3,953 research outputs found

    Environment and Distribution of Age 0 Fishes in River Canard, a Lowland Ontario River

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    Age 0 fishes were collected to determine occurrence, relative abundance and species composition at three sites in River Canard, Ontario in spring-autumn, 1994-1995. This small lowland river (mean annual discharge, 3.2 m3 s-1) has variable flow during fish spawning and early nursery periods, high suspended particulate load, and sparse rooted vegetation and other physical cover. Forty-two taxa (12 families; 24,544 specimens) collected with beach seines and a plankton net represented a wide range of reproductive strategies and a diverse taxocene. Gizzard Shad Dorosoma cepedianum (67% of total catch), Orangespotted Sunfish Lepomis humilis (8%), and Brook Silverside Labidesthes sicculus (6%) were the most abundant species. Environmental conditions were such that fish attained autumnal lengths comparable to species in various systems throughout the ecoregion

    Description of Age-0 Round Goby, Neogobius melanostomus Pallas (Gobiidae), and Ecotone Utilisation in St. Clair Lowland Waters, Ontario

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    Early developmental stages and ecotone utilisation of the non-indigenous Round Goby, Neogobius melanostomus (Pallas, 1811), are described and illustrated. Fish (5-40 mm) were collected in coarse gravel, rocks and debris in the St. Clair River/Lake system, Ontario, in 1994-2000. The Round Goby hatches at about 5 mm with black eyes, flexed urostyle, and developed fins and digestive system. Distinguishing characters include large head, dorsolateral eyes, large fan-shaped pectoral fins, two dorsal fins, fused thoracic pelvic fins and a distinct black spot on the posterior of the spinous dorsal fin. Modal counts for preanal, postanal, and total myomeres were 12, 19, and 31, respectively

    Shooting the Messenger

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    Eleven experiments provide evidence that people have a tendency to ‘shoot the messenger,’ deeming innocent bearers of bad news unlikeable. In a pre-registered lab experiment, participants rated messengers who delivered bad news from a random drawing as relatively unlikeable (Study 1). A second set of studies points to the specificity of the effect: Study 2A shows that it is unique to the (innocent) messenger, and not mere bystanders. Study 2B shows that it is distinct from merely receiving information that one disagrees with. We suggest that people’s tendency to deem bearers of bad news as unlikeable stems in part from their desire to make sense of chance processes. Consistent with this account, receiving bad news activates the desire to sense-make (Study 3A), and in turn, activating this desire enhances the tendency to dislike bearers of bad news (Study 3B). Next, stemming from the idea that unexpected outcomes heighten the desire to sense-make, Study 4 shows that when bad news is unexpected, messenger dislike is pronounced. Finally, consistent with the notion that people fulfill the desire to sensemake by attributing agency to entities adjacent to chance events, messenger dislike is correlated with the belief that the messenger had malevolent motives (Studies 5A, 5B, & 5C). Studies 6A & 6B go further, manipulating messenger motives independently from news valence to suggest its causal role in our process account: the tendency to dislike bearers of bad news is mitigated when recipients are made aware of the benevolence of the messenger’s motives

    The Electronic and Superconducting Properties of Oxygen-Ordered MgB2 compounds of the form Mg2B3Ox

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    Possible candidates for the Mg2B3Ox nanostructures observed in bulk of polycrystalline MgB2 (Ref.1) have been studied using a combination of Z-contrast imaging, electron energy loss spectroscopy (EELS) and first-principles calculations. The electronic structures, phonon modes, and electron phonon coupling parameters are calculated for two oxygen-ordered MgB2 compounds of composition Mg2B3O and Mg2B3O2, and compared with those of MgB2. We find that the density of states for both Mg2B3Ox structures show very good agreement with EELS, indicating that they are excellent candidates to explain the observed coherent oxygen precipitates. Incorporation of oxygen reduces the transition temperature and gives calculated TC values of 18.3 K and 1.6 K for Mg2B3O and Mg2B3O2, respectively.Comment: Submitted to PR

    HIghMass - High HI Mass, HI-Rich Galaxies at z∼0z\sim0: Combined HI and H2_2 Observations

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    We present resolved HI and CO observations of three galaxies from the HIghMass sample, a sample of HI-massive (MHI>1010M⊙M_{HI} > 10^{10} M_\odot), gas-rich (MHIM_{HI} in top 5%5\% for their M∗M_*) galaxies identified in the ALFALFA survey. Despite their high gas fractions, these are not low surface brightness galaxies, and have typical specific star formation rates (SFR/M∗/M_*) for their stellar masses. The three galaxies have normal star formation rates for their HI masses, but unusually short star formation efficiency scale lengths, indicating that the star formation bottleneck in these galaxies is in the conversion of HI to H2_2, not in converting H2_2 to stars. In addition, their dark matter spin parameters (λ\lambda) are above average, but not exceptionally high, suggesting that their star formation has been suppressed over cosmic time but are now becoming active, in agreement with prior Hα\alpha observations.Comment: 20 pages, 13 figure

    Design, Construction, and Performance of Low-Level Radioactive Waste Disposal Facility

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    A mixed low-level radioactive waste (LLRW) and Resource Conservation and Recovery Act (RCRA) waste on-site disposal facility (OSDF) was constructed as part of the remediation of the U.S. Department of Energy Feed Material Production Center in Fernald, Ohio. The 56-acre OSDF is fully constructed, filled with waste, and closed. Post-closure monitoring is ongoing. This paper presents the design, construction, and performance of the OSDF. Waste acceptance criteria and waste placement requirements are described. Results from three sets of pre-design field and laboratory investigations are summarized. Currently available performance data for the OSDF’s leachate collection system and leakage detection system are reported. Post-closure monitoring activities are briefly described. The value of this case study is in providing a detailed framework for the conceptual and detailed design of land-based disposal facilities for mixed LLRW and RCRA waste
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