Conservation law for distributed entanglement of formation and quantum discord

We present a direct relation, based upon a monogamic principle, between entanglement of formation (EOF) and quantum discord (QD), showing how they are distributed in an arbitrary tripartite pure system. By extending it to a paradigmatic situation of a bipartite system coupled to an environment, we demonstrate that the EOF and the QD obey a conservation relation. By means of this relation we show that in the deterministic quantum computer with one pure qubit the protocol has the ability to rearrange the EOF and the QD, which implies that quantum computation can be understood on a different basis as a coherent dynamics where quantum correlations are distributed between the qubits of the computer. Furthermore, for a tripartite mixed state we show that the balance between distributed EOF and QD results in a stronger version of the strong subadditivity of entropy.Comment: Published versio

Expression and functional analysis of rat P23, a gut hormone-inducible isoform of trypsin, reveals its resistance to proteinaceous trypsin inhibitors

AbstractRat P23 is an isoform of trypsin (ogens) synthesized by rat acinar cells. Expression of P23 is stimulated strongly by caerulein, an analogue of cholecystokinin (CCK). However, the physiological relevance of rat P23 in healthy and pathological conditions such as caerulein-induced pancreatitis is largely unknown. Using recombinant P23 trypsinogen and reconstitution analysis of zymogen autoactivation, unique inhibitor-resistance characteristics of P23 were elucidated. P23 cDNA was expressed in Escherichia coli periplasm, yielding recombinant P23 trypsinogen. Autoactivation of zymogen granule contents from caerulein-induced rat pancreas was also studied. Activation kinetics of P23 by enterokinase was similar to those of rat anionic trypsinogen, which is a major isoform of trypsinogen. Interestingly, rat pancreatic secretory trypsin inhibitor (PSTI), which protects against deleterious activation of trypsinogens in zymogen granules, failed to inhibit P23 trypsin even with four-fold molar excess, at which concentration it effectively inhibited rat anionic trypsin to almost 100%. P23 trypsin also showed marked resistance to proteinaceous trypsin inhibitors such as soybean trypsin inhibitor and aprotinin. P23 trypsin activated by enterokinase dramatically accelerated the cascade of autoactivation of anionic trypsinogen even in the presence of PSTI. Taken together with a previous observation that P23 is specifically upregulated 14-fold by 24-h caerulein infusion, these results suggest that elevated levels of P23 should be taken into consideration in the mechanism of trypsinogens within the pancreas in pathological conditions

“Sweet: I did it”! Measuring the sense of agency in gustatory interfaces

Novel gustatory interfaces offer the potential to use the sense of taste as a feedback modality during the interaction. They are being explored in a wide range of implementations, from chemical to electrical and thermal stimulation of taste. However, the fundamental aspect of gustatory interaction that has yet to be explored is the Sense of Agency (SoA). It is the subjective experience of voluntary control over actions in the external world. This work investigates the SoA in gustatory systems using the intentional binding paradigm to quantify how different taste outcome modalities influence users' SoA. We first investigate such gustatory systems using the intentional binding paradigm to quantify how different tastes influence users' SoA (Experiment 1). The gustatory stimuli were sweet (sucrose 75.31 mg/ml), bitter (caffeine powder 0.97 mg/ml), and neutral (mineral water) as the outcomes of specific keyboard presses. We then investigated how SoA was altered depending on users' sweet liking phenotype, given that sweet is one of the taste outcomes (Experiment 2), and in contrast with audio as a traditional outcome. In Experiment 2, stronger taste concentrations (sweet-sucrose 342.30 g/L, bitter-quinine 0.1 g/L, and neutral) were used, with only participants being moderate sweet likers. We further contrasted tastes with audio as the traditional outcome. Our findings show that all three taste outcomes exhibit similar intentional binding compared to auditory in medium sweet likers. We also show that longer action-outcome duration improved the SoA. We finally discuss our findings and identify design opportunities considering SoA for gustatory interfaces and multisensory interaction

Environment-induced anisotropy and sensitivity of the radical pair mechanism in the avian compass

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOSeveral experiments over the years have shown that the earth's magnetic field is essential for orientation in birds' migration. The most promising explanation for this orientation is the photo-stimulated radical pair (RP) mechanism. In order to define a reference frame for the orientation task radicals must have an intrinsic anisotropy. We show that this kind of anisotropy and consequently the entanglement in the model are not necessary for the proper functioning of the compass. Classically correlated initial conditions for the RP, subjected to a fast decoherence process, are able to provide the anisotropy required. Even a dephasing environment can provide the necessary frame for the compass to work and also implies fast decay of any quantum correlation in the system without damaging the orientation ability. This fact significantly expands the range of applicability of the RP mechanism providing more elements for experimental search.Several experiments over the years have shown that the earth's magnetic field is essential for orientation in birds' migration. The most promising explanation for this orientation is the photo-stimulated radical pair (RP) mechanism. In order to define a reference frame for the orientation task radicals must have an intrinsic anisotropy. We show that this kind of anisotropy and consequently the entanglement in the model are not necessary for the proper functioning of the compass. Classically correlated initial conditions for the RP, subjected to a fast decoherence process, are able to provide the anisotropy required. Even a dephasing environment can provide the necessary frame for the compass to work and also implies fast decay of any quantum correlation in the system without damaging the orientation ability. This fact significantly expands the range of applicability of the RP mechanism providing more elements for experimental search.92116FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOSem informaçãoSem informaçãoWe thank M. Plenio and P. Hore for important comments and helpful discussion on our model. This work is supported by the Brazilian funding agencies CNPq and FAPESP through the Instituto Nacional de Ciência e Tecnologia–Informação Quântica (INCT-IQ). M.C.O. wishes to thank the hospitality of the Institute for Quantum Information Science at the University of Calgary, where part of this work was developed

HOMO AND COPOLYMERIZATION OF OLEFINS AND CYCLO-OLEFINS BY HOMOGENEOUS METALLOCENE AND HALF-METALLOCENE CATALYSTS

Propene copolymers by homogeneous metallocenes form a new class of thermoplastic elastomers with lower melting points, lower glass transition temperatures and higher impact strength than stereoregular polypropene (PP). The copolymerization of propene with ethene is a common way of tailoring the density and crystallinity of propene based polymers and thus to obtain a material that is more elastic than iPP or sPP homopolymer. The introduction of metallocenes in copolymerization reactions has also created new opportunities for the synthesis of olefin copolymers with uniform compositions and random sequence distributions and with tailored microstructures and properties. The molecular weight control is an important issue for accessing the practical production of polymeric materials. Indeed, both for Cs-symmetric and C2-symmetric catalysts it was found that the Mw of ethene-propene copolymers are in general lower than those of propene homopolymers. Incorporation of a substituent at the 3 position of the cyclopentadienyl ring of bridged (C5H4)(C13H8)MCl2 (M = Ti, Zr, Hf) with Cs symmetry induces desymmetrization of the metallocene to C1 symmetry. The microstructure of propene homopolymers using C1-symmetric metallocenes greatly depends on the nature and hindrance of the substituent on Cp group. When the substituent is a Me or i-Pr group, a hemi-isotactic or atactic polypropene is obtained; when the substituent is the bulkier t-Bu substituent, isotactic polypropene is achieved. These systems are amenable to study fine details of the polymerization mechanism. The mechanism which leads to the isotactic polypropene with C1-symmetric Me2C (3 ter butyl C5H3)(C13H8)MCl2 has been a topic of debate. For this reason a number of complex C1-symmetric metallocenes have been synthesized and studied recently. The aim of this part of the project on propene polymerization catalysis with C1-symmetric fluorenyl-containing metallocenes bearing one or two t Bu substituents at the 3 position of Cp or at 3 position of the fluorenyl groups. The main objective of this investigation was: to assess the impact of these changes on the polymerization mechanism and on catalytic performances for obtaining isotactic polypropene with high molar masses; to identify among the C1 symmetric catalysts those most promising for obtaining copolymers with high molar masses, as well as to give a rationale to such possibility. The effect of one or two ter-butyl substitutions on the catalytic activity, on the stereoerrors, and on molar masses in conditions which tend to approach those used in industrial processes was evaluated. Thus, C1-symmetric metallocenes were subjected to MAO-cocatalyzed propene homopolymerizations at different temperatures and monomer concentrations. Stereoerrors were investigated by 13C-NMR analysis. Observed polymer tacticity has been compared to that predicted by three statistical models: the first is enantiomorphic site control, which is predicted by the site epimerization mechanism, since it employs a single site with enantioselectivity \u3b1. The second is an alternating model that is generally applicable to a catalyst that regularly alternates insertions between a perfectly stereoselective site (\u3b1 = 1) and a variably stereo selective site having a stereoselectivity equal to \u3b2. The third is an alternating model that is applicable to a catalyst that regularly alternates insertions between two variably stereoselective sites. The stereoselectivity of one site is \u3b1, and the stereoselectivity of the other site is \u3b2. Both alternating models assume that no site epimerization is occurring. An analysis of chain end groups by 1H-NMR was performed in order to understand the role of substituents on polymer molar masses. Finally, the industrial synthesis of homo- and copolymers by homogeneous catalysts has to be achieved by supported systems in liquid propene because homogeneous processes present serious drawbacks such as reactor fouling as well as morphological issues. Thus, we have made efforts, at a laboratory scale, to study the variables that need to be controlled in order to produce reproducible polymers. The second part of the thesis concerned about cyclo-olefin copolymers. COP are a family of plastic materials derived from the polymerization of strained-ring monomers, with linear olefins, which generally exhibit unique physical and mechanical properties that differ from those of polyolefins with acyclic structures. Ethene(E)-co-Norbornene(N) copolymers are the most versatile and studied copolymers, because of their important end uses. (E-co-N)s are amorphous materials with a wide range of glass transition temperatures, ranging from r.t. to 220 \ub0C, depending on polymer composition, the higher the norbornene content, the higher is the percentage of norbornene diads and triads, and the higher is the Tg; they show excellent transparency and high refractive index because of their rigid bicyclic monomer units and high chemical resistance and are suitable for many applications such as coatings for high-capacity CDs and DVDs, for lenses, medical equipments, blisters, toner binder, and packaging. A promising approach to further expand the properties of COCs is the introduction of a third monomer like a linear \u3b1 12olefin such as 1- octene or the substitution of the bicyclic norbornane unit with a cyclopentane unit by 1,5-hexadiene cyclopolymerization. The presence of a long linear \u3b1-olefin or that of a cyclopentane unit into E-N copolymer backbone could increase the flexibility of the copolymer chain and improve the commercial applicability of the material, while maintaining a high transparency and the other characteristic properties of E-N copolymers. The catalytic performances of nonbridged half-titanocenes initially in E/N copolymerizations, then in E/N/HED terpolymerizations, and in E/N/O terpolymerizations, were investigated. Priority was to synthesize terpolymers that meet industrial requirements; therefore the synthesis have been conducted at conditions as close as possible to those used in industrial plants, that is temperature: 60 \ub0C and 4 bar ethene pressure. For all the three half-titanocenes, the addition of 1,5-hexadiene seems to negatively affect the activity, that results to be much lower with respect to the activity in E/N copolymerizations. The terpolymers have been characterized by 13C-NMR spectroscopy; the main objective was to determine the polymer composition in terms of norbornene and 1,5-hexadiene content. Especially at high norbornene content, the terpolymers obtained give rise to particularly complicated spectra and the peak assignment is very difficult; the chemical shifts of norbornene cyclic units result to be fairly similar to those ascribed to cyclopentane units. When the N content in the terpolymers is high, an overlapping between E/N backbone resonances and the major part of signals attributed to cyclopentane units, as well as the shifting of some other peaks, is reasonable to happen. As a consequence, to give unambiguous assignment of the CP structure peaks, a preliminary study of 13C-NMR spectra of N/HED and E/HED copolymers as function of feed composition has been performed. Since the introduction of a termonomer with a linear alkyl chain may allow to modulate the COC properties the synthesis of poly(E-ter-N-ter-O) by nonbridged half titanocenes was investigated. Terpolymerizations were carried out in a lab-scale autoclave under conditions as close as possible to those used in industrial plants, that is at high ethene pressure (4 bar) and high polymerization temperature (60 \ub0C). The terpolymers obtained were characterized by 13C-NMR to determine the polymer compositions, by SEC to determine the molar masses and molar mass distributions and by DSC to determine the glass transition temperatures. The preliminary data obtained are reported. The terpolymers have been synthesized at quite high N content to achieve synthesis of terpolymers with at least 30 N mol %, and thus Tgs higher than 70 \ub0C. [N]/[E] was fixed to 4/1 and just one 1- octene composition has been investigated. Very low amount of poly(E-ter-N-ter-O) has been obtained with all the catalytic systems. Under these experimental conditions the addition of 1- octene lowers notably the activity, showing depressed values for all the catalytic systems. All the terpolymers prepared have been characterized by 13C-NMR spectroscopy to determine the molar composition; the spectra exhibit the presence of signals characteristic of 1-octene units, even if, at high N content, an overlapping between E-N backbone resonances and 1-octene signals is revealed

Prevalence and awareness of type 2 diabetes mellitus among adult population in Mwanza city, Tanzania

Type 2 diabetes mellitus (T2DM) prevalence is increasing rapidly around the world. This cross-sectional study was conducted to assess the prevalence and awareness of type 2 diabetes mellitus in Mwanza city, Tanzania. A multistage random sampling technique was used to obtain representative subjects. Information about causes and risk factors were collected using structured questionnaire. In addition, community random blood glucose testing was employed to identify those at risk. Subjects with ≥200mg/dl on the following day were subjected to fasting blood glucose testing and they were confirmed to have T2DM if they had blood glucose level of ≥126mg/dl. In each subject, height, weight, waist and hip circumferences and total fat and fat free mass were measured using standard procedures. A total of 640 participants were included in this study, 55% were females and 45% were males. Mean age of the respondent was 43.84 ± 10.80 years. Most (46.4%) respondents were in the age group 30-40 years. Mean age for females was 44.0 ± 10.31 years while for males was 43.6 ± 11.3 years (Table 1). Overall prevalence of T2DM was 11.9%, (n=76). Prevalence was high in females (7.2%; n=46) than in males (4.7%; n=30). The age between 41-50 years had the highest prevalence of T2DM 28.6% followed by 51-60 years age group (17.2%). Significant independent associations were found for age (OR 3.88, 95% CI: 2.16-6.95) positive first degree relative with T2DM (OR 1.34; 95%C: 1.10-1.64) alcohol intake (OR 1.23; 95%CI: 1.02-1.48,) smoking (OR 3.86; 95%CI: 2.57-5.78) and hypertension (OR 0.096; 95%CI: 1.954-18.251). Only 49.2 (n=315) of the respondents knew about the causes and symptoms of T2DM. Public education on T2DM should be emphasized and routine measurement of blood glucose levels is recommended among adults

Thermal quantum and classical correlations in two qubit XX model in a nonuniform external magnetic field

We investigate how thermal quantum discord (QD) and classical correlations (CC) of a two-qubit one-dimensional XX Heisenberg chain in thermal equilibrium depend on the temperature of the bath as well as on nonuniform external magnetic fields applied to two qubits and varied separately. We show that the behavior of QD differs in many unexpected ways from the thermal entanglement (EOF). For the nonuniform case (B1 = -B2), we find that QD and CC are equal for all values of (B1 = -B2) and for different temperatures. We show that, in this case, the thermal states of the system belong to a class of mixed states and satisfy certain conditions under which QD and CC are equal. The specification of this class and the corresponding conditions are completely general and apply to any quantum system in a state in this class satisfying these conditions. We further find that the relative contributions of QD and CC can be controlled easily by changing the relative magnitudes of B1 and B2. Finally, we connect our results with the monogamy relations between the EOF, CC and the QD of two qubits and the environment.Comment: 8 pages, 13 figures. We connect our results with the monogamy relations between the EOF, CC and the QD of two qubits and the environmen

Annulus fibrosus functional extrafibrillar and fibrous mechanical behaviour: experimental and computational characterisation

The development of current surgical treatments for intervertebral disc damage could benefit from virtual environment accounting for population variations. For such models to be reliable, a relevant description of the mechanical properties of the different tissues and their role in the functional mechanics of the disc is of major importance. The aims of this work were first to assess the physiological hoop strain in the annulus fibrosus in fresh conditions (n = 5) in order to extract a functional behaviour of the extrafibrillar matrix; then to reverse-engineer the annulus fibrosus fibrillar behaviour (n = 6). This was achieved by performing both direct and global controlled calibration of material parameters, accounting for the whole process of experimental design and in silico model methodology. Direct-controlled models are specimen-specific models representing controlled experimental conditions that can be replicated and directly comparing measurements. Validation was performed on another six specimens and a sensitivity study was performed. Hoop strains were measured as 17 ± 3% after 10 min relaxation and 21 ± 4% after 20–25 min relaxation, with no significant difference between the two measurements. The extrafibrillar matrix functional moduli were measured as 1.5 ± 0.7 MPa. Fibre-related material parameters showed large variability, with a variance above 0.28. Direct-controlled calibration and validation provides confidence that the model development methodology can capture the measurable variation within the population of tested specimens