266 research outputs found

    Dammed water quality—Longitudinal stream responses below beaver ponds in the Umpqua River Basin, Oregon

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    Beaver-related restoration (BRR) has gained popularity as a means of improving stream ecosystems, but the effects are not fully understood. Studies of dissolved oxygen (DO) and water temperature, key water quality metrics for salmonids, have demonstrated improved conditions in some cases, but warming and decreased DO have been more commonly reported in meta-analyses. These results point to the contingencies that can influence outcomes from BRR. We examined water quality related to beaver ponds in a diverse coastal watershed (Umpqua River Basin, OR, USA). We monitored water temperature 0–400m above and below beaver ponds and at pond surfaces and bottoms across seven study sites from June through September of 2019. DO was also recorded at two sites at pond surfaces and pond bottoms. Downstream monthly mean daily maximum temperatures were warmer than upstream reference locations by up to 1.9°C at beaver dam outlets but this heating signal attenuated with downstream distance. Downstream warming was greatest in June and July and best predicted by pond bottom temperatures. DO at pond surfaces and bottoms were hypoxic (≤5 mg/L) for more than half of the 32-day monitoring period. Water temperatures increased for short distances below monitored beaver ponds and observed oxygen conditions within ponds were largely unsuitable for salmonid fishes. These findings contrast with some commonly stated expectations of BRR, and we recommend that managers consider these expectations prior to implementation. In some cases, project goals may override water quality concerns but in streams where temperature or DO restoration are objectives, managers may consider using BRR techniques with caution

    The Bolocam Galactic Plane Survey IX: Data Release 2 and Outer Galaxy Extension

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    We present a re-reduction and expansion of the Bolocam Galactic Plane Survey, first presented by Aguirre et al. (2011) and Rosolowsky et al. (2010). The BGPS is a 1.1 mm survey of dust emission in the Northern galactic plane, covering longitudes -10 < \ell < 90 and latitudes |b| < 0.5 with a typical 1-\sigma RMS sensitivity of 30-100 mJy in a 33" beam. Version 2 of the survey includes an additional 20 square degrees of coverage in the 3rd and 4th quadrants and 2 square degrees in the 1st quadrant. The new data release has improved angular recovery, with complete recovery out to 80" and partial recovery to 300", and reduced negative bowls around bright sources resulting from the atmospheric subtraction process. We resolve the factor of 1.5 flux calibration offset between the v1.0 data release and other data sets and determine that there is no offset between v2.0 and other data sets. The v2.0 pointing accuracy is tested against other surveys and demonstrated to be accurate and an improvement over v1.0. We present simulations and tests of the pipeline and its properties, including measurements of the pipeline's angular transfer function. The Bolocat cataloging tool was used to extract a new catalog, which includes 8594 sources, with 591 in the expanded regions. We have demonstrated that the Bolocat 40" and 80" apertures are accurate even in the presence of strong extended background emission. The number of sources is lower than in v1.0, but the amount of flux and area included in identified sources is larger.Comment: 36 pages, 16 figures, accepted to ApJS. Data available from http://irsa.ipac.caltech.edu/data/BOLOCAM_GPS

    The Bolocam Galactic Plane Survey. XIV. Physical Properties of Massive Starless and Star Forming Clumps

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    We sort 46834683 molecular clouds between 10<<6510^\circ< \ell <65^\circ from the Bolocam Galactic Plane Survey based on observational diagnostics of star formation activity: compact 7070 μm\mu{\rm m} sources, mid-IR color-selected YSOs, H2O{\rm H_2O} and CH3OH{\rm CH_3OH} masers, and UCHII regions. We also present a combined NH3{\rm NH_3}-derived gas kinetic temperature and H2O{\rm H_2O} maser catalog for 17881788 clumps from our own GBT 100m observations and from the literature. We identify a subsample of 22232223 (47.5%47.5\%) starless clump candidates, the largest and most robust sample identified from a blind survey to date. Distributions of flux density, flux concentration, solid angle, kinetic temperature, column density, radius, and mass show strong (>1>1 dex) progressions when sorted by star formation indicator. The median starless clump candidate is marginally sub-virial (α0.7\alpha \sim 0.7) with >75%>75\% of clumps with known distance being gravitationally bound (α<2\alpha < 2). These samples show a statistically significant increase in the median clump mass of ΔM170370\Delta M \sim 170-370 M_\odot from the starless candidates to clumps associated with protostars. This trend could be due to (i) mass growth of the clumps at M˙200440\dot{M}\sim200-440 Msun Myr1^{-1} for an average free-fall 0.80.8 Myr time-scale, (ii) a systematic factor of two increase in dust opacity from starless to protostellar phases, (iii) and/or a variation in the ratio of starless to protostellar clump lifetime that scales as M0.4\sim M^{-0.4}. By comparing to the observed number of CH3OH{\rm CH_3OH} maser containing clumps we estimate the phase-lifetime of massive (M>103M>10^3 M_\odot) starless clumps to be 0.37±0.08 Myr (M/103 M)10.37 \pm 0.08 \ {\rm Myr} \ (M/10^3 \ {\rm M}_\odot)^{-1}; the majority (M<450M<450 M_\odot) have phase-lifetimes longer than their average free-fall time.Comment: Accepted for publication in ApJ; 33 pages; 22 figures; 7 table

    TEG® and RapidTEG® are unreliable for detecting warfarin-coagulopathy: a prospective cohort study

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    BACKGROUND: Thromboelastography® (TEG) utilizes kaolin, an intrinsic pathway activator, to assess clotting function. Recent published studies suggest that TEG results are commonly normal in patients receiving warfarin, despite an increased International Normalized Ratio (INR). Because RapidTEG™ includes tissue factor, an extrinsic pathway activator, as well as kaolin, we hypothesized that RapidTEG would be more sensitive in detecting a warfarin-effect. METHODS: Included in this prospective study were 22 consecutive patients undergoing elective cardioversion and receiving warfarin. Prior to cardioversion, blood was collected to assess INR, Prothrombin Time, TEG, and RapidTEG. RESULTS: INR Results: 2.8 ± 0.5 (1.6 to 4.2). Prothrombin Time Results: 19.1 ± 2.2 (13.9. to 24.3). TEG Results (Reference Range): R-Time: 8.3 ± 2.7 (2–8); K-Time: 2.1 ± 1.4 (1–3); Angle: 62.5 ± 10.3 (55–78); MA: 63.2 ± 10.3 (51–69); G: 9.4 ± 3.5 (4.6-10.9); R-Time within normal range: 10 (45.5%) with INR 2.9 ± 0.3; Correlation coefficients for INR and each of the 5 TEG variables were insignificant (P > 0.05). RapidTEG Results (Reference Range): ACT: 132 ± 58 (86–118); K-Time: 1.2 ± 0.5 (1–2); Angle: 75.4 ± 5.2 (64–80); MA: 63.4 ± 5.1 (52–71); G: 8.9 ± 2.0 (5.0-11.6); ACT within normal range: 9 (40.9%) with INR 2.7 ± 0.5; Correlation coefficients for INR and each of the 5 RapidTEG variables were insignificant (P > 0.05). CONCLUSIONS: TEG, using kaolin activation, and RapidTEG, with kaolin and tissue factor activation, were normal in a substantial percent of warfarin patients, despite an increased INR. The false-negative rate for detecting warfarin coagulopathy with either test is unacceptable. The lack of correlation between INR and all TEG and RapidTEG components further indicates that these methodologies are insensitive to warfarin effects. Findings suggest that intrinsic pathway activation may mitigate detection of an extrinsic pathway coagulopathy

    A Study of Direct Author Subvention for Publishing Humanities Books at Two Universities: A Report to the Andrew W. Mellon Foundation by Indiana University and University of Michigan

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    This report was produced as the main deliverable from the Andrew W. Mellon Foundation Grant 41400692, “A Study of Direct Author Subvention for Publishing Humanities Books at Two Universities.” The Indiana University team led by PI Carolyn Walters, consisted of Jason Baird Jackson, Scott Smart, Nick Fitzgerald, Gary Dunham and Shayna Pekala. The University of Michigan team led by PI James Hilton consisted of Paul Courant, Sidonie Smith, Meredith Kahn, Charles Watkinson, Jim Ottaviani, and Aaron McCollough. Lead authorship of the different sections in this report is indicated in the opening paragraphs. Supplemental data to this report is available at http://hdl.handle.net/2022/20358.This white paper presents recommendations about how a system of monographic publication fully funded by subventions from authors’ parent institutions might function, based on research activities supported by the Andrew W. Mellon Foundation at Indiana University and the University of Michigan. While the contributors present a strong argument for implementing such an “author subvention” system, they describe a number of challenges and potential unintended consequences. Particular issues discussed include how to determine which publishers would be eligible for support, how best to support untenured faculty, and how to avoid disenfranchising scholars at less well-funded institutions.Andrew W. Mellon Foundatio

    The Luminosities of Protostars in the Spitzer c2d and Gould Belt Legacy Clouds

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    Motivated by the long-standing "luminosity problem" in low-mass star formation whereby protostars are underluminous compared to theoretical expectations, we identify 230 protostars in 18 molecular clouds observed by two Spitzer Space Telescope Legacy surveys of nearby star-forming regions. We compile complete spectral energy distributions, calculate Lbol for each source, and study the protostellar luminosity distribution. This distribution extends over three orders of magnitude, from 0.01 Lsun - 69 Lsun, and has a mean and median of 4.3 Lsun and 1.3 Lsun, respectively. The distributions are very similar for Class 0 and Class I sources except for an excess of low luminosity (Lbol < 0.5 Lsun) Class I sources compared to Class 0. 100 out of the 230 protostars (43%) lack any available data in the far-infrared and submillimeter (70 um < wavelength < 850 um) and have Lbol underestimated by factors of 2.5 on average, and up to factors of 8-10 in extreme cases. Correcting these underestimates for each source individually once additional data becomes available will likely increase both the mean and median of the sample by 35% - 40%. We discuss and compare our results to several recent theoretical studies of protostellar luminosities and show that our new results do not invalidate the conclusions of any of these studies. As these studies demonstrate that there is more than one plausible accretion scenario that can match observations, future attention is clearly needed. The better statistics provided by our increased dataset should aid such future work.Comment: Accepted for publication in AJ. 21 pages, 10 figures, 4 table

    Young Stellar Objects in the Gould Belt

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    We present the full catalog of Young Stellar Objects (YSOs) identified in the 18 molecular clouds surveyed by the Spitzer Space Telescope "cores to disks" (c2d) and "Gould Belt" (GB) Legacy surveys. Using standard techniques developed by the c2d project, we identify 3239 candidate YSOs in the 18 clouds, 2966 of which survive visual inspection and form our final catalog of YSOs in the Gould Belt. We compile extinction corrected SEDs for all 2966 YSOs and calculate and tabulate the infrared spectral index, bolometric luminosity, and bolometric temperature for each object. We find that 326 (11%), 210 (7%), 1248 (42%), and 1182 (40%) are classified as Class 0+I, Flat-spectrum, Class II, and Class III, respectively, and show that the Class III sample suffers from an overall contamination rate by background AGB stars between 25% and 90%. Adopting standard assumptions, we derive durations of 0.40-0.78 Myr for Class 0+I YSOs and 0.26-0.50 Myr for Flat-spectrum YSOs, where the ranges encompass uncertainties in the adopted assumptions. Including information from (sub)millimeter wavelengths, one-third of the Class 0+I sample is classified as Class 0, leading to durations of 0.13-0.26 Myr (Class 0) and 0.27-0.52 Myr (Class I). We revisit infrared color-color diagrams used in the literature to classify YSOs and propose minor revisions to classification boundaries in these diagrams. Finally, we show that the bolometric temperature is a poor discriminator between Class II and Class III YSOs.Comment: Accepted for publication in ApJS. 29 pages, 11 figures, 14 tables, 4 appendices. Full versions of data tables (to be published in machine-readable format by ApJS) available at the end of the latex source cod
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