pinecone/core-2020-05-10-deduplication huggingface dataset:
Spontaneous microcavity-polariton coherence across the parametric
  threshold: Quantum Monte Carlo studies

We investigate the appearance of spontaneous coherence in the parametric
emission from planar semiconductor microcavities in the strong coupling regime.
Calculations are performed by means of a Quantum Monte Carlo technique based on
the Wigner representation of the coupled exciton and cavity-photon fields. The
numerical results are interpreted in terms of a non-equilibrium phase
transition occurring at the parametric oscillation threshold: below the
threshold, the signal emission is incoherent, and both the first and the
second-order coherence functions have a finite correlation length which becomes
macroscopic as the threshold is approached. Above the threshold, the emission
is instead phase-coherent over the whole two-dimensional sample and intensity
fluctuations are suppressed. Similar calculations for quasi-one-dimensional
microcavities show that in this case the phase-coherence of the signal emission
has a finite extension even above the threshold, while intensity fluctuations
are suppressed
Higher Loop Nonplanar Anomalous Dimensions from Symmetry

In this article we study the action of the one loop dilatation operator on
operators with a classical dimension of order N. These operators belong to the
su(2) sector and are constructed using two complex fields Y and Z. For these
operators non-planar diagrams contribute already at the leading order in N and
the planar and large N limits are distinct. The action of the one loop and the
two loop dilatation operator reduces to a set of decoupled oscillators and
factorizes into an action on the Z fields and an action on the Y fields. Direct
computation has shown that the action on the Y fields is the same at one and
two loops. In this article, using the su(2) symmetry algebra as well as
structural features of field theory, we give compelling evidence that the
factor in the dilatation operator that acts on the Ys is given by the one loop
expression, at any loop order.Comment: 1+40 page
Nonlinear brain dynamics as macroscopic manifestation of underlying
  many-body field dynamics

Neural activity patterns related to behavior occur at many scales in time and
space from the atomic and molecular to the whole brain. Here we explore the
feasibility of interpreting neurophysiological data in the context of many-body
physics by using tools that physicists have devised to analyze comparable
hierarchies in other fields of science. We focus on a mesoscopic level that
offers a multi-step pathway between the microscopic functions of neurons and
the macroscopic functions of brain systems revealed by hemodynamic imaging. We
use electroencephalographic (EEG) records collected from high-density electrode
arrays fixed on the epidural surfaces of primary sensory and limbic areas in
rabbits and cats trained to discriminate conditioned stimuli (CS) in the
various modalities. High temporal resolution of EEG signals with the Hilbert
transform gives evidence for diverse intermittent spatial patterns of amplitude
(AM) and phase modulations (PM) of carrier waves that repeatedly re-synchronize
in the beta and gamma ranges at near zero time lags over long distances. The
dominant mechanism for neural interactions by axodendritic synaptic
transmission should impose distance-dependent delays on the EEG oscillations
owing to finite propagation velocities. It does not. EEGs instead show evidence
for anomalous dispersion: the existence in neural populations of a low velocity
range of information and energy transfers, and a high velocity range of the
spread of phase transitions. This distinction labels the phenomenon but does
not explain it. In this report we explore the analysis of these phenomena using
concepts of energy dissipation, the maintenance by cortex of multiple ground
states corresponding to AM patterns, and the exclusive selection by spontaneous
breakdown of symmetry (SBS) of single states in sequences.Comment: 31 page
Orthogonal variability modeling to support multi-cloud application configuration

Cloud service providers benefit from a vast majority of customers due to variability and making profit from commonalities between the cloud services that they provide. Recently, application configuration dimensions has been increased dramatically due to multi-tenant, multi-device and multi-cloud paradigm. This challenges the configuration and customization of cloud-based software that are typically offered as a service due to the intrinsic variability. In this paper, we present a model-driven approach based on variability models originating from the software product line community to handle such multi-dimensional variability in the cloud. We exploit orthogonal variability models to systematically manage and create tenant-specific configuration and customizations. We also demonstrate how such variability models can be utilized to take into account the already deployed application parts to enable harmonized deployments for new tenants in a multi-cloud setting. The approach considers application functional and non-functional requirements to provide a set of valid multi-cloud configurations. We illustrate our approach through a case study
Oxidative Stress in Hypobaric Hypoxia and Influence on Vessel-Tone Modifying Mediators

Increased pulmonary artery pressure is a well-known phenomenon of hypoxia and is seen in patients with chronic pulmonary diseases, and also in mountaineers on high altitude expedition. Different mediators are known to regulate pulmonary artery vessel tone. However, exact mechanisms are not fully understood and a multimodal process consisting of a whole panel of mediators is supposed to cause pulmonary artery vasoconstriction.\ud
\ud
We hypothesized that increased hypoxemia is associated with an increase in vasoconstrictive mediators and decrease of vasodilatators leading to a vasoconstrictive net effect. Furthermore, we suggested oxidative stress being partly involved in changement of these parameters.\ud
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Oxygen saturation (Sao2) and clinical parameters were assessed in 34 volunteers before and during a Swiss research expedition to Mount Muztagh Ata (7549 m) in Western China. Blood samples were taken at four different sites up to an altitude of 6865 m.\ud
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A mass spectrometry-based targeted metabolomic platform was used to detect multiple parameters, and revealed functional impairment of enzymes that require oxidation-sensitive cofactors. Specifically, the tetrahydrobiopterin (BH4)-dependent enzyme nitric oxide synthase (NOS) showed significantly lower activities (citrulline-to-arginine ratio decreased from baseline median 0.21 to 0.14 at 6265 m), indicating lower NO availability resulting in less vasodilatative activity. Correspondingly, an increase in systemic oxidative stress was found with a significant increase of the percentage of methionine sulfoxide from a median 6% under normoxic condition to a median level of 30% (p<0.001) in camp 1 at 5533 m. Furthermore, significant increase in vasoconstrictive mediators (e.g., tryptophan, serotonin, and peroxidation-sensitive lipids) were found.\ud
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During ascent up to 6865 m, significant altitude-dependent changes in multiple vessel-tone modifying mediators with excess in vasoconstrictive metabolites could be demonstrated. These changes, as well as highly significant increase in systemic oxidative stress, may be predictive for increase in acute mountain sickness score and changes in Sao2
Accessing and managing open medical resources in Africa over the Internet

Recent commentaries have proposed the advantages of using open exchange of data and informatics resources for improving health-related policies and patient care in Africa. Yet, in many African regions, both private medical and public health information systems are still unaffordable. Open exchange over the social Web 2.0 could encourage more altruistic support of medical initiatives. We have carried out some experiments to demonstrate the feasibility of using this approach to disseminate open data and informatics resources in Africa. After the experiments we developed the AFRICA BUILD Portal, the first Social Network for African biomedical researchers. Through the AFRICA BUILD Portal users can access in a transparent way to several resources. Currently, over 600 researchers are using distributed and open resources through this platform committed to low connections
Modeling organic iron-binding ligands in a three-dimensional biogeochemical ocean model

Most dissolved iron in the ocean is bound to organic molecules with strong conditional stability constants, known as ligands that are found at concentrations ranging from 0.2 to more than 10 nmol L− 1. In this work we report the first mechanistic description of ligand dynamics in two three-dimensional models of ocean biogeochemistry and circulation. The model for ligands is based on the concept that ligands are produced both from organic matter remineralization and phytoplankton processes, and that they are lost through bacterial and photochemical degradation, as well as aggregation and to some extent in the process of phytoplankton uptake of ligand-bound iron. A comparison with a compilation of in-situ measurements shows that the model is able to reproduce some large-scale features of the observations, such as a decrease in ligand concentrations along the conveyor belt circulation in the deep ocean, lower surface and subsurface values in the Southern Ocean, or higher values in the mesopelagic than in the abyssal ocean. Modeling ligands prognostically (as opposed to assuming a uniform ligand concentration) leads to a more nutrient-like profile of iron that is more in accordance with data. It however, also leads to higher surface concentrations of dissolved iron and negative excess ligand L⁎ in some ocean regions. This is probably an indication that with more realistic and higher ligand concentrations near the surface, as opposed to the traditionally chosen low uniform concentration, iron modelers will have to re-evaluate their assumption of low scavenging rates for iron. Given their sensitivity to environmental conditions, spatio-temporal variations in ligand concentrations have the potential to impact primary production via changes in iron limitation
A technical note on the bias in the estimation of the b-value and its uncertainty through the Least Squares technique

We investigate conceptually,
analytically, and numerically the biases in the estimation of the
b-value of the Gutenberg-Richter law and of 
its uncertainty made through the least
squares technique. The biases are introduced by the cumulation
operation for the cumulative form of the Gutenberg-Richter law, by
 the logarithmic transformation, and by the measurement errors on
the magnitude.
We find that the least squares technique, 
applied to the cumulative and binned form of
the Gutenberg-Richter law, produces strong bias in the b-value and
its uncertainty, whose amplitudes depend on the size of the sample.
Furthermore, the logarithmic transformation produces two different 
endemic bends in the Log(N) versus M curve.
This means that this plot
might produce fake significant departures from the
Gutenberg-Richter law. 
The effect of the measurement errors is negligible compared to those of
cumulation operation and logarithmic transformation.
The results obtained show that the least  squares technique should
never be used to determine the slope of the  Gutenberg-Richter law and 
its uncertainty
Magnetic propulsion of self-assembled colloidal carpets: efficient cargo transport via a conveyor-belt effect

We demonstrate a general method to assemble and propel highly maneuverable colloidal carpets which can be steered via remote control in any direction of the plane. These colloidal micropropellers are composed by an ensemble of spinning rotors and can be readily used to entrap, transport, and release biological cargos on command via a hydrodynamic conveyor-belt effect. An efficient control of the cargo transportation combined with remarkable 'healing' ability to surpass obstacles demonstrate a great potential towards development of multifunctional smart devices at the microscale
A comparison of classification techniques for the P300 speller

International audienceThis study assesses the relative performance characteristics of five established classification techniques on data collected using the P300 Speller paradigm, originally described by Farwell and Donchin (1988 Electroenceph. Clin. Neurophysiol. 70 510). Four linear methods: Pearson's correlation method (PCM), Fisher's linear discriminant (FLD), stepwise linear discriminant analysis (SWLDA) and a linear support vector machine (LSVM); and one nonlinear method: Gaussian kernel support vector machine (GSVM), are compared for classifying offline data from eight users. The relative performance of the classifiers is evaluated, along with the practical concerns regarding the implementation of the respective methods. The results indicate that while all methods attained acceptable performance levels, SWLDA and FLD provide the best overall performance and implementation characteristics for practical classification of P300 Speller data
Stability and variety - Products, organization and institutionalization in farm tourism

Products, collective organization and institutions are factors that shape farm tourism. The aim of this paper is to present new knowledge of the way these factors are designed and provide lessons for management in the sector. Research findings to date suggest these factors are varied but similarities within findings exist. However, while there have been a number of studies on the importance of each of the factors, few studies focus on the combined impact of them. This study attempts to go some way toward filling this knowledge gap. The empirical cases for the study are derived from three European locations: two regions in the Alps: North Tyrol in Austria and South Tyrol in Italy, and Norway. The breadth and variety of the product range differ. We also find clear contrasts between the cases when it comes to the structure of farm tourism organizations. However, the goals of the organizations are quite similar emphasizing three types of tasks: marketing, competence building and quality assurance. Concerning systems for quality assurance, a type of institutional factor, two cases are similar, while the third case (Norway) has a different (less strict) system. Based on a comparative analysis of the cases we develop a conceptual model showing the interdependence between products, organization and institutions in the farm tourism sector, and the influence of market and location. We provide some examples of application of the findings by various actors and agencies in tourism
A sequential data assimilation approach for the joint reconstruction of mantle convection and surface tectonics

International audienceWith the progress of mantle convection modelling over the last decade, it now becomes possible to solve for the dynamics of the interior flow and the surface tectonics to first order. We show here that tectonic data (like surface kinematics and seafloor age distribution) and mantle convection models with plate-like behaviour can in principle be combined to reconstruct mantle convection. We present a sequential data assimilation method, based on suboptimal schemes derived from the Kalman filter, where surface velocities and seafloor age maps are not used as boundary conditions for the flow, but as data to assimilate. Two stages (a forecast followed by an analysis) are repeated sequentially to take into account data observed at different times. Whenever observations are available, an analysis infers the most probable state of the mantle at this time, considering a prior guess (supplied by the forecast) and the new observations at hand, using the classical best linear unbiased estimate. Between two observation times, the evolution of the mantle is governed by the forward model of mantle convection. This method is applied to synthetic 2-D spherical annulus mantle cases to evaluate its efficiency. We compare the reference evolutions to the estimations obtained by data assimilation. Two parameters control the behaviour of the scheme: the time between two analyses, and the amplitude of noise in the synthetic observations. Our technique proves to be efficient in retrieving temperature field evolutions provided the time between two analyses is 10 Myr. If the amplitude of the a priori error on the observations is large (30 per cent), our method provides a better estimate of surface tectonics than the observations, taking advantage of the information within the physics of convection
The magnetic-distortion probe: Velocimetry in conducting fluids

International audienceA new type of velocimeter, capable of local velocity measurements in conducting fluids, is introduced. The principle of the " magnetic-distortion probe " is based on the measurement of the induced magnetic field by the flow of a conducting fluid in the vicinity of a localized magnetic field. The new velocimeter has no moving parts, and can be enclosed in a sealed cap, easing the implementation in harsh environments, such as liquid metals. The proposed method allows one to probe both the continuous part and fluctuations of the velocity, the temporal and spatial resolution being linked to the actual geometric configuration of the probe. A prototype probe has been tested in a gallinstan pipe flow and in a fully turbulent flow of liquid gallium generated by the counter rotation of two coaxial impellers in a cylinder. The signals have been compared to a reference potential probe and show very good agreement both for time-averaged velocities and turbulent fluctuations. The prototype is shown to detect motion from a few cm s −1 to a few m s −1. Moreover, the use of the magnetic-distortion probe with large-scale applied magnetic field is discussed
Evidence for the inside-out growth of the stellar mass distribution in galaxy clusters since z ~ 1

International audienceWe study the radial number density and stellar mass density distributions of satellite galaxies in a sample of 60 massive clusters at 0.04 <z< 0.26 selected from the Multi-Epoch Nearby Cluster Survey (MENeaCS) and the Canadian Cluster Comparison Project (CCCP). In addition to ~10 000 spectroscopically confirmed member galaxies, we use deep ugri-band imaging to estimate photometric redshifts and stellar masses, and then statistically subtract fore- and background sources using data from the COSMOS survey. We measure the galaxy number density and stellar mass density distributions in logarithmically spaced bins over 2 orders of magnitude in radial distance from the BCGs. For projected distances in the range 0.1 <R/R200< 2.0, we find that the stellar mass distribution is well-described by an NFW profile with a concentration of c = 2.03 ± 0.20. However, at smaller radii we measure a significant excess in the stellar mass in satellite galaxies of about 1011M⊙ per cluster, compared to these NFW profiles. We do obtain good fits to generalised NFW profiles with free inner slopes and to Einasto profiles. To examine how clusters assemble their stellar mass component over cosmic time, we compare this local sample to the GCLASS cluster sample at z ~ 1, which represents the approximate progenitor sample of the low-z clusters. This allows for a direct comparison, which suggests that the central parts (R< 0.4 Mpc) of the stellar mass distributions of satellites in local galaxy clusters are already in place at z ~ 1, and contain sufficient excess material for further BCG growth. Evolving towards z = 0, clusters appear to assemble their stellar mass primarily onto the outskirts, making them grow in an inside-out fashion
Voltammetry of redox analytes at trace concentrations with nanoelectrode ensembles

Gold nanoelectrodes ensembles (NEEs) have been prepared by electroless plating of Au nanoelectrode elements within the pores of a microporous\ud
polycarbonate template membrane. Cyclic voltammograms recorded in (ferrocenylmethyl) trimethylammonium hexafluorophosphate\ud
(FA+ PF6−) solutions showed that these NEEs operate in the “total-overlap” response regime, giving well resolved peak shaped voltammograms.\ud
Experimental results show that the faradaic/background currents ratios at the NEE are independent on the total geometric area of\ud
the ensemble, so that NEE can be enlarged or miniaturized at pleasure without influencing the very favorable signal/noise ratio. Differential\ud
pulse voltammetry (DPV) at the NEE is optimized for direct determinations at trace levels. DPV at NEE allowed the determination (with no\ud
preconcentration) of trace amounts of FA+, with a detection limit of 0.02M. The use of NEE and DPV in cytochrome c (cyt c) solutions\ud
showed the possibility to observe the direct electrochemistry of submicromolar concentration of the protein, even without the need of adding\ud
any promoter or mediator
Electronic structure of LiSi

Silicon is of special interest in lithium-ion batteries (LIBs) since it has large theoretical specific
capacity or volumetric capacity. The crystal structure, charge distribution and density of states of
LiSi as the Li-poorest side compound at the start of Li intercalation mechanism for Si anode in LIBs
has been studied by using Density Functional Theory calculations. The triangular pyramids are
formed by four Li atoms. Compared with the charge density of crystalline Si, the Si-Si covalent
bonds in LiSi become weak due to Li intercalation. On the other hand, the electrons around the Li
atoms in LiSi increase compared with metallic Li. The Li atoms in LiSi have negative charge of
0.830～0.843 compared with metallic Li. These electrons, which are transferred from p electrons in
the Si atoms, are mainly made of p electrons of the Li atoms. When considering the lithium
intercalation reaction from crystalline Si to LiSi, the average intercalation voltage is 0.4053 V
Transition from heterogeneous catalytic reaction to homogeneous one by variation of palladium particle size

Reduction of methylene blue with hydrazine was catalyzed by nearly mono-dispersed palladium particles of which diameters (2r0) ranged from 30 to 230 nm. The spectroscopically evaluated pseudo-first order reaction rate constants were proportional to r03α, where 3α varied from 2 to 3 with a decrease in the radius. The catalysis at large r0 proceeded heterogeneously, whereas that at small r0 occurred homogeneously. The relation between α and r0 allowed us to evaluate the thickness of the reaction layer to be 20 nm. The analysis of the diffusion-reaction model demonstrated the thickness did not vary largely with r0
Dynamic performance of existing double track railway bridges at resonance with the increase of the operational line speed

This article addresses the dynamic behaviour of double track simply supported bridges of short to medium span lengths (10 m < L < 25 m) belonging to conventional railway lines. These structures are susceptible to experience inadmissible levels of vertical vibrations when traversed by trains at high speeds, and in certain cases their dynamic performance may require to be re-evaluated in case of an increase of the traffic velocity above 200 km/h. In engineering consultancies, these structures have been traditionally analysed under the passage of trains at different speeds using planar models, neglecting the contribution of transverse vibration modes and also the flexibility of the elastomeric bearings. The study presented herein endeavours to evaluate the influence of these two aspects in the verification of the Serviceability Limit State of vertical accelerations, which is of great interest in order to guarantee a conservative prediction of the dynamic behaviour. In the present study, the dynamic response of representative slab and girder bridges has been evaluated using an orthotropic plate finite element model, leading to practical conclusions regarding the circumstances under which the above mentioned factors should be considered in order to adequately evaluate the transverse vibration levels of the deck