Human genomic structural variation (SV) is significant factor in genome complexity, and thus has substantial implications to the cause, development and progression of genetic diseases. These SVs, ranging in size of 1kbp-1Mbp, are challenging to assess with current technologies. As such, we have developed a commercial system (nanoAnalyzer® 1000) for the rapid linear analysis of genomes at single-molecule level.

The core of our system is a nanofluidic chip consisting of an array of channels with a diameter less than 100 nm, nanofabricated on the surface of a silicon substrate. Thousands of unamplified genomic DNA molecules of 100’s kbps to several Mbps can be isolated and linearly streamed into the array for analysis in a parallel fashion. Fluorescently labeled sequence-specific signatures can then be identified and aligned to reference patterns at high resolution with custom software. This automated, multi-color imaging platform will enable a wide range of applications, such as accurate sequencing assembly, discovering genome structural variations, and uncovering epigenomic content. Nanochannel arrays promise to substantially lower the barriers of entry for single-molecule DNA analysis for scientists and clinicians, greatly impacting the advancement of molecular diagnostics, personalized medicine, and biomedical research.

Extended abstract of a paper presented at Microscopy and Microanalysis 2005 in Honolulu, Hawaii, USA, July 31--August 4, 2005

We present results from photometric and spectroscopic survey of giant stars in the Leo I dwarf spheroidal galaxy. We find compelling evidence that this galaxy has been tidally disrupted.

Radial velocities of 20 stars members of young clusters and associations located in the inter-Cloud region within 2h < R.A. < 5h tend to be lower than the HI velocities in the same direction. The stellar velocities do not show a pronounced velocity gradiant as observed for the HI from the SMC to the LMC. This suggests that the stellar components belong to the SMC wing. Our photometry and spectroscopy support the view that one of the stars at 4h20m is a foreground HB star.

We present deep CCD photometry of three associations lying between the Magellanic Clouds and sitting on the HI ridge. ZAMS fittings show that these clusters are located at the distance of the Clouds. Furthermore, a slight distance gradient is observed. Main sequences matched to isochrones reveal that these aggregates are very young, no more than 108 years old. An age difference from east to west is also suggested.

1. Two studies were performed to determine the effects of acid stress and ovariectomy on bone metabolism in young rats. In Expt 1, eighteen female weanling Sprague-Dawley-descended rats were ovariectomized, placed in one of three dietary groups and given a diet containing (g/kg): 6 calcium and 3, 6 or 12 phosphorus for 10 weeks. In Expt 2, thirty-two female weanling Sprague-Dawley-descended rats were ovariectomized, and thirty-two were left intact. Eight rats from each group were given a diet containing (g/kg): 6 Ca and 3 P, 12 P, 3 P+1 S or 3 P+20 ammonium chloride for 10 weeks.

2. Feeding diets containing 12 g P/kg resulted in decreased serum Ca and increased urinary P with no changes in femur composition. Feeding high-sulphate and ammonium chloride diets resulted in increased urinary Ca and, when combined with ovariectomy, lower femur Ca and P with no changes in femur hydroxyproline or hexosamines.

3. The findings reflect the more rapid turnover of the amorphous calcium phosphate salts found in greater amounts in bones of younger animals than for more stable apatitic crystals that predominate in bones of older animals.

The techniques and procedures of time-series monitoring and Fourier analysis which are used at Cerro Tololo to search for luminosity variations in white dwarfs are summarized. Further null results from this program, which are applicable to the problem of defining the region of white-dwarf variability in the HR-diagram, are considered; and the properties of the four known variables are reviewed as possible archetypes of a group.

The telescope used for identification of X-ray sources at the Cerro Tololo Inter-American Observatory is the Curtis Schmidt Telescope. This telescope is located at Tololo by agreement with the University of Michigan. The field of the telescope is 5° × 5° and its correcting aspheric plate has negligible chromatic aberration over the range 3200 to 10000 Å. This latter feature makes it an ideal instrument for multicolor survey work.