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Grand Rapids, MI, United States

Galvin T.J.,University of Western Sydney | Filipovic M.D.,University of Western Sydney | Crawford E.J.,University of Western Sydney | Wong G.,University of Western Sydney | And 12 more authors.
Astrophysics and Space Science | Year: 2012

A series of new radio-continuum (λ=20 cm) mosaic images focused on the NGC 300 galactic system were produced using archived observational data from the VLA and/or ATCA. These new images are both very sensitive (rms =60 μJy) and feature high angular resolution (<10 ″). The most prominent new feature is the galaxy's extended radio-continuum emission, which does not match its optical appearance. Using these newly created images a number of previously unidentified discrete sources have been discovered. Furthermore, we demonstrate that a joint deconvolution approach to imaging this complete data-set is inferior when compared to an immerge approach. © 2012 Springer Science+Business Media B.V.

Laureto P.J.,Western Michigan University | Laureto P.J.,Grand Rapids Community College | Barkman T.J.,Western Michigan University
Systematic Botany | Year: 2011

Solidago houghtonii Torrey & A. Gray ex Gray is a federally threatened polyploid plant species likely of hybrid origin. Several hypothesized combinations of parental species have been suggested but none have been phylogenetically tested. Additionally, it is unclear whether the species is of single or polytopic origin. To study the evolutionary history of S. houghtonii we sequenced four noncoding cpDNA loci (accD-psaI, psbA-trnH, trnL-trnF, rps16-trnQ), and the ITS and 3′ETS regions for four accessions of S. houghtonii, which span its geographic range, and 25 other species of Solidago including all sympatric species. Polymorphisms within the direct nrDNA sequences of all S. houghtonii accessions indicated the presence of multiple homoeologue types. These were separated by molecular cloning of the 3055 bp 3′ETS-ITS region, allowing us to positively link the ETS and ITS homoeologue types. Phylogenetic analyses of the nuclear and chloroplast datasets revealed incongruent topologies. Analysis of cloned nrDNA sequence data indicated that S. riddellii, S. ptarmicoides, and S. ohioensis have contributed to the nuclear genome of S. houghtonii. Analysis of cpDNA sequence data revealed the presence of multiple insertions/deletions that are shared by all accessions. The unique pattern of cpDNA indels was also recovered in S. gigantea. Phylogenetic analysis of the cpDNA sequence data and coded indels indicate S. gigantea is the maternal genome donor. However, we did not recover a S. gigantea nrDNA sequence type. Taken together, these data reveal both a single origin and a complex pattern of reticulation that is consistent not only with the hypothesized allohexaploid nature of this species, but also with chloroplast capture of cpDNA from an unexpected source through introgression. © Copyright 2011 by the American Society of Plant Taxonomists.

Millar W.C.,James Cook University | Millar W.C.,Grand Rapids Community College | White G.L.,University of Western Sydney | Filipovic M.D.,James Cook University | And 5 more authors.
Astrophysics and Space Science | Year: 2011

We present moderate-resolution (<5 Å) long-slit optical spectra of 51 nebular objects in the nearby Sculptor Group galaxy NGC 300 obtained with the 2. 3 meter Advanced Technology Telescope at Siding Spring Observatory, Australia. Adopting the criterion of [S ii]Total:Hα≥0. 4 to confirm supernova remnants (SNRs) from optical spectra, we find that of 28 objects previously proposed as SNRs from optical observations, 22 meet this criterion with six showing [S ii]Total:Hα of less than 0. 4. Of 27 objects suggested as SNRs from radio data, four are associated with the 28 previously proposed SNRs. Of these four, three (included in the 22 above) meet the criterion. In all, 22 of the 51 nebular objects meet the [S ii]Total:Hα criterion as SNRs while the nature of the remaining 29 objects remains undetermined by these observations. © 2010 Springer Science+Business Media B.V.

Millar W.C.,James Cook University | Millar W.C.,Grand Rapids Community College | White G.L.,Charles Sturt University | Filipovic M.D.,James Cook University | Filipovic M.D.,University of Western Sydney
Serbian Astronomical Journal | Year: 2012

We present the results of a study of observational and identification techniques used for surveys and spectroscopy of candidate supernova remnants (SNRs) in the Sculptor Group galaxy NGC300. The goal of this study was to investigate the reliability of using [S II]:Hα ≥ 0.4 in optical SNR surveys and spectra as an identifying feature of extra-galactic SNRs (egSNRs), and also to investigate the effectiveness of the observing techniques (which are hampered by seeing conditions and telescope pointing errors) using this criterion in egSNR surveys and spectrographs. This study is based on original observations of these objects and archival data obtained from the Hubble Space Telescope which contained images of some of the candidate SNRs in NGC300. We found that the reliability of spectral techniques may be questionable and very high-resolution images may be needed to confirm a valid identification of some egSNRs.

Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 166.21K | Year: 2012

The goals of this project include increased student knowledge of gas chromatography-mass spectrometry (GC-MS) by adding hands-on laboratory experiences to chemistry courses and independent study projects at Grand Rapids Community College, development of GC-MS expertise for community college and high school faculty, and instrumentation experiences for high school students. Developed materials reflect workforce needs, delivered using a constructivist approach. The intellectual merit is the development of broadly applicable processes for integrating GC-MS into community college laboratory course curricula to enhance learning and interest. Professional development and summer camp opportunities enhance high school faculty and students understanding of GC-MS while demonstrating practical connections between science and technology, and serve as a model for high school-community college partnerships. Broader impacts include better prepared students through engaging hands-on science education, enhanced educational infrastructure, and a close partnership with local high schools.

The independent evaluation encompasses formative assessment of instructor content knowledge and engagement, coupled with assessment of student learning gains and attitudes toward science through review of course work, interviews and focus groups.

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