Effects of Medial Prefrontal Cortical Administration of the Orexin-2 Receptor Antagonist, TCS-OX2-29, on Attentional Performance in Rats

Orexins are excitatory neuropeptides that come in two isoforms, Orexin A and Orexin B, and serve as ligands for the G-protein coupled orexin 1 and orexin 2 receptors (Ox1R and Ox2R, respectively). Changes in orexinergic transmission are thought to contribute to attentional processing. While several studies have examined the role of Ox1Rs in attention, less research has assessed the contribution of Ox2Rs. Moreover, several lines of evidence suggest that the right medial prefrontal cortex is particularly critical for visual attentional performance. Taking all of this into consideration, the goal of the present experiment was to test the effects Ox2R blockade, via administration of TCS-OX2-29, in the left or right medial prefrontal cortex on visual attention. The results suggest that low dose administration of TCS-OX2-29 into the right, but not into the left, medial prefrontal cortex enhanced attentional performance. We speculate that relatively mild antagonism of Ox2Rs may have increased the sensitivity of these receptors to subsequent orexin transmission, thereby enhancing attentional performance. Ongoing projects in our laboratory are assessing whether these effects are observed when TCS-OX2-29 is infused into other brain regions known to be critical for attentional performance

Political Theatre in Public Spaces: Manifesting Identity in Venice, Italy

The combination of poorly managed mass tourism, rapidly increasing international migration, and a declining economy facilitated a permanent exodus of natives out of the Venetian lagoon. This thesis examines how the community activism group and social network Venessia.com attempts to reclaim a place-­based and place-­manifested Venetian identity (venezianità) through theatrical public protests. While members are sensitive to an ethic of intercultural awareness, the discourse accompanying their concerns reveals nostalgia for the power and grandeur of Venice’s past that is threatened by a perceived invasion by suspicious outsiders. The theoretical framework I employ to illuminate Venessia.com\u27s efforts includes the socio-­cultural and economic implications of mass tourism, theory of space and place, and critiques of modernity and postmodernity

A limit on nonlocality in any world in which communication complexity is not trivial

Bell proved that quantum entanglement enables two space-like separated parties to exhibit classically impossible correlations. Even though these correlations are stronger than anything classically achievable, they cannot be harnessed to make instantaneous (faster than light) communication possible. Yet, Popescu and Rohrlich have shown that even stronger correlations can be defined, under which instantaneous communication remains impossible. This raises the question: Why are the correlations achievable by quantum mechanics not maximal among those that preserve causality? We give a partial answer to this question by showing that slightly stronger correlations would result in a world in which communication complexity becomes trivial.Comment: 13 pages, no figure

First-Principles Study for the Anisotropy of Iron-based Superconductors toward Power and Device Applications

Performing the first-principles calculations, we investigate the anisotropy in the superconducting state of iron-based superconductors to gain an insight into their potential applications. The anisotropy ratio $\gamma_\lambda$ of the c-axis penetration depth to the ab-plane one is relatively small in BaFe2As2 and LiFeAs, i.e., $\gamma_\lambda \sim 3$, indicating that the transport applications are promising in these superconductors. On the other hand, in those having perovskite type blocking layers such as Sr2ScFePO3 we find a very large value, $\gamma_\lambda \sim 200$, comparable to that in strongly anisotropic high-Tc cuprate Bi2Sr2CaCu2O{8-\delta}. Thus, the intrinsic Josephson junction stacks are expected to be formed along the c-axis, and novel Josephson effects due to the multi-gap nature are also suggested in these superconductors.Comment: 5 pages, 4 figure

Optimality of private quantum channels

We addressed the question of optimality of private quantum channels. We have shown that the Shannon entropy of the classical key necessary to securely transfer the quantum information is lower bounded by the entropy exchange of the private quantum channel $\cal E$ and von Neumann entropy of the ciphertext state $\varrho^{(0)}$. Based on these bounds we have shown that decomposition of private quantum channels into orthogonal unitaries (if exists) is optimizing the entropy. For non-ancillary single qubit PQC we have derived the optimal entropy for arbitrary set of plaintexts. In particular, we have shown that except when the (closure of the) set of plaintexts contains all states, one bit key is sufficient. We characterized and analyzed all the possible single qubit private quantum channels for arbitrary set of plaintexts. For the set of plaintexts consisting of all qubit states we have characterized all possible approximate private quantum channels and we have derived the relation between the security parameter and the corresponding minimal entropy.Comment: no commen

Private quantum decoupling and secure disposal of information

Given a bipartite system, correlations between its subsystems can be understood as information that each one carries about the other. In order to give a model-independent description of secure information disposal, we propose the paradigm of private quantum decoupling, corresponding to locally reducing correlations in a given bipartite quantum state without transferring them to the environment. In this framework, the concept of private local randomness naturally arises as a resource, and total correlations get divided into eliminable and ineliminable ones. We prove upper and lower bounds on the amount of ineliminable correlations present in an arbitrary bipartite state, and show that, in tripartite pure states, ineliminable correlations satisfy a monogamy constraint, making apparent their quantum nature. A relation with entanglement theory is provided by showing that ineliminable correlations constitute an entanglement parameter. In the limit of infinitely many copies of the initial state provided, we compute the regularized ineliminable correlations to be measured by the coherent information, which is thus equipped with a new operational interpretation. In particular, our results imply that two subsystems can be privately decoupled if their joint state is separable.Comment: Child of 0807.3594 v2: minor changes v3: presentation improved, one figure added v4: extended version with a lot of discussions and examples v5: published versio

Non-adaptive Measurement-based Quantum Computation and Multi-party Bell Inequalities

Quantum correlations exhibit behaviour that cannot be resolved with a local hidden variable picture of the world. In quantum information, they are also used as resources for information processing tasks, such as Measurement-based Quantum Computation (MQC). In MQC, universal quantum computation can be achieved via adaptive measurements on a suitable entangled resource state. In this paper, we look at a version of MQC in which we remove the adaptivity of measurements and aim to understand what computational abilities still remain in the resource. We show that there are explicit connections between this model of computation and the question of non-classicality in quantum correlations. We demonstrate this by focussing on deterministic computation of Boolean functions, in which natural generalisations of the Greenberger-Horne-Zeilinger (GHZ) paradox emerge; we then explore probabilistic computation, via which multipartite Bell Inequalities can be defined. We use this correspondence to define families of multi-party Bell inequalities, which we show to have a number of interesting contrasting properties.Comment: 13 pages, 4 figures, final version accepted for publicatio

Some Directions beyond Traditional Quantum Secret Sharing

We investigate two directions beyond the traditional quantum secret sharing (QSS). First, a restriction on QSS that comes from the no-cloning theorem is that any pair of authorized sets in an access structure should overlap. From the viewpoint of application, this places an unnatural constraint on secret sharing. We present a generalization, called assisted QSS (AQSS), where access structures without pairwise overlap of authorized sets is permissible, provided some shares are withheld by the share dealer. We show that no more than $\lambda-1$ withheld shares are required, where $\lambda$ is the minimum number of {\em partially linked classes} among the authorized sets for the QSS. Our result means that such applications of QSS need not be thwarted by the no-cloning theorem. Secondly, we point out a way of combining the features of QSS and quantum key distribution (QKD) for applications where a classical information is shared by quantum means. We observe that in such case, it is often possible to reduce the security proof of QSS to that of QKD.Comment: To appear in Physica Scripta, 7 pages, 1 figure, subsumes arXiv:quant-ph/040720