Theory of structure and reactivity of carbon at transition metal surfaces

Imperial Users onl

Items on the Left Are Better Remembered

We report evidence of a new phenomenon from three experiments: a leftward bias when people try to remember visually presented information. Experiments 1 and 2 showed lateral leftward biases in memory in a large (total N>60000) sample of participants, with data collected via the British Broadcasting Corporation (BBC) web site. Experiment 3 replicated the findings of a leftwards bias in short-term memory with a more intensive data collection

Military reliability: is the gain worth the cost?

Thesis (M.BA.)--Boston Universit

Metamorphic Conditions of Adirondack Rocks

The Adirondack Highlands were metamorphosed to granulite facies conditions during the Ottawan phase (1090 to 1020 Ma) of the Grenville Orogenic Cycle, whereas the Adirondack Lowlands were metamorphosed to mid to upper amphibolite facies conditions during the Shawinigan phase (1190 to 1140) of the Grenville Orogenic Cycle. Metamorphic temperatures ranged from 750 °C to 850 °C in the Highlands and 650 °C to 750 °C in the Lowlands. Metamorphic pressures were between 6.0 and 8.6 kilobars in the Highlands and 6.5 to 7.5 kilobars in the Lowlands. Following the peak of metamorphism, Adirondack rocks took a counter-clockwise path in pressure-temperature space. The activity of water is generally low in Adirondack metamorphic rocks, and many rocks did not contain a free fluid phase during metamorphism

Mary Clifford Webster Darling Correspondence

Entries include some correct biographical information typed by the Maine State Library and handwritten correspondence on a Fredericka Manor card and plain paper stationery

Transport Property Requirements for Flow Battery Separators

Flow batteries are a promising technology for storing and discharging megawatt hours of electrical energy on the time scale of hours. The separator between the positive and negative electrodes strongly affects technical and economic performance. However, requirements for separators have not been reported in a general manner that enables quantitative evaluation of new systems such as nonaqueous flow batteries. This gap is addressed by deriving specifications for transport properties that are chemistry agnostic and align with aggressive capital cost targets. Three key transport characteristics are identified: area-specific resistance RΩ, crossover current density ix, and the coupling between crossover and capacity loss Ψ. Suggested maximum area-specific resistances are 0.29 and 2.3 Ω·cm[superscript 2] for aqueous and nonaqueous batteries, respectively. Allowable crossover rates are derived by considering the possible fates of active molecules that cross the separator and the coupling between Coulombic efficiency (CE) and capacity decline. The CE must exceed 99.992% when active species are unstable at the opposing electrode, while a CE of 97% can be tolerated when active molecules can be recovered from the opposing electrode. The contributions of diffusion, migration, and convection are discussed, quantified, and related to the physical properties of the separator and the active materials.United States. Department of Energy. Office of Basic Energy Sciences (Joint Center for Energy Storage Research

Are Protein Domains Modules of Lateral Genetic Transfer?

Background: In prokaryotes and some eukaryotes, genetic material can be transferred laterally among unrelated lineages and recombined into new host genomes, providing metabolic and physiological novelty. Although the process is usually framed in terms of gene sharing (e. g. lateral gene transfer, LGT), there is little reason to imagine that the units of transfer and recombination correspond to entire, intact genes. Proteins often consist of one or more spatially compact structural regions (domains) which may fold autonomously and which, singly or in combination, confer the protein's specific functions. As LGT is frequent in strongly selective environments and natural selection is based on function, we hypothesized that domains might also serve as modules of genetic transfer, i.e. that regions of DNA that are transferred and recombined between lineages might encode intact structural domains of proteins

Rearrangements in thyroid hormone receptor charge clusters that stabilize bound 3,5',5-triiodo-l-thyronine and inhibit homodimer formation

In this study, we investigated how thyroid hormone (3,5′,5-triiodo-l-thyronine, T3) inhibits binding of thyroid hormone receptor (TR) homodimers, but not TR-retinoid X receptor heterodimers, to thyroid hormone response elements. Specifically we asked why a small subset of TRβ mutations that arise in resistance to thyroid hormone syndrome inhibit both T3 binding and formation of TRβ homodimers on thyroid hormone response elements. We reasoned that these mutations may affect structural elements involved in the coupling of T3 binding to inhibition of TR DNA binding activity. Analysis of TR x-ray structures revealed that each of these resistance to thyroid hormone syndrome mutations affects a cluster of charged amino acids with potential for ionic bond formation between oppositely charged partners. Two clusters (1 and 2) are adjacent to the dimer surface at the junction of helices 10 and 11. Targeted mutagenesis of residues in Cluster 1 (Arg338, Lys342, Asp351, and Asp355) and Cluster 2 (Arg429, Arg383, and Glu311) confirmed that the clusters are required for stable T3 binding and for optimal TR homodimer formation on DNA but also revealed that different arrangements of charged residues are needed for these effects. We propose that the charge clusters are homodimer-specific extensions of the dimer surface and further that T3 binding promotes specific rearrangements of these surfaces that simultaneously block homodimer formation on DNA and stabilize the bound hormone. Our data yield insight into the way that T3 regulates TR DNA binding activity and also highlight hitherto unsuspected T3-dependent conformational changes in the receptor ligand binding domain