Interstellar gas and dust in the young cluster IC 348

We have completed a multiband absorption- and emission-line study of a star embedded in the young cluster IC 348, to determine the environmental effect of star formation on the interstellar medium (ISM) local to the region. The hottest and youngest star in IC 348 is BD+31°643, a B5 V star which samples the inner bright nebular region. The nearby star o Per, which lies only 8 to the north and is thought to lie beyond IC 348, samples the gas and dust which has not been processed by very recent star formation. We speculate that the ISM throughout the region was originally the same as that currently seen toward o Per, but now the contrasting environmental conditions due to the recent star formation have led to marked differences in the atomic, molecular, and dust characteristics of IC 348. These contrasts include what we have termed a ``composite\u27\u27 UV extinction curve for BD+31°643, evidence for enhanced density and enhanced depletions within IC 348 and very different molecular abundances in the interstellar sightline to BD+31°643. Toward BD+31°643, we find a higher column density of CH, but lower CN and very much higher CH + than measured toward o Per. We conclude that the physical and chemical state of the gas and dust has been altered by local processes and conditions within IC 348. The characteristics of the ISM in IC 348, via our study of the star BD+31°643, closely resemble those seen toward Oph, another sight line passing through a bright nebular region. However, the stars are not as hot in IC 348 as in Ophiuchus, so their effect on the local ISM is not as severe

Interstellar gas and dust in the young cluster IC 348

We have completed a multiband absorption- and emission-line study of a star embedded in the young cluster IC 348, to determine the environmental effect of star formation on the interstellar medium (ISM) local to the region. The hottest and youngest star in IC 348 is BD+31°643, a B5 V star which samples the inner bright nebular region. The nearby star o Per, which lies only 8 to the north and is thought to lie beyond IC 348, samples the gas and dust which has not been processed by very recent star formation. We speculate that the ISM throughout the region was originally the same as that currently seen toward o Per, but now the contrasting environmental conditions due to the recent star formation have led to marked differences in the atomic, molecular, and dust characteristics of IC 348. These contrasts include what we have termed a ``composite\u27\u27 UV extinction curve for BD+31°643, evidence for enhanced density and enhanced depletions within IC 348 and very different molecular abundances in the interstellar sightline to BD+31°643. Toward BD+31°643, we find a higher column density of CH, but lower CN and very much higher CH + than measured toward o Per. We conclude that the physical and chemical state of the gas and dust has been altered by local processes and conditions within IC 348. The characteristics of the ISM in IC 348, via our study of the star BD+31°643, closely resemble those seen toward Oph, another sight line passing through a bright nebular region. However, the stars are not as hot in IC 348 as in Ophiuchus, so their effect on the local ISM is not as severe

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The Texas Earth and Space Science (TXESS) Revolution: A Model for the Delivery of Earth Science Professional Development to Minority-Serving Teachers

At the time of publication K.K. Ellins, E. Snow, H.C. Olson, M. Willis, and J. Olson were at the University of Texas Austin, E. Stocks and M.R. Odell were at the University of Texas at Tyler.The Texas Earth and Space Science (TXESS) Revolution was a 5-y teacher professional development project that aimed to increase teachers' content knowledge in Earth science and preparing them to teach a 12th-grade capstone Earth and Space Science course, which is new to the Texas curriculum. The National Science Foundation–supported project was designed around six principles that proved to be critical to in its success: (1) model best practices in workshop presentations, (2) use authentic Earth science data and cybertechnology to teach up-to-date content, (3) provide ongoing training to cohorts of learners over a 2-y period, (4) involve geoscience consortia and programs that can provide proven content for classrooms, (5) use ongoing evaluations to guide future workshops, and (6) provide opportunities for leadership development through participation in research and curriculum development projects. The project served 177 science teachers by supporting them with the pedagogical, technological, and scientific tools to teach modern geoscience. TXESS Revolution teachers directly impacted more than 29,000 students, of which about 69% are nonwhite, by exposing students in Texas to the geosciences and planting the seeds for them to pursue geoscience as a field of study. Using a train-the-trainer approach, TXESS Revolution teachers shared their professional development with other Texas teachers, strengthening Earth science education at all K–12 levels throughout the state, an impact that extends beyond preparation in Earth and space science.Petroleum and Geosystems Engineerin

Antibiotic resistance genes in swine manure slurry as affected by pit additives and facility disinfectants

Manure storage facilities are critical control points to reduce antibiotic resistance genes (ARGs) in swine manure slurry before the slurry is land applied. However, little is known about how exogenous chemicals entering the manure storage facilities may affect the fate of ARGs. The objective of this study was to analyze the impact of six commonly used pit additives and four facility disinfectants on the concentration of ARGs in swine manure slurry. Bench scale reactors, each containing approximately 50 L of liquid swine manure, were dosed with additives or disinfectants and were sampled for 40 days. Seven antibiotic resistance genes along with the intI1 gene and the 16S rRNA gene were monitored. Out of the six additives tested, Sludge Away significantly reduced the time-averaged absolute abundance of erm(C), erm(F), tet(Q), and the 16S rRNA gene as compared to the no additive control. Out of the four disinfectants tested, Tek-Trol significantly reduced the time-averaged absolute abundance of erm(B), erm(C), erm(F), intI1, tet(Q), and tet(X) than did the no-disinfectant control. According to Spearman\u27s rank correlation, three genes erm(F), tet(Q), and tet(X) showed a strong to perfectly positive correlation and the two genes erm(B) and tet(O) showed a moderate to strong correlation in both the additive and disinfectant tests. Overall, the disinfectants were more effective in controlling the absolute abundance of ARGs than were the pit additives

Optical Structure and Proper-Motion Age of the Oxygen-rich Supernova Remnant 1E 0102-7219 in the Small Magellanic Cloud

We present new optical emission-line images of the young SNR 1E 0102-7219 (E0102) in the SMC obtained with the HST Advanced Camera for Surveys (ACS). E0102 is a member of the oxygen-rich class of SNRs showing strong oxygen, neon , and other metal-line emissions in its optical and X-ray spectra, and an absence of H and He. The progenitor of E0102 may have been a Wolf-Rayet star that underwent considerable mass loss prior to exploding as a Type Ib/c or IIL/b SN. The ejecta in this SNR are fast-moving (V > 1000 km/s) and emit as they are compressed and heated in the reverse shock. In 2003, we obtained optical [O III], H-alpha, and continuum images with the ACS Wide Field Camera. The [O III] image captures the full velocity range of the ejecta, and shows considerable high-velocity emission projected in the middle of the SNR that was Doppler-shifted out of the narrow F502N bandpass of a previous Wide Field and Planetary Camera 2 image from 1995. Using these two epochs separated by ~8.5 years, we measure the transverse expansion of the ejecta around the outer rim in this SNR for the first time at visible wavelengths. From proper-motion measurements of 12 ejecta filaments, we estimate a mean expansion velocity for the bright ejecta of ~2000 km/s and an inferred kinematic age for the SNR of \~2050 +/- 600 years. The age we derive from HST data is about twice that inferred by Hughes et al.(2000) from X-ray data, though our 1-sigma error bars overlap. Our proper-motion age is consistent with an independent optical kinematic age derived by Eriksen et al.(2003) using spatially resolved [O III] radial-velocity data. We derive an expansion center that lies very close to X-ray and radio hotspots, which could indicate the presence of a compact remnant (neutron star or black hole).Comment: 28 pages, 8 figures. Accepted to the Astrophysical Journal, to appear in 20 April 2006 issue. Full resolution figures are posted at: http://stevenf.asu.edu/figure

Linking goniometer measurements to hyperspectral and multi-sensor imagery for retrieval of beach properties and coastal characterization

In June 2011, a multi-sensor airborne remote sensing campaign was flown at the Virginia Coast Reserve Long Term Ecological Research site with coordinated ground and water calibration and validation (cal/val) measurements. Remote sensing imagery acquired during the ten day exercise included hyperspectral imagery (CASI-1500), topographic LiDAR, and thermal infra-red imagery, all simultaneously from the same aircraft. Airborne synthetic aperture radar (SAR) data acquisition for a smaller subset of sites occurred in September 2011 (VCR\u2711). Focus areas for VCR\u2711 were properties of beaches and tidal flats and barrier island vegetation and, in the water column, shallow water bathymetry. On land, cal/val emphasized tidal flat and beach grain size distributions, density, moisture content, and other geotechnical properties such as shear and bearing strength (dynamic deflection modulus), which were related to hyperspectral BRDF measurements taken with the new NRL Goniometer for Outdoor Portable Hyperspectral Earth Reflectance (GOPHER). This builds on our earlier work at this site in 2007 related to beach properties and shallow water bathymetry. A priority for VCR\u2711 was to collect and model relationships between hyperspectral imagery, acquired from the aircraft at a variety of different phase angles, and geotechnical properties of beaches and tidal flats. One aspect of this effort was a demonstration that sand density differences are observable and consistent in reflectance spectra from GOPHER data, in CASI hyperspectral imagery, as well as in hyperspectral goniometer measurements conducted in our laboratory after VCR\u2711

Collaboration trumps homophily in urban mobile crowd-sourcing

National Research Foundation (NRF) Singapore under IDM Futures Funding Initiativ

A cluster randomised trial to assess the impact of clinical pathways on AMI management in rural Australian emergency departments

Background. People living in rural Australia are more likely to die in hospital following an acute myocardial infarction than those living in major cities. While several factors, including time taken to access hospital care, contribute to this risk, it is also partially attributable to the lower uptake of evidence-based guidelines for the administration of thrombolytic drugs in rural emergency departments where up to one-third of eligible patients do not receive this life-saving intervention. Clinical pathways have the potential to link evidence to practice by integrating guidelines into local systems, but their impact has been hampered by variable implementation strategies and sub-optimal research designs. The purpose of this study is to determine the impact of a five-step clinical pathways implementation process on the timely and efficient administration of thrombolytic drugs for acute myocardial infarctions managed in rural Australian emergency departments. Methods/Design. The design is a two-arm, cluster-randomised trial with rural hospital emergency departments that treat and do not routinely transfer acute myocardial infarction patients. Six rural hospitals in the state of Victoria will participate, with three in the intervention group and three in the control group. Intervention hospitals will participate in a five-step clinical pathway implementation process: engagement of clinicians, pathway development according to local resources and systems, reminders, education, and audit and feedback. Hospitals in the control group will each receive a hard copy of Australian national guidelines for chest pain and acute myocardial infarction management. Each group will include 90 cases to give a power of 80% at 5% significance level for the two primary outcome measures: proportion of those eligible for thrombolysis receiving the drug and time to delivery of thrombolytic drug. Discussion. Improved compliance with thrombolytic guidelines via clinical pathways will increase acute myocardial infarction survival rates in rural hospitals and thereby help to reduce rural-urban mortality inequalities. Such knowledge translation has the potential to be adapted for a range of clinical problems in a wide array of settings. Trial registration. Australia New Zealand Clinical Trials Registry code ACTRN12608000209392

The Cosmic Origins Spectrograph

The Cosmic Origins Spectrograph (COS) is a moderate-resolution spectrograph with unprecedented sensitivity that was installed into the Hubble Space Telescope (HST) in May 2009, during HST Servicing Mission 4 (STS-125). We present the design philosophy and summarize the key characteristics of the instrument that will be of interest to potential observers. For faint targets, with flux F(sub lambda) approximates 1.0 X 10(exp -14) ergs/s/cm2/Angstrom, COS can achieve comparable signal to noise (when compared to STIS echelle modes) in 1-2% of the observing time. This has led to a significant increase in the total data volume and data quality available to the community. For example, in the first 20 months of science operation (September 2009 - June 2011) the cumulative redshift pathlength of extragalactic sight lines sampled by COS is 9 times that sampled at moderate resolution in 19 previous years of Hubble observations. COS programs have observed 214 distinct lines of sight suitable for study of the intergalactic medium as of June 2011. COS has measured, for the first time with high reliability, broad Lya absorbers and Ne VIII in the intergalactic medium, and observed the HeII reionization epoch along multiple sightlines. COS has detected the first CO emission and absorption in the UV spectra of low-mass circumstellar disks at the epoch of giant planet formation, and detected multiple ionization states of metals in extra-solar planetary atmospheres. In the coming years, COS will continue its census of intergalactic gas, probe galactic and cosmic structure, and explore physics in our solar system and Galaxy