Production of a microbeam of slow highly charged ions with a tapered glass capillary

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Ion irradiation in liquid of μm3 region for cell surgery

We present here a cell surgery scheme involving selective inactivation or disruption of cellular structures. Energetic ions are injected into a cell through a tapered glass capillary like a microinjection method. A slight but essential difference from microinjection is that a thin window is prepared at the outlet so that no liquid material can flow in or back through the outlet while still allowing energetic ions to penetrate into the cell. An ∼ MeV He ion beam from such a capillary having 10 μm outlet diameter inactivated a selected volume ( ∼ μm3) of fluorescent molecules located in a HeLa cell nucleus

Risk Factors for Bleeding After Endoscopic Submucosal Dissection for Gastric Cancer in Elderly Patients Older Than 80 Years in Japan.

Introduction:As the aging of people in a society advances, the number of elderly patients older than 80 years in Japan with gastric cancer continues to increase. Although delayed ulcer bleeding is a major adverse event after endoscopic submucosal dissection (ESD), little is known about characteristic risk factors for bleeding in elderly patients undergoing ESD. This study aimed to evaluate risk factors for delayed bleeding after ESD for gastric cancer in elderly patients older than 80 years.Methods:We retrospectively evaluated the incidence of delayed bleeding after ESD in 10,320 patients with early-stage gastric cancer resected by ESD between November 2013 and January 2016 at 33 Japanese institutions and investigated risk factors for delayed bleeding in elderly patients older than 80 years.Results:The incidence of delayed bleeding in elderly patients older than 80 years was 5.7% (95% confidence interval [CI]: 4.6%-6.9%, 95/1,675), which was significantly higher than that in nonelderly (older than 20 years and younger than 80 years) patients (4.5%, 4.1%-5.0%, 393/8,645). Predictive factors for ESD-associated bleeding differed between nonelderly and elderly patients. On multivariate analysis of predictive factors at the time of treatment, risk factors in elderly patients were hemodialysis (odds ratio: 4.591, 95% CI: 2.056-10.248, P < 0.001) and warfarin use (odds ratio: 4.783, 95% CI: 1.689-13.540, P = 0.003).Discussion:This multicenter study found that the incidence of delayed bleeding after ESD in Japanese patients older than 80 years was high, especially in patients receiving hemodialysis and taking warfarin. Management of ESD to prevent delayed bleeding requires particular care in patients older than 80 years

2MeV-He ion channeling studies of MOVPE-grown GaInNAs single quantum wells

The channeling technique of 2 MeV-He+ ions is applied to analyze the lattice structure of GaInNAs quantum wells sandwiched by GaAs barrier layers. The structure-sensitive channeling measurements reveal that the GaInNAs layer contains significant lattice distortion even after post-growth annealing at high temperatures. However, there exist no well-defined point defects such as tetrahedral interstitials. Our results suggest that the interstitial In atoms diffuse by annealing effect and we roughly estimate that the fraction of interstitial In atoms is reduced by not, vert, similar10% after annealing. Therefore, we demonstrate that the drastic improvement of the optical characteristics originates from the In diffusion by the annealing.journal articl

In-air PIXE analysis by means of glass capillary optics

A novel technique to introduce high energy ion beams to atmospheric environment is presented, which enables in-air PIXE measurements. Slightly tapered glass capillary optics is applied to work as a differential pumping orifice as well as a focusing lens. The flux intensity is enhanced by at least one order of magnitude due to the focusing effect. Using capillaries of 10–20 μm outlet diameters, we obtain several hundreds pA of 4 MeV He2+ ion beam and apply it to PIXE analysis of the seabed sludge without any sample treatments. A comparison of spectra between wet and dry sludge samples suggests the usefulness of our new technique