1,065 research outputs found
Light fluctuations, crown traits, and response delays for tree saplings in a Costa Rican lowland rain forest
Endovascular treatment of popliteal artery aneurysms: Results of a prospective cohort study
ObjectivePopliteal artery aneurysms can be treated endovascularly with less perioperative morbidity compared with open repair. To evaluate suitability of the endovascular technique and the clinical results of this treatment, we analyzed a prospective cohort of consecutive popliteal aneurysms referred to a tertiary university vascular center.MethodsAll popliteal artery aneurysms between June 1998 and June 2004 that measured >20 mm in diameter were analyzed for endovascular repair. Anatomic suitability was based largely on quality of the proximal and distal landing zone as determined by angiography. Endovascular treatment was performed by using a nitinol-supported expanded polytetrafluoroethylene lined stent graft introduced through the common femoral artery.ResultsWe analyzed 67 aneurysms in 57 patients. Ten aneurysms (15%) were excluded from endovascular repair, or from any repair at all, for various reasons. The remaining 57 (85%) were treated endovascularly, of which 5 were treated emergently for acute ischemia. During a mean 24-month follow-up, 12 stent grafts (21%) occluded. Primary and secondary patency rates were 80% and 90% at 1 year, and 77% and 87% at 2 years of follow-up. Postoperative treatment with clopidogrel proved to be the only significant predictor for success.ConclusionsEndovascular repair of a popliteal artery aneurysm is feasible. Changes in the material used and the addition of clopidogrel may improve patency rates
Geodesics and Geodesic Deviation in static Charged Black Holes
The radial motion along null geodesics in static charged black hole
space-times, in particular, the Reissner-Nordstr\"om and stringy charged black
holes are studied. We analyzed the properties of the effective potential. The
circular photon orbits in these space-times are investigated. We found that the
radius of circular photon orbits in both charged black holes are different and
differ from that given in Schwarzschild space-time. We studied the physical
effects of the gravitational field between two test particles in stringy
charged black hole and compared the results with that given in Schwarzschild
and Reissner-Nordstr\"om black holes.Comment: 12 pages, 5 figures, small changes, figures and references added,
conclusions changed. A improved, version accepted in Astrophysics and Space
Scienc
Is emergency endovascular aneurysm repair associated with higher secondary intervention risk at mid-term follow-up?
ObjectiveThe study assessed mid-term outcome of emergency endovascular repair for acute infrarenal abdominal aortic aneurysms, with special attention to secondary interventions.MethodsBetween May 1998 and August 2005, 56 patients underwent emergent endovascular repair for a ruptured abdominal aortic aneurysm (n = 34) or an acute nonruptured abdominal aortic aneurysm (n = 22). During the same period, 322 consecutive patients underwent elective endovascular aneurysm repair and were used as control group. Five types of stent grafts were used: Vanguard, Talent, Excluder, Zenith, and Quantum. Follow-up included abdominal radiograph, duplex ultrasound scanning, and computed tomographic angiography. Outcome measures included all-cause and aneurysm-related mortality, complications, and secondary interventions.ResultsMortality at 30 days was 18%, 5%, and 1% in the ruptured, acute nonruptured, and elective aneurysm groups, respectively. Overall mean follow-up was 38 ± 26 months. In the ruptured aneurysm group, survival was 67.8% ± 8.6% at 1 year and 62.1% ± 9.5% at 2 and 3 years. Seven secondary interventions (4 early and 3 late) were required in five patients (15%), with a cumulative risk of 9.2% ± 5.1% at 1 year and 16.2% ± 8.2% at 2 and 3 years. In the acute nonruptured aneurysm group, survival was 90.9% ± 6.1% at 1 year, 84.8% ± 8.2% at 2 years, and 76.4% ± 10.9% at 3 years. Four secondary interventions (1 early and 3 late) were required in four patients (18%), with a cumulative risk of 9.6% ± 6.5% at 1 and 2 years and 20.9% ± 12.0% at 3 years. In the elective aneurysm (control) group, survival was 95.2% ± 1.2% at 1 year, 89.9% ± 1.8% at 2 years, and 86.2% ± 2.1% at 3 years. A total of 51 secondary interventions (4 early, 47 late) were required in 38 patients (12%), with a cumulative risk of 4.2% ± 1.1% at 1 year, 7.6% ± 1.6% at 2 years, and 12.9% ± 2.2% at 3 years.ConclusionsTo our surprise, emergency endovascular aneurysm repair did not present with higher secondary intervention rate at mid-term follow-up
Long-Term Survival and Quality of Life After Fenestrated Endovascular Repair for Complex Abdominal Aortic Aneurysms
Objectives: Fenestrated endovascular repair (FEVAR) has become a widely used treatment option for complex abdominal aortic aneurysms (AAA) but long-term survival and quality of life (QoL) outcomes are scarce. This single center cohort study aims to evaluate both long-term survival and QoL after FEVAR.Methods: All juxtarenal and suprarenal AAA patients treated with FEVAR in a single-center between 2002 and 2016 were included. QoL scores, measured by the RAND 36-Item Short Form Survey (SF-36), were compared with baseline data of the SF-36 provided by RAND.Results: A total of 172 patients were included at a median follow-up of 5.9 years (IQR 3.0-8.8). Follow-up at 5 and 10 years post-FEVAR yielded survival rates of 59.9% and 18%, respectively. Younger patient age at surgery had a positive influence on 10-year survival and most patients died due to cardiovascular pathology. Emotional well-being was better in the research group as compared to baseline RAND SF-36 1.0 data (79.2 ± 12.4 vs 70.4 ± 22.0; P < 0.001). Physical functioning (50 (IQR 30–85) vs 70.6 ± 27.4; P = 0.007) and health change (51.6 ± 17.0 vs 59.1 ± 23.1; P = 0.020) were worse in the research group as compared to reference values.Conclusions: Long-term survival was 60% at 5-years follow-up, which is lower than reported in recent literature. An adjusted positive influence of younger age at surgery was found on long-term survival. This could have consequences for future treatment indication in complex AAA surgery but further large-scale validation is necessary.</p
Spin-Orbit Splitting in Non-Relativistic and Relativistic Self-Consistent Models
The splitting of single-particle energies between spin-orbit partners in
nuclei is examined in the framework of different self-consistent approachs,
non-relativistic as well as relativistic. Analytical expressions of spin-orbit
potentials are given for various cases. Proton spin-orbit splittings are
calculated along some isotopic chains (O, Ca, Sn) and they are compared with
existing data. It is found that the isotopic dependence of the relativistic
mean field predictions is similar to that of some Skyrme forces while the
relativistic Hartree-Fock approach leads to a very different dependence due to
the strong non-locality.Comment: 12 pages, RevTeX, 4 new figs.in .zip format, unchanged conclusions,
Phys. ReV.
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