Proximal Fifth Metatarsal Fractures: Anatomy, Classification, Treatment and Complications

Context: Fractures of proximal fifth metatarsal are one of the most common fractures of the foot. Evidence Acquisition: A search of PubMed for studies on proximal fifth metatarsal fracture and Jones fracture focusing on the classification and management was performed. The reference list of the retrieved articles was searched for additional related studies. Results: The vascular supply and soft tissue anatomy of the fifth metatarsal explains the increased risk of delayed union and non-union in fractures at the metaphyseal-diaphyseal junction. Lawrence and Botte classify proximal fifth metatarsal fractures according to their location: tuberosity avulsion fractures (zone 1), fractures at metaphyseal-diaphyseal junction extending into the fourth-fifth intermetatarsal joint (zone 2) and proximal diaphyseal fractures (zone 3). Zone 1 fractures are treated conservatively with functional immobilization and early mobilization with excellent outcome. For zone 2 and zone 3 fractures, acute forms can be treated conservatively but with a risk of delayed union time and time for return to function. Therefore, early surgical fixation with intramedullary screw is advised in athletic individuals. For cases presented with signs of delayed union and non-union, surgical treatment with or without bone grafting is recommended. Complications of these fractures and their management are discussed in this report. Conclusions: Lawrence and Botte’s classification of proximal fifth metatarsal fractures is recommended by experts, due to its implication on prognosis and treatment strategy. Zone 1 fractures should be treated conservatively due to their excellent healing potential. Early operative treatment is advised for zone 2 and zone 3 fractures, especially in the athletic group. Complications of delayed union, non-union and refractures should be treated by revision fixation and bone grafting

The 25 October 2010 Mentawai tsunami earthquake (M_w 7.8) and the tsunami hazard presented by shallow megathrust ruptures

The 25 October 2010 Mentawai, Indonesia earthquake (M_w 7.8) ruptured the shallow portion of the subduction zone seaward of the Mentawai islands, off-shore of Sumatra, generating 3 to 9 m tsunami run-up along southwestern coasts of the Pagai Islands that took at least 431 lives. Analyses of teleseismic P, SH and Rayleigh waves for finite-fault source rupture characteristics indicate ∼90 s rupture duration with a low rupture velocity of ∼1.5 km/s on the 10° dipping megathrust, with total slip of 2–4 m over an ∼100 km long source region. The seismic moment-scaled energy release is 1.4 × 10^(−6), lower than 2.4 × 10^(−6) found for the 17 July 2006 Java tsunami earthquake (M_w 7.8). The Mentawai event ruptured up-dip of the slip region of the 12 September 2007 Kepulauan earthquake (M_w 7.9), and together with the 4 January 1907 (M 7.6) tsunami earthquake located seaward of Simeulue Island to the northwest along the arc, demonstrates the significant tsunami generation potential for shallow megathrust ruptures in regions up-dip of great underthrusting events in Indonesia and elsewhere

Towards the Application of Classification Techniques to Test and Identify Faults in Multimedia Systems

The advances in computer and graphic technologies have led to the popular use of multimedia for information exchange. However, multimedia systems are difficult to test. A major reason is that these systems generally exhibit fuzziness in their temporal behaviors. The fuzziness may be caused by the existence of non-deterministic factors in their runtime environments, such as system load and network traffic. It complicates the analysis of test results. The problem is aggravated when a test involves the synchronization of different multimedia streams as well as variations in system loading.\ud \ud In this paper, we conduct an empirical study on the testing and fault-identification of multimedia systems by treating the issue as a classification problem. Typical classification techniques, including Bayesian networks, k-nearest neighbor, and neural networks, are experimented with the use of X-Smiles, an open sourced multimedia authoring tool supporting the Synchronized Multimedia Integration Language (SMIL). From these experiments, we make a few interesting observations and give plausible explanations based on the geometrical properties of the test results

Statistical Transfer Matrix Study of the ±J\pm J Multileg Ising Ladders and Tubes

Finite temperature properties of symmetric $\pm J$ multileg Ising ladders and tubes are investigated using the statistical transfer matrix method. The temperature dependences of the specific heat and entropy are calculated. In the case of tubes, it is found that the ground state entropy shows an even-odd oscillation with respect to the number of legs. The same type of oscillation is also found in the ground state energy. On the contrary, these oscillations do not take place in ladders. From the temperature-dependence of the specific heat, it is found that the lowest excitation energy is 4J for even-leg ladders while it is 2J otherwise, The physical origin of these behaviors is discussed based on the structure of excitations.Comment: 6 pages, 9 figure

Controlled Quantum Secret Sharing

We present a new protocol in which a secret multiqubit quantum state $\ket{\Psi}$ is shared by $n$ players and $m$ controllers, where $\ket{\Psi}$ is the encoding state of a quantum secret sharing scheme. The players may be considered as field agents responsible for carrying out a task, using the secret information encrypted in $\ket{\Psi}$, while the controllers are superiors who decide if and when the task should be carried out and who to do it. Our protocol only requires ancillary Bell states and Bell-basis measurements.Comment: 6 pages, 0 figure, RevTeX4; published version with minor change

Fermi-LAT and Suzaku Observations of the Radio Galaxy Centaurus B

Centaurus B is a nearby radio galaxy positioned in the Southern hemisphere close to the Galactic plane. Here we present a detailed analysis of about 43 months of accumulated Fermi-LAT data of the gamma-ray counterpart of the source initially reported in the 2nd Fermi-LAT catalog, and of newly acquired Suzaku X-ray data. We confirm its detection at GeV photon energies, and analyze the extension and variability of the gamma-ray source in the LAT dataset, in which it appears as a steady gamma-ray emitter. The X-ray core of Centaurus B is detected as a bright source of a continuum radiation. We do not detect however any diffuse X-ray emission from the known radio lobes, with the provided upper limit only marginally consistent with the previously claimed ASCA flux. Two scenarios that connect the X-ray and gamma-ray properties are considered. In the first one, we assume that the diffuse non-thermal X-ray emission component is not significantly below the derived Suzaku upper limit. In this case, modeling the inverse-Compton emission shows that the observed gamma-ray flux of the source may in principle be produced within the lobes. This association would imply that efficient in-situ acceleration of the radiating electrons is occurring and that the lobes are dominated by the pressure from the relativistic particles. In the second scenario, with the diffuse X-ray emission well below the Suzaku upper limits, the lobes in the system are instead dominated by the magnetic pressure. In this case, the observed gamma-ray flux is not likely to be produced within the lobes, but instead within the nuclear parts of the jet. By means of synchrotron self-Compton modeling we show that this possibility could be consistent with the broad-band data collected for the unresolved core of Centaurus B, including the newly derived Suzaku spectrum.Comment: Accepted for publication in A&A. 11 page

Discovery of an unidentified Fermi object as a black widow-like millisecond pulsar

The Fermi Gamma-ray Space Telescope has revolutionized our knowledge of the gamma-ray pulsar population, leading to the discovery of almost 100 gamma-ray pulsars and dozens of gamma-ray millisecond pulsars (MSPs). Although the outer-gap model predicts different sites of emission for the radio and gamma-ray pulsars, until now all of the known gamma-ray MSPs have been visible in the radio. Here we report the discovery of a "radio-quiet" gamma-ray emitting MSP candidate by using Fermi, Chandra, Swift, and optical observations. The X-ray and gamma-ray properties of the source are consistent with known gamma-ray pulsars. We also found a 4.63-hr orbital period in optical and X-ray data. We suggest that the source is a black widow-like MSP with a ~0.1 solar-mass late-type companion star. Based on the profile of the optical and X-ray light-curves, the companion star is believed to be heated by the pulsar while the X-ray emissions originate from pulsar magnetosphere and/or from intra-binary shock. No radio detection of the source has been reported yet and although no gamma-ray/radio pulsation has been found, we estimated that the spin period of the MSP is ~3-5 ms based on the inferred gamma-ray luminosity.Comment: 6 pages, 2 figures; accepted for publication in ApJ

Unparticle physics and lepton flavor violating radion decays in the Randall-Sundrum scenario

We predict the branching ratios of the lepton flavor violating radion decays r -> e^{\pm} \mu^{\pm}, r -> e^{\pm} \tau^{\pm} and r ->\mu^{\pm} \tau^{\pm} in the framework of the Randall-Sundrum scenario that the lepton flavor violation is carried by the scalar unparticle mediation. We observe that their BRs are strongly sensitive to the unparticle scaling dimension and, for its small values, the branching ratios can reach to the values of the order of 10^{-8}, for the heavy lepton flavor case.Comment: 21 pages, 11 Figures, 1 Tabl