cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Giant Tunable Mechanical Nonlinearity in Graphene-Silicon Nitride Hybrid Resonator
Creators: name: Singh, Rajan
name: Sarkar, Arnab
name: Guria, Chitres
name: Nicholl, Ryan J. T.
name: Chakraborty, Sagar
name: Bolotin, Kirill I.
name: Ghosh, Saikat
Publisher: name: arXiv
Year: 2019
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: High quality factor mechanical resonators have shown great promise in developing classical or quantum technologies. Simultaneously, progress has been made in developing controlled mechanical nonlinearity. Here we combine these two directions of progress in a single platform consisting of coupled Silicon Nitride (SiNx) and graphene mechanical resonators. We show that nonlinear response can be induced on a large area SiNx resonator mode and can be efficiently controlled by coupling it to a gate-tunable, freely suspended graphene mode. The induced nonlinear response of the hybrid modes, as measured on the SiNx resonator surface is giant, with one of the highest measured Duffing constants. We observe a novel phononic frequency comb which we use as an alternate validation of the measured values, along with numerical simulations which are in overall agreement with measurements.
Coherent states, line bundles and divisors
Creators: name: Berceanu, Stefan
Publisher: name: arXiv
Year: 1998
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 81R30

description: For homogeneous simply connected Hodge manifolds it is proved that the set of coherent vectors orthogonal to a given one is the divisor responsible for the homogeneous holomorphic line bundle of the coherent vectors. In particular, for naturally reductive spaces, the divisor is the cut locus.
description: 8 pages, latex2e, ams fonts, to appear in "Coherent States, Differential and Quantum Geometry", Edited by S. T. Ali, M. Schlichenmaier, A. Strasburger, Proceedings of the XVI Workshop on Geometric Methods in Physics, Bialowieza, Poland, June 30 - July 6, 1997, Rep. Math. Phys
Classification of Petrov Homogeneous Spaces
Creators: name: Obukhov, V. V.
Publisher: name: arXiv
Year: 2024
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences
subject: 70H33 70G65, 83C10

description: In this paper the final stage of the Petrov classification is carried out. As it is known, the Killing vector fields specify infinitesimal transformations of the group of motions of space $V_4$. In the case when in the homogeneous space $V_4$ the group of motions $G_3$ acts simply transitive, the geometry of the non-isotropic hypersurface is determined by the geometry of the transitivity space $V_3$ of the group $G_3$. In this case, the metric tensor of the space $V_3$ can be given by a nonholonomic reper consisting of three independent vectors $\ell_{(a)}^α$, which define the generators of the group $G_3$ of finite transformations in the space $V_3$. The representation of the metric tensor of $V_4$ spaces by means of vector fields $\ell_{(a)}^α$ has a great physical meaning and allows to simplify substantially the equations of mathematical physics in such spaces. Therefore, the Petrov classification should be complemented by the classification of vector fields $\ell_{(a)}^α$ connected to Killing vector fields. For homogeneous spaces this problem has been largely solved. A complete solution of this problem is presented in the present paper, where the Petrov classification for homogeneous spaces in which the group $G_3$, which belongs to type $VIII$ according to the Petrov classification, acts simply transitively, is refined. In addition, the complete classification of vector fields $\ell_{(a)}^α$ for spaces $V_4$ in which the group $G_3$ acts simply transitivity on isotropic hypersurfaces.}
description: 34 pages
title: N.A.E. "spinning" model scale 1/24
title: N.A.E. spinning model C-105 aircraft
titleType: AlternativeTitle
Creators: name: Crowe, L. J.
Publisher: name: A.V. Roe Canada Limited. Engineering Division. Initial Projects Office
Year: 1953
Subjects: subject: Avro Arrow
subject: Avro Arrow
subject: Avro Canada
subject: A.V. Roe Canada
subject: Avro Canada CF-105 Arrow
subject: CF-105
subject: Canada supersonic jet
subject: avion à réaction supersonique du Canada
subject: delta-winged supersonic interceptor
subject: intercepteur supersonique à ailes delta
subject: design and construction
subject: conception et construction

description: Distributed online by the National Research Council of Canada
description: Distribué en ligne par le Conseil national de recherches du Canada
Fixed points and selections of multifunctions on spaces with convexity
Creators: name: Saveliev, Peter
Publisher: name: arXiv
Year: 1999
Subjects: subject: Functional Analysis (math.FA)
subject: General Topology (math.GN)
subject: FOS: Mathematics
subject: 47H04, 47H10, 52A01, 54C65, 54H25

description: We provide theorems containnig both Kakutani and Browder fixed points theorems as immediate corollaries, as well as Michael and Browder selection theorems. For this purpose we introduce convex structures more general than those of locally convex and non-locally convex topological vector spaces or generalized convexity structures due to Michael, Van de Vel and Horvath.
description: 17 pages
title: N.A.E. "low speed" model full span scale .07
Creators: name: Crowe, L. J.
Publisher: name: A.V. Roe Canada Limited. Engineering Division. Initial Projects Office
Year: 1953
Subjects: subject: Avro Arrow
subject: Avro Arrow
subject: Avro Canada
subject: A.V. Roe Canada
subject: Avro Canada CF-105 Arrow
subject: CF-105
subject: Canada supersonic jet
subject: avion à réaction supersonique du Canada
subject: delta-winged supersonic interceptor
subject: intercepteur supersonique à ailes delta
subject: design and construction
subject: conception et construction

description: Distributed online by the National Research Council of Canada
description: Distribué en ligne par le Conseil national de recherches du Canada
Bulk-Free Topological Insulator Bi2Se3 nanoribbons with Magnetotransport Signatures of Dirac Surface States
Creators: name: Kunakova, Gunta
name: Galletti, Luca
name: Charpentier, Sophie
name: Andzane, Jana
name: Erts, Donats
name: Leonard, Francois
name: Spataru, Catalin D.
name: Bauch, Thilo
name: Lombardi, Floriana
Publisher: name: arXiv
Year: 2019
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Many applications for topological insulators (TIs) as well as new phenomena require devices with reduced dimensions. While much progress has been made to realize thin films of TIs with low bulk carrier density, nanostructures have not yet been reported with similar properties, despite the fact that size confinement should help reduce contributions from bulk carriers. Here we demonstrate that Bi2Se3 nanoribbons, grown by a simple catalyst-free physical-vapour deposition, have inherently low bulk carrier densities, and can be further made bulk-free by size confinement, thus revealing the high mobility topological surface states. Magneto transport and Hall conductance measurements, in single nanoribbons, show that at thicknesses below 30nm the bulk transport is completely suppressed which is supported by self-consistent band-bending calculations. The results highlight the importance of material growth and geometrical confinement to properly exploit the unique properties of the topological surface states.
Penalizing fractional Brownian motion for being negative
Creators: name: Aurzada, Frank
name: Buck, Micha
name: Kilian, Martin
Publisher: name: arXiv
Year: 2019
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60G22, 60G10

description: We study a modification of the fractional analogue of the Brownian meander, which is Brownian motion conditioned to be positive on the time interval ${[0,1]}$. More precisely, we determine the weak limit of a fractional Brownian motion which is penalized -- instead of being killed -- when leaving the positive half-axis. In the Brownian case, we give a representation of the limiting process in terms of an explicit SDE and compare it to the SDE fulfilled by the Brownian meander.
description: Minor corrections
Recurrent microblazar activity in Cygnus X-1?
Creators: name: Romero, G. E.
name: Bernado, M. M. Kaufman
name: Mirabel, I. F.
Publisher: name: arXiv
Year: 2002
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Recurrent flaring events at X- and soft gamma-ray energies have been recently reported for the galactic black hole candidate Cygnus X-1. The observed fluxes during these transient outbursts are far higher than what is observed in ``normal'' episodes. Here we suggest that the origin of this radiation is non-thermal and produced by inverse Compton interactions between relativistic electrons in the jet and external photon fields, with a dominant contribution from the companion star field. The recurrent and relatively rapid variability could be explained by the precession of the jet, which results in a variable Doppler amplification.
description: 4 pages, 5 figures, Accepted for publication in Astronomy & Astrophysics Letters
title: Exploring Perspectives on Health among Pasifika Participants from Southeast Queensland: A Qualitative study of Influencing Factors
Creators: name: Faingaa-Manu Sione, Inez H
Publisher: name: Griffith University
Year: 2022
Subjects: subject: Pasifika peoples
subject: health
subject: South East Queensland
subject: preventable illness

description: Pasifika peoples experience disproportionate rates of obesity and diabetes-related conditions that reduce their quality of life and, for many, have resulted in premature death. Unfortunately, Pasifika peoples affected by these preventable life-style diseases have increased in numbers and lowered in age. A set of complex factors appears to influence the health choices of Pasifika peoples, and these need to be better understood. Therefore, this study had three aims: (a) to explore the perspectives of Pasifika peoples from three generations to understand what health means to them, (b) to understand how and why these perspectives influence their health choices, and (c) to identify a response that ensures healthier lives and greater longevity in Pasifika communities. Constructivist grounded theory, Talanoa, and Tongan fala weaving were combined as the methodological approach informing the enquiry involving 29 participants residing in Southeast Queensland. This included individual talanoa with 12 elders representing various Pasifika ethnicities. Gender and age-specific group talanoa also engaged parents and teenagers from one Pasifika church, who were predominantly Samoan. A total of five families participated. The study identified conflicting perspectives regarding the definition of the term “health”, which elders and some parents perceived as a western term focusing specifically on the body and devoid of spirituality. Their preferred term was “wellness”. Factors influencing participants’ health choices included their Christian faith, their commitment to family, their beliefs regarding food, and their quest for prosperity. Strong Pasifika cultural beliefs shaped each factor. Findings informed the development of the Dominant Pasifika Perspectives of Wellness model, which visually captures the interaction of factors influencing health choices. A further finding was that some participants had actively challenged behaviours associated with the dominant Pasifika perspectives of wellness. In doing this, they reported that they had improved their wellness and quality of life. The process they adopted is presented visually in the Alternative Pasifika Perspectives of Wellness model. Both models have utility for informing policy and practical responses to the prevention and management of obesity and diabetes-related conditions within Pasifika communities.
title: N.A.E. "supersonic" model C-105 aircraft full span scale 1/80
Creators: name: Crowe, L. J.
Publisher: name: A.V. Roe Canada Limited. Engineering Division. Initial Projects Office
Year: 1953
Subjects: subject: Avro Arrow
subject: Avro Arrow
subject: Avro Canada
subject: A.V. Roe Canada
subject: Avro Canada CF-105 Arrow
subject: CF-105
subject: Canada supersonic jet
subject: avion à réaction supersonique du Canada
subject: delta-winged supersonic interceptor
subject: intercepteur supersonique à ailes delta
subject: design and construction
subject: conception et construction

description: Distributed online by the National Research Council of Canada
description: Distribué en ligne par le Conseil national de recherches du Canada
title: N.A.E. "supersonic" model C-105 aircraft reflection plane scale .02
Creators: name: Crowe, L. J.
Publisher: name: A.V. Roe Canada Limited. Engineering Division. Initial Projects Office
Year: 1953
Subjects: subject: Avro Arrow
subject: Avro Arrow
subject: Avro Canada
subject: A.V. Roe Canada
subject: Avro Canada CF-105 Arrow
subject: CF-105
subject: Canada supersonic jet
subject: avion à réaction supersonique du Canada
subject: delta-winged supersonic interceptor
subject: intercepteur supersonique à ailes delta
subject: design and construction
subject: conception et construction

description: Distributed online by the National Research Council of Canada
description: Distribué en ligne par le Conseil national de recherches du Canada
title: CF-105 free flight stability model results
Creators: name: Jenkins, M. V.
Publisher: name: Avro Aircraft Limited (Canada). Technical Department
Year: 1957
Subjects: subject: Avro Arrow
subject: Avro Arrow
subject: Avro Canada
subject: A.V. Roe Canada
subject: Avro Canada CF-105 Arrow
subject: CF-105
subject: Canada supersonic jet
subject: avion à réaction supersonique du Canada
subject: delta-winged supersonic interceptor
subject: intercepteur supersonique à ailes delta

description: Distributed online by the National Research Council of Canada
description: Distribué en ligne par le Conseil national de recherches du Canada
title: C-105 Summary of free flight model tests 7 results (F.F.M. #1 to F.F.M. #7)
Creators: name: Ewart, D.
name: Taylor, W.
Publisher: name: Avro Aircraft Limited (Canada). Technical Department
Year: 1957
Subjects: subject: Avro Arrow
subject: Avro Arrow
subject: Avro Canada
subject: A.V. Roe Canada
subject: Avro Canada CF-105 Arrow
subject: CF-105
subject: Canada supersonic jet
subject: avion à réaction supersonique du Canada
subject: delta-winged supersonic interceptor
subject: intercepteur supersonique à ailes delta

description: Distributed online by the National Research Council of Canada
description: Distribué en ligne par le Conseil national de recherches du Canada
Improved cohesin HiChIP protocol and bioinformatic analysis for robust detection of chromatin loops and stripes
Creators: name: Jodkowska, Karolina
name: Parteka-Tojek, Zofia
name: Agarwal, Abhishek
name: Denkiewicz, Michał
name: Korsak, Sevastianos
name: Chiliński, Mateusz
name: Banecki, Krzysztof
name: Plewczynski, Dariusz
Publisher: name: Zenodo
Year: 2024
Subjects: Chromatin Conformation Capture
Cohesin
HiChIP
loop extrusion
stripes
3D chromatin structure
chromatin interactions
chromatin cross-linking

description: Chromosome Conformation Capture (3C) methods, including Hi-C (a high-throughput variation of 3C), detect pairwise interactions between DNA regions, enabling the reconstruction of chromatin architecture in the nucleus. HiChIP is a modification of the Hi-C experiment, which includes a chromatin immunoprecipitation step (ChIP), allowing genome-wide identification of chromatin contacts mediated by a protein of interest. In mammalian cells, cohesin protein complex is one of the major players in the establishment of chromatin loops. We present an improved cohesin HiChIP experimental protocol. Using comprehensive bioinformatic analysis, we show that performing cohesin HiChIP with two cross-linking agents (formaldehyde [FA] and EGS) instead of the typically used FA alone, results in a substantially better signal-to-noise ratio, higher ChIP efficiency and improved detection of chromatin loops and architectural stripes. Additionally, we propose an automated pipeline called nf-HiChIP (https://github.com/SFGLab/hichip-nf-pipeline) for processing HiChIP samples starting from raw sequencing reads data and ending with a set of significant chromatin interactions (loops), which allows efficient and timely analysis of multiple samples in parallel, without the need of additional ChIP-seq experiments. Finally, using novel approaches for biophysical modelling and stripe calling we generate accurate loop extrusion polymer models for a region of interest and a detailed picture of architectural stripes, respectively.
description: Corresponding authors:

d.plewczynski@cent.uw.edu.pl; k.jodkowska@cent.uw.edu.pl
Additional file 1 of Endocervical curettage for diagnosing high-grade squamous intraepithelial lesions or worse in women with type 3 transformation zone lesions: a retrospective, observational study
Creators: name: Wei, Bingrui
name: Li, Qing
name: Seery, Samuel
name: Qiao, Youlin
name: Jiang, Yu
Publisher: name: figshare
Year: 2023
Subjects: subject: Medicine
subject: Biotechnology
subject: Biological Sciences not elsewhere classified
subject: Mathematical Sciences not elsewhere classified
subject: Cancer
subject: Infectious Diseases
subject: FOS: Health sciences

description: Additional file 1:
Group Chat Ecology in Enterprise Instant Messaging: How Employees Collaborate Through Multi-User Chat Channels on Slack
Creators: name: Wang, Dakuo
name: Wang, Haoyu
name: Yu, Mo
name: Ashktorab, Zahra
name: Tan, Ming
Publisher: name: arXiv
Year: 2019
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Despite the long history of studying instant messaging usage, we know very little about how today's people participate in group chat channels and interact with others inside a real-world organization. In this short paper, we aim to update the existing knowledge on how group chat is used in the context of today's organizations. The knowledge is particularly important for the new norm of remote works under the COVID-19 pandemic. We have the privilege of collecting two valuable datasets: a total of 4,300 group chat channels in Slack from an R&D department in a multinational IT company; and a total of 117 groups' performance data. Through qualitative coding of 100 randomly sampled group channels from the 4,300 channels dataset, we identified and reported 9 categories such as Project channels, IT-Support channels, and Event channels. We further defined a feature metric with 21 meta features (and their derived features) without looking at the message content to depict the group communication style for these group chat channels, with which we successfully trained a machine learning model that can automatically classify a given group channel into one of the 9 categories. In addition to the descriptive data analysis, we illustrated how these communication metrics can be used to analyze team performance. We cross-referenced 117 project teams and their team-based Slack channels and identified 57 teams that appeared in both datasets, then we built a regression model to reveal the relationship between these group communication styles and the project team performance. This work contributes an updated empirical understanding of human-human communication practices within the enterprise setting, and suggests design opportunities for the future of human-AI communication experience.
description: Accepted at ACM CSCW'22
Lanurgus capensis Schedl 1965
Creators: name: Jordal, Bjarte H.
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Curculionidae
Lanurgus
Lanurgus capensis

description: Lanurgus capensis Schedl, 1965
(Figs 24, 26, 29)
 Type material. Male, holotype: [South Africa] Cape Province, Alexandria, IO. XI.1961, ex. Ochna arborea, J. S. Taylor [TMSA]. Paratype male, Ac. P.F. 733 [NHMW].
 Diagnosis, male. Length 1.1–1.2 mm, 2.4–2.5 × as long as wide, colour black. Scapus as long as broad, as broad as pedicel, with few seta as long as scapus; antennal club with two bisinuate sutures on basal half; elytral interstriae with spatulate setae in rows except confused on interstriae 8–9; protibiae with three apical denticles. Female unknown.
 Distribution. South Africa.
 Biology. This species is known to breed in Cape Plane, Ochna arborea (Ochnaceae).
 Remarks. The type series consist of males only, characterised by four small tubercles along the anterior margin of the pronotum and the small rounded scapus with few short setae. Patterns in interstrial setae and sutures in the antennal club indicate some affiliation to Pseudolanurgus Jordal, 2021. However, characters otherwise defining that genus is not observed in this species: the apical ventrite is not truncated, the elytral apex not lightly inflated, and some interstriae has multiple confused rows of erect setae.
description: Published as part of Jordal, Bjarte H., 2021, The mainly South African genus Lanurgus revised (Coleoptera, Scolytinae), pp. 87-106 in Zootaxa 5027 (1) on page 97, DOI: 10.11646/zootaxa.5027.1.4, http://zenodo.org/record/5448108
title: Summary of firings of free flight models 3, 4 and 5, May and June 1955
Creators: name: Taylor, W.
Publisher: name: Avro Aircraft Limited (Canada). Technical Department
Year: 1955
Subjects: subject: Avro Arrow
subject: Avro Arrow
subject: Avro Canada
subject: A.V. Roe Canada
subject: Avro Canada CF-105 Arrow
subject: CF-105
subject: Canada supersonic jet
subject: avion à réaction supersonique du Canada
subject: delta-winged supersonic interceptor
subject: intercepteur supersonique à ailes delta

description: Distributed online by the National Research Council of Canada
description: Distribué en ligne par le Conseil national de recherches du Canada
Exact Potts Model Partition Function on Strips of the Triangular Lattice
Creators: name: Chang, Shu-Chiuan
name: Shrock, Robert
Publisher: name: arXiv
Year: 2000
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Lattice (hep-lat)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: In this paper we present exact calculations of the partition function $Z$ of the $q$-state Potts model and its generalization to real $q$, for arbitrary temperature on $n$-vertex strip graphs, of width $L_y=2$ and arbitrary length, of the triangular lattice with free, cyclic, and Möbius longitudinal boundary conditions. These partition functions are equivalent to Tutte/Whitney polynomials for these graphs. The free energy is calculated exactly for the infinite-length limit of the graphs, and the thermodynamics is discussed. Considering the full generalization to arbitrary complex $q$ and temperature, we determine the singular locus ${\cal B}$ in the corresponding ${\mathbb C}^2$ space, arising as the accumulation set of partition function zeros as $n \to \infty$. In particular, we study the connection with the T=0 limit of the Potts antiferromagnet where ${\cal B}$ reduces to the accumulation set of chromatic zeros. Comparisons are made with our previous exact calculation of Potts model partition functions for the corresponding strips of the square lattice. Our present calculations yield, as special cases, several quantities of graph-theoretic interest.
description: 43 pages, latex, 24 postscript figures, Physica A, in press
Properties of Krylov state complexity in qubit dynamics
Creators: name: Seetharaman, Siddharth
name: Singh, Chetanya
name: Nath, Rejish
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We analyze the properties of Krylov state complexity in qubit dynamics, considering a single qubit and a qubit pair. A geometrical picture of the Krylov complexity is discussed for the single-qubit case, whereas it becomes non-trivial for the two-qubit case. Considering the particular case of interacting Rydberg two-level atoms, we show that the Krylov basis obtained using an effective Hamiltonian minimizes the time-averaged spread complexity compared to that which is obtained from the original Hamiltonian. We further generalize the latter property to an arbitrary Hamiltonian in which the entire Hilbert space comprises of two subspaces provided a weak coupling between them.
description: 15 pages, 10 figures
ANALYSIS ON CHARACTERISTICS OF DRILLING FLUIDS INVADING INTO GAS HYDRATES-BEARING FORMATION
Creators: name: Ning, Fulong
name: Jiang, Guosheng
name: Zhang, Ling
name: Bin, Dou
name: Xiang, Wu
Publisher: name: The University of British Columbia
Year: 2008

description: Formations containing gas hydrates are encountered both during ocean drilling for oil or gas, as well as gas hydrate exploration and exploitation. Because the formations are usually permeable porous media, inevitably there are energy and mass exchanges between the water-based drilling fluids and gas hydrates-bearing formation during drilling, which will affect the borehole’s stability and safety. The energy exchange is mainly heat transfer and gas hydrate dissociation as result of it. The gas hydrates around the borehole will be heated to decomposition when the drilling fluids’ temperature is higher than the gas hydrates-bearing formation in situ. while mass exchange is mainly displacement invasion. In conditions of close-balanced or over-balanced drilling, the interaction between drilling fluids and hydrate-bearing formation mainly embodies the invasion of drilling fluids induced by pressure difference and hydrate dissociation induced by heat conduction resulting from differential temperatures. Actually the invasion process is a coupling process of hydrate dissociation, heat conduction and fluid displacement. They interact with each other and influence the parameters of formation surrounding the borehole such as intrinsic mechanics, pore pressure, capillary pressure, water and gas saturation, wave velocity and resistivity. Therefore, the characteristics of the drilling fluids invading into the hydrate-bearing formation and its influence rule should be thoroughly understood when analyzing on wellbore stability, well logging response and formation damage evaluation of hydrate-bearing formation. It can be realized by establishing numerical model of invasion coupled with hydrate dissociation. On the assumption that hydrate is a portion of pore fluids and its dissociation is a continuous water and gas source with no uniform strength, a basic mathematical model is built and can be used to describe the dynamic process of drilling fluids invasion by coupling Kamath’s kinetic equation of heated hydrate dissociation into mass conservation equations.
title: Professionalisierung im Schülerlabor
title: Praxisseminare in der Lehrerbildung
titleType: Subtitle
Creators: name: Krofta, Helen
name: Fandrich, Jörg
name: Nordmeier, Volkhard
Publisher: name: Freie Universität Berlin
Year: 2012
Subjects: subject: 500 Naturwissenschaften und Mathematik::530 Physik

description: In der Literatur wird vielfach ein Praxisschock beschrieben, den angehende LehrerInnen beim Übergang vom Studium in das Referendariat erleben [1, 2]. Daher wird vielfach gefordert, im Stu-dium mehr praktische Erfahrungen zu ermöglichen. Untersuchungen zeigen jedoch auch, dass die-se nur dann zur Verbesserung der Lehrerausbildung beitragen, wenn sie theoretisch fundiert und didaktisch reflektiert werden [3]. Unreflektierte Praxisphasen wie z.B. nicht begleitete Schulprak-tika können im ungünstigen Fall sogar zu einer Deprofessionalisierung führen, verbunden mit ei-ner Abkehr von einer theoriegeleiteten Fundierung didaktisch-pädagogischer Entscheidungen [4, 5]. Im Projekt „MINT-Lehrerbildung neu denken!” werden an der Freien Universität Berlin die Pra-xisphasen im Lehramtsstudium durch neu eingerichtete Praxisseminare ausgebaut [6]. In diesen Seminaren entwickeln Lehramtsstudierende der Physik im Schülerlabor PhysLab eigene Unter- richtskonzepte und erproben sie mit Schulklassen. Weitere Praxisseminare für Lehramtsstudieren-de anderer Fächer werden in den Partnerlaboren NatLab (Chemie, Biologie) und MI.Lab (Mathe-matik, Informatik) angeboten. Ein Schülerlabor bietet vielschichtige Ressourcen als Lernort für Studierende. Es ermöglicht beispielsweise zusätzliche Freiheitsgrade bei der Wahl der Themen, Methoden oder Materialien und stellt eine ‚geschützte’ Umgebung zur Erprobung neuer Unter-richtskonzepte dar. Durch die Praxisseminare im Schülerlabor soll insbesondere die Kompetenzentwicklung der Stu-dierenden in den Bereichen Fachwissen, fachdidaktisches und pädagogisches Wissen unterstützt werden sowie eine forschend-reflexive Haltung durch Planung, Durchführung und Beobachtung von Unterricht mit anschließender Reflexion der Lehr-Lern-Prozesse gefördert werden. Im Rahmen einer Begleitstudie wird untersucht, inwieweit sich das entwickelte Konzept der Pra-xisseminare eignet, die Professionalisierung von Lehramtsstudierenden zu unterstützen und damit einen Beitrag zur Verbesserung der Lehrerbildung zu leisten. Das Konzept des Praxisseminars Wärmeübertragung wurde bereits ausführlich vorgestellt [6]. In diesem Beitrag soll nun der Ansatz der Begleitforschung zur Wirksamkeitsüberprüfung der Praxis-seminare vorgestellt werden.
title: Summary of firings of free flight models 1 and 2 week commencing December 12th 1954
Creators: name: Taylor, W.
Publisher: name: Avro Aircraft Limited (Canada). Technical Department
Year: 1955
Subjects: subject: Avro Arrow
subject: Avro Arrow
subject: Avro Canada
subject: A.V. Roe Canada
subject: Avro Canada CF-105 Arrow
subject: CF-105
subject: Canada supersonic jet
subject: avion à réaction supersonique du Canada
subject: delta-winged supersonic interceptor
subject: intercepteur supersonique à ailes delta

description: Distributed online by the National Research Council of Canada
description: Distribué en ligne par le Conseil national de recherches du Canada
Curvature as an integrable deformation
Creators: name: Ballesteros, Angel
name: Blasco, Alfonso
name: Herranz, Francisco J.
Publisher: name: arXiv
Year: 2019
Subjects: subject: Mathematical Physics (math-ph)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences
subject: 37J35, 70H06, 22E60

description: The generalization of (super)integrable Euclidean classical Hamiltonian systems to the two-dimensional sphere and the hyperbolic space by preserving their (super)integrability properties is reviewed. The constant Gaussian curvature of the underlying spaces is introduced as an explicit deformation parameter, thus allowing the construction of new integrable Hamiltonians in a unified geometric setting in which the Euclidean systems are obtained in the vanishing curvature limit. In particular, the constant curvature analogue of the generic anisotropic oscillator Hamiltonian is presented, and its superintegrability for commensurate frequencies is shown. As a second example, an integrable version of the Hénon-Heiles system on the sphere and the hyperbolic plane is introduced. Projective Beltrami coordinates are shown to be helpful in this construction, and further applications of this approach are sketched
description: 34 pages, 1 figure. To appear in "Integrability, Supersymmetry and Coherent States", A volume in honour of Professor V\'eronique Hussin. S. Kuru, J. Negro and L.M. Nieto (Eds.), Special volume of the CRM Series in Mathematical Physics (Berlin: Springer, 2019)
Effect of Complete Streets Infrastructure and Design on Street Life
Creators: Young, Taylor
Publisher: name: Columbia University
Year: 2017
Subjects: Streets--Design and construction
Streetscapes (Urban design)
Bicycle lanes
City planning

description: Complete streets policies are spreading throughout the United States, and this thesis explores their provides greater understanding of how complete streets style designs impact street life. Research for the thesis includes observations of street life at four locations with complete streets designs as well as interviews with residents, community advocates, municipal planners, and other project stakeholders. Observational research provides examples of how people interact in a complete streets environment, compared with control sites within the same neighborhood. This thesis found that complete streets style infrastructure effects street life through improved street safety, creating a welcoming environment and sense of place, and through economic development. The study of four street redesigns and interviews with project designers reveal implementation patterns and which parts of the street redesign were most effective in achieving their goals. The thesis concludes with a critique of complete streets design and implementation, yet proposes that they should be created where possible due to their positive impacts on safety for the most vulnerable street users.
Effect of Local Context on Flood Vulnerability Identification: A comparison between New Orleans’ flood vulnerability assessment tools and globally applicable vulnerability indices
Creators: Khan, Maira
Publisher: name: Columbia University
Year: 2017
Subjects: City planning
Flood control
Flood control--Planning
Floods
Emergency management
Natural disasters--Planning

description: Flood occurrences are on the increase all over the world and large numbers of people are constantly exposed to the risk associated with these disasters. Vulnerability assessment is integral to flood risk management. It helps identify areas with high flood risk and guides resilience policies. Vulnerability, being an intangible notion, is difficult to assess. Many municipalities resort to field-survey and community outreach based assessment processes. These tools are sensitive to local context, but are time and resource intensive. Consequently, many municipalities with limited resources, especially those in developing countries, cannot adopt this methodology. Moreover, this tool is susceptible to political biases and corruption. Another widely used assessment method is indicator-based, which involves developing Flood Vulnerability Indices (FVIs) by using available data to provide a logical image of a region's vulnerability to disaster. The quantitative nature of this tool makes it quicker, cost effective, and objective. But this attempt to measure a qualitative concept like vulnerability exposes these indices to statistical fallacies, leading to inadequate results. Moreover, these one-size-fits-all indices fail to acknowledge the distinct characteristics of a society.
   This study aims to investigate the effectiveness of FVIs and find out if their quantitative nature, by ignoring the intangible local characteristics of society, compromises the credibility of outcomes derived. Purpose is to learn if these indices can provide with adequate understanding of vulnerability in areas where governments either don’t have the time and capital to invest in extensive field surveys, or are plagued by corruption. As a case study, this thesis examines the application of Bathi and Das’ flood vulnerability index on New Orleans’ socio-economic and environmental data and compares the results to those of assessment methods developed by the city of New Orleans. This helps understand how flood risk identification through local tools differs from FVIs, and the extent to which this influences the flood mitigation and adaptation policies made. The research concludes with recommendations to statistically improve FVIs and, when necessary, use a combination of local knowledge based qualitative techniques and FVIs to get adequate results, in turn making better informed decisions when devising flood resilience policies.
Structure of the Hantavirus Nucleoprotein Provides Insights into the Mechanism of RNA Encapsidation
Creators: name: Olal, Daniel
name: Daumke, Oliver
Publisher: name: Freie Universität Berlin
Year: 2016
Subjects: subject: 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::572 Biochemie

description: Hantaviruses are etiological agents of life-threatening hemorrhagic fever with renal syndrome and hantavirus cardiopulmonary syndrome. The nucleoprotein (N) of hantavirus is essential for viral transcription and replication, thus representing an attractive target for therapeutic intervention. We have determined the crystal structure of hantavirus N to 3.2 Å resolution. The structure reveals a two-lobed, mostly α-helical structure that is distantly related to that of orthobunyavirus Ns. A basic RNA binding pocket is located at the intersection between the two lobes. We provide evidence that oligomerization is mediated by amino- and C-terminal arms that bind to the adjacent monomers. Based on these findings, we suggest a model for the oligomeric ribonucleoprotein (RNP) complex. Our structure provides mechanistic insights into RNA encapsidation in the genus Hantavirus and constitutes a template for drug discovery efforts aimed at combating hantavirus infections.
Unabsorbed Seyfert 2 galaxies
Creators: name: Panessa, Francesca
name: Bassani, Loredana
Publisher: name: arXiv
Year: 2002
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present a sample of 17 type 2 Seyfert galaxies which have an X-ray column density lower than 10^{22} cm^{-2}. The Compton thin nature of these sources is strongly suggested by isotropic indicators. We estimate the fraction of these sources to be in the range of 10% - 30% of the population of type 2 Seyfert galaxies. Furthermore, this fraction appears to increase progressively at lower luminosities. The simple formulation of the Unified Model for Seyfert galaxies is not applicable in such sources since the pc-scale molecular torus is not likely to be responsible for the low column density observed, instead the absorption observed is likely to originate at larger scales. According to this hypothesis, in these objects the broad line regions are covered by some dusty obscuring material. In particular, this could occur in objects with dust lanes, patches or HII regions. However, we cannot rule out that in the lowest luminosity sources the BLR is weak, absent or has faded away. This last scenario is consistent with the predictions of some recent theoretical models for low luminosity AGNs.
description: 9 pages, 5 figures. Accepted for publication in A&A
Combinatorics in the exterior algebra and the Bollobás Two Families Theorem
Creators: name: Scott, Alex
name: Wilmer, Elizabeth
Publisher: name: arXiv
Year: 2019
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05D05 (Primary) 15A75, 14N20 (Secondary)

description: We investigate the combinatorial structure of subspaces of the exterior algebra of a finite-dimensional real vector space, working in parallel with the extremal combinatorics of hypergraphs. Using initial monomials, projections of the underlying vector space onto subspaces, and the interior product, we find analogues of local and global LYM inequalities, the Erdős-Ko-Rado theorem, and the Ahlswede-Khachatrian bound for $t$-intersecting hypergraphs. Using these tools, we prove a new extension of the Two Families Theorem of Bollobás, giving a weighted bound for subspace configurations satisfying a skew cross-intersection condition. We also verify a recent conjecture of Gerbner, Keszegh, Methuku, Abhishek, Nagy, Patkós, Tompkins, and Xiao on pairs of set systems satisfying both an intersection and a cross-intersection condition.
description: 29 pages, substantial revision: new results in sections 2.5 (exterior downwards local LYM), 2.6 (exterior Ahslwede-Khachatrian bound), and 5 (proof of a conjecture of Gerbner et al, arxiv:1910.04666[math.CO])
THE GAS HYDRATE PROCESS FOR SEPARATION OF CO2 FROM FUEL GAS MIXTURE: MACRO AND MOLECULAR LEVEL STUDIES
Creators: name: Ripmeester, John A.
name: Englezos, Peter
name: Kumar, Rajnish
Publisher: name: The University of British Columbia
Year: 2008

description: The “Integrated Coal Gasification Combined Cycle” (IGCC) represents an advanced approach for green field projects for power generation. This process requires separation of carbon dioxide from the shifted-synthesis gas mixture (fuel gas). Treated fuel gas consists of approximately 40% CO2 and rest H2. Gas hydrate based separation technology for hydrate forming gas mixtures is one of the novel approaches for gas separation. The present study illustrates the gas hydrate-based separation process for the recovery of CO2 and H2 from the fuel gas mixture and discusses relevant issues from macro and molecular level perspectives. Propane (C3H8) is used as an additive to reduce the operating pressure for hydrate formation and hence the compression costs. Based on gas uptake measurement during hydrate formation, a hybrid conceptual process for pre-combustion capture of CO2 is presented. The result shows that it is possible to separate CO2 from hydrogen and obtain a hydrate phase with 98% CO2 in two stages starting from a mixture of 39.2% CO2. Molecular level work has also been performed on CO2/H2 and CO2/H2/C3H8 systems to understand the mechanism by which propane reduces the operating pressure without compromising the separation efficiency.
Effect of Surface Curvature and Chemistry on Protein Stability, Adsorption and Aggregation
Creators: Radhakrishna, Mithun
Publisher: name: Columbia University
Year: 2014
Subjects: subject: Chemical engineering
subject: FOS: Chemical engineering
subject: Condensed matter

description: Enzyme immobilization has been of great industrial importance because of its use in various applications like bio-fuel cells, bio-sensors, drug delivery and bio-catalytic films. Although research on enzyme immobilization dates back to the 1970's, it has been only in the past decade that scientists have started to address the problems involved systematically. Most of the previous works on enzyme immobilization have been retrospective in nature i.e enzymes were immobilized on widely used substrates without a compatibility study between the enzyme and the substrate. Consequently, most of the enzymes lost their activity upon immobilization onto these substrates due to many governing factors like protein-surface and inter-protein interactions. These interactions also play a major role biologically in cell signaling, cell adhesion and inter-protein interactions specifically is believed to be the major cause for neurodegenerative diseases like Alzheimer's and Parkinson's disease. Therefore understanding the role of these forces on proteins is the need of the hour. In my current research, I have mainly focused on two factors a) Surface Curvature b) Surface Chemistry as both of these play a pivotal role in influencing the activity of the enzymes upon immobilization. I study the effect of these factors computationally using a stochastic method known as Monte Carlo simulations.
      My research work carried out in the frame work of a Hydrophobic-Polar (HP) lattice model for the protein shows that immobilizing enzymes inside moderately hydrophilic or hydrophobic pores results in an enhancement of the enzymatic activity compared to that in the bulk. Our results also indicate that there is an optimal value of surface curvature and hydrophobicity/hydrophilicity where this enhancement of enzymatic activity is highest. Further, our results also show that immobilization of enzymes inside hydrophobic pores of optimal sizes are most effective in mitigating protein-aggregation. These results provide us a rationale to understand the role of chaperonins in protein folding and disaggregation. Our results indicate that strong protein-surface interactions and confinement inducement stability inside pores makes it best suitable for enzyme immobilization.
title: Arrow 1. Proposed flight test program: phase 1
Creators: name: Hodge, J. D.
Publisher: name: Avro Aircraft Limited (Canada)
Year: 1958
Subjects: subject: Avro Arrow
subject: Avro Arrow
subject: Avro Canada
subject: A.V. Roe Canada
subject: Avro Canada CF-105 Arrow
subject: CF-105
subject: Canada supersonic jet
subject: avion à réaction supersonique du Canada
subject: delta-winged supersonic interceptor
subject: intercepteur supersonique à ailes delta

description: Distributed online by the National Research Council of Canada
description: Distribué en ligne par le Conseil national de recherches du Canada
Discovery of a very cool object with extraordinarily strong H(alpha) emission
Creators: name: Navascues, David Barrado y
name: Osorio, Maria Rosa Zapatero
name: Martin, Eduardo L.
name: Bejar, Victor J. S.
name: Rebolo, Rafael
name: Mundt, Reinhard
Publisher: name: arXiv
Year: 2002
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We report on the finding of the strongest H(alpha) emission -pseudoequivalent width of 705 Angstrom- known so far in a young, late type dwarf. This object, named as SOri71, is a substellar candidate member of the 1-8 Myr star cluster sigma Orionis. Due to its overluminous location in color-magnitude diagrams, SOri71 might be younger than other cluster members, or a binary of similar components. Its mass is in the range 0.021-0.012 M(sun), depending on evolutionary models and possible binarity. The broad H(alpha) line of SOri71 appears asymmetric, indicative of high velocity mass motions in the H(alpha) forming region. The origin of this emission is unclear at the present time. We discuss three possible scenarios: accretion from a disk, mass exchange between the components of a binary system, and emission from a chromosphere.
description: Astronomy and Astrophysics Letters, accepted
On the number of non-G-equivalent minimal abelian codes
Creators: name: Aksu, Fatma Altunbulak
name: Tuvay, İpek
Publisher: name: arXiv
Year: 2019
Subjects: subject: Group Theory (math.GR)
subject: Information Theory (cs.IT)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: 20K01, 94B05, 16S34

description: Let $G$ be a finite abelian group. Ferraz, Guerreiro and Polcino Milies prove that the number of $G$-equivalence classes of minimal abelian codes is equal to the number of $G$-isomorphism classes of subgroups for which corresponding quotients are cyclic. In this article, we prove that the notion of $G$-isomorphism is equivalent to the notion of isomorphism on the set of all subgroups $H$ of $G$ with the property that $G/H$ is cyclic. As an application, we calculate the number of non-$G$-equivalent minimal abelian codes for some specific family of abelian groups. We also prove that the number of non-$G$-equivalent minimal abelian codes is equal to number of divisors of the exponent of $G$ if and only if for each prime $p$ dividing the order of $G$, the Sylow $p$-subgroups of $G$ are homocyclic.
description: 8 pages
Supplement.pdf from Gaussian process emulation to accelerate parameter estimation in a mechanical model of the left ventricle: a critical step towards clinical end-user relevance
Creators: name: Noè, Umberto
name: Lazarus, Alan
name: Gao, Hao
name: Vinny Davies
name: Macdonald, Benn
name: Mangion, Kenneth
name: Berry, Colin
name: Xiaoyu Luo
name: Husmeier, Dirk
Publisher: name: The Royal Society
Year: 2019
Subjects: subject: Biophysics
subject: Computational Biology
subject: 10202 Biological Mathematics
subject: FOS: Mathematics

description: Additional information on multivariate GPs, global optimization, circumferential strains and the simulation process.