Sample records for super-shear rupture propagation

  1. Identification of Necessary Conditions for Super-shear Wave Rupture Speeds: The San Andreas Fault (United States)

    Das, S.


    The 2001 Kunlun, Tibet earthquake taught us that the portion of a strike-slip fault most likely to propagate at super-shear speeds are the long straight portions. This is only a necessary (but not sufficient) condition. That is, once a fault accelerates to the maximum permissible speed, it can continue at this speed provided it is straight and there are no obstacles along the way, and provided the fault friction is low. For the Tibet earthquake, the 100 km region of highest rupture speed also had the highest slip rate, the highest slip and the highest stress drop (Robinson et al., JGR, 2006). Off-fault cracks due to the passage of the Mach cone exists in only that portion of the fault identified as travelling at super-shear speed and not in other places along the fault (Bhat et al., JGR, 2007). Re-examination of earlier reports of super-shear rupture speeds on the North Anatolian fault and the Denali fault show that such speeds did occur on the straight section of these faults. Of course all straight portions of faults will not reach super-shear speeds. So what can the Tibet earthquake teach us about the San Andreas fault? Both the 1906 and the 1857 have long, straight portions, the former having been identified by Song et al. (EOS, 2005) as having reached super-shear speeds to the north of San Francisco, the region of highest slip. If the repeat of the 1857 starts in the central valley, as it is believed to have done in 1857, it has the potential to propagate at super-shear speeds through the long, straight portion of the San Andread fault in the Carrizo Plain, the region believed to have had the largest displacement in 1857 based on paleoseismic studies. The resulting shock waves would strike the highly populated regions of Santa Barbara and the Los Angeles Basin (Das, Science, 2007).

  2. Pseudodynamic Source Characterization for Strike-Slip Faulting Including Stress Heterogeneity and Super-Shear Ruptures

    KAUST Repository

    Mena, B.


    Reliable ground‐motion prediction for future earthquakes depends on the ability to simulate realistic earthquake source models. Though dynamic rupture calculations have recently become more popular, they are still computationally demanding. An alternative is to invoke the framework of pseudodynamic (PD) source characterizations that use simple relationships between kinematic and dynamic source parameters to build physically self‐consistent kinematic models. Based on the PD approach of Guatteri et al. (2004), we propose new relationships for PD models for moderate‐to‐large strike‐slip earthquakes that include local supershear rupture speed due to stress heterogeneities. We conduct dynamic rupture simulations using stochastic initial stress distributions to generate a suite of source models in the magnitude Mw 6–8. This set of models shows that local supershear rupture speed prevails for all earthquake sizes, and that the local rise‐time distribution is not controlled by the overall fault geometry, but rather by local stress changes on the faults. Based on these findings, we derive a new set of relations for the proposed PD source characterization that accounts for earthquake size, buried and surface ruptures, and includes local rise‐time variations and supershear rupture speed. By applying the proposed PD source characterization to several well‐recorded past earthquakes, we verify that significant improvements in fitting synthetic ground motion to observed ones is achieved when comparing our new approach with the model of Guatteri et al. (2004). The proposed PD methodology can be implemented into ground‐motion simulation tools for more physically reliable prediction of shaking in future earthquakes.

  3. Fatigue crack propagation analysis of plaque rupture. (United States)

    Pei, Xuan; Wu, Baijian; Li, Zhi-Yong


    Rupture of atheromatous plaque is the major cause of stroke or heart attack. Considering that the cardiovascular system is a classic fatigue environment, plaque rupture was treated as a chronic fatigue crack growth process in this study. Fracture mechanics theory was introduced to describe the stress status at the crack tip and Paris' law was used to calculate the crack growth rate. The effect of anatomical variation of an idealized plaque cross-section model was investigated. The crack initiation was considered to be either at the maximum circumferential stress location or at any other possible locations around the lumen. Although the crack automatically initialized at the maximum circumferential stress location usually propagated faster than others, it was not necessarily the most critical location where the fatigue life reached its minimum. We found that the fatigue life was minimum for cracks initialized in the following three regions: the midcap zone, the shoulder zone, and the backside zone. The anatomical variation has a significant influence on the fatigue life. Either a decrease in cap thickness or an increase in lipid pool size resulted in a significant decrease in fatigue life. Comparing to the previously used stress analysis, this fatigue model provides some possible explanations of plaque rupture at a low stress level in a pulsatile cardiovascular environment, and the method proposed here may be useful for further investigation of the mechanism of plaque rupture based on in vivo patient data.

  4. Fault geometry of 2015, Mw7.2 Murghab, Tajikistan earthquake controls rupture propagation: Insights from InSAR and seismological data (United States)

    Sangha, Simran; Peltzer, Gilles; Zhang, Ailin; Meng, Lingsen; Liang, Cunren; Lundgren, Paul; Fielding, Eric


    Combining space-based geodetic and array seismology observations can provide detailed information about earthquake ruptures in remote regions. Here we use Landsat-8 imagery and ALOS-2 and Sentinel-1 radar interferometry data combined with data from the European seismology network to describe the source of the December 7, 2015, Mw7.2 Murghab (Tajikistan) earthquake. The earthquake reactivated a ∼79 km-long section of the Sarez-Karakul Fault, a NE oriented sinistral, trans-tensional fault in northern Pamir. Pixel offset data delineate the geometry of the surface break and line of sight ground shifts from two descending and three ascending interferograms constrain the fault dip and slip solution. Two right-stepping, NE-striking segments connected by a more easterly oriented segment, sub-vertical or steeply dipping to the west were involved. The solution shows two main patches of slip with up to 3.5 m of left lateral slip on the southern and central fault segments. The northern segment has a left-lateral and normal oblique slip of up to a meter. Back-projection of high-frequency seismic waves recorded by the European network, processed using the Multitaper-MUSIC approach, focuses sharply along the surface break. The time progression of the high-frequency radiators shows that, after a 10 second initiation phase at slow speed, the rupture progresses in 2 phases at super-shear velocity (∼4.3-5 km/s) separated by a 3 second interval of slower propagation corresponding to the passage through the restraining bend. The intensity of the high-frequency radiation reaches maxima during the initial and middle phases of slow propagation and is reduced by ∼50% during the super-shear phases of the propagation. These findings are consistent with studies of other strike-slip earthquakes in continental domain, showing the importance of fault geometric complexities in controlling the speed of fault propagation and related spatiotemporal pattern of the high-frequency radiation.

  5. Calculation of the local rupture speed of dynamically propagating earthquakes

    Directory of Open Access Journals (Sweden)

    Andrea Bizzarri


    Full Text Available The velocity at which a propagating earthquake advances on the fault surface is of pivotal importance in the contest of the source dynamics and in the modeling of the ground motions generation. In this paper the problem of the determination of the rupture speed (v_r is considered. The comparison of different numerical schemes to compute vr from the rupture time (t_r shows that, in general, central finite differences schemes are more accurate than forward or backward schemes, regardless the order of accuracy. Overall, the most efficient and accurate algorithm is the five–points stencil method at the second–order of accuracy. It is also shown how the determination of t_r can affect v_r ; numerical results indicate that if the fault slip velocity threshold (v_l used to define t_r is too high (v_l ≥ 0.1 m/s the details of the rupture are missed, for instance the rupture tip bifurcation occurring for 2–D supershear rupture. On the other hand, for v_l ≤ 0.01 m/s the results appear to be stable and independent on the choice of v_l . Finally, it is demonstrated that in the special case of the linear slip–weakening friction law the definitions of t_r from the threshold criterion on the fault slip velocity and from the achievement of the maximum yield stress are practically equivalent.

  6. Galerkin boundary integral equation method for spontaneous rupture propagation problems (United States)

    Goto, H.; Bielak, J.


    We develop a Galerkin finite element boundary integral equation method (GaBIEM) for spontaneous rupture propagation problems for a planar fault embedded in a homogeneous full 2D space. A simple 2D anti plane rupture propagation problem, with a slip-weakening friction law, is simulated by the GaBIEM. This method allows one to separate explicitly the kernel into singular static and time-dependent parts, and a nonsingular dynamic component. The simulated results throw light into the performance of the GaBIEM and highlight differences with respect to that of the traditional, collocation, boundary integral equation method (BIEM). The rate of convergence of the GaBIEM, as measured from a root mean square (RMS) analysis of the difference of approximate solutions corresponding to increasingly finer element sizes is of a higher order than that of the BIEM. There is no restriction on the CFL stability number since an implicit, unconditionally stable method is used for the time integration. The error of the approximation increases with the time step, as expected, and it can remain below that of the BIEM.

  7. The transition of dynamic rupture styles in elastic media under velocity-weakening friction

    KAUST Repository

    Gabriel, A.-A.


    Although kinematic earthquake source inversions show dominantly pulse-like subshear rupture behavior, seismological observations, laboratory experiments and theoretical models indicate that earthquakes can operate with different rupture styles: either as pulses or cracks, that propagate at subshear or supershear speeds. The determination of rupture style and speed has important implications for ground motions and may inform about the state of stress and strength of active fault zones. We conduct 2D in-plane dynamic rupture simulations with a spectral element method to investigate the diversity of rupture styles on faults governed by velocity-and-state-dependent friction with dramatic velocity-weakening at high slip rate. Our rupture models are governed by uniform initial stresses, and are artificially initiated. We identify the conditions that lead to different rupture styles by investigating the transitions between decaying, steady state and growing pulses, cracks, sub-shear and super-shear ruptures as a function of background stress, nucleation size and characteristic velocity at the onset of severe weakening. Our models show that small changes of background stress or nucleation size may lead to dramatic changes of rupture style. We characterize the asymptotic properties of steady state and self-similar pulses as a function of background stress. We show that an earthquake may not be restricted to a single rupture style, but that complex rupture patterns may emerge that consist of multiple rupture fronts, possibly involving different styles and back-propagating fronts. We also demonstrate the possibility of a super-shear transition for pulse-like ruptures. Finally, we draw connections between our findings and recent seismological observations.

  8. One- / Two-Dimensional versus Three-Dimensional Rupture Propagation in Brittle Solids (United States)

    Uenishi, K.


    Source dynamics of normal earthquakes is usually considered in the framework of 3D rupture in brittle solids. However, our understanding of mechanical details of actual 3D rupture is limited and most of the frequently utilized rupture criteria in earthquake science have been derived from 1D (or at most 2D) experiments. Typically, criteria based on 1D frictional observations of sliding materials are quite often employed in seismological simulations, but we are not sure whether these rupture criteria are really valid for the generation and complex propagation process of 3D rupture. Indeed, our recent experimental observations on dynamic rupture of monolithic brittle solids using a high-speed digital video camera system indicate rather complicated histories of rupture development in 3D solid materials but at the same time they show simple final rupture patterns (rupture networks). For example, by concurrently applying high-voltage electric discharge impulses, a controlled and geometrically plain dynamic rupture pattern can be really obtained in cylindrical concrete specimens, but the simple final rupture pattern is formed not by unidirectional rupture propagation but by multi-directional one. Another example of plain final rupture patterns can be found by dynamic experiments of ice spheres that impinge upon a flat polycarbonate or ice plate. Rupture of the ice spheres induced by the mechanical impact (free fall) shows two representative rupture patterns: (i) The ice sphere is mainly divided into three or four large segments of comparable size (similar to orange segments); and (ii) Only some portions near the bottom of the ice sphere are ruptured into pieces upon collision and a relatively large "top"-shaped part remains unbroken. Both experimental observations indicate generation of remarkably simple and frequently flat rupture surfaces in 3D specimens even without the clear existence of planes of weakness, but it seems difficult to explain the dynamic rupture

  9. Steady-state propagation speed of rupture fronts along 1D frictional interfaces

    CERN Document Server

    Amundsen, David Skålid; Thøgersen, Kjetil; Katzav, Eytan; Malthe-Sørenssen, Anders; Scheibert, Julien


    The rupture of dry frictional interfaces occurs through the propagation of fronts breaking the contacts at the interface. Recent experiments have shown that the velocities of these rupture fronts range from quasi-static velocities proportional to the external loading rate to velocities larger than the shear wave speed. The way system parameters influence front speed is still poorly understood. Here we study steady-state rupture propagation in a 1D spring-block model of an extended frictional interface, for various friction laws. With the classical Amontons--Coulomb friction law, we derive a closed-form expression for the steady-state rupture velocity as a function of the interfacial shear stress just prior to rupture. We then consider an additional shear stiffness of the interface and show that the softer the interface, the slower the rupture fronts. We provide an approximate closed form expression for this effect. We finally show that adding a bulk viscosity on the relative motion of blocks accelerates stead...

  10. Segmentation Along the Newport-Inglewood Rose Canyon Fault Zone: Implications for Rupture Propagation (United States)

    Sahakian, V. J.; Bormann, J. M.; Driscoll, N. W.; Harding, A. J.; Kent, G. M.; Wesnousky, S. G.


    The Newport-Inglewood/Rose Canyon fault zone (NIRC) is an active component of the southern California strike-slip fault system in the Pacific-North American plate boundary. Despite its close proximity to densely populated coastal regions of Southern California, the NIRC fault geometry and expected earthquake behavior are poorly constrained. As a result of these uncertainties, current hazard models lack critical information regarding potential earthquake magnitudes and ground shaking caused by rupture on the offshore portion of the fault. Here, we present an improved characterization of the NIRC fault zone's architecture and segmentation. We employ nested marine seismic reflection data of varying vertical resolutions to map the NIRC location, strike, dip, and stepovers based on subsurface observations. These reflection data were collected in 1979, 2006, 2008, 2009 and 2013. We identify four main geometrical fault segments separated along strike by three stepovers between 0.5 and 3 km in width, whereby width is measured as the horizontal distance between fault strands or termini. Empirical studies of rupture propagation show that past earthquake ruptures in other regions have propagated across discontinuities of this width. We additionally employ a quantitative approach to constrain the potential earthquake magnitude for the NIRC fault zone by modeling the coulomb stress changes that result from possible rupture initiation scenarios. Earthquakes initiated on the central fault strand by Carlsbad Canyon favor through-going rupture across the entire length of the NIRC fault zone. Additionally, the modeling results suggest that the southernmost stepover by La Jolla may act as an inhibitor to through-going rupture due to the strike and dip of the adjacent fault despite the stepover's short width. Finally, our stress modeling results suggest that the maximum potential magnitude of an earthquake rupturing all of the mapped offshore segments of the NIRC fault zone is Mw 7.5.

  11. Dynamic rupture simulation with an experimentally-determined friction law leads to slip-pulse propagation (United States)

    Liao, Z.; Chang, J. C.; Reches, Z.


    We simulate the dynamic rupture along a vertical, strike-slip fault in an elastic half-space. The fault has frictional properties that were determined in high-velocity, rotary shear apparatus Sierra-White granite. The experimental fault was abruptly loaded by a massive flywheel, which is assumed to simulate the loading of a fault patch during an earthquake, and termed Earthquake-Like-Slip Event (ELSE) (Chang et al., 2012). The experiments revealed systematic alteration between slip-weakening and slip-strengthening (Fig. 1A), and were considered as proxies of fault-patch behavior during earthquakes of M = 4-8. We used the friction-distance relations of these experiments to form an empirical slip-dependent friction model, ELSE-model (Fig. 1B). For the dynamic rupture simulation, we used the program of Ampuero (2002) (2D spectral boundary integral elements) designed for anti-plane (mode III) shear fracturing. To compare with published works, the calculations used a crust with mechanical properties and stress state of Version 3 benchmark of SCEC (Harris et al., 2004). The calculations with a fault of ELSE-model friction revealed: (1) Rupture propagation in a slip-pulse style with slip cessation behind the pulse; (2) Systematic decrease of slip distance away from the nucleation zone; and (3) Spontaneous arrest of the dynamic rupture without a barrier. These features suggest a rupture of a self-healing slip-pulse mode (Fig. 1C), in contrast to rupturing of a fault with linear slip-weakening friction (Fig. 1B) (Rojas et al., 2008) in crack-like mode and no spontaneous arrest. We deduce that the slip-pulse in our simulation results from the fast recovery of shear strength as observed in ELSE experiments, and argue that incorporating this experimentally-based friction model to rupture modeling produces realistic propagation style of earthquake rupture. Figure 1 Fault patch behavior during an earthquake. (A) Experimental evolution of frictional stress, slip velocity, and

  12. Conditions Under Which Megathrust Ruptures Propagate Through Shallow Velocity-Weakening Regions to the Trench (United States)

    Dunham, E. M.; Kozdon, J. E.; Lotto, G. C.


    We have conducted dynamic rupture simulations of the 11 March 2011 Tohoku earthquake to identify conditions that permit megathrust ruptures to reach the trench, even when the uppermost portion of the plate interface is frictionally stable. Our models incorporate rate-and-state friction featuring depth-dependent properties that transition from velocity-weakening at depth to velocity-strengthening beneath the accretionary prism. Earthquake nucleation is thus restricted to greater depths, consistent with the lack of shallow seismicity near the trench. Despite this, we find that unless the uppermost velocity-strengthening section of the fault extends beyond about 50 km along dip, ruptures propagating upward from depth break through to the trench. Stress changes, carried by seismic waves released by deep slip, provide the necessary driving force that maintains propagation even in the absence of frictional weakening and stress drop. In our present set of simulations, we assume ideally elastic response of the off-fault material. We therefore caution that our conclusions will likely be modified by the occurrence of plastic deformation within the accretionary prism, which we are planning to explore in the near future. Our models are calibrated through comparison with seafloor deformation measurements and onshore 1-Hz GPS data. We explore the ability of these data sets to constrain frictional properties along the plate interface, particularly in the near-trench region. Our modeling efforts thus far suggest strong trade-offs between stress drop along the deeper part of the fault and the shallow frictional properties. In addition to our preferred model featuring a shallow velocity-strengthening section, we can equally well fit the data with velocity-weakening properties extending all the way to the trench, provided we decrease the average stress drop by reducing the initial effective normal stress. We are also examining the signature of extreme shallow slip in hydroacoustic

  13. Coherence of Mach fronts during heterogeneous supershear earthquake rupture propagation: Simulations and comparison with observations (United States)

    Bizzarri, A.; Dunham, Eric M.; Spudich, P.


    We study how heterogeneous rupture propagation affects the coherence of shear and Rayleigh Mach wavefronts radiated by supershear earthquakes. We address this question using numerical simulations of ruptures on a planar, vertical strike-slip fault embedded in a three-dimensional, homogeneous, linear elastic half-space. Ruptures propagate spontaneously in accordance with a linear slip-weakening friction law through both homogeneous and heterogeneous initial shear stress fields. In the 3-D homogeneous case, rupture fronts are curved owing to interactions with the free surface and the finite fault width; however, this curvature does not greatly diminish the coherence of Mach fronts relative to cases in which the rupture front is constrained to be straight, as studied by Dunham and Bhat (2008a). Introducing heterogeneity in the initial shear stress distribution causes ruptures to propagate at speeds that locally fluctuate above and below the shear wave speed. Calculations of the Fourier amplitude spectra (FAS) of ground velocity time histories corroborate the kinematic results of Bizzarri and Spudich (2008a): (1) The ground motion of a supershear rupture is richer in high frequency with respect to a subshear one. (2) When a Mach pulse is present, its high frequency content overwhelms that arising from stress heterogeneity. Present numerical experiments indicate that a Mach pulse causes approximately an ω−1.7 high frequency falloff in the FAS of ground displacement. Moreover, within the context of the employed representation of heterogeneities and over the range of parameter space that is accessible with current computational resources, our simulations suggest that while heterogeneities reduce peak ground velocity and diminish the coherence of the Mach fronts, ground motion at stations experiencing Mach pulses should be richer in high frequencies compared to stations without Mach pulses. In contrast to the foregoing theoretical results, we find no average elevation

  14. Galerkin boundary integral equation method for spontaneous rupture propagation problems: SH-case (United States)

    Goto, Hiroyuki; Bielak, Jacobo


    We develop a Galerkin finite element boundary integral equation method (GaBIEM) for spontaneous rupture propagation problems for a planar fault embedded in a homogeneous full 2-D space. A 2-D antiplane rupture propagation problem, with a slip-weakening friction law, is simulated by the GaBIEM. This method allows one to eliminate the strong singularities from the integral representation of the traction, and to separate explicitly the expression for the traction into an instantaneous component; static and time-dependent components with weakly (logarithmic) singular kernels; and a dynamic component and a quasi-static component, with continuous, bounded, kernels. Simulated results throw light into the performance of the GaBIEM and highlight differences with respect to that of the traditional, collocation, boundary integral equation method (BIEM). Both methods converge with a power law with respect to grid size, with different exponents. There is no restriction on the CFL stability number for the GaBIEM since an implicit, unconditionally stable method is used for the time integration. The error of the approximation increases with the time step, as expected, and it can remain below that of the BIEM.

  15. The ADER-DG method for seismic wave propagation and earthquake rupture dynamics (United States)

    Pelties, Christian; Gabriel, Alice; Ampuero, Jean-Paul; de la Puente, Josep; Käser, Martin


    We will present the Arbitrary high-order DERivatives Discontinuous Galerkin (ADER-DG) method for solving the combined elastodynamic wave propagation and dynamic rupture problem. The ADER-DG method enables high-order accuracy in space and time while being implemented on unstructured tetrahedral meshes. A tetrahedral element discretization provides rapid and automatized mesh generation as well as geometrical flexibility. Features as mesh coarsening and local time stepping schemes can be applied to reduce computational efforts without introducing numerical artifacts. The method is well suited for parallelization and large scale high-performance computing since only directly neighboring elements exchange information via numerical fluxes. The concept of fluxes is a key ingredient of the numerical scheme as it governs the numerical dispersion and diffusion properties and allows to accommodate for boundary conditions, empirical friction laws of dynamic rupture processes, or the combination of different element types and non-conforming mesh transitions. After introducing fault dynamics into the ADER-DG framework, we will demonstrate its specific advantages in benchmarking test scenarios provided by the SCEC/USGS Spontaneous Rupture Code Verification Exercise. An important result of the benchmark is that the ADER-DG method avoids spurious high-frequency contributions in the slip rate spectra and therefore does not require artificial Kelvin-Voigt damping, filtering or other modifications of the produced synthetic seismograms. To demonstrate the capabilities of the proposed scheme we simulate an earthquake scenario, inspired by the 1992 Landers earthquake, that includes branching and curved fault segments. Furthermore, topography is respected in the discretized model to capture the surface waves correctly. The advanced geometrical flexibility combined with an enhanced accuracy will make the ADER-DG method a useful tool to study earthquake dynamics on complex fault systems in

  16. Towards continuum models of lateral rupture propagation in a segmented megathrust (United States)

    Pranger, C. C.; van Dinther, Y.; Le Pourhiet, L.; May, D.; Gerya, T.


    At subduction megathrusts, propagation of large ruptures may be confined between the up-dip and down-dip limits of the seismogenic zone. This opens a primary role for lateral rupture dimensions to control the magnitude and severity of megathrust earthquakes. The goal of this study is to improve our understanding of the ways in which the inherent variability of the subduction interface may influence the degree of interseismic locking, and the propensity of a rupture to propagate over regions of variable slip potential. We focus in particular on the roughness of the incoming seafloor, which we expect to be of primary importance. The global absence of a historic record sufficiently long to base risk assessment on, makes us rely on numerical modelling as a way to extend our understanding of the spatio-temporal occurrence of earthquakes. However, the complex interaction of the subduction stress environment, the variability of the subduction interface, and the structure and deformation of the crustal wedge has made it very difficult to construct comprehensive numerical models of megathrust segmentation. We intend to develop and exploit the power of a plastic 3D continuum representation of the subduction megathrust, as well as off-megathrust faulting to model the long-term tectonic build-up of stresses, and their sudden seismic release. The sheer size of the 3D problem, and the time scales covering those of tectonics as well as seismology, force us to explore efficient and accurate physical and numerical techniques. So far, we have focused our efforts on developing a staggered grid finite difference code that makes use of the PETSc library for massively parallel computing. The code incorporates a newly developed automatic discretization algorithm, which enables it to handle a wide variety of equations with relative ease. What remains now is combining the physics that act on the different spatial and temporal scales. To this end we explore new constitutive models that

  17. Rupture

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    Our Director-General is indifferent to the tradition of concertation foreseen in our statutes and is "culturally" unable to associate the Staff Association with problem-solving in staff matters. He drags his heels as long as possible before entering into negotiations, presents "often misleading" solutions at the last minute which he only accepts to change once a power struggle has been established. Faced with this rupture and despite its commitment to concertation between gentlemen. The results of the poll in which the staff is invited to participate this week. We therefore need your support to state our claims to the Governing Bodies. The Staff Association proposes a new medium of communication and thus hopes to show that it is ready for future negotiations. The pages devoted to the Staff Association are presented in a more informative, reactive and factual manner and in line with the evolution of the social situation at CERN. We want to establish strong and continuous ties between the members of CERN and ou...

  18. Rupture Propagation of the 2013 Mw7.7 Balochistan, Pakistan, Earthquake Affected by Poroelastic Stress Changes (United States)

    He, J.; Wang, W.; Xiao, J.


    The 2013 Mw7.7 Balochistan, Pakistan, earthquake occurred on the curved Hoshab fault. This fault connects with the north-south trending Chaman strike-slip fault to northeast, and with the west-east trending Makran thrust fault system to southwest. Teleseismic waveform inversion, incorporated with coseismic ground surface deformation data, show that the rupture of this earthquake nucleated around northeast segment of the fault, and then propagated southwestward along the northwest dipping Hoshab fault about 200 km, with the maximum coseismic displacement, featured mainly by purely left-lateral strike-slip motion, about 10 meters. In context of the India-Asia collision frame, associating with the fault geometry around this region, the rupture propagation of this earthquake seems to not follow an optimal path along the fault segment, because after nucleation of this event the Hoshab fault on the southwest of hypocenter of this earthquake is clamped by elastic stress change. Here, we build a three-dimensional finite-element model to explore the evolution of both stress and pore-pressure during the rupturing process of this earthquake. In the model, the crustal deformation is treated as undrained poroelastic media as described by Biot's theory, and the instantaneous rupture process is specified with split-node technique. By testing a reasonable range of parameters, including the coefficient of friction, the undrained Poisson's ratio, the permeability of the fault zone and the bulk crust, numerical results have shown that after the nucleation of rupture of this earthquake around the northeast of the Hoshab fault, the positive change of normal stress (clamping the fault) on the fault plane is greatly reduced by the instantaneous increase of pore pressure (unclamping the fault). This process could result in the change of Coulomb failure stress resolved on the Hoshab fault to be hastened, explaining the possible mechanism for southwestward propagation of rupture of the Mw7

  19. The frictional properties of faults at shallow depths: implications for rupture propagation. (United States)

    De Paola, Nicola; Bullock, Rachael; Unwin, Rachel; Murray, Rosanne; Stillings, Mark; Holdsworth, Robert


    Most synoptic models of faults assume the presence of a shallow stable, velocity-strengthening aseismic region due to the presence of incohesive gouges, poorly lithified continental sediments (continental faults) and phyllosilicate-rich rocks (accretionary prisms at subduction zones). The near-surface portions of faults are therefore viewed as effective energy sinks with the potential to arrest/slow down the propagation of earthquakes, preventing them from reaching the surface. However, recent events, such as the 2009 Mw 6.3 L'Aquila and 2011 Mw 9.0 Tohoku-Oki earthquakes, have demonstrated that moderate/large co-seismic ruptures can propagate to the surface causing vast damage and destructive tsunamis. In order to better understand rupture propagation at shallow depths, we investigated the frictional properties of a range of bedrock lithologies, typical of the oceanic (gabbros) and continental crusts (granite, limestone), together with phyllosilicate-bearing lithologies typical of subduction zones and continental sedimentary deposits. Laboratory experiments have been performed in a low to high velocity rotary shear apparatus, on granular materials with grainsize up to 200 μm, under dry, water- and brine-saturated conditions, at slip rates ranging from 10 μm/s up to 1 m/s, with normal loads up to 18 MPa and displacements up to 1 m. Velocity step experiments performed at sub-seismic slip rates (10-100 μm/s) on dry, water- and brine-saturated granite and calcite rocks show that velocity strengthening behaviour evolves to velocity-neutral/-weakening behaviour due to slip localization attained after critical displacements of a few tens to hundreds of mm. The critical displacement value is inversely proportional to the applied normal load. Dry, water- and brine-saturated gabbros show velocity-weakening behaviour and slip localization regardless of the displacement attained and applied normal load. Dry, water- and brine-saturated phyllosilicate-rich gouges show

  20. High-Speed Observations of Dynamic Fracture Propagation in Solids and Their Implications in Earthquake Rupture Dynamics (United States)

    Uenishi, Koji


    This contribution outlines our experimental observations of seismicity-related fast fracture (rupture) propagation in solids utilising high-speed analog and digital photography (maximum frame rate 1,000,000 frames per second) over the last two decades. Dynamic fracture may be triggered or initiated in the monolithic or layered seismic models by detonation of micro explosives, a projectile launched by a gun, laser pulses and electric discharge impulses, etc. First, we have investigated strike-slip rupture along planes of weakness in transparent photoelastic (birefringent) materials at a laboratory scale and shown (at that time) extraordinarily fast rupture propagation in a bi-material system and its possible effect on the generation of large strong motion in the limited narrow areas in the Kobe region on the occasion of the 1995 Hyogo-ken Nanbu, Japan, earthquake (Uenishi Ph.D. thesis 1997, Uenishi et al. BSSA 1999). In this series of experiments, we have also modelled shallow dip-slip earthquakes and indicated a possible origin of the asymmetric ground motion in the hanging and foot-walls. In the photoelastic photographs, we have found the unique dynamic wave interaction and generation of specific shear and interface waves numerically predicted by Uenishi and Madariaga (Eos 2005), and considered as a case study the seismic motion associated with the 2014 Nagano-ken Hokubu (Kamishiro Fault), Japan, dip-slip earthquake (Uenishi EFA 2015). Second, we have experimentally shown that even in a monolithic material, rupture speed may exceed the local shear wave speed if we employ hyperelasically behaving materials like natural rubber (balloons) (Uenishi Eos 2006, Uenishi ICF 2009, Uenishi Trans. JSME A 2012) but fracture in typical monolithic thin fluid films (e.g. soap bubbles, which may be treated as a solid material) propagates at an ordinary subsonic (sub-Rayleigh) speed (Uenishi et al. SSJ 2006). More recent investigation handling three-dimensional rupture propagation

  1. 3D dynamic rupture with anelastic wave propagation using an hp-adaptive Discontinuous Galerkin method (United States)

    Tago, J.; Cruz-Atienza, V. M.; Etienne, V.; Virieux, J.; Benjemaa, M.; Sanchez-Sesma, F. J.


    Simulating any realistic seismic scenario requires incorporating physical basis into the model. Considering both the dynamics of the rupture process and the anelastic attenuation of seismic waves is essential to this purpose and, therefore, we choose to extend the hp-adaptive Discontinuous Galerkin finite-element method to integrate these physical aspects. The 3D elastodynamic equations in an unstructured tetrahedral mesh are solved with a second-order time marching approach in a high-performance computing environment. The first extension incorporates the viscoelastic rheology so that the intrinsic attenuation of the medium is considered in terms of frequency dependent quality factors (Q). On the other hand, the extension related to dynamic rupture is integrated through explicit boundary conditions over the crack surface. For this visco-elastodynamic formulation, we introduce an original discrete scheme that preserves the optimal code performance of the elastodynamic equations. A set of relaxation mechanisms describes the behavior of a generalized Maxwell body. We approximate almost constant Q in a wide frequency range by selecting both suitable relaxation frequencies and anelastic coefficients characterizing these mechanisms. In order to do so, we solve an optimization problem which is critical to minimize the amount of relaxation mechanisms. Two strategies are explored: 1) a least squares method and 2) a genetic algorithm (GA). We found that the improvement provided by the heuristic GA method is negligible. Both optimization strategies yield Q values within the 5% of the target constant Q mechanism. Anelastic functions (i.e. memory variables) are introduced to efficiently evaluate the time convolution terms involved in the constitutive equations and thus to minimize the computational cost. The incorporation of anelastic functions implies new terms with ordinary differential equations in the mathematical formulation. We solve these equations using the same order

  2. Effects of Apparent Supersonic Ruptures for Strike-slip Rupture: Should We Consider it in the Seismic Hazard Analysis? (United States)

    Barrows, M. B.; Shao, G.; Ji, C.


    Recent numerical studies indicated that the supersonic rupture could produce larger off-fault damage at distant sites than the sub-shear rupture, due to the famous "mach cone" effect (Dunham and Archuleta, 2005; Bhat et al, 2007). These results were obtained using the steady-state rupture simulations in a half-space earth. For more realistic layered or 3D earth models, we should also consider the effects of apparent supersonic rupture, i.e., the deep rupture is still in a speed slower than the local shear velocity, but faster than the near surface S or even the P wave velocity. The apparent super-shear rupture could excite the mach effect, but how large it is has not yet been quantitatively addressed. In this study, we explore this possibility by performing numerical simulations for pure strike-slip ruptures on a vertical fault inside various layered earth models.

  3. Laboratory Earthquake Measurements with the High-speed Digital Image Correlation Method and Applications to Super-shear Transition (United States)

    Rubino, V.; Lapusta, N.; Rosakis, A.


    Mapping full-field displacements and strains on the Earth's surface during an earthquake is of paramount importance to enhance our understanding of earthquake mechanics. In this study, the feasibility of such measurements using image correlation methods is investigated in a laboratory earthquake setup. Earthquakes are mimicked in the laboratory by dynamic rupture propagating along an inclined frictional interface formed by two Homalite plates under compression, using the configuration developed by Rosakis and coworkers (e.g., Rosakis et al., 2007). In our study, the interface is partially glued, in order to confine the rupture before it reaches the ends of the specimen. The specimens are painted with a speckle pattern to provide the surface with characteristic features for image matching. Images of the specimens are taken before and after dynamic rupture with a 4 Megapixels resolution CCD camera. The digital images are analyzed with two software packages: VIC-2D (Correlated Solutions Inc.) and COSI-Corr (Leprince et. al, 2007). Both VIC-2D and COSI-Corr are able to characterize the full-field static displacement of a dynamic crack. For example, in a case with secondary mode I cracks, the correlation analysis performed with either software clearly shows (i) the relative displacement (slip) along the frictional interface, (ii) the rupture arrest on the glued boundaries, and (iii) the presence of two wing cracks. The obtained displacement measurements are converted to strains, using de-noising techniques. The digital image correlation method is then used in combination with high-speed photography. We will report our progress on the study of a spontaneously expanding sub-Rayleigh shear crack advancing along an interface containing a patch of favorable heterogeneity, such as a preexisting subcritical crack or a patch with higher prestress. According to the predictions of Liu and Lapusta (2008), intersonic transition and propagation can be achieved in the presence of a

  4. Origin of Columbia River flood basalt controlled by propagating rupture of the Farallon slab. (United States)

    Liu, Lijun; Stegman, Dave R


    The origin of the Steens-Columbia River (SCR) flood basalts, which is presumed to be the onset of Yellowstone volcanism, has remained controversial, with the proposed conceptual models involving either a mantle plume or back-arc processes. Recent tomographic inversions based on the USArray data reveal unprecedented detail of upper-mantle structures of the western USA and tightly constrain geodynamic models simulating Farallon subduction, which has been proposed to influence the Yellowstone volcanism. Here we show that the best-fitting geodynamic model depicts an episode of slab tearing about 17 million years ago under eastern Oregon, where an associated sub-slab asthenospheric upwelling thermally erodes the Farallon slab, leading to formation of a slab gap at shallow depth. Driven by a gradient of dynamic pressure, the tear ruptured quickly north and south and within about two million years covering a distance of around 900 kilometres along all of eastern Oregon and northern Nevada. This tear would be consistent with the occurrence of major volcanic dikes during the SCR-Northern Nevada Rift flood basalt event both in space and time. The model predicts a petrogenetic sequence for the flood basalt with sources of melt starting from the base of the slab, at first remelting oceanic lithosphere and then evolving upwards, ending with remelting of oceanic crust. Such a progression helps to reconcile the existing controversies on the interpretation of SCR geochemistry and the involvement of the putative Yellowstone plume. Our study suggests a new mechanism for the formation of large igneous provinces.

  5. Self-healing vs. Crack-like Rupture Propagation in Presence of Thermal Weakening Processes Based on Realistic Physical Properties (United States)

    Noda, H.; Dunham, E. M.; Rice, J. R.


    We have conducted rupture propagation simulations allowing for the combined effects of thermal pressurization of pore fluid and flash heating of microscopic contact asperities. Rapid, large slip as in earthquakes produces a large amount of frictional heat, and probably activates such thermal weakening mechanisms. They act until macroscopic fault temperature T nears the melting point, and are coupled through T and macroscopic fault surface pore pressure p. Because we consider two mechanisms, the characteristic slip for each of them is physically important; a compromise on one of them can eventually nullify its effect compared to the other. We use a range of realistic hydraulic properties for thermal pressurization (hydro-thermal diffusivity factor 20-450 mm2/s; factor corresponds to f2VL_*/4=(ρ c/Λ)2(√{αth}+√{αhy})2 [Rice, JGR, 2006] where f is the friction coefficient, V is slip rate, L_* is a characteristic slip defined in the thermal pressurization analysis, ρ c is specific heat, Λ is pore pressure rise per unit temperature rise in undrained conditions, and αth and αhy are thermal and hydraulic diffusivities), and microns of contact evolution distance L for flash heating with a slip law formulation and the direct effect. We use the spectral implementation of the BIE method for elastodynamic calculations, and set a 1d FD grid normal to the fault plane at each node to calculate local heat and fluid transport assuming an infinitesimally thin slipping plane. We also use a multi-step time increment procedure by setting longer steps for slip history storage and shorter steps for integration of state variable, T, and p. Elasticity and the constitutive relation are solved simultaneously at every shorter time step with linearly interpolated stress transfer. This method reduces the amount of memory but produces numerical stability. We nucleated rupture by adding a sudden perturbation to the shear stress, which is initially uniform and much lower than the static

  6. Achilles Tendon Rupture (United States)

    Achilles tendon rupture Overview By Mayo Clinic Staff Achilles (uh-KILL-eez) tendon rupture is an injury that affects the back ... but it can happen to anyone. The Achilles tendon is a strong fibrous cord that connects the ...

  7. Ruptured abdominal aortic aneurysm. (United States)

    Sachs, T; Schermerhorn, M


    Ruptured abdominal aortic aneurysm (AAA) continues to be one of the most lethal vascular pathologies we encounter. Its management demands prompt and efficient evaluation and repair. Open repair has traditionally been the mainstay of treatment. However, the introduction of endovascular techniques has altered the treatment algorithm for ruptured AAA in most major medical centers. We present recent literature and techniques for ruptured AAA and its surgical management.

  8. Fan-structure waves in shear ruptures (United States)

    Tarasov, Boris


    This presentation introduces a recently identified shear rupture mechanism providing a paradoxical feature of hard rocks - the possibility of shear rupture propagation through the highly confined intact rock mass at shear stress levels significantly less than frictional strength. According to the fan-mechanism the shear rupture propagation is associated with consecutive creation of small slabs in the fracture tip which, due to rotation caused by shear displacement of the fracture interfaces, form a fan-structure representing the fracture head. The fan-head combines such unique features as: extremely low shear resistance (below the frictional strength), self-sustaining stress intensification in the rupture tip (providing easy formation of new slabs), and self-unbalancing conditions in the fan-head (making the failure process inevitably spontaneous and violent). An important feature of the fan-mechanism is the fact that for the initial formation of the fan-structure an enhanced local shear stress is required, however, after completion of the fan-structure it can propagate as a dynamic wave through intact rock mass at shear stresses below the frictional strength. Paradoxically low shear strength of pristine rocks provided by the fan-mechanism determines the correspondingly low transient strength of the lithosphere, which favours generation of new earthquake faults in the intact rock mass adjoining pre-existing faults in preference to frictional stick-slip instability along these faults. The new approach reveals an alternative role of pre-existing faults in earthquake activity: they represent local stress concentrates in pristine rock adjoining the fault where special conditions for the fan-mechanism nucleation are created, while further dynamic propagation of the new fault (earthquake) occurs at low field stresses even below the frictional strength.

  9. [Exceptional iatrogenic ureteral rupture]. (United States)

    Martínez-Vieira, Almudena; Valera-Sánchez, Zoraida; Sousa-Vaquero, José María; Palacios-González, Carmen; García-Poley, Antonio; Bernal-Bellido, Carmen; Alamo-Martínez, José María; Millán-López, Ana; Blanco-Domínguez, Manuel; Galindo-Galindo, Antonio


    Rupture of the ureter is an infrequent event that can have serious consequences. The most frequent cause is surgical iatrogenic ureter disease. Other possible causes are urological procedures and urographic studies. In our patient, which, to our knowledge, is the first to be reported in the literature, the ureteral rupture was produced by a traumatic urinary catheterism, because the balloon was filled inside the ureter. The normal presentation is nephritic colic, although acute abdomen is also a possibility. The possibility of ureteral rupture in abdominopelvic surgery or in urological techniques should be evaluated when patients present these clinical symptoms. Treatment is surgical, although in some cases conservative measures can be used.

  10. Ruptured episiotomia resutured primarily. (United States)

    Monberg, J; Hammen, S


    In a randomized study, 35 patients with ruptured episiotomy were treated in two ways. One group, treated with Clindamycin and primary resuture, did better than the other group, not resutured but spontaneously healed.

  11. Achilles tendon rupture - aftercare (United States)

    Heel cord tear; Calcaneal tendon rupture ... MRI scan to see what type of Achilles tendon tear you have. An MRI is a type ... partial tear means at least some of the tendon is still OK. A full tear means your ...

  12. Spontaneous uterine rupture

    African Journals Online (AJOL)

    After ultrasound scan, uterine rupture was diagnosed and an ... delivery. The birth weights ranged between 2900 and 3200g. The last 2 .... abdominal pains and signs of shock, at which made up of altered blood and we think that the.

  13. Distal Biceps Tendon Rupture (United States)


    distal tendon . Although these findings overlap with those seen in tendinopathy , the presence of bone marrow edema at the radial tuberosity and fluid in...the bicipitoradial bursa suggests a partial tear rather than tendinopathy .3 When the distal biceps tendon tear is complete, MR imaging shows...Distal Biceps Tendon Rupture Military Medicine Radiology Corner, 2006 Radiology Corner Distal Biceps Tendon Rupture Contributors: CPT Michael

  14. Rupture of the Pitáycachi Fault in the 1887 Mw 7.5 Sonora, Mexico earthquake (southern Basin-and-Range Province): Rupture kinematics and epicenter inferred from rupture branching patterns (United States)

    Suter, Max


    During the 3 May 1887 Mw 7.5 Sonora earthquake (surface rupture end-to-end length: 101.8 km), an array of three north-south striking Basin-and-Range Province faults (from north to south Pitáycachi, Teras, and Otates) slipped sequentially along the western margin of the Sierra Madre Occidental Plateau. This detailed field survey of the 1887 earthquake rupture zone along the Pitáycachi fault includes mapping the rupture scarp and measurements of surface deformation. The surface rupture has an endpoint-to-endpoint length of ≥41.0 km, dips ~70°W, and is characterized by normal left-lateral extension. The maximum surface offset is 487 cm and the mean offset 260 cm. The rupture trace shows a complex pattern of second-order segmentation. However, this segmentation is not expressed in the 1887 along-rupture surface offset profile, which indicates that the secondary segments are linked at depth into a single coherent fault surface. The Pitáycachi surface rupture shows a well-developed bipolar branching pattern suggesting that the rupture originated in its central part, where the polarity of the rupture bifurcations changes. Most likely the rupture first propagated bilaterally along the Pitáycachi fault. The southern rupture front likely jumped across a step over to the Teras fault and from there across a major relay zone to the Otates fault. Branching probably resulted from the lateral propagation of the rupture after breaching the seismogenic part of the crust, given that the much shorter ruptures of the Otates and Teras segments did not develop branches.

  15. Brittle dynamic damage due to earthquake rupture (United States)

    Bhat, Harsha; Thomas, Marion


    The micromechanical damage mechanics formulated by Ashby and Sammis, 1990, and generalized by Deshpande and Evans 2008 has been extended to allow for a more generalized stress state and to incorporate an experimentally motivated new crack growth (damage evolution) law that is valid over a wide range of loading rates. This law is sensitive to both the crack tip stress field and its time derivative. Incorporating this feature produces additional strain-rate sensitivity in the constitutive response. The model is also experimentally verified by predicting the failure strength of Dionysus-Pentelicon marble over wide range of strain rates. We then implement this constitutive response to understand the role of dynamic brittle off-fault damage on earthquake ruptures. We show that off-fault damage plays an important role in asymmetry of rupture propagation and is a source of high-frequency ground motion in the near source region.

  16. Anomalous statistics of aftershock sequences generated by supershear ruptures

    Directory of Open Access Journals (Sweden)

    Pathikrit Bhattacharya


    Full Text Available Most earthquake ruptures propagate with speeds smaller than the Rayleigh wave velocity of the medium. These are called sub- Rayleigh ruptures. However, under suitable conditions, segments of otherwise sub- Rayleigh seismogenic ruptures can occasionally accelerate to speeds higher than the local shear wave velocity, giving rise to so-called supershear ruptures. The occurrence of supershear ruptures is usually associated with a locally higher value of pre-stress on the fault segment compared to the sub-Rayleigh segments of the same fault. Additionally, shear stress changes generated by the supershear rupture are radiated out unattenuated to distances comparable to the depth of rupture instead of rapidly decaying at much smaller distances from the rupture. This leads to aftershocks being distributed away from the fault on the supershear segment. This study attempts to verify whether these pre- and postseismic stress conditions and the resultant spatial aftershock distributions lead to discernible features in the statistical properties of the aftershock sequences of the earthquakes known to be associated with supershear ruptures. We analyze the Gutenberg-Richter scaling, the modified Omori law and Båth’s law for the aftershock sequences of two supershear mainshocks: the 1979 MW 6.5 Imperial Valley (California and 2002 MW 7.9 Denali (Alaska earthquakes. We observe that the b-value is always higher in the supershear zone than the rest of the sequence. We also observe that there is no systematic trend in the exponent of the modified Omori law when comparing the aftershocks in the supershear zone with the rest of the aftershocks. We argue that the b-value anomaly can be explained in terms of the off-fault distribution of aftershocks around the supershear segment of the rupture.

  17. Mitigation measures for soil embankments against fault rupture using geosynthetics

    DEFF Research Database (Denmark)

    Zania, Varvara; Tsompanakis, Yiannis; Psarropoulos, Prodromos


    In the current study the ability of geosynthetics to reduce the permanent deformations developed due to a fault rupture propagation in a soil embankment is investigated. For this purpose parametric numerical analyses were performed and the effect of the material properties of the geosynthetics...

  18. Dynamic rupture of megathrust earthquakes with branching on splay faults (United States)

    Somala, S.; Ampuero, J. P.; Lapusta, N.


    The accretionary prism of subduction margins generally contains splay faults that approach the surface at steeper angles than the megathrust interface. Rupture propagating onto splay faults during megathrust earthquakes can increase seafloor uplift significantly and contribute to the potential of tsunami. Another key aspect of tsunamigenic earthquakes is their relatively low radiation efficiency, which could be related to slow rupture at shallow depth due to frictionally stable fault properties. We present here results of numerical simulations of dynamic rupture on megathrust/splay fault systems that address the mechanical plausibility and characteristics of coseismic slip on splay faults. As a case study, we consider a possible earthquake scenario for the Nankai subduction zone. Previous dynamic rupture simulations (Wendt et. al., 2009) considered a splay fault that cuts through the overriding crust and reaches the surface more than 100 km away from the trench. We examine instead a model geometry based on seismic reflection profiling in Nankai, in which a megasplay fault branches off at around 50 km from the trench, cuts through the sedimentary wedge and reaches the seafloor at about 25 km from the trench. We first investigate the 2D dynamics of this splay fault system, governed by slip-weakening friction law. We compare rupture propagation on this faulting model using a finite-element code (PyLith) and a spectral element code (SEM2DPACK). We report on the favorable conditions for splay faults to rupture, the degree of slip partitioning and the effects of arresting rupture at different depths on the plate-boundary. We also show how well our work correlates with previous works on branched fault systems. We then select a small set of 3D simulations that illustrates the main aspects. Finally the effect of velocity-strengthening fault properties at shallow depth is studied in the context of rate-and-state friction, with particular emphasis on the conditions to produce

  19. 3D Dynamic Rupture Simulations Across Interacting Faults: the Mw7.0, 2010, Haiti Earthquake (United States)

    Douilly, R.; Aochi, H.; Calais, E.; Freed, A. M.; Aagaard, B.


    The mechanisms controlling rupture propagation between fault segments during an earthquake are key to the hazard posed by fault systems. Rupture initiation on a fault segment sometimes transfers to a larger fault, resulting in a significant event (e.g.i, 2002 M7.9Denali and 2010 M7.1 Darfield earthquakes). In other cases rupture is constrained to the initial segment and does not transfer to nearby faults, resulting in events of moderate magnitude. This is the case of the 1989 M6.9 Loma Prieta and 2010 M7.0 Haiti earthquakes which initiated on reverse faults abutting against a major strike-slip plate boundary fault but did not propagate onto it. Here we investigatethe rupture dynamics of the Haiti earthquake, seeking to understand why rupture propagated across two segments of the Léogâne fault but did not propagate to the adjacenent Enriquillo Plantain Garden Fault, the major 200 km long plate boundary fault cutting through southern Haiti. We use a Finite Element Model to simulate the nucleation and propagation of rupture on the Léogâne fault, varying friction and background stress to determine the parameter set that best explains the observed earthquake sequence. The best-fit simulation is in remarkable agreement with several finite fault inversions and predicts ground displacement in very good agreement with geodetic and geological observations. The two slip patches inferred from finite-fault inversions are explained by the successive rupture of two fault segments oriented favorably with respect to the rupture propagation, while the geometry of the Enriquillo fault did not allow shear stress to reach failure. Although our simulation results replicate well the ground deformation consistent with the geodetic surface observation but convolving the ground motion with the soil amplification from the microzonation study will correctly account for the heterogeneity of the PGA throughout the rupture area.

  20. Rupture, waves and earthquakes (United States)

    UENISHI, Koji


    Normally, an earthquake is considered as a phenomenon of wave energy radiation by rupture (fracture) of solid Earth. However, the physics of dynamic process around seismic sources, which may play a crucial role in the occurrence of earthquakes and generation of strong waves, has not been fully understood yet. Instead, much of former investigation in seismology evaluated earthquake characteristics in terms of kinematics that does not directly treat such dynamic aspects and usually excludes the influence of high-frequency wave components over 1 Hz. There are countless valuable research outcomes obtained through this kinematics-based approach, but “extraordinary” phenomena that are difficult to be explained by this conventional description have been found, for instance, on the occasion of the 1995 Hyogo-ken Nanbu, Japan, earthquake, and more detailed study on rupture and wave dynamics, namely, possible mechanical characteristics of (1) rupture development around seismic sources, (2) earthquake-induced structural failures and (3) wave interaction that connects rupture (1) and failures (2), would be indispensable. PMID:28077808

  1. Rupture, waves and earthquakes. (United States)

    Uenishi, Koji


    Normally, an earthquake is considered as a phenomenon of wave energy radiation by rupture (fracture) of solid Earth. However, the physics of dynamic process around seismic sources, which may play a crucial role in the occurrence of earthquakes and generation of strong waves, has not been fully understood yet. Instead, much of former investigation in seismology evaluated earthquake characteristics in terms of kinematics that does not directly treat such dynamic aspects and usually excludes the influence of high-frequency wave components over 1 Hz. There are countless valuable research outcomes obtained through this kinematics-based approach, but "extraordinary" phenomena that are difficult to be explained by this conventional description have been found, for instance, on the occasion of the 1995 Hyogo-ken Nanbu, Japan, earthquake, and more detailed study on rupture and wave dynamics, namely, possible mechanical characteristics of (1) rupture development around seismic sources, (2) earthquake-induced structural failures and (3) wave interaction that connects rupture (1) and failures (2), would be indispensable.

  2. Complete Achilles tendon ruptures. (United States)

    Landvater, S J; Renström, P A


    Achilles tendon ruptures can be treated nonsurgically in the nonathletic or low-end recreational athletic patient, particularly those more than 50 years of age, provided the treating physician does not delay in the diagnosis and treatment (preferably less than 48 hrs and possibly less than 1 week). The patient should be advised of the higher incidence of re-rupture of the tendon when treated nonsurgically. Surgical treatment is recommended for patients who are young and athletic. This is particularly true because the major criticism of surgical treatment has been the complication rate, which has decreased to a low level and to a mild degree, usually not significantly affecting the repair over time. Surgical treatment in these individuals seems to be superior not only in regard to re-rupture but also in assuring the correct apposition of the tendon ends and in placing the necessary tension on the tendon to secure appropriate orientation of the collagen fibers. This in turn allows them to regain full strength, power, endurance, and an early return to sports. Surgery is also recommended for late diagnosed ruptures where there is significant lengthening of the tendon. Surgical technique should involve a medial incision to avoid the sural nerve, absorbable suture, and augmentation with fascia or tendon where there is a gap or late rupture. Postoperatively, the immobilization should be 7 to 10 days in a splint. A walking boot with early motion in plantar flexion or a short leg cast with the tendon under slight tension should thereafter be used for 4 to 5 weeks. An early and well-supervised rehabilitation program should be initiated to restore the patient to the preinjury activity level.

  3. Rupture of the plantar fascia. (United States)

    Pai, V S


    Rupture of the plantar fascia in athletes engaged in sports that require running and jumping has been reported. However, spontaneous degenerative rupture of the plantar fascia is not well documented in the literature. This paper reports a patient with degenerative rupture of the plantar fascia.

  4. Coupling geodynamic earthquake cycles and dynamic ruptures (United States)

    van Zelst, Iris; van Dinther, Ylona; Gabriel, Alice-Agnes; Heuret, Arnauld


    Studying the seismicity in a subduction zone and its effects on tsunamis requires diverse modelling methods that span spatial and temporal scales. Hundreds of years are necessary to build the stresses and strengths on a fault, while consequent earthquake rupture propagation is determined by both these initial fault conditions and the feedback of seismic waves over periods of seconds up to minutes. This dynamic rupture displaces the sea floor, thereby causing tsunamis. The aim of the ASCETE (Advanced Simulations of Coupled Earthquake and Tsunami Events) project is to study all these aspects and their interactions. Here, we present preliminary results of the first aspects in this modelling chain: the coupling of a seismo-thermo-mechanical (STM) code to the dynamic rupture model SeisSol. STM models of earthquake cycles have the advantage of solving multiple earthquake events in a self-consistent manner concerning stress, strength and geometry. However, the drawback of these models is that they often lack in spatial or temporal resolution and do not include wave propagation. In contrast, dynamic rupture models solve for frictional failure coupled to seismic wave propagation. We use the software package SeisSol ( based on an ADER-DG discretization allowing high-order accuracy in space and time as well as flexible tetrahedral meshing. However, such simulations require assumptions on the initial fault stresses and strengths and its geometry, which are hard to constrain due to the lack of near-field observations and the complexity of coseismic conditions. By adapting the geometry as well as the stress and strength properties of the self-consistently developing non-finite fault zones from the geodynamic models as initial conditions for the dynamic rupture models, the advantages of both methods are exploited and modelling results may be compared. Our results show that a dynamic rupture can be triggered spontaneously and that the propagating rupture is

  5. Rupture Process During the 2015 Illapel, Chile Earthquake: Zigzag-Along-Dip Rupture Episodes (United States)

    Okuwaki, Ryo; Yagi, Yuji; Aránguiz, Rafael; González, Juan; González, Gabriel


    We constructed a seismic source model for the 2015 M W 8.3 Illapel, Chile earthquake, which was carried out with the kinematic waveform inversion method adopting a novel inversion formulation that takes into account the uncertainty in the Green's function, together with the hybrid backprojection method enabling us to track the spatiotemporal distribution of high-frequency (0.3-2.0 Hz) sources at high resolution by using globally observed teleseismic P-waveforms. A maximum slip amounted to 10.4 m in the shallow part of the seismic source region centered 72 km northwest of the epicenter and generated a following tsunami inundated along the coast. In a gross sense, the rupture front propagated almost unilaterally to northward from the hypocenter at event at the down-dip edge of the seismic source region. High-frequency sources tends to be distributed at deeper parts of the slip area, a pattern also documented in other subduction zone megathrust earthquakes that may reflect the heterogeneous distribution of fracture energy or stress drop along the fault. The weak excitation of high-frequency radiation at the termination of rupture may represent the gradual deceleration of rupture velocity at the transition zone of frictional property or stress state between the megathrust rupture zone and the swarm area.

  6. Rupture of Renal Transplant

    Directory of Open Access Journals (Sweden)

    Shona Baker


    Full Text Available Background. Rupture of renal allograft is a rare and serious complication of transplantation that is usually attributed to acute rejection, acute tubular necrosis, or renal vein thrombosis. Case Presentation. LD, a 26-year-old male with established renal failure, underwent deceased donor transplantation using kidney from a 50-year-old donor with acute kidney injury (Cr 430 mmol/L. LD had a stormy posttransplant recovery and required exploration immediately for significant bleeding. On day three after transplant, he developed pain/graft swelling and another significant haemorrhage with cardiovascular compromise which did not respond to aggressive resuscitation. At reexploration, the renal allograft was found to have a longitudinal rupture and was removed. Histology showed features of type IIa Banff 97 acute vascular rejection, moderate arteriosclerosis, and acute tubular necrosis. Conclusion. Possible ways of avoiding allograft rupture include use of well-matched, good quality kidneys; reducing or managing risk factors that would predispose to delayed graft function; ensuring a technically satisfactory transplant procedure with short cold and warm ischemia times; and avoiding large donor-recipient age gradients.

  7. Bayesian rupture imaging in a complex medium: The 29 May 2012 Emilia, Northern Italy, earthquake (United States)

    Causse, Mathieu; Cultrera, Giovanna; Moreau, Ludovic; Herrero, André; Schiappapietra, Erika; Courboulex, Françoise


    We develop a new approach to image earthquake rupture from strong motion data. We use a large data set of aftershock waveforms, interpolated over the seismic fault to obtain Green's function approximations. Next we deploy a Bayesian inversion method to characterize the slip distribution, the rupture velocity, the slip duration, and their uncertainties induced by errors in the Green's functions. The method is applied to the 29 May 2012 Mw 6 Emilia earthquake, which ruptured a fault buried below the Po Plain sediments (Northern Italy). Despite the particularly complex wave propagation, the near-field strong motion observations are well reproduced with 15 rupture parameters. The rupture and slip velocities were notably slow ( 0.5 Vs and earthquake rupture studies in areas where numerical simulations suffer from imprecise knowledge of the velocity structure.

  8. Ruptured Pebbles - a coseismic and paleoseismic indicator? (United States)

    Weismüller, Christopher; Reicherter, Klaus


    To increase the understanding of paleo-earthquakes and deformation patterns, and the propagation of surface waves in the proximity of active faults, we use the mainly disregarded features of ruptured or broken pebbles within in a clayey matrix. Deformation of unconsolidated sediments (alluvium, colluvium) due to earthquake ruptures is a long investigated topic, including the degradation of the fault scarp. However, during many trenching studies aligned pebbles along the fault planes have been described, and attributed to coseismic deformation. Over the last decades, we have found many ruptured pebbles in trenches at active faults with historic earthquakes, but also aligned (rotated?) pebbles. Here, we describe ruptured pebbles from a Pleistocene debris flow near the coastline between the towns Carboneras and Mojácar (SE Spain), East of the Sierra Cabrera. The outcrop is on-fault at the transition of the active Carboneras and Palomares faults (major historical earthquakes with M 7 in 1518 and 1522), implying proximity to the earthquakes epicenters. The Carboneras (NE-SW), Gafarillos (E-W) and Palomares (NNE-SSW) faults form major faults in eastern Andalucia. The outcrop contains ruptured pebbles in an only slightly consolidated, Pleistocene debris flow with 50 % matrix content. Similar near-fault ruptured pebbles have already been observed in the Carrizales quarry near Baelo Claudia, S Spain, and many other sites (e.g., Italy, Greece, Russia), but always in the proximity of active faults. We measured the fractures of 100 pebbles as planes, if possible, or trend, in case no measureable plane was accessible. Complementary 3D-models of the outcrop and each ruptured pebble were created using Structure from Motion, allowing us to further study the pebbles morphology and geometry. Mode II and conjugate fractures are prevailing in the pebbles and the lack of surface-loading such as striations and dissolution pits neglects clast-interaction. Un-cemented shear planes

  9. Cohesive zone length of metagabbro at supershear rupture velocity (United States)

    Fukuyama, Eiichi; Xu, Shiqing; Yamashita, Futoshi; Mizoguchi, Kazuo


    We investigated the shear strain field ahead of a supershear rupture. The strain array data along the sliding fault surfaces were obtained during the large-scale biaxial friction experiments at the National Research Institute for Earth Science and Disaster Resilience. These friction experiments were done using a pair of meter-scale metagabbro rock specimens whose simulated fault area was 1.5 m × 0.1 m. A 2.6-MPa normal stress was applied with loading velocity of 0.1 mm/s. Near-fault strain was measured by 32 two-component semiconductor strain gauges installed at an interval of 50 mm and 10 mm off the fault and recorded at an interval of 1 MHz. Many stick-slip events were observed in the experiments. We chose ten unilateral rupture events that propagated with supershear rupture velocity without preceding foreshocks. Focusing on the rupture front, stress concentration was observed and sharp stress drop occurred immediately inside the ruptured area. The temporal variation of strain array data is converted to the spatial variation of strain assuming a constant rupture velocity. We picked up the peak strain and zero-crossing strain locations to measure the cohesive zone length. By compiling the stick-slip event data, the cohesive zone length is about 50 mm although it scattered among the events. We could not see any systematic variation at the location but some dependence on the rupture velocity. The cohesive zone length decreases as the rupture velocity increases, especially larger than √{2} times the shear wave velocity. This feature is consistent with the theoretical prediction.

  10. Multiple branching rupture of the 2009 Tonga-Samoa earthquake (United States)

    Fan, Wenyuan; Shearer, Peter M.; Ji, Chen; Bassett, Dan


    Several source models have been proposed to explain the enigmatic 2009 Tonga-Samoa earthquake. The long-period data require a composite source model and can be fit with a normal-faulting subevent followed by one or more reverse-faulting subevents. The short-period data, in contrast, indicate a more compact rupture pattern around the epicenter. The lack of a unified source model reflects the complexity of the event. We analyze the spatiotemporal evolution of this earthquake with P wave back-projection from globally distributed stations in different frequency bands (low frequency: 0.05-0.2 Hz, high frequency: 0.2-2 Hz) and a multiple moment tensor inversion. The rupture propagation revealed by back-projection exhibits frequency-dependent behavior, with two branches of high-frequency-enriched bilateral rupture around the epicenter and a high-frequency-deficient rupture branch at the subduction interface. A composite source model with one Mw 8.0 normal-faulting earthquake east of the trench axis (seaward) followed by one Mw 8.1 reverse-faulting earthquake along the subduction interface west of the trench axis (landward) can explain the very long period data (200˜500 s). Combined with high-resolution swath bathymetry data, the back-projection images show that the azimuth of rupture branches east of the trench axis were controlled by the geometry of bending-related faults on the Pacific plate and that the rupture branch west of the trench axis may correlate with the along-strike fore-arc segmentation. The rupture along the subduction interface was triggered by the seaward rupture and a partially subducted normal fault may have played a key role in facilitating the triggering. The apparent normal-reverse faulting interactions pose a higher seismic risk to this region than their individual strands at the northernmost corner of the Tonga subduction zone.

  11. The Rupture Behaviour Of Woven Fabrics Containing Kevlar Fibres (United States)

    Mao, N.; Qu, J.; Darley, M.; Lingard, S.


    Woven fabrics containing high performance fibres are frequently used in spacecraft structures and the rupture behaviour of these fabrics heavily influences the performance of its final products. However, the initiation and propagation of a ruptured fracture in the woven fabrics is not clear and the interpretation of the results from different tear testing methods varies. Currently there is a lack of knowledge about both the characteristics of tear propagation woven fabrics containing high performance fibres such as Kevlar and the influence of the fabric structural parameters on the rupture behaviour of the fabrics; this knowledge gap creates difficulties for the engineering design and selection of suitable fabric materials to meet specific requirements in each application case involving such woven fabrics. In this paper, the tear propagations in a polyurethane-coated woven fabric containing Kevlar fibres based on two different tear testing standards are examined; the mechanism of tear propagation in woven fabrics and the influences of tear testing design on the interpretation of the results from different tear testing methods are discussed. It is expected that the results will guide both the engineering design of Kevlar woven fabric structures and the evaluation of the fabric performance.

  12. Source rupture processes of the 2016 Kumamoto, Japan, earthquakes estimated from strong-motion waveforms (United States)

    Kubo, Hisahiko; Suzuki, Wataru; Aoi, Shin; Sekiguchi, Haruko


    The detailed source rupture process of the M 7.3 event (April 16, 2016, 01:25, JST) of the 2016 Kumamoto, Japan, earthquakes was derived from strong-motion waveforms using multiple-time-window linear waveform inversion. Based on the observations of surface ruptures, the spatial distribution of aftershocks, and the geodetic data, a realistic curved fault model was developed for source-process analysis of this event. The seismic moment and maximum slip were estimated as 5.5 × 1019 Nm ( M w 7.1) and 3.8 m, respectively. The source model of the M 7.3 event had two significant ruptures. One rupture propagated toward the northeastern shallow region at 4 s after rupture initiation and continued with large slips to approximately 16 s. This rupture caused a large slip region 10-30 km northeast of the hypocenter that reached the caldera of Mt. Aso. Another rupture propagated toward the surface from the hypocenter at 2-6 s and then propagated toward the northeast along the near surface at 6-10 s. A comparison with the result of using a single fault plane model demonstrated that the use of the curved fault model led to improved waveform fit at the stations south of the fault. The source process of the M 6.5 event (April 14, 2016, 21:26, JST) was also estimated. In the source model obtained for the M 6.5 event, the seismic moment was 1.7 × 1018 Nm ( M w 6.1), and the rupture with large slips propagated from the hypocenter to the surface along the north-northeast direction at 1-6 s. The results in this study are consistent with observations of the surface ruptures. [Figure not available: see fulltext. Caption: .

  13. Insights into rupture processes of a laboratory-earthquake in dry and lubricated faults (United States)

    Bayart, Elsa; Svetlizky, Ilya; Fineberg, Jay


    Our understanding of the dynamics of earthquakes requires us to understand the mechanisms of transition from static to sliding friction. The weakening of a fault is mediated by the propagation of rapid interfacial ruptures (earthquakes) that detach the solid contacts forming the frictional interface. By measuring the real contact area and strain fields near rough frictional interfaces, we have shown that these ruptures correspond to true shear cracks [1]. In particular, dynamic ruptures may spontaneously arrest at various locations along the interface. We show that a fracture-mechanics-based criterion can predict the location of the rupture arrest [2]. These results shed light on the selection of an earthquake's magnitude and arrest. Another interesting question is how interstitial fluids act to weaken a fault. By performing stick-slip experiments where the contacting surfaces are covered by a thin lubricating layer, we show that the established framework of fracture mechanics can also describe the measured strain fields when rupture of the interface takes place. A surprising result is that, although reducing the frictional strength of the interface (friction coefficient), lubricants actually significantly increase the fracture energy (amount of dissipated energy) during rupture. Thus surface lubrication, while strongly reducing the residual stresses in the wake of rupture propagation, actually toughens the contacting surfaces. [1] Svetlizky, I. & Fineberg, J. Classical shear cracks drive the onset of dry frictional motion. Nature 509, 205-208 (2014). [2] Bayart, E., Svetlizky, I. & Fineberg, J. Fracture mechanics determine the lengths of interface ruptures that mediate frictional motion. Nature Physics (2015).

  14. Effects of Pre-Stress State and Rupture Velocity on Dynamic Fault Branching (United States)

    Kame, N.; Rice, J. R.; Dmowska, R.


    We consider a mode II rupture which propagates along a planar main fault and encounters an intersection with a branching fault that makes an angle with the main fault. Within a formulation that allows the failure path to be dynamically self-chosen, we study the following questions: Does the rupture start along the branch? Does it continue? Which side is most favored for branching, the extensional or compressional? Does rupture continue on the main fault too? What path is finally self-chosen? Failure in the modeling is described by a slip-weakening law for which the peak and residual strength, and strength at any particular amount of slip, is proportional to normal stress. We use the elastodynamic boundary integral equation method to allow simulations of rupture along the branched fault system. Our results show that dynamic stresses around the rupturing fault tip, which increase with rupture velocity at locations off the main fault plane, relative to those on it, could initiate rupture on a branching fault. As suggested by prior work [Poliakov, Dmowska and Rice, 2002,], whether a branching rupture, once begun, can be continued to a larger scale depends on principal stress directions in the pre-stress state and on rupture velocity. The most favored side for rupture transferring on a branching fault switches from the extensional side to the compressive side as we consider progressively shallower angles of the direction of maximum pre-compression with the main fault. Simultaneous rupturing on both faults is usually difficult for a narrow branching angle due to strong stress interaction between faults, which discourages rupture continuation on the other side. However, it can be activated by enhanced dynamic stressing when the rupture velocity is very near the limiting velocity (Rayleigh wave velocity for mode II). It can also be activated when the branching angle is wide because of decreasing stress interaction between faults

  15. A case of testicular rupture


    野俣, 浩一郎; 林, 幹男


    A case of testicular rupture is reported. A 26-year-old man was referred to our hospital because of testicular trauma. Ultrasound of the testis was performed preoperatively. Ultrasonography revealed a disruption of the tunica albuginea and dense clusters of echoes in the tunica vaginalis. In the case of acute testicular trauma, this echo pattern suggests testicular rupture.

  16. Which Dynamic Rupture Parameters can be Resolved? (United States)

    Peyrat, S.; Olsen, K.; Madariaga, R.


    We use finite-difference simulations in models of the 1992 Mw 7.3 Landers earthquake to examine which dynamic rupture parameters may be recovered for large crustal earthquakes. By trial-and-error inversion Peyrat et al. (2001) found two simple models with constant slip-weakening friction which generated a satisfactory fit between synthetic and observed strong motion data: an asperity model, with spatially-varying initial stress and constant yield stress, and a barrier model with constant initial stress and spatially-varying yield stress. However, there is some evidence from inversion of seismic data for large earthquakes (i.e., Ide and Takeo, 1997, for the 1995 Kobe earthquake), that the slip-weakening distance Dc may vary spatially. In particular, Ide and Takeo found a larger Dc in the shallower parts of the crust compared to the deeper parts. Possible causes of such variation include the increase of elastic rigidity with depth and a fundamentally different friction in the near-surface layers. Here, we examine the effects of laterally and vertically varying Dc on the strong motion synthetics computed by our dynamic rupture models. We generate an alternative barrier model with constant initial and yield stress but spatially-varying Dc which, as our two previous rupture models of the Landers event, generate synthetics in agreement with strong motion data. Thus, we have constructed three well-posed mechanical models of the Landers earthquake that satisfy available strong motion data and which are end-members of a large family of dynamically correct models. Our findings confirm an earlier hypothesis that barrier and asperity models of an earthquake generate similar signature in the seismic radiation (Madariaga, 1979). Therefore, it may not be possible to separate stress and Dc using rupture modeling. Instead, we propose to characterize dynamic rupture propagation by the local non-dimensional parameter κ introduced by Madariaga and Olsen (2000), which is expressed in

  17. Geologic and structural controls on rupture zone fabric: A field-based study of the 2010 Mw 7.2 El Mayor–Cucapah earthquake surface rupture (United States)

    Teran, Orlando; Fletcher, John L.; Oskin, Michael; Rockwell, Thomas; Hudnut, Kenneth W.; Spelz, Ronald; Akciz, Sinan; Hernandez-Flores, Ana Paula; Morelan, Alexander


    We systematically mapped (scales >1:500) the surface rupture of the 4 April 2010 Mw (moment magnitude) 7.2 El Mayor-Cucapah earthquake through the Sierra Cucapah (Baja California, northwestern Mexico) to understand how faults with similar structural and lithologic characteristics control rupture zone fabric, which is here defined by the thickness, distribution, and internal configuration of shearing in a rupture zone. Fault zone thickness and master fault dip are strongly correlated with many parameters of rupture zone fabric. Wider fault zones produce progressively wider rupture zones and both of these parameters increase systematically with decreasing dip of master faults, which varies from 20° to 90° in our dataset. Principal scarps that accommodate more than 90% of the total coseismic slip in a given transect are only observed in fault sections with narrow rupture zones (Sierra Cucapah are those developed above buried low angle faults due to the transfer of slip to widely distributed steeper faults, which are mechanically more favorably oriented. The results from this study show that the measureable parameters that define rupture zone fabric allow for testing hypotheses concerning the mechanics and propagation of earthquake ruptures, as well as for siting and designing facilities to be constructed in regions near active faults.

  18. Rupture process of the 2016 Kumamoto earthquake in relation to the thermal structure around Aso volcano (United States)

    Yagi, Yuji; Okuwaki, Ryo; Enescu, Bogdan; Kasahara, Amato; Miyakawa, Ayumu; Otsubo, Makoto


    We constructed the rupture process model for the 2016 Kumamoto, Japan, earthquake from broadband teleseismic body waveforms (P-waves) by using a novel waveform inversion method that takes into account the uncertainty of Green's function. The estimated source parameters are: seismic moment = 5.1 × 1019 Nm (Mw = 7.1), fault length = 40 km, and fault width = 15 km. The mainshock rupture mainly propagated northeastward from the epicenter, for about 30 km, along an active strike-slip fault. The rupture propagation of the mainshock decelerated and terminated near the southwest side of the Aso volcano; the aftershock activity was low around the northeastern edge of the major slip area. Our results suggest that the rupture process of the mainshock and the distribution of aftershocks were influenced by the high-temperature area around the magma chamber of Mt. Aso.

  19. Splenic rupture following colonoscopy

    Institute of Scientific and Technical Information of China (English)

    Juan Francisco Guerra; Ignacio San Francisco; Fernando Pimentel; Luis Ibanez


    Colonoscopy is a safe and routinely performed diagnostic and therapeutic procedure for different colorectal diseases. Although the most common complications are bleeding and perforation, extracolonic or visceral injuries have also been described. Splenic rupture is a rare complication following colonoscopy, with few cases reported. We report a 60-year-old female who presented to surgical consultation 8 h after a diagnostic colonoscopy. Clinical, laboratory and imaging findings were suggestive for a massive hemoperitoneum. At surgery, an almost complete splenic disruption was evident, and an urgent splenectomy was performed. After an uneventful postoperative period, she was discharged home. Splenic injury following colonoscopy is considered infrequent. Direct trauma and excessive traction of the splenocolic ligament can explain the occurrence of this complication. Many times the diagnosis is delayed because the symptoms are due to colonic insufflation, so the most frequent treatment is an urgent splenectomy. A high index of suspicion needs an early diagnosis and adequate therapy.

  20. Blunt traumatic diaphragmatic rupture

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Nogueira


    Full Text Available Traumatic injury of the diaphragm ranges from 0.6 to 1.2% and rise up to 5%among patients who were victims of blunt trauma and underwent laparotomy.Clinical suspicion associated with radiological assessment contributes to earlydiagnosis. Isolated diaphragmatic injury has a good prognosis. Generallyworse outcomes are associated with other trauma injuries. Bilateral andright diaphragmatic lesions have worse prognosis. Multi detector computed tomography (MDCT scan of the chest and abdomen provides better diagnosticaccuracy using the possibility of image multiplanar reconstruction. Surgicalrepair via laparotomy and/ or thoracotomy in the acute phase of the injury hasa better outcome and avoids chronic complications of diaphragmatic hernia.The authors present the case of a young male patient, victim of blunt abdominaltrauma due to motor vehicle accident with rupture of the diaphragm, spleenand kidney injuries. The diagnosis was made by computed tomography of thethorax and abdomen and was confirmed during laparotomy.

  1. Spontaneous Rupture of Pyometra

    Directory of Open Access Journals (Sweden)

    Fatemeh Mallah


    Full Text Available Spontaneous perforation is a very rare complication of pyometra. The clinical findings of perforated pyometra are similar to perforation of the gastrointestinal tract and other causes of acute abdomen. In most cases, a correct and definite diagnosis can be made only by laparotomy. We report two cases of diffuse peritonitis caused by spontaneous perforated pyometra. The first case is a 78-year-old woman with abdominal pain for which laparotomy was performed because of suspected incarcerated hernia. The second case is a 61-year-old woman with abdominal pain for which laparotomy was performed because of symptoms of peritonitis. At laparotomy of both cases, 1 liter of pus with the source of uterine was found in the abdominal cavity. The ruptured uterine is also detected. More investigations revealed no malignancy as the reason of the pyometra.

  2. Spontaneous Rupture of Pyometra (United States)

    Mallah, Fatemeh; Eftekhar, Tahere; Naghavi-Behzad, Mohammad


    Spontaneous perforation is a very rare complication of pyometra. The clinical findings of perforated pyometra are similar to perforation of the gastrointestinal tract and other causes of acute abdomen. In most cases, a correct and definite diagnosis can be made only by laparotomy. We report two cases of diffuse peritonitis caused by spontaneous perforated pyometra. The first case is a 78-year-old woman with abdominal pain for which laparotomy was performed because of suspected incarcerated hernia. The second case is a 61-year-old woman with abdominal pain for which laparotomy was performed because of symptoms of peritonitis. At laparotomy of both cases, 1 liter of pus with the source of uterine was found in the abdominal cavity. The ruptured uterine is also detected. More investigations revealed no malignancy as the reason of the pyometra. PMID:24024054

  3. Mucus Rupture in A Collapsed airway: An Experimental Study (United States)

    Hu, Yingying; Bian, Shiyao; Grotberg, James B.


    Mucus plugs can completely obstruct an airway. Difficulty in mucus clearance results in lost gas exchange and inflammation. Non-Newtonian properties of mucus, yielding stress and shear-thinning, play significant roles in mucus clearance. We use aqueous carbopol 940 as a mucus stimulant to study clearance of a mucus plug with properties of yielding stress and shear-thinning in a bench-top experiment. A collapsed airway of the 12th generation in a human lung is simulated in a two-dimensional PDMS channel. A stable pressure drop is set along the plug to drive rupture. A micro-PIV technique is used to acquire velocity fields during the rupture process. A yielding pressure drop (initiating plug yielding) is nearly independent of initial plug length. Plug rupture can occur by focused deformation along the centerline or by total plug propagation where the trailing film is thicker than the precursor film. Maximum velocity appears at the rupture moment, and increases at higher pressure drop or smaller plug length. The wall shear gradient can undergo a rapid reversal when rupture occurs, possibly an injurious event to underlying airway epithelial cells. This work is supported by NIH: HL84370 and HL85156.

  4. Dynamic rupture in a damage-breakage rheology model (United States)

    Lyakhovsky, Vladimir; Ben-Zion, Yehuda; Ilchev, Assen; Mendecki, Aleksander


    We present a thermodynamically based formulation for modelling dynamic rupture processes in the brittle crust using a continuum damage-breakage rheology. The model combines aspects of a continuum viscoelastic damage framework for brittle solids with a continuum breakage mechanics for granular flow within dynamically generated slip zones. The formulation accounts for the density of distributed cracking and other internal flaws in damaged rocks with a scalar damage parameter, and addresses the grain size distribution of a granular phase in the slip zone with a breakage parameter. A dynamic brittle instability is associated with a critical level of damage in the solid, leading to loss of convexity of the solid strain energy, localization and transition to a granular phase associated with lower energy level. The continuum damage-breakage rheology model treats the localization to a slip zone at the onset of dynamic rupture and post-failure recovery process as phase transitions between solid and granular states. The model generates sub- and supershear rupture velocities and pulse-type ruptures seen also in frictional models, and additional important features such as strong dynamic changes of volumetric strain near the rupture front and diversity of nucleation mechanisms. The propagation of rupture front and slip accumulation at a point are correlated with sharp dynamic dilation followed by a gradual decay to a level associated with the final volumetric change associated with the granular phase transition in the slipping zone. The local brittle failure process associated with the solid-granular transition is expected to produce isotropic radiation in addition to the deviatoric terms. The framework significantly extends the ability to model brittle processes in complex geometrical structures and allows analysing the roles of gouge thickness and other parameters on nucleation, rupture and radiation characteristics.

  5. Mechanics of cutaneous wound rupture. (United States)

    Swain, Digendranath; Gupta, Anurag


    A cutaneous wound may rupture during healing as a result of stretching in the skin and incompatibility at the wound-skin interface, among other factors. By treating both wound and skin as hyperelastic membranes, and using a biomechanical framework of interfacial growth, we study rupturing as a problem of cavitation in nonlinear elastic materials. We obtain analytical solutions for deformation and residual stress field in the skin-wound configuration while emphasizing the coupling between wound rupture and wrinkling in the skin. The solutions are analyzed in detail for variations in stretching environment, healing condition, and membrane stiffness.

  6. Elbow tendinopathy and tendon ruptures: epicondylitis, biceps and triceps ruptures. (United States)

    Rineer, Craig A; Ruch, David S


    Lateral and medial epicondylitis are common causes of elbow pain in the general population, with the lateral variety being more common than the medial by a ratio reportedly ranging from 4:1 to 7:1. Initially thought to be an inflammatory condition, epicondylitis has ultimately been shown to result from tendinous microtearing followed by an incomplete reparative response. Numerous nonoperative and operative treatment options have been employed in the treatment of epicondylitis, without the emergence of a single, consistent, universally accepted treatment protocol. Tendon ruptures about the elbow are much less frequent, but result in more significant disability and loss of function. Distal biceps tendon ruptures typically occur in middle-aged males as a result of an event that causes a sudden, eccentric contraction of the biceps. Triceps tendon ruptures are exceedingly rare but usually have a similar etiology with a forceful eccentric contraction of the triceps that causes avulsion of the tendon from the olecranon. The diagnosis of these injuries is not always readily made. Complete ruptures of the biceps or triceps tendons have traditionally been treated surgically with good results. With regard to biceps ruptures, there continues to be debate about the best surgical approach, as well as the best method of fixation of tendon to bone. This article is not meant to be an exhaustive review of the broad topics of elbow tendinopathy and tendon ruptures, but rather is a review of recently published information on the topics that will assist the clinician in diagnosis and management of these conditions.

  7. Ruptured thought: rupture as a critical attitude to nursing research. (United States)

    Beedholm, Kirsten; Lomborg, Kirsten; Frederiksen, Kirsten


    In this paper, we introduce the notion of ‘rupture’ from the French philosopher Michel Foucault, whose studies of discourse and governmentality have become prominent within nursing research during the last 25 years. We argue that a rupture perspective can be helpful for identifying and maintaining a critical potential within nursing research. The paper begins by introducing rupture as an inheritance from the French epistemological tradition. It then describes how rupture appears in Foucault's works, as both an overall philosophical approach and as an analytic tool in his historical studies. Two examples of analytical applications of rupture are elaborated. In the first example, rupture has inspired us to make an effort to seek alternatives to mainstream conceptions of the phenomenon under study. In the second example, inspired by Foucault's work on discontinuity, we construct a framework for historical epochs in nursing history. The paper concludes by discussing the potential of the notion of rupture as a response to the methodological concerns regarding the use of Foucault-inspired discourse analysis within nursing research. We agree with the critique of Cheek that the critical potential of discourse analysis is at risk of being undermined by research that tends to convert the approach into a fixed method.

  8. Three-dimensional dynamic rupture simulations across interacting faults: The Mw7.0, 2010, Haiti earthquake (United States)

    Douilly, R.; Aochi, H.; Calais, E.; Freed, A. M.


    The mechanisms controlling rupture propagation between fault segments during a large earthquake are key to the hazard posed by fault systems. Rupture initiation on a smaller fault sometimes transfers to a larger fault, resulting in a significant event (e.g., 2002 M7.9 Denali USA and 2010 M7.1 Darfield New Zealand earthquakes). In other cases rupture is constrained to the initial fault and does not transfer to nearby faults, resulting in events of more moderate magnitude. This was the case of the 1989 M6.9 Loma Prieta and 2010 M7.0 Haiti earthquakes which initiated on reverse faults abutting against a major strike-slip plate boundary fault but did not propagate onto it. Here we investigate the rupture dynamics of the Haiti earthquake, seeking to understand why rupture propagated across two segments of the Léogâne fault but did not propagate to the adjacent Enriquillo Plantain Garden Fault, the major 200 km long plate boundary fault cutting through southern Haiti. We use a finite element model to simulate propagation of rupture on the Léogâne fault, varying friction and background stress to determine the parameter set that best explains the observed earthquake sequence, in particular, the ground displacement. The two slip patches inferred from finite fault inversions are explained by the successive rupture of two fault segments oriented favorably with respect to the rupture propagation, while the geometry of the Enriquillo fault did not allow shear stress to reach failure.

  9. Geological structures control on earthquake ruptures: The Mw7.7, 2013, Balochistan earthquake, Pakistan (United States)

    Vallage, A.; Klinger, Y.; Lacassin, R.; Delorme, A.; Pierrot-Deseilligny, M.


    The 2013 Mw7.7 Balochistan earthquake, Pakistan, ruptured the Hoshab fault. Left-lateral motion dominated the deformation pattern, although significant vertical motion is found along the southern part of the rupture. Correlation of high-resolution (2.5 m) optical satellite images provided horizontal displacement along the entire rupture. In parallel, we mapped the ground rupture geometry at 1:500 scale. We show that the azimuth of the ground rupture distributes mainly between two directions, N216° and N259°. The direction N216° matches the direction of preexisting geologic structures resulting from penetrative deformation caused by the nearby Makran subduction. Hence, during a significant part of its rupture, the 2013 Balochistan rupture kept switching between a long-term fault front and secondary branches, in which existence and direction are related to the compressional context. It shows unambiguous direct interactions between different preexisting geologic structures, regional stress, and dynamic-rupture stress, which controlled earthquake propagation path.

  10. Spontaneous rupture of unscarred gravid uterus. (United States)

    Gurudut, Kolala S; Gouda, Hareesh S; Aramani, Sunil C; Patil, Raju H


    Rupture of gravid uterus during pregnancy is a rare entity. Overall incidence of rupture of uterus during pregnancy is 0.07%. The maternal and fetal prognoses are bad especially when the rupture occurs in an unscarred uterus. Fortunately, the sole major risk factor of spontaneous rupture of unscarred uterus is preventable, which is "multiparity." In this article, we report the death of a pregnant woman and her unborn child because of spontaneous rupture of unscarred uterus.

  11. Rupture directivity of the 2016, Amatrice and Norcia (central Italy) destructive earthquakes and their largest aftershocks (United States)

    Calderoni, Giovanna; Rovelli, Antonio; Di Giovambattista, Rita


    In this study, we investigate the along-strike rupture directivity of the five moderate-magnitude (Mw > 5.0) earthquakes of the 2016 central Italy seismic sequence and height aftershocks in the moment magnitude range from 4.4 to 4.8. Rupture directivity is estimated by deconvolving the observed spectra with spectra of EGF-type events. We have found that the August 24, Mw 6.0 Amatrice earthquake results in a bilateral along-strike rupture. However, directivity of this event is asymmetrical, the predominant rupture propagation being toward NNW. In contrast, the rupture of the October 30, Mw 6.5 Norcia earthquake propagated toward SSE. We have also found that the predominant rupture directivity toward SSE is a common feature of the majority of the investigates events, including the Mw 5.4 aftershock occurred less than one hour after the Amatrice earthquake. Along-strike rupture directivity in normal-faulting earthquakes in the Apennines has been already documented for the three largest events of the 1997 Umbria-Marche seismic sequence and for 70 earthquakes with moment magnitudes from 3.0 to 6.1 of the 2009 L'Aquila-Campotosto seismic sequence (the 2016 seismic activity filled the seismic gap between them). If we put together the results of the 1997 Umbria-Marche and the 2009 earthquakes, we find a significant spatial consistency of preferred directions of ruptures. Earthquakes to the south of Colfiorito up to Norcia show directivity toward SE-SSE, similarly to earthquakes in the southern part of the Campotosto fault and in the Paganica fault. In distinct contrast, from the northern tip of the Campotosto fault up to Amatrice the predominant rupture directivity is toward NNW-NW.

  12. Fan-head shear rupture mechanism as a source of off-fault tensile cracking (United States)

    Tarasov, Boris


    This presentation discusses the role of a recently identified fan-head shear rupture mechanism [1] in the creation of off-fault tensile cracks observed in earthquake laboratory experiments conducted on brittle photoelastic specimens [2,3]. According to the fan-mechanism the shear rupture propagation is associated with consecutive creation of small slabs in the fracture tip which, due to rotation caused by shear displacement of the fracture interfaces, form a fan-structure representing the fracture head. The fan-head combines such unique features as: extremely low shear resistance (below the frictional strength) and self-sustaining tensile stress intensification along one side of the interface. The variation of tensile stress within the fan-head zone is like this: it increases with distance from the fracture tip up to a maximum value and then decreases. For the initial formation of the fan-head high local stresses corresponding to the fracture strength should be applied in a small area, however after completions of the fan-head it can propagate dynamically through the material at low shear stresses (even below the frictional strength). The fan-mechanism allows explaining all unique features associated with the off-fault cracking process observed in photoelastic experiments [2,3]. In these experiments spontaneous shear ruptures were nucleated in a bonded, precut, inclined and pre-stressed interface by producing a local pressure pulse in a small area. Isochromatic fringe patterns around a shear rupture propagating along bonded interface indicate the following features of the off-fault tensile crack development: tensile cracks nucleate and grow periodically along one side of the interface at a roughly constant angle (about 80 degrees) relative to the shear rupture interface; the tensile crack nucleation takes place some distance behind the rupture tip; with distance from the point of nucleation tensile cracks grow up to a certain length within the rupture head zone

  13. Wave Propagation

    CERN Document Server

    Ferrarese, Giorgio


    Lectures: A. Jeffrey: Lectures on nonlinear wave propagation.- Y. Choquet-Bruhat: Ondes asymptotiques.- G. Boillat: Urti.- Seminars: D. Graffi: Sulla teoria dell'ottica non-lineare.- G. Grioli: Sulla propagazione del calore nei mezzi continui.- T. Manacorda: Onde nei solidi con vincoli interni.- T. Ruggeri: "Entropy principle" and main field for a non linear covariant system.- B. Straughan: Singular surfaces in dipolar materials and possible consequences for continuum mechanics

  14. Quadriceps and patellar tendon rupture. (United States)

    Ramseier, L E; Werner, C M L; Heinzelmann, M


    Ruptures of the patellar and/or quadriceps tendon are rare injuries that require immediate repair to re-establish knee extensor continuity and to allow early motion. We evaluated 36 consecutive patients with quadriceps or patellar tendon rupture between 1993 and 2000. There were 37 primary ruptures, 3 reruptures, 21 quadriceps and 19 patellar tendon ruptures. Follow up examination (>24 months postoperatively) included the patient's history, assessment of risk factors, clinical examination of both knees, isometric muscle strength measurements and three specific knee scores, Hospital for Special Surgery Score, Knee Society Score and Turba Score, and a short form SF-36. We evaluated 29 patients (26 men) with 33 ruptures (16 patellar tendon, 17 quadriceps tendon). Seven patients were lost to follow up. We found no difference between the range of motion and muscle strength when the injured leg was compared to the non-injured leg. Risk factors did not influence the four scores, patient satisfaction, pain, muscle strength or range of motion. Multiple injured patients had a significant reduction in muscle strength and circumference, however patient satisfaction did not differ to the non-multiple injured patient group.

  15. Widespread ground motion distribution caused by rupture directivity during the 2015 Gorkha, Nepal earthquake. (United States)

    Koketsu, Kazuki; Miyake, Hiroe; Guo, Yujia; Kobayashi, Hiroaki; Masuda, Tetsu; Davuluri, Srinagesh; Bhattarai, Mukunda; Adhikari, Lok Bijaya; Sapkota, Soma Nath


    The ground motion and damage caused by the 2015 Gorkha, Nepal earthquake can be characterized by their widespread distributions to the east. Evidence from strong ground motions, regional acceleration duration, and teleseismic waveforms indicate that rupture directivity contributed significantly to these distributions. This phenomenon has been thought to occur only if a strike-slip or dip-slip rupture propagates to a site in the along-strike or updip direction, respectively. However, even though the earthquake was a dip-slip faulting event and its source fault strike was nearly eastward, evidence for rupture directivity is found in the eastward direction. Here, we explore the reasons for this apparent inconsistency by performing a joint source inversion of seismic and geodetic datasets, and conducting ground motion simulations. The results indicate that the earthquake occurred on the underthrusting Indian lithosphere, with a low dip angle, and that the fault rupture propagated in the along-strike direction at a velocity just slightly below the S-wave velocity. This low dip angle and fast rupture velocity produced rupture directivity in the along-strike direction, which caused widespread ground motion distribution and significant damage extending far eastwards, from central Nepal to Mount Everest.

  16. Untreated silicone breast implant rupture

    DEFF Research Database (Denmark)

    Hölmich, Lisbet R; Vejborg, Ilse M; Conrad, Carsten


    Implant rupture is a well-known complication of breast implant surgery that can pass unnoticed by both patient and physician. To date, no prospective study has addressed the possible health implications of silicone breast implant rupture. The aim of the present study was to evaluate whether...... untreated ruptures are associated with changes over time in magnetic resonance imaging findings, serologic markers, or self-reported breast symptoms. A baseline magnetic resonance imaging examination was performed in 1999 on 271 women who were randomly chosen from a larger cohort of women having cosmetic...... breast implants for a median period of 12 years (range, 3 to 25 years). A follow-up magnetic resonance imaging examination was carried out in 2001, excluding women who underwent explantation in the period between the two magnetic resonance imaging examinations (n = 44). On the basis of these examinations...

  17. Protecting geothermal operations with rupture disks

    Energy Technology Data Exchange (ETDEWEB)

    Porter, D.W.


    Potential rupture disk applications in geothermal operations are reviewed. Several wells manifolded together, to form the geothermal feed, cause erratic pressure. Rupture disks are used for relief. Flash tanks are equipped with rupture disks. Brine separators, heat exchanger shells, and turbine casings are protected by rupture disks. An analysis of geothermal steam will determine the rupture disk metal. Reverse Buckling disks are recommended over tension loaded disks for dealing with geothermal pressure cycling. Erratic temperature suggests that metals which retain tensile strength with temperature be used (Inconel is mentioned). In summary, geothermal projects represent an excellent rupture disk market.

  18. Energy Partition During In-plane Dynamic Rupture on a Frictional Interface (United States)

    Needleman, A.; Shi, Z.; Ben-Zion, Y.


    We study properties of dynamic ruptures and the partition of energy between radiation and dissipative mechanisms using two-dimensional in-plane calculations with the finite element method. The model consists of two identical isotropic elastic media separated by an interface governed by rate- and state-dependent friction. Rupture is initiated by gradually overstressing a localized nucleation zone. Our simulations with model parameters representative of Homalite-100 indicate that different values of parameters controlling the velocity dependence of friction, the strength excess parameter and the length of the nucleation zone, can lead to the following four rupture modes: supershear crack-like rupture, subshear crack-like rupture, subshear single pulse and supershear train of pulses. High initial shear stress and weak velocity dependence of friction favor crack-like ruptures, while the opposite conditions favor the pulse mode. The rupture mode can switch from a subshear single pulse to a supershear train of pulses when the width of the nucleation zone increases. The elastic strain energy released over the same propagation distance by the different rupture modes has the following order: supershear crack, subshear crack, supershear train of pulses and subshear single pulse. The same order applies also to the ratio of kinetic energy (radiation) to total change of elastic energy for the different rupture modes. Decreasing the dynamic coefficient of friction increases the fraction of stored energy that is converted to kinetic energy. In the current study we use model parameters representative of rocks instead of Homalite-100, by modeling recent results of Kilgore et al. (2007) who measured and estimated various energy components in laboratory friction experiments with granite. We are also incorporating into the code ingredients that will allow us to study rupture properties and energy partition for cases with a bimaterial interface and dynamic generation of plastic strain

  19. Self-Rupturing Hermetic Valve (United States)

    Tucker, Curtis E., Jr.; Sherrit, Stewart


    For commercial, military, and aerospace applications, low-cost, small, reliable, and lightweight gas and liquid hermetically sealed valves with post initiation on/off capability are highly desirable for pressurized systems. Applications include remote fire suppression, single-use system-pressurization systems, spacecraft propellant systems, and in situ instruments. Current pyrotechnic- activated rupture disk hermetic valves were designed for physically larger systems and are heavy and integrate poorly with portable equipment, aircraft, and small spacecraft and instrument systems. Additionally, current pyrotechnically activated systems impart high g-force shock loads to surrounding components and structures, which increase the risk of damage and can require additional mitigation. The disclosed mechanism addresses the need for producing a hermetically sealed micro-isolation valve for low and high pressure for commercial, aerospace, and spacecraft applications. High-precision electrical discharge machining (EDM) parts allow for the machining of mated parts with gaps less than a thousandth of an inch. These high-precision parts are used to support against pressure and extrusion, a thin hermetically welded diaphragm. This diaphragm ruptures from a pressure differential when the support is removed and/or when the plunger is forced against the diaphragm. With the addition of conventional seals to the plunger and a two-way actuator, a derivative of this design would allow nonhermetic use as an on/off or metering valve after the initial rupturing of the hermetic sealing disk. In addition, in a single-use hermetically sealed isolation valve, the valve can be activated without the use of potential leak-inducing valve body penetrations. One implementation of this technology is a high-pressure, high-flow-rate rupture valve that is self-rupturing, which is advantageous for high-pressure applications such as gas isolation valves. Once initiated, this technology is self

  20. Spontaneous rupture of vaginal enterocele

    DEFF Research Database (Denmark)

    Svendsen, Jesper Hastrup; Galatius, H; Hansen, P K


    Spontaneous rupture of an enterocele is a rare complication. Only 24 cases including the present case have been reported in the literature. The patients were elderly and had had at least one vaginal operation. The patients were remarkably unaffected symptomatically on admission.......Spontaneous rupture of an enterocele is a rare complication. Only 24 cases including the present case have been reported in the literature. The patients were elderly and had had at least one vaginal operation. The patients were remarkably unaffected symptomatically on admission....

  1. Spontaneous rupture of vaginal enterocele

    DEFF Research Database (Denmark)

    Svendsen, Jesper Hastrup; Galatius, H; Hansen, P K


    Spontaneous rupture of an enterocele is a rare complication. Only 24 cases including the present case have been reported in the literature. The patients were elderly and had had at least one vaginal operation. The patients were remarkably unaffected symptomatically on admission.......Spontaneous rupture of an enterocele is a rare complication. Only 24 cases including the present case have been reported in the literature. The patients were elderly and had had at least one vaginal operation. The patients were remarkably unaffected symptomatically on admission....

  2. Simultaneous bilateral patellar tendon rupture

    Directory of Open Access Journals (Sweden)

    Diogo Lino Moura

    Full Text Available ABSTRACT Bilateral patellar tendon rupture is a rare entity, often associated with systemic diseases and patellar tendinopathy. The authors report a rare case of a 34-year-old man with simultaneous bilateral rupture of the patellar tendon caused by minor trauma. The patient is a retired basketball player with no past complaints of chronic knee pain and a history of steroid use. Surgical management consisted in primary end-to-end tendon repair protected temporarily with cerclage wiring, followed by a short immobilization period and intensive rehabilitation program. Five months after surgery, the patient was able to fully participate in sport activities.

  3. On the speed of fast and slow rupture fronts along frictional interfaces

    CERN Document Server

    Trømborg, Jørgen Kjoshagen; Thøgersen, Kjetil; Scheibert, Julien; Malthe-Sørenssen, Anders


    The transition from stick to slip at a dry frictional interface occurs through the breaking of the junctions between the two contacting surfaces. Typically, interactions between the junctions through the bulk lead to rupture fronts propagating from weak and/or highly stressed regions, whose junctions break first. Experiments find rupture fronts ranging from quasi-static fronts with speeds proportional to external loading rates, via fronts much slower than the Rayleigh wave speed, and fronts that propagate near the Rayleigh wave speed, to fronts that travel faster than the shear wave speed. The mechanisms behind and selection between these fronts are still imperfectly understood. Here we perform simulations in an elastic 2D spring--block model where the frictional interaction between each interfacial block and the substrate arises from a set of junctions modeled explicitly. We find that a proportionality between material slip speed and rupture front speed, previously reported for slow fronts, actually holds ac...

  4. Rupture of Achilles Tendon : Usefulness of Ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Nam Hyeon; Ki, Won Woo; Yoon, Kwon Ha; Kim, Song Mun; Shin, Myeong Jin [Ulsan Medical College, Ulsan (Korea, Republic of); Kwon, Soon Tae [Chungnam University College of Medicine, Daejeon (Korea, Republic of)


    To differentiate a complete rupture of Achilles tendon from an incomplete one which is important because its treatment is quite different. And it is necessary to know the exact site of the rupture preoperatively. Fifteen cases of fourteen patients which were diagnosed as Achilles tendon rupture by ultrasonography and surgery were reviewed. We compared sonographic rupture site with surgical findings. Ultrasonographic criteria for differentiation of complete and incomplete rupture was defined as follows : the discreteness, which means the proximal intervening hypoechogenicity to the interface echogenicity of distal margin of ruptured tendon : the slant sign, which represents the interface of ruptured distal margin which was seen over the 3/4 of the thickness of the tendon without intervening low echogeneicity : the invagination sign, which means the echogenic invagination from Kager triangle into posterior aspect of Achilles tendon over the half thickness of the tendon. The sites of complete tendon rupture were exactly corresponded to surgical finding in four cases of ten complete ruptures. And the discrepancy between sonographic and surgical findings in the site of complete rupture was 1.2 {+-} 0.4 cm in six cases. Three of ten complete ruptures showed the discreteness sign, all of ten showed the slant sign and two of ten showed the invagination sign. It is helpful to differentiate a complete from incomplete rupture of the Achilles tendon and to localize the site of the complete rupture with the ultrasonographic evaluation

  5. A Fault Evolution Model Including the Rupture Dynamic Simulation (United States)

    Wu, Y.; Chen, X.


    We perform a preliminary numerical simulation of seismicity and stress evolution along a strike-slip fault in a 3D elastic half space. Following work of Ben-Zion (1996), the fault geometry is devised as a vertical plane which is about 70 km long and 17 km wide, comparable to the size of San Andreas Fault around Parkfield. The loading mechanism is described by "backslip" method. The fault failure is governed by a static/kinetic friction law, and induced stress transfer is calculated with Okada's static solution. In order to track the rupture propagation in detail, we allow induced stress to propagate through the medium at the shear wave velocity by introducing a distance-dependent time delay to responses to stress changes. Current simulation indicates small to moderate earthquakes following the Gutenberg-Richter law and quasi-periodical characteristic large earthquakes, which are consistent with previous work by others. Next we will consider introducing a more realistic friction law, namely, the laboratory-derived rate- and state- dependent law, which can simulate more realistic and complicated sliding behavior such as the stable and unstable slip, the aseismic sliding and the slip nucleation process. In addition, the long duration of aftershocks is expected to be reproduced due to this time-dependent friction law, which is not available in current seismicity simulation. The other difference from previous work is that we are trying to include the dynamic ruptures in this study. Most previous study on seismicity simulation is based on the static solution when dealing with failure induced stress changes. However, studies of numerical simulation of rupture dynamics have revealed lots of important details which are missing in the quasi-static/quasi- dynamic simulation. For example, dynamic simulations indicate that the slip on the ground surface becomes larger if the dynamic rupture process reaches the free surface. The concentration of stress on the propagating crack

  6. Achilles tendon rupture; assessment of nonoperative treatment

    National Research Council Canada - National Science Library

    Barfod, Kristoffer Weisskirchner


    Acute Achilles tendon rupture is a frequent and potentially disabling injury. Over the past decade a change in treatment of acute Achilles tendon rupture away from operative towards non-operative treatment has taken place...

  7. Spontaneous Splenic Rupture in Melanoma

    Directory of Open Access Journals (Sweden)

    Hadi Mirfazaelian


    Full Text Available Spontaneous rupture of spleen due to malignant melanoma is a rare situation, with only a few case reports in the literature. This study reports a previously healthy, 30-year-old man who came with chief complaint of acute abdominal pain to emergency room. On physical examination, abdominal tenderness and guarding were detected to be coincident with hypotension. Ultrasonography revealed mild splenomegaly with moderate free fluid in abdominopelvic cavity. Considering acute abdominal pain and hemodynamic instability, he underwent splenectomy with splenic rupture as the source of bleeding. Histologic examination showed diffuse infiltration by tumor. Immunohistochemical study (positive for S100, HMB45, and vimentin and negative for CK, CD10, CK20, CK7, CD30, LCA, EMA, and chromogranin confirmed metastatic malignant melanoma. On further questioning, there was a past history of a nasal dark skin lesion which was removed two years ago with no pathologic examination. Spontaneous (nontraumatic rupture of spleen is an uncommon situation and it happens very rarely due to neoplastic metastasis. Metastasis of malignant melanoma is one of the rare causes of the spontaneous rupture of spleen.

  8. Spontaneous bilateral quadriceps tendon rupture. (United States)

    Vigneswaran, N; Lee, K; Yegappan, M


    Spontaneous bilateral quadriceps tendon ruptures are uncommon. We present a 30-year-old man with end-stage renal failure, who sustained this injury, and subsequently had surgical repair of both tendons on separate occasions. He has since regained full range of movement of both knees.

  9. Mechanics of Multifault Earthquake Ruptures (United States)

    Fletcher, J. M.; Oskin, M. E.; Teran, O.


    The 2010 El Mayor-Cucapah earthquake of magnitude Mw 7.2 produced the most complex rupture ever documented on the Pacific-North American plate margin, and the network of high- and low-angle faults activated in the event record systematic changes in kinematics with fault orientation. Individual faults have a broad and continuous spectrum of slip sense ranging from endmember dextral strike slip to normal slip, and even faults with thrust sense of dip slip were commonly observed in the aftershock sequence. Patterns of coseismic slip are consistent with three-dimensional constrictional strain and show that integrated transtensional shearing can be accommodated in a single earthquake. Stress inversions of coseismic surface rupture and aftershock focal mechanisms define two coaxial, but permuted stress states. The maximum (σ1) and intermediate (σ2) principal stresses are close in magnitude, but flip orientations due to topography- and density-controlled gradients in lithostatic load along the length of the rupture. Although most large earthquakes throughout the world activate slip on multiple faults, the mechanical conditions of their genesis remain poorly understood. Our work attempts to answer several key questions. 1) Why do complex fault systems exist? They must do something that simple, optimally-oriented fault systems cannot because the two types of faults are commonly located in close proximity. 2) How are faults with diverse orientations and slip senses prepared throughout the interseismic period to fail spontaneously together in a single earthquake? 3) Can a single stress state produce multi-fault failure? 4) Are variations in pore pressure, friction and cohesion required to produce simultaneous rupture? 5) How is the fabric of surface rupture affected by variations in orientation, kinematics, total geologic slip and fault zone architecture?

  10. Magnetic resonance imaging in acute tendon ruptures

    Energy Technology Data Exchange (ETDEWEB)

    Daffner, R.H.; Lupetin, A.R.; Dash, N.; Riemer, B.L.


    The diagnosis of acute tendon ruptures of the extensor mechanism of the knee or the Achilles tendon of the ankle may usually be made by clinical means. Massive soft tissue swelling accompanying these injuries often obscures the findings, however. Magnetic resonance imaging (MRI) can rapidly demonstrate these tendon ruptures. Examples of the use of MRI for quadriceps tendon, and Achilles tendon rupture are presented.

  11. Kinematic Seismic Rupture Parameters from a Doppler Analysis (United States)

    Caldeira, Bento; Bezzeghoud, Mourad; Borges, José F.


    The radiation emitted from extended seismic sources, mainly when the rupture spreads in preferred directions, presents spectral deviations as a function of the observation location. This aspect, unobserved to point sources, and named as directivity, are manifested by an increase in the frequency and amplitude of seismic waves when the rupture occurs in the direction of the seismic station and a decrease in the frequency and amplitude if it occurs in the opposite direction. The model of directivity that supports the method is a Doppler analysis based on a kinematic source model of rupture and wave propagation through a structural medium with spherical symmetry [1]. A unilateral rupture can be viewed as a sequence of shocks produced along certain paths on the fault. According this model, the seismic record at any point on the Earth's surface contains a signature of the rupture process that originated the recorded waveform. Calculating the rupture direction and velocity by a general Doppler equation, - the goal of this work - using a dataset of common time-delays read from waveforms recorded at different distances around the epicenter, requires the normalization of measures to a standard value of slowness. This normalization involves a non-linear inversion that we solve numerically using an iterative least-squares approach. The evaluation of the performance of this technique was done through a set of synthetic and real applications. We present the application of the method at four real case studies, the following earthquakes: Arequipa, Peru (Mw = 8.4, June 23, 2001); Denali, AK, USA (Mw = 7.8; November 3, 2002); Zemmouri-Boumerdes, Algeria (Mw = 6.8, May 21, 2003); and Sumatra, Indonesia (Mw = 9.3, December 26, 2004). The results obtained from the dataset of the four earthquakes agreed, in general, with the values presented by other authors using different methods and data. [1] Caldeira B., Bezzeghoud M, Borges JF, 2009; DIRDOP: a directivity approach to determining

  12. Synthetic modeling of a fluid injection-induced fault rupture with slip-rate dependent friction coefficient (United States)

    Urpi, Luca; Rinaldi, Antonio Pio; Rutqvist, Jonny; Cappa, Frédéric; Spiers, Christopher J.


    Poro-elastic stress and effective stress reduction associated with deep underground fluid injection can potentially trigger shear rupture along pre-existing faults. We modeled an idealized CO2 injection scenario, to assess the effects on faults of the first phase of a generic CO2 aquifer storage operation. We used coupled multiphase fluid flow and geomechanical numerical modeling to evaluate the stress and pressure perturbations induced by fluid injection and the response of a nearby normal fault. Slip-rate dependent friction and inertial effects have been aken into account during rupture. Contact elements have been used to take into account the frictional behavior of the rupture plane. We investigated different scenarios of injection rate to induce rupture on the fault, employing various fault rheologies. Published laboratory data on CO2-saturated intact and crushed rock samples, representative of a potential target aquifer, sealing formation and fault gouge, have been used to define a scenario where different fault rheologies apply at different depths. Nucleation of fault rupture takes place at the bottom of the reservoir, in agreement with analytical poro-elastic stress calculations, considering injection-induced reservoir inflation and the tectonic scenario. For the stress state here considered, the first triggered rupture always produces the largest rupture length and slip magnitude, correlated with the fault rheology. Velocity weakening produces larger ruptures and generates larger magnitude seismic events. Heterogeneous faults have been considered including velocity-weakening or velocity strengthening sections inside and below the aquifer, while upper sections being velocity-neutral. Nucleation of rupture in a velocity strengthening section results in a limited rupture extension, both in terms of maximum slip and rupture length. For a heterogeneous fault with nucleation in a velocity-weakening section, the rupture may propagate into the overlying velocity

  13. Along-strike rupture directivity of earthquakes of the 2009 L'Aquila, central Italy, seismic sequence (United States)

    Calderoni, G.; Rovelli, A.; Ben-Zion, Y.; Di Giovambattista, R.


    We perform a systematic investigation of along-strike rupture directivity of 70 earthquakes (3.0 ≤ Mw ≤ 6.1) of the 2009 L'Aquila seismic sequence by analysing azimuthal variations of broad-band seismograms recorded in the distance range 60 km earthquake quantifies the spectral separation above the corner frequency of the target event at opposite along-strike directions. A large number (73 per cent) of events including the Mw 6.1 main shock show high (>0.7) IDIR values indicating predominantly unilateral rupture propagation. The preferred rupture propagation direction is generally to the southeast with no dependence on the earthquake magnitude or occurrence time. Events on two main faults (L'Aquila and Campotosto) show somewhat different behaviour. Almost all earthquakes on the L'Aquila fault have strong unilateral directivity to the southeast, whereas earthquakes on the Campotosto fault show more diverse behaviour. However, there is a predominance of unilateral ruptures (14 out of 22) also on the Campotosto fault, and the few (five) earthquakes with ruptures to the northwest are limited to the most northwestern segment of the fault. The spectral results are consistent with time-domain analysis when the latter samples adequately the frequency band above corner frequency. The preferred rupture direction may be produced at least in part by a velocity contrast across the fault. The results provide important input for estimates of seismic motion and physics of earthquake ruptures.

  14. Ultrasonography in traumatic rupture of Schilles tendon

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Kil Ho; Byun, Woo Mok; Lee, Dong Chul; Kim, Se Dong; Park, Bok Hwan [Yeungnam University College of Medicine, Gyeongsan (Korea, Republic of)


    Ultrasonography was performed prospectively in 16 patients with suspected rupture of Achilles tendon from March to October 1992 to evaluate the diagnostic value of ultrasonography. Ultrasonography examinations were done according to standard techniques, and then dynamic evaluations were performed during passive plantar flexion of the ankle. We reviewed 10 confirmed cases of ruptured tendons, among which 9 cases were confirmed by operation,and one by ultrasonography and MRI. ultrasonic results were compared with the findings at physical examination and surgery. The normal thickness of the Achilles tendons in healthy sides on ultrasonography ranged from 3 to 5mm.The ruptured tendons were 6-10mm thick at 1-2cm superior to the upper margin of Os Calcis. Rupture sites on ultrasonography were exactly predicted in 7 among the 9 operative cases. In on non-operative case, the rupture site on ultrasonography corresponded to that seen on MRI. Tendon bucking on dynamic ultrasonography was positive in all 4 complete ruptures. In 2 of the 6 partial ruptures which were near complete tears, tendon buckling was also observed. In conclusion, ultrasonography is a valuable diagnostic modality in the diagnosis of Achilles tendon rupture, the differentiation between total and partial rupture, and in determining the rupture site. We consider ultrasonography of tendon as an important diagnostic toot that may guide the treatment plan in the traumatic rupture of the Achilles tendon

  15. The diagnosis of breast implant rupture

    DEFF Research Database (Denmark)

    Hölmich, Lisbet R; Vejborg, Ilse; Conrad, Carsten;


    STUDY OBJECTIVE: The aim of this study was to evaluate the accuracy of Magnetic Resonance Imaging (MRI) as performed according to a strict study protocol in diagnosing rupture of silicone breast implants. MATERIAL AND METHODS: The study population consisted of 64 women with 118 implants, who had...... participated in either one or two study MRI examinations, aiming at determining the prevalence and incidence of silent implant rupture, respectively, and who subsequently underwent explantation. Implant rupture status was determined by four independent readers and a consensus diagnosis of either rupture...... (intracapsular or extracapsular), possible rupture or intact implant was then obtained. Strict predetermined rupture criteria were applied as described in this report and findings at surgery were abstracted in a standardised manner and results compared. RESULTS: At MRI, 66 implants were diagnosed as ruptured...

  16. Rupture process and coseismic deformations of the 27 February 2010 Maule earthquake, Chile (United States)

    Pulido, Nelson; Yagi, Yuji; Kumagai, Hiroyuki; Nishimura, Naoki


    We estimated the spatial and temporal slip distribution for the 27 February 2010 Maule earthquake from teleseismic body wave data. To obtain a stable inversion solution, we used the data covariance matrix from the observation and modeling errors, incorporated smoothing constraints and determined their optimal values by using the Akaike Bayesian Information Criterion (ABIC). The fault rupture can be divided into three stages. For the first 30 s the rupture started as an elliptical crack elongated in the in-plane direction along the dip. After 30 s the rupture propagated bi-laterally along strike reaching the maximum moment release rate at around 50 s near the hypocenter. Finally the rupture propagated mainly to the north reaching another peak of moment release rate at 80 s and 130 km north-east from the hypocenter. Main rupture lasted for about 110 s. In order to evaluate our source model, we calculated the predicted coseismic vertical displacements and compare them with observed uplift/subsidence values measured along the coastline, as well as displacements obtained from strong ground motion and high-sampling GPS records in Concepción. Our model provides good estimations of the static displacements in the northern source region, but under-estimates the coseismic uplifts in the southern region.

  17. Crack front propagation by kink formation

    Energy Technology Data Exchange (ETDEWEB)

    Roesch, Frohmut; Trebin, Hans-Rainer [Universitaet Stuttgart, Institut fuer Theoretische und Angewandte Physik, 70550 Stuttgart (Germany)


    In a brittle material a travelling crack generates an upper and a lower fracture surface, which meet at a one-dimensional crack front. From a macroscopic point of view there is no reason why this curve should deviate from a straight line, contrary to the atomistic point of view, where a crack propagates by successive rupture of cohesive bonds. We investigate fracture of the C15 NbCr{sub 2} Friauf-laves phase on an atomic level by means of molecular dynamics simulations. The numerical experiments highlight that crack fronts in general do not form a straight line and propagate by kink-pair formation at low loads (EPL 87 (2009) 66004). This mechanism should be relevant for crack propagation in any ordered brittle solid.

  18. [Quadriceps and patellar tendon ruptures]. (United States)

    Grim, C; Lorbach, O; Engelhardt, M


    Ruptures of the quadriceps or patellar tendon are uncommon but extremely relevant injuries. Early diagnosis and surgical treatment with a stable suture construction are mandatory for a good postoperative clinical outcome. The standard methods of repair for quadriceps and patellar tendon injuries include the placement of suture loops through transpatellar tunnels. Reinforcement with either a wire cerclage or a PDS cord is used in patellar tendon repair. The PDS cord can also be applied as augmentation in quadriceps tendon repair. In secondary patellar tendon repair an autologous semitendinosus graft can be used. For chronic quadriceps tendon defects a V-shaped tendon flap with a distal footing is recommended. The different methods of repair should lead to early functional postoperative treatment. The clinical outcome after surgical treatment of patellar and quadriceps tendon ruptures is mainly good.

  19. Bubble rupture in bubble electrospinning

    Directory of Open Access Journals (Sweden)

    Chen Rouxi


    Full Text Available As the distinctive properties and different applications of nanofibers, the demand of nanofibers increased sharply in recently years. Bubble electrospinning is one of the most effective and industrialized methods for nanofiber production. To optimize the set-up of bubble electrospinning and improve its mass production, the dynamic properties of un-charged and charged bubbles are studied experimentally, the growth and rupture process of a bubble are also discussed in this paper.

  20. Molecular dynamics of interface rupture (United States)

    Koplik, Joel; Banavar, Jayanth R.


    Several situations have been studied in which a fluid-vapor or fluid-fluid interface ruptures, using molecular dynamics simulations of 3000 to 20,000 Lennard-Jones molecules in three dimensions. The cases studied are the Rayleigh instability of a liquid thread, the burst of a liquid drop immersed in a second liquid undergoing shear, and the rupture of a liquid sheet in an extensional flow. The late stages of the rupture process involve the gradual withdrawal of molecules from a thinning neck, or the appearance and growth of holes in a sheet. In all cases, it is found that despite the small size of the systems studied, tens of angstroms, the dynamics is in at least qualitative accord with the behavior expected from continuum calculations, and in some cases the agreement is to within tens of percent. Remarkably, this agreement occurs even though the Eulerian velocity and stress fields are essentially unmeasurable - dominated by thermal noise. The limitations and prospects for such molecular simulation techniques are assessed.

  1. Quadriceps tendon rupture - treatment results

    Directory of Open Access Journals (Sweden)

    Popov Iva


    Full Text Available Introduction. Quadriceps tendon rupture is a rare but rather serious injury. If this injury is not promptly recognized and early operated, it may lead to disability. This research was aimed at pointing out the results and complications of the quadriceps tendon rupture surgical treatment. Material and Methods. This retrospective multicentric study was conducted in a group of 29 patients (mostly elderly men. Lysholm knee scoring scale was used to evaluate the surgical results. The post-operative results were compared in relation to the type of tendon rupture reconstructions (acute or chronic, various surgical techniques, type of injuries (unilateral or bilateral as well as the presence or absence of comorbid risk factors in the patients. Results. The average value of a Lysholm score was 87.6. Excellent and satisfactory Lysholm score results dominated in our sample of patients. Better post-operative results were recorded in the group of patients without risk factors, in case of a bilateral injury, and in case of an acute injury. The best result was obtained after performing the reconstruction using anchors, and the worst result came after using Codivilla technique. Discussion and Conclusion. Early diagnosis and surgical treatment are an absolute imperative in management of this injury. We have not proven that a certain surgical technique has an advantage over the others. A comorbid risk factor is related to a lower Lysholm score. Despite a few cases of complications, we can conclude that the surgical treatment yields satisfactory results.

  2. Splenic rupture following routine colonoscopy. (United States)

    Rasul, Tabraze; Leung, Edmund; McArdle, Kirsten; Pathak, Rajiv; Dalmia, Sanjay


    Splenic rupture is a life-threatening condition characterized by internal hemorrhage, often difficult to diagnose. Colonoscopy is a gold standard routine diagnostic test to investigate patients with gastrointestinal symptoms as well as to those on the screening program for colorectal cancer. Splenic injury is seldomly discussed during consent for colonoscopy, as opposed to colonic perforation, as its prevalence accounts for less than 0.1%. A 66-year-old Caucasian woman with no history of collagen disorder was electively admitted for routine colonoscopy for surveillance of adenoma. She was admitted following the procedure for re-dosing of warfarin, which was stopped prior to the colonoscopy. The patient was found collapsed on the ward the following day with clinical shock and anemia. Computed tomography demonstrated grade 4 splenic rupture. Immediate blood transfusion and splenectomy was required. Splenic rupture following routine colonoscopy is extremely rare. Awareness of it on this occasion saved the patient's life. Despite it being a rare association, the seriousness warrants inclusion in all information leaflets concerning colonoscopy and during its consent.

  3. Molecular dynamics of interface rupture (United States)

    Koplik, Joel; Banavar, Jayanth R.


    Several situations have been studied in which a fluid-vapor or fluid-fluid interface ruptures, using molecular dynamics simulations of 3000 to 20,000 Lennard-Jones molecules in three dimensions. The cases studied are the Rayleigh instability of a liquid thread, the burst of a liquid drop immersed in a second liquid undergoing shear, and the rupture of a liquid sheet in an extensional flow. The late stages of the rupture process involve the gradual withdrawal of molecules from a thinning neck, or the appearance and growth of holes in a sheet. In all cases, it is found that despite the small size of the systems studied, tens of angstroms, the dynamics is in at least qualitative accord with the behavior expected from continuum calculations, and in some cases the agreement is to within tens of percent. Remarkably, this agreement occurs even though the Eulerian velocity and stress fields are essentially unmeasurable - dominated by thermal noise. The limitations and prospects for such molecular simulation techniques are assessed.

  4. Spatiotemporal properties of Sub-Rayleigh and supershear rupture velocity fields: Theory and experiments (United States)

    Mello, Michael; Bhat, Harsha S.; Rosakis, Ares J.


    Fundamental spatiotemporal field properties and particle velocity waveform signatures of sub-Rayleigh and supershear ruptures were experimentally investigated through a series of laboratory earthquake experiments. We appeal to dynamic rupture theory to extract and highlight previously unnoticed aspects and results, which are of direct relevance to our new experiments. Kinematic relationships derived from both singular and non-singular solutions are applied to analyze and interpret various features observed in these experiments. A strong correspondence is demonstrated between particle velocity records obtained in lab experiments and synthetic particle velocity waveform profiles derived from theory. Predicted temporal profiles, sense of particle motion, and amplitude decay properties of sub-Rayleigh and supershear particle velocity waveforms are experimentally verified. In a particular set of supershear rupture experiments, the fault-normal (FN) and fault-parallel (FP) velocity waveforms were simultaneously recorded at fixed, off-fault field points as a shear Mach front swept these locations. Particle velocity records collected over a broad range of stable supershear rupture speeds validate the predicted scaling relationship δu˙1s / δu˙2s =√{Vr2 / Cs2-1 } =βs, between the FP (δu1ṡ) and the FN (δu2ṡ) velocity jumps propagated by a shear Mach front. Additional experimental findings include detailed rupture speed measurements of sub-Rayleigh and supershear ruptures and the observation of a supershear daughter crack with vanishing shear Mach front.

  5. Large scale dynamic rupture scenario of the 2004 Sumatra-Andaman megathrust earthquake (United States)

    Ulrich, Thomas; Madden, Elizabeth H.; Wollherr, Stephanie; Gabriel, Alice A.


    The Great Sumatra-Andaman earthquake of 26 December 2004 is one of the strongest and most devastating earthquakes in recent history. Most of the damage and the ~230,000 fatalities were caused by the tsunami generated by the Mw 9.1-9.3 event. Various finite-source models of the earthquake have been proposed, but poor near-field observational coverage has led to distinct differences in source characterization. Even the fault dip angle and depth extent are subject to debate. We present a physically realistic dynamic rupture scenario of the earthquake using state-of-the-art numerical methods and seismotectonic data. Due to the lack of near-field observations, our setup is constrained by the overall characteristics of the rupture, including the magnitude, propagation speed, and extent along strike. In addition, we incorporate the detailed geometry of the subducting fault using Slab1.0 to the south and aftershock locations to the north, combined with high-resolution topography and bathymetry data.The possibility of inhomogeneous background stress, resulting from the curved shape of the slab along strike and the large fault dimensions, is discussed. The possible activation of thrust faults splaying off the megathrust in the vicinity of the hypocenter is also investigated. Dynamic simulation of this 1300 to 1500 km rupture is a computational and geophysical challenge. In addition to capturing the large-scale rupture, the simulation must resolve the process zone at the rupture tip, whose characteristic length is comparable to smaller earthquakes and which shrinks with propagation distance. Thus, the fault must be finely discretised. Moreover, previously published inversions agree on a rupture duration of ~8 to 10 minutes, suggesting an overall slow rupture speed. Hence, both long temporal scales and large spatial dimensions must be captured. We use SeisSol, a software package based on an ADER-DG scheme solving the spontaneous dynamic earthquake rupture problem with high

  6. Tunnel effect of fractal fault and transient S-wave velocity rupture (TSVR) of in-plane shear fault

    Institute of Scientific and Technical Information of China (English)


    Transient S-wave velocity rupture (TSVR) means the velocity of fault rupture propagation is between S-wave velocity βand P-wave velocity α. Its existing in the rupture of in-plane (i.e. strike-slip) fault has been proved, but in 2-dimensional classical model, there are two difficulties in transient S-wave velocity rupture, i.e., initialization difficulty and divergence difficulty in interpreting the realization of TSVR. The initialization difficulty means, when v↑vR (Rayleigh wave velocity), the dynamic stress strength factor K2(t)→+0, and changes from positive into negative in the interval (vR,β). How v transit the forbidden of (vR,β)? The divergence difficulty means K2(t)→+ when v↓. Here we introduce the concept of fractal and tunnel effect that exist everywhere in fault. The structure of all the faults is fractal with multiple cracks. The velocity of fault rupture is differentiate of the length of the fault respect to time, so the rupture velocity is also fractal. The tunnel effect means the dynamic rupture crosses over the interval of the cracks, and the coalescence of the intervals is slower than the propagation of disturbance. Suppose the area of earthquake nucleation is critical or sub-critical propagation everywhere, the arriving of disturbance triggers or accelerates the propagation of cracks tip at once, and the observation system cannot distinguish the front of disturbance and the tip of fracture. Then the speed of disturbance may be identified as fracture velocity, and the phenomenon of TSVR appears, which is an apparent velocity. The real reason of apparent velocity is that the mathematics model of shear rupture is simplified of complex process originally. The dual character of rupture velocity means that the apparent velocity of fault and the real velocity of micro-crack extending, which are different in physics, but are unified in rupture criterion. Introducing the above-mentioned concept to the calculation of K2 (t), the difficulty of

  7. Spatial and temporal rupture process of the January 26, 2001, Gujarat, India, MS=7.8 earthquake

    Institute of Scientific and Technical Information of China (English)

    许力生; 陈运秦; 高孟潭


    The source parameters, such as moment tensor, focal mechanism, source time function (STF) and temporal-spatial rupture process, were obtained for the January 26, 2001, India, MS=7.8 earthquake by inverting waveform data of 27 GDSN stations with epicentral distances less than 90o. Firstly, combining the moment tensor inversion, the spatial distribution of intensity, disaster and aftershocks and the orientation of the fault where the earthquake lies, the strike, dip and rake of the seismogenic fault were determined to be 92o, 58o and 62o, respectively. That is, this earthquake was a mainly thrust faulting with the strike of near west-east and the dipping direction to south. The seismic moment released was 3.5(1020 Nm, accordingly, the moment magnitude MW was calculated to be 7.6. And then, 27 P-STFs, 22 S-STFs and the averaged STFs of them were determined respectively using the technique of spectra division in frequency domain and the synthetic seismogram as Green(s functions. The analysis of the STFs suggested that the earthquake was a continuous event with the duration time of 19 s, starting rapidly and ending slowly. Finally, the temporal-spatial distribution of the slip on the fault plane was imaged from the obtained P-STFs and S-STFs using an time domain inversion technique. The maximum slip amplitude on the fault plane was about 7 m. The maximum stress drop was 30 MPa, and the average one over the whole rupture area was 7 MPa. The rupture area was about 85 km long in the strike direction and about 60 km wide in the down-dip direction, which, equally, was 51 km deep in the depth direction. The rupture propagated 50 km eastwards and 35 km westwards. The main portion of the rupture area, which has the slip amplitude greater than 0.5 m, was of the shape of an ellipse, its major axis oriented in the slip direction of the fault, which indicated that the rupture propagation direction was in accordance with the fault slip direction. This phenomenon is popular for

  8. Ruptures along a frictional interface are described by Fracture Mechanics: Experiments in a "Laboratory Earthquake" along both dry and lubricated interfaces (United States)

    Fineberg, J.; Svetlizky, I.; Bayart Schweizer, E.


    A dry frictional interface is composed of an ensemble of discrete contacts whose real contact area is orders of magnitude smaller than the nominal one. Slip is initiated when contacts are broken via propagating ruptures. Characterization of the dynamic fields that drive these ruptures and how they couple to the dissipative mechanisms on the interface are critical to our fundamental understanding of both frictional motion and earthquake dynamics. We experimentally investigate ruptures along rough spatially extended interfaces bounded by the same type of material. We perform simultaneous high-speed measurements (at μsec time scale) of the real contact area and the strain fields in the region surrounding propagating rupture tips. These measurements enable us to uncover the breakdown process near the tip of the slipping zone for rapidly propagating ruptures ranging from slow rupture fronts (~0.01CR) to nearly the Rayleigh wave speed, CR~1255m/s. These rupture fronts are quantitatively described by classical singular solutions for rapid shear cracks. These singular solutions, originally derived to describe brittle fracture, are in excellent agreement with the experiments for slow propagation, whereas some significant discrepancies arise as the rupture velocity approaches CR. The energy dissipated by the fracture of the contacts (fracture energy) is nearly constant throughout the entire rupture velocity range, while the size of the dissipative zone undergoes a 'Lorentz-like' contraction as the rupture velocity approaches CR. We then turn to both fully lubricated and partially lubricated interfaces and compare the dynamic strain fields measured to those of dry interfaces. The results of these studies are surprising. We will show that: Rapid rupture fronts still propagate in the stick-slip regime Although decreasing the overall friction coefficient along the interface, the addition of a lubricant significantly increases the fracture energy at the rupture tip In the fully

  9. Histologic analysis of ruptured quadriceps tendons. (United States)

    Trobisch, Per David; Bauman, Matthias; Weise, Kuno; Stuby, Fabian; Hak, David J


    Quadriceps tendon ruptures are uncommon injuries. Degenerative changes in the tendon are felt to be an important precondition for rupture. We retrospectively reviewed 45 quadriceps tendon ruptures in 42 patients. Quadriceps tendon ruptures occurred most often in the sixth and seventh decade of life. Men were affected six times as often as women. A tissue sample from the rupture-zone was obtained in 22 cases and histologic analysis was performed. Degenerative changes were present in only 14 (64%) of the 22 samples. We observed an increasing ratio of degenerative to nondegenerative tendons with increasing patient age. Our data suggests that quadriceps tendon rupture, especially in younger patients, can occur in the absence of pathologic tendon degeneration.

  10. Treatment of bronchial ruptures by delayed surgery

    Institute of Scientific and Technical Information of China (English)


    Objective:To study the causes that resulted in delayed surgery for bronchial ruptures and the results.Methods:The cases with the bronchial ruptures by the delayed surgery last decade were retrospectively reviewed.The causes and unsatisfactory results were analysed.Results:The severe complications usually occurred after the delayed surgery and the results were not as satisfactory as those by early surgery.Conclusion:The bronchial ruptures ought to be operated in the early stage after being wounded.

  11. Achilles tendon rupture; assessment of nonoperative treatment

    DEFF Research Database (Denmark)

    Barfod, Kristoffer Weisskirchner


    BACKGROUND: Acute Achilles tendon rupture is a frequent and potentially disabling injury. Over the past decade a change in treatment of acute Achilles tendon rupture away from operative towards non-operative treatment has taken place. However, the optimal non-operative treatment protocol remains...... and Sweden. Immediate weight-bearing was found to be safe and recommendable in non-operative treatment of acute Achilles tendon rupture. The novel ultrasound measurement showed excellent reliability and acceptable validity and agreement....

  12. Achilles tendon rupture; assessment of nonoperative treatment

    DEFF Research Database (Denmark)

    Barfod, Kristoffer Weisskirchner; Troelsen, Anders


    BACKGROUND: Acute Achilles tendon rupture is a frequent and potentially disabling injury. Over the past decade a change in treatment ofacute Achilles tendon rupture away from operative towards non-operative treatment has taken place. However, the optimal non-operative treatment protocol remains...... and Sweden. Immediate weight-bearing was found to be safe and recommendable in non-operative treatment of acute Achilles tendon rupture. The novel ultrasound measurement showed excellent reliability and acceptable validity and agreement....

  13. Pathological rupture of malarial spleen.

    Directory of Open Access Journals (Sweden)

    Mokashi A


    Full Text Available Two cases of spontaneous rupture of malarial spleen are reported here. One of them was a male who was on chloroquine for an acute attack of malaria. While on therapy, he complained of pain in left hypochondrium followed by palpitations. The other patient was a female who was admitted for continuous dull aching pain and fever. In both the patients, exploratory laparotomy revealed an enlarged spleen with tear. Splenectomy was performed. Histopathological examination revealed dilated congested sinusoid with follicular atrophy, and RBCs with malarial parasites. The post-operative course was smooth in both patients.

  14. Ruptured jejunum following Heimlich maneuver. (United States)

    Razaboni, R M; Brathwaite, C E; Dwyer, W A


    The Heimlich maneuver, over time, has proved to be a useful resuscitative procedure in the management of cases with airway occlusion secondary to foreign body. Medical treatments, however, can have side effects, and this maneuver is no exception. A previously unreported complication is presented, that of jejunal rupture. The proper application of the maneuver minimizes the number of side effects; however, since they do occur, it is suggested that all persons subject to this maneuver be subsequently evaluated by a physician as soon after the incident as is practicable.

  15. The rupture in visual language:


    Kula, Ömür; Kula, Omur


    The shift of arts from conventional forms of canvas-painting and sculpture to collage, ready-mades, installations and performances as it had occurred in the history of western art follow a linear and natural unfolding in parallel with sociopolitical evolvements. In the case of Turkish visual arts, this kind of a transformation projects to the time period between 1960s to 1990s where the face of arts change not smoothly but rather in the form of a 'rupture' as new tendencies are embraced, prac...

  16. Mechanical model of vulnerable atherosclerotic plaque rupture

    Institute of Scientific and Technical Information of China (English)

    SU; Haijun; ZHANG; Mei; ZHANG; Yun


    Rupture of atherosclerotic plaque is the main trigger of acute cardiovascular events, but the mechanism of plaque rupture is still unknown. We have constructed a model describing the motion of the fibrous cap of the plaque using the theory of elastic mechanics and studied the stability of the plaque theoretically. It has shown that plaque rupture is the result of a dynamic interplay between factors intrinsic to the plaque itself and extrinsic factors. We have proposed a new mechanism of plaque rupture, given a new explanation about the nonlinear dynamic progress of atherosclerosis and suggested a method to identify the vulnerable plaques to manage atherosclerosis.

  17. Delayed presentation of traumatic intraperitoneal bladder rupture

    Energy Technology Data Exchange (ETDEWEB)

    Brown, D.; Magill, H.L.; Black, T.L.


    A child with urine ascites as a delayed manifestation of post-traumatic intraperitoneal bladder rupture is presented. The diagnosis was suggested by abdominal CT scan and confirmed with a cystogram. While uncommon, late presentation of intraperitoneal bladder rupture following trauma may occur from masking of a primary laceration or development of secondary rupture at the site of a hematoma in the bladder wall. Since CT may be a primary diagnostic study performed following abdominal trauma, the radiologist should be aware of CT findings suggesting bladder rupture and of the possibility of delayed presentation of this injury.

  18. Stress rupture properties of GH4169 superalloy

    Directory of Open Access Journals (Sweden)

    Xudong Lu


    Full Text Available GH4169 alloy is a nickel-based superalloy extensively used in the aircraft engine industry because of its excellent mechanical properties and good fabrication ability. The mechanical properties of the GH4169 at high temperature, rupture stress under severe condition deserves a close attention. In this paper, the creep rupture of the GH4169 alloy under constant load and different temperatures from 550 °C to 700 °C conditions is systematically evaluated and major impact factors in the stress rupture behavior are analyzed. Furthermore, an improving method for the alloy stress rupture is proposed.

  19. Dynamic Source Rupture Process of the 2016 Kumamoto, Japan, earthquake (United States)

    Yu, Xiangwei; Zhang, Wenbo


    obtained dynamic source model. Our result shows that in general large stress drop occurred around areas with a large slip except the shallow part around the hypocenter. Although kinematic source model shows that this area has a large slip, the stress drop is not so large comparing with the deep areas that has a similar amount of slip. The estimated strength excess is generally small and that suggests the tectonic shear stress has reached near the level of the fault strength before the main shock. Usually, the area with a large strength excess on the fault surface will delay the rupture propagation. Thus, the rupture propagation becomes slow down at these areas. Faster rupture is observed at the main asperity area whereas slower rupture at the northwestern deep part is shown in the dynamic source model. Based on the dynamic source model, near-source ground motions are simulated. Generally, the synthetic waveforms show well the observed record characteristics. This shows that our dynamic source model reproduces the main features of the long period ground motions in this earthquake.

  20. Deep vein thrombosis and pulmonary embolus associated with a ruptured popliteal aneurysm – a cautionary note

    Directory of Open Access Journals (Sweden)

    Lewis Mike H


    Full Text Available Abstract Popliteal artery aneurysms representing 80% of peripheral artery aneurysms rarely rupture (a reported incidence of 0.1–2.8 % and second commonest in frequency after aorto-iliac aneurysms. They usually present with pain, swelling, occlusion or distal embolisation and can cause diagnostic difficulties. We report a 78 year old man who was previously admitted to hospital with a pulmonary embolus secondary to deep venous thrombosis. He was heparinized then warfarinised and was readmitted with a ruptured popliteal aneurysm leading to a large pseudo aneurysm formation. The pulmonary embolus had been due to popliteal vein thrombosis and propagation of the clot. A thorough review of literature identified only one previously reported case of ruptured popliteal artery aneurysm and subsequent large pseudo aneurysm formation. We feel it is important to exclude a popliteal aneurysm in a patient with DVT. This may be more common than the published literature suggests.

  1. Influence des inclusions sur la rupture d'un acier faiblement allié (United States)

    Hausild, P.; Berdin, C.; Bompard, P.; Prioul, C.


    L'étude de la rupture d'un acier faiblement allié dans le domaine de la transition ductile fragile a permis de mettre en évidence la présence croissante, avec la température de sollicitation, d'amas d'inclusions de seconde phase sur les surfaces de rupture. On montre, à l'aide de modélisations par éléments finis, que ces amas jouent néanmoins un rôle mineur dans le déclenchement du clivage. En revanche, leur influence sur la propagation de la rupture ductile est importante. On peut alors expliquer l'anisotropie de la résilience en prenant en compte la géométrie des inclusions et leur répartition spatiale.

  2. Coseismic rupturing stopped by Aso volcano during the 2016 Mw 7.1 Kumamoto earthquake, Japan. (United States)

    Lin, A; Satsukawa, T; Wang, M; Mohammadi Asl, Z; Fueta, R; Nakajima, F


    Field investigations and seismic data show that the 16 April 2016 moment magnitude (Mw) 7.1 Kumamoto earthquake produced a ~40-kilometer-long surface rupture zone along the northeast-southwest-striking Hinagu-Futagawa strike-slip fault zone and newly identified faults on the western side of Aso caldera, Kyushu Island, Japan. The coseismic surface ruptures cut Aso caldera, including two volcanic cones inside it, but terminate therein. The data show that northeastward propagation of coseismic rupturing terminated in Aso caldera because of the presence of magma beneath the Aso volcanic cluster. The seismogenic faults of the 2016 Kumamoto earthquake may require reassessment of the volcanic hazard in the vicinity of Aso volcano.

  3. Coseismic rupturing stopped by Aso volcano during the 2016 Mw 7.1 Kumamoto earthquake, Japan (United States)

    Lin, A.; Satsukawa, T.; Wang, M.; Mohammadi Asl, Z.; Fueta, R.; Nakajima, F.


    Field investigations and seismic data show that the 16 April 2016 moment magnitude (Mw) 7.1 Kumamoto earthquake produced a ~40-kilometer-long surface rupture zone along the northeast-southwest-striking Hinagu-Futagawa strike-slip fault zone and newly identified faults on the western side of Aso caldera, Kyushu Island, Japan. The coseismic surface ruptures cut Aso caldera, including two volcanic cones inside it, but terminate therein. The data show that northeastward propagation of coseismic rupturing terminated in Aso caldera because of the presence of magma beneath the Aso volcanic cluster. The seismogenic faults of the 2016 Kumamoto earthquake may require reassessment of the volcanic hazard in the vicinity of Aso volcano.

  4. Quadriceps and patellar tendon ruptures. (United States)

    Lee, Dennis; Stinner, Daniel; Mir, Hassan


    The diagnosis of quadriceps and patellar tendon ruptures requires a high index of suspicion and thorough history-taking to assess for medical comorbidities that may predispose patients to tendon degeneration. Radiographic assessment with plain films supplemented by ultrasound and magnetic resonance imaging when the work-up is equivocal further aids diagnosis; however, advanced imaging is often unnecessary in patients with functional extensor mechanism deficits. Acute repair is preferred, and transpatellar bone tunnels serve as the primary form of fixation when the tendon rupture occurs at the patellar insertion, with or without augmentation depending on surgeon preference. Chronic tears and disruptions following total knee arthroplasty are special cases requiring reconstructions with allograft, synthetic mesh, or autograft. Rehabilitation protocols generally allow immediate weight-bearing with the knee locked in extension and crutch support. Limited arc motion is started early with active flexion and passive extension and then advanced progressively, followed by full active range of motion and strengthening. Complications are few but include quadriceps atrophy, knee stiffness, and rerupture. Outcomes are excellent if repair is done acutely, with poorer outcomes associated with delayed repair.

  5. Rupture directivity of micro-earthquakes along the San Andreas fault (United States)

    Wang, E.; Rubin, A. M.


    Theoretically, it is expected that earthquakes occurring on an interface separating materials with different elastic properties might have a preferential rupture propagation direction. To test for this, we searched for indications of directivity by examining spectral ratios of multiple pairs of nearby earthquakes at azimuthally distributed seismic stations. By taking the spectral ratios, this technique is capable of canceling path and station terms in seismic spectra. It differs from a typical empirical Green's Function approach in that it compares events with similar sizes as well as events with significant size differences. The spectral ratios are fitted with a simple forward model, in which a bidirectional earthquake source is composed of two point sources moving at constant velocities in opposite directions (assumed to be horizontal). Each bidirectional earthquake has four model parameters: the lengths of the two rupture halves running in opposite directions, and their propagation velocities. A priori information concerning the total rupture length of bidirectional events are computed from catalog magnitude using a moment-magnitude relation and a 3MPa stress drop on an equidimensional rupture. The a priori rupture velocity is peaked at 0.8Vs and constrained to be smaller than Vs. Since identical earthquakes would produce frequency-independent spectral ratios at all azimuths, determining the initiation points of earthquakes requires variability in event size and/or relative directivity. The relocated catalog of Rubin [2002] was used to define 78 clusters of repeating earthquakes along the central San Andreas fault. The spectral ratios of all combinations of earthquake pairs in each cluster were fitted with synthetic spectral ratios at stations with sufficient signal-to-noise ratio and coherence. The inversion results show that, as might have been expected, differences in rupture processes (duration and relative directivity) of the earthquakes within most

  6. On the initiation of sustained slip-weakening ruptures by localized stresses

    KAUST Repository

    Galis, Martin


    Numerical simulations of dynamic earthquake rupture require an artificial initiation procedure, if they are not integrated in long-term earthquake cycle simulations. A widely applied procedure involves an \\'overstressed asperity\\', a localized region stressed beyond the static frictional strength. The physical properties of the asperity (size, shape and overstress) may significantly impact rupture propagation. In particular, to induce a sustained rupture the asperity size needs to exceed a critical value. Although criteria for estimating the critical nucleation size under linear slip-weakening friction have been proposed for 2-D and 3-D problems based on simplifying assumptions, they do not provide general rules for designing 3-D numerical simulations. We conduct a parametric study to estimate parameters of the asperity that minimize numerical artefacts (e.g. changes of rupture shape and speed, artificial supershear transition, higher slip-rate amplitudes). We examine the critical size of square, circular and elliptical asperities as a function of asperity overstress and background (off-asperity) stress. For a given overstress, we find that asperity area controls rupture initiation while asperity shape is of lesser importance. The critical area obtained from our numerical results contrasts with published theoretical estimates when background stress is low. Therefore, we derive two new theoretical estimates of the critical size under low background stress while also accounting for overstress. Our numerical results suggest that setting the asperity overstress and area close to their critical values eliminates strong numerical artefacts even when the overstress is large. We also find that properly chosen asperity size or overstress may significantly shorten the duration of the initiation. Overall, our results provide guidelines for determining the size of the asperity and overstress to minimize the effects of the forced initiation on the subsequent spontaneous

  7. Effect of a Material Contrast on a Dynamic Rupture: 3-D (United States)

    Harris, R. A.; Day, S. M.


    We use numerical simulations of spontaneously propagating ruptures to examine the effect of a material contrast on earthquake dynamics. We specifically study the case of a lateral contrast whereby the fault is the boundary between two different rock-types. This scenario was previously studied in two-dimensions by Harris and Day [BSSA, 1997], and Andrews and Ben-Zion [JGR, 1997], in addition to subsequent 2-D studies, but it has not been known if the two-dimensional results are applicable to the real three-dimensional world. The addition of the third dimension implies a transition from pure mode II (i.e., plane-strain) to mixed-mode crack dynamics, which is more complicated since in mode II the shear and normal stresses are coupled whereas in mode III (i.e., anti-plane strain) they are not coupled. We use a slip-weakening fracture criterion and examine the effect on an earthquake rupture of material contrasts of up to 50 percent across the fault zone. We find a surprisingly good agreement between our earlier 2-D results, and our 3-D results for along-strike propagation. We find that the analytical solution presented in Harris and Day [BSSA, 1997] does an excellent job at predicting the bilateral, along-strike rupture velocities for the three-dimensional situation. In contrast, the along-dip propagation behaves much as expected for a purely mode-III rupture, with the rupture velocities up-dip and down-dip showing the expected symmetries.

  8. Size dependent rupture growth at the scale of real earthquake (United States)

    Colombelli, Simona; Festa, Gaetano; Zollo, Aldo


    When an earthquake starts, the rupture process may evolve in a variety of ways, resulting in the occurrence of different magnitude earthquakes, with variable areal extent and slip, and this may produce an unpredictable damage distribution around the fault zone. The cause of the observed diversity of the rupture process evolution is unknown. There are studies supporting the idea that all earthquakes arise in the same way, while the mechanical conditions of the fault zone may determine the propagation and generation of small or large earthquakes. Other studies show that small and large earthquakes are different from the initial stage of the rupture beginning. Among them, Colombelli et al. (2014) observed that the initial slope of the P-wave peak displacement could be a discriminant for the final earthquake size, so that small and large ruptures show a different behavior in their initial stage. In this work we perform a detailed analysis of the time evolution of the P-wave peak amplitude for a set of few, co-located events, during the 2008, Iwate-Miyagi (Japan) earthquake sequence. The events have magnitude between 3.2 and 7.2 and their epicentral coordinates vary in a narrow range, with a maximum distance among the epicenters of about 15 km. After applying a refined technique for data processing, we measured the initial Peak Displacement (Pd) as the absolute value of the vertical component of displacement records, starting from the P-wave arrival time and progressively expanding the time window. For each event, we corrected the observed Pd values at different stations for the distance effect and computed the average logarithm of Pd as a function of time. The overall shape of the Pd curves (in log-lin scale) is consistent with what has been previously observed for a larger dataset by Colombelli et al. (2014). The initial amplitude begins with small values and then increases with time, until a plateau level is reached. However, we observed essential differences in the

  9. Combining Seismic Arrays to Image Detailed Rupture Properties of Large Earthquakes: Evidence for Frequent Triggering of Multiple Faults (United States)

    Ishii, M.; Kiser, E.


    Imaging detailed rupture characteristics using the back-projection method, which time-reverses waveforms to their source, has become feasible in recent years due to the availability of data from large aperture arrays with dense station coverage. In contrast to conventional techniques, this method can quickly and indiscriminately provide the spatio-temporal details of rupture propagation. Though many studies have utilized the back-projection method with a single regional array, the limited azimuthal coverage often leads to skewed resolution. In this study, we enhance the imaging power by combining data from two arrays, i.e., the Transportable Array (TA) in the United States and the High Sensitivity Seismographic Network (Hi-net) in Japan. This approach suppresses artifacts and achieves good lateral resolution by improving distance and azimuthal coverage while maintaining waveform coherence. We investigate four large events using this method: the August 15, 2007 Pisco, Peru earthquake, the September 12, 2007 Southern Sumatra earthquake, the September 29, 2009 Samoa Islands earthquake, and the February 27, 2010 Maule, Chile earthquake. In every case, except the Samoa Islands event, the distance of one of the arrays from the epicenter requires us to use the direct P wave and core phases in the back-projection. One of the common features of the rupture characteristics obtained from the back-projection analysis is spatio-temporal rupture discontinuities, or discrete subevents. Both the size of the gaps and the timing between subevents suggest that multiple segments are involved during giant earthquakes, and that they trigger slip on other faults. For example, the 2009 Samoa Islands event began with a rupture propagating north for about 15 seconds followed by a much larger rupture that originated 30 km northwest of the terminus of the first event and propagated back toward the southeast. The involvement of multiple rupture segments with different slip characteristics

  10. Fault geometry, rupture dynamics and ground motion from potential earthquakes on the North Anatolian Fault under the Sea of Marmara

    KAUST Repository

    Oglesby, David D.


    Using the 3-D finite-element method, we develop dynamic spontaneous rupture models of earthquakes on the North Anatolian Fault system in the Sea of Marmara, Turkey, considering the geometrical complexity of the fault system in this region. We find that the earthquake size, rupture propagation pattern and ground motion all strongly depend on the interplay between the initial (static) regional pre-stress field and the dynamic stress field radiated by the propagating rupture. By testing several nucleation locations, we observe that those far from an oblique normal fault stepover segment (near Istanbul) lead to large through-going rupture on the entire fault system, whereas nucleation locations closer to the stepover segment tend to produce ruptures that die out in the stepover. However, this pattern can change drastically with only a 10° rotation of the regional stress field. Our simulations also reveal that while dynamic unclamping near fault bends can produce a new mode of supershear rupture propagation, this unclamping has a much smaller effect on the speed of the peak in slip velocity along the fault. Finally, we find that the complex fault geometry leads to a very complex and asymmetric pattern of near-fault ground motion, including greatly amplified ground motion on the insides of fault bends. The ground-motion pattern can change significantly with different hypocentres, even beyond the typical effects of directivity. The results of this study may have implications for seismic hazard in this region, for the dynamics and ground motion of geometrically complex faults, and for the interpretation of kinematic inverse rupture models.

  11. Tracheal rupture post-emergency intubation


    Andrea Billè; Luca Errico; Francesco Ardissone; Luciano Cardinale


    Tracheal rupture is an uncommon and potentially lifethreatening complication of endotracheal intubation. We present a case of intrathoracic tracheal rupture in a female patient who required emergent endotracheal intubation for acute respiratory distress related to chronic obstructive pulmonary disease exacerbation. Possible contributing factors to tracheal injury included overinflation of the tube cuff, chronic obstructive pulmonary disease, and chronic steroid use. The patient underwent surg...

  12. Spontaneous rupture of choledochal cyst: case report

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ho Seob; Nam, Kyung Jin; Lee, Jin Hwa; Kim, Chan Sung; Choi, Jong Cheol; Oh, Jong Young [Dong-a University College of Medicine, Pusan (Korea, Republic of)


    Spontaneous rupture of a choledochal cyst leading to biliary peritonitis is a rare complication which can be fatal if not promptly diagnosed. The authors report the ultrasound and CT findings of two cases of spontaneous choledochal cystic rupture and the biliary peritonitis which ensued.

  13. Ruptured liver abscess in a neonate

    Directory of Open Access Journals (Sweden)

    Prashant Jain


    Full Text Available We report a rare case of 17-day-old neonate, diagnosed to have ruptured liver abscess secondary to Methicillin-resistant Staphylococcal aureus infection. The child presented with septicemia and abdominal distension. On exploration, there was pyoperitoneum with ruptured liver abscess.

  14. Simultaneous and spontaneous bilateral quadriceps tendons rupture. (United States)

    Celik, Evrim Coşkun; Ozbaydar, Mehmet; Ofluoglu, Demet; Demircay, Emre


    Simultaneous and spontaneous bilateral quadriceps tendon rupture is an uncommon injury that is usually seen in association with multiple medical conditions and some medications. We report a case of simultaneous and spontaneous bilateral quadriceps tendon rupture that may be related to the long-term use of a statin.

  15. Migraine before rupture of intracranial aneurysms

    DEFF Research Database (Denmark)

    Lebedeva, Elena R; Gurary, Natalia M; Sakovich, Vladimir P


    Rupture of a saccular intracranial aneurysm (SIA) causes thunderclap headache but it remains unclear whether headache in general and migraine in particular are more prevalent in patients with unruptured SIA.......Rupture of a saccular intracranial aneurysm (SIA) causes thunderclap headache but it remains unclear whether headache in general and migraine in particular are more prevalent in patients with unruptured SIA....

  16. Slip-pulse rupture behavior on a 2 meter granite fault (United States)

    McLaskey, Gregory C.; Kilgore, Brian D.; Beeler, Nicholas M.


    We describe observations of dynamic rupture events that spontaneously arise on meter-scale laboratory earthquake experiments. While low-frequency slip of the granite sample occurs in a relatively uniform and crack-like manner, instruments capable of detecting high frequency motions show that some parts of the fault slip abruptly (velocity >100 mm∙s-1, acceleration >20 km∙s-2) while the majority of the fault slips more slowly. Abruptly slipping regions propagate along the fault at nearly the shear wave speed. We propose that the dramatic reduction in frictional strength implied by this pulse-like rupture behavior has a common mechanism to the weakening reported in high velocity friction experiments performed on rotary machines. The slip pulses can also be identified as migrating sources of high frequency seismic waves. As observations from large earthquakes show similar propagating high frequency sources, the pulses described here may have relevance to the mechanics of larger earthquakes.

  17. Rupture characteristics of the 2016 Meinong earthquake revealed by the back projection and directivity analysis of teleseismic broadband waveforms (United States)

    Jian, Pei-Ru; Hung, Shu-Huei; Meng, Lingsen; Sun, Daoyuan


    The 2016 Mw 6.4 Meinong earthquake struck a previously unrecognized fault zone in midcrust beneath south Taiwan and inflicted heavy causalities in the populated Tainan City about 30 km northwest of the epicenter. Because of its relatively short rupture duration and P wave trains contaminated by large-amplitude depth phases and reverberations generated in the source region, accurate characterization of the rupture process and source properties for such a shallow strong earthquake remains challenging. Here we present a first high-resolution MUltiple SIgnal Classification back projection source image by using both P and depth-phase sP waves recorded at two large and dense arrays to understand the source behavior and consequent hazards of this peculiar catastrophic event. The results further corroborated by the directivity analysis indicate a unilateral rupture propagating northwestward and slightly downward on the shallow NE-dipping fault plane. The source radiation process is primarily characterized by one single peak, 7 s duration, with a total rupture length of 17 km and average rupture speed of 2.4 km/s. The rupture terminated immediately east of the prominent off-fault aftershock cluster about 20 km northwest of the hypocenter. Synergistic amplification of ground shaking by the directivity and strong excitation of sP and reverberations mainly caused the destruction concentrated in the area further to the northwest away from the rupture zone.

  18. [Premature rupture of membranes and chorioamnionitis]. (United States)

    Lopez Garcia, R


    Despite advances in perinatal medicine in the past decade, the diagnosis and treatment of premature rupture of membranes remain controversial. Premature rupture occurs in 2.7-7.0% of pregnancies and most cases occur spontaneously without apparent cause. The disparity in reported rates of premature rupture is due to differences in the definition and diagnostic criteria for premature rupture and lack of comparability in the populations studied. Mexico's National Institute of Perinatology has adopted the definition of the American COllege of Gynecology and Obstetrics which views premature rupture as that occurring before regular uterine contractions that produce cervical dilation. 8.8% of its patients have premature rupture according to this definition. 20% of cases occur before the 36th week of pregnancy. Treatment of rupture occurring before 37 weeks must balance the threat of amniotic infection with the dangers of premature birth. Infections appear more common in low income patient populations. Chorioamnionitis is a serious complication of pregnancy and is the main argument against conservative treatment of premature rupture. The rate of maternal infection is directly related to the time elapsing between rupture of the membranes and birth. The rate increases after the 1st 24 hours and is at least 10 times higher after 72 hours. But recent studies suggest that there is no considerable increase in infection if vaginal explorations are avoided and careful techniques are used in treating the patient. Those who advise conservative treatment believe that prenatal outcomes are better because respiratory disease syndrome due to prematurity is avoided. Conservative management requires a white cell count at least every 24 hours and measurement of pulse, maternal temperature, and fetal heart rate ideally every 4 hours. Perinatal mortality rates due to premature rupture of membranes range from 2.5-50%. The principal causes are respiratory disease syndrome, infection, asphyxia

  19. Simultaneous bilateral patellar tendon rupture without

    Directory of Open Access Journals (Sweden)

    LU Hua-ding


    Full Text Available 【Abstract】There is a dearth of case reports de-scribing simultaneous bilateral patellar tendon ruptures in the medical literature. These ruptures are often associated with systemic disorders such as lupus erythematosus or chronic steroid use. The author describes a case of a 24-year-old man who sustained traumatic bilateral patellar ten-don ruptures without any history of systemic disease or steroidal medication. We repaired and reattached the rup-tured tendons to the patella and augmented our procedure with allogeneic tendon followed by wire loop reinforcement. One year after operation, the patient regained a satisfactory range of motion of both knees with good quadriceps strength and no extensor lag. The recurrent microtrauma from a history of intense sports activity and a high body mass index may have played an important role in this trauma event. Key words: Patella; Patellar ligament; Rupture; Ten-don injuries; Knee

  20. Should the ruptured renal allograft be removed? (United States)

    Dryburgh, P; Porter, K A; Krom, R A; Uchida, K; West, J C; Weil, R; Starzl, T E


    During a 16-month period when 93 renal transplants were performed, eight kidney graft ruptures were detected within 18 days of transplantation, without evidence of venous obstruction. Six grafts were removed at the time of an exploratory operation for rupture and only one showed signs of probable irreversible rejection when examined by microscopy. Two graft ruptures were repaired and one of these grafts has had good long-term function 22 months later. These observations suggest that if bleeding at the site of grafts has had good long-term function 22 months later. These observations suggest that if bleeding at the site of graft rupture can be securely controlled and if the conditions of the patient and of the graft are favorable except for the rupture, it may be possible to save more than one of eight grafts.

  1. Derivation of XBIEM Kernels for Anti-plane/In-plane Problems and Implementation in Anti-plane Rupture Simulation Crossing Bimaterial Interface (United States)

    Kusakabe, T.; Kame, N.


    We develop an extended boundary integral equation method (XBIEM) to analyse dynamic behavior of rupture crossing a medium interface in 2D. Many faults often lie near medium interfaces in the Earth's heterogeneous crust consisting of various types of rocks. Some faults cross the interfaces, and the theoretical analysis of their dynamic behavior has been awaited. In the development, we focus on the extended parts of XBIEM in comparison to the conventional BIEM, and derive all the 2D displacement and stress kernels in response to a unit boundary traction in explicit discretized forms, which are the ingredients in the extension of BIEM. The final forms of kernels are compact and easy to evaluate numerically. They are implemented in simulating dynamic anti-plane rupture propagation across a bimaterial interface allowing secondary interfacial rupture. Our analysis shows a significant effect of an interfacial medium contrast on the control of dynamic rupture propagation.

  2. Dynamic earthquake rupture simulations on nonplanar faults embedded in 3D geometrically complex, heterogeneous elastic solids

    Energy Technology Data Exchange (ETDEWEB)

    Duru, Kenneth, E-mail: [Department of Geophysics, Stanford University, Stanford, CA (United States); Dunham, Eric M. [Department of Geophysics, Stanford University, Stanford, CA (United States); Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA (United States)


    Dynamic propagation of shear ruptures on a frictional interface in an elastic solid is a useful idealization of natural earthquakes. The conditions relating discontinuities in particle velocities across fault zones and tractions acting on the fault are often expressed as nonlinear friction laws. The corresponding initial boundary value problems are both numerically and computationally challenging. In addition, seismic waves generated by earthquake ruptures must be propagated for many wavelengths away from the fault. Therefore, reliable and efficient numerical simulations require both provably stable and high order accurate numerical methods. We present a high order accurate finite difference method for: a) enforcing nonlinear friction laws, in a consistent and provably stable manner, suitable for efficient explicit time integration; b) dynamic propagation of earthquake ruptures along nonplanar faults; and c) accurate propagation of seismic waves in heterogeneous media with free surface topography. We solve the first order form of the 3D elastic wave equation on a boundary-conforming curvilinear mesh, in terms of particle velocities and stresses that are collocated in space and time, using summation-by-parts (SBP) finite difference operators in space. Boundary and interface conditions are imposed weakly using penalties. By deriving semi-discrete energy estimates analogous to the continuous energy estimates we prove numerical stability. The finite difference stencils used in this paper are sixth order accurate in the interior and third order accurate close to the boundaries. However, the method is applicable to any spatial operator with a diagonal norm satisfying the SBP property. Time stepping is performed with a 4th order accurate explicit low storage Runge–Kutta scheme, thus yielding a globally fourth order accurate method in both space and time. We show numerical simulations on band limited self-similar fractal faults revealing the complexity of rupture

  3. Rupture of the 2004 Sumatra-Andaman earthquake inferred from direct P-wave imaging

    Institute of Scientific and Technical Information of China (English)

    LIU Ning; CHEN QiFu; NIU FengLin; CHEN Yong


    The Sumatra-Andaman earthquake on December 26, 2004 is the first well recorded gigantic earthquake (moment magnitude MW 9.3) by modern broadband seismic and Global Positioning System networks. The rich seismic and geodetic recordings have documented unprecedented details about the earthquake rupture, coseismic and postseismic deformations. This is a report of detailed images of the rupture process using the first-arriving compressional waves recorded by the China National Digital Seismic Network (CNDSN). An improved imaging condition was employed to account for the sparse distribution of the CNDSN stations. The resulting images are consistent with the major rupture features reported by previous seismic and geodetic studies. It is found that the earthquake rupture initiated at offshore of northwestern Sumatra and propagated in the north northwest direction at a speed of 2.7 ± 0.2 km/s. The rupture continued for at least 420 s and extended about 1200-1300 km along the Andaman trough with two bursts of seismic energy.

  4. Simplified approach for design of raft foundations against fault rupture. Part Ⅱ: soil-structure interaction

    Institute of Scientific and Technical Information of China (English)

    I. Anastasopoulos; N. Gerolymos; G. Gazetas; M. F. Bransby


    This is the second paper of two, which describe the results of an integrated research effort to develop afour-step simplified approach for design of raft foundations against dip-slip (normal and thrust) fault rupture. The first twosteps dealing with fault rupture propagation in the free-field were presented in the companion paper. This paper develops anapproximate analytical method to analyze soil-foundation-structure interaction (SFSI), involving two additional phenomena:(i) fault rupture diversion (Step 3); and (ii) modification of the vertical displacement profile (Step 4). For the first phenomenon(Step 3), an approximate energy-based approach is developed to estimate the diversion of a fault rupture due to presence ofa raft foundation. The normalized critical load for complete diversion is shown to be a function of soil strength, coefficient ofearth pressure at rest, bedrock depth, and the horizontal position of the foundation relative to the outcropping fault rupture.For the second phenomenon (Step 4), a heuristic approach is proposed, which "scans" through possible equilibrium positionsto detect the one that best satisfies force and moment equilibrium. Thus, we account for the strong geometric nonlinearitiesthat govern this interaction, such as uplifting and second order (P-A) effects. Comparisons with centrifuge-validated finiteelement analyses demonstrate the efficacy of the method. Its simplicity makes possible its utilization for preliminary design.

  5. Effects of Heterogeneities in Strength and Initial Shear Stress on Large Ruptures in a Fast Multi-cycle Earthquake Simulator (RSQSim) and DYNA3D (United States)

    Stevens, J.; Richards-Dinger, K.; Dieterich, J.; Oglesby, D.


    RSQSim is a fast earthquake simulator that produces long (~ 106 event and ~ 104 year) synthetic seismicity catalogs in complex fault systems. It treats the interseismic and nucleation phases of the seismic cycle quasi-statically with an approximate version of rate- and state-dependent friction. The ruptures themselves are quasi-dynamic with slip speeds determined by shear impedance considerations. Validation of coseismic final slip (and therefore stress change) distributions is important for the generation of long catalogs because subsequent events in such simulators need to inherit the proper stress fields. Also, the heterogeneous evolved stress states from long simulations in complex fault systems (resulting from complex large ruptures, ongoing smaller seismicity, and stress interactions within the fault system) may be useful as more realistic inputs to dynamic rupture modelling. If the time evolution of ruptures in RSQSim is also realistic, they may be useful as kinematic sources for seismic hazard ground motion calculations. As part of an effort to validate the quasi-dynamic ruptures in RSQSim, we compare rupture propagation on a variable-strength planar fault in RSQSim to that on a similar fault in DYNA3D (a fully dynamic finite element model employing slip-weakening friction) for single, large, artificially nucleated ruptures. Previous work has shown that on homogeneous planar faults the RSQSim results agreed quantitatively very well with those of DYNA3D. For this comparison, our asperity model consists of multiple rectangular zones of increased normal stress of varying size, location, and amplitude. The heterogeneities produce complex ruptures - the rupture front tends to wrap itself around the barriers and create a burst of energy once it propagates across a barrier. Both codes allow rupture propagation over significant zones of negative stress drop in these asperity regions. Rupture durations, average rupture propagation speeds, and overall slip pattern

  6. Complex rupture of an apparently simple asperity during the 2014/04/01 Pisagua earthquake (Northern Chile, Mw=8.1) (United States)

    Vallée, Martin; Grandin, Raphaël; Ruiz, Sergio; Delouis, Bertrand; Vigny, Christophe; Rivera, Efrain; Aissaoui, El-Madani; Allgeyer, Sébastien; Blétery, Quentin; Satriano, Claudio; Poiata, Natalia; Bernard, Pascal; Vilotte, Jean-Pierre; Schurr, Bernd


    We analyze the 2014/04/01 Pisagua earthquake with an extensive dataset, including dense inland observations (strong motion and GPS data, used both for their static and dynamic displacements), teleseismic data (P waves, SH waves, and high-frequency surface waves modeled through an empirical Green function approach) and tsunami data. The obtained kinematic source model is also validated a posteriori with InSAR data, for which the main aftershock (2014/04/03, Mw7.6) is taken into account. Data directly sensitive to the final displacement of the earthquake (static GPS, tsunami data and InSAR) well constrain a simple slip patch mostly located south of the hypocenter, half way between the coast and the trench. However, waveform data require that this patch has been broken in a complex way, involving an initial downdip rupture propagation followed by an updip propagation starting ~30s after rupture initiation. After this episode, during which most of the seismic moment is released, rupture still proceeds north of the hypocenter. This model reconciles the high-frequency imaging of the earthquake with back-propagation techniques, which are mostly sensitive to the initial downdip rupture propagation, with the low-frequency rupture process characterized by a slow propagation toward the South. The Pisagua earthquake illustrates how the rupture velocity of an earthquake can appear slow without being really so. This rupture process further documents the heterogeneous nature (in terms of stress or friction law) of this segment of the Chilean subduction zone, already imaged by the abundance of foreshocks which were unable to grow in a large event.

  7. A damage-mechanics model for fracture nucleation and propagation

    CERN Document Server

    Yakovlev, G; Turcotte, D L; Rundle, J B; Klein, W; 10.1016/j.tafmec.2010.06.002.


    In this paper a composite model for earthquake rupture initiation and propagation is proposed. The model includes aspects of damage mechanics, fiber-bundle models, and slider-block models. An array of elements is introduced in analogy to the fibers of a fiber bundle. Time to failure for each element is specified from a Poisson distribution. The hazard rate is assumed to have a power-law dependence on stress. When an element fails it is removed, the stress on a failed element is redistributed uniformly to a specified number of neighboring elements in a given range of interaction. Damage is defined to be the fraction of elements that have failed. Time to failure and modes of rupture propagation are determined as a function of the hazard-rate exponent and the range of interaction.

  8. Source rupture process inversion of the 2013 Lushan earthquake, China

    Directory of Open Access Journals (Sweden)

    Zhang Lifen


    Full Text Available The spatial and temporal slip distribution of the Lushan earthquake was estimated using teleseismic body wave data. To perform a stable inversion, we applied smoothing constraints and determined their optimal relative weights on the observed data using an optimized Akaike’s Bayesian Information Criterion (ABIC. The inversion generated the source parameters. Strike, dip and slip were 218°, 39° and 100. 8°, respectively. A seismic moment (M0 was 2. 1 × 1020 Nm with a moment magnitude (Mw of 6. 8, and a source duration was approximately 30 second. The rupture propagated along the dip direction, and the maximum slip occurred at the hypocenter. The maximum slip was approximately 2. 1 m, although this earthquake did not cause an apparent surface rupture. The energy was mainly released within 10 second. In addition, the Lushan earthquake was apparently related to the 2008 Wenchuan earthquake. However, the question of whether it was an aftershock of the Wenchuan earthquake requires further study.

  9. Rupture and frequency-dependent seismic radiation of the 2012 Mw 8.6 Sumatra strike-slip earthquake (United States)

    Yin, Jiuxun; Yao, Huajian


    On 2012 April 11, a great strike-slip earthquake (moment magnitude of Mw 8.6) occurred off the west coast of northern Sumatra area followed by an Mw 8.2 aftershock 2 hr later. Different geophysical data and methods have been used to investigate the mechanism, faulting, seismic radiation and slip propagation of this event, but frequency-dependent features of its rupture process have not been discussed much. In this study, we use a compressive sensing method based on sparsity inversion in the frequency domain to study the frequency-dependent seismic radiation and rupture process of this event. Our results indicate a very complex rupture process concerning at least three different rupture stages on multiple subfaults with nearly conjugate geometries. The main shock has triggered seismicity on a series of ridge-perpendicular or ridge-parallel conjugate strike-slip faults around the Nighty East Ridge. Obvious frequency-dependent rupture process has been presented and discussed. Combining results from slip inversion based on the finite-fault model, we observe that in the beginning stage of the rupture lower frequency radiation appears to originate from the areas with large slip, while the high-frequency radiation is located at the boundary of large-slip region or rupture front. Some radiation probably originates from the repeating slip on the main faults or triggered events on some nearby faults in the rupture area. The complex frequency-dependent seismic radiation patterns observed in this study provide important information for future investigation of rupture physics of this complex strike-slip event.

  10. Rupture processes of the 2015 Mw 7.9 Gorkha earthquake and its Mw 7.3 aftershock and their implications on the seismic risk (United States)

    Liu, Chengli; Zheng, Yong; Wang, Rongjiang; Shan, Bin; Xie, Zujun; Xiong, Xiong; Ge, Can


    The rupture processes of the 2015 April 25 Gorkha earthquake and its strongest aftershock occurred on May 12 in Nepal are investigated by joint inversion of seismological and geodetic data. Synthetic test shows that the sedimentary layers in the source region play an important role in the rupture process inversion. Our optimized model of the mainshock shows that the rupture has a unilateral propagation pattern. The dominant mechanism is pure thrust with maximum slip of 5.8 m, the rupture scale extends ~ 60 km along dip and ~ 150 km along strike, and the largest static stress change is ~ 7.6 MPa. The total seismic moment is 7.87 × 1020 N m, equivalent to Mw 7.9. Most seismic moment was released within 80 s and the majority seismic moment was released at the first 40 s. The rupture propagated in main slip asperity with a velocity of ~ 3.0 km/s. The strong aftershock magnitude is about Mw 7.3, and the peak slip is about 5.0 m, close to the peak slip of the mainshock. Moreover, the slips of the mainshock and the aftershocks are in good complementary, suggesting a triggering relationship between them. Considering the strain accumulation, the Gorkha earthquake ruptured only part of the seismic gap alone, thus still poses high earthquake risk, especially in the west side of the mainshock rupture zone.

  11. Viscothermal wave propagation

    NARCIS (Netherlands)

    Nijhof, Marten Jozef Johannes


    In this work, the accuracy, efficiency and range of applicability of various (approximate) models for viscothermal wave propagation are investigated. Models for viscothermal wave propagation describe thewave behavior of fluids including viscous and thermal effects. Cases where viscothermal effects a

  12. Misdiagnosed Chest Pain: Spontaneous Esophageal Rupture (United States)

    Inci, Sinan; Gundogdu, Fuat; Gungor, Hasan; Arslan, Sakir; Turkyilmaz, Atila; Eroglu, Atila


    Chest pain is one of themost common complaints expressed by patients presenting to the emergency department, and any initial evaluation should always consider life-threatening causes. Esophageal rupture is a serious condition with a highmortality rate. If diagnosed, successful therapy depends on the size of the rupture and the time elapsed between rupture and diagnosis.We report on a 41-year-old woman who presented to the emergency department complaining of left-sided chest pain for two hours. PMID:27122690

  13. Patellar tendon: From tendinopathy to rupture

    Directory of Open Access Journals (Sweden)

    Federica Rosso


    Full Text Available Patellar tendinopathy is very common in patients complaining of anterior knee pain. Its aetiology is still unclear, but neovascularisation seems to play a role. Different treatments have been proposed overtime, from rehabilitation to platelet-rich-plasma injections, but there is no agreement on the best treatment protocol. The final stage of patellar tendinopathy is patellar tendon rupture. In these cases surgical treatment is often required. The aim of this literature review is to focus on the aetiology, diagnosis, and treatment of both patellar tendinopathy and rupture. We report the conservative treatments proposed for patellar tendinopathy and the surgical techniques described for its rupture.

  14. Plantar fascia rupture: diagnosis and treatment. (United States)

    Rolf, C; Guntner, P; Ericsäter, J; Turan, I


    Two patients with spontaneous medial plantar fascia rupture due to a definite injury with no prior symptoms, were referred to our institution. Clinically, there was a tender lump in the sole, and magnetic resonance imaging confirmed the diagnosis. Nonoperative treatment was sufficient in curing the acute total rupture. Endoscopic release was used on the partially ruptured plantar fascia, but it is probably more optimal in the acute phase. The literature provides no comparative data on operative or nonoperative treatment efficacy for this rare condition.


    Directory of Open Access Journals (Sweden)

    Vijay Kumar


    Full Text Available Unicornuate uterus can sometimes be associated with rudimentary horn. Pregnancy in a rudimentary horn is rare and usually ends up in rupture. Diagnosis is difficult and can be missed in routine ultrasound scan and is usually detected after rupture. We report a case of G1P1 with rudimentary horn pregnancy which raised suspicion on ultr asound and was later diagnosed by MR imaging. Patient refused termination and presented next day with shock. Laparotomy revealed ruptured right rudimentary horn pregnancy.

  16. Gastric rupture after the Heimlich maneuver. (United States)

    Bintz, M; Cogbill, T H


    Since 1975, the Heimlich maneuver has been widely applied to relieve upper airway obstruction caused by aspirated material. Life-threatening complications have been documented following this simple procedure. We report two cases of gastric rupture after use of the Heimlich maneuver. Both patients experienced pulmonary and abdominal symptoms. The diagnosis was confirmed in each case by the demonstration of free intraperitoneal air on an upright chest roentgenogram. Full-thickness gastric rupture along the lesser curvature of the stomach was repaired in both patients; one patient died. Abdominal pain or persistent abdominal distention despite nasogastric suction after the Heimlich maneuver should prompt evaluation for possible gastric rupture.

  17. Stress analysis of fracture of atherosclerotic plaques: crack propagation modeling. (United States)

    Rezvani-Sharif, Alireza; Tafazzoli-Shadpour, Mohammad; Kazemi-Saleh, Davood; Sotoudeh-Anvari, Maryam


    Traditionally, the degree of luminal obstruction has been used to assess the vulnerability of atherosclerotic plaques. However, recent studies have revealed that other factors such as plaque morphology, material properties of lesion components and blood pressure may contribute to the fracture of atherosclerotic plaques. The aim of this study was to investigate the mechanism of fracture of atherosclerotic plaques based on the mechanical stress distribution and fatigue analysis by means of numerical simulation. Realistic models of type V plaques were reconstructed based on histological images. Finite element method was used to determine mechanical stress distribution within the plaque. Assuming that crack propagation initiated at the sites of stress concentration, crack propagation due to pulsatile blood pressure was modeled. Results showed that crack propagation considerably changed the stress field within the plaque and in some cases led to initiation of secondary cracks. The lipid pool stiffness affected the location of crack formation and the rate and direction of crack propagation. Moreover, increasing the mean or pulse pressure decreased the number of cycles to rupture. It is suggested that crack propagation analysis can lead to a better recognition of factors involved in plaque rupture and more accurate determination of vulnerable plaques.

  18. Spontaneous rupture of ovarian cystadenocarcinoma: pre- and post-rupture computed tomography evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Salvadori, Priscila Silveira; Atzingen, Augusto Castelli von; D' Ippolito, Giuseppe [Universidade Federal de Sao Paulo (EPM/UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina; Bomfim, Lucas Novais [Universidade Tiradentes (UNIT), Maceio, AL, (Brazil)


    Epithelial ovarian tumors are the most common malignant ovarian neoplasms and, in most cases, eventual rupture of such tumors is associated with a surgical procedure. The authors report the case of a 54-year-old woman who presented with spontaneous rupture of ovarian cystadenocarcinoma documented by computed tomography, both before and after the event. In such cases, a post-rupture staging tends to be less favorable, compromising the prognosis. (author)

  19. Creep-rupture reliability analysis (United States)

    Peralta-Duran, A.; Wirsching, P. H.


    A probabilistic approach to the correlation and extrapolation of creep-rupture data is presented. Time temperature parameters (TTP) are used to correlate the data, and an analytical expression for the master curve is developed. The expression provides a simple model for the statistical distribution of strength and fits neatly into a probabilistic design format. The analysis focuses on the Larson-Miller and on the Manson-Haferd parameters, but it can be applied to any of the TTP's. A method is developed for evaluating material dependent constants for TTP's. It is shown that optimized constants can provide a significant improvement in the correlation of the data, thereby reducing modelling error. Attempts were made to quantify the performance of the proposed method in predicting long term behavior. Uncertainty in predicting long term behavior from short term tests was derived for several sets of data. Examples are presented which illustrate the theory and demonstrate the application of state of the art reliability methods to the design of components under creep.

  20. Adaptive, High-Order, and Scalable Software Elements for Dynamic Rupture Simulations in Complex Geometries (United States)

    Kozdon, J. E.; Wilcox, L.; Aranda, A. R.


    The goal of this work is to develop a new set of simulation tools for earthquake rupture dynamics based on state-of-the-art high-order, adaptive numerical methods capable of handling complex geometries. High-order methods are ideal for earthquake rupture simulations as the problems are wave-dominated and the waves excited in simulations propagate over distance much larger than their fundamental wavelength. When high-order methods are used for such problems significantly fewer degrees of freedom are required as compared with low-order methods. The base numerical method in our new software elements is a discontinuous Galerkin method based on curved, Kronecker product hexahedral elements. We currently use MPI for off-node parallelism and are in the process of exploring strategies for on-node parallelism. Spatial mesh adaptivity is handled using the p4est library and temporal adaptivity is achieved through an Adams-Bashforth based local time stepping method; we are presently in the process of including dynamic spatial adaptivity which we believe will be valuable for capturing the small-scale features around the propagating rupture front. One of the key features of our software elements is that the method is provably stable, even after the inclusion of the nonlinear frictions laws which govern rupture dynamics. In this presentation we will both outline the structure of the software elements as well as validate the rupture dynamics with SCEC benchmark test problems. We are also presently developing several realistic simulation geometries which may also be reported on. Finally, the software elements that we have designed are fully public domain and have been designed with tightly coupled, wave dominated multiphysics applications in mind. This latter design decisions means the software elements are applicable to many other geophysical and non-geophysical applications.

  1. Achilles tendon rupture in atypical patient populations. (United States)

    Kingsley, Peter


    Rupture of the Achilles tendon is a significant injury, and the likelihood of a good recovery is directly associated with early diagnosis and appropriate referral. Such injuries are commonly assessed and identified by practitioners working in 'minors' areas of emergency departments or urgent care settings. The literature frequently describes rupture of the Achilles tendon as 'typically sport-related' affecting 'middle-aged weekend warriors', but this aetiology accounts for only about 70% of such injuries. Factors such as the natural ageing process, obesity and use of some commonly prescribed medications, can increase the risk of developing a tendinopathy and subsequent rupture, often from a seemingly insignificant incident. However, research suggests that injuries in this patient population are more likely be missed on first examination. This article describes risk factors that should alert clinicians to the possibility of Achilles tendon rupture in 'atypical' patient populations.

  2. Spontaneous splenic rupture in typhoid fever.


    Ali, G; Kamili, M. A.; Rashid, S; Mansoor, A; Lone, B. A.; Allaqaband, G. Q.


    Three cases of multidrug-resistant Salmonella typhi infection presenting as spontaneous splenic rupture are presented. One patient died and two recovered completely. This is a previously unreported presentation of typhoid fever.

  3. Right Diaphragm Spontaneous Rupture: A Surgical Approach

    Directory of Open Access Journals (Sweden)

    Duilio Divisi


    Full Text Available We present a case of spontaneous rupture of the diaphragm, characterized by nonspecific symptoms. The rapid diagnosis and appropriate surgical approach led to a positive resolution of the pathology.

  4. Cognitive frames in psychology: demarcations and ruptures. (United States)

    Yurevich, Andrey V


    As there seems to be a recurrent feeling of crisis in psychology, its present state is analyzed in this article. The author believes that in addition to the traditional manifestations that have dogged psychology since it emerged as an independent science some new features of the crisis have emerged. Three fundamental "ruptures" are identified: the "horizontal" rupture between various schools and trends, the "vertical" rupture between natural science and humanitarian psychology, and the "diagonal" rupture between academic research and applied practice of psychology. These manifestations of the crisis of psychology have recently been compounded by the crisis of its rationalistic foundations. This situation is described in terms of the cognitive systems in psychology which include meta-theories, paradigms, sociodigms and metadigms.

  5. Uterine rupture without previous caesarean delivery

    DEFF Research Database (Denmark)

    Thisted, Dorthe L. A.; H. Mortensen, Laust; Krebs, Lone


    .3/100,000 deliveries. Multiparity (RR 8.99 (95% CI 1.86-43.29)), induction of labour (RR 3.26 (95% CI 1.24-8.57)), epidural analgesia (RR 10.78 (95% CI 4.25-27.39)), and augmentation by oxytocin (RR 9.50 (95% CI 3.15-28.63)) were associated with uterine rupture. Induction of labour was not significantly related...... to uterine rupture when adjusted for parity, epidural analgesia and augmentation by oxytocin. CONCLUSION: Although uterine rupture is rare, its association with epidural analgesia and augmentation of labour with oxytocin in multipara should be considered. Thus, vigilance should be exercised when labour...... is obstructed and there is need for epidural analgesia and/or augmentation by oxytocin in multiparous women. Due to the rare occurrence of uterine rupture caution should be exerted when interpreting the findings of this study....

  6. Micromechanical properties and collagen composition of ruptured human achilles tendon

    DEFF Research Database (Denmark)

    Hansen, Philip; Kovanen, Vuokko; Hölmich, Per


    The Achilles tendon is one of the strongest tendons in the human body, and yet it frequently ruptures, which is a substantial clinical problem. However, the cause of ruptures remains elusive.......The Achilles tendon is one of the strongest tendons in the human body, and yet it frequently ruptures, which is a substantial clinical problem. However, the cause of ruptures remains elusive....

  7. Quadriceps tendon rupture through a superolateral bipartite patella. (United States)

    Woods, G William; O'Connor, Daniel P; Elkousy, Hussein A


    We report a case of a quadriceps tendon rupture through a bipartite patella. Although quadriceps tendon ruptures and patella fractures are common, rupture through a bipartite patella fragment is rare. This case was managed similar to a quadriceps rupture with an excellent result.

  8. Aortic ruptures in seat belt wearers. (United States)

    Arajärvi, E; Santavirta, S; Tolonen, J


    Several investigations have indicated that rupture of the thoracic aorta is one of the leading causes of immediate death in victims of road traffic accidents. In Finland in 1983, 92% of front-seat passengers were seat belt wearers on highways and 82% in build-up areas. The mechanisms of rupture of the aorta have been intensively investigated, but the relationship between seat belt wearing and injury mechanisms leading to aortic rupture is still largely unknown. This study comprises 4169 fatally injured victims investigated by the Boards of Traffic Accident Investigation of Insurance Companies during the period 1972 to 1985. Chest injuries were recorded as the main cause of death in 1121 (26.9%) victims, 207 (5.0%) of those victims having worn a seat belt. Aortic ruptures were found at autopsy in 98 victims and the exact information of the location of the aortic tears was available in 68. For a control group, we analyzed 72 randomly chosen unbelted victims who had a fatal aortic rupture in similar accidents. The location of the aortic rupture in unbelted victims was more often in the ascending aorta, especially in drivers, whereas in seat belt wearers the distal descending aorta was statistically more often ruptured, especially in right-front passengers (p less than 0.05). The steering wheel predominated statistically as the part of the car estimated to have caused the injury in unbelted victims (37/72), and some interior part of the car was the most common cause of fatal thoracic impacts in seat belt wearers (48/68) (p less than 0.001). The mechanism of rupture of the aorta in the classic site just distal to the subclavian artery seems to be rapid deceleration, although complex body movements are also responsible in side impact collisions. The main mechanism leading to rupture of the ascending aorta seems to be severe blow to the bony thorax. This also often causes associated thoracic injuries, such as heart rupture and sternal fracture. Injuries in the ascending

  9. Blunt cardiac rupture in a toddler

    Directory of Open Access Journals (Sweden)

    Peep Talving


    Full Text Available Blunt cardiac rupture is typically a fatal injury with overall mortality exceeding 90%. Most of the patients never reach the hospital alive. In pediatric patients, only 0.03% of cases following blunt trauma admissions have a cardiac injury. This report presents a rare survivor of 16-months old toddler injured in a domestic accident suffering a right atrial rupture repaired through a median sternotomy. To the best of our knowledge this is the youngest case reported in the literature.

  10. Investigations Into Early Magnitude Estimation From Predominant Period, Using Synthetic Rupture Models (United States)

    Hildyard, M.; Rietbrock, A.


    Considerable interest has been shown in a method for estimating predominant period in the time domain (TpMax), first proposed by Nakamura (1988) and currently being developed for other early warning systems (e.g. Lockman and Allen, BSSA, 2005). Issues still exist as to the causes of the scatter evident in empirical work, and how effective the method is for characterising large events whose time to rupture is longer than the few seconds desired to estimate the magnitude. Our work on applying this method to an aftershock dataset motivated us to investigate the method through the use of synthetic rupture models. The rupture model we use prescribes a stress-drop with a prescribed rise-time over a small patch of the fault surface. This stress-drop is propagated to other patches of the fault according to a prescribed rupture rate. The same finite difference model geometry and fault patch size was then used to model events ranging from magnitude 3.7 to 7.2. Moment Magnitude was calculated directly by integrating the resultant slip on the fault, and TpMax was calculated from seismograms recorded on surface 50 km from the centre of the fault. The initial modelling used a homogenous stress drop, rise-time, and rupture rate. A dataset of 165 events, showed a significant increasing relationship between the TpMax calculation and magnitude. Isolating similar events initiating at the same point on the fault, gave a near straight-line trend. Scatter in the relationship is shown to result from variations in the position, initiation point, stress drop, rise time, and rupture velocity. Low frequency filtering was found to significantly affect the TpMax calculations and trends. Without filtering, the relationship saturated from just after magnitude 6, as the time to rupture becomes longer than the window used to calculate TpMax. However, low frequency filtering actually reduces the time to reach a maximum in the calculation, and this can cause the increasing trend to continue into

  11. Distribution of surface rupture associated the 2016 Kumamoto earthquake and its significance (United States)

    Goto, H.; Kumahara, Y.; Tsutsumi, H.; Toda, S.; Ishimura, D.; Okada, S.; Nakata, T.; Kagohara, K.; Kaneda, H.; Suzuki, Y.; Watanabe, M.; Tsumura, S.; Matsuta, N.; Ishiyama, T.; Sugito, N.; Hirouchi, D.; Ishiguro, S.; Yoshida, H.; Tanaka, K.; Takenami, D.; Kashihara, S.; Tanaka, T.; Moriki, H.


    A Mj 6.5 earthquake hit Kumamoto prefecture, central Kyushu, southwest Japan at 21:26 JST on April 14th. About 28 hours after, The Mj 7.3 earthquake occurred at 01:25 JST on April 16, and caused severe shaking in and around the epicentral region. An ENE-to-NE-trending surface rupture zone associated with the earthquakes appeared along the previously mapped 100-km-long active fault called the Futagawa-Hinagu fault zone (FHFZ) (Watanabe et al., 1979; Research Group for Active Tectonics in Kyushu, 1989; Research Group for Active Faults of Japan, 1991; Ikeda et al., 2001; Nakata and Imaizumi ed, 2002). According to our field survey for three months, we found the 31-km-length surface rupture close to the traces of the northeastern part of the FHFZ, and another 5-km-length rupture on a part of the Denokuchi fault. The rupture along the FHFZ shows right-lateral strike slip mainly ( 2.1 m in maximum). The rupture on the Denokuchi fault, far from about 2km east of the FHFZ, is the normal component with down to northwest. These coseismic ruptures of the Mj 7.3 earthquake have been represented to be a characteristic movement of the northeastern part of the FHFZ. The deformations such as a series of the open cracks with NW-SE trending were traceable for a distance of 5.4 km from Kengun to Shirakawa River in and around the downtown of Kumamoto city. Those features followed on tectonic landform by the active fault and on the line of the fringe abnormal in InSAR image (Geospatial Information Authority of Japan, 2016) represent small triggered slip. The eyewitness of local resident and our observation revealed that a coseismic small rupture of the Mj 6.5 earthquake had been appeared along the southern end of Mj 7.3 earthquake ruptures. Seismic inversion theory (DPRI, Kyoto Univ, 2016) showed that the coseismic rupture propagated toward NE along the strike of the FHFZ, and an asperity near the surface was recognized from 10 km far from the epicenter toward NE. The area of maximum

  12. Perfect Derived Propagators

    CERN Document Server

    Schulte, Christian


    When implementing a propagator for a constraint, one must decide about variants: When implementing min, should one also implement max? Should one implement linear equations both with and without coefficients? Constraint variants are ubiquitous: implementing them requires considerable (if not prohibitive) effort and decreases maintainability, but will deliver better performance. This paper shows how to use variable views, previously introduced for an implementation architecture, to derive perfect propagator variants. A model for views and derived propagators is introduced. Derived propagators are proved to be indeed perfect in that they inherit essential properties such as correctness and domain and bounds consistency. Techniques for systematically deriving propagators such as transformation, generalization, specialization, and channeling are developed for several variable domains. We evaluate the massive impact of derived propagators. Without derived propagators, Gecode would require 140000 rather than 40000 ...

  13. Rupture directivity of fluid-induced microseismic events: Observations from an enhanced geothermal system (United States)

    Folesky, Jonas; Kummerow, Jörn; Shapiro, Serge A.; Häring, Markus; Asanuma, Hiroshi


    The rupture process of fluid-induced microseismic events is still poorly understood, mainly due to usually small magnitudes and sparse monitoring geometries. The high-quality recordings of the earthquake sequence 2006-2007 at the enhanced geothermal system at Basel, Switzerland, constitute a rare exception, allowing a systematic directivity study of 195 events using the empirical Green's function method. We observe clear directivity signatures for about half the events which demonstrates that rupture directivity persists down to small magnitudes (ML˜1). The predominant rupture behavior is unilateral. We further find evidence that directivity is magnitude dependent and varies systematically with distance from the injection source. Whereas pore pressure seems to play the dominant role close to the injection source and no preferred rupture direction is observable, directivity aligns parallel to the event distribution with increasing distance (≳100 m) and is preferably oriented away from the injection point. The largest analyzed events (ML˜2) show a distinct behavior: They rupture toward the injection source, suggesting that they nucleate in the vicinity of the pressure front and propagate backward into the perturbed volume. This finding is of particular relevance for seismic hazard assessment of georeservoirs, since it implies that maximum event size is related to dimension of the fluid-perturbed volume. Our study also resolves rupture complexities for a small group of events. This shows that small fault heterogeneities exist down to a scale of a few tens of meters. The observation of directivity and complexity in induced microseismic events suggest that future source studies account for these phenomena.


    Directory of Open Access Journals (Sweden)



    Full Text Available The membranes surrounding the amniotic cavity are composed from amnion and chorion, tightly adherent layers which are composed of several cell types, including epithelial cells, trophoblasts cells and mesenchyme cells, embedded in a collagenous matrix. They retain amniotic fluid, secret substances into the amniotic fluid, as well as to the uterus and protect the fetus against upward infections from urogenital tract. Normally, the membranes it breaks during labor. Premature rupture of the amniotic sac (PRAS is defined as rupture of membranes before the onset of labor. Premature rupture of the fetal membrane, which occurs before 37 weeks of gestation, usually, refers to preterm premature rupture of membranes. Despite advances in the care period, premature rupture of membranes and premature rupture of membranes preterm continue to be regarded as serious obstetric complications. On the term 8% - 10% of pregnant women have premature rupture of membranes; these women are at increased risk of intrauterine infections, where the interval between membrane rupture and expulsion is rolled-over. Premature rupture of membranes preterm occurs in approximately 1% of all pregnancies and is associated with 30% -40% of preterm births. Thus, it is important to identify the cause of pre-term birth (after less than 37 completed weeks of "gestation" and its complications, including respiratory distress syndrome, neonatal infection and intraventricular hemorrhage. Objectives: the development of the protocol of the clinical trial on patients with impending preterm birth, study clinical and statistical on the socio-demographic characteristics of patients with imminent preterm birth; clinical condition of patients and selection of cases that could benefit from the application of interventional therapy; preclinical investigation (biological and imaging of patients with imminent preterm birth; the modality therapy; clinical investigation of the effectiveness of short

  15. Validation of the rupture properties of the 2001 Kunlun, China (Ms = 8.1), earthquake from seismological and geological observations (United States)

    Wen, Y.-Y.; Ma, K.-F.; Song, T.R.-A.; Mooney, W.D.


    We determine the finite-fault slip distribution of the 2001 Kunlun earthquake (Ms = 8.1) by inverting teleseismic waveforms, as constrained by geological and remote sensing field observations. The spatial slip distribution along the 400-km-long fault was divided into five segments in accordance with geological observations. Forward modelling of regional surface waves was performed to estimate the variation of the speed of rupture propagation during faulting. For our modelling, the regional 1-D velocity structure was carefully constructed for each of six regional seismic stations using three events with magnitudes of 5.1-5.4 distributed along the ruptured portion of the Kunlun fault. Our result shows that the average rupture velocity is about 3.6 km s-1, consistent with teleseismic long period wave modelling. The initial rupture was almost purely strike-slip with a rupture velocity of 1.9 km s-1, increasing to 3.5 km s-1 in the second fault segment, and reaching a rupture velocity of about 6 km s-1 in the third segment and the fourth segment, where the maximum surface offset, with a broad fault zone, was observed. The rupture velocity decelerated to a value of 3.3 km s-1 in the fifth and final segment. Coseismic slip on the fault was concentrated between the surface and a depth of about 10 km. We infer that significant variations in rupture velocity and the observed fault segmentation are indicative of variations in strength along the interface of the Kunlun fault, as well as variations in fault geometry. ?? 2009 The Authors Journal compilation ?? 2009 RAS.

  16. The roentgenographic findings of achilles tendon rupture

    Energy Technology Data Exchange (ETDEWEB)

    Seouk, Kang Hyo; Keun, Rho Yong [Shilla General Hospital, Seoul (Korea, Republic of)


    To evaluate the diagnostic value of a lateral view of the ankles in Achilles tendon rupture. We performed a retrospective analysis of the roentgenographic findings of 15 patients with surgically proven Achilles tendon rupture. Four groups of 15 patients(normal, ankle sprain, medial lateral malleolar fracture, and calcaneal fracture) were analysed as reference groups. Plain radiographs were reviewed with regard to Kager's triangle, Arner's sign, Toygar's angle, ill defined radiolucent shadow through the Achilles tendon, sharpness of the anterior margin of Achilles tendon, and meniscoid smooth margin of the posterior skin surface of the ankle. Kager's triangle was deformed and disappeared after rupture of the Achilles tendon in nine patients(60%) with operative verification of the rupture, six patients(40%) had a positive Arner's sign, while none had a diminished Toygars angle. In 13 patients(87%) with a ruptured Achilles tendon, the thickness of this was nonuniform compared with the reference group. The anterior margin of the Achilles tendon became serrated and indistinct in 14 patients(93%) in whom this was ruptured. An abnormal ill defined radiolucent shadow through the Achilles tendon was noted in nine patient(60%), and nonparallelism between the anterior margin of the Achilles tendon and posterior skin surface of the ankle was detected in 11 patients(73%). The posterior skin surface of the ankle had a nodular surface margin in 13 patients(87%). A deformed Kager's triangle and Achilles tendon, and an abnormal ill defined radiolucent shadow through the Achilles tendon in a lateral view of the ankles are important findings for the diagnesis of in diagnosing achilles tendon rupture.

  17. General Considerations of Ruptured Abdominal Aortic Aneurysm: Ruptured Abdominal Aortic Aneurysm


    Lee, Chung Won; Bae, Miju; Chung, Sung Woon


    Although development of surgical technique and critical care, ruptured abdominal aortic aneurysm still carries a high mortality. In order to obtain good results, various efforts have been attempted. This paper reviews initial management of ruptured abdominal aortic aneurysm and discuss the key point open surgical repair and endovascular aneurysm repair.

  18. Strain-dependent Damage Evolution and Velocity Reduction in Fault Zones Induced by Earthquake Rupture (United States)

    Zhong, J.; Duan, B.


    Low-velocity fault zones (LVFZs) with reduced seismic velocities relative to the surrounding wall rocks are widely observed around active faults. The presence of such a zone will affect rupture propagation, near-field ground motion, and off-fault damage in subsequent earth-quakes. In this study, we quantify the reduction of seismic velocities caused by dynamic rup-ture on a 2D planar fault surrounded by a low-velocity fault zone. First, we implement the damage rheology (Lyakhovsky et al. 1997) in EQdyna (Duan and Oglesby 2006), an explicit dynamic finite element code. We further extend this damage rheology model to include the dependence of strains on crack density. Then, we quantify off-fault continuum damage distribution and velocity reduction induced by earthquake rupture with the presence of a preexisting LVFZ. We find that the presence of a LVFZ affects the tempo-spatial distribu-tions of off-fault damage. Because lack of constraint in some damage parameters, we further investigate the relationship between velocity reduction and these damage prameters by a large suite of numerical simulations. Slip velocity, slip, and near-field ground motions computed from damage rheology are also compared with those from off-fault elastic or elastoplastic responses. We find that the reduction in elastic moduli during dynamic rupture has profound impact on these quantities.

  19. Subducting plate geology in three great earthquake ruptures of the western Alaska margin, Kodiak to Unimak (United States)

    von Huene, Roland; Miller, John J.; Weinrebe, Wilhelm


    Three destructive earthquakes along the Alaska subduction zone sourced transoceanic tsunamis during the past 70 years. Since it is reasoned that past rupture areas might again source tsunamis in the future, we studied potential asperities and barriers in the subduction zone by examining Quaternary Gulf of Alaska plate history, geophysical data, and morphology. We relate the aftershock areas to subducting lower plate relief and dissimilar materials in the seismogenic zone in the 1964 Kodiak and adjacent 1938 Semidi Islands earthquake segments. In the 1946 Unimak earthquake segment, the exposed lower plate seafloor lacks major relief that might organize great earthquake rupture. However, the upper plate contains a deep transverse-trending basin and basement ridges associated with the Eocene continental Alaska convergent margin transition to the Aleutian island arc. These upper plate features are sufficiently large to have affected rupture propagation. In addition, massive slope failure in the Unimak area may explain the local 42-m-high 1946 tsunami runup. Although Quaternary geologic and tectonic processes included accretion to form a frontal prism, the study of seismic images, samples, and continental slope physiography shows a previous history of tectonic erosion. Implied asperities and barriers in the seismogenic zone could organize future great earthquake rupture.

  20. The Wheeler Propagator


    Bollini, C. G.; Rocca, M. C.


    We study the half advanced and half retarded Wheeler Green function and its relation to Feynman propagators. First for massless equation. Then, for Klein-Gordon equations with arbitrary mass parameters; real, imaginary or complex. In all cases the Wheeler propagator lacks an on-shell free propagation. The Wheeler function has support inside the light-cone (whatever the mass). The associated vacuum is symmetric with respect to annihilation and creation operators. We show with some examples tha...

  1. Light microscopic histology of quadriceps tendon ruptures. (United States)

    Maffulli, Nicola; Del Buono, Angelo; Spiezia, Filippo; Longo, Umile Giuseppe; Denaro, Vincenzo


    To assess histological changes and possible differences in the quadriceps of patients undergoing open repair of the tendon after spontaneous rupture, and subjects with no history of tendon pathology. Biopsies were harvested from the quadriceps tendon of 46 patients (34 men, 12 women) who had reported unilateral atraumatic quadriceps tendon rupture and had undergone surgical repair of the tendon. Samples were also harvested from both the tendons in 11 (N = 11 × 2) patients, nine males and two females, dying from cardiovascular disorders. For each tendon, three slides were randomly selected and examined under light microscopy, and assessed using a semiquantitative grading scale (range 0-21) which considers fibre structure, fibre arrangement, rounding of the nuclei, regional variations in cellularity, increased vascularity, decreased collagen stainability, and hyalinisation. The pathological sum-score averaged 19.2 ± 3.7 in ruptured tendons and 5.6 ± 2.0 in controls, and all variables considered were significantly different between the two groups, showing an association between tendon abnormalities and rupture (0.05 tendons increases the risk of rupture.

  2. Endovascular repair of ruptured abdominal aortic aneurysm

    Directory of Open Access Journals (Sweden)

    Šarac Momir


    Full Text Available Introduction. Rupture of an abdominal aortic aneurysm (AAA is a potentially lethal state. Only half of patients with ruptured AAA reach the hospital alive. The alternative for open reconstruction of this condition is endovascular repair (EVAR. We presented a successful endovascular reapir of ruptured AAA in a patient with a number of comorbidities. Case report. A 60-year-old man was admitted to our institution due to diffuse abdominal pain with flatulence and belching. Initial abdominal ultrasonography showed an AAA that was confirmed on multislice computed tomography scan angiography which revealed a large retroperitoneal haematoma. Because of patient’s comorbidites (previous surgery of laryngeal carcinoma and one-third laryngeal stenosis, arterial hypertension and cardiomyopathy with left ventricle ejection fraction of 30%, stenosis of the right internal carotid artery of 80% it was decided that endovascular repair of ruptured AAA in local anaesthesia and analgosedation would be treatment of choice. Endovascular grafting was achieved with aorto-bi-iliac bifurcated excluder endoprosthesis with complete exclusion of the aneurysmal sac, without further enlargment of haemathoma and no contrast leakage. The postoperative course of the patient was eventless, without complications. On recall examination 3 months after, the state of the patient was well. Conclusion. The alternative for open reconstruction of ruptured AAA in haemodynamically stable patients with suitable anatomy and comorbidities could be emergency EVAR in local anesthesia. This technique could provide greater chances for survival with lower intraoperative and postoperative morbidity and mortality, as shown in the presented patient.

  3. Dynamic rupture processes inferred from laboratory microearthquakes (United States)

    Passelègue, François. X.; Schubnel, Alexandre; Nielsen, Stefan; Bhat, Harsha S.; Deldicque, Damien; Madariaga, Raúl


    We report macroscopic stick-slip events in saw-cut Westerly granite samples deformed under controlled upper crustal stress conditions in the laboratory. Experiments were conducted under triaxial loading (σ1>σ2=σ3) at confining pressures (σ3) ranging from 10 to 100 MPa. A high-frequency acoustic monitoring array recorded particle acceleration during macroscopic stick-slip events allowing us to estimate rupture speed. In addition, we record the stress drop dynamically and we show that the dynamic stress drop measured locally close to the fault plane is almost total in the breakdown zone (for normal stress >75 MPa), while the friction f recovers to values of f > 0.4 within only a few hundred microseconds. Enhanced dynamic weakening is observed to be linked to the melting of asperities which can be well explained by flash heating theory in agreement with our postmortem microstructural analysis. Relationships between initial state of stress, rupture velocities, stress drop, and energy budget suggest that at high normal stress (leading to supershear rupture velocities), the rupture processes are more dissipative. Our observations question the current dichotomy between the fracture energy and the frictional energy in terms of rupture processes. A power law scaling of the fracture energy with final slip is observed over 8 orders of magnitude in slip, from a few microns to tens of meters.

  4. Source mechanisms and near-source wave propagation from broadband seismograms

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    J. Perrot


    Full Text Available Recording seismic events at teleseismic distances with broadband and high dynamic range instruments provides new high-quality data that allow us to interpret in more detail the complexity of seismic rupture as well as the heterogeneous structure of the medium surrounding the source where waves are initially propagating. Wave propagation analysis is performed by ray tracing in a local cartesian coordinate system near the source and in a global spherical coordinate system when waves enter the mantle. Seismograms are constructed at each station for a propagation in a 2.5-D medium. Many phases can be included and separately analyzed; this is one of the major advantages of ray tracing compared to other wave propagation techniques. We have studied four earthquakes, the 1988 Spitak Armenia Earthquake (Ms = 6.9, the 1990 Iran earthquake (Ms = 7.7, the 1990 romanian earthquake (Ms = 5.8 and the 1992 Erzincan, Turkey earthquake (Ms = 6.8. These earthquakes exhibit in different ways the complexity of the rupture and the signature of the medium surrounding the source. The use of velocity seismograms, the time derivative of displacement, increases the difficulty of the fit between synthetic seismograms and real seismograms but provides clear evidence for a need of careful time delay estimations of the different converted phases. We find that understanding of the seismic rupture as well as the influence of the medium surrounding the source for teleseismically recorded earthquakes requires a multi-stop procedure: starting with ground displacement seismograms, one is able to give a first description of the rupture as well as of the first-order influence of the medium. Then, considering the ground velocity seismograms makes the fit more difficult to obtain but increases our sensitivity to the rupture process and early converted phases. With increasing number of worldwide broadband stations, a complex rupture description is possible independently of field

  5. Ruptured venous aneurysm of cervicomedullary junction

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    Ashish Aggarwal


    Full Text Available Background: Ruptured venous aneurysm is often seen with arterio-venous malformation (AVM or developmental venous anomaly (DVA. However, isolated venous aneurysm is unusual. Case Description: We present a case of ruptured venous aneurysm that presented with subarachnoid hemorrhage (SAH and intraventricular hemorrhage (IVH. Digital substraction angiography (DSA revealed a saccular contrast filling pouch in the left lateral aspect of cervicomedullary junction (CMJ. Endovascular intervention was not a viable option. During surgery, a saccular pliable structure approx. 1.5 Χ 1 cm was found in the subarachnoid space that was clipped and excised. There were no arterial feeders, no evidence of surrounding AVM, and no dilated perimedullary vein. Conclusion: This is perhaps the first reported case of ruptured venous aneurysm (without associated AVM of CMJ, which was successfully managed surgically. The possible etiologies remain an unnoticed head trauma or a congenital vessel wall abnormality. Surgically clipping and excision remains the treatment of choice for such lesion.

  6. The Identity Process in Times of Ruptures

    DEFF Research Database (Denmark)

    Awad, Sarah H.


    revolution, at which time Egypt has witnessed major social and political changes. The aim is to understand the identity process of individuals as they develop and adapt through changing social contexts and how they create alternative social relations as they engage in prefigurative politics. The findings......This is a longitudinal study of the identity process through times of dramatic social change. Using a narrative psychological approach this research follows the life stories of five Egyptian bloggers as they write their stories on online blogs over the course of the three years following the 2011...... shed light on how ruptures trigger a process of reflexivity, adaptive learning, and sense-making that facilitates coping and the reconstruction of a positive identity after ruptures. It also suggests that the narration of the experience of rupture through storytelling creates a heightened sense...

  7. Right ventricular hydatid cyst ruptured to pericardium

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    Feridoun Sabzi


    Full Text Available Cardiac hydatidosis is rare presentation of body hydatidosis. Incidence of cardiac involvements range from 5% to 5% of patients with hydatid disease. Most common site of hydatid cyst in heart is interventricular septum and left ventricular free wall. Right ventricular free wall involvement by cyst that ruptured to pericardial cavity is very rare presentation of hydatid cyst. Cardiac involvement may have serious consequences such as rupture to blood steam or pericardial cavity. Both the disease and its surgical treatment carry a high complication rate, including rupture leading to cardiac tamponade, anaphylaxis and also death. In the present report, a 43-year-old man with constrictive pericarditis secondary to a pericardial hydatid cyst is described.

  8. The Identity Process in Times of Ruptures

    DEFF Research Database (Denmark)

    Awad, Sarah H.


    This is a longitudinal study of the identity process through times of dramatic social change. Using a narrative psychological approach this research follows the life stories of five Egyptian bloggers as they write their stories on online blogs over the course of the three years following the 2011...... revolution, at which time Egypt has witnessed major social and political changes. The aim is to understand the identity process of individuals as they develop and adapt through changing social contexts and how they create alternative social relations as they engage in prefigurative politics. The findings...... shed light on how ruptures trigger a process of reflexivity, adaptive learning, and sense-making that facilitates coping and the reconstruction of a positive identity after ruptures. It also suggests that the narration of the experience of rupture through storytelling creates a heightened sense...

  9. Creep rupture behavior of unidirectional advanced composites (United States)

    Yeow, Y. T.


    A 'material modeling' methodology for predicting the creep rupture behavior of unidirectional advanced composites is proposed. In this approach the parameters (obtained from short-term tests) required to make the predictions are the three principal creep compliance master curves and their corresponding quasi-static strengths tested at room temperature (22 C). Using these parameters in conjunction with a failure criterion, creep rupture envelopes can be generated for any combination of in-plane loading conditions and ambient temperature. The analysis was validated experimentally for one composite system, the T300/934 graphite-epoxy system. This was done by performing short-term creep tests (to generate the principal creep compliance master curves with the time-temperature superposition principle) and relatively long-term creep rupture tensile tests of off-axis specimens at 180 C. Good to reasonable agreement between experimental and analytical results is observed.

  10. Rupture of pectoralis major muscle: review article

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    Guity MR


    Full Text Available "nBackground: Rupture of pectoralis major muscle is a very rare and often athletic injury. These days in our country this injury occurs more frequently. This could be due to increase in professional participation of amateur people in different types of sport, like body building and weight-lifting (especially bench-pressing without adequate preparation, training and taking necessary precautions. In this article, we have tried to review several aspects of complex anatomy of pectoralis major muscle, epidemiology, mechanism, clinical presentations, imaging modalities, surgical indications and techniques of its rupture. Complex and especial anatomy of pectoralis major muscle, in its humeral insertion particularly, have a major role of its vulnerability to sudden and eccentric contraction as the main mechanism of rupture. Also, restoration of this complex anatomy seems to be important during surgical repair to have normal function of the muscle again.

  11. Linguine sign in musculoskeletal imaging: calf silicone implant rupture

    Energy Technology Data Exchange (ETDEWEB)

    Duryea, Dennis; Petscavage-Thomas, Jonelle [Milton S. Hershey Medical Center, Department of Radiology, H066, 500 University Drive, P.O. Box 850, Hershey, PA (United States); Frauenhoffer, Elizabeth E. [Milton S. Hershey Medical Center, Department of Pathology, 500 University Drive, P.O. Box 850, Hershey, PA (United States); Walker, Eric A. [Milton S. Hershey Medical Center, Department of Radiology, H066, 500 University Drive, P.O. Box 850, Hershey, PA (United States); Uniformed Services University of the Health Sciences, Department of Radiology and Nuclear Medicine, Bethesda, MD, 20814 (United States)


    Imaging findings of breast silicone implant rupture are well described in the literature. On MRI, the linguine sign indicates intracapsular rupture, while the presence of silicone particles outside the fibrous capsule indicates extracapsular rupture. The linguine sign is described as the thin, wavy hypodense wall of the implant within the hyperintense silicone on T2-weighted images indicative of rupture of the implant within the naturally formed fibrous capsule. Hyperintense T2 signal outside of the fibrous capsule is indicative of an extracapsular rupture with silicone granuloma formation. We present a rare case of a patient with a silicone calf implant rupture and discuss the MRI findings associated with this condition. (orig.)

  12. Rupture Processes of the Mw8.3 Sea of Okhotsk Earthquake and Aftershock Sequences from 3-D Back Projection Imaging (United States)

    Jian, P. R.; Hung, S. H.; Meng, L.


    On May 24, 2013, the largest deep earthquake ever recorded in history occurred on the southern tip of the Kamchatka Island, where the Pacific Plate subducts underneath the Okhotsk Plate. Previous 2D beamforming back projection (BP) of P- coda waves suggests the mainshock ruptured bilaterally along a horizontal fault plane determined by the global centroid moment tensor solution. On the other hand, the multiple point source inversion of P and SH waveforms argued that the earthquake comprises a sequence of 6 subevents not located on a single plane but actually distributed in a zone that extends 64 km horizontally and 35 km in depth. We then apply a three-dimensional MUSIC BP approach to resolve the rupture processes of the manishock and two large aftershocks (M6.7) with no a priori setup of preferential orientations of the planar rupture. The maximum pseudo-spectrum of high-frequency P wave in a sequence of time windows recorded by the densely-distributed stations from US and EU Array are used to image 3-D temporal and spatial rupture distribution. The resulting image confirms that the nearly N-S striking but two antiparallel rupture stages. The first subhorizontal rupture initially propagates toward the NNE direction, while at 18 s later it directs reversely to the SSW and concurrently shifts downward to 35 km deeper lasting for about 20 s. The rupture lengths in the first NNE-ward and second SSW-ward stage are about 30 km and 85 km; the estimated rupture velocities are 3 km/s and 4.25 km/s, respectively. Synthetic experiments are undertaken to assess the capability of the 3D MUSIC BP for the recovery of spatio-temporal rupture processes. Besides, high frequency BP images based on the EU-Array data show two M6.7 aftershocks are more likely to rupture on the vertical fault planes.

  13. Shallow-Water Propagation (United States)


    Shallow- Water Propagation William L. Siegmann Rensselaer Polytechnic Institute 110 Eighth Street Troy, New York 12180-3590 phone: (518) 276...ocean_acoustics LONG-TERM GOALS Develop methods for propagation and coherence calculations in complex shallow- water environments, determine...intensity and coherence. APPROACH (A) Develop high accuracy PE techniques for applications to shallow- water sediments, accounting for

  14. A Rare Case of Simultaneous Acute Bilateral Quadriceps Tendon Rupture and Unilateral Achilles Tendon Rupture

    Directory of Open Access Journals (Sweden)

    Wei Yee Leong


    Full Text Available Introduction: There have been multiple reported cases of bilateral quadriceps tendon ruptures (QTR in the literature. These injuries frequently associated with delayed diagnosis, which results in delayed surgical treatment. In very unusual cases, bilateral QTRs can be associated with other simultaneous tendon ruptures. Case Report: We present a rare case of bilateral QTR with a simultaneous Achilles Tendon Rupture involving a 31 years old Caucasian man who is a semi-professional body builder taking anabolic steroids. To date bilateral QTR with additional TA rupture has only been reported once in the literature and to our knowledge this is the first reported case of bilateral QTR and simultaneous TA rupture in a young, fit and healthy individual. Conclusion: The diagnosis of bilateral QTR alone can sometimes be challenging and the possibility of even further tendon injuries should be carefully assessed. A delay in diagnosis could result in delay in treatment and potentially worse outcome for the patient. Keywords: Quadriceps tendon rupture; Achilles tendon rupture; Bilateral.

  15. Rupture complexity of the M6.0 Amatrice Earthquake probed by 1D and 3D velocity models (United States)

    Tinti, E.; Scognamiglio, L.; Casarotti, E.; Magnoni, F.; Quintiliani, M.; Michelini, A.; Cocco, M.


    On 24th August 2016 a ML 6.0 earthquake occurred in the Central Apennines (Italy) between Amatrice and Norcia causing heavy damages and nearly 300 fatalities. The main shock and most of the aftershocks show NNW-SSE striking focal mechanisms in agreement with the current NE-SW extensional tectonic setting of Central Apennines. To image the rupture history of the Amatrice earthquake, we invert the ground velocity time histories obtained from 26 three components strong motion accelerometers located within 45 km from the fault, filtered between 0.02 and 0.5 Hz. The inferred slip distribution is heterogeneous and characterized by two shallow slip patches located up-dip and NW from the hypocenter. The rupture history shows a bilateral propagation and a relatively high rupture velocity (3.1 km/s), producing evident directivity effects both N-NW and SE of the hypocenter and characterizing the recorded near-source peak ground motions. The retrieved rupture model provides a good fit to observed ground velocities up to 1 Hz, corroborating the contribution of rupture directivity and slip heterogeneity to ground shaking and damage pattern. We highlight that fault dimensions and peak slip values are relatively large for a moderate-magnitude earthquake. Finally, we have performed a forward modeling of seismic wave propagation in a 3D crustal model, using the imaged rupture history as the source model, to verify the effects of topography and velocity model on the calculated ground motions, and interpret the inferred source heterogeneity.

  16. Simulating Earthquake Rupture and Off-Fault Fracture Response: Application to the Safety Assessment of the Swedish Nuclear Waste Repository

    KAUST Repository

    Falth, B.


    To assess the long-term safety of a deep repository of spent nuclear fuel, upper bound estimates of seismically induced secondary fracture shear displacements are needed. For this purpose, we analyze a model including an earthquake fault, which is surrounded by a number of smaller discontinuities representing fractures on which secondary displacements may be induced. Initial stresses are applied and a rupture is initiated at a predefined hypocenter and propagated at a specified rupture speed. During rupture we monitor shear displacements taking place on the nearby fracture planes in response to static as well as dynamic effects. As a numerical tool, we use the 3Dimensional Distinct Element Code (3DEC) because it has the capability to handle numerous discontinuities with different orientations and at different locations simultaneously. In tests performed to benchmark the capability of our method to generate and propagate seismic waves, 3DEC generates results in good agreement with results from both Stokes solution and the Compsyn code package. In a preliminary application of our method to the nuclear waste repository site at Forsmark, southern Sweden, we assume end-glacial stress conditions and rupture on a shallow, gently dipping, highly prestressed fault with low residual strength. The rupture generates nearly complete stress drop and an M-w 5.6 event on the 12 km(2) rupture area. Of the 1584 secondary fractures (150 m radius), with a wide range of orientations and locations relative to the fault, a majority move less than 5 mm. The maximum shear displacement is some tens of millimeters at 200 m fault-fracture distance.

  17. Gravid med spontan ruptur af arteria uterina

    DEFF Research Database (Denmark)

    Jònsdòttir, Fjòla; Pinborg, Anja; Wilken-Jensen, Charlotte


    Pregnant women with acute abdominal pain are a clinical challenge. We present a rare but potential life-threatening condition of a pregnant woman with acute abdominal pain. The woman was in gestational week 37 with severe abdominal pain and was admitted to the labour ward. She became haemo......-dynamic instable 24 hours after vaginal delivery, and emergency laparotomi revealed a spontaneous rupture of the right uterine artery. Spontaneous rupture of the uterine artery is rare but should be considered as a possible cause of acute abdominal pain in pregnant women....

  18. Thoracic Outlet Syndrome Following Breast Implant Rupture

    Directory of Open Access Journals (Sweden)

    Raakhi Mistry, MBChB


    Full Text Available Summary: We present a patient with bilateral breast implant rupture who developed severe locoregional silicone granulomatous lymphadenopathy. Poly Implant Prothese silicone implants had been used for bilateral breast augmentation 5 years prior. Extracapsular implant rupture and bilateral axillary lymphadenopathy indicated explantation, capsulectomy, and selective lymph node excision. Histology demonstrated silicone lymphadenopathy with no evidence of malignancy. Over the subsequent 12 months, she developed progressive locoregional lymphadenopathy involving bilateral cervical, axillary, and internal mammary groups, resulting in bilateral thoracic outlet syndrome. We report the unusual presentation, progression, and the ultimate surgical management of this patient.

  19. Thoracic outlet syndrome following breast implant rupture. (United States)

    Mistry, Raakhi; Caplash, Yugesh; Giri, Pratyush; Kearney, Daniel; Wagstaff, Marcus


    We present a patient with bilateral breast implant rupture who developed severe locoregional silicone granulomatous lymphadenopathy. Poly Implant Prothese silicone implants had been used for bilateral breast augmentation 5 years prior. Extracapsular implant rupture and bilateral axillary lymphadenopathy indicated explantation, capsulectomy, and selective lymph node excision. Histology demonstrated silicone lymphadenopathy with no evidence of malignancy. Over the subsequent 12 months, she developed progressive locoregional lymphadenopathy involving bilateral cervical, axillary, and internal mammary groups, resulting in bilateral thoracic outlet syndrome. We report the unusual presentation, progression, and the ultimate surgical management of this patient.


    Directory of Open Access Journals (Sweden)

    Pietro Zedde


    Full Text Available Achilles tendon rupture is currently one of the most frequent injuries in athletes. Such rupture may be caused by a sudden dorsiflexion of the ankle, pushing off with the weight bearing forefoot while extending the knee or violent dorsiflexion of a plantar flexed foot. The treatment goal consists of restoring the normal tendon length and tension, as well as the function and strength of the gastrocnemius-soleus complex. The biological repair process can be enhanced in all stages of recovery with the use of PRP (Platelet Rich Plasma without any side effects.

  1. Rupture of the plantar fascia in athletes. (United States)

    Leach, R; Jones, R; Silva, T


    Symptoms resembling those of plantar fasciitis were seen in six athletes who were thought to have a partial rupture of the plantar fascia. Treatment, which included the use of crutches, anti-inflammatory agents, strapping of the arch, and ice packs, was successful in all but one patient who had a painful mass in the area of the previous rupture. After surgical excision of the painful mass and release of the fascia, he recovered. Five of the six athletes had been previously treated with repeated local injections of steroid.


    Directory of Open Access Journals (Sweden)

    Miroslav Kezunović


    Full Text Available One of the most important goals of the treatment of sports injuries is athletes’ early return to normal sporting activities. Time when the athletes will return to normal sporting activities, after Achilles tendon acute rupture, depends on the level of sports involvement. Average time of return to sport is usually between 5-6 months after rupture. Patients, who are treated using postoperative functional cast, can expect an average return to their sport a month earlier than those who after surgery used solid cast immobilization. The most important signs that indicate possible slow rehabilitation process are the pain and swelling after activity and late recovery of the tissue.

  3. Mycotic aneurysm rupture of the descending aorta

    Energy Technology Data Exchange (ETDEWEB)

    Gufler, H.; Buitrago-Tellez, C.H.; Nesbitt, E.; Hauenstein, K.H. [Department of Radiology, Albert-Ludwigs-Universitaet, Freiburg (Germany)


    A 69-year-old diabetic male with salmonella bacteremia developed hypovolemic shock and swelling of the neck. A CT examination revealed massive mediastinal hemorrhage extending into the neck soft tissues caused by false aneurysm rupture of the descending thoracic aorta. Aortography showed continuous extravasation from a large leak at the medial side of the descending thoracic aorta. Although surgical intervention was immediately performed, the patient died 3 weeks later from multiple-organ failure. In this report, CT and angiographic findings of mycotic aneurysm rupture are presented and a review is given. (orig.) With 2 figs., 11 refs.

  4. Circumferential gap propagation in an anisotropic elastic bacterial sacculus

    CERN Document Server

    Taneja, Swadhin; Rutenberg, Andrew D


    We have modelled stress concentration around small gaps in anisotropic elastic sheets, corresponding to the peptidoglycan sacculus of bacterial cells, under loading corresponding to the effects of turgor pressure in rod-shaped bacteria. We find that under normal conditions the stress concentration is insufficient to mechanically rupture bacteria, even for gaps up to a micron in length. We then explored the effects of stress-dependent smart-autolysins, as hypothesised by Arthur L Koch [Advances in Microbial Physiology 24, 301 (1983); Research in Microbiology 141, 529 (1990)]. We show that the measured anisotropic elasticity of the PG sacculus can lead to stable circumferential propagation of small gaps in the sacculus. This is consistent with the recent observation of circumferential propagation of PG-associated MreB patches in rod-shaped bacteria. We also find a bistable regime of both circumferential and axial gap propagation, which agrees with behavior reported in cytoskeletal mutants of B. subtilis. We con...

  5. The Road Less Traveled: Why the 2002 Denali Rupture Took the Totschunda Exit (United States)

    Schwartz, D. P.; Haeussler, P. J.; Seitz, G. G.; Dawson, T. E.


    A particularly interesting aspect of the 2002 M7.9 Denali fault earthquake was the propagation of the rupture from the central Denali fault (CDF) onto the Totschunda fault (TF). New LiDAR data and paleoseismic data provide the basis to more clearly map the structure of the intersection and evaluate controls of fault branching. LiDAR data reveal the CDF-TF intersection is structurally simple. At km 225.7 east of the 2002 epicenter the CDF rupture (trending 125°) bends slightly (5°) south and an unruptured fault trace extends eastward from it. Both faults parallel each other for 1.5 km through a 170 m-wide right bend, with the surface traces 40-90 m apart. At km 227.2 the two faults are 65 m apart. Here, the 2002 rupture, which is now the TF, diverges southeast (138°); the unruptured fault, which is the eastern Denali fault (EDF), continues eastward with a trend of 121°. There is no step or jump; one fault simply becomes two. 2D analyses and numerical simulations (Kame et al, 2003) suggest three key parameters influence branching: orientation of the principal maximum stress with regard to the main fault, rupture velocity near the branch point, and orientation of the branch relative to the main fault. Varying these, Bhat et al (2004) find that for most simulations the CDF rupture continues on the TF. Oglesby et al (2004) performed inverse kinematic and 3D forward dynamic modeling and conclude that a combination of a more favorable orientation to the local stress field and dynamic changes in shear and normal stress favored rupture onto the TF. In contrast, we use paleoseismic data to propose that the state of stress at the intersection, as defined by the accumulated strain on each fault (estimated from slip rate and elapsed time since the most recent event), is the primary control of the branching direction and whether propagation beyond the branch point occurs at all. The EDF slip rate is 8.4 (± 2.0) mm/yr; the TF slip rate is 6 (±1.1) mm/yr (Matmon et al, 2006

  6. Kirchhoff Reconstruction for Real-Time Fault Rupture Determination (United States)

    Baker, T.; Granat, R.; Clayton, R.; Shelton, K.


    We present a method for locating earthquake ruptures in real time using Kirchhoff reconstruction. The method determines not the hypocenter, but the actual shape and dimensions of the earthquake fault rupture. The real time capability to generate a detailed rupture map will provide emergency response teams with information about the region of damage and thereby allow them to optimize the distribution of resources and personnel. In addition, it will allow for rapid deployment of instruments focused on collecting observations of post-seismic activity. Computational time does not scale with event magnitude, so the Kirchhoff reconstruction method can accurately handle earthquakes of any magnitude. The Kirchhoff method uses measurements of ground motion from an array of sensors. A grid is generated covering the area of interest. The ground motion at each grid coordinate is summed based on the measurements at contributing sensor locations and the wave propagation time and distance from these locations. Correlation of the measurements occurs at the grid points that correspond to the trace of the event. Our implementation handles arbitrary grid densities and configurations, allowing high resolution over areas of interest. The method is furthermore independent of any particular sensor geometry. The software is capable of integrating the most detailed rheology or wave velocity model available, in order to achieve greater accuracy. Preliminary results are presented for tests of the method on both simulated and historic data. We demonstrate the robustness of the method with respect to signal noise, and show the level of detail and precision available for example historic events. We intend for the software to be integrated into the TriNet earthquake information system. This will enhance the service TriNet provides to emergency response teams and scientists and researchers assessing the status of seismic activity. The Kirchhoff method can contribute to development of a

  7. Rupture complexity of the three main shocks of the 2016 Central Italy seismic sequence (United States)

    Tinti, Elisa; Scognamiglio, Laura; Magnoni, Federica; Casarotti, Emanuele; Michelini, Alberto; Cocco, Massimo


    The 2016 Central Italy seismic sequence, started on August 24th, ruptured an almost 60 km long segmented fault system between Amatrice, Norcia and Pieve Torina and is characterized by three main events and more than 45.000 aftershocks. A key feature of the studied sequence is the temporal distribution of the seismic moment release: the largest magnitude event (Mw 6.5, 30th October) occurred two months after the first main shock (Mw 6.0, 24th August) and only four days after the second main event (Mw 5.9, 26th October). All the three main events and most of the aftershocks show NNW-SSE striking focal mechanisms in agreement with the current NE-SW extensional tectonic setting of Central Apennines. To image the rupture history of the three main events of the sequence, we invert the ground velocity time histories obtained from three-component strong motion accelerometers located within 45 km from the faults, filtered between 0.02-0.5 Hz. To improve the fit between data and synthetics we also test complex source geometries and assume rupture segmentation on a number of distinct fault planes. Overall, the retrieved rupture histories display heterogeneous slip distributions with high peak slip values and directivity effects. These features can explain the localized high values of the peak ground motions. Finally, to test the inferred source heterogeneity and directivity, and verify how the topography and geological constraints affect the calculated ground motion, we propagate the retrieved kinematic rupture models within a 3D forward simulation and compare the results to the available observations.

  8. Spontaneous Uterine Rupture during Pregnancy: Case Report and ...

    African Journals Online (AJOL)

    After ultrasound scan, uterine rupture was diagnosed and an emergency .... Uterine rupture in multiparity occurs usually during labour. We think that our patient may have had uterine scar from ... abdominal pains and signs of shock, at which.

  9. Source rupture process of the 2011 Fukushima-ken Hamadori earthquake: how did the two subparallel faults rupture? (United States)

    Tanaka, Miho; Asano, Kimiyuki; Iwata, Tomotaka; Kubo, Hisahiko


    The 2011 Fukushima-ken Hamadori earthquake (MW 6.6) occurred about a month after the 2011 Great Tohoku earthquake (MW 9.0), and it is thought to have been induced by the 2011 Tohoku earthquake. After the 2011 Hamadori earthquake, two subparallel faults (the Itozawa and Yunodake faults) were identified by field surveys. The hypocenter was located nearby the Itozawa fault, and it is probable that the Itozawa fault ruptured before the Yunodake fault rupture. Here, we estimated the source rupture process of the 2011 Hamadori earthquake using a model with two subparallel faults based on strong motion data. The rupture starting point and rupture delay time of the Yunodake fault were determined based on Akaike's Bayesian Information Criterion (ABIC). The results show that the Yunodake fault started to rupture from the northern deep point 4.5 s after the Itozawa fault started to rupture. The estimated slip distribution in the shallow part is consistent with the surface slip distribution identified by field surveys. Time-dependent Coulomb failure function changes (ΔCFF) were calculated using the stress change from the Itozawa fault rupture in order to evaluate the effect of the rupture on the Yunodake fault. The ΔCFF is positive at the rupture starting point of the Yunodake fault 4.5 s after the Itozawa fault started to rupture; therefore, it is concluded that during the 2011 Hamadori earthquake, the Yunodake fault rupture was triggered by the Itozawa fault rupture.

  10. Hitherto unknown shear rupture mechanism as a source of instability in intact hard rocks at highly confined compression (United States)

    Tarasov, Boris G.


    Today, frictional shear resistance along pre-existing faults is considered to be the lower limit on rock shear strength for confined conditions corresponding to the seismogenic layer. This paper introduces a recently identified shear rupture mechanism providing a paradoxical feature of hard rocks - the possibility of shear rupture propagation through the highly confined intact rock mass at shear stress levels significantly less than frictional strength. In the new mechanism, the rock failure associated with consecutive creation of small slabs (known as ‘domino-blocks') from the intact rock in the rupture tip is driven by a fan-shaped domino structure representing the rupture head. The fan-head combines such unique features as: extremely low shear resistance, self-sustaining stress intensification, and self-unbalancing conditions. Due to this the failure process caused by the mechanism is very dynamic and violent. This makes it impossible to directly observe and study the mechanism and can explain why the mechanism has not been detected before. This paper provides physical motivation for the mechanism, based upon side effects accompanying the failure process. Physical and mathematical models of the mechanism presented in the paper explain unique and paradoxical features of the mechanism. The new shear rupture mechanism allows a novel point of view for understanding the nature of spontaneous failure processes in hard rocks including earthquakes.

  11. Structural features and seismotectonic implications of coseismic surface ruptures produced by the 2016 M w 7.1 Kumamoto earthquake (United States)

    Lin, Aiming


    Field investigations and analyses of satellite images and aerial photographs reveal that the 2016 M w 7.1 (Mj 7.3) Kumamoto earthquake produced a ˜40-km surface rupture zone striking NE-SW on central Kyushu Island, Japan. Coseismic surface ruptures were characterized by shear faults, extensional cracks, and mole tracks, which mostly occurred along the pre-existing NE-SW-striking Hinagu-Futagawa fault zone in the southwest and central segments, and newly identified faults in the northeast segment. This study shows that (i) the Hinagu-Futagawa fault zone triggered the 2016 Kumamoto earthquake and controlled the spatial distribution of coseismic surface ruptures; (ii) the southwest and central segments were dominated by right-lateral strike-slip movement with a maximum in-site measured displacement of up to 2.5 m, accompanied by a minor vertical component. In contrast, the northeast segment was dominated by normal faulting with a maximum vertical offset of up to 1.75 m with a minor horizontal component that formed graben structures inside Aso caldera; (iii) coseismic rupturing initiated at the jog area between the Hinagu and Futagawa faults, then propagated northeastward into Aso caldera, where it terminated. The 2016 M w 7.1 Kumamoto earthquake therefore offers a rare opportunity to study the relationships between coseismic rupture processes and pre-existing active faults, as well as the seismotectonics of Aso volcano.

  12. Fracture energies at the rupture nucleation points of large strike-slip earthquakes on the Xianshuihe fault, southwestern China (United States)

    Xie, Yuqing; Kato, Naoyuki


    Earthquake cycles along a pure strike-slip fault were numerically simulated using a rate- and state-dependent friction law to obtain the fracture energies at the rupture nucleation points. In the model, deep aseismic slip is imposed on the fault, which generates recurrent earthquakes in the shallower velocity-weakening friction region. The fracture energy at the rupture nucleation point for each simulated earthquake was calculated using the relation between shear stress and slip, which indicates slip-weakening behavior. The simulation results show that the relation between the fracture energy at the nucleation point and other source parameters is consistent with a theoretical approach based on fracture mechanics, in that an earthquake occurs when the energy release rate at the tip of the aseismic slip zone first exceeds the fracture energy. Because the energy release rate is proportional to the square of the amount of deep aseismic slip during the interseismic period, which can be estimated from the recurrence interval of earthquakes and the deep aseismic slip rate, the fracture energies for strike-slip earthquakes can be calculated. Using this result, we estimated the fracture energies at the nucleation points of large earthquakes on selected segments of the Xianshuihe fault, southwestern China. We find that the estimated fracture energies at the rupture nucleation points are generally smaller than the values of average fracture energy for developed ruptures as estimated in previous studies, suggesting that the fracture energy tends to increase with the rupture propagation distance.

  13. Bilateral synchronous rupture of the quadriceps tendon.

    LENUS (Irish Health Repository)

    Ellanti, P


    Bilateral simultaneous rupture of the quadriceps tendon is a rare entity. They are often associated with degenerative changes of the tendons and predisposing conditions such as diabetes or excessive steroid use. They most commonly tend to occur in patients of 40 years of age or older.

  14. The electrocardiogram in traumatic right atrial rupture

    NARCIS (Netherlands)

    van Veldhuisen, DJ; van den Berg, MP


    We:report the case of a previously healthy 20-year-old man who had a traumatic rupture of the right atrium. On admission an electrocardiogram (ECG) was recorded which is highly remarkable and, retrospectively, suggestive for the diagnosis. The patient died soon after the EGG, and the diagnosis was m


    Directory of Open Access Journals (Sweden)

    N. A. Koryshkov


    Full Text Available From 1998 to 2010 32 patients (14 men, 18 women, aged 15-65 years, underwent surgical treatment for old Achilles tendon rupture. In all cases correct diagnosis was made not earlier than 1 month after injury. The importance of clinical Thompson test and sonographic examination for diagnosis of Achilles tendon rupture is underlined. For the restoration of Achilles tendon V-Y plasty was used. Surgery was performed in a period of 1 to 13 months in patients with subcutaneous Achilles tendon ruptures. Follow-up results of patients in the postoperative period ranged from 6 months to 10 years (mean follow-up 1 year 7 months. Date of observation in the postoperative period ranged from 6 months to 19 years. Marginal necrosis wound occurred in 3 (10% patients, re-rupture of the Achilles tendon to tendon suture zone - in one patient, even in one patient on day 14 became infected. Violations of the foot innervation were no detected.

  16. Plantar fascia rupture associated with corticosteroid injection. (United States)

    Sellman, J R


    A series of 37 patients, all with a presumptive diagnosis of plantar fascia rupture, is presented. All had had prior heel pain diagnosed as plantar fasciitis, and all had been treated with corticosteroid injection into the calcaneal origin of the fascia. One third described a sudden tearing episode in the heel, while the rest had a gradual change in symptoms. Most of the patients had relief of the original heel pain, which had been replaced by a variety of new foot problems, including dorsal and lateral midfoot pain, swelling, foot weakness, metatarsal pain, and metatarsal fracture. In all 37 patients, there was a palpable diminution in the tension of the plantar fascia on the involved side, and footprints often showed a flattening of the involved arch. Magnetic resonance imaging done on one patient showed attenuation of the plantar fascia. From these observations and data, the author concluded that plantar fascia rupture had occurred. Treatment following rupture included supportive shoes, orthoses, and time. The majority had resolution of their new symptoms, but this often took 6 to 12 months to occur. In the remainder, there were persisting symptoms. Corticosteroid injections, although helpful in the treatment of plantar fasciitis, appear to predispose to plantar fascia rupture.

  17. Muscle rupture associated with statin use

    NARCIS (Netherlands)

    Ekhart, C.; Jong, L.A.W.; Gross-Martirosyan, L.; Hunsel, F. van


    AIM: Statins are used in the treatment of hyperlipidaemia. They are among the most commonly prescribed drugs worldwide. Statins have been linked to musculoskeletal adverse drug reactions. However muscle rupture has not been discussed as an adverse drug reaction to statins so far. The aim of this

  18. Case report: Traumatic unilateral testicular rupture

    Directory of Open Access Journals (Sweden)

    Natasha J.G. Bauer


    Conclusion: Emergency assessment and diagnosis as well as scrotal exploration are important components of the management of acute testicular rupture. Analysis of the literature proves that timely surgical intervention is crucial; early intervention results in higher rates of preservation and avoids the need for an orchidectomy.

  19. Diagnosis and management of testicular ruptures. (United States)

    Buckley, Jill C; McAninch, Jack W


    Testicular ruptures are a common occurrence in scrotal trauma that can go undetected ifa thorough examination or scrotal ultrasonography is not performed. Timely operative exploration and reconstruction is the standard of care and leads to high testicular salvage rates with hormonal, reproductive, and cosmetic benefits for the patient.

  20. Surgical management of spontaneous ruptured hepatocellular adenoma

    Directory of Open Access Journals (Sweden)

    Marcelo Augusto Fontenelle Ribeiro Junior


    Full Text Available AIMS: Spontaneous ruptured hepatocellular adenoma (SRHA is a rare life-threatening condition that may require surgical treatment to control hemorrhaging and also stabilize the patient. We report a series of emergency surgeries performed at our institution for this condition. METHODS: We reviewed medical records and radiology files of 28 patients (from 1989 to 2006 with a proven diagnosis of hepatocellular adenoma (HA. Three (10.7% of 28 patients had spontaneous ruptured hepatocellular adenoma, two of which were associated with intrahepatic hemorrhage while one had intraperitoneal bleeding. Two patients were female and one was male. Both female patients had a background history of oral contraceptive use. Sudden abdominal pain associated with hemodynamic instability occurred in all patients who suffered from spontaneous ruptured hepatocellular adenoma. The mean age was 41.6 years old. The preoperative assessment included liver function tests, ultrasonography and computed tomography. RESULTS: The surgical approaches were as follows: right hemihepatectomy for controlling intraperitoneal bleeding, and right extended hepatectomy and non-anatomic resection of the liver for intrahepatic hemorrhage. There were no deaths, and the postoperative complications were bile leakage and wound infection (re-operation, as well as intraperitoneal abscess (re-operation and pleural effusion. CONCLUSION: Spontaneous ruptured hepatocellular adenoma may be treated by surgery for controlling hemorrhages and stabilizing the patient, and the decision to operate depends upon both the patient's condition and the expertise of the surgical team.

  1. [Simultaneous rupture of a patellar tendon and contralateral quadriceps tendon]. (United States)

    Horas, U; Ernst, S; Meyer, C; Halbsguth, A; Herbst, U


    The simultaneous bilateral rupture of the quadriceps tendon is a rare injury; only occasional reports exist about the bilateral simultaneous rupture of the patellar tendon. Degenerative changes of the tendon due to drugs or diseases lead to the rupture. We describe two cases of simultaneous rupture of the patellar and contralateral quadriceps tendons; only one patient had special risks. We report the management of therapy and the functional results using the Lysholm score and Knee Rating Scale.

  2. Gear Crack Propagation Investigation (United States)


    Reduced weight is a major design goal in aircraft power transmissions. Some gear designs incorporate thin rims to help meet this goal. Thin rims, however, may lead to bending fatigue cracks. These cracks may propagate through a gear tooth or into the gear rim. A crack that propagates through a tooth would probably not be catastrophic, and ample warning of a failure could be possible. On the other hand, a crack that propagates through the rim would be catastrophic. Such cracks could lead to disengagement of a rotor or propeller from an engine, loss of an aircraft, and fatalities. To help create and validate tools for the gear designer, the NASA Lewis Research Center performed in-house analytical and experimental studies to investigate the effect of rim thickness on gear-tooth crack propagation. Our goal was to determine whether cracks grew through gear teeth (benign failure mode) or through gear rims (catastrophic failure mode) for various rim thicknesses. In addition, we investigated the effect of rim thickness on crack propagation life. A finite-element-based computer program simulated gear-tooth crack propagation. The analysis used principles of linear elastic fracture mechanics, and quarter-point, triangular elements were used at the crack tip to represent the stress singularity. The program had an automated crack propagation option in which cracks were grown numerically via an automated remeshing scheme. Crack-tip stress-intensity factors were estimated to determine crack-propagation direction. Also, various fatigue crack growth models were used to estimate crack-propagation life. Experiments were performed in Lewis' Spur Gear Fatigue Rig to validate predicted crack propagation results. Gears with various backup ratios were tested to validate crack-path predictions. Also, test gears were installed with special crack-propagation gages in the tooth fillet region to measure bending-fatigue crack growth. From both predictions and tests, gears with backup ratios

  3. The Wheeler Propagator

    CERN Document Server

    Bollini, C G


    We study the half advanced and half retarded Wheeler Green function and its relation to Feynman propagators. First for massless equation. Then, for Klein-Gordon equations with arbitrary mass parameters; real, imaginary or complex. In all cases the Wheeler propagator lacks an on-shell free propagation. The Wheeler function has support inside the light-cone (whatever the mass). The associated vacuum is symmetric with respect to annihilation and creation operators. We show with some examples that perturbative unitarity holds, whatever the mass (real or complex). Some possible applications are discussed.

  4. A case of splenic torsion and rupture presenting as ruptured ectopic pregnancy

    Directory of Open Access Journals (Sweden)

    Somdatta Lahiri


    Full Text Available Splenic torsion with rupture of spleen is an extremely rare phenomenon. The clinical picture mimics several common conditions which are causes of acute abdomen and so it is seldom detected pre-operatively. An 18 year old female patient was admitted with an acute abdomen and shock. The provisional diagnosis was of a ruptured ectopic pregnancy. Peri-operatively we found a spontaneous rupture of the spleen following torsion along with early intrauterine pregnancy. Splenectomy was carried out and patient recovered well. Our report confirms that this rare entity can present as an acute abdomen which is very difficult to diagnose preoperatively and can masquerade as ruptured ectopic pregnancy in women of childbearing age group.

  5. Challenging Friesian horse diseases : aortic rupture and megaesophagus

    NARCIS (Netherlands)

    Ploeg, M.


    Aortic rupture is quite rare in Warmblood horses and is best known as an acute and fatal rupture of the aortic root in older breeding stallions. It has now become clear that aortic rupture, which is diagnosed around an age of 4 years, is more frequent in the Friesian breed than in others. The high p

  6. Bilateral spontaneous rupture of flexor digitorum profundus tendons.

    LENUS (Irish Health Repository)

    O'Sullivan, S T


    Spontaneous tendon rupture is an unusual condition usually associated with underlying disease processes such as rheumatoid arthritis, chronic renal failure or bony abnormalities of the hand. We report a case of spontaneous, non-concurrent bilateral rupture of flexor profundus tendons in an otherwise healthy individual. Treatment was successful and consisted of a two-stage reconstruction of the ruptured tendon.

  7. Moment tensor inversion and source rupture process of the September 27, 2003 MS=7.9 earthquake occurred in the border area of China, Russia and Mongolia

    Institute of Scientific and Technical Information of China (English)

    ZHAO Cui-ping; CHEN Zhang-li; ZHENG Si-hua; LIU Jie


    We conducted moment tensor inversion and studied source rupture process for MS=7.9 earthquake occurred in the border area of China, Russia and Mongolia on September 27 2003, by using digital teleseismic P-wave seismograms recorded by long-period seismograph stations of the global seismic network. Considering the aftershock distribution and the tectonic settings around the epicentral area, we propose that the MS=7.9 earthquake occurred on a fault plane with the strike of 127°, the dip of 79° and the rake of 171°. The rupture process inversion result of MS=7.9 earthquake shows that the total rupture duration is about 37 s, the scalar moment tensor is M0=0.97°×1020 N°m. Rupture mainly occurred on the shallow area with 110 km long and 30 km wide, the location in which the rupture initiated is not where the main rupture took place, and the area with slip greater than 0.5 m basically lies within 35 km deep middle-crust under the earth surface. The maximum static slip is 3.6 m. There are two distinct areas with slip larger than 2.0 m. We noticed that when the rupture propagated towards northwest and closed to the area around the MS=7.3 hypocenter, the slip decreased rapidly, which may indicate that the rupture process was stopped by barriers. The consistence of spatial distribution of slip on the fault plane with the distribution of aftershocks also supports that the rupture is a heterogeneous process owing to the presence of barriers.

  8. The fracture energy of ruptures driven by flash heating (United States)

    Brantut, Nicolas; Viesca, Robert C.


    We present a model for dynamic weakening of faults based on local flash heating at microscopic asperity contacts coupled to bulk heating at macroscopic scale. We estimate the fracture energy G associated with that rheology and find that for constant slip rate histories G scales with slip δ as G∝δ2 at small slip, while G∝δ1/2 at large slip. This prediction is quantitatively consistent with data from laboratory experiments conducted on dry rocks at constant slip rate. We also estimate G for crack-like ruptures propagating at constant speed and find that G∝δ2/3 in the large slip limit. Quantitative estimates of G in that regime tend to be several orders of magnitude lower than seismologically inferred values of G. We conclude that while flash heating provides a consistent explanation for the observed dynamic weakening in laboratory experiments with kinematically imposed slip, its contribution to the energy dissipation during earthquakes becomes negligible for large events when considering the elastodynamic coupling between strength and slip evolution.

  9. Mach-wave coherence in 3D media with random heterogeneities (United States)

    Vyas, Jagdish C.; Mai, P. Martin; Galis, Martin; Dunham, Eric M.; Imperatori, Walter


    We investigate Mach-waves coherence for complex super-shear ruptures embedded in 3D random media that lead to seismic scattering. We simulate Mach-wave using kinematic earthquake sources that include fault-regions over which the rupture propagates at super-shear speed. The local slip rate is modeled with the regularized Yoffe function. The medium heterogeneities are characterized by Von Karman correlation function. We consider various realizations of 3D random media from combinations of different values of correlation length (0.5 km, 2 km, 5 km), standard deviation (5%, 10%, 15%) and Hurst exponent (0.2). Simulations in a homogeneous medium serve as a reference case. The ground-motion simulations (maximum resolved frequency of 5 Hz) are conducted by solving the elasto-dynamic equations of motions using a generalized finite-difference method, assuming a vertical strike-slip fault. The seismic wavefield is sampled at numerous locations within the Mach-cone region to study the properties and evolution of the Mach-waves in scattering media. We find that the medium scattering from random heterogeneities significantly diminishes the coherence of Mach-wave in terms of both amplitude and frequencies. We observe that Mach-waves are considerably scattered at distances RJB > 20 km (and beyond) for random media with standard deviation 10%. The scattering efficiency of the medium for small Hurst exponents (H seismic scattering. We suggest that if an earthquake is recorded within 10-15 km fault perpendicular distance and has high PGA, then inversion should be carried out by allowing rupture speed variations from sub-Rayleigh to super-shear.

  10. Liquid salt environment stress-rupture testing (United States)

    Ren, Weiju; Holcomb, David E.; Muralidharan, Govindarajan; Wilson, Dane F.


    Disclosed herein are systems, devices and methods for stress-rupture testing selected materials within a high-temperature liquid salt environment. Exemplary testing systems include a load train for holding a test specimen within a heated inert gas vessel. A thermal break included in the load train can thermally insulate a load cell positioned along the load train within the inert gas vessel. The test specimen can include a cylindrical gage portion having an internal void filled with a molten salt during stress-rupture testing. The gage portion can have an inner surface area to volume ratio of greater than 20 to maximize the corrosive effect of the molten salt on the specimen material during testing. Also disclosed are methods of making a salt ingot for placement within the test specimen.

  11. [Conservative functional treatment of Achilles tendon ruptures]. (United States)

    Hüfner, T; Gaulke, R; Imrecke, J; Krettek, C; Stübig, T


    The conservative functional treatment of Achilles tendon ruptures has developed further over the last 20 years and is basically possible for 60-80% of patients. The treatment leads to success if the indications obtained by dynamic sonography are correctly interpreted (adaptation of the tendon ends up to 20 degrees plantar flexion), if the patient presents sufficient compliance and the physiotherapy is increasingly intensified depending on tendon healing. Modern ortheses allow an increased equinus position and therefore improved protection of the healing tendon. If these factors are present a relatively low re-rupture rate of only 7% can be achieved. The decisive advantage of conservative functional therapy is the avoidance of specific operative risks, such as infection and injury to the sural nerve. After removal of the orthesis the tendon should continue to be modeled using shoe insoles and raised heels.


    Directory of Open Access Journals (Sweden)

    Shergill Harbhajan K, Grover Suparna, Chhabra Ajay


    Full Text Available It is a rare occurrence for the rudimentary horn of uterus to harbour a pregnancy and the usual outcome is devastating leading to a spontaneous rupture in second trimester with the patient presenting in shock with massive intra-peritoneal haemorrhage and if appropriate management is not instituted in time it may lead to high rate of mortality. We report an unusual case of rupture rudimentary horn pregnancy who presented as a chronic ectopic with an adnexal mass and surprisingly with no sign of shock. Diagnosis is often difficult in such a situation which puts the treating gynaecologist in dilemma. High clinical suspicion supplemented with radiological findings helped clinch the diagnosis and laparotomy was performed followed by resection of the rudimentary horn to prevent future complications.

  13. Plaque rupture in humans and mice

    DEFF Research Database (Denmark)

    Schwartz, Stephen M; Galis, Zorina S; Rosenfeld, Michael E


    Despite the many studies of murine atherosclerosis, we do not yet know the relevance of the natural history of this model to the final events precipitated by plaque disruption of human atherosclerotic lesions. The literature has become particularly confused because of the common use of terms...... such as "instability", "vulnerable", "rupture", or even "thrombosis" for features of plaques in murine model systems not yet shown to rupture spontaneously and in an animal surprisingly resistant to formation of thrombi at sites of atherosclerosis. We suggest that use of conclusory terms like "vulnerable" and "stable...... that various forms of data have implicated in plaque progression. For example, formation of the fibrous cap, protease activation, and cell death in the necrotic core can be well described and have all been modeled in well-defined experiments. The relevance of such well-defined, objective, descriptive...

  14. Case report: rupture of popliteal artery aneurysm

    Directory of Open Access Journals (Sweden)

    Altino Ono Moraes


    Full Text Available An 83-year-old female patient with a history of prior endovascular treatment to repair an abdominal aortic aneurysm presented with intense pain and edema in the left leg, with hyperemia and localized temperature increase. Doppler ultrasonography revealed a voluminous aneurysm of the popliteal artery with a contained rupture, and hematoma involving the popliteal fossa and the medial and anterior surfaces of the knee causing compression of the popliteal vein. Endovascular repair was accomplished with covered stents and the rupture was confirmed. during the procedure The aneurysm was excluded and the signs and symptoms it had caused resolved completely, but during the postoperative period the patient developed sepsis of pulmonary origin and died.

  15. Spectral element analysis on the characteristics of seismic wave propagation triggered by Wenchuan M_s8.0 earthquake

    Institute of Scientific and Technical Information of China (English)


    The 2008 Wenchuan earthquake occurred in an active earthquake zone, i.e., Longmenshan tectonic zone. Seismic waves triggered by this earthquake can be used to explore the characteristics of the fault rupture process and the hierarchical structure of the Earth’s interior. We employ spectral element method incorporated with large-scale parallel computing technology, to investigate the characteristics of seismic wave propagation excited by Wenchuan earthquake. We calculate synthetic seismograms with one-point source model and three-point source model respectively. The AK135 model is employed as a prototype of our numerical global Earth model. The Earth’s ellipticity, Earth’s medium attenuation, and topography data are taken into consideration. These wave propagation processes are simulated by solving three-dimensional elastic wave governing equations. Three-dimensional visualization of our numerical results displays the profile of the seismic wave propagation. The three-point source, which is proposed from the latest investigations through field observation and reverse estimation, can better demonstrate the spatial and temporal characteristics of the source rupture process than the one-point source. We take comparison of synthetic seismograms with observational data recorded at 16 observatory stations. Primary results show that the synthetic seismograms calculated from three-point source agree well with the observations. This can further reveal that the source rupture process of Wenchuan earthquake is a multi-rupture process, which is composed by at least three or more stages of rupture processes.

  16. Achilles tendon rupture; assessment of nonoperative treatment. (United States)

    Barfod, Kristoffer Weisskirchner


    Acute Achilles tendon rupture is a frequent and potentially disabling injury. Over the past decade a change in treatment of acute Achilles tendon rupture away from operative towards non-operative treatment has taken place. However, the optimal non-operative treatment protocol remains to be clarified, particularly the role of weight-bearing during early rehabilitation. Also, there is a need for a clinically applicable and accurate measurement to detect patients in risk of developing Achilles tendon elongation. The aim of this PhD thesis was to evaluate non-operative treatment of acute Achilles tendon rupture. In study I, a cross-sectional survey was performed investigating the chosen treatment protocols across Scandinavia. In study II, the effect of immediate weight-bearing on patient reported and functional outcomes was investigated in a randomized controlled trial (RCT). In study III, the effect of immediate weight-bearing on the biomechanical properties of the plantar flexor muscle-tendon complex was investigated in an RCT. In study IV, validity, reliability and agreement of a novel ultrasound measurement of Achilles tendon length and elongation was tested. Study I found surgery to be the preferred treatment in 83% of departments in Denmark, 92% in Norway, 65% in Sweden, and 30% in Finland (p tendon complex. Study IV showed excellent intra-rater reliability (ICC 0.96, SEM 3.7 mm and MDC 10.3 mm), inter-rater reliability (ICC 0.97, SEM 3.3 mm and MDC 9.3 mm) and validity (measurement error 2%). Treatment algorithms across Scandinavia showed considerable variation, though operative treatment and controlled early weight-bearing was the preferred treatment in Denmark, Norway and Sweden. Immediate weight-bearing was found to be safe and recommendable in non-operative treatment of acute Achilles tendon rupture. The novel ultrasound measurement showed excellent reliability and acceptable validity and agreement.

  17. Spontaneous rupture of the plantar fascia. (United States)

    Ahstrom, J P


    In this study, rupture of the plantar fascia was seen in five feet, of which four had had plantar fasciitis. At the time of the injury, which is an acceleration type of motion, there is severe pain in the heel followed by the development of ecchymosis in the sole and toward the heel of the foot. With conservative symptomatic care, the acute symptoms as well as the plantar fasciitis symptoms subside, generally allowing full activity in 3 to 4 weeks.

  18. Spontaneous bladder rupture in acute alcohol intoxication

    Directory of Open Access Journals (Sweden)

    Bahjat Barakat


    Full Text Available Spontaneous bladder rupture is a rare condition that can be followed by an acute alcohol intoxication and can be associated with significant morbidity and mortality. We report a case diagnosed in a alcoholic young male who was admitted to our emergency room for epigastric pain. The case demonstrates the difficulties with diagnosis and the need for physicians who work in an emergency room to be aware of this condition.

  19. Pneumatic Rupture of Rectosigmoid; a Case Report


    Mohammad Montazeri; Bahman Farhangi; Mahmood Montazeri


    Pneumatic rectosigmoid rapture is usually occurred following the inappropriate fun by direct entering a high volume of the air through the pneumatic device to the anus. Such an event was reported for the first time in 1904 by Stone. Diagnosis and treatment of such injuries are often delayed because of some social limitations and preventing the patient form explaining the event. Colon sigmoid rupture and pneumoperitoneum is one of the most dangerous and life treating complications of entering ...

  20. Rupture history of the 1997 Cariaco, Venezuela, earthquake from teleseismic P waves (United States)

    Mendoza, C.


    A two-step finite-fault waveform inversion scheme is applied to the broadband teleseismic P waves recorded for the strike-slip, Cariaco, Venezuela, earthquake of 9 July 1997 to recover the distribution of mainshock slip. The earthquake is first analyzed using a long narrow fault with a maximum rise time of 20 sec. This line-source analysis indicates that slip propagated to the west with a constant rupture velocity and a relatively short rise time. The results are then used to constrain a second inversion of the P waveforms using a 60-km by 20-km two-dimensional fault. The rupture shows a zone of large slip (1.3-m peak) near the hypocenter and a second, broader source extending updip and to the west at depths shallower than 5 km. The second source has a peak slip of 2.1 meters and accounts for most of the moment of 1.1 × 1026 dyne-cm (6.6 Mww) estimated from the P waves. The inferred rupture pattern is consistent with macroseismic effects observed in the epicentral area.

  1. Uncertainty analysis for probabilistic steam generators tube rupture in LBB applications

    Energy Technology Data Exchange (ETDEWEB)

    Durbec, V.; Pitner, P.; Pages, D. [Electricite de France, 78 - Chatou (France). Research and Development Div.; Riffard, T. [Electricite de France, 69 - Villeurbanne (France). Engineering and Construction Div.; Flesch, B. [Electricite de France, 92 - Paris la Defense (France). Generation and Transmission Div.


    Steam Generators (SG) of Pressurized Water Reactors have experienced world wide various types of tube degradations, mainly from stress corrosion cracking; because of this damage, primary-secondary leakage or tube rupture can occur. Safety against the risk of tube rupture is achieved through a combination of periodic in-service inspections (eddy current testing), surveillance of leaks during operation (leak before break concept) and tube plugging. In order to optimize the tube bundle SG maintenance, Electricite de France has developed a specific software named COMPROMIS. The model, based on probabilistic fracture mechanics makes it possible to quantify the influence of in service inspections and maintenance work on the risk of a SG Tube Rupture (SGTR), taking all significant parameters into account as random variables (initial defect size distribution, reliability of non-destructive examinations, crack initiation and propagation, critical sizes, leak before risk of break, etc...). This paper focuses on the leak rate calculation module and presents a sensitivity study of the influence of the leak before break on the conditional failure probability. (author) 8 refs.

  2. Radiological evaluation of sinus valsalva rupture

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yul; Park, Jae Hyung; Yeon, Kyung Mo; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)


    We obtained the following results by reviewing the radiographic findings of 15 cases of Sinus valsalva rupture who were diagnosed surgically at Seoul National University Hospital since 1979. 1. Among distribution was from 15 years to 40 years with the mean age of 24 years. Among the 15 cases, 9 cases were male and 7 were female. 2. Ruptured sinus is right coronary sinus projecting to right ventricle in all 15 cases. Combined diseases are ventricular septal defect in 12 cases, Aortic Valvular heart disease in 4 cases, and narrowing of right ventricular outflow tract in 2 cases, and aneurysmal dilatation of right pulmonary artery in 1 cases. 3. Chest X-ray findings were that of left to right shunt, i.e, cardiomegaly, increased pulmonary vascularity but were normal in 3 cases. 4. Aortography showed sequential leakage of dye from right coronary sinus to right ventricle and finally to pulmonary artery in 9 cases, and in 9 cases of them the leakage is directly to right ventricular outflow tract without filling of sinus portion of the ventricle., i.e., type I. 5. The leakage was well shown in left ventricular diastolic phase and not shown in systolic phase. 6. Ventricular septal defects were not detected definitely in spite of taking left ventriculography. 7. Cine angiography is essential for detecting accurate site, degree and direction of sinus valsalva rupture and other associated cardiac abnormality.

  3. Endovascular treatment for ruptured basilar apex aneurysm

    Directory of Open Access Journals (Sweden)

    Sheng LI


    Full Text Available Objective The present study aims to prove the effectiveness and safety of endovascular interventional therapy for ruptured basilar apex aneurysm.Methods The imaging data,methods of endovascular treatment,and clinical results of 12 patients suffering from ruptured basilar apex aneurysms from January 2001 to December 2009 were retrospectively analyzed.The 12 patients were composed of 5 males and 7 females,and their ages ranged from 21 years to 58 years.Results Nine patients suffered from narrow-necked aneurysms,which were directly embolized,and the other three suffered from wide-necked aneurysms,which were embolized using a microstent.Eight aneurysms were completely embolized,and the other four were partly embolized.No rebleeding occurred within the follow-up period of 12 months to 36 months,and all patients recovered well without neurological defects.Conclusions Therefore,endovascular treatment for ruptured basilar apex aneurysm is a semi-invasive,safe,and effective method.

  4. Isolated unilateral rupture of the alar ligament. (United States)

    Wong, Sui-To; Ernest, Kimberly; Fan, Grace; Zovickian, John; Pang, Dachling


    Only 6 cases of isolated unilateral rupture of the alar ligament have been previously reported. The authors report a new case and review the literature, morbid anatomy, and pathogenesis of this rare injury. The patient in their case, a 9-year-old girl, fell head first from a height of 5 feet off the ground. She presented with neck pain, a leftward head tilt, and severe limitation of right rotation, extension, and right lateral flexion of the neck. Plain radiographs and CT revealed no fracture but a shift of the dens toward the right lateral mass of C-1. Magnetic resonance imaging of the cervical spine showed signal hyperintensity within the left dens-atlas space on both T1- and T2-weighted sequences and interruption of the expected dark signal representing the left alar ligament, suggestive of its rupture. After 12 weeks of immobilization in a Guilford brace, MRI showed lessened dens deviation, and the patient attained full and painless neck motion. Including the patient in this case, the 7 patients with this injury were between 5 and 21 years old, sustained the injury in traffic accidents or falls, presented with marked neck pain, and were treated with external immobilization. All patients had good clinical outcome. The mechanism of injury is hyperflexion with rotation. Isolated unilateral alar ligament rupture is a diagnosis made by excluding associated fracture, dislocation, or disruption of other major ligamentous structures in the craniovertebral junction. CT and MRI are essential in establishing the diagnosis. External immobilization is adequate treatment.

  5. Rupture dynamics along bimaterial interfaces: a parametric study of the shear-normal traction coupling (United States)

    Scala, Antonio; Festa, Gaetano; Vilotte, Jean-Pierre


    Earthquake ruptures often develop along faults separating materials with dissimilar elastic properties. Due to the broken symmetry, the propagation of the rupture along the bimaterial interface is driven by the coupling between interfacial sliding and normal traction perturbations. We numerically investigate in-plane rupture growth along a planar interface, under slip weakening friction, separating two dissimilar isotropic linearly elastic half-spaces, and we perform a parametric study of the classical Prakash-Clifton regularisation, for different material contrasts. In particular the mesh-dependence and the regularisation-dependence of the numerical solutions are analysed in this parameter space. When the regularisation involves a slip-rate dependent relaxation time, a characteristic sliding distance is identified below which numerical solutions no longer depend on the regularisation parameter, i.e. they are physically well-posed solutions. Such regularisation provides an adaptive high-frequency filter of the slip-induced normal traction perturbations, following the dynamic shrinking of the dissipation zone during the acceleration phase. In contrast, a regularisation involving a constant relaxation time leads to numerical solutions that always depend on the regularisation parameter since it fails in adapting to the shrinking of the process zone. Dynamic regularisation is further investigated using a non-local regularisation based on a relaxation time that depends on the dynamic length of the dissipation zone. Such reformulation is shown to provide similar results as the dynamic time scale regularisation proposed by Prakash-Clifton when the slip rate is replaced by the maximum slip rate along the sliding interface. This leads to the identification of a dissipative length scale associated with the coupling between interfacial sliding and normal traction perturbations, together with a scaling law between the maximum slip rate and the dynamic size of the process zone

  6. Simultaneous reconstruction of quadriceps tendon rupture after TKA and neglected Achilles tendon rupture. (United States)

    Lee, Yong Seuk; Min, Byoung-Hyun; Han, Kyeong-Jin; Cho, Jae Ho; Han, Seung Hwan; Lee, Doo-Hyung; Oh, Kyung Soo


    We report a case of simultaneous reconstruction of a quadriceps tendon rupture after total knee arthroplasty (TKA) and neglected Achilles tendon rupture, which occurred before TKA with an ipsilateral hamstring autograft. A 64-year-old woman presented with persistent right knee pain. She also had right heel pain and had received multiple steroid injections at the knee joint and heel. On examination, she showed osteoarthritis in the medial and lateral compartments of the knee joint and an Achilles tendon rupture in the ipsilateral limb. There was skin dimpling and the proximal portion of tendon was migrated. We performed TKA, and the postoperative course was satisfactory. She returned 3 months postoperatively, however, with skin dimpling around the suprapatellar area and weakness of knee extension. Her ankle symptoms were also aggravated because she could not use the knee joint freely. We performed simultaneous reconstruction of the quadriceps tendon and the Achilles tendon using an ipsilateral hamstring autograft.Hamstring autograft offers a good alternative treatment option for rupture repair, particularly with concommitant ruptures of multiple sites when primary repair is not possible or the viability of repaired tissue is poor.

  7. Hierarchical Affinity Propagation

    CERN Document Server

    Givoni, Inmar; Frey, Brendan J


    Affinity propagation is an exemplar-based clustering algorithm that finds a set of data-points that best exemplify the data, and associates each datapoint with one exemplar. We extend affinity propagation in a principled way to solve the hierarchical clustering problem, which arises in a variety of domains including biology, sensor networks and decision making in operational research. We derive an inference algorithm that operates by propagating information up and down the hierarchy, and is efficient despite the high-order potentials required for the graphical model formulation. We demonstrate that our method outperforms greedy techniques that cluster one layer at a time. We show that on an artificial dataset designed to mimic the HIV-strain mutation dynamics, our method outperforms related methods. For real HIV sequences, where the ground truth is not available, we show our method achieves better results, in terms of the underlying objective function, and show the results correspond meaningfully to geographi...


    Directory of Open Access Journals (Sweden)

    F. Nili AA. Shams Ansari


    Full Text Available Premature rupture of membranes (PROM is one of the most common complications of pregnancy that has a major impact on neonatal outcomes. With respect to racial, nutritional and cultural differences between developed and developing countries, this study was conducted to detect the prevalence of neonatal complications following PROM and the role of the duration of rupture of membranes in producing morbidities and mortalities in these neonates in our hospital. Among 2357 pregnant women, we found 163 (6.91% cases of premature rupture of the fetal membranes in Tehran Vali-e-Asr Hospital during April 2001 to April 2002. Route of delivery was cesarean section in 65.6% of women. Urinary tract infection occured in 1.8%, maternal leukocytosis and fever in 20.2% and 5.5%, chorioamnionitis in 6.1%, fetal tachycardia in 1.2% and olygohydramnios in 4.9%. Gestational age in 138 (86% of neonates was less than 37 completed weeks. Thirty five infants (21.47% had respiratory distress syndrome and 33 (20.245% had clinical sepsis. Pneumonia in 6 (3.7% and skeletal deformity in 7 (4.294% were seen. Rupture of membrane of more than 24 hours duration occurred in 71 (43.6% of the patients. Comparison of morbidities between two groups of neonates and their mothers according to the duration of PROM (less and more than 24 hours showed significant differences in NICU admission, olygohydramnios, maternal fever, leukocytosis and chorioamnionitis rates (p24 hr of PROM with an odds ratio of 2.68 and 2.73, respectively. Positive blood and eye cultures were detected in 16 cases during 72 hours of age. Staphylococcus species, klebsiella, E.coli and streptococcus were the predominant organisms among positive blood cultures. Mortality was seen in 18 (11% of neonates because of respiratory failure, disseminated intravascular coagulation, septic shock, and a single case of congenital toxoplasmosis. In this study, the prevalence of prematurity, sepsis and prolonged rupture of membrane

  9. Propagation of waves

    CERN Document Server

    David, P


    Propagation of Waves focuses on the wave propagation around the earth, which is influenced by its curvature, surface irregularities, and by passage through atmospheric layers that may be refracting, absorbing, or ionized. This book begins by outlining the behavior of waves in the various media and at their interfaces, which simplifies the basic phenomena, such as absorption, refraction, reflection, and interference. Applications to the case of the terrestrial sphere are also discussed as a natural generalization. Following the deliberation on the diffraction of the "ground? wave around the ear

  10. Surface Rupture of the 2005 Kashmir, Pakistan, Earthquake and its Active Tectonic Implications (United States)

    Kaneda, H.; Nakata, T.; Tsutsumi, H.; Kondo, H.; Sugito, N.; Awata, Y.; Akhtar, S. S.; Majid, A.; Khattak, W.; Awan, A. A.; Yeats, R. S.


    The 8th October 2005 Kashmir earthquake of Mw 7.6 struck the westernmost area of the Indian-Eurasian collision zone, resulting in the worst earthquake disaster ever recorded along the frontal Himalaya. Although none of the historical Himalayan earthquakes is reported to have produced primary surface rupture, our field mapping reveals that the 2005 earthquake accompanied a NW-trending ~70-km-long distinctive surface rupture with maximum and mean vertical separations of ~7 m and ~3 m, respectively. Typical surface expression of faulting is a NE-side-up fault scarp or warp with surface shortening features at its base and tension cracks on its crest. Bulging and back-tilting are also observed on the upthrown side at many places. The surface rupture is subdivided into three geometrical segments separated by small steps. Location of the hypocenter suggests that the rupture was initiated at a deep portion of the northern-central segment boundary and bilaterally propagated to eventually break three segments. Mapped surface rupture trace clearly shows that neither the Himalayan Frontal Thrust (HFT) nor the Main Boundary Thrust (MBT) is responsible for the earthquake, but a geomorphologically-evident active fault within the Sub-Himalaya, the Balakot-Garhi fault, is a causative fault, although a part of the Balakot-Garhi fault appears to coincide with the surface trace of the MBT. Cumulative vertical separation of the most extensively recognized fluvial terrace surface is 7-8 times larger than the 2005 separation, implying occurrence of 7-8 similar earthquakes after the surface abandonment. If this deeply-incised fill surface is related to sediment yield increase due to the last major glaciation around 20 ka, the rupture interval and vertical slip rate of the Balakot-Garhi fault are estimated to be on the order of ~3000 years and ~1 mm/yr, respectively. By using the seismologically determined fault dip of ~30 degrees, horizontal shortening rate across the fault is then

  11. Distance and Azimuthal Dependence of Ground‐Motion Variability for Unilateral Strike‐Slip Ruptures

    KAUST Repository

    Vyas, Jagdish Chandra


    We investigate near‐field ground‐motion variability by computing the seismic wavefield for five kinematic unilateral‐rupture models of the 1992 Mw 7.3 Landers earthquake, eight simplified unilateral‐rupture models based on the Landers event, and a large Mw 7.8 ShakeOut scenario. We include the geometrical fault complexity and consider different 1D velocity–density profiles for the Landers simulations and a 3D heterogeneous Earth structure for the ShakeOut scenario. For the Landers earthquake, the computed waveforms are validated using strong‐motion recordings. We analyze the simulated ground‐motion data set in terms of distance and azimuth dependence of peak ground velocity (PGV). Our simulations reveal that intraevent ground‐motion variability Graphic is higher in close distances to the fault (<20  km) and decreases with increasing distance following a power law. This finding is in stark contrast to constant sigma‐values used in empirical ground‐motion prediction equations. The physical explanation of a large near‐field Graphic is the presence of strong directivity and rupture complexity. High values of Graphic occur in the rupture‐propagation direction, but small values occur in the direction perpendicular to it. We observe that the power‐law decay of Graphic is primarily controlled by slip heterogeneity. In addition, Graphic, as function of azimuth, is sensitive to variations in both rupture speed and slip heterogeneity. The azimuth dependence of the ground‐motion mean μln(PGV) is well described by a Cauchy–Lorentz function that provides a novel empirical quantification to model the spatial dependency of ground motion. Online Material: Figures of slip distributions, residuals to ground‐motion prediction equations (GMPEs), distance and azimuthal dependence, and directivity predictor of ground‐motion variability for different source models.

  12. DROMO propagator revisited (United States)

    Urrutxua, Hodei; Sanjurjo-Rivo, Manuel; Peláez, Jesús


    In the year 2000 an in-house orbital propagator called DROMO (Peláez et al. in Celest Mech Dyn Astron 97:131-150, 2007. doi: 10.1007/s10569-006-9056-3) was developed by the Space Dynamics Group of the Technical University of Madrid, based in a set of redundant variables including Euler-Rodrigues parameters. An original deduction of the DROMO propagator is carried out, underlining its close relation with the ideal frame concept introduced by Hansen (Abh der Math-Phys Cl der Kon Sachs Ges der Wissensch 5:41-218, 1857). Based on the very same concept, Deprit (J Res Natl Bur Stand Sect B Math Sci 79B(1-2):1-15, 1975) proposed a formulation for orbit propagation. In this paper, similarities and differences with the theory carried out by Deprit are analyzed. Simultaneously, some improvements are introduced in the formulation, that lead to a more synthetic and better performing propagator. Also, the long-term effect of the oblateness of the primary is studied in terms of DROMO variables, and new numerical results are presented to evaluate the performance of the method.

  13. Shallow Water Propagation (United States)


    response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and...these modes decay much more slowly than leaky modes as they propagate. The initial focus is on modal phase and group velocity formulas, obtained from...acoustic quantities such as transmission loss and scintillation index. (C) Both physical understanding and reasonable estimates of

  14. New constraints on the rupture process of the 1999 August 17 Izmit earthquake deduced from estimates of stress glut rate moments (United States)

    Clévédé, E.; Bouin, M.-P.; Bukchin, B.; Mostinskiy, A.; Patau, G.


    This paper illustrates the use of integral estimates given by the stress glut rate moments of total degree 2 for constraining the rupture scenario of a large earthquake in the particular case of the 1999 Izmit mainshock. We determine the integral estimates of the geometry, source duration and rupture propagation given by the stress glut rate moments of total degree 2 by inverting long-period surface wave (LPSW) amplitude spectra. Kinematic and static models of the Izmit earthquake published in the literature are quite different from one another. In order to extract the characteristic features of this event, we calculate the same integral estimates directly from those models and compare them with those deduced from our inversion. While the equivalent rupture zone and the eastward directivity are consistent among all models, the LPSW solution displays a strong unilateral character of the rupture associated with a short rupture duration that is not compatible with the solutions deduced from the published models. With the aim of understand this discrepancy, we use simple equivalent kinematic models to reproduce the integral estimates of the considered rupture processes (including ours) by adjusting a few free parameters controlling the western and eastern parts of the rupture. We show that the joint analysis of the LPSW solution and source tomographies allows us to elucidate the scattering of source processes published for this earthquake and to discriminate between the models. Our results strongly suggest that (1) there was significant moment released on the eastern segment of the activated fault system during the Izmit earthquake; (2) the apparent rupture velocity decreases on this segment.

  15. Missed Iatrogenic Bladder Rupture Following Normal Vaginal Delivery. (United States)

    Baheti, Vidyasagar H; Wagaskar, Vinayak G; Patwardhan, Sujata K


    Bladder rupture following caesarian section is well documented complications. Intraperitoneal bladder rupture following normal vaginal delivery is very rare. Hereby, we present a case report of intraperitoneal bladder rupture presented late following normal vaginal delivery. We report a case of spontaneous intraperitoneal urinary bladder rupture following uneventful outlet forceps delivery in a 22-year-old primi gravid woman with gestational diabetes mellitus and fetal macrosomia who presented with large urinary ascites, anuria and renal failure. Emergent exploratory laparotomy with repair of the intraperitoneal bladder rupture helped to prevent its potential complications. Postpartum patients who undergo episiotomy or perineal repair may land up in unnoticed urinary retention which may rarely terminate in spontaneous urinary bladder rupture. Awareness of its manifestations amongst emergency physician would help to initiate appropriate timely management.

  16. Timing of Surface-Rupturing Earthquakes on the Philippine Fault Zone in Central Luzon Island, Philippines (United States)

    Tsutsumi, H.; Daligdig, J. A.; Goto, H.; Tungol, N. M.; Kondo, H.; Nakata, T.; Okuno, M.; Sugito, N.


    moderately west-dipping fault strands. We identified evidence for three faulting events during the past 2500 years. The timing of the most recent event is constrained sometime during the 15th and 19th century. Trenching at Sawmill south of downtown Gabaldon revealed that the most recent faulting on the Gabaldon fault occurred sometime after the 15th century AD, supporting the interpretation that the fault last ruptured during the 1645 earthquake. It thus appears that the San Jose, Digdig, and Gabaldon faults ruptured independently of one another in the last seismic cycle, although the left-stepping jogs separating these faults are less than 1.5 km wide, considerably smaller than the jogs that impeded rupture propagation during historical earthquakes worldwide. If the recurrence interval of the individual segments of the Philippine fault zone is longer than 500 years as we revealed for the Digdig and San Jose faults, the occurrence of about ten M>7 earthquakes during the past century may be interpreted as a temporal clustering of activity along the fault zone.

  17. Effects of Pre-Stress State and Propagation Velocity on Dynamic Fault Branching (United States)

    Kame, N.; Rice, J. R.; Dmowska, R.


    Major earthquakes seldom rupture along single planar faults. Instead there exist geometric complexities, including fault bends, branches and stepovers, which affect the rupture process, including nucleation and arrest. Here we consider a mode II rupture which propagates along a planar fault and encounters an intersection with a branching fault that makes an angle with the main fault. Analyses based on elastic stress fields near propagating ruptures suggest that whether a branch path will be followed or not, and whether branching to the extensional or compressional side is favored, depend on both the rupture propagation velocity as the branch is approached and on the pre-stress state before rupture arrives. See Kame and Yamashita (GJI, 139, 345-358, 1999) and Poliakov, Dmowska and Rice (JGR subm. 2001, The latter predicted that branching to the extensional side would be favored in all pre-stress states except for those in which the direction of maximum pre-compression Smax makes a shallow angle ψ with the fault plane. Angles ψ 45 ° result when the ratio is less than unity. Thus it is anticipated that the most favored side for rupture branching should switch from the extensional to the compressive side as we consider progressively larger σ oxx/σ oyy (which means progressively smaller ψ ). In order to test that and other predictions, we have adapted the elastodynamic boundary integral equation methodology of Kame and Yamashita to 2-dimensional Mode II ruptures along branched fault systems, to allow simulations of rupture in which the failure path is dynamically self-chosen. Failure in the modeling is described by a slip-weakening law for which the peak and residual strength, and strength at any particular amount of slip, is proportional to normal stress (-σ nn). Our current results are preliminary. Nevertheless, by comparing results for σ oxx/σ oyy = 0.8 with those for 1.4, we have established, e.g., that a 15

  18. Rupture process of the 2011 Lorca earthquake; Proceso de ruptura del sismo de Lorca de 11 mayo 2011

    Energy Technology Data Exchange (ETDEWEB)

    Buforn Peiro, E.; Pro Munoz, C.; Cesca, S.; Sanz de Galdeano, C.; Udias Vallina, A.


    The focal mechanism of the Lorca 2011 earthquake has been estimated from the inversion of the seismic moment tensor at regional and P and SH waveforms at tele seismic distances. Results shown a reverse fault with planes oriented in E-W direction and shallow focus (4km). The rupture process may be explained using a extended fault (circular fracture of 2 km radius) and rupture velocity of 2.2 km/s. From this model we have generated velocity and acceleration synthetic records for a range of distances from 20 to 200 km. From joint inversion of these synthetic and observed data we have identify the WSW{sub E}NE plane as the rupture plane, with the rupture propagating to the WSW. The 2011 Lorca earthquake is an evidence of the complexity of the region, where we have normal (Lorca, 1977), reverse (Mula, 1999 and Lorca 2011) and strike-slip (Bullas (2002, 2005) motions, while the regional stress pattern corresponds to horizontal N-S compression, with the exception of Lorca 1977 shock. (Author) 9 refs.

  19. Volcanic magma reservoir imaged as a low-density body beneath Aso volcano that terminated the 2016 Kumamoto earthquake rupture (United States)

    Miyakawa, Ayumu; Sumita, Tatsuya; Okubo, Yasukuni; Okuwaki, Ryo; Otsubo, Makoto; Uesawa, Shimpei; Yagi, Yuji


    We resolve the density structure of a possible magma reservoir beneath Aso, an active volcano on Kyushu Island, Japan, by inverting gravity data. In the context of the resolved structure, we discuss the relationship between the fault rupture of the 2016 Kumamoto earthquake and Aso volcano. Low-density bodies were resolved beneath central Aso volcano using a three-dimensional inversion with an assumed density contrast of ±0.3 g/cm3. The resultant location of the southern low-density body is consistent with a magma reservoir reported in previous studies. No Kumamoto aftershocks occur in the southern low-density body; this aseismic anomaly may indicate a ductile feature due to high temperatures and/or the presence of partial melt. Comparisons of the location of the southern low-density body with rupture models of the mainshock, obtained from teleseismic waveform and InSAR data, suggest that the rupture terminus overlaps the southern low-density body. The ductile features of a magma reservoir could have terminated rupture propagation. On the other hand, a northern low-density body is resolved in the Asodani area, where evidence of current volcanic activity is scarce and aftershock activity is high. The northern low-density body might, therefore, be derived from a thick caldera fill in the Asodani area, or correspond to mush magma or a high-crystallinity magma reservoir that could be the remnant of an ancient intrusion.[Figure not available: see fulltext.

  20. Rupture Process of the 2011 Tohoku-Oki Earthquake Based upon Joint Source Inversion of Teleseismic and GPS Data

    Directory of Open Access Journals (Sweden)

    Shiann-Jong Lee


    Full Text Available This study investigated 18 broadband teleseismic records and 451 near field GPS coseismic deformation data to determine the spatial and temporal slip distribution of the 2011 Tohoku-Oki earthquake (M 9.0. The results show a large triangular shaped slip zone with several asperities. The largest asperity centered above the hypocenter at about 5 - 30 km depth. A secondary large asperity was found in the deeper subduction zone beneath the hypocenter. The average slip on the fault is ~15 m and the maximum displacement on the biggest asperity is > 30 m. The temporal rupture process shows that the slip nucleated near the hypocenter at the beginning, and then ruptured to the shallow fault plane forming the largest asperity. The slip developed in the deeper subduction zone in the second stage. Finally, the rupture propagated toward the north and south of the fault along the Japan Trench. The source time function shows three segments of energy releases with two large peaks related to the development of the asperities. The overall rupture process is ~180 seconds. This source model coincides well with the aftershock distribution and provides a first-order information on the source complexity of the earthquake which is crucial for further studies.

  1. Finite rupture properties of the 2011 Lorca earthquake; Directividad y propiedades de la ruptura finita del terremoto de Lorca, 2011

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Comino, J. A.; Mancilla, F. L.; Sitch, D.; Morales, J.


    On 11 May 2011 an earthquake (M{sub w} = 5.2) hit the region of Murcia (Spain), shaking mainly the city of Lorca and causing extensive personal and material damage. We have estimated that it involved an oblique reverse-faulting mechanism with a shallow hypocentre (4.6 km) at only 5.5 km epicentral distance from Lorca city centre. Double-difference relocations yield a rupture length of {approx} 4 km and suggest a propagation of the rupture from the northeast to the southwest along the Alhama de Murcia fault. We obtained apparent source-time functions at each station using empirical Green's function deconvolution and applying the 4.6 M{sub w} foreshock and the 3.9 M{sub w} aftershock, both of them with a similar location and mechanism. Two methods of deconvolution were used: spectral division and iterative time domain. Both methods gave consistent, stable results, revealing a clear directivity effect. We have modelled apparent durations with a unilateral and asymmetric bilateral rupture, in both cases obtaining a rupture directivity of {approx} N215 degree E towards Lorca, which may have contributed to the unfavourable scenario caused by this event. (Author) 23 refs.

  2. Rupture Process of the 2011 Tohoku-Oki Earthquake Based upon Joint Source Inversion of Teleseismic and GPS Data

    Directory of Open Access Journals (Sweden)

    Shiann-Jong Lee


    Full Text Available This study investigated 18 broadband teleseismic records and 451 near field GPS coseismic deformation data to determine the spatial and temporal slip distribution of the 2011 Tohoku-Oki earthquake (M 9.0. The results show a large triangular shaped slip zone with several asperities. The largest asperity centered above the hypocenter at about 5 - 30 km depth. A secondary large asperity was found in the deeper subduction zone beneath the hypocenter. The average slip on the fault is ~15 m and the maximum displacement on the biggest asperity is > 30 m. The temporal rupture process shows that the slip nucleated near the hypocenter at the beginning, and then ruptured to the shallow fault plane forming the largest asperity. The slip developed in the deeper subduction zone in the second stage. Finally, the rupture propagated toward the north and south of the fault along the Japan Trench. The source time function shows three segments of energy releases with two large peaks related to the development of the asperities. The overall rupture process is ~180 seconds. This source model coincides well with the aftershock distribution and provides a first-order information on the source complexity of the earthquake which is crucial for further studies.

  3. A Rare Case of Adductor Longus Muscle Rupture (United States)

    van de Kimmenade, R. J. L. L.; van Bergen, C. J. A.; van Deurzen, P. J. E.; Verhagen, R. A. W.


    An adductor longus muscle rupture is a rare injury. This case report describes a 32-year-old patient with an adductor longus rupture. The trauma mechanism was a hyperabduction movement during a soccer game. Nonoperative treatment was initiated. After a follow-up of 4 years, the patient was without pain but a small swelling was still visible. This report describes the anatomy, pathophysiology, and evidence-based treatment of adductor longus rupture. PMID:25918663

  4. A Rare Case of Adductor Longus Muscle Rupture

    Directory of Open Access Journals (Sweden)

    R. J. L. L. van de Kimmenade


    Full Text Available An adductor longus muscle rupture is a rare injury. This case report describes a 32-year-old patient with an adductor longus rupture. The trauma mechanism was a hyperabduction movement during a soccer game. Nonoperative treatment was initiated. After a follow-up of 4 years, the patient was without pain but a small swelling was still visible. This report describes the anatomy, pathophysiology, and evidence-based treatment of adductor longus rupture.

  5. Misdiagnosed Uterine Rupture of an Advanced Cornual Pregnancy

    Directory of Open Access Journals (Sweden)

    Christian Linus Hastrup Sant


    Full Text Available Cornual pregnancy is a diagnostic and therapeutic challenge with potential severe consequences if uterine rupture occurs with following massive intraabdominal bleeding. We report a case of a misdiagnosed ruptured cornual pregnancy occurring at 21 weeks of gestation. Ultrasound examination and computer tomography revealed no sign of abnormal pregnancy. The correct diagnosis was first made at emergency laparotomy. Uterine rupture should be considered in pregnant women presenting with abdominal pain and haemodynamic instability.

  6. Misdiagnosed uterine rupture of an advanced cornual pregnancy

    DEFF Research Database (Denmark)

    Sant, Christian Linus Hastrup; Andersen, Poul Erik


    Cornual pregnancy is a diagnostic and therapeutic challenge with potential severe consequences if uterine rupture occurs with following massive intraabdominal bleeding. We report a case of a misdiagnosed ruptured cornual pregnancy occurring at 21 weeks of gestation. Ultrasound examination...... and computer tomography revealed no sign of abnormal pregnancy. The correct diagnosis was first made at emergency laparotomy. Uterine rupture should be considered in pregnant women presenting with abdominal pain and haemodynamic instability....

  7. Venous rupture complicating hemodialysis access angioplasty: percutaneous treatments and outcomes

    Energy Technology Data Exchange (ETDEWEB)

    La, Young Jong; Goo, Dong Erk; Kim, Dae Ho; Lee, Hae Kyoung; Hong, Hyun Suk; Kwon, Gui Hyang; Choi, Duk Lin; Ynag, Sung Boo [College of Medicine, Soonchunhyang Univ., Seoul (Korea, Republic of)


    To evaluate the usefulness of percutaneous management and prognosis in venous rupture during angioplasty of hemodialytic arteriovenous fistulas. Among 814 patients who underwent angioplasty on account of inadequate hemodialysis, 63(39 women and 24 men aged 20-78 (mean, 55.8) years) were included in this study. All 63 had peripheral venous stenosis. Venous rupture was diagnosed when contrast leakage was seen at venography after percutaneous angioplasty (PTA). In order to manage venous rupture, the sites at which this occurred were compressed manually for 3-5 minutes or blood flow was blocked with a balloon catheter for the same period. In one case, a stent was inserted at the rupture site. Using the Kaplan-Meier method, we investigated the patency rate of arteriovenous fistula (AVF) in cases of successful PTA. We also compared PTA patency rates in cases with and without peripheral venous rupture. Venous rupture occurred in 38 cephalic, 16 brachial, and 9 basilic veins. In 63 patients, bleeding stopped and in 54 (85.7 %) of thee, PTA was successful. Among the nine failed cases, dilatation was incomplete in five, though bleeding had stopped. In patients with brachial and cephalic vein rupture the venous tract at the rupture site was not located. Two patients underwent surgery: one of these experienced brachial venous rupture, with incontrollable bleeding, and the other had nerve compression symptoms due to hematoma. Among 54 patients in whom PTA was successful, the primary and secondary six-months rates for angioaccess were 47.9% and 81.2%, and the mean patency period was 6.1 and 15.8 months, respectively. In cases of non-venous rupture, the mean patency period was 9.6 months, significantly longer than in cases involving venous rupture (p=0.02). Venous rupture occurring during the PTA of hemodialytic AVF can be managed percutaneously.

  8. Alliance ruptures, impasses, and enactments: a relational perspective. (United States)

    Safran, Jeremy D; Kraus, Jessica


    Alliance ruptures, impasses, and transference-countertransference enactments are inevitable in therapy. A growing body of evidence suggests that repairing ruptures in the alliance is related to positive outcome (Safran, Muran, & Eubanks-Carter, 2011). Our research program has led to the development of training methods to enhance therapists' abilities to detect and work constructively with alliance ruptures and negative therapeutic process (Safran et al., 2014). This article outlines relevant theoretical underpinnings, intervention principles, and empirical findings.

  9. MRI in flexor tendon rupture after collagenase injection

    Energy Technology Data Exchange (ETDEWEB)

    Khurana, Shruti [Lady Hardinge Medical College, New Delhi (India); Wadhwa, Vibhor [University of Arkansas for Medical Sciences, Little Rock, AR (United States); Chhabra, Avneesh [UT Southwestern Medical Center, Dallas, TX (United States); Johns Hopkins University, Baltimore, MD (United States); Amirlak, Bardia [UT Southwestern Medical Center, Dallas, TX (United States)


    Flexor tendon rupture is an unusual complication following collagenase injection to relieve contractures. These patients require a close follow-up and in the event of tendon rupture, a decision has to be made whether to repair the tendon or manage the complication conservatively. The authors report the utility of MRI in the prognostication and management of a patient with Dupuytren's contracture, who underwent collagenase injection and subsequently developed flexor digitorum profundus tendon rupture. (orig.)

  10. Kinetics of hole nucleation in biomembrane rupture

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Evan [Biomedical Engineering, Boston University, Boston, MA 02215 (United States); Smith, Benjamin A, E-mail: [Departments of Physics and Pathology, University of British Columbia, Vancouver, BC, V6T 2A6 (Canada)


    The core component of a biological membrane is a fluid-lipid bilayer held together by interfacial-hydrophobic and van der Waals interactions, which are balanced for the most part by acyl chain entropy confinement. If biomembranes are subjected to persistent tensions, an unstable (nanoscale) hole will emerge at some time to cause rupture. Because of the large energy required to create a hole, thermal activation appears to be requisite for initiating a hole and the activation energy is expected to depend significantly on mechanical tension. Although models exist for the kinetic process of hole nucleation in tense membranes, studies of membrane survival have failed to cover the ranges of tension and lifetime needed to critically examine nucleation theory. Hence, rupturing giant ({approx}20 {mu}m) membrane vesicles ultra-slowly to ultra-quickly with slow to fast ramps of tension, we demonstrate a method to directly quantify kinetic rates at which unstable holes form in fluid membranes, at the same time providing a range of kinetic rates from <0.01 to >100 s{sup -1}. Measuring lifetimes of many hundreds of vesicles, each tensed by precision control of micropipette suction, we have determined the rates of failure for vesicles made from several synthetic phospholipids plus 1:1 mixtures of phospho- and sphingo-lipids with cholesterol, all of which represent prominent constituents of eukaryotic cell membranes. Plotted on a logarithmic scale, the failure rates for vesicles are found to rise dramatically with an increase in tension. Converting the experimental profiles of kinetic rates into changes of activation energy versus tension, we show that the results closely match expressions for thermal activation derived from a combination of meso-scale theory and molecular-scale simulations of hole formation. Moreover, we demonstrate a generic approach to transform analytical fits of activation energies obtained from rupture experiments into energy landscapes characterizing the

  11. 360-degree retinectomy for severe ocular rupture

    Institute of Scientific and Technical Information of China (English)

    ZHANG Mao-nian; JIANG Cai-hui


    Objective: To investigate the effect of 360-degree retinectomy for severe ocular rupture and evaluate the related factors associated with prognosis.Methods: A retrospective analysis was performed on 28 consecutive patients, 18 men and 10 women, with severe ocular rupture admitted to the Chinese PLA General Hospital between January 1999 and January 2002. The patients' ages ranged from 16 to 58 years, mean 29.5years. All operations were performed by the first author.All patients underwent standard 3-port pars plana vitrectomy with scleral encircling buckle,endophotocoagulation, and tamponaded with silicone oil.Lensectomy were performed on 15 eyes. 360-degree retinotomy and retinectomy were performed at anterior equator on 16 eyes, and posterior equator on 12 eyes.Results: During operation, all patients were confirmed to have vitreous hemorrhage and retinal detachment, in which hemorrhagic ciliary body detachment was found in 9 eyes, suprachoroidal hemorrhage in 12 eyes,retinal twisting like flower stalk in 11 eyes, and retinal incarceration in 17 eyes. Postoperative follow-up was conducted in 26 cases, ranged from 6 months to 46 months.Retinal reattachment achieved in 20 eyes (76. 9%), in which three patients' retina was reattached after revitrectomy. The silicone oil was removed at the fourth month in 8 eyes postoperatively. Corrected visual acuity of 0.02 or more was in 14 eyes (70. 0%) among the 20patients with reattached retina. Visual acuity of 0.05 or more was in 7 eyes ( 35.0 % ), and 0.1 or more was in 3eyes. The best visual acuity was 0.3 in 1 eye.Conclusions: Retinectomy may improve the prognosis of severe ocular rupture and save the visual function of some patients.

  12. Bladder rupture causing pseudo acute renal failure

    Directory of Open Access Journals (Sweden)

    Luciana Andrea Avena Smeili


    Full Text Available Bladder rupture is a rare condition associated with significant morbidityand mortality. It is classified into traumatic, nontraumatic or idiopathic andspontaneous. The nonspecific initial clinical presentation is followed bydiscomfort in the lower abdomen, oliguria, hematuria and ascitis. Laboratoryabnormalities simulate the picture of acute renal failure and occurs by amechanism called auto reverse dialysis, with absorption of excreta throughthe peritoneal membrane. The authors describe a case of bladder rupturein morphologically and functionally normal urinary bladder associated withalcohol intake in young healthy man, manifested by abdominal discomfort,pseudo renal failure and massive ascitis. The diagnosis was made by anabdominal multidetector computed tomography confirmed by the finding of7 cm laceration at laparotomy.

  13. Closed proximal muscle rupture of the biceps brachii in wakeboarders. (United States)

    Pascual-Garrido, Cecilia; Swanson, Britta L; Bannar, Stephen M


    Closed proximal muscle rupture of the biceps brachii is a rare injury. In this report, two cases of closed proximal muscle rupture of the biceps brachii after wakeboard traumas are described. Both patients presented with a swollen arm, weakness during flexion, and a mass in the affected forearm. Magnetic resonance imaging showed displacement of the biceps brachii into the forearm. The rupture was successfully treated with muscle removal in one case and muscle repair in the other. In patients with a wakeboard trauma and similar presentations, closed proximal muscle rupture of the biceps brachii should be suspected.

  14. Thrombosis and morphology of plaque rupture using optical coherence tomography

    Institute of Scientific and Technical Information of China (English)

    GUO Jun; CHEN Yun-dai; TIAN Feng; LIU Hong-bin; CHEN Lian; SUN Zhi-jun; REN Yi-hong


    Background Thrombosis following plaque rupture is the main cause of acute coronary syndrome,but not all plaque ruptures lead to thrombosis.There are limited in vivo data on the relationship between the morphology of ruptured plaque and thrombosis.Methods We used optical coherence tomography (OCT) to investigate the morphology of plaque rupture and its relation to coronary artery thrombosis in patients with coronary heart disease.Forty-two patients with coronary artery plaque rupture detected by OCT were divided into two groups (with or without thrombus) and the morphological characteristics of ruptured plaque,including fibrous cap thickness and broken cap site,were recorded.Results The fibrous cap of ruptured plaque with thrombus was significantly thinner compared to caps without thrombus ((57.00±17.00) μm vs.(96.00±48.00) μm; P=0.0076).Conclusions Plaque rupture associated with thrombosis occurs primarily in plaque covered by a thin fibrous cap.Thick fibrous caps are associated with greater stability of ruptured plaque.

  15. Risk factors affecting chronic rupture of the plantar fascia. (United States)

    Lee, Ho Seong; Choi, Young Rak; Kim, Sang Woo; Lee, Jin Yong; Seo, Jeong Ho; Jeong, Jae Jung


    Prior to 1994, plantar fascia ruptures were considered as an acute injury that occurred primarily in athletes. However, plantar fascia ruptures have recently been reported in the setting of preexisting plantar fasciitis. We analyzed risk factors causing plantar fascia rupture in the presence of preexisting plantar fasciitis. We retrospectively reviewed 286 patients with plantar fasciitis who were referred from private clinics between March 2004 and February 2008. Patients were divided into those with or without a plantar fascia rupture. There were 35 patients in the rupture group and 251 in the nonrupture group. The clinical characteristics and risk factors for plantar fascia rupture were compared between the 2 groups. We compared age, gender, the affected site, visual analog scale pain score, previous treatment regimen, body mass index, degree of ankle dorsiflexion, the use of steroid injections, the extent of activity, calcaneal pitch angle, the presence of a calcaneal spur, and heel alignment between the 2 groups. Of the assessed risk factors, only steroid injection was associated with the occurrence of a plantar fascia rupture. Among the 35 patients with a rupture, 33 had received steroid injections. The odds ratio of steroid injection was 33. Steroid injections for plantar fasciitis should be cautiously administered because of the higher risk for plantar fascia rupture. Level III, retrospective comparative study.

  16. Propagating Instabilities in Solids (United States)

    Kyriakides, Stelios


    Instability is one of the factors which limit the extent to which solids can be loaded or deformed and plays a pivotal role in the design of many structures. Such instabilities often result in localized deformation which precipitates catastrophic failure. Some materials have the capacity to recover their stiffness following a certain amount of localized deformation. This local recovery in stiffness arrests further local deformation and spreading of the instability to neighboring material becomes preferred. Under displacement controlled loading the propagation of the transition fronts can be achieved in a steady-state manner at a constant stress level known as the propagation stress. The stresses in the transition fronts joining the highly deformed zone to the intact material overcome the instability nucleation stresses and, as a result, the propagation stress is usually much lower than the stress required to nucleate the instability. The classical example of this class of material instabilities is L/"uders bands which tend to affect mild steels and other metals. Recent work has demonstrated that propagating instabilities occur in several other materials. Experimental and analytical results from four examples will be used to illustrate this point: First the evolution of L=FCders bands in mild steel strips will be revisited. The second example involves the evolution of stress induced phase transformations (austenite to martensite phases and the reverse) in a shape memory alloy under displacement controlled stretching. The third example is the crushing behavior of cellular materials such as honeycombs and foams made from metals and polymers. The fourth example involves the axial broadening/propagation of kink bands in aligned fiber/matrix composites under compression. The microstructure and, as a result, the micromechanisms governing the onset, localization, local arrest and propagation of instabilities in each of the four materials are vastly different. Despite this

  17. Heating and Weakening of Major Faults During Seismic Rupture (United States)

    Rice, J. R.


    The absence of significant heat flow from major fault zones, and scarcity of evidence for their seismic melting, means that during earthquake slip such zones could not retain shear strength comparable to the typically high static friction strength of rocks. One line of explanation is that they are actually statically weak, which could be because materials of exceptionally low friction (smectites, talc) accumulate along fault zones, or perhaps because pore pressure within the fault core is far closer to lithostatic than hydrostatic. Without dismissing either, the focus here is on how thermal processes during the rapid slips of seismic rupture can weaken a fault which is indeed statically strong. (The discussion also leaves aside another kind of non- thermal dynamic weakening, possible when there is dissimilarity in seismic properties across the fault, and/or in poroelastic properties and permeability within fringes of damaged material immediately adjoining the slip surface. Spatially nonuniform mode II slip like near a propagating rupture front may then induce a substantial reduction in the effective normal stress \\barσ.) The heating and weakening processes to be discussed divide roughly into two camps: (1) Those which are expected to be active from the start of seismic slip, and hence will be present in all earthquakes; and (2) Those that kick-in after threshold conditions of rise of temperature T or accumulation of slip are reached, and hence become a feature of larger, or at least deeper slipping, earthquakes. It has been argued that the two major players of (1) are as follows: (1.1) Flash heating and weakening of frictional contact asperities in rapid slip [Rice, 1999, 2006; Tullis and Goldsby, 2003; Goldsby and Hirth, 2006; Beeler et al., 2007; Yuan and Prakash, 2007]. That gives a strong velocity-weakening character to the friction coefficient, which is consistent with inducing self-healing rupture modes [Noda et al., 2006; Lu et al., 2007]. It is a process

  18. Long-term results after repair of ruptured and non-ruptured abdominal aortic aneurysm

    Directory of Open Access Journals (Sweden)

    Kuzmanović Ilija B.


    Full Text Available INTRODUCTION Abdominal aortic aneurysm can be repaired by elective procedure while asymptomatic, or immediately when it is complicated - mostly due to rupture. Treating abdominal aneurysm electively, before it becomes urgent, has medical and economical reason. Today, the first month mortality after elective operations of the abdominal aorta aneurysm is less than 3%; on the other hand, significant mortality (25%-70% has been recorded in patients operated immediately because of rupture of the abdominal aneurysm. In addition, the costs of elective surgical treatment are significantly lower. OBJECTIVE The objective of this study is to compare long-term survival of patients that underwent elective or immediate repair of abdominal aortic aneurysm (due to rupture, and to find out the factors influencing the long-term survival of these patients. MATERIAL AND METHODS Through retrospective review of prospectively collected data of the Institute for Cardiovascular Diseases of Clinical Center of Serbia, Belgrade, 56 patients that had elective surgery and 35 patients that underwent urgent operation due to rupture of abdominal aneurysm were followed up. Only the patients that survived 30 postoperative days were included in this review, and were followed up (ranging from 2 to 126 months. Electively operated patients were followed during 58.82 months on the average (range 7 to 122, and urgently operated were followed over 52.26 months (range 2 to 126. There was no significant difference of the length of postoperative follow-up between these two groups. RESULTS During this period, out of electively operated and immediately operated patients, 27 and 22 cases died, respectively. There was no significant difference (p>0,05a of long-term survival between these two groups. Obesity and early postoperative complications significantly decreased long-term survival of both electively and immediately operated patients. Graft infection, ventral hernia, aneurysm of

  19. 3D dynamic rupture simulation and local tomography studies following the 2010 Haiti earthquake (United States)

    Douilly, Roby

    The 2010 M7.0 Haiti earthquake was the first major earthquake in southern Haiti in 250 years. As this event could represent the beginning of a new period of active seismicity in the region, and in consideration of how vulnerable the population is to earthquake damage, it is important to understand the nature of this event and how it has influenced seismic hazards in the region. Most significantly, the 2010 earthquake occurred on the secondary Leogâne thrust fault (two fault segments), not the Enriquillo Fault, the major strike-slip fault in the region, despite it being only a few kilometers away. We first use a finite element model to simulate rupture along the Leogâne fault. We varied friction and background stress to investigate the conditions that best explain observed surface deformations and why the rupture did not to jump to the nearby Enriquillo fault. Our model successfully replicated rupture propagation along the two segments of the Leogâne fault, and indicated that a significant stress increase occurred on the top and to the west of the Enriquillo fault. We also investigated the potential ground shaking level in this region if a rupture similar to the Mw 7.0 2010 Haiti earthquake were to occur on the Enriquillo fault. We used a finite element method and assumptions on regional stress to simulate low frequency dynamic rupture propagation for the segment of the Enriquillo fault closer to the capital. The high-frequency ground motion components were calculated using the specific barrier model, and the hybrid synthetics were obtained by combining the low-frequencies ( 1Hz) from the stochastic simulation using matched filtering at a crossover frequency of 1 Hz. The average horizontal peak ground acceleration, computed at several sites of interest through Port-au-Prince (the capital), has a value of 0.35g. Finally, we investigated the 3D local tomography of this region. We considered 897 high-quality records from the earthquake catalog as recorded by

  20. 3D Dynamic Rupture Simulation Across a Complex Fault System: the Mw7.0, 2010, Haiti Earthquake (United States)

    Douilly, R.; Aochi, H.; Calais, E.; Freed, A. M.


    Earthquakes ruptures sometimes take place on a secondary fault and surprisingly do not activate an adjacent major one. The 1989 Loma Prieta earthquake is a classic case where rupture occurred on a blind thrust while the adjacent San Andreas Fault was not triggered during the process. Similar to Loma Prieta, the Mw7.0, January 12 2010, Haiti earthquake also ruptured a secondary blind thrust, the Léogâne fault, adjacent to the main plate boundary, the Enriquillo Plantain Garden Fault, which did not rupture during this event. Aftershock relocalizations delineate the Léogâne rupture with two north dipping segments with slightly different dip, where the easternmost segment had mostly dip-slip motion and the westernmost one had mostly strike-slip motion. In addition, an offshore south dipping structure inferred from the aftershocks to the west of the rupture zone coincides with the offshore Trois Baies reverse fault, a region of increase in Coulomb stress increase. In this study, we investigate the rupture dynamics of the Haiti earthquake in a complex fault system of multiple segments identified by the aftershock relocations. We suppose a background stress regime that is consistent with the type of motion of each fault and with the regional tectonic regime. We initiate a nucleation on the east segment of the Léogâne fault by defining a circular region with a 2 km radius where shear stress is slightly greater than the yield stress. By varying friction on faults and background stress, we find a range of plausible scenarios. In the absence of near-field seismic records of the event, we score the different models against the static deformation field derived from GPS and InSAR at the surface. All the plausible simulations show that the rupture propagates from the eastern to the western segment along the Léogâne fault, but not on the Enriquillo fault nor on the Trois Baies fault. The best-fit simulation shows a significant increase of shear stresses on the Trois Baies

  1. Earthquake behavior of variable rupture- scale on active faults and application of the cascade-rupturing model

    Institute of Scientific and Technical Information of China (English)



    This study reveals preliminarily the earthquake behavior of variable rupture-scale on active faults of the Chinese mainland, that is that on an individual fault portion earthquake¢s rupture-scale varies cycle to cycle, and hence earthquake¢s strength changes with time. The tendency of this variation has no necessity. On defining relative size of rupture scales, a statistical result shows that it is of the lowest probability that ruptures with the same scale occur in two successive cycles. While the rupture¢s scale in the preceding cycle is 2small2, the probability of the follow-ing rupture¢s scale being 2large2 is as many as 0.48. While the rupture¢s scale in the preceding cycle is 2middle2, the probability of the succeeding rupture being 2small2 or 2large2 scale is 0.69 or 0.25. While the rupture¢s scale in the preceding cycle is 2large2, the probability must be zero for the following rupture with 2large2 scale, and is 0.36 or 0.64 for the following rupture with 2small2 or 2middle2 scale. The author introduces and improves the cascade-rupturing model, and uses it to describe the variability and complexity of rupture scale on individual fault portions. Basic features of some active strike-slip faults on which cascade ruptures have occurred are summarized. Basing on these features the author proposes principles of cascade-rupture segmentation for this type of faults. As an ex-ample to application, the author segments one portion of the Anninghe fault zone, western Sichuan, for its future cascade rupture, and further assesses the probable strength and its corresponding probability of the coming earth-quake.

  2. Vegetative propagation of jojoba

    Energy Technology Data Exchange (ETDEWEB)

    Low, C.B.; Hackett, W.P.


    Development of jojoba as an economically viable crop requires improved methods of propagation and culture. Rooting experiments were performed on cutting material collected from wild jojoba plants. A striking seasonal fluctuation in rooting potential was found. Jojoba plants can be successfully propagated from stem cuttings made during spring, summer, and, to some extent, fall. Variability among jojoba plants may also play a role in rooting potential, although it is not as important as season. In general, the use of auxin (4,000 ppm indolebutyric acid) on jojoba cuttings during periods of high rooting potential promotes adventitious root formation, but during periods of low rooting potential it has no effect or is even slightly inhibitory. In the greenhouse, cutting-grown plants apparently reproductively matured sooner than those grown from seed. If this observation holds true for plants transplanted into the field, earlier fruit production by cutting--grown plants would mean earlier return of initial planting and maintenance costs.

  3. Propagation of Tau aggregates. (United States)

    Goedert, Michel; Spillantini, Maria Grazia


    Since 2009, evidence has accumulated to suggest that Tau aggregates form first in a small number of brain cells, from where they propagate to other regions, resulting in neurodegeneration and disease. Propagation of Tau aggregates is often called prion-like, which refers to the capacity of an assembled protein to induce the same abnormal conformation in a protein of the same kind, initiating a self-amplifying cascade. In addition, prion-like encompasses the release of protein aggregates from brain cells and their uptake by neighbouring cells. In mice, the intracerebral injection of Tau inclusions induced the ordered assembly of monomeric Tau, followed by its spreading to distant brain regions. Short fibrils constituted the major species of seed-competent Tau. The existence of several human Tauopathies with distinct fibril morphologies has led to the suggestion that different molecular conformers (or strains) of aggregated Tau exist.

  4. Stochastic wave propagation

    CERN Document Server

    Sobczyk, K


    This is a concise, unified exposition of the existing methods of analysis of linear stochastic waves with particular reference to the most recent results. Both scalar and vector waves are considered. Principal attention is concentrated on wave propagation in stochastic media and wave scattering at stochastic surfaces. However, discussion extends also to various mathematical aspects of stochastic wave equations and problems of modelling stochastic media.

  5. Bidirectional beam propagation method (United States)

    Kaczmarski, P.; Lagasse, P. E.


    A bidirectional extension of the beam propagation method (BPM) to optical waveguides with a longitudinal discontinuity is presented. The algorithm is verified by computing a reflection of the TE(0) mode from a semiconductor laser facet. The bidirectional BPM is applicable to other configurations such as totally reflecting waveguide mirrors, an abruption transition in a waveguide, or a waveguide with many discontinuities generating multiple reflections. The method can also be adapted to TM polarization.

  6. Gauge engineering and propagators

    Directory of Open Access Journals (Sweden)

    Maas Axel


    The dependence of the propagators on the choice of these complete gauge-fixings will then be investigated using lattice gauge theory for Yang-Mills theory. It is found that the implications for the infrared, and to some extent mid-momentum behavior, can be substantial. In going beyond the Yang-Mills case it turns out that the influence of matter can generally not be neglected. This will be briefly discussed for various types of matter.

  7. Diagnostic Modalities in Premature Rupture of Membranes

    Directory of Open Access Journals (Sweden)

    Fatma Eskicioğlu


    Full Text Available Objectives: Rupture of membranes prior to the onset of labor is known as Premature Rupture of Membranes (PROM. Early and correct diagnosis is crucial in order to prevent fetal and maternal risks that can be life threatening. We aimed to investigate the diagnostic ability of the tests in PROM. Materials and Methods: Nitrazine test, fern test, amnio-dye test, biochemical tests (insulin-like growth factor binding protein-1 and placental alpha microglobulin-1 were evaluated in terms of effectiveness in diagnosis of PROM. Results: A gold standard method has not yet been defined in PROM. Diagnostic tests (nitrazine test, fern test, Insulin-like Growth Factor Binding Protein-1 “IGFBP-1” and Placental Alpha Microglobulin-1 “PAMG-1” should be used when the diagnosis is not certain following history, examination with sterile speculum and ultrasonography evaluation. Conclusion: IGFBP-1 and PAMG-1 are tests based on bedside immunochromatographic method. Especially, PAMG-1 comes into prominence with its high sensitivity and specificity.

  8. Ruptures of the distal biceps tendon. (United States)

    Ward, James P; Shreve, Mark C; Youm, Thomas; Strauss, Eric J


    Distal biceps ruptures occur most commonly in middle-aged males and result from eccentric contraction of the biceps tendon. The injury typically presents with pain and a tearing sensation in the antecubital fossa with resultant weakness in flexion and supination strength. Physical exam maneuvers and diagnostic imaging aid in determining the diagnosis. Nonoperative management is reserved for elderly, low demand patients, while operative intervention is generally pursued for younger patients and can consist of nonanatomic repair to the brachialis or anatomic repair to the radial tuberosity. Anatomic repair through a one-incision or two-incision approach is commonplace, while the nonanatomic repairs are rarely performed. No clear advantage exists in operative management with a one-incision versus two-incision techniques. Chronic ruptures present a more difficult situation, and allograft augmentation is often necessary. Common complications after repair include transient nerve palsy, which often resolves, and heterotopic ossification. Despite these possible complications, most studies suggest that better patient outcomes are obtained with operative, anatomic reattachment of the distal biceps tendon.

  9. The Reasons of Steam Pipeline Elbow Rupture

    Directory of Open Access Journals (Sweden)

    Mesjasz A.


    Full Text Available In the paper the reasons for steam pipeline’s elbow material rupture, made of steel 13CrMo4-5 (15HM that is being used in the energetics. Based on the mechanical properties in the ambient temperature (Rm, Rp0,2 and elongation A5 and in the increased temperature (Rp0,2t it was found, that the pipeline elbow’s material sampled from the ruptured area has lower Rp0,2 i Rp0,2t by around 2% than it is a requirement for 13CrMo4-5 steel in it’s base state. The damage appeared as a result of complex stress state, that substantially exceeded the admissible tensions, what was the consequence of considerable structure degradation level. As a result of the microstructure tests on HITACHI S4200 microscope, the considerable development of the creeping process associates were found. Also the advances progress of the microstructure degradation was observed, which is substantial decomposition of bainite and multiple, with varied secretion size, and in most cases forming the micro cracks chains. With the use of lateral micro sections the creeping voids were observed, that creates at some places the shrinkage porosities clusters and micro pores.

  10. Probability of rupture of multiple fault segments (United States)

    Andrews, D.J.; Schwerer, E.


    Fault segments identified from geologic and historic evidence have sometimes been adopted as features limiting the likely extends of earthquake ruptures. There is no doubt that individual segments can sometimes join together to produce larger earthquakes. This work is a trial of an objective method to determine the probability of multisegment ruptures. The frequency of occurrence of events on all conjectured combinations of adjacent segments in northern California is found by fitting to both geologic slip rates and to an assumed distribution of event sizes for the region as a whole. Uncertainty in the shape of the distribution near the maximum magnitude has a large effect on the solution. Frequencies of individual events cannot be determined, but it is possible to find a set of frequencies to fit a model closely. A robust conclusion for the San Francisco Bay region is that large multisegment events occur on the San Andreas and San Gregorio faults, but single-segment events predominate on the extended Hayward and Calaveras strands of segments.

  11. Materials damaging and rupture - Volumes 1-2. General remarks, metallic materials. Non-metallic materials and biomaterials, assemblies and industrial problems;Endommagement et rupture des materiaux - Volumes 1-2. Generalites, materiaux metalliques. Materiaux non metalliques et biomateriaux, assemblages et problemes industriels

    Energy Technology Data Exchange (ETDEWEB)

    Clavel, M.; Bompard, P.


    The rupture and damaging of materials and structures is almost always and unwanted events which may have catastrophic consequences. Even if the mechanical failure causes can often be analyzed using a thorough knowledge of materials behaviour, the forecasting and prevention of failures remain difficult. While the macroscopic mechanical behaviour is often the result of average effects at the structure or microstructure scale, the damage is very often the result of the combination of load peaks, of localization effects and of microstructure defects. This book, presented in two volumes, takes stock of the state-of-the-art of the knowledge gained in the understanding and modelling of rupture and damaging phenomena of materials and structure, mostly of metallic type. It gives an outline of the available knowledge for other classes of materials (ceramics, biomaterials, geo-materials..) and for different types of applications (aeronautics, nuclear industry). Finally, it examines the delicate problem, but very important in practice, of the behaviour of assemblies. Content: Vol.1 - physical mechanisms of materials damaging and rupture; rupture mechanics; cyclic plasticity and fatigue crack growth; fatigue crack propagation; environment-induced cracking; contacts and surfaces. Vol.2 - glasses and ceramics; natural environments: soils and rocks; mechanical behaviour of biological solid materials: the human bone; contribution of simulation to the understanding of rupture mechanisms; assemblies damaging and rupture; industrial cases (behaviour of PWR pressure vessel steels, and thermal and mechanical stresses in turbojet engines). (J.S.)

  12. Rupture of Right Ventricular Free Wall Following Ventricular Septal Rupture in Takotsubo Cardiomyopathy with Right Ventricular Involvement. (United States)

    Sung, June Min; Hong, Sung Jin; Chung, In Hyun; Lee, Hye Young; Lee, Jae Hoon; Kim, Hyun Jung; Byun, Young Sup; Kim, Byung Ok; Rhee, Kun Joo


    Most patients diagnosed with takotsubo cardiomyopathies are expected to almost completely recover, and their prognosis is excellent. However, complications can occur in the acute phase. We present a case of a woman with takotsubo cardiomyopathy with right ventricular involvement who developed a rupture of the right ventricular free wall following ventricular septal rupture, as a consequence of an acute increase in right ventricular afterload by left-to-right shunt. Our case report illustrates that takotsubo cardiomyopathy can be life threatening in the acute phase. Ventricular septal rupture in biventricular takotsubo cardiomyopathy may be a harbinger of cardiac tamponade by right ventricular rupture.

  13. Regularization of rupture dynamics along bi-material interfaces: a parametric study and simulations of the Tohoku earthquake (United States)

    Scala, Antonio; Festa, Gaetano; Vilotte, Jean-Pierre


    Faults are often interfaces between materials with different elastic properties. This is generally the case of plate boundaries in subduction zones, where the ruptures extend for many kilometers crossing materials with strong impedance contrasts (oceanic crust, continental crust, mantle wedge, accretionary prism). From a physical point of view, several peculiar features emerged both from analogic experiments and numerical simulations for a rupture propagating along a bimaterial interface. The elastodynamic flux at the rupture tip breaks its symmetry, inducing normal stress changes and an asymmetric propagation. This latter was widely shown for rupture velocity and slip rate (e.g. Xia et al, 2005) and was supposed to generate an asymmetric distribution of the aftershocks (Rubin and Ampuero, 2007). The bimaterial problem coupled with a Coulomb friction law is ill-posed for a wide range of impedance contrasts, due to a missing length scale in the instantaneous response to the normal traction changes. The ill-posedness also results into simulations no longer independent of the grid size. A regularization can be introduced by delaying the tangential traction from the normal traction as suggested by Cochard and Rice (2000) and Ranjith and Rice (2000) δσeff α|v|+-v* δt = δσ (σn - σeff) where σeff represents the effective normal stress to be used in the Coulomb friction. This regularization introduces two delays depending on the slip rate and on a fixed time scale. In this study we performed a large number of 2D numerical simulations of in plane rupture with the spectral element method dynamic and we systematically investigated the effect of parameter selection on the rupture propagation, dissipation and radiation, by also performing a direct comparison with solutions provided by numerical and experimental results. We found that a purely time-dependent regularization requires a fine tuning rapidly jumping from a too fast, ineffective delay to a slow, invasive

  14. Two-dimensional Numerical Estimation of Stress Intensity Factors and Crack Propagation in Linear Elastic Analysis

    Directory of Open Access Journals (Sweden)

    A. Boulenouar


    Full Text Available When the loading or the geometry of a structure is not symmetrical about the crack axis, rupture occurs in mixed mode loading and the crack does not propagate in a straight line. It is then necessary to use kinking criteria to determine the new direction of crack propagation. The aim of this work is to present a numerical modeling of crack propagation under mixed mode loading conditions. This work is based on the implementation of the displacement extrapolation method in a FE code and the strain energy density theory in a finite element code. At each crack increment length, the kinking angle is evaluated as a function of stress intensity factors. In this paper, we analyzed the mechanical behavior of inclined cracks by evaluating the stress intensity factors. Then, we presented the examples of crack propagation in structures containing inclusions and cavities.

  15. Three-dimensional dynamic rupture simulation with a high-order discontinuous Galerkin method on unstructured tetrahedral meshes

    KAUST Repository

    Pelties, Christian


    Accurate and efficient numerical methods to simulate dynamic earthquake rupture and wave propagation in complex media and complex fault geometries are needed to address fundamental questions in earthquake dynamics, to integrate seismic and geodetic data into emerging approaches for dynamic source inversion, and to generate realistic physics-based earthquake scenarios for hazard assessment. Modeling of spontaneous earthquake rupture and seismic wave propagation by a high-order discontinuous Galerkin (DG) method combined with an arbitrarily high-order derivatives (ADER) time integration method was introduced in two dimensions by de la Puente et al. (2009). The ADER-DG method enables high accuracy in space and time and discretization by unstructured meshes. Here we extend this method to three-dimensional dynamic rupture problems. The high geometrical flexibility provided by the usage of tetrahedral elements and the lack of spurious mesh reflections in the ADER-DG method allows the refinement of the mesh close to the fault to model the rupture dynamics adequately while concentrating computational resources only where needed. Moreover, ADER-DG does not generate spurious high-frequency perturbations on the fault and hence does not require artificial Kelvin-Voigt damping. We verify our three-dimensional implementation by comparing results of the SCEC TPV3 test problem with two well-established numerical methods, finite differences, and spectral boundary integral. Furthermore, a convergence study is presented to demonstrate the systematic consistency of the method. To illustrate the capabilities of the high-order accurate ADER-DG scheme on unstructured meshes, we simulate an earthquake scenario, inspired by the 1992 Landers earthquake, that includes curved faults, fault branches, and surface topography. Copyright 2012 by the American Geophysical Union.

  16. Spontaneous rupture of hydatid cyst due to strain-defecation

    Institute of Scientific and Technical Information of China (English)

    Koray Daş; Selim Sözen; Abdurrahman Selçuk Uzun; Ebru Menekşe; Faruk Karateke; Ilhan Bali


    We report a case of strain-induced spontaneous rupture of hydatid cyst. Hydatid cyst rupture was diagnosed in a 19-year-old girl who presented with swelling and pain in the the right upper quadrant of sudden onset after straining for defecation.

  17. Morphological predictors of posterior communicating artery aneurysms rupture

    Institute of Scientific and Technical Information of China (English)

    Nan Lv; Yibin Fang; Ying Yu; Jinyu Xu; Jianmin Liu; Qinghai Huang


    Objective:The conflicting findings of previous morphological studies on intracranial aneurysm rupture may be caused by the different locations of aneurysms. We aimed to determine the independent risk factors of aneurysm rupture by focusing on only posterior communicating artery (PcomA) aneurysms. Methods:In 89 PcomA aneurysms (58 ruptured, 31 unruptured), clinical and morphological characteristics were compared between the ruptured and unruptured groups. Multivariate logistic regression analysis was performed to determine the independent predictors for the rupture status of PcomA aneurysms. Results:In univariate analyses, the aneurysm dome size, aspect ratio, size ratio, dome‐to‐neck ratio, and inflow angle were significant parameters. With multivariate analyses, only the aneurysm dome size and inflow angle were significantly associated with the rupture status of PcomA aneurysms. Conclusions:Morphology was related with rupture of PcomA aneurysms. The aneurysm dome size and inflow angle were found to be the independent parameters characterizing the rupture status of PcomA aneurysms.

  18. Unusual Cause of Acute Abdomen—Ruptured Retroperitoneal Paraganglioma

    Directory of Open Access Journals (Sweden)

    Kwok-Kay Yau


    Full Text Available Ruptured retroperitoneal paraganglioma is a rare cause of acute abdomen. Its clinical presentation and laparoscopic features have seldom been reported in the literature. Herein, we report a case of ruptured retroperitoneal paraganglioma that presented as acute abdomen, and its subsequent management.

  19. Diverse rupture processes in the 2015 Peru deep earthquake doublet. (United States)

    Ye, Lingling; Lay, Thorne; Kanamori, Hiroo; Zhan, Zhongwen; Duputel, Zacharie


    Earthquakes in deeply subducted oceanic lithosphere can involve either brittle or dissipative ruptures. On 24 November 2015, two deep (606 and 622 km) magnitude 7.5 and 7.6 earthquakes occurred 316 s and 55 km apart. The first event (E1) was a brittle rupture with a sequence of comparable-size subevents extending unilaterally ~50 km southward with a rupture speed of ~4.5 km/s. This earthquake triggered several aftershocks to the north along with the other major event (E2), which had 40% larger seismic moment and the same duration (~20 s), but much smaller rupture area and lower rupture speed than E1, indicating a more dissipative rupture. A minor energy release ~12 s after E1 near the E2 hypocenter, possibly initiated by the S wave from E1, and a clear aftershock ~165 s after E1 also near the E2 hypocenter, suggest that E2 was likely dynamically triggered. Differences in deep earthquake rupture behavior are commonly attributed to variations in thermal state between subduction zones. However, the marked difference in rupture behavior of the nearby Peru doublet events suggests that local variations of stress state and material properties significantly contribute to diverse behavior of deep earthquakes.

  20. Spontaneous rupture of a liver hemangioma. A case report. (United States)

    Guillén-Paredes, María Pilar; Martínez Fernández, Josefa; Morales González, Álvaro; Pardo-García, José Luis


    Spontaneous rupture of a liver hemangioma is a very uncommon disease, but extremely seriousness because it is associated to a 75% of mortality caused by hipovolemic shock. A case of an spontaneous rupture of liver hemangioma, which was previously unknow, is presented.

  1. Hemorrhagic shock due to spontaneous rupture of adrenal pheochromocytoma

    Directory of Open Access Journals (Sweden)

    Bittencourt José A.


    Full Text Available The spontaneous rupture of an adrenal pheochromocytoma is an extremely rare event; however, it is potentially fatal. We report a case of spontaneous rupture of pheochromocytoma followed by an extensive retroperitoneal hematoma and hypovolemic shock. The correct diagnostic assessment determined the adequate surgical approach and a favorable outcome for the patient.

  2. Pulse-Like Rupture Induced by Three-Dimensional Fault Zone Flower Structures

    KAUST Repository

    Pelties, Christian


    . The first healing mechanism is dominant for events with hypocenter inside the LVFZ. The second one is dominant if the hypocenter is deeper than a shallow LVFZ. These results suggest that the depth-dependence of rise time might help constrain the depth extent of the LVFZ. We also show that ruptures can spontaneously stop in flower-like LVFZs with uniform velocity reduction, but continue propagating as slip pulses if velocity reduction is depth-dependent.

  3. Wave propagation in elastic solids

    CERN Document Server

    Achenbach, Jan


    The propagation of mechanical disturbances in solids is of interest in many branches of the physical scienses and engineering. This book aims to present an account of the theory of wave propagation in elastic solids. The material is arranged to present an exposition of the basic concepts of mechanical wave propagation within a one-dimensional setting and a discussion of formal aspects of elastodynamic theory in three dimensions, followed by chapters expounding on typical wave propagation phenomena, such as radiation, reflection, refraction, propagation in waveguides, and diffraction. The treat

  4. Stochastic model in microwave propagation

    Energy Technology Data Exchange (ETDEWEB)

    Ranfagni, A. [“Nello Carrara” Institute of Applied Physics, CNR Florence Research Area, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Mugnai, D., E-mail: [“Nello Carrara” Institute of Applied Physics, CNR Florence Research Area, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy)


    Further experimental results of delay time in microwave propagation are reported in the presence of a lossy medium (wood). The measurements show that the presence of a lossy medium makes the propagation slightly superluminal. The results are interpreted on the basis of a stochastic (or path integral) model, showing how this model is able to describe each kind of physical system in which multi-path trajectories are present. -- Highlights: ► We present new experimental results on electromagnetic “anomalous” propagation. ► We apply a path integral theoretical model to wave propagation. ► Stochastic processes and multi-path trajectories in propagation are considered.

  5. Temporal scaling in information propagation. (United States)

    Huang, Junming; Li, Chao; Wang, Wen-Qiang; Shen, Hua-Wei; Li, Guojie; Cheng, Xue-Qi


    For the study of information propagation, one fundamental problem is uncovering universal laws governing the dynamics of information propagation. This problem, from the microscopic perspective, is formulated as estimating the propagation probability that a piece of information propagates from one individual to another. Such a propagation probability generally depends on two major classes of factors: the intrinsic attractiveness of information and the interactions between individuals. Despite the fact that the temporal effect of attractiveness is widely studied, temporal laws underlying individual interactions remain unclear, causing inaccurate prediction of information propagation on evolving social networks. In this report, we empirically study the dynamics of information propagation, using the dataset from a population-scale social media website. We discover a temporal scaling in information propagation: the probability a message propagates between two individuals decays with the length of time latency since their latest interaction, obeying a power-law rule. Leveraging the scaling law, we further propose a temporal model to estimate future propagation probabilities between individuals, reducing the error rate of information propagation prediction from 6.7% to 2.6% and improving viral marketing with 9.7% incremental customers.

  6. Temporal scaling in information propagation (United States)

    Huang, Junming; Li, Chao; Wang, Wen-Qiang; Shen, Hua-Wei; Li, Guojie; Cheng, Xue-Qi


    For the study of information propagation, one fundamental problem is uncovering universal laws governing the dynamics of information propagation. This problem, from the microscopic perspective, is formulated as estimating the propagation probability that a piece of information propagates from one individual to another. Such a propagation probability generally depends on two major classes of factors: the intrinsic attractiveness of information and the interactions between individuals. Despite the fact that the temporal effect of attractiveness is widely studied, temporal laws underlying individual interactions remain unclear, causing inaccurate prediction of information propagation on evolving social networks. In this report, we empirically study the dynamics of information propagation, using the dataset from a population-scale social media website. We discover a temporal scaling in information propagation: the probability a message propagates between two individuals decays with the length of time latency since their latest interaction, obeying a power-law rule. Leveraging the scaling law, we further propose a temporal model to estimate future propagation probabilities between individuals, reducing the error rate of information propagation prediction from 6.7% to 2.6% and improving viral marketing with 9.7% incremental customers.

  7. Control of seafloor roughness on earthquake rupture behavior (United States)

    Bilek, Susan L.; Schwartz, Susan Y.; Deshon, Heather R.


    Earthquake rupture complexity is described for three recent large underthrusting earthquakes along the Costa Rican subduction zone, the 1983 Osa, 1990 Nicoya Gulf, and 1999 Quepos events. These earthquakes occurred in regions characterized by distinctly different morphologic features on the subducting plate. The 1990 and 1999 events occurred along linear projections of subducting seamount chains and had fairly simple earthquake rupture histories. Both events are interpreted as failure of the basal contact of closely spaced isolated seamounts acting as asperities. In contrast, the 1983 event occurred along the subducting Cocos Ridge and had a complex rupture history. Comparison of rupture characteristics of these large underthrusting earthquakes with size and location of subducting features provides evidence that seamounts can be subducted to seismogenic depths and that variations in seafloor bathymetry of the subducting plate strongly influence the earthquake rupture process.

  8. Use of fluroquinolone and risk of Achilles tendon rupture

    DEFF Research Database (Denmark)

    Sode, Jacob; Obel, Niels; Hallas, Jesper


    OBJECTIVE: Several case-control studies have reported that the use of fluoroquinolone increases the risk of rupture of the Achilles tendon. Our aim was to estimate this risk by means of a population-based cohort approach. SETTING: Data on Achilles tendon ruptures and fluoroquinolone use were...... retrieved from three population-based databases that include information on residents of Funen County (population: 470,000) in primary and secondary care during the period 1991-1999. A study cohort of all 28,262 first-time users of fluoroquinolone and all incident cases of Achilles tendon ruptures were...... identified. MAIN OUTCOME MEASURES: The incidence rate of Achilles tendon ruptures among users and non-users of fluoroquinolones and the standardised incidence rate ratio associating fluoroquinolon use with Achilles tendon rupture were the main outcome measures. RESULTS: Between 1991 and 2002 the incidence...

  9. Spontaneous rupture of multifocal hepatocellular carcinoma: case report

    Directory of Open Access Journals (Sweden)

    Özen Ö


    Full Text Available Özkan Özen, Alptekin Tosun, Çiğdem Akgül Department of Radiology, Faculty of Medicine, Giresun University, Giresun, Turkey Abstract: Hemoperitoneum due to nontraumatic liver rupture is rare. The most common cause of nontraumatic rupture of the liver is hepatocellular carcinoma (HCC. The other causes of nontraumatic liver ruptures are peliosis hepatis, polyarteritis nodosa, systemic lupus erythematosus, preeclampsia, metastatic carcinoma, and other primary liver tumors. In this report, we present the computed tomography findings of spontaneous liver rupture in a 52-year-old male patient due to multifocal HCC, with the diagnosis proven by surgical specimen. Keywords: computed tomography, hemoperitoneum, liver, nontraumatic liver rupture

  10. Incidence of plantar fascia ruptures following corticosteroid injection. (United States)

    Kim, Chul; Cashdollar, Michael R; Mendicino, Robert W; Catanzariti, Alan R; Fuge, LaDonna


    Plantar fasciitis is commonly treated with corticosteroid injections to decrease pain and inflammation. Therapeutic benefits often vary in terms of efficacy and duration. Rupture of the plantar fascia has been reported as a possible complication following corticosteroid injection. A retrospective chart review of 120 patients who received corticosteroid injection for plantar fasciitis was performed at the authors' institution to determine the incidence of plantar fascia rupture. The plantar fascia rupture was diagnosed clinically and confirmed with magnetic resonance imaging. Various factors were analyzed, including the number of injections, interval between injections, body mass index (BMI), and activity level. Four patients (2.4%) consequently experienced plantar fascia rupture following an average of 2.67 injections. The average BMI of these patients was 38.6 kg/m². The authors conclude that corticosteroid injection therapy appears to be a safe and effective form of nonoperative treatment with minimal complications and a relatively low incident of plantar fascia rupture.

  11. Chest radiography in acute traumatic rupture of the thoracic aorta

    Energy Technology Data Exchange (ETDEWEB)

    Heystraten, F.M.; Rosenbusch, G.; Kingma, L.M.; Lacquet, L.K.; Boo, T. de; Lemmens, W.A.

    Of 123 patients who had suffered blunt trauma to the chest traumatic aortic rupture was eventually confirmed in 61 and absent in 62 patients. The chest radiographs of these patients were examined for 15 signs reported in the literature as being associated with traumatic aortic rupture. Although many individual signs were significantly more frequent in the aortic rupture group they were not useful in differentiating between patients with and those without rupture of the aorta. By using discriminant analysis combining 2 or 3 signs, patients were classified as having aortic rupture or not. The best discrimination between the two groups was obtained using the combined signs of a widened paratracheal stripe, and opacified pulmonary window, a widened right paraspinal interface and a displaced nasogastric tube.

  12. Malignant fibrous histiocytoma presenting as hemoperitoneum mimicking hepatocellular carcinoma rupture

    Institute of Scientific and Technical Information of China (English)


    Malignant fibrous histiocytoma (MFH) is a pleomorphic mesenchynal sarcoma. It is uncommonly arises primarily from the intra-peritoneal cavity. Primary peritoneal MFH with tumor bleeding and rupture is rare. We describe the imaging features of a 70-year-old patient presenting with ruptured hemorrhagic peritoneal MFH at subhepatic area, accompanied by massive hemoperitoneum,mimicking a ruptured pedunculated hepatocellular carcinoma. Computed tomography (CT) revealed a large heterogeneous enhanced subhepatic mass with adjacent liver, gallbladder and colon invasion. Tumor hemorrhage and rupture complicated with peritoneal seeding and massive bloody ascites were also detected.Angiography showed a hypervascular tumor fed by enlarged right hepatic arteries, cystic artery and omental branches of gastroepiploic artery. The patient underwent laparotomy for tumor resection, but the tumor recurred one month after operation. To our knowledge, the CT appearance of ruptured intraperitoneal MFH complicated by hemoperitoneum has not been previously described.

  13. [Histologic chorioamnionitis prevalence in patients with premature rupture membranes]. (United States)

    Garcia-de la Torre, José Ignacio; Delgado-Rosas, Antonio; Gonzélez-Cantú, Gerardo


    Search Histologic Chorioamnionitis frequency in patients in week 28 (+/-) and pregnancy with premature rupture of membranes. Retrospective and observational study in which we studied all patients who came between June 28, 2011 and November 15, 2011 to receive obstetric care in the service of Tocochirurgical of the University Hospital of Saltillo, with greater than or equal 28 weeks of pregnancy. 598 patients were studied, and the frequency of premature rupture of membranes with histologic chorioamnionitis at term patients was, respectively, 1.7 and 5.3% in preterm labor. In the total sample frequency of histologic chorioamnionitis was 0.6% (4 patients) and, of these, 25% were term and 75% with preterm rupture. In patients with premature rupture of membranes the clinical chorioamnionitis was 0% valued by the criteria of Gibbs. The premature rupture of membranes is a risk factor important for histological chorioamnionitis. To decrease risk factors and possible complications, an established protocol must be taken.

  14. Validity of Parametrized Quark Propagator

    Institute of Scientific and Technical Information of China (English)

    ZHUJi-Zhen; ZHOULi-Juan; MAWei-Xing


    Based on an extensively study of the Dyson-Schwinger equations for a fully dressed quark propagator in the “rainbow”approximation, a parametrized fully dressed quark propagator is proposed in this paper. The parametrized propagator describes a confining quark propagator in hadron since it is analytic everywhere in complex p2-plane and has no Lemmann representation. The validity of the new propagator is discussed by comparing its predictions on selfenergy functions A/(p2), Bl(p2) and effective mass M$(p2) of quark with flavor f to their corresponding theoretical results produced by Dyson-Schwinger equations. Our comparison shows that the parametrized quark propagator is a good approximation to the fully dressed quark propagator given by the solutions of Dyson-Schwinger equations in the rainbow approximation and is convenient to use in any theoretical calculations.

  15. Validity of Parametrized Quark Propagator

    Institute of Scientific and Technical Information of China (English)

    ZHU Ji-Zhen; ZHOU Li-Juan; MA Wei-Xing


    Based on an extensively study of the Dyson-Schwinger equations for a fully dressed quark propagator in the "rainbow" approximation, a parametrized fully dressed quark propagator is proposed in this paper. The parametrized propagator describes a confining quark propagator in hadron since it is analytic everywhere in complex p2-plane and has no Lemmann representation. The validity of the new propagator is discussed by comparing its predictions on selfenergy functions Af(p2), Bf(p2) and effective mass Mf(p2) of quark with flavor f to their corresponding theoretical results produced by Dyson-Schwinger equations. Our comparison shows that the parametrized quark propagator is a good approximation to the fully dressed quark propagator given by the solutions of Dyson-Schwinger equations in the rainbow approximation and is convenient to use in any theoretical calculations.

  16. PIV uncertainty propagation (United States)

    Sciacchitano, Andrea; Wieneke, Bernhard


    This paper discusses the propagation of the instantaneous uncertainty of PIV measurements to statistical and instantaneous quantities of interest derived from the velocity field. The expression of the uncertainty of vorticity, velocity divergence, mean value and Reynolds stresses is derived. It is shown that the uncertainty of vorticity and velocity divergence requires the knowledge of the spatial correlation between the error of the x and y particle image displacement, which depends upon the measurement spatial resolution. The uncertainty of statistical quantities is often dominated by the random uncertainty due to the finite sample size and decreases with the square root of the effective number of independent samples. Monte Carlo simulations are conducted to assess the accuracy of the uncertainty propagation formulae. Furthermore, three experimental assessments are carried out. In the first experiment, a turntable is used to simulate a rigid rotation flow field. The estimated uncertainty of the vorticity is compared with the actual vorticity error root-mean-square, with differences between the two quantities within 5-10% for different interrogation window sizes and overlap factors. A turbulent jet flow is investigated in the second experimental assessment. The reference velocity, which is used to compute the reference value of the instantaneous flow properties of interest, is obtained with an auxiliary PIV system, which features a higher dynamic range than the measurement system. Finally, the uncertainty quantification of statistical quantities is assessed via PIV measurements in a cavity flow. The comparison between estimated uncertainty and actual error demonstrates the accuracy of the proposed uncertainty propagation methodology.

  17. Ionospheric Radio Propagation (United States)


    applies Chapter 2 presents in simple form the mathe - principles which have been found to work in prac- matical theory underlying the propagation of...6.17, which was described under sec- L713 412 812.111 410.511171IS1&41&716.3 A& tion 6.5 above, and read the value of the muf for muFi .-f------ - 01...twepse, 71. mathe 1measuring virtual 6elghts, is world contour charts. 57; zero distance, 73. Se .1.. Contour chairt MCNiII, A. 0., 106 G Median value

  18. Sequential Back—Propagation

    Institute of Scientific and Technical Information of China (English)

    王晖; 刘大有; 等


    In this paper we consider the problem of sequential processing and present a sequential model based on the back-propagation algorithm.This model is intended to deal with intrinsically sequential problems,such as word recognition,speech recognition,natural language understanding.This model can be used to train a network to learn the sequence of input patterns,in a fixed order or a random order.Besides,this model is open- and partial-associative,characterized as “resognizing while accumulating”, which, as we argue, is mental cognition process oriented.

  19. Ruptured Giant Omphalocele. A Case Report

    Directory of Open Access Journals (Sweden)

    Víctor Manuel González Valdez


    Full Text Available Omphalocele is one of the abdominal wall defects. It can be associated with other malformations including imperforate anus, agenesis of the colon, bladder exstrophy and cardiovascular disease, frequently leading to non-viable fetuses. A case of a female newborn who was prematurely delivered (35.3 weeks in Belize with low birth weight (1860 g is presented. This first-born child required emergency surgery at ten hours of life for ruptured giant omphalocele associated with tetralogy of Fallot, hypoglycemia, and severe general malaise. The aim of this report is to present the diagnostic and therapeutic procedures in such cases. Given the appropriate prenatal diagnosis implemented in Cuba, it is unusual for Cuban doctors, except those working abroad, to treat these patients; hence, this paper may be useful in the teaching context.

  20. Imaging of diaphragmatic rupture after trauma

    Energy Technology Data Exchange (ETDEWEB)

    Eren, S. [Department of Radiology, Faculty of Medicine, Atatuerk University, Erzurum (Turkey)]. E-mail:; Kantarci, M. [Department of Radiology, Faculty of Medicine, Atatuerk University, Erzurum (Turkey); Okur, A. [Department of Radiology, Faculty of Medicine, Atatuerk University, Erzurum (Turkey)


    Traumatic rupture of the diaphragm usually results from blunt or penetrating injuries, or iatrogenic causes. Most cases are initially overlooked in the acute phase because they present with variable clinical and radiological signs. An overlooked diaphragmatic injury presents as a hernia many years later with potentially serious complications, therefore selection of the most appropriate radiological technique and accurate diagnosis of traumatic diaphragmatic hernias (DH) on the first admission is important. Although the diagnosis of diaphragmatic injuries is problematic, various investigations may be used for diagnosis. We describe the imaging findings of 19 traumatic DH cases with various imaging techniques. The patients were acute trauma cases or cases with prior trauma or thoraco-abdominal surgery with clinical suspicion of DH. An evaluation of the imaging techniques used in the diagnosis of DH is presented.

  1. Essentials of anterior cruciate ligament rupture management. (United States)

    Klinge, Stephen A; Sawyer, Gregory A; Hulstyn, Michael J


    Anterior cruciate ligament (ACL) rupture is a common knee injury and an understanding of current medical knowledge regarding its management is essential. Accurate and prompt diagnosis requires an awareness of injury mechanisms and risk factors, common symptoms and physical/radiologic findings. Early mobilization and physical therapy improves outcomes regardless of treatment modality. Many older patients regain sufficient stability and function after non-operative rehabilitation. Early ACL reconstruction is appropriate for younger patients and those who engage in activities requiring frequent pivoting and rapid direction changes. ACL surgery involves reconstruction of the torn ligament tissue with various replacement graft options, each with advantages and disadvantages. The guidance of a knowledgeable and experienced therapist is required throughout an intensive and prolonged rehabilitation course. Generally excellent outcomes and low complication rates are expected, but treatment does not prevent late osteoarthritis.

  2. Protecting geothermal operations with rupture disks

    Energy Technology Data Exchange (ETDEWEB)

    Porter, D.W.


    All geothermal operations begin similarly in that oil field type drilling methods are used to produce a geothermal well that will produce naturally occurring steam or hot water. In some cases, parallel wells are drilled for the purpose of injecting water into one of the 2 to provide additional water that can be heated and returned from the remaining bore, thus enhancing the output. All geothermal operations also conclude similarly, with the heat-spent condensate (brine) being re-injected into the ground, if for no other purpose than disposal. In steam operations (vs. hot water), a condensing unit is required to convert any remaining steam into brine before re-injection. The potential rupture disk applications are outlined.

  3. Pneumatic Rupture of Rectosigmoid; a Case Report. (United States)

    Montazeri, Mohammad; Farhangi, Bahman; Montazeri, Mahmood


    Pneumatic rectosigmoid rapture is usually occurred following the inappropriate fun by direct entering a high volume of the air through the pneumatic device to the anus. Such an event was reported for the first time in 1904 by Stone. Diagnosis and treatment of such injuries are often delayed because of some social limitations and preventing the patient form explaining the event. Colon sigmoid rupture and pneumoperitoneum is one of the most dangerous and life treating complications of entering a high volume of the air to the rectum in a short time. There are only a few reports regarding the similar cases. Here, a case of pneumatic rectosigmoid rapture was reported in a 53 year-old male following an inappropriate fun.

  4. Pneumatic Rupture of Rectosigmoid; a Case Report

    Directory of Open Access Journals (Sweden)

    Mohammad Montazeri


    Full Text Available Pneumatic rectosigmoid rapture is usually occurred following the inappropriate fun by direct entering a high volume of the air through the pneumatic device to the anus. Such an event was reported for the first time in 1904 by Stone. Diagnosis and treatment of such injuries are often delayed because of some social limitations and preventing the patient form explaining the event. Colon sigmoid rupture and pneumoperitoneum is one of the most dangerous and life treating complications of entering a high volume of the air to the rectum in a short time. There are only a few reports regarding the similar cases. Here, a case of pneumatic rectosigmoid rapture was reported in a 53 year-old male following an inappropriate fun.

  5. Soft, Brown Rupture: Clinical Signs and Symptoms Associated with Ruptured PIP Breast Implants

    Directory of Open Access Journals (Sweden)

    Yvette Godwin, FRCS


    Conclusions: Preoperative signs can be predictive of PIP implant failure. Brown-stained implants are more prone to rupture. The presence of iodine in the gel suggests unacceptable permeability of the shell early in the implant’s life span. A noninvasive screening test to detect brown implants in situ could help identify implants at risk of failure in those who elect to keep their implants.

  6. Light Propagation Volumes


    Mikulica, Tomáš


    Cílem diplomové práce je popsat různé metody výpočtu globálního osvětlení scény včetně techniky Light Propagation Volumes. Pro tuto metodu jsou podrobně popsány všechny tři kroky výpočtu: injekce, propagace a vykreslení. Dále je navrženo několik vlastních rozšíření zlepšující grafickou kvalitu metody. Části návrhu a implementace jsou zaměřeny na popis scény, zobrazovacího systému, tvorby stínů, implementace metody Light Propagation Volumes a navržených rozšíření. Práci uzavírá měření, porovná...

  7. Rupture by Damage Accumulation in Rocks

    CERN Document Server

    Amitrano, David


    The deformation of rocks is associated with microcracks nucleation and propagation, i.e. damage. The accumulation of damage and its spatial localization lead to the creation of a macroscale discontinuity, so-called "fault" in geological terms, and to the failure of the material, i.e. a dramatic decrease of the mechanical properties as strength and modulus. The damage process can be studied both statically by direct observation of thin sections and dynamically by recording acoustic waves emitted by crack propagation (acoustic emission). Here we first review such observations concerning geological objects over scales ranging from the laboratory sample scale (dm) to seismically active faults (km), including cliffs and rock masses (Dm, hm). These observations reveal complex patterns in both space (fractal properties of damage structures as roughness and gouge), time (clustering, particular trends when the failure approaches) and energy domains (power-law distributions of energy release bursts). We use a numerical...

  8. Dynamic Rupture Model of the 2004 Sumatra-Andaman Megathrust Earthquake (United States)

    Madden, Elizabeth H.; Ulrich, Thomas; Gabriel, Alice-Agnes


    The M 9.1-9.3 Sumatra-Andaman earthquake of 26 December 2004 caused violent shaking and generated a tsunami wave that was up to 50 m high along the northern coast of Sumatra. While various finite-source models have been proposed, here we present a physically realistic dynamic rupture model of the megathrust earthquake. To accomplish this, we use SeisSol, a highly parallelized software package that runs on modern supercomputers. Numerically, it follows an ADER-DG scheme to solve the spontaneous dynamic earthquake rupture problem with high-order accuracy in space and time. SeisSol accommodates unstructured tetrahedral meshes that decrease computational expense by allowing for a high-resolution mesh where required, including along the non-planar subducting fault and to capture the bathymetry, as well as a lower resolution mesh in other regions. In the SeisSol model, the slip interface follows the geometry of Slab1.0 to the south and aftershock locations to the north. 4 km resolution bathymetry from GEBCO is incorporated at the ocean floor. Material properties are taken from Crust1.0 and are laterally homogeneous, but vertically varying. The model results are constrained by the overall characteristics of the rupture, including the magnitude, propagation speed, and extent along strike, as well as surface displacements recorded with GPS satellites. We aim to resolve the influence of source dynamics on ground displacement and the potential impacts on tsunami generation in the framework of the ASCETE project ("Advanced Simulation of Coupled Earthquake and Tsunami Events",

  9. Total ruptures of the extensor apparatus of the knee

    Directory of Open Access Journals (Sweden)

    Diogo Moura

    Full Text Available ABSTRACT OBJECTIVE: This was a retrospective case-control study on total ruptures of the extensor apparatus of the knee, aimed to compare patella fractures with tendinous ruptures. METHODS: The sample included 190 patients and 198 total ruptures of the knee extensor apparatus. All patients were evaluated by the same examiner after a minimum one-year follow-up. RESULTS: Tendinous ruptures occurred most frequently in men, in younger patients, and had better clinical and functional outcomes when compared with patella fractures; however, the former presented higher levels of thigh atrophy. Patella fractures occurred most frequently in women and in older patients and caused most frequently caused residual pain, muscle weakness, and limitations in daily activities. Comminuted fractures were related to high-energy trauma, lower clinical and functional outcomes, and higher levels of residual pain and osteosynthesis failure. Early removal of osteosynthesis material was related to better outcomes. Regarding the tendinous ruptures, over half of the patients presented risk conditions for tendinous degeneration; a longer delay until surgery was related to lower Kujala scores. CONCLUSION: The surgical repair of bilateral ruptures of the knee extensor apparatus resulted in satisfactory clinical and functional outcomes, which were better for tendinous ruptures when compared with patella fractures. However, these lesions are associated with non-negligible levels of residual pain, muscle weakness, atrophy, and other complications.

  10. Shigella subverts the host recycling compartment to rupture its vacuole. (United States)

    Mellouk, Nora; Weiner, Allon; Aulner, Nathalie; Schmitt, Christine; Elbaum, Michael; Shorte, Spencer L; Danckaert, Anne; Enninga, Jost


    Shigella enters epithlial cells via internalization into a vacuole. Subsequent vacuolar membrane rupture allows bacterial escape into the cytosol for replication and cell-to-cell spread. Bacterial effectors such as IpgD, a PI(4,5)P2 phosphatase that generates PI(5)P and alters host actin, facilitate this internalization. Here, we identify host proteins involved in Shigella uptake and vacuolar membrane rupture by high-content siRNA screening and subsequently focus on Rab11, a constituent of the recycling compartment. Rab11-positive vesicles are recruited to the invasion site before vacuolar rupture, and Rab11 knockdown dramatically decreases vacuolar membrane rupture. Additionally, Rab11 recruitment is absent and vacuolar rupture is delayed in the ipgD mutant that does not dephosphorylate PI(4,5)P₂ into PI(5)P. Ultrastructural analyses of Rab11-positive vesicles further reveal that ipgD mutant-containing vacuoles become confined in actin structures that likely contribute to delayed vacular rupture. These findings provide insight into the underlying molecular mechanism of vacuole progression and rupture during Shigella invasion.

  11. Pectoralis major ruptures in professional American football players. (United States)

    Tarity, T David; Garrigues, Grant E; Ciccotti, Michael G; Zooker, Chad C; Cohen, Steven B; Frederick, Robert W; Williams, Gerald R; DeLuca, Peter F; Dodson, Christopher C


    Pectoralis major injuries are an infrequent shoulder injury that can result in pain, weakness, and deformity. These injuries may occur during the course of an athletic competition, including football. The purpose of this study was to determine the incidence of pectoralis major ruptures in professional football players and time lost from the sport following injury. We hypothesized that ruptures most frequently occur during bench-press strength training. The National Football League Injury Surveillance System was reviewed for all pectoralis major injuries in all players from 2000 to 2010. Details regarding injury setting, player demographics, method of treatment, and time lost were recorded. A total of 10 injuries-complete ruptures-were identified during this period. Five of the 10 were sustained in defensive players, generally while tackling. Nine occurred during game situations, and 1 occurred during practice. Specific data pertinent to the practice injury was not available. No rupture occurred during weight lifting. Eight ruptures were treated operatively, and 2 cases did not report the method of definitive treatment. The average days lost was 111 days (range, 42-189). The incidence was 0.004 pectoralis major ruptures during the 11-year study period. Pectoralis major injuries are uncommon while playing football. In the National Football League, these injuries primarily occur not during practice or while bench pressing but rather during games. When pectoralis major ruptures do occur, they are successfully treated operatively. Surgery may allow for return to full sports participation. IV, case series.

  12. Rupture of the uterus in Malawi and Tanzania. (United States)

    Armon, P J


    This paper describes the presenting features and possible etiology of 115 cases of rupture of the uterus occurring in Malawi and Tanzania. The series included 62 spontaneous ruptures, 24 traumatic ruptures, and 29 scar ruptures. The rupture was complete in 100 cases but the peritoneum was intact in 15. 72 cases involved obstructed labor and 29 occurred in women with previous cesarean sections. Only 22% of subjects were grand multiparae (7 or more pregnancies), and the average parity was 4.5. Classical symptoms and signs either did not occur or were late in appearing in most cases, and none of the women complained of a tearing or bursting sensation. 23 of the cases died during treatment. Sterilization is recommended in cases where the initial rupture extends into or is primarily situated in the upper segment of the uterus due to the probability of recurrence. Delays in reaching medical care and a lack of medical facilities contribute to the incidence of uterine rupture in developing countries. Careful screening for at-riskmothers and use of partograms to diagnose cephalopelvic disproportion during labor would diminish the occurrence of this complication, however. Also recommended is avoidance of unnecessary cesarean section procedures and extreme caution in the management of patients with uterine scars. The limitation of family size and improvements in maternal haalth education are further important preventive measures.

  13. Temporal and spatial rupture process of the great Kunlun Mountain Pass earthquake of November 14, 2001 from the GDSN long period waveform data

    Institute of Scientific and Technical Information of China (English)

    XU; Lisheng; CHEN; Yuntai


    The temporal and spatial rupture process of the 14 November 2001 Kunlun Mountain Pass earthquake (KMPE) is obtained by inverting the high signal-to-noise-ratio P-waveform data of vertical components of 20 stations with epicentral distances less than 90°, which are of Global Digital Seismogragh Network (GDSN). The inverted results indicate that the KMPE consists of 3 sub-events. The rupture of the first sub-event initiated at the instrumental epicenter (35.97°N,90.59°E) and then propagated both westwards and eastwards, extending 140 km westwards at the speed of 4.0 km/s and 80 km eastwards at the speed of 2.2 km/s, which appeared to be an asymmetrical bilateral rupture dominantly from east to west. This sub-event formed a 220-km-long fault. Fifty-two seconds after initiation of the first sub-event, at which time the first sub-event was not over but in its healing phase, the rupture of the second sub-event initiated 220 km west of the epicenter and propagated both westwards and eastwards, extending 50 km westwards at the speed of 2.2 km/s and 70 km eastwards at the speed of 5.8 km/s, which appeared to be an asymmetrical bilateral rupture dominantly from west to east. The secondsub-event formed a 120-km-long fault. The second sub-event fused with the first sub-event 140km west to the epicenter right 12 s after its initiation. Fifty-six seconds after initiation of the first sub-event, at which time the first sub-event was getting close to the end of its healing phase, the rupture of the third sub-event initiated 220 km east of the epicenter and propagated both westwards and eastwards, extending 140 km westwards at the speed of 4.0 km/s and 130 km eastwards at the speed of 3.7 km/s, which appeared to be nearly an bilateral rupture. This sub-event formed a 270-km-long fault. The third sub-event fused with the first sub-event 80 km east of the epicenter right 36 s after its initiation. Afterwards, the source process of the KMPE was dominated by the slip after fusion of

  14. Rupture process of the Ms 6.6 Superstition Hills, California, earthquake determined from strong-motion recordings: application of tomographic source inversion (United States)

    Frankel, Arthur D.; Wennerberg, Leif


    We analyze strong-motion recordings of the Ms 6.6 Superstition Hills earthquake to determine the timing, location, spatial extent, and rupture velocity of the subevents that produced the bulk of the high-frequency (0.5 to 4 Hz) seismic energy radiated by this shock. The earthquake can be characterized by three principal subevents, the largest ones occurring about 3 and 10 sec after initiation of rupture. Timing relationships between pulses on the seismograms indicate that the three subevents are located within 8 km of each other along the northern portion of the Superstition Hills fault. The two largest subevents display different directivity effects. We apply a tomographic source inversion to the integrated accelerograms to determine the slip acceleration on the fault as a function of time and distance, based on a one-dimensional fault model. The azimuthal distribution of amplitudes for the second subevent can be largely explained by a rupture that propagated about 2 km to the southeast along the Superstition Hills fault at a velocity about equal to the P-wave velocity. An alternative model with rupture propagating to the northeast along a conjugate fault plane can also account for the observed directivity of this subevent, but it is not supported by the aftershock distribution. The third subevent ruptured to the southeast along an 8-km long portion of the Superstition Hills fault at about the shear-wave velocity. This rupture propagation caused the relatively large accelerations and velocities observed in strong-motion records for stations southeast of the hypocenter. The long time intervals between the subevents and their relative proximity to each other indicate a very slow component to the rupture development. The southern half of the Superstition Hills fault did not generate significant high-frequency strong ground motion, although it showed substantial co-seismic surface displacement. The subevents are situated along the same northern portion of the fault

  15. Light Front Boson Model Propagation

    Institute of Scientific and Technical Information of China (English)

    Jorge Henrique Sales; Alfredo Takashi Suzuki


    stract The scope and aim of this work is to describe the two-body interaction mediated by a particle (either the scalar or the gauge boson) within the light-front formulation. To do this, first of all we point out the importance of propagators and Green functions in Quantum Mechanics. Then we project the covariant quantum propagator onto the light front time to get the propagator for scalar particles in these coordinates. This operator propagates the wave function from x+ = 0 to x+ > O. It corresponds to the definition of the time ordering operation in the light front time x+. We calculate the light-front Green's function for 2 interacting bosons propagating forward in x+. We also show how to write down the light front Green's function from the Feynman propagator and finally make a generalization to N bosons.

  16. Microscale characterization of rupture nucleation unravels precursors to faulting in rocks (United States)

    Renard, François; Cordonnier, Benoît; Kobchenko, Maya; Kandula, Neelima; Weiss, Jérôme; Zhu, Wenlu


    Precursory signals, manifestations of microscale damage that precedes dynamic faulting, are key to earthquake forecasting and risk mitigation. Detections of precursors have primarily relied on measurements performed using sensors installed at some distance away from the rupture area in both field and laboratory experiments. Direct observations of continuous microscale damage accumulated during fault nucleation and propagation are scarce. Using an X-ray transparent triaxial deformation apparatus, we show the first quantitative high resolution three-dimensional (3D) information about damage evolution of rocks undergoing brittle failure. The dynamic microtomography images documented a spectrum of damage characteristics and different fault growth patterns. The interplay between various deformation mechanisms can result in either a positive, negative, or constant net volume change. Consequently, changes in rock density and acoustic wave velocities before faulting are expected to vary in different tectonics settings, hence making failure forecasting intrinsically dependent on rock type at depth.

  17. Gauge engineering and propagators

    CERN Document Server

    Maas, Axel


    Beyond perturbation theory gauge-fixing becomes more involved due to the Gribov-Singer ambiguity: The appearance of additional gauge copies requires to define a procedure how to handle them. For the case of Landau gauge the structure and properties of these additional gauge copies will be investigated. Based on these properties gauge conditions are constructed to account for these gauge copies. The dependence of the propagators on the choice of these complete gauge-fixings will then be investigated using lattice gauge theory for Yang-Mills theory. It is found that the implications for the infrared, and to some extent mid-momentum behavior, can be substantial. In going beyond the Yang-Mills case it turns out that the influence of matter can generally not be neglected. This will be briefly discussed for various types of matter.

  18. Gauge engineering and propagators (United States)

    Maas, Axel


    Beyond perturbation theory gauge-fixing becomes more involved due to the Gribov-Singer ambiguity: The appearance of additional gauge copies requires to define a procedure how to handle them. For the case of Landau gauge the structure and properties of these additional gauge copies will be investigated. Based on these properties gauge conditions are constructed to account for these gauge copies. The dependence of the propagators on the choice of these complete gauge-fixings will then be investigated using lattice gauge theory for Yang-Mills theory. It is found that the implications for the infrared, and to some extent mid-momentum behavior, can be substantial. In going beyond the Yang-Mills case it turns out that the influence of matter can generally not be neglected. This will be briefly discussed for various types of matter.

  19. Counting Belief Propagation

    CERN Document Server

    Kersting, Kristian; Natarajan, Sriraam


    A major benefit of graphical models is that most knowledge is captured in the model structure. Many models, however, produce inference problems with a lot of symmetries not reflected in the graphical structure and hence not exploitable by efficient inference techniques such as belief propagation (BP). In this paper, we present a new and simple BP algorithm, called counting BP, that exploits such additional symmetries. Starting from a given factor graph, counting BP first constructs a compressed factor graph of clusternodes and clusterfactors, corresponding to sets of nodes and factors that are indistinguishable given the evidence. Then it runs a modified BP algorithm on the compressed graph that is equivalent to running BP on the original factor graph. Our experiments show that counting BP is applicable to a variety of important AI tasks such as (dynamic) relational models and boolean model counting, and that significant efficiency gains are obtainable, often by orders of magnitude.

  20. Propagators and path integrals

    Energy Technology Data Exchange (ETDEWEB)

    Holten, J.W. van


    Path-integral expressions for one-particle propagators in scalar and fermionic field theories are derived, for arbitrary mass. This establishes a direct connection between field theory and specific classical point-particle models. The role of world-line reparametrization invariance of the classical action and the implementation of the corresponding BRST-symmetry in the quantum theory are discussed. The presence of classical world-line supersymmetry is shown to lead to an unwanted doubling of states for massive spin-1/2 particles. The origin of this phenomenon is traced to a `hidden` topological fermionic excitation. A different formulation of the pseudo-classical mechanics using a bosonic representation of {gamma}{sub 5} is shown to remove these extra states at the expense of losing manifest supersymmetry. (orig.).

  1. Study of the Wheeler Propagator


    Bollini, C. G.; Rocca, M. C.


    We study the half advanced and half retarded Wheeler Green function and its relation to Feynman propagators. First for massless equation. Then, for Klein-Gordon equations with arbitrary mass parameters; real, imaginary or complex. In all cases the Wheeler propagator lacks an on-shell free propagation. The Wheeler function has support inside the light-cone (whatever the mass). The associated vacuum is symmetric with respect to annihilation and creation operators.

  2. Validity and Reliability of the Achilles Tendon Total Rupture Score

    DEFF Research Database (Denmark)

    Ganestam, Ann; Barfod, Kristoffer; Klit, Jakob


    The best treatment of acute Achilles tendon rupture remains debated. Patient-reported outcome measures have become cornerstones in treatment evaluations. The Achilles tendon total rupture score (ATRS) has been developed for this purpose but requires additional validation. The purpose of the present...... study was to validate a Danish translation of the ATRS. The ATRS was translated into Danish according to internationally adopted standards. Of 142 patients, 90 with previous rupture of the Achilles tendon participated in the validity study and 52 in the reliability study. The ATRS showed moderately...

  3. Rupture of the triceps tendon — A case series

    Institute of Scientific and Technical Information of China (English)

    Atin Jaiswal; Naiman Deep Kacchap; Yashwant Singh Tanwar; Devendra Kumar; Birendra Kumar


    Triceps rupture is the least common among all tendon injuries.The usual mechanism of injury is a fall on an outstretched hand,although direct contact injuries have also been reported to cause this injury.The diagnosis of acute triceps tendon rupture may be missed,which can result in prolonged disability and delayed operative management.We presented three cases of acute triceps tendon rupture each at different site showing the spectrum of injury to the muscle and mechanism of injury and management were also discussed.

  4. Endovascular Repair of a Ruptured Descending Thoracic Aortic Aneurysm (United States)

    DeFrain, Michael; Strickman, Neil E.; Ljubic, Branimir J.; Dougherty, Kathryn G.; Gregoric, Igor D.


    Endovascular aneurysm repair has considerable potential advantages over the surgical approach as a treatment for thoracic aortic rupture, in part because open surgical repair of ruptured thoracic aortic aneurysms is associated with high mortality and morbidity rates. We describe the successful endovascular deployment of stent-grafts to repair a contained rupture of a descending thoracic aortic aneurysm in an 86-year-old man whose comorbidities prohibited surgery. Two months after the procedure, magnetic resonance angiography showed a patent stent-graft, a patent left subclavian artery, and complete exclusion of the aneurysm. PMID:16878637

  5. Creep rupture behavior of welded Grade 91 steel

    Energy Technology Data Exchange (ETDEWEB)

    Shrestha, Triratna [Department of Chemical and Materials Engineering, University of Idaho, Moscow, ID 83844 (United States); Basirat, Mehdi [Department of Mechanical Engineering, University of Idaho, Moscow, ID 83844 (United States); Alsagabi, Sultan; Sittiho, Anumat [Department of Chemical and Materials Engineering, University of Idaho, Moscow, ID 83844 (United States); Charit, Indrajit, E-mail: [Department of Chemical and Materials Engineering, University of Idaho, Moscow, ID 83844 (United States); Potirniche, Gabriel P. [Department of Mechanical Engineering, University of Idaho, Moscow, ID 83844 (United States)


    Creep rupture behavior of fusion welded Grade 91 steel was studied in the temperature range of 600 – 700 °C and at stresses of 50–200 MPa. The creep data were analyzed in terms of the Monkman-Grant relation and Larson-Miller parameter. The creep damage tolerance factor was used to identify the origin of creep damage. The creep damage was identified as the void growth in combination with microstructural degradation. The fracture surface morphology of the ruptured specimens was studied by scanning electron microscopy and deformed microstructure examined by transmission electron microscopy, to further elucidate the rupture mechanisms.

  6. Bilateral patellar tendon rupture associated with statin use



    Patellar tendon rupture is an uncommon clinical presentation, which generally affects the under 40s who are active in sport. Bilateral rupture of both tendons is much rarer. It occurs most frequently in patients with predisposing factors such as corticosteroid use or systemic diseases. The authors present the case of a 56-year-old male on long-term statin therapy who sustained this injury following a fall on ice. He had no known risk factors for tendon rupture. Surgical treatment involved ten...

  7. Adductor longus tendon rupture mistaken for incarcerated inguinal hernia. (United States)

    Aerts, Bas R J; Plaisier, Peter W; Jakma, Tijs S C


    An incarcerated inguinal hernia is a common diagnosis, since the risk of an inguinal hernia incarcerating or strangulating is around 0.3-3%. An acute rupture of the adductor longus tendon is rarely seen and mostly affects (semi-) professional sportsmen. We present a case of a patient with an assumed incarcerated inguinal hernia which turned out to be a proximal adductor longus tendon rupture. If patients without a history of inguinal hernia present themselves with acute groin pain after suddenly exorotating the upper leg, a rupture of the adductor longus tendon should be considered. Both surgical and non-surgical treatment can be performed.

  8. Distal rupture of the adductor longus in a skier. (United States)

    Greditzer, Harry G; Nawabi, Danyal; Li, Angela Eh; Jawetz, Shari T

    Acute adductor longus ruptures occur infrequently and have been rarely described in the literature. Schlegel et al. reviewed a series of adductor longus tendon ruptures and found that all ruptured proximally. A 42-year-old man with right hip pain 3 weeks following a skiing injury underwent magnetic resonance imaging (MRI), which demonstrated a distal adductor longus avulsion. The diagnosis of acute adductor longus injury can be difficult on physical examination alone, but MRI can accurately depict the site of injury. Surgery may be indicated for a proximal avulsion, but a distal injury may heal with nonoperative treatment, as in our case. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. A ruptured large extraluminal ileal gastrointestinal stromal tumor causing hemoperitoneum

    Institute of Scientific and Technical Information of China (English)

    Shoji Hirasaki; Kohei Fujita; Minoru Matsubara; Hiromitsu Kanzaki; Hiromichi Yamane; Masato Okuda; Seiyuu Suzuki; Atsuko Shirakawa; Hideyuki Saeki


    We describe an 87-year-old woman with a large ileal gastrointestinal stromal tumor (GIST) causing hernoperitoneum. A CT scan demonstrated a large heterogeneous mass measuring about 13 crn × 11 cmin the pelvis and hemoperitoneurn, with a non-uniform enhancement pattern. The mass was diagnosed as a GIST originating from the gastrointestinal tract. She underwent an urgent laparotomy and an ileal GIST with a rupture was found 130 cm from the anal to the Treitz's ligament. Hernoperitoneum caused by ileal GIST rupture is a rare condition. Bleeding in the large tumor leading to rupture of the capsule might cause hemoperitoneurn in the present case.

  10. Design and Experimental Research on a New Pipe Rupture Valve

    Institute of Scientific and Technical Information of China (English)

    HU Guo-liang; XU Bing; YANG Hua-yong; ZHANG Yi-ding


    A new pipe rupture valve for hydraulic elevator is designed.Mathematical models established for the hydraulic elevator system are used in numefical simulations on the Simulink environment of Matlab kits.The effects of different viscous damping diameters.inlet pressures of pipe rupture valve.and elevator loads on the hydraulic elevator system's dynamic performance are analyzed.Expefimenml research is also carried out using a hydraulic elevator experiment rig.The numerical simulations accord with experimental results in general.Dynamic performance indexes are assessed by the EN812 standard.The results show that the newly designed pipe rupture valve meets the designing requirement for hydraulic elevators.

  11. Antibiotics for preterm rupture of membranes. (United States)

    Kenyon, Sara; Boulvain, Michel; Neilson, James P


    Premature birth carries substantial neonatal morbidity and mortality. Subclinical infection is associated with preterm rupture of membranes (PROM). Prophylactic maternal antibiotic therapy might lessen infectious morbidity and delay labour, but could suppress labour without treating underlying infection. To evaluate the immediate and long-term effects of administering antibiotics to women with PROM before 37 weeks, on maternal infectious morbidity, neonatal morbidity and mortality, and longer-term childhood development. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2013). Randomised controlled trials comparing antibiotic administration with placebo that reported clinically relevant outcomes were included as were trials of different antibiotics. Trials in which no placebo was used were included for the outcome of perinatal death alone. We extracted data from each report without blinding of either the results or the treatments that women received. We sought unpublished data from a number of authors. We included 22 trials, involving 6872 women and babies.The use of antibiotics following PROM is associated with statistically significant reductions in chorioamnionitis (average risk ratio (RR) 0.66, 95% confidence interval (CI) 0.46 to 0.96, and a reduction in the numbers of babies born within 48 hours (average RR 0.71, 95% CI 0.58 to 0.87) and seven days of randomisation (average RR 0.79, 95% CI 0.71 to 0.89). The following markers of neonatal morbidity were reduced: neonatal infection (RR 0.67, 95% CI 0.52 to 0.85), use of surfactant (RR 0.83, 95% CI 0.72 to 0.96), oxygen therapy (RR 0.88, 95% CI 0.81 to 0.96), and abnormal cerebral ultrasound scan prior to discharge from hospital (RR 0.81, 95% CI 0.68 to 0.98). Co-amoxiclav was associated with an increased risk of neonatal necrotising enterocolitis (RR 4.72, 95% CI 1.57 to 14.23).One study evaluated the children's health at seven years of age (ORACLE Children Study) and found

  12. Fatigue crack propagation in self-assembling nanocomposites (United States)

    Klingler, Andreas; Wetzel, Bernd


    Self-assembling block-copolymers allow the easy manufacturing of nanocomposites due to the thermodynamically driven in situ formation of nanosized phases in thermosetting resins during the curing process. Complex mechanical dispersion processes can be avoided. The current study investigates the effect of a block-copolymer on the fatigue crack propagation resistance of a cycloaliphatic amine cured epoxy resin. It was found that a small amount of MAM triblock-copolymer significantly increases the resistance to fatigue crack propagation of epoxy. Crack growth rate and the Paris law exponent for fatigue-crack growth were considerably reduced from m=15.5 of the neat epoxy to m=8.1 of the nanocomposite. To identify the related reinforcing and fracture mechanisms structural analyses of the fractured surfaces were performed by scanning electron microscope. Characteristic features were identified to be deformation, debonding and fracture of the nano-phases as well as crack pinning. However, the highest resistance against fatigue crack propagation was achieved in a bi-continuous microstructure that consisted of an epoxy-rich phase with embedded submicron sized MAM inclusions, and which was surrounded by a block-copolymer-rich phase that showed rupture and plastic deformation.

  13. Spontaneous Ureteral Rupture Diagnosis and Treatment

    Directory of Open Access Journals (Sweden)

    E. Pampana


    Full Text Available Rupture of the urinary collecting system associated with perinephric or retroperitoneal extravasation of the urine is an unusual condition and it is commonly associated with renal obstructing disease. Perforation could occur at any level from the calix to the bladder but it is usually seen at the fornices and upper ureter. It may lead to several serious consequences including urinoma, abscess formation, urosepsis, infection, and subsequent irreversible renal impairment. We report a case of a 69-year-old woman who presented at the emergency department of our institution with severe abdominal pain. Due to symptomatology worsening, complete laboratory evaluation was performed and the patient underwent abdominal contrast enhanced computed tomography (CT evaluation which showed contrast agent extravasation outside the excretory system without any evidence of renal calculi at basal acquisition. It was decided to perform a double-J stent placement which was followed by complete healing of the ureter and its removal was performed 8 weeks later. Diagnosis and therapeutic approaches are discussed.

  14. Thermobarometry of metamorphosed pseudotachylyte and associated mylonite: Constraints on dynamic Co-seismic rupture depth attending Caledonian extension, North Norway (United States)

    Leib, S. E.; Moecher, D. P.; Steltenpohl, M. G.; Andresen, Arild


    The exhumed post-Caledonian Eidsfjord and Fiskfjord extensional shear zones of northern Norway exhibit evidence of coseismic rupture propagating into the ductile crust as evidenced by the presence of mylonitic and metamorphosed pseudotachylyte. Geothermobarometric calculations on garnet-bearing mineral assemblages in mylonitic gneisses associated with mylonitic pseudotachylyte and in metamorphosed pseudotachylyte permit determination of the depth and ambient temperature of seismogenic low-angle ductile extension. Average pressures from Eidsfjord (570 ± 115 MPa at ca. 650 °C) and Fiskfjord (1120 ± 220 MPa at ca. 650 °C) correspond to faulting depths of 21 ± 4 km and 41 ± 9 km, respectively. The Fiskfjord results agree with previous thermobarometric calculations on mylonitic Cpx + Grt-bearing pseudotachylyte at Fiskfjord. The calculated depths are 5-25 km below the depth of the standard seismogenic zone. These results demonstrate that low angle normal faults may cut through a large portion of continental crust. This occurrence of mylonitic pseudotachylyte in an extensional crustal setting is most easily explained by dynamic downward rupture into the ductile regime and/or unusually high shear stresses to account for coseismic rupture at such depths, implying a direct connection with a seismogenic normal fault in the upper crust.

  15. Coronary spasm, a pathogenic trigger of vulnerable plaque rupture

    Institute of Scientific and Technical Information of China (English)

    WANG Li-xin; L(U) Shu-zheng; ZHANG Wei-jun; SONG Xian-tao; CHEN Hui; ZHANG Li-jie


    Objective This coronary artery spasm review aimed to explore the most possible pathogenic trigger mechanism of vulnerable plaque rupture.Data sources Data used in this coronary artery spasm review were mainly from Medline and Pubmed in English.Study selection These reports from major review on coronary artery spasm.and these research included coronary artery conception,pathogenesis of spasm,mechanisms of plaque rupture,epidemiological evidence,clinical manifestation and the relationship between coronary artery spasm and vulnerable plaque rupture.Results Coronary artery spasm is somehow related to the presence of atherosclerotic intima disease in the coronary artery.However,chronic low-grade inflammation causes coronary vessel smooth muscle cell hypersensitivity,which can directely cause coronary artery spasm.Myocardial infarction and sudden cardiac death may be initiated by a sudden intense localized contraction of coronary artery smooth muscle.Conclusion Coronary artery spasm may be one trigger that can initiate and exacerbate vulnerable plaque rupture.

  16. Uroperitoneum attributable to ruptured urachus in a yearling bull. (United States)

    Baxter, G M; Zamos, D T; Mueller, P O


    Ruptured urachus was found to result in uroperitoneum in a yearling Beefmaster bull. The uroperitoneum was initially believed to be attributable to ruptured bladder secondary to urolithiasis; however, catheter decompression of the bladder through an ischiatic urethrotomy did not resolve the uroperitoneum. The persistent urachus was diagnosed and removed through caudal right flank laparotomy with the bull standing. The urachus was attached to the umbilicus, communicated with the lumen of the bladder, and had a mucosal lining. Ruptured urachus is an unusual cause of uroperitoneum, but can cause clinical signs identical to those of ruptured bladder. Persistent urachus is a congenital abnormality in many species, but may be hereditary in Beefmaster cattle. In addition, the bull in this report developed hyperkalemia, which is considered an unusual finding in cattle with uroperitoneum.

  17. A rare knee extensor mechanism injury: Vastus intermedius tendon rupture

    Directory of Open Access Journals (Sweden)

    Engin Cetinkaya


    Conclusion: We report the first case of isolated rupture of the vastus intermedius tendon in the literature and we claim that disorder may be succesfully treated with conservative treatment and adequate physiotheraphy.

  18. A case report of left ventricular wall rupture

    Directory of Open Access Journals (Sweden)

    Kordovani H


    Full Text Available Cardiac rupture, particularly rupture of the left ventricular wall, has a very high mortality rate. In this occasion, even if injured patients being alive when carried to the hospital, many of them will die due to following possible reasons: severe bleeding, cardiac tamponade, wasting time for routine and usual diagnostic procedures or transferring the injured to other hospital equipped for cardiac surgery. The only way to avoid these dangerous hazards is prompt thoracotomy and repair of the wound, which must be done in any surgical ward available. We report a case of cardiact rupture due to penetrating injury caused by a slender sharp object, passing through the heart anteroposteriorly. The patient was successfully rescued. This report indicates that in hospital, where no facility for cardiac surgery is available, this kind of emergency surgery for cardiac rupture is very indicative and may save the life of injured patient.

  19. Functional rehabilitation of patients with acute Achilles tendon rupture

    DEFF Research Database (Denmark)

    Mark-Christensen, Troels; Troelsen, Anders; Kallemose, Thomas


    PURPOSE: The optimal treatment for acute Achilles tendon rupture (ATR) is continuously debated. Recent studies have proposed that the choice of either operative or non-operative treatment may not be as important as rehabilitation, suggesting that functional rehabilitation should be preferred over......, CINAHL, Cochrane Library and PEDro using the search terms: "Achilles tendon," "rupture," "mobilization" and "immobilization". Seven RCTs involving 427 participants were eligible for inclusion, with a total of 211 participants treated with functional rehabilitation and 216 treated with immobilization....... CONCLUSION: Functional rehabilitation after acute Achilles tendon rupture does not increase the rate of re-rupture or other complications. A trend toward earlier return to work and sport, and increased patient satisfaction was found when functional rehabilitation was used. The present literature is of low...

  20. Automatic rupture of unused intraport catheter. Case report. (United States)

    Pappas, Paris; Dalianis, Nikolaos; Filippou, Dimitrios K; Condiis, Nicolas; Rizos, Spiros; Skandalakis, Panagiotis


    Totally Implantable Central Venous Access Devices (Intraports) are commonly used in cancer patients to administer chemotherapy or parenteral nutrition. These devices are placed by Seldinger technique. We report an unusual case of intraport catheter rupture before the use of the device. The ruptured part of the catheter migrated into the left pulmonary vein via right ventricle. The ruptured part was removed by means of interventional radiology before causing any problems to the patient. All the reported ruptures of port catheters refer to port devices that had been used to administer chemotherapy, fluids, or parenteral nutrition. The unique feature of this case is that the catheter had not been used at all. It is of great interest also the removal of the broken part from the pulmonary vein.

  1. Plantar fascia rupture in a professional soccer player. (United States)

    Suzue, Naoto; Iwame, Toshiyuki; Kato, Kenji; Takao, Shoichiro; Tateishi, Tomohiko; Takeda, Yoshitsugu; Hamada, Daisuke; Goto, Tomohiro; Takata, Yoichiro; Matsuura, Tetsuya; Sairyo, Koichi


    We report the case of a 29-year-old male professional soccer player who presented with symptoms of plantar fasciitis. His symptoms occurred with no remarkable triggers and gradually worsened despite conservative treatments including taping, use of insoles, and physical therapy. Local corticosteroid injection was given twice as a further intervention, but his plantar fascia partially ruptured 49 days after the second injection. He was treated conservatively with platelet-rich plasma, and magnetic resonance imaging showed regenerative change of the ruptured fascia. Five months after the rupture, he returned to his original level of training. If professional athletes find it difficult to refrain from athletic activity, as in the present case, the risk of rupture due to corticosteroid injection should not be overlooked.

  2. Endobronchial Cartilage Rupture: A Rare Cause of Lobar Collapse (United States)

    Siddiqui, Nauman; Javaid, Toseef


    Endobronchial cartilage rupture is a rare clinical condition, which can present in patients with severe emphysema with sudden onset shortness of breath. We present a case of a 62-year-old male who presented to our emergency department with sudden onset shortness of breath. Chest X-ray showed lung hyperinflation and a right lung field vague small density. Chest Computed Tomography confirmed the presence of right middle lobe collapse. Bronchoscopy revealed partial right middle lobe atelectasis and an endobronchial cartilage rupture. Endobronchial cartilage rupture is a rare condition that can present as sudden onset shortness of breath due to lobar collapse in patients with emphysema and can be triggered by cough. Bronchoscopic findings include finding a collapsed lung lobe and a visible ruptured endobronchial cartilage. A high index of suspicion, chest imaging, and early bronchoscopy can aid in the diagnosis and help prevent complications. PMID:27525149

  3. Ruptured chordae tendineae in acromegaly. An autopsy case. (United States)

    Kaku, T; Nakashima, Y; Ichiyasu, H; Soejima, M; Baba, K; Kuroiwa, A


    A 57-year-old woman with acromegaly associated with mitral chordal rupture is reported. She was noted to have abnormal development in the size of her hands and feet in childhood. She occasionally suffered from shortness of breath on exertion and nocturnal dyspnea for several years, and was diagnosed and treated as having congestive heart failure due to valvular heart disease. On admission to our hospital, chordal rupture was suspected on the basis of M-mode and two-dimensional echocardiography. Seven years after discharge, she died of congestive heart failure. On autopsy, the heart weight and ventricular wall thickness were increased. Rupture of the posterior chordae was confirmed, but evidence of an old myocardial infarction was not found. There was severe interstitial fibrosis in the left ventricular wall. A possible etiology of the chordal rupture in this case was thought to be the excessive stretching caused by the disproportional visceromegaly of the heart.

  4. Uterine rupture an obstetrics catastrophy; incidence, risk factors ...

    African Journals Online (AJOL)

    Uterine rupture an obstetrics catastrophy; incidence, risk factors, management ... at Abubakar Tafawa Balewa University Teaching Hospital Bauchi Nigeria. ... is 0.35% and the common risk factors include high parity, exposure to oxytocin in ...

  5. An unusual case of cardiac tamponade: ruptured subaortic diverticulum. (United States)

    Salemi, Arash; Lee, Ben; Ivascu, Natalia; Webber, Geoffrey; Paul, Subroto


    Cardiac diverticula are rare congenital anomalies found as outpouchings from various chambers of the heart. We present a case of a diverticulum arising from the membranous septum with free rupture into the pericardial space and tamponade.

  6. Premature rupture of membranes at term: immediate induction of ...

    African Journals Online (AJOL)

    Premature rupture of membranes at term: immediate induction of labor versus expectant ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... Methods: One hundred and fifty two women with PROM at term were ...

  7. Asymptomatic spontaneous rupture of suprasellar dermoid cyst : a case report.

    Directory of Open Access Journals (Sweden)

    Venkatesh S


    Full Text Available Suprasellar dermoid cysts are uncommon intracranial lesions. CT and MRI findings in a rare case of asymptomatic rupture of suprasellar dermoid cyst with subarachnoid dissemination is described.


    Institute of Scientific and Technical Information of China (English)

    管珩; 郑月宏; 李拥军; 刘昌伟; 刘暴; 叶炜


    Objective. To describe our surgical experience on rupture of abdominal aortic aneurysm .Methods. Two cases of ruptured aortic aneurysms with severe complication were analyzed. Aorta re-construction procedures were performed using bifurcated e-PTFE grafts during emergency operation. Diag-nosis, preoperative resuscitation, emergency surgical intervention, and postoperative complications of thesepatients were summarized and discussed.Results. Rupture of aortic aneurysm in both patients presented as a huge retroperitoneum haematomaby computed tomography scan. They were successfully saved by prompt body fluid compensation, emer-gency procedure, intraoperative resuscitation, and postoperative intensive care.Conclusions. Correct diagnosis, prompt surgical management, immediate intraoperative proximal aortaclamping during procedure, and effective management of postoperative complications were the key pointsto successful treatment of ruptured aortic aneurysm.

  9. Propagation of Ion Acoustic Perturbations

    DEFF Research Database (Denmark)

    Pécseli, Hans


    Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered.......Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered....

  10. Ultrasound Diagnosis of Bilateral Quadriceps Tendon Rupture After Statin Use

    Directory of Open Access Journals (Sweden)

    Nesselroade, Ryan D


    Full Text Available Simultaneous bilateral quadriceps tendon rupture is a rare injury. We report the case of bilateral quadriceps tendon rupture sustained with minimal force while refereeing a football game. The injury was suspected to be associated with statin use as the patient had no other identifiable risk factors.The diagnosis was confirmed using bedside ultrasound. [West J Emerg Med. 2010; 11(4:306-309.

  11. Isolated duodenal rupture due to blunt abdominal trauma

    Directory of Open Access Journals (Sweden)

    Celik Atilla


    Full Text Available Duodenal rupture following blunt abdominal trauma is rare and it usually seen with other abdominal organ injuries. It represents approximately 2% to 20% of patients with blunt abdominal injury and often occurs after blows to the upper abdomen, or abdominal compression from high-riding seat belts. Two cases of blunt duodenal rupture successfully treated surgically, are presented with their preoperative diagnosis and final out comes.

  12. Blunt cardiac rupture in patient with liver laceration

    Institute of Scientific and Technical Information of China (English)

    王文林; 曾伟生; 蒋仁超


    The early diagnosis of cardiac rupture is one of the key factors for a successful outcome. However, the accurate diagnosis is often difficult in the early stage of injury, especially when some obvious severe wounds are found in other regions of the body,1,2 for they are easy to disguise the symptom of the heart. We report a case with cardiac rupture and liver trauma caused by traffic accident.

  13. Ultrasound, CT and MRI of ruptured and disseminated hydatid cysts

    Energy Technology Data Exchange (ETDEWEB)

    Sinner, W.N. von (King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia). Department of Radiology)

    Three cases of echinococcus granulosus with rupture of hydatid cysts and widespread abdominal, pelvic of pleural dissemination are described. Ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) allowed recognition of ruptured hydatid cysts. This assisted to come to an appropriate therapy and exclusion or confirmation of hydatid cysts elsewhere in the body. Ultrasound, CT and MRI are also important for follow-up, evaluation of therapeutic response and/or early diagnosis of recurrence. (author). 22 refs.; 3 figs.

  14. Complications of plantar fascia rupture associated with corticosteroid injection. (United States)

    Acevedo, J I; Beskin, J L


    From 1992 to 1995, 765 patients with a clinical diagnosis of plantar fasciitis were evaluated by one of the authors. Fifty-one patients were diagnosed with plantar fascia rupture, and 44 of these ruptures were associated with corticosteroid injection. The authors injected 122 of the 765 patients, resulting in 12 of the 44 plantar fascia ruptures. Subjective and objective evaluations were conducted through chart and radiographic review. Thirty-nine of these patients were evaluated at an average 27-month follow-up. Thirty patients (68%) reported a sudden onset of tearing at the heel, and 14 (32%) had a gradual onset of symptoms. In most cases the original heel pain was relieved by rupture. However, these patients subsequently developed new problems including longitudinal arch strain, lateral and dorsal midfoot strain, lateral plantar nerve dysfunction, stress fracture, hammertoe deformity, swelling, and/or antalgia. All patients exhibited diminished tension of the plantar fascia upon examination by the stretch test. Comparison of calcaneal pitch angles in the affected and uninvolved foot showed a statistically significant difference of 3.7 degrees (P = 0.0001). Treatment included NSAIDs, rest or cross-training, stretching, orthotics, and boot-brace immobilization. At an average 27-month follow-up, 50% had good/excellent scores and 50% had fair/poor scores. Recovery time was varied. Ten feet were asymptomatic by 6 months post rupture, four feet by 12 months post rupture, and 26 feet remained symptomatic 1 year post rupture. Our findings demonstrate that plantar fascia rupture after corticosteroid injection may result in long-term sequelae that are difficult to resolve.

  15. Multiple barriers in forced rupture of protein complexes

    CERN Document Server

    Hyeon, Changbong


    Curvatures in the most probable rupture force ($f^*$) versus log-loading rate ($\\log{r_f}$) observed in dynamic force spectroscopy (DFS) on biomolecular complexes are interpreted using a one-dimensional free energy profile with multiple barriers or a single barrier with force-dependent transition state. Here, we provide a criterion to select one scenario over another. If the rupture dynamics occurs by crossing a single barrier in a physical free energy profile describing unbinding, the exponent $\

  16. Rupture of benign thyroid tumors after radio-frequency ablation. (United States)

    Shin, J H; Jung, S L; Baek, J H; Kim, J-H


    Rupture of benign thyroid tumors after RFA is very rare. We experienced 6 cases in 4 institutions. All patients presented with abrupt neck swelling and pain between 9 and 60 days after RFA. Imaging and clinical findings of the ruptured tumors were anterior subcapsular location, mixed composition, large size, and repeated ablations. Conservative treatment was sufficient in 3 cases, whereas surgical management was required in 3.

  17. Preterm Delivery in the Setting of Left Calyceal Rupture



    Spontaneous rupture of the renal collecting system is a rare but serious complication of pregnancy. We report a case of nontraumatic left renal calyceal rupture in a pregnancy which ultimately progressed to preterm delivery. A 29-year-old primigravida with a remote history of urolithiasis presented with left flank pain, suprapubic pain, and signs of preterm labor at 33 weeks of gestation. The patient was believed to have urolithiasis, although initial renal ultrasound failed to demonstrate de...

  18. Supraspinatus rupture at the musculotendinous junction in a young woman


    Benazzo, Francesco; MARULLO, MATTEO; Pietrobono, Luigi


    The vast majority of rotator cuff tears occur within the tendon or as an avulsion from the greater tuberosity. Supraspinatus injury at the musculotendinous junction is a very uncommon event. We describe a case of supraspinatus rupture at the musculotendinous junction, with successful conservative treatment. It occurred in a 23-year-old woman, the youngest patient with this uncommon type of injury. To our knowledge, this is the first case of rupture of the supraspinatus muscle at the musculote...

  19. Emergency endovascular repair of ruptured visceral artery aneurysms

    Directory of Open Access Journals (Sweden)

    Tang Tjun


    Full Text Available Abstract Background Visceral artery aneurysms although rare, have very high mortality if they rupture. Case presentation An interesting case of a bleeding inferior pancreaticduodenal artery aneurysm is reported in a young patient who presented with hypovolemic shock while being treated in the hospital after undergoing total knee replacement. Endovascular embolization was successfully employed to treat this patient, with early hospital discharge. Conclusion Prompt diagnosis and endovascular management of ruptured visceral aneuryms can decrease the associated mortality and morbidity.

  20. Spontaneous splenic rupture: A rare presentation of dengue fever

    Directory of Open Access Journals (Sweden)

    Mainak Mukhopadhyay


    Full Text Available Spontaneous rupture of the spleen with hemoperitoneum is a very rare, but serious manifestation of dengue fever (DF. We report a case of a young female who was presented with atraumatic abdominal pain, hypovolemic shock, anemia, ascites and hepatosplenomegaly with a recent history of a febrile illness. Subsequent investigations proved the presence of hemoperitoneum with spontaneous splenic rupture with seropositivity for DF. Early diagnosis and conservative management in this case resulted in a favorable outcome.

  1. Source Rupture Process and Near-Fault Ground Motions of the 2016 Kumamoto Earthquake Sequence Estimated from Strong Motion Data (United States)

    Asano, K.; Iwata, T.


    The 2016 Kumamoto earthquake sequence started with an MJMA 6.5 foreshock on April 14, 2016 occurring along the northern part of the Hinagu fault, central Kyushu, Japan, and the MJMA 7.3 mainshock occurred just 28 h after the foreshock. Both events brought severe ground motions to the near-source region. We analyzed the kinematic source rupture processes of the foreshock and mainshock by the multiple time window linear waveform inversion using strong motion data (e.g., Hartzell and Heaton, 1983). The foreshock (Mw 6.1) was characterized by right-lateral strike-slip occurring on a nearly vertical fault plane along the northern part of the Hinagu fault, and it had two large-slip areas: one near the hypocenter and another at a shallow depth. These two large-slip areas mainly contribute ground motions in the near-source area. For the analysis of the mainshock, we assumed a fault geometry changing strike and dip angles along the Hinagu and Futagawa faults in accordance with the surface ruptures mapped by emergency field surveys (Kumahara et al., 2016). We assigned point sources densely with an interval of 0.2 km on the assumed fault planes in order to reproduce appropriately near-fault ground motions, and estimated spatiotemporal slip history, which was discretized with an interval of 1.8 km on the fault planes. The estimated source model reveals that the rupture of the mainshock started at a northwest-dipping fault plane along the Hinagu fault, which is close to the vertical fault plane of the foreshock, and almost continuously propagated across the junction of the Hinagu and Futagawa faults. Then the rupture propagated northeastward along the Futagawa fault, and stopped to rupture in the western part of the Aso caldera. The significant slip with 3-5 m were observed on the Futagawa fault, and shallowest part has slip ranging from 1 to 2 m. We also tried to reproduce ground motions observed at some near-fault strong motion stations, which recorded significant coseismic

  2. Propagation Engineering in Wireless Communications

    CERN Document Server

    Ghasemi, Abdollah; Ghasemi, Farshid


    Wireless communications has seen explosive growth in recent decades, in a realm that is both broad and rapidly expanding to include satellite services, navigational aids, remote sensing, telemetering, audio and video broadcasting, high-speed data communications, mobile radio systems and much more. Propagation Engineering in Wireless Communications deals with the basic principles of radiowaves propagation for frequency bands used in radio-communications, offering descriptions of new achievements and newly developed propagation models. The book bridges the gap between theoretical calculations and approaches, and applied procedures needed for advanced radio links design. The primary objective of this two-volume set is to demonstrate the fundamentals, and to introduce propagation phenomena and mechanisms that engineers are likely to encounter in the design and evaluation of radio links of a given type and operating frequency. Volume one covers basic principles, along with tropospheric and ionospheric propagation,...

  3. View-based Propagator Derivation

    CERN Document Server

    Schulte, Christian


    When implementing a propagator for a constraint, one must decide about variants: When implementing min, should one also implement max? Should one implement linear constraints both with unit and non-unit coefficients? Constraint variants are ubiquitous: implementing them requires considerable (if not prohibitive) effort and decreases maintainability, but will deliver better performance than resorting to constraint decomposition. This paper shows how to use views to derive perfect propagator variants. A model for views and derived propagators is introduced. Derived propagators are proved to be indeed perfect in that they inherit essential properties such as correctness and domain and bounds consistency. Techniques for systematically deriving propagators such as transformation, generalization, specialization, and type conversion are developed. The paper introduces an implementation architecture for views that is independent of the underlying constraint programming system. A detailed evaluation of views implement...

  4. Directed HK propagator (United States)

    Kocia, Lucas; Heller, Eric J.


    We offer a more formal justification for the successes of our recently communicated "directed Heller-Herman-Kluk-Kay" (DHK) time propagator by examining its performance in one-dimensional bound systems which exhibit at least quasi-periodic motion. DHK is distinguished by its single one-dimensional integral—a vast simplification over the usual 2N-dimensional integral in full Heller-Herman-Kluk-Kay (for an N-dimensional system). We find that DHK accurately captures particular coherent state autocorrelations when its single integral is chosen to lie along these states' fastest growing manifold, as long as it is not perpendicular to their action gradient. Moreover, the larger the action gradient, the better DHK will perform. We numerically examine DHK's accuracy in a one-dimensional quartic oscillator and illustrate that these conditions are frequently satisfied such that the method performs well. This lends some explanation for why DHK frequently seems to work so well and suggests that it may be applicable to systems exhibiting quite strong anharmonicity.

  5. Range Information Propagation Transform

    Institute of Scientific and Technical Information of China (English)

    陈向荣; 朱志刚; 等


    A novel method of model-based object recognition is presented in this paper.Its novelty stems from the fact that the gray level image captured by a camera is merged with sparse range information in an active manner.By using a projective transform, which is determined by the sparse range data,festures(e.g.edge points)related to a single planar surface patch of figure in the scene can be assignew with their corresponding range values respectively.As a result,the shape of the very planar patch or figure can be recovered and various kinds of description in the Euclidean space can be calculated.Based on these descriptions values,the hypothesis about the identification of the object and its pose in space can be obtained with a high probability of success,and a high efficiency of hypothesis-verification process can be expected.Another advantage of this method is that the edge detection process can be navigated to the proper location hinted by the sparse range image.In consequence edge features can be extracted even in the regions with low contrast.In this paper the principle of range information propagation transform(RIPT)is explained,and some implementation issues,such as the algorithms using calibrated or uncalibrated gray level image for object recognition,are discussed.The preliminary experimental results are presented to indicate the effectiveness and efficiency of the proposed method.

  6. Sexual intercourse and cerebral aneurysmal rupture: potential mechanisms and precipitants. (United States)

    Reynolds, Matthew R; Willie, Jon T; Zipfel, Gregory J; Dacey, Ralph G


    Aneurysmal subarachnoid hemorrhage (SAH) is a significant cause of death in young and middle-aged individuals and causes tremendous morbidity in affected patients. Despite the identification of various risk factors, the series of events leading to the formation, growth, and rupture of intracranial aneurysms is poorly understood. Cerebral aneurysm rupture has been associated with sexual intercourse and other forms of physical exercise. In fact, multiple case series reported that coitus was the immediate preceding activity in 3.8-14.5% of patients suffering from aneurysmal SAH. This may be related to the large elevations in mean arterial blood pressure that occur in both males and females during sexual intercourse (130-175 and 125-160 mm Hg, respectively). While coitus and physical exercise share important physiological similarities, each may differentially affect the probability that a preformed aneurysm will rupture. In this literature review and synthesis, the authors analyze the physiological human response to sexual intercourse in an effort to delineate those factors that may precipitate aneurysmal rupture. The authors' analysis is based on the original data collected by Masters and Johnson. To the authors' knowledge, this is the first review to address the link between sexual intercourse and intracranial aneurysmal rupture. While actual measurements of the physiological variables relevant to SAH were not performed in this article, the authors make reasonable assumptions based on the available data to help elucidate the mechanism of sexually induced aneurysmal rupture.

  7. Magnetic resonance imaging and computed radiography in Achilles tendon rupture

    Energy Technology Data Exchange (ETDEWEB)

    Korenaga, Tateo; Hachiya, Junichi; Miyasaka, Yasuo and others


    Magnetic Resonance Imaging (MRI) and Computed Radiography (CR) were performed in 15 patients with complete Achilles tendon rupture who were treated conservatively without surgery. MRI was obtained using Toshiba MRT 50 A superconductive machine, operaing at 0.5 Tesla. CR was performed by CR-101, Fuji Medical System. In fresh cases, ruptured tendons showed intermediate signal intensity on T1-weighted images and high intensity on T2-weighted images. Thickening of the tendon was observed in all cases except in very acute stage. Configuration of thickend tendons tends to be dumbbell shape in subacute stage and fusiform in chronic stage of more than six months after the initial trauma. In cases which showed high signal intensity at the ruptured area both on T1 and T2 weighted images, migration of fat into the sapces between the ruptured tendons was considered to be the major source of increased signal intensity. Computed radiography showed thickening of the tendon, blurring of anterior margin of the tendon, and decreased translucency of pre-Achilles fat pad. However, MRI better demonstrated the details of ruptured tendons when compared to CR, and thought to be an usefull way of following up the healing process of the ruptured tendon to facilitate more reasonable judgement of the time of removing plaster casts and stating exercise.

  8. Stochastic Earthquake Rupture Modeling Using Nonparametric Co-Regionalization (United States)

    Lee, Kyungbook; Song, Seok Goo


    Accurate predictions of the intensity and variability of ground motions are essential in simulation-based seismic hazard assessment. Advanced simulation-based ground motion prediction methods have been proposed to complement the empirical approach, which suffers from the lack of observed ground motion data, especially in the near-source region for large events. It is important to quantify the variability of the earthquake rupture process for future events and to produce a number of rupture scenario models to capture the variability in simulation-based ground motion predictions. In this study, we improved the previously developed stochastic earthquake rupture modeling method by applying the nonparametric co-regionalization, which was proposed in geostatistics, to the correlation models estimated from dynamically derived earthquake rupture models. The nonparametric approach adopted in this study is computationally efficient and, therefore, enables us to simulate numerous rupture scenarios, including large events (M > 7.0). It also gives us an opportunity to check the shape of true input correlation models in stochastic modeling after being deformed for permissibility. We expect that this type of modeling will improve our ability to simulate a wide range of rupture scenario models and thereby predict ground motions and perform seismic hazard assessment more accurately.

  9. Venous rupture during percutaneous treatment of hemodialysis fistulas and grafts. (United States)

    Bittl, John A


    The aim of this study was to analyze the risk and consequences of venous rupture during angioplasty of malfunctioning hemodialysis grafts and fistulas. Venous stenoses in the outflow limb of hemodialysis accesses often require ultra-high balloon pressure for optimal dilatation. Baseline characteristics and outcomes were analyzed for a consecutive series of patients treated between 1999 and 2008. Venous rupture or perforation occurred in 11 of 1242 (0.9%) procedures. No patient with a rupture or perforation died or required emergency or urgent surgical repair. Two of 11 patients (18.2%) required transfusions, 8 of 11 patients (72.7%) required stenting, and 6 of 8 (75.0%) who needed stenting received covered stents to achieve hemostasis. Rupture led to access thrombosis within 30 days in 9 of 11 cases (82%). Multivariable logistical regression analysis suggested that using a balloon catheter more than 2 mm larger than the diameter of the hemodialysis access or using peripheral cutting balloons increased the risk of rupture or perforation. Rupture or perforation is a rare complication of treatment of malfunctioning hemodialysis grafts and fistulas. The complication may be managed with nonsurgical methods and might be avoided by optimal balloon selection and sizing.

  10. Ground-motion signature of dynamic ruptures on rough faults (United States)

    Mai, P. Martin; Galis, Martin; Thingbaijam, Kiran K. S.; Vyas, Jagdish C.


    Natural earthquakes occur on faults characterized by large-scale segmentation and small-scale roughness. This multi-scale geometrical complexity controls the dynamic rupture process, and hence strongly affects the radiated seismic waves and near-field shaking. For a fault system with given segmentation, the question arises what are the conditions for producing large-magnitude multi-segment ruptures, as opposed to smaller single-segment events. Similarly, for variable degrees of roughness, ruptures may be arrested prematurely or may break the entire fault. In addition, fault roughness induces rupture incoherence that determines the level of high-frequency radiation. Using HPC-enabled dynamic-rupture simulations, we generate physically self-consistent rough-fault earthquake scenarios (M~6.8) and their associated near-source seismic radiation. Because these computations are too expensive to be conducted routinely for simulation-based seismic hazard assessment, we thrive to develop an effective pseudo-dynamic source characterization that produces (almost) the same ground-motion characteristics. Therefore, we examine how variable degrees of fault roughness affect rupture properties and the seismic wavefield, and develop a planar-fault kinematic source representation that emulates the observed dynamic behaviour. We propose an effective workflow for improved pseudo-dynamic source modelling that incorporates rough-fault effects and its associated high-frequency radiation in broadband ground-motion computation for simulation-based seismic hazard assessment.

  11. Reduction in the occurrence of uterine rupture in Central India. (United States)

    Chhabra, S; Bhagwat, N; Chakravorty, Anupama


    This study was carried out in the Department of Obstetrics and Gynaecology of the Mahatma Gandhi Institute of Medical Sciences, Sevagram in Central India. In the 12 years between 1989 and 2000 a total of 16 cases of ruptured uterus were managed, the incidence of rupture of the pregnant uterus being 0.62 per 1000 births. One-quarter of the cases occurred between 1983 and 1988. No teenager or elderly woman (over 40) or grandmultipara sustained a uterine rupture. Four women had a rupture of a previous scar. In five rupture had occurred in association with malpresentations, one was a case of hydrocephalus, two had a morbidly adherent placenta praevia and four had a normal presentation, with lack of progress in labour. Two of these 16 women had twins. One had come with a retained second twin with transverse lie and the other was a booked case with multiple problems, including a previous caesarean section, present twin pregnancy and placenta praevia accreta and she died. This was the only maternal death. Perinatal mortality was 77.77% compared to 5.88% maternal and 100% perinatal mortality in the cases reported previously between 83 and 88, from the same institution. Overall, there is some improvement in perinatal survival and one-quarter incidence of rupture of the pregnant uterus.

  12. Nontraumatic spontaneous rupture of the kidney : etiology and CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Heo, Tae Haeng; Jeon, Hae Jeong; Shin, Hyun Joon [Konkuk Univ. College of Medicine, chungju (Korea, Republic of); Kim, Bo Hyun [Seongkyunkwan Univ. College of Medicine, Seoul (Korea, Republic of); Cho, Kyoung Sik [Ulsan Univ. College of Medicine, Ulsan (Korea, Republic of); Kim, Young Hwa [Soonchunhyang Univ. College of Medicine, Asan (Korea, Republic of); Kim, Seung Hyup [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of); Park, Churl Min [Korea Univ. College of Medicine, Seoul (Korea, Republic of)


    To evaluate the usefulness of CT scanning in determining the etiology of spontaneous rupture of the kidney We retrospectively analyzed the CT findings of spontaneous rupture of the kidney in eleven patients, Four were male and seven were female, and they were aged between 20 and 71 (mean, 46.6) years. Both pre- and post-contrast enhanced CT scanning was performed in all patients. Spontaneous renal rupture was induced in seven cases by neoplasms (three angiomyolipomas, three renal cell carcinomas, and one metastatic choriocarcinoma), in three cases by infection or inflammation (acute and chronic pyelonephritis, and renal abscess), and in one, by renal cyst. Common CT findings of rupture of the kidney were the accumulation of high density fluid in the perirenal and anterior pararenal space, and inhomogeneous irregular low density of renal parenchyma and the rupture site. Angiomyolipoma showed fat and an angiomatous component in the lesion, while acute and chronic pyelonephrities revealed thinning of the renal parenchyma and an irregular renal outline. Renal cell carcinoma showed a dense soft tissue mass in the parenchyma. Well-defined, round low-density lesions were noted in the case of renal cyst and renal abscess. CT is very useful in diagnosing and determining the etiology of non-traumatic spontaneous rupture of the kidney and plays an important role in the evaluation of emergency cases.

  13. The Surface Rupture of the 2010 El Mayor-Cucapah Earthquake and its Interaction with the 1892 Laguna Salada Rupture - Complex Fault Interaction in an Oblique Rift System (Invited) (United States)

    Rockwell, T. K.; Fletcher, J. M.; Teran, O.; Mueller, K. J.


    The 2010 El Mayor-Cucapah earthquake (Mw 7.2) demonstrates intimate mechanical interactions between two major fault systems that intersect within and along the western margin of the Sierra Cucapah in Baja California, Mexico. Rupture associated with 2010 earthquake produced ~4 m of dextral oblique slip and propagated through an imbricate stack of east-dipping faults. Toward the north, rupture consistently steps left to structurally deeper faults located farther west and in this manner passes through the core of the Sierra Cucapah to its western margin. The western margin of the Sierra Cucapah is defined by the Laguna Salada fault (LSF), which forms part of an active west-directed oblique detachment system recognized as the source of the large (M7+) February 22, 1892 earthquake. In the central Sierra Cucapah, the fault systems are separated by a narrow horst block, and here the 2010 event produced triggered slip on the LSF. These surface breaks follow the exact trace of the 1892 rupture, but their sense of slip (10-30 cm of pure normal displacement) differs radically from the 5 m of oblique dextral-normal slip produced by the 1892 event. Farther north, the narrow horst block is buried beneath strata of the northern Laguna Salada rift basin, and at this location, west-directed scarps of the LSF accommodate a significant component of dextral slip associated with the primary 2010 surface rupture. Thus, the two fault systems combine to accommodate oblique extension in the northern part of the range and likely have linking structures at fairly shallow depth. Newly identified paleo-scarps extend the known 1892 rupture length from 20 km to as much as 42 km, from the Canon Rojo fault to the Yuha Basin; consistent with a Mw 7.2 event and historical reports of MMI VII damage in San Diego. Both fault systems generate large earthquakes (>M7.2), with the west-directed LSF fault accommodating rapid subsidence in the adjacent basin during M7+ events at ~ 2Ka recurrence. Initial

  14. Computational modeling of unsteady surfactant-laden liquid plug propagation in neonatal airways (United States)

    Olgac, Ufuk; Muradoglu, Metin


    Surfactant-free and surfactant-laden liquid plug propagation in neonatal airways in various generations representing the upper and lower airways are investigated computationally using a finite-difference/front-tracking method. Emphasis is placed on the unsteady surfactant-laden plug propagation as a model for Surfactant Replacement Therapy (SRT) and airway reopening. The numerical method is designed to solve the evolution equations of the interfacial and bulk surfactant concentrations coupled with the incompressible Navier-Stokes equations. Available experimental data for surfactant Survanta are used to relate surface tension coefficient to surfactant concentration at the interface. It is found that, for the surfactant-free case, the trailing film thickness is in good agreement with Taylor's law for plugs with plug length greater than the airway width. Mechanical stresses that could be injurious to epithelial cells such as pressure and shear stress and their gradients are maximized on the front and rear menisci with increasing magnitudes in the lower generations. These mechanical stresses, especially pressure and pressure gradient, are diminished with the introduction of surfactants. Surfactant is absorbed onto the trailing film and thickens it, eventually leading to either plug rupture or, if totally consumed prior to rupture, to steadily propagating plug. In the upper airways, initially small plugs rupture rapidly and plugs with comparable initial plug length with the airway width persist and propagate steadily. For a more effective SRT treatment, we recommend utilization of plugs with initial plug length greater than the airway width. Increasing surfactant strength or increasing the initially instilled surfactant concentration is found to be ineffective.

  15. A database for propagation models (United States)

    Kantak, Anil V.; Suwitra, Krisjani; Le, Choung


    The NASA Propagation Program supports academic research that models various propagation phenomena in the space research frequency bands. NASA supports such research via school and institutions prominent in the field. The products of such efforts are particularly useful for researchers in the field of propagation phenomena and telecommunications systems engineers. The systems engineer usually needs a few propagation parameter values for a system design. Published literature on the subject, such as the Cunsultative Committee for International Radio (CCIR) publications, may help somewhat, but often times, the parameter values given in such publications use a particular set of conditions which may not quite include the requirements of the system design. The systems engineer must resort to programming the propagation phenomena model of interest and to obtain the parameter values to be used in the project. Furthermore, the researcher in the propagation field must then program the propagation models either to substantiate the model or to generate a new model. The researcher or the systems engineer must either be a skillful computer programmer or hire a programmer, which of course increases the cost of the effort. An increase in cost due to the inevitable programming effort may seem particularly inappropriate if the data generated by the experiment is to be used to substantiate the already well-established models, or a slight variation thereof. To help researchers and the systems engineers, it was recommended by the participants of NASA Propagation Experimenters (NAPEX) 15 held in London, Ontario, Canada on 28-29 June 1991, that propagation software should be constructed which will contain models and prediction methods of most propagation phenomenon. Moreover, the software should be flexible enough for the user to make slight changes to the models without expending a substantial effort in programming.

  16. Source Rupture Process of the 2008 Iwate-Miyagi Nairiku, Japan, Earthquake Revealed from Near Fault Strong Motion Records (United States)

    Suzuki, W.; Aoi, S.; Sekiguchi, H.


    We reveal the source rupture process of the 2008 Iwate-Miyagi Nairiku earthquake through the waveform inversion of the near fault strong motion records. At 8:43, June 14, 2008 (JST), a M7.2 shallow inland crustal earthquake struck Iwate and Miyagi Prefectures, northeast Japan. This earthquake, the 2008 Iwate-Miyagi Nairiku earthquake, is a reverse fault event, whose fault plane strikes to the southwest and dips to the northwest according to moment tensor solutions, aftershock distribution, and surface fault break. Strong motion networks, K-NET and KiK-net, operated by the National Research Institute for Earth Science and Disaster Prevention (NIED) obtained lots of the strong motion records at the near source region, which provide the information of the detailed source rupture process. We employ the multi-time-window linear waveform inversion method (Hartzell and Heaton, 1983). S-wave portion of the velocity waveforms (0.1-1 Hz) are used for the inversion. We use mainly borehole data at KiK- net stations. Green's functions are calculated using the discrete wavenumber method (Bouchon, 1981) and reflection/transmission coefficient matrix method (Kennett and Kerry, 1979) on the assumption of 1-D layered velocity structure. The rupture propagation effect within the subfault is included in the Green's function following Sekiguchi et al. (2002). Some stations are located on thick sediment. In order to take into account their effect on the observed waveforms, we construct the velocity structure model for each station referring to a 3-D subsurface structure model compiled for strong motion evaluation of whole Japan (Fujiwara et al., 2006). Validity of the assumed velocity structure is confirmed by simulating the aftershock records. The rupture starting point is set on the hypocenter relocated by Sekine et al. (2008) using double-difference method (Waldhauser and Ellsworth, 2000). Assumed fault plane covers a space of 40 km × 18 km. Its strike angle is 209° referring to F

  17. Are rupture zone limits of great subduction earthquakes controlled by upper plate structures? Evidence from multichannel seismic reflection data acquired across the northern Ecuador-southwest Colombia margin (United States)

    Collot, Jean-Yves; Marcaillou, Boris; Sage, FrançOise; Michaud, FrançOis; Agudelo, William; Charvis, Philippe; Graindorge, David; Gutscher, Marc-André; Spence, George


    Subduction of the Nazca plate beneath the Ecuador-Colombia margin has produced four megathrust earthquakes during the last century. The 500-km-long rupture zone of the 1906 (Mw = 8.8) event was partially reactivated by three thrust events, in 1942 (Mw = 7.8), 1958 (Mw = 7.7), and 1979 (Mw = 8.2), whose rupture zones abut one another. Multichannel seismic reflection and bathymetric data acquired during the SISTEUR cruise show evidence that the margin wedge is segmented by transverse crustal faults that potentially correlate with the limits of the earthquake coseismic slip zones. The Paleogene-Neogene Jama Quininde and Esmeraldas crustal faults define a ˜200-km-long margin crustal block that coincides with the 1942 earthquake rupture zone. Subduction of the buoyant Carnegie Ridge is inferred to partially lock the plate interface along central Ecuador. However, coseismic slip during the 1942 and 1906 earthquakes may have terminated against the subducted northern flank of the ridge. We report on a newly identified Manglares crustal fault that cuts transversally through the margin wedge and correlates with the limit between the 1958 and 1979 rupture zones. During the earthquake cycle the fault is associated with high-stress concentration on the plate interface. An outer basement high, which bounds the margin seaward of the 1958 rupture zone, may act as a deformable buttress to seaward propagation of coseismic slip along a megathrust splay fault. Coseismic uplift of the basement high is interpreted as the cause for the 1958 tsunami. We propose a model of weak transverse faults which reduce coupling between adjacent margin segments, together with a splay fault and an asperity along the plate interface as controlling the seismogenic rupture of the 1958 earthquake.

  18. Long-term functional outcome of bilateral spontaneous and simultaneous Achilles tendon ruptures.

    LENUS (Irish Health Repository)

    Ellanti, Prasad


    Bilateral simultaneous ruptures are rare comprising less than 1% of all Achilles tendon ruptures. Risk factors for bilateral ruptures include chronic diseases and medications such as corticosteroids and fluoroquinolones. There is little in the literature on the long-term functional outcome of bilateral Achilles tendon ruptures. This article present a series of 3 cases of simultaneous and spontaneous bilateral Achilles tendon ruptures with a minimum of 5-year follow up suggesting a good functional outcome.

  19. [Fluoroquinolone-induced Achilles tendon rupture]. (United States)

    Maurin, N


    A 72-year-old female dialysis patient with insulin-dependent diabetes mellitus who was under long-term medication with oral prednisolone due to chronic obstructive pulmonary disease was given levofloxacin for one week to treat an acute bronchitis (one 500 mg dose on the first day, 125 mg/day orally from second day onwards). One day after the end of levofloxacin treatment, the patient complained about a constant dragging pain above the right heel that receded under local application of diclofenac ointment and inactivity of the right foot. Twelve days after ending administration of levofloxacin, strong pains in the right calf were suddenly felt during normal walking, and active plantar flexion was lost. Palpation showed the right calf to be soft; a distinct gap was found in the middle third of the Achilles tendon. The Thompson test was positive, and the patient was unable to stand on her right toes. Ultrasonography showed a discontinuity of the right Achilles tendon. A spontaneous Achilles tendon rupture after taking fluoroquinolone was diagnosed. Conservative treatment was applied due to the reduced general condition. Initial treatment involved a below-knee plaster cast in equinus position; the cast was replaced on the fourth day by a pneumatic walker, which was also worn during mobilisation by physiotherapy. A typical feature of fluoroquinolone-induced tendinopathy (FIT) is a considerable latency period in some cases between the commencement of treatment with a fluoroquinolone and the onset of FIT symptoms. In addition to fluoroquinolone intake, there are three other predisposing risk factors for tendinopathy: age over 60 years, long-term treatment with systemic glucocorticoids, and chronic kidney disease. The patient showed a combination of all the aforementioned risk factors. In patients with these risk factors, especially among people with a combination of said risk factors - which is frequently the case with nephrologic and dialysis patients, especially

  20. A model to forecast magma chamber rupture (United States)

    Browning, John; Drymoni, Kyriaki; Gudmundsson, Agust


    An understanding of the amount of magma available to supply any given eruption is useful for determining the potential eruption magnitude and duration. Geodetic measurements and inversion techniques are often used to constrain volume changes within magma chambers, as well as constrain location and depth, but such models are incapable of calculating total magma storage. For example, during the 2012 unrest period at Santorini volcano, approximately 0.021 km3 of new magma entered a shallow chamber residing at around 4 km below the surface. This type of event is not unusual, and is in fact a necessary condition for the formation of a long-lived shallow chamber. The period of unrest ended without culminating in eruption, i.e the amount of magma which entered the chamber was insufficient to break the chamber and force magma further towards the surface. Using continuum-mechanics and fracture-mechanics principles, we present a model to calculate the amount of magma contained at shallow depth beneath active volcanoes. Here we discuss our model in the context of Santorini volcano, Greece. We demonstrate through structural analysis of dykes exposed within the Santorini caldera, previously published data on the volume of recent eruptions, and geodetic measurements of the 2011-2012 unrest period, that the measured 0.02% increase in volume of Santorini's shallow magma chamber was associated with magmatic excess pressure increase of around 1.1 MPa. This excess pressure was high enough to bring the chamber roof close to rupture and dyke injection. For volcanoes with known typical extrusion and intrusion (dyke) volumes, the new methodology presented here makes it possible to forecast the conditions for magma-chamber failure and dyke injection at any geodetically well-monitored volcano.

  1. Esophageal Rupture After Ghost Pepper Ingestion. (United States)

    Arens, Ann; Ben-Youssef, Leila; Hayashi, Sandra; Smollin, Craig


    The ghost pepper, or "bhut jolokia," is one of the hottest chili peppers in the world. Ghost peppers have a measured "heat" of > 1,000,000 Scoville heat units (SHU), more than twice the strength of a habanero pepper. To our knowledge, no significant adverse effects of ghost pepper ingestion have been reported. A 47-year-old man presented to the Emergency Department (ED) with severe abdominal and chest pain subsequent to violent retching and vomiting after eating ghost peppers as part of a contest. A subsequent chest x-ray study showed evidence of a left-sided pleural effusion and patchy infiltrates. A computed tomography scan of the abdomen and pelvis showed pneumomediastinum with air around the distal esophagus, suggestive of a spontaneous esophageal perforation and a left-sided pneumothorax. The patient was intubated and taken immediately to the operating room, where he was noted to have a 2.5-cm tear in the distal esophagus, with a mediastinal fluid collection including food debris, as well as a left-sided pneumothorax. The patient was extubated on hospital day 14, and was discharged home with a gastric tube in place on hospital day 23. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Spontaneous esophageal rupture, Boerhaave syndrome, is a rare condition encountered by emergency physicians, with a high mortality rate. This case serves as an important reminder of a potentially life- threatening surgical emergency initially interpreted as discomfort after a large spicy meal. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Seismic and Tsunami Waveform Simulation based on Dynamic Rupture Scenarios: Anticipated Nankai-Tonankai Earthquakes, Southwest Japan (United States)

    Saito, T.; Fukuyama, E.; Kim, S.


    Rupture scenarios of anticipated huge earthquakes based on earthquake physics and observational records should be useful for the hazard evaluation of future disastrous earthquakes. Hok et al. (2011, JGR) proposed possible dynamic rupture scenarios of anticipated Nankai-Tonankai huge earthquakes, southwest Japan using estimated slip deficit distribution and an appropriate fault friction law. These scenarios are quite useful to study the details of the wave propagation as well as potential earthquake and tsunami hazard (e.g. Kim et al. 2016, EPS). The objective in this study is to synthesize seismic and tsunami waveforms of the anticipated huge earthquakes, which could be useful for the future hazard assessment. We propose a method of synthesizing the waveforms, in particular, in the region of offshore focal area where seismic waves, ocean acoustic waves, and tsunamis simultaneously exist, which makes the wavefield very complicated. We calculated the seismic and tsunami waveforms caused by a dynamic rupture of huge earthquakes (Mw 8.5) southwestern Japan. There are two kinds of tsunami observations: ocean bottom pressure gauges detect tsunami as pressure change at the sea bottom and GPS tsunami gauges measure tsunami as vertical displacement at the sea surface. Our simulation results indicated that both tsunami records are significantly contaminated by seismic waves in a few minutes after the earthquake occurrence. The tsunami and seismic waves have different excitation mechanisms: seismic wave excitation strongly depends on the time scale of the rupture (moment rate), while tsunami excitation is determined by the static parameters (fault geometry and seismic moment). Therefore, for a reliable tsunami prediction, it is important to analyze observed tsunami records excluding the seismic waves that behave like tsunami near the source area.

  3. Dike Propagation Near Drifts

    Energy Technology Data Exchange (ETDEWEB)



    The purpose of this Analysis and Model Report (AMR) supporting the Site Recommendation/License Application (SR/LA) for the Yucca Mountain Project is the development of elementary analyses of the interactions of a hypothetical dike with a repository drift (i.e., tunnel) and with the drift contents at the potential Yucca Mountain repository. This effort is intended to support the analysis of disruptive events for Total System Performance Assessment (TSPA). This AMR supports the Process Model Report (PMR) on disruptive events (CRWMS M&O 2000a). This purpose is documented in the development plan (DP) ''Coordinate Modeling of Dike Propagation Near Drifts Consequences for TSPA-SR/LA'' (CRWMS M&O 2000b). Evaluation of that Development Plan and the work to be conducted to prepare Interim Change Notice (ICN) 1 of this report, which now includes the design option of ''Open'' drifts, indicated that no revision to that DP was needed. These analyses are intended to provide reasonable bounds for a number of expected effects: (1) Temperature changes to the waste package from exposure to magma; (2) The gas flow available to degrade waste containers during the intrusion; (3) Movement of the waste package as it is displaced by the gas, pyroclasts and magma from the intruding dike (the number of packages damaged); (4) Movement of the backfill (Backfill is treated here as a design option); (5) The nature of the mechanics of the dike/drift interaction. These analyses serve two objectives: to provide preliminary analyses needed to support evaluation of the consequences of an intrusive event and to provide a basis for addressing some of the concerns of the Nuclear Regulatory Commission (NRC) expressed in the Igneous Activity Issue Resolution Status Report.

  4. Laser beam propagation generation and propagation of customized light

    CERN Document Server

    Forbes, Andrew


    ""The text is easy to read and is accompanied by beautiful illustrations. It is an excellent book for anyone working in laser beam propagation and an asset for any library.""-Optics & Photonics News, July 2014

  5. Vortex dynamics in ruptured and unruptured intracranial aneurysms (United States)

    Trylesinski, Gabriel

    Intracranial aneurysms (IAs) are a potentially devastating pathological dilation of brain arteries that affect 1.5-5 % of the population. Causing around 500 000 deaths per year worldwide, their detection and treatment to prevent rupture is critical. Multiple recent studies have tried to find a hemodynamics predictor of aneurysm rupture, but concluded with distinct opposite trends using Wall Shear Stress (WSS) based parameters in different clinical datasets. Nevertheless, several research groups tend to converge for now on the fact that the flow patterns and flow dynamics of the ruptured aneurysms are complex and unstable. Following this idea, we investigated the vortex properties of both unruptured and ruptured cerebral aneurysms. A brief comparison of two Eulerian vortex visualization methods (Q-criterion and lambda 2 method) showed that these approaches gave similar results in our complex aneurysm geometries. We were then able to apply either one of them to a large dataset of 74 patient specific cases of intracranial aneurysms. Those real cases were obtained by 3D angiography, numerical reconstruction of the geometry, and then pulsatile CFD simulation before post-processing with the mentioned vortex visualization tools. First we tested the two Eulerian methods on a few cases to verify their implementation we made as well as compare them with each other. After that, the Q-criterion was selected as method of choice for its more obvious physical meaning (it shows the balance between two characteristics of the flow, its swirling and deformation). Using iso-surfaces of Q, we started by categorizing the patient-specific aneurysms based on the gross topology of the aneurysmal vortices. This approach being unfruitful, we found a new vortex-based characteristic property of ruptured aneurysms to stratify the rupture risk of IAs that we called the Wall-Kissing Vortices, or WKV. We observed that most ruptured aneurysms had a large amount of WKV, which appears to agree with

  6. Radial propagators and Wilson loops

    CERN Document Server

    Leupold, S; Leupold, Stefan; Weigert, Heribert


    We present a relation which connects the propagator in the radial (Fock-Schwinger) gauge with a gauge invariant Wilson loop. It is closely related to the well-known field strength formula and can be used to calculate the radial gauge propagator. The result is shown to diverge in four-dimensional space even for free fields, its singular nature is however naturally explained using the renormalization properties of Wilson loops with cusps and self-intersections. Using this observation we provide a consistent regularization scheme to facilitate loop calculations. Finally we compare our results with previous approaches to derive a propagator in Fock-Schwinger gauge.

  7. Particle propagation in cosmological backgrounds

    CERN Document Server

    Arteaga, Daniel


    We study the quantum propagation of particles in cosmological backgrounds, by considering a doublet of massive scalar fields propagating in an expanding universe, possibly filled with radiation. We focus on the dissipative effects related to the expansion rate. At first order, we recover the expected result that the decay rate is determined by the local temperature. Beyond linear order, the decay rate has an additional contribution governed by the expansion parameter. This latter contribution is present even for stable particles in the vacuum. Finally, we analyze the long time behaviour of the propagator and briefly discuss applications to the trans-Planckian question.

  8. Light Propagation For Accelerated Observers

    CERN Document Server

    Adewole, A I A


    We show that for an observer in translational, rotational or gravitational motion, a linearly polarized plane wave has two modes of propagation in a stationary, homogeneous and isotropic medium according to Hertz's version of Maxwell's theory. The first mode is characterized by polarization at right angles to the direction of propagation and has a phase velocity that is controlled by the material constants of the medium. The second mode is characterized by polarization along the propagation direction and has a phase velocity that is controlled by the motion of the observer. We outline some applications of the second mode in emerging technologies.


    Directory of Open Access Journals (Sweden)

    Andrei G. Marchuk


    Full Text Available This is a study of tsunami wave propagation along the waveguide on a bottom ridge with flat sloping sides, using the wave rays method. During propagation along such waveguide the single tsunami wave transforms into a wave train. The expression for the guiding velocities of the fastest and slowest signals is defined. The tsunami wave behavior above the ocean bottom ridges, which have various model profiles, is investigated numerically with the help of finite difference method. Results of numerical experiments show that the highest waves are detected above a ridge with flat sloping sides. Examples of tsunami propagation along bottom ridges of the Pacific Ocean are presented.

  10. Energy budget and propagation of faults via shearing and opening using work optimization (United States)

    Madden, Elizabeth H.; Cooke, Michele L.; McBeck, Jessica


    We present numerical models of faults propagating by work optimization in a homogeneous medium. These simulations allow quantification and comparison of the energy budgets of fault growth by shear versus tensile failure. The energy consumed by growth of a fault, Wgrow, propagating by in-line shearing is 76% of the total energy associated with that growth, while 24% is spent on frictional work during propagation. Wgrow for a fault propagating into intact rock by tensile failure, at an angle to the parent fault, consumes 60% of the work budget, while only 6% is consumed by frictional work associated with propagation. Following the conservation of energy, this leaves 34% of the energy budget available for other activities and suggests that out-of-plane propagation of faults in Earth's crust may release energy for other processes, such as permanent damage zone formation or rupture acceleration. Comparison of these estimates of Wgrow with estimates of the critical energy release rate and earthquake fracture energy at several scales underscores their theoretical similarities and their dependence on stress drop.

  11. Thrust fault segmentation and downward fault propagation in accretionary wedges: New Insights from 3D seismic reflection data (United States)

    Orme, Haydn; Bell, Rebecca; Jackson, Christopher


    The shallow parts of subduction megathrust faults are typically thought to be aseismic and incapable of propagating seismic rupture. The 2011 Tohoku-Oki earthquake, however, ruptured all the way to the trench, proving that in some locations rupture can propagate through the accretionary wedge. An improved understanding of the structural character and physical properties of accretionary wedges is therefore crucial to begin to assess why such anomalously shallow seismic rupture occurs. Despite its importance, we know surprisingly little regarding the 3D geometry and kinematics of thrust network development in accretionary prisms, largely due to a lack of 3D seismic reflection data providing high-resolution, 3D images of entire networks. Thus our current understanding is largely underpinned by observations from analogue and numerical modelling, with limited observational data from natural examples. In this contribution we use PSDM, 3D seismic reflection data from the Nankai margin (3D Muroto dataset, available from the UTIG Academic Seismic Portal, Marine Geoscience Data System) to examine how imbricate thrust fault networks evolve during accretionary wedge growth. We unravel the evolution of faults within the protothrust and imbricate thrust zones by interpreting multiple horizons across faults and measuring fault displacement and fold amplitude along-strike; by doing this, we are able to investigate the three dimensional accrual of strain. We document a number of local displacement minima along-strike of faults, suggesting that, the protothrust and imbricate thrusts developed from the linkage of smaller, previously isolated fault segments. Although we often assume imbricate faults are likely to have propagated upwards from the décollement we show strong evidence for fault nucleation at shallow depths and downward propagation to intersect the décollement. The complex fault interactions documented here have implications for hydraulic compartmentalisation and pore

  12. Composite Overwrap Pressure Vessels: Mechanics and Stress Rupture Lifing Philosophy (United States)

    Thesken, John C.; Murthy, Pappu L. N.; Phoenix, Leigh


    The NASA Engineering and Safety Center (NESC) has been conducting an independent technical assessment to address safety concerns related to the known stress rupture failure mode of filament wound pressure vessels in use on Shuttle and the International Space Station. The Shuttle's Kevlar-49 fiber overwrapped tanks are of particular concern due to their long usage and the poorly understood stress rupture process in Kevlar-49 filaments. Existing long term data show that the rupture process is a function of stress, temperature and time. However due to the presence of load sharing liners and the complex manufacturing procedures, the state of actual fiber stress in flight hardware and test articles is not clearly known. Indeed non-conservative life predictions have been made where stress rupture data and lifing procedures have ignored the contribution of the liner in favor of applied pressure as the controlling load parameter. With the aid of analytical and finite element results, this paper examines the fundamental mechanical response of composite overwrapped pressure vessels including the influence of elastic-plastic liners and degraded/creeping overwrap properties. Graphical methods are presented describing the non-linear relationship of applied pressure to Kevlar-49 fiber stress/strain during manufacturing, operations and burst loadings. These are applied to experimental measurements made on a variety of vessel systems to demonstrate the correct calibration of fiber stress as a function of pressure. Applying this analysis to the actual qualification burst data for Shuttle flight hardware revealed that the nominal fiber stress at burst was in some cases 23% lower than what had previously been used to predict stress rupture life. These results motivate a detailed discussion of the appropriate stress rupture lifing philosophy for COPVs including the correct transference of stress rupture life data between dissimilar vessels and test articles.

  13. Composite Overwrap Pressure Vessels: Mechanics and Stress Rupture Lifting Philosophy (United States)

    Thesken, John C.; Murthy, Pappu L. N.; Phoenix, S. L.


    The NASA Engineering and Safety Center (NESC) has been conducting an independent technical assessment to address safety concerns related to the known stress rupture failure mode of filament wound pressure vessels in use on Shuttle and the International Space Station. The Shuttle s Kevlar-49 (DuPont) fiber overwrapped tanks are of particular concern due to their long usage and the poorly understood stress rupture process in Kevlar-49 filaments. Existing long term data show that the rupture process is a function of stress, temperature and time. However due to the presence of load sharing liners and the complex manufacturing procedures, the state of actual fiber stress in flight hardware and test articles is not clearly known. Indeed nonconservative life predictions have been made where stress rupture data and lifing procedures have ignored the contribution of the liner in favor of applied pressure as the controlling load parameter. With the aid of analytical and finite element results, this paper examines the fundamental mechanical response of composite overwrapped pressure vessels including the influence of elastic plastic liners and degraded/creeping overwrap properties. Graphical methods are presented describing the non-linear relationship of applied pressure to Kevlar-49 fiber stress/strain during manufacturing, operations and burst loadings. These are applied to experimental measurements made on a variety of vessel systems to demonstrate the correct calibration of fiber stress as a function of pressure. Applying this analysis to the actual qualification burst data for Shuttle flight hardware revealed that the nominal fiber stress at burst was in some cases 23 percent lower than what had previously been used to predict stress rupture life. These results motivate a detailed discussion of the appropriate stress rupture lifing philosophy for COPVs including the correct transference of stress rupture life data between dissimilar vessels and test articles.

  14. How geometry and structure control the seismic radiation : spectral element simulation of the dynamic rupture of the Mw 9.0 Tohoku earthquake (United States)

    Festa, G.; Vilotte, J.; Scala, A.


    The M 9.0, 2011 Tohoku earthquake, along the North American-Pacific plate boundary, East of the Honshu Island, yielded a complex broadband rupture extending southwards over 600 km along strike and triggering a large tsunami that ravaged the East coast of North Japan. Strong motion and high-rate continuous GPS data, recorded all along the Japanese archipelago by the national seismic networks K-Net and Kik-net and geodetic network Geonet, together with teleseismic data, indicated a complex frequency dependent rupture. Low frequency signals (fmeters), extending along-dip over about 100 km, between the hypocenter and the trench, and 150 to 200 km along strike. This slip asperity was likely the cause of the localized tsunami source and of the large amplitude tsunami waves. High-frequency signals (f>0.5 Hz) were instead generated close to the coast in the deeper part of the subduction zone, by at least four smaller size asperities, with possible repeated slip, and were mostly the cause for the ground shaking felt in the Eastern part of Japan. The deep origin of the high-frequency radiation was also confirmed by teleseismic high frequency back projection analysis. Intermediate frequency analysis showed a transition between the shallow and deeper part of the fault, with the rupture almost confined in a small stripe containing the hypocenter before propagating southward along the strike, indicating a predominant in-plane rupture mechanism in the initial stage of the rupture itself. We numerically investigate the role of the geometry of the subduction interface and of the structural properties of the subduction zone on the broadband dynamic rupture and radiation of the Tohoku earthquake. Based upon the almost in-plane behavior of the rupture in its initial stage, 2D non-smooth spectral element dynamic simulations of the earthquake rupture propagation are performed including the non planar and kink geometry of the subduction interface, together with bi-material interfaces

  15. Wave propagation in electromagnetic media

    CERN Document Server

    Davis, Julian L


    This is the second work of a set of two volumes on the phenomena of wave propagation in nonreacting and reacting media. The first, entitled Wave Propagation in Solids and Fluids (published by Springer-Verlag in 1988), deals with wave phenomena in nonreacting media (solids and fluids). This book is concerned with wave propagation in reacting media-specifically, in electro­ magnetic materials. Since these volumes were designed to be relatively self­ contained, we have taken the liberty of adapting some of the pertinent material, especially in the theory of hyperbolic partial differential equations (concerned with electromagnetic wave propagation), variational methods, and Hamilton-Jacobi theory, to the phenomena of electromagnetic waves. The purpose of this volume is similar to that of the first, except that here we are dealing with electromagnetic waves. We attempt to present a clear and systematic account of the mathematical methods of wave phenomena in electromagnetic materials that will be readily accessi...

  16. Reconstruction of nonlinear wave propagation (United States)

    Fleischer, Jason W; Barsi, Christopher; Wan, Wenjie


    Disclosed are systems and methods for characterizing a nonlinear propagation environment by numerically propagating a measured output waveform resulting from a known input waveform. The numerical propagation reconstructs the input waveform, and in the process, the nonlinear environment is characterized. In certain embodiments, knowledge of the characterized nonlinear environment facilitates determination of an unknown input based on a measured output. Similarly, knowledge of the characterized nonlinear environment also facilitates formation of a desired output based on a configurable input. In both situations, the input thus characterized and the output thus obtained include features that would normally be lost in linear propagations. Such features can include evanescent waves and peripheral waves, such that an image thus obtained are inherently wide-angle, farfield form of microscopy.

  17. Propagation engineering in wireless communications

    CERN Document Server

    Ghasemi, Abdollah; Ghasemi, Farshid


    This book covers the basic principles for understanding radio wave propagation for common frequency bands used in radio-communications. This includes achievements and developments in propagation models for wireless communication. This book is intended to bridge the gap between the theoretical calculations and approaches to the applied procedures needed for radio links design in a proper manner. The authors emphasize propagation engineering by giving fundamental information and explain the use of basic principles together with technical achievements. This new edition includes additional information on radio wave propagation in guided media and technical issues for fiber optics cable networks with several examples and problems. This book also includes a solution manual - with 90 solved examples distributed throughout the chapters - and 158 problems including practical values and assumptions.

  18. Ultra High Energy Nuclei Propagation

    CERN Document Server

    Aloisio, Roberto


    We discuss the problem of ultra high energy nuclei propagation in astrophysical backgrounds. We present a new analytical computation scheme based on the hypothesis of continuos energy losses in a kinetic formulation of the particles propagation. This scheme enables the computation of the fluxes of ultra high energy nuclei as well as the fluxes of secondaries (nuclei and nucleons) produced by the process of photo-disintegration suffered by nuclei.

  19. Rupture de la pédagogie et pédagogie de la rupture

    Directory of Open Access Journals (Sweden)

    Frank Jablonka


    Full Text Available 1. Discours et contre-discours de la rupture1.1. La présente contribution a pour but de proposer quelques considérations intempestives par rapport aux conceptions pédagogiques dominantes et à la politique éducative actuellement mise en œuvre en France. Si les problèmes ne sont, certes, pas nouveaux, ils ont été exacerbés depuis 2007, conjointement aux conceptions sous-jacentes et à leur mise en œuvre autoritaire et "décomplexée" par le nouveau gouvernement. Ce symptôme de décadence apparaît d...

  20. Composite Overwrapped Pressure Vessels (COPV) Stress Rupture Test (United States)

    Russell, Richard; Flynn, Howard; Forth, Scott; Greene, Nathanael; Kezian, Michael; Varanauski, Don; Yoder, Tommy; Woodworth, Warren


    One of the major concerns for the aging Space Shuttle fleet is the stress rupture life of composite overwrapped pressure vessels (COPVs). Stress rupture life of a COPV has been defined as the minimum time during which the composite maintains structural integrity considering the combined effects of stress levels and time. To assist in the evaluation of the aging COPVs in the Orbiter fleet an analytical reliability model was developed. The actual data used to construct this model was from testing of COPVs constructed of similar, but not exactly same materials and pressure cycles as used on Orbiter vessels. Since no actual Orbiter COPV stress rupture data exists the Space Shuttle Program decided to run a stress rupture test to compare to model predictions. Due to availability of spares, the testing was unfortunately limited to one 40" vessel. The stress rupture test was performed at maximum operating pressure at an elevated temperature to accelerate aging. The test was performed in two phases. The first phase, 130 F, a moderately accelerated test designed to achieve the midpoint of the model predicted point reliability. The more aggressive second phase, performed at 160 F was designed to determine if the test article will exceed the 95% confidence interval of the model. This paper will discuss the results of this test, it's implications and possible follow-on testing.

  1. Surgical treatment of the neglected achilles tendon rupture with Hyalonect. (United States)

    Esenyel, Cem Zeki; Tekin, Cagri; Cakar, Murat; Bayraktar, Kursat; Saygili, Selcuk; Esenyel, Meltem; Tekin, Zeynep N


    The purpose of this study was to report the management and outcomes of ten patients with chronic Achilles tendon rupture treated with a turndown gastrocnemius-soleus fascial flap wrapped with a surgical mesh (Hyalonect). Ten men with neglected Achilles tendon rupture were treated with a centrally based turndown gastrocnemius fascial flap wrapped with Hyalonect. Hyalonect is a knitted mesh composed of HYAFF, a benzyl ester of hyaluronic acid. The Achilles tendon ruptures were diagnosed more than 1 month after injury. The mean patient age was 41 years. All of the patients had weakness of active plantarflexion. The mean preoperative American Orthopaedic Foot and Ankle Society score was 64.8. The functional outcome was excellent. The mean American Orthopaedic Foot and Ankle Society score was 97.8 at the latest follow-up. There were significant differences between the preoperative and postoperative scores. Ankle range of motion was similar in both ankles. Neither rerupture nor major complication, particularly of wound healing, was observed. For patients with chronic Achilles tendon rupture with a rupture gap of at least 5 cm, surgical repair using a single turndown fascial flap covered with Hyalonect achieved excellent outcomes.

  2. Ruptures of the anterior cruciate ligament in soccer. (United States)

    Rochcongar, P; Laboute, E; Jan, J; Carling, C


    Ruptures of the anterior cruciate ligament (ACL) are serious, common and costly injuries. The present 12-year investigation was undertaken to examine the frequency of ACL ruptures and identify the game events that may have contributed to the cause of these injuries in male soccer players across a French district. A retrospective questionnaire was used to record the players' age at the time of injury, laterality, standard of play, playing position and injured side. The characteristics of the injury situations were described in detail to investigate the game events involved in each case. A total of 934 ruptures was reported. Significantly more ruptures were sustained in a non-contact versus a contact situation (pgame events reported in the injury situations were shown to be related to player's age, standard and position. While these results have confirmed observations from previous investigations on ACL ruptures in soccer, the analysis of a considerably larger number of injury cases has brought new findings to the literature as well as recommendations for future research.

  3. Spontaneous splenic rupture in Waldenstrom's macroglobulinemia: a case report

    Directory of Open Access Journals (Sweden)

    Charakidis Michail


    Full Text Available Abstract Introduction We report the case of a patient with Waldenstrom's macroglobulinemia complicated by spontaneous splenic rupture. Case presentation A 49-year-old Caucasian woman was referred to our emergency department by her general practitioner following a three-week history of malaise, night sweats, six kilograms of weight loss, intermittent nausea and vomiting, progressive upper abdominal pain and easy bruising. On the fourth day following her admission, she had a rapid clinical deterioration, with subsequent radiological investigations revealing a splenic rupture. Her morphology, biochemistry, flow cytometry and histology were strongly suggestive of Waldenstrom's macroglobulinemia. Conclusions Spontaneous splenic rupture is not an expected complication of low-grade lymphoplasmacytic lymphomas, such as Waldenstrom's macroglobulinemia. To the best of our knowledge, this is the only reported case of early spontaneous splenic rupture due to Waldenstrom's macroglobulinemia. Our case highlights that despite the typical disease course of low-grade hematological malignancies, signs and symptoms of imminent splenic rupture should be considered when formulating a clinical assessment.

  4. Spontaneous unscarred fundal rupture after normal vaginal delivery

    Directory of Open Access Journals (Sweden)

    Shreya Thapa


    Full Text Available Uterine rupture is one of the most dangerous obstetric situation carrying an increased risk of maternal and perinatal morbidity and mortality, associated with poorly managed labour. The incidence of spontaneous rupture of unscarred uterus is around 1 in 8000 to 1 in 15000 deliveries. We report this unusual case of spontaneous unscarred fundal rupture after normal vaginal delivery. This case under reference developed shock soon after delivery and was explored due to suspected intraperitoneal hemorrhage. This case is being reported to emphasis the need for proper post-delivery monitoring not only to diagnose post-partum hemorrhage but also to suspect uterine rupture as a cause of unexplained shock developing after delivery inspite of all resuscitative measures. Although unexpected in a woman with an unscarred uterus, rupture should be considered as a possible cause of unusual pain or hypotension in the mother. The most effective way to reduce the number of morbidity and mortality would be to prevent unwanted pregnancies by informed and effective use of contraception. [Int J Reprod Contracept Obstet Gynecol 2014; 3(3.000: 780-782

  5. Direct visualization of microalgae rupture by ultrasound-driven bubbles (United States)

    Pommella, Angelo; Harun, Irina; Pouliopoulos, Antonis; Choi, James J.; Hellgardt, Klaus; Garbin, Valeria


    Cell rupture induced by ultrasound is central to applications in biotechnology. For instance, cell disruption is required in the production of biofuels from microalgae (unicellular species of algae). Ultrasound-induced cavitation, bubble collapse and jetting are exploited to induce sufficiently large viscous stresses to cause rupture of the cell membranes. It has recently been shown that seeding the flow with bubbles that act as cavitation nuclei significantly reduces the energy cost for cell processing. However, a fundamental understanding of the conditions for rupture of microalgae in the complex flow fields generated by ultrasound-driven bubbles is currently lacking. We perform high-speed video microscopy to visualize the miscroscale details of the interaction of Chlamydomonas reinhardtii , microalgae of about 10 μm in size, with ultrasound-driven microbubbles of 2-200 μm in diameter. We investigate the efficiency of cell rupture depending on ultrasound frequency and pressure amplitude (from 10 kPa up to 1 MPa), and the resulting bubble dynamics regimes. In particular we compare the efficiency of membrane rupture in the acoustic microstreaming flow induced by linear oscillations, with the case of violent bubble collapse and jetting. V.G. acknowledges partial support from the European Commission (FP7-PEOPLE-2013-CIG), Grant No. 618333.

  6. Propagation in Diagonal Anisotropic Chirowaveguides

    Directory of Open Access Journals (Sweden)

    S. Aib


    Full Text Available A theoretical study of electromagnetic wave propagation in parallel plate chirowaveguide is presented. The waveguide is filled with a chiral material having diagonal anisotropic constitutive parameters. The propagation characterization in this medium is based on algebraic formulation of Maxwell’s equations combined with the constitutive relations. Three propagation regions are identified: the fast-fast-wave region, the fast-slow-wave region, and the slow-slow-wave region. This paper focuses completely on the propagation in the first region, where the dispersion modal equations are obtained and solved. The cut-off frequencies calculation leads to three cases of the plane wave propagation in anisotropic chiral medium. The particularity of these results is the possibility of controlling the appropriate cut-off frequencies by choosing the adequate physical parameters values. The specificity of this study lies in the bifurcation modes confirmation and the possible contribution to the design of optical devices such as high-pass filters, as well as positive and negative propagation constants. This negative constant is an important feature of metamaterials which shows the phenomena of backward waves. Original results of the biaxial anisotropic chiral metamaterial are obtained and discussed.

  7. The physical theory and propagation model of THz atmospheric propagation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, R; Yao, J Q; Xu, D G; Wang, J L; Wang, P, E-mail: [College of Precision Instrument and Opto-electronics Engineering, Institute of Laser and Opto-electronics, Tianjin University, Tianjin 300072 (China)


    Terahertz (THz) radiation is extensively applied in diverse fields, such as space communication, Earth environment observation, atmosphere science, remote sensing and so on. And the research on propagation features of THz wave in the atmosphere becomes more and more important. This paper firstly illuminates the advantages and outlook of THz in space technology. Then it introduces the theoretical framework of THz atmospheric propagation, including some fundamental physical concepts and processes. The attenuation effect (especially the absorption of water vapor), the scattering of aerosol particles and the effect of turbulent flow mainly influence THz atmosphere propagation. Fundamental physical laws are illuminated as well, such as Lamber-beer law, Mie scattering theory and radiative transfer equation. The last part comprises the demonstration and comparison of THz atmosphere propagation models like Moliere(V5), SARTre and AMATERASU. The essential problems are the deep analysis of physical mechanism of this process, the construction of atmospheric propagation model and databases of every kind of material in the atmosphere, and the standardization of measurement procedures.

  8. The physical theory and propagation model of THz atmospheric propagation (United States)

    Wang, R.; Yao, J. Q.; Xu, D. G.; Wang, J. L.; Wang, P.


    Terahertz (THz) radiation is extensively applied in diverse fields, such as space communication, Earth environment observation, atmosphere science, remote sensing and so on. And the research on propagation features of THz wave in the atmosphere becomes more and more important. This paper firstly illuminates the advantages and outlook of THz in space technology. Then it introduces the theoretical framework of THz atmospheric propagation, including some fundamental physical concepts and processes. The attenuation effect (especially the absorption of water vapor), the scattering of aerosol particles and the effect of turbulent flow mainly influence THz atmosphere propagation. Fundamental physical laws are illuminated as well, such as Lamber-beer law, Mie scattering theory and radiative transfer equation. The last part comprises the demonstration and comparison of THz atmosphere propagation models like Moliere(V5), SARTre and AMATERASU. The essential problems are the deep analysis of physical mechanism of this process, the construction of atmospheric propagation model and databases of every kind of material in the atmosphere, and the standardization of measurement procedures.

  9. Fracture in Westerly granite under AE feedback and constant strain rate loading: Nucleation, quasi-static propagation, and the transition to unstable fracture propagation (United States)

    Thompson, B.D.; Young, R.P.; Lockner, D.A.


    New observations of fracture nucleation are presented from three triaxial compression experiments on intact samples of Westerly granite, using Acoustic Emission (AE) monitoring. By conducting the tests under different loading conditions, the fracture process is demonstrated for quasi-static fracture (under AE Feedback load), a slowly developing unstable fracture (loaded at a 'slow' constant strain rate of 2.5 ?? 10-6/s) and an unstable fracture that develops near instantaneously (loaded at a 'fast' constant strain rate of 5 ?? 10-5/s). By recording a continuous ultrasonic waveform during the critical period of fracture, the entire AE catalogue can be captured and the exact time of fracture defined. Under constant strain loading, three stages are observed: (1) An initial nucleation or stable growth phase at a rate of ??? 1.3 mm/s, (2) a sudden increase to a constant or slowly accelerating propagation speed of ??? 18 mm/s, and (3) unstable, accelerating propagation. In the ??? 100 ms before rupture, the high level of AE activity (as seen on the continuous record) prevented the location of discrete AE events. A lower bound estimate of the average propagation velocity (using the time-to-rupture and the existing fracture length) suggests values of a few m/s. However from a low gain acoustic record, we infer that in the final few ms, the fracture propagation speed increased to 175 m/s. These results demonstrate similarities between fracture nucleation in intact rock and the nucleation of dynamic instabilities in stick slip experiments. It is suggested that the ability to constrain the size of an evolving fracture provides a crucial tool in further understanding the controls on fracture nucleation. ?? Birkha??user Verlag, Basel, 2006.

  10. [Neurologic complications of subarachnoid hemorrhage due to intracranial aneurysm rupture]. (United States)

    Rama-Maceiras, P; Fàbregas Julià, N; Ingelmo Ingelmo, I; Hernández-Palazón, J


    The high rates of morbidity and mortality after subarachnoid hemorrhage due to spontaneous rupture of an intracranial aneurysm are mainly the result of neurologic complications. Sixty years after cerebral vasospasm was first described, this problem remains unsolved in spite of its highly adverse effect on prognosis after aneurysmatic rupture. Treatment is somewhat empirical, given that uncertainties remain in our understanding of the pathophysiology of this vascular complication, which involves structural and biochemical changes in the endothelium and smooth muscle of vessels. Vasospasm that is refractory to treatment leads to cerebral infarction. Prophylaxis, early diagnosis, and adequate treatment of neurologic complications are key elements in the management of vasospasm if neurologic damage, lengthy hospital stays, and increased use of health care resources are to be avoided. New approaches to early treatment of cerebral lesions and cortical ischemia in cases of subarachnoid hemorrhage due to aneurysm rupture should lead to more effective, specific management.

  11. "Ruptured" malignant phyllodes tumor of the breast: a case report

    Directory of Open Access Journals (Sweden)

    Ditsatham C


    Full Text Available Chagkrit Ditsatham, Areewan Somwangprasert, Kirati Watcharachan, Phanchaporn WongmaneerungDivision of Head, Neck and Breast, Department of Surgery, Chiang Mai University, Chiang Mai, ThailandAbstract: Phyllodes tumor or cystosarcoma phyllodes is a rare disease and is usually seen in middle-aged patients. Ruptured phyllodes tumor is a very rare condition. Our study reports patient presentation, diagnosis method, and treatment of an unusual case. A 58-year-old premenopausal female was diagnosed with a phyllodes tumor and presented with a rapidly growing mass for 2 months that ruptured 1 month later. She underwent simple mastectomy at the left side of her breast and received adjuvant radiotherapy. No recurrence was found 4 months after operation.Keywords: ruptured, malignant, phyllodes tumor, breast 

  12. Spontaneous Rupture of Pancreatic Pseudocyst: Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Ricardo Rocha


    Full Text Available Introduction. Pancreatic pseudocysts are a common complication of acute pancreatitis. Pancreatic pseudocyst’s natural history ranges between its spontaneous regression and the settlement of serious complications if untreated, such as splenic complications, hemorrhage, infection, biliary complications, portal hypertension, and rupture. The rupture of a pancreatic pseudocyst to the peritoneal cavity is a dangerous complication leading to severe peritonitis and septic conditions. It requires emergent surgical exploration that is often of great technical difficulty and with important morbidity and mortality. Case Study. We present two cases of spontaneous rupture of pancreatic pseudocysts, managed differently according to the local and systemic conditions. Conclusion. The best surgical choice is the internal drainage of the cyst to the GI tract; however, in some conditions, the external drainage is the only choice available.

  13. Standards for Documenting Finite‐Fault Earthquake Rupture Models

    KAUST Repository

    Mai, Paul Martin


    In this article, we propose standards for documenting and disseminating finite‐fault earthquake rupture models, and related data and metadata. A comprehensive documentation of the rupture models, a detailed description of the data processing steps, and facilitating the access to the actual data that went into the earthquake source inversion are required to promote follow‐up research and to ensure interoperability, transparency, and reproducibility of the published slip‐inversion solutions. We suggest a formatting scheme that describes the kinematic rupture process in an unambiguous way to support subsequent research. We also provide guidelines on how to document the data, metadata, and data processing. The proposed standards and formats represent a first step to establishing best practices for comprehensively documenting input and output of finite‐fault earthquake source studies.

  14. Nonoperative dynamic treatment of acute achilles tendon rupture

    DEFF Research Database (Denmark)

    Barfod, Kristoffer Weisskirchner; Bencke, Jesper; Bloch Lauridsen, Hanne


    BACKGROUND: Dynamic rehabilitation has been suggested to be an important part of nonoperative treatment of acute Achilles tendon rupture that results in functional outcome and rerupture rates comparable with those of operative treatment. However, the optimal role of weight-bearing during early...... rehabilitation remains unclear. The purpose of this study was to compare immediate weight-bearing with non-weight-bearing in a nonoperative dynamic treatment protocol for Achilles tendon rupture. METHODS: The study was conducted as a blinded, randomized, controlled, parallel superiority trial. Patients eighteen...... to sixty years of age were eligible for inclusion. Both groups were treated nonoperatively with controlled early motion. The intervention group was allowed full weight-bearing from day one, and the control group was non-weight-bearing for six weeks. The primary outcome was the Achilles tendon Total Rupture...

  15. [Neglected ipsilateral simultaneous ruptures of patellar and quadriceps tendon]. (United States)

    Karahasanoğlu, İlker; Yoloğlu, Osman; Kerimoğlu, Servet; Turhan, Ahmet Uğur


    Neglected patellar and quadriceps tendon rupture is a rare injury, but ipsilateral simultaneous patellar and quadriceps tendon rupture was not described in the literature to our knowledge. In this article, we report a 40-year-old healthy male patient with neglected ipsilateral patellar and quadriceps tendon ruptures treated by peroneus longus tendon autograft. Patient had received some conservative and surgical treatments for patellar fracture before applying to our clinic. After our treatment using peroneus longus autograft and interference nails, patient was immobilized for six weeks in cylindrical cast. Flexion exercises and full weight bearing were started after cast removal. Patient had no complaint at postoperative second year. Patient was a neglected case. Surgical repair and early rehabilitation enabled us to achieve a satisfactory outcome.

  16. Rupture of adductor longus tendon due to ciprofloxacin. (United States)

    Mouzopoulos, George; Stamatakos, Mihalis; Vasiliadis, George; Skandalakis, Panagiotis


    We present a rare case of spontaneous rupture of the adductor longus tendon induced by ciprofloxacin. A 35-year-old man was diagnosed with pneumonia and was recommended ciprofloxacin 500 mg iv twice a day for 7 days. Three days after receiving the initial dose, he developed discomfort in his left medial thigh, and pain and swelling in the same area followed ten days later. He consulted us when he noted a palpable mass on the medial side of his left thigh, and MRI study revealed adductor longus tendon rupture. There was no obvious underlying disease or other factor causing fragility of his adductor longus tendon. We review the pathophysiological mechanisms leading to fluoroquinolone-related tendon rupture as well as the risk factors and discuss proper management.

  17. A Case of Ruptured Splenic Artery Aneurysm in Pregnancy

    Directory of Open Access Journals (Sweden)

    Elizabeth K. Corey


    Full Text Available Background. Rupture of a splenic artery aneurysm is rare complication of pregnancy that is associated with a significant maternal and fetal mortality. Case. A multiparous female presented in the third trimester with hypotension, tachycardia, and altered mental status. A ruptured splenic artery aneurysm was discovered at the time of laparotomy and cesarean delivery. The patient made a full recovery following resection of the aneurysm. The neonate survived but suffered severe neurologic impairment. Conclusion. The diagnosis of ruptured splenic artery aneurysm should be considered in a pregnant woman presenting with signs of intra-abdominal hemorrhage. Early intervention by a multidisciplinary surgical team is key to preserving the life of the mother and fetus.

  18. The temporal distribution of seismic radiation during deep earthquake rupture. (United States)

    Houston, H; Vidale, J E


    The time history of energy release during earthquakes illuminates the process of failure, which remains enigmatic for events deeper than about 100 kilometers. Stacks of teleseismic records from regional arrays for 122 intermediate (depths of 100 to 350 kilometers) and deep (depths of 350 to 700 kilometers) earthquakes show that the temporal pattern of short-period seismic radiation has a systematic variation with depth. On average, for intermediate depth events more radiation is released toward the beginning of the rupture than near the end, whereas for deep events radiation is released symmetrically over the duration of the event, with an abrupt beginning and end of rupture. These findings suggest a variation in the style of rupture related to decreasing fault heterogeneity with depth.

  19. Advancements in identifying biomechanical determinants for abdominal aortic aneurysm rupture. (United States)

    Kontopodis, Nikolaos; Metaxa, Eleni; Papaharilaou, Yannis; Tavlas, Emmanouil; Tsetis, Dimitrios; Ioannou, Christos


    Abdominal aortic aneurysms are a common health problem and currently the need for surgical intervention is determined based on maximum diameter and growth rate criteria. Since these universal variables often fail to predict accurately every abdominal aortic aneurysms evolution, there is a considerable effort in the literature for other markers to be identified towards individualized rupture risk estimations and growth rate predictions. To this effort, biomechanical tools have been extensively used since abdominal aortic aneurysm rupture is in fact a material failure of the diseased arterial wall to compensate the stress acting on it. The peak wall stress, the role of the unique geometry of every individual abdominal aortic aneurysm as well as the mechanical properties and the local strength of the degenerated aneurysmal wall, all confer to rupture risk. In this review article, the assessment of these variables through mechanical testing, advanced imaging and computational modeling is reviewed and the clinical perspective is discussed.

  20. CT Imaging Findings of Ruptured Ovarian Endometriotic Cysts: Emphasis on the Differential Diagnosis with Ruptured Ovarian Functional Cysts

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Rae [Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)


    The purpose of this study is to assess the prevalence of abnormal CT findings in patients with surgically proven ruptured endometriotic cysts, as compared with those abnormal CT findings of ruptured ovarian functional cysts. This study included 13 retrospectively identified patients with surgically confirmed ruptured ovarian endometriotic cysts and who had also undergone preoperative CT scanning during the previous seven years. As a comparative group, 25 cases of surgically confirmed ruptured ovarian functional cysts were included. We assessed the morphologic features of the cysts and the ancillary findings based on CT. For the endometriotic cysts, the mean maximum cyst diameter was significantly larger than that of the functional cysts (70.1 mm versus 36.4 mm, respectively, p < 0.05). The endometriotic cysts frequently had a multilocular shape and a thicker cyst wall, as compared to that of functional cysts, and these differences were statistically significant. Among the ancillary findings, endometriotic cysts showed a significantly higher prevalence of loculated ascites, ascites confined to the pelvic cavity without extension to the upper abdomen, and peritoneal strandings and infiltrations (p < 0.05). Although 11 of the 25 cases of functional cysts showed active extravasation of contrast material at the ovarian bleeding site, only one of 13 cases of endometriotic cysts showed active extravasation. The diagnosis of ruptured endometriotic cyst should be suspected for a woman in whom CT reveals the presence of multilocular or bilateral ovarian cysts with a thick wall and loculated ascites confined to the pelvic cavity with pelvic fat infiltrations

  1. Scale dependency of fracture energy and estimates thereof via dynamic rupture solutions with strong thermal weakening (United States)

    Viesca, R. C.; Garagash, D.


    Seismological estimates of fracture energy show a scaling with the total slip of an earthquake [e.g., Abercrombie and Rice, GJI 2005]. Potential sources for this scale dependency are coseismic fault strength reductions that continue with increasing slip or an increasing amount of off-fault inelastic deformation with dynamic rupture propagation [e.g., Andrews, JGR 2005; Rice, JGR 2006]. Here, we investigate the former mechanism by solving for the slip dependence of fracture energy at the crack tip of a dynamically propagating rupture in which weakening takes place by strong reductions of friction via flash heating of asperity contacts and thermal pressurization of pore fluid leading to reductions in effective normal stress. Laboratory measurements of small characteristic slip evolution distances for friction (~10 μm at low slip rates of μm-mm/s, possibly up to 1 mm for slip rates near 0.1 m/s) [e.g., Marone and Kilgore, Nature 1993; Kohli et al., JGR 2011] imply that flash weakening of friction occurs at small slips before any significant thermal pressurization and may thus have a negligible contribution to the total fracture energy [Brantut and Rice, GRL 2011; Garagash, AGU 2011]. The subsequent manner of weakening under thermal pressurization (the dominant contributor to fracture energy) spans a range of behavior from the deformation of a finite-thickness shear zone in which diffusion is negligible (i.e., undrained-adiabatic) to that in which large-scale diffusion obscures the existence of a thin shear zone and thermal pressurization effectively occurs by the heating of slip on a plane. Separating the contribution of flash heating, the dynamic rupture solutions reduce to a problem with a single parameter, which is the ratio of the undrained-adiabatic slip-weakening distance (δc) to the characteristic slip-on-a-plane slip-weakening distance (L*). However, for any value of the parameter, there are two end-member scalings of the fracture energy: for small slip

  2. Clinical characteristics and surgical problems of ruptured globe injury. (United States)

    Bi, Hongsheng; Cui, Yan; Li, Yang; Wang, Xingrong; Zhang, Jianhua


    Ocular trauma is a major cause of vision loss, especially in the young patients, and is the leading cause of unilateral blind in China. The aims of this report are to analyze ciliary and choroidal lesion characteristics and outcomes of a group of patients with ruptured globe injuries and discuss finding a more effective treatment protocol. Here we report our experience treating ruptured globe injuries. Seventy-five patients (75 eyes) with a diagnosis of ruptured globe injuries were selected from 264 patients with open globe injuries at the Shierming Eye Hospital of Shandong Province between January 2009 and December 2011. General information and clinical characteristics such as ciliary and choroidal lesion features were reviewed. Of the 75 patients, 85.3% were men, and the average age of the patients was 37.2 years (range, 6-63 years). The right eye was injured in 52.0%; enucleation was performed in 9 patients. There was no light perception, in the final corrected visual acuity in another 3 patients. The ratio of better visual acuity (better than 0.1) increased from 0 preoperatively to 16.0% postoperatively. Among the 75 patients with ruptured globe injuries, 13 had ciliary injury and 47 (62.7%) had choroidal injuries. Both ciliary and choroidal injuries were detected in 15 patients. Retinal tissue incarceration during sclera suturing was usually the vital point leading to unfavorable results. Ruptured globe injury usually results in severe visual acuity damage. Active treatment could help to restore visual acuity in patients to some degree. Some effective treatment protocols for ruptured globe injuries could be followed. Some unsuitable procedures in primary treatment should be avoided to achieve a better prognosis.

  3. Clinical Characteristics and Surgical Problems of Ruptured Globe Injury☆ (United States)

    Bi, Hongsheng; Cui, Yan; Li, Yang; Wang, Xingrong; Zhang, Jianhua


    Background Ocular trauma is a major cause of vision loss, especially in the young patients, and is the leading cause of unilateral blind in China. Objective The aims of this report are to analyze ciliary and choroidal lesion characteristics and outcomes of a group of patients with ruptured globe injuries and discuss finding a more effective treatment protocol. Here we report our experience treating ruptured globe injuries. Methods Seventy-five patients (75 eyes) with a diagnosis of ruptured globe injuries were selected from 264 patients with open globe injuries at the Shierming Eye Hospital of Shandong Province between January 2009 and December 2011. General information and clinical characteristics such as ciliary and choroidal lesion features were reviewed. Results Of the 75 patients, 85.3% were men, and the average age of the patients was 37.2 years (range, 6–63 years). The right eye was injured in 52.0%; enucleation was performed in 9 patients. There was no light perception, in the final corrected visual acuity in another 3 patients. The ratio of better visual acuity (better than 0.1) increased from 0 preoperatively to 16.0% postoperatively. Among the 75 patients with ruptured globe injuries, 13 had ciliary injury and 47 (62.7%) had choroidal injuries. Both ciliary and choroidal injuries were detected in 15 patients. Retinal tissue incarceration during sclera suturing was usually the vital point leading to unfavorable results. Conclusions Ruptured globe injury usually results in severe visual acuity damage. Active treatment could help to restore visual acuity in patients to some degree. Some effective treatment protocols for ruptured globe injuries could be followed. Some unsuitable procedures in primary treatment should be avoided to achieve a better prognosis. PMID:24385006

  4. Treatment of Chronic Achilles Tendon Ruptures With Large Defects. (United States)

    Ahmad, Jamal; Jones, Kennis; Raikin, Steven M


    Background When Achilles tendon ruptures become chronic, a defect often forms at the rupture site. There is scant literature regarding the treatment of chronic Achilles ruptures with defects of 6 cm or larger. We examined outcomes from combining a turndown of the proximal, central Achilles with a flexor hallucis longus (FHL) tendon transfer to treat this condition. Materials Between September 2002 and December 2013, 32 patients presented with a chronic Achilles rupture and a defect of 6 cm or more. Twenty patients were male and 12 were female. Patient age was between 20 and 74 years, with a mean of 53.3 years. Eighteen and 14 patients had their right and left Achilles tendon affected, respectively. The number of days between injury and surgery ranged from 30 to 315 days, with a mean of 102 days. Reconstruction of the Achilles involved a turndown of the proximal, central tendon and FHL augmentation. Final patient follow-up ranged from 18 to 150 months, with a mean of 62.3 months. At surgery, the gap between the ruptured ends of the Achilles ranged from 6 to 12 cm, with a mean gap of 7.5 cm. Full healing was achieved in all 32 patients (100%) by 5 months postoperatively. Mean Foot and Ankle Ability Measures scores increased from 36.3% to 90.2% between initial and latest follow-up (P Achilles ruptures with large defects are scant within the orthopaedic literature. Our method of Achilles reconstruction results in a high rate of improved function and pain relief. Therapeutic, Level IV: Case series. © 2016 The Author(s).

  5. Validation of statistical models for creep rupture by parametric analysis

    Energy Technology Data Exchange (ETDEWEB)

    Bolton, J., E-mail: [65, Fisher Ave., Rugby, Warks CV22 5HW (United Kingdom)


    Statistical analysis is an efficient method for the optimisation of any candidate mathematical model of creep rupture data, and for the comparative ranking of competing models. However, when a series of candidate models has been examined and the best of the series has been identified, there is no statistical criterion to determine whether a yet more accurate model might be devised. Hence there remains some uncertainty that the best of any series examined is sufficiently accurate to be considered reliable as a basis for extrapolation. This paper proposes that models should be validated primarily by parametric graphical comparison to rupture data and rupture gradient data. It proposes that no mathematical model should be considered reliable for extrapolation unless the visible divergence between model and data is so small as to leave no apparent scope for further reduction. This study is based on the data for a 12% Cr alloy steel used in BS PD6605:1998 to exemplify its recommended statistical analysis procedure. The models considered in this paper include a) a relatively simple model, b) the PD6605 recommended model and c) a more accurate model of somewhat greater complexity. - Highlights: Black-Right-Pointing-Pointer The paper discusses the validation of creep rupture models derived from statistical analysis. Black-Right-Pointing-Pointer It demonstrates that models can be satisfactorily validated by a visual-graphic comparison of models to data. Black-Right-Pointing-Pointer The method proposed utilises test data both as conventional rupture stress and as rupture stress gradient. Black-Right-Pointing-Pointer The approach is shown to be more reliable than a well-established and widely used method (BS PD6605).

  6. Determine Earthquake Rupture Directivity Using Taiwan TSMIP Strong Motion Waveforms (United States)

    Chang, Kaiwen; Chi, Wu-Cheng; Lai, Ying-Ju; Gung, YuanCheng


    Inverting seismic waveforms for the finite fault source parameters is important for studying the physics of earthquake rupture processes. It is also significant to image seismogenic structures in urban areas. Here we analyze the finite-source process and test for the causative fault plane using the accelerograms recorded by the Taiwan Strong-Motion Instrumentation Program (TSMIP) stations. The point source parameters for the mainshock and aftershocks were first obtained by complete waveform moment tensor inversions. We then use the seismograms generated by the aftershocks as empirical Green's functions (EGFs) to retrieve the apparent source time functions (ASTFs) of near-field stations using projected Landweber deconvolution approach. The method for identifying the fault plane relies on the spatial patterns of the apparent source time function durations which depend on the angle between rupture direction and the take-off angle and azimuth of the ray. These derived duration patterns then are compared with the theoretical patterns, which are functions of the following parameters, including focal depth, epicentral distance, average crustal 1D velocity, fault plane attitude, and rupture direction on the fault plane. As a result, the ASTFs derived from EGFs can be used to infer the ruptured fault plane and the rupture direction. Finally we used part of the catalogs to study important seismogenic structures in the area near Chiayi, Taiwan, where a damaging earthquake has occurred about a century ago. The preliminary results show a strike-slip earthquake on 22 October 1999 (Mw 5.6) has ruptured unilaterally toward SSW on a sub-vertical fault. The procedure developed from this study can be applied to other strong motion waveforms recorded from other earthquakes to better understand their kinematic source parameters.

  7. Volcanotectonic earthquakes induced by propagating dikes (United States)

    Gudmundsson, Agust


    Volcanotectonic earthquakes are of high frequency and mostly generated by slip on faults. During chamber expansion/contraction earthquakes are distribution in the chamber roof. Following magma-chamber rupture and dike injection, however, earthquakes tend to concentrate around the dike and follow its propagation path, resulting in an earthquake swarm characterised by a number of earthquakes of similar magnitudes. I distinguish between two basic processes by which propagating dikes induce earthquakes. One is due to stress concentration in the process zone at the tip of the dike, the other relates to stresses induced in the walls and surrounding rocks on either side of the dike. As to the first process, some earthquakes generated at the dike tip are related to pure extension fracturing as the tip advances and the dike-path forms. Formation of pure extension fractures normally induces non-double couple earthquakes. There is also shear fracturing in the process zone, however, particularly normal faulting, which produces double-couple earthquakes. The second process relates primarily to slip on existing fractures in the host rock induced by the driving pressure of the propagating dike. Such pressures easily reach 5-20 MPa and induce compressive and shear stresses in the adjacent host rock, which already contains numerous fractures (mainly joints) of different attitudes. In piles of lava flows or sedimentary beds the original joints are primarily vertical and horizontal. Similarly, the contacts between the layers/beds are originally horizontal. As the layers/beds become buried, the joints and contacts become gradually tilted so that the joints and contacts become oblique to the horizontal compressive stress induced by a driving pressure of the (vertical) dike. Also, most of the hexagonal (or pentagonal) columnar joints in the lava flows are, from the beginning, oblique to an intrusive sheet of any attitude. Consequently, the joints and contacts function as potential shear

  8. Setting the standards for reporting ruptured abdominal aortic aneurysm. (United States)

    Soong, Chee V; Dasari, Bobby V M; Loan, William; Hannon, Ray; Lee, Bernard; Lau, Louis; Thompson, Matthew


    Reported mortality rates for endovascular repair (EVR) of ruptured abdominal aortic aneurysm (rAAA) vary from 0% to 50%. Selection bias, inaccurate reporting, and lack of uniform reporting standards are responsible for this significant discrepancy. Existing literature about the classification/reporting systems of rAAA is reviewed. A standard way of reporting rAAA based on the physiological, radiological, and operative findings is proposed. The proposed system attempts to provide a universal language of communicating the severity of rupture, address the reporting bias, and allow comparing the outcomes of rAAA.

  9. A pregnant woman with spontaneous rupture of the uterine artery

    DEFF Research Database (Denmark)

    Jònsdòttir, Fjòla; Pinborg, Anja; Wilken-Jensen, Charlotte


    Pregnant women with acute abdominal pain are a clinical challenge. We present a rare but potential life-threatening condition of a pregnant woman with acute abdominal pain. The woman was in gestational week 37 with severe abdominal pain and was admitted to the labour ward. She became haemo......-dynamic instable 24 hours after vaginal delivery, and emergency laparotomi revealed a spontaneous rupture of the right uterine artery. Spontaneous rupture of the uterine artery is rare but should be considered as a possible cause of acute abdominal pain in pregnant women....

  10. Deflate-gate: Conservative Management of a Large Ruptured Hydrocele

    Directory of Open Access Journals (Sweden)

    Viktor X. Flores


    Full Text Available A hydrocele is a common cause of intrascrotal swelling that results when fluid accumulates between the parietal and visceral layers of the tunica vaginalis. Over time, fluid may collect to form a massive hydrocele and result in significant discomfort for the patient. In this case report, we present a rare event of a 28-year-old gentleman with a documented massive hydrocele measuring 14.1 × 8.9 cm who ruptured his hydrocele during sexual intercourse. We expectantly managed the patient's ruptured hydrocele and encountered no complications throughout the course of his recovery.

  11. Deflate-gate: Conservative Management of a Large Ruptured Hydrocele. (United States)

    Flores, Viktor X; Wallen, Jared J; Martinez, Danny R; Carrion, Rafael


    A hydrocele is a common cause of intrascrotal swelling that results when fluid accumulates between the parietal and visceral layers of the tunica vaginalis. Over time, fluid may collect to form a massive hydrocele and result in significant discomfort for the patient. In this case report, we present a rare event of a 28-year-old gentleman with a documented massive hydrocele measuring 14.1 × 8.9 cm who ruptured his hydrocele during sexual intercourse. We expectantly managed the patient's ruptured hydrocele and encountered no complications throughout the course of his recovery.

  12. Spontaneous rupture of intrahepatic biliary ducts with biliary peritonitis. (United States)

    Aydin, Unal; Yazici, Pinar; Coker, Ahmet


    Spontaneous rupture of intrahepatic biliary ducts is a rare cause of acute abdomen due to biliary peritonitis. We report a 92-year-old woman with 48-h history of upper abdominal pain, nausea and vomiting and peritoneal signs. CT scan showed free fluid in the abdomen and mild dilatation of the common bile duct. Exploratory laparotomy showed bile in the abdominal cavity with leak-age from a ruptured bile duct radicle in segment 3, as confirmed on intraoperative cholangiography. She underwent cholecystectomy, choledochotomy with removal of gallstones, repair of the perforation with primary suture and placement of a T-tube. She had an uneventful recovery.

  13. Aneurysmal re-rupture during selective cerebral angiography

    Energy Technology Data Exchange (ETDEWEB)

    Zaehringer, Markus; Gossmann, Axel; Krueger, Karsten; Trenschel, Gertrud; Landwehr, Peter [Department of Radiology, University of Cologne, Joseph-Stelzmann-Strasse 9, 50924 Cologne (Germany); Wedekind, Christoph [Department of Neurosurgery, University of Cologne, Joseph-Stelzmann-Strasse 9, 50924 Cologne (Germany)


    Two cases of aneurysmal re-rupture during intracranial angiography are presented. This event is accompanied by disastrous consequences with regard to the clinical condition of the patient, as is evident from the cases presented as well as from the literature. Acute alterations of intraluminal pressure as well as a time interval of less than 6 h seems to increase the risk of re-bleeding during angiography. The introduction of and the growing experience with CT and MR angiography may in the near future provide sufficient diagnostic information for surgical planning and thus help to overcome the risk of aneurysmal re-rupture during intra-arterial angiography. (orig.)

  14. Survival after blunt left ventricular rupture with cardiac tamponade

    Institute of Scientific and Technical Information of China (English)

    Yu-Jang Su; Chang-Chih Chen


    A34-year-old man was drunk and drove to hit a traffic island.Cold sweating and unconscious status were found on arrival.Vital signs revealedBP42/25, and heart rate121/min.There was massive pericardial effusion with cardiac tamponade found byCT.Immediate surgical intervention and rupture of left ventricular(LV) free wall was found.He was discharged after2 d intensive care unit(ICU) observation and5-day regular ward care.There is high mortality rate in traumatic heart rupture although timely repair, over all mortality is around20%-36% in recent3 years.

  15. Survival after blunt left ventricular rupture with cardiac tamponade

    Directory of Open Access Journals (Sweden)

    Yu-Jang Su


    Full Text Available A 34-year-old man was drunk and drove to hit a traffic island. Cold sweating and unconscious status were found on arrival. Vital signs revealed BP 42/25, and heart rate 121/min. There was massive pericardial effusion with cardiac tamponade found by CT. Immediate surgical intervention and rupture of left ventricular (LV free wall was found. He was discharged after 2 d intensive care unit (ICU observation and 5-day regular ward care. There is high mortality rate in traumatic heart rupture although timely repair, over all mortality is around 20%-36% in recent 3 years.

  16. Prepatellar continuation rupture: Report of an unusual case. (United States)

    Majeed, Haroon; dos Remedios, Ian; Datta, Praveen; Griffiths, David


    In anatomical studies the deepest soft tissue layer, related to the deep rectus femoris tendinous fibers, has been described as the "prepatellar quadriceps continuation". We present an unusual case of an isolated prepatellar continuation rupture, which to our knowledge is the first described case in the literature. Injuries to the extensor mechanism may include isolated rupture of the prepatellar continuation with intact quadriceps and patellar tendons. Diagnosis may be difficult with ultrasound scan and requires MRI scan for confirmation. Appropriate clinical assessment and regular physiotherapy lead to a full functional recovery.

  17. Seat belt trauma: pectoralis muscle rupture and delayed mesh repair. (United States)

    Harvey, Kyle P; Adair, James D; Ali, M Azhar


    To our knowledge, this is the first reported case of a seat belt-related rupture of the pectoralis major muscle and its successful delayed repair using mesh. We report a case of a 34-year-old white man who sustained a right pectoralis major muscle rupture from a seat belt during a motor vehicle crash. The patient presented to us 2 years after the injury. We introduce a technique using mesh that results in a successful repair of a cosmetically disfiguring chest wall defect.

  18. Rupture of an expander prosthesis mimics axillary cancer recurrence.

    LENUS (Irish Health Repository)

    Ismael, T


    Regional silicone gel migration from a ruptured breast implant has been reported at different locations including the upper extremity, chest wall muscles, axilla and back. We report a patient who presented with an axillary mass that mimicked a regional recurrence 5 years after breast cancer reconstruction with a latissimus dorsi musculocutaneous flap and silicon gel expander-prosthesis. Surgical exploration revealed that the mass contained silicone gel around the port of the breast expander that had ruptured. The mass was confluent with an intracapsular silicone leak through a tract along the tube of the expander port.

  19. Intra-Aortic Balloon Pump Rupture and Entrapment

    Directory of Open Access Journals (Sweden)

    Artan Jahollari


    Full Text Available Intra-aortic balloon pump is used frequently to support a failing myocardium in cardiac patients. Due to the invasive nature of this device, usage is accompanied by consistent risk of complications. Balloon rupture, although it occurs rarely, may lead to entrapment if diagnosis delays. A 78-year male who underwent cardiac surgery experienced balloon rupture and entrapment in the right femoral artery during the postoperative follow-up. Surgical extraction under local anesthesia was performed and the patient had an uneventful course. Fast and gentle solution of the problem is necessary to prevent further morbidity or mortality related to a retained balloon catheter in these delicate patients.

  20. Detailed Surface Rupture Geometry from the 2016 Amatrice Earthquake (United States)

    Mildon, Z. K.; Iezzi, F.; Wedmore, L. N. J.; Gregory, L. C.; McCaffrey, K. J. W.; Wilkinson, M. W.; Faure Walker, J.; Roberts, G.; Livio, F.; Vittori, E.; Michetti, A.; Frigerio, C.; Ferrario, F.; Blumetti, A. M.; Guerrieri, L.; Di Manna, P.; Comerci, V.


    The Amatrice earthquake was generated by co-rupture of the Mt. Vettore and Laga faults at depth. Surface ruptures were observed for 5km along the Mt. Vettore fault, with no clear observations on the Laga fault reported to date. The surface rupture on Mt. Vettore manifests as a 15-20cm pale stripe at the base of a 60-80o dipping bedrock fault scarp and similar magnitude vertical offsets of colluvial deposits. We have measured the strike and dip of the fault alongside the coseismic throw, heave, and slip azimuth along the length of the rupture with high spatial resolution (c.2-6m, >2000 measurements). The slip azimuth is relatively constant between 210-270° even where the rupture faces uphill at its SE termination which is consistent with the regional NW-SE extension direction, defined by focal mechanisms and borehole break-out data. The simplest coseismic throw profile that would be expected is quasi-symmetric. However we found the highest values of throw (Inter Quartile Range 15-19.5cm) are skewed towards the NW end on a 1.7 km section of the fault that is oblique relative to the overall fault strike. In the centre of the rupture, orientated close to the overall fault strike, the throw is lower (IQR 7.5-13cm) and discontinuous along strike. We suggest that the skewed throw profile occurs because the strike, dip and throw must vary systematically in order to preserve the principal strain rate across a fault, in agreement with previous publications. The density of our measurements, crucially including the slip azimuth, allows us to resolve the regional debate over whether normal fault ruptures are primary tectonic features or landslides of hangingwall sediments. If the surface offsets are due to landslides, then the slip azimuth should correlate with the downslope direction of the hangingwall. We show using an available 10m DEM that this is not the case and hence the surface offsets described herein are a primary tectonic feature. This presentation offers new

  1. Traumatic rupture of the stomach after Heimlich maneuver. (United States)

    van der Ham, A C; Lange, J F


    Fatal complications following the performance of the Heimlich maneuver have been reported. A 76-year-old woman presented to the emergency department with signs of respiratory distress, abdominal pain and distension one day after airway obstruction and subsequent resuscitation. Despite successful immediate laparotomy and repair of a ruptured stomach, she later succumbed to the sequelae of aspiration of gastric contents and dehiscence of the gastric tear. This is the 4th case of stomach rupture and the 7th reported fatal complication following the Heimlich maneuver. It is recommended that persons who undergo the Heimlich maneuver be examined and observed by a physician, as soon as possible, to rule out complications.

  2. Stability and rupture of archaebacterial cell membrane: a model study. (United States)

    Li, Shuangyang; Zheng, Fengxian; Zhang, Xianren; Wang, Wenchuan


    It is known that the thermoacidophilic archaebacterium Sulfolobus acidocaldarius can grow in hot springs at 65-80 degrees C and live in acidic environments (pH 2-3); however, the origin of its unusual thermal stability remains unclear. In this work, using a vesicle as a model, we study the thermal stability and rupture of archaebacterial cell membrane. We perform a simulation investigation of the structure-property relationship of monolayer membrane formed by bolaform lipids and compare it with that of bilayer membrane formed by monopolar lipids. The origin of the unusually thermal stability of archaebacterial cell and the mechanism for its rupture are presented in molecular details.

  3. Spontaneous rupture of thymic neuroendocrine carcinoma: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan Yeong; Lee, In Jae; Min, Soo Kee [Hallym University College of Medicine, Chuncheon (Korea, Republic of)


    Thymic neuroendocrine carcinoma (NEC) is a rare neoplasm with tendencies of local invasion and metastasis. Usually, it is detected incidentally or by its symptoms caused by mass effect. Rupture of the tumor is extremely rare. In this study, we report a case of a ruptured thymic NEC that was combined with a potentially fatal hemorrhage. This lesion was manifested as a progressive bulging of the right cardiac border on serial chest radiographs, and on CT as a large anterior mediastinal mass with heterogeneous enhancement, internal necrosis, and hematoma.

  4. Left ventricular rupture postmitral valve replacement: Surviving a catastrophe

    Directory of Open Access Journals (Sweden)

    Samarjit Bisoyi


    Full Text Available One of the dreaded mechanical complications of mitral valve replacement (MVR is rupture of the left ventricle (LV. This report describes the early diagnosis and successful repair of rupture of posterior wall of LV in an elderly patient who underwent MVR. We have discussed the risk factors and perioperative issues implicated in such complication. The anesthesiologist as an intra-operative echocardiographer can aid in identifying the patient at risk. Though important surgical steps are necessary to prevent the complication; nonetheless, the anesthesiologist needs to take key measures in the perioperative period.

  5. Endovascular coil oclusion of spontaneous ruptured vertebral artery dissecting aneurysm

    Directory of Open Access Journals (Sweden)

    Chiriac A.


    Full Text Available Spontaneous dissecting aneurysm of vertebral artery is known as a rare pathological condition causing a subarachnoid hemorrhage in the posterior circulation. The treatment of ruptured vertebral artery dissecting aneurysms is still an important subject of debates in the literature. We present a particular case of ruptured vertebral artery dissecting aneurysms that was treated by only endovascular Guglielmi detachable coils occlusion. A brief review of technical possibilities of treatment of these types of vascular lesions, with their advantages and disadvantages are discussed.

  6. 3D Spontaneous Rupture Models of Large Earthquakes on the Hayward Fault, California (United States)

    Barall, M.; Harris, R. A.; Simpson, R. W.


    We are constructing 3D spontaneous rupture computer simulations of large earthquakes on the Hayward and central Calaveras faults. The Hayward fault has a geologic history of producing many large earthquakes (Lienkaemper and Williams, 2007), with its most recent large event a M6.8 earthquake in 1868. Future large earthquakes on the Hayward fault are not only possible, but probable (WGCEP, 2008). Our numerical simulation efforts use information about the complex 3D fault geometry of the Hayward and Calaveras faults and information about the geology and physical properties of the rocks that surround the Hayward and Calaveras faults (Graymer et al., 2005). Initial stresses on the fault surface are inferred from geodetic observations (Schmidt et al., 2005), seismological studies (Hardebeck and Aron, 2008), and from rate-and- state simulations of the interseismic interval (Stuart et al., 2008). In addition, friction properties on the fault surface are inferred from laboratory measurements of adjacent rock types (Morrow et al., 2008). We incorporate these details into forward 3D computer simulations of dynamic rupture propagation, using the FaultMod finite-element code (Barall, 2008). The 3D fault geometry is constructed using a mesh-morphing technique, which starts with a vertical planar fault and then distorts the entire mesh to produce the desired fault geometry. We also employ a grid-doubling technique to create a variable-resolution mesh, with the smallest elements located in a thin layer surrounding the fault surface, which provides the higher resolution needed to model the frictional behavior of the fault. Our goals are to constrain estimates of the lateral and depth extent of future large Hayward earthquakes, and to explore how the behavior of large earthquakes may be affected by interseismic stress accumulation and aseismic slip.

  7. Dynamic rupture simulations on complex fault zone structures with off-fault plasticity using the ADER-DG method (United States)

    Wollherr, Stephanie; Gabriel, Alice-Agnes; Igel, Heiner


    In dynamic rupture models, high stress concentrations at rupture fronts have to to be accommodated by off-fault inelastic processes such as plastic deformation. As presented in (Roten et al., 2014), incorporating plastic yielding can significantly reduce earlier predictions of ground motions in the Los Angeles Basin. Further, an inelastic response of materials surrounding a fault potentially has a strong impact on surface displacement and is therefore a key aspect in understanding the triggering of tsunamis through floor uplifting. We present an implementation of off-fault-plasticity and its verification for the software package SeisSol, an arbitrary high-order derivative discontinuous Galerkin (ADER-DG) method. The software recently reached multi-petaflop/s performance on some of the largest supercomputers worldwide and was a Gordon Bell prize finalist application in 2014 (Heinecke et al., 2014). For the nonelastic calculations we impose a Drucker-Prager yield criterion in shear stress with a viscous regularization following (Andrews, 2005). It permits the smooth relaxation of high stress concentrations induced in the dynamic rupture process. We verify the implementation by comparison to the SCEC/USGS Spontaneous Rupture Code Verification Benchmarks. The results of test problem TPV13 with a 60-degree dipping normal fault show that SeisSol is in good accordance with other codes. Additionally we aim to explore the numerical characteristics of the off-fault plasticity implementation by performing convergence tests for the 2D code. The ADER-DG method is especially suited for complex geometries by using unstructured tetrahedral meshes. Local adaptation of the mesh resolution enables a fine sampling of the cohesive zone on the fault while simultaneously satisfying the dispersion requirements of wave propagation away from the fault. In this context we will investigate the influence of off-fault-plasticity on geometrically complex fault zone structures like subduction

  8. Parametrization of Fully Dressed Quark Propagator

    Institute of Scientific and Technical Information of China (English)

    MA Wei-Xing; ZHU Ji-Zhen; ZHOU Li-Juan; SHEN Peng-Nian; HU Zhao-Hui


    Based on an extensive study of the Dyson-Schwinger equations for a fully dressed quark propagator in the "rainbow" approximation, a parametrized form of the quark propagator is suggested. The corresponding quark selfform of the quark propagator proposed in this work describes a confining quark propagation, and is quite convenient to be used in any numerical calculations.

  9. Coseismic temporal changes of slip direction: the effect of absolute stress on dynamic rupture (United States)

    Guatteri, Mariagiovanna; Spudich, P.


    We investigate the dynamics of rupture at low-stress level. We show that one main difference between the dynamics of high- and low-stress events is the amount of coseismic temporal rake rotation occurring at given points on the fault. Curved stations on exposed fault surfaces and earthquake dislocation models derived from ground-motion inversion indicate that the slip direction may change with time at a pointon the fault during dynamic rupture. We use a 3D boundary integral method to model temporal rake variations during dynamic rupture propagation assuming a slip-weakening friction law and isotropic friction. The points at which the slip rotates most are characterized by an initial shear stress direction substantially different from the average stress direction over the fault plane. We show that for a given value of stress drop, the level of initial shear stress (i.e., the fractional stress drop) determines the amount of rotation in slip direction. We infer that seismic events that show evidence of temporal rake rorations are characterized by a low initial shear-stress level with spatially variable direction on the fault (possibly due to changes in fault surface geometry) and an almost complete stress drop. Our models motivate a new interpretation of curved and cross-cutting striations and put new constraints on their analysis. The initial rake is in general collinear with the initial stress at the hypocenter zone, supporting the assumptions made in stress-tensor inversion from first-motion analysis. At other points on the fualt, especially away from the hypocenter, the initial slip rake may not be collinear with the initial shear stress, contradicting a common assumption of structural geology. On the other hand, the later part of slip in our models is systematically more aligned withi the average stress direction than the early slip. Our modeling suggests that the length of the straight part of curved striations is usually an upper bound of the slip

  10. Survey of propagation Model in wireless Network

    Directory of Open Access Journals (Sweden)

    Hemant Kumar Sharma


    Full Text Available To implementation of mobile ad hoc network wave propagation models are necessary to determine propagation characteristic through a medium. Wireless mobile ad hoc networks are self creating and self organizing entity. Propagation study provides an estimation of signal characteristics. Accurate prediction of radio propagation behaviour for MANET is becoming a difficult task. This paper presents investigation of propagation model. Radio wave propagation mechanisms are absorption, reflection, refraction, diffraction and scattering. This paper discuss free space model, two rays model, and cost 231 hata and its variants and fading model, and summarized the advantages and disadvantages of these model. This study would be helpful in choosing the correct propagation model.

  11. The FLIC Overlap Quark Propagator

    CERN Document Server

    Kamleh, W; Leinweber, D B; Williams, A G; Zhang, J; Kamleh, Waseem; Bowman, Patrick O.; Leinweber, Derek B.; Williams, Anthony G.; Zhang, Jianbo


    FLIC overlap fermions are a variant of the standard (Wilson) overlap action, with the FLIC (Fat Link Irrelevant Clover) action as the overlap kernel rather than the Wilson action. The structure of the FLIC overlap fermion propagator in momentum space is studied, and a comparison against previous studies of the Wilson overlap propagator in quenched QCD is performed. To explore the scaling properties of the propagator for the two actions, numerical calculations are performed in Landau Gauge across three lattices with different lattice spacing $a$ and similar physical volumes. We find that at light quark masses the acti ons agree in both the infrared and the ultraviolet, but at heavier masses some disagreement in the ultraviolet appears. This is attributed to the two action s having different discretisation errors with the FLIC overlap providing superior performance in this regime. Both actions scale reasonably, but some scaling violations are observed.

  12. Wave propagation in ballistic gelatine. (United States)

    Naarayan, Srinivasan S; Subhash, Ghatu


    Wave propagation characteristics in long cylindrical specimens of ballistic gelatine have been investigated using a high speed digital camera and hyper elastic constitutive models. The induced transient deformation is modelled with strain rate dependent Mooney-Rivlin parameters which are determined by modelling the stress-strain response of gelatine at a range of strain rates. The varying velocity of wave propagation through the gelatine cylinder is derived as a function of prestress or stretch in the gelatine specimen. A finite element analysis is conducted using the above constitutive model by suitably defining the impulse imparted by the polymer bar into the gelatine specimen. The model results are found to capture the experimentally observed wave propagation characteristics in gelatine effectively.

  13. Propagating Class and Method Combination

    DEFF Research Database (Denmark)

    Ernst, Erik


    This paper presents a mixin based class and method combination mechanism with block structure propagation. Traditionally, mixins can be composed to form new classes, possibly merging the implementations of methods (as in CLOS). In our approach, a class or method combination operation may cause any...... number of implicit combinations. For example, it is possible to specify separate aspects of a family of classes, and then combine several aspects into a full-fledged class family. The combination expressions would explicitly combine whole-family aspects, and by propagation implicitly combine the aspects...... for each member of the class family, and again by propagation implicitly compose each method from its aspects. As opposed to CLOS, this is type-checked statically; and as opposed to other systems for advanced class combination/ merging/weaving, it is integrated directly in the language, ensuring a clear...

  14. Gluon propagator with dynamical quarks

    CERN Document Server

    Papavassiliou, Joannis


    We review recent work on the effects of quark loops on the gluon propagator in the Landau gauge, relying mainly on the Schwinger-Dyson equations that describe the two-point sector of QCD. Particularly important in this context is the detailed study of how the standard gluon mass generation mechanism, which is responsible for the infrared finiteness of the quenched gluon propagator, is affected by the inclusions of dynamical quarks. This issue is especially relevant and timely, given the qualitative picture that emerges from recent unquenched lattice simulations. Our results demonstrate clearly that the gluon mass generation persists, and that the corresponding saturation points of the unquenched gluon propagators are progressively suppressed, as the number of quark flavors increases.

  15. Wave equations for pulse propagation

    Energy Technology Data Exchange (ETDEWEB)

    Shore, B.W.


    Theoretical discussions of the propagation of pulses of laser radiation through atomic or molecular vapor rely on a number of traditional approximations for idealizing the radiation and the molecules, and for quantifying their mutual interaction by various equations of propagation (for the radiation) and excitation (for the molecules). In treating short-pulse phenomena it is essential to consider coherent excitation phenomena of the sort that is manifest in Rabi oscillations of atomic or molecular populations. Such processes are not adequately treated by rate equations for excitation nor by rate equations for radiation. As part of a more comprehensive treatment of the coupled equations that describe propagation of short pulses, this memo presents background discussion of the equations that describe the field. This memo discusses the origin, in Maxwell's equations, of the wave equation used in the description of pulse propagation. It notes the separation into lamellar and solenoidal (or longitudinal and transverse) and positive and negative frequency parts. It mentions the possibility of separating the polarization field into linear and nonlinear parts, in order to define a susceptibility or index of refraction and, from these, a phase and group velocity. The memo discusses various ways of characterizing the polarization characteristics of plane waves, that is, of parameterizing a transverse unit vector, such as the Jones vector, the Stokes vector, and the Poincare sphere. It discusses the connection between macroscopically defined quantities, such as the intensity or, more generally, the Stokes parameters, and microscopic field amplitudes. The material presented here is a portion of a more extensive treatment of propagation to be presented separately. The equations presented here have been described in various books and articles. They are collected here as a summary and review of theory needed when treating pulse propagation.

  16. Impact of Partial and complete rupture of anterior cruciate ligament on medial meniscus: A cadavaric study

    Directory of Open Access Journals (Sweden)

    Wei Jiang


    Conclusions: Similar to complete rupture, partial rupture of ACL can also trigger strain concentration on medial meniscus, especially posterior horn, which may be a more critical reason for meniscus injury associated with chronic ACL deficiency.

  17. Ruptured spinal arteriovenous malformation: Presenting as stunned myocardium and neurogenic shock

    Directory of Open Access Journals (Sweden)

    Tasneem H Mehesry


    Conclusions: Spinal AVM rupture can present as neurogenic shock, stunned myocardium, and pulmonary edema. Early recognition of AVM rupture and prompt surgical intervention, as well as aggressive treatment of shock, may enhance recovery and decrease the long-term morbidity.

  18. Spontaneous Rupture of Pheochromocytoma: Computed Tomography-Pathologic Features and Correlation

    Energy Technology Data Exchange (ETDEWEB)

    Park, B.K.; Kim, C.K.; Kwon, G.Y. (Dept. of Radiology and Center for Imaging Science, and Dept. of Pathology, Samsung Medical Center, Sungkyunkwan Univ. School of Medicine, Seoul (KR))


    Spontaneous rupture is a rare complication of pheochromocytoma. Its preoperative diagnosis is of great importance in determining treatment and prognosis. We describe computed tomography pathologic findings and correlate their features in a case with ruptured pheochromocytoma

  19. Propagation of stress corrosion cracks in alpha-brasses

    Energy Technology Data Exchange (ETDEWEB)

    Beggs, Dennis Vinton [Univ. of Illinois, Urbana-Champaign, IL (United States)


    Transgranular and intergranular stress corrosion cracks were investigated in alpha-brasses in a tarnishing ammoniacal solution. Surface observation indicated that the transgranular cracks propagated discontinuously by the sudden appearance of a fine crack extending several microns ahead of the previous crack tip, often associated with the detection of a discrete acoustic emission (AE). By periodically increasing the deflection, crack front markings were produced on the resulting fracture surfaces, showing that the discontinuous propagation of the crack trace was representative of the subsurface cracking. The intergranular crack trace appeared to propagate continuously at a relatively blunt crack tip and was not associated with discrete AE. Under load pulsing tests with a time between pulses, Δt greater than or equal to 3 s, the transgranular fracture surfaces always exhibited crack front markings which corresponded with the applied pulses. The spacing between crack front markings, Δx, decreased linearly with Δt. With Δt less than or equal to 1.5 s, the crack front markings were in a one-to-one correspondence with applied pulses only at relatively long crack lengths. In this case, Δx = Δx* which approached a limiting value of 1 μm. No crack front markings were observed on intergranular fracture surfaces produced during these tests. It is concluded that transgranular cracking occurs by discontinuous mechanical fracture of an embrittled region around the crack tip, while intergranular cracking results from a different mechanism with cracking occurring via the film-rupture mechanism.

  20. Vegetative propagation of Bambusa vulgaris

    Directory of Open Access Journals (Sweden)

    Rafael Malfitano Braga


    Full Text Available Bamboo is an important source of raw material of multiple uses. The development of simple techniques for its propagation is a practical way to enable its implementation in ownership of low technology. The present work had the objective of evaluating artisanal propagation methods for Bambusa vulgaris. Two types of propagules were tested, with buds budded or not, and three relative positions to the removal of vegetative material on the culm. The best propagule was with only one node, extracted from the lower thirds of the stem, presenting 72% of rooting. This result demonstrates its potential for seedling production of this species under low tech.

  1. SIS epidemic propagation on hypergraphs

    CERN Document Server

    Bodó, Ágnes; Simon, Péter L


    Mathematical modeling of epidemic propagation on networks is extended to hypergraphs in order to account for both the community structure and the nonlinear dependence of the infection pressure on the number of infected neighbours. The exact master equations of the propagation process are derived for an arbitrary hypergraph given by its incidence matrix. Based on these, moment closure approximation and mean-?eld models are introduced and compared to individual-based stochastic simulations. The simulation algorithm, developed for networks, is extended to hypergraphs. The e?ects of hypergraph structure and the model parameters are investigated via individual-based simulation results.

  2. Traumatic ruptured globe eye injuries in a large urban center. (United States)

    Burstein, Eitan S; Lazzaro, Douglas R


    The purpose of this study was to examine patient characteristics and outcomes in a group of consecutive patients with ruptured globe eye injuries at Kings County Hospital Center, a large, urban, level 1 trauma center. A retrospective chart review was performed to identify all patients with ruptured globe eye injuries seen between January 2009 and October 2011. Thirty-eight patients who sustained ruptured globe eye injuries from all causes were investigated for etiology and final visual outcomes. Eight eyes in which vision could be assessed were evaluated as having no light perception at presentation and three of these eyes required primary enucleation. Of the 38 eyes, orbit fractures were found in 15 eyes and an intraocular foreign body was found in six eyes. Our cohort revealed a 37.5% rate of primary enucleation in eyes with no light perception, which we believe to be a reflection of the severity of injury. All three cases were secondary to a gunshot wound. Further, our sample, although small in size, revealed a very high percentage of eyes that were ruptured secondary to violent causes compared with other studies.

  3. Rupture uterus: changing trends in etiology and management.

    Directory of Open Access Journals (Sweden)

    Nagarkatti R


    Full Text Available Sixty-four cases of rupture uterus which occurred during the period 1980-89 were studied and compared with 70 cases in the preceding decade (1970-79. The changing trends in etiological factors and management of this condition have been demonstrated. While spontaneous rupture continued to account for about two-thirds of the cases (70.3%, the incidence of traumatic rupture uterus has become less than half, from 17.1 to 7.8%, and that of scar rupture has increased to more than double (from 11.4 to 23.4%. As regards management, there are improved results seen with conservative repair of the uterus. It was also seen that a subtotal hysterectomy was more commonly resorted to than total hysterectomy in the later decade. There was a decrease in the overall morbidity from 42.8 to 35.9% and also in the mortality rate from 24.3 to 18.7%.

  4. Use of ICD-10 codes to monitor uterine rupture

    DEFF Research Database (Denmark)

    Thisted, Dorthe L A; Mortensen, Laust Hvas; Hvidman, Lone


    . We retrieved the medical records of all women in the MBR with a code for uterine rupture during labor regardless of whether or not a prior cesarean section had been reported to the registry. In addition medical records of all women with a code for previous cesarean section and delivery of a child...

  5. Clinical recovery of two hip adductor longus ruptures

    DEFF Research Database (Denmark)

    Thorborg, Kristian; Petersen, Jesper; Nielsen, Michael Bachmann


    BACKGROUND: Non-operative treatment of acute hip adductor longus ruptures in athletes has been described in the literature. However, very limited information concerning the recovery of this type of injury exists. This case represented a unique possibility to study the recovery of two acute adduct...

  6. Outcomes of Endovascular Repair of Ruptured Descending Thoracic Aortic Aneurysms

    NARCIS (Netherlands)

    Jonker, Frederik H. W.; Verhagen, Hence J. M.; Lin, Peter H.; Heijmen, Robin H.; Trimarchi, Santi; Lee, W. Anthony; Moll, Frans L.; Athamneh, Husam; Muhs, Bart E.


    Background-Thoracic endovascular aortic repair offers a less invasive approach for the treatment of ruptured descending thoracic aortic aneurysms (rDTAA). Due to the low incidence of this life-threatening condition, little is known about the outcomes of endovascular repair of rDTAA and the factors t

  7. Outcomes of endovascular repair of ruptured descending thoracic aortic aneurysms

    NARCIS (Netherlands)

    F.H.W. Jonker; H.J.M. Verhagen (Hence); P.H. Lin (Peter); R.H. Heijmen (Robin); S. Trimarchi (Santi); W.A. Lee (Anthony); F.L. Moll (Frans); H. Athamneh (Husam); B.E. Muhs (Bart)


    textabstractBackground-: Thoracic endovascular aortic repair offers a less invasive approach for the treatment of ruptured descending thoracic aortic aneurysms (rDTAA). Due to the low incidence of this life-threatening condition, little is known about the outcomes of endovascular repair of rDTAA and

  8. Anthrax toxin-induced rupture of artificial lipid bilayer membranes (United States)

    Nablo, Brian J.; Panchal, Rekha G.; Bavari, Sina; Nguyen, Tam L.; Gussio, Rick; Ribot, Wil; Friedlander, Art; Chabot, Donald; Reiner, Joseph E.; Robertson, Joseph W. F.; Balijepalli, Arvind; Halverson, Kelly M.; Kasianowicz, John J.


    We demonstrate experimentally that anthrax toxin complexes rupture artificial lipid bilayer membranes when isolated from the blood of infected animals. When the solution pH is temporally acidified to mimic that process in endosomes, recombinant anthrax toxin forms an irreversibly bound complex, which also destabilizes membranes. The results suggest an alternative mechanism for the translocation of anthrax toxin into the cytoplasm.

  9. Surgical repair of subacute left ventricular free wall rupture

    NARCIS (Netherlands)

    Zeebregts, CJ; Noyez, L; Hensens, AG; Skotnicki, SH; Lacquet, LK


    Background: The natural course of subacute ventricular free wall rupture (FWR) as a complication of acute myocardial infarction (MI) is usually lethal. The aim of this study was to investigate the curability of this entity and to report on five patients successfully treated by rapid diagnosis, hemod


    Directory of Open Access Journals (Sweden)

    Mercy Rodrigo


    Full Text Available BACKGROUND The objectives of this study are 1 To find out the incidence of premature rupture of membranes, 2 To evaluate the aetiology of premature rupture of membranes, 3 To assess foetal and maternal outcome in premature rupture of membranes. MATERIAL AND METHODS This prospective case control study was conducted in Govt. RSRM Lying In Hospital, Chennai, over a period of 6 months and 100 cases of spontaneous rupture of membranes attending the Department of Obstetrics and Gynaecology were studied. Maternal and neonatal outcome were compared with controls. RESULTS Incidence of PROM was 9.06%. Most of them belonged to low socioeconomic class and in the age group 20-29 years, commonly seen primi gravida and in unbooked cases. Aetiological analysis revealed infection in 15% of cases, which is evident by positive amniotic fluid culture, h/o recent coitus in 20%, mal-presentation in 7%. Cause is unknown in most of the cases. The caesarean section rate is 24% when compared to 12% in control group. The PROM group had higher morbidities like postpartum haemorrhage, postpartum fever, wound infection, neonatal sepsis. CONCLUSION This study showed significantly increased morbidity for both mother and baby. PROM causes major increase in the incidence of prematurity, hence careful screening of high risk factors and treatment of infection promptly is needed to decrease the perinatal morbidity and mortality.

  11. Complex rupture during the 12 January 2010 Haiti earthquake (United States)

    Hayes, G.P.; Briggs, R.W.; Sladen, A.; Fielding, E.J.; Prentice, C.; Hudnut, K.; Mann, P.; Taylor, F.W.; Crone, A.J.; Gold, R.; Ito, T.; Simons, M.


    Initially, the devastating Mw 7.0, 12 January 2010 Haiti earthquake seemed to involve straightforward accommodation of oblique relative motion between the Caribbean and North American plates along the Enriquillog-Plantain Garden fault zone. Here, we combine seismological observations, geologic field data and space geodetic measurements to show that, instead, the rupture process may have involved slip on multiple faults. Primary surface deformation was driven by rupture on blind thrust faults with only minor, deep, lateral slip along or near the main Enriquillog-Plantain Garden fault zone; thus the event only partially relieved centuries of accumulated left-lateral strain on a small part of the plate-boundary system. Together with the predominance of shallow off-fault thrusting, the lack of surface deformation implies that remaining shallow shear strain will be released in future surface-rupturing earthquakes on the Enriquillog-Plantain Garden fault zone, as occurred in inferred Holocene and probable historic events. We suggest that the geological signature of this earthquakeg-broad warping and coastal deformation rather than surface rupture along the main fault zoneg-will not be easily recognized by standard palaeoseismic studies. We conclude that similarly complex earthquakes in tectonic environments that accommodate both translation and convergenceg-such as the San Andreas fault through the Transverse Ranges of Californiag-may be missing from the prehistoric earthquake record. ?? 2010 Macmillan Publishers Limited. All rights reserved.

  12. Treatment of A Case of Spontaneous Rupture of Achille's Tendon

    Institute of Scientific and Technical Information of China (English)



    @@ Mr. Guo, 51 years old, paid his first visit on November 7, 2001. The patient felt sudden pain in the right Achille's tendon in June 1999 with no apparent predisposing factors. Several months later he palpated a small pitting in the middle of the right Achille's tendon, which expanded gradually in size. In June 2000, two thirds of the tendon was diagnosed to be ruptured in a local hospital. Ten days later the tendon was ruptured completely when he felt sudden severe pain, numbness and distention, and he was unable to raise the heel. The lesion was healed three months later after being treated with a plaster model, but it was partially ruptured again 6 months later. Though the ruptured tendon was healed again with the help of a plaster model, he still suffered from local swelling and pain, which was aggravated during movement and made him difficult in walking, squatting down and standing up. During the examination, the right heel was found hyperemic and swollen with ecchymosis and tenderness. The tongue proper was dark red and the pulse thready and rapid. The condition was due to depletion and deficiency of liver-qi, stagnant blood with dampheat obstructing the collaterals. The principle of nourishing the liver and soothing the tendon was adopted, assisted by invigorating blood circulation and removing blood stasis, clearing heat and transforming dampness.

  13. Acute Achilles tendon rupture Treatment strategies and outcomes

    NARCIS (Netherlands)

    Metz, R.


    Based on the results of the studies presented in this thesis it is concluded that minimally invasive surgical treatment of acute AT ruptures with functional after-treatment allows patients to return to their original level of their professional and athletic activities and should be regarded best tre

  14. Surgical Strategy for the Chronic Achilles Tendon Rupture. (United States)

    Lin, Yangjing; Yang, Liu; Yin, Li; Duan, Xiaojun


    Background. Chronic Achilles tendon rupture is usually misdiagnosed and treated improperly. This study aims to better understand the treatment of chronic Achilles tendon rupture. Methods. Patients who were not able to perform a single-limb heel rise were chosen. Pre- and postoperative magnetic resonance imaging (MRI) were conducted. By evaluating the presence or absence of Achilles tendon stumps and the gap length of rupture, V-Y advancement, gastrocnemius fascial turndown flap, or flexor halluces longus tendon transfer were selected for tendon repair. The function of ankle and foot was assessed by American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores and Achilles Tendon Total Rupture Score (ATRS). Results. Twenty-nine patients were followed up. One patient had superficial incision infection, which was healed after debridement and oral antibiotics. Three months postoperatively, MRI showed some signs of inflammation, which disappeared at one or two years postoperatively. All patients were able to perform a single-limb heel rise. Mean AOFAS scores and ATRS scores were increased at the latest follow-up. Conclusion. Surgical options can be determined by evaluating the presence of the Achilles tendon stumps and the gap length, which can avoid using the nearby tendon and yield satisfactory functional results.

  15. New finding in the radiographic diagnosis of Achilles tendon rupture

    Energy Technology Data Exchange (ETDEWEB)

    Newmark, H.; Mellon, W.S. Jr.; Malhotra, A.K.; Olken, S.M.; Halls, J.


    The authors describe a new radiographic sign of rupture of the Achilles tendon system. It is a fracture, with separation through an osteophyte at the insertion of this tendon. Previously reported signs are also discussed as well as the present case report.

  16. Surgical Strategy for the Chronic Achilles Tendon Rupture

    Directory of Open Access Journals (Sweden)

    Yangjing Lin


    Full Text Available Background. Chronic Achilles tendon rupture is usually misdiagnosed and treated improperly. This study aims to better understand the treatment of chronic Achilles tendon rupture. Methods. Patients who were not able to perform a single-limb heel rise were chosen. Pre- and postoperative magnetic resonance imaging (MRI were conducted. By evaluating the presence or absence of Achilles tendon stumps and the gap length of rupture, V-Y advancement, gastrocnemius fascial turndown flap, or flexor halluces longus tendon transfer were selected for tendon repair. The function of ankle and foot was assessed by American Orthopaedic Foot & Ankle Society (AOFAS ankle-hindfoot scores and Achilles Tendon Total Rupture Score (ATRS. Results. Twenty-nine patients were followed up. One patient had superficial incision infection, which was healed after debridement and oral antibiotics. Three months postoperatively, MRI showed some signs of inflammation, which disappeared at one or two years postoperatively. All patients were able to perform a single-limb heel rise. Mean AOFAS scores and ATRS scores were increased at the latest follow-up. Conclusion. Surgical options can be determined by evaluating the presence of the Achilles tendon stumps and the gap length, which can avoid using the nearby tendon and yield satisfactory functional results.

  17. [Surgical treatment for chronic achilles tendon rupture and severe scarring]. (United States)

    Sun, Chuan-Xiu; He, Sheng-Wei; Fang, Xu; Mi, Li-Dong; Du, Guang-Yu; Sun, Xue-Gang


    To evaluate the clinical efficacy of autologous semitendinosus and gracilis tendon grafting with anchor repair for the treatment of chronic achilles tendon rupture and severe scarring. From April 2010 to October 2012,26 patients with chronic achilles tendon rupture(with Myerson type III ) and severe scarring were treated with autologous semitendinosus and gracilis tendon grafting with anchor repair. There were 19 males and 7 females,with an average age of 32 years old (ranged, 22 to 47 years). The time from injury to surgery was from 3 to 12 months (7 months on average). The plantar flexion strength of all injuried feet attenuated and single heel rise test were positive in 26 cases before operation. Plaster immobilization and routine rehabilitation therapy were performed after operation. Clinical effects were evaluated by Arner-lindholm criterion and complications were observed after operation. All the patients were followed up from 12 to 24 months with a mean of 16 months. No complications such as achilles tendon re-rupture, wound infection, etc were found during follow-up period. According to the Arner-Lindholm standard, 15 cases got excellent results and 11 good. Using autologous semitendinosus and gracilis tendon grafts with anchor repair to treat chronic achilles tendon rupture and severe scarring is a perfect surgical procedure.

  18. Ultrasound evaluation of a spontaneous plantar fascia rupture. (United States)

    Louwers, Michael J; Sabb, Brian; Pangilinan, Percival H


    Plantar fascia rupture is an occasional complication in patients with chronic plantar fasciitis or in patients with plantar fasciitis treated with steroid injection. Very few cases of spontaneous plantar fascia rupture have been reported in the literature (Herrick and Herrick, Am J Sports Med 1983;11:95; Lun et al, Clin J Sports Med 1999;9:48-9; Rolf et al, J Foot Ankle Surg 1997;36:112-4; Saxena and Fullem, Am J Sports Med 2004;32:662-5). Spontaneous medial plantar fascia rupture in a 37-yr-old man with no preceding symptoms or steroid injections was confirmed with diagnostic ultrasound, which revealed severe fasciitis at the calcaneal insertion with partial tearing. After conservative treatment, the patient returned to full activities. We discuss the anatomy, risk factors, examination findings, and treatment for this condition, as well as the unique benefits that ultrasound offers over magnetic resonance imaging. It is important to consider plantar fascia rupture in patients with hindfoot pain and medioplantar ecchymosis, particularly if an injury occurred during acceleration maneuvers. Ultrasound in these cases can be used to diagnose a plantar fascia tear quickly, accurately, and cost-effectively.

  19. Spontaneous splenic rupture during the recovery phase of dengue fever. (United States)

    de Silva, W T T; Gunasekera, M


    Spontaneous splenic rupture is a rare but known complication of dengue fever. Previously reported cases have occurred early during the course of the disease and most cases have led to a fatal outcome. Here we report a case of spontaneous splenic rupture in a patient with dengue fever, which occurred during the recovery phase of the illness. A 28-year-old Sinhalese, Sri Lankan man presented with a history of fever, myalgia and vomiting of 4 days duration. Investigations revealed a diagnosis of dengue fever with no signs of plasma leakage. He was managed in the ward as per local protocol. During the recovery phase the patient developed severe abdominal distention with circulatory failure. Radiology revealed splenic rupture with massive amounts of abdominal free fluid. The patient was resuscitated and Emergency laparotomy with splenectomy was performed. The outcome was excellent with the patient making a complete recovery. Although splenic rupture is a known complication of dengue fever it may be manifested late in the disease process. A high degree of suspicion should be maintained and patients must be monitored even during the recovery phase of dengue fever. Early diagnosis and intervention can prevent mortality.

  20. [Plurifragmentary ruptures of the kidney. Wrapping by absorbable mesh]. (United States)

    Spay, G


    In two patients presenting with rupture of the kidney, the fragments of that organ were kept together by wrapping in a resorbable mesh after haemostasis and trimming. The post-operative period was uneventful. This method facilitates conservative renal surgery, even in cases with severe damage.