New physics of supersonic ruptures

Until recently,it is believed that the rupture speed above the pressure wave is impossible since spontaneously propagating ruptures are driven by the energy released due to the rupture motion,which is transferred through the medium to the rupture tip region at the maximum speed equal to the pressure wave speed.However,the apparent violation of classic theories has been revealed by new experimental results demonstrating supersonic shear ruptures.This paper presents a detailed analysis of the recently discovered shear rupture mechanism(fan hinged),which suggests a new physics of energy supply to the tip of supersonic ruptures.The key element of this mechanism is the fan‐shaped structure of the head of extreme ruptures,which is formed as a result of an intense tensile cracking process with the creation of intercrack slabs that act as hinges between the shearing rupture faces.The fan structure is featured with the following extraordinary properties:extremely low friction approaching zero;amplification of shear stresses above the material strength at low applied shear stresses;creation of a self‐disbalancing stress state causing a spontaneous rupture growth;abnormally high energy release;generation of driving energy directly at the rupture tip which excludes the need to transfer energy through the medium.The fan mechanism operates in intact rocks at stress conditions corresponding to seismogenic depths and in pre‐existing extremely smooth interfaces due to identical tensile cracking processes at these conditions.This is Paper 1(of two companion papers)which discusses the fan theory and extreme ruptures in experiments on extremely smooth interfaces.Paper 2 entitled“Fan‐hinged shear instead of frictional stick‐slip as the main and most dangerous mechanism of natural,induced and volcanic earthquakes in the earth's crust”considers extreme ruptures in intact rocks.Further study of this subject is a major challenge for deep underground science,earthquake and fracture mechanics,physics,and tribology.

Multiple flexor tendon ruptures due to osteochondroma of the hamate:A case report

BACKGROUND Closed rupture of the little and ring finger flexor tendons caused by the hamate is mostly associated with a fracture or nonunion of the hamate hook.Only one case of a closed rupture of the finger flexor tendon caused by osteochondroma in the hamate has been reported.Here,we present a case study to highlight the possibility of hamate osteochondroma as a rare cause of finger closed flexor tendon rupture based on our clinical experience and literature review.CASE SUMMARY A 48-year-old man who had been a rice-field farmer for 7–8 h a day for the past 30 years visited our clinic due to the loss of right little finger and ring finger flexion involving both the proximal and distal interphalangeal joints.The patient was diagnosed with a complete rupture of the ring and little finger flexors because of the hamate and was pathologically diagnosed with an osteochondroma.Exploratory surgery was performed,and a complete rupture of the ring and little finger flexors due to an osteophyte-like lesion of the hamate was observed,which was pathologically diagnosed as an osteochondroma.CONCLUSION One should consider that osteochondroma in the hamate may be the cause of closed tendon ruptures.

Comparison of surgical intervention with functional treatment for acute ruptures of lateral ankle ligmant:a meta-analysis

Objective:To compare the effect of surgical intervention on functional treatment.Methods: By searching the MEDLINE(1966 to October 2011),EMBASE(1980 to October 2011),the Chinese Biomedical Database Databases(1980 to October 2011),a total of 9 related RCT studies comparing surgical intervention with functional treatment were included in our study.RevMan software was taken to analyze the data.Results:These 9 studies Involved a total of 1 268 mostly young adults,including 580 patients with surgical treatment and 688 patients with functional treatment.The results showed the stability of ankle activity in surgical treatment group was better than that in functional treatment group,with the OR and 95%CI of 0.72(0.52-0.99).No significant difference was found in the recurrence of the surgical and functional group.However, the movement disorder in the surgical treatment suggested increased risk than that in functional group,with the OR and 95%CI of 2 39(0.98-5.85).Surgical group found more complication than the function group,such as deep vein thrombosis,deep venous thrombosis,tenderness of scar and sensory loss.Conclusions:In conclusion,our finding showed that surgical treatment could gain better efficacy than functional treatment,but may bring more complication.Therefore,further large sample size RCT is warranted.

Parameters of Coseismic Reverse- and Oblique-Slip Surface Ruptures of the 2008 Wenchuan Earthquake,Eastern Tibetan Plateau

On May 12th, 2008, the Mw7.9 Wenchuan earthquake ruptured the Beichuan, Pengguan and Xiaoyudong faults simultaneously along the middle segment of the Longmenshan thrust belt at the eastern margin of the Tibetan plateau. Field investigations constrain the surface rupture pattern, length and offsets related to the Wenchuan earthquake. The Beichuan fault has a NE-trending rightlateral reverse rupture with a total length of 240 km. Reassessment yields a maximum vertical offset of 6.5±0.5 m and a maximum right-lateral offset of 4.9±0.5 m for its northern segment, which are the largest offsets found; the maximum vertical offset is 6.2±0.5 m for its southern segment. The Pengguan fault has a NE-trending pure reverse rupture about 72 km long with a maximum vertical offset of about 3.5 m. The Xiaoyudong fault has a NW-striking left-lateral reverse rupture about 7 km long between the Beichuan and Pengguan faults, with a maximum vertical offset of 3.4 m and left-lateral offset of 3.5 m. This pattern of multiple co-seismic surface ruptures is among the most complicated of recent great earthquakes and presents a much larger danger than if they ruptured individually. The rupture length is the longest for reverse faulting events ever reported.

Rapid Identification and Emergency Investigation of Surface Ruptures and Geohazards Induced by the M_s 7.1 Yushu Earthquake

The rapid identification based on InSAR technology was proved to be effective in our emergency investigation of surface ruptures and geohazards induced by the Yushu earthquake.The earthquake-generating fault of the Yushu earthquake is the Yushu section of the Garze-Yushu faults zone.It strikes NWW-NW,23 km long near the Yushu County seat,dominated by left-lateral strike slip,and appearing as a surface rupture zone.The macroscopic epicenter is positioned at Guo-yang-yan -song-duo of Gyegu Town（33°03＇11＂N,96°51＇26＂E）,where the co-seismic horizontal offset measured is 1.75 m.Geohazards induced by the Yushu earthquake are mainly rockfalls,landslides,debris flows, and unstable slopes.They are controlled by the earthquake-generating fault and are mostly distributed along it.There are several geohazard chains having been established,such as earthquake,canal damage,soil liquefying,landslide-debris flow,earthquake,soil liquefying,roadbed deformation,etc.In order to prevent seismic hazards,generally,where there is a visible surface rupture induced by the Yushu earthquake,reconstruction should be at least beyond 20 m,on each side,from it.Sufficient attention should also be given to potential geohazards or geohazard chains induced by the earthquake.

Analysis of Remote Sensing Images of Ground Ruptures Resulting from the Kunlun Mountain Pass Earthquake in 2001

On November 14, 2001, an earthquake measuring a magnitude of 8.1 occurred to the west of the Kunlun Mountain Pass which is near the border between Xinjiang and Qinghai of China. Since its epicenter is located in an area at an elevation of 4900 m where the environment is extremely adverse, field investigation to this event seems very difficult. We have performed interpretation and analysis of the satellite images of ETM, SPOT, Ikonos, and ERS-1/2SAR to reveal the spatial distribution and deformation features of surface ruptures caused by this large earthquake. Our results show that the rupture zone on the ground is 426 km long, and strikes N90-110°E with evident left-lateral thrusting. In spatial extension, it has two distinct sections. One extends from the Bukadaban peak to the Kunlun Mountain Pass, with a total length of 350 km, and trending N95-110°E. Its fracture plane is almost vertical, with clear linear rupture traces and a single structure, and the maximum left-lateral offset is 7.8 m. This section is the main rupture zone caused by the earthquake, which is a re-fracturing along an old fault. The other is the section from Kushuihuan to the Taiyang Lake. It is 26 km long, trending N90-105°E, with the maximum strike-slip displacement being 3 m, and is a newly-generated seismic rupture. In a 50 km-long section between the Taiyang Lake and the Bukadaban peak, no rupture is found on the ground. The eastern and western rupture zones may have resulted from two earthquakes. The macroscopic epicenter is situated at 65 km east of the Hoh Sai Lake. The largest coseismic horizontal offset in the macroscopic epicenter ranges from 7 m to 8 m. Based on the dislocation partition of the whole rupture zone, it is suggested that this rupture zone has experienced a process of many times of intensification and fluctuation, exhibiting a remarkable feature of segmentation.

Deformation of the Most Recent Co-seismic Surface Ruptures Along the Garzê–Yushu Fault Zone(Dangjiang Segment)and Tectonic Implications For the Tibetan Plateau

The Garzê–Yushu strike-slip fault in central Tibet is the locus of strong earthquakes（M 〉 7）. The deformation and geometry of the co-seismic surface ruptures are reflected in the surface morphology of the fault and depend on the structure of the upper crust as well as the pre-existing tectonics. Therefore, the most recent co-seismic surface ruptures along the Garzê–Yushu fault zone（Dangjiang segment） reveal the surface deformation of the central Tibetan Plateau. Remote sensing images and field investigations suggest a 85 km long surface rupture zone（striking NW-NWW）, less than 50 m wide, defined by discontinuous fault scarps, right-stepping en echelon tensional cracks and left-stepping mole tracks that point to a left-lateral strike-slip fault. The gullies that cross fault scarps record systematic left-lateral offsets of 1.8 m to 5.0 m owing to the most recent earthquake, with moment magnitude of about M 7.5, in the Dangjiang segment. Geological and geomorphological features suggest that the spatial distribution of the 1738 co-seismic surface rupture zone was controlled by the pre-existing active Garzê–Yushu fault zone（Dangjiang segment）. We confirm that the Garzê–Yushu fault zone, a boundary between the Bayan Har Block to the north and the Qiangtang Block to the south, accommodates the eastward extrusion of the Tibetan Plateau and generates strong earthquakes that release the strain energy owing to the relative motion between the Bayan Har and Qiangtang Blocks.

Segmentations of active normal dip-slip faults around Ordos block according to their surface ruptures in historical strong earthquakes

From the results of researches of active faults in resent years, a correlation analysis between segments of the faults according to surface ruptures in nine historical strong earthquakes occurring in downfaulted system and active structures around Ordos block is conducted in paper. The result shows that there is a good correlation between them, except few individual data that have more uncertain parameters. It shows that intensity and segments of surface ruptures in these strong earthquakes are intrinsically related with the active structures. These strong earthquakes produced stable and unstable rupture boundaries of characteristic-earthquake type and successive occurrence of strong earthquakes on the different boundary faults in the same tectonic unit.

High-resolution structure-from-motion models covering 160 km-long surface ruptures of the 2021 M_(W)7.4 Madoi earthquake in northern Qinghai-Tibetan Plateau

The May 222021 M_(W)7.4 Madoi,Qinghai,China earthquake presented a rare opportunity to apply the modern unmanned aerial vehicle(UAV)photography method in extreme altitude and weather conditions to image surface ruptures and near-field effects of earthquake-related surface deformations in the remote Tibet.High-resolution aerial photographs were acquired in the days immediately following the mainshock.The complex surface rupture patterns associated with this event were covered comprehensively at 3-6 cm resolution.This effort represents the first time that an earthquake rupture in the interior of the Qinghai-Tibetan Plateau has been fully and systematically captured by such high-resolution imagery,with an unprecedented level of detail,over its entire length.The dataset has proven valuable in documenting subtle and transient rupture features,such as the significant mole-tracks and opening fissures,which were ubiquitous coseismically but degraded during the subsequent summer storm season.Such high-quality imagery also helps to document with high fidelity the fractures of the surface rupture zone(supplements of this paper),the pattern related to how the faults ruptured to the ground surface,and the distribution of off-fault damage.In combination with other ground-based mapping efforts,the data will be analyzed in the following months to better understand the mechanics of earthquake rupture related to the fault zone rheology,rupture dynamics,and frictional properties along with the fault interface.

Seismic source ruptures of several strong earth-quakes of 1989 in Sichuan region of China

Several strong earthquakes occurred in the regions of Batang and Xiaojin of Sichuan Province in 1989. This paper uses broadband waveform data from GDSN, by the forward trial-and-error modeling for multiple subevent, in terms of analysis on quasi-source time function or qSTF of station, to study source rupture characteristics of these strong earthquakes and to discuss tectonic background of earthquake occurrence regions preliminarily.

Best approach for the repair of distal biceps tendon ruptures

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

Relationship between the Pre-existing Active Kunlun Fault and Co-seismic Surface Ruptures Produced by the 2001 Mw 7.8 Central Kunlun Earthquake, China

Field investigations allow to constrain the co-seismic surface rupture zone of ～400 km with a strike-slip up to 16.3 m associated with the 2001 Mw 7.8 Central Kunlun earthquake that occurred along the western segmentof the Kunlun fault, northern Tibet. The co-seismic rupture structures are almost duplicated on the pre-existing fault traces of the Kunlun fault. The deformational characteristics of the co-seismic surface ruptures reveal that the earthquake had a nearly pure strike-slip mechanism. The geologic and topographic evidence clearly shows that spatialdistributions of the co-seismic surface ruptures are restricted by the pre-existing geological structures of the Kunlun fault.

Relocating ruptures of two M6 earthquakes in Zhongba, South-central Tibet in 2004 and 2005 with seismological and geodetic methods

To better understand repeatability of strong earthquakes in previously ruptured zones during one seismogenic period, we studied the rupture zones of the doublet of M6 earthquakes in Zhongba region of southcentral Tibet, China, in 11 July 2004 and 7 April 2005, respectively. We focused on the overlapping degree of two strong quakes’ aftershock areas one week after the mainshocks by using the SQH station in China Seismic Network and a 68-stations temporary broadband seismic array, a part of the international HI-CLIMB project. About 115 local earthquakes were recorded in one week after the mainquakes, and we located these earthquakes by master event relative location （MERL） method. We also used this method to relocate 31 other M3.7 ＋ earthquakes from 1 July 2004 to 1 July 2005. Meanwhile, we studied two mainshocks’ coseismic ruptures with satellite interferometric synthetic aperture radar （InSAR）. Our results show that the ruptured zones of the two earthquakes do not overlapp substantially, either from early aftershock data or from InSAR inversions.

Hybrid Repair of Two Consecutive Acute Ventricular Septal Ruptures after Evolving Myocardial Infarction: Case Report

Background: Acute Ventricular septal rupture is one of dreadful complications of acute evolving myocardial infarction. Despite urgent management is lifesaving, it is still challenging and has a high risk of mortality particularly if recurrent or residual defects occurred. Evolving of skillfulness in transcatheter intervention of heart diseases paved the way for successful hybrid management of challenging cardiac cases specially for residual complicated cases post cardiac surgery. Case Presentation: We described here a successful hybrid two stage technique (surgical then transcatheter approach) to close two consecutive acute ventricular septal ruptures in 75 years old female presented with cardiogenic shock post evolving myocardial infarction. Conclusion: Hybrid repair by surgical and transcatheter interventions may be a good therapeutic modality for acute septal ruptures specially for residual or new defects after initial closure.

Jejuno-Ileal Ruptures after Blunt Abdominal Trauma at the Teaching Hospital of Bouake

Objective: The aim of this study is to determine the causes, pattern, management, and outcome of jejunal-ileal rupture following blunt abdominal trauma at the teaching Hospital of Bouake. Methods: The study included 27 patients who underwent laparotomy for jejunoileal injuries from blunt abdominal trauma at the Teaching Hospital of Bouake over a period of 14 years from January 2007 to December 2020. A retrospective study was conducted and the patients were analyzed with respect to patient demographics data, cause, injury mechanisms, presentation, anatomical distribution, diagnostic methods, associated injuries, treatment and outcomes. Results: During the 14 year period from 2007 to 2020, 27 patients with blunt small bowel injuries were treated at our Teaching Hospital. That is 2.9% of all blunt abdominal trauma. Male to female ratio was 4.4:1 and the average age was 26.3 years (range: 15 and 50 years). The majority (66.7% 18 cases) were Victims of road traffic accident. Median delay between injury and arrival at hospital for these patients was 10.1 hours (range: 1 - 72 h). A single intestinal injury was present in 22 patients, while 5 patients suffered from 2 injuries. There were 32 perforations of the small intestine in 27 patients with two perforations being transection. All perforations were located on the antimesenteric border of the intestine. Out of the 32 jejuno-ileal ruptures 18 were located on the jejunum while 14 were located on the ileum. Associated intra-abdominal injuries were present in 6 patients and nineteen associated extra-abdominal injuries were present in 10 (70.4%) patients. A one-stage therapeutic strategy was performed in 20 cases (74.1%) and a two-stage strategy was performed in seven cases (25.9%). Intestinal continuity was restored 93.8 days later (range 60 and 140 days). The average length of hospital stay of the operated patients was 11.4 days. The operative morbidity was 25.9%. Conclusion: Jejuno-ileal ruptures are rare and characterized by a delay in management. An early diagnosis could improve the vital prognosis of the patients.

Iatrogenic Tracheal Ruptures: Review of the Literature and Personal Experience on 11 Cases

Objective: Iatrogenic tracheal rupture is a rare, but life-threatening complication of orotracheal intubation. In this retrospective study, etiology, and diagnostic and therapeutic approaches for iatrogenic tracheal ruptures were reviewed. Method: Eleven patients (6 males and 5 females) were diagnosed and treated for iatrogenic tracheal rupture in our clinic. The laceration occurred after orotracheal intubation in 7 cases, and during percutaneous tracheostomy and emergency tracheostomy in the other four cases, respectively. Diagnosis was made during thoracic surgery in 5 cases. The remaining cases were diagnosed in the post-operative period;the most common symptoms were mediastinal and subcutenous emphysema and pneumothorax. Results: The diagnosis was confirmed by bronchoscopy in all cases. The lacerations were longitudinal, 1-7 cm in length and were located in the distal membranous trachea. While ruptures detected intraoperatively were repaired during the surgery, the others were treated conservatively. No mortality was observed among cases treated surgically. However, three of the cases treated conservatively died (50%), and the cause of death was the underlying disease requiring intubation. Conclusion: We are in the opinion that primary disease is a determinant of patient outcome. Except cases identified during surgery, emergency surgical interventions should be preferred in patients, in whom ventilation cannot be achieved. On the other hand, bronchoscopic fibrin glue instillation should additively be applied to conservative treatment of tracheal lacerations.

腹腔镜子宫肌瘤剔除术与妊娠期子宫破裂的研究进展

子宫肌瘤是育龄期女性常见多发疾病,腹腔镜子宫肌瘤剔除术是目前临床最常用的治疗方法。子宫肌瘤剔除术后妊娠期子宫破裂(uterine rupture during pregnancy,URDP)是最严重的远期并发症,可能会造成灾难性的后果,必须引起临床医生的足够重视。本文对腹腔镜子宫肌瘤剔除术后URDP的预后因素进行文献总结,为妇科医生手术提供临床依据,提高手术技巧,将URDP的风险降到最低。

Cascading multi-segment rupture process of the 2023 Turkish earthquake doublet on a complex fault system revealed by teleseismic P wave back projection method

In this study,the vertical components of broadband teleseismic P wave data recorded by China Earthquake Network are used to image the rupture processes of the February 6th,2023 Turkish earthquake doublet via back projection analysis.Data in two frequency bands(0.5-2 Hz and 1-3 Hz)are used in the imaging processes.The results show that the rupture of the first event extends about 200 km to the northeast and about 150 km to the southwest,lasting~90 s in total.The southwestern rupture is triggered by the northeastern rupture,demonstrating a sequential bidirectional unilateral rupture pattern.The rupture of the second event extends approximately 80 km in both northeast and west directions,lasting~35 s in total and demonstrates a typical bilateral rupture feature.The cascading ruptures on both sides also reflect the occurrence of selective rupture behaviors on bifurcated faults.In addition,we observe super-shear ruptures on certain fault sections with relatively straight fault structures and sparse aftershocks.

Rapid report of the December 18,2023 M_(S)6.2 Jishishan earthquake,Gansu,China

On December 18,2023,the Jishishan area in Gansu Province was jolted by a M_(S) 6.2 earthquake,which is the most powerful seismic event that occurred throughout the year in China.The earthquake occurred along the NWtrending Lajishan fault(LJSF),a large tectonic transformation zone.After this event,China Earthquake Networks Center(CENC)has timely published several reports about seismic sources for emergency responses.The earthquake early warning system issued the first alert 4.9 s after the earthquake occurrence,providing prompt notification that effectively mitigated panics,injuries,and deaths of residents.The near real-time focal mechanism solution indicates that this earthquake is associated with a thrust fault.The distribution of aftershocks,the rupture process,and the recorded amplitudes from seismic monitoring and GNSS stations,all suggest that the mainshock rupture predominately propagates to the northwest direction.The duration of the rupture process is~12 s,and the largest slip is located at approximately 6.3 km to the NNW from the epicenter,with a peak slip of 0.12 m at~8 km depth.Seismic station N0028 recorded the highest instrumental intensity,which is 9.4 on the Mercalli scale.The estimated intensity map shows a seismic intensity reaching up to IX near the rupture area,consistent with field survey results.The aftershocks(up to December 22,2023)are mostly distributed in the northwest direction within~20 km of the epicenter.This earthquake caused serious casualties and house collapses,which requires further investigations into the impact of this earthquake.

Hepatic rupture secondary to HELLP syndrome: outcomes in three cases

Hypertensive disorders of pregnancy,including chronic hypertension,gestational hypertension,and preeclampsia,are the most common complications in pregnant women,affecting approximately 15%of pregnancies.[1,2]Hemolysis,elevated liver enzymes,and low platelet count(HELLP syndrome)can occur in 0.2%-0.6%of all pregnancies,and 10%-15%of patients are diagnosed with preeclampsia.[3,4]Among its severe complications,liver hematoma is remarkable and may lead to liver rupture.Prompt identification of HELLP syndrome is crucial for proper therapeutic management and to avoid fatal outcomes[4,5]since when a hepatic hematoma occurs,the risk of rupture increases to 12%.[3,5]