Dynamics of entanglement creation between two spins coupled to a chain

We study the dynamics of entanglement between two spins which is created by the coupling to a common thermal reservoir. The reservoir is a spin-$\frac{1}{2}$ Ising transverse field chain thermally excited, the two defect spins couple to two spins of the chain which can be at a macroscopic distance. In the weak-coupling and low-temperature limit the spin chain is mapped onto a bath of linearly interacting oscillators using the Holstein-Primakoff transformation. We analyse the time evolution of the density matrix of the two defect spins for transient times and deduce the entanglement which is generated by the common reservoir. We discuss several scenarios for different initial states of the two spins and for varying distances.Comment: 16 pages, 5 figure

Body and Interaction in Dematerialisation

In a world that seems to dematerialise and to digitalise gradually and steadily, it is crucial, and plausibly necessary, to understand the new elements that characterise the individuality and permanence of matter concerning the concept of virtuality as the next challenge for designers. The topic results highly relevant due to the constant progress of virtual reality technologies and cloud services, increasingly sophisticated and affordable for everyone. This progress generates new problems for the discussion for which no significant solutions exist yet

Entangling two defects via a surrounding crystal

We theoretically show how two impurity defects in a crystalline structure can be entangled through coupling with the crystal. We demonstrate this with a harmonic chain of trapped ions in which two ions of a different species are embedded. Entanglement is found for sufficiently cold chains and for a certain class of initial, separable states of the defects. It results from the interplay between localized modes which involve the defects and the interposed ions, it is independent of the chain size, and decays slowly with the distance between the impurities. These dynamics can be observed in systems exhibiting spatial order, viable realizations are optical lattices, optomechanical systems, or cavity arrays in circuit QED.Comment: 5 pages, 5 figure

Characterisation of Extracts Obtained from Unripe Grapes and Evaluation of Their Potential Protective Effects against Oxidation of Wine Colour in Comparison with Different Oenological Products

Unripe grapes (UGs) are a waste product of vine cultivation rich in natural antioxidants. These antioxidants could be used in winemaking as alternatives to SO(2). Three extracts were obtained by maceration from Viognier, Merlot and Sangiovese UGs. The composition and antioxidant activity of the UG extracts were studied in model solutions at different pH levels. The capacity of the UG extracts to protect wine colour was evaluated in accelerated oxidation tests and small-scale trials on both red and white wines during ageing in comparison with sulphur dioxide, ascorbic acid and commercial tannins. The Viognier and Merlot extracts were rich in phenolic acids while the Sangiovese extract was rich in flavonoids. The antioxidant activity of the extracts and commercial tannins was influenced by the pH. In the oxidation tests, the extracts and commercial products showed different wine colour protection capacities in function of the type of wine. During ageing, the white wine with the added Viognier UG extract showed the lowest level of colour oxidation. The colour of the red wine with the UG extract evolved similarly to wine with SO(2) and commercial tannins. The obtained results indicated that natural and healthy UG extracts could be an interesting substitute for SO(2) during wine ageing

A New Technique for Exploitation of Wine Lees

Abstract The possibility of obtaining high quality wine from lees could increase value added for farm productions. A new technique introduced on an industrial scale to provide wine from lees of different origin is presented. After racking, the lees are collected in an innovative steel system and processed in controlled conditions of temperature, micro-oxigenation and cycles of remixing. During the treatment, an increase of color intensity, total polyphenols and total polysaccharides of wine from the lees was detected while the hue was stable. The obtained results indicate that the proposed method could be an effective tool for exploitation of the lees on winery scale. The new technology strongly reduced the time necessary to reach positive oenological objectives

Hollow viscus injuries. Predictors of outcome and role of diagnostic delay

INTRODUCTION: Hollow viscus injuries (HVIs) are uncommon but potentially catastrophic conditions with high mortality and morbidity rates. The aim of this study was to analyze our 16-year experience with patients undergoing surgery for blunt or penetrating bowel trauma to identify prognostic factors with particular attention to the influence of diagnostic delay on outcome. METHODS: From our multicenter trauma registry, we selected 169 consecutive patients with an HVI, enrolled from 2000 to 2016. Preoperative, intraoperative, and postoperative data were analyzed to assess determinants of mortality, morbidity, and length of stay by univariate and multivariate analysis models. RESULTS: Overall mortality and morbidity rates were 15.9% and 36.1%, respectively. The mean length of hospital stay was 23±7 days. Morbidity was independently related to an increase of white blood cells (P=0.01), and to delay of treatment >6 hours (P=0.033), while Injury Severity Score (ISS) (P=0.01), presence of shock (P=0.01), and a low diastolic arterial pressure registered at emergency room admission (P=0.02) significantly affected postoperative mortality. CONCLUSION: There is evidence that patients with clinical signs of shock, low diastolic pressure at admission, and high ISS are at increased risk of postoperative mortality. Leukocytosis and delayed treatment (>6 hours) were independent predictors of postoperative morbidity. More effort should be made to increase the preoperative detection rate of HVI and reduce the delay of treatment

Chlorido(η 4-cyclo­octa-1,5-diene)(N,N′-diethyl­thio­urea-κS)rhodium(I)

In the title rhodium(I) complex, [RhCl(C8H12)(C5H12N2S)], N,N′-diethyl­thio­urea acts as a monodenate S-donor ligand. The rhodium(I) coordination sphere is completed by the Cl atom and the COD [= 1,5-cyclo­octa­diene] ligand inter­acting through the π-electrons of the double bonds. If the midpoints of these two bonds are taken into account, the Rh atom exhibits a distorted square-planar coordination. The syn conformation of the N,N′-diethyl­thio­urea ligand with respect to the Cl atom is stabilized by an intra­molecular N—H⋯Cl hydrogen bond. A weak inter­molecular N—H⋯Cl inter­action links mol­ecules along the a axis

Apparent stiffness of vimentin intermediate filaments in living cells and its relation with other cytoskeletal polymers

The cytoskeleton is a complex network of interconnected biopolymers intimately involved in the generation and transmission of forces. Several mechanical properties of microtubules and actin filaments have been extensively explored in cells. In contrast, intermediate filaments (IFs) received comparatively less attention despite their central role in defining cell shape, motility and adhesion during physiological processes as well as in tumor progression. Here, we explored relevant biophysical properties of vimentin IFs in living cells combining confocal microscopy and a filament tracking routine that allows localizing filaments with ~20 nm precision. A Fourier-based analysis showed that IFs curvatures followed a thermal-like behavior characterized by an apparent persistence length (lp*) similar to that measured in aqueous solution. Additionally, we determined that certain perturbations of the cytoskeleton affect lp* and the lateral mobility of IFs as assessed in cells in which either the microtubule dynamic instability was reduced or actin filaments were partially depolymerized. Our results provide relevant clues on how vimentin IFs mechanically couple with microtubules and actin filaments in cells and support a role of this network in the response to mechanical stress.Fil: Smoler, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Coceano, Giovanna. Royal Institute of Technology; SueciaFil: Testa, Ilaria. Royal Institute of Technology; SueciaFil: Bruno, Luciana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Calculo. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Calculo; ArgentinaFil: Levi, Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentin