David A. Budd

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Ocean acidification describes the progressive, global reduction in seawater pH that is currently underway because of the accelerating oceanic uptake of atmospheric CO(2). Acidification is expected to reduce coral reef calcification and increase reef dissolution. Inorganic cementation in reefs describes the precipitation of CaCO(3) that acts to bind(More)
BACKGROUND This study examined the psychometric relationship between the Word and Picture versions of the Free and Cued Selective Reminding Test (FCSRT) and developed an equation for score conversion. METHODS 187 participants were administered the FCSRT-Picture and FCSRT-Word on two visits using a randomized counterbalanced design. RESULTS Participants(More)
We describe an approach to estimating the crystallization temperatures of diagenetic calcites using clumped-isotope thermometry, a paleothermometer based on the C–O-bond enrichment in carbonates. Application of this thermometer to calcified gastropod shells and calcite cements in an early Eocene limestone from the Colorado Plateau reveals a record of(More)
Lateral metre-scale periodic variations in porosity and composition are found in many dolomite strata. Such variations may embed important information about dolomite formation and transformation. Here we show that these variations could be fossilized chemical waves emerging from stress-mediated mineral-water interaction during sediment burial diagenesis.(More)
Date The final copy of this thesis has been examined by the signatories, and we find that both the content and the form meet acceptable presentation standards of scholarly work in the above mentioned discipline. ABSTRACT This study identifies, characterizes, and analyzes the pore systems of the Niobrara Formation, and explores the linkage between measurable(More)
Introduction: Indurated surfaces on Mars, or martian duricrusts, are likely common surface types on Mars based on direct observations at spacecraft landing sites and remote-sensing data from orbit [1]. The crusted surfaces at the Viking lander sites were capable of supporting the spacecraft without significant deformation and showed discrete and coherent(More)
Studies at the intersection of cognitive science and linguistics have revealed the crucial role that metaphors play in shaping our thoughts about phenomena we cannot see. According to the domains interaction theory of cognition, a metaphoric expression sets up mappings between a target domain that we wish to understand and a familiar source domain. The(More)
Quartz is a common phase in high-silica igneous rocks and is resistant to post-eruptive alteration, thus offering a reliable record of magmatic processes in silicic magma systems. Here we employ the 75 ka Toba super-eruption as a case study to show that quartz can resolve late-stage temporal changes in magmatic δ18O values. Overall, Toba quartz crystals(More)
BACKGROUND Early screenings involving biomarkers and use of potential disease-modifying therapies (DMTs) may have significant humanistic implications for treatment strategies in Alzheimer's disease. METHODS Markov models simulated transitions of patient cohorts beginning in predementia, a hypothetical early stage of Alzheimer's disease marked by objective(More)
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