cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Reexamination of Cosmic-Ray Ionization Rate in Protoplanetary Disks with Sheared Magnetic Fields
Creators: name: Fujii, Yuri
name: Kumura, Shigeo
Publisher: name: Zenodo
Year: 2023

description: The magnetic fields in protoplanetary disk are stretched to the azimuthal directions due to the velocity shear. Thus, the cosmic rays entering into the disk need to detour while propagating to the midplane. However, most of the previous studies assume that cosmic rays travel to the midplane straightly from the vertical direction.
 We investigate the effects of magnetic-field configurations on the ionization rate by cosmic rays in protoplanetary disks. First, we consider cosmic-ray propagation from the interstellar medium (ISM) to the protoplanetary disks in the case that magnetic fields threading the protoplanetary disk are connected to its parent molecular cloud, and show that the cosmic-ray density around the disk should be 4 times lower than the isotropic ISM value. Then, we compute the attenuation of cosmic rays in protoplanetary disks. Our results show that the detouring effectively enhances the column density by about two orders of magnitude. We employ a typical ionization rate by cosmic rays in diffuse ISM, which is considered too high to be consistent with observations of protoplanetary disks, and find that the cosmic rays are significantly shielded at the midplane.
 In the case of the disk around IM Lup, the midplane ionization rate is very low for the inner to ~100 au, while the value is as large as a diffuse ISM in the outer radii. Our results are consistent with the recent ALMA observation that indicates the radial gradient in the cosmic-ray ionization rate. The high ionization rate in the outer radii of disks may activate the magnetorotational instability that was thought to be suppressed due to ambipolar diffusion. These results will have a strong influence on the dynamical and chemical evolutions of protoplanetary disks.
Could The Stellar Magnetic Field Explain The Structures In The Au Mic Debris Disk?
Creators: name: Sezestre, Élie
name: Augereau, Jean-Charles
Publisher: name: Zenodo
Year: 2016

description: Recent SPHERE and reprocessed HST images of the edge-on AU Mic debris disk have revealed arch-like structures moving away from the star on unbound trajectories. No model in the literature can readily explain these features. Here,

we explore the effect of the large-scale, stellar magnetic field on the dust dynamics. We show that our study may place constraints on the dust production location.
Accurate modelling of the Lyman-$α$ coupling for the 21-cm signal, observability with NenuFAR and SKA
Creators: name: Semelin, Benoit
name: Mériot, Romain
name: Mertens, Florent
name: Koopmans, Léon V. E.
name: Aubert, Dominique
name: Barkana, Rennan
name: Fialkov, Anastasia
name: Munshi, Satyapan
name: Ocvirk, Pierre
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The measurement of the $21$ cm signal from the Cosmic Dawn is a major goal for several existing and upcoming radio interferometers such as NenuFAR and the SKA. During this era before the beginning of the Epoch of Reionization, the signal is more difficult to observe due to brighter foregrounds but reveals additional information on the underlying astrophysical processes encoded in the spatial fluctuations of the spin temperature of hydrogen. To interpret future measurements, controlling the level of accuracy of the Lyman-$α$ flux modelling is mandatory. In this work, we evaluate the impact of various approximations that exist in the main fast modelling approach compared to the results of a costly full radiative transfer simulation. The fast SPINTER code, presented in this work, computes the Lyman-$α$ flux including the effect of wing scatterings for an inhomogeneous emissivity field, but assuming an otherwise homogeneous expanding universe. The LICORICE code computes the full radiative transfer in the Lyman-$α$ line without any substantial approximation. We find that the difference between homogeneous and inhomogeneous gas density and temperature is very small for the computed flux. On the contrary, neglecting the effect of gas velocities produces a significant change in the computed flux. We identify the causes (mainly Doppler shifts due to velocity gradients) and quantify the magnitude of the effect in both an idealised setup and a realistic cosmological situation. We find that the amplitude of the effect, up to a factor of $\sim 2$ on the $21$ cm signal power spectrum on some scales (depending on both other model parameters and the redshift), can be easily discriminated with an SKA-like survey and already be approached, particularly for exotic signals, by the ongoing NenuFAR Cosmic Dawn Key Science Program.
description: 14 pages, accepted for publication in A&A
Bistability and chaos in Taylor-Green dynamo
Creators: name: Yadav, Rakesh
name: Verma, Mahendra K.
name: Wahi, Pankaj
Publisher: name: arXiv
Year: 2011
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Using direct numerical simulations we study dynamo action under the Taylor-Green forcing with Prandtl number less than one. We observe bistability with a weak magnetic field branch and a strong magnetic field branch. Both the dynamo branches undergo subcritical dynamo transition. We also observe host of dynamo states including constant, periodic, quasiperiodic, and chaotic magnetic fields. One of the chaotic state originates through a quasiperiodic route with phase locking, while another chaotic attractor appears to follow Newhouse-Ruelle-Takens route to chaos. We also observe intermittent transitions among quasiperiodic and chaotic states for a given Taylor-Green forcing.
description: 8 pages, 10 figures
Dynamic flows and stocks of plastics in the United States and pathways towards zero plastic pollution by 2050
Creators: name: Kan, Mengqing
Publisher: name: My University
Year: 2021
Subjects: plastic pollution reduction
scenario analysis
plastic waste

description: The United States (U.S.) is the second-largest national consumer of plastics in the world, which directly leads to a large amount of plastic waste. Due to low recycling and incineration rates in the U.S., 53% of plastic waste was discarded (landfilled or mismanaged) in 2018. Scientific studies have proved that pollution from discarded plastics has a significant negative impact on the environment. This study aims to explore feasible pathways for the U.S. to achieve zero plastic pollution by 2050. This study first developed a dynamic material flow analysis (MFA) model to assess flows and stocks of nine commonly used plastic polymers in seven commodity sectors with five end-of-life pathways in the U.S. for almost seven decades (1950 – 2018). The results show that national plastic pollution increased from 176 thousand metric tons in 1950 to 34,393 thousand metric tons in 2018. Plastic packaging contributed the most to plastic pollution because it has a shorter lifespan and a higher discard rate compared with plastics in other sectors. This study also developed six scenarios to explore pathways of plastic pollution reduction from 2019 to 2050 through seven strategies including 1) adapting a national plastic grocery bag ban, 2) reducing plastic consumption, 3) improving the lifespan of plastic products, 4) increasing waste recycling rate, 5) abandoning waste export, 6) avoiding mismanaged waste leakage, and 7) increasing waste incineration rate to utilize waste resources. Even though each strategy can reduce plastic pollution to different extents, the U.S. cannot achieve the zero plastic pollution target by 2050 through implementing one strategy solely. Thus, a combined scenario that implementing multiple strategies would help the U.S. to achieve zero plastic pollution.
Decision aids that facilitate elements of shared decision making in chronic illnesses: A systematic review
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2019
Subjects: Chronic illnesses
Decision aids
Shared decision making

description: © 2019 The Author(s). Background: Shared decision making (SDM) is a patient-centered approach in which clinicians and patients work together to find and choose the best course of action for each patient's particular situation. Six SDM key elements can be identified: situation diagnosis, choice awareness, option clarification, discussion of harms and benefits, deliberation of patient preferences, and making the decision. The International Patient Decision Aid Standards (IPDAS) require that a decision aid (DA) support these key elements. Yet, the extent to which DAs support these six key SDM elements and how this relates to their impact remain unknown. Methods: We searched bibliographic databases (from inception until November 2017), reference lists of included studies, trial registries, and experts for randomized controlled trials of DAs in patients with cardiovascular, or chronic respiratory conditions or diabetes. Reviewers worked in duplicate and independently selected studies for inclusion, extracted trial, and DA characteristics, and evaluated the quality of each trial. Results: DAs most commonly clarified options (20 of 20; 100%) and discussed their harms and benefits (18 of 20; 90%; unclear in two DAs); all six elements were clearly supported in 4 DAs (20%). We found no association between the presence of these elements and SDM outcomes. Conclusions: DAs for selected chronic conditions are mostly designed to transfer information about options and their harms and benefits. The extent to which their support of SDM key elements relates to their impact on SDM outcomes could not be ascertained. Systematic review registration: PROSPERO registration number: CRD42016050320.
Transport properties in liquids from first principles: the case of liquid water and liquid Argon
Creators: name: Silvestrelli, Pier Luigi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: Shear and bulk viscosity of liquid water and Argon are evaluated from first principles in the Density Functional Theory (DFT) framework, by performing Molecular Dynamics simulations in the NVE ensemble and using the Kubo-Greenwood equilibrium approach. Standard DFT functional is corrected in such a way to allow for a reasonable description of van der Waals (vdW) effects. For liquid Argon the thermal conductivity has been also calculated. Concerning liquid water, to our knowledge this is the first estimate of the bulk viscosity and of the shear-viscosity/bulk-viscosity ratio from first principles. By analyzing our results we can conclude that our first-principles simulations, performed at a nominal average temperature of 366 K to guarantee that the systems is liquid-like, actually describe the basic dynamical properties of liquid water at about 330 K. In comparison with liquid water, the normal, monatomic liquid Ar is characterized by a much smaller bulk-viscosity/shear-viscosity ratio (close to unity) and this feature is well reproduced by our first-principles approach which predicts a value of the ratio in better agreement with experimental reference data than that obtained using the empirical Lennard-Jones potential. The computed thermal conductivity of liquid Argon is also in good agreement with the experimental value.
description: 14 figures
The experience of Christian contemplative practice in helping professionals
Creators: name: Rogers, Eleanor
Publisher: name: University of British Columbia
Year: 2010

description: Current literature in the field of counselling psychology shows a great deal of interest in spirituality, meditation techniques, and how these may be more fully included in counselling practice. There are very few studies that examine contemplative practices such as Christian Centering Prayer, and very few that look at professionals who hold these practices. The purpose of this study is to explore the experiences of people in helping professions who self-identify as having a Christian contemplative practice that includes Centering Prayer. By exploring these people’s experience of their contemplative practice in relation to their personal and professional life, the study reveals an area of counsellor development and professional practice that is rarely discussed. Hermeneutic phenomenology was used, and eight people from eight different professions were interviewed. Seven themes emerged from the interviews: (a) Changes in self-understanding and/or relationship with God, (b) Skills and learning related to thoughts and emotions, (c) Changes in personal relationships, (d) Quality of client and professional relationships, (e) Getting self out of the way, (f) Openness to others — sense of universality, and (g) Embracing life, mystery, and change. The study promotes greater awareness and understanding of contemplative practice and how its teachings relate to counselling and psychotherapy. As well, it offers insights into how these professionals integrate an understanding of spirituality into their work. Implications for practice and recommendations for further research are suggested.
Insight on Hole-Hole Interaction and Magnetic Order from Dichroic Auger-Photoelectron Coincidence Spectra
Creators: name: Cini, Michele
name: Perfetto, Enrico
name: Gotter, Roberto
name: Offi, Francesco
name: Ruocco, Alessandro
name: Stefani, Giovanni
Publisher: name: arXiv
Year: 2011
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The absence of sharp structures in the core-valence-valence Auger line shapes of partially filled bands has severely limited the use of electron spectroscopy in magnetic crystals and other correlated materials. Here by a novel interplay of experimental and theoretical techniques we achieve a combined understanding of the Photoelectron, Auger %$M_{23}M_{45}M_{45}$ and Auger-Photoelectron Coincidence Spectra (APECS) of CoO. This is a prototype antiferromagnetic material in which the recently discovered Dichroic Effect in Angle Resolved (DEAR) APECS reveals a complex pattern in the strongly correlated Auger line shape. A calculation of the \textit{unrelaxed} spectral features explains the pattern in detail, labeling the final states by the total spin. The present theoretical analysis shows that the dichroic effect arises from a spin-dependence of the angular distribution of the photoelectron-Auger electron pair detected in coincidence, and from the selective power of the dichroic technique in assigning different weights to the various spin components. Since the spin-dependence of the angular distribution exists in the antiferromagnetic state but vanishes at the Néel temperature, the DEAR-APECS technique detects the phase transition from its local effects, thus providing a unique tool to observe and understand magnetic correlations in such circumstances, where the usual methods (neutron diffraction, specific heat measurements) are not applicable.
description: Accepted by: Physical Review Letters
Implementing FAIR and open hardware (Open.Make II grant application)
Creators: name: Colomb, Julien
name: Mies, Robert
name: Maxeiner, Moritz
name: Larkum, Matthew
name: Ritter, Petra
name: Jochem, Roland
name: Landgraf, Tim
Publisher: name: Zenodo
Year: 2023
Subjects: open hardware
open source hardware
infrastructure

description: The open science hardware community has identified a lack of recognition of research hardware de- velopers and their work as a main bottleneck towards broader adoption of open hardware in academia. Open.Make II aims to address this issue by promoting the recognition of (open) research hardware as a valuable research output. In this project, we will focus on bridging this gap across various disciplines that involve the use of hardware, ranging from biology to arts to machine tools. Our vision is to gradually build an open hardware centre of competence (CoC) that integrates and connects expertise within and beyond the BUA. Building on the insights from the Open.Make project, Open.Make II takes a socio-technical ap- proach to cultivate a recognised community of professional open hardware developers and makers in the BUA. While Open.Make I primarily focused on understanding the requirements for improving the open hardware space, we will now build on that by combining, consolidating, and extending the community’s tools for documenting, reviewing, and archiving hardware projects. The emanating technical foundation for an open hardware publication ecosystem will be embedded into novel infrastructure of the envisaged CoC: We will provide support to the community through dedicated spaces, expert advice, structured ed- ucational programs, and extensive networking opportunities. In conclusion, Open.Make II is poised to make a significant impact by addressing the recognition gap faced by research hardware developers. By building an open hardware community within the BUA, we will bring together diverse expertise, create opportunities for collaboration, and drive the recognition of research hardware as a valuable research out- put. Through our inclusive approach bringing together all four BUA members and our focus on building robust recognition mechanisms, we aim to empower open hardware engineers, foster interdisciplinary collaboration, and advance scientific research on the national and international level.
description: JC and RM designed the initial plan;  JC wrote the first draft;  RM, MM and TL expanded the idea and reviewed the text; all authors agreed on this submitted version of the grant.
Charge collection and efficiency measurements of the TJ-Monopix2 DMAPS in 180$\,$nm CMOS technology
Creators: name: Bespin, Christian
name: Caicedo, Ivan
name: Dingfelder, Jochen
name: Hemperek, Tomasz
name: Hirono, Toko
name: Hügging, Fabian
name: Krüger, Hans
name: Moustakas, Konstantinos
name: Pernegger, Heinz
name: Riedler, Petra
name: Schall, Lars
name: Snoeys, Walter
name: Wermes, Norbert
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: Monolithic CMOS pixel detectors have emerged as competitive contenders in the field of high-energy particle physics detectors. By utilizing commercial processes they offer high-volume production of such detectors. A series of prototypes has been designed in a 180$\,$nm Tower process with depletion of the sensor material and a column-drain readout architecture. The latest iteration, TJ-Monopix2, features a large 2$\,$cm x 2$\,$cm matrix consisting of 512 x 512 pixels with 33.04$\,$um pitch. A small collection electrode design aims at low power consumption and low noise while the radiation tolerance for high-energy particle detector applications needs extra attention. With a goal to reach radiation tolerance to levels of $10^{15}\,1\,$MeV n$_\text{eq}\,$cm$^{-2}$ of NIEL damage a modification of the standard process has been implemented by adding a low-dosed n-type silicon implant across the pixel in order to allow for homogeneous depletion of the sensor volume. Recent lab measurements and beam tests were conducted for unirradiated modules to study electrical characteristics and hit detection efficiency.
description: Conference proceedings for PIXEL2022 conference, submitted to PoS
Stretched or noded orbital densities and self-interaction correction in density functional theory
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2019
Subjects: physics.chem-ph
cond-mat.mtrl-sci
physics.atm-clus

description: © 2019 Author(s). Semilocal approximations to the density functional for the exchange-correlation energy of a many-electron system necessarily fail for lobed one-electron densities, including not only the familiar stretched densities but also the less familiar but closely related noded ones. The Perdew-Zunger (PZ) self-interaction correction (SIC) to a semilocal approximation makes that approximation exact for all one-electron ground- or excited-state densities and accurate for stretched bonds. When the minimization of the PZ total energy is made over real localized orbitals, the orbital densities can be noded, leading to energy errors in many-electron systems. Minimization over complex localized orbitals yields nodeless orbital densities, which reduce but typically do not eliminate the SIC errors of atomization energies. Other errors of PZ SIC remain, attributable to the loss of the exact constraints and appropriate norms that the semilocal approximations satisfy, suggesting the need for a generalized SIC. These conclusions are supported by calculations for one-electron densities and for many-electron molecules. While PZ SIC raises and improves the energy barriers of standard generalized gradient approximations (GGAs) and meta-GGAs, it reduces and often worsens the atomization energies of molecules. Thus, PZ SIC raises the energy more as the nodality of the valence localized orbitals increases from atoms to molecules to transition states. PZ SIC is applied here, in particular, to the strongly constrained and appropriately normed (SCAN) meta-GGA, for which the correlation part is already self-interaction-free. This property makes SCAN a natural first candidate for a generalized SIC.
Long-range quenched bond disorder in the bi-dimensional Potts model
Creators: name: Chippari, Francesco
name: Picco, Marco
name: Santachiara, Raoul
Publisher: name: arXiv
Year: 2023
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the bi-dimensional $q$-Potts model with long-range bond correlated disorder. Similarly to [C. Chatelain, Phys. Rev. E 89, 032105], we implement a disorder bimodal distribution by coupling the Potts model to auxiliary spin-variables, which are correlated with a power-law decaying function. The universal behaviour of different observables, especially the thermal and the order-parameter critical exponents, are computed by Monte-Carlo techniques for $q=1,2,3$-Potts models for different values of the power-law decaying exponent $a$. On the basis of our conclusions, which are in agreement with previous theoretical and numerical results for $q=1$ and $q=2$, we can conjecture the phase diagram for $q\in [1,4]$. In particular, we establish that the system is driven to a fixed point at finite or infinite long-range disorder depending on the values of $q$ and $a$. Finally, we discuss the role of the higher cumulants of the disorder distribution. This is done by drawning the auxiliary spin-variables from different statistical models. While the main features of the phase diagram depend only on the first and second cumulant, we argue, for the infinite disorder fixed point, that certain universal effects are affected by the higher cumulants of the disorder distribution.
description: 30 pages, 14 figures
Turbulence In Tw Hya: Methods And Limitations
Creators: name: Teague, R.
name: Birnstiel, T.
name: Chapillon, E.
Publisher: name: Zenodo
Year: 2016

description: I will present recent ALMA observations of a depression in CS and CN radial emission around TW Hya, which are co-spatial with a well known dip in scattered light emission. I will discuss the utility of molecular tracers in determining the physical and kinematical conditions around such a features with a view to connect what we observe in scattered light to deeper in the protoplanetary disk.
PhyloToL: A Taxon/Gene-Rich Phylogenomic Pipeline to Explore Genome Evolution of Diverse Eukaryotes
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2019
Subjects: phylogenomic pipeline
high-throughput sequencing data
contamination removal
genome evolution
chromosome mapping

description: © 2019 The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. Estimating multiple sequence alignments (MSAs) and inferring phylogenies are essential for many aspects of comparative biology. Yet, many bioinformatics tools for such analyses have focused on specific clades, with greatest attention paid to plants, animals, and fungi. The rapid increase in high-throughput sequencing (HTS) data from diverse lineages now provides opportunities to estimate evolutionary relationships and gene family evolution across the eukaryotic tree of life. At the same time, these types of data are known to be error-prone (e.g., substitutions, contamination). To address these opportunities and challenges, we have refined a phylogenomic pipeline, now named PhyloToL, to allow easy incorporation of data from HTS studies, to automate production of both MSAs and gene trees, and to identify and remove contaminants. PhyloToL is designed for phylogenomic analyses of diverse lineages across the tree of life (i.e., at scales of >100 My). We demonstrate the power of PhyloToL by assessing stop codon usage in Ciliophora, identifying contamination in a taxon- and gene-rich database and exploring the evolutionary history of chromosomes in the kinetoplastid parasite Trypanosoma brucei, the causative agent of African sleeping sickness. Benchmarking PhyloToL's homology assessment against that of OrthoMCL and a published paper on superfamilies of bacterial and eukaryotic organellar outer membrane pore-forming proteins demonstrates the power of our approach for determining gene family membership and inferring gene trees. PhyloToL is highly flexible and allows users to easily explore HTS data, test hypotheses about phylogeny and gene family evolution and combine outputs with third-party tools (e.g., PhyloChromoMap, iGTP).
Transient stellar collisions as multimessenger probes: Non-thermal-, gravitational wave emission and the cosmic ladder argument
Creators: name: Seoane, Pau Amaro
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In dense stellar clusters like galactic nuclei and globular clusters stellar densities are so high that stars might physically collide with each other. In galactic nuclei the energy and power output can be close, and even exceed, to those from supernovae events. We address the event rate and the electromagnetic characteristics of collisions of main sequence stars (MS) and red giants (RG). We also investigate the case in which the cores form a binary and emit gravitational waves. In the case of RGs this is particularly interesting because the cores are degenerate. We find that MS event rate can be as high as tens per year, and that of RGs one order of magnitude larger. The collisions are powerful enough to mimic supernovae- or tidal disruptions events. We find Zwicky Transient Facility observational data which seem to exhibit the features we describe. The cores embedded in the gaseous debris experience a friction force which has an impact on the chirping mass of the gravitational wave. As a consequence, the two small cores in principle mimic two supermassive black holes merging. However, their evolution in frequency along with the precedent electromagnetic burst and the ulterior afterglow are efficient tools to reveal the impostors. In the particular case of RGs, we derive the properties of the degenerate He cores and their H-burning shells to analyse the formation of the binaries. The merger is such that it can be misclassified with SN Ia events. Because the masses and densities of the cores are so dissimilar in values depending on their evolutionary stage, the argument about standard candles and cosmic ladder should be re-evaluated.
description: 32 pages. Accepted for publication ApJ, minor changes
When Play Turns Lethal: Digital Mediation and Recuperating the (After)lives of Black Girls
Creators: name: Campbell, Casidy
Publisher: name: My University
Year: 2023
Subjects: subject: black girlhood
subject: sexuality
subject: digital technology
subject: representation
subject: social justice
subject: African-American Studies
subject: Women's and Gender Studies
subject: Humanities
subject: FOS: Humanities

description: “When Play Turns Lethal: Digital Mediation and Recuperating the (After)lives of Black Girls,” studies the lives of three black girls murdered in the late twentieth and early twenty-first centuries: Tyisha Miller, Sakia Gunn, and Kenneka Jenkins. Countering African American historians’ propensity to define black girls’ existence through a framework of violence in the archive, I argue that a focus on their daily lives can generate paradigms of justice-seeking that value black girls’ lives and honor them as historical figures. I analyze digital archives, media accounts, and oral history interviews to show how digital media representation and black political movements mounted on their behalf, ironically, flatten their life narratives, agency, and personhood. Through my work, I center narratives of black girls dictated by their life stories instead of fitting them into traditional narratives of resistance or survival. I use Marisa Fuentes’ method of reading along the bias grain to reconstruct Black girls’ life stories and resist the reification of these stories into evidence of violence that can be used to support struggles for social justice. This project challenges utopian ideologies that see technology as a transformative, justice-oriented tool that benefits marginalized people. Instead, having observed black counterpublic discussions within the digital sphere, I show how the infrastructure of digital technologies can distort the aims of social movements by reducing black girls to a form of technology. While black users are aware of some of the shortcomings of technology (“digital divide,” encoded bias, etc.), they often believe in technology’s potential to provide answers, solve problems, and to empower the “powerless” through platform creation. By analyzing the discursive and representational politics at play embedded in the algorithms, networks and code within various media, I show how black internet users work to confront the power dynamics that obscure black girls’ histories while also identifying the intra-racial sexual violence girls encounter. Additionally, I show that navigating the complex calculus of representation within the media complicates grief for some mourners.
Relativistic chiral representation of the $πN$ scattering amplitude II: The pion-nucleon sigma term
Creators: name: Camalich, J. Martin
name: Alarcon, J. M.
name: Oller, J. A.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Lattice (hep-lat)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present a determination of the pion-nucleon sigma-term based on a novel analysis of the $πN$ scattering amplitude in Lorentz covariant baryon chiral perturbation theory renormalized in the extended-on-mass-shell scheme. This amplitude, valid up-to next-to-next-leading order in the chiral expansion, systematically includes the effects of the $Δ(1232)$, giving a reliable description of the phase shifts of different partial wave analyses up to energies just below the resonance region. We obtain predictions on some observables that are within experimental bounds and phenomenological expectations. In particular, we use the center-of-mass energy dependence of the amplitude adjusted with the data above threshold to extract accurately the value of $σ_{πN}$. Our study indicates that the inclusion of modern meson-factory and pionic-atom data favors relatively large values of the sigma term. We report the value $σ_{πN}=59(7)$ MeV.
description: PROCEEDINGS to the 33rd International School of Nuclear Physics "From Quarks and Gluons to Hadrons and Nuclei"-7 pag, 1 fig, 2 tables
Techniques for Pixelated Ambipolar-Sensitive Semiconductor Gamma-Ray Spectrometers
Creators: name: Leak, Charles
Publisher: name: My University
Year: 2021
Subjects: subject: Gamma-ray
subject: Semiconductor
subject: Ambipolar
subject: Pixelated
subject: TlBr
subject: Nuclear Engineering and Radiological Sciences
subject: Engineering

description: Electrode pixelation of CdZnTe gamma-ray spectrometers has historically led to extraordinary energy resolutions for room-temperature operation and has enabled solid-state single-crystal Compton imaging. In this work, pixelated alternative room-temperature semiconductors, especially TlBr, were tested as gamma-ray spectrometers, and digital processing techniques were developed to improve their performance. Pixel ambipolar (electron and hole) sensitivity was observed in TlBr, CdZnTeSe, and CsPbBr3. The effects on traditional depth-reconstruction techniques were studied, and a technique to extract near-pixel position from the pixel waveform shape caused by ambipolar signals was devised. The new technique was implemented on TlBr spectrometers and used to perform an additional energy calibration, improving energy resolutions. This new technique may be used to probe charge transport properties on small length scales, and the improvement in resolution increases the viability of new ambipolar-sensitive spectrometers. Several anomalies such as transient leakage currents, transient bulk electron lifetimes, and transient cathode-localized Auger recombination were observed in TlBr. Some of these anomalies necessitated an increase in trigger thresholds, raising the fraction of single-pixel events experiencing incomplete charge collection. Methods to identify and remove these events were developed accounting for ambipolar signals and applied to TlBr spectrometers, improving photofractions. These methods can be applied to other ambipolar-sensitive spectrometers, increasing their viability. The additional energy calibration and the methods of reducing incomplete charge collection were applied to the best recent 11×11-pixel (22×22×5 mm3) TlBr detector, which improved from 4% uncalibrated to between 1.4% and 2.1% FWHM at 662 keV, dependent on the fraction of the active volume used, and improved the photofraction from 15% to 30%.
On the use of temporal filtering for mitigating galactic synchrotron calibration bias in 21 cm reionization observations
Creators: name: Charles, Ntsikelelo
name: Kern, Nicholas
name: Bernardi, Gianni
name: Bester, Landman
name: Smirnov, Oleg
name: Fagnoni, Nicolas
name: Acedo, Eloy de Lera
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Precision antenna calibration is required for mitigating the impact of foreground contamination in 21 cm cosmological radio surveys. One widely studied source of error is the effect of missing point sources in the calibration sky model; however, poorly understood diffuse galactic emission also creates a calibration bias that can complicate the clean separation of foregrounds from the 21 cm signal. In this work, we present a technique for suppressing this bias with temporal filtering of radio interferometric visibilities observed in a drift-scan mode. We demonstrate this technique on mock simulations of the Hydrogen Epoch of Reionization Array (HERA) experiment. Inspecting the recovered calibration solutions, we find that our technique reduces spurious errors by over an order of magnitude. This improved accuracy approaches the required accuracy needed to make a fiducial detection of the 21 cm signal with HERA, but is dependent on a number of external factors that we discuss. We also explore different types of temporal filtering techniques and discuss their relative performance and tradeoffs.
The prices for for-hire marine fishing trips in the southeastern U.S. collected from websites, 2014-2015.
Creators: name: Carter, David W., 1971-
Publisher: name: U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Science Center, Miami Laboratory.
Year: 2016
Subjects: subject: Charter boat fishing--Prices--South Atlantic States.

description: Information on the prices for for-hire shing services is needed to understand the economics of the industry.1 Prices are used along with data on for-hire shing trip costs and eort to calculate the protability of the sector. Longer price series can be used to estimate demand and supply relationships for for-hire services that help to predict how trip activity is expected to change with proposed regulations. We can learn a lot about how much dierent trip features are worth to anglers by examining the variation in prices for for-hire services over space and time (Carter & Liese 2010). The reason is that prices for for-hire shing trips are determined in the market and vary depending on the demand for trips by anglers and the supply of trips provided by the for-hire industry. Changes in factors that aect the demand and supply of for-hire services will cause for-hire prices to change over time and space. Therefore, data on prices for multiple periods and geographic locations will allow for better economic analyses.
Matrix embeddings on flat $R^3$ and the geometry of membranes
Creators: name: Berenstein, David
name: Dzienkowski, Eric
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We show that given three hermitian matrices, what one could call a fuzzy representation of a membrane, there is a well defined procedure to define a set of oriented Riemann surfaces embedded in $R^3$ using an index function defined for points in $R^3$ that is constructed from the three matrices and the point. The set of surfaces is covariant under rotations, dilatations and translation operations on $R^3$, it is additive on direct sums and the orientation of the surfaces is reversed by complex conjugation of the matrices. The index we build is closely related to the Hanany-Witten effect. We also show that the surfaces carry information of a line bundle with connection on them. We discuss applications of these ideas to the study of holographic matrix models and black hole dynamics.
description: 41 pages, 3 figures, uses revtex4-1. v2: references added, corrected an error in attribution of ideas
Covariate-adjusted survival analyses in propensity-score matched samples: Imputing potential time-to-event outcomes
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2020
Subjects: Propensity score
survival analysis
propensity score matching
matching
Monte Carlo simulations

description: © The Author(s) 2018. Matching on an estimated propensity score is frequently used to estimate the effects of treatments from observational data. Since the 1970s, different authors have proposed methods to combine matching at the design stage with regression adjustment at the analysis stage when estimating treatment effects for continuous outcomes. Previous work has consistently shown that the combination has generally superior statistical properties than either method by itself. In biomedical and epidemiological research, survival or time-to-event outcomes are common. We propose a method to combine regression adjustment and propensity score matching to estimate survival curves and hazard ratios based on estimating an imputed potential outcome under control for each successfully matched treated subject, which is accomplished using either an accelerated failure time parametric survival model or a Cox proportional hazard model that is fit to the matched control subjects. That is, a fitted model is then applied to the matched treated subjects to allow simulation of the missing potential outcome under control for each treated subject. Conventional survival analyses (e.g., estimation of survival curves and hazard ratios) can then be conducted using the observed outcome under treatment and the imputed outcome under control. We evaluated the repeated-sampling bias of the proposed methods using simulations. When using nearest neighbor matching, the proposed method resulted in decreased bias compared to crude analyses in the matched sample. We illustrate the method in an example prescribing beta-blockers at hospital discharge to patients hospitalized with heart failure.
Permeability of phospholipid membrane for small polar molecules determined from osmotic swelling of giant phospholipid vesicles
Creators: name: Peterlin, Primoz
name: Arrigler, Vesna
name: Diamant, Haim
name: Haleva, Emir
Publisher: name: arXiv
Year: 2012
Subjects: subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: A method for determining permeability of phospholipid bilayer based on the osmotic swelling of micrometer-sized giant unilamellar vesicles (GUVs) is presented as an alternative to the two established techniques, dynamic light scattering on liposome suspension, and electrical measurements on planar lipid bilayers. In the described technique, an individual GUV is transferred using a micropipette from a sucrose/glucose solution into an isomolar solution containing the solute under investigation. Throughout the experiment, vesicle cross-section is monitored and recorded using a digital camera mounted on a phase-contrast microscope. Using a least-squares procedure for circle fitting, vesicle radius R is computed from the recorded images of vesicle cross-section. Two methods for determining membrane permeability from the obtained R(t) dependence are described: the first one uses the slope of R(t) for a spherical GUV, and the second one the R(t) dependence around the transition point at which a flaccid vesicle transforms into a spherical one. We demonstrate that both methods give consistent estimates for membrane permeability.
description: 40 pages, 8 figures, to appear in Advances in Planar Lipid Membranes and Liposomes vol. 16
Perdew-Zunger self-interaction correction: How wrong for uniform densities and large-Z atoms?
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2019
Subjects: physics.chem-ph
physics.comp-ph

description: © 2019 Author(s). Semilocal density functionals for the exchange-correlation energy of a many-electron system cannot be exact for all one-electron densities. In 1981, Perdew and Zunger (PZ) subtracted the fully nonlocal self-interaction error orbital-by-orbital, making the corrected functional exact for all collections of separated one-electron densities and making no correction to the exact functional. Although the PZ self-interaction correction (SIC) eliminates many errors of semilocal functionals, it is often worse for equilibrium properties of sp-bonded molecules and solids. Nonempirical semilocal functionals are usually designed to be exact for electron gases of uniform density and, thus, also make 0% error for neutral atoms in the limit of large atomic number Z, but PZ SIC is not so designed. For localized SIC orbitals, we show analytically that the local spin density approximation (LSDA)-SIC correlation energy per electron of the uniform gas in the high-density limit makes an error of -50% in the spin-unpolarized case and -100% in the fully spin-polarized case. Then we extrapolate from the Ne, Ar, Kr, and Xe atoms to estimate the relative errors of the PZ SIC exchange-correlation energies (with localized SIC orbitals) in the limit of large atomic number: about +5.5% for the LSDA-SIC and about -3.5% for nonempirical generalized gradient [Perdew-Burke-Ernzerhof (PBE)-SIC] and meta-generalized gradient strongly constrained and appropriately normed (SCAN)-SIC approximations. The SIC errors are considerably larger than those that have been estimated for LSDA-SIC by approximating the localized SIC orbitals for the uniform gas and may explain the errors of PZ SIC for equilibrium properties, opening the door to a generalized SIC that is more widely accurate.
Modeling Protoplanetary Disk Continuum Surface Brightness :  Inference For High-Resolution Alma Data
Creators: name: Tripathi, Anjali
name: Andrews, Sean
Publisher: name: Zenodo
Year: 2016

description: Millimeter continuum emission from dust in disks provides a key observational constraint on planet formation. However, radio interferometry presents challenges for modeling the dust surface brightness. Previously, the standard approach has used analytic brightness profiles, derived from gas dynamics.  In the ALMA era, modeling now includes ad-hoc complexity to explain features unexplained by simpler analytic models.  To find an appropriate model for high-resolution data, we have developed a flexible method to infer the dust surface brightness. Unlike simple analytic, parametric models, our model is well-suited to highlighting features such as gaps and overdensities – useful in the era of ALMA data.
Bridges between helioseismological and asteroseismological inference
Creators: name: Gough, D. O.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Exactly eighty years ago, a very young Yehudi Menuhin was invited by Bruno Walter to perform Beethoven's violin concerto with the Berlin Philharmonic Orchestra. Walking through the streets of Berlin he was unsure of his way, and asked a passer-by how he could get to the Konzerthaus. The man looked at him, looked down at the violin case that Yehudi was carrying, and said: `Practise, young man, practise'. It was with such advice in their minds, I am sure, that Margarida and Michael have asked me to try to build bridges between helioseismology and asteroseismology. Asteroseismology is new and fresh, and the young scientists who are entering the subject should be full of the expectation of the delights of discovery of untrodden ground. Where should they tread? They should be guided, perhaps, by our mature, well practised, experiences with the Sun.
description: 3 pages
Nuclear response to dark matter signals in Ge and Xe odd-mass targets
Creators: name: Saez, M. M.
name: Civitarese, O.
name: Tarutina, T.
name: Fushimi, K.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Abstract: The interaction of dark matter particles (WIMPs) with the odd-mass $^{73}$Ge and $^{131}$Xe target nuclei ,{ {that is the recoil rates corresponding to the elastic scattering of WIMPs by these nuclei}}, is analysed in the context of the minimal extensions of the SUSY model. The BCS+QRPA technique plus the quasiparticle-phonon coupling scheme is used to describe the nuclear structure part of the calculations. The resulting values for the nuclear spin content of both nuclei are compared to values previously reported in the literature.
First Search for Short-Baseline Neutrino Oscillations at HFIR with PROSPECT
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2018
Subjects: PROSPECT Collaboration 1

description: © 2018 authors. Published by the American Physical Society. This Letter reports the first scientific results from the observation of antineutrinos emitted by fission products of U235 at the High Flux Isotope Reactor. PROSPECT, the Precision Reactor Oscillation and Spectrum Experiment, consists of a segmented 4 ton Li6-doped liquid scintillator detector covering a baseline range of 7-9 m from the reactor and operating under less than 1 m water equivalent overburden. Data collected during 33 live days of reactor operation at a nominal power of 85 MW yield a detection of 25 461±283 (stat) inverse beta decays. Observation of reactor antineutrinos can be achieved in PROSPECT at 5σ statistical significance within 2 h of on-surface reactor-on data taking. A reactor model independent analysis of the inverse beta decay prompt energy spectrum as a function of baseline constrains significant portions of the previously allowed sterile neutrino oscillation parameter space at 95% confidence level and disfavors the best fit of the reactor antineutrino anomaly at 2.2σ confidence level.