cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Mentha aquatica L. aerial parts: in vitro anti-proliferative evaluation on human tumour and non-tumour cell lines
Creators: name: de Souza, Luciana Bitencourt
name: Tinti, Sirlene Valerio
name: de Oliveira Sousa, Ilza Maria
name: Montanari, Ilio
name: da Costa, José Luiz
name: de Carvalho, João Ernesto
name: Foglio, Mary Ann
name: Ruiz, Ana Lucia Tasca Gois
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Cell Biology
subject: Neuroscience
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Cancer
subject: Hematology

description: Bearing in mind the several medicinal properties of Mentha genus, this work aimed to evaluate the anti-proliferative potential of the ethanolic extract (EE) and fractions from M. aquatica L aerial parts. Using the anti-proliferative protocol developed by the NCI/USA, four fractions (F2 – F4 and F6) obtained from EE showed promising anti-proliferative profile against a panel of human tumor and non-tumor cell lines. After 24-h exposure, F2 (0.25 µg/mL) showed potent and irreversible anti-proliferative effect without inducing cell cycle arrest in both NCI-H460 and MCF-7 cells, without (anti) estrogenic activity. These effects were lost after storage of F2 diluted in dimethyl sulfoxide at −80 °C during 2 weeks. Analysis by gas chromatography coupled to mass detection evidenced some chemical changes induced by F2 storage in solution. The present study demonstrated the anti-proliferative effect of M. aquatica. Further studies are necessary to determine better storage conditions to enhance F2 stability.
Girls Day 2018: Environmental Science
Creators: name: Brindha Muniappan
name: Novotney, Jennifer
Publisher: name: figshare
Year: 2019
Subjects: Environmental Science

description: Girls Days are biannual programs that the Education & Public Programs team at the MIT Museum conceived of, and first produced, in 2013. Each day is focused on a particular STEM topic and has three main components based on the day’s theme: short, snappy career talks by 3-4 women in unusual careers or who had interesting paths to their current profession; 10-15 different “drop-in” hands-on activities offered by local scientists and engineers; a group activity. The student collaborators – all volunteers – were asked to produce an original activity related to their research or studies, that would not likely have already been demonstrated elsewhere. The challenge encouraged our collaborators to consider unique aspects of their work and how it could be interactively explored by non-university audiences. Presenters for the brief career talks were selected for their varied perspectives and careers: an environmental journalist, a graduate student who studies climate change through models of sea-level rise, a post-doctoral archaeologist, and a geology professor. Each was then coached by the authors to prepare a 10-minute presentation. Presenters were asked to limit use of slides but if needed, rely on pictures rather than text or graphs; describe their career paths; encourage participation from the audience; and provide words of advice to young prospective scientists. Some of the activities developed included exploring topological maps, identifying gemstones, comparing ripple patterns in ancient rocks, walking the Gulf Stream on an iGlobe, launching virtual balloons, Weather in a Tank, and a game to learn about pioneering female environmental scientists. For the Girls Day documented in this report, more than 800 visitors took part in the day’s environmental science activities, which were hosted by 70 undergraduate and graduate students from MIT, Harvard, Boston University, and Northeastern University, and ~10 year-round MIT Museum volunteers. Girls Days have proven popular with the target audience (females of age 10+ years) as well as with parents, guardians and chaperones. Attendance has grown since the program was initiated in 2013, with people traveling from the greater Boston area and beyond. Interest from students and researchers in participating has grown as well, with first-time students and researchers asking to participate in future Girls Day programs. The opportunity to share personal interest in STEM fields through creative, hands-on activities has appeal for both participants and presenters. We have varied this mode of engagement in many ways, tailoring programs to particular topics (e.g. VR/AR Day; Mathternoon; Nautical Night) with notable success.
Formation of Ramsey Fringes in Double Bose-Einstein Condensates
Creators: name: Eschmann, A.
name: Ballagh, R. J.
name: Caradoc-Davies, B. M.
Publisher: name: arXiv
Year: 1999
Subjects: subject: Condensed Matter (cond-mat)
subject: FOS: Physical sciences

description: Numerical simulations of Ramsey fringe formation in double Bose condensates are carried out in two spatial dimensions. The effects of meanfield nonlinearity and diffusion in the condensates give rise to new features in the Ramsey fringes, namely spatial variation and an asymmetry between positive and negative field detunings. We introduce the concept of an effective detuning, which for moderate interpulse times provides a qualitative understanding of the new features.
description: 5 pages, including 5 figures. This paper was presented at ACOLS98, and will appear in a special issue of J. Opt. B
Additional file 3 of Circ-GALNT16 restrains colorectal cancer progression by enhancing the SUMOylation of hnRNPK
Creators: name: Peng, Chaofan
name: Tan, Yuqian
name: Yang, Peng
name: Jin, Kangpeng
name: Zhang, Chuan
name: Peng, Wen
name: Wang, Lu
name: Zhou, Jiahui
name: Chen, Ranran
name: Wang, Tuo
name: Jin, Chi
name: Ji, Jiangzhou
name: Feng, Yifei
name: Tang, Junwei
name: Sun, Yueming
Publisher: name: figshare
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences

description: Additional file 3: Figure S3. Circ-GALNT16 stably knockdown and overexpression efficiency, and phenotype assays in vitro and vivo. a. The efficiency of circ-GALNT16 knockdown in DLD-1 and LoVo. The expression of GALNT16 mRNA remained unchangeable. b. The efficiency of circ-GALNT16 overexpression in RKO and HCT 116. The expression of GALNT16 mRNA level was detected at the same time. c. The tumor volumes were measured every 5 days since the subcutaneous tumors were macroscopic. d. Protein levels of Ki67, C-myc, and Serpine1 in the tumor samples were measured by IHC. e. Subcellular fractionation indicated that circ-GALNT16 was predominately localized in the nucleus of CRC cells. All data are presented as the means ± SD of three independent experiments. nsp > 0.05 **p < 0.01, ***p < 0.001.
Subordinators which are infinitely divisible w.r.t. time: Construction, properties, and simulation of max-stable sequences and infinitely divisible laws
Creators: name: Mai, Jan-Frederik
name: Scherer, Matthias
Publisher: name: arXiv
Year: 2018
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: The concept of a Lévy subordinator is generalized to a family of non-decreasing stochastic processes, which are parameterized in terms of two Bernstein functions. Whereas the independent increments property is only maintained in the Lévy subordinator special case, the considered family is always strongly infinitely divisible with respect to time, meaning that a path can be represented in distribution as a finite sum with arbitrarily many summands of independent and identically distributed paths of another process. Besides distributional properties of the process, we present two applications to the design of accurate and efficient simulation algorithms. First, each member of the considered family corresponds uniquely to an exchangeable max-stable sequence of random variables, and we demonstrate how the associated extreme-value copula can be simulated exactly and efficiently from its Pickands dependence measure. Second, we show how one obtains different series and integral representations for infinitely divisible probability laws by varying the parameterizing pair of Bernstein functions, without changing the law of one-dimensional margins of the process. As a particular example, we present an exact simulation algorithm for compound Poisson distributions from the Bondesson class, for which the generalized inverse of the distribution function of the associated Stieltjes measure can be evaluated accurately.
Interplay between Magnetic and Vestigial Nematic Orders in the Layered $J_1$-$J_2$ Classical Heisenberg Model
Creators: name: Syljuåsen, Olav F.
name: Paaske, Jens
name: Schecter, Michael
Publisher: name: arXiv
Year: 2019
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We study the layered $J_1$-$J_2$ classical Heisenberg model on the square lattice using a self-consistent bond theory. We derive the phase diagram for fixed $J_1$ as a function of temperature $T$, $J_2$ and interplane coupling $J_z$. Broad regions of (anti)ferromagnetic and stripe order are found, and are separated by a first-order transition near $J_2\approx 0.5$ (in units of $|J_1|$). Within the stripe phase the magnetic and vestigial nematic transitions occur simultaneously in first-order fashion for strong $J_z$. For weaker $J_z$ there is in addition, for $J_2^*
description: 13 pages, 20 figures
Effects of classroom “flipping” on content mastery and student confidence in an introductory physical geology course
Creators: name: Jones, Jason P.
name: McConnell, David A.
name: Wiggen, Jennifer L.
name: Bedward, John
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biochemistry
subject: Medicine
subject: Sociology
subject: FOS: Sociology
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Science Policy

description: Incorporating active learning strategies into introductory STEM courses has been shown to improve student outcomes, however, these activities take class time to execute. The question of how to implement these effective strategies without sacrificing a significant volume of content coverage has led to the development of a “flipped” model of instruction. This flipped model requires students to take responsibility for learning some basic concepts prior to attending class so the instructor can use newly freed class time to incorporate active learning activities. This study investigated the impact of implementing a partially flipped class format on student exam performance and confidence across four semesters of a large-enrollment physical geology course. Basic geology content was presented as pre-class homework assignments using short instructional videos (Geoscience Videos) that were created following empirically-derived methods of effective multimedia design. The videos facilitated an increase in the proportion of content that could be communicated outside of class and allowed for an augmentation of in-class activities on more complex geology concepts. We compared student performance and confidence across semesters and found; (a) students were able to learn the basic content as effectively as they had when it was presented in class; (b) students improved their performance on some content during summative exams; and, (c) student confidence significantly varied on some topics as a result of the course alterations. As a result, we posit that the flipped model can provide valuable opportunities to increase student learning as long as students are supported via out-of-class homework and feedback on their level of understanding regarding topics they are learning prior to attending course meetings.
The physics of thermal light second-order interference beyond coherence
Creators: name: Tamma, Vincenzo
Publisher: name: arXiv
Year: 2018
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A novel thermal light interferometer was recently introduced in V. Tamma and J. Seiler, New J. Phys. 18, 032002 (2016). Here, two classically correlated beams, obtained by beam splitting a thermal light beam, propagate through two unbalanced Mach-Zehnder interferometers. Remarkably, second-order interference between the long and the short paths in the two interferometers was predicted independently of how far, in principle, the length difference between the long and short paths is beyond the coherence length of the source. This phenomenon seems to contradict our common understanding of second order coherence. We provide here a simple description of the physics underlying this effect in terms of two-photon interference.
description: in honour of Professor Wolfgang P. Schleich on the occasion of his 60th birthday
Unified Quantum Mechanical Picture for Confined Spinons in Dimerized and Frustrated Spin S=1/2 Chains
Creators: name: Uhrig, Goetz S.
name: Schoenfeld, Friedhelm
name: Laukamp, Markus
name: Dagotto, Elbio
Publisher: name: arXiv
Year: 1998
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: A quantum mechanical picture is presented to describe the behavior of confined spinons in a variety of S=1/2 chains. The confinement is due to dimerization and frustration and it manifests itselfas a nonlinear potential V(x)~ |x|^b, centered at chain ends (b <= 1) or produced by modulation kinks (b > 1). The calculation extends to weak or zero frustration some previous ideas valid for spinons in strongly frustrated spin chains. The local magnetization patterns of the confined spinons are calculated. A (minimum) enhancement of the local moments of about 11/3 over a single S=1/2 is found. Estimates for excitation energies and binding lengths are obtained.
description: 11.5 pages, Revtex, 10 figures included, accepted by Euro. Phys. J. B final version including some changes, several references added
Density Matrix Renormalization Group Study of the Haldane Phase in Random One-Dimensional Antiferromagnets
Creators: name: Hida, Kazuo
Publisher: name: arXiv
Year: 1999
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: It is conjectured that the Haldane phase of the S=1 antiferromagnetic Heisenberg chain and the $S=1/2$ ferromagnetic-antiferromagnetic alternating Heisenberg chain is stable against any strength of randomness, because of imposed breakdown of translational symmetry. This conjecture is confirmed by the density matrix renormalization group calculation of the string order parameter and the energy gap distribution.
description: 4 Pages, 7 figures; Considerable revisions are made in abstract and main text. Final accepted version
Emergence of linguistic conventions in multi-agent reinforcement learning
Creators: name: Lipowska, Dorota
name: Lipowski, Adam
Publisher: name: arXiv
Year: 2018
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Computation and Language (cs.CL)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Recently, emergence of signaling conventions, among which language is a prime example, draws a considerable interdisciplinary interest ranging from game theory, to robotics to evolutionary linguistics. Such a wide spectrum of research is based on much different assumptions and methodologies, but complexity of the problem precludes formulation of a unifying and commonly accepted explanation. We examine formation of signaling conventions in a framework of a multi-agent reinforcement learning model. When the network of interactions between agents is a complete graph or a sufficiently dense random graph, a global consensus is typically reached with the emerging language being a nearly unique object-word mapping or containing some synonyms and homonyms. On finite-dimensional lattices, the model gets trapped in disordered configurations with a local consensus only. Such a trapping can be avoided by introducing a population renewal, which in the presence of superlinear reinforcement restores an ordinary surface-tension driven coarsening and considerably enhances formation of efficient signaling.
description: 18 pages, PLOS ONE (accepted)
Acoustic Performance of Micro-Grooved Elements
Creators: name: Auriemma, F.
Publisher: name: arXiv
Year: 2019
Subjects: subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: The acoustic performance of a new type of fibre-less sound absorber, the micro-grooved element (MGE), is studied in this paper. A MGE is a double layer element that involves inlet/outlet slots and inner micro-channels engraved onto the mating surface of the layers. MGEs are potential substitute of traditional micro-perforated elements (MPEs) in applications where the absorption coefficient, the acoustic behaviour at high levels of sound excitation and the cost of the absorber are of main concern. The transfer impedance and the absorption coefficient of MGEs and MPEs are measured, modelled and compared in this study. The acoustics of the micro-channels is treated in detail, the impedance end corrections are determined and the non-linear effects are accounted for. The linear behaviour of MGEs is described by extending the models for slit-shaped perforated elements. The quasi- and non- linear behaviours are expressed as a function of the Shear number and Strouhal number by curve fitting the experimental results.
Effectiveness of Good Dairy Farming Practice (GDFP) Implementation on the Number of Milk Microorganisms in Smallholder Dairy Farms in Malang District
Creators: name: Archie Rama Reyhan, Tri Eko Susilorini, Suyadi
Publisher: name: Zenodo
Year: 2024

description: Good Dairy Framing Practice (GDFP) is a detailed standard guide for dairy farmer practices, to obtain quality-assured and efficient milk. The application of GDFP by smallholder farmers in Malang Regency is not yet known to be effective on milk quality. The purpose of this study was to determine the effectiveness of GDFP implementation by smallholder farmers in Malang Regency on milk quality by measuring the number of microorganisms produced from the farmers' fresh milk. This study used an interview survey method to 100 dairy farmers in Malang Regency and tested milk quality by measuring the number of bacteria using the Total Plate Count (TPC) method. The results showed the value of GDFP implementation in Malang District in Wagir District and Ngajum District with an average rating of 3.65 and 3.45 included in the good category. The application has effectiveness on the quality of milk produced by measuring TPC found the average number of microorganisms 10.54 x 10² CFU/mL and 12.26 x 10² CFU/mL. The status of fresh milk is safe for consumption according to SNI.
Efficient Autotuning of Hyperparameters in Approximate Nearest Neighbor Search
Creators: name: Jääsaari, Elias
name: Hyvönen, Ville
name: Roos, Teemu
Publisher: name: arXiv
Year: 2018
Subjects: subject: Data Structures and Algorithms (cs.DS)
subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Approximate nearest neighbor algorithms are used to speed up nearest neighbor search in a wide array of applications. However, current indexing methods feature several hyperparameters that need to be tuned to reach an acceptable accuracy--speed trade-off. A grid search in the parameter space is often impractically slow due to a time-consuming index-building procedure. Therefore, we propose an algorithm for automatically tuning the hyperparameters of indexing methods based on randomized space-partitioning trees. In particular, we present results using randomized k-d trees, random projection trees and randomized PCA trees. The tuning algorithm adds minimal overhead to the index-building process but is able to find the optimal hyperparameters accurately. We demonstrate that the algorithm is significantly faster than existing approaches, and that the indexing methods used are competitive with the state-of-the-art methods in query time while being faster to build.
description: Accepted for the 23rd Pacific-Asia Conference on Knowledge Discovery and Data Mining (PAKDD) 2019
M Dwarfs from Hubble Space Telescope Star Counts. IV
Creators: name: Zheng, Zheng
name: Flynn, Chris
name: Gould, Andrew
name: Bahcall, John N.
name: Salim, Samir
Publisher: name: arXiv
Year: 2001
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We study a sample of about 1400 disk M dwarfs that are found in 148 fields observed with the Wide Field Camera 2 (WFC2) on the Hubble Space Telescope and 162 fields observed with pre-repair Planetary Camera 1 (PC1), of which 95 of the WFC2 fields are newly analyzed. The method of maximum likelihood is applied to derive the luminosity function and the Galactic disk parameters. At first, we use a local color-magnitude relation and a locally determined mass-luminosity relation in our analysis. The results are consistent with those of previous work but with considerably reduced statistical errors. These small statistical errors motivate us to investigate the systematic uncertainties. Considering the metallicity gradient above the Galactic plane, we introduce a modified color-magnitude relation that is a function of Galactic height. The resultant M dwarf luminosity function has a shape similar to that derived using the local color-magnitude relation but with a higher peak value. The peak occurs at $M_V \sim 12$ and the luminosity function drops sharply toward $M_V \sim 14$. We then apply a height-dependent mass-luminosity function interpolated from theoretical models with different metallicities to calculate the mass function. Unlike the mass function obtained using local relations, which has a power-law index $α= 0.47$, the one derived from the height-dependent relations tends to be flat ($α= -0.10$). The resultant local surface density of disk M dwarfs (12.2 +/- 1.6 M_sun pc^{-2}) is somewhat smaller than the one obtained using local relations (14.3 +/- 1.3 M_sun pc^{-2}). Our measurement favors a short disk scale length, H = 2.75 +/- 0.16 (statistical) +/- 0.25 (systematic) kpc.
description: 20 pages, 10 ps figures, accepted for publication in ApJ
Current Density Functional approach to large quantum dots in intense magnetic fields
Creators: name: Pi, Marti
name: Barranco, Manuel
name: Emperador, Agusti
name: Lipparini, Enrico
name: Serra, Llorens
Publisher: name: arXiv
Year: 1997
Subjects: subject: Condensed Matter (cond-mat)
subject: FOS: Physical sciences

description: Within Current Density Functional Theory, we have studied a quantum dot made of 210 electrons confined in a disk geometry. The ground state of this large dot exhibits some features as a function of the magnetic field (B) that can be attributed in a clear way to the formation of compressible and incompressible states of the system. The orbital and spin angular momenta, the total energy, ionization and electron chemical potentials of the ground state, as well as the frequencies of far-infrared edge modes are calculated as a function of B, and compared with available experimental and theoretical results.
description: Typeset using Revtex, 17 pages and 13 Postscript figures
Rotating Black Hole Shadow in Perfect Fluid Dark Matter
Creators: name: Hou, Xian
name: Xu, Zhaoyi
name: Wang, Jiancheng
Publisher: name: arXiv
Year: 2018
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We study analytically the shadow cast by the rotating black hole in the perfect fluid dark matter. The apparent shape of the shadow depends upon the black hole spin $a$ and the perfect fluid dark matter intensity parameter $k$ ($k>0$). In general, the shadow is a perfect circle in the non-rotating case ($a=0$) and a deformed one in the rotating case ($a\neq 0$). The deformation gets more and more significant with the increasing $a$, similar to the Schwarzschild and Kerr black holes. In addition, there exists a reflection point $k_0$. When $kk_0$, the size of the shadow increases with the increasing $k$ and the distortion decreases with the increasing $k$. Furthermore, the energy emission rate of the black hole in the perfect fluid dark matter increases with the increasing $k$ and the peak of the emission shifts to higher frequencies. Finally, we propose that to observe the effect of the black hole spin $a$ and the perfect fluid dark matter intensity $k$ on the shadow of the black hole Sgr A$^{*}$ at the center of the Milky Way, highly improved techniques would be necessary for the development of future astronomical instruments.
description: 9 pages, 3 figures. arXiv admin note: text overlap with arXiv:1806.09415, arXiv:1804.08110
Hamiltonian structure and quantization of 2+1 dimensional gravity coupled to particles
Creators: name: Cantini, Luigi
name: Menotti, Pietro
name: Seminara, Domenico
Publisher: name: arXiv
Year: 2000
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: It is shown that the reduced particle dynamics of 2+1 dimensional gravity in the maximally slicing gauge has hamiltonian form. This is proved directly for the two body problem and for the three body problem by using the Garnier equations for isomonodromic transformations. For a number of particles greater than three the existence of the hamiltonian is shown to be a consequence of a conjecture by Polyakov which connects the auxiliary parameters of the fuchsian differential equation which solves the SU(1,1) Riemann-Hilbert problem, to the Liouville action of the conformal factor which describes the space-metric. We give the exact diffeomorphism which transforms the expression of the spinning cone geometry in the Deser, Jackiw, 't Hooft gauge to the maximally slicing gauge. It is explicitly shown that the boundary term in the action, written in hamiltonian form gives the hamiltonian for the reduced particle dynamics. The quantum mechanical translation of the two particle hamiltonian gives rise to the logarithm of the Laplace-Beltrami operator on a cone whose angular deficit is given by the total energy of the system irrespective of the masses of the particles thus proving at the quantum level a conjecture by 't Hooft on the two particle dynamics. The quantum mechanical Green's function for the two body problem is given.
description: 34 pages LaTex
The GW space-time method for the self-energy of large systems
Creators: name: Rieger, M. M.
name: Steinbeck, L.
name: White, I. D.
name: Rojas, H. N.
name: Godby, R. W.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Condensed Matter (cond-mat)
subject: FOS: Physical sciences

description: We present a detailed account of the GW space-time method. The method increases the size of systems whose electronic structure can be studied with a computational implementation of Hedin's GW approximation. At the heart of the method is a representation of the Green's function G and the screened Coulomb interaction W in the real-space and imaginary-time domain, which allows a more efficient computation of the self-energy approximation Sigma = iGW. For intermediate steps we freely change between representations in real and reciprocal space on the one hand, and imaginary time and imaginary energy on the other, using fast Fourier transforms. The power of the method is demonstrated using the example of Si with artificially increased unit cell sizes.
description: 6 figures
Experimental demonstration of linear and spinning Janus dipoles for polarisation and wavelength selective near-field coupling
Creators: name: Picardi, Michela F.
name: Neugebauer, Martin
name: Eismann, Joerg S.
name: Leuchs, Gerd
name: Banzer, Peter
name: Rodríguez-Fortuño, Francisco J.
name: Zayats, Anatoly V.
Publisher: name: arXiv
Year: 2019
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The electromagnetic field scattered by nano-objects contains a broad range of wave vectors and can be efficiently coupled to waveguided modes. The dominant contribution to scattering from subwavelength dielectric and plasmonic nanoparticles is determined by electric and magnetic dipolar responses. Here, we experimentally demonstrate spectral and phase selective excitation of Janus dipoles, sources with electric and magnetic dipoles oscillating out of phase, in order to control near-field interference and directional coupling to waveguides. We show that by controlling the polarisation state of the dipolar excitations and the excitation wavelength to adjust their relative contributions, directionality and coupling strength can be fully tuned. Furthermore, we introduce a novel spinning Janus dipole featuring cylindrical symmetry in the near and far field, which results in either omnidirectional coupling or noncoupling. Controlling the propagation of guided light waves via fast and robust near-field interference between polarisation components of a source is required in many applications in nanophotonics and quantum optics.
Insight4news Irish news related hashtagged tweet collection 15.07.2015-24.05.2017
Creators: name: Poghosyan, Gevorg
Publisher: name: figshare
Year: 2019
Subjects: subject: 80709 Social and Community Informatics
subject: FOS: Media and communications

description: The 1.3GB tar.gz file contains a 3.6GB (uncompressed) .txt file with 198'725'860 rows, each row of which is a tweet ID. These tweets have been collected in 15.07.2015-24.05.2017 period with the Hashtagger platform, which considered these tweets relevant to the monitored stream of news from Irish sources (The Irish Times, Irish Examiner, etc.).
All 198'725'860 tweets contain at least one hashtag.

Hydrate the tweet ids with Twarc (https://github.com/edsu/twarc#twitter-api-keys) and write to a file. You will need to provide Twarc with a set of Twitter API keys. twarc.py --hydrate tweet_ids.txt > tweets.json
It is probably not a good idea to hydrate all the tweets in one go, and may be better to split the file into chuncks and hydrate the tweets chunk-by-chunk. 
Electric field dependent structural and vibrational properties of the Si(100)-H(2 \times 1) surface and its implications for STM induced hydrogen desorption
Creators: name: Stokbro, K.
Publisher: name: arXiv
Year: 1999
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We report a first principles study of the structure and the vibrational properties of the Si(100)-H(2 \times 1) surface in an electric field. The calculated vibrational parameters are used to model the vibrational modes in the presence of the electric field corresponding to a realistic STM tip-surface geometry. We find that local one-phonon excitations have short lifetimes (10 ps at room temperature) due to incoherent lateral diffusion, while diffusion of local multi-phonon excitations are suppressed due to anharmonic frequency shifts and have much longer lifetimes (10 ns at room temperature). We calculate the implications for current induced desorption of H using a recently developed first principles model of electron inelastic scattering. The calculations show that inelastic scattering events with energy transfer $n \hbar ω$, where n>1, play an important role in the desorption process.
description: 10 pages, RevTeX, epsf files. submitted to surface science
A Non-Parametric Approach to Infer the Energy Spectrum and the Mass Composition of Cosmic Rays
Creators: name: Antoni, T.
Publisher: name: arXiv
Year: 2001
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The experiment KASCADE observes simultaneously the electron-photon, muon, and hadron components of high-energy extensive air showers (EAS). The analysis of EAS observables for an estimate of energy and mass of the primary particle invokes extensive Monte Carlo simulations of the EAS development for preparing reference patterns. The present studies utilize the air shower simulation code CORSIKA with the hadronic interaction models VENUS, QGSJet and Sibyll, including simulations of the detector response and efficiency. By applying non-parametric techniques the measured data have been analyzed in an event-by-event mode and the mass and energy of the EAS inducing particles are reconstructed. Special emphasis is given to methodical limitations and the dependence of the results on the hadronic interaction model used. The results obtained from KASCADE data reproduce the knee in the primary spectrum, but reveal a strong model dependence. Owing to the systematic uncertainties introduced by the hadronic interaction models no strong change of chemical composition can be claimed in the energy range around the knee.
description: 28 pages, 13 figures, Accepted for publication in Astroparticle Physics
A Novel Architecture for Smart Learning based on Soft Computing
Creators: name: Faizal Z Khan, Sultan Refa Alotaibi
Publisher: name: TuEngr Group
Year: 2021
Subjects: S-learning
PRISMA
Smart learning technique
Soft computing
Artificial Intelligence
Learning methodologies
Intelligent based systems
Student learning system (SLS)
AI-based smart learning framework.

description: International Transaction Journal of Engineering, Management, & Applied Sciences & Technologies, 12, 6, 12A6U: 1-10
Some remarks on 1D Schrödinger operators with localized magnetic and electric potentials
Creators: name: Golovaty, Yuriy
Publisher: name: arXiv
Year: 2018
Subjects: subject: Spectral Theory (math.SP)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 34L40, 81Q15

description: One-dimensional Schrödinger operators with singular perturbed magnetic and electric potentials are considered. We study the strong resolvent convergence of two families of the operators with potentials shrinking to a point. Localized $δ$-like magnetic fields are combined with $δ\,'$-like perturbations of the electric potentials as well as localized rank-two perturbations. The limit results obtained heavily depend on zero-energy resonances of the electric potentials. In particular, the approximation for a wide class of point interactions in one dimension is obtained.
description: 13 pages. arXiv admin note: text overlap with arXiv:1206.1941
Dynamical properties of the Landau-Ginzburg model with long-range correlated quenched impurities
Creators: name: Korutcheva, Elka
name: de la Rubia, F. Javier
Publisher: name: arXiv
Year: 1998
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We investigate the critical dynamics of the time-dependent Landau-Ginzburg model with non conserved n-component order parameter (Model A) in the presence of long-range correlated quenched impurities. We use a special kind of long-range correlations, previously introduced by Weinrib and Halperin. Using a double expansion in εand δwe calculate the critical exponent z up to second order on the small parameters. We show that the quenched impurities of this kind affect the critical dynamics already in first order of εand δ, leading to a relevant correction for the mean field value of the exponent z
description: 7 pages, REVTEX, to be published in Phys. Rev. B
Electrogenesis in a scalar field dominated epoch
Creators: name: Prokopec, Tomislav
Publisher: name: arXiv
Year: 2000
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this talk I discuss models in which a homogeneous scalar field is used to modify standard cosmology above the nucleosynthesis scale to provide an explanation for the observed matter-antimatter asymmetry of the Universe.
Photon transport in thin disordered slabs
Creators: name: Gopal, Venkatesh
name: Ramakrishna, S. Anantha
name: Sood, A. K.
name: Kumar, N.
Publisher: name: arXiv
Year: 1999
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We examine using Monte Carlo simulations, photon transport in optically `thin' slabs whose thickness L is only a few times the transport mean free path $l^{*}$, with particles of different scattering anisotropies. The confined geometry causes an auto-selection of only photons with looping paths to remain within the slab. The results of the Monte Carlo simulations are borne out by our analytical treatment which incorporates the directional persistence by the use of the Ornstein-Uhlenbeck process, which interpolates between the short time ballistic and long time diffusive regimes.
description: 4 figures as PS files
Spectral analysis of the extremely hot DA white dwarf PG0948+534
Creators: name: Werner, K.
name: Rauch, T.
name: Reindl, N.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: There is a striking paucity of hydrogen-rich (DA) white dwarfs (WDs) relative to their hydrogen-deficient (non-DA) counterparts at the very hot end of the WD cooling sequence. The three hottest known DAs (surface gravity log g $\geq$ 7.0) have effective temperatures around Teff = 140,000 K, followed by only five objects in the range 104,000 - 120,000 K. They are by far outnumbered by forty non-DAs with Teff = 100,000 - 250,000 K, giving a DA/non-DA ratio of 0.2. In contrast, this ratio is the inverse of that for the cooler WDs. One reason for this discrepancy could be uncertainties in the temperature determination of hot DAs using Balmer-line spectroscopy. Recent investigations involving metal-ionization balances in ultraviolet (UV) spectra indeed showed that the temperatures of some DAs were underestimated, but the paucity of extremely hot DAs prevailed. Here we present the results of a UV spectral analysis of one of the three hottest DAs, PG0948+534. We find that its temperature was strongly overestimated by recent Balmer line analyses. We correct it downward to 105,000 $\pm$ 5000 K, aggravating the hot-DA paucity. The Balmer-line problem encountered previously is not resolved by our non-LTE line-blanketed model atmospheres. We speculate that it might be related to the possible presence of a magnetosphere. This is supported by the V-band variability that shows a period of P=3.45 d (amplitude 0.19 mag), which we interpret as the star's rotation period. The metal abundances in PG0948+534 are affected by atomic diffusion and we conclude that the onset of diffusion in hot DAs occurs when they cool below Teff about 105,000 K. We discuss the possibility that the paucity of very hot DAs is a consequence of their fast evolutionary rate.
description: Accepted for publication in MNRAS
A Comprehensive Look at LH72 in the Context of Supergiant Shell LMC-4
Creators: name: Olsen, Knut A. G.
name: Kim, Sungeun
name: Buss, Jeremy F.
Publisher: name: arXiv
Year: 2001
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Stellar spectroscopy, UBV photometry, H$α$ imaging, and analysis of data from the ATCA \ion{H}{1} survey of the LMC are combined in a study of the LMC OB association LH 72 and its surroundings. LH 72 lies on the rim of a previously identified \ion{H}{1} shell, SGS-14, and in the interior of LMC-4, one of the LMC's largest known supergiant shells. Our analysis of the \ion{H}{1} data finds that SGS-14 is expanding with velocity $v_{exp}\sim15$ km s$^{-1}$, giving it an expansion age of $\sim$15 Myr. Through the stellar spectroscopy and photometry, we find similar ages for the oldest stars of LH 72, $\sim15-$30 Myr. We confirm that LH 72 contains an age spread of $\sim15-$30 Myr, similar to the range in ages of stars derived for the entire surrounding supergiant shell. Combining analysis of the O and B stars with H$α$ imaging of the \ion{H}{2} region DEM 228, we find that DEM 228 accounts for only 60% of the available ionizing Lyman continuum photons. Comparing the distribution of ionized gas with that of the \ion{H}{1}, we find that DEM 228 and LH 72 are offset by $\sim1-2\arcmin$ from the peak 21-cm emission, towards the interior of SGS-14. Taken together, these results imply that SGS-14 has cleared its interior of gas and triggered the formation of LH 72. On the basis of our results, we suggest that LMC-4 was not formed as unit but by overlapping shells such as SGS-14, and that LH 72 will evolve to produce a stellar arc similar to others seen within LMC-4.
description: 11 pages, 17 figures, uses aastex.cls, Accepted by the Astronomical Journal, to appear in June 2001 issue
Diffusive growth of a polymer layer by in sity polymerization
Creators: name: Wittmer, J. P.
name: Cates, M. E.
name: Johner, A.
name: Turner, M. S.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We consider the growth of a polymer layer on a flat surface in a good solvent by in-situ polymerization. This is viewed as a modified form of diffusion-limited aggregation without branching. We predict theoretically the formation of a pseudo-brush with density rhog(z) \propto z^{-2/3} and characteristic height \propto t^{3}. These results are found by combining a mean-field treatment of the diffusive growth (marginally valid in three dimensions) with a scaling theory (Flory exponent nu =3/5) of the growing polymers. We confirm their validity by Monte Carlo simulations.
description: 7 pages, 4 .eps figures, LATEX
Black holes with topologically nontrivial AdS asymptotics
Creators: name: Aros, R.
name: Troncoso, R.
name: Zanelli, J.
Publisher: name: arXiv
Year: 2000
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Asymptotically locally AdS black hole geometries of dimension d > 2 are studied for nontrivial topologies of the transverse section. These geometries are static solutions of a set of theories labeled by an integer 0 < k < [(d-1)/2] which possess a unique globally AdS vacuum. The transverse sections of these solutions are d-2 surfaces of constant curvature, allowing for different topological configurations. The thermodynamic analysis of these solutions reveals that the presence of a negative cosmological constant is essential to ensure the existence of stable equilibrium states. In addition, it is shown that these theories are holographically related to [(d-1)/2] different conformal field theories at the boundary.
description: 13 Pages, 3 figures, two columns, Revtex, last version for PRD
Low-Temperature Dephasing in Disordered Conductors: the Effect of ``1/f'' Fluctuations
Creators: name: Imry, Yoseph
name: Fukuyama, Hidetoshi
name: Schwab, Peter
Publisher: name: arXiv
Year: 1999
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Electronic quantum effects in disordered conductors are controlled by the dephasing rate of conduction electrons. This rate is expected to vanish with the temperature. We consider the very intriguing recently reported apparent saturation of this dephasing rate in several systems at very low temperatures. We show that the ``standard model'' of a conductor with static defects can {\em not} have such an effect. However, allowing some dynamics of the defects may produce it.
description: 6pages
Hamiltonian analysis of mimetic scalar gravity revisited
Creators: name: Ganz, Alexander
name: Karmakar, Purnendu
name: Matarrese, Sabino
name: Sorokin, Dmitri
Publisher: name: arXiv
Year: 2018
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We perform the Hamiltonian analysis of several mimetic gravity models and compare our results with those obtained previously by different authors. We verify that for healthy mimetic scalar-tensor theories the condition for the corresponding part of the Hamiltonian to be bounded from below is the positive value of the mimetic field energy density $λ$. We show that for mimetic dark matter possessing a shift symmetry the mimetic energy density remains positive in time, provided appropriate boundary conditions are imposed on its initial value, while in models without shift symmetry the positive energy density can be maintained by simply replacing $λ\to e^λ$. The same result also applies to mimetic $f(R)$ gravity, which is healthy if the usual stability conditions of the standard $f(R)$ gravity are assumed and $λ>0$. In contrast, if we add mimetic matter to an unhealthy seed action, the resulting mimetic gravity theory remains, in general, unstable. As an example, we consider a scalar-tensor theory with the higher-derivative term $(\Box φ)^2$, which contains an Ostrogradski ghost. We also revisit results regarding stability issues of linear perturbations around the FLRW background of the mimetic dark matter in the presence of ordinary scalar matter. We find that the presence of conventional matter does not revive dynamical ghost modes (at least in the UV limit). The modes, whose Hamiltonian is not positive definite, are non-propagating (have zero sound speed) and are associated with the mimetic matter itself. They are already present in the case in which the ordinary scalar fluid is absent, causing a growth of dust overdensity.
description: 40 pages, 0 figures
On Charged Mesoscopic Metallic Bubbles
Creators: name: Pomorski, Krzysztof
name: Dietrich, Klaus
Publisher: name: arXiv
Year: 1997
Subjects: subject: Condensed Matter (cond-mat)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We investigate the existence of stable charged metallic bubbles using the shell correction method. We find that for a given mesoscopic system of n atoms of a given metal and q less n (positive) elementary charges, a metallic bubble turns out to have a lower total energy than a compact spherical cluster, whenever the charge number q is larger than acritical charge number q_c. For a magic number (n-q) of free electrons, the spherical metallic bubble may become stable against fission.
description: 14 pages in Latex and 5 figures in the eps format
Fluctuation-Induced Interactions Between Ellipsoidal Particle and Planar Substrate Immersed in Critical Medium
Creators: name: Valchev, G. S.
name: Dantchev, D. M.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: In our study we investigate the behaviour of the net force (NF) emerging between an ellipsoidal particle and a thick plate (slab), when the interaction takes place in a near critical fluid medium with account for the omnipresent van der Waals forces (vdWF). Here we consider the case of complete wetting of the objects surfaces by the medium, due to strong adsorbing local surface potentials, exerted by thin solid coating films. The influence of the bulk inner regions of the particle and the slab on the constituents of the fluid results in long-ranged competing dispersion potentials. As a consequence from the critical fluctuations of the medium, the system experiences an additional effective interaction, traditionally termed critical Casimir force (CCF). The forces of interest are evaluated numerically from integral expressions obtained utilizing general scaling arguments and mean-field type calculations in combination with the so-called "surface integration approach" (SIA). Within the scenario considered here, this technique is applicable if one has knowledge of the forces between two parallel semi-infinite plates, confining in between some fluctuating fluid medium characterized by its temperature $T$ and chemical potential $μ$. It is demonstrated that for a suitable set of particle-fluid, slab-fluid, and fluid-fluid coupling parameters the competition between the effects due to the coatings and the core regions of the objects result, when one changes $T$ or $μ$, in {\it sign change} of the NF acting between the ellipsoid and the slab.
description: 8 pages, 2 figues. arXiv admin note: text overlap with arXiv:1702.04914