pinecone/core-2020-05-10-deduplication huggingface dataset:
A reconfigurable wheelchair for mobility and rehabilitation: Design and development

This paper presents the design and development of a prototype of a reconfigurable wheelchair for rehabilitation and self-assistance to fit the size of a seven years old child (average 35 kg weight). Though the developed prototype is developed at this stage to fit a child, it can be resized, after considering variations in weight and size, to fit an older adult. The developed prototype has a mechanism that enables the user to transform from sit-to-stand (STS) posture and vice versa. With the help of the developed wheelchair, the user will also be able to adjust the posture of his upper body using an adjustable back support using two linear actuators. This configuration will allow the user to use the wheelchair as a mobility device as well as for rehabilitation purposes without the need of external support. The availability of STS and back adjustment mechanisms will allow the user to do regular exercising which will enhance blood circulation as sitting for long periods inflates lower limbs disability. The proposed configuration will help in enhancing the functional capabilities of end-users allowing for increased independence and ultimately quality of life
Electrical performance of carbon nanotube-polymer composites at frequencies up to 220 GHz

We have measured the sub-THz electrical response of screen printed carbon nanotube-poly(methyl methacrylate) polymer composites up to 220 GHz. The measured electrical losses using mm long coplanar waveguide geometries averaged as low as 0.15 dB/mm in the frequency range 40 GHz–110 GHz and showed a reduction in signal loss with increasing frequency; a behaviour opposite to that found in conventional metallic conductors. Between 140 and 220 GHz, the electrical losses averaged 0.28 dB/mm. We show that the low electrical losses are associated with the capacitive coupling between the nanotubes and discuss potential high frequency applications
Cyanuric Acid/Epichlorohydrin Energetic Prepolymers

In this work new energetic prepolymers are synthesised and characterised. The structure of the prepolymers exhibits the 1,3,5-s-triazine ring with lateral chains derived from the epichlorohydrin ring opening. The chlorine atoms in these precursors are here substituted by azido groups. The presence of these groups was confirmed by FTIR and 1H NMR spectroscopy and elemental and thermal analysis. OH group content in the energetic prepolymers was found slightly lower than expected having in view the used inert precursors, while molar mass values were similar. Whereas the precursors show an endothermic thermal decomposition, the synthesised prepolymers show a clear exothermic thermal decomposition in DSC analyses. Due to the presence of the 1,3,5-s-triazine ring, the exothermic peaks were observed in a wide range of temperatures. The measured glass transition temperatures vary from -15.5 °C to -43.3 °C. High densities and a wide range of viscosities were found.http://dx.doi.org/10.1002/prep.20050002
The faunal role in the degradation of the common intertidal salt marsh plant Scirpus maritimus

Abstract  The aim of this work was to evaluate the role of different environmental conditions (oxic and anoxic), and the presence of macrofauna and/or meiofauna during the different steps of Scirpus maritimus L. decomposition/mineralization under controlled laboratory conditions. The results showed no significant differences between the anaerobic and the aerobic degradation of plant material, under the presence of bacteria or meiofauna. Nevertheless, under anoxic conditions sediment mineralization was enhanced, with an increase concentration of phosphorus and ammonium in the water phase. Concerning the presence of fauna, results show that, although bacterial activity was responsible for 70% of the S. maritimus leaves degradation, the presence of macrofauna together with meiofauna enhanced the leaves mineralization up to 90%. Moreover, the presence of macrofauna together with meiofauna significantly affected the decomposition of phosphorus and of nitrogen, as well as the leaves lesser labile structural parts, by increasing the mineralization of plant carbon, and raised the nutrient turnover within the system.The present study reinforces the functional link between fauna levels on the nutrient dynamics in salt marshes ecosystems, namely at the vegetation detritus/water column interface.http://dx.doi.org/10.1007/s10750-006-0535-
Spin-orbit torques in Co/Pt(111) and Mn/W(001) magnetic bilayers from
  first principles

An applied electric current through a space-inversion asymmetric magnet
induces spin-orbit torques (SOTs) on the magnetic moments, which holds much
promise for future memory devices. We discuss general Green's function
expressions suitable to compute the linear-response SOT in disordered
ferromagnets. The SOT can be decomposed into an even and an odd component with
respect to magnetization reversal, where in the limit of vanishing disorder the
even SOT is given by the constant Berry curvature of the occupied states, while
the odd part exhibits a divergence with respect to disorder strength. Within
this formalism, we perform first principles density-functional theory
calculations of the SOT in Co/Pt(111) and Mn/W(001) magnetic bilayers. We find
the even and odd torque components to be of comparable magnitude. Moreover, the
odd torque depends strongly on an additional capping layer, while the even
torque is less sensitive. We show that the even torque is nearly entirely
mediated by spin currents in contrast to the odd torque, which can contain an
important contribution not due to spin transfer. Our results are in agreement
with experiments, showing that our linear response theory is well-suited for
the description of SOTs in complex ferromagnets
Landau-Lifshitz sigma-models, fermions and the AdS/CFT correspondence

We define Landau-Lifshitz sigma models on general coset space $G/H$, with $H$ a maximal stability sub-group of $G$. These are non-relativistic models that have $G$-valued N\"other charges, local $H$ invariance and are classically integrable. Using this definition, we construct the $PSU(2,2|4)/PS(U(2|2)^2)$ Landau-Lifshitz sigma-model. This sigma model describes the thermodynamic limit of the spin-chain Hamiltonian obtained from the complete one-loop dilatation operator of the N=4 super Yang-Mills (SYM) theory. In the second part of the paper, we identify a number of consistent truncations of the Type IIB Green-Schwarz action on $AdS_5\times S^5$ whose field content consists of two real bosons and 4,8 or 16 real fermions. We show that $\kappa$-symmetry acts trivially in these sub-sectors. In the context of the large spin limit of the AdS/CFT correspondence, we map the Lagrangians of these sub-sectors to corresponding truncations of the $PSU(2,2|4)/PS(U(2|2)^2)$ Landau-Lifshitz sigma-model
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
Self-consistent relativistic band structure of the CH3NH3PbI3 perovskite

The electronic structure and properties of the orthorhombic phase of the CH 3 NH 3 PbI 3   perovskite are computed with density functional theory. The structure, optimized using a van der Waals functional, reproduces closely the unit cell volume. The experimental band gap is reproduced accurately by combining spin-orbit effects and a hybrid functional in which the fraction of exact exchange is tuned self-consistently to the optical dielectric constant. Including spin-orbit coupling strongly reduces the anisotropy of the effective mass tensor, predicting a low electron effective mass in all crystal directions. The computed binding energy of the unrelaxed exciton agrees with experimental data, and the values found imply a fast exciton dissociation at ambient temperature. Also polaron masses for the separated carriers are estimated. The values of all these parameters agree with recent indications that fast dynamics and large carrier diffusion lengths are key in the high photovoltaic efficiencies shown by these materials
Three's company when seeking unanimity

Random searches are routinely used in many algorithms, for instance, when looking for the shortest path connecting 100 cities or for ordering genomes in a most-parsimonious descendency tree. In this issue of PNAS, Matsen and Nowak use a random search for another type of problem, that of finding coherence rather than optimality. The task thus consists of reaching unanimity. The proposed solution is outrageously simple: Keep switching until you agree with two others, then stop. Under a wide set of conditions, this slapdash recipe works
Variation in cognitive functioning as a refined approach to comparing aging across countries

Comparing the burden of aging across countries hinges on the availability of valid and comparable indicators. The Old Age Dependency Ratio allows only a limited assessment of the challenges of aging, because it does not include information on any individual characteristics except age itself. Existing alternative indicators based on health or economic activity suffer from measurement and comparability problems. We propose an indicator based on age variation in cognitive functioning. We use newly released data from standardized tests of seniors' cognitive abilities for countries from different world regions. In the wake of long-term advances in countries industrial composition, and technological advances, the ability to handle new job procedures is now of high and growing importance, which increases the importance of cognition for work performance over time. In several countries with older populations, we find better cognitive performance on the part of populations aged 50+ than in countries with chronologically younger populations. This variation in cognitive functioning levels may be explained by the fact that seniors in some regions of the world experienced better conditions during childhood and adult life, including nutrition, duration and quality of schooling, lower exposure to disease, and physical and social activity patterns. Because of the slow process of cohort replacement, those countries whose seniors already have higher cognitive levels today are likely to continue to be at an advantage for several decades to come
The method of regions and next-to-soft corrections in Drell–Yan production

We perform a case study of the behaviour of gluon radiation beyond the soft approximation, using as an example the Drell–Yan production cross section at NNLO. We draw a careful distinction between the eikonal expansion, which is in powers of the soft gluon energies, and the expansion in powers of the threshold variable 1−z , which involves important hard-collinear effects. Focusing on the contribution to the NNLO Drell–Yan K-factor arising from real–virtual interference, we use the method of regions to classify all relevant contributions up to next-to-leading power in the threshold expansion. With this method, we reproduce the exact two-loop result to the required accuracy, including z -independent non-logarithmic contributions, and we precisely identify the origin of the soft-collinear interference which breaks simple soft-gluon factorisation at next-to-eikonal level. Our results pave the way for the development of a general factorisation formula for next-to-leading-power threshold logarithms, and clarify the nature of loop corrections to a set of recently proposed next-to-soft theorems
A minimal supersymmetric E 6 unified theory

We show explicitly that supersymmetric E 6 Grand Unified Theory with a Higgs sector consisting of 27 + 27 ¯ + 351 ′ + 351 ′ ¯ + 78 $$ \left\{27 + \overline{27} + {351}^{\prime } + {\overline{351}}^{\prime } + 78\right\} $$ fields provides a realistic scenario for symmetry breaking and fermion mass generation. While gauge symmetry breaking can be achieved without the 78 field, its presence is critical for a successful doublet-triplet mass splitting. The Yukawa sector of the model consists of only two symmetric matrices describing all of quark, lepton and neutrino masses and mixings. The fermion mass matrices are computed at low energy and a fit to the second and third generation masses and mixings is performed. We find a good numerical fit to the low-energy data. Thus, this model, having 11 superpotential parameters, alongside the two symmetric Yukawa matrices, seems to be the best realistic candidate for a minimal renormalizable supersymmetric E 6 unified theory
Super-PINGU for measurement of the leptonic CP-phase with atmospheric neutrinos

We explore a possibility to measure the CP-violating phase δ using multimegaton scale ice or water Cherenkov detectors with low, (0.2-1) GeV, energy threshold assuming that the neutrino mass hierarchy is identified. We elaborate the relevant theoretical and phenomenological aspects of this possibility. The distributions of the ν μ (track) and ν e (cascade) events in the neutrino energy and zenith angle ( E ν − θ z ) plane have been computed for different values of δ . We study properties and distinguishability of the distributions before and after smearing over the neutrino energy and zenith angle. The CP-violation effects are not washed out by smearing, and furthermore, the sensitivity to δ increases with decrease of the energy threshold. The ν e events contribute to the CP-sensitivity as much as the ν μ events. While sensitivity of PINGU to δ is low, we find that future possible upgrade, Super-PINGU, with few megaton effective volume at (0 . 5-1) GeV and e.g. after 4 years of exposure will be able to disentangle values of δ = π/ 2 , π, 3 π/ 2 from δ = 0 with “distinguishability” (∼ significance in σ’s) S σ tot  = (3 − 8), (6 − 14), (3 − 8) correspondingly. Here the intervals of S σot are due to various uncertainties of detection of the low energy events, especially the flavor identification, systematics, etc. Super-PINGU can be used simultaneously for the proton decay searches
Compatible abelian symmetries in N-Higgs-doublet models

We analyze the compatibility between abelian symmetries acting in two different sectors of a theory using the Smith Normal Form method. We focus on N-Higgs-doublet models (NHDMs) and on the compatibility between symmetries in the Higgs potential and in the Yukawa interactions, which were separately analyzed in previous works. It is shown that two equal (isomorphic) symmetry groups that act in two separate sectors are not necessarily compatible in the whole theory and an upper bound is found for the size of the group that can be implemented in the entire NHDM. We also develop useful techniques to analyze compatibility and extend a symmetry from one sector to another. Consequences to the supersymmetric case are briefly discussed
Static and radiating p -form black holes in the higher dimensional Robinson-Trautman class

We study Robinson-Trautman spacetimes in the presence of an aligned p -form Maxwell field and an arbitrary cosmological constant in n ≥ 4 dimensions. As it turns out, the character of these exact solutions depends significantly on the (relative) value of n and p . In odd dimensions the solutions reduce to static black holes dressed with an electric and a magnetic field, with an Einstein space horizon (further constrained by the Einstein-Maxwell equations) — both the Weyl and Maxwell types are D. Even dimensions, however, open up more possibilities. In particular, when 2 p = n there exist non-static solutions describing black holes gaining (or losing) mass by receiving (or emitting) electromagnetic radiation. In this case the Weyl type is II (D) and the Maxwell type can be II (D) or N. Conditions under which the Maxwell field is self-dual (for odd p ) are also discussed, and a few explicit examples presented. Finally, the case p = 1 is special in all dimensions and leads to static metrics with a non-Einstein transverse space
Supersymmetry and cotangent bundle over non-compact exceptional Hermitian symmetric space

We construct N = 2 $$ \mathcal{N}=2 $$ supersymmetric nonlinear sigma models on the cotangent bundles over the non-compact exceptional Hermitian symmetric spaces ℳ = E 6 − 14 / SO 10 × U 1 $$ \mathrm{\mathcal{M}}={E}_{6\left(-14\right)}/\mathrm{SO}(10)\times \mathrm{U}(1) $$ and E 7(−25) /E 6 × U(1). In order to construct them we use the projective superspace formalism which is an N = 2 $$ \mathcal{N}=2 $$ off-shell superfield formulation in four-dimensional space-time. This formalism allows us to obtain the explicit expression of N = 2 $$ \mathcal{N}=2 $$ supersymmetric nonlinear sigma models on the cotangent bundles over any Hermitian symmetric spaces in terms of the N = 1 $$ \mathcal{N}=1 $$ superfields, once the Kähler potentials of the base manifolds are obtained. We derive the N = 1 $$ \mathcal{N}=1 $$ supersymmetric nonlinear sigma models on the Kähler manifolds ℳ $$ \mathrm{\mathcal{M}} $$ . Then we extend them into the N = 2 $$ \mathcal{N}=2 $$ supersymmetric models with the use of the result in arXiv:1211.1537 developed in the projective superspace formalism. The resultant models are the N = 2 $$ \mathcal{N}=2 $$ supersymmetric nonlinear sigma models on the cotangent bundles over the Hermitian symmetric spaces ℳ $$ \mathrm{\mathcal{M}} $$ . In this work we complete constructing the cotangent bundles over all the compact and non-compact Hermitian symmetric spaces
Monte Carlo and event-driven dynamics of Brownian particles with orientational degrees of freedom

Recently, a simple scaling argument was introduced that allows us to map, with some precautions, Brownian and Monte Carlo dynamics for spherical particles. Here, we extend the scaling to study systems that have orientational degrees of freedom and carefully asses its validity over a wide region of temperature and density. Our work allows us to devise a Brownian Monte Carlo algorithm that produces, to a good approximation, physically meaningful trajectories with a minimum programming effort, although at the expense of some sampling efficiency
Temperature of solar cells with regard to photoactive and non-photoactive light absorption in concentrator PV modules

A new method has recently been proposed by us for accurate measurement of the solar cell temperature in any operational regime, in particular, at a maximum power point (MPP) of the I-V curve (T-p-n(MPP)). For this, fast switching of a cell from MPP to open circuit (OC) regime is carried out and open circuit voltage V-oc is measured immediately (within about 1 millisecond), so that this value becomes to be an indicator of T-p-n(MPP). In the present work, we have considered a practical case, when a solar cell is heated not only by absorption of light incident upon its surface (called "photoactive" absorption of power), but also by heat transferred from structural elements surrounding the cell and heated by absorption of direct or diffused sunlight ("non-photoactive" absorption of power with respect to a solar cell). This process takes place in any concentrator module with non-ideal concentrators. Low overheating temperature of the p-n junction (or p-n junctions in a multijunction cell) is a cumulative parameter characterizing the quality of a solar module by the factor of heat removal effectiveness and, at the same time, by the factor of low "non-photoactive" losses
Composite Leptoquarks at the LHC

If electroweak symmetry breaking arises via strongly-coupled physics, the observed suppression of flavour-changing processes suggests that fermion masses should arise via mixing of elementary fermions with composite fermions of the strong sector. The strong sector then carries colour charge, and may contain composite leptoquark states, arising either as TeV scale resonances, or even as light, pseudo-Nambu-Goldstone bosons. The latter, since they are coupled to colour, get a mass of the order of several hundred GeV, beyond the reach of current searches at the Tevatron. The same generic mechanism that suppresses flavour-changing processes suppresses leptoquark-mediated rare processes, making it conceivable that the many stringent constraints may be evaded. The leptoquarks couple predominantly to third-generation quarks and leptons, and the prospects for discovery at LHC appear to be good. As an illustration, a model based on the Pati-Salam symmetry is described, and its embedding in models with a larger symmetry incorporating unification of gauge couplings, which provide additional motivation for leptoquark states at or below the TeV scale, is discussed
External Learning Opportunities and the Diffusion of Process Innovations to Small Firms: The Case of Programmable Automation

In this chapter, we are concerned with explaining which types of firms have failed to adopt well-known improvements in process technology. This problem has, of course, been the underlying concern of all studies of diffusion “to rationalize why, if a new technology is superior, it is not taken up by all potential adopters” (Stoneman, 1983). Drawing on various theoretical perspectives, we identify a number of different barriers to adoption. With data collected from a 1987 nationally representative sample of US establishments in 21 metal-working and machinery manufacturing industries, we then construct a multivariate logistic regression model to empirically test for the effects of these factors on the likelihood of adoption of a particular process innovation, namely programmable automation (PA) machine tools
The Construction of a Clinical Decision Support System Based on Knowledge Base

Part 7: e-Health, the New Frontier of Service Science InnovationInternational audienceBased on a review of domestic and foreign research, application status, classification, composition, and the main problem of a clinical decision support system, this paper proposed a CDSS mode based on a knowledge base. On KB-CDSS mode, this paper discussed the architecture, principle, process, construction of the knowledge base, system design, and application value, then introduced the application WanFang Data Clinical Diagnosis and Treatment Knowledge Base