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1

Frequency-dependent effects of rupture for the 2004 Parkfield main shock, results from UPSAR  

NASA Astrophysics Data System (ADS)

frequency-dependent effects of rupture propagation of the Parkfield, California, earthquake (28 September 2004, M6) to the northwest along the San Andreas Fault can be seen in acceleration records at UPSAR (USGS Parkfield Seismic Array) in at least two ways. First, we can see the effects of directivity in the acceleration traces at UPSAR, which is about 11.5 km from the epicenter. Directivity or the seismic equivalent of a Doppler shift has been documented in many cases by comparing short-duration, high-amplitude pulses (P or S) in the forward direction with longer-duration body waves in the backward direction. In this case we detect a change from a relatively large amplitude, coherent, high-frequency signal at the start of rupture to a low-amplitude, low-coherent, low-frequency signal at about the time the rupture front transfers from the forward azimuth to the back azimuth at about 34-36 s (time is UTC and is the seconds after day 272 and 17 h and 15 min. S arrival is just after 30 s) for rays leaving the fault and propagating to UPSAR. The frequency change is obvious in the band about 5 to 30 Hz, which is significantly above the corner frequency of the earthquake (about 0.11 Hz). From kinematic source models, the duration of faulting is about 9.2 s, and the change in frequency is during faulting as the rupture extends to the northwest. Understanding the systematic change in frequency and amplitude of seismic waves in relation to the propagation of the rupture front is important for predicting strong ground motion. Second, we can filter the acceleration records from the array to determine if the low-frequency energy emerges from the same part of the fault as the high-frequency signal (e.g., has the same back azimuth and apparent velocity at UPSAR), an important clue to the dynamics of rupture. Analysis of sources of strong motion (characterized by relatively high frequencies) compared to kinematic slip models (relatively low frequency) for the 11 March 2011 Tohoku earthquake as well as Maule (27 February 2010) and Chi-Chi (20 September 1999) earthquakes show that high- and low-frequency sources do not have the same locations on the fault. In this paper we filter the accelerograms from UPSAR for the 2004 main shock in various passbands and then recompute the cross correlations to determine the vector slowness of the incoming waves. At Parkfield, it appears that for seismic waves with frequencies above 1 Hz, there is no discernible frequency-dependent difference in source position (up to 8 Hz) based on estimates of back azimuth and apparent velocity. However, at lower frequencies, sources appear to be from shallower depths and trail the high frequencies as the rupture proceeds down the fault. This result is greater than one standard deviation of an estimate of error, based on a new method of estimating error that is a measure of how broad the peak in correlation is and an estimate of the variance of the correlation values. These observations can be understood in terms of a rupture front that is more energetic and coherent near the front of rupture (radiating higher frequencies) and less coherent and less energetic (radiating in a lower frequency band) behind the initial rupture front. This result is a qualitative assessment of changes in azimuth and apparent velocity with frequency and time and does not include corrections to find the source location on the fault.

Fletcher, Jon B.

2014-09-01

2

Rupture process of a multiple main shock sequence: analysis of teleseismic, local and field observations of the Tennant Creek, Australia, earthquakes of January 22, 1988  

USGS Publications Warehouse

On January 22, 1988, three large intraplate earthquakes (with MS 6.3, 6.4 and 6.7) occurred within a 12-hour period near Tennant Creek, Australia. Broadband displacement and velocity records of body waves from teleseismically recorded data are analyzed to determine source mechanisms, depths, and complexity of rupture of each of the three main shocks. Hypocenters of an additional 150 foreshocks and aftershocks constrained by local arrival time data and field observations of surface rupture are used to complement the source characteristics of the main shocks. The interpretation of the combined data sets suggests that the overall rupture process involved unusually complicated stress release. Rupture characteristics suggest that substantial slow slip occurred on each of the three fault interfaces that was not accompanied by major energy release. Variation of focal depth and the strong increase of moment and radiated energy with each main shock imply that lateral variations of strength were more important than vertical gradients of shear stress in controlling the progression of rupture. -from Authors

Choy, G.L.; Bowman, J.R.

1990-01-01

3

Aftershock patterns and main shock faulting  

USGS Publications Warehouse

We have compared aftershock patterns following several moderate to large earthquakes with the corresponding distributions of coseismic slip obtained from previous analyses of the recorded strong ground motion and teleseismic waveforms. Our results are consistent with a hypothesis of aftershock occurrence that requires a secondary redistribution of stress following primary failure on the earthquake fault. Aftershocks followng earthquakes examined in this study occur mostly outside of or near the edges of the source areas indicated by the patterns of main shock slip. The spatial distribution of aftershocks reflects either a continuation of slip in the outer regions of the areas of maximum coseismic displacement or the activation of subsidiary faults within the volume surrounding the boundaries of main shock rupture. -from Authors

Mendoza, C.; Hartzell, S. H.

1988-01-01

4

Forecasting large aftershocks within one day after the main shock  

PubMed Central

Forecasting the aftershock probability has been performed by the authorities to mitigate hazards in the disaster area after a main shock. However, despite the fact that most of large aftershocks occur within a day from the main shock, the operational forecasting has been very difficult during this time-period due to incomplete recording of early aftershocks. Here we propose a real-time method for efficiently forecasting the occurrence rates of potential aftershocks using systematically incomplete observations that are available in a few hours after the main shocks. We demonstrate the method's utility by retrospective early forecasting of the aftershock activity of the 2011 Tohoku-Oki Earthquake of M9.0 in Japan. Furthermore, we compare the results by the real-time data with the compiled preliminary data to examine robustness of the present method for the aftershocks of a recent inland earthquake in Japan. PMID:23860594

Omi, Takahiro; Ogata, Yosihiko; Hirata, Yoshito; Aihara, Kazuyuki

2013-01-01

5

A successful team treatment for left main shock syndrome  

PubMed Central

Acute myocardial infarction complicated by cardiogenic shock and left main coronary artery disease is called left main shock syndrome. It is reported that the morbility and mortality of the syndrome is approximately 0.46% and 55%–80%, respectively. However, the best treatment strategy in these cases is unknown. In this article, we present a patient with LMSS who successively underwent emergency percutaneous coronary intervention and coronary artery bypass grafting with hemodynamic support within 5 days. The patient is now on his three month uneventful out-patient follow-up. PMID:24133520

Que, Bin; Cheng, Yu-Tong; Gao, Hai; Hou, Xiao-Tong; Dong, Ran; Li, Nan; Nie, Shao-Ping

2013-01-01

6

Spontaneous adrenal pheochromocytoma rupture complicated by intraperitoneal hemorrhage and shock  

PubMed Central

MEN2A is a hereditary syndrome characterized by medullary thyroid carcinoma, hyperparathyroidism, and pheochromocytoma. Classically patients with a pheochromocytoma initially present with the triad of paroxysmal headaches, palpitations, and diaphoresis accompanied by marked hypertension. However, although reported as a rare presentation, spontaneous hemorrhage within a pheochromocytoma can present as an abdominal catastrophe. Unrecognized, this transformation can rapidly result in death. We report the only documented case of a thirty eight year old gentleman with MEN2A who presented to a community hospital with hemorrhagic shock and peritonitis secondary to an unrecognized hemorrhagic pheochromocytoma. The clinical course is notable for an inability to localize the source of hemorrhage during an initial damage control laparotomy that stabilized the patient sufficiently to allow emergent transfer to our facility, re-exploration for continued hemorrhage and abdominal compartment syndrome, and ultimately angiographic embolization of the left adrenal artery for control of the bleeding. Following recovery from his critical illness and appropriate medical management for pheochromocytoma, he returned for interval bilateral adrenal gland resection, from which his recovery was unremarkable. Our review of the literature highlights the high mortality associated with the undertaking of an operative intervention in the face of an unrecognized functional pheochromocytoma. This reinforces the need for maintaining a high index of suspicion for pheochromocytoma in similar cases. Our case also demonstrates the need for a mutimodal treatment approach that will often be required in these cases. PMID:21843357

2011-01-01

7

An unusual case of rupture of left sinus of valsalva aneurysm into main pulmonary artery  

PubMed Central

We report a case of left sinus of Valsalva aneurysm rupture into main pulmonary artery who underwent successful surgical correction. The preoperative diagnosis was facilitated by echocardiography, cardiac catheterization, and computed tomography. The benefits of surgery are sustained at 8 months on clinical and angiographic follow-up.

Munjewar, Chandrashekhar Bhimrao; Agrawal, Rahul D; Sharma, Satyavan

2014-01-01

8

Simulation of a main steam line break with steam generator tube rupture using trace  

SciTech Connect

A simulation of the OECD/NEA ROSA-2 Project Test 5 was made with the thermal-hydraulic code TRACE5. Test 5 performed in the Large Scale Test Facility (LSTF) reproduced a Main Steam Line Break (MSLB) with a Steam Generator Tube Rupture (SGTR) in a Pressurized Water Reactor (PWR). The result of these simultaneous breaks is a depressurization in the secondary and primary system in loop B because both systems are connected through the SGTR. Good approximation was obtained between TRACE5 results and experimental data. TRACE5 reproduces qualitatively the phenomena that occur in this transient: primary pressure falls after the break, stagnation of the pressure after the opening of the relief valve of the intact steam generator, the pressure falls after the two openings of the PORV and the recovery of the liquid level in the pressurizer after each closure of the PORV. Furthermore, a sensitivity analysis has been performed to know the effect of varying the High Pressure Injection (HPI) flow rate in both loops on the system pressures evolution. (authors)

Gallardo, S.; Querol, A.; Verdu, G. [Departamento de Ingenieria Quimica Y Nuclear, Universitat Politecnica de Valencia, Camino de Vera s/n, 46022, Valencia (Spain)

2012-07-01

9

Holocene slip rate and evidences of surface ruptures along the Main Frontal Thrust in Bhutan  

NASA Astrophysics Data System (ADS)

On the long term, the Himalayas absorb about 20 mm/yr of the convergence between the India and Eurasia plates. Morphotectonics studies East of Bhutan yielded an Holocene slip rate of 23 ± 6.2 mm/yr consistent with the 21 ± 1.5 mm/yr estimated in Nepal. In the past 1000 years, most of this crustal shortening is accommodated along the Main Frontal Thrust (MFT) by major M?8 earthquakes. Recent paleoseismic investigations between the meizoseismal areas of the 1934 Bihar-Nepal and 1950 Assam earthquakes west and east of the Bhutan suggest that a great earthquake may have ruptured a 700 to 800 km long section of the MFT during a single event around AD 1100. However, between 89°E and 92°E where the MFT runs along the southern border of the Kingdom of Bhutan, no major earthquakes has been recorded so far. In December 2012, we carried out a morphotectonic and paleosismologic study within two sites along the MFT in central Bhutan. We identified several sequences of abandoned fluvial terraces that have been uplifted along the fault. From a kinematic GPS survey, we estimated that the oldest terrace sequence (T2) displays a cumulative offset of ~60 m. A younger sequence (T1) showed an offset of ~4 m on the lower terrace (T1a) and ~9 m on the upper one (T1b). We interpret this 4 m uplift as the vertical component of the last seismic event while the 9 m may be the cumulative offset of the two last earthquakes. These preliminary observations may suggest that the latest seismic event as well as the penultimate event correspond to two major M>8 events. Samples for 14C, OSL and 10Be dating (charcoals, fine sands and quartz rich cobbles, respectively) have been collected in excavations within the different uplifted alluvial surfaces in order to determine the ages of these two last seismic events as well as the Holocene uplift and shortening rates. Compiled with the morphotectonic and paleoseismological data published in the literature, these new results will allow discussing the issue of seismic cycle along this portion of the Himalayan belt.

Ritz, Jean-François; Berthet, Théo; Pelgay, Phuntsho; Ferry, Mathieu; Drukpa, Dowchu; Cattin, Rodolphe; Chophel, Jamyang; Thinley, Kinzang

2013-04-01

10

Septic shock with tension fecothorax as a delayed presentation of a gunshot diaphragmatic rupture  

PubMed Central

Diaphragmatic rupture (DR) after thoracoabdominal trauma has a reported rate of 0.8% to 5% and up to 30% of diaphragmatic hernias are accompanied with delayed diagnosis. The DR occurs after high-energy blunt or penetrating (stab or gunshot wounds) trauma. The purpose of this article is to analyze the DR, its clinical presentation, complications and possible causes of the delay in diagnosis, whilst recording a rare interesting case. A 44-year old moribund male with a fifteen years history of paraplegia, came to the emergency department with a clinical presentation of extremely severe respiratory distress. Chest X-ray showed the colon present in the left hemithorax. The onset of symptoms was 48 hours before, resulting in hemodynamic instability and severe sepsis condition. Emergency left thoracotomy and laparotomy were carried out. A rupture of the left hemidiaphragm was found as well as intrathoracic presence of colon, incarcerated and perforated, feces and omentum, also incarcerated and necrotic. There were dense adhesions between the ectopic viscera and the thoracic structures. The necrotic parts of the colon and the omentum were mobilized, and then resected. The viable parts of the colon were laboriously reintroduced into the intraperitoneal cavity. We conclude that early diagnosis is crucial to the morbidity and mortality after DR. The course and the kinetic energy of bullets determine the extent of the wound and the size of the DR. The diagnosis of rupture of the diaphragm after penetrating trauma is sometimes difficult and delay can lead to life threatening complications. PMID:24255791

Papachristos, Ioannis C.; Daliakopoulos, Stavros I.; Chatzoulis, Kostas; Lampridis, Savvas; Svarnas, Grigorios; Katsiadramis, Ioannis

2013-01-01

11

Imaging the high-frequency energy radiation process of a main shock and its early aftershock sequence: The case of the 2008 Iwate-Miyagi Nairiku earthquake, Japan  

NASA Astrophysics Data System (ADS)

understand the energy release process that operates at the end of the main shock rupture and start of the aftershock activity, we propose an inversion method that uses continuous high-frequency seismogram envelopes of the main shock and early aftershocks (i.e., events that occur at short times after the main shock). In our approach, the aftershock sequence is regarded as a continuous energy release process, rather than a discrete time series of events. To correct for the contribution of coda wave energy excited by multiple scattering, we use the theoretical envelope synthesized on the basis of the radiative transfer theory as a Green's function. The site amplification factors are corrected considering the conservation of energy flux and using the coda normalization method. The inverted temporal energy release rate for the 2008 MW 6.9 Iwate-Miyagi Nairiku earthquake, Japan, decays following t-1.1, at the lapse time t of 40-900 s after the main shock origin time. This exponent of the decay rate is similar to the p value of the modified Omori law. The amount of estimated energy release is consistent with that calculated from the magnitude listed in the aftershock catalog. Although the uncertainty is large, the location of large energy release at the lapse times of 40-900 s approximately overlaps to that of the aftershocks, which surrounds the large energy release area during the main shock faulting. The maxima of the energy release rate normalized by the average decay rate distributes following a power law, similar to the Gutenberg-Richter law.

Sawazaki, Kaoru; Enescu, Bogdan

2014-06-01

12

Ruptured duodenal varices arising from the main portal vein successfully treated with endoscopic injection sclerotherapy: a case report.  

PubMed

Duodenal varices result from retroperitoneal portosystemic shunts that usually come from the pancreaticoduodenal vein and drain into the inferior vena cava. Because they are a rare but fatal cause of gastrointestinal bleeding, a prompt hemostatic intervention is mandatory. A 62-year-old man who had a history of excessive alcohol consumption presented with massive hematemesis and melena. Emergent endoscopy revealed ruptured varices with an adhering whitish fibrin clot on the postbulbar portion of the duodenum. Abdominal computed tomography demonstrated a cirrhotic liver with venous collaterals around the duodenum and extravasated contrast in the second and third portions. The collaterals originated from the main portal vein and drained via the right renal vein into the inferior vena cava. Endoscopic injection sclerotherapy with cyanoacrylate was successful in achieving hemostasis, and resulted in the near eradication of duodenal varices at a 6-month follow-up. PMID:21757987

Kang, Ha Yan; Lee, Won Kyung; Kim, Yong Hyun; Kwon, Byung Woon; Kang, Myung Soo; Kim, Suk Bae; Song, Il Han

2011-06-01

13

Investigation of seismicity after the initiation of a Seismic Electric Signal activity until the main shock.  

PubMed

The behavior of seismicity in the area candidate to suffer a main shock is investigated after the observation of the Seismic Electric Signal activity until the impending main shock. This is based on the view that the occurrence of earthquakes is a critical phenomenon to which statistical dynamics may be applied. In the present work, analysing the time series of small earthquakes, the concept of natural time chi was used and the results revealed that the approach to criticality itself can be manifested by the probability density function (PDF) of kappa(1) calculated over an appropriate statistical ensemble. Here, kappa(1) is the variance kappa(1)(=-(2)) resulting from the power spectrum of a function defined as Phi(omega)= summation operator(k=1)(N) p(k) exp(iomegachi(k)), where p(k) is the normalized energy of the k-th small earthquake and omega the natural frequency. This PDF exhibits a maximum at kappa(1) asymptotically equal to 0.070 a few days before the main shock. Examples are presented, referring to the magnitude 6 approximately 7 class earthquakes that occurred in Greece. PMID:18941306

Sarlis, N V; Skordas, E S; Lazaridou, M S; Varotsos, P A

2008-01-01

14

Thermal-Hydraulic Analyses of Steam Generator Tube Rupture Accident for the Kori Nuclear Unit 1 Pressurized Thermal Shock Study  

SciTech Connect

This paper discusses a thermal-hydraulic analysis methodology using RETRAN-3D and assembles system analyses for pressurized thermal shock resulting from a steam generator tube rupture accident in Kori Nuclear Unit 1. Through a systematic definition of sequences and thermal-hydraulic analyses using RETRAN-3D, the most important parameters on downcomer overcooling were identified. The break location that leads to the most significant overcooling was found to be the hot leg side in the loop that does not contain the charging flow inlet. The initial power level had a large effect on the downcomer overcooling. The closure failure of the pressurizer power operated relief valves and the termination failure of the safety injection were found to be the most significant operator actions. In contrast, auxiliary feedwater control failure had little effect on overcooling, and the steam dump valve closure failure merely resulted in a temperature rise in the latter half of the transient. Through these analyses, recommendations for sequence grouping and against downcomer overcooling are provided.

Hong, Soon-Joon [FNC Technology Company (Korea, Republic of); Kim, Jae-Hak [FNC Technology Company (Korea, Republic of); Kim, Yong-Soo [Seoul National University (Korea, Republic of); Park, Goon-Cherl [Seoul National University (Korea, Republic of)

2002-06-15

15

Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Main Shock Characteristics  

USGS Publications Warehouse

The October 17, 1989, Loma Prieta, Calif., earthquake (0004:15.2 G.m.t. October 18; lat 37.036? N., long 121.883? W.; 19-km depth) had a local magnitude (ML) of about 6.7, a surface-wave magnitude (MS) of 7.1, a seismic moment of 2.2x1019 N-m to 3.5x1019 N-m, a source duration of 6 to 15 s, and an average stress drop of at least 50 bars. Slip occurred on a dipping fault surface about 35 km long and was largely confined to a depth of about 7 to 20 km. The slip vector had a large vertical component, and slip was distributed in two main regions situated northwest and southeast of the hypocenter. This slip distribution caused about half of the earthquake's energy to be focused toward the urbanized San Francisco Bay region, while the other half was focused toward the southeast. Had the rupture initiated at the southeast end of the aftershock zone, shaking in the bay region would have been both longer and stronger. These source parameters suggest that the earthquake was not a typical shallow San Andreas-type event but a deeper event on a different fault with a recurrence interval of many hundreds of years. Therefore, the potential for a damaging shallow event on the San Andreas fault in the Santa Cruz Mountains may still exist.

Spudich, Paul, (Edited By)

1996-01-01

16

Main shock and aftershock records of the 1999 Izmit and Duzce, Turkey earthquakes  

USGS Publications Warehouse

The August 17, 1999 Izmit (Turkey) earthquake (Mw=7.4) will be remembered as one of the largest earthquakes of recent times that affected a large urban environment (U.S. Geological Survey, 1999). This significant event was followed by many significant aftershocks and another main event (Mw=7.2) that occurred on November 12, 1999 near Duzce (Turkey). The shaking that caused the widespread damage and destruction was recorded by a handful of accelerographs (~30) in the earthquake area operated by different networks. The characteristics of these records show that the recorded peak accelerations, shown in Figure 1, even those from near field stations, are smaller than expected (Çelebi, 1999, 2000). Following this main event, several organizations from Turkey, Japan, France and the USA deployed temporary accelerographs and other aftershock recording hardware. Thus, the number of recording stations in the earthquake affected area was quadrupled (~130). As a result, as seen in Figure 2, smaller magnitude aftershocks yielded larger peak accelerations, indicating that because of the sparse networks, recording of larger motions during the main shock of August 17, 1999 were possibly missed.

Celebi, M.; Akkar, S.; Gulerce, U.; Sanli, A.; Bundock, H.; Salkin, A.

2001-01-01

17

Slip rate, magnitudes and ages of surface-rupturing events along the Main Frontal Thrust in Bhutan (Himalaya)  

NASA Astrophysics Data System (ADS)

The Himalayas absorb about 20 mm.yr-1 of the convergence between India and Eurasia plate. Morphotectonics studies East of Bhutan yielded a Holocene shortening rate of 23 × 6.2 mm/yr consistent with the 21 × 1.5 mm/yr estimated in Nepal. Most of this crustal shortening is accommodated along the Main Frontal Thrust by major earthquakes (M?8) that occurred in the past 1000 years. Between 89°E and 92°E, the MFT runs along the southern border of the Kingdom of Bhutan where no reliable historical record of major earthquakes exists (one strong historical earthquake would have occurred in 1713 after a Tibetan eyewitness reports). However, recent paleoseismic investigations in Nepal and on both side of Bhutan border suggest that a great earthquake may have ruptured a 700 to 800 km long section of the MFT during a single event around AD 1100. In December 2012, we carried out a first morphotectonic and paleosismologic study within two sites (Sarpang, Gelephu) along the MFT in central Bhutan. We identified several sequences of abandoned fluvial terraces that have been uplifted along the fault. From a kinematic GPS survey, we estimated that the oldest terrace sequence (T2) has a cumulative offset of 53.6 × 2.3 m. A younger sequence (T1) shows offsets of 4.5 × 0.5 m on the lower terrace (T1a) and 7.9 × 0.5 m on the upper one (T1b). The uplift on T1b may cumulate the vertical components of the two last seismic events that would have produced each a vertical offset of several meters. These preliminary observations suggest that the latest seismic event as well as the penultimate event correspond to two major seismic events with magnitudes greater than M8. After 14C dating (charcoals in sands on top of T1 terraces sequence), these two last seismic events occurred after 1000 AD. The youngest event may correspond to the historical event reported in 1713 AD, while the penultimate event could correspond the great medieval earthquake observed in trenches East and West of Bhutan. After 10Be dating on T2 surface quartz rich cobbles, we estimate a vertical slip rate of 9.3 × 2.6 mm/yr along the MFT in Bhutan.

Ritz, J.; Berthet, T.; Ferry, M. A.; Pelgay, P.; Cattin, R.; Drukpa, D.; Braucher, R.; Chophel, J.; Thinley, K.; Hetényi, G.

2013-12-01

18

Shock  

MedlinePLUS

A person in shock has extremely low blood pressure. Depending on the specific cause and type of shock, symptoms will include one or more of the following: Anxiety or agitation/restlessness Bluish lips and fingernails Chest ...

19

Successful anesthetic management in a child after traumatic rupture of left main bronchus by a single-lumen cuffed-endotracheal tube.  

PubMed

Tracheobronchial injury (TBI) may lead to catastrophe if remains undetected or managed improperly. The incidence of TBI is less in children as compared with adults due to their pliable chest wall. Its clinical manifestations include persistent pneumothorax, cervical subcutaneous emphysema, pneumomediastinum, cyanosis, and respiratory insufficiency. The recommended airway management is to intubate the healthy bronchus with a single-lumen or double-lumen endotracheal tube (ET) and bypassing the injured side. We report successful anesthetic management of traumatic rupture of the left main bronchus in a child by using a single-lumen cuffed-ET. Many factors affect the outcome of such injuries and include the extent of the lesion, the resulting pulmonary status, the adequacy of surgical reconstruction. More severe injury may require lobectomy or pneumonectomy. Early diagnosis and proper management result in good functional outcome. PMID:25281627

Elgendy, Hamed; Jilani, Tariq

2014-01-01

20

Spontaneous rupture of a posttraumatic aneurysm of the axillary artery-a rare cause of hemorrhagic shock in children.  

PubMed

Posttraumatic aneurysms of the axillary artery are extremely scarce. In pediatrics, no similar case has been described. Injuries of axillary artery are often associated with ischemic complications, whereas the bleeding risks are not well documented. We report the case of a 5-year-old boy who was admitted with a scapular pulsatile lump 2 weeks after a domestic accident. During his stay, he suddenly presented a hemorrhagic shock. The patient was immediately admitted to the operating room to undergo surgical hemostasis and was then transferred to intensive care unit to stabilize his vital functions. This case shows the possibility of spontaneous and life-threatening acute bleeding of posttraumatic aneurysms of the axillary artery. PMID:24704582

Saad, Nabil; Bentalha, Aziza; Thar, Abdellatif; Benjelloun, Mohammed Younes; Oulahyane, Rachid; Mossadik, Ahlam; El Koraichi, Alae; El Kettani, Salma

2014-10-01

21

Shock  

MedlinePLUS

... can get to your organs and tissues. It causes very low blood pressure and may be life threatening. It often happens along with a serious injury. There are several kinds of shock. Hypovolemic ... Causes include internal or external bleeding, dehydration, burns, and ...

22

Vibration, acoustic, and shock design and test criteria for components on the Solid Rocket Boosters (SRB), Lightweight External Tank (LWT), and Space Shuttle Main Engines (SSME)  

NASA Technical Reports Server (NTRS)

The vibration, acoustics, and shock design and test criteria for components and subassemblies on the space shuttle solid rocket booster (SRB), lightweight tank (LWT), and main engines (SSME) are presented. Specifications for transportation, handling, and acceptance testing are also provided.

1984-01-01

23

Rupture process of the 2014 Iquique Chile Earthquake in relation with the foreshock activity  

NASA Astrophysics Data System (ADS)

rupture process of the 2014 Iquique, Chile earthquake is inverted from teleseismic P wave data applying a novel formulation that takes into account the uncertainty of Green's function, which has been a major error source in waveform inversion. The estimated seismic moment is 1.5 × 1021 Nm (Mw = 8.1), associated with a 140 km long and 140 km wide fault rupture along the plate interface. The source process is characterized by unilateral rupture propagation. During the first 20 s, the dynamic rupture front propagated from the hypocenter to the large asperity located about 50 km southward, crossing a remarkably active foreshock area at high velocity (of about 3.0 km/s), but small and irregular seismic moment release rate. Our result may suggest that the 20 s long initial phase was influenced by the stress drop due to the foreshock activity near the main shock hypocenter. Moreover, the 2 week long swarm-like foreshock activity migrating roughly at 5 km/day toward the main shock hypocenter, and possibly associated slow slip, contributed to the stress accumulation prior to the Mw 8.1 megaquake. The main shock initial rupture phase might have triggered the rupture of the large asperity, which had large fracture energy.

Yagi, Yuji; Okuwaki, Ryo; Enescu, Bogdan; Hirano, Shiro; Yamagami, Yuta; Endo, Suguru; Komoro, Takuya

2014-06-01

24

[Spontaneous splenic rupture due to heparin. Report of a case and review of the literature].  

PubMed

We describe in this report a case of spontaneous rupture of the spleen in a 68-year-old man on heparin therapy for cerebrovascular disease. This spontaneous splenic rupture is a rare complication of anticoagulant or thrombolytic therapy. Twenty cases were reported in the world medical literature. Only one case was due to heparin. The clinical presentation, which includes mainly abdominal and left shoulder pain with shock, could mimic cardiac diseases and delay or even mask the diagnosis. The mechanism of the rupture is still unknown. It is possible that altered hemostatic mechanisms may aggravate unrecognized micro trauma to provoke a rupture of the spleen. Once the rupture is suspected, the diagnosis can be confirmed with CT scan, or ultrasound. The treatment will be mainly reversal of anticoagulation and splenectomy. PMID:8965304

Jabbour, M; Tohmé, C; Ingea, H; Farah, P

1995-01-01

25

Soil gas distribution in the main coseismic surface rupture zone of the 1980, Ms = 6.9, Irpinia earthquake (southern Italy)  

NASA Astrophysics Data System (ADS)

gas measurements of different gas species with different geochemical behaviors were performed in the area of the Pecore Plain, a 200 m × 300 m sized, fault-bounded extensional basin located in the northern Mount Marzano massif, in the axial belt of the southern Apennine chain. The Pecore Plain area was affected by coseismic surface faulting during the Ms = 6.9, 1980 Irpinia earthquake, the strongest and most destructive seismic event of the last 30 years in southern Italy. The collected data and their geostatistical analysis provide new insights into the control exerted by active fault segments on deep-seated gas migration toward the surface. The results define anomalies that are aligned with the NW-SE trending coseismic rupture of the 1980 earthquake along the western border of the plain, as well as along the southern border of the plain where a hidden, E-W striking fault is inferred. Geospatial analysis highlights an anisotropic spatial behavior of 222Rn along the main NW-SE trend and of CO2 along the E-W trend. This feature suggests a correlation between the shape and orientation of the anomalies and the barrier/conduit behavior of fault zones in the area. Furthermore, our results show that gas migration through brittle deformation zones occurs by advective processes, as suggested by the relatively high migration rate needed to obtain anomalies of short-lived 222Rn in the soil pores.

Ciotoli, Giancarlo; Bigi, Sabina; Tartarello, Chiara; Sacco, Pietro; Lombardi, Salvatore; Ascione, Alessandra; Mazzoli, Stefano

2014-03-01

26

Fault branching and rupture directivity  

Microsoft Academic Search

Could the directivity of a complex earthquake be inferred from the ruptured fault branches it created? Typically, branches develop in forward orientation, making acute angles relative to the propagation direction. Direct backward branching of the same style as the main rupture (e.g., both right lateral) is disallowed by the stress field at the rupture front. Here we propose another mechanism

Sonia Fliss; Harsha S. Bhat; Renata Dmowska; James R. Rice

2005-01-01

27

Possible earthquake rupture speeds  

NASA Astrophysics Data System (ADS)

Though mode II shear fractures (primarily strike slip earthquakes) can not only exceed the shear wave speed of the medium, but can even reach the compressional wave speed, steady-state calculations showed that speeds between the Rayleigh and shear wave speeds were not possible, thus defining a forbidden zone. For more than 30 years it was believed that this result in which the rupture jumps over the forbidden zone, also holds for 3-D ruptures, in which mode II and mode III (mainly dip-slip faulting) are mixed. Using unprecedentedly fine spatial and temporal grids, we show that even in the simple configuration of homogeneous fault properties and linear slip-weakening friction law, a realistic 3-D rupture which start from rest and accelerates to some higher velocity, actually does pass smoothly through this forbidden zone, but very fast. The energy flux from the rupture tip is always positive, even within the so-called forbidden zone, contrary to the 2-D case. Finally, our results show that the width of the cohesive zone initially decreases, then increases as the rupture exceeds the shear wave speed and finally again decreases as the rupture accelerates to a speed of ~90% of the compressional wave speed. Several movies illustrating the development of the ruptures will be shown. A. Bizzari and S. Das (2012). Possible earthquake rupture speeds, EPSL, submitted.

Das, S.; Bizzarri, A.

2012-12-01

28

Shock, diaschisis and von Monakow.  

PubMed

The concept of shock apparently emerged in the middle of the 18th century (Whyett) as an occurrence observed experimentally after spinal cord transection, and identified as "shock" phenomenon one century later (Hall). The concept was extended (Brown-Séquard) and it was suggested that brain lesions caused functional rupture in regions distant from the injured one ("action à distance"). The term "diaschisis" (von Monakow), proposed as a new modality of shock, had its concept broadened, underpinned by observations of patients, aiming at distinguishing between symptoms of focal brain lesions and transitory effects they produced, attributable to depression of distant parts of the brain connected to the injured area. Presently, diaschisis is related mainly to cerebrovascular lesions and classified according to the connection fibers involved, as proposed by von Monakow. Depression of metabolism and blood flow in regions anatomically separated, but related by connections with the lesion, allows observing diaschisis with neuroimaging. PMID:23857617

Engelhardt, Eliasz; Gomes, Marleide da Mota

2013-07-01

29

AntiShock Garments for Obstetric Hemorrhage  

Microsoft Academic Search

Annually, over 500,000 women die from complications of pregnancy and childbirth; the majority die from hemorrhage and shock. Obstetrical hemorrhage of all etiologies, such as uterine atony, ruptured uterus, and ruptured ectopic, can cause massive blood loss resulting in severe shock. Unless women can access fluid replacement, blood transfusions, and, often, surgery, the shock leads to organ failure and death.

Suellen Miller; Aderinola Ojengbede; Janet Turan; Oladosu Ojengbede; Elizabeth Butrick; Paul Hensleigh

2007-01-01

30

The 1997 Umbria-Marche, Italy, earthquake sequence: a first look at the main shocks and aftershocks  

Microsoft Academic Search

A long sequence of earthquakes, six with magnitudes between 5 and 6, struck Central Italy starting on September 26, 1997, causing severe damages and loss of human lives. The seismogenic structure consists of a NW-SE elongated fault zone extending for about 40 km. The focal mechanisms of the largest shocks reveal normal faulting with NE-SW extension perpendicular to the trend

A. Amato; R. Azzara; C. Chiarabba; G. B. Cimini; M. Cocco; M. Di Bona; L. Margheriti; S. Mazza; F. Mele; G. Selvaggi; A. Basili; E. Boschi; F. Courboulex; A. Deschamps; S. Gaffet; G. Bittarelli; L. Chiaraluce; D. Piccinini; M. Ripepe

1998-01-01

31

Assessment of pH shock as a method for controlling sulfide and methane formation in pressure main sewer systems.  

PubMed

Caustic dosing to raise pH above 10.0 for short periods (hours) is often used by water utilities for controlling sulfide formation in sewers. However the effectiveness of this strategy is rarely reported and the impact of pH level and exposure time on the effectiveness is largely unknown. The effectiveness of this strategy under various pH levels (10.5-12.5) and exposure time (0.5-6.0 h) in controlling sulfide and methane production was evaluated in laboratory scale anaerobic sewer reactors and then in a real sewer system. Laboratory studies showed that the sulfide production rate of the laboratory sewer biofilm was reduced by 70-90% upon the completion of the pH shock, while the methane production rate decreased by 95-100%. It took approximately one week for the sulfate-reducing activity to recover to normal levels. In comparison, the methanogenic activities recovered to only about 10% in 4 weeks. The slow recovery is explained by the substantially loss of cell viability upon pH shocks, which recovered slowly after the shocks. Laboratory studies further revealed that a pH level of 10.5 for 1-2 h represent cost-effective conditions for the pH shock treatment. However, field trials showed a higher pH (11.5) and larger dosing times are needed due to the pH decreases along the sewer line and at the two ends of the caustic-receiving wastewater slugs due to dilution. To have effective sulfide and methane control, it is important to ensure effective conditions (pH > 10.5 and duration >1-2 h) for the entire sewer line. PMID:24210545

Gutierrez, Oriol; Sudarjanto, Gatut; Ren, Guo; Ganigué, Ramon; Jiang, Guangming; Yuan, Zhiguo

2014-01-01

32

Early second trimester uterine scar rupture.  

PubMed

Spontaneous uterine scar rupture can be lethal in pregnant women. A spontaneous uterine scar rupture in the early mid-trimester is rare and difficult to diagnose. This is a case of a 30-year-old woman (G2P1L1) at 19 weeks of gestation and having undergone a previous caesarean section presented with acute abdomen in shock. Laparotomy revealed a uterine scar rupture, which was resutured after evacuation of products of conception. This case merits that the uterine rupture should be considered as a differential diagnosis in pregnant women presenting with acute abdomen. In this case, although there was uterine rupture in the second trimester and a complete placental separation, fetus was alive which is quite unusual in patients presenting with rupture uterus. PMID:24326433

Bharatnur, Sunanda; Hebbar, Shripad; Shyamala, G

2013-01-01

33

Successful management of postinfarction ventricular septal rupture  

PubMed Central

Ventricular septal rupture is a rare but devastating complication of acute myocardial infarction. Especially in patients with cardiogenic shock, right ventricular dysfunction or an inferior infarct mortality is very high. We present a case in which an 83-year-old patient survived rupture of the ventricular septum complicating an inferior myocardial infarction. Unlike most patients his haemodynamic status did not deteriorate and delayed elective surgical repair was carried out successfully. ImagesFigure 1Figure 2

Swinkels, B.M.; Peters, R.H.J.; van den Brink, A.

2005-01-01

34

Spontaneous splenic rupture in a hemodialysis patient.  

PubMed

Spontaneous splenic rupture (SSR) in a patient undergoing hemodialysis has been described as an extremely rare and potentially fatal complication. We report here spontaneous splenic rupture in a 52-year-old woman undergoing regular hemodialysis for end-stage renal disease (ESRD). She complained of colicky abdominal pain in the left upper quadrant area and dizziness when she assumed an upright posture. Her vital signs revealed low blood pressure and tachycardia, which was suggestive of hypovolemic shock. Abdomen CT scan showed splenic hematoma and hemoperitoneum. However, she had no history of any event triggering the splenic rupture. An exploratory laparotomy showed a ruptured spleen and an emergency splenectomy was performed. We suggest that spontaneous spleen rupture may be attributed to uremic coagulopathy and heparin-induced coagulopathy. PMID:15988818

Kim, Hyun Jung; Lee, Gyeong Won; Park, Dong Jun; Lee, Jong Deog; Chang, Se Ho

2005-06-30

35

Earthquake Rupture Complexity Evidence from Field Observations (Invited)  

NASA Astrophysics Data System (ADS)

Field observations provide strong evidence for four intriguing aspects of rupture process complexity for the 4 April 2010 El Mayor - Cucapah - Indiviso earthquake. First, the southern “fork” of the rupture exhibits two splays just to the northwest of the event epicenter, both with nearly pure right-lateral faulting. Teleseismic source modeling by others indicates normal slip on deep fault surface preceded the shallow strike-slip faulting, and our field observations from the fork area indicate that the earliest phase of strike-slip faulting did not involve a significant normal faulting component. Second, as rupture propagated to the northwest along the Pescadores fault, slip ended abruptly on this fault and transferred across a complex zone to the Borrego fault (although the Pescadores fault continues farther and would have seemed an easier route to follow). This stepover is called the Puerta Accommodation Zone (PAZ) which extends 11 km along-strike within an elevated portion of the Cucapah massif and accommodates a left step (transpressional) that measures less than 2 km across-strike. Though partly obscured by rockfalls in the steep terrain here, only discontinuous faulting of up to one meter reached the ground surface, yet imagery differencing by others indicates several meters of continuous subsurface slip throughout this section. This 11 km region of reduced and discontinuous slip is one of the longest surface rupture jumps ever observed, with lengthy and continuous surface faulting on either side. The SE end of the stepover coincides spatially with the Canon Rojo embayment where the M7.2 1892 surface rupture propagated onto a second fault forming an abrupt corner in its surface trace. Hence, the surface rupture and slip distribution pattern in 2010 appears to have been influenced by stress changes induced by the 1892 event. Thirdly, from the NW end of the transition section, the Borrego fault continues to the NNW with strong east-down slip obliquity. Along this same reach of fault, the Laguna Salada fault was re-activated with minor west side down slip. Along the Paso Inferior accommodation zone, splays trending NNW to N had strong east-down slip, with right-lateral oblique motion. It was along this portion of the rupture that an eyewitness observed the rupture propagating from N to S, instead of in the expected S to N direction. Back-rupture may have resulted from triggered slip having raced ahead of the slower main rupture front, or may indicate a place where contiguous deep rupture ran out in front of shallow slip, or may result from the involvement here of the detachment fault system. Finally, in the northwestern portion of the rupture, from Paso Superior to the northwest of Cerro Centinela, a pattern of NE - SW oriented “cross faults” and N-S faults broke at the surface, in a manner similar to rupture that occurred in the Elmore Ranch Fault Zone during the Superstition Hills earthquake sequence of 1987. Unlike the Elmore Ranch event, however, there was no known main shock sub-event or any large aftershock that can be readily associated with the extensive cross-faulting that is observed in this case.

Hudnut, K. W.; Fletcher, J. M.; Rockwell, T. K.; Gonzalez-Garcia, J. J.; Teran, O.; Akciz, S. O.

2010-12-01

36

Self-Rupturing Hermetic Valve  

NASA Technical Reports Server (NTRS)

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

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

2011-01-01

37

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. PMID:2605439

Kaalund, S; Lass, P; Høgsaa, B; Nøhr, M

1989-01-01

38

Spontaneous Kidney Allograft Rupture  

Microsoft Academic Search

Spontaneous renal allograft rupture is one of the most dangerous complications of kidney transplantation, which can result in graft loss.This condition needs immediate surgical intervention. Conservative management has dismal results. Its prevalence varies from 0.3% to 3%. Rupture occurs in first few weeks after transplantation. Predisposing factors for graft rupture are acute rejection, acute tubular necrosis, and renal vein thrombosis.

H. Shahrokh; H. Rasouli; M. A. Zargar; K. Karimi; K. Zargar

2005-01-01

39

Focal mechanism distribution of main- and after- shock of the 2005 off Miyagi Earthquake (M7.2) by using radiation pattern of P- and S- wave  

Microsoft Academic Search

Interplate earthquakes of magnitude of 7.5 have occurred along the subduction plate boundary of the Miyagi-Oki region, middle part of the Japan Trench area, repeatedly on about 40 years intervals. In 2005, interplate earthquake with magnitude of 7.2 occurred in this area, considered to be the rupture of one of the asperities of the 1978 earthquake (M7.4) (Okada et al.,

K. Suzuki; R. Hino; Y. Yamamoto; Y. Ito; T. Kanazawa; T. Yamada; M. Shinohara; K. Uehira; M. Tanaka; Y. Kaneda

2007-01-01

40

Dynamic Interface Rupture in Extremely Heterogeneous Media  

NASA Astrophysics Data System (ADS)

Fracture experiments of monolithic brittle materials usually show the maximum speed of smooth rupture at some 30 % of the relevant shear wave speed. This experimental maximum rupture speed is by far lower than those predicted by theories and inferred from inversions of seismograms, and some seismic inversions (e.g., the 1979 Imperial Valley, 1992 Landers, 1999 Izmit, 2001 the central Kunlunshan and 2002 Denali earthquakes) even suggest the existence of supershear rupture speeds (i.e., rupture propagating faster than the relevant shear wave). Recently, Uenishi et al. ( SSJ Fall Meeting, 2004, 2005; AGU Fall Meeting, 2006) experimentally investigated dynamic fracture in monolithic hyperelastic materials under static mode-§ loading conditions with relatively high crack-parallel stresses. Using a high-speed digital video camera system, they showed that cracks may propagate supersonically even in homogeneous materials. However, the exact mechanism for rupture nucleation and the transition of a nucleated rupture from sub-Rayleigh to super-shear rupture speed has not been identified yet. In this contribution, we further develop our experimental system and investigate dynamic fracture in extremely heterogeneous media, consisting of thin fluid and solid films: Inside a wire frame (50mm high, 50mm wide), a flat soap film contacts a flat thin solid plastic film (20mm high, 20mm wide), under static tensile loading conditions. The rupture (crack), initiated at a point, propagates subsonically in the linear elastic fluid film (see e.g., Uenishi et al., SSJ Fall Meeting, 2006, for the dynamic rupture in monolithic fluid films). When the circular rupture front reaches the interface, the rupture advances along the interface and then it is "diffracted" at the two corners of the interface. We record the rupture propagation process utilizing our high-speed digital video camera at a frame rate of 20 ?s (20×10-6s). The observed results show that interface rupture propagation may accelerate (or even decelerate) and the dynamic rupture behavior is very sensitive to the geometry of the interface between the two films: (1) When the subsonic rupture front reaches the first rectangular corner, it accelerates around the corner and then advances supersonically along the interface; and (2) when the supersonic interface rupture front approaches the second corner (obtuse with respect to the rupture front in fluid), it bifurcates for a short period (400 ?s): the first branch unexpectedly expands rather straight into the bulk and the second one propagates along the interface at a lower speed; At a later stage, again unexpectedly, the first branched crack decelerates significantly in the bulk and the two cracks eventually merge into a single crack. The overall behavior is - in some sense - similar to that of the oblique shock and Prandtl- Meyer expansion waves in fluid mechanics, and it might give new insights not only into the question of high rupture speeds of natural earthquakes but also into the generation mechanism of tsunamis. u.ac.jp/~uenishi/

Uenishi, K.; Tsuji, K.

2007-12-01

41

Toward resolving stable high-resolution kinematic rupture models of large earthquakes by joint inversion of seismic, geodetic and tsunami observations  

NASA Astrophysics Data System (ADS)

In this thesis, I summarize the research that I have done at UC Santa Cruz involving my development of joint inversion approaches using hr-GPS, teleseismic body and surface waves, regional seismic, campaign GPS, InSAR and tsunami datasets, to investigate the kinematic rupture patterns of large earthquakes. In eight different studies of rupture models of the 2011 Tohoku earthquake, 2012 Indo-Australia earthquake, 2012 Costa Rica earthquake, 2013 Craig earthquake, 2010 Mentawai earthquake, 2013 Pakistan earthquake, 2010 Chile earthquake and 2014 Iquique earthquake, I adopted each available dataset progressively in my joint inversion algorithm, so that in my current approach I can model all of the types of datasets simultaneously. As noted in this thesis, the teleseismic datasets provide good temporal resolution of the rupture process, while geodetic datasets have good spatial resolution. Tsunami datasets have good spatial resolution of slip near the trench. The joint inversion combines the advantage of each dataset, yielding stable and high- resolution rupture models with detailed spatial and temporal information. Resolving a robust and detailed rupture model helps us to understand co-seismic rupture properties, such as depth dependent energy release patterns, super-shear rupture, and tsunami excitation. Comparing the inter-seismic locking pattern and post-seismic stress release pattern with the co-seismic rupture model helps to investigate the locking and releasing behavior of the fault plane through the earthquake cycle, the stress release level of large earthquakes and the relationship between the main shock ruptures, aftershocks and non-seismogenic deformation.

Yue, Han

42

Physiopathology of shock  

PubMed Central

Shock syndromes are of three types: cardiogenic, hemorrhagic and inflammatory. Hemorrhagic shock has its initial deranged macro-hemodynamic variables in the blood volume and venous return. In cardiogenic shock there is a primary pump failure that has cardiac output/mean arterial pressure as initial deranged variables. In Inflammatory Shock it is the microcirculation that is mainly affected, while the initial deranged macrocirculation variable is the total peripheral resistance hit by systemic inflammatory response. PMID:21769210

Bonanno, Fabrizio Giuseppe

2011-01-01

43

[Massive hemoperitoneum from rupture of an intra-peritoneal varix].  

PubMed

Rupture of an intra-abdominal varix in a patient with portal hypertension is a rare but severe cause of massive hemoperitoneum. The authors report the case of a patient with alcoholic cirrhosis that presented to the emergency department with hypovolemic shock. Imaging showed massive hemoperitoneum, severe portal hypertension and suggested the diagnosis of spontaneous rupture of an intra-abdominal varix, confirmed at laparotomy. PMID:12469017

Léauté, F; Frampas, E; Mathon, G; Leborgne, J; Dupas, B

2002-11-01

44

The Constantine (northeast Algeria) earthquake of October 27, 1985: surface ruptures and aftershock study  

NASA Astrophysics Data System (ADS)

An earthquake of magnitude M s = 6.0 (CSEM, Strasbourg) occurred at Constantine (Algeria) on 27 October 1985. This seismic event is the strongest felt in the Tellian Atlas since the El Asnam seismic crisis of October 10, 1980. A team from the Centre de Recherche d'Astronomie, d'Astrophysique et de Géophysique (CRAAG, Algeria), utilising 8 portable stations, registered the activity a few days after the main shock. The aftershocks follow a N045° direction, and show the existence of three ruptured segments. Cross sections display a remarkable vertical fault plane and suggest asperities in the rupture process. Surface breaks were found affecting Quaternary deposits. The principal segment is about 3.8 km long showing "enéchelon" cracks with left-lateral displacement while the main direction of the rupture is N055°. Although the vertical motion is small, the northwestern block shows a normal component of the main surface faulting, while the left-lateral displacement is about 10 cm. The strike-slip focal mechanism solution determined from the global seismic network and field observations are in good agreement.

Bounif, A.; Haessler, H.; Meghraoui, M.

1987-10-01

45

Ruptured ulnar artery pseudoaneurysm  

Microsoft Academic Search

Ulnar artery aneurysms and pseudoaneurysms are rare lesions that usually occur distal to the wrist and cause symptoms as a result of embolization and not rupture. An elderly woman presented with acute rupture of an ulnar artery pseudoaneurysm proximal to the wrist, which caused severe neurologic compromise as a result of bleeding into Guyon's canal and the carpal tunnel. The

Luke S. Erdoes; William C. Brown

1995-01-01

46

Simulations of Relativistic Collisionless Shocks: Shock Structure and Particle Acceleration  

SciTech Connect

We discuss 3D simulations of relativistic collisionless shocks in electron-positron pair plasmas using the particle-in-cell (PIC) method. The shock structure is mainly controlled by the shock's magnetization (''sigma'' parameter). We demonstrate how the structure of the shock varies as a function of sigma for perpendicular shocks. At low magnetizations the shock is mediated mainly by the Weibel instability which generates transient magnetic fields that can exceed the initial field. At larger magnetizations the shock is dominated by magnetic reflections. We demonstrate where the transition occurs and argue that it is impossible to have very low magnetization collisionless shocks in nature (in more than one spatial dimension). We further discuss the acceleration properties of these shocks, and show that higher magnetization perpendicular shocks do not efficiently accelerate nonthermal particles in 3D. Among other astrophysical applications, this may pose a restriction on the structure and composition of gamma-ray bursts and pulsar wind outflows.

Spitkovsky, Anatoly; /KIPAC, Menlo Park

2006-04-10

47

Rupture zones of great earthquakes in the alaska-aleutian arc, 1784 to 1980.  

PubMed

Historical documents indicate that great earthquakes ruptured at least a 500-kilometer-long segment of the plate boundary near the Alaska Peninsula in 1788 and 1847. At least half of a major seismic gap in the Shumagin Islands ruptured during those shocks but has not experienced a great earthquake for at least 77 years. Large shocks along this and other plate boundaries occur in bursts followed by several decades during which there is very little energy release. PMID:17817844

Sykes, L R; Kisslinger, J B; House, L; Davies, J N; Jacob, K H

1980-12-19

48

A case of papillary muscle rupture caused by acute myocardial infarction.  

PubMed

A 63-year-old female was admitted because of cardiogenic shock due to complete rupture of the posterior papillary muscle. The diagnosis was made by echocardiography. She was treated successfully by an emergency replacement of the mitral valve. Early diagnosis and surgical treatment are mandatory and life-saving in the case of complete papillary muscle rupture. PMID:11958276

Morishita, S; Fujinaga, H; Nakayama, T; Kujime, S; Uehara, K; Kimura, M; Chikamori, K; Izumi, S; Nishimura, T; Tano, K

2001-01-01

49

Delivery related rupture of the gravid uterus: imaging findings: a case report  

Microsoft Academic Search

Rupture of the gravid uterus is a rare, life-threatening obstetric complication. Major symptoms are hypovolemic shock and abdominal pain during late pregnancy or after vaginal delivery. Immediate surgical therapy is required. We report a case of uterine rupture after vaginal delivery diagnosed by means of ultrasonography and computed tomography.

F. Catry; E. Geusens; D. Vanbeckevoort; W. Volders; D. Bielen; B. Spitz

2004-01-01

50

Non-bleeding Spontaneous Rupture of Hepatocellular Carcinoma.  

PubMed

Rupture of hepatocellular carcinoma (HCC) is not uncommon and most ruptured HCC present with hemoperitoneum and hemorrhagic shock. Management of ruptured HCC is different than non-ruptured one. Short- and long-term mortality increases following rupture of HCC with increasing chances of tumor dissemination. We describe a case with non-bleeding spontaneous rupture of HCC. A 62-year-old male patient was admitted to our institute hospital with mild to moderate pain in the right upper part of the abdomen. He lost appetite and weight. Ultrasonography of the abdomen was performed and it suggested HCC and ascites. Triple phase computer tomography revealed HCC in segments 6 and 7 of liver with typical radiological characteristics. Portal vein was thrombosed. No extravasation of dye was seen. Ruptured of tumor through liver capsule was seen with necrosis and hemorrhage in the center of the tumor. Non-bleeding ruptured HCC has not been reported in the literature to the best of our knowledge. We herein describe this rare case. PMID:24497757

Islam, Mahibul; Deka, Pranjal; Kapur, Raj; Ansari, Md Abu Masud

2013-07-01

51

[Bilateral uterine rupture of an unscarred gravid uterus before labor].  

PubMed

We report a case of bilateral spontaneous uterine rupture of an unscarred uterus occured in a primigravida at 32 weeks to take care in our department after in utero transfert. Uterine rupture occurs mainly on scarred uterus during labor. This is an unfrequent but serious complication involving fetal-maternal prognosis in the absence of immediate care. We are conducting a review about spontaneous uterine rupture of unscarred uterus, before and during labor. PMID:24394323

Leroux, M; Coatleven, F; Faure, M; Horovitz, J

2014-06-01

52

Coseismic Fault Slip Rupture from the Joint Inversion of Teleseismic, Local Strong-Motion and CGPS Related to the 2010 Jia-Shian Earthquake in Southwestern Taiwan  

NASA Astrophysics Data System (ADS)

The Jia-Shian earthquake (Mw=6.3) occurred on 04th March 2010 in the southwestern Taiwan. We used the waveforms of teleseismics to identify the strike, dip and rake of focal mechanism are 311/33/37. Furthermore, we explored the strike, dip and rake are 316/40/44 on the first pulse of the teleseismic P wave. We also took account of the Continuous Global Positioning System (CGPS) data for the coseismic offset. The maximum horizontal and vertical (uplift) of coseismic offsets at the surface are 29.8mm± 1.0mm and 30.6mm± 5.1mm, respectively at station GS51. Moreover, the space and time distribution of slip during the coseismic rupture was modeled by the joint inversion, which includes the CGPS coseismic offset, the teleseismic, and near field seismic records. We identified the faults geometry and reconstructed the rupture process of coseismic faults slip. The initial rupture was generated on the northwest - southeast trending fault and propagated to the northeast - southwest trending structure after 5 s of main shock. Their strike, dip and rake are 311/33/37 and 020/25/108, respectively. The average slip of rupture was 20.1 cm, with the maximum slip of 50.4 cm. The rupture of the seismic moment was 4.0 × 10 ^ 25 dyne-cm in 30 s of duration time.The slip rupture constrained the synthetic data quite well, especially for the CGPS coseismic offset. We inferred the Jia-Shian earthquake took place on blind fault and the northeast - southwest trending structure was activated following the rupture on main northwest - southeast trending fault.

Lin, Kuan-Chuan; Delouis, Bertrand; Hu, Jyr-Ching; Nocquet, Jean-Mathieu; Mozziconacci, Laetitia; Bethoux, Nicole

2013-04-01

53

Placenta Accreta Causing Uterine Rupture in Second Trimester of Pregnancy after in vitro Fertilization: A Case Report  

PubMed Central

Background Placenta accreta is a rare obstetrical condition that mainly occurs in the third trimester leading to life-threatening complications. Hereby, a case of uterine rupture due to placenta accreta occuring in the second trimester is presented. Case Presentation A forty-year old patient who conceived after in vitro fertilization treatment (oocyte donation and embryo transfer) presented in emergency department in the nineteen weeks of gestation with acute abdominal pain, heamoperitoneum and fetal death. Emergency laprotomy showed uterine rupture along with placenta accreta for which the patient underwent subtotal hysterectomy. Conclusion Although, an uncommon occurrence, physicians in assisted reproductive techniques (ART) clinics should consider placenta accreta in gravid patients who present with acute abdominal pain and shock, considering the fact that they usually have associated high risk factors for abnormal placentation. PMID:23926525

Dahiya, Priya; Nayar, Kanad D.; Gulati, Amar J.S.; Dahiya, Kiran

2012-01-01

54

Complicated malaria and a covert ruptured spleen: a case report.  

PubMed

Spontaneous splenic rupture in complicated malaria is an uncommon cause of hemoperitoneum in the tropics. The exact incidence of splenic rupture is unknown, largely due to under-reporting, but has been estimated at ?2%. Its pathophysiology is linked to the formation of a subcapsular hematoma. Upon rupture, patients present with features of shock and peritonitis and in most cases (95%), computed tomography (CT) scan detects the splenic injury. Patients should be managed conservatively with splenectomy reserved for patients with shock and hemoperitoneum due to risk of post-splenectomy sepsis. We report the case of a 38-year-old man with severe malaria who presented with fever, chills and abdominal pains. A CT scan abdomen failed to reveal splenic parenchymal injury or any splenic extravasation of contrast. Conservative management was unsuccessful. Exploratory laparatomy confirmed the spleen as the site of bleeding necessitating a splenectomy. PMID:25395608

Waweru, Peter; Macleod, Jana; Gikonyo, Anthony

2014-01-01

55

Complicated malaria and a covert ruptured spleen: a case report  

PubMed Central

Spontaneous splenic rupture in complicated malaria is an uncommon cause of hemoperitoneum in the tropics. The exact incidence of splenic rupture is unknown, largely due to under-reporting, but has been estimated at ?2%. Its pathophysiology is linked to the formation of a subcapsular hematoma. Upon rupture, patients present with features of shock and peritonitis and in most cases (95%), computed tomography (CT) scan detects the splenic injury. Patients should be managed conservatively with splenectomy reserved for patients with shock and hemoperitoneum due to risk of post-splenectomy sepsis. We report the case of a 38-year-old man with severe malaria who presented with fever, chills and abdominal pains. A CT scan abdomen failed to reveal splenic parenchymal injury or any splenic extravasation of contrast. Conservative management was unsuccessful. Exploratory laparatomy confirmed the spleen as the site of bleeding necessitating a splenectomy.

Waweru, Peter; Macleod, Jana; Gikonyo, Anthony

2014-01-01

56

Evidence for Coseismic Rupture Beyond the Base of the Seismogenic Layer  

NASA Astrophysics Data System (ADS)

For scientific reasons and hazard assessment it is important to better understand the physics and rupture characteristics of large, destructive earthquakes. However, those events occur infrequently, severely obstructing their analysis. Smaller but more frequent earthquakes are usually studied and their characteristics are extrapolated to assess large earthquake behavior, assuming that small and large events are associated with the same physical processes and parameters. For small and moderate size earthquakes it was observed and independently derived from elastic models that coseismic stress drop is independent of earthquake size and that slip is proportional to the smallest rupture dimension. It is therefore assumed that large earthquake stress drops are essentially equal to the stress drop of their smaller size siblings. It is further assumed that the slip amount of large events does not further increase once it ruptures the full seismogenic layer--the base of the seismogenic layer is commonly thought to limit the earthquake down-dip rupture extend and thus defines the smallest rupture dimension. However, slip observations for many large strike-slip events show how offset gradually increases with rupture length. Two explanations have been formulated: If the rupture width of those events were indeed limited by the base of the seismogenic layer, the observations would imply larger stress drops and possibly other processes involved in large earthquake rupture, questioning the validity of the aforementioned extrapolation from small to large earthquakes. On the other hand, if rupture width of large earthquakes were not limited by the base of the seismogenic layer but were allowed to extend further down (as suggested by recent studies), the increased slip amount may be explained without an increase in stress drop or additional rupture mechanisms for large earthquakes. For the study we present here, we analyzed seismic data constraining the depth extent of large earthquakes relative to the depth of the seismogenic base. We utilized time series data of aftershock depths for a number of large strike-slip earthquakes, generating aftershock time vs. depth histograms to investigate the temporal variation in depth distribution. Based on hypocenter depth of small earthquakes along the Landers fault (causing the 1992 M7.3 Landers earthquake), we identified the base of the seismogenic layer at ~10km. Aftershocks that occurred only days after the Landers earthquake had maximum depths of ~18km, suggesting that rupture of the main shock extended this far down and therefore went well below the base of the seismogenic layer. Maximum aftershock depth then decayed roughly logarithmically, reaching the previous value of ~10km after about 5.5years. We argue that these observations are a logical consequence of the visco-elastic rheology of crustal rocks: Coseismically highly increased strains elevate the crustal stiffness, temporarily lowering the base of the seismogenic layer and permitting initiation of slip instabilities at depths that are otherwise characterized by viscous behavior. Extrapolation from small to large earthquakes is therefore permitted. No additional stress drop or rupture mechanism is required to explain the data.

Zielke, O.; Wesnousky, S.

2010-12-01

57

Analysis of Main-Steam-Line-Break Accidents Using RETRAN-3D for Pressurized Thermal Shock Evaluation of the Kori Nuclear Unit-1 Power Plant  

SciTech Connect

A thermal-hydraulic analysis methodology is established for a pressurized thermal shock (PTS) analysis of the Kori Nuclear Unit-1 (KNU-1) power plant using RETRAN-3D. The effects of the important parameters on PTS are evaluated, such as the initial power level, break size, isolation of the depressurized steam generator (SG), and charging flow runback. As a result, the most dominant factors are revealed as the initial power level and break flow rate. Auxiliary feedwater (AFW) to the depressurized SG should be isolated by operator action as soon as possible to minimize break flow. To mitigate the risk of PTS by reducing both steam flow rate and operator response time of depressurized SG isolation, the installation of check valves to block the cross flow between two steam lines is recommended. An efficient grouping methodology is proposed using these results. Groups should be divided according to the break size, the initial power level, and the AFW isolation to a depressurized SG. Charging flow runback is revealed to have little effect on downcomer overcooling.

Kim, Jae-Hak [Seoul National University (Korea, Republic of); Hong, Soon-Joon [Seoul National University (Korea, Republic of); Park, Goon-Cherl [Seoul National University (Korea, Republic of); Kim, Yong-Soo [Korea Electric Power Cooperation (Korea, Republic of)

2000-11-15

58

The resolution of ruptures in the therapeutic alliance  

Microsoft Academic Search

This article outlines some of the main features of a research program on ruptures in the therapeutic alliance and reports some of the major findings to date. A rupture in the therapeutic alliance is a deterioration in the quality of the relationship between patient and therapist; it is an interpersonal marker that indicates a critical opportunity for exploring and understanding

Jeremy D. Safran; J. Christopher Muran

1996-01-01

59

DIFFUSIVE SHOCK ACCELERATION AT COSMOLOGICAL SHOCK WAVES  

SciTech Connect

We reexamine nonlinear diffusive shock acceleration (DSA) at cosmological shocks in the large-scale structure of the universe, incorporating wave-particle interactions that are expected to operate in collisionless shocks. Adopting simple phenomenological models for magnetic field amplification (MFA) by cosmic-ray (CR) streaming instabilities and Alfvenic drift, we perform kinetic DSA simulations for a wide range of sonic and Alfvenic Mach numbers and evaluate the CR injection fraction and acceleration efficiency. In our DSA model, the CR acceleration efficiency is determined mainly by the sonic Mach number M{sub s} , while the MFA factor depends on the Alfvenic Mach number and the degree of shock modification by CRs. We show that at strong CR modified shocks, if scattering centers drift with an effective Alfven speed in the amplified magnetic field, the CR energy spectrum is steepened and the acceleration efficiency is reduced significantly, compared to the cases without such effects. As a result, the postshock CR pressure saturates roughly at {approx}20% of the shock ram pressure for strong shocks with M{sub s} {approx}> 10. In the test-particle regime (M{sub s} {approx}< 3), it is expected that the magnetic field is not amplified and the Alfvenic drift effects are insignificant, although relevant plasma physical processes at low Mach number shocks remain largely uncertain.

Kang, Hyesung [Department of Earth Sciences, Pusan National University, Pusan 609-735 (Korea, Republic of)] [Department of Earth Sciences, Pusan National University, Pusan 609-735 (Korea, Republic of); Ryu, Dongsu, E-mail: kang@uju.es.pusan.ac.kr, E-mail: ryu@canopus.cnu.ac.kr [Department of Astronomy and Space Science, Chungnam National University, Daejeon 305-764 (Korea, Republic of)] [Department of Astronomy and Space Science, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

2013-02-10

60

Imaging gate oxide ruptures  

Microsoft Academic Search

As minimum feature sizes are reduced in MOS silicon devices, dielectric breakdown continues to pose a formidable challenge. A more complete understanding of the failure mechanism which induces oxide rupture has become an absolute necessity in order to meet the advancing yield and reliability requirements of today's complex integrated structures. This paper will present an interesting insight into the nature

Horacio Mendez; Steve Morris; Sudhindra Tatti; Nicholas Dickson; Ronald E. Pyle

1993-01-01

61

Bipolar infrapatellar tendon rupture.  

PubMed

Traumatic patella alta in children occurs either distal to the patellar tendon as a tibial tubercle apophyseal fracture or proximally as an osteochondral sleeve fracture of the inferior patellar pole. Acute surgical exploration in a pediatric case of a knee extensor mechanism rupture revealed both proximal and distal (bipolar) patellar tendon pathology. PMID:7790483

Berg, E E

1995-01-01

62

Laser measurements of bacterial endospore destruction from shock waves  

NASA Astrophysics Data System (ADS)

The effects of shock waves on bioaerosols containing endospores were measured by combined laser absorption and scattering. Experiments were conducted in the Stanford aerosol shock tube for post-shock temperatures ranging from 400 K to 1100 K. Laser intensity measurements through the test section of the shock tube at wavelengths of 266 and 665 nm provided real-time monitoring of the morphological changes (includes changes in shape, structure and optical properties) in the endospores. Scatter of the visible light measured the integrity of endospore structure, while absorption of the UV light provided a measure of biochemicals released when endospores ruptured. For post-shock temperatures above 750 K the structural breakdown of Bacillus atrophaeus (BA) endospores was observed. A simple theoretical model using laser extinction is presented for determining the fraction of endospores that are ruptured by the shock waves. In addition, mechanisms of endospore mortality preceding their disintegration due to shock waves are discussed.

Lappas, Petros P.; McCartt, A. Daniel; Gates, Sean D.; Jeffries, Jay B.; Hanson, Ronald K.

2013-12-01

63

[Splenic artery rupture in pancreatic pseudocyst].  

PubMed

Hemorrhage is one of the most threatening complication of pancreatic pseudocyst. It results from erosion of adjacent vessels. Splenic, gastroduodenal, pancreaticoduodenal and middle colic vessels are predominantly involved. Hemorrhage may present different feature: intra and/or extraperitoneal collection, gastrointestinal bleeding. The authors report the rupture of splenic artery into pseudocyst, with the formation of pulsating pseudoaneurysm, increasing progressively until the final rupture. For the diagnosis the authors utilized: ultrasounds (US) which showed the cyst but not its nature and content; the CT scan which disclosed haematic contents; finally the US Color Doppler which proved the dynamic feature of hemorrhage. This technique allows to identify the arterious or venous source of bleeding and the possible presence of arteriovenous fistula. Arteriography was not performed due to circumstances, although it would permit bleeding vessel embolization and the control of hemorrhage. This procedure is not ever achievable, and doesn't exclude the possibility of rebleeding. On surgery, since the intraoperative rupture of the pseudoaneurysm occurred with severe hypovolemic shock, only a timely posterior mesogastric mobilization and the medially displacement of spleen-body-tail pancreatic complex, allowed to clamp the mass and the hemostasis. When such lesion are approached, it is mandatory to be prepared to carry on this maneuver: the severity of bleeding cannot allow intracystic ligature of bleeding vessel. PMID:10920499

Ungania, S; Panocchia, N

2000-01-01

64

[Traumatic rupture of the descending aorta].  

PubMed

During a ten-year period 16 patients were seen with aortic rupture and false aneurysm secondary to blunt trauma. One patient underwent an acute operation, 4 patients had operative therapy elective delayed and 11 patients were operated on for chronic traumatic false aneurysm. Operative delay was done in case of simultaneous multisystem injury (e.g. shock caused by abdominal injuries, cerebral contusion or pulmonary contusion on the right side). The shunt bypass method of repair was used in the case of 3 patients, cardiopulmonary bypass in 6 cases and simple aortic cross-clamping in 6 patients. One operation was performed without aortic cross-clamping. Primary repair was achieved in three patient, in 3 more cases a patch was inserted and in 9 cases interposition Dacron grafting was accomplished. One "wrapping" operation was performed. In 2 cases, reoperation was necessary because of postoperative bleeding. One patient died in the perioperative period. Right sided hemiparesis occurred in one patient postoperatively. Rupture does not affect the whole aortic wall, especially in young people because of the natural elasticity of vessel. The appearing shock and hypotension might protect the mediastinal pleura against bursting. This could provide a chance to survive. Our experience indicate: Elective delay of operation in patients with multiple system injuries can be achieved with antihypertensive therapy. PMID:9380385

Kovács, E; Dzsinich, C; Gyöngy, T; Moravcsik, E; Szabolcs, Z; Bodor, E

1997-09-28

65

The Constantine (Algeria) seismic sequence of 27 October 1985: a new rupture model from aftershock relocation, focal mechanisms, and stress tensors  

NASA Astrophysics Data System (ADS)

The October 27, 1985 Constantine earthquake of magnitude MS 5.9 (NEIC) although moderate is the strongest earthquake recorded in the eastern Tellian Atlas (northeast Algeria) since the beginning of instrumental seismology. The main shock locations given by different institutions are scattered and up to 10 km away northwest from the NE-SW 30 km long elongated aftershocks cloud localized by a dedicated temporary portable network. The focal mechanism indicates left-lateral strike-slip on an almost vertical fault with a small reverse component on the northwest dipping plane. This paper presents relocations of the main shock and aftershocks using TomoDD. One hundred thirty-eight individual focal mechanisms have been built allowing the determination of the stress tensor at different scales. A rupture model has been suggested, which explains the different observations of aftershock distribution and stress tensor rotation.

Ousadou, F.; Dorbath, L.; Dorbath, C.; Bounif, M. A.; Benhallou, H.

2013-04-01

66

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

67

Iatrogenic tracheobronchial rupture  

PubMed Central

Abstract Iatrogenic tracheobronchial ruptures most frequently occur during tracheal intubation, but they can also be produced during tracheobronchial endoscopy or thoracic surgery. The clinical presentation can be brutal, with respiratory failure, cervical emphysema, pneumothorax and hemoptysis. There are also less symptomatic presentations. The diagnosis is confirmed by bronchoscopy. The therapeutic approach can be differentiated, surgical or conservative, although the criteria are not universally accepted. This article aims to review the indications and therapeutic options. PMID:25408752

Paraschiv, M

2014-01-01

68

Ruptured giant right coronary artery aneurysm percutaneously plugged.  

PubMed

The endovascular management of a patient with a ruptured giant coronary aneurysm presenting with chest pain followed by anterior chest wall ecchymosis and shock is described. The inflow to a large, acutely leaking right coronary aneurysm was successfully sealed with the Amplatzer Vascular Plug device. The patient was estimated to be at very high risk for surgical intervention. The use of this device to seal an acutely leaking coronary aneurysm has not been previously described. PMID:17341782

Hillegass, William B; Gupta, Himanshu; Katragadda, Raghunath; Knoblauch, Johnnie; Coghlan, Cecil; Misra, Vijay K

2007-03-01

69

Bond-rupture immunosensors--a review.  

PubMed

It has long been the goal of researchers to develop fast and reliable point-of-care alternatives to existing lab-based tests. A viable point-of-care biosensor is fast, reliable, simple, cost-effective, and detects low concentrations of the target analyte. The target of biosensors is biological such as bacteria or virus and as such, the antibody-antigen bond derived from the real immune response is used. Biosensor applications include lab-based tests for the purposes of diagnostics, drug discovery, and research. Additional applications include environmental, food, and agricultural monitoring. The main merits of the bond-rupture method are quick, simple, and capable of discriminating between specific and non-specific interactions. The separation of specific and non-specific bonds is important for working in real-life complex serums such as blood. The bond-rupture technique can provide both qualitative results, the detection of a target, and quantitative results, the concentration of target. Bond-rupture achieves this by a label-free method requiring no pre-processing of the analyte. A piezoelectric transducer such as the quartz crystal microbalance (QCM) shakes the bound particles free from the surface. Other transducers such as Surface Acoustic Wave (SAW) are also considered. The rupture of the bonds is detected as electronic noise. This review article links diverse research areas to build a picture of a field still in development. PMID:18343101

Hirst, Evan R; Yuan, Yong J; Xu, W L; Bronlund, J E

2008-07-15

70

Acoustic-Friction Networks and the Evolution of Precursor Rupture Fronts in Laboratory Earthquakes  

PubMed Central

The evolution of shear rupture fronts in laboratory earthquakes is analysed with the corresponding functional networks, constructed over acoustic emission friction-patterns. We show that the mesoscopic characteristics of functional networks carry the characteristic time for each phase of the rupture evolution. The classified rupture fronts in network states–obtained from a saw-cut fault and natural faulted Westerly granite - show a clear separation into three main groups, indicating different states of rupture fronts. With respect to the scaling of local ruptures' durations with the networks' parameters, we show that the gap in the classified fronts could be related to the possibility of a separation between slow and regular fronts.

Ghaffari, H. O.; Young, R. P.

2013-01-01

71

Anaphylactic Shock During Pulmonary Hydatid Cyst Surgery  

PubMed Central

Introduction: Hydatid cyst is a parasitic disease caused by a tapeworm Echinococcusgranulosus. Humans are accidental hosts and infected after digestion of foods contaminated to fecal matter of definite hosts. The most affected organs are liver and lungs. Rupture of cyst (spontaneous rupture or rupture due to trauma or surgery) can cause anaphylactic reactions. Even considered as a rare event during anesthesia, it can be life threatening with the manifestations of severe hypotension and circulatory shock. Thus, immediate and proper treatment is necessary . Case Presentation: We report a case of anaphylactic shock during surgery of pulmonary Hydatid cyst in a 42 year old woman and its management. Conclusions: During the surgery of hydatid cyst, any hemodynamic instability should raise the suspension of anaphylaxis and early resuscitation should be instituted.

Marashi, Shaqayeq; Hosseini, Vahideh Sadat; Saliminia, Alireza; Yaghooti, Amirabbas

2014-01-01

72

Slow rupture of frictional interfaces  

NASA Astrophysics Data System (ADS)

The failure of frictional interfaces and the spatiotemporal structures that accompany it are central to a wide range of geophysical, physical and engineering systems. Recent geophysical and laboratory observations indicated that interfacial failure can be mediated by slow slip rupture phenomena which are distinct from ordinary, earthquake-like, fast rupture. These discoveries have influenced the way we think about frictional motion, yet the nature and properties of slow rupture are not completely understood. We show that slow rupture is an intrinsic and robust property of simple non-monotonic rate-and-state friction laws. It is associated with a new velocity scale cmin, determined by the friction law, below which steady state rupture cannot propagate. We further show that rupture can occur in a continuum of states, spanning a wide range of velocities from cmin to elastic wave-speeds, and predict different properties for slow rupture and ordinary fast rupture. Our results are qualitatively consistent with recent high-resolution laboratory experiments and may provide a theoretical framework for understanding slow rupture phenomena along frictional interfaces.

Bar Sinai, Yohai; Brener, Efim A.; Bouchbinder, Eran

2012-02-01

73

The 1 April 2014 Iquique, Chile, Mw 8.1 earthquake rupture sequence  

NASA Astrophysics Data System (ADS)

1 April 2014, a great (Mw 8.1) interplate thrust earthquake ruptured in the northern portion of the 1877 earthquake seismic gap in northern Chile. The sequence commenced on 16 March 2014 with a magnitude 6.7 thrust event, followed by thrust-faulting aftershocks that migrated northward ~40 km over 2 weeks to near the main shock hypocenter. Guided by short-period teleseismic P wave backprojections and inversion of deepwater tsunami wave recordings, a finite-fault inversion of teleseismic P and SH waves using a geometry consistent with long-period seismic waves resolves a spatially compact large-slip (~2-6.7 m) zone located ~30 km downdip and ~30 km along-strike south of the hypocenter, downdip of the foreshock sequence. The main shock seismic moment is 1.7 × 1021 N m with a fault dip of 18°, radiated seismic energy of 4.5-8.4 × 1016 J, and static stress drop of ~2.5 MPa. Most of the 1877 gap remains unbroken and hazardous.

Lay, Thorne; Yue, Han; Brodsky, Emily E.; An, Chao

2014-06-01

74

Earthquake clusters resulting from delayed rupture propagation in finite fault segments  

NASA Astrophysics Data System (ADS)

The question whether the preparation process of foreshocks and main shocks is different from other earthquakes is of great interest with regard to earthquake predictability. We show that the most conspicuous properties of earthquake clustering can be explained without assuming any differences in the initiation processes. In particular, the Gutenberg-Richter law as well as the Omori law for foreshock and aftershock sequences can be reproduced by model simulations with the simple assumption that all subsequent events are initiated in the same manner at the edges of the recently ruptured area. In this way, the empirically observed b and p values are reproduced naturally without any parameter tuning as well as their differences with regard to foreshock and aftershock activity. These properties are shown to result from the shrinking of the loaded fault region with time. In the model, foreshocks occur in extended and almost compact fault segments, whereas aftershocks are mostly restricted to recesses left unruptured by the main shock. Our investigations lead to the conclusion that the spatial effects rather than the temporal effects of the initiation mechanism are decisive for earthquake clustering.

Hainzl, Sebastian; ZöLler, Gert; Scherbaum, Frank

2003-01-01

75

Intrapartum uterine rupture with coincidental uterine adenomyosis in an African wild dog (Lycaon pictus).  

PubMed

A 7-yr-old African wild dog (Lycaon pictus) multiparous bitch experienced severe dystocia and death one day after the onset of parturition. Necropsy revealed three placental attachments in the right uterine horn and one in the left. A full-thickness rupture of the right horn at the middle placental attachment and an autolysed fetus free in the abdomen were present. Death was attributed to hypovolemic and endotoxemic shock after uterine rupture. Myometrium adjacent to the rupture and in the left uterine horn was subdivided into irregular pseudolobules by fibrous connective tissue tracts containing small endometrial glandular acini suggestive of adenomyosis, which may have facilitated uterine rupture. This is the first reported case of dystocia-induced uterine rupture and of adenomyosis in a wild dog. PMID:20063828

Newell-Fugate, Annie; Lane, Emily

2009-12-01

76

Mycotic Aneurysm of the Celiac Trunk: From Early CT Sign to Rupture  

SciTech Connect

We present a case of the rapid development and rupture of a mycotic celiac trunk aneurysm. Initiallyon multislice computed tomography (ms-CT) there was a normal celiac trunk with minimal haziness of the surrounding fat. Only 2 weeks later the patient went into hypovolemic shock due to a ruptured celiac aneurysm. Although aneurysms of the visceral arteries are rare, they are of major clinical importance as they carry a life-threatening risk of rupture. This case illustrates the use of ms-CT in detecting and evaluating visceral aneurysms, in order to prevent emergency operation.

Serafino, Gianpiero, E-mail: serafinog@mcrz.nl; Vroegindeweij, Dammis; Boks, Simone [Medical Centre Rijnmond-Zuid, Department of Radiology (Netherlands); Harst, Erwin van der [Medical Centre Rijnmond-Zuid, Department of Vascular Surgery (Netherlands)

2005-06-15

77

Multi-fluid Dynamics for Supersonic Jet-and-Crossflows and Liquid Plug Rupture  

NASA Astrophysics Data System (ADS)

Multi-fluid dynamics simulations require appropriate numerical treatments based on the main flow characteristics, such as flow speed, turbulence, thermodynamic state, and time and length scales. In this thesis, two distinct problems are investigated: supersonic jet and crossflow interactions; and liquid plug propagation and rupture in an airway. Gaseous non-reactive ethylene jet and air crossflow simulation represents essential physics for fuel injection in SCRAMJET engines. The regime is highly unsteady, involving shocks, turbulent mixing, and large-scale vortical structures. An eddy-viscosity-based multi-scale turbulence model is proposed to resolve turbulent structures consistent with grid resolution and turbulence length scales. Predictions of the time-averaged fuel concentration from the multi-scale model is improved over Reynolds-averaged Navier-Stokes models originally derived from stationary flow. The response to the multi-scale model alone is, however, limited, in cases where the vortical structures are small and scattered thus requiring prohibitively expensive grids in order to resolve the flow field accurately. Statistical information related to turbulent fluctuations is utilized to estimate an effective turbulent Schmidt number, which is shown to be highly varying in space. Accordingly, an adaptive turbulent Schmidt number approach is proposed, by allowing the resolved field to adaptively influence the value of turbulent Schmidt number in the multi-scale turbulence model. The proposed model estimates a time-averaged turbulent Schmidt number adapted to the computed flowfield, instead of the constant value common to the eddy-viscosity-based Navier-Stokes models. This approach is assessed using a grid-refinement study for the normal injection case, and tested with 30 degree injection, showing improved results over the constant turbulent Schmidt model both in mean and variance of fuel concentration predictions. For the incompressible liquid plug propagation and rupture study, numerical simulations are conducted using an Eulerian-Lagrangian approach with a continuous-interface method. A reconstruction scheme is developed to allow topological changes during plug rupture by altering the connectivity information of the interface mesh. Rupture time is shown to be delayed as the initial precursor film thickness increases. During the plug rupture process, a sudden increase of mechanical stresses on the tube wall is recorded, which can cause tissue damage.

Hassan, Ezeldin A.

78

[Surgical consideration of ruptured abdominal aortic aneurysms].  

PubMed

During the recent 18 and a half years, 30 cases of ruptured abdominal aortic aneurysm (including four cases of A-V fistula) were operated at Saiseikai Utsunomiya Hospital. In 26 cases, a conventional graft replacement was performed. In other four cases, axillo-bifemoral bypass (in the cases ruptured into the colon) or other methods were used. Overall operative mortality rate was 26.7%. However, during the last 9 years, operative results were improved (21.7%, 5 deaths out of 23 cases). Amount of intraoperative blood loss influenced the operative results greatly. Other operative risk factors included preoperative shock, preoperative severe cerebrovascular or cardiovascular complications, and postoperative thromboembolism. Factors of recent improvement in mortality included; establishment of emergency system which resulted in earlier operation after the patient's arrival at the hospital, use of occlusive balloon for bleeding control, heparin administration before the aortic clamp for preventing peripheral thromboembolism and introduction of autotransfusion system for reducing the amount of blood transfusion. PMID:2770687

Kiso, I; Yozu, R; Maehara, T; Umezu, Y; Hirotani, T; Ishikura, Y; Takeuchi, S

1989-03-01

79

Uterine rupture: Preventable obstetric tragedies?  

Microsoft Academic Search

Background: Although ruptured uterus is nowadays a rare obstetric emergency in Western countries, it is still alarmingly common in developing countries, where it remains a major cause of maternal mortality and morbidity. Aims: To review the recent experience of uterine rupture at a tertiary obstetric unit in eastern Nepal and to recommend improvements in the current management of labour, especially

Sangeeta K. MISHRA; Norman MORRIS; Dhruba Kumar UPRETY

2006-01-01

80

Spontaneous rupture of the oesophagus  

Microsoft Academic Search

Background: The aim of this study was to evaluate the diagnosis, management and outcome of patients with spontaneous rupture of the oesophagus in a single centre. Methods: Between October 1993 and May 2007, 51 consecutive patients with spontaneous oesophageal rupture were evaluated with contrast radiology and flexible endoscopy. Patients with limited contamination who fulfilled specific criteria were managed by a

S. M. Griffin; P. J. Lamb; J. Shenfine; D. L. Richardson; D. Karat; N. Hayes

2008-01-01

81

Shock capturing  

NASA Technical Reports Server (NTRS)

Recent developments which have improved the understanding of how finite difference methods resolve discontinuous solutions to hyperbolic partial differential equations are discussed. As a result of this understanding improved shock capturing methods are currently being developed and tested. Some of these methods are described and numerical results are presented showing their performance on problems containing shocks in one and two dimensions. A conservative difference scheme is defined. Conservation implies that, except in very special circumstances, shocks must be spread over at least two grid intervals. These two interval shocks are actually attained in one dimension if the shock is steady and an upwind scheme is used. By analyzing this case, the reason for this excellent shock resolution can be determined. This result is used to provide a mechanism for improving the resolution of two dimensional steady shocks. Unfortunately, this same analysis shows that these results cannot be extended to shocks which move relative to the computing grid. Total variation diminishing (TVD) finite difference schemes and flux limiters are introduced to deal with money shocks and contact discontinuities.

Davis, S. F.

1985-01-01

82

Rupture of the uterus: a review of 32 cases in a general hospital in Zambia.  

PubMed

During July 1993 to June 1994, in Zambia, 32 pregnant women aged 15-46 years suffered from uterine rupture at Mansa General Hospital, a referral center for Luapula province. Adolescent women were significantly more likely to have had a uterine rupture than all women delivering (38% vs. 17%; p 0.01). Nulliparity was more common among the uterine rupture cases than among all women giving birth (44% vs. 27%; p 0.05). Multiparity was just as common. 63% of uterine rupture cases had had no prenatal care. In 94% of cases the rupture occurred during labor. Some identified contributing factors for uterine rupture were cephalopelvic disproportion (24 cases), previous cesarean section (3), and oxytocic stimulation and assisted breech delivery with undiagnosed mild hydrocephalus (2). 44% of the women died postoperatively. Sepsis was the leading cause of death (79%). Mortality was associated with nulliparity (79%), adolescence (71%), and anemia, sepsis, and shock on admission (64%). Sepsis and maternal death increased with time since rupture and distance between patient's home or referring center and hospital. Prenatal care did not affect maternal death. All the babies died. These findings emphasize the need for health education of rural residents, training and supervision of traditional birth attendants, and available transportation. In cases of uterine rupture, later marriage, family planning use, and obstetric care may improve maternal prognosis. PMID:8634565

Nkata, M

1996-05-11

83

Spontaneous rupture of adrenal haemangioma mimicking abdominal aortic aneurysm rupture  

PubMed Central

Serious bleeding from a ruptured adrenal mass limits preoperative diagnostics and can necessitate urgent laparotomy to control blood loss. A 45-year old man underwent an emergency laparotomy due to severe retroperitoneal haemorrhage causing hypovolaemia. Detailed retroperitoneal dissection after splenectomy and clamping of the abdominal aorta revealed bleeding from a ruptured haemangioma of the left adrenal gland. Following a left adrenalectomy, the patient returned to a stable haemodynamic state. Adrenal haemangiomas are rare, but may cause spontaneous life-threatening haemorrhage. PMID:22371732

Ambroziak, Iwona; Holynska-Dabrowska, Katarzyna; Siezieniewska-Skowronska, Zofia; Paluszkiewicz, Andrzej

2010-01-01

84

[Diagnosis and treatment of diaphragm traumatic ruptures].  

PubMed

29 patients with traumatic ruptures of left cupola of the diaphragm were studied. Pain, dispnoe, tachycardia more intensive after a meal due to repletion and dislocation of the stomach into pleural cavity and its pressure on the organs of the mediastinum were the main symptoms of the disease. The diagnosis of traumatic rupture of the diaphragm was made on the base of clinical and roentgenological examination. In the acute period of trauma the diagnosis is difficult, especially in combined trauma. In 92.3% of cases the stomach and the bowel move into the pleural cavity, which may simulate pneumothorax or relaxation of the diaphragm. Contrast examination of the gastro-intestinal tract and pleural puncture help in differential diagnosis. All the cases of traumatic ruptures of the diaphragm should be subjected to surgical treatment. Urgent operation is indicated in continuing bleeding, incarceration of organs, acute cardiopulmonary insufficiency due to the collapse of the lung and dislocation of mediastinal organs of into contralateral position. Thoracotomy in VII intercostal space is considered as a valid approach. There were 2 (6.9%) lethal outcomes after 29 operations. Long-term results are quite favourable. PMID:10459187

Gadzhiev, Sh M; Gurbanaliev, I G; Abbasov, F; Mamedov, A S; Ze?nalov, N D; Iusifov, I A

1999-01-01

85

Imaging gate oxide ruptures  

NASA Astrophysics Data System (ADS)

As minimum feature sizes are reduced in MOS silicon devices, dielectric breakdown continues to pose a formidable challenge. A more complete understanding of the failure mechanism which induces oxide rupture has become an absolute necessity in order to meet the advancing yield and reliability requirements of today's complex integrated structures. This paper will present an interesting insight into the nature of dielectric breakdown in MOS transistors produced from a novel cross-sectioning TEM sample preparation method using a focused ion beam tool. By using deductive failure analysis, it was possible to determine the location of the leakage within a 1000 angstroms portion of the transfer gate of a one megabit DRAM. Once localized, a creative combination of conventional glass lapping and focused ion beam techniques were used to produce the thin TEM slice which contained the oxide breakdown. An image of the breakdown was then obtained on a 200 keV TEM. Interestingly, the image revealed that the origin of the breakdown was associated with imperfections in the form of voids in the surface of the silicon substrate. These results proved to be consistent over multiple samples. In this paper a complete description of these images will be presented along with possible theories describing the fundamental origin of these defects.

Mendez, Horacio; Morris, Steve; Tatti, Sudhindra; Dickson, Nicholas; Pyle, Ronald E.

1993-01-01

86

Ruptured Aneurysm of Intercostal Arteriovenous Malformation Associated With Neurofibromatosis Type 1: A Case Report  

SciTech Connect

Intercostal arteriovenous malformations (AVM) are rare, with most being secondary to trauma or iatrogenic therapeutic procedures. Only one case of presumably congenital AVM has been reported. Here we report the first case of a ruptured aneurysm of intercostal AVM associated with neurofibromatosis type 1 in a 32-year-old woman who experienced hypovolemic shock caused by massive hemothorax.

Kim, Hyung Jun; Seon, Hyun Ju, E-mail: sunaura@hanmail.net; Choi, Song; Jang, Nam Kyu [Chonnam National University Hospital, Department of Radiology (Korea, Republic of)

2011-02-15

87

Steam generator tube rupture study  

E-print Network

This report describes our investigation of steam generator behavior during a postulated tube rupture accident. Our study was performed using the steam generator, thermal-hydraulic analysis code THERMIT-UTSG. The purpose ...

Free, Scott Thomas

1986-01-01

88

Partial ACL rupture: an MR diagnosis?  

Microsoft Academic Search

Purpose. We sought to clarify the ability of magnetic resonance imaging (MR) to show partial ante- rior cruciate ligament (ACL) ruptures and to allow dis- tinction of partial from complete ACL ruptures. Materials and methods. Eighty-eight patients were stud- ied by arthroscopy and MR (36 with normal ACLs, 21 with partial ACL ruptures, and 31 with complete ACL ruptures). MR

Lawrence Yao; Amilcare Gentili; Leonard Petrus; Joong K. Lee

1995-01-01

89

Rupture of a Biomembrane under Dynamic Surface Tension  

E-print Network

How long a fluid membrane vesicle stressed with a steady ramp of micropipette last before rupture? Or conversely, how high the surface tension should be to rupture a membrane? To answer these challenging questions we have developed a theoretical framework that allows description and reproduction of Dynamic Tension Spectroscopy (DTS) observations. The kinetics of the membrane rupture under ramps of surface tension is described as a combination of initial pore formation followed by Brownian process of the pore radius crossing the time-dependent energy barrier. We present the formalism and derive (formal) analytical expression of the survival probability describing the fate of the membrane under DTS conditions. Using numerical simulations for the membrane prepared in an initial state with a given distribution of times for pore nucleation, we have studied the membrane lifetime (or inverse of rupture rate) and distribution of membrane surface tension at rupture as a function of membrane characteristics like pore nucleation rate, the energy barrier to failure and tension loading rate. It is found that simulations reproduce main features of the experimental data, particularly, the pore nucleation and pore size diffusion controlled limits of membrane rupture dynamics. This approach can also be applied to processes of permeation and pore opening in membranes (electroporation, membrane disruption by antimicrobial peptides, vesicle fusion).

D. J. Bicout; E. I. Kats

2011-12-19

90

Rupture of a biomembrane under dynamic surface tension  

NASA Astrophysics Data System (ADS)

How long will a fluid membrane vesicle stressed with a steady ramp of micropipette last before rupture? Or conversely, how high should the surface tension be to rupture such a membrane? To answer these challenging questions we developed a theoretical framework that allows for the description and reproduction of dynamic tension spectroscopy (DTS) observations. The kinetics of the membrane rupture under ramps of surface tension is described as a succession of an initial pore formation followed by the Brownian process of the pore radius crossing the time-dependent energy barrier. We present the formalism and a derive (formal) analytical expression of the survival probability describing the fate of the membrane under DTS conditions. Using numerical simulations for the membrane prepared in an initial state with a given distribution of times for pore nucleation, we study the membrane lifetime (or inverse of rupture rate) and distribution of membrane surface tension at rupture as a function of membrane characteristics like pore nucleation rate, the energy barrier to failure, and tension loading rate. It is found that simulations reproduce the main features of DTS experiments, particularly the pore nucleation and pore-size diffusion-controlled limits of membrane rupture dynamics. This approach can be adapted and applied to processes of permeation and pore opening in membranes (electroporation, membrane disruption by antimicrobial peptides, vesicle fusion).

Bicout, D. J.; Kats, E.

2012-03-01

91

A support-operator method for 3-D rupture dynamics  

NASA Astrophysics Data System (ADS)

We present a numerical method to simulate spontaneous shear crack propagation within a heterogeneous, 3-D, viscoelastic medium. Wave motions are computed on a logically rectangular hexahedral mesh, using the generalized finite-difference method of Support Operators (SOM). This approach enables modelling of non-planar surfaces and non-planar fault ruptures. Our implementation, the Support Operator Rupture Dynamics (SORD) code, is highly scalable, enabling large-scale, multiprocessors calculations. The fault surface is modelled by coupled double nodes, where rupture occurs as dictated by the local stress conditions and a frictional failure law. The method successfully performs test problems developed for the Southern California Earthquake Center (SCEC)/U.S. Geological Survey (USGS) dynamic earthquake rupture code validation exercise, showing good agreement with semi-analytical boundary integral method results. We undertake further dynamic rupture tests to quantify numerical errors introduced by shear deformations to the hexahedral mesh. We generate a family of meshes distorted by simple shearing, in the along-strike direction, up to a maximum of 73°. For SCEC/USGS validation problem number 3, grid-induced errors increase with mesh shear angle, with the logarithm of error approximately proportional to angle over the range tested. At 73°, rms misfits are about 10 per cent for peak slip rate, and 0.5 per cent for both rupture time and total slip, indicating that the method (which, up to now, we have applied mainly to near-vertical strike-slip faulting) is also capable of handling geometries appropriate to low-angle surface-rupturing thrust earthquakes. Additionally, we demonstrate non-planar rupture effects, by modifying the test geometry to include, respectively, cylindrical curvature and sharp kinks.

Ely, Geoffrey P.; Day, Steven M.; Minster, Jean-Bernard

2009-06-01

92

Alliance ruptures and rupture resolution in cognitive–behavior therapy: A preliminary task analysis  

Microsoft Academic Search

An initial ideal, rational model of alliance rupture and rupture resolution provided by cognitive–behavioral therapy (CBT) experts was assessed and compared with empirical observations of ruptures and their resolution in two cases of successful CBT. The initial rational model emphasized nondefensive acknowledgment and exploration of the rupture. Results indicated differences between what therapists think they should do to resolve ruptures

Helen Aspland; Susan Llewelyn; Gillian E. Hardy; Michael Barkham; William Stiles

2008-01-01

93

Scientific Challenges in Developing the Next Uniform California Earthquake Rupture Forecast (UCERF3)  

Microsoft Academic Search

The Working Group on California Earthquake Probabilities (WGCEP) is in the process of developing the next-generation Uniform California Earthquake Rupture Forecast (UCERF version 3). The main goals for this future model, which is being developed jointly by the United States Geological Survey, California Geological Survey, and Southern California Earthquake Center, are to include multi-fault ruptures and spatial and temporal clustering.

E. H. Field

2009-01-01

94

Collective osmotic shock in ordered materials  

NASA Astrophysics Data System (ADS)

Osmotic shock in a vesicle or cell is the stress build-up and subsequent rupture of the phospholipid membrane that occurs when a relatively high concentration of salt is unable to cross the membrane and instead an inflow of water alleviates the salt concentration gradient. This is a well-known failure mechanism for cells and vesicles (for example, hypotonic shock) and metal alloys (for example, hydrogen embrittlement). We propose the concept of collective osmotic shock, whereby a coordinated explosive fracture resulting from multiplexing the singular effects of osmotic shock at discrete sites within an ordered material results in regular bicontinuous structures. The concept is demonstrated here using self-assembled block copolymer micelles, yet it is applicable to organized heterogeneous materials where a minority component can be selectively degraded and solvated whilst ensconced in a matrix capable of plastic deformation. We discuss the application of these self-supported, perforated multilayer materials in photonics, nanofiltration and optoelectronics.

Zavala-Rivera, Paul; Channon, Kevin; Nguyen, Vincent; Sivaniah, Easan; Kabra, Dinesh; Friend, Richard H.; Nataraj, S. K.; Al-Muhtaseb, Shaheen A.; Hexemer, Alexander; Calvo, Mauricio E.; Miguez, Hernan

2012-01-01

95

Septic Shock  

Microsoft Academic Search

\\u000a Septic shock is accompanied by profound cardiovascular alterations, including a decrease in vascular tone, hypovolemia, and\\u000a myocardial depression. Hence, the hemodynamic treatment represents a true challenge for intensivists because all of these\\u000a mechanisms of shock can be associated, and at any given moment the dominant mechanism may be different. Making the correct\\u000a diagnosis thus becomes somewhat complicated, especially with adapted

Daniel De Backer; Antoine Vieillard-Baron

96

Are gauge shocks really shocks?  

NASA Astrophysics Data System (ADS)

The existence of gauge pathologies associated with the Bona Masso family of generalized harmonic slicing conditions is proven for the case of simple 1+1 relativity. It is shown that these gauge pathologies are true shocks in the sense that the characteristic lines associated with the propagation of the gauge cross, which implies that the name 'gauge shock' usually given to such pathologies is indeed correct. These gauge shocks are associated with places where the spatial hypersurfaces that determine the foliation of spacetime become non-smooth.

Alcubierre, Miguel

2005-10-01

97

Elbow tendinopathy and tendon ruptures: epicondylitis, biceps and triceps ruptures.  

PubMed

Lateral and medial epicondylitis are common causes of elbow pain in the general population, with the lateral variety being more common than the medial by a ratio reportedly ranging from 4:1 to 7:1. Initially thought to be an inflammatory condition, epicondylitis has ultimately been shown to result from tendinous microtearing followed by an incomplete reparative response. Numerous nonoperative and operative treatment options have been employed in the treatment of epicondylitis, without the emergence of a single, consistent, universally accepted treatment protocol. Tendon ruptures about the elbow are much less frequent, but result in more significant disability and loss of function. Distal biceps tendon ruptures typically occur in middle-aged males as a result of an event that causes a sudden, eccentric contraction of the biceps. Triceps tendon ruptures are exceedingly rare but usually have a similar etiology with a forceful eccentric contraction of the triceps that causes avulsion of the tendon from the olecranon. The diagnosis of these injuries is not always readily made. Complete ruptures of the biceps or triceps tendons have traditionally been treated surgically with good results. With regard to biceps ruptures, there continues to be debate about the best surgical approach, as well as the best method of fixation of tendon to bone. This article is not meant to be an exhaustive review of the broad topics of elbow tendinopathy and tendon ruptures, but rather is a review of recently published information on the topics that will assist the clinician in diagnosis and management of these conditions. PMID:19258160

Rineer, Craig A; Ruch, David S

2009-03-01

98

Cervical ruptures in midtrimester abortions.  

PubMed

2 groups of patients are at risk of traumatic complication after midtrimester abortion: older multiparous women (uterine ruptures) and young primigravid women (cervical ruptures). While the occurrence of uterine ruptures in the former class can be reduced by selective use of abortifacient agents, and avoidance of amnioinfusions and intravenous oxytocin, the occurrence of cervical ruptures continues to be high. From May 1974 through May 1978, 780 women underwent midtrimester abortion by various techniques. 12 patients (1.5%) sustained cervical injuries, 11 of whom were nulliparous aged 16 to 25 years. Intra-amniotic and extra-ovular methods alike produced cervical injuries. The combined method of induction increases the likelihood of damaging the cervix. Oxytocic augmentation, however, does not appear to increase its incidence. Nor does a shorter induction-abortion interval, according to the evidence. Since laminaria tents did not prevent cervical injuries, none of the presently available methods offers any protection. Nevertheless, it may be that cervical injuries can be prevented if midtrimester abortions are undertaken between 13 and 15 weeks of pregnancy. Cervical ruptures can also go unnoticed and cause future obstetric problems; the authors therefore emphasize the importance of routine cervical inspection in all patients. PMID:12335921

Rajan, R; Usha, K R

1979-06-01

99

Compression and rarefaction waves in shock-compressed metals  

Microsoft Academic Search

The behavior of duralumin and copper is studied under conditions of specimen loading by two successive shock waves and during unloading after the shock compression. The amplitude of the first shock wave was 150–250 kbar. Direct measurements were performed of the difference in main stresses behind the shock front in duralumin. The results obtained do not agree with existing concepts

A. N. Dremin; G. I. Kanel

1976-01-01

100

Dynamic Rupture Activation of Backthrust Fault Branching Shiqing Xua  

E-print Network

thrust fault. Simulations with slip- weakening fault friction and homogeneous initial stress show several additional effects. The sign of the triggered motion along the backthrust can be reversed from thrust to normal if a deeply nucleated main rupture breaks the free surface, while it is preserved

Ben-Zion, Yehuda

101

MAINE AQUIFERS  

EPA Science Inventory

AQFRS24 contains polygons of significant aquifers in Maine (glacial deposits that are a significant ground water resource) mapped at a scale 1:24,000. This statewide coverage was derived from aquifer boundaries delineated and digitized by the Maine Geological Survey from data com...

102

Chondrule destruction in nebular shocks  

E-print Network

Chondrules are millimeter-sized silicate spherules ubiquitous in primitive meteorites, but whose origin remains mysterious. One of the main proposed mechanisms for producing them is melting of solids in shock waves in the gaseous protoplanetary disk. However, evidence is mounting that chondrule-forming regions were enriched in solids well above solar abundances. Given the high velocities involved in shock models destructive collisions would be expected between differently sized grains after passage of the shock front as a result of differential drag. We investigate the probability and outcome of collisions of particles behind a 1D shock using analytic methods as well as a full integration of the coupled mass, momentum, energy and radiation equations. Destruction of protochondrules seems unavoidable for solid/gas ratios $\\epsilon \\gtrsim 0.1$, and possibly even for solar abundances because of "sandblasting" by finer dust. A flow with $\\epsilon \\gtrsim 10$ requires much smaller shock velocities ($\\sim 2$ vs 8 k...

Jacquet, Emmanuel

2014-01-01

103

Ruptures of the rotator cuff.  

PubMed Central

Through the use of improved diagnostic techniques, including arthrography and arthroscopy, ruptures of the rotator cuff that previously might not have been recognized are now being identified more frequently. In most cases the symptoms are relatively mild and respond satisfactorily to rest and therapy. Occasionally, however, there is severe, persistent disability despite treatment. These ruptures require surgical repair. In such cases the data obtained from special investigations help the surgeon select the appropriate surgical approach and repair technique. An imaginative program of physiotherapy before and after the operation contributes greatly to a satisfactory result. Images FIG. 3 FIG. 4 FIG. 5 FIG. 6 FIG. 7 PMID:7437980

Ha'eri, G B

1980-01-01

104

[Neurogenic shock].  

PubMed

The neurogenic shock is a common complication of spinal cord injury, especially when localized at the cervical level. Characterized by a vasoplegia (hypotension) and bradycardia, the neurogenic shock is secondary to the damage of the sympathetic nervous system. The clinical presentation often includes tetraplegia, with or without respiratory failure. Early treatment aims to minimize the occurrence of secondary spinal cord lesions resulting from systemic ischemic injuries. Medical management consists in a standardized ABCDE approach, in order to stabilize vital functions and immobilize the spine. The hospital care includes performing imaging, further measures of neuro-resuscitation, and coordinated surgical assessment and treatment of any other injury. PMID:25199226

Meister, Rafael; Pasquier, Mathieu; Clerc, David; Carron, Pierre-Nicolas

2014-08-13

105

Waveform inversion for rupture process using a non-flat seafloor model: Application to 1986 Andreanof Islands and 1985 Chile earthquakes  

NASA Astrophysics Data System (ADS)

Yoshida, S., 1992. Waveform inversion for rupture process using a non-flat seafloor model: application to 1986 Andreanof Islands and 1985 Chile earthquakes. In: T. Mikumo, K. Aki, M. Ohnaka, L.J. Ruff and P.K.P. Spudich (Editors), Earthquake Source Physics and Earthquake Precursors. Tectonophysics, 211: 45-59. We inverted teleseismic P waveforms to infer rupture processes of subduction zone earthquakes using Green's functions computed for realistic seafloor topography because reverberations in the water layer near the source affect the teleseismic waveforms. We modeled the seafloor by a series of several plane surfaces with appropriate dip and performed three-dimensional ray tracing to compute Green's functions. From the GDSN seismograms, spatial and temporal slip distributions were estimated for the 1986 Andreanof Islands earthquake ( Ms 7.7) and the 1985 Chile earthquake ( Ms 7.8). To suppress unstable parts of the least-squares solution, we introduced some stabilizing constraints. The 1986 Andreanof Islands earthquake was analyzed using two kinds of source models: the first one has a prescribed rupture velocity and the second one allows any point to slip at any time. The solutions by the two models gave similar patterns of slip distribution. A relatively small subevent initially occurred and then a dominant subevent with a moment of about five times larger occurred with a center about 80 km west of the hypocenter. For the 1985 Chile earthquake, a small initial subevent was also found and a major rupture with a ten times larger moment extended approximately from 20 to 70 km south of the hypocenter. For both the earthquakes, it was found that most of the one-day aftershocks occurred in areas where a small moment was released during the main shock.

Yoshida, Shingo

1992-09-01

106

Double valve replacement for acute spontaneous left chordal rupture secondary to chronic aortic incompetence.  

PubMed

A 54 years old male with undiagnosed chronic calcific degenerative aortic valve incompetence presented with acute left anterior chordae tendinae rupture resulting in severe left heart failure and cardiogenic shock. He was successfully treated with emergency double valve replacement using mechanical valves. The pathogenesis of acute rupture of the anterior chordae tendinae, without any evidence of infective endocarditis or ischemic heart disease seems to have been attrition of the subvalvular mitral apparatus by the chronic regurgitant jet of aortic incompetence with chronic volume overload. We review the literature with specific focus on the occurrence of this unusual event. PMID:17026749

Agarwala, Sandeep; Kumar, Sanjay; Berridge, John; McLenachan, Jim; O'Regan, David J

2006-01-01

107

Transition of slow shocks to fast shocks  

NASA Technical Reports Server (NTRS)

As a CME pushes its way through preceding slower solar wind, large disturbances in the interaction region may evolve to form transient MHD shocks. The shocks can be slow shocks in the coronal space but they appear as fast shocks near 1 AU. We use a polytropic MHD model to study the transition of slow shocks to fast shocks in an interaction region sandwiched between a faster solar wind and a slower solar wind near the equatorial plane. The polytropic index controls the radial increase of Beta outside the interaction region. The transition process is attributed chiefly to the increase of Beta and theta to a lesser degree to the radial increase of the shock angle 0. Under the initial condition of small Beta and theta near 0.1 AU, the interaction region evolves to form a pair of slow shocks inside 0.15 AU. As the interaction region convects outward. the increases of B and theta cause a transition of the shock system between 0.15 and 0.3 AU from a slow shock pair to a double shock pair consisting of both slow and fast shocks. As the system moves outward, and Beta continue to increase, the fast shock grows stronger, and the slow shock becomes weaker. Eventually. the slow shocks fade away, and the shock system finally evolves to a pair of fast shocks. Parametric studies of the transition process are carried out for shocks formed over a wide range of disturbances.

Whang, Y. C.

1995-01-01

108

Traumatic pericardial rupture with skeletonized phrenic nerve  

Microsoft Academic Search

BACKGROUND: Traumatic pericardial rupture is a rare presentation. Pericardial rupture itself is asymptomatic unless complicated by either hemorrhage or herniation of the heart through the defect. Following diagnosis surgical repair of the pericardium is indicated because cardiac herniation may result in vascular collapse and sudden death. OBJECTIVES: Here we present a case of traumatic, non-herniated pericardial rupture with complete skeletonization

Zain Khalpey; Taufiek K Rajab; Jan D Schmitto; Philipp C Camp

2011-01-01

109

A Retrospective Analysis of Ruptured Breast Implants  

PubMed Central

Background Rupture is an important complication of breast implants. Before cohesive gel silicone implants, rupture rates of both saline and silicone breast implants were over 10%. Through an analysis of ruptured implants, we can determine the various factors related to ruptured implants. Methods We performed a retrospective review of 72 implants that were removed for implant rupture between 2005 and 2014 at a single institution. The following data were collected: type of implants (saline or silicone), duration of implantation, type of implant shell, degree of capsular contracture, associated symptoms, cause of rupture, diagnostic tools, and management. Results Forty-five Saline implants and 27 silicone implants were used. Rupture was diagnosed at a mean of 5.6 and 12 years after insertion of saline and silicone implants, respectively. There was no association between shell type and risk of rupture. Spontaneous was the most common reason for the rupture. Rupture management was implant change (39 case), microfat graft (2 case), removal only (14 case), and follow-up loss (17 case). Conclusions Saline implants have a shorter average duration of rupture, but diagnosis is easier and safer, leading to fewer complications. Previous-generation silicone implants required frequent follow-up observation, and it is recommended that they be changed to a cohesive gel implant before hidden rupture occurs.

Baek, Woo Yeol; Lew, Dae Hyun

2014-01-01

110

Shock Waves  

NSDL National Science Digital Library

This web page explains the physics of sonic shock waves. Text and animations describe and illustrate the wavefronts of sound from a moving point source for the cases of motion equal to, less than, and greater than the speed of sound. This is part of a large collection of physics animations.

2006-06-14

111

MAINE WOODLOTS  

EPA Science Inventory

MEOWN250 describes industrial, non-industrial, and public woodlot ownership in Maine at 1:250,000 scale. Industrial owners are those having at least one primary wood processing facility. Non-industrial owners are those with no primary wood processing facility. Public ownership...

112

Detonation Shock Radius Experiments.  

NASA Astrophysics Data System (ADS)

A previous passover experiment [1] was designed to create a complex detonation transient used in validating a reduced, asymptotically derived description of detonation shock dynamics (DSD). An underlying question remained on determining the location of the initial detonation shock radius to start the DSD simulation with respect to the dynamical response of the initiation system coupling's to the main charge. This paper concentrates on determining the initial shock radius required of such DSD governed problems. `Cut-back' experiments of PBX-9501 were conducted using an initiation system that sought to optimize the transferred detonation to the desired constant radius, hemispherical shape. Streak camera techniques captured the breakout on three of the prism's surfaces for time-of-arrival data. The paper includes comparisons to simulations using constant volume explosion and high pressure hot spots. The results of the experiments and simulation efforts provide fundamental design considerations for actual explosive systems and verify necessary conditions from which the asymptotic theory of DSD may apply. [1] Lambert, D., Stewart, D. Scott and Yoo, S. and Wescott, B., ``Experimental Validation of Detonation Shock Dynamics in Condensed Explosives. J. of Fluid Mechs., Vol. 546, pp.227-253 (2006).

Lambert, David; Debes, Joshua; Stewart, Scott; Yoo, Sunhee

2007-06-01

113

Slip compensation at fault damage zones along earthquake surface ruptures  

NASA Astrophysics Data System (ADS)

Surface ruptures associated with earthquake faulting commonly comprise a number of segments, and the discontinuities form tip and linking damage zones, which are deformed regions consisting of secondary features. Stress transferring or releasing, when seismic waves pass through the discontinuities, could produce different slip features depending on rupture propagation or termination. Thus, slip patterns at fault damage zones can be one of the key factors to understand fault kinematics, fault evolution and, hence, earthquake hazard. In some previous studies (e.g. Peacock and Sanderson, 1991; Kim and Sanderson, 2005), slip distribution along faults to understand the connectivity or maturity of segmented faults system have commonly been analyzed based on only the main slip components (dip-slip or strike-slip). Secondary slip components, however, are sometimes dominant at fault damage zones, such as linkage and tip zones. In this study, therefore, we examine slip changes between both main and secondary slip components along unilaterally propagated coseismic strike-slip ruptures. Horizontal and vertical components of slip and the slip compensation patterns at tip and linking damage zones are various from slip deficit (decrease in both slip components) through slip compensation (increase of vertical slip with horizontal slip decrease) to slip neutral. Front and back tip zones, which are classified depending on main propagation direction of earthquake ruptures, show different slip patterns; slip compensation is observed at the frontal tip whilst slip deficit occurs at the back tip zone. Average values of the two slip components and their compensative patterns at linking damage zones are closely related with the ratio of length to width (L/W) of linkage geometry; the horizontal slip is proportional to the ratio of L/W, whilst the vertical slip shows little dependence on the value L/W. When the L/W is greater than ~2, average values of two slip components are almost similar to those of the main traces. In contrast, when the L/W < 2, the vertical slip is either increased or decreased as the horizontal slip is decreased, depending on the maturity of the linking zone. Thus, we argue that slip patterns at linking damage zones may be controlled by the LW-ratio of linking damage zones and hence structural maturities of the segmented fault systems. In conclusion, slip patterns at fault damage zones along earthquake surface ruptures are various depending on the maturity of linkage zones and/or the rupture propagation direction. Therefore, the consideration of slip compensation as well as damage structures along surface ruptures must be very useful to understand fault evolution and, hence, to assess seismic hazards around active fault systems.

Choi, J.; Kim, Y.

2013-12-01

114

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

115

The 58th Shock and Vibration Symposium, volume 1  

NASA Technical Reports Server (NTRS)

The proceedings of the 58th Shock and Vibration Symposium, held in Huntsville, Alabama, October 13 to 15, 1987 are given. Mechanical shock, dynamic analysis, space shuttle main engine vibration, isolation and damping, and analytical methods are discussed.

Pilkey, Walter D. (compiler); Pilkey, Barbara F. (compiler)

1987-01-01

116

Traumatically ruptured globes in children.  

PubMed

This retrospective study was designed to document the etiology of traumatically ruptured globes in children and to determine the prognostic value of several clinical parameters with respect to visual outcome. Forty-six children 16 years of age and under seen in the emergency room over a 2-year period were found to have full thickness penetration of the globe. Fifty-nine percent of injuries occurred during recreational activities, and 59% occurred outside of the home. Boys outnumbered girls by a 6:1 ratio. For children, initial visual acuity proved to be less valuable as a prognostic indicator with regard to final vision than has been reported in adults. Smaller corneal wounds offered better visual outcomes. Four eyes were enucleated. Ten ruptures (22%) were related to activity involving guns. Four of six BB gun injuries were the result of a ricocheted BB. Visual outcomes in gun-related injuries were particularly poor. PMID:7837018

Rudd, J C; Jaeger, E A; Freitag, S K; Jeffers, J B

1994-01-01

117

Compound earthquakes on a bimaterial interface and implications for rupture mechanics  

NASA Astrophysics Data System (ADS)

Earthquake ruptures on the San Andreas Fault are affected by the material contrast across the fault. Previous observations of microearthquakes at the northern end of the creeping section have found strong signals of asymmetry in both rupture directivity (preferential propagation to the SE), and aftershock asymmetry (many more to the NW, on timescales from 10 s to 9 hr). To understand the aftershock asymmetry, Rubin & Ampuero simulated slip-weakening ruptures on a bimaterial interface and observed differences in the timescales for the two edges to experience their peak stress after being slowed by barriers. This is suggestive of the possibility of asymmetry of subevents in compound earthquakes. A second possible source of subevent asymmetry is that when slowed by barriers, a significant tensile stress pulse is predicted to propagate in the SE but not the NW direction. To study the possible asymmetry of subevent distribution, we search for compound events using an empirical Green's function method. Three sections on the northern San Andreas and part of the Calaveras faults were selected where the events have high spatial density and similar focal mechanisms. About 677 candidate compound events were identified in a 28 869-event catalogue from 1984 to 2009. Most delays between the two subevents cluster around the shear wave transit time over the subevent separation, although with considerable scatter. For subevents on the San Andreas Fault separated by 0.7-2 times the estimated radius of the first subevent (the same spatial separation found to exhibit strong asymmetry of longer term aftershocks), nearly twice as many second subevents occurred to the SE of the first than to the NW. This asymmetry of second subevent distribution is not present on the Calaveras Fault, which does not have a significant across-fault contrast in wave speed in this region. One interpretation is that the extra SE subevents on the San Andreas Fault are representative of the events `missing'from the `longer term'(10 s-9 hr) aftershock population because they became part of the main shock.

Wang, Enning; Rubin, Allan M.; Ampuero, Jean-Paul

2014-05-01

118

Spontaneous splenic rupture following the administration of intravenous heparin: case report and retrospective case review.  

PubMed

We report the case of a 40-year-old African-American female who presented to the Emergency Department with unstable angina. The patient, who had multiple risk factors for coronary artery disease, was admitted to the coronary care unit for cardiac work-up and management. Shortly after the intravenous administration of unfractionated heparin, she suffered the acute onset of upper abdominal pain and shock. A CT scan of the abdomen revealed splenic rupture with hemoperitoneum. The patient, who was managed surgically, had complete recovery before discharge. A review of systems and medical records revealed no obvious risk factors or other potential etiology for this rupture. We herein provide the characteristics of this rarely documented causal relationship between heparin and spontaneous splenic rupture and retrospectively review similar cases in the literature. PMID:12447963

Ghobrial, Michel W; Karim, Mohammad; Mannam, Sunitha

2002-12-01

119

Depiction of ruptured sinus of Valsalva aneurysms by cardiac computed tomography angiography  

PubMed Central

Ruptured sinus of Valsalva aneurysm is an uncommon condition with variable manifestation that results in aortocardiac shunt. The presentation may range from an asymptomatic murmur to cardiogenic shock. The initial diagnosis is established or suspected by two-dimensional echocardiography and colour flow Doppler. Transesophageal echocardiography is especially helpful in delineating the anatomy of the aneurysm and its connections to other chambers. The gold standard diagnostic method for ruptured sinus of Valsalva aneurysm is cardiac catheterization and aortography. Recent reports have suggested a potential role of cardiac computed tomography in establishing diagnosis in such cases. The high spatial resolution of cardiac computed tomography provides anatomical details of the ruptured aneurysm by depicting a jet of contrast materials extending from the aneurysm and adjacent cardiac chamber. In addition, cardiac computed tomography provides a comprehensive cardiac evaluation including coronary artery anatomy, and the presence of other associated cardiac or vascular anomalies. PMID:23620709

Fathala, Ahmed

2012-01-01

120

Depiction of ruptured sinus of Valsalva aneurysms by cardiac computed tomography angiography.  

PubMed

Ruptured sinus of Valsalva aneurysm is an uncommon condition with variable manifestation that results in aortocardiac shunt. The presentation may range from an asymptomatic murmur to cardiogenic shock. The initial diagnosis is established or suspected by two-dimensional echocardiography and colour flow Doppler. Transesophageal echocardiography is especially helpful in delineating the anatomy of the aneurysm and its connections to other chambers. The gold standard diagnostic method for ruptured sinus of Valsalva aneurysm is cardiac catheterization and aortography. Recent reports have suggested a potential role of cardiac computed tomography in establishing diagnosis in such cases. The high spatial resolution of cardiac computed tomography provides anatomical details of the ruptured aneurysm by depicting a jet of contrast materials extending from the aneurysm and adjacent cardiac chamber. In addition, cardiac computed tomography provides a comprehensive cardiac evaluation including coronary artery anatomy, and the presence of other associated cardiac or vascular anomalies. PMID:23620709

Fathala, Ahmed

2012-09-01

121

Percutaneous Treatment of Sac Rupture in Abdominal Aortic Aneurysms Previously Excluded with Endovascular Repair (EVAR)  

Microsoft Academic Search

The purpose of this study was to assess the feasibility and effectiveness of percutaneous endovascular repair of ruptured\\u000a abdominal aortic aneurysms (AAAs) previously treated by EVAR. In the last year, two male patients with AAAs, treated 8 and\\u000a 23 months ago with bifurcated stent-graft, were observed because of lumbar pain and hemorragic shock. Multidetector computed\\u000a tomography (MDCT) showed a retroperitoneal hematoma;

Domenico Laganà; Monica Mangini; Federico Fontana; Paolo Nicotera; Gianpaolo Carrafiello; Carlo Fugazzola

2009-01-01

122

Plane Shock Generator Explosive Lens: PH 13-8 Mo stainless steel versus 4340 steel shock wave separators and LX13 versus PBX9501 explosive particle velocity-time profiles  

Microsoft Academic Search

Sandia National Laboratories is currently involved in the optimization of a Plane Shock Generator Explosive Lens (PSGEL). This PSGEL component is designed to generate a planar shock wave transmitted to perform a function through a steel bulkhead without rupturing or destroying the integrity of the bulkhead. The PSGEL component consists of a detonator, explosive, brass cone and tamper housing. The

Vigil

1993-01-01

123

[Rupture of the diaphragm of late manifestation].  

PubMed

Twenty one cases of delayed diagnosis of ruptured diaphragm caused by closed trauma are reported: 14 on the left side and 7 on the right side. The clinical signs and the modes of presentation are non-specific. Although the history of thoraco-abdominal trauma and the chest x-ray are sufficient to establish the diagnosis of rupture of the left hemidiaphragm, they can only suggest the diagnosis in cases of righ-sided rupture. The mechanism of rupture is more often due to sudden reflex contraction of the diaphragm against a closed glottis than to excessive abdominal pressure caused by the trauma. Diaphragmatic rupture due to closed trauma causes large tears exposing the patient to a low risk of strangulation of intestinal structures in contrast with ruptures due to a penetrating injury, which causes small tears. The diaphragmatic domes must be systematically explored during laparotomy or thoracotomy performed for thoraco-abdominal trauma. PMID:2189337

Lenot, B; Bellenot, F; Regnard, J F; Dartevelle, P; Rojas-Miranda, A; Levasseur, P

1990-01-01

124

Delayed aortic rupture following perforating trauma  

PubMed Central

The immediate death rate for aortic rupture caused by pointed and sharp-edged instruments is very high; however, delayed aortic rupture following the trauma is rarely reported. A patient who had an upper abdominal stab wound was sent to our hospital, and an emergency exploratory laparotomy was performed. No traumatic aortic rupture was found at that time. However, on the fifth day after surgery, aortic rupture occurred, and a large retroperitoneal hematoma was formed. The patient eventually died. Aortic rupture was confirmed by a second emergency exploratory laparotomy and the autopsy. The information from exploratory laparotomies, post-operative observations and treatments, medical imaging reports, and reasons for delayed aortic rupture, as well as the underlying pathophysiological processes, are discussed in this case report.

Yang, Xuefei; Xia, Ligang

2014-01-01

125

Multiple Shocks  

E-print Network

Using gauge/gravity duality, we explore a class of states of two CFTs with a large degree of entanglement, but with very weak local two-sided correlation. These states are constructed by perturbing the thermofield double state with thermal-scale operators that are local at different times. Acting on the dual black hole geometry, these perturbations create an intersecting network of shock waves, supporting a very long wormhole. Chaotic CFT dynamics and the associated fast scrambling time play an essential role in determining the qualitative features of the resulting geometries.

Stephen H. Shenker; Douglas Stanford

2013-12-11

126

Investigation of cryogenic rupture disc design  

NASA Technical Reports Server (NTRS)

Rupture disc designs of both the active (command actuated) and passive (pressure ruptured) types were evaluated for performance characteristics at cryogenic temperatures and for capability to operate in a variety of cryogens, including gaseous and liquid fluorine. The test results, coupled with information from literature and industry searches, were used to establish a statement of design criteria and recommended practices for application of rupture discs to cryogenic rocket propellant feed and vent systems.

Keough, J. B.; Oldland, A. H.

1973-01-01

127

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

128

Spontaneous rupture of uterine leiomyoma during labour.  

PubMed

Uterine rupture in labour requires an emergency caesarean section. In women with a uterine scar, either from gynaecological surgery or from a previous caesarean section, it is well documented that the risk of rupture is higher than in those without. Spontaneous uterine rupture in a uterus with fibroids during pregnancy or labour is extremely rare. We present a case of a 33-year-old, unbooked pregnant woman from Nigeria who had a uterine rupture secondary to fibroids. She required an emergency caesarean section in labour. The fibroids were not removed. Her baby was born alive and in good condition and she made an uneventful recovery. PMID:25199188

Ramskill, Nikki; Hameed, Aisha; Beebeejaun, Yusuf

2014-01-01

129

Broadband Rupture Process of the 2001 Kunlun Fault (Mw 7.8) Earthquake  

NASA Astrophysics Data System (ADS)

We model the source process of the 14 November, 2001 Kunlun fault earthquake using broadband body waves from the Global Digital Seismographic Network (P, SH) and both point-source and distributed slip techniques. The point-source mechanism technique is a non-linear iterative inversion that solves for focal mechanism, moment rate function, depth, and rupture directivity. The P waves reveal a complex rupture process for the first 30 s, with smooth unilateral rupture toward the east along the Kunlun fault accounting for the remainder of the 120 s long rupture. The obtained focal mechanism for the main portion of the rupture is (strike=96o, dip=83o, rake=-8o) which is consistent with both the Harvard CMT solution and observations of the surface rupture. The seismic moment is 5.29×1020 Nm and the average rupture velocity is ˜3.5 km/s. However, the initial portion of the P waves cannot be fit at all with this mechanism. A strong pulse visible in the first 20 s can only be matched with an oblique-slip subevent (MW ˜ 6.8-7.0) involving a substantial normal faulting component, but the nodal planes of this mechanism are not well constrained. The first-motion polarities of the P waves clearly require a strike mechanism with a similar orientation as the Kunlun fault. Field observations of the surface rupture (Xu et al., SRL, 73, No. 6) reveal a small 26 km-long strike-slip rupture at the far western end (90.5o E) with a 45-km long gap and extensional step-over between this rupture and the main Kunlun fault rupture. We hypothesize that the initial fault break occurred on this segment, with release of the normal faulting energy as a continuous rupture through the extensional step, enabling transfer of the slip to the main Kunlun fault. This process is similar to that which occurred during the 2002 Denali fault (MW 7.9) earthquake sequence except that 11 days elapsed between the October 23 (M_W 6.7) foreshock and the initial break of the Denali earthquake along a thrust fault.

Antolik, M.; Abercrombie, R.; Ekstrom, G.

2003-04-01

130

Observation and control of shock waves in individual nanoplasmas.  

PubMed

Using an apparatus that images the momentum distribution of individual, isolated 100-nm-scale plasmas, we make the first experimental observation of shock waves in nanoplasmas. We demonstrate that the introduction of a heating pulse prior to the main laser pulse increases the intensity of the shock wave, producing a strong burst of quasimonoenergetic ions with an energy spread of less than 15%. Numerical hydrodynamic calculations confirm the appearance of accelerating shock waves and provide a mechanism for the generation and control of these shock waves. This observation of distinct shock waves in dense plasmas enables the control, study, and exploitation of nanoscale shock phenomena with tabletop-scale lasers. PMID:24702383

Hickstein, Daniel D; Dollar, Franklin; Gaffney, Jim A; Foord, Mark E; Petrov, George M; Palm, Brett B; Keister, K Ellen; Ellis, Jennifer L; Ding, Chengyuan; Libby, Stephen B; Jimenez, Jose L; Kapteyn, Henry C; Murnane, Margaret M; Xiong, Wei

2014-03-21

131

Magnetic field overshoots in the Venus blow shock  

SciTech Connect

An examination of Pioneer Venus Orbiter fluxgate magnetometer data has shown that magnetic field overshoots occur not only behind quasi-perpendicular bow shocks but also behind quasi-parallel shocks. Overshoots are assocciated only with supercritical shocks. Their amplitudes increase with increasing fast Mach number. Solar wind beta has a lesser effect. The thickness of the overshoot increases with decreasing Theta-BN. The thickness of apparent overshoots detected behind 4 strong fast interplanetary shocks (M greater than M/crit) is about 3 orders of magnitude larger. Multiple crossings of the Venus bow shock were observed mainly at turbulent shocks. Their occurence is not influenced by Theta-BN. 15 references.

Tatrallyay, M.; Luhmann, J.G.; Russell, C.T.

1984-01-01

132

The Diffusive Shock Acceleration Myth  

NASA Astrophysics Data System (ADS)

It is generally accepted that diffusive shock acceleration (DSA) is the dominant mechanism for particle acceleration at shocks. This is despite the overwhelming observational evidence that is contrary to predictions of DSA models. For example, our most recent survey of hourly-averaged, spin-averaged proton distribution functions around 61 locally observed shocks in 2001 at 1 AU found that in 21 cases no particles were accelerated. Spectral indices (? ) of suprathermal tails on the velocity distributions around the 40 shocks that did accelerate particles, showed none of the DSA-predicted correlations of ? with the shock compression ratio and the shock normal to magnetic field angle. Here we will present ACE/SWICS observations of three sets of 72 consecutive one-hour averaged velocity distributions (in each of 8 SWICS spin sectors). Each set includes passage of one or more shocks or strong compression regions. All spectra were properly transformed to the solar wind frame using the detailed, updated SWICS forward model, taking into account the hourly-averaged directions of the solar wind flow, the magnetic field and the ACE spin axis (http://www.srl.caltech.edu/ACE/ASC/). The suprathermal tails are observed to be a combination of locally accelerated and remote tails. The local tails are power laws. The remote tails are also power laws with rollovers at higher energies. When local tails are weak (as is the case especially upstream of strong shocks or compression regions) the remote tails also have a rollover at low energies due to modulation (transport effects). Among our main findings are that (1) the spectral indices of both the local and remote tails are -5 within the uncertainties of the measurements, as predicted by our pump acceleration mechanism, and (2) the velocity distributions are anisotropic with the perpendicular (to the magnetic field) pressure greater than the parallel pressure.

Gloeckler, G.; Fisk, L. A.

2012-12-01

133

MDCT diagnosis of ruptured tubal pregnancy with massive hemoperitoneum.  

PubMed

We report a case of ruptured tubal pregnancy with massive life-threatening hemoperitoneum. The 38 year-old woman presented with gynaecologic haemorrhage, pelvic pain and hypovolemic shock. Without any ambiguity, the diagnosis was directly made during contrast enhanced Multidetector Computed Tomography (MDCT). Massive hemoperitoneum with fresh blood clots in the hypogastric area, active free peritoneal extravasation of intravascular contrast material and dramatic peripheral enhancement, - "ring of fire" sign - of an adnexal cystic structure were the key signs. These signs must be known by the emergency radiologist because of the more and more use of CT as the first imaging modality in emergency departments particularly for patients with abdominal pain and presenting life-threatening symptoms. PMID:17851702

Coulier, Bruno; Malbecq, Stéphane; Brinon, Pierre-Etienne; Ramboux, Adrien

2008-05-01

134

A piston-actuated shock-tube, with laser-Schlieren diagnostics  

NASA Technical Reports Server (NTRS)

The essential construction features of a piston actuated shock tube are described, and its advantages relative to the conventional use of diaphragm ruptures for shock initiation are listed. Typical operational parameters are presented to illustrate the levels of reproducibility achieved. Tests with He and N2 drivers into about 99 percent Ar covered shock speeds from 1.539 +/- 0.002-0.8143 +/- 0.002 mm/microsec, corresponding to 2390-847 K incident shock temperatures. Application of this tube for recording postshock front density gradients of the endoergic dissociation of ethane and the exoergic condensation of iron atoms via the laser-Schlieren technique is described.

Hurst, S. M.; Bauer, S. H.

1993-01-01

135

Chemicophysical processes in shock waves  

Microsoft Academic Search

This article describes the application of shock waves to the study of various processes of chemico-physical interest during the past five to ten years. It is mainly concerned with those processes of atomic and molecular physics which derive from the thermal transfer of energy in the temperature range 1000 to 10 000 °K. These include the following: the excitation of

I R Hurle

1967-01-01

136

Ruptured liver abscess in a neonate.  

PubMed

We report a rare case of 17-day-old neonate, diagnosed to have ruptured liver abscess secondary to Methicillin-resistant Staphylococcal aureus infection. The child presented with septicemia and abdominal distension. On exploration, there was pyoperitoneum with ruptured liver abscess. PMID:22382113

Jain, Prashant; Mishra, Ashwani; Agarawal, Vyom

2012-01-01

137

Dynamic Interface Rupture in Extremely Heterogeneous Media  

Microsoft Academic Search

Fracture experiments of monolithic brittle materials usually show the maximum speed of smooth rupture at some 30 % of the relevant shear wave speed. This experimental maximum rupture speed is by far lower than those predicted by theories and inferred from inversions of seismograms, and some seismic inversions (e.g., the 1979 Imperial Valley, 1992 Landers, 1999 Izmit, 2001 the central

K. Uenishi; K. Tsuji

2007-01-01

138

Longitudinal ruptures of polyester knitted vascular prostheses  

Microsoft Academic Search

Aim: The purpose of the study was the characterization of a type of rupture occurring on warp-knitted polyester vascular prostheses. Materials and Methods: We studied 20 cases of warp-knitted polyester vascular prostheses that were explanted from humans that showed a longitudinal rupture as a part of a collaborative retrieval program. All the prostheses were immediately fixed in a 10% formaldehyde

Nabil Chakfe; Gunnar Riepe; Florence Dieval; Jean-Francois Le Magnen; Lu Wang; Elisabeth Urban; Marc Beaufigeau; Bernard Durand; Herbert Imig; Jean-Georges Kretz

2001-01-01

139

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

140

Isolated rupture of the superficial vein of the penis.  

PubMed

Penile emergencies are rare but when they do occur, prompt diagnosis and treatment are warranted. Emergent conditions of the male genitalia are mainly traumatic, vascular or infectious. Penile emergencies are usually caused by trauma to the penis, during sexual intercourse or manipulation of an erect penis during masturbation. One of the traumatic vascular penile emergencies is superficial penile dorsal vein rupture. This is a rare condition, with just a few reported cases. It is usually taken into differential diagnosis with the other acute penile injuries that present, such as acute penile edema or ecchymosis. We report a case of 59-year-old male with a superficial penile dorsal vein rupture which occurred during manipulation of the erect penis. PMID:24940469

Eken, Alper; Acil, Meltem; Arpaci, Taner

2014-05-01

141

Isolated rupture of the superficial vein of the penis  

PubMed Central

Penile emergencies are rare but when they do occur, prompt diagnosis and treatment are warranted. Emergent conditions of the male genitalia are mainly traumatic, vascular or infectious. Penile emergencies are usually caused by trauma to the penis, during sexual intercourse or manipulation of an erect penis during masturbation. One of the traumatic vascular penile emergencies is superficial penile dorsal vein rupture. This is a rare condition, with just a few reported cases. It is usually taken into differential diagnosis with the other acute penile injuries that present, such as acute penile edema or ecchymosis. We report a case of 59-year-old male with a superficial penile dorsal vein rupture which occurred during manipulation of the erect penis. PMID:24940469

Eken, Alper; Acil, Meltem; Arpaci, Taner

2014-01-01

142

Pore Formation in a Lipid Bilayer under a Tension Ramp: Modeling the Distribution of Rupture Tensions  

PubMed Central

The rupture of fluid membrane vesicles with a steady ramp of micropipette suction has been shown to produce a distribution of breakage tensions, with a mean that rises rapidly with tension rate. Starting from a lattice model that incorporates the essential features of the lipid bilayers held together with hydrophobic forces, and developing it to handle varying tension rates, we reproduce the main features of the experimental results. In essence, we show that the rupture kinetics are driven by the nucleation and growth of pores, with two limiting kinetics—growth-limited and nucleation-limited. The model has been extended to address the role of peptides in solution that can adsorb and insert themselves into the bilayer. At concentrations below those required to spontaneously rupture the membrane, the effect of the peptides is to lower the rupture tensions systematically for all tension rates. PMID:17400693

Boucher, Pierre-Alexandre; Joos, Bela; Zuckermann, Martin J.; Fournier, Luc

2007-01-01

143

Violent Reactions from Non-Shock Stimuli  

NASA Astrophysics Data System (ADS)

Most reactions are thermally initiated, whether from direct heating or dissipation of energy from mechanical, shock, or electrical stimuli. For other than prompt shock initiation, the reaction must spread through porosity or over large surface area to become more violent than just rupturing any confinement. While burning rates are important, high-strain mechanical properties are nearly so, either by reducing existing porosity or generating additional surface area through fracture. In studies of deflagration-to-detonation transition (DDT), it has been shown that reaction violence is reduced if the binder is softened, either by raising the initial temperature or adding a solvent. In studies of cavity collapse in explosives, those with soft rubber binders will deform and undergo mild reaction whereas those with stiff binders will fracture and generate additional surface area for a violent event.

Sandusky, H. W.; Granholm, R. H.

2007-12-01

144

Shock wave measurements  

SciTech Connect

Much of our knowledge of the properties of matter at high pressures, from the static ruby pressure scale to shock compression at Gbar pressures, rests ultimately on the use of shock waves. Simple conservation relations define the initial and final states, leading to absolute measurements. I will describe some methods for measuring the equation of state of materials under shock loading for a variety of methods of shock production, and also describe the basis for other optical methods used widely in shock physics.

Holmes, N.C.

1995-09-12

145

STS-93 SSME Nozzle Tube Rupture Investigation  

NASA Technical Reports Server (NTRS)

STS-93 was launched on July 23, 1999. There was an anomaly at the end of the launch in that the main engines shut down 0.16 second early because sensors detected a low level of oxidizer in the LOX tank (actually the duct from the tank to the vehicle). This resulted in a cutoff velocity for the vehicle that was 16 ft/sec low. It should have been 25872 ft/sec. The OMS engines were subsequently used to achieve the proper orbit. An investigation was immediately initiated into the cause of this LOX tank low level cutoff. It was noticed during the launch that the turbine temperatures for Main Engine 3 (E2019) were approximately 100 F higher than the preflight prediction. Linear Engine Model matching of the data indicated that a nozzle leak best fit the data. Post launch review of the data showed, that at approximately five seconds into the start, numerous parameters indicated small anomalous shifts. These shifts were all consistent with a rupture of nozzle tubes. Post launch review of the films showed that just after Space Shuttle Main Engine (SSME) ignition and just prior to liftoff a streak is seen in the exhaust plume of E2019. Just after liftoff the streak can be seen emanating from the nozzle wall. This photo confirmed that a leak was coming from the nozzle tubes. Based on the photo, the axial location of the leak was estimated to be 28 in. from the aft end of the nozzle and in line with nozzle coolant feed line #1. The streak continued to be visible during the launch.

Romine, W. Dennis

1999-01-01

146

Age at intracranial aneurysm rupture among generations  

PubMed Central

Background: Previous studies have reported intracranial aneurysm (IA) occurring at young ages in subsequent generations. These studies did not correct for duration of follow-up. Second-generation members who would have their ruptured IA late in life may not be detected due to shorter follow-up time than the first generation. We examined families in which ruptured IA occurred in two consecutive generations for the hypothesis that the second generation (F1) was more likely to have a rupture at a younger age than the older generation (F0). Methods: The Familial Intracranial Aneurysm (FIA) Study is a multicenter, international study recruiting families of ruptured and unruptured IA. All available family members are interviewed. Cox proportional hazards regression models and Kaplan-Meier curves were used to examine differences by generation. Results: Although we found that the F1 generation was more likely to have an aneurysm rupture at a younger age than the F0 generation, we found that this was largely because of a lack of follow-up time in the F1 generation. The F1 generation had 50% the rupture rate of the prior generation. When analyzed by Kaplan-Meier curves, we found a tendency to have a slightly later rupture rate in the F1 generation once time to follow-up was included in the analysis model. Conclusions: Families of ruptured intracranial aneurysm (IA) do not appear to demonstrate “anticipation.” Our finding suggests that genetic epidemiology of ruptured IA should examine all types of variations such as single base-pair changes, deletions, insertions, and other variations that do not demonstrate anticipation. GLOSSARY FIA = familial intracranial aneurysm; IA = intracranial aneurysm; SAH = subarachnoid hemorrhage. PMID:19237697

Woo, D; Hornung, R; Sauerbeck, L; Brown, R; Meissner, I; Huston, J; Foroud, T; Broderick, J

2009-01-01

147

Risk factor analysis of perioperative mortality after ruptured bleeding in hepatocellular carcinoma  

PubMed Central

AIM: To discuss strategies and prognosis for the emergency treatment of ruptured bleeding in primary hepatocellular carcinoma. METHODS: The retrospective analysis was performed by examining the emergency treatment experiences of 60 cases of ruptured bleeding in primary hepatocellular carcinoma. The treatment methods included surgical tumour resection, transcatheter arterial embolization (TAE) and non-surgical treatment. Univariate and multivariate analyses were performed to identify the risk factors that impacted 30-d mortality in the research groups. RESULTS: The 30-d mortality of all patients was 28.3% (n = 17). The univariate analysis showed that Child-Pugh C level liver function, shock, massive blood transfusion and large tumour volume were risk factors that influenced 30-d mortality. The multivariate analysis showed that shock and massive blood transfusion were independent risk factors that impacted the 30-d mortality of surgical resection. As for the TAE patients, larger tumour volume was a risk factor towards prognosis. CONCLUSION: Radical resection and TAE therapy would achieve better results in carefully selected ruptured hepatocellular tumours.

Lin, Hao-Ming; Lei, Li-Ming; Zhu, Jie; Li, Guo-Lin; Min, Jun

2014-01-01

148

The Shock Chemistry of Phosphorus in the Shocked Region L1157 B1  

NASA Astrophysics Data System (ADS)

We study the evolution of phosphorous-bearing species in one-dimensional C-shock models. We find that the abundances of P-bearing species depend sensitively on the elemental abundance of P in the gas phase and on the abundance of N atoms in the pre-shock gas. The observed abundance of PN and the non-detection of PO towards L1157 B1 are reproduced in C-shock models with shock velocity v = 20 km s-1 and pre-shock density n(H2) = 104 cm-3 - 105 cm-3, if the elemental abundance of P in the gas phase is ˜ 10-9 relative to hydrogen and the N-atom abundance is n(N)/nH ˜ 10-5 in the pre-shock gas. We also find that P-chemistry is sensitive to O- and N-chemistry, because N atoms are destroyed mainly by OH and NO.

Aota, T.; Aikawa, Y.

2013-10-01

149

Shock-initiation chemistry of nitroarenes  

SciTech Connect

We present evidence that the shock-initiation chemistry of nitroarenes is dominated by the intermolecular hydrogen transfer mechanism discussed previously. The acceleration by pressure, kinetic isotope effect, and product distribution are consistent with the bimolecular transition state rather than rate-determining C-N homolysis. GC-MS analysis of samples which were subjected to a shock wave generated by detonation of nitromethane shows that nitrobenzene produces aniline and biphenyl, and {ital o}-nitrotoluene forms aniline, toluene, {ital o}-toluidine and {ital o}-cresol, but not anthranil, benzoxazinone, or cyanocyclopentadiene. In isotopic labeling experiments {ital o}-nitrotoluene and TNT show extensive H-D exchange on their methyl groups, and C-N bond rupture is not consistent with the formation of aniline from nitrobenzene or nitrotoluene, nor the formation of {ital o}-toluidine from {ital o}-nitrotoluene. Recent work incorporating fast TOF mass spectroscopy of samples shocked and quenched by adiabatic expansion indicates that the initial chemical reactions in shocked solid nitroaromatic explosives proceed along this path. {copyright} {ital 1998 American Institute of Physics.}

Davis, L.L. [DX-1, Mail Stop P-952, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Brower, K.R. [Department of Chemistry, New Mexico Institute of Mining and Technology, Socorro, New Mexico 87801 (United States)

1998-07-01

150

Shock-initiation chemistry of nitroarenes  

SciTech Connect

The authors present evidence that the shock-initiation chemistry of nitroarenes is dominated by the intermolecular hydrogen transfer mechanism discussed previously. The acceleration by pressure, kinetic isotope effect, and product distribution are consistent with the bimolecular transition state kinetic isotope effect, and product distribution are consistent with the bimolecular transition state rather than rate-determining C-N homolysis.GC-MS analysis of samples which were subjected to a shock wave generated by detonation of nitromethane shows that nitrobenzene produces aniline and biphenyl, and o-nitrotoluene forms aniline, toluene, o-toluidine and o-cresol, but not anthranil, benzoxazinone, or cyanocyclopentandiene. In isotopic labeling experiments o-nitrotoluene and TNT show extensive H-D exchange on their methyl groups, and C-N bond rupture is not consistent with the formation of aniline from nitrobenzene or nitrotoluene, nor the formation of o-toluidine from o-nitrotoluene. Recent work incorporating fast TOF mass spectroscopy of samples shocked and quenched by adiabatic expansion shows that the initial chemical reactions in shocked solid nitroaromatic explosives proceed along this path.

Davis, L.L. [Los Alamos National Lab., NM (United States); Brower, K.R. [New Mexico Inst. of Mining and Technology, Socorro, NM (United States). Dept. of Chemistry

1997-11-01

151

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.

2014-08-01

152

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

153

Rupture of lenticulostriate artery aneurysms.  

PubMed

The authors report on 3 rare cases of ruptured lenticulostriate artery (LSA) aneurysms that were heralded by deep cerebral hematomas. The hematomas were unilateral in 2 cases and bilateral in 1; in the bilateral case, only a single LSA aneurysm could be identified on the right side of the brain. Because of their small size (? 2 mm), fusiform aspect, and deep location within the brain, all of the aneurysms were treated conservatively. There was no hemorrhage recurrence, and follow-up angiography demonstrated spontaneous thrombosis in 2 of the 3 cases. The clinical course was favorable in 2 of the 3 patients. The course in the patient with the bilateral hematoma was marked by an ischemic event after the initial episode, resulting in an aggravation of deficits. The cause of this second event was uncertain. Because our knowledge about the natural history of LSA aneurysms is incomplete, there is no consensus concerning a therapeutic strategy. The authors' experience in 3 reported cases leads them to think that a conservative approach involving close angiographic monitoring may be proposed as first-line treatment. If the monitored aneurysm then persists or grows in size, its occlusion should be considered. Nonetheless, other studies are needed to further strengthen the legitimacy of this strategy. PMID:24053505

Heck, Olivier; Anxionnat, René; Lacour, Jean-Christophe; Derelle, Anne-Laure; Ducrocq, Xavier; Richard, Sébastien; Bracard, Serge

2014-02-01

154

Spontaneous common iliac arteries rupture in Ehlers-Danlos syndrome type IV: report of two cases and review of the literature.  

PubMed Central

Two patients with previously undiagnosed Ehlers-Danlos syndrome type IV (EDS IV) presented acutely with clinical features suggestive of hypovolemic shock. Emergency laparotomies in both of them revealed spontaneous rupture of the common iliac arteries. The clinical features, operative findings, surgical approach, outcome and implications are discussed. Images Figure 1 Figure 2 Figure 3 PMID:11320937

Habib, K.; Memon, M. A.; Reid, D. A.; Fairbrother, B. J.

2001-01-01

155

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

156

Ruptured uterus: an ongoing tragedy of motherhood.  

PubMed

This study aimed to determine the frequency of ruptured uterus, possible aetiologic factors, foetomaternal out come and changes in obstetric care proposed to reduce this catastrophy. From September 1994 to September 1999 in Dhaka Medical College Hospital 39,782 deliveries occurred. All delivery records were reviewed and rupture uterus cases were identified. The result was compared with studies carried out in home and abroad. During the five years period among 39,782 deliveries 424 cases were of rupture uterus with a frequency of 1/93 deliveries. Eighty three percent rupture occurred in intact uterus and 17% occurred in uteri scarred by caesarian section. Common contributing factors were -prolonged/obstructed labour, grand multiparity, injudicious use of uterine stimulants, mismanaged labour by traditional birth attendant, delayed referral to well equipped centre, poor communication, poverty and ignorance. PMID:11942487

Khanam, R A; Khatun, M

2001-08-01

157

Mathematical simulation of the RBMK reactor pressure tubes ruptures during accidents: Computer code and verification  

SciTech Connect

The multiple rupture of the pressure tubes is the most dangerous accident of the channel reactors. There are about 2,000 channels in the RBMK. There exist two potential scenarios: (1) the case of accident when a group of channels becomes overheated; and (2) the case of accident with a rupture of one tube and shock loads on several adjacent channels. The described model considers the prediction technique for potential ruptures according to the first scenario. The probabilistic approach was applied due to existing of substantial scatter and uncertainties in parameters determining pressure tubes deformations and failure in accidents. It was founded on the randomization of the deterministic solution for pressure tube-graphite system deformation and rupture for varied values of chosen chance characters. The mathematical model for the deterministic solution considers the deformation of the system consisting of the pressure tube from the zirconium alloy containing 2.5% of niobium, graphite hard contact rings and graphite blocks. It was solved the common plane strain boundary task. Tube deformation includes three stages: tube deformation until the radial clearance between the tube and graphite disappears; tube deformation with metal flow into the vertical clearance in hard contact rings slits after disappearing of the radial clearance; deformation of the pressure tube-graphite system after closure of the radial clearance up to graphite failure. The mathematical model for the 1st scenario is described. The approach for code verification is also described.

Tkachev, V.V.; Zheltukhin, K.K. [Russian Research Center Kurchatov Inst., Moscow (Russian Federation). Inst. Nuclear Reactors

1996-07-01

158

Woman Health; Uterus Rupture, Its Complications and Management in Teaching Hospital Bannu, Pakistan  

PubMed Central

ABSTRACT Objectives: To evaluate risk factors, management, maternal and fetal outcomes of ruptured uterus at Women and Children Teaching Hospital Bannu, Pakistan. Study design: The prospective observational study was designed from January 2009 to December 2009. A total 64 patients were found with ruptured uterus evaluated in Women and Children Teaching Hospital Bannu, Pakistan. The aim of the study was to evaluate risk factors, management, maternal and fetal outcomes. Results: Frequency of ruptured uterus in hospital was found in 9/ 1000 deliveries, higher than most other studies. Amongst etiological factors the most important were great multiparity 27 (42.2%), injudicious use of Oxytocin 33 (51.6%), obstructed labour 8 (12.5%) and previous caesarean section 12 (18.8%). Of the total number of patients, 49 (76.6%) underwent abdominal hysterectomy (either subtotal or total), 3.1% of them needed bladder repair and 15.6% underwent repair of uterus. 5 (7.8%) died either due to irreversible shock or disseminated intravascular coagulation, 4% of patients had incontinence of urine, 53 (82.8%) of cases delivered dead babies and 9 (14.1%) had severe birth asphyxia needing neonatal intensive care. Conclusion: Uterine rupture is amongst the preventable obstetric complication that carries severe risks both to the mother as to the baby. Health education of people, training and supervision of health personal may reduce incidence especially in remote areas. PMID:23118819

QAZI, Qudsia; AKHTAR, Zubaida; KHAN, Kamran; KHAN, Amer Hayat

2012-01-01

159

Supershear Rupture Propagation in Homogeneous, Monolithic Media: Experimental Observations  

Microsoft Academic Search

The rupture speeds obtained by fracture experiments of monolithic brittle materials are usually by far lower than those predicted by theories and inferred from inversions of seismograms: Some seismic inversions even suggest the existence of supershear rupture speeds (i.e., rupture propagating faster than the relevant shear wave). Exceptionally, a few laboratory experiments of dynamic rupture on pre-cut interfaces do indicate

K. Uenishi

2006-01-01

160

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

161

Uterine rupture revisited: Predisposing factors, clinical features, management and outcomes from a tertiary care center in Turkey  

PubMed Central

Objective: To determine the predisposing factors, modes of clinical presentation, management modalities and fetomaternal outcomes of uterine rupture cases at a tertiary care center in Turkey. Methodology: A 14-year retrospective analysis of 61 gravid (>20 weeks of gestation) uterine rupture cases between January 1998 to March 2012 was carried out. Results: The incidence of ruptured uteri was calculated to be 0.116%. Persistence for vaginal delivery after cesarean was the most common cause of uterine rupture (31.1%). Ablatio placenta was the most common co-existent obstetric pathology (4.9%). Bleeding was the main symptom at presentation (44.3%) and complete type of uterine rupture (93.4%) was more likely to occur. Isthmus was the most vulnerable part of uterus (39.3%) for rupture. The longer the interval between rupture and surgical intervention, the longer the duration of hospitalization was. Older patients with increased number of previous pregnancies were likely to have longer hospitalization periods. Conclusion: Rupture of gravid uterus brings about potentially hazardous risks. Regular antenatal care, hospital deliveries and vigilance during labor with quick referral to a well-equipped center may reduce the incidence of this condition. PMID:24353622

Turgut, Abdulkadir; Ozler, Ali; Siddik Evsen, Mehmet; Ender Soydinc, Hatice; Yaman Goruk, Neval; Karacor, Talip; Gul, Talip

2013-01-01

162

[Misdiagnosed rupture of the diaphragm following blunt thoracic-abdominal trauma].  

PubMed

The histories of 67 patients with a diaphragmatic rupture due to blunt trauma were reviewed in four hospitals. In 45 patients the diagnosis was made within 24 hours after the accident, in the other 22 patients the rupture was diagnosed in a later stage. In the first group there were much abdominal injuries and during emergency laparotomy for some other reasons in 29% of these cases the diaphragmatic rupture was found accidentally. Not recognizing a rupture in the acute phase and therefore delaying operation was caused by the fact that the initial chest X-ray was not thoroughly checked for signs of a diaphragmatic rupture. The reasons for operation in the "delayed" group were mainly typical abnormalities for diaphragmatic rupture of the chest X-rays and other investigations proving the diagnosis. Only in one patient the delay in diagnosis has led to a very serious complication: because of incarceration with gangrene of a part of the small bowel it was necessary to remove this part. The other 21 patients in the group where the diagnosis was initially missed did not suffer from any serious complication. PMID:3424459

van Loenhout, R M; Carol, E J; Lubbers, E J; Reinders, J F; van der Werken, C

1987-10-01

163

Changing views of the biomechanics of vulnerable plaque rupture: a review.  

PubMed

This review examines changing perspectives on the biomechanics of vulnerable plaque rupture over the past 25 years from the first finite element analyses (FEA) showing that the presence of a lipid pool significantly increases the local tissue stress in the atheroma cap to the latest imaging and 3D FEA studies revealing numerous microcalcifications in the cap proper and a new paradigm for cap rupture. The first part of the review summarizes studies describing the role of the fibrous cap thickness, tissue properties, and lesion geometry as main determinants of the risk of rupture. Advantages and limitations of current imaging technologies for assessment of vulnerable plaques are also discussed. However, the basic paradoxes as to why ruptures frequently did not coincide with location of PCS and why caps >65 ?m thickness could rupture at tissue stresses significantly below the 300 kPa critical threshold still remained unresolved. The second part of the review describes recent studies in the role of microcalcifications, their origin, shape, and clustering in explaining these unresolved issues including the actual mechanism of rupture due to the explosive growth of tiny voids (cavitation) in local regions of high stress concentration between closely spaced microinclusions oriented along their tensile axis. PMID:23842694

Cardoso, Luis; Weinbaum, Sheldon

2014-02-01

164

Mechanics of 3-D shear cracks between Rayleigh and shear wave rupture speeds  

NASA Astrophysics Data System (ADS)

Though mode II shear fractures (primarily strike-slip earthquakes) can not only exceed the shear wave speed of the medium, but can even reach the compressional wave speed, steady-state calculations showed that speeds between the Rayleigh and shear wave speeds were not possible, thus defining a forbidden zone. For more than 30 years it was believed that this result in which the rupture jumps over the forbidden zone, also holds for 3-D ruptures, in which mode II and mode III (mainly dip-slip faulting) are mixed. Using unprecedentedly fine spatial and temporal grids, we show that even in the simple configuration of homogeneous fault properties and linear slip-weakening friction law, a realistic 3-D rupture which starts from rest and accelerates to some higher velocity, actually does pass smoothly through this forbidden zone, but very fast. The energy flux from the rupture tip is always positive, even within the so-called forbidden zone, contrary to the 2-D case. Finally, our results show that the width of the cohesive zone initially decreases, then increases as the rupture exceeds the shear wave speed and finally again decreases as the rupture accelerates to a speed of ˜90% of the compressional wave speed.

Bizzarri, Andrea; Das, Shamita

2012-12-01

165

Spontaneous rupture of tubal leiomyoma causing haemoperitoneum.  

PubMed

Leiomyomas are benign tumours that usually originate from the genital tract organs, particularly from the uterus. Spontaneous rupture of leiomyomas is a relatively rare condition. Herein, we report a 70 years old lady who was admitted through the emergency room with sudden abdominal pain. A ruptured mass originating from the fallopian tube, causing haemoperitoneum was revealed at laparotomy. Pathological examination revealed cellular leiomyoma. PMID:24906284

Ozkan, Zeynep; Gonen, Ayse Nur; Emir, Seyfi; Yazar, Fatih Mehmet; Gul, Evrim; Artas, Zeynep Dogan; Aslan, Ozgen; Artas, Hakan

2014-05-01

166

Ruptured spontaneous splenic artery aneurysm: A case report and review of the literature  

PubMed Central

INTRODUCTION Splenic artery aneurysm is a rare condition, however, potentially fatal. The importance of splenic artery aneurysm lies in the risk for rupture and life threatening hemorrhage. PRESENTATION OF CASE This is a case of a ruptured splenic artery aneurysm in a 58-year-old lady. She presented with hypovolemic shock and intra-peritoneal bleeding. Diagnosis was confirmed by CT angiography and she was managed by operative ligation of the aneurysm with splenectomy and distal pancreatectomy. DISCUSSION The literature pointed the presence of some risk factors correlating to the development of splenic artery aneurysm. In this article we discuss a rare case of spontaneous (idiopathic) splenic artery aneurysm and review the literature of this challenging surgical condition. CONCLUSION Splenic artery aneurysm needs prompt diagnosis and management to achieve a favorable outcome, high index of suspicion is needed to make the diagnosis in the absence of known risk factors. PMID:25240215

Abdulrahman, Aisha; Shabkah, Alaa; Hassanain, Mazen; Aljiffry, Murad

2014-01-01

167

Toxic Shock Syndrome  

MedlinePLUS

... about it, then take some precautions. What Is Toxic Shock Syndrome? If you're a girl who's ... period, you may have heard frightening stories about toxic shock syndrome (TSS), a serious illness originally linked ...

168

The Heliospheric Termination Shock  

E-print Network

The heliospheric Termination Shock is the largest (by dimension) shock in the heliosphere. It is believed that it is also the strongest shock and is responsible for the generation of the Anomalous Cosmic Ray component in the heliosphere. This chapter review the gross properties and observations of the Termination Shock. It is structured as follows: 1. The heliosphere, providing the heliospheric stage for Termination Shock formation, 2. The argument for a heliospheric Termination Shock, 3. The global heliospheric system, 4. Termination Shock properties, 5. Observations: the Voyager passages, radio observations, plasma waves and electron beams, traces of plasma and magnetic field, energetic particles, galactic cosmic rays, Termination Shock particles, the anomalous cosmic ray component, 6. Conclusions.

R. A. Treumann; C. H. Jaroschek

2008-07-25

169

Shock compression of solids  

Microsoft Academic Search

This review contains a brief, comprehensive, critical assessment of the status of investigations concerning the response of solids to shock compression. Mechanical, metallurgical, electrical, optical and other phenomena occurring in substances subjected to shock pressures covering the range from about 0.1 to 6000 GPa are considered. Emphasis is placed on physical interpretation of observations peculiar to the shock environment and

Lee Davison; R. A. Graham

1979-01-01

170

Concepts of Shock Waves  

Microsoft Academic Search

Shock Waves Definition and Formation Properties of Sonic Waves Formation of a Shock Wave Rankine-Hugoniot Equations (Conservation Laws) Conservation of Mass, Momentum and Energy in the Laboratory Frame The Same in the Shock Front Frame The Same in Special Relativity Hugoniot Curve and Its Representation in the (P, up) Plane Comments on Conservation Laws and Relative Position of Hugoniot and

A. Miigault

1998-01-01

171

Life Shocks and Homelessness  

Microsoft Academic Search

We exploit an exogenous health shock—the birth of a child with a severe health condition—to investigate the causal effect of a life shock on homelessness. Using survey data from the Fragile Families and Child Wellbeing study that have been augmented with information from hospital medical records, we find that the health shock increases the likelihood of homelessness three years later,

Marah A. Curtis; Hope Corman; Kelly Noonan; Nancy Reichman

2011-01-01

172

Blood Chemical Abnormalities in Cattle with Ruptured Bladders and Ruptured Urethras  

PubMed Central

A study was undertaken to determine the blood chemical variables and compare changes that occurred with ruptured bladders and ruptured urethras in steers and yearling bulls. The fatality rates were 10.5% in steers with ruptured urethras and 50.8% in steers with ruptured bladders. Both groups had significantly decreased serum sodium and chloride values and significantly increased serum creatinine, blood urea nitrogen, and plasma protein concentrations compared to the normal group. Steers with ruptured bladders were more dehydrated, had significantly lower serum sodium and chloride values and had significantly higher blood urea nitrogen concentrations than steers with ruptured urethras. The combination of a decreased serum sodium, a decreased serum chloride, and a decreased ratio of serum phosphate to blood urea nitrogen occurred consistently within the ruptured bladder group. Of the variables examined, serum phosphate was the best prognostic indicator in the steers with ruptured bladders as all of the steers that died had a serum phosphate in excess of 2.9 mmol/L. The fluid and electrolyte changes are discussed. PMID:17422206

Donecker, J. M.; Bellamy, J. E. C.

1982-01-01

173

Kinematic Rupture Process Of Karakocan-Elazig Earthquake, Eastern Turkey  

NASA Astrophysics Data System (ADS)

An earthquake (Mw=5.9) hit Elazig in the eastern part of Turkey on March 8, 2010 at 02:32 (GMT). It is located midway between the provincial capital of Elaz?? and Bingöl with coordinates reported as 38o48.42N and 40o5.99E by Bogazici University Kandilli Observatory and Earthquake Research Institute (KOERI). Source characterization and slip history were estimated the main and four moderate size earthquake almost at the same location. The earthquake occurred at one of the tectonically very active East Anatolian Fault zone starts at the Karl?ova triple junction, where it meets the North Anatolian fault to the NE. Multi time-window linear waveform inversion technique (MTWIT) was applied to strong ground motion (SGM) data. Theoretical Green's functions between subfaults and stations were calculated by a Discrete Wave Number Method (DWNM) using 1-D velocity structure. Inversion technique used in this study yields a non unique solution. Therefore various rupture models have been tried until both observed and synthetic data were matched. Results show simple patterns in slip distributions. Maximum slip is 0.78 and seismic moment is 1.435E+25 dyne.cm from the kinematic rupture process of the strike slip faulting. In this study, we searched a stable 1-D crustal velocity model with low RMS misfit to construct the theoretical Green's function between each sub-fault and each station among the 4 different models. These are Preliminary Reference Earth Model (PREM; Dziewonski and Anderson, 1981), International Association of Seismology and the Physics of the Earth's Interior (IASP91) (Kennett and Engdahl, 1991), Kandilli Observatory and Earthquake Research Institute (KOERI) earthquake location model, explosion model (Gurbuz, 2004). We have collected previous studies Rebollar et al., (2001), Ichinose et al., (1997), Abdel-Fattah (2002), Somerville et al., (1999), Wells and Coppersmith (1994) on source information of moderate size earthquakes occurred worldwide and compared with our results. Results were compared with those of similar size earthquakes around the world and a new empirical relationship was proposed between seismic moment and rupture area. We expect our findings provide usefull information to resolving rupture mechanisms and triggering of the events in Eastern Anatoion Region. Key Words: Rupture Process, Elazig Earthquake, Eastern Turkey

Bekler, F. N.; Ozel, N. M.; Tanircan, G. B.

2012-04-01

174

Spontaneous splenic rupture in a patient with small-cell lung cancer.  

PubMed

We report a case of a 66-year-old male patient presented to our pneumology ward with the diagnosis of neutropenic pneumonia. Therapy with granulocyte colony stimulating factors (G-CSF) and intravenous antibiotics was initiated as usual in this condition. The unexpected and acute onset of left-sided abdominal pain and sings of hypovolemic shock led us to a challenging diagnosis, rarely considered in non-traumatic patients. After pathological evaluation of the spleen, spontaneous splenic rupture due to G-CSF was our final diagnosis. PMID:23907972

Fernandes, Lígia Rodrigues; dos Santos, Cláudia Lares; Costa, Filipa; Barata, F

2013-01-01

175

[Renal angiomyolipoma rupture as a cause of lumbar pain: report of one case].  

PubMed

Renal angiomyolipoma is a benign tumor formed by smooth muscle, adipose tissue and blood vessels. It is commonly found incidentally and its clinical manifestations are pain and abdominal mass or spontaneous tumor rupture with retroperitoneal bleeding. The clinical presentation of a hemorrhagic shock secondary to a retroperitoneal hematoma is uncommon. We report a 40 year-old male who presented to the emergency room with lumbar pain and deterioration of hemodynamic parameters. The CT scan showed a left renal injury associated to an expansive retroperitoneal process. The abdominal exploration, vascular control of the renal pedicle and nephrectomy allowed a successful outcome. PMID:18949188

Cifuentes, Melissa; Calleja, Félix; Hola, José; Daviú, Antonio; Jara, Danilo; Vallejos, Humberto

2008-08-01

176

Recurrence Characteristics of 'Full Rupture' Earthquakes  

NASA Astrophysics Data System (ADS)

A prime goal in earthquake geology is to identify the recurrence characteristics of full rupture earthquakes (earthquakes that rupture the full down-dip extend of the seismogenic zone and potentially beyond it) along a given fault. Paleoseismology and tectonic geomorphology enable to extend the seismic record by centuries or millennia --for events that are sufficiently large to disrupt the earth surface. Unfortunately, long records are rare and it is generally difficult to make statistically meaningful statements on recurrence characteristics. Furthermore, the paleoseismic and geomorphic records may also contain partial rupture earthquakes (events that may rupture ground surface but do not activate the full seismogenic width) and by that the masking signal of the full rupture events (as I will show in my presentation, those partial rupture events exhibit different recurrence characteristics than the full rupture events). Physics-based earthquake simulators provide the means to study the long-term behavior of a (simulated) fault with respect to the implemented boundary conditions (e.g., fault geometry, loading conditions, frictional behavior). Here, I present a numerical study on earthquake recurrence characteristics as a function of fault geometric roughness (considered a proxy for fault maturity) and by that as a function of fault interaction and connectivity. Focus was on magnitude-frequency distribution and fault segmentation as a function of roughness. I find that bimodality in magnitude frequency relation --the largest earthquakes occurring more frequently than anticipated from the Gutenberg-Richter relation-- is tightly linked to the structural maturity of a fault. Bimodal seismic behavior and maximum earthquake size increases as fault roughness decreases. Furthermore, the variability of large earthquake rupture characteristics of a given fault decreases with structural maturation and major earthquakes along spatially isolated faults exhibit inherent periodicity. While slip at a point along a fault is variable per se, variability becomes increasingly systematic as the fault matures. Based on my results and supported by paleoseismic data, I propose that previously presented earthquake recurrence models (uniform slip-, and characteristic earthquake model) generalize the seismic behavior of faults with different structural age and fault-system complexity and are characterized by alternating single-segment and multi-segment rupture probability.

Zielke, O.

2013-12-01

177

Coronal shock waves  

NASA Technical Reports Server (NTRS)

The formation of magnetohydrodynamic (MHD) shocks near the leading edge of Coronal Mass Ejections (CME's) is considered using results from both shock theory and numerical simulations. By using just the shock theory results and a simplified model corona, the following is shown: a slow shock front should be concave upward (away from the solar surface); a configuration containing intermediate shocks should also be concave upward near the center of the CME and concave downward at some distance from the CME centerline; and a fast shock configuration should be concave downward. These results are verified with numerical simulations of the MHD equations for the propagation of shocks through a quiescent coronal streamer. By examining the characteristic wave speeds in the ambient streamer, it is estimated that the various shock configurations should form for CME speeds within the following speed increments: slow shocks, 200 to 300 km/sec; intermediate shocks, 300 to 900 km/sec; and fast shocks, greater than 900 km/sec.

Steinolfson, Richard S.

1992-01-01

178

Caring for people with carotid artery rupture.  

PubMed

In the second of three articles, the authors discuss the care of people with carotid artery rupture. Carotid artery rupture is a potentially fatal condition that requires swift action on the part of the nurse who is present. The size of the rupture and the prognosis for the individual patient determines whether or not active resuscitation is undertaken. The multi-professional team should decide, in advance of an impending rupture, on the optimum plan of care. Calm, careful explanations should be given to patients and relatives and the decision regarding resuscitation should be recorded in the patient's notes. In the event of unforeseen circumstances where a rupture occurs, an active nursing care plan should be instituted and care taken to keep relatives well informed. The patient's airway should be kept clear through the use of suctioning, inflation of tracheostomy tube cuff and correct positioning. Sedative drugs and palliative care may subsequently be necessary. Support and help should be given to all who witness or are involved in the care of these patients. PMID:16415744

Frawley, Theresa; Begley, Cecily M

179

[Traumatic rupture of the corpus cavernosum].  

PubMed

Traumatic rupture of the corpus cavernosum is relatively frequent in the authors' experience. Based on the study of a series of 80 cases and a review of the literature, the authors analyse the diagnostic and therapeutic aspects and outcome of this disease. The patients in this series had a mean age of 30 years. Meticulous and intimate clinical interview demonstrated that the commonest mechanism is forced manipulation of the erect penis (68%). Clinical examination localized the site of the fracture (proximal: 57%, distal 43%). The fracture was unilateral (78 cases), rarely bilateral (2 cases) and associated with complete rupture of the urethra (1 case). Treatment was surgical in 79 patients. A distal semicircumferential incision was used in the case of bilateral rupture, distal rupture and associated urethral lesion (34 cases). A favourable course was observed in 86% of cases. However, 9 postoperative complications (12.5%) were observed (6 cases of fibrous plaques, 3 cases of chordee of the penis), due either to the extent of the haematoma or to the delay in treatment. Traumatic rupture of the corpus cavernosum is a disease of young adults, which requires early surgical treatment with an approach adapted to the type of lesions. PMID:9834519

Bennani, S; Dakir, M; Debbagh, A; Hafiani, M; el Moussaoui, A; el Mrini, M; Benjelloun, S

1998-09-01

180

Coseismic thrusting rupture and slip distribution produced by the 2008 M w 7.9 Wenchuan earthquake, China  

Microsoft Academic Search

Field investigations reveal that the Mw 7.9 Wenchuan (China) earthquake of 12 May 2008 produced a 285-km-long surface rupture zone, with dominantly thrusting slip accompanied by a right-lateral component along the central-northern segments of the zone, and left-lateral component along the southern segment, along the Longmen Shan Thrust Belt, eastern margin of the Tibetan Plateau. The co-seismic ruptures mainly occurred

Aiming Lin; Zhikun Ren; Dong Jia; Xiaojun Wu

2009-01-01

181

Investigation of time-to-rupture of polymethyl methacrylate under the combined influence of active liquid media and ?-radiation  

Microsoft Academic Search

Time-to-rupture and creep of polymethyl methacrylate (PMM) under the combined influence of stress, active liquid media, and ?-radiation were studied. It was shown that time-to-rupture of PMM under these conditions is determined mainly by the influence of the working medium when the absorbed radiation dose is less than about 10 Mrads and that ?-radiation increases the creep rate of PMM

A. N. Tynnyi; Z. A. Bazilevich; S. I. Mikitishin; Ya. I. Lavrentovich; G. V. Karpenko

1972-01-01

182

Spontaneous rupture of splenic vein in a pregnant woman during a religious ritual  

Microsoft Academic Search

The treatment of retroperitoneal hemorrhage can be by surgical or a conservative approach but the main problems about these cases are difficulty in diagnosis due to negative results after abdominal lavage and the difficulties in accessing the retroperitoneal area surgically. Retroperitoneal hemorrhage during pregnancy, occurring as a result of spontaneous rupture, is very rare event. Such cases require urgent operation

Nursen Turan; Fatih Oghan; Tansev Boran

2007-01-01

183

Fundamentals of collisionless shocks for astrophysical application, 1. Non-relativistic shocks  

NASA Astrophysics Data System (ADS)

A comprehensive review is given of the theory and properties of nonrelativistic shocks in hot collisionless plasmas—in view of their possible application in astrophysics. Understanding non-relativistic collisionless shocks is an indispensable step towards a general account of collisionless astrophysical shocks of high Mach number and of their effects in dissipating flow-energy, in heating matter, in accelerating particles to high—presumably cosmic-ray—energies, and in generating detectable radiation from radio to X-rays. Non-relativistic shocks have Alfvénic Mach numbers {{fancyscript{M}}_A? sqrt{m_i/m_e}(?_{pe}/?_{ce})}, where m i / m e is the ion-to-electron mass ratio, and ? pe , ? ce are the electron plasma and cyclotron frequencies, respectively. Though high, the temperatures of such shocks are limited (in energy units) to T < m e c 2. This means that particle creation is inhibited, classical theory is applicable, and reaction of radiation on the dynamics of the shock can be neglected. The majority of such shocks are supercritical, meaning that non-relativistic shocks are unable to self-consistently produce sufficient dissipation and, thus, to sustain a stationary shock transition. As a consequence, supercritical shocks act as efficient particle reflectors. All these shocks are microscopically thin, with shock-transition width of the order of the ion inertial length ? i = c/ ? pi (with ? pi the ion plasma frequency). The full theory of such shocks is developed, and the different possible types of shocks are defined. Since all collisionless shocks are magnetised, the most important distinction is between quasi-perpendicular and quasi-parallel shocks. The former propagate about perpendicularly, the latter roughly parallel to the upstream magnetic field. Their manifestly different behaviours are described in detail. In particular, although both types of shocks are non-stationary, they have completely different reformation cycles. From numerical full-particle simulations it becomes evident that, on ion-inertial scales close to the shock transition, all quasi-parallel collisionless supercritical shocks are locally quasi-perpendicular. This property is of vital importance for the particle dynamics near the quasi-parallel shock front. Considerable interest focusses on particle acceleration and the generation of radiation. Radiation from non-relativistic shocks results mainly in wave-wave interactions among various plasma waves. Non-thermal charged particles can be further accelerated to high energies by a Fermi-like mechanism. The important question is whether the shock can pre-accelerate shock-reflected particles to sufficiently high energies in order to create the seed-population of the non-thermal particles required by the Fermi mechanism. Based on preliminary full-particle numerical simulations, this question is answered affirmatively. Such simulations provide ample evidence that collisionless shocks with high-Mach numbers—even when non-relativistic—could probably by themselves produce the energetic seed-particle population for the Fermi-process.

Treumann, R. A.

2009-12-01

184

Splay fault surface rupture triggered by the 2010 Chile earthquake  

NASA Astrophysics Data System (ADS)

Faults that splay from megathrusts have been imaged at several active plate boundaries and observed on exposed fossil sections. Due to their steep dip, slip along such structures triggered by a megathrust earthquake may enhance near-field tsunami waves and shorten arrival times. However, motion of splay faults and their role on seismotectonic segmentation has remained elusive due to their predominant offshore location and few historical accounts. Though splay fault slip has been inferred during the 2004 Sumatra and other events, surface ruptures triggered by the 1964 M9.2 Alaska earthquake have been the only documented so far. Here we use field, geodetic and InSAR data to document surface fault rupture and coastal tilting at Isla Santa Maria (ISM; 37S) during the M8.8 earthquake of February 27, 2010. We integrate the observed deformation with previous knowledge of the regional structure to propose triggering of a splay fault. ISM is 75 km inland from the trench, at the intersection of the Arauco Bay and Santa María fault systems (SMFS), both consisting of blind reverse faults that propagate folds. The SMFS is associated to a cluster of microseismicity extending from the plate interface at 15 km to 2 km depth. An offshore seismic reflection profile across this cluster images a main reverse fault with a flat-ramp-flat structure shortcutting to the footwall. The 2010 surface breaks extend across the entire northern part of the island for 900 m, divided in two domains of ENE-WSW oriented structures separated by an E-W striking transfer zone. Each domain consists of faults and fractures with en echelon patterns, with a maximum normal vertical displacement of 80 cm. The geometry of surface ruptures is consistent with dextral transtensional kinematics. We associate the surface breaks to transpressional growth of the fault-cored anticline northeast of ISM; transtension at the surface relates to fold bending. Surface rupture was accompanied by 1.6-2.2 m of coastal uplift and a northward tilt revealed by ALOS InSAR data, biomarkers, campaign GPS, and leveling of a benchmark. This pattern of tilting mimics that of emerged late Holocene beach ridges, and is rather associated to motion along the Arauco Bay fault. Both systems may have been triggered by the megathrust event. Alternatively, it could arise at the sharp edge of a patch of high megathrust slip. Prominent rush of fluids from the rupture started during the Maule earthquake and continued for weeks. A small lake adjacent to the rupture, dry during summer droughts, became filled by the offspring. The flat morphology leads to small drainage basins with barely sufficient water to supply inhabitants during dry summer months suggesting that fluids rose through the fault from deeper levels in the crust. The SMFS is associated to the position of a paleo backstop structure, which limited an older deformable domain from the stable continental framework. The SMFS branches upward near the updip limit of the seismogenic zone, where fluids are expelled from mineral transformations. The Maule earthquake may have released trapped fluids at depth, which migrated through the splay fault reducing its friction and facilitating fault slip and surface rupture.

Melnick, D.; Moreno, M.; Motagh, M.; Cisternas, M.

2010-12-01

185

Component external leakage and rupture frequency estimates  

SciTech Connect

In order to perform detailed internal flooding risk analyses of nuclear power plants, external leakage and rupture frequencies are needed for various types of components - piping, valves, pumps, flanges, and others. However, there appears to be no up-to-date, comprehensive source for such frequency estimates. This report attempts to fill that void. Based on a comprehensive search of Licensee Event Reports (LERs) contained in Nuclear Power Experience (NPE), and estimates of component populations and exposure times, component external leakage and rupture frequencies were generated. The remainder of this report covers the specifies of the NPE search for external leakage and rupture events, analysis of the data, a comparison with frequency estimates from other sources, and a discussion of the results.

Eide, S.A.; Khericha, S.T.; Calley, M.B.; Johnson, D.A.; Marteeny, M.L.

1991-11-01

186

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. PMID:22896777

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

2012-01-01

187

Acoustic levels of heavy truck tire ruptures.  

PubMed

Transportation vehicles, whether they are passenger vehicles or heavy trucks and transport vehicles, rely upon rubber tires to negotiate the roadways and surfaces on which they are driven. These tires have the potential of sudden rupture resulting from various causes including but not limited to over-pressurization, sidewall failures, or punctures from roadway debris. These rupture events can and do occur while the vehicles are stationary (e.g., during servicing) or are being driven, and often occur without notice. While the phenomenon of sudden tire failure has been documented for several decades, the potential bodily injury which can occur when an individual is in close proximity to such a sudden rupture has only more recently been documented. Aside from anecdotal mention in case studies, there has been little quantitative information available on the acoustic levels during these failures. Our study provides measured acoustic levels as a function of distance for such catastrophic tire failures. PMID:23622472

Wood, Matthew; Woodruff, William

2013-05-01

188

Ruptured venous aneurysm of cervicomedullary junction  

PubMed Central

Background: Ruptured venous aneurysm is often seen with arterio-venous malformation (AVM) or developmental venous anomaly (DVA). However, isolated venous aneurysm is unusual. Case Description: We present a case of ruptured venous aneurysm that presented with subarachnoid hemorrhage (SAH) and intraventricular hemorrhage (IVH). Digital substraction angiography (DSA) revealed a saccular contrast filling pouch in the left lateral aspect of cervicomedullary junction (CMJ). Endovascular intervention was not a viable option. During surgery, a saccular pliable structure approx. 1.5 × 1 cm was found in the subarachnoid space that was clipped and excised. There were no arterial feeders, no evidence of surrounding AVM, and no dilated perimedullary vein. Conclusion: This is perhaps the first reported case of ruptured venous aneurysm (without associated AVM) of CMJ, which was successfully managed surgically. The possible etiologies remain an unnoticed head trauma or a congenital vessel wall abnormality. Surgically clipping and excision remains the treatment of choice for such lesion. PMID:24575317

Aggarwal, Ashish; Salunke, Pravin; Futane, Sameer; Mathuriya, S. N.; Kumar, Ajay; Mukherjee, K. K.; Radotra, B. D.

2014-01-01

189

Myocardial Rupture following Carbon Monoxide Poisoning  

PubMed Central

We present the first case of severe cardiotoxicity of carbon monoxide leading to myocardial rupture and fatal outcome. 83-year-old woman was hospitalized 4 hours after the fire in her house with no respiratory or cardiac symptoms. After two days, she has suffered sudden collapse leading to cardiac arrest. Postmortem examination revealed intramural haemorrhage with myocardial rupture at the apex of the left ventricle. Minimal stenosis was noted in the proximal coronary arteries with no evidence of distal occlusion or any other long-standing heart disease. This case supports recommendations for targeted cardiovascular investigations in cases of CO poisoning. PMID:25110594

Dragelyte, Gabija; Plenta, Juris; Chmieliauskas, Sigitas; Jasulaitis, Algimantas; Raudys, Romas; Jovaisa, Tomas; Badaras, Robertas

2014-01-01

190

Modeling rupture segmentations on the Cascadia megathrust  

NASA Astrophysics Data System (ADS)

The Cascadia subduction zone has produced a series of large to great earthquakes, most recently in 1700 AD. Paleoseismological studies of submarine turbidites suggest a significant difference in recurrence interval between Northern (~500 year) and Southern (~200-300 year) Cascadia. Whether future large ruptures are segmented is very important for estimating hazard in Pacific Northwest, but remains enigmatic from the interpretations of current locking maps. Our approach is to develop rupture scenarios of Cascadia earthquakes by performing numerical simulations using the finite element software, PyLith. Based on the USGS plate interface model of Cascadia, we have constructed a realistic three-dimensional subduction fault model that stretches from Northern California to Central Vancouver Island. We have performed a number of dynamic rupture simulations using a set of artificial friction parameters and uniform stress distributions on the fault governed by a slip-weakening friction law. Preliminary results show that ruptures have initiated from the nucleation zone with higher shear stress than the ambient fault and have propagated on the realistic three-dimensional fault surface. The increase of dip angle with depth has little effect on the rupture propagation because that is governed mostly by the fault strength. The along-strike bend of the fault beneath Washington state and Vancouver Island has not impeded the rupture propagation given the uniform fault strength. To estimate the possible rupture segmentation, we have converted a slip-deficit rate model derived from GPS data into stress change distributions on the fault assuming the entire slip deficit would be released in the next great earthquake. We are also constructing another initial stress map derived from tidal and leveling data, which shows a significant difference in the locking depth beneath Central Oregon. The other important variable, the spatial variation of frictional parameters, however, has to be determined under certain assumptions. We assume the critical distance, Dc, is proportional to the final slip, thus will be obtained from the slip deficit distribution. By combining the estimated stresses and Dc for the slip-weakening relation, we will investigate how the different interseismic locking profiles could influence possible segmentation for future ruptures on the Cascadia megathrust. This work is supported by FM Global.

Yang, H.; Liu, Y.; McGuire, J. J.

2012-12-01

191

[Apophyseal rupture of ischial bone tuberosity].  

PubMed

The apophyses of the pelvic skeleton are the insertion zones of strong muscles and tendons and are soft points towards the end of growth. Apophyseal ruptures have quite often occurred as a consequence of overstressing in the context of certain athletic disciplines. Reported in this paper are two of the authors' own cases of apophyseal rupture of Tuber ossis ischii. Diagnosis is easy on the basis of case history, clinical manifestations, and X-ray. Treatment is conservative, with the patient hip-straightened confined to bed for three weeks. Surgery might be indicated in cases of continued seating problems or neurological failures. PMID:3577444

Lindner, H O; Winkeltau, G; Kalemba, J

1987-01-01

192

Interaction between shock wave and unsteady jet in shock tube  

Microsoft Academic Search

We have observed the interaction between a shock wave and an unsteady jet in shock tube. From the results of the experiment, we have reported that the interaction between the shock wave and the unsteady jet in a shock tube was very strong, and it temporarily generated a hemispherical reflected shock wave. However, we could not clarify the cause of

Yoshimi Ishii; Fumio Takayama

1990-01-01

193

Ion heating and energy redistribution across supercritical perpendicular shocks: Application to planetary and interplanetary shocks  

NASA Astrophysics Data System (ADS)

We investigate how the ion dissipative process across supercritical perpendicular shocks depends on the shock front micro-structures. At a collisionless plasma shock, the dissipation and micro-structure of the shock font are dominated by wave-particle interactions. Comparison of the ion thermalization at different kinds of shocks, e.g., planetary and interplanetary shocks, can quantify how much interaction is occurring at the shock boundary. Investigation of this problem for diverse solar wind (SW) conditions will yield important information on the dependences of the ion thermalization and energy redistribution on plasma parameters. With the aid of a successful automatic separation method [Yang et al., 2009], the incident ions at the shock can be divided into two parts: reflected (R) ions and directly transmitted (DT) ions. Corresponding heating efficiency of each population of ions at the shock can be calculated respectively. Wilkinson & Schwartz [1990] have theorized that the amount of reflected ions at perpendicular shocks depends on plasma parameters. Based on the Rankine-Hugoniot (R-H) conservation laws, they found that the fraction reflected is strongly dependent on the magnitude of the ratio of specific heat capacities ? chosen in the R-H relations. The main goal of this work is to investigate how the plasma parameters, e.g. the particle velocity distribution, the plasma beta value, seed populations, etc. (from a particle dynamic point of view), control the amount of reflected ions by using one-dimensional (1-D) full-particle-cell simulations. The simulation results may help to explain the ion heating efficiency and energy redistribution at shocks observed by Cluster, Wind, Voyager, etc.

Yang, Z.; Liu, Y. D.; Richardson, J. D.; Parks, G. K.

2013-12-01

194

Induced Metastable Memory in Heat Shock Response  

PubMed Central

We studied the dynamics of the Heat Shock Response (HSR) mechanism, and the persistence of a injury-protected state in the cell following the shocks, known as thermotolerance. A series of double shock experiments were performed on Chinese Hamster Ovary (CHO) cells, tracking the dynamics of some components of HSR pathway (the Hsp70 protein level and Hsp70 mRNA transcription rate). The main features of HSR dynamics were well reproduced by a simplified model of the chemical reaction pathways governing the HSR. In particular, the thermotolerance phenomenon could be well characterized by introducing a shock-dependent switch in mRNA halflife, that can be interpreted as a sort of primitive memory at the mRNA level. PMID:19669434

Remondini, D.; Bernardini, C.; Forni, M.; Bersani, F.; Bacci, M. L.

2006-01-01

195

Establishment of borehole observation system and high resolution seismic studies in the western part of the main Marmara Fault in the frame of MARSite Project  

NASA Astrophysics Data System (ADS)

The main objective of this study is to install a multi-parameter borehole system and surface array as close to the main Marmara Fault (MMF) in the western Marmara Sea as possible, and measure continuously the evolution of the state of the fault zone surrounding the MMF and to detect any anomaly or change which may occur before earthquakes by making use of the data from the arrays already running in the eastern part of the Marmara Sea. The multi-parameter borehole system will be composed of very wide dynamic range and stable borehole (VBB) broad band seismic sensor, and incorporate 3-D strain meter, tilt meter, and temperature and local hydrostatic pressure measuring devices. The borehole seismic station will use the latest update technologies and design ideas to record 'Earth tides' signals to the smallest magnitude -3 events. Bringing face to face the seismograms of microearthquakes recorded by borehole and surface instruments portrays quite different contents. The shorter recording duration and nearly flat frequency spectrum up to the Nyquist frequencies of borehole records are faced with longer recording duration and rapid decay of spectral amplitudes at higher frequencies of a surface seismogram. The main causative of the observed differences are near surface geology effects that mask most of the source related information the seismograms include, and that give rise to scattering, generating longer duration seismograms. In view of these circumstances, studies on microearthquakes employing surface seismograms may bring on misleading results. Particularly, the works on earthquake physics and nucleation process of earthquakes requires elaborate analysis of tiny events. It is obvious from the studies on the nucleation process of the 1999 earthquake that tens of minutes before the major rupture initiate noteworthy microearthquake activity happened. The starting point of the 1999 rupture was a site of swarm activity noticed a few decades prior the main shock. Nowadays, analogous case is probable in western Marmara Sea region, prone to a major event in near future where the seismic activity is prevailing along the impending rupture zone. Deploying a borehole system eastern end of the Ganos fault zone may yield invaluable data to closely inspect and monitor the last stages of the preparation stage of major rupture. Keywords: Borehole seismometer; Ganos fault; microearthquakes; western Marmara

Ozel, A.; Yalcinkaya, E.; Guralp, C. M.; Tunc, S.; Meral Ozel, N.

2013-12-01

196

Thermocapillary flow and rupture in films of molten metal on a substrate  

NASA Astrophysics Data System (ADS)

We consider fluid flow in thin films of molten metal resulting from irradiation by a Gaussian laser beam. Surface tension gradients due to nonuniform heating induce a flow of the molten liquid away from the center of the irradiated area, leading to formation of dry areas on the substrate. We develop a mathematical model of the flow under the assumption of the large ratio of laser beam radius to film thickness. The model extends the standard lubrication-type analysis to include the highly nonlinear dependence of evaporative flux on local interfacial temperature, unsteady heat conduction in the substrate, and positive disjoining pressure due to unbalanced contributions from the kinetic energy of free electrons in the metal. The latter is proportional to the inverse square of the film thickness. We identify thermocapillary stresses as the main mechanism of rapid removal of liquid metal from the irradiated area. Characteristic times of the process, as well as shapes of the molten region surface, agree with experimental observations. We investigate rupture of the molten film and find two different rupture scenarios. The melt surface can either touch the substrate at a point (point rupture) or along a line at a certain radial distance away from the center of the irradiated area (ring rupture). Nondimensional criteria for these two mechanisms are identified. In particular, we show that positive disjoining pressure promotes ring rupture.

Ajaev, Vladimir S.; Willis, David A.

2003-10-01

197

Thermocapillary flow and rupture in films of molten metal on a substrate  

NASA Astrophysics Data System (ADS)

We consider fluid flow in thin films of molten metal resulting from irradiation by a Gaussian laser beam. Surface tension gradients due to non-uniform heating induce a flow of the molten liquid away from the center of the irradiated area, leading to formation of dry areas on the substrate. We develop a mathematical model of the flow under the assumption of the large ratio of laser beam radius to film thickness. The model extends the standard lubrication-type analysis to include the highly nonlinear dependence of evaporative flux on local interfacial temperature, unsteady heat conduction in the substrate, and positive disjoining pressure due to unbalanced contributions from the kinetic energy of free electrons in the metal. We identify thermocapillary stresses as the main mechanism of rapid removal of liquid metal from the irradiated area. Characteristic times of the process, as well as shapes of the molten region surface, agree with experimental observations. We investigate rupture of the molten film and find two different rupture scenarios. The melt surface can either touch the substrate at a point (point rupture) or at points at a certain distance from the center of the irradiated area (ring rupture). Nondimensional criteria for these two mechanisms are identified. In particular, we show that positive disjoining pressure promotes ring rupture.

Ajaev, Vladimir; Willis, David

2003-11-01

198

Liminescence in water and glycerin in the field of spherically focused and plane shock-acoustic waves  

Microsoft Academic Search

The dynamics of luminescence generation and cavitation in the field of spherically focused and plane shock-acoustic waves\\u000a in water, glycerin, and their mixtures is studied. It is shown that in the spherical focusing of shock-acoustic waves, the\\u000a first pulse of luminescence correlates with cavitational rupture of the liquid. It is assumed that the registered luminescence\\u000a is caused by electrokinetic processes

V. S. Teslenko; G. N. Sankin; A. P. Drozhzhin

1999-01-01

199

Shock transformations in quartzite  

NASA Technical Reports Server (NTRS)

We report results of studies of experimental shock metamorphism in a quartzite sample. Shock pressure increases in the experiment from a rim to a center of the bowl-shaped sample due to a design of a recovery assembly. The section along an equatorial plane shows a progressive development of shock metamorphism. On the basis of observations, it is proposed that diaplectic glass can be a product of quenching a melt.

Badjukov, D. D.; Koslov, E. A.; Zhugin, Yu. N.; Abakshin, E. V.

1993-01-01

200

Simulations of collisionless shocks  

SciTech Connect

A problem of critical importance to space and astrophysics is the existence and properties of high-Mach-number (HMN) shocks. In this letter we present the results of simulations of perpendicular shocks with Alfven Mach number 22. We show that the shock structure is a sensitive function of resistivity, becoming turbulent when the resistivity is too low. We discuss the problem of electron heating, and the extension of our results to higher Mach numbers. 14 refs., 4 figs.

Quest, K.B.

1984-01-01

201

A ten-year review of ruptured sinus of valsalva: clinico-pathological and echo-Doppler features.  

PubMed

Rupture of the sinus of valsalva (RSOV) is an uncommon condition with a variety of manifestations ranging from an asymptomatic murmur to cardiogenic shock. This retrospective 10-year review (1985-1995) of 18 patients from a single institution revealed that 6 (33%) were female and 12 (67%) were male with a mean age of 37.6 +/- 13.4 years and that 72% were Chinese by ethnic descent with the remaining 28% being Malay. Eight patients (44.4%) presented with an asymptomatic murmur, 4 (22.2%) with acute chest pain, 4 (22.2%) with mild heart failure, 2 (11.1%) with severe heart failure, and 2 (11.1%) with cardiogenic shock. Rupture of the right aneurysmal coronary cusp (RCC) made up 15 (83.3%) while those of the non-coronary cusp (NCC) made up the remaining. Most of the RCC ruptures were directed into the right ventricle and all of the NCC ruptures were into the right atrium. Ventricular septal defects (VSDs) were found in 9 (50%) of the patients, (although detected by echocardiography in only one third of those patients), aortic regurgitation in 6 (33.3%) and aortic valve vegetations in 2 (11.1%). Echocardiography was found to be accurate in diagnosing RSOVs with 100% diagnostic accuracy after 1990 with four misdiagnoses before 1990. Of these four patients, two were misdiagnosed as having VSDs, one as having a coronary arteriovenous fistula and one as having a patent ductus arteriosus. The anatomical structure of the "windsock" was seen in 64% of the patients who were correctly diagnosed. The pattern of colour flow and spectral Doppler was seen in all patients and helped to localise the site of rupture and the direction of flow. In summary, echocardiography is a simple and accurate way of diagnosing and defining RSOVs and is the imaging modality of choice. PMID:11874151

Shah, R P; Ding, Z P; Ng, A S; Quek, S S

2001-10-01

202

Relativistic Photon Mediated Shocks  

E-print Network

A system of equations governing the structure of a steady, relativistic radiation dominated shock is derived, starting from the general form of the transfer equation obeyed by the photon distribution function. Closure is obtained by truncating the system of moment equations at some order. The anisotropy of the photon distribution function inside the shock is shown to increase with increasing shock velocity, approaching nearly perfect beaming at upstream Lorentz factors $\\Gamma_{-}>>1$. Solutions of the shock equations are presented for some range of upstream conditions. These solutions are shown to converge as the truncation order is increased.

Amir Levinson; Omer Bromberg

2007-11-21

203

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.

204

Laparoscopic splenectomy for atraumatic splenic rupture.  

PubMed

A traumatic splenic rupture (ASR) is a rare clinical entity. Several underlying benign and malignant conditions have been described as a leading cause. We report on a case of ASR in a 41-year-old man treated with laparoscopic splenectomy. Considering ASR as a life-threatening condition, a prompt diagnosis can be life saving. PMID:21675627

Grossi, Ugo; Crucitti, Antonio; D'Amato, Gerardo; Mazzari, Andrea; Tomaiuolo, Pasquina M C; Cavicchioni, Camillo; Bellantone, Rocco

2011-01-01

205

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. PMID:22263165

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

2011-01-01

206

Star polymers rupture induced by constant forces  

NASA Astrophysics Data System (ADS)

In this work, we study the breakage process of an unknotted three-arm star-shaped polymer when it is pulled from its free ends by a constant force. The star polymer configuration is described through an array of monomers coupled by anharmonic bonds, while the rupture process is tracked in three-dimensional space by means of Langevin Molecular Dynamics simulations. The interaction between monomers is described by a Morse potential, while a Weeks-Chandler-Anderson energetic contribution accounts for the excluded volume interaction. We explore the effect of the molecular architecture on the distributions of rupture times over a broad interval of pulling forces and star configurations. It was found that the rupture time distribution of the individual star arms is strongly affected by the star configuration imposed by the pulling forces and the length of the arms. We also observed that for large pulling forces the rupture time distributions resemble the dominant features observed for linear polymer chains. The model introduced here provides the basic ingredients to describe the effects of tensile forces on stress-induced degradation of branched macromolecules and polymer networks.

García, N. A.; Febbo, M.; Vega, D. A.; Milchev, A.

2014-10-01

207

Penile Fracture with Associated Urethral Rupture  

PubMed Central

Penile fracture of the erect penis is an uncommon but emergent urological trauma. Potential outcomes include erectile dysfunction, penile curvature, and urethral injury. Treatment is emergent surgical repair. We present the case of a 42-year-old man with a penile fracture complicated by a urethral rupture and subsequent repair. A discussion of the key aspects of this condition is presented. PMID:21076536

Boncher, Nicholas A.; Vricella, Gino J.; Jankowski, Jason T.; Ponsky, Lee E.; Cherullo, Edward E.

2010-01-01

208

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

209

Unusual rupture of a flexor profundus tendon.  

PubMed

An unusual rupture of a flexor profundus tendon, previously unreported in the literature, is presented. There was avulsion and proximal displacement of a large bone fragment from the palmar base of the distal phalanx and further retraction of the tendon unattached to the bone fragment. PMID:3958452

Langa, V; Posner, M A

1986-03-01

210

Fault branching and rupture directivity Sonia Fliss  

E-print Network

, some understanding of the mechanics underlying dynamic processes of fault branching and jumping has earthquake from the rupture pattern it left? The answer to that question would be very useful for risk assessment of future earthquakes, even if it is cur- rently unknown if large earthquakes do systematically

Dmowska, Renata

211

Star polymers rupture induced by constant forces.  

PubMed

In this work, we study the breakage process of an unknotted three-arm star-shaped polymer when it is pulled from its free ends by a constant force. The star polymer configuration is described through an array of monomers coupled by anharmonic bonds, while the rupture process is tracked in three-dimensional space by means of Langevin Molecular Dynamics simulations. The interaction between monomers is described by a Morse potential, while a Weeks-Chandler-Anderson energetic contribution accounts for the excluded volume interaction. We explore the effect of the molecular architecture on the distributions of rupture times over a broad interval of pulling forces and star configurations. It was found that the rupture time distribution of the individual star arms is strongly affected by the star configuration imposed by the pulling forces and the length of the arms. We also observed that for large pulling forces the rupture time distributions resemble the dominant features observed for linear polymer chains. The model introduced here provides the basic ingredients to describe the effects of tensile forces on stress-induced degradation of branched macromolecules and polymer networks. PMID:25362341

García, N A; Febbo, M; Vega, D A; Milchev, A

2014-10-28

212

Iatrogenic tracheal rupture in a child: case study and review of literature.  

PubMed

Tracheal rupture is rare in childhood, and optimal treatment is not clear. A 14-year-old boy was admitted to a local hospital after sudden loss of consciousness. He underwent endotracheal intubation and was referred to our hospital. The patient's history revealed that he had voluntarily inhaled butane gas. The physical examination was consistent with coma and cardiogenic shock, and the chest radiograph showed pulmonary edema. The patient was admitted to the intensive care unit, and diuretic and inotropic therapy was started. In the third hour of monitoring of the patient under mechanical ventilation, subcutaneous emphysema and pneumothorax at the right hemithorax were observed without deterioration of the vital functions. Thoracic computed tomography scan findings were consistent with tracheal rupture. The patient was monitored conservatively without surgery. On the fifth day of hospitalization, his tube was removed, and he was discharged on the 12th day with a positive prognosis. In this study, a tracheal rupture case after endotracheal intubation is presented in which the patient recovered completely with conservative therapy. PMID:23925255

Paksu, Muhammet Sukru; Kilinc, Ayse Ayzit; Asilioglu, Nazik; Gunaydin, Mithat; Aydin, Turgay; Guzel, Ahmet

2013-08-01

213

Microscale shock tube  

NASA Astrophysics Data System (ADS)

This project aims at the simulation, design, fabrication and testing of a microscale shock tube. A step by step procedure has been followed to develop the different components of the microscale shock tube and then combine them together to realize the final device. The document reports on the numerical simulation of flows in a microscale shock tube, the experimental study of gas flow in microchannels, the design, microfabrication, and the test of a microscale shock tube. In the first step, a one-dimensional numerical model for simulation of transport effects at small-scale, appeared in low Reynolds number shock tubes is developed. The conservation equations have been integrated in the lateral directions and three-dimensional effects have been introduced as carefully controlled sources of mass, momentum and energy, into the one-dimensional model. The unsteady flow of gas behind the shock wave is reduced to a quasi-steady laminar flow solution, similar to the Blasius solution. The resulting one-dimensional equations are solved numerically and the simulations are performed for previously reported low Reynolds number shock tube experiments. Good agreement between the shock structure simulation and the attenuation due to the boundary layers has been observed. The simulation for predicting the performance of a microscale shock tube shows the large attenuation of shock wave at low pressure ratios. In the next step the steady flow inside microchannels has been experimentally studied. A set of microchannels with different geometries were fabricated. These microchannels have been used to measure the pressure drop as a function of flow rate in a steady compressible flow. The results of the experiments confirm that the flow inside the microscale shock tube follows the laminar model over the experiment's range of Knudsen number. The microscale shock tube is fabricated by deposition and patterning of different thin layers of selected materials on the silicon substrate. The direct sensing piezoelectric sensors were fabricated and integrated with microchannels patterned on the substrate. The channels were then covered with another substrate. This shock tube is 2000 mum long and it has a 2000 mum wide and 17 mum high rectangular cross section equipped with 5 piezoelectric sensors along the tube. The packaged microscale shock tube was installed in an ordinary shock tube and shock waves with different Mach numbers were directed into the channel. A one-dimensional inviscid calculation as well as viscous simulation using the one-dimensional model have also been performed for the above mentioned geometry. The comparison of results with those of the same geometry for an inviscid flow shows the considerable attenuation of shock strength and deceleration of the shock wave for both incident and reflected shock waves in the channel. The comparison of results with numerically generated results with the one-dimensional model presents good agreement for incident shock waves. Keywords. Shock wave, Shock tube, MEMS, Microfluidic, Piezoelectric sensor, Microchannel, Transport phenomena.

Mirshekari, Gholamreza

214

Seismic images of the megathrust rupture during the 25th October 2010 Pagai earthquake, SW Sumatra: Frontal rupture and large tsunami  

NASA Astrophysics Data System (ADS)

The Mentawai segment of the Sumatra subduction zone is locked and likely to produce a large earthquake in the near future. A part of this locked zone ruptured on 12 September 2007 producing twin earthquakes of Mw = 8.5 and 7.9. Recently, a third earthquake of Mw = 7.8 occurred on the 25th October 2010, SW of Pagai Island, Sumatra. The earthquake generated an unexpected very large tsunami on Pagai Islands with run-up height of up to 8 m. Here we present seismic reflection and bathymetry images from the 2010 epicentral region acquired before the earthquake. We find that the frontal thrust is the main active fault in this region and might have ruptured up to the seafloor at 6 km water depth uplifting the water column and producing a large tsunami. Furthermore, finite fault models indicate that this earthquake ruptured the frontal section of the subduction zone, which is generally believed to slip aseismically and be incapable of producing large earthquakes. The presence of aftershocks near the subduction front further confirms that the frontal section of the subduction zone is not aseismic. If the rest of the Mentawai locked zone ruptures the frontal section of the subduction zone during a megathrust, then the resulting tsunami in the Indian Ocean could be devastating.

Singh, Satish C.; Hananto, Nugroho; Mukti, Maruf; Permana, Haryadi; Djajadihardja, Yusuf; Harjono, Heri

2011-08-01

215

Molecular Cloud Formation in Shock-compressed Layers  

Microsoft Academic Search

We investigate the propagation of a shock wave into a warm neutral medium and a cold neutral medium by one-dimensional hydrodynamic calculations with detailed treatment of thermal and chemical processes. Our main result shows that thermal instability inside the shock-compressed layer produces a geometrically thin, dense layer in which a large amount of hydrogen molecules are formed. Linear stability analysis

Hiroshi Koyama; Shu-Ichiro Inutsuka

2000-01-01

216

Strain Measurement Using FBG on COPV in Stress Rupture Test  

NASA Technical Reports Server (NTRS)

White Sands Test Facility (WSTF) was requested to perform ambient temperature hydrostatic pressurization testing of a Space Transportation System (STS) 40-in. Kevlar Composite Overwrapped Pressure Vessel (COPV). The 40-in. vessel was of the same design and approximate age as the STS Main Propulsion System (MPS) and Orbiter Maneuvering System (OMS) vessels. The NASA Engineering Safety Center (NESC) assembled a team of experts and conducted an assessment that involved a review of national Kevlar COPY data. During the review, the STS COPVs were found to be beyond their original certification of ten years. The team observed that the likelihood of STS COPV Stress rupture, a catastrophic burst before leak failure mode, was greater than previously believed. Consequently, a detailed assessment of remaining stress rupture life became necessary. Prior to STS-114, a certification deviation was written for two flights of OV-103 (Discovery) and OV-104 (Atlantis) per rationale that was based on an extensive review of the Lawrence Livermore National Laboratories, COPV data, and revisions to the STS COPV stress levels. In order to obtain flight rationale to extend the certification deviation through the end of the Program, the Orbiter Project Office has directed an interagency COPV team to conduct further testing and analysis to investigate conservatism in the stress rupture model and evaluate material age degradation. Additional analysis of stress rupture life requires understanding the fiber stresses including stress that occurs due to thru-wall composite compression in COPV components. Data must be obtained at both zero gauge pressure (pre-stress) and at the component operating pressure so that this phenomenon can be properly evaluated. The zero gauge pressure stresses are predominantly a result of the autofrettage process used during vessel manufacture. Determining these pre-stresses and the constitutive behavior of the overwrap at pressure will provide necessary information to better predict the remaining life of the STS COPVs. The primary test objective is obtaining data to verify the hypothesis of a radially oriented thru-thickness stress-riser in the COPV composite whose magnitude is a function of the applied pressure and the load history. The anticipated load dependent response follows from the constitutive behavior of the composite overwrap so data to quantify its nonlinear and time dependent response will be sought. The objective of the Fiber Braggs Gratings (FBGs) were to advance the state-of-the-art by developing techniques using FBG sensors that are capable of assessing stress-rupture degradation in Kevlar COPVs in a health monitoring mode (1). Moreover, they sought to answer questions of how embedded sensors affect overall integrity of the structure. And lastly, they sought to provide an important link in the overall stress rupture study that will help close the loop on the COPV fabrication process. NDE inspection methods will be used from start to finish and FBG will be an integral link within the overall chain.

Banks, Curtis; Grant, Joseph

2007-01-01

217

Toxic Shock Syndrome (For Parents)  

MedlinePLUS

... Free Health Lessons Social Media: Connect With Us Toxic Shock Syndrome KidsHealth > Parents > Infections > Bacterial & Viral Infections > ... and Treatment When to Call the Doctor About Toxic Shock Syndrome Toxic shock syndrome (TSS) is a ...

218

Multidimensional effects on relativistic electrons in an oblique shock wave  

SciTech Connect

Multidimensional effects on electron motion in a magnetosonic shock wave propagating obliquely to an external magnetic field are studied by means of a two-dimensional (two space coordinates and three velocities) relativistic, electromagnetic particle code. The simulations demonstrate that after trapping and energization in the main pulse of the shock wave, electrons can be detrapped from it keeping their ultrarelativistic energies. This detrapping is caused by magnetic fluctuations propagating along the wave front. Furthermore, some of the detrapped electrons can be accelerated to much higher energies by the shock wave because they can enter and exit the shock wave as a result of their gyromotions.

Shikii, Kenta; Toida, Mieko [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan)

2010-08-15

219

An explosive shock tube  

Microsoft Academic Search

Experiments with a model explosive shock tube are described. Flow of a ; dense air plasma with speed 25-l0 km\\/sec is obtained by means of an explosive gas ; compressor. Photographs of flow over models were taken when the flow behind the ; shock wave becomes opaque. The experiments were conducted in a laboratory ; explosion chamber, (auth);

A. E. Voitenko; M. A. Lyubimova; E. P. Matochkin

1973-01-01

220

Shock Demagnetization of Pyrrhotite  

NASA Technical Reports Server (NTRS)

Maps of the remanent magnetic field of Mars show demagnetized zones within and around giant impact basins. It is likely that vast regions of the Martian crust were demagnetized due to a shock-induced phase change or magnetic transition of magnetic minerals in the crust. This hypothesis is supported by the fact that around the Hellas and Argyre basins, the edges of the unmagnetized zones roughly correspond with peak shock pressure contour lines of a few GPa. Although pyrrhotite is not a major carrier of magnetization in the Earth s crust, it is a common phase in Martian meteorites and may be an important carrier in the Martian crust. Understanding the effects of shock waves on magnetic minerals is critical for determining the origin of the demagnetized zones in impact basins and possibly for identifying the major magnetic carrier phases. Here we present the results of the first controlled shock demagnetization measurements on pyrrhotite. Previous experiments: Shock demagnetization

Louzada, K. L.; Stewart, S. T.; Weiss, b. P.

2005-01-01

221

On the transition from electromagnetic to electrostatic shocks  

NASA Astrophysics Data System (ADS)

Electrostatic and electromagnetic shocks are relevant in various unmagnetized scenarios. The first can be produced in the laboratory by the interaction of a laser with a near-critical density target and are of interest for the generation of quasi-monoenergetic ion beams, e.g. for cancer therapy, whereas electromagnetic shocks are more relevant in astrophysical scenarios. We explore the conditions under which these shocks are generated in a scenario of two colliding plasma slabs, each consisting of cold ions and electrons with non-zero temperature. The main features of the shock character are discussed as a function of the initial fluid velocity and the electron temperature, and the governing regimes are theoretically predicted, by considering the shock formation time scales and the relevant scales for the instabilities mediating the shock formation. Particle-in-cell simulations confirm the theoretical findings and show the transition between both regimes.

Stockem, Anne; Fiuza, Frederico; Boella, Elisabetta; Fonseca, Ricardo; Silva, Luis

2012-10-01

222

Rupture of the uterus in a primigravida: a case report.  

PubMed

Uterine rupture during a first pregnancy is rare. We present the case of spontaneous intrapartum uterine rupture in a 40 year old primigravida with no prior uterine surgery, and a structurally normal uterus. The patient had obstructed labor. Operative findings were a male fresh stillbirth weighing 3800 g, massive hemoperitoneum, and an anterior transverse rupture at the lower uterine segment. Repair of the rupture was done without bilateral tubal ligation. Although a rare event, the primigravid uterus is not immune to rupture as exemplified by this report. PMID:20499765

Chigbu, B; Onwere, S; Kamanu, C; Aluka, C; Adibe, E; Onichakwe, C

2010-06-01

223

Catheter ablation of canine ventricular myocardium. The use of repetitive short time constant capacitive shocks to increase lesion volume.  

PubMed

Arching and barotrauma, seen with high energy DC catheter ablation, are responsible for diffuse cardiac damage and coronary sinus rupture. In six anesthetized dogs, we investigated the effects of an increasing number of short time-constant capacitive shocks on the volume of myocardial damage. Each dog received capacitive shocks of 2 J/kg at 3 sites in the left ventricle. One shock was delivered in 2 dogs, 2 shocks were delivered in 2 dogs and 3 shocks were delivered in 2 dogs. Shock delivery was not accompanied by hemodynamic collapse, sustained ventricular tachycardia or ventricular fibrillation. The dogs were sacrificed at 60 minutes. Mean (SEM) lesion volumes were 195 (39) mm3, 480 (41) mm3, and 595 (110) mm3, respectively. Despite variability in individual volume of damage, there was a significant increase in lesion volume with an increasing number of shocks. There was no evidence of perforation or tamponade. Increasing myocardial damage can be produced using repetitive capacitive shocks. Delivery of 2 shocks produces clinically useful lesions without the adverse effects associated with single high energy shocks. Repetitive capacitive shocks offer a method of increasing lesion volume without increasing energy and thereby without compromising safety. PMID:9186286

Watanabe, I; Nakai, T; Yanagawa, S; Watanabe, H; Kojima, T; Kondo, K; Takahashi, Y; Saito, S; Ozawa, Y; Kanmatsuse, K

1997-01-01

224

Magnetic Fields In Relativistic Collisionless Shocks  

NASA Astrophysics Data System (ADS)

We present a systematic study on magnetic fields in Gamma-Ray Burst (GRB) relativistic shocks by making use of X-ray and optical afterglow observations, mostly coming from the Swift satellite. We use two methods to constrain the afterglow parameter epsilon_B (the fraction of energy in the magnetic field in the shocked plasma): 1. For the X-ray sample, the observed flux at the end of the X-ray steep decline is larger than or equal to the flux from the external-forward shock. 2. The observed optical afterglow flux arises from the external-forward shock emission. From the method for our X-ray sample (60 GRBs), we determine an upper limit on epsilon_B and from the method for our optical sample (35 GRBs), we determine a measurement for epsilon_B. Combining our X-ray and optical results, the median value we found for epsilon_B is ~ 10^-5. The distributions of epsilon_B from our X-ray and optical samples showed a wide distribution, with epsilon_B ranging from ~ 10^-7 - 10^-3. To characterize how much magnetic field amplification is needed, beyond shock compression of the seed magnetic field, we expressed our results for epsilon_B in terms of an amplification factor, AF. For both our X-ray and optical samples, the median value we found is AF ˜ 50-70. The distributions of AF from our X-ray and optical samples also showed a wide distribution, with AF ranging from ~ 1-1000. These results for epsilon_B and AF suggest that a weak amplification, in addition to shock compression, is needed to explain the afterglow observations. Our main conclusion is that shock compression and weak amplification of the magnetic field in GRB relativistic external shocks is sufficient to explain the afterglow data.

Santana, Rodolfo; Barniol Duran, R.; Kumar, P.

2013-01-01

225

Do World Shocks Drive Domestic Business Cycles? Some Evidence from Structural Estimation  

E-print Network

shocks are the main driving forces of business cycles in small open economies while terms of trade shocks are not. JEL CLASSIFICATION: C32, F41 KEYWORDS: World Shocks, Business Cycles, Small Open Economy Model of business cycles in small open economies. However, the actual empirical evidence is mixed. Estimates

Niebur, Ernst

226

Dynamic rupture on a frictional interface with off-fault damage  

NASA Astrophysics Data System (ADS)

The high stress concentration in the front of dynamic rupture is expected to produce rock damage (reduction of elastic moduli) in the material surrounding the main fault plane. The off-fault yielding of materials and energy absorption in the damage process may reduce the amplitude of near-fault ground motion. However, the local low-velocity zone produced by damage can amplify the motion locally and create a waveguide which will allow the motion to propagate with little geometric attenuation. Moreover, an asymmetric distribution of damage across the fault may produce localized bimaterial interface that could reduce frictional dissipation and increase radiation efficiency. Previous studies incorporated off-fault plastic yielding in simulations of dynamic rupture while keeping the elastic moduli unchanged (Andrews, 1975, 2005; Ben-Zion and Shi, 2005; Templeton et al., 2008). In our model the material around the fault is governed by a brittle damage rheology that accounts for spontaneous evolution of the elastic moduli during off-fault inelastic deformation (e.g., Lyakhovsky et al., 1997; Hamiel et al., 2004). The partitioning of elastic strain energy during rupture propagation among frictional heat, plastic yielding, rock damage (evolution of elastic moduli), and seismic radiation is examined quantitatively to clarify how the damage generation under different conditions influences the maximum ground motion. Off-fault damage is of special importance for ruptures along faults that separate rocks of different elastic properties, because they can generate asymmetric patterns of material degradation that might be observable in the field. Ruptures along frictional faults with and without pre-existing contrasts of elastic properties are studied. Results with the damage model are compared to those obtained with elastic and elasto-plastic models. We especially try to clarify effects associated with feedback between the near-rupture-tip field and the development of damage, such as the possible emergence of a daughter pulse induced by a dynamic bimaterial effect (coseismic asymmetric reduction of elastic moduli).

Xu, S.; Ampuero, J. P.; Ben-Zion, Y.; Lyakhovsky, V.

2009-12-01

227

Detection of supershear rupture in 2013 Craig, Alaska, earthquake  

NASA Astrophysics Data System (ADS)

Seismic ruptures are akin to opening a zipper—a gap in the crust starts in one location and travels along the fault in a particular direction. When a strained fault ruptures in an earthquake, seismic waves also spread out from the epicenter. In some cases, the waves' passage can trigger the initiation of a new rupture ahead of the initial expanding rupture in locked portions of the fault. If the triggered rupture grows successfully, the overall rupture front can then outpace the passage of the shear waves, secondary seismic waves that travel slowly after the earthquake begins and are responsible for the bulk of violent shaking. These earthquakes display what is known as supershear rupture; only seven such earthquakes have previously been recorded.

Schultz, Colin

2014-01-01

228

Retinal detachment associated with traumatic chorioretinal rupture.  

PubMed

Traumatic chorioretinal rupture, also known as sclopetaria, is a full-thickness break of the choroid and retina caused by a high-velocity projectile striking or passing adjacent to, but not penetrating, the globe. Previous reports have emphasized that retinal detachment seldom occurs, and observation alone has been the recommended management strategy. However, the authors present herein a series of consecutive patients with retinal detachment associated with sclopetaria and provide a literature review of the topic. They recommend that patients with traumatic chorioretinal rupture be monitored closely for the development of retinal detachment during the first few weeks after the injury. [Ophthalmic Surg Lasers Imaging Retina. 2014;45:451-455.]. PMID:25153657

Papakostas, Thanos D; Yonekawa, Yoshihiro; Wu, David; Miller, John B; Veldman, Peter B; Chee, Yewlin E; Husain, Deeba; Eliott, Dean

2014-09-01

229

Treatment of Ruptured ICA during Transsphenoidal Surgery  

PubMed Central

Summary Rupture of the internal carotid artery (ICA) during transsphenoidal surgery is a rare but potentially lethal complication. Direct surgical repair of the ICA may be difficult and time-consuming in an acute setting. Urgent endovascular treatments with vascular plug or stent-graft have been the feasible options to date. We desrcibe two cases of iatrogenic rupture of ICA during transsphenoidal surgery. In the first case we occluded the ICA with a vascular plug at the site of tear where cross circulation was adequate. In the second case we had to preserve the ICA with stent-graft since there was no adequate cross circulation. These two strategies are discussed below. PMID:20377977

Ghatge, S.B.; Modi, D.B.

2010-01-01

230

An unusual diagnosis of splenic rupture.  

PubMed

A 22-year-old woman presented with a 3-day history of worsening epigastric pain, non-productive cough and vomiting. On examination she was pale and had abdominal tenderness predominant in the right upper quadrant. Abdominal ultrasound excluded the presence of gall stones, but was unable to rule out free fluid in the abdomen. CT demonstrated extensive high-density ascites; however, no source of bleeding could be demonstrated. Clinically the patient's condition deteriorated, and an exploratory laparotomy was performed. In theatre the splenic capsule was found to have detached from the splenic body and emergency splenectomy was performed. Virology serology later demonstrated acute cytomegalovirus (CMV) infection, although tissue microscopy and CMV staining were negative. No other cause of rupture was found. The interesting aspects of this case include the poor correlation between initial presenting symptoms and subsequent diagnosis, the difficulty encountered in making a firm diagnosis and the atypical cause of rupture. PMID:25293683

Roche, Matthew; Maloku, Fatmir; Abdel-Aziz, Tarek Ezzat

2014-01-01

231

Creep rupture behavior of Stirling engine materials  

NASA Technical Reports Server (NTRS)

The automotive Stirling engine, being investigated jointly by the Department of Energy and NASA Lewis as an alternate to the internal combustion engine, uses high-pressure hydrogen as the working fluid. The long-term effects of hydrogen on the high temperature strength properties of materials is relatively unknown. This is especially true for the newly developed low-cost iron base alloy NASAUT 4G-A1. This iron-base alloy when tested in air has creep-rupture strengths in the directionally solidified condition comparable to the cobalt base alloy HS-31. The equiaxed (investment cast) NASAUT 4G-A1 has superior creep-rupture to the equiaxed iron-base alloy XF-818 both in air and 15 MPa hydrogen.

Titran, R. H.; Scheuerman, C. M.; Stephens, J. R.

1985-01-01

232

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

233

Evaluation of the shock index in dogs presenting as emergencies  

PubMed Central

Objectives To 1) determine the normal range for Shock Index (SI) [defined as heart rate (HR)/systolic blood pressure (SBP)], in healthy dogs, and 2) compare SI in healthy dogs with dogs presenting to the emergency room (ER) deemed to be in or not in a state of shock. Design Prospective study. Animals 68 clinically normal dogs,,18 dogs that were presented to the ER deemed to be in shock and 19 dogs presenting to the ER not deemed to be in shock. Setting University teaching hospital. Interventions Peripheral or central venous blood sampling. Measurements and Main Results Heart rate and SBP were recorded on simulated presentation (healthy dogs), and emergency presentations for both dogs deemed to be in shock and dogs not deemed in shock. Dogs in shock had a median SI of 1.37 (0.87–3.13), which was significantly higher than both other groups; dogs not deemed in shock had median SI 0.73 (0.56–1.20), P<0.0001 and healthy dogs had median SI 0.78 (0.37–1.30) P<0.0001), respectively. Receiver operator characteristic curve analysis suggested a SI cut-off of 1.0, yielding an area under the receiver operator characteristic (AUROC) of 0.89 (Specificity (Sp) 89, Sensitivity (Sn) 90) when comparing dogs deemed in shock with healthy dogs, and 0.92 (Sp 95, Sn 89) when comparing dogs in shock with to dogs not deemed in shock. Conclusions The SI is an easy and non-invasive patient parameter that is higher in dogs that are deemed to be in shock than both healthy dogs and dogs presented as emergencies but not deemed to be in a state of shock. The measurement of SI may have some benefit in clinical assessment of emergency patients. PMID:23855723

Porter, Adam E.; Rozanski, Elizabeth A.; Sharp, Claire R.; Dixon, Kursten L.; Lyn Price, Lori; Shaw, Scott P.

2013-01-01

234

Traumatic dislocation of testes and bladder rupture.  

PubMed

Traumatic dislocation of the testes with bladder rupture occurred in 2 multiply injured patients with pelvic fracture. One had a history of retractile testes and the other of previous testicular dislocation. Surgical correction was performed after closed reduction failed. These injuries must be recognized and treated promptly to maximize the likelihood of testicular salvage. If early intervention is not possible, duplex ultrasonography and pulsed Doppler analysis are the optional valuative studies. PMID:1466102

Lee, J Y; Cass, A S; Streitz, J M

1992-12-01

235

[Corticosteroids in septic shock].  

PubMed

Adequate adrenocortical function is essential to survive critical illness. Most critically ill patients display an elevated plasma Cortisol level, reflecting activation of the pituitary-adrenal axis, which is considered to be a homeostatic adaptation. In the setting of critical illness, the failure of an appropriate neuroendocrine response can lead to the picture of vasopressor-dependent refractory hypotension. In randomised trials with patients in septic shock, a more rapid haemodynamic recovery was obtained with physiological doses of hydrocortisone than with placebo. The observed haemodynamic response following hydrocortisone administration supports the concept of relative adrenal insufficiency. Causes of this relative adrenal insufficiency are a dysfunction of the hypothalamic-pituitary-adrenal axis and/or Cortisol resistance. There is increasing evidence that Cortisol physiology and regulation are substantially altered in the course of septic shock. Several controlled studies have shown that stress doses of hydrocortisone given in patients with septic shock reduce the time to shock reversal and decrease mortality. A multicenter large-scale trial (CORTICUS) is on the way investigating the benefit of stress doses of hydrocortisone on the mortality of septic shock. In this review glucocorticoid physiology and regulation during septic shock and the effects of hydrocortison administration in the course of septic shock are being discussed. PMID:12506678

Clodi, M

2002-01-01

236

Ruptured Corpus Luteal Cyst: CT Findings  

PubMed Central

Objective To evaluate the CT findings of ruptured corpus luteal cysts. Materials and Methods Six patients with a surgically proven ruptured corpus luteal cyst were included in this series. The prospective CT findings were retrospectively analyzed in terms of the size and shape of the cyst, the thickness and enhancement pattern of its wall, the attenuation of its contents, and peritoneal fluid. Results The mean diameter of the cysts was 2.8 (range, 1.5-4.8) cm; three were round and three were oval. The mean thickness of the cyst wall was 4.7 (range, 1-10) mm; in all six cases it showed strong enhancement, and in three was discontinuous. In five of six cases, the cystic contents showed high attenuation. Peritoneal fluid was present in all cases, and its attenuation was higher, especially around the uterus and adnexa, than that of urine present in the bladder. Conclusion In a woman in whom CT reveals the presence of an ovarian cyst with an enhancing rim and highly attenuated contents, as well as highly attenuated peritoneal fluid, a ruptured corpus luteal cyst should be suspected. Other possible evidence of this is focal interruption of the cyst wall and the presence of peritoneal fluid around the adnexa. PMID:12679633

Choi, Hyuck Jae; Kim, Sun Ho; Kim, Hyo-Cheol; Park, Chang Min; Lee, Hak Jong; Moon, Min Hoan; Jeong, Jun Yong

2003-01-01

237

Single Event Gate Rupture in EMCCD technology  

NASA Astrophysics Data System (ADS)

The high electric fields (typically 3 MV/cm2 interpoly field) utilised in Electron Multiplying Charged Coupled Devices (EMCCDs) reveal a potential vulnerability from Single Event Phenomena (SEP), in particular Single Event Gate Rupture (SEGR). SEGR is where a conduction path between two conductive areas of the CCD is produced, causing device failure. If EMCCDs are to be used for space applications the susceptibility to these events needs to be explored. A positive result from such an investigation can increase the technology readiness level of the device moving it another step closer to being used in space. Testing undertaken at the CYClotron of LOuvain la NEuve (CYCLONE), using the Heavy Ion Facility (HIF), conclusively showed EMCCD technology to have resilience to heavy ions that surpassed initial expectations. The simulations undertaken prior to experiment suggested gate rupture would occur at 20-40 MeV cm2/mg, however Linear Energy Transfers (LETs) greater than 100 MeV cm2/mg proved to not cause a rupture event. Within the radiation belts heavy ions with an LET greater than 60 MeV cm2/mg are not very common when compared to the fluxes used at the HIF. Possible reasons for this result are discussed in this work, leading to a conclusion that EMCCD technology is a secure choice for space flight.

Evagora, A. M.; Murray, N. J.; Holland, A. D.; Burt, D.

2012-12-01

238

Biosensing using rupture event scanning (REVS)™  

NASA Astrophysics Data System (ADS)

We have developed a sensitive and economical method to detect analytes directly. The technique, which we term rupture event scanning (REVS™), is based on rapidly oscillating an acoustic wave device on which the analytes have been captured. As the magnitude of oscillation of the surface of the acoustic wave device is increased, there is increasing acceleration of adherent analytes. This in turn results in a larger force exerted by the surface on the particle, that ultimately causes rupture of the bonds attaching the particle to the surface. Using the same device, we can very sensitively monitor the excitation of vibrations in the acoustic wave device produced by bond rupture, which are then converted into an electrical signal. The signal indicates not only the presence of specifically bound analytes and their affinity for the receptor, but also the number of analytes present. The method works in air, water and complex biological fluids, is quantitative over at least six orders of magnitude of particle titre, and in affinity from sub-mM to pM. For selected analyte-receptor systems the sensitivity can be as low as 80 fg mm-2 (8 × 10-14 g mm-2). In this paper an example application of REVS™ is presented and the physical forces involved in the process are discussed.

Cooper, Matthew A.

2003-11-01

239

Operative intra-aortic balloon rupture.  

PubMed

Rupture of an intra-aortic balloon (IAB), inserted to assist in weaning from cardiopulmonary bypass, occurred during attempted intra-aortic administration of protamine in a 71-year-old male who later died. Intra-aortic balloon counterpulsation (IABC) is most commonly utilized to assist in weaning from cardiopulmonary bypass (CPB) or to augment low-flow states following CPB. In-hospital survival following IAB insertion in these circumstances in patients with coronary artery disease is approximately 60 per cent. Patients with valvular disease have a lower in-hospital survival rate (50 per cent). Complications of IABC are usually of vascular or infectious origin. Balloon rupture is a rare though potentially lethal complication. The effects of balloon rupture may be compounded by the use of helium as a driving gas to inflate the balloon. Intra-aortic administration of protamine has not been shown to be superior to peripheral administration and should be avoided if an IAB is in place. PMID:3383321

Finegan, B A; Comm, D G

1988-05-01

240

Surface Rupture Connecting Deep-Seated Landslides of the Mw6.9 14 June 2008 Iwate- Miyagi Nairiku, NE Japan, Earthquake  

NASA Astrophysics Data System (ADS)

The Mw 6.9 Iwate-Miyagi Nairiku earthquake hit mountain regions in northern Honshu Island, and was accompanied by ~20 km of a NNW trending surface rupture and by a lot of landslides. Morphological features show that the surface ruptures are mainly thrust faulting which is consistent with the focal mechanism of the mainshock under the WNW-ESE compressional stress field in northern Honshu. Amounts of vertical offset and horizontal shortening are mostly smaller than 50 cm (~ 1m of net slip) (See details in Toda et al., 2008, in this volume). Some of the surface ruptures neighbored deep-seated landslides. Meanwhile, near the southern end of the rupture zone, we found N-E-striking surface rupture with exceptionally large offset connecting two massive deep-seated landslides with volumes more than 100,000 m3. The backscarps are more than 100 m high, as high as the differences in elevation of the ridges this rupture cut, implying the landslides been triggered by faulting rather than shaking. Airborne and ground-based LiDAR measurements together with our field observations reveal typical features of strike-slip faulting such as mole tracks, fissures, pressure ridges, bulges, and shutter ridges as well as the offset rills and ridges (See details in Maruyama et al., 2008, in this volume). The rupture consists of a E-W- striking ~1-km-long continuous rupture involved with 4-to-7-m dextral and 2-to-4-m vertical offsets of a paved road, trails, and rills, a N-S-striking W-side-up 0.2-km-long thrust rupture forked off at the center of the E-W- striking rupture, a NE-SW-striking NW-side-up 0.15-km-long dextral pressure ridge branched off at eastern E- W-striking scarp, and NW-SE-trending 0.1-km-long cracks branched out toward north at the center of the E- W-striking rupture. Another NW-SE-striking cracks extend to a backscarp at the eastern termination of the E- W-striking rupture. This detail mapping of the ruptures provides that this strike-slip dominant fault plays a role of a lateral ramp connecting two distinct NNE-trending thrust faults, and that NW-SE-trending cracks adjust displacement field. Since the backscarps trend NW-SE at the both termination of the surface rupture, it implies that NW-SE- striking tension cracks might have been formed at the both terminations of the rupture and triggered the giant landslides.

Yoshimi, M.; Maruyama, T.; Toda, S.

2008-12-01

241

Imploding conical shock waves  

NASA Astrophysics Data System (ADS)

The behaviour of conical shock waves imploding axisymmetrically was first studied numerically by Hornung (J Fluid Mech 409:1-12, 2000) and this prompted a limited experimental investigation into these complex flow patterns by Skews et al. (Shock Waves 11:323-326, 2002). Modification of the simulation boundary conditions, resulting in the loss of self-similarity, was necessary to image the flow experimentally. The current tests examine the temporal evolution of these flows utilising a converging conical gap of fixed width fed by a shock wave impinging at its entrance, supported by CFD simulations. The effects of gap thickness, angle and incident shock strength were investigated. The wave initially diffracts around the outer lip of the gap shedding a vortex which, for strong incident shock cases, can contain embedded shocks. The converging shock at exit reflects on the axis of symmetry with the reflected wave propagating outwards resulting in a triple point developing on the incident wave together with the associated shear layer. This axisymmetric shear layer rolls up into a mushroom-shaped toroidal vortex ring and forward-facing jet. For strong shocks, this deforms the Mach disk to the extent of forming a second triple point with the primary shock exhibiting a double bulge. Separate features resembling the Richtmeyer-Meshkov and Kelvin-Helmholtz instabilities were noted in some tests. Aside from the incident wave curvature, the reflection patterns demonstrated correspond well with the V- and DV-types identified by Hornung although type S was not clearly seen, possibly due to the occlusion of the reflection region by the outer diffraction vortex at these early times. Some additional computational work explicitly exploring the limits of the parameter space for such systems has demonstrated the existence of a possible further reflection type, called vN-type, which is similar to the von Neumann reflection for plane waves. It is recommended that the parameter space be more thoroughly explored experimentally.

Paton, R. T.; Skews, B. W.; Rubidge, S.; Snow, J.

2013-07-01

242

Liver Hydatid Cyst with Transdiaphragmatic Rupture and Lung Hydatid Cyst Ruptured into Bronchi and Pleural Space  

SciTech Connect

The aim of this case study is to present effectiveness of percutaneous drainage as a treatment option of ruptured lung and liver hydatid cysts. A 65-year-old male patient was admitted with complicated liver and lung hydatid cysts. A liver hydatid cyst had ruptured transdiaphragmatically, and a lung hydatid cyst had ruptured both into bronchi and pleural space. The patient could not undergo surgery because of decreased respiratory function. Both cysts were drained percutaneously using oral albendazole. Povidone-iodine was used to treat the liver cyst after closure of the diaphragmatic rupture. The drainage was considered successful, and the patient had no recurrence of signs and symptoms. Clinical, laboratory, and radiologic recovery was observed during 2.5 months of catheterization. The patient was asymptomatic after catheter drainage. No recurrence was detected during 86 months of follow-up. For inoperable patients with ruptured liver and lung hydatid cysts, percutaneous drainage with oral albendazole is an alternative treatment option to surgery. The percutaneous approach can be life-saving in such cases.

Ar Latin-Small-Letter-Dotless-I bas, Bilgin Kadri, E-mail: bilginaribas@hotmail.com; Dingil, Guerbuez [A.Y. Ankara Oncology Training and Research Hospital, Department of Radiology (Turkey); Koeroglu, Mert [Sueleyman Demirel University School of Medicine, Department of Radiology (Turkey); Uenguel, Uemit; Zaral Latin-Small-Letter-Dotless-I , Aliye Ceylan [A.Y. Ankara Oncology Training and Research Hospital, Department of Radiology (Turkey)

2011-02-15

243

A cylindrical converging shock tube for shock-interface studies.  

PubMed

A shock tube facility for generating a cylindrical converging shock wave is developed in this work. Based on the shock dynamics theory, a specific wall profile is designed for the test section of the shock tube to transfer a planar shock into a cylindrical one. The shock front in the converging part obtained from experiment presents a perfect circular shape, which proves the feasibility and reliability of the method. The time variations of the shock strength obtained from numerical simulation, experiment, and theoretical estimation show the desired converging effect in the shock tube test section. Particular emphasis is then placed on the problem of shock-interface interaction induced by cylindrical converging shock waves. For this purpose, membrane-less gas cylinder is adopted to form the interface between two different fluids while the laser sheet technique to visualize the flow field. The result shows that it is convenient to perform such experiments in this facility. PMID:24517812

Luo, Xisheng; Si, Ting; Yang, Jiming; Zhai, Zhigang

2014-01-01

244

A cylindrical converging shock tube for shock-interface studies  

NASA Astrophysics Data System (ADS)

A shock tube facility for generating a cylindrical converging shock wave is developed in this work. Based on the shock dynamics theory, a specific wall profile is designed for the test section of the shock tube to transfer a planar shock into a cylindrical one. The shock front in the converging part obtained from experiment presents a perfect circular shape, which proves the feasibility and reliability of the method. The time variations of the shock strength obtained from numerical simulation, experiment, and theoretical estimation show the desired converging effect in the shock tube test section. Particular emphasis is then placed on the problem of shock-interface interaction induced by cylindrical converging shock waves. For this purpose, membrane-less gas cylinder is adopted to form the interface between two different fluids while the laser sheet technique to visualize the flow field. The result shows that it is convenient to perform such experiments in this facility.

Luo, Xisheng; Si, Ting; Yang, Jiming; Zhai, Zhigang

2014-01-01

245

Comparison between Amnisure Placental Alpha Microglobulin-1 Rapid Immunoassay and Standard Diagnostic Methods for Detection of Rupture of Membranes  

PubMed Central

Objective. To determine the diagnostic accuracy of placental alpha microglobulin-1 assay and standard diagnostic methods for detecting rupture of membrane. Study Design. Prospective diagnostic study, between June 2011 to November 2011 at a tertiary centre. Initial evaluation included both the standard diagnostic methods for rupture of membranes and placental alpha microglobulin-1 immunoassay. The actual rupture of membranes was diagnosed on review of the medical records after delivery (absence of membrane or a positive pad chart). Main Outcome Measures. Placental alpha microglobulin-1 immunoassay and standard diagnostic methods for diagnosis of rupture of membrane. Results. A total of 211 patients were recruited. At initial presentation, 187 patients (88.6%) had ruptured membranes, while 24 patients (11.4%) had intact membranes. Placental alpha microglobulin-1 immunoassay confirmed rupture of membranes at initial presentation with a sensitivity of 95.7% (179 of 187), specificity of 100% (24 of 24), positive predictive value of 100% (179 of 179), and negative predictive value of 75.0% (24 of 32). By comparison, the conventional standard diagnostic methods had a sensitivity of 78.1% (146 of 187), specificity of 100% (24 of 24), positive predictive value of 100% (146 of 146), and negative predictive value of 36.9% (24 of 65) in diagnosing rupture of membrane. Conclusion. Placental alpha-microglobulin-1 immunoassay is a rapid and accurate method for confirming the diagnosis of rupture of membrane. It was superior to conventional standard diagnostic methods (pooling, nitrazine, and ferning), the nitrazine test alone or fern test alone. PMID:24073412

Ng, Beng Kwang; Lim, Pei Shan; Shafiee, Mohamad Nasir; Abdul Ghani, Nur Azurah; Mohamed Ismail, Nor Azlin; Omar, Mohd Hashim; Muhammad Yassin, Muhammad Abdul Jamil

2013-01-01

246

The susitna glacier thrust fault: Characteristics of surface ruptures on the fault that initiated the 2002 denali fault earthquake  

USGS Publications Warehouse

The 3 November 2002 Mw 7.9 Denali fault earthquake sequence initiated on the newly discovered Susitna Glacier thrust fault and caused 48 km of surface rupture. Rupture of the Susitna Glacier fault generated scarps on ice of the Susitna and West Fork glaciers and on tundra and surficial deposits along the southern front of the central Alaska Range. Based on detailed mapping, 27 topographic profiles, and field observations, we document the characteristics and slip distribution of the 2002 ruptures and describe evidence of pre-2002 ruptures on the fault. The 2002 surface faulting produced structures that range from simple folds on a single trace to complex thrust-fault ruptures and pressure ridges on multiple, sinuous strands. The deformation zone is locally more than 1 km wide. We measured a maximum vertical displacement of 5.4 m on the south-directed main thrust. North-directed backthrusts have more than 4 m of surface offset. We measured a well-constrained near-surface fault dip of about 19?? at one site, which is considerably less than seismologically determined values of 35??-48??. Surface-rupture data yield an estimated magnitude of Mw 7.3 for the fault, which is similar to the seismological value of Mw 7.2. Comparison of field and seismological data suggest that the Susitna Glacier fault is part of a large positive flower structure associated with northwest-directed transpressive deformation on the Denali fault. Prehistoric scarps are evidence of previous rupture of the Sustina Glacier fault, but additional work is needed to determine if past failures of the Susitna Glacier fault have consistently induced rupture of the Denali fault.

Crone, A. J.; Personius, S. F.; Craw, P. A.; Haeussler, P. J.; Staft, L. A.

2004-01-01

247

Preventing Electrical Shock  

E-print Network

that current levels greater than 8 milliamperes are unsafe. This is only a fraction of the current needed to power a 60-watt light bulb, which draws about 500 milliamperes. Interestingly, animals are more sensitive to low inten- sity electrical currents than...09501 Preventing Electrical Shock Effect of electric current on humans. Milliampere Effects SAFE Less than 1 No sensation, not felt. 1 to 8 Shock sensation; not painful; can let go at will. UNSAFE 8 to 15 Painful shock; can let go at will. 15 to 20...

Smith, David

2004-09-16

248

Structure-Function Analysis of the Heat Shock Factor-binding Protein Reveals a Protein Composed Solely of a Highly  

E-print Network

- main of heat shock factor (HSF) 1 as the bait. Similar in size to HSF1 trimerization domain, human HSBP transcription (5), and the heat shock transcription factor 1 (HSF1)1 oligomeriz- ing temporally upon stress

Morimoto, Richard

249

Studies of shock focusing and nonlinear resonance in shock tubes  

NASA Technical Reports Server (NTRS)

Some current problems in noise pollution which involve the dynamics of weak shock waves can be succesfully investigated using shock tubes and shock-tube techniques. Two examples presently under study are discussed; in one case the experiments are carried out in a large, conventional shock tube originally designed for studies of rarefied gasdynamics, while in the other case the experimental facility is a less conventional 'repeating' shock tube.

Sturtevant, B.

1973-01-01

250

Rupture mechanism and source parameters of Umbria-Marche mainshocks from strong motion data  

NASA Astrophysics Data System (ADS)

A long sequence of earthquakes causing few casualties and considerable damage in a wide zone struck Central Italy starting on September 26, 1997. Theearthquakes are characterized by normal faulting mechanism, with a NE-SW(anti-Apenninic direction) tension axis. In this paper we analyze the accelerometric recordings collected by the accelerograph stations belonging to the National Accelerograph Network. About 10 stations were triggered by the mainshocks of the sequence. In particular, a small size foreshock and the two mainshocks that occurred on September,26 (00:33(GMT) MW = 5.7 and 09:40 MW = 6.0) have been recorded by two digital 3-C accelerometers located at near source distances (within 30 km from the faults). These records are relevant to investigate the detail of therupture kinematics, due to the close epicentral distance and azimuthallocation relative to the fault orientation and geometry. Using a trial and error approach we modeled the source mechanism through the fit of the arrival times, the apparent source time duration, the main polarization features and the entire waveforms of the recorded signals, in order to get some insight on the rupture evolution, the location of the fracture origin point and the fault geometry. Based on this fault kinematic model, inferences on fault slip distribution are obtained by modeling the S acceleration waveform, comparing the ray theory synthetics with 1-5 Hz band filtered ground velocity records.The final model shows that the seismic ruptures occurred along two adjacent,sub-parallel, low angle dipping normal faults. Ruptures bothnucleated from the fault bottom and propagated up-dip, showing differentrupture velocity and length. The presence of a transfer zone (barrier)can be suggested by the mainshocks rupture evolution. This transfer zonehas probably controlled the amplitude increase of local stressreleased by the first rupture at its NW edge which triggered about 9 hourslater the second rupture. The inferred model was used to compute the predictedground acceleration in the near source range, using a hybridstatistical-deterministic approach.A similar trial and error method has been also applied to the October 14, 199715:23 earthquake (MW = 5.6). The inferred kinematic model indicates a rupture nucleating from the faultbottom and propagating up-dip, toward the SE direction. Thus the three mainshocks ruptured distinct fault segments, adjacent and slightly offsetfrom one to another.

Capuano, P.; Zollo, A.; Emolo, A.; et al.

251

Chondrule Formation in Radiative Shock  

Microsoft Academic Search

Previous models of solid grain melting in solar nebula shocks have neglected gas cooling behind the shock front, i.e., they considered adiabatic shocks. The effect of gas cooling in the postshock region is studied. It was found that shocked gas is cooled efficiently by dipole molecules and small dust particles, and this results in a sharp increase in gas density

T. V. Ruzmaikina; W. H. Ip

1994-01-01

252

Comparative yield estimation via shock hydrodynamic methods  

SciTech Connect

Shock TOA (CORRTEX) from recent underground nuclear explosions in saturated tuff were used to estimate yield via the simulated explosion-scaling method. The sensitivity of the derived yield to uncertainties in the measured shock Hugoniot, release adiabats, and gas porosity is the main focus of this paper. In this method for determining yield, we assume a point-source explosion in an infinite homogeneous material. The rock is formulated using laboratory experiments on core samples, taken prior to the explosion. Results show that increasing gas porosity from 0% to 2% causes a 15% increase in yield per ms/kt{sup 1/3}. 6 refs., 4 figs.

Attia, A.V.; Moran, B.; Glenn, L.A.

1991-06-01

253

Nonlinearly stable compact schemes for shock calculations  

NASA Technical Reports Server (NTRS)

The applications of high-order, compact finite difference methods in shock calculations are discussed. The main concern is to define a local mean which will serve as a reference for introducing a local nonlinear limiting to control spurious numerical oscillations while maintaining the formal accuracy of the scheme. For scalar conservation laws, the resulting schemes can be proven total-variation stable in one space dimension and maximum-norm stable in multiple space dimensions. Numerical examples are shown to verify accuracy and stability of such schemes for problems containing shocks. These ideas can also be applied to other implicit schemes such as the continuous Galerkin finite element methods.

Cockburn, Bernardo; Shu, Chi-Wang

1992-01-01

254

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

255

Shock wave reflection phenomena  

NASA Astrophysics Data System (ADS)

The present publication encompasses shock-wave reflection phenomena in a review of their phenomenological aspects in a range of flow types. Oblique shock-wave reflections are analyzed by means of expressions from the two- and three-shock theories with illustrations of the transition boundaries from regular and Mach reflection. Shock-wave reflection is further reviewed for such cases as unsteady, steady, and pseudosteady flows with criteria for the formation and termination of these reflection cases. Experimental results are compared to analytical predictions, and the governing equations are treated with additional expressions and modifications that describe viscous and real gas effects. It is expected that the work in this volume can lead to the development of numerical codes for the prediction of regular reflection as well as single- and double-Mach reflection.

Ben-Dor, Gabi

256

Life Shocks and Homelessness  

PubMed Central

We exploited an exogenous health shock—namely, the birth of a child with a severe health condition—to investigate the effect of a life shock on homelessness in large cities in the United States as well as the interactive effects of the shock with housing market characteristics. We considered a traditional measure of homelessness, two measures of housing instability thought to be precursors to homelessness, and a combined measure that approximates the broadened conceptualization of homelessness under the 2009 Homeless Emergency Assistance and Rapid Transition to Housing Act (2010). We found that the shock substantially increases the likelihood of family homelessness, particularly in cities with high housing costs. The findings are consistent with the economic theory of homelessness, which posits that homelessness results from a conjunction of adverse circumstances in which housing markets and individual characteristics collide. PMID:23868747

Corman, Hope; Noonan, Kelly; Reichman, Nancy E.

2014-01-01

257

Toxic shock syndrome  

MedlinePLUS

... by a toxin produced by certain types of Staphylococcus bacteria. A similar syndrome, called toxic shock-like ... men. Risk factors include: Recently having a baby Staphylococcus aureus ( S. aureus ) infection, commonly called a Staph infection ...

258

Shock Tube Design  

E-print Network

Shock accelerated flows exhibit some of the most violent and complex mechanisms in nature by which two separate fluids can be mixed. The Richtmyer-Meshkov instability (RMI) is generated when a perturbed interface between two fluids is impulsively...

Koppenberger, Peter K.

2010-07-14

259

Life shocks and homelessness.  

PubMed

We exploited an exogenous health shock-namely, the birth of a child with a severe health condition-to investigate the effect of a life shock on homelessness in large cities in the United States as well as the interactive effects of the shock with housing market characteristics. We considered a traditional measure of homelessness, two measures of housing instability thought to be precursors to homelessness, and a combined measure that approximates the broadened conceptualization of homelessness under the 2009 Homeless Emergency Assistance and Rapid Transition to Housing Act (2010). We found that the shock substantially increases the likelihood of family homelessness, particularly in cities with high housing costs. The findings are consistent with the economic theory of homelessness, which posits that homelessness results from a conjunction of adverse circumstances in which housing markets and individual characteristics collide. PMID:23868747

Curtis, Marah A; Corman, Hope; Noonan, Kelly; Reichman, Nancy E

2013-12-01

260

Main University Entrance Main University Reception  

E-print Network

Economics Research Group School of Arts (taught programmes) Marie Jahoda School of Social Sciences (UG, PG Athletics Centre Eastern Gateway Main Reception Beldam Gallery Brunel Business School Lancaster Suite Conference Office Mary Seacole Health and Social Care (enquiries) Sports Centre St Johns Information Systems

Martin, Ralph R.

261

Primary surface ruptures of the great Himalayan earthquakes in 1934 and 1255  

NASA Astrophysics Data System (ADS)

It is unclear where plate boundary thrusts generate giant rather than great earthquakes. Along the Himalayas, the source sizes and recurrence times of large seismic events are particularly uncertain, since no surface signatures were found for those that shook the range in the twentieth century. Here we challenge the consensus that these events remained blind and did not rupture the surface. We use geomorphological mapping of fluvial deposits, palaeo-seismological logging of river-cut cliffs and trench walls, and modelling of calibrated 14C ages, to show that the Mw 8.2 Bihar-Nepal earthquake on 15 January 1934 did break the surface: traces of the rupture are clear along at least 150km of the Main Frontal Thrust fault in Nepal, between 85°50' and 87°20'E. Furthermore, we date collapse wedges in the Sir Valley and find that the 7 June AD 1255 earthquake, an event that devastated Kathmandu and mortally wounded the Nepalese King Abhaya Malla, also ruptured the surface along this stretch of the mega-thrust. Thus, in the past 1,000 years, two great earthquakes, 679 years apart, rather than one giant eleventh-century AD event, contributed to the frontal uplift of young river terraces in eastern Nepal. The rare surface expression of these earthquakes implies that surface ruptures of other reputedly blind great Himalayan events might exist.

Sapkota, S. N.; Bollinger, L.; Klinger, Y.; Tapponnier, P.; Gaudemer, Y.; Tiwari, D.

2013-01-01

262

Uniform Shock Waves in Disordered Granular Matter  

E-print Network

The confining pressure $P$ is perhaps the most important parameter controlling the properties of granular matter. Strongly compressed granular media are, in many respects, simple solids in which elastic perturbations travel as ordinary phonons. However, the speed of sound in granular aggregates continuously decreases as the confining pressure decreases, completely vanishing at the jamming-unjamming transition. This anomalous behavior suggests that the transport of energy at low pressures should not be dominated by phonons. In this work we use simulations and theory to show how the response of granular systems becomes increasingly nonlinear as pressure decreases. In the low pressure regime the elastic energy is found to be mainly transported through nonlinear waves and shocks. We numerically characterize the propagation speed, shape, and stability of these shocks, and model the dependence of the shock speed on pressure and impact intensity by a simple analytical approach.

L. R. Gomez; A. M. Turner; V. Vitelli

2012-08-01

263

Wall shocks in high-energy-density shock tube experiments  

SciTech Connect

The radiative precursor of a sufficiently fast shock has been observed to drive the vaporization of shock tube material ahead of the shock. The resulting expansion drives a converging blast wave into the gas volume of the tube. The effects of this wall shock may be observed and correlated with primary shock parameters. We demonstrate this process in experiments performed on the Omega Laser Facility, launching shocks propagating through xenon with speeds above 100 km/s driven by ablation pressures of approximately 50 Mbars. Wall shocks in laser experiments, in which the principal shock waves themselves should not be radiative, are also reported--in which the wall shocks have been launched by some other early energy source.

Doss, F. W.; Drake, R. P.; Kuranz, C. C. [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Michigan 48109-2143 (United States); Robey, H. F. [Lawrence Livermore National Laboratory, Livermore, California 94551-0808 (United States)

2009-11-15

264

Dynamics of three-dimensional thin film rupture  

NASA Astrophysics Data System (ADS)

We consider the problem of thin film rupture driven by van der Waals forces. A fourth-order nonlinear PDE governs the low Reynolds number lubrication model for a viscous liquid on a solid substrate. Finite-time singularities in this equation model rupture leading to formation of dry spots in the film. Our study addresses the problem of rupture in the full three-dimensional geometry. We focus on stability and selection of the dynamics determined by the initial conditions on small finite domains with planar and axisymmetric geometries. We also address the final stages of the dynamics - self-similar dynamics for point, line, and ring rupture. We will demonstrate that line and ring rupture are unstable and will generically destabilize to produce axisymmetric rupture at isolated points.

Witelski, Thomas P.; Bernoff, Andrew J.

2000-12-01

265

Shock/shock interference on a transpiration cooled hemispherical model  

NASA Technical Reports Server (NTRS)

Experimental results are presented which show the effectiveness of transpiration cooling in reducing the peak heat flux caused by an impinging shock on a bow shock of a hemispherical model. The 12-inch diameter hemispherical transpiration model with helium coolant was tested in the Calspan 48-inch Hypersonic Shock Tunnel at nominal Mach 12.1 and freestream unit Reynolds number of 0.33 x 10 to the 6th/ft. An incident shock wave, generated by a blunt flat-plate shock generator inclined at 10 deg to the freestream, intersected the bow shock of the model to produce shock/shock interference. The stagnation heat flux without coolant or shock/shock interference was about 1.6 times a smooth surface laminar prediction due to effective roughness of the coolant ejection slots. A coolant mass flux 31 percent of the freestream mass flux reduced the stagnation heat flux to zero without shock/shock interference. However, for the same coolant mass flux and with shock/shock interference the peak heat flux was only reduced 8.3 percent, even though the total integrated heat load was reduced.

Nowak, Robert J.; Wieting, Allan R.; Holden, Michael S.

1990-01-01

266

Simplified approach for design of raft foundations against fault rupture. Part I: free-field  

Microsoft Academic Search

Over the past few decades, earthquake engineering research mainly focused on the effects of strong seismic shaking. After\\u000a the 1999 earthquakes in Turkey and Taiwan, and thanks to numerous cases where fault rupture caused substantial damage to structures,\\u000a the importance of faulting-induced deformation has re-emerged. This paper, along with its companion (Part II), exploits parametric\\u000a results of finite element analyses

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

2008-01-01

267

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

268

Successful infarct exclusion for postinfarction left ventricular free wall rupture  

PubMed Central

The mortality of postinfarction left ventricular free wall rupture is still high. Several surgical techniques have been used for repairing such ruptures. Here, we describe using an infarction exclusion technique to successfully treat a case of a blow-out type postinfarction left ventricular free wall rupture. This technique has frequently been used for repairing postinfarction ventricular septal perforation. In this case, infarcted myocardial tearing was prevented, and complete haemostasis was achieved by infarct exclusion. PMID:23424241

Kato, Yasuyuki; Fukui, Toshihiro; Tabata, Minoru; Takanashi, Shuichiro

2013-01-01

269

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

270

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

271

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

272

Rapid control in ruptured abdominal aneurysms.  

PubMed

Rapid control of a ruptured abdominal aneurysm can be achieved under local anesthesia by passing a Fogarty catheter, 8/22 F, retrograde from either femoral artery up into the thoracic aorta and inflating the balloon after administering heparin to the patient. This method avoids the often fatal hypotension that may occur with induction of general anesthesia in the hypovolemic patient. In cases in which the Fogarty catheter cannot pass up the iliac artery, direct insertion of the catheter through the aneurysm can be used, but this method requires the induction of general anesthesia prior to aortic control. PMID:7259508

Sensenig, D M

1981-08-01

273

Atherosclerotic plaque rupture and thrombosis. Evolving concepts.  

PubMed

Rupture of an atherosclerotic plaque associated with partial or complete thrombotic vessel occlusion is fundamental to the development of ischemic coronary syndromes. Plaques that produce only mild-to-moderate angiographic luminal stenosis are frequently those that undergo abrupt disruption, leading to unstable angina or acute myocardial infarction. Plaques with increased lipid content appear more prone to rupture, particularly when the lipid pool is localized eccentrically within the intima. Macrophages appear to play an important role in atherogenesis, perhaps by participating in the uptake and metabolism of lipoproteins, secretion of growth factors, and production of enzymes and toxic metabolites that may facilitate plaque rupture. In addition, the particular composition or configuration of a plaque and the hemodynamic forces to which it is exposed may determine its susceptibility to disruption. Exposure of collagen, lipids, and smooth muscle cells after plaque rupture leads to the activation of platelets and the coagulation cascade system. The resulting thrombus may lead to marked reduction in myocardial perfusion and the development of an unstable coronary syndrome, or it may become organized and incorporated into the diseased vessel, thus contributing to the progression of atherosclerosis. In unstable angina, plaque disruption leads to thrombosis, which is usually labile and results in only a transient reduction in myocardial perfusion. Release of vasoactive substances, arterial spasm, or increases in myocardial oxygen demand may contribute to ischemia. In acute myocardial infarction, plaque disruption results in a more persistent thrombotic vessel occlusion; the extent of necrosis depends on the size of the artery, the duration of occlusion, the presence of collateral flow, and the integrity of the fibrinolytic system. Thrombi that undergo lysis expose a highly thrombogenic surface to the circulating blood, which has the capacity of activating platelets and the coagulation cascade system and may lead to thrombotic reocclusion. Measurements aimed at reversing the process of atherosclerosis via cholesterol reduction and enhanced high density lipoprotein activity are encouraging. Active research is being focused on the development of new antithrombotic tools, such as inhibitors of thrombin, thromboxane, and serotonin receptor antagonists, and monoclonal antibodies aimed at blocking platelet membrane receptors or adhesive proteins. These compounds may prove useful when immediate and potent inhibition of the hemostatic system is desired. Intensive research is still needed in the areas of pathogenesis and therapeutic intervention in atherosclerosis. PMID:2203564

Fuster, V; Stein, B; Ambrose, J A; Badimon, L; Badimon, J J; Chesebro, J H

1990-09-01

274

Thrombosis formation on atherosclerotic lesions and plaque rupture.  

PubMed

Atherosclerosis is a silent chronic vascular pathology that is the cause of the majority of cardiovascular ischaemic events. The evolution of vascular disease involves a combination of endothelial dysfunction, extensive lipid deposition in the intima, exacerbated innate and adaptive immune responses, proliferation of vascular smooth muscle cells and remodelling of the extracellular matrix, resulting in the formation of an atherosclerotic plaque. High-risk plaques have a large acellular lipid-rich necrotic core with an overlying thin fibrous cap infiltrated by inflammatory cells and diffuse calcification. The formation of new fragile and leaky vessels that invade the expanding intima contributes to enlarge the necrotic core increasing the vulnerability of the plaque. In addition, biomechanical, haemodynamic and physical factors contribute to plaque destabilization. Upon erosion or rupture, these high-risk lipid-rich vulnerable plaques expose vascular structures or necrotic core components to the circulation, which causes the activation of tissue factor and the subsequent formation of a fibrin monolayer (coagulation cascade) and, concomitantly, the recruitment of circulating platelets and inflammatory cells. The interaction between exposed atherosclerotic plaque components, platelet receptors and coagulation factors eventually leads to platelet activation, aggregation and the subsequent formation of a superimposed thrombus (i.e. atherothrombosis) which may compromise the arterial lumen leading to the presentation of acute ischaemic syndromes. In this review, we will describe the progression of the atherosclerotic lesion along with the main morphological characteristics that predispose to plaque rupture, and discuss the multifaceted mechanisms that drive platelet activation and subsequent thrombus formation. Finally, we will consider the current scientific challenges and future research directions. PMID:25156650

Badimon, L; Vilahur, G

2014-12-01

275

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.

276

Ruptured abdominal aortic aneurysm presenting as buttock pain.  

PubMed

This is the first case report of a ruptured aortic aneurysm presenting with acute right buttock pain. The patient was an 80 year old man. A literature search revealed one report of ruptured internal iliac artery aneurysm presenting with acute hip pain and another of an unruptured aortic aneurysm presenting with chronic hip pain. Thus the present case is another unusual presentation of ruptured abdominal aortic aneurysm and highlights the importance of careful history taking and clinical examination. A high index of clinical suspicion of aneurysm rupture should be maintained in elderly patients presenting with a history of collapse. PMID:15911962

Mahmood, F; Ahsan, F; Hockey, M

2005-06-01

277

The Modulus of Rupture from a Mathematical Point of View  

NASA Astrophysics Data System (ADS)

The goal of this work is to present a complete mathematical study about the three-point bending experiments and the modulus of rupture of brittle materials. We will present the mathematical model associated to three-point bending experiments and we will use the asymptotic expansion method to obtain a new formula to calculate the modulus of rupture. We will compare the modulus of rupture of porcelain obtained with the previous formula with that obtained by using the classic theoretical formula. Finally, we will also present one and three-dimensional numerical simulations to compute the modulus of rupture.

Quintela, P.; Sánchez, M. T.

2007-04-01

278

Simulations of pickup ion mediated quasi-perpendicular shocks: Implications for the heliospheric termination shock  

NASA Astrophysics Data System (ADS)

The microstructure of the heliospheric termination shock and the accompanied local acceleration processes of both ions and electrons are investigated by utilizing one-dimensional full particle-in-cell simulations for a variety of parameters. The relative pickup ion density is assumed to be 20-30%. The magnetic field and the shock potential profiles exhibit significant differences, since the former mostly reflects the dynamics of solar wind ions, whereas the latter is mainly sustained by the bulk motion of the reflected pickup ions in the extended foot. The discrepancy between the magnetic field profile and the potential profile increases with Alfvén Mach number. Most of the downstream thermal energy is gained by the pickup ions, while some heating of the solar wind ions and electrons occurs through the modified two-stream instability excited in the extended foot. Self-reformation can occur when the relative pickup ion density is 20% but is blurred when it becomes as large as 30%. Reformation is also suppressed if the local solar wind ion temperature in the extended foot is high, which can either be due to heating by the modified two-stream instability or is already determined by the solar wind temperature far upstream. In all runs presented in this study no evidence for shock surfing acceleration of pickup ions could be found. Nonthermal particle acceleration occurs for oblique shocks. Electron (pickup ion) shock drift acceleration is evidenced when the shock angle is below 80° (60°).

Matsukiyo, Shuichi; Scholer, Manfred

2014-04-01

279

Large > 10 m coseismic oblique slip along the rupture of the Mw 7.9 12 May 2008 Wenchuan earthquake (Sichuan, China)  

Microsoft Academic Search

At 02:28:01pm (06:28:01utc), on 12th May 2008, an Mw 7.9 (Ms 8.0) earthquake ruptured in the Longmen Shan along the eastern margin of the Tibetan Plateau in Sichuan, China. The epicenter was located inside the mountain range (N30.989°, E103.329°) in Wenchuan County. Field survey after the event allowed locating ruptures along the NE striking Longmenshan fault belt, that show mainly

H. Li; J. van der Woerd; P. Tapponnier; Z. Wang; X. Fu; L. Hou; J. Si; Z. Qiu

2009-01-01

280

Heliospheric shocks and catastrophe theory  

NASA Technical Reports Server (NTRS)

Various configurations of forward and reverse shocks that occur in the outer heliosphere can be classified using catastrophe theory. The existence of a forward shock is associated with a local maximum of a polynomial, and the existence of a reverse shock is associated with a local minimum of a polynomial. A configuration with N forward shocks and N reverse shocks corresponds to a polynomial with N maxima and N minima. The formation of forward and reverse shocks corresponds to the creation of maxima and minima of a polynomial, which is described by the separatrices of the catastrophes. The coalescence of two forward (reverse) shocks corresponds to the situation when two maxima (minima) of a polynomial have equal values, and the interaction of a forward shock with a reverse shock corresponds to a polynomial with a local maximum equal to a local minimum; these situations are described by the Maxwell sets of the appropriate catastrophes.

Burlaga, L. F.

1990-01-01

281

Probabilities of occurrence of large plate rupturing earthquakes for the San Andreas, San Jacinto, and Imperial faults, California, 1983--2003  

SciTech Connect

The San Andreas, San Jacinto, and Imperial faults in California are divided into 19 segments; conditional probabilities are calculated that a particular segment will be the site of a large plate rupturing earthquake, i.e., an event that breaks the entire down-dip extent of the seismogenic zone, during the next 20 years. The sizes of such events, which account for most of the slip that occurs seismically, appear to vary greatly for different segments of these faults. Repeat time of large shocks, coseismic displacement, moment release, rupture length, and seismic magnitude appear to correlated with one another and to be a function of the tectonic style of different parts of those fault zones. Tectonic inhomogeneities on a scale of about 1 to 100 km are much larger than displacement in any single seismic event and may be regarded as being invariant in their effects upon earthquake generation over many cycles of large shocks. It is this invariance that appears to lead to a given segment of a fault rupturing repeatedly in events of nearly the same size. Since repeat time varies, however, for a given segment of a fault, a simple probabilistic approach is used to forecast the likelihood of large future earthquakes for each segment, using as input the time of the last large shock, the average recurrence time, and the standard deviation of time intervals between events. Dates of the last large shocks are available for most of the segments investigated. Repeat times are estimated from times of historic and prehistoric events, tectonic similarity, and times calculated from coseismic displacement in the last large shock divided by a rate of fault motion or strain buildup.

Sykes, L.R.; Nishenko, S.P.

1984-07-10

282

Shock recovery experiments: An assessment  

SciTech Connect

Systematic shock recovery experiments, in which microstructural and mechanical property effects are characterized quantitatively, constitute an important means of increasing our understanding of shock processes. Through studies of the effects of variations in metallurgical and shock loading parameters on structure/property relationships, the micromechanisms of shock deformation, and how they differ from conventional strain rate processes, are beginning to emerge. This paper will highlight the state-of-the-art in shock recovery of metallic and ceramic materials. Techniques will be described which are utilized to ''soft'' recover shock-loaded metallic samples possessing low residual strain; crucial to accurate ''post-mortem'' metallurgical investigations of the influence of shock loading on material behavior. Illustrations of the influence of shock assembly design on the structure/property relationships in shock-recovered copper samples including such issues as residual strain and contact stresses, and their consequences are discussed. Shock recovery techniques used on brittle materials will be reviewed and discussed in light of recent experimental results. Finally, shock recovery structure/property results and VISAR data on the /alpha/--/omega/ shock-induced phase transition in titanium will be used to illustrate the beneficial link between shock recovery and ''real-time'' shock data. 26 refs., 3 figs.

Gray, G.T. III

1989-01-01

283

Wildlife Habitat of Maine  

Microsoft Academic Search

The Wildlife Habitat of Maine map was created using data from the Maine Office of GIS and the United States National Atlas. The map shows the land cover characteristics of Maine, including human development and major roads. The most suitable wildlife habitat can be attributed to the areas with the most suitable land cover and the least human development. An

Wendy Sicard

2005-01-01

284

Shock interactions with magnetized interstellar clouds. 1: Steady shocks hitting nonradiative clouds  

NASA Technical Reports Server (NTRS)

We study the interaction of a steady, planar shock with a nonradiative, spherical, interstellar cloud threaded by a uniform magnetic field. For strong shocks, the sonic Mach number scales out, so two parameters determine the evolution: the ratio of cloud to intercloud density, and the Alfven Mach number. We focus on the case with initial field parallel to the shock velocity, though we also present one model with field perpendicular to the velocity. Even with 100 zones per cloud radius, we find that the magnetic field structure converges only at early times. However, we can draw three conclusions from our work. First, our results suggest that the inclusion of a field in equipartition with the preshock medium can prevent the complete destruction of the cloud found in the field-free case recently considered by Klein, McKee, & Colella. Second, the interaction of the shock with the cloud can amplify the magnetic field in some regions up to equipartition with the post-shock thermal pressure. In the parallel-field case, the shock preferentially amplifies the parallel component of the field, creating a 'flux rope,' a linear structure of concentrated magnetic field. The flux rope dominates the volume of amplified field, so that laminar, rather than turbulent, amplification is dominant in this case. Third, the presence of the cloud enhances the production of X-ray and synchrotron emission. The X-ray emission peaks early, during the initial passage of the shock over the cloud, while the synchrotron emission peaks later, when the flow sweeps magnetic field onto the axis between the cloud and the main shock.

Low, Mordecai-Mark Mac; Mckee, Christopher F.; Klein, Richard I.; Stone, James M.; Norman, Michael L.

1994-01-01

285

Density-transition scale at quasiperpendicular collisionless shocks.  

PubMed

Measurements of a spacecraft floating potential, on the four Cluster spacecraft, are used as a proxy for electron plasma density to study, for the first time, the macroscopic density transition scale at 98 crossings of the quasiperpendicular terrestrial bow shock. A timing analysis gives shock speeds and normals; the shock speed is used to convert the temporal measurement to a spatial one. A hyperbolic tangent function is fitted to each density transition, which captures the main shock transition, but not overshoot or undershoot nor foot features. We find that, at a low Mach number M, the density transition is consistent with both ion inertial scales c/omega(pi) and convected gyroradii v(sh,n)/Omega(ci,2), while at M>/=4-5 only the convected gyroradius is the preferred scale for the shock density transition and takes the value L approximately 0.4v(sh,n)/Omega(ci,2). PMID:14754061

Bale, S D; Mozer, F S; Horbury, T S

2003-12-31

286

Shock aurora: Ground-based imager observations  

NASA Astrophysics Data System (ADS)

This paper studies dayside shock aurora forms and their variations observed by the ground-based all-sky imager (ASI) in Svalbard on 30 November 1997. The interplanetary shock arrived at Earth when Svalbard was at ˜1120 magnetic local time. The ASI detected an auroral intensification by a factor of 2 or more in both green and red line emissions within 5 min after the shock arrival. The intensified green emissions were mainly diffuse aurora on closed field lines. They were latitudinally below and adjacent to the red aurora, which was mainly in the form of arcs and beams along the magnetic east-west direction. The diffuse aurora expanded equatorward and eastward, and its intensity exceeded the red arcs that were at ˜5 kR. We confirmed that the eastward propagating diffuse aurora was actually moved antisunward along the oval, which suggests that the antisunward propagating shock aurora seen in space is mainly diffuse aurora. The intense diffuse aurora could be caused by wave instabilities led by a temperature anisotropy and/or caused by an enlarged loss cone. After the shock arrival, the detected low-latitude boundary of the cusp moved equatorward at a speed of ˜18 km min-1. As a result, the cusp meridional width was doubled from ˜0.8° to 1.6° in latitude in 10 min. This finding implies that a low-latitude reconnection occurred during the compression. In this study the auroral signatures and speculated mechanisms are consistent with those revealed by in situ particle and wave observations from FAST and DMSP.

Zhou, X.-Y.; Fukui, K.; Carlson, H. C.; Moen, J. I.; Strangeway, R. J.

2009-12-01

287

Numerical overcooling in shocks  

NASA Astrophysics Data System (ADS)

We present a study of cooling in radiative shocks simulated with smoothed particle hydrodynamics and adaptive mesh refinement codes. We obtain a similarity solution for a shock-tube problem in the presence of radiative cooling, and test how well the solution is reproduced in GADGET and FLASH. Shock broadening governed by the details of the numerical scheme (artificial viscosity or Riemann solvers) leads to potentially significant overcooling in both codes. We interpret our findings in terms of a resolution criterion, and apply it to realistic simulations of cosmological accretion shocks on to galaxy haloes, cold accretion and thermal feedback from supernovae or active galactic nuclei (AGN). To avoid numerical overcooling of accretion shocks on to haloes that should develop a hot corona a particle or cell mass resolution of 106 M? is required, which is within reach of current state-of-the-art simulations. At this mass resolution, thermal feedback in the interstellar medium of a galaxy requires temperatures of supernova- or AGN-driven bubbles to be in excess of 107 K at densities of nH= 1.0 cm-3, in order to avoid spurious suppression of the feedback by numerical overcooling.

Creasey, Peter; Theuns, Tom; Bower, Richard G.; Lacey, Cedric G.

2011-08-01

288

Posterior cerebral artery angle and the rupture of basilar tip aneurysms.  

PubMed

Since the initial publication of the International Study of Unruptured Intracranial Aneurysms (ISUIA), management of unruptured intracranial aneurysms has been mainly based on the size of the aneurysm. The contribution of morphological characteristics to treatment decisions of unruptured aneurysms has not been well studied in a systematic and location specific manner. We present a large sample of basilar artery tip aneurysms (BTA) that were assessed using a diverse array of morphological variables to determine the parameters associated with ruptured aneurysms. Demographic and clinical risk factors of aneurysm rupture were obtained from chart review. CT angiograms (CTA) were evaluated with Slicer, an open source visualization and image analysis software, to generate 3-D models of the aneurysms and surrounding vascular architecture. Morphological parameters examined in each model included aneurysm volume, aspect ratio, size ratio, aneurysm angle, basilar vessel angle, basilar flow angle, and vessel to vessel angles. Univariate and multivariate analyses were performed to determine statistical significance. From 2008-2013, 54 patients with BTA aneurysms were evaluated in a single institution, and CTAs from 33 patients (15 ruptured, 18 unruptured) were available and analyzed. Aneurysms that underwent reoperation, that were associated with arteriovenous malformations, or that lacked preoperative CTA were excluded. Multivariate logistic regression revealed that a larger angle between the posterior cerebral arteries (P1-P1 angle, p?=?0.037) was most strongly associated with aneurysm rupture after adjusting for other morphological variables. In this location specific study of BTA aneurysms, the larger the angle formed between posterior cerebral arteries was found to be a new morphological parameter significantly associated with ruptured BTA aneurysms. This is a physically intuitive parameter that can be measured easily and readily applied in the clinical setting. PMID:25353989

Ho, Allen L; Mouminah, Amr; Du, Rose

2014-01-01

289

Posterior Cerebral Artery Angle and the Rupture of Basilar Tip Aneurysms  

PubMed Central

Since the initial publication of the International Study of Unruptured Intracranial Aneurysms (ISUIA), management of unruptured intracranial aneurysms has been mainly based on the size of the aneurysm. The contribution of morphological characteristics to treatment decisions of unruptured aneurysms has not been well studied in a systematic and location specific manner. We present a large sample of basilar artery tip aneurysms (BTA) that were assessed using a diverse array of morphological variables to determine the parameters associated with ruptured aneurysms. Demographic and clinical risk factors of aneurysm rupture were obtained from chart review. CT angiograms (CTA) were evaluated with Slicer, an open source visualization and image analysis software, to generate 3-D models of the aneurysms and surrounding vascular architecture. Morphological parameters examined in each model included aneurysm volume, aspect ratio, size ratio, aneurysm angle, basilar vessel angle, basilar flow angle, and vessel to vessel angles. Univariate and multivariate analyses were performed to determine statistical significance. From 2008–2013, 54 patients with BTA aneurysms were evaluated in a single institution, and CTAs from 33 patients (15 ruptured, 18 unruptured) were available and analyzed. Aneurysms that underwent reoperation, that were associated with arteriovenous malformations, or that lacked preoperative CTA were excluded. Multivariate logistic regression revealed that a larger angle between the posterior cerebral arteries (P1-P1 angle, p?=?0.037) was most strongly associated with aneurysm rupture after adjusting for other morphological variables. In this location specific study of BTA aneurysms, the larger the angle formed between posterior cerebral arteries was found to be a new morphological parameter significantly associated with ruptured BTA aneurysms. This is a physically intuitive parameter that can be measured easily and readily applied in the clinical setting. PMID:25353989

Ho, Allen L.; Mouminah, Amr; Du, Rose

2014-01-01

290

Physics issues for shock ignition  

NASA Astrophysics Data System (ADS)

The paper presents theoretical analysis and experimental results concerning the major physical issues in the shock-ignition approach. These are the following: generation of a high amplitude shock in the imploding target, laser-plasma interaction physics under the conditions of high laser intensities needed for high amplitude shock excitation, symmetry and stability of the shock propagation, role of fast electrons in the symmetrization of the shock pressure and the fuel preheat. The theoretical models and numerical simulations are compared with the results of specially designed experiments on laser plasma interaction and shock excitation in plane and spherical geometries.

Batani, D.; Baton, S.; Casner, A.; Depierreux, S.; Hohenberger, M.; Klimo, O.; Koenig, M.; Labaune, C.; Ribeyre, X.; Rousseaux, C.; Schurtz, G.; Theobald, W.; Tikhonchuk, V. T.

2014-05-01

291

Infrared diagnostics of interstellar shocks  

NASA Technical Reports Server (NTRS)

The observations and theoretical models concerning interstellar shock waves are discussed. Interstellar shock waves are generated by the supersonic injection of mass into the interstellar medium by young stellar objects, by stellar winds, and by supernovae. Infrared emission lines from the heated, shocked gas provide valuable diagnostics of the density, temperature, velocity field, elemental abundances and extent of the emitting region. It is shown that the comparison of observed spectra from shocked regions with theoretical shock models can provide an estimate of the shock speed and the physical conditions in the preshock gas, including the ionization fraction and the magnetic field strength.

Hollenbach, D. J.; Chernoff, D. F.; Mckee, C. F.

1989-01-01

292

Poxvirus membrane biogenesis: rupture not disruption  

PubMed Central

Summary Enveloped viruses acquire their membrane from the host by budding at, or wrapping by, cellular membranes. Transmission electron microscopy (TEM) images, however, suggested that the prototype member of the poxviridae, vaccinia virus (VACV), may create its membrane ‘de novo’ with free open ends exposed in the cytosol. Within the frame of the German-wide priority programme we re-addressed the biogenesis and origin of the VACV membrane using electron tomography (ET), cryo-EM and lipid analysis of purified VACV using mass spectrometry (MS). This review discussed how our data led to a model of unconventional membrane biogenesis involving membrane rupture and the generation of a single open membrane from open membrane intermediates. Lipid analyses of purified virus by MS suggest an ER origin with a relatively low cholesterol content compared with whole cells, confirming published data. Unlike previous reports using thin-layer chromatography, no depletion of phosphatidylethanolamine was detected. We did detect, however, an enrichment for phosphatidic acid, diacylglycerol and phosphatidylinositol in the virion. Our data are discussed in the light of other pathogens that may require cellular membrane rupture during their intracellular life cycle. PMID:23168015

Locker, Jacomine Krijnse; Chlanda, Petr; Sachsenheimer, Timo; Brugger, Britta

2014-01-01

293

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

294

Management of extensor mechanism rupture after TKA.  

PubMed

Disruption of the extensor mechanism in total knee arthroplasty may occur by tubercle avulsion, patellar or quadriceps tendon rupture, or patella fracture, and whether occurring intra-operatively or post-operatively can be difficult to manage and is associated with a significant rate of failure and associated complications. This surgery is frequently performed in compromised tissues, and repairs must frequently be protected with cerclage wiring and/or augmentation with local tendon (semi-tendinosis, gracilis) which may also be used to treat soft-tissue loss in the face of chronic disruption. Quadriceps rupture may be treated with conservative therapy if the patient retains active extension. Component loosening or loss of active extension of 20° or greater are clear indications for surgical treatment of patellar fracture. Acute patellar tendon disruption may be treated by primary repair. Chronic extensor failure is often complicated by tissue loss and retraction can be treated with medial gastrocnemius flaps, achilles tendon allografts, and complete extensor mechanism allografts. Attention to fixing the graft in full extension is mandatory to prevent severe extensor lag as the graft stretches out over time. PMID:23118397

Rosenberg, A G

2012-11-01

295

[Spontaneous rupture of the spleen disclosing pheochromocytoma].  

PubMed

The authors report a case of spontaneous rupture of spleen inaugurating the symptomatology of a pheochromocytoma. After presenting the observation, clinical problems are considered with a deceptive abdominal symptomatology and myocardial ischemia that could be part of an "adrenergic myocarditis"; the mechanism of ruptured spleen is analyzed. The diagnosis approach is discussed through a reliability study of various explorations: computed tomography has a sensitivity ranging from 93 to 97% which approaches 100% when associated with magnetic resonance, methyl-iodo-benzyl-guanidine scanning seems to be provided with similar reliability. During checking up for pheochromocytoma spreading, ectopic location was not found, but a cold thyroid nodule was detected which allowed suspecting a SIPPLE syndrome. The three-stage surgical approach was required by symptomatology, hemostasis splenectomy, lateral pheochromocytoma excision after a short preparation by blocking alpha and beta, and then total thyroidectomy after extemporaneous confirmation of the existence of a medullary carcinoma of the thyroid. This pathologic association leading to a SIPPLE syndrome is listed as part of the multiple endocrine neoplasias of type II (MEN II). PMID:2262521

Carles, J; Guegan, H; Crozat, T; Janvier, G; Riant, T; Videau, J

1990-10-01

296

GPU Acceleration of Support Operator Rupture Dynamics  

NASA Astrophysics Data System (ADS)

SORD (Support Operator Rupture Dynamics) is an open-source software based on a fourth-order finite-difference method which can simulate 3D elastic wave propagation and spontaneous rupture on hexahedral mesh. It can be used for many kinds of surface boundary conditions, including free surface. The original software is developed by Geoffrey Ely from USC and modified by us for acceleration on GPU with NVIDIA CUDA. Our motivation on accelerating SORD on GPU is inspired by new generation GPU’s superior ability on general purpose computing and NVIDIA CUDA’s user-friendly developing environment for academic users. After translating the code from Fortran 95 to CUDA and implementing the transformed CUDA SORD code on the NVIDIA Tesla C1060, we obtained a factor of 6 speedup as compared to the original Fortran 95 version code , which was run on Intel Xeon X5570 2.9GHz. Our 3D wave solutions show explicitly visually in 3D format the different propagating wave fronts associated with the P and S waves according to the appropriate elastic parameter ratios. Because of the limitation of the global memory of NVIDIA Tesla C1060, too many more grid points would slow the calculation. However, by using the new NVIDIA Tesla C2070, which has 6 GBytes global memory, we can increase the simulation data size into 350X350X350.

Zhou, Y.; Dong, T.; Yuen, D. A.

2010-12-01

297

Principles and application of shock-tubes and shock tunnels  

NASA Technical Reports Server (NTRS)

The principles, theoretical flow equations, calculation techniques, limitations and practical performance characteristics of basic and high performance shock tubes and shock tunnels are presented. Selected operating curves are included.

Ried, R. C.; Clauss, H. G., Jr.

1963-01-01

298

Characterisation of active faulting and earthquake hazard in the Mongolian Altay Mountains based on previously unknown ancient earthquake surface ruptures  

NASA Astrophysics Data System (ADS)

Earthquakes in continental collision zones are typically distributed across a region that may be several thousands of kilometres away from the main collisional margin. This far-field deformation is poorly understood in terms of how strain is distributed onto upper crustal faults, particularly because active faults can be difficult to identify in regions where historical seismicity is sparse. The collision between India and Asia forms the most impressive example of active continental deformation on earth, with several zones of faulting and uplift extending across a region over 2500 km wide. The Altay Mountains, in western Mongolia, are at the northern edge of the India-Asia collision zone. Active dextral strike-slip faults in the Altay have produced M 8 earthquakes (such as the 1931 Fu Yun earthquake), and according to GPS measurements, the region accommodates approximately 7 mm/yr of shortening. Surface ruptures of pre-historic earthquakes are exceptionally preserved due to the cold and arid climate of the Altay. Observed surface ruptures are an effective extension to the historical seismic record, because the size and expression of ruptures may reveal important characteristics of the Altay active faults, such as typical earthquake magnitudes and definitive locations of active faults. We present observations of, previously unknown, surface ruptures and active faulting from the central Altay. The moment magnitudes of the ancient earthquakes are estimated based on the length of the ruptures using classic earthquake scaling laws. The newly discovered ruptures are combined with previously described earthquake ruptures to estimate the combined strike-slip rates of the Altay faults over the past ~1000 years on the basis of total moment release. This strike-slip rate will be discussed in the context of the modern-day estimates of shortening rate and the implications for the earthquake hazard in western Mongolia.

Gregory, L. C.; Walker, R.; Nissen, E.; Mac Niocaill, C.; Gantulga, B.; Amgalan, B.

2012-12-01

299

Spontaneous second-trimester ruptured pregnancy of rudimentary horn: a case report in Yaounde, Cameroon.  

PubMed

Rudimentary uterine horn pregnancy is rare and, to our knowledge, has not been previously reported in Cameroon. We herein report the case of a 22 year old second gravida referred for acute abdominal pain at 17 weeks of gestation. Physical examination revealed hemoperitoneum with hypovolemic shock. After resuscitation, an emergency exploratory laparotomy was done and we found hemoperitoneum of 3,500 milliliters, a bicornuate uterus with a ruptured right rudimentary communicating horn containing a non viable foetus. There were no other abnormalities. We performed an excision of the rudimentary horn with ipsilateral salpingectomy. Post-operative course was uneventful and the woman was discharged seven days later. This case emphasizes the importance of good antenatal care to avoid complications. PMID:25400853

Fouelifack, Florent Ymele; Fouogue, Jovanny Tsuala; Messi, John Owoudou; Kamga, Danielle Tiako; Fouedjio, Jeanne Hortence; Sando, Zacharie

2014-01-01

300

Surface Ruptures and Building Damage of the 2003 Bam, Iran, Earthquake Mapped by Satellite Synthetic Aperture Radar Interferometric Correlation  

NASA Technical Reports Server (NTRS)

We use the interferometric correlation from Envisat synthetic aperture radar (SAR) images to map the details of the surface ruptures related to the 26 December 2003 earthquake that devastated Bam, Iran. The main strike-slip fault rupture south of the city of Bam has a series of four segments with left steps shown by a narrow line of low correlation in the coseismic interferogram. This also has a clear expression in the field because of the net extension across the fault. Just south of the city limits, the surface strain becomes distributed over a width of about 500 m, probably because of a thicker layer of soft sedimentary material.

Fielding, Eric J.; Talebian, M.; Rosen, P. A.; Nazari, H.; Jackson, J. A.; Ghorashi, M.; Walker, R.

2005-01-01

301

Extracorporeal Shock Wave Treatment (ESWT) Improves In Vitro Functional Activities of Ruptured Human  

E-print Network

: Junming Yue, The University of Tennessee Health Science Center, United States of America Received August 7 Human Tendon-Derived Tenocytes Laura Leone1 , Mario Vetrano2,3 , Danilo Ranieri1 , Salvatore Raffa1, Rome, Italy, 3 Sant'Andrea Hospital, Rome, Italy Abstract In vitro models of human tenocytes derived

Boyer, Edmond

302

Emission lines and shock waves in RR Lyrae stars  

NASA Astrophysics Data System (ADS)

Context. Emission lines observed in radially pulsating stars are thought to be produced by atoms de-exciting after being excited by a shock wave that is traveling into and then compressing, heating, and accelerating the atmospheric gas. Aims: With the help of recent observations, we examine the origin of all the different types of emission lines of hydrogen and helium that appear during a pulsation cycle. Methods: To analyze the physical origin of emission lines, we used the different models of atmospheric dynamics of RR Lyrae stars that have been calculated so far. Results: In contrast to a recent explanation, we propose that the redshifted emission component of H?, which occurs near the pulsation phase 0.3, is produced by the main shock. In this case, the emission is the natural consequence of the large extension of the expanding atmosphere. Therefore, this (weak) emission should only be observed in RR Lyrae stars for which the main shock will propagate far enough from the photosphere. It appears as a P-Cygni type profile. We estimate the shock front velocity during the shock propagation in the atmosphere and show that it decreases by 40% when the H? emitting-shock passes from the photospheric level to the upper atmosphere. The H? P-Cygni profile observed in long-period Cepheids also seems to be caused by the main shock wave. Although to date He II has only been detected in some Blazhko stars, a comprehensive survey of RR Lyrae stars is necessary to confirm this trend, so we can say that the most intense shocks will only be observed in Blazhko stars. Conclusions: The development of a model of atmospheric pulsation that takes the effects of 2D and 3D convection into account, seems to be a necessary step to fully quantify the effects of shock waves on the atmospheric dynamics of radially pulsating stars.

Gillet, D.; Fokin, A. B.

2014-05-01

303

Impact-shocked zircons: discovery of shock-induced textures reflecting increasing degrees of shock metamorphism  

USGS Publications Warehouse

Textural effects specifically characteristic of shock metamorphism in zircons from impact environments have not been reported previously. However, planar deformation features (PDF) due to shock metamorphism are well documented in quartz and other mineral grains from these same environments. An etching technique was developed that allows SEM visualization of PDF and other probable shock-induced textural features, such as granular (polycrystalline) texture, in zircons from a variety of impact shock environments. These textural features in shocked zircons from K/T boundary distal ejecta form a series related to increasing degrees of shock that should correlate with proportionate resetting of the UPb isotopic system. ?? 1993.

Bohor, B. F.; Betterton, W. J.; Krogh, T. E.

1993-01-01

304

Interaction between shock wave and unsteady jet in shock tube  

Microsoft Academic Search

Recent observations of the interaction between a shock wave and an unsteady jet in a shock tube demonstrated the temporary generation of a hemispherical reflected shock wave. A numerical computation which solved for the axisymmetric viscous flow on the basis of the MacCormack method is presently conducted to clarify the causes of this strong interaction. Essential agreement is obtained between

Yoshimi Ishii; Fumio Takayama

1990-01-01

305

Heat shock proteins and effects of heat shock in plants  

Microsoft Academic Search

Soybean seedlings when exposed to a heat shock respond in a manner very similar to that exhibited by cultured cells, and reported earlier [2]. Maximum synthesis of heat shock proteins (HSPs) occurs at 40C. The heat shock response is maintained for a relatively short time under continuous high temperature. After 2.5 hr at 40 C the synthesis of HSPs decreases

Mitchell Altschuler; Joseph P. Mascarenhas

1982-01-01

306

Shock destruction armor system  

DOEpatents

A shock destruction armor system is constructed and arranged to destroy the force of impact of a projectile by shock hydrodynamics. The armor system is designed to comprise a plurality of superimposed armor plates each preferably having a thickness less than five times the projectile's diameter and are preferably separated one-from-another by a distance at least equal to one-half of the projectile's diameter. The armor plates are effective to hydrodynamically and sequentially destroy the projectile. The armor system is particularly adapted for use on various military vehicles, such as tanks, aircraft and ships.

Froeschner, Kenneth E. (Livermore, CA)

1993-01-01

307

Methods of Monitoring Shock  

PubMed Central

Intensive monitoring is a crucial component of the management of shock. However, there is little consensus about optimal strategies for monitoring. Although the pulmonary artery catheter has been widely used, conflicting data exist about the utility of this device. A variety of other techniques have been developed in hopes of providing clinically useful information about myocardial function, intravascular volume, and indices of organ function. In addition, there is evolving evidence that targeting and monitoring certain physiological goals may be most important early in the course of shock. In this chapter, we examine many of the available monitoring techniques and the evidence supporting their use. PMID:16088506

Bajwa, Ednan K.; Malhotra, Atul; Thompson, B. Taylor

2012-01-01

308

Skin surface shock wave.  

PubMed

This paper discusses the Skin Surface Shock Wave which is generated after we impart an impulsive force to human skin. The force is given by an air jet during 200 [ms]. The basic behavior of shock wave is measured by a high speed camera with the frame rate of 2000 [Hz]. Through the experiment, we found an interesting behavior where there exists a remarkable difference between young and elder subjects especially during the recovery phase, while there is nearly no difference between two during the force imparting phase. PMID:17946225

Tanaka, Nobuyuki; Kaneko, Makoto

2006-01-01

309

Percutaneous Treatment of Sac Rupture in Abdominal Aortic Aneurysms Previously Excluded with Endovascular Repair (EVAR)  

SciTech Connect

The purpose of this study was to assess the feasibility and effectiveness of percutaneous endovascular repair of ruptured abdominal aortic aneurysms (AAAs) previously treated by EVAR. In the last year, two male patients with AAAs, treated 8 and 23 months ago with bifurcated stent-graft, were observed because of lumbar pain and hemorragic shock. Multidetector computed tomography (MDCT) showed a retroperitoneal hematoma; in both cases a type III endoleak was detected, in one case associated with a type II endoleak from the iliolumbar artery. The procedures were performed in the theater, in emergency. Type II endoleak was treated with transcatheter superselective glue injection; type III endoleaks were excluded by a stent-graft extension. The procedures were successful in both patients, with immediate hemodynamic stabilization. MDCT after the procedure showed complete exclusion of the aneurysms. In conclusion, endovascular treatment is a safe and feasible option for the treatment of ruptured AAAs previously treated by EVAR; this approach allows avoidance of surgical conversion, which is technical very challenging, with a high morbidity and mortality rate.

Lagana, Domenico, E-mail: donlaga@gmail.com; Mangini, Monica, E-mail: monica.mangini@tin.it; Fontana, Federico; Nicotera, Paolo; Carrafiello, Gianpaolo; Fugazzola, Carlo [University of Insubria, Vascular and Interventional Radiology, Department of Radiology (Italy)

2009-01-15

310

Ruptured renal arteriovenous malformation successfully treated by catheter embolization: a case report  

PubMed Central

Background Renal arteriovenous fistula (RAVF) is a comparatively rare malformation. Here, we report a case of ruptured RAVF that was successfully treated by catheter embolization. Case presentation An 89-year-old female was transferred to our institution with massive gross hematuria in March 2011. Plain abdominal computed tomography (CT) revealed dilated left renal pelvis with high-density contents. Hematoma was suspected. Subsequent plain abdominal magnetic resonance imaging revealed left hydronephrosis and blood retention in the dilated left renal pelvis. No renal or ureteral cancer was evident. Hematuria was conservatively treated using hemostatic agents but hematuria persisted. Repeated urinary cytology revealed no malignant cells. On day 9, the patient went into septic and/or hemorrhagic shock. Fluid and catecholamine infusion, blood transfusion, and antibacterial drugs were rapidly initiated, and the patient’s general condition gradually improved. Contrast-enhanced abdominal CT revealed marked expansion of the hematoma in the renal pelvis and microaneurysms in the segmental arteries of the left kidney. Inflammation improved, and a left double-J stent was inserted. Selective renal angiography revealed RAVF with microaneurysms in the left segmental arteries; therefore, catheter embolization using metallic coils was performed, which resolved hematuria. Conclusion We report a case of ruptured renal arteriovenous malformation, which was successfully treated by catheter embolization. PMID:24405847

2014-01-01

311

Ruptured abdominal aortic aneurysm presenting as buttock pain  

Microsoft Academic Search

This is the first case report of a ruptured aortic aneurysm presenting with acute right buttock pain. The patient was an 80 year old man. A literature search revealed one report of ruptured internal iliac artery aneurysm presenting with acute hip pain and another of an unruptured aortic aneurysm presenting with chronic hip pain. Thus the present case is another

F Mahmood; F Ahsan; M Hockey

2005-01-01

312

The Resolution of Ruptures in the Therapeutic Alliance.  

ERIC Educational Resources Information Center

A rupture in the therapeutic alliance is a deterioration in the quality of the relationship between patient and therapist; it is an interpersonal marker that indicates an opportunity for exploring and understanding the processes that maintain a maladaptive interpersonal schema. Outlines features of a research program on ruptures in the therapeutic…

Safran, Jeremy D.; Muran, J. Christopher

1996-01-01

313

Rupture of major bronchi resulting from closed chest injuries  

PubMed Central

Four cases of ruptured bronchus following closed chest trauma are described. All injuries resulted from motor vehicle accidents and were diagnosed and treated within 24 hours of admission to the hospital. A satisfactory result followed early suture repair of the ruptured bronchus in three cases. One patient died during pneumonectomy. The early diagnosis and treatment of the condition are discussed. Images PMID:4724503

Collins, John P.; Ketharanathan, V.; McConchie, Ian

1973-01-01

314

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

315

Successful Patching of Iatrogenic Rupture of the Fetal Membranes  

Microsoft Academic Search

Rupture of the fetal membranes is a common, but potentially serious complication of invasive fetal procedures. Quintero described a technique to seal the fetal membrane defect by means of a bloodpatch, usually called ‘amniopatch’ in this application. The successful use in two consecutive patients with ruptured membranes after a fetoscopic intervention at respectively 17 and 22 weeks' gestational age is

L Lewi; D Van Schoubroeck; M Van Ranst; G Bries; M-P Emonds; B Arabin; R Welch; J Deprest

2004-01-01

316

Survivors of ruptured abdominal aortic aneurysm: the iceberg's tip  

Microsoft Academic Search

In four and a half years 25 patients in one community suffered a ruptured abdominal aortic aneurysm. Eleven died at home, nine died without operation in hospital, and only five had the aneurysm removed. There were four survivors. A further seven patients might have lived had they had a prompt operation. The average operative mortality for ruptured aneurysms among series

R H Armour

1977-01-01

317

How Is Cardiogenic Shock Diagnosed?  

MedlinePLUS

... To Diagnose Shock and Its Underlying Causes Blood Pressure Test Medical personnel can use a simple blood pressure ... the most common sign of shock. A blood pressure test can be done before the person goes to ...

318

[The results of treatment of the patients with the rupture of abdominal aortic aneurysms in multifield hospital].  

PubMed

The rupture of infrarenal segment of aorta is the severe pathology in spite of modem diagnostics and the operation. This case is accompanied by negative results of treatment (lethality consists of 56,3%). The article presents the experience of treatment of 157 patients with the rupture of infrarenal segment of aorta in conditions of multifield hospital (Municipal hospital No 26). The authors highlighted the postoperative complications, their influence on negative outcome. It was shown, that the main reasons of negative outcome of such patients with abdominal aortic aneurism, complicated by the rupture, were an advanced age of patients, who had the complex of concomitant diseases and postoperative complications such as nosocomial pneumonia, cardiac problems and multiple organ failure due to massive acute hemorrhage. PMID:24640754

Mosiagin, V B; Ryl'kov, V F; Moiseev, A A; Karpatski?, I V

2013-01-01

319

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

320

Shock compression of diamond crystal  

Microsoft Academic Search

Two shock wave experiments employing inclined mirrors have been carrried out to determine the Hugoniot elastic limit (HEL), final shock state at 191 and 217 GPa, and the post-shock state of diamond crystal, which is shock-compressed along the intermediate direction between the and crystallographic axes. The HEL wave has a velocity of 19.9+\\/-0.3 mm\\/musec and an amplitude of 63+\\/-28 GPa.

Ken-ichi Kondo; Thomas J. Ahrens

1983-01-01

321

Detonation structures behind oblique shocks  

Microsoft Academic Search

Detonation structures generated by wedge-induced, oblique shocks in hydrogen–oxygen–nitrogen mixtures were investigated by time-dependent numerical simulations. The simulations show a multidimensional detonation structure consisting of the following elements: (1) a nonreactive, oblique shock, (2) an induction zone, (3) a set of deflagration waves, and (4) a ‘‘reactive shock,’’ in which the shock front is closely coupled with the energy release.

Chiping Li; K. Kailasanath; Elaine S. Oran

1994-01-01

322

Maskelynite: Formation by explosive shock  

USGS Publications Warehouse

When high pressure (250 to 300 kilobars) was applied suddenly (shock-loading) to gabbro, the plagioclase was transformed to a noncrystalline phase (maskelynite) by a solid-state reaction at a low temperature, while the proxene remained crystalline. The shock-loaded gabbro resembles meteorites of the shergottite class; this suggests that the latter formed as a result of shock. The shock-loading of gabbro at 600 to 800 kilobars raised the temperature above the melting range of the plagioclase.

Milton, D.J.; De Carli, P. S.

1963-01-01

323

Rupture of Right Hepatic Duct into Hydatid Cyst  

PubMed Central

Echinococcal disease can develop anywhere in the human body. The liver represents its most frequent location. Hepatic hydatid cysts may rupture into the biliary tract, thorax, peritoneum, viscera, digestive tract or skin. We report a rare case with rupture of the right hepatic duct into a hydatid cyst in a woman with known hydatid disease and choledocholithiasis. The increased intra-luminal pressure in the biliary tree caused the rupture into the adjacent hydatid cyst. The creation of the fistula between the right hepatic duct and the hydatid cyst decompressed the biliary tree, decreased the bilirubin levels and offered a temporary resolution of the obstructive jaundice. Rupture of a hydatid cyst into the biliary tree usually leads to biliary colic, cholangitis and jaundice. However, in case of obstructive jaundice due to choledocholithiasis, it is possible that the cyst may rupture by other way around while offering the patient a temporary relief from his symptoms. PMID:22876065

Laskou, Styliani; Papavramidis, Theodossis S.; Pliakos, Ioannis; Kotidis, Eustathios; Kesisoglou, Isaak; Papavramidis, Spiros T.

2012-01-01

324

Malignant fibrous histiocytoma presenting as hemoperitoneum mimicking hepatocellular carcinoma rupture  

PubMed Central

Malignant fibrous histiocytoma (MFH) is a pleomorphic mesenchynal sarcoma. It is uncommonly arises primarily from the intra-peritoneal cavity. Primary peritoneal MFH with tumor bleeding and rupture is rare. We describe the imaging features of a 70-year-old patient presenting with ruptured hemorrhagic peritoneal MFH at subhepatic area, accompanied by massive hemoperitoneum, mimicking a ruptured pedunculated hepatocellular carcinoma. Computed tomography (CT) revealed a large heterogeneous enhanced subhepatic mass with adjacent liver, gallbladder and colon invasion. Tumor hemorrhage and rupture complicated with peritoneal seeding and massive bloody ascites were also detected. Angiography showed a hypervascular tumor fed by enlarged right hepatic arteries, cystic artery and omental branches of gastroepiploic artery. The patient underwent laparotomy for tumor resection, but the tumor recurred one month after operation. To our knowledge, the CT appearance of ruptured intraperitoneal MFH complicated by hemoperitoneum has not been previously described. PMID:18081238

Chen, Hsin-Chi; Chen, Chi-Jen; Jeng, Chin-Ming; Yang, Chan-Ming

2007-01-01

325

MAINE MARINE WORM HABITAT  

EPA Science Inventory

WORM provides a generalized representation at 1:24,000 scale of commercially harvested marine worm habitat in Maine, based on Maine Department of Marine Resources data from 1970's. Original maps were created by MDMR and published by USF&WS as part of the ""&quo...

326

Exploring Main Belt Asteroids  

Microsoft Academic Search

Terrestrial planet formation in the main asteroid belt was interrupted when growing protoplanets became sufficiently massive to gravitationally perturb the local population, causing bodies to collide with increased energy, thus ending accretion and commencing fragmentation and disruption. Few of these protoplanets are thought to have survived unshattered (e.g., Ceres, Vesta, Pallas), leaving a main belt population dominated by fragments of

M. V. Sykes; S. M. Larson; R. Whiteley; U. Fink; R. Jedicke; J. Emery; R. Fevig; M. Kelley; A. W. Harris; S. Ostro; K. Reed; R. P. Binzel; A. Rivkin; C. Magri; W. Bottke; D. Durda; R. Walker; D. Davis; W. K. Hartmann; D. Sears; H. Yano; J. Granahan; A. Storrs; S. J. Bus; J. F. Bell; D. Tholen; A. Cellino

2001-01-01

327

Development of Final A-Fault Rupture Models for WGCEP/ NSHMP Earthquake Rate Model 2  

USGS Publications Warehouse

This appendix discusses how we compute the magnitude and rate of earthquake ruptures for the seven Type-A faults (Elsinore, Garlock, San Jacinto, S. San Andreas, N. San Andreas, Hayward-Rodgers Creek, and Calaveras) in the WGCEP/NSHMP Earthquake Rate Model 2 (referred to as ERM 2. hereafter). By definition, Type-A faults are those that have relatively abundant paleoseismic information (e.g., mean recurrence-interval estimates). The first section below discusses segmentation-based models, where ruptures are assumed be confined to one or more identifiable segments. The second section discusses an un-segmented-model option, the third section discusses results and implications, and we end with a discussion of possible future improvements. General background information can be found in the main report.

Field, Edward H.; Weldon, Ray J., II; Parsons, Thomas; Wills, Chris J.; Dawson, Timothy E.; Stein, Ross S.; Petersen, Mark D.

2008-01-01

328

Aneurysm geometry in predicting the risk of rupture. A review of the literature.  

PubMed

The management of unruptured aneurysms (UAs), whose incidence is increasing, is still a controversial issue. Many studies have been investigating the link between the geometry of the aneurysm and the risk of future rupture in order to bring forth a clear decision plan. The different estimators studied are the aneurysm's geometry and hemodynamic features on one hand, and the patient's clinical characteristics on the other. We reviewed the literature while focusing on the different geometrical parameters that have been used in estimating the future risk of rupture. These include mainly the size ratio (SR), the aspect ratio, the non-sphericity index (NI), the undulation index (UI), and the vessel aneurysm inclination angle (AA), to name a few. PMID:24617931

Zanaty, Mario; Chalouhi, Nohra; Tjoumakaris, Stavropoula I; Fernando Gonzalez, L; Rosenwasser, Robert H; Jabbour, Pascal M

2014-04-01

329

Lipid membranes in external electric fields: kinetics of large pore formation causing rupture.  

PubMed

About 40 years ago, Helfrich introduced an elastic model to explain shapes and shape transitions of cells (Z Naturforsch C, 1973; 28:693). This seminal article stimulated numerous theoretical as well as experimental investigations and created new research fields. In particular, the predictive power of his approach was demonstrated in a large variety of lipid model system. Here in this review, we focus on the development with respect to planar lipid membranes in external electric fields. Stimulated by the early work of Helfrich on electric field forces acting on liposomes, we extended his early approach to understand the kinetics of lipid membrane rupture. First, we revisit the main forces determining the kinetics of membrane rupture followed by an overview on various experiments. Knowledge on the kinetics of defect formation may help to design stable membranes or serve for novel mechanism for controlled release. PMID:24485595

Winterhalter, Mathias

2014-06-01

330

New Occurrence of Shocked Graphite Aggregates at Barringer Crater  

NASA Astrophysics Data System (ADS)

High-pressure carbon minera]s are considered to be formed by solid-solid transformation under static or impact high-pressure condition, but shocked quartz aggregates of impact craters are considered to be formed by quenched accretion of various aggregates by dynamic impact process [1-3]. The main purpose of this study is to elucidate new findings and occurrences of shocked graphite (SG) aggregates [2,3] at the Barringer meteorite crater. The graphite nodule block of Barringer Crater used in this study is collected near the rim. The sample is compared with standard graphite samples of Korea, Madagascar, and artificial impact graphites. There are four different mineral aggregates of the Barringer graphite nodule sample: (1) shocked graphite-1, (2) shocked graphite-2 and hexagonal diamond in the vein, (3) shocked quartz-1 (with kamacite) in the rim, and (4) calcite in the rim (Table 1). X-ray diffraction peaks of shocked graphite reveal low X-ray intensity, high Bragg-angle shift of X-ray diffraction peak, and multiple splitting of X-ray diffraction peaks. X-ray calculated density (rho) has been determined by X-ray diffractometer by the equation of density deviation Delta rho (%) = 100 x {(rho-rho(sub)0)/rho(sub)0}, where standard density rho(sub)0 is 2.255 g/cm^3 in Korean graphite [2,3]. The high-density value of shocked graphite grain obtained in Barringer is Delta rho = +0.6 +/- 0.1%. Shocked hexagonal diamonds (chaoite) show a high value of Delta rho = +0.6 +/- 0.9%. Analytical electron microscopy data reveal three different aggregates in the graphite nodule samples (Table 1): (1) shocked graphite-1 in the matrix, which contains uniformly Fe and Ca elements formed under gas state; (2) shocked graphite-2 in the vein, where crystallized shocked graphites and hexagonal diamonds are surrounded by kamacite-rich metals formed under gas-melt states of mixed compositions from iron meteorite and target rocks; and (3) shocked quartz-1 and kamacite in the rim, where coexisted elements are supplied from kamacite, sandstone, and limestone. The shocked quartz-1 grains with high density contain Fe and Ca elements that are different from the shocked quartz-2 of pure silica [1] formed at the final stage from the Coconino sandstone. (4) Limestone in the rim is attached from Kaibab limestone. The present shocked graphites with high density are the same as artificial fine-grained shocked graphites (Delta rho = +0.7%). Table 1, which appears here in the hard copy, shows formation stages with two shocked graphites in the Barringer Crater. Formation of shocked aggregates with chemical contamination indicate dynamic accretion processes of quenching and depression at impact. The existence of two shocked graphites indicates the two formation stages of the first gas-state and the second gas-melt states with quenching processes. The origin of carbon in the shocked graphites is considered in this study to be from Kaibab limestone. References: [1] Miura Y. (1991) Shock Waves, 1, 35-41. [2] Miura Y. (1992) Proc. Shock Waves (Japan), 2, 54-57. [3] Miura Y. et al. (1993) Symp. NIPR Antarctic Meteorite (Tokyo), in press. [4] Foote A. E. (1891) Am. J. Sci., 42, 413-417. [5] Hannemann R. E. et al. (1967) Science, 155, 995-997.

Miura, Y.; Noma, Y.; Iancu, O. G.

1993-07-01

331

Gap Between Cascadia Megathrust Rupture Area and Episodic Tremor and Slip (ETS) Suggests Forearc Mantle Control of ETS  

NASA Astrophysics Data System (ADS)

The rupture area of the Cascadia megathrust and the areal extent of episodic tremor and slip (ETS) are both now quite well constrained. Rupture occurs mainly offshore whereas ETS lies mainly onshore. The gap between the two is approximately 50 km. The timing of when the fault moves within this gap relative to Cascadia earthquake and ETS cycles is not yet known. The megathrust rupture area has been constrained in a recent summary by the locked/transition zones defined from geodetic deformation, the seismic-aseismic transition defined by the temperature on the fault interface, the past rupture zone estimated from paleoseismic coastal marsh subsidence, the down-dip change in seismic reflection character of the fault interface, and rupture area associations with shelf-slope basins. The depths of the ETS tremor have some uncertainties, as illustrated by differences between several location methods, but are quite well determined in map view. The associated slow slip is less well determined in map view; several estimates locate it slightly seaward of the tremor. The megathrust down-dip limit is convincingly constrained by temperature. However, temperature does not appear to control the up-dip position of ETS as it occurs at variable temperatures along the margin. The best explanation appears to be that the ETS up-dip limit corresponds to the forearc mantle corner. Our compilation of the position of this corner gives general agreement, although there is still much uncertainty. ETS therefore may occur only beneath the forearc mantle with forearc serpentinite and talc likely playing a role. Other hot subduction zones where ETS is separated from the megathrust rupture area by a gap, such as SW Japan and Mexico, may provide insights into controls on Cascadia ETS occurrence as well as the timing of fault slip within the gap.

Hyndman, R. D.; McCrory, P. A.; Wech, A.

2013-12-01

332

SHOCK COMPRESSION PROCESSING OF POWDERS  

Microsoft Academic Search

Shock compression processing is emerging as a novel technique for fabrication of esoteric materials. Not only can metal and ceramic powders be dynamically consolidated, but both equilibrium and non-equilibrium structures can be synthesized under the high pressure regime during the passage of shock waves of sufficient magnitude and duration. The shock waves can be generated by impact from a plate

N. N. Thadhani

1988-01-01

333

Shock Waves in Granular Gases  

Microsoft Academic Search

This review is the first attempt to systematize the results on shock waves in granular gases. We present experimental and computational evidences of shock and expansion waves propagating within granular gases. The analysis of model flows with shock and expansion waves shows that even smallest kinetic energy dissipations crucially affects such flows. We discuss the role of these waves for

Alexander Goldshtein; Alexander Alexeev; Michael Shapiro

2003-01-01

334

Some like it cold: response of microorganisms to cold shock  

Microsoft Academic Search

Bacteria respond to an abrupt decrease in temperature with a specific response, in which cold-induced proteins (CIPs) are\\u000a transiently expressed at a higher level. Employing two-dimensional gel electrophoresis, several CIPs have been identified.\\u000a In spite of this, the overall function of the cold shock response is unclear. Recently, the main attention has focused on\\u000a a group of conserved cold shock

Peter Graumann; Mohamed A. Marahiel

1996-01-01

335

Macroscopic Source Properties from Dynamic Rupture Styles in Plastic Media  

NASA Astrophysics Data System (ADS)

High stress concentrations at earthquake rupture fronts may generate an inelastic off-fault response at the rupture tip, leading to increased energy absorption in the damage zone. Furthermore, the induced asymmetric plastic strain field in in-plane rupture modes may produce bimaterial interfaces that can increase radiation efficiency and reduce frictional dissipation. Off-fault inelasticity thus plays an important role for realistic predictions of near-fault ground motion. Guided by our previous studies in the 2D elastic case, we perform rupture dynamics simulations including rate-and-state friction and off-fault plasticity to investigate the effects on the rupture properties. We quantitatively analyze macroscopic source properties for different rupture styles, ranging from cracks to pulses and subshear to supershear ruptures, and their transitional mechanisms. The energy dissipation due to off-fault inelasticity modifies the conditions to obtain each rupture style and alters macroscopic source properties. We examine apparent fracture energy, rupture and healing front speed, peak slip and peak slip velocity, dynamic stress drop and size of the process and plastic zones, slip and plastic seismic moment, and their connection to ground motion. This presentation focuses on the effects of rupture style and off-fault plasticity on the resulting ground motion patterns, especially on characteristic slip velocity function signatures and resulting seismic moments. We aim at developing scaling rules for equivalent elastic models, as function of background stress and frictional parameters, that may lead to improved "pseudo-dynamic" source parameterizations for ground-motion calculation. Moreover, our simulations provide quantitative relations between off-fault energy dissipation and macroscopic source properties. These relations might provide a self-consistent theoretical framework for the study of the earthquake energy balance based on observable earthquake source parameters.

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

2011-12-01

336

Importance of heat shock proteins in maize  

Microsoft Academic Search

Abiotic and biotic stress conditions cause extensive losses to maize production, mainly due to protein dysfunction in these\\u000a conditions. In higher plants, the occurrence of heat-shock proteins (HSPs) in response to different environmental stresses\\u000a is a universal phenomenon and has been well documented. Many studies have demonstrated that most HSPs are involved in many\\u000a regulatory pathways, act as molecular chaperones

Camila Pegoraro; Liliane Marcia Mertz; Luciano Carlos da Maia; Cesar Valmor Rombaldi; Antonio Costa de Oliveira

2011-01-01

337

Shock Wave Phenomena in Coaxial Plasma Guns  

Microsoft Academic Search

In a plasma gun (or a magnetically driven shock tube) shocks are usually ; obscured by a luminous front. Using a reflection technique and a pressure probe, ; the existence of a shock wave is confirmed experimentally. For weak shocks the ; luminous front lags definitely behind the shock front. For strong shocks there ; is an indication that the

C. T. Chang

1961-01-01

338

Imaging Atherosclerosis and Risk of Plaque Rupture  

PubMed Central

Atherosclerosis imaging strategies can delineate characteristics of plaques at risk of rupture and thrombosis. Structural plaque imaging identifies high-risk plaque features including lipid pools, thin fibrous caps, and intraplaque hemorrhage, among others. New molecular imaging techniques complement structural imaging approaches by illuminating important features of plaque biology, with a prominent focus on detecting inflammation as a high-risk phenotype. As we unravel the molecular and structural characteristics underlying thrombosis-prone plaques, there is significant promise for eventual early identification and prediction of atherosclerotic plaque complications before they occur. Here we focus on recent imaging insights into high-risk arterial plaques, the etiologic agent of acute myocardial infarction (MI), stroke, and sudden cardiac death. PMID:23982263

Osborn, Eric A; Jaffer, Farouc A

2013-01-01

339

On MHD intermediate shocks  

Microsoft Academic Search

The numerical solution of resistive MHD equations, in order to show that some intermediate shocks are admissible, is described. A coplanar case with v(z) = Bz = 0, and a full MHD case with v(z) and Bz not equal to zero are studied. In the first cast no intermediate wave existed, but based on the solution of the equations intermediate

C. C. Wu

1987-01-01

340

Nonhemorrhagic Primary Obstetric Shock  

Microsoft Academic Search

Objective: Clinical evaluation of nonhemorrhagic primary obstetric shock (NHPOS). Methods: In a retrospective clinical study, data on 8 cases of NHPOS were analyzed. Data on patient age, parity, week of gestation, comorbidity, possible etiologic trigger, course of disease with clinical picture and laboratory findings of coagulopathy, and patient outcome including autopsy findings in two lethal outcomes were analyzed. Results: These

Dubravko Habek

2008-01-01

341

A Shocking New Pump  

NASA Technical Reports Server (NTRS)

Hydro Dynamics, Inc. received a technical helping hand from NASA that made their Hydrosonic Pump (HPump) a reality. Marshall engineers resolved a bearing problem in the rotor of the pump and recommended new bearings, housings and mounting hardware as a solution. The resulting HPump is able to heat liquids with greater energy efficiency using shock waves to generate heat.

2000-01-01

342

Rupture of the spleen or splenic vessels (splenic emergency syndrome) in late pregnancy: a report of two autopsy cases.  

PubMed

Emergencies of splenic origin in pregnancy involving rupture of the splenic artery or hemorrhage are rare events that can present suddenly and unexpectedly. We report two cases of young women, both in the third trimester of gestation, who suffered sudden malaise while at home and were admitted to the ER. On arrival, both were in severe hemorrhagic shock due to gross hemoperitoneum and they died in the operating theatre during emergency surgery. To better clarify the causes and sequence of these mortalities, forensic autopsy was requested in each case. In the first (a 26-year-old primigravida in the 40th week of pregnancy), cadaveric section demonstrated the rupture of an aneurysm of the splenic artery. In the second (a 28-year-old multipara in the 33rd week of pregnancy), the clinical and anatomopathological data suggested splenic hemorrhage. In both cases histology showed a fibrodysplasia of the arterial wall involving the splenic artery in one case and the hilar branches in the other. In agreement with the data in literature, in such cases particular importance must be attributed to examination of the arterial wall. In pregnancy a synergic effect between hemodynamic and endocrine factors can cause degeneration of the arteries resulting in dramatic hemorrhage. From the forensic pathologist's viewpoint, these cases underline the importance of histopathological study of the splenic artery in the interpretation of the pathogenesis of splenic vessel rupture or hemorrhage. PMID:17728086

Di Vella, Giancarlo; Arpaio, Alessandra; Marzullo, Andrea; Colonna, Massimo

2008-04-01

343

Shock Surface Undulation and Particle Acceleration at Oblique Shocks  

NASA Astrophysics Data System (ADS)

Considering the average Parker spiral magnetic field configuration, CME-driven interplanetary (IP) shocks within 1 AU should have oblique portions over much of their domain. Indeed, CME-driven shocks observed close to Earth are often oblique. However, it is well known that the standard diffusive shock acceleration mechanism, which relies on self-consistent wave generation via upstream propagating ions and their scattering, becomes increasingly inefficient with greater shock normal angle. Not only is a higher threshold energy required for the ions to leave the shock upstream, but also, approximately-parallel propagating waves are more quickly convected back into the shock, and the growth rate for waves propagating normal to the shock (the ones with the largest convective growth) decreases. As a result, typical, small-scale hybrid simulations of oblique shocks only show a dilute upstream beam, similar to what is often observed at the oblique Earth's bow shock - and no scattered, highly-energized ions. On the other hand, there are many "energetic storm particle" (ESP) events associated with oblique shocks that have significant fluxes of energetic ions. Recently, we have found that when run for a long time, our hybrid simulations (kinetic ions, electron fluid) show that the initial, weak beam is sufficient to generate compressive, steepening upstream waves. These waves are capable of disturbing the shock surface, resulting in an undulation that is propagating along the surface and growing in amplitude over time. The process is akin to that of the well-known reformation occurring at sufficiently strong quasi-parallel shocks. However, here the perturbations require at least two dimensions, show a strong spatial correlation, and travel along the shock surface. This process not only leads to enhanced ion acceleration, but also means that the shock characteristics are difficult to pinpoint, observationally: both the local jumps and the shock normal angle are highly variable. Shock undulation is also of interest to electron acceleration, since the undulated surface gives locally much larger shock normal angles and provides multiple mirroring and escape opportunities to accelerated electrons. We compare our simulations with a set of oblique shocks that we compiled from ACE observations, and discuss the results in the context of developing quantitative models of the flux and spectrum of energetic ions at IP shocks.

Krauss-Varban, D.; Li, Y.; Luhmann, J. G.

2006-12-01

344

Shock induced dissociation of polyethylene  

SciTech Connect

To identify the physical processes occurring on the Hugoniot, shock-recovery experiments were performed. Cylindrical recovery systems were used that enabled a wide range of single-shock Hugoniot states to be examined. Mass spectroscopy was used to examine the gaseous dissociation products. X-ray and TEM measurements were made to characterize the post-shock carbon structures. A dissociation product equation of state is presented to interpret the observed results. Polyethylene (PE) samples that were multiply shocked to their final states dissociated at much higher pressures than single-shocked samples. 5 refs., 2 figs., 1 tab.

Morris, C.E.; Loughran, E.D.; Mortensen, G.F.; Gray, G.T. III; Shaw, M.S.

1989-01-01

345

Shock train and pseudo-shock phenomena in internal gas flows  

Microsoft Academic Search

The interaction between a normal shock wave and a boundary layer along a wall surface in internal compressible flows causes a very complicated flow. When the shock is strong enough to separate the boundary layer, the shock is bifurcated and one or more shocks appear downstream of the bifurcated shock. A series of shocks thus formed, called “shock train”, is

Kazuyasu Matsuo; Yoshiaki Miyazato; Heuy-Dong Kim

1999-01-01

346

The Maine Music Box  

NSDL National Science Digital Library

Created through a collaboration between the University of Maine's Fogler Library and other Maine libraries, The Maine Music Box contains hundreds of digitized sheet music scores from five major collections. First-time visitors to the site will want to click on the "About Maine Music Box" project as a way of getting started. Here they can check out the "User Information" area, which contains helpful tips on viewing the music and how to best browse the entire database. Additionally, those with a penchant for technical details and information science in general can also learn in copious detail how the database was created for this project. From there, visitors can move straight away into the main collection. Visitors can browse the collection by music subject, sheet music cover art, or just type in their own keywords. One of the best ways to look over the collection is to browse around in such areas as "Instructional Violin", "Maine Collection" and "Parlor Salon Collection". It's also worth remarking that this site may inspire a sing-a-long, a campfire get-together, or a miniature Chautauqua.

347

Survey of interplanetary shock characteristics  

NASA Astrophysics Data System (ADS)

We report on a comparison of more than one hundred interplanetary shocks observed by both the Wind and ACE spacecraft. For each event, we use single spacecraft analysis methods such as the full Rankine-Hugoniot jump relations and the simpler velocity and magnetic coplanarity techniques to determine the shock orientation, speed, and assorted mach numbers and angles. We present a comparison of the properties of the shocks as a function of the separation between the spacecraft to determine the accuracy of the analysis methods and the non-planarity of IP shocks. The accuracy of the derived shock parameters and the non-planarity of the shock fronts are quantified by comparing the observed shock transit time between the spacecraft with predicted transit times calculated from the derived shock properties. The average timing errors for a given analysis method is the same using the Wind or ACE dataset; The Ranking-Hugoniot method performs best, with an RMS timing error of two minutes. We have studied the non-planarity of the shocks by comparing the implied radius of curvature determined by the difference between the two derived normals with the separation of the spacecraft. The variation is consistent with a five-degree error in shock direction and a typical radius of curvature of 0.1-0.3 AU. The shock parameters are made available through an online database (1). (1) http://space.mit.edu/home/jck/shockdb/shockdb.html

Kasper, J. C.; Lazarus, A. J.; Szabo, A.; Ogilvie, K. W.; Skoug, R.; Steinberg, J. T.; Smith, C.

2005-12-01

348

Shigella subverts the host recycling compartment to rupture its vacuole.  

PubMed

Shigella enters epithlial cells via internalization into a vacuole. Subsequent vacuolar membrane rupture allows bacterial escape into the cytosol for replication and cell-to-cell spread. Bacterial effectors such as IpgD, a PI(4,5)P2 phosphatase that generates PI(5)P and alters host actin, facilitate this internalization. Here, we identify host proteins involved in Shigella uptake and vacuolar membrane rupture by high-content siRNA screening and subsequently focus on Rab11, a constituent of the recycling compartment. Rab11-positive vesicles are recruited to the invasion site before vacuolar rupture, and Rab11 knockdown dramatically decreases vacuolar membrane rupture. Additionally, Rab11 recruitment is absent and vacuolar rupture is delayed in the ipgD mutant that does not dephosphorylate PI(4,5)P2 into PI(5)P. Ultrastructural analyses of Rab11-positive vesicles further reveal that ipgD mutant-containing vacuoles become confined in actin structures that likely contribute to delayed vacular rupture. These findings provide insight into the underlying molecular mechanism of vacuole progression and rupture during Shigella invasion. PMID:25299335

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

2014-10-01

349

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

350

Factors Controlling Stress Rupture of Fiber-Reinforced Ceramic Composites  

NASA Technical Reports Server (NTRS)

The successful application of fiber-reinforced ceramic matrix composites (CMC) depends strongly on maximizing material rupture life over a wide range of temperatures and applied stresses. The objective of this paper is to examine the various intrinsic and extrinsic factors that control the high-temperature stress rupture of CMC for stresses below and above those required for cracking of the 0 C plies (Regions I and II, respectively). Using creep-rupture results for a variety of ceramic fibers and rupture data for CMC reinforced by these fibers, it is shown that in those cases where the matrix carries little structural load, CMC rupture conditions can be predicted very well from the fiber behavior measured under the appropriate test environment. As such, one can then examine the intrinsic characteristics of the fibers in order to develop design guidelines for selecting fibers and fiber microstructures in order to maximize CMC rupture life. For those cases where the fiber interfacial coatings are unstable in the test environment, CMC lives are generally worse than those predicted by fiber behavior alone. For those cases where the matrix can support structural load, CMC life can even be greater provided matrix creep behavior is properly controlled. Thus the achievement of long CMC rupture life requires understanding and optimizing the behavior of all constituents in the proper manner.

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

1999-01-01

351

Experimental Plans for Subsystems of a Shock Wave Driven Gas Core Reactor  

NASA Technical Reports Server (NTRS)

This Contractor Report proposes a number of plans for experiments on subsystems of a shock wave driven pulsed magnetic induction gas core reactor (PMI-GCR, or PMD-GCR pulsed magnet driven gas core reactor). Computer models of shock generation and collision in a large-scale PMI-GCR shock tube have been performed. Based upon the simulation results a number of issues arose that can only be addressed adequately by capturing experimental data on high pressure (approx.1 atmosphere or greater) partial plasma shock wave effects in large bore shock tubes ( 10 cm radius). There are three main subsystems that are of immediate interest (for appraisal of the concept viability). These are (1) the shock generation in a high pressure gas using either a plasma thruster or pulsed high magnetic field, (2) collision of MHD or gas dynamic shocks, their interaction time, and collision pile-up region thickness, and (3) magnetic flux compression power generation (not included here).

Kazeminezhad, F.; Anghai, S.

2008-01-01

352

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

353

Implications of rupture complexity for hazard assessment and forecasting of local and regional tsunami  

NASA Astrophysics Data System (ADS)

Traditionally hazard assessment for tsunami does not take rupture complexity, i.e. the heterogeneity of the slip distribution across the earthquake rupture interface, into account. The authors have demonstrated that the potential extent of inundation will be significantly underestimated if rupture complexity is ignored. For local tsunami it has also been shown that for a target site a strict proportionality between earthquake moment magnitude and inundation extent does not exist. The main difficulty in including the effects of rupture complexity in Probabilistic Tsunami Hazard Assessment (PTHA) for local and regional tsunami lies in the fact that calculations to full inundation need to solve non-linear wave equations. These calculations are so computationally expensive that simulating a statistically significant number of scenarios becomes impractical. The hazard assessment process thus requires a de-aggregation procedure that can rely on simulations based on the linear wave equations alone, to identify scenarios significant enough to be considered for full inundation modelling. We correlate properties of the offshore wave field derived from linear simulations with the extent of inundation derived from non-linear tsunami simulations, allowing us to reduce non-linear calculations in our hazard assessment to a practical number. The effect of rupture complexity on the tsunami wave field is routinely considered in tsunami forecasting for distant and regional sources. Source models are inverted from DART buoy readings as soon as this information becomes available. However, depending on the location of the earthquake causing the tsunami, DART buoy information will not be provided immediately after the event, which poses a challenge to tsunami forecasting for local and regional sources. We propose a concept of tsunami forecasting for regional tsunami, which also provides probabilistic hazard assessment for the event in question. This approach considers rupture complexity and other uncertainties in the time period between detection of the tsunamigenic earthquake and the delivery of forecasts based on DART buoy information. It allows for more informed evacuation decision making during this period. This concept requires the calculation of multiple potential scenarios while the event unfolds. Thus, software that calculates the tsunami wave field in supra real-time (much faster than the physical manifestation of the tsunami) needs to be employed. For our study we have used COMCOT (development version, GNS Science) and the fast tsunami simulation program easyWave (kindly provided by Andrey Babeyko, GFZ Potsdam) and integrated both tools into a python based automation framework.

Müller, Christof; Power, William; Fraser, Stuart; Wang, Xiaoming; Ristau, John

2014-05-01

354

[Premature rupture of membranes: pathophysiology of neurological impact].  

PubMed

The premature rupture of membranes (PROM) is responsible for 30 % of the premature births because of a high risk of associated chorioamnionitis. PROM and the perinatal infection are recognized as 2 of the main risk factors of periventricular leukomalacia and white matter disease in very preterm neonates. Inflammation associated with PROM is likely to induce neuronal or glial cell death at a developmental stage of great vulnerability for the developing brain. Several mechanisms (release of cytokines, accumulation of free radicals, excitotoxicity, apoptosis...) account for this deleterious effect. The decision to actively extract a fetus subjected to a fetal inflammatory response syndrome should take account of the risks of a proved intrauterine infection for both the mother and the fetus and the risks for the neonate related to a very preterm birth per se. A reasonable attitude seems not to maintain a fetus in an undoubtful septic context in utero if a preterm birth in the very short term appears unevitable. Practically, no consensus gives a recommendation between aggressive or conservative management in case of PROM within 30 and 34 weeks'gestation. Expectant management seems to be indicated before 28 weeks'gestation and intentional delivery could be recommended beyond 34 weeks'gestation due to increased maternal risks compared to relatively low incidence of the complications of prematurity at this term. PMID:17939958

Baud, O; Fontaine, R H; Olivier, P; Maury, L; El Moussawi, F; Bauvin, I; Arsac, M; Hovhannisyan, S; Farnoux, C; Aujard, Y

2007-09-01

355

Cough and spontaneous rupture of a normal spleen.  

PubMed

Rupture of the spleen is a relatively common complication of trauma and many systemic disorders affecting the reticuloendothelial system, including infections and neoplasias. A rare subtype of rupture occurring spontaneously and arising from a normal spleen was recognized as a distinct clinicopathologic entity. The pathogenesis is debated in the absence of external trauma or predisposing disease. It has been reported in association with apparently trivial insults such as vomiting. We report a case of a patient with spontaneous rupture of a normal spleen. Interestingly, it was observed after severe coughing. PMID:16162801

Toubia, Nagib T; Tawk, Maroun M; Potts, Robyn M; Kinasewitz, Gary T

2005-09-01

356

TachoSil for postinfarction ventricular free wall rupture.  

PubMed

Despite a decline in the last three decades, postinfarction ventricular free wall rupture still complicates more than 3% of acute ST-elevation myocardial infarctions and remains a surgical challenge. TachoSil (Nycomed, Zurich, Switzerland) is an equine collagen patch coated with human fibrinogen and human thrombin, which has recently been used for haemostasis in cardiovascular surgery, but its potential usefulness in free wall rupture has not been reported. Initial clinical experience with an on-pump sutureless technique without cardioplegia, using wide TachoSil patching to achieve free wall rupture repair, has been described. PMID:22419793

Pocar, Marco; Passolunghi, Davide; Bregasi, Alda; Donatelli, Francesco

2012-06-01

357

TachoSil® for postinfarction ventricular free wall rupture  

PubMed Central

Despite a decline in the last three decades, postinfarction ventricular free wall rupture still complicates more than 3% of acute ST-elevation myocardial infarctions and remains a surgical challenge. TachoSil® (Nycomed, Zurich, Switzerland) is an equine collagen patch coated with human fibrinogen and human thrombin, which has recently been used for haemostasis in cardiovascular surgery, but its potential usefulness in free wall rupture has not been reported. Initial clinical experience with an on-pump sutureless technique without cardioplegia, using wide TachoSil® patching to achieve free wall rupture repair, has been described. PMID:22419793

Pocar, Marco; Passolunghi, Davide; Bregasi, Alda; Donatelli, Francesco

2012-01-01

358

Ruptured femoral pseudoaneurysm presenting as a lateral abdominal wall hematoma.  

PubMed

Lateral abdominal wall hematomas are rare. We describe a patient with a delayed rupture of a femoral artery pseudoaneurysm, who presented with such a hematoma. In contrast to other types of abdominal wall hematomas, which are often managed conservatively, a ruptured femoral artery pseudoaneurysm frequently requires emergent surgical intervention. Rupture of a pseudoaneurysm can be catastrophic. Due to the rising incidence of femoral artery pseudoaneurysms and shorter hospital stays, it is useful for the emergency physician to be familiar with the diagnosis and management of femoral artery pseudoaneurysms and their potentially life-threatening complications. PMID:16029823

Ma, Marek; Snook, Curtis P

2005-08-01

359

Rupture Propagation beyond Fault Discontinuities: Significance of Thermal Pressurization  

NASA Astrophysics Data System (ADS)

Effect of thermal pressurization (TP) on rupture processes over unconnected fault segments has not been investigated at all. In this study, we show that TP causes various rupture propagation beyond fault discontinuities by 3-D numerical simulations for spontaneous ruptures with TP. We put two vertical strike-slip square faults in a semi-infinite, homogenous, and elastic medium. The second fault (Fault 2) is parallel to the first one (Fault 1). We examine compressional and extensional cases with some values of stepover width. Both faults reach the free surface. The lengths of Faults 1 and 2 are 6 and 3 km, respectively. The numerical algorithm is based on the finite-difference method by Kase and Kuge (2001). Rupture is initiated in a small patch close to a side edge of Fault 1, and then proceeds spontaneously, governed by a slip-weakening law with the Coulomb failure criteria. The friction coefficients and initial stresses are uniform and the same on the two faults. On a fault with TP, we allow effective normal stress to vary with pore pressure change by the formulation of Bizzarri and Cocco (2006). We examine three cases; TP works on neither of the faults ('drain- drain'), on only Fault 2 ('drain-TP'), and on only Fault 1 ('TP-drain'). In the 'drain-drain' case, rupture jumps to Fault 2 near the free surface, and the rupture cannot jump when the stepover width is larger than a certain value. This observation is consistent with Harris and Day (1999) and Kase and Kuge (2001). In the 'drain- TP' case, TP on Fault 2 quickly accelerates propagation of small rupture triggered on Fault 2. In the 'TP- drain' case, the stress drop on Fault 1 is larger and off-fault stress changes drastically. Then, rupture is triggered sometimes near the free surface, as well as rupture triggered at the bottom, and sometimes at a deeper part. Due to these effects of TP, the maximum of stepover width that rupture can jump becomes larger. The effects of TP are observed in both extensional and compressional cases. Therefore, TP has a significant role on whether or not, and where rupture can jump from one fault to another. Moreover, our results imply that the existence and nature of fluid on faults may be diagnosed by comparing rupture jumps between our numerical simulations and real earthquakes.

Urata, Y.; Kuge, K.; Kase, Y.

2008-12-01

360

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

361

Successful treatment of a ruptured flow-related aneurysm in a patient with hemangioblastoma: Case report and review of literature  

PubMed Central

Background: No cerebral aneurysms on the feeder associated with hemangioblastomas that ruptured before resection have been reported. We report a patient with a ruptured flow-related aneurysm associated with cerebellar hemangioblastoma and a tumor feeder treated simultaneously by a single procedure of embolization using N-butyl cyanoacrylate before tumor removal. Case Description: A 36-year-old female with a cerebellar tumor was admitted to our institute. Four days later, she suffered a massive subarachnoid hemorrhage mainly in the posterior fossa. Left vertebral angiograms showed an aneurysm on the feeding artery, posterior inferior cerebellar artery. Both the aneurysm and its main feeder were simultaneously treated by a single procedure of embolization using N-butyl cyanoacrylate. Their complete obliteration was confirmed angiographically. Four days after the procedure, we removed the tumor and the embolized aneurysm. The pathological diagnosis was hemangioblastoma and flow-related ruptured aneurysm. Conclusion: Cerebral angiography should be performed to rule out vascular abnormalities such as cerebral aneurysms adjacent to the tumor in patients with hemangioblastoma who present with intracranial hemorrhage. We emphasize the usefulness of embolization with N-butyl cyanoacrylate for hemangioblastoma with ruptured feeder aneurysm, by which the aneurysm and the feeder could be simultaneously embolized.

Suzuki, Masanori; Umeoka, Katsuya; Kominami, Shushi; Morita, Akio

2014-01-01

362

Shock Acceleration in the Solar Corona  

NASA Astrophysics Data System (ADS)

In this thesis acceleration of energetic particles at collisionless shock waves in space plasmas is studied using numerical simulations, with an emphasis on physical conditions applicable to the solar corona. The thesis consists of four research articles and an introductory part that summarises the main findings reached in the articles and discusses them with respect to theory of diffusive shock acceleration and observations. This thesis gives a brief review of observational properties of solar energetic particles and discusses a few open questions that are currently under active research. For example, in a few large gradual solar energetic particle events the heavy ion abundance ratios and average charge states show characteristics at high energies that are typically associated with flare-accelerated particles, i.e. impulsive events. The role of flare-accelerated particles in these and other gradual events has been discussed a lot in the scientific community, and it has been questioned if and how the observed features can be explained in terms of diffusive shock acceleration at shock waves driven by coronal mass ejections. The most extreme solar energetic particle events are the so-called ground level enhancements where particle receive so high energies that they can penetrate all the way through Earth's atmosphere and increase radiation levels at the surface. It is not known what conditions are required for acceleration into GeV/nuc energies, and the presence of both very fast coronal mass ejections and X-class solar flares makes it difficult to determine what is the role of these two accelerators in ground level enhancements. The theory of diffusive shock acceleration is reviewed and its predictions discussed with respect to the observed particle characteristics. We discuss how shock waves can be modeled and describe in detail the numerical model developed by the author. The main part of this thesis consists of the four scientific articles that are based on results of the numerical shock acceleration model developed by the author. The novel feature of this model is that it can handle complex magnetic geometries which are found, for example, near active regions in the solar corona. We show that, according to our simulations, diffusive shock acceleration can explain the observed variations in abundance ratios and average charge states, provided that suitable seed particles and magnetic geometry are available for the acceleration process in the solar corona. We also derive an injection threshold for diffusive shock acceleration that agrees with our simulation results very well, and which is valid under weakly turbulent conditions. Finally, we show that diffusive shock acceleration can produce GeV/nuc energies under suitable coronal conditions, which include the presence of energetic seed particles, a favourable magnetic geometry, and an enhanced level of ambient turbulence.

Sandroos, Arto

2010-03-01

363

Radiative relativistic shock adiabate  

SciTech Connect

The influences of thermal radiation on the state equation of shock waves, derived in the previous paper [L. N. Tsintsadze, Phys. Plasmas {bold 2}, 4462 (1995)], are studied and a series of relations of thermodynamic quantities that hold for shock waves are derived. It is shown that the presence of radiation can strongly change the compressibility of the plasma. It is well known that for polytropic gases the compressibility cannot change more than four times the initial value in the case of nonrelativistic temperatures. The numerical calculations show that there are no such restrictions, when the radiation energy exceeds the kinetic energy of the plasma. The ultrarelativistic temperature range is also covered in our numerical calculations. Also studied are the influences of the radiation on the PT and the TV diagrams. A significant modification due to radiation is found in every case studied. {copyright} {ital 1997 American Institute of Physics.}

Tsintsadze, L.N.; Nishikawa, K. [Faculty of Science, Hiroshima University, Higashihiroshima-City 1739 (Japan)] [Faculty of Science, Hiroshima University, Higashihiroshima-City 1739 (Japan)

1997-03-01

364

SUPERDIFFUSIVE SHOCK ACCELERATION  

SciTech Connect

The theory of diffusive shock acceleration is extended to the case of superdiffusive transport, i.e., when the mean square deviation grows proportionally to t{sup {alpha}}, with {alpha} > 1. Superdiffusion can be described by a statistical process called Levy random walk, in which the propagator is not a Gaussian but it exhibits power-law tails. By using the propagator appropriate for Levy random walk, it is found that the indices of energy spectra of particles are harder than those obtained where a normal diffusion is envisaged, with the spectral index decreasing with the increase of {alpha}. A new scaling for the acceleration time is also found, allowing substantially shorter times than in the case of normal diffusion. Within this framework we can explain a number of observations of flat spectra in various astrophysical and heliospheric contexts, for instance, for the Crab Nebula and the termination shock of the solar wind.

Perri, S.; Zimbardo, G. [Dipartimento di Fisica, Universita della Calabria, Ponte P. Bucci Cubo 31C, I-87036 Rende (Italy)

2012-05-10

365

The main cubioid  

NASA Astrophysics Data System (ADS)

The connectedness locus in the parameter space of quadratic polynomials is called the Mandelbrot set. A good combinatorial model of this set is due to Thurston. By definition, the principal hyperbolic domain of the Mandelbrot set consists of parameter values, for which the corresponding quadratic polynomials have an attracting fixed point. The closure of the principal hyperbolic domain of the Mandelbrot set is called the main cardioid. Its topology is completely described by Thurston's model. Less is known about the connectedness locus in the parameter space of cubic polynomials. In this paper, we discuss cubic analogues of the main cardioid and establish relationships between them.

Blokh, Alexander; Oversteegen, Lex; Ptacek, Ross; Timorin, Vladlen

2014-08-01

366

Shock compression of wüstite  

Microsoft Academic Search

Hugoniot compression curve of wüstite (Fe1-xO) was studied up to 120 GPa using a double-stage light-gas gun. Pore-free polycrystalline wütite was grown by the floating zone method and platelet specimens, typically 10×14×2 mm3, were prepared. The inclined mirror method was adopted to record the shock compression state and both the impedance matching solution and the free surface approximation were used

T. Yagi; K. Fukuoka; H. Takei; Y. Syono

1988-01-01

367

Shock Compression of Feldspars  

Microsoft Academic Search

Hugoniot data for oligoclase and microcline to 670 and 580 kb and release adiabat data for oligoclase were obtained by means of the inclined mirror and immersed-foil-reflected-light techniques, respectively. Oligoclase and microcline have Hugoniot elastic limits in the range of 40-55 and 80-85 kb. These limits increase slightly with increasing driving shock pressure. Above the elastic limit, extending to 300

Thomas J. Ahrens; C. F. Petersen; J. T. Rosenberg

1969-01-01

368

Shock Therapy with Seawater  

NSDL National Science Digital Library

This radio broadcast describes a technique called 'salinity shock' which is being used to kill plants and animals that ride in ballast water on ships. Oceangoing ships are now dumping their freshwater ballast at sea and taking on a new load of saltwater to kill and flush out stowaway organisms. The clip is 2 minutes in length and may be downloaded in MP3 format.

Hoops, Richard

2012-01-09

369

[Infusion treatment in shock].  

PubMed

Nowadays, above all dextran, gelatin and starch solutions are available for the infusion theraphy of the various forms of shock. The application of these volume substitutes must be strictly controlled to avoid in particular cardial and pulmonal commplications. Blood transfusion combined with a volume substitute should only be applied in cases of heavy loss of blood. The treatment of metabolic acidose which usually occurs simultaneously is carried out with an alkaline solution. PMID:1344

Esser, H

1975-12-01

370

Simplified approach for design of raft foundations against fault rupture. Part I: free-field  

NASA Astrophysics Data System (ADS)

Over the past few decades, earthquake engineering research mainly focused on the effects of strong seismic shaking. After the 1999 earthquakes in Turkey and Taiwan, and thanks to numerous cases where fault rupture caused substantial damage to structures, the importance of faulting-induced deformation has re-emerged. This paper, along with its companion (Part II), exploits parametric results of finite element analyses and centrifuge model testing in developing a four-step semi-analytical approach for analysis of dip-slip (normal and thrust) fault rupture propagation through sand, its emergence on the ground surface, and its interaction with raft foundations. The present paper (Part I) focuses on the effects of faulting in the absence of a structure (i.e., in the free-field). The semi-analytical approach comprises two-steps: the first deals with the rupture path and the estimation of the location of fault outcropping, and the second with the tectonically-induced displacement profile at the ground surface. In both cases, simple mechanical analogues are used to derive simplified semi-analytical expressions. Centrifuge model test data, in combination with parametric results from nonlinear finite element analyses, are utilized for model calibration. The derived semi-analytical expressions are shown to compare reasonably well with more rigorous experimental and theoretical data, thus providing a useful tool for a first estimation of near-fault seismic hazard.

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

2008-06-01

371

Shear rupture of a directionally solidified eutectic gamma/gamma prime - alpha (Mo) alloy  

NASA Technical Reports Server (NTRS)

Directionally solidified Mo alloys are evaluated to determine the shear rupture strength and to possibly improve it by microstructural and heat treatment variations. Bars of the alloy containing nominally 5.7% Al and 33.5% Mo by weight with balance Ni were directionally solidified at rates between 10 and 100 mm per hour in furnaces with thermal gradients at the liquid-solid interface of 250 or 100 C per cm. A limited number of longitudinal shear rupture tests were conducted at 760 C and 207 MPa in the as - solidified and in several heat treated conditions. It is shown that shear rupture failures are partly transgranular and that resistance to failure is prompted by good fiber alignment and a matrix structure consisting mainly of gamma prime. Well aligned as - solidified specimens sustained the shear stress for an average of 81 hours. A simulated coating heat treatment appeared to increase the transformation of gamma to gamma prime and raised the average shear life of aligned specimens to 111 hours. However, heat treatments at 1245 C and especially at 1190 C appeared to be detrimental by causing partial solutioning of the gamma prime, and reducing lives to 47 and 10 hours, respectively.

Harf, F. H.

1978-01-01

372

MAINE SCHOOLS AND LIBRARIES  

EPA Science Inventory

SCHLIB shows point locations of libraries and educational institutions in Maine at 1:24,000 scale. Colleges, universities, technical colleges, high schools, middle schools, elementary schools, kindergarten/sub-primary and other special schools are included. The data was developed...

373

Maine Dance Curriculum Guide.  

ERIC Educational Resources Information Center

This curriculum guide is designed to support those in Maine who wish to establish or enhance dance education in any educational areas and at elementary or secondary levels. A preface describes the state's dance heritage. An introduction argues for the importance of dance education. The next section addresses pedagogy and explains how to create and…

Grindel, Susan; And Others

374

COLDSPRINGCREEK MAIN STREET WEST  

E-print Network

.................................... 43 David Braley Athletic Centre.... 54 Divinity College............................ 17 Dramatic Arts MAIN STREET WEST COLLEGE CRESCENT COOTESDRIVE WESTAWAY ROAD SCHOLAR'S ROAD STEARN DRIVE Entrance Pay Stations Short Term Parking - Pay and Display Campus Shuttle Bus Service Go Bus Stop A-Q CAMPUS

Thompson, Michael

375

COLDSPRINGCREEK MAIN STREET WEST  

E-print Network

....................................43 David Braley Athletic Centre ....54 Divinity College............................17 Dramatic Arts 37 MAIN STREET WEST COLLEGE CRESCENT COOTESDRIVE WESTAWAY ROAD SCHOLAR'S ROAD STEARN DRIVE EntranceCampus LEGEND McMaster University Entrance Security and Parking Services Parking Lot Location Pay Stations Short

Haykin, Simon

376

Main Course Beef Lasagne  

E-print Network

with lemon and free range egg mayonnaise Mediterranean Quorn and Garlic Pie A ragu of roasted Mediterranean vegetables and Quorn topped with garlic bread slices Served with Sautéed New Potatoes or Penne Pasta Sweet Corn & Garlic Bread Salad Bar Should you wish to have salad as your main meal please see the choice

Bristol, University of

377

The Bear River Fault Zone, Wyoming and Utah: Complex Ruptures on a Young Normal Fault  

NASA Astrophysics Data System (ADS)

The Bear River fault zone (BRFZ), a set of normal fault scarps located in the Rocky Mountains at the eastern margin of Basin and Range extension, is a rare example of a nascent surface-rupturing fault. Paleoseismic investigations (West, 1994; this study) indicate that the entire neotectonic history of the BRFZ may consist of two large surface-faulting events in the late Holocene. We have estimated a maximum per-event vertical displacement of 6-6.5 m at the south end of the fault where it abuts the north flank of the east-west-trending Uinta Mountains. However, large hanging-wall depressions resulting from back rotation, which front scarps that locally exceed 15 m in height, are prevalent along the main trace, obscuring the net displacement and its along-strike distribution. The modest length (~35 km) of the BRFZ indicates ruptures with a large displacement-to-length ratio, which implies earthquakes with a high static stress drop. The BRFZ is one of several immature (low cumulative displacement) normal faults in the Rocky Mountain region that appear to produce high-stress drop earthquakes. West (1992) interpreted the BRFZ as an extensionally reactivated ramp of the late Cretaceous-early Tertiary Hogsback thrust. LiDAR data on the southern section of the fault and Google Earth imagery show that these young ruptures are more extensive than currently mapped, with newly identified large (>10m) antithetic scarps and footwall graben. The scarps of the BRFZ extend across a 2.5-5.0 km-wide zone, making this the widest and most complex Holocene surface rupture in the Intermountain West. The broad distribution of Late Holocene scarps is consistent with reactivation of shallow bedrock structures but the overall geometry of the BRFZ at depth and its extent into the seismogenic zone are uncertain.

Schwartz, D. P.; Hecker, S.; Haproff, P.; Beukelman, G.; Erickson, B.

2012-12-01

378

A mRNA-based thermosensor controls expression of rhizobial heat shock genes  

Microsoft Academic Search

Expression of several heat shock operons, mainly coding for small heat shock proteins, is under the control of ROSE (repression of heat shock gene expression) in various rhizobial species. This nega- tively cis-acting element confers temperature control by preventing expression at physiological tempera- tures. We provide evidence that ROSE-mediated regulation occurs at the post-transcriptional level. A detailed mutational analysis of

Andreas Nocker; Thomas Hausherr; Sylvia Balsiger; Nila-Pia Krstulovic; Hauke Hennecke; Franz Narberhaus

2001-01-01

379

Extracellular Matrix Dynamics and Fetal Membrane Rupture  

PubMed Central

The extracellular matrix (ECM) plays an important role in determining cell and organ function: (1) it is an organizing substrate that provides tissue tensile strength; (2) it anchors cells and influences cell morphology and function via interaction with cell surface receptors; and (3) it is a reservoir for growth factors. Alterations in the content and the composition of the ECM determine its physical and biological properties, including strength and susceptibility to degradation. The ECM components themselves also harbor cryptic matrikines, which when exposed by conformational change or proteolysis have potent effects on cell function, including stimulating the production of cytokines and matrix metalloproteinases (MMPs). Collectively, these properties of the ECM reflect a dynamic tissue component that influences both tissue form and function. This review illustrates how defects in ECM synthesis and metabolism and the physiological process of ECM turnover contribute to changes in the fetal membranes that precede normal parturition and contribute to the pathological events leading to preterm premature rupture of membranes (PPROM). PMID:22267536

Strauss,, Jerome F.

2013-01-01

380

BIOCHEMICAL STUDIES ON SHOCK  

PubMed Central

1. In a series of rats subjected to hemorrhage and shock a high negative correlation was found between the portal and peripheral venous oxygen saturations and the arterial blood pressure on the one hand, and the blood amino nitrogen levels on the other, and a high positive correlation between the portal and the peripheral oxygen saturations and between each of these and the blood pressure. 2. In five cats subjected to hemorrhage and shock the rise in plasma amino nitrogen and the fall in peripheral and portal venous oxygen saturations were confirmed. Further it was shown that the hepatic vein oxygen saturation falls early in shock while the arterial oxygen saturation showed no alteration except terminally, when it may fall also. 3. Ligation of the hepatic artery in rats did not affect the liver's ability to deaminate amino acids. Hemorrhage in a series of hepatic artery ligated rats did not produce any greater rise in the blood amino nitrogen than a similar hemorrhage in normal rats. The hepatic artery probably cannot compensate to any degree for the decrease in portal blood flow in shock. 4. An operation was devised whereby the viscera and portal circulation of the rat were eliminated and the liver maintained only on its arterial circulation. The ability of such a liver to metabolize amino acids was found to be less than either the normal or the hepatic artery ligated liver and to have very little reserve. 5. On complete occlusion of the circulation to the rat liver this organ was found to resist anoxia up to 45 minutes. With further anoxia irreversible damage to this organ's ability to handle amino acids occurred. 6. It is concluded that the blood amino nitrogen rise during shock results from an increased breakdown of protein in the peripheral tissues, the products of which accumulate either because they do not circulate through the liver at a sufficiently rapid rate or because with continued anoxia intrinsic damage may occur to the hepatic parenchyma so that it cannot dispose of amino acids. PMID:19871356

Engel, Frank L.; Harrison, Helen C.; Long, C. N. H.

1944-01-01

381

Shock structuring due to fabrication joints in targets  

NASA Astrophysics Data System (ADS)

The use of copper-doped beryllium ablators on National Ignition Facility [J. A. Paisner et al., Laser Focus World 30, 75 (1994)] targets, in place of plastic, can require the bonding together of hemispheres with a joint of differing composition. Indirect drive experiments have been conducted on the Nova laser [J. L. Emmet, W. F. Krupke, and J. B. Trenholme, Sov. J. Quantum Electron. 13, 1 (1983)], and the resulting shock structuring compared with code simulations. It is concluded that one of the available codes, the RAGE code [R. M. Baltrusaitis et al., Phys. Fluids 8, 2471 (1996)] provides useful insight into the effect of joints. This code is then employed to obtain a physical picture of the shock front nonuniformity in terms of a secondary rarefaction and an oblique shock interacting with the main shock that propagates in the absence of the joint. A simple analysis reinforces this picture.

Goldman, S. R.; Caldwell, S. E.; Wilke, M. D.; Wilson, D. C.; Barnes, Cris W.; Hsing, W. W.; Delamater, N. D.; Schappert, G. T.; Grove, J. W.; Lindman, E. L.; Wallace, J. M.; Weaver, R. P.; Dunne, A. M.; Edwards, M. J.; Graham, P.; Thomas, B. R.

1999-08-01

382

Outflows, Jets and Shocks in the Orion Nebula  

NASA Technical Reports Server (NTRS)

The rich young cluster of stars associated with the Orion Nebula provides a unique laboratory for the study of plasma phenomena. We see five types of flows and shocks. Photoablation outflow from the proplyds nearest theta (exp 1) Ori C form nearly stationary shocks with the high velocity wind from that star. Microjets, with scales of less than 10 (exp 4) AU, are seen around some 20 low mass stars. Isolated jets, with high velocities and scales of about, 104 AU, are less numerous but common. One also sees the shocks formed when these jets impinge on the ionized nebular gas and the neutral gas in the foreground lid. The final type of object is the stationary shock formed by the interaction from the stellar wind that arises during disk formation with the ambient, gas flowing away from the main body of the nebula.

ODell, C. R.; Bally, John

2000-01-01

383

Dynamic rupture along bimaterial interfaces in 3D  

NASA Astrophysics Data System (ADS)

We perform numerical simulations of dynamic rupture propagation on a plane in a model consisting of two different elastic half spaces connected via a planar frictional interface governed by regularized Coulomb friction. Therefore, ruptures in this study are purely driven by the presence of a material contrast. Ruptures are nucleated on the fault using a circular symmetric expanding increase of pore-pressure in a limited source region. We show how a wrinkle-like rupture pulse can mature also in the 3D case where we have a mixing of in-plane and anti-plane modes, the instability specific of a bimaterial interface acting only for the in-plane mode. The pulse develops inside a cone-shaped region with its axis aligned with the direction of displacement in the softer material, its tip being at the nucleation region.

Brietzke, G. B.; Cochard, A.; Igel, H.

2007-06-01

384

Multi-Canister overpack necessity of the rupture disk  

SciTech Connect

The Multi-Canister Overpack (MCO) rupture disk precludes the MCO from pressurization above the design limit during transport from the K Basins to the Cold Vacuum Drying (CVD) Facility and prior to connection of the CVD process piping. Removal of the rupture disk from the MCO design would: (a) result in unacceptable dose consequences in the event a thermal runaway accident occurred; (b) increase residual risk; and (c) remove a degree of specificity from the dose calculations. The potential cost savings of removing the rupture disk from the MCO design is offset by the cost of design modifications, changes to hazard analyses and safety analyses, and changes to existing documentation. Retaining the rupture disk mitigates the consequences of MCO overpressurization, and considering the overall economic impacts to the SNF Project, is the most cost effective approach.

SMITH, K.E.

1998-11-03

385

Arterial helium embolism from a ruptured intraaortic balloon.  

PubMed

A 67-year-old man sustained a sudden global neurological deficit immediately following rupture of an intraaortic balloon catheter. Considerable improvement in his neurological function occurred during and after three hyperbaric oxygen treatments. PMID:3196106

Frederiksen, J W; Smith, J; Brown, P; Zinetti, C

1988-12-01

386

Controls on earthquake rupture and triggering mechanisms in subduction zones  

E-print Network

Large earthquake rupture and triggering mechanisms that drive seismicity in subduction zones are investigated in this thesis using a combination of earthquake observations, statistical and physical modeling. A comparison ...

Llenos, Andrea Lesley

2010-01-01

387

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. PMID:24149615

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

2009-01-01

388

Magnetic ramp scale at supercritical perpendicular collisionless shocks: Full particle electromagnetic simulations  

SciTech Connect

Supercritical perpendicular collisionless shocks are known to exhibit foot, ramp, and overshoot structures. The shock ramp structure is in a smaller scale in contrast to other microstructures (foot and overshoot) within the shock front. One-dimensional full particle simulations of strictly perpendicular shocks over wide ranges of ion beta ?{sub i}, Alfvén Mach number M{sub A}, and ion-to-electron mass ratio m{sub i}/m{sub e} are presented to investigate the impact of plasma parameters on the shock ramp scale. Main results are (1) the ramp scale can be as small as several electron inertial length. (2) The simulations suggest that in a regime below the critical ion beta value, the shock front undergoes a periodic self-reformation and the shock ramp scale is time-varying. At higher ion beta values, the shock front self-reformation is smeared. At still higher ion beta value, the motion of reflected ions is quite diffuse so that they can lead to a quasi-steady shock ramp. Throughout the above three conditions, the shock ramp thickness increases with ?{sub i}. (3) The increase (decrease) in Mach number and the decrease (increase) in the beta value have almost equivalent impact on the state (i.e., stationary or nonstationary) of the shock ramp. Both of front and ramp thicknesses are increased with M{sub A}.

Yang, Zhongwei [State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing 100080 (China) [State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing 100080 (China); SOA Key Laboratory for Polar Science, Polar Research Institute of China, Shanghai, 200136 (China); Lu, Quanming; Gao, Xinliang; Huang, Can [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Science, University of Science and Technology of China, Hefei 230026 (China)] [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Science, University of Science and Technology of China, Hefei 230026 (China); Yang, Huigen; Hu, Hongqiao; Han, Desheng [SOA Key Laboratory for Polar Science, Polar Research Institute of China, Shanghai, 200136 (China)] [SOA Key Laboratory for Polar Science, Polar Research Institute of China, Shanghai, 200136 (China); Liu, Ying [State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing 100080 (China)] [State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing 100080 (China)

2013-09-15

389

Lateral approach to laparoscopic repair of left diaphragmatic ruptures  

Microsoft Academic Search

Video-assisted repairs of traumatic diaphragmatic ruptures have been described where thoracoscopy or laparoscopy in the supine\\u000a position were used. This study aims to validate a new lateral laparoscopic approach for left diaphragmatic repairs. Six consecutive\\u000a patients were operated on for left diaphragmatic rupture using a lateral approach (Gagner’s position). A series of 362 consecutive\\u000a patients presenting with abdominal or thoracic

Pierre Goudet; Nicolas Cheynel; Loïc Ferrand; Frédérique Peschaud; Jean-Philippe Steinmetz; Bernard Letourneau; Jean-Paul Isnardon; Marie-Thérèse Noirot; Laurencia Poli; Marc Freysz; Patrick Cougard

2001-01-01

390

Iliopsoas hematoma due to muscular rupture following defibrillation.  

PubMed

We describe a 62 year old patient who presented with acute anterior ischemia and subsequently developed an iliopsoas hematoma. The patient was treated surgically due to rapid progression and femoral neuropathy, and the iliopsoas muscle rupture was diagnosed intraoperatively. The rupture was related to the external electrical defibrillation the patient had on admission. This was a rare case, and we hope the report would help to raise physicians' awareness regarding this complication and treatment. PMID:24347218

Jahollari, Artan; Cavolli, Raif; Tavlasoglu, Murat; Sallahu, Ferat; Muriqi, Shkelzen

2013-11-01

391

Successful patching of iatrogenic rupture of the fetal membranes.  

PubMed

Rupture of the fetal membranes is a common, but potentially serious complication of invasive fetal procedures. Quintero described a technique to seal the fetal membrane defect by means of a bloodpatch, usually called 'amniopatch' in this application. The successful use in two consecutive patients with ruptured membranes after a fetoscopic intervention at respectively 17 and 22 weeks' gestational age is described, together with a literature review of published experience. PMID:15028428

Lewi, L; Van Schoubroeck, D; Van Ranst, M; Bries, G; Emonds, M-P; Arabin, B; Welch, R; Deprest, J

2004-04-01

392

Macrophage Activation in Atherosclerosis: Pathogenesis and Pharmacology of Plaque Rupture  

Microsoft Academic Search

Atherosclerosis is still an important disease. It accounts for 39% of deaths in the U.K. and 12 million U.S citizens have atherosclerosis-associated disease. Atherosclerosis may exert clinical effects by slow narrowing, producing stable angina or dramatic rupture, producing acute coronary syndromes such as unstable angina or myocardial infarction and death. Macrophages are abundant in ruptured atherosclerotic plaques. Macrophages are innate

J. J. Boyle

2005-01-01

393

A support-operator method for 3-D rupture dynamics  

Microsoft Academic Search

We present a numerical method to simulate spontaneous shear crack propagation within a heterogeneous, 3-D, viscoelastic medium. Wave motions are computed on a logically rectangular hexahedral mesh, using the generalized finite-difference method of Support Operators (SOM). This approach enables modelling of non-planar surfaces and non-planar fault ruptures. Our implementation, the Support Operator Rupture Dynamics (SORD) code, is highly scalable, enabling

Geoffrey P. Ely; Steven M. Day; Jean-Bernard Minster

2009-01-01

394

Shock attenuating apparatus and method  

SciTech Connect

This patent describes an apparatus for attenuating a shock in a tool string within a well, comprising a body in extensible under tension loading. It comprises means for connecting the body into the tool string; and undergoing plastic deformation in response to an explosive impact load for serially dissipating energy of a shock wave propagated in the body in response to the explosion impact load wherein the means for undergoing deformation and dissipating energy includes a wall of the body wherein a plurality of indentations are defined. This patent also describes a method of attenuating shock from an explosion in a well. It comprises lowering into the well an explosive connected to a shock attenuating member; detonating the explosive whereby an impact load with a shock wave is generated; and collapsing without severing the member in response to the impact load and dissipating energy of the shock wave from a plurality of surfaces of the member.

Navarette, M.; Walker, J.L.

1992-06-02

395

Grain Destruction in Interstellar Shocks  

E-print Network

Interstellar shock waves can erode and destroy grains present in the shocked gas, primarily as the result of sputtering and grain-grain collisions. Uncertainties in current estimates of sputtering yields are reviewed. Results are presented for the simple case of sputtering of fast grains being stopped in cold gas. An upper limit is derived for sputtering of refractory grains in C-type MHD shocks: shock speeds $v_s \\gtrsim 50 \\kms$ are required for return of more than 30\\% of the silicate to the gas phase. Sputtering can also be important for removing molecular ice mantles from grains in two-fluid MHD shock waves in molecular gas. Recent estimates of refractory grain lifetimes against destruction in shock waves are summarized, and the implications of these short lifetimes are discussed.

B. T. Draine

1995-08-16

396

Maine Humanities Council  

NSDL National Science Digital Library

Formed as a private nonprofit organization, the Maine Humanities Council (MHC) "promotes strong communities and informed citizens by providing Mainers with opportunities to explore the power and pleasure of ideas." Their work is supported by volunteer board members, and their projects include programs to promote reading and writing, guest lectures around the state, and online newsletters and discussion groups. In the "Programs" area, visitors can learn about these programs, and educators can check out the resources created especially for them. The "Connections" area contains links to their thoughtful blog, their "Humanities on Demand" podcasts, and their periodic newsletter "Synapse", which deals with medicine and literature. The podcasts are quite fun, and they include "Franco-American Women's Words in Maine" and a talk by Professor Dianne Sadoff of Rutgers University on Middlemarch, by George Eliot.

397

Stars main sequence  

NSDL National Science Digital Library

What happens during most of a star's life? This activity page, part of an interactive laboratory series for grades 8-12, introduces students to the main sequence phase of a star's existence. This phase is where a star lives out the majority of its life. In an interactive lab activity, students predict the length of the main sequence for four different stars. The predictions can be printed for later evaluation. Students view diagrams that compare the size and color of stars to human lives, and equilibrium within a star is stressed. Finally, students choose between two hypotheses about the length of life of a star. Students write a one- to three-sentence explanation for their hypotheses. The correct answer is provided. Copyright 2005 Eisenhower National Clearinghouse

University of Utah. Astrophysics Science Project Integrating Research and Education (ASPIRE)

2003-01-01

398

COBRA Main Engine Project  

NASA Technical Reports Server (NTRS)

The COBRA (CO-Optimized Booster for Reusable Applications) project include the following: 1. COBRA main engine project team. 2. COBRA and RLX cycles selected. 3. COBRA proto-type engine approach enables mission success. 4. COBRA provides quick, low cost demo of cycle and technologies. 5. COBRA cycle I risk reduction supports. 6. Achieving engine safety. 6. RLX cycle I risk reduction supports. 7. Flight qualification. 9. Life extension engine testing.

Snoddy, Jim; Sides, Steve; Lyles, Garry M. (Technical Monitor)

2002-01-01

399

Estimation of wall properties and wall strength of aortic aneurysms using modern imaging techniques. One more step towards a patient-specific assessment of aneurysm rupture risk.  

PubMed

Abdominal aortic aneurysmal disease is a major health problem with rupture representing its main complication accompanied by great mortality. Elective repair is currently performed with mortality rates <3%, based upon size or expansion rate, with a recommended threshold of 5.5 cm maximum diameter or >1cm/year enlargement. It is well established that even small AAAs without indication for surgical repair can experience rupture with catastrophic outcomes whereas larger aneurysms often remain intact for a long period. It is recognized, therefore, that the currently used, maximum diameter criterion can not accurately predict AAAs evolution. There is increasing interest in the role of patient-specific biomechanical profiling of AAA development and rupture. Biomechanically, rupture of a vessel occurs when intravascular forces exceed vessel wall structural endurance. Peak Wall Stress (PWS) has been previously shown to better identify AAAs prone to rupture than maximum diameter, but currently stress analysis takes into account several assumptions that influence results to a large extent and limit their use. Moreover stress represents only one of two determinants of rupture risk according to the biomechanical perspective. Wall strength and mechanical properties on the other hand cannot be assessed in vivo but only ex vivo through mechanical studies with mean values of these parameters taken into account for rupture risk estimations. New possibilities in the field of aortic imaging offer promising tools for the validation and advancement of stress analysis and the in vivo evaluation of AAAs' wall properties and wall strength. Documentation of aortic wall motion during cardiac cycle is now feasible through ECG-gated multi-detector CT imaging offering new possibilities towards an individualized method for rupture risk and expansion-rate predictions based on data acquired in vivo. PMID:23714223

Kontopodis, Nikolaos; Georgakarakos, Efstratios; Metaxa, Eleni; Pagonidis, Konstantinos; Papaharilaou, Yannis; Ioannou, Christos V

2013-08-01

400

Short term creep rupture predictions for tantalum alloy T-111  

NASA Astrophysics Data System (ADS)

A knowledge of the short term creep rupture behavior of Tantalum alloy T-111 is necessary to predict device integrity in the heat source section of Radioisotope Thermoelectric Generators (RTGs) at the end of service life, in the event of a fuel fire. High pressures exist in RTGs near the end of service life, these are caused by gas generation resulting from radioactive decay of the nuclear fuel. The internal pressure exerts a significant hoop stress on the T-111 alloy structural containment member. This paper analyses the short term creep behavior (rupture times up to ˜2×103 hrs.) of cold worked (CW) T-111 alloy, using the existing data of Stephenson (1967). Corellations for the time to rupture, time to 1% strain and minimum creep rate have been obtained from this data using multivariable linear regression analysis. These results are compared to other short term rupture data for T-111 alloy. Finally, at the stress/temperature levels relevant to the RTG fuel fire scenario near the end of service life, the rupture time correlation for T-111 alloy predicts a rupture time of approximately 100 hrs.

Stephens, John J.

1991-01-01

401

Dynamic rupture modeling with laboratory-derived constitutive relations  

USGS Publications Warehouse

A laboratory-derived state variable friction constitutive relation is used in the numerical simulation of the dynamic growth of an in-plane or mode II shear crack. According to this formulation, originally presented by J.H. Dieterich, frictional resistance varies with the logarithm of the slip rate and with the logarithm of the frictional state variable as identified by A.L. Ruina. Under conditions of steady sliding, the state variable is proportional to (slip rate)-1. Following suddenly introduced increases in slip rate, the rate and state dependencies combine to produce behavior which resembles slip weakening. When rupture nucleation is artificially forced at fixed rupture velocity, rupture models calculated with the state variable friction in a uniformly distributed initial stress field closely resemble earlier rupture models calculated with a slip weakening fault constitutive relation. Model calculations suggest that dynamic rupture following a state variable friction relation is similar to that following a simpler fault slip weakening law. However, when modeling the full cycle of fault motions, rate-dependent frictional responses included in the state variable formulation are important at low slip rates associated with rupture nucleation. -from Author

Okubo, P.G.

1989-01-01

402

Shear rupture under constant normal stiffness boundary conditions  

NASA Astrophysics Data System (ADS)

A grain based Distinct Element Method and its embedded Grain Based Method are used to simulate the fracturing processes leading to shear rupture zone creation in a calibrated massive (non-jointed) brittle rock specimen deformed in direct shear under constant normal stiffness boundary conditions. Under these boundary conditions, shear rupture zone creation relative to the shear stress versus applied horizontal displacement (load-displacement) curve occurs pre-peak, before the maximum peak shear strength is reached. This is found to be the result of a normal stress feedback process caused by the imposed shear displacement which couples increases in normal stress, due to rupture zone dilation, with shear stress, producing a complex normal-shear stress-path that reaches and then follows the rock's yield (strength) envelope. While the yield envelope is followed, the shear strength increases further and shear stress oscillations (repeated stress drops followed by re-strengthening periods) in the load-displacement curves occur due to fracture creation as the rupture zone geometry smoothens. Once the maximum peak strength is reached (after a series of shear stress oscillations) the largest stress drops occur as the ultimate or residual shear strength is approached. The simulation results provide insight into the fracturing process during rupture zone creation and improve the understanding of the shear stress versus applied horizontal displacement response, as well as the stick-slip behaviour of shear rupture zones that are being created under constant normal stiffness boundary conditions.

Bewick, R. P.; Kaiser, P. K.; Bawden, W. F.

2014-11-01

403

The temporal distribution of seismic radiation during deep earthquake rupture  

USGS Publications Warehouse

The time history of energy release during earthquakes illuminates the process of failure, which remains enigmatic for events deeper than about 100 kilometers. Stacks of teleseismic records from regional arrays for 122 intermediate (depths of 100 to 350 kilometers) and deep (depths of 350 to 700 kilometers) earthquakes show that the temporal pattern of short-period seismic radiation has a systematic variation with depth. On average, for intermediate depth events more radiation is released toward the beginning of the rupture than near the end, whereas for deep events radiation is released symmetrically over the duration of the event, with an abrupt beginning and end of rupture. These findings suggest a variation in the style of rupture related to decreasing fault heterogeneity with depth.The time history of energy release during earthquakes illuminates the process of failure, which remains enigmatic for events deeper than about 100 kilometers. Stacks of teleseismic records from regional arrays for 122 intermediate (depths of 100 to 350 kilometers) and deep (depths of 350 to 700 kilometers) earthquakes show that the temporal pattern of short-period seismic radiation has a systematic variation with depth. On average, for intermediate depth events more radiation is released toward the beginning of the rupture than near the end, whereas for deep events radiation is released symmetrically over the duration of the event, with an abrupt beginning and end of rupture. These findings suggest a variation in the style of rupture related to decreasing fault heterogeneity with depth.

Houston, H.; Vidale, J.E.

1994-01-01

404

Flexible Multi-Shock Shield  

NASA Technical Reports Server (NTRS)

Flexible multi-shock shield system and method are disclosed for defending against hypervelocity particles. The flexible multi-shock shield system and method may include a number of flexible bumpers or shield layers spaced apart by one or more resilient support layers, all of which may be encapsulated in a protective cover. Fasteners associated with the protective cover allow the flexible multi-shock shield to be secured to the surface of a structure to be protected.

Christiansen, Eric L. (Inventor); Crews, Jeanne L. (Inventor)

2005-01-01

405

Initial ISEE magnetometer results: Shock observation  

Microsoft Academic Search

ISEE-1 and -2 magnetic field profiles across 6 terrestrial bow shock and one interplanetary shock are examined. The interplanetary shock illustrates the behavior of a low Mach number shock. It had an upstream whistler wave precursor with an apparent wavelength of 180 km. The shock thickness was about 90 km for the thickness of the final field jump or 270

C. T. Russell; E. W. Greenstadt

1979-01-01

406

3D Dynamic Rupture Simulation Across a Complex Fault System: the Mw7.0, 2010, Haiti Earthquake  

NASA Astrophysics Data System (ADS)

Earthquakes ruptures sometimes take place on a secondary fault and surprisingly do not activate an adjacent major one. The 1989 Loma Prieta earthquake is a classic case where rupture occurred on a blind thrust while the adjacent San Andreas Fault was not triggered during the process. Similar to Loma Prieta, the Mw7.0, January 12 2010, Haiti earthquake also ruptured a secondary blind thrust, the Léogâne fault, adjacent to the main plate boundary, the Enriquillo Plantain Garden Fault, which did not rupture during this event. Aftershock relocalizations delineate the Léogâne rupture with two north dipping segments with slightly different dip, where the easternmost segment had mostly dip-slip motion and the westernmost one had mostly strike-slip motion. In addition, an offshore south dipping structure inferred from the aftershocks to the west of the rupture zone coincides with the offshore Trois Baies reverse fault, a region of increase in Coulomb stress increase. In this study, we investigate the rupture dynamics of the Haiti earthquake in a complex fault system of multiple segments identified by the aftershock relocations. We suppose a background stress regime that is consistent with the type of motion of each fault and with the regional tectonic regime. We initiate a nucleation on the east segment of the Léogâne fault by defining a circular region with a 2 km radius where shear stress is slightly greater than the yield stress. By varying friction on faults and background stress, we find a range of plausible scenarios. In the absence of near-field seismic records of the event, we score the different models against the static deformation field derived from GPS and InSAR at the surface. All the plausible simulations show that the rupture propagates from the eastern to the western segment along the Léogâne fault, but not on the Enriquillo fault nor on the Trois Baies fault. The best-fit simulation shows a significant increase of shear stresses on the Trois Baies fault, which might explain observed triggered aftershocks on this fault and small increase of shear stresses on the Enriquillo fault. We also find that a shift to north of about 3 km of the western segment of the Léogâne fault from recent studies provides a better fit to the coseismic InSAR and GPS displacements.

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

2013-12-01

407

Life-threatening rupture of an external iliac artery pseudoaneurysm caused by necrotizing fasciitis following laparoscopic radical cystectomy: a case report  

PubMed Central

Background Pseudoaneurysms are caused by trauma, tumors, infections, vasculitis, atherosclerosis and iatrogenic complications. In this paper, we report about a patient with rupture of an external iliac artery pseudoaneurysm, which lead to hemorrhagic shock, after undergoing laparoscopic radical cystectomy and extended pelvic lymphadenectomy. Case presentation The patient was a 68-year-old Japanese male diagnosed with invasive bladder cancer. Laparoscopic radical cystectomy and extended pelvic lymphadenectomy were performed. On postoperative day 12, he developed a high fever and an acute inflammatory response with redness and swelling in the right inguinal region. He was diagnosed with necrotizing fasciitis and underwent debridement. On postoperative day 42, a sudden hemorrhage developed from the open wound in the right inguinal region. He was diagnosed with external iliac artery pseudoaneurysm rupture by computed tomography. Conclusion These complications occur extremely rarely after cystectomy with pelvic lymphadenectomy. There are no reports to date on these complications following laparoscopic cystectomy with pelvic lymphadenectomy. PMID:24885366

2014-01-01

408

In-reactor creep rupture of 20% cold-worked AISI 316 stainless steel  

Microsoft Academic Search

Results of an experiment designed to measure in-reactor stress-to-rupture properties of 20% cold-worked AISI 316 stainless steel are reported. The in-reactor rupture data are compared with postirradiation and unirradiated test results. In-reactor rupture lives were found to exceed rupture predictions of postirradiation tests. This longer in-reactor rupture life is attributed to dynamic point defect generation which is absent during postirradiation

A. J. Lovell; B. A. Chin; E. R. Gilbert

1981-01-01

409

Failure analysis of the main rotor grip of a civil helicopter  

Microsoft Academic Search

This paper analyses the causes of a rupture which occurred with the main rotor grip device of a civil helicopter, which failed when the aircraft was attempting to land. From the visual examination of the fractured surface, it was possible to observe typical beach marks, thus indicating the occurrence of fatigue failure. Further examination, by using scanning electron microscopy (SEM)

N. J. Lourenço; C. F. A. Von Dollinger; M. L. A. Graça; P. P. de Campos

2005-01-01

410

Shock-Protection Improvement Using Integrated Novel Shock-Protection Technologies  

Microsoft Academic Search

This paper presents the design and results of shock experiments conducted to demonstrate the advantages of two novel shock-protection technologies: 1) nonlinear spring shock stops and 2) soft coating shock stops. Both technologies basically employ the conventional idea of hard shock stops to decouple de- vice design from shock-protection design but are specialized to re- duce impact force, which is

Sang Won Yoon; Sangwoo Lee; Noel C. Perkins; Khalil Najafi

2011-01-01

411

Interaction between reflected shock wave and unsteady jet in a shock tube experiment  

Microsoft Academic Search

Few shock tube experiments have been conducted for the integration of unsteady jets with propagating normal shock waves. Attention is presently given to the details of the shock structure behind the shock front during the interaction period. It is found that, when the unstable reflected shock wave of the hemispherical front recovers to the stable normal plane shock front, it

Yoshimi Ishii; Fumio Higashino; Akira Sakurai

1988-01-01

412

Investigation of the unsteady Edney type IV and VII shock-shock interaction  

E-print Network

of an incident shock wave which impinges on the bow shock in front of a blunt body. A supersonic jet forms1 Investigation of the unsteady Edney type IV and VII shock-shock interaction Christian Windisch1, 52056 Aachen, Germany Edney type IV and type VII shock-shock interactions are complex hypersonic flow

413

Shock Absorbing System  

NASA Technical Reports Server (NTRS)

A lightweight, inexpensive shock-absorbing system, developed by Langley Research Center 20 years ago, is now in service as safety device for an automated railway at Duke University Medical Center. The transportation system travels at about 25 miles per hour, carrying patients, visitors, staff and cargo. At the end of each guideway of the system are "frangible," (breakable) tube "buffers." If a slowing car fails to make a complete stop at the terminal, it would bump and shatter the tubes, absorbing energy that might otherwise jolt the passengers or damage the vehicle.

1982-01-01

414

Shock aurora: Ground-based imager observations X.-Y. Zhou,1  

E-print Network

Shock aurora: Ground-based imager observations X.-Y. Zhou,1 K. Fukui,2 H. C. Carlson,3 J. I. Moen,4; published 23 December 2009. [1] This paper studies dayside shock aurora forms and their variations observed. The intensified green emissions were mainly diffuse aurora on closed field lines. They were latitudinally below

California at Berkeley, University of

415

Current state and trends of ensuring traceability for vibration and shock measurements  

Microsoft Academic Search

Recent and current activities at the level of national metrology institutes (NMIs) towards ensuring traceability of vibration and shock measurements to the International System of Units are mainly twofold: (i) initiating and contributing to new international standardization projects, within the International Organization for Standardization, ISO TC 108, to specify upgraded or new standard methods for the vibration and shock calibration

H-J von Martens

1999-01-01

416

Earthquake recurrence and fault behavior on the Homestead Valley fault -- Central segment of the 1992 Landers surface rupture sequence  

SciTech Connect

The 1992 M 7.5 Landers earthquake produced complex surface rupture on sections of the previously mapped Johnson Valley, Homestead Valley, and Emerson faults. The earthquake has raised questions about new faulting, characteristic earthquakes, and fault segmentation. To address these issues the authors initiated a study of both ruptured and unruptured fault segments, and report initial observations on the Homestead Valley fault (HVF). The authors site is located at the distal end of a large alluvial fan where 1992 right slip was 3 m, vertical slip was 40 cm, and the rupture followed pre-existing NE-facing scarps. Two trenches provide clear evidence of the two most recent pre-1992 surface faulting events. The trenches exposed alluvial fan and scarp derived colluvial deposits that are displaced and locally warped by both vertical strike-slip and low angle reverse-oblique( )-slip faults. At the main fault trace two pre-1992 colluvial wedges overlie a distinctive Bt soil horizon of late( ) Pleistocene age. Colluvium from the penultimate event has weak soil development, indicating a Holocene age for this faulting; apparent vertical displacement from this event is 35 cm, essentially the same as 1992. Preliminary observations indicate that recurrence of large magnitude earthquakes on faults of the Eastern California Shear Zone is one to two orders of magnitude longer than on major faults of the San Andreas system. The length of the HVF is short for this amount of offset, which suggests prior events may have also involved the rupture of multiple fault segments.

Cinti, F.R. (ING, Rome (Italy)); Fumal, T.E.; Garvin, C.D.; Hamilton, J.C.; Powers, T.J.; Schwartz, D.P. (Geological Survey, Menlo Park, CA (United States))

1993-04-01

417

Loading of the san andreas fault by flood-induced rupture of faults beneath the salton Sea  

USGS Publications Warehouse

The southern San Andreas fault has not experienced a large earthquake for approximately 300 years, yet the previous five earthquakes occurred at ???180-year intervals. Large strike-slip faults are often segmented by lateral stepover zones. A Movement on smaller faults within a stepover zone could perturb the main fault segments and potentially trigger a large earthquake. The southern San Andreas fault terminates in an extensional stepover zone beneath the Salton Sea-a lake that has experienced periodic flooding and desiccation since the late Holocene. Here we reconstruct the magnitude and timing of fault activity beneath the Salton Sea over several earthquake cycles. We observe coincident timing between flooding events, stepover fault displacement and ruptures on the San Andreas fault. Using Coulomb stress models, we show that the combined effect of lake loading, stepover fault movement and increased pore pressure could increase stress on the southern San Andreas fault to levels sufficient to induce failure. We conclude that rupture of the stepover faults, caused by periodic flooding of the palaeo-Salton Sea and by tectonic forcing, had the potential to trigger earthquake rupture on the southern San Andreas fault. Extensional stepover zones are highly susceptible to rapid stress loading and thus the Salton Sea may be a nucleation point for large ruptures on the southern San Andreas fault. ?? 2011 Macmillan Publishers Limited. All rights reserved.

Brothers, D.; Kilb, D.; Luttrell, K.; Driscoll, N.; Kent, G.

2011-01-01

418

Structural control on the Tohoku earthquake rupture process investigated by 3D FEM, tsunami and geodetic data.  

PubMed

The 2011 Tohoku earthquake (Mw = 9.1) highlighted previously unobserved features for megathrust events, such as the large slip in a relatively limited area and the shallow rupture propagation. We use a Finite Element Model (FEM), taking into account the 3D geometrical and structural complexities up to the trench zone, and perform a joint inversion of tsunami and geodetic data to retrieve the earthquake slip distribution. We obtain a close spatial correlation between the main deep slip patch and the local seismic velocity anomalies, and large shallow slip extending also to the North coherently with a seismically observed low-frequency radiation. These observations suggest that the friction controlled the rupture, initially confining the deeper rupture and then driving its propagation up to the trench, where it spreads laterally. These findings are relevant to earthquake and tsunami hazard assessment because they may help to detect regions likely prone to rupture along the megathrust, and to constrain the probability of high slip near the trench. Our estimate of ~40 m slip value around the JFAST (Japan Trench Fast Drilling Project) drilling zone contributes to constrain the dynamic shear stress and friction coefficient of the fault obtained by temperature measurements to ~0.68 MPa and ~0.10, respectively. PMID:25005351

Romano, F; Trasatti, E; Lorito, S; Piromallo, C; Piatanesi, A; Ito, Y; Zhao, D; Hirata, K; Lanucara, P; Cocco, M

2014-01-01

419

Structural control on the Tohoku earthquake rupture process investigated by 3D FEM, tsunami and geodetic data  

NASA Astrophysics Data System (ADS)

The 2011 Tohoku earthquake (Mw = 9.1) highlighted previously unobserved features for megathrust events, such as the large slip in a relatively limited area and the shallow rupture propagation. We use a Finite Element Model (FEM), taking into account the 3D geometrical and structural complexities up to the trench zone, and perform a joint inversion of tsunami and geodetic data to retrieve the earthquake slip distribution. We obtain a close spatial correlation between the main deep slip patch and the local seismic velocity anomalies, and large shallow slip extending also to the North coherently with a seismically observed low-frequency radiation. These observations suggest that the friction controlled the rupture, initially confining the deeper rupture and then driving its propagation up to the trench, where it spreads laterally. These findings are relevant to earthquake and tsunami hazard assessment because they may help to detect regions likely prone to rupture along the megathrust, and to constrain the probability of high slip near the trench. Our estimate of ~40 m slip value around the JFAST (Japan Trench Fast Drilling Project) drilling zone contributes to constrain the dynamic shear stress and friction coefficient of the fault obtained by temperature measurements to ~0.68 MPa and ~0.10, respectively.

Romano, F.; Trasatti, E.; Lorito, S.; Piromallo, C.; Piatanesi, A.; Ito, Y.; Zhao, D.; Hirata, K.; Lanucara, P.; Cocco, M.

2014-07-01

420

Creep-rupture behavior of candidate Stirling engine iron supperalloys in high-pressure hydrogen. Volume 2: Hydrogen creep-rupture behavior  

NASA Technical Reports Server (NTRS)

The creep rupture behavior of nine iron base and one cobalt base candidate Stirling engine alloys is evaluated. Rupture life, minimum creep rate, and time to 1% strain data are analyzed. The 3500 h rupture life stress and stress to obtain 1% strain in 3500 h are also estimated.

Bhattacharyya, S.; Peterman, W.; Hales, C.

1984-01-01

421

Hemodynamic-Morphologic Discriminants for Intracranial Aneurysm Rupture  

PubMed Central

Background and Purpose To identify significant morphologic and hemodynamic parameters that discriminate intracranial aneurysm (IA) rupture status using 3D angiography and computational fluid dynamics (CFD). Methods 119 IAs (38 ruptured, 81 unruptured) were analyzed from 3D angiographic images and CFD. Six morphologic and seven hemodynamic parameters were evaluated for significance with respect to rupture. Receiver-operating characteristic (ROC) analysis identified area under the curve (AUC) and optimal thresholds separating ruptured from unruptured aneurysms for each parameter. Significant parameters were examined by multivariate logistic regression analysis in 3 predictive models—morphology only, hemodynamics only, and combined—to identify independent discriminants, and the AUC-ROC of the predicted probability of rupture status was compared among these models. Results Morphologic parameters (Size Ratio [SR], Undulation Index, Ellipticity Index, and Nonsphericity Index) and hemodynamic parameters (Average Wall Shear Stress [WSS], Maximum intra-aneurysmal WSS, Low WSS Area, Average Oscillatory Shear Index [OSI], Number of Vortices, and Relative Resident Time) achieved statistical significance (p<0.01). Multivariate logistic regression analysis demonstrated SR to be the only independent