pinecone/core-2020-05-10-deduplication huggingface dataset:
Cerebroespinalfluid control of neurogenesis induced by retinoic acid during early brain development

Producción CientíficaEmbryonic-cerebrospinal fluid (E-CSF) plays crucial roles in early brain development including the control
of neurogenesis. Although FGF2 and lipoproteins present in the E-CSF have previously been shown
to be involved in neurogenesis, the main factor triggering this process remains unknown. E-CSF contains
all-trans-retinol and retinol-binding protein involved in the synthesis of retinoic acid (RA), a neurogenesis
inducer. In early chick embryo brain, only the mesencephalic-rombencephalic isthmus (IsO) is able to
synthesize RA. Here we show that in chick embryo brain development: (1) E-CSF helps to control RA synthesis
in the IsO by means of the RBP and all-trans-retinol it contains; (2) E-CSF has retinoic acid activity,
which suggests it may act as a diffusion pathway for RA; and (3) the influence of E-CSF on embryonic
brain neurogenesis is to a large extent due to its involvement in RA synthesis. These data help to
understand neurogenesis from neural progenitor cells2015-05-2
Non-destructive characterisation of the Elephant Moraine 83227 meteorite using confocal Raman, micro-energy-dispersive X-ray fluorescence and Raman-scanning electron microscope-energy-dispersive X-ray microscopies

The application of a non-destructive analytical procedure to characterise the mineral phases in meteorites is a key issue in order to
preserve this type of scarce materials. In the present work, the Elephant Moraine 83227 meteorite, found in Antarctica in 1983
and originated from 4 Vesta asteroid, was analysed by micro-Raman spectroscopy, micro-energy-dispersive X-ray fluorescence
and the structural and chemical analyser (Raman spectroscopy coupled with scanning electron microscopy-energy-dispersive
spectroscopy) working in both point-by-point and image modes. The combination of all these techniques allows the extraction of,
at the same time, elemental, molecular and structural data of the studied microscopic area of the meteorite. The most relevant
results of the Elephant Moraine 83227 were the finding of tridymite for the first time in a 4 Vesta meteorite, along with quartz,
which means that the meteorite suffered high temperatures at a certain point. Moreover, both feldspar and pyroxenewere found as
the main mineral phases in the sample. Ilmenite, apatite, chromite and elemental sulphur were also detected as secondary
minerals. Finally, calcite was found as a weathering product, which was probably formed in terrestrial weathering processes of
the pyroxene present in the sample. Besides, Raman spectroscopy provided information about the conditions that the meteorite
experienced; the displacements in some feldspar Raman bands were used to estimate the temperature and pressure conditions to
which the Elephant Moraine 83227 was subjected, because we obtained both low and high formation temperature feldspar.Proyecto MINECO Retos de la Sociedad. Ref. ESP2014-56138-C3-2-
Socioeconomic position and health-seeking behavior for hearing loss among older adults in England

Objective. To examine whether socioeconomic position (SEP) is associated with progression in the health-seeking process for hearing loss.    Method. Logistic regression of data from a cross-sectional survey representative of noninstitutionalized, 50 years and older population of England (ELSA wave 2, 2004). Using self-reported hearing difficulty as starting point, we examined the association between SEP and health-seeking behaviors in 6 stages leading to hearing aid acquisition and use.    Results. Higher SEP was associated with lower odds of self-reported hearing difficulty, adjusted odds ratio [OR] = 0.87 (95% confidence interval [CI] 0.83–0.91, p < .001). There was marginal negative association between higher SEP and receiving hearing aid recommendation (adjusted OR = 0.88, 95% CI 0.78–0.99, p = .05). SEP was not associated with any other stage of health-seeking behavior.    Discussion. Among the noninstitutionalized older population of England, SEP-related inequalities exist in the prevalence of self-reported hearing loss. However, SEP is not strongly associated with progression in the remaining stages of health-seeking process during and after an individual’s contact with the health system
Mechanisms of kinetic trapping in self-assembly and phase transformation

In self-assembly processes, kinetic trapping effects often hinder the
formation of thermodynamically stable ordered states. In a model of viral
capsid assembly and in the phase transformation of a lattice gas, we show how
simulations in a self-assembling steady state can be used to identify two
distinct mechanisms of kinetic trapping. We argue that one of these mechanisms
can be adequately captured by kinetic rate equations, while the other involves
a breakdown of theories that rely on cluster size as a reaction coordinate. We
discuss how these observations might be useful in designing and optimising
self-assembly reactions
The Multithreaded version of FORM

We present TFORM, the version of the symbolic manipulation system FORM that
can make simultaneous use of several processors in a shared memory
architecture. The implementation uses Posix threads, also called pthreads, and
is therefore easily portable between various operating systems. Most existing
FORM programs will be able to take advantage of the increased processing power,
without the need for modifications. In some cases some minor additions may be
needed. For a computer with two processors a typical improvement factor in the
running time is 1.7 when compared to the traditional version of FORM. In the
case of computers with 4 processors a typical improvement factor in the
execution time is slightly above 3.Comment: 18 page
Problem formulation for truth-table invariant cylindrical algebraic
  decomposition by incremental triangular decomposition

Cylindrical algebraic decompositions (CADs) are a key tool for solving
problems in real algebraic geometry and beyond. We recently presented a new CAD
algorithm combining two advances: truth-table invariance, making the CAD
invariant with respect to the truth of logical formulae rather than the signs
of polynomials; and CAD construction by regular chains technology, where first
a complex decomposition is constructed by refining a tree incrementally by
constraint. We here consider how best to formulate problems for input to this
algorithm. We focus on a choice (not relevant for other CAD algorithms) about
the order in which constraints are presented. We develop new heuristics to help
make this choice and thus allow the best use of the algorithm in practice. We
also consider other choices of problem formulation for CAD, as discussed in
CICM 2013, revisiting these in the context of the new algorithm
Using the Regular Chains Library to build cylindrical algebraic
  decompositions by projecting and lifting

Cylindrical algebraic decomposition (CAD) is an important tool, both for
quantifier elimination over the reals and a range of other applications.
Traditionally, a CAD is built through a process of projection and lifting to
move the problem within Euclidean spaces of changing dimension. Recently, an
alternative approach which first decomposes complex space using triangular
decomposition before refining to real space has been introduced and implemented
within the RegularChains Library of Maple. We here describe a freely available
package ProjectionCAD which utilises the routines within the RegularChains
Library to build CADs by projection and lifting. We detail how the projection
and lifting algorithms were modified to allow this, discuss the motivation and
survey the functionality of the package
Yield stress fluids method to determine the pore size distribution of a porous medium

In this paper a new method is presented in order to determine the pore size distribution in a porous medium. This original technique uses the rheological properties of some non-Newtonian yield stress fluids flowing through the porous sample. This technique is based on the capillary bundle model (like the other classical methods) which, despite its apparent simplicity, is capable of properly characterizing the percolating pore size distribution. Then this distribution can be simply obtained from the measurement of the total flow rate as a function of the imposed pressure gradient. The present technique is successfully tested analytically and numerically for usual pore size distributions such as the Gaussian mono and multimodal distributions, using Bingham and Casson fluids. The technique can also be extended to any yield stress fluid and any kind of distribution
An experimental analysis of fluid structure interaction on a flexible hydrofoil in various flow regimes including cavitating flow

The authors gratefully acknowledge the technical staff of IRENav for its contribution to the experimental set up.The structural response of a rectangular cantilevered flexible hydrofoil submitted to various flow regimes is analyzed through an original experiment carried out in a hydrodynamic tunnel at a Reynolds number of 0.75 × 10 6 . The experiment considers static and transient regimes. The latter consists of transient pitching motions at low and fast pitching velocities. The experiments are also performed for cavitating flow. The structural response is analyzed through the measurement of the free foil tip section displacement using a high speed video camera and surface velocity vibrations using a laser doppler vibrometer.
In non cavitating flows, it is shown that the structural response is linked to the hydrodynamic loading, which is governed by viscous effects such as laminar to turbulent transition induced by Laminar Separation Bubble (LSB), and stall. It is also observed that the foil elastic displacement depends strongly on the pitching velocity. Large overshoots and hysteresis effect are observed as the pitching velocity increases. Cavitation induces a large increase of the vibration level due to hydrodynamic loading unsteadiness and change of modal response for specific frequencies. The experimental results presented in this paper will help to develop high fidelity fluid–structure interaction models in naval applications
Optimal Information Transmission in Organizations: Search and Congestion

We propose a stylized model of a problem-solving organization whose internal communication structure is given by a fixed network. Problems arrive randomly anywhere in this network and must find their way to their respective specialized solvers by relying on local information alone. The organization handles multiple problems simultaneously. For this reason, the process may be subject to congestion. We provide a characterization of the threshold of collapse of the network and of the stock of floating problems (or average delay)
that prevails below that threshold. We build upon this characterization to address a design problem: the determination of what kind of network architecture optimizes performance for any given problem arrival rate. We conclude that, for low arrival rates, the optimal network is very polarized (i.e. star-like or centralized), whereas it is largely homogenous (or decentralized)
for high arrival rates. These observations are in line with a common transformation
experienced by information-intensive organizations as their work flow has risen in recent years.Publicad
Renormalization of electron self-energies via their interaction with spin excitations: A first-principles investigation

Access to magnetic excitation spectra of single atoms deposited on surfaces is nowadays possible by means of low-temperature inelastic scanning tunneling spectroscopy. We present a first-principles method for the calculation of inelastic tunneling spectra utilizing the Korringa-Kohn-Rostoker Green function method combined with time-dependent density functional theory and many-body perturbation theory. The key quantity is the electron self-energy describing the coupling of the electrons to the spin excitation within the adsorbate. By investigating Cr, Mn, Fe, and Co adatoms on a Cu(111) substrate, we spin-characterize the spectra and demonstrate that their shapes are altered by the magnetization of the adatoms, of the tip and the orbital decay into vacuum. Our method also predicts spectral features more complex than the steps obtained by simpler models for the adsorbate (e.g., localized spin models
Inflation by alignment

Pseudo-Goldstone bosons (pGBs) can provide technically natural inflatons, as has been comparatively well-explored in the simplest axion examples. Although inflationary success requires trans-Planckian decay constants, f ≳ Mp, several mechanisms have been proposed to obtain this, relying on (mis-)alignments between potential and kinetic energies in multiple-field models. We extend these mechanisms to a broader class of inflationary models, including in particular the exponential potentials that arise for pGB potentials based on noncompact groups (and so which might apply to moduli in an extra-dimensional setting). The resulting potentials provide natural large-field inflationary models and can predict a larger primordial tensor signal than is true for simpler single-field versions of these models. In so doing we provide a unified treatment of several alignment mechanisms, showing how each emerges as a limit of the more general setup
The Thermodynamic Limit in Mean Field Spin Glass Models

We present a simple strategy in order to show the existence and uniqueness of
the infinite volume limit of thermodynamic quantities, for a large class of
mean field disordered models, as for example the Sherrington-Kirkpatrick model,
and the Derrida p-spin model. The main argument is based on a smooth
interpolation between a large system, made of N spin sites, and two similar but
independent subsystems, made of N_1 and N_2 sites, respectively, with
N_1+N_2=N. The quenched average of the free energy turns out to be subadditive
with respect to the size of the system. This gives immediately convergence of
the free energy per site, in the infinite volume limit. Moreover, a simple
argument, based on concentration of measure, gives the almost sure convergence,
with respect to the external noise. Similar results hold also for the ground
state energy per site
Color in poly(3, 4-ethylenedioxythiophene) with profound implications for electronic, electrochemical, and optical functions

Poly(3, 4-ethylenedioxythiophene) (PEDOT) films have been synthesized by a facile electropolymerization route by using poly(-diallyldimethylammonium) chloride (PDDA) as the counter-ion source. To enhance their efficacy, the fullerene derivative N-methyl fulleropyrrolidine (N-FP) was embedded in the PEDOT/PDDA films; the electron-conducting ability of the N-FP came to the fore, as the conductivity, optical contrast, and ion-storage capacity were greater in the PEDOT/PDDA/N-FP film than in the PEDOT/PDDA film. Both the PEDOT/PDDA and PEDOT/PDDA/N-FP films showed an unprecedented dramatic digression from the expected optical response of conventional PEDOT, exhibiting distinct π-π * absorptions in the visible region in air, corresponding to a bandgap of 1.1-1.3 eV, which is outside the established range (1.6-1.7 eV). The neutral state of these films showed split components, which was simultaneously accompanied by a reversible color change from bright blue (in oxidized form) to deep brown (in reduced form). This is a most unusual color transition for PEDOT, as it opposes the well-established colors that vacillate between dark blue (reduced) and sky blue (oxidized) tones. Atomic force microscopy and Kelvin probe force microscopy provided evidence for the higher nanoscale current-carrying capacity and lower localized work function for PEDOT/PDDA/N-FP than for PEDOT/PDDA; both the energetics and conductivity are conducive for fast redox switching. The serendipitous but easily reproducible synthesis method and results for PEDOT/PDDA and PEDOT/PDDA/N-FP pave the way for the utilization of this material for electronic, electrochemical, and optical functions. This is different from what is currently known about the molecular-level feature control of macroscopic propertie
Gradient flow of O(N) nonlinear sigma model at large N

We study the gradient flow equation for the O(N) nonlinear sigma model in two dimensions at large N. We parameterize solution of the field at flow time t in powers of bare fields by introducing the coefficient function X n for the n-th power term (n = 1, 3, ··· ). Reducing the flow equation by keeping only the contributions at leading order in large N, we obtain a set of equations for X n ’s, which can be solved iteratively starting from n = 1. For n = 1 case, we find an explicit form of the exact solution. Using this solution, we show that the two point function at finite flow time t is finite. As an application, we obtain the non-perturbative running coupling defined from the energy density. We also discuss the solution for n = 3 case
Bargaining over a common categorisation

Two agents endowed with different categorisations engage in bargaining to reach an understanding and agree on a common categorisation. We model the process as a simple non-cooperative game and demonstrate three results. When the initial disagreement is focused, the bargaining process has a zero-sum structure. When the disagreement is widespread, the zero-sum structure disappears and the unique equilibrium requires a retraction of consensus: two agents who individually associate a region with the same category end up rebranding it under a different category. Finally, we show that this last equilibrium outcome is Pareto dominated by a cooperative solution that avoids retraction; that is, the unique equilibrium agreement may be inefficient
The Ontology of Organisms: Mechanistic Modules or Patterned Processes?

Though the realm of biology has long been under the philosophical rule of the mechanistic magisterium, recent years have seen a surprisingly steady rise in the usurping prowess of process ontology. According to its proponents, theoretical advances in the contemporary science of evo-devo have afforded that ontology a particularly powerful claim to the throne: in that increasingly empirically confirmed discipline, emergently autonomous, higher-order entities are the reigning explanantia. If we are to accept the election of evo-devo as our best conceptualisation of the biological realm with metaphysical rigour, must we depose our mechanistic ontology for failing to properly “carve at the joints” of organisms? In this paper, I challenge the legitimacy of that claim: not only can the theoretical benefits offered by a process ontology be had without it, they cannot be sufficiently grounded without the metaphysical underpinning of the very mechanisms which processes purport to replace. The biological realm, I argue, remains one best understood as under the governance of mechanistic principles
Role of the boundary conditions in the Wigner-Seitz approximation applied to the neutron star inner crust

The influence of the boundary conditions used in the Wigner-Seitz (WS) approximation applied to the neutron star inner crust is examined. The generalized energy functional method which includes the neutron and proton pairing correlations is used. Predictions of two versions of the boundary conditions are compared with each other. The uncertainties in the equilibrium configuration (Z,R_c) of the crust, where Z is the proton charge and R_c, the radius of the WS cell, correspond to variation of Z by 2 - 6 units and of R_c, by 1 - 2 fm. The effect of the boundary conditions is enhanced at increasing density. These uncertainties are smaller than the variation of Z and R_c coming from the pairing effects. In the case of high densities, k_F greater than 1 1/fm, the most important uncertainty occurs in the value of the neutron gap. In the WS approximation, it originates from the shell effect in the neutron single-particle spectrum which is rather pronounced in the case of larger k_F and, correspondingly, small R_c values, but it becomes negligible at lower density near the drip point. An approximate recipe to avoid this uncertainty is suggested
Ocean redox structure across the Late Neoproterozoic Oxygenation Event: A nitrogen isotope perspective

International audienceThe end of the Neoproterozoic Era (1000 to 541 Ma) is widely believed to have seen the transition from a dominantly anoxic to an oxygenated deep ocean. This purported redox transition appears to be closely linked temporally with metazoan radiation and extraordinary perturbations to the global carbon cycle. However, the geochemical record of this transition is not straightforward, and individual data sets have been variably interpreted to indicate full oxygenation by the early Ediacaran Period (635 to 541 Ma) and deep ocean anoxia persevering as late as the early Cambrian. Because any change in marine redox structure would have profoundly impacted nitrogen nutrient cycling in the global ocean, the N isotope signature of sedimentary rocks (δ15Nsed) should reflect the Neoproterozoic deep-ocean redox transition. We present new N isotope data from Amazonia, northwest Canada, northeast Svalbard, and South China that span the Cryogenian glaciations (∼750 to 580 Ma). These and previously published data reveal a Nisotope distribution that closely resembles modern marine sediments, with a mode in δ15N close to +4 and range from −4 to +11. No apparent change is seen between the Cryogenian and Ediacarian. Data from earlier Proterozoic samples show a similar distribution, but shifted slightly towards more negative δ15N values and with a wider range. The most parsimonious explanation for the similarity of these Nisotopedistribution is that as in the modern ocean, nitrate (and hence O2) was stable in most of the middle–late Neoproterozoic ocean, and possibly much of Proterozoic Eon. However, nitrate would likely have been depleted in partially restricted basins and oxygen minimum zones (OMZs), which may have been more widespread than in the modern ocean
Inertial collapse of liquid rings

International audienceLiquid rings can be generated in the Leidenfrost state using liquid oxygen of low boiling point (-183 degrees C) and high magnetic susceptibility, allowing one to 'sculpt' the liquid into a ring shape using an annular magnet. When the magnetic field is turned off, the ring shrinks back into a puddle with a constant acceleration. A potential flow approach accurately describes the dynamics of closure with an equation reminiscent of the Rayleigh-Plesset equation for the collapse of transient cavities
Pipeline and Data Parallel Hybrid Indexing Algorithm for Multi-core Platform

Part 5: Modelling and SimulationInternational audienceThe scale and growth rate of today’s text collection bring new challenges for index construction. To tackle this problem, Pipeline and Data Parallel Hybrid Algorithm (PDPH), is proposed to improve the indexing performance for multi-core platform. Compared to existing sequential indexing algorithms, Pipeline and data parallelism are introduced by the PDPH to improve the algorithm flexibility and scale the performance with more cores. Evaluations showed this algorithm can improve index construction speed for multi-core platform