pinecone/core-2020-05-10-deduplication huggingface dataset:
Integrated polymer micro-ring resonators for optical sensing applications

International audienceMicro-resonators (MR) have become a key element for integrated optical sensors due to their integration capability and their easy fabrication with low cost polymer materials. Nowadays, there is a growing need on MRs as highly sensitive and selective functions especially in the areas of food and health. The context of this work is to implement and study integrated micro-ring resonators devoted to sensing applications. They are fabricated by processing SU8 polymer as core layer and PMATRIFE polymer as lower cladding layer. The refractive index of the polymers and of the waveguide structure as a function of the wavelength are presented. Using these results, a theoretical study of the coupling between ring and straight waveguides has been undertaken in order to define the MR design. Sub-micronic gaps of 0.5 µm to 1 µm between the ring and the straight waveguides have been successfully achieved with UV (i-lines) photolithography. Different superstrates such as air, water and aqueous solutions with glucose at different concentrations have been studied. First results show a good normalized transmission contrast of 0.98, a resonator quality factor around 1.5x10 4 corresponding to a coupling ratio of 14.7 % and ring propagation losses around 5 dB/cm. Preliminary sensing experiments have been performed for different concentrations of glucose; a sensitivity of 115 ± 8 nm/RIU at 1550 nm has been obtained with this couple of polymers
Piezo-force and Vibration Analysis of ZnO Nanowire Arrays for Sensor Application

To estimate the potential of ZnO nanostructures for force sensing applications, arrays of single nanowires and arrays of nanowire bundles have been fabricated by wet chemical growth method. The piezoelectrical and electrical properties of the single nanowires have been investigated by atomic force microscopy based techniques. The piezoelectric constant d33 = 15 pm/V has been determined from vibration analyses. The electrical response in the range up to 400 fA upon applying force between 40 nN and 1 μN has been recorded. The nanowire bundles were studied by electro-mechanical macro probing technique within the force range 1 - 10 mN, where a reproducible response in pA range has been measured
Clinical and Molecular Inflammatory Response in Sjögren Syndrome–Associated Dry Eye Patients Under Desiccating Stress

Producción CientíficaTo evaluate the response of the lacrimal function unit in Sjogren syndrome (SS)-associated dry eye patients exposed to 2 simulated daily life environ-mental conditions.
Fourteen female SS dry eye patients were exposed for 2 hours to a controlled normal condition (23 C, 45% relative humidity, and air flow 0.10 m/s) and a controlled adverse condition that simulates desic- cating stress (23 C, 5% relative humidity, and air flow 0.10 m/s). The following dry eye tests were performed before and after the exposure: tear osmolarity, phenol red thread test, conjunctival hyperemia, fluorescein tear break-up time, corneal fluorescein staining, conjunctival lissamine green staining, and Schirmer test. Levels of 16 molecules were analyzed in tears by multiplex immu- nobead analysis.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA174U14
Unexpected school reform: academisation of primary schools in England

The change of government in 2010 provoked a large structural change in the English education landscape. Unexpectedly, the new government offered primary schools the chance to have ‘the freedom and the power to take control of their own destiny’, with better performing schools given a green light to fast track convert to become an academy school. In England, schools that become academies have more freedom over many ways in which they operate, including curriculum design, budgets, staffing issues and the shape of the academic year. However, the change to allow primary school academisation has been controversial. This paper reports estimates of the causal effect of academy enrolment on primary school pupils. While the international literature provides growing evidence on the effect of school autonomy in a variety of contexts, little is known about the effect of autonomy on primary schools (which are typically much smaller than secondary schools) and in contexts where the converting school is not deemed to be failing or disadvantaged. The key findings are that English primary schools did change their mode of operation after the exogenous policy change, utilising more autonomy and changing spending behaviour, but this did not lead to improved pupil performance
Validating the detection of everyday concepts in visual lifelogs

The Microsoft SenseCam is a small lightweight wearable camera used to passively capture photos and other sensor readings from a use s day-today activities. It can capture up to 3,000 images per day, equating to almost 1 million images per year. It is used to aid memory by creating a personal multimedia lifelog, or visual recording of the wearer s life. However the sheer volume of image data captured within a visual lifelog creates a number of challenges, particularly for locating relevant content. Within this work, we explore the applicability of semantic concept detection, a method often used within video retrieval, on the novel domain of visual lifelogs. A concept detector models the correspondence between low-level visual features and highlevel semantic concepts (such as indoors, outdoors, people, buildings, etc.) using supervised machine learning. By doing so it determines the probability of a concept s presence. We apply detection of 27 everyday semantic concepts on a lifelog collection composed of 257,518 SenseCam images from 5 users. The results were then evaluated on a subset of 95,907 images, to determine the precision for detection of each semantic concept and to draw some interesting inferences on the lifestyles of those 5 users. We additionally present future applications of concept detection within the domain of lifelogging
The Role of Social Capital in the Adoption of Firewood Efficient Stoves in the Northern Peruvian Andes

This paper explores rural households’ adoption of a new cooking technology in the Northern Peruvian Andes. It exploits a development intervention which distributed and installed, at no cost, firewood efficient stoves in the rural communities of Chalaco District. Using first hand data, collected from the beneficiary villages, this research investigates how village technology adoption patterns and village social capital mutually interact and influence the individual household’s adoption decision. The results in this paper indicate that the effect of village adoption patterns on the household’s adoption decision is significantly higher in villages with stronger social capital and that the marginal impact of social capital may be negative if village success in adoption is relatively low. It is also shown that only the proportion of adopters that did not experience problems with their own stoves has a positive impact on individual household adoption through its interaction with social capital, while the reverse is true for the village proportion of adopters experiencing problems with the new cooking technology. In this study measures of social capital were collected prior to the intervention; therefore, reverse causality should not be a critical issue in identifying the effects of this social variable. Village unobservable factors are not likely to drive the observed patterns in the data; this paper also shows that village success in adoption has a negative effect on the decision to uninstall the stove among beneficiary non users and that this effect is also increasing in village social capital. The results point to the importance of village social structures in the success of development interventions.
Estimating Diffusion Rates for Telecommunications: Evidence from European Union

We study and evaluate the role of geographical, economic and social determinants of telecommunication services in European Union.  We use a logistic model with spatial covariates to estimate the demand function for telecommunications in the Union. Our results show that different types of interconnections generate diverse rates of diffusion for country specific demand. The impact on telecommunications from countries with geographical, economic or social similarities differs based on those characteristics. Omitted variable bias from not modeling spatial interdependence is limited in models under spatial connectivity criteria. This satisfies the statistical inference drawn by previous empirical studies regarding determinants of telecommunications. On the other hand, it is worth noting that we find significant omitted telecommunications variable bias under economic or social connectivity criteria.
Diversity of AMF associated with Ammophila arenaria ssp. arundinacea in Portuguese sand dunes

Abstract  Dune vegetation is essential for the formation and preservation of sand dunes and the protection of the coast line. Coastal sand dunes are harsh environments where arbuscular mycorrhizal fungi (AMF) play an important role in promoting plant establishment and growth. We present a study of the diversity of AMF associated with A. arenaria ssp. arundinacea in two locations of the Portuguese coast under a Mediterranean climate. These two locations were selected to compare a well-preserved dune system from a protected area with a degraded dune system from a public beach. AMF diversity was assessed mainly by cloning and sequencing of a fragment of the ribosomal SSU using the primer NS31 and AM1. Most of the 89 AMF clones obtained from the rhizosphere and roots of A. arenaria belonged to the genus Glomus, the largest clade within the Glomeromycota. Higher AMF diversity was found in the least disturbed site, in which spores of Scutellospora persica, Glomus constrictum and Glomus globiferum were found in the rhizosphere of A. arenaria.http://dx.doi.org/10.1007/s00572-006-0070-
Identification of selected seaweed polysaccharides (phycocolloids) by vibrational spectroscopy (FTIR-ATR and FT-Raman)

The wide industrial application of phycocolloids (e.g. alginates, agar and carrageenans) is based on their
particular properties to form gels in aqueous solution. These seaweed polysaccharides present a chemical
structure related with the taxonomic position of the algae: carrageenans are produced by carrageenophytes
(red algae belonging mainly to the genera Kappaphycus, Eucheuma, Chondrus, Gigartina and
Chondracanthus). Recently, new spectroscopic techniques have provided more accurate identification of
the natural composition of the polysaccharides produced by these seaweeds. With the combination of
two spectroscopic techniques (FTIR-ATR and FT-Raman) it is possible to identify the principal seaweed
colloids in ground seaweed samples as in extracted material. Since the seaweed samples receive the
minimum of handling and treatment (e.g. they are simply dried and ground), the composition determined
represents, as accurately as possible, the native composition of the phycocolloids
Software architecture for the cloud - a roadmap towards control-theoretic, model-based cloud architecture

The cloud is a distributed architecture providing resources as tiered services. Through the principles of service-orientation and generally provided using virtualisation, the deployment and provisioning of applications can be managed dynamically, resulting in cloud platforms and applications as interdependent adaptive systems. Dynamically adaptive systems require a representation of requirements as dynamically manageable models, enacted through a controller implementing a feedback look based on a control-theoretic framework. We argue that a control-theoretic, model-based architectural framework for the cloud is needed. While some critical aspects such as uncertainty have already been taken into account, what has not been accounted for are challenges resulting from the cloud architecture as a multi-tiered, distributed environment.\ud
We identify challenges and define a framework that aims at a better understanding and a roadmap towards control-theoretic, model-based cloud architecture - driven by software architecture concerns
Electrical Activation Of The Ventricular Myocardium Of The Crocodile Crocodylus Johnstoni: A Combined Microscopic And Electrophysiological Study

We mapped the sequence of ventricular depolarization in the crocodile Crocodylus johnstoni. We also attempted to find specialized conduction tissue within the ventricular myocardium. Electrical recordings with miniature multi-point electrodes revealed two strands of rapidly conducting tissue (channels) within the interventricular septum, suggestive of conductive tissue pathways. From these septal channels, wavefronts of excitation swept around each ventricle. Electrical recordings did not indicate that there was conductive tissue in the wall of either ventricle. Similarly, microscopic studies of the septal channels provided no indication of specialized conductive tissue. We suggest that the channels of early septal depolarization provide the crocodile heart with a high speed depolarization pathway functionally analogous to a rudimentary conductive system
Investigation of the stress-strain state of the laminated shallow shells by R-functions method combined with spline-approximation

The bending behavior of the laminated shallow shells under static loading has been studied using the R functions theory together with the spline-approximation. Formulation is based on the first order shear deformation theory. Due to usage of the R-functions theory the laminated shallow shells with complex shape and different types of the boundary conditions can be investigated. Application of the spline-approximation allows getting reliable and validated results for non concave domains and domains with holes. The proposed method is implemented in the appropriate software in framework of the mathematical package MAPLE. The analysis of influence of certain factors (curvature, packing of layers, geometrical parameters, boundary conditions) on a stress-strain state is carried out for shallow shells with cut-outs. The comparison of obtained results with those already known from literature and results obtained by using ANSYS are also presented
Perturbed angular correlation study of Ta-181-doped PbTi1-xHfxO3 compounds

In this work, the hyperfine quadrupole interaction at Ta-doped PbTi1-xHfxO3 polycrystalline samples is studied for the first time. Powders with x=0.25, 0.50 and 0.75 were prepared and characterized by X-ray diffraction analysis. Perturbed Angular Correlation (PAC) analyses were done as a function of temperature, using low concentration Ta-181 nuclei as probes. In the ferroelectric and paraelectric phases of these compounds two sites were occupied by the probes. For each site the quadrupole frequency, asymmetry and relative distribution width parameters were obtained as a function of temperature above and below the Curie temperature (T-C). One of these sites was assigned to the regular Ti-Hf site, while the other one was assigned to some kind of defect. The behavior of the hyperfine parameters as a function of temperature was analyzed in terms of a recent published phase diagram and the presence of disorder below and above T-C. For the three compositions measured, the obtained hyperfine parameters present discontinuities which correspond to the ferroelectric-paraelectric phase transition. In both phases it was found broad frequency distributed interactions. The disorder in the electronic distribution would be responsible for the broad line width of the hyperfine interaction. (C) 2012 Elsevier B.V. All rights reserved
Neutron features at the UPM neutronics hall

The neutronics hall of the Nuclear Engineering Department at the Polytechnical University of Madrid has been characterized. The neutron spectra and the ambient dose equivalent produced by an 241AmBe source were measured at various source-to-detector distances on the new bench. Using Monte Carlo methods a detailed model of the neutronics hall was designed, and neutron spectra and the ambient dose equivalent were calculated at the same locations where measurements were carried out. A good agreement between measured and calculated values was found
Confined Brownian ratchets

We analyze the dynamics of Brownian ratchets in a confined environment. The
motion of the particles is described by a Fick-Jakobs kinetic equation in which
the presence of boundaries is modeled by means of an entropic potential. The
cases of a flashing ratchet, a two-state model and a ratchet under the
influence of a temperature gradient are analyzed in detail. We show the
emergence of a strong cooperativity between the inherent rectification of the
ratchet mechanism and the entropic bias of the fluctuations caused by spatial
confinement. Net particle transport may take place in situations where none of
those mechanisms leads to rectification when acting individually. The combined
rectification mechanisms may lead to bidirectional transport and to new routes
to segregation phenomena. Confined Brownian ratchets (CBR) could be used to
control transport in mesostructures and to engineer new and more efficient
devices for transport at the nanoscale
Competition between s-wave order and d-wave order in holographic
  superconductors

We study competition between s-wave order and d-wave order through two
holographic superconductor models. We find that once the coexisting phase
appears, it is always thermodynamically favored, and that the coexistence phase
is narrow and one condensate tends to kill the other. The phase diagram is
constructed for each model in terms of temperature and the ratio of charges of
two orders. We further compare the behaviors of some thermodynamic quantities,
and discuss the different aspects and identical ones between two models.Comment: 3 figures added, accepted by JHE
The Spectra of Heterotic Standard Model Vacua

A formalism for determining the massless spectrum of a class of realistic
heterotic string vacua is presented. These vacua, which consist of SU(5)
holomorphic bundles on torus-fibered Calabi-Yau threefolds with fundamental
group Z_2, lead to low energy theories with standard model gauge group (SU(3)_C
x SU(2)_L x U(1)_Y)/Z_6 and three families of quarks and leptons. A methodology
for determining the sheaf cohomology of these bundles and the representation of
Z_2 on each cohomology group is given. Combining these results with the action
of a Z_2 Wilson line, we compute, tabulate and discuss the massless spectrum.Comment: 41+1pp, 2 fig
Atiyah-Manton Approach to Skyrmion Matter

We propose how to approach, and report on the first results in our effort
for, describing nuclear matter starting from the solitonic picture of baryons
which is supposed to represent QCD for large number of colors. For this
purpose, the instanton-skyrmion connection of Atiyah and Manton is exploited to
describe skyrmion matter. We first modify 't Hooft's multi-instanton solution
so as to suitably incorporate proper dynamical variables into the skyrmion
matter and then by taking these variables as variational parameters, we show
that they cover a configuration space sufficient to adequately describe the
ground state properties of nuclear matter starting from the skyrmion picture.
Our results turn out to be comparable to those so far found in different
numerical calculations, with our solution reaching stability at high density
for a crystal structure and obtaining a comparable value for the energy per
baryon at the minimum, thus setting the stage for the next step
Hot Forging of a Cladded Component by Automated GMAW Process

Weld cladding is employed to improve the service life of engineering components by
increasing corrosion and wear resistance and reducing the cost. The acceptable multi-bead cladding layer depends on single bead geometry. Hence, in first step, the relationship between input process parameters and the single bead geometry is studied and in second step a comprehensive study on multi bead clad layer deposition is carried out. This paper highlights an experimental study carried out to get single layer cladding deposited by automated GMAW process and to find the possibility of hot forming of the cladded work piece to get the final hot formed improved structure. The experiments for single bead were conducted by varying the three main process parameters wire feed rate, arc voltage and welding speed while keeping other parameters like nozzle to work distance, shielding gas and its flow rate and torch angle constant. The effect of bead spacing and torch orientation on the cladding quality of single layer from the results of single bead deposition was studied. A hot bending test at different temperatures of cladded plates with different dilution and nominal energy carried out
Multiscale Modeling of Composites: Toward Virtual Testing ... and Beyond

Recent developments in the area of multiscale modeling of fiber-reinforced polymers are presented. The overall strategy takes advantage of the separa-tion of length scales between different entities (ply, laminate, and component) found in composite structures. This allows us to carry out multiscale modeling by computing the properties of one entity (e.g., individual plies) at the relevant length scale, homogenizing the results into a constitutive model, and passing this information to the next length scale to determine the mechanical behavior of the larger entity (e.g., laminate). As a result, high-fidelity numerical sim-ulations of the mechanical behavior of composite coupons and small compo-nents are nowadays feasible starting from the matrix, fiber, and interface properties and spatial distribution. Finally, the roadmap is outlined for extending the current strategy to include functional properties and processing into the simulation scheme
A Hierarchical Tracking Strategy for Vision-Based Applications On-Board UAVs

In this paper, we apply a hierarchical tracking strategy of planar objects (or that can be assumed to be planar) that is based on direct methods for vision-based applications on-board UAVs. The use of this tracking strategy allows to achieve the tasks at real-time frame rates and to overcome problems posed by the challenging conditions of the tasks: e.g. constant vibrations, fast 3D changes, or limited capacity on-board. The vast majority of approaches make use of feature-based methods to track objects. Nonetheless, in this paper we show that although some of these feature-based solutions are faster, direct methods can be more robust under fast 3D motions (fast changes in position), some changes in appearance, constant vibrations (without requiring any specific hardware or software for video stabilization), and situations in which part of the object to track is outside of the field of view of the camera. The performance of the proposed tracking strategy on-board UAVs is evaluated with images from realflight  tests using manually-generated ground truth information, accurate position estimation using a Vicon system, and also with simulated data from a simulation environment. Results show that the hierarchical tracking strategy performs better than wellknown feature-based algorithms and well-known configurations of direct methods, and that its performance is robust enough for vision-in-the-loop tasks, e.g. for vision-based landing tasks