cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Enhanced hysteresis in the semiconductor-to-metal phase transition of VO2 precipitates formed in SiO2 by ion implantation
Creators: name: Feldman, L.C.
name: Lopez, R.
name: Boatner, L.A.
name: Haynes, T.E.
name: Haglund, R.F.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2001

description: A strongly enhanced hysteresis with a width of >34°C has been observed in the semiconductor-to-metal phase transition of submicron-scale VO2 precipitates formed in the near-surface region of amorphous SiO2 by the stoichiometric coimplantation of vanadium and oxygen and subsequent thermal processing. This width is approximately an order of magnitude larger than that reported previously for the phase transition of VO2 particles formed in Al2O3 by a similar technique. The phase transition is accompanied by a significant change in infrared transmission. The anomalously wide hysteresis loop observed here for the VO2/SiO2 system can be exploited in optical data storage and switching applications in the infrared region.
Nanoformulated Remdesivir with Extremely Low Content of Poly(2-oxazoline)-Based Stabilizer for Aerosol Treatment of COVID-19
Creators: name: Ramsey, Jacob D.
name: Hwang, Duhyeong
name: Madden, Emily A.
name: Stewart, Ian E.
name: Hickey, Anthony J.
name: Kabanov, Alexander V.
name: Lim, Chaemin
name: Heise, Mark T.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2022

description: The rise of the novel virus SARS-CoV2 which causes the disease known as COVID-19 has led to a global pandemic claiming millions of lives. With no clinically approved treatment for COVID-19, physicians initially struggled to treat the disease, and a need remains for improved antiviral therapies in this area. It is conceived early in the pandemic that an inhalable formulation of the drug remdesivir which directly targets the virus at the site of infection could improve therapeutic outcomes in COVID-19. A set of requirements are developed that would be conducive to rapid drug approval: 1) try to use GRAS reagents 2) minimize excipient concentration and 3) achieve a working concentration of 5 mg/mL remdesivir to obtain a deliverable dose which is 5-10% of the IV dose. In this work, it is discovered that Poly(2-oxazoline) block copolymers can stabilize drug nanocrystal suspensions and provide suitable formulation characteristics for aerosol delivery while maintaining antiviral efficacy. The authors believe POx block copolymers can be used as a semi-ubiquitous stabilizer for the rapid development of nanocrystal formulations for new and existing diseases.
DNA twist stability changes with magnesium(2+) concentration
Creators: name: Broekmans, Onno D.
name: King, Graeme A.
name: Stephens, Greg J.
name: Wuite, Gijs J. L.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: For an understanding of DNA elasticity at high mechanical loads (F > 30 pN), its helical nature needs to be taken into account, in the form of coupling between the twist and stretch degrees of freedom. The prevailing model for DNA elasticity, the worm-like chain, was previously extended to include this twist-stretch coupling, giving rise to the twistable worm-like chain. Motivated by DNA's charged nature, and the known effects of ionic charges on the molecule's persistence length and stretch modulus, we explored the impact of buffer ionic conditions on twist-stretch coupling. After developing a robust fitting approach for force-extension data, we find that DNA's helical twist is stabilized at high concentrations of the magnesium divalent cation.
description: 4 pages, 5 figures
Improbabilism
Creators: name: Graham, Hayden
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2022

description: The free will debate is usually about its compatibility with determinism, or how it relates to moral responsibility. In this paper, I take a different approach, one focused on the metaphysical possibility of free will in our world. I first make clear which facet of free will is being discussed, then move on to my positive argument that it is improbable we live in one of the possible worlds where free will exists. I do so by providing two necessary conditions for free will: the ability to do otherwise and the ability to sufficiently determine our actions. These necessary conditions lie on opposite sides of the probability spectrum such that it renders them improbably compossible. The ability to do otherwise lies closer to the .5 point on the scale, whereas sufficient determining actions lies much closer to 1. Our understanding of our world leads us to grant sufficient determinism according to our nomological laws. This doesn’t push the possibility of free will out of the window. Instead, it allows for the possibility of it in our world, but only in an improbable fashion.
Measuring the Numerical Viscosity in Simulations of Protoplanetary Disks in Cartesian Grids -- The Viscously Spreading Ring Revisited
Creators: name: Joseph, Jibin
name: Ziampras, Alexandros
name: Jordan, Lucas
name: Turpin, George A.
name: Nelson, Richard P.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Hydrodynamical simulations solve the governing equations on a discrete grid of space and time. This discretization causes numerical diffusion similar to a physical viscous diffusion, whose magnitude is often unknown or poorly constrained. With the current trend of simulating accretion disks with no or very low prescribed physical viscosity, it becomes essential to understand and quantify this inherent numerical diffusion, in the form of a numerical viscosity. We study the behavior of the viscous spreading ring and the spiral instability that develops in it. We then use this setup to quantify the numerical viscosity in Cartesian grids and study its properties. We simulate the viscous spreading ring and the related instability on a two-dimensional polar grid using PLUTO as well as FARGO, and ensure convergence of our results with a resolution study. We then repeat our models on a Cartesian grid and measure the numerical viscosity by comparing results to the known analytical solution, using PLUTO and Athena++. We find that the numerical viscosity in a Cartesian grid scales with resolution as approximately $ν_{num}\proptoΔx^2$ and is equivalent to an effective $α\sim10^{-4}$ for a common numerical setup. We also show that the spiral instability manifests as a single leading spiral throughout the whole domain on polar grids. This is contrary to previous results and indicates that sufficient resolution is necessary in order to correctly resolve the instability. Our results are relevant in the context of models where the origin should be included in the computational domain, or when polar grids cannot be used. Examples of such cases include models of disk accretion onto a central binary and inherently Cartesian codes.
Safety criteria for flying E-sail through solar eclipse
Creators: name: Janhunen, Pekka
name: Toivanen, Petri
Publisher: name: arXiv
Year: 2015
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The electric solar wind sail (E-sail) propellantless propulsion device uses long, charged metallic tethers to tap momentum from the solar wind to produce spacecraft propulsion. If flying through planetary or moon eclipse, the long E-sail tethers can undergo significant thermal contraction and expansion. Rapid shortening of the tether increases its tension due to inertia of the tether and a Remote Unit that is located on the tether tip (a Remote Unit is part of typical E-sail designs). We analyse by numerical simulation the conditions under which eclipse induced stresses are safe for E-sail tethers. We calculate the closest safe approach distances for Earth, Moon, Venus, Mars, Jupiter, Ceres and an exemplary 300 km main belt asteroid Interamnia for circular, parabolic and hyperbolic orbits. We find that any kind of eclipsing is safe beyond approximately 2.5 au distance, but for terrestrial planets safety depends on the parameters of the orbit. For example, for Mars the safe distance with 20 km E-sail tether lies between Phobos and Deimos orbits.
description: 12 pages, 4 figures, 2 tables, accepted in Acta Astronautica
Oort Cloud Comets Discovered Far from the Sun
Creators: name: Królikowska, Małgorzata
name: Dones, Luke
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Context: Increasingly, Oort Cloud comets are being discovered at great distances from the Sun and tracked over ever wider ranges of heliocentric distances as observational equipment improves. Aims: To investigate in detail how the original semimajor axis for near-parabolic comets depends on the selected data arc and the assumed form of the non-gravitational (NG) acceleration. Methods: Among currently known Oort Cloud comets with large perihelion distances ($q > 3$ au), we selected 32 objects observed over the widest ranges of heliocentric distances in orbital legs before and after perihelion. For each of them, we determined a series of orbits using at least three basic types of data sets selected from available positional data (pre- and post-perihelion data and the entire data set), and a few forms of NG acceleration representing water ice or CO sublimation. Results: We found that the motion of comets is often measurably affected by NG forces at heliocentric distances beyond 5 au from the Sun. The most spectacular example is C/2010 U3 (Boattini), whose perihelion distance is 8.44 au. NG effects are detectable for 19 of the 32 comets within the positional data. For five comets, we found asymmetric effects of NG forces - in three cases significantly greater before perihelion than afterward (C/2017 M4, C/2000 SV$_{75}$, and C/2015 O1), and in two others the opposite (C/1997 BA$_6$ and C/2006 S3). We also find that the well-known systematic effect of finding more tightly bound original orbits when including the NG acceleration than in purely gravitational solutions may be related to the specific form of the standard $g(r)$ function describing the sublimation of ices.
description: 22 pages, 11 tables, 10 figures. Astronomy & Astrophysics, in press
Disordered surface vibrations in jammed sphere packings
Creators: name: Sussman, Daniel M.
name: Goodrich, Carl P.
name: Liu, Andrea J.
name: Nagel, Sidney R.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study the vibrational properties near a free surface of disordered spring networks derived from jammed sphere packings. In bulk systems, without surfaces, it is well understood that such systems have a plateau in the density of vibrational modes extending down to a frequency scale $ω^*$. This frequency is controlled by $ΔZ = \langle Z \rangle - 2d$, the difference between the average coordination of the spheres and twice the spatial dimension, $d$, of the system, which vanishes at the jamming transition. In the presence of a free surface we find that there is a density of disordered vibrational modes associated with the surface that extends far below $ω^*$. The total number of these low-frequency surface modes is controlled by $ΔZ$, and the profile of their decay into the bulk has two characteristic length scales, which diverge as $ΔZ^{-1/2}$ and $ΔZ^{-1}$ as the jamming transition is approached.
description: 7 pages, 5 figures
On gluon and ghost propagators in linear covariant gauges
Creators: name: Huber, Markus Q.
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We compute the gluon and ghost propagators of Yang-Mills theory in linear covariant gauges from the coupled system of Dyson-Schwinger equations. For small values of the gauge fixing parameter $ξ\sim 0.1$, the deviations to the Landau gauge already become clearly visible. For the ghost dressing function, this is reflected in a logarithmic infrared suppression. Also, the gluon dressing function changes - but only quantitatively - and the gluon propagator remains finite at zero momentum. From the results, a running coupling is extracted.
description: 9 pages, 3 figures, agrees with version published in PRD
Stochastic energetics of a colloidal particle trapped in a viscoelastic bath
Creators: name: Darabi, Farshad
name: Ferrer, Brandon R.
name: Gomez-Solano, Juan Ruben
Publisher: name: arXiv
Year: 2023
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We investigate the statistics of the fluctuations of the energy transfer between an overdamped Brownian particle, whose motion is confined by a stationary harmonic potential, and a surrounding viscoelastic fluid at constant temperature. We derive an analytical expression for the probability density function of the energy exchanged with the fluid over a finite time interval, which implicitly involves the friction memory kernel that encodes the coupling with such a non-Markovian environment, and reduces to the well known expression for the heat distribution in a viscous fluid. We show that, while the odd moments of this distribution are zero, the even moments can be explicitly expressed in terms of the auto-correlation function of the particle position, which generally exhibits a non-mono-exponential decay when the fluid bath is viscoelastic. Our results are verified by experimental measurements for an optically-trapped colloidal bead in semidilute micellar and polymer solutions, finding and excellent agreement for all time intervals over which the energy exchange takes place.
description: 3 figures
Ehe und Familie im Rahmen der Sakramentalität der Kirche
Creators: name: Ouellet, Marc
Publisher: name: Internationale katholische Zeitschrift Communio
Year: 2022

description: Internationale katholische Zeitschrift Communio, Bd. 43 Nr. 5 (2014): Internationale katholische Zeitschrift Communio, Band 43, Heft 5
Reckoning with Food Apartheid: Lessons from U.S. Cities and Counties
Creators: name: Vinella-Brusher, Emma
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2023

description: In recent years, food justice activists and scholars have pushed to move away from the use of “food desert,” a misleading term that implies a naturally occurring phenomenon, and towards a “food apartheid” framing, which better reflects the intentionality and racially discriminatory approaches that have led to inequitable access to food seen in the U.S. today. Numerous cities and counties across the U.S. have established food justice programs to address these racialized inequities. Through interviews with staff members, this report explores the planning and policy interventions being implemented to fight food apartheid and sheds light on the language local governments are using to frame their work. These findings highlight the impact of language on how food insecurity is approached, and provide food apartheid-informed strategies for city and county staff to consider in this work.
Structured mesh material with gradient surface wettability for high-power-density proton exchange membrane fuel cells
Creators: name: Zhang, Guobin
name: Qu, Zhiguo
name: Wang, Ning
name: Wang, Xueliang
name: Wu, Yuhao
name: Wang, Yun
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Biophysics
subject: Space Science
subject: Chemical Sciences not elsewhere classified
subject: Cancer
subject: Hematology
subject: Plant Biology
subject: FOS: Biological sciences

description: A compact cell structure is highly desirable for next-generation high-power-density proton exchange membrane (PEM) fuel cell (>9.0 kW L−1). A novel integrated bipolar plate (BP) – gas diffusion layer (GDL) structure utilizing porous material is a promising configuration, which not only improves output power due to the reduced transport resistance but also reduces cell thickness. Herein, we propose a structured mesh material with gradient surface wettability for this cell structure, which is characterized by an ordered skeleton in the three-dimensional (3D) space with high structure design flexibility. It is experimentally found that the structured mesh material shows higher performance than serpentine and parallel flow fields. Meanwhile, 3D modeling work on an automobile fuel cell (cell area: 245.76 cm2) with the distribution zones of dot matrix structure for hydrogen, air and coolant flow, is conducted, and it is found that the structured mesh material effectively decreases the concentration and electric ohmic losses in comparison with the traditional “BP/flow field + GDL” structure, improving power density with uniform distribution characteristics. Moreover, the gradient wettability on the mesh surface helps promote the water detach the GDL and hold the residual liquid water in the top region, optimizing the water management.
Relugolix/Estradiol/Norethisterone (Norethindrone) Acetate: A Review in Symptomatic Uterine Fibroids
Creators: name: Syed, Yahiya Y.
Publisher: name: Adis Journals
Year: 2023
Subjects: Medicine

description: The Relugolix/Estradiol/Norethisterone (Norethindrone) Acetate in Uterine Fibroids Adis Drug Evaluation video abstract, script and image slide deck provide a brief overview of the mechanism of action of drug in indication, the administration regimen and the key efficacy and tolerability outcomes from clinical trials. The video abstract, script and slide deck, which have been peer reviewed and were uploaded to Figshare after the Relugolix/Estradiol/Norethisterone (Norethindrone) Acetate in Uterine Fibroids Adis Drug Evaluation was published, are sponsored by Myovant GmbH and Pfizer. The video abstract can be found here. © Springer Nature Switzerland AG 2023
Health, economic, and social implications of COVID-19 for China's rural population
Creators: name: Medina, A.
name: Guo, Y.
name: Zhou, H.
name: Abby, C.
name: Smith, K.
name: Ma, Y.
name: Friesen, D.
name: Rozelle, S.
name: Boswell, M.
name: Xue, H.
name: Dill, S.-E.
name: Loyalka, P.
name: Wang, H.
name: Sylvia, S.
name: Rose, N.
Publisher: name: Blackwell Publishing Ltd
Year: 2021

description: This study examines the effects of local and nationwide COVID-19 disease control measures on the health and economy of China's rural population. We conducted phone surveys with 726 randomly selected village informants across seven rural Chinese provinces in February 2020. Four villages (0.55%) reported infections, and none reported deaths. Disease control measures had been universally implemented in all sample villages. About 74% of informants reported that villagers with wage-earning jobs outside the village had stopped working due to workplace closures. A higher percentage of rural individuals could not work due to transportation, housing, and other constraints. Local governments had taken measures to reduce the impact of COVID-19. Although schools in all surveyed villages were closed, 71% of village informants reported that students were attending classes online. Overall, measures to control COVID-19 appear to have been successful in limiting disease transmission in rural communities outside the main epidemic area. Rural Chinese citizens, however, have experienced significant economic consequences from the disease control measures.
Multi techniques approach to identify and/or constrain radial velocity sub-stellar companions
Creators: name: Philipot, F.
name: Lagrange, A. -M.
name: Kiefer, F.
name: Rubini, P.
name: Delorme, P.
name: Chomez, A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Context. Although more than one thousand sub-stellar companions have already been detected with the radial velocity (RV) method, many new companions remain to be detected in the public RV archives. Aims. We wish to use the archival data obtained with the ESO/HARPS spectrograph to search for sub-stellar companions. Methods. We use the astronomic acceleration measurements of stars obtained with the Hipparcos and Gaia satellites to identify anomalies that could be explained by the presence of a companion. Once hints for a companion are found, we combine the RV data with absolute astrometry and, when available, relative astrometry data, using a Markov Chain Monte Carlo (MCMC) algorithm to determine the orbital parameters and mass of the companion. Results. We find and characterize three new brown dwarfs (GJ660.1 C, HD73256 B, and HD165131 B) and six new planets (HD75302 b, HD108202 b, HD135625 b, HD185283 b, HIP10337 b, and HIP54597 b) with separations between 1 and 6 au and masses between 0.6 and 100 MJup. We also constrain the orbital inclination of ten known sub-stellar companions and determine their true mass. Finally, we identify twelve new stellar companions. This shows that the analysis of proper motion anomalies allows for optimizing the RV search for sub-stellar companions and their characterization.
description: 72 pages, 61 figures, 13 tables, accepted for publication by A&A
EDP-convergence for nonlinear fast-slow reaction systems with detailed balance
Creators: name: Mielke, Alexander
name: Peletier, Mark A.
name: Stephan, Artur
Publisher: name: Weierstrass Institute
Year: 2020
Subjects: subject: Nonlinear reaction system with detailed balance
subject: fast-reaction limit
subject: gradient structure
subject: gradient system
subject: EDP-convergence
subject: energy-dissipation principle
subject: Gamma-convergence
subject: 49S05
subject: 47J30
subject: 92E20
subject: 34E13

description: We consider nonlinear reaction systems satisfying mass-action kinetics with slow and fast reactions. It is known that the fast-reaction-rate limit can be described by an ODE with Lagrange multipliers and a set of nonlinear constraints that ask the fast reactions to be in equilibrium. Our aim is to study the limiting gradient structure which is available if the reaction system satisfies the detailed-balance condition. The gradient structure on the set of concentration vectors is given in terms of the relative Boltzmann entropy and a cosh-type dissipation potential. We show that a limiting or effective gradient structure can be rigorously derived via EDP convergence, i.e. convergence in the sense of the Energy-Dissipation Principle for gradient flows. In general, the effective entropy will no longer be of Boltzmann type and the reactions will no longer satisfy mass-action kinetics.
Two-stage stochastic optimization of virtual power plant with wind power and uncertain demand
Creators: name: Zhang, Ningwei
name: Zhang, Yuli
name: Cheng, Zihan
name: Zhang, Lijun
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Biotechnology
subject: Information Systems not elsewhere classified
subject: Mathematical Sciences not elsewhere classified
subject: Plant Biology
subject: FOS: Biological sciences

description: The virtual power plant (VPP) has been recognized as an effective way to facilitate penetration of renewable and distributed energy resources in electricity markets. This paper introduces an adaptive curtailment strategy for a VPP comprising a wind power plant and uncertain demand, and explores the economic advantage of adaptively adjusting wind power curtailment. A two-stage stochastic model is proposed to deal with the uncertainties in wind power generation (WPG), load demand and market prices. In the model, the bid decision is made in the face of uncertainties in the first stage, while the control (curtailment) decision is made based on realized uncertain parameters in the second stage. This paper provides the closed-form optimal curtailment decision and characterizes the optimal bid decision. An efficient binary search algorithm is developed for optimizing the bid decision. By using a distribution-free approach, we show that as the prediction accuracy of WPG improves, the optimal bid decision converges toward the expected minimal power exchange, leading to a decrease in expected operational cost with diminishing marginal return. Numerical experiments based on real-world data demonstrate that compared with the existing greedy strategy and coordinated strategy, the proposed model can decrease the expected operational cost up to 16.9% and 11.0%, respectively.
Distributed optimization with quantization for computing Wasserstein barycenters
Creators: name: Krawchenko, Roman
name: Uribe, César A.
name: Gasnikov, Alexander
name: Dvurechensky, Pavel
Publisher: name: Weierstrass Institute
Year: 2020
Subjects: subject: Distributed convex optimization
subject: quantization
subject: optimal transport
subject: Wasserstein distance
subject: 90C25
subject: 90C30
subject: 90C06

description: We study the problem of the decentralized computation of entropy-regularized semi-discrete Wasserstein barycenters over a network. Building upon recent primal-dual approaches, we propose a sampling gradient quantization scheme that allows efficient communication and computation of approximate barycenters where the factor distributions are stored distributedly on arbitrary networks. The communication and algorithmic complexity of the proposed algorithm are shown, with explicit dependency on the size of the support, the number of distributions, and the desired accuracy. Numerical results validate our algorithmic analysis.
An Anisotropic Density Turbulence Model from the Sun to 1 au Derived From Radio Observations
Creators: name: Kontar, Eduard P.
name: Emslie, A. Gordon
name: Clarkson, Daniel L.
name: Chen, Xingyao
name: Chrysaphi, Nicolina
name: Azzollini, Francesco
name: Jeffrey, Natasha L. S.
name: Gordovskyy, Mykola
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Plasma Physics (physics.plasm-ph)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Solar radio bursts are strongly affected by radio-wave scattering on density inhomogeneities, changing their observed time characteristics, sizes, and positions. The same turbulence causes angular broadening and scintillation of galactic and extra-galactic compact radio sources observed through the solar atmosphere. Using large-scale simulations of radio-wave transport, the characteristics of anisotropic density turbulence from $0.1 \, R_\odot$ to $1$ au are explored. For the first time, a profile of heliospheric density fluctuations is deduced that accounts for the properties of extra-solar radio sources, solar radio bursts, and in-situ density fluctuation measurements in the solar wind at $1$ au. The radial profile of the spectrum-weighted mean wavenumber of density fluctuations (a quantity proportional to the scattering rate of radio-waves) is found to have a broad maximum at around $(4-7) \, R_\odot$, where the slow solar wind becomes supersonic. The level of density fluctuations at the inner scale (which is consistent with the proton resonance scale) decreases with heliocentric distance as $\langleδ{n_i}^2 \rangle (r) \simeq 2 \times 10^7 \, (r/R_\odot-1)^{-3.7}$ cm$^{-6}$. Due to scattering, the apparent positions of solar burst sources observed at frequencies between $0.1$ and $300$ MHz are computed to be essentially cospatial and to have comparable sizes, for both fundamental and harmonic emission. Anisotropic scattering is found to account for the shortest solar radio burst decay times observed, and the required wavenumber anisotropy is $q_\parallel/q_\perp =0.25-0.4$, depending on whether fundamental or harmonic emission is involved. The deduced radio-wave scattering rate paves the way to quantify intrinsic solar radio burst characteristics.
description: 27 pages, 12 figures
An efficient iterative technique for solving initial value problem for multidimensional partial differential equations
Creators: name: Rebenda, Josef
name: Šmarda, Zdeněk
Publisher: name: arXiv
Year: 2014
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 34A25, 65M12, 65M20

description: A new iterative technique is presented for solving of initial value problem for certain classes of multidimensional linear and nonlinear partial differential equations. Proposed iterative scheme does not require any discretization, linearization or small perturbations and therefore significantly reduces numerical computations. Rigorous convergence analysis of presented technique and an error estimate are included as well. Several numerical examples for high dimensional initial value problem for heat and wave type partial differential equations are presented to demonstrate reliability and performance of proposed iterative scheme.
Cognitive Enhancement als "Alltagsdoping"
Creators: name: Schlögl-Flierl, Kerstin
Publisher: name: Internationale katholische Zeitschrift Communio
Year: 2022

description: Internationale katholische Zeitschrift Communio, Bd. 43 Nr. 5 (2014): Internationale katholische Zeitschrift Communio, Band 43, Heft 5
Dynamic probabilistic constraints under continuous random distributions
Creators: name: González Grandón, Tatiana
name: Henrion, René
name: Pérez-Aros, Pedro
Publisher: name: Weierstrass Institute
Year: 2020
Subjects: subject: Dynamic probabilistic constraints
subject: chance constraints
subject: continuous distributions
subject: decision rules
subject: stochastic programming
subject: 90C15
subject: 49K45

description: The paper investigates analytical properties of dynamic probabilistic constraints (chance constraints). The underlying random distribution is supposed to be continuous. In the first part, a general multistage model with decision rules depending on past observations of the random process is analyzed. Basic properties like (weak sequential) (semi-) continuity of the probability function or existence of solutions are studied. It turns out that the results differ significantly according to whether decision rules are embedded into Lebesgue or Sobolev spaces. In the second part, the simplest meaningful two-stage model with decision rules from L 2 is investigated. More specific properties like Lipschitz continuity and differentiability of the probability function are considered. Explicitly verifiable conditions for these properties are provided along with explicit gradient formulae in the Gaussian case. The application of such formulae in the context of necessary optimality conditions is discussed and a concrete identification of solutions presented.
"Einer ist Arzt, sowohl fleischlich als auch geistlich"
Creators: name: Grünstäudl, Wolfgang
Publisher: name: Internationale katholische Zeitschrift Communio
Year: 2022

description: Internationale katholische Zeitschrift Communio, Bd. 43 Nr. 5 (2014): Internationale katholische Zeitschrift Communio, Band 43, Heft 5
Quantitative comparisons of VHE gamma-ray blazar flares with relativistic reconnection models
Creators: name: Jormanainen, J.
name: Hovatta, T.
name: Christie, I. M.
name: Lindfors, E.
name: Petropoulou, M.
name: Liodakis, I.
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The origin of extremely fast variability is one of the long-standing questions in the gamma-ray astronomy of blazars. While many models explain the slower, lower energy variability, they cannot easily account for such fast flares reaching hour-to-minute time scales. Magnetic reconnection, a process where magnetic energy is converted to the acceleration of relativistic particles in the reconnection layer, is a candidate solution to this problem. In this work, we employ state-of-the-art particle-in-cell simulations in a statistical comparison with observations of a flaring episode of a well-known blazar, Mrk 421, at very high energy (VHE, E > 100 GeV). We tested the predictions of our model by generating simulated VHE light curves that we compared quantitatively with methods that we have developed for a precise evaluation of theoretical and observed data. With our analysis, we can constrain the parameter space of the model, such as the magnetic field strength of the unreconnected plasma, viewing angle and the reconnection layer orientation in the blazar jet. Our analysis favours parameter spaces with magnetic field strength 0.1 G, rather large viewing angles (6-8 degrees), and misaligned layer angles, offering a strong candidate explanation for the Doppler crisis often observed in the jets of high synchrotron peaking blazars.
description: Accepted for publication in A&A
Dark Matter and Lepton Flavour Violation in a Hybrid Neutrino Mass Model
Creators: name: Deppisch, Frank F.
name: Huang, Wei-Chih
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We describe a hybrid model in which the light neutrino mass matrix receives both tree-level seesaw and loop-induced contributions. An additional U(1) gauge symmetry is used to stabilize the lightest right-handed neutrino as the Dark Matter candidate. After fitting the experimental neutrino data, we analyze and correlate the phenomenological consequences of the model, namely its impact on electroweak precision measurements, the Dark Matter relic abundance, lepton flavour violating rare decays and neutrinoless double beta decay. We find that natural realizations of the model characterized by large Yukawa couplings are compatible with and close to the current experimental limits.
description: 25 pages, 9 figures. V2: references added, typos corrected, version accepted by JHEP
Multiple Stellar Populations outside the tidal radius of NGC1851 through Gaia DR3 XP Spectra
Creators: name: Cordoni, Giacomo
name: Marino, Anna F.
name: Milone, Antonino P.
name: Dondoglio, Emanuele
name: Lagioia, Edoardo P.
name: Legnardi, Maria Vittoria
name: Mohandasan, Anjana
name: Jang, Sohee
name: Ziliotto, Tuila
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Ancient Galactic Globular Clusters (GCs) have long fascinated astronomers due to their intriguing multiple stellar populations characterized by variations in light-element abundances. Among these clusters, Type-II GCs stand out as they exhibit stars with large differences in heavy-element chemical abundances. These enigmatic clusters, comprising approximately 17\% of analyzed GCs with MPs, have been hypothesized to be the remnants of accreted dwarf galaxies. We focus on one of the most debated Type~II GCs, NGC1851, to investigate its MPs across a wide spatial range of up to 50 arcmin from the cluster center. By using Gaia DR3 low-resolution XP spectra, we generate synthetic photometry to perform a comprehensive analysis of the spatial distribution and kinematics of the canonical and anomalous populations within this GC. By using appropriate CMDs from the synthetic photometry in the BVI bands and in the $\rm f415^{25}$ band introduced in this work, we identify distinct stellar sequences associated with different heavy-element chemical composition. Our results suggest that the canonical and the anomalous populations reside both inside and outside the tidal radius of NGC1851, up to a distance that exceeds by 3.5 times its tidal radius. However, $\sim$80\% of stars outside the tidal radius are consistent with belonging to the canonical population, emphasizing its dominance in the cluster's outer regions. Remarkably, canonical stars exhibit a more circular on-sky morphology, while the anomalous population displays an elliptical shape. Furthermore, we delve into the kinematics of the multiple populations. Our results reveal a flat/increasing velocity dispersion profile in the outer regions and hints of a tangentially anisotropic motion in the outer regions, indicating a preference for stars to escape on radial orbits.
description: 13 pages, 10 figures, accepted for publication in A&A
Feasibility of dual-energy CBCT by spectral filtration of a dual-focus CNT x-ray source
Creators: name: Inscoe, C.R.
name: Lee, Y.Z.
name: Lu, J.
name: Spronk, D.
name: Zhou, O.
name: Puett, C.
name: Li, B.
name: Tyndall, D.A.
name: Luo, Y.
Publisher: name: Public Library of Science
Year: 2022

description: Cone beam computed tomography (CBCT) is now widely used in dentistry and growing areas of medical imaging. The presence of strong metal artifacts is however a major concern of using CBCT especially in dentistry due to the presence of highly attenuating dental restorations, fixed appliances, and implants. Virtual monoenergetic images (VMIs) synthesized from dual energy CT (DECT) datasets are known to reduce metal artifacts. Although several techniques exist for DECT imaging, they in general come with significantly increased equipment cost and not available in dental clinics. The objectives of this study were to investigate the feasibility of developing a low-cost dual energy CBCT (DE-CBCT) by retrofitting a regular CBCT scanner with a carbon nanotube (CNT) x-ray source with dual focal spots and corresponding low-energy (LE) and high-energy (HE) spectral filters. A testbed with a CNT field emission x-ray source (NuRay Technology, Chang Zhou, China), a flat panel detector (Teledyne, Waterloo, Canada), and a rotating object stage was used for this feasibility study. Two distinct polychromatic x-ray spectra with the mean photon energies of 66.7keV and 86.3keV were produced at a fixed 120kVp x-ray tube voltage by using Al+Au and Al+Sn foils as the respective LE and HE filters attached to the exist window of the x-ray source. The HE filter attenuated the x-ray photons more than the LE filter. The calculated post-object air kerma rate of the HE beam was 31.7% of the LE beam. An anthropomorphic head phantom (RANDO, Nuclear Associates, Hicksville, NY) with metal beads was imaged using the testbed and the images were reconstructed using an iterative volumetric CT reconstruction algorithm. The VMIs were synthesized using an image-domain basis materials decomposition method with energy ranging from 30 to 150keV. The results were compared to the reconstructed images from a single energy clinical dental CBCT scanner (CS9300, Carestream Dental, Atlanta, GA). A significant reduction of the metal artifacts was observed in the VMI images synthesized at high energies compared to those from the same object imaged by the clinical dental CBCT scanner. The ability of the CNT x-ray source to generate the output needed to compensate the reduction of photon flux due to attenuation from the spectral filters and to maintain the CT imaging time was evaluated. The results demonstrated the feasibility of DE-CBCT imaging using the proposed approach. Metal artifact reduction was achieved in VMIs synthesized. The x-ray output needed for the proposed DE-CBCT can be generated by a fixed-anode CNT x-ray source.
Biodiesel production and selected fuel qualities from prospective non-edible oils: Hevea brasiliensis, Madhuca longifolia, Azadirachta indica, and Gossypium hirsutum
Creators: name: Khan, Inam Ullah
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Biotechnology
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: FOS: Biological sciences
subject: Biological Sciences not elsewhere classified

description: Biodiesel predominantly originates from edible oil. Exploring non-edible oil resources is crucial to biodiesel manufacturing’s commercial viability and food security. This study examines four non-edible seed oils Hevea brasiliensis, Madhuca longifolia, Azadirachta indica, and Gossypium hirsutum as biofuel feedstocks. This study optimized reaction parameters to improve base-catalyzed transesterification, oil extraction and biodiesel synthesis. The produced esters were identified by nuclear magnetic resonance, Fourier transform infrared, and gas chromatography mass spectrometry. Elements composition was determined using inductively coupled plasma-optical emission spectrometry and elemental analyzer. The biofuel’s physicochemical properties met American Society for Testing and Materials and European standards. The maximum amount of crude oil was seen in Hevea brasiliensis using the soxhlet extraction process, ranging from 52-63%. This was followed by Madhuca longifolia 38-55%, Azadirachta indica 24-33%, and Gossypium hirsutum with 19-27%. The density of the plant sources exhibited a range of 0.88-0.90 g/cm3 @ 15 °C, while the kinematic viscosity showed a range of 3.2-4.1 mm2/s. The elemental composition of biodiesel, expressed as percentages of carbon, hydrogen, nitrogen, and oxygen, varied between the ranges of 70.52-76.30, 11.25-14.02, 1.18-2.75, and 9.11-13%, respectively. Since they may be grown in infertile and unproductive settings, these non-consumable seeds are cost-effective for renewable energy. They also help solve the energy situation by boosting biodiesel production..
3D mapping of intensity field about the focus of a micrometer scale parabolic mirror
Creators: name: McDonald, Alison
name: McConnell, Gail
name: Cox, David C.
name: Riis, Erling
name: Griffin, Paul F.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We report on the fabrication and diffraction-limited characterization of parabolic focusing micromirrors. Sub - micron beam waists are measured for mirrors with 10 μm radius aperture and measured fixed focal lengths in the range from 24 μm to 36 μm. Optical characterization of the 3D intensity in the nearfield produced when the device is illuminated with collimated light is performed using a modified confocal microscope. Results are compared directly with angular spectrum simulations, yielding strong agreement between experiment and theory, and identifying the competition between diffraction and focusing in the regime probed.
description: 7 pages, 5 figures. Accepted to Optics Express
Applying synthetic radiography to intraoral tomosynthesis: A step towards achieving 3D imaging in the dental clinic
Creators: name: Zhou, O.
name: Gaalaas, L.R.
name: Inscoe, C.R.
name: Platin, E.
name: Hilton, R.L.
name: Lu, J.
name: Perrone, L.
name: Puett, S.
name: Puett, C.
name: Regan Anderson, M.W.
Publisher: name: British Institute of Radiology
Year: 2021

description: objectives: A practical approach to three-dimensional (3D) intraoral imaging would have many potential applications in clinical dentistry. Stationary intraoral tomosynthesis (sIOT) is an experimental 3D imaging technology that holds promise. The purpose of this study was to explore synthetic radiography as a tool to improve the clinical utility of the images generated by an sIOT scan. Methods: Extracted tooth specimens containing either caries adjacent to restorations (CAR) or vertical root fractures (VRF) were imaged by sIOT and standard dental radiography devices. Qualitative assessments were used to compare the conspicuity of these pathologies in the standard radiographs and in a set of multi-view synthetic radiographs generated from the information collected by sIOT. Results: The sIOT-based synthetic 2D radiographs contained less artefact than the image slices in the reconstructed 3D stack, which is the conventional approach to displaying information from a tomosynthesis scan. As a single sIOT scan can be used to generate synthetic radiographs from multiple viewing angles, the interproximal space was less likely to be obscured in the synthetic images compared to the standard radiograph. Additionally, the multi-view synthetic radiographs can potentially improve the display of CAR and VRFs as compared to a single standard radiograph. conclusions: This preliminary experience combining synthetic radiography and sIOT in extracted tooth models is encouraging and supports the ongoing study of this promising approach to 3D intraoral imaging with many potential applications.
337. Comparative efficacy and safety of glucocorticoid regimens in patients with ANCA-associated vasculitis: a systematic review
Creators: name: Yingqi Xiao1
Publisher: name: Zenodo
Year: 2022
Subjects: Vasculitis
ANCA
Abstracts
Giant Cell Arthritis
MPA
GPA
EGPA
Takayasu
IgA vasculitis

description: Background/Objectives: To compare the efficacy and safety of alternative glucocorticoids (GC) regimens as induction therapy for patients with antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis. Methods: Systematic review of randomized controlled trial (RCTs). Data sources included Medline, Embase, Clinicaltrials.gov and Cochrane Central Register of Controlled Trials up to 10 April 2020. RCTs comparing two (or more) different dose regimens of GC in ANCA-associated vasculitis during induction of remission, regardless of other therapies were eligible. Pairs of reviewers independently screened records, extracted data and assessed risk of bias. Two reviewers rated certainty of evidence using the Grading of Recommendations Assessment, Development, and Evaluation approach. Results: Of 3912 records identified, full text of two records met the eligibility criteria. Due to the heterogeneity of the populations and dose regimens of glucocorticoids between the two trials, we descriptively presented the two RCTs and did not combine the results using meta-analysis. Compared with the standard-dose regimen, the reduced-dose regimen of GC in both trials may reduce death, risk difference [RD] ranged from -1.7% to -2.1% between the two trials, low certainty), and end-stage kidney disease was not increased (RD ranged from -1.5% to 0.4% between the two trials, moderate certainty). The reduced-dose regimen probably has an important reduction in serious infections at 1 year (RD ranged from -12.8% to -5.9% between the two trials, moderate certainty). The reduced-dose regimen of glucocorticoids probably has trivial or no effect in disease remission, relapse or health related quality of life (moderate to high certainty). Conclusions: Reduced-dose regimens vary but compared to regimens considered standard-dose, they may reduce the risk of death serious infections without detrimental effects on the risk of end-stage kidney disease, remission, relapse, or health related quality of life in selected populations. Disclosures: None
Electroweak naturalness in three-flavour Type I see-saw and implications for leptogenesis
Creators: name: Clarke, Jackson D.
name: Foot, Robert
name: Volkas, Raymond R.
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In the Type I see-saw model, the naturalness requirement that corrections to the electroweak $μ$ parameter not exceed 1 TeV results in a rough bound on the lightest right-handed neutrino mass, $M_{N_1}\lesssim 3\times 10^7$ GeV. In this letter we derive generic bounds applicable in any three-flavour Type I see-saw model. We find $M_{N_1}\lesssim 4\times 10^7$ GeV and $M_{N_2}\lesssim 7\times 10^7$ GeV. In the limit of one massless neutrino, there is no naturalness bound on $M_{N_3}$ in the Poincare protected decoupling limit. Our results confirm that no Type I see-saw model can explain the observed neutrino masses and baryogenesis via hierarchical ($N_1$-, $N_2$-, or $N_3$-dominated) thermal leptogenesis while remaining completely natural.
description: 4 pages, 3 figures, v2 minor changes