cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Influence of chirp and carrier-envelope phase on non-integer high-harmonic generation
Creators: name: Graml, Maximilian
name: Nitsch, Maximilian
name: Seith, Adrian
name: Evers, Ferdinand
name: Wilhelm, Jan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: High harmonic generation (HHG) is a versatile technique for probing ultrafast electron dynamics. While HHG is sensitive to the electronic properties of the target, HHG also depends on the waveform of the laser pulse. As is well known, (peak) positions, $ω$, in the high-harmonic spectrum can shift when the carrier envelope phase (CEP), $φ$ is varied. We derive formulae describing the corresponding parametric dependencies of CEP shifts; in particular, we have a transparent result for the (peak) shift, $dω/dφ= {-} 2 \bar{\mathfrak f}' ω/ω_0$, where $ω_0$ describes the fundamental frequency and $\bar{\mathfrak f}'$ characterizes the chirp of the driving laser pulse. We compare the analytical formula to full-fledged numerical simulations finding only 17 % average relative absolute deviation in $dω/dφ$. Our analytical result is fully consistent with experimental observations.
XXL-HSC: The link between AGN activity and star formation in the Early Universe ($z\geqslant3.5$)
Creators: name: Pouliasis, E.
name: Mountrichas, G.
name: Georgantopoulos, I.
name: Ruiz, A.
name: Gilli, R.
name: Koulouridis, E.
name: Akiyama, M.
name: Ueda, Y.
name: Garrel, C.
name: Nagao, T.
name: Paltani, S.
name: Pierre, M.
name: Toba, Y.
name: Vignali, C.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: In this work, we aimed at investigating the star formation rate of active galactic nuclei host galaxies in the early Universe. To this end, we constructed a sample of 149 luminous ($\rm L_{2-10keV} > 10^{44}\,erg\,s^{-1}$) X-ray AGNs at $\rm z \geq3.5$ selected in three fields with different depths and observed areas (Chandra COSMOS Legacy survey, XMM-XXL North and eFEDS). We built their spectral energy distributions (SED) using available multi-wavelength photometry from X-rays up to far-IR. Then, we estimated the stellar mass, M$_{*}$, and the SFR of the AGNs using the X-CIGALE SED fitting algorithm. After applying several quality criteria, we ended up with 89 high-z sources. More than half (55\%) of the X-ray sample have spectroscopic redshifts. Based on our analysis, our high-z X-ray AGNs live in galaxies with median $\rm M_{*}=5.6 \times10^{10}~M_\odot$ and $\rm SFR_{*}\approx240\,M_\odot yr^{-1}$. The majority of the high-z sources ($\sim89$\%) were found inside or above the main sequence (MS) of star-forming galaxies. Estimation of the normalised SFR, $\rm SFR_{NORM}$, defined as the ratio of the SFR of AGNs to the SFR of MS galaxies, showed that the SFR of AGNs is enhanched by a factor of $\sim 1.8$ compared to non-AGN star-forming systems. Combining our results with previous studies at lower redshifts, we confirmed that $\rm SFR_{NORM}$ does not evolve with redshift. Using the specific BHAR (i.e., $\rm L_X$ divided by $\rm M_{*}$), $\rm λ_{BHAR}$, that can be used as a tracer of the Eddington ratio, we found that the bulk of AGNs that lie inside or above the MS have higher specific accretion rates compared to sources below the MS. Finally, we found indications that the SFR of the most massive AGN host galaxies ($\rm log\,(M_{*}/ M_\odot) >10^{11.5-12}$) remains roughly constant as a function of M$_*$, in agreement with the SFR of MS star-forming galaxies.
description: Accepted for publication in A&A. 19 pages, 12 figures (+6 in Appendix), 4 tables
Strong generators in tensor triangulated categories
Creators: name: Steen, Johan
name: Stevenson, Greg
Publisher: name: arXiv
Year: 2014
Subjects: subject: Category Theory (math.CT)
subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics

description: We show that in an essentially small rigid tensor triangulated category with connected Balmer spectrum there are no proper non-zero thick tensor ideals admitting strong generators. This proves, for instance, that the category of perfect complexes over a commutative ring without non-trivial idempotents has no proper non-zero thick subcategories that are strongly generated.
description: 9 pages, comments welcome
The MOSDEF Survey: Towards a Complete Census of the z ~ 2.3 Star-forming Galaxy Population
Creators: name: Runco, Jordan N.
name: Shapley, Alice E.
name: Sanders, Ryan L.
name: Kriek, Mariska
name: Reddy, Naveen A.
name: Coil, Alison L.
name: Mobasher, Bahram
name: Siana, Brian
name: Topping, Michael W.
name: Freeman, William R.
name: Shivaei, Irene
name: Azadi, Mojegan
name: Price, Sedona H.
name: Leung, Gene C. K.
name: Fetherolf, Tara
name: de Groot, Laura
name: Zick, Tom
name: Fornasini, Francesca M.
name: Barro, Guillermo
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We analyze the completeness of the MOSDEF survey, in which z ~ 2 galaxies were selected for rest-optical spectroscopy from well-studied HST extragalactic legacy fields down to a fixed rest-optical magnitude limit (H_AB = 24.5). The subset of z ~ 2 MOSDEF galaxies with high signal-to-noise (S/N) emission-line detections analyzed in previous work represents a small minority (<10%) of possible z ~ 2 MOSDEF targets. It is therefore crucial to understand how representative this high S/N subsample is, while also more fully exploiting the MOSDEF spectroscopic sample. Using spectral-energy-distribution (SED) models and rest-optical spectral stacking, we compare the MOSDEF z ~ 2 high S/N subsample with the full MOSDEF sample of z ~ 2 star-forming galaxies with redshifts, the latter representing an increase in sample size of more than a factor of three. We find that both samples have similar emission-line properties, in particular in terms of the magnitude of the offset from the local star-forming sequence on the [N II] BPT diagram. There are small differences in median host galaxy properties, including the stellar mass (M_*), star-formation rate (SFR) and specific SFR (sSFR), and UVJ colors; however, these offsets are minor considering the wide spread of the distributions. Using SED modeling, we also demonstrate that the sample of z ~ 2 star-forming galaxies observed by the MOSDEF survey is representative of the parent catalog of available such targets. We conclude that previous MOSDEF results on the evolution of star-forming galaxy emission-line properties were unbiased relative to the parent z ~ 2 galaxy population.
description: 18 pages, 10 figures, 3 tables
Chris L. Smith, Architecture After Deleuze and Guattari, Bloomsbury Academic, London/New  York/Oxford/New Delhi/Sydney, 2023.
Creators: name: Görgül, Emine
Publisher: name: Institute for Philosophy and Social Theory (IFDT), University of Belgrade
Year: 2025

description: Book Review : Chris L. Smith, Architecture After Deleuze and Guattari, Bloomsbury Academic, London/New  York/Oxford/New Delhi/Sydney, 2023.
The forward-backward asymmetry and differences of partial moments in inclusive semileptonic B decays
Creators: name: Herren, Florian
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Global fits to moments of kinematic distributions measured in inclusive semileptonic $B\rightarrow X_c l ν_l$ enable the determination of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$ together with non-perturbative matrix elements of the heavy quark expansion. In current fits, only two distinct kinematic distributions are employed and, as a consequence, higher moments of these distributions need to be taken into account to extract the relevant non-perturbative matrix elements. The moments of a given distribution are highly correlated and experimental uncertainties increase for higher moments. To address these issues, Turczyk suggested the inclusion of the charged lepton forward-backward asymmetry $\mathcal{A}_{FB}$ in global fits, since it provides information on non-perturbative parameters beyond the commonly used moments. It is possible to construct differences of partial moments of kinematic distributions, which can provide additional information on the non-perturbative parameters beyond $\mathcal{A}_{FB}$ and are studied in this work for the first time. Further, experimental cuts on the four-momentum transfer square are studied and are shown to preserve the shape of the angular distribution, in contrast to commonly used cuts on the lepton energy. Finally, the impact of final-state radiation and experimental lepton identification requirements on measurements of $\mathcal{A}_{FB}$ and differences of partial moments are discussed.
description: Fixed some numbers, conclusions unchanged
Autoregulation of Cerebral Blood Flow to Changes in Arterial Pressure in Mild Alzheimer's Disease
Creators: name: Zazulia, Allyson R
name: Morris, John C
name: Videen, Tom O
name: Powers, William J
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Studies in transgenic mice overexpressing amyloid precursor protein (APP) demonstrate impaired autoregulation of cerebral blood flow (CBF) to changes in arterial pressure and suggest that cerebrovascular dysfunction may be critically important in the development of pathological Alzheimer's disease (AD). Given the relevance of such a finding for guiding hypertension treatment in the elderly, we assessed autoregulation in individuals with AD. Twenty persons aged 75±6 years with very mild or mild symptomatic AD (Clinical Dementia Rating 0.5 or 1.0) underwent 15O-positron emission tomography (PET) CBF measurements before and after mean arterial pressure (MAP) was lowered from 107±13 to 92±9 mm Hg with intravenous nicardipine; 11C-PIB-PET imaging and magnetic resonance imaging (MRI) were also obtained. There were no significant differences in mean CBF before and after MAP reduction in the bilateral hemispheres (−0.9±5.2 mL per 100 g per minute, P=0.4, 95% confidence interval (CI)=−3.4 to 1.5), cortical borderzones (−1.9±5.0 mL per 100 g per minute, P=0.10, 95% CI=−4.3 to 0.4), regions of T2W-MRI-defined leukoaraiosis (−0.3±4.4 mL per 100 g per minute, P=0.85, 95% CI=−3.3 to 3.9), or regions of peak 11C-PIB uptake (−2.5±7.7 mL per 100 g per minute, P=0.30, 95% CI=−7.7 to 2.7). The absence of significant change in CBF with a 10 to 15 mm Hg reduction in MAP within the normal autoregulatory range demonstrates that there is neither a generalized nor local defect of autoregulation in AD.
Massive young stellar objects in the Local Group spiral galaxy M33 identified using machine learning
Creators: name: Kinson, David A.
name: Oliveira, Joana M.
name: van Loon, Jacco Th.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present a supervised machine learning classification of stellar populations in the Local Group spiral galaxy M\,33. The Probabilistic Random Forest (PRF) methodology, previously applied to populations in NGC\,6822, utilises both near and far-IR classification features. It classifies sources into nine target classes: young stellar objects (YSOs), oxygen- and carbon-rich asymptotic giant branch stars, red giant branch and red super-giant stars, active galactic nuclei, blue stars (e.g. O-, B- and A-type main sequence stars), Wolf-Rayet stars and Galactic foreground stars. Across 100 classification runs the PRF classified 162,746 sources with an average estimated accuracy of $\sim$\,86\,per\,cent, based on confusion matrices. We identified 4985 YSOs across the disk of M\,33, applying a density-based clustering analysis to identify 68 star forming regions (SFRs) primarily in the galaxy's spiral arms. SFR counterparts to known H\,{\sc ii} regions were recovered, with $\sim$\,91\,per\,cent of SFRs spatially coincident with giant molecular clouds identified in the literature. Using photometric measurements, as well as SFRs in NGC\,6822 with an established evolutionary sequence as a benchmark, we employed a novel approach combining ratios of [H$α$]$/$[24$μ$m] and [250$μ$m]$/$[500$μ$m] to estimate the relative evolutionary status of all M\,33 SFRs. Masses were estimated for each YSO ranging from 6\,$-$\,27\,M$_\odot$. Using these masses, we estimate star formation rates based on direct YSO counts of 0.63\,M$_\odot$\,yr$^{-1}$ in M\,33's SFRs, 0.79\,$\pm$\,0.16\,M$_\odot$\,yr$^{-1}$ in its centre and 1.42\,$\pm$\,0.16\,M$_\odot$\,yr$^{-1}$ globally.
description: 21 pages, 33 figures
A Novel Automated Lazy Learning QSAR (ALL-QSAR) Approach:  Method Development, Applications, and Virtual Screening of Chemical Databases Using Validated ALL-QSAR Models
Creators: name: Kohn, Harold
name: Zhang, Shuxing
name: Golbraikh, Alexander
name: Tropsha, Alexander
name: Oloff, Scott
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: A novel Automated Lazy Learning Quantitative Structure-Activity Relationship (ALL-QSAR) modeling approach has been developed based on the lazy learning theory. The activity of a test compound is predicted from locally weighted linear regression model using chemical descriptors and biological activity of the training set compounds most chemically similar to this test compound. The weights with which training set compounds are included in the regression depend on the similarity of those compounds to a test compound. We have applied the ALL-QSAR method to several experimental chemical datasets including 48 anticonvulsant agents with known ED50 values, 48 dopamine D1-receptor antagonists with known competitive binding affinities (Ki), and a Tetrahymena pyriformis dataset containing 250 phenolic compounds with toxicity IGC50 values. When applied to database screening, models developed for anticonvulsant agents identified several known anticonvulsant compounds that were not only absent in the training set but highly chemically dissimilar to the training set compounds. This initial success indicates that ALL-QSAR can be further exploited as a general tool for accurate bioactivity prediction and database screening in drug design and discovery. Due to its local nature, the ALL-QSAR approach appears to be especially well suited for the development of highly predictive models for the sparse or unevenly distributed datasets.
Two-stream Plasma Instability as a Potential Mechanism for Particle Escape from the Venusian Ionosphere
Creators: name: Dey, Suman
name: Ghosh, Saptarshi
name: Maity, Debjit
name: De, Ayanabha
name: Chandra, Swarniv
Publisher: name: arXiv
Year: 2022
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: In this work we investigate the possibility of two-stream instability in the Venusian atmosphere to lead to momentum transfer to subsequent escape of Hydrogen and Oxygen ions from the ionosphere. We employ the hydrodynamic model and obtain the linear dispersion relation from which the two-stream instability is studied. Further the interaction of solar wind with the ions of Venus ionosphere from which the instability sets in, has been studied with the data from ASPERA-4 of Venus Express (VEX). The data supports the fact that the two-stream instability can provide sufficient energy to accelerate ions to escape velocity of the planet.
description: 8 pages, 5 figures
Chimera states in a population of identical oscillators under planar cross-coupling
Creators: name: Hens, C. R.
name: Mishra, A.
name: Roy, P. K.
name: Sen, A.
name: Dana, S. K.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: We report the existence of a chimera state in an assembly of identical nonlinear oscillators that are globally linked to each other in a simple planar cross-coupled form. The rotational symmetry breaking of the coupling term appears to be responsible for the emergence of these collective states that display a characteristic coexistence of coherent and incoherent behaviour. Our finding, seen in both a collection of van der Pol oscillators and chaotic Rossler oscillators, further simplifies the existence criterion for chimeras and thereby broadens the range of their applicability to real world situations.
Patrik Schumacher, Tectonism: Architecture  for the Twenty-First Century, Images  Publishing/The Arts Bridge, Melbourne, 2023.
Creators: name: Baldwin, Peter J
Publisher: name: Institute for Philosophy and Social Theory (IFDT), University of Belgrade
Year: 2025

description: Book Review : Patrik Schumacher, Tectonism: Architecture for the Twenty-First Century, Images Publishing/The Arts Bridge, Melbourne, 2023.
Chemometric Analysis of Ligand Receptor Complementarity:  Identifying Complementary Ligands Based on Receptor Information (CoLiBRI)
Creators: name: Tropsha, Alexander
name: Breneman, Curt
name: Sukumar, Nagamani
name: Zhang, Shuxing
name: Oloff, Scott
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: We have developed a novel structure-based approach to search for Complimentary Ligands Based on Receptor Information (CoLiBRI). CoLiBRI is based on the representation of both receptor binding sites and their respective ligands in a space of universal chemical descriptors. The binding site atoms involved in the interaction with ligands are identified by the means of computational geometry technique known as Delaunay tessellation as applied to x-ray characterized ligand-receptor complexes. TAE/RECON1 multiple chemical descriptors are calculated independently for each ligand as well as for its active site atoms. The representation of both ligands and active sites using chemical descriptors allows the application of well-known chemometric techniques in order to correlate chemical similarities between active sites and their respective ligands. From these calculations, we have established a protocol to map patterns of nearest neighbor active site vectors in a multidimensional TAE/RECON space onto those of their complementary ligands, and vice versa. This protocol affords the prediction of a virtual complementary ligand vector in the ligand chemical space from the position of a known active site vector. This prediction is followed by chemical similarity calculations between this virtual ligand vector and those calculated for molecules in a chemical database to identify real compounds most similar to the virtual ligand. Consequently, the knowledge of the receptor active site structure affords straightforward and efficient identification of its complementary ligands in large databases of chemical compounds using rapid chemical similarity searches. Conversely, starting from the ligand chemical structure, one may identify possible complementary receptor cavities as well. We have applied the CoLiBRI approach to a dataset of 800 x-ray characterized ligand receptor complexes in the PDBbind database2. Using a k nearest neighbor (kNN) pattern recognition approach and variable selection, we have shown that knowledge of the active site structure affords identification of its complimentary ligand among the top 1% of a large chemical database in over 90% of all test active sites when a binding site of the same protein family was present in the training set. In the case where test receptors are highly dissimilar and not present among the receptor families in the training set, the prediction accuracy is decreased; however CoLiBRI was still able to quickly eliminate 75% of the chemical database as improbable ligands. The CoLiBRI approach provides an efficient prescreening tool for large chemical databases prior to traditional, yet much more computationally intensive, three-dimensional docking approaches.
Type Ia Supernova Spectral Features in the Context of Their Host Galaxy Properties
Creators: name: Pan, Y. -C.
name: Sullivan, M.
name: Maguire, K.
name: Gal-Yam, A.
name: Hook, I. M.
name: Howell, D. A.
name: Nugent, P. E.
name: Mazzali, P. A.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We analyse spectroscopic measurements of 122 type Ia supernovae (SNe Ia) with z<0.09 discovered by the Palomar Transient Factory, focusing on the properties of the Si II 6355 and Ca II `near-infrared triplet' absorptions. We examine the velocities of the photospheric Si II 6355, and the velocities and strengths of the photospheric and high-velocity Ca II, in the context of the stellar mass (Mstellar) and star-formation rate (SFR) of the SN host galaxies, as well as the position of the SN within its host. We find that SNe Ia with faster Si II 6355 tend to explode in more massive galaxies, with the highest velocity events only occuring in galaxies with Mstellar > 3*10^9 solar mass. We also find some evidence that these highest velocity SNe Ia explode in the inner regions of their host galaxies, similar to the study of Wang et al. (2013), although the trend is not as significant in our data. We show that these trends are consistent with some SN Ia spectral models, if the host galaxy stellar mass is interpreted as a proxy for host galaxy metallicity. We study the strength of the high-velocity component of the Ca II near-IR absorption, and show that SNe Ia with stronger high-velocity components relative to photospheric components are hosted by galaxies with low stellar mass, blue colour, and a high sSFR. Such SNe are therefore likely to arise from the youngest progenitor systems. This argues against a pure orientation effect being responsible for high-velocity features in SN Ia spectra and, when combined with other studies, is consistent with a scenario where high-velocity features are related to an interaction between the SN ejecta and circumstellar medium (CSM) local to the SN.
description: Submitted to MNRAS
Collective Dynamics of Interacting Particles in Unsteady Flows
Creators: name: Abedi, Maryam
name: Jalali, Mir Abbas
Publisher: name: arXiv
Year: 2014
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Dynamical Systems (math.DS)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We use the Fokker-Planck equation and its moment equations to study the collective behavior of interacting particles in unsteady one-dimensional flows. Particles interact according to a long-range attractive and a short-range repulsive potential field known as Morse potential. We assume Stokesian drag force between particles and their carrier fluid, and find analytic single-peaked traveling solutions for the spatial density of particles in the catastrophic phase. In steady flow conditions the streaming velocity of particles is identical to their carrier fluid, but we show that particle streaming is asynchronous with an unsteady carrier fluid. Using linear perturbation analysis, the stability of traveling solutions is investigated in unsteady conditions. It is shown that the resulting dispersion relation is an integral equation of the Fredholm type, and yields two general families of stable modes: singular modes whose eigenvalues form a continuous spectrum, and a finite number of discrete global modes. Depending on the value of drag coefficient, stable modes can be over-damped, critically damped, or decaying oscillatory waves. The results of linear perturbation analysis are confirmed through the numerical solution of the fully nonlinear Fokker-Planck equation.
description: 21 Pages, 5 Figures
MedusaScore: An Accurate Force Field-Based Scoring Function for Virtual Drug Screening
Creators: name: Vondrasek, Jiri
name: Dokholyan, Nikolay V.
name: Yin, Shuangye
name: Biedermannova, Lada
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Virtual screening is becoming an important tool for drug discovery. However, the application of virtual screening has been limited by the lack of accurate scoring functions. Here, we present a novel scoring function, MedusaScore, for evaluating protein-ligand binding. MedusaScore is based on models of physical interactions that include van der Waals, solvation and hydrogen bonding energies. To ensure the best transferability of the scoring function, we do not use any protein-ligand experimental data for parameter training. We then test the MedusaScore for docking decoy recognition and binding affinity prediction and find superior performance compared to other widely used scoring functions. Statistical analysis indicates that one source of inaccuracy of MedusaScore may arise from the unaccounted entropic loss upon ligand binding, which suggests avenues of approach for further MedusaScore improvement.
Inferring the nuclear symmetry energy at supra saturation density from neutrino cooling
Creators: name: Malik, Tuhin
name: Agrawal, B. K.
name: Providência, Constança
Publisher: name: arXiv
Year: 2022
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: An ambitious goal of the astrophysical community is not only to constrain the equation of state (EOS) of neutron star (NS) matter by confronting it with astrophysics observations, but ultimately also to infer the NS composition. Nevertheless, the composition of the NS core is likely to remain uncertain unless we have an accurate determination of the nuclear symmetry energy at supra saturation density ($ρ>ρ_0$). We investigate how the nucleonic direct Urca (dUrca) processes can be used as an effective probe to constraint the high density nuclear symmetry energy. A large number of minimally constrained EOSs has been constructed by applying a Bayesian approach to study the correlations of the symmetry energy at different densities with a few selected properties of a NS. The nuclear symmetry energy above the baryon density 0.5 fm$^{-3}$ ($\sim 3 ρ_0$) is found to be strongly correlated with NS mass at which the onset of nucleonic dUrca neutrino cooling takes place in the core. This allows us to constrain the high density behavior of nuclear symmetry energy within narrow bounds. {The pure neutron matter pressure constraint from chiral effective field theory rules out the onset of nucleonic dUrca in stars with a mass $\lesssim$ 1.4 $M_\odot$.} The onset of dUrca inside 1.6 M$_\odot$ to 1.8 M$_\odot$ NS implies a slope of the symmetry energy $L$ at $\sim 2.5~ρ_0$, respectively, between 54 and 48 MeV.
description: 6 pages, 3 figures and 1 supplemental material
Complexity through Translations for Modal Logic with Recursion
Creators: name: Aceto, Luca
name: Achilleos, Antonis
name: Anastasiadi, Elli
name: Francalanza, Adrian
name: Ingolfsdottir, Anna
Publisher: name: arXiv
Year: 2022
Subjects: subject: Logic in Computer Science (cs.LO)
subject: FOS: Computer and information sciences
subject: F.4.1; I.2.4

description: This paper studies the complexity of classical modal logics and of their extension with fixed-point operators, using translations to transfer results across logics. In particular, we show several complexity results for multi-agent logics via translations to and from the mu-calculus and modal logic, which allow us to transfer known upper and lower bounds. We also use these translations to introduce a terminating tableau system for the logics we study, based on Kozen's tableau for the mu-calculus, and the one of Fitting and Massacci for modal logic.
description: In Proceedings GandALF 2022, arXiv:2209.09333
Rapid Flexible Docking Using a Stochastic Rotamer Library of Ligands
Creators: name: Dokholyan, Nikolay V.
name: Ding, Feng
name: Yin, Shuangye
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Existing flexible docking approaches model the ligand and receptor flexibility either separately or in a loosely-coupled manner, which captures the conformational changes inefficiently. Here, we propose a flexible docking approach, MedusaDock, which models both ligand and receptor flexibility simultaneously with sets of discrete rotamers. We develop an algorithm to build the ligand rotamer library “on-the-fly” during docking simulations. MedusaDock benchmarks demonstrate a rapid sampling efficiency and high prediction accuracy in both self-docking (to the co-crystallized state) and cross-docking (to a state co-crystallized with a different ligand), the latter of which mimics the virtual-screening procedure in computational drug discovery. We also perform a virtual-screening test of four flexible kinase targets including cyclin-dependent kinase 2, vascular endothelial growth factor receptor 2, HIV reverse transcriptase, and HIV protease. We find significant improvements of virtual-screening enrichments when compared to rigid-receptor methods. The predictive power of MedusaDock in cross-docking and preliminary virtual-screening benchmarks highlights the importance to model both ligand and receptor flexibility simultaneously in computational docking.
Improving the astrometric performance of VLTI-PRIMA
Creators: name: Woillez, J.
name: Abuter, R.
name: Andolfato, L.
name: Berger, J. P.
name: Bonnet, H.
name: Delplancke, F.
name: Derie, F.
name: Di Lieto, N.
name: Guniat, S.
name: Mérand, A.
name: Duc, T. Phan
name: Schmid, C.
name: Schuhler, N.
name: Henning, T.
name: Launhardt, R.
name: Pepe, F.
name: Queloz, D.
name: Quirrenbach, A.
name: Reffert, S.
name: Sahlmann, S.
name: Segransan, D.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: In the summer of 2011, the first on-sky astrometric commissioning of PRIMA-Astrometry delivered a performance of 3 m'' for a 10 '' separation on bright objects, orders of magnitude away from its exoplanet requirement of 50 μ'' ~ 20 μ'' on objects as faint as 11 mag ~ 13 mag in K band. This contribution focuses on upgrades and characterizations carried out since then. The astrometric metrology was extended from the Coudé focus of the Auxillary Telescopes to their secondary mirror, in order to reduce the baseline instabilities and improve the astrometric performance. While carrying out this extension, it was realized that the polarization retardance of the star separator derotator had a major impact on both the astrometric metrology and the fringe sensors. A local compensation of this retardance and the operation on a symmetric baseline allowed a new astrometric commissioning. In October 2013, an improved astrometric performance of 160 μ'' was demonstrated, still short of the requirements. Instabilities in the astrometric baseline still appear to be the dominating factor. In preparation to a review held in January 2014, a plan was developed to further improve the astrometric and faint target performance of PRIMA Astrometry. On the astrometric aspect, it involved the extension of the internal longitudinal metrology to primary space, the design and implementation of an external baseline metrology, and the development of an astrometric internal fringes mode. On the faint target aspect, investigations of the performance of the fringe sensor units and the development of an AO system (NAOMI) were in the plan. Following this review, ESO decided to take a proposal to the April 2014 STC that PRIMA be cancelled, and that ESO resources be concentrated on ensuring that Gravity and Matisse are a success. This proposal was recommended by the STC in May 2014, and endorsed by ESO.
description: 12 pages, 9 figures, 2 tables, Proceeding of SPIE conference in Montreal
Effects of hot phonons and thermal stress in micro-Raman spectra of molybdenum disulphide
Creators: name: Sokalski, Peter
name: Han, Zherui
name: Fleming, Gabriella Coloyan
name: Smith, Brandon
name: Sullivan, Sean E.
name: Huang, Rui
name: Ruan, Xiulin
name: Shi, Li
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Micro-Raman spectroscopy has become an important tool in probing thermophysical behavior in emerging functional materials such as two-dimensional (2D) layered structures. Localized heating by the focused Raman excitation laser beam is expected to produce both stress and nonequilibrium temperature distributions in the material. Here we investigate the effects of hot optical phonons in the Raman spectra of molybdenum disulphide (MoS2) and distinguish them from those caused by thermally-induced compressive stress, which causes a Raman frequency blue shift in the focused Raman laser spot. With the stress effect accounted for in micro-Raman measurements, the degree of nonequilibrium between the hot optical phonons and the acoustic phonon bath is found to be much smaller than those observed in prior micro-Raman measurements of suspended graphene. The observation agrees with a first-principles based theoretical prediction of overpopulated zone-center optical phonons compared to other optical phonons in the Brillouin zone and acoustic phonons. The findings provide detailed insight into the energy relaxation processes in this emerging 2D transition metal dichalcogenide (TMD) electronic and optoelectronic material and clarify an important question in micro-Raman measurements of thermal transport in this and other 2D materials.
description: 19 pages. 4 figures
Performance of the polarization leakage correction in the PILOT data
Creators: name: Bernard, J-Ph.
name: Bernard, A.
name: Roussel, H.
name: Choubani, I.
name: Alina, D.
name: Aumont, J.
name: Hughes, A.
name: Ristorcelli, I.
name: Stever, S.
name: Sugiyama, T. Matsumura S.
name: Komatsu, K.
name: de Gasperis, G.
name: Ferriere, K.
name: Guillet, V.
name: Ysard, N.
name: Ade, P.
name: de Bernardis, P.
name: Bray, N.
name: Crane, B.
name: Dubois, J. P.
name: Griffin, M.
name: Hargrave, P.
name: Longval, Y.
name: Louvel, S.
name: Maffei, B.
name: Masi, S.
name: Mot, B.
name: Montel, J.
name: Pajot, F.
name: Perot, E.
name: Ponthieu, N.
name: Rodriguez, L.
name: Sauvage, V.
name: Savini, G.
name: Tucker, C.
name: Vacher, F.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The Polarized Instrument for Long-wavelength Observation of the Tenuous interstellar medium (PILOT) is a balloon-borne experiment that aims to measure the polarized emission of thermal dust at a wavelength of 240 um (1.2 THz). The PILOT experiment flew from Timmins, Ontario, Canada in 2015 and 2019 and from Alice Springs, Australia in April 2017. The in-flight performance of the instrument during the second flight was described in Mangilli et al. 2019. In this paper, we present data processing steps that were not presented in Mangilli et al. 2019 and that we have recently implemented to correct for several remaining instrumental effects. The additional data processing concerns corrections related to detector cross-talk and readout circuit memory effects, and leakage from total intensity to polarization. We illustrate the above effects and the performance of our corrections using data obtained during the third flight of PILOT, but the methods used to assess the impact of these effects on the final science-ready data, and our strategies for correcting them will be applied to all PILOT data. We show that the above corrections, and in particular that for the intensity to polarization leakage, which is most critical for accurate polarization measurements with PILOT, are accurate to better than 0.4 % as measured on Jupiter during flight#3.
Trust, But Verify: On the Importance of Chemical Structure Curation in Cheminformatics and QSAR Modeling Research
Creators: name: Fourches, Denis
name: Muratov, Eugene
name: Tropsha, Alexander
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Molecular modelers and cheminformaticians typically analyze experimental data generated by other scientists. Consequently, when it comes to data accuracy, cheminformaticians are always at the mercy of data providers who may inadvertently publish (partially) erroneous data. Thus, dataset curation is crucial for any cheminformatics analysis such as similarity searching, clustering, QSAR modeling, virtual screening, etc., especially nowadays when the availability of chemical datasets in public domain has skyrocketed in recent years. Despite the obvious importance of this preliminary step in the computational analysis of any dataset, there appears to be no commonly accepted guidance or set of procedures for chemical data curation. The main objective of this paper is to emphasize the need for a standardized chemical data curation strategy that should be followed at the onset of any molecular modeling investigation. Herein, we discuss several simple but important steps for cleaning chemical records in a database including the removal of a fraction of the data that cannot be appropriately handled by conventional cheminformatics techniques. Such steps include the removal of inorganic and organometallic compounds, counterions, salts and mixtures; structure validation; ring aromatization; normalization of specific chemotypes; curation of tautomeric forms; and the deletion of duplicates. To emphasize the importance of data curation as a mandatory step in data analysis, we discuss several case studies where chemical curation of the original “raw” database enabled the successful modeling study (specifically, QSAR analysis) or resulted in a significant improvement of model's prediction accuracy. We also demonstrate that in some cases rigorously developed QSAR models could be even used to correct erroneous biological data associated with chemical compounds. We believe that good practices for curation of chemical records outlined in this paper will be of value to all scientists working in the fields of molecular modeling, cheminformatics, and QSAR studies.
DARTSRepair: Core-failure-set Guided DARTS for Network Robustness to Common Corruptions
Creators: name: Ren, Xuhong
name: Chen, Jianlang
name: Juefei-Xu, Felix
name: Xue, Wanli
name: Guo, Qing
name: Ma, Lei
name: Zhao, Jianjun
name: Chen, Shengyong
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Network architecture search (NAS), in particular the differentiable architecture search (DARTS) method, has shown a great power to learn excellent model architectures on the specific dataset of interest. In contrast to using a fixed dataset, in this work, we focus on a different but important scenario for NAS: how to refine a deployed network's model architecture to enhance its robustness with the guidance of a few collected and misclassified examples that are degraded by some real-world unknown corruptions having a specific pattern (e.g., noise, blur, etc.). To this end, we first conduct an empirical study to validate that the model architectures can be definitely related to the corruption patterns. Surprisingly, by just adding a few corrupted and misclassified examples (e.g., $10^3$ examples) to the clean training dataset (e.g., $5.0 \times 10^4$ examples), we can refine the model architecture and enhance the robustness significantly. To make it more practical, the key problem, i.e., how to select the proper failure examples for the effective NAS guidance, should be carefully investigated. Then, we propose a novel core-failure-set guided DARTS that embeds a K-center-greedy algorithm for DARTS to select suitable corrupted failure examples to refine the model architecture. We use our method for DARTS-refined DNNs on the clean as well as 15 corruptions with the guidance of four specific real-world corruptions. Compared with the state-of-the-art NAS as well as data-augmentation-based enhancement methods, our final method can achieve higher accuracy on both corrupted datasets and the original clean dataset. On some of the corruption patterns, we can achieve as high as over 45% absolute accuracy improvements.
description: To appear in Pattern Recognition (PR)
Low coherency of wind induced seismic noise: Implications for gravitational wave detection
Creators: name: Satari, Hamid
name: Blair, Carl
name: Ju, Li
name: Saygin, Erdinc
name: Blair, David
name: Zhao, Chunnong
name: Lumley, David
name: Meyers, Patrick
Publisher: name: arXiv
Year: 2022
Subjects: subject: Geophysics (physics.geo-ph)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Seismic noise poses challenges for gravitational wave detection. Effective vibration isolation and methods to subtract unsheildable Newtonian Noise are examples. Seismic arrays offer one way to deal with these issues assuming seismic coherency. In this paper we find that wind induced seismic noise is incoherent and will dramatically reduce the projected low frequency sensitivity of future gravitational wave detectors. To quantify this, we measure the coherence length of wind induced seismic noise from 0.06--20~Hz in three distinct locations: close to a building, among tall trees and in shrubs. We show that wind induced seismic noise is ubiquitous and reduces the coherence lengths form several hundred meters to 2--40~m for 0.06--0.1~Hz, from $>$60~m to 3--16~m for 1.5--2.5~Hz and from $>$35~m to 1--16~m around 16.6 Hz frequency bands in the study area. This leads to significant loss of velocity and angular resolution of the array for primary microseism, 5 times worse Newtonian Noise cancellation by wiener filtering at 2~Hz, while it does not pose additional challenge for Newtonian Noise cancellation between 10--20~Hz.
description: 15 pages, 8 figures
Combined Application of Cheminformatics- and Physical Force Field-Based Scoring Functions Improves Binding Affinity Prediction for CSAR Data Sets
Creators: name: Liu, Shubin
name: Hsieh, Jui-Hua
name: Tropsha, Alexander
name: Yin, Shuangye
name: Sedykh, Alexander
name: Dokholyan, Nikolay V.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2011

description: The curated CSAR-NRC benchmark sets provide valuable opportunity for testing or comparing the performance of both existing and novel scoring functions. We apply two different scoring functions, both independently and in combination, to predict binding affinity of ligands in the CSAR-NRC datasets. One, reported here for the first time, employs multiple chemical-geometrical descriptors of the protein-ligand interface to develop Quantitative Structure – Binding Affinity Relationships (QSBAR) models; these models are then used to predict binding affinity of ligands in the external dataset. Second is a physical force field-based scoring function, MedusaScore. We show that both individual scoring functions achieve statistically significant prediction accuracies with the squared correlation coefficient (R2) between actual and predicted binding affinity of 0.44/0.53 (Set1/Set2) with QSBAR models and 0.34/0.47 (Set1/Set2) with MedusaScore. Importantly, we find that the combination of QSBAR models and MedusaScore into consensus scoring function affords higher prediction accuracy than any of the contributing methods achieving R2 of 0.45/0.58 (Set1/Set2). Furthermore, we identify several chemical features and non-covalent interactions that may be responsible for the inaccurate prediction of binding affinity for several ligands by the scoring functions employed in this study.
Testing Rotating Regular Metrics with EHT Results of Sgr A*
Creators: name: Walia, Rahul Kumar
name: Ghosh, Sushant G
name: Maharaj, Sunil D
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The Event Horizon Telescope (EHT) observation unveiled the first image of supermassive black hole Sgr A* showing a shadow of diameter $θ_{sh}= 48.7 \pm 7\,μ$as with fractional deviation from the Schwarzschild black hole shadow diameter $δ= -0.08^{+0.09}_{-0.09}~\text{(VLTI)},-0.04^{+0.09}_{-0.10}~\text{(Keck)}$. The Sgr A* shadow size is within $~10\%$ of the Kerr predictions, providing us with another tool to investigate the nature of strong-field gravity. We use the Sgr A* shadow observables to constrain metrics of four independent and well-motivated, parametrically different from Kerr spacetime, rotating regular spacetimes, and the corresponding no-horizon spacetimes. We present constraints on the deviation parameter $g$ of rotating regular black holes. The shadow angular diameter $θ_{sh}$ within $1 σ$ region, places bounds on the parameters $a$ and $g$. Together with EHT bounds on $θ_{sh}$ and $δ$ of Sgr A*, our analysis concludes that the three rotating regular black holes, viz., Bardeen Hayward, and Simpson-Visser black holes, and corresponding no-horizon spacetimes agree with the EHT results of Sgr A*. Thus, these three rotating regular spacetimes and Kerr black holes are indiscernible in some parameter space, and one can not rule out the possibility of the former being strong candidates for astrophysical black holes.
description: 21 pages, 16 figures and 1 table. Published in the Astrophysical Journal
Machine Learning Based Propagation Loss Module for Enabling Digital Twins of Wireless Networks in ns-3
Creators: name: Almeida, Eduardo Nuno
name: Rushad, Mohammed
name: Kota, Sumanth Reddy
name: Nambiar, Akshat
name: Harti, Hardik L.
name: Gupta, Chinmay
name: Waseem, Danish
name: Santos, Gonçalo
name: Fontes, Helder
name: Campos, Rui
name: Tahiliani, Mohit P.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences

description: The creation of digital twins of experimental testbeds allows the validation of novel wireless networking solutions and the evaluation of their performance in realistic conditions, without the cost, complexity and limited availability of experimental testbeds. Current trace-based simulation approaches for ns-3 enable the repetition and reproduction of the same exact conditions observed in past experiments. However, they are limited by the fact that the simulation setup must exactly match the original experimental setup, including the network topology, the mobility patterns and the number of network nodes. In this paper, we propose the Machine Learning based Propagation Loss (MLPL) module for ns-3. Based on network traces collected in an experimental testbed, the MLPL module estimates the propagation loss as the sum of a deterministic path loss and a stochastic fast-fading loss. The MLPL module is validated with unit tests. Moreover, we test the MLPL module with real network traces, and compare the results obtained with existing propagation loss models in ns-3 and real experimental results. The results obtained show that the MLPL module can accurately predict the propagation loss observed in a real environment and reproduce the experimental conditions of a given testbed, enabling the creation of digital twins of wireless network environments in ns-3.