A study of separability criteria for mixed three-qubit states

We study the noisy GHZ-W mixture. We demonstrate some necessary but not sufficient criteria for different classes of separability of these states. It turns out that the partial transposition criterion of Peres and the criteria of G\"uhne and Seevinck dealing with matrix elements are the strongest ones for different separability classes of this 2 parameter state. As a new result we determine a set of entangled states of positive partial transpose.Comment: 18 pages, 10 figures, PRA styl

On circulant states with positive partial transpose

We construct a large class of quantum "d x d" states which are positive under partial transposition (so called PPT states). The construction is based on certain direct sum decomposition of the total Hilbert space displaying characteristic circular structure - that is way we call them circulant states. It turns out that partial transposition maps any such decomposition into another one and hence both original density matrix and its partially transposed partner share similar cyclic properties. This class contains many well known examples of PPT states from the literature and gives rise to a huge family of completely new states.Comment: 15 pages; minor correction

Class of PPT bound entangled states associated to almost any set of pure entangled states

We analyze a class of entangled states for bipartite $d \otimes d$ systems, with $d$ non-prime. The entanglement of such states is revealed by the construction of canonically associated entanglement witnesses. The structure of the states is very simple and similar to the one of isotropic states: they are a mixture of a separable and a pure entangled state whose supports are orthogonal. Despite such simple structure, in an opportune interval of the mixing parameter their entanglement is not revealed by partial transposition nor by the realignment criterion, i.e. by any permutational criterion in the bipartite setting. In the range in which the states are Positive under Partial Transposition (PPT), they are not distillable; on the other hand, the states in the considered class are provably distillable as soon as they are Nonpositive under Partial Transposition (NPT). The states are associated to any set of more than two pure states. The analysis is extended to the multipartite setting. By an opportune selection of the set of multipartite pure states, it is possible to construct mixed states which are PPT with respect to any choice of bipartite cuts and nevertheless exhibit genuine multipartite entanglement. Finally, we show that every $k$-positive but not completely positive map is associated to a family of nondecomposable maps.Comment: 12 pages, 3 figures. To appear in Phys. Rev.

Extreme points of the set of density matrices with positive partial transpose

We present a necessary and sufficient condition for a finite dimensional density matrix to be an extreme point of the convex set of density matrices with positive partial transpose with respect to a subsystem. We also give an algorithm for finding such extreme points and illustrate this by some examples.Comment: 4 pages, 2 figure

Local Food Impacts on Health and Nutrition

Prevalence of local foods is believed to answer several food issues one of which is health and nutrition. This study focused on the on the availability of local foods to consumers and see its relationship with two specific diet-related diseases namely, obesity and diabetes. Other variables were included in the analysis to provide additional evidence to previous findings. Factors considered are divided into 5 groups namely diet-, local food-, environment-, education- and gender-related factors. Diet- and environment-related variables provide the most perceptive findings while local food variables provided significant however weak evidence of positive impacts to health and nutrition.local foods, diabetes, obesity, food environment, farmers' market, Agricultural and Food Policy, Consumer/Household Economics, Food Consumption/Nutrition/Food Safety, Health Economics and Policy, I15, I31,

Evaluating the structure and magnitude of the ash plume during the initial phase of the 2010 Eyjafjallajökull eruption using lidar observations and NAME simulations

The Eyjafjallajökull volcano in Iceland erupted explosively on 14 April 2010, emitting a plume of ash into the atmosphere. The ash was transported from Iceland toward Europe where mostly cloud-free skies allowed ground-based lidars at Chilbolton in England and Leipzig in Germany to estimate the mass concentration in the ash cloud as it passed overhead. The UK Met Office's Numerical Atmospheric-dispersion Modeling Environment (NAME) has been used to simulate the evolution of the ash cloud from the Eyjafjallajökull volcano during the initial phase of the ash emissions, 14–16 April 2010. NAME captures the timing and sloped structure of the ash layer observed over Leipzig, close to the central axis of the ash cloud. Relatively small errors in the ash cloud position, probably caused by the cumulative effect of errors in the driving meteorology en route, result in a timing error at distances far from the central axis of the ash cloud. Taking the timing error into account, NAME is able to capture the sloped ash layer over the UK. Comparison of the lidar observations and NAME simulations has allowed an estimation of the plume height time series to be made. It is necessary to include in the model input the large variations in plume height in order to accurately predict the ash cloud structure at long range. Quantitative comparison with the mass concentrations at Leipzig and Chilbolton suggest that around 3% of the total emitted mass is transported as far as these sites by small (<100 μm diameter) ash particles

Strategies for Fructo-oligosaccharides production with high-content and purity

Book of Abstracts of CEB Annual Meeting 2017[Excerpt] The consumers’ interest in healthy and high nutritional food has significantly increased in the recent years. This trend towards the adoption of healthier lifestyles has been the main driver for the great demand of functional ingredients, such as the prebiotics fructo-oligosaccharides (FOS). Industrially, FOS are produced from sucrose through purified enzymes, in two-step bioprocesses, with low theoretical yields (0.50-0.55 gFOS.gSucrose-1) and purities (50-55%). Downstream steps are therefore needed to remove the non-prebiotic sugars and enable the incorporation of these FOS mixtures in diabetic, dietetic and healthy foods. In the last ten years, we have been investigating new strategies to produce FOS with higher contents, purities and differentiated functionalities. We have been exploring Aureobasidium pullulans and Aspergillus ibericus as FOS producers, in one-step fermentation processes, using the whole cells of the microorganisms instead of the isolated enzymes. This strategy proved to be efficient, fast and economic, yielding 0.64 gFOS.gSucrose-1. The FOS mixtures produced were able to stimulate the growth of probiotic strains and were simultaneously resistant to hydrolysis along the gastrointestinal system confirming their health claims as prebiotics. The probiotic strains preferentially metabolized the FOS mixture synthesized by A. ibericus, followed by the one from A. pullulans and lastly the commercial FOS. [...]info:eu-repo/semantics/publishedVersio

Fructo-oligosaccharides: production, characterization and purification

GLUPOR 12 - 12nd International Meeting of the Portuguese Carbohydrate Chemistry GroupThe consumers interest in healthy and high nutritional food has significantly increased in the recent years. This trend towards the adoption of healthier lifestyles has been the main driver for the great demand of functional ingredients, such as the prebiotics fructo-oligosaccharides (FOS). Industrially, FOS are produced from sucrose through purified enzymes, in two-step bioprocesses, with low theoretical yields (0.50-0.55 gFOS.gSucrose-1) and purities (50-55%). Downstream steps are therefore needed to remove the non-prebiotic sugars and enable the incorporation of these FOS mixtures in diabetic, dietetic and healthy foods. In the last ten years, we have been investigating new strategies to produce FOS with higher contents, purities and differentiated functionalities. We have been exploring Aureobasidium pullulans and Aspergillus ibericus as FOS producers, in one-step fermentation processes, using the whole cells of the microorganisms instead of the isolated enzymes. This strategy proved to be efficient, fast and economic, yielding 0.64 gFOS.gSucrose-1. The FOS mixtures produced were able to stimulate the growth of probiotic strains and were simultaneously resistant to hydrolysis along the gastrointestinal system confirming their health claims as prebiotics. The probiotic strains preferentially metabolized the FOS mixture synthesized by A. ibericus, followed by the one from A. pullulans and lastly the commercial FOS. The purification of FOS is not straightforward due to the physicochemical similarities between the different oligosaccharides and the smaller saccharides. To increase the FOS purity, we have been exploring different strategies including microbial treatments and downstream treatments as activated charcoal and ion-exchange chromatography. As microbial treatments, we studied the use of a Saccharomyces cerevisiae strain, able to metabolize the small saccharides without FOS hydrolyse, in co-culture with the FOS microorganism producer or in a two-step fermentation, in which FOS are firstly synthesized and then purified by the S. cerevisiae. Fermentations in two-steps were found to be more efficient than the co-culture ones and purities of 82% (w/w) in FOS were obtained [1]. To avoid competition by the subtract in the co-culture, we are now evaluating the use of a S. cerevisiae strain with the SUC2 gene for invertase expression repressed. Using this strategy, FOS are being produced with yields of 0.64 gFOS.gSucrose-1 and purities up to 93% (w/w). As downstream treatment we optimized an adsorption/desorption process of sugars using activated charcoal and ethanol as eluent. Mixtures containing 50.6% (w/w) of FOS were purified to 92.9% (w/w) with a FOS recovery of 74.5% (w/w) and some fractions were obtained with purities up to 97% (w/w) [2]. Acknowledgements: Clarisse Nobre acknowledges the Portuguese Foundation for Science and Technology (FCT) for her Post-Doc Grant [ref. SFRH/BPD/87498/2012] and the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462), the strategic funding of UID/BIO/04469/2013 unit, COMPETE 2020 (POCI-01-0145-FEDER-006684), BioTecNorte operation (NORTE-01-0145-FEDER-000004) and the project MultiBiorefinery (POCI-01-0145-FEDER-016403) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. References [1] Nobre, C, Castro, CC, Hantson, A-L, Teixeira, JA, Weireld, G, Rodrigues, LR, Strategies for the production of high-content fructo-oligosaccharides through the removal of small saccharides by co-culture or successive fermentation with yeast, Carbohydrate Polymers, 136, 274281, 2016. [2] Nobre, C, Teixeira, JA, Rodrigues, LR, Fructo-oligosaccharides purification from a fermentative broth using an activated charcoal column. New Biotechnology, 29(3), 395401, 2012.Clarisse Nobre acknowledges the Portuguese Foundation for Science and Technology (FCT) for her Post-Doc Grant [ref. SFRH/BPD/87498/2012] and the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER027462), the strategic funding of UID/BIO/04469/2013 unit, COMPETE 2020 (POCI-01-0145-FEDER-006684), BioTecNorte operation (NORTE-01-0145-FEDER-000004) and the project MultiBiorefinery (POCI-01-0145-FEDER016403) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

An Ethical Inquiry to Personhood as the Standard for Sexbot Ownership: A Response to S. Petersen

In the field of robot ethics, debates about sexbots, their personhood, and their moral status continue. To provide our stance in this debate, we ask the question: Is it unethical for sexbots to be owned? This paper responds to the claims of Steve Petersen’s (2016) paper “Is it good for them too? Ethical concerns for the sexbots”, where he argues that sexbots are not wronged for performing the functions they are designed for. We respond to this claim by arguing for John Danaher’s Theory of Ethical Behaviorism (2020). If ethical behaviorism is correct in claiming that behavior is a sufficient ground for moral status ascription, we see sexbot ownership as unethical. We argue for our claim and show that the moral considerability of the sexbot could be proven under the standards given in our framework for ascribing moral status

Schmidt balls around the identity

Robustness measures as introduced by Vidal and Tarrach [PRA, 59, 141-155] quantify the extent to which entangled states remain entangled under mixing. Analogously, we introduce here the Schmidt robustness and the random Schmidt robustness. The latter notion is closely related to the construction of Schmidt balls around the identity. We analyse the situation for pure states and provide non-trivial upper and lower bounds. Upper bounds to the random Schmidt-2 robustness allow us to construct a particularly simple distillability criterion. We present two conjectures, the first one is related to the radius of inner balls around the identity in the convex set of Schmidt number n-states. We also conjecture a class of optimal Schmidt witnesses for pure states.Comment: 7 pages, 1 figur