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Quantum logical states and operators for Josephson-like systems
No full textWe give a formal algebraic description of Josephson-type quantum dynamical systems, i.e., Hamiltonian systems with a cos -like potential term. The two-boson Heisenberg algebra plays for such systems the role that the h(1) algebra does for the harmonic oscillator. A single Josephson junction is selected as a representative of Josephson systems. We construct both logical states (codewords) and logical (gate) operators in the superconductive regime. The codewords are the even and odd coherent states of the two-boson algebra: they are shift-resistant and robust, due to squeezing. The logical operators acting on the qubit codewords are expressed in terms of operators in the enveloping of the two-boson algebra. Such a scheme appears to be relevant for quantum information applications
Clauser-Horne inequality for electron-counting statistics in multiterminal mesoscopic conductors
No full textRare shear-type fracture of the talar head in a thirteen-year-old child — Is this a transitional fracture: A case report and review of the literature
No full textBACKGROUND Talar fractures are exceedingly rare in childhood. There are very few studies on the clinical aspects, the long-term outcomes and the appropriate treatment of these fractures in pediatric patients. The mechanism of trauma consists of the application of a sudden dorsiflexion force on a fully plantar-flexed foot. Traumatic mechanism, symptoms and imaging of injuries of the talar head are similar to transitional fractures that are normally described at the distal epiphysis of the tibia: the so-called transitional fracture is defined as an epiphyseal injury when the growth plate has already started to close. CASE SUMMARY A thirteen-year-old girl reported a high-energy trauma to her right foot, due to falling from her horse. X-rays at the Emergency Department were negative. Because of persistent pain, the patient was assessed by an orthopedic surgeon after two weeks and computed tomography scans revealed a misdiagnosed displaced shear-type fracture of the talar head. Hence, surgical open reduction and fixation with two headless screws was performed. The girl was assessed regularly, and plain films at follow-up revealed complete healing of the fracture. Within six months after surgery, the patient returned to pre-injury sport activities reporting no complications. CONCLUSION Injuries of the talar head in childhood should be considered as transitional fractures. Open reduction with internal fixation aims to reduce malalignment and osteoarthritis. Computed tomography scans are recommended in these cases
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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