cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Classical density functional theory, unconstrained crystallization, and polymorphic behavior
Creators: name: Lutsko, James F.
name: Lam, Julien
Publisher: name: arXiv
Year: 2018
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: While in principle, finite temperature density functional theory (ftDFT) should be a powerful tool for the study of crystallization, in practice this has not so far been the case. Progress has been hampered by technical problems which have plagued the study of the crystalline systems using the most sophisticated Fundamental Measure Theory models. In this paper, the reasons for the difficulties are examined and it is proposed that the tensor functionals currently favored are in fact numerically unstable. By reverting to an older, more heuristic model it is shown that all of the technical difficulties are eliminated. Application to a Lennard-Jones fluid results in a demonstration of power of ftDFT to describe crystallization in a highly inhomogeneous system. First, we show that droplets attached to a slightly hydrophobic wall crystallize spontaneously upon being quenched. The resulting crystallites are clearly faceted structures and are predominantly HCP structures. In contrast, droplets in a fully periodic calculational cell remain stable to lower temperatures and eventually show the same spontaneous localization of the density into 'atoms' but in an amorphous structure having many of the structural charactersitics of a glass. A small change of the protocol leads, at the same temperature, to the formation of crystals, this time with the FCC structure typical of bulk Lennard-Jones solids. The FCC crystals have lower free energy than the amorphous structures which in turn are more stable than the liquid droplets. It is demonstrated that as the temperature is raised, the free energy differences between the structures decreases until the solid clusters become less stable than the liquid droplets and spontaneously melt. The presence of energy barriers separating the various structures is therefore clearly demonstrated.
Reminiscences of Claude L. Pickens, Jr., 1982
Publisher: name: Columbia University
Year: 2020
Subjects: Clergy
Missionaries--China
Missions--China

description: Experiences in China as a missionary 1926-1950; work for the National Council of Churches 1950-1952; personal recollections of Bishop Sherrill; views on Chiang Kai-shek
Correlation Between Energy Spectral States and Fast Time Variability and Further Evidence for the Marginally Stable Orbit in 4U 1820-30
Creators: name: Zhang, W.
name: Strohmayer, A. P. Smale T. E.
name: Swank, J. H.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We report results from a long-term monitoring data set obtained with the Rossi X-ray Timing Explorer (RXTE) from the bright globular cluster binary source 4U 1820-30. During this monitoring, the source intensity varied from a flux of 2.9E-9 ergs/cm**2/s to 8.5E-9 ergs/cm**2/s in the 2-10 keV band, which correspond to, respectively, a count rate of 1,600 cps and 4,500 cps in the nominal 2-60 keV RXTE-PCA band. Its energy spectral state was observed to encompass both the banana branches and the island state. Kilohertz QPOs were observed to exist in the upper-banana and lower-banana branches, as well as in the island state. In particular, we report that the kHz QPOs were present only when the soft-color (defined as the flux ratio of the 3.9-5.0 keV band to the 1.7-3.9 keV band) was below 0.78 without regard to the overall count rate and without regard to whether the source is in any one of the three branches or states. Their centroid frequency was well correlated with the overall count rate below 2,500 cps. When the count rate was above 2,500 cps, the QPO frequency was consistent with a constant independent of the overall count rate. We take this as further evidence that the inner edge of the accretion had reached the marginally stable orbit, and therefore the constant 1060 +/- 20 Hz is the marginally stable orbit frequency.
description: 7 pages, LaTex (aas2pp4), Accepted for publication in ApJ Lett
Reminiscences of Claude Moore Fuess, 1962
Publisher: name: Columbia University
Year: 2021
Subjects: Educators
School administrators
Private schools--United States
Education, Secondary

description: Preparatory school teaching; headmastership at Andover; abolition of fraternities, distinguished Andover graduates; literary recollections and impressions; comments on historians; impressions of Alfred Stearns, Henry Cabot Lodge, Endicott Peabody, Calvin Coolidge, Henry L. Stimson
Statistical methods for monitoring multiple data streams
Creators: name: Lau, Fatih Din-Houn
Publisher: name: Imperial College London
Year: 2014

description: This thesis develops new methods to monitor multiple data streams and report some quantity of interest over time. We consider two types of settings. First, we consider a data stream as realisations from a sequence of independent random variables that are revealed over time. To monitor the individual streams, we propose a new type of control chart, based on the cumulative sum chart. Cumulative sum charts are typically used to detect a change in the distribution of a sequence of observations, e.g., shifts in the mean. Usually, after signalling, the chart is restarted by setting it to some value below the signalling threshold. We propose a non-restarting cumulative sum chart which is able to detect periods during which the stream is out of control. Further, we advocate an upper boundary to prevent the cumulative sum chart rising too high, which helps to detect a change back into control. We prove that the non-restarting charts are optimal, in a well-defined sense. Further, we investigate the performance of these charts when the upper boundary is varied. Simulation results show a trade-off between the height of the upper boundary of the chart and the false signal rate. We then present an algorithm to control the false discovery rate across multiple data streams using the non-restarting charts. We consider two definitions of a false discovery: signalling out-of-control when the observations have been in-control since the start and signalling out-of-control when the observations have been in-control since the last time the chart was at zero. We prove that the false discovery rate is controlled under both these definitions simultaneously. Simulations reveal the difference in false discovery rate control when using these and other desirable definitions of a false discovery. In the second setting, a data stream is considered as observations of a Bayesian model revealed over time. The aim is to report a posterior summary of interest quickly and within a user-specified degree of accuracy. A system is presented to tackle such problems. The estimates are calculated using weighted samples stored in a database. The stored samples are maintained such that the accuracy of the estimates and quality of the samples is satisfactory. This maintenance involves varying the number of samples in the database and updating their weights. New samples are generated, when required, by a Markov chain Monte Carlo algorithm. The system is demonstrated using a football league model that is used to predict the end of season table. Correctness of the estimates and their accuracy is shown in a simulation using a linear Gaussian model. Lastly, potential improvements of the system are investigated. A series of motivating simulations illustrate some potential problems of the system. Remedial solutions are suggested, with a view toward implementation in the near future.
VALHYBIO cruise,Alis R/V
Creators: name: Cécile, DUPOUY
Publisher: name: Sismer
Year: 2008

description: L'objectif de la campagne VALHYBIO était de recueillir des mesures synoptiques de la « couleur de l'eau » in situ (propriétés optiques et pigments) pour valider un algorithme de calcul de la chlorophylle en milieu lagonaire, avec correction de l'effet de la réflectance du fond. L'idée était de parcourir un réseau de 53 stations représentatives des différents types de fonds et incluant des stations de référence à l'extérieur de la barrière corallienne, si possible dans des conditions de vents différentes. Trois points fixes de 24h  représentatifs (entre les cornes du lagon sud, canyon profond, et bande côtière) devaient améliorer notre connaissance de la variabilité à court terme (marée, vent). L'instrumentation utilisée devait permettre des mesures suffisamment sensibles pour les faibles concentrations des eaux tropicales oligotrophes. Pour cela, une combinaison originale d'instruments, parfois prototypes, était prévue. Les données satellitaires MODIS étaient traitées en temps réel. L'objectif final du projet PNTS VALHYBIO était d'utiliser les données de ce capteur pour valider les simulations du modèle bio-géochimique couplé (Dupouy et al., 2008a, Dupouy, 2008).
Multi-agent based simulation of self-governing knowledge commons
Creators: name: Macbeth, Samuel
Publisher: name: Imperial College London
Year: 2014

description: The potential of user-generated sensor data for participatory sensing has motivated the formation of organisations focused on the exploitation of collected information and associated knowledge. Given the power and value of both the raw data and the derived knowledge, we advocate an open approach to data and intellectual-property rights. By treating user-generated content as well as derived information and knowledge as a common-pool resource, we hypothesise that all participants can be compensated fairly for their input. To test this hypothesis, we undertake an extensive review of experimental, commercial and social participatory-sensing applications, from which we identify that a decentralised, community-oriented governance model is required to support this open approach. We show that the Institutional Analysis and Design framework as introduced by Elinor Ostrom, in conjunction with a framework for self-organising electronic institutions, can be used to give both an architectural and algorithmic base for the necessary governance model, in terms of operational and collective choice rules specified in computational logic. As a basis for understanding the effect of governance on these applications, we develop a testbed which joins our logical formulation of the knowledge commons with a generic model of the participatory-sensing problem. This requires a multi-agent platform for the simulation of autonomous and dynamic agents, and a method of executing the logical calculus in which our electronic institution is specified. To this end, firstly, we develop a general purpose, high performance platform for multi-agent based simulation, Presage2. Secondly, we propose a method for translating event-calculus axioms into rules compatible with business rule engines, and provide an implementation for JBoss Drools along with a suite of modules for electronic institutions. Through our simulations we show that, when building electronic institutions for managing participatory sensing as a knowledge commons, proper enfranchisement of agents (as outlined in Ostrom's work) is key to striking a balance between endurance, fairness and reduction of greedy behaviour. We conclude with a set of guidelines for engineering knowledge commons for the next generation of participatory-sensing applications.
Voluta musica Linnaeus, 1758, spec. nov.
Creators: name: Linnaeus, Carolus
Publisher: name: Laurentius Salvius
Year: 1758
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Neogastropoda
Volutidae
Voluta
Voluta musica

description: Voluta musica [spec. nov.]
V. testa fusiformi, anfractibus spinis obtusis, columella octoplicata.
Bonan. recr. 3. t. 296, 297.
Gvalt. test. t. 28. f. X. Z.
Argenv. conch. t. 17. f. F. Papyrus musica.
Habitat in O. Americae ad Jamaicam, Barbados.
description: Published as part of Linnaeus, Carolus, 1758, Systema Naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Stockholm :Laurentius Salvius on page 733, DOI: 10.5962/bhl.title.542, http://zenodo.org/record/3922206
Keplerian Squeezed States and Rydberg Wave Packets
Creators: name: Bluhm, Robert
name: Kostelecky, Alan
name: Tudose, Bogdan
Publisher: name: arXiv
Year: 1995
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We construct minimum-uncertainty solutions of the three-dimensional Schrödinger equation with a Coulomb potential. These wave packets are localized in radial and angular coordinates and are squeezed states in three dimensions. They move on elliptical keplerian trajectories and are appropriate for the description of the corresponding Rydberg wave packets, the production of which is the focus of current experimental effort. We extend our analysis to incorporate the effects of quantum defects in alkali-metal atoms, which are used in experiments.
description: accepted for publication in Physical Review A
Selectivity and deactivation in the single-stage synthesis of dimethyl ether from CO2/CO/H2
Creators: name: Montesano Lopez, Raúl
Publisher: name: Imperial College London
Year: 2014

description: The selectivity and stability of catalysts for the single-stage production of dimethyl ether from gas mixtures containing CO2, CO and H2 is studied. A Cu/ZnO/Al2O3 catalyst was used for the hydrogenation of carbon oxides while the dehydration of methanol was catalysed by γ-alumina, phosphated γ-alumina or protonic zeolites. The influence that the proximity between the methanol synthesis and the methanol dehydration functions has on the catalytic stability is evaluated for each catalyst pair under different feed compositions. The assessment of the effect of zeolite topology on the deactivation and the by-product formation is also aimed. The intimate contact between Cu/ZnO/Al2O3 and γ-alumina is found to cause fast deactivation on both catalysts during the first hours of the experimental runs. It is shown that the detrimental interaction is more severe under CO-rich conditions than for gas mixtures with high CO2 contents. The addition of phosphorus to the γ-alumina up to the monolayer capacity mediates the loss of activity that occurs in the presence of high CO concentrations. The independent characterisation of the spent catalysts gives insights on the mechanism responsible for the observed loss of activity . Five different zeolite structures were considered to be studied as dehydration catalysts: mordenite, ZMS-5, ferrierite, theta-1 and ZSM-23. It is found that the deactivation of zeolites during the single-stage synthesis of DME is dictated by the deposition of carbon residues which is related to the topology of the solid acid. In the conversion of CO/H2, the hydrocarbon distribution depends on the nature of the entrained organics and it is demonstrated that a careful selection of crystallite size and channel structure of the zeolite allows the conversion and selectivity to be controlled. Under CO2 and H2, ZSM-5 is shown to be considerably more active than γ-alumina and very selective towards dimethyl ether. Experiments using different SiO2 to Al2O3 ratios indicate that the deactivation depends on the acid site density rather than on the acid strength.
The eclipsing supersoft X-ray binary CAL 87
Creators: name: Hutchings, J. B.
name: Crampton, D.
name: Cowley, A. P.
name: Schmidtke, P. C.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present and discuss 25 spectra obtained in November 1996, covering all phases of the CAL 87 binary system. These spectra are superior both in signal-to-noise and wavelength coverage to previously published data so that additional spectral features can be measured. Photometry obtained on the same nights is used to confirm the ephemeris and to compare with light curves from previous years. Analysis of the color variation through the orbital cycle has been carried out using archival MACHO data. When a barely resolved red field star is accounted for, there is no (V-R)-color variation, even through eclipse. There have been substantial changes in the depth of minimum light since 1988; it has decreased more than 0.5 mag in the last several years. The spectral features and radial velocities are also found to vary not only through the 0.44-day orbit but also over timescales of a year or more. Possible interpretations of these long-term changes are discussed. The 1996 spectra contain phase-modulated Balmer absorption lines not previously seen, apparently arising in gas flowing from the region of the compact star. The changes in emission-line strengths with orbital phase indicate there are azimuthal variations in the accretion disk structures. Radial velocities of several lines give different amplitudes and phasing, making determination of the stellar masses difficult. All solutions for the stellar masses indicate that the companion star is considerably less massive than the degenerate star. The Balmer absorption-line velocities correspond to masses of ~1.4Msun for the degenerate star and ~0.4Msun for the mass donor. However, the strong He II emission lines indicate a much more massive accreting star, with Mx>4Msun.
description: 18 pages including tables, plus10 figures. To appear in ApJ
Axiomatic Quantum Theory
Creators: name: Luecke, W.
Publisher: name: arXiv
Year: 1995
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A rough overview is given over the most essential structures underlying all working quantum theoretical models as well as axiomatic and algebraic quantum field theory .
description: 29 pages, LaTeX, e-mail address corrected
Reminiscences of Clement Conger 1972
Publisher: name: Columbia University
Year: 2020
Subjects: Government executives--United States

description: Assistant director, Bureau of German Affairs, 1949-1954; Assistant Chief of Protocol, 1955-1957; Deputy Chief of Protocol, 1958-1961; early life and career; air travel in 1950s; official visits of Shah of Iran and King of Morocco
Scheme invariants in phi^4 theory in four dimensions
Creators: name: Jack, I.
name: Poole, C.
Publisher: name: arXiv
Year: 2018
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We provide an analysis of the structure of renormalisation scheme invariants for the case of $ϕ^4$ theory, relevant in four dimensions. We give a complete discussion of the invariants up to four loops and include some partial results at five loops, showing that there are considerably more invariants than one might naively have expected. We also show that one-vertex reducible contributions may consistently be omitted in a well-defined class of schemes which of course includes MSbar.
description: Uses tikz; revised version with minor errors corrected
EPR-Bell Nonlocality, Lorentz Invariance, and Bohmian Quantum Theory
Creators: name: Berndl, K.
name: Duerr, D.
name: Goldstein, S.
name: Zanghi, N.
Publisher: name: arXiv
Year: 1995
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We discuss the problem of finding a Lorentz invariant extension of Bohmian mechanics. Due to the nonlocality of the theory there is (for systems of more than one particle) no obvious way to achieve such an extension. We present a model invariant under a certain limit of Lorentz transformations, a limit retaining the characteristic feature of relativity, the non-existence of absolute time resp. simultaneity. The analysis of this model exemplifies an important property of any Bohmian quantum theory: the quantum equilibrium distribution $ρ= |ψ|^2$ cannot simultaneously be realized in all Lorentz frames of reference.
description: 24 pages, LaTex, 4 figures
The circumstellar shell of the post-AGB star HD 56126: the 12C12C/12C13C isotope ratio and 12C16O column density
Creators: name: Bakker, Eric J.
name: Lambert, David L.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We have made the first detection of circumstellar absorption lines of the 12C13C (Phillips) system 1-0 band and the 12C16O first-overtone 2-0 band in the spectrum of the post-AGB star HD56126 (IRAS07134+1005). The rotational temperatures are lower for molecules with a higher permanent dipole moment. Derived relative column densities ratios are 12C12C/12C13C=36+-13, 12C16O/(12C12C+12C13C)=606+-230, and 12C16O/(12C14N+13C14N)=475+-175. The isotopic exchange reaction for 12C12C is too slow to significantly alter the 12C12C/12C13C ratio and the 12C12C to 12C13C ratio a good measure of half the carbon isotope ratio: 12C/13C=2 X 12C12C/12C13C=72+-26. A fit of the 12C12C excitation model of van Dishoeck & Black (1982) to the relative population distribution of 12C12C yields n sigma / I = 3.3 +- 1.0 X 1e-14. At r=1e16cm this translates in n=1.7e7cm-3 and dM/dt=2.5e-4Msol/year.
description: 21 pages, submitted to ApJ, 3 figures
Reminiscences of Claudia Moore Read 1979
Publisher: name: Columbia University
Year: 2019
Subjects: Dancers
Dance teachers
Modern dance

description: Physical education and dance training at University of North Carolina at Greensboro, 1930-1934; Bennington Summer School of the Dance, 1934: classes with Graham, Humphrey, Holm and Hill, Dalcroze Eurhythmics; teaching summer school techniques at University of Nebraska; studies at Mary Wigman School, Germany, summer of 1936; Bennington Summer School of the Dance, 1938: inter-company rivalries, PASSACAGLIA; Mills College Summer School, 1939; Bennington Summer School of the Arts, 1940-1942; DECADE; importance and demise of Bennington Summer School; reminiscences of Doris Humphrey, Charles Weidman and many others.
RWang_tables_figures_ESM.pdf from Loss of top-down biotic interactions changes the relative benefits for obligate mutualists
Creators: name: Wang, Rong
name: Chen, Xiao-Yong
name: Chen, Yan
name: Wang, Gang
name: W. Dunn, Derek
name: J. Quinnell, Rupert
name: G. Compton, Stephen
Publisher: name: The Royal Society
Year: 2019

description: The collapse of mutualisms due to anthropogenic changes is contributing to losses of biodiversity. Top predators can regulate biotic interactions between species at lower trophic levels and may contribute to the stability of such mutualisms, but they are particularly likely to be lost after disturbance of communities. We focused on the mutualism between the fig tree Ficus microcarpa and its host-specific pollinator fig wasp and compared the benefits accrued by the mutualists in natural and translocated areas of distribution. Parasitoids of the pollinator were rare or absent outside the natural range of the mutualists, where the relative benefits the mutualists gained from their interaction were changed significantly away from the plant's natural range due to reduced seed production rather than increased numbers of pollinator offspring. Furthermore, in the absence of the negative effects of its parasitoids, we detected an oviposition range expansion by the pollinator, with the use of a wider range of ovules that could otherwise have generated seeds. Loss of top-down control has therefore resulted in a change in the balance of reciprocal benefits that underpins this obligate mutualism, emphasizing the value of maintaining food web complexity in the Anthropocene.
MPEC 2024-G108 : 2024 GP1
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2024 GP1

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
medigan_packages
Creators: name: Noussair Lazrak, Richard Osuala
Publisher: name: Zenodo
Year: 2021

description: MediGAN is a Python library to implement Generative Adversarial Networks(GANs), Conditional GANs, Adversarial Auto-Encoders(AAEs) etc This library aims to enhance data augmentation via providing/ generating training data sets for other Deep learning models. Dependencies
 numpy:
 PyTorch import medigan as datasets dataset = datasets.DCGAN(root="dataset/", transform=transforms, download=True)
 #generate_dataset("malign_mass_gen_DCGAN","Generated with DCGAN") #generate_dataset("malign_mass_gen_DCGAN","generated_with_mass_dcgan") #print (get_meta_data("malign_mass_gen_DCGAN","performance"))
Voluta vespertilio Linnaeus, 1758, spec. nov.
Creators: name: Linnaeus, Carolus
Publisher: name: Laurentius Salvius
Year: 1758
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Neogastropoda
Volutidae
Voluta
Voluta vespertilio

description: Voluta vespertilio [spec. nov.]
V. testa fusiformi, anfractibus spinis acutis, columella quadriplicata.
Bonan. recr. 3. t. 294.
Rumph. mus. t. 32. f. H. Vespertilio.
Gvalt. test. t. 28. f. G.
Habitat in O. utriusque Indiae.
description: Published as part of Linnaeus, Carolus, 1758, Systema Naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Stockholm :Laurentius Salvius on page 733, DOI: 10.5962/bhl.title.542, http://zenodo.org/record/3922206
Reminiscences of Clifford Judkins Durr, 1974
Publisher: name: Columbia University
Year: 2021
Subjects: Lawyers
New Deal, 1933-1939
Broadcasting policy
Internal security--United States
Practice of law
Civil rights--United States

description: Family history and Southern tradition; legal practice; Reconstruction Finance Corporation; Government Reorganization Act; Defense Plant corporation; development programs; Federal Communications Commission; Communication Act of 1934; House Committee on Un-American Activities; FBI loyalty programs; broadcast license renewal considerations; academic freedom issue; Montgomery civil rights practice; impressions of Jesse Jones, Hugo Black, Aubrey Williams, others in New Deal Washington
Reminiscences of Clifford Roberts, 1972
Publisher: name: Columbia University
Year: 2020
Subjects: Investment bankers
Presidents--Election--1952.--United States
Presidents--Election--1956.--United States

description: Recollections of Dwight Eisenhower from 1948: hobbies, Presidency of Columbia University, North Atlantic Treaty Organization, 1952 and 1956 campaigns; Eisenhower's personal financial arrangements; Republican politics; impressions of Eisenhower's friends, family, aides, Cabinet; Eisenhower Citizens Committee; heart attack and ileitis operation; Augusta National Golf Club; impressions of W.A. (Pete) Jones and others
Massive Compact Halo Objects Viewed from a Cosmological Perspective: Contribution to the Baryonic Mass Density of the Universe
Creators: name: Fields, Brian D.
name: Freese, Katherine
name: Graff, David S.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: [Abridged] We estimate the contribution of Massive Compact Halo Objects (Machos) and their stellar progenitors to the mass density of the Universe. If the Machos that have been detected reside in the Halo of our Galaxy, then a simple extrapolation of the Galactic population (out to 50 kpc) of Machos to cosmic scales gives a cosmic density $ρ_{Macho} = (1-5) \times 10^9 h \msun \Mpc^{-3}$, which in terms of the critical density corresponds to $Ω_{Macho}=(0.0036-0.017) h^{-1}$. Such a mass density is comparable to the baryon density implied by Big Bang Nucleosynthesis. If we take the central values of the estimates, then Machos dominate the baryonic content of the Universe today, with $Ω_{Macho}/Ω_{Baryon} \sim 0.7 h$. However, the cumulative uncertainties in the density determinations only require that $Ω_{Macho}/Ω_{Baryon} \geq 1/6 h f_{gal}$, where the fraction of galaxies that contain Machos $f_{gal} > 0.17$, and $h$ is the Hubble constant in units of 100 km s$^{-1}$ Mpc$^{-1}$. Our best estimate for $Ω_{Macho}$ is hard to reconcile with the current best estimates of the baryonic content of the intergalactic medium indicated by measurements of the Lyman-$α$ forest. We explore the addition constraints that arise if the Machos are white dwarfs as suggested by the present microlensing data. We discuss the challenges this scenario presents at both the local and cosmic scales, emphasizing in particular the constraints on the required mass budget and nucleosynthesis products (particularly carbon).
description: 18 pages, LaTeX, uses AASTeX macros. In press, New Astronomy (submitted Jan. 20, 1998)
VALINCIS2 cruise,Téthys II R/V
Creators: name: TESSON Michel
name: LABAUNE Caroline
Publisher: name: Sismer
Year: 2006

description: Etude par sismique réflexion monotrace du système de vallées incisées quaternaires du Languedoc-Roussillon, Golfe du Lion, France. Le projet de rattachement est GDR "Marges".
The Evolution and Revival Structure of Localized Quantum Wave Packets
Creators: name: Bluhm, Robert
name: Kostelecky, Alan
name: Porter, James
Publisher: name: arXiv
Year: 1995
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Localized quantum wave packets can be produced in a variety of physical systems and are the subject of much current research in atomic, molecular, chemical, and condensed-matter physics. They are particularly well suited for studying the classical limit of a quantum-mechanical system. The motion of a localized quantum wave packet initially follows the corresponding classical motion. However, in most cases the quantum wave packet spreads and undergoes a series of collapses and revivals. We present a generic treatment of wave-packet evolution, and we provide conditions under which various types of revivals occur in ideal form. The discussion is at a level appropriate for an advanced undergraduate or first-year graduate course in quantum mechanics. Explicit examples of different types of revival structure are provided, and physical applications are discussed.
description: accepted for publication in Am. J. Phys
MPEC 2024-G109 : 2024 GQ1
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2024 GQ1

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Lubrication mechanisms of lipids and proteins in model synovial fluids
Creators: name: Parkes, Maria
Publisher: name: Imperial College London
Year: 2014

description: Artificial joints restore function which has been impaired due to disease, trauma or genetic conditions. Although many prostheses function satisfactorily for the lifetime of the patient, in some cases failure occurs due to wear of the bearing surfaces. To assess the wear life of artificial joint systems extensive testing in simulators is performed, yet there are discrepancies between the predicted performance and wear experienced in vivo. The lubricant used in simulators has a different chemical composition to synovial fluid. As the composition affects the performance of a lubricant, specifying a model fluid closer to synovial fluid will improve simulator testing, and consequently joint design. The difficulty in specifying a model fluid is that it is not fully understood which elements of synovial fluid determine the lubrication performance. This thesis aims to develop an understanding of how model synovial fluids can provide boundary lubrication in artificial joints. Static and dynamic measurements are used to reconcile the adsorption and lubrication behaviour of synovial fluid proteins and lipids. The boundary lubrication of both current prosthesis materials and cutting-edge artificial cartilage materials is considered. Static tests show changes to adsorbed films dependent on surface interactions, pH and interactions between proteins and lipids. This affects the hydration and macromolecular content of adsorbed layers, which impacts on the layer properties. Under loading and shear, pH and macromolecule interactions govern the formation of lubricating films, through both adsorption and the formation of thicker, aggregated films. Adsorbed film properties were strongly correlated with the lubricating film thickness for protein solutions, but affected by structural changes for solutions containing lipid vesicles. Comparing the lubrication of current and cutting-edge materials shows that the permeability of the surface influences the active lubrication mechanisms. Based on the findings of this work, recommendations for the composition of model synovial fluids are made.
Limit-Cycle Behaviour of Thermally-Unstable Accretion Flows onto Black Holes
Creators: name: Szuszkiewicz, Ewa
name: Miller, John C.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Nonlinear time-dependent calculations are being carried out in order to study the evolution of vertically-integrated models of non-selfgravitating, transonic accretion discs around black holes. In this paper we present results from a new calculation for a high-alpha model similar to one studied previously by Honma, Matsumoto and Kato who found evidence for limit-cycle behaviour connected with thermal instability. Our results are in substantial agreement with theirs but, in our calculation, the disc material does not always remain completely optically thick and we include a suitable treatment for this. We followed the evolution for several cycles and determined the period of the cycle as being about 780 seconds. Advective cooling is dominant in the region just behind the outward-moving peak of surface density. The behaviour of this model is significantly different from what we saw earlier for low-alpha models (which we discussed in a previous paper) and we contrast and compare the two situations.
description: 15 pages, 11 figures, to be published in MNRAS
Isolation and characterization of ent-pimarane diterpenoids from Sigesbeckia pubescens
Creators: name: Wang, Jianbin
name: Xie, Kehui
name: Wang, Qing
name: Li, Wenchao
name: Fu, Hongzheng
Publisher: name: Taylor & Francis
Year: 2019
Subjects: Biochemistry
Space Science
Medicine
Cell Biology
Pharmacology
Environmental Sciences not elsewhere classified
Chemical Sciences not elsewhere classified
Biological Sciences not elsewhere classified

description: Five new ent-pimarane diterpenoids ent-16-nor-2-oxopimar-8(14)-ene-15,19-dial (1), ent-16-nor-2α,19-dihydroxypimar-8-en-15-al (2), 3-O-acetyldarutigenol (3), 19-O-acetylkirenol (4), ent-16-nor-3β,15-dihydroxypimar-8(14)-ene (5) were isolated and characterized from the ethanol extract of Sigesbeckia pubescens. Their structures were elucidated on the basis of spectroscopic analysis. The absolute configuration of C-15 in compounds 3 and 4 was assigned using Snatzke’s method. All these compounds were assessed for their anti-inflammatory potential by measuring the inhibitory effects on NO production in LPS-induced RAW 264.7 macrophage cells and compound 4 showed significantly inhibitory activity with IC50 value of 5.9 μM.
Anisotropic Kondo pseudo-gap in URu2Si2
Creators: name: Buhot, J.
name: Montiel, X.
name: Gallais, Y.
name: Cazayous, M.
name: Sacuto, A.
name: Lapertot, G.
name: Aoki, D.
name: Hussey, N. E.
name: Pépin, C.
name: Burdin, S.
name: Méasson, M. -A.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: A polarized electronic Raman scattering study reveals the emergence of symmetry dependence in the electronic Raman response of single crystalline URu$_{2}$Si$_{2}$ below the Kondo crossover scale $T_K\sim100K$. In particular, the development of a coherent Kondo pseudo-gap predominantly in the E$_g$ channel highlights strong anisotropy in the Kondo physics in URu$_{2}$Si$_{2}$ that has previously been neglected in theoretical models of this system. A calculation of the Raman vertices demonstrates that the strongest Raman vertex does indeed develop within the E$_g$ channel for interband transitions and reaches a maximum along the diagonals of the Brillouin zone, implying a d-wave-like geometry for the Kondo pseudo-gap. Below the hidden order phase transition at $T_{HO}= 17.5K$, the magnitude of the pseudo-gap is found to be enhanced. Moreover, the anisotropy of the pseudo-gap is similar in form to that proposed for the chiral d-wave (E$_g$) superconducting state that appears below $T_c=1.5K$.
Macroporous polymer mixers
Creators: name: Tebboth, Michael Peter
Publisher: name: Imperial College London
Year: 2015

description: Macroporous polymers produced by polymerising the continuous phase of high (or medium) internal phase emulsions (H/MIPEs), commonly known as poly(merised)HIPEs (or polyMIPEs), have been intensively researched over the past two decades. The have been investigated for use in many diverse applications including chromatography, membranes, sorbtion, electrodes, bioengineering and filters amongst others. However this work investigates the use of their intricate internal pore structure for the mixing of fluids passing through polyHIPEs. When producing polyHIPEs (also polyMIPEs) by polymerisation of HIPE and MIPE templates it was found that the pore size could be controlled effectively by varying the energy used to agitate the emulsion template. The gas permeability of polyM/HIPEs increased linearly with increasing mean pore throat diameter for a given porosity. Through both residence time distribution experiments and examination of homogenous micromixing it was shown that the mixing in single-phase liquids increased when passed through a polyHIPE as the mean pore throat diameter decreases. There was no difference in mixing performance observed between polyHIPEs produced from Pickering emulsions compared to those produced from surfactant stabilised emulsions. By performing the liquid-liquid extraction of caffeine from aqueous solution with ethyl acetate within a polyHIPE flow cell it was shown that the overall mass transfer coefficient decreased with smaller mean pore throat diameters suggesting more effective mixing. The porosity of the polyHIPE monolith was not found to affect the overall mass transfer coefficient. It was possible to produce interfacial areas, up to 17,600 m2m-3, between the two immiscible liquid phases within polyHIPEs, comparable to industrial extraction methods such as mixer settlers. Impregnating the polyHIPE flow cells with palladium allowed examining whether it is possible to use them as three phase catalytic reactor for nitroreduction. The gas-liquid mixing within the reactor was found to be insufficient to prevent the reduction being mass transfer limited even in the reactors containing the smallest mean pore throat diameters. Less than 0.2% of the palladium catalyst within the reactor was lost from the polyHIPE pore structure during the nitroreductions reactions for all the polyHIPE reactors tested.
Acceleration of Quantum Fields
Creators: name: Jaekel, Marc-Thierry
name: Reynaud, Serge
Publisher: name: arXiv
Year: 1995
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We analyze the transformation of quantum fields under conformal coordinate transformations from inertial to accelerated frames, in the simple case of scalar massless fields in a two-dimensional spacetime, through the transformation of particle number and its spectral density. Particle number is found to be invariant under conformal coordinate transformations to uniformly accelerated frames, which extends the property already known for vacuum. Transformation of spectral density of particle number exhibits a redistribution of particles in the frequency spectrum. This redistribution is determined by derivatives of phase operators with respect to frequency, that is by time and position operators defined in such a manner that the redistribution of particles appears as a Doppler shift which depends on position in spacetime, in conformity with Einstein equivalence principle.
description: 16 pages, to appear in Brazilian Journal of Physics, special issue on Quantum Optics, ed. L. Davidovich
The relationship between aortic stiffness, health related quality of life and post-operative organs recovery (cardiac, renal and cognitive) following aortic valve replacement
Creators: name: Kidher, Emaddin
Publisher: name: Imperial College London
Year: 2014

description: Background: Aortic stiffness as measured by pulse wave velocity (PWV) is a predictor of cardiovascular disease and other outcomes in different diseased and healthy populations, independent of traditional risk factors. The relationships between PWV measurement, global functional outcome and injury to the brain, kidney, and heart have never been examined in cardiac surgery patients. Objective: The objective of this project was to assess the relationship between aortic stiffness and health related quality of life (QoL), cognitive function, acute kidney injury (AKI), and cardiac function in patients undergoing aortic valve replacement (AVR). Methods: Aortic PWV, QoL, cognitive function, left ventricular (LV) function and NYHA class were assessed pre- and post-operatively (409 ± 159 days). The brain injury biomarker, N-methyl-D-aspartate receptor antibody (NR2Ab), was measured pre-operatively only. The biomarker of myocardial strain, B-type natriuretic peptide (BNP), and the novel AKI biomarker, neutrophil gelatinase-associated lipocalin (NGAL), were measured pre-operatively, and at 3 h and 18-24 h post-CPB. Results: Fifty-six patients (16 females; mean age, 71 ± 8.4 years) were included in this study, of which 50 (89%) patients attended the follow-up visit. No relationship was found between the degree of aortic stenosis (AS) and PWV, and AVR had no effect on aortic stiffness post-operatively. QoL and NYHA class significantly improved, while cognitive function did not deteriorate after AVR. High PWV is independently related to poorer QoL, cognitive function levels and NYHA class both pre- and post-operatively. PWV was not related to LV function, BNP or NGAL levels, but it was independently related to the level of NR2Ab. PWV did not correlate with AKI which was developed in 30% of the cases. Early post-operative plasma level of NGAL is the earliest predictive marker of post-operative AKI and the need for early medical renal intervention. Pre-operative BNP level was significantly and negatively correlated with pre-operative LV function, AS (valve area), and NYHA class in the post-operative follow-up period. Conclusion: In AVR patients, PWV is independently related to global functional status, cognitive function and brain injury biomarkers, but is not related to AKI or myocardial strain.
Voluta ebraea Linnaeus, 1758, spec. nov.
Creators: name: Linnaeus, Carolus
Publisher: name: Laurentius Salvius
Year: 1758
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Neogastropoda
Volutidae
Voluta
Voluta ebraea

description: Voluta ebraea [spec. nov.]
V. testa fusiformi, anfractibus spinis subacutis, columella plicis quinque validioribus tribusque obsoletis.
Bonan. recr. 3. t. 293.
Rumph. mus. t. 32. f. I.
Gvalt. test. t. 28. f. I.
Argenv. conch. t. 17. f. D.
Habitat in O. Asiatico.
* * * * Ventricosae.
description: Published as part of Linnaeus, Carolus, 1758, Systema Naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Stockholm :Laurentius Salvius on page 733, DOI: 10.5962/bhl.title.542, http://zenodo.org/record/3922206
The Dispirited Case of Gauged $U(1)_{B-L}$ Dark Matter
Creators: name: Escudero, Miguel
name: Witte, Samuel J.
name: Rius, Nuria
Publisher: name: arXiv
Year: 2018
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We explore the constraints and phenomenology of possibly the simplest scenario that could account at the same time for the active neutrino masses and the dark matter in the Universe within a gauged $U(1)_{B-L}$ symmetry, namely right-handed neutrino dark matter. We find that null searches from lepton and hadron colliders require dark matter with a mass below 900 GeV to annihilate through a resonance. Additionally, the very strong constraints from high-energy dilepton searches fully exclude the model for $ 150 \, \text{GeV} < m_{Z'} < 3 \, \text{TeV}$. We further explore the phenomenology in the high mass region (i.e. masses $\gtrsim \mathcal{O}(1) \, \text{TeV}$) and highlight theoretical arguments, related to the appearance of a Landau pole or an instability of the scalar potential, disfavoring large portions of this parameter space. Collectively, these considerations illustrate that a minimal extension of the Standard Model via a local $U(1)_{B-L}$ symmetry with a viable thermal dark matter candidate is difficult to achieve without fine-tuning. We conclude by discussing possible extensions of the model that relieve tension with collider constraints by reducing the gauge coupling required to produce the correct relic abundance.
description: 21 pages, 8 figures. v2: References added. Matches the published version
Biophysical study of DNA at single molecule level using solid-state nanopores
Creators: name: Bahrami, Azadeh
Publisher: name: Imperial College London
Year: 2014

description: Since the discovery of deoxyribonucleic acid (DNA) over 140 years ago, this biomolecule still remains one the most studied macromolecules in nature. The modifications and interactions associated with this duplex biopolymer have been shown to play fundamental roles in cellular machinery. This research project exploited sets of single-molecule detection techniques in parallel with conventional molecular biology methodologies to study i) chemical modification (methylation) of the DNA and its functional role and ii) electrostatic interaction between two homologous DNA duplexes. In this project solid-state nanopores were utilised as a novel approach to probe structural and conformational changes of linear and circular DNA. To begin with, the effect of DNA methylation level in breast cancer cell-lines was investigated. Using solid-state nanopore sensors and a methyl specific antibody (5’-mc), the methylated and unmethylated regions of FOXA1 (a gene associated with breast cancer development) promoter were differentiated. Simultaneously, the methylation level of this gene was evaluated in various breast cancer cell-lines and confirmed the impact of DNA methylation in gene silencing. In addition, using atomic force microscopy analysis, the binding affinity of the antibody to the methylated DNA was determined Furthermore, by employing the same methodologies, the presence of an electrostatic recognition step in homologous segments of a bacteria plasmid within the framework of Kornyshev-Leikin theory was investigated. However to this end, the verification of this model was inconclusive. Nevertheless it was serendipitously found that the plasmid with homologous regions was dimerised and then formed a single loop. This finding would be the motivation behind further experiments to gain a better understanding of the possible sequence dependence of the DNA topology and configuration during cloning and amplification procedures. Furthermore, using a combination of various techniques, the biophysical properties of the monomeric and dimeric plasmids were characterised. Overall, the combined findings of the mentioned projects provided remarkable insights on the molecular biophysics of DNA-DNA and DNA-protein interactions within the framework of the central dogma of molecular biology.