TWO RECIPES FROM PORTUGUESE TRADITION OF GILDING ON WOODEN SUPPORT BETWEEN LABORATORY REPRODUCTION AND ANALYTICAL INVESTIGATION

This paper has the main purpose to compile and highlight the first data obtained from experimental studies on docμmented reconstructions of gilded composites performed within a research project on gilding materials and techniques in Portugal (www.gilt-teller.pt) funded by FCT. Two water gilding recipes were appropriately chosen from the treatises written by the Portuguese Filipe Nunes (1615) and José Lopes Baptista de Almada (1749) as being representative for Baroque époque. Based on these recipes, the production of raw materials - “gesso grosso”, “gesso fino”, bole, animal glue (from lamb and goat skins) - was made as faithful as possible. Their application was then performed in laboratory following the indications given by these authors or by treatises of previous époques (e.g. the Bolognese treatise for thawing leather), on plane and curved wooden supports (pine and oak species) using three types of leaf: gold (Au/Ag/Cu) of 22 and 23.75 karat respectively and silver. After the completion of gilding, the samples’ surfaces were divided into areas and on each different finishing layers (wax, animal glue size) and decorations (punching, “esgrafitado”, “estofado”) were applied. An analytical campaign using optical microscopy (OM) and scanning electron microscopy (SEM) on surfaces and cross sections, X-ray diffraction (XRD), microcomputerized tomography (microCT) and colorimetry (CIEL*a*b*) was undertaken in order to characterize the gilded composites and to assess the faithfulness of the reproductions in the laboratory. Correlations between the information given by the recipes and the composition and stratigraphical patterns of the reconstructions can be established. Furthermore, the study aims to highlight the difficulties encountered in analyzing real samples and comparing the results with those from reproductions as the number and types of layered materials are not always reproducible. A critical approach is needed and criteria for faithful reproduction of ancient recipes are suggested

From Things to Services: A Social IoT Approach for Tourist Service Management

In the context of Internet of Things (IoT), the cooperation and synergy between varied and disparate communicating objects is strained by trustworthiness, confidentiality and interoperability concerns. These restrictions can limit the development of IoT-based applications especially considering the emergent boost in the number of communicating objects and their growing itinerant nature in a collective service context. A new perspective arises with the paradigm of Social Internet of Things (SIoT), that relies on the implementation of semi-independent communicating objects with cooperation assessed by social relations and social feed-back. In this article, we present the development and expansion of the IoT concept towards SIoT in the context of the interactions between tourist services as communicating objects. As a proof-of-concept we propose a composition of services as virtualized social objects and the interaction between them, by taking into consideration the balance, trustworthiness, cooperation and synergy of services. Furthermore we present a solution to integrate also accessibility in SIoT services. The presented concept is presented using a demonstrator build for tourist services

Purification of Noisy Entanglement and Faithful Teleportation via Noisy Channels

Two separated observers, by applying local operations to a supply of not-too-impure entangled states ({\em e.g.} singlets shared through a noisy channel), can prepare a smaller number of entangled pairs of arbitrarily high purity ({\em e.g.} near-perfect singlets). These can then be used to faithfully teleport unknown quantum states from one observer to the other, thereby achieving faithful transfrom one observer to the other, thereby achieving faithful transmission of quantum information through a noisy channel. We give upper and lower bounds on the yield $D(M)$ of pure singlets ($\ket{\Psi^-}$) distillable from mixed states $M$, showing $D(M)>0$ if \bra{\Psi^-}M\ket{\Psi^-}>\half.Comment: 4 pages (revtex) plus 1 figure (postscript). See also http://vesta.physics.ucla.edu/~smolin/ . Replaced to correct interchanged $\sigma_x$ and $\sigma_z$ near top of column 2, page

Uncertainty in the Representation of Orography in Weather and Climate Models and Implications for Parameterized Drag

The representation of orographic drag remains a major source of uncertainty for numerical weather prediction (NWP) and climate models. Its accuracy depends on contributions from both the model grid‐scale orography (GSO) and the subgrid‐scale orography (SSO). Different models use different source orography datasets and different methodologies to derive these orography fields. This study presents the first comparison of orography fields across several operational global NWP models. It also investigates the sensitivity of an orographic drag parameterisation to the inter‐model spread in SSO fields and the resulting implications for representing the northern hemisphere winter circulation in a NWP model. The inter‐model spread in both the GSO and the SSO fields is found to be considerable. This is due to differences in the underlying source dataset employed and in the manner in which this dataset is processed (in particular how it is smoothed and interpolated) to generate the model fields. The sensitivity of parameterised orographic drag to the inter‐model variability in SSO fields is shown to be considerable and dominated by the influence of two SSO fields: the standard deviation and the mean gradient of the SSO. NWP model sensitivity experiments demonstrate that the inter‐model spread in these fields is of first‐order importance to the inter‐model spread in parameterised surface stress, and to current known systematic model biases. The revealed importance of the SSO fields supports careful reconsideration of how these fields are generated, guiding future development of orographic drag parameterisations and re‐evaluation of the resolved impacts of orography on the flow

Enhancement of de Haas-van Alphen Oscillation due to Spin in the Magnetic Breakdown System

The effects of the Zeeman term on the de Haas-van Alphen oscillation is studied in the magnetic breakdown system. We find that the amplitude of the oscillation with the frequencies of $f_{\beta} + f_{\alpha}$ and $f_{\beta} + 2f_{\alpha}$ are enhanced by the Zeeman term, while they are expected to be reduced in the semiclassical theory. A possible interpretation of the experiments in organic conductors is discussed.Comment: 4 pages,4 figures. Submitted to Journal of Physical Society of Japa

Motional effects on the efficiency of excitation transfer

Energy transfer plays a vital role in many natural and technological processes. In this work, we study the effects of mechanical motion on the excitation transfer through a chain of interacting molecules with application to biological scenarios of transfer processes. Our investigation demonstrates that, for various types of mechanical oscillations, the transfer efficiency is significantly enhanced over that of comparable static configurations. This enhancement is a genuine quantum signature, and requires the collaborative interplay between the quantum-coherent evolution of the excitation and the mechanical motion of the molecules; it has no analogue in the classical incoherent energy transfer. This effect may not only occur naturally, but it could be exploited in artificially designed systems to optimize transport processes. As an application, we discuss a simple and hence robust control technique.Comment: 25 pages, 11 figures; completely revised; version accepted for publicatio

The foundations of statistical mechanics from entanglement: Individual states vs. averages

We consider an alternative approach to the foundations of statistical mechanics, in which subjective randomness, ensemble-averaging or time-averaging are not required. Instead, the universe (i.e. the system together with a sufficiently large environment) is in a quantum pure state subject to a global constraint, and thermalisation results from entanglement between system and environment. We formulate and prove a "General Canonical Principle", which states that the system will be thermalised for almost all pure states of the universe, and provide rigorous quantitative bounds using Levy's Lemma.Comment: 12 pages, v3 title changed, v2 minor change