The authors have developed a method to produce a microbeam of slow highly charged ions based on a self-organized charge-up inside a tapered glass capillary. A transmission of 8 keV Ar 8+ beam through the capillary 5 cm long with 800/ 24 m inlet/outlet inner diameters was observed stably for more than 1200 s. The transmitted beam had the same size as the outlet with a beam density enhancement of approximately 10 and a divergence of ±5 mrad. The initial beam was guided through a capillary tilted by as large as ±100 mrad, and it still kept the incident charge.

Sex chromosomes are particularly interesting regions of the genome for both molecular genetics and evolutionary studies; yet, for most species, we lack basic information, such as the gene order along the chromosome. Because they lack recombination, Y-linked genes cannot be mapped genetically, leaving physical mapping as the only option for establishing the extent of synteny and homology with the X chromosome. Here, we developed a novel and general method for deletion mapping of non-recombining regions by solving “the travelling salesman problem”, and evaluate its accuracy using simulated datasets. Unlike the existing radiation hybrid approach, this method allows us to combine deletion mutants from different experiments and sources. We applied our method to a set of newly generated deletion mutants in the dioecious plant Silene latifolia and refined the locations of the sex-determining loci on its Y chromosome map.

The transmission of highly charged ions through nanocapillaries in insulating polyethylene terephthalate ͑PET͒ polymers was investigated. In experiments at laboratories in RIKEN ͑Japan͒ and HMI ͑Germany͒ different detection methods were applied to study the ion current dependence in a wide range covering two orders of magnitude. At HMI an electrostatic ion spectrometer was used and at RIKEN a two-dimensional position sensitive detector was implemented. New PET samples with parallel capillaries and low density were manufactured. For tilted capillaries, the ions are guided along the capillary axis, since the majority of ions are deflected in a charge patch created in the capillary entrance. The results provide insights into the mechanisms of capillary guiding. The fraction of transmitted ions was found to be nearly independent on the incident ion current indicating a sudden increase in the discharge current depleting the entrance charge patch. The experimental results were well-reproduced by model calculations based on a nonlinear ͑exponential͒ expression for the discharge current.

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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 ϳMeV He ion beam from such a capillary having 10 m outlet diameter inactivated a selected volume ͑ϳ m 3 ͒ of fluorescent molecules located in a HeLa cell nucleus.