cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Synchronization and enhanced catalysis of mechanically coupled enzymes
Creators: name: Agudo-Canalejo, Jaime
name: Adeleke-Larodo, Tunrayo
name: Illien, Pierre
name: Golestanian, Ramin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: We examine the stochastic dynamics of two enzymes that are mechanically coupled to each other, e.g., through an elastic substrate or a fluid medium. The enzymes undergo conformational changes during their catalytic cycle, which itself is driven by stochastic steps along a biased chemical free energy landscape. We find conditions under which the enzymes can synchronize their catalytic steps, and discover that the coupling can lead to a significant enhancement in their overall catalytic rate. Both effects can be understood as arising from a global bifurcation in the underlying dynamical system at sufficiently strong coupling. Our findings suggest that, despite their molecular scale, enzymes can be cooperative and improve their performance in metabolic clusters.
A balanced memory network
Creators: name: Roudi, Yasser
name: Latham, Peter E.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: A fundamental problem in neuroscience is understanding how working memory -- the ability to store information at intermediate timescales, like 10s of seconds -- is implemented in realistic neuronal networks. The most likely candidate mechanism is the attractor network, and a great deal of effort has gone toward investigating it theoretically. Yet, despite almost a quarter century of intense work, attractor networks are not fully understood. In particular, there are still two unanswered questions. First, how is it that attractor networks exhibit irregular firing, as is observed experimentally during working memory tasks? And second, how many memories can be stored under biologically realistic conditions? Here we answer both questions by studying an attractor neural network in which inhibition and excitation balance each other. Using mean field analysis, we derive a three-variable description of attractor networks. From this description it follows that irregular firing can exist only if the number of neurons involved in a memory is large. The same mean field analysis also shows that the number of memories that can be stored in a network scales with the number of excitatory connections, a result that has been suggested for simple models but never shown for realistic ones. Both of these predictions are verified using simulations with large networks of spiking neurons.
description: Accepted for publications in PLoS Comp. Biol
Additional file 2: of Alignment-free genome comparison enables accurate geographic sourcing of white oak DNA
Creators: name: Tang, Kujin
name: Ren, Jie
name: Cronn, Richard
name: Erickson, David
name: Milligan, Brook
name: Parker-Forney, Meaghan
name: Spouge, John
name: Sun, Fengzhu
Publisher: name: figshare
Year: 2018
Subjects: subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Evolutionary Biology
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: Marine Biology
subject: Cancer
subject: Plant Biology
subject: Virology
subject: Computational Biology

description: Figure S3. The relationship between the first three principal coordinates and (A) longitude and (B) latitude of the tree samples based on the d 2 â $$ {d}_2^{\ast } $$ dissimilarity values using sequencing quantity of 100 Mbp. The k-mer length is 12 and the Markov order of the background sequence is 10. The first principal coordinate separates the North America tree samples from the Europe and Asia tree samples, and the third principal coordinate separates the Europe samples from Asia samples. The second principal coordinates of most Asian samples are larger than that of the Europe samples. However, the second principal coordinate does not separate them. (PDF 68 kb)
The Tarantula Massive Binary Monitoring V. R 144: a wind-eclipsing binary with a total mass > 140 Msun
Creators: name: Shenar, T.
name: Sana, H.
name: Marchant, P.
name: Pablo, B.
name: Richardson, N.
name: Moffat, A. F. J.
name: Van Reeth, T.
name: Barba, R. H.
name: Bowman, D. M.
name: Broos, P.
name: Crowther, P. A.
name: Clark, J. S.
name: de Koter, A.
name: de Mink, S. E.
name: Dsilva, K.
name: Graefener, G.
name: Howarth, I. D.
name: Langer, N.
name: Mahy, L.
name: Apellaniz, J. Maiz
name: Pollock, A. M. T.
name: Schneider, F. R. N.
name: Townsley, L.
name: Vink, J. S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: R 144 is the visually brightest WR star in the Large Magellanic Cloud (LMC). R 144 was reported to be a binary, making it potentially the most massive binary thus observed. We perform a comprehensive spectral, photometric, orbital, and polarimetric analysis of R 144. R 144 is an eccentric (e=0.51) 74.2-d binary comprising two relatively evolved (age~2 Myr), H-rich WR stars. The hotter primary (WN5/6h, T=50 kK) and the cooler secondary (WN6/7h,T=45kK) have nearly equal masses. The combination of low rotation and H-depletion observed in the system is well reproduced by contemporary evolution models that include boosted mass-loss at the upper-mass end. The systemic velocity of R 144 and its relative isolation suggest that it was ejected as a runaway from the neighbouring R 136 cluster. The optical light-curve shows a clear orbital modulation that can be well explained as a combination of two processes: excess emission stemming from wind-wind collisions and double wind eclipses. Our light-curve model implies an orbital inclination of i=60.4+-1.5deg, resulting in accurately constrained dynamical masses of 74+-4 and 69+-4 Msun. Assuming that both binary components are core H-burning, these masses are difficult to reconcile with the derived luminosities (logL1,2 = 6.44, 6.39 [Lsun]), which correspond to evolutionary masses of the order of 110 and 100Msun, respectively. Taken at face value, our results imply that both stars have high classical Eddington factors of Gamma_e = 0.78+-0.1. If the stars are on the main sequence, their derived radii (~25Rsun) suggest that they are only slightly inflated, even at this high Eddington factor. Alternatively, the stars could be core-He burning, strongly inflated from the regular size of classical Wolf-Rayet stars (~1Rsun), a scenario that could help resolve the observed mass discrepancy.
description: Accepted to A&A on the April 06 2021. 17 pages + 5 page appendix. Version 28.10.2021: corrected typo in Eq. (2); numerator and denominator were inversed on RHS (only typo; no impact on results)
Quantized symplectic actions and W-algebras
Creators: name: Losev, Ivan
Publisher: name: arXiv
Year: 2007
Subjects: subject: Representation Theory (math.RT)
subject: Quantum Algebra (math.QA)
subject: Symplectic Geometry (math.SG)
subject: FOS: Mathematics
subject: 17B35, 53D55

description: With a nilpotent element in a semisimple Lie algebra g one associates a finitely generated associative algebra W called a W-algebra of finite type. This algebra is obtained from the universal enveloping algebra U(g) by a certain Hamiltonian reduction. We observe that W is the invariant algebra for an action of a reductive group G with Lie algebra g on a quantized symplectic affine variety and use this observation to study W. Our results include an alternative definition of W, a relation between the sets of prime ideals of W and of the corresponding universal enveloping algebra, the existence of a one-dimensional representation of W in the case of classical g and the separation of elements of W by finite dimensional representations.
description: v1 21 pages, v2 Hamiltonian actions are no longer used whence the change of title. Proofs of Theorem 1.2.2(iii),(vi) and Theorem 1.2.3(ii) were modified. v3 a mistake in the statement of Theorem 1.2.2(ix) was fixed v.4 substancial changes, proof of Theorem 1.2.3(i) rewritten, v.5 final version to appear in JAMS
The Written British National Corpus 2014: Design, Compilation and Analysis
Creators: name: Hawtin, Abigail
Publisher: name: Lancaster University
Year: 2019
Subjects: Corpus
British National Corpus
Design
Compilation
Colloquialisation
Representativeness

description: The ESRC-funded Centre for Corpus Approaches to Social Science at
      Lancaster University (CASS) and the English Language Teaching Group at
      Cambridge University Press (CUP) have collaborated to compile a new,
      publicly accessible corpus of contemporary Written British English, known
      as the Written British National Corpus 2014 (Written BNC2014). The Written
      BNC2014 is an updated version of the Written British National Corpus
      (Written BNC1994) which was created in the 1990s. The Written BNC1994 is
      often used as a proxy for present day British English, so the Written
      BNC2014 has been created in order to allow for both comparisons between
      the two corpora, and also to allow for research on British English to be
      carried out using a state-of-the-art contemporary data-set. The Written
      BNC2014 contains approximately 90 million words of written British
      English, published between 2010-2018, from a wide variety of genres. The
      corpus will be publicly released in 2019.

      This thesis presents a detailed account of the design and compilation of
      the corpus, focusing on the very many challenges which needed to be
      overcome in order to create the corpus, along with the solutions to these
      challenges which were devised. It also demonstrates the utility of the
      corpus, by presenting a diachronic comparison of academic writing in the
      1990s and 2010s, with a focus on the theory of colloquialisation.

      This thesis, whilst not a Written BNC2014 user-guide, presents all of the
      decisions made in the design and creation of the corpus, and as such, will
      help to make the corpus as useful to as many people, for as many purposes,
      as possible.
Transposition of Tn916 in the four replicons of the Butyrivibrio proteoclasticus B316T genome
Creators: name: Cookson, Adrian
name: Noel, Samantha
name: Hussein, Hassan
name: Perry, Rechelle
name: Sang, Carrie
name: Moon, Christina
name: Leahy, Sinead
name: Altermann, Eric
name: Kelly, Bill
name: Attwood, Graeme
Publisher: name: AgResearch
Year: 2024
Subjects: classificationCode: 3107
subject: Microbiology
subject: FOS: Biological sciences

description: The rumen bacterium Butyrivibrio proteoclasticus B316T has a 4.4-Mb genome composed of four replicons (approximately 3.55Mb, 361, 302 and 186kb). Mutagenesis of B316T was performed with the broad host-range conjugative transposon Tn916 to screen for functionally important characteristics. The insertion sites of 123 mutants containing a single copy of Tn916 were identified and corresponded to 53 different insertion points, of which 18 (34.0%), representing 39 mutants (31.7%), were in ORFs and 12 were where transposition occurred in both directions (top and bottom DNA strand). Up to eight mutants from several independent conjugation experiments were found to have the same integration site. Although transposition occurred in all four replicons, the number of specific insertion sites, transposition frequency and the average intertransposon distance between insertions varied between the four replicons. In silico analysis of the 53 insertion sites was used to model a target consensus sequence for Tn916 integration into B316T. A search of the B316T genome using the modelled target consensus sequence (up to two mismatches) identified 39 theoretical Tn916 insertion sites (19 coding, 20 noncoding), of which nine corresponded to Tn916 insertions identified in B316T mutants during our conjugation experiments.
Circumcentering approximate reflections for solving the convex feasibility problem
Creators: name: Araújo, Guilherme
name: Arefidamghani, Reza
name: Behling, Roger
name: Bello-Cruz, Yunier
name: Iusem, Alfredo
name: Santos, Luiz-Rafael
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 49M27 65K05 65B99 90C25

description: The circumcentered-reflection method (CRM) has been applied for solving convex feasibility problems. CRM iterates by computing a circumcenter upon a composition of reflections with respect to convex sets. Since reflections are based on exact projections, their computation might be costly. In this regard, we introduce the circumcentered approximate-reflection method (CARM), whose reflections rely on outer-approximate projections. The appeal of CARM is that, in rather general situations, the approximate projections we employ are available under low computational cost. We derive convergence of CARM and linear convergence under an error bound condition. We also present successful theoretical and numerical comparisons of CARM to the original CRM, to the classical method of alternating projections (MAP) and to a correspondent outer-approximate version of MAP, referred to as MAAP. Along with our results and numerical experiments, we present a couple of illustrative examples.
Dynamic Boundaries of Event Horizon Magnetospheres
Creators: name: Punsly, Brian
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: This Letter analyzes 3-dimensional simulations of Kerr black hole magnetospheres that obey the general relativistic equations of perfect magnetohydrodynamics (MHD). Particular emphasis is on the event horizon magnetosphere (EHM) which is defined as the the large scale poloidal magnetic flux that threads the event horizon of a black hole (This is distinct from the poloidal magnetic flux that threads the equatorial plane of the ergosphere, which forms the ergospheric disk magnetosphere). Standard MHD theoretical treatments of Poynting jets in the EHM are predicated on the assumption that the plasma comprising the boundaries of the EHM plays no role in producing the Poynting flux. The energy flux is electrodynamic in origin and it is essentially conserved from the horizon to infinity, this is known as the Blandford-Znajek (B-Z) mechanism. To the contrary, within the 3-D simulations, the lateral boundaries are strong pistons for MHD waves and actually inject prodigious quantities of Poynting flux into the EHM. At high black hole spin rates, strong sources of Poynting flux adjacent to the EHM from the ergospheric disk will actually diffuse to higher latitudes and swamp any putative B-Z effects. This is in contrast to lower spin rates, which are characterized by much lower output powers and modest amounts of Poynting flux are injected into the EHM from the accretion disk corona.
description: To appear in MNRAS Letters. A high resolution version can be found at: http://85.20.11.14/hosting/punsly/MNRAS%20Letter7.20.07/
Slowly migrating tectonic microearthquake swarms in the Icelandic Rift Zone: driven by pore-pressure or aseismic slip transients?
Creators: name: Winder, Tom
name: White, Robert S
Publisher: name: Copernicus GmbH
Year: 2022

description:
Intense swarms of microearthquakes have been detected in the rift zone of Central Iceland since the 1970s, but the cause of their clear swarm-like nature remains enigmatic. We use the QuakeMigrate earthquake detection and location software1 to produce a highly complete catalogue of microseismicity from 2007-2020, using data from a dense local seismic network. Automatic hypocentre locations have been refined using waveform cross-correlation and double-difference relocation, and tightly constrained focal mechanisms have been obtained by manual analysis of a subset of events.

The resulting high-resolution earthquake catalogue reveals a network of conjugate strike-slip faults, oriented to accommodate plate-boundary extension. Sharply defined fault planes imaged by the microearthquake hypocentres range from 1-10 km in length, and are found between 1 and 8 km b.s.l., with their orientations closely matching the fault plane geometry inferred from the fault plane solutions. Seismicity within individual swarms displays a systematic migration of hypocentres at velocities of ~ 1 km/day. In the majority of swarms we also observe clusters of identical repeating events, providing evidence for re-loading of brittle asperities.

For a selection of swarms our high resolution seismic observations are complemented by GPS and InSAR measurements, allowing us to place constraints on the amount of fault slip. Comparing this, and the area of the fault plane activated in the swarm, to the seismic moment release reveals a significant contribution of aseismic slip, or very low effective stress drop. Analysis of swarms within this fault network triggered by the 2014 B&#225;r&#240;arbunga-Holuhraun dike intrusion provides further constraint on the amplitude of the stress cycle.

We combine our observations with comparisons to numerical & laboratory modelling studies, observed swarm scaling properties and knowledge of the geological and permeability structure of the Icelandic crust to determine the nature of the transient forcing driving these exceptionally well-recorded tectonic earthquake swarms.

&#160;

1: https://github.com/QuakeMigrate/QuakeMigrate Tom Winder, Conor Bacon, Jonathan D. Smith, Thomas S. Hudson, Julian Drew, & Robert S. White. (2021, January 15). QuakeMigrate v1.0.0 (Version v1.0.0). Zenodo. http://doi.org/10.5281/zenodo.4442749
Analytic and exponentially localized brane-world Reissner-Nordström-AdS solution: a top-down approach
Creators: name: Nakas, Theodoros
name: Kanti, Panagiota
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this work, we construct a five-dimensional spherically-symmetric, charged and asymptotically Anti-de Sitter black hole with its singularity being point-like and strictly localised on our brane. In addition, the induced brane geometry is described by a Reissner-Nordström-(A)dS line-element. We perform a careful classification of the horizons, and demonstrate that all of them are exponentially localised close to the brane thus exhibiting a pancake shape. The bulk gravitational background is everywhere regular, and reduces to an AdS$_5$ spacetime right outside the black-hole event horizon. This geometry is supported by an anisotropic fluid with only two independent components, the energy density $ρ_E$ and tangential pressure $p_2$. All energy conditions are respected close to and on our brane, but a local violation takes place within the event horizon regime in the bulk. A tensor-vector-scalar field-theory model is built in an attempt to realise the necessary bulk matter, however, in order to do so, both gauge and scalar degrees of freedom need to turn phantom-like at the bulk boundary. The study of the junction conditions reveals that no additional matter needs to be introduced on the brane for its consistent embedding in the bulk geometry apart from its constant, positive tension. We finally compute the effective gravitational equations on the brane, and demonstrate that the Reissner-Nordström-(A)dS geometry on our brane is caused by the combined effect of the five-dimensional geometry and bulk matter with its charge being in fact a tidal charge.
description: 25 pages, 6 figures, analysis extended, references updated, matches published version
The effect of electrolytic lesion and neural implants on glial fibrillary acidic protein expression in the rat spinal cord
Creators: name: Falconer, Robert J.
Publisher: name: University of British Columbia
Year: 2010

description: This thesis assessed the suitability of unilateral, electrolytic lesions as a model of spinal cord damage and repair in the adult rat. This type of lesion resulted acutely in localized damage in the upper motor neuron at the L2-L3 level of the spinal cord. Minimal acute damage to ascending sensory pathways was indicated by preserved somatosensory evoked potentials elicited by stimulation of the tibial nerve. Immediately after lesion generation one of several substrates was injected into the lesion cavity. These substrates were saline buffer, liquid collagen solution, foetal spinal cord cells from 14 day old rat embryos, and a mixture of collagen and E 14 foetal spinal cord cells. The 4 groups were compared for functional recovery over 3 months using the inclined plane test and a Tarlov movement scale. After sacrifice, the tibialis anterior muscles were dissected and weighed to assess atrophy due to lower motor neuron injury. After removing and embedding the spinal cords in paraffin, transverse and longitudinal sections were taken for cytoarchitectural investigation. Cresyl violet was used to indicate Nissl substance, Luxol fast blue stained for myelin and anti - glial fibrillary acidic protein (GFAP) antibody revealed the expression of GFAP in the cord sections. Chronic electrolytic lesions were characterized by the highly variable degree of cavitation, demyelination and macrophage infiltration that was present. There was no significant performance deficit on the inclined plane test in any of the lesioned groups when compared to unoperated animals. The tibialis muscles from all groups were of normal weight, indicating that the lower motor neurons were not significantly damaged by the lesions used. There was, however, a marked decrease in the number of GFAP reactive astrocytes in the lesioned animals when compared to unlesioned controls (P < 0.01, Wilcoxon test). Moreover, this reduction of GFAP - like immunoreactivity was not prevented by implants of foetal neurons, collagen or foetal neurons suspended in collagen. Possible explanations for the reduced GFAP - like immunoreactivity seen in all electrolytically lesioned cords are discussed.
A Photoevaporating Rotating Disk in the Cepheus A HW2 Star Cluster
Creators: name: Jimenez-Serra, I.
name: Martin-Pintado, J.
name: Rodriguez-Franco, A.
name: Chandler, C.
name: Comito, C.
name: Schilke, P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present VLA and PdBI subarcsecond images (0.15"-0.6") of the radiocontinuum emission at 7 mm and of the SO2 J=19_{2,18}-18_{3,15} and J=27_{8,20}-28_{7,21} lines toward the Cepheus A HW2 region. The SO2 images reveal the presence of a hot core internally heated by an intermediate mass protostar, and a circumstellar rotating disk around the HW2 radio jet with size 600AUx100AU and mass of 1M_sun. Keplerian rotation for the disk velocity gradient of 5 kms-1 requires a 9 M_sun central star, which cannot explain the total luminosity observed in the region. This may indicate that the disk does not rotate with a Keplerian law due to the extreme youth of this object. Our high sensitivity radiocontinuum image at 7 mm shows in addition to the ionized jet, an extended emission to the west (and marginally to the south) of the HW2 jet, filling the south-west cavity of the HW2 disk. From the morphology and location of this free-free continuum emission at centimeter and millimeter wavelengths (spectral index of 0.4-1.5), we propose that the disk is photoevaporating due to the UV radiation from the central star. All this indicates that the Cepheus A HW2 region harbors a cluster of massive stars. Disk accretion seems to be the most plausible way to form massive stars in moderate density/luminosity clusters.
description: 4 pages, 2 figures, accepted for publication in ApJL
Wide-orbit exoplanets are common. Analysis of nearly 20 years of OGLE microlensing survey data
Creators: name: Poleski, R.
name: Skowron, J.
name: Mróz, P.
name: Udalski, A.
name: Szymański, M. K.
name: Pietrukowicz, P.
name: Ulaczyk, K.
name: Rybicki, K.
name: Iwanek, P.
name: Wrona, M.
name: Gromadzki, M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We use nearly 20 years of photometry obtained by the OGLE survey to measure the occurrence rate of wide-orbit (or ice giant) microlensing planets, i.e., with separations from ~5 AU to ~15 AU and mass-ratios from $10^{-4}$ to 0.033. In a sample of 3112 events we find six previously known wide-orbit planets and a new microlensing planet or brown dwarf OGLE-2017-BLG-0114Lb, for which close and wide orbits are possible and close orbit is preferred. We run extensive simulations of the planet detection efficiency, robustly taking into account the finite-source effects. We find that the extrapolation of the previously measured rate of microlensing planets significantly underpredicts the number of wide-orbit planets. On average, every microlensing star hosts $1.4^{+0.9}_{-0.6}$ ice giant planets.
description: 8 figures, anciliary files attached
Wetting Properties of Grain Boundaries in Solid Helium 4
Creators: name: Sasaki, S.
name: Caupin, F.
name: Balibar, S.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We have observed boundaries between hcp $^4$He crystal grains in equilibrium with liquid $^4$He. We have found that, when emerging at the liquid-solid interface, a grain boundary makes a groove whose dihedral angle $2θ$ is non-zero. This measurement shows that grain boundaries are not completely wet by the liquid phase, in agreement with recent Monte Carlo simulations. Depending on the value of $θ$, the contact line of a grain boundary with a solid wall may be wet by the liquid. In this case, the line is a thin channel with a curved triangular cross section, whose measured width agrees with predictions from a simple model. We discuss these measurements in the context of grain boundary premelting and for a future understanding of the possible supersolidity of solid $^4$He.
description: 4 pages, 4 figures
Nonperturbative resonant strong field ionization of atomic hydrogen
Creators: name: Girju, M. G.
name: Hristov, K.
name: Kidun, O.
name: Bauer, D.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We investigate resonant strong field ionization of atomic hydrogen with respect to the 1s-2p-transition. By "strong" we understand that Rabi-periods are executed on a femtosecond time scale. Ionization and AC Stark shifts modify the bound state dynamics severely, leading to nonperturbative signatures in the photoelectron spectra. We introduce an analytical model, capable of predicting qualitative features in the photoelectron spectra such as the positions of the Autler-Townes peaks for modest field strengths. Ab initio solutions of the time-dependent Schroedinger equation show a pronounced shift and broadening of the left Autler-Townes peak as the field strength is increased. The right peak remains rather narrow and shifts less. This result is analyzed and explained with the help of exact AC Stark shifts and ionization rates obtained from Floquet theory. Finally, it is demonstrated that in the case of finite pulses as short as 20fs the Autler-Townes duplet can still be resolved. The fourth generation light sources under construction worldwide will provide bright, coherent radiation with photon energies ranging from a tenth of a meV up to tens of keV, hence covering the regime studied in the paper so that measurements of nonperturbative, relative AC Stark shifts should become feasible with these new light sources.
description: 16 pages, 11 figures, IOP style
Shocks and Information Exchange in de Sitter Space
Creators: name: Aalsma, Lars
name: Cole, Alex
name: Morvan, Edward
name: van der Schaar, Jan Pieter
name: Shiu, Gary
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We discuss some implications of recent progress in understanding the black hole information paradox for complementarity in de Sitter space. Extending recent work by two of the authors, we describe a bulk procedure that allows information expelled through the cosmological horizon to be received by an antipodal observer. Generically, this information transfer takes a scrambling time $t = H^{-1}\log(S_{\rm dS})$. We emphasize that this procedure relies crucially on selection of the Bunch-Davies vacuum state, interpreted as the thermofield double state that maximally entangles two antipodal static patches. The procedure also requires the presence of an (entangled) energy reservoir, created by the collection of Hawking modes from the cosmological horizon. We show how this procedure avoids a cloning paradox and comment on its implications.
description: 21 pages + appendix. v2: added references, minor clarifications. v3: matches published version
Gravitational waves from galaxy encounters
Creators: name: Quilis, V.
name: González-García, A. C.
name: Sáez, D.
name: Font, J. A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We discuss the emission of gravitational radiation produced in encounters of dark matter galactic halos. To this aim we perform a number of numerical simulations of typical galaxy mergers, computing the associated gravitational radiation waveforms as well as the energy released in the processes. Our simulations yield dimensionless gravitational wave amplitudes of the order of $10^{-13}$ and gravitational wave frequencies of the order of $10^{-16}$ Hz, when the galaxies are located at a distance of 10 Mpc. These values are of the same order as those arising in the gravitational radiation originated by strong variations of the gravitational field in the early Universe, and therefore, such gravitational waves cannot be directly observed by ground-based detectors. We discuss the feasibility of an indirect detection by means of the B-mode polarization of the Cosmic Microwave Background (CMB) induced by such waves. Our results show that the gravitational waves from encounters of dark matter galactic halos leave much too small an imprint on the CMB polarization to be actually observed with ongoing and future missions.
description: 9 pages with revtex style, 3 ps figures; to be published in Physical Review D
Harnessing superdirectivity in dielectric spherical multilayer antennas
Creators: name: Gaponenko, Roman
name: Moroz, Alexander
name: Rasskazov, Ilia L.
name: Ladutenko, Konstantin
name: Shcherbakov, Alexey
name: Belov, Pavel
Publisher: name: arXiv
Year: 2021
Subjects: subject: Applied Physics (physics.app-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Small form-factor, narrowband, and highly directive antennas are of critical importance in a variety of applications spanning wireless communications, remote sensing, Raman spectroscopy, and single photon emission enhancement. Surprisingly, we show that the classical directivity limit can be appreciably surpassed for electrically small multilayer spherical antennas excited by a point electric dipole even if limiting ourselves to purely dielectric materials. Experimentally feasible designs of superdirective antennas are established by using a stochastic optimization algorithm combined with a rigorous analytic solution.
Ground-state magneto-optical resonances in Cesium vapour confined in an extremely thin cell
Creators: name: Andreeva, C.
name: Atvars, A.
name: Auzinsh, M.
name: Bluss, K.
name: Cartaleva, S.
name: Petrov, L.
name: Slavov, D.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Experimental and theoretical studies are presented related to the ground-state magneto-optical resonance prepared in Cesium vapour confined in an Extremely Thin Cell (ETC, with thickness equal to the wavelength of the irradiating light). It is shown that the utilization of the ETC allows one to examine the formation of a magneto-optical resonance on the individual hyperfine transitions, thus distinguishing processes resulting in dark (reduced absorption) or bright (enhanced absorption) resonance formation. We report on an experimental evidence of the bright magneto-optical resonance sign reversal in Cs atoms confined in the ETC. A theoretical model is proposed based on the optical Bloch equations that involves the elastic interaction processes of atoms in the ETC with its walls resulting in depolarization of the Cs excited state which is polarized by the exciting radiation. This depolarization leads to the sign reversal of the bright resonance. Using the proposed model, the magneto-optical resonance amplitude and width as a function of laser power are calculated and compared with the experimental ones. The numerical results are in good agreement with the experiment.
Excitons in Silicon Nanocrystalites: The Nature of Luminescence
Creators: name: Luppi, Eleonora
name: Iori, Federico
name: Magri, Rita
name: Pulci, Olivia
name: Ossicini, Stefano
name: Degoli, Elena
name: Olevano, Valerio
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: The absorption and emission spectra of silicon nanocrystals up to 1 nm diameter including geometry optimization and the many-body effects induced by the creation of an electron-hole pair have been calculated within a first-principles framework. Starting from hydrogenated silicon clusters of different size, different Si/O bonding at the cluster surface have been considered. We found that the presence of a Si-O-Si bridge bond originates significative excitonic luminescence features in the visible range that are in fair agreement with the experimental outcomes.
description: 12 pages 4 figures
Considering the Case for Biodiversity Cycles: Reexamining the Evidence for Periodicity in the Fossil Record
Creators: name: Lieberman, Bruce S.
name: Melott, Adrian L.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: Astrophysics (astro-ph)
subject: Geophysics (physics.geo-ph)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: Medvedev and Melott (2007) have suggested that periodicity in fossil biodiversity may be induced by cosmic rays which vary as the Solar System oscillates normal to the galactic disk. We re-examine the evidence for a 62 million year (Myr) periodicity in biodiversity throughout the Phanerozoic history of animal life reported by Rohde & Mueller (2005), as well as related questions of periodicity in origination and extinction. We find that the signal is robust against variations in methods of analysis, and is based on fluctuations in the Paleozoic and a substantial part of the Mesozoic. Examination of origination and extinction is somewhat ambiguous, with results depending upon procedure. Origination and extinction intensity as defined by RM may be affected by an artifact at 27 Myr in the duration of stratigraphic intervals. Nevertheless, when a procedure free of this artifact is implemented, the 27 Myr periodicity appears in origination, suggesting that the artifact may ultimately be based on a signal in the data. A 62 Myr feature appears in extinction, when this same procedure is used. We conclude that evidence for a periodicity at 62 Myr is robust, and evidence for periodicity at approximately 27 Myr is also present, albeit more ambiguous.
description: Minor modifications to reflect final published version
Additional file 7: of Alignment-free genome comparison enables accurate geographic sourcing of white oak DNA
Creators: name: Tang, Kujin
name: Ren, Jie
name: Cronn, Richard
name: Erickson, David
name: Milligan, Brook
name: Parker-Forney, Meaghan
name: Spouge, John
name: Sun, Fengzhu
Publisher: name: figshare
Year: 2018
Subjects: subject: Space Science
subject: Microbiology
subject: FOS: Biological sciences
subject: Genetics
subject: Molecular Biology
subject: Sociology
subject: FOS: Sociology
subject: Biological Sciences not elsewhere classified
subject: Information Systems not elsewhere classified

description: Table S1. Library construction, sequencing, and genome enrichment methods used for all DNA libraries in this study. (PDF 29 kb)
On the possibility of extending the Nore-Frenkel generalized law of correspondent states to non-isotropic patchy interactions
Creators: name: Foffi, Giuseppe
name: Sciortino, Francesco
Publisher: name: arXiv
Year: 2007
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Colloidal systems (and protein solutions) are often characterized by attractive interactions whose range is much smaller than the particle size. When this is the case and the interaction is spherical, systems obey a generalized law of correspondent states (GLCS), first proposed by Noro and Frenkel [ J.Chem.Phys. 113, 2941 (2000) ]. The thermodynamic properties become insensitive to the details of the potential, depending only on the value of the second virial coefficient B_2 and the density $ρ$. The GLCS does not generically hold for the case of non-spherical potentials. In this Letter we suggest that when particles interact via short-ranged small-angular amplitude patchy interactions (so that the condition of only one bond per patch is fulfilled) it is still possible to generalize the GLCS close to the liquid-gas critical point. Keywords: Colloids, Second Virial Coefficient, Proteins interactions, Short-ranged attractive attractions.
description: 11 pages, 3 figures. Accepted for publication on J. Phys. Chem. B
Young infants demonstrate a preference for infant directed talk
Creators: name: Pegg, Judith E.
Publisher: name: University of British Columbia
Year: 2010

description: This research was designed to assess 7-week-old infants' preference for infant directed and adult directed talk. (IDT and ADT) using the infant controlled habituation/dishabituation looking procedure. Infants were presented with short audio recordings of either a female or a male speaking in IDT during habituation and ADT during dishabituation or the reverse. In the control conditions, the stimulus did not change. Infants demonstrated preference for IDT over ADT in both male and female speaker conditions. They also demonstrated preference for the female speaker used in this study over the male speaker. Interactions among the dependent variables (first three looks), and the independent variables (infant gender, and style of speaking as well as infant gender, and speaker gender), suggest that the preference might not be as robust as the preference found in infants over 4 months. Evidence for discrimination between IDT and ADT was inferred from the between group demonstration of preference, but no evidence of within infant discrimination was found. Because the evidence suggests that 7-week-old infants demonstrate weaker preference for IDT over ADT than do infants of 4 months, it is assumed that infant preferences follow a developmental sequence. Thus, it is possible that developing preferences are influenced by experiential factors.
title: De la migration aux épreuves
title: De la migration aux épreuves
titleType: AlternativeTitle
Creators: name: Cudré-Mauroux, Estelle
Publisher: name: Unknown
Year: 0
Subjects: subject: Épreuves
subject: Insertion sociale/ scolaire
subject: Intégration
subject: Écoles
subject: Relation école-famille
subject: Ressources

description: Dans le cadre de cadre de cette recherche, je me suis intéressée au vécu des personnes qui ont immigré. Pour ce faire, j’ai choisi d’utiliser une méthode de type exploratoire et qualitative afin de tendre vers une analyse fine. C’est ainsi que j’ai utilisé la méthode de la théorie fondée qui permet d’étudier des phénomènes sociaux à partir des données du terrain. De ce fait, le cadre conceptuel n’a jamais été figé et s’est composé de différents concepts en sociologie tels que : l’épreuve, les différents modèles d’intégration et la relation école-famille. La première thématique traitée m’a amené à effectuer ma propre conceptualisation de l’épreuve. En effet, c’est grâce à cette représentation que j’ai pu percevoir certains obstacles rencontrés par les individus. La deuxième thématique permet de mieux comprendre les différents processus d’intégration lors de l’arrivée dans un pays d’accueil. Ainsi, lors de l’analyse, j’ai pu identifier certaines influences des processus d’intégration. Puis la dernière thématique étudiée m’a aidé à la compréhension de l’interaction entre l’école et la famille et des possibles inégalités auxquelles les foyers peuvent être confrontés. À travers cette étude, j’ai donc souhaité identifier les potentielles épreuves vécues par les immigrés lors d’une insertion sociale et scolaire. Pour ce faire, des entretiens compréhensifs ont été effectués avec un échantillon de 8 personnes ayant vécu une migration. Puis grâce une analyse détaillée quatre épreuves ont été identifiées ; l’épreuve du sans-papier, l’épreuve de l’apprentissage de la langue, l’épreuve de l’entrée dans le système scolaire et l’épreuve de la différence. Chacune a été explicitée selon ses composantes, ses conséquences sur l’individu et les ressources mobilisées. Ces différentes épreuves sont vécues de manière individuelle, certaines pouvant être plus éprouvantes que d’autres. De plus, il serait possible d’imaginer qu’il existerait une épreuve plus générale de la migration qui se composerait des épreuves que j’ai identifiées.
Additional file 1: of The relationship between latex metabolism gene expression with rubber yield and related traits in Hevea brasiliensis
Creators: name: Wu, Chuntai
name: Lan, Li
name: Li, Yu
name: Nie, Zhiyi
name: Zeng, Rizhong
Publisher: name: figshare
Year: 2018
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Physiology
subject: Pharmacology
subject: Ecology
subject: Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Marine Biology
subject: Hematology
subject: Virology
subject: Computational Biology

description: Table S1. Primers designed from EST sequences for RT-qPCR analysis of rubber synthetic and latex metabolic genes and their reference gene. (DOC 33 kb)
Additional file 2: of The relationship between latex metabolism gene expression with rubber yield and related traits in Hevea brasiliensis
Creators: name: Wu, Chuntai
name: Lan, Li
name: Li, Yu
name: Nie, Zhiyi
name: Zeng, Rizhong
Publisher: name: figshare
Year: 2018
Subjects: subject: Cell Biology
subject: Molecular Biology
subject: Environmental Sciences not elsewhere classified
subject: Ecology
subject: FOS: Biological sciences
subject: Biological Sciences not elsewhere classified
subject: Plant Biology
subject: Virology
subject: Computational Biology

description: Table S2. Change analysis of monthly mean latex yield per tapping and annual latex yield from single plant of different cultivars. (DOC 34 kb)
Many-Body Physics with Ultracold Gases
Creators: name: Bloch, Immanuel
name: Dalibard, Jean
name: Zwerger, Wilhelm
Publisher: name: arXiv
Year: 2007
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: This article reviews recent experimental and theoretical progress on many-body phenomena in dilute, ultracold gases. Its focus are effects beyond standard weak-coupling descriptions, like the Mott-Hubbard-transition in optical lattices, strongly interacting gases in one and two dimensions or lowest Landau level physics in quasi two-dimensional gases in fast rotation. Strong correlations in fermionic gases are discussed in optical lattices or near Feshbach resonances in the BCS-BEC crossover.
description: revised version, accepted for publication in Rev. Mod. Phys
On the Universal Tachyon and Geometrical Tachyon
Creators: name: Kluson, J.
name: Panigrahi, Kamal L.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study properties of non-BPS D(p+1)-brane in the background of k NS5-branes, with one transverse direction compactified on a circle, from the point of view of Dirac-Born-Infeld action. We present the analysis of two different embedding of non-BPS D(p+1)-brane in given background and study the classical solutions of given world-volume theory. We argue for the configuration of a non-BPS D(p+1)-brane which allows us to find solutions of the equations of motion that give unified descriptions of G and U-type branes.
description: 24 pages, minor changes
Adiabatic pumping through a quantum dot in the Kondo regime: Exact results at the Toulouse limit
Creators: name: Schiller, Avraham
name: Silva, Alessandro
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Transport properties of ultrasmall quantum dots with a single unpaired electron are commonly modeled by the nonequilibrium Kondo model, describing the exchange interaction of a spin-1/2 local moment with two leads of noninteracting electrons. Remarkably, the model possesses an exact solution when tuned to a special manifold in its parameter space known as the Toulouse limit. We use the Toulouse limit to exactly calculate the adiabatically pumped spin current in the Kondo regime. In the absence of both potential scattering and a voltage bias, the instantaneous charge current is strictly zero for a generic Kondo model. However, a nonzero spin current can be pumped through the system in the presence of a finite magnetic field, provided the spin couples asymmetrically to the two leads. Tunneling through a Kondo impurity thus offers a natural mechanism for generating a pure spin current. We show, in particular, that one can devise pumping cycles along which the average spin pumped per cycle is closely equal to $\hbar$. By analogy with Brouwer's formula for noninteracting systems with two driven parameters, the pumped spin current is expressed as a geometrical property of a scattering matrix. However, the relevant %Alex: I replaced topological with geometrical in the sentence above scattering matrix that enters the formulation pertains to the Majorana fermions that appear at the Toulouse limit rather than the physical electrons that carry the current. These results are obtained by combining the nonequilibrium Keldysh Green function technique with a systematic gradient expansion, explicitly exposing the small parameter controlling the adiabatic limit.
description: 14 pages, 3 figures, revised version
Cavity cooling of a nanomechanical resonator by light scattering
Creators: name: Favero, Ivan
name: Karrai, Khaled
Publisher: name: arXiv
Year: 2007
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We present a novel method for opto-mechanical cooling of sub-wavelength sized nanomechanical resonators. Our scheme uses a high finesse Fabry-Perot cavity of small mode volume, within which the nanoresonator is acting as a position-dependant perturbation by scattering. In return, the back-action induced by the cavity affects the nanoresonator dynamics and can cool its fluctuations. We investigate such cavity cooling by scattering for a nanorod structure and predict that ground-state cooling is within reach.
description: 4 pages, 3 figures