cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
An efficient one-pot synthesis of highly functionalized selenophenes
Creators: name: Vojdani, Zeinab
name: Mosslemin, Mohammad H.
name: Mohebat, Razieh
name: Hassanabadi, Alireza
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Biophysics
subject: Biochemistry
subject: 29999 Physical Sciences not elsewhere classified
subject: FOS: Physical sciences
subject: Medicine
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 111714 Mental Health
subject: FOS: Health sciences

description: The reaction between active alkenes such as 2-pyridin-2-yl-methylene-malononitrile or ethyl-2-cyano-3-pyridin-2-yl-acrylate and acetylenic esters in the presence of KSeCN at room temperature provided a simple and efficient one-pot route for the synthesis of highly functionalized selenophenes. The reaction is characterized by mild conditions, short reaction time and tolerance to various functional groups and the products were fully characterized by multinuclear (1H, 13C, and 77Se) NMR spectroscopy.
Darboux transformations of Jacobi matrices and Padé approximation
Creators: name: Derevyagin, Maxim
name: Derkach, Vladimir
Publisher: name: arXiv
Year: 2010
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: Mathematical Physics (math-ph)
subject: Spectral Theory (math.SP)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: Primary 47B36, Secondary 30E05, 42C05

description: Let J be a monic Jacobi matrix associated with the Cauchy transform F of a probability measure. We construct a pair of the lower and upper triangular block matrices L and U such that J=LU and the matrix J_c=UL is a monic generalized Jacobi matrix associated with the function F_c(z)=zF(z)+1. It turns out that the Christoffel transformation J_c of a bounded monic Jacobi matrix J can be unbounded. This phenomenon is shown to be related to the effect of accumulating at infinity of the poles of the Padé approximants of the function F_c although F_c is holomorphic at infinity. The case of the UL-factorization of J is considered as well.
description: 28 pages (some typos are corrected)
Against the coup : Mídia NINJA and the fight for democracy in Brazil
Creators: name: Teixeira Castro Corrêa, João Vitor
Publisher: name: University of British Columbia
Year: 2017

description: The impeachment of Brazil’s former president Dilma Rousseff on August 31, 2016 points to the end of a cycle in Brazilian politics (Domingues, 2016). Many Brazilians have lost their trust in institutional politics, and no longer feel represented (Barbosa, 2015; Barbosa et al, 2016; Da Luz, 2015; Domingues, 2016; Friedman, E. J. & Hochstetler, K., 2002). In a sense, it is a clash of the new Brazil with the old (Ituassu, 2013). A series of mass demonstrations have taken the streets of Brazil since 2013, representing the tipping point of a new wave of social movements in the country (Telles, 2016). New opportunities arise for civil disobedience and experimentation, and social media has been deemed as playing a crucial role in this ongoing process — a counter-narrative to traditional, Brazilian mainstream media, and a successful venue for connecting civil society to the political sphere (Ituassu, 2013). Among the groups that have emerged as key actors during this recent period of protests is Mídia NINJA, a reference to ancient Japanese warriors and an acronym for Independent Narratives Journalism and Action, a non-corporate, non-profit media group run by citizen journalists spread across over 100 cities in Brazil (Mídia NINJA, n.d.), with more than 2,000 collaborators. Armed with smartphones and video cameras, the group has sought to shape the news agenda by engaging millions of people online and articulating a counter-narrative to corporate media. This research project explores how the new online media ecology, made possible by the advent of the Internet, disrupts and inaugurate new possibilities for journalism, civic engagement and social justice activism through a case study of Mídia NINJA, utilizing both computational and manual methods of data gathering and interpretation (Hermida et al., 2013).
Update on tests of the Cen A neutron-emission model of highest energy cosmic rays
Creators: name: Anchordoqui, Luis A.
name: Goldberg, Haim
name: Weiler, Thomas J.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We propose that neutron emission from Cen A dominates the cosmic ray sky at the high end of the spectrum. Neutrons that are able to decay generate proton diffusion fronts, whereas those that survive decay produce a spike in the direction of the source. We use recent data reported by the Pierre Auger Collaboration to normalize the injection spectrum and estimate the required luminosity in cosmic rays. We find that such a luminosity, L_{CR} ~ 5 x 10^{40} erg/s, is considerably smaller than the bolometric luminosity of Cen A, L_{bol} ~ 10^{43} erg/s. We compute the incoming current flux density as viewed by an observer on Earth and show that the anisotropy amplitude is in agreement with data at the 1σlevel. Regardless of the underlying source model, our results indicate that after a decade of data taking the Pierre Auger Observatory will be able to test our proposal.
description: To be published in PRD
XORIJIY OMMAVIY AXBOROT VOSITALARINING MEDIA MAKONDAGI O'RNI
Creators: name: Axmadjanova Muazzam Islomjanovna Namangan davlat pedagogika instituti stajyor-o'qituvchisi Sobirjonova Shaxnoza Shuhrat qizi Namangan davlat pedagogika instituti 1-kurs talabasi
Publisher: name: Zenodo
Year: 2025

description: Maqolada xorijiy ommaviy axborot vositalarining (OAV) global mediamakondagi o‘rni, ularning axborot tarqatish, jamoatchilik fikriga ta’siri va xalqaro munosabatlardagi roli tahlil qilinadi. Shuningdek, ularning raqamli texnologiyalar davridagi rivojlanishi, media manipulyatsiya va dezinformatsiya masalalari yoritiladi.

Kalit so‘zlar: Xorijiy OAV, mediamakon, axborot tarqatish, jamoatchilik fikri, xalqaro munosabatlar, raqamli texnologiyalar, media manipulyatsiya, dezinformatsiya.
An ultra-sound assisted synthesis of α-aminophosphonates from benzyl halides via sequential Kornblum and Kabachnik-fields reaction
Creators: name: Amin, Rabia
name: Ara, Tabassum
Publisher: name: Taylor & Francis
Year: 2022
Subjects: subject: Biochemistry
subject: Genetics
subject: FOS: Biological sciences
subject: Biotechnology
subject: Developmental Biology

description: An ultrasound-assisted simple, easy and straightforward method for the synthesis of α-aminophosphonates has been developed via Kornblum/Kabachnik-fields reaction. The method involves in situ generation of an aldehyde intermediate from benzyl halides via oxidative dehalogenation followed by coupling with aryl amine and trialkyl phosphite in a one-pot three component manner under ultrasonic irradiations. The developed method is compatible with various functionalities and the desired products are obtained in good to excellent yield under mild conditions.
Comparing cavity and ordinary laser cooling within the Lamb-Dicke regime
Creators: name: Blake, Tony
name: Kurcz, Andreas
name: Beige, Almut
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Cavity-mediated cooling has the potential to become one of the most efficient techniques to cool molecular species down to very low temperatures. In this paper we analyse cavity cooling with single-laser driving for relatively large cavity decay rates kappa and relatively large phonon frequencies nu. It is shown that cavity cooling and ordinary laser cooling are essentially the same within the validity range of the Lamb-Dicke approximation. This is done by deriving a closed set of rate equations and calculating the corresponding stationary state phonon number and cooling rate. For example, when nu is either much larger or much smaller than kappa, the minimum stationary state phonon number scales as kappa^2/16 nu^2 (strong confinement regime) and as kappa / 4 nu (weak confinement regime), respectively.
description: 12 pages, 8 figures, final version accepted for publication
title:  Venezuela y el Éxodo Científico y Profesional: Un análisis a los Programas Internacionales de Apoyo a Científicos, Académicos y Profesionales Venezolanos en el Exilio, Refugiados y en Riesgo
Creators: name: Castillo, Ruth
Publisher: name: RomaTrE-Press
Year: 2019

description: L'esilio di accademici e scienziati venezuelani rappresenta un disastro per una comunità emergente e giovane all'interno del Paese. L'abbandono della comunità accademica venezuelana in esilio può portare a una disconnessione, perdita e isolamento della Scienza venezuelana – formatasi prima e durante i primi anni del periodo totalitario – all'interno del contesto nazionale e internazionale.
description: Democrazia e Sicurezza – 2018, n. 4
title:  Zone grigie e zone rosse: la capacità delle circolari di incidere sulla sfera giuridica individuale e di limitare le libertà
Creators: name: Ugolini, Fulvia
Publisher: name: RomaTrE-Press
Year: 2019

description: Questo articolo si occupa dell'uso sempre più ampio di circolari governative e ministeriali come fonte di diritto nel quadro dei diritti dei migranti volta ad affrontare le preoccupazioni relative alla sicurezza. Poiché le circolari non si qualificano come fonte di diritto primario né secondario, né come fonti normative, è problematico che il loro uso attuale incida sui diritti e sulle libertà individuali costituzionalmente tutelati. Una panoramica delle precedenti adozioni di tali documenti contribuirà a delineare una politica governativa che probabilmente si rivolge ai diritti dei migranti, e in particolare ai richiedenti asilo, con l'uso coerente di circolari vincolanti. Per quanto riguarda l'attuale situazione italiana, questo articolo analizza gli aspetti più rilevanti di due circolari assai recenti adottate dai Prefetti di Bologna e Firenze – le cosiddette 'Circolari delle zone rosse' – e precisamente le restrizioni alla libertà di movimento e di determinazione dei soggetti interessati dalle disposizioni delle circolari. Il presente studio si propone di gettare nuova luce sulla prassi esistente di limitare le libertà personali e le garanzie costituzionali mediante documenti inadeguati, e tecnicamente non normativi, e di fornire le basi per future discussioni sulla compatibilità delle circolari esaminate con le principali disposizioni della Costituzione della Repubblica Italiana.
description: Democrazia e Sicurezza – 2018, n. 4
Proposing lead compounds for the development of SARS-CoV-2 receptor-binding inhibitors
Creators: name: Awuni, Elvis
name: Musah, Radiatu Abdallah
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Biophysics
subject: Biochemistry
subject: Medicine
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Immunology
subject: FOS: Clinical medicine
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: Cancer
subject: 110309 Infectious Diseases
subject: FOS: Health sciences

description: The COVID-19 pandemic has had deleterious effects on the world and demands urgent measures to find therapeutic agents to combat the current and related future outbreaks. The entry of SARS-CoV-2 into the host’s cell is facilitated by the interaction between the viral spike receptor-binding domain (sRBD) and the human angiotensin-converting enzyme 2 (hACE2). Although the interface of sRBD involved in the sRBD-hACE2 interaction has been projected as a primary vaccine and drug target, currently no small-molecule drugs have been approved for covid-19 treatment targeting sRBD. Herein structure-based virtual screening and molecular dynamics (MD) simulation strategies were applied to identify novel potential small-molecule binders of the SARS-CoV-2 sRBD from an sRBD-targeted compound library as leads for the development of anti-COVID-19 drugs. The library was initially screened against sRBD by using the GOLD docking program whereby 19 compounds were shortlisted based on docking scores after using a control compound to set the selection cutoff. The stability of each compound in MD simulations was used as a further standard to select four hits namely T4S1820, T4589, E634-1449, and K784-7078. Analyses of simulations data showed that the four compounds remained stably bound to sRBD for ≥ 80 ns with reasonable affinities and interacted with pharmacologically important amino acid residues. The compounds exhibited fair solubility, lipophilicity, and toxicity-propensity characteristics that could be improved through lead optimization regimes. The overall results suggest that the scaffolds of T4S1820, E634-1449, and K784-7078 could serve as seeds for developing potent small-molecule inhibitors of SARS-CoV-2 receptor binding and cell entry. Communicated by Ramaswamy H. Sarma
Topologically non-trivial superconductivity in spin-orbit coupled systems: Bulk phases and quantum phase transitions
Creators: name: Tewari, Sumanta
name: Stanescu, Tudor D.
name: Sau, Jay D.
name: Sarma, S. Das
Publisher: name: arXiv
Year: 2010
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Topologically non-trivial superconductivity has been predicted to occur in superconductors with a sizable spin-orbit coupling in the presence of an external Zeeman splitting. Two such systems have been proposed: (a) s-wave superconductor pair potential is proximity induced on a semiconductor, and (b) pair potential naturally arises from an intrinsic s-wave pairing interaction. As is now well known, such systems in the form of a 2D film or 1D nano-wires in a wire-network can be used for topological quantum computation. When the external Zeeman splitting $Γ$ crosses a critical value $Γ_c$, the system passes from a regular superconducting phase to a non-Abelian topological superconducting phase. In both cases (a) and (b) we consider in this paper the pair potential $Δ$ is strictly s-wave in both the ordinary and the topological superconducting phases, which are separated by a topological quantum critical point at $Γ_c = \sqrt{Δ^2 + μ^2}$, where $μ(>> Δ)$ is the chemical potential. On the other hand, since $Γ_c >> Δ$, the Zeeman splitting required for the topological phase ($Γ> Γ_c$) far exceeds the value ($Γ\sim Δ$) above which an s-wave pair potential is expected to vanish (and the system to become non-superconducting) in the absence of spin-orbit coupling. We are thus led to a situation that the topological superconducting phase appears to set in a parameter regime at which the system actually is non-superconducting in the absence of spin-orbit coupling. In this paper we address the question of how a pure s-wave pair potential can survive a strong Zeeman field to give rise to a topological superconducting phase. We show that the spin-orbit coupling is the crucial parameter for the quantum transition into and the robustness of the topologically non-trivial superconducting phase realized for $Γ>> Δ$.
description: as published in the focus issue on Topological Quantum Computation, New J. Phys. 13 (2011)
title: PLUXIN: micro- and macroplastic sampling and concentrations to initiate the 2DH plastic dispersal model
Creators: name: Bouwens, Jan
name: Asselman, Jana
name: Janssen, Colin
name: Vercauteren, Maaike
name: Teunkens, Bert
name: Catarino, Ana
name: Everaert, Gert
Publisher: name: Flanders Marine Institute
Year: 2021

description: Title : Volume : Issue : Pagination : 35
Dynamic Transitions for Quasilinear Systems and Cahn-Hilliard equation with Onsager mobility
Creators: name: Liu, Honghu
name: Sengul, Taylan
name: Wang, Shouhong
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 76E06, 35Q35, 35B36

description: The main objectives of this article are two-fold. First, we study the effect of the nonlinear Onsager mobility on the phase transition and on the well-posedness of the Cahn-Hilliard equation modeling a binary system. It is shown in particular that the dynamic transition is essentially independent of the nonlinearity of the Onsager mobility. However, the nonlinearity of the mobility does cause substantial technical difficulty for the well-posedness and for carrying out the dynamic transition analysis. For this reason, as a second objective, we introduce a systematic approach to deal with phase transition problems modeled by quasilinear partial differential equation, following the ideas of the dynamic transition theory developed recently by Ma and Wang.
Two-dimensional topological insulators in quantizing magnetic fields
Creators: name: Tkachov, G.
name: Hankiewicz, E. M.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Two-dimensional topological insulators are characterized by gapped bulk states and gapless helical edge states, i.e. time-reversal symmetric edge states accommodating a pair of counter-propagating electrons. An external magnetic field breaks the time-reversal symmetry. What happens to the edge states in this case? In this paper we analyze the edge-state spectrum and longitudinal conductance in a two-dimensional topological insulator subject to a quantizing magnetic field. We show that the helical edge states exist also in this case. The strong magnetic field modifies the group velocities of the counter-propagating channels which are no longer identical. The helical edge states with different group velocities are particularly prone to get coupled via backscattering, which leads to the suppression of the longitudinal edge magnetoconductance.
description: to appear in Physica E "Special Issue: Topological Insulators"
Bulk viscosity of the massive Gross-Neveu model
Creators: name: Fernandez-Fraile, Daniel
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Superconductivity (cond-mat.supr-con)
subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A calculation of the bulk viscosity for the massive Gross-Neveu model at zero fermion chemical potential is presented in the large-$N$ limit. This model resembles QCD in many important aspects: it is asymptotically free, has a dynamically generated mass gap, and for zero bare fermion mass it is scale invariant at the classical level (broken through the trace anomaly at the quantum level). For our purposes, the introduction of a bare fermion mass is necessary to break the integrability of the model, and thus to be able to study momentum transport. The main motivation is, by decreasing the bare mass, to analyze whether there is a correlation between the maximum in the trace anomaly and a possible maximum in the bulk viscosity, as recently conjectured. After numerical analysis, I find that there is no direct correlation between these two quantities: the bulk viscosity of the model is a monotonously decreasing function of the temperature. I also comment on the sum rule for the spectral density in the bulk channel, as well as on implications of this analysis for other systems.
description: v2: 3->3 processes included, conclusions unchanged. Comments and references added. Typos corrected. To appear in Phys. Rev. D
Core-halo distribution in the Hamiltonian Mean-Field Model
Creators: name: Pakter, Renato
name: Levin, Yan
Publisher: name: arXiv
Year: 2010
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We study a paradigmatic system with long-range interactions: the Hamiltonian Mean-Field Model (HMF). It is shown that in the thermodynamic limit this model does not relax to the usual equilibrium Maxwell-Boltzmann distribution. Instead, the final stationary state has a peculiar core-halo structure. In the thermodynamic limit, HMF is neither ergodic nor mixing. Nevertheless, we find that using dynamical properties of Hamiltonian systems, it is possible to quantitatively predict both the spin distribution and the velocity distribution functions in the final stationary state, without any adjustable parameters. We also show that HMF undergoes a non-equilibrium first-order phase transition between paramagnetic and ferromagnetic states.
Exact dynamics and decoherence of two cold bosons in a 1D harmonic trap
Creators: name: Sowinski, Tomasz
name: Brewczyk, Miroslaw
name: Gajda, Mariusz
name: Rzazewski, Kazimierz
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We study dynamics of two interacting ultra cold Bose atoms in a harmonic oscillator potential in one spatial dimension. Making use of the exact solution of the eigenvalue problem of a particle in the delta-like potential we study time evolution of initially separable state of two particles. The corresponding time dependent single particle density matrix is obtained and diagonalized and single particle orbitals are found. This allows to study decoherence as well as creation of entanglement during the dynamics. The evolution of the orbital corresponding to the largest eigenvalue is then compared to the evolution according to the Gross-Pitaevskii equation. We show that if initially the center of mass and relative degrees of freedom are entangled then the Gross-Pitaevskii equation fails to reproduce the exact dynamics and entanglement is produced dynamically. We stress that predictions of our study can be verified experimentally in an optical lattice in the low-tunneling limit.
description: 9 figures, 5 movies available on-line
Analysis of low-noise EEG in search of functional gamma band correlates
Creators: name: Hamzei, Nazanin
Publisher: name: University of British Columbia
Year: 2017

description: The electroencephalogram (EEG) has proven to be a useful information source in analysis of brain activity, diagnosis of neurological disorders, and development of brain-computer interfaces (BCI’s). Through numerous studies over the past decades, EEG activity in different frequency bands has been observed to correspond with various mental states. Clinical use of EEG, however, is often limited to frequency ranges below 30 Hz, ignoring potentially informative patterns within the gamma band (30-100 Hz). Indeed, the gamma band has received greater scrutiny in recent years and is typically known to underlie and be modulated by sensorimotor behaviors and internal cognitive processes. In this study, we have investigated the potential of an ultra-low noise capsule at the LSBB (Laboratoire Souterrain a Bas Bruit, Rustrel, France) for acquisition of clean EEG signals, with a focus on analysis of high frequencies (gamma band) in search for novel activity patterns. Using a battery-operated EEG acquisition system, we acquired 64-channel EEG recordings from a few volunteers performing several cognitive, sensory, and motor tasks in both LSBB and a typical research laboratory. Upon analysis of this data using Stockwell Transform, we compared task-specific gamma band energy increases of signals acquired at the two environments, observing more prominent functional EEG changes in LSBB. Moreover, we studied all recordings in both environments to examine statistically significant spatial and spectral correlates of spontaneous EEG pertaining to each of the tasks. To further assess the task-induced changes in the EEG signals, we have also proposed a framework for analyzing gamma band connectivity; i.e. functional patterns of interaction between distinct channels of the EEG. Using this framework, we have analyzed directional connectivity on recordings pertaining to motor tasks, both in a batch-based (yielding a time-averaged pattern) and an instantaneous manner. Batch-based connectivity analysis of the data resulted in well-defined connectivity patterns among subjects, while instantaneous connectivity analysis was inconsistent due to limitations of the study protocol. The results obtained in this thesis demonstrate the potential of the low-noise capsule and motivate further protocol enhancements and analysis methods for conducting high-frequency EEG studies at LSBB.
The intergalactic medium over the last 10 billion years II: Metal-line absorption and physical conditions
Creators: name: Oppenheimer, Benjamin D.
name: Davé, Romeel
name: Katz, Neal
name: Kollmeier, Juna A.
name: Weinberg, David H.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We investigate the metallicity evolution and content of the intergalactic medium (IGM) and galactic halo gas from z=2->0 using 110-million particle cosmological hydrodynamic simulations. We focus on the detectability and physical properties of UV resonance metal-line absorbers observable with Hubble's Cosmic Origins Spectrograph (COS). We confirm that galactic superwind outflows are required to enrich the IGM to observed levels down to z=0 using three wind prescriptions contrasted to a no-wind simulation. Our favoured momentum-conserved wind prescription deposits metals closer to galaxies owing to its moderate energy input, while the more energetic constant wind model enriches the warm-hot IGM 6.4x more. Despite these significant differences, all wind models produce metal-line statistics within a factor of two of existing observations. This is because OVI, CIV, SiIV, and NeVIII absorbers primarily arise from T<10^5 K, photo-ionised gas that is enriched to similar levels in the three feedback schemes. OVI absorbers trace the diffuse phase with delta<100, which is enriched to ~1/50 Zsol at z=0, although the absorbers themselves usually exceed 0.3 Zsol and arise from inhomogeneously distributed, un-mixed winds. CIV and SiIV absorbers trace primarily T~10^4 K gas inside haloes. We predict COS will observe a population of NeVIII photo-ionised absorbers tracing T<10^5 K, delta~10 gas. MgX and SiXII are rarely detected in COS S/N=30 simulated sight lines although detections trace T=10^(6-7) K halo gas. In general, the IGM is enriched in an outside-in manner, where wind-blown metals released at higher redshift reach lower overdensities, resulting in higher ionisation species tracing lower-density, older metals. At z=0, the 90% of baryons outside of galaxies are enriched to 0.096 Zsol, but the 65% of unbound baryons in the IGM have 0.018 Zsol and contain only 4% of all metals.
description: Accepted to MNRAS, 34 pages, 21 figures, 3 tables
Search for the Rare Decay B->K nu nubar
Creators: name: The BABAR Collaboration
name: Sanchez, P. del Amo
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We present a search for the rare decays B+ -> K+ nu nubar and B0 -> K0 nu nubar using 459 million BBbar pairs collected with the BaBar detector at the SLAC National Accelerator Laboratory. Flavor-changing neutral-current decays such as these are forbidden at tree level but can occur through one-loop diagrams in the Standard Model (SM), with possible contributions from new physics at the same order. The presence of two neutrinos in the final state makes identification of signal events challenging, so reconstruction in the semileptonic decay channels B -> D(*) l nu of the B meson recoiling from the signal B is used to suppress backgrounds. We set an upper limit at the 90% confidence level of 1.3 x 10^{-5} on the total branching fraction for B+ -> K+ nu nubar, and 5.6 x 10^{-5} for B0 -> K0 nu nubar. We additionally report partial branching fractions in two ranges of di-neutrino mass squared for B+ -> K+ nu nubar.
description: 10 pages, 6 postscript figures
title:  Verso una memoria autocritica: ripensare i racconti e i ricordi degli “anni di piombo”
Creators: name: Musolino  ,  Santina
Publisher: name: RomaTrE-Press
Year: 2019

description: Il contributo – inserito nel quadro teorico della sociologia della memoria e dei cultural studies – analizza le rappresentazioni culturali della violenza politica che hanno caratterizzato gli anni Settanta e i primi Ottanta in Italia, e il ruolo di tali rappresentazioni rispetto ai tentativi di costruire una memoria pubblica e condivisa di quegli eventi. Adottando il paradigma del trauma proposto da Jeffrey Alexander (2004, 2006), si osserverà come la mancata capacità della società italiana di affrontare questo passato traumatico abbia favorito la perpetrazione di «ricordi conflittuali» (Hajek 2010) o addirittura la determinazione di una sorta di «amnesia difensiva» (Glynn 2006) e di «strategie di rimozione» che sembrano permeare la produzione culturale italiana.
description: Democrazia e Sicurezza – 2018, n. 4
Exciton Transport and Andreev Reflection in a Bilayer Quantum Hall System
Creators: name: Finck, A. D. K.
name: Eisenstein, J. P.
name: Pfeiffer, L. N.
name: West, K. W.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We demonstrate that counterflowing electrical currents can move through the bulk of the excitonic quantized Hall phase found in bilayer two-dimensional electron systems (2DES) even as charged excitations cannot. These counterflowing currents are transported by neutral excitons which are emitted and absorbed at the inner and outer boundaries of an annular 2DES sample via an Andreev reflection process.
description: 4+ pages, 4 figures. Revised version as accepted for publication in Physical Review Letters
Dark energy as a curvature of space-time induced by quantum vacuum fluctuations
Creators: name: Santos, Emilio
Publisher: name: arXiv
Year: 2010
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: It is shown that quantum vacuum fluctuations give rise to a curvature of space-time of the order appropriate to explain the observed accelerated expansion of the universe. The fact that the fluctuations produce curvature, even if the expectation of the vacuum energy vanishes, is a consequence of the non-linear character of the Einstein equation. A calculation is made, involving plausible hypotheses within quantized gravity, which establishes a relation between the two-point correlation of the vacuum fluctuations and the space-time curvature.
description: Accepted in Astrophysics and Space Science
The maximal linear extension theorem in second order arithmetic
Creators: name: Marcone, Alberto
name: Shore, Richard A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Logic (math.LO)
subject: FOS: Mathematics
subject: 03B30 (Primary) 06A07 (Secondary)

description: We show that the maximal linear extension theorem for well partial orders is equivalent over RCA_0 to ATR_0. Analogously, the maximal chain theorem for well partial orders is equivalent to ATR_0 over RCA_0.
description: 18 pages. New proof of the maximal chain theorem in ATR_0
Identification of novel estrogen receptor inhibitors for the treatment of hormone resistant breast cancer
Creators: name: Singh, Kriti
Publisher: name: University of British Columbia
Year: 2017

description: Estrogen receptor alpha positive (ERα+) disease constitutes approximately 75% of all breast cancer (BCa) cases. However resistance to hormone therapy is observed in early-stage as well as in metastatic disease. Importantly, 70% of ERα+ primary tumors retain active ERα when they metastasize and, therefore, ERα continues to play a role in the resistant form of the disease. Moreover, the effectiveness of conventional hormone therapies is hampered due to gain-of-function mutations that may render the receptor constitutively active. Thus drugs that target the ERα estrogen binding site can become ineffective with time. Moreover, cross-talk between ERα and activated growth factor receptors, or their downstream kinases have shown to play a major role in activating ERα even in the absence of estradiol. Taken together, these observations highlight the importance of developing therapeutics that target alternative sites on the receptor, for instance, those that directly act on the co-activator binding pocket called activation function-2 (AF2) site. Using methods of in-silico screening followed by a systematic computer-guided lead optimization process, we were able to develop several promising small-molecule inhibitors that target the AF2 functional site of ERs. This thesis describes the establishment of an experimental pipeline and development of such inhibitors. The identified lead compound VPC-16606 effectively blocked ERα-co-activator interactions, demonstrated a strong anti-proliferative effect against a panel of ERα+ cells including Tamoxifen-resistant cells and down-regulated ERα-dependent genes. Most importantly, VPC-16606 successfully inhibited known constitutively active mutant forms of ERα observed in clinical settings where BCa patients have relapsed on aromatase inhibitors. Furthermore, the compound also reduced tumor burden in vivo. Overall, these studies helped to identify a novel class of ERα AF2 inhibitors which have the potential to effectively inhibit ERα activity by a unique mechanism and to circumvent the issue of hormone resistance in BCa patients.
Frontloading in der Produktentwicklung von Power-Tools durch frühe Validierung mit Hilfe von leistungsskalierten Prototypen
Creators: name: Matthiesen, Sven
name: Gwosch, Thomas
name: Mangold, Sebastian
name: Grauberger, Patric
name: Steck, Michael
name: Cersowsky, Stefan
Publisher: name: Karlsruhe
Year: 2017
Subjects: Frontloading
Testing
Power-Tools
Leistungsskalierung
Prototypen
HiL
IPEK-XiL
Methodenentwicklung

description: Derzeit geschieht Frontloading, also der frühe Erkenntnisgewinn, in der Produktentwicklung häufig simulativ über Berechnungstools, durch Rapid-Prototyping und durch den Einsatz von Hardware-Prüfständen. Während Simulationen oft komplexe Modelle erfordern, ist der Einsatz von Prototypen aus Rapid-Prototyping Verfahren bislang oft auf Grund der limitierten Beanspruchbarkeit sowohl in Prüfständen, als auch frühen Funktionstests nur eingeschränkt möglich. Ziel der hier vorgestellten IPEK-sCiL-Methode ist es, eine Validierungsmethode für Prototypen mit geringer Beanspruchbarkeit bereitzustellen. Der Einsatz von leistungsskalierten Prototypen soll im Vorgängerprodukt durch eine Skalierung des Leistungsflusses auf HiL-Plattformen ermöglicht werden. Die Methode wird am Beispielsystem Akkubohrschrauber zur Untersuchung von leistungsskalierten Prototypen der Sperrkörperkupplung gezeigt.",
Effects of Ultraviolet Background and Local Stellar Radiation on the H_I Column Density Distribution
Creators: name: Nagamine, Kentaro
name: Choi, Jun-Hwan
name: Yajima, Hidenobu
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We study the impact of ultraviolet background (UVB) radiation field and the local stellar radiation on the H_I column density distribution f(N_HI) of damped Ly-alpha systems (DLAs) and sub-DLAs at z=3 using cosmological smoothed particle hydrodynamics simulations. We find that, in the previous simulations with an optically thin approximation, the UVB was sinking into the H_I cloud too deeply, and therefore we underestimated the f(N_HI) at 19 < log(N_HI) < 21.2 compared to the observations. If the UVB is shut off in the high-density regions with n_gas > 6 x 10^{-3} cm^{-3}, then we reproduce the observed f(N_HI) at z=3 very well. We also investigate the effect of local stellar radiation by post-processing our simulation with a radiative transfer code, and find that the local stellar radiation does not change the f(N_HI) very much. Our results show that the shape of f(N_HI) is determined primarily by the UVB with a much weaker effect by the local stellar radiation and that the optically thin approximation often used in cosmological simulation is inadequate to properly treat the ionization structure of neutral gas in and out of DLAs. Our result also indicates that the DLA gas is closely related to the transition region from optically-thick neutral gas to optically-thin ionized gas within dark matter halos.
description: 5 pages, 3 figures, uses emulateapj. ApJL in press. Corrected a plotting error in Fig. 3, which reduced the effect of local stellar radiation on f(N_HI)
Disappearing in plain sight : an exploratory study of co-occurring eating and substance abuse dis/orders among homeless youth in Vancouver, Canada
Creators: name: Luongo, Nicole Marie
Publisher: name: University of British Columbia
Year: 2017

description: How are disordered eating and substance abuse embodied, experienced, and articulated within a context of multi-dimensional marginalization? Existing studies that address this question emphasize medical influences and gather clinical samples, thereby overlooking those for whom structural constraints such as poverty make accessing costly and time-intensive treatment unrealistic. In this study, I fill methodological and empirical gaps in the literature by using qualitative methods to explore the co-occurrence of eating and substance use disorders among homeless youth. This study consists of two parts: (1) semi-structured interviews with youth and (2) structured interviews with key informants employed by low-barrier support services. Results show several indicators of co-occurring disordered eating and substance abuse among homeless youth. There is a strong link between conscious self-starvation due to body image concerns and compensatory substance abuse behaviours, while youth also engage in substance abuse to mitigate the effects of hunger related to food insecurity. Further, there is a significant disparity when comparing youths’ eating disorder and food-related health literacy to their substance use disorder health literacy. Finally, patterned responses among youth and front-line workers suggest that while service providers have several supports in place to assist youth who are engaging in problematic substance use, there is a shortage of existing infrastructure to assist youth who are struggling with disordered eating. I conclude by offering suggestions for further research on co-occurring eating and substance abuse disorders among vulnerable populations.
Non-linear dark energy clustering
Creators: name: Anselmi, Stefano
name: Ballesteros, Guillermo
name: Pietroni, Massimo
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider a dark energy fluid with arbitrary sound speed and equation of state and discuss the effect of its clustering on the cold dark matter distribution at the non-linear level. We write the continuity, Euler and Poisson equations for the system in the Newtonian approximation. Then, using the time renormalization group method to resum perturbative corrections at all orders, we compute the total clustering power spectrum and matter power spectrum. At the linear level, a sound speed of dark energy different from that of light modifies the power spectrum on observationally interesting scales, such as those relevant for baryonic acoustic oscillations. We show that the effect of varying the sound speed of dark energy on the non-linear corrections to the matter power spectrum is below the per cent level, and therefore these corrections can be well modelled by their counterpart in cosmological scenarios with smooth dark energy. We also show that the non-linear effects on the matter growth index can be as large as 10-15 per cent for small scales.
description: 33 pages, 7 figures. Improved presentation. References added. Matches published version in JCAP
The region with trapped surfaces in spherical symmetry, its core, and their boundaries
Creators: name: Bengtsson, Ingemar
name: Senovilla, José M. M.
Publisher: name: arXiv
Year: 2010
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We consider the region $\mathscr{T}$ in spacetime containing future-trapped closed surfaces and its boundary $\B$, and derive some of their general properties. We then concentrate on the case of spherical symmetry, but the methods we use are general and applicable to other situations. We argue that closed trapped surfaces have a non-local property, "clairvoyance", which is inherited by $\B$. We prove that $\B$ is not a marginally trapped tube in general, and that it can have portions in regions whose whole past is flat. For asymptotically flat black holes, we identify a general past barrier, well inside the event horizon, to the location of $\B$ under physically reasonable conditions. We also define the core $\mathscr{Z}$ of the trapped region as that part of $\mathscr{T}$ which is indispensable to sustain closed trapped surfaces. We prove that the unique spherically symmetric dynamical horizon is the boundary of such a core, and we argue that this may serve to single it out. To illustrate the results, some explicit examples are discussed, namely Robertson-Walker geometries and the imploding Vaidya spacetime.
description: 70 pages, 14 figures. Figure 6 has been replaced, and corrected. Minor changes around Propositions 10.3 and 10.4, and some typos corrected
Observing the End of Cold Flow Accretion using Halo Absorption Systems
Creators: name: Stewart, Kyle R.
name: Kaufmann, Tobias
name: Bullock, James S.
name: Barton, Elizabeth J.
name: Maller, Ariyeh H.
name: Diemand, Jürg
name: Wadsley, James
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We use cosmological SPH simulations to study the cool, accreted gas in two Milky Way-size galaxies through cosmic time to z=0. We find that gas from mergers and cold flow accretion results in significant amounts of cool gas in galaxy halos. This cool circum-galactic component drops precipitously once the galaxies cross the critical mass to form stable shocks, Mvir = Msh ~ 10^12 Msun. Before reaching Msh, the galaxies experience cold mode accretion (T<10^5 K) and show moderately high covering fractions in accreted gas: f_c ~ 30-50% for R<50 co-moving kpc and N_HI>10^16 cm^-2. These values are considerably lower than observed covering fractions, suggesting that outflowing gas (not included here) is important in simulating galaxies with realistic gaseous halos. Within ~500 Myr of crossing the Msh threshold, each galaxy transitions to hot mode gas accretion, and f_c drops to ~5%. The sharp transition in covering fraction is primarily a function of halo mass, not redshift. This signature should be detectable in absorption system studies that target galaxies of varying host mass, and may provide a direct observational tracer of the transition from cold flow accretion to hot mode accretion in galaxies.
description: 6 pages, 2 figures. Minor changes to match published version (results unchanged)
Qubit thermometry for micromechanical resonators
Creators: name: Brunelli, Matteo
name: Olivares, Stefano
name: Paris, Matteo G. A.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Physics (quant-ph)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We address estimation of temperature for a micromechanical oscillator lying arbitrarily close to its quantum ground state. Motivated by recent experiments, we assume that the oscillator is coupled to a probe qubit via Jaynes-Cummings interaction and that the estimation of its effective temperature is achieved via quantum limited measurements on the qubit. We first consider the ideal unitary evolution in a noiseless environment and then take into account the noise due to non dissipative decoherence. We exploit local quantum estimation theory to assess and optimize the precision of estimation procedures based on the measurement of qubit population, and to compare their performances with the ultimate limit posed by quantum mechanics. In particular, we evaluate the Fisher information (FI) for population measurement, maximize its value over the possible qubit preparations and interaction times, and compare its behavior with that of the quantum Fisher information (QFI). We found that the FI for population measurement is equal to the QFI, i.e., population measurement is optimal, for a suitable initial preparation of the qubit and a predictable interaction time. The same configuration also corresponds to the maximum of the QFI itself. Our results indicate that the achievement of the ultimate bound to precision allowed by quantum mechanics is in the capabilities of the current technology.
description: 9 pages, 5 figures, revised version, to appear on PRA
Necessity of Acceleration-Induced Nonlocality
Creators: name: Mashhoon, Bahram
Publisher: name: arXiv
Year: 2010
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The purpose of this paper is to explain clearly why nonlocality must be an essential part of the theory of relativity. In the standard local version of this theory, Lorentz invariance is extended to accelerated observers by assuming that they are pointwise inertial. This locality postulate is exact when dealing with phenomena involving classical point particles and rays of radiation, but breaks down for electromagnetic fields, as field properties in general cannot be measured instantaneously. The problem is corrected in nonlocal relativity by supplementing the locality postulate with a certain average over the past world line of the observer.
description: 12 pages; v2: improved version accepted for publication in Ann. Phys. (Berlin)
Calculating a confidence interval on the sum of binned leakage
Creators: name: Ruchlin, Ian
name: Schnee, Richard W.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: Calculating the expected number of misclassified outcomes is a standard problem of particular interest for rare-event searches. The Clopper-Pearson method allows calculation of classical confidence intervals on the amount of misclassification if data are all drawn from the same binomial probability distribution. However, data is often better described by breaking it up into several bins, each represented by a different binomial distribution. We describe and provide an algorithm for calculating a classical confidence interval on the expected total number of misclassified events from several bins, based on calibration data with the same probability of misclassification on a bin-by-bin basis. Our method avoids a computationally intensive multidimensional search by introducing a Lagrange multiplier and performing standard root finding. This method has only quadratic time complexity as the number of bins, and produces confidence intervals that are only slightly conservative.
description: 12 pages, 4 figures, to be published in NIMA
The Standard Conjectures for holomorphic symplectic varieties deformation equivalent to Hilbert schemes of K3 surfaces
Creators: name: Charles, François
name: Markman, Eyal
Publisher: name: arXiv
Year: 2010
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: We prove the standard conjectures for complex projective varieties that are deformations of the Hilbert scheme of points on a K3 surface. The proof involves Verbitsky's theory of hyperholomorphic sheaves and a study of the cohomology algebra of Hilbert schemes of K3 surfaces.
description: 15 pages, minor changes