323 research outputs found

    Perfect transfer of coherent state-based qubits via coupled cavities

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    Motivated by the need for communication of coherent state-based qubits in quantum computers, we introduce a method for perfect transferring of an arbitrary superposition of coherent states between two distant nodes of a linear array of three semiconductor QDs. The QDs trapped in a system of coupled cavities. In this method, the field mode of the cavities, as the resource of transferring of quantum states, are only virtually excited which minimizes the effect of decoherence due to photon loss.Comment: 10 pages, 3 figures. arXiv admin note: text overlap with arXiv:quant-ph/0211055 by other author

    Perfect routing of quantum information in regular cavity QED networks

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    We introduce a scheme for perfect routing of quantum states and entanglement in regular cavity QED networks. The couplings between the cavities are quasi-uniform and each cavity is doped with a two-level atom. Quasi-uniform couplings leads the system to evolve in invariant subspaces. Combination the evolutions of the system in its invariant subspaces with quite simple local operations on atoms in the networks, gives the perfect routing of quantum states and entanglement through the network. To provide the protocol be robust due to decoherence arisen from photon loss, the field mode of the cavities are only virtually excited

    Prediction of critical thinking disposition based on mentoring among faculty members

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    This study attempted to see if there is any relationship between Mentoring and  critical thinking disposition among faculty members and predict critical thinking disposition based on faculty members mentoring. The study population is all full-time faculty members of Isfahan University as 500 in academic year  2013-2014. To this end, a random sample of 217 faculty members was selected. The following scales were applied: critical thinking disposition (Ricketts, 2003) and Mentoring scale (Based on Anderson and Shannon mentoring principles, 1988) .The validity of scales was  computed with factor analysis by confirmatory method and alpha coefficients for  determining the reliability of each variable were as follows: Critical thinking disposition (α=.95) and Mentoring (α=.82). The results of study showed that there was a  significantly positive correlation between Mentoring and Critical thinking disposition among faculty members. The findings showed that 67% of variance of critical thinking disposition was defined by predictive variables. The faculty members evaluated themselves in all mentoring and critical thinking lower than desirable level.Keywords: Mentoring, Critical thinking disposition, Faculty member

    Two-qutrit Entanglement Witnesses and Gell-Mann Matrices

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    The Gell-Mann λ\lambda matrices for Lie algebra su(3) are the natural basis for the Hilbert space of Hermitian operators acting on the states of a three-level system(qutrit). So the construction of EWs for two-qutrit states by using these matrices may be an interesting problem. In this paper, several two-qutrit EWs are constructed based on the Gell-Mann matrices by using the linear programming (LP) method exactly or approximately. The decomposability and non-decomposability of constructed EWs are also discussed and it is shown that the λ\lambda-diagonal EWs presented in this paper are all decomposable but there exist non-decomposable ones among λ\lambda-non-diagonal EWs.Comment: 25 page

    Physical and mechanical properties of Oak (Quercus Persica) fruits

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    This research was conducted over one Iranian variety of Oak (Quercus Persica) with 70 observations. Physical and mechanical properties of oak are necessary for equipment used in activities such as transportation, storage, grading, packing etc. Properties which were measured include fruit dimensions, mass, volume, projected area, fruit density, geometric mean diameter, sphericity and surface area. Bulk density, porosity and also packing coefficient were measured. Experiments were carried out at Results showed that average mass and volume were 12.95 g and 10.27 mL, respectively. Dimensions increased from 41.85 to 61.09 mm in length, 14.45 to 25.02 mm in width and 14.42 to 24.38 mm in thickness. The mean projected area perpendicular to length, width and thickness obtained 433.91, 1085.48 and 1115.46 mm2, respectively. The geometric mean diameter and surface area were calculated as 27.638 mm and 2423.82 mm2, respectively, while sphericity was measured 51.78%. Elasticity modulus (E), maximum force which fruit can support (Fmax) and work which performed to this force have been determined

    Perspectives on the revised Ghent criteria for the diagnosis of Marfan syndrome

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    Three international nosologies have been proposed for the diagnosis of Marfan syndrome (MFS): the Berlin nosology in 1988; the Ghent nosology in 1996 (Ghent-1); and the revised Ghent nosology in 2010 (Ghent-2). We reviewed the literature and discussed the challenges and concepts of diagnosing MFS in adults. Ghent-1 proposed more stringent clinical criteria, which led to the confirmation of MFS in only 32%-53% of patients formerly diagnosed with MFS according to the Berlin nosology. Conversely, both the Ghent-1 and Ghent-2 nosologies diagnosed MFS, and both yielded similar frequencies of MFS in persons with a causative FBN1 mutation (90% for Ghent-1 versus 92% for Ghent-2) and in persons not having a causative FBN1 mutation (15% versus 13%). Quality criteria for diagnostic methods include objectivity, reliability, and validity. However, the nosology-based diagnosis of MFS lacks a diagnostic reference standard and, hence, quality criteria such as sensitivity, specificity, or accuracy cannot be assessed. Medical utility of diagnosis implies congruency with the historical criteria of MFS, as well as with information about the etiology, pathogenesis, diagnostic triggers, prognostic triggers, and potential complications of MFS. In addition, social and psychological utilities of diagnostic criteria include acceptance by patients, patient organizations, clinicians and scientists, practicability, costs, and the reduction of anxiety. Since the utility of a diagnosis or exclusion of MFS is context-dependent, prioritization of utilities is a strategic decision in the process of nosology development. Screening tests for MFS should be used to identify persons with MFS. To confirm the diagnosis of MFS, Ghent-1 and Ghent-2 perform similarly, but Ghent-2 is easier to use. To maximize the utility of the diagnostic criteria of MFS, a fair and transparent process of nosology development is essential

    The efficacy of time-based short-course acyclovir therapy in treatment of post-herpetic pain

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    Introduction: Various treatments have been used to manage post-herpetic neuralgia (PHN). Safe and effective therapies to prevent PHN are needed. Methodology: A clinical trial involving 152 patients diagnosed with acute herpes Zoster (HZ) was conducted to determine whether short-course acyclovir therapy (800 mg five times a day for four days) can alleviate HZ-associated pain and prevent post-herpetic neuralgia (PHN). The patients were divided into two groups: Group 1 had a rash with a duration of less than 72 hours and Group 2 had a rash with a duration of more than 72 hours. To assess PHN, the patients categorized and assessed the severity of their symptoms using a four-point verbal rating scale (VRS). Results: By the fourth week, 134 out of 152 patients (88.2) had complete pain response (CPR). Of these, 68 patients (89.5) were from Group 1 and 66 from Group 2 (86.8). After four weeks, the mean VRS scores had changed significantly in both groups compared to the scores at the beginning of study (p = 0.001), but there was no difference between the two groups (0.88 ± 0.66 Vs. 0.94 ± 0.72; p = 0.66) After three months no differences were observed in the treatment results between the two groups (0.51 ± 0.13 Vs.0.54 ± 0.19; p = 0.77). Conclusion: Short-course acyclovir therapy is an effective treatment for zoster and its efficacy in patients with a rash duration of more than 72 hours is similar to that in patients with rash duration of less than 72 hours. © 2010 Rasi et al

    Constructing Entanglement Witness Via Real Skew-Symmetric Operators

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    In this work, new types of EWs are introduced. They are constructed by using real skew-symmetric operators defined on a single party subsystem of a bipartite dxd system and a maximal entangled state in that system. A canonical form for these witnesses is proposed which is called canonical EW in corresponding to canonical real skew-symmetric operator. Also for each possible partition of the canonical real skew-symmetric operator corresponding EW is obtained. The method used for dxd case is extended to d1xd2 systems. It is shown that there exist Cd2xd1 distinct possibilities to construct EWs for a given d1xd2 Hilbert space. The optimality and nd-optimality problem is studied for each type of EWs. In each step, a large class of quantum PPT states is introduced. It is shown that among them there exist entangled PPT states which are detected by the constructed witnesses. Also the idea of canonical EWs is extended to obtain other EWs with greater PPT entanglement detection power.Comment: 40 page

    Deriving a multi-subject functional-connectivity atlas to inform connectome estimation

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    MICCAI 2014 preprintInternational audienceThe estimation of functional connectivity structure from functional neuroimaging data is an important step toward understanding the mechanisms of various brain diseases and building relevant biomarkers. Yet, such inferences have to deal with the low signal-to-noise ratio and the paucity of the data. With at our disposal a steadily growing volume of publicly available neuroimaging data, it is however possible to improve the estimation procedures involved in connectome mapping. In this work, we propose a novel learning scheme for functional connectivity based on sparse Gaussian graphical models that aims at minimizing the bias induced by the regularization used in the estimation, by carefully separating the estimation of the model support from the coefficients. Moreover, our strategy makes it possible to include new data with a limited computational cost. We illustrate the physiological relevance of the learned prior, that can be identified as a functional connectivity atlas, based on an experiment on 46 subjects of the Human Connectome Dataset
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