cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Il cerchio che non chiude: forme della temporalità nella poesia contemporanea
Creators: name: Giusti, Francesco
Publisher: name: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo
Year: 2018

description: Riprendendo le riflessioni sulle differenti modalità con cui poesie di epoche diverse marcano la loro conclusione indagate da Barbara Herrnstein Smith in Poetic Closure: A Study of How Poems End (1968), sulla circolarità che il testo lirico innesca nell’atto di lettura proposta da Timothy Bahti in Ends of the Lyric: Direction and Consequence in Western Poetry (1996) e sul carattere queer che l’incompiutezza può assumere rivendicato in Queer Lyrics: Difficulty and Closure in American Poetry (2002) di John Emil Vincent, l’articolo vuole indagare, attraverso Wallace Stevens, Eugenio Montale, Louise Glück e John Ashbery, in che modo la poesia contemporanea si faccia carico dell’incompiutezza. L’ipotesi è che, se per secoli questa incompiutezza è stata anche un grande tema della poesia – si pensi soltanto all’incongruenza tra la chiusura formale del testo della poesia medievale e rinascimentale e la ribadita impossibilità di una perfetta rappresentazione dell’oggetto d’amore – dal Modernismo in poi la lirica non rinunci a intraprendere il suo percorso, ma assuma consapevolmente su di sé l’errore facendone il principio strutturante del proprio discorso. Il cerchio che non chiude diventa allora una forma specifica della temporalità per la lirica (e per il lettore) che non insegue il successo del percorso lineare, ma accoglie l’errore insito nel suo sforzo per accettare di praticare un’approssimazione infinita e per maturare coscienza della propria pratica. La non compiutezza della poesia, infine, potrebbe essere proprio quel che assicura la ripetibilità del testo. Partendo dal valore centrale che l’iteratività formale della lirica assume nel recente Theory of the Lyric (2015) di Jonathan Culler, nell’ultima parte l’articolo costruisce un’ipotesi sulle ragioni per cui proprio il fatto che la poesia, come artefatto, debba concludersi senza necessariamente compiersi interamente consente al testo lirico di presentarsi come performance ripetibile attraverso i secoli e rinnovabile a ogni atto di lettura.
description: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo, N. 1 (2017)
I nuovi linguaggi teatrali in Spagna e l’indagine sulla contemporaneità
Creators: name: Fox, Manuela
Publisher: name: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo
Year: 2018

description: Il teatro, da sempre efficace strumento di indagine sulla realtà contingente in cui viene prodotto, sta vivendo in Spagna un periodo di particolare vivacità, dettato dal fatto che molti drammaturghi hanno scelto di portare sulle scene gli eventi epocali che stanno segnando l’inizio del XXI secolo. Il terrorismo, le guerre di religione, le ondate migratorie, l’instabile situazione politica sono quindi diventati i protagonisti indiscussi dei palcoscenici spagnoli. Il potenziale politico del teatro viene così sfruttato appieno con risultati che non possono non toccare nel profondo anche la struttura testuale. È innegabile infatti che quest’ondata di opere che affrontano temi di attualità stia significativamente modificando il linguaggio e le tecniche teatrali. Di fronte al clima di incertezza, di paura, di dubbio, quali risposte può dare il teatro? E come vengono formulate in termini non solo tematici ma anche testuali e performativi? Attraverso testi di Angélica Liddell, Juan Mayorga e altri autori drammatici ultimamente molto presenti sui palcoscenici non solo spagnoli ma anche italiani, si cercherà di dare risposta a questi quesiti.
description: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo, N. 1 (2017)
Extraction of P11 Resonance from pi-N Data and Its Stability
Creators: name: Nakamura, S. X.
name: Kamano, H.
name: Lee, T. -S. H.
name: Sato, T.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: An important question about resonance extraction is how much resonance poles and residues extracted from data depend on a model used for the extraction, and on the precision of data. We address this question with the dynamical coupled-channel (DCC) model developed in Excited Baryon Analysis Center (EBAC) at JLab. We focus on the P11 pi-N scattering. We examine the model-dependence of the poles by varying parameters to a large extent within the EBAC-DCC model. We find that two poles associated with the Roper resonance are fairly stable against the variation. We also develop a model with a bare nucleon, thereby examining the stability of the Roper poles against different analytic structure of the P11 amplitude below pi-N threshold. We again find a good stability of the Roper poles.
description: 6 pages, 8 figures, Contribution to the proceedings of 24th International Nuclear Physics Conference (INPC), Vancouver, Canada, 4-9 July 2010
Alfa e omega. Il senso della fine nella letteratura e nel cinema tedeschi dopo il 1945
Creators: name: Costagli, Simone
Publisher: name: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo
Year: 2018

description: Nella letteratura e nel cinema tedeschi immediatamente successivi al 1945, la fine di un testo o di un film diventa parte di un esercizio collettivo dove la questione della catarsi non è mai innocente, ma aggravata dal peso di una colpa che va oltre alla richiesta di perdono. L’articolo prende le mosse da uno dei testi che trattano il motivo della fine in modo più programmatico: il Doctor Faustus di Thomas Mann, scritto tra gli anni della Guerra e quelli immediatamente successivi, è un romanzo che tratta i temi dell’apocalissi e della fine soprattutto anche attraverso la descrizione delle opere musicali del suo protagonista Adrian Leverkühn, in particolare due tra le ultime: Apocalipsis cum figuris e Lamentatio Doctoris Fausti. Apparentemente, non potrebbe esserci forse distanza maggiore che tra questa opera tarda del grande romanziere tedesco e la cinematografia tedesca immediatamente successiva alla fine del nazionalsocialismo. Eppure, quest’ultima può fornire esempi di un’altra modalità attraverso cui leggere il ‘senso della fine’ in Germania. Riorganizzata dagli alleati a Ovest come semplice mezzo di intrattenimento oppure come veicolo per imporre valori delle democrazie occidentali, la cinematografia della Germania Ovest mostra in questi anni, in alcuni casi, strategie non banali per rielaborare la fine all’interno della dimensione spettacolare e collettiva del film. Il genere principe è il melodramma, come avviene del resto nella cinematografia internazionale di quegli anni. Pur obbedendo alle regole che questo genere impone, il melodramma cinematografico può dare interpretazioni diverse del trauma della fine: secondo una modalità diretta e realistica, come ad esempio in In quei giorni (1947) di Helmut Käutner oppure attraverso filtri psicoanalitici, come ne La peccatrice (1951) di Willy Forst.
description: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo, N. 1 (2017)
Impossibile chiusura: il romanzo moltiplicato
Creators: name: Bertoni, Federico
Publisher: name: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo
Year: 2018

description: “Nella relazione fondamentale con se stessi”, scrive Robert Musil in una pagina famosa dell’Uomo senza qualità, “quasi tutti gli uomini sono dei narratori. A loro piace la serie ordinata dei fatti perché somiglia a una necessità, e grazie all’impressione che la vita abbia un ‘corso’ si sentono in qualche modo protetti in mezzo al caos”. Ci sono però fasi della storia culturale in cui gli esseri umani sembrano perdere il filo del racconto, e con esso ogni possibilità di ricondurre il caos del reale a un sensato ‘ordine narrativo’. La grande letteratura del Novecento ha dato corpo a questa inquietudine: ne ha fatto spesso un’ossessione, in un tentativo caparbio – destinato inevitabilmente allo scacco – di tradurre in forma narrativa quella “coscienza della complessità” di cui parla Carlo Emilio Gadda, cioè la percezione di una realtà sempre più stratificata, molteplice e inesauribile. Paradossi teorici, invenzioni strutturali e opzioni stilistiche hanno portato quindi vari scrittori a ‘moltiplicare’ il romanzo, per riprodurre, nel perimetro chiuso sella pagina scritta, la molteplicità brulicante e inafferrabile del mondo reale (o delle sue infinite controfigure fittizie). Strutture talvolta caotiche, accumulative, stratificate, talaltra improntate a raffinatissime geometrie strutturali che sono destinate tuttavia a rimanere fatalmente aperte, a celare punti difettosi, pezzi mancanti, vuoti metafisici al centro del sistema. Se la realtà non chiude, anche il romanzo è condannato a una ‘impossibile chiusura’.
description: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo, N. 1 (2017)
Existence of isoperimetric regions in contact sub-Riemannian manifolds
Creators: name: Galli, Matteo
name: Ritoré, Manuel
Publisher: name: arXiv
Year: 2010
Subjects: subject: Differential Geometry (math.DG)
subject: Metric Geometry (math.MG)
subject: FOS: Mathematics

description: We prove existence of regions minimizing perimeter under a volume constraint in contact sub-Riemannian manifolds such that their quotient by the group of contact transformations preserving the sub-Riemannian metric is compact.
description: 24 pages, no figures
The horizon problem for prevalent surfaces
Creators: name: Falconer, Kenneth J.
name: Fraser, Jonathan M.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Metric Geometry (math.MG)
subject: FOS: Mathematics
subject: 28A80

description: We investigate the box dimensions of the horizon of a fractal surface defined by a function $f \in C[0,1]^2 $. In particular we show that a prevalent surface satisfies the `horizon property', namely that the box dimension of the horizon is one less than that of the surface. Since a prevalent surface has box dimension 3, this does not give us any information about the horizon of surfaces of dimension strictly less than 3. To examine this situation we introduce spaces of functions with surfaces of upper box dimension at most α, for α$\in$ [2,3). In this setting the behaviour of the horizon is more subtle. We construct a prevalent subset of these spaces where the lower box dimension of the horizon lies between the dimension of the surface minus one and 2. We show that in the sense of prevalence these bounds are as tight as possible if the spaces are defined purely in terms of dimension. However, if we work in Lipschitz spaces, the horizon property does indeed hold for prevalent functions. Along the way, we obtain a range of properties of box dimensions of sums of functions.
Regulating the last mile : paratransit in Delhi
Creators: name: Harding, Simon
Publisher: name: University of British Columbia
Year: 2017

description: Paratransit plays a vital role in cities in the Global South, including India. Paratransit modes - those which lack a fixed route and timetable - perform trips impractical or impossible on mass transit and, in Delhi, increasingly provide feeder services to the city’s metro rail and Bus Rapid Transit (BRT) systems. Despite their critical role in the urban transit ecosystem in Indian cities, paratransit operators have a poor reputation amongst the middle-classes and the English-language media for overcharging passengers and flouting regulations. In response, the current policy approach to paratransit regulation is marked by judicial and technical interventions. These are seldom empirically driven, and often represent a relative neglect of the paratransit sector. This study aims to correct this neglect by providing a detailed empirical account of paratransit operations and the regulatory environment in Delhi. It makes the case that paratransit is a vital last mile mode, and that evidence based regulation of paratransit modes is critical to improving public transport in Indian cities. This study does this by analyzing existing paratransit regulation and demonstrating that the current approach involves a heavy burden of compliance that inflates costs for operators. It then presents an empirical analysis of the economics of operating an auto-rickshaw using a survey of drivers (n=301). It finds that overcharging may be explained by the structure of operators’ costs and revenues. A survey of passengers (n=689) provides data for a series of statistical models, which suggests that the incidence and magnitude of overcharging are explained by the economics of auto-rickshaw trip making and associated with such variables as trip distance and the location of the destination. It then seeks to explain the rise of battery-rickshaws as a mode paratransit in the city and the lessons provided by their sudden proliferation. A fieldwork survey of drivers (n=302) provides data on their role and operating economics. A passenger survey (n=540) finds battery-rickshaws are largely replacing cycle-rickshaws. This case study sheds light on the environment in which urban transportation policy decisions are made. The study concludes by presenting some policy recommendations for paratransit in Delhi.
On the required mass for exoplanetary radio emission
Creators: name: Grießmeier, Jean-Mathias
name: Erkaev, N. V.
name: Weber, C.
name: Lammer, H.
name: Ivanov, V. A.
name: Odert, P.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The detection of radio emission from an exoplanet would constitute the best way to determine its magnetic field. Indeed, the presence of a planetary magnetic field is a necessary condition for radio emission via the Cyclotron Maser Instability. The presence of a magnetic field is, however, not sufficient. At the emission site, the local cyclotron frequency has to be sufficiently high compared to the local plasma frequency. As strong stellar insolation on a low-mass planet can lead to an extended planetary atmosphere, the magnetospheric plasma frequency depends on the planetary mass, its orbital distance, and its host star. We show that an extended planetary atmosphere can quench the radio emission. This seems to be true, in particular, for an important fraction of the planets less massive than approximately two Jupiter masses and with orbital distances below $\sim$0.2 AU. Most of the best candidates suggested by radio scaling laws lie in this parameter space. Taking this effect quenching into account will have important implications for the target selection of observation campaigns. At the same time, this effect will have consequences for the interpretation of observational data.
description: 6 pages, 1 figure. Proceedings of Planetary, Solar and Heliospheric Radio Emissions IX (2023)
Massive star formation in Wolf-Rayet galaxies. V: Star formation rates, masses and the importance of galaxy interactions
Creators: name: Lopez-Sanchez, Angel R.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: (Abridged) We have performed a comprehensive analysis of a sample of 20 starburst galaxies, most of them classified as Wolf-Rayet galaxies. In this paper, the last of the series, we analyze the global properties of our galaxy sample using multiwavelength data (X-ray, FUV, optical, NIR, FIR, and radio). The agreement between our Ha-based SFR and those provided by indicators at other wavelengths is remarkable, but we consider that the new Ha-based calibration provided by Calzetti et al. (2007) should be preferred over older calibrations. The FUV-based SFR provides a powerful tool to analyze the star-formation activity in both global and local scales independently to the Ha emission. We provide empirical relationships between the ionized gas mass, neutral gas mass, dust mass, stellar mass, and dynamical mass with the B-luminosity. Although all mass estimations increase with increasing luminosity, we find important deviations to the general trend in some objects, that seem to be consequence of their particular evolutionary histories. We investigate the mass-metallicity relations and conclude that both the nature and the star-formation history are needed to understand the relationships between both properties. The majority of the galaxies follow a Schmidt-Kennicutt scaling law of star-formation that agrees with that reported in individual star-forming regions within M~51 but not with that found in normal spiral galaxies. We found a relation between the reddening coefficient and the warm dust mass indicating that the extinction is mainly internal to the galaxies. Considering all data, we found that 17 up to 20 galaxies are clearly interacting or merging with low-luminosity dwarf objects or HI clouds. We conclude that interactions do play a fundamental role in the triggering mechanism of the strong star-formation activity observed in dwarf starburst galaxies.
description: 33 pages, 21 figures, accepted for publication by A&A
The Cost Function of a Two-Level Inventory System with identical retailers benefitting from Information Sharing
Creators: name: Sedigh, Amir Hosein Afshar
name: Haji, Rasoul
name: Sajadifar, Seyed Mehdi
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Economics (econ.GN)
subject: FOS: Economics and business

description: This paper investigates a two-echelon inventory system with a central warehouse and N (N > 2) retailers managed by a centralized information-sharing mechanism. In particular, the paper mathematically models an easy-to-implement inventory control system that facilitates making use of information. Some assumptions of the paper include: a) constant delivery time for retailers and the central warehouse and b) Poisson demand with identical rates for retailers. The inventory policy comprises continuous review (R,Q)-policy on the part of retailers and triggering the system with m batches (of a given size Q) at the central warehouse. Besides, the central warehouse monitors retailers' inventory and may order batches sooner than retailers' reorder point, when their inventory position reaches R + s. An earlier study proposed the policy and its cost function approximation. This paper derives an exact mathematical model of the cost function for the aforementioned problem.
Antibacterial activity of prenylated benzopyrans from Peperomia obtusifolia (Piperaceae)
Creators: name: Mostacero, Nathalie Ruiz
name: Castelli, María Victoria
name: Cutró, Andrea Carla
name: Hollmann, Axel
name: Batista, João Marcos
name: Furlan, Maysa
name: Valles, Julieta
name: Fulgueira, Cecilia Luisa
name: López, Silvia Noelí
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biochemistry
subject: Microbiology
subject: FOS: Biological sciences
subject: Cell Biology
subject: Pharmacology
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Cancer
subject: Hematology
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: 60506 Virology

description: Peperomia obtusifolia is a herbaceous perennial plant native to the Americas reported as a traditional medicine to treat snake bites and as a skin cleanser. The bioassay-guided fractionation of crude extracts from aerial parts of P. obtusifolia against a panel of clinically important fungi and bacteria, showed that hexane and dichloromethane extracts demonstrated selective bacterial inhibition, allowing the isolation of the known compounds peperobtusin A (1), and 3,4-dihydro-5-hydroxy-2,7-dimethyl-8-(3”-methyl-2”-butenyl)-2-(4’-methyl-1’,3’-pentadienyl)-2H-1-benzopyran-6-carboxylic acid (2) from dichloromethane extract. Compound 2 was active against Gram-positive bacteria including community acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) isolates and an Enterococcus faecalis vancomycin-resistant strain, with minimal inhibitory concentration (MIC) values of 4 μg/mL (10.8 μM) and 8 μg/mL (21.6 μM) respectively. The interaction of compound 2 with the bacterial membrane was demonstrated by means of Zeta potential experiments on S. aureus, then confirming the membrane damage by fluorescent microscopy experiments.
Optimal Strouhal number for swimming animals
Creators: name: Eloy, Christophe
Publisher: name: arXiv
Year: 2011
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: To evaluate the swimming performances of aquatic animals, an important dimensionless quantity is the Strouhal number, St = fA/U, with f the tail-beat frequency, A the peak-to-peak tail amplitude, and U the swimming velocity. Experiments with flapping foils have exhibited maximum propulsive efficiency in the interval 0.25 < St < 0.35 and it has been argued that animals likely evolved to swim in the same narrow interval. Using Lighthill's elongated-body theory to address undulatory propulsion, it is demonstrated here that the optimal Strouhal number increases from 0.15 to 0.8 for animals spanning from the largest cetaceans to the smallest tadpoles. To assess the validity of this model, the swimming kinematics of 53 different species of aquatic animals have been compiled from the literature and it shows that their Strouhal numbers are consistently near the predicted optimum.
description: 21 pages, 6 figures
Adaptive Dependency Learning Graph Neural Networks
Creators: name: Sriramulu, Abishek
name: Fourrier, Nicolas
name: Bergmeir, Christoph
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Graph Neural Networks (GNN) have recently gained popularity in the forecasting domain due to their ability to model complex spatial and temporal patterns in tasks such as traffic forecasting and region-based demand forecasting. Most of these methods require a predefined graph as input, whereas in real-life multivariate time series problems, a well-predefined dependency graph rarely exists. This requirement makes it harder for GNNs to be utilised widely for multivariate forecasting problems in other domains such as retail or energy. In this paper, we propose a hybrid approach combining neural networks and statistical structure learning models to self-learn the dependencies and construct a dynamically changing dependency graph from multivariate data aiming to enable the use of GNNs for multivariate forecasting even when a well-defined graph does not exist. The statistical structure modeling in conjunction with neural networks provides a well-principled and efficient approach by bringing in causal semantics to determine dependencies among the series. Finally, we demonstrate significantly improved performance using our proposed approach on real-world benchmark datasets without a pre-defined dependency graph.
The Significant Digit Law in Statistical Physics
Creators: name: Shao, Lijing
name: Ma, Bo-Qiang
Publisher: name: arXiv
Year: 2010
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The occurrence of the nonzero leftmost digit, i.e., 1, 2, ..., 9, of numbers from many real world sources is not uniformly distributed as one might naively expect, but instead, the nature favors smaller ones according to a logarithmic distribution, named Benford's law. We investigate three kinds of widely used physical statistics, i.e., the Boltzmann-Gibbs (BG) distribution, the Fermi-Dirac (FD) distribution, and the Bose-Einstein (BE) distribution, and find that the BG and FD distributions both fluctuate slightly in a periodic manner around the Benford distribution with respect to the temperature of the system, while the BE distribution conforms to it exactly whatever the temperature is. Thus the Benford's law seems to present a general pattern for physical statistics and might be even more fundamental and profound in nature. Furthermore, various elegant properties of Benford's law, especially the mantissa distribution of data sets, are discussed.
description: 21 latex pages, 5 figures, final version in journal publication
High-frequency pulsations in DFB-lasers with amplified feedback
Creators: name: Brox, Olaf
name: Bauer, Stefan
name: Radziunas, Mindaugas
name: Wolfrum, Matthias
name: Sieber, Jan
name: Kreissl, Jochen
name: Sartorius, Bernd
name: Wünsche, Hans-Jürgen
Publisher: name: Weierstrass Institute
Year: 2003
Subjects: subject: semiconductor laser
subject: optical feedback
subject: pulsations
subject: 42.65.Sf

description: We describe the basic ideas behind the concept of DFB-lasers with short optical feedback for the generation of high-frequency self-pulsations (SPs) and show the theoretical background describing realized devices. It is predicted by theory that the SP frequency increases with increasing feedback strength. To provide evidence for this we propose a novel device design which employs an amplifier section in the integrated feedback cavity of a DFB-laser. We present results from numerical simulations and experiments. It has been shown experimentally that a continuous tuning of the SP frequency from 12 to 45GHz can be adjusted via the control of the feedback strength. The numerical simulations which are in good accordance with experimental investigations give an explanation for a self stabilizing effect of the SPs due to the additional carrier dynamic in the integrated feedback cavity.
Neutron scattering study of a quasi-2D spin-1/2 dimer system Piperazinium Hexachlorodicuprate under hydrostatic pressure
Creators: name: Hong, Tao
name: Stock, C.
name: Cabrera, I.
name: Broholm, C.
name: Qiu, Y.
name: Leao, J. B.
name: Poulton, S. J.
name: Copley, J. R. D.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We report inelastic neutron scattering study of a quasi-two-dimensional S=1/2 dimer system Piperazinium Hexachlorodicuprate under hydrostatic pressure. The spin gap Δ becomes softened with the increase of the hydrostatic pressure up to P= 9.0 kbar. The observed threefold degenerate triplet excitation at P= 6.0 kbar is consistent with the theoretical prediction and the bandwidth of the dispersion relation is unaffected within the experimental uncertainty. At P= 9.0 kbar the spin gap is reduced to 0.55 meV from 1.0 meV at ambient pressure.
description: 4 pages, 5 figures
Feynman's method in chiral nanorod-based metamaterial nanoplasmonics
Creators: name: Galiautdinov, Andrei
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: We propose a theoretical approach to some of the nanorod-based metamaterial implementations that does not depend on macroscopic electrodynamics. The approach is motivated by the fact that in actual experiments the incident electromagnetic wave encounters a metamaterial structure which is planar in its shape, contains a layer or two of artificially created building blocks, and therefore cannot be regarded as a three-dimensional continuous medium. This leads to a theoretical framework in which the phenomenological concept of refractive index loses its principled meaning, and the deeper concept of scattering is taking center stage. Our proposal and its mathematical realization rely heavily on Feynman's explanation of the physical origin of the index of refraction and on his formula for the field of a plane of oscillating charges. We provide a complete proof of Feynman's formula, filling in some steps that were missing in the original derivation, and then generalize it to the case of a finite disk, which may be relevant to the actual experiments involving laser beams. We then show how the formula can be applied to metamaterial nanoplasmonics by considering some subtle interference effects in narrow laser beams striking metamaterial plates. The first two effects use a single layer of aligned plasmonic nanorods, while the third uses a single layer of gyrotropic elements that may conveniently be described by the celebrated Born-Kuhn oscillator model. The considered effects can potentially be used in the development of quality standards for various metamaterial devices.
description: Pre-refereed version submitted to Physica Scripta. The version of record is available at the DOI provided below. 21 pages, 15 figures
Prediction of water distribution system pipes and isolation valves failure using Bayesian models with the consideration of soil corrosion and climate change
Creators: name: Demissie, Gizachew Ababu
Publisher: name: University of British Columbia
Year: 2017

description: Aging water distribution system pipes and valves are at stake due to progressive deterioration. Deterioration of the pipes and valves might be as a result of static, operational and dynamic (time-dependent) factors. The impact of these factors are manifested in the form of declined water quality, diminished hydraulic capacity, increased leakage rate and frequent pipe breaks. Reported literature shows that there are a limited number of comprehensive models which integrate characteristics of these factors. As a result, municipalities have been facing a challenge in predicting pipe failure and practicing proactive decision making. The primary objective of this research was to develop a comprehensive Bayesian (Bayesian Belief Network (BBN), Dynamic Bayesian Network (DBN) and Bayesian Model Averaging (BMA)) models to predict/forecast pipe and valve failures by considering driving factors with particular attention to soil corrosion and climate change. Firstly, a comprehensive BBN-based Soil Corrosivity Index (SCI) model was developed to account for interdependencies among different soil parameters. The developed BBN-SCI model combines in situ, experimental, and expert opinion data sources. This model is, then, extended to BBN-based Remaining Service Life (RSL) model which predicts pit depth and quanti es the probability and time to failure for cast iron pipes. The next part of this research evaluates the failure of valves using BBN-based failure mode and effect analysis. The DBN model considers static, operational and time-dependent factors to predict annual and monthly pipe failure rates. Finally, the BMA model integrates climate projection data for future pipe failure forecasting. Overall, this research integrated physical, environmental, and operational factors speculated in contributing to failures of pipes and valves. The data analysis and methodology proposed in this study will help water utility managers and operators to make informed decision making for e cient design and construction of a new water supply systems or planning renewal and rehabilitation programs for old water supply systems. By implementing this methodology, water utilities can incorporate the most impacting pipe and valve failure factors, speci cally soil corrosion and climate change, in operational, tactic, and strategic level decision making.
Intervista a Valerio Magrelli
Creators: name: Magno, Luigi
Publisher: name: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo
Year: 2018

description: _
description: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo, N. 1 (2017)
Wall Resolved FLUID-STRUCTURE INTERACTION NUMERICAL SIMULATIONS of A MODERN wind turbine blade
Creators: name: Lahooti, Mohsen
name: Puraca, Rodulfo
name: Carmo, Bruno
name: Palacios, Rafael
name: Sherwin, Spencer
Publisher: name: Zenodo
Year: 2021
Subjects: Fluid-structure interaction, Large Eddy simulation, wind energy, wind turbine blades, aeroelasticity

description: Wall-resolved fluid-structure interaction (FSI) numerical simulations of the NREL 5 MW wind turbine blade
 are compared using two FSI approaches. The first method is based on high-fidelity Nektar++/SHARPy FSI framework,
 where the fluid governing equations are solved using high-order spectral/hp element method and the turbulent flow is
 resolved using Large Eddy Simulation (LES) on thick strips, while large-deformation dynamics of the structure are mod-
 elled using a geometrically exact nonlinear composite beam finite-element model. Thick strip method for the fluid reduces
 the computational cost by considering a series of smaller domains, each of which has a finite thickness in the spanwise
 direction. Hence, the overall flow over the blade is treated with a sectional approach, where in each of these sections,
 strips, the 3D flow is reconstructed locally. Tip-loss correction is used to compensate for the sectional approach over the
 blade. The second FSI approach is based on OpenFoam/Calculix coupling, where the second-order unstructured finite
 volume method approach is used for solving the three-dimensional flow equations and the flow turbulence is captured us-
 ing the k-ω SST model. The structural dynamics are modeled via second-order finite element method using standard solid
 elements. Effects of the solution fidelity on the prediction of aerodynamic forces as well as on the full three-dimensional
 flow modelling over the blade versus sectional representation of flow over the blade while incorporating the local three-
 dimensionality in each section and tip-correction are discussed. Further, significance of two approaches on modelling
 the slender blade, one using the beam mode and the other utilizing the full 3D solution of structure is addressed. Finally,
 assessment of computational cost and scalability of the two approaches are presented and discussed.
description: My Presentation Slides at COBEM 21
Pew Research Center: 2018 National Survey of Latinos
Creators: name: Pew Research Center
Publisher: name: Roper Center for Public Opinion Research
Year: 2018

description: Satisfaction with way things are going in country (1); personal financial situation (2); children will be better or worse off in their lifetime (1); prefer term Hispanic or Latino (1); how many years have you lived in United States (1); confidence in future of United States (1); President Donald Trump approval (1); enthusiasm about upcoming congressional elections (2); which party has more concern for Hispanics/Latinos (1); most important problem facing country today (1); Hispanics/Latinos better or worse off than a year ago (1); Trump administration policies' impact on Hispanics/Latinos (1); more difficult to to live as a Hispanic/Latino in United States in recent years (1); concerns about place in America now that Trump is president (1); participated in any protests or demonstrations to support immigrants rights since Trump became president (1); talked about immigration policy since Trump became president (1); worry that you, family, or close family could be deported (1); would you to come to United States again if you could do it again (1); better or worse conditions in United States or where you came from (2); fluency in languages (4); how would other people describe your race (1); negative experiences as a Hispanic/Latino in past 12 months (5); permanent legal status for children who came here illegally (1); expand wall across United States border with Mexico (1); amount of immigrants in United States (1); registered to vote (1); how often do you attend religious services (1).
Development of highly selective single sensor microfluidic-based gas detector
Creators: name: Paknahad, Mohammad
Publisher: name: University of British Columbia
Year: 2017

description: This research aims at the integration of gas sensors into microfluidics platforms to develop low-cost, portable, and highly selective (with a fast recovery time) detection tools for discrimination of volatile organic compounds (VOCs). The main advantage of the proposed device over previous microfluidic-based gas sensors is the enhanced selectivity by optimizing the microchannel geometry and implementing a novel multi-layer surface coating. These enhancements resulted in reducing the sensor recovery time to less than 150 seconds, as opposed to over 15 minutes reported in previous studies. A thorough study is also conducted to further investigate the effect of analyte polarity and the choice of channel surface material (creating different hydrophobicity) on gas discrimination. It is shown that the device segregation capability between different compounds highly depends on the target gas polarity and hydrophobicity of the channel surface material (reflecting its surface energy and interaction with the analyte). Finally, to eliminate the faulty effect of humidity on the sensor’s response, a diffusion-based humidity control membrane (made out of inorganic salts) is added to reduce and stabilize the level of relative humidity at 15%. The transient responses of the sensor in different humidity levels show that the proposed humidity control system also significantly enhances the selectivity of the device. A range of different target analytes including alcohols, ketones, and alkanes are tested using the proposed detector. The results show that the device can successfully differentiate between different gases (and even gas mixtures) at small concentrations (at the ppm level), showing the diagnostic power of the developed sensors. The device is then tested for wide range of applications including: 1) identification of wine samples for which different types of wines from different manufacturers and vintage years are differentiated; 2) monitoring tetrahydrocannabinol (THC) in air samples for potentially detecting the cannabis use; and 3) leakage detection along the pipeline in which the device was used for identifying pentane traces in a field test. This wide range of applications shows the power and versatility of the proposed gas detector technology.
La descrizione allegorica e la descrizione simbolica: una questione di definizioni
Creators: name: Ceserani, Remo
Publisher: name: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo
Year: 2018

description: Il presente contributo era stato pubblicato nel volume Raccontare e descrivere. Lo spazio nel romanzo dell’Ottocento, a cura di F. Fiorentino, Bulzoni, Roma 1997, pp. 21-44 («I libri dell’Associazione Sigismondo Malatesta. Studi di letteratura comparata e teatro», IX).
description: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo, N. 2 (2018)
Mutagenic and cytostatic activities of the Xylopia laevigata essential oil in human lymphocytes
Creators: name: Pereira, Tais Susane
name: Esquissato, Giovana Natiele Machado
name: Costa, Emmanoel Vilaça
name: de Lima Nogueira, Paulo Cesar
name: de Castro-Prado, Marialba Avezum Alves
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Biochemistry
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Neuroscience
subject: Pharmacology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: 60506 Virology

description: Hydro-distilled essential oil from leaves of Xylopia laevigata was characterized by GC-MS. Twenty-seven components were identified and the oil’s major constituents comprised germacrene D, bicyclogermacrene, (E)-caryophyllene and germacrene B. The cytotoxicity of the essential oil of X. laevigata (EOXL), determined by MTT and mitotic index methods in cultured human lymphocytes was observed in all tested concentrations. Cultures treated with EOXL demonstrated significant increase in the frequencies of micronuclei in the cytokinesis-block micronucleus assay (CBMN) and reduction of the cytokinesis-block proliferation index (CBPI) rates. Results demonstrated the cytostatic and mutagenic effects of EOXL, the latter for the first time.
Poliziesco, storia e cronaca nera. Conversazione con Alessandro Perissinotto
Creators: name: Di Benedetto, Angela
Publisher: name: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo
Year: 2018

description: Intervista ad Alessandro Perissinotto.
description: SigMa - Rivista di Letterature comparate, Teatro e Arti dello spettacolo, N. 2 (2018)
The Breakthrough Listen Search for Intelligent Life: Technosignature Search of 97 Nearby Galaxies
Creators: name: Choza, Carmen
name: Bautista, Daniel
name: Croft, Steve
name: Brzycki, Bryan
name: Siemion, Andrew
name: Bhattaram, Krishnakumar
name: Czech, Daniel
name: de Pater, Imke
name: Gajjar, Vishal
name: Isaacson, Howard
name: Lacker, Kevin
name: Lacki, Brian
name: Lebofsky, Matthew
name: MacMahon, David H. E.
name: Price, Danny
name: Schoultz, Sarah
name: Sheikh, Sofia
name: Varghese, Savin Shynu
name: Morgan, Lawrence
name: Drew, Jamie
name: Worden, S. Pete
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The Breakthrough Listen search for intelligent life is, to date, the most extensive technosignature search of nearby celestial objects. We present a radio technosignature search of the centers of 97 nearby galaxies, observed by Breakthrough Listen at the Robert C. Byrd Green Bank Telescope. We performed a narrowband Doppler drift search using the turboSETI pipeline with a minimum signal-to-noise parameter threshold of 10, across a drift rate range of $\pm$ 4 Hz\ $s^{-1}$, with a spectral resolution of 3 Hz and a time resolution of $\sim$ 18.25 s. We removed radio frequency interference by using an on-source/off-source cadence pattern of six observations and discarding signals with Doppler drift rates of 0. We assess factors affecting the sensitivity of the Breakthrough Listen data reduction and search pipeline using signal injection and recovery techniques and apply new methods for the investigation of the RFI environment. We present results in four frequency bands covering 1 -- 11 GHz, and place constraints on the presence of transmitters with equivalent isotropic radiated power on the order of $10^{26}$ W, corresponding to the theoretical power consumption of Kardashev Type II civilizations.
description: 25 pages, 22 figures
Continuity of Limit Surfaces of Locally Uniform Random Permutations
Creators: name: Sjöstrand, Jonas
Publisher: name: arXiv
Year: 2023
Subjects: subject: Probability (math.PR)
subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 49N99 (Primary) 60C05 (Secondary)

description: A locally uniform random permutation is generated by sampling $n$ points independently from some absolutely continuous distribution $ρ$ on the plane and interpreting them as a permutation by the rule that $i$ maps to $j$ if the $i$th point from the left is the $j$th point from below. As $n$ tends to infinity, decreasing subsequences in the permutation will appear as curves in the plane, and by interpreting these as level curves, a union of decreasing subsequences gives rise to a surface. In a recent paper by the author it was shown that, for any $r\ge0$, under the correct scaling as $n$ tends to infinity, the surface of the largest union of $\lfloor r\sqrt{n}\rfloor$ decreasing subsequences approaches a limit in the sense that it will come close to a maximizer of a specific variational integral (and, under reasonable assumptions, that the maximizer is essentially unique). In the present paper we show that there exists a continuous maximizer, provided that $ρ$ has bounded density and support.
 The key ingredient in the proof is a new theorem about real functions of two variables that are increasing in both variables: We show that, for any constant $C$, any such function can be made continuous without increasing the diameter of its image or decreasing anywhere the product of its partial derivatives clipped by $C$, that is the minimum of the product and $C$.
Global well-posedness for the micropolar fluid system in the critical Besov spaces
Creators: name: Chen, Qionglei
name: Miao, Changxing
Publisher: name: arXiv
Year: 2010
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We prove the global well-posedness for the 3-D micropolar fluid system in the critical Besov spaces by making a suitable transformation to the solutions and using the Fourier localization method, especially combined with a new $L^p$ estimate for the Green matrix to the linear system of the transformed equation. This result allows to construct global solutions for a class of highly oscillating initial data of Cannone's type. Meanwhile, we analyze the long behavior of the solutions and get some decay estimates.
description: 23pages
Current Legal Challenges to Abortion: Implications for Prenatal Genetics
Creators: name: Clayton, Ellen
name: Michie, Marsha
Publisher: name: Center for ELSI Resources and Analysis
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Ethics
subject: Science
subject: ELSI
subject: prenatal screening
subject: abortion
subject: Down Syndrome
subject: reproductive decision making

description: The ability to examine the health of the fetus has expanded dramatically in the last half century. Most of the time, the news is reassuring. However, prenatal screening and diagnosis detect genetic conditions in a small percentage of cases. Effective prenatal intervention for these conditions is still uncommon—few are treatable prenatally. Therefore, when their physician detects a congenital fetal condition, some people choose to terminate their pregnancies. For decades, states have varied widely in their willingness to provide access to prenatal testing and legal remedies when parents claim that they would have chosen to terminate the pregnancy had they known of the fetal condition. In addition to attempting to ban abortion early in pregnancy before prenatal diagnosis is possible, several states have sought—in some cases successfully—to limit or eliminate abortion as an option following prenatal diagnosis by implementing “reason bans”. These legislative activities prohibit a provider from performing an abortion when they are aware that fetal race, sex, or the presence of anomalies (such as Down syndrome, which is often mentioned by name in the statutes) are motivating the decision to terminate. This collection of literature outlines some of the issues posed by the implementation of “reason bans” and forbidding abortion early in pregnancy and asks what role prenatal screening and diagnosis can and should play if reproductive choice were no longer available. These issues are considered in light of longstanding evidence about the impacts of prenatal diagnosis on expectant parents, especially the pregnant person.
Scattering and Transformation of Waves on Heavy Particles in Magnetized Plasma
Creators: name: Nersisyan, Hrachya B.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The scattering and transformation of the waves propagating in magnetized plasma on a heavy stationary charged particle located at a plane plasma-vacuum boundary is considered. The scattering (transformation) occurs due to the nonlinear coupling of the incident wave with the polarization (shielding) cloud surrounding the particle. It is shown that the problem is reduced to the determination of the nonlinear (three index) dielectric tensor of magnetized plasma. The angular distribution and the cross section for scattering (transformation) of high-frequency ordinary and extraordinary waves and low-frequency upper-hybrid, low-hybrid, and magnetosonic waves are investigated within a cold plasma (hydrodynamic) model.
description: 14 pages, 6 figures