cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The computational geometry of hydrology data in geographic information systems
Creators: name: McAllister, Michael
Publisher: name: University of British Columbia
Year: 2009

description: Computational geometry counts geographic information systems (GIS) among its application areas. GIS data sets are large and are related to the Earth's surface by geometric coordinates. These properties mesh with geometry algorithms and their asymptotic analyses. This dissertation investigates the geometry in a specialized set of GIS problems, namely finding river network centrelines and finding watershed boundaries. Our goal is to create robust and consistent algorithms that solve these problems efficiently. When finding river network centrelines, the main issue is the robustness of the algorithm. The medial axis is an excellent centreline for a river or lake, but few robust implementations exist. Moreover, the medial axis uses parabolic segments, which are harder to represent accurately than line segments. We approximate the medial axis with a piecewise-linear structure that we compute with a robust algorithm for point Voronoi diagrams. Our approximation provides estimates of river area and associates the points on the centreline with the nearest river bank points, much like the medial axis. In turn, we use this association to identify opposite points along river banks. When finding watershed boundaries on triangulated terrains, we focus on finding an algorithm that is consistent with the terrain. In previous work, Nelson et al. [66] locate regions that drain to a common location, but their solution can be disconnected in degenerate cases. We propose a vector algorithm whose watersheds are consistent with the assumption on how water flows on the terrain; the algorithm guarantees one polygon per watershed. Our algorithm finds the watershed boundaries for local minima in the terrain in O(n log n + k) worst-case time where n is the number of points that model the terrain and k is the complexity of the watershed boundaries. We apply our solutions for these GIS problems to data in the British Columbia TRIM (Terrain Resource Inventory Mapping) format. For river networks, we find centrelines for the Fraser River in British Columbia and for a subset of its tributaries. We link these centrelines into a single river network. We have used this network to model the migration of salmon. For watersheds, we identify the boundaries of watersheds in the mountains north of Vancouver, British Columbia and compare the boundaries with manually-digitized watersheds of the same region.
Euphemisms for Death
Creators: name: Espinoza, Braulio
name: Mixco, Mauricio J.
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2021
Subjects: subject: klb

description: See Kiliwa Texts: "When I have Donned My Crest of Stars" (University of Utah Press, 1983), p. 135 for transcription, segmentation, glossing, and translation of this story.
Telltale Traces of U(1) Fields in Noncommutative Standard Model Extensions
Creators: name: Jaeckel, Joerg
name: Khoze, Valentin V.
name: Ringwald, Andreas
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Restrictions imposed by gauge invariance in noncommutative spaces together with the effects of ultraviolet/infrared mixing lead to strong constraints on possible candidates for a noncommutative extension of the Standard Model. In this paper, we study a general class of 4-dimensional noncommutative models consistent with these restrictions. Specifically we consider models based upon a gauge theory with the gauge group U(N_1)\times U(N_2) \times ... \times U(N_m) coupled to matter fields transforming in the (anti)-fundamental, bi-fundamental and adjoint representations. Noncommutativity is introduced using the Weyl-Moyal star-product approach on a continuous space-time. We pay particular attention to overall trace-U(1) factors of the gauge group which are affected by the ultraviolet/infrared mixing. We show that, in general, these trace-U(1) gauge fields do not decouple sufficiently fast in the infrared, and lead to sizable Lorentz symmetry violating effects in the low-energy effective theory. Making these effects unobservable in the class of models we consider would require pushing the constraint on the noncommutativity mass scale far beyond the Planck mass (M_{NC}\gtrsim 10^{100} M_{P}) and severely limits the phenomenological prospects of such models.
description: 22 pages, 2 figures, updated version contains some clarifying remarks on the nature of the studied class of models, some typos corrected
Predictive Analysis of Diabetic Retinopathy with Transfer Learning
Creators: name: Labhsetwar, Shreyas Rajesh
name: Salvi, Raj Sunil
name: Kolte, Piyush Arvind
name: venkatesh, Veerasai Subramaniam
name: Baretto, Alistair Michael
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: With the prevalence of Diabetes, the Diabetes Mellitus Retinopathy (DR) is becoming a major health problem across the world. The long-term medical complications arising due to DR have a significant impact on the patient as well as the society, as the disease mostly affects individuals in their most productive years. Early detection and treatment can help reduce the extent of damage to the patients. The rise of Convolutional Neural Networks for predictive analysis in the medical field paves the way for a robust solution to DR detection. This paper studies the performance of several highly efficient and scalable CNN architectures for Diabetic Retinopathy Classification with the help of Transfer Learning. The research focuses on VGG16, Resnet50 V2 and EfficientNet B0 models. The classification performance is analyzed using several performance metrics including True Positive Rate, False Positive Rate, Accuracy, etc. Also, several performance graphs are plotted for visualizing the architecture performance including Confusion Matrix, ROC Curve, etc. The results indicate that Transfer Learning with ImageNet weights using VGG 16 model demonstrates the best classification performance with the best Accuracy of 95%. It is closely followed by ResNet50 V2 architecture with the best Accuracy of 93%. This paper shows that predictive analysis of DR from retinal images is achieved with Transfer Learning on Convolutional Neural Networks.
description: ICNTE
Time-aware Graph Neural Networks for Entity Alignment between Temporal Knowledge Graphs
Creators: name: Xu, Chengjin
name: Su, Fenglong
name: Lehmann, Jens
Publisher: name: arXiv
Year: 2022
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Entity alignment aims to identify equivalent entity pairs between different knowledge graphs (KGs). Recently, the availability of temporal KGs (TKGs) that contain time information created the need for reasoning over time in such TKGs. Existing embedding-based entity alignment approaches disregard time information that commonly exists in many large-scale KGs, leaving much room for improvement. In this paper, we focus on the task of aligning entity pairs between TKGs and propose a novel Time-aware Entity Alignment approach based on Graph Neural Networks (TEA-GNN). We embed entities, relations and timestamps of different KGs into a vector space and use GNNs to learn entity representations. To incorporate both relation and time information into the GNN structure of our model, we use a time-aware attention mechanism which assigns different weights to different nodes with orthogonal transformation matrices computed from embeddings of the relevant relations and timestamps in a neighborhood. Experimental results on multiple real-world TKG datasets show that our method significantly outperforms the state-of-the-art methods due to the inclusion of time information.
description: Accepted at EMNLP2021
Causality theory of spacetimes with continuous Lorentzian metrics revisited
Creators: name: García-Heveling, Leonardo
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: Differential Geometry (math.DG)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 53C50 (Primary) 83C75 (Secondary)

description: We consider the usual causal structure $(I^+,J^+)$ on a spacetime, and a number of alternatives based on Minguzzi's $D^+$ and Sorkin and Woolgar's $K^+$, in the case where the spacetime metric is continuous, but not necessarily smooth. We compare the different causal structures based on three key properties, namely the validity of the push-up lemma, the openness of chronological futures, and the existence of limit causal curves. Recall that if the spacetime metric is smooth, $(I^+,J^+)$ satisfies all three properties, but that in the continuous case, the push-up lemma fails. Among the proposed alternative causal structures, there is one that satisfies push-up and open futures, and one that has open futures and limit curves. Furthermore, we show that spacetimes with continuous metrics do not, in general, admit a causal structure satisfying all three properties at once.
description: Significant changes in v2: notation changed, references added, numbering of theorems shifted. 12 pages, 2 figures, 1 table
Evaluation of potential drugs against leishmaniasis targeting catalytic subunit of Leishmania donovani nuclear DNA primase using ligand based virtual screening, docking and molecular dynamics approaches
Creators: name: Bhowmik, Deep
name: Jagadeesan, Rahul
name: Rai, Praveen
name: Rajat Nandi
name: Kothandan Gugan
name: Diwakar Kumar
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Biophysics
subject: Biochemistry
subject: Medicine
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified

description: Leishmania donovani, causes leishmaniasis, a global health trouble with around 89 different countries and its population under its risk. Replication initiation events have been instrumental in regulating the DNA duplication and as the small subunit of L. donovani nuclear DNA primase (Ld-PriS) inherits the catalytic site, it plays a vital role in DNA replication. In this study we have aimed Ld-PriS for the first time as a prospective target for the application of drug against Leishmania parasite. 3-D structures of Ld-PriS were built and ligand-based virtual screening was performed using hybrid similarity recognition techniques. Ligands from the ZINC database were used for the screening purposes based on known DNA primase inhibitor Sphingosine as a query. Top 150 ligands were taken into consideration for molecular docking against the query protein (Ld-PriS) using PyRx and iGEMDOCK softwares. Top five compounds with the best docking score were selected for pharmacokinetic investigation and molecular dynamic simulation. These top five screened inhibitors showed very poor binding affinity toward the catalytic subunit of human primase indicating their safety toward the host normal replication mechanism. The top five compounds showed good pharmacokinetic profiles and ADMET predictions revealed good absorption, solubility, permeability, uniform distribution, proper metabolism, minimal toxicity and good bioavailability. Simulation studies upto 50 ns revealed the three leads ZINC000009219046, ZINC000025998119 and ZINC000004677901 bind with Ld-PriS throughout the simulation and there were no huge variations in their backbone suggesting that these three may play as potential lead compounds for developing new drug against leishmaniasis. Communicated by Ramaswamy H. Sarma
Parton Distribution Functions with Twisted Mass Fermions
Creators: name: Capitani, S.
name: Jansen, K.
name: Papinutto, M.
name: Shindler, A.
name: Urbach, C.
name: Wetzorke, I.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We present a first Wilson twisted mass fermion calculation of the matrix element between pion states of the twist-2 operator, which is related to the the lowest moment < x > of the valence quark parton distribution function in a pion. Using Wilson twisted mass fermions in the quenched approximation we demonstrate that < x > can be computed at small pseudoscalar meson masses down to values of order 250 MeV. We investigate the scaling behaviour of this physically important quantity by applying two definitions of the critical mass and observe a scaling compatible with the expected O(a^2) behaviour in both cases. A combined continuum extrapolation allows to obtain reliable results for < x > at very small pseudoscalar meson masses, which previously could not be explored by lattice QCD simulations.
description: 15 pages, 3 figures
The Agricultural Situation in the Western Hemisphere: Review of 1973 and Outlook for 1974
Creators: name: Latin American Program Area, Foreign Demand
name: Latin American Program Area, Foreign Demand
Publisher: name: Unknown
Year: 1974
Subjects: subject: Agricultural and Food Policy
subject: Crop Production/Industries
subject: International Relations/Trade
subject: Livestock Production/Industries
subject: Agricultural production
subject: agricultural trade
subject: Western Hemisphere
subject: Canada
subject: Mexico
subject: Caribbean
subject: Central America
subject: South America

description: Western Hemisphere agricultural production recovered in 1973 from adverse conditions of a year earlier. Agricultural trade continued up to record values due to advancing world prices, increased exports, and larger imports needed to fill deficits from 1972 food production in many Latin American countries. U.S. agricultural exports to Hemisphere countries increased from the 1972 record of $1.7 billion to $2.7 billion in 1973; but the outlook is for some decline in 1974.
Felmy, Karl Christian, Kretschmar, Georg, von Lilienfeld, Fairy, Roepke, Claus-Jürgen: Tausend Jahre Christentum in Rußland
Creators: name: Friedrich, Hans-Peter
Publisher: name: Ökumenische Rundschau
Year: 2025

description: Ökumenische Rundschau, Bd. 38 Nr. 3 (1989): Ökumenische Rundschau, Band 38, Heft 3
N=3 super-Schwarzian from OSp(3|2) invariants
Creators: name: Galajinsky, Anton
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: It was recently demonstrated that the N=0,1,2,4 super-Schwarzian derivatives can be constructed by applying the method of nonlinear realizations to the finite-dimensional (super)conformal groups SL(2,R), OSp(1|2), SU(1,1|1), and SU(1,1|2), respectively. In this work, a similar scheme is realised for OSp(3|2). It is shown that the N=3 case exhibits a surprisingly richer structure of invariants, the N=3 super-Schwarzian being a particular member. We suggest that the extra invariants may prove useful in building an N=3 supersymmetric extension of the Sachdev-Ye-Kitaev model.
description: V2: 10 pages, a typo fixed in the abstract and main text; the version to appear in PLB. arXiv admin note: text overlap with arXiv:2007.04015
Dynamics and transport properties of heavy fermions: theory
Creators: name: Logan, David E
name: Vidhyadhiraja, N S
Publisher: name: arXiv
Year: 2005
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The paramagnetic phase of heavy fermion systems is investigated, using a non-perturbative local moment approach to the asymmetric periodic Anderson model within the framework of dynamical mean field theory. The natural focus is on the strong coupling Kondo-lattice regime wherein single-particle spectra, scattering rates, dc transport and optics are found to exhibit w/w_L,T/w_L scaling in terms of a single underlying low-energy coherence scale w_L. Dynamics/transport on all relevant (w,T)-scales are encompassed, from the low-energy behaviour characteristic of the lattice coherent Fermi liquid, through incoherent effective single-impurity physics likewise found to arise in the universal scaling regime, to non-universal high-energy scales; and which description in turn enables viable quantitative comparison to experiment.
description: 27 pages, 12 figures
Line formation of He I D3 and He I 10830 Å in a small-scale reconnection event
Creators: name: Libbrecht, T.
name: Bjørgen, J. P.
name: Leenaarts, J.
name: Rodríguez, J. de la Cruz
name: Hansteen, V.
name: Joshi, J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Aims. We aim to explain line formation of He I D3 and He I 10830 Å in small-scale reconnection events. Methods. We make use of a simulated Ellerman bomb (EB), present in a Bifrost-generated radiative Magnetohydrodynamics (rMHD) snapshot. The resulting He I D3 and He I 10830 Å line intensities are synthesized in 3D using the non-LTE Multi3D code. We compare the synthetic helium spectra with observed SST/TRIPPEL raster scans of EBs in He I 10830 Å and He I D3. Results. Emission in He I D3 and He I 10830 Å is formed in a thin shell around the EB at a height of $\sim 0.8$ Mm while the He I D3 absorption is formed above the EB at $\sim 4$ Mm. The height at which the emission is formed corresponds to the lower boundary of the EB, where the temperature increases rapidly from $6\cdot 10^3$ K to $10^6$ K. The opacity in He I D3 and He I 10830 Å is generated via photoionization-recombination driven by EUV radiation that is locally generated in the EB at temperatures in the range of $2\cdot 10^4 - 2\cdot 10^6$ K and electron densities between $10^{11}$ and $10^{13}$ cm$^{-3}$. The synthetic emission signals are a result of coupling to local conditions in a thin shell around the EB, with temperatures between $7\cdot 10^3$ and $10^4$ K and electron densities ranging from $\sim 10^{12}$ to $10^{13}$ cm$^{-3}$. Hence, both strong non-LTE as well as thermal processes play a role in the formation of He I D3 and He I 10830 Å in the synthetic EB/UV burst that we studied. Conclusions. In conclusion, the synthetic He I D3 and He I 10830 Å emission signatures are an indicator of temperatures of at least $2\cdot 10^4$ K and in this case as high as $\sim 10^6$ K.
description: 12 pages, 13 figures, submitted to A&A
Rescuing a black hole in the large-$q$ coupled SYK model
Creators: name: Lensky, Yuri D.
name: Qi, Xiao-Liang
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: In this paper, we develop a general effective theory for two copies of the Sachdev-Ye-Kitaev (SYK) model with a time-dependent bilinear coupling. For a quantum quench problem with an initial state of the thermofield double state, we show how the evolution of the system is described by a complex reparametrization field with a classical Hamiltonian. We study correlation functions in this system and compare the large-$q$ theory with the bulk low energy effective theory. In particular, we study the special case of a ``rescued black hole'', which describes how a time-evolved thermofield double state can evolve to the ground state of a coupled SYK model by a carefully tuned time-dependent coupling. In the low energy region, there is a holographic dual interpretation, which is a geometry that crosses over from an eternal black hole to a global AdS$_2$ vacuum. This family of geometries allow us to access the bulk region that would be the black hole interior without the rescue process. By comparing the large-$q$ and low energy theory, we find that even in the low energy region the deviation from the low energy theory cannot be neglected if the rescue process starts late. This provides evidence that the low energy effective theory of the bulk fails near the inner horizon of the black hole. We note the possibility of a connection to a two-dimensional analog of the higher-dimensional black hole singularity.
description: 30 pages, 10 figures
Self-consistent microscopic derivation of Markovian master equations for open quadratic quantum systems
Creators: name: D'Abbruzzo, Antonio
name: Rossini, Davide
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We provide a rigorous construction of Markovian master equations for a wide class of quantum systems that encompass quadratic models of finite size, linearly coupled to an environment modeled by a set of independent thermal baths. Our theory can be applied for both fermionic and bosonic models in any number of physical dimensions, and does not require any particular spatial symmetry of the global system. We show that, for non-degenerate systems under a full secular approximation, the effective Lindblad operators are the normal modes of the system, with coupling constants that explicitly depend on the transformation matrices that diagonalize the Hamiltonian. Both the dynamics and the steady-state (guaranteed to be unique) properties can be obtained with a polynomial amount of resources in the system size. We also address the particle and energy current flowing through the system in a minimal two-bath scheme and find that they hold the structure of Landauer's formula, being thermodynamically consistent.
description: 17 pages, 2 figures. Final version
Tribimaximal Neutrino Mixing and a Relation Between Neutrino- and Charged Lepton-Mass Spectra
Creators: name: Koide, Yoshio
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Brannen has recently pointed out that the observed charged lepton masses satisfy the relation m_e +m_μ+m_τ= {2/3} (\sqrt{m_e}+\sqrt{m_μ}+\sqrt{m_τ})^2, while the observed neutrino masses satisfy the relation m_{ν1} +m_{ν2} +m_{ν3} = {2/3} (-\sqrt{m_{ν1}}+\sqrt{m_{ν2}}+\sqrt{m_{ν3}})^2. It is discussed what neutrino Yukawa interaction form is favorable if we take the fact pointed out by Brannen seriously.
description: 13 pages, presentation modified
BD18stars_plots.pptx
Creators: name: Cowley, Charles
Publisher: name: Zenodo
Year: 2021
Subjects: astronomy, astrophysics,galactic chemical evolution

description: Plots of the differential abundances of stars from Bedell, et al. ApJ, 865,68 (2018) vs Atomic number Z. The plots show two basic shapes: (1) a positive overall slope, and (2) a V-shape. The former is common for young stars, the latter common for stars older than the sun
description: {"references": ["Cowley, C. R., Y\\\"{u}ce, K., and Bord, D. J. Astron. Nachr. 2020, 341, 125"]}
Computer assisted 3d craniofacial reconstruction
Creators: name: Bullock, William David
Publisher: name: University of British Columbia
Year: 2009

description: This thesis describes a methodology for forensic craniofacial reconstruction, denned as the reproduction a subject's facial appearance from the skull and mandible for the purposes of identification. The focus of this work is on reproducing three dimensional facial shape from the shape of the skull and mandible of a subject. This task can be broken into two parts. First, a technique for determining soft tissue depth at any point on the skull and mandible surface is presented. Second, two complementary methods of producing three dimensional facial shape are presented: a method which generates a surface using the skull and mandible as a skeleton of an implicit surface and a method which produces a hierarchical B-spline surface fit to facial surface locations. Surface material properties and facial features can then be added and modified to these models before being rendered and distributed. Results of these processes are presented.
The Fitness Value of Information with Delayed Phenotype Switching: Optimal Performance with Imperfect Sensing
Creators: name: Moffett, Alexander S.
name: Wallbridge, Nigel
name: Plummer, Carrol
name: Eckford, Andrew W.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: FOS: Biological sciences

description: The ability of organisms to accurately sense their environment and respond accordingly is critical for evolutionary success. However, exactly how the sensory ability influences fitness is a topic of active research, while the necessity of a time delay between when unreliable environmental cues are sensed and when organisms can mount a response has yet to be explored at any length. Accounting for this delay in phenotype response in models of population growth, we find that a critical error probability can exist under certain environmental conditions: an organism with a sensory system with any error probability less than the critical value can achieve the same long-term growth rate as an organism with a perfect sensing system. We also observe a trade off between the evolutionary value of sensory information and robustness to error, mediated by the rate at which the phenotype distribution relaxes to steady-state. The existence of the critical error probability could have several important evolutionary consequences, primarily that sensory systems operating at the non-zero critical error probability may be evolutionarily optimal.
description: Accepted for publication in Physical Review E
Resveratrol Binding to Human Complement fragment 5a (hC5a) may Modulate the C5aR Signaling Axes.
Creators: name: Mishra, Richa
name: Aurosikha Das
name: Soumendra Rana
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Biophysics
subject: Biochemistry
subject: Microbiology
subject: FOS: Biological sciences
subject: Genetics
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Immunology
subject: FOS: Clinical medicine
subject: 69999 Biological Sciences not elsewhere classified
subject: Cancer
subject: Science Policy
subject: 111714 Mental Health
subject: FOS: Health sciences
subject: 110309 Infectious Diseases
subject: 60506 Virology

description: Resveratrol (RSV), the active pharmaceutical ingredient (API) found in several fruits, nuts and marketed nutraceuticals is one of the promiscuous phytoalexin known to promote good health. The health benefits of RSV could be due to its antioxidant activity or its direct interaction with target proteins, resulting modulation of several cells signalling and inflammatory pathways. Among many of its disease preventing activities, RSV has been shown to ameliorate inflammation by directly binding the COX-1 and COX-2 enzymes, the established targets of common non-steroidal anti-inflammatory drugs (NSAIDS). As a follow up to our recent study, we have now identified that RSV can also directly target hC5a, a pro-inflammatory glycoprotein of the complement system, whose upregulation has been linked to exacerbate the chronic inflammation induced diseases, by recruitment of C5a receptor (C5aR) expressed in both immune and non-immune cells. The data derived from the molecular dynamics, automated docking and binding free energy calculation as well as from the circular dichroism, and steady state fluorescence studies indicates that glycosylation of hC5a may not alter its structure significantly and further confirms that RSV strongly bind to the hC5a, which may be responsible for the anti-inflammatory activity demonstrated by RSV in hC5a-C5aR induced inflammatory pathways.
An Omen of Death (preceded by rambling)
Creators: name: Espinoza, Braulio
name: Mixco, Mauricio J.
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2021
Subjects: subject: klb

description: See Kiliwa Texts: "When I have Donned My Crest of Stars" (University of Utah Press, 1983), p. 130 for transcription, segmentation, glossing, and translation of this story.
Dust Destruction in the High-Velocity Shocks Driven by Supernovae in the Early Universe
Creators: name: Nozawa, Takaya
name: Kozasa, Takashi
name: Habe, Asao
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We investigate the destruction of dust grains by sputtering in the high-velocity interstellar shocks driven by supernovae (SNe) in the early universe to reveal the dependence of the time-scale of dust destruction on the gas density $n_{{\rm H}, 0}$ in the interstellar medium (ISM) as well as on the progenitor mass $M_{\rm pr}$ and explosion energy $E_{\rm 51}$ of SN. The sputtering yields for the combinations of dust and ion species of interest to us are evaluated by applying the so-called universal relation with a slight modification. The dynamics of dust grains and their destruction by sputtering in shock are calculated by taking into account the size distribution of each dust species, together with the time evolution of temperature and density of gas in spherically symmetric shocks. The results of calculations show that the efficiency of dust destruction depends not only on the sputtering yield but also on the initial size distribution of each grain species. The efficiency of dust destruction increases with increasing $E_{\rm 51}$ and/or increasing $n_{{\rm H}, 0}$, but is almost independent of $M_{\rm pr}$ as long as $E_{\rm 51}$ is the same. The mass of gas swept up by shock is the increasing function of $E_{\rm 51}$ and the decreasing function of $n_{{\rm H}, 0}$. Combining these results, we present the approximation formula for the time-scale of destruction for each grain species in the early universe as a function of $E_{\rm 51}$ and $n_{{\rm H}, 0}$. This formula is applicable for investigating the evolution of dust grains at the early epoch of the universe with the metallicity of $Z \la 10^{-3}$ $Z_\odot$. The effects of the cooling processes of gas on the destruction of dust are briefly discussed.
description: 49 pages including 7 tables and 25 figures, accepted for publication in ApJ
Learning to Approximate Functions Using Nb-doped SrTiO$_3$ Memristors
Creators: name: Tiotto, Thomas F.
name: Goossens, Anouk S.
name: Borst, Jelmer P.
name: Banerjee, Tamalika
name: Taatgen, Niels A.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Emerging Technologies (cs.ET)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Memristors have attracted interest as neuromorphic computation elements because they show promise in enabling efficient hardware implementations of artificial neurons and synapses. We performed measurements on interface-type memristors to validate their use in neuromorphic hardware. Specifically, we utilised Nb-doped SrTiO$_3$ memristors as synapses in a simulated neural network by arranging them into differential synaptic pairs, with the weight of the connection given by the difference in normalised conductance values between the two paired memristors. This network learned to represent functions through a training process based on a novel supervised learning algorithm, during which discrete voltage pulses were applied to one of the two memristors in each pair. To simulate the fact that both the initial state of the physical memristive devices and the impact of each voltage pulse are unknown we injected noise at each timestep. Nevertheless, discrete updates based on local knowledge were shown to result in robust learning performance. Using this class of memristive devices as the synaptic weight element in a spiking neural network yields, to our knowledge, one of the first models of this kind, capable of learning to be a universal function approximator, and strongly suggests the suitability of these memristors for usage in future computing platforms.
description: 19 pages, 6, figures, 2 tables. Corresponding authors are Thomas F. Tiotto, and Anouk S. Goossens. Code available at https://github.com/Tioz90/Learning-to-approximate-functions-using-niobium-doped-strontium-titanate-memristors
On the Construction of a Post-Quantum Blockchain for Smart City
Creators: name: Chen, Jiahui
name: Gan, Wensheng
name: Hu, Muchuang
name: Chen, Chien-Ming
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: Owing to some special characteristics and features, blockchain is a very useful technique that can securely organize diverse devices in a smart city. It finds wide applications, especially in distributed environments, where entities such as wireless sensors need to be certain of the authenticity of the server. As contemporary blockchain techniques that address post-quantum concerns have not been designed, in this study, we investigate a blockchain in the post-quantum setting and seek to discover how it can resist attacks from quantum computing. In addition, traditional proof of work (PoW)-based consensus protocols such as Bitcoin cannot supply memory mining, and the transaction capacity of each block in a blockchain is limited and needs to be expanded. Thus, a new post-quantum proof of work (post-quantum PoW) consensus algorithm for security and privacy of smart city applications is proposed. It can be used to not only protect a blockchain under a quantum computing attack compared to existing classical hash-based PoW algorithms but also to supply memory mining. Meanwhile, an identity-based post-quantum signature is embedded into a transaction process to construct lightweight transactions. Subsequently, we provide a detailed description on the execution of the post-quantum lightweight transaction in a blockchain. Overall, this work can help enrich the research on future post-quantum blockchain and support the construction or architecture of emerging blockchain-based smart cities.
description: Elsevier. 20 pages, 9 figures, 6 tables
Analyzing organophosphate pesticide-serum albumin binding interaction: a combined STD NMR and molecular docking study
Creators: name: Dahiya, Vandana
name: Bibin G. Anand
name: Karunakar Kar
name: Samanwita Pal
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Biophysics
subject: Biochemistry
subject: Space Science
subject: Medicine
subject: Molecular Biology
subject: Pharmacology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Immunology
subject: FOS: Clinical medicine

description: In Vitro analysis of the interaction of organophosphate pesticides (OP) with bovine serum albumin (BSA) is crucial to understand their potential effects at the molecular level. In this context, we have employed Saturation Transfer Difference (STD) NMR experiments in conjunction with molecular docking studies to unravel the binding interaction of the OP chlorpyrifos (CPF), diazinon (DZN) and parathion (PA) in solution. The relative STD (%) suggested the detailed epitope mapping of these OP with BSA while the concentration-dependent STD NMR studies were performed to obtain the complex dissociation constant (KD) of the OP-BSA complexes; KD=1.81 × 10−4 M, 1.30 × 10−3 M and 1.11 × 10−3 M for CPF, DZN and PA were extracted respectively. Similar binding modes were identified for all the three OP using STD site-marker experiment. ITC experiments were performed as a complementary method that revealed a high binding affinity of OP-BSA complexes through non-covalent interaction. Molecular docking confirmed the possible interacting chemical groups of OP-BSA complexes. These significant results furnish valuable information about the toxicity risk of OP to proteins. Communicated by Ramaswamy H. Sarma
The Imprint of Large Scale Structure on the Ultra-High-Energy Cosmic Ray Sky
Creators: name: Ding, Chen
name: Globus, Noemie
name: Farrar, Glennys R.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Ultra-high-energy cosmic rays (UHECRs) are atomic nuclei from space with vastly higher energies than any other particles ever observed. Their origin and chemical composition remain a mystery. As we show here, the large- and intermediate-angular-scale anisotropies observed by the Pierre Auger Observatory are a powerful tool for understanding the origin of UHECRs. Without specifying any particular production mechanism, but only postulating that the source distribution follows the matter distribution of the local Universe, a good accounting of the magnitude, direction and energy dependence of the dipole anisotropy at energies above $8 \times 10^{18}$ eV is obtained, after taking into account the impact of energy losses during propagation (the "GZK horizon"), diffusion in extragalactic magnetic field and deflections in the Galactic magnetic field (GMF). This is a major step toward the long-standing hope of using UHECR anisotropies to constrain UHECR composition and magnetic fields. The observed dipole anisotropy is incompatible with a pure proton composition in this scenario. With a more accurate treatment of energy losses, it should be possible to further constrain the cosmic-ray composition and properties of the extragalactic magnetic field, self-consistently improve the GMF model, and potentially expose individual UHECR sources.
description: Accepted by the Astrophysical Journal Letters
Spin equation and its solutions
Creators: name: Bagrov, V. G.
name: Gitman, D. M.
name: Baldiotti, M. C.
name: Levin, A. D.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The aim of the present article is to study in detail the so-called spin equation (SE) and present both the methods of generating new solution and a new set of exact solutions. We recall that the SE with a real external field can be treated as a reduction of the Pauli equation to the (0+1)-dimensional case. Two-level systems can be described by an SE with a particular form of the external field. In this article, we also consider associated equations that are equivalent or (in one way or another) related to the SE. We describe the general solution of the SE and solve the inverse problem for this equation. We construct the evolution operator for the SE and consider methods of generating new sets of exact solutions. Finally, we find a new set of exact solutions of the SE.
description: 29 pages
The dynamical influence of cooling in the envelope of prestellar and protostellar cores
Creators: name: Lesaffre, P.
name: Belloche, A.
name: Chieze, J. -P.
name: Andre, P.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We compute numerical simulations of spherical collapse triggered by a slow increase in external pressure. We compare isothermal models to models including cooling with a simple but self-consistent treatment of the coupling between gas, grains and radiation field temperatures. The hydrostatic equilibrium appears to hold past the marginally stable state, until the collapse proceeds. The last hydrostatic state before collapse has a lower central gas temperature in the centre due to the enhanced coupling between gas, grains and radiation field. This results in slightly lower pressure gradients in the bulk of the envelope which is hence slightly more extended than in the isothermal case. Due to the sensitivity of the collapse on these initial conditions, protostellar infall velocities in the envelope turn out to be much slower in the case with cooling.Our models also compute the radiative transfer and a rather large chemical network coupled to gas dynamics. However, we note that the steady-state chemisorption of CO is sufficient to provide an accurate cooling function of the gas. This justifies the use of post-processing techniques to account for the abundance of observed molecules. Existing observations of infall signatures put very stringent constraints on the kinematics and temperature profile of the class 0 protostar IRAM 04191+1522. We show that isothermal models fail to account for the innermost slow infall motions observed, even with the most hydrostatic initial conditions. In contrast, models with cooling reproduce the general shape of the temperature profile inferred from observations and are in much better agreement with the infall signatures in the inner 3000 AU.
description: 12 pages, 9 figures, A&A accepted
Mountain Harvests
Creators: name: Ochurte, Rufino
name: Mixco, Mauricio J.
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2021
Subjects: subject: klb

description: See Kiliwa Texts: "When I have Donned My Crest of Stars" (University of Utah Press, 1983), p. 190 for transcription, segmentation, glossing, and translation of this story.
Line Identification and Excitation of Autoionizing States in a Late-Type, Low Mass Wolf-Rayet Star
Creators: name: Williams, Robert
name: Manea, Catherine
name: Margon, Bruce
name: Morrell, Nidia
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Identifications of a large fraction of previously unidentified lines in the complex spectrum of the low mass, late-type LMC [WC11] star J060819.93-715737.4 have been made utilizing electronic databases. There are an exceptionally large number of C II emission lines originating from autoionizing (ai) levels. Resonance fluorescence between the C II ground state and excited ai levels is shown to be a important photoabsorption process that is competitive with dielectronic recombination in exciting ai emission lines in stellar winds, and has broad application to many types of emission-line stars. In addition, numerous C II quartet multiplets appear in emission that are not excited directly by recombination or resonance fluorescence, signifying high wind densities in the emission region that enhance collisional transfer between doublet and quartet states.
description: 17 pages, 1 figure, 1 table. Accepted for publication in ApJ
Observations of Binary and Single Wolf-Rayet Stars with XMM-Newton and Chandra
Creators: name: Skinner, S.
name: Guedel, M.
name: Schmutz, W.
name: Zhekov, S.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present an overview of recent X-ray observations of Wolf-Rayet (WR) stars with XMM-Newton and Chandra. A new XMM spectrum of the nearby WN8 + OB binary WR 147 shows hard absorbed X-ray emission, including the Fe K-alpha line complex, characteristic of colliding wind shock sources. In contrast, sensitive observations of four of the closest known single WC (carbon-rich) WR stars have yielded only non-detections. These results tentatively suggest that single WC stars are X-ray quiet. The presence of a companion may thus be an essential factor in elevating the X-ray emission of WC + OB stars to detectable levels.
description: To appear in conf. proceedings: Close Binaries in the 21st Century - New Opportunities and Challenges, eds. A. Gimenez, E. Guinan, P. Niarchos, S. Rucinski; Astrophys. and Space Sci. (special issue), 2006. 4 pages, 2 figures
Evaluation of potential drugs against leishmaniasis targeting catalytic subunit of Leishmania donovani nuclear DNA primase using ligand based virtual screening, docking and molecular dynamics approaches
Creators: name: Bhowmik, Deep
name: Jagadeesan, Rahul
name: Rai, Praveen
name: Rajat Nandi
name: Kothandan Gugan
name: Diwakar Kumar
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Biophysics
subject: Biochemistry
subject: Medicine
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified

description: Leishmania donovani, causes leishmaniasis, a global health trouble with around 89 different countries and its population under its risk. Replication initiation events have been instrumental in regulating the DNA duplication and as the small subunit of L. donovani nuclear DNA primase (Ld-PriS) inherits the catalytic site, it plays a vital role in DNA replication. In this study we have aimed Ld-PriS for the first time as a prospective target for the application of drug against Leishmania parasite. 3-D structures of Ld-PriS were built and ligand-based virtual screening was performed using hybrid similarity recognition techniques. Ligands from the ZINC database were used for the screening purposes based on known DNA primase inhibitor Sphingosine as a query. Top 150 ligands were taken into consideration for molecular docking against the query protein (Ld-PriS) using PyRx and iGEMDOCK softwares. Top five compounds with the best docking score were selected for pharmacokinetic investigation and molecular dynamic simulation. These top five screened inhibitors showed very poor binding affinity towards the catalytic subunit of human primase indicating their safety towards the host normal replication mechanism. The top five compounds showed good pharmacokinetic profiles and ADMET predictions revealed good absorption, solubility, permeability, uniform distribution, proper metabolism, minimal toxicity and good bioavailability. Simulation studies upto 50 ns revealed the three leads ZINC000009219046, ZINC000025998119 and ZINC000004677901 bind with Ld-PriS throughout the simulation and there were no huge variations in their backbone suggesting that these three may play as potential lead compounds for developing new drug against leishmaniasis.
Iterative Power Algorithm for Global Optimization with Quantics Tensor Trains
Creators: name: Soley, Micheline B.
name: Bergold, Paul
name: Batista, Victor S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Optimization algorithms play a central role in chemistry since optimization is the computational keystone of most molecular and electronic structure calculations. Herein, we introduce the iterative power algorithm (IPA) for global optimization and a formal proof of convergence for both discrete and continuous global search problems, which is essential for applications in chemistry such as molecular geometry optimization. IPA implements the power iteration method in quantics tensor train (QTT) representations. Analogous to the imaginary time propagation method with infinite mass, IPA starts with an initial probability distribution and iteratively applies the recurrence relation $ρ_{k+1}({\bf x})=U({\bf x})ρ_k({\bf x})/\|Uρ_k\|_{L^1}$, where $U({\bf x})=e^{-V({\bf x})}$ is defined in terms of the potential energy surface (PES) $V({\bf x})$. Upon convergence, the probability distribution becomes a delta function, so the global minimum can be obtained as the position expectation value. QTT representations are generated by fast adaptive interpolation of multidimensional arrays to bypass the curse of dimensionality and the need to evaluate $V({\bf x})$ for all possible ${\bf x}$. We illustrate the capabilities of IPA for global search optimization of two multidimensional PESs, including a differentiable model PES of a DNA chain and a discrete non-differentiable PES, $V(p)=\text{mod}(N,p)$, that resolves the prime factors of an integer $N$, with $p$ in the space of prime numbers folded as a $d$-dimensional $2_1 \times 2_2 \times \cdots \times 2_d$ tensor. We find that IPA resolves multiple degenerate global minima even when separated by large energy barriers in the highly rugged landscape of the potentials. Therefore, IPA should be of great interest for a wide range of other optimization problems ubiquitous in molecular and electronic structure calculations.