynamically hotter than stars belonging to subsequent generations. We also find a significant correlation between the velocity dispersion and O and Na abundance, and between the velocity dispersion and the [Na/O] abundance ratio.
description: 4 pages, 6 figures, accepted for publication in A&A
An improved computer vision method for detecting white blood cells
Creators: name: Cuevas, Erik
name: Diaz, Margarita
name: Manzanares, Miguel
name: Zaldivar, Daniel
name: Perez, Marco
Publisher: name: arXiv
Year: 2014
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: The automatic detection of White Blood Cells (WBC) still remains as an unsolved issue in medical imaging. The analysis of WBC images has engaged researchers from fields of medicine and computer vision alike. Since WBC can be approximated by an ellipsoid form, an ellipse detector algorithm may be successfully applied in order to recognize them. This paper presents an algorithm for the automatic detection of WBC embedded into complicated and cluttered smear images that considers the complete process as a multi-ellipse detection problem. The approach, based on the Differential Evolution (DE) algorithm, transforms the detection task into an optimization problem where individuals emulate candidate ellipses. An objective function evaluates if such candidate ellipses are really present in the edge image of the smear. Guided by the values of such function, the set of encoded candidate ellipses (individuals) are evolved using the DE algorithm so that they can fit into the WBC enclosed within the edge-only map of the image. Experimental results from white blood cell images with a varying range of complexity are included to validate the efficiency of the proposed technique in terms of accuracy and robustness.
description: 20 Pages. arXiv admin note: text overlap with arXiv:1405.5164
Simple and collective twisted symmetries
Creators: name: Gaeta, Giuseppe
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mathematical Physics (math-ph)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences

description: After the introduction of $λ$-symmetries by Muriel and Romero, several other types of so called "twisted symmetries" have been considered in the literature (their name refers to the fact they are defined through a deformation of the familiar prolongation operation); they are as useful as standard symmetries for what concerns symmetry reduction of ODEs or determination of special (invariant) solutions for PDEs and have thus attracted attention. The geometrical relation of twisted symmetries to standard ones has already been noted: for some type of twisted symmetries (in particular, $λ$ and $μ$-symmetries), this amounts to a certain kind of gauge transformation. In a previous review paper [G. Gaeta, "Twisted symmetries of differential equations", {\it J. Nonlin. Math. Phys.}, {\bf 16-S} (2009), 107-136] we have surveyed the first part of the developments of this theory; in the present paper we review recent developments. In particular, we provide a unifying geometrical description of the different types of twisted symmetries; this is based on the classical Frobenius reduction applied to distribution generated by Lie-point (local) symmetries.
description: 40 pages; to appear in J. Nonlin. Math. Phys. 21 (2014), 593-627
Reconstitution of long and short patch mismatch repair reactions using Saccharomyces cerevisiae proteins
Creators: name: Griffith, J. D.
name: Bowen, N.
name: Willcox, S.
name: Srivatsan, A.
name: Kolodner, R. D.
name: Smith, C. E.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: This study demonstrates mismatch repair (MMR) reactions reconstituted in vitro with purified Saccharomyces cerevisiae proteins. Biochemical analysis of MMR in vitro showed that MMR required mispair binding by the MutS homolog 2–MutS homolog 6 complex and corresponded to the Exonuclease 1-dependent subpathway of MMR. The reactions observed involved the formation of long excision tracts whose length was consistent with the length of MMR-dependent gene conversion tracts in vivo. The availability of this reconstituted MMR reaction now allows the wealth of mutations affecting MMR generated from the genetic analysis of S. cerevisiae MMR mechanisms in vivo to be used in biochemical reconstitution studies whose ultimate goal is to reconstitute MMR linked to both DNA replication and recombination.
Cocycle Rigidity and Splitting for some Discrete Parabolic Actions
Creators: name: Damjanovic, Danijela
name: Tanis, James
Publisher: name: arXiv
Year: 2014
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 37A17, 37A20

description: We prove trivialization of the first cohomology with coefficients in smooth vector fields, for a class of $\mathbb Z^2$ parabolic actions on $(SL(2, \mathbb R)\times SL(2, \mathbb R))/Γ$, where the lattice $Γ$ is irreducible and co-compact. We also obtain a splitting construction involving first and second coboundary operators in the cohomology with coefficients in smooth vector fields.
description: 21 pages
SCFKMD controls cytokinin signaling by regulating the degradation of type-B response regulators
Creators: name: Kieber, J. J.
name: Kim, H. J.
name: Schaller, G. E.
name: Chiang, Y.-H.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Cytokinins are plant hormones that play critical roles in growth and development. In Arabidopsis, the transcriptional response to cytokinin is regulated by action of type-B Arabidopsis response regulators (ARRs). Although central elements in the cytokinin signal transduction pathway have been identified, mechanisms controlling output remain to be elucidated. Here we demonstrate that a family of F-box proteins, called the KISS ME DEADLY (KMD) family, targets type-B ARR proteins for degradation. KMD proteins form an S-PHASE KINASE-ASSOCIATED PROTEIN1 (SKP1)/Cullin/F-box protein (SCF) E3 ubiquitin ligase complex and directly interact with type-B ARR proteins. Loss-of-function KMD mutants stabilize type-B ARRs and exhibit an enhanced cytokinin response. In contrast, plants with elevated KMD expression destabilize type-B ARR proteins leading to cytokinin insensitivity. Our results support a model in which an SCFKMD complex negatively regulates cytokinin responses by controlling levels of a key family of transcription factors.
Physical limits on cellular directional mechanosensing
Creators: name: Bouffanais, Roland
name: Sun, Jianmin
name: Yue, Dick K. P.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Quantitative Methods (q-bio.QM)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: Many eukaryotic cells are able to perform directional mechanosensing by directly measuring minute spatial differences in the mechanical stress on their membranes. Here, we explore the limits of a single mechanosensitive channel activation using a two-state double-well model for the gating mechanism. We then focus on the physical limits of directional mechanosensing by a single cell having multiple mechanosensors and subjected to a shear flow inducing a nonuniform membrane tension. Our results demonstrate that the accuracy in sensing the mechanostimulus direction not only increases with cell size and exposure to a signal, but also grows for cells with a near-critical membrane prestress. Finally, the existence of a nonlinear threshold effect, fundamentally limiting the cell's ability to effectively perform directional mechanosensing at a low signal-to-noise ratio, is uncovered.
A note on four-point correlators of half-BPS operators in N=4 SYM
Creators: name: Chicherin, Dmitry
name: Sokatchev, Emery
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We calculate the four-point correlation function of half-BPS operators with weights 2, 3, 3, 4 in N=4 SYM to two-loop order. The OPE of this correlation function provides a nontrivial check of the integrability conjecture for a class of three-point functions formulated in arXiv:1311.6404. Our perturbative calculation exploits the supergraph formalism in N=2 harmonic superspace.
description: 13 pages, 4 figures
Stress and Social Support in Student-Athletes
Creators: name: Chin, Brian
Publisher: name: Open Science Framework
Year: 2023
Subjects: subject: Sports Sciences
subject: Mental and Social Health
subject: Medicine and Health Sciences

description: This survey study aims to examine the sources of stress and support for student-athletes at Trinity College. Participants will be asked to complete self-report questionnaires assessing their perceptions of psychological stress and support. We will examine the role of social support in student-athletes’ lives, test whether student-athletes’ stress and social support are associated with their mental health, and attempt to identify tools to help athletes succeed on and off the field.
Controllability of a swarm of topologically interacting autonomous agents
Creators: name: Komareji, Mohammad
name: Bouffanais, Roland
Publisher: name: arXiv
Year: 2014
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences
subject: 2000: 82C22, 94C15, 05C40

description: Controllability of complex networks has been the focal point of many recent studies in the field of complexity. These landmark advances shed a new light on the dynamics of natural and technological complex systems. Here, we analyze the controllability of a swarm of autonomous self-propelled agents having a topological neighborhood of interactions, applying the analytical tools developed for the study of the controllability of arbitrary complex directed networks. To this aim we thoroughly investigate the structural properties of the swarm signaling network which is the information transfer channel underpinning the dynamics of agents in the physical space. Our results show that with 6 or 7 topological neighbors, every agent not only affects, but is also affected by all other agents within the group. More importantly, still with 6 or 7 topological neighbors, each agent is capable of full control over all other agents. This finding is yet another argument justifying the particular value of the number of topological neighbors observed in field observations with flocks of starlings.
description: 9 pages, 3 figures. arXiv admin note: text overlap with arXiv:1401.2598
N=2 SUSY Abelian Higgs model with hidden sector and BPS equations
Creators: name: Arias, Paola
name: Ireson, Edwin
name: Núñez, Carlos
name: Schaposnik, Fidel
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this paper we study a system inspired on certain SUSY breaking models and on more recent Dark Matter scenarios. In our set-up, two Abelian gauge fields interact via an operator that mixes their kinetic terms. We find the extended Supersymmetric version of this system, that also generates a Higgs portal type of interaction. We obtain and study both analytically and numerically, the equations defining topologically stable string-like objects. We check our results using two different approaches. Various technical details are explicitly stated for the benefit of various readers.
description: 22 pages, 4 figures, 1 appendix
Solar water splitting in a molecular photoelectrochemical cell
Creators: name: Losego, M. D.
name: Song, W.
name: Meyer, T. J.
name: Parsons, G. N.
name: Alibabaei, L.
name: Brennaman, M. K.
name: Norris, M. R.
name: Binstead, R. A.
name: Kalanyan, B.
name: Concepcion, J. J.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Solar water splitting into H2 and O2 with visible light has been achieved by a molecular assembly. The dye sensitized photoelectrosynthesis cell configuration combined with core–shell structures with a thin layer of TiO2 on transparent, nanostructured transparent conducting oxides (TCO), with the outer TiO2 shell formed by atomic layer deposition. In this configuration, excitation and injection occur rapidly and efficiently with the injected electrons collected by the nanostructured TCO on the nanosecond timescale where they are collected by the planar conductive electrode and transmitted to the cathode for H2 production. This allows multiple oxidative equivalents to accumulate at a remote catalyst where water oxidation catalysis occurs.
Combining human and machine learning for morphological analysis of galaxy images
Creators: name: Kuminski, Evan
name: George, Joe
name: Wallin, John
name: Shamir, Lior
Publisher: name: arXiv
Year: 2014
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: The increasing importance of digital sky surveys collecting many millions of galaxy images has reinforced the need for robust methods that can perform morphological analysis of large galaxy image databases. Citizen science initiatives such as Galaxy Zoo showed that large datasets of galaxy images can be analyzed effectively by non-scientist volunteers, but since databases generated by robotic telescopes grow much faster than the processing power of any group of citizen scientists, it is clear that computer analysis is required. Here we propose to use citizen science data for training machine learning systems, and show experimental results demonstrating that machine learning systems can be trained with citizen science data. Our findings show that the performance of machine learning depends on the quality of the data, which can be improved by using samples that have a high degree of agreement between the citizen scientists. The source code of the method is publicly available.
description: PASP, accepted
Phase Space dynamics of triaxial collapse: Joint density-velocity evolution
Creators: name: Nadkarni-Ghosh, Sharvari
name: Singhal, Akshat
Publisher: name: arXiv
Year: 2014
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We investigate the dynamics of triaxial collapse in terms of eigenvalues of the deformation tensor, the velocity derivative tensor and the gravity Hessian. Using the Bond-Myers model of ellipsoidal collapse, we derive a new set of equations for the nine eigenvalues and examine their dynamics in phase space. The main advantage of this form is that it eliminates the complicated elliptic integrals that appear in the axes evolution equations and is more natural way to understand the interplay between the perturbations. This paper focuses on the density-velocity dynamics. The Zeldovich approximation implies that the three tensors are proportional; the proportionality constant is set by demanding `no decaying modes'. We extend this condition into the non-linear regime and find that the eigenvalues of the gravity Hessian and the velocity derivative tensor are related as ${\tilde q}_d + {\tilde q}_v=1$, where the triaxiality parameter ${\tilde q} = (λ_{\mathrm{max}} - λ_{\mathrm{inter}})/(λ_{\mathrm{max}} - λ_{\mathrm{min}})$. This is a {\it new universal relation} holding true over all redshifts and a range of mass scales to within a few percent accuracy. The mean density-velocity divergence relation at late times is close to linear, indicating that the dynamics is dictated by collapse along the largest eigendirection. This relation has a scatter, which we show, is intimately connected to the velocity shear. Finally, as an application, we compute the PDFs of the two variables and compare with other forms in the literature.
description: 23 pages (16 text+appendix); 11 figures, revised version accepted for publication in MNRAS
Cosmological applications of $F(T,T_G)$ gravity
Creators: name: Kofinas, Georgios
name: Saridakis, Emmanuel N.
Publisher: name: arXiv
Year: 2014
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We investigate the cosmological applications of $F(T,T_G)$ gravity, which is a novel modified gravitational theory based on the torsion invariant $T$ and the teleparallel equivalent of the Gauss-Bonnet term $T_{G}$. $F(T,T_{G})$ gravity differs from both $F(T)$ theories as well as from $F(R,G)$ class of curvature modified gravity, and thus its corresponding cosmology proves to be very interesting. In particular, it provides a unified description of the cosmological history from early-times inflation to late-times self-acceleration, without the inclusion of a cosmological constant. Moreover, the dark energy equation-of-state parameter can be quintessence or phantom-like, or experience the phantom-divide crossing, depending on the parameters of the model.
description: 10 pages, 4 figures, version published in Phys. Rev. D. arXiv admin note: substantial text overlap with arXiv:1404.2249
Mutagenesis and Background Neutron Radiation
Creators: name: Gonzalez, Augusto
Publisher: name: arXiv
Year: 2014
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: We suggest a possible correlation between the ionization events caused by the background neutron radiation and the experimental data on mutations with damage in the DNA repair mechanism, coming from the Long Term Evolution Experiment in E. Coli populations.
description: submitted to Revista Cubana de Fisica
Ein paar Gedanken zum Schluss
Creators: name: Ammicht Quinn, Regina
name: Junker-Kenny, Maureen
name: Tamez, Elsa
Publisher: name: Concilium
Year: 1970

description: Concilium, Bd. 39 Nr. 2 (2003): Concilium: Internationale Zeitschrift für Theologie, Band 39, Heft 2
Structures of RNA polymerase II complexes with Bye1, a chromatin-binding PHF3/DIDO homologue
Creators: name: Cramer, P.
name: Wozniak, G. G.
name: Strahl, B. D.
name: Kinkelin, K.
name: Rothbart, S. B.
name: Lidschreiber, M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Transcription of protein-coding genes requires transient binding of many different factors to RNA polymerase II. Thus far, crystal structures of only two such factors in complex with RNA polymerase II are known. Here we report crystal structures of a third polymerase-binding protein, bypass of Ess1 (Bye1), in complex with RNA polymerase II in different functional states. We also show that Bye1 binds histone tails with posttranslational modifications that mark active chromatin and discuss models for Bye1 function in a chromatin context.
title: Impacts of climate change on non-native species
Creators: name: Cook, Elizabeth J.
name: Jenkins, Stuart
name: Maggs, Christine
name: Minchin, Dan
name: Mineur, Frédéric
name: Nall, Chris
name: Sewell, Jack
Publisher: name: Marine Climate Change Impacts Partnership (MCCIP), Lowestoft, UK
Year: 2013

description: MCCIP Science Review 2013, 155-166
Surface exposure to sunlight stimulates CO 2 release from permafrost soil carbon in the Arctic
Creators: name: Kling, George W.
name: Dobkowski, Jason A.
name: Crump, Byron C.
name: Cory, Rose M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Recent climate change has increased arctic soil temperatures and thawed large areas of permafrost, allowing for microbial respiration of previously frozen C. Furthermore, soil destabilization from melting ice has caused an increase in thermokarst failures that expose buried C and release dissolved organic C (DOC) to surface waters. Once exposed, the fate of this C is unknown but will depend on its reactivity to sunlight and microbial attack, and the light available at the surface. In this study we manipulated water released from areas of thermokarst activity to show that newly exposed DOC is >40% more susceptible to microbial conversion to CO2 when exposed to UV light than when kept dark. When integrated over the water column of receiving rivers, this susceptibility translates to the light-stimulated bacterial activity being on average from 11% to 40% of the total areal activity in turbid versus DOC-colored rivers, respectively. The range of DOC lability to microbes seems to depend on prior light exposure, implying that sunlight may act as an amplification factor in the conversion of frozen C stores to C gases in the atmosphere.
Synthesis and dissolution of hemicatenanes by type IA DNA topoisomerases
Creators: name: Hsieh, T.-S.
name: Siaw, G. E.-L.
name: Griffith, J. D.
name: Lee, S.-H.
name: Willcox, S.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: A hemicatenane conjoins two DNA duplexes through a single-strand interlock. It has been proposed that hemicatenanes are important intermediates for replication, repair, and recombination. However, the biochemical analysis of hemicatenanes is hampered by the relative inaccessibility of such structures. We report here that a DNA topoisomerase III (Top3) from a hyperthermophilic archaeum can carry out synthesis and dissolution of hemicatenanes. We also show that a complex of human Top3α, Bloom helicase (Blm), and RecQ-mediated genome instability protein 1 and 2 has a biochemical function of reversing this hemicatenation. Our results demonstrate that type IA topoisomerases can regulate the formation of hemicatenane structures.
Superconducting TiN Films Sputtered over a Large Range of Substrate DC Bias
Creators: name: Jaim, H. M. Iftekhar
name: Aguilar, J. A.
name: Sarabi, B.
name: Rosen, Y. J.
name: Ramanayaka, A. N.
name: Lock, E. H.
name: Richardson, C. J. K.
name: Osborn, K. D.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We have investigated properties of superconducting titanium nitride (TiN) films that were sputtered over a large range of RF-induced DC bias voltage applied to the substrate. Films grown with the largest bias voltages contained cubic TiN phases with a large fraction of the (200) crystalline growth orientation. These films also contained the smallest concentrations of oxygen impurities, resulting in stoichiometric TiN. Over the range of bias, variations of the stress from slightly tensile to highly compressive were measured and correlated to crystallinity of the (200) growth. The films exhibited highly uniform thickness and resistivity, and show the potential for yielding reproducible low-temperature devices. Finally, coplanar resonators fabricated with the films exhibited high kinetic inductance and quality factor, where the latter was obtained in part from temperature-dependent frequency shifts.
Energy spectrum of a harmonically trapped two-atom system with spin-orbit coupling
Creators: name: Guan, Q.
name: Yin, X. Y.
name: Gharashi, S. E.
name: Blume, D.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Ultracold atomic gases provide a novel platform with which to study spin-orbit coupling, a mechanism that plays a central role in the nuclear shell model, atomic fine structure and two-dimensional electron gases. This paper introduces a theoretical framework that allows for the efficient determination of the eigenenergies and eigenstates of a harmonically trapped two-atom system with short-range interaction subject to an equal mixture of Rashba and Dresselhaus spin-orbit coupling created through Raman coupling of atomic hyperfine states. Energy spectra for experimentally relevant parameter combinations are presented and future extensions of the approach are discussed.
description: 2 figures (several subfigures)
TRA-1 ChIP-seq reveals regulators of sexual differentiation and multilevel feedback in nematode sex determination
Creators: name: Lieb, J. D.
name: Zarkower, D.
name: Ikegami, K.
name: Arur, S.
name: Berkseth, M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Sex-determining genes have been identified in many animals, but how they impose sex specificity on development is poorly understood. We ask how the nematode sex-determining transcription factor Transformer 1 (TRA-1) regulates sex by identifying where in the genome TRA-1 binds and which nearby genes may be affected by this binding. We find that TRA-1 promotes female development primarily by preventing the expression of genes involved in male development. Among the genes repressed by TRA-1 are a number that control the timing of developmental events and also several that function upstream of TRA-1 in the global sex-determination pathway. The suite of TRA-1 targets presented here provides a resource to continue uncovering the basis of sex-specific development.
Vegetation controls on the maximum size of coastal dunes
Creators: name: Moore, L. J.
name: Duran, O.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Coastal dunes, in particular foredunes, support a resilient ecosystem and reduce coastal vulnerability to storms. In contrast to dry desert dunes, coastal dunes arise from interactions between biological and physical processes. Ecologists have traditionally addressed coastal ecosystems by assuming that they adapt to preexisting dune topography, whereas geomorphologists have studied the properties of foredunes primarily in connection to physical, not biological, factors. Here, we study foredune development using an ecomorphodynamic model that resolves the coevolution of topography and vegetation in response to both physical and ecological factors. We find that foredune growth is eventually limited by a negative feedback between wind flow and topography. As a consequence, steady-state foredunes are scale invariant, which allows us to derive scaling relations for maximum foredune height and formation time. These relations suggest that plant zonation (in particular for strand “dune-building” species) is the primary factor controlling the maximum size of foredunes and therefore the amount of sand stored in a coastal dune system. We also find that aeolian sand supply to the dunes determines the timescale of foredune formation. These results offer a potential explanation for the empirical relation between beach type and foredune size, in which large (small) foredunes are found on dissipative (reflective) beaches. Higher waves associated with dissipative beaches increase the disturbance of strand species, which shifts foredune formation landward and thus leads to larger foredunes. In this scenario, plants play a much more active role in modifying their habitat and altering coastal vulnerability than previously thought.
Arthritogenic alphaviral infection perturbs osteoblast function and triggers pathologic bone loss
Creators: name: Mahalingam, S.
name: Taylor, A.
name: Rulli, N. E.
name: Lidbury, B. A.
name: Li, R. W.
name: Herrero, L. J.
name: Foo, S.-S.
name: Herring, B. L.
name: Sims, N. A.
name: Chen, W.
name: Smith, P. N.
name: Walsh, N. C.
name: Sheng, K.-C.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2014

description: Persistent polyarthritis, which occurs in 30–40% of alphavirus-infected patients, has been proposed to be caused by proinflammatory mediators such as IL-6. In the present study we investigated the susceptibility and response of primary human osteoblasts to Ross River virus (RRV) infection and determined whether infection could result in bone pathology. RRV infection of osteoblasts resulted in increased receptor activator of nuclear factor-kappaB ligand (RANKL) but decreased osteoprotegerin (OPG). We are the first to report that alphavirus infection results in bone loss in an established RRV murine model and that this bone loss is prevented by IL-6 inhibition. These findings reveal that RRV can disrupt bone homeostasis and that osteoblasts play an important role in alphavirus-induced arthritis by regulating IL-6 and contribute to bone loss by disrupting the RANKL/OPG balance.
Transport modelling at SBB
Creators: name: Danalet, Antonin
Publisher: name: Zenodo
Year: 2023
Subjects: Switzerland
MATSim
tourists
SIMBA
agent-based model
SIMBA MOBi
SBB
Swiss Railways
mode choice
main transport mode
tourist accommodation

description: Lecture given at EPFL as part of the course "Introduction to transportation systems" (Bachelor semester 6, Civil engineering). To see the video on slide 32: https://api.eu.kaltura.com/html5/html5lib/v2.98/mwEmbedFrame.php/p/324/uiconf_id/23453841/entry_id/0_mppdaxl3?wid=_324&iframeembed=true&playerId=kaltura_player&entry_id=&wid=0_h4mrwvlw
Consensus reaching in swarms ruled by a hybrid metric-topological distance
Creators: name: Shang, Yilun
name: Bouffanais, Roland
Publisher: name: arXiv
Year: 2014
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: Recent empirical observations of three-dimensional bird flocks and human crowds have challenged the long-prevailing assumption that a metric interaction distance rules swarming behaviors. In some cases, individual agents are found to be engaged in local information exchanges with a fixed number of neighbors, i.e. a topological interaction. However, complex system dynamics based on pure metric or pure topological distances both face physical inconsistencies in low and high density situations. Here, we propose a hybrid metric-topological interaction distance overcoming these issues and enabling a real-life implementation in artificial robotic swarms. We use network- and graph-theoretic approaches combined with a dynamical model of locally interacting self-propelled particles to study the consensus reaching pro- cess for a swarm ruled by this hybrid interaction distance. Specifically, we establish exactly the probability of reaching consensus in the absence of noise. In addition, simulations of swarms of self-propelled particles are carried out to assess the influence of the hybrid distance and noise.
Caenorhabditis elegans RSD-2 and RSD-6 promote germ cell immortality by maintaining small interfering RNA populations
Creators: name: Alvares, S. M.
name: LaRocque, J. R.
name: Hall, J.
name: Yang, L.
name: Sarkies, P.
name: Ahmed, S.
name: Simon, M.
name: Goldstein, L. D.
name: Doebley, A.-L.
name: Miska, E. A.
name: Sakaguchi, A.
name: Ikegami, K.
name: Hedges, A.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2014

description: Here, we establish a role for small RNAs in promoting transgenerational fertility via an endogenous temperature-sensitive silencing process that is promoted by the RNAi spreading defective (RSD)-2 and RSD-6 proteins, which have been implicated in RNA interference in response to exogenous double-stranded RNA triggers. This process could be broadly relevant to transgenerational maintenance of heterochromatin and is plausibly relevant to regulation of aging of somatic cells as they proliferate.