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Hydrocarbon reservoirs in the Mississippian system of south central Kansas are difficult to understand due to subtle rock properties (i.e., arbitrary porosities, complex trends of neomorphism, intricate fracture, and cementation patterns, etc.) that resulted mostly from different diagenetic processes. Inasmuch as the porosity and the permeability of a reservoir result from passage through different diagenetic environments, any reservoir quality evaluation needs a deliberate knowledge of diagenesis in the formation to maximize their production capacity. The objective of this research is to determine the origin and nature of the different diagenetic facies in the Mississippian system and understand their stratigraphic distribution in south central Kansas. Five cores are being described to determine the different depositional facies and diagenetic facies. Transmitted light microscopy, cathodoluminescence, and scanning electron microscopy will be used for thin-section descriptions of each core. Petrographic descriptions will be accompanied by geochemical analysis (stable isotopes, Fe and Mn concentrations, TOC concentrations, and x-ray diffraction) to determine the diagenetic environment at which minerals are precipitated and the source of the diagenetic fluids that altered the rock.
Ballroom C - 155 FRANCEVILLITE [(BA,PB)(UO2)2(V2O8)•5H2O] IDENTIFIED IN THE URANIUM VANADIUM DEPOSITS IN THE
PRYOR MOUNTAIN MINING DISTRICT, MONTANA, AND THE LITTLE MOUNTAIN MINING DISTRICT, WYOMING,
MAY PROVIDE A LINK TO THE ELEVATED LEAD IN THE BIGHORN RIVERAnita Moore-Nall, David Lageson.
Montana State University, Bozeman, Bozeman, MT.
The Bighorn River is a declared 303d-impaired waterway once it passes through the Pryor Mountains on the Crow Reservation. The 303d designation is due to elevated lead and mercury. Uranium vanadium deposits in the Pryor Mountains of Montana and the Little Mountain Mining District of Northern Wyoming are characterized by collapse breccia features in a paleokarst horizon of the Madison Limestone. Both districts are located in Laramide structures.
The Little Sheep Mountain anticline, a similar structure located near Lovell, Wyoming, hosts a cave with uraniumbearing hydrothermal fluids. This structure is superimposed by the Bighorn River and may provide a modern-day analogue to the depositional mode of mineralization for these 2 districts. Rock samples were collected from several mines, and water and mud samples were collected from Lower Kane Cave for analytical work. Francevillite [(Ba,Pb) (UO2)2(V2O8)•5H2O] was identified using X-ray diffraction analysis (XRD) and scanning electron microscope (SEM) spot elemental analysis with energy dispersive X-ray spectrometry (EDS). The mineral was found with and closely resembles metatyuyamunite [Ca (UO2)2V5+2O8•3(H2O)], the primary ore of the two districts. Variations of barite, disseminated sulfides, purple fluorite, green radioactive calcite, and quartz, sometimes of the Herkimer style, are common in the mineralized portions of the two districts. Lead was detected in mud and water samples from Lower Kane Cave and analyzed at Energy Laboratories in Billings, Montana. This study may show that structurally controlled migration of warm, metal enriched fluids may be the mode of mineralization for the 2 districts and the source of lead in the Bighorn River.
322 GRADUATE POSTER ABSTRACTS
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THE 1.4 EVERGREEN VALLEY GRANITE-GABBRO COMPLEX - IMPLICATIONS FOR TECTONIC-MAGMATIC
SETTING IN THE MIDDLE PROTEROZOICAndrew Romero, Jennifer Lindline.
New Mexico Highlands University, Las Vegas, NM.
The Mesoproterozoic Evergreen Valley Plutonic Complex (EVPC) exposed in the southern Sangre de Cristo Mountains of New Mexico is a bimodal granite-gabbro intrusion that shows field evidence for hybridization. Bimodal magmatism has typically characterized intraplate magmatic settings, though bimodal magmatism in intraoceanic arc settings is not atypical. Studies of the 1.4 Ga Sandia pluton, the 1.4 Ga Priest pluton, and others demonstrate that the
1.4 granites were emplaced under a regional NW-SE compressive regime, which support granite emplacement during a terrane collision event. Reconnaissance field study of the EVPC, however, reveals that these rocks are non-foliated and undeformed, conflicting with studies arguing for a 1.4 Ga orogenic event. The purpose of this study is to assess the mechanism of pluton emplacement as well as to determine the igneous processes (magma mingling, magma mixing, fractional crystallization, and assimilation) that affected its final composition. Field and microscopic structural relationships will assess the setting of pluton emplacement (syntectonic versus post-tectonic). Petrological and geochemical analysis will aid in the determination of the crystallization history and petrogenic relationships between the various rock types within the complex. This study will situate the emplacement of the complex into the appropriate tectonic regime at 1.4 Ga.
PHYSICS (EXCEPT BIOPHYSICS)
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FABRICATION AND ANALYSIS OF HIGHLY EPITAXIAL PRBACO2O5.5+ Δ THIN FILMSErik Enriquez, Xing Xu, Shanyong Bao, Chonglin Chen.
University of Texas at San Antonio, San Antonio, TX.
Double perovskite cobaltate PrBaCo2O5.5+δ thin films are grown on various substrates by pulsed laser deposition technique. The films are layered perovskites with alternating Co-O square pyramid and octahedral layers along c-axis.
Depending on the oxygen content, there are various cobalt valences (Co2+ / Co3+ / Co4+), resulting in a variation of the structure as well as the magnetic and electrical transport properties. Microstructural characterizations from X-ray diffraction and electron microscopy indicate that the as-grown films have good single crystalline quality and epitaxial behavior. The response of the films to changes in temperature and ambient environment are systematically studied.
The effects of several dopants to the A-site or A- and B-site cations (Ca doping, or Sr and Fe doping, respectively) on the resulting physical properties of the films will be presented.
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MAGNETIC PROPERTIES AND PHASE TRANSITIONS OF GADOLINIUM-INFUSED CARBON NANOTUBESAbdiel Quetz1, Igor Doubenko1, Tapas Samanta1, Herbert Vinson1, Saikat Talapatra1, Naushad Ali1, Shane Stadler2.
Southern Illinois University at Carbondale, Carbondale, IL, 2Louisiana State University, Baton Rouge, LA.
A ferromagnetic-type transition at TC ∼ 320 K, accompanied by jump-like change in magnetization and temperature respectively. The Gd clusters have a non-uniform distribution and are mostly concentrated at the ends of the CNTs.
hysteresis typical for the temperature-induced first order phase transitions has been observed by magnetization measurements. It was found that Gd infused into the CNTs by annealing results in a first order paramagneticferromagnetic transition at TC = 320 K. Complementary research is been performed with shorter carbon nanotubes.
323 GRADUATE POSTER ABSTRACTS
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OFF-AXIS ELECTRON HOLOGRAPHY USED TO EXTRACT STRUCTURAL PROPERTIES IN
NANOSTRUCTURED MATERIALSJesus Cantu, Arturo Ponce-Pedraza, Francisco Ruiz, Miguel Jose Yacaman.
University of Texas at San Antonio, San Antonio, TX.
An electron hologram is a fringe-modulated image containing the complete information, amplitude, and phase of an electron transparent object. Electron holography is an interferometric technique that has recently been a very reliable technique to extract quantitative information such as electro and magneto static fields, impurities in solids, determination of the thickness, and the lattice distortion in nanostructured materials. Since electrons have a high spatial coherence, electron holography has a significant potential in the determination of physical properties at high spatial resolution and sensitivity. The holograms are collected by the interference between one reference and one object Fresnel pattern generated using a biprism excited by a bias voltage. The characteristics of the Fresnel fringes range from a few microns to nanometer spacing as a function of the applied voltage. In this work, we report a variable magnification method for off-axis electron holography using a variable dual-lens system in the objective lens in a JEOL ARM-200F transmission electron microscope that achieves ultra-high resolution. We have applied this technique to compute thickness and inner potentials in metallic and bimetallic nanoparticles. The reliability of the microscope performance with these parameters was validated with the reconstructed phase of the hologram in Au-decahedral nanoparticles in which the topographic shape and 3D visualization have been extracted. In addition, the relationship between strain and chemical composition of bimetallic Au/Pd core-shell nanoparticles has been measured.
PSYCHOLOGY & SOCIAL SCIENCES
ANTHROPOLOGY/ARCHEOLOGYBallroom C - 163
USING A COMMUNITY-GUIDED APPROACH TO IDENTIFY ILLNESSES AND HEALTH CARE CONCERNS OF
UNINSURED MEXICAN IMMIGRANTS ALONG THE US-MEXICO BORDERMilena Melo, Kathryn Fleuriet.
University of Texas at San Antonio, San Antonio, TX.
Hidalgo County in South Texas is one of the most medically underserved areas of the US, characterized by gaps in public health services, poor access to care, significant environmental health concerns, elevated rates of chronic disease, endemic poverty, the highest rate of obesity in the US, and the highest uninsured rate in the country at almost 40%. This pilot project used free-listing and ranking interviews to document the most prevalent self-identified illnesses and health care concerns for low-income Mexican immigrants living in the borderlands of South Texas. Data were derived from semi-structured interviews with 80 uninsured Mexican immigrants in public spaces. The first 50 free-listing interviews allowed participants to generate their own responses to what they perceived were the most serious and prevalent illnesses and health care problems. In the next 30 interviews, participants ranked illnesses and health care issues derived from the free-list interview responses according to their own experiences and then by the larger concerns specific to Hidalgo County. Analysis was guided by the theoretical framework of syndemics. Moreover, data document how this population negotiates illness and accessing health care within the context of extreme poverty, social marginalization, and an increasingly dangerous political landscape. These themes and community-guided health care concerns will guide a dissertation project that will contribute to the anthropology of immigration, human rights and health care, and transnationalism as well as local outreach efforts to improve health and health care in Hidalgo County.
OTHER PYSCHOLOGYBallroom C - 100
THE RELATIONSHIP BETWEEN PERINATAL CHANGES IN SLEEP, DEPRESSION, STRESS, AND BIRTH
OUTCOMES IN PREGNANT MEXICAN-AMERICAN WOMENEsmeralda Garcia, Kimberly D’Anna-Hernandez.
California State University, San Marcos, San Marcos, CA.
Mexican-Americans are the fastest growing population in the US, and Mexican-American women experience adverse perinatal outcomes. It has been suggested that these adverse perinatal outcomes may be related to changes in sleep during pregnancy, but this has yet to be investigated. The present study examined if changes in sleep relate to stress, depression, and other negative perinatal outcomes in pregnant Mexican-American women. It was hypothesized that disruptions in the quality and quantity of sleep would alter levels of depression and stress during pregnancy as well as gestational age and birthweight of offspring. Pregnancy-specific stress levels and depressive symptoms were measured via the New Prenatal Distress Questionnaire Revised and the Edinburgh Postnatal Scale of Depression during early, mid, and late pregnancy in 43 Mexican-American women. Women also self-reported on quantity and quality of sleep in a sleep diary. Correlational analyses revealed that more stress in early and mid pregnancy is associated with less quality of sleep (r = -.33, p =.01) and more hours slept (r =.40, p =.008). Low birthweight was associated with more hours slept in early (r = -.36, p =.02) and mid pregnancy (r = -.37, p =.01), and lower gestational age was related to more stress (r = -.367, p =.01) and less quality of sleep (r =.40, p =.01). Depression was not associated with any perinatal outcomes. The data suggests stress may be a better indicator of adverse outcomes than depression, and variations in sleep patterns and sleep quality early in the prenatal period may affect maternal and infant outcomes.
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EFFORTFUL RETRIEVAL IN TESTING EFFECTAlda Rivas, Jess Logan.
Rice University, Houston, TX.
The testing effect is the finding that retention of information is higher after taking a test than after restudying such information. Previous research has shown increasing support for an “effortful retrieval explanation,” where a higher level of effort to retrieve information during a learning phase will result in higher accurate recall on a final test. In the present study, during the learning phase, participants read four one-page essays and then either reread the essay or took a test. The tests differed in the level of effort required to produce an answer: multiple choice or short answer.