cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Graphene/liquid crystal based terahertz phase shifters
Creators: name: Wu, Yang
name: Ruan, Xuezhong
name: Chen, Chih-Hsin
name: Shin, Young Jun
name: Lee, Youngbin
name: Niu, Jing
name: Liu, Jingbo
name: Chen, Yuanfu
name: Yang, Kun-Lin
name: Zhang, Xinhai
name: Ahn, Jong-Hyun
name: Yang, Hyunsoo
Publisher: name: arXiv
Year: 2013
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Due to its high electrical conductivity and excellent transmittance at terahertz frequencies, graphene is a promising candidate as transparent electrodes for terahertz devices. We demonstrate a liquid crystal based terahertz phase shifter with the graphene films as transparent electrodes. The maximum phase shift is 10.8 degree and the saturation voltage is 5 V with a 50 um liquid crystal cell. The transmittance at terahertz frequencies and electrical conductivity depending on the number of graphene layer are also investigated. The proposed phase shifter provides a continuous tunability, fully electrical controllability, and low DC voltage operation.
ECONOMIC AND SOCIAL CONDITIONS OF BLACK SOUTH AFRICANS: THE EFFECTS OF XENOPHOBIC VIOLENCE AND DEVELOPMENTAL FAILURES
Creators: name: Akinola, Joseph Olawale
name: Ebele, Chinedu Okoro
Publisher: name: AYDEN JOURNAL
Year: 2024
Subjects: Poverty, Unemployment, Black South Africans, Post-Apartheid, Xenophobic Violence, Crisis, Development.

description: The study examined how poverty and unemployment conditions of black South Africans played a part in post-apartheid xenophobic violence and crisis of development in South Africa. A qualitative research approach and explanatory research design was adopted for the study. One research question and one research hypothesis guided the study. Data was also collected through interviews, textbooks, archival materials, journals, internet, government gazettes, periodicals, newspapers, conferences and seminar papers, magazines, etcetera for the analysis of the variables under investigation. The research interview questions were content validated by an expert in the field of social research while discriminatory method was used to ascertain the reliability of the data collection instruments. Qualitative tool such as the narrative analytic technique was adopted for the data analysis. The study reports that poverty and unemployment conditions of black South Africans played a part in post-apartheid xenophobic violence and crisis of development in South Africa. The study concluded that the poverty and unemployment condition of black South African Youths is a contributory factor to xenophobic violence in South Africa. The study advocates that there is an urgent need to create policies and programmes that will address the issue of high rate of poverty and unemployment among the South African youths.
Global Far-Ultraviolet Properties of the Cygnus Loop
Creators: name: Kim, Il-Joong
name: Seon, Kwang-Il
name: Lim, Yeo-Myeong
name: Lee, Dae-Hee
name: Han, Wonyong
name: Min, Kyoung-Wook
name: Edelstein, Jerry
Publisher: name: arXiv
Year: 2014
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present the C III λ977, O VI λλ1032, 1038 and N IV] λ1486 emission line maps of the Cygnus Loop, obtained with the newly processed data of Spectroscopy of Plasma Evolution from Astrophysical Radiation (SPEAR; also known as FIMS) mission. In addition, the Si IV+O IV] line complexes around 1400 Å are resolved into two separate emission lines, whose intensity demonstrates a relatively high Si IV region predicted in the previous study. The morphological similarity between the O VI and X-ray images, as well as a comparison of the O VI intensity with the value expected from the X-ray results, indicates that large portions of the observed O VI emissions could be produced from X-ray emitting gas. Comparisons of the far-ultraviolet (FUV) images with the optical and H I 21 cm images, reveal spatial variations of shock-velocity populations and high FUV extinction in the direction of a previously identified H I cloud. By calculating the FUV line ratios for several subregions of the Cygnus Loop, we investigate the spatial variation of the population of radiative shock velocities; and the effects of resonance scattering, X-ray emitting gas, and non-radiative shocks. The FUV and X-ray luminosity comparisons between the Cygnus Loop and the Vela supernova remnant suggest that the fraction of shocks in the early evolutionary stages is much larger in the Cygnus Loop.
description: 8 pages, 4 figures, 1 table. accepted for publication in ApJ
Improvement of Camelina sativa yield using a plant growth-promoting rhizobacterium
Creators: name: Miyashita, Hiroki
name: Fujita, Kounosuke
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Biotechnology
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: Plant Biology

description: Camelina sativa is an oilseed crop that produces large quantities of oil and has several agronomic traits that are advantageous. Recently, C. sativa has gained attention as a feedstock for biofuel production because of these properties. Different studies have been performed in many countries to improve C. sativa yield. In this study, we focused on using soil-dwelling bacteria to improve the yield of C. sativa. C. sativa were inoculated with Bacillus species and studied. Plants inoculated with bacteria showed higher pod numbers when compared with the uninoculated control. In comparison with the control, bacterial inoculation increased the seed yield (633 g m−2) by about threefold. These results suggest that the yield of C. sativa can be improved by incorporating bacteria in its cultivation.
title: Xcastor : Secure and scalable group communication in ad hoc networks
Creators: name: Schmittner, Milan
name: Hollick, Matthias
Publisher: name: IEEE
Year: 2016

description: Mobile ad hoc networks (MANETs) are emerging as a practical technology for emergency response communication in the case a centralized infrastructure malfunctions or is not available. Using smartphones as communication devices, MANETs may be readily established among the civilian population of affected areas. Beneficiaries would be civilian first responders, which may form small collaborating groups. Communication in such groups must be reliable for disaster response to be effective. In this paper, we address the issue of reliable group communication on the network layer. We design and implement the first secure explicit multicast routing protocol called Xcastor, in which we extend the secure and scalable routing concept of the Castor unicast routing protocol towards supporting reliable communication for large numbers of small groups. By simulation, we show significant performance improvements over Castor.
Quantum Teleportation from a Propagating Photon to a Solid-State Spin Qubit
Creators: name: Gao, Wei-bo
name: Fallahi, P.
name: Togan, E.
name: Delteil, A.
name: Chin, Y. S.
name: Miguel-Sanchez, J.
name: Imamoglu, A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The realization of a quantum interface between a propagating photon used for transmission of quantum information, and a stationary qubit used for storage and manipulation, has long been an outstanding goal in quantum information science. A method for implementing such an interface between dissimilar qubits is quantum teleportation, which has attracted considerable interest not only as a versatile quantum-state-transfer method but also as a quantum computational primitive. Here, we experimentally demonstrate transfer of quantum information carried by a photonic qubit to a quantum dot spin qubit using quantum teleportation. In our experiment, a single photon in a superposition state of two colors -- a photonic qubit is generated using selective resonant excitation of a neutral quantum dot. We achieve an unprecedented degree of indistinguishability of single photons from different quantum dots by using local electric and magnetic field control. To teleport a photonic qubit, we generate an entangled spin-photon state in a second quantum dot located 5 meters away from the first and interfere the photons from the two dots in a Hong-Ou-Mandel set-up. A coincidence detection at the output of the interferometer heralds successful teleportation, which we verify by measuring the resulting spin state after its coherence time is prolonged by an optical spin-echo pulse sequence. The demonstration of successful inter-conversion of photonic and semiconductor spin qubits constitute a major step towards the realization of on-chip quantum networks based on semiconductor nano-structures.
description: 12 pages, 3 figures, Comments welcome
Additional file 1 of Two decades of FDG-PET/CT in seminoma: exploring its role in diagnosis, surveillance and follow-up
Creators: name: Conduit, Ciara
name: Koh, Thuan Tzen
name: Hofman, Michael S
name: Toner, Guy C
name: Goad, Jeremy
name: Lawrentschuk, Nathan
name: Tai, Keen-Hun
name: Lewin, Jeremy H
name: Tran, Ben
Publisher: name: figshare
Year: 2022
Subjects: subject: Space Science
subject: Medicine
subject: Cell Biology
subject: Molecular Biology
subject: Neuroscience
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Cancer
subject: 111714 Mental Health
subject: FOS: Health sciences

description: Supplementary table 1
Spore inoculation of Bacillus pumilus TUAT1 strain, a biofertilizer microorganism, enhances seedling growth by promoting root system development in rice
Creators: name: Ngo, Ngoc Phuong
name: Yamada, Tetsuya
name: Higuma, Shungo
name: Ueno, Naoya
name: Saito, Kaya
name: Kojima, Katsuhiro
name: Maeda, Masumi
name: Yamaya-Ito, Hiroko
name: Ohkama-Ohtsu, Naoko
name: Kanekatsu, Motoki
name: Yokoyama, Tadashi
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Space Science
subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Cell Biology
subject: Genetics
subject: Ecology
subject: Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Infectious Diseases
subject: FOS: Health sciences
subject: Plant Biology

description: This study was conducted to determine the effects of plant growth-promoting rhizobacteria (PGPRs) on growth, root system development, nutrient absorption, and expression of genes related to root development in rice seedlings. Bacillus pumilus TUAT1, a beneficial PGPR bacterium that is used as a component of commercially available biofertilizer, was inoculated onto rice seedlings once weekly for 3 weeks, and effects on growth parameters were determined. Our results showed that inoculation of B. pumilus TUAT1 spores at a density of 1 × 107 colony-forming units (CFU) per mL yielded a significant increase in all traits compared to the control (water inoculum). In contrast, inoculation with vegetative cells did not yield significant effects (compared to control) in several traits, including the numbers of crown roots and lateral roots. CFUs increased with time and maintained to a higher number in the root zone than at the stem base of rice seedlings. Real-time quantitative reverse transcriptase-polymerase chain reaction of several genes known to be involved in root development revealed that B. pumilus TUAT1 inoculation led to increased accumulation of CRL5 transcripts and decreased accumulation of WOX11 transcripts in the basal stem, where crown root initiation occurs. Thus, our results suggest that spore inoculation of B. pumilus TUAT1 promotes rice crown root formation through suppression of cytokinin signal transduction by transcriptional control of CRL5 and WOX11. Consequently, the use of this bacterial strain may provide a means of improving growth, especially in root systems.
Information content of the weak-charge form factor
Creators: name: Reinhard, P. -G.
name: Piekarewicz, J.
name: Nazarewicz, W.
name: Agrawal, B. K.
name: Paar, N.
name: Rocca-Maza, X.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Parity-violating electron scattering provides a model-independent determination of the nuclear weak-charge form factor that has widespread implications across such diverse areas as fundamental symmetries, nuclear structure, heavy-ion collisions, and neutron-star structure. We assess the impact of precise measurements of the weak-charge form factor of ${}^{48}$Ca and ${}^{208}$Pb on a variety of nuclear observables, such as the neutron skin and the electric-dipole polarizability. We use the nuclear Density Functional Theory with several accurately calibrated non-relativistic and relativistic energy density functionals. To assess the degree of correlation between nuclear observables and to explore systematic and statistical uncertainties on theoretical predictions, we employ the chi-square statistical covariance technique. We find a strong correlation between the weak-charge form factor and the neutron radius, that allows for an accurate determination of the neutron skin of neutron-rich nuclei. We determine the optimal range of the momentum transfer $q$ that maximizes the information content of the measured weak-charge form factor and quantify the uncertainties associated with the strange quark contribution. Moreover, we confirm the role of the electric-dipole polarizability as a strong isovector indicator. Accurate measurements of the weak-charge form factor of ${}^{48}$Ca and ${}^{208}$Pb will have a profound impact on many aspects of nuclear theory and hadronic measurements of neutron skins of exotic nuclei at radioactive-beam facilities.
description: 10 pages, 4 figures
Hypocupremia: A Possible Association with Late Cortical Cerebellar Atrophy
Creators: name: Mittal, Shivam Om
name: Machado, Duarte G.
Publisher: name: Columbia University
Year: 2014
Subjects: subject: Neurosciences
subject: FOS: Clinical medicine

description: Background: We report a patient, diagnosed with late cortical cerebellar atrophy, who had persistent low serum copper levels.

Case report: A 48-year-old male developed progressive difficulty with balance, frequent falls, and dysarthric speech, which worsened over a short time span. He had an extensive ataxia work-up, which was unremarkable except for persistent low serum copper levels despite adequate supplementation. Magnetic resonance imaging of the brain showed marked cerebellar atrophy. The patient experienced progressive worsening of symptoms, which did not improve with either oral or parenteral copper supplementation.

Discussion: To our knowledge, ours is the first case report of late cortical cerebellar atrophy in the setting of low serum copper levels. The current report should trigger further research in mechanisms leading to copper deficiency and its possible role in cerebellar disease.
Random walk centrality for temporal networks
Creators: name: Rocha, Luis Enrique Correa
name: Masuda, Naoki
Publisher: name: arXiv
Year: 2014
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Social and Information Networks (cs.SI)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Nodes can be ranked according to their relative importance within the network. Ranking algorithms based on random walks are particularly useful because they connect topological and diffusive properties of the network. Previous methods based on random walks, as for example the PageRank, have focused on static structures. However, several realistic networks are indeed dynamic, meaning that their structure changes in time. In this paper, we propose a centrality measure for temporal networks based on random walks which we call TempoRank. While in a static network, the stationary density of the random walk is proportional to the degree or the strength of a node, we find that in temporal networks, the stationary density is proportional to the in-strength of the so-called effective network. The stationary density also depends on the sojourn probability q which regulates the tendency of the walker to stay in the node. We apply our method to human interaction networks and show that although it is important for a node to be connected to another node with many random walkers at the right moment (one of the principles of the PageRank), this effect is negligible in practice when the time order of link activation is included.
description: main text + supplementary material
Evaluating The Effectiveness Of English Coursebook Speaking Activities For Developing Libyan Secondary School Learners’ Oral Fluency
Creators: name: Elshegmani, Fatma
Publisher: name: University of Leicester
Year: 2023
Subjects: Uncategorized

description: This thesis presents the outcomes of two qualitative case studies which investigate the value and effectiveness of a coursebook according to the perceptions of two Libyan English language teachers and their learners. Specifically, it focuses on the speaking activities, and the extent to which the study participants perceive these to be effective in the development of oral fluency. It illuminates key aspects of the coursebook activities which aim to develop learners’ oral fluency with a focus on how they are actually taught. A two-level approach (macro and micro) to data collection, including coursebook analysis using Littlejohn’s framework, individual interviews with the teachers, focus group interviews with learners and semi-structured classroom observation were used. In answering the research questions, the following themes are addressed: the coursebook’s design; classroom teaching to examine how the coursebook is used by both the teachers and their learners; and the teachers’ and learners’ perceptions of the coursebook’s speaking activities as they relate to the promotion of oral fluency. The findings of the analysis reveal that some coursebook activities can play a role in encouraging oral fluency. However, the classroom observation revealed that the teachers tend to focus more on developing learners’ general oral proficiency, rather than oral fluency. While the teacher interviews demonstrate a high level of confidence regarding the teaching of oral fluency, the analysis indicated that the teachers’ knowledge of oral fluency, and by extension, the kinds of classroom activities that can promote oral fluency, were limited. The research study contributes to the literature on developing oral fluency by examining under-researched aspects of coursebook design, which in turn offered a focus on the coursebook activities in use (through the observation of the teachers and learners) and their perspectives on it (through the interviews). There are only a few studies that evaluate coursebook materials by their end-users.
title: Optimales Energie-Management über verteilte, beschränkte Gradientenverfahren
Creators: name: Zimmermann, Jan
name: Tatarenko, Tatiana
name: Willert, Volker
name: Adamy, Jürgen
Publisher: name: De Gruyter
Year: 2019

description: Dieser Beitrag beschäftigt sich mit verteilten, beschränkten Gradientenverfahren zur Optimierung eines Energie-Management-Problems. Zwei verschiedene Lösungsstrategien werden betrachtet. Zum einen wird ein Entkopplungsansatz analysiert, bei dem über einen Lagrange-Multiplikatoransatz die Beschränkungen in die Zielfunktion aufgenommen werden. Durch ein Gegenbeispiel wird gezeigt, dass dieses Verfahren nicht in jedem Fall auf das globale Optimum des Energie-Management-Problems konvergieren kann. Die zweite Strategie berücksichtigt Nebenbedingungen über einen Straffunktionsansatz und löst das Problem durch die Push-Sum-Konsensus-Dynamik. In der anschließenden Analyse dieses Verfahrens durch Simulation wird auf die Problematik der optimalen Parameterwahl sowie auf das Konvergenzverhalten bei unterschiedlicher Knoten- und Kantenanzahl des Graphen eingegangen.
The Foundations of Mozart Scholarship
Creators: name: Irvine, Thomas
Publisher: name: Columbia University
Year: 2006
Subjects: Music

description: What are the foundations of Mozart scholarship? The "facts" -there are many of them, and we are always learning more-of a remarkable composer's short life? Or the meanings we read in that life, and the meanings we experience in the music Mozart left behind? The composer's present jubilee year offers a chance to reflect on these questions. My reflections begin with a polemical call for change in Mozart scholarship proposed more than forty years ago by a young music historian to the skeptical audience of around-table discussion at an international conference. The young scholar, Wolfgang Plath, had just assumed the editorship of the largest Mozart project of his day (and of ours), the Neue Mozart-Ausgabe. The tone of his argument interests me as well as its contents: it was a polemic, designed as much to discredit the position of his opponents as to strengthen his own position. Plath's "straw man" was the school of German historiography that dominated writing in history and the history of the arts for more than a century, a school that sought, above all else, to discern meaning in history's ebb and flow. His critique, as we shall see, was as controversial as it was effective; I will argue here that specialist Mozart scholarship today has been shaped in no small part by it. Indeed, the issues Plath raised in making his argument have implications that extend far beyond the narrow confines of Mozart studies.
Reduced Chern-Simons Quiver Theories and Cohomological 3-Algebra Models
Creators: name: DeBellis, Joshua
name: Szabo, Richard J.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We study the BPS spectrum and vacuum moduli spaces in dimensional reductions of Chern-Simons-matter theories with N>=2 supersymmetry to zero dimensions. Our main example is a matrix model version of the ABJM theory which we relate explicitly to certain reduced 3-algebra models. We find the explicit maps from Chern-Simons quiver matrix models to dual IKKT matrix models. We address the problem of topologically twisting the ABJM matrix model, and along the way construct a new twist of the IKKT model. We construct a cohomological matrix model whose partition function localizes onto a moduli space specified by 3-algebra relations which live in the double of the conifold quiver. It computes an equivariant index enumerating framed BPS states with specified R-charges which can be expressed as a combinatorial sum over certain filtered pyramid partitions.
description: 47 pages
Additional file 2 of Dietary-derived vitamin B12 protects Caenorhabditis elegans from thiol-reducing agents
Creators: name: Winter, Alan D.
name: Tjahjono, Elissa
name: Beltrán, Leonardo J.
name: Johnstone, Iain L.
name: Bulleid, Neil J.
name: Page, Antony P.
Publisher: name: figshare
Year: 2022
Subjects: subject: Genetics
subject: FOS: Biological sciences

description: Additional file 2: Additional Materials and Methods. gDNA isolation, Sanger sequencing confirmations of rips-1 alleles in DTT strains, total RNA extraction, 3′RACE for rips-1, and genotyping. Additional Results. 3′ untranslated region from rips-1 (R08E5.3). Table S1. DTT resistance alleles. Table S2. RNAi mini-screen for B12-related pathways. Table S3.C. elegans strains. Table S4. Oligonucleotide primers. Table S5. Plasmids. Additional References.
Another Case of "Shopping Bag" Tremor: A Difficult to Classify Action Tremor
Creators: name: Robakis, Daphne
name: Louis, Elan D.
Publisher: name: Columbia University
Year: 2014
Subjects: subject: Neurosciences
subject: FOS: Clinical medicine

description: Zesiewicz et al.1 reported an unusual case of unilateral wrist tremor that occurred while the patient carried a weighted object (e.g., a shopping bag) or made a fist, and suggested that this could be a form of isolated isometric tremor. Here we report another patient who presented with a phenomenologically similar tremor.
Impact of fresh and aged palm shell biochar on N2O emissions, soil properties, nutrient content and yield of Komatsuna (Brassica rapa var. perviridis) under sandy soil conditions
Creators: name: Basalirwa, Daniel
name: Sudo, Shigeto
name: Wacal, Cosmas
name: Oo, Aung Zaw
name: Sasagawa, Daisuke
name: Yamamoto, Sadahiro
name: Masunaga, Tsugiyuki
name: Nishihara, Eiji
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Medicine
subject: Biotechnology
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: FOS: Biological sciences
subject: Developmental Biology
subject: Plant Biology

description: Biochar can reduce N2O emissions and it can be added to the soil once, whereas fertilizers are often applied every cultivation season. The aging of biochar in soil affects its functioning but it is unclear whether palm shell biochar (PSB) could still mitigate N2O emissions even when additional basal N fertilizers are applied 1 year after the initial biochar application. We studied the impact of fresh and aged PSB (0%, 6%, 12%, and 18% w/w of dry soil) on N2O emissions, soil properties, nutrient content and yield of Komatsuna (Brassica rapa var. perviridis) under sandy soil conditions. The aged PSB non-significantly reduced N2O emissions but significantly offset soil acidification, and maintained a high soil nutrient status. Biochar application with fertilizer significantly increased plant tissue K and Ca content but decreased N, P and Mg content compared to the treatments without biochar. At higher application rates, biochar had negative effects on crop yield but as it aged, the negative effects were offset as a result of the similar variation in plant N uptake. Since seasonal N fertilizer application seems to be inevitable in Komatsuna cultivation, addition of biochar could be a possible way of counteracting the effects of excessive fertilizer use. Further research is needed to assess the feasible biochar application rates for Komatsuna fields in various soil types under field conditions.
Reasoning about Space: The Hole Story
Creators: name: Varzi, Achille C.
Publisher: name: Columbia University
Year: 1996
Subjects: subject: Metaphysics
subject: Logic
subject: Philosophy
subject: FOS: Philosophy, ethics and religion

description: Much of our naive reasoning about space involves reasoning about holes and holed objects. We put things in holes, through holes, around them; we jump out of a hole or fall into one; we compare holes, measure them, enlarge them, fill them up. What exactly holes are, or even whether such dubious entities do indeed exist, these are of course questions one eventually needs to address in order to make good sense of such forms of reasoning. Holes are enigmatic, and it may be utterly difficult to specify adequate identity and individuation criteria for them. The purpose of this paper is to elaborate on that formalism and to illustrate how it can be exploited to provide a framework for more general patterns of qualitative spatial reasoning. In particular, after a general outline, I shall focus on some issues pertaining to the modelling, the representation, and the taxonomy of spatial inclusion. This is a topic that has received much attention in recent work in spatial reasoning, also in connection to a variety of applications, from naive physics to natural language semantics. My hope is to show that explicit commitment to holes as bona fide individuals introduces a novel and revealing (albeit certainly far from complete) perspective also with respect to such issues.
Should Student Employment Be Subsidized? Conditional Counterfactuals and the Outcomes of Work-Study Participation: Appendices A and B
Creators: name: Scott-Clayton, Judith E.
name: Minaya Lazarte, Veronica Milagros
Publisher: name: Columbia University
Year: 2014
Subjects: Education, Higher
Education--Finance

description: Appendices A and B to "Should Student Employment Be Subsidized? Conditional Counterfactuals and the Outcomes of Work-Study Participation" (DOI: 10.7916/D8JH3JTP).
Site effects in an alpine valley with strong velocity gradient: interest and limitations of the 'classical' BEM
Creators: name: Delepine, Nicolas
name: Semblat, Jean-François
Publisher: name: arXiv
Year: 2013
Subjects: subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: Seismic waves may be strongly amplified in deep alluvial basins due to the velocity contrast (or velocity gradient) between the various layers as well as the basin edge effects. In this work, the seismic ground motion in a deep alpine valley (Grenoble basin, French Alps) is investigated through various 'classical' Boundary Element models. This deep valley has a peculiar geometry ("Y"-shaped) and involves a strong velocity gradient between surface geological structures. In the framework of a numerical benchmark [21-23], a representative cross section of the valley has been proposed to investigate 2D site effects through various numerical methods. The 'classical' Boundary Element Method is considered herein to model the strong velocity gradient with a 2D piecewise homogeneous medium. For a large incidence angle, the transfer functions estimated from plane SH waves are close to the one computed with shallow SH point sources. The fundamental frequency is estimated at 0.33 Hz (SH wave) and the agreement with previous experimental results (spectral ratios) is good. Comparisons between 1D and 2D amplification are then performed: the values of the fundamental frequency and the corresponding amplitude are larger in 2D. Converting frequency domain results into the time domain, we underline surface waves generated at the valley edges and the directivity effect for the amplified wave-field. In the time domain for plane SV-wave, we also computed the ground motion for a strong seismic event (M=6): time duration and peak ground velocity are found to be 3 times larger than for the input signal. Such 2D models involving basin effects are then capable to recover the high amplification level measured in the field. Nevertheless, to deal with complex 3D basins as also proposed in the "ESG" benchmark [21-23], the capabilities of the classical Boundary Element Method are limited. As shown recently [43,47,52], such improvements as the fast multipole formulation (FM-BEM) may be a promising alternative for future 3D simulations.
Should Student Employment Be Subsidized? Conditional Counterfactuals and the Outcomes of Work-Study Participation
Creators: name: Scott-Clayton, Judith E.
name: Minaya Lazarte, Veronica Milagros
Publisher: name: Columbia University
Year: 2014
Subjects: Education, Higher
Education--Finance

description: Student employment subsidies are one of the largest types of federal employment subsidies, and one of the oldest forms of student aid. Yet it is unclear whether they help or harm students’ long term outcomes. We present a framework that decomposes overall effects into a weighted average of effects for marginal and inframarginal workers. We then use an application of propensity scores, which we call conditional-counterfactual matching, in which we estimate the overall impact, and the impact under two distinct counterfactuals: working at an unsubsidized job, or not working at all. Finally, we estimate the effects of the largest student employment subsidy program—Federal Work-Study (FWS)—for a broad range of participants and outcomes.
Our results suggest that about half of FWS participants are inframarginal workers, for whom FWS reduces hours worked and improves academic outcomes, but has little impact on future employment. For students who would not have worked otherwise, the pattern of effects reverses. With the exception of first-year GPA, we find scant evidence of negative effects of FWS for any outcome or subgroup. However, positive effects are largest for lower-income and lower-SAT subgroups, suggesting there may be gains to improved targeting of funds.
2D fuzzy Anti-de Sitter space from matrix models
Creators: name: Jurman, Danijel
name: Steinacker, Harold
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We study the fuzzy hyperboloids AdS^2 and dS^2 as brane solutions in matrix models. The unitary representations of SO(2,1) required for quantum field theory are identified, and explicit formulae for their realization in terms of fuzzy wavefunctions are given. In a second part, we study the (A)dS^2 brane geometry and its dynamics, as governed by a suitable matrix model. In particular, we show that trace of the energy-momentum tensor of matter induces transversal perturbations of the brane and of the Ricci scalar. This leads to a linearized form of Henneaux-Teitelboim-type gravity, illustrating the mechanism of emergent gravity in matrix models.
description: 25 pages
title: The PRORETA 4 City Assistant System
Creators: name: Schwehr, Julian
name: Luthardt, Stefan
name: Dang, Hien
name: Henzel, Maren
name: Winner, Hermann
name: Adamy, Jürgen
name: Fürnkranz, Johannes
name: Willert, Volker
name: Lattke, Benedikt
name: Höpfl, Maximilian
name: Wannemacher, Christoph
Publisher: name: De Gruyter
Year: 2019

description: The use of machine learning in driver assistance systems allows to significantly enhance their functionalities. In particular, it allows to personalize systems by evaluating the driver’s past behavior. Such personalization is especially relevant for recommendations in maneuvers where the specific maneuver embodiment strongly depends on the driver’s momentary driving style and attention. Led by this idea, PRORETA 4 developed a prototypical City Assistant System, which gives the driver a personalized recommendation in urban scenarios. To adapt the recommendations and warnings appropriately, the system incorporates the learned momentary driving style and the driver’s gaze behavior. In this work, we describe the main functional blocks of the system, present our solutions to major implementation challenges and also discuss the safety of the used learning algorithm.
Evaluation of fly ash, apatite and rice straw derived-biochar in varying combinations for in situ remediation of soils contaminated with multiple heavy metals
Creators: name: Dang, Van Minh
name: Van, Huu Tap
name: Duong, Hoa Thi Minh
name: Nguyen, Duy Hai
name: Chao, Huan-Ping
name: Nguyen, Lan Huong
name: Lin, Chu-Ching
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Space Science
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: FOS: Biological sciences

description: In-situ sorbent amendment is a relatively low-cost, low-impact approach for remediation of soil contaminated with heavy metals (HMs), and thus is considered a way to be favored in developing countries. In this study, materials of non-hazardous, alkaline agronomic and industrial by-products were used as sorbents to explore their capacity of in situ immobilization of multiple HMs in mining-impacted arable soil. These sorbents included fly ash (FA), biochar (BC) and apatite (AP) and they were implemented with varying ratios of combinations. Results of soil microcosm tests showed that after incubation for 90 days, concentrations of Pb, Zn, and Cd in their exchangeable forms determined by a sequential extraction method significantly decreased in amended soils, as opposed to the unamended control. Of the five sets of amendments, the composite of FA, BC, and AP resulted in the maximum reduction (up to 80%) in the mobility of Pb, Zn, and Cd in soils. The mechanisms underlying the immobilization of HMs in amended soils might involve processes of surface precipitation, ion exchange and complexation, in which the physicochemical properties of sorbent materials played an important role. The immobilization efficacy of sorbent amendments on HMs in soil was further supported by pot experiments in which significant inhibition of HM accumulation in the belowground and aboveground tissues of maize was observed after 50-day cultivation in amended soils as compared with control soil. Together, these results suggest that the application of cost-saving and environmentally friendly materials derived from wastes as sorbents to remediate soils contaminated with multiple HMs is promising for developing countries like Vietnam.
Improving the Targeting of Treatment: Evidence from College Remediation
Creators: name: Scott-Clayton, Judith E.
name: Crosta, Peter Michael
name: Belfield, Clive
Publisher: name: Columbia University
Year: 2014
Subjects: Education, Higher
Educational tests and measurements

description: At an annual cost of roughly $7 billion nationally, remedial coursework is one of the single largest interventions intended to improve outcomes for underprepared college students. But like a costly medical treatment with non-trivial side effects, the value of remediation overall depends upon whether those most likely to benefit can be identified in advance. This NBER working paper uses administrative data and a rich predictive model to examine the accuracy of remedial screening tests, either instead of or in addition to using high school transcript data to determine remedial assignment.
The authors find that roughly one in four test-takers in math and one in three test-takers in English are severely mis-assigned under current test-based policies, with mis-assignments to remediation much more common than mis-assignments to college-level coursework. Using high school transcript information—either instead of or in addition to test scores—could significantly reduce the prevalence of assignment errors. Further, the choice of screening device has significant implications for the racial and gender composition of both remedial and college-level courses. Finally, if institutions took account of students’ high school performance, they could remediate substantially fewer students without lowering success rates in college-level courses.
The effect of higher-order mesonic interactions on the chiral phase transition and the critical temperature
Creators: name: Abu-Shady, M.
name: Mansour, H.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In the present work, higher-order mesonic interactions are included in the linear sigma model at a finite temperature. The effective potential is minimized in the calculations of the sigma and pion effective masses. The field equations have been solved in the mean-field approximation, by using the extended iteration method at a finite temperature. The order of chiral phase transition, the effective sigma and pion masses, and the effective mesonic potential are investigated as functions of the temperature. We find that the chiral phase transition satisfies the Goldstone theorem below the critical temperature point, when the minimization condition is satisfied in the chiral limit. The value of the critical temperature is reduced as compared with that of the original model in agreement with lattice QCD results. The modified model is compared to with models in other works.
description: 8 pages, 9 figures. http://www.ujp.bitp.kiev.ua
Incorporation of winter grasses suppresses summer weed germination and affects inorganic nitrogen in flooded paddy soil
Creators: name: Utami, Asih Indah
name: Bimantara, Putu Oki
name: Umemoto, Riho
name: Sabri, Riza Kurnia
name: Kautsar, Valensi
name: Tawaraya, Keitaro
name: Hanudin, Eko
name: Cheng, Weiguo
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Biochemistry
subject: Cell Biology
subject: Molecular Biology
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: FOS: Biological sciences
subject: Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Plant Biology

description: Laboratory experiments were conducted to investigate how incorporation of the winter grasses foxtail (Alopecurus aequalis) and milk vetch (Astragalus sinicus) into flooded paddy soil affects the germination of summer weeds and soil inorganic nitrogen (N) levels. Polyethylene terephthalate (PET) vessels (10.0 × 8.0 × 15.0 cm) were filled with 0.7 kg air-dried soil that had been collected from organic paddy fields located in Tochigi, Japan. Foxtail and milk vetch were then independently incorporated into the soil at rates of 0% (untreated control), 0.25%, 0.5%, 1%, and 1.5%, with four repetitions per treatment. The PET vessels were placed in a growth chamber (Biotron) set to day/night temperatures and humidities of 27/18°C and 70%/65%, respectively, and with an illuminance of 40,000 lx (12 h) for 28 days, and the total number of weeds and changes in the electrical conductivity (EC) of the surface water were investigated throughout this period, while changes in soil inorganic N were determined at the ends of the experiments. The incorporation of both foxtail and milk vetch significantly suppressed the germination of summer weeds by 56% and 50%, respectively, at incorporation rates of 1% and by 78% and 77%, respectively, at incorporation rates of 1.5% compared with their respective controls. There was a high and significant positive correlation between both the rate of winter grass incorporation and the degree of growth suppression and EC. Incorporation of foxtail at rates of 0.25% and 0.5% significantly increased the inorganic N contents of the sub-layer by an average of 68% compared with the control but had no significant effect in the top layer, whereas the incorporation of milk vetch at a rate of 1% significantly increased the inorganic N contents of both the top layer and sub-layer by 200% and 316%, respectively, compared with the control. Furthermore, the effect of milk vetch on inorganic N significantly increased with an increase in the rate of incorporation. These findings demonstrate that incorporation of the winter grasses foxtail and milk vetch into flooded organic paddy soil can suppress weed growth and act as a source of inorganic N.
title: Visual Inspection of Curved Particle Accelerator Beam Pipes with a Modular Robot
Creators: name: Schweizer, Nicolai
name: Pongrac, Ivan
Publisher: name: JACoW Publishing
Year: 2019

description: Inspecting ultra-high vacuum pipe systems of particle accelerators without disassembling the beam pipes is a complex challenge. In particular, curved sections of particle accelerators require a unique approach for the examination of the interior. For the planned heavy ion synchrotron SIS100 at FAIR, an inspection robot is currently under development, featuring an optical imaging system with which the robot can be navigated through the beam pipe. We present the current prototype, which is based on a modular snake-like robot with active wheels and joints. Due to the stipulated low movement velocity, it can be shown that a kinematic model is sufficient to control the robot whereas dynamical effects can be neglected. This concept is proven in experiments with the prototype. At the current development status, the robot is controlled manually by setting the velocity of the first module and its desired turning angle. In simulations we include a CAD model of a dipole chamber of the SIS100 and let an operator successfully navigate the robot through the beam pipe while only observing the camera image.
Inconsistency Without Contradiction
Creators: name: Varzi, Achille C.
Publisher: name: Columbia University
Year: 1997
Subjects: subject: Philosophy
subject: FOS: Philosophy, ethics and religion
subject: Logic

description: My purpose in this paper is not to defend or attack the ersatz conception— the view that unactualized worlds are merely linguistic descriptions of the ways this world of ours might have been. Rather, I am interested in that conception insofar as it pertains to the challenge raised by Lewis. Suppose we do not treat ‘in so-and-so world’ as a restricting modifier. Suppose we take Conan Doyle to be describing a bona fide world, though a world that is impossible because of some unfortunate discrepancies. What are we to make of the truths and falsehoods in such a world? Can we distinguish its contradictory truths from contradictory falsehoods about it? I want to say that we can. If an impossible world is one in which there are discrepancies of the sort illustrated by the Watson example—a world in which certain facts both do and do not obtain— then we can keep such worlds under logical control exactly as we can keep the Holmes stories under control. There are discrepancies, but these discrepancies are local and do not force incoherence upon our discourse about them because they can be explained away by reference to an underlying set of coherent goings-on.
title: Paleoseismology of the northern Ōhāriu Fault, a study into earthquake recurrence and slip rate
Creators: name: Coffey, Genevieve L.
name: Langridge, Robert M.
name: Van Dissen, Russ J.
name: Clark, Kate J.
name: Litchfield, Nicola J.
name: Morgenstern, Regine
name: Palmer, A.
Publisher: name: GNS Science
Year: 2022

description: The Kāpiti Coast and Horowhenua districts are areas of rapid growth and development with expansion of housing and construction of major traffic infrastructure. Extending through these regions is the 60 km-long Northern Ōhāriu Fault, which is thought to be the northern extension of the Ōhāriu Fault. Little work on the Northern Ōhāriu Fault has been done since the early 2000s and given the potential for continuous ruptures along the Ōhāriu and Northern Ōhāriu faults, as well as increasing development in the Wellington-Levin corridor, further study is warranted. In this report we present the results of two paleoseismic trenches and a slip rate pit excavated across a branch of the Northern Ōhāriu Fault and an offset alluvial terrace, respectively. The work has been funded by the It’s Our Fault programme. Evidence of earthquakes spanning the Holocene and into the Late Pleistocene is identified from two paleoseismic trenches. Radiocarbon dating in one trench constrains the ages of the two most recent earthquakes to 120–273 cal yr BP and 1063–1271 cal yr BP and these are used to develop a preliminary recurrence interval of 400–2,300 years. Individual earthquakes in the other trench cannot be dated but suggest the recurrence interval is closer to the longer end of this range. At this stage, a slip rate cannot be derived from the pit excavated in an offset terrace due to uncertainty in when displacement began. The earthquake timings and recurrence interval of the Northern Ōhāriu Fault determined here are in good agreement with that of the Ōhāriu Fault. The results of this work suggest that either the Northern Ōhāriu and Ōhāriu faults form a single continuous structure along which earthquakes can rupture (with a preliminary maximum magnitude of Mw 7.9), or that earthquake activity on each fault is highly influenced by the other causing both faults to fail in earthquakes together or very close in time. Furthermore, earthquakes on the Northern Ōhāriu and Ōhāriu faults overlap in time with earthquakes on the Wellington and Rangatira faults, confirming earlier suggestions that earthquakes in the lower North Island may not be restricted to single faults and instead may occur as multi-fault ruptures. Results described in this report are preliminary and will be developed further with additional analysis and age modelling. However, these results demonstrate that the Northern Ōhāriu Fault is more active than previously thought and have implications for multi-fault rupture in the lower North Island, highlighting the importance of further research to understand the earthquake timing of this and other faults in the area. (The authors)