232 research outputs found

    Third-Party Effects in Stakeholder Interviews

    Get PDF
    This paper examines the effect of having a third-party scientific expert present in stakeholder interviews. The study was conducted as part of a larger project on stakeholder engagement for natural resource management in the Verde Valley region of Arizona. We employed an experimental design, conducting stakeholder interviews both with and without an identified scientific expert present. Our sample consisted of 12 pairs of interviewees (24 total participants) who we matched based on their occupation, sex, and spatial proximity. For each pair, the scientific expert was present as a third party in one interview and absent in the other. We used a word-based coding strategy to code all interview responses for three known areas of sensitivity among the study population (risk, gatekeeping, and competence). We then performed both quantitative and qualitative analyses to compare responses across the two interview groups. We found that the presence of a scientific expert did not have a statistically significant effect on the mention of sensitive topics among stakeholders. However, our qualitative results show that the presence of a scientific expert had subtle influences on the ways that stakeholders discussed sensitive topics, particularly in placing emphasis on their own credibility and knowledge. Our findings indicate that researchers may be able to pursue collaborative, interdisciplinary research designs with multiple researchers present during interviews without concerns of strongly influencing data elicitation on sensitive topics. However, researchers should be cognizant of the subtle ways in which the presence of a third-party expert may influence the credibility claims and knowledge assertions made by respondents when a third-party expert is present during stakeholder interviews

    Hybrid Bermudagrass Responses to Impaired Water Sources

    Get PDF
    Low-quality (i.e., impaired) water sources are commonly used to irrigate warm-season turfgrass landscapes as a result of limited supplies of potable water sources. Currently, there is great need to define the impacts of impaired water sources on turfgrass water consumption, growth, and quality. The objectives of this study were to characterize actual evaporation (ETa), clipping production, and quality of three hybrid bermudagrass varieties [‘TifTuf’, ‘Tifway’, and ‘Midiron’; Cynodon dactylon (L.) Pers. × C. traansvalensis Burtt Davy] grown under three water sources [reverse osmosis (RO), local well, and recycled], each supplied at full irrigation levels (1.0 × ETa) over two 8-week study periods. When pooling across water source and date, TifTuf maintained the highest visual quality and normalized difference vegetation index (NDVI) compared with both Midiron and Tifway. This was accompanied by a greater daily ETa rate, clipping production, and water use efficiency (WUE) compared with Midiron in both studies. When pooling across variety and date, daily ETa of turfgrass receiving recycled water was 5% to 10% less than those receiving the local well or RO water. In addition, turfgrasses receiving local well water held the greatest visual quality and NDVI compared with those receiving either RO water in the summer study. Visual quality and NDVI were also less in turfgrasses receiving RO water compared with those receiving local well or recycled water in the fall. Despite turfgrasses having a lower ETa under recycled water in both study periods, these plants had significantly greater clipping production compared with RO water in the summer. Also, clipping production under recycled water did not differ significantly from the other two sources in the fall study. Furthermoe, in both studies, WUE was similar for turfgrasses receiving recycled water compared with those receiving RO or local well water. Results demonstrated that irrigation water quality influences critical factors for hybrid bermudagrass growth and that considerable variability exists among three commercially available varieties for evapotranspiration rates, quality, and clipping production

    Fine sediment reduces vertical migrations of Gammarus pulex (Crustacea: Amphipoda) in response to surface water loss

    Get PDF
    Surface and subsurface sediments in river ecosystems are recognized as refuges that may promote invertebrate survival during disturbances such as floods and streambed drying. Refuge use is spatiotemporally variable, with environmental factors including substrate composition, in particular the proportion of fine sediment (FS), affecting the ability of organisms to move through interstitial spaces. We conducted a laboratory experiment to examine the effects of FS on the movement of Gammarus pulex Linnaeus (Crustacea: Amphipoda) into subsurface sediments in response to surface water loss. We hypothesized that increasing volumes of FS would impede and ultimately prevent individuals from migrating into the sediments. To test this hypothesis, the proportion of FS (1–2 mm diameter) present within an open gravel matrix (4–16 mm diameter) was varied from 10 to 20% by volume in 2.5% increments. Under control conditions (0% FS), 93% of individuals moved into subsurface sediments as the water level was reduced. The proportion of individuals moving into the subsurface decreased to 74% at 10% FS, and at 20% FS no individuals entered the sediments, supporting our hypothesis. These results demonstrate the importance of reducing FS inputs into river ecosystems and restoring FS-clogged riverbeds, to promote refuge use during increasingly common instream disturbances

    Search for Θ+(1540)\Theta^+(1540) pentaquark in high statistics measurement of γpKˉ0K+n\gamma p \to \bar K^0 K^+ n at CLAS

    Full text link
    The exclusive reaction γpKˉ0K+n\gamma p \to \bar K^0 K^+ n was studied in the photon energy range between 1.6-3.8 GeV searching for evidence of the exotic baryon Θ+(1540)nK+\Theta^+(1540)\to nK^+. The decay to nK+nK^+ requires the assignment of strangeness S=+1S=+1 to any observed resonance. Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility corresponding to an integrated luminosity of 70 pb1pb^{-1}. No evidence for the Θ+\Theta^+ pentaquark was found. Upper limits were set on the production cross section as function of center-of-mass angle and nK+nK^+ mass. The 95% CL upper limit on the total cross section for a narrow resonance at 1540 MeV was found to be 0.8 nb.Comment: Submitted to Physical Review Letter

    Tracking replication enzymology in vivo by genome-wide mapping of ribonucleotide incorporation

    Get PDF
    Ribonucleotides are frequently incorporated into DNA during eukaryotic replication. Here we map the genome-wide distribution of these ribonucleotides as markers of replication enzymology in budding yeast, using a new 5′-DNA end-mapping method, Hydrolytic End Sequencing. HydEn-Seq of DNA from ribonucleotide excision repair-deficient strains reveals replicase- and strand-specific patterns of ribonucleotides in the nuclear genome. These patterns support the role of DNA polymerases α and δ in lagging strand replication and of DNA polymerase ε in leading strand replication. They identify replication origins, termination zones and variations in ribonucleotide incorporation frequency across the genome that exceed three orders of magnitude. HydEn-Seq also reveals strand-specific 5′-DNA ends at mitochondrial replication origins, suggesting unidirectional replication of a circular genome. Given the conservation of enzymes that incorporate and process ribonucleotides in DNA, HydEn-Seq can be used to track replication enzymology in other organisms

    First measurement of direct f0(980)f_0(980) photoproduction on the proton

    Get PDF
    We report on the results of the first measurement of exclusive f0(980)f_0(980) meson photoproduction on protons for Eγ=3.03.8E_\gamma=3.0 - 3.8 GeV and t=0.41.0-t = 0.4-1.0 GeV2^2. Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility. The resonance was detected via its decay in the π+π\pi^+ \pi^- channel by performing a partial wave analysis of the reaction γppπ+π\gamma p \to p \pi^+ \pi^-. Clear evidence of the f0(980)f_0(980) meson was found in the interference between PP and SS waves at Mπ+π1M_{\pi^+ \pi^-}\sim 1 GeV. The SS-wave differential cross section integrated in the mass range of the f0(980)f_0(980) was found to be a factor of 50 smaller than the cross section for the ρ\rho meson. This is the first time the f0(980)f_0(980) meson has been measured in a photoproduction experiment

    Species-Specific Means and Within-Species Variance in Glucocorticoid Hormones and Speciation Rates in Birds

    Get PDF
    At macroevolutionary scales, stress physiology may have consequences for species diversification and subspecies richness. Populations that exploit new resources or undergo range expansion should cope with new environmental challenges, which could favor higher mean stress responses. Within-species variation in the stress response may also play a role in mediating the speciation process: in species with broad variation, there will always be some individuals that can tolerate an unpredictable environment, whereas in species with narrow variation there will be fewer individuals that are able to thrive in a new ecological niche. We tested for the evolutionary relationship between stress response, speciation rate, and subspecies richness in birds by relying on the HormoneBase repository, from which we calculated within- and among-species variation in baseline (BL) and stress-induced (SI) corticosterone levels. To estimate speciation rates, we applied Bayesian analysis of macroevolutionary mixtures that can account for variation in diversification rate among clades and through time. Contrary to our predictions, lineages with higher diversification rates were not characterized by higher BL or SI levels of corticosterone either at the tips or at the deeper nodes of the phylogeny. We also found no association between mean hormone levels and subspecies richness. Within-species variance in corticosterone levels showed close to zero repeatability, thus it is highly unlikely that this is a species-specific trait that influences diversification rates. These results imply that stress physiology may play a minor, if any, role in determining speciation rates in birds

    Altered microRNA expression in frontotemporal lobar degeneration with TDP-43 pathology caused by progranulin mutations

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Frontotemporal lobar degeneration (FTLD) is a progressive neurodegenerative disorder that can be triggered through genetic or sporadic mechanisms. MicroRNAs (miRNAs) have become a major therapeutic focus as their pervasive expression and powerful regulatory roles in disease pathogenesis become increasingly apparent. Here we examine the role of miRNAs in FTLD patients with TAR DNA-binding protein 43 pathology (FTLD-TDP) caused by genetic mutations in the progranulin (<it>PGRN</it>) gene.</p> <p>Results</p> <p>Using miRNA array profiling, we identified the 20 miRNAs that showed greatest evidence (unadjusted P < 0.05) of dysregulation in frontal cortex of eight FTLD-TDP patients carrying <it>PGRN </it>mutations when compared to 32 FTLD-TDP patients with no apparent genetic abnormalities. Quantitative real-time PCR (qRT-PCR) analyses provided technical validation of the differential expression for 9 of the 20 miRNAs in frontal cortex. Additional qRT-PCR analyses showed that 5 out of 9 miRNAs (miR-922, miR-516a-3p, miR-571, miR-548b-5p, and miR-548c-5p) were also significantly dysregulated (unadjusted P < 0.05) in cerebellar tissue samples of <it>PGRN </it>mutation carriers, consistent with a systemic reduction in PGRN levels. We developed a list of gene targets for the 5 candidate miRNAs and found 18 genes dysregulated in a reported FTLD mRNA study to exhibit anti-correlated miRNA-mRNA patterns in affected cortex and cerebellar tissue. Among the targets is brain-specific angiogenesis inhibitor 3, which was recently identified as an important player in synapse biology.</p> <p>Conclusions</p> <p>Our study suggests that miRNAs may contribute to the pathogenesis of FTLD-TDP caused by <it>PGRN </it>mutations and provides new insight into potential future therapeutic options.</p

    Mode of Effective Connectivity within a Putative Neural Network Differentiates Moral Cognitions Related to Care and Justice Ethics

    Get PDF
    BACKGROUND: Moral sensitivity refers to the interpretive awareness of moral conflict and can be justice or care oriented. Justice ethics is associated primarily with human rights and the application of moral rules, whereas care ethics is related to human needs and a situational approach involving social emotions. Among the core brain regions involved in moral issue processing are: medial prefrontal cortex, anterior (ACC) and posterior (PCC) cingulate cortex, posterior superior temporal sulcus (pSTS), insula and amygdala. This study sought to inform the long standing debate of whether care and justice moral ethics represent one or two different forms of cognition. METHODOLOGY/PRINCIPAL FINDINGS: Model-free and model-based connectivity analysis were used to identify functional neural networks underlying care and justice ethics for a moral sensitivity task. In addition to modest differences in patterns of associated neural activity, distinct modes of functional and effective connectivity were observed for moral sensitivity for care and justice issues that were modulated by individual variation in moral ability. CONCLUSIONS/SIGNIFICANCE: These results support a neurobiological differentiation between care and justice ethics and suggest that human moral behavior reflects the outcome of integrating opposing rule-based, self-other perspectives, and emotional responses
    corecore