480 research outputs found

    KECK HIRES Spectroscopy of APM 08279+5255

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    With an optical R-band magnitude of 15.2, the recently discovered z=3.911 BAL quasar APM 08279+5255 is an exceptionally bright high redshift source. Its brightness has allowed us to acquire a high signal-to-noise ratio (~100), high resolution (~6 km/s) spectrum using the HIRES echelle spectrograph on the 10-m Keck I telescope. Given the quality of the data, these observations provide an unprecedented view of associated and intervening absorption systems. Here we announce the availability of this spectrum to the general astronomical community and present a brief analysis of some of its main features.Comment: 21 pages including 5 figures. Accepted for publication by PAS

    Information Acquisition Differences between Experienced and Novice Time Trial Cyclists

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    Purpose: To use eye-tracking technology to directly compare information acquisition behavior of experienced and novice cyclists during a self-paced 10 mile (16.1 km) time-trial. Method: Two groups of novice (N=10) and experienced cyclists (N=10) performed a 10-mile self-paced time-trial (TT) on two separate occasions during which a number of feedback variables (speed, distance, power output, cadence, heart rate, and time) were projected within their view. A large RPE scale was also presented next to the projected information and participants. Participants were fitted with a head-mounted eye-tracker and heart rate monitor. Results: Experienced cyclists performed both time-trials quicker than novices (F1,18=6.8, P=.018) during which they primarily looked at speed (9 of 10 participants) whereas novices primarily looked at distance (6 of 10 participants). Experienced cyclists looked at primary information for longer than novices across the whole time-trial (24.5+/-4.2% vs. 34.2+/-6.1%, t18=4.2, P<0.001) and less frequently than novices during the last quarter of the time-trial (49+/-19 vs. 80+/-32, t18=-2.6, P=0.009). The most common combination of primary and secondary information looked at by experienced cyclists was speed and distance respectively. Looking at ten different primary-secondary feedback permutations, the novices were less consistent than the experienced cyclists in their information acquisition behavior. Conclusion: This study challenges the importance placed on knowledge of the endpoint to pacing in previous models, especially for experienced cyclists for whom distance feedback was looked at secondary to, but in conjunction with, information about speed. Novice cyclists have a greater dependence upon distance feedback, which they look at for shorter and more frequent periods of time than the experienced cyclists. Experienced cyclists are more selective and consistent in attention to feedback during time-trial cycling

    Integrated Active Fire Retrievals and Biomass Burning Emissions Using Complementary Near-Coincident Ground, Airborne and Spaceborne Sensor Data

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    Ground, airborne and spaceborne data were collected for a 450 ha prescribed fire implemented on 18 October 2011 at the Henry W. Coe State Park in California. The integration of various data elements allowed near coincident active fire retrievals to be estimated. The Autonomous Modular Sensor-Wildfire (AMS) airborne multispectral imaging system was used as a bridge between ground and spaceborne data sets providing high quality reference information to support satellite fire retrieval error analyses and fire emissions estimates. We found excellent agreement between peak fire radiant heat flux data (less than 1% error) derived from near-coincident ground radiometers and AMS. Both MODIS and GOES imager active fire products were negatively influenced by the presence of thick smoke, which was misclassified as cloud by their algorithms, leading to the omission of fire pixels beneath the smoke, and resulting in the underestimation of their retrieved fire radiative power (FRP) values for the burn plot, compared to the reference airborne data. Agreement between airborne and spaceborne FRP data improved significantly after correction for omission errors and atmospheric attenuation, resulting in as low as 5 difference between AquaMODIS and AMS. Use of in situ fuel and fire energy estimates in combination with a collection of AMS, MODIS, and GOES FRP retrievals provided a fuel consumption factor of 0.261 kg per MJ, total energy release of 14.5 x 10(exp 6) MJ, and total fuel consumption of 3.8 x 10(exp 6) kg. Fire emissions were calculated using two separate techniques, resulting in as low as 15 difference for various specie

    The Chandra Multi-Wavelength Project: Optical Spectroscopy and the Broadband Spectral Energy Distributions of X-ray Selected AGN

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    From optical spectroscopy of X-ray sources observed as part of ChaMP, we present redshifts and classifications for a total of 1569 Chandra sources from our targeted spectroscopic follow up using the FLWO, SAAO, WIYN, CTIO, KPNO, Magellan, MMT and Gemini telescopes, and from archival SDSS spectroscopy. We classify the optical counterparts as 50% BLAGN, 16% NELG, 14% ALG, and 20% stars. We detect QSOs out to z~5.5 and galaxies out to z~3. We have compiled extensive photometry from X-ray to radio bands. Together with our spectroscopic information, this enables us to derive detailed SEDs for our extragalactic sources. We fit a variety of templates to determine bolometric luminosities, and to constrain AGN and starburst components where both are present. While ~58% of X-ray Seyferts require a starburst event to fit observed photometry only 26% of the X-ray QSO population appear to have some kind of star formation contribution. This is significantly lower than for the Seyferts, especially if we take into account torus contamination at z>1 where the majority of our X-ray QSOs lie. In addition, we observe a rapid drop of the percentage of starburst contribution as X-ray luminosity increases. This is consistent with the quenching of star formation by powerful QSOs, as predicted by the merger model, or with a time lag between the peak of star formation and QSO activity. We have tested the hypothesis that there should be a strong connection between X-ray obscuration and star-formation but we do not find any association between X-ray column density and star formation rate both in the general population or the star-forming X-ray Seyferts. Our large compilation also allows us to report here the identification of 81 XBONG, 78 z>3 X-ray sources and 8 Type-2 QSO candidates. Also we have identified the highest redshift (z=5.4135) X-ray selected QSO with optical spectroscopy.Comment: 17 pages, 16 figures, accepted for publication in ApJS. Full data table and README file can be found online at http://hea-www.harvard.edu/~pgreen/Papers.htm

    Information acquisition differences between experienced and novice time trial cyclists

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    Purpose: To use eye-tracking technology to directly compare information acquisition behavior of experienced and novice cyclists during a self-paced 10 mile (16.1 km) time-trial. Method: Two groups of novice (N=10) and experienced cyclists (N=10) performed a 10-mile self-paced time-trial (TT) on two separate occasions during which a number of feedback variables (speed, distance, power output, cadence, heart rate, and time) were projected within their view. A large RPE scale was also presented next to the projected information and participants. Participants were fitted with a head-mounted eye32 tracker and heart rate monitor. Results: Experienced cyclists performed both time-trials quicker than novices (F1,18=6.8, P=.018) during which they primarily looked at speed (9 of 10 participants) whereas novices primarily looked at distance (6 of 10 participants). Experienced cyclists looked at primary information for longer than novices across the whole time-trial (24.5±4.2% vs. 34.2±6.1%, t18=4.2, P<0.001) and less frequently than novices during the last quarter of the time-trial (49±19 vs. 80±32, t18=-2.6, P=0.009). The most common combination of primary and secondary information looked at by experienced cyclists was speed and distance respectively. Looking at ten different primary-secondary feedback permutations, the novices were less consistent than the experienced cyclists in their information acquisition behavior. Conclusion: This study challenges the importance placed on knowledge of the endpoint to pacing in previous models, especially for experienced cyclists for whom distance feedback was looked at secondary to, but in conjunction with, information about speed. Novice cyclists have a greater dependence upon distance feedback, which they look at for shorter and more frequent periods of time than the experienced cyclists. Experienced cyclists are more selective and consistent in attention to feedback during time-trial cycling

    Constraints on the Universal CIV Mass Density at z~6 from Early IR Spectra Obtained with the Magellan FIRE Spectrograph

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    We present a new determination of the intergalactic CIV mass density at 4.3 < z < 6.3. Our constraints are derived from high signal-to-noise spectra of seven quasars at z > 5.8 obtained with the newly commissioned FIRE spectrograph on the Magellan Baade telescope, coupled with six observations of northern objects taken from the literature. We confirm the presence of a downturn in the CIV abundance at =5.66 by a factor of 4.1 relative to its value at =4.96, as measured in the same sightlines. In the FIRE sample, a strong system previously reported in the literature as CIV at z=5.82 is re-identified as MgII at z=2.78, leading to a substantial downward revision in ΩCIV\Omega_{CIV} for these prior studies. Additionally we confirm the presence of at least two systems with low-ionization CII, SiII, and OI absorption but relatively weak signal from CIV. The latter systems systems may be of interest if the downward trend in ΩCIV\Omega_{CIV} at high redshift is driven in part by ionization effects.Comment: 14 pages, 6 figures, 2 tables. Submitted to Ap

    Bio-psychosocial determinants of cardiovascular disease in a rural population on Crete, Greece: formulating a hypothesis and designing the SPILI-III study

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    Background: In 1988, the SPILI project was established in order to evaluate the cardiovascular disease (CVD) risk profile of the inhabitants of Spili, in rural Crete, Greece. The first reports from this project revealed that against the unfavourable risk factors’ profile observed, only a few men with a previous myocardial infarction were encountered. A follow-up study (SPILI II) was performed twelve years after the initial examination, and the unfavourable cardiovascular risk profile was re-confirmed. Presentation of the Hypothesis: This paper presents a hypothesis formulated on the basis of previous research to investigate if dynamic psycho-social determinants, including social coherence of the local community, religiosity and spirituality, are protective against the development of coronary heart disease in a well-defined population. Testing the Hypothesis: A follow-up examination of this Cretan cohort is currently being performed to assess the link between psychosocial factors and CVD. Psychosocial factors including sense of control, religiosity and spirituality are assessed in together with conventional CVD risk factors. Smoking and alcohol consumption, as well as dietary habits and activity levels are recorded. Oxidative stress and inflammatory markers, as well as ultrasound measurement of carotid intima media thickness, a preclinical marker of atherosclerosis, will also be measured. Implications of the hypothesis tested: The issue of the cardio-protective effect of psycho-social factors would be revisited based on the results of this Cretan cohort; nevertheless, further research is needed across different subpopulations in order to establish a definite relationship. A comprehensive approach based on the aspects of biosocial life may result in more accurate CVD risk management

    Exile Vol. XXXIX No. 1

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    Title Page by Ellen Gurley \u2793 i Epigraph by Ezra Poind ii Table of Contents iii-iv Remaining a Soldier by Kristin Kruse \u2793 1-2 Vietnam War Memorial by Brooke MacKaye 3 We both ride in back by Chris Macaluso \u2793 4 Artwork by Jamie Oliver \u2794 5 Liberal Dirge #1 by Charis Brummitt \u2796 6-7 Artwork (anonymous) 7 Two ex-lovers and a dirty glass door by Chris Macaluso \u2793 8 The Salt of the Air by Kristen Padden \u2793 9-12 Artwork (anonymous) 13 Artwork by Ellen Gurley \u2793 14 Sun-Child by Jen Rudgers \u2796 15 Crazy Horse by Kevin Nix \u2794 16 The Fall of the Western Field by Rich Croft \u2793 17 In the Closet by Beth Widmaier \u2795 18 Winter Strawberries by Katy Rudder \u2793 19 Still Life (anonymous) 19 For This and Much Beyond This Poem by Matt Wanat \u2795 20-21 Artwork by Peggy Ryan \u2793 22 The Cycle Repeats: Apathy by Ishak Kang \u2793 23 The Judge by Ellen Gurley \u2793 24 Pear Colored by Erin Dempsey \u2793 25-26 4-Square by Trey Dunham \u2794 27 Artwork by Jamie Oliver \u2794 28 Ink & Heroine by Rich Croft \u2793 29 Figments by Craig Bowers \u2793 30-31 Malfi Coast (anonymous) 31 Suzanne (anonymous) 32 Hey Stella by Carey Chistie \u2795 33 Turning Leaves by Erin Lott \u2796 34-35 Reclining Nude (anonymous) 35 Blazon by Matt Wanat \u2795 36-37 Artwork by Holly Aikens \u2793 38 Awake by A. Fair \u2796 39 Dell the Barber by Kevin Nix \u2795 40 Artwork by Holly Aikens \u2793 40 Tree House by Katy Rudder \u2793 41-46 Jailbait by Ellison J. Stind \u2795 47 Mother by Charis Brummitt \u2796 48-49 Artwork by Bess Hammer \u2795 49 Private Origami by Trey Dunham \u2794 50 Among the Tendrils of Sleep by J. Trevett Allen \u2795 51 Poet of the Unforgiven by Carey Christie \u2795 52 Stuntman Steve by Andrew Zobay \u2793 53 sculpture by Lily Streett \u2794 53 Wonderings of an Adopted Son by Andy Heckert \u2793 54-55 Artwork by Holly Aikens \u2793 55 Odd Binge by C. N. Polumbus \u2793 56-57 Artwork by Holly Aikens \u2793 57 Artwork by Peggy Ryan \u2793; untitled by Jennifer Wendell \u2794 (superimposed) 58 Shadows of Pearl by Travis Brady \u2793 59-60 October/Rt. 161 by Annette Gallagher 61 Artwork by Jamie Oliver \u2794 61 The Influx by Craig Bowers \u2793 62 Artwork by Michael Norpell \u2794 63 editorial board 64 Editorial decision is shared equally among the Editorial Board. -64 Cover: Jamie Oliver -64 NOTE: With the exeption of Malfi Coast , all artwork listed as anonymous in the published table of contents appears to be signed by Ellen Gurley. 37th Yea
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