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We report our measured values for the sum of single and double charge transfer rate coefficients between ³He2+ and H2, CH4, N2 and CO. Our values are 2.4 ± 0.2 × 10-9 cm³ s-1 for H2, 6.3 ± 0.9 × 10-9 cm³ s-1 for CH4, 4.0 ± 0.3 × 10-9 cm³ s-1 for N2 and 4.7 ± 0.4 × 10-9 cm³ s-1 for CO. The values are obtained at equivalent temperatures of 1200-2400 K. [ABSTRACT FROM AUTHOR]

Background: Microscopic tumor involvement (R1) in different surgical resection margins after pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC) has been debated.Methods: Clinico-pathological data for 258 patients who underwent PD between 2001 and 2010 were retrieved from a prospective database. The rates of R1 resection in the circumferential resection margin (pancreatic transection, medial, posterior, and anterior surfaces) and their prognostic influence on survival were assessed.Results: For PDAC, the R1 rate was 57.1% (48/84) for any margin, 31.0% (26/84) for anterior surface, 42.9% (36/84) for posterior surface, 29.8% (25/84) for medial margin, and 7.1% (3/84) for pancreatic transection margin. Overall and disease-free survival for R1 resections were significantly worse than those for R0 resection (17.2 vs. 28.7 months, P = 0.007 and 12.3 vs. 21.0 months, P = 0.019, respectively). For individual margins, only medial positivity had a significant impact on survival (13.8 vs. 28.0 months, P < 0.001), as opposed to involvement in the anterior (19.7 vs. 23.3 months, P = 0.187) or posterior margin (17.5 vs. 24.2 months, P = 0.104). Multivariate analysis demonstrated R0 medial margin was an independent prognostic factor (P = 0.002, HR = 0.381; 95% CI 0.207-0.701).Conclusion: The medial surgical resection margin is the most important after PD for PDAC, and an R1 resection here predicts poor survival. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the immediate and midterm outcomes of percutaneous endovascular repair of thoracic and abdominal aortic pathology. Between December 2003 and June 2005, 21 patients (mean age: 60.4 +/- 17.1 years; 15 males, 6 females) underwent endovascular stent-graft insertion for thoracic (n = 13) or abdominal aortic (n = 8) pathology. Preprocedural computed tomographic angiography (CTA) was performed to assess the suitability of aorto-iliac and common femoral artery (CFA) anatomy, including the degree of CFA calcification, for total percutaneous aortic stent-graft repair. Percutaneous access was used for the introduction of 18- to 26-Fr delivery devices. A 'preclose' closure technique using two Perclose suture devices (Perclose A-T; Abbott Vascular) was used in all cases. Data were prospectively collected. Each CFA puncture site was assessed via clinical examination and CTA at 1, 6, and 12 months, followed by annual review thereafter. Minimum follow-up was 36 months. Outcome measures evaluated were rates of technical success, conversion to open surgical repair, complications, and late incidence of arterial stenosis at the site of Perclose suture deployment. A total of 58 Perclose devices were used to close 29 femoral arteriotomies. Outer diameters of stent-graft delivery devices used were 18 Fr (n = 5), 20 Fr (n = 3), 22 Fr (n = 4), 24 Fr (n = 15), and 26 Fr (n = 2). Percutaneous closure was successful in 96.6% (28/29) of arteriotomies. Conversion to surgical repair was required at one access site (3.4%). Mean follow-up was 50 +/- 8 months. No late complications were observed. By CT criteria, no patient developed a >50% reduction in CFA caliber at the site of Perclose deployment during the study period. In conclusion, percutaneous aortic stent-graft insertion can be safely performed, with a low risk of both immediate and midterm access-related complications. [ABSTRACT FROM AUTHOR]

The rate coefficient of resonant charge transfer between 3He2 + and 4He, at energies below 1 eV, was measured using an rf ion trap and time-of-flight mass spectrometry. We obtain a resonant charge transfer rate coefficient of 5.9 ± 0.6 × 10−10 cm3 s−1 at an equivalent temperature of 1200 K. The measured value compares favourably to existing calculations. This measurement extends our knowledge to a broader spectrum of energies as it provides information on the rate coefficients at a low energy and adds to our understanding of the charge transfer process of 3He2 +, α-particles, with He encountered in astrophysics and nuclear fusion. [ABSTRACT FROM AUTHOR]