cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Could Chemical LLMs benefit from Message Passing
Creators: name: Xie, Jiaqing
name: Chi, Ziheng
Publisher: name: arXiv
Year: 2024
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Pretrained language models (LMs) showcase significant capabilities in processing molecular text, while concurrently, message passing neural networks (MPNNs) demonstrate resilience and versatility in the domain of molecular science. Despite these advancements, we find there are limited studies investigating the bidirectional interactions between molecular structures and their corresponding textual representations. Therefore, in this paper, we propose two strategies to evaluate whether an information integration can enhance the performance: contrast learning, which involves utilizing an MPNN to supervise the training of the LM, and fusion, which exploits information from both models. Our empirical analysis reveals that the integration approaches exhibit superior performance compared to baselines when applied to smaller molecular graphs, while these integration approaches do not yield performance enhancements on large scale graphs.
description: Accepted at ACL @ Languages and Molecules 2024. In Proceedings of ACL 2024
Electroweak structure of the nucleon, meson cloud and light-cone wavefunctions
Creators: name: Pasquini, B.
name: Boffi, S.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The meson-cloud model of the nucleon consisting of a system of three valence quarks surrounded by a meson cloud is applied to study the electroweak structure of the proton and neutron. Light-cone wavefunctions are derived for the dressed nucleon as pictured to be part of the time a bare nucleon and part of the time a baryon-meson system. Configurations are considered where the baryon can be a nucleon or a Δand the meson can be a pion as well as a vector meson such as the ρor the ω. An overall good description of the electroweak form factors is obtained. The contribution of the meson cloud is small and only significant at low Q^2. Mixed-symmetry S'-wave components in the wavefunction are most important to reproduce the neutron electric form factor. Charge and magnetization densities are deduced as a function of both the radial distance from the nucleon center and the transverse distance with respect to the direction of the three-momentum transfer. In the latter case a central negative charge is found for the neutron. The up and down quark distributions associated with the Fourier transform of the axial form factor have opposite sign, with the consequence that the probability to find an up (down) quark with positive helicity is maximal when it is (anti)aligned with the proton helicity.
description: references updated and typos in figure 2 corrected; to be published in Phys. Rev. D
Worldwide trends in methods for harvesting and extracting industrial roundwood
Creators: name: Lundbäck, Mikael
name: Häggström, Carola
name: Nordfjell, Tomas
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Ecology
subject: FOS: Biological sciences
subject: Sociology
subject: FOS: Sociology
subject: 69999 Biological Sciences not elsewhere classified
subject: Plant Biology

description: Globally, almost 2 billion cubic meters of industrial roundwood are harvested yearly. Two of the most common methods of harvest and extraction are cut-to-length (CTL) and full-tree or tree-length (FT/TL). The aim of this study was to compile data on annual volumes of industrial roundwood harvested by the main methods in forestry countries. To quantify the effect of potential explanatory variables, the data were subjected to linear regression analysis, using shares of roundwood volumes harvested by fully mechanized CTL and/or FT/TL as response variables. Generally, high diesel price and Gross Domestic Product appear to favor CTL, while high shares of steep terrain (>20°) in forest land decrease the leve l of both mechanization and CTL, and low Social Security Rate (SSR) favor FT/TL. Two models were created for CTL, one with an R2 of 0.64 and another more complex with an R2 of 0.75. A separate model for mechanization (CTL and FT/TL together) showed an R2 0.57. The CTL models could potentially be used to predict shares of roundwood volumes harvested by CTL in countries not included in this study. Predictions for countries with large harvested volumes, e.g. China and India, are presented here, but they require validation, as does the model’s applicability for countries with small harvested volumes. Countries with less than 10% of steep slope forests are almost exclusively mechanized according to the model. For FT/TL, the proposed model is probably not sufficiently robust for prediction, but it highlights SSR as one important explanatory variable.
Meromorphic solutions of higher order Briot-Bouquet differential equations
Creators: name: Eremenko, A.
name: Liao, L. W.
name: Ng, T. W.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 34M05, 30D05

description: For differential equations $P(y^{(k)},y)=0,$ where $P$ is a polynomial, we prove that all meromorphic solutions having at least one pole are elliptic functions, possibly degenerate.
The quest for national unity : Ottawa's constitutional strategy in the Trudeau era
Creators: name: Mikloska, John A.
Publisher: name: University of British Columbia
Year: 2010

description: The rise of Quebecois nationalism in the 1960s and regionalism in the 1970s presented a considerable threat to the Canadian state. A variety of political, institutional, economic and socio-cultural factors have contributed to these phenomena. One of the primary preoccupations of the federal government in recent decades has been the resolution of the national unity problem. During the tenure of Pierre Trudeau as prime minister, Ottawa developed an intriguing and multi-faceted constitutional strategy to deal with the challenges facing Canadian federalism. This thesis has divided that strategy into three major parts: the reform of federal institutions in an intrastate direction; the policies of bilingualism and multiculturalism; and the entrenchment of a constitutional Bill of Rights. These initiatives may be breifly described as a restructuring of institutions and state—society relations designed to strengthen the national government and community at the expense of their provincial counterparts. The federal plan was an attempt to build a pan-Canadian identity which transcended regional identities, to limit the legislative capacities of provincial governments, and to increase the salience of non-territorial cleavages. The national unity strategy of the Trudeau government can be viewed as part of a historical pattern of federal initiatives designed to prevent the provincialization of the country. However, by emphasizing Canada's linguistic duality and cultural diversity and by shifting the focus onto individual rights and the symbolic aspects of social organization, Trudeau's formula diverged somewhat from previous nation-building ventures.
Teacher cognition: examining teachers’ mental lives in language education
Creators: name: Bruzzano, Chiara
Publisher: name: Ricerche di Pedagogia e Didattica. Journal of Theories and Research in Education
Year: 2018
Subjects: teacher cognition; teacher beliefs; teacher knowledge; language education; sociocultural theory

description: This paper reviews the literature pertaining to the field of teacher cognition, which investigates the mental constructs and the practices of teachers, with a particular focus on teachers of foreign and second languages. Given the wide uptake of teacher cognition as a framework for researching teachers, this review is meant to provide a starting point for researchers to take account of the evolution of the field and its future directions. As is evident from this review, what was initially substantially a cognitively-oriented endeavour, aiming to understand what teachers held in their minds, has now morphed into research that is essentially sociocultural in nature, viewing teachers’ cognitions and practices as complex and embedded in context. This paper thus analyses research investigating the fundamental constructs of beliefs and knowledge and discusses certain limitations of such research, while examining the field’s main emerging and promising themes of teacher identity and emotions.
description: Ricerche di Pedagogia e Didattica. Journal of Theories and Research in Education, V. 13, N. 3 (2018)
Martian seismic anisotropy underneath Elysium Planitia revealed by direct S wave splitting
Creators: name: Shi, Jing
name: Han, Cunrui
name: Wang, Tao
name: Qi, Chao
name: Chen, Han
name: Yu, Zhihan
name: Geng, Jiaqi
name: Yang, Minghan
name: Wang, Xu
name: Chen, Ling
name: Hui, Hejiu
Publisher: name: arXiv
Year: 2024
Subjects: subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: Seismic anisotropy, arising from the crystallographic or lattice-preferred orientation of anisotropic minerals or the shape-preferred orientation of melts or cracks, can establish a critical link between Mars's past evolution and its current state. So far, although seismic anisotropy in Mars has been proposed due to different velocities of vertically and horizontally polarized shear waves in the Martian crust, obtained from crustal converted waves, multiples, and surface waves recorded by the InSight seismometer, the evidence is plausible. Notably, the shear wave splitting, which stands out as a straight indicator of seismic anisotropy, has not been reported using marsquake records. In this study, we employ Low-frequency marsquakes detected by the InSight seismometer to reveal shear wave splitting in Mars. We find that the direct S waves of three marsquake recordings (S0173a, S0235b, and S1133c) with high signal-to-noise ratios exhibit the splitting pheonmenon. We rule out the possibility of apparent anisotropy through synthetic tests, affirming the presence of seismic anisotropy in Mars. The delay time (about 1.33 s on average) measured from the direct S wave splitting is too large to be solely attributed to the seismic anisotropy in the upper crust (0 - 10 km) beneath the InSight. Thus, seismic anisotropy in the deeper region of Mars is indispensable. Combined with other geophysical evidence near the InSight landing site, the strong seismic anisotropy observed in this study implies the porous crust with aligned cracks being greater than 10 km beneath the InSight and/or the presence of an active mantle plume underneath the Elysium Planitia of Mars.
description: Manuscript has been submitted to Earth and Planetary Science Letters; 9 figures; 33 pages
Effective Learning Experiences with UDL in teacher training at Universities
Creators: name: Emili, Enrico Angelo
name: Schumacher, Susanne
name: Stadler-Altmann, Ulrike
Publisher: name: Ricerche di Pedagogia e Didattica. Journal of Theories and Research in Education
Year: 2019
Subjects: multi-modal communication; Person-Environment-Theory; professionalization; quality assurance in teacher training

description: Three categories of competencies are required living a successful life in a complex-functional society. The government pursues the implementation of these competence categories, defined by the OECD project group ‘Definition and Selection of Competencies’ (DeSeCo; OECD 2014), in the context of education policy management measures e.g. in framework guidelines or study programs for educational institutions, starting with kindergarten, through primary and secondary schools to universities. Introductorily the following article shows the understanding of the three competence categories to the educational sciences (1). Secondly, we outline the educational policy context given in Italy and Alto Adige using the prominent topic of inclusion as an example (2). Based on these, some more concrete initial points for professionalization of pedagogical specialists can be outlined (3). In a fourth step the development of the teaching program for the Master of Education in Primary Education at the Free University of Bolzano is given as an example how these elements could be incorporated in an academic teacher training (4). According to the discussion of results of actual teacher education research and university didactics hypotheses on the connections between supply quality and the subjective fit of the students' academic requirements and competences are expressed.
description: Ricerche di Pedagogia e Didattica. Journal of Theories and Research in Education, V. 14, N. 1 (2019)
Radiatively-driven black-hole winds revisited
Creators: name: Yamamoto, Ryoya
name: Fukue, Jun
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We examine general relativistic radiatively-driven spherical winds, using the basic equations for relativistic radiation hydrodynamics under the moment formalism. Moment equations are often closed, using the equilibrium diffusion approximation, which has an acausal problem, and furthermore, gives nodal-type critical points. Instead, we use the nonequilibrium diffusion approximation with a closure relation of a variable Eddington factor, $f(τ,β)$, where $τ$ is the optical depth and $β$ is the flow speed normalized by the speed of light. We then analyze the critical properties in detail for several parameters, and found that there appear saddle-type critical points as well as nodal type and spiral one. The most suitable type is the saddle one, which appears in a region close to a black hole. We also calculate transonic solutions with typical parameters, and show that the luminosity is almost comparable to the Eddington luminosity, the gas is quickly accelerated in the vicinity of the black hole, and wind terminal speeds are on the order of 0.1$-$0.3$~c$. These results of radiatively-driven black hole winds can be applied, e.g., to ultra-fast outflows (UFOs), which are supposed to be fast outflows from the vicinity of super massive black holes.
description: 12 pages, 15 figures, published in MNRAS, some typos in equation (10) of the published article have been corrected
From Media Education to Digital Citizenship. Origins, perspectives and policy implementations in the school systems across Europe
Creators: name: Soriani, Alessandro
Publisher: name: Ricerche di Pedagogia e Didattica. Journal of Theories and Research in Education
Year: 2018
Subjects: Digital citizenship; digital literacy; media and information literacy; national school policies; European guidelines

description: The aim of this article is to describe the concept of digital citizenship, as it emerges from disciplines such as Media Education, Digital and Media Literacy and Media and Information Literacy, and how this is translated into national school innovation plans in some European countries.

The first part of the article analyses the concept of media education, by carrying out an operation of disambiguation between the different disciplines often confused among them: Media Education, Digital and Media Literacy and Media and Information Literacy.

The first part of the paper aims to disambiguate the various terms related to media literacy in general, often used interchangeably across the various disciplines, namely Media Education, Digital and Media Literacy and Media and Information Literacy.

The second part of the paper illustrates and compares several international projects that support the formalization of competence frameworks for digital citizenship while highlighting the need to move towards a concept of technology education that also supports aspects related to active citizenship, democratic participation in society and take into account the social-relational dimension.
In conclusion, national digital innovation plans for schools in Spain, Germany, UK, France and Italy will be presented with the aim of highlighting the aspects of innovation while critically reflecting on the concept of digital citizenship education therein.
description: Ricerche di Pedagogia e Didattica. Journal of Theories and Research in Education, V. 13, N. 3 (2018)
Thermodynamics of low dimensional spin-1/2 Heisenberg ferromagnets in an external magnetic field within Green function formalism
Creators: name: Antsygina, T. N.
name: Poltavskaya, M. I.
name: Poltavsky, I. I.
name: Chishko, K. A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: The thermodynamics of low dimensional spin-1/2 Heisenberg ferromagnets (HFM) in an external magnetic field is investigated within a second-order two-time Green function formalism in the wide temperature and field range. A crucial point of the proposed scheme is a proper account of the analytical properties for the approximate transverse commutator Green function obtained as a result of the decoupling procedure. A good quantitative description of the correlation functions, magnetization, susceptibility, and heat capacity of the HFM on a chain, square and triangular lattices is found for both infinite and finite-sized systems. The dependences of the thermodynamic functions of 2D HFM on the cluster size are studied. The obtained results agree well with the corresponding data found by Bethe ansatz, exact diagonalization, high temperature series expansions, and quantum Monte Carlo simulations.
description: 11 pages, 14 figures
Random Access Broadcast: Stability and Throughput Analysis
Creators: name: Shrader, Brooke
name: Ephremides, Anthony
Publisher: name: arXiv
Year: 2007
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: A wireless network in which packets are broadcast to a group of receivers through use of a random access protocol is considered in this work. The relation to previous work on networks of interacting queues is discussed and subsequently, the stability and throughput regions of the system are analyzed and presented. A simple network of two source nodes and two destination nodes is considered first. The broadcast service process is analyzed assuming a channel that allows for packet capture and multipacket reception. In this small network, the stability and throughput regions are observed to coincide. The same problem for a network with N sources and M destinations is considered next. The channel model is simplified in that multipacket reception is no longer permitted. Bounds on the stability region are developed using the concept of stability rank and the throughput region of the system is compared to the bounds. Our results show that as the number of destination nodes increases, the stability and throughput regions diminish. Additionally, a previous conjecture that the stability and throughput regions coincide for a network of arbitrarily many sources is supported for a broadcast scenario by the results presented in this work.
description: 19 pages, 5 figures. Submitted as correspondence to IEEE Transactions on Information Theory, Sept 2006. Revised April 2007
Generalized kinetic equations for charge carriers in graphene
Creators: name: Auslender, M.
name: Katsnelson, M. I.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: A system of generalized kinetic equations for the distribution functions of two-dimensional Dirac fermions scattered by impurities is derived in the Born approximation with respect to short-range impurity potential. It is proven that the conductivity following from classical Boltzmann equation picture, where electrons or holes have scattering amplitude reduced due chirality, is justified except for an exponentially narrow range of chemical potential near the conical point. When in this range, creation of infinite number of electron-hole pairs related to quasi-relativistic nature of electrons in graphene results in a renormalization of minimal conductivity as compared to the Boltzmann term and logarithmic corrections in the conductivity similar to the Kondo effect.
description: final version, Phys. Rev. B, accepted
Recensione di: Giancarla Sola, La formazione originaria. Paideia, humanitas, perfectio, dignitas hominis, Bildung. Bompiani, Milano, 2016
Creators: name: Ammannati, Gianluca
Publisher: name: Ricerche di Pedagogia e Didattica. Journal of Theories and Research in Education
Year: 2018

description: Ricerche di Pedagogia e Didattica. Journal of Theories and Research in Education, V. 13, N. 3 (2018)
On the extraction of weak transition strengths via the (3He,t) reaction at 420 MeV
Creators: name: Zegers, R. G. T
name: Adachi, T.
name: Akimune, H.
name: Austin, Sam M.
name: Berg, A. M. van den
name: Brown, B. A.
name: Fujita, Y.
name: Fujiwara, M.
name: Gales, S.
name: Guess, C. J.
name: Harakeh, M. N.
name: Hashimoto, H.
name: Hatanaka, K.
name: Hayami, R.
name: Hitt, G. W.
name: Howard, M. E.
name: Itoh, M.
name: Kawabata, T.
name: Kawase, K.
name: Kinoshita, M.
name: Matsubara, M.
name: Nakanishi, K.
name: Nakayama, S.
name: Okumura, S.
name: Ohta, T.
name: Sakemi, Y.
name: Shimbara, Y.
name: Shimizu, Y.
name: Scholl, C.
name: Simenel, C.
name: Tameshige, Y.
name: Tamii, A.
name: Uchida, M.
name: Yamagata, T.
name: Yosoi, M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: Differential cross sections for transitions of known weak strength were measured with the (3He,t) reaction at 420 MeV on targets of 12C, 13C, 18O, 26Mg, 58Ni, 60Ni, 90Zr, 118Sn, 120Sn and 208Pb. Using this data, it is shown the proportionalities between strengths and cross sections for this probe follow simple trends as a function of mass number. These trends can be used to confidently determine Gamow-Teller strength distributions in nuclei for which the proportionality cannot be calibrated via beta-decay strengths. Although theoretical calculations in distorted-wave Born approximation overestimate the data, they allow one to understand the main experimental features and to predict deviations from the simple trends observed in some of the transitions.
description: 4 pages, 2 figures
The Effect of Addition of Germanium to the Surface Phenomena in Silver Alloys
Creators: name: Jesiotr, M.
name: Trzaskowski, W.
name: Trochimiak, D.
name: Nawrocki, P.
name: Łukasik, K.
name: Myszka, D.
Publisher: name: The Katowice Branch of the Polish Academy of Sciences
Year: 2018
Subjects: Silver
corrosion
microstructure
Oxide layers
Germanium

description: Archives of Foundry Engineering continues the publishing activity
 started by Foundry Commission of the Polish Academy of Sciences (PAN) in
 Katowice in 1978. The initiator of it was the first Chairman Professor
 Dr Eng. Wacław Sakwa – Corresponding Member of PAN, Honorary Doctor of
 Czestochowa University of Technology and Silesian University of
 Technology. This periodical first name was „Solidification of Metals and
 Alloys” , and made possible to publish the results of works achieved in
 the field of the Basic Problems Research Cooperation. The subject of
 publications was related to the title of the periodical and concerned
 widely understand problems of metals and alloys crystallization in a
 casting mold. In 1978-2000 the 44 issues have been published. Since 2001
 the Foundry Commission has had patronage of the annually published
 “Archives of Foundry” and since 2007 quarterly published “Archives of
 Foundry Engineering”. Thematic scope includes scientific issues of
 foundry industry:

 Theoretical Aspects of Casting Processes,

 Innovative Foundry Technologies and Materials,

 Foundry Processes Computer Aiding,

 Mechanization, Automation and Robotics in Foundry,

 Transport Systems in Foundry,

 Castings Quality Management,

 Environmental Protection.
description: The article describes the impact of germanium on the course of surface phenomena in casting alloys of silver used in gold smithing. The
aim of this works is to describe the assessment of resulting alloys, comparing the area of raw castings and the impact of the addition
content of the alloy on the hardness of the samples. The evaluation also was subject to corrosion resistance of giving a comparison of their
use in relations to traditional silver alloys.
Filling in the Blanks: A Method to Infer the Substructure Membership and Dynamics of 5D Stars
Creators: name: Callingham, Thomas M.
name: Helmi, Amina
Publisher: name: arXiv
Year: 2024
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present and test a method to infer a probability density function (PDF) for the missing vlos of a star with 5D information within $2.5$ kpc. We use stars from the Gaia DR3 RVS catalogue to describe the local orbital structure in action space. This technique also allows us to infer the probability that a 5D star is associated with the Milky Way's stellar Disc or the stellar Halo, which can be further decomposed into known stellar substructures. The method is tested on a 6D Gaia DR3 RVS sample and a 6D Gaia sample crossmatched to groundbased spectroscopic surveys, stripped of their true vlos. The stars predicted vlos, membership probabilities, and inferred structure properties are then compared to the true 6D equivalents, allowing the method's accuracy and limitations to be studied in detail. Our predicted vlos PDFs are statistically consistent with the true vlos, with accurate uncertainties. We find that the vlos of Disc stars can be well constrained, with a median uncertainty of 26 kms. Halo stars are typically less well constrained with a median uncertainty of 72 kms, but those found likely to belong to Halo substructures can be better constrained. The dynamical properties of the total sample and subgroups, such as distributions of integrals of motion and velocities, are also accurately recovered. The group membership probabilities are statistically consistent with our initial labelling, allowing high quality sets to be selected from 5D samples by choosing a trade off between higher expected purity and decreasing expected completeness.
Enhanced activity of massive black holes by stellar capture assisted by a self-gravitating accretion disc
Creators: name: Karas, V.
name: Subr, L.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We study the probability of close encounters between stars from a nuclear cluster and a massive black hole. The gravitational field of the system is dominated by the black hole in its sphere of influence. It is further modified by the cluster mean field (a spherical term) and a gaseous disc/torus (an axially symmetric term) causing a secular evolution of stellar orbits via Kozai oscillations. Intermittent phases of large eccentricity increase the chance that stars become damaged inside the tidal radius of the central hole. Such events can produce debris and lead to recurring episodes of enhanced accretion activity. We introduce an effective loss cone and associate it with tidal disruptions during the high-eccentricity phases of the Kozai cycle. By numerical integration of the trajectories forming the boundary of the loss cone we determine its shape and volume. We also include the effect of relativistic advance of pericentre. The potential of the disc has the efffect of enlarging the loss cone and, therefore, the predicted number of tidally disrupted stars should grow by factor of ~10^2. On the other hand, the effect of the cluster mean potential together with the relativistic pericentre advance act against the eccentricity oscillations. In the end we expect the tidal disruption events to be approximately ten times more frequent in comparison with the model in which the three effects -- the cluster mean field, the relativistic pericentre advance, and the Kozai mechanism -- are all ignored. The competition of different influences suppresses the predicted star disruption rate as the black hole mass increases. Hence, the process under consideration is more important for intermediate-mass black holes, M_bh~10^4M_s.
description: 10 pages, 5 figures; Astronomy & Astrophysics accepted
Effect of in-plane line defects on field-tuned superconductor-insulator transition behavior in homogeneous thin film
Creators: name: Myojin, Kiyokazu
name: Ikeda, Ryusuke
Publisher: name: arXiv
Year: 2007
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Field-tuned superconductor-insulator transition (FSIT) behavior in 2D isotropic and homogeneous thin films is usually accompanied by a nonvanishing critical resistance at low $T$. It is shown that, in a 2D film including line defects paralle to each other but with random positions perpendicular to them, the (apparent) critical resistance in low $T$ limit vanishes, as in the 1D quantum superconducting (SC) transition, under a current parallel to the line defects. This 1D-like critical resistive behavior is more clearly seen in systems with weaker point disorder and may be useful in clarifying whether the true origin of FSIT behavior in the parent superconductor is the glass fluctuation or the quantum SC fluctuation. As a by-product of the present calculation, it is also pointed out that, in 2D films with line-like defects with a long but {\it finite} correlation length parallel to the lines, a quantum metallic behavior intervening the insulating and SC ones appears in the resistivity curves.
description: 16 pages, 14 figures
Implications of "peak oil" for atmospheric CO2 and climate
Creators: name: Kharecha, P. A.
name: Hansen, J. E.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: FOS: Physical sciences

description: Unconstrained CO2 emission from fossil fuel burning has been the dominant cause of observed anthropogenic global warming. The amounts of "proven" and potential fossil fuel reserves are uncertain and debated. Regardless of the true values, society has flexibility in the degree to which it chooses to exploit these reserves, especially unconventional fossil fuels and those located in extreme or pristine environments. If conventional oil production peaks within the next few decades, it may have a large effect on future atmospheric CO2 and climate change, depending upon subsequent energy choices. Assuming that proven oil and gas reserves do not greatly exceed estimates of the Energy Information Administration, and recent trends are toward lower estimates, we show that it is feasible to keep atmospheric CO2 from exceeding about 450 ppm by 2100, provided that emissions from coal, unconventional fossil fuels, and land use are constrained. Coal-fired power plants without sequestration must be phased out before mid-century to achieve this CO2 limit. It is also important to "stretch" conventional oil reserves via energy conservation and efficiency, thus averting strong pressures to extract liquid fuels from coal or unconventional fossil fuels while clean technologies are being developed for the era "beyond fossil fuels". We argue that a rising price on carbon emissions is needed to discourage conversion of the vast fossil resources into usable reserves, and to keep CO2 beneath the 450 ppm ceiling.
description: (22 pages, 7 figures; final version accepted by Global Biogeochemical Cycles)
Fabrication, Dynamics, and Electrical Properties of Insulated SPM Probes for Electrical and Electromechanical Imaging in Liquids
Creators: name: Rodriguez, B. J.
name: Jesse, S.
name: Seal, K.
name: Baddorf, A. P.
name: Kalinin, S. V.
name: Rack, P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Insulated cantilever probes with a high aspect ratio conducting apex have been fabricated and their dynamic and electrical properties analyzed. The cantilevers were coated with silicon dioxide and a via was fabricated through the oxide at the tip apex and backfilled with tungsten to create an insulated probe with a conducting tip. The stiffness and Q-factor of the cantilevers increased after the modifications and their resonances shifted to higher frequencies. The coupling strength between the cantilever and the coating are determined. The applications to conductive and electromechanical imaging of ferroelectric domains are illustrated, and a probe apex repair process is demonstrated.
description: 3 figs
Nonlinear Evolution of Baryon Acoustic Oscillations
Creators: name: Crocce, M.
name: Scoccimarro, R.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We study the nonlinear evolution of the baryon acoustic oscillations (BAO) in the dark matter power spectrum and correlation function using renormalized perturbation theory (RPT). In a previous paper we showed that RPT successfully predicts the damping of acoustic oscillations; here we extend our calculation to the enhancement of power due to mode-coupling. We show that mode-coupling generates additional oscillations that are out of phase with those in the linear spectrum, leading to shifts in the scales of oscillation nodes defined with respect to a smooth spectrum. When Fourier transformed, these out of phase oscillations induce percent-level shifts in the acoustic peak of the two-point correlation function. We present predictions for these shifts as a function of redshift; these should be considered as a robust lower limit to the more realistic case that includes in addition redshift distortions and galaxy bias. We show that these nonlinear effects occur at very large scales, leading to a breakdown of linear theory at scales much larger than commonly thought. We discuss why virialized halo profiles are not responsible for these effects, which can be understood from basic physics of gravitational instability. Our results are in excellent agreement with numerical simulations, and can be used as a starting point for modeling BAO in future observations. To meet this end, we suggest a simple physically motivated model to correct for the shifts caused by mode-coupling.
description: 18 pages, 8 figures, submitted to Phys. Rev. D. v2: We show that mode-coupling introduces out of phase oscillations that lead to shifts in the power spectrum nodes in the method of arXiv:0705.3323
Insights into hyperbolic phonon polaritons in hBN using Raman scattering from encapsulated transition metal dichalcogenide layers
Creators: name: Viner, Jacob J. S.
name: McDonnell, Liam P.
name: Rivera, Pasqual
name: Xu, Xiaodong
name: Smith, David C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: New techniques for probing hyperbolic phonon polaritons (HPP) in 2D materials will support the development of the emerging technologies in this field. Previous reports have shown that it is possible for WSe2 monolayers in contact with the hexagonal boron nitride (hBN) to generate HPP in the hBN via Raman scattering. In this paper, we set out new results on HPP Raman scattering induced in hBN by WSe2 and MoSe2 monolayers including new resonances at which the Raman scattering is enhanced. Analysis of the observed Raman lineshapes demonstrates that Raman scattering allows HPP with wavevectors with magnitudes significantly in excess of 15000 cm-1 to be probed. We present evidence that the Raman scattering can probe HPP with frequencies less than the expected lower bound on the Reststrahlen band suggesting new HPP physics still waits to be discovered.
description: 14 + 10 pages, 5 + 6 figures, in paper + supplementary info
Fast simulation mapping: from standard to modified gravity cosmologies using the bias assignment method
Creators: name: García-Farieta, Jorge Enrique
name: Balaguera-Antolínez, Andrés
name: Kitaura, Francisco-Shu
Publisher: name: arXiv
Year: 2024
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We assess the effectiveness of a non-parametric bias model in generating mock halo catalogues for modified gravity (MG) cosmologies, relying on the distribution of dark matter from either MG or $Λ$CDM. We aim to generate halo catalogues that effectively capture the distinct impact of MG, ensuring high accuracy in both two- and three-point statistics for comprehensive analysis of large-scale structures. As part of this study we aim at investigating the inclusion of MG into non-local bias to directly map the tracers onto $Λ$CDM fields, which would save many computational costs. We employ the bias assignment method (BAM) to model halo distribution statistics by leveraging seven high-resolution COLA simulations of MG cosmologies. Taking into account cosmic-web dependencies when learning the bias relations, we design two experiments to map the MG effects: one utilising the consistent MG density fields and the other employing the benchmark $Λ$CDM density field. BAM generates MG halo catalogues from both calibrations experiments excelling in summary statistics, achieving a $\sim 1\%$ accuracy in the power spectrum across a wide range of $k$-modes, with only minimal differences well below 10\% at modes subject to cosmic variance, particularly below $k<0.07$ $h$Mpc$^{-1}$. The reduced bispectrum remains consistent with the reference catalogues within 10\% for the studied configuration. Our results demonstrate that a non-linear and non-local bias description can model the effects of MG starting from a $Λ$CDM dark matter field.
description: 15 pages, 10 figures, 2 tables
Learning to Control Active Matter
Creators: name: Falk, Martin J
name: Alizadehyazdi, Vahid
name: Jaeger, Heinrich
name: Murugan, Arvind
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The study of active matter has revealed novel non-equilibrium collective behaviors, illustrating their potential as a new materials platform. However, most works treat active matter as unregulated systems with uniform microscopic energy input, which we refer to as activity. In contrast, functionality in biological materials results from regulating and controlling activity locally over space and time, as has only recently become experimentally possible for engineered active matter. Designing functionality requires navigation of the high dimensional space of spatio-temporal activity patterns, but brute force approaches are unlikely to be successful without system-specific intuition. Here, we apply reinforcement learning to the task of inducing net transport in a specific direction for a simulated system of Vicsek-like self-propelled disks using a spotlight that increases activity locally. The resulting time-varying patterns of activity learned exploit the distinct physics of the strong and weak coupling regimes. Our work shows how reinforcement learning can reveal physically interpretable protocols for controlling collective behavior in non-equilibrium systems.
description: 11 pages, 7 figures
Speckle Interferometry of Metal-Poor Stars in the Solar Neighborhood. I
Creators: name: Rastegaev, D. A.
name: Balega, Yu. Yu.
name: Malogolovets, E. V.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We report the results of speckle-interferometric observations of 109 high proper-motion metal-poor stars made with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. We resolve eight objects -- G102-20, G191-55, BD+19$^\circ$~1185A, G89-14, G87-45, G87-47, G111-38, and G114-25 -- into individual components and we are the first to astrometrically resolve seven of these stars. New resolved systems included two triple (G111-38, G87-47) and one quadruple (G89-14) star. The ratio of single-to-binary-to-triple-to-quadruple systems among the stars of our sample is equal to 71:28:6:1.
description: 8 pages, 4 figures, accepted to Astrophysical Bulletin
Divergent paths : Canadian and American labor since the 1930s
Creators: name: Primm, Charles Tiffin
Publisher: name: University of British Columbia
Year: 2010

description: The purpose of this thesis is to determine the major causes of the divergence which has occurred between Canadian and American labor during the past three decades. Employing a comparative case study methodology, I examine the history of the two labor movements during three distinct periods: 1) the formative period for modern industrial relations, roughly 1930-1960; 2) the two decades of divergence, 1960-1980, when Canadian union density grew to nearly double the American level; and 3) the 1980s, a period of major economic restructuring that has witnessed the accelerated decline of American labor while Canadian labor continues to maintain its membership base. I conclude that the primary factors for divergence are: 1) the different political cultures of Canada and the United States; 2) the more favorable labor laws in Canada; and 3) the differences in the ideologies and actions of the unions themselves. During the 1980s, the presence of a relatively strong social democratic movement, better labor legislation, and the rejection of American-style "business unionism" by Canadian unions helps to account for why union density in Canada remains over double the American level.
The 10^5Lsun High-Mass Protostellar Object IRAS23151+5912
Creators: name: Beuther, H.
name: Zhang, Q.
name: Hunter, T. R.
name: Sridharan, T. K.
name: Bergin, E. A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: While most sources above 10^5Lsun have already formed an Ultracompact HII region (UCHII), this is not necessarily the case for sources of lower luminosity. Characterizing sources in the transition phase, i.e., very luminous objects without any detectable free-free emission, is important for a general understanding of massive star formation. Therefore, we observed the luminous High-Mass Protostellar Object IRAS23151+5912 with the Submillimeter Array at 875mum in the submm continuum and spectral line emission at sub-arcsecond resolution. The 875mum submm continuum emission has been resolved into at least two condensations. The previously believed driving source of one of the outflows, the infrared source IRS1, is ~0.9'' offset from the main submm peak. Over the entire 4GHz bandwidth we detect an intermediate dense spectral line forest with 27 lines from 8 different species, isotopologues or vibrationally-torsionally excited states. Temperature estimates based on the CH3OH line series result in values of T(Peak1)~150+-50K and T(Peak2)~80~30K for the two submm peak positions, respectively. The SiO(8-7) red- and blue-shifted line maps indicate the presence of two molecular outflows. In contrast, the vibrationally-torsionally excited CH3OH line exhibits a velocity gradient approximately perpendicular to one of the outflows. With a size of approximately 5000AU and no Keplerian rotation signature, this structure does not resemble a genuine accretion disk but rather a larger-scale rotating toroid that may harbor a more common accretion disk at its so far unresolved center.
description: 9 pages, 7 figures, accepted for Astronomy and Astrophysics
Expected Gamma-Ray Burst Detection Rates and Redshift Distributions for the BlackCAT CubeSat Mission
Creators: name: Colosimo, Joseph M.
name: Fox, Derek B.
name: Falcone, Abraham D.
name: Palmer, David M.
name: Hancock, Frederic
name: Betts, Michael
name: Bevidas, William A.
name: Buffington, Jacob C.
name: Burrows, David N.
name: Catlin, Zachary E.
name: Emeigh, Timothy
name: Forstmeier, Thomas
name: Nizam, Kadri M.
name: Reichard, Collin
name: Scigliani, Ana C.
name: Stone, Lukas R.
name: Thornton, Ian
name: Wages, Mitchell
name: Washington, Daniel
name: Zugger, Michael E.
Publisher: name: arXiv
Year: 2024
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We report the results of an extensive set of simulations exploring the sensitivity of the BlackCAT CubeSat to long-duration gamma-ray bursts (GRBs). BlackCAT is a NASA APRA-funded CubeSat mission for the detection and real-time sub-arcminute localization of high-redshift ($z\gtrsim 3.5$) GRBs. Thanks to their luminous and long-lived afterglow emissions, GRBs are uniquely valuable probes of high-redshift star-forming galaxies and the intergalactic medium. In addition, each detected GRB with a known redshift serves to localize a region of high-redshift star formation in three dimensions, enabling deep follow-on searches for host galaxies and associated local and large-scale structures. We explore two distinct models for the GRB redshift distribution and luminosity function, both consistent with Swift observations. We find that, for either model, BlackCAT is expected to detect a mean of 42 bursts per year on-orbit, with 6.7% to 10% of these at $z>3.5$. BlackCAT bursts will be localized to $r_{90} \lesssim 55^{\prime\prime}$ precision and reported to the community within seconds. Due to the mission orbit and pointing scheme, bursts will be located in the night sky and well-placed for deep multiwavelength follow-up observations. BlackCAT is on schedule to achieve launch readiness in 2025.
description: 10 pages, 4 figures, 3 tables; Published in ApJ
Extremely Long-Lived Charged Massive Particles as A Probe for Reheating of the Universe
Creators: name: Takayama, Fumihiro
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss the impact of charged massive particle big bang nucleosynthesis(CBBN) to explore the nature of the reheating of the Universe in the case that a new extremely long-lived charged massive particle(CHAMP) exists. If the mass of the CHAMP is within collider reach and it's lifetime is longer than $10^4$sec, the comparison between the CBBN prediction and observed $^6$Li abundances may indicate nonstandard reheating in the early Universe without relying on details of the decay properties. Even if the CHAMP mass is outside the reach of colliders, the cosmological considerations may provide a nontrivial hint for the existence of such very heavy long-lived CHAMPs from the late Universe if the daughter particles are the dominant component of the present dark matter. We consider a low reheating temperature model as an example of the nonstandard reheating scenarios.
description: 7 pages, 2 figures, published in Physical Review D
title: Schülerinnen & Schüler im luxemburgischen Schulsystem
Creators: name: Backes, Susanne
name: Lenz, Thomas
Publisher: name: Luxembourg Centre for Educational Testing (LUCET) & Service de Coordination de la Recherche et de l’Innovation pédagogiques et technologiques (SCRIPT)
Year: 2021

description: Nationaler Bildungsbericht Luxemburg 2021