cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Studies of high molecular weight systems by NMR spectroscopy
Creators: name: Jabar, Shereen
Publisher: name: The Australian National University
Year: 2018

description: Proteins are essential components for all living cells. For better understanding of proteins and how they work, it is essential to know their 3D structure as well as how they interact with other molecules and their dynamics. Nuclear magnetic resonance (NMR) spectroscopy is a versatile technique to study biomolecules, most notably proteins, in solution. NMR provides structural information at atomic resolution and, compared to the other techniques with similar resolution, the measurements can be carried out under near-physiological conditions that are meaningful for the investigation of dynamics. A great number of unnatural amino acids can now be incorporated into proteins both in vivo and by cell-free protein synthesis at genetically encoded positions. Isotopically labelled unnatural amino acids present outstanding probes for site-specific studies of proteins by NMR. In this thesis, the unnatural amino acid 13C-O-tert-butyltyrosine (13C-Tby) was incorporated as an NMR probe to study the proteins IMP-1 and the E. coli single-stranded DNA binding protein (SSB). IMP-1 is a clinically important metallo-beta-lactamase which catalyzes the hydrolysis of almost all beta-lactam antibiotics. In order to develop inhibitors against this enzyme it is important to understand its structure and dynamics. Pseudocontact shifts (PCSs) provide long-range structural information on biological macromolecules. In Chapter 2, PCSs were measured to study the conformation of an active site loop of IMP-1 and its change upon binding of a ligand. This loop is important as it lines the substrate binding site and contributes to substrate specificity. The results suggest that the binding of an inhibitor induces two different conformations in the loop which are in slow equilibrium between each other. E. coli SSB is a homotetramer of molecular mass 76 kDa. It binds single-stranded DNA (ssDNA) with high affinity and little sequence specificity in two main binding modes, named (SSB)65 and (SSB)35. Chapter 3 describes studies of ssDNA-SSB complexes at high and low salt concentrations by solution NMR spectroscopy. Furthermore, experiments were conducted to determine the binding polarity of ssDNA on SSB. The results obtained are in broad agreement with the unusual binding polarity reported by the crystal structure of a complex between E. coli SSB and a poly-deoxycytidine oligomer. In addition to using the tert-butyl group of a Tby residue as an NMR probe, the present thesis introduced a novel chemical tag containing a trimethylsilyl (TMS) group. Chapter 4 demonstrates the ability of the tert-butyl and TMS groups to deliver site-specific information in high-molecular weight systems without any isotope labelling. The approach was illustrated by measuring intermolecular nuclear Overhauser effects (NOEs) in the 95 kDa complex between SSB and ssDNA.
Fordy-Kulish models and spinor Bose-Einstein condensates
Creators: name: Atanasov, V. A.
name: Gerdjikov, V. S.
name: Grahovski, G. G.
name: Kostov, N. A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: A three-component nonlinear Schrodinger-type model which describes spinor Bose-Einstein condensate (BEC) is considered. This model is integrable by the inverse scattering method and using Zakharov-Shabat dressing method we obtain three types of soliton solutions. The multi-component nonlinear Schrodinger type models related to symmetric spaces C.I Sp(4)/U(2) is studied.
description: 8 pages, LaTeX, jnmp style
Solar Panel Fabrication Techniques for CubeSats
Creators: name: Walker, Tariq
name: Sewell, Scott
name: Rugg, Allyson
name: Weber, Jeff
name: Corchado Albelo, Marcel
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2019

Total Solar Irradiance (TSI) is the measurement of solar energy reaching the earth and is critical for understanding the Earthâs radiation budget. Measuring TSI accurately is best done from space, but space borne platforms are expensive, short lived, and difficult to calibrate. To
alleviate some of these challenges, the High-Altitude Observatory (HAO) proposes development of a CubeSat named the Distributed Irradiance Monitoring Systems (DIMS) that is a fraction of the cost but has the same capabilities. To help lower the potential cost of a DIMS CubeSat, HAO has a project to develop low cost solar panels for DIMS. This begins by researching commercially available options that best fit the needs of DIMS. By weighing cost with efficiency, voltage, and current outputs, SpectroLab XTJ solar cells are ultimately selected.
HAOâs instrumentation team is collaborating with CU student Andrew Dahir to continue development on low cost solar panels. The construction of the solar panel from individual cells using Kapton tape and silver epoxy are described in detail. Once constructed, the solar panel is tested outside and the data collected are analyzed and compared to theoretical efficiency curves. The maximum voltage and current characteristics across two pairs of solar cells is measured by varying resistance. The resulting current-voltage (IV) curves are similar but do not exactly replicate those published by the manufacturer. The discrepancies are likely due to indirect sunlight, the panels being in series, and movement of the sun during the exposure time.
Holographic quantum computing
Creators: name: Tordrup, Karl
name: Negretti, Antonio
name: Molmer, Klaus
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We propose that a single mesoscopic ensemble of trapped polar molecules can support a "holographic quantum computer" with hundreds of qubits encoded in collective excitations with definite spatial phase variations. Each phase pattern is uniquely addressed by optical Raman processes with classical optical fields, while one- and two-qubit gates are accomplished by selectively transferring the individual qubit states to a stripline microwave cavity field and a Cooper pair box where controllable two-level unitary dynamics is governed by classical microwave fields.
description: 4 pages, 3 figures
Investigating CESM1 Ability to Predict Extreme Temperature Events
Creators: name: Wilson, Anthony
name: Medeiros, Brian
name: Caron, Julie
name: Schneider, David
name: Vicente, Vanessa
name: Brea, Pedro
name: Kim, Sung Min
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2019

Climate change is influencing the frequency and intensity of heat waves. In the next century, these extreme events are projected to increase in duration, frequency, and intensity, but these events will not occur uniformly in space and time. This project investigates heat waves using data from observations and the Community Earth System Model, version 1 (CESM1). The observational data set contains daily minimum and maximum temperatures from weather stations that have been combined and gridded using a 0.5° latitude-longitude grid. The CESM1 dataset has been regridded to the same 0.5° grid as the observations. From this data we derived the ninetieth percentile (90pp) of daily maximum and minimum temperatures for each day of the year. This was our threshold to define “extreme temperature” at every location across the globe. Events are then defined as consecutive days that are “extreme” and by identifying such events we compile statistics of duration, frequency, and amplitude. We created case studies such as the Atlanta Heatwave in 1984 and the European Heatwave in 2003 and have shown that the daily maximums in CESM1 agree well with observational data on these events. We have applied the same approach for both the observations and the model and compared them to evaluate the model’s ability to produce realistic heat wave statistics. The model generally produces realistic statistics of where heat waves occur and the amplitude; the main difference between the model and observational data is the duration of the heat wave. Future work will analyze daily minimum temperature, providing a more complete view of extreme temperature events. Both extreme heat and extreme cold events are dangerous for human health, especially if people are not prepared. A better understanding of CESM’s ability to predict extreme temperature events will enable the informed use of model projections in adaptation decision making.
Directed flow of D mesons at RHIC and LHC: non-perturbative dynamics, longitudinal bulk matter asymmetry and electromagnetic fields
Creators: name: Oliva, Lucia
name: Plumari, Salvatore
name: Greco, Vincenzo
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present a study of the directed flow $v_1$ for $D$ mesons discussing both the impact of initial vorticity and electromagnetic field. Recent studies predicted that $v_1$ for $D$ mesons is expected to be surprisingly much larger than that of light charged hadrons; we clarify that this is due to a different mechanism leading to the formation of a directed flow with respect to the one of the bulk matter at both relativistic and non-relativistic energies. We point out that the very large $v_1$ for $D$ mesons can be generated only if there is a longitudinal asymmetry between the bulk matter and the charm quarks and if the latter have a large non-perturbative interaction in the QGP medium. A quite good agreement with the data of STAR and ALICE is obtained if the diffusion coefficient able to correctly predict the $R_{AA}(p_T)$, $v_{2}(p_T)$ and $v_{3}(p_T)$ of $D$ meson is employed. Furthermore, the mechanism for the build-up of the $v_1(y)$ is associated to a quite small formation time that can be expected to be more sensitive to the initial high-temperature dependence of the charm diffusion coefficient. We discuss also the splitting of $v_1$ for $D^0$ and $\bar D^0$ due to the electromagnetic field that is again much larger than the one observed for charged particles and in agreement with the data by STAR that have however still error bars comparable with the splitting itself, while at LHC standard electromagnetic profile assuming a constant conductivity is not able to account for the huge splitting observed.
description: 16 pages, 24 figures
Magnetoelectric generation of a Majorana-Fermi surface in Kitaev's honeycomb model
Creators: name: Chari, Rajas
name: Moessner, Roderich
name: Rau, Jeffrey G.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study the effects of static magnetic and electric fields on Kitaev's honeycomb model. Using the electric polarization operator appropriate for Kitaev materials, we derive the effective Hamiltonian for the emergent Majorana fermions to second-order in both the electric and magnetic fields. We find that while individually each perturbation does not qualitatively alter Kitaev spin liquid, the cross-term induces a finite chemical potential at each Dirac node, giving rise to a Majorana-Fermi surface. We argue this gapless phase is stable and exhibits typical metallic phenomenology, such as linear in temperature heat capacity and finite, but non-quantized, thermal Hall response. Finally, we speculate on the potential for realization of this physics in Kitaev materials.
description: 18 pages, 12 figures
Ranking and Assessment of Seismic Stability of Highway Embankments in Kentucky (KYSPR 96-173)
Creators: name: Sutterer, Kevin G.
name: Harik, Issam E.
name: Allen, David L.
name: Street, Ron
Publisher: name: Kentucky Transportation Center, University of Kentucky
Year: 2000
Subjects: subject: Transportation Engineering

description: This report presents the findings of three independent studies under the same grant. These were (a) assess and rank highway embankments along priority routes in western Kentucky according to seismic stability, (b) assess the seismic stability of the approach embankment for the U.S. 51 Ohio River crossing near Wickliffe, Kentucky, and (c) evaluate the seismic stability of the U.S. 41 Ohio River twin spans north of Henderson, Kentucky. Seismic stability of bridge foundations was not a part of this study.  The highway ranking assessed over 400 embankments and delineated each as having high, moderate, or little risk of significant failure for both the 50 and 500 year events. For the 50 year event, 6 were designated as high risk, while 145 were designated as high risk for the 500 year event. The report recommends evaluation of all high risk embankments and any moderate risk embankments along particularly critical sections of roadway.  The US 51 bridge embankment assessment indicated a high risk of embankment failure for the 500 year event, and a moderate risk of some deformation requiring repair for the 50 year event. The findings suggested the need for an emergency repair plan in the event of either earthquake, and suggested a more detailed evaluation if a higher confidence about the risk of failure was required.  The US 41 bridge embankment evaluation indicated little to no risk of major liquefaction for the 50 and 500 year events. A factor of safety of about 1.0 was estimated for seismic slope stability of the embankment at the bridge abutments, but a detailed stratigraphic section was not possible due to limited project budget. There thus remains some uncertainty about the overall seismic slope stability. The factor of safety is not likely to be significantly less than 1.0. This is acceptable for seismic loading, as a factor of safety of 1.0 implies some deformation of the embankment may occur, but the extent of damage should be repairable on relatively short notice.
Analyzing Weather-regime-dependence of GFS Extended Precipitation Forecast Skill Based on the Convective Adjustment Timescale
Creators: name: Wilson, Malcolm
name: Wong, May
name: Schwartz, Craig
name: Mullally, Dawn
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2019

Numerical weather prediction (NWP) models have been shown to have varying precipitation forecasting skill depending on the dominant weather regime. Specifically, NWP precipitation forecasts are generally more accurate under the equilibrium (synoptic) regime compared to the non-equilibrium (mesoscale) regime, where the former is typically better resolved by current NWP models. Limitations of NWP models, such as model resolution and model error due to physical parameterizations, lead to the discrepancy of forecast skill between the weather regimes. This research evaluated the skill of the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS) extended precipitation forecasts up to 10 days under different weather regimes. The forecast skill was analyzed over the 
 conterminous United States during 2016. Spatial and temporal characteristics of the dominant weather regime were diagnosed based on the convective adjustment timescale. As expected, forecast skill generally degraded with increasing lead time under both regimes. Various skill scores based on a 2 x 2 contingency table indicated that warm-season precipitation forecasts had lower skill relative to the cold season, consistent with results from past studies. The warm season, using the convective adjustment timescale, can be characterized to be dominantly under the non-equilibrium regime, indicating that precipitation forecasting is more difficult under this regime as compared to the equilibrium regime.
Quantum Gravity as a Broken Symmetry Phase of a BF Theory
Creators: name: Mikovic, Aleksandar
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We explain how General Relativity with a cosmological constant arises as a broken symmetry phase of a BF theory. In particular we show how to treat de Sitter and anti-de Sitter cases simultaneously. This is then used to formulate a quantisation of General Relativity through a spin foam perturbation theory. We then briefly discuss how to calculate the effective action in this quantization procedure.
description: This is a contribution to the Proc. of the O'Raifeartaigh Symposium on Non-Perturbative and Symmetry Methods in Field Theory (June 2006, Budapest, Hungary), published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGMA/
title: Intelligent Transportation Systems Strategic Plan
title: (Final Report)
titleType: Subtitle
Creators: name: Walton, Jennifer R.
name: Crabtree, Joseph D.
name: Osborne, Monica L.
name: Pigman, Jerry G.
name: Weber, J.M.
name: Grossardt, Ted H.
name: Hartman, Donald G.
Publisher: name: Kentucky Transportation Center, University of Kentucky
Year: 2000
Subjects: subject: Transportation Engineering

description: This report presents a Strategic Plan for Intelligent Transportation Systems (ITS) in Kentucky. The purpose of this Strategic Plan is to offer a vision for ITS in Kentucky and to identify key goals for each functional area of ITS. Some of the fundamental elements of achieving the ITS vision are presented and discussed, including public relations and marketing, operations and maintenance, and organizational structure.  This plan serves as the foundation for development of a Statewide ITS Architecture and an ITS Business Plan, both of which are currently in progress.
Developing Instrumentation for Measuring Solar Magnetic Fields: Investigations into Space Qualified Microcontrollers
Creators: name: Walker, Tariq
name: Sewell, Scott
name: Vรถmel, Holger
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2020

Life on earth is enabled by the warmth and light we receive from the sun. Not all the effects of the sun, however, are beneficial to life. Solar magnetic fields can produce large explosive events in the solar atmosphere, which bombard the earth with harmful levels of particles and radiation. Solar physicists hope to be able to predict these harmful solar events. This would allow humans to avoid the most harmful effects including damage to satellites, the earth's power grid, and to astronauts. The High Altitude Observatory (HAO) at National Center for Atmospheric Research has proposed a spaceborne CubeSat to measure magnetic fields using diagnostic emission lines. This paper presents an investigation into the use of a space-qualified microcontroller (TI MSP430FR5969), which will work as a science payload controller for this application. The work presents an interrupt-based software architecture which will be extensible to performing all of the required control and communication requirements between the payload and the spacecraft.
Hot ion generation from nanostructured surfaces under intense, femtosecond irradiation
Creators: name: Bagchi, S.
name: Kiran, P. Prem
name: Bhuyan, M. K.
name: Bose, S.
name: Ayyub, P.
name: Krishnamurthy, M.
name: Kumar, G. Ravindra
Publisher: name: arXiv
Year: 2006
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We present the effect of a nanostructured surface on the emission of ions and electrons from intense (5-36 Petwatt per sq.cm) femtosecond laser produced plasmas. Electrons from optically polished copper targets coated with copper nanoparticles (CuNP) are observed to be hotter than those from uncoated polished targets. A nearly two-fold enhancement is observed for ions in the range 14-74 keV, while ion yield decreases by a factor of 2 in the 74-2000 keV range. The total ion yields measured using a large area Faraday cup are more from CuNP targets than those from polished Cu targets, indicating increased ion beam divergence due to surface modulations.
description: 14 pages, 4 figures
Electronic correlations and magnetic interactions in infinite-layer NdNiO$_2$
Creators: name: Katukuri, Vamshi M.
name: Bogdanov, Nikolay A.
name: Weser, Oskar
name: Brink, Jeroen van den
name: Alavi, Ali
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: The large antiferromagnetic exchange coupling in the parent high-$T_{\rm c}$ cuprate superconductors is believed to play a crucial role in pairing the superconducting carriers. The recent observation of superconductivity in hole-doped infinite-layer (IL-) NdNiO$_2$ brings to the fore the relevance of magnetic coupling in high-$T_{\rm c}$ superconductors, particularly because no magnetic ordering is observed in the undoped IL-NdNiO$_2$ unlike in parent copper oxides. Here, we investigate the electronic structure and the nature of magnetic exchange in IL-NdNiO$_2$ using state-of-the-art many-body quantum chemistry methods. From a systematic comparison of the electronic and magnetic properties with isostructural cuprate IL-CaCuO$_2$, we find that the on-site dynamical correlations are significantly stronger in IL-NdNiO$_2$ compared to the cuprate analog. These dynamical correlations play a critical role in the magnetic exchange resulting in an unexpectedly large antiferromagnetic nearest neighbor isotropic $J$ of 77 meV between the Ni$^{1+}$ ions within the $ab$-plane. While we find many similarities in the electronic structure between the nickelate and the cuprate, the role of electronic correlations is profoundly different in the two. We further discuss the implications of our findings in understanding the origin of superconductivity in nickelates.
description: 7 pages including references. For Supplemental Material, please see the publisher website
Regularizing (away) vacuum energy
Creators: name: Koberinski, Adam
Publisher: name: arXiv
Year: 2021
Subjects: subject: History and Philosophy of Physics (physics.hist-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this paper I formulate Minimal Requirements for Candidate Predictions in quantum field theories, inspired by viewing the standard model as an effective field theory. I then survey standard effective field theory regularization procedures, to see if the vacuum expectation value of energy density ($\langleρ\rangle$) is a quantity that meets these requirements. The verdict is negative, leading to the conclusion that $\langleρ\rangle$ is not a physically significant quantity in the standard model. Rigorous extensions of flat space quantum field theory eliminate $\langleρ\rangle$ from their conceptual framework, indicating that it lacks physical significance in the framework of quantum field theory more broadly. This result has consequences for problems in cosmology and quantum gravity, as it suggests that the correct solution to the cosmological constant problem involves a revision of the vacuum concept within quantum field theory.
description: Forthcoming in Foundations of Physics
Simulating Generating Cells and their Environment during the SNOWIE Campaign
Creators: name: Gordillo, Nicolas
name: Xue, Lulin
name: Chen, Sisi
name: Jensen, Anders
name: Wolff, Jamie
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2020

Mountain precipitation is an important product of orographic flow. It is crucial for farmers whose livelihood depends on the water and for hydroelectric uses in mountainous regions. Thus, the Seeded and Natural Orographic Wintertime Clouds: The Idaho Experiment (SNOWIE) campaign was conducted to understand orographic precipitation and associated microphysical processes such as cloud top generating cells. Cloud top generating cells are small convective elements on the top of the orographic clouds. They exert a large impact on the temporal and spatial distribution of orographic precipitation by producing locally enhanced ice or drizzle. This research aimed to examine whether generating cells observed in the SNOWIE campaign could be simulated using the Weather Research and Forecasting (WRF) model. The simulation was run using three nested domains with a horizontal resolution of 900, 300, and 100 m. The environment was initialized in the 900 m run using two European Center for Medium-Range Weather Forecasts reanalysis datasets (ERA), ERA5 and ERAInterim. To resolve the small-scale generating cells, 300 and 100 m WRF Large Eddy Simulations (LES) were also run. Signals in microphysical and dynamical fields such as cloud mixing ratio, precipitation amount, and vertical motion were analyzed to identify features associated with generating cells. Examining the pattern of these signals in the 100 m run qualitatively indicated cloud-top generating cells. Future work includes modifying the initial and boundary conditions and microphysical backgrounds for the 300 and 100 m resolution domains to test the sensitivity of the cloud top generating cells to environments and aerosols.
On the determination of curvature and dynamical Dark Energy
Creators: name: Virey, J. -M.
name: Talon-Esmieu, D.
name: Ealet, A.
name: Taxil, P.
name: Tilquin, A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Constraining simultaneously the Dark Energy(DE) equation of state and the curvature of the Universe is difficult due to strong degeneracies. To circumvent this problem when analyzing data it is usual to assume flatness to constrain DE, or conversely, to assume that DE is a cosmological constant to constrain curvature. In this paper, we quantify the impact of such assumptions in view of future large surveys. We simulate future data for type Ia Supernovae (SNIa), Cosmic Microwave Background (CMB) and Baryon Acoustic Oscillations (BAO) for a large range of fiducial cosmologies allowing a small spatial curvature. We take into account a possible time evolution of DE through a parameterized equation of state : $w(a) = w_0 + (1-a) w_a$. We then fit the simulated data with a wrong assumption on the curvature or on the DE parameters. For a fiducial $Λ$CDM cosmology, if flatness is incorrectly assumed in the fit and if the true curvature is within the ranges $0.01
description: 17 pages, 5 eps figures, final version to be published in JCAP. Several modifications for text and figures but conclusions are unchanged
Comparative Analysis of Supercell Environment in Hurricanes Harvey and Irma
Creators: name: MacDaniel, Ivy
name: Rozoff, Christopher
name: Carroll-Smith, Dereka
name: Vigh, Jonathan
name: Davis, Chris
name: Aponte, Kristen
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2020

Although severe weather forecasting has improved over time, small rotating thunderstorms, sometimes called miniature supercells, often pose challenges with tracking and issuing tornado warnings. Being smaller than typical supercells, those storms are more difficult to discern on radar, especially at greater distances. Those storms are also found in tornado-producing tropical cyclones, and tornadoes produced by tropical cyclones, while they tend to be weak, can still pose a threat to lives and properties in the Southeast U.S. The most likely tropical cyclone to produce tornadoes is a formerly intense tropical cyclone that weakens at landfall. Tornadoes within Hurricanes Harvey and Irma from the 2017 Atlantic season were examined in this study. In Harveyâs case, the majority of tornadoes formed inland from southeast Texas to Tennessee. Mesoanalysis showed moderately high convective available potential energy (CAPE) and more moderate vertical wind shear than was found in Irma. Irma, however, produced the majority of tornadoes near the shoreline. Environmental analysis showed higher CAPE over water than over the Florida peninsula during Irma's landfall. Yet, the shear was higher over land. However, supercells met their demise over the land when the environment became unfavorable. While it was still unclear why the supercells died over land, a key observation showed that there was a significant decrease of CAPE over land compared to offshore despite favorable shear. However, supercells in post-tropical Harvey formed and sustained themselves far inland while being driven by buoyancy. Thus, additional investigation in the future would be necessary.
Detecting Dark Photons from Atomic Rearrangement in the Galaxy
Creators: name: Eiger, James
name: Geller, Michael
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study a new dark sector signature for an atomic process of "rearrangement" in the galaxy. In this process, a hydrogen-like atomic dark matter state together with its anti-particle can rearrange to form a highly-excited bound state. This bound state will then de-excite into the ground state emitting a large number of dark photons that can be measured in experiments on Earth through their kinetic mixing with the photon. We find that for DM masses in the GeV range, the dark photons have enough energy to pass the thresholds of neutrino observatories such as Borexino and Super-Kamiokande that can probe for our scenario even when our atomic states constitute a small fraction of the total DM abundance. We study the corresponding bounds on the parameters of our model from current data as well as the prospects for future detectors.
description: 10 pages, 2 figures
A note on the invariance principle of the product of sums of random variables
Creators: name: Zhang, Li-Xin
name: Huang, Wei
Publisher: name: arXiv
Year: 2006
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60F15;60G50

description: In literature, the central limit theorems for the product of sums of various random variables have studied. The purpose of this note is to show that this kind of results are corollary of the invariance principle.
Using Bayes' Theorem to Understand Uncertainty in the North American Mesoscale (NAM) Model: A Spatial Analysis of Rainfall Forecast Error for Hurricane Barry
Creators: name: Smith, Ebone
name: Siems-Anderson, Amanda
name: Zick, Stephanie
name: Moulton, Melissa
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2020

Tropical cyclones present grave risks to coastal communities. Strong winds, storm surge, flooding, and heavy rainfall result in billions of dollars of damage to homes, infrastructure, and agricultural resources, as well as injuries and fatalities. Meteorologists use forecast models to predict the hazardous impacts of hurricanes such that these hazards can be communicated to vulnerable communities. Under some unknown conditions, there are large errors in tropical cyclonesâ forecasted rainfall; because of this, it is difficult to predict rainfall impacts from landfalling hurricanes. To build more resilience in these communities, it is imperative that scientists gain insight into model uncertainty patterns, determine causes of model errors, and use those uncertainties to improve warnings to the public. This study investigates forecast model uncertainty by comparing the North American Mesoscale (NAM) model forecasted rainfall with the observed rainfall from Hurricane Barry (2018). In addition, NAM model forecast errors from 47 tropical storms are used as inputs to a Bayesian model to evaluate how the forecasted precipitation error varies spatially in 1000 hypothetical rainfall scenarios. The analysis, of the rainfall forecast error from these scenarios, consisted of three methods: 1) an analysis of the probability density function of error magnitudes forecasted by the Bayesian model, 2) a spatial, comparative analysis of mapped rainfall from the NAM model, Stage IV observations, and Bayesian model scenarios, and 3) a comparison of descriptive statistics for different vulnerable communities with boxplots. The results demonstrated that the modeled error values mostly fell within a small range; however, many simulations had outlier error values that stretched past the extreme values. Forecasted precipitation scenarios calculated from the modeled error values and the observed rainfall revealed a large range of potential rainfall amounts, as well as spatial variability of the rainfall distribution.
Heavy Flavour Baryons in Hyper Central Model
Creators: name: Patel, Bhavin
name: Rai, Ajay Kumar
name: Vinodkumar, P. C.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Heavy flavor baryons containing single and double charm (beauty) quarks with light flavor combinations are studied using the hyper central description of the three-body problem. The confinement potential is assumed as hyper central coulomb plus power potential with power index $\upsilon$. The ground state masses of the heavy flavor, $J^P={1/2}^+$ and ${3/2}^+$ baryons are computed for different power index, $ ν$ starting from 0.5 to 2.0. The predicted masses are found to attain a saturated value in each case of quark combinations beyond the power index $ν=1.0$.
description: 10 pages, 4 figures
People, Perceptions, and Plights: Survey Respondents' Perspectives on Tornado Sheltering during the COVID-19 Pandemic
Creators: name: Williams, Christopher L.
name: Ash, Kevin
name: Demuth, Julie
name: Kucera, Paul
name: Morss, Rebecca
name: Wilhelmi, Olga
name: Ahijevych, David
name: Garcia, Brandon
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2020

This study investigated how tornado sheltering needs and the novel coronavirus disease (COVID-19) pandemic intersect in relation to human risk perception and intended behavior for tornado threats. Housing types like mobile homes are less likely to maintain structural integrity when facing tornadic winds and flying debris than housing types such as single-family homes. When tornadoes threaten, trusted authorities encourage people living in less sturdy homes to seek shelter at designated public facilities or at sturdier homes of friends and family. As tornado season neared peak climatological frequency of occurrence across southern regions of the Central and Eastern United States in 2020, the World Health Organization declared COVID-19 a pandemic. Medical authorities pleaded for entities to help reduce disease transmission by limiting gathering in large crowds, establishing quarantines, and isolating those infected with COVID-19. If individually recommended protective behaviors for tornadoes and COVID-19 were implemented simultaneously, then conflict potential arises. This study conducted statistical analyses on data from a recent Qualtrics survey conducted online with members of the public in twenty U.S. states to explore where recommended responses to the concurrent tornado and COVID-19 hazard intersect and create a potential paradox. An example key finding is how respondents perceive comprehensive risk reduction communication coming from official public channels as lacking clarity. Given the recency of the tornado and COVID-19 risk intersection, the analysis findings may offer relevant insight to trusted authorities in the weather forecast and warning system as they adapt in areas like risk communication and emergency shelter operations.
Investigating Frontal Precipitation Enhancement Upstream of the Olympic Mountains
Creators: name: Garcia, Brandon Antonio
name: Eidhammer, Trude
name: Hence, Deanna A.
name: Rauber, Robert M.
name: Tessendorf, Sarah A.
name: Williams, Christopher
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2020

Orographic precipitation enhancement is the tendency of mountains to cause clouds to produce more precipitation than they would otherwise, which greatly affects the total rainfall in mountainous regions and plays a major role in flooding and mudslides. Most past studies have examined this enhancement close to the mountains themselves. The present study examined the orographic enhancement of frontal precipitation upstream of the Olympic Mountains of Washington State, using data from a Weather Research and Forecasting (WRF) regional climate simulation. Using this simulation, we strived to determine how thermodynamic and dynamic conditions affect the enhancement of frontal precipitation upstream of the Olympic Mountains. To do so, the characteristics of frontal passages were analyzed, including frontal type, orientation, velocity, warm-air moisture content, and accumulated precipitation. Of the five fronts analyzed to date, there were two cold fronts, two warm fronts, and one occluded front. We then analyzed each characteristic by comparing each event to each other and as a function of distance from the mountains. We found that all fronts slowed down as they approached the mountains, four of which to almost half of their original speeds, and some even beginning to decelerate upwards of 700 km upstream. Areas of enhanced precipitation were observed along the two cold fronts, as far upstream as 560 km. These results document upstream impacts on frontal passages, but further analysis is needed to examine additional frontal passages and determine if the observed precipitation enhancement and frontal deceleration were caused by orographic effects from the Olympic Mountains.
Characterization of 32b1, a partial cDNA encoding novel sequence having high similarity with the immediate early gene, Cyr61
Creators: name: Chow, Cynthia Hsueh-Ying
Publisher: name: University of British Columbia
Year: 2009

description: The 32b1 cDNA clone was isolated from a λgtll library made from a Jurkat T lymphocyte cell line during a search for a transactivating factor for the HIV-LTR that was responsible for Ras responsiveness. The clone was 1.3kb in length and the fulllength clone, postulated from Northern blot experiments done in human tissues, was estimated to be approximately 2.6 kb. This led to a comprehensive search of different libraries of human blood leukocytes, lung and brain cell lines to find the missing 5'end. Although the original segment of cDNA clone was isolated many times, novel sequence was never found experimentally. A search in the NCBI database revealed new 5' end sequence as well as evidence linking 32b1 with wound repair. Further examination of the gene induction kinetics were carried out via Northern Hybridizaiton analysis. Unexpectedly, the gene was not found in peripheral blood leukocytes and none of the cell lines that the cDNA clone was isolated from was seen to express it. The only cell line that did express it was a Rat-2 fibroblast cell line where a message having high sequence similarity with 32b1 was seen to be induced by serum, EGF but not by the phorbol ester, PMA. The stability of the rat mRNA transcript was also studied from induction patterns after actinomycin D treatment with and without cycloheximide. It was found to have an transient half life of less than 30 minutes. The induction of the 32b1 mRNA message was prolonged after treatment with cycloheximide which implicated that translation had an effect on its mRNA stability. These results allowed certain conclusions to be made about 32b1 that can be a basis in further research into its function in cell proliferation. The focus of this research was to complete the cDNA sequence, find the missing 5' end of the cloned cDNA and to characterize the expression of the gene.
Turbulent transport and its effect on the dead zone in protoplanetary discs
Creators: name: Ilgner, Martin
name: Nelson, Richard P.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Protostellar accretion discs have cool, dense midplanes where externally originating ionisation sources such as X-rays or cosmic rays are unable to penetrate. This suggests that for a wide range of radii, MHD turbulence can only be sustained in the surface layers where the ionisation fraction is sufficiently high. A dead zone is expected to exist near the midplane, such that active accretion only occurs near the upper and lower disc surfaces. Recent work, however, suggests that under suitable conditions the dead zone may be enlivened by turbulent transport of ions from the surface layers into the dense interior. In this paper we present a suite of simulations that examine where, and under which conditions, a dead zone can be enlivened by turbulent mixing. We use three-dimensional, multifluid shearing box MHD simulations, which include vertical stratification, ionisation chemistry, ohmic resistivity, and ionisation due to X-rays from the central protostar. We compare the results of the MHD simulations with a simple reaction-diffusion model. The simulations show that in the absence of gas-phase heavy metals, such as magnesium, turbulent mixing has essentially no effect on the dead zone. The addition of a relatively low abundance of magnesium, however, increases the recombination time and allows turbulent mixing of ions to enliven the dead zone completely beyond a distance of 5 AU from the central star, for our particular disc model. During the late stages of protoplanetary disc evolution, when small grains have been depleted and the disc surface density has decreased below its high initial value, the structure of the dead zone may be significantly altered by the action of turbulent transport.
description: 20 pages, 11 figures, accepted for publication in A&A, high resolution pdf available at http://www.maths.qmul.ac.uk/~rpn/preprints/index.html
Transcription of a story about abandoned kids who turned into flowers
Creators: name: Parker, Verdena
name: Spence, Justin
name: Rice, Keren
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2022
Subjects: subject: hup

description: Audio file VP-111010-01: transcription of a story about abandoned kids who turned into flowers (file VP-150309-03), from 9:12 to the end of the story
Exploring the robustness of Keplerian signals to the removal of active and telluric features
Creators: name: Lisogorskyi, Maksym
name: Jones, Hugh R. A.
name: Feng, Fabo
name: Butler, R. Paul
name: Vogt, Steven S.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We examine the influence of activity- and telluric-induced radial velocity signals on high resolution spectra taken with an iodine absorption cell. We exclude 2 Angstrom spectral chunks containing active and telluric lines based on the well characterised K1V star Alpha Centauri B and illustrate the method on Epsilon Eridani - an active K2V star with a long period low amplitude planetary signal. After removal of the activity- and telluric-sensitive parts of the spectrum from the radial velocity calculation, the significance of the planetary signal is increased and the stellar rotation signal disappears. In order to assess the robustness of the procedure, we perform Monte Carlo simulations based on removing random chunks of the spectrum. Simulations confirm that the removal of lines impacted by activity and tellurics provides a method for checking the robustness of a given Keplerian signal. We also test the approach on HD 40979 which is an active F8V star with a large amplitude planetary signal. Our Monte Carlo simulations reveal that the significance of the Keplerian signal in the F star is much more sensitive to wavelength. Unlike the K star the removal of active lines from the F star greatly reduces the radial velocity precision. In this case, our removal of a K star active lines from an F star does not a provide a simple useful diagnostic because it has far less radial velocity information and heavily relies on the strong active lines.
description: 12 pages, 6 figures. Accepted for publication in MNRAS
Σύμβαση forfaiting -πώληση επιχειρηματικής απαίτησης
Creators: name: Παπαδοπούλου, Ελένη Ταξιάρχη
Publisher: name: Aristotle University of Thessaloniki
Year: 2008
Subjects: Πρακτορεία επιχειρηματικής απαίτησης
Πράκτορας
Προμηθευτής-εξαγωγέας
Πώληση δικαιώματος (επιχειρηματική απαίτηση)
Αξιόγραφα
Ασφαλιζόμενη απαίτηση
Forfaiting of forfeiting
Forfaiter or forfeiter
Forfaitisi or forfeitisi
Ecomissary note
Bill of exchange
Bank guarantee

description: Η σύμβαση πρακτορείας επιχειρηματικής απαίτησης αφορά στην πώληση μιας μεμονωμένης εξαγωγικής επιχειρηματικής απαίτησης, ενσωματωμένη σε αξιόγραφα, από τον προμηθευτή στον πράκτορα, χωρίς δικαίωμα αναγωγής του τελευταίου εναντίον του προμηθευτή πελάτη του, εάν ο πράκτορας δεν ικανοποιηθεί τελικά από τον πρωτοφειλέτη
description: Forfaiting is the purchase of a debt expressed in a negotiable instrument, such as a bill of exchange or a promissory note from the creditor on a non-resource bases, i.e. the purchaser known as the forfaiter, undertakes the waive-to forfeit-his right of recourse against the creditor if he cannot obtain satisfaction from the debtor
X-Ray Emission from Planetary Nebulae Calculated by 1D Spherical Numerical Simulations
Creators: name: Akashi, Muhammad
name: Soker, Noam
name: Behar, Ehud
name: Blondin, John
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We calculate the X-ray emission from both constant and time evolving shocked fast winds blown by the central stars of planetary nebulae (PNs) and compare with observations. Using spherically symmetric numerical simulations with radiative cooling, we calculate the flow structure, and the X-ray temperature and luminosity of the hot bubble formed by the shocked fast wind. We find that a constant fast wind gives results that are very close to those obtained from the self-similar solution. We show that in order for a fast shocked wind to explain the observed X-ray properties of PNs, rapid evolution of the wind is essential. More specifically, the mass loss rate of the fast wind should be high early on when the speed is ~300-700 km/s, and then it needs to drop drastically by the time the PN age reaches ~1000 yr. This implies that the central star has a very short pre-PN (post-AGB) phase.
description: accepted to MNRAS
Analyzing Heat Wave Statistics in the Community Earth System Model: Sensitivity to Resolution
Creators: name: Wilson, Anthony
name: Medeiros, Brian
name: Caron, Julie
name: Mullaly, Dawn
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2020

Climate change is influencing the frequency and intensity of heat waves. In the next century, these extreme events are projected to increase in duration, frequency, and intensity. However, these events will not occur uniformly in space and time. This project's early stages focused on looking at heat waves using data from observations and the 1° resolution version of the Community Earth System Model, version 1 (CESM1). The observational data set contains daily minimum and maximum temperatures from weather stations that have been combined and gridded using a 0.5° latitude-longitude grid. The CESM1 dataset has been regridded to the same 0.5° grid as the observations. In this study we also include the higher resolution CESM1 0.25° to analyze the impact of increased resolution on the fidelity of heat events. From these data we derived the ninetieth percentile (90pp) of daily maximum and minimum temperatures for each day of the year. This was our threshold to define extreme temperature at every location across the globe. Events are then defined as consecutive days that are extreme. By identifying such events we are able to determine their statistics, such as number, duration and intensity, globally and seasonally where these events occur. CESM 1° resolution has many more long-duration events than CESM 0.25 resolution. This appears to be an example of where CESM 0.25° resolution is closer to observations than CESM 1° resolution. CESM 1°resolution has events that tend to be much longer than expected. Both models appear to capture the observed feature that heat wave night events aren't as persistent as heat wave day events. Future work will provide possible sources of predictability for heat waves. Heat waves pose a dangerous threat to human health, especially if people are not prepared. A better understanding of CESM’s ability to predict heat waves will enable the use of model projections in adaptation decision making.