cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
AMS :: ATX February 2019 Blog Archive
Creators: name: Department Of American Studies
Publisher: name: American Studies
Year: 2019
Subjects: American Studies
Twitter

description: Contents: This Thursday (2/7): Performance and Conversation with Dallas Artist Francine Thirteen -- Catch Genevieve Gaignard’s “In Passing” at the Christian-Green Gallery -- Go See “Fugitive Findings” at the Harry Ransom Center -- This Friday, February 15: “Losing Ground” Film Screening and Conversation at the Bullock Museum -- Wednesday, February 20th: American Studies Film Club Screening of “Taxi Driver” -- Fugitive Futures: Graduate Students of Color Un-Settling the University (This Friday and Saturday!)
description: @AmStudies is a Twitter feed dedicated to representing the many activities and interests of the department of American Studies at The University of Texas at Austin. Together with the department’s blog, this feed exists to serve the AMS and Austin communities by acting as a hub for up-to-date information on events and opportunities at UT and beyond.
The response of rainbow trout Salmo gairdneri to lures with special references to color preference
Creators: name: Dooley, Robert H. A.
Publisher: name: University of British Columbia
Year: 2010

description: The response of rainbow trout (Salmo gairdneri) to lures was investigated in trolling experiments at Loon Lake, British Columbia. The "action" of a lure was found to be an important parameter in determining its efficiency: of four actions tested, the flatfish caught the greatest number of fish. Although the color of lure was not significant, red lures were more efficient than yellow, green, and blue, and more efficient than various color patterns of red and white. The presence of a dodger with lures did not affect their efficiency, but larger fish were caught. No size selection occurred with either colors or actions of lures. In laboratory feeding experiments using dyed trout eggs as food, red was selected first or second more often than yellow, green, or blue. The color of background against which the fish were fed, and individual differences among fish caused significant changes in the preference shown for various colors of food. Combining two colors also affected the selection intensity, depending upon the contrast between the two colors. Preferences for different colors of food were not influenced by the hunger level of the fish, measured in terms of the quantity of food in the fish's gut. In the course of the experiments it was incidentally observed: (1) that rainbow trout possess a striking ability to match the hue of their skin (mainly in the dorsal region) to that of the background in which they are kept; (Z) the color of background affects the activity level of rainbow trout: yellow produces the highest level of activity and green the lowest.
Quantum Wigner entropy
Creators: name: Van Herstraeten, Zacharie
name: Cerf, Nicolas J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We define the Wigner entropy of a quantum state as the differential Shannon entropy of the Wigner function of the state. This quantity is properly defined only for states that possess a positive Wigner function, which we name Wigner-positive states, but we argue that it is a proper measure of quantum uncertainty in phase space. It is invariant under symplectic transformations (displacements, rotations, and squeezing) and we conjecture that it is lower bounded by $\lnπ+1$ within the convex set of Wigner-positive states. It reaches this lower bound for Gaussian pure states, which are natural minimum-uncertainty states. This conjecture bears a resemblance with the Wehrl-Lieb conjecture, and we prove it over the subset of passive states of the harmonic oscillator which are of particular relevance in quantum thermodynamics. Along the way, we present a simple technique to build a broad class of Wigner-positive states exploiting an optical beam splitter and reveal an unexpectedly simple convex decomposition of extremal passive states. The Wigner entropy is anticipated to be a significant physical quantity, for example, in quantum optics where it allows us to establish a Wigner entropy-power inequality. It also opens a way towards stronger entropic uncertainty relations. Finally, we define the Wigner-Rényi entropy of Wigner-positive states and conjecture an extended lower bound that is reached for Gaussian pure states.
description: Published version with minor corrections, added details, and new Appendices on the Wigner-Renyi entropy and on the convex decomposition of extremal passive states
AMS :: ATX April 2019 Blog Archive
Creators: name: Department Of American Studies
Publisher: name: American Studies
Year: 2019
Subjects: American Studies
Twitter

description: Content: Andrew Busch to Give Talk at Austin History Center, 4/25, 6:30 PM
description: @AmStudies is a Twitter feed dedicated to representing the many activities and interests of the department of American Studies at The University of Texas at Austin. Together with the department’s blog, this feed exists to serve the AMS and Austin communities by acting as a hub for up-to-date information on events and opportunities at UT and beyond.
Dynamical models and the phase ordering kinetics of the s=1 spinor condensate
Creators: name: Mukerjee, Subroto
name: Xu, Cenke
name: Moore, Joel E.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The $s=1$ spinor Bose condensate at zero temperature supports ferromagnetic and polar phases that combine magnetic and superfluid ordering. We investigate the formation of magnetic domains at finite temperature and magnetic field in two dimensions in an optical trap. We study the general ground state phase diagram of a spin-1 system and focus on a phase that has a magnetic Ising order parameter and numerically determine the nature of the finite temperature superfluid and magnetic phase transitions. We then study three different dynamical models: model A, which has no conserved quantities, model F, which has a conserved second sound mode and the Gross-Pitaevskii (GP) equation which has a conserved density and magnetization. We find the dynamic critical exponent to be the same for models A and F ($z=2$) but different for GP ($z \approx 3$). Externally imposed magnetization conservation in models A and F yields the value $z \approx 3$, which demonstrates that the only conserved density relevant to domain formation is the magnetization density.
description: 14 pages with 9 figures
AMS :: ATX May 2019 Blog Archive
Creators: name: Department Of American Studies
Publisher: name: American Studies
Year: 2019
Subjects: American Studies
Twitter

description: Contents: Dr. Nicole Guidotti-Hernández to Co-Edit “Latinx: The Future is Now” Series with UT Press -- UT AMS PhD Candidate Josh Kopin Co-Edits Roundtable on Sound in Comics -- What We’re Looking Forward To This Summer: UT AMS’s Summer Plans -- An Interview with Michael Ayala, Honored Graduate of UT AMS’ Undergraduate Program -- Meet AMS Undergrad Natalie Fisher, Honorable Mention on Dean’s Distinguished Graduates List
description: @AmStudies is a Twitter feed dedicated to representing the many activities and interests of the department of American Studies at The University of Texas at Austin. Together with the department’s blog, this feed exists to serve the AMS and Austin communities by acting as a hub for up-to-date information on events and opportunities at UT and beyond.
Chiral Plaquette Polaron Theory of Cuprate Superconductivity
Creators: name: Tahir-Kheli, Jamil
name: Goddard, William A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Ab-initio density functional calculations on explicitly doped La(2-x)Sr(x)CuO4 find doping creates localized holes in out-of-plane orbitals. A model for superconductivity is developed based on the assumption that doping leads to the formation of holes on a four-site Cu plaquette composed of the out-of-plane A1 orbitals apical O pz, planar Cu dz2, and planar O psigma. This is in contrast to the assumption of hole doping into planar Cu dx2-y2 and O psigma orbitals as in the t-J model. Interaction of holes with the d9 spin background leads to chiral polarons with either a clockwise or anti-clockwise charge current. When the polaron plaquettes percolate through the crystal at x~0.05 for LaSrCuO, a Cu dx2-y2 and planar O psigma band is formed. Spin exchange Coulomb repulsion with chiral polarons leads to D-wave superconductivity. The equivalent of the Debye energy in phonon superconductivity is the maximum energy separation between a chiral polaron and its time-reversed partner. An additive skew-scattering contribution to the Hall effect is induced by chiral polarons and leads to a temperature dependent Hall effect that fits the measured values for LaSrCuO. The integrated imaginary susceptibility satisfies omega/T scaling due to chirality and spin-flip scattering of polarons along with a uniform distribution of polaron energy splittings. The derived functional form is compatible with experiments. The static spin structure factor is computed and is incommensurate with a separation distance from (pi,pi) given by ~(2pi)x. Coulomb scattering of the x2-y2 band with polarons leads to linear resistivity. Coupling of the x2-y2 band to the undoped Cu d9 spins leads to the ARPES pseudogap and its doping and temperature dependence.
description: 32 pages, 17 figures
Fracton physics of spatially extended excitations. II. Polynomial ground state degeneracy of exactly solvable models
Creators: name: Li, Meng-Yuan
name: Ye, Peng
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Generally, ``fracton'' topological orders are referred to as gapped phases that support \textit{point-like topological excitations} whose mobility is, to some extent, restricted. In our previous work [Phys. Rev. B 101, 245134 (2020)], a large class of exactly solvable models on hypercubic lattices are constructed. In these models, \textit{spatially extended excitations} possess generalized fracton-like properties: not only mobility but also deformability is restricted. As a series work, in this paper, we proceed further to compute ground state degeneracy (GSD) in both isotropic and anisotropic lattices. We decompose and reconstruct ground states through a consistent collection of subsystem ground state sectors, in which mathematical game ``coloring method'' is applied. Finally, we are able to systematically obtain GSD formulas (expressed as $\log_2 GSD$) which exhibit diverse kinds of polynomial dependence on system sizes. For example, the GSD of the model labeled as $[0,1,2,4]$ in four dimensional isotropic hypercubic lattice shows $ 12L^2-12L+4$ dependence on the linear size $L$ of the lattice. Inspired by existing results [Phys. Rev. X 8, 031051 (2018)], we expect that the polynomial formulas encode geometrical and topological fingerprints of higher-dimensional manifolds beyond toric manifolds used in this work. This is left to future investigation.
description: See also: arXiv:1909.02814; Accepted by Phys. Rev. B
1/2-BPS states in M theory and defects in the dual CFTs
Creators: name: Lunin, Oleg
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study supersymmetric branes in AdS_7 x S^4 and AdS_4 x S^7. We show that in the former case the membranes should be viewed as M5 branes with fluxes and we identify two types of such fivebranes (they are analogous to giant gravitons and to dual giants). In AdS_4 x S^7 we find both M5 branes with fluxes and freestanding stacks of membranes. We also go beyond probe approximation and construct regular supergravity solutions describing geometries produced by the branes. The metrics are completely specified by one function which satisfies either Laplace or Toda equation and we give a complete classification of boundary conditions leading to smooth geometries. The brane configurations discussed in this paper are dual to various defects in three- and six-dimensional conformal field theories.
description: 82 pages, 12 figures, added refs
N-jettiness in electroweak high-energy processes
Creators: name: Chay, Junegone
name: Ha, Taewook
name: Kwon, Taehyun
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study $N$-jettiness in electroweak processes at extreme high energies. The description of the scattering process such as $e^- e^+ \rightarrow μ^- μ^+ +X$ is similar to QCD. At present, electroweak processes are prevailed by the processes induced by the strong interaction, but they will be relevant at future $e^- e^+$ colliders at high energy. The main difference between QCD and electroweak processes is that the initial- and final-state particles should appear in the form of hadrons, that is, color singlets in QCD, while there can be weak nonsinglets as well in electroweak interactions. We analyze the factorization theorems for the $N$-jettiness in $e^- e^+ \rightarrow μ^- μ^+ +X$, and compute the factorized parts to next-to-leading logarithmic accuracy. To simplify the comparison with QCD, we only consider the $SU(2)_W$ gauge interaction, and the extension to the Standard Model is straightforward. Put it in a different way, it corresponds to an imaginary world in which colored particles can be observed in QCD, and the richer structure of effective theories is probed. Various nonzero nonsinglet matrix elements are interwoven to produce the factorized results, in contrast to QCD in which there are only contributions from the singlets. Another distinct feature is that the rapidity divergence is prevalent in the contributions from weak nonsinglets due to the different group theory factors between the real and virtual corrections. We verify that the rapidity divergence cancels in all the contributions with a different number of nonsinglet channels. We also consider the renormalization group evolution of each factorized part to resum large logarithms, which are distinct from QCD.
description: Journal version for JHEP. Major revision: 52 pages, 7 figures
Theory of Star Formation
Creators: name: McKee, Christopher F.
name: Ostriker, Eve C.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We review current understanding of star formation, outlining an overall theoretical framework and the observations that motivate it. A conception of star formation has emerged in which turbulence plays a dual role, both creating overdensities to initiate gravitational contraction or collapse, and countering the effects of gravity in these overdense regions. The key dynamical processes involved in star formation -- turbulence, magnetic fields, and self-gravity -- are highly nonlinear and multidimensional. Physical arguments are used to identify and explain the features and scalings involved in star formation, and results from numerical simulations are used to quantify these effects. We divide star formation into large-scale and small-scale regimes and review each in turn. Large scales range from galaxies to giant molecular clouds (GMCs) and their substructures. Important problems include how GMCs form and evolve, what determines the star formation rate (SFR), and what determines the initial mass function (IMF). Small scales range from dense cores to the protostellar systems they beget. We discuss formation of both low- and high-mass stars, including ongoing accretion. The development of winds and outflows is increasingly well understood, as are the mechanisms governing angular momentum transport in disks. Although outstanding questions remain, the framework is now in place to build a comprehensive theory of star formation that will be tested by the next generation of telescopes.
description: 120 pages, to appear in ARAA. No changes from v1 text; permission statement added
AMS :: ATX March 2019 Blog Archive
Creators: name: Department Of American Studies
Publisher: name: American Studies
Year: 2019
Subjects: American Studies
Twitter

description: Contents: Tuesday, March 5th: “Before 13th: The Origin of Convict Leasing” with Dr. Michael Ralph -- New Episode of Dr. Lauren Gutterman’s “Sexing History” Podcast: “Sherri” -- This Friday (3/8): UT AMS Faculty to Present at Humanities Research Symposium -- UT AMS Introduces Students to the Fun of American Studies at Explore UT -- Tomorrow and Friday (3/14 & 3/15): Black Studies @ 50 Conference at UT -- UT AMS PhD Student Ja’nell N. Ajani Hosts SXSW EDU Panel on “Prisons as a Learning Space” -- UT AMS Hosts Graduate Conference: Tell-Tale Traces: Living Memory in the United States
description: @AmStudies is a Twitter feed dedicated to representing the many activities and interests of the department of American Studies at The University of Texas at Austin. Together with the department’s blog, this feed exists to serve the AMS and Austin communities by acting as a hub for up-to-date information on events and opportunities at UT and beyond.
Coherence of an Entangled Exciton-Photon State
Creators: name: Hudson, A. J.
name: Stevenson, R. M.
name: Bennett, A. J.
name: Young, R. J.
name: Nicoll, C. A.
name: Atkinson, P.
name: Cooper, K.
name: Ritchie, D. A.
name: Shields, A. J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study the effect of the exciton fine-structure splitting on the polarisation-entanglement of photon pairs produced by the biexciton cascade in a single quantum dot. The entanglement is found to persist despite separations between the intermediate energy levels of up to 4 micro-eV. Measurements demonstrate that entanglement of the photon pair is robust to the dephasing of the intermediate exciton state responsible for the first order coherence time of either single photon. We present a theoretical framework taking into account the effects of spin-scattering, background light and dephasing. We distinguish between the first-order coherence time, and a parameter which we measure for the first time and define as the cross-coherence time.
AMS :: ATX September 2018 Blog Archive
Creators: name: Department Of American Studies
Publisher: name: American Studies
Year: 2018
Subjects: American Studies
Twitter

description: Contents: Book Talk: “Remaking Black Power: How Black Women Transformed an Era” by Ashley D. Farmer (9/13) -- What I Did On My Summer Vacation: Nick Bloom on Touring with Bold Forbes -- Mitch Landrieu, Former Mayor of New Orleans, in Conversation with Angela Evans, Dean of LBJ School of Public Affairs (9/18) -- What I Did On My Summer Vacation: Leah Butterfield on Interviewing Women Solo Travelers in Spain -- A Conversation with Ben Lisle (PhD 2010), Author of 2017 Monograph “Modern Coliseum: Stadiums and American Culture” -- This Friday (9/21): Award-Winning Hip Hop Journalist Joan Morgan in Conversation with Dr. Lisa B. Thompson -- Cary Cordova, Steve Hoelscher to participate in “Facing Racism: Art & Action” Symposium at the Blanton (9/27) -- What I Did On My Summer Vacation: Caroline Johnson on Interning at the Smithsonian Air and Space Museum -- Dr. Lauren Gutterman Debuts Second Season of “Sexing History” Podcast -- A Conversation with Molly Mandell (B.A. 2016), Author of “Made in Cuba” (2018)
description: @AmStudies is a Twitter feed dedicated to representing the many activities and interests of the department of American Studies at The University of Texas at Austin. Together with the department’s blog, this feed exists to serve the AMS and Austin communities by acting as a hub for up-to-date information on events and opportunities at UT and beyond.
The Normalization of Japan-China relations : external and internal influences on Japan’s foreign policy-making progress
Creators: name: Hook, Glen Dawson
Publisher: name: University of British Columbia
Year: 2010

description: There have been few studies that have explicitly attempted to delineate the influence of external and internal factors on Japan's foreign policy-making process. The purpose of this thesis is to examine such factors in respect to one particular foreign policy issue: the normalization of relations between Japan and China. So as not to be considered as purely idiographic research, the findings are contrasted and compared with previous research that has similarly been concerned with a 1) foreign policy issue, 2) controversial in characteristic, and 3) short-term on the temporal dimension. After the limitations of the tripartite elite model of Japanese policy-making are outlined, an examination is then made of the influence of the United States and China in compelling Japan's decision to normalize relations with China. Internally, the role of the Liberal Democratic Party, bureaucracy, business, opposition parties, press and public opinion are assessed in respect to this and previous policy studies. Our findings here are consistent with the conclusion that the tripartite elite (the Liberal Democratic Party, bureaucracy, and business) does not necessarily hold predominant power in the policymaking process. Instead, we find that two senior leaders of the ruling Liberal Democratic Party — Prime Minister Tanaka and Foreign Minister Ohira — form a policy-making group which dominates this particular policy process. These politicians are supported in this role by senior members of the bureaucracy, a pro-Peking Liberal Democratic Party Dietman, and influential members of the opposition parties. In this study, the role of business, the press and public opinion are found to be indirect and peripheral compared to the role played by the above mentioned policy-making actors.
Lower Spectral Branches of a Spin-Boson Model
Creators: name: Angelescu, Nicolae
name: Minlos, Robert
name: Ruiz, Jean
name: Zagrebnov, Valentin
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We study the structure of the spectrum of a two-level quantum system weakly coupled to a boson field (spin-boson model). Our analysis allows to avoid the cutoff in the number of bosons, if their spectrum is bounded below by a positive constant. We show that, for small coupling constant, the lower part of the spectrum of the spin-boson Hamiltonian contains (one or two) isolated eigenvalues and (respectively, one or two) manifolds of atom $+ 1$-boson states indexed by the boson momentum $q$. The dispersion laws and generalized eigenfunctions of the latter are calculated.
Advanced 3D Monte Carlo algorithms for biophotonic and medical applications
Creators: name: McMillan, Lewis
Publisher: name: University of St Andrews
Year: 2020

description: The Monte Carlo radiation transfer (MCRT) method can simulate the transport of light through turbid media. MCRT allows the modelling of multiple anisotropic scattering events, as well as a range of microphysics such as polarisation and fluorescence. This thesis concerns the development of several MCRT algorithms to solve various biophotonic and medically-related problems including modelling of tissue ablation and autofluorescent signals. An extension of the MCRT method through a theoretical quasi-wave/particle model is also demonstrated, allowing beam shapes with arbitrary phase profiles to be propagated. Tissue ablation can be used to treat acne scarring, Rhinophyma, and it can also be used to help enhance topical drug delivery. Currently the depth of ablation is not easily elucidated from a given laser or laser power setting. Therefore, a numerical tissue ablation model is developed using a combination of MCRT, a heat diffusion model, and a numerical tissue damage model to assess ablation crater depth and thermal damage to the surrounding tissue. Autofluorescence is the natural fluorescence of biological structures in tissue. Autofluorescence can be used as a biomarker of several diseases including: cardiovascular diseases, Alzheimers, and diabetes. However, the origin of the autofluorescence signal is not completely clear. The effect of tissue optics on the signal, which fluorophores contribute to the signal and by how much, and how different locations on the body can affect the signal are not well understood. This thesis presents a study of the effect of tissue optics on the autofluorescent signal. As part of this study, AmoebaMCRT was created to determine the relative concentrations of fluorophores for a given autofluorescent signal. Finally, we developed an extension to the MCRT method which allows the simulation of quasi-wave/particles. This method relies on the Huygens-Fresnel principle and the tracking of the phase of each individual photon packet. The extension, φMC, allows the modelling of complex beams that require the wave properties of light such as arbitrary order Bessel beams and Gaussian beams. We then use φMC to predict which beam, Bessel or Gaussian, performs “better" in a highly turbid medium.
Credit risk - A structural model with jumps and correlations
Creators: name: Schäfer, Rudi
name: Sjölin, Markus
name: Sundin, Andreas
name: Wolanski, Michal
name: Guhr, Thomas
Publisher: name: arXiv
Year: 2007
Subjects: subject: Risk Management (q-fin.RM)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Physics and Society (physics.soc-ph)
subject: Statistical Finance (q-fin.ST)
subject: FOS: Economics and business
subject: FOS: Physical sciences

description: We set up a structural model to study credit risk for a portfolio containing several or many credit contracts. The model is based on a jump--diffusion process for the risk factors, i.e. for the company assets. We also include correlations between the companies. We discuss that models of this type have much in common with other problems in statistical physics and in the theory of complex systems. We study a simplified version of our model analytically. Furthermore, we perform extensive numerical simulations for the full model. The observables are the loss distribution of the credit portfolio, its moments and other quantities derived thereof. We compile detailed information about the parameter dependence of these observables. In the course of setting up and analyzing our model, we also give a review of credit risk modeling for a physics audience.
description: 24 pages
Multi-Objective CFD-Driven Development of Coupled Turbulence Closure Models
Creators: name: Waschkowski, Fabian
name: Zhao, Yaomin
name: Sandberg, Richard
name: Klewicki, Joseph
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: This paper introduces two novel concepts in data-driven turbulence modeling that enable the simultaneous development of multiple closure models and the training towards multiple objectives. The concepts extend the evolutionary framework by Weatheritt and Sandberg (2016), which derives interpretable and implementation-ready expressions from high-fidelity simulation data. By assigning a shared fitness value to the evolved closure models and utilizing the CFD-driven training approach by Zhao et al. (2020), the multi-expression training concept introduced here is able to account for the coupling between the trained models, i.e. Reynolds stress anisotropy, turbulent heat flux and turbulence production correction models. As a second concept, a multi-objective optimization algorithm is applied to the framework. The extension yields a diverse set of candidate models and allows a trade-off between the training objectives after analyzing the training results. In this study, the novel concepts are applied to a benchmark periodic hills case and a vertical natural convection flow. The predictions of mean flow quantities are improved compared to decoupled training strategies with distinct and robust improvements for strongly coupled momentum and thermal fields. The coupled training of closure models and the balancing of multiple training objectives are considered important capabilities on the path towards generalized data-driven turbulence models.
description: Accepted by Journal of Computational Physics
Lysine acetylation regulates the interaction between proteins and membranes
Creators: name: Okada, Alan K.
name: Teranishi, Kazuki
name: Ambroso, Mark R.
name: Isas, Jose Mario
name: Vazquez-Sarandeses, Elena
name: Lee, Joo-Yeun
name: Melo, Arthur Alves
name: Pandey, Priyatama
name: Merken, Daniel
name: Berndt, Leona
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Acetylation
subject: Computational biophysics
subject: Membrane biophysics
subject: Membrane curvature
subject: Membrane lipids
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften

description: Lysine acetylation regulates the function of soluble proteins in vivo, yet it remains largely unexplored whether lysine acetylation regulates membrane protein function. Here, we use bioinformatics, biophysical analysis of recombinant proteins, live-cell fluorescent imaging and genetic manipulation of Drosophila to explore lysine acetylation in peripheral membrane proteins. Analysis of 50 peripheral membrane proteins harboring BAR, PX, C2, or EHD membrane-binding domains reveals that lysine acetylation predominates in membrane-interaction regions. Acetylation and acetylation-mimicking mutations in three test proteins, amphiphysin, EHD2, and synaptotagmin1, strongly reduce membrane binding affinity, attenuate membrane remodeling in vitro and alter subcellular localization. This effect is likely due to the loss of positive charge, which weakens interactions with negatively charged membranes. In Drosophila, acetylation-mimicking mutations of amphiphysin cause severe disruption of T-tubule organization and yield a flightless phenotype. Our data provide mechanistic insights into how lysine acetylation regulates membrane protein function, potentially impacting a plethora of membrane-related processes.
On the dynamics of the torus around the kicked black hole
Creators: name: Donmez, Orhan
name: Al-Kandari, Anwar
name: Seedo, Ahlam Abu
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: There is a special interest to understand the dynamical properties of the accretion disk created around the newly formed black hole due to the supermassive black hole binaries which merge inside the gaseous disk. The newly formed black hole would have a kick velocity at up to thousands of km/s that drives a perturbation on a newly accreted torus around the black hole. Some of the observed supermassive black holes at the center of the Active Galactic Nucleus (AGN) move with a certain velocity relative to its broader accretion disk. In this paper, the effects of the kicked black holes onto the infinitesimally thin accreted torus are studied by using the general relativistic hydrodynamical code, focusing on changing the dynamics of the accretion disk during the accretion disk-black hole interaction. We have found the non-axisymmetric global mode m=1 inhomogeneity, which causes a spiral-wave structure, is excited on the torus due to kicked black hole. The higher the perturbation velocity produced by the kicked black hole, the longer time the torus takes to reach the saturation point. The created spiral density waves which rapidly evolve into the spiral shocks are also observed from the numerical simulations. The spiral shock is responsible for accreting matter toward the black hole. Firstly, the spiral-wave structure is developed and the accretion through the spiral arms is stopped around the black hole. At the later time of simulation, the formed spiral shocks partly cause the angular momentum loss across the torus.
description: 25 pages, 13 figures. New references are added. Major changes, revised version accepted for publication in MPLA
Effect of vitamin D supplementation on N‐glycan branching and cellular immunophenotypes in MS
Creators: name: Bäcker‐Koduah, Priscilla
name: Infante‐Duarte, Carmen
name: Ivaldi, Federico
name: Uccelli, Antonio
name: Bellmann‐Strobl, Judith
name: Wernecke, Klaus‐Dieter
name: Sy, Michael
name: Demetriou, Michael
name: Dörr, Jan
name: Paul, Friedemann
name: Brandt, Alexander Ulrich
Publisher: name: Charité - Universitätsmedizin Berlin
Year: 2020
Subjects: subject: B-Lymphocyte Subsets
subject: Cholecalciferol
subject: Immunologic Factors
subject: Polysaccharides
subject: Multiple Sclerosis, Relapsing-Remitting
subject: 600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit::610 Medizin und Gesundheit

description: Objective: To investigate the effect of cholecalciferol (vitamin D3) supplementation on peripheral immune cell frequency and N-glycan branching in patients with relapsing-remitting multiple sclerosis (RRMS). Methods: Exploratory analysis of high-dose (20 400 IU) and low-dose (400 IU) vitamin D3 supplementation taken every other day of an 18-month randomized controlled clinical trial including 38 RRMS patients on stable immunomodulatory therapy (NCT01440062). We investigated cholecalciferol treatment effects on N-glycan branching using L-PHA stain (phaseolus vulgaris leukoagglutinin) at 6 months and frequencies of T-, B-, and NK-cell subpopulations at 12 months with flow cytometry. Results: High-dose supplementation did not change CD3+ T cell subsets, CD19+ B cells subsets, and NK cells frequencies, except for CD8+ T regulatory cells, which were reduced in the low-dose arm compared to the high-dose arm at 12 months. High-dose supplementation decreased N-glycan branching on T and NK cells, measured as L-PHA mean fluorescence intensity (MFI). A reduction of N-glycan branching in B cells was not significant. In contrast, low-dose supplementation did not affect N-glycan branching. Changes in N-glycan branching did not correlate with cell frequencies. Interpretation: Immunomodulatory effect of vitamin D may involve regulation of N-glycan branchingin vivo. Vitamin D3 supplementation did at large not affect the frequencies of peripheral immune cells.
title: Scheitern: ein Leitfaden
Creators: name: Die Junge Akademie
Publisher: name: MyCoRe Community
Year: 2013
Subjects: subject: Nachhaltigkeit
subject: Wirtschaftssoziologie
subject: Bildungsforschung
subject: Risikoforschung
subject: Entscheidungsprozess
subject: Visions and Images of Fascination
subject: Ethikkonflikte
subject: Jonge Academie
subject: 000

description: Wer scheitert, dem misslingt etwas, der erfüllt nicht die Erwartungen, die an ihn gestellt werden oder die er sich selbst setzt, der verfehlt ein Ziel und muss sich von Wünschen und Träumen verabschieden. Für gewöhnlich ist Scheitern negativ besetzt. Aber warum eigentlich? Die Antworten der Mitglieder der Jungen Akademie (JA) in unserem Dossier „Scheitern“ sind erstaunlich positiv: „Scheitern weist uns den Weg zu vielen weiteren, besseren Fragen“, meint Emanuel Towfigh, und Robert Wolf sagt: „Scheitern ist Teil unseres Laboralltags.“ Die Idee zum Dossier „Scheitern“ wurde während der Ideenwerkstatt im Winter 2012 in Weimar entwickelt. Ist selbstbestimmtes Scheitern besseres Scheitern? Kann man nur scheitern, wenn man gescheit ist? Ist man in der Wissenschaft gescheitert, wenn man keine Professur bekommt? Aus der Vielzahl der Fragen konnten wir nur eine Auswahl im Dossier aufgreifen. Mitglieder der AG Nachhaltigkeit haben sich mit Erfolg und Scheitern von Nachhaltigkeit auseinandergesetzt, in den Bereichen Finanzen, Ökologie und Hochschule. Wie unterschiedlich Systeme und Individuen mit (scheinbarem) Scheitern umgehen, beschreiben der Wirtschaftswissenschaftler Moritz Schularick und die Soziologin Magdalena Nowicka in ihren Beiträgen. Scheitern orientiert sich an gesellschaftlichen Normen, weshalb Scheitern in Erzählungen oft umgedeutet wird. Dies ist auch dem Risikoforscher Wolfgang Gaissmaier bewusst: Biografien zeigten, „was alles funktioniert hat“ – und das sei verglichen mit dem, was nicht geklappt habe, recht wenig. In der zweiten Hefthälfte finden Sie wie immer Berichte aus den Arbeits- und Projektgruppen der Jungen Akademie. Ein großer Erfolg war der erste Fotowettbewerb, den die Junge Akademie zusammen mit Partnern aus den Niederlanden, Russland, Schottland und Schweden veranstaltet hat: Mehr als 500 Bilder zum Thema „Visions and Images of Fascination“ wurden eingereicht. Die zehn besten Fotos finden Sie ab Seite 28. Viel Freude beim Lesen wünscht Ihnen im Namen des Redaktionsteams Evelyn Runge
description: Junge Akademie Magazin, vol. 16
Embedding Information onto a Dynamical System
Creators: name: Manjunath, G
Publisher: name: arXiv
Year: 2021
Subjects: subject: Dynamical Systems (math.DS)
subject: Machine Learning (cs.LG)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences

description: The celebrated Takens' embedding theorem concerns embedding an attractor of a dynamical system in a Euclidean space of appropriate dimension through a generic delay-observation map. The embedding also establishes a topological conjugacy. In this paper, we show how an arbitrary sequence can be mapped into another space as an attractive solution of a nonautonomous dynamical system. Such mapping also entails a topological conjugacy and an embedding between the sequence and the attractive solution spaces. This result is not a generalization of Takens embedding theorem but helps us understand what exactly is required by discrete-time state space models widely used in applications to embed an external stimulus onto its solution space. Our results settle another basic problem concerning the perturbation of an autonomous dynamical system. We describe what exactly happens to the dynamics when exogenous noise perturbs continuously a local irreducible attracting set (such as a stable fixed point) of a discrete-time autonomous dynamical system.
Moho and uppermost mantle structure in the Alpine area from S-to-P converted waves
Creators: name: Kind, Rainer
name: Schmid, Stefan M.
name: Yuan, Xiaohui
name: Heit, Benjamin
name: Meier, Thomas
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Alpine area
subject: Moho depression
subject: uppermost mantle structure
subject: 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie::550 Geowissenschaften

description: In the frame of the AlpArray project we analyse teleseismic data from permanent and temporary stations of the Alpine region to study seismic discontinuities down to about 140 km depth. We average broadband teleseismic S-waveform data to retrieve S-to-P converted signals from below the seismic stations. In order to avoid processing artefacts, no deconvolution or filtering is applied, and S arrival times are used as reference for stacking. We show a number of north–south and east-west profiles through the Alpine area. The Moho signals are always seen very clearly, and negative velocity gradients below the Moho depth are also visible in a number of profiles. A Moho depression is visible along larger parts of the Alpine chain. It reaches its largest depth of 60 km beneath the Tauern Window. However, the Moho depression ends abruptly near about 13∘ E below the eastern Tauern Window. This Moho depression may represent the crustal trench, where the Eurasian lithosphere is subducted below the Adriatic lithosphere. East of 13∘ E an important along-strike change occurs; the image of the Moho changes completely. No Moho deepening is found in this easterly region; instead the Moho bends up along the contact between the European and the Adriatic lithosphere all the way to the Pannonian Basin. An important along-strike change was also detected in the upper mantle structure at about 14∘ E. There, the lateral disappearance of a zone of negative velocity gradient in the uppermost mantle indicates that the S-dipping European slab laterally terminates east of the Tauern Window in the axial zone of the Alps. The area east of about 13∘ E is known to have been affected by severe late-stage modifications of the structure of crust and uppermost mantle during the Miocene when the ALCAPA (Alpine, Carpathian, Pannonian) block was subject to E-directed lateral extrusion.
title: A Guide to Failure
Creators: name: Akademie, Die
Publisher: name: MyCoRe Community
Year: 2013
Subjects: subject: Nachhaltigkeit
subject: Wirtschaftssoziologie
subject: Bildungsforschung
subject: Risikoforschung
subject: Entscheidungsprozesse
subject: Visions and Images of Fascination
subject: Ethikkonflikte
subject: Jonge Academie
subject: 000

description: If you fail, you have been unsuccessful, not fulfilled the expectations you or others had of you, have not reached your goal or have had to forego your wishes or dreams. Usually, failure has a negative connotation. But why is that? The answers given by members of the Junge Akademie (JA) in the dossier on “Failure” are amazingly positive. ‘Failure shows us the way to many other better questions,’ says Emanuel Towfigh, and according to Robert Wolf: ‘failure is part of our daily life.’ The idea for a dossier on “Failure” evolved during an ideas workshop in Weimar in winter 2012. Is self-determined failure a better kind of failure? Do you have to be clever to fail? Have you failed in academia if you do not get a professorship? In the dossier, we could only address some of the many questions. Members of the RG Sustainability investigated the successes and failures of sustainability in the context of fi nance, ecology and academia. The pieces by the economist Moritz Schularick, and the sociologist Magdalena Nowicka focus on how differently systems and individuals deal with (apparent) failure. Failure is related to social norms, which is why failure is often reframed in narratives. As the risk researcher Wolfgang Gaissmaier points out, biographies contain ‘the things that worked’ – and that, in comparison with the things that did not work, is not so very much. In the second part of this issue you will find, as usual, reports on the various research and project groups at the Junge Akademie. The very first photo competition to be run by the Junge Akademie in collaboration with partners from the Netherlands, Russia, Scotland and Sweden was a huge success. More than 500 photos were submitted on the theme of ‘Visions and Images of Fascination.’ Turn to p. 28 to view the top ten images. The editorial team and I hope you’ll enjoy reading our magazine! Evelyn Runge
description: Junge Akademie Magazin, vol. 16
Phenomenology of GUT-less Supersymmetry Breaking
Creators: name: Ellis, John
name: Olive, Keith A.
name: Sandick, Pearl
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Astrophysics (astro-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We study models in which supersymmetry breaking appears at an intermediate scale, M_{in}, below the GUT scale. We assume that the soft supersymmetry-breaking parameters of the MSSM are universal at M_{in}, and analyze the morphology of the constraints from cosmology and collider experiments on the allowed regions of parameter space as M_{in} is reduced from the GUT scale. We present separate analyses of the (m_{1/2},m_0) planes for tan(beta)=10 and tan(beta)=50, as well as a discussion of non-zero trilinear couplings, A_0. Specific scenarios where the gaugino and scalar masses appear to be universal below the GUT scale have been found in mirage-mediation models, which we also address here. We demand that the lightest neutralino be the LSP, and that the relic neutralino density not conflict with measurements by WMAP and other observations. At moderate values of M_{in}, we find that the allowed regions of the (m_{1/2},m_0) plane are squeezed by the requirements of electroweak symmetry breaking and that the lightest neutralino be the LSP, whereas the constraint on the relic density is less severe. At very low M_{in}, the electroweak vacuum conditions become the dominant constraint, and a secondary source of astrophysical cold dark matter would be necessary to explain the measured relic density for nearly all values of the soft SUSY-breaking parameters and tan(beta). We calculate the neutralino-nucleon cross sections for viable scenarios and compare them with the present and projected limits from direct dark matter searches.
description: 35 pages, 9 figures; typos corrected, references added
Out-of-Scope Domain and Intent Classification through Hierarchical Joint Modeling
Creators: name: Liu, Pengfei
name: Li, Kun
name: Meng, Helen
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences

description: User queries for a real-world dialog system may sometimes fall outside the scope of the system's capabilities, but appropriate system responses will enable smooth processing throughout the human-computer interaction. This paper is concerned with the user's intent, and focuses on out-of-scope intent classification in dialog systems. Although user intents are highly correlated with the application domain, few studies have exploited such correlations for intent classification. Rather than developing a two-stage approach that first classifies the domain and then the intent, we propose a hierarchical multi-task learning approach based on a joint model to classify domain and intent simultaneously. Novelties in the proposed approach include: (1) sharing supervised out-of-scope signals in joint modeling of domain and intent classification to replace a two-stage pipeline; and (2) introducing a hierarchical model that learns the intent and domain representations in the higher and lower layers respectively. Experiments show that the model outperforms existing methods in terms of accuracy, out-of-scope recall and F1. Additionally, threshold-based post-processing further improves performance by balancing precision and recall in intent classification.
description: Published in the 12th International Workshop on Spoken Dialog System Technology (IWSDS),2021
A GAN-Like Approach for Physics-Based Imitation Learning and Interactive Character Control
Creators: name: Xu, Pei
name: Karamouzas, Ioannis
Publisher: name: arXiv
Year: 2021
Subjects: subject: Graphics (cs.GR)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: We present a simple and intuitive approach for interactive control of physically simulated characters. Our work builds upon generative adversarial networks (GAN) and reinforcement learning, and introduces an imitation learning framework where an ensemble of classifiers and an imitation policy are trained in tandem given pre-processed reference clips. The classifiers are trained to discriminate the reference motion from the motion generated by the imitation policy, while the policy is rewarded for fooling the discriminators. Using our GAN-based approach, multiple motor control policies can be trained separately to imitate different behaviors. In runtime, our system can respond to external control signal provided by the user and interactively switch between different policies. Compared to existing methods, our proposed approach has the following attractive properties: 1) achieves state-of-the-art imitation performance without manually designing and fine tuning a reward function; 2) directly controls the character without having to track any target reference pose explicitly or implicitly through a phase state; and 3) supports interactive policy switching without requiring any motion generation or motion matching mechanism. We highlight the applicability of our approach in a range of imitation and interactive control tasks, while also demonstrating its ability to withstand external perturbations as well as to recover balance. Overall, our approach generates high-fidelity motion, has low runtime cost, and can be easily integrated into interactive applications and games.
description: Proceedings of the 20th ACM SIGGRAPH/Eurographics Symposium on Computer Animation. Project webpage: https://motion-lab.github.io/ICCGAN