cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Towards an ecology of knowledge for sustainable food system education
Creators: name: Valley, William Cameron
Publisher: name: University of British Columbia
Year: 2014

description: This study investigates the Land, Food, and Community (LFC) series of core courses within the Faculty of Land and Food Systems at the University of British Columbia (Vancouver) as an example of a sustainable food system education (SFSE) program. SFSE programs are emerging across North America as an alternative approach to developing future professionals within the food system. SFSE programs share common curricular use of systems-based, inter- and trans- disciplinary, experiential learning approaches. The study has two components. The first component focuses on the theoretical framework of the LFC series. The second component focuses on experiences of a sample of students enrolled in a second-year course in 2012. Using a qualitative case study methodology, I incorporate autoethnographic experiences, document analysis, semi-structured interviews, and analysis of written responses to a dual-position food security problem to address the following research objectives: identify and situate the LFC theoretical framework within a diversity of scholarly domains; determine the impact of specific pedagogical strategies in the second-year course on students’ epistemic and ontological cognitive development (EOCD); and, investigate the correspondence between EOCD and systems competencies in addressing food systems problems. Results from the first component identify four key elements of the LFC theoretical framework: the ecology of knowledge, the community of learners, polycultures of the mind, and systems approaches. The elements are situated within Freirean critical constructivist learning theory, Bateson’s theory of ecological knowing, cognitive flexibility theory, and community- engaged scholarship. Results from the second component suggest that the pedagogical activities in the second-year course had an impact on participants’ EOCD by helping students understand the concepts of holism and pluralism as well as demonstrating the limitations of reductionism and the uncertainty of knowledge in ill-structured domains. Evidence suggests that systems thinking competencies are not being adequately developed in the second-year course. The study found limited evidence of correspondence between EOCD and the ability to apply systems principles to address a food system issue. The study concludes with a discussion on characteristics of a signature pedagogy for SFSE programs and a proposed scaffolding of EOCD and the development of systems thinking competencies across the LFC series.
Thermal Degradation of Adsorbed Bottle-Brush Macromolecules: Molecular Dynamics Simulation
Creators: name: Milchev, Andrey
name: Paturej, Jaroslaw
name: Rostiashvili, Vakhtang G.
name: Vilgis, Thomas A.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The scission kinetics of bottle-brush molecules in solution and on an adhesive substrate is modeled by means of Molecular Dynamics simulation with Langevin thermostat. Our macromolecules comprise a long flexible polymer backbone with $L$ segments, consisting of breakable bonds, along with two side chains of length $N$, tethered to each segment of the backbone. In agreement with recent experiments and theoretical predictions, we find that bond cleavage is significantly enhanced on a strongly attractive substrate even though the chemical nature of the bonds remains thereby unchanged. We find that the mean bond life time $$ decreases upon adsorption by more than an order of magnitude even for brush molecules with comparatively short side chains $N=1 ÷4$. The distribution of scission probability along the bonds of the backbone is found to be rather sensitive regarding the interplay between length and grafting density of side chains. The life time $$ declines with growing contour length $L$ as $\propto L^{-0.17}$, and with side chain length as $\propto N^{-0.53}$. The probability distribution of fragment lengths at different times agrees well with experimental observations. The variation of the mean length $L(t)$ of the fragments with elapsed time confirms the notion of the thermal degradation process as a first order reaction.
description: 15 pages, 7 figures
Antarctoperlinae Enderlein 1909
Creators: name: McLellan, Ian D.
name: Zwick, Peter
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Plecoptera
Gripopterygidae

description: Antarctoperlinae Enderlein, 1909 This subfamily is well supported, also by larval characters. These include the very rounded massive head with a frontal depression, ring ‐ shaped abdominal segments lacking a soft pleural area, the long parallel ‐ sided posteriorly extended segment X which covers the retracted gills and the paraprocts from above, and the modified cerci. The cerci are short and thin, the apical section is thread ‐ like. The terrestrial Megandiperla with its very short but thick conical cerci is the only exception. Larvae and adults lack tibial spurs. However, larvae of some other South American taxa also lack them (see the key). Additional characters characteristic of larvae of Antarctoperlinae but not shared by all of them are the thickened and often very pilose base of antennal flagellum, prominent or extended pronotal corners, paired dorsal processes on head, pronotum and/or abdomen, and camouflage of detritus containing fine sand firmly attached to body hairs. Unassociated Larvae In the Flint collection there are Antarctoperlinae larvae without associated adults. Several are last instar specimens but none is sufficiently mature to dissect the pharate adult. These larvae are described below, under informal designations.
description: Published as part of McLellan, Ian D. & Zwick, Peter, 2007, New Species Of And Keys To South American Gripopterygidae (Plecoptera), pp. 20-42 in Illiesia 3 (4) on page 27, DOI: 10.5281/zenodo.4758655
Ανάδραση από 14 εκπαιδευτικούς και εκπαιδευτές ενηλίκων σχετικά με τη μέθοδο της Μετασχηματίζουσας Μάθησης μέσω της Αισθητικής Εμπειρίας
Creators: name: Γιωτόπουλος, Γεώργιος
name: Στασινοπούλου, Ευσταθία
Publisher: name: Zenodo
Year: 2016
Subjects: Κριτική σκέψη
Μετασχηματίζουσα Μάθηση μέσω της Αισθητικής Εμπειρίας
παραδοχές
Mezirow

description: Στην παρούσα εργασία• γίνεται καταρχάς συνοπτική παρουσίαση της μεθόδου του Α. Κόκκου «Μετασχηματίζουσα Μάθηση μέσω της αισθητικής εμπειρίας»και κατόπιν εφαρμογή της σε 14εκπαιδευτικούς και εκπαιδευτές ενηλίκων προκειμένου να υπάρξει ανάδραση και αξιολόγηση της μεθόδου. Πρόκειται για «μια μέθοδο παρατήρησης των τεχνών που ενισχύει την αυτοδυναμία της σκέψης» (Κόκκος, 2011a:72). Η μεθοδολογία αυτή έχει εφαρμοστεί και από άλλους ερευνητές και προγράμματα, όπως η Ράικου (2011;2013), ArtiT (2012), Καραλής &Ράικου (2012).Ο σκοπός ήταν η παραγωγή κριτικού στοχασμού από τους εκπαιδευόμενους με τη χρήση της μεθόδου αυτής. Ως ερευνητικό εργαλείο χρησιμοποιήθηκε η ηχογραφημένη συνέντευξη καθώς και η μετέπειτα ανάλυση περιεχομένου. Αποδεικνύεται ότι η μέθοδος του Α. Κόκκου, μπορεί να συμβάλλει στην ανάπτυξη στοχαστικής διάθεσης και να βοηθήσει στην ανάπτυξη κριτικής σκέψης τους συμμετέχοντες.
description: {"references": ["\u0393\u03b9\u03c9\u03c4\u03cc\u03c0\u03bf\u03c5\u03bb\u03bf\u03c2, \u0393. (2014). \u0391\u03bd\u03ac\u03c0\u03c4\u03c5\u03be\u03b7 \u03ba\u03c1\u03b9\u03c4\u03b9\u03ba\u03ae\u03c2 \u03c3\u03ba\u03ad\u03c8\u03b7\u03c2 \u03bc\u03b5 \u03c7\u03c1\u03ae\u03c3\u03b7 \u03c4\u03b7\u03c2 \u03bc\u03b5\u03b8\u03cc\u03b4\u03bf\u03c5 \u00ab\u039c\u03b5\u03c4\u03b1\u03c3\u03c7\u03b7\u03bc\u03b1\u03c4\u03af\u03b6\u03bf\u03c5\u03c3\u03b1 \u039c\u03ac\u03b8\u03b7\u03c3\u03b7 \u03bc\u03ad\u03c3\u03c9 \u03c4\u03b7\u03c2 \u0391\u03b9\u03c3\u03b8\u03b7\u03c4\u03b9\u03ba\u03ae\u03c2 \u0395\u03bc\u03c0\u03b5\u03b9\u03c1\u03af\u03b1\u03c2\u00bb \u03c3\u03b5 \u03bc\u03b1\u03b8\u03b7\u03c4\u03ad\u03c2 \u03c4\u03b7\u03c2 \u03a4\u03c5\u03c0\u03b9\u03ba\u03ae\u03c2 \u0395\u03ba\u03c0\u03b1\u03af\u03b4\u03b5\u03c5\u03c3\u03b7\u03c2, 1\u03bf \u03a0\u03b1\u03bd\u03b5\u03bb\u03bb\u03ae\u03bd\u03b9\u03bf \u03a3\u03c5\u03bd\u03ad\u03b4\u03c1\u03b9\u03bf \u03b3\u03b9\u03b1 \u03c4\u03bf eTwinning \u03ba\u03b1\u03b9 \u03ac\u03bb\u03bb\u03c9\u03bd \u0395\u03c5\u03c1\u03c9\u03c0\u03b1\u03ca\u03ba\u03ce\u03bd \u03c0\u03c1\u03bf\u03b3\u03c1\u03b1\u03bc\u03bc\u03ac\u03c4\u03c9\u03bd \u03c3\u03c5\u03bd\u03b5\u03c1\u03b3\u03b1\u03c4\u03b9\u03ba\u03cc\u03c4\u03b7\u03c4\u03b1\u03c2 \u03b3\u03b9\u03b1 \u03c4\u03b7\u03bd \u0391/\u03b8\u03bc\u03b9\u03b1 \u03ba\u03b1\u03b9 \u0392/\u03b8\u03bc\u03b9\u03b1 \u0395\u03ba\u03c0/\u03c3\u03b7, \u03a0\u03ac\u03c4\u03c1\u03b1, 2014. DOI: 10.13140/RG.2.1.1700.6166"]}
Det-SLAM: A semantic visual SLAM for highly dynamic scenes using Detectron2
Creators: name: Eslamian, Ali
name: Ahmadzadeh, Mohammad R.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Robotics (cs.RO)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: According to experts, Simultaneous Localization and Mapping (SLAM) is an intrinsic part of autonomous robotic systems. Several SLAM systems with impressive performance have been invented and used during the last several decades. However, there are still unresolved issues, such as how to deal with moving objects in dynamic situations. Classic SLAM systems depend on the assumption of a static environment, which becomes unworkable in highly dynamic situations. Several methods have been presented to tackle this issue in recent years, but each has its limitations. This research combines the visual SLAM systems ORB-SLAM3 and Detectron2 to present the Det-SLAM system, which employs depth information and semantic segmentation to identify and eradicate dynamic spots to accomplish semantic SLAM for dynamic situations. Evaluation of public TUM datasets indicates that Det-SLAM is more resilient than previous dynamic SLAM systems and can lower the estimated error of camera posture in dynamic indoor scenarios.
description: 5 pages, 2 figures
Evolution of the Solar Nebula and Planet Growth Under the Influence of Photoevaporation
Creators: name: Mitchell, Tyler R.
name: Stewart, Glen R.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The recent development of a new minimum mass solar nebula, under the assumption that the giant planets formed in the compact configuration of the Nice model, has shed new light on planet formation in the solar system. Desch previously found that a steady state protoplanetary disk with an outer boundary truncated by photoevaporation by an external massive star would have a steep surface density profile. In a completely novel way, we have adapted numerical methods for solving propagating phase change problems to astrophysical disks. We find that a one-dimensional time-dependent disk model that self-consistently tracks the location of the outer boundary produces shallower profiles than those predicted for a steady state disk. The resulting surface density profiles have a radial dependence of Sigma(r) αr^(-1.25+0.88-0.33) with a power-law exponent that in some models becomes as large as ~Sigma(r) αr^(-2.1). The evolutionary timescales of the model disks can be sped up or slowed down by altering the amount of far-ultraviolet flux or the viscosity parameter alpha. Slowing the evolutionary timescale by decreasing the incident far ultraviolet flux, or similarly by decreasing alpha, can help to grow planets more rapidly, but at the cost of decreased migration timescales. Although they similarly affect relevant timescales, changes in the far ultraviolet flux or alpha produce disks with drastically different outer radii. Despite their differences, these disks are all characterized by outward mass transport, mass loss at the outer edge, and a truncated outer boundary. The transport of mass from small to large radii can potentially prevent the rapid inward migration of Jupiter and Saturn, while at the same time supply enough mass to the outer regions of the disk for the formation of Uranus and Neptune.
description: 16 pages, 12 figures. Accepted for publication in The Astrophysical Journal
Dynamic image recognition in a spiking neuron network supplied by astrocytes
Creators: name: Stasenko, Sergey V.
name: Kazantsev, Victor B.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: FOS: Biological sciences

description: Mathematical model of spiking neuron network (SNN) supplied by astrocytes is investigated. The astrocytes are specific type of brain cells which are not electrically excitable but inducing chemical modulations of neuronal firing. We analyzed how the astrocytes influence on images encoded in the form of dynamic spiking pattern of the SNN. Serving at much slower time scale the astrocytic network interacting with the spiking neurons can remarkably enhance the image recognition quality. Spiking dynamics was affected by noise distorting the information image. We demonstrated that the activation of astrocyte can significantly suppress noise influence improving dynamic image representation by the SNN.
description: arXiv admin note: text overlap with arXiv:2210.01014
A Non-Parametric Estimate of Mass 'Scoured' in Galaxy Cores
Creators: name: Hopkins, Philip F.
name: Hernquist, Lars
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We present a simple estimate of the mass 'deficits' in cored spheroids, as a function of galaxy mass and radius within the galaxy. Previous attempts to measure such deficits depended on fitting some functional form to the profile at large radii and extrapolating inwards; this is sensitive to the assumed functional form and does not allow for variation in nuclear profile shapes. We take advantage of larger data sets to directly construct stellar mass profiles of observed systems and measure the stellar mass enclosed in a series of physical radii (M(
description: 11 pages, 5 figures, accepted to MNRAS
Quasi-one-dimensional antiferromagnetism and multiferroicity in CuCrO$_4$
Creators: name: Law, J. M.
name: Reuvekamp, P.
name: Glaum, R.
name: Lee, C.
name: Kang, J.
name: Whangbo, M. -H.
name: Kremer, R. K.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The bulk magnetic properties of the new quasi-one-dimensional Heisenberg antiferromagnet, CuCrO$_4$, were characterized by magnetic susceptibility, heat capacity, optical spectroscopy, EPR and dielectric capacitance measurements and density functional evaluations of the intra- and interchain spin exchange interactions. We found type-II multiferroicity below the Néel temperature of 8.2(5) K, arising from competing antiferromagnetic nearest-neighbor ($J_{\rm nn}$) and next-nearest-neighbor ($J_{\rm nnn}$) intra-chain spin exchange interactions. Experimental and theoretical results indicate that the ratio $J_{\rm nn}/J_{\rm nnn}$ is close to 2, putting CuCrO$_4$ in the vicinity of the Majumdar-Ghosh point.
description: 9 pages, 8 figures, submitted to PRB
Failure of neuron network coherence induced by SARS-CoV-2-infected astrocytes
Creators: name: Stasenko, Sergey V.
name: Hramov, Alexander E.
name: Kazantsev, Victor B.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: FOS: Biological sciences

description: Coherent activations of brain neuron networks underlay many physiological functions associated with various behavioral states. These synchronous fluctuations in the electrical activity of the brain are also referred to as brain rhythms. At the cellular level, the rhythmicity can be induced by various mechanisms of intrinsic oscillations in neurons or network circulation of excitation between synaptically coupled neurons. One of the specific mechanisms concerns the activity of brain astrocytes that accompany neurons and can coherently modulate synaptic contacts of neighboring neurons, synchronizing their activity. Recent studies have shown that coronavirus infection (Covid-19), entering the central nervous system and infecting astrocytes, causes various metabolic disorders. Specifically, Covid-19 can depress the synthesis of astrocytic glutamate and GABA. It is also known that in the postcovid state, patients may suffer from symptoms of anxiety and impaired cognitive functions, which may be a consequence of disturbed brain rhythms. We propose a mathematical model of a spiking neural network accompanied by astrocytes capable to generate quasi-synchronous rhythmic bursting discharges. The model predicts that if the astrocytes are infected, and the release of glutamate is depressed, then normal burst rhythmicity suffers dramatically. Interestingly, in some cases, the failure of network coherence may be intermittent with intervals of normal rhythmicity, or the synchronization can completely disappears.
\emph{In-situ} determination of astro-comb calibrator lines to better than 10 cm s$^{-1}$
Creators: name: Li, C. -H.
name: Glenday, A.
name: Benedick, A. J.
name: Chang, G.
name: Chen, L. -J.
name: Cramer, C.
name: Fendel, P.
name: Furesz, G.
name: Kärtner, F.
name: Korzennik, S.
name: Phillips, D.
name: Sasselov, D.
name: Szentgyorgyi, A.
name: Walsworth, R.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Instrumentation and Detectors (physics.ins-det)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Improved wavelength calibrators for high-resolution astrophysical spectrographs will be essential for precision radial velocity (RV) detection of Earth-like exoplanets and direct observation of cosmological deceleration. The astro-comb is a combination of an octave-spanning femtosecond laser frequency comb and a Fabry-Pérot cavity used to achieve calibrator line spacings that can be resolved by an astrophysical spectrograph. Systematic spectral shifts associated with the cavity can be 0.1-1 MHz, corresponding to RV errors of 10-100 cm/s, due to the dispersive properties of the cavity mirrors over broad spectral widths. Although these systematic shifts are very stable, their correction is crucial to high accuracy astrophysical spectroscopy. Here, we demonstrate an \emph{in-situ} technique to determine the systematic shifts of astro-comb lines due to finite Fabry-Pérot cavity dispersion. The technique is practical for implementation at a telescope-based spectrograph to enable wavelength calibration accuracy better than 10 cm/s.
description: 11 pages, 7 figures
Spectral Properties of the Symmetry Generators of Conformal Quantum Mechanics: A Path-Integral Approach
Creators: name: Camblong, H. E.
name: Chakraborty, A.
name: Lopez-Duque, P.
name: Ordóñez, C. R.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: A path-integral approach is used to study the spectral properties of the generators of the SO(2,1) symmetry of conformal quantum mechanics (CQM). In particular, we consider the CQM version that corresponds to the weak-coupling regime of the inverse square potential. We develop a general framework to characterize a generic symmetry generator $G$ (linear combinations of the Hamiltonian $H$, special conformal operator $K$, and dilation operator $D$), from which the path-integral propagators follow, leading to a complete spectral decomposition. This is done for the three classes of operators: elliptic, parabolic, and hyperbolic. We also highlight novel results for the hyperbolic operators, with a continuous spectrum, and their quantum-mechanical interpretation. The spectral technique developed for the eigensystem of continuous-spectrum operators can be generalized to other operator problems.
description: Updated with published version
Kepler observations of variability in B-type stars
Creators: name: Balona, L. A.
name: Pigulski, A.
name: De Cat, P.
name: Handler, G.
name: Gutierrez-Soto, J
name: Engelbrecht, C. A.
name: Frescura, F.
name: Briquet, M.
name: Cuypers, J.
name: Daszynska-Daszkiewicz, J.
name: Degroote, P.
name: Dukes, R. J.
name: Garcia, R. A.
name: Green, E. M.
name: Heber, U.
name: Kawaler, S. D.
name: Ostensen, R.
name: Pricopi, D.
name: Roxburgh, I.
name: Salmon, S.
name: Smith, M. A.
name: Suarez, J. C.
name: Suran, M.
name: Szabo, R.
name: Uytterhoeven, K.
name: Christensen-Dalsgaard
name: Kjeldsen, H.
name: Caldwell, D. A.
name: Girouard, F. R.
name: Sanderfer, D. T.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The analysis of the light curves of 48 B-type stars observed by Kepler is presented. Among these are 15 pulsating stars, all of which show low frequencies characteristic of SPB stars. Seven of these stars also show a few weak, isolated high frequencies and they could be considered as SPB/beta Cep hybrids. In all cases the frequency spectra are quite different from what is seen from ground-based observations. We suggest that this is because most of the low frequencies are modes of high degree which are predicted to be unstable in models of mid-B stars. We find that there are non-pulsating stars within the beta Cep and SPB instability strips. Apart from the pulsating stars, we can identify stars with frequency groupings similar to what is seen in Be stars but which are not Be stars. The origin of the groupings is not clear, but may be related to rotation. We find periodic variations in other stars which we attribute to proximity effects in binary systems or possibly rotational modulation. We find no evidence for pulsating stars between the cool edge of the SPB and the hot edge of the delta Sct instability strips. None of the stars show the broad features which can be attributed to stochastically-excited modes as recently proposed. Among our sample of B stars are two chemically peculiar stars, one of which is a HgMn star showing rotational modulation in the light curve.
description: 19 pages, 11 figures, 4 tables
Water access and governance among indigenous and migrant low income communities in the Greater Accra Metropolitan Area (GAMA), Ghana
Creators: name: Dapaah, Elizabeth Koryoo
Publisher: name: University of British Columbia
Year: 2014

description: Access to potable water remains a key concern for most developing countries, especially across the sub-Saharan African sub-region. Although countries such as Ghana have already declared success in attaining its MDG target of halving its population without access to potable water ahead of the 2015 target date, there are disparities in water access across the country. This disparity is notable in growing urban areas such as Accra, the national capital, where access to potable water remains a daunting challenge especially for many neighborhoods located in low income enclaves of the city. Adopting a comparative approach, this research aims to elicit the everyday accessibility options and coping strategies of two low income neighborhoods; one indigenous (Ga Mashie) and one migrant (Madina), located in the metropolitan region of Accra. The study uses data from a two and half months of fieldwork conducted in both communities in Accra, Ghana. It includes a survey of 200 households in Ga Mashie and Madina, group discussions, and semi-structured interviews with local community leaders. Drawing on concepts of entitlement, social capital, vulnerability and water governance, the study analyzes the everyday lived experiences of water access in these communities. Results of the study show that while there are qualitative differences in water access between both communities, they both rely on informal water vendors for their water supply. Also, among the many social problems in both communities, water was considered to be among their biggest concerns. However, this notion held by the respondents in both communities was not shared by local public officials in Ga Mashie, where officials discounted the existence of a water problem. Moreover, in some notable ways, Madina appears to be more resilient in times of water shortages than Ga Mashie, contrary to what this study initially hypothesized. In conclusion, this study suggests that care must be taken in proposals for water governance reforms in particular settings since different localities likely call for different responses. For a sustainable governance outcome, there is the need to promote models that tend to account for the roles and needs of different social groups at the local level.
Doping a Wigner-Mott insulator: Exotic charge orders in transition-metal dichalcogenide moiré heterobilayers
Creators: name: Tan, Yuting
name: Tsang, Pak Ki Henry
name: Dobrosavljević, Vladimir
name: Rademaker, Louk
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The moiré pattern induced by lattice mismatch in transition-metal dichalcogenide heterobilayers causes the formation of flat bands, where interactions dominate the kinetic energy. At fractional fillings of the flat valence band, the long-range electron interactions then induce Wigner-Mott crystals. In this Letter we investigate the nontrivial electronic phases appearing away from commensurate fillings. Here, competing phases arise that are either characterized as doped Wigner-Mott charge transfer insulators or alternatively, a novel state with frozen charge order yet is conducting: the 'electron slush'. We propose that an extremely spatially inhomogeneous local density of states can serve as a key signature of the electron slush.
The Complexity of Reasoning about Spatial Congruence
Creators: name: Cristani, M.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: In the recent literature of Artificial Intelligence, an intensive research effort has been spent, for various algebras of qualitative relations used in the representation of temporal and spatial knowledge, on the problem of classifying the computational complexity of reasoning problems for subsets of algebras. The main purpose of these researches is to describe a restricted set of maximal tractable subalgebras, ideally in an exhaustive fashion with respect to the hosting algebras. In this paper we introduce a novel algebra for reasoning about Spatial Congruence, show that the satisfiability problem in the spatial algebra MC-4 is NP-complete, and present a complete classification of tractability in the algebra, based on the individuation of three maximal tractable subclasses, one containing the basic relations. The three algebras are formed by 14, 10 and 9 relations out of 16 which form the full algebra.
Passive Bias-Free Nonreciprocal Metasurfaces Based on Nonlinear Quasi-Bound States in the Continuum
Creators: name: Cotrufo, Michele
name: Cordaro, Andrea
name: Sounas, Dimitrios L.
name: Polman, Albert
name: Alù, Andrea
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Nonreciprocal devices - in which light is transmitted with different efficiencies along opposite directions - are key technologies for modern photonic applications, yet their compact and miniaturized implementation remains an open challenge. Among different avenues, nonlinearity-induced nonreciprocity has attracted significant attention due to the absence of external bias and integrability within conventional material platforms. So far, nonlinearity-induced nonreciprocity has been demonstrated only in guided platforms using high-Q resonators. Here, we demonstrate ultrathin optical metasurfaces with large nonreciprocal response for free-space radiation based on silicon third-order nonlinearities. Our metasurfaces combine an out-of-plane asymmetry - necessary to obtain nonreciprocity - with in-plane broken symmetry, which finely tunes the radiative linewidth of quasi-bound states in the continuum (q-BICs). Third-order nonlinearities naturally occurring in silicon, engaged by q-BICs, are shown to enable over 10 dB of nonreciprocal transmission while maintaining less than 3 dB in insertion loss. The demonstrated devices merge the field of nonreciprocity with ultrathin metasurface technologies, offering an exciting functionality for signal processing and routing, communications, and protection of high-power laser cavities.
description: 17 pages, 5 figures in main text. 9 pages, 3 figures in supplemental material
Plugin para geração automática do Cutter-Sanborn no software Koha
Creators: name: Brasileiro, Italo Barbosa
Publisher: name: Zenodo
Year: 2019
Subjects: Plugin
Open source
Koha

description: Este plugin permite a geração automática do Cutter-Sanborn na planilha bibliográfica, do software Koha.
description: O código do plugin está disponível  também no endereço https://github.com/olatiitalo/cutterPlugin/tree/master
Model Order Selection with Variational Autoencoding
Creators: name: Baur, Michael
name: Weißer, Franz
name: Böck, Benedikt
name: Utschick, Wolfgang
Publisher: name: arXiv
Year: 2022
Subjects: subject: Signal Processing (eess.SP)
subject: Information Theory (cs.IT)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Classical methods for model order selection often fail in scenarios with low SNR or few snapshots. Deep learning-based methods are promising alternatives for such challenging situations as they compensate lack of information in the available observations with training on large datasets. This manuscript proposes an approach that uses a variational autoencoder (VAE) for model order selection. The idea is to learn a parameterized conditional covariance matrix at the VAE decoder that approximates the true signal covariance matrix. The method is unsupervised and only requires a small representative dataset for calibration after training the VAE. Numerical simulations show that the proposed method outperforms classical methods and even reaches or beats a supervised approach depending on the considered snapshots.
description: Accepted for publication at IEEE SPAWC 2023
Thelepus Leuckart 1849
Creators: name: Hsueh, Pan-Wen
name: Li, Kuo-Rong
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Terebellida
Terebellidae
Thelepus

description: Genus Thelepus Leuckart, 1849
 Type species. Thelepus cincinnataus (Fabricius, 1780)
 Remarks. According to Hsueh & Li (2016), forty-eight species are currently recognised for the genus, and recently another two species have been described from Brazilian waters (Carrerette et al. in press). The present study therefore increases the number of known species for this genus to 52. Of these, only five were previously recorded from Chinese waters, including the two described in this paper.
description: Published as part of Hsueh, Pan-Wen & Li, Kuo-Rong, 2017, Additions of new species to Thelepus (Thelepodidae), with description of a new Terebellides (Trichobranchidae) from Taiwan, pp. 429-439 in Zootaxa 4244 (3) on page 430, DOI: 10.11646/zootaxa.4244.3.10, http://zenodo.org/record/432117
Finding structural anomalies in graphs by means of quantum walks
Creators: name: Feldman, Edgar
name: Hillery, Mark
name: Lee, Hai-Woong
name: Reitzner, Daniel
name: Zheng, Hongjun
name: Buzek, Vladimir
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We explore the possibility of using quantum walks on graphs to find structural anomalies, such as extra edges or loops, on a graph. We focus our attention on star graphs, whose edges are like spokes coming out of a central hub. If there are $N$ spokes, we show that a quantum walk can find an extra edge connecting two of the spokes or a spoke with a loop on it in $O(\sqrt{N})$ steps. We initially find that if all of the spokes have loops except one, the walk will not find the spoke without a loop, but this can be fixed if we choose the phase with which the particle is reflected from the vertex without the loop. Consequently, quantum walks can, under some circumstances, be used to find structural anomalies in graphs.
A method to generate complex quasi-nondiffracting optical lattices
Creators: name: Lopez-Aguayo, Servando
name: Kartashov, Yaroslav V.
name: Vysloukh, Victor A.
name: Torner, Lluis
Publisher: name: arXiv
Year: 2010
Subjects: subject: Optics (physics.optics)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We put forward a powerful technique that allows generating quasi-non-diffracting light beams with a variety of complex transverse shapes and topologies. We show that, e.g., spiraling patterns, patterns featuring curved or bent bright stripes, or patterns featuring arbitrary combinations of harmonic, Bessel, Mathieu and parabolic beams occupying different domains in the transverse plane can be produced. The quasi-non-diffracting patterns open up a wealth of opportunities for the manipulation of matter and optical waves, colloidal and living particles, with applications in biophysics, and quantum, nonlinear and atom optics.
description: 14 pages, 6 figures, to appear in Physical Review Letters
New Perspectives for QCD Physics at the LHC
Creators: name: Brodsky, Stanley J.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: I review a number of topics where conventional wisdom relevant to hadron physics at the LHC has been challenged. For example, the initial-state and final-state interactions of the quarks and gluons entering perturbative QCD hard-scattering subprocesses lead to the breakdown of traditional concepts of factorization and universality for transverse-momentum-dependent observables at leading twist. These soft-gluon rescattering effect produce single-spin asymmetries, the breakdown of the Lam-Tung relation in Drell-Yan reactions, as well as diffractive deep inelastic scattering, The antishadowing of nuclear structure functions is predicted to depend on the flavor quantum numbers of each quark and antiquark. Isolated hadrons can be produced at large transverse momentum directly within a hard higher-twist QCD subprocess, rather than from jet fragmentation, even at the LHC. Such "direct" processes can explain the observed deviations from pQCD predictions of the power-law fall-off of inclusive hadron cross sections as well as the "baryon anomaly" seen in high-centrality heavy-ion collisions at RHIC. The intrinsic charm contribution to the proton structure function at high x can explain the large rate for high p_T photon plus charm-jet events observed at the Tevatron and imply a large production rate for charm and bottom jets at high p_T at the LHC, as well as a novel mechanism for Higgs and Z^0 production at high x_F. The light-front wavefunctions derived in AdS/QCD can be used to calculate jet hadronization at the amplitude level. The elimination of the renormalization scale ambiguity for the QCD coupling using the scheme-independent BLM method will increase the sensitivity of searches for new physics at the LHC. The implications of "in-hadron condensates" for the QCD contribution to the cosmological constant are also discussed.
description: Invited talk, presented at the 5th Workshop on High P_T Physics at the LHC held at the Instituto de Ciencias Nucleares of the Universidad National Automata de Mexico in Mexico City, September 27-October 1, 2010
Reasoning within Fuzzy Description Logics
Creators: name: Straccia, U.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Description Logics (DLs) are suitable, well-known, logics for managing structured knowledge. They allow reasoning about individuals and well defined concepts, i.e., set of individuals with common properties. The experience in using DLs in applications has shown that in many cases we would like to extend their capabilities. In particular, their use in the context of Multimedia Information Retrieval (MIR) leads to the convincement that such DLs should allow the treatment of the inherent imprecision in multimedia object content representation and retrieval. In this paper we will present a fuzzy extension of ALC, combining Zadeh's fuzzy logic with a classical DL. In particular, concepts becomes fuzzy and, thus, reasoning about imprecise concepts is supported. We will define its syntax, its semantics, describe its properties and present a constraint propagation calculus for reasoning in it.
Dissipative defect modes in periodic structures
Creators: name: Kartashov, Yaroslav V.
name: Konotop, Vladimir V.
name: Vysloukh, Victor A.
name: Torner, Lluis
Publisher: name: arXiv
Year: 2010
Subjects: subject: Optics (physics.optics)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We show that periodic optical lattices imprinted in cubic nonlinear media with strong two-photon absorption and localized linear gain landscapes support stable dissipative defect modes in both focusing and defocusing media. Their shapes and transverse extent are determined by the propagation constant that belongs to a gap of the lattice spectrum which, in turn, is determined by the relation between gain and losses. One-hump and two-hump dissipative defect modes are obtained.
description: 4 pages, 3 figures
Investigating the myelin water fraction as a function of TR and the intra/extra cellular water geometric mean T2 as a function of refocusing interval
Creators: name: Ahmadi, Tara
Publisher: name: University of British Columbia
Year: 2014

description: In this thesis two studies were done using MRI. In chapter two, in vivo 3.0 T MRI data from white matter and grey matter in brain from 4 healthy volunteers was studied using a multi component T₂ relaxation analysis. The goal of this study was to find the dependence of myelin water fraction (MWF), the ratio of water in myelin bilayers to the total water component, with the repetition time of the MR sequence TR. Results showed that MWF increased with decreasing TR time. This behavior is believed to be influenced by the exchange of water between the myelin water and the intra/extracellular water pools. Several models were explored to explain this result, including a fast exchange model, a slow exchange model and a hybrid model in which myelin was proposed to contain regions of fast exchange and regions of slow exchange. In chapter three, we addressed the questions: Does the intra/extra cellular (IE) water geometric mean T₂ (gmT₂) of white and grey matter depend upon the refocusing interval? To answer these questions IE water gmT₂ times for different white and grey matter regions of interest were obtained from 5 healthy subjects. It was found that IE water gmT₂ times from both white matter and grey matter tissue decreased by approximately the same amount with refocusing interval prolongation from 10ms to 40 ms. Several mechanisms for this dependence were considered, including water exchange, existence of myelin, non-heme iron accumulation, or the effect of blood oxygenation. In this case, based on our simulations, exchange did not appear to play a role. Non-heme iron accumulation was related to T₂ time but not to the change in T₂ with echo spacing. Deoxygenation of blood results in the presence of paramagnetic deoxyhemoglobin (dHb), which increases the magnetic susceptibility, and thus the local magnetic field, which can shorten the transverse relaxation time; however, this mechanism would be expected to affect grey matter T₂’s more than white matter T₂s.
Relativistic Electromagnetic Mass Models With Cosmological Variable$Λ$ in Spherically Symmetric Anisotropic Source
Creators: name: Tiwari, R. N.
name: Ray, Saibal
name: Bhadra, Sumana
Publisher: name: arXiv
Year: 2011
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: A class of exact solutions for the Einstein-Maxwell field equations are obtained by assuming the erstwhile cosmological constant $ Λ$ to be a space-variable scalar, viz., $ Λ=Λ(r) $. The source considered here is static, spherically symmetric and anisotropic charged fluid. The solutions obtained are matched continuously to the exterior Reissner-Nordström solution and each of the four solutions represents an electromagnetic mass model.
description: 10 Latex pages
Shocks and Universal Statistics in (1+1)-Dimensional Relativistic Turbulence
Creators: name: Liu, Xiao
name: Oz, Yaron
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: We propose that statistical averages in relativistic turbulence exhibit universal properties. We consider analytically the velocity and temperature differences structure functions in the (1+1)-dimensional relativistic turbulence in which shock waves provide the main contribution to the structure functions in the inertial range. We study shock scattering, demonstrate the stability of the shock waves, and calculate the anomalous exponents. We comment on the possibility of finite time blowup singularities.
description: 37 pages, 7 figures
An Analysis of Reduced Error Pruning
Creators: name: Elomaa, T.
name: Kaariainen, M.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Top-down induction of decision trees has been observed to suffer from the inadequate functioning of the pruning phase. In particular, it is known that the size of the resulting tree grows linearly with the sample size, even though the accuracy of the tree does not improve. Reduced Error Pruning is an algorithm that has been used as a representative technique in attempts to explain the problems of decision tree learning. In this paper we present analyses of Reduced Error Pruning in three different settings. First we study the basic algorithmic properties of the method, properties that hold independent of the input decision tree and pruning examples. Then we examine a situation that intuitively should lead to the subtree under consideration to be replaced by a leaf node, one in which the class label and attribute values of the pruning examples are independent of each other. This analysis is conducted under two different assumptions. The general analysis shows that the pruning probability of a node fitting pure noise is bounded by a function that decreases exponentially as the size of the tree grows. In a specific analysis we assume that the examples are distributed uniformly to the tree. This assumption lets us approximate the number of subtrees that are pruned because they do not receive any pruning examples. This paper clarifies the different variants of the Reduced Error Pruning algorithm, brings new insight to its algorithmic properties, analyses the algorithm with less imposed assumptions than before, and includes the previously overlooked empty subtrees to the analysis.
Electron and Photon Performance and Electron p_T Spectrum Measurement with ATLAS in pp Collisions at sqrt(s) = 7 TeV
Creators: name: Snyder, Scott
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We discuss the early performance of the reconstruction of electrons and photons at ATLAS with a center-of-mass energy of 7 TeV. Using a data sample of about 15 nb^-1, we present a measurement of the transverse momentum distribution of inclusive electrons, as well as an observation of prompt photons and a measurement of the purity of this sample. We also demonstrate the reconstruction of J/psi mesons with a data sample of 78 nb^-1.
description: 4 pages, 6 figures. To be published in the proceedings of the 35th International Conference of High Energy Physics, July 22-28, 2010, Paris, France
Discrete Whittaker processes
Creators: name: O'Connell, Neil
Publisher: name: arXiv
Year: 2022
Subjects: subject: Probability (math.PR)
subject: Number Theory (math.NT)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics

description: We consider a Markov chain on non-negative integer arrays of a given shape (and satisfying certain constraints) which is closely related to fundamental $SL(r+1,\mathbb{R})$ Whittaker functions and the Toda lattice. In the index zero case the arrays are reverse plane partitions. We show that this Markov chain has non-trivial Markovian projections and a unique entrance law starting from the array with all entries equal to $+\infty$. We also discuss connections with imaginary exponential functionals of Brownian motion, a semi-discrete polymer model with purely imaginary disorder, interacting corner growth processes and discrete $δ$-Bose gas, extensions to other root systems, and hitting probabilities for some low rank examples.
GIB: Imperfect Information in a Computationally Challenging Game
Creators: name: Ginsberg, M. L.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: This paper investigates the problems arising in the construction of a program to play the game of contract bridge. These problems include both the difficulty of solving the game's perfect information variant, and techniques needed to address the fact that bridge is not, in fact, a perfect information game. GIB, the program being described, involves five separate technical advances: partition search, the practical application of Monte Carlo techniques to realistic problems, a focus on achievable sets to solve problems inherent in the Monte Carlo approach, an extension of alpha-beta pruning from total orders to arbitrary distributive lattices, and the use of squeaky wheel optimization to find approximately optimal solutions to cardplay problems. GIB is currently believed to be of approximately expert caliber, and is currently the strongest computer bridge program in the world.