372 research outputs found

    Hidden intrabasin extension: Evidence for dike-fault interaction from magnetic, gravity, and seismic reflection data in Surprise Valley, northeastern California

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    The relative contributions of tectonic and magmatic processes to continental rifting are highly variable. Magnetic, gravity, and seismic reflection data from Surprise Valley, California, in the northwest Basin and Range, reveal an intrabasin, fault-controlled, ~10-m-thick dike at a depth of ~150 m, providing an excellent example of the interplay between faulting and dike intrusion. The dike, likely a composite structure representing multiple successive intrusions, is inferred from modeling a positive magnetic anomaly that extends ~35 km and parallels the basin-bounding Surprise Valley normal fault on the west side of the valley. A two-dimensional high-resolution seismic reflection profile acquired across the magnetic high images a normal fault dipping 56°E with ~275 m of throw buried ~60 m below the surface. Densely spaced gravity measurements reveal a \u3c1 mGal gravity low consistent with the fault offset inferred from the seismic data. Collinearity of the magnetic high and gravity low for ~6 km implies normal fault control of the dike along that length. The unusually shallow angle of the dike suggests that motion along the fault (perhaps aided by reduced friction along the dike) and associated block rotation resulted in post-intrusion tilting of the dike. The source of the dike is likely related to a shallow brittle-ductile transition zone that was elevated following rapid slip on the Surprise Valley fault after 3 Ma. Prior to our work, the Surprise Valley fault was assumed to accommodate the vast majority of extension across the region. Our results indicate that subsurface features, although no longer active, are significant contributors to the processes, timing, and total amount of extension observed in continental rift environments

    Increasing compliance with wearing a medical device in children with autism

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    Health professionals often recommend the use of medical devices to assess the health, monitor the well-being, or improve the quality of life of their patients. Children with autism may present challenges in these situations as their sensory peculiarities may increase refusals to wear such devices. To address this issue, we systematically replicated prior research by examining the effects of differential reinforcement of other behavior (DRO) to increase compliance with wearing a heart rate monitor in 2 children with autism. The intervention increased compliance to 100% for both participants when an edible reinforcer was delivered every 90 s. The results indicate that DRO does not require the implementation of extinction to increase compliance with wearing a medical device. More research is needed to examine whether the reinforcement schedule can be further thinned

    1942: Abilene Christian College Bible Lectures - Full Text

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    Delivered in the Auditorium of Abilene Christian College, February, 1942 Abilene, Texas Published September, 1942 Price: $1.00. FIRM FOUNDATION PUBLISHING HOUSE Austin, Texa

    Existence theorems for lagrange control problems with unbounded time domain

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    Existence theorems are proved for usual Lagrange control systems, in which the time domain is unbounded. As usual in Lagrange problems, the cost functional is an improper integral, the state equation is a system of ordinary differential equations, with assigned boundary conditions, and constraints may be imposed on the values of the state and control variables. It is shown that the boundary conditions at infinity require a particular analysis. Problems of this form can be found in econometrics (e.g., infinite-horizon economic models) and operations research (e.g., search problems).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45207/1/10957_2004_Article_BF00934054.pd

    'Throughout my life I've had people walk all over me': trauma in the lives of violent men

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    In this article we present original qualitative data gathered during prolonged ethnographic fieldwork with violent men in deindustrialised communities in the north of England. We use the data as an empirical platform for a theoretical exploration of the symbolism and subjectivising influences of traumatic life experiences in these men’s biographies. We conclude by making the tentative suggestion that there is a complex and mediated causal link between traumatic experience and a deep subjective commitment to aggression and violence in adulthood

    1954: Abilene Christian College Bible Lectures - Full Text

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    Preface The 1954 Abilene Christian College Lectureship was one of the best attended and most successful in the history of the school. Considerable interest was manifested in the timely theme, “Overcoming Dangerous Tendencies,” and in the two special topics, “Ways and Means of Doing Mission Work,” and “Caring For Widows and Orphans.” The reports from the mission fields were highly stimulating, and all in all, the speeches were unusually high caliber. The Panel Discussions were also on timely subjects and well presented. They received a warm response, as did also the thirty classes that were conducted each day. These classes were taught by persons expert in their particular fields, and covered a wide range of interests to the faithful, working Christian. We at Abilene Christian College predict for this book of Lectures a wide and hearty reception, and believe that its reading will issue in profit to the individual and to the church at large. J. D. Thomas Lectureship Directo

    Direct application of compound-specific radiocarbon analysis of leaf waxes to establish lacustrine sediment chronology

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    Author Posting. © Springer, 2007. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Journal of Paleolimnology 39 (2008): 43-60, doi:10.1007/s10933-007-9094-1.This study demonstrates use of compound-specific radiocarbon analysis (CSRA) for dating Holocene lacustrine sediments from carbonate-hosted Ordy Pond, Oahu, Hawaii. Long-chain odd-numbered normal alkanes (n-alkanes), biomarkers characteristic of terrestrial higher plants, were ubiquitous in Ordy Pond sediments. The δ13C of individual n-alkanes ranged from −29.9 to −25.5‰, within the expected range for n-alkanes synthesized by land plants using the C3 or C4 carbon fixation pathway. The 14C ages of n-alkanes determined by CSRA showed remarkably good agreement with 14C dates of rare plant macrofossils obtained from nearby sedimentary horizons. In general, CSRA of n-alkanes successfully refined the age-control of the sediments. The sum of n-alkanes in each sample produced 70–170 μg of carbon (C), however, greater age errors were confirmed for samples containing less than 80 μg of C. The 14C age of n-alkanes from one particular sedimentary horizon was 4,155 years older than the value expected from the refined age-control, resulting in an apparent and arguable age discrepancy. Several lines of evidence suggest that this particular sample was contaminated by introduction of 14C-free C during preparative capillary gas chromatography. This study simultaneously highlighted the promising potential of CSRA for paleo-applications and the risks of contamination associated with micro-scale 14C measurement of individual organic compounds.This project was funded by Petroleum Research Fund (PRF #40088-ACS) and in part by Sigma Xi, The Scientific Research Society (Grants in aid of research, 2003)

    Determinación de la madurez térmica de los carbones de la formación guaduas en el Sinclinal Checua - Lenguazaque

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    66 páginas : ilustraciones color, figuras, tablas.Se realizó un muestreo de los mantos de carbón en la formación Guaduas, flanco Occidental de la cuenca del sinclinal Checua-Lenguazaque, municipios de Sutatausa, Lenguazaque, Guachetá, Raquira y Samaca; con el fin de calcular el gradiente paleogeotérmico a partir del análisis reflectancia media de la vitrinita. El estudio determinó que los carbones de la zona tienen un rango de reflectancia media de 0.64 a 1.6, clasificándose como carbones desde bituminosos bajos volátiles hasta bituminosos altos volátiles. Para la determinación del gradiente paleogetermico se utilizó la fórmula propuesta por Baker, C & Pawlewicz, M, en la cual el valor de la reflectancia se tiene como variable principal; estableciéndose que para esta cuenta el gradiente geotérmico está en un rango de 520 C/Km hacia el sector de Sutatausa y de 1000C/Km hacia el sector de Samacá; asumiéndose que esta variación en el gradiente se debe al mayor efecto del fallamiento en la zona de Samacá que en Sutatausa.Bibliografía y webgrafía: páginas 64-65PregradoIngeniero Geólog

    Small-Bodied Humans from Palau, Micronesia

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    UNLABELLED: Newly discovered fossil assemblages of small bodied Homo sapiens from Palau, Micronesia possess characters thought to be taxonomically primitive for the genus Homo. BACKGROUND: Recent surface collection and test excavation in limestone caves in the rock islands of Palau, Micronesia, has produced a sizeable sample of human skeletal remains dating roughly between 940-2890 cal ybp. PRINCIPLE FINDINGS: Preliminary analysis indicates that this material is important for two reasons. First, individuals from the older time horizons are small in body size even relative to "pygmoid" populations from Southeast Asia and Indonesia, and thus may represent a marked case of human insular dwarfism. Second, while possessing a number of derived features that align them with Homo sapiens, the human remains from Palau also exhibit several skeletal traits that are considered to be primitive for the genus Homo. SIGNIFICANCE: These features may be previously unrecognized developmental correlates of small body size and, if so, they may have important implications for interpreting the taxonomic affinities of fossil specimens of Homo
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