cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Chemistry of a protoplanetary disk with grain settling and Lyman alpha radiation
Creators: name: Fogel, Jeffrey K. J.
name: Bethell, Thomas J.
name: Bergin, Edwin A.
name: Calvet, Nuria
name: Semenov, Dmitry
Publisher: name: arXiv
Year: 2010
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present results from a model of the chemical evolution of protoplanetary disks. In our models we directly calculate the changing propagation and penetration of a high energy radiation field with Lyman alpha radiation included. We also explore the effect on our models of including dust grain settling. We find that, in agreement with earlier studies, the evolution of dust grains plays a large role in determining how deep the UV radiation penetrates into the disk. Significant grain settling at the midplane leads to much smaller freeze-out regions and a correspondingly larger molecular layer, which leads to an increase in column density for molecular species such as CO, CN and SO. The inclusion of Lyman alpha radiation impacts the disk chemistry through specific species that have large photodissociation cross sections at 1216 A. These include HCN, NH3 and CH4, for which the column densities are decreased by an order of magnitude or more due to the presence of Lyman alpha radiation in the UV spectrum. A few species, such as CO2 and SO, are enhanced by the presence of Lyman alpha radiation, but rarely by more than a factor of a few.
description: 17 pages, 15 Figures. Accepted to ApJ
Colourful FKS subtraction
Creators: name: Frixione, Stefano
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: I formulate in a colour-friendly way the FKS method for the computation of QCD cross sections at the next-to-leading order accuracy. This is achieved through the definition of subtraction terms for squared matrix elements, constructed with single colour-dressed or pairs of colour-ordered amplitudes. The latter approach relies on the use of colour flows, is exact to all orders in $N$, and is thus particularly suited to being organized as a systematic expansion in 1/N.
description: 56 pages. This version is identical to that published in JHEP, except for a couple of minor corrections in app. C
Playing the race card : racial bias in judicial decision-making
Creators: name: Luesley, Andrew John Arthur
Publisher: name: University of British Columbia
Year: 2017

description: Racial bias does not have to be explicit to be felt. In the context of the criminal justice system, even implicit bias can have huge impacts on complainants and accused. While judicial impartiality and neutrality are hallowed principles in our judicial system, there is clear evidence of racial bias in judicial decision-making. The prevalence of racial bias throughout the criminal justice system creates the need for explicit considerations of race for the system to produce substantive equality, and for the legal system to apply to and protect all people equally. Sexual assault is an area of law where complainants likely face implicit racial bias. Further, it is possible that there is less perceived societal harm to the sexual assault of minorities. If racial complainants are less likely to be believed, or are less sympathetic complainants, then the criminal justice system will fail to adequately deter crimes against minorities. This thesis asserts that counsel should be advancing the topic of race in the context of sexual assault due to its racialized nature and the pressing need to find a way to reduce its prevalence as the current approach has failed to do over the last ten years or more. If the topic of race is raised, it allows the judge to attempt to counteract any of his potential implicit biases, as well as factor race into his considerations regarding deterrence. The current erasure of race in sentencing impacts both complainants and accused, and may limit the criminal justice systems ability to effectively deter crime. Ultimately, the thesis suggests judges record the race of the accused and complainant in their sentencing decisions for sexual assault. This data on the racial demographics of sexual assault convictions will allow researchers to measure judicial racial bias in sentencing, as to identify whether there is explicit, implicit and/or structure inequality in the criminal justice system such that sexual assaults involving minority complainants are less likely to result in convictions.
Acoustic metafluids made from three acoustic fluids
Creators: name: Norris, Andrew N.
name: Nagy, Adam J.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Significant reduction in target strength and radiation signature can be achieved by surrounding an object with multiple concentric layers comprised of three acoustic fluids. The idea is to make a finely layered shell with the thickness of each layer defined by a unique transformation rule. The shell has the effect of steering incident acoustic energy around the structure, and conversely, reducing the radiation strength. The overall effectiveness and the precise form of the layering depends upon the densities and compressibilities of the three fluids. Nearly optimal results are obtained if one fluid has density equal to the background fluid, while the other two densities are much greater and much less than the background values. Optimal choices for the compressibilities are also found. Simulations in 2D and 3D illustrate effectiveness of the three fluid shell. The limited range of acoustic metafluids that are possible using only two fluid constituents is also discussed.
description: 12 pages, 11 figures
HEJ 2: High Energy Resummation for Hadron Colliders
Creators: name: Andersen, Jeppe R.
name: Hapola, Tuomas
name: Heil, Marian
name: Maier, Andreas Martin
name: Smillie, Jennifer
Publisher: name: Deutsches Elektronen-Synchrotron, DESY, Hamburg
Year: 2019
Subjects: Higgs particle: production
energy: high
jet: energy
vector boson: fusion
Monte Carlo
resummation
background
hadron

description: We present HEJ 2, a new implementation of the High Energy Jets formalism for high-energy resummation in hadron-collider processes as a flexible Monte Carlo event generator. In combination with a conventional fixed-order event generator, HEJ 2 can be used to obtain greatly improved predictions for a number of phenomenologically important processes by adding all-order logarithmic corrections in $\hat{s}/p_\perp^2$. A prime example for such a process is the gluon-fusion production of a Higgs boson in association with widely separated jets, which constitutes the dominant background to Higgs boson production in weak-boson fusion.
Five-Loop Static Contribution to the Gravitational Interaction Potential of Two Point Masses
Creators: name: Blümlein, J.
name: Maier, Andreas Martin
name: Marquard, P.
Publisher: name: Deutsches Elektronen-Synchrotron, DESY, Hamburg
Year: 2019
Subjects: gravitation: interaction
effective action
Feynman graph

description: We compute the static contribution to the gravitational interaction potential of two point masses in the velocity-independent five-loop (and 5th post-Newtonian) approximation to the harmonic coordinates effective action in a direct calculation. The computation is performed using effective field methods based on Feynman diagrams in momentum-space in $d = 3 - 2\varepsilon$ space dimensions. We also reproduce the previous results including the 4th post-Newtonian order.
Essays on politically connected firms
Creators: name: Duo, Yi
Publisher: name: University of British Columbia
Year: 2017

description: This thesis explores a number of issues related to politically connected firms in two separate chapters. I follow Goldman et al. (2009), defining politically connected firms as those with at least one former politician serving as member of its board of directors, and construct a sample containing the S&P 500 firms between 2004 and 2013. The first chapter explores why firms seek these political connections, and how they benefit from two direct value extraction channels: government procurement and subsidies. I find that firms that aim for government contracts seek executive branch connections, while those that face heavy regulations target congressional connections. Next, I show that politically connected firms do get more government contracts and subsidies. Firm performance (using accounting based measures) suffers with government contracts and subsidies, and political connections fail to increase or decrease this negative relation, which suggests effective safeguards against overpricing and cronyism. However, politically connected firms do seem to enjoy a temporary increase in future ROA, when government contracts are taken into consideration. The second chapter asks if politically connected firms pay higher audit fees, and explores the underlying reasons. Prior studies have mixed implications on how risky these clients are for auditors. On the one hand, some studies suggest politically connected firms have lower accounting quality and face higher political risk, hence incur higher audit fees. On the other hand, less investor pressure and lower litigation and bankruptcy risks would decrease audit fees for firms with political connections. I find that politically connected firms do pay higher audit fees, and the effect is stronger for those with executive branch connections. Neither lower accounting quality nor higher political risk is found to be the underlying reason. The fact that many politically connected firms are government contractors, who are subject to additional regulations and government audit, is found to be the main factor for this difference in audit fee.
Identificación de nuevos medicamentos a través de métodos computacionales
Creators: name: Isea, Raul
Publisher: name: arXiv
Year: 2010
Subjects: subject: Other Quantitative Biology (q-bio.OT)
subject: FOS: Biological sciences

description: Resumen: El desarrollo de nuevos medicamentos es un problema complejo que carece de una solución única y automática desde un punto de vista computacional, debido a la carencia de programas que permitan manejar grandes volúmenes de información que están distribuidos a lo largo de todo el mundo entre múltiples bases de datos. Por ello se describe una metodología que permita realizar experimentos in silico para la identificación actual de nuevos medicamentos. Abstract: The development of new drugs is a problem that nowadays has no solution in terms of computational power due to the lack of software for handling the big volume of available information; besides, these data are stored in multiple formats and are distributed all around the world. To resolve that, a development of an in silico drug design methodology.
description: 20 pages, 4 figures, Spanish paper
Transition to the disk dominant state of a new ultraluminous X-ray source in M82
Creators: name: Jin, Jing
name: Feng, Hua
name: Kaaret, Philip
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We report on the identification of a third, new ultraluminous X-ray source (ULX) in the starburst galaxy M82. Previously, the source was observed at fluxes consistent with the high state of Galactic black hole binaries (BHBs). We observe fluxes up to (6.5 +/- 0.3)E39 ergs/s in the ultraluminous regime. When the source is not in the the low/hard state, spectral fitting using a multicolor disk model shows that the disk luminosity varies as the disk inner temperature raised to the power 4.8 +/- 0.9, consistent with the behavior of Galactic BHBs in the thermal dominant state. Fitting the spectrum with a multicolor disk model with general relativistic corrections suggests that the source harbors a rapidly spinning black hole with a mass less than 100 solar masses. A soft excess was found in the source spectrum that could be blackbody emission from a photosphere created by a massive outflow. The source also showed soft dips during a flare.
Neue Aspekte in der Chemie von Übergangsmetallpolysulfidkomplexen: Synthese und Kristallstrukturen von Cp′3Nb3S12 und Cp′3Nb3S10O (Cp′ = t-BuC5H4)
Creators: name: Brunner, Henri
name: Meier, W.
name: Wachter, Joachim
name: Nuber, Bernd
name: Ziegler, M. L.
Publisher: name: Universität Regensburg
Year: 1990
Subjects: subject: 540 Chemie

description: Thermolysis of a mixture of Cp′4Nb2Sn (Cp′ = t-BuC5H4; n = 8, 9) results in the formation of the new niobium polysulfide complexes: Cp′3Nb3S12 (2), Cp′3Nb3S10O (3), Cp′3Nb3S10O (4) and Cp′4Nb4S13 (5). The structures of 2 and 3 have been established by X-ray diffraction studies. The complexes are characterized by an unusual variety of different sulfur ligands (up to five in 2), which is responsible for the absence of any metal-metal interaction.
Fermi Large Area Telescope Observations of Gamma-ray Pulsars PSR J1057-5226, J1709-4429, and J1952+3252
Creators: name: Fermi LAT Collaboration
name: Abdo, A. A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The Fermi Large Area Telescope (LAT) data have confirmed the pulsed emission from all six high-confidence gamma-ray pulsars previously known from the EGRET observations. We report results obtained from the analysis of 13 months of LAT data for three of these pulsars (PSR J1057-5226, PSR J1709-4429, and PSR J1952+3252) each of which had some unique feature among the EGRET pulsars. The excellent sensitivity of LAT allows more detailed analysis of the evolution of the pulse profile with energy and also of the variation of the spectral shape with phase. We measure the cutoff energy of the pulsed emission from these pulsars for the first time and provide a more complete picture of the emission mechanism. The results confirm some, but not all, of the features seen in the EGRET data.
description: Accepted for publication in ApJ. 45 pages, 12 figures, 11 tables. Corresponding authors: O. Celik, F. Gargano, T. Reposeur, D.J. Thompson
Greenberger-Horne-Zeilinger States in Quantum Dot Molecule
Creators: name: Sharma, Anand
name: Hawrylak, Pawel
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present a microscopic theory of a lateral quantum dot molecule in a radial magnetic field with a Greenberger- Horne- Zeilinger (GHZ) maximally entangled three particle groundstate. The quantum dot molecule consists of three quantum dots with one electron spin each forming a central equilateral triangle. The anti-ferromagnetic spin-spin interaction is changed to the ferromagnetic interaction by additional doubly occupied quantum dots, one dot near each side of a triangle. The magnetic field is provided by micro-magnets. The interaction among the electrons is described within an extended Hubbard Hamiltonian and electronic states are obtained using configuration interaction approach. The set of parameters is established for which the ground state of the molecule in a radial magnetic field is well approximated by a GHZ state.
description: 8 pages, 7 figures. Accepted for publication in PRB
Hampun kannabinoidituotteet.pdf
Creators: name: Saltiola, Tommi
Publisher: name: figshare
Year: 2022
Subjects: subject: 99901 Agricultural Engineering
subject: FOS: Other engineering and technologies
subject: 70106 Farm Management, Rural Management and Agribusiness
subject: FOS: Other agricultural sciences

description: There was a demand for marketing material and knowledge base for the cannabinoid products that the client Hamppumaa is reselling. The goal was to clarify the effects, possibilities, production, refining, markets and media conversation. There was not any finnish clarification about the cannabinoid industry so we wanted to translate what cannabinoid products are and what are their possibilities. The implementation method was a literature review on scientific studies and media articles. The results clarified the effects of cannabinoids, production related legislation in Finland and abroad, different processing methods and refining possibilities. Also including observations on cannabinoid markets and recent media conversations. Conclusion stated that cannabinoid products have market potential, health effects, changing legislative sitution and industrial possibilities in Finland.
Growth of massive black holes at their late stage
Creators: name: Xu, Ya-Di
name: Cao, Xinwu
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We derive the black hole mass density as a function of redshift with the bolometric luminosity function of AGN assuming that massive black holes grew via accreting the circumnuclear gases, in which the derived black hole mass density is required to match the measured local black hole mass density at z=0. ADAFs are supposed to present in low luminosity AGNs/normal galaxies, which are very hot and radiate mostly in the hard X-ray band. Most of the XRB is contributed by bright AGNs, and a variety of AGN population synthesis models were developed to model the observed XRB in the last two decades. Based on our derived black hole mass density, we calculate the contribution to the XRB from the ADAFs in faint AGNs/normal galaxies with a given Eddington ratio distribution, which is mostly in hard X-ray energy band with an energy peak at ~200 keV. The growth of massive black holes during ADAF phase can therefore be constrained with the observed XRB. Combining an AGN population synthesis model with our results, we find that the fitting on the observed XRB, especially at hard X-ray energy band with \ga 100 keV, is improved provided the contribution of the ADAFs in low luminosity AGNs/normal galaxies is properly included. It is found that less than ~15 per cent of local massive black hole mass density was accreted during ADAF phases. We suggest that more accurate measurements of the XRB in the energy band with \ga 100 keV in the future may help constrain the growth of massive black holes at their late stage. We also calculate their contribution to the extragalactic gamma-ray background, and find that less than ~1% of the observed EGRB is contributed by the ADAFs in these faint sources.
description: 9 pages, 11 figures, accepted for publication in ApJ.
Unusual PAH Emission in Nearby Early-Type Galaxies: A Signature of an Intermediate Age Stellar Population?
Creators: name: Vega, O.
name: Bressan, A.
name: Panuzzo, P.
name: Rampazzo, R.
name: Clemens, M.
name: Granato, G. L.
name: Buson, L.
name: Silva, L.
name: Zeilinger, W. W.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present the analysis of Spitzer-IRS spectra of four early-type galaxies, NGC 1297, NGC 5044, NGC 6868, and NGC 7079, all classified as LINERs in the optical bands. Their IRS spectra present the full series of H2 rotational emission lines in the range 5--38 microns, atomic lines, and prominent PAH features. We investigate the nature and origin of the PAH emission, characterized by unusually low 6 -- 9/11.3 microns inter-band ratios. After the subtraction of a passive early type galaxy template, we find that the 7 -- 9 microns spectral region requires dust features not normally present in star forming galaxies. Each spectrum is then analyzed with the aim of identifying their components and origin. In contrast to normal star forming galaxies, where cationic PAH emission prevails, our 6--14 microns spectra seem to be dominated by large and neutral PAH emission, responsible for the low 6 -- 9/11.3 microns ratios, plus two broad dust emission features peaking at 8.2 microns and 12 microns. Theses broad components, observed until now mainly in evolved carbon stars and usually attributed to pristine material, contribute approximately 30-50% of the total PAH flux in the 6--14 microns region. We propose that the PAH molecules in our ETGs arise from fresh carbonaceous material which is continuously released by a population of carbon stars, formed in a rejuvenation episode which occurred within the last few Gyr. The analysis of the MIR spectra allows us to infer that, in order to maintain the peculiar size and charge distributions biased to large and neutral PAHs, this material must be shocked, and excited by the weak UV interstellar radiation field of our ETG.
description: ApJ accepted
Security analysis and intrusion detection for embedded systems : a case study of smart meters
Creators: name: Molazem Tabrizi, Farid
Publisher: name: University of British Columbia
Year: 2017

description: Embedded systems are widely used in critical situations and hence, are targets for malicious users. Researchers have demonstrated successful attacks against embedded systems used in power grids, modern cars, and medical devices. Hence, it is imperative to develop techniques to improve security of these devices. However, embedded devices have constraints (such as limited memory capacity) that make building security mechanisms for them challenging. In this thesis, we formulate building Intrusion Detection System (IDS) for embedded systems as an optimization problem. We develop algorithms that, given the set of the security properties of the system and the invariants that verify those properties, build an IDS that maximizes the coverage for the security properties, with respect to the available memory. This allows our IDS to be applicable to a wide range of embedded devices with di erent memory capacities. Furthermore, we develop techniques to analyze security of both design and implementation of embedded systems. Given a set of capabilities of attackers, we automatically analyze the system and identify ways an adversary may tamper with the system. This will help developers discover new attacks, and improve the design and implementation of the system.
Laser phase noise effects on the dynamics of optomechanical resonators
Creators: name: Phelps, Gregory A.
name: Meystre, Pierre
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We investigate theoretically the influence of laser phase noise on the cooling and heating of a generic cavity optomechanical system. We derive the back-action damping and heating rates and the mechanical frequency shift of the radiation pressure-driven oscillating mirror, and derive the minimum phonon occupation number for small laser linewidths. We find that in practice laser phase noise does not pose serious limitations to ground state cooling. We then consider the effects of laser phase noise in a parametric cavity driving scheme that minimizes the back-action heating of one of the quadratures of the mechanical oscillator motion. Laser linewidths narrow compared to the decay rate of the cavity field will not pose any problems in an experimental setting, but broader linewidths limit the practicality of this back-action evasion method.
description: 9 pages, 7 figures
Signatures of spin-orbit interaction in transport properties of finite carbon nanotubes in a parallel magnetic field
Creators: name: del Valle, Miriam
name: Marganska, Magdalena
name: Grifoni, Milena
Publisher: name: Universität Regensburg
Year: 2011
Subjects: subject: 530 Physik

description: The transport properties of finite nanotubes placed in a magnetic field parallel to their axes are investigated. Upon including spin-orbit coupling and curvature effects, two main phenomena are analyzed that crucially depend on the tube’s chirality: (i) Finite carbon nanotubes in a parallel magnetic field may present a suppression of current due to the localization at the edges of otherwise conducting states. This phenomenon occurs due to the magnetic-field-dependent open boundary conditions obeyed by the carbon nanotube’s wave functions. The transport is fully suppressed above threshold values of the magnetic field, which depend on the nanotube chirality, length, and on the spin-orbit coupling. (ii) Reversible spin-polarized currents can be obtained upon tuning the magnetic field, exploiting the curvature-induced spin-orbit splitting.
Optimum estimate of delays and dispersive effects in low-frequency interferometric observations
Creators: name: Marti-Vidal, I.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Modern radio interferometers sensitive to low frequencies will make use of wide-band detectors. For such wide bandwidths, dispersive atmospheric effects introduce variations in the fringe delay which change through the band of the receivers. These undesired dispersive effects must be estimated and calibrated with the highest precision. We studied the achievable precision in the estimate of the ionospheric dispersion and the dynamic range of the correlated fringes for different distributions of sub-bands in low-frequency and wide-band interferometric observations. Our study is focused on the case of sub-bands with a bandwidth much narrower than that of the total covered spectrum (case of LOFAR). We computed the uncertainty of the ionospheric delay, the delay ambiguity, and the dynamic range of the fringes using four different kinds of sub-band distributions: constant spacing between sub-bands, random spacings, spacings based on a power-law distribution, and spacings based on Golomb rulers (sets of integers whose sets of differences have non-repeated elements). For a large number of sub-bands ($> 20$, depending on the delay window) spacings based on Golomb rulers give the most precise estimates of dispersive effects and the highest fringe dynamic ranges. Spacings based on the power-law distribution give similar results, although better than those with the Golomb rulers for smaller number of sub-bands. Random distributions result in large fringe dynamic ranges, but the estimate of dispersive effects is worse. A constant spacing of sub-bands results in very bad fringe dynamic ranges, but good estimates of ionospheric dispersion. Combining all the results, the power-law distribution gives the best compromise between homogeneity in the bandwidth sampling, precision in the estimate of ionospheric effects, dynamic range of the correlated fringes, and group-delay ambiguity.
description: 8 pages, 7 figures. Accepted for publication in A&A
Disentangling Inclusion in Primary Physical Education: Guidelines and Recommendations for Implementation
Creators: name: Heck, Sandra
name: Vecchione, Hannah
name: Steel, Elinor
name: Gallagher, Jackie
name: Holzweg, Martin
name: Scheuer, Claude
Publisher: name: Zenodo
Year: 2022
Subjects: primary education
physical education
inclusion
recommendations

description: The following guidelines and recommendations for implementation are based on an in-depth analysis of results of Intellectual Outputs produced in the frame of the current research project. The aim of this part of the DIPPE report is to have a retrospective view on the produced outputs and to provide recommendations for teachers on how they may use our products in the best possible way with the overarching aim to inclusive physical education practice, including all children in physical education classes.
Geometric scale invariance as a route to macroscopic degeneracy: loading a toroidal trap with a Bose or Fermi gas
Creators: name: Baillie, D.
name: Blakie, P. B.
name: Bradley, A. S.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: An easily scalable toroidal geometry presents an opportunity for creating large scale persistent currents in Bose-Einstein condensates, for studies of the Kibble-Zurek mechanism, and for investigations of toroidally trapped degenerate Fermi gases. We consider in detail the process of isentropic loading of a Bose or Fermi gas from a harmonic trap into the scale invariant toroidal regime that exhibits a high degree of system invariance when increasing the radius of the toroid. The heating involved in loading a Bose gas is evaluated analytically and numerically, both above and below the critical temperature. Our numerical calculations treat interactions within the Hartree-Fock-Bogoliubov-Popov theory. Minimal change in degeneracy is observed over a wide range of initial temperatures, and a regime of cooling is identified. The scale invariant property is further investigated analytically by studying the density of states of the system, revealing the robust nature of scale invariance in this trap, for both bosons and fermions. We give analytical results for a Thomas-Fermi treatment. We calculate the heating due to loading a spin-polarized Fermi gas and compare with analytical results for high and low temperature regimes. The Fermi gas is subjected to irreducible heating during loading, caused by the loss of one degree of freedom for thermalization.
description: 13 pages, 6 figures.
Hydrodynamics of the hydrocyclone flow field : effects of turbulence modelling, geometrical and design parameters
Creators: name: Zaman, Ehsan
Publisher: name: University of British Columbia
Year: 2017

description: This thesis describes a numerical study of the effect of swirl on the flow hydrodynamics in hydrocyclones and rotating pipes. Kinetic (force balance) and kinematic (velocity field) analysis were performed to identify the relative importance of turbulence, convective, and pressure forces in these flows. We showed that convective and pressure forces in hydrocyclones are three orders of magnitude larger than the size of turbulent forces, and seven orders of magnitude greater than the viscous forces. We derived a new dimensionless parameter based on a ratio of Euler numbers that gave a unique relationship for pressure along the axis of a hydrocyclone for all the cone angles tested. This finding enables rigorous scaling of hydrocyclones of differing cone angles. A complementary numerical study of flow in rotating pipes was carried out to elucidate the relative importance of convection and turbulence. We identified a dimensionless rotation parameter that delineates the condition at which decreasing turbulence force equals increasing convective force as rotational speed increases. This dimensionless number establishes a criterion for knowing which forces are dominant, and thereby a rational basis for choosing CFD (Computational Fluid Dynamics) models that are both cost-effective and accurate. Lastly, we conducted a sensitivity study to determine the effects of varying values of constants in the quadratic pressure-strain (QPS) Reynolds Stress turbulence model (RSM) for CFD modelling of swirl in hydrocyclones. The results identified the changes necessary to attain accurate predictions, such as overcoming the under-prediction problems of RSM. In addition, these findings laid the groundwork for a swirl-specific turbulence model for hydrocyclones.
Crazy heart: kinematics of the "star pile" in Abell 545
Creators: name: Salinas, Ricardo
name: Richtler, Tom
name: West, Michael J.
name: Romanowsky, Aaron J.
name: Lloyd-Davies, Ed
name: Schuberth, Ylva
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We study the structure and internal kinematics of the "star pile" in Abell 545 - a low surface brightness structure lying in the center of the cluster.We have obtained deep long-slit spectroscopy of the star pile using VLT/FORS2 and Gemini/GMOS, which is analyzed in conjunction with deep multiband CFHT/MEGACAM imaging. As presented in a previous study the star pile has a flat luminosity profile and its color is consistent with the outer parts of elliptical galaxies. Its velocity map is irregular, with parts being seemingly associated with an embedded nucleus, and others which have significant velocity offsets to the cluster systemic velocity with no clear kinematical connection to any of the surrounding galaxies. This would make the star pile a dynamically defined stellar intra-cluster component. The complicated pattern in velocity and velocity dispersions casts doubts on the adequacy of using the whole star pile as a dynamical test for the innermost dark matter profile of the cluster. This status is fulfilled only by the nucleus and its nearest surroundings which lie at the center of the cluster velocity distribution.
description: Accepted for publication in A&A. 10 pages & 6 figures
Synthese und strukturelle Charakterisierung von Bis(pentamethylcyclopentadienylmolybdän-μ-sulfido)-Komplexen mit μ,η1-SSR-Liganden(= SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF BIS(PENTAMETHYLCYCLOPENTADIENYLMOLYBDENUM-MU-SULFIDO) COMPLEXES WITH MU,ETA-1-SSR LIGANDS)
Creators: name: Brunner, Henri
name: Grassl, R.
name: Wachter, Joachim
name: Nuber, B.
name: Ziegler, M. L.
Publisher: name: Universität Regensburg
Year: 1992
Subjects: subject: 540 Chemie

description: The reaction of Cp2*Mo2S4I2(Cp* = eta(5)-C5Me5) with two equivalents of NaSR (R = Me, (i)Pr, (t)Bu, Ph) gives the complexes Cp2*Mo2(mu,eta(1)-SSR)2(mu-S)2 (2a-d) in nearly quantitative yields. The compounds have been investigated spectroscopically and in the case of R = Ph (2d) by means of X-ray diffraction analysis. The results show the presence of two eta(1)-PhSS- bridges (d(s-s) 2.139(2) angstrom) and that exclusively the trans-isomer is formed. All sulfur atoms lie in one plane perpendicular to the Mo-Mo axis and bisecting it.
The WFC3 Galactic Bulge Treasury Program: Metallicity Estimates for the Stellar Population and Exoplanet Hosts
Creators: name: Brown, Thomas M.
name: Sahu, Kailash
name: Anderson, Jay
name: Tumlinson, Jason
name: Valenti, Jeff A.
name: Smith, Ed
name: Jeffery, Elizabeth J.
name: Renzini, Alvio
name: Zoccali, Manuela
name: Ferguson, Henry C.
name: VandenBerg, Don A.
name: Bond, Howard E.
name: Casertano, Stefano
name: Valenti, Elena
name: Minniti, Dante
name: Livio, Mario
name: Panagia, Nino
Publisher: name: arXiv
Year: 2010
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present new UV-to-IR stellar photometry of four low-extinction windows in the Galactic bulge, obtained with the Wide Field Camera 3 on the Hubble Space Telescope (HST). Using our five bandpasses, we have defined reddening-free photometric indices sensitive to stellar effective temperature and metallicity. We find that the bulge populations resemble those formed via classical dissipative collapse: each field is dominated by an old (~10 Gyr) population exhibiting a wide metallicity range (-1.5 < [Fe/H] < 0.5). We detect a metallicity gradient in the bulge population, with the fraction of stars at super-solar metallicities dropping from 41% to 35% over distances from the Galactic center ranging from 0.3 to 1.2 kpc. One field includes candidate exoplanet hosts discovered in the SWEEPS HST transit survey. Our measurements for 11 of these hosts demonstrate that exoplanets in the distinct bulge environment are preferentially found around high-metallicity stars, as in the solar neighborhood, supporting the view that planets form more readily in metal-rich environments.
description: Accepted for publication in The Astrophysical Journal Letters. Latex, 5 pages, ApJ format
Preparative, structural, and electrochemical investigations on peralkylated niobocene dichlorides and difluorides
Creators: name: Brunner, Henri
name: Gehart, G.
name: Meier, Walter
name: Wachter, Joachim
name: Riedel, Astrid
name: Elkrami, S.
name: Mugnier, Y.
name: Nuber, B.
Publisher: name: Universität Regensburg
Year: 1994
Subjects: subject: 540 Chemie

description: CP(dagger)2NbCl2 (CP(dagger) = 175-C5Me4Et) (1b) was synthesized from NbCl5 and a slight excess of Cp(dagger)Li and NaBH4. Its electrochemical (2 e-, E1/2 = -1.6 V) and chemical reduction (2 equiv of Na/Hg) was studied showing that peralkylation of the Cp ligand facilitates two-electron reduction compared to less substituted CP2NbHal2 derivatives. The reduced solutions of CP*2NbCl2 (CP* = C5Me5) (1a) and of lb were shown by means of EPR spectroscopy to contain two new paramagnetic species 1A,B for which bent niobocene (A(Nb) = 100 G) and fulvene-like structures (A(Nb) = 55 G) are proposed. The high reduction potential of these species led in their reaction with HPF6 to the first stable difluoroniobocene derivative, [CP(dagger)2NbF2]PF6 (2), in good yield. The molecular structures of 2 and a cocrystallizate of 2 and [CP(dagger)2NbCl2]PF6 (3), analyzing as [CP(dagger)2NbCl(Cl,F)]PF6 (4), were studied by X-ray diffraction techniques. Comparison with the structure of 1b shows a marked decrease of the angle Hal-Nb-Hal from 102.3(4)-degrees (2) to 85.2(1)-degrees (1b). Electrochemical 1 e- reduction of 2 gave rise to the formation of CP(dagger)2NbF2, which exhibits a much lower potential (E1/2 = -2.38 V) than other niobocene dihalides. Reaction of 2 with Li2S2 gave CP(dagger)2Nb(eta-S2)F, whereas 3 was reduced by Li2S2 to give 1b.
Distance covariance in metric spaces
Creators: name: Lyons, Russell
Publisher: name: arXiv
Year: 2011
Subjects: subject: Statistics Theory (math.ST)
subject: Metric Geometry (math.MG)
subject: Probability (math.PR)
subject: FOS: Mathematics

description: We extend the theory of distance (Brownian) covariance from Euclidean spaces, where it was introduced by Székely, Rizzo and Bakirov, to general metric spaces. We show that for testing independence, it is necessary and sufficient that the metric space be of strong negative type. In particular, we show that this holds for separable Hilbert spaces, which answers a question of Kosorok. Instead of the manipulations of Fourier transforms used in the original work, we use elementary inequalities for metric spaces and embeddings in Hilbert spaces.
description: Published at http://dx.doi.org/10.1214/12-AOP803 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org). This version has appended the two published errata as well
The Reaction of [CP2+NB2(B2H6)2] (CP+ = ETA-ETME4C5) with Sulfur: Stabilization of the Tetrathioborato Ligand in Novel Sulfido Niobium Clusters
Creators: name: Brunner, Henri
name: Gehart, G.
name: Nuber, B.
name: Wachter, Joachim
name: Ziegler, M. L.
Publisher: name: Universität Regensburg
Year: 1992
Subjects: subject: 540 Chemie

description: An equilateral Nb3 triangle the edges of which are spanned by a BS4 tetrahedron and bridged by sulfido ligands on the ``underside'' is found in cluster 1. The synthesis of this cluster with an unusual electron configuration shows that tetrathioborates can serve as ligands in organometallic chemistry. Cp+ = eta-5-EtMe4C5.
HPA Bestfitting InceptionV3
Creators: name: Shubin Dai
Publisher: name: Zenodo
Year: 2022
Subjects: bioimage.io
bioimage.io:model
classification
inception-v3
hpa
onnx
cells
protein-localization

description: Download RDF Package
HPA Bestfitting Densenet The winning model of HPA image classification 2019 by Bestfitting Source code: https://github.com/CellProfiling/HPA-competition-solutions/tree/master/bestfitting
description: The winning model of HPA image classification 2021 by Bestfitting (Uploaded via https://bioimage.io)
Three-dimensional negative index of refraction at optical frequencies by coupling plasmonic waveguides
Creators: name: Verhagen, Ewold
name: de Waele, René
name: L.
name: Kuipers
name: Polman, Albert
Publisher: name: arXiv
Year: 2010
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We identify a route towards achieving a negative index of refraction at optical frequencies based on coupling between plasmonic waveguides that support backwards waves. We show how modal symmetry can be exploited in metal-dielectric waveguide pairs to achieve negative refraction of both phase and energy. By properly controlling coupling between adjacent waveguides, a metamaterial consisting of a one-dimensional multilayer stack exhibiting an isotropic index of -1 can be achieved at a free-space wavelength of 400 nm. The general concepts developed here may inspire new low-loss metamaterial designs operating close to the metal plasma frequency.
description: 8 pages, 7 figures
Spontaneous Emergence of Persistent Spin Helix from Homogeneous Spin Polarization
Creators: name: Slipko, V. A.
name: Savran, I.
name: Pershin, Y. V.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We demonstrate that a homogeneous spin polarization in one-dimensional structures of finite length in the presence of Bychkov-Rashba spin-orbit coupling decays spontaneously toward a persistent spin helix. The analysis of formation of spin helical state is presented within a novel approach based on a mapping of spin drift-diffusion equations into a heat equation for a complex field. Such a strikingly different and simple method allows generating robust spin structures whose properties can be tuned by the strength of the spin orbit interaction and/or structure's length. We generalize our results for two-dimensional case predicting formation of persistent spin helix in two-dimensional channels from homogeneous spin polarization.
Stepping Stones: Our journey towards a culture of Open Research
Creators: name: Schwamm, Hardy
name: Sendall, Joshua
Publisher: name: Zenodo
Year: 2019
Subjects: Open Research
Open Science
Open Scholarship
Culture Change
Community Building

description: Presentation slides used on 21 March 2019 at the Research Libraries UK Conference (RLUK19). The abstract of the paper: This paper summarises Lancaster University’s three-stage strategy to promote a culture of Open Research across the institution. Our culture change journey began with Data Conversations, which are designed for researchers from all disciplines and career stages to share their experiences of collecting, managing and sharing research data. Data Conversations has been a success story so far. We have organised six events with increasing attendance numbers and consistently positive feedback. As our second step, the Library has co-founded the Open Research Café with PROSPR, a grass roots open research community from our Psychology department. The Open Research Café widens the scope from Research Data Management best practice to all aspects of Open Research. As a third step, we are establishing a bottom-up dialogue with the University’s senior management by creating a Forum for Open Research (FOR). The aims are to suggest and promote Open Research initiatives to senior stakeholders in the institution and raise awareness of Open Research. Our journey demonstrates the evolving role that libraries can play in “creating new types of service to support changing practices in research” (SCONUL p.18) and we believe that this approach could be replicated at other institutions.
Evidence of local structural inhomogeneity in FeSe(1-x)Te(x) from extended x-ray absorption fine structure
Creators: name: Joseph, B.
name: Iadecola, A.
name: Puri, A.
name: Simonelli, L.
name: Mizuguchi, Y.
name: Takano, Y.
name: Saini, N. L.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Local structure of FeSe(1-x)Te(x) has been studied by extended x-ray absorption fine-structure (EXAFS) measurements as a function of temperature. Combination of Se and Fe K edge EXAFS has permitted to quantify the local interatomic distances and their mean-square relative displacements. The Fe-Se and Fe-Te bond lengths in the ternary system are found to be very different from the average crystallographic Fe-Se/Te distance, and almost identical to the Fe-Se and Fe-Te distances for the binary FeSe and FeTe systems, indicating distinct site occupation by the Se and Te atoms. The results provide a clear evidence of local inhomogeneities and coexisting electronic components in the FeSe1-xTex, characterized by different local structural configurations, with direct implication on the fundamental electronic structure of these superconductors.
description: http://link.aps.org/doi/10.1103/PhysRevB.82.020502
Präparative, 11B-, 93Nb-NMR-spektroskopische und strukturelle Untersuchungen an Cp2NbBH4- und [CpNb(B2H6)]2-Komplexen (= PREPARATORY ANALYSIS, B-11 NMR-SPECTROSCOPY, NB-93 NMR-SPECTROSCOPY AND STRUCTURAL-ANALYSIS OF CP2NBBH4 COMPLEXES AND [CPNB(B2H6)] COMPLEXES)
Creators: name: Brunner, Henri
name: Gehart, G.
name: Meier, W.
name: Wachter, Joachim
name: Wrackmeyer, B.
name: Nuber, B.
name: Ziegler, M. L.
Publisher: name: Universität Regensburg
Year: 1992
Subjects: subject: 540 Chemie

description: NbCl5 reacts with NaBH4 and LiCp+ (Cp+ = EtMe4C5) dependent on the stoichiometry and temperature to give Cp+2NbCl2 (1), CP+2Nb2Cl2(B2H6)(2), CP+2NbBH4(3a) and Cp+ 2Nb2(B2H6)2 (4a). With a large excess of NaBH4, Cp+ 2NbCl2 gives 2 at 25-degrees-C, which reacts further with NaBH 4 to give 4a. The synthesis of the deep violet, very stable 4a can be generalised by using C5Me5Li and tBUC5H4Li, respectively. Compounds 1-4 are characterised by means of IR, H-1, and heteroatom NMR spectra. An X-ray structure analysis was carried out with 4a. Whereas 1 and 3 are analogous to already known complexes, in 2 and 4a the B2H, dianion (which is not stable in the free state) is present as a bridging ligand, oriented perpendicularly with respect to the Nb-Nb axis. So far, the highest nuclear magnetic Nb-93 shielding has been observed for compounds 4, extending the range of known delta(Nb-93) values by 2500 ppm. The temperature dependence of the linewidths of both the B-11 and the Nb-93 NMR signals of 4c allows evaluation of the magnitude of J((NbB)-Nb-93-B-11 = 50 +/- 10 Hz.
DataCite Service Providers Showcase - 4Science
Creators: name: Mornati, Susanna
name: Bollini, Andrea
Publisher: name: Zenodo
Year: 2021
Subjects: DataCite Member Meeting 2021
Service Provider
DOI
Dataverse
DSpace
OJS

description: DataCite launched its registered service providers program in 2020, in order to ensure that members have access to high-quality DataCite integrations that support DOI registration best practices. To date, 10 developers/vendors have been registered https://datacite.org/service-providers.html (and more are on on the way!)
 This presentation by Susanna Mornati (4Science) provides updates about DSpace, Dataverse and OJS. A recording of the presentation can be found at: https://youtu.be/O0uOLgsqZ2U?t=645