cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Mapping of the magnetic field to correct systematic effects in a neutron electric dipole moment experiment
Creators: name: Abel, C.
name: Ayres, N. J.
name: Ban, G.
name: Bison, G.
name: Bodek, K.
name: Bondar, V.
name: Chanel, E.
name: Chiu, P. -J.
name: Clément, B.
name: Crawford, C. B.
name: Daum, M.
name: Emmenegger, S.
name: Ferraris-Bouchez, L.
name: Fertl, M.
name: Flaux, P.
name: Fratangelo, A.
name: Griffith, W. C.
name: Grujić, Z. D.
name: Harris, P. G.
name: Hayen, L.
name: Hild, N.
name: Kasprzak, M.
name: Kirch, K.
name: Knowles, P.
name: Koch, H. -C.
name: Koss, P. A.
name: Kozela, A.
name: Krempel, J.
name: Lauss, B.
name: Lefort, T.
name: Lemière, Y.
name: Mohanmurthy, P.
name: Naviliat-Cuncic, O.
name: Pais, D.
name: Piegsa, F. M.
name: Pignol, G.
name: Prashanth, P. N.
name: Quéméner, G.
name: Rawlik, M.
name: Ries, D.
name: Rebreyend, D.
name: Roccia, S.
name: Rozpedzik, D.
name: Schmidt-Wellenburg, P.
name: Schnabel, A.
name: Severijns, N.
name: Thorne, J. A.
name: Virot, R.
name: Weis, A.
name: Wursten, E.
name: Wyszynski, G.
name: Zejma, J.
name: Zsigmond, G.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: Experiments dedicated to the measurement of the electric dipole moment of the neutron require outstanding control of the magnetic field uniformity. The neutron electric dipole moment (nEDM) experiment at the Paul Scherrer Institute uses a 199Hg co-magnetometer to precisely monitor magnetic field variations. This co-magnetometer, in the presence of field non-uniformity, is responsible for the largest systematic effect of this measurement. To evaluate and correct that effect, offline measurements of the field non-uniformity were performed during mapping campaigns in 2013, 2014 and 2017. We present the results of these campaigns, and the improvement the correction of this effect brings to the neutron electric dipole moment measurement.
The effect of consumer mindfulness on green technology acceptance
Creators: name: Erdogan, Emine
Publisher: name: No Publisher Supplied
Year: 2018

description: This dissertation investigated how consumer mindfulness influences the decision-making process of accepting green technological products. Based on the theory of technology acceptance and bounded rationality, this study examined the concept of mindfulness as an individual difference variable and tested it under the constraining effects of information ambiguity, cognitive overload, and time pressure in the process of consumer’s acceptance of green technological products, specifically high-tech vehicles (Electric Vehicles). Companies in the automotive industry are categorized as reliability seeking organizations. These organizations cannot tolerate even minimum reliability gaps since potential lapses can ultimately threat human life and devastate the firm’s image. Previous research suggested that mindfulness, mostly associated with enhanced attention, active awareness, openness to novelty/new information, and sensitivity to context/multiple perspectives is an essential characteristic of reliability seeking customers. Recent trends in the industry for electrification and automation of cars promise to ensure consumers’ safety and environmental concerns yet create new ambiguities. Using a structural equation modeling methodology, findings of this study indicated that customers’ dispositional mindfulness, normative approach about eco-friendly vehicles, rational decision-making styles, and counter-intuitively cognitive load have positive effects on consumers’ situational mindfulness while information uncertainties, financial risks, and perceived time pressure have adverse impacts on it. Additionally, the study added to the technology acceptance literature by revealing the positive and significant impact of situational mindfulness on both perceived ease of use (effort expectancy) and perceived usefulness of green technology which ultimately drive customers’ intention to use. Furthermore, the study revealed that situational mindfulness mediates the relationships between all of its determinants and consumers’ perceptions (perceived ease of use and perceived usefulness) and consumers’ perceptions mediate the relationships between situational mindfulness and intention to use green technology. Finally, this study tested the moderating effect of consumers’ perceived cognitive load, uncertainty, financial risk, and time pressure on their green technology acceptance process and found partial support for the proposed effects.The ultimate purpose of the study is to improve our understanding of mindfulness and marketing green technological products through expanding the perspective on mindful technology adoption. By considering the impacts of mindfulness on the green technology acceptance process, the study also adds to the innovation and management literature by enabling us to understand better users’ perceptions and intentions of using green technology.
Multivariate Eulerian polynomials and exclusion processes
Creators: name: Brändén, Petter
name: Leander, Madeleine
name: Visontai, Mirkó
Publisher: name: arXiv
Year: 2014
Subjects: subject: Combinatorics (math.CO)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Probability (math.PR)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We give a new combinatorial interpretation of the stationary distribution of the (partially) asymmetric exclusion process on a finite number of sites in terms of decorated alternative trees and colored permutations. The corresponding expressions of the multivariate partition functions are then related to multivariate generalizations of Eulerian polynomials for colored permutations considered recently by N. Williams and the third author, and others. We also discuss stability-- and negative dependence properties satisfied by the partition functions.
description: 13 pages (removed Conjecture 5.8 and updated references)
Mapping the Location and Extent of 2019 Prevent Planting Acres in South Dakota Using Remote Sensing Techniques
Creators: name: Lawal, Afolarin
name: Kerner, Hannah
name: Becker-Reshef, Inbal
name: Meyer, Seth
Publisher: name: MDPI
Year: 2021
Subjects: Landsat 8
flood
Sentinel 1
prevent plant acres

description: The inability of a farmer to plant an insured crop by the policy’s final planting date can pose financial challenges for the grower and cause reduced production for a widely impacted region. Prevented planting is primarily caused by excess moisture or rainfall such as the catastrophic flooding and widespread conditions that prevented active field work in the midwestern region of United States in 2019. While the Farm Service Agency reports the number of such “prevent plant” acres each year at the county scale, field-scale maps of prevent plant fields—which would enable analyses related to assessing and mitigating the impact of climate on agriculture—are not currently available. The aim of this study is to demonstrate a method for mapping likely prevent plant fields based on flood mapping and historical cropland maps. We focused on a study region in eastern South Dakota and created flood maps using Landsat 8 and Sentinel 1 images from 2018 and 2019. We used automatic threshold-based change detection using NDVI and NDWI to accentuate changes likely caused by flooding. The NDVI change detection map showed vegetation loss in the eastern parts of the study area while NDWI values showed increased water content, both indicating possible flooding events. The VH polarization of Sentinel 1 was also particularly useful in identifying potential flooded areas as the VH values for 2019 were substantially lower than those of 2018, especially in the northern part of the study area, likely indicating standing water or reduced biomass. We combined the flood maps from Landsat 8 and Sentinel 1 to form a complete flood likelihood map over the entire study area. We intersected this flood map with a map of fallow pixels extracted from the Cropland Data Layer to produce a map of predicted prevent plant acres across several counties in South Dakota. The predicted figures were within 10% error of Farm Service Agency reports, with low errors in the most affected counties in the state such as Beadle, Hanson, and Hand.
EPR steering in symmetrical Gaussian states
Creators: name: Benech, Eugenia
name: Auyuanet, Adriana
name: Lezama, Arturo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We have explored quantum Einstein-Podolsky-Rosen steering in symmetric two-mode Gaussian states using Gaussian and non-Gaussian measurements. For Gaussian measurements, we show that steering between the output modes of a symmetric beamsplitter is possible regardless of purity when a threshold input-state quadrature variance compression is achieved. Using the non-Gaussian operators introduced in [1] we show that non-Gaussian measurements can outperform Gaussian measurements for symmetrical states. We also analyze the possibility of asymmetric measurements setups made possible by non-Gaussian measurements and provide examples where such asymmetry is optimal for revealing steering. [1] Ji, SW., Lee, J., Park, J. et al. Quantum steering of Gaussian states via non-Gaussian measurements. Sci Rep 6, 29729 (2016). https://doi.org/10.1038/srep29729
description: 9 pages, 6 figures. Addmited for publication on Physical Review A, as a regular article
Synthesis and study of perylene-bridge-anchor derivatives for metal oxides semiconductor sensitization
Creators: name: Fan, Hao
Publisher: name: No Publisher Supplied
Year: 2018

description: Electron transfer at the interface between a photoactive molecule and large-bandgap nanostructured metal oxide (MOn) semiconductors remains at the center of intense research in numerous areas for solar energy conversion. Organic chromophore-bridge-anchor compounds are important to the studies of heterogeneous charge transfer on MOn semiconductors and are widely employed in various photochemistry researches.  In this thesis, we report the synthesis of 2,5-di-tert-butylperylene (DTBuPe) and a series of DTBuPe-bridge-anchor compounds, and study their steady state photochemical properties in solutions as well as on nanostructured metal oxide semiconductor films. The thesis described a practical pathway to synthesize the DTBuPe, and further modification of the DTBuPe framework. Two modification routes were employed; one starting from formylation, which can be followed by reduction, oxidation or other functional group transformation of the aldehyde group. The second route starts from bromination of the framework, followed by various palladium catalyzed cross-coupling reactions. Through these methods, a series of DTBuPe-bridge-anchor derivatives were synthesized.The spectroscopic properties of DTBuPe-bridge-anchor derivatives in solution and bound to nanostructured semiconductor surfaces were also investigated by absorption and emission spectra. 8,11-di-tert-Butylperylene-3-carboxylic acid (DTBuPe-COOH), 3-(8,11-di-tert-Butylperylen-3-yl)propanoic acid (DTBuPe-Prop-COOH),  4-(8,11-di-tert-Butylperylen-3-yl)benzoic acid (DTBuPe-Ph-COOH) and perylene-3-carboxylic acid (Pe-COOH) were bound to both TiO2 and ZrO2 films and characterized by absorption and emission spectra. A comparison of the properties of DTBuPe-bridge-anchor/TiO2 and perylene/TiO2 is made, and the influence of t-butyl spacing group, as well as different bridge units, is investigated. In addition, perylene was functionalized with an azide group (9-(4-azidophenyl)-2,5-di-tert-Butylperylene (DTBuPe-Ph-N3)) for click chemistry. Copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction of DTBuPe-Ph-N3 was successfully performed in solution and on ZnO nanostructured surfaces which was functionalized with propiolic acid in a stepwise functionalization process. The sensitized ZnO surface was characterized by SEM, XPS and TA. The morphology of ZnO nanorod was preserved and strong electronic coupling between sensitizer and semiconductor film was obtained.
Structure-Based and Rational Design of a Hepatitis C Virus Vaccine
Creators: name: Guest, Johnathan D.
name: Pierce, Brian G.
Publisher: name: MDPI
Year: 2021
Subjects: HCV
E1E2
structure-based vaccine design

description: A hepatitis C virus (HCV) vaccine is a critical yet unfulfilled step in addressing the global disease burden of HCV. While decades of research have led to numerous clinical and pre-clinical vaccine candidates, these efforts have been hindered by factors including HCV antigenic variability and immune evasion. Structure-based and rational vaccine design approaches have capitalized on insights regarding the immune response to HCV and the structures of antibody-bound envelope glycoproteins. Despite successes with other viruses, designing an immunogen based on HCV glycoproteins that can elicit broadly protective immunity against HCV infection is an ongoing challenge. Here, we describe HCV vaccine design approaches where immunogens were selected and optimized through analysis of available structures, identification of conserved epitopes targeted by neutralizing antibodies, or both. Several designs have elicited immune responses against HCV in vivo, revealing correlates of HCV antigen immunogenicity and breadth of induced responses. Recent studies have elucidated the functional, dynamic and immunological features of key regions of the viral envelope glycoproteins, which can inform next-generation immunogen design efforts. These insights and design strategies represent promising pathways to HCV vaccine development, which can be further informed by successful immunogen designs generated for other viruses.
Mixed-precision for Linear Solvers in Global Geophysical Flows
Creators: name: Ackmann, Jan
name: Düben, Peter D.
name: Palmer, Tim N.
name: Smolarkiewicz, Piotr K.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Computational Engineering, Finance, and Science (cs.CE)
subject: Numerical Analysis (math.NA)
subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Semi-implicit time-stepping schemes for atmosphere and ocean models require elliptic solvers that work efficiently on modern supercomputers. This paper reports our study of the potential computational savings when using mixed precision arithmetic in the elliptic solvers. The essential components of a representative elliptic solver are run at precision levels as low as half (16 bits), and accompanied with a detailed evaluation of the impact of reduced precision on the solver convergence and the solution quality. A detailed inquiry into reduced precision requires a model configuration that is meaningful but cheaper to run and easier to evaluate than full atmosphere/ocean models. This study is therefore conducted in the context of a novel semi-implicit shallow-water model on the sphere, purposely designed to mimic numerical intricacies of modern all-scale weather and climate (W&C) models with the numerical stability independent on celerity of all wave motions. The governing algorithm of the shallow-water model is based on the non-oscillatory MPDATA methods for geophysical flows, whereas the resulting elliptic problem employs a strongly preconditioned non-symmetric Krylov-subspace solver GCR, proven in advanced atmospheric applications. The classical longitude/latitude grid is deliberately chosen to retain the stiffness of global W&C models posed in thin spherical shells as well as to better understand the performance of reduced-precision arithmetic in the vicinity of grid singularities. Precision reduction is done on a software level, using an emulator. The reduced-precision experiments are conducted for established dynamical-core test-cases, like the Rossby-Haurwitz wave number 4 and a zonal orographic flow. The study shows that selected key components of the elliptic solver, most prominently the preconditioning, can be performed at the level of half precision.
description: 38 pages, 12 figures; to be submitted to the Journal of Computational Physics (JCP)
Dual-ligand luminescent metal-organic frameworks towards environmental remediation efforts
Creators: name: Rudd, Nathan D.
Publisher: name: No Publisher Supplied
Year: 2018

description: Rapid industrialization during the 20th century has left an indelible mark on the global landscape. Often, industrial processes cannot be regulated to match the pace at which nations are developing—infrastructures become more complex without proper management. Contamination of local environments from these operations has plagued ecosystems and can lead to detrimental effects on a larger scale. In recent decades, the development of “green” industrial agendas has diminished pollution and enriched efforts for environmentally sustainable technologies, however this progression does not remediate the contamination that already exists. Functional materials that can detect ultralow concentrations of pollutants are essential before they accumulate and cause extensive damage. Furthermore, dual-performance compounds that sense and extract contaminants would streamline environmental purification efforts and simplify remediation procedures.Luminescent metal-organic frameworks (LMOFs) are a rapidly growing category of functional, crystalline materials useful for a broad range of applications. LMOFs are comprised of single metal ions or clusters linked together through organic ligands. Extended, multidimensional frameworks are formed that boast tunable surfaces and optical properties. The ability to alter porosity and chemical functionalities within the material enhance the effectiveness to interact with specifically targeted analytes. Organic ligands within LMOFs, through the scope of this work, contain aromatic groups that undergo optical emission under specific irradiation. Linker molecules with varying functional moieties are also incorporated into LMOFs. When assembled together, the materials that are produced exhibit altered optical emission profiles through strong guest-host interactions as well as the interplay between the optically-active and functionalized organic ligands. Additionally, enhanced uptake of guest molecules into the LMOF channels highlight the dual-performance of these materials.Overall, this dissertation focuses on the design, synthesis, characterization and application of LMOFs for the luminescence-based sensing and extraction of various inorganic/organic species, important for both contamination remediation and energy-related applications.
Zeno crossovers in the entanglement speed of spin chains with noisy impurities
Creators: name: Chaudhari, Abhijit P.
name: Kelly, Shane P.
name: Valencia-Tortora, Riccardo J.
name: Marino, Jamir
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We use a noisy signal with finite correlation time to drive a spin (dissipative impurity) in the quantum XY spin chain and calculate the dynamics of entanglement entropy of a bipartition of spins, for a stochastic quantum trajectory. We compute the noise averaged entanglement entropy of a bipartition of spins and observe that its speed of spreading decreases at strong dissipation, as a result of the Zeno effect. We recover the Zeno crossover and show that noise averaged entanglement entropy can be used as a proxy for the heating and Zeno regimes. Upon increasing the correlation time of the noise, the location of the Zeno crossover shifts at stronger dissipation, extending the heating regime.
description: 14 pages, 5 figures
Optimal driving of isothermal processes close to equilibrium
Creators: name: Bonança, Marcus V. S.
name: Deffner, Sebastian
Publisher: name: arXiv
Year: 2014
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We investigate how to minimize the work dissipated during nonequilibrium processes. To this end, we employ methods from linear response theory to describe slowly varying processes, i.e., processes operating within the linear regime around quasistatic driving. As a main result we find that the irreversible work can be written as a functional that depends only on the correlation time and the fluctuations of the generalized force conjugated to the driving parameter. To deepen the physical insight of our approach we discuss various self-consistent expressions for the response function, and derive the correlation time in closed form. Finally, our findings are illustrated with several analytically solvable examples.
description: 15 pages, 10 figures, accepted for publication in J. Chem. Phys
Electron-lattice coupling contributions to polarization switching in charge-order-induced ferroelectrics
Creators: name: Qi, Yubo
name: Rabe, Karin M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We carry out first-principles density-functional-theory calculations to elucidate the polarization switching mechanism in charge-ordering-induced ferroelectrics based on the prototypical case of the (SrVO$_3$)$_1$(LaVO$_3$)$_1$ superlattice. We find that lattice relaxation for a specific charge ordering state can "lock" that state in, making non-adiabatic switching to a different CO variant energetically prohibitive, and in some cases, even making the energy barrier for adiabatic switching prohibitively large. We classify charge-ordering materials into two types, polyhedral breathing and off-centering displacement, based on the type of lattice mode most strongly coupled to the charge ordering. We demonstrate that the non-adiabatic electron hopping induced by an external electric field is expected only in off-centering-displacement-type charge-ordering-induced ferroelectrics. This successfully explains the different observed switching behaviors of LuFe$_2$O$_4$ and Fe$_3$O$_4$. These results offer a new understanding of the polarization switching mechanism in charge-ordering-induced ferroelectrics that provides guidance for the design and discovery of charge-ordering-induced ferroelectric materials and suggests a strategy for realizing "electronic ferroelectricity" with polarization switching on electronic rather than lattice time scales.
E-00148-2023_Richani et al_AJPE&M_Supplementary M&M and Results.docx
Creators: name: Gilchrist, Robert
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 310105
subject: Cellular interactions (incl. adhesion, matrix, cell wall)

description: Supplemental Methods and Results and Data for Richani D. et al 2023
Role of Rabi oscillations in radiative states due to the fully absorbing smaller plasmonic nanoparticles
Creators: name: Jain, Kritika
name: Venkatapathi, Murugesan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The modified radiative and non-radiative states due to the weak coupling of an emitter with other resonant objects (Purcell effect), can be recast as a quantum interference of the paths of the photon that define the classical scattering and absorption by the object. When the coupling is stronger, additional paths representing the (Rabi oscillations or) possible re-absorption of the photon from the excited object, by the emitter at ground-state, have to be included in the quantum interference. The effect of these additional Rabi paths of the photon on the radiative states and the efficiency of spontaneous emission, can be approximated using a simple one-loop correction to the weak-coupling approximation. This effect is especially evident in the anomalous enhancements of emission due to extremely small non-scattering (or fully absorbing) metal nanoparticles less than 10 nm in dimensions. Extending these corrections to a collective model of spontaneous emission that includes multiple emitters and such very small metal nanoparticles coupled to each other, the large contribution of Rabi paths to radiative decay in such bulk materials is elucidated.
Active Turbulence
Creators: name: Alert, Ricard
name: Casademunt, Jaume
name: Joanny, Jean-François
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Chaotic Dynamics (nlin.CD)
subject: Pattern Formation and Solitons (nlin.PS)
subject: Biological Physics (physics.bio-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Active fluids exhibit spontaneous flows with complex spatiotemporal structure, which have been observed in bacterial suspensions, sperm cells, cytoskeletal suspensions, self-propelled colloids, and cell tissues. Despite occurring in the absence of inertia, chaotic active flows are reminiscent of inertial turbulence, and hence they are known as active turbulence. Here, we survey the field, providing a unified perspective over different classes of active turbulence. To this end, we divide our review in sections for systems with either polar or nematic order, and with or without momentum conservation (wet/dry). Comparing to inertial turbulence, we highlight the emergence of power-law scaling with either universal or non-universal exponents. We also contrast scenarios for the transition from steady to chaotic flows, and we discuss the absence of energy cascades. We link this feature to both the existence of intrinsic length scales and the self-organized nature of energy injection in active turbulence, which are fundamental differences with inertial turbulence. We close by outlining the emerging picture, remaining challenges, and future directions.
description: Review for Annu. Rev. Condens. Matter Phys
Asteroid families classification: exploiting very large data sets
Creators: name: Milani, Andrea
name: Cellino, Alberto
name: Knezevic, Zoran
name: Novakovic, Bojan
name: Spoto, Federica
name: Paolicchi, Paolo
Publisher: name: arXiv
Year: 2013
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The number of asteroids with accurately determined orbits increases fast. The catalogs of asteroid physical observations have also increased, although the number of objects is still smaller than in the orbital catalogs. We developed a new approach to the asteroid family classification by combining the Hierarchical Clustering Method (HCM) with a method to add new members to existing families. This procedure makes use of the much larger amount of information contained in the proper elements catalogs, with respect to classifications using also physical observations for a smaller number of asteroids. Our work is based on the large catalog of the high accuracy synthetic proper elements (available from AstDyS). We first identify a number of core families; to these we attribute the next layer of smaller objects. Then, we remove all the family members from the catalog, and reapply the HCM to the rest. This gives both halo families which extend the core families and new independent families, consisting mainly of small asteroids. These two cases are discriminated by another step of attribution of new members and by merging intersecting families. By using information from absolute magnitudes, we take advantage of the larger size range in some families to analyze their shape in the proper semimajor axis vs. inverse diameter plane. This leads to a new method to estimate the family age (or ages). The results from the previous steps are then analyzed, using also auxiliary information on physical properties including WISE albedos and SDSS color indexes. This allows to solve some difficult cases of families overlapping in the proper elements space but generated by different collisional events. We analyze some examples of cratering families (Massalia, Vesta, Eunomia) which show internal structures, interpreted as multiple collisions. We also discuss why Ceres has no family.
Phonon contribution to the entropy of hard sphere crystals
Creators: name: Elser, Veit
Publisher: name: arXiv
Year: 2014
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Comparing the entropies of hard spheres in the limit of close packing, for different stacking sequences of the hexagonal layers, has been a challenge because the differences are so small. Here we present a new method based on a "sticky-sphere" model by which the system interpolates between hard spheres in one limit and a harmonic crystal in the other. For the fcc and hcp stackings we have calculated the entropy difference in the harmonic (sticky) limit, as well as the differences in the free energy change upon removing the stickiness in the model. The former, or phonon entropy, accounts for most of the entropy difference. Our value for the net entropy difference, 0.001164(8) k_B per sphere, is in excellent agreement with the best previous estimate by Mau and Huse [Phys. Rev. E 59, 4396 (1999)].
description: 6 pages, 3 figures
Spin-helical detection in a semiconductor quantum device with ferromagnetic contacts
Creators: name: Yang, Zedong
name: Crowell, Paul A.
name: Pribiag, Vlad S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Spin-helical states, which arise in quasi-one-dimensional (1D) channels with spin-orbital (SO) coupling, underpin efforts to realize topologically-protected quantum bits based on Majorana modes in semiconductor nanowires. Detecting helical states is challenging due to non-idealities present in real devices. Here we show by means of tight-binding calculations that by using ferromagnetic contacts it is possible to detect helical modes with high sensitivity even in the presence of realistic device effects, such as quantum interference. This is possible because of the spin-selective transmission properties of helical modes. In addition, we show that spin-polarized contacts provide a unique path to investigate the spin texture and spin-momentum locking properties of helical states. Our results are of interest not only for the ongoing development of Majorana qubits, but also as for realizing possible spin-based quantum devices, such as quantum spin modulators and interconnects based on spin-helical channels.
description: 7 pages, 5 figures
Using Multi-Resolution Satellite Data to Quantify Land Dynamics: Applications of PlanetScope Imagery for Cropland and Tree-Cover Loss Area Estimation
Creators: name: Pickering, Jeffrey
name: Tyukavina, Alexandra
name: Khan, Ahmad
name: Potapov, Peter
name: Adusei, Bernard
name: Hansen, Matthew C.
name: Lima, André
Publisher: name: MDPI
Year: 2021
Subjects: PlanetScope imagery
Pakistan
wheat
Peru
tree-cover loss
degradation
land-cover
sampling

description: The Planet constellation of satellites represents a significant advance in the availability of high cadence, high spatial resolution imagery. When coupled with a targeted sampling strategy, these advances enhance land-cover and land-use monitoring capabilities. Here we present example regional and national-scale area-estimation methods as a demonstration of the integrated and efficient use of mapping and sampling using public medium-resolution (Landsat) and commercial high resolution (PlanetScope) imagery. Our proposed method is agnostic to the geographic region and type of land cover and change, which is demonstrated by applying the method across two very different geographies and thematic classes. Wheat extent is estimated in Punjab, Pakistan, for the 2018/2019 growing season, and tree-cover loss area is estimated over Peru for 2017 and 2018. We used a time series of PlanetScope imagery to classify a sample of 5 × 5 km blocks for each region and produce area estimates of 55,947 km2 (±9.0%) of wheat in Punjab and 5398 km2 (±9.1%) of tree-cover loss in Peru. We also demonstrate the use of regression estimation utilizing population information from Landsat-based maps to reduce standard errors of the sample-based estimates. Resulting regression estimates have SEs of 3.6% and 5.1% for Pakistan and Peru, respectively. The combination of daily global coverage and high spatial resolution of Planet imagery improves our ability to monitor crop phenology and capture ephemeral tree-cover loss and degradation dynamics, while Landsat-based maps provide wall-to-wall information to target the sample and increase precision of the estimates through the use of regression estimation.
Finite pulse effects on $e^{+}e^{-}$ pair creation from strong electric fields
Creators: name: Taya, Hidetoshi
name: Fujii, Hirotsugu
name: Itakura, Kazunori
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We investigate electron-positron pair creation from the vacuum in a pulsed electric background field. Employing the Sauter-type pulsed field $E(t)=E_0 {\rm sech}^2 (t/τ)$ with height $E_0$ and width $τ$, we demonstrate explicitly the interplay between the nonperturbative and perturbative aspects of pair creation in the background field. We analytically compute the number of produced pairs from the vacuum in the Sauter-type field, and the result reproduces Schwinger's nonperturbative formula in the long pulse limit (the constant field limit), while in the short pulse limit it coincides with the leading-order perturbative result. We show that two dimensionless parameters $ν= |eE_0| τ^2$ and $γ= |eE_0| τ/m_e$ characterize the importance of multiple interactions with the fields and the transition from the perturbative to the nonperturbative regime. We also find that pair creation is enhanced compared to Schwinger's formula when the field strength is relativity weak $|eE_0|/m_e^2 \lesssim 1$ and the pulse duration is relatively short $m_e τ\lesssim 1$, and reveal that the enhancement is predominantly described by the lowest order perturbation with a single photon.
description: 12 pages, 8 figures; v2: discussion improved and some figures added; v3: PRD version
Characterizing Wetland Inundation and Vegetation Dynamics in the Arctic Coastal Plain Using Recent Satellite Data and Field Photos
Creators: name: Zou, Zhenhua
name: DeVries, Ben
name: Huang, Chengquan
name: Lang, Megan W.
name: Thielke, Sydney
name: McCarty, Greg W.
name: Robertson, Andrew G.
name: Knopf, Jeff
name: Wells, Aaron F.
name: Macander, Matthew J.
name: Du, Ling
Publisher: name: MDPI
Year: 2021
Subjects: wetland
inundation
vegetation
sentinel
arctic
ANWR
NWI

description: Arctic wetlands play a critical role in the global carbon cycle and are experiencing disproportionate impacts from climate change. Even though Alaska hosts 65% of U.S. wetlands, less than half of the wetlands in Alaska have been mapped by the U.S. Fish and Wildlife Service National Wetlands Inventory (NWI) or other high-resolution wetlands protocols. The availability of time series satellite data and the development of machine learning algorithms have enabled the characterization of Arctic wetland inundation dynamics and vegetation types with limited ground data input. In this study, we built a semi-automatic process to generate sub-pixel water fraction (SWF) maps across the Coastal Plain of the Arctic National Wildlife Refuge (ANWR) in Alaska using random forest regression and 139 Sentinel-2 images taken in ice-free seasons from 2016 to 2019. With this, we characterized the seasonal dynamics of wetland inundation and explored their potential usage in determining NWI water regimes. The highest levels of surface water expression were detected in June, resulting from seasonal active layer thaw and snowmelt. Inundation was most variable in riverbeds, lake and pond margins, and depressional wetlands, where water levels fluctuate substantially between dry and wet seasons. NWI water regimes that indicate frequent inundation, such as permanently flooded wetlands, had high SWF values (SWF ≥ 90%), while those with infrequent inundation, such as temporarily flooded wetlands, had low SWF values (SWF < 10%). Vegetation types were also classified through the synergistic use of a vegetation index, water regimes, synthetic-aperture radar (SAR) data, topographic data, and a random forest classifier. The random forest classification algorithms demonstrated good performance in classifying Arctic wetland vegetation types, with an overall accuracy of 0.87. Compared with NWI data produced in the 1980s, scrub-shrub wetlands appear to have increased from 91 to 258 km2 over the last three decades, which is the largest percentage change (182%) among all vegetation types. However, additional field data are needed to confirm this shift in vegetation type. This study demonstrates the potential of using time series satellite data and machine learning algorithms in characterizing inundation dynamics and vegetation types of Arctic wetlands. This approach could aid in the creation and maintenance of wetland inventories, including the NWI, in Arctic regions and enable an improved understanding of long-term wetland dynamics.
Metrics to Accelerate Private Sector Investment in Sustainable Development Goal 2—Zero Hunger
Creators: name: Brown, Molly E.
Publisher: name: MDPI
Year: 2021
Subjects: sustainable business models
sustainable development
food security
agriculture value chain
earth observation
remote sensing

description: Substantial investment from both the private and public sectors will be needed to achieve the ambitious Sustainable Development Goal 2 (SDG2), which focuses on ending poverty and achieving zero hunger. To harness the private sector, high quality, transparent metrics are needed to ensure that every dollar spent reaches the most marginalized segments of a community while still helping institutions achieve their goals. Satellite-derived Earth observations will be instrumental in accelerating these investments and targeting them to the regions with the greatest need. This article proposes two quantitative metrics that could be used to evaluate the impact of private sector activities on SDG2: measuring increases in yield over baseline and ensuring input availability and affordability in all markets.
Essays in financial credibility of employees opinions
Creators: name: Farhadi, Reza
Publisher: name: No Publisher Supplied
Year: 2018

description: This doctoral dissertation explores the nature of information available to firms’ non-executiveemployees in two chapters. The first chapter examines whether employees, as a group, possessvaluable information about their firms that outside investors and even their managers may nothave? In the first chapter we isolate employee opinions (Glassdoor data) from those of stockmarket participants by focusing on private firms that subsequently go public. Employees’ pre-IPOviews are informative: positive views on firm quality predict stronger post-IPO stock-performance.In addition, dispersion in employee opinions correlates with post-IPO return volatility. Somewhatsurprisingly, employee satisfaction (e.g., work-life-balance) is negatively related to firm performance,after controlling for opinions on firm quality. Negative initial-day stock returns depress employees’views regarding firm quality: hence, leaving ‘money-on-the-table’ helps avoid a loss of employees’morale.In the second chapter we test whether employees continuously provide reliable non-public informationabout their firms? Using textual analysis of Glassdoor data we show that employee opinions,at least in aggregate, are continuously informative about their firms and are positively associatedwith future firm performance and value. Following Quiet life hypothesis, employee-satisfaction (e.g.,work-life-balance & compensation) is negatively related to firm performance, when we control for opinions on firm quality. We also show that employee opinions are more valuable in the presenceof greater complexity and uncertainty. In addition, dispersion in employee opinions correlates withconcurrent and future stock volatility. We also find there is a positive (negative) relation betweenchange in firm size and employees’ view about firm quality (employee satisfaction, controlling forfirm quality). Textual analysis also indicates that employees’ negative and uncertain tone abouttheir firm is negatively related to firm value and predictive of future stock volatility. Finally, we showthat firms’ performance is the main employees’ motivation to provide extended textual disclosureabout their firm.
DoubleML -- An Object-Oriented Implementation of Double Machine Learning in Python
Creators: name: Bach, Philipp
name: Chernozhukov, Victor
name: Kurz, Malte S.
name: Spindler, Martin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: Econometrics (econ.EM)
subject: FOS: Computer and information sciences
subject: FOS: Economics and business
subject: 62-04

description: DoubleML is an open-source Python library implementing the double machine learning framework of Chernozhukov et al. (2018) for a variety of causal models. It contains functionalities for valid statistical inference on causal parameters when the estimation of nuisance parameters is based on machine learning methods. The object-oriented implementation of DoubleML provides a high flexibility in terms of model specifications and makes it easily extendable. The package is distributed under the MIT license and relies on core libraries from the scientific Python ecosystem: scikit-learn, numpy, pandas, scipy, statsmodels and joblib. Source code, documentation and an extensive user guide can be found at https://github.com/DoubleML/doubleml-for-py and https://docs.doubleml.org.
description: 6 pages, 2 figures
Universality and time-scale invariance for the shape of planar Lévy processes
Creators: name: Randon-Furling, Julien
Publisher: name: arXiv
Year: 2014
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Probability (math.PR)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: For a broad class of planar Markov processes, viz. Lévy processes satisfying certain conditions (valid \textit{eg} in the case of Brownian motion and Lévy flights), we establish an exact, universal formula describing the shape of the convex hull of sample paths. We show indeed that the average number of edges joining paths' points separated by a time-lapse $Δτ\in \left[Δτ_1, Δτ_2\right]$ is equal to $2\ln \left(Δτ_2 / Δτ_1 \right)$, regardless of the specific distribution of the process's increments and regardless of its total duration $T$. The formula also exhibits invariance when the time scale is multiplied by any constant. Apart from its theoretical importance, our result provides new insights regarding the shape of two-dimensional objects modelled by stochastic processes' sample paths (\textit{eg} polymer chains): in particular for a total time (or parameter) duration $T$, the average number of edges on the convex hull ("cut off" to discard edges joining points separated by a time-lapse shorter than some $Δτ< T$) will be given by $2 \ln \left(\frac{T}{Δτ}\right)$. Thus it will only grow logarithmically, rather than at some higher pace.
description: 8 pages, 3 figures, accepted in PRE
Many-Joint Robot Arm Control with Recurrent Spiking Neural Networks
Creators: name: Traub, Manuel
name: Legenstein, Robert
name: Otte, Sebastian
Publisher: name: arXiv
Year: 2021
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: In the paper, we show how scalable, low-cost trunk-like robotic arms can be constructed using only basic 3D-printing equipment and simple electronics. The design is based on uniform, stackable joint modules with three degrees of freedom each. Moreover, we present an approach for controlling these robots with recurrent spiking neural networks. At first, a spiking forward model learns motor-pose correlations from movement observations. After training, intentions can be projected back through unrolled spike trains of the forward model essentially routing the intention-driven motor gradients towards the respective joints, which unfolds goal-direction navigation. We demonstrate that spiking neural networks can thus effectively control trunk-like robotic arms with up to 75 articulated degrees of freedom with near millimeter accuracy.
Efficient and mode selective spatial mode multiplexer based on Multi-Plane Light Conversion
Creators: name: Labroille, Guillaume
name: Denolle, Bertrand
name: Jian, Pu
name: Genevaux, Philippe
name: Treps, Nicolas
name: Morizur, Jean-François
Publisher: name: arXiv
Year: 2014
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We designed and built a new type of spatial mode multiplexer, based on Multi-Plane Light Conversion (MPLC), with very low intrinsic loss and high mode selectivity. In this first demonstration we show that a typical 3-mode multiplexer achieves a mode selectivity better than -23 dB and a total insertion efficiency of -4.1 dB (optical coating improvements could increase efficiency to -2.4 dB), across the full C-band. Moreover this multiplexer is able to perform any mode conversion, and we demonstrate its performance for the first 6 eigenmodes of a few-mode fiber: LP$_{01}$, LP$_{11\mathrm{a}}$, LP$_{11\mathrm{b}}$, LP$_{02}$, LP$_{21\mathrm{a}}$ and LP$_{21\mathrm{b}}$.
Spectroscopic interrogation of metal ligation and photoactive properties in metal-organic frameworks
Creators: name: Hanna, Lauren
Publisher: name: No Publisher Supplied
Year: 2020

description: Metal-organic frameworks (MOFs), a class of crystalline hybrid materials, have been studied for a variety of applications ranging from gas sorption to photocatalysis. While the topic of most MOF research focuses on the application of the material, it is important to first understand the structure-function relationship. The adsorption-based functionalities of porous metal-organic framework (MOF) materials that lead to applications such as catalysis and gas separation rely on specific host–guest interactions often involving open metal sites within the nodes of the framework. These interactions are difficult to probe on the molecular level and consequently poorly understood. Spectroscopic methods provide the necessary molecular level information on local metal coordination and electronic structure. In this thesis, steady-state and time resolved optical, x-ray, and vibrational spectroscopic methods are all used to gain molecular level insight, and sometimes a conjunction of techniques are needed to provide a comprehensive answer. Namely, valence-to-core X-ray emission spectroscopy has proven to be exceptionally sensitive to ligand identity, however, for a complete understanding of ligand identity and the nature of the interaction within a given framework, results were complimented with other spectroscopic methods such as Raman spectroscopy and X-ray absorption spectroscopy. Additionally, element specific techniques like X-ray spectroscopic methods, specifically X-ray transient absorption spectroscopy offer element specific excited state information that eludes assignment via convention methods. A brief summary of each chapter is provided below.