[Short-term outcomes of mechanical and hand-sewn laparoscopic one-anastomosis mini-gastric bypass]. / Sravnitel'naya otsenka blizhaishikh rezul'tatov laparoskopicheskogo minigastroshuntirovaniya s apparatnym i manual'nym sposobami formirovaniya gastroeyunoanastomoza.

OBJECTIVE: To evaluate the short-term outcomes of mechanical and hand-sewn laparoscopic one-anastomosis mini-gastric bypass. MATERIAL AND METHODS: There were 233 patients who underwent laparoscopic one-anastomosis mini-gastric bypass. Short-term results were analyzed in groups of mechanical (the first group, n=108) and hand-sewn (the second group, n=125) gastrojejunostomy. No significant between-group differences in baseline data were detected (demographic characteristics, body mass index, comorbidity and previous abdominal surgeries). RESULTS: Surgery time and blood loss were similar in both groups. Intraoperative morbidity was 7.2-10.2% (p=0.485). All complications required no surgical conversion (Satava-Kazaryan grade I). Overall postoperative morbidity was 16.0-21.3% (p=0.314). Most events corresponded to Accordion grade I and had no significant effect on hospital-stay. CONCLUSION: This study revealed no significant differences in short-term outcomes after laparoscopic one-anastomosis gastric bypass with mechanical and hand-sewn gastrojejunostomy. Further study of long-term clinical outcomes is necessary.

Enhanced sputtering yields from single-ion impacts on gold nanorods.

Sputtering yields, enhanced by more than an order of magnitude, have been observed for 80 keV Xe ion irradiation of monocrystalline Au nanorods. Yields are in the range 100-1900 atoms/ion compared with values for a flat surface of ≈50. This enhancement results in part from the proximity of collision cascades and ensuing thermal spikes to the nanorod surfaces. Molecular dynamic modeling reveals that the range of incident angles occurring for irradiation of nanorods and the larger number of atoms in "explosively ejected" atomic clusters make a significant contribution to the enhanced yield.

Modeling of high-fluence irradiation of amorphous Si and crystalline Al by linearly focused Ar ions.

Long time ion irradiation of surfaces under tilted incidence causes formation of regular nanostructures known as surface ripples. The nature of mechanisms leading to ripples is still not clear, this is why computational methods can shed the light on such a complex phenomenon and help to understand which surface processes are mainly responsible for it. In this work, we analyse the surface response of two materials, a semiconductor (silicon) and a metal (aluminium) under irradiation with the 250 eV and 1000 eV Ar ions focused at 70° from the normal to the surface. We simulate consecutive ion impacts by the means of molecular dynamics to investigate the effect on ripple formation. We find that the redistribution mechanism seems to be the main creator of ripples in amorphous materials, while the erosion mechanism is the leading origin for the pattern formation in crystalline metals.

Effects of crystallographic and geometric orientation on ion beam sputtering of gold nanorods.

Nanostructures may be exposed to irradiation during their manufacture, their engineering and whilst in-service. The consequences of such bombardment can be vastly different from those seen in the bulk. In this paper, we combine transmission electron microscopy with in situ ion irradiation with complementary computer modelling techniques to explore the physics governing the effects of 1.7 MeV Au ions on gold nanorods. Phenomena surrounding the sputtering and associated morphological changes caused by the ion irradiation have been explored. In both the experiments and the simulations, large variations in the sputter yields from individual nanorods were observed. These sputter yields have been shown to correlate with the strength of channelling directions close to the direction in which the ion beam was incident. Craters decorated by ejecta blankets were found to form due to cluster emission thus explaining the high sputter yields.