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The Dead Sea Transform (DST) is a major left-lateral strike-slip fault that accommodates the relative motion between the African and Arabian plates, connecting a region of extension in the Red Sea to the Taurus collision zone in Turkey over a length of about 1100 km. The Dead Sea Basin (DSB) is one of the largest basins along the DST. The DSB is a morphotectonic depression along the DST, divided into a northern and a southern sub-basin, separated by the Lisan salt diapir. We report on a receiver function study of the crust within the multidisciplinary geophysical project, DEad Sea Integrated REsearch (DESIRE), to study the crustal structure of the DSB. A temporary seismic network was operated on both sides of the DSB between 2006 October and 2008 April. The aperture of the network is approximately 60 km in the E-W direction crossing the DSB on the Lisan peninsula and about 100 km in the N-S direction. Analysis of receiver functions from the DESIRE temporary network indicates that Moho depths vary between 30 and 38 km beneath the area. These Moho depth estimates are consistent with results of near-vertical incidence and wide-angle controlled-source techniques. Receiver functions reveal an additional discontinuity in the lower crust, but only in the DSB and west of it. This leads to the conclusion that the internal crustal structure east and west of the DSB is different at the present-day. However, if the 107 km left-lateral movement along the DST is taken into account, then the region beneath the DESIRE array where no lower crustal discontinuity is observed would have lain about 18 Ma ago immediately adjacent to the region under the previous DESERT array west of the DST where no lower crustal discontinuity is recognized. [ABSTRACT FROM AUTHOR]

As part of the DEad Sea Integrated REsearch project (DESIRE) a 235 km long seismic wide-angle reflection/refraction (WRR) profile was completed in spring 2006 across the Dead Sea Transform (DST) in the region of the southern Dead Sea basin (DSB). The DST with a total of about 107 km multi-stage left-lateral shear since about 18 Ma ago, accommodates the movement between the Arabian and African plates. It connects the spreading centre in the Red Sea with the Taurus collision zone in Turkey over a length of about 1 100 km. With a sedimentary infill of about 10 km in places, the southern DSB is the largest pull-apart basin along the DST and one of the largest pull-apart basins on Earth. The WRR measurements comprised 11 shots recorded by 200 three-component and 400 one-component instruments spaced 300 m to 1.2 km apart along the whole length of the E–W trending profile. Models of the P-wave velocity structure derived from the WRR data show that the sedimentary infill associated with the formation of the southern DSB is about 8.5 km thick beneath the profile. With around an additional 2 km of older sediments, the depth to the seismic basement beneath the southern DSB is about 11 km below sea level beneath the profile. Seismic refraction data from an earlier experiment suggest that the seismic basement continues to deepen to a maximum depth of about 14 km, about 10 km south of the DESIRE profile. In contrast, the interfaces below about 20 km depth, including the top of the lower crust and the Moho, probably show less than 3 km variation in depth beneath the profile as it crosses the southern DSB. Thus the Dead Sea pull-apart basin may be essentially an upper crustal feature with upper crustal extension associated with the left-lateral motion along the DST. The boundary between the upper and lower crust at about 20 km depth might act as a decoupling zone. Below this boundary the two plates move past each other in what is essentially a shearing motion. Thermo-mechanical modelling of the DSB supports such a scenario. As the DESIRE seismic profile crosses the DST about 100 km north of where the DESERT seismic profile crosses the DST, it has been possible to construct a crustal cross-section of the region before the 107 km left-lateral shear on the DST occurred. [ABSTRACT FROM AUTHOR]

To address one of the central questions of plate tectonics—How do large transform systems work and what are their typical features?—seismic investigations across the Dead Sea Transform (DST), the boundary between the African and Arabian plates in the Middle East, were conducted for the first time. A major component of these investigations was a combined reflection/refraction survey across the territories of Palestine, Israel and Jordan. The main results of this study are: (1) The seismic basement is offset by 3–5 km under the DST, (2) The DST cuts through the entire crust, broadening in the lower crust, (3) Strong lower crustal reflectors are imaged only on one side of the DST, (4) The seismic velocity sections show a steady increase in the depth of the crust-mantle transition (Moho) from ∼26 km at the Mediterranean to ∼39 km under the Jordan highlands, with only a small but visible, asymmetric topography of the Moho under the DST. These observations can be linked to the left-lateral movement of 105 km of the two plates in the last 17 Myr, accompanied by strong deformation within a narrow zone cutting through the entire crust. Comparing the DST and the San Andreas Fault (SAF) system, a strong asymmetry in subhorizontal lower crustal reflectors and a deep reaching deformation zone both occur around the DST and the SAF. The fact that such lower crustal reflectors and deep deformation zones are observed in such different transform systems suggests that these structures are possibly fundamental features of large transform plate boundaries. [ABSTRACT FROM AUTHOR]

Background: Frailty is a distinctive health state associated with a loss of physiological reserve that results in higher rates of perioperative complications and impaired return to pre-morbid functional status. It is prevalent in the vascular population; however routine assessment is not common despite national guidance to the contrary. We aimed to evaluate the reliability of the Clinical Frailty Scale in assessing frailty in the surgical vascular population., Methods: In this prospective, observational, observer-blinded study, we compared assessment of frailty in patients scheduled for major vascular surgery attending the pre-operative assessment clinic using the Clinical Frailty Scale against the Edmonton Frailty Scale. The study investigator completed the Edmonton Frailty Scale assessment; this was compared to the Clinical Frailty Scale assessments performed by the pre-assessment consultant and pre-assessment nurse, who were blinded to the Edmonton Frailty Scale score. The inter-rater reliability of the Clinical Frailty Scale between the pre-assessment consultant and pre-assessment nurse was determined by comparing their frailty scores for each patient., Results: Ninety-seven patients were included in the analysis (median age 72 years, 84% male and 16% female). There was a moderate level of agreement between the Edmonton and Clinical Frailty Scale score for both consultants (87.6% agreement) and pre-assessment nurses (87.6% agreement). There was a substantial level of agreement between consultants and pre-assessment nurses for the Clinical Frailty Scale (89.7% agreement) CONCLUSIONS: The Clinical Frailty Scale is a useful tool to assess frailty in the vascular surgical population. It is more practical than the Edmonton Frailty Scale: quick to complete, requires minimal training and can be used when physical disability is present., Trial Registration: The study was approved by the Wales Health and Care Research Ethics Service (REC reference 17/WA/0160, IRAS 201173)., Trial Registration: NCT03403673. Registered 19 January 2018, https://clinicaltrials.gov/ct2/show/NCT03403673., (© 2022. The Author(s).)

The need for drainage after primary thyroid or parathyroid surgery was evaluated in a prospective study in which 100 consecutive patients were randomly allocated to drainage or no drainage. Seroma developed in the wound in seven of the 50 patients without drainage and in two of the 50 with drainage. There were no residual effects of the seromas, which resolved spontaneously. The incidence of wound complication was unrelated to the surgeon's opinion on the need for drainage. The study provided no statistical report for routine use of drains in primary thyroid or parathyroid surgery.

A case of ancient neurilemmoma (Schwannoma) is presented that, owing to a severe cell pleomorphism, was falsely interpreted as a malignant spindle-cell sarcoma by fine-needle aspiration cytology. Cytological features of the tumor are given together with its histopathology and electron microscopy findings. The usefulness of electron microscopy on material obtained by fine-needle aspiration biopsies in the diagnosis of soft-tissue tumors is discussed.

Two groups (n = 10 in each) of adult sheep were exposed to hemorrhagic shock resulting in mean arterial pressure (MAP) below 25 mmHg for 10 min. Following that, group A received crystalloids (8% of body wt) during one hr together with supraceliac intraaortic balloon tamponade during the first 30 min, while group B (controls) received crystalloids only. The central circulation was rapidly restored in group A, as indicated by increased MAP and increased systemic vascular resistance (SVR). After deflation of the balloon MAP dropped to the same value as in the control group, while cardiac index increased gradually with volume replacement and was significantly higher at the end of the resuscitation period (60 min) than in the control group (P less than 0.05). Despite a more rapid restoration of central hemodynamics in group A, lactic acidosis was more severe, acute renal failure and neurological complications more frequent, and mortality higher than in the control group. It was concluded that continuous supraceliac aortic occlusion for 30 min had deleterious effects on organs dependent on aortic blood flow distal to the aortic tamponade and may contribute to the development of multiple organ failure after resuscitation from hemorrhagic shock. Further studies are needed to evaluate the effects of intermittent intraaortic balloon tamponade in hemorrhagic shock.

While there is an abundant literature on popliteal artery injury secondary to penetrating trauma, few reports deal with popliteal artery injury caused by severe blunt trauma with or without fracture. Eight cases of popliteal artery injury are described. Seven of the patients had sustained blunt trauma, usually resulting also in damage to bone and soft tissues. The popliteal vein was involved in five of the injuries. The time lag between causal trauma and vascular repair averaged 25 hours. Delay was due mainly to failure to consult the vascular surgeon at an early stage. Leg amputation was necessary in two cases. Two patients died. The importance of early recognition of the vascular injury and appropriate surgical measures was illustrated in this small series of patients from a developing Middle Eastern country. Adequate fasciotomy, venous repair, use of intraoperative Doppler and repeated postoperative débridement are discussed in connection with management.

In a 29-year-old man with pyloric obstruction, plain abdominal radiography showed gas in the biliary tree. Gastroscopy revealed severe duodenal stenosis with a large posterior ulcer, and barium from a test meal passed into the common bile duct. Ten days after truncal vagotomy and gastrojejunostomy, signs of ascending cholangitis appeared. Following antibiotic treatment and cholecystectomy the patient recovered.

A case of spontaneous rupture of a solitary nonparasitic liver cyst is described. This rare condition was detected in a 36-year-old woman who underwent cholecystectomy and cyst excision 3 days after appendectomy. The preoperative diagnosis, including the role of HIDA scan (Hydroxyiminodiacetic acid) is discussed.