23 research outputs found
A Search For Organic Molecules in Intermediate Redshift DLAs
There has been a renewed interest in searching for diffuse interstellar bands
(DIBs) due to their probable connection to organic molecules and, thus, their
possible link to life in the Universe. Our group is undertaking an extensive
search for DIBs in DLAs via QSO absorption-line systems. Six of our DLA targets
are presented here. Our equivalent width (EW) limits for the 5780 DIB line
strongly suggests that DIB abundance is below the Milky Way expected value or
that metallicity plays a large role in DIB strengths.Comment: 3 pages; 2 figures; presented at IAU 199; Probing Galaxies through
Quasar Absorption Line
Beyond the International Year of Astronomy: The Universe Discovery Guides
Developed for informal educators and their audiences, the 12 Universe Discovery Guides (UDGs, one per month) are adapted from the Discovery Guides that were developed for the International Year of Astronomy in 2009. The UDGs showcase education and public outreach resources from across more than 30 NASA astrophysics missions and programs. Via collaboration through scientist and educator partnerships, the UDGs aim to increase the impact of individual missions and programs, put their efforts into context, and extend their reach to new audiences. Each of the UDGs has a science topic, an interpretive story, a sky object to view with finding charts, hands-on activities, and connections to recent NASA science discoveries. The UDGs are modular; informal educators can take resources from the guides that they find most useful for their audiences. Attention is being given to audience needs, and field-testing is ongoing. The UDGs are available via downloadable PDFs
Visualization of brain microvasculature and blood flow in vivo: Feasibility study using confocal laser endomicroscopy
Objective: Qualitative and quantitative analyses of blood flow in normal and pathologic brain and spinal cord microvasculature were performed using confocal laser endomicroscopy (CLE). Methods: Blood flow in cortical, dural, and spinal cord microvasculature was assessed in vivo in swine. We assessed microvasculature under normal conditions and after vessel occlusion, brain injury due to cold or surgical trauma, and cardiac arrest. Tumor-associated microvasculature was assessed in vivo and ex vivo in 20 patients with gliomas. Results: We observed erythrocyte flow in vessels 5-500 µm in diameter. Thrombosis, flow arrest and redistribution, flow velocity changes, agglutination, and cells rolling were assessed in normal and injured brain tissue. Microvasculature in in vivo CLE images of gliomas was classified as normal in 68% and abnormal in 32% of vessels on the basis of morphological appearance. Dural lymphatic channels were discriminated from blood vessels. Microvasculature CLE imaging was possible for up to 30 minutes after a 1 mg/kg intravenous dose of fluorescein. Conclusions: CLE imaging allows assessment of cerebral and tumor microvasculature and blood flow alterations with subcellular resolution intraoperative imaging demonstrating precise details of real-time cell movements. Research and clinical scenarios may benefit from this novel intraoperative in vivo microscopic fluorescence imaging modality
Limits on Reddening and Gas-to-Dust Ratios for Seven Intermediate Redshift Damped Ly-alpha Absorbers from Diffuse Interstellar Bands
Original article can be found at: http://www.iop.org/EJ/journal/aj Copyright American Astronomical Society DOI: 10.1088/0004-6256/136/3/994 [Full text of this article is not available in the UHRA]Peer reviewe