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1

Prediction of creep-rupture life of unidirectional titanium matrix composites subjected to transverse loading  

NASA Astrophysics Data System (ADS)

Titanium matrix composites (TMCs) incorporating unidirectional fiber reinforcement are considered as enabling materials technology for advanced engines which require high specific strength and elevated temperature capability. The resistance of unidirectional TMCs to deformation under longitudinally applied sustained loading at elevated temperatures has been well documented. Many investigators have shown that the primary weakness of the unidirectional TMC is its susceptibility to failure under very low transverse loads, especially under sustained loading. Hence, a reliable model is required to predict the creep-rupture life of TMCs subjected to different transverse stress levels over a wide range of temperatures. In this article, we propose a model to predict the creep-rupture life of unidirectional TMC subjected to transverse loading based on the creep-rupture life of unidirectional TMC subjected to transverse loading based on the creep-rupture behavior of the corresponding fiberless matrix. The model assumes that during transverse loading, the effective load-carrying matrix ligament along a row of fibers controls the creep-rupture strength and the fibers do not contribute to the creep resistance of the composite. The proposed model was verified using data obtained from different TMC fabricated using three matrix compositions, which exhibited distinctly different types of creep behavior. The results show that the creep-rupture life of the transverse TMC decreases linearly with increasing ratio of the fiber diameter to the ply thickness. The creeprupture life is also predicted to be independent of fiber spacing along the length of the specimen.

John, Reji; Khobaib, M.; Smith, Paul R.

1996-10-01

2

The variation in strength of transverse shocks in detonation waves  

Microsoft Academic Search

The variation of strength along a transverse shock associated with a Mach stem interaction at the detonation front in 2CO + O2 at 50 torr was measured by analysis of interferograms. An approximate solution to the flow behind the nonsteady reactive wave is obtained on the assumption of a power-law form for the density profile which is a reasonable representation

D. H. Edwards; A. T. Jones

1978-01-01

3

Rupture failure and mechanical strength of the electrode wire used in wire EDM  

Microsoft Academic Search

In the application of wire EDM, wire rupture is very troublesome and impedes further increase of cutting speed. Instead of the spark characteristics or the temperature distribution, the rupture mechanism and the mechanical strength of the wire are the focus of this investigation. Wire rupture is a mechanical failure in essence, although the process heat has significant influence on the

Y. F. Luo

1999-01-01

4

Stress-rupture strength and microstructural stability of W-HF-C wire reinforced superalloy composites  

NASA Technical Reports Server (NTRS)

W-Hf-C/superalloy composites were found to be potentially useful for turbine blade applications on the basis of stress-rupture strength. The 100-and 1000-hour rupture strengths obtained for 70 volume percent fiber composites tested at 1090 C were 420 and 280 MN/sq m (61,000 and 41,000 psi). The investigation indicated that with better quality fibers, composites having 100- and 1000-hour rupture strengths of 570 and 370 MN/sq m (82,000 and 54,000 psi) may be obtained. Metallographic studies indicated sufficient fiber-matrix compatibility for long time applications at 1090 C for 1000 hours or more.

Petrasek, D. W.; Signorelli, R. A.

1974-01-01

5

Transverse Strength of SCS-6 Silicon Carbide Fibers  

NASA Technical Reports Server (NTRS)

A diametral compression test used to measure the transverse strength of SCS-6 fibers before and after heat treatment. Subjecting fibers to diametral compression successfully produced transverse tensile failure in the form of fiber cracking along the same diametral plane in which the compressive load was applied. An analysis of the hoop stress along the diametral plane, in which the effect of the C core were included, showed that there is a large tensile hoop stress concentration in the SiC sheath at the interface between the C core and the SiC sheath, where the stress is 6.3 times greater than the stress present in a solid SiC fiber under identical loading. This high tensile hoop stress concentration promotes crack initiation near the core and significantly limits the capability of these fibers to withstand transverse compressive loading. The maximum tensile hoop stresses, located at the interface between the C core and SiC sheath, at the measured failure loads were 850 MPa for the as-received SCS-6 fiber and 1210 MPa for fibers exposed to a 1-h heat treatment at 1850 C in 138 Mpa of Ar.

Eldridge, Jeffrey I.; Wiening, Jonathan P.; Davison, Terry S.; Pindera, Marek-Jerzy

1993-01-01

6

Suppression of creep cavitation in precipitation-hardened austenitic stainless steel to enhance creep rupture strength  

Microsoft Academic Search

Extensive creep cavitation in Ti, Nb and Cu containing precipitation hardened austenitic steels was found to limit the usefulness\\u000a of deformation resistance to increase long-term creep rupture strength. The steels were microalloyed with boron and cerium\\u000a that resulted in increase in creep rupture strength and ductility of the steels significantly. Grain boundary sliding and\\u000a creep cavity nucleation and growth in

K. Laha; J. Kyono; N. Shinya

2010-01-01

7

Scaling effects on damage development, strength, and stress-rupture life laminated composites in tension  

NASA Astrophysics Data System (ADS)

The damage development and strength of ply-level scaled carbon/epoxy composite laminates having stacking sequence of ({+}thetasb{n}/{-}thetasb{n}/90sb{2n} rbracksb{s} where constraint ply angle, theta, was 0sp°, 15sp°, 30sp°,\\ 45sp°,\\ 60sp°, and 75sp°, and size was scaled as n = 1, 2, 3, and 4, is reported in Part I. X-radiography was used to monitor damage developments. First-ply failure stress, and tensile strength were recorded. First-ply failure of the midplane 90sp° plies depended on the stiffness of constraint plies, and size. All 24 cases were predicted using Zhang's shear-lag model and data generated from lbrack0sb2/90sb2rbracksb{s} cross-ply tests. Laminate strength was controlled by the initiation of a triangular-shaped local delamination of the surface angle plies. This delamination was predicted using O'Brien's strain energy release rate model for delamination of surface angle plies. For each ply angle, the smallest laminate was used to predict delamination (and strength) of the other sizes. The in-situ tensile strength of the 0sp° plies within different cross-ply, and quasi-isotropic laminates of varying size and stacking sequence is reported in Part II. No size effect was observed in the strength of 0sp° plies for those lay-ups having failure confined to the gauge section. Laminates exhibiting a size-strength relationship, had grip region failures for the larger sizes. A statistically significant set of 3-point bend tests of unidirectional beams were used to provide parameters for a Weibull model, to re-examine relationship between ultimate strength of 0sp° plies and specimen volume. The maximum stress in the 0sp° plies in bending, and the tensile strength of the 0sp° plies (from valid tests only) was the same. Weibull theory predicted loss of strength which was not observed in the experiments. An effort to model the durability and life of quasi-isotropic E-glass/913 epoxy composite laminates under steady load and in an acidic environment is reported in Part III. Stress-rupture tests of unidirectional coupons immersed in a weak hydrochloric acid solution was conducted to determine their stress-life response. Creep tests were conducted on unidirectional coupons parallel and transverse to the fibers, and on {±}45sp° layups to characterize the lamina stress- and time-dependent compliances. These data were used in a composite stress-rupture life model, based on the critical element modeling philosophy of Reifsnider, to predict the life of two ply-level thickness-scaled quasi-isotropic laminates.

Lavoie, J. Andre

8

Prediction of residual tensile strength of transversely impacted composite laminates  

NASA Technical Reports Server (NTRS)

The response to low velocity impact of graphite-epoxy T300/5208 composite laminates is discussed. Steel balls of 3/8 inch, 5/8 inch, and 1 inch diameter were the projectiles. Impact energy was limited to 1.2 joules. Impacted specimens were ultrasonically C scanned to determine the impact damaged region. The threshold value of impact energy for impact damage was found to be approximately 0.3 joules. A model was developed to predict the tensile residual strength of impact damaged specimens from fracture mechanics concepts. Impacted specimens were tested in tension to provide a fracture data base. The experimental results agreed well with the predictions from fracture mechanics. In this study, the maximum impact velocity used to simulate the low velocity transverse impact from common objects like tool drops was 10 m/s.

Lal, K. M.

1982-01-01

9

Influence of Specimen Preparation and Specimen Size on Composite Transverse Tensile Strength and Scatter  

NASA Technical Reports Server (NTRS)

The influence of specimen polishing, configuration, and size on the transverse tension strength of two glass-epoxy materials, and one carbon-epoxy material, loaded in three and four point bending was evaluated. Polishing machined edges, arid/or tension side failure surfaces, was detrimental to specimen strength characterization instead of yielding a higher, more accurate, strength as a result of removing inherent manufacture and handling flaws. Transverse tension strength was typically lower for longer span lengths due to the classical weakest link effect. However, strength was less sensitive to volume changes achieved by increasing specimen width. The Weibull scaling law typically over-predicted changes in transverse tension strengths in three point bend tests and under-predicted changes in transverse tension strengths in four point bend tests. Furthermore, the Weibull slope varied with specimen configuration, volume, and sample size. Hence, this scaling law was not adequate for predicting transverse tension strength of heterogeneous, fiber-reinforced, polymer matrix composites.

OBrien, T. Kevin; Chawan, Arun D.; DeMarco, Kevin; Paris, Isabelle

2001-01-01

10

Self-healing slip pulses in dynamic rupture models due to velocity-dependent strength  

USGS Publications Warehouse

Seismological observations of short slip duration on faults (short rise time on seismograms) during earthquakes are not consistent with conventional crack models of dynamic rupture and fault slip. In these models, the leading edge of rupture stops only when a strong region is encountered, and slip at an interior point ceases only when waves from the stopped edge of slip propagate back to that point. In contrast, some seismological evidence suggests that the duration of slip is too short for waves to propagate from the nearest edge of the ruptured surface, perhaps even if the distance used is an asperity size instead of the entire rupture dimension. What controls slip duration, if not dimensions of the fault or of asperities? In this study, dynamic earthquake rupture and slip are represented by a propagating shear crack. For all propagating shear cracks, slip velocity is highest near the rupture front, and at a small distance behind the rupture front, the slip velocity decreases. As pointed out by Heaton (1990), if the crack obeys a negative slip-rate-dependent strength relation, the lower slip velocity behind the rupture front will lead to strengthening that further reduces the velocity, and under certain circumstances, healing of slip can occur. The boundary element method of Hamano (1974) is used in a program adapted from Andrews (1985) for numerical simulations of mode II rupture with two different velocity-dependent strength functions. For the first function, after a slip-weakening displacement, the crack follows an exponential velocity-weakening relation. The characteristic velocity V0 of the exponential determines the magnitude of the velocity-dependence at dynamic velocities. The velocity-dependence at high velocity is essentially zero when V0 is small and the resulting slip velocity distribution is similar to slip weakening. If V0 is larger, rupture propagation initially resembles slip-weakening, but spontaneous healing occurs behind the rupture front. The rise time and rupture propagation velocity depend on the choice of constitutive parameters. The second strength function is a natural log velocity-dependent form similar to constitutive laws that fit experimental rock friction data at lower velocities. Slip pulses also arise with this function. For a reasonable choice of constitutive parameters, slip pulses with this function do not propagate at speeds greater than the Raleighwave velocity. The calculated slip pulses are similar in many aspects to seismic observations of short rise time. In all cases of self-healing slip pulses, the residual stress increases with distance behind the trailing edge of the pulse so that the final stress drop is much less than the dynamic stress drop, in agreement with the model of Brune (1976) and some recent seismological observations of rupture.

Beeler, N. M.; Tullis, T. E.

1996-01-01

11

Creep rupture strength of activated-TIG welded 316L(N) stainless steel  

NASA Astrophysics Data System (ADS)

316L(N) stainless steel plates were joined using activated-tungsten inert gas (A-TIG) welding and conventional TIG welding process. Creep rupture behavior of 316L(N) base metal, and weld joints made by A-TIG and conventional TIG welding process were investigated at 923 K over a stress range of 160-280 MPa. Creep test results showed that the enhancement in creep rupture strength of weld joint fabricated by A-TIG welding process over conventional TIG welding process. Both the weld joints fractured in the weld metal. Microstructural observation showed lower ?-ferrite content, alignment of columnar grain with ?-ferrite along applied stress direction and less strength disparity between columnar and equiaxed grains of weld metal in A-TIG joint than in MP-TIG joint. These had been attributed to initiate less creep cavitation in weld metal of A-TIG joint leading to improvement in creep rupture strength.

Sakthivel, T.; Vasudevan, M.; Laha, K.; Parameswaran, P.; Chandravathi, K. S.; Mathew, M. D.; Bhaduri, A. K.

2011-06-01

12

Stress-rupture strength and microstructural stability of tungsten-hafnium-carbon-wire reinforced superalloy composites  

NASA Technical Reports Server (NTRS)

Tungsten-hafnium-carbon - superalloy composites were found to be potentially useful for turbine blade applications on the basis of stress-rupture strength. The 100- and 1000-hr rupture strengths calculated for 70 vol. % fiber composites based on test data at 1090C (2000F) were 420 and 280 MN/m2 (61,000 and 41,000 psi, respectively). The investigation indicated that, with better quality fibers, composites having 100- and 1000-hr rupture strengths of 570 and 370 MN/m2 (82,000 and 54,000 psi, respectively), may be obtained. Metallographic studies indicated sufficient fiber-matrix compatibility for 1000 hr or more at 1090C (2000F).

Petrasek, D. W.; Signorelli, R. A.

1974-01-01

13

Comparison of the Tensile, Creep, and Rupture Strength Properties of Stoichiometric SiC Fibers  

NASA Technical Reports Server (NTRS)

Tensile strength, creep strength, and rupture strength properties were measured for the following types of polymer-derived stoichiometric SiC fibers: Hi-Nicalon Type S from Nippon Carbon, Tyranno SA from Ube, and Sylramic from Dow Corning. Also included in this study were an earlier version of the SA fiber plus two recent developmental versions of the Sylramic fiber. The tensile strength measurements were made at room temperature on as-received fibers and on fibers after high-temperature inert exposure. The creep-rupture property data were obtained at 1400 deg C in air as well as, argon. Some fiber types showed strong effects of environment on their strength properties. These results are compared and discussed in terms of underlying mechanisms and implications for ceramic composites.

Yun, H. M.; DiCarlo, J. A.

1999-01-01

14

Composite Stress Rupture: A New Reliability Model Based on Strength Decay  

NASA Technical Reports Server (NTRS)

A model is proposed to estimate reliability for stress rupture of composite overwrap pressure vessels (COPVs) and similar composite structures. This new reliability model is generated by assuming a strength degradation (or decay) over time. The model suggests that most of the strength decay occurs late in life. The strength decay model will be shown to predict a response similar to that predicted by a traditional reliability model for stress rupture based on tests at a single stress level. In addition, the model predicts that even though there is strength decay due to proof loading, a significant overall increase in reliability is gained by eliminating any weak vessels, which would fail early. The model predicts that there should be significant periods of safe life following proof loading, because time is required for the strength to decay from the proof stress level to the subsequent loading level. Suggestions for testing the strength decay reliability model have been made. If the strength decay reliability model predictions are shown through testing to be accurate, COPVs may be designed to carry a higher level of stress than is currently allowed, which will enable the production of lighter structures

Reeder, James R.

2012-01-01

15

Copper, Boron, and Cerium Additions in Type 347 Austenitic Steel to Improve Creep Rupture Strength  

NASA Astrophysics Data System (ADS)

Type 347 austenitic stainless steel (18Cr-12Ni-Nb) was alloyed with copper (3 wt pct), boron (0.01 to 0.06 wt pct), and cerium (0.01 wt pct) with an aim to increase the creep rupture strength of the steel through the improved deformation and cavitation resistance. Short-term creep rupture strength was found to increase with the addition of copper in the 347 steel, but the long-term strength was inferior. Extensive creep cavitation deprived the steel of the beneficial effect of creep deformation resistance induced by nano-size copper particles. Boron and cerium additions in the copper-containing steel increased its creep rupture strength and ductility, which were more for higher boron content. Creep deformation, grain boundary sliding, and creep cavity nucleation and growth in the steel were found to be suppressed by microalloying the copper-containing steel with boron and cerium, and the suppression was more for higher boron content. An auger electron spectroscopic study revealed the segregation of boron instead of sulfur on the cavity surface of the boron- and cerium-microalloyed steel. Cerium acted as a scavenger for soluble sulfur in the steels through the precipitation of cerium sulfide (CeS). This inhibited the segregation of sulfur and facilitated the segregation of boron on cavity surface. Boron segregation on the nucleated cavity surface reduced its growth rate. Microalloying the copper-containing 347 steel with boron and cerium thus enabled to use the full extent of creep deformation resistance rendered by copper nano-size particle by increase in creep rupture strength and ductility.

Laha, Kinkar; Kyono, J.; Shinya, Norio

2012-04-01

16

Shear Strength Models of Exterior Beam-Column Joints without Transverse Reinforcement.  

National Technical Information Service (NTIS)

This study suggests a semi-empirical model and an analytical model to predict the shear strength of reinforced concrete (RC) exterior beam-column joints without transverse reinforcement (denoted as unreinforced) in the joint region. A large experimental d...

K. M. Mosalam S. Park

2009-01-01

17

The Influence of Constitution and Microstructure on the Transverse Strength of a Crystallized Glass.  

National Technical Information Service (NTIS)

The thermal expansion behavior and abraded and unabraded transverse strengths of a glass, nucleated glass, and 15%, 30% and 50% crystalline glass-ceramic were correlated with the constitution and microstructure of these specimens. X-ray diffraction patter...

R. F. Davis

1966-01-01

18

Sensitivity of a disc rupture strength test to air bubble pores in phosphate-bonded investment materials at elevated temperatures  

Microsoft Academic Search

Objectives: To investigate the sensitivity of a modified disc rupture test to variables affecting the strength of four phosphate-bonded investment materials under conditions closely resembling the in-service environment. This study examined the influence of air bubble pores on the strength of phosphate bonded investment materials at a temperature of 900°C.Method: A modified disc rupture configuration was used to test a

Andrzej S Juszczyk; David R Radford; Richard V Curtis

2002-01-01

19

Influence of Specimen Preparation and Specimen Size on the Transverse Tensile Strength and Scatter of Glass Epoxy Laminates  

NASA Technical Reports Server (NTRS)

The influence of specimen polishing, specimen configuration, and specimen size on the transverse tension strength of two glass epoxy materials loaded in three and four point bending was evaluated. Polishing machined edges, and/or tension side failure surfaces, was detrimental to specimen strength characterization instead of yielding a higher, more accurate, strength as a result of removing inherent manufacture and handling flaws. Transverse tension strength was sensitive to span length due to the classical weakest link effect. However, strength was less sensitive to volume changes achieved by increasing specimen width. The Weibull scaling law over-predicted changes in transverse tension strengths in three point bend tests and under-predicted changes in transverse tension strengths in four point bend tests. Furthermore, the Weibull slope varied with specimen configuration, volume, and sample size. Hence, the utility of this scaling law for predicting transverse tension strength is unclear.

OBrien, T. Kevin; Chawan, Arun D.; DeMarco, Kevin

1999-01-01

20

Scale effects on the transverse tensile strength of graphite epoxy composites  

NASA Technical Reports Server (NTRS)

The influence of material volume on the transverse tensile strength of AS4/3501-6 graphite epoxy composites was investigated. Tensile tests of 90 degree laminates with 3 different widths and 5 different thicknesses were conducted. A finite element analysis was performed to determine the influence of the grip on the stress distribution in the coupons and explain the tendency for the distribution of failure locations to be skewed toward the grip. Specimens were instrumented with strain gages and extensometers to insure good alignment and to measure failure strains. Data indicated that matrix dominated strength properties varied with the volume of material that was stressed, with the strength decreasing as volume increased. Transverse strength data were used in a volumetric scaling law based on Weibull statistics to predict the strength of 90 degree laminates loaded in three point bending. Comparisons were also made between transverse strength measurements and out-of-plane interlaminar tensile strength measurements from curved beam bending tests. The significance of observed scale effects on the use of tests for material screening, quality assurance, and design allowables is discussed.

Obrien, T. Kevin; Salpekar, Satish A.

1992-01-01

21

The Effects of Clustered Porosity on the Shear Strength of A 514F Transverse Fillet Welds.  

National Technical Information Service (NTIS)

This report presents the results of a study of the effects of clustered porosity on the transverse shear strength of A 514F steel weldments. The amount of porosity induced into the specimens ranged from zero to over 20 percent of the fracture surfaces. Re...

H. S. Lamba E. P. Cox

1976-01-01

22

Transverse creep and stress-rupture of borsic-aluminum composites and borsic-aluminum composites containing stainless steel and titanium  

Microsoft Academic Search

The transverse creep and stress rupture behavior of a number of Borsic?-aluminum composites was investigated at temperatures\\u000a from 200? to 400?C. The cpmposites studied consisted of nominally 50 vol pct Borsic fiber and included matrices of 6061, 2024,\\u000a 2219, and 5052 aluminum alloys. The effect of heat treatment was studied in the heat-treatable alloys. Where transverse composite\\u000a behavior differed from

E. M. Breinan; K. G. Kreider

1973-01-01

23

Transverse creep and stress-rupture of borsic-aluminum composites and borsic-aluminum composites containing stainless steel and titanium  

Microsoft Academic Search

The transverse creep and stress rupture behavior of a number of Borsic®-aluminum composites was investigated at temperatures from 200° to 400°C. The cpmposites studied consisted of nominally 50 vol pct Borsic fiber and included matrices of 6061, 2024, 2219, and 5052 aluminum alloys. The effect of heat treatment was studied in the heat-treatable alloys. Where transverse composite behavior differed from

E. M. Breinan; K. G. Kreider

1973-01-01

24

Development of high strength nickel-base cast superalloy with superior creep rupture life  

SciTech Connect

Elevating the operating temperature is considered to be the most effective for increasing the thermal efficiency of power generators or chemical plants. For this reason, the development of materials exhibiting superior creep strength and corrosion resistance is required. Directionally solidification (DS) and single crystal (SC) superalloys have been developed for advanced commercial and military applications. Owing to the difficulties to produce DS and SC alloys and the high casting cost, it is necessary to develop conventional casting superalloys with excellent properties similar to those of DS and SC alloys. For this purpose, a program to design and develop cast nickel-base superalloys was initiated in this investigation. Some methods, so called PHACOMP-Nv or NEW-PHACOMP-Md, allow one to estimate the phase stability of alloys, and eventually to improve it by modification of the composition. In fact these methods do not have a strong physical basis but are rather based on empirical correlations. In this paper, six compositions were calculated according to the conventional PHACOMP parameter calculation and based on the inventions Ni-Cr-W-Al-Ti-Ta system. Among them an alloy with high strength and superior creep rupture properties was determined. The phase stability was discussed using NEW-PHACOMP-Md concept.

Yao, X. [Shanghai Jiao Tong Univ. (China). Dept. of Materials Science] [Shanghai Jiao Tong Univ. (China). Dept. of Materials Science; Kim, H.; Choi, J. [Korea Inst. of Science and Technology, Cheongryang, Seoul (Korea, Republic of). Div. of Metals] [Korea Inst. of Science and Technology, Cheongryang, Seoul (Korea, Republic of). Div. of Metals

1996-10-15

25

Analysis of Ninety Degree Flexure Tests for Characterization of Composite Transverse Tensile Strength  

NASA Technical Reports Server (NTRS)

Finite element (FE) analysis was performed on 3-point and 4-point bending test configurations of ninety degree oriented glass-epoxy and graphite-epoxy composite beams to identify deviations from beam theory predictions. Both linear and geometric non-linear analyses were performed using the ABAQUS finite element code. The 3-point and 4-point bending specimens were first modeled with two-dimensional elements. Three-dimensional finite element models were then performed for selected 4-point bending configurations to study the stress distribution across the width of the specimens and compare the results to the stresses computed from two-dimensional plane strain and plane stress analyses and the stresses from beam theory. Stresses for all configurations were analyzed at load levels corresponding to the measured transverse tensile strength of the material.

OBrien, T. Kevin; Krueger, Ronald

2001-01-01

26

Surface ruptures on the transverse Xiaoyudong fault: A significant segment boundary breached during the 2008 Wenchuan earthquake, China  

NASA Astrophysics Data System (ADS)

The ~ 220 km-long rupture of the 2008 Mw 7.9 Wenchuan earthquake breached several km-scale geometric discontinuities along strike, including the previously un-mapped NW-trending Xiaoyudong fault, connecting between the two major, NE-trending rupture planes on the Beichuan and Pengguan Faults. In this paper, we present high-resolution mapping of the 8-km-long surface breaks and sinistral oblique thrusting coseismic slip on the Xiaoyudong fault. Scarp height is the largest at the NW end, reaching 3.5 m, and decreases southward in steps to less than 0.2 m, with an average slip gradient of 6 × 10- 3 at a few tens of meters length scale, but up to 50 × 10- 3 locally. Left-lateral offsets co-vary with the vertical component. The largest sinistral slip vector we observed is 2.2 m. Geological and geophysical evidence suggests that the Xiaoyudong fault is likely a ~ 30°SW-dipping lateral ramp that soles into the Pengguan fault, and at its northwestern end intersects with the Beichuan fault, where the latter has a step in the fault plane. Kinematically, the Xiaoyudong fault functions as a tear and conjugate fault and coincides with significant coseismic slip rake rotations on both the Beichuan and Pengguan Faults. Similar correlation of fault bends with sharp changes in faulting style occurs at other steps along the Wenchuan rupture. The Xiaoyudong fault may have played a positive role in linking coseismic slip partitioning between parallel reverse fault planes, facilitating the growth of a longer and more destructive rupture. This highlights the role of tear faults in bridging ruptures between segments, such that reverse-type ruptures can breach steps wider than anticipated from strike-slip fault examples. Transfer faults are common, and perhaps poorly documented features in reverse fault systems and their roles in ruptures may increase the maximum potential earthquake magnitude for fold-and-thrust belts.

Liu-Zeng, Jing; Sun, Jing; Wang, Peng; Hudnut, Kenneth W.; Ji, Chen; Zhang, Zhihui; Xu, Qiang; Wen, Li

2012-12-01

27

Effects on stress rupture life and tensile strength of tin additions to Inconel 718  

NASA Technical Reports Server (NTRS)

Because Inconel 718 represents a major use of columbium and a large potential source of columbium for aerospace alloys could be that of columbium derived from tin slags, the effects of tin additions to Inconel 718 at levels which might be typical of or exceed those anticipated if tin slag derived columbium were used as a melting stock were investigated. Tin was added to 15 pound Inconel 718 heats at levels varying from none added to approximately 10,000 ppm (1 wt%). Limited 1200 F stress rupture testing was performed at stresses from 68,000 to 115,000 psi and a few tensile tests were performed at room temperature, 800 and 1200 F. Additions of tin in excess of 800 ppm were detrimental to ductility and stress rupture life.

Dreshfield, R. L.; Johnson, W.

1982-01-01

28

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

NASA Astrophysics Data System (ADS)

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 are quite similar with both methods. However, ruptures in DYNA3D propagate more rapidly through the barriers and generate less high-frequency variations of slip than ruptures in RSQSim. The qualitative agreement of these two very different methods is good and may improve with further tuning of quasi-dynamic computational parameters. Using the same heterogeneous strength distribution as in the single-event examples, we use RSQSim to simulate several thousand years of additional seismicity. The effects of the asperities along the fault become much more subtle over multiple earthquake cycles as the shear stress adjusts to the higher normal stress in the asperities. Subsequent large spontaneous events rupture at much more variable and significantly slower velocities through the evolved stress states than through the uniform initial shear stress state of the first, artificially nucleated event. Indeed, the ruptures occasionally nearly come to a halt before continuing. These complex ruptures will produce very different ground motions than the more coherent ruptures seen in ruptures through smoother initial stress states.

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

2008-12-01

29

Creep and Rupture Strength of an Advanced CVD SiC Fiber.  

National Technical Information Service (NTIS)

In the as-produced condition, the room temperature strength (approx. 6 GPa) of Textron Specialty Materials' 50 microns CVD SiC fiber represents the highest value thus far obtained for commercially produced polycrystalline SiC fibers. To understand whether...

J. C. Goldsby H. M. Yun J. A. DiCarlo

1997-01-01

30

Improvement of the Transverse Strength of Continuous Filament Reinforced Light Alloys.  

National Technical Information Service (NTIS)

This research was directed toward improvement in the transverse properties of light alloys reinforced with Borsic fibers. Encapsulation of approximately 10% of silicon carbide whiskers, aligned normal to the Borsic fibers in 6061 alloys, resulted in a 30%...

F. E. Swindells P. J. Lare

1975-01-01

31

Influence of internal oxidation on the stress-rupture strength of a vanadium-titanium alloy  

SciTech Connect

The alloying of vanadium with substitutional elements of group IVa (Ti, Zr, Hf) significantly increases its high-temperature strength. However, in long service in gaseous media containing oxygen as an impurity, its mechanical properties become poorer as the result of the increase in oxidation rate, the interaction of oxygen with the alloying element, escape of it from the composition of the solid solution, segregation of the oxygen and the reaction products at the grain boundaries, etc. It is possible to eliminate these if in advance a structure with thermodynamically stable oxide particles of the necessary morphology and dispersion is formed by internal oxidation. The purpose of this work was a study of the influence of internal oxidation on the structure and stressrupture strength of vanadium alloyed with titanium.

Maksimovich, G.G.; Eliseeva, O.I.; Kalyandruk, V.I.; Lyutyi, E.M.; Shirokov, V.V.

1985-05-01

32

Assessment of an improved multiaxial strength theory based on creep-rupture data for type 316 stainless steel  

SciTech Connect

A new multiaxial strength theory incorporating three independent stress parameters was developed and reported by the author in 1984. It was formally incorporated into ASME Code Case N47-29 in 1990. In the earlier paper, the new model was shown to provide significantly more accurate stress-rupture life predictions, than the classical theories of von Mises, Tresca, and Rankine, for the type 304 stainless steel tested at 593{degrees}C under different biaxial stress states. Further assessments for other alloys are showing similar results. The current paper provides additional results for type 316 stainless steel specimens tested at 600{degrees}C under tension-tension and tension-compression stress states and shows 2--3 orders of magnitude reduction in the scatter in predicted versus observed lives. A key feature of the new theory, which incorporates the maximum deviatoric stress, the first invariant of the stress tensor, and the second invariant of the deviatoric stress tensor, is its ability to distinguish between life under tensile versus compressive stress states.

Huddleston, R.L.

1992-01-01

33

Assessment of an improved multiaxial strength theory based on creep-rupture data for type 316 stainless steel  

SciTech Connect

A new multiaxial strength theory incorporating three independent stress parameters was developed and reported by the author in 1984. It was formally incorporated into ASME Code Case N47-29 in 1990. In the earlier paper, the new model was shown to provide significantly more accurate stress-rupture life predictions than the classical theories of von Mises, Tresca, and Rankine, for type 304 stainless steel tested at 593 C under different biaxial stress states. Further assessments for other alloys are showing similar results. The current paper provides additional results for type 316 stainless steel specimens tested at 600 C under tension-tension and tension-compression stress states and shows 2-3 orders of magnitude reduction in the scatter in predicted versus observed lives. A key feature of the new theory, which incorporates the maximum deviatoric stress, the first invariant of the stress tensor, and the second invariant of the deviatoric stress tensor, is its ability to distinguish between life under tensile versus compressive stress states.

Huddleston, R.L. (Oak Ridge National Lab., TN (United States))

1993-05-01

34

The Strength and Stiffness in Transverse Tension of Unidirectional Carbon Fibre Reinforced Plastic.  

National Technical Information Service (NTIS)

The development of test specimens for the determination of the tensile strength, strain to failure, and Young's modulus of unidirectional carbon fiber reinforced plastics in a direction perpendicular to the fibers is described. Also presented are the resu...

D. L. Mead

1972-01-01

35

Strength and rupture-life transitions caused by secondary carbide precipitation in HT-9 during high-temperature low-rate mechanical testing  

SciTech Connect

The martensitic-ferritic alloy HT-9 is slated for long-term use as a fuel-cladding material in the Integral Fast Reactor. Analysis of published high-temperature mechanical property data suggests that secondary carbide precipitation would occur during service life causing substantial strengthening of the as-heat-treated material. Aspects of the kinetics of this precipitation process are extracted from calculations of the back stress necessary to produce the observed strengthening effect under various creep loading conditions. The resulting Arrhenius factor is shown to agree quantitatively with shifts to higher strength of crept material in reference to the intrinsic strength of HT-9. The results of very low constant strain-rate high-temperature tensile tests on as-heat-treated HT-9 that focus on the transition in strength with precipitation will be presented and related to rupture-life.

DiMelfi, R.J.; Gruber, E.E.; Kramer, J.M.; Hughes, T.H.

1992-11-01

36

Biaxial normal strength behavior in the axial-transverse plane for human trabecular bone--effects of bone volume fraction, microarchitecture, and anisotropy.  

PubMed

The biaxial failure behavior of the human trabecular bone, which has potential relevance both for fall and gait loading conditions, is not well understood, particularly for low-density bone, which can display considerable mechanical anisotropy. Addressing this issue, we investigated the biaxial normal strength behavior and the underlying failure mechanisms for human trabecular bone displaying a wide range of bone volume fraction (0.06-0.34) and elastic anisotropy. Micro-computed tomography (CT)-based nonlinear finite element analysis was used to simulate biaxial failure in 15 specimens (5 mm cubes), spanning the complete biaxial normal stress failure space in the axial-transverse plane. The specimens, treated as approximately transversely isotropic, were loaded in the principal material orientation. We found that the biaxial stress yield surface was well characterized by the superposition of two ellipses--one each for yield failure in the longitudinal and transverse loading directions--and the size, shape, and orientation of which depended on bone volume fraction and elastic anisotropy. However, when normalized by the uniaxial tensile and compressive strengths in the longitudinal and transverse directions, all of which depended on bone volume fraction, microarchitecture, and mechanical anisotropy, the resulting normalized biaxial strength behavior was well described by a single pair of (longitudinal and transverse) ellipses, with little interspecimen variation. Taken together, these results indicate that the role of bone volume fraction, microarchitecture, and mechanical anisotropy is mostly accounted for in determining the uniaxial strength behavior and the effect of these parameters on the axial-transverse biaxial normal strength behavior per se is minor. PMID:24121715

Sanyal, Arnav; Keaveny, Tony M

2013-12-01

37

A fluid-structure interaction-based numerical investigation on the evolution of stress, strength and rupture potential of an abdominal aortic aneurysm.  

PubMed

An abdominal aortic aneurysm (AAA) is an irreversible dilation of the abdominal artery. Once an aneurysm is detected by doctors, clinical intervention is usually recommended. The interventions involve traditional open surgery repair and endovascular aneurysm repair with a stent graft. Both types of prophylactic procedures are expensive and not without any risk to the patient. It is very difficult to balance the risk of aneurysm repair and the chance of rupture. The reason lies in that the changing trend of characteristic physical quantities with the evolution of AAA and the mechanisms that give rise to it are still not completely clear. In this study, computational 3D patient-specific model for investigating AAA development was established based on computed tomography (CT) images. Results showed that as the aneurysm evolved, peak wall stress and time-averaged wall shear stress distribution patterns changed. The expansion of AAA wall resulted in the increment of peak stress. The AAA wall compliance not only showed different magnitudes at different cross-sections of the aneurismal body, but also changed with the development of the aneurysm. Furthermore, minimum wall strength and rupture potential index during the three stages of AAA evolution were also investigated in detail. This study might provide valuable information on how to further explore the mechanical basis and the rupture potential during AAA evolution, and that it may assist clinical diagnostic procedures and avoid the potential risk of unnecessary surgical intervention. PMID:22289116

Wang, Xiaohong; Li, Xiaoyang

2013-01-01

38

A Comparison of Creep Rupture Strength of Ferritic/Austenitic Dissimilar Weld Joints of Different Grades of Cr-Mo Ferritic Steels  

NASA Astrophysics Data System (ADS)

Evaluations of creep rupture properties of dissimilar weld joints of 2.25Cr-1Mo, 9Cr-1Mo, and 9Cr-1MoVNb steels with Alloy 800 at 823 K were carried out. The joints were fabricated by a fusion welding process employing an INCONEL 182 weld electrode. All the joints displayed lower creep rupture strength than their respective ferritic steel base metals, and the strength reduction was greater in the 2.25Cr-1Mo steel joint and less in the 9Cr-1Mo steel joint. Failure location in the joints was found to shift from the ferritic steel base metal to the intercritical region of the heat-affected zone (HAZ) of the ferritic steel (type IV cracking) with the decrease in stress. At still lower stresses, the failure in the joints occurred at the ferritic/austenitic weld interface. The stress-life variation of the joints showed two-slope behavior and the slope change coincided with the occurrence of ferritic/austenitic weld interface cracking. Preferential creep cavitation in the soft intercritical HAZ induced type IV failure, whereas creep cavitation at the interfacial particles induced ferritic/austenitic weld interface cracking. Micromechanisms of the type IV failure and the ferritic/austenitic interface cracking in the dissimilar weld joint of the ferritic steels and relative cracking susceptibility of the joints are discussed based on microstructural investigation, mechanical testing, and finite element analysis (FEA) of the stress state across the joint.

Laha, K.; Chandravathi, K. S.; Parameswaran, P.; Goyal, Sunil; Mathew, M. D.

2012-04-01

39

The effect of joint surface contours and glass fiber reinforcement on the transverse strength of repaired acrylic resin: An in vitro study  

PubMed Central

Background: Denture fracture is an unresolved problem in complete denture prosthodontics. However, the repaired denture often experiences a refracture at the repaired site due to poor transverse strength. Hence, this study was conducted to evaluate the effect of joint surface contours and glass fiber reinforcement on the transverse strength of repaired acrylic resins. Materials and Methods: A total of 135 specimens of heat polymerized polymethyl methacrylate resin of dimensions 64 × 10 × 2.5 mm were fabricated. Fifteen intact specimens served as the control and 120 test specimens were divided into four groups (30 specimens each), depending upon the joint surface contour (butt, bevel, rabbet and round), with two subgroups based on type of the repair. Half of the specimens were repaired with plain repair resin and the other half with glass fibers reinforced repair resin. Transverse strength of the specimens was determined using three-point bending test. The results were analyzed using one-way ANOVA and Tukey post-hoc test (?= 0.05). Results: Transverse strength values for all repaired groups were significantly lower than those for the control group (P < 0.001) (88.77 MPa), with exception of round surface design repaired with glass fiber reinforced repair resin (89.92 MPa) which was significantly superior to the other joint surface contours (P < 0.001). Glass fiber reinforced resin significantly improved the repaired denture base resins as compared to the plain repair resin (P < 0.001). Conclusion: Specimens repaired with glass fiber reinforced resin and round surface design exhibited highest transverse strength; hence, it can be advocated for repair of denture base resins.

Anasane, Nayana; Ahirrao, Yogesh; Chitnis, Deepa; Meshram, Suresh

2013-01-01

40

Numerical analysis of stress distribution in Cu-stabilized GdBCO CC tapes during anvil tests for the evaluation of transverse delamination strength  

NASA Astrophysics Data System (ADS)

Rare-earth–Ba–Cu–O (REBCO) based coated conductors (CCs) are now being used for electric device applications. For coil-based applications such as motors, generators and magnets, the CC tape needs to have robust mechanical strength along both the longitudinal and transverse directions. The CC tape in these coils is subjected to transverse tensile stresses during cool-down and operation, which results in delamination within and between constituent layers. In this study, in order to explain the behaviour observed in the evaluation of c-axis delamination strength in Cu-stabilized GdBCO CC tapes by anvil tests, numerical analysis of the mechanical stress distribution within the CC tape has been performed. The upper anvil size was varied in the analysis to understand the effect of anvil size on stress distribution within the multilayered CC tape, which is closely related to the delamination strength, delamination mode and delamination sites that were experimentally observed. The numerical simulation results showed that, when an anvil size covering the whole tape width was used, the REBCO coating film was subjected to the largest stress, which could result in low mechanical delamination and electromechanical delamination strengths. Meanwhile, when smaller-sized anvils were used, the copper stabilizer layer would experience the largest stress among all the constituent layers of the CC tape, which could result in higher mechanical and electromechanical delamination strengths, as well as high scattering of both of these delamination strengths. As a whole, the numerical simulation results could explain the damage evolution observed in CC tapes tested under transverse tensile stress, as well as the transverse tensile stress response of the critical current, Ic.

Dizon, John Ryan C.; Gorospe, Alking B.; Shin, Hyung-Seop

2014-05-01

41

Ruptured eardrum  

MedlinePLUS

Tympanic membrane perforation; Eardrum - ruptured or perforated; Perforated eardrum ... Buttaravoli P, Leffler SM. Perforated tympanic membrane (ruptured eardrum). ... Pa: Mosby Elsevier; 2012:chap 37. Kerschner JE. Otitis ...

42

Centrally-Rupturing Squib-Closure Disks  

NASA Technical Reports Server (NTRS)

Rupture-disk design makes squib action more predictable. In new design, center of rupture disk contains cruciform indentation in which thickness reduced to about 0.5 mil (0.013 mm). Reduces strength of center of rupture disk in same manner as that of pull tabs on beverage cans; therefore, disk will fail predictably in center.

Richter, R.

1986-01-01

43

Describing Soils: Calibration Tool for Teaching Soil Rupture Resistance  

ERIC Educational Resources Information Center

Rupture resistance is a measure of the strength of a soil to withstand an applied stress or resist deformation. In soil survey, during routine soil descriptions, rupture resistance is described for each horizon or layer in the soil profile. The lower portion of the rupture resistance classes are assigned based on rupture between thumb and…

Seybold, C. A.; Harms, D. S.; Grossman, R. B.

2009-01-01

44

Monte Carlo characterization of skin doses in 6 MV transverse field MRI-linac systems: Effect of field size, surface orientation, magnetic field strength, and exit bolus  

SciTech Connect

Purpose: The main focus of this work is to continue investigations into the Monte Carlo predicted skin doses seen in MRI-guided radiotherapy. In particular, the authors aim to characterize the 70 {mu}m skin doses over a larger range of magnetic field strength and x-ray field size than in the current literature. The effect of surface orientation on both the entry and exit sides is also studied. Finally, the use of exit bolus is also investigated for minimizing the negative effects of the electron return effect (ERE) on the exit skin dose. Methods: High resolution GEANT4 Monte Carlo simulations of a water phantom exposed to a 6 MV x-ray beam (Varian 2100C) have been performed. Transverse magnetic fields of strengths between 0 and 3 T have been applied to a 30x30x20 cm{sup 3} phantom. This phantom is also altered to have variable entry and exit surfaces with respect to the beam central axis and they range from -75 deg. to +75 deg. The exit bolus simulated is a 1 cm thick (water equivalent) slab located on the beam exit side. Results: On the entry side, significant skin doses at the beam central axis are reported for large positive surface angles and strong magnetic fields. However, over the entry surface angle range of -30 deg. to -60 deg., the entry skin dose is comparable to or less than the zero magnetic field skin dose, regardless of magnetic field strength and field size. On the exit side, moderate to high central axis skin dose increases are expected except at large positive surface angles. For exit bolus of 1 cm thickness, the central axis exit skin dose becomes an almost consistent value regardless of magnetic field strength or exit surface angle. This is due to the almost complete absorption of the ERE electrons by the bolus. Conclusions: There is an ideal entry angle range of -30 deg. to -60 deg. where entry skin dose is comparable to or less than the zero magnetic field skin dose. Other than this, the entry skin dose increases are significant, especially at higher magnetic fields. On the exit side there is mostly moderate to high skin dose increases for 0.2-3 T with the only exception being large positive angles. Exit bolus of 1 cm thickness will have a significant impact on lowering such exit skin dose increases that occur as a result of the ERE.

Oborn, B. M.; Metcalfe, P. E.; Butson, M. J.; Rosenfeld, A. B. [Illawarra Cancer Care Centre (ICCC), Wollongong, New South Wales 2500 (Australia) and Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, New South Wales 2500 (Australia); Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, New South Wales 2500 (Australia); Illawarra Cancer Care Centre (ICCC), Wollongong, New South Wales 2500 (Australia); Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, New South Wales 2500 (Australia)

2010-10-15

45

Uterine Rupture  

Microsoft Academic Search

\\u000a Uterine rupture may be defined as a disruption of the uterine muscle extending to and involving the uterine serosa or disruption\\u000a of the uterine muscle with extension to the bladder or broad ligament [1]. Uterine dehiscence is defined as disruption of\\u000a the uterine muscle with intact uterine serosa [1]. Uterine rupture is associated with severe maternal and perinatal morbidity\\u000a and

Sharon R. Sheehan; Deirdre J. Murphy

46

Effects of Heterogeneities in Strength and Initial Shear Stress on Large Ruptures in a Fast Multicycle Earthquake Simulator (RSQSim) and DYNA3D  

Microsoft Academic Search

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

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

2008-01-01

47

A Theory of Liquid Surface Rupture by a Uniform Electric Field  

Microsoft Academic Search

Surface distortion and rupture permits field emission from liquid surfaces at field strengths less than those effective for equally smooth solid surfaces. An approximate mathematical theory of the rupture of a plane liquid surface in a uniform electric field has been developed. The relation between initial distortion, rupture time, and field strength has been calculated for fields large compared to

Lewi Tonks

1935-01-01

48

Surgical treatment of distal biceps rupture.  

PubMed

Rupture of the distal biceps tendon accounts for 10% of all biceps brachii ruptures. Injuries typically occur in the dominant elbow of men aged 40 to 49 years during eccentric contraction of the biceps. Degenerative changes, decreased vascularity, and tendon impingement may precede rupture. Although nonsurgical management is an option, healthy, active persons with distal biceps tendon ruptures benefit from early surgical repair, gaining improved strength in forearm supination and, to a lesser degree, elbow flexion. Biomechanical studies have tested the strength and displacement of various repairs; the suspensory cortical button technique exhibits maximum peak load to failure in vitro, and suture anchor and interosseous screw techniques yield the least displacement. Surgical complications include sensory and motor neurapraxia, infection, and heterotopic ossification. Current trends in postoperative rehabilitation include an early return to motion and to activities of daily living. PMID:20190104

Sutton, Karen M; Dodds, Seth D; Ahmad, Christopher S; Sethi, Paul M

2010-03-01

49

Strain-Induced Splitting and Oscillator-Strength Anisotropy of the Infrared Transverse-Optic Phonon in Calcium Fluoride, Strontium Fluoride, and Barium Fluoride  

Microsoft Academic Search

Strain-induced splittings of the infrared-active TO phonon in CaF2, SrF2, and BaF2 are calculated from a least-squares fit of photoelastic dispersion data by an undamped oscillator model. The strain-induced oscillator-strength anisotropy appears negligible; the Szigeti effective charge remains a scalar. The shear deformation potential for [100] strain is ~170 cm-1 in all the materials; for [111] strain it is -82

Albert Feldman; Roy M. Waxler

1980-01-01

50

Transversity 2008  

NASA Astrophysics Data System (ADS)

Purpose and status of the Italian transversity project / F. Bradamante -- Transversity asymmetries / D. Boer -- The transverse angular momentum sum rule / E. Leader -- Measurement of Collins and Sivers asymmetries at HERMES / L. L. Pappalardo (for the HERMES collaboration) -- Review of SSA results on deuteron at COMPASS / A. Richter (for the COMPASS collaboration) -- Single spin asymmetries on a transversely polarized proton target at COMPASS / S. Levorato (for the COMPASS collaboration) -- New preliminary results on the transversity distribution and the Collins fragmentation functions / M. Anselmino ... [et al.] -- Sivers effect in SIDIS pion and kaon production / M. Anselmino ... [et al.] -- Spin-orbit correlations / M. Burkardt -- Correlation functions in hard and (semi)-inclusive processes / M. Schlegel, S. Mei[symbol]ner and A. Metz -- Transversity via exclusive [pie symbol]-electroproduction / G. R. Goldstein, S. Liuti and S. Ahmad -- Estimate of the Sivers asymmetry at intermediate energies with rescattering extracted from exclusive processes / A. Bianconi -- Exclusively produced p[symbol] asymmetries on the deuteron and future GPD measurements at COMPASS / C. Schill (for the COMPASS collaboration) -- Transversity and transverse-momentum-dependent distribution measurements from PHENIX and BRAHMS / C. Aidala (for the PHENIX and BRAHMS collaborations) -- Sivers and Collins effects in polarized pp scattering processes / M. Anselmino ... [et al.] -- Sivers function in constituent quark models / S. Scopetta ... [et al.] -- Sivers, Boer-Mulders and transversity in Drell-Yan processes / M. Anselmino ... [et al.] -- TMDs and Drell-Yan experiments at Fermilab and J-PARC / J.-C. Peng -- Double polarisation observables at PAX / M. Nekipelov (for the PAX collaboration) -- Future Drell-Yan measurement @ COMPASS / M. Colantoni (for the COMPASS collaboration) -- Measurements of unpolarized azimuthal asymmetries at COMPASS / W. Käfer (for the COMPASS collaboration) -- Measurement of azimuthal asymmetries of the unpolarized cross-section at HERMES / F. Giordano (for the HERMES collaboration) -- Measurement of transversity via an interference fragmentation function at HERMES / R. Fabbri (for the HERMES collaboration) -- Relating leading and higher twist contributions to nucleon spin structure / P. G. Ratcliffe and O. V. Teryaev -- DIS at low and high transverse momentum: matches and mismatches / A. Bacchetta ... [et al.] -- Pretzelosity distribution function h[symbol] / H. Avakian ... [et al.] -- Transverse momentum-spin correlations / L. P. Gamberg, G. R. Goldstein and M. Schlegel -- Exploring confinement with spin / J. P. Ralston -- SIDIS asymmetries in quark-diquark model / A. Kotzinian -- Parton densities in a spectator model with axial-vector diquarks / M. Radici -- Gluonic pole matrix elements in spectator models / A. Mukherjee, L. P. Gamberg and P. J. Mulders -- TMD measurements at CLAS6 and CLAS12 / H. Avakian (for the CLAS6 and CLAS12 collaborations) -- Nucleon to pion transition distribution amplitudes in a light-cone quark model / M. Pincetti, B. Pasquini and S. Boffi -- Antiproton polarization studies for FAIR (How to polarize antiprotons and what to use them for?) / H. Ströher, F. Rathmann and P. Lenisa -- No one can encompass the unencompassable: the highlights of transversity-2008 / N. N. Nikolaev.

Giuseppe, Ciullo; Paolo, Lenisa; Marco, Contalbrigo; Delia, Hasch

2009-04-01

51

What Is an Earthquake?: Fault-Rupture Analogies  

NSDL National Science Digital Library

This activity has two parts: the first part will demonstrate the weaknesses of simple fault models (like block diagrams) in depicting the process of fault rupture accurately; and the second part is centered around a fairly simple animation of rupture propagation, seen by an oblique map view, that attempts to show more accurately what we should envision when we think about fault rupture. This activity provides different analogies for describing the process of fault rupture, with attention paid to the strengths and weaknesses of each.

52

Creep-rupture of polymer-matrix composites. [graphite-epoxy laminates  

NASA Technical Reports Server (NTRS)

An accelerated characterization method for resin matrix composites is reviewed. Methods for determining modulus and strength master curves are given. Creep rupture analytical models are discussed as applied to polymers and polymer matrix composites. Comparisons between creep rupture experiments and analytical models are presented. The time dependent creep rupture process in graphite epoxy laminates is examined as a function of temperature and stress level.

Brinson, H. F.; Griffith, W. I.; Morris, D. H.

1980-01-01

53

Ruptured intracranial dermoid cysts  

Microsoft Academic Search

Summary  Rupture of intracranial dermoid cysts (RICDC) is a rare phenomenon. The mechanism of rupture, pathophysiology of fat in the\\u000a ventricles and subarachnoid spaces, possible complications, and proper management of such conditions are proposed on the basis\\u000a of a review of the literature and experience with two cases of ruptured intracranial dermoid cysts (One was in the pineal\\u000a region, while another

K. El-Bahy; A. Kotb; A. Galal; A. EL-Hakim

2006-01-01

54

Ruptured intracranial dermoid cyst  

PubMed Central

Rupture of an intracranial dermoid cyst is a rare event with considerable associated morbidity and potential mortality. We present a case of intracranial rupture of a dermoid cystic tumor with consequent dissemination of subarachnoid fat droplets resulting in acute aseptic chemical meningitis. Radiographic findings, operative treatment, and pathologic features are described.

Barnett, David W.; Snipes, George J.; Layton, Kennith F.; Opatowsky, Michael J.

2012-01-01

55

Ruptured intracranial dermoid cysts  

Microsoft Academic Search

BACKGROUNDIntracranial dermoid cysts are rare congenital neoplasms that are believed to arise from ectopic cell rests incorporated in the closing neural tube. The rupture of an intracranial dermoid cyst is a relatively rare event that typically occurs spontaneously. In the past it was believed that rupture is always fatal, a hypothesis that is not supported by more recently reported cases.

Ruediger Stendel; Terttu Aulikki Pietilä; Kerstin Lehmann; Ralf Kurth; Olaf Suess; Mario Brock

2002-01-01

56

Liposome rupture and contents release over coplanar microelectrode arrays.  

PubMed

The vulnerability of vesicles to electroporation and rupture by externally applied electric fields, combined with the ability of dielectrophoresis and/or AC electroosmosis to manipulate suspended vesicles over micropatterned electrodes suggests new techniques to electrically trigger localized chemical reactions at predetermined positions in microfluidic devices. The electric field conditions needed to rupture giant unilamellar phospholipid vesicles were determined as a function of vesicle size in a simple coplanar microelectrode array geometry. Rupture results were interpreted in terms of the spatially varying electric field strength, calculated via the Poisson equation and accounting for frequency effects on electrode impedance, and the experimentally measured vesicle elevation. The vesicle transmembrane voltage scales linearly with the applied electric field strength according to the Schwan theory of electroporation, so that larger vesicles are usually more prone to electric field induced rupture than smaller ones in the uniform electric fields that are typically employed to cause electroporation and rupture. Yet, in the coplanar microelectrode arrangement, larger vesicles preferentially reside at larger elevations where the local field strengths are weaker. As a result, there is a sensitive range of vesicle radii that are most prone to electric field induced rupture over a micropatterned electrode array that leaves the largest vesicles resistant to rupture. PMID:19136117

Lim, Jit Kang; Zhou, Hao; Tilton, Robert D

2009-04-01

57

Rupture velocity inferred from near-field differential ground motion  

NASA Astrophysics Data System (ADS)

The velocity of the rupture propagation is a fundamental source parameter that strongly affects ground motion. It is commonly assessed from kinematic inversion of strong-motion or teleseismic data, sometimes combined with InSar and/or GPS data. The obtained rupture velocity remains inevitably affected by uncertainties, mainly due to imperfect knowledge of the earth structure and tradeoffs between different source parameters. In this study we show how the analysis of differential ground-motion may help constraining the rupture velocity, without a priori information about the earth velocity structure. Our analysis is based on synthetic ground-motion simulations (0-2 Hz) for vertical strike-slip earthquakes propagating unilaterally at a fixed rupture velocity in a homogeneous elastic medium covered with a 1 km-thick low velocity layer (shear wave velocity equal to 1 km/s). We show that when the rupture reaches the bottom of the shallow layer, the phase velocity of transverse waves measured in the forward rupture direction up to a few rupture lengths is equal to the rupture velocity, for a large range of frequencies. The comparison with the phase velocity obtained for a point source then enables to retrieve the value of the rupture velocity. The phase velocity is simply computed from the ratio between the ground velocity and the shear strain or the rotation about a vertical axis. This study points out the utility of setting up dense arrays at the vicinity of major faults to retrieve rupture features such as the rupture velocity.

Causse, Mathieu; Cornou, Cécile; Bécasse, Julie; Bouchon, Michel

2014-05-01

58

Rupture Dynamics of Subduction Megathrust Earthquakes  

NASA Astrophysics Data System (ADS)

Motivated by recent megathrust earthquakes, we have begun a systematic investigation of the influence of depth-dependent frictional properties, slab geometry and fault dip angle, and strength of the accretionary prism on rupture propagation. A particular focus is on identifying the conditions under which rupture reaches the trench, as this maximizes seafloor uplift and the resulting tsunami. We tackle this problem with fully dynamic two-dimensional simulations, using a high order finite difference method with coordinate transforms to handle the complex geometry. The fault obeys rate-and-state friction and the off-fault material response includes continuum Drucker-Prager plasticity that is activated at sufficiently high stress levels. We directly account for variations in material properties across curved crust and mantle layers, since waveguide effects are an essential part of the rupture process in this geometry. For shallowly dipping faults, free surface effects are particularly pronounced. Wave reflections from the seafloor transiently decrease normal stress on the fault surface, thereby reducing its strength. We have found that this effect can be sufficient to permit rupture all the way to the trench axis, even if the upper portion of the fault is velocity-strengthening and thus incapable of unstable frictional sliding. Additionally, current thinking appears to assume that this upper part of the fault will rupture only if it is locked during the interseismic period, thereby resulting in strain accumulation in the surrounding material. Our preliminary models instead suggest that this part of the fault can still slip coseismically, even with negligible prestress. We are now exploring how robust this tentative conclusion is, as it would have significant implications for predictions of rupture extent based on observational estimates of the extent of fault locking during the interseismic period.

Dunham, E. M.; Kozdon, J. E.

2011-12-01

59

[Ruptured abdominal aortic aneurysm].  

PubMed

Rupture of the abdominal aortic aneurysm is a high lethal risk pathology, which requires precise diagnosis and urgent and efficient surgical treatment. Despite improved diagnostic capabilities (echoscopy, in specialized departments--angiography, computed tomography, magnetic nucleus resonance), mortality related to this pathology remains high in intensive care units. In the present article data concerning prevalence and clinical outcomes of the rupture of the abdominal aortic aneurysm for 1999-2001 is presented in detail. During this period 22 patients have undergone surgery due to abdominal aortic aneurysm rupture. Described are most prevalent complications, mortality rates and causes, analyzed are treatment strategy and tactics. PMID:12474751

Urbonavicius, Sigitas; Antusevas, Aleksandras

2002-01-01

60

Partial Rotator Cuff Ruptures  

Microsoft Academic Search

\\u000a Partial rotator cuff ruptures are not rare and occur mainly in the supraspinatus tendon and may extend to that of infraspinatus,\\u000a but rarely to the tendon of subscapularis. Isolated lesions in the tendons of infraspinatus, teres minor or subscapularis\\u000a are rare. Partial ruptures usually occur before the sixth decade of life and can be a cause of unexplained pain in

Antonio Cartucho

61

Incomplete Cesarean Scar Rupture  

PubMed Central

Background Uterine rupture at the site of a previous cesarean scar is an uncommon but catastrophic complication of pregnancy, which is associated with significant maternal and fetal morbidity and mortality. Case Presentation A 30-year old woman at 24th week of gestation and complaint of pain, contractions and spotting was admitted in Royan Institute in Tehran, Iran. She had a past medical history of an EP and a cesarean section delivery, respectively 4 and 2 years before hospitalization. Herniation of an amniotic membrane into the maternal bladder was found on ultrasound examination. Conclusion Risk factors of cesarean scar rupture should be considered in women undergoing subsequent pregnancies as they need extra care. Ultrasonography can be used to evaluate women with previous cesarean section to assess the risks of scar rupture during subsequent pregnancies.

Ahmadi, Firoozeh; Siahbazi, Shiva; Akhbari, Farnaz

2013-01-01

62

Clinical recovery of two hip adductor longus ruptures: a case-report of a soccer player  

PubMed Central

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 adductor longus ruptures, using novel, reliable and validated assessment methods. Case presentation A 22-year old male soccer player (Caucasian) sustained two subsequent acute adductor longus ruptures, one in each leg. The injuries occurred 10 months apart, and were treated non-surgically in both situations. He was evaluated using hip-strength assessments, self-report and ultrasonography until complete muscle-strength recovery of the hip adductors had occurred. The player was able to participate in a full soccer training session without experiencing pain 15 weeks after the first rupture, and 12 weeks after the second rupture. Full hip adductor muscle-strength recovery was obtained 52 weeks after the first rupture and 10 weeks after the second rupture. The adductor longus injuries, as verified by initial ultrasonography (10 days post-injury), showed evidence of a complete tendon rupture in both cases, with an almost identical imaging appearance. It was only at 6 and 10 weeks ultrasonographic follow-up that the first rupture was found to include a larger anatomical area than the second rupture. Conclusion From this case we can conclude that two apparently similar hip adductor longus ruptures, verified by initial ultrasonography (10 days post-injury), can have very different hip adductor strength recovery times. Assessment of adductor strength recovery may therefore in the future be a useful and important additional measure for determining when soccer players with hip adductor longus ruptures can return safely to play.

2013-01-01

63

[Indirect traumatic diaphragmatic rupture].  

PubMed

Between 1969 and 1988 51 polytraumatized patients were treated for rupture of the diaphragm due to blunt trauma. In 39 cases the lesion was in the left hemidiaphragm, in 11 cases on the right side and in one case on both sides. Clinical investigation and posterior-anterior chest X-ray were the most important diagnostic procedures. A high percentage of ruptures was only detected intraoperatively during acute laparotomy/thoracotomy. Early or delayed surgery had no influence on the survival of patients. The prognosis depends on the severity of associated injuries, which are the main causes of death in these patients. PMID:1858376

Holzberger, P; Königsrainer, A; Tauscher, T; Müller, L; Thöni, H

1991-01-01

64

Splenic abscess rupture postappendicectomy  

PubMed Central

The authors present a case of splenic abscess rupture postappendicectomy. Splenic abscess is rare with a reported incidence of 0.05%–0.7%. It is extremely unusual for a splenic abscess to result in splenic rupture. Contiguous spread, in this case from postappendix perforation, can cause splenic abscess formation. Postemergency splenectomy, the patient required admission to intensive therapy unit for 5 days but made a good postoperative recovery. This case is important to report as this is a rare postoperative complication of generalised peritonitis and this case highlights that astute diagnosis and management of the deteriorating surgical patient and rapid mobilisation of theatre are lifesaving.

Patel, Roshani; Pai, Aakash; Al-Shoek, Ihsan; Evans, Charles; Gordon, Andrew

2012-01-01

65

Creep rupture testing of carbon fiber-reinforced epoxy composites  

NASA Astrophysics Data System (ADS)

Carbon fiber is becoming more prevalent in everyday life. As such, it is necessary to have a thorough understanding of, not solely general mechanical properties, but of long-term material behavior. Creep rupture testing of carbon fiber is very difficult due to high strength and low strain to rupture properties. Past efforts have included testing upon strands, single tows and overwrapped pressure vessels. In this study, 1 inch wide, [0°/90°]s laminated composite specimens were constructed from fabric supplied by T.D. Williamson Inc. Specimen fabrication methods and gripping techniques were investigated and a method was developed to collect long term creep rupture behavior data. An Instron 1321 servo-hydraulic material testing machine was used to execute static strength and short term creep rupture tests. A hanging dead-weight apparatus was designed to perform long-term creep rupture testing. The testing apparatus, specimens, and specimen grips functioned well. Collected data exhibited a power law distribution and therefore, a linear trend upon a log strength-log time plot. Statistical analysis indicated the material exhibited slow degradation behavior, similar to previous studies, and could maintain a 50 year carrying capacity at 62% of static strength, approximately 45.7 ksi.

Burton, Kathryn Anne

66

Transverse plane gait problems in children with cerebral palsy.  

PubMed

Transverse plane deviations are significant contributors to pathologic gait in children with cerebral palsy (CP). Due to limitations in neuromuscular control, balance, strength and coordination, transverse plane gait deviations are poorly tolerated in these children. Transverse plane malalignment results in lever arm dysfunction and can be seen with either intoeing or out-toeing. Frequent causes of transverse plane problems and lever arm dysfunction include long bone (femoral and/or tibial) torsion, pelvic rotation, and pes varus or valgus. Computerized motion analysis facilitates accurate identification of transverse plane abnormalities. This article addresses appropriate identification and treatment of transverse plane gait deviations in children with CP. PMID:23653033

Rethlefsen, Susan A; Kay, Robert M

2013-06-01

67

Premature Rupture of Membranes  

PubMed Central

The management of premature rupture of the amniotic membranes before 37 weeks gestation remains controversial. The authors of this article outline the risks involved for the fetus, define the various terms related, and discuss the antepartum and intrapartum management of such an event and offer a protocol that they have developed.

Akierman, Albert; Iwanicki, Stanislaw

1988-01-01

68

The effect of the interphase/interface region on creep and creep rupture of thermoplastic composites  

SciTech Connect

The effect of the interphase/interface region on the static mechanical properties, creep and creep rupture behavior of thermoplastic (J2) composites was investigated. The mechanical properties of the J2 composites were altered by systematic changes in fiber surface chemistry. Four fiber systems were used including the AU4, AS4(1) (2), and AS4CGP fibers. (AS4(1) and AS4(2) represent different batch numbers.) Surface energies and chemistry of carbon fibers were examined using the Dynamic Contact Angle (DCA) method and X-ray Photoelectron Spectroscopy (XPS), respectively. The mesoindentation technique was used to measure the interfacial shear strengths (ISS) of the composites. For the same batch of the composites, the ISS ratios for AS4(2)/J2 to AU4/J2 and AS4CGP/J2 to AU4/J2 were 1.22 and 1.24, respectively. The mechanical properties of these composites in the fiber direction were insensitive to the ISS. The transverse and shear moduli of the J2 composites were also not affected by the ISS. The static strengths, in general, ordered themselves from strong to weak as follows: AS4(2)/J2 greater than AS4CGP/J2 is greater than AU4/J2. However, the creep rupture strength revealed a different ordering: AS4CGP/J2 is greater than AS4(2)/J2 is greater than AU4/J2. This suggests that static mechanical properties may not be a good indicator for long term mechanical performance. Experimental results showed that the interphase/interface region did not affect the degradation rates of the creep rupture strength of the J2 composites. DMA creep tests were performed at elevated temperatures for J2 composites. A master curve of each composite was generated. The shift factors obeyed the Arrhenius type equation. The activation energies of composites were approximately the same. The creep response of the AU4/J2, AS4(2)/J2, and AS4CGP/J2 composites were not dependent upon the ISS. Severe delaminations were observed in the AS4(1)/J2 composite laminates.

Chang, Y.S.

1992-01-01

69

Earthquake in a Maze: Compressional Rupture Branching During the 2012 Mw 8.6 Sumatra Earthquake  

NASA Astrophysics Data System (ADS)

Seismological observations of the 2012 moment magnitude 8.6 Sumatra earthquake reveal unprecedented complexity of dynamic rupture. The surprisingly large magnitude results from the combination of deep extent, high stress drop, and rupture of multiple faults. Back-projection source imaging indicates that the rupture occurred on distinct planes in an orthogonal conjugate fault system, with relatively slow rupture speed. The east-southeast-west-northwest ruptures add a new dimension to the seismotectonics of the Wharton Basin, which was previously thought to be controlled by north-south strike-slip faulting. The rupture turned twice into the compressive quadrant, against the preferred branching direction predicted by dynamic Coulomb stress calculations. Orthogonal faulting and compressional branching indicate that rupture was controlled by a pressure-insensitive strength of the deep oceanic lithosphere.

Meng, L.; Ampuero, J.-P.; Stock, J.; Duputel, Z.; Luo, Y.; Tsai, V. C.

2012-08-01

70

Quantitative relations between earthquake source properties from dynamic rupture simulations incorporating off-fault plasticity  

NASA Astrophysics Data System (ADS)

High stress concentrations at earthquake rupture fronts may generate inelastic off-fault response around the rupture tip, leading to increased energy absorption in the damage zone. Accounting for off-fault plasticity in earthquake rupture simulations imposes physical limits on extreme ground motion as plastic dissipation limits the rupture speed and peak slip rate of pulses. We present physics-based relations between earthquake source parameters derived from analytic considerations and from a consistent set of 2D dynamic rupture models that incorporate severe velocity-weakening friction and off-fault plasticity assuming homogeneous initial conditions. Specifically, we deduce a non-linear relation between the peak slip velocity and rupture speed, which holds for sub- and super-shear, crack- and pulse-like ruptures. We find that these relations are statistically consistent with the correlation of peak slip rate and rupture speed in 3D dynamic rupture models under linear slip weakening friction and highly heterogeneous initial stress. Furthermore the closeness to failure (CF) parameter introduced by Templeton and Rice (2008) is an adequate predictor of rupture speed for slow ruptures, whereas rupture speeds larger than ~80% S-wave speed have a more complicated dependence on stress orientation and the relative strength of the fault. These relations, combined with the limits on rupture speed imposed by off-fault plasticity, may encapsulate a major influence of plastic deformation on near-field ground motions. Our study captures fundamental processes governing dynamic rupture propagation coupled to self-similar off-fault energy dissipation. Thus, our results may be a suitable starting point to develop new pseudo-dynamic source parametrizations for source inversion and ground motion prediction that account for off-fault plasticity. We will report on the suitability of these relations in the presence of other sources of rupture complexity, e.g. coalescing rupture fronts.

Gabriel, Alice; Ampuero, Jean-Paul; Dalguer, Luis A.; Mai, P. Martin

2013-04-01

71

Design shear strength formula for high strength concrete beams  

Microsoft Academic Search

After a brief review on the concrete shear strength mechanisms, two very reliable expressions for predicting the shear strength\\u000a of beams without transverse reinforcement are reported: the one proposed by Bažant and Kim [7], which is valid for Normal\\u000a strength Concrete (NSC) beams, and the other recently proposed by the authors, which is valid for High Strength Concrete (HSC)\\u000a beams.

G. Russo; G. Somma; P. Angeli

2004-01-01

72

Creep Rupture Properties of Welded Joints of Heat Resistant Steels  

NASA Astrophysics Data System (ADS)

In this study, the high-temperature mechanical and creep rupture properties of Grade 91/Grade 91 (Mod. 9Cr-Mo) similar welded joints and Grade 91/Inconel 82/SUS304 dissimilar welded joints were examined. The effects of temperature and stress on the failure location in the joints were also investigated. Creep rupture tests were conducted at 823, 873, and 923 K; the applied stress ranges were 160-240, 80-160, and 40-80 MPa, respectively. The creep rupture strengths of the specimens with welded joints were lower than those of the specimens of the base metal at all temperature levels; in addition, these differences in creep strength increased with temperature. After being subjected to long-term creep rupture tests, the fracture type exhibited by the dissimilar welded joints was transformed from Types V and VII to Type IV. It was estimated that the fracture type exhibited by the dissimilar welded joints after 100,000-h rupture strength tests at 823 K and 873 K was Type IV fracture.

Yamazaki, Masayoshi; Watanabe, Takashi; Hongo, Hiromichi; Tabuchi, Masaaki

73

Seismological evidence and dynamic model of reverse rupture propagation during the 2010 M7.2 El Mayor Cucapah earthquake  

NASA Astrophysics Data System (ADS)

The 2010 El Mayor-Cucapah earthquake has produced some unique observations that exemplify the complexity of rupture dynamics. An eyewitness located near the fault when the rupture broke reported signatures of reverse surface rupture (rupture towards the South at a location North from the hypocenter). We report here on seismological evidence of this phenomenon and present dynamic rupture simulations that illustrate a possible mechanism. Reverse rupture propagation is not admissible in traditional source inversions, because of restrictive assumptions about the rupture kinematics adopted to reduce the non-uniqueness of the inverse problem. In contrast, source imaging by back-projection of dense array data is free from such assumptions. Recently, we have enhanced the array back-projection technique to achieve higher resolution on rupture evolution. We have also extended this approach to recordings at regional distance, despite the complexity of the regional Pn waveforms. We imaged the source of the El Mayor-Cucapah earthquake by back-projecting Pn waves recorded by the SIEDCAR array in New Mexico. Our analysis reveals a segment with reverse rupture propagation consistent with the eyewitness reports. Our simulations of dynamic earthquake rupture show that reverse rupture propagation can be caused by delayed rupture of a strong fault region with a negative along-strike gradient of strength excess. In this scenario the rupture front tunnels through (or surrounds) the strong area, then starts breaking the opposite, weaker end of the strong patch, inducing a reverse rupture front.

Meng, L.; Ampuero, J. P.; Page, M. T.; Hudnut, K. W.

2011-12-01

74

Creep rupture properties of a Ni-Cr-W superalloy in air environment.  

National Technical Information Service (NTIS)

Creep rupture properties in air environment were investigated at 900, 1000 and 1050degC using bar, plate and seamless tube materials of a Ni-Cr-W superalloy developed for use at service temperatures around 1000degC. Long-term creep rupture strength was es...

Y. Kurata H. Tsuji M. Shindo H. Nakajima

1996-01-01

75

Dynamic Rupture Process of the 1999 Chi-Chi Earthquake  

NASA Astrophysics Data System (ADS)

Earthquake source dynamics provides key elements for the prediction of strong ground motion and for understanding the physics of earthquake processes. This research investigates the characteristics of dynamic source rupture process of the 1999 Chi-Chi earthquake by using a 3D finite difference method with variable grid spacing. A new algorithm is proposed to deal with a non-planar fault model. This approach does not require aligning the fault plane to the finite-difference grid for implementation of FDM and provide a method to deal with a more realistically irregular geometry fault model. We apply this approach to the 1999 Chi-Chi earthquake with a curved fault surface and rebuild the dynamic source rupture process for this larger earthquake. Our results show that for the Chi-Chi earthquake, the behaviors of the most of the subfaults followed a slip-weakening friction law during rupture. And the distributions of the dynamic source parameters estimated from the kinematic results are quite heterogeneous. For the dynamic rupture process, this study reveals the rupture propagation jumping phenomenon which is difficult to be simulated in kinematic modeling. That is when the propagation front encountered a zone with a high strength excess, the rupture would pause to accumulate more energy to break it. Meanwhile, if there are low strength excess zones around the barrier, the propagation front would jump over the barrier to break the low strength excess zones and leave the high strength barrier unbroken. Such phenomenon of the high strength excess barriers intend to delay the propagation front can be seen clearly in the dynamic model. Using a thick fault zone model, the dynamic model discovers that the slip on the hanging-wall side is larger than that on the food-wall side and the northern parts have the longer source duration that the southern parts and these northern parts have an extreme large slip. Based on the dynamic source rupture model, the strong ground motions near the fault surface breaks are simulated in frequency range of 0.05 to 0.5 Hz. In general, the synthetic velocity waveforms agree well with the observed records for most stations. The dynamic source model successfully simulates the distinctive velocity pulse for the stations in the forward rupture direction. Also our dynamic source model successfully reproduced the waveforms as well as the distinctive velocity pulses for the station nearby or on the fault surface breaks. These results demonstrate that our dynamic source model can reproduce the main features of long period ground motions; hence, lead us to a better understanding on the source rupture process of the Chi-Chi earthquake.

Zhang, W.; Iwata, T.; Irikura, K.; Pitarka, A.; Sekiguchi, H.

2003-12-01

76

Distal biceps tendon rupture  

Microsoft Academic Search

The authors report a rupture of the distal tendon of biceps brachii in a 42-year-old athlete. Magnetic resonance imaging confirmed the injury. Early surgical repair was performed by reinsertion of the tendon on the radial tuberosity according to modified Boyd-Anderson technique. Indomethacin was administered prophylactically. No complications were noted. At the latest follow-up, the patient had full elbow range of

Olga D. Savvidou; Panayiotis J. Papagelopoulos; Andreas F. Mavrogenis; Antonios A. Partsinevelos; Evangelos J. Karadimas; Demetrios S. Korres

2004-01-01

77

Role of Fault Branches in Earthquake Rupture Dynamics  

NASA Astrophysics Data System (ADS)

We analyze earthquake ruptures propagating along a straight "main" fault and encountering a finite-length branch fault. Such intersections are often observed in natural fault systems. The predicted effects of the interaction with the branch that we report can be remarkable; they can strongly perturb the propagation velocity on the main fault and, in some cases, even arrest that propagation. Earlier work [Poliakov et al., 2002, Kame et al., 2003; Bhat et al., 2004] emphasized the role of the fault pre-stress state, branch geometry (i.e., branching angle), and the incoming rupture velocity at the branching junction in determining whether the rupture would follow the branch or continue on the main fault or both, through simulations which did not let a rupture on the branch encounter a barrier or a fault end (called "infinite" branch cases henceforth). In this study we look at "finite" branch cases, and study the effect also of branch length, with rupture being blocked from propagation beyond the branch end. It is known that sudden stoppage of a dynamic rupture front leads to the propagation of large dynamic stress perturbations in the medium. These have been known to nucleate ruptures on adjacent fault segments [Harris and Day, 1983, Harris et al., 2001,Fliss et al., 2004, among others]. We thus anticipate interaction between the rupture on the main fault and the branched one at two stages, namely, when the rupture is propagating on the branch and when it is suddenly blocked at the branch end. We show that in general rupture termination on a compressional branch little affects propagation on the main fault compared to the infinite branch cases. For branches on the extensional side, we show in some cases that whereas an infinite branch would have allowed (or stopped) rupture propagation on the main fault, a finite branch stops (or allows) propagation on the main fault. Such results have a dependence on branch length that we document. We also illustrate branch-related complexities in rupture velocity evolution which could be one of the sources of the high-frequency content of strong ground motion records. Complexities in the slip distribution, often associated with a presumed heterogeneous strength distribution along the fault, can also be observed when rupture is terminated on a branch.

Bhat, H. S.; Dmowska, R.; Olives, M.; Rice, J. R.

2006-12-01

78

Role of fault branches in earthquake rupture dynamics  

NASA Astrophysics Data System (ADS)

We analyze earthquake ruptures propagating along a straight "main" fault and encountering a finite-length branch fault. Such intersections are often observed in natural fault systems. The predicted effects of the interaction with the branch that we report can be remarkable; they can strongly perturb the propagation velocity on the main fault and, in some cases, even arrest that propagation. Earlier work (Kame et al., 2003; Bhat et al., 2004) emphasized the role of the fault pre-stress state, branch geometry (i.e., branching angle), and the incoming rupture velocity at the branching junction in determining whether the rupture would follow the branch or continue on the main fault or both, through simulations which did not let a rupture on the branch encounter a barrier or a fault end (called `infinite' branch cases henceforth). In this study we look at "finite" branch cases, and study the effect also of branch length, with rupture being blocked from propagation beyond the branch end. It is known that sudden stoppage of a dynamic rupture front leads to the propagation of large dynamic stress perturbations in the medium. These have been known to nucleate or terminate ruptures on adjacent fault segments (Harris et al., 1991; Harris and Day, 1993, 1999; Harris et al., 2002; Fliss et al., 2005, among others). We thus anticipate interaction between the rupture on the main fault and the branched one at two stages, when the rupture is propagating on the branch and when it is suddenly blocked at the branch end. We show that in general rupture termination on a compressional branch little affects propagation on the main fault compared to the infinite branch cases. For branches on the extensional side, we show in some cases, that whereas an infinite' branch would have allowed (or stopped) rupture propagation on the main fault, a finite branch stops (or allows) propagation on the main fault. Such results have a dependence on branch length that we document. We also illustrate branch-related complexities in rupture velocity evolution which could be one of the sources of the high-frequency content of strong ground motion record. Complexities in the slip distribution, often associated with a presumed heterogeneous strength distribution along the fault, can also be observed when rupture is terminated on a branch.

Bhat, Harsha S.; Olives, Marion; Dmowska, Renata; Rice, James R.

2007-11-01

79

Paralabral rupture of the proximal biceps tendon from light weightlifting.  

PubMed

Rupture of the long head of the biceps is usually seen in older adults, in conjunction with rotator cuff tears or tenosynovitis secondary to chronic subacromial impingement; it is rarely seen as a result of trauma. We present the case of a young active patient who denied prodromal symptoms but ruptured the long head of the biceps brachii tendon (LHB) while performing 25-pound biceps curls. Upon examination, the patient was noted to have a readily apparent biceps defect and decreased strength. He was brought to the operating room, where open subpectoral tenodesis of the LHB was performed. At the 6-week follow-up evaluation, the patient had regained full range of motion. By 6 months, he had regained his previous strength. This case demonstrates an unusual presentation of a LHB rupture in a young healthy man with no prodromal symptoms. PMID:19149346

Miller, Kyle E; Solomon, Daniel J

2008-12-01

80

Oxidation induced stress-rupture of fiber bundles  

SciTech Connect

The effect of oxidation on the stress-rupture behavior of fiber bundles was modeled. It is shown that oxidation-induced fiber strength degradation results in the delayed failure of the associated fiber bundle and that the fiber bundle strength decreases with time as t{sup {minus}1/4}. It is also shown that the temperature dependence of the bundle loss of strength reflects the thermal dependence of the mechanism controlling the oxidation of the fibers. The effect of gauge length on the fiber bundle strength was also analyzed. Numerical examples are presented for the special case of Nicalon{trademark} fibers.

Lara-Curzio, E.

1997-03-01

81

Composite Stress Rupture NDE Research and Development Project (Kevlar[R] and Carbon)  

NASA Technical Reports Server (NTRS)

The objective was to develop and demonstrate nondestructive evaluation (NDE) techniques capable of assessing stress rupture related strength degradation for carbon composite pressure vessels, either in a structural health monitoring (SHM) or periodic inspection mode.

Saulsberry, Regor

2010-01-01

82

Transversity: Theory and phenomenology  

SciTech Connect

The distribution of transversely polarized quarks inside a transversely polarized nucleon, known as transversity, encodes a basic piece of information on the nucleon structure, sharing the same status with the more familiar unpolarized and helicity distributions. I will review its properties and discuss different ways to access it, with highlights and limitations. Recent phenomenological extractions and perspectives are also presented.

D'Alesio, Umberto [Dipartimento di Fisica, Universita di Cagliari, Cittadella Universitaria, and Istituto Nazionale di Fisica Nucleare, Sezione di Cagliari, C. P. 170, I-09042 Monserrato (Italy)

2013-04-15

83

Effects of Pre-Stress State and Rupture Velocity on Dynamic Fault Branching  

NASA Astrophysics Data System (ADS)

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, http://esag.harvard.edu/dmowska/PDR.pdf], 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. Natural examples seem consistent with the simulations we present.

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

2002-12-01

84

[Achilles tendon rupture].  

PubMed

The treatment of acute of Achilles tendon rupture experienced a dynamic development in the last ten years. Decisive for this development was the application of MRI and above all the ultrasonography in the diagnostics of the pathological changes and injuries of tendons. The question of rupture morphology as well as different courses of healing could be now evaluated objectively. These advances led consequently to new modalities in treatment concepts and rehabilitation protocols. The decisive input for improvements of the outcome results and particularly the shortening of the rehabilitation period came with introduction of the early functional treatment in contrast to immobilizing plaster treatment. In a prospective randomized study (1987-1989) at the Trauma Dept. of the Hannover Medical School could show no statistical differences comparing functional non-operative with functional operative therapy with a special therapy boot (Variostabil/Adidas). The crucial criteria for therapy selection results from the sonographically measured position of the tendon stumps in plantar flexion (20 degrees). With complete adaptation of the tendons' ends surgical treatment does not achieve better results than non-operative functional treatment in term of tendon healing and functional outcome. Regarding the current therapeutic standards each method has is advantages and disadvantages. Both, the operative and non-operative functional treatment enable a stable tendon healing with a low risk of re-rupture (1-2%). Meanwhile there is consensus for early functional after-treatment of the operated Achilles' tendons. There seems to be a trend towards non-operative functional treatment in cases of adequate sonographical findings, or to minimal invasive surgical techniques. PMID:10798233

Thermann, H; Hüfner, T; Tscherne, H

2000-03-01

85

Blood vessel rupture by cavitation  

PubMed Central

Cavitation is thought to be one mechanism for vessel rupture during shock wave lithotripsy treatment. However, just how cavitation induces vessel rupture remains unknown. In this work, a high-speed photomicrography system was set up to directly observe the dynamics of bubbles inside blood vessels in ex vivo rat mesenteries. Vascular rupture correlating to observed bubble dynamics were examined by imaging bubble extravasation and dye leakage. The high-speed images show that bubble expansion can cause vessel distention, and bubble collapse can lead to vessel invagination. Liquid jets were also observed to form. Our results suggest that all three mechanisms, vessel distention, invagination and liquid jets, can contribute to vessel rupture.

Chen, Hong; Brayman, Andrew A.; Bailey, Michael R.

2011-01-01

86

Stress-rupture behavior of small diameter polycrystalline alumina fibers  

NASA Technical Reports Server (NTRS)

Continuous length polycrystalline alumina fibers are candidates as reinforcement in high temperature composite materials. Interest therefore exists in characterizing the thermomechanical behavior of these materials, obtaining possible insights into underlying mechanisms, and understanding fiber performance under long term use. Results are reported on the time-temperature dependent strength behavior of Nextel 610 and Fiber FP alumina fibers with grain sizes of 100 and 300 nm, respectively. Below 1000 C and 100 hours, Nextel 610 with the smaller grain size had a greater fast fracture and rupture strength than Fiber FP. The time exponents for stress-rupture of these fibers were found to decrease from approximately 13 at 900 C to below 3 near 1050 C, suggesting a transition from slow crack growth to creep rupture as the controlling fracture mechanism. For both fiber types, an effective activation energy of 690 kJ/mol was measured for rupture. This allowed stress-rupture predictions to be made for extended times at use temperatures below 1000 C.

Yun, Hee Mann; Goldsby, Jon C.; Dicarlo, James A.

1993-01-01

87

Strength enhancement process for prealloyed powder superalloys  

NASA Technical Reports Server (NTRS)

A technique involving superplastic processing and high pressure autoclaving was applied to a nickel base prealloyed powder alloy. Tensile strengths as high as 2865 MN/sq m at 480 C were obtained with as-superplastically deformed material. Appropriate treatments yielding materials with high temperature tensile and stress rupture strengths were also devised.

Waters, W. J.; Freche, J. C.

1977-01-01

88

Predicting rupture arrests, rupture jumps and cascading earthquakes  

NASA Astrophysics Data System (ADS)

The devastation inflicted by recent earthquakes demonstrates the danger of under-predicting the size of earthquakes. Unfortunately, earthquakes may rupture fault-sections larger than previously observed, making it essential to develop predictive rupture models. We present numerical models based on earthquake physics and fault zone data, that determine whether a rupture on a segmented fault could cascade and grow into a devastating, multisegment earthquake. We demonstrate that weakened (damaged) fault zones and bi-material interfaces promote rupture propagation and greatly increase the risk of cascading ruptures and triggered seismicity. This result provides a feasible explanation for the outstanding observation of a very large (10 km) rupture jump documented in theMW7.8 2001 Kunlun, China earthquake. However, enhanced inter-seismic deformation and energy dissipation at fault tips suppress rupture propagation and may turn even small discontinuities into effective earthquake barriers. By assessing fault stability, identifying rupture barriers and foreseeing multisegment earthquakes, we provide a tool to improve earthquake prediction and hazard analysis.

Finzi, Y.; Langer, S.

2012-12-01

89

Laminates Reinforced By Short Transverse Rods  

NASA Technical Reports Server (NTRS)

Short transverse rods incorporated into laminated composite panels to increase interlaminar strengths of panels, according to proposal. Rods help panels resist delamination caused by impacts from dropped tools or, in vehicles, by debris. Inserted into selected individual internal layers during preimpregnation.

Farley, Gary L.

1993-01-01

90

[Ruptured abdominal aortic aneurysms].  

PubMed

Eighty two aortic replacements of ruptured abdominal aortic aneurysms have been performed during the last 6 years. There were 72 male and 10 female patients, and the average age was 71.33 years. Hemorrhagic shock on the admission was observed in 45 patients, and 13 have been operated urgently without any diagnostic procedures. The transperitoneal approach have been used for the operation. Two aorto duodenal and one aorto caval fistulas, have been found. Only exploration (three patients died immediately after laparotomy and 6 after cross clamping) has been done in 9 cases, and the aortic replacement in 70 cases (27 with tubular, and 43 with bifurcated graft). In 3 cases and axillobifemoral bypass had to be done. During the operation eleven patients died, and 30 in postoperative period, during the period between one and 40 days. Total intrahospital mortality rate was 50%, compared with 3.5% for 250 electively operated patients with abdominal aortic aneurysms in same period. In postoperative period the most important cause of death was multiple organs failures. Statistically significant greater mortality rate (p > 0.01%) was found in cases of late operative treatment, hemorrhagic shock, intra-operational bleeding, ruptured front wall, suprarenal cross clamping and in patients older than 75 year. In complicated cases such as juxtarenal aneurysm, 3 sutures parachute technique for proximal anastomosis, a temporary transection of the left renal vein, and intraaortal balloon occlusive catheter for proximal bleeding control are recommended. PMID:10951761

Lotina, S I; Davidovi?, L B; Kosti?, D M; Stojanov, P L; Velimirovi?, D B; Djuki?, P L; Cinara, I S; Vojnovi?, B M; Savi?, D V

91

Effects of heterogeneous frictional properties on spontaneous rupture propagation in the 1999 Hector Mine earthquake  

NASA Astrophysics Data System (ADS)

Spontaneous rupture propagation along geometrically complex faults is an important topic because geometrical complexities may control rupture extent and path. Most of previous dynamic rupture models assume uniform frictional properties along a complex fault system. In this study, we examine how non-uniform frictional properties affect rupture path and extent. In particular, we take the fault geometry of the 1999 Hector Mine earthquake as an example. We investigate what combinations of heterogeneous static and dynamic frictional coefficients allow the rupture to propagate onto the branched and bent fault system as it did in the 1999 event in a 2D plane-strain framework, with an assumption of a uniform regional stress field. We find that larger static and smaller dynamic frictional coefficients on the northwest and southeast segments, compared with those on the north segment, can allow rupture to propagate onto all segments of the fault system, if the rupture starts on the northwest segment and near the junction with the north segment. This suggests that heterogeneities in fault strength and stress drop can play an important role in controlling rupture path and extent along geometrically complex faults. Response of nearby pre-existing compliant fault zones, including the Calico, Pinto Mountain, Rodman, Landers faults, to the 1999 Hector Mine rupture is under investigation using the advanced spontaneous rupture models.

Kang, J.; Duan, B.

2010-12-01

92

Pulse-like ruptures induced by low-velocity fault zones  

NASA Astrophysics Data System (ADS)

Low-velocity fault zones (LVFZs) are found in most mature faults. They are usually 100-400 m wide and have ˜20%-60% wave velocity reductions relative to the country rock. To study the effect of LVFZs on earthquake rupture and the radiated wavefield, we conducted two-dimensional (2-D) simulations of dynamic rupture on faults that bisect a LVFZ, considering a range of velocity reductions and widths. Most earthquakes apparently have slip rise times much shorter than their overall rupture duration. A number of dynamic mechanisms for such pulse-like ruptures have been proposed, including frictional self-healing, fault strength heterogeneities, and bimaterial effects. We find that ruptures in LVFZs with strong enough wave velocity contrast behave as pulses. These pulses are generated by fault locking induced by waves reflected from the boundaries of the LVFZ. This mechanism of pulse generation is robust to variations of initial stress, smoothness of the LVFZ structure, rupture mode, and exclusion of frictional healing. Moreover, we find that LVFZs can generate complex rupture patterns. LVFZs with low-velocity reduction induce multiple rupture fronts involving coexisting pulses and cracks. LVFZs with certain widths can accelerate the transition to supershear rupture speed. These additional effects of LVFZs on dynamic rupture can contribute to the complexity of high-frequency ground motions.

Huang, Yihe; Ampuero, Jean-Paul

2011-12-01

93

Strength of Multiple Parallel Biological Bonds  

SciTech Connect

Multivalent interactions play a critical role in a variety of biological processes on both molecular and cellular levels. We have used molecular force spectroscopy to investigate the strength of multiple parallel peptide-antibody bonds using a system that allowed us to determine the rupture forces and the number of ruptured bonds independently. In our experiments the interacting molecules were attached to the surfaces of the probe and sample of the atomic force microscope with flexible polymer tethers, and unique mechanical signature of the tethers determined the number of ruptured bonds. We show that the rupture forces increase with the number of interacting molecules and that the measured forces obey the predictions of a Markovian model for the strength of multiple parallel bonds. We also discuss the implications of our results to the interpretation of force spectroscopy measurements in multiple bond systems.

Sulchek, T A; Friddle, R W; Noy, A

2005-12-07

94

Ruptured Abdominal AorticAneurysm  

Microsoft Academic Search

Background and Purpose: A ruptured abdominal aortic aneurysm is one of the most urgent surgical conditions with high mortality. The aim of the present study was to define relevant prognostic predictors for the outcome of surgical treatment. Patients and Methods: This study included 229 subsequent patients (83% males, 17% females, age 67.0 ± 7.5 years) with a ruptured abdominal aortic

Miroslav Markovi?; Lazar Davidovi?; Živan Maksimovi?; Dušan Kosti?; Ilijas ?inara; Slobodan Cvetkovi?; Radomir Sindjelic; Petar M. Seferovi?; Arsen D. Risti?

2004-01-01

95

Plantar Fascia Ruptures in Athletes  

Microsoft Academic Search

Objective: To educate sports medicine practitioners as to length of time for an athlete to return to activity after sustaining a rupture of the plantar fascia.Methods: Athletic patients sustaining plantar fascia ruptures and subsequent treatment were reviewed. Diagnosis was based on clinical findings, although radiographic studies were done. Patients were treated for 2 to 3 weeks with a below-knee or

Amol Saxena; Brian Fullem

2004-01-01

96

Consequential rupture of gas pipeline  

Microsoft Academic Search

In the earlier part of the year 2003, various pipeline ruptures were caused by sabotage activities in the southern part of Pakistan. The event being presented in this paper was fascinating because a pipe, which was blasted with the help of explosives, subsequently caused another pipe (buried 20ft away) to rupture through slow and gradual consequential erosion. On 8 April

F. Hasan; J. Iqbal

2006-01-01

97

Acute Achilles tendon rupture in badminton players.  

PubMed

All patients with badminton-related acute Achilles tendon ruptures registered during 1990 to 1994 at the University Hospital of Umeå were retrospectively followed up using a questionnaire. Thirty-one patients (mean age, 36.0 years), 27 men and 4 women, were included. Thirty patients (97%) described themselves as recreational players or beginners. The majority of the injuries (29 of 31, 94%) happened at the middle or end of the planned game. Previous local symptoms had been noticed by five patients (16%). Long-term results showed that patients treated with surgery had a significantly shorter sick leave absence than patients treated without surgery (50 versus 75 days). There was no obvious selection favoring any treatment modality. None of the surgically treated patients had reruptures, but two reruptures occurred in the nonsurgically treated group. There seemed to be fewer remaining symptoms and a higher sports activity level after the injury in the surgically treated group. Our results indicate that local muscle fatigue may interfere with strength and coordination. Preventive measures such as specific treatment of minor injuries and adequate training of strength, endurance, and coordination are important. Our findings also indicate that surgical treatment and careful postoperative rehabilitation is of great importance among badminton players of any age or sports level with Achilles tendon rupture. PMID:9617415

Fahlström, M; Björnstig, U; Lorentzon, R

1998-01-01

98

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

NASA Astrophysics Data System (ADS)

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.

Gabriel, A.-A.; Ampuero, J.-P.; Dalguer, L. A.; Mai, P. M.

2012-09-01

99

Ruptured thought: rupture as a critical attitude to nursing research.  

PubMed

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. PMID:24741691

Beedholm, Kirsten; Lomborg, Kirsten; Frederiksen, Kirsten

2014-04-01

100

Earthquake in a maze: compressional rupture branching during the 2012 M(w) 8.6 Sumatra earthquake.  

PubMed

Seismological observations of the 2012 moment magnitude 8.6 Sumatra earthquake reveal unprecedented complexity of dynamic rupture. The surprisingly large magnitude results from the combination of deep extent, high stress drop, and rupture of multiple faults. Back-projection source imaging indicates that the rupture occurred on distinct planes in an orthogonal conjugate fault system, with relatively slow rupture speed. The east-southeast-west-northwest ruptures add a new dimension to the seismotectonics of the Wharton Basin, which was previously thought to be controlled by north-south strike-slip faulting. The rupture turned twice into the compressive quadrant, against the preferred branching direction predicted by dynamic Coulomb stress calculations. Orthogonal faulting and compressional branching indicate that rupture was controlled by a pressure-insensitive strength of the deep oceanic lithosphere. PMID:22821986

Meng, L; Ampuero, J-P; Stock, J; Duputel, Z; Luo, Y; Tsai, V C

2012-08-10

101

Partonic Transverse Momentum Distributions  

Microsoft Academic Search

In recent years parton distributions have been generalized to account also for transverse degrees of freedom and new sets of more general distributions, Transverse Momentum Dependent (TMD) parton distributions and fragmentation functions were introduced. Different experiments worldwide (HERMES, COMPASS, CLAS, JLab-Hall A) have measurements of TMDs in semi-inclusive DIS processes as one of their main focuses of research. TMD studies

Patrizia Rossi; Patrizia

2010-01-01

102

TRANSVERSELY POLARIZED L PRODUCTION.  

SciTech Connect

Transversely polarized {Lambda} production in hard scattering processes is discussed in terms of a leading twist T-odd fragmentation function which describes the fragmentation of an unpolarized quark into a transversely polarized {Lambda}. We focus on the properties of this function and its relevance for the RHIC and HERMES experiments.

BORER,D.

2000-05-22

103

Barriers to faulting in the Basin-Range province: evidence from the Sou Hills transverse block  

SciTech Connect

Transverse structural blocks may inhibit the propagation of fault ruptures in the Basin-Range province. The Sou Hills, between Dixie and Pleasant Valleys, is a block of uplifted Tertiary bedrock transverse to the NNE-SSW trend of the central Nevada seismic belt. Three lines of evidence indicate that offset due to normal faulting is much less in the Sou Hills compared to adjacent segments of the seismic belt. First, estimates of total late Cenozoic offsets of pre-extension basalts show that the total offset is less in the Sou Hills. Second, analyses of landforms that reflect rates of relative uplift show that Quaternary tectonic activity on range-bounding faults declines where faults join the Sou Hills. Third, measurements of late Quaternary fault scarps show that individual rupture segments in the Sou Hills are shorter in length and have smaller displacements compared to the nearly continuous ruptures of several meters offset found along the Tobin and Stillwater Ranges to the north and south. The Sou Hills rupture pattern is distinctive: ruptures are dispersed over a wide zone rather than being concentrated along well-defined range fronts. Normal faulting patterns produced by the 1915 Pleasant Valley, Nevada and the 1983 Borah Peak, Idaho earthquakes indicate that a discontinuous, spatially dispersed faulting style typifies ruptures which die out in transverse bedrock features. These historic analogues support a model for prehistoric faulting in which ruptures have repeatedly died out in the Sou Hills. Transverse blocks such as the Sou Hills appear to present barriers to propagating ruptures.

Fonseca, J.E.

1985-01-01

104

Some characteristics of high strength fiber reinforced lightweight aggregate concrete  

Microsoft Academic Search

The effect of polypropylene and steel fibers on high strength lightweight aggregate concrete is investigated. Sintered fly ash aggregates were used in the lightweight concrete; the fines were partially replaced by fly ash. The effects on compressive strength, indirect tensile strength, modulus of rupture, modulus of elasticity, stress–strain relationship and compression toughness are reported. Compared to plain sintered fly ash

O Kayali; M. N Haque; B Zhu

2003-01-01

105

Creep and rupture of an ods alloy with high stress rupture ductility  

NASA Astrophysics Data System (ADS)

The creep and stress rupture properties of an oxide (Y2O3) dispersion strengthened nickel-base alloy, which also is strengthened by ?' precipitates, was studied at 760 °C and 1093 °C. At both temperatures the alloy YDNiCrAl exhibits unusually high stress rupture ductility as measured by both elongation and reduction in area. Failure was transgranular, and different modes of failure were observed including crystallographic fracture at intermediate temperatures and tearing or necking almost to a chisel point at higher temperatures. While the rupture ductility was high, the creep strength of the alloy was low relative to conventional ?' strengthened superalloys in the intermediate temperature range and to ODS alloys in the higher temperature range. These findings are discussed with respect to the alloy composition; the strengthening oxide phases, which are inhomogeneously dispersed; the grain morphology, which is coarse and elongated and exhibits many included grains; and the second phase inclusion particles occurring at grain boundaries and in the matrix. The creep properties, in particular the high stress dependencies and high creep activation energies measured, are discussed with respect to the resisting stress model of creep in particle strengthened alloys.

McAlarney, Mona E.; Arons, Richard M.; Howson, Tim E.; Tien, John K.; Baranow, Sanford

1982-08-01

106

Complex rupture during the 12 January 2010 Haiti earthquake  

USGS Publications Warehouse

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.

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.

2010-01-01

107

The ruptured PIP breast implant.  

PubMed

Public concern erupted about the safety of Poly Implant Prothèse (PIP) breast implants when it was revealed in 2011 that they contained an inferior, unlicensed industrial-grade silicone associated with a high rate of rupture. There followed national guidance for UK clinicians, which led to a considerable increase in referrals of asymptomatic women for breast implant assessment. In this review we discuss possible approaches to screening the PIP cohort and the salient characteristics of a ruptured implant. PMID:23622796

Helyar, V; Burke, C; McWilliams, S

2013-08-01

108

Creep-rupture tests of internally pressurized Inconel 702 tubes  

NASA Technical Reports Server (NTRS)

Seamless Inconel 702 tubes with 0.375-in. outside diameter and 0.025-in. wall thickness were tested to failure at temperatures from 1390 to 1575 F and internal helium pressures from 700 to 1800 psi. Lifetimes ranged from 29 to 1561 hr. The creep-rupture strength of the tubes was about 70 percent lower than that of sheet specimens. Larson-Miller correlations and photomicrographs of some specimens are presented.

Gumto, K. H.

1973-01-01

109

Fault Branching and Rupture Directivity  

NASA Astrophysics Data System (ADS)

Can the rupture directivity of past earthquakes be inferred from fault geometry? Nakata et al. [J. Geogr., 1998] propose to relate the observed surface branching of fault systems with directivity. Their work assumes that all branches are through acute angles in the direction of rupture propagation. However, in some observed cases rupture paths seem to branch through highly obtuse angles, as if to propagate ``backwards". Field examples of that are as follows: (1) Landers 1992. When crossing from the Johnson Valley to the Homestead Valley (HV) fault via the Kickapoo (Kp) fault, the rupture from Kp progressed not just forward onto the northern stretch of the HV fault, but also backwards, i.e., SSE along the HV [Sowers et al., 1994, Spotila and Sieh, 1995, Zachariasen and Sieh, 1995, Rockwell et al., 2000]. Measurements of surface slip along that backward branch, a prominent feature of 4 km length, show right-lateral slip, decreasing towards the SSE. (2) At a similar crossing from the HV to the Emerson (Em) fault, the rupture progressed backwards along different SSE splays of the Em fault [Zachariasen and Sieh, 1995]. (3). In crossing from the Em to Camp Rock (CR) fault, again, rupture went SSE on the CR fault. (4). Hector Mine 1999. The rupture originated on a buried fault without surface trace [Li et al., 2002; Hauksson et al., 2002] and progressed bilaterally south and north. In the south it met the Lavic Lake (LL) fault and progressed south on it, but also progressed backward, i.e. NNW, along the northern stretch of the LL fault. The angle between the buried fault and the northern LL fault is around -160o, and that NNW stretch extends around 15 km. The field examples with highly obtuse branch angles suggest that there may be no simple correlation between fault geometry and rupture directivity. We propose that an important distinction is whether those obtuse branches actually involved a rupture path which directly turned through the obtuse angle (while continuing also on the main fault), or rather involved arrest by a barrier on the original fault and jumping [Harris and Day, JGR, 1993] to a neighboring fault on which rupture propagated bilaterally to form what appears as a backward-branched structure. Our studies [Poliakov et al., JGR in press, 2002; Kame et al, EOS, 2002] of stress fields around a dynamically moving mode II crack tip show a clear tendency to branch from the straight path at high rupture speeds, but the stress fields never allow the rupture path to directly turn through highly obtuse angles, and hence that mechanism is unlikely. In contrast, study of fault maps in the vicinity of the Kp to HV fault transition [Sowers et al., 1994], discussed as case (1) above, strongly suggest that the large-angle branching occurred as a jump, which we propose as the likely general mechanism. Implications for the Nakata et al. [1998] aim of inferring rupture directivity from branch geometry is that this will be possible only when rather detailed characterization (by surface geology, seismic relocation, trapped waves) of fault connectivity can be carried out in the vicinity of the branching junction, to ascertain whether direct turning of the rupture path through an angle, or jumping and then propagating bilaterally, were involved in prior events. They have opposite implications for how we would associate past directivity with a (nominally) branched fault geometry.

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

2002-12-01

110

Creep rupture properties of 18 Pct Cr8 Pct Ni-Ti-Nb and Type 347H austenitic stainless steels  

Microsoft Academic Search

The relationship between the creep rupture strength and the precipitation behavior in Type 347H and TEMPALOY A-1 ® stainless\\u000a steels was studied. The rupture strength of Type 347H becomes much lower than that of TEMPALOY A-1 in the creep test of over\\u000a 10,000 hours at 700 ‡C. The reason is discussed in relation to the precipitation behavior during creep test.

Y. Minami; H. Kimura; M. Tanimura

1985-01-01

111

Creep-rupture properties of 2¹\\/â Cr1 Mo steel weldments with varying carbon content  

Microsoft Academic Search

The creep-rupture properties were determined on weld metal, transverse weldments, and normalized-and-tempered base metal for three heats of 2¹\\/â Cr-1 Mo steel with 0.003, 0.035, and 0.11 percent C at 454, 510, and 565 C (850, 950 and 1050 F). For a given temperature and carbon content, the creep-rupture properties of the weld metal were always greater than those of

R. J. Klueh; D. A. Canonico

1976-01-01

112

Percutaneous repair of acute ruptures of the tendo Achillis.  

PubMed

Minimally invasive repair of acute traumatic ruptures of the tendo Achillis may produce lower complications compared to open repair. Twenty-three active patients underwent percutaneous repair of an acute rupture of the tendo Achillis. Post-operatively, the ATRS score was administered to assess the functional status. The maximum calf circumference, isometric plantar flexion strength of the gastrocsoleus muscle complex, ankle dorsiflexion, and return to sport activity were assessed in all patients at an average post-operative follow-up of 25.7 months. At the last follow-up, the mean Achilles tendon total rupture score (ATRS) score was 84 (range: 53-99). Ankle dorsiflexion and maximum calf circumference on the operated limb were not significantly different compared to the uninjured side. The isometric strength on the operated limb was significantly lower (P=0.04) compared to the contralateral side. Of the 21 (90%) patients participating in sports activities, 16 (80%) had returned to their pre-operative sport, 2 changed to lower activity, and 1 increased his performance. This percutaneous technique provides satisfactory outcome in terms of strength and return to pre-operative level of sport activity. PMID:22341001

Guillo, Stephane; Del Buono, Angelo; Dias, Marion; Denaro, Vincenzo; Maffulli, Nicola

2013-02-01

113

Coupling a geodynamic seismic cycling model to rupture dynamic simulations  

NASA Astrophysics Data System (ADS)

The relevance and results of dynamic rupture scenarios are implicitly linked to the geometry and pre-existing stress and strength state on a fault. The absolute stresses stored along faults during interseismic periods, are largely unquantifiable. They are, however, pivotal in defining coseismic rupture styles, near-field ground motion, and macroscopic source properties (Gabriel et al., 2012). Obtaining these in a physically consistent manner requires seismic cycling models, which directly couple long-term deformation processes (over 1000 year periods), the self-consistent development of faults, and the resulting dynamic ruptures. One promising approach to study seismic cycling enables both the generation of spontaneous fault geometries and the development of thermo-mechanically consistent fault stresses. This seismo-thermo-mechanical model has been developed using a methodology similar to that employed to study long-term lithospheric deformation (van Dinther et al., 2013a,b, using I2ELVIS of Gerya and Yuen, 2007). We will innovatively include the absolute stress and strength values along physically consistent evolving non-finite fault zones (regions of strain accumulation) from the geodynamic model into dynamic rupture simulations as an initial condition. The dynamic rupture simulations will be performed using SeisSol, an arbitrary high-order derivative Discontinuous Galerkin (ADER-DG) scheme (Pelties et al., 2012). The dynamic rupture models are able to incorporate the large degree of fault geometry complexity arising in naturally evolving geodynamic models. We focus on subduction zone settings with and without a splay fault. Due to the novelty of the coupling, we first focus on methodological challenges, e.g. the synchronization of both methods regarding the nucleation of events, the localization of fault planes, and the incorporation of similar frictional constitutive relations. We then study the importance of physically consistent fault stress, strength, and geometry input for dynamic rupture propagation in terms of rupture path and dynamics. On the other hand, it will provide the opportunity to compare slow earthquake akin events developing in quasi-static geodynamic model to fully dynamic ruptures in terms of coseismic displacements and stress changes. Gabriel, A.-A. (2012), J.-P. Ampuero, L. A. Dalguer, and P. M. Mai, The transition of dynamic rupture modes in elastic media, J. Geophys. Res., 117(B9), 01480227. Gerya, T., and D. Yuen (2007), Robust characteristics method for modelling multiphase visco-elasto-plastic thermo-mechanical problems, Phys. Earth Planet In., 163(1-4), 83-105. Pelties, C. (2012), J. De la Puente, J.-P. Ampuero, G. B. Brietzke, and M. Käser Three-Dimensional Dynamic Rupture, Simulation with a High-order Discontinuous Galerkin Method on Unstructured Tetrahedral Meshes, J. Geophys. Res., 117(B2), B02309. van Dinther, Y. (2013a), T.V. Gerya, L.A. Dalguer, F. Corbi, F. Funiciello, and P.M. Mai, The seismic cycle at subduction thrusts: 2. Dynamic implications of geodynamic simulations validated with laboratory models, J. Geophys. Res., 118(4), 1502-1525. van Dinther, Y. (2013b), T.V. Gerya, L.A. Dalguer, P.M. Mai, G. Morra, and D. Giardini, The seismic cycle at subduction thrusts: insights from seismo-thermo-mechanical models, J. Geophys. Res., 118, 6183-6202.

Gabriel, Alice; van Dinther, Ylona

2014-05-01

114

Rupture of the flexor digitorum superficialis muscle belly during isometric weight training.  

PubMed

Isometric weight training is a well-recognised technique used by fitness trainers to increase muscle strength. We report a case of a flexor digitorum superficialis muscle belly rupture that occurred during this form of muscle training. Rupture of the belly of the forearm flexor muscles is rare. When the muscle undergoes tractional force in isometric weight training, there is a potential for it to rupture and result in the formation of a haematoma. This can lead to raised intracompartmental pressures which would require treatment with urgent fasciotomy. An awareness of this potential injury mechanism will help with early recognition and appropriate treatment. PMID:24177460

Chow, Whitney; Dickson, John; Khan, Umraz

2013-01-01

115

Failure of transversely stitched RTM lap joints  

Microsoft Academic Search

An experimental evaluation has been undertaken to investigate the effect of transverse stitching on the strength of composite single-lap joints. Balanced single-lap joints were considered, and the lay-up for the adherends was (0\\/ ±45\\/90)s. Specimens were stitched with Kevlar® thread in a zigzag pattern and were manufactured by using the resin-transfer moulding (RTM) technique. Experimental results indicated that stitched joints

L. Tong; L. K. Jain; K. H. Leong; D. Kelly; I. Herszberg

1998-01-01

116

Chronic Achilles tendon rupture reconstruction using a modified flexor hallucis longus transfer.  

PubMed

The purpose of this study was to report the management and outcome of 11 patients presenting with chronic Achilles tendon (AT) rupture treated by a modified flexor hallucis longus (FHL) transfer. Seven patients presented with a neglected AT rupture, one with a chronic AT rupture associated with Achilles tendinosis and three with an AT re-rupture. AT defect after fibrosis debridement averaged 7.4 cm. In addition to FHL transfer, we performed an augmentation using the two remaining fibrous scar stumps of the ruptured AT. Functional assessment was performed using the AOFAS score and isokinetic evaluation was performed to assess ankle plantarflexion torque deficit. Follow-up averaged 79 months. Functional outcome was excellent with a significant improvement of the AOFAS score at latest follow-up. No re-rupture nor major complication, particularly of wound healing, was observed. All patients presented with a loss of active range of motion of the hallux interphalangeal joint without functional weakness during athletic or daily life activities. Isokinetic testing at 30 degrees/second and 120 degrees/second revealed a significant average decrease of 28?±?11% and 36?±?4.1%, respectively, in plantarflexion peak torque. Although strength deficit persisted at latest follow-up, functional improvement was significant without morbidity due to FHL harvesting. For patients with chronic AT rupture with a rupture gap of at least 5 cm, surgical repair using FHL transfer with fibrous AT stump reinforcement achieved excellent outcomes. PMID:19697026

Wegrzyn, Julien; Luciani, Jean-François; Philippot, Rémi; Brunet-Guedj, Elisabeth; Moyen, Bernard; Besse, Jean-Luc

2010-12-01

117

Chronic Achilles tendon rupture reconstruction using a modified flexor hallucis longus transfer  

PubMed Central

The purpose of this study was to report the management and outcome of 11 patients presenting with chronic Achilles tendon (AT) rupture treated by a modified flexor hallucis longus (FHL) transfer. Seven patients presented with a neglected AT rupture, one with a chronic AT rupture associated with Achilles tendinosis and three with an AT re-rupture. AT defect after fibrosis debridement averaged 7.4 cm. In addition to FHL transfer, we performed an augmentation using the two remaining fibrous scar stumps of the ruptured AT. Functional assessment was performed using the AOFAS score and isokinetic evaluation was performed to assess ankle plantarflexion torque deficit. Follow-up averaged 79 months. Functional outcome was excellent with a significant improvement of the AOFAS score at latest follow-up. No re-rupture nor major complication, particularly of wound healing, was observed. All patients presented with a loss of active range of motion of the hallux interphalangeal joint without functional weakness during athletic or daily life activities. Isokinetic testing at 30 degrees/second and 120 degrees/second revealed a significant average decrease of 28?±?11% and 36?±?4.1%, respectively, in plantarflexion peak torque. Although strength deficit persisted at latest follow-up, functional improvement was significant without morbidity due to FHL harvesting. For patients with chronic AT rupture with a rupture gap of at least 5 cm, surgical repair using FHL transfer with fibrous AT stump reinforcement achieved excellent outcomes.

Luciani, Jean-Francois; Philippot, Remi; Brunet-Guedj, Elisabeth; Moyen, Bernard; Besse, Jean-Luc

2009-01-01

118

INVESTIGATIONS ON THE TIME-RUPTURE BEHAVIOR OF ALUMINUM-MAGNESIUM ALLOYS  

Microsoft Academic Search

The high-strength alloy Al- Zn-Mg-Cu 0.5 is insensitive to continued ; loading at room temperature. At 100 and 150 deg C however a distinct drop of the ; time-rupture strength occurs which is characteristic also for other high-strength ; aluminum alloys. This drop may be connected to overaging phenomena. The ; results, according to E. J. Dorn, could approximately be

Mann

1961-01-01

119

Transverse structure of the nucleon  

Microsoft Academic Search

In recent years parton distributions, describing longitudinal momentum, helicity and transversity distributions of quarks and gluons, have been generalized to account also for transverse degrees of freedom. Two new sets of more general distributions, Transverse Momentum Distributions (TMDs) and Generalized Parton Distributions (GPDs) were introduced to describe transverse momentum and space distributions of partons. Great progress has been made since

Harut Avakian

2010-01-01

120

Spontaneous Rupture of the Esophagus  

PubMed Central

Spontaneous rupture of the esophagus remains a medical and surgical challenge. Its diagnosis is often missed or delayed resulting in increased morbidity and mortality, and controversy exists as to the mode of therapy for the cases seen later than 12 hours after rupture. During the last seven years, nine patients were treated at Grady Memorial Hospital. Four patients, “early group,” were operated upon within 12 hours from the onset of their symptoms and five, “late group,” were operated upon between 20-76 hours (average 41) after rupture. All four patients in the “early group” had primary repair of the rupture and two had, in addition, fundoplication. From the two patients with primary repair alone, one developed postoperative leakage at the esophageal suture line, which closed spontaneously; whereas, in the two patients with fundoplication, no leakage occurred. Three of the four patients recovered and one died from renal failure, gastrointestinal bleeding, and gastric perforation. In the “late group” one patient had T-tube drainage of the esophagus and died. Two had primary repair alone with one death and the other two had primary repair with fundoplication 20 and 76 hours postrupture and both recovered. The two deaths in the “late group” were due to leakage at the site of the rupture. This study suggests that even in patients diagnosed late as having rupture of the esophagus, primary repair can be implemented with reasonable success. Good mediastinal, pleural and gastric drainage, high levels of appropriate antibiotics, and provision of good nourishment are of paramount importance for the successful management of these desperately ill patients. ImagesFig. 2A.FIG. 2B.FIG. 2C.Fig. 2D.

Symbas, Panagiotis N.; Hatcher, Charles R.; Harlaftis, Nickolaos

1978-01-01

121

Delayed tracheal rupture following thyroidectomy.  

PubMed

Thyroidectomy is a commonly performed, low-risk procedure. Tracheal perforation during thyroidectomy is rare, and delayed rupture of the trachea rarer still. We present the case of a patient who underwent total thyroidectomy secondary to Grave's disease who, on postoperative day 7, developed massive subcutaneous emphysema and respiratory distress. Surgical exploration revealed a rupture of the anterolateral tracheal wall at the level of the first tracheal ring. The defect was repaired primarily and the patient recovered uneventfully. The risk factors for and the management of this rare complication are discussed. PMID:18487029

Damrose, Edward J; Damrose, John F

2009-02-01

122

Strength enhancement process for prealloyed powder superalloys  

NASA Technical Reports Server (NTRS)

A technique involving superplastic processing and high-pressure autoclaving was applied to a nickel-base prealloyed powder alloy. Tensile strengths as high as 2865 MN/sq m (415 ksi) at 480 C (900 F) were obtained with as-superplastically deformed material. Appropriate treatments yielding materials with high-temperature tensile and stress-rupture strengths (980 C (1800 F)) were also devised.

Waters, W. J.; Freche, J. C.

1977-01-01

123

Noninterceptive transverse beam diagnostics  

SciTech Connect

The transverse emittance properties of a high-current linear accelerator may be measured by using TV cameras sensitive to the visible radiation emitted following beam interactions with residual gas. This paper describes the TV system being used to measure emittances for the Fusion Materials Irradiation Test (FMIT) project.

Chamberlin, D.D.; Minerbo, G.N.; Teel, L.E. Jr.; Gilpatrick, J.D.

1981-01-01

124

Quadriceps Tendon Rupture due to Postepileptic Convulsion  

PubMed Central

We present a case of quadriceps tendon (QT) rupture. QT ruptures can occur in all ages. The cause is mostly traumatic in origin. Spontaneous ruptures that are thought to result from predisposing conditions are rare. Post-convulsion QT ruptures lacking traumas in their history can be overlooked in clinical examinations. This should be born in mind by the attending physician, as early diagnosis and treatment of the condition can lead to satisfactory outcomes.

Erkut, Adem; Guvercin, Yilmaz; Sahin, Rifat; Keskin, Davut

2014-01-01

125

Dynamic Rupture Segmentation Along The Nankai Trough, Southwest Japan  

NASA Astrophysics Data System (ADS)

In southwest Japan, large devastating earthquakes (Mw>8) occurred along the Nankai subduction zone every 100-200 years (e.g. Ando, 1975, Tectonophys.; Ishibashi, 2004, Ann. Geophys.). Historical records revealed the segmented nature of the 600 km long seismogenic zone, producing Nankai and Tonankai earthquakes to occur separately or jointly at each cycle. The intersegment zone which separates Nankai and Tonankai source areas, near the Kii Peninsula, should have some special physical properties. In this study, we investigate the dynamic linkage of the coseismic slips on the Nankai and Tonankai segments, by modeling the spontaneous rupture propagation on the subduction interface. To conduct a reliable modeling, the parameters’ lateral variations along the place interface are introduced by combining several geophysical observation data sets. First, we use a large-scale 3D geometry for the plate interface, inferred from seismicity; we also integrate the slip deficit distribution (Hashimoto et al., 2009, SSJ meeting) obtained by inversion of GPS data, to constrain the distribution of stress drop on the interface. This distribution is not uniform, and explains the 1st order asperities of the subduction zone: Hyuga, Nankai, Tonankai and Tokai areas appear clearly as loaded regions. In addition, a constitutive friction law is required to link fault slip and stress release. We compiled regional geophysical information relevant to the segmentation, to infer the distribution of the frictional parameters at seismogenic depths. We focused on areas where the rupture is known to have stopped. The barriers seem to be related to upper plate structure (Wells et al. 2003, JGR, Rosenau and Oncken 2009, JGR). Uplifted areas show common characteristics: end of seismogenic segments, underplating in the wedge, and higher density of the upper old wedge (granitic intrusions). Following above review, we introduced 3 barrier regions delimiting 2 asperity regions (Nankai and Tonankai). Inside the barrier, the fracture energy changes in regional scale, via a change of the critical slip distance scaling. The strength remains uniform along the interface. Asperities are produced by the initial stress distribution inferred from slip deficit. Using this model setting, we computed a few different spontaneous rupture scenarios, by changing only the location of rupture initiation. Remarkably, we could reproduce the segmentation of the rupture, as observed during the 1940’s sequence, provided that the rupture initiates close to the Kii peninsula barrier area. However, if the rupture initiate far from the Kii peninsula, close to Tokai or west of Muroto cape for instance, the rupture is more likely to break the full plate interface in a single rupture event, consistently with what has been observed in the past. The rupture segmentation appears to be a consequence of the friction properties off-Kii Peninsula, as well as the rupture initiation position. This work provides a reliable way to enlighten the conditional segmentation process, as a consequence of the earthquake dynamic rupture.

Hok, S.; Fukuyama, E.; Hashimoto, C.

2010-12-01

126

Spontaneous Splenic Rupture in Melanoma  

PubMed Central

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.

Oryan, Ahmad; Davari, Aida; Daneshbod, Khosrow; Daneshbod, Yahya

2014-01-01

127

Spontaneous rupture of a varicocoele.  

PubMed

We present the case of a young male with an acute scrotal haematoma due to spontaneous rupture of a spermatic cord varicocoele confirmed by Doppler ultrasonography. After failure of conservative management, surgical exploration was performed with successful evacuation of the scrotal haematoma. PMID:20441071

Chin, W N; Cadogan, M; Wan, R; Harrison, L

2009-11-01

128

46 CFR 64.61 - Rupture disc.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Rupture disc. 64.61 Section 64.61 Shipping COAST...Vacuum Relief Devices for MPTs § 64.61 Rupture disc. If a rupture disc is the only pressure relief device on the tank,...

2013-10-01

129

Conservative treatment for postintubation tracheobronchial rupture  

Microsoft Academic Search

Background. Postintubation tracheobronchial rupture is usually responsible for unstable intraoperative or postoperative conditions, and its management is discussed. We insist on conservative treatment as a viable alternative after late diagnosis of postintubation tracheobronchial rupture.Methods. We conducted a retrospective study including 14 consecutive patients treated between April 1981 and July 1998.Results. Twelve tracheobronchial ruptures occurred after intubation for general surgery and

Jacques Jougon; Michel Ballester; Emmanuel Choukroun; Jean Dubrez; Gilles Reboul; Jean-François Velly

2000-01-01

130

Rupture of the pectoralis major muscle: surgical treatment in athletes.  

PubMed

Pectoralis major tendon rupture is a relatively rare injury, resulting from violent, eccentric contraction of the muscle. Over 50% of these injuries occur in athletes, classically in weight-lifters during the 'bench press' manoeuvre. We present 13 cases of distal rupture of the pectoralis major muscle in athletes. All patients underwent open surgical repair. Magnetic resonance imaging was used to confirm the diagnosis in all patients. The results were analysed using (1) the visual analogue pain score, (2) functional shoulder evaluation and (3) isokinetic strength measurements. At the final follow-up of 23.6 months (14-34 months), the results were excellent in six patients, good in six and one had a poor result. Eleven patients were able to return to their pre-injury level of sports. The mean time for a return to sports was 8.5 months. The intraoperative findings correlated perfectly with the reported MRI scans in 11 patients and with minor differences in 2 patients. We wish to emphasise the importance of accurate clinical diagnosis, appropriate investigations, early surgical repair and an accelerated rehabilitation protocol for the distal rupture of the pectoralis major muscle as this allows complete functional recovery and restoration of full strength of the muscle, which is essential for the active athlete. PMID:16847645

Kakwani, R G; Matthews, J J; Kumar, K M; Pimpalnerkar, A; Mohtadi, N

2007-04-01

131

The tensile strength and ductility of continuous fibre composites  

Microsoft Academic Search

The plastic instability approach has been applied to the tensile behaviour of a continuous fibre composite. It is shown that the combination of two components with different strengths and degrees of work-hardening produces a new material with a new degree of work-hardening, which may be determined by the present analysis. Expressions for the elongation at rupture and the strength of

S. T. Mileiko

1969-01-01

132

Partonic Transverse Momentum Distributions  

SciTech Connect

In recent years parton distributions have been generalized to account also for transverse degrees of freedom and new sets of more general distributions, Transverse Momentum Dependent (TMD) parton distributions and fragmentation functions were introduced. Different experiments worldwide (HERMES, COMPASS, CLAS, JLab-Hall A) have measurements of TMDs in semi-inclusive DIS processes as one of their main focuses of research. TMD studies are also an important part of the present and future Drell-Yan experiments at RICH and JPARC and GSI, respectively, Studies of TMDs are also one of the main driving forces of the Jefferson Lab (JLab) 12 GeV upgrade project. Progress in phenomenology and theory is flourishing as well. In this talk an overview of the latest developments in studies of TMDs will be given and newly released results, ongoing activities, as well as planned near term and future measurements will be discussed.

Rossi, Patrizia [Laboratori Nazionali di Frascati-INFN, Via E. Fermi 40, 00044 Frascati (Italy)

2010-08-04

133

Partonic Transverse Momentum Distributions  

NASA Astrophysics Data System (ADS)

In recent years parton distributions have been generalized to account also for transverse degrees of freedom and new sets of more general distributions, Transverse Momentum Dependent (TMD) parton distributions and fragmentation functions were introduced. Different experiments worldwide (HERMES, COMPASS, CLAS, JLab-Hall A) have measurements of TMDs in semi-inclusive DIS processes as one of their main focuses of research. TMD studies are also an important part of the present and future Drell-Yan experiments at RICH and JPARC and GSI, respectively, Studies of TMDs are also one of the main driving forces of the Jefferson Lab (JLab) 12 GeV upgrade project. Progress in phenomenology and theory is flourishing as well. In this talk an overview of the latest developments in studies of TMDs will be given and newly released results, ongoing activities, as well as planned near term and future measurements will be discussed.

Rossi, Patrizia

2010-08-01

134

[Ettore Majoran's transversal epistemology].  

PubMed

« Il valore delle leggi statistiche nella fisica e nelle scienze sociali » is Ettore Majorana's only work on science. It offers a critique of classical determinism, establishing an analogy between the laws of quantum mechanics and social science and arguing that both are intrinsically linked to probability. This article first studies this argument from the standpoing of metaphysics, physics, and sociology, and then assesses the significance of this transversal epistemology. PMID:23636783

Bontems, Vincent

2013-01-01

135

Transverse Structure of Hadrons  

SciTech Connect

Parton distributions in impact parameter space, which are obtained by Fourier transforming GPDs, exhibit a significant deviation from axial symmetry when the target and/or quark are transversely polarized. Connections between this deformation and single-spin asymmetries as well as with quark-gluon correlations are discussed. The information content of the DVCS amplitude at fixed Q2 can be condensed into GPDs along the 'diagonal' x = ? plus D-form factor.

Matthias Burkardt

2011-05-01

136

Thrust-type subduction-zone earthquakes and seamount asperites: A physical model for seismic rupture  

SciTech Connect

A thrust-type subduction-zone earthquake of M{sub W} 7.6 ruptures an area of {approximately}6,000 km{sup 2}, has a seismic slip of {approximately}1 m, and is nucleated by the rupture of an asperity {approximately}25km across. A model for thrust-type subduction-zone seismicity is proposed in which basaltic seamounts jammed against the base of the overriding plate act as strong asperities that rupture by stick-slip faulting. A M{sub W} 7.6 event would correspond to the near-basal rupture of a {approximately}2-km-tall seamount. The base of the seamount is surrounded by a low shear-strength layer composed of subducting sediment that also deforms between seismic events by distributed strain (viscous flow). Planar faults form in this layer as the seismic rupture propagates out of the seamount at speeds of kilometers per second. The faults in the shear zone are disrupted after the event by aseismic, slow viscous flow of the subducting sediment layer. Consequently, the extent of fault rupture varies for different earthquakes nucleated at the same seamount asperity because new fault surfaces form in the surrounding subducting sediment layer during each fast seismic rupture.

Cloos, M. (Univ. of Texas, Austin (United States))

1992-07-01

137

Spontaneous perforation of solitary ulcer of transverse colon.  

PubMed

Spontaneous ruptures of the colon and rectum are extremely uncommon clinical entities and always require laparotomy. A 44-year-old female was admitted with a 12-hour history of severe abdominal pain periumbilically and at the right hypochondrium. The patient was immediately transferred to the department of surgery for close surgical observation. Computed tomography (CT) of the entire abdomen performed just before the operation demonstrated thickening of the wall of the ascending colon with pericolic fat stranding. Surgery revealed a perforation at the antimesenteric wall of the transverse colon and segmental colectomy of the transverse colon was performed. The histological evaluation demonstrated a perforated solitary ulcer of the transverse colon. There are only few known etiologic factors concerning spontaneous ruptures of the colon and rectum and usually none of these causative factors can easily be recognised. Their clinical appearance is most of the times acute abdomen and, despite the use of all appropriate diagnostic methods, the diagnosis is usually set postoperatively. PMID:20090246

Galanis, Ioannis; Dragoumis, Dimitrios; Kalogirou, Thomas; Lakis, Sotiris; Kotakidou, Rodi; Atmatzidis, Konstantinos

2010-01-01

138

Delayed diagnosis of traumatic diaphragmatic rupture with herniation of the liver: a case report.  

PubMed

Diaphragmatic rupture is a potentially life-threatening clinical situation. It occurs as a result of high-velocity blunt or penetrating injury to the abdomen and thorax. Acute traumatic rupture of the diaphragm may go undetected, and there is often a delay between the injury and diagnosis. Right-sided rupture is less common due to hepatic protection and increased strength of the right hemidiaphragm. We report the case of a 28-year-old man who was admitted with breathlessness to our hospital, 72 hours after trauma. Since clinical signs and symptoms were nonspecific, helical computed tomography was done, which revealed diaphragmatic rupture with hepatothorax. Emergency thoracotomy was done to repair diaphragmatic rent. The postoperative period was uneventful, and the patient was discharged three weeks later. PMID:22792826

Kuppusamy, Anand; Ramanathan, Gayathri; Gurusamy, Jayakar; Ramamoorthy, Balaji; Parasakthi, Karunanithi

2012-03-01

139

The strength of transverse waves in marginal planar detonation waves  

Microsoft Academic Search

The structure of planar detonation waves propagating in a narrow rectangular channel, of cross section 3×¼ in2, has been studied for a mixture of stoichiometric oxyhydrogen diluted with 60% argon. It is confirmed that at an initial pressure of 80 torr the waves generated are self-sustaining and possess either two or three Mach interactions along the broad wall of the

D H Edwards; R J Meddins

1971-01-01

140

Transverse motion of fragmenting faint meteors observed with the Canadian Automated Meteor Observatory  

NASA Astrophysics Data System (ADS)

Nine fragmenting, faint meteors (peak magnitude ?+1, mass <10-4 kg) were observed with the Canadian Automated Meteor Observatory (CAMO). Fragments for eight of the nine meteors exhibited significant transverse motion, perpendicular to the meteor velocity. Transverse speeds of the order 100 m s were observed, while models of aerodynamic loading predict speeds of the order 0.5 m s. Acceleration of the fragments in the transverse direction was negligible. Alternate methods of fragmentation, namely rotation and electrostatic charge accumulation, were examined through basic models to explain the observed transverse speeds. Meteoroid strengths of the order 106 Pa were derived, matching observed strengths of larger, brighter meteors.

Stokan, E.; Campbell-Brown, M. D.

2014-04-01

141

Strength Testing.  

ERIC Educational Resources Information Center

Postural deviations resulting from strength and flexibility imbalances include swayback, scoliosis, and rounded shoulders. Screening tests are one method for identifying strength problems. Tests for the evaluation of postural problems are described, and exercises are presented for the strengthening of muscles. (JN)

Londeree, Ben R.

1981-01-01

142

Traumatic rupture of horseshoe kidney.  

PubMed

We present the case of a 25-year-old male who came to the emergency room for pain and abdominal distension following trauma to the mesogastrium. A CT scan was performed, revealing a voluminous retroperitoneal hematoma with laceration of both inferior renal poles with regard to rupture of the isthmus of a horseshoe kidney. The patient presented anemization and increased pain, requiring selective embolization by means of arteriography of a branch of the right renal artery and placement of a double J stent due to urinary extravasation in the lower left kidney pole. Following 1 year of monitoring, the patient has maintained normal renal function. Renal affection in blunt abdominal trauma is frequent, occurring in 7% of previously pathological kidneys. The traumatic rupture of horseshoe kidney is facilitated by its particular anatomical characteristics, constituting an infrequent entity, knowledge of which is necessary to achieve conservative management that renders it possible to preserve renal function. PMID:21934278

Molina Escudero, R; Cancho Gil, M J; Husillos Alonso, A; Lledó García, E; Herranz Amo, F; Ogaya Piniés, G; Ramón Botella, E; Simó, G; Navas Martínez, M C; Hernández Fernández, C

2012-01-01

143

Uterine rupture in a primigravida with adenomyosis recently subjected to laparoscopic resection of rectovaginal endometriosis: case report.  

PubMed

A case of intrapartum, complete, low-posterior wall, transverse uterine rupture, complicated by uterine atony and treated by emergency hysterectomy in a primigravida with uterine adenomyosis who delivered vaginally at 37 weeks plus 5 days of gestation, 9 months after undergoing laparoscopic resection of rectovaginal septum endometriosis. PMID:18439512

Villa, Gioia; Mabrouk, Mohamed; Guerrini, Manuela; Mignemi, Giuseppe; Colleoni, Giulio Gandolfi; Venturoli, Stefano; Seracchioli, Renato

2008-01-01

144

Uterine Rupture in a Primigravida with Adenomyosis Recently Subjected to Laparoscopic Resection of Rectovaginal Endometriosis: Case Report  

Microsoft Academic Search

A case of intrapartum, complete, low-posterior wall, transverse uterine rupture, complicated by uterine atony and treated by emergency hysterectomy in a primigravida with uterine adenomyosis who delivered vaginally at 37 weeks plus 5 days of gestation, 9 months after undergoing laparoscopic resection of rectovaginal septum endometriosis.

Gioia Villa; Mohamed Mabrouk; Manuela Guerrini; Giuseppe Mignemi; Giulio Gandolfi Colleoni; Stefano Venturoli; Renato Seracchioli

2008-01-01

145

Effect of normalization temperature on the creep strength of modified 9Cr1Mo steel  

Microsoft Academic Search

The effect of normalization temperature from 850 C to 1050 C on the structure and creep-rupture properties of modified 9Cr-1Mo\\u000a steel was studied. Normalization at temperatures below 925 C resulted in structures containing significant polygonized, recovered\\u000a ferrite. The ferrite structures had poor creep-rupture strength: roughly two orders of magnitude increase in minimum creep\\u000a rate or decrease in rupture life for

T. C. Totemeier; H. Tian; J. A. Simpson

2006-01-01

146

Splenic rupture following endoscopic polypectomy.  

PubMed

A 70-year-old man presented with two medium-sized colon polyps at the office of a gastroenterologist. After endoscopic polypectomy in a hospital, the patient was admitted to another hospital because of collapse and increasing abdominal pain. CT scan revealed hematoperitoneum and splenic subcapsular hematoma. Laparotomy with splenectomy was performed because of extended splenic rupture. The postoperative course was unremarkable except late wound dehiscence. PMID:20352593

Wiedmann, M W; Kater, F; Böhm, B

2010-04-01

147

Achilles tendon rupture in badminton.  

PubMed Central

The typical badminton player with an Achilles tendon rupture is 36 years old and, despite limbering up, is injured at the rear line in a sudden forward movement. He resumes work within three months and has a slight lack of dorsiflexion in the ankle as the main complication. Most patients resume badminton within one year, but some finish their sports career, mainly due to fear of a new injury. The investigation discusses predisposing factors and prophylactic measures.

Kaalund, S; Lass, P; H?gsaa, B; N?hr, M

1989-01-01

148

Molecular dynamics of interface rupture  

NASA Technical Reports Server (NTRS)

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.

Koplik, Joel; Banavar, Jayanth R.

1993-01-01

149

CT of blunt diaphragmatic rupture.  

PubMed

The diagnosis of blunt diaphragmatic rupture (BDR) is difficult and often missed, leaving many patients with this traumatic injury at risk for life-threatening complications. The potential diagnostic pitfalls are numerous and include anatomic variants and congenital and acquired abnormalities. Chest radiography, despite its known limitations, may still be helpful in the early assessment of severe thoracoabdominal trauma and for detecting initially overlooked BDR or late complications of BDR. However, since the development of helical and multidetector scanners, computed tomography (CT) has become the reference standard; thus, knowledge of the CT signs suggestive of BDR is important for recognition of this injury pattern. A large number of CT signs of BDR have been described elsewhere, many of them individually, but the use of various appellations for the same sign can make previously published reports confusing. The systematic description and classification of CT signs provided in this article may help clarify matters and provide clues for diagnosing BDR. The authors describe 19 distinct CT signs grouped in three categories: direct signs of rupture, indirect signs that are consequences of rupture, and signs that are of uncertain origin. Since no single CT sign can be considered a marker leading to a correct diagnosis in every case of BDR, accurate diagnosis depends on the analysis of all signs present. PMID:22411944

Desir, Amandine; Ghaye, Benoît

2012-01-01

150

Method and apparatus for determining tensile strength  

DOEpatents

A method and apparatus is described for determining the statistical distribution of apparent tensile strength of rock, the size effect with respect to tensile strength, as well as apparent deformation modulus of both intact and fractured or jointed rock. The method is carried out by inserting a plug of deformable material, such as rubber, in an opening of a specimen to be tested. The deformable material is loaded by an upper and lower platen until the specimen ruptures, whereafter the tensile strength is calculated based on the parameters of the test specimen and apparatus.

Ratigan, J.L.

1982-05-28

151

Method and apparatus for determining tensile strength  

DOEpatents

A method and apparatus for determining the statistical distribution of apparent tensile strength of rock, the size effect with respect to tensile strength, as well as apparent deformation modulus of both intact and fractured or jointed rock. The method is carried out by inserting a plug of deformable material, such as rubber, in an opening of a specimen to be tested. The deformable material is loaded by an upper and lower platen until the specimen ruptures, whereafter the tensile strength is calculated based on the parameters of the test specimen and apparatus.

Ratigan, Joe L. (Rapid City, SD)

1984-01-01

152

Neutron Transversity at Jefferson Lab  

SciTech Connect

Nucleon transversity and single transverse spin asymmetries have been the recent focus of large efforts by both theorists and experimentalists. On-going and planned experiments from HERMES, COMPASS and RHIC are mostly on the proton or the deuteron. Presented here is a planned measurement of the neutron transversity and single target spin asymmetries at Jefferson Lab in Hall A using a transversely polarized {sup 3}He target. Also presented are the results and plans of other neutron transverse spin experiments at Jefferson Lab. Finally, the factorization for semi-inclusive DIS studies at Jefferson Lab is discussed.

Jian-Ping Chen; Xiaodong Jiang; Jen-chieh Peng; Lingyan Zhu

2005-09-07

153

Transverse junction stripe laser  

SciTech Connect

This patent describes a semiconductor laser the structure, comprising in combination: a substrate including first and second surface sections having different crystallographic orientation, a semiconductor laser formed on the substrate and including an active layer extending laterally over the first and second surface sections and having a p-n junction therein extending in a direction substantially transverse to the surface of the active layer, radiation being produced by the presence of an electrical current across the transaverse p-n junction of a magnitude above a threshold value for lasing, the active layer being amphoterically doped to produce by crystal plane dependent doping a first n-type region therein where the active layer is adjacent to the first surface section of the substrate and a second p- type region where the active layer is adjacent the second surface region of the substrate, and electrical means for producing an electrical current across the transverse p-n junction of a magnitude greater than the threshold value to produce lasing radiation in the active layer.

Harder, C.S.; Jaekel, H.; Meier, H.P.

1989-02-14

154

Probabilistic simulation of uncertainties in composite uniaxial strengths  

NASA Technical Reports Server (NTRS)

Probabilistic composite micromechanics methods are developed that simulate uncertainties in unidirectional fiber composite strengths. These methods are in the form of computational procedures using composite mechanics with Monte Carlo simulation. The variables for which uncertainties are accounted include constituent strengths and their respective scatter. A graphite/epoxy unidirectional composite (ply) is studied to illustrate the procedure and its effectiveness to formally estimate the probable scatter in the composite uniaxial strengths. The results show that ply longitudinal tensile and compressive, transverse compressive and intralaminar shear strengths are not sensitive to single fiber anomalies (breaks, intergacial disbonds, matrix microcracks); however, the ply transverse tensile strength is.

Chamis, C. C.; Stock, T. A.

1990-01-01

155

Dynamic stress drop and rupture dynamics of the October 15, 1979 Imperial Valley, California, earthquake  

NASA Astrophysics Data System (ADS)

A dynamic faulting model is constructed to determine the dynamic stress drop and relative strength distribution for the October 15, 1989 Imperial Valley earthquake, and to study the dynamics of rupture propagation for this event. Reproduction of the kinematic quantities of the strike-slip rate, strike-slip final offset, rupture time, and rupture duration, bu varying the dynamic parameters of dynamic stress drop and yield strength, is attempted. The fault plane is discretized in 1.5 km square grids. The model incorporates first-order corrections for the effect of the free surface and material property heterogeneity on the calculation of rupture at depth. The strike-slip particle velocities, final offsets, and rupture durations of the kinematic model are matched within about 40% everywhere below about 5 km, except in the hypocentral region and in a high displacement region 20 km north of the epicenter. The strike-slip rate of the dynamic model is half and rupture duration double those of the kinematic model in the epicentral region. The rupture durations and strike-slip final offsets are two thirds those of the kinematic model in a high-stress drop region beneath the El Centro crossing array. Two slip concentrations correspond to stress drop concentrations, one of about 80 bar at 20 km from the epicenter and at 8 km depth, and the other of about 70 bar at 30 km from the epicenter and 10 km depth. Most of the dynamic stress drop occurs between the depths of 9 and 11 km, averaging about 60 bar. Stress drops in the 7-9 km range vary between 25 and 35 bar, while stress drops in the 5-7 km depth range vary between 10 and 15 bar. This depth dependence of stress drop was a consistent feature across nearly 20 km of the fault. Stress drop appeared to be well correlated with rock type; negative stress drop was found in the sediment regions and the regions at depth, while positive stress drop was found in the metasediment regions between the depths of 5 and 11 km. Yield strength and rupture velocity are inversely related; high yield strength is found in regions of low rupture velocity and vice versa. Rupture was found to terminate at the northern end of the fault by collision with a high strength barrier. A region of supersonic rupture velocity was found to occur in a region of high stress drop and low fracture strength. The kinematic rupture velocity at the northern end of the fault was found to be unreasonably low; results show that this region reaches its peak stress before the kinematic break time. Yield strength increased with depth in the seismogenetic zone until the base of the zone was reached, below which it tapered off slightly

Quin, H.

1990-03-01

156

Nondestructive Evaluation and Monitoring Results from COPV Accelerated Stress Rupture Testing, NASA White Sands Test Facility (WSTF)  

NASA Technical Reports Server (NTRS)

Develop and demonstrate NDE techniques for real-time characterization of CPVs and, where possible, identification of NDE capable of assessing stress rupture related strength degradation and/or making vessel life predictions (structural health monitoring or periodic inspection modes). Secondary: Provide the COPV user and materials community with quality carbon/epoxy (C/Ep) COPV stress rupture progression rate data. Aid in modeling, manufacturing, and application of COPVs for NASA spacecraft.

Saulsberry Regor

2010-01-01

157

Intestinal adhesion due to previous uterine surgery as a risk factor for delayed diagnosis of uterine rupture: a case report  

PubMed Central

Introduction Uterine rupture is a life-threatening condition both to mothers and fetuses. Its early diagnosis and treatment may save their lives. Previous myomectomy is a high risk factor for uterine rupture. Intestinal adhesion due to previous myomectomy may also prevent early diagnosis of uterine rupture. Case presentation A 38-year-old primiparous non-laboring Japanese woman with a history of myomectomy was admitted in her 34th week due to lower abdominal pain. Although the pain was slight and her vital signs were stable, computed tomography revealed massive fluid collection in her abdominal cavity, which led us to perform a laparotomy. Uterine rupture had occurred at the site of the previous myomectomy; however, the small intestine was adhered tightly to the rupture, thus masking it. The baby was delivered through a low uterine segment transverse incision. The ruptured uterine wall was reconstructed. Conclusion Intestinal adhesion due to a prior myomectomy occluded a uterine rupture, possibly masking its symptoms and signs, which may have prevented early diagnosis.

2011-01-01

158

Spontaneous Rupture of a Functioning Adrenocortical Carcinoma  

PubMed Central

Adrenocortical carcinoma (ACC) is a rare malignancy with poor prognosis, and it can be classified as either a functional or nonfunctional tumor. Affected patients usually present with abdominal pain or with symptoms related to the mass effect or hormonal activity of the tumor. Several cases of spontaneously ruptured nonfunctional adrenocortical carcinoma have been reported, but no case of a spontaneous rupture of functioning adrenocortical carcinoma has been described. We report a functioning adrenocortical carcinoma that spontaneously ruptured during a work-up.

Chung, Jin Ook; Cho, Dong Hyeok; Lee, Jae Hyuk; Kwon, Dong Deuk; Chung, Dong Jin

2010-01-01

159

Multidisciplinary management of ruptured hepatocellular carcinoma  

Microsoft Academic Search

Spontaneous rupture of hepatocellular carcinoma (HCC) is a dramatic presentation of the disease. Most published studies are\\u000a from Asian centers, and North American experience is limited. This study was under-taken to review the experience of ruptured\\u000a HCC at a North American multidisciplinary unit. Thirty pa-tients presenting with ruptured HCC at a tertiary care center from\\u000a 1985 to 2004 were studied

Andrzej K. Buczkowski; Peter T. W. Kim; Stephen G. Ho; David F. Schaeffer; Sung I. Lee; David A. Owen; Alan H. Weiss; Stephen W. Chung; Charles H. Scudamore

2006-01-01

160

A model of growth and rupture of abdominal aortic aneurysm.  

PubMed

We present here a coupled mathematical model of growth and failure of the abdominal aortic aneurysm (AAA). The failure portion of the model is based on the constitutive theory of softening hyperelasticity where the classical hyperelastic law is enhanced with a new constant indicating the maximum energy that an infinitesimal material volume can accumulate without failure. The new constant controls material failure and it can be interpreted as the average energy of molecular bonds from the microstructural standpoint. The constitutive model is compared to the data from uniaxial tension tests providing an excellent fit to the experiment. The AAA failure model is coupled with a phenomenological theory of soft tissue growth. The unified theory includes both momentum and mass balance laws coupled with the help of the constitutive equations. The microstructural alterations in the production of elastin and remodeling of collagen are reflected in the changing macroscopic parameters characterizing tissue stiffness, strength and density. The coupled theory is used to simulate growth and rupture of an idealized spherical AAA. The results of the simulation showing possible AAA ruptures in growth are reasonable qualitatively while the quantitative calibration of the model will require further clinical observations and in vitro tests. The presented model is the first where growth and rupture are coupled. PMID:18255074

Volokh, K Y; Vorp, D A

2008-01-01

161

Material Parameters for Creep Rupture of Austenitic Stainless Steel Foils  

NASA Astrophysics Data System (ADS)

Creep rupture properties of austenitic stainless steel foil, 347SS, used in compact recuperators have been evaluated at 700 °C in the stress range of 54-221 MPa to establish the baseline behavior for its extended use. Creep curves of the foil show that the primary creep stage is brief and creep life is dominated by tertiary creep deformation with rupture lives in the range of 10-2000 h. Results are compared with properties of bulk specimens tested at 98 and 162 MPa. Thin foil 347SS specimens were found to have higher creep rates and higher rupture ductility than their bulk specimen counterparts. Power law relationship was obtained between the minimum creep rate and the applied stress with stress exponent value, n = 5.7. The value of the stress exponent is indicative of the rate-controlling deformation mechanism associated with dislocation creep. Nucleation of voids mainly occurred at second-phase particles (chromium-rich M23C6 carbides) that are present in the metal matrix by decohesion of the particle-matrix interface. The improvement in strength is attributed to the precipitation of fine niobium carbides in the matrix that act as obstacles to the movement of dislocations.

Osman, H.; Borhana, A.; Tamin, M. N.

2014-06-01

162

Acute achilles tendon rupture in athletes.  

PubMed

The incidence of AT rupture has increased in recent decades. AT ruptures frequently occur in the third or fourth decade of life in sedentary individuals who play sport occasionally. Ruptures also occur in elite athletes. Clinical examination must be followed by imaging. Conservative management and early mobilization can achieve excellent results, but the rerupture rate is not acceptable for the management of young, active, or athletic individuals. Open surgery is the most common option for AT ruptures, but there are risks of superficial skin breakdown and wound problems. These problems can be prevented with percutaneous repair. PMID:23707180

Longo, Umile Giuseppe; Petrillo, Stefano; Maffulli, Nicola; Denaro, Vincenzo

2013-06-01

163

Neck curve polynomials in neck rupture model  

SciTech Connect

The Neck Rupture Model is a model that explains the scission process which has smallest radius in liquid drop at certain position. Old fashion of rupture position is determined randomly so that has been called as Random Neck Rupture Model (RNRM). The neck curve polynomials have been employed in the Neck Rupture Model for calculation the fission yield of neutron induced fission reaction of {sup 280}X{sub 90} with changing of order of polynomials as well as temperature. The neck curve polynomials approximation shows the important effects in shaping of fission yield curve.

Kurniadi, Rizal; Perkasa, Yudha S.; Waris, Abdul [Nuclear Physics and Biophysics Research Division, Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesa 10 Bandung 40132 (Indonesia)

2012-06-06

164

Tendon Ruptures Associated With Corticosteroid Therapy  

PubMed Central

In five patients, tendon ruptures occurred in association with corticosteroid therapy, either systemic or local infiltration. The chronic nature of the pain in all of these patients suggests that what we often call tendinitis may in fact be early or partial ruptures of tendons. Patients who receive local infiltration of corticosteroids should perhaps be advised of the risk of a ruptured tendon. In addition, particularly when the Achilles tendon is involved, immobilization should be utilized initially for a presumed tendinitis or early rupture, to protect the tendon from further injury. ImagesFigure 1.Figure 2.

Halpern, Alan A.; Horowitz, Bruce G.; Nagel, Donald A.

1977-01-01

165

Mitochondrial Swelling and Incipient Outer Membrane Rupture in Preapoptotic and Apoptotic Cells  

PubMed Central

Outer mitochondrial membrane (OMM) rupture was first noted in isolated mitochondria in which the inner mitochondrial membrane (IMM) had lost its selective permeability. This phenomenon referred to as mitochondrial permeability transition (MPT) refers to a permeabilized inner membrane that originates a large swelling in the mitochondrial matrix, which distends the outer membrane until it ruptures. Here, we have expanded previous electron microscopic observations that in apoptotic cells, OMM rupture is not caused by a membrane stretching promoted by a markedly swollen matrix. It is shown that the widths of the ruptured regions of the OMM vary from 6 to 250 nm. Independent of the perforation size, herniation of the mitochondrial matrix appeared to have resulted in pushing the IMM through the perforation. A large, long focal herniation of the mitochondrial matrix, covered with the IMM, was associated with a rupture of the OMM that was as small as 6 nm. Contextually, the collapse of the selective permeability of the IMM may precede or follow the release of the mitochondrial proteins of the intermembrane space into the cytoplasm. When the MPT is a late event, exit of the intermembrane space proteins to the cytoplasm is unimpeded and occurs through channels that transverse the outer membrane, because so far, the inner membrane is impermeable. No channel within the outer membrane can expose to the cytoplasm a permeable inner membrane, because it would serve as a conduit for local herniation of the mitochondrial matrix. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.

Sesso, A; Belizario, JE; Marques, MM; Higuchi, ML; Schumacher, RI; Colquhoun, A; Ito, E; Kawakami, J

2012-01-01

166

Contractions, a risk for premature rupture of fetal membranes: a new protocol with cyclic biaxial tension.  

PubMed

This study aims at investigating the effect of repeated mechanical loading on the rupture and deformation properties of fetal membranes. Ten membranes delivered by cesarean sections were tested using a custom-built inflation device which provides a multi-axial stress state. For each membrane, a group of samples was first cyclically stretched by application of pressure ranging between 10 and 40 mmHg. After cycles, samples were subjected to inflation up to rupture. Differences between mechanical parameters from cycled and uncycled samples were analyzed. Ten cycles at 40% of mean critical membrane tension--representative of mean physiologic contractions--did not affect strength and stiffness of fetal membranes but reduced the work to rupture, thus indicating that contractions might increase the risk of premature rupture of the membrane. Cyclic testing demonstrated a large hysteresis loop and irreversible deformation on the first cycle, followed by rapid stabilization on subsequent cycles. In 80% of tests, amnion ruptured first and at the periphery of the sample, under uniaxial strain state. Chorion ruptured at higher deformation levels in the middle, under biaxial strain state. PMID:22998894

Perrini, Michela; Bürzle, Wilfried; Haller, Claudia; Ochsenbein-Kölble, Nicole; Deprest, Jan; Zimmermann, Roland; Mazza, Edoardo; Ehrbar, Martin

2013-06-01

167

An earthquake in a maze: compressional rupture branching during the 11 April 2012 M8.6 off-Sumatra earthquake  

NASA Astrophysics Data System (ADS)

Geophysical observations of the 2012 Mw 8.6 Sumatra earthquake reveal unprecedented complexity of dynamic rupture. The surprisingly large magnitude results from the combination of deep extent, high stress drop and rupture of multiple faults. Back-projection source imaging indicates that the rupture occurs on distinct planes in an orthogonal conjugate fault system, with relatively slow rupture speed. The ESE-WNW ruptures add a new dimension to the seismotectonics of the Wharton Basin which was previously thought to be controlled by N-S strike-slip faulting. The rupture followed an exceptionally tortuous rupture path. It featured two episodes of branching into fault segments that were experiencing increased compressive dynamic stresses, hence increased frictional strength. By conducting 2D dynamic rupture simulations, we find that the compressional branching can only occur under slow rupture speed and low apparent friction coefficient. Poroelastic effects can also contribute by buffering the dynamic clamping. We suggest that serpentinized minerals may provide low friction, fluids and dynamic weakening down to 25 km depth, and ductile shear heating instability may provide a weakening mechanism from 40 to 60 km depth. The absence of known weakening mechanism in the intermediate depth range suggests that rupture may penetrate over velocity-strengthening regions.

Meng, L.; Ampuero, J. P.; Stock, J. M.; Duputel, Z.; Luo, Y.; Tsai, V. C.

2012-12-01

168

Spaghetti Strength  

NSDL National Science Digital Library

In this activity on page 7 of the PDF, learners explore how engineers characterize building materials. Learners test the strength of spaghetti and determine how the number of spaghetti strands affects the strength of a bundle of spaghetti. Use this activity to chemical bonds, mechanical testing, and engineering. Note: The pasta strands can be dipped in water and stuck together to more closely mimic the layers within a piece of plywood. More information about this can be found at the top of page 7, directly underneath the cartoon image. Safety note: Do not eat or drink any of the materials in this activity.

Society, American C.

2011-01-01

169

Cryogenic insulation strength and bond tester  

NASA Technical Reports Server (NTRS)

A method and apparatus for testing the tensile strength and bonding strength of sprayed-on foam insulation attached to metal cryogenic fuel tanks is described. A circular cutter is used to cut the insulation down to the surface of the metal tank to form plugs of the insulation for testing in situ on the tank. The apparatus comprises an electromechanical pulling device powered by a belt battery pack. The pulling device comprises a motor driving a mechanical pulling structure comprising a horizontal shaft connected to two bell cracks which are connected to a central member. When the lower end of member is attached to a fitting, which in turn is bonded to a plug, a pulling force is exerted on the plug sufficient to rupture it. The force necessary to rupture the plug or pull it loose is displayed as a digital read-out.

Schuerer, P. H.; Ehl, J. H.; Prasthofer, W. P. (inventors)

1985-01-01

170

EndoButton-assisted repair of distal biceps tendon ruptures.  

PubMed

This report represents a multifactorial investigation of a new technique in which a titanium EndoButton was used for repair of distal biceps tendon ruptures. Cadaveric cases were used to demonstrate the anatomic efficacy and safety of the procedure. Biomechanical testing was done to compare the fixation strength of traditional techniques with the EndoButton repair. Finally, clinical results of the repair were evaluated. In 15 fresh-frozen cadavers the mean distance of the button from the posterior interosseous nerve was 9.3 mm. Instron testing showed a mean pullout strength of 253 N for the Mitek G4 Superanchor, 177 N for a conventional bone bridge, and 584 N for the titanium button. The button was 3 times stronger than the bone bridge (P =.0001) and 2 times stronger than the Mitek anchor (P =.0007). Fourteen patients who had their tendons repaired by this technique were evaluated at a mean of 20 months postoperatively. BTE (Baltimore Therapeutic Equipment, Baltimore, MD) testing revealed recovery of 97% of flexion strength and 82% of supination strength. Patients were able to participate in an aggressive rehabilitation program and were able to regain strength and function rapidly, with satisfactory return to preinjury activities and occupations. This technique is safe, simple, and stronger than any currently available anchoring techniques and gives the surgeon a choice in bone preparation. By using a single anterior elbow approach, the development of synostosis associated with two incision techniques can be minimized. PMID:14564273

Greenberg, Jeffrey A; Fernandez, John J; Wang, Tongyu; Turner, Charles

2003-01-01

171

Papillary muscle rupture after blunt chest trauma.  

PubMed

We report a case of anterolateral papillary muscle rupture in a 22-year-old man who had blunt chest trauma caused by a car accident. Transesophageal echocardiography revealed severe mitral regurgitation caused by the rupture. He successfully underwent emergency mitral valve replacement and was discharged 9 days after the surgical correction. PMID:16581491

Cordovil, Adriana; Fischer, Claudio H; Rodrigues, Ana Clara T; Lira Filho, Edgar B; Vieira, Marcelo L C; Cury, Alexandre F; Naccarato, Gustavo A F; Valente, Carmen; Brandão, Carlos M; Pommerantzeff, Pablo M; Morhy, Samira S

2006-04-01

172

Rupture of the uterus: A changing picture  

Microsoft Academic Search

Eighty nine cases of rupture of the gravid uterus occurring over a period of 15 years with 77,133 deliveries, were analysed. The overall incidence of ruptured uteri was 1 per 866 deliveries. The patients were devided into two groups, those with a scarred uterus (47) and those with an unscarred uterus (42). Distinct differences in terms of parity, age, aetiology

J. V. Van der Merwe; W. U. A. M. Ombelet

1987-01-01

173

Urinary bladder rupture during voiding cystourethrography  

PubMed Central

Voiding cystourethrography (VCUG) is a commonly performed diagnostic procedure for the evaluation of vesicoureteral reflux with urinary tract infection or congenital renal diseases in children. The procedure is relatively simple and cost-effective, and complications are very rare. The iatrogenic complication of VCUG range from discomfort, urinary tract infection to bacteremia, as well as bladder rupture. Bladder rupture is a rare complication of VCUG, and only a few cases were reported. Bladder rupture among healthy children during VCUG is an especially uncommon event. Bladder rupture associated with VCUG is usually more common in chronically unused bladders like chronic renal failure. Presented is a case of bladder rupture that occurred during a VCUG in a healthy 9-month-old infant, due to instilled action of dye by high pressure. This injury completely healed after 7 days of operation, and it was confirmed with a postoperative cystography. The patient's bladder volume, underlying disease, velocity of the contrast media instilled, catheter size, and styles of instillation are important factors to prevent bladder rupture during VCUG. Management of bladder rupture should be individualized, but the majority of infants are treated with the operation. In conclusion, bladder rupture is a rare complication, however, delicate attention is needed in order to prevent more dire situations.

Lee, Kyong Ok; Park, Se Jin; Shin, Jae Il; Lee, Suk Young

2012-01-01

174

Rupture of wetting films caused by nanobubbles  

Microsoft Academic Search

It is now widely accepted that nanometer sized bubbles, attached at a hydrophobic silica surface, can cause rupture of aqueous wetting films due to the so-called nucleation mechanism. But the knowledge of the existence of such nanobubbles does not give an answer to how the subprocesses of this rupture mechanism operate. The aim of this paper is to describe the

K. W. Stöckelhuber; Boryan Radoev; Andreas Wenger; Hans Joachim Schulze

2004-01-01

175

Spontaneous Rupture Processes on a Bending Fault  

Microsoft Academic Search

We simulated spontaneous rupture processes on vertical bending faults, using a 3-D finite-difference method. Since shear and normal stresses on the fault depend upon its angle to the principal stresses, rupture velocity and slip ahead of a bending point vary with strike change. Moreover, slip on a bending fault is less than one on a flat fault, since a bending

Y. Kase; S. M. Day

2004-01-01

176

Rupture Velocity of Plane Strain Shear Cracks  

Microsoft Academic Search

Propagation of plane strain shear cracks is calculated numerically by using finite difference equations with second-order accuracy. The rupture model, in which stress drops gradually as slip increases, combines two different rupture criteria: (1) slip begins at a finite stress level; (2) finite energy is absorbed per unit area as the crack advances. Solutions for this model are nonsingular. In

D. J. Andrews

1976-01-01

177

Fractal avalanche ruptures in biological membranes  

NASA Astrophysics Data System (ADS)

Bilayer membranes envelope cells as well as organelles, and constitute the most ubiquitous biological material found in all branches of the phylogenetic tree. Cell membrane rupture is an important biological process, and substantial rupture rates are found in skeletal and cardiac muscle cells under a mechanical load. Rupture can also be induced by processes such as cell death, and active cell membrane repair mechanisms are essential to preserve cell integrity. Pore formation in cell membranes is also at the heart of many biomedical applications such as in drug, gene and short interfering RNA delivery. Membrane rupture dynamics has been studied in bilayer vesicles under tensile stress, which consistently produce circular pores. We observed very different rupture mechanics in bilayer membranes spreading on solid supports: in one instance fingering instabilities were seen resulting in floral-like pores and in another, the rupture proceeded in a series of rapid avalanches causing fractal membrane fragmentation. The intermittent character of rupture evolution and the broad distribution in avalanche sizes is consistent with crackling-noise dynamics. Such noisy dynamics appear in fracture of solid disordered materials, in dislocation avalanches in plastic deformations and domain wall magnetization avalanches. We also observed similar fractal rupture mechanics in spreading cell membranes.

Gözen, Irep; Dommersnes, Paul; Czolkos, Ilja; Jesorka, Aldo; Lobovkina, Tatsiana; Orwar, Owe

2010-11-01

178

Genetic basis of cranial cruciate ligament rupture (CCLR) in dogs.  

PubMed

Abstract Cranial Cruciate Ligament rupture (CCLR) is one of the most common forms of lameness in dogs and is analogous to rupture of the anterior cruciate ligament in humans, for which it can serve as a model. As there is a strong breed-related predisposition to CCLR in dogs, a study was undertaken to consider putative genetic components in susceptible dog breeds. A candidate gene, single nucleotide polymorphism (SNP) genotyping approach using MALDI-TOF mass spectrometry (Sequenom Ltd) was designed to investigate several CCLR-susceptible dog breeds and identify CCLR-associated genes/gene regions that may confer susceptibility or resistance. A meta-analysis was performed using the breed case/control candidate gene data to identify SNP associations that were common to the whole cohort of susceptible dogs. We identified SNPs in key genes involved in ligament strength, stability and extracellular matrix formation (COL5A1, COL5A2, COL1A1, COL3A1, COL11A1, COL24A1, FBN1, LOX, LTBP2) which were significantly associated with CCLR susceptibility across the dog breeds used in this study. These SNPs could have an involvement in CCLR due to a detrimental effect on ligament structure and strength. This is the first published candidate gene study that has revealed significant genetic associations with canine CCLR. PMID:24684544

Baird, Arabella Elizabeth Gardiner; Carter, Stuart D; Innes, John F; Ollier, William E; Short, Andrea D

2014-08-01

179

Do buried-rupture earthquakes trigger less landslides than surface-rupture earthquakes for reverse faults?  

NASA Astrophysics Data System (ADS)

Gorum et al. (2013, Geomorphology 184, 127-138) carried out a study on inventory compilation and statistical analyses of landslides triggered by the 2010 Mw 7.0 Haiti earthquake. They revealed that spatial distribution patterns of these landslides were mainly controlled by complex rupture mechanism and topography. They also suggested that blind-rupture earthquakes trigger fewer landslides than surface-rupture earthquakes on thrust reverse faults. Although a few lines of evidence indicate that buried-rupture earthquakes might trigger fewer landslides than surface-rupture earthquakes on reverse faults, more careful comparisons and analyses indicate that it is not always true. Instead, some cases show that a buried-rupture earthquake can trigger a larger quantity of landslides that are distributed in a larger area, whereas surface-rupture earthquakes can trigger larger but a fewer landslides distributed in a smaller area.

Xu, Chong

2014-07-01

180

Identifying Self-healing Pulses and Crack-like Ruptures in Experiments  

NASA Astrophysics Data System (ADS)

Theoretical and numerical models predict that dynamic shear ruptures generated during earth faulting can occur either as cracks or as self-healing slip pulses depending on the friction law, the boundary conditions and the geometry used in the modeling. An experimental investigation was conducted to study dynamic rupture at high rates along an incoherent (frictional) interface between two identical Homalite plates subjected to impact shear loading. The plates were held together by external pressure and one plate underwent to an edge impact near the interface. The dynamic stress field developed during the event was recorded in real time by high-speed photography used in conjunction with classical dynamic photoelasticity. In addition to high-speed photography, a recently introduced velocimetry technique based on laser interferometry was employed to record the slip rate history during sliding. The simultaneous use of the above techniques provided direct physical evidences of the rupture mode type, the exact point of rupture initiation, the sliding velocity history at a point on the interface and the rupture propagation speed. For the first time thus, we were able to conclusively identify a crack-like rupture, a self-healing slip pulse and a mixed mode of rupture in the form of sliding pulses followed by a crack. Unlike classical shear cracks in coherent interfaces of intrinsic strength and toughness, sliding areas in frictional (incoherent) interfaces seems to grow without noticeable acceleration phases and at various discreet speeds. A relatively broad head wave that emanated from the interface was observed. It was caused by the interaction between the impact wave and the preexisting static stress field. There was a cusp in the stress contours at the interface, indicating that the propagation speed was slightly faster along the interface than in the bulk. The propagation speed of the rupture tip spans the whole speed interval from sub-Rayleigh speeds to almost sonic speeds, with the exception of a narrow area between the Rayleigh wave speed and the Shear wave speed of Homalite. Supersonic trailing pulses were also observed. When the rupture speeds were supershear, Mach lines with different inclination and emanating from the rupture zone tips were discovered. Self-sustained fringe patterns propagating along the interface were identified as sliding pulses traveling ahead of the rupture tip of crack-like rupture. Behind the rupture point, robust fringe structures traveling at a constant speed (between the Rayleigh wave speed and the shear wave speed of Homalite) were detected. The above fringe structures correspond to wrinkle-like pulses propagating along the interface. In summary, the experiments provided conclusive evidence of the occurrence of various sliding rupture modes (crack-like, pulse-like or mixed) propagating dynamically along incoherent interfaces. Of particular interest here is the first experimental evidence of the formation of sliding pulses of the self-healing type leading the first direct validation of predictions made on the basis of theoretical and numerical models of dynamic shear rupture. Finally, the experiments provided hints of the dominant physical mechanisms governing the choice of various rupture modes and their evolution.

Rosakis, A. J.; Lykotrafitis, G.

2005-12-01

181

Creep rupture behavior of candidate materials for nuclear process heat applications  

SciTech Connect

Creep and stress rupture properties are determined for the candidate materials to be used in hightemperature gas-cooled reactor (HTGR) components. The materials and test methods are briefly described based on experimental results of test durations of about20000 h. The medium creep strengths of the alloys Inconel-617, Hastelloy-X, Nimonic-86, Hastelloy-S, Manaurite-36X, IN-519, and Incoloy-800H are compared showing that Inconel-617 has the best creep rupture properties in the temperature range above 800/sup 0/C. The rupture time of welded joints is in the lower range of the scatterband of the parent metal. The properties determined in different simulated HTGR atmospheres are within the scatterband of the properties obtained in air. Extrapolation methods are discussed and a modified minimum commitment method is favored.

Schubert, F.; te Heesen, E.; Bruch, U.; Cook, R.; Diehl, H.; Ennis, P.J.; Jakobeit, W.; Penkalla, H.J.; Ullrich, G.

1984-08-01

182

Dynamic Rupture and Ground Motion Modeling on Realistically Complex Strike-Slip Faults  

NASA Astrophysics Data System (ADS)

Faults are complex structures: they are geometrically complex, and have variable stress conditions and frictional behaviors along their length. In addition, faults exist in heterogeneous settings, in terms of surrounding geology, and in terms of regional and local stresses. These individual types of heterogeneity all contribute to complex dynamic rupture behaviors and ground motion distributions, as inferred from observational data and supported by previous modeling studies. In this study, we investigate the effects of individual types of complexity, and we combine different types of heterogeneity in order to enhance the realism of models of real-world faults. We use the finite element method to conduct dynamic rupture models of earthquakes on faults with complex geometry, initial stresses, frictional parameters, and surrounding geology, and with combinations of these factors, in order to investigate the effects of this complexity on fault interactions, rupture extent, and ground motion. In particular, we investigate the effect of critical weakening distance on the ability of rupture to propagate through a discontinuity in the fault trace, the effect of a small fault between the larger strands of a stepover on the ability of rupture to jump the stepover, and how zones of aseismic creep affect rupture through locked portions of the same fault. We also construct realistically complex models of the northern San Jacinto Fault, California, incorporating realistic geometry, velocity structure, and combined regional and stochastic stress fields. We find that the distribution of complexity of any type on the fault, which leads to heterogeneous fault strength, has the primary controlling effect on rupture behavior. The relative strength or weakness of the fault, rather than the actual value, is most important. We also find that the balance of the energy budget is crucial; if too much energy is redirected into fracture, rupture stops. Lastly, we find that each type of complexity affects rupture in its own way, but it is difficult to separate out the effects of individual factors in a model that incorporates many types of heterogeneity. We therefore emphasize the importance of including as many types of realistic complexity as feasible when modeling real faults.

Lozos, Julian Charles

183

Fragmentation of transversely polarized quarks probed in transverse momentum distributions  

Microsoft Academic Search

It is shown that the azimuthal dependence of the distribution of hadrons in a quark jet is a probe of the transverse spin of the quark initiating the jet. This results in a new spin-dependent fragmentation function that acts at the twist-2 level. One example of a process where it contributes is semi-inclusive deeply inelastic scattering with a transversely polarized

John Collins

1993-01-01

184

Earthquake Rupturing in Fluid-Overpressured Crust: How Common?  

NASA Astrophysics Data System (ADS)

Whether or not ruptures nucleate in fluid-overpressured crust (? v = P f/? v > 0.4) is important because pore-fluids overpressured above hydrostatic lower fault frictional strength and may also vary through the earthquake cycle, acting as an independent variable affecting fault failure. Containment of fluid overpressure is precarious because pressure-dependent activation of faults and fractures allows drainage from overpressured portions of the crust. Discharge of fluids through activated fault-fracture permeability (fault-valve action) decreases overpressure so that subsequent failure depends on the cycling of both overpressure and frictional strength as well as tectonic stress. Geometric and mechanical considerations suggest that fluid overpressures are more likely to develop and be sustained in compressional/transpressional regimes as opposed to extensional/transtensional tectonic settings. On the basis of geophysical observations and force-balance analyses, subduction interface shear zones appear to be strongly but variably overpressured to near-lithostatic levels (? v > 0.9) over the full depth range of seismogenic megathrusts. Strong overpressuring at seismogenic depths is also documented in active fold-thrust belts and in areas of ongoing compressional inversion (e.g., northern Honshu) where inherited normal faults are reactivated as steep reverse faults, requiring near-lithostatic overpressures (? v ? 1.0) at depths of rupture initiation. Evidence for overpressuring around strike-slip faults is less clear but tends to be strongest in areas of transpression. In areas of extensional tectonics coincident with particularly high fluid discharge, there is some evidence of overpressuring concentrated towards the base of the seismogenic zone. In general, because of the limited resolution of geophysical techniques, it is easier to make the case for rupture propagation through overpressured crust than to make a definitive case for the direct involvement of overpressured fluids in rupture nucleation, though in some instances the circumstantial evidence is compelling. An unresolved related issue is the heterogeneity of overpressuring. Do the active fault zones themselves serve as fluid conduits that are locally overpressured with respect to the surrounding crust?

Sibson, Richard H.

2014-04-01

185

Isolated gallbladder rupture following blunt abdominal trauma.  

PubMed

The gallbladder is a relatively well-protected organ; consequently its rupture following blunt abdominal injury is rare and usually associated with other visceral injuries. Isolated gallbladder rupture is extremely rare. We report a healthy Nigerian adult male who sustained isolated gallbladder rupture following blunt abdominal injury from riding a motor cycle (Okada). A high index of suspicion with positive bile aspirate might lead to early diagnosis. Open cholecystectomy is a safe option of treatment in a resource poor centre especially in delayed presentation and has a good outcome. PMID:23771471

Gali, B M; Ali, N; Bakari, A A; Suleiman, I E

2013-01-01

186

Application of high-velocity friction experiments to the shear rupture of a fault in an elastic half-space  

NASA Astrophysics Data System (ADS)

We developed a physics-based model for earthquake rupture by numerically simulating shear rupture along a 2D vertical fault with the dynamic frictional strength of granite under high slip velocity. Recent experimental observations indicated that the steady-state frictional strength of silica-rich igneous rocks (granite, syenite, diorite) alternate between dynamic-weakening under low velocity (V < 0.03 m/s) and dynamic-strengthening under higher velocities (V > 0.03 m/s). This strength alternation was attributed to powder-lubrication (weakening), and powder dehydration (strengthening) (Sammis et al., 2011). We used the dynamic friction law which was determined on samples of Sierra White granite under experimental velocities approaching 1 m/s (Reches and Lockner, 2010). We converted their observed friction-distance-velocity relations into an empirical friction model referred to as WEST (WEakening - STrengthening). For the simulation calculations, we used the spectral element code of Ampuero (web.gps.caltech.edu/~ampuero/software), which computes the spontaneous rupture propagation along an anti-plane shear (mode III) fracture in an elastic half-space. In the present analysis, the WEST friction model is used as the fault strength while keeping all other parameters (crust properties and stresses) the same as Version 3 of the Southern California Earthquake Center (SCEC) benchmark problem (Harris et al., 2004). This approach allows for direct comparison between the WEST rupture and the benchmark rupture with a fault of slip-weakening friction model (Rojas et al., 2008). We found the following differences between the ruptures of the two models: (1) WEST-based rupture occurs earlier at all observation points away from the nucleation zone; (2) WEST-based model has lower (~ 35%) peak velocity and shorter rise-time; and (3) WEST-based rupture shows rich, frequent alteration of slip velocity, and consequently, the simulated rupture is more complex in stress drop, displacements, and friction recovery. We discuss the significant contribution of this experimentally-based friction model to the understanding of rupture models with emphasis on slip-pulse behavior.

Liao, Zonghu; Reches, Zeev

2013-04-01

187

Tensile and stress-rupture behavior of hafnium carbide dispersed molybdenum and tungsten base alloy wires  

NASA Technical Reports Server (NTRS)

The tensile strain rate sensitivity and the stress-rupture strength of Mo-base and W-base alloy wires, 380 microns in diameter, were determined over the temperature range from 1200 K to 1600 K. Three molybdenum alloy wires; Mo + 1.1w/o hafnium carbide (MoHfC), Mo + 25w/o W + 1.1w/o hafnium carbide (MoHfC+25W) and Mo + 45w/o W + 1.1w/o hafnium carbide (MoHfC+45W), and a W + 0.4w/o hafnium carbide (WHfC) tungsten alloy wire were evaluated. The tensile strength of all wires studied was found to have a positive strain rate sensitivity. The strain rate dependency increased with increasing temperature and is associated with grain broadening of the initial fibrous structures. The hafnium carbide dispersed W-base and Mo-base alloys have superior tensile and stress-rupture properties than those without HfC. On a density compensated basis the MoHfC wires exhibit superior tensile and stress-rupture strengths to the WHfC wires up to approximately 1400 K. Addition of tungsten in the Mo-alloy wires was found to increase the long-term stress rupture strength at temperatures above 1400 K. Theoretical calculations indicate that the strength and ductility advantage of the HfC dispersed alloy wires is due to the resistance to recrystallization imparted by the dispersoid.

Yun, Hee Mann; Titran, Robert H.

1993-01-01

188

Off-fault tensile cracks: A link between geological fault observations, experiments and earthquake rupture models  

NASA Astrophysics Data System (ADS)

Motivated by the occurrence of high-angle pseudotachylite injection veins along exhumed faults, we use optical experiments and high-speed photography to interpret the origins of tensile fractures that form during dynamic shear rupture in laboratory experiments. Sub-Rayleigh (slower than the Rayleigh wave speed) shear ruptures in Homalite-100 produce damage zones consisting of a periodic array of tensile cracks. These cracks nucleate and grow within cohesive zones behind the tips of shear ruptures that propagate dynamically along interfaces with frictional and cohesive strength. The tensile cracks are produced only along one side of the interface where transient, fault-parallel, tensile stress perturbations are associated with the growing shear rupture tip. We use an analytical, linear velocity weakening, rupture model to examine the local nature of the dynamic stress field in the vicinity of the tip of the main shear rupture which grows along a weak plane (fault) with sub-Rayleigh speed. It is this stress field which is responsible for driving the off-fault mode-I microcracks that grow during the experiments. We show that (1) the orientation of the cracks can be explained by this analytical model; and (2) the cracks can be used to simultaneously constrain the constitutive behavior of the shear rupture tip. In addition, we propose an extension of this model to explain damage structures observed along exhumed faults. Results of this study represent an important bridge between geological observations of structures preserved along exhumed faults, laboratory experiments and theoretical models of earthquake propagation, potentially leading to diagnostic criteria for interpreting velocity, directivity, and static pre-stress state associated with past earthquakes on exhumed faults.

Ngo, D.; Huang, Y.; Rosakis, A.; Griffith, W. A.; Pollard, D. D.

2009-12-01

189

Gluon propagator and transverse vertices  

SciTech Connect

It is shown explicitly that in the axial gauge the Slavnov-Taylor identity contains no useful information for determining the gluon propagator through the Dyson-Schwinger equation; rather, it is the transverse vertex which plays the crucial role.

Zhang, R.B.

1985-03-15

190

Mechanical properties of high-strength steel fiber-reinforced concrete  

Microsoft Academic Search

The marked brittleness with low tensile strength and strain capacities of high-strength concrete (HSC) can be overcome by the addition of steel fibers. This paper investigated the mechanical properties of high-strength steel fiber-reinforced concrete. The properties included compressive and splitting tensile strengths, modulus of rupture, and toughness index. The steel fibers were added at the volume fractions of 0.5%, 1.0%,

P. S Song; S Hwang

2004-01-01

191

Corrosion cracking of high-strength structural steels  

Microsoft Academic Search

A study of the mechanism of corrosion cracking of high-strength carbon steels showed that the stress dependence of time-to-rupture of steels and copper, magnesium and aluminum alloys tested in tension in various media is described by the same equation. Hence it was concluded that the basic phenomena involved in corrosion cracking are common for all alloys.

F. F. Azhogin

1968-01-01

192

TRANSVERSE OSCILLATIONS IN CHROMOSPHERIC MOTTLES  

SciTech Connect

A number of recent investigations have revealed that transverse waves are ubiquitous in the solar chromosphere. The vast majority of these have been reported in limb spicules and active region fibrils. We investigate long-lived, quiet-Sun, on-disk features such as chromospheric mottles (jet-like features located at the boundaries of supergranular cells) and their transverse motions. The observations were obtained with the Rapid Oscillations in the Solar Atmosphere instrument at the Dunn Solar Telescope. The data set is comprised of simultaneous imaging in the H{alpha} core, Ca II K, and G band of an on-disk quiet-Sun region. Time-distance techniques are used to study the characteristics of the transverse oscillations. We detect over 40 transverse oscillations in both bright and dark mottles, with periods ranging from 70 to 280 s, with the most frequent occurrence at {approx}165 s. The velocity amplitudes and transverse displacements exhibit characteristics similar to limb spicules. Neighboring mottles oscillating in-phase are also observed. The transverse oscillations of individual mottles are interpreted in terms of magnetohydrodynamic kink waves. Their estimated periods and damping times are consistent with phase mixing and resonant mode conversion.

Kuridze, D.; Mathioudakis, M.; Jess, D. B.; Keenan, F. P. [Astrophysics Research Centre, School of Mathematics and Physics, Queen's University, Belfast BT7 1NN (United Kingdom); Morton, R. J.; Erdelyi, R. [Solar Physics and Space Plasma Research Centre (SP2RC), University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Dorrian, G. D., E-mail: dkuridze01@qub.ac.uk [Institute of Astronomy and Astrophysics, National Observatory of Athens, Lofos Nymfon, Thiseio, P.O. Box 20048, GR-11810 Athens (Greece)

2012-05-01

193

The Markov Theorem for transverse knots  

Microsoft Academic Search

A transverse knot is a knot that is transverse to the planes of the standard\\u000acontact structure on real 3-space. In this paper we prove the Markov Theorem\\u000afor transverse braids, which states that two transverse closed braids that are\\u000aisotopic as transverse knots are also isotopic as transverse braids. The\\u000amethods of the proof are based on Birman and

Nancy C. Wrinkle

2002-01-01

194

Consequences of expansion joint bellows rupture.  

National Technical Information Service (NTIS)

Expansion joints are used in piping systems to accommodate pipe deflections during service and to facilitate fitup. Typically, the expansion joint bellows is the thinnest part of the pressure boundary, bellows rupture frequencies are typically several ord...

W. L. Daugherty R. F. Miller D. S. Cramer

1992-01-01

195

Rupture of intracranial aneurysm during angiography  

Microsoft Academic Search

A case of rupture of intracranial aneurysm during angiography is presented. Carotid angiograms showed extravasation of contrast medium into the subarachnoid space at the base of the brain. The literature is reviewed and possible mechanisms are briefly discussed.

Shiro Waga; Akinori Kondo; Kozo Moritake; Hajime Handa

1973-01-01

196

Plantaris rupture: why is it important?  

PubMed

Plantaris muscle is accessory plantar flexor of calf, a vestigial muscle of triceps surae complex. Its importance lies in the fact that its rupture cans mimic deep vein thrombosis (DVT). Sometimes when there is rupture of Achilles tendon, intact plantaris can still cause plantar flexion at ankle presenting a confusing picture. We present one such case of plantaris rupture confused by radiology resident with DVT. A 51-year-old man had a feeling as if kicked in back of calf along with a snapping sound and severe pain while playing tennis. On seeing fluid between muscle plane and a hypoechoic structure radiology resident labelled it DVT. MRI suggested ruptured plantaris as fluid and muscle stump were seen between gastronemius and soleus. Patient was treated conservatively with rest, ice compression and elevated leg and showed significant reduction in pain and swelling. PMID:23345486

Rohilla, Seema; Jain, Nitin; Yadav, Rohtas

2013-01-01

197

Spontaneous splenic rupture in typhoid fever.  

PubMed Central

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.

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

1994-01-01

198

Acute Iliac Artery Rupture: Endovascular Treatment  

SciTech Connect

The authors present 7 patients who suffered iliac artery rupture over a 2 year period. In 5 patients, the rupture was iatrogenic: 4 cases were secondary to balloon angioplasty for iliac artery stenosis and 1 occurred during coronary angioplasty. In the last 2 patients, the rupture was secondary to iliac artery mycotic aneurysm. Direct placement of a stent-graft was performed in all cases, which was dilated until extravasation was controlled. Placement of the stent-graft was successful in all the cases, without any complications. The techniques used, results, and mid-term follow-up are presented. In conclusion, endovascular placement of a stent-graft is a quick, minimally invasive, efficient, and safe method for emergency treatment of acute iliac artery rupture, with satisfactory short- and mid-term results.

Chatziioannou, A.; Mourikis, D.; Katsimilis, J.; Skiadas, V., E-mail: bill_skiadas@yahoo.gr; Koutoulidis, V.; Katsenis, K.; Vlahos, L. [University of Athens, Radiology Department, Areteion Hospital (Greece)

2007-04-15

199

Duodenal rupture following trauma in a child.  

PubMed

We present a case of delayed presentation of a traumatic duodenal rupture in a 15-year-old boy. He presented 12 hours after falling six feet and sustaining blunt trauma to his anterior abdominal wall. On arrival in the Emergency Department he was shocked and peritonitic. After initial resuscitation he was stable and transferred to computed tomography where free retroperitoneal air and duodenal rupture was found. He was transferred to theatre where he underwent laparotomy and successful repair of the rupture. He made an uneventful recovery and was discharged nine days later. Duodenal rupture is a rare but serious complication of blunt abdominal trauma. Diagnosis is difficult but missed diagnosis and delayed presentation is associated with high morbidity and mortality. A high index for suspicion must be kept when dealing with blunt abdominal trauma to ensure this is not missed. PMID:21680305

McWhirter, Derek

2011-05-01

200

Evaluation of Steam Generator Tube Rupture Events.  

National Technical Information Service (NTIS)

The NRC Staff's review of three domestic pressurized water reactor steam generator tube rupture events has shown that no significant offsite doses or systems performance inadequacies have occurred. The plant operators and systems successfully avoided dire...

L. B. Marsh

1980-01-01

201

Management of traumatic aortic rupture.  

PubMed

A traumatic thoracic aortic injury is a severe and life-threatening clinical entity. Although largely fatal; if untreated, these injuries are amenable to surgical repair if appropriately diagnosed. Therefore, early triage of this condition is critically important. Unfortunately, aortic injuries rarely occur in isolation, and there has been no good cutoff value to help select the appropriate surgical strategy. Algorithms for the both diagnosis and treatment of traumatic thoracic aortic injury have undergone changes in recent years. There have been several case reports, retrospective series and registry data describing the treatment of patients with traumatic thoracic aortic rupture using endovascular treatment. Endovascular treatment is a less-invasive management option for polytraumatized patients. Because it is less invasive, without the need for thoracotomy or the use of heparin, endovascular repair can be performed even in acutely injured patients, without the risk of destabilizing pulmonary, head or abdominal traumatic lesions. Long-term follow-up especially in young patients is necessary after endovascular treatment. PMID:23338596

Watanabe, Ken-ichi; Fukuda, Ikuo; Asari, Yasushi

2013-12-01

202

Creep-rupture behavior of candidate Stirling engine alloys after long-term aging at 760 deg C in low-pressure hydrogen  

NASA Technical Reports Server (NTRS)

Nine candidate Stirling automotive engine alloys were aged at 760 C for 3500 hr in low pressure hydrogen or argon to determine the resulting effects on mechanical behavior. Candidate heater head tube alloys were CG-27, W545, 12RN72, INCONEL-718, and HS-188 while candidate cast cylinder-regenerator housing alloys were SA-F11, CRM-6D, XF-818, and HS-31. Aging per se is detrimental to the creep rupture and tensile strengths of the iron base alloys. The presence of hydrogen does not significantly contribute to strength degradation. Based percent highway driving cycle; CG-27 has adequate 3500 hr - 870 C creep rupture strength and SA-Fll, CRM-6D, and XF-818 have adequate 3500 hr - 775 C creep rupture strength.

Titran, R. H.

1984-01-01

203

Thin-film rupture for large slip  

Microsoft Academic Search

The rupture of thin liquid films on hydrophobic substrates, assuming large slip at the liquid-solid interface, is studied\\u000a using a recently developed strong slip lubrication model, it is shown that the rupture passes through up to three self-similar regimes with different dominant balances\\u000a and different scaling exponents. For one of these regimes the similarity is of second kind, and the

D. Peschka; A. Münch; B. Niethammer

2010-01-01

204

Left Ventricular Rupture Post Mitral Valve Replacement  

PubMed Central

Prevention is better than cure best applies here. As per many authors, posterior leaflet chordae preservation prevent Left ventricular rupture (LVR) and preserve LV geometry. We are presenting here 5 types of left ventricular rupture (LVR) post Mitral valve replacement (MVR) with different methods to repair with the advantages and disadvantages of each. The mortality rate is still very high despite the advances in cardiac surgery. Many therapeutic approaches have been adopted. Yet, none is ideal.

Sersar, Sameh I.; Jamjoom, Ahmed A.

2009-01-01

205

Effect of rolling on the high temperature tensile and stress-rupture properties of tungsten fiber-superalloy composites  

NASA Technical Reports Server (NTRS)

An investigation was conducted to determine the effects of mechanical working on the 1093 C (2000 F) tensile and stress-rupture strength of tungsten alloy/superalloy composites. Hot pressed composites containing either conventional tungsten lamp filament wire or tungsten-1% ThO2 wire and a nickel base alloy matrix were hot rolled at 1093 C (2000 F). The hot pressed and rolled composite specimens were then tested in tension and stress-rupture at 1093 C (2000 F). Rolling decreased the degree of fiber-matrix reaction as a function of time of exposure at 1093 C (2000 F). The stress-rupture properties of the rolled composites were superior to hot pressed composites containing equivalent diameter fibers. Rolling did not appreciably affect the 1093 C (2000 F) ultimate tensile strength of the composites.

Petrasek, D. W.

1974-01-01

206

Splenic artery aneurysm rupture in pregnancy.  

PubMed

Splenic artery aneurysm (SAA) is the commonest visceral artery aneurysm. It is diagnosed more frequently in younger women, with up to 95% presenting during pregnancy. Rupture is associated with a disproportionately high maternal and fetal mortality. We performed a literature search on the patient and SAA characteristics, clinical presentations, management and outcome of this serious complication. There were 32 patients in total with a mean age of 27.9 years (range 20-38). The mean SAA size was 2.25 cm (range 0.5-4 cm) and from the available data half of the ruptured SAA were 2 cm or less. Only one case (3.1%) was discovered incidentally, whilst the rest (96.9%) were found following rupture. The majority ruptured spontaneously. Most (62%) of the patients underwent SAA ligation and splenectomy. The maternal death rate was 21.9% (n=7), and fetal death rate was 15.6% (n=5). Most cases are not diagnosed until surgery following rupture. Ruptured SAA should be considered in the differential diagnosis of a pregnant patient with severe and unexplained abdominal pain. PMID:19596508

Ha, Jennifer Fong; Phillips, Michael; Faulkner, Kingsley

2009-10-01

207

Properties of inelastic yielding zones generated by in-plane dynamic ruptures—II. Detailed parameter-space study  

NASA Astrophysics Data System (ADS)

We perform a detailed parameter-space study on properties of yielding zones generated by 2-D in-plane dynamic ruptures on a planar fault with different friction laws and parameters, different initial stress conditions, different rock cohesion values, and different contrasts of elasticity and mass density across the fault. The focus is on cases corresponding to large strike-slip faults having high angle (?) to the maximum compressive background stress. The simulations and analytical scaling results show that for crack-like ruptures (1) the maximum yielding zone thickness Tmax linearly increases with rupture distance L and the ratio Tmax/L is inversely proportional to (1 +S)2 with S being the relative strength parameter; (2) the potency density ? decays logarithmically with fault normal distance at a rate depending on the stress state and S; (3) increasing rock cohesion reduces Tmax/L, resulting in faster rupture speed and higher inclination angle ? of expected microfractures on the extensional side of the fault. For slip pulses in quasi-steady state, T is approximately constant along strike with local values correlating with the maximum slip velocity (or final slip) at a location. For a bimaterial interface with ?, the energy dissipation to yielding contributes to developing macroscopically asymmetric rupture (at the scale of rupture length) with the same preferred propagation direction predicted for purely elastic cases with Coulomb friction. When ?, representative for thrust faulting, the energy dissipation to yielding leads to opposite preferred rupture propagation. In all cases, ? is higher on average on the compliant side. For both crack and pulse ruptures with ?, T decreases and ? increases for conditions representing greater depth. Significant damage asymmetry of the type observed across several large strike-slip faults likely implies persistent macroscopic rupture asymmetry (unilateral cracks, unilateral pulses or asymmetric bilateral pulses). The results on various features of yielding zones expected from this and other studies are summarized in a table along with observations from the field and laboratory experiments.

Xu, Shiqing; Ben-Zion, Yehuda; Ampuero, Jean-Paul

2012-12-01

208

Fetal tyhmus size as a predictor of histological chorioamnionitis in preterm premature rupture of membranes.  

PubMed

Abstract Objective: To predict histological chorioamnionitis (CA) in the cases of preterm premature rupture of membranes by using fetal thymus transverse and anteroposterior diameters and areal measurements. Methods: Fifty healthy and 50 patients diagnosed with preterm premature rupture of membranes (PPROM) between 24 and 37 weeks of gestation were included in the study. Fetal thymus measurements were done and repeated on a weekly basis until delivery, Furthermore white blood cell, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels were measured every other day until delivery, too. Following delivery, all patients' placentas were sent to pathology. Results: Histological CA was detected in 48% of the PPROM patients. There were no patients in either group with clinical CA. Thymus transverse diameter had 91% sensitivity, 81% specificity, 82% PPV, and 91% NPV in predicting histological CA in PPROM patients. No linear relationship was found between thymus anteroposterior diameter measurements and gestational age. Thymus area measurements have sensitivity of 75%, specificity of 81%, PPV of 78%, NPV of78% in determining CA in patients with PPROM. Conclusion: Both thymus transverse diameter and area measurement are more significant than sedimentation and CRP values in predicting histological CA. Fetal thymus measurements can be used in early diagnosis of infections among high risk patients. PMID:24089697

Aksakal, Sezin Ertürk; Kandemir, Omer; Alt?nbas, Sibel; Esin, Sertac; Muftuoglu, Kamil Hakan

2014-07-01

209

Spontaneous rupture of spleen masquerading as acute pancreatitis.  

PubMed

Splenic rupture most commonly follows blunt abdominal trauma. Nontraumatic rupture of the spleen is rare. Nontraumatic rupture of the spleen has been described in a variety of pathologic conditions, which include neoplastic, infectious, and hematologic diseases affecting the spleen. Spontaneous rupture of nondiseased spleen is extremely rare. We report a case of spontaneous rupture of spleen in a chronic alcoholic clinically simulating acute pancreatitis. PMID:24268850

Debnath, Jyotindu; Sonkar, Samrat; Sharma, Vivek; Chatterjee, Samar; Srivastava, Vikash; Khanna, Shiv Pankaj

2014-04-01

210

Effect of simulated medium-Btu coal gasifier atmospheres on the biaxial stress rupture behavior of four candidate coal gasifier alloys  

SciTech Connect

Tests were conducted to determine whether the biaxial stress rupture behavior of four alloys was adversely affected by exposure to four simulated medium-Btu coal gasifier atmospheres. The results of exposures up to approximately 500 h at temperatures between 649 and 982/sup 0/C are presented. Exposure to these atmospheres at temperatures below 900/sup 0/C did not significantly reduce the rupture properties from those measured in air. Only at 982/sup 0/C were the rupture strength and life in the simulated coal gasifier atmospheres lower than those measured in air at atmospheric pressure. Possible reasons for this reduction in strength/life are discussed. The results of detailed examination of specimen ruptures are also presented.

Horton, R.M.; Smolik, G.R.

1982-01-01

211

Recurrent uterine rupture after hysterescopic resection of the uterine septum  

PubMed Central

INTRODUCTION Uterine rupture after hysteroscopic septum resection is a rare complication, and its frequency is reported to be approximately 1–2.7%. Uterine perforation and monopolar resection during hysteroscopy are well-known risk factors for subsequent uterine rupture during pregnancy. PRESENTATION OF CASE We present a case of recurrent uterine ruptures during consecutive pregnancies in a patient who had undergone hysteroscopic septum resection for recurrent pregnancy loss. DISCUSSION Recurrent uterine rupture due to hysteroscopic septum resection in pregnancy is a very rare condition. In the present case we noted that the first two uterine ruptures resulted from uterine contractions; however, the third rupture occurred spontaneously and earlier in gestation. As each uterine rupture occurred earlier than the rupture in the previous gestation, a history of uterine rupture during pregnancy should raise provider suspicion about the possibility of earlier uterine rupture recurrence. CONCLUSION Uterine rupture may occur in pregnancies after hysteroscopic resection of the uterine septum. However, if a patient has a history of uterine rupture during previous pregnancies, the risk of uterine rupture may increase for earlier gestational ages in subsequent pregnancies. The patient must be informed about both the risks of uterine rupture during pregnancy after hysteroscopic septum resection and that recurrent ruptures may occur at earlier gestational weeks than during previous pregnancies.

Ergenoglu, Mete; Yeniel, Ahmet Ozgur; Y?ld?r?m, Nuri; Akdemir, Ali; Yucebilgin, Sait

2012-01-01

212

Creep-rupture tests of internally pressurized Hastelloy-X tubes  

NASA Technical Reports Server (NTRS)

Seamless Hastelloy-X tubes with 0.375-in. outside diameter and 0.025-in. wall thickness were tested to failure at temperatures from 1400 to 1650 F and internal helium pressures from 800 to 1800 psi. Lifetimes ranged from 58 to 3600 hr. The creep-rupture strength of the tubes was from 20 to 40 percent lower than that of sheet specimens. Larson-Miller correlations and photomicrographs of some specimens are presented.

Gumto, K. H.; Colantino, G. J.

1973-01-01

213

Fatigue and stress rupture of silicon carbide fibre-reinforced glass-ceramics  

Microsoft Academic Search

Fatigue and stress-rupture testing of unidirectional Nicalon-type silicon carbide fibre-reinforced lithium aluminosilicate glass-ceramic matrix composites is described. Tensile fatigue testing was performed at 22°C on two different composite systems to contrast the behaviour under applied stresses above and below the levels necessary to cause matrix cracking. The higher strength of the two composites was then also tested in flexural fatigue

Karl M. Prewo

1987-01-01

214

Realizing vector meson dominance with transverse charge densities  

SciTech Connect

The transverse charge density in a fast-moving nucleon is represented as a dispersion integral of the imaginary part of the Dirac form factor in the timelike region (spectral function). At a given transverse distance b the integration effectively extends over energies in a range {radical}t {approx}< 1/b, with exponential suppression of larger values. The transverse charge density at peripheral distances thus acts as a low-pass filter for the spectral function and allows one to select energy regions dominated by specific t-channel states, corresponding to definite exchange mechanisms in the spacelike form factor. We show that distances b {approx} 0.5 - 1.5 fm in the isovector density are maximally sensitive to the {rho} meson region, with only a {approx}10% contribution from higher-mass states. Soft-pion exchange governed by chiral dynamics becomes relevant only at larger distances. In the isoscalar density higher-mass states beyond the {omega} are comparatively more important. The dispersion approach suggests that the positive transverse charge density in the neutron at b {approx} 1 fm, found previously in a Fourier analysis of spacelike form factor data, could serve as a sensitive test of the isoscalar strength in the {approx}1 GeV mass region. In terms of partonic structure, the transverse densities in the vector meson region b {approx} 1 fm support an approximate mean-field picture of the motion of valence quarks in the nucleon.

Gerald Miller, Mark Strikman, Christian Weiss

2011-10-01

215

Dynamic rupture simulation with an experimentally-determined friction law leads to slip-pulse propagation  

NASA Astrophysics Data System (ADS)

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 displacement in ELSE (Chang et al., 2012). (B) Friction laws of ELSE-model and linear slip-weakening model. (C) Conceptual evolution of shear stress, slip velocity and displacement during a slip-pulse rupture (adapted from Heaton, 1990).

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

2013-12-01

216

Jumping Rupture Dependence on Friction Formulations at Strike-Slip Fault Stepovers  

NASA Astrophysics Data System (ADS)

It is well known that fault stepovers can under some circumstances allow through-going rupture, and under other circumstances cause rupture termination (e.g., Harris and Day 1993; Kase and Kuge, 1998; Duan and Oglesby, 2006). However, the effects of different friction law formulations on jumping rupture have not been extensively explored. In this study we investigate how 4 different frictional parameterizations affect the ability of rupture to jump a stepover. We compare linear slip weakening friction (Ida, 1972) and 3 forms of rate- and state-dependent friction (Dieterich, 1978, 1979; Ruina, 1983): ageing law, slip law, and slip law with strong rate-weakening (e.g., Rice, 1999, 2006; Beeler and Tullis, 2003; Rojas et al., 2009). We use the dynamic finite element method (Barall, 2008) to model earthquake rupture along 2-D strike-slip stepovers, in both extensional and compressional settings. We have found that for parameterizations with the same effective slip-weakening distance, the functional form of the friction law can greatly effect whether or not rupture is likely to jump and continue along the secondary fault segment. In particular, we find that the slip law, which has lower fracture energy for a given effective slip-weakening distance than the aging law or the linear slip-weakening law, allows rupture to jump larger stepover widths than the aging or slip-weakening law. We also investigate the effect of the Linker-Dieterich (Linker and Dieterich, 1992) dependence of state variable on normal stress. We find through preliminary models that adding normal stress dependence to the state variable delays nucleation on the secondary fault segment when compared to normal-stress independent state evolution laws. Nucleations along the secondary segments occur in areas of decreased normal stress, in both compressional and dilational stepovers. However, state-variable dependent normal stress results in an increase in state variable (fault strength) in those same areas, thereby hindering rupture. Thus, we illustrate that the ability of rupture to jump a stepover can depend strongly on the formulation of the friction law. In the future we will investigate the effects of friction law formulation on other fault geometries including dip-slip faults.

Ryan, K. J.; Oglesby, D. D.

2011-12-01

217

Effect of four simulated coal gasifier atmospheres on the biaxial stress rupture behavior of four candidate coal gasifier alloys. [Inconel 657  

SciTech Connect

Tests were conducted on four alloys (Type 310 stainless steel, Incoloy 800H, Haynes 188, and IN-657) which are candidates for use in coal gasifiers to determine whether their hundred-hour biaxial stress rupture strength and life were adversely affected by exposure to four simulated coal gasifier atmospheres (CGA). Exposure to these atmospheres at temperatures below 1172/sup 0/K did not decrease these rupture properties below those measured in air. Only at 1255/sup 0/K were the rupture properties in the various CGA atmospheres consistently below those measured in air at atmospheric pressure.

Horton, R.M.

1980-08-22

218

Effect of simulated medium-Btu coal-gasifier atmospheres on the biaxial stress-rupture behavior of four candidate coal-gasifier alloys  

SciTech Connect

Tests of four candidate alloys for internal use in coal gasifiers (Type 310 stainless steel, Incoloy 800H, Haynes 188, and IN-657) were conducted in four simulated coal gasifier atmospheres up to approximately 500 h, to determine whether their biaxial stress rupture strength and life were adversely affected. Exposure to these atmospheres at temperatures below 1172/sup 0/K did not decrease these rupture properties below those measured in air. Only at 1255/sup 0/K were the rupture properties in the various CGA atmospheres consistently below those measured in air at atmospheric pressure.

Horton, R.M.

1981-12-01

219

Time/Temperature Dependent Tensile Strength of SiC and Al2O3-Based Fibers  

NASA Technical Reports Server (NTRS)

In order to understand and model the thermomechanical behavior of fiber-reinforced composites, stress-rupture, fast-fracture, and warm-up rupture studies were conducted on various advanced SiC and Al2O3-based fibers in the,temperature range from 20 to 1400 C in air as well as in inert environments. The measured stress-rupture, fast fracture, and warm-up rupture strengths were correlated into a single master time/temperature-dependent strength plot for each fiber type using thermal activation and slow crack growth theories. It is shown that these plots are useful for comparing and selecting fibers for CMC and MMC reinforcement and that, in comparison to stress rupture tests, the fast-fracture and warm-up tests can be used for rapid generation of these plots.

Yun, Hee Mann; DiCarlo, James A.

1997-01-01

220

Rupture dynamics of a geometrically complex fault  

NASA Astrophysics Data System (ADS)

We study the propagation of a two dimensional antiplane rupture along a complex geometrical fault containing a series of kinks of different angles and intervals between the kinks. Numerical solutions are obtained using the spectral element methods developed by Vilotte, Ampuero and Komatisch. We model both periodically kinked and simple versions of randomly kinked faults. We compare our simulations with the results obtained for rupture propagation along flat faults. We find that geometrically complex differ substantially from flat faults. First, complex faults emit high frequency radiation of ?-2 type every time they encounter geometrical discontinuities, this produces a strong damping of rupture propagation. Second, the average rupture speed along the overall direction of the fault is substantially reduced and, depending on the nature of the geometrical discontinuities, ruptures may be easily stopped. Energy release rates computed assuming that the fault is flat increase as the fault becomes increasingly complex. The stress field around the fault may be described as a corridor of strongly variable stress with patches of stress increase and decrease even if the slip on the fault is continuous. Contrary to flat faults, earthquake propagation leaves behind a complex final state of stress. Our model confirms the experimental findings of many authors who worked on high speed mode I fracture.

Madariaga, R. I.; Ampuero, J.

2005-12-01

221

Effect of stress state on slow rupture propagation in subduction fault zones  

NASA Astrophysics Data System (ADS)

Slow slip events (SSEs) in subduction zones are characterized by a low rupture velocity (~1-10 km/day), long duration (days to years), and no measurable radiating seismic energy. In southwest Japan, short-term SSEs have been observed to occur preferentially along the plate interface beneath the serpentinized mantle wedge. The existence of high Poisson's ratios (~0.4) in these areas suggests that aqueous fluids are present under conditions of near-lithostatic pore pressure. These geophysical observations suggest that fluids play an important role in facilitating slow slip under low stress conditions. However, the physical mechanisms underlying the generation of SSEs are not yet fully understood. To explore the influence of stress state on the process of slow rupture along the plate interface, unstable slip experiments on simulated fault zones of serpentines (lizardite/chrysotile and antigorite) and olivine were performed in a gas-medium triaxial apparatus at room temperature and confining pressures of 60-170 MPa. We show that antigorite and olivine have friction coefficients that agree with Byerlee's law (? ~0.7), while liz/ctl has a lower friction coefficient of ~0.5. During a single unstable slip, we clearly observe an initial quasi-static slow rupture phase that is almost always followed by an unstable, high-speed rupture. We find that the velocity and duration of slow rupture propagation become lower and longer, respectively, with decreasing confining pressure (at least from 140 down to 60 MPa) and in the case of lower fault-zone strength (i.e., lizardite/chrysotile). Our experimental results suggest that the generation of SSEs is facilitated by conditions of low normal stress and low fault-zone strength along the plate interface, which may be weakened by metamorphic reactions that result in the production of hydrous phases (e.g., serpentines and talc) and/or the direct involvement of fluid itself, leading to a reduction in the effective normal stress.

Hirauchi, K.; Muto, J.; Otsuki, K.

2013-12-01

222

Hitherto unknown shear rupture mechanism as a source of instability in intact hard rocks at highly confined compression  

NASA Astrophysics Data System (ADS)

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.

Tarasov, Boris G.

2014-05-01

223

[Characteristics of duodenal ruptures depending on topographical and anatomical properties of this organ and circumstances of blunt abdominal trauma].  

PubMed

We have studied specific morphological properties of duodenal rupture depending on the topographic and anatomical features of this organ and circumstances of blunt abdominal trauma suffered in a car crash (with the victim found in the passenger compartment or involved in an automobile-pedestrian accident) and a railway crash (a train-pedestrian accident) or resulting from a blunt-force trauma, a fall from height, a fall on the stomach, and traumatic compression of the body. We took into consideration the anatomical peculiarities of the duodenal rupture, such as its circular, horseshoe, and loop-like shape. The study has demonstrated that the frequency of duodenal injury associated with a blunt abdominal trauma shows a stronger dependence on the topographical and anatomical peculiarities of duodenum than on the circumstances of the case. Specifically, the circular duodenum and especially its descending portion are more readily subjected to the damage than the organs of a different shape. The position of the break with respect to the duodenal axis is an important diagnostic signs allowing to clarify circumstances of the blunt injury. Transverse ruptures are typical of strong impacts associated with the short-term interaction between the damaging object and the affected part of the body whereas longitudinal ruptures more commonly occur as a result the long-term traumatic impact. Bile imbibition of paraduodenal and peripancreatic retroperitoneal adipose tissue may be used as an additional diagnostic sign of duodenal rupture. PMID:24428049

Pigolkin, Iu I; Dubrovin, I A; Chirkov, R N; Dubrovina, I A; Khachaturian, B S; Mosoian, A S; Dallakian, V F

2013-01-01

224

Dynamic Rupture Simulations of 11 March 2011 Tohoku Earthquake  

NASA Astrophysics Data System (ADS)

There is strong observational evidence that the 11 March 2011 Tohoku earthquake rupture reached the seafloor. This was unexpected because the shallow portion of the plate interface is believed to be frictionally stable and thus not capable of sustaining coseismic rupture. In order to explore this seeming inconsistency we have developed a two-dimensional dynamic rupture model of the Tohoku earthquake. The model uses a complex fault, seafloor, and material interface structure as derived from seismic surveys. We use a rate-and-state friction model with steady state shear strength depending logarithmically on slip velocity, i.e., there is no dynamic weakening in the model. The frictional parameters are depth dependent with the shallowest portions of the fault beneath the accretionary prism being velocity strengthening. The total normal stress on the fault is taken to be lithostatic and the pore pressure is hydrostatic until a maximum effective normal stress is reached (40 MPa in our preferred model) after which point the pore pressure follows the lithostatic gradient. We also account for poroelastic buffering of effective normal stress changes on the fault. The off-fault response is linear elastic. Using this model we find that large stress changes are dynamically transmitted to the shallowest portions of the fault by waves released by deep slip that are reflected off the seafloor. These stress changes are significant enough to drive the rupture through a velocity strengthening region that is tens of kilometers long. Rupture to the trench is therefore consistent with standard assumptions about depth-dependence of subduction zone properties, and does not require extreme dynamic weakening, shallow high stress drop asperities, or other exceptional processes. We also make direct comparisons with measured seafloor deformation and onshore 1-Hz GPS data from the Tohoku earthquake. Through these comparisons we are able to determine the sensitivity of these data to several dynamic source parameters (prestress, seismogenic depth, and the extent and frictional properties of the shallow plate interface). We find that there is a trade-off between the near-trench frictional properties and effective normal stress, particularly for onshore measurements. That is, the data can be equally well fit by either a velocity strengthening or velocity weakening near-trench fault segment, provided that compensating adjustments are also made to the maximum effective normal stress on the fault. On the other hand, the seismogenic depth is fairly well constrained from the static displacement field, independent of effective normal stress and near-trench properties. Finally, we show that a water layer (modeled as an isotropic linear acoustic material) has a negligible effect on the rupture process. That said, the inclusion of a water layer allows us to make important predictions concerning hydroacoustic signals that were observed by ocean bottom pressure sensors.

Kozdon, J. E.; Dunham, E. M.

2012-12-01

225

Field, laboratory, and theoretical investigations of fault rupture dynamics  

NASA Astrophysics Data System (ADS)

Examination of faults exhumed from seismic depths to the surface of the earth provides high resolution, continuous access to meso- and micro-scale structure that is difficult or impossible to resolve for faults at depth. Quantitative integration of field observations of fault structure with analytical, theoretical and laboratory models allow structural geologists to provide constraints on the mechanics of earthquake rupture in a dynamic sense. Field maps and thin section observations document the occurrence of pseudotachylyte (solidified melt produced during seismic slip) on small, sub-vertical strike-slip faults in granitoid rocks of the central Sierra Nevada. Measurements from these faults are used to provide constraints on ambient conditions during seismic faulting. The pseudotachylytes are less than 0.3 mm thick and are found in faults typically up to 1 cm in thickness, and total measured left-lateral offset along sampled faults is approximately 20 cm. Field and microstructural evidence indicate that the faults exploited pre-existing mineralized joints and show the following overprinting structures: mylonites more or less coeval with quartz veins, cataclasites and pseudotachylytes more or less coeval with epidote veins, and zeolite veins. Based on observations of the microstructural textures of faults combined with theoretical heat transfer and energy budget calculations, it is suggested that only a fraction (<30%) of the total offset was associated with seismic slip. The elusive nature of these pseudotachylytes demonstrates that observations in outcrop and optical microscope are not sufficient to rule out frictional melting as a consequence of seismic slip in similar fault rocks. The static stress drop is estimated on small exhumed strike-slip faults in the vicinity of the faults described in the first chapter. The faults are exposed in outcrop along their entire tip-to-tip lengths of 8-12 m. The contribution of seismic slip to the total slip along the studied cataclasite-bearing small faults may be further constrained than the previous chapter estimate (<7 cm) by measuring the length of epidote-filled, rhombohedral dilatational jogs (rhombochasms) distributed semi-periodically along the length of the faults. This affords measurement of both the rupture length and slip, yielding stress drop calculations ranging from 90 to 250 MPa, i.e., one to two orders of magnitude larger than typical seismological estimates for earthquakes. These inferred seismic ruptures occurred along small, deep-seated faults, and, given the calculated stress drops and observations that brittle faults exploited joints sealed by quartz-bearing mylonite, we conclude that these were "strong" faults. The Bear Creek fault zones localize outcrop-scale damage into tabular zones between two sub parallel boundary faults, producing a fracture-induced material contrast across the boundary faults with softer rocks between the boundary faults and intact granodiorite outside. Using detailed mapping and microstructural analysis of small fault zones to build and constrain numerical effective medium experiments, the effect of mesoscopic (outcrop-scale) damage zone fractures on the effective isotropic elastic moduli of the fault rocks is evaluated, showing that the bulk response of the fractured damage zone is strain-weakening, and can be as much as 75% more compliant than the unfractured granodiorite. Observations of the geometry and distribution of pseudotachylyte veins along faults in multiple field areas motivated the investigation of the growth of tensile microcracks in Homalite-100 around sub-rayleigh experimental shear ruptures (Laboratory Earthquakes) propagating along an interface with frictional and cohesive strength. Opening microcracks were produced only along one side of the interface where they were associated with transient tensile stress perturbation due to the propagating shear rupture. The orientation of microcracks is related to the rupture velocity and the ambient static stress field. The results of this study provide a rat

Griffith, William Ashley

226

[Successful repair of combined ventricular septal rupture and free wall rupture (double rupture); report of a case].  

PubMed

We report a case of successful surgical repair of combined ventricular septal perforation and blowout free wall cardiac rupture(double rupture) after acute myocardial infarction. The patient was a 59-year old man, who suffered an extensive acute anterior myocardial infarction. Although emergent coronary angiogram and coronary intervention was performed, he collapsed in a state of electro-mechanical dissociation in the catheterization laboratory. He was resuscitated by percutaneous cardiopulmonary support system (PCPS) and transferred to the operation theater. Infarction exclusion using bovine pericardial patch was performed. He was weaned from PCPS on day 5 after surgery and discharged hospital on day 65 with good health. PMID:23381365

Takazawa, Ippei; Kawahito, Koji; Aizawa, Kei; Misawa, Yoshio

2013-02-01

227

Application of Strength Diagnosis.  

ERIC Educational Resources Information Center

Discusses the various strength qualities (maximum strength, high- and low-load speed strength, reactive strength, rate of force development, and skill performance), noting why a training program design based on strength diagnosis can lead to greater efficacy and better performance gains for the athlete. Examples of tests used to assess strength

Newton, Robert U.; Dugan, Eric

2002-01-01

228

Large-Scale Weibull Analysis of H-451 Nuclear- Grade Graphite Specimen Rupture Data  

NASA Technical Reports Server (NTRS)

A Weibull analysis was performed of the strength distribution and size effects for 2000 specimens of H-451 nuclear-grade graphite. The data, generated elsewhere, measured the tensile and four-point-flexure room-temperature rupture strength of specimens excised from a single extruded graphite log. Strength variation was compared with specimen location, size, and orientation relative to the parent body. In our study, data were progressively and extensively pooled into larger data sets to discriminate overall trends from local variations and to investigate the strength distribution. The CARES/Life and WeibPar codes were used to investigate issues regarding the size effect, Weibull parameter consistency, and nonlinear stress-strain response. Overall, the Weibull distribution described the behavior of the pooled data very well. However, the issue regarding the smaller-than-expected size effect remained. This exercise illustrated that a conservative approach using a two-parameter Weibull distribution is best for designing graphite components with low probability of failure for the in-core structures in the proposed Generation IV (Gen IV) high-temperature gas-cooled nuclear reactors. This exercise also demonstrated the continuing need to better understand the mechanisms driving stochastic strength response. Extensive appendixes are provided with this report to show all aspects of the rupture data and analytical results.

Nemeth, Noel N.; Walker, Andrew; Baker, Eric H.; Murthy, Pappu L.; Bratton, Robert L.

2012-01-01

229

Dynamic fault rupture model of the 2008 Iwate-Miyagi Nairiku earthquake, Japan; Role of rupture velocity changes on extreme ground motions  

NASA Astrophysics Data System (ADS)

The Iwate-Miyagi Nairiku earthquake, a reverse earthquake occurred in the southern Iwate prefecture Japan (2008/6/14), produced the largest peak ground acceleration recorded to date (4g) (Aoi et al. 2008), at the West Ichinoseki (IWTH25), KiK-net strong motion station of NIED. This station which is equipped with surface and borehole accelerometers (GL-260), also recorded very high peak accelerations up to 1g at the borehole level, despite being located in a rock site. From comparison of spectrograms of the observed surface and borehole records at IWTH25, Pulido et. al (2008) identified two high frequency (HF) ground motion events located at 4.5s and 6.3s originating at the source, which likely derived in the extreme observed accelerations of 3.9g and 3.5g at IWTH25. In order to understand the generation mechanism of these HF events we performed a dynamic fault rupture model of the Iwate-Miyagi Nairiku earthquake by using the Support Operator Rupture Dynamics (SORD) code, (Ely et al., 2009). SORD solves the elastodynamic equation using a generalized finite difference method that can utilize meshes of arbitrary structure and is capable of handling geometries appropriate to thrust earthquakes. Our spontaneous dynamic rupture model of the Iwate-Miyagi Nairiku earthquake is governed by the simple slip weakening friction law. The dynamic parameters, stress drop, strength excess and critical slip weakening distance are estimated following the procedure described in Pulido and Dalguer (2009) [PD09]. These parameters develop earthquake rupture consistent with the final slip obtained by kinematic source inversion of near source strong ground motion recordings. The dislocation model of this earthquake is characterized by a patch of large slip located ~7 km south of the hypocenter (Suzuki et al. 2009). Our results for the calculation of stress drop follow a similar pattern. Using the rupture times obtained from the dynamic model of the Iwate-Miyagi Nairiku earthquake we estimated the rupture velocity as well as rupture velocity changes distribution across the fault plane based on the procedure proposed by PD09. Our results show that rupture velocity has strong variations concentrated in small patches within large slip areas (asperities). Using this dynamic model we performed the strong motion simulation at the IWTH25 borehole. We obtained that this model is able to reproduce the two HF events observed in the strong motion data. Our preliminary results suggest that the extreme acceleration pulses were induced by two strong rupture velocity acceleration events at the rupture front. References Aoi, S., T. Kunugi, and H. Fujiwara, 2008, Science, 322, 727-730. Ely, G. P., S. M. Day, and J.-B. Minster (2009), Geophys. J. Int., 177(3), 1140-1150. Pulido, N., S. Aoi, and W. Suzuki (2008), AGU Fall meeting, S33C-02. Pulido, N., and L.A. Dalguer, (2009). Estimation of the high-frequency radiation of the 2000 Tottori (Japan) earthquake based on a dynamic model of fault rupture: Application to the strong ground motion simulation, Bull. Seism. Soc. Am. 99(4), 2305-2322. Suzuki, W., S. Aoi, and H. Sekiguchi, (2009), Bull. Seism. Soc. Am. (Accepted).

Pulido Hernandez, N. E.; Dalguer Gudiel, L. A.; Aoi, S.

2009-12-01

230

Transverse structure of the nucleon  

NASA Astrophysics Data System (ADS)

In recent years parton distributions, describing longitudinal momentum, helicity and transversity distributions of quarks and gluons, have been generalized to account also for transverse degrees of freedom. Two new sets of more general distributions, Transverse Momentum Distributions (TMDs) and Generalized Parton Distributions (GPDs) were introduced to describe transverse momentum and space distributions of partons. Great progress has been made since then in measurements of different Single Spin Asymmetries (SSAs) in semi-inclusive and hard exclusive processes providing access to TMDs and GPDs respectively. Facilities world-wide involved in studies of the 3D structure of nucleon include HERMES at HERA, CLAS and Hall-A at JLab and COMPASS at CERN. TMD studies in Drell-Yan are also becoming an important part of the program of future facilities, such as JPARC, GSI and EIC. Significant progress has been achieved recently in lattice measurements of TMD moments. Studies of TMDs are also one of the main driving forces of the JLab 12 GeV upgrade project. In this talk we present an overview of the latest developments in studies of TMDs and discuss newly released results, ongoing activities, as well as some future measurements. )

Avakian, Harut

2010-02-01

231

Longitudinal and Transverse Wave Motion  

NSDL National Science Digital Library

Mechanical Waves are waves which propagate through a material medium (solid, liquid, or gas) at a wave speed which depends on the elastic and inertial properties of that medium. There are two basic types of wave motion for mechanical waves: longitudinal waves and transverse waves.

232

Transverse Bragg resonance laser amplifier  

Microsoft Academic Search

We propose and analyze a new type of optical amplifier that is formed by addition of gain in the periodic cladding of a transverse Bragg resonance waveguide [Opt. Lett. 27, 936 (2002)]. Using the coupled-wave formalism, we calculate the mode profiles, the exponential gain constant, and, for comparison, the gain enhancement compared with those of conventional semiconductor optical amplifiers. In

Amnon Yariv; Yong Xu; Shayan Mookherjea

2003-01-01

233

Transverse Magnetic Field Propellant Isolator  

NASA Technical Reports Server (NTRS)

An alternative high voltage isolator for electric propulsion and ground-based ion source applications has been designed and tested. This design employs a transverse magnetic field that increases the breakdown voltage. The design can greatly enhance the operating range of laboratory isolators used for high voltage applications.

Foster, John E.

2000-01-01

234

Anterior Cruciate Ligament Rupture and Osteoarthritis Progression  

PubMed Central

Anterior Cruciate Ligament (ACL) rupture is a common sporting injury that frequently affects young, athletic patients. Apart from the functional problems of instability, patients with ACL deficient knees also develop osteoarthritis. Although this is frequently cited as an indication for ACL reconstruction, the relationship between ACL rupture, reconstruction and the instigation and progression of articular cartilage degenerative change is controversial. The purpose of this paper is to review the published literature with regards ACL rupture and the multifactorial causes for osteoarthritis progression, and whether or not this is slowed or stopped by ACL reconstruction. There is no evidence in the published literature to support the view that ACL reconstruction prevents osteoarthritis, although it may prevent further meniscal damage. It must be recognised that this conclusion is based on the current literature which has substantial methodological limitations.

Wong, James Min-Leong; Khan, Tanvir; Jayadev, Chethan S; Khan, Wasim; Johnstone, David

2012-01-01

235

Delayed diagnosis of traumatic diaphragmatic rupture.  

PubMed

We report a case of late presentation of traumatic rupture of the diaphragm discovered incidentally on chest radiography (CXR) during an annual medical checkup. A 60-year-old man suffered severe blunt trauma from heavy steel frames collapsing against his back, resulting in pelvic and femoral fractures as well as pulmonary contusions. The patient recovered, but 10 months later CXR performed for lung cancer surveillance during an annual medical checkup revealed a traumatic rupture of the diaphragm. Video-assisted thoracic surgery was performed with reduction of the intestine and primary closure of the diaphragmatic defect. The patient recovered uneventfully. This report serves as a useful reminder that a medical history of severe blunt trauma should provoke a high index of suspicion for diaphragmatic rupture during annual medical surveillance. PMID:19779793

Mizobuchi, Teruaki; Iwai, Naomichi; Kohno, Hiromasa; Okada, Nao; Yoshioka, Tomoki; Ebana, Hiroki

2009-08-01

236

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

USGS Publications Warehouse

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.

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

2009-01-01

237

[Interventricular septum rupture following blunt chest trauma].  

PubMed

Interventricular septum rupture following blunt chest trauma is a rare cardiac injury that sometimes is difficult to diagnose. It has a high mortality rate, especially when in cases of hemodynamic instability requiring early surgical repair. We report the case of an 18-year old man who suffered blunt thoracoabdominal trauma and hemorrhagic shock who required emergency abdominal surgery on three occasions. He was diagnosed of traumatic rupture of interventricular septum that had not been detected in the initial echocardiography, but was suspected after the right heart catheterism. Urgent cardiac surgery was performed 72 hours later because of hemodynamic instability. PMID:19232209

Gandía-Martínez, Francisco; Andaluz-Ojeda, David; Martínez-Gil, Iñigo; Campo-Prieto, Alberto; Parra-Morais, Laura; Citores-González, Rafael

2009-01-01

238

Spontaneous rupture of a recurrent hepatic cystadenoma  

PubMed Central

Biliary cystadenoma is a rare cystic tumor of the middle aged woman that usually arises in the liver or occasionally in the extrahepatic bile ducts. It has a strong potential for recurrence and for malignant transformation. The lack of specific clinical and biological features hinders diagnosis before surgery. The spontaneous rupture of a hepatobiliary cystadnoma is a very rare and potentially life-threatening complication, with only two reported cases in the English literature. We report a case with spontaneous rupture of a recurrent hepatobiliary cystadenoma in a 32 year-old woman.

Elfadili, Hakim; Majbar, Anass; Zouaidia, Fouad; Elamrani, Naoufal; Sabbah, Farid; Raiss, Mohamed; Mahassini, Najat; Hrora, Abdelmalek; Ahallat, Mohamed

2010-01-01

239

Pectoralis major tendon rupture. Surgical procedures review.  

PubMed Central

Summary Pectoralis major (PM) muscle is the powerful dynamic stabiliser of the shoulder that acts as a flexor, adductor and internal rotator. The rupture of the PM tendon is a relatively rare injury that was firstly described in a French boy by Patissier in 1822 and later, in 1861, by Letenneur who reported another similiar case. To date, over 200 cases have been published. In this article we describe the clinical anatomy and the mechanism of injuries of PM and we review the surgical procedures for acute and chronic ruptures.

Merolla, Giovanni; Paladini, Paolo; Campi, Fabrizio; Porcellini, Giuseppe

2012-01-01

240

Amnion rupture sequence in previable fetuses.  

PubMed

Amnion rupture sequence is considered an uncommon, sporadic condition among liveborn infants. We have examined 1,010 previable fetuses (9-20 weeks developmental age) to determine the incidence and nature of amnion rupture sequence at this stage of development. We found 18 affected fetuses (15 spontaneous and 3 induced abortions) with the incidence of 1:56. Eleven fetuses had limb constrictions and amputations only; 7 fetuses also had nonlimb involvement, including disruptions of the craniofacial region mimicking encephalocele, unusual facial clefts, and abdominal defects. In 6 pregnancies, constrictions of the umbilical cord by amniotic bands were the cause of fetal intrauterine death. PMID:3223500

Kalousek, D K; Bamforth, S

1988-09-01

241

COMPARISON OF CLADDING CREEP RUPTURE MODELS  

SciTech Connect

The objective of this calculation is to compare several creep rupture correlations for use in calculating creep strain accrued by the Zircaloy cladding of spent nuclear fuel when it has been emplaced in the repository. These correlations are used to calculate creep strain values that are then compared to a large set of experimentally measured creep strain data, taken from four different research articles, making it possible to determine the best fitting correlation. The scope of the calculation extends to six different creep rupture correlations.

P. Macheret

2000-06-12

242

Rupture to the Trench in Dynamic Models of the Tohoku-Oki Earthquake  

NASA Astrophysics Data System (ADS)

The devastating tsunami caused by the 11 March 2011 Tohoku-Oki earthquake was much larger than conventional thinking would suggest. One of the primary reasons for the large tsunami was the ~5-10 m of seafloor uplift resulting from the inferred ~60 m of slip that extended to the trench axis along the base of the accretionary prism. However, the prism is believed to store negligible strain energy and the fault along its base is thought to be frictionally stable. Both factors suggest this region is not capable of sustaining rupture, and that earthquakes should stop well before the trench. Dynamic rupture simulations, which solve for rupture history and elastodynamic response in a fully consistent manner, provide a powerful tool for probing this seeming inconsistency. We have developed a 2-D model based on the detailed structure of the Japan trench. The model is comprised of multiple, irregularly shaped material blocks including the accretionary prism, oceanic crust layers, and mantle and crustal blocks. The fault response is modeled using rate-and-state friction. Inelastic deformation of the off-fault material, particularly in the low-strength prism, is captured using Drucker-Prager plasticity. The governing equations are solved with a provably stable, high-order finite difference method that handles complex geometries through the use of coordinate transforms. Both the initial stresses and frictional parameters vary with depth. Preliminary simulations suggest that the rupture can reach the trench even if the fault interface along the base of the accretionary prism is frictionally stable. Seismic waves released during updip rupture propagation on the shallowly dipping fault reflect off the seafloor back to the fault. These waves carry stress perturbations that unclamp the fault and transiently reduce fault strength. We also highlight the important role of material contrast across the fault. At sufficient depth, the oceanic crust becomes more compliant than the overlying mantle wedge, and bimaterial effects transiently reduce normal stress behind the front of the downward propagating rupture. This effect dramatically sharpens the rupture front at depth, likely enhancing high frequency radiation from the deepest parts of the fault.

Kozdon, J. E.; Dunham, E. M.

2011-12-01

243

Effect of Overheating on Creep-rupture Properties of S-816 Alloy at 1,500 F  

NASA Technical Reports Server (NTRS)

The effects of overheats to temperatures of 1650, 1800, 1900, and 2000 F were evaluated in terms of the changes in creep-rupture characteristics at 1500 F of S-816 alloy under stresses within the range of rupture strengths of the alloy for 100 to 1000 hours. Overheat periods were predominantly of 2-minute duration and were applied cyclically at approximately 5- or 12-hour intervals. The possible damage from overheating was believed to include internal metal structure changes induced by exposure to the higher temperatures and loss of life by creep if stress was present during the overheats.

Rowe, John P; Freeman, J W

1957-01-01

244

Linker Dependent Bond Rupture Force Measurements in Single-Molecule Junctions  

SciTech Connect

We use a modified conducting atomic force microscope to simultaneously probe the conductance of a single-molecule junction and the force required to rupture the junction formed by alkanes terminated with four different chemical link groups which vary in binding strength and mechanism to the gold electrodes. Molecular junctions with amine, methylsulfide, and diphenylphosphine terminated molecules show clear conductance signatures and rupture at a force that is significantly smaller than the measured 1.4 nN force required to rupture the single-atomic gold contact. In contrast, measurements with a thiol terminated alkane which can bind covalently to the gold electrode show conductance and force features unlike those of the other molecules studied. Specifically, the strong Au-S bond can cause structural rearrangements in the electrodes, which are accompanied by substantial conductance changes. Despite the strong Au-S bond and the evidence for disruption of the Au structure, the experiments show that on average these junctions also rupture at a smaller force than that measured for pristine single-atom gold contacts.

Frei M.; Hybertsen M.; Aradhya S.V.; Venkataraman L.

2012-02-16

245

Triggered reverse fault and earthquake due to crustal unloading, northwest Transverse Ranges, California.  

USGS Publications Warehouse

A reverse-right-oblique surface rupture, associated with a ML 2.5 earthquake, formed in a diatomite quarry near Lompoc, California, in the northwesternmost Transverse Ranges on April 7, 1981. The 575-m-long narrow zone of ruptures formed in clay interbeds in diatomite and diatomaceous shale of the Neogene Monterey Formation. The ruptures parallel bedding, dip 39o-59oS, and trend about N84oE on the north limb of an open symmetrical syncline. Maximum net slip was 25 cm; maximum reverse dip slip was 23 cm, maximum right-lateral strike slip was about 9 cm, and average net slip was about 12 cm. The seismic moment of the earthquake is estimated at 1 to 2 X 1018 dyne/cm and the static stress drop at about 3 bar. The removal of an average of about 44 m of diatomite resulted in an average load reduction of about 5 bar, which decreased the normal stress by about 3.5 bar and increased the shear stress on the tilted bedding plane by about 2 bar. The April 7, 1981, event was a very shallow bedding-plane rupture, apparently triggered by crustal unloading. -Authors

Yerkes, R. F.; Ellsworth, W. L.; Tinsley, J. C.

1983-01-01

246

? -electron theory of transverse optical excitons in semiconducting single-walled carbon nanotubes  

NASA Astrophysics Data System (ADS)

We present a quantitative theory of optical absorption polarized transverse to the tube axes in semiconducting single-walled carbon nanotubes. Within one-electron theory, transverse optical absorption occurs at an energy that is exactly in the middle of the two lowest longitudinal absorption energies. For nonzero Coulomb interactions between the ? electrons, transverse optical absorption is to an exciton state that is strongly blueshifted relative to the longitudinal excitons. Very similar behavior is observed in the ? -conjugated polymer polyparaphenylenevinylene, where the optical absorption polarized predominantly perpendicular to the polymer chain axis is blueshifted relative to the absorptions polarized predominantly along the chain axis. The binding energy of the transverse exciton in the nanotubes is considerably smaller than those of the longitudinal excitons. Electron-electron interactions also reduce the relative oscillator strength of the transverse optical absorption. Our theoretical results are in excellent agreement with recent experimental measurements in four chiral nanotubes.

Wang, Zhendong; Zhao, Hongbo; Mazumdar, Sumit

2007-09-01

247

Engineering evaluation of ruptured strainer in Building 309.  

National Technical Information Service (NTIS)

This report deals with the consequences of the ruptured steam strainer and is divided into two sections. Section 1 evaluates the engineering aspects of the ruptured steam strainer, investigates the events that culminated in the damage and considers factor...

J. N. Papenfuss

1982-01-01

248

Small bowel rupture due to blunt abdominal trauma.  

PubMed

Fourteen men with traumatic rupture of the small gut are analysed. Seven had alcohol intoxication. The diagnosis was made pre-operatively in eight. Ileal ruptures were the commonest, (11 of 14). Two patients died. PMID:263364

Minja, B M; Mahalu, W; Hiza, P R

1979-01-01

249

Asymptomatic rupture of the uterus: a case report.  

PubMed Central

Rupture of the gravid uterus is a serious obstetric emergency that threatens maternal and fetal life. In certain cases the classic clinical picture may be absent. Most asymptomatic ruptures are in the lower segment and of minor extent or are really dehiscences of scars. This paper presents a case of massive spontaneous rupture involving the entire corpus diagnosed at elective postpartum sterilization. This unusual event stimulated a review of the causes and clinical presentations of uterine rupture. Images FIG. 1 FIG. 2

Alper, M. M.; Dudley, D. K.

1984-01-01

250

D-Zero Cryostat Supplemental Rupture Disc  

SciTech Connect

The common relief and rupture disc vent line requires a double disc assembly with vented interspace for accurate disc burst pressures. The first disc must take pump and purge vacuum loading, but be set to operate at 110% of the MAWP, 18.3 psig (ASME code). The available solution is 18.3 psig with a burst tolerance of +/- psig. The interspace should be locally vented by a flow limiting vent valve to decouple the vent line backpressure from the vessel rupture disc. The second disc must take the worst case vent line backpressure, the steady state value found in D-Zero engineering note 3740.000-EN-63 with all three cryostats simultaneously venting at the fire condition into the 4-inch x 6-inch and 6-inch x 8-inch sections. This value is less than 2 psid. The maximum rupture value for the second disc must be less than the minimum rupture value for the first disc less 2 psid i.e. < 16.3.

Mulholland, G.T.; /Fermilab

1987-08-03

251

Postintubation Tracheal Ruptures - A case report -  

PubMed Central

Tracheobronchial ruptures (TBR) rarely complicate surgical procedures under general anesthesia. Seemingly uneventful intubations can result in injury to the trachea, which often manifests as hemoptysis and subcutaneous emphysema. We present 2 patients with postintubation TBR who were treated surgically and discuss considerations in the management of this potentially lethal injury.

Kim, Kyung Hwa; Choi, Jong-Bum; Kuh, Ja-Hong; Jo, Jung-Ku; Park, Hyun Kyu

2011-01-01

252

Surface Rupture in Northwest Saudi Arabia  

USGS Multimedia Gallery

Wendy McCausland of the USGS Volcano Disaster Assistance Program and Hani Zahran of the Saudi Geological Survey view the southern end of the surface fault rupture caused by a M5.4 earthquake in the Saudi Arabian desert on May 19, 2009. The ground displacements in the soft sediments of the foreground...

2010-09-28

253

Electrocardiographic changes produced by interventricular septal rupture.  

PubMed Central

The electrocardiogram was recorded during spontaneous rupture of the interventricular septum in a patient after myocardial infarction. The electrocardiographic abnormalities included an increase in the sinus rate, elevation of the ST segment, decrease in Q wave size, and increase in the height and width of the P wave.

Kerr, F; Haywood, L J

1976-01-01

254

Lower head creep-rupture sensitivity studies  

Microsoft Academic Search

During hypothetical severe nuclear reactor accidents, structural materials in the reactor vessel can relocate downward and form debris regions above the lower head. In this paper a one-dimensional model is presented that considers melt progression in the debris as well as the thermal and mechanical response of the head. Only creep rupture of the lower head is considered; however, other

S. S. Dosanjh; M. Pilch

1991-01-01

255

Cardiac Rupture Complicating Cerebral Intraarterial Thrombolytic Therapy  

Microsoft Academic Search

Early intraarterial thrombolytic therapy is recognized as a valuable treatment option in the setting of acute stroke. Cardiac rupture is a catastrophic complication of myocardial infarc- tion. The risk of this complication has been shown to increase with late coronary thrombo- lytic therapy (more than 7 hours after onset of myocardial infarction) (1) and has also been reported as a

R. B. Singh; D. A. Graeb; A. Fung; P. Teal

256

Traumatic rupture of the right subclavian artery  

PubMed Central

The case report of a patient who sustained a traumatic rupture of the right subclavian artery in a motor vehicle accident is presented. The preoperative diagnosis, surgical approach, postoperative management, and indications for angiography in traumatic lesions of the thoracic aorta and great vessels are discussed. The relevant literature is reviewed. Images

Girdwood, Robert W.; Holden, Michael P.; Ionescu, Marian I.

1972-01-01

257

What Is an Earthquake?: Rupture Models  

NSDL National Science Digital Library

In this activity, the learner will watch three animations based on actual data from fault ruptures from the two largest Southern California earthquakes in the 1990s: Landers (1992) and Northridge (1994). In Section 3, the learner will discover more about how such data is collected and analyzed.

258

Posterior compartment syndrome following ruptured Baker's cyst.  

PubMed

A 35 year old man presented with the sudden onset of left leg pain and swelling. Empirical anticoagulation for presumed deep vein thrombophlebitis was followed by acute worsening of symptoms. On further evaluation the patient was found to have a ruptured Baker's cyst and an acute posterior compartment syndrome. PMID:2256746

Petros, D P; Hanley, J F; Gilbreath, P; Toon, R D

1990-11-01

259

Delayed presentation of traumatic diaphragmatic rupture.  

PubMed

We present the case of a 57-year-old woman who suffered a delayed presentation of a traumatic diaphragmatic rupture (TDR). Because TDR is frequently missed on initial presentation, a delay between trauma and diagnosis can present a unique diagnostic dilemma for the emergency physician. Important historical clues and physical examination findings are the keys to making this diagnosis. PMID:18486412

Walchalk, Lisa R; Stanfield, Stephen C

2010-07-01

260

Simultaneous bilateral rupture of the quadriceps tendon.  

PubMed

The simultaneous, complete rupture of both quadriceps tendons is a rare event. Only 30 previous cases have been reported and the majority have had well-documented predisposing factors, such as chronic renal failure, gout, hyperparathyroidism, diabetes and obesity. We report a case which presented without any predisposing cause, and review the literature to date. PMID:2692688

Ribbans, W J; Angus, P D

1989-03-01

261

TMI2 lower head creep rupture analysis  

Microsoft Academic Search

The TMI-2 accident resulted in approximately 40% of the reactor's core melting and collecting on the lower head of the reactor pressure vessel. The severity of the accident has raised questions about the margin of safety against rupture of the lower head in this accident since all evidence seems to indicate no major breach of the vessel occurred. Scoping heat

Thinnes

1988-01-01

262

Transverse stability of Kawahara solitons  

NASA Astrophysics Data System (ADS)

The transverse stability of the planar solitons described by the fifth-order Korteweg-de Vries equation (Kawahara solitons) is studied. It is shown that the planar solitons are unstable with respect to bending if the coefficient at the fifth-derivative term is positive and stable if it is negative. This is in agreement with the dynamics of the two-dimensional Kawahara solitons.

Karpman, V. I.

1993-01-01

263

Transverse vortex dynamics in superconductors  

NASA Astrophysics Data System (ADS)

We experimentally characterize the transverse vortex motion and observe some striking features. We find large structures and peaks in the Hall resistance, which can be attributed to the long-range inhomogeneous vortex flow present in some phases of vortex dynamics. We further demonstrate the existence of a moving vortex phase between the pinned phase (peak effect) and the field induced normal state. The measurements were performed on NiZr2 -based superconducting glasses.

Lefebvre, J.; Hilke, M.; Gagnon, R.; Altounian, Z.

2006-11-01

264

The ruptured Achilles tendon: a current overview from biology of rupture to treatment.  

PubMed

The Achilles tendon (AT) is the most frequently ruptured tendon in the human body yet the aetiology remains poorly understood. Despite the extensively published literature, controversy still surrounds the optimum treatment of complete rupture. Both non-operative management and percutaneous repair are attractive alternatives to open surgery, which carries the highest complication and cost profile. However, the lack of a universally accepted scoring system has limited any evaluation of treatment options. A typical UK district general hospital treats approximately 3 cases of AT rupture a month. It is therefore important for orthopaedic surgeons to correctly diagnose and treat these injuries with respect to the best current evidence-based practice. In this review article, we discuss the relevant pathophysiology and diagnosis of the ruptured AT and summarize the current evidence for treatment. PMID:23546858

Thevendran, G; Sarraf, K M; Patel, N K; Sadri, A; Rosenfeld, P

2013-04-01

265

Rupture and dewetting of water films on solid surfaces  

Microsoft Academic Search

An experimental study was conducted to observe rupture and dewetting of water films, 0.5–2mm thick, on solid surfaces. The effects of surface roughness, wettability, protrusions on surfaces, and air entrapment between films and surfaces were studied. Film thickness measurements were made and film rupture and surface dewetting photographed. Experiments showed that liquid films ruptured first along the highest edges of

Neil Mulji; Sanjeev Chandra

2010-01-01

266

Vaginal birth after cesarean section: risk of uterine rupture with labor induction.  

PubMed

We assessed the rate of uterine rupture in patients undergoing labor induction for attempted vaginal birth after cesarean (VBAC). A retrospective study was performed of data from a computerized database. Deliveries from January 1, 1998, to June 30, 2001, in the Southern California Kaiser Permanente system were reviewed and various perinatal characteristics analyzed. A total of 16,218 patients had a prior low transverse cesarean section. Of these, 6832 (42.1%) had a trial of labor. Successful VBAC occurred in 86% of patients with spontaneous onset of labor and 66% of patients with labor induction ( p < 0.001). The uterine rupture rate was not different between patients with spontaneous or induced labor (1.0% versus 1.2%, p = 0.51). Similarly, there was no significant difference between oxytocin or prostaglandin E2 induction (1.4% versus 1.0%, p = 0.59). In our study, labor induction did not appear to increase the risk of uterine rupture in women attempting VBAC. PMID:21424988

Ouzounian, Joseph G; Miller, David A; Hiebert, Christy J; Battista, Leah R; Lee, Richard H

2011-09-01

267

Photo-piezometric study of supershear rupture  

NASA Astrophysics Data System (ADS)

We combine acoustic emission acquisition and high speed photography in order to characterize the radiation from spontaneous dynamic rupture propagation on laboratory faults in a transparent, hard resin slab. A number of previous photographic experiments document fracture propagation at supershear velocity and the radiation of a mach cone wavefront. Supershear rupture propagation has been also inferred in several large natural earthquakes. However, failure to observe any strong shock wave in the natural events has fired a debate on the amplitude and attenuation expected for the mach wavefront. Here we attempt to characterize the mach front experimentally. In our spontaneously nucleating laboratory faults, transducers detect the wavefield both close and at a distance from the fault, allowing to characterize the amplitude and the decay of (1) mach wavefronts radiated from the supershear fractures and (2) diffractions emitted by stop-and-go jerks in fracture propagation. In the relatively low frequency range, piezoelectric transducers behave essentially like accelerometers. In the high frequency range, the passage of the rupture front (both sub- and supershear) strongly dominates the acoustic emission in the immediate vicinity of the fault, as expected from the theoretically predicted strain fields in 1/?r close to the fracture tip. Thus simple piezoelectric transducers can be used both to track the passage of the rupture front and as miniature accelerometers. By correlating the fracture photographic sequences to the piezograms recorded at some distance from the fault, we find that the signature of the mach wavefront is visible but not dominant. Our interpretation is that the supershear rupture front is weakely coherent in events, as in our case, where fracture is spontaneously nucleated.

Nielsen, S. B.; Schubnel, A. J.; Taddeucci, J.; Vinciguerra, S.; Rao, S.

2009-12-01

268

On the Transverse Vibration of Wire Rope.  

National Technical Information Service (NTIS)

Two mathematical models for the transverse vibration of tensioned wire rope are compared with experimental results. The model for a string without stiffness is found to be adequate. Added mass coefficients for transverse vibration are determined experimen...

B. S. Chung S. R. Heller

1972-01-01

269

Improving Fatigue Strength of Welded Joints by Ultrasonic Impact Treatment  

Microsoft Academic Search

Summary Enhancement in fatigue performance of welded joints by Ultrasonic Impact Treatment (UIT) was evaluated with large-scale rolled beam and built-up specimens having yield strength of 345 to 760 MPa. Eighteen rolled-beam specimens having welded details at cover plates and transverse stiffeners and eight built-up specimens having only transverse stiffener details were fatigue tested after treating the weld details by

Sougata ROY

270

Transverse sacral fractures with anterior displacement  

Microsoft Academic Search

Transverse fractures of the sacrum with anterior displacement are the rarest type of transverse sacral fractures. They usually\\u000a occur at the S1–S2 region in suicide jumpers. A clinical study was performed to evaluate the diagnosis, treatment and outcome\\u000a of transverse sacral fractures with anterior displacement. We present six patients with a transverse fracture of the sacrum\\u000a with anterior displacement. All

George S. Sapkas; Andreas F. Mavrogenis; Panayiotis J. Papagelopoulos

2008-01-01

271

Why Strength Training?  

MedlinePLUS

... Physical Activity Physical Activity Share Compartir Why strength training? Research has shown that strengthening exercises are both ... person's mental and emotional health. Benefits of Strength Training There are numerous benefits to strength training regularly, ...

272

Transversity distribution functions in the valon model  

NASA Astrophysics Data System (ADS)

We use the valon model to calculate the transversity distribution functions inside the nucleon. Transversity distributions indicate the probability to find partons with spin aligned (antialigned) to the transversely polarized nucleon. The results are in good agreement with all available experimental data and also global fits.

Alizadeh Yazdi, Z.; Taghavi-Shahri, F.; Arash, F.; Zomorrodian, M. E.

2014-05-01

273

QCD Evolution of Helicity and Transversity TMDs  

SciTech Connect

We examine the QCD evolution of the helicity and transversity parton distribution functions when including also their dependence on transverse momentum. Using an appropriate definition of these polarized transverse momentum distributions (TMDs), we describe their dependence on the factorization scale and rapidity cutoff, which is essential for phenomenological applications.

Prokudin, Alexei [JLAB, Newport News, VA (United States)

2014-01-01

274

Physically Based Failure Criteria for Transverse Matrix Cracking  

NASA Technical Reports Server (NTRS)

A criterion for matrix failure of laminated composite plies in transverse tension and in-plane shear is developed by examining the mechanics of transverse matrix crack growth. Matrix cracks are assumed to initiate from manufacturing defects and can propagate within planes parallel to the fiber direction and normal to the ply mid-plane. Fracture mechanics models of cracks in unidirectional laminates, embedded plies and outer plies are developed to determine the onset and direction of propagation for unstable crack growth. The models for each ply configuration relate ply thickness and ply toughness to the corresponding in-situ ply strength. Calculated results for several materials are shown to correlate well with experimental results.

Davila, Carlos G.; Camanho, Pedro P.

2003-01-01

275

Attenuation of Radiated Ground Motion and Stresses from Three-Dimensional Supershear Ruptures  

NASA Astrophysics Data System (ADS)

Radiating shear and Rayleigh waves from supershear ruptures form Mach fronts that transmit large-amplitude ground motion and stresses to locations far from the fault. We simulate bilateral ruptures on a finite-width vertical strike-slip fault (of width W and half-length L with L >> W) breaking the surface of an elastic half-space, and focus on the wavefield out to distances comparable to L. At distances much smaller than W, two- dimensional plane-strain slip-pulse models (i.e., models in which the lateral extent of the slip zone is unbounded) [Dunham, 2005; Bhat et al., 2007] accurately predict the subsurface wavefield. Amplitudes in the shear Mach wedges of those models are undiminished with distance from the fault. When viewed from distances far greater than W, the fault is accurately modeled as a line source that produces a shear Mach cone and, on the free surface, a Rayleigh Mach wedge. Geometrical spreading of the shear Mach cone occurs radially and amplitudes there decrease with the inverse square-root of distance [Ben-Menahem and Singh, 1987]. The transition between these two asymptotic limits occurs at distances comparable to W. Similar considerations suggest that Rayleigh Mach waves suffer no attenuation in the ideally elastic medium studied here. The rate at which fault strength weakens at the rupture front exerts a strong influence on the off-fault fields only in the immediate vicinity of the fault (for both sub-Rayleigh and supershear ruptures) and at the Mach fronts of supershear ruptures. More rapid weakening generates larger amplitudes at the Mach fronts. A paper has been prepared on this topic, with title the same as for this abstract, by E. M. Dunham and H. S. Bhat, submitted to \\it{J. Geophys. Res.}

Bhat, H. S.; Dunham, E. M.

2007-12-01

276

Incorporating Undrained Pore Fuid Pressurization Into Analyses of Off-Fault Plasticity During Dynamic Rupture  

NASA Astrophysics Data System (ADS)

When considering dynamic fault rupture in fluid-saturated elastic-plastic materials, it is sensible to assume locally undrained behavior everywhere except in small diffusive boundary layers along the rupture surface. To evaluate undrained pore pressure changes, we consider here not just the linear poroelastic effect expressed in terms of the Skempton coefficient B, like in our previous work [Viesca et al., AGU Fall 2006], but also include plastic dilatancy, which, when positive, induces a fluid suction. We work in the context of Mohr-Coulomb-like plasticity, but with a Drucker-Prager type model. Plastic parts of strain increments are controlled by the Terzaghi effective stress, elastic parts by the Biot stress combination. Following earlier work of Rudnicki, the incremental elastic-plastic constitutive relation for undrained deformation has precisely the same form as for drained deformation, so long as we change the drained constitutive parameters into new undrained ones under transformation rules that we present. Spontaneous slip-weakening fault rupture is analyzed using the dynamic finite element procedures with ABAQUS Explicit, and undrained elastic-plastic properties. Results are shown for plastic zones and effects on rupture propagation, and how they are influenced by such parameters as B and ratio ? of dilatant to shear plastic strains, for a range of principal orientations and magnitudes (relative to yield) of the pre-stress state. The undrained approximation must fail in diffusive boundary layers along the slip surface [Rudnicki and Rice, JGR 2006; Dunham and Rice, AGU Fall 2006] because the predicted pore pressures will be discontinuous at the fault. We show how to extend the Rudnicki and Rice calculation of the actual pore pressure on the fault in terms of the undrained predictions to the two sides. However, because of difficulties thus far in representing this within the ABAQUS program, all results obtained as of the time of writing neglect effects of such pore pressure changes on the fault slip-weakening strength during rupture.

Viesca, R. C.; Templeton, E. L.; Rice, J. R.

2007-12-01

277

Design prediction for long term stress rupture service of composite pressure vessels  

NASA Technical Reports Server (NTRS)

Extensive stress rupture studies on glass composites and Kevlar composites were conducted by the Lawrence Radiation Laboratory beginning in the late 1960's and extending to about 8 years in some cases. Some of the data from these studies published over the years were incomplete or were tainted by spurious failures, such as grip slippage. Updated data sets were defined for both fiberglass and Kevlar composite stand test specimens. These updated data are analyzed in this report by a convenient form of the bivariate Weibull distribution, to establish a consistent set of design prediction charts that may be used as a conservative basis for predicting the stress rupture life of composite pressure vessels. The updated glass composite data exhibit an invariant Weibull modulus with lifetime. The data are analyzed in terms of homologous service load (referenced to the observed median strength). The equations relating life, homologous load, and probability are given, and corresponding design prediction charts are presented. A similar approach is taken for Kevlar composites, where the updated stand data do show a turndown tendency at long life accompanied by a corresponding change (increase) of the Weibull modulus. The turndown characteristic is not present in stress rupture test data of Kevlar pressure vessels. A modification of the stress rupture equations is presented to incorporate a latent, but limited, strength drop, and design prediction charts are presented that incorporate such behavior. The methods presented utilize Cartesian plots of the probability distributions (which are a more natural display for the design engineer), based on median normalized data that are independent of statistical parameters and are readily defined for any set of test data.

Robinson, Ernest Y.

1992-01-01

278

Design prediction for long term stress rupture service of composite pressure vessels  

NASA Astrophysics Data System (ADS)

Extensive stress rupture studies on glass composites and Kevlar composites were conducted by the Lawrence Radiation Laboratory beginning in the late 1960's and extending to about 8 years in some cases. Some of the data from these studies published over the years were incomplete or were tainted by spurious failures, such as grip slippage. Updated data sets were defined for both fiberglass and Kevlar composite stand test specimens. These updated data are analyzed in this report by a convenient form of the bivariate Weibull distribution, to establish a consistent set of design prediction charts that may be used as a conservative basis for predicting the stress rupture life of composite pressure vessels. The updated glass composite data exhibit an invariant Weibull modulus with lifetime. The data are analyzed in terms of homologous service load (referenced to the observed median strength). The equations relating life, homologous load, and probability are given, and corresponding design prediction charts are presented. A similar approach is taken for Kevlar composites, where the updated stand data do show a turndown tendency at long life accompanied by a corresponding change (increase) of the Weibull modulus. The turndown characteristic is not present in stress rupture test data of Kevlar pressure vessels. A modification of the stress rupture equations is presented to incorporate a latent, but limited, strength drop, and design prediction charts are presented that incorporate such behavior. The methods presented utilize Cartesian plots of the probability distributions (which are a more natural display for the design engineer), based on median normalized data that are independent of statistical parameters and are readily defined for any set of test data.

Robinson, Ernest Y.

1992-09-01

279

A review on delayed presentation of diaphragmatic rupture.  

PubMed

Diaphragmatic rupture is a life-threatening condition. Diaphragmatic injuries are quite uncommon and often result from either blunt or penetrating trauma. Diaphragmatic ruptures are usually associated with abdominal trauma however, it can occur in isolation. Acute traumatic rupture of the diaphragm may go unnoticed and there is often a delay between the injury and the diagnosis. A comprehensive literature search was performed using the terms "delayed presentation of post traumatic diaphragmatic rupture" and "delayed diaphragmatic rupture". The diagnostic and management challenges encountered are discussed, together with strategies for dealing with them. We have focussed on mechanism of injury, duration, presentation and site of injury, visceral herniation, investigations and different approaches for repair. We intend to stress on the importance of delay in presentation of diaphragmatic rupture and to provide a review on the available investigations and treatment methods. The enclosed case report also emphasizes on the delayed presentation, diagnostic challenges and the advantages of laparoscopic repair of delayed diaphragmatic rupture. PMID:19698091

Rashid, Farhan; Chakrabarty, Mallicka M; Singh, Rajeev; Iftikhar, Syed Y

2009-01-01

280

TRANSVERSE ECHO MEASUREMENTS IN RHIC.  

SciTech Connect

Diffusion counteracts cooling and the knowledge of diffusion rates is important for the calculation of cooling times and equilibrium beam sizes. Echo measurements are a potentially sensitive method to determine diffusion rates, and longitudinal measurements were done in a number of machines. We report on transverse echo measurements in RHIC and the observed dependence of echo amplitudes on a number of parameters for beams of gold and copper ions, and protons. In particular they examine the echo amplitudes of gold and copper ion bunches of varying intensity, which exhibit different diffusion rates from intrabeam scattering.

FISCHER, W.

2005-09-18

281

Transverse excitations in liquid Sn.  

PubMed

Transverse acoustic (TA) excitation modes were observed in inelastic x-ray scattering (IXS) spectra of liquid Sn. The excitation energies and widths of the TA modes are in good agreement with results of an ab initio molecular dynamics simulation. By comparing current correlation spectra between the experimental and theoretical results quantitatively, we have concluded that the TA modes can be detected experimentally through the quasi-TA branches in the longitudinal current correlation spectra. The lifetime and propagation length of the TA modes were determined to be ~0.7 ps and 0.8-1.0 nm, respectively, corresponding to the size of cages formed instantaneously in liquid Sn. PMID:23378432

Hosokawa, S; Munejiri, S; Inui, M; Kajihara, Y; Pilgrim, W-C; Ohmasa, Y; Tsutsui, S; Baron, A Q R; Shimojo, F; Hoshino, K

2013-03-20

282

Solving the dynamic rupture problem with different numerical approaches and constitutive laws  

USGS Publications Warehouse

We study the dynamic initiation, propagation and arrest of a 2-D in-plane shear rupture by solving the elastodynamic equation by using both a boundary integral equation method and a finite difference approach. For both methods we adopt different constitutive laws: a slip-weakening (SW) law, with constant weakening rate, and rate- and state-dependent friction laws (Dieterich-Ruina). Our numerical procedures allow the use of heterogeneous distributions of constitutive parameters along the fault for both formulations. We first compare the two solution methods with an SW law, emphasizing the required stability conditions to achieve a good resolution of the cohesive zone and to avoid artificial complexity in the solutions. Our modelling results show that the two methods provide very similar time histories of dynamic source parameters. We point out that, if a careful control of resolution and stability is performed, the two methods yield identical solutions. We have also compared the rupture evolution resulting from an SW and a rate- and state-dependent friction law. This comparison shows that despite the different constitutive formulations, a similar behaviour is simulated during the rupture propagation and arrest. We also observe a crack tip bifurcation and a jump in rupture velocity (approaching the P-wave speed) with the Dieterich-Ruina (DR) law. The rupture arrest at a barrier (high strength zone) and the barrier-healing mechanism are also reproduced by this law. However, this constitutive formulation allows the simulation of a more general and complex variety of rupture behaviours. By assuming different heterogeneous distributions of the initial constitutive parameters, we are able to model a barrier-healing as well as a self-healing process. This result suggests that if the heterogeneity of the constitutive parameters is taken into account, the different healing mechanisms can be simulated. We also study the nucleation phase duration Tn, defined as the time necessary for the crack to reach the half-length Ic. We compare the Tn values resulting from distinct simulations calculated using different constitutive laws and different sets of constitutive parameters. Our results confirm that the DR law provides a different description of the nucleation process than the SW law adopted in this study. We emphasize that the DR law yields a complete description of the rupture process, which includes the most prominent features of SW.

Bizzarri, A.; Cocco, M.; Andrews, D. J.; Boschi, E.

2001-01-01

283

Development of an extended BIEM and its application to the analysis of earthquake dynamic rupture interacting with a medium interface  

NASA Astrophysics Data System (ADS)

An extended boundary integral equation method (XBIEM) has been recently proposed for the analysis of dynamic crack growth (=dynamic earthquake rupture model) in an inhomogeneous medium consisting of homogeneous sub-regions. Originally XBIEM is applicable to non-planar geometry of cracks and medium interfaces, but it has been demonstrated only for a simple planar crack along a bimaterial interface. Here we developed a code to analyse non-planar rupture with non-planar interfaces in a mode III problem, and applied it to a dynamic rupture problem across a planar bimaterial interface to investigate the effect of medium inhomogeneity. For this purpose, we firstly derived all the displacement and displacement velocity kernels in a unified analytic discretized form, in addition to the stress kernels already derived, necessary for versatile geometry of boundaries (i.e., cracks and interfaces) and checked all the kernel components in the simulation of wave propagation across a non-planar interface cutting a homogeneous medium. Then we validated our code in a wave reflection-transmission problem across a planar bimaterial interface. Secondly, in order to realize the analysis of dynamic rupture crossing a bimaterial interface we introduced a new implicit time-stepping scheme for instantaneously interacting boundary elements on the crack and medium interface. Such interactions only appear in the crack's crossing the interface. Otherwise we can use the explicit scheme as employed for BIEM in a homogeneous medium. We validated our numerical code for the crack growth in a homogeneous medium cut with a planar interface and found that our new scheme worked well. Finally, we tackled dynamic rupture propagation on a planar fault embedded normal to the planar interface of a bimaterial. Spontaneous rupture was allowed not only on the planar main fault but also on the interfacial fault and it is controlled by different slip-weakening laws on each of them: each peak strength is individually chosen and its ratio ?=?(interface)/?(main) is chosen as one of controlling parameters. Another parameter ? is chosen as a ratio of the shear wave velocities of the bimaterial, ?=?(+)/?(-). Simulations were conducted for hundres of parameter sets of (?, ?). Our results showed two distinct rupture processes: a) one is to propagate rupture just on the prescribed fault, and b) another is to activate the subsidiary interfacial rupture, which finally results in arresting rupture on the main planar fault. Two processes were found to be clearly divided by a line in the parameter plane (?, ?). With increasing ?, rupture tends to stay on the main fault with less significant activation of subsidiary interfacial rupture and it agrees with our physical anticipation. With increasing ? from 0.7 to 1.4 (one corresponds to homogeneous), the rupture processes shift from (a) to (b). This dependency may be understandable in terms of two extreme cases: rupture approaching a free surface and rupture approaching a fixed boundary. In the former case, the traction approaches zero in the vicinity of free surface, and thus stress does not concentrate along the interface, and vice versa.

Kusakabe, T.; Kame, N.

2013-12-01

284

Premature rupture of the membranes: neonatal consequences.  

PubMed

Premature rupture of the membranes (PROM), membrane rupture before the onset of labor, occurs in 2% to 18% of pregnancies. The time from PROM to delivery (latency) is usually less than 48 hours in term pregnancy. Therefore, the risks of PROM at term are related to fetal distress, prolapsed cord, abruptio placenta, and rarely, infection. Preterm PROM (pPROM), PROM before 37 weeks' gestation, accounts for 20% to 40% of PROM, and the incidence is doubled in multiple gestations. The latency period in pPROM is inversely related to the gestational age thereby increasing the risks of oligohydramnios and infection in very premature infants and their mothers. Because pPROM is associated with 30% to 40% of premature births, pPROM is also responsible for the neonatal problems resulting from prematurity. This review examines the impact of PROM on the neonate including fetal distress, prematurity, infection, pulmonary hypoplasia, and restriction deformations. PMID:8912991

Merenstein, G B; Weisman, L E

1996-10-01

285

Fracture of the penis with urethral rupture.  

PubMed

We report a rare case of penile fracture with incomplete urethral rupture in a 25 years old male who sustained the injury during sexual intercourse. He presented with a tense haematoma on the ventral aspect of the penile shaft, associated with urethral bleeding. Per urethral catheterization was possible though it was painful. Exploration and repair of the penile fracture and urethra were performed within 16 hrs. The patient made an uneventful recovery with good erectile and voiding function. This case illustrates the value of early surgical repair of the fracture in order to prevent complications. The true incidence of penile fracture is not known even in the Western countries because it is under reported or hidden for social embracement and even it is reported to physicians it remains undiagnosed or mismanaged. Very rarely it is associated with urethral rupture. PMID:18285737

Roy, Mk; Matin, Ma; Alam, Mm; Suruzzaman, M; Rahman, Mm

2008-01-01

286

Spontaneous splenic rupture in Plasmodium vivax malaria.  

PubMed

Malaria can present with various clinical symptoms and complications. While a tertian malaria form that is especially prevalent in Korea is characterized by mild clinical progression, occasional splenic complications are known to occur. A 26-year-old Korean male soldier without prior medical history visited The Armed Forces Capital Hospital with left upper quadrant abdominal pain one day ago. Hemostasis under laparoscopic approach was attempted. The operation was converted into laparotomy due to friable splenic tissue and consequently poor hemostasis. Splenectomy was performed. The patient was discharged at postoperative day 17 without complication. While numerous diseases can result in splenic complications, such as splenic rupture, malarial infection is known as the most common cause. The incidence of malarial infection in Korea is increasing annually, and there are occasional reports of splenic rupture due to the infection, which requires attention. PMID:25025027

Kim, Kwang Min; Bae, Byung Koo; Lee, Sung Bae

2014-07-01

287

Spontaneous splenic rupture in Plasmodium vivax malaria  

PubMed Central

Malaria can present with various clinical symptoms and complications. While a tertian malaria form that is especially prevalent in Korea is characterized by mild clinical progression, occasional splenic complications are known to occur. A 26-year-old Korean male soldier without prior medical history visited The Armed Forces Capital Hospital with left upper quadrant abdominal pain one day ago. Hemostasis under laparoscopic approach was attempted. The operation was converted into laparotomy due to friable splenic tissue and consequently poor hemostasis. Splenectomy was performed. The patient was discharged at postoperative day 17 without complication. While numerous diseases can result in splenic complications, such as splenic rupture, malarial infection is known as the most common cause. The incidence of malarial infection in Korea is increasing annually, and there are occasional reports of splenic rupture due to the infection, which requires attention.

Kim, Kwang Min; Bae, Byung Koo

2014-01-01

288

[Traumatic rupture of a horseshoe kidney].  

PubMed

One-third to one-half of all patients with horseshoe kidney are asymptomatic and the condition is found incidentally. This congenital renal anomaly has shown as a predisponent condition for renal injury in blunt abdominal trauma, but often the degree of injury has a nonoperative therapy. Horseshoe kidney rupture is an exceptional pathology that require a complete diagnostic study to make an adequate management when surgical therapy is indicated. We present a fifteen-year-old male with previously unsuspected horseshoe kidney that suffered an atypical right upper-pole and mesorrenal kidney rupture after low-velocity-impact blunt abdominal trauma. A correct presurgical diagnose let a deferred surgical approach with right lower pole and horseshoe renal isthmus preservation. The trauma conditions, an excesive clinic manifestation, a clinical investigation about known congenital simultaneous anomallies and typical radiological signs, can suggest this infrequent patology. Computed tomography provides the best radiological information. PMID:16838618

Pascual Samaniego, M; Bravo Fernández, I; Ruiz Serrano, M; Ramos Martín, J A; Lázaro Méndez, J; García González, A

2006-04-01

289

Isolated right diaphragmatic rupture following blunt trauma.  

PubMed

Blunt diaphragmatic injuries are usually caused by blunt trauma or penetrating injuries. The diagnosis may be delayed or missed because of the confusing clinical and radiographic findings and the presence of multiple associated injuries. We report the case of an isolated right diaphragm rupture in a 56-year-old man who sustained blunt thoracic trauma after car accident 2 weeks before presentation. No other injuries were detected, and he was subjected to laparotomy. Diaphragmatic rupture is perceived as an emergency entity. The late appearance of such an injury, without other accompanying injuries, is rare and should be in mind by clinicians treating trauma patients who have a delayed presentation after the injury. PMID:22083696

Baloyiannis, Ioannis; Kouritas, Vasileios K; Karagiannis, Konstantinos; Spyridakis, Michalis; Efthimiou, Matheos

2011-11-01

290

Computational model of retinal photocoagulation and rupture  

NASA Astrophysics Data System (ADS)

In patterned scanning laser photocoagulation, shorter duration (< 20 ms) pulses help reduce thermal damage beyond the photoreceptor layer, decrease treatment time and minimize pain. However, safe therapeutic window (defined as the ratio of rupture threshold power to that of light coagulation) decreases for shorter exposures. To quantify the extent of thermal damage in the retina, and maximize the therapeutic window, we developed a computational model of retinal photocoagulation and rupture. Model parameters were adjusted to match measured thresholds of vaporization, coagulation, and retinal pigment epithelial (RPE) damage. Computed lesion width agreed with histological measurements in a wide range of pulse durations and power. Application of ring-shaped beam profile was predicted to double the therapeutic window width for exposures in the range of 1 - 10 ms.

Sramek, Christopher; Paulus, Yannis M.; Nomoto, Hiroyuki; Huie, Phil; Palanker, Daniel

2009-02-01

291

Tensile properties of short fiber composites with fiber strength distribution  

Microsoft Academic Search

The influence of fiber rupture, fiber pull-out and fiber tensile strength distribution on the post-cracking behavior of short-randomly-distributed fiber reinforced brittle-matrix composites has been analyzed using an approach based on the Weibull weakest-link statistics. The analysis led to the development of a predicting model for the composite bridging stress-crack opening displacement (sc - d) law—a fundamental material property necessary for

M. Maalej

2001-01-01

292

Ruptured intracranial aneurysms in the elderly  

Microsoft Academic Search

Spontaneous subarachnoid hemorrhage (SAH) is often a devastating condition and a significant cause of worldwide morbidity\\u000a and mortality. Because the percentage of senior citizens is increasing in many countries and because of the increased incidence\\u000a of SAH in elderly patients, ruptured intracranial aneurysm is an increasingly frequent pathology in western countries. Twenty\\u000a years ago, older people were considered to have

Jacques Sedat; Mustapha Dib; David Rasendrarijao; Denys Fontaine; Michel Lonjon; Philippe Paquis

2005-01-01

293

Transverse excitations in liquid metals  

NASA Astrophysics Data System (ADS)

The transverse acoustic excitation modes were detected by inelastic x-ray scattering in liquid Ga, Cu and Fe in the Q range around 10 nm-1 using a third-generation synchrotron radiation facility, SPring-8, although these liquid metals are mostly described by a simple hard-sphere liquid. Ab initio molecular dynamics simulations clearly support this finding for liquid Ga. From the detailed analyses for the S(Q,?) spectra with good statistic qualities, the lifetime of less than 1 ps and the propagating length of less than 1 nm can be estimated for the transverse acoustic phonon modes, which correspond to the lifetime and size of cages formed instantaneously in these liquid metals. The microscopic Poisson's ratio estimated from the dynamic velocities of sound is 0.42 for liquid Ga and about -0.2 for liquid transition metals, indicating a rubber-like soft and extremely hard elastic properties of the cage clusters, respectively. The origin of these microscopic elastic properties is discussed in detail.

Hosokawa, S.; Munejiri, S.; Inui, M.; Kajihara, Y.; Pilgrim, W.-C.; Baron, A. Q. R.; Shimojo, F.; Hoshino, K.

2013-02-01

294

Effects of Apparent Supersonic Ruptures for Strike-slip Rupture: Should We Consider it in the Seismic Hazard Analysis?  

NASA Astrophysics Data System (ADS)

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.

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

2009-12-01

295

Multidisciplinary management of ruptured hepatocellular carcinoma.  

PubMed

Spontaneous rupture of hepatocellular carcinoma (HCC) is a dramatic presentation of the disease. Most published studies are from Asian centers, and North American experience is limited. This study was undertaken to review the experience of ruptured HCC at a North American multidisciplinary unit. Thirty patients presenting with ruptured HCC at a tertiary care center from 1985 to 2004 were studied retrospectively and analyzed according to the demographics, clinical presentation, tumor characteristics, treatment, and outcome in four treatment groups: emergency resection, delayed resection (resection after angiographic embolization), transcatheter arterial embolization (TAE), and conservative management. Ten, 10, 7, and 3 patients underwent emergency resection, delayed resection, TAE, and conservative treatment, respectively. The mean age of all patients was 57 years, and the mean Child-Turcotte-Pugh score was 7 +/- 2. Cirrhosis was present in 57% of the patients. Seventy percent of tumors were greater than 5 cm in diameter, and 68% of patients had multiple tumors. There was a trend toward higher 30-day mortality in the emergency resection group than in the delayed resection group. One-year survival was significantly better in the delayed resection group. In selected patients, the multidisciplinary approach of angiographic embolization and delayed resection affords better short-term survival than emergency resection. PMID:16504883

Buczkowski, Andrzej K; Kim, Peter T W; Ho, Stephen G; Schaeffer, David F; Lee, Sung I; Owen, David A; Weiss, Alan H; Chung, Stephen W; Scudamore, Charles H

2006-03-01

296

Dynamics of retinal photocoagulation and rupture  

NASA Astrophysics Data System (ADS)

In laser retinal photocoagulation, short (<20 ms) pulses have been found to reduce thermal damage to the inner retina, decrease treatment time, and minimize pain. However, the safe therapeutic window (defined as the ratio of power for producing a rupture to that of mild coagulation) decreases with shorter exposures. To quantify the extent of retinal heating and maximize the therapeutic window, a computational model of millisecond retinal photocoagulation and rupture was developed. Optical attenuation of 532-nm laser light in ocular tissues was measured, including retinal pigment epithelial (RPE) pigmentation and cell-size variability. Threshold powers for vaporization and RPE damage were measured with pulse durations ranging from 1 to 200 ms. A finite element model of retinal heating inferred that vaporization (rupture) takes place at 180-190°C. RPE damage was accurately described by the Arrhenius model with activation energy of 340 kJ/mol. Computed photocoagulation lesion width increased logarithmically with pulse duration, in agreement with histological findings. The model will allow for the optimization of beam parameters to increase the width of the therapeutic window for short exposures.

Sramek, Christopher; Paulus, Yannis; Nomoto, Hiroyuki; Huie, Phil; Brown, Jefferson; Palanker, Daniel

2009-05-01

297

Estrogen protects against intracranial aneurysm rupture in ovariectomized mice.  

PubMed

Clinical observations suggest that postmenopausal women have a higher incidence of aneurysmal rupture than premenopausal women. We hypothesize that a relative deficiency in estrogen may increase the risks of aneurysmal growth and subarachnoid hemorrhage in postmenopausal women. We assessed the effects of estrogen and selective estrogen receptor subtype agonists on the development of aneurysmal rupture in ovariectomized female mice. We used an intracranial aneurysm mouse model that recapitulates the key features of human intracranial aneurysms, including spontaneous rupture. Ten- to 12-week-old ovariectomized female mice received treatment with estrogen, nonselective estrogen receptor antagonist, estrogen receptor-? agonist, or estrogen receptor-? agonist starting 6 days after aneurysm induction so that the treatments affected the development of aneurysmal rupture without affecting aneurysmal formation. Estrogen significantly reduced the incidence of ruptured aneurysms and rupture rates in ovariectomized mice. Nonselective estrogen receptor antagonist abolished the protective effect of estrogen. Although estrogen receptor-? agonist did not affect the incidence of ruptured aneurysms or rupture rates, estrogen receptor-? agonist prevented aneurysmal rupture without affecting the formation of aneurysms. The protective role of estrogen receptor-? agonist was abolished by the inhibition of nitric oxide synthase. We showed that estrogen prevented aneurysmal rupture in ovariectomized female mice. The protective effect of estrogen seemed to occur through the activation of estrogen receptor-?, a predominant subtype of estrogen receptor in human intracranial aneurysms and cerebral arteries. PMID:24732889

Tada, Yoshiteru; Wada, Kosuke; Shimada, Kenji; Makino, Hiroshi; Liang, Elena I; Murakami, Shoko; Kudo, Mari; Shikata, Fumiaki; Pena Silva, Ricardo A; Kitazato, Keiko T; Hasan, David M; Kanematsu, Yasuhisa; Nagahiro, Shinji; Hashimoto, Tomoki

2014-06-01

298

Morphological Differences between Ruptured and Unruptured Basilar Bifurcation Aneurysms  

PubMed Central

Background?Aspect ratio (AP), daughter artery ratio (DA), and lateral angle ratio (LA) have been reported in middle cerebral artery bifurcation aneurysms to correlate with rupture status. Objective?To study the differences in AP, DA, LA, and aneurysm orientation between ruptured and unruptured basilar bifurcation aneurysms. Methods?Three-dimensional (3D) angiograms of patients with basilar bifurcation aneurysms were analyzed for AP, DA, and LA. Aneurysm projection was classified as type A if the long axis of aneurysm was along basilar artery and type-B if otherwise. Results?Thirty-one ruptured and 17 unruptured aneurysms were analyzed. The APs were significantly different (p?=?0.008), 2.63?±?1.1 for ruptured aneurysms and 1.7?±?0.55 for unruptured aneurysms. AP???1.9 correlated with rupture status with 68% sensitivity and 70% specificity. Type-A configuration was significantly associated with ruptured aneurysms with an odds ratio (OR) of 5.9. LAs were 0.9?±?0.4 and 1.4?±?0.8 for ruptured and unruptured aneurysms, respectively, and the difference tended to be significant (p?=?0.56). DAs were 1.25?±?0.22 and 1.21?±?0.19 for ruptured and unruptured aneurysms without any statistical difference. Conclusion?AP?>?1.9, type-A configuration, and lower LA is associated with ruptured basilar bifurcation aneurysms. DA did not differ between ruptured and unruptured aneurysms

Ambekar, Sudheer; Madhugiri, Venkatesh; Bollam, Papireddy; Nanda, Anil

2013-01-01

299

Early coagulopathy in patients with ruptured abdominal aortic aneurysm.  

PubMed

Ruptured abdominal aortic aneurysm (AAA) is associated with a high mortality despite surgical management. Earlier reports indicate that a major cause of immediate intraoperative death in patients with ruptured AAA is related to hemorrhage due to coagulopathy. Acidosis is, besides hypothermia and hemodilution, a possible cause of coagulopathy. The aim of the present study was to investigate the incidence of coagulopathy and acidosis preoperatively in patients with ruptured AAA in relation to the clinical outcome with special regard to the influence of shock. For this purpose, 95 consecutive patients who underwent surgery for AAA (43 ruptured with shock, 12 ruptured without shock, and 40 nonruptured) were included. Coagulopathy was defined as prothrombin time (international normalized ratio [INR]) ?1.5 and acidosis was defined as base deficit ?6 mmol/L. Mortality and postoperative complications were recorded. The present study shows a state of acidosis at the start of surgery in 30 of 55 patients with ruptured AAA. However, only in 7 of 55 patients with ruptured AAA a state of preoperative coagulopathy was demonstrated. Furthermore, in our patients with shock due to ruptured AAA only 2 of 12 deaths were due to coagulopathy and bleeding. Indeed, our results show a relatively high incidence of thrombosis-related causes of death in patients with ruptured AAA, indicating a relation to an activated coagulation in these patients. These findings indicate that modern emergency management of ruptured AAA has improved in the attempt to prevent fatal coagulopathy. PMID:21733939

Fransson, Maria; Rydningen, Hans; Henriksson, Anders E

2012-01-01

300

[Evaluation of surgical repair of distal biceps tendon ruptures].  

PubMed

PURPOSE OF THE STUDY To present the results of surgical repair of ruptures of the distal tendon of the biceps brachii muscle and thus show the adequacy of this treatment. MATERIAL Between 1987 and 2006, 19 patients had surgery for distal biceps tendon rupture. Only one side was affected in each patient. All patients were men between 28 and 69 years (average age, 47.5 years) at the time of injury (surgery). When the patients were evaluated at the end of 2007, 18 patients were included, because one died a year after surgery. METHODS The surgical repair always included a single-incision anatomical reattachment into the radial tuberosity. In 11 patients, a modified Mac Reynolds method with screw and washer fixation was used; in seven patients the insertion was fixed with Mitek anchors and, in one, it was sutured to the adjacent soft tissues. The average follow-up was 7 years (range, 1 to 20.5 years). The patients were evaluated for the cause of injury, their physical activity, age, dominance of the injured arm, surgical procedure and complications. RESULTS In 18 patients surgical repair was done early and, in one, at 16 days after injury. In all of them the tendon was detached from its site of insertion, but never torn. The intra-operative complications included, in one patient, bleeding owing to iatrogenic damage to a branch of the brachial artery, and difficult separation of the tendon due to its previous healed injury in another patient. Early post-operative complications included superficial skin necrosis in one patient and transient neurological deficit of the dorsal brand of the radial nerve and of the lateral cutaneous nerve of the forearm in two and one patient, respectively. The late complications were heterotropic ossification in three patients and screw migration in the one treated by the Mac Reynolds method. Excellent results were recorded in 11 patients (61 %), and good outcomes with a slight restriction of motion or muscle strength not limiting the patient's physical activities were in six (33.5 %) patients; only one patient (5.5 %) experienced pain on moderate exercise and had recurrent heterotropic ossification. Apart from this condition, there was no difference in the frequency of complications associated with the method used. DISCUSSION Only sparse information on distal biceps tendon ruptures has been available in the relevant Czech literature and, if so, only small groups with short follow-ups have been involved. Conservative treatment or the methods of non-anatomical reattachment have poor functional outcomes. Much better results are achieved by anatomical reattachment. Based on our experience with the Mac Reynolds technique, an anterior single-incision approach using fixation with Mitek anchors can be recommended. CONCLUSIONS Early surgical repair involving anatomical reattachment from the anterior singleincision approach with two Mitek anchors is recommended when a rupture of the distal tendon insertion of the biceps brachii is diagnosed. Key words: biceps radii muscle, biceps tendon injury, tendon fixation, bone screw and washer use. PMID:19268049

Behounek, J; Hrubina, M; Skoták, M; Krumpl, O; Zahálka, M; Dvorák, J; Fucík, M

2009-02-01

301

Elastoplastic stress analysis in stainless steel fiber reinforced aluminum metal matrix laminated plates loaded transversely  

Microsoft Academic Search

Metal matrix composites provide new materials with superior properties. They give high strength and stiffness. In this study, a stainless steel fiber reinforced aluminum metal matrix laminated simple supported plate is loaded transversely. Elasto-plastic stress analysis is carried out in the laminated plate by using finite element technique. The expansion of plastic zone and residual stresses are determined in the

O. Sayman

1998-01-01

302

Intermediate Temperature Stress Rupture of Woven SiC Fiber, BN Interphase, SiC Matrix Composites in Air  

NASA Technical Reports Server (NTRS)

Tensile stress-rupture experiments were performed on woven Hi-Nicalon reinforced SiC matrix composites with BN interphases in air. Modal acoustic emission (AE) was used to monitor the damage accumulation in the composites during the tests and microstructural analysis was performed to determine the amount of matrix cracking that occurred for each sample. Fiber fractograph), was also performed for individual fiber failures at the specimen fracture surface to determine the strengths at which fibers failed. The rupture strengths were significantly worse than what would have been expected front the inherent degradation of the fibers themselves when subjected to similar rupture conditions. At higher applied stresses the rate of rupture "?as larger than at lower applied stresses. It was observed that the change in rupture rate corresponded to the onset of through-thickness cracking in the composites themselves. The primary cause of the sen,ere degradation was the ease with which fibers would bond to one another at their closest separation distances, less than 100 nanometers, when exposed to the environment. The near fiber-to-fiber contact in the woven tows enabled premature fiber failure over large areas of matrix cracks due to the stress-concentrations created b), fibers bonded to one another after one or a few fibers fail. i.e. the loss of global load sharing. An@, improvement in fiber-to-fiber separation of this composite system should result in improved stress- rupture properties. A model was den,eloped in order to predict the rupture life-time for these composites based on the probabilistic nature of indin,idual fiber failure at temperature. the matrix cracking state during the rupture test, and the rate of oxidation into a matrix crack. Also incorporated into the model were estimates of the stress-concentration that would occur between the outer rim of fibers in a load-bearing bundle and the unbridged region of a matrix crack after Xia et al. For the lower stresses, this source of stress-concentration was the likely cause for initial fiber failure that would trigger catastrophic failure of the composite.

Morscher, Gregory N.; Levine, Stanley (Technical Monitor)

2000-01-01

303

Transverse-longitudinal integrated resonator  

DOEpatents

A transverse-longitudinal integrated optical resonator (TLIR) is disclosed which includes a waveguide, a first and a second subwavelength resonant grating in the waveguide, and at least one photonic band gap resonant structure (PBG) in the waveguide. The PBG is positioned between the first and second subwavelength resonant gratings. An electro-optic waveguide material may be used to permit tuning the TLIR and to permit the TLIR to perform signal modulation and switching. The TLIR may be positioned on a bulk substrate die with one or more electronic and optical devices and may be communicably connected to the same. A method for fabricating a TLIR including fabricating a broadband reflective grating is disclosed. A method for tuning the TLIR's transmission resonance wavelength is also disclosed.

Hutchinson, Donald P [Knoxville, TN; Simpson, Marcus L [Knoxville, TN; Simpson, John T [Knoxville, TN

2003-03-11

304

The Energy Budget of Earthquake Rupture: a View From Spontaneous Rupture Modeling and Finite-Source Models  

NASA Astrophysics Data System (ADS)

It is a common and frustrating experience of many dynamic modelers to initiate spontaneous rupture calculations that subsequently abort before rupturing to the desired earthquake size [Nielsen and Olsen, 2000; Oglesby and Day, 2002]. Source parameters in such dynamic source models are strongly correlated, but stress drop is the main factor affecting the distribution of the other dynamic rupture parameters. Additionally, the position of the hypocenter exerts a strong influence on the dynamic properties of the earthquake, and certain hypocenter positions are not plausible as those would not lead to spontaneous rupture propagation. To further investigate this last statement, we analyze the energy budget during earthquake rupture using spontaneous dynamic rupture calculations and finite-source rupture models. In describing the energy budget during earthquake rupture, we follow Favreau and Archuleta [2003]. Each point on the fault contributes to the radiated seismic energy Ers = Eel - Efr - Erx, where Eel denotes the elasto-static energy and Efr the fracture energy. In this study we neglect for simplicity the relaxation work Erx spent during the stopping of the earthquake. A rupture can be characterized by locally negative seismic energy density values, but its integral over the fault plane must be positive. The fundamental condition for rupture growth is therefore that the integral of Ers on the rupture area remains always positive during rupture propagation. Based on a simple energy budget calculation, we focus on identifying those target slip/stress distribution in dynamic rupture modeling that for a given hypocenter location fail to rupture spontaneously. Additionally, we study the energy budget of finite-source rupture models by analyzing the integrated seismic energy for the inferred slip maps using also hypocenter positions other than the network location. These results indicate how rupture was promoted for the true hypocenter while randomized hypocenters may not have been able to sustain a large earthquake. Our approach helped us both to speed up the computation of successful spontaneous rupture models, as well as to construct dynamically consistent rupture models for strong motion prediction.

Mai, P.; Guatteri, M.

2003-12-01

305

Theory of Transverse Spin and Transverse Structure of the Nucleon  

NASA Astrophysics Data System (ADS)

Large single transverse spin asymmetries (SSA) observed in various collision processes opened a new window to disentangle QCD dynamics and quark-gluon substructure of the nucleon. Since SSA is a ``naively T-odd'' observable, it can only occur as an interference between the scattering amplitudes which have different complex phases in a time-reversal invariant theory like QCD. A conventional framework for hard inclusive processes, i.e. perturbative QCD in the twist-2 level, can only give rise to a negligible asymmetry and thus can not explain the observed data. Understanding the origin of the large SSAs requires the extention of the framework of the QCD hard processes, and by now QCD mechanisms leading to large SSAs have been clarified in greater detail. These mechanisms based on different perspectives introduce new concepts describing the nucleon structure not present in the conventional parton model, such as ``parton's intrinsic transverse momentum'' and ``multi-parton correlations.'' Precise and unambiguous definition of these ideas requires much more careful theoretical analyses than the twist-2 case, in particular, in connection with the universality of the parton distribution/fragmentation functions, gauge invariance and factorization properties of the cross sections. In the literature, QCD mechanisms for SSAs are often classified into two categories. One is based on the (naively) ``T-odd'' distribution and fragmentation functions in the transverse momentum dependent (TMD) factorization approach. Sivers and Collins functions are typical examples for this one. The other one is based on the twist-3 quark-gluon (more generally, multi-parton such as triple-gluon) correlation functions in the collinear factorization approaches. The former mechanism can describe SSAs in the small-pT region (pTQ) as a leading-twist effect, while the latter one describes SSAs in the large pT region as a twist-3 effect. Both approaches have been applied to study SSAs in various processes, such as semi-inclusive deep-inelestic-scattering (SIDIS), Drell-Yan processes, p^ p ->h X (h=,, etc) etc, for which experimental measurements are ongoing at DESY, CERN, J-Lab and BNL-RHIC etc. Although the starting points of the analysis and the applicable kinematic region for these two mechanisms are different, they are shown to give identical SSAs in the intermediate region of pT for the ``Sivers'' type SSA. Universality of the TMD functions and the factorization property with TMD functions have been studied in detail. Gauge invariance and the factorization property of the twist-3 cross section in the latter approach is also understood. In this talk, I will first review recent developments in the theoretical frameworks for SSAs described above, and then I will present our recent works on SSAs based on the twist-3 mechanisms. I will discuss the azimuthal structure of the twist-3 single-spin-dependent cross section for SIDIS and AN for p^ p->h X including all kinds of pole contributions.

Koike, Yuji

2009-10-01

306

Transverse Reinforcement in Reinforced Concrete Columns  

NASA Astrophysics Data System (ADS)

In the article we are dealing with the influence of transverse reinforcement to the resistance of a cross-section of the reinforced concrete columns and also with the effective detailing of the column reinforcement. We are verifying the correctness of design guides for detailing of transverse reinforcement. We are also taking into account the diameter of stirrups and its influence over transverse deformation of column.

Grambli?ka, Štefan; Veróny, Peter

2013-11-01

307

[Traumatic rupture of the anterior urethra. Apropos of 18 cases].  

PubMed

The authors report a retrospective series of 18 cases of rupture of the anterior urethra, with a mean age of 25 years (range: 10 to 45 years). The mechanism of the lesion was trauma by falling onto the perineum (12 cases), road accident (4 cases) and sexual intercourse (2 cases). Urine drainage was ensured by suprapubic catheter (15 cases) or urethral catheter (1 case). The two cases of rupture of the urethra associated with lesions of the corpora cavernosa required urgent surgical repair. In the other cases, simple urine drainage was sufficient to treat partial ruptures of the urethra (11 cases) with only one case of urethral structure. However, end-to-end urethrorraphy was performed in the 4 patients with total rupture of the urethra, with early failure in 3 cases, attributed to delayed surgery. Finally, the course of urethral rupture associated with rupture of the corpora, cavernosa was favourable in terms of both micturition and sexual function. PMID:9480639

Trifa, M; Njeh, M; Bahloul, A; Jemal, S; Mhiri, M N

1997-01-01

308

Magnetic field strength of active region filaments  

NASA Astrophysics Data System (ADS)

Aims: We study the vector magnetic field of a filament observed over a compact active region neutral line. Methods: Spectropolarimetric data acquired with TIP-II (VTT, Tenerife, Spain) of the 10 830 Å spectral region provide full Stokes vectors that were analyzed using three different methods: magnetograph analysis, Milne-Eddington inversions, and PCA-based atomic polarization inversions. Results: The inferred magnetic field strengths in the filament are around 600-700 G by all these three methods. Longitudinal fields are found in the range of 100-200 G whereas the transverse components become dominant, with fields as high as 500-600 G. We find strong transverse fields near the neutral line also at photospheric levels. Conclusions: Our analysis indicates that strong (higher than 500 G, but below kG) transverse magnetic fields are present in active region filaments. This corresponds to the highest field strengths reliably measured in these structures. The profiles of the helium 10 830 Å lines observed in this active region filament are dominated by the Zeeman effect.

Kuckein, C.; Centeno, R.; Martínez Pillet, V.; Casini, R.; Manso Sainz, R.; Shimizu, T.

2009-07-01

309

Emergency percutaneous treatment of arterial iliac axis ruptures  

Microsoft Academic Search

The objective of this paper is to assess the feasibility and effectiveness of emergency percutaneous treatment of ruptures\\u000a of the iliac axis. In 5 years, we observed 13 patients (mean age, 62.1 years), 11 with rupture of the external iliac artery\\u000a and two with rupture of the common iliac artery (six traumatic and seven iatrogenic). All patients were treated with stent\\u000a grafts.

Domenico Laganà; Gianpaolo Carrafiello; Monica Mangini; Andrea Giorgianni; Domenico Lumia; Salvatore Cuffari; Carlo Fugazzola

2007-01-01

310

Indocyanine green angiographic features of traumatic choroidal ruptures  

Microsoft Academic Search

Purpose To investigate the indocyanine green (ICG) angiographic findings of healed traumatic choroidal ruptures.Methods Three eyes of two patients with choroidal ruptures underwent both fluorescein angiography and ICG angiography with a digital high-resolution system.Results Fundus examination showed healed choroidal ruptures in all three eyes. Two of the eyes had old macular scars and one eye had a recent choroidal neovascular

Ahmet Akman; Sibel Kadayifcilar; Sibel Oto; Pinar Aydin

1998-01-01

311

Uterine rupture following termination of pregnancy in a scarred uterus.  

PubMed

We present a series of two cases complicated by uterine rupture following termination of pregnancy (TOP) in the 1st and 2nd trimesters using misoprostol in women with caesarean section scar. Current literature and practise have also been reviewed on ruptured uterus in women with caesarean section scar undergoing TOP using misoprostol; the diagnosis of adherent placenta in the 1st and 2nd trimesters in women with previous caesarean uterine scar; and likely implications of a ruptured uterus. PMID:24456452

Bika, O; Huned, D; Jha, S; Selby, K

2014-02-01

312

Partial rupture of the quadriceps muscle in a child  

Microsoft Academic Search

BACKGROUND: The quadriceps femoris muscle ruptures usually occur in the middle-aged population. We present a 4-year-old patient with partial rupture of the quadriceps femoris muscle. To our knowledge, this is the youngest patient reported with a quadriceps femoris muscle rupture. CASE PRESENTATION: A 4-year-old girl admitted to our clinic with left knee pain and limitation in knee movements. Her father

Gokhan Aydemir; Selami Cakmak; Secil Aydinoz

2010-01-01

313

Experimental observation of ruptures propagating on heterogeneous interfaces  

NASA Astrophysics Data System (ADS)

We present experimental observations of a propagating rupture interacting with one or several mechanical heterogeneities. We developed a friction laboratory experiment where a soft elastic solid slides past a rigid flat plate. The system is coupled to an original medical imaging technique, ultrasound speckle interferometry, that allows observing the rupture dynamics along the interface as well as the emitted elastic shear wavefield into the solid body. We compare the dynamics of propagating rupture for an homogeneous flat interface and for three cases of heterogeneous sliding surfaces: 1) an interface with a single point-like barrier made of a small rock pebble, 2) an interface with a single linear barrier that joins the edges of the faults in a direction perpendicular to slip 3) an interface with multiple barriers disposed on half of its surface area, creating an heterogeneous zone. We obtain experimental observations of dynamic effects that have been predicted by numerical dynamic rupture simulations and provide experimental observations of the following phenomena: a barrier can stop or delay the rupture propagation; a linear single barrier can change the rupture velocity, increasing or decreasing it; we observe transition from subshear to supershear propagation due to the linear barrier; a large heterogeneous area slows down the rupture propagation. We observe a strong variability of the rupture dynamics occurring for identical frictional conditions, that we impute to memory effects caused by the heterogeneity of the stress field due to both the loading conditions and the remaining stress field due to previous rupture events. These experiments therefore confirm previously reported numerical simulations of ruptures along heterogeneous interfaces. When comparing with natural observations or earthquake ruptures, our data provide some phenomenological insights to explain the complexity of the rupture history inferred from the pattern of seismic radiations.

Campillo, M.; Latour, S.; Voisin, C.; Catheline, S.; Renard, F.; Larose, E. F.

2013-12-01

314

Delayed diagnosis of a right-sided traumatic diaphragmatic rupture.  

PubMed

Right-sided traumatic diaphragmatic rupture in childhood is a very rare injury. Diaphragmatic rupture often manifests itself later, after an organ progressively herniates into the pleural cavity. When the patient is tubed, the ventilation pressure does not allow herniation of an organ, which occurs when the patient is ex-tubed. We present a patient with a delayed diagnose of right sided diaphragmatic rupture with a complicated post-operation state. PMID:24765402

Ku?era, Alexandr; Rygl, Michal; Snajdauf, Ji?í; Kavalcová, Lucie; Petr?, Ond?ej; Ritschelová, Vlasta; Kyn?l, Martin

2012-01-01

315

Mixed-Mode Interfacial Debonding Simulation in Single-Fiber Composite under a Transverse Load  

NASA Astrophysics Data System (ADS)

Due to the coupling between the opening and sliding modes of an interfacial crack between a fiber and matrix, measuring the individual values of the interfacial strengths, specifically the normal and shear strengths, is very difficult. A method based on comparison between experimental and numerical results is proposed and implemented for estimating the normal and shear strengths along such an interface. We numerically simulate mixed-mode interfacial debonding in a transverse tensile test for a single-fiber composite coupon. The interface is modeled using cohesive elements which are subjected to a quadratic failure criterion. Frictional effects are also included when the stress states are comprised of shear and compressive modes.

Koyanagi, Jun; Shah, Pranav D.; Kimura, Souta; Ha, Sung K.; Kawada, Hiroyuki

316

A Critique of a Phenomenological Fiber Breakage Model for Stress Rupture of Composite Materials  

NASA Technical Reports Server (NTRS)

Stress rupture is not a critical failure mode for most composite structures, but there are a few applications where it can be critical. One application where stress rupture can be a critical design issue is in Composite Overwrapped Pressure Vessels (COPV's), where the composite material is highly and uniformly loaded for long periods of time and where very high reliability is required. COPV's are normally required to be proof loaded before being put into service to insure strength, but it is feared that the proof load may cause damage that reduces the stress rupture reliability. Recently, a fiber breakage model was proposed specifically to estimate a reduced reliability due to proof loading. The fiber breakage model attempts to model physics believed to occur at the microscopic scale, but validation of the model has not occurred. In this paper, the fiber breakage model is re-derived while highlighting assumptions that were made during the derivation. Some of the assumptions are examined to assess their effect on the final predicted reliability.

Reeder, James R.

2010-01-01

317

Capturing Continental Rupture Processes in Afar  

NASA Astrophysics Data System (ADS)

Both continental and oceanic rifting processes are highly 3D, but the stability of the along-axis segmentation from rifting to breakup, and its relationship to seafloor spreading remains debated. Three-dimensional models of the interactions of faults and magmatism in time and space are in development, but modelling and observations suggest that magmatic segments may propagate and/or migrate during periods of magmatism. Our ability to discriminate between the various models in large part depends on the quality of data in the ocean-transition zone, or, observations from zones of incipient plate rupture. Largely 2D crustal-scale seismic data from magmatic passive margins reveal large magmatic additions to the crust, but the timing of this heat and mass transfer is weakly constrained. Thus, the lack of information on the across rift breadth of the deforming zone at rupture, and the relationship between the early rift segmentation and the seafloor spreading segmentation represent fundamental gaps in knowledge. Our study of Earth's youngest magmatic margin, the superbly exposed, tectonically active southern Red Sea, aims to answer the following questions: What are the geometry and kinematics of active fault systems across the 'passive margin' to zone of incipient plate rupture? What is the relationship between the initial border fault segmentation, and the breakup zone segmentation? What is the distribution of active deformation and magmatism, and how does it compare to time-averaged strain patterns? We integrate results of recent experiments that suggest widespread replacement of crust and mantle lithosphere beneath the 'passive' margin, and explain the ongoing seismic deformation as a consequence of bending stresses across the ocean-continent transition, with or without a dynamic component.

Ebinger, Cynthia; Belachew, Manahloh; Tepp, Gabrielle; Keir, Derek; Ayele, Atalay

2014-05-01

318

Migraine before rupture of intracranial aneurysms  

PubMed Central

Background 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. Methods In a prospective case–control study 199 consecutive patients with SIA (103 females and 96 males, mean age: 43.2 years) received a semistructured face to face interview focusing on past headaches. All were admitted to hospital mostly because of rupture (177) or for unruptured aneurysm (22). In parallel we interviewed 194 blood donors (86 females, 108 males, mean age: 38.4 years). Diagnoses were made according to the International Headache Society criteria. Aneurysms were diagnosed by conventional cerebral angiography. Results During the year before rupture, 124 (62.3%) had one or more types of headache. These headaches included: migraine without aura (MO): 78 (39.2%), migraine with aura (MA): 2 (1%), probable migraine (PM): 4 (2%), tension-type headache (TTH): 39 (19.6%), cluster headache (CH): 2 (1%), posttraumatic headaches (PH): 2 (1%). 1-year prevalence of headaches in controls was 32.5% (63 patients out of 194), they included: TTH: 45 (23.1%), MO: 17(8.8%), PH: 1(0.5%). Only the prevalence of MO was significantly higher in patients with SIA (OR 6.7, 95% CI 3.8-11.9, p?

2013-01-01

319

Forecasting the Rupture Directivity of Large Earthquakes  

NASA Astrophysics Data System (ADS)

Forecasting the rupture directivity of large earthquakes is an important problem in probabilistic seismic hazard analysis (PSHA), because directivity strongly influences ground motions. We cast this forecasting problem in terms of the conditional hypocenter distribution (CHD), defined to be the probability distribution of a hypocenter given the spatial distribution of fault slip (moment release). The simplest CHD is a uniform distribution for which the hypocenter probability density equals the moment-release probability density. We have compiled samples of CHDs from a global distribution of large earthquakes using three estimation methods: (a) location of hypocenters within the slip distribution from finite-fault inversions, (b) location of hypocenters within early aftershock distributions, and (c) direct inversion for the directivity parameter D, defined in terms of the degree-two polynomial moments of the source space-time function. The data from method (a) are statistically inconsistent with the uniform CHD suggested by McGuire et al. (2002) using method (c). Instead, the data indicate a 'centroid-biased' CHD, in which the expected distance between the hypocenter and the hypocentroid is less than that of a uniform CHD; i.e., the directivities inferred from finite-fault models appear to be closer to bilateral than predicted by the uniform CHD. One source of this discrepancy may be centroid bias in the second-order moments owing to poor localization of the slip in finite-fault inversions. We compare these observational results with CHDs computed from a large set of theoretical ruptures in the Southern California fault system produced by the Rate-State Quake simulator (RSQSim) of Dieterich and Richards-Dinger (2010) and discuss the implications for rupture dynamics and fault-zone heterogeneities.

Donovan, J. R.; Jordan, T. H.

2013-12-01

320

Mechanisms of plaque formation and rupture.  

PubMed

Atherosclerosis causes clinical disease through luminal narrowing or by precipitating thrombi that obstruct blood flow to the heart (coronary heart disease), brain (ischemic stroke), or lower extremities (peripheral vascular disease). The most common of these manifestations is coronary heart disease, including stable angina pectoris and the acute coronary syndromes. Atherosclerosis is a lipoprotein-driven disease that leads to plaque formation at specific sites of the arterial tree through intimal inflammation, necrosis, fibrosis, and calcification. After decades of indolent progression, such plaques may suddenly cause life-threatening coronary thrombosis presenting as an acute coronary syndrome. Most often, the culprit morphology is plaque rupture with exposure of highly thrombogenic, red cell-rich necrotic core material. The permissive structural requirement for this to occur is an extremely thin fibrous cap, and thus, ruptures occur mainly among lesions defined as thin-cap fibroatheromas. Also common are thrombi forming on lesions without rupture (plaque erosion), most often on pathological intimal thickening or fibroatheromas. However, the mechanisms involved in plaque erosion remain largely unknown, although coronary spasm is suspected. The calcified nodule has been suggested as a rare cause of coronary thrombosis in highly calcified and tortious arteries in older individuals. To characterize the severity and prognosis of plaques, several terms are used. Plaque burden denotes the extent of disease, whereas plaque activity is an ambiguous term, which may refer to one of several processes that characterize progression. Plaque vulnerability describes the short-term risk of precipitating symptomatic thrombosis. In this review, we discuss mechanisms of atherosclerotic plaque initiation and progression; how plaques suddenly precipitate life-threatening thrombi; and the concepts of plaque burden, activity, and vulnerability. PMID:24902970

Bentzon, Jacob Fog; Otsuka, Fumiyuki; Virmani, Renu; Falk, Erling

2014-06-01

321

Late sucessful treatment of splenic rupture in a haemophilic boy.  

PubMed Central

The recognition of traumatic splenic rupture in an 11-year-old severely affected haemophilic boy was delayed for over five weeks. Splenectomy was carried out successfully after the demonstration of splenic rupture by an isotope spleen scan. Splenic rupture is difficult to differentiate from more simple causes of retroperitoneal haematomata in haemophiliacs when there is no massive acute peritoneal bleeding, but it may be identified with isotopic spleen scans so long as the possibility of rupture is borne in mind. Images FIG 1 FIG 2 FIG 3 FIG 4

Gibson, B; Wright, F W; Rizza, C R; Dudley, N E

1976-01-01

322

Spontaneous diaphragmatic rupture: case report and literature review.  

PubMed

Spontaneous diaphragm rupture is extremely rare. Usually a diaphragm rupture is trauma induced. We describe a case of an 18-year old patient admitted 2 hours after onset, presenting severe epigastric and left sided chest pain without any trauma history. Upright chest x-ray revealed displaced stomach and colon into the left pleural cavity with a collapsed left lung. Surgery for a left-sided diaphragm rupture with stomach, spleen and colon splenic flexure herniation was undertaken. We present a brief review regarding the aetiology, diagnostic and treatment policy of spontaneous diaphragmatic rupture. PMID:23464778

Ghidirim, Gh; Mishin, I; Condratsky, E; Zastavnitsky, Gh

2013-01-01

323

Subcutaneous Peroneus Longus Tendon Rupture Associated with OS Peroneum Fracture  

PubMed Central

We report a rare case of subcutaneous peroneus longus tendon rupture associated with os peroneum fracture. Three dimensional computed tomographic scan was useful to understand this disorder. We treated the patient with excision of fractured os peroneum and tenodesis of the proximal stump of the ruptured peroneus longus tendon to the lateral aspect of the calcaneus. Key points In order to understand a rare case of subcutaneous peroneus longus tendon rupture associated with os peroneum fracture, three dimensional computed tomographic scan was useful. The patient was treated with excision of fractured os peroneum and tenodesis of the proximal stump of the ruptured peroneus longus tendon to the lateral aspect of the calcaneus.

Fujioka, Hiroyuki; Kokubu, Takeshi; Makino, Takeshi; Nagura, Issei; Maeda, Toshihisa; Kurosaka, Masahiro; Okuno, Hiroaki; Yamagiwa, Tokuyoshi; Tanaka, Juichi; Yoshiya, Shinichi

2009-01-01

324

Potential mechanism of annulus rupture during transcatheter aortic valve implantation.  

PubMed

Although annulus rupture is one of the most severe complications of transcatheter aortic valve implantation (TAVI), the incidence and mechanism of this complication remain unclear. Out of 387 consecutive TAVI cases in our institution, the incidence of annulus rupture was 1.0% (4/387). The first two patients died because of hemodynamic collapse due to tamponade on day 0. Both surviving patients had undergone preprocedural multidetector computed tomography which revealed large calcifications in the epicardial fat part of the aortic annulus. In both cases, annulus rupture occurred after deployment of a balloon expandable valve suggesting that mechanical compression of this "vulnerable area" by calcification may cause annulus rupture. PMID:22718400

Hayashida, Kentaro; Bouvier, Erik; Lefèvre, Thierry; Hovasse, Thomas; Morice, Marie-Claude; Chevalier, Bernard; Romano, Mauro; Garot, Philippe; Farge, Arnaud; Donzeau-Gouge, Patrick; Cormier, Bertrand

2013-11-01

325

Delayed presentation of a traumatic diaphragmatic rupture with intrapericardial herniation.  

PubMed

Thoracic and abdominal blunt traumas are the major causes of diaphragmatic rupture. These ruptures may be recognized at the time of the initial trauma, but are diagnosed months or even years later during the workup for related symptoms. We present herein a patient who suffered from abdominal pain and dyspnea years after a motor vehicle accident. A chest computed tomography (CT) demonstrated diaphragmatic rupture with intrapericardial herniation of intraabdominal organs. Exploratory laparotomy confirmed the diagnosis. In this report, we describe our management of this unusual diaphragmatic rupture. PMID:21258833

Cipe, G; Genç, V; Uzun, C; Atasoy, C; Erkek, B

2012-08-01

326

Estimating Out-of-Plane Strength of Cracked Masonry Infills.  

National Technical Information Service (NTIS)

The primary objective of the research project was to determine the transverse (out-of-plane) seismic strength of unreinforced masonry infill panels that have been cracked with in-plane lateral forces. The goal of the research was to develop a simple metho...

D. Abrams D. Shapiro J. Uzarski M. Webster R. Angel

1994-01-01

327

Surface roughness and bond strength of enamel to composite  

Microsoft Academic Search

Objectives: The aim of the study was to assess the influence of pretreating enamel by different rotary instruments on shear-bond strength of composite to enamel after the acid etch technique.Methods: Ninety human enamel specimens with transversely and longitudinally sectioned prisms were ground flat, and half of the enamel area of each specimen was prepared with one of the eight different

M Jung; L. O Wehlen; J Klimek

1999-01-01

328

Noninvasive Vascular Displacement Estimation for Relative Elastic Modulus Reconstruction in Transversal Imaging Planes  

PubMed Central

Atherosclerotic plaque rupture can initiate stroke or myocardial infarction. Lipid-rich plaques with thin fibrous caps have a higher risk to rupture than fibrotic plaques. Elastic moduli differ for lipid-rich and fibrous tissue and can be reconstructed using tissue displacements estimated from intravascular ultrasound radiofrequency (RF) data acquisitions. This study investigated if modulus reconstruction is possible for noninvasive RF acquisitions of vessels in transverse imaging planes using an iterative 2D cross-correlation based displacement estimation algorithm. Furthermore, since it is known that displacements can be improved by compounding of displacements estimated at various beam steering angles, we compared the performance of the modulus reconstruction with and without compounding. For the comparison, simulated and experimental RF data were generated of various vessel-mimicking phantoms. Reconstruction errors were less than 10%, which seems adequate for distinguishing lipid-rich from fibrous tissue. Compounding outperformed single-angle reconstruction: the interquartile range of the reconstructed moduli for the various homogeneous phantom layers was approximately two times smaller. Additionally, the estimated lateral displacements were a factor of 2–3 better matched to the displacements corresponding to the reconstructed modulus distribution. Thus, noninvasive elastic modulus reconstruction is possible for transverse vessel cross sections using this cross-correlation method and is more accurate with compounding.

Hansen, Hendrik H.G.; Richards, Michael S.; Doyley, Marvin M.; de Korte, Chris L.

2013-01-01

329

Strength Coefficient of Materials.  

National Technical Information Service (NTIS)

South Dakota's, previously conducted, Flexible Pavement Study indicated a relationship between Strength and Effective Thickness. It was apparent that a simple slope formula used for any two points on the curve produced strength coefficients. The slope of ...

R. A. Crawford

1971-01-01

330

Measurement of laser-ion guiding channel strength  

SciTech Connect

The Advanced Test Accelerator (ATA) beam is guided in a low density ion channel produced in benzene gas by a KrF laser. The strength of the ion channel has been measured by deflecting the electron beam in a steady transverse magnetic field. After emerging from the magnetic field, the beam oscillates transversely inside the channel with a few mm amplitude. The transverse position of the beam is measured at many positions using the wall current monitors. The wavelength of the oscillation is measured from a plot of transverse position vs propagation distance. With a 0.5 J laser pulse and 4 x 10/sup -4/ Torr benzene pressure the wavelength was 1 m corresponding to 90 esu/cm/sup 3/ with ..gamma.. = 84.

Lauer, E.J.; Caporaso, G.J.; Chong, Y.P.; Prono, D.S.; Rainer, F.; Struve, K.W.; Weir, J.T.

1986-01-01

331

Semicircular bend testing with split Hopkinson pressure bar for measuring dynamic tensile strength of brittle solids  

Microsoft Academic Search

We propose and validate an indirect tensile testing method to measure the dynamic tensile strength of rocks and other brittle solids: semicircular bend (SCB) testing with a modified split Hopkinson pressure bar (SHPB) system. A strain gauge is mounted near the failure spot on the specimen to determine the rupture time. The momentum trap technique is utilized to ensure single

F. Dai; K. Xia; S. N. Luo

2008-01-01

332

Visualization of transverse annular jets  

NASA Astrophysics Data System (ADS)

Transverse injection of fluid into an annular jet is a mechanism resulting in good mixing and is therefore utilized in engineering applications such as pintle rocket engines. Vigorous mixing occurs between the two jets. However, much of what we know about the flow behavior of such devices has been learned empirically with very limited studies exploring the fluid dynamics. The geometry under investigation is an axisymmetric radial jet of variable width impinging a fixed annular jet. The main capability of the current facility is to reproduce start-up and quasi-steady flow conditions through the use of a fast acting valve which opens a pressurized reservoir. The flow is then observed using a schlieren system which shows the shock wave from the start-up and the subsequent mixing between the jets. The main parameters under investigation were the reservoir pressure and the area ratio between the axial and radial jet. The effect of these parameters on the qualitative flow behavior is discussed. This effort was carried out in conjunction with modeling efforts at JPL.

Boettcher, Philipp; Mikellides, Ioannis G.; Vaughan, David A.; Shephard, Joseph E.; Damazo, Jason

2009-11-01

333

Dynamic Tension Spectroscopy and Strength of Biomembranes  

PubMed Central

Rupturing fluid membrane vesicles with a steady ramp of micropipette suction produces a distribution of breakage tensions governed by the kinetic process of membrane failure. When plotted as a function of log(tension loading rate), the locations of distribution peaks define a dynamic tension spectrum with distinct regimes that reflect passage of prominent energy barriers along the kinetic pathway. Using tests on five types of giant phosphatidylcholine lipid vesicles over loading rates(tension/time) from 0.01–100 mN/m/s, we show that the kinetic process of membrane breakage can be modeled by a causal sequence of two thermally-activated transitions. At fast loading rates, a steep linear regime appears in each spectrum which implies that membrane failure starts with nucleation of a rare precursor defect. The slope and projected intercept of this regime are set by defect size and frequency of spontaneous formation, respectively. But at slow loading rates, each spectrum crosses over to a shallow-curved regime where rupture tension changes weakly with rate. This regime is predicted by the classical cavitation theory for opening an unstable hole in a two-dimensional film within the lifetime of the defect state. Under slow loading, membrane edge energy and the frequency scale for thermal fluctuations in hole size are the principal factors that govern the level of tension at failure. To critically test the model and obtain the parameters governing the rates of transition under stress, distributions of rupture tension were computed and matched to the measured histograms through solution of the kinetic master (Markov) equations for defect formation and annihilation or evolution to an unstable hole under a ramp of tension. As key predictors of membrane strength, the results for spontaneous frequencies of defect formation and hole edge energies were found to correlate with membrane thicknesses and elastic bending moduli, respectively.

Evans, Evan; Heinrich, Volkmar; Ludwig, Florian; Rawicz, Wieslawa

2003-01-01

334

Evolution of the helicity and transversity Transverse-Momentum-Dependent parton distributions  

SciTech Connect

We examine the QCD evolution of the helicity and transversity parton distribution functions when including also their dependence on transverse momentum. Using an appropriate definition of these polarized transverse momentum distributions (TMDs), we describe their dependence on the factorization scale and rapidity cutoff, which is essential for phenomenological applications.

Prokudin, Alexei [JLAB; Bacchetta, Alessandro [INFN-PAVIA

2013-07-01

335

Evolution of the helicity and transversity Transverse-Momentum-Dependent parton distributions  

SciTech Connect

We examine the QCD evolution of the helicity and transversity parton distribution functions when including also their dependence on transverse momentum. Using an appropriate definition of these polarized transverse momentum distributions (TMDs), we describe their dependence on the factorization scale and rapidity cutoff, which is essential for phenomenological applications.

Prokudin, Alexey [JLAB; Bacchetta, Alessandro [INFN-PAVIA

2013-10-01

336

Transverse Engine (a novel piston engine concept)  

Microsoft Academic Search

Transverse Engine is a novel piston engine concept. As the name implies, the cylinder block is transverse to the output shaft. Basically, the engine has a set of four cylinders. Any number of sets of four cylinders can be arranged parallel to each other or radial to the output shaft. The linkage transmitting power from the reciprocating pistons to the

1984-01-01

337

DOUBLE TRANSVERSE SPIN ASYMMETRIES AT NLO.  

SciTech Connect

We report on a next-to-leading order QCD calculation of the cross section and the spin asymmetry for isolated large-p{sub T} prompt photon production in collisions of transversely polarized protons. Corresponding measurements may be used at RHIC to determine the transversity parton distributions of the proton.

MUKHERJEE,A.STRATMANN,M.VOGELSANG,W.

2003-09-03

338

Transverse loads on a yawed projectile  

Microsoft Academic Search

Yaw has been known to greatly influence the penetration performance of long-rod projectiles. Experiments have shown that even small angles of yaw can significantly degrade performance. We show that a critical feature of a yawed impact is the transverse load on the penetrator. Transverse loads tend to decrease the misalignment of rod axis and velocity vector. We use classical cavity

Stephan J. Bless; Sikhanda Satapathy; Michael J. Normandia

1999-01-01

339

Transverse instability at the recycler ring  

SciTech Connect

Sporadic transverse instabilities have been observed at the Fermilab Recycler Ring leading to increase in transverse emittances and beam loss. The driving source of these instabilities has been attributed to the resistive-wall impedance with space-charge playing an important role in suppressing Landau damping. Growth rates of the instabilities are computed. Remaining problems are discussed.

Ng, K.Y.; /Fermilab

2004-10-01

340

Foliations Transverse to Fibers of Seifert Manifoldsy  

Microsoft Academic Search

In this paper we prove the conjecture of Jankins and Neumann (JN2) about rotation numbers of products of circle homeomorphisms, which together with other results of (EHN) and (JN2) (mentioned be- low) implies that a Seifert manifold admits foliations transverse to itsbers only if it admits such foliations with a projective transverse structure. 1. History

Ramin Naimi

1994-01-01

341

Transverse Mercator Projection Via Elliptic Integrals  

NASA Technical Reports Server (NTRS)

Improved method of construction of U.S. Army's universal transverse Mercator grid system based on Gauss-Kruger transverse Mercator projection and on use of elliptic integrals of second kind. Method can be used to map entire northern or southern hemisphere with respect to single principal meridian.

Wallis, David E.

1992-01-01

342

The Repetition of Large-Earthquake Ruptures  

NASA Astrophysics Data System (ADS)

This survey of well-documented repeated fault rupture confirms that some faults have exhibited a ``characteristic'' behavior during repeated large earthquakes--that is, the magnitude, distribution, and style of slip on the fault has repeated during two or more consecutive events. In two cases faults exhibit slip functions that vary little from earthquake to earthquake. In one other well-documented case, however, fault lengths contrast markedly for two consecutive ruptures, but the amount of offset at individual sites was similar. Adjacent individual patches, 10 km or more in length, failed singly during one event and in tandem during the other. More complex cases of repetition may also represent the failure of several distinct patches. The faults of the 1992 Landers earthquake provide an instructive example of such complexity. Together, these examples suggest that large earthquakes commonly result from the failure of one or more patches, each characterized by a slip function that is roughly invariant through consecutive earthquake cycles. The persistence of these slip-patches through two or more large earthquakes indicates that some quasi-invariant physical property controls the pattern and magnitude of slip. These data seem incompatible with theoretical models that produce slip distributions that are highly variable in consecutive large events.

Sieh, Kerry

1996-04-01

343

TMI-2 lower head creep rupture analysis  

SciTech Connect

The TMI-2 accident resulted in approximately 40% of the reactor's core melting and collecting on the lower head of the reactor pressure vessel. The severity of the accident has raised questions about the margin of safety against rupture of the lower head in this accident since all evidence seems to indicate no major breach of the vessel occurred. Scoping heat transfer analyses of the relocated core debris and lower head have been made based upon assumed core melting scenarios and core material debris formations while in contact with the lower head. This report describes the structural finite element creep rupture analysis of the lower head using a temperature transient judged most likely to challenge the structural capacity of the vessel. This evaluation of vessel response to this transient has provided insight into the creep mechanisms of the vessel wall, a realistic mode of failure, and a means by which margin to failure can be evaluated once examination provides estimated maximum wall temperatures. Suggestions for more extensive research in this area are also provided. 6 refs., 15 figs.

Thinnes, G.L.

1988-08-01

344

[Aneurysmal rupture complicating aortitis: A case report].  

PubMed

Tropical aortitis is a rare and poorly described aortic disease, sometimes confounded with Takayasu's disease, mainly in people from Africa. In this case report, the panaortic aneurysmal disease in a young woman from Haiti, first diagnosed after a work-up on renovascular hypertension, would appear to approach this particular arterial disease with no clinical, radiological or biological argument for an infectious etiology. The initially suspected diagnosis of Takayasu's disease had to be rethought because of the presence of several saccular aneurysms extending from the aortic arch to the infrarenal aorta, rarely described in Takayasu's aortitis. Expert opinions from vascular surgeons and clinicians tagged this aortic disease as similar to tropical aortitis which remained asymptomatic for more than a decade. Hypertension was managed with successful balloon angioplasty of the left renal artery stenosis and anti-hypertensive combination therapy. Surgical management of the extended aortic aneurysms was not proposed because of the stability and asymptomatic nature of the aneurysmal disease and the high risk of surgical morbidity and mortality. More than ten years after diagnosis, the course was marked with inaugural and sudden-onset chest pain concomitant with contained rupture of the descending thoracic aortic aneurysm. This case report underlines the persistent risk of aneurysmal rupture and the importance of an anatomopathological study for the diagnosis of complex aortic disease. PMID:24637031

Yannoutsos, A; Mercier, O; Messas, E; Safar, M E; Blacher, J

2014-05-01

345

[Spontaneous splenic rupture in acute malaria tropica].  

PubMed

A 44-year-old man developed bouts of fever (up to 40 degrees C) seven days after returning from a holiday in Kenya. Malaria prophylaxis with chloroquine had been correctly undertaken. Concentrations of lactate dehydrogenase and total bilirubin were raised (493 U/l and 3.55 mg/dl, respectively). Blood smear revealed the ring forms of Plasmodium falciparum. Thereupon the patient was given mefloquine in decreasing doses (750/500/250 mg) at intervals of 8 hours. The following night he had a circulatory collapse and complained of pain on pressure, especially in the left upper abdomen. Abdominal sonography showed a slightly enlarged spherical spleen with an echo-poor band and fluid collection in the rectovesicular pouch, indicating rupture of the spleen. A splenectomy was performed. Subsequently the number of malaria organisms in the blood smear gradually fell and signs of haemolysis disappeared. Splenic rupture is a very rare complication of acute malaria. It is presumably caused by marked stasis in the splenic sinuses with deformed parasite-containing red blood cells. PMID:1597109

Falk, S; Protz, H; Köbrich, U; Stutte, H J

1992-05-29

346

Rupture of the myocardium. Occurrence and risk factors.  

PubMed Central

The occurrence of myocardial rupture was studied in a well defined unselected population of patients with acute myocardial infarction, and the group of patients who died of rupture of the heart were compared with two control groups. Of a total of 3960 patients, 1746 (44%) fulfilled the diagnostic criteria for acute myocardial infarction. Rupture was defined solely on the basis of the presence of a pathological passage through part of the myocardium, either the free wall of the left ventricle or the septum, found at necropsy or during operation. Two controls were selected for each patient and matched for age and sex, one (control group A) with acute myocardial infarction having died in hospital but not of rupture (non-rupture cardiac death) and one (control group B) with acute myocardial infarction having survived the hospital stay. Necropsy was performed in 75% of all fatal cases with acute myocardial infarction. The total hospital mortality was 19%, the highest mortality being among women over 70 years (29%). Ruptures (n = 56) were found in 17% of the hospital deaths, or 3.2% of all cases of acute myocardial infarction. Women aged less than 70 had the highest incidence of rupture, 42% of deaths being due to rupture. The mean age for patients with rupture and controls was 70.5 years. The median time after admission to death was approximately 50 hours for patients and control group A. Thirty per cent of the patients with rupture occurred within 24 hours of the initial symptoms occurring. Angina and previous acute myocardial infarction were more common among control group A. Patients with rupture and control group B were mostly relatively free of previous cardiovascular or other diseases (chronic angina pectoris ( > 2 months) and previous myocardial infarction). Sustained hypertension during admission to the coronary care unit was more common in patients than in control group A. Hypotension and shock were more common among control group A. Most (79%) of the patients who subsequently ruptured did not receive any corticosteroids at all during the hospital stay. Severe heart failure and antiarrhythmic treatment were more uncommon among patients than among control group A. Patients with rupture received analgesics approximately three times a day throughout their stay. Control group B received analgesics mostly during the first 24 hours. Thus female patients, patients with first infarcts, and patients with sustained chest pain should be investigated for the possibility of rupture. As many as one third (32%) of ruptures may be subacute, and therefore time is available for diagnosis and surgery.

Dellborg, M; Held, P; Swedberg, K; Vedin, A

1985-01-01

347

How is a stick slip rupture initiated?  

NASA Astrophysics Data System (ADS)

We investigated the initiation process of stick slip events that occurred during large scale rock friction experiments conducted on the large scale shaking table at NIED (Fukuyama et al., 2012, AGU Fall meeting). We used a pair of Indian gabbro rock samples stacked vertically and applied normal and shear forces. The sliding area between the samples is 1.5m in length and 0.1m in width. We conducted a sequence of experiments using the same rock sample, and before each experiment we removed gouge particles created during the previous experiment by a brush and a cleaner. Here, we show the experiments under constant slip velocity of 0.1mm/s with constant normal stress of 2.7MPa (LB04-003) or 6.7MPa (LB04-005); the final displacement reached 0.04m. We used 44 acoustic sensors (PZT, vertical mode, 0.5MHz resonance frequency), 32 2-comp strain gouges (SGs) for shear strain and 16 1-comp SGs for normal strain measurements, with 48 0.5MHz dynamic SG amplifiers. We also used a 2MN load cell for shear force measurement and three 0.4MN load cells for vertical forces. Data are recorded continuously at an interval of 10MHz for PZT and 1MHz for other sensors. Just after the shear force applied, many stick slip events (SEs) occurred at an interval of a few seconds. By looking carefully at the PZT and SG array data during an SE, we found that one SE consists of many micro stick slip events (MSEs), which can be grouped into two (the former and the latter). These two groups correspond to the acceleration and deceleration stage of the SE. In LB04-005 (6.7MPa normal stress), a clear nucleation phase can be detected that initiated at a narrow area, propagate slowly (~20m/s) and accelerated. Then, a seismic rupture started to propagate at a velocity of ~3km/s (subshear) or ~6.5km/s (supershear). Detailed features are shown in Mizoguchi et al. (this meeting). It should be noted that this seismic rupture initiated at a narrow area inside the nucleation zone and sometimes after a certain amount of time; it does not seem a smooth transition process from the acceleration to the seismic rupture as proposed in Ohnaka and Shen (1999, JGR). In contrast, under low normal stress case (LB04-003, 2.7MPa), there were no visible nucleation phases but a sequence of foreshocks was observed, which was not dominant in LB04-005. The foreshock slip area was typically around 10cm long. Again, we could not see any visible correlation between the location and preceding time of foreshocks and that of seismic rupture initiation. By looking at the fault surface topography that was recorded as photograph images before and after the experiment, in the nucleation zone, grooves are not developed, while outside the nucleation area, grooves are well developed. Grooves are caused by the creation of gouge particles during the sliding. It could be interesting to note that outside the groove, the sliding surface looks very smooth and shiny, indicating that this area was polished but did not create gouge particles. Therefore, we might speculate that this shiny fault area is responsible for the initiation phase and when the stress state becomes critical, seismic rupture starts around one of the grooves. And in LB04-003, the shiny area might not support the shear stress so that the foreshock releases the strain around the grooves.

Fukuyama, E.; Mizoguchi, K.; Yamashita, F.; Kawakata, H.; Takizawa, S.

2013-12-01

348

Study of Interfacial Stress Distribution in SiC Fiber Reinforced Titanium Matrix Composites on Transverse Tensile Tests  

NASA Astrophysics Data System (ADS)

A combination of the transverse tensile test and the unilaterally coupled finite element method was used to evaluate the interfacial normal bond strength and stress distribution of titanium matrix composites (TMCs). In addition, in order to identify the interface shear failure mode of TMCs under transverse loading, both the push-out test and the finite element method have been developed to characterize the interfacial shear strength of TMCs, which is the interfacial shear failure criterion. This article studies the results of the experiments, which suggested that the interfacial normal bond and shear strength of SiCf/Ti-6Al-4V were 300 and 350 MPa, respectively, and the interface failure mode of TMCs under the transverse tensile test was radial failure rather than shear failure. Moreover, the effect of residual stress on the radial stress is also discussed in detail in this article.

Yanfang, Xu; Tiexiong, Su; Meini, Yuan

2012-11-01

349

Strength Modeling Report  

NASA Technical Reports Server (NTRS)

Strength modeling is a complex and multi-dimensional issue. There are numerous parameters to the problem of characterizing human strength, most notably: (1) position and orientation of body joints; (2) isometric versus dynamic strength; (3) effector force versus joint torque; (4) instantaneous versus steady force; (5) active force versus reactive force; (6) presence or absence of gravity; (7) body somatotype and composition; (8) body (segment) masses; (9) muscle group envolvement; (10) muscle size; (11) fatigue; and (12) practice (training) or familiarity. In surveying the available literature on strength measurement and modeling an attempt was made to examine as many of these parameters as possible. The conclusions reached at this point toward the feasibility of implementing computationally reasonable human strength models. The assessment of accuracy of any model against a specific individual, however, will probably not be possible on any realistic scale. Taken statistically, strength modeling may be an effective tool for general questions of task feasibility and strength requirements.

Badler, N. I.; Lee, P.; Wong, S.

1985-01-01

350

Posttraumatic free intraperitoneal rupture of liver cystic echinococcosis: a case series and review of literature  

Microsoft Academic Search

BackgroundA serious complication of cystic echinococcus (CE) is the rupture of the cysts. Free intra-abdominal rupture occurs in approximately 3.2% of all cases. Posttraumatic rupture of liver CE is very rare.

Gurkan Ozturk; Bulent Aydinli; M. Ilhan Yildirgan; Mahmut Basoglu; S. Selcuk Atamanalp; K. Yalcin Polat; Fatih Alper; Bulent Guvendi; M. Nuran Akcay; Durkaya Oren

2007-01-01

351

Preliminary evaluation of tensile and stress-rupture behavior of W + 24 at. pct Re + 0.4 at. pct HfC wire  

NASA Technical Reports Server (NTRS)

Results are presented of an evaluation of tensile properties and stress-rupture bahavior of a small-diameter W24ReHfC (W-24Re-0.4(HfC)) wire, which is considered to be an excellent reinforcing fiber candidate for a variety of metal-matrix composites. The results were compared to data of Petrasek (1972) on W4ReHfC (W-4Re-0.4(HfC)) wire. It was found that the room-temperature (RT) tensile strength of the W24ReHfC wire was about 3250 MPa, higher than that of the W4ReHfC (3160 MPa) and WHfC (2250 MPa) wires. Above 1366 K, the W4ReHfC wire had both a greater tensile strength and the stress rupture strength than the W24ReHfC wire.

Yun, H. M.

1993-01-01

352

Endovascular repair of spontaneous or traumatic iliac vein rupture.  

PubMed

Spontaneous rupture of the iliac vein and rupture resulting from blunt trauma are both very unusual. Herein one case of each are reported and were managed by emergent endovascular repair with use of covered stents. Favorable outcomes were achieved in both cases. PMID:15297589

Zieber, Steven R; Mustert, Bryan R; Knox, Michael F; Fedeson, Brian C

2004-08-01

353

Liposome rupture and contents release over coplanar microelectrode arrays  

Microsoft Academic Search

The vulnerability of vesicles to electroporation and rupture by externally applied electric fields, combined with the ability of dielectrophoresis and\\/or AC electroosmosis to manipulate suspended vesicles over micropatterned electrodes suggests new techniques to electrically trigger localized chemical reactions at predetermined positions in microfluidic devices. The electric field conditions needed to rupture giant unilamellar phospholipid vesicles were determined as a function

Jit Kang Lim; Hao Zhou; Robert D. Tilton

2009-01-01

354

Traumatic rupture of the aortic isthmus: An emergency?  

Microsoft Academic Search

The objectives of this study were to explore the hypotheses that: (1) patients with traumatic rupture of the aortic isthmus (TRA) who have not exsanguinated into the pleural cavity upon hospital presentation are unilikely to develop rupture of the hematoma during the time necessary to investigate all injuries and attend to those of more immediate danger; and (2) appropriate medical

James W. Pate; Timothy C. Fabian; William Walker

1995-01-01

355

Comparing Two Methods of Identifying Alliance Rupture Events.  

PubMed

This study compared two methods of detecting ruptures in therapy sessions, a procedure based on a self-report measure, the Working Alliance Inventory (WAI), and an observational Rupture Resolution Rating System (3RS). We anticipated that the 3RS would detect more ruptures than the WAI. We examined the longitudinal data of 38 patient-therapist dyads in a cognitive-behavioral therapy condition. The sample included cases that did not complete treatment (dropped cases) as well as good-outcome and poor-outcome cases. At the end of each session, patients completed the WAI self-report questionnaire. Six judges were trained to observe and detect the occurrence of ruptures, and then rated 201 videotaped sessions. Longitudinal statistical models were applied to the data retrieved from the WAI questionnaires completed by patients. We found discrepancies in the ability of the two methods to detect rupture events with the observational 3RS detecting more ruptures than the WAI. Thus, the use of observational systems for the detection of alliance ruptures is crucial for effectively assessing the quality of the therapeutic alliance over the course of treatment. Furthermore, observational systems proven to detect ruptures can be used to improve clinical practice and training of new clinicians. (PsycINFO Database Record (c) 2013 APA, all rights reserved). PMID:23668940

Coutinho, Joana; Ribeiro, Eugénia; Sousa, Inês; Safran, Jeremy D

2013-05-13

356

Delayed rupture of renal artery after renal percutaneous transluminal angioplasty  

SciTech Connect

Two cases are reported in which rupture of the renal artery occurred many hours after renal percutaneous transluminal angioplasty. Delayed rupture can be recognized by the angiographic appearance and by the presence of persistent flank pain. The typical angiographic finding is a poorly defined zone of contrast medium at the site of perforation.

Puijlaert, C.B.A.J.; Mali, W.P.; Rosenbusch, G.; van Straalen, A.M.; Klinge, J.; Feldberg, M.A.M.

1986-06-01

357

Tracheal rupture in a cat: Diagnosis by computed tomography  

PubMed Central

A cat was presented with a history of worsening generalized subcutaneous emphysema following dental prophylaxis. Tentative diagnosis of tracheal rupture was made. The location and extent of the tear was confirmed with the help of computed tomography. This is the 1st computed tomographic description of tracheal rupture in the veterinary literature.

Bhandal, Jitender; Kuzma, Alan

2008-01-01

358

Rupture of the stomach following mouth-to-mouth respiration  

PubMed Central

Successful repair and survival after rupture of the stomach in a patient who received mouth-to-mouth respiration is presented. We were able to find only one report in the literature where rupture of the stomach occurred following this manoeuvre—the patient did not survive. The possible aetiological factors and measures designed to avoid this complication are discussed. ImagesFig. 1

Solowiejczyk, M.; Wapnick, S.; Koren, E.; Mandelbaum, J.

1974-01-01

359

Spontaneous splenic rupture caused by Babesia microti infection.  

PubMed

Babesiosis has not been previously associated with spontaneous splenic rupture. We describe an otherwise healthy 61-year-old man with symptomatic babesiosis whose spleen ruptured during hospitalization. Although this complication is rare, practitioners who commonly treat patients with babesiosis should be aware of its potential occurrence. PMID:18419430

Kuwayama, David P; Briones, Renato J

2008-05-01

360

Traumatic rupture of right hemidiaphragm in a child.  

PubMed

Acute right-sided diaphragmatic ruptures are rare in children. We report a case of traumatic right-sided diaphragmatic rupture in a child that was managed by delayed repair. The clinical presentation and importance of making an accurate diagnosis and confirmation of any associated visceral injury before definitive surgery is highlighted. PMID:17160782

Antao, B; Lansdale, N; Shawis, R

2006-10-01

361

Vaginal birth after cesarean and uterine rupture rates in California  

Microsoft Academic Search

Objective: To describe attempted and successful vaginal birth after cesarean (VBAC) rates and uterine rupture rates for women with and without prior cesareans, and compare delivery outcomes in hospitals with different attempted VBAC rates.Methods: We used California hospital discharge summary data for 1995 to calculate attempted and successful VBAC rates and uterine rupture rates. We used multivariate logistic regression models

Kimberly D Gregory; Lisa M Korst; Patricia Cane; Lawrence D Platt; Katherine Kahn

1999-01-01

362

Computation of initial stage of RBMK reactor fuel channel vessel rupture  

SciTech Connect

Objective of this work is estimation of temperature and time characteristics for rupture of the zirconium pipe which is the RBMK reactor fuel channel (FC) vessel under emergencies. As an emergency the zirconium pipe temperature rise process is considered which results in loss of pipe material strength properties and pipe rupture under the action of internal pressure P=80MPa. The work was carried out under Task Order 007 of University of California - VNIIEF Subcontract No. 0002P0004-95. The problem formulation is stated in Protocol (Task 3, Appendix 3) of the Russian-American Workshop which was held in December, 1994 in Los Alamos. Physical-mechanical and geometry characteristics of structure elements (FC vessel with graphite ring and graphite slug) are presented by NIKIET. The temperature mode of the structure is taken in conformity with the NIKIET data obtained with the RELAP5/MOD3 code. Numerical simulation of structure element behavior in an emergency is performed using the DRAKON program comlex oriented to solving strength problems for complex spatial structures at intense dynamic loading. The {open_quotes}DRAKON{close_quotes} program complex is described and compared with similar western codes in its capabilities.

Pevnitsky, A.V.; Solovyev, V.P.; Abakumov, A.I. [and others

1995-12-31

363

Single-incision repair of acute distal biceps ruptures by use of suture anchors.  

PubMed

The purpose of this study is to report the results of a single limited-incision technique for repair of acute distal biceps ruptures by use of suture anchors. Sixty consecutive patients underwent distal biceps repair after an acute rupture between January 1997 and January 2001 by use of a limited antecubital incision and suture anchors. Fifty-three patients could be evaluated at a mean follow-up of 38.1 months. A limited transverse incision was made in the antecubital fossa. The retracted biceps tendon end was identified, retrieved, and lightly debrided. Two suture anchors were placed in the radial tuberosity, and the tendon was reapproximated. Final follow-up consisted of physical examination, radiographs, and Andrews-Carson elbow score tabulations. According to the Andrews-Carson scores, there were 46 excellent and 7 good results. In 2 patients, heterotopic ossification developed that resulted in a mild loss of forearm rotation and mild pain. In 1 patient, a temporary radial nerve palsy developed, which resolved completely within 8 weeks. Repair of acute distal biceps tears via a limited antecubital incision and suture anchors is a safe, effective technique. PMID:16963286

John, Chris K; Field, Larry D; Weiss, Kenneth S; Savoie, Felix H

2007-01-01

364

Prevalence of silicone breast implant rupture among Danish women.  

PubMed

The durability of silicone gel-filled breast implants is of concern, but there are few epidemiological studies on this issue. To date, most of the relevant findings are derived from studies of explantation, which suffer from bias by including women with symptoms or concerns about their implants. As part of a long-term magnetic resonance imaging study of the incidence of rupture, this study involved 271 women with 533 cosmetic breast implants who were randomly selected from among women who underwent cosmetic breast implantation from 1973 through 1997 at one public and three private plastic-surgery clinics in Denmark. The prevalence of rupture was determined from the first magnetic resonance screening. The images were evaluated by four independent readers, using a standardized, validated form. The outcomes under study were rupture, possible rupture, and intact implant. Ruptures were categorized as intracapsular or extracapsular. Overall, 26 percent of implants in 36 percent of the women examined were found to be ruptured, and an additional 6 percent were possibly ruptured. Of the ruptured implants, 22 percent were extracapsular. In multiple regression analyses, age of implant was significantly associated with rupture among second- and third-generation implants, with a 12-fold increased prevalence odds ratio for rupture of implants that were between 16 and 20 years of age, compared with implants between 3 and 5 years of age. Surgitek implants (Medical Engineering Corporation, Racine, Wis.) had a significantly increased prevalence odds ratio of 2.6 for rupture, compared with the reference implants. No significant association was found with the position (subglandular or submuscular) or the type of implant (single- or double-lumen). Extracapsular ruptures were significantly associated with a history of closed capsulotomy (p = 0.001). In the future, the authors plan to examine the women in their cohort with a second magnetic resonance imaging scan to establish the incidence of rupture, a parameter unknown to date in the literature, and to further characterize those factors associated with the actual risk of rupture. PMID:11547138

Hölmich, L R; Kjøller, K; Vejborg, I; Conrad, C; Sletting, S; McLaughlin, J K; Fryzek, J; Breiting, V; Jørgensen, A; Olsen, J H

2001-09-15

365

Do All Large Strike-slip Earthquakes Have Supershear Ruptures?  

NASA Astrophysics Data System (ADS)

Studying the rupture speeds of earthquakes is of broad interesting for earthquake research because it has a large effect on the strong near-field shaking that causes damage during earthquakes. Also rupture speed is a key observation for understanding the controlling stresses and friction during an earthquake, yet the speed and its variations are usually difficult to determine. Using only far-field seismic waveforms, which is the only data available for many large earthquakes, there are problems for estimating the rupture speed with standard waveform inversions, due to trade-off between the rupture speed and the slip location. Here we applied a back projection method to estimate the rupture speeds of Mw ? 7.5 strike-slip earthquakes since 2001 which could be analyzed using Hi-net in Japan. We found that all events had very fast average rupture speeds of 3.0-6.0 km/s, which are near or greater than the local shear wave velocity (supershear). These values are faster than for thrust and normal faulting earthquakes that generally rupture with speeds of 1.0-3.0 km/s. Considering the depth-dependent shear-wave velocity, the average propagation speeds for all of the strike-slip events are closer to or greater than the shear wave velocity (Figure 1). For large strike-slip events, transition from subshear to supershear usually occurs within distances of 15 to 30 km from the initiation, which is probably the reason for the scarcity of observed supershear earthquakes for smaller magnitudes. Earthquakes with supershear ruptures can cause more damage than events with subshear ruptures because of the concentration of energy in the forward direction of the rupture. Numerical modeling shows strong focusing and other effects of energy at the rupture front which can intensify the ground motions. A recent example is the April 13, 2010 Qinghai, China earthquake (Mw 6.9), where a moderate-size event caused extensive damage in the Yushu region at the southeastern end of the fault. Careful evaluation of long and straight strike-slip faults should be emphasized for predicting strong ground motions due to supershear rupture. a: Average rupture speeds for Mw ? 7.5 strike-slip earthquakes. For comparison, dip-slip earthquakes are also shown. The blue dashed line presents the S wave velocity model of PREM for comparison. b: Rupture velocities are shown as ratio to the local S wave velocity, as a function of depth.

Wang, D.; Mori, J. J.; Koketsu, K.

2013-12-01

366

Processing a glass fiber reinforced vinyl ester composite with nanotube enhancement of interlaminar shear strength  

Microsoft Academic Search

Carbon nanotubes have been considered as a promising means of enhancing the properties of advanced composites in a range of polymer systems. Expected property enhancements include high strength and stiffness, improved toughness, impact and through-thickness properties. Z-axis properties like shear strength are of special interest for laminated composite structures subjected to transverse loads. This paper reports the processing of a

Jiang Zhu; Ashraf Imam; Roger Crane; Karen Lozano; Valery N. Khabashesku; Enrique V. Barrera

2007-01-01

367

New Model for Estimation of Shear Strength of Reinforced Concrete Interior Beam-Column Joints  

Microsoft Academic Search

A new model is developed for estimating the shear strength of RC interior beam-column connections. The new model is based on the methods used in current ACI and AIJ design codes with modifications for effective area of joint panel and effective concrete strength. A database of interior beam-column connections is constructed from previous experimental studies and the influence of transverse

BASHIR AHMAD Muhsen; HISASHI Umemura

2011-01-01

368

Contained Left Ventricular Free Wall Rupture following Myocardial Infarction  

PubMed Central

Rupture of the free wall of the left ventricle occurs in approximately 4% of patients with infarcts and accounts for approximately 20% of the total mortality of patients with myocardial infractions. Relatively few cases are diagnosed before death. Several distinct clinical forms of ventricular free wall rupture have been identified. Sudden rupture with massive hemorrhage into the pericardium is the most common form; in a third of the cases, the course is subacute with slow and sometimes repetitive hemorrhage into the pericardial cavity. Left ventricular pseudoaneurysms generally occur as a consequence of left ventricular free wall rupture covered by a portion of pericardium, in contrast to a true aneurysm, which is formed of myocardial tissue. Here, we report a case of contained left ventricular free wall rupture following myocardial infarction.

Shiyovich, Arthur; Nesher, Lior

2012-01-01

369

Delayed hepatothorax due to right-sided traumatic diaphragmatic rupture.  

PubMed

We present a 48-year-old man with delayed hepatothorax due to right-sided traumatic diaphragmatic rupture. An initial chest radiograph showed no specific signs except elevation of the right diaphragmatic border. The diagnosis was confirmed by coronal reformatted helical computed tomography (CT) imaging, which revealed intrathoracic displacement of the liver. A follow-up chest radiograph revealed gradual elevation of the right diaphragmatic border, suggesting worsening of the diaphragmatic rupture and progression of hepatothorax, resulting in severe atelectasis of the right lung. Therefore, surgical repair of the diaphragmatic rupture was performed. Impaction of the liver through the diaphragmatic ruptured region was observed. Chest radiographic examination after the operation revealed a more normal position of the right diaphragmatic border and resolution of the right lung atelectasis. The problems associated with the diagnosis and operative treatment of hepatothorax with right-sided traumatic diaphragmatic ruptures are discussed in the light of this case report. PMID:18018610

Igai, Hitoshi; Yokomise, Hiroyasu; Kumagai, Kazumi; Yamashita, Susumu; Kawakita, Kenya; Kuroda, Yasuhiro

2007-10-01

370

An investigation of transverse localization in a disordered waveguide array containing plasma materials  

NASA Astrophysics Data System (ADS)

We investigate wave propagation through a disordered waveguide array composed of plasma materials. We first consider a system in which both the low and high index regions are plasma materials. To introduce disorder through the system, the electron plasma densities of the high index regions are selected to be random numbers. We study the effect of disorder strength on transverse localization. Our numerical results reveal that increasing the disorder level improves the quality of the transverse localization. The dependence of the localization features on the plasma density of the low index media and average of the plasma density of the high-index regions is also studied. Localization degrades with increasing plasma density of the low index media. However, transverse localization improves with increasing average plasma density of the high-index regions. Thus, using plasma materials in the disordered photonic lattices makes it possible to control transverse localization characteristics with plasma parameters, as well as applying an external magnetic field. Second, we consider a disordered waveguide array composed alternately of normal and plasma materials. The influence of the operating wavelength variation on the transverse localization is also discussed in this disordered system. It is demonstrated that the effective width of the injected wave at the output end increases with increasing wavelength. In this case, the increase of the average refractive index of normal materials leads to the improvement of transverse localization.

Ghasempour Ardakani, Abbas

2014-07-01

371

Rupture of De Novo Anterior Communicating Artery Aneurysm 8 Days after the Clipping of Ruptured Middle Cerebral Artery Aneurysm  

PubMed Central

Rapidly developed de novo aneurysm is very rare. We present a rapidly developed and ruptured de novo anterior communicating aneurysm 8 days after the rupture of another aneurysm. This de novo aneurysm was not apparent in the initial 3-dimensional computed tomography and digital subtraction angiography. We reviewed the literature and discussed possible mechanisms for the development of this de novo aneurysm.

Ha, Sung-Kon; Kim, Sang-Dae; Kim, Se-Hoon

2013-01-01

372

Poroelastic Bimaterial Effects in Rupture Dynamics  

NASA Astrophysics Data System (ADS)

A mismatch of elastic properties across a fault induces normal stress changes during spatially nonuniform slip. Recently, Rudnicki and Rice (2006) showed that similar effects follow from a mismatch of poroelastic properties (e.g., permeability) within fluid-saturated damage fringes along the fault walls; those induce changes in pore pressure on the slip plane and hence changes in effective normal stress during slip. The sign of both changes can be either positive or negative, and they need not agree. Both signs reverse when the rupture propagates in the opposite direction, introducing asymmetry into the rupture process. We model a poroelastic fault zone cut by a planar fault separating regions of potentially different poroelastic properties. Slip compresses one side of the fault while dilating the opposite side. The resulting undrained pore pressure change is of opposite sign across the fault, and pore fluid diffuses to ensure continuity of pore pressure and fluid flux across the fault. Pore pressure on the fault decreases if the compressive side is less permeable (all other quantities being equal) and vice-versa. The poroelastic properties are measured over the hydraulic diffusion length, generally of order a few millimeters in well-sheared fault core cataclasite for a slip duration of a few seconds. (Poroelastic effects are essentially negligible on that time scale at greater distances from the fault because of vastly smaller pore pressure gradients; the material responds there like a classical elastic solid with moduli based on undrained poroelastic response.) Steady sliding of two half-spaces (neglecting shear heating) with identical elastic properties but a mismatch in poroelastic properties is unstable to perturbations for all non-zero values of the friction coefficient and Skempton's coefficient. The growth rate is proportional to the wavenumber of the perturbation, rendering this problem ill-posed in a manner similar to that for elastic mismatch. When both elastic and poroelastic properties are discontinuous across the fault, sliding is unstable for arbitrarily small friction coefficients if the elastic mismatch permits the existence of a generalized Rayleigh wave. When the poroelastic effect opposes the elastic bimaterial effect, there exists a critical parameter set at which the effects precisely balance and sliding is neutrally stable. The propagation direction of the unstable mode reverses across this critical state. For a large elastic mismatch, the generalized Rayleigh wave goes out of existence and sliding is stabilized for friction coefficients less than some critical value; this value is altered by the poroelastic response. This stability analysis is augmented by calculations of spontaneous ruptures on slip-weakening faults across which elastic and poroelastic properties may be discontinuous. Prakash-Clifton regularization permits convergent solutions in the otherwise ill-posed regime. The numerical method is validated by comparison to analytical solutions for the rupture of a line asperity between dissimilar elastic solids in frictionless contact (Harris and Day, 1997) and for a self-similar crack between identical elastic solids but with a mismatch in poroelastic properties.

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

2006-12-01

373

Ruptured Rathke cleft cyst mimicking pituitary apoplexy.  

PubMed

Rathke cleft cysts (RCCs) are benign cystic lesions of the sellar and suprasellar region that are asymptomatic in most cases. Occasionally, compression of the optic pathway and hypothalamo-pituitary structures may cause clinical symptoms, such as headaches, visual deficits and endocrinopathies. Acute presentation caused by hemorrhage into an RCC have been described in the literature, and the term "Rathke cleft cyst apoplexy" has been coined. We present the case of a 32-year-old man with acute onset of meningitis-type symptoms and imaging findings resembling hemorrhagic pituitary tumor apoplexy. In retrospect, clinical symptoms, intraoperative appearance, and histologic examination were compatible with the diagnosis of nonhemorrhagic rupture of an RCC. Thus, the clinical presentation of "Rathke cleft cyst apoplexy" is not necessarily caused by hemorrhage. PMID:23696292

Neidert, Marian Christoph; Woernle, Christoph Michael; Leske, Henning; Möller-Goede, Diane; Pangalu, Athina; Schmid, Christoph; Bernays, René-Ludwig

2013-12-01

374

Disorganisation: a model for 'early amnion rupture'?  

PubMed

The hypothesis of an intrinsic defect of germ plasma put forward by Streeter to explain the abnormalities observed in 'amniotic bands sequence' (ABS) was not supported by Torpin, who suggested that the bands derived from early amnion rupture, with formation of mesodermal strings and naked chorion, which then constricted or adhered to fetal parts. Recently, several authors have recorded and discussed possible mechanisms for 'non-band related' malformations in patients with otherwise typical limb constrictions and amputations. The mouse mutant disorganisation (Ds) is a semidominant with 72% of heterozygotes manifesting abnormalities, which include cranioschisis, limb duplications and deficiencies, gastro/thoracoschisis, and papillae protruding from other parts of the body. We report similar abnormalities including papillae in five fetuses and one newborn with ABS and, based on these observations and published reports, we suggest that a human homologue for Ds may be the cause of at least some examples of ABS. PMID:2746613

Donnai, D; Winter, R M

1989-07-01

375

The untreated anterior cruciate ligament rupture.  

PubMed

Forty-nine patients (52 knees) with untreated anterior cruciate ligament (ACL) ruptures were evaluated an average of 14 years after injury. The results were compared with those of a ten-year follow-up study on the same patients. Eighty-six percent of the knees had one or both menisci removed. There had been little change in symptoms, except that the incidence of giving way had decreased. The incidence of anterior laxity and rotary instability continued to be high. Seventy-five percent of the patients continued to participate in strenuous sports. The incidence of degenerative changes on roentgenograms had increased, with one-third of the knees demonstrating joint space narrowing or unequivocal evidence of osteoarthritis. Development of degenerative changes was associated with varus deformity, meniscectomy, and relatively heavy body weight. PMID:6821986

McDaniel, W J; Dameron, T B

1983-01-01

376

TRANSVERSE SPIN AT PHENIX AND FUTURE PLANS.  

SciTech Connect

The PHENIX experiment took data with transversely polarized proton beams in 2001-2002 and measured the transverse single spin asymmetries in inclusive neutral pion and non-identified charge hadrons at midrapidity and {radical} s = 200 GeV. The data near X{sub F} {approx} 0 cover a transverse momentum range from 0.5 to 5.0 GeV/c. The observed asymmetries are consistent with zero with good statistical accuracy. This paper presents the current work in light of earlier measurements at lower energies in this kinematic region and the future plans of the PHENIX detector.

MAKDISI,Y. (FOR THE PHENIX COLLABORATION)

2005-01-28

377

Congenital Osseus Bridging of Lumbar Transverse Processes  

PubMed Central

Osseous bridging between lumbar transverse processes is an uncommon condition that may cause low back pain. In most cases, its etiology is alleged to be trauma to the back and only rarely has a congenital origin been indicated. Furthermore, most reported cases involved adults, the majority of whom were middle-aged. Here, the authors describe the case of the youngest girl reported to date with congenital transverse process bridging. As far as the authors' knowledge, there has been no report of congenital bridging of transverse processes in children or adolescents in Korea.

Kim, Jae Ho; Kim, Hyeun Sung

2012-01-01

378

Transverse Emittance Reduction with Tapered Foil  

SciTech Connect

The idea of reducing transverse emittance with tapered energy-loss foil is proposed by J.M. Peterson in 1980s and recently by B. Carlsten. In this paper, we present the physical model of tapered energy-loss foil and analyze the emittance reduction using the concept of eigen emittance. The study shows that, to reduce transverse emittance, one should collimate at least 4% of particles which has either much low energy or large transverse divergence. The multiple coulomb scattering is not trivial, leading to a limited emittance reduction ratio. Small transverse emittances are of essential importance for the accelerator facilities generating free electron lasers, especially in hard X-ray region. The idea of reducing transverse emittance with tapered energy-loss foil is recently proposed by B. Carlsten [1], and can be traced back to J.M. Peterson's work in 1980s [2]. Peterson illustrated that a transverse energy gradient can be produced with a tapered energy-loss foil which in turn leads to transverse emittance reduction, and also analyzed the emittance growth from the associated multiple coulomb scattering. However, what Peterson proposed was rather a conceptual than a practical design. In this paper, we build a more complete physical model of the tapered foil based on Ref. [2], including the analysis of the transverse emittance reduction using the concept of eigen emittance and confirming the results by various numerical simulations. The eigen emittance equals to the projected emittance when there is no cross correlation in beam's second order moments matrix [3]. To calculate the eigen emittances, it requires only to know the beam distribution at the foil exit. Thus, the analysis of emittance reduction and the optics design of the subsequent beam line section can be separated. In addition, we can combine the effects of multiple coulomb scattering and transverse energy gradient together in the beam matrix and analyze their net effect. We find that,when applied to an electron linac or electron beam line, the energy spread increase and angular growth due to multiple scattering are not trivial; as a result, the transverse emittance can only be reduced with a limited ratio, e.g. down to about 65% the original value. The contents of this paper are arranged as follows. In Sec. II, we build the physical model of the tapered foil, derive the transverse eigen emittance and discuss the emittance reduction criteria. In Sec. III, we implement numerical simulations to verify the physical model; and in Sec. IV, we present numerical experiments and subsequent beam line to remove the transverse energy gradient to demonstrate the applicability of such method. Conclusions are given in the last section.

Jiao, Yi; Chao, Alex; Cai, Yunhai; /SLAC

2011-12-09

379

Ferroelectric Cathodes in Transverse Magnetic Fields  

SciTech Connect

Experimental investigations of a planar ferroelectric cathode in a transverse magnetic field up to 3 kGs are presented. It is shown that the transverse magnetic field affects differently the operation of ferroelectric plasma cathodes in ''bright'' and ''dark'' modes in vacuum. In the ''bright'' mode, when the surface plasma is formed, the application of the transverse magnetic field leads to an increase of the surface plasma density. In the ''dark'' mode, the magnetic field inhibits the development of electron avalanches along the surface, as it does similarly in other kinds of surface discharges in the pre-breakdown mode.

Alexander Dunaevsky; Yevgeny Raitses; Nathaniel J. Fisch

2002-07-29

380

Marked pathological changes proximal and distal to the site of rupture in acute Achilles tendon ruptures  

Microsoft Academic Search

A laboratory study was performed to evaluate the histopathological features of the macroscopically intact portion of the Achilles\\u000a tendon in patients undergoing surgery for an acute rupture of the Achilles tendon. Tendon samples were harvested from 29 individuals\\u000a (21 men, 8 women; mean age: 46 ± 12) who underwent repair of an Achilles tendon tear tear, and from 11 male patients who

Nicola MaffulliUmile; Umile Giuseppe Longo; Gayle D. Maffulli; Carla Rabitti; Anil Khanna; Vincenzo Denaro

2011-01-01

381

Traumatic diaphragmatic rupture: associated injuries and outcome.  

PubMed Central

A retrospective case note analysis was performed on all patients treated for traumatic diaphragmatic rupture (TDR) at a major teaching hospital between January 1990 and August 1998. Patients were identified from the prospectively maintained UK Trauma and Research Network Database. Of the 480 cases of torso trauma admitted during the study period, 16 (3.3%) had TDR. Blunt trauma accounted for 13 (81%) of the injuries. A radiological pre-operative diagnosis was made in 10 (62.5%) patients. Seven of these were made on initial chest radiography, two on ultrasound scan and one on computed tomography. All patients underwent a midline laparotomy and TDR was subsequently diagnosed at operation in 6 patients. The left hemidiaphragm was ruptured in 14 (87.5%) patients and there was visceral herniation in 8 (50%). Twelve patients with blunt trauma had associated abdominal and extra-abdominal injuries, but only one of the three patients with penetrating trauma had other injuries. The median Injury Severity Score (range) was 21 (9-50). The median time (range) spent on the intensive care unit was 2 days (0-35 days). Pulmonary complications occurred in 7 (44%) patients. Two (12.5%) patients died from associated head injuries. TDR results from blunt and penetrating torso trauma, is uncommon, rarely occurs in isolation and is associated with a high morbidity and mortality. A high index of suspicion makes early diagnosis more likely as initial physical and radiological signs may be lacking. Images Figure 1 Figure 2 Figure 3 (A) Figure 3 (B)

Simpson, J.; Lobo, D. N.; Shah, A. B.; Rowlands, B. J.

2000-01-01

382

Mechanical strength of microcapsules made of different wall materials.  

PubMed

The mechanical strength of microcapsules made of three different wall materials, including melamine-formaldehyde resin, urea-formaldehyde resin and gelatin-gum arabic coacervate, were measured by a micromanipulation technique. Single microcapsules were compressed to large deformations or rupture and the force being imposed on them were measured simultaneously. Melamine-formaldehyde and urea-formaldehyde microcapsules showed clear bursting under compression, and their bursting force, deformation at bursting and deformation at a pesudo yield point were determined. Gelatin microcapsules did not show clear bursting under compression, and their mechanical strength was characterized by the force required to cause their deformation to 50%. The mechanical strengths of these three types of microcapsules are compared in this paper. PMID:12176269

Sun, G; Zhang, Z

2002-08-21

383

Transverse mode coupling instability in the VLHC.  

National Technical Information Service (NTIS)

We present the results of calculation of transverse mode coupling instability (TMCI) thresholds for Very Large Hadron Collider (VLHC). The estimates are done with use of conventional approach and more sophisticated mode dynamics analysis. We found the RF ...

V. V. Danilov V. D. Shiltsev

1998-01-01

384

Transverse sound in differentially moving superfluid helium  

NASA Astrophysics Data System (ADS)

There exists a transverse sound mode in superfluid helium, in addition to the first and second sound modes. In this mode, the velocity of the normal component oscillates in the direction perpendicular to the wave vector; hence, it is named the transverse mode. We analyze this mode at arbitrary values of the relative velocity of the normal and superfluid components. In general, temperature, pressure, and superfluid velocity also oscillate. The general relations between the amplitudes of the oscillating variables in the transverse mode are found in a general direction of the wave vector with respect to the relative velocity of the normal fluid and superfluid. We estimate the attenuation of the transverse mode in phonon pulses and discuss the possibility of detecting it experimentally.

Adamenko, I. N.; Nemchenko, K. E.; Slipko, V. A.; Wyatt, A. F. G.

2008-04-01

385

Transverse sacral fractures with anterior displacement  

PubMed Central

Transverse fractures of the sacrum with anterior displacement are the rarest type of transverse sacral fractures. They usually occur at the S1–S2 region in suicide jumpers. A clinical study was performed to evaluate the diagnosis, treatment and outcome of transverse sacral fractures with anterior displacement. We present six patients with a transverse fracture of the sacrum with anterior displacement. All patients presented with bowel and bladder dysfunction, perineal anesthesia, sensory and motor deficits at the lower extremities. Prompt diagnosis of the sacral fracture was obtained in five of the six patients. Operative treatment including lumbosacral laminectomies, spine instrumentation and fusion was done in all patients. Neurological recovery was almost complete in one patient, incomplete in four patients, and none in one patient. Although reduction of the fracture was not ideal in many of these patients, long-term clinical and radiographic follow-up, and neurological improvement were rewarding.

Sapkas, George S.; Mavrogenis, Andreas F.

2007-01-01

386

Transverse-Wave High-Power Tube.  

National Technical Information Service (NTIS)

Research and development work is described on a traveling-wave power amplifier tube employing transverse-wave interaction between the negative synchronous wave and a circuit wave on a balanced structure. The theoretical advantage in this arrangement is th...

C. B. Crumly R. A. Larsen

1968-01-01

387

Transversity from First Principles in QCD.  

National Technical Information Service (NTIS)

Transversity observables, such as the T-odd Sivers single-spin asymmetry measured in deep inelastic lepton scattering on polarized protons and the distributions which are measured in deeply virtual Compton scattering, provide important constraints on the ...

S. J. Brodsky

2011-01-01

388

Elevated temperature strength of fine-grained INCONEL alloy MA754  

Microsoft Academic Search

Elevated temperature tensile and creep-rupture tests were performed on INCONEL alloy MA754 in an as-rolled, fine-grained condition.\\u000a Tensile tests were performed at 25 C, 800 C, 900 C, and 1000 C; creep-rupture tests were performed at 800 C, 900 C,\\u000a and 1000 C. the elevated temperature strength in the fine-grained condition was approximately 25 pct of that the coarse-grained,\\u000a annealed

T. C. Totemeier; T. M. Lillo; J. A. Simpson

2005-01-01

389

Chiral dynamics and peripheral transverse densities  

SciTech Connect

In the partonic (or light-front) description of relativistic systems the electromagnetic form factors are expressed in terms of frame-independent charge and magnetization densities in transverse space. This formulation allows one to identify the chiral components of nucleon structure as the peripheral densities at transverse distances b = O(M{sub {pi}}{sup -1}) and compute them in a parametrically controlled manner. A dispersion relation connects the large-distance behavior of the transverse charge and magnetization densities to the spectral functions of the Dirac and Pauli form factors near the two--pion threshold at timelike t = 4 M{ sub {pi}}{sup 2}, which can be computed in relativistic chiral effective field theory. Using the leading-order approximation we (a) derive the asymptotic behavior (Yukawa tail) of the isovector transverse densities in the "chiral" region b = O(M{sub {pi}}{sup -1}) and the "molecular" region b = O(M{sub N}{sup 2}/M{sub {pi}}{sup 3}); (b) perform the heavy-baryon expansion of the transverse densities; (c) explain the relative magnitude of the peripheral charge and magnetization densities in a simple mechanical picture; (d) include Delta isobar intermediate states and study the peripheral transverse densities in the large-N{ sub c} limit of QCD; (e) quantify the region of transverse distances where the chiral components of the densities are numerically dominant; (f) calculate the chiral divergences of the b{sup 2}-weighted moments of the isovector transverse densities (charge and anomalous magnetic radii) in the limit M{sub {pi}} -> 0 and determine their spatial support. Our approach provides a concise formulation of the spatial structure of the nucleon's chiral component and offers new insights into basic properties of the chiral expansion. It relates the information extracted from low-t elastic form factors to the generalized parton distributions probed in peripheral high-energy scattering processes.

Granados, Carlos G. [Uppsala University (Sweden); Weiss, Christian [JLAB, Newport News, VA (United States)

2014-01-01

390

Inclusive eta Production at Large Transverse Momenta  

Microsoft Academic Search

We have measured the ratio of inclusive production of eta to pi0 at transverse momenta above 1.5 GeV\\/c. Results are presented for various meson and proton beams with momenta of 100, 200, and 300 GeV\\/c incident upon a hydrogen target. The etapi0 production ratio is found to be independent of incident beam momentum and of the transverse and longitudinal momenta

G. J. Donaldson; H. A. Gordon; K.-W. Lai; I. Stumer; A. V. Barnes; D. J. Mellema; A. V. Tollestrup; R. L. Walker; O. I. Dahl; R. A. Johnson; A. Ogawa; M. Pripstein; S. R. Shannon

1978-01-01

391

Dispersion and the transverse aether drag  

Microsoft Academic Search

THERE has been controversy about the correct expression of the displacement, d, introduced by the transverse motion of a dispersive dielectric slab on a light beam. Player1 proposed the formula d=nut(ng - n-1)\\/c, where nu is the slab transverse velocity, t the slab thickness, ng and n the group and wave refractive indices of the medium, respectively, and c the

J. A. Arnaud

1976-01-01

392

Beam dynamics in transverse deflecting rf structures  

NASA Astrophysics Data System (ADS)

The beam dynamics in transverse deflecting structures, operating in streaking mode, is discussed concentrating on slightly nonrelativistic particle energies. Transverse offsets of the average trajectory, bunch lengthening, and defocusing as well as emittance growth due to nonlinearities of the cavity field are considered. The analysis of the deflecting field reveals the origin of nonlinearities and leads to proposals for their suppression. An optimized cavity design which combines minimal aberrations with a high rf efficiency is proposed.

Floettmann, Klaus; Paramonov, Valentin V.

2014-02-01

393

Effect of Time-dependent Rupture on Tsunami Generation  

NASA Astrophysics Data System (ADS)

Differential GPS data from the recent Chile 2009 and Japan 2011 seismic events have unveiled complex time-dependent ground motion dynamics during seismic rupture. Current tsunami modeling techniques usually ignore this time-dependent behavior in tsunami sources by assuming an instantaneous initial deformation field. Initial attempts to include time-dependent rupture behavior have motivated scientists to simulate this phenomenon as a series of instantaneous changes in the sea-floor. The present study investigates the effect of dynamic ground motion rupture on tsunami generation by including the time-dependent initial conditions in the derivation of the linear shallow-water wave equations. We then study the sensitivity of initial water surface deformation to time-dependent seafloor rupture by performing a parametric study of varying speed and rupture direction, while assuming a monotonic deformation from an initial pre-rupture state to a post-rupture final state. Numerical results for some selected scenarios are validated by comparing with analytical solutions of the non-homogeneous linear shallow-water equations.

Arcas, D.; Kanoglu, U.; Moore, C. W.; Aydin, B.

2013-12-01

394

Solving for Earthquake Rupture Rates on a Complex Fault Network  

NASA Astrophysics Data System (ADS)

We present preliminary results from an inverse method that solves for the long-term rate of all ruptures on the major mapped faults in California. This method is being developed for the 3rd Uniform California Earthquake Rupture Forecast (UCERF3). Building on the work of Andrews and Schwerer (2000), we solve for the rates of ruptures that are consistent with a) slip-rate constraints, b) paleoseismic event rates, and optional constraints such as c) a-priori rupture rate estimates, d) smoothness constraints, and e) constraints on the magnitude distribution. These constraints are linear, and allow us to formulate the system of equations as a matrix equation. Multiple solutions to the inverse problem are then sampled via a simulated annealing algorithm, which is important in terms of characterizing epistemic uncertainties. Using this inversion methodology, the ruptures themselves (or more specifically, the portions of the faults involved in each rupture) must be specified a priori. This requires generating simple rules to describe which faults or fault segments can rupture together in a single earthquake. We discuss possible criteria and their effect on the size of the solution space and the characteristics of the solution.

Page, M. T.; Field, E. H.

2010-12-01

395

Gastric rupture in horses: 50 cases (1979-1987).  

PubMed

A computer-based search was conducted of medical and necropsy records of horses admitted to the teaching hospital from Jan 1, 1979, to Dec 31, 1987, to obtain the records of all horses admitted to the hospital for colic and subsequently found to have gastric rupture. Fifty cases of gastric rupture were found. The records were reviewed to obtain data regarding peritoneal fluid analysis. Cell counts of these samples were often erroneous because debris and clumps of bacteria were counted when most WBC were lysed. A cross-sectional study of gastric rupture cases versus all other colic cases regarding season of admission revealed that there was no association between season and the occurrence of gastric rupture. There was also no increased risk associated with age, gender, breed, and the occurrence of gastric rupture. One hundred colic cases, matched with the gastric rupture cases by year of admission, were randomly selected via a table of random numbers. A questionnaire regarding age, breed, gender, use of the horse, housing, diet, water source, deworming schedule, and medical history was completed from the medical records and phone conversations with the horse owners. The results indicated that horses on a diet of grass hay or grass/alfalfa hay only or those that drank water from a bucket, stream, or pond were at increased risk for having gastric rupture. In contrast, horses fed grain had a reduced risk. PMID:2298661

Kiper, M L; Traub-Dargatz, J; Curtis, C R

1990-01-15

396

Daughter bubble cascades produced by folding of ruptured thin films.  

PubMed

Thin liquid films, such as soap bubbles, have been studied extensively for over a century because they are easily formed and mediate a wide range of transport processes in physics, chemistry and engineering. When a bubble on a liquid-gas or solid-gas interface (referred to herein as an interfacial bubble) ruptures, the general expectation is that the bubble vanishes. More precisely, the ruptured thin film is expected to retract rapidly until it becomes part of the interface, an event that typically occurs within milliseconds. The assumption that ruptured bubbles vanish is central to theories on foam evolution and relevant to health and climate because bubble rupture is a source for aerosol droplets. Here we show that for a large range of fluid parameters, interfacial bubbles can create numerous small bubbles when they rupture, rather than vanishing. We demonstrate, both experimentally and numerically, that the curved film of the ruptured bubble can fold and entrap air as it retracts. The resulting toroidal geometry of the trapped air is unstable, leading to the creation of a ring of smaller bubbles. The higher pressure associated with the higher curvature of the smaller bubbles increases the absorption of gas into the liquid, and increases the efficiency of rupture-induced aerosol dispersal. PMID:20535206

Bird, James C; de Ruiter, Riëlle; Courbin, Laurent; Stone, Howard A

2010-06-10

397

Transverse structure of the QCD string  

SciTech Connect

The characterization of the transverse structure of the QCD string is discussed. We formulate a conjecture as to how the stress-energy tensor of the underlying gauge theory couples to the string degrees of freedom. A consequence of the conjecture is that the energy density and the longitudinal-stress operators measure the distribution of the transverse position of the string, to leading order in the string fluctuations, whereas the transverse-stress operator does not. We interpret recent numerical measurements of the transverse size of the confining string and show that the difference of the energy and longitudinal-stress operators is a particularly natural probe at next-to-leading order. Second, we derive the constraints imposed by open-closed string duality on the transverse structure of the string. We show that a total of three independent ''gravitational'' form factors characterize the transverse profile of the closed string, and obtain the interpretation of recent effective string theory calculations: the square radius of a closed string of length {beta} defined from the slope of its gravitational form factor, is given by (d-1/2{pi}{sigma})log({beta}/4r{sub 0}) in d space dimensions. This is to be compared with the well-known result that the width of the open string at midpoint grows as (d-1/2{pi}{sigma})log(r/r{sub 0}). We also obtain predictions for transition form factors among closed-string states.

Meyer, Harvey B. [Johannes Gutenberg Universitaet Mainz, Institut fuer Kernphysik, 55099 Mainz (Germany)

2010-11-15

398

Interaction of dynamic rupture with small-scale heterogeneities  

NASA Astrophysics Data System (ADS)

Broadband ground motion simulations, with frequencies up to 10Hz, are important for engineering purposes, in particular for seismic hazard assessment for critical facilities. One problem in such simulations is the generation of high frequency radiation emitted during the dynamic rupture process. Ad-hoc kinematic rupture characterizations can be tweaked through empirical models to radiate over the desired frequency range, but their physical consistency remains questionable. In contrast, for physically self-consistent dynamic rupture modeling, controlled by friction, material parameters and the adopted physical laws, the mechanism that may lead to appropriate high-frequency radiation require heterogeneity in friction, stress, or fault geometry (or even all three quantities) at unknown but small length scales. Dunham at al. (2011) studied dynamic rupture propagation on rough faults in 2D, and described how fault roughness excites high-frequency radiation. In our study, we focus on the interaction of the dynamic rupture with small-scale heterogeneities on planar faults in 3D. We study effects of the interaction of dynamic rupture with 1) small-scale heterogeneities in the medium (that is, randomized 3D wave speed and density variations), and 2) small-scale heterogeneities in the frictional parameters. Our numerical results show significant variations in rupture velocity or peak slip velocity if small-scale heterogeneities are present. This indicates that the dynamic rupture is sensitive to both types of spatial inhomogeneity. At the same time we observe that the resulting near-source seismic wave fields are not very sensitive to these rupture variations, indicating that wavefront healing effects may "simplify" the complex seismic radiation once the waves propagated several wave-lengths away from the fault.

Galis, Martin; Mai, P. Martin

2014-05-01

399

Exploring the transverse spin structure of the nucleon  

NASA Astrophysics Data System (ADS)

We discuss our present understanding of the transverse spin structure of the nucleon and of related properties originating from parton transverse motion. Starting from the transversity distribution and the ways to access it, we then address the role played by spin and transverse momentum dependent (TMD) distributions in azimuthal and transverse single spin asymmetries. The latest extractions of the Sivers, Collins and transversity functions are also presented.

D'Alesio, Umberto

2008-10-01

400

Exploring the transverse spin structure of the nucleon  

SciTech Connect

We discuss our present understanding of the transverse spin structure of the nucleon and of related properties originating from parton transverse motion. Starting from the transversity distribution and the ways to access it, we then address the role played by spin and transverse momentum dependent (TMD) distributions in azimuthal and transverse single spin asymmetries. The latest extractions of the Sivers, Collins and transversity functions are also presented.

D'Alesio, Umberto [Dipartimento di Fisica, Universita di Cagliari and INFN, Sezione di Cagliari, C.P. 170, I-09042, Monserrato, Cagliari (Italy)

2008-10-13

401

Character Strengths Among Youth  

Microsoft Academic Search

Four hundred and fiftynine students from 20 different high school classrooms in Michigan participated in focus group discussions about the character strengths included in the Values in Action Classifi- cation. Students were interested in the subject of good character and able to discuss with candor and sophistication instances of each strength. They were especially drawn to the positive traits of

Tracy A. Steen; Lauren V. Kachorek; Christopher Peterson

2003-01-01

402

Recognizing Neglected Strengths  

ERIC Educational Resources Information Center

To identify diverse student strengths and to learn how teachers can build instruction on those strengths, the author and his colleagues have conducted multiple studies among students in Alaska, the mainland United States, Kenya, and other countries. In a series of studies in Alaska and Kenya, the researchers measured the adaptive cultural…

Sternberg, Robert J.

2006-01-01

403

High strength, superplastic superalloy  

NASA Technical Reports Server (NTRS)

High strength superplastic superalloys are produced by extruding a pre-alloyed powder. The cast nickel base superalloy was remelted and converted to pre-alloyed powder by inert gas atomization. The superalloy shows high tensile strength and superplasticity and finds use in hot working and casting.

Ashbrook, R. L.; Freche, J. C.; Waters, W. J.

1969-01-01

404

Guide to transverse projections and mass-constraining variables  

SciTech Connect

This paper seeks to demonstrate that many of the existing mass-measurement variables proposed for hadron colliders (m{sub T}, m{sub eff}, m{sub T2}, missing p-vector{sub T}, h{sub T}, {radical}(s-circumflex){sub min}, etc.) are far more closely related to each other than is widely appreciated, and indeed can all be viewed as a common mass-bound specialized for a variety of purposes. A consequence of this is that one may understand better the strengths and weaknesses of each variable, and the circumstances in which each can be used to best effect. In order to achieve this, we find it necessary first to revisit the seemingly empty and infertile wilderness populated by the subscript 'T' (as in 'pe{sub T}') in order to remind ourselves what this process of transversification actually means. We note that, far from being simple, transversification can mean quite different things to different people. Those readers who manage to battle through the barrage of transverse notation distinguishing 'T' from 'v' or or from 'o', and 'early projection' from 'late projection', will find their efforts rewarded towards the end of the paper with (i) a better understanding of how collider mass variables fit together, (ii) an appreciation of how these variables could be generalized to search for things more complicated than supersymmetry, (iii) will depart with an aversion to thoughtless or naieve use of the so-called 'transverse methods' of any of the popular computer Lorentz-vector libraries, and (iv) will take care in their subsequent papers to be explicit about which of the 61 identified variants of the 'transverse mass' they are employing.

Barr, A. J. [Department of Physics, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); Khoo, T. J.; Lester, C. G. [Department of Physics, Cavendish Laboratory, JJ Thomson Avenue, Cambridge, CB3 0HE (United Kingdom); Konar, P. [Theoretical Physics Group, Physical Research Laboratory, Ahmedabad, Gujarat - 380 009 (India); Kong, K. [Department of Physics and Astronomy, University of Kansas, Lawrence, KA 66045 (United States); Matchev, K. T.; Park, M. [Department of Physics, University of Florida, Gainesville, Florida 32611 (United States)

2011-11-01

405

Spontaneous Uterine Rupture in the First Trimester: A Case Report  

PubMed Central

Uterine rupture is one of the most feared obstetric complications affecting the pregnant woman and fetus. Most of the cases have various risk factors and mainly occur during the second or third trimester. However, spontaneous uterine rupture during the first trimester is extremely rare. We experienced a case of spontaneous uterine rupture in a 36-yr-old multiparous woman without definite risk factors. The initial impression was a hemoperitoneum of an unknown origin with normal early pregnancy. Intensive surgical method would be needed for accurate diagnosis and immediate management in bad situation by hemoperitoneum even though a patient was early pregnancy.

Ryu, Ki-Young; Lee, Jong-In; Park, Moon-Il

2005-01-01

406

Minimum Energy Path to Membrane Pore Formation and Rupture  

NASA Astrophysics Data System (ADS)

We combine dynamic self-consistent field theory with the string method to calculate the minimum energy path to membrane pore formation and rupture. In the regime where nucleation can occur on experimentally relevant time scales, the structure of the critical nucleus is between a solvophilic stalk and a locally thinned membrane. Classical nucleation theory fails to capture these molecular details and significantly overestimates the free energy barrier. Our results suggest that thermally nucleated rupture may be an important factor for the low rupture strains observed in lipid membranes.

Ting, Christina L.; Appelö, Daniel; Wang, Zhen-Gang

2011-04-01

407

Minimum energy path to membrane pore formation and rupture.  

PubMed

We combine dynamic self-consistent field theory with the string method to calculate the minimum energy path to membrane pore formation and rupture. In the regime where nucleation can occur on experimentally relevant time scales, the structure of the critical nucleus is between a solvophilic stalk and a locally thinned membrane. Classical nucleation theory fails to capture these molecular details and significantly overestimates the free energy barrier. Our results suggest that thermally nucleated rupture may be an important factor for the low rupture strains observed in lipid membranes. PMID:21599415

Ting, Christina L; Appelö, Daniel; Wang, Zhen-Gang

2011-04-22

408

Best approach for the repair of distal biceps tendon ruptures  

PubMed Central

The preferred treatment of distal biceps tendon ruptures is by operative repair. However, the best approach for repair (single vs double incision) is still subject of debate. Grewal and colleagues recently presented the results of a randomized clinical trial evaluating two different surgical approaches for the repair of distal biceps tendon ruptures. Despite the fact that this article currently presents the highest level of evidence for the surgical repair of distal biceps tendon ruptures, we have some comments on the study that might be interesting to discuss. We think that some of the results and conclusions presented in this study need to be interpreted in the light of these comments.

Kodde, Izaak F; van den Bekerom, Michel P J; Eygendaal, Denise

2013-01-01

409

Endovascular occlusion of a ruptured popliteal artery aneurysm.  

PubMed

Popliteal artery aneurysms are the most common of the peripheral aneurysms. Rupture is a rare complication of these aneurysms. Here we present a case of a ruptured popliteal aneurysm in a patient with severe joint disease and immobility due to rheumatoid arthritis. The condition was treated endovascularly with an Amplatzer arterial occlusion device. The aneurysm was successfully thrombosed without inducing critical limb ischemia, as the distal popliteal was chronically occluded. Ligation of peripheral aneurysms is an infrequent treatment without simultaneous bypass graft placement. Endovascular occlusion of ruptured popliteal aneurysms should be considered a valid therapeutic strategy where exclusion bypass is not required due to distal arterial occlusion. PMID:20356867

Smith, R J Paul; Gajendragadkar, Parag R; Winterbottom, Andrew P; Cooper, David G; Hayes, Paul D; Boyle, Jonathan R

2010-05-01

410

Splenic rupture associated with primary CMV infection, AMSAN, and IVIG.  

PubMed

Splenic rupture is a rare complication of primary cytomegalovirus infection, but has not been reported after administration of intravenous immunoglobulin or in the setting of the Guillain-Barré syndrome and its many variants, which often lead to treatment with intravenous immunoglobulin. There is strong evidence that intravenous immunoglobulin causes sequestration of erythrocytes in the spleen and extravascular hemolytic anemia. This may result in a two-hit scenario that clinicians should be aware of, where a patient who is at risk for splenic rupture due to primary cytomegalovirus infection receives intravenous immunoglobulin as treatment for the cytomegalovirus-associated Guillain-Barré syndrome, further increasing their risk of rupture. PMID:24856574

de Havenon, Adam; Davis, Gary; Hoesch, Robert

2014-07-15

411

Subretinal neovascularization following ruptured retinal arterial macroaneurysm: case report.  

PubMed

A 51-year-old black woman was referred to our Retina Clinic for evaluation of loss of vision in her left eye. She was previously diagnosed with a ruptured retinal arterial macroaneurism (RAM) in the same eye. The ophthalmoscopic examination of the affected eye disclosed a subretinal lesion with some hemorrhage and exudation in the same area previously diagnosed with ruptured RAM. Fluorescein angiography revealed a gradually hyperfluorescent net of vessels located in the subfoveal region, consistent with the diagnosis of subretinal neovascular membrane. In this paper we stress the possibility of subretinal neovascularization following a ruptured RAM, even as a rare event. PMID:17906769

Vianna, Raul N G; Kassuga, Augusto; Onofre, Gabriela; Ecard, Virginia; Burnier, Miguel N

2007-01-01

412

The rupture of a single liquid aluminium alloy film.  

PubMed

The present study is based on the idea of understanding the rupture of films in metal foams by studying free standing metallic films as a model system. Liquid dynamics, the velocity of the rupturing material as well as the behaviour of ceramic particles inside the melt were analysed optically ex situ and by synchrotron X-ray radiography in situ. It was found that the resistance of films to rupture is mainly based on the interaction between solid particles and an immobile oxide skin, the formation of which depends on the oxygen content of the surrounding atmosphere and the presence of magnesium. PMID:24854899

Heim, K; García-Moreno, F; Vinod Kumar, G S; Rack, A; Banhart, J

2014-07-14

413

A Controllable Earthquake Rupture Experiment on the Homestake Fault  

NASA Astrophysics Data System (ADS)

Fault-slip is typically simulated in the laboratory at the cm-to-dm scale. Laboratory results are then up-scaled by orders of magnitude to understand faulting and earthquakes processes. We suggest an experimental approach to reactivate faults in-situ at scales ~10-100 m using thermal techniques and fluid injection to modify in situ stresses and the fault strength to the point where the rock fails. Mines where the modified in-situ stresses are sufficient to drive faulting, present an opportunity to conduct such experiments. During our recent field work in the former Homestake gold mine in the northern Black Hills, South Dakota, we found a large fault present on multiple mine levels. The fault is subparallel to the local foliation in the Poorman formation, a Proterozoic metamorphic rock deformed into regional-scale folds with axes plunging ~40° to the SSE. The fault extends at least 1.5 km along strike and dip, with a center ~1.5 km deep. It strikes ~320-340° N, dips ~45-70° NE, and is recognized by a ~0.3-0.5 m thick distinct gouge that contains crushed host rock and black material that appears to be graphite. Although we could not find clear evidence for fault displacement, secondary features suggest that it is a normal fault. The size and distinct structure of this fault make it a promising target for in-situ experimentation of fault strength, hydrological properties, and slip nucleation processes. Most earthquakes are thought to be the result of unstable slip on existing faults, Activation of the Homestake fault in response to the controlled fluid injection and thermally changing background stresses is likely to be localized on a crack-like patch. Slow patch propagation, moderated by the injection rate and the rate of change of the background stresses, may become unstable, leading to the nucleation of a small earthquake (dynamic) rupture. This controlled instability is intimately related to the dependence of the fault strength on the slip process and has been analyzed for the Homestake fault conditions. Scale analyses indicate that this transition occurs for the nucleation patch size ~1 m. This represents a fundamental limitation for laboratory experiments, where the induced dynamic patch could be tractable, and necessitates larger scale field tests ~10-100 m. The ongoing dewatering is expected to affect displacements in the fault vicinity. This poroelastic effect can be used to better characterize the fault. Nucleation, propagation, and arrest of dynamic fault slip is governed by fluid overpressure source, diffusion, and the magnitude of the background loading in relation to the peak and residual strength in the fault zone at the ambient pore pressure level. More information on in-situ stresses than currently available is required to evaluate the fault state. Yet, initial modeling suggests that a suitable place for such an experiment is where the Homestake fault intersects the 4850-ft mine level or at greater depths.

Germanovich, L. N.; Murdoch, L. C.; Garagash, D.; Reches, Z.; Martel, S. J.; Gwaba, D.; Elsworth, D.; Lowell, R. P.; Onstott, T. C.

2010-12-01

414

Anisotropy of high temperature strength in precipitation-hardened nickel-base superalloy single crystals  

NASA Technical Reports Server (NTRS)

The anisotropy of high temperature strength of nickel-base superalloy, Alloy 454, in service for advanced jet engine turbine blades and vanes, was investigated. Crystallographic orientation dependence of tensile yield strength, creep and creep rupture strength was found to be marked at about 760C. In comparison with other single crystal data, a larger allowance in high strength off-axial orientation from the 001 axis, and relatively poor strength at near the -111 axis were noted. From transmission electron microscopy the anisotropic characteristics of this alloy were explained in terms of available slip systems and stacking geometries of gamma-prime precipitate cuboids which are well hardened by a large tantalum content. 100 cube slip was considered to be primarily responsible for the poor strength of the -111 axis orientation replacing the conventional 111 plane slip systems.

Nakagawa, Y. G.; Terashima, H.; Yoshizawa, H.; Ohta, Y.; Murakami, K.

1986-01-01

415

Transverse match of high peak-current beam into the LANSCE DTL using PARMILA  

SciTech Connect

A new algorithm that uses a multiparticle PARMILA-based code to match high peak current H{sup +} beam ({approx}21 mA) into the Los Alamos Neutron Science Center (LANSCE) drift tube linac (DTL) has been developed. Two single cell rf bunchers in the low energy beam transport (LEBT) prepare the initially unbunched beam for DTL capture. The transverse distribution at the entrance to the DTL is set with four quadrupoles in the 1.26 m between the last transverse emittance measuring station and the DTL entrance. Previous matching algorithms used TRACE and TRACE 3-D to determine these quadrupole strengths. PARMILA simulation show this procedure produces non-zero mismatch and additional emittance growth through the DTL for high current beams. Because of strong space-charge forces and a rapidly forming longitudinal bunch, simple envelope calculations do not model the beam evolution in the LEBT well. A PARMILA model of this region was combined with ant iterative search routine to set the LEBT quadrupole strengths to achieve a better transverse match into the DTL. Simulations predict a significant reduction in transverse emittance at the exit of the DTL over the typical TRACE 3-D result.

Merrill, F.E.; Rybarcyk, L.J.

1996-09-01

416

Smooth transverse and longitudinal focusing in high-intensity ion linacs  

Microsoft Academic Search

We examine ion linac designs that start with a high energy radio- frequency quadrupole (RFQ) followed by either a drift-tube linac (DTL) or a coupled-cavity drift-tube linac (CCDTL). For high energies a conventional CCL follows the CCDTL. High RFQ output energy allows tailoring the transverse and longitudinal focusing strengths to match into the following structure. When the RFQ beam enters

James H. Billen; Harunori Takeda; Lloyd M. Young

1996-01-01

417

Aperture fixation instead of transverse tunnels at the patella for medial patellofemoral ligament reconstruction  

Microsoft Academic Search

Purpose  Medial patellofemoral ligament (MPFL) reconstruction is an effective option for the treatment of recurrent patellar instability.\\u000a Most techniques utilize the passage of a tendon graft through tunnels at the patella with the risk of patellar fracture. The\\u000a purpose of this study was to investigate the strength of the recent MPFL reconstruction techniques (transverse tunnel, interference\\u000a screw, anchor, and docking technique).

Onur HapaErtug; Ertu?rul Ak?ahin; Raif Özden; Murad Pepe; Ahmet Nedim Yanat; Yunus Do?ramac?; Ergun Bozda?; Emin Sünbülo?lu

418

Spontaneous choledochal cyst rupture in pregnancy with concomitant chronic pancreatitis.  

PubMed

Choledochal cysts are rare cystic transformations of the biliary tree that are increasingly diagnosed in adult patients. We report here a case of spontaneous rupture of a choledochal cyst in a pregnant young lady with chronic pancreatitis. PMID:23238690

Pal, Sandip; Simon, Ebby George; Koshy, Anoop K; Ramakrishna, B S; Raju, Ravish S; Vyas, Fredrick L; Joseph, Philip; Sitaram, V; Eapen, Anu

2013-03-01

419

Some Observations Regarding the Statistical Determination of Stress Rupture Minimums.  

National Technical Information Service (NTIS)

Observations concerning the statistical evaluation of creep data are presented. Methods currently employed in the determination of stress rupture minimum values can result in conflicting and necessarily invalid results. Anomalous behavior is principally a...

P. P. Pizzo

1971-01-01

420

Spontaneous Rupture of the Spleen Masquerading as a Pulmonary Infection  

PubMed Central

Atraumatic rupture of a normal spleen represents a rare clinical phenomenon. We report on an atypical presentation of a spontaneous splenic rupture in a 44-year-old previously healthy Greek male admitted to the emergency department due to left-sided pleuritic thoracic pain in the course of a pneumonia diagnosed 2 days before. During his stay, pain extended to the epigastric region. Abdominal examination revealed generalized tenderness. We presume that coughing secondary to respiratory infection was the main factor that precipitated splenic rupture. Despite the rarity of the condition physicians have to consider the diagnosis of spontaneous nontraumatic splenic rupture when they encounter healthy patients with nonspecific lower thoracic or abdominal pain. Prompt diagnosis is essential for a better outcome.

Kastanakis, Miltiades; Karona, Paraskevi; Fragiadakis, Giorgios; Kokkinos, Ioannis; Bobolakis, Emmanouil

2014-01-01

421

Subacute cardiac rupture complicating myocardial infarction. A case report.  

PubMed

The authors have focused this study on the emergence of subacute ventricular free wall rupture in a seventy-six-year-old patient admitted to hospital for inferior acute myocardial infarction. After six days he showed clinical signs of bradycardia and hypotension evolving to electromechanical dissociation. Given an adequate pharmacologic therapy, the patient was submitted to echocardiography, which was believed to be consistent with myocardial rupture, showing a moderate to large pericardial effusion. Pericardiocentesis of 150 mL of bloody fluid resulted in a further improvement in his hemodynamics. The patient underwent cardiac surgery with repair of the myocardial rupture through a large diaphragmatic infarction by a Dacron polyester fiber graft and pacemaker placement. In conclusion the authors confirm the relevant role of clinical data such as persistent chest pain and hemodynamic instability and the value of echocardiography in identifying subacute myocardial free wall rupture after an episode of acute myocardial infarction. PMID:8595015

Rosato, G; Santomauro, M; Stanco, G; Petillo, F; Sauro, R; Chiariello, M; Spampinato, N; Rotiroti, D

1996-02-01

422

Rupture of the Distal Tendon of the Biceps Brachii  

Microsoft Academic Search

Rupture of the distal biceps tendon is a relatively un- common clinical entity. Typically, patients are middle-aged males who experience a sudden forced extension against an actively con- tracting biceps muscle. Patients usually describe a \\

WILLIAM HAMILTON; MATTHEW L. RAMSEY

423

An unusual presentation of ruptured abdominal aorta aneurysm  

PubMed Central

Patient: Female, 65 Final Diagnosis: Ruptured abdominal aorta aneursym Symptoms: — Medication: — Clinical Procedure: After surgery the patient was discharged without sequelae Specialty: Surgery Objective: Unusual clinical course Background: Rupture of an abdominal aortic aneurysm is the most frightening and potentially life threatening complication of an abdominal aorta aneurysm (AAA). Patients present with atypical symptoms such as abdominal or flank pain, gastrointestinal hemorrhage, or shock. Case Report: A 65-year-old woman presented to our emergency department with gradually increasing left flank pain for 4–5 days. Her laboratory, radiologic, and physical examination revealed no significant pathology, so she was discharged, but 3 days later she was readmitted because her symptoms returned. Further research revealed a ruptured AAA and the patient was hospitalized for surgical intervention. Conclusions: Emergency physicians should keep in mind that AAA and its rupture can present with a wide range of symptoms that appear to be simple.

Durdu, Tamer; Yilmaz, Fevzi; Sonmez, Bedriye Muge; Ulgen, Sultan; Demir, Ali; Y?lmaz, Muhittin Serkan; Arslan, Engin Deniz; Hakbilir, Oktay

2013-01-01

424

An unusual case of cardiac tamponade: ruptured subaortic diverticulum.  

PubMed

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. PMID:20345853

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

2010-05-01

425

Onyx Embolization of Ruptured Intracranial Aneurysm Associated with Behçet's Disease.  

PubMed

Introduction. Intracranial aneurysms associated with Behçet's disease (BD) are a rare occurrence. They are fragile, thin-walled pseudoaneurysms, which have high tendency to rupture and present a therapeutic challenge. Case Presentation. We report a 26-year-old male with BD presented with subarachnoid hemorrhage due to ruptured middle cerebral artery aneurysm. Additionally, two unruptured aneurysms were identified. He underwent endovascular embolization using Onyx with successful obliteration of the ruptured aneurysm. Medical therapy resulted in regression of one and resolution of the other aneurysms. Conclusion. We describe the first report of the application of Onyx for obliteration of ruptured cerebral aneurysm in BD as a feasible and safe therapeutic option for patients who are not candidates for other techniques. PMID:24224110

Kurdi, Maher; Baeesa, Saleh; Bin-Mahfoodh, Mohammed; Kurdi, Khalil

2013-01-01

426

Diaphragm Rupture Effects on an Expanding Flow in a Tube.  

National Technical Information Service (NTIS)

The fundamental problem of diaphragm rupture was studied experimentally to determine the effects on an expandi