Tectonics, sedimentation, and hydrocarbon potential of the Reelfoot aulacogen

Thesis (M.S.)--University of Oklahoma, 1985.The Reelfoot aulacogen, an early Paleozoic failed-rift basin, lies concealed beneath the Gulf Coastal Plain strata of the upper Mississippi Embayment. Many similarities exist between the geologic history of the Reelfoot aulacogen and the coeval histories of the adjacent Paleozoic continental margins of North America. Plate tectonic theory provides useful concepts to explain the histories of both continental margins and intracratonic structural features. Widespread continental extension (continental break-up) occurred in the latest Precambrian-Early Cambrian and initiated rifting in intracratonic areas. Rifting proceeded in some areas to drifting with generation of oceanic crust and formation of the Paleozoic continental margins of North America. Other areas, such as the Reelfoot rift, ceased rifting and subsided passively to form broad downwarped troughs above rift graben systems. Post-rifting subsidence in the Reelfoot area resulted primarily from cooling of the anomalous lithosphere that formed beneath the rift during extension and corresponds to post-rifting, passive subsidence of the continental margins. Convergent plate interactions affect the interiors of continents as well as their margins, especially along lines of pre-existing weakness. Late Paleozoic plate convergences and continental collisions caused both compressive and extensional reactivation of certain ancient normal faults in the Reelfoot aulacogen that had formed initially during rifting. Post-Paleozoic faulting, generally related to reactivated basement normal faults, occurred in the Late Cretaceous, Tertiary, and Quaternary. Earthquakes in the Reelfoot aulacogen indicate continued faulting that results from the present-day stress field acting on certain ancient crustal weaknesses, usually reactivated rift stage faults. The hydrocarbon potential of the Reelfoot area is discussed in terms of source rocks, reservoirs, and traps. Potential hydrocarbon prospects include broad anticlines, horst block highs, forced and compaction folds over block edges, normal and reverse faulted anticlines, submarine fans, carbonate buildups and shoals, stratigraphic pinchouts, truncation traps, unconformities, fracture reservoir trends, and shelf-basin hingelines. Reflection seismic profiles show examples of prospect types

Characteristics of long-duration inhibitory postsynaptic potentials in rat neocortical neurons in vitro

1. The characteristics of long-duration inhibitory postsynaptic potentials (l-IPSPs) which are evoked in rat frontal neocortical neurons by local electrical stimulation were investigated with intracellular recordings from anin vitro slice preparation. 2. Stimulation with suprathreshold intensities evoked l-IPSPs with typical durations of 600–900 msec at resting membrane potential. Conductance increases of 15–60% were measured at the peak amplitude of l-IPSPs (150–250 msec poststimulus). 3. The duration of the conductance increases during l-IPSPs displayed a significant voltage dependence, decreasing as the membrance potential was depolarized and increasing with hyperpolarization. 4. The reversal potential of l-IPSPs is significantly altered by reductions in the extracellular potassium concentration. Therefore it is concluded that l-IPSPs in rat neocortical neurons are generated by the activation of a potassium conductance. 5. l-IPSPs exhibit stimulation fatigue. Stimulation with a frequency of 1 Hz produces a complete fatigue of the conductance increases during l-IPSPs after approximately 20 consecutive stimuli. Recovery from this fatigue requires minutes. 6. l-IPSPs are not blocked by bicuculline but are blocked by baclofen

Evolution of Chloroplast Transcript Processing in Plasmodium and Its Chromerid Algal Relatives

Chloroplasts contain their own genomes, containing two broad functional types of gene: genes encoding proteins directly involved in photosynthesis, and genes with a non-photosynthesis function, such as cofactor biosynthesis, assembly of protein complexes, or expression of the chloroplast genome. Thus far, to our knowledge, no chloroplast gene expression pathways in any lineage have been found to target one functional category of gene specifically. Here, we show that a chloroplast RNA processing pathway – the addition of a 3′ poly(U) tail – is specifically associated with photosynthesis genes in two species of algae, the ‘chromerids’ Chromera and Vitrella. The addition of the poly(U) tail enables the precise processing of mature photosynthesis gene transcripts from precursor RNA, and is likely to be essential for expression of the chromerid photosynthesis machinery. The chromerid algae are the closest photosynthetic relatives of a parasitic group of eukaryotes, the apicomplexans, which include the malaria pathogen Plasmodium. Apicomplexans are descended from algae, and retain a reduced chloroplast, which contains genes only of non-photosynthesis function. We have confirmed that 3′ poly(U) tails are not added to Plasmodium chloroplast transcripts. The expression pathways associated with photosynthesis genes have therefore been lost in the evolution of the apicomplexan chloroplast, and this loss could potentially have driven the transition from photosynthesis to parasitism

Social Competence Treatment after Traumatic Brain Injury: A Multicenter, Randomized, Controlled Trial of Interactive Group Treatment versus Non-Interactive Treatment

Objective To evaluate the effectiveness of a replicable group treatment program for improving social competence after traumatic brain injury (TBI). Design Multicenter randomized controlled trial comparing two methods of conducting a social competency skills program, an interactive group format versus a classroom lecture. Setting Community and Veteran rehabilitation centers. Participants 179 civilian, military, and veteran adults with TBI and social competence difficulties, at least 6 months post-injury. Experimental Intervention Thirteen weekly group interactive sessions (1.5 hours) with structured and facilitated group interactions to improve social competence. Alternative (Control) Intervention Thirteen traditional classroom sessions using the same curriculum with brief supplemental individual sessions but without structured group interaction. Primary Outcome Measure Profile of Pragmatic Impairment in Communication (PPIC), an objective behavioral rating of social communication impairments following TBI. Secondary Outcomes LaTrobe Communication Questionnaire (LCQ), Goal Attainment Scale (GAS), Satisfaction with Life Scale (SWLS), Post-Traumatic Stress Disorder Checklist – (PCL-C), Brief Symptom Inventory 18 (BSI-18), Scale of Perceived Social Self Efficacy (PSSE). Results Social competence goals (GAS) were achieved and maintained for most participants regardless of treatment method. Significant improvements in the primary outcome (PPIC) and two of the secondary outcomes (LCQ and BSI) were seen immediately post-treatment and at 3 months post-treatment in the AT arm only, however these improvements were not significantly different between the GIST and AT arms. Similar trends were observed for PSSE and PCL-C. Conclusions Social competence skills improved for persons with TBI in both treatment conditions. The group interactive format was not found to be a superior method of treatment delivery in this study

Book Reviews

Review of the following books: Revolutionary Outlaws: Ethan Allen and the Struggle for Independence on the Early American Frontier by Michael A. Bellesiles; The Salem Witch Crisis by Larry Gragg; Hard Times, Hard Men: Maine and the Irish, 1830-1860 by James H. Mundy; Keepers of Our Past: Local Historical Writing in the United States, 1820s-1930s by David J. Russo; Woodsmen and Whigs: Historic Images of Bangor, Maine by Abigail Ewing Zelz and Marily Zoidis; Bethel, Maine: An Illustrated History by Randall H. Bennett; Dearest Father: The Civil War Letters of Lt. Frank Dickerson, a Son of Belfast, Maine by H. Draper Hunt

Probing multiscale factors affecting the reactivity of nanoparticle-bound molecules

I. K. M., W. E., E. J. H, S. S. and E. R. K. are grateful for funding from the Leverhulme Trust [RPG-2015-042], the Engineering and Physical Sciences Research Council [EP/K016342/1], the University of St Andrews, and the EPSRC Centre for Doctoral Training in Critical Resource Catalysis (CRITICAT) [Ph.D. studentship to SS: EP/L016419/1]. D. M. and P.P thank the Italian Ministry of University Research (MIUR) for funding [RBSI14PBC6].The structures and physicochemical properties of surface-stabilizing molecules play a critical role in defining the properties, interactions, and functionality of hybrid nanomaterials such as monolayer-stabilized nanoparticles. Concurrently, the distinct surface-bound interfacial environment imposes very specific conditions on molecular reactivity and behavior in this setting. Our ability to probe hybrid nanoscale systems experimentally remains limited, yet understanding the consequences of surface confinement on molecular reactivity is crucial for enabling predictive nanoparticle synthon approaches for postsynthesis engineering of nanoparticle surface chemistry and construction of devices and materials from nanoparticle components. Here, we have undertaken an integrated experimental and computational study of the reaction kinetics for nanoparticle-bound hydrazones, which provide a prototypical platform for understanding chemical reactivity in a nanoconfined setting. Systematic variation of just one molecular-scale structural parameter—the distance between reactive site and nanoparticle surface—showed that the surface-bound reactivity is influenced by multiscale effects. Nanoparticle-bound reactions were tracked in situ using 19F NMR spectroscopy, allowing direct comparison to the reactions of analogous substrates in bulk solution. The surface-confined reactions proceed more slowly than their solution-phase counterparts, and kinetic inhibition becomes more significant for reactive sites positioned closer to the nanoparticle surface. Molecular dynamics simulations allowed us to identify distinct supramolecular architectures and unexpected dynamic features of the surface-bound molecules that underpin the experimentally observed trends in reactivity. This study allows us to draw general conclusions regarding interlinked structural and dynamical features across several length scales that influence interfacial reactivity in monolayer-confined environments.PostprintPeer reviewe

The anisotropic hard-sphere crystal-melt interfacial free energy from fluctuations

This is the publisher's version, also available electronically from http://scitation.aip.org/content/aip/journal/jcp/125/9/10.1063/1.2338303.We have calculated the interfacial free energy for the hard-sphere system, as a function of crystal interface orientation, using a method that examines the fluctuations in the height of the interface during molecular dynamics simulations. The approach is particularly sensitive for the anisotropy of the interfacial free energy. We find an average interfacial free energy of γ=0.56±0.02kBTσ−2. This value is lower than earlier results based upon direct calculations of the free energy [R. L. Davidchack and B. B. Laird, Phys. Rev. Lett.85, 4751 (2000)]. However, both the average value and the anisotropy agree with the recent values obtained by extrapolation from direct calculations for a series of the inverse-power potentials [R. L. Davidchack and B. B. Laird, Phys. Rev. Lett.94, 086102 (2005)]

Vacua of M-theory and string theory

We argue that supersymmetric higher-dimension operators in the effective actions of M-theory and IIB string theory do not affect the maximally supersymmetric vacua: $adS_4\times S^7$ and $adS_7\times S^4$ in M-theory and $adS_5\times S^5$ in IIB string theory. All these vacua are described in superspace by a fixed point with all components of supertorsion and supercurvature being supercovariantly constant. This follows from 32 unbroken supersymmetries and allows us to prove that such vacua are exact.Comment: 16 pages, late

A new way to rapidly create functional, fluorescent fusion proteins: random insertion of GFP with an in vitro transposition reaction

BACKGROUND: The jellyfish green fluorescent protein (GFP) can be inserted into the middle of another protein to produce a functional, fluorescent fusion protein. Finding permissive sites for insertion, however, can be difficult. Here we describe a transposon-based approach for rapidly creating libraries of GFP fusion proteins. RESULTS: We tested our approach on the glutamate receptor subunit, GluR1, and the G protein subunit, α(s). All of the in-frame GFP insertions produced a fluorescent protein, consistent with the idea that GFP will fold and form a fluorophore when inserted into virtually any domain of another protein. Some of the proteins retained their signaling function, and the random nature of the transposition process revealed permissive sites for insertion that would not have been predicted on the basis of structural or functional models of how that protein works. CONCLUSION: This technique should greatly speed the discovery of functional fusion proteins, genetically encodable sensors, and optimized fluorescence resonance energy transfer pairs

Isolation of YAC Clones From the Pericentromeric Region of Chromosome 10 and Development of New Genetic Markers Linked to the Multiple Endocrine Neoplasia Type 2A Gene

Genetic linkage mapping and contig assembly using yeast artificial chromosome (YAC) technology form the basis of our strategy to clone and define the genomic structure of the pericentromeric region of chromosome 10 containing the multiple endocrine neoplasia type 2A gene. Thus far YAC walks have been initiated from five chromosome 10 pericentromeric loci including RBP3, D10S94, RET, D10Z1, and FNRB. Long range pulsed-field gel electrophoresis maps are constructed from the YACs isolated to define clone overlaps and to identify putative CpG islands. Bidirectional YAC walks are continued by rescreening the YAC library with sequence-tagged site assays developed from endclones. Several new restriction fragment length polymorphisms and simple sequence repeat polymorphism markers have been identified from the YAC clones. In particular, two highly informative (CA)n dinucleotide repeat markers, sTCL-1 from proximal chromosome 10p (16 alleles, PIC = 0.68) and sJRH-1 from the RBP3 locus (18 alleles. PIC = 0.88), provide useful reagents for a polymerase chain reaction-based predictive genetic test that can be performed rapidly from small amounts of DNA