cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Waveform Design via Convex Optimization
Creators: name: De Nicola, Silvio
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2009

description: In this thesis, we propose some original examples of radar waveform design via convex optimization theory. After an initial section introducing some basic concepts about waveform design (chapter 2), we analyze in detail code design for a stand-alone radar in case of temporal (chapter 3) or spatial-temporal processing (chapter 4), and for a networked radar with constraints on the induced interference (chapter 5). Finally, some concluding remarks are presented (chapter 6).
Stellar Evolution in NGC 6791: Mass Loss on the Red Giant Branch and the Formation of Low Mass White Dwarfs
Creators: name: Kalirai, Jasonjot S.
name: Bergeron, P.
name: Hansen, Brad M. S.
name: Kelson, Daniel D.
name: Reitzel, David B.
name: Rich, R. Michael
name: Richer, Harvey B.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present the first detailed study of the properties (temperatures, gravities, and masses) of the NGC 6791 white dwarf population. This unique stellar system is both one of the oldest (8 Gyr) and most metal-rich ([Fe/H] ~ 0.4) open clusters in our Galaxy, and has a color-magnitude diagram (CMD) that exhibits both a red giant clump and a much hotter extreme horizontal branch. Fitting the Balmer lines of the white dwarfs in the cluster, using Keck/LRIS spectra, suggests that most of these stars are undermassive, = 0.43 +/- 0.06 Msun, and therefore could not have formed from canonical stellar evolution involving the helium flash at the tip of the red giant branch. We show that at least 40% of NGC 6791's evolved stars must have lost enough mass on the red giant branch to avoid the flash, and therefore did not convert helium into carbon-oxygen in their core. Such increased mass loss in the evolution of the progenitors of these stars is consistent with the presence of the extreme horizontal branch in the CMD. This unique stellar evolutionary channel also naturally explains the recent finding of a very young age (2.4 Gyr) for NGC 6791 from white dwarf cooling theory; helium core white dwarfs in this cluster will cool ~3 times slower than carbon-oxygen core stars and therefore the corrected white dwarf cooling age is in fact ~7 Gyr, consistent with the well measured main-sequence turnoff age. These results provide direct empirical evidence that mass loss is much more efficient in high metallicity environments and therefore may be critical in interpreting the ultraviolet upturn in elliptical galaxies.
description: 15 pages, 9 figures, 2 tables. Accepted for publication in Astrophys. J. Very minor changes from first version
Numerical simulation of the non-linear transient response of slender beams
Creators: name: Folz, Bryan
Publisher: name: University of British Columbia
Year: 2010

description: A simple numerical solution strategy for predicting the transient response of slender ductile beams, exhibiting geometric and/or material non-linear behaviour, is presented in this study. In the theoretical development of the problem the governing non-linear equation of motion, in variational form, for the bending and stretching of a Bernoulli-Euler beam is established. The numerical solution procedure is then initiated by employing the assumed displacement version of the Finite Element Method with 1-dimensional 6-DOF beam elements. Elastic-plastic strain-hardening of the beam material is conveniently accounted for by means of the "mechanical sublayer model". Visco-plastic material behaviour is included in the analysis through a simple strain-rate dependent constitutive relationship. The equations of motion for the spatially discretized beam are integrated time-wise by means of the central difference method. A variety of examples are then solved and the results compared with solutions from other sources. In general, the numerical solution strategy yields an efficient and accurate modelling of the non-linear transient response of slender ductile beams.
Compositional Bernoulli numbers
Creators: name: Blandin, Hector
name: Diaz, Rafael
Publisher: name: arXiv
Year: 2007
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: We define and study the combinatorial properties of compositional Bernoulli numbers and polynomials within the framework of rational combinatorics.
description: 16 pages, to appear in Afr. Diaspora J. Math
Analisi comparativa dell’attività dei comitati etici nei principali paesi europei
Creators: name: Paternoster, Mariano
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2006

description: L’Autore dopo aver ripercorso le principali tappe che hanno condotto alle direttive europee di good clinical practice in tema di sperimentazione clinica sui farmaci, presenta un’analisi comparativa delle caratteristiche e dell’attività dei comitati etici di 22 paesi europei.
Average annual total sunspot area in the last 410 years: The most probable values and limits of their uncertainties
Creators: name: Nagovitsyn, Yury A.
name: Osipova, Aleksandra A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The aim of this work is to create a long (410 years) series of average annual total sunspot areas AR - physically-based index of sunspot activity. We used telescopic observations of the AR index in 1832-1868 and 1875-2020, as well as the relationship between AR and long series of sunspot indices SN (ISN version 2.0) and sunspot groups GN (Svalgaard and Schatten (2016) GSN version). The Royal Greenwich observatory series after 1976 is extended by the Kislovodsk Mountain Astronomical Station data. When reconstructing AR from SN, it is taken into account that the function AR = f (SN) has a nonlinear systematic character and uncertainty associated with the heterogeneity of these indices. Therefore, in addition to modeling the most probable AR values, predictive limits of reconstruction uncertainty are determined. In the interval 1610-1699 the reconstruction we carried out on the basis of the GN series using the previously proposed decomposition in pseudo-phase space method (DPS). The resulting series NO21y is freely available online. We show that for this series the empirical Gnevyshev-Ohl rule and Waldmeier effect are fulfilled. Wavelet analysis reveals periodicities of 8.4-13.8 years for the main cycle (with a sharp decrease of the period before the global Maunder and Dalton minima) and a two-component Gleissberg cycle with typical periods of 50-60 years and 90-110 years.
Studio prospettico randomizzato mediante l'uso di tre differenti sistemi di emostasi per l'esecuzione della SEPS
Creators: name: Jamshidi, Ali Akbar
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2006

description: L’isufficienza delle vene perforanti di gamba rappresenta una condizione clinica altamente invalidante il cui trattamento chirurgico tradizionale è associata a lunghi tempi di guarigione. La SEPS (Subfascial Endoscopic Perforator Vein Sectioning) è una tecnica videoassistita miniinvasiva efficace e associtata rapida cicatrizzazione delle ulcere da insufficienza delle vene perforanti. Gli autori riportano i risultati di uno studio prospettico comparativo di tre diversi sistemi per l’emostasi delle vene perforanti in termini di efficacia,effetti collaterali e rapporto costo/beneficio.
Rural America at a Glance: 2021 Edition
Creators: name: Dobis, Elizabeth A.
name: Krumel, Thomas P.
name: Cromartie, John
name: Conley, Kelsey L.
name: Sanders, Austin
name: Ortiz, Ruben
name: Dobis, Elizabeth A.
name: Krumel, Thomas P.
name: Cromartie, John
name: Conley, Kelsey L.
name: Sanders, Austin
name: Ortiz, Ruben
Publisher: name: Unknown
Year: 2021
Subjects: Community/Rural/Urban Development
Public Economics
Research Methods/ Statistical Methods

description: The 2021 edition of Rural America at a Glance focuses on aspects affecting the resiliency and recovery of rural communities in the wake of the COVID-19 pandemic, including population and employment change, intensity of infection and vaccination rates, and internet availability and adoption.
Five Degree-of-Freedom Property Interpolation of Arbitrary Grain Boundaries via Voronoi Fundamental Zone Octonion Framework
Creators: name: Baird, Sterling G.
name: Homer, Eric R.
name: Fullwood, David T.
name: Johnson, Oliver K.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Computational Geometry (cs.CG)
subject: Machine Learning (cs.LG)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: We introduce the Voronoi fundamental zone octonion interpolation framework for grain boundary (GB) structure-property models and surrogates. The VFZO framework offers an advantage over other five degree-of-freedom based property interpolation methods because it is constructed as a point set in a manifold. This means that directly computed Euclidean distances approximate the original octonion distance with significantly reduced computation runtime (~7 CPU minutes vs. 153 CPU days for a 50000x50000 pairwise-distance matrix). This increased efficiency facilitates lower interpolation error through the use of significantly more input data. We demonstrate grain boundary energy interpolation results for a non-smooth validation function and simulated bi-crystal datasets for Fe and Ni using four interpolation methods: barycentric interpolation, Gaussian process regression (GPR), inverse-distance weighting, and nearest-neighbor interpolation. These are evaluated for 50000 random input GBs and 10 000 random prediction GBs. The best performance was achieved with GPR, which resulted in a reduction of the root mean square error (RMSE) by 83.0% relative to RMSE of a constant, average model. Likewise, interpolation on a large, noisy, molecular statics Fe simulation dataset improves performance by 34.4% compared to 21.2% in prior work. Interpolation on a small, low-noise MS Ni simulation dataset is similar to interpolation results for the original octonion metric (57.6% vs. 56.4%). A vectorized, parallelized, MATLAB interpolation function (interp5DOF.m) and related routines are available in our VFZO repository (github.com/sgbaird-5dof/interp) which can be applied to other crystallographic point groups. The VFZO framework offers advantages for computing distances between GBs, estimating property values for arbitrary GBs, and modeling surrogates of computationally expensive 5DOF functions and simulations.
description: main: 22 pages, 10 figures; appendices: 5 pages, 3 figures; supp: 13 pages, 12 figures
X-ray Timing of PSR J1852+0040 in Kesteven 79: Evidence of Neutron Stars Weakly Magnetized at Birth
Creators: name: Halpern, J. P.
name: Gotthelf, E. V.
name: Camilo, F.
name: Seward, F. D.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The 105-ms X-ray pulsar J1852+0040 is the central compact object (CCO) in SNR Kes 79. We report a sensitive upper limit on its radio flux density of 12 uJy at 2 GHz using the NRAO GBT. Timing using XMM and Chandra over a 2.4 yr span reveals no significant change in its spin period. The 2 sigma upper limit on the period derivative leads, in the dipole spin-down formalism, to an energy loss rate E-dot < 7e33 ergs/s, surface magnetic field strength B_p < 1.5e11 G, and characteristic age tau_c = P/2P-dot > 8 Myr. This tau_c exceeds the age of the SNR by 3 orders of magnitude, implying that the pulsar was born spinning at its current period. However, the X-ray luminosity of PSR J1852+0040, L(bol) ~ 3e33(d/7.1 kpc)^2 ergs/s is a large fraction of E-dot, which challenges the rotation-powered assumption. Instead, its high blackbody temperature, 0.46+/-0.04 keV, small blackbody radius ~ 0.8 km, and large pulsed fraction, ~ 80%, may be evidence of accretion onto a polar cap, possibly from a fallback disk made of supernova debris. If B_p < 1e10 G, an accretion disk can penetrate the light cylinder and interact with the magnetosphere while resulting torques on the neutron star remain within the observed limits. A weak B-field is also inferred in another CCO, the 424-ms pulsar 1E 1207.4-5209, from its steady spin and soft X-ray absorption lines. We propose this origin of radio-quiet CCOs: the B-field, derived from a turbulent dynamo, is weaker if the NS is formed spinning slowly, which enables it to accrete SN debris. Accretion excludes neutron stars born with both B_p < 1e11 G and P > 0.1 s from radio pulsar surveys, where B_p < 1e11 G is not encountered except among very old (tau_c > 40 Myr) or recycled pulsars. Finally, such a CCO, if born in SN 1987A, could explain the non-detection of a pulsar there.
description: 8 pages, 3 figures, to appear in The Astrophysical Journal
All-optical formation of a Bose-Einstein condensate for applications in scanning electron microscopy
Creators: name: Gericke, T.
name: Wuertz, P.
name: Reitz, D.
name: Utfeld, C.
name: Ott, H.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We report on the production of a F=1 spinor condensate of 87Rb atoms in a single beam optical dipole trap formed by a focused CO2 laser. The condensate is produced 13mm below the tip of a scanning electron microscope employing standard all-optical techniques. The condensate fraction contains up to 100,000 atoms and we achieve a duty cycle of less than 10s.
description: 5 pages, 4 figures
On the Two Species Asymmetric Exclusion Process with Semi-Permeable Boundaries
Creators: name: Ayyer, Arvind
name: Lebowitz, Joel L.
name: Speer, Eugene R.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We investigate the structure of the nonequilibrium stationary state (NESS) of a system of first and second class particles, as well as vacancies (holes), on L sites of a one-dimensional lattice in contact with first class particle reservoirs at the boundary sites; these particles can enter at site 1, when it is vacant, with rate alpha, and exit from site L with rate beta. Second class particles can neither enter nor leave the system, so the boundaries are semi-permeable. The internal dynamics are described by the usual totally asymmetric exclusion process (TASEP) with second class particles. An exact solution of the NESS was found by Arita. Here we describe two consequences of the fact that the flux of second class particles is zero. First, there exist (pinned and unpinned) fat shocks which determine the general structure of the phase diagram and of the local measures; the latter describe the microscopic structure of the system at different macroscopic points (in the limit L going to infinity in terms of superpositions of extremal measures of the infinite system. Second, the distribution of second class particles is given by an equilibrium ensemble in fixed volume, or equivalently but more simply by a pressure ensemble, in which the pair potential between neighboring particles grows logarithmically with distance. We also point out an unexpected feature in the microscopic structure of the NESS for finite L: if there are n second class particles in the system then the distribution of first class particles (respectively holes) on the first (respectively last) n sites is exchangeable.
description: 28 pages, 4 figures. Changed title and introduction for clarity, added references
Probing the circumnuclear environment of NGC1275 with High-Resolution X-ray spectroscopy
Creators: name: Reynolds, Christopher S.
name: Smith, Robyn N.
name: Fabian, Andrew C.
name: Fukazawa, Yasushi
name: Kara, Erin A.
name: Mushotzky, Richard F.
name: Noda, Hirofumi
name: Tombesi, Francesco
name: Veilleux, Sylvain
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: NGC1275 is the Brightest Cluster Galaxy (BCG) in the Perseus cluster and hosts the active galactic nucleus (AGN) that is heating the central 100\,kpc of the intracluster medium (ICM) atmosphere via a regulated feedback loop. Here we use a deep 490ks Cycle-19 Chandra High-Energy Transmission Grating (HETG) observation of NGC1275 to study the anatomy of this AGN. The X-ray continuum is adequately described by an unabsorbed power-law with photon index $Γ\approx 1.9$, creating strong tension with the detected column of molecular gas seen via HCN and HCO$^+$ line absorption against the parsec-scale core/jet. This tension is resolved if we permit a composite X-ray source; allowing a column of $N_H\sim 8\times 10^{22}\,{\rm cm}^{-2}$ to cover $\sim 15$% of the X-ray emitter does produce a significant improvement in the statistical quality of the spectral fit. We suggest that the dominant unabsorbed component corresponds to the accretion disk corona, and the sub-dominant X-ray component is the jet working surface and/or jet cocoon that is expanding into clumpy molecular gas. We suggest that this may be a common occurence in BCG-AGN. We conduct a search for photoionized absorbers/winds and fail to detect such a component, ruling out columns and ionization parameters often seen in many other Seyfert galaxies. We detect the 6.4keV iron-K$α$ fluorescence line seen previously by XMM-Newton and Hitomi. We describe an analysis methodology which combines dispersive HETG spectra, non-dispersive microcalorimeter spectra, and sensitive XMM-Newton/EPIC spectra in order to constrain (sub)arcsec-scale extensions of the iron-K$α$ emission region.
description: 13 pages, accepted for publication in MNRAS
Mapeamento e análise de memes feministas na internet brasileira
Creators: name: Chagas, Viktor
name: Brêtas, Ana Beatriz
Publisher: name: figshare
Year: 2021
Subjects: subject: 200104 Media Studies
subject: FOS: Media and communications

description: Artigo publicado na Revista Eco-Pós, 24(2), 2021.
Precision measurements of large scale structure with future type Ia supernova surveys
Creators: name: Hannestad, Steen
name: Haugboelle, Troels
name: Thomsen, Bjarne
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Type Ia supernovae are currently the best known standard candles at cosmological distances. In addition to providing a powerful probe of dark energy they are an ideal source of information about the peculiar velocity field of the local universe. Even with the very small number of supernovae presently available it has been possible to measure the dipole and quadrupole of the local velocity field out to z~0.025. With future continuous all-sky surveys like the LSST project the luminosity distances of tens of thousands of nearby supernovae will be measured accurately. This will allow for a determination of the local velocity structure of the universe as a function of redshift with unprecedented accuracy, provided the redshifts of the host galaxies are known. Using catalogues of mock surveys we estimate that future low redshift supernova surveys will be able to probe sigma-8 to a precision of roughly 5% at 95% C.L. This is comparable to the precision in future galaxy and weak lensing surveys and with a relatively modest observational effort it will provide a crucial cross-check on future measurements of the matter power spectrum.
description: 18 pages, 9 figures, submitted to JCAP
Star product algebras of test functions
Creators: name: Soloviev, Michael A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mathematical Physics (math-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Quantum Algebra (math.QA)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 53D55, 46E25, 46F05 (Primary) 81T05, 46L65 (Secondary)

description: We prove that the Gelfand-Shilov spaces $S^β_α$ are topological algebras under the Moyal star product if and only if $α\geβ$. These spaces of test functions can be used in quantum field theory on noncommutative spacetime. The star product depends on the noncommutativity parameter continuously in their topology. We also prove that the series expansion of the Moyal product converges absolutely in $S^β_α$ if and only if $β<1/2$.
description: AMS-LaTeX, 12 pages, no figures; typos corrected, minor changes to agree with published version
Pharmacology and Toxiclogy of Echinacea, Souroubea and Platanus spp.
Creators: name: Liu, Rui
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2019
Subjects: Natural health products
Endocannabinoid system
Phytochemistry
Herb-Drug interaction

description: The research presented in this thesis addressed knowledge gaps for three medicinal plant taxa, Souroubea spp. (Marcgraviaceae) and Platanus (Platanaceae) as well as Echinacea spp. (Asteraceae). The primary pharmacological mechanism of Souroubea sympetala and Platanus occidentalis were well established, with pentacyclic triterpenes identified as major active principles. My results indicate that major triterpenoids, and crude plant extracts, selectively inhibited monoacyglycerol lipase (MAGL) activity but not fatty acid amide hydrolase (FAAH) activity. These data suggest a possible secondary anxiolytic mechanism of action through the endocannabinoid system (ECS). My study of herb-drug interactions of Souroubea and Plantanus products showed some potential risk when combined with a classic benzodiazepine class drug, diazepam, and I proposed a mechanism through in vitro CYP450 enzyme inhibition. The pharmacokinetic study revealed the difficulty of detecting betulinic acid in animal blood. To support the development a commercial botanical composed of these medicinal plants, an extraction method and a highly sensitive and selectivity HPLC-APCI-MS based quantification method was successfully developed and validated. Part II of this thesis focused on the impact of phytochemical variation and hepatic metabolism on the ECS activity of Echinacea spp. and explored the potential for new applications of Echinacea spp. as a natural health product. My research indicated that considerable variability in the content of phenolic and alkylamide (AKA) compounds reflected similar variability in in vitro bioactivity at ECS-related pharmacological targets. Following biochemometric analysis, several phenolic compounds and AKAs in Echinacea spp. were found to be significant independent variables determining FAAH inhibition and CB receptor activation. Hepatic metabolism was also found to affect the FAAH inhibition of AKA, as increased FAAH inhibitory effects were observed after CYP450-mediated metabolism of both individual AKAs and crude extracts of E angustifolia and E. purpurea, suggesting a “pro-drug” mechanism. Dose dependent activities were observed with oral administration of both E angustifolia and E. purpurea root extract in rat paw model of inflammation and pain. Further tests indicated these activities can be partially blocked by co-administration of CB1 and CB2 receptor antagonists AM251 and AM630, respectively. This evidence suggests activity for peripheral pain was at least partially mediated through the ECS.
Positive mass theorem for the Paneitz-Branson operator
Creators: name: Humbert, Emmanuel
name: Raulot, Simon
Publisher: name: arXiv
Year: 2008
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: We prove that under suitable assumptions, the constant term in the Green function of the Paneitz-Branson operator on a compact Riemannian manifold $(M,g)$ is positive unless $(M,g)$ is conformally diffeomophic to the standard sphere. The proof is inspired by the positive mass theorem on spin manifolds by Ammann-Humbert.
description: 7 pages
End-User Security & Privacy Behaviour on Social Media: Exploring Posture, Proficiency & Practice
Creators: name: Akbari Koochaksaraee, Amir
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2019
Subjects: Cybersecurity
Social Media
End-users

description: Security and privacy practices of end-users on social media are an important area of research, as well as a top-of-mind concern for individuals as well as organizations. In recent years, we have seen a sharp increase in data breaches and cyber security threats that have targeted social media users. Hence, it is imperative that we try to better understand factors that affect an end-user’s adoption of effective security safeguards and privacy protection practices. In this research, we propose and validate a theoretical model that posits several determinants of end-user security and privacy practices on social media. We hypothesize relationships among various cognitive, affective and behavioral factors identified under the themes of posture, proficiency, and practices. These constructs and hypotheses are validated through empirical research comprising an online survey questionnaire, and structural equation modeling (SEM) analysis. The key findings of this study highlight the importance of cyber threat awareness and social media security and privacy self-efficacy, which have a direct impact on end-user security and privacy practices. Additionally, our research shows that use of general technology applications for security and privacy impacts the adoption of security and privacy practices on social media. In totality, our research findings indicate that proficiency is a better predictor or security and privacy practices as compared to the posture of an end-user. Factors such as privacy disposition, privacy concerns, and perceived risk of privacy violations do not have as significant or direct effect on security and privacy practices. Based on our research findings, we provide some key take-aways in the form of theoretical contributions, suggestions for future research, as well as recommendations for organizational security awareness training programs.
Strong magnetic spiral pattern in a ringed galaxy NGC4736
Creators: name: Chyzy, Krzysztof T.
name: Buta, Ronald J.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present high sensitivity radio polarimetric (VLA) observations of a galaxy with strong orbital resonances - NGC4736. The total radio intensity at 8.4GHz covers smoothly the whole galaxy bulge and reveals a distinct ring of radio emission closely related to the ring morphology visible in infrared, CO and Halpha emission. However, the magnetic field reveals a very coherent spiral pattern. The magnetic field vectors are crossing the inner starbursting ring, the dust lanes within the ring and other rather circularly shaped features visible in other gas traces. Either the magnetic field uncovers the pattern of gas motions not seen in other spectral ranges, or the spiral magnetic field is of a pure dynamo origin, ignoring the ringed morphology of the galaxy.
description: 2 pages, 1 figure, To appear in the proceedings of IAU Symposium 245, "Formation and Evolution of Galaxy Bulges," M. Bureau, E. Athanassoula, and B. Barbuy, eds
Charting the landscape of supercritical string theory
Creators: name: Hellerman, Simeon
name: Swanson, Ian
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Special solutions of string theory in supercritical dimensions can interpolate in time between theories with different numbers of spacetime dimensions (via dimension quenching) and different amounts of worldsheet supersymmetry (via c-duality). These solutions connect supercritical string theories to the more familiar string duality web in ten dimensions, and provide a precise link between supersymmetric and purely bosonic string theories. Dimension quenching and c-duality appear to be natural concepts in string theory, giving rise to large networks of interconnected theories. We describe some of these networks in detail and discuss general consistency constraints on the types of transitions that arise in this framework.
description: 27 pages, 4 figures
Disorder-induced tail states in a gapped bilayer graphene
Creators: name: Mkhitaryan, V. V.
name: Raikh, M. E.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The instanton approach to the in-gap fluctuation states is applied to the spectrum of biased bilayer graphene. It is shown that the density of states falls off with energy measured from the band-edge as $ν(ε)\propto \exp(-|ε/ε_t|^{3/2})$, where the characteristic tail energy, $ε_t$, scales with the concentration of impurities, $n_i$, as $n_i^{2/3}$. While the bare energy spectrum is characterized by two energies: the bias-induced gap, $V$, and interlayer tunneling, $t_{\perp}$, the tail, $ε_t$, contains a {\it single} combination $V^{1/3}t_{\perp}^{2/3}$. We show that the above expression for $ν(ε)$ in the tail actually applies all the way down to the mid-gap.
description: 7 pages, 4 figures
Mecodema oregoides
Creators: name: Larochelle
name: Larivière, Marie-Claude
name: Larochelle
name: Larivière
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Carabidae
Mecodema
Mecodema oregoides

description: Mecodema oregoides (Broun, 1894) – Endemic [p. 59]
  Mecodema parataiko Seldon and Leschen, 2011  – Endemic
 Mecodema parataiko Seldon and Leschen, 2011: 34. Type locality: Mangamuka Gorge Walkway, ND.
description: Published as part of Larochelle, Larivière, Marie-Claude, Larochelle & Larivière, 2016, Taxonomic Supplement (2001 to 2015) to the Catalogue of New Zealand Carabidae (Insecta: Coleoptera), pp. 1-53 in Insecta Mundi 2016 (502) on page 11, DOI: 10.5281/zenodo.5170780
Flipped on its Head: deep learning-based saliency finds asymmetry in the opposite direction expected for singleton search of flipped and canonical targets
Creators: name: Calden Wloka
name: Tsotsos, John K.
Publisher: name: F1000 Research Limited
Year: 2019

description: A search asymmetry occurs when it is faster for an observer to find some search target A amongst a set of distractors B than when searching for a target B amongst a set of A distractors. A number of search asymmetries are well-established in humans, but the phenomenon is less well studied by research into computational saliency models. Nevertheless, if these algorithsm are truly representing a component of early human visual attention, they should also be able to account for aspects of human attention beyond simply testing prediction performance on free-viewing fixation datasets (Bruce et al., 2015). Leveraging the recently developed Saliency Model Implementation Library for Experimental Research (SMILER), we devise a set of visual search arrays and test whether learned models of saliency exhibit an asymmetry of performance for targets with a novel flipped orientation over canonically oriented targets. Our findings show that the deep learning approach to computational saliency modelling which currently dominates the field consistently displays an asymmetric preference for canonically oriented stimuli. This asymmetry in performance runs counter to the behavioural performance patterns expected of human subjects, and suggests that the pattern-matching nature of deep learning is insufficient to fully account for human judgements of target salience.
Quark-Gluon Plasmas and Thermalization
Creators: name: Arnold, Peter
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: In these lectures, I will attempt a pedagogical and qualitative introduction to the theory of equilibrium and thermalization of quark-gluon plasmas. I assume only that the reader is familiar with quantum field theory at zero temperature and with QCD as the theory of the strong interactions. I focus on the limit of small alpha_s, which in principle should be relevant at extremely high temperature because of asymptotic freedom, and in any case provides a clean theoretical context in which to discuss a variety of phenomena. Topics discussed include the basic equilibrium formalism for finite-temperature quantum field theory, Debye screening, electric deconfinement, magnetic confinement, dimensional reduction, plasma waves, kinetic theory, hydrodynamic properties such as viscosity, the Landau-Pomeranchuk-Migdal effect, thermalization in (arbitrarily high energy) heavy ion collisions, and QCD plasma instabilities.
description: 40 pages; based on lectures given at X Hadron Physics in Florianopolis, SC, Brazil, March 26-31, 2007 [another small typo fixed]
Galaxy Core Formation by Supermassive Black Hole Binaries: the Importance of Realistic Initial Conditions and Galaxy Morphology
Creators: name: Dosopoulou, Fani
name: Greene, Jenny E.
name: Ma, Chung-Pei
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The binding energy liberated by the coalescence of supermassive black hole (SMBH) binaries during galaxy mergers is thought to be responsible for the low density cores often found in bright elliptical galaxies. We use high-resolution $N$-body and Monte Carlo techniques to perform single and multi-stage galaxy merger simulations and systematically study the dependence of the central galaxy properties on the binary mass ratio, the slope of the initial density cusps, and the number of mergers experienced. We study both the amount of depleted stellar mass (or ``mass deficit'), $M_{\rm def}$, and the radial extent of the depleted region, $r_{\rm b}$. We find that $r_{\rm b}\simeq r_{\rm SOI}$ and that $M_{\rm def}$ varies in the range $0.5$ to $4M_{\bullet}$, with $r_{\rm SOI}$ the influence radius of the remnant SMBH and $M_{\bullet}$ its mass. The coefficients in these relations depend weakly on the binary mass ratio and remain remarkably constant through subsequent mergers. We conclude that the core size and mass deficit do not scale linearly with the number of mergers, making it hard to infer merger histories from observations. On the other hand, we show that both $M_{\rm def}$ and $r_{\rm b}$ are sensitive to the morphology of the galaxy merger remnant, and that adopting spherical initial conditions, as done in early work, leads to misleading results. Our models reproduce the range of values for $M_{\rm def}$ found in most observational work, but span nearly an order of magnitude range around the true ejected stellar mass.
description: 19 pages, 9 figures, 4 tables. Accepted for publication to ApJ, comments are welcome
Effects of phosphorus addition on treatment efficiency of an anaerobic filter treating landfill leachate
Creators: name: Muthukrishnan, Karthikeyan
Publisher: name: University of British Columbia
Year: 2010

description: Sanitary landfill leachate is a source of environmental concern due to its high organic strength and chemical diversity. The widespread use of sanitary landfills has resulted in regulatory authorities requiring municipalities to give serious consideration to the treatment and safe disposal of this wastewater. A number of lab-scale and pilot scale studies have indicated that the anaerobic filter .is highly competitive with other forms of biological treatment and has distinct economic advantages. While there have been a number of studies based on a general overall approach to leachate treatment by the anaerobic filter, limited' information is available on the role played by essential nutrients (phosphorus and nitrogen) in the biological treatment process. Laboratory studies were conducted at room temperature (22°C) to study the effect of nutrient addition (specifically, phosphorus, the deficient constituent of most leachates) on treatment efficiency of landfill leachate by the upflow anaerobic filter. Two anaerobic filters (0.975 metres x 0.15 metres diameter) were constructed using plexiglass pipes and packed with strips of corrugated fibre-glass sheets in four layers to form the filter bed. Leachate collected from a nearby landfill was applied at moderate organic loadings (2.0-4.2 kg COD/m³.day) to the two units maintaining a HRT of 0.987 days. During runs 2 and 4, leachate collected from the Premier landfill had a very low organic strength, necessitating the addition of acetic acid to raise that strength to around 2000 mg/l COD. When phosphorus addition was made at the 10 mg/l level to this feed, no favourable effect on COD removal was observed, possibly because the feed was VFA based and not inclusive of complex organics. During run 3, the strength of the leachate increased to around 4000 mg/l, with a relatively lower proportion of the COD present as VFA (around 1600 mg/l as acetic acid). When phosphorus addition was made to this feed at a 40 mg/l level, COD removal capacity of the anaerobic filter improved significantly, indicating that phosphorus may be added to an organically diverse waste with distinct advantages.
The Brera Multi-scale Wavelet Chandra Survey. I. Serendipitous source catalogue
Creators: name: Romano, P.
name: Campana, S.
name: Mignani, R. P.
name: Moretti, A.
name: Mottini, M.
name: Panzera, M. R.
name: Tagliaferri, G.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present the BMW-Chandra source catalogue drawn from essentially all Chandra ACIS-I pointed observations with an exposure time in excess of 10ks public as of March 2003 (136 observations). Using the wavelet detection algorithm developed by Lazzati et al. (1999) and Campana et al. (1999), which can characterise both point-like and extended sources, we identified 21325 sources. Among them, 16758 are serendipitous, i.e. not associated with the targets of the pointings, and do not require a non-automated analysis. This makes our catalogue the largest compilation of Chandra sources to date. The 0.5--10 keV absorption corrected fluxes of these sources range from ~3E-16 to 9E-12 erg cm^-2 s^-1 with a median of 7E-15 erg cm^-2 s^-1. The catalogue consists of count rates and relative errors in three energy bands (total, 0.5-7keV; soft, 0.5-2keV; and hard, 2-7keV), and source positions relative to the highest signal-to-noise detection among the three bands. The wavelet algorithm also provides an estimate of the extension of the source. We include information drawn from the headers of the original files, as well, and extracted source counts in four additional energy bands, SB1 (0.5-1keV), SB2 (1-2keV), HB1 (2-4keV), and HB2 (4-7keV). We computed the sky coverage for the full catalogue and for a subset at high Galactic latitude (|b|> 20deg). The complete catalogue provides a sky coverage in the soft band (0.5-2keV, S/N =3) of ~8 deg^2 at a limiting flux of 1E-13 erg cm^-2 s^-1, and ~2 deg^2 at a limiting flux of ~1E-15 erg cm^-2 s^-1.
description: Accepted by A&A, Higher res. Figs 4 and 5 at http://www.ifc.inaf.it/~romano/BMC/Docs/aapaper/9601f4.eps http://www.ifc.inaf.it/~romano/BMC/Docs/aapaper/9601f5.eps, Catalog Web pages: http://www.brera.inaf.it/BMC/bmc_home.html http://www.ifc.inaf.it/~romano/BMC/bmc_home.html (Mirror)
Mecodema pavidum Townsend 1965
Creators: name: Larochelle
name: Larivière, Marie-Claude
name: Larochelle
name: Larivière
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Carabidae
Mecodema
Mecodema pavidum

description: Mecodema pavidum Townsend, 1965 – Endemic [p. 48]
  Mecodema persculptum Broun, 1915  – Endemic [p. 49, under Mecodema rugiceps rugiceps] Mecodema persculptum Broun, 1915: 271. Type locality: Lake Mackenzie, OL. Synonymized with Mecodema rugiceps rugiceps by Townsend (1965: 311); resurrected from synonymy by Johns (2005: 63).
description: Published as part of Larochelle, Larivière, Marie-Claude, Larochelle & Larivière, 2016, Taxonomic Supplement (2001 to 2015) to the Catalogue of New Zealand Carabidae (Insecta: Coleoptera), pp. 1-53 in Insecta Mundi 2016 (502) on page 11, DOI: 10.5281/zenodo.5170780
Can We Detect the Anisotropic Shapes of Quasar HII Regions During Reionization Through The Small-Scale Redshifted 21cm Power Spectrum?
Creators: name: Sethi, Shiv
name: Haiman, Zoltán
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Light travel time delays distort the apparent shapes of HII regions surrounding bright quasars during early stages of cosmic reionization. Individual HII regions may remain undetectable in forthcoming redshifted 21 cm experiments. However, the systematic deformation along the line of sight may be detectable statistically, either by stacking tomographic 21cm images of quasars identified, for example, by JWST, or as small-scale anisotropy in the three-dimensional 21cm power spectrum. Here we consider the detectability of this effect. The anisotropy is largest when HII regions are large and expand rapidly, and we find that if bright quasars contributed to the early stages of reionization, then they can produce significant anisotropy, on scales comparable to the typical sizes of HII regions of the bright quasars (approx. 30 Mpc and below). The effect therefore cannot be ignored when analyzing future 21cm power spectra on small scales. If 10 percent of the volume of the IGM at redshift z=10 is ionized by quasars with typical ionizing luminosity of S= 5 x 10^{56} photons/second, the distortions can enhance by more than 10 percent the 21cm power spectrum in the radial (redshift) direction, relative to the transverse directions. The level of this anisotropy exceeds that due to redshift-space distortion, and has the opposite sign. We show that on-going experiments such as MWA should be able to detect this effect. A detection would reveal the presence of bright quasars, and shed light on the ionizing yield and age of the ionizing sources, and the distribution and small-scale clumping of neutral intergalactic gas in their vicinity.
description: Version accepted by ApJ, with new fiducial model and improved discussion
In what sense (if any) is meaning normative?
Creators: name: Miller, Taylor-Grey
name: 0000-0002-7515-3859
Publisher: name: The University of Texas at Austin
Year: 2018
Subjects: Meaning
Normativity
Kripke
Rule-following
Constitutive
Language
Logic

description: "Meaning is normative" has become a popular dictum in the philosophy of language. Moreover, some proponents of the dictum have appealed to the normativity of meaning in order to demonstrate the hopelessness of a reduction of semantic to non-semantic vocabulary. The upshot, some maintain is that this stands in the way of a naturalistically respectable theory of meaning. The aim of this paper is to get clear on what exactly the dictum should amount to in order to pose a problem for a naturalistic theory of meaning and then see whether the dictum is true. I will argue that the most plausible version of the thesis that meaning is normative poses no real threat to the possibility of naturalism about meaning
Experimental test of nonlocal realistic theories without the rotational symmetry assumption
Creators: name: Paterek, Tomasz
name: Fedrizzi, Alessandro
name: Groeblacher, Simon
name: Jennewein, Thomas
name: Zukowski, Marek
name: Aspelmeyer, Markus
name: Zeilinger, Anton
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We analyze the class of nonlocal realistic theories that was originally considered by Leggett [Found. Phys. 33, 1469 (2003)] and tested by us in a recent experiment [Nature (London) 446, 871 (2007)]. We derive an incompatibility theorem that works for finite numbers of polarizer settings and that does not require the previously assumed rotational symmetry of the two-particle correlation functions. The experimentally measured case involves seven different measurement settings. Using polarization-entangled photon pairs, we exclude this broader class of nonlocal realistic models by experimentally violating a new Leggett-type inequality by 80 standard deviations.
description: Published version
Mecodema politanum Broun 1917
Creators: name: Larochelle
name: Larivière, Marie-Claude
name: Larochelle
name: Larivière
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Carabidae
Mecodema
Mecodema politanum

description: Mecodema politanum Broun, 1917 – Endemic [p. 57]
  Mecodema ponaiti Seldon and Leschen, 2011  – Endemic
 Mecodema ponaiti Seldon and Leschen, 2011: 36. Type locality: Poor Knights Islands, Tawhiti Rahi Island, ND.
description: Published as part of Larochelle, Larivière, Marie-Claude, Larochelle & Larivière, 2016, Taxonomic Supplement (2001 to 2015) to the Catalogue of New Zealand Carabidae (Insecta: Coleoptera), pp. 1-53 in Insecta Mundi 2016 (502) on page 11, DOI: 10.5281/zenodo.5170780
A Dark Energy model from Generalized Proca Theory
Creators: name: Geng, Chao-Qiang
name: Hsu, Yan-Ting
name: Lu, Jhih-Rong
name: Yin, Lu
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We consider a specific dark energy model, which only includes the Lagrangian up to the cubic order in terms of the vector field self-interactions in the generalized Proca theory. We examine the cosmological parameters in the model by using the data sets of CMB and CMB+HST, respectively. In particular, the Hubble constant is found to be $H_0=71.80^{+1.07}_{-0.72}$ ($72.48^{+0.72}_{-0.60}$) $\rm kms^{-1}Mpc^{-1}$ at $68\%$~C.L. with CMB (CMB+HST), which would alleviate the Hubble constant tension. We also obtain that the reduced $χ^2$ values in our model are close to unity when fitting with CMB and CMB+HST, illustrating that our model is a good candidate to describe the cosmological evolutions of the universe.
description: 18 pages, 5 figures, accepted by Physics of the Dark Universe
A Comparative Study of Vulnerability Reporting by Software Composition Analysis Tools
Creators: name: Imtiaz, Nasif
name: Thorne, Seaver
name: Williams, Laurie
Publisher: name: arXiv
Year: 2021
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: Background: Modern software uses many third-party libraries and frameworks as dependencies. Known vulnerabilities in these dependencies are a potential security risk. Software composition analysis (SCA) tools, therefore, are being increasingly adopted by practitioners to keep track of vulnerable dependencies. Aim: The goal of this study is to understand the difference in vulnerability reporting by various SCA tools. Understanding if and how existing SCA tools differ in their analysis may help security practitioners to choose the right tooling and identify future research needs. Method: We present an in-depth case study by comparing the analysis reports of 9 industry-leading SCA tools on a large web application, OpenMRS, composed of Maven (Java) and npm (JavaScript) projects. Results: We find that the tools vary in their vulnerability reporting. The count of reported vulnerable dependencies ranges from 17 to 332 for Maven and from 32 to 239 for npm projects across the studied tools. Similarly, the count of unique known vulnerabilities reported by the tools ranges from 36 to 313 for Maven and from 45 to 234 for npm projects. Our manual analysis of the tools' results suggest that accuracy of the vulnerability database is a key differentiator for SCA tools. Conclusion: We recommend that practitioners should not rely on any single tool at the present, as that can result in missing known vulnerabilities. We point out two research directions in the SCA space: i) establishing frameworks and metrics to identify false positives for dependency vulnerabilities; and ii) building automation technologies for continuous monitoring of vulnerability data from open source package ecosystems.
description: In Proceedings of the 15th International Symposium on Empirical Software Engineering and Measurement