Science.gov

Sample records for aeronautiche tecnam srl

  1. 78 FR 63907 - Airworthiness Directives; Costruzioni Aeronautiche Tecnam srl Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-25

    ... receipt. FOR FURTHER INFORMATION CONTACT: Albert Mercado, Aerospace Engineer, FAA, Small Airplane...; email: albert.mercado@faa.gov . SUPPLEMENTARY INFORMATION: Comments Invited We invite you to send any... Mercado, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City,...

  2. 77 FR 56991 - Airworthiness Directives; Costruzioni Aeronautiche Tecnam srl Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-17

    ...: Albert Mercado, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; phone: (816) 329-4119; fax: (816) 329-4090; email: albert.mercado@faa.gov . SUPPLEMENTARY... information to ATTN: Albert Mercado, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room...

  3. 77 FR 66417 - Airworthiness Directives; Costruzioni Aeronautiche Tecnam srl Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-05

    ... INFORMATION CONTACT: Albert Mercado, Aerospace Engineer, FAA, Small Airplane Directorate, 901 ] Locust, Room....mercado@faa.gov . SUPPLEMENTARY INFORMATION: Comments Invited We invite you to send any written relevant... procedures found in 14 CFR 39.19. Send information to ATTN: Albert Mercado, Aerospace Engineer, FAA,...

  4. 77 FR 35304 - Airworthiness Directives; Costruzioni Aeronautiche Tecnam srl Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-13

    ... available in the AD docket shortly after receipt. FOR FURTHER INFORMATION CONTACT: Albert Mercado, Aerospace...) 329-4119; fax: (816) 329-4090; email: albert.mercado@faa.gov . SUPPLEMENTARY INFORMATION: Comments... found in 14 CFR 39.19. Send information to ATTN: Albert Mercado, Aerospace Engineer, FAA, Small...

  5. 78 FR 14164 - Airworthiness Directives; Costruzioni Aeronautiche Tecnam srl Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-05

    ... the FAA, call (816) 329-4148. FOR FURTHER INFORMATION CONTACT: Albert Mercado, Aerospace Engineer, FAA...- 4119; fax: (816) 329-4090; email: albert.mercado@faa.gov . SUPPLEMENTARY INFORMATION: Discussion We.... Send information to ATTN: Albert Mercado, Aerospace Engineer, FAA, Small Airplane Directorate,...

  6. 76 FR 48045 - Airworthiness Directives; Costruzioni Aeronautiche Tecnam srl Model P2006T Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-08

    ... material at the FAA, call (816) 329-4148; e-mail: albert.mercado@faa.gov . Examining the AD Docket You may... Mercado, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri... found in 14 CFR 39.19. Send information to ATTN: Albert Mercado, Aerospace Engineer, FAA, Small...

  7. 76 FR 18964 - Airworthiness Directives; Costruzioni Aeronautiche Tecnam srl Model P2006T Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-06

    ... after receipt. FOR FURTHER INFORMATION CONTACT: Albert Mercado, Aerospace Engineer, FAA, Small Airplane... 14 CFR 39.19. Send information to ATTN: Albert Mercado, Aerospace Engineer, FAA, Small...

  8. 76 FR 35344 - Airworthiness Directives; Costruzioni Aeronautiche Tecnam srl Model P2006T Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-17

    ...: Albert Mercado, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City... 14 CFR 39.19. Send information to Attn: Albert Mercado, Aerospace Engineer, FAA, Small...

  9. Young Children's Awareness of Self-Regulated Learning (SRL).

    ERIC Educational Resources Information Center

    Hwang, Young Suk; Gorrell, Jeffrey

    Self-regulated learning (SRL) is the process through which individuals direct and sustain their awareness, behaviors, and motivation to optimize their learning or to reach goals. Noting that very little research has been conducted on young children's SRL, this study examined 40 kindergarten children's SRL by investigating: their awareness while…

  10. Pre-Service Teachers' Self-Regulated Learning and Their Developing Concepts of SRL

    ERIC Educational Resources Information Center

    Buzza, Dawn; Allinotte, Trina

    2013-01-01

    Self-regulated learners manage their thoughts, emotions, and behaviours, and their social and contextual environments to reach their learning goals. Research shows that student teachers can learn to teach in ways that promote students' development of SRL. It has also been shown that there is a relationship between teachers' own SRL and their…

  11. Gamma-ray spectrometry of LDEF samples at SRL

    SciTech Connect

    Winn, W.G.

    1991-07-22

    A total of 31 samples from the Long Duration Exposure Facility (LDEF), including materials of aluminum, vanadium, and steel trunnions were analyzed by ultra-low-level gamma spectroscopy. The study quantified particle induced activations of {sup 22}Na, {sup 46}Sc, {sup 51}Cr, {sup 54}Mn, {sup 56}Co, {sup 57}Co, {sup 58}Co, and {sup 60}Co. The samples of trunnion sections exhibited increasing activity toward the outer end of the trunnion and decreasing activity toward its radial center. The trunnion sections did not include end pieces, which have been reported to collect noticeable {sup 7}Be on their leading surfaces. No significant {sup 7}Be was detected in the samples analyzed. The Underground Counting Facility at Savannah River Laboratory (SRL) was used in this work. The facility is 50 ft. underground, constructed with low-background shielding materials, and operated as a clean room. The most sensitive analyses were performed with a 90%-efficient HPGe gamma-ray detector, which is enclosed in a purged active/passive shield. Each sample was counted for one to six days in two orientations to yield more representative average activities for the sample. The non-standard geometries of the LDEF samples prompted the development of a novel calibration method, whereby the efficiency about the samples surfaces (measured with point sources) predicted the efficiency for the bulk sample.

  12. A Qualitative Account of the Nature and Use of Self-Regulated Learning (SRL) Strategies Employed by University Students

    ERIC Educational Resources Information Center

    Alvi, Effat; Iqbal, Zafar; Masood, Fatima; Batool, Tooba

    2016-01-01

    Students' conceptions of how they initiate, plan, implement and monitor self-regulated learning (SRL) strategies have practical implications for teaching and learning. This study explores the nature and use of SRL strategies employed by university students as it occurs in naturalistic settings, for example, studying in non-classroom environments.…

  13. Discovering the Effects of Metacognitive Prompts on the Sequential Structure of SRL-Processes Using Process Mining Techniques

    ERIC Educational Resources Information Center

    Sonnenberg, Christoph; Bannert, Maria

    2015-01-01

    According to research examining self-regulated learning (SRL), we regard individual regulation as a specific sequence of regulatory activities. Ideally, students perform various learning activities, such as analyzing, monitoring, and evaluating cognitive and motivational aspects during learning. Metacognitive prompts can foster SRL by inducing…

  14. Endeavour and its SRL-1 payload backdropped against the Southern Lights

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Part of the Space Shuttle Endeavour and its Space Radar Laboratory (SRL-1) payload are backdropped against a colorful display of the Southern Lights (aurora australis). The vehicle was firing a reaction control subsystem thruster (below center) when the 35mm image was exposed.

  15. International Society for Advancement of Cytometry (ISAC) flow cytometry shared resource laboratory (SRL) best practices.

    PubMed

    Barsky, Lora W; Black, Michele; Cochran, Matthew; Daniel, Benjamin J; Davies, Derek; DeLay, Monica; Gardner, Rui; Gregory, Michael; Kunkel, Desiree; Lannigan, Joanne; Marvin, James; Salomon, Robert; Torres, Carina; Walker, Rachael

    2016-11-01

    The purpose of this document is to define minimal standards for a flow cytometry shared resource laboratory (SRL) and provide guidance for best practices in several important areas. This effort is driven by the desire of International Society for the Advancement of Cytometry (ISAC) members in SRLs to define and maintain standards of excellence in flow cytometry, and act as a repository for key elements of this information (e.g. example SOPs/training material, etc.). These best practices are not intended to define specifically how to implement these recommendations, but rather to establish minimal goals for an SRL to address in order to achieve excellence. It is hoped that once these best practices are established and implemented they will serve as a template from which similar practices can be defined for other types of SRLs. Identification of the need for best practices first occurred through discussions at the CYTO 2013 SRL Forum, with the most important areas for which best practices should be defined identified through several surveys and SRL track workshops as part of CYTO 2014. © 2016 International Society for Advancement of Cytometry.

  16. Synthesis and characterization of a PAMAM dendrimer nanocarrier functionalized by SRL peptide for targeted gene delivery to the brain.

    PubMed

    Zarebkohan, Amir; Najafi, Farhood; Moghimi, Hamid Reza; Hemmati, Mohammad; Deevband, Mohammad Reza; Kazemi, Bahram

    2015-10-12

    Blood-brain barrier inhibits most of drugs and genetic materials from reaching the brain. So, developing high efficiency carriers for gene and drug delivery to the brain, is the challenging area in pharmaceutical sciences. This investigation aimed to target DNA to brain using Serine-Arginine-Leucine (SRL) functionalized PAMAM dendrimers as a novel gene delivery system. The SRL peptide was linked on G4 PAMAM dendrimers using bifunctional PEG. DNA was then loaded in these functionalized nanoparticles and their physicochemical properties and cellular uptake/distribution evaluated by AFM, NMR, FTIR and fluorescence and confocal microscopy. Also, biodistribution and brain localization of nanoparticles were studied after IV injection of nanoparticles into rat tail. Unmodified nanoparticles were used as control in all evaluations. In vitro studies showed that SRL-modified nanoparticles have good transfection efficacy and low toxicity. Results also showed that SRL is a LRP ligand and SRL-modified nanoparticles internalized by clathrin/caveolin energy-dependent endocytosis to brain capillary endothelial cells. After intravenous administration, the SRL-modified nanoparticles were able to cross the blood-brain barrier and enter the brain parenchyma. Our result showed that, SRL-modified nanoparticles provide a safe and effective nanocarrier for brain gene delivery.

  17. Results from the long-term interaction and modeling of SRL-131 glass with aqueous solutions

    SciTech Connect

    Strachan, D.M.; Pederson, L.R.; Lokken, R.O.

    1985-11-01

    Leaching studies on SRL-131 simulated defense waste glass have been carried out for a duration of two years. This glass contained nonradioactive elements and depleted uranium to simulate the waste content. The leachants used in this study were deionized water, a sodium bicarbonate/silicic acid solution (silicate water), a synthetic groundwater, and a high ionic strength K-Mg-Na-Cl brine. Two temperatures were used: 40/sup 0/C and 90/sup 0/C. The long-term results were in fair agreement with modeling calculations performed using the PHREEQE geochemical code. The leachability of SRL-131 glass from results up to two years followed the trend: deionized water > silicate water > synthetic groundwater > salt brine at 40/sup 0/C and deionized water approx. = synthetic groundwater > silicate water > salt brine at 90/sup 0/C. Solid state analyses are reported along with an Appendix containing a complete data set.

  18. The concentration of radionuclides and metals in vegetation adjacent to and in the SRL Seepage Basins

    SciTech Connect

    Murphy, C. E. Jr.

    1992-12-14

    In 1991 the trees on the dikes surrounding the SRL Seepage Basins were sampled and analyzed to inventory the contaminants transported from the basins into the vegetation. Tree leaves and wood were collected and analyzed for {sup 90}Sr, {sup 60}Co, {sup 137}Cs, {sup 238}Pu, {sup 239,240}Pu, {sup 242,244}Cm, {sup 241}Am, Ba, Cr, Hg, Mg, Mn, Ni, and Pb. The concentrations of contaminants were influenced by sample type (leaves versus wood), species type (pines versus hardwoods), and location relative to distance from the basin. The total inventory of each contaminant in the trees was estimated. The relationships between leaf and wood, pines and hardwood, location, and mass of the material in each of these classes were used to weight the total inventory estimate. The radionuclide with the largest inventory was 0.7 mCi for {sup 90}Sr. The metallic contaminant with the largest inventory was Mn at 200 gm.

  19. The concentration of radionuclides and metals in vegetation adjacent to and in the SRL Seepage Basins

    SciTech Connect

    Murphy, C. E. Jr.

    1992-12-14

    In 1991 the trees on the dikes surrounding the SRL Seepage Basins were sampled and analyzed to inventory the contaminants transported from the basins into the vegetation. Tree leaves and wood were collected and analyzed for [sup 90]Sr, [sup 60]Co, [sup 137]Cs, [sup 238]Pu, [sup 239,240]Pu, [sup 242,244]Cm, [sup 241]Am, Ba, Cr, Hg, Mg, Mn, Ni, and Pb. The concentrations of contaminants were influenced by sample type (leaves versus wood), species type (pines versus hardwoods), and location relative to distance from the basin. The total inventory of each contaminant in the trees was estimated. The relationships between leaf and wood, pines and hardwood, location, and mass of the material in each of these classes were used to weight the total inventory estimate. The radionuclide with the largest inventory was 0.7 mCi for [sup 90]Sr. The metallic contaminant with the largest inventory was Mn at 200 gm.

  20. Self-Regulated Learning (SRL) and the Gifted Learner in Primary School: The Theoretical Basis and Empirical Findings on a Research Program Dedicated to Ensuring That All Students Learn to Regulate Their Own Learning

    ERIC Educational Resources Information Center

    Stoeger, Heidrun; Fleischmann, Sandra; Obergriesser, Stefanie

    2015-01-01

    After defining self-regulated learning (SRL), explaining its importance for all ability groups, and summarizing findings on gifted learners' scarcer use of and lower preference for SRL, we describe two instructional modules designed for teaching SRL during regular classroom instruction and homework. We then explain how the modules are…

  1. Reaction of glass during gamma irradiation in a saturated tuff environment. Part 1. SRL 165 glass

    SciTech Connect

    Bates, J.K.; Fischer, D.F.; Gerding, T.J.

    1986-02-01

    The influence of gamma irradiation on the reaction of actinide-doped borosilicate glass (SRL 165) in a saturated tuff environment has been studied in a series of tests lasting up to 56 days. The following conclusions were reached. The reaction of, and subsequent actinide release from, the glass depends on the dynamic interaction between radiolysis effects, which cause the solution pH to become more acidic; glass reaction, which drives the pH more basic; and test component interactions that may extract glass components from solution. The use of large gamma irradiation dose rates to accelerate reactions that may occur in an actual repository radiation field may affect this dynamic balance by unduly influencing the mechanism of the glass-water reaction. Comparisons between the present results and data obtained by reacting similar glasses using MCC-1 and NNWSI rock cup procedures indicate that the irradiation conditions used in the present experiments do not dramatically influence the reaction rate of the glass. 8 figs., 9 tabs.

  2. A Macro-Level Analysis of SRL Processes and Their Relations to the Acquisition of a Sophisticated Mental Model of a Complex System

    ERIC Educational Resources Information Center

    Greene, Jeffrey Alan; Azevedo, Roger

    2009-01-01

    In this study, we used think-aloud verbal protocols to examine how various macro-level processes of self-regulated learning (SRL; e.g., planning, monitoring, strategy use, handling of task difficulty and demands) were associated with the acquisition of a sophisticated mental model of a complex biological system. Numerous studies examine how…

  3. SRL-Coated PAMAM Dendrimer Nano-Carrier for Targeted Gene Delivery to the Glioma Cells and Competitive Inhibition by Lactoferrin

    PubMed Central

    zarebkohan, Amir; Najafi, Farhood; Moghimi, Hamid Reza; Hemmati, Mohammad; Deevband, Mohammad Reza; Kazemi, Bahram

    2016-01-01

    Glioma, as a primary tumor of central nervous system, is the main cause of death in patients with brain cancer. Therefore, development of an efficient strategy for treatment of glioma is worthy. The aim of the current study was to develop a SRL peptide-coated dendrimer as a novel dual gene delivery system for targeting the LRP receptor, an up-regulated gene in both BBB and glioma cells. To perform this investigation, our newly developed nanocarrier (PAMAM-PEG-SRL) was used for gene delivery to C6 glioma cell lines. DNA (GFP) was loaded in these functionalized nanoparticles and their cellular uptake/distribution and gene transfection efficacy was evaluated by fluorescence and confocal microscopy. In vitro studies showed that SRL-modified nanoparticles have good transfection efficacy. Results revealed improved gene transfection efficiency of newly-synthesized delivery system. We also found that lactoferrin, as a LRP ligand, reduced the gene transfection efficacy of the delivery system due to its higher affinity compared to SRL peptides (Competitive inhibition). The present results suggest that the synthesized delivery system has the potential to be used as an alternative targeted drug delivery system for brain tumors. PMID:28243262

  4. SRL in-situ tests in the United Kingdom: Part 2, Surface analyses of SRS waste glass buried for one and two years in limestone at Ballidon, UK

    SciTech Connect

    Namboodri, C.G. Jr.; Wicks, G.G.

    1991-02-26

    A multiphase experimental program to assess and understand waste glass behavior under a wide range of conditions has been in progress at the Savannah River Laboratory (SRL) for over a decade. An important part of this experimental effort is to assess the effects of repository relevant conditions on performance of SRS waste glass, in both controlled laboratory tests, as well as in actual field experiments. In laboratory test, SRS waste glass, simulated and in many cases also fully radioactive, has been tested in environments of salt, basalt, shale, granite, clay and tuff. In field experiments, there are four joint international programs being conducted in four different countries, involving burial of SRS simulated waste glass in granite, limestone, clay and salt geologies. This report discusses the SRS waste glass studies in limestone at Ballidon, UK..

  5. Activity in SRL Nagoya Coated Conductor Center for YBCO Coated Conductor by IBAD+ PLD Method -Long, high Ic conductor and a new bamboo-like nanostructure for efficient pinning

    SciTech Connect

    Yamada, Yutaka; Ibi, Akira; Fukushima, Hiroyuki; Kuriki, Reiji; Takahashi, Kazuhiro; Kobayashi, Hiroyoshi; Ishida, Satoru; Konishi, Masaya; Miyata, Seiki; Watanabe, Tomonori; Kato, Takeharu; Hirayama, Tsukasa; Shiohara, Yuh

    2006-03-31

    In SRL-Nagoya Coated Conductor Center (NCCC), long buffered substrate tapes and YBCO coated conductors have been successfully fabricated by using ion-beam assisted deposition (IBAD) and pulsed laser deposition (PLD) methods. For the buffered tape, the PLD-CeO2 method, what we call the 'Self-Epitaxial' method, realized the high degree of in-plane texturing around 4 degrees along the length of 220 m. For YBCO deposition, we have recently introduced new reel-to-reel PLD equipment with a multi-plume and multi-turn deposition system (MPMT PLD). This system succeeded in fabricating a long coated conductor with a high critical current, Ic, of 245 A and length of 212 m. Ic xL (length) reached the world record of 51940 Am. Furthermore, the introduction of artificial pinning center and RE 123 materials were also studied for improving flux pinning and enhancing Ic. A new columnar structure of the 'bamboo structure' (BaZrO3/Y123 layer-stacked structure) was found in Y123+YSZ sample. This columnar structure and the stacking faults in Gd123 were found to be effective for enhancing pinning properties. Using these techniques, we have succeeded in increasing Ic at 0 T to 480 A/cm and also enhancing Ic in a magnetic field.

  6. Gamma ray spectrometry of LDEF samples at SRL

    NASA Technical Reports Server (NTRS)

    Winn, Willard G.

    1992-01-01

    A total of 31 samples from the Long Duration Exposure Facility (LDEF), including materials of aluminum, vanadium, and steel trunnions were analyzed by ultra-low-level gamma spectrometry. The study quantified particle induced activations of Na-22, Sc-46, Cr-51, Mn-54, Co-56, Co-57, Co-58, and Co-60. The samples of trunnion sections exhibited increasing activity toward the outer end of the trunnion and decreasing activity toward its radial center. The trunnion sections did not include end pieces, which were reported to collect noticeable Be-7 on their leading surfaces. No significant Be-7 was detected in the samples analyzed.

  7. Bridging Literacy Acquisition and Self-Regulated Learning: Using a SRL Framework to Support Struggling Readers

    ERIC Educational Resources Information Center

    Holtzheuser, Sierra; McNamara, John

    2014-01-01

    Reading is conceptualized as a hierarchy of component skills where lower order emergent literacy skills set the foundation for higher order reading skills such as fluency and comprehension. Approximately 20% of readers struggle within this hierarchical process (Fielding, Kerr, & Rosier, 2007). Struggling readers are susceptible to the Matthew…

  8. WIPP/SRL in-situ tests: MIIT program--The effects of metal package components

    SciTech Connect

    Covington, J.A.; Wicks, G.G.; Molecke, M.A.

    1991-12-31

    The Materials Interface Interactions Tests or MIIT is the largest in-situ testing program in progress, involving burial of many simulated nuclear waste systems and accompanying package components. In MIIT, waste glass samples were fabricated into the shape of `pineapple slices`, polished on one side. Proposed package components were also made into a similar configuration and the various glasses, metals, and geologic samples were than stacked onto heater elements within Teflon assemblies. This produced interactions of interest by creating glass/glass, glass/salt, and glass/metal interfaces. Since the outer diameter of the metal was smaller than the outer diameter of the glass, a lip was created which was also produced a glass/liquid interface, which was also studied. Overall, a total of 50 stacks or assemblies of pineapple slices were created in seven different stacking arrangements. Each individual assembly was then installed in an instrumented borehole at WIPP. Brine was then added to most of boreholes and the assemblies heated and maintained at 90{degrees}C. This was achieved by energizing the central heating and rod that traversed through the middle opening of each of the pineapple slices in each assembly. Due to the design of these units, glass, metal and geologic samples could be removed at time intervals of 6 mos., 1 year, 2 years, and 5 years. Currently, all but the 5 year samples have been removed from test and are being evaluated in laboratories of MIIT participants.

  9. WIPP/SRL in-situ tests: MIIT program--The effects of metal package components

    SciTech Connect

    Covington, J.A. ); Wicks, G.G. ); Molecke, M.A. )

    1991-01-01

    The Materials Interface Interactions Tests or MIIT is the largest in-situ testing program in progress, involving burial of many simulated nuclear waste systems and accompanying package components. In MIIT, waste glass samples were fabricated into the shape of pineapple slices', polished on one side. Proposed package components were also made into a similar configuration and the various glasses, metals, and geologic samples were than stacked onto heater elements within Teflon assemblies. This produced interactions of interest by creating glass/glass, glass/salt, and glass/metal interfaces. Since the outer diameter of the metal was smaller than the outer diameter of the glass, a lip was created which was also produced a glass/liquid interface, which was also studied. Overall, a total of 50 stacks or assemblies of pineapple slices were created in seven different stacking arrangements. Each individual assembly was then installed in an instrumented borehole at WIPP. Brine was then added to most of boreholes and the assemblies heated and maintained at 90{degrees}C. This was achieved by energizing the central heating and rod that traversed through the middle opening of each of the pineapple slices in each assembly. Due to the design of these units, glass, metal and geologic samples could be removed at time intervals of 6 mos., 1 year, 2 years, and 5 years. Currently, all but the 5 year samples have been removed from test and are being evaluated in laboratories of MIIT participants.

  10. Development of glass vitrification at SRL as a waste treatment technique for nuclear weapon components

    SciTech Connect

    Coleman, J.T.; Bickford, D.F.

    1991-01-01

    This report discusses the development of vitrification for the waste treatment of nuclear weapons components at the Savannah River Site. Preliminary testing of surrogate nuclear weapon electronic waste shows that glass vitrification is a viable, robust treatment method.

  11. Development of glass vitrification at SRL as a waste treatment technique for nuclear weapon components

    SciTech Connect

    Coleman, J.T.; Bickford, D.F.

    1991-12-31

    This report discusses the development of vitrification for the waste treatment of nuclear weapons components at the Savannah River Site. Preliminary testing of surrogate nuclear weapon electronic waste shows that glass vitrification is a viable, robust treatment method.

  12. A femtosecond stimulated Raman loss (fSRL) microscope for highly sensitive bond-selective imaging

    NASA Astrophysics Data System (ADS)

    Zhang, Delong; Slipchenko, Mikhail N.; Yue, Shuhua; Li, Junjie; Cheng, Ji-Xin

    2011-03-01

    We demonstrate nonlinear vibrational imaging of isolated Raman bands by detecting femtosecond pulse stimulated Raman loss. Femtosecond pulse excitation produces a stimulated Raman loss signal that is 12 times larger than what picosecond pulse excitation produces. The strong signal allowed real-time, bond-selective imaging of deuterated palmitic acid-d31 inside live cells, and 3D sectioning of fat storage in live C. elegans. With the high peak power provided by femtosecond pulses, this system is highly compatible with other nonlinear optical modalities such as two-photon excited fluorescence. With most of the excitation power contributed by the Stokes beam in the 1.0 - 1.2 μm wavelength range, photodamage of biological samples was not observed.

  13. 44 CFR 79.7 - Offers and appeals under the SRL program.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... required non-Federal sources, would not cover the actual eligible costs of the mitigation activity... integrity of a historic district, site, building, or object's significant historic characteristics to the extent where the historic resource would lose its status as listed or eligible for inclusion on...

  14. Redox calcination study of Synroc D powder containing simulated SRL waste

    SciTech Connect

    Chen, C.

    1982-07-27

    According to Ringwood (A.E. Ringwood, W. Sinclair, and G.M. McLaughlin, Nuclear Waste Immobilization, Lawrence Livermore Laboratory, Livermore, Rept. UCRL-15147 (1979)), the iron oxidation state is important in controlling, the spinel mineralogy and composition if the amount of titania (TiO/sub 2/) consumed in spinel formation is to be minimized in favor of the formation of the Synroc phases, zirconolite, perovskite, and nepheline. In our redox calcination studies we observed that the iron oxidation state of FeO/Fe/sub 2/O/sub 3/ can be controlled by the redoxcalcining atmosphere. In a CO atmosphere, the oxidation state was reduced to less than 7 wt % Fe/sub 2/O/sub 3/. With appropriate CO/sub 2//CO gas mixtures the resultant iron oxidation states were in the range of 45 to 59 wt % Fe/sub 2/O/sub 3/. Direct rotary redox calcination of spray dried powder at 600/sup 0/C, without prior air calcination, showed increased redox efficiency when compared to powder that had been previously air calcined at 650/sup 0/C. We believe this is caused by a reduction in particle size. Rotary calcination at 800/sup 0/C in argon has no measurable reduction affect on the iron oxidation state of Synroc D powder.

  15. Design and cost estimate for the SRL integrated hot off gas facility using selective adsorption

    SciTech Connect

    Pence, D T; Kirstein, B E

    1981-07-01

    Based on the results of an engineering-scale demonstration program, a design and cost estimate were performed for a 25-m/sup 3//h (15-ft/sup 3//min) capacity pilot plant demonstration system using selective adsorption technology for installation at the Integrated Hot Off Gas Facility at the Savannah River Plant. The design includes provisions for the destruction of NO/sub x/ and the concentration and removal of radioisotopes of ruthenium, iodine-129, tritiated water vapor, carbon-14 contaminated carbon dioxide, and krypton-85. The nobel gases are separated by the use of selective adsorption on mordenite-type zeolites. The theory of noble gas adsorption on zeolites is essentially the same as that for the adsorption of noble gases on activated charcoals. Considerable detail is provided regarding the application of the theory to adsorbent bed designs and operation. The design is based on a comprehensive material balance and appropriate heat transfer calculations. Details are provided on techniques and procedures used for heating, cooling, and desorbing the adsorbent columns. Analyses are also given regarding component and arrangement selection and includes discussions on alternative arrangements. The estimated equipment costs for the described treatment system is about $1,400,000. The cost estimate includes a detailed equipment list of all the major component items in the design. Related technical issues and estimated system performance are also discussed.

  16. 44 CFR 79.7 - Offers and appeals under the SRL program.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., timeframes, and the consequences of refusing such offer. For open space acquisitions, it will also include... applicable to the property. The increases shall end when the actuarial rate is reached. (2) Upon each renewal... sufficient funds are available. (d) Appeals of insurance rate increases. Any owner of a severe...

  17. 44 CFR 79.7 - Offers and appeals under the SRL program.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., timeframes, and the consequences of refusing such offer. For open space acquisitions, it will also include... applicable to the property. The increases shall end when the actuarial rate is reached. (2) Upon each renewal... sufficient funds are available. (d) Appeals of insurance rate increases. Any owner of a severe...

  18. Toward a Treatment Effect of an Intervention to Foster Self-Regulated Learning (SRL): An Application of the Rasch Model

    ERIC Educational Resources Information Center

    Reeves, Todd Douglas

    2009-01-01

    This study investigated whether an intervention measurably contributed to the self-regulatory processes underlying undergraduate students' learning. The Rasch model was first applied to Dynamic and Active Learning Inventory Revised (DALI-R; Iran-Nejad & Chissom, 1992) data to examine the validity of inferences made from this instrument and to…

  19. Proceedings of the first SRL model validation workshop. [Comparison and evaluation of atmospheric dispersion models using data for Kr-85

    SciTech Connect

    Buckner, M.R.

    1981-10-01

    The Clean Air Act and its amendments have added importance to knowing the accuracy of mathematical models used to assess transport and diffusion of environmental pollutants. These models are the link between air quality standards and emissions. To test the accuracy of a number of these models, a Model Validation Workshop was held. The meteorological, source-term, and Kr-85 concentration data bases for emissions from the separations areas of the Savannah River Plant during 1975 through 1977 were used to compare calculations from various atmospheric dispersion models. The results of statistical evaluation of the models show a degradation in the ability to predict pollutant concentrations as the time span over which the calculations are made is reduced. Forecasts for annual time periods were reasonably accurate. Weighted-average squared correlation coefficients (R/sup 2/) were 0.74 for annual, 0.28 for monthly, 0.21 for weekly, and 0.18 for twice-daily predictions. Model performance varied within each of these four categories; however, the results indicate that the more complex, three-dimensional models provide only marginal increases in accuracy. The increased costs of running these codes is not warranted for long-term releases or for conditions of relatively simple terrain and meteorology. The overriding factor in the calculational accuracy is the accurate description of the wind field. Further improvements of the numerical accuracy of the complex models is not nearly as important as accurate calculations of the meteorological transport conditions.

  20. MIIT: International in-situ testing of simulated HLW forms--preliminary analyses of SRL 165/TDS waste glass and metal systems

    SciTech Connect

    Wicks, G.G.; Lodding, A.R.; Macedo, P.B.; Clark, D.E.; Molecke, M.A.

    1989-12-31

    The first in-situ tests involving burial of simulated high-level waste (HLW) forms conducted in the United States were started on July 22, 1986. This effort, called the Materials Interface Interactions Tests (MIIT), comprises the largest, most cooperative field testing venture in the international waste management community. Included in the study are over 900 waste form samples comprising 15 different systems supplied by seven countries. Also included are almost 300 potential canister or overpack metal samples of 11 different metals along with more than 500 geologic and backfill specimens. There are a total of 1926 relevant interactions that characterize this effort which is being conducted in the bedded salt site at the Waste Isolation Pilot Plant (WIPP), near Carlsbad, New Mexico.

  1. MIIT: International in-situ testing of simulated HLW forms--preliminary analyses of SRL 165/TDS waste glass and metal systems

    SciTech Connect

    Wicks, G.G. ); Lodding, A.R. ); Macedo, P.B. . Vitreous State Lab.); Clark, D.E. ); Molecke, M.A. )

    1989-01-01

    The first in-situ tests involving burial of simulated high-level waste (HLW) forms conducted in the United States were started on July 22, 1986. This effort, called the Materials Interface Interactions Tests (MIIT), comprises the largest, most cooperative field testing venture in the international waste management community. Included in the study are over 900 waste form samples comprising 15 different systems supplied by seven countries. Also included are almost 300 potential canister or overpack metal samples of 11 different metals along with more than 500 geologic and backfill specimens. There are a total of 1926 relevant interactions that characterize this effort which is being conducted in the bedded salt site at the Waste Isolation Pilot Plant (WIPP), near Carlsbad, New Mexico.

  2. 75 FR 65383 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Telemanagement Forum

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-22

    ... De Telecommunicaciones De Bogota S.A.E.S.P, Bogota, COLOMBIA; e-Stratega S.R.L., Olivos, Buenos Aires..., UNITED KINGDOM; RiverMuse, London, UNITED KINGDOM; RRD SRL--Reti Radiotelevisive Digitali Srl, Milano,...

  3. Effective Self-Regulatory Processes in Higher Education: Research Findings and Future Directions. A Systematic Review

    ERIC Educational Resources Information Center

    de Bruijn-Smolders, Monique; Timmers, Caroline F.; Gawke, Jason C. L.; Schoonman, Wouter; Born, Marise Ph.

    2016-01-01

    Although self-regulated learning (SRL) is assumed to benefit learning outcomes, gaps in the literature make it difficult to describe what constitutes effective SRL in higher education. That is, SRL that relates positively to learning outcomes. In accordance, at present it is unclear how to train effective SRL in higher education. The current…

  4. Enabling Electric Propulsion for Flight

    NASA Technical Reports Server (NTRS)

    Ginn, Starr Renee

    2015-01-01

    Team Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project, sub-project Convergent Electric Propulsion Technologies AFRC, LaRC and GRC, re-winging a 4 passenger Tecnam aircraft with a 31ft distributed electric propulsion wing. Advanced Air Transport Technologies (Fixed Wing), Hybrid Electric Research Theme, developing a series hybrid ironbird and flight sim to study integration and performance challenges in preparation for a 1-2 MW flight project.

  5. Enabling Electric Propulsion for Flight

    NASA Technical Reports Server (NTRS)

    Ginn, Starr

    2014-01-01

    Description of current ARMD projects; Team Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project (new ARMD reorg), sub-project Convergent Electric Propulsion Technologies AFRC, LaRC and GRC, re-winging a 4 passenger Tecnam aircraft with a 31ft distributed electric propulsion wing. Advanced Air Transport Technologies (Fixed Wing), Hybrid Electric Research Theme, developing a series hybrid ironbird and flight sim to study integration and performance challenges in preparation for a 1-2 MW flight project.

  6. Understanding Student Coregulation in Task Interpretation during Electronics Laboratory Activities

    ERIC Educational Resources Information Center

    Rivera-Reyes, Presentacion; Lawanto, Oenardi; Pate, Michale L.

    2016-01-01

    Coregulation (CRL) is a transitional process in which students share problem-solving techniques and utilize self-regulated learning (SRL) when interacting with peers. Coregulation may help students to define and modify inconsistencies in their SRL strategy. Task interpretation is described as the critical first step in the SRL process, and it is a…

  7. Third Wave of Measurement in the Self-Regulated Learning Field: When Measurement and Intervention Come Hand in Hand

    ERIC Educational Resources Information Center

    Panadero, Ernesto; Klug, Julia; Järvelä, Sanna

    2016-01-01

    Measurement is a central issue for the self-regulated learning (SRL) field as SRL is a phenomenon difficult to measure in a reliable and valid way. Here, 3 waves in the history of SRL measurement are identified and profiled. Our focus lies on the third and newest one, which combines measurement and intervention within the same tools. The basis for…

  8. College Student Success Course Takers' Perceptions of College Student Effectiveness

    ERIC Educational Resources Information Center

    Hoops, Leah D.; Artrip, Ashley

    2016-01-01

    College student success courses are designed to help students develop effective self-regulating learning (SRL) skills. Little research has examined students' perceptions of SRL at course end. The purpose of this study was to examine student perceptions of "what makes an effective college student" in regards to SRL after course…

  9. The Use of Self-Regulation Strategies by Foreign Language Learners and Its Role in Language Achievement

    ERIC Educational Resources Information Center

    Seker, Meral

    2016-01-01

    Studies show that incorporating self-regulated learning (SRL) strategies into foreign language teaching encourages the development of autonomous learners. However, interviews with teachers (n = 51) indicate that they mostly do not consider SRL in classroom practices. The present study attempts to highlight the significance of SRL in language…

  10. Self-Regulated Learning Ability of Chinese Distance Learners

    ERIC Educational Resources Information Center

    Zhao, Hong; Chen, Li; Panda, Santosh

    2014-01-01

    This study reports on self-regulated learning (SRL) of Chinese distance learners by using a structured SRL scale. SRL of adult and lifelong learners is a well-researched area, though its application within distance education is a new area of investigation. Open and distance learning lean heavily on self-learning and self-learning resources, though…

  11. Children's Self-Regulated Learning Profile in Language and Mathematics: The Role of Task Value Beliefs

    ERIC Educational Resources Information Center

    Metallidou, Panayiota; Vlachou, Anastasia

    2010-01-01

    This study explored the self-regulated learning (SRL) profile of upper elementary (fifth and sixth grade) school children who were differentiated in their task value beliefs (low and high) in language and mathematics. Students' SRL profile involved their teachers' ratings of achievement outcomes and SRL behaviors. The subscale of task value…

  12. Re-Evaluating and Exploring the Contributions of Constituency Grammar to Semantic Role Labeling

    ERIC Educational Resources Information Center

    Yang, Li

    2009-01-01

    Since the seminal work of Gildea and Jurafsky (2000), semantic role labeling (SRL) researchers have been trying to determine the appropriate syntactic/semantic knowledge and statistical algorithms to tackle the challenges in SRL. In search of the appropriate knowledge, SRL researchers shifted from constituency grammar to dependency grammar around…

  13. Student Conscientiousness, Self-Regulated Learning, and Science Achievement: An Explorative Field Study

    ERIC Educational Resources Information Center

    Eilam, Billie; Zeidner, Moshe; Aharon, Irit

    2009-01-01

    This explorative field study examined the mediating role of self-regulated learning (SRL) in the relationship between the personality trait of conscientiousness, SRL, and science achievement in a sample of junior high school students. Over the course of an entire academic year, data on enacted SRL were collected each week for 52 eighth-grade…

  14. Influence of Family Environment on the Students' Use of Self-Regulated Learning Strategies

    ERIC Educational Resources Information Center

    Kadhiravan, S.

    2011-01-01

    Recently researchers have begun to study empirically the role of the personal attributes of students and psychological processes underlying their learning and academic performance. One such aspect is known as Self-Regulation in Learning (SRL). Self-regulated learning (SRL) is a cognitively inherent aspect of learning. SRL is a deliberate,…

  15. Self-Regulation of Learning with Computer-Based Learning Environments

    ERIC Educational Resources Information Center

    Greene, Jeffrey A.; Moos, Daniel C.; Azevedo, Roger

    2011-01-01

    Self-regulated learning (SRL) skills are enacted dynamically over the course of learning tasks, and the frequency and quality of their use can fluctuate dramatically. Further, students' SRL skills can vary from one academic domain to another and even from one task to another within a single domain. Thus, while SRL skills are essential for…

  16. Flipping the Classroom: Embedding Self-Regulated Learning Prompts in Videos

    ERIC Educational Resources Information Center

    Moos, Daniel C.; Bonde, Caitlin

    2016-01-01

    This study examined the effectiveness of embedding self-regulated learning (SRL) prompts in a video designed for the flipped class model. The sample included 32 undergraduate participants who were randomly assigned to one of two conditions: control (video) or experimental (video + SRL prompts). Prior knowledge was measured with a pre-test, SRL was…

  17. Self-Regulated Learning and Executive Function: Exploring the Relationships in a Sample of Adolescent Males

    ERIC Educational Resources Information Center

    Effeney, Gerard; Carroll, Annemaree; Bahr, Nan

    2013-01-01

    This study investigated relationships between SRL and EF in a sample of 254 school-aged adolescent males. Two hypotheses were tested: that self-reported measures of SRL and EF are closely related and that as different aspects of EF mature during adolescence, the corresponding components of SRL should also improve, leading to an age-related…

  18. Nicorandil prevents sirolimus-induced production of reactive oxygen species, endothelial dysfunction, and thrombus formation.

    PubMed

    Aizawa, Ken; Takahari, Youko; Higashijima, Naoko; Serizawa, Kenichi; Yogo, Kenji; Ishizuka, Nobuhiko; Endo, Koichi; Fukuyama, Naoto; Hirano, Katsuya; Ishida, Hideyuki

    2015-03-01

    Sirolimus (SRL) is widely used to prevent restenosis after percutaneous coronary intervention. However, its beneficial effect is hampered by complications of thrombosis. Several studies imply that reactive oxygen species (ROS) play a critical role in endothelial dysfunction and thrombus formation. The present study investigated the protective effect of nicorandil (NIC), an anti-angina agent, on SRL-associated thrombosis. In human coronary artery endothelial cells (HCAECs), SRL stimulated ROS production, which was prevented by co-treatment with NIC. The preventive effect of NIC on ROS was abolished by 5-hydroxydecanoate but not by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one. NIC also inhibited SRL-induced up-regulation of NADPH oxidase subunit p22(phox) mRNA. Co-treatment with NIC and SRL significantly up-regulated superoxide dismutase 2. NIC treatment significantly improved SRL-induced decrease in viability of HCAECs. The functional relevance of the preventive effects of NIC on SRL-induced ROS production and impairment of endothelial viability was investigated in a mouse model of thrombosis. Pretreatment with NIC inhibited the SRL-induced acceleration of FeCl3-initiated thrombus formation and ROS production in the testicular arteries of mice. In conclusion, NIC prevented SRL-induced thrombus formation, presumably due to the reduction of ROS and to endothelial protection. The therapeutic efficacy of NIC could represent an additional option in the prevention of SRL-related thrombosis.

  19. Performance Evaluation Test of the Orbit Screen Model 68A and the Komplet Model 48-25 Rock Crusher

    DTIC Science & Technology

    2008-08-01

    screen and on a Komplet Italia , s.r.l., Model 48-25 rock crusher. The test was conducted during August 2008 at a U.S. Army test site in central... Italia , s.r.l., Model 48-25 Rock Crusher.......................................................... 2 2.3 ASV SR-80 Rubber-Tracked Skid-Steer Loader... Italia , s.r.l., Rock Crusher Testing ......................................................................... 16 5.1 Crushing Performance Test

  20. 44 CFR 79.3 - Responsibilities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... mitigation planning, mitigation project activities, developing subgrant applications, and implementing... State POC for FMA planning, project and management cost subgrants, and for SRL project and...

  1. Pharmacokinetics, biodistribution and antitumour effects of Sclerotium rolfsii lectin in mice.

    PubMed

    Anupama, S; Laha, Preeti; Sharma, Mamta; Pathak, Kamal; Bane, Sanjay; Ingle, Arvind D; Gota, Vikram; Kalraiya, Rajiv D; Yu, Lu-Gang; Rhodes, Jonathan M; Swamy, Bale M; Inamdar, Shashikala R

    2017-04-03

    Sclerotium rolfsii lectin (SRL) is a lectin isolated from the fungus Sclerotium rolfsii and has exquisite binding specificity towards the oncofetal Thomsen-Friedenreich antigen (TF-Ag; Galβ1-3GalNAcα-O-Ser/Thr) and its derivatives. Previous studies have shown that SRL inhibits the proliferation of human colon, breast and ovarian cancer cells in vitro and suppresses tumour growth in mice when introduced intratumourally. The present study assessed the effect of SRL on tumour growth when introduced intraperitoneally in BALB/c nude mice and investigated the pharmacokinetics and biodistribution of SRL in Swiss albino mice. When 9 doses of SRL (30 mg/kg body weight/mice) was administered to BALB/c nude mice bearing human colon cancer HT-29 xenografts, a substantial reduction in tumour size was observed. A 35.8% reduction in tumour size was noted in the treated animals after 17 days. SRL treatment also inhibited angiogenesis, and the tumours from the treated animals were observed to carry fewer blood vessels and express less angiogenesis marker protein CD31, than that from the control animals. Pharmacokinetics and biodistribution analysis revealed that SRL was detected in the serum after 1 h and its level peaked after 24 h. SRL was not detected in any of the organs apart from the kidney where a trace amount was detected after 24 h of SRL injection. No significant changes were observed in any of the biochemical parameters tested including SGOT, SGPT, LDH, CREAT and BUN in the SRL-treated mice compared to these levels in the controls. This suggests that SRL has good potential to be developed as a therapeutic agent for cancer treatment and warrant further investigations in vivo and subsequent clinical trials.

  2. Effects of metformin on hyperglycemia in an experimental model of tacrolimus- and sirolimus-induced diabetic rats

    PubMed Central

    Jin, Jian; Lim, Sun Woo; Jin, Long; Yu, Ji Hyun; Kim, Hyun Seon; Chung, Byung Ha; Yang, Chul Woo

    2017-01-01

    Background/Aims Metformin (MET) is a first-line drug for type 2 diabetes mellitus (DM); its effect on new-onset diabetes after transplantation caused by immunosuppressant therapy is unclear. We compared the effects of MET on DM caused by tacrolimus (TAC) or sirolimus (SRL). Methods DM was induced by injection of TAC (1.5 mg/kg) or SRL (0.3 mg/kg) for 2 weeks in rats, and MET (200 mg/kg) was injected for 2 more weeks. The effects of MET on DM caused by TAC or SRL were evaluated using an intraperitoneal glucose tolerance test (IPGTT) and by measuring plasma insulin concentration, islet size, and glucose-stimulated insulin secretion (GSIS). The effects of MET on the expression of adenosine monophosphate-activated protein kinase (AMPK), a pharmacological target of MET, were compared between TAC- and SRL-treated islets. Results IPGTT showed that both TAC and SRL induced hyperglycemia and reduced plasma insulin concentration compared with vehicle. These changes were reversed by addition of MET to SRL but not to TAC. Pancreatic islet cell size was decreased by TAC but not by SRL, but addition of MET did not affect pancreatic islet cell size in either group. MET significantly increased GSIS in SRL- but not in TAC-treated rats. AMPK expression was not affected by TAC but was significantly decreased in SRL-treated islets. Addition of MET restored AMPK expression in SRL-treated islets but not in TAC-treated islets. Conclusions MET has different effects on hyperglycemia caused by TAC and SRL. The discrepancy between these drugs is related to their different mechanisms causing DM. PMID:27688296

  3. 76 FR 48130 - Certain Pasta From Italy: Preliminary Results of the 14th (2009) Countervailing Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-08

    ...'') and Pastificio Antonio Pallante S.r.L. (``Pallante'') received countervailable subsidies and that F... certificate issued by Bioagricert S.r.l. are also excluded from the order. See Memorandum from Eric B. Greynolds to Melissa G. Skinner, dated August 4, 2004, which is on file in the Department's CRU. In...

  4. 76 FR 64897 - Certain Pasta From Italy: Notice of Partial Rescission of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-19

    ... (``PAM''), P.A.P. SNC Di Pazienza G.B. & C. (``P.A.P.''), Premiato Pastificio Afeltra S.r.L. (``Afeltra... Granoro S.R.L. (``Granoro''),\\2\\ Pastificio Di Martino Gaetano & F.lli SpA (``Di Martino''), Pastificio... Riscossa F.lli Mastromauro S.p.A. (``Riscossa''), Rummo S.p.A. Molino e Pastificio (``Rummo''),...

  5. 76 FR 77204 - Certain Pasta From Italy: Notice of Partial Rescission of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-12

    ... (``PAM''), P.A.P. SNC Di Pazienza G.B. & C. (``P.A.P.''), Premiato Pastificio Afeltra S.r.L. (``Afeltra... Granoro S.R.L. (``Granoro''),\\2\\ Pastificio Di Martino Gaetano & F.11i SpA (``Di Martino''), Pastificio... Riscossa F.11i Mastromauro S.p.A. (``Riscossa''), Rummo S.p.A. Molino e Pastificio (``Rummo''),...

  6. Automated, Unobtrusive, Action-by-Action Assessment of Self-Regulation during Learning with an Intelligent Tutoring System

    ERIC Educational Resources Information Center

    Aleven, Vincent; Roll, Ido; McLaren, Bruce M.; Koedinger, Kenneth R.

    2010-01-01

    Assessment of students' self-regulated learning (SRL) requires a method for evaluating whether observed actions are appropriate acts of self-regulation in theEv specific learning context in which they occur. We review research that has resulted in an automated method for context-sensitive assessment of a specific SRL strategy, help seeking while…

  7. Self-Regulation and Gender within a Game-Based Learning Environment

    ERIC Educational Resources Information Center

    Nietfeld, John L.; Shores, Lucy R.; Hoffmann, Kristin F.

    2014-01-01

    In this study, we examined how self-regulated learning (SRL) and gender influences performance in an educational game for 8th-grade students (N = 130). Crystal Island--Outbreak is an immersive, inquiry-based, narrative-centered learning environment featuring a microbiology science mystery aligned with 8th-grade science curriculum. SRL variables…

  8. Self-Regulated Learning Strategies of Engineering College Students While Learning Electric Circuit Concepts with Enhanced Guided Notes

    ERIC Educational Resources Information Center

    Lawanto, Oenardi; Santoso, Harry

    2013-01-01

    The current study evaluated engineering college students' self-regulated learning (SRL) strategies while learning electric circuit concepts using enhanced guided notes (EGN). Our goal was to describe how students exercise SRL strategies and how their grade performance changes after using EGN. Two research questions guided the study: (1) To what…

  9. Fostering Self-Regulated Learning in a Blended Environment Using Group Awareness and Peer Assistance as External Scaffolds

    ERIC Educational Resources Information Center

    Lin, J-W.; Lai, Y-C.; Lai, Y-C.; Chang, L-C.

    2016-01-01

    Most systems for training self-regulated learning (SRL) behaviour focus on the provision of a learner-centred environment. Such systems repeat the training process and place learners alone to experience that process iteratively. According to the relevant literature, external scaffolds are more promising for effective SRL training. In this work,…

  10. Examining the Level of Convergence among Self-Regulated Learning Microanalytic Processes, Achievement, and a Self-Report Questionnaire

    ERIC Educational Resources Information Center

    Cleary, Timothy J.; Callan, Gregory L.; Malatesta, Jaime; Adams, Tanya

    2015-01-01

    This study examined the convergent and predictive validity of self-regulated learning (SRL) microanalytic measures. Specifically, theoretically based relations among a set of self-reflection processes, self-efficacy, and achievement were examined as was the level of convergence between a microanalytic strategy measure and a SRL self-report…

  11. A Framework for Implementing Individualized Self-Regulated Learning Strategies in the Classroom

    ERIC Educational Resources Information Center

    Ness, Bryan M.; Middleton, Michael J.

    2012-01-01

    Self-regulated learning (SRL) is a conceptual model that can be used to design and implement individualized learning strategies for students with learning disabilities. Students who self-regulate their learning engage in planning, performance, and self-evaluation during academic tasks. This article highlights one approach for teaching SRL skills…

  12. Aspects and Prospects of Measuring Studying and Learning in Higher Education

    ERIC Educational Resources Information Center

    Lonka, Kirsti; Olkinuora, Erkki; Makinen, Jarkko

    2004-01-01

    The development of two dominant research traditions is described: students' approaches to learning (SAL) and information processing (IP). The development of the third tradition, self-regulated learning (SRL) is added. SAL is based on European research, whereas IP and SRL are more typical background ideas for North-American research. The most…

  13. Measuring Cognitive and Metacognitive Regulatory Processes during Hypermedia Learning: Issues and Challenges

    ERIC Educational Resources Information Center

    Azevedo, Roger; Moos, Daniel C.; Johnson, Amy M.; Chauncey, Amber D.

    2010-01-01

    Self-regulated learning (SRL) with hypermedia environments involves a complex cycle of temporally unfolding cognitive and metacognitive processes that impact students' learning. We present several methodological issues related to treating SRL as an event and strengths and challenges of using online trace methodologies to detect, trace, model, and…

  14. Investigating How College Students' Task Definitions and Plans Relate to Self-Regulated Learning Processing and Understanding of a Complex Science Topic

    ERIC Educational Resources Information Center

    Greene, Jeffrey A.; Hutchison, Leigh Anna; Costa, Lara-Jeane; Crompton, Helen

    2012-01-01

    Winne and Hadwin (2008) identified four phases of self-regulated learning (SRL) including defining the task, setting goals and making plans, studying (i.e., learning), and adaptation. The vast majority of SRL research has focused on processing during the third phase, studying. In this study, we developed coding rubrics that allowed us to examine…

  15. Issues in Researching Self-Regulated Learning as Patterns of Events

    ERIC Educational Resources Information Center

    Winne, Philip H.

    2014-01-01

    New methods for gathering and analyzing data about events that comprise self-regulated learning (SRL) support discoveries about patterns among events and tests of hypotheses about roles patterns play in learning. Five such methodologies are discussed in the context of four key questions that shape investigations into patterns in SRL. A framework…

  16. Self-Regulated Learning in Technology Enhanced Learning Environments: An Investigation with University Students

    ERIC Educational Resources Information Center

    Lenne, Dominique; Abel, Marie-Helene; Trigano, Philippe; Leblanc, Adeline

    2008-01-01

    In Technology Enhanced Learning Environments, self-regulated learning (SRL) partly relies on the features of the technological tools. The authors present two environments they designed in order to facilitate SRL: the first one (e-Dalgo) is a website dedicated to the learning of algorithms and computer programming. It is structured as a classical…

  17. Self-Regulated Learning: The Role of Motivation, Emotion, and Use of Learning Strategies in Students' Learning Experiences in a Self-Paced Online Mathematics Course

    ERIC Educational Resources Information Center

    Cho, Moon-Heum; Heron, Michele L.

    2015-01-01

    Enrollment in online remedial mathematics courses has increased in popularity in institutions of higher learning; however, students unskilled in self-regulated learning (SRL) find online remedial mathematics courses particularly challenging. We investigated the role of SRL, specifically motivation, emotion, and learning strategies, in students'…

  18. Interactions of Metacognition with Motivation and Affect in Self-Regulated Learning: The MASRL Model

    ERIC Educational Resources Information Center

    Efklides, Anastasia

    2011-01-01

    Metacognition, motivation, and affect are components of self-regulated learning (SRL) that interact. The "metacognitive and affective model of self-regulated learning" (the MASRL model) distinguishes two levels of functioning in SRL, namely, the Person level and the Task x Person level. At the Person level interactions between trait-like…

  19. Self-Regulated Learning Skills and Online Activities between Higher and Lower Performers on a Web-Intensive Undergraduate Engineering Course

    ERIC Educational Resources Information Center

    Lawanto, Oenardi; Santoso, Harry B.; Lawanto, Kevin N.; Goodridge, Wade

    2017-01-01

    The objective of this study was to evaluate students' self-regulated learning (SRL) skills used in a Web-intensive learning environment. The research question guiding the study was: How did the use of student SRL skills and student engagement in online activities compare between higher- and lower-performing students participating in a…

  20. Long-Term Self-Regulation of Biology Learning Using Standard Junior High School Science Curriculum

    ERIC Educational Resources Information Center

    Eilam, Billie; Reiter, Shoshi

    2014-01-01

    In today's world of information explosion, independent lifelong self-regulated learning (SRL) is becoming a necessity. However, opportunities in schools to experience such learning modes are relatively rare. This long-term explorative field study examined students' SRL of science. Changes in students' self-reported and enacted SRL…

  1. Competencies for Successful Self-Regulated Learning in Higher Education: Structural Model and Indications Drawn from Expert Interviews

    ERIC Educational Resources Information Center

    Dresel, Markus; Schmitz, Bernhard; Schober, Barbara; Spiel, Christine; Ziegler, Albert; Engelschalk, Tobias; Jöstl, Gregor; Klug, Julia; Roth, Anne; Wimmer, Bastian; Steuer, Gabriele

    2015-01-01

    A global characteristic of higher education is the opportunity and necessity for students to self-regulate their learning. In contrast to considerable research focusing on self-regulated learning (SRL) from a behavioural perspective, little is known concerning the underlying competencies which enable students to succeed in SRL. A structural model…

  2. Developing Young Adolescents' Self-Regulation by Means of Formative Assessment: A Theoretical Perspective

    ERIC Educational Resources Information Center

    Meusen-Beekman, Kelly D.; Joosten-ten Brinke, Desirée; Boshuizen, Henny P. A.

    2015-01-01

    Fostering self-regulated learning (SRL) has become increasingly important at various educational levels. Most studies on SRL have been conducted in higher education. The present literature study aims toward understanding self-regulation processes of students in primary and secondary education. We explored the development of young students'…

  3. Using Formative Assessment and Metacognition to Improve Student Achievement

    ERIC Educational Resources Information Center

    Hudesman, John; Crosby, Sara; Flugman, Bert; Issac, Sharlene; Everson, Howard; Clay, Dorie B.

    2013-01-01

    This paper describes a multistep Enhanced Formative Assessment Program (EFAP) that features a Self-Regulated Learning (SRL) component. The program, which teaches students to become more effective learners, has been applied in a wide range of academic disciplines. In this paper we report on how the EFAP-SRL model can be applied to the area of…

  4. The Role of Self-Regulated Learning in Fostering Students' Conceptual Understanding of Complex Systems with Hypermedia

    ERIC Educational Resources Information Center

    Azevedo, Roger; Guthrie, John T.; Seibert, Diane

    2004-01-01

    This study examines the role of self-regulated learning (SRL) in facilitating students' shifts to more sophisticated mental models of the circulatory system as indicated by both performance and process data. We began with Winne and colleagues' information processing model of SRL (Winne, 2001; Winne & Hadwin, 1998) and used it to examine how…

  5. Why Is Externally-Facilitated Regulated Learning More Effective than Self-Regulated Learning with Hypermedia?

    ERIC Educational Resources Information Center

    Azevedo, Roger; Moos, Daniel C.; Greene, Jeffrey A.; Winters, Fielding I.; Cromley, Jennifer G.

    2008-01-01

    We examined how self-regulated learning (SRL) and externally-facilitated self-regulated learning (ERL) differentially affected adolescents' learning about the circulatory system while using hypermedia. A total of 128 middle-school and high school students with little prior knowledge of the topic were randomly assigned to either the SRL or ERL…

  6. Does Training on Self-Regulated Learning Facilitate Students' Learning with Hypermedia?

    ERIC Educational Resources Information Center

    Azevedo, Roger; Cromley, Jennifer G.

    2004-01-01

    The authors examined the effectiveness of self-regulated learning (SRL) training in facilitating college students' learning with hypermedia. Undergraduate students (N = 131) were randomly assigned to either a training condition or a control condition and used a hypermedia environment to learn about the circulatory system. Students in the SRL group…

  7. An Investigation of the Role of Contingent Metacognitive Behavior in Self-Regulated Learning

    ERIC Educational Resources Information Center

    Binbasaran Tuysuzoglu, Banu; Greene, Jeffrey Alan

    2015-01-01

    Studies have shown that, to achieve a conceptual understanding of complex science topics, learners need to use self-regulated learning (SRL) skills, particularly when learning with Hypermedia Learning Environments (HLEs). Winne and Hadwin (2008) claimed that metacognition is a key aspect of SRL, particularly metacognitive monitoring and control.…

  8. Analysis of Self-Regulated Learning Processing Using Statistical Models for Count Data

    ERIC Educational Resources Information Center

    Greene, Jeffrey Alan; Costa, Lara-Jeane; Dellinger, Kristin

    2011-01-01

    Researchers often use measures of the frequency of self-regulated learning (SRL; Zimmerman, "American Educational Research Journal," 45(1), 166-183, 2000) processing as a predictor of learning gains. These frequency data, which are really counts of SRL processing events, are often non-normally distributed, and the accurate analysis of these data…

  9. Adolescents' Use of Self-Regulatory Processes and Their Relation to Qualitative Mental Model Shifts while Using Hypermedia

    ERIC Educational Resources Information Center

    Greene, Jeffrey Alan; Azevedo, Roger

    2007-01-01

    This study examined 148 adolescents' use of self-regulated learning (SRL) processes when learning about the circulatory system using hypermedia. We examined participants' verbal protocols to determine the relationship between SRL processes and qualitative shifts in students' mental models from pretest to posttest. Results indicated that…

  10. Self-Regulated Learning: Studying the Effects of a Nontraditional Instructional Method in the High School Science Classroom

    ERIC Educational Resources Information Center

    Corsi, Gianluca

    2010-01-01

    Self-regulated learning (SRL) encourages students to learn using metacognition, strategic action, and motivation. This nontraditional approach to education relies on the student's active role in learning and the instructor's facilitatory role in teaching. This article provides a comprehensive analysis of an SRL instructional model the author…

  11. Can Students Collaboratively Use Hypermedia to Learn Science? The Dynamics of Self-And Other-Regulatory Processes in an Ecology Classroom

    ERIC Educational Resources Information Center

    Azevedo, Roger; Winters, Fielding I.; Moos, Daniel C.

    2004-01-01

    This classroom study examined the role of low-achieving students' self-regulated learning (SRL) behaviors and their teacher's scaffolding of SRL while using a Web-based water quality simulation environment to learn about ecological systems. Forty-nine 11th and 12th grade students learned about ecology and the effects of land use on water quality…

  12. The Nature of Student Teachers' Regulation of Learning in Teacher Education

    ERIC Educational Resources Information Center

    Endedijk, Maaike D.; Vermunt, Jan D.; Verloop, Nico; Brekelmans, Mieke

    2012-01-01

    Background: Self-regulated learning (SRL) has mainly been conceptualized to involve student learning within academic settings. In teacher education, where learning from theory and practice is combined, student teachers also need to regulate their learning. Hence, there is an urgent need to extend SRL theories to the domain of teacher learning and…

  13. Investigating Postsecondary Self-Regulated Learning Instructional Practices: The Development of the Self-Regulated Learning Observation Protocol

    ERIC Educational Resources Information Center

    Hoops, Leah D.; Yu, Shirley L.; Wang, Qianqian; Hollyer, Virginia L.

    2016-01-01

    Promoting students' self-regulated learning (SRL) is one way to improve postsecondary student success. However, few studies have investigated the instructional practices of postsecondary instructors that may support students' SRL. This study sought to fill this gap. An undergraduate mathematics course was observed to determine instruction utilized…

  14. Emotions and Emotion Regulation in Undergraduate Studying: Examining Students' Reports from a Self-Regulated Learning Perspective

    ERIC Educational Resources Information Center

    Webster, Elizabeth A.; Hadwin, Allyson F.

    2015-01-01

    This study examined undergraduate students' reports of emotions and emotion regulation during studying from a self-regulated learning (SRL) perspective. Participants were 111 university students enrolled in a first-year course designed to teach skills in SRL. Students reflected on their emotional experiences during goal-directed studying episodes…

  15. Students' Self-Regulated Learning, Online Information Evaluative Standards and Online Academic Searching Strategies

    ERIC Educational Resources Information Center

    Tseng, Sheng-Chau; Liang, Jyh-Chong; Tsai, Chin-Chung

    2014-01-01

    Online information searching strategies (OISS) used by students can be viewed as a key indicator in online learning environments. Therefore, developments in their OISS may also involve variables such as self-regulated learning (SRL) and online information evaluative standards (OIES). Three instruments, an OISS, a SRL and an OIES were used to…

  16. Sclerotium rolfsii lectin induces stronger inhibition of proliferation in human breast cancer cells than normal human mammary epithelial cells by induction of cell apoptosis.

    PubMed

    Savanur, Mohammed Azharuddin; Eligar, Sachin M; Pujari, Radha; Chen, Chen; Mahajan, Pravin; Borges, Anita; Shastry, Padma; Ingle, Arvind; Kalraiya, Rajiv D; Swamy, Bale M; Rhodes, Jonathan M; Yu, Lu-Gang; Inamdar, Shashikala R

    2014-01-01

    Sclerotium rolfsii lectin (SRL) isolated from the phytopathogenic fungus Sclerotium rolfsii has exquisite binding specificity towards O-linked, Thomsen-Freidenreich (Galβ1-3GalNAcα1-Ser/Thr, TF) associated glycans. This study investigated the influence of SRL on proliferation of human breast cancer cells (MCF-7 and ZR-75), non-tumorigenic breast epithelial cells (MCF-10A) and normal mammary epithelial cells (HMECs). SRL caused marked, dose-dependent, inhibition of proliferation of MCF-7 and ZR-75 cells but only weak inhibition of proliferation of non-tumorigenic MCF-10A and HMEC cells. The inhibitory effect of SRL on cancer cell proliferation was shown to be a consequence of SRL cell surface binding and subsequent induction of cellular apoptosis, an effect that was largely prevented by the presence of inhibitors against caspases -3, -8, or -9. Lectin histochemistry using biotin-labelled SRL showed little binding of SRL to normal human breast tissue but intense binding to cancerous tissues. In conclusion, SRL inhibits the growth of human breast cancer cells via induction of cell apoptosis but has substantially less effect on normal epithelial cells. As a lectin that binds specifically to a cancer-associated glycan, has potential to be developed as an anti-cancer agent.

  17. Content Analysis of 1998-2012 Empirical Studies in Science Reading Using a Self-Regulated Learning Lens

    ERIC Educational Resources Information Center

    Hsu, Ying-Shao; Yen, Miao-Hsuan; Chang, Wen-Hua; Wang, Chia-Yu; Chen, Sufen

    2016-01-01

    There is an increasing interest in conducting reading-related studies in science education using a self-regulated learning (SRL) lens. This exploration involved a content analysis of 34 articles (38 studies in total) in highly regarded journals from 1998 to 2012 using an SRL interpretative framework to reveal critical features and relationships in…

  18. A Questionnaire-Based Validation of Multidimensional Models of Self-Regulated Learning Strategies

    ERIC Educational Resources Information Center

    Teng, Lin Sophie; Zhang, Lawrence Jun

    2016-01-01

    This study aimed to validate a newly-developed instrument, The Writing Strategies for Self-Regulated Learning (SRL) Questionnaire, with respect to its multifaceted structure of SRL strategies in English as a foreign language (EFL) writing. A total of 790 undergraduate students from 6 universities in Northeast China volunteered to be participants.…

  19. Don't forget the learner: an essential aspect for developing effective hypermedia online learning in continuing medical education.

    PubMed

    Sandars, John; Homer, Matthew; Walsh, Kieran; Rutherford, Alaster

    2012-03-01

    There is increasing use of hypermedia online learning in continuing medical education (CME) that presents the learner with a wide range of different learning resources, requiring the learner to use self-regulated learning (SRL) skills. This study is the first to apply an SRL perspective to understand how learners engage with hypermedia online learning in CME. We found that the main SRL skills used by learners were use of strategies and monitoring. The increasing use of strategies was associated with increasing interest in the topic and with increasing satisfaction with the learning experience. Further research is recommended to understand SRL processes and its impact on learning in other aspects of hypermedia online learning across the different phases of medical education. Research is also recommended to implement and evaluate the learning impact of a variety of approaches to develop the SRL skills of hypermedia online learners in CME.

  20. Effect of solvent on drug release and a spray-coated matrix of a sirolimus-eluting stent coated with poly(lactic-co-glycolic acid).

    PubMed

    Choi, Jiyeon; Jang, Bu Nam; Park, Bang Ju; Joung, Yoon Ki; Han, Dong Keun

    2014-08-26

    Sirolimus (SRL) release from the biodegradable poly(l-lactic-co-glycolic acid) (PLGA) matrix was investigated for the application of drug-eluting stents (DES). In particular, this study focused on whether various organic solvents affect the interaction between SRL and PLGA and the formation of microstructures during ultrasonic coating. The SRL-loaded PLGA coated by tetrahydrofuran or acetone showed a significant initial burst, whereas that from acetonitrile was constantly released during a period of 21 days. On the basis of these results, the interactions at the molecular level of SRL with the polymer matrix were estimated according to various organic solvents. Although the topographies of the coated surface were obviously different, the correlation between surface roughness and SRL release was very poor. Irrespective of organic solvents, FT-IR data showed significantly weak SRL-PLGA interactions. From the result of wide-angle X-ray diffraction, it was confirmed that SRL was dispersed in an amorphous state in the polymer matrix after ultrasonic coating. The glass-transition temperature was also influenced by organic solvents, resulting in a plasticizing effect. The particle size of SRL appeared to determine the release profile from the PLGA matrix, which was the combination of diffusion and polymer degradation at an SRL size of more than 800 nm and the Fickian release at that of less than 300 nm. Therefore, organic solvents can lead to a heterogeneous microstructure in the SRL-loaded PLGA matrix, which is at or near the surface, consisting of aggregated drug- and polymer-rich regions. It is expected that the drug release can be controlled by physicochemical properties of organic solvents, and this study can be used effectively for localized drug release in biomedical devices such as drug-eluting stents.

  1. Efficacy and safety of early tacrolimus conversion to sirolimus after kidney transplantation: Long-term results of a prospective randomized study

    PubMed Central

    El-Agroudy, A. E.; Alarrayed, S. M.; Al-Ghareeb, S. M.; Farid, E.; Alhelow, H.; Abdulla, S.

    2017-01-01

    We report a prospective, open-label, randomized study to evaluate the safety and efficacy of converting patients with a stable renal function from tacrolimus (Tac)-based regimen to a sirolimus (SRL)-based regimen after kidney transplantation. Fifty-eight low-risk renal allograft recipients who receiving Tac 6 months posttransplant, were randomly assigned to continue Tac (n = 29) or convert to SRL (n = 29). We evaluated the 3-year outcomes including patient and graft survival, graft function, and safety profile. Three-year patient and graft survival in SRL and Tac groups were 93.1% versus 100% (P = 0.32), and 89.7% versus 100% (P = 0.11), respectively. However, the SRL group had a significantly better renal function, from the 2nd year posttransplant until the last follow-up. Four (13.8%) patients in the SRL group and 3 (10.3%) in the Tac group (P = 0.5) developed biopsy-proven acute rejection. Mean urinary protein excretion increased significantly after SRL conversion. Diastolic blood pressure was significantly lower at the end of the study in patients who eliminated Tac (80.4 vs. 75.6 mmHg in Tac and SRL group, respectively) (P = 0.03). Mean hemoglobin concentrations decreased after SRL conversion and remained significantly lower from 12 months to 36 months (P = 0.01). The mean serum cholesterol (540 ± 44 mg/dl) and triglyceride (177 ± 27 mg/dl) increased significantly in the SRL group, compared to Tac group (487 ± 62 mg/dl) (P = 0.03) and (141 ± 26 mg/dl) (P = 0.04). Our experience demonstrates that conversion to SRL from calcineurin inhibitors-based therapy may result in better renal function and blood pressure control in renal transplant recipients without an increased risk of acute rejection. However, these benefits have not resulted in a growing advantage in graft or patient survival. PMID:28182044

  2. Short sirolimus half-life in pediatric renal transplant recipients on a calcineurin inhibitor-free protocol

    PubMed Central

    Schachter, A. D.; Meyers, K. E.; Spaneas, L. D.; Palmer, J. A.; Salmanullah, M.; Baluarte, J.; Brayman, K. L.; Harmon, W. E.

    2005-01-01

    Immunosuppression with SRL may provide an opportunity to avoid long-term exposure to the nephrotoxicity of CNI. Thus, we have initiated an experimental protocol of IL-2r antibody induction , prednisone, MMF and SRL in pediatric renal transplant recipients (median age 15.5 yr, IQR 8.5, range 1.3–21.7). The recipients were treated with daclizumab every2 wk for the first 2 months, prednisone on a tapering schedule, MMF at 1200 mg/m2/dayand SRL given b.i.d. The SRL was dosed to achieve defined target whole blood 12-h trough levels. We performed 24 SRL PK profiles in 13 stable pediatric renal transplant recipients at 1 and 3 months post-transplant. Half-life (T1/2) and terminal T1/2 were 9.7 (7.1–24.6) and 10.8 (4.4–95.2) hours (median, range) respectively at month 1, and were 9.6 (5–17.8) and 12.1 (4.7–71.0) hours respectively at month 3. SRL trough levels correlated with AUC (r2 = 0.84, p < 0.001). There was no relationship between SRL and 2 mycophenolic acid (MPA) AUC values (r2 = 0.04). During the first 3 months post-transplant only one patient experienced severe neutropenia and another patient had subclinical (histologic) evidence of a mild acute rejection episode with no change in renal function. We conclude that the T1/2 of SRL in pediatric renal transplant recipients not treated with CNI is much shorter than what has been reported for adults, due to rapid metabolism. We conclude that children require SRL dosing every12 h, higher doses and frequent drug monitoring to achieve target SRL concentrations. PMID:15049798

  3. Short sirolimus half-life in pediatric renal transplant recipients on a calcineurin inhibitor-free protocol.

    PubMed

    Schachter, Asher D; Meyers, K E; Spaneas, L D; Palmer, J A; Salmanullah, M; Baluarte, J; Brayman, K L; Harmon, W E

    2004-04-01

    Immunosuppression with SRL may provide an opportunity to avoid long-term exposure to the nephrotoxicity of CNI. Thus, we have initiated an experimental protocol of IL-2r antibody induction, prednisone, MMF and SRL in pediatric renal transplant recipients (median age 15.5 yr, IQR 8.5, range 1.3-21.7). The recipients were treated with daclizumab every 2 wk for the first 2 months, prednisone on a tapering schedule, MMF at 1200 mg/m(2)/day and SRL given b.i.d. The SRL was dosed to achieve defined target whole blood 12-h trough levels. We performed 24 SRL PK profiles in 13 stable pediatric renal transplant recipients at 1 and 3 months post-transplant. Half-life (T(1/2)) and terminal T(1/2) were 9.7 (7.1-24.6) and 10.8 (4.4-95.2) hours (median, range) respectively at month 1, and were 9.6 (5-17.8) and 12.1 (4.7-71.0) hours respectively at month 3. SRL trough levels correlated with AUC (r(2) = 0.84, p < 0.001). There was no relationship between SRL and mycophenolic acid (MPA) AUC values (r(2) = 0.04). During the first 3 months post-transplant only one patient experienced severe neutropenia and another patient had subclinical (histologic) evidence of a mild acute rejection episode with no change in renal function. We conclude that the T(1/2) of SRL in pediatric renal transplant recipients not treated with CNI is much shorter than what has been reported for adults, due to rapid metabolism. We conclude that children require SRL dosing every 12 h, higher doses and frequent drug monitoring to achieve target SRL concentrations.

  4. Sirolimus reduces the incidence and progression of UVB-induced skin cancer in SKH mice even with co-administration of cyclosporine A.

    PubMed

    Wulff, Brian C; Kusewitt, Donna F; VanBuskirk, Anne M; Thomas-Ahner, Jennifer M; Duncan, F Jason; Oberyszyn, Tatiana M

    2008-10-01

    Transplant immunosuppressants have been implicated in the increased incidence of non-melanoma skin cancer in transplant recipients, most of whom harbor considerable UVB-induced DNA damage in their skin prior to transplantation. This study was designed to evaluate the effects of two commonly used immunosuppressive drugs, cyclosporine A (CsA) and sirolimus (SRL), on the development and progression of UVB-induced non-melanoma skin cancer. SKH-1 hairless mice were exposed to UVB alone for 15 weeks, and then were treated with CsA, SRL, or CsA+SRL for 9 weeks following cessation of UVB treatment. Compared with vehicle, CsA treatment resulted in enhanced tumor size and progression. In contrast, mice treated with SRL or CsA+SRL had decreased tumor multiplicity, size, and progression compared with vehicle-treated mice. CsA, but not SRL or combined treatment, increased dermal mast cell numbers and TGF-beta1 levels in the skin. These findings demonstrate that specific immunosuppressive agents differentially alter the cutaneous tumor microenvironment, which in turn may contribute to enhanced development of UVB-induced skin cancer in transplant recipients. Furthermore, these results suggest that CsA alone causes enhanced growth and progression of skin cancer, whereas co-administration of SRL with CsA causes the opposite effect. JID JOURNAL CLUB ARTICLE: For questions, answers, and open discussion about this article please go to http://network.nature.com/group/jidclub

  5. mTOR Inhibition: Reduced Insulin Secretion and Sensitivity in a Rat Model of Metabolic Syndrome

    PubMed Central

    Rovira, Jordi; Ramírez-Bajo, María Jose; Banon-Maneus, Elisenda; Moya-Rull, Daniel; Ventura-Aguiar, Pedro; Hierro-Garcia, Natalia; Lazo-Rodriguez, Marta; Revuelta, Ignacio; Torres, Armando; Oppenheimer, Federico; Campistol, Josep M.; Diekmann, Fritz

    2016-01-01

    Background Sirolimus (SRL) has been associated with new-onset diabetes mellitus after transplantation. The aim was to determine the effect of SRL on development of insulin resistance and β-cell toxicity. Methods Lean Zucker rat (LZR) and obese Zucker rat (OZR) were distributed into groups: vehicle and SRL (0.25, 0.5, or 1.0 mg/kg) during 12 or 28 days. Intraperitoneal glucose tolerance test (IPGTT) was evaluated at days 0, 12, 28, and 45. Islet morphometry, β-cell proliferation, and apoptosis were analyzed at 12 days. Islets were isolated to analyze insulin content, insulin secretion, and gene expression. Results After 12 days, SRL treatment only impaired IPGTT in a dose-dependent manner in OZR. Treatment prolongation induced increase of area under the curve of IPGTT in LZR and OZR; however, in contrast to OZR, LZR normalized glucose levels after 2 hours. The SRL reduced pancreas weight and islet proliferation in LZR and OZR as well as insulin content. Insulin secretion was only affected in OZR. Islets from OZR + SRL rats presented a downregulation of Neurod1, Pax4, and Ins2 gene. Genes related with insulin secretion remained unchanged or upregulated. Conclusions In conditions that require adaptive β-cell proliferation, SRL might reveal harmful effects by blocking β-cell proliferation, insulin production and secretion. These effects disappeared when removing the therapy. PMID:27500257

  6. Integrating Skills and Wills Instruction in Self-Regulated Science Text Reading for Secondary Students

    NASA Astrophysics Data System (ADS)

    Michalsky, Tova

    2013-07-01

    This study investigated the effectiveness of cognitive-metacognitive versus motivational components of the IMPROVE self-regulatory model, used while reading scientific texts, for 10th graders' scientific literacy and self-regulated learning (SRL). Three treatment groups (N = 198) received one type of self-addressable questions while reading scientific texts: cognitive-metacognitive (CogMet), motivational (Mot), or combined (CogMetMot). Control group received no self-addressed questions (noSRL). One measure assessed scientific literacy, and two measures assessed SRL: (a) as an aptitude-pre/post questionnaires assessing self-perceived SRL, and (b) as an event-audiotaping participants' thinking-aloud SRL behaviors in real-time learning experiences and data coding illustrating SRL changes. Findings indicated that treatment groups significantly outperformed the non-treatment group. No differences emerged between CogMet and Mot, whereas fully combined SRL support (CogMetMot) was most effective. Theoretical and practical implications of this preliminary study are discussed.

  7. Comparable Renal Function at 6 Months with Tacrolimus Combined with Fixed-Dose Sirolimus or MMF: Results of a Randomized Multicenter Trial in Renal Transplantation.

    PubMed

    Van Gurp, Eveline; Bustamante, Jesus; Franco, Antonio; Rostaing, Lionel; Becker, Thomas; Rondeau, Eric; Czajkowski, Zenon; Rydzewski, Andrzej; Alarcon, Antonio; Bachleda, Petr; Samlik, Jiri; Burmeister, Dirk; Pallardo, Luis; Moal, Marie-Christine; Rutkowski, Boleslaw; Wlodarczyk, Zbigniew

    2010-01-01

    In a multicenter trial, renal transplant recipients were randomized to tacrolimus with fixed-dose sirolimus (Tac/SRL, N = 318) or tacrolimus with MMF (Tac/MMF, N = 316). Targeted tacrolimus trough levels were lower in the Tac/SRL group after day 14. The primary endpoint was renal function at 6 months using creatinine clearance (Cockcroft-Gault) and was comparable at 66.4 mL/min (SE 1.4) with Tac/SRL and at 65.2mL/min (SE 1.3) with Tac/MMF (completers). Biopsy-confirmed acute rejection was 15.1% (Tac/SRL) and 12.3% (Tac/MMF). In both groups, graft survival was 93% and patient survival was 99.0%. Premature withdrawal due to an adverse event was twice as high in the Tac/SRL group, 15.1% versus 6.3%. Hypercholesterolemia incidence was higher with Tac/SRL (P < .05) while CMV, leukopenia, and diarrhea incidences were higher with Tac/MMF (P < .05). The incidence of any antidiabetic treatment for >30 consecutive days in previously nondiabetic patients was 17.8%, Tac/SRL, and 24.8%, Tac/MMF. Evaluation at 6 months showed comparable renal function using tacrolimus/sirolimus and tacrolimus/MMF regimens.

  8. Sirolimus and Everolimus Pathway: Reviewing Candidate Genes Influencing Their Intracellular Effects

    PubMed Central

    Granata, Simona; Dalla Gassa, Alessandra; Carraro, Amedeo; Brunelli, Matteo; Stallone, Giovanni; Lupo, Antonio; Zaza, Gianluigi

    2016-01-01

    Sirolimus (SRL) and everolimus (EVR) are mammalian targets of rapamycin inhibitors (mTOR-I) largely employed in renal transplantation and oncology as immunosuppressive/antiproliferative agents. SRL was the first mTOR-I produced by the bacterium Streptomyces hygroscopicus and approved for several medical purposes. EVR, derived from SRL, contains a 2-hydroxy-ethyl chain in the 40th position that makes the drug more hydrophilic than SRL and increases oral bioavailability. Their main mechanism of action is the inhibition of the mTOR complex 1 and the regulation of factors involved in a several crucial cellular functions including: protein synthesis, regulation of angiogenesis, lipid biosynthesis, mitochondrial biogenesis and function, cell cycle, and autophagy. Most of the proteins/enzymes belonging to the aforementioned biological processes are encoded by numerous and tightly regulated genes. However, at the moment, the polygenic influence on SRL/EVR cellular effects is still not completely defined, and its comprehension represents a key challenge for researchers. Therefore, to obtain a complete picture of the cellular network connected to SRL/EVR, we decided to review major evidences available in the literature regarding the genetic influence on mTOR-I biology/pharmacology and to build, for the first time, a useful and specific “SRL/EVR genes-focused pathway”, possibly employable as a starting point for future in-depth research projects. PMID:27187382

  9. Domain adaptation for semantic role labeling of clinical text

    PubMed Central

    Zhang, Yaoyun; Tang, Buzhou; Jiang, Min; Wang, Jingqi

    2015-01-01

    Objective Semantic role labeling (SRL), which extracts a shallow semantic relation representation from different surface textual forms of free text sentences, is important for understanding natural language. Few studies in SRL have been conducted in the medical domain, primarily due to lack of annotated clinical SRL corpora, which are time-consuming and costly to build. The goal of this study is to investigate domain adaptation techniques for clinical SRL leveraging resources built from newswire and biomedical literature to improve performance and save annotation costs. Materials and Methods Multisource Integrated Platform for Answering Clinical Questions (MiPACQ), a manually annotated SRL clinical corpus, was used as the target domain dataset. PropBank and NomBank from newswire and BioProp from biomedical literature were used as source domain datasets. Three state-of-the-art domain adaptation algorithms were employed: instance pruning, transfer self-training, and feature augmentation. The SRL performance using different domain adaptation algorithms was evaluated by using 10-fold cross-validation on the MiPACQ corpus. Learning curves for the different methods were generated to assess the effect of sample size. Results and Conclusion When all three source domain corpora were used, the feature augmentation algorithm achieved statistically significant higher F-measure (83.18%), compared to the baseline with MiPACQ dataset alone (F-measure, 81.53%), indicating that domain adaptation algorithms may improve SRL performance on clinical text. To achieve a comparable performance to the baseline method that used 90% of MiPACQ training samples, the feature augmentation algorithm required <50% of training samples in MiPACQ, demonstrating that annotation costs of clinical SRL can be reduced significantly by leveraging existing SRL resources from other domains. PMID:26063745

  10. NASA/GSFC Scanning Raman Lidar Measurements of Water Vapor and Clouds During IHOP

    NASA Technical Reports Server (NTRS)

    Whiteman, David N.; Demoz, Belay; DiGirolamo, Paolo; Comer, Joe; Wang, Zhien; Lin, Rei-Fong; Evans, Keith; Veselovskii, Igor

    2004-01-01

    The NASA/GSFC Scanning Raman Lidar (SRL) participated in the International H2O Project (IHOP) that occurred in May and June, 2002 in the midwestern part of the U.S. The SRL acquired measurements of water vapor, aerosols, cloud liquid and ice water, and temperature for more than 200 hours during IHOP. Here we report on the SRL water vapor and cirrus cloud measurements with particular emphasis being given to the measurements of June 19-20, 2002, which are motivating cirrus cloud model comparison studies.

  11. Health protection well inventory

    SciTech Connect

    Janssen, J.

    1989-03-01

    This report is an inventory of the wells contained in Health Protection (HP) documents since the startup of the Savannah River Plan (SRP) and includes wells monitored by special request and SRL research wells.

  12. Scanning Raman Lidar Measurements During the WVIOP2000 and AFWEX Field Experiments

    NASA Technical Reports Server (NTRS)

    Whiteman, David N.; Evans, K. D.; Berkoff, T. B.; Demoz, B. D.; DiGirolamo, P.; Smith, David E. (Technical Monitor)

    2001-01-01

    The NASA/Goddard Space Flight Center Scanning Raman Lidar (SRL) participated in the Water Vapor IOP 2000 (WVIOP2000) and ARM FIRE Water Vapor Experiment (AFWEX) at the DOE SGP CART site in northern Oklahoma. These experiments occurred during the period of September and December, 2000. The goals of both the WVIOP2000 and AFWEX were to better characterize the water vapor measurement capability of numerous sensors in the lower atmosphere and upper troposphere, respectively. The SRL received several hardware upgrades in anticipation of these experiments that permitted improved measurements of water vapor during the daytime and in the upper troposphere (UT). The daytime SRL water vapor error statistics were demonstrated a factor of 2-3 improvement compared to the permanently stationed CART Raman lidar (CARL). The performance of the SRL in the UT showed improvements as well. The technological upgrades that permitted these improved SRL measurements could also be implemented in the CARL system. Data examples demonstrating the new daytime and upper tropospheric measurement capability of the SRL will be shown at the meeting. In addition, preliminary analysis will be presented on several topics: 1) inter comparison of the water vapor measurements for several water vapor sensors including SRL, CARL, the NASA/Langley Lidar Atmospheric Sensing Experiment (LASE) flown onboard the NASA DC-8, in-situ sensors flown on the DC-8, and the Max Planck Institute Differential Absorption Lidar 2) comparison of cirrus cloud measurements using SRL and CARL and 3) case studies of meteorological events that occurred during the IOPs such as a cold frontal passage on the night of September 23.

  13. Advanced Infrared Photodetectors (Materials Review)

    DTIC Science & Technology

    1993-12-01

    rays by reducing the effective detector area (9]. The lens structure also offers a measure of mechanical protection. 2.3.2 Electronic non...ib.itio’ý I by Availability Codes Philip J. Picone Avail and/ornDist Special SUMMARY The present status of advanced infrared semiconductor detector materials... POSTAL ADDRESS: Director, Surveillance Research Laboratory, PO Box 1500, Salisbury, South Australia, 5108. SRL.0117-RR UNCLASSIFIED SRL - 0117 - RR

  14. Final design review of boron carbide safety rod

    SciTech Connect

    Lutz, R.N.

    1991-09-24

    The object of this paper discusses the design review of the boron carbide safety rod for the Westinghouse Savannah River Company. This paper reviewed information presented by personnel of the Savannah River Laboratory (SRL) Equipment Engineering Section, SRL Materials Technology Section and Reactor Materials Engineering and Technology. From this report, views, opinions and recommendations were made on the safety rod from materials testing to production.

  15. IMMUNOSUPPRESSANT NEUROTOXICITY IN RAT BRAIN MODELS: OXIDATIVE STRESS AND CELLULAR METABOLISM

    PubMed Central

    Klawitter, Jelena; Gottschalk, Sven; Hainz, Carsten; Leibfritz, Dieter; Christians, Uwe; Serkova, Natalie J.

    2010-01-01

    Co-administration of the calcineurin inhibitor cyclosporine (CsA) and the mTOR inhibitors sirolimus (SRL) or everolimus (RAD) increases efficacy of immunosuppression after organ transplantation. Neurotoxicity of CsA is a major clinical problem. Our goal was to assess the effects of CsA, SRL and RAD on the brain cell metabolism. The studies included the comparison of immunosuppressant-mediated effects on glucose metabolism, energy production and reactive oxygen species (ROS) formation in perfused rat brain slices, primary rat astrocytes and C6-glioma cells. In brain slices and astrocytes, CsA inhibited Krebs cycle metabolism, while activating anaerobic glycolysis most likely to compensate for the inhibition of mitochondrial energy production. SRL and RAD inhibited cytosolic glycolysis, but did not cause changes in mitochondrial energy production. CsA+SRL inhibited Krebs cycle and glycolysis, thus reducing the ability of the cell to compensate for the negative effects of CsA on mitochondrial nucleoside triphosphate synthesis. In contrast to SRL at the concentrations tested, RAD reduced the CsA-induced ROS formation and antagonized CsA-induced effects on glucose and energy metabolism. Surprisingly, in C6 cells, SRL and RAD exposure resulted in high ROS concentrations without significant impairment of cell metabolism. Our results suggested that SRL enhances CsA-induced ROS formation and negative metabolic effects in brain cells, while RAD seems to antagonize the CsA effects. However, the three models showed different metabolic responses when challenged with the study drugs. In contrast to SRL, RAD enhances ROS formation in C6 glioma cells, but has only minor effects on normal rat brain tissue. PMID:20148532

  16. Multi-Objective Optimization of System Capability Satisficing in Defense Acquisition

    DTIC Science & Technology

    2012-04-30

    MVCS (USV) MVCS (RMMV) TSCE MH-60 MPS...Combat Mgmt System MVCS (On-board) MPCE MP SRL MP SRL w/o Sea Frame MP 1 0.60 0.57 USV; MPCE; RMMV; MVCS (USV); BPAUV PC MH-60S 7 7 6...3 6 MH-60S; MH-60S MPS MVCS (OB) MVCS (RMMV) US3; BPAUV AQS-20 AMNS; ALMDS Trade Between Advanced Capability or Increased Maturity

  17. FERMI: A Flexible Expert Reasoner with Multi-Domain Inferencing.

    DTIC Science & Technology

    2014-09-26

    representation systems. In particular, FERMI uses schemas, (Brachman, 1979, Minsky, 1975, 1975, Fox , 1979, Bobrow, 1977)data structures composed of...if-added demons in the CONNIVER system (Sussman, 1975), and continuing through KAL (Bobrow, 1977) and SRL (Wright & Fox , 1983, 1983). FERMI’s schemas...language SRL ( Fox , 1979, Wright & Fox , 1983, 1983) in which isa links cause automatic inheritance of all the slots and their associated knowledge

  18. Over-Expression of 60s Ribosomal L23a Is Associated with Cellular Proliferation in SAG Resistant Clinical Isolates of Leishmania donovani

    PubMed Central

    Das, Sanchita; Shah, Priyanka; Baharia, Rajendra K.; Tandon, Rati; Khare, Prashant; Sundar, Shyam; Sahasrabuddhe, Amogh A.; Siddiqi, M. I.; Dube, Anuradha

    2013-01-01

    Background Sodium antimony gluconate (SAG) unresponsiveness of Leishmania donovani (Ld) had effectively compromised the chemotherapeutic potential of SAG. 60s ribosomal L23a (60sRL23a), identified as one of the over-expressed protein in different resistant strains of L.donovani as observed with differential proteomics studies indicates towards its possible involvement in SAG resistance in L.donovani. In the present study 60sRL23a has been characterized for its probable association with SAG resistance mechanism. Methodology and principal findings The expression profile of 60s ribosomal L23a (60sRL23a) was checked in different SAG resistant as well as sensitive strains of L.donovani clinical isolates by real-time PCR and western blotting and was found to be up-regulated in resistant strains. Ld60sRL23a was cloned, expressed in E.coli system and purified for raising antibody in swiss mice and was observed to have cytosolic localization in L.donovani. 60sRL23a was further over-expressed in sensitive strain of L.donovani to check its sensitivity profile against SAG (Sb V and III) and was found to be altered towards the resistant mode. Conclusion/Significance This study reports for the first time that the over expression of 60sRL23a in SAG sensitive parasite decreases the sensitivity of the parasite towards SAG, miltefosine and paramomycin. Growth curve of the tranfectants further indicated the proliferative potential of 60sRL23a assisting the parasite survival and reaffirming the extra ribosomal role of 60sRL23a. The study thus indicates towards the role of the protein in lowering and redistributing the drug pressure by increased proliferation of parasites and warrants further longitudinal study to understand the underlying mechanism. PMID:24340105

  19. [Sirolimus for rescue of recurrent acute rejection and diabetes mellitus after liver transplantation: report of one case].

    PubMed

    Roque, Jorge; Ríos, Gloria; Hepp, Juan; Humeres, Roberto; Ríos, Horacio; Herrera, José M; Rius, Montserrat

    2005-10-01

    Sirolimus (SRL) is a new immunosuppressive drug approved for renal transplantation, but is being used increasingly in orthotopic liver transplantation (OLT). Compared with the calcineurin inhibitors, SRL has different mechanisms of action and side effects profile. Thus, this drug offers significant potential advantages over other immunosuppressive agents. SRL does not cause glucose intolerance, hypertension or renal failure, but it may cause dyslipidemia, hepatic artery thrombosis, thrombocytopenia, anemia, leukopenia, oral mucosa ulcers, edema, arthralgias and wound complications. SRL inhibits the signal of interleukin 2 at a post-receptor level, inhibiting lymphocyte proliferation and fibroblast proliferation. It also has antineoplastic and antifungal effects. We report a 10 years old girl who underwent OLT, experiencing a biopsy-proven recurrent acute rejection (AR) in spite of using three immunosuppressive agents (tacrolimus, mofetil micofenolate and steroids). She developed diabetes mellitus as a consequence of the immunosuppressive therapy. She was rescued with SRL, not experiencing AR again. Mofetil micofenolate, steroids and insulin could be discontinued and tacrolimus doses were reduced, without experiencing severe complications. SRL is a new and safe immunosuppressive agent for rescue in patients with OLT and recurrent AR.

  20. Semi-Rolled Leaf2 modulates rice leaf rolling by regulating abaxial side cell differentiation

    PubMed Central

    Liu, Xiaofei; Li, Ming; Liu, Kai; Tang, Ding; Sun, Mingfa; Li, Yafei; Shen, Yi; Du, Guijie; Cheng, Zhukuan

    2016-01-01

    Moderate leaf rolling maintains the erectness of leaves and minimizes the shadowing between leaves which is helpful to establish ideal plant architecture. Here, we describe a srl2 (semi-rolled leaf2) rice mutant, which has incurved leaves due to the presence of defective sclerenchymatous cells on the abaxial side of the leaf and displays narrow leaves and reduced plant height. Map-based cloning revealed that SRL2 encodes a novel plant-specific protein of unknown biochemical function. SRL2 was mainly expressed in the vascular bundles of leaf blades, leaf sheaths, and roots, especially in their sclerenchymatous cells. The transcriptional activities of several leaf development-related YABBY genes were significantly altered in the srl2 mutant. Double mutant analysis suggested that SRL2 and SHALLOT-LIKE1 (SLL1)/ROLLED LEAF9 (RL9) function in distinct pathways that regulate abaxial-side leaf development. Hence, SRL2 plays an important role in regulating leaf development, particularly during sclerenchymatous cell differentiation. PMID:26873975

  1. GaAsSb/InAs/(In)GaAs type II quantum dots for solar cell applications

    NASA Astrophysics Data System (ADS)

    Vyskočil, Jan; Hospodková, Alice; Petříček, Otto; Pangrác, Jiří; Zíková, Markéta; Oswald, Jiří; Vetushka, Aliaksei

    2017-04-01

    We focused on design of suitable underlying and covering layers of InAs/GaAs quantum dots (QDs) with the aim to increase the carrier extraction rate in the QD solar cell structures. Covering QDs by a GaAsSb strain reducing layer (SRL) with type II band alignment significantly improves photogenerated carrier extraction from InAs QDs. An additional thin InGaAs SRL below InAs QDs further enhances the extraction of photogenerated carriers. Properties of QD structures without any SRL, with GaAsSb covering SRL, and with combination of thin below-QDs InGaAs and GaAsSb covering SRLs are compared and the mechanism of carrier extraction is discussed. We showed that thin below-QDs InGaAs SRL together with increasing profile of antimony concentration in covering GaAsSb SRL can significantly improve the resulting properties of solar cell structures with InAs QDs.

  2. Electrodermal activity during total sleep deprivation and its relationship with other activation and performance measures.

    PubMed

    Miró, E; Cano-Lozano, M C; Buela-Casal, G

    2002-06-01

    The present study analyses the variations of the skin resistance level (SRL) during 48 h of total sleep deprivation (TSD) and its relationship to body temperature, self-informed sleepiness in the Stanford Sleepiness Scale (SSS), and reaction time (RT). All of the variables were evaluated every 2 h except for the SSS, which was evaluated every hour. A total of 30 healthy subjects (15 men and 15 women) from 18 to 24 years old participated in the experiment. Analyses of variance (ANOVAs) with TSD days and time-of-day as factors showed a substantial increase of SRL, SSS, and RT, and a decrease in body temperature marked by strong circadian oscillations. The interaction between day by time-of-day was only significant for RT. Furthermore, Pearson's correlations showed that the increase of SRL is associated to the decrease in temperature (mean r=-0.511), the increase of SSS (mean r=0.509), and the deterioration of RT (mean r=0.425). The results support previous TSD reports and demonstrate the sensitivity of SRL to TSD. The non-invasive character of SRL, its simplicity, and its relationships with other activation parameters, widely validated by previous literature, convert SRL into an interesting and useful measure in this field.

  3. The effects of strength-based versus deficit-based self-regulated learning strategies on students' effort intentions.

    PubMed

    Hiemstra, Djoerd; Van Yperen, Nico W

    In two randomized experiments, one conducted online (n = 174) and one in the classroom (n = 267), we tested the effects of two types of self-regulated learning (SRL) strategies on students' intentions to put effort into professional development activities: strength-based SRL strategies (i.e., identifying perceived relative strengths and, subsequently, selecting professional development activities to further improve those strengths) versus deficit-based SRL strategies (i.e., identifying perceived relative shortcomings and, subsequently, selecting professional development activities to improve those shortcomings). Across both studies, analysis of variance revealed that, relative to students who used deficit-based SRL strategies, students who used strength-based SRL strategies were higher in perceived competence, intrinsic motivation, and effort intentions. Moreover, the results of multi-mediator analysis and structural equation modeling supported the hypothesis that the effect of strength-based versus deficit-based SRL strategies on students' effort intentions was sequentially mediated by perceived competence and intrinsic motivation. Implications for the application of self-regulated learning strategies in the context of professional self-development are discussed.

  4. Evaluation of uranium geochemical anomalies in the Spartanburg 1/sup 0/ x 2/sup 0/ NTMS area near Pacolet Mills, SC

    SciTech Connect

    Owen, J.

    1981-06-01

    The Savannah River Laboratory (SRL) was involved in the National Uranium Resource Evaluation (NURE) program from 1974 through 1981. The SRL role was to design, conduct, and report the data from a geochemical reconnaissance of almost half the continental United States. The purpose of this work was to provide a basis for evaluating the uranium potential of areas and to identify areas meriting conventional geological followup. In this program over 275,000 samples of stream sediment, soil vegetation, and ground or surface water were collected. As a part of the development program to support interpretation of the geochemical data, SRL conducted a series of anomaly verification field studies. Each study area was chosen on the basis of a geochemical anomaly in reconnaissance data. Subcontractors were selected to conduct field scintillometer surveys, compile geologic maps, collect additional samples, or provide other services as deemed appropriate for a given study. This report, which summarizes the results of a study in the Spartanburg 1/sup 0/ x 2/sup 0/ quadrangle, was compiled for SRL by Jerry Owen and is published as a facsimile of this report to SRL. Normal editing was not done so that the report could be placed in the public domain prior to the termination of the NURE program. This study is one of a series designed to provide a basis for interpretation of SRL regional geochemical reconnaissance data. It contains a synthesis of published data and results of a four-channel gamma spectrometer survey of an area near Pacolet Mills, South Carolina.

  5. Response of human renal tubular cells to cyclosporine and sirolimus: A toxicogenomic study

    SciTech Connect

    Pallet, Nicolas Rabant, Marion; Xu-Dubois, Yi-Chun; LeCorre, Delphine; Mucchielli, Marie-Helene; Imbeaud, Sandrine; Agier, Nicolas; Thervet, Eric; Legendre, Christophe; Beaune, Philippe; Anglicheau, Dany

    2008-06-01

    The molecular mechanisms involved in the potentially nephrotoxic response of tubular cells to immunosuppressive drugs remain poorly understood. Transcriptional profiles of human proximal tubular cells exposed to cyclosporine A (CsA), sirolimus (SRL) or their combination, were established using oligonucleotide microarrays. Hierarchical clustering of genes implicated in fibrotic processes showed a clear distinction between expression profiles with CsA and CsA + SRL treatments on the one hand and SRL treatment on the other. Functional analysis found that CsA and CsA + SRL treatments preferentially alter biological processes located at the cell membrane, such as ion transport or signal transduction, whereas SRL modifies biological processes within the nucleus and related to transcriptional activity. Genome wide expression analysis suggested that CsA may induce an endoplasmic reticulum (ER) stress in tubular cells in vitro. Moreover we found that CsA exposure in vivo is associated with the upregulation of the ER stress marker BIP in kidney transplant biopsies. In conclusion, this toxicogenomic study highlights the molecular interaction networks that may contribute to the tubular response to CsA and SRL. These results may also offer a new working hypothesis for future research in the field of CsA nephrotoxicity. Further studies are needed to evaluate if ER stress detection in tubular cells in human biopsies can predict CsA nephrotoxicity.

  6. Long-term renal allograft function on a tacrolimus-based, pred-free maintenance immunosuppression comparing sirolimus vs. MMF.

    PubMed

    Gallon, L; Perico, N; Dimitrov, B D; Winoto, J; Remuzzi, G; Leventhal, J; Gaspari, F; Kaufman, D

    2006-07-01

    It is not known how different steroid-free immunosuppressive combinations affect renal graft survival and long-term kidney transplant function. Here we sought to compare the impact on graft survival and long-term graft function of two tacrolimus (Tac)-based, prednisone-free maintenance immunosuppressive protocols: Tac/Mycophenolate Mofetil (MMF) vs. Tac/Sirolimus (SRL). Renal transplant patients given induction therapy with IL2-RA and methylprednisolone on days 0, 1 and 2 post-transplant were prospectively randomized to two maintenance immunosuppressive regimens with Tac/MMF (n = 45) or Tac/SRL (n = 37). During the 3-year follow-up the following data were collected: patient survival, renal allograft survival, incidence of acute rejection and glomerular filtration rate (GFR) at different time-points post-transplant. Cumulative graft survival was significantly different in the two groups: one kidney loss in the Tac/MMF vs. six kidney losses in the Tac/SRL (log-rank test p = 0.04). GFR at different time-points post-transplant was consistently and statistically better in the Tac/MMF than in the Tac/SRL group. The slope of GFR decline per month was flatter in the Tac/MMF than in the Tac/SRL group. This study showed that renal graft survival and graft function were significantly lower in the combination of Tac/SRL than Tac/MMF.

  7. The role of self-regulated learning in explaining examination performance of college students in first-semester general chemistry

    NASA Astrophysics Data System (ADS)

    Beckley, Scott

    Many college students struggle with first-semester general chemistry. Prior studies have shown that a student's prior knowledge of chemistry, a cognitive factor, does not account for the total variance when measured by examination scores. This study explored the role of self-regulated learning (SRL) to identify the degree of success or failure of students with two outcome variables (i.e., American Chemical Society Comprehensive First-Term General Chemistry Examination (Form 2009) and hour-examination averages). The SRL construct consists of three interrelated components (i.e., cognitive, metacognitive, and motivational). SRL theory focuses on the idea of reciprocal determinism, in which the impact of one component of self-regulation affects the other two components. In the quantitative portion of this mixed methods study, eight measures of SRL were used to determine the `level' of self-regulation for each student. SRL variables were used in regression analysis and provided additional and unique variances. Cluster analysis techniques identified two distinct groups of students (i.e., adaptive and maladaptive). Generally, adaptive learners were associated with higher levels of SRL and success in the course; maladaptive learners had lower levels of SRL and struggled with the course demands. For the qualitative portion of the study, student volunteers (n = 8) were interviewed to gauge their views on the role of instruction in influencing their examination performances. The findings indicated that perceptions of teaching methods, demands of the course, course structure, feedback, and assessments were associated with the students' levels of self-regulation. Interviews revealed four SRL styles. Rote memorizers tended to fragment instruction and then memorize each fragment, while algorithmic memorizers tended to imitate the step-by-step problem-solving strategies of the instructor or the textbook. Globalizers were intrinsically motivated to learn the material but tended to

  8. Modeling and preliminary testing socket-residual limb interface stiffness of above-elbow prostheses.

    PubMed

    Sensinger, Jonathon W; Weir, Richard F ff

    2008-04-01

    The interface between the socket and residual limb can have a significant effect on the performance of a prosthesis. Specifically, knowledge of the rotational stiffness of the socket-residual limb (S-RL) interface is extremely useful in designing new prostheses and evaluating new control paradigms, as well as in comparing existing and new socket technologies. No previous studies, however, have examined the rotational stiffness of S-RL interfaces. To address this problem, a math model is compared to a more complex finite element analysis, to see if the math model sufficiently captures the main effects of S-RL interface rotational stiffness. Both of these models are then compared to preliminary empirical testing, in which a series of X-rays, called fluoroscopy, is taken to obtain the movement of the bone relative to the socket. Force data are simultaneously recorded, and the combination of force and movement data are used to calculate the empirical rotational stiffness of elbow S-RL interface. The empirical rotational stiffness values are then compared to the models, to see if values of Young's modulus obtained in other studies at localized points may be used to determine the global rotational stiffness of the S-RL interface. Findings include agreement between the models and empirical results and the ability of persons to significantly modulate the rotational stiffness of their S-RL interface a little less than one order of magnitude. The floor and ceiling of this range depend significantly on socket length and co-contraction levels, but not on residual limb diameter or bone diameter. Measured trans-humeral S-RL interface rotational stiffness values ranged from 24-140 Nm/rad for the four subjects tested in this study.

  9. Molecular mechanism of anticancer effect of Sclerotium rolfsii lectin in HT29 cells involves differential expression of genes associated with multiple signaling pathways: A microarray analysis.

    PubMed

    Barkeer, Srikanth; Guha, Nilanjan; Hothpet, Vishwanathreddy; Saligrama Adavigowda, Deepak; Hegde, Prajna; Padmanaban, Arunkumar; Yu, Lu-Gang; Swamy, Bale M; Inamdar, Shashikala R

    2015-12-01

    Sclerotium rolfsii lectin (SRL) is a lectin isolated from fungus S. rolfsii and has high binding specificity toward the oncofetal Thomsen-Friedenreich carbohydrate antigen (Galβ1-3GalNAc-α-O-Ser/Thr, T or TF), which is expressed in more than 90% of human cancers. Our previous studies have shown that binding of SRL to human colon, breast and ovarian cancer cells induces cell apoptosis in vitro and suppresses tumor growth in vivo. This study investigated the SRL-mediated cell signaling in human colon cancer HT29 cells by mRNA and miRNA microarrays. It was found that SRL treatment results in altered expression of several hundred molecules including mitogen-activated protein kinase (MAPK) and c-JUN-associated, apoptosis-associated and cell cycle and DNA replication-associated signaling molecules. Pathway analysis using GeneSpring 12.6.1 revealed that SRL treatment induces changes of MAPK and c-JUN-associated signaling pathways as early as 2 h while changes of cell cycle, DNA replication and apoptosis pathways were significantly affected only after 24 h. A significant change of cell miRNA expression was also observed after 12 h treatment of the cells with SRL. These changes were further validated by quantitative real time polymerase chain reaction and immunoblotting. This study thus suggests that the presence of SRL affects multiple signaling pathways in cancer cells with early effects on cell proliferation pathways associated with MAPK and c-JUN, followed by miRNA-associated cell activity and apoptosis. This provides insight information into the molecular mechanism of the anticancer activity of this fungal lectin.

  10. NASA/GSFC Scanning Raman Lidar Measurements of Water Vapor and Cirrus Clouds during WVIOP2000 and AFWEX

    NASA Technical Reports Server (NTRS)

    Whiteman, D. N.; Evans, K. D.; DiGirolamo, P.; Demoz, B. B.; Turner, D.; Comstock, J.; Ismail, S.; Ferrare, R. A.; Browell, E. V.; Goldsmith, J. E. M.; Abshire, James B. (Technical Monitor)

    2002-01-01

    The NASA/GSFC Scanning Raman Lidar (SRL) was deployed to the Southern Great Plains CART site from September - December, 2000 and participated in two field campaigns devoted to comparisons of various water vapor measurement technologies and calibrations. These campaigns were the Water Vapor Intensive Operations Period 2000 (WVIOP2000) and the ARM FIRE Water Vapor Experiment (AFWEX). WVIOP2000 was devoted to validating water vapor measurements in the lower atmosphere while AFWEX had similar goals but for measurements in the upper troposphere. The SRL was significantly upgraded both optically and electronically prior to these field campaigns. These upgrades enabled the SRL to demonstrate the highest resolution lidar measurements of water vapor ever acquired during the nighttime and the highest S/N Raman lidar measurements of water vapor in the daytime; more than a factor of 2 increase in S/N versus the DOE CARL Raman Lidar. Examples of these new measurement capabilities along with comparisons of SRL and CARL, LASE, MPI-DIAL, in-situ sensors, radiosonde, and others will be presented. The profile comparisons of the SRL and CARL have revealed what appears to be an overlap correction or countrate correction problem in CARL. This may be involved in an overall dry bias in the precipitable water calibration of CARL with respect to the MWR of approx. 4%. Preliminary analysis indicates that the application of a temperature dependent correction to the narrowband Raman lidar measurements of water vapor improves the lidar/Vaisala radiosonde comparisons of upper tropospheric water vapor. Other results including the comparison of the first-ever simultaneous measurements from four water vapor lidar systems, a bore-wave event captured at high resolution by the SRL and cirrus cloud optical depth studies using the SRL and CARL will be presented at the meeting.

  11. Efficacy and safety of early cyclosporine conversion to sirolimus with continued MMF-four-year results of the Postconcept study.

    PubMed

    Lebranchu, Y; Thierry, A; Thervet, E; Büchler, M; Etienne, I; Westeel, P F; Hurault de Ligny, B; Moulin, B; Rérolle, J P; Frouget, T; Girardot-Seguin, S; Toupance, O

    2011-08-01

    Calcineurin inhibitor (CNI) withdrawal has been used as a strategy to improve renal allograft function. We previously reported that conversion from cyclosporine A (CsA) to sirolimus (SRL) 3 months after transplantation significantly improved renal function at 1 year. In the Postconcept trial, 77 patients in the SRL group and 85 in the CsA group were followed for 48 months. Renal function (Cockcroft and Gault) was significantly better at month 48 (M48) in the SRL group both in the intent-to-treat population (ITT): 62.6 mL/min/1.73 m(2) versus 57.1 mL/min/1.73 m(2) (p = 0.013) and in the on-treatment population (OT): 67.5 mL/min/1.73 m(2) versus 57.4 mL/min/1.73 m(2) (p = 0.002). Two biopsy proven acute rejection episodes occurred after M12 in each group. Graft and patient survival were comparable (graft survival: 97.4 vs. 100%; patient survival: 97.4 vs. 97.6%, respectively). The incidence of new-onset diabetes was numerically increased in the SRL group (7 vs. 2). In OT, three cancers occurred in the SRL group versus nine in the CsA group and mean proteinuria was increased in the SRL group (0.42 ± 0.44 vs. 0.26 ± 0.37; p = 0.018). In summary, the renal benefits associated with conversion of CsA to SRL, at 3 months posttransplantation, in combination with MMF were maintained for 4 years posttransplantation.

  12. Long-term Follow-up of Kidney Transplant Recipients in the Spare-the-Nephron-Trial.

    PubMed

    Weir, Matthew R; Pearson, Thomas C; Patel, Anita; Peddi, V Ram; Kalil, Roberto; Scandling, John; Chan, Lawrence; Baliga, Prabhakar; Melton, Larry; Mulgaonkar, Shamkant; Waid, Thomas; Schaefer, Heidi; Youssef, Nasser; Anandagoda, Lali; McCollum, David; Lawson, Sibylle; Gordon, Robert

    2017-01-01

    In the Spare-the-Nephron (STN) Study, kidney transplant recipients randomized about 115 days posttransplant to convert from CNI (calcineurin inhibitor)/MMF to sirolimus (SRL)/MMF had a significantly greater improvement in measured GFR (mGFR) at 12 months compared with those kept on CNI/MMF. The difference at 24 months was not statistically significant. From 14 top enrolling centers, 128 of 175 patients identified with a functioning graft at 2 years consented to enroll in an observational, noninterventional extension study to collect retrospectively and prospectively annual follow-up data for the interval since baseline (completion of the parent STN study at 24 months posttransplant). Overall, 11 patients died, including 5 (7.6%) in the SRL/MMF group and 6 (9.7%) in the CNI/MMF group. Twenty-two grafts have been lost including 10 (15.2%) in the SRL/MMF arm and 12 (19.4%) in the CNI/MMF arm. Death and chronic rejection were the most common causes of graft loss in both arms. There were modestly more cardiovascular events in the MMF/SRL group. Estimated creatinine clearance (Cockcroft-Gault) from baseline out to 6 additional years (8 years posttransplant, ITT analysis, SRL/MMF, n = 34; CNI/MMF, n = 26) was 63.2 ± 28.5 mL/min/1.73 m in the SRL/MMF group and 59.2 ± 27.2 mL/min/1.73 m in the CNI/MMF group and was not statistically significant, but there is a clinically meaningful trend for improved long-term renal function in the SRL/MMF group compared with the CNI/MMF group. The long-term decision for immunosuppression needs to be carefully individualized.

  13. Tacrolimus with mycophenolate mofetil (MMF) or sirolimus vs. cyclosporine with MMF in cardiac transplant patients: 1-year report.

    PubMed

    Kobashigawa, J A; Miller, L W; Russell, S D; Ewald, G A; Zucker, M J; Goldberg, L R; Eisen, H J; Salm, K; Tolzman, D; Gao, J; Fitzsimmons, W; First, R

    2006-06-01

    The most advantageous combination of immunosuppressive agents for cardiac transplant recipients has not yet been established. Between November 2001 and June 2003, 343 de novo cardiac transplant recipients were randomized to receive steroids and either tacrolimus (TAC) + sirolimus (SRL), TAC + mycophenolate mofetil (MMF) or cyclosporine (CYA) + MMF. Antilymphocyte induction therapy was allowed for up to 5 days. The primary endpoint of >/=3A rejection or hemodynamic compromise rejection requiring treatment showed no significant difference at 6 months (TAC/MMF 22.4%, TAC/SRL 24.3%, CYA/MMF 31.6%, p = 0.271) and 1 year (p = 0.056), but it was significantly lower in the TAC/MMF group when compared only to the CYA/MMF group at 1 year (23.4% vs. 36.8%; p = 0.029). Differences in the incidence of any treated rejection were significant (TAC/SRL = 35%, TAC/MMF = 42%, CYA/MMF = 59%; p < 0.001), as were median levels of serum creatinine (TAC/SRL = 1.5 mg/dL, TAC/MMF = 1.3 mg/dL, CYA/MMF = 1.5 mg/dL; p = 0.032) and triglycerides (TAC/SRL = 162 mg/dL, TAC/MMF = 126 mg/dL, CYA/MMF = 154 mg/dL; p = 0.028). The TAC/SRL group encountered fewer viral infections but more fungal infections and impaired wound healing. These secondary endpoints suggest that the TAC/MMF combination appears to offer more advantages than TAC/SRL or CYA/MMF in cardiac transplant patients, including fewer >/=3A rejections or hemodynamic compromise rejections and an improved side-effect profile.

  14. Effects of Surface Heat Flux Anomalies on Stratification, Convective Growth and Vertical Transport within the Saharan Boundary Layer

    NASA Astrophysics Data System (ADS)

    Huang, Qian; Marsham, John; Parker, Doug; Tian, Wenshou; Grams, Christian; Cuesta, Juan; Flamant, Cyrille

    2010-05-01

    The very large surface sensible and very low latent heat fluxes in the Sahara desert lead to its unusually deep, almost dry-adiabatic boundary layer, that often reaches 6 km. This is often observed to consist of a shallow convective boundary layer (CBL) with a near neutral residual layer above (the Saharan Residual Layer, or SRL). It has been shown that the SRL can be both spatially extensive and persist throughout the day. Multiple near-neutral layers are frequently observed within the SRL, or within the SAL, each with a different water vapour and/or dust content, and each separated by a weak lid (e.g., Figure 1). A local maximum in not only relative humidity, but also water vapour mixing ratio (WVMR) is often seen at the top of the SRL or SAL. This structure suggests that in some locations, at some times, convection from the surface is mixing the full depth of the Saharan boundary layer, but in most locations and times this is not the case, and varying horizontal advection leads to the multiple layering observed. During the GERBILS (GERB Intercomparison of Longwave and Shortwave radiation) field campaign in the Sahara, coherent couplings were observed between surface albedo, CBL air temeperatures and CBL winds. Using two cases based on observations from GERBILS, large eddy model (LEM) simulations have been used to investigate the effects of surface flux anomalies on the growth of the summertime Saharan CBL into the Saharan Residual layer (SRL) above, and transport from the CBL into the SRL. Hot surface anomalies generated updraughts and convergence in the CBL that increased transport from the CBL into the SRL. The induced subsidence in regions away from the anomalies inhibited growth of the CBL there. If the domain-averaged surface fluxes were kept constant this led to a shallower, cooler CBL. If fluxes outside the anomalies were kept constant, so that stronger anomalies led to increased domain-averaged fluxes, this gave a warmer, shallower CBL. These effects

  15. A resource-saving collective approach to biomedical semantic role labeling

    PubMed Central

    2014-01-01

    Background Biomedical semantic role labeling (BioSRL) is a natural language processing technique that identifies the semantic roles of the words or phrases in sentences describing biological processes and expresses them as predicate-argument structures (PAS’s). Currently, a major problem of BioSRL is that most systems label every node in a full parse tree independently; however, some nodes always exhibit dependency. In general SRL, collective approaches based on the Markov logic network (MLN) model have been successful in dealing with this problem. However, in BioSRL such an approach has not been attempted because it would require more training data to recognize the more specialized and diverse terms found in biomedical literature, increasing training time and computational complexity. Results We first constructed a collective BioSRL system based on MLN. This system, called collective BIOSMILE (CBIOSMILE), is trained on the BioProp corpus. To reduce the resources used in BioSRL training, we employ a tree-pruning filter to remove unlikely nodes from the parse tree and four argument candidate identifiers to retain candidate nodes in the tree. Nodes not recognized by any candidate identifier are discarded. The pruned annotated parse trees are used to train a resource-saving MLN-based system, which is referred to as resource-saving collective BIOSMILE (RCBIOSMILE). Our experimental results show that our proposed CBIOSMILE system outperforms BIOSMILE, which is the top BioSRL system. Furthermore, our proposed RCBIOSMILE maintains the same level of accuracy as CBIOSMILE using 92% less memory and 57% less training time. Conclusions This greatly improved efficiency makes RCBIOSMILE potentially suitable for training on much larger BioSRL corpora over more biomedical domains. Compared to real-world biomedical corpora, BioProp is relatively small, containing only 445 MEDLINE abstracts and 30 event triggers. It is not large enough for practical applications, such as pathway

  16. BIOSMILE: A semantic role labeling system for biomedical verbs using a maximum-entropy model with automatically generated template features

    PubMed Central

    Tsai, Richard Tzong-Han; Chou, Wen-Chi; Su, Ying-Shan; Lin, Yu-Chun; Sung, Cheng-Lung; Dai, Hong-Jie; Yeh, Irene Tzu-Hsuan; Ku, Wei; Sung, Ting-Yi; Hsu, Wen-Lian

    2007-01-01

    Background Bioinformatics tools for automatic processing of biomedical literature are invaluable for both the design and interpretation of large-scale experiments. Many information extraction (IE) systems that incorporate natural language processing (NLP) techniques have thus been developed for use in the biomedical field. A key IE task in this field is the extraction of biomedical relations, such as protein-protein and gene-disease interactions. However, most biomedical relation extraction systems usually ignore adverbial and prepositional phrases and words identifying location, manner, timing, and condition, which are essential for describing biomedical relations. Semantic role labeling (SRL) is a natural language processing technique that identifies the semantic roles of these words or phrases in sentences and expresses them as predicate-argument structures. We construct a biomedical SRL system called BIOSMILE that uses a maximum entropy (ME) machine-learning model to extract biomedical relations. BIOSMILE is trained on BioProp, our semi-automatic, annotated biomedical proposition bank. Currently, we are focusing on 30 biomedical verbs that are frequently used or considered important for describing molecular events. Results To evaluate the performance of BIOSMILE, we conducted two experiments to (1) compare the performance of SRL systems trained on newswire and biomedical corpora; and (2) examine the effects of using biomedical-specific features. The experimental results show that using BioProp improves the F-score of the SRL system by 21.45% over an SRL system that uses a newswire corpus. It is noteworthy that adding automatically generated template features improves the overall F-score by a further 0.52%. Specifically, ArgM-LOC, ArgM-MNR, and Arg2 achieve statistically significant performance improvements of 3.33%, 2.27%, and 1.44%, respectively. Conclusion We demonstrate the necessity of using a biomedical proposition bank for training SRL systems in the

  17. Sirolimus conversion regimen versus continued calcineurin inhibitors in liver allograft recipients: a randomized trial.

    PubMed

    Abdelmalek, M F; Humar, A; Stickel, F; Andreone, P; Pascher, A; Barroso, E; Neff, G W; Ranjan, D; Toselli, L T; Gane, E J; Scarola, J; Alberts, R G; Maller, E S; Lo, C-M

    2012-03-01

    A large prospective, open-label, randomized trial evaluated conversion from calcineurin inhibitor (CNI)- to sirolimus (SRL)-based immunosuppression for preservation of renal function in liver transplantation patients. Eligible patients received liver allografts 6-144 months previously and maintenance immunosuppression with CNI (cyclosporine or tacrolimus) since early posttransplantation. In total, 607 patients were randomized (2:1) to abrupt conversion (<24 h) from CNI to SRL (n = 393) or CNI continuation for up to 6 years (n = 214). Between-group changes in baseline-adjusted mean Cockcroft-Gault GFR at month 12 (primary efficacy end point) were not significant. The primary safety end point, noninferiority of cumulative rate of graft loss or death at 12 months, was not met (6.6% vs. 5.6% in the SRL and CNI groups, respectively). Rates of death at 12 months were not significantly different, and no true graft losses (e.g. liver transplantation) were observed during the 12-month period. At 52 weeks, SRL conversion was associated with higher rates of biopsy-confirmed acute rejection (p = 0.02) and discontinuations (p < 0.001), primarily for adverse events. Adverse events were consistent with known safety profiles. In conclusion, liver transplantation patients showed no demonstrable benefit 1 year after conversion from CNI- to SRL-based immunosuppression.

  18. The Ribotoxin Restrictocin Recognizes Its RNA Substrate by Selective Engagement of Active Site Residues

    PubMed Central

    2011-01-01

    Restrictocin and related fungal endoribonucleases from the α-sarcin family site-specifically cleave the sarcin/ricin loop (SRL) on the ribosome to inhibit translation and ultimately trigger cell death. Previous studies showed that the SRL folds into a bulged-G motif and tetraloop, with restrictocin achieving a specificity of ∼1000-fold by recognizing both motifs only after the initial binding step. Here, we identify contacts within the protein−RNA interface and determine the extent to which each one contributes to enzyme specificity by examining the effect of protein mutations on the cleavage of the SRL substrate compared to a variety of other RNA substrates. As with other biomolecular interfaces, only a subset of contacts contributes to specificity. One contact of this subset is critical, with the H49A mutation resulting in quantitative loss of specificity. Maximum catalytic activity occurs when both motifs of the SRL are present, with the major contribution involving the bulged-G motif recognized by three lysine residues located adjacent to the active site: K110, K111, and K113. Our findings support a kinetic proofreading mechanism in which the active site residues H49 and, to a lesser extent, Y47 make greater catalytic contributions to SRL cleavage than to suboptimal substrates. This systematic and quantitative analysis begins to elucidate the principles governing RNA recognition by a site-specific endonuclease and may thus serve as a mechanistic model for investigating other RNA modifying enzymes. PMID:21417210

  19. Aridity increases below-ground niche breadth in grass communities

    USGS Publications Warehouse

    Butterfield, Bradley J.; Bradford, John B.; Munson, Seth M.; Gremer, Jennifer R.

    2017-01-01

    Aridity is an important environmental filter in the assembly of plant communities worldwide. The extent to which root traits mediate responses to aridity, and how they are coordinated with leaf traits, remains unclear. Here, we measured variation in root tissue density (RTD), specific root length (SRL), specific leaf area (SLA), and seed size within and among thirty perennial grass communities distributed along an aridity gradient spanning 190–540 mm of climatic water deficit (potential minus actual evapotranspiration). We tested the hypotheses that traits exhibited coordinated variation (1) among species, as well as (2) among communities varying in aridity, and (3) functional diversity within communities declines with increasing aridity, consistent with the “stress-dominance” hypothesis. Across communities, SLA and RTD exhibited a coordinated response to aridity, shifting toward more conservative (lower SLA, higher RTD) functional strategies with increasing aridity. The response of SRL to aridity was more idiosyncratic and was independent of variation in SLA and RTD. Contrary to the stress-dominance hypothesis, the diversity of SRL values within communities increased with aridity, while none of the other traits exhibited significant diversity responses. These results are consistent with other studies that have found SRL to be independent of an SLA–RTD axis of functional variation and suggest that the dynamic nature of soil moisture in arid environments may facilitate a wider array of resource capture strategies associated with variation in SRL.

  20. Semi-Rolled Leaf2 modulates rice leaf rolling by regulating abaxial side cell differentiation.

    PubMed

    Liu, Xiaofei; Li, Ming; Liu, Kai; Tang, Ding; Sun, Mingfa; Li, Yafei; Shen, Yi; Du, Guijie; Cheng, Zhukuan

    2016-04-01

    Moderate leaf rolling maintains the erectness of leaves and minimizes the shadowing between leaves which is helpful to establish ideal plant architecture. Here, we describe asrl2(semi-rolled leaf2) rice mutant, which has incurved leaves due to the presence of defective sclerenchymatous cells on the abaxial side of the leaf and displays narrow leaves and reduced plant height. Map-based cloning revealed that SRL2 encodes a novel plant-specific protein of unknown biochemical function.SRL2 was mainly expressed in the vascular bundles of leaf blades, leaf sheaths, and roots, especially in their sclerenchymatous cells. The transcriptional activities of several leaf development-related YABBY genes were significantly altered in the srl2 mutant. Double mutant analysis suggested that SRL2 and SHALLOT-LIKE1(SLL1)/ROLLED LEAF9(RL9) function in distinct pathways that regulate abaxial-side leaf development. Hence, SRL2 plays an important role in regulating leaf development, particularly during sclerenchymatous cell differentiation.

  1. Cleavage of the sarcin–ricin loop of 23S rRNA differentially affects EF-G and EF-Tu binding

    PubMed Central

    García-Ortega, Lucía; Álvarez-García, Elisa; Gavilanes, José G.; Martínez-del-Pozo, Álvaro; Joseph, Simpson

    2010-01-01

    Ribotoxins are potent inhibitors of protein biosynthesis and inactivate ribosomes from a variety of organisms. The ribotoxin α-sarcin cleaves the large 23S ribosomal RNA (rRNA) at the universally conserved sarcin–ricin loop (SRL) leading to complete inactivation of the ribosome and cellular death. The SRL interacts with translation factors that hydrolyze GTP, and it is important for their binding to the ribosome, but its precise role is not yet understood. We studied the effect of α-sarcin on defined steps of translation by the bacterial ribosome. α-Sarcin-treated ribosomes showed no defects in mRNA and tRNA binding, peptide-bond formation and sparsomycin-dependent translocation. Cleavage of SRL slightly affected binding of elongation factor Tu ternary complex (EF-Tu•GTP•tRNA) to the ribosome. In contrast, the activity of elongation factor G (EF-G) was strongly impaired in α-sarcin-treated ribosomes. Importantly, cleavage of SRL inhibited EF-G binding, and consequently GTP hydrolysis and mRNA–tRNA translocation. These results suggest that the SRL is more critical in EF-G than ternary complex binding to the ribosome implicating different requirements in this region of the ribosome during protein elongation. PMID:20215430

  2. Solvent extraction of calcium and strontium into nitrobenzene by using a synergistic mixture of hydrogen dicarbollylcobaltate and bis(diphenylphosphino)methane dioxide.

    PubMed

    Makrlík, Emanuel; Spíchal, Zdenek; Vanura, Petr; Selucký, Pavel

    2013-01-01

    Extraction of microamounts of calcium and strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of bis(diphenylphosphino)methane dioxide (DPPMDO, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, HL2+, ML2(2+), ML3(2+) and ML4(2+) (M2+ = Ca2+, Sr2+) are extracted into the organic phase. The values of extraction and stability constants of the cationic complexes in nitrobenzene saturated with water have been determined. In the considered nitrobenzene medium, it was found that the stability constants of the complexes CaL2(2+), CaL3(2+) and CaL4(2+), where L is DPPMDO, are somewhat higher than those of the corresponding complex species SrL2(2+), SrL3(2+) and SrL4(2+) with the same ligand L.

  3. Scanning Raman lidar measurements of atmospheric water vapor during a cold frontal passage

    NASA Technical Reports Server (NTRS)

    Whiteman, D. N.; Melfi, S. H.; Starr, D. O. C.; Ferrare, R. A.; Evans, K. D.; Lare, A. R.

    1995-01-01

    The NASA/Goddard Space Flight Center Scanning Raman Lidar (SRL) had a highly successful deployment at the Department of Energy Cloud and Radiation Testbed (CART) Site in Billings, OK during April, 1994 for the first Intensive Operation Period (IOP) hosted there. During the IOP, the SRL operated from just after sundown to just before sunrise for all declared evenings of operation. The lidar acquired more than 123 hours of data over 15 nights with less than 1 hour of data lost due to minor system malfunction. The SRL acquired data both on the vertical and in scanning mode toward an instrumented 60 m tower during various meteorological conditions such as an intense cold frontal passage on April 15 which is the focus of this presentation.

  4. Relations Among Cultural Learning Beliefs, Self-Regulated Learning, and Academic Achievement for Low-Income Chinese American Adolescents.

    PubMed

    Bempechat, Janine; Li, Jin; Ronfard, Samuel

    2016-12-16

    This mixed-methods study of urban low-income, English-proficient Chinese American, second-generation 15-year-olds (conducted in 2004; N = 32) examined the relation among the virtue model of learning communicated by parents and adolescents' learning beliefs, self-regulated learning (SRL) behaviors, and academic achievement. Analysis of in-depth individual interviews revealed that for these adolescents, perceptions of family educational socialization predicted students' endorsement of their culture's virtue-oriented learning beliefs and that adolescents' endorsement of these learning beliefs predicted their academic achievement. Importantly, adolescents' reported that use of SRL strategies mediated the relationship between their endorsement of virtue-oriented learning beliefs and their academic achievement. Findings are discussed in the context of further research linking cultural learning beliefs, SRL, and children's academic achievement.

  5. Academic identity formation and motivation among ethnic minority adolescents: the role of the "self" between internal and external perceptions of identity.

    PubMed

    Matthews, Jamaal S; Banerjee, Meeta; Lauermann, Fani

    2014-01-01

    Identity is often studied as a motivational construct within research on adolescent development and education. However, differential dimensions of identity, as a set of internal values versus external perceptions of social belonging, may relate to motivation in distinct ways. Utilizing a sample of 600 African American and Latino adolescents (43% female; mean age = 13.9), the present study examines whether self-regulated learning (SRL) mediates two distinct dimensions of academic identity (i.e., value and belonging) and mastery orientation. This study also examines whether self-efficacy moderates the mediating role of SRL between identity and mastery. Results show evidence for moderated mediation between SRL and academic self-efficacy. Self-regulated learning played its strongest mediating role between belonging and mastery and for low-efficacy students specifically.

  6. PSP Program close out documentation

    SciTech Connect

    Andringa, K.; Hootman, H.E.; Ferrara, A.S.; Smith, P.K.; Congdon, J.W.; Randolph, H.W.; Young, R.H.; Driggers, F.E.; Topp, S.V.

    1985-12-31

    In December 1982 DOE-SR directed SRL to study the feasibility and impact of a program to lower the U-236 content of the Highly Enriched Uranium (HEU) stockpile used as fuel for the SRP reactors. In response to this request SRL assessed four technologies, Atomic Vapor Laser Isotope Separation (AVLIS), Molecular Laser Isotope Separation (MLIS), Gas Centrifuge, and the Plasma Separation Process (PSP) for this purpose with the assistance of the Engineering Department. In April 1983 cost/benefit analyses for these processes, high spot cost estimates for production facilities, and process uncertainties were submitted to DOE-SR with a recommendation to proceed with the conceptual design and supporting development programs for a facility based on the use of the PSP process. The current program status for the PSP development program at SRL and the design and documentation of a production facility at SRP, referred to as the Fuel Improvement Demonstration Facility (FIDF), is described in this report.

  7. Analysis of Alternatives in System Capability Satisficing for Effective Acquisition

    DTIC Science & Technology

    2011-04-30

    based on a trade-off, see Figure 1(b), considered replacing a single technology (i.e., MVCS ) with another two technologies (i.e., DLS OB; DLS RMMV...http://www.SysDML.com 6 6 USV US3 BPAUV PC MVCS (USV) Combat Mgmt System MVCS (On-board)MPCE MP SRL MP SRL w/o Sea Frame MP 1 0.60 0.577 6 66 6 66...6 6 BPAUV 6 LEGEND 6 66 AN/AQS-20A AN/ASQ-235 MVCS (RMMV) 7 3 7 6 6 6 7 7 AN/WLD-1 (RMMV) 7 MP Technology Current Mission Package SRL Status Sea

  8. Research in cosmic and gamma ray astrophysics: Cosmic physics portion

    NASA Technical Reports Server (NTRS)

    Stone, Edward C.; Mewaldt, Richard A.; Schindler, Stephen

    1993-01-01

    Research in particle astrophysics at the Space Radiation Laboratory (SRL) of the California Institute of Technology is supported under NASA Grant NAGW-1919. A three-year proposal for continuation of support was submitted a year ago and put into effect 1 October 1992. This report is the combined progress report and continuation application called for under the Federal Demonstration Project. Gamma-ray Astrophysics at SRL is separately supported under NAGW-1919 and will be separately summarized and proposed. This report will document progress and plans for our particle spectroscopy activities and for related data analysis, calibration, and community service activities. A bibliography and a budget will be attached as appendices. The Caltech SRL research program includes a heavy emphasis on elemental and isotopic spectroscopy of energetic particles in the cosmic radiation; in solar, interplanetary, and anomalous 'cosmic' radiation; and in planetary magnetospheres as discussed.

  9. Investigating Flipped Learning: Student Self-Regulated Learning, Perceptions, and Achievement in an Introductory Biology Course

    NASA Astrophysics Data System (ADS)

    Sletten, Sarah Rae

    2017-01-01

    In flipped classrooms, lectures, which are normally delivered in-class, are assigned as homework in the form of videos, and assignments that were traditionally assigned as homework, are done as learning activities in class. It was hypothesized that the effectiveness of the flipped model hinges on a student's desire and ability to adopt a self-directed learning style. The purpose of this study was twofold; it aimed at examining the relationship between two variables—students' perceptions of the flipped model and their self-regulated learning (SRL) behaviors—and the impact that these variables have on achievement in a flipped class. For the study, 76 participants from a flipped introductory biology course were asked about their SRL strategy use and perceptions of the flipped model. SRL strategy use was measured using a modified version of the Motivated Strategies for Learning Questionnaire (MSLQ; Wolters et al. 2005), while the flipped perceptions survey was newly derived. Student letter grades were collected as a measure of achievement. Through regression analysis, it was found that students' perceptions of the flipped model positively predict students' use of several types of SRL strategies. However, the data did not indicate a relationship between student perceptions and achievement, neither directly nor indirectly, through SRL strategy use. Results suggest that flipped classrooms demonstrate their successes in the active learning sessions through constructivist teaching methods. Video lectures hold an important role in flipped classes, however, students may need to practice SRL skills to become more self-directed and effectively learn from them.

  10. Experience of applying the results of investigations into controlling lines of the salt ratio between the salt and pure sections of high-pressure drum boilers

    NASA Astrophysics Data System (ADS)

    Fedorov, A. I.

    2013-12-01

    Layouts of the connection of the salt ratio lines (SRLs) existing in domestic boiler building are analyzed and the main causes of their low operational efficiency are shown. The results of investigation of hydraulics and the salt mode of an internal boiler layout with the SRL of the TPE-208 boiler are presented. Recommendations on designing the SRL in internal boiler layouts of high-pressure drum boilers, which make it possible to increase the reliability of boilers and to decrease the annual consumption of phosphates, are developed.

  11. A Simulation Model to Evaluate Aircraft Survivability and Target Damage during Offensive Counterair Operations.

    DTIC Science & Technology

    1984-03-01

    srl3=tempS c calculate magnitude of vector sri--call it s2 s2=sqrt(srll**2+srl2$*2+srI3**2) c check change in slant range for possible catchup ...tempSabs(s2-sl) if(temp8.gt.5#O)then if(siogt~s2)then sl=(sl+s2)/2 .0 * else sls2 endif go to 81 endif srBs2 c post catchup calculations dmslxsrll dmsly

  12. Effects of maintenance immunosuppression with sirolimus after liver transplant for hepatocellular carcinoma.

    PubMed

    Yanik, Elizabeth L; Chinnakotla, Srinath; Gustafson, Sally K; Snyder, Jon J; Israni, Ajay K; Segev, Dorry L; Engels, Eric A

    2016-05-01

    For recipients of liver transplantations (LTs) for hepatocellular carcinoma (HCC), HCC recurrence after transplantation remains a major concern. Sirolimus (SRL), an immunosuppressant with anticarcinogenic properties, may reduce HCC recurrence and improve survival. In our study, the US Scientific Registry of Transplant Recipients was linked to pharmacy claims. For liver recipients transplanted for HCC, Cox regression was used to estimate associations of early SRL use with recurrence, cancer-specific mortality, and all-cause mortality, adjusting for recipient ethnicity, calendar year of transplant, total tumor volume, alpha-fetoprotein, transplant center size, use of interleukin 2 induction therapy, and allocated and calculated Model for End-Stage Liver Disease score. We performed stratified analyses among recipients who met Milan criteria, among those without renal failure, among those with deceased liver donors, by age at transplantation, and by tumor size. Among the 3936 included HCC LTs, 234 (6%) were SRL users. In total, there were 242 recurrences and 879 deaths, including 261 cancer-related deaths. All-cause mortality was similar in SRL users and nonusers (adjusted hazard ratio [aHR], 1.01; 95% CI, 0.73-1.39). HCC recurrence and cancer-specific mortality rates appeared lower in SRL users, but associations were not statistically significant (recurrence aHR, 0.86; 95% CI, 0.45-1.65; cancer-specific mortality aHR, 0.80; 95% CI, 0.43-1.50). Among recipients >55 years old, associations were suggestive of better outcomes for SRL users (all-cause mortality aHR, 0.62; 95% CI, 0.38-1.01; recurrence aHR, 0.52; 95% CI, 0.19-1.44; cancer-specific mortality aHR, 0.34; 95% CI, 0.11-1.09), whereas among recipients ≤55 years old, SRL users had worse outcomes (all-cause mortality aHR, 1.76; 95% CI, 1.12-2.75; recurrence aHR, 1.49; 95% CI, 0.62-3.61; cancer-specific mortality aHR, 1.54; 95% CI, 0.71-3.32). In conclusion, among HCC liver recipients overall, SRL did not appear

  13. STS-59 crew insignia

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The STS-59 insignia is dominated by Earth, reflecting the focus of the first Space Radar Laboratory (SRL-1) mission upon our planet's surface and atmosphere. The golden symbol of the astronaut corps emblem sweeps over Earth's surface from the Space Shuttle Endeavour, representing the operation of the SIR-C/Synthetic Aperture Radar (X-SAR) and the Measurement of Air Pollution from Space (MAPS) sensors. The astronaut emblem also signals the importance of the human element in space exploration and in the study of our planet. The star field visible below Earth represents the many talents and skill of the international SRL-1 team.

  14. Self-regulated Learning in a Hybrid Science Course at a Community College

    NASA Astrophysics Data System (ADS)

    Manuelito, Shannon Joy

    Community college students are attracted to courses with alternative delivery formats such as hybrid courses because the more flexible delivery associated with such courses provides convenience for busy students. In a hybrid course, face-to-face, structured seat time is exchanged for online components. In such courses, students take more responsibility for their learning because they assume additional responsibility for learning more of the course material on their own. Thus, self-regulated learning (SRL) behaviors have the potential to be useful for students to successfully navigate hybrid courses because the online components require exercise of more personal control over the autonomous learning situations inherent in hybrid courses. Self-regulated learning theory includes three components: metacognition, motivation, and behavioral actions. In the current study, this theoretical framework is used to examine how inducing self-regulated learning activities among students taking a hybrid course influence performance in a community college science course. The intervention for this action research study consisted of a suite of activities that engage students in self-regulated learning behaviors to foster student performance. The specific SRL activities included predicting grades, reflections on coursework and study efforts in course preparation logs, explanation of SRL procedures in response to a vignette, photo ethnography work on their personal use of SRL approaches, and a personalized study plan. A mixed method approach was employed to gather evidence for the study. Results indicate that community college students use a variety of self-regulated learning strategies to support their learning of course material. Further, engaging community college students in learning reflection activities appears to afford some students with opportunities to refine their SRL skills and influence their learning. The discussion focuses on integrating the quantitative and qualitative

  15. 78 FR 9364 - Certain Pasta From Italy: Notice of Final Results of 15th Antidumping Duty Administrative Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-08

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE... Administration, International Trade Administration, Department of Commerce. SUMMARY: The Department of Commerce... mandatory respondents, Pastificio Attilio Mastromauro Granoro S.r.L. (Granoro), and Rummo S.p.A. Molino...

  16. Consequences of Increased Self-Regulated Learning Opportunities on Student Teachers' Motivation and Use of Metacognitive Skills

    ERIC Educational Resources Information Center

    Vrieling, Emmy; Bastiaens, Theo; Stijnen, Sjef

    2012-01-01

    This intervention study focused on the relationships between primary student teachers' self-regulated learning (SRL) opportunities, their motivation for learning and their use of metacognitive learning strategies. The participants were 3 teacher educators and 136 first-year student teachers. During one semester, teacher educators and student…

  17. 75 FR 18806 - Certain Pasta From Italy: Preliminary Results of the 13th (2008) Countervailing Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-13

    ... Memorandum from Eric B. Greynolds to Melissa G. Skinner, dated August 4, 2004, which is on file in the...'') received countervailable subsidies and that F.lli De Cecco di Filippo Fara San Martino S.p.A. (``De Cecco... from De Matteis Agroalimentare S.p.A. (``De Matteis''); Agritalia S.r.L. (``Agritalia''); F. Divella...

  18. 77 FR 7129 - Certain Pasta From Italy: Final Results of the 2009 Countervailing Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-10

    ... Memorandum from Eric B. Greynolds to Melissa G. Skinner, dated August 4, 2004, which is on file in the... Tomasello; Pastificio Antonio Pallante S.r.L. (``Pallante''); F.lli De Cecco di Filippo Fara San Martino S.p... party or any other person: (A) Withholds information that has been requested; (B) fails to...

  19. 76 FR 23973 - Certain Pasta From Italy: Notice of Partial Rescission of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-29

    ....A.P. SNC Di Pazienza G.B. & C. (``P.A.P.''), Premiato Pastificio Afeltra S.r.L. (``Afeltra''), Pasta Zara SpA (``Zara''), Pastificio Di Martino Gaetano & F.lli SpA (``Di Martino''), Pastificio Fabianelli.... (``Garofalo''), Pastificio Riscossa F.lli ] Mastromauro S.p.A. (``Riscossa''), Rummo S.p.A. Molino...

  20. Understanding Mobile Learning from the Perspective of Self-Regulated Learning

    ERIC Educational Resources Information Center

    Sha, L.; Looi, C.-K.; Chen, W.; Zhang, B. H.

    2012-01-01

    Cognizant of the research gap in the theorization of mobile learning, this paper conceptually explores how the theories and methodology of self-regulated learning (SRL), an active area in contemporary educational psychology, are inherently suited to address the issues originating from the defining characteristics of mobile learning: enabling…

  1. Examining Self-Efficacy during Learning: Variability and Relations to Behavior, Performance, and Learning

    ERIC Educational Resources Information Center

    Bernacki, Matthew L.; Nokes-Malach, Timothy J.; Aleven, Vincent

    2015-01-01

    Self-regulated learning (SRL) theorists propose that learners' motivations and cognitive and metacognitive processes interact dynamically during learning, yet researchers typically measure motivational constructs as stable factors. In this study, self-efficacy was assessed frequently to observe its variability during learning and how learners'…

  2. The Relationship among Self-Regulated Learning, Procrastination, and Learning Behaviors in Blended Learning Environment

    ERIC Educational Resources Information Center

    Yamada, Masanori; Goda, Yoshiko; Matsuda, Takeshi; Kato, Hiroshi; Miyagawa, Hiroyuki

    2015-01-01

    This research aims to investigate the relationship among the awareness of self-regulated learning (SRL), procrastination, and learning behaviors in blended learning environment. One hundred seventy nine freshmen participated in this research, conducted in the blended learning style class using learning management system. Data collection was…

  3. Self-Regulated Learning in Virtual Communities

    ERIC Educational Resources Information Center

    Delfino, Manuela; Dettori, Giuliana; Persico, Donatella

    2008-01-01

    This paper investigates self-regulated learning (SRL) in a virtual learning community of adults interacting through asynchronous textual communication. The investigation method chosen is interaction analysis, a qualitative/quantitative approach allowing a systematic study of the contents of the messages exchanged within online communities. The…

  4. Instructional Practices and Self-Regulated Learning in Chinese Language Classes

    ERIC Educational Resources Information Center

    Lau, Kit Ling

    2012-01-01

    This study investigated the relation between teachers' instructional practices and students' self-regulated learning (SRL) in Hong Kong Chinese language classes using quantitative and qualitative methods. Participants were 1121 Grade 10 students from six secondary schools in Hong Kong. A Chinese reading comprehension (RC) test was used to assess…

  5. High and Low Computer Self-Efficacy Groups and Their Learning Behavior from Self-Regulated Learning Perspective While Engaged in Interactive Learning Modules

    ERIC Educational Resources Information Center

    Santoso, Harry B.; Lawanto, Oenardi; Becker, Kurt; Fang, Ning; Reeve, Edward M.

    2014-01-01

    The purpose of this research was to investigate high school students' computer self-efficacy (CSE) and learning behavior in a self-regulated learning (SRL) framework while utilizing an interactive learning module. The researcher hypothesizes that CSE is reflected on cognitive actions and metacognitive strategies while the students are engaged with…

  6. Trace-Based Microanalytic Measurement of Self-Regulated Learning Processes

    ERIC Educational Resources Information Center

    Siadaty, Melody; Gaševic, Dragan; Hatala, Marek

    2016-01-01

    To keep pace with today's rapidly growing knowledge-driven society, productive self-regulation of one's learning processes are essential. We introduce and discuss a trace-based measurement protocol to measure the effects of scaffolding interventions on self-regulated learning (SRL) processes. It guides tracing of learners' actions in a learning…

  7. Shaping Self-Regulation in Science Teachers' Professional Growth: Inquiry Skills

    ERIC Educational Resources Information Center

    Michalsky, Tova

    2012-01-01

    This study examined 188 preservice science teachers' professional growth along three dimensions--self-regulated learning (SRL) in a science pedagogical context, pedagogical content knowledge, and self-efficacy in teaching science--comparing four learner-centered, active-learning, peer-collaborative environments for learning to teach higher order…

  8. Raman Lidar Measurements During the International H2O Project. 2; Instrument Comparisons and Case Studies

    NASA Technical Reports Server (NTRS)

    Whiteman, D. N.; Demoz, B.; DiGirolamo, P.; Corner, J.; Veselovskii, I.; Evans, K.; Wang, Z.; Sabatino, D.; Schwemmer, G.; Gentry, B.

    2005-01-01

    The NASA/GSFC Scanning Raman Lidar (SRL) participated in the International H2O Project (IHOP) that occurred in May and June, 2002 in the midwestern part of the U. S. The SRL system configuration and methods of data analysis were described in part I of this paper. In this second part, comparisons of SRL water vapor measurements and those of chilled mirror radiosonde and LASE airborne water vapor lidar are performed. Two case studies are presented; one for daytime and one for nighttime. The daytime case study is of a convectively driven boundary layer event and is used to characterize the SRL water vapor random error characteristics. The nighttime case study is of a thunderstorm-generated cirrus cloud case that is studied in it s meteorological context. Upper tropospheric humidification due to precipitation from the cirrus cloud is quantified as is the cirrus cloud ice water content and particle depolarization ratio. These detailed cirrus cloud measurements are being used in a cirrus cloud modeling study.

  9. Self-Regulation, Coregulation, and Socially Shared Regulation: Exploring Perspectives of Social in Self-Regulated Learning Theory

    ERIC Educational Resources Information Center

    Hadwin, Allyson; Oshige, Mika

    2011-01-01

    Background/Context: Models of self-regulated learning (SRL) have increasingly acknowledged aspects of social context influence in its process; however, great diversity exists in the theoretical positioning of "social" in these models. Purpose/Objective/Research Question/Focus of Study: The purpose of this review article is to introduce and…

  10. Supporting Self-Regulated Learning for College Students with Asperger Syndrome: Exploring the "Strategies for College Learning" Model

    ERIC Educational Resources Information Center

    Ness, Bryan M.

    2013-01-01

    In this study, I piloted the feasibility, effects, and perceived acceptability of a peer mentoring intervention targeting academic achievement and self-regulated learning (SRL) for three college students with Asperger syndrome. The approach, dubbed Strategies for College Learning (SCL), features individualized assessment of academic performance in…

  11. Advanced Mass Spectrometers for Hydrogen Isotope Analyses

    SciTech Connect

    Chastagner, P.

    2001-08-01

    This report is a summary of the results of a joint Savannah River Laboratory (SRL) - Savannah River Plant (SRP) ''Hydrogen Isotope Mass Spectrometer Evaluation Program''. The program was undertaken to evaluate two prototype hydrogen isotope mass spectrometers and obtain sufficient data to permit SRP personnel to specify the mass spectrometers to replace obsolete instruments.

  12. Chinese College Students' Self Regulated Learning Strategies and Self-Efficacy Beliefs in Learning English as a Foreign Language

    ERIC Educational Resources Information Center

    Wang, Chuang; Hu, Jiyue; Zhang, Guoying; Chang, Yan; Xu, Yongjin

    2012-01-01

    Chinese college students majoring in medicine participated in this study by completing two questionnaires about their use of self-regulated learning (SRL) strategies and self-efficacy beliefs in studying English as a foreign language. Data on participants' performance on two English written exams and one oral English test were also collected.…

  13. University Students' Online Academic Help Seeking: The Role of Self-Regulation and Information Commitments

    ERIC Educational Resources Information Center

    Cheng, Kun-Hung; Liang, Jyh-Chong; Tsai, Chin-Chung

    2013-01-01

    Students' online academic help seeking (OAHS) can be facilitated by the aid of technology, but improvement in OAHS may also involve personal variables such as self-regulated learning (SRL), and "information commitments" (ICs), which are evaluative standards and strategies of online information. Accordingly, three instruments--an OAHS, an…

  14. How a Learner Self-Regulates Reading Comprehension: A Case Study for Graduate Level Reading

    ERIC Educational Resources Information Center

    Fadlelmula, Fatma Kayan; Ozgeldi, Meric

    2010-01-01

    The purpose of this study is to examine how a learner self-regulates learning while reading an academic text. In particular, the aim is not to generalize self-regulatory processes for any learning task, but to have an overall idea about how a learner self-regulates. In particular, Pintrich's SRL (self-regulated learning) model is used to find out…

  15. Pu-238 fuel form activities, January 1-31, 1982

    SciTech Connect

    Not Available

    1982-03-01

    This monthly report for /sup 238/Pu fuel form activities has two main sections: SRP-PuFF facility and SRL fuel form activities. The program status, budget information, and milestone schedules are discussed in each main section. The Work Breakdown Structure (WBS) for this program is shown. Only one monthly report per year is processed for EDB.

  16. Assessing Self-Regulated Learning in Higher Education: A Systematic Literature Review of Self-Report Instruments

    ERIC Educational Resources Information Center

    Roth, Anne; Ogrin, Sabine; Schmitz, Bernhard

    2016-01-01

    The growing interest in the field of learning strategies has led to an increasing number of studies and, with that, the development of numerous instruments to measure the use of self-regulated learning (SRL) strategies. Due to the complexity of this research field, the types of assessment methods are diverse. For this reason, we conducted a…

  17. Online Discussion and Self-Regulated Learning: Effects of Instructional Methods on Mathematical Literacy

    ERIC Educational Resources Information Center

    Kramarski, Bracha; Mizrachi, Nava

    2006-01-01

    The authors investigated the effects of online discussion embedded within metacognitive guidance on mathematical literacy and self-regulated learning (SRL). They compared 4 instructional methods: online discussion embedded within metacognitive guidance (Online+Meta), online discussion without metacognitive guidance (Online), face-to-face…

  18. Orbital Sunrise

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The STS-68 crew aboard the Space Shuttle Endeavour told a post-flight audience at JSC that this sunrise was one of the most scenic sunrises/ sunsets witnessed during the week and a half long Space Radar Laboratory (SRL-2) mission. Jutting clouds, back-lit by the dawn colors, are sandwiched between the blue airglow and the silhouetted horizon of Earth.

  19. Robotics at Savannah River site: activity report

    SciTech Connect

    Byrd, J.S.

    1984-09-01

    The objectives of the Robotics Technology Group at the Savannah River Laboratory are to employ modern industrial robots and to develop unique automation and robotic systems to enhance process operations at the Savannah River site (SRP and SRL). The incentives are to improve safety, reduce personnel radiation exposure, improve product quality and productivity, and to reduce operating costs. During the past year robotic systems have been installed to fill chemical dilution vials in a SRP laboratory at 772-F and remove radioactive waste materials in the SRL Californium Production Facility at 773-A. A robotic system to lubricate an extrusion press has been developed and demonstrated in the SRL robotics laboratory and is scheduled for installation at the 321-M fuel fabrication area. A mobile robot was employed by SRP for a radiation monitoring task at a waste tank top in H-Area. Several other robots are installed in the SRL robotics laboratories and application development programs are underway. The status of these applications is presented in this report.

  20. Grade Level, Study Time, and Grade Retention and Their Effects on Motivation, Self-Regulated Learning Strategies, and Mathematics Achievement: A Structural Equation Model

    ERIC Educational Resources Information Center

    Rosário, Pedro; Núñez, José Carlos; Valle, António; González-Pienda, Julio; Lourenço, Abílio

    2013-01-01

    The present study complements previous research findings with new data to improve our understanding of the relationship between motivational variables and academic performance in math mediated by self-regulated learning (SRL). A structural equation model with predictor (i.e., grade retention, grade level, and study time), process (i.e., perceived…

  1. Increasing the Size of the Effective United States Control Fleet

    DTIC Science & Technology

    2002-08-01

    Bottomed; DH – Double Hulled; SH – Single Hulled; SBT – Segregated Ballast Tanks 2. Esso Petrolera Argentina SRL ( Sociedad de Responsabilidad Limitada ...new name for Esso SAPA ( Sociedad Anonima Petrolera Argentin) Source: Appendix E Table 5.2, M.I.T. EUSC, Militarily Useful Tanker Fleet for June 2002 85

  2. Scaffolding Self-Regulated Learning Online: A Study in High School Mathematics Classrooms

    ERIC Educational Resources Information Center

    Kereluik, Kristen Marie

    2013-01-01

    This research explores the implementation and utilization of self-regulated learning (SRL) scaffolds (i.e. videos, journals, surveys) in online K-12 courses. This project is grounded in research on online education as well as theory and research around self-regulated learning in both online and offline contexts. This research is conducted through…

  3. Comparison of lower body strength, power, acceleration, speed, agility, and sprint momentum to describe and compare playing rank among professional rugby league players.

    PubMed

    Baker, Daniel G; Newton, Robert U

    2008-01-01

    Success in rugby league football seems heavily reliant on players possessing an adequate degree of various physical fitness qualities, such as strength, power, speed, agility, and endurance, as well as the individual skills and team tactical abilities. The purpose of this study was to describe and compare the lower body strength, power, acceleration, maximal speed, agility, and sprint momentum of elite first-division national rugby league (NRL) players (n = 20) to second-division state league (SRL) players (n = 20) players from the same club. Strength and maximal power were the best discriminators of which players were in the NRL or SRL squads. None of the sprinting tests, such as acceleration (10-m sprint), maximal speed (40-m sprint), or a unique 40-m agility test, could distinguish between the NRL or SRL squads. However, sprint momentum, which was a product of 10-m velocity and body mass, was better for discriminating between NRL and SRL players as heavier, faster players would possess better drive forward and conversely be better able to repel their opponents' drive forward. Strength and conditioning specialists should therefore pay particular attention to increasing lower body strength and power and total body mass through appropriate resistance training while maintaining or improving 10-m sprint speed to provide their players with the underlying performance characteristics of play at the elite level in rugby leagues.

  4. 77 FR 52688 - Initiation of Antidumping and Countervailing Duty Administrative Reviews and Request for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-30

    ... Sales at Less Than Fair Value: Sparklers from the People's Republic of China, 56 FR 20588 (May 6, 1991...'s Republic of China, 59 FR 22585 (May 2, 1994). In accordance with the separate rates criteria, the... e Adalberto Fratelli S.p.A Valdigrano di Flavio Pagani S.r.L Russia Federation: Solid Urea,...

  5. Teacher Beliefs, Knowledge, and Practice of Self-Regulated Learning

    ERIC Educational Resources Information Center

    Spruce, Robin; Bol, Linda

    2015-01-01

    This study examined teacher beliefs, knowledge, and classroom practice of self-regulated learning for ten elementary and middle school teachers. Using Zimmerman's SRL model to frame our method and results, we administered questionnaires, observed classrooms and conducted interviews with these teachers. Teachers had positive beliefs about the role…

  6. Training of Self-Regulated Learning Skills on a Social Network System

    ERIC Educational Resources Information Center

    Cho, Kwangsu; Cho, Moon-Heum

    2013-01-01

    The purpose of this study was to investigate whether self-regulated learning (SRL) skills trained using a social network system (SNS) may be generalized outside the training session. A total of 29 undergraduate students participated in the study. During the training session, students in the experimental group were trained to practice…

  7. The Effects of Design Strategies for Promoting Students' Self-Regulated Learning Skills on Students' Self-Regulation and Achievements in Online Learning Environments

    ERIC Educational Resources Information Center

    Cho, Moon-Heum

    2004-01-01

    The purpose of this study was to investigate the effects of design strategies for promoting students' self-regulated learning skills on students' self-regulation and achievements. Seven strategies for promoting students' SRL are identified through the literature review and applied into the experimental group: goal setting, self-evaluation,…

  8. Self-Regulation of Learning and Preference for Written versus Audio-Recorded Feedback by Distance Education Students

    ERIC Educational Resources Information Center

    Johnson, Genevieve Marie; Cooke, Audrey

    2016-01-01

    Teacher feedback is critically related to student learning. This study sought to determine the relationships between distance education (DE) student level of self-regulated learning (SRL) and their preference for audio-recorded vs. written feedback from tutors. DE students (n = 102) enrolled in a first-year university course completed an online…

  9. Safety analysis forseismic motion of control rods accounting for rod misalignment

    SciTech Connect

    Osmin, W.L.; Paik, I.K.

    1992-01-01

    The purpose of this report is to provide a summary of the results of three safety analyses performed by the SRL Safety Analysis Group (SAG) to assess the safety impact of control rod motion induced by a Design Basis Earthquake (DBE).

  10. Intraspecific variation in fine root respiration and morphology in response to in situ soil nitrogen fertility in a 100-year-old Chamaecyparis obtusa forest.

    PubMed

    Makita, Naoki; Hirano, Yasuhiro; Sugimoto, Takanobu; Tanikawa, Toko; Ishii, Hiroaki

    2015-12-01

    Soil N fertility has an effect on belowground C allocation, but the physiological and morphological responses of individual fine root segments to variations in N availability under field conditions are still unclear. In this study, the direction and magnitude of the physiological and morphological function of fine roots in response to variable in situ soil N fertility in a forest site were determined. We measured the specific root respiration (Rr) rate, N concentration and morphology of fine root segments with 1-3 branching orders in a 100-year-old coniferous forest of Chamaecyparis obtusa. Higher soil N fertility induced higher Rr rates, root N concentration, and specific root length (SRL), and lower root tissue density (RTD). In all fertility levels, the Rr rates were significantly correlated positively with root N and SRL and negatively with RTD. The regression slopes of respiration with root N and RTD were significantly higher along the soil N fertility gradient. Although no differences in the slopes of Rr and SRL relationship were found across the levels, there were significant shifts in the intercept along the common slope. These results suggest that a contrasting pattern in intraspecific relationships between specific Rr and N, RTD, and SRL exists among soils with different N fertility. Consequently, substantial increases in soil N fertility would exert positive effects on organ-scale root performance by covarying the Rr, root N, and morphology for their potential nutrient and water uptake.

  11. Evaluation of uranium geochemical anomalies in the Greenville 1/sup 0/ x 2/sup 0/ Quadrangle (Avalon, Greer, Honea, and Northeast Greenville). National Uranium Resource Evaluation program

    SciTech Connect

    Sargent, K. A.; Price, V. Jr.

    1982-08-01

    The Savannah River Laboratory (SRL) was involved in the National Uranium Resource Evaluation (NURE) from 1974 through 1981. The SRL role was to design, conduct, and report the data from a geochemical reconnaissance of almost half the continental United States. The purpose of this work was to provide a basis for evaluating the uranium potential of areas and to identify areas meriting conventional geologic followup. More than 275,000 samples of stream sediment, soil, vegetation, and ground or surface water were collected in the program. As a part of the development program to support interpretation of the geochemical data, SRL conducted a series of field studies to verify anomalies that were identified from reconnaissance data. Subcontractors were selected to conduct field scintillometer surveys, compile geologic maps, collect additional samples, or provide other services needed for a given study. This report summarizes the results of four small studies that were conducted for SRL by V.S. Griffin, Jr., in the Greenville 1/sup 0/ x 2/sup 0/ quadrangle. Normal editing was not done so the report could be released to the public before the termination of the NURE program. Thus, conceptual errors that may be present have not been corrected, and the reader is cautioned to use professional judgment in interpreting the data. These studies include original geologic maps and the results of field radioactivity measurements. 20 figures, 5 tables.

  12. Implications of Institutionalizing Self-Regulated Learning: An Analysis from Four Sociological Perspectives

    ERIC Educational Resources Information Center

    Vassallo, Stephen

    2011-01-01

    Researchers, theorists, practitioners, and policy makers have shown interest in better preparing students to self-regulate their learning. In educational psychology, researchers have developed a number of pedagogical models and instructional strategies designed to facilitate students' self-regulated learning (SRL). This effort is demonstrative of…

  13. Setting Formative Assessments in Real-World Contexts to Facilitate Self-Regulated Learning

    ERIC Educational Resources Information Center

    Tay, Hui Yong

    2015-01-01

    Some writers (Black and Wiliam in "Phi Delta Kappan" 80(2):139-148, 1998; Clark 2012; Panadero and Jonsson in "Educational Research Review" 9:129-144, 2013) have hypothesized a link between formative assessments (FA) and self-regulated learning (SRL). FA give students an opportunity to play an active role in their learning…

  14. A Self-Regulated Learning Perspective on Middle Grades Classroom Assessment

    ERIC Educational Resources Information Center

    Davis, Dennis S.; Neitzel, Carin

    2011-01-01

    The authors used self-regulated learning (SRL) as a lens for examining teachers' conceptions of assessment and their classroom assessment practices. Fifteen upper-elementary and middle school teachers participated in semistructured interviews designed to uncover their beliefs about the forms and functions of classroom assessment. Observational…

  15. Developing and Testing a Self-Regulated Learning Assessment Methodology Combined with Virtual-Patient Simulation in Medical Education

    DTIC Science & Technology

    2015-04-09

    educators assess student variables that are linked to performance deficits. However, extant assessments fall short in providing adequate diagnostic...an established assessment methodology, called SRL microanalysis,2 and used it to evaluate how students approach (forethought), monitor ( performance ...time data on students ’ motivational beliefs, strategic approaches, and adaptations to performing clinical tasks. Moreover, this approach can be

  16. Web-Based Reading Annotation System with an Attention-Based Self-Regulated Learning Mechanism for Promoting Reading Performance

    ERIC Educational Resources Information Center

    Chen, Chih-Ming; Huang, Sheng-Hui

    2014-01-01

    Due to the rapid development of information technology, web-based learning has become a dominant trend. That is, learners can often learn anytime and anywhere without being restricted by time and space. Autonomic learning primarily occurs in web-based learning environments, and self-regulated learning (SRL) is key to autonomic learning…

  17. The Influence of Self-Regulated Learning and Prior Knowledge on Knowledge Acquisition in Computer-Based Learning Environments

    ERIC Educational Resources Information Center

    Bernacki, Matthew

    2010-01-01

    This study examined how learners construct textbase and situation model knowledge in hypertext computer-based learning environments (CBLEs) and documented the influence of specific self-regulated learning (SRL) tactics, prior knowledge, and characteristics of the learner on posttest knowledge scores from exposure to a hypertext. A sample of 160…

  18. A Cross-Cultural Study of Self-Regulated Learning in a Computer-Supported Collaborative Learning Environment

    ERIC Educational Resources Information Center

    Shi, Yongchao; Frederiksen, Carl H.; Muis, Krista R.

    2013-01-01

    Self-regulated learning (SRL) actions of 30 Canadian and 30 Chinese university students were studied in a face-to-face problem-based learning environment. Participants were randomly assigned to work in dyads consisting of Chinese, Canadian, or mixed Chinese-Canadian pairs to learn Analysis of Variance collaboratively using a computer coach. Dialog…

  19. An Exploratory Study of Self-Regulated Learning Strategies in a Design Project by Students in Grades 9-12

    ERIC Educational Resources Information Center

    Lawanto, Oenardi; Butler, Deborah; Cartier, Sylvie; Santoso, Harry; Lawanto, Kevin; Clark, David

    2013-01-01

    This exploratory study evaluated self-regulated learning (SRL) strategies of 27 students in grades 9-12 during an engineering design project. The specific focus of the study was on student task interpretation and its relation to planning and cognitive strategies in design activities. Two research questions guided the study: (1) To what degree was…

  20. Self-Regulated Learning and Perceived Health among University Students Participating in Physical Activity Classes

    ERIC Educational Resources Information Center

    McBride, Ron E.; Altunsöz, Irmak Hürmeriç; Su, Xiaoxia; Xiang, Ping; Demirhan, Giyasettin

    2016-01-01

    The purpose of this study was to explore motivational indicators of self-regulated learning (SRL) and the relationship between self-regulation (SR) and perceived health among university students enrolled in physical activity (PA) classes. One hundred thirty-one Turkish students participating in physical education activity classes at two…

  1. Adjusting Curricular Design to "CREATE" a Culture of Self-Regulation

    ERIC Educational Resources Information Center

    Egan, Rylan

    2011-01-01

    Developing learners' ability to self-regulate their own learning has been an ideal sought after by researchers and practitioners alike. Over the past 40 years a plethora of educational psychology research on self-regulated learning (SRL) has flooded the literature. In this article I attempt to consolidate key theories from this literature base and…

  2. Do Different Goal-Setting Conditions Facilitate Students' Ability to Regulate Their Learning of Complex Science Topics with RiverWeb?

    ERIC Educational Resources Information Center

    Azevedo, Roger; Ragan, Susan; Cromley, Jennifer G.; Pritchett, Stacy

    This study examined the role of different goal setting instructional interventions in facilitating high school students' regulation of their conceptual understanding of ecological systems while using a Web-based water quality simulation environment. Building on the information processing theory of self-regulated learning (SRL) of P. Winne and…

  3. Helium-induced weld cracking in irradiated 304 stainless steel

    SciTech Connect

    Birchenall, A.K. )

    1989-01-01

    This report consists of slide notes for presentation to The Metallurgical Society of the American Institute of Mining, Metallurgical and Petroleum Engineers (AIME). The meeting in question will be held October 3, 1989 in Indianapolis. This presentation will be the second of three consecutive talks contributed by SRL personnel dealing with helium-induced weld cracking.

  4. Learning from Learning Kits: gStudy Traces of Students' Self-Regulated Engagements with Computerized Content

    ERIC Educational Resources Information Center

    Perry, Nancy E.; Winne, Philip H.

    2006-01-01

    Researching self-regulated learning (SRL) as a process that evolves across multiple episodes of studying poses large methodological challenges. While self-report data provide useful information about learners' perceptions of learning, these data are not reliable indicators of studying tactics learners actually use while studying, especially when…

  5. Comment on Perry and Winne's "Learning from Learning Kits: gStudy Traces of Students' Self-Regulated Engagements with Computerized Content"

    ERIC Educational Resources Information Center

    Nenniger, Peter

    2006-01-01

    The comment starts with a review of the authors' four phase model of SRL as metacognitive, motivated, and strategic where it is suggested to complete the model with aspects of motivation, emotion, and attribution. Furthermore, integrating theories about "online motivation" within the model's internal regulatory part and framing it with elements of…

  6. Supporting Self-Regulated Learning in Web 2.0 Contexts

    ERIC Educational Resources Information Center

    Huang, Yong-Ming; Huang, Yueh-Min; Wang, Chia-Sui; Liu, Chien-Hung; Sandnes, Frode Eika

    2012-01-01

    Web-based self-learning (WBSL) provides learners with a powerful means of acquiring knowledge. However, WBSL may disorient learners, especially when their skills are inadequate for regulating their learning. In this paper, a Web 2.0 self-regulated learning (Web2SRL) system based on the theory of self-regulated learning is proposed. Learners use…

  7. 75 FR 67949 - Application(s) for Duty-Free Entry of Scientific Instruments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-04

    ...] [FR Doc No: 2010-27887] DEPARTMENT OF COMMERCE International Trade Administration Application(s) for... Cultural Materials Importation Act of 1966 (Pub. L. 89-651, as amended by Pub. L. 106-36; 80 Stat. 897; 15... International, S.r.l., Italy. Intended Use: The instrument will be used on the Hobby-Eberly Telescope for...

  8. Influence of Self-Regulated Learning and Parental Education on Post-Secondary Remediation

    ERIC Educational Resources Information Center

    Orange, Carolyn; Hodges, Traci L.

    2015-01-01

    This study examines the relationship between self-regulated learning (SRL), parent education, and the need to enroll in postsecondary remedial education courses, using first year college student data from the National Center for Education Statistics (NCES) Education Longitudinal Study of 2002 (ELS: 2002). This observational study was conducted…

  9. The Role of Goal Structure in Undergraduates' Use of Self-Regulatory Processes in Two Hypermedia Learning Tasks

    ERIC Educational Resources Information Center

    Moos, Daniel C.; Azevedo, Roger

    2006-01-01

    We collected think-aloud and posttest data from 60 undergraduates to examine whether they used different proportions of self-regulated learning (SRL) variables in two related learning tasks about science topics while using a hypermedia environment. We also manipulated the goal structure of the two hypermedia learning tasks to explore whether the…

  10. Differences in Students' Metacognitive Strategy Knowledge, Motivation, and Strategy Use: A Typology of Self-Regulated Learners

    ERIC Educational Resources Information Center

    Karlen, Yves

    2016-01-01

    Metacognitive strategy knowledge, motivation, and learning strategies play an important role in self-regulated learning (SRL). However, little is known about different profiles of self-regulated learners in schools that prepare students for the university entrance certificate. The aim of this study was to examine intraindividual differences in the…

  11. Developing Self-Regulated Learners in Secondary Schools

    ERIC Educational Resources Information Center

    Salter, Prue

    2012-01-01

    This paper draws on emerging data from a doctoral study exploring how schools approach the development of self-regulated learners in Years 7-12. The research is exploring stakeholders' attitudes, beliefs, experiences and perceptions around the development of self-regulated learning (SRL) in contemporary secondary schools and how new and emerging…

  12. The Role of Self-Regulated Learning in Explaining Examination Performance of College Students in First-Semester General Chemistry

    ERIC Educational Resources Information Center

    Beckley, Scott

    2013-01-01

    Many college students struggle with first-semester general chemistry. Prior studies have shown that a student's prior knowledge of chemistry, a cognitive factor, does not account for the total variance when measured by examination scores. This study explored the role of self-regulated learning (SRL) to identify the degree of success or failure of…

  13. Semantic Role Labeling of Clinical Text: Comparing Syntactic Parsers and Features

    PubMed Central

    Zhang, Yaoyun; Jiang, Min; Wang, Jingqi; Xu, Hua

    2016-01-01

    Semantic role labeling (SRL), which extracts shallow semantic relation representation from different surface textual forms of free text sentences, is important for understanding clinical narratives. Since semantic roles are formed by syntactic constituents in the sentence, an effective parser, as well as an effective syntactic feature set are essential to build a practical SRL system. Our study initiates a formal evaluation and comparison of SRL performance on a clinical text corpus MiPACQ, using three state-of-the-art parsers, the Stanford parser, the Berkeley parser, and the Charniak parser. First, the original parsers trained on the open domain syntactic corpus Penn Treebank were employed. Next, those parsers were retrained on the clinical Treebank of MiPACQ for further comparison. Additionally, state-of-the-art syntactic features from open domain SRL were also examined for clinical text. Experimental results showed that retraining the parsers on clinical Treebank improved the performance significantly, with an optimal F1 measure of 71.41% achieved by the Berkeley parser. PMID:28269926

  14. Clustering and Profiling Students According to Their Interactions with an Intelligent Tutoring System Fostering Self-Regulated Learning

    ERIC Educational Resources Information Center

    Bouchet, Francois; Harley, Jason M.; Trevors, Gregory J.; Azevedo, Roger

    2013-01-01

    In this paper, we present the results obtained using a clustering algorithm (Expectation-Maximization) on data collected from 106 college students learning about the circulatory system with MetaTutor, an agent-based Intelligent Tutoring System (ITS) designed to foster self-regulated learning (SRL). The three extracted clusters were validated and…

  15. The Role of Self-Regulated Learning in Fostering Students' Understanding of Complex Systems with Hypermedia.

    ERIC Educational Resources Information Center

    Azevedo, Roger; Cromley, Jennifer G.

    This study examined the effectiveness of self-regulated learning (SRL) training in facilitating students' learning with hyerpermedia as indicated by both performance and process data. Undergraduate students (n=131) were randomly assigned to either a training condition on how to regulate their learning (n=63) or a no training condition (n=68) and…

  16. Using Electronic Portfolios to Foster Literacy and Self-Regulated Learning Skills in Elementary Students

    ERIC Educational Resources Information Center

    Abrami, Philip C.; Venkatesh, Vivek; Meyer, Elizabeth J.; Wade, C. Anne

    2013-01-01

    The research presented here is a continuation of a line of inquiry that explores the impacts of an electronic portfolio software called ePEARL, which is a knowledge tool designed to support the key phases of self-regulated learning (SRL)--forethought, performance, and self-reflection--and promote student learning. Participants in this study were…

  17. Students' Calibration of Knowledge and Learning Processes: Implications for Designing Powerful Software Learning Environments

    ERIC Educational Resources Information Center

    Winne, Philip H.

    2004-01-01

    Calibration concerns (a) the deviation of a person's judgment from fact, introducing notions of bias and accuracy; and metric issues regarding (b) the validity of cues' contributions to judgments and (c) the grain size of cues. Miscalibration hinders self-regulated learning (SRL). Considering calibration in the context of Winne and Hadwin's…

  18. 44 CFR 79.1 - Purpose.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., minimizing impacts to the National Flood Insurance Fund (NFIF). The rules in this part apply to the... the rules in part 78 of this subchapter. (b) The purpose of the SRL program is to: (1) Assist State and local governments in funding actions that reduce or eliminate the risk of flood damage...

  19. "More Confident Going into College": Lessons Learned from Multiple Stakeholders in a New Blended Learning Initiative

    ERIC Educational Resources Information Center

    Whiteside, Aimee L.; Garrett Dikkers, Amy; Lewis, Somer

    2016-01-01

    This article examined a blended learning initiative in a large suburban high school in the Midwestern region of the United States. It employed a single-case exploratory design approach to learn about the experience of administrators, teachers, students, and parents. Using Zimmerman's Self-Regulated Learning (SRL) Theory as a guiding framework,…

  20. The Role of Personal and Contextual Variables in College Students' Academic Achievement

    ERIC Educational Resources Information Center

    Rogers, Rachel A.

    2010-01-01

    College matriculation rates are increasing but graduation rates are failing to parallel the increased enrollment. One reason for this discrepancy may be that many college students are unable to regulate their own learning. This dissertation examined the Self-Regulated Learning (SRL; Pintrich, 2004) model in students taking Statistics in Psychology…

  1. Using Coherence Analysis to Characterize Self-Regulated Learning Behaviours in Open-Ended Learning Environments

    ERIC Educational Resources Information Center

    Segedy, James R.; Kinnebrew, John S.; Biswas, Gautam

    2015-01-01

    Researchers have long recognized the potential benefits of open-ended computer- based learning environments (OELEs) to help students develop self-regulated learning (SRL) behaviours. However, measuring self-regulation in these environments is a difficult task. In this paper, we present our work in developing and evaluating "coherence…

  2. Help Helps, but Only so Much: Research on Help Seeking with Intelligent Tutoring Systems

    ERIC Educational Resources Information Center

    Aleven, Vincent; Roll, Ido; McLaren, Bruce M.; Koedinger, Kenneth R.

    2016-01-01

    Help seeking is an important process in self-regulated learning (SRL). It may influence learning with intelligent tutoring systems (ITSs), because many ITSs provide help, often at the student's request. The Help Tutor was a tutor agent that gave in-context, real-time feedback on students' help-seeking behavior, as they were learning with an ITS.…

  3. Self-Regulated Learning and Motivation Belief Differences among Gifted and Non-Gifted Middle School Students across Achievement Levels

    ERIC Educational Resources Information Center

    Hogrebe, Jaclyn M.

    2015-01-01

    This dissertation examined self-regulated learning (SRL) and motivation beliefs (i.e., self-efficacy, perceived responsibility) across ability (i.e., gifted, advanced, average) and achievement groups (i.e., high achievers, low achievers) in a sample of 135 suburban middle school students (i.e., fifth and sixth grade). In order to expand upon…

  4. Student Self-Regulated Learning in an Urban High School: Predictive Validity and Relations between Teacher Ratings and Student Self-Reports

    ERIC Educational Resources Information Center

    Cleary, Timothy J.; Callan, Gregory L.

    2014-01-01

    This study examined the predictive validity of a teacher rating scale called the Self-Regulation Strategy Inventory-Teacher Rating Scale (SRSI-TRS) and its level of convergence with several student self-report measures of self-regulated learning (SRL). Eighty-seven high school students enrolled in one of four sections of a mathematics course in an…

  5. Self and Social Regulation of Learning during Collaborative Activities in the Classroom: The Interplay of Individual and Group Cognition

    ERIC Educational Resources Information Center

    Grau, Valeska; Whitebread, David

    2012-01-01

    The purpose of the present research was to advance the development of knowledge regarding social aspects of self-regulated learning (SRL). The study had the objective of exploring the occurrence of self and social aspects of regulation during collaborative activities within regular primary science classes. Through a multiple case study approach, 8…

  6. Does a Combination of Metaphor and Pairing Activity Help Programming Performance of Students with Different Self-Regulated Learning Level?

    ERIC Educational Resources Information Center

    Hui, Tie Hui; Umar, Irfan Naufal

    2011-01-01

    This study aims to investigate the effects of metaphors and pairing activity on programming performance of students with different self-regulated-learning (SRL) level. A total of 84 computing students were involved in this seven-week study, and they were randomly assigned either to a group that received a combination of metaphor and pair…

  7. Investigating Grit and Its Relations with College Students' Self-Regulated Learning and Academic Achievement

    ERIC Educational Resources Information Center

    Wolters, Christopher A.; Hussain, Maryam

    2015-01-01

    We investigated grit and its relations with students' self-regulated learning (SRL) and academic achievement. An ethnically diverse sample of 213 college students completed an online self-report survey that included the Grit Short scale (Duckworth and Quinn "Journal of Personality Assessment, 91(2)," 166-174, 2009), seven indicators of…

  8. The Role of Parenting in Children's Self-Regulated Learning

    ERIC Educational Resources Information Center

    Pino-Pasternak, Deborah; Whitebread, David

    2010-01-01

    This paper reports the results of a systematic literature review on empirical studies exploring relationships between parental behaviours and children's self-regulated learning (SRL). The literature search resulted in 22 studies published between 1980 and 2009. Studies were analysed in terms of their research findings and their methodological…

  9. Occurrences and Quality of Teacher and Student Strategies for Self-Regulated Learning in Hands-On Simulations

    ERIC Educational Resources Information Center

    Khaled, Anne; Gulikers, Judith; Biemans, Harm; Mulder, Martin

    2016-01-01

    For many decades, teacher-structured hands-on simulations have been used in education mainly for developing procedural and technical skills. Stimulating contemporary learning outcomes suggests more constructivist approaches. The aim of this study is to examine how self-regulated learning (SRL), an important constructivist learning environment…

  10. Landing of STS-59 Shuttle Endeavour at Edwards Air Force Base

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The main landing gear of the Space Shuttle Endeavour touches down at Edwards Air Force Base to complete the 11 day STS-59/SRL-1 mission. Landing occured at 9:54 a.m., April 20, 1994. Mission duration was 11 days, 5 hours, 49 minutes.

  11. STS-59 MAPS experiment view

    NASA Technical Reports Server (NTRS)

    1994-01-01

    STS-59's MAPS (Measurement of Air Pollution from Satellites) experiment is sending real-time data that provides the most comprehensive view of carbon monoxide concentrations on Earth ever recorded. This computer image shows a summary of 'quick look' data obtained by the MAPS instrument during its first days of operations as part of the Space Shuttle Endeavour's SRL-1 payload.

  12. Night image of New York City as seen from STS-59 Endeavour

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This 35mm night image of the New York City metropolitan area was captured by the crew of the STS-59 crew during the Space Radar Laboratory (SRL) mission. Scientists studying film from the Space Shuttle Endeavour feel this is the best nocturnal view of this region from the manned space program.

  13. Finnish Students' Reasons for Their Achievement in Classroom Activities: Focus on Features That Support Self-Regulated Learning

    ERIC Educational Resources Information Center

    Mykkänen, Arttu; Perry, Nancy; Järvelä, Sanna

    2017-01-01

    The aim of this study was to investigate how finnish students explain factors that contribute to their achievement in classroom learning activities and whether these factors are related to support of self-regulated learning (SRL) in classroom. Over seven weeks, 24 primary school students were videotaped during their typical classroom activities in…

  14. Transcultural Analysis of the Effectiveness of a Program to Promote Self-Regulated Learning in Mozambique, Chile, Portugal, and Spain

    ERIC Educational Resources Information Center

    Rosário, Pedro; Núñez, José Carlos; Trigo, Luisa; Guimarães, Carina; Fernández, Estrella; Cerezo, Rebeca; Fuentes, Sonia; Orellana, Marcela; Santibáñez, América; Fulano, Celso; Ferreira, Ângelo; Figueiredo, Mirela

    2015-01-01

    The current investigation aims at assessing the effectiveness of an intervention program designed to enhance self-regulated learning (SRL) strategies at the university level, with students from different cultural, linguistic, and educational backgrounds. The central tool of the program is a set of letters in which a fictional first-year student…

  15. The Challenge of Promoting Self-Regulated Learning among Primary School Children with a Low Socioeconomic and Immigrant Background

    ERIC Educational Resources Information Center

    Vandevelde, Sabrina; Van Keer, Hilde; Merchie, Emmelien

    2017-01-01

    The authors explore the effects of student tutoring as an approach to provide support on self-regulated learning (SRL) to fifth- and sixth-grade students with a low socioeconomic or immigrant background. In total, 401 Flemish (Belgium) students participated. A quasi-experimental study with pretest, posttest, and retention test control group design…

  16. Carrier dynamics of strain-engineered InAs quantum dots with (In)GaAs surrounding material

    NASA Astrophysics Data System (ADS)

    Nasr, O.; Chauvin, N.; Alouane, M. H. Hadj; Maaref, H.; Bru-Chevallier, C.; Sfaxi, L.; Ilahi, B.

    2017-02-01

    The present study reports on the optical properties of epitaxially grown InAs quantum dots (QDs) inserted within an InGaAs strain-reducing layer (SRL). The critical energy states in such QD structures have been identified by combining photoluminescence (PL) and photoluminescence of excitation (PLE) measurements. Carrier lifetime is investigated by time-resolved photoluminescence (TRPL), allowing us to study the impact of the composition of the surrounding materials on the QD decay time. Results showed that covering the InAs QDs with, or embedding them within, an InGaAs SRL increases the carrier dynamics, while a shorter carrier lifetime has been observed when they are grown on top of an InGaAs SRL. Investigation of the dependence of carrier lifetime on temperature showed good stability of the decay time, deduced from the consequences of improved QD confinement. The findings suggest that embedding or capping the QDs with SRL exerts optimization of their room temperature optical properties.

  17. Pattern of Task Interpretation and Self-Regulated Learning Strategies of High School Students and College Freshmen during an Engineering Design Project

    ERIC Educational Resources Information Center

    Lawanto, Oenardi; Butler, Deborah; Cartier, Sylvie C.; Santoso, Harry B.; Goodridge, Wade; Lawanto, Kevin N.; Clark, David

    2013-01-01

    The objective of this exploratory study was to describe patterns in self-regulated learning (SRL) for both high school students and college freshmen while engaged in a design activity. The main research question guiding this study was: How did high school and first-year college students self-regulate their approaches to learning when engaged in an…

  18. Examining Hypermedia Learning: The Role of Cognitive Load and Self-Regulated Learning

    ERIC Educational Resources Information Center

    Moos, Daniel

    2013-01-01

    Distinct theoretical perspectives, Cognitive Load Theory and Self-Regulated Learning (SRL) theory, have been used to examine individual differences the challenges faced with hypermedia learning. However, research has tended to use these theories independently, resulting in less robust explanations of hypermedia learning. This study examined the…

  19. Earth Surface Change as Viewed by the Spaceborne Imaging Radar-C. X-Band Synthetic Aperture Radar (SIR-C/X-SAR) and shuttle Hand-Held Photographs

    NASA Technical Reports Server (NTRS)

    Evans, D. L.; Stofan, E. R.; Jones, T. D.; Godwin, L.

    1994-01-01

    The Spaceborne Imaging Radar-C, X-Band Synthetic Aperture Radar (SIR-C/X-SAR) was launched on space shuttle Endeavour at 7:05 AM EDT, Saturday, April 9, 1994 as part of the Space Radar Lab (SRL-1). Soon after launch, the radars were activated and began arount the clock operations which lasted for the next 10 days.

  20. Parents' Support during Different Writing Tasks: A Comparison between Parents of Precocious Readers, Preschoolers, and School-Age Children

    ERIC Educational Resources Information Center

    Aram, Dorit; Besser-Biron, Shira

    2017-01-01

    The study aimed to deepen the understanding of parental sensitivity to their children's abilities and the nature of their scaffolding during writing tasks. We compared the parent-child writing interactions of three groups: precocious readers (PRs), same age preschoolers (SA), and older children with the same reading level (SRL) as the PRs. Each of…

  1. The Reality of Assessing "Authentic" Electronic Portfolios: Can Electronic Portfolios Serve as a Form of Standardized Assessment to Measure Literacy and Self-Regulated Learning at the Elementary Level?

    ERIC Educational Resources Information Center

    Bures, Eva Mary; Barclay, Alexandra; Abrami, Philip C.; Meyer, Elizabeth J.

    2013-01-01

    This study explores electronic portfolios and their potential to assess student literacy and selfregulated learning in elementary-aged children. Assessment tools were developed and include a holistic rubric that assigns a mark from 1 to 5 to self-regulated learning (SRL) and a mark to literacy, and an analytical rubric measuring multiple…

  2. Formative Assessment: Assessment Is for Self-Regulated Learning

    ERIC Educational Resources Information Center

    Clark, Ian

    2012-01-01

    The article draws from 199 sources on assessment, learning, and motivation to present a detailed decomposition of the values, theories, and goals of formative assessment. This article will discuss the extent to which formative feedback actualizes and reinforces self-regulated learning (SRL) strategies among students. Theoreticians agree that SRL…

  3. The Relationship between Self-Regulated Learning Strategies and Student Academic Performance in Flipped Instructional Environments

    ERIC Educational Resources Information Center

    Long, Janna B.

    2016-01-01

    The purpose of this study was to investigate the relationship between self-regulated learning (SRL) strategies and student academic performance. Academic performance was measured by final grade (out of 100 points) in courses that were part of the study, and self-regulated learning strategies were assessed by the Motivated Strategies for Learning…

  4. Investigating Preservice Teachers' Professional Growth in Self-Regulated Learning Environments

    ERIC Educational Resources Information Center

    Kramarski, Bracha; Michalsky, Tova

    2009-01-01

    Educational reforms have suggested that the ability to self-regulate learning is essential for teachers' professional growth during their entire career as well as for their ability to promote these processes among students. This study observed teachers' professional growth along 3 dimensions: self-regulated learning (SRL) in pedagogical context,…

  5. Semantic Role Labeling of Clinical Text: Comparing Syntactic Parsers and Features.

    PubMed

    Zhang, Yaoyun; Jiang, Min; Wang, Jingqi; Xu, Hua

    2016-01-01

    Semantic role labeling (SRL), which extracts shallow semantic relation representation from different surface textual forms of free text sentences, is important for understanding clinical narratives. Since semantic roles are formed by syntactic constituents in the sentence, an effective parser, as well as an effective syntactic feature set are essential to build a practical SRL system. Our study initiates a formal evaluation and comparison of SRL performance on a clinical text corpus MiPACQ, using three state-of-the-art parsers, the Stanford parser, the Berkeley parser, and the Charniak parser. First, the original parsers trained on the open domain syntactic corpus Penn Treebank were employed. Next, those parsers were retrained on the clinical Treebank of MiPACQ for further comparison. Additionally, state-of-the-art syntactic features from open domain SRL were also examined for clinical text. Experimental results showed that retraining the parsers on clinical Treebank improved the performance significantly, with an optimal F1 measure of 71.41% achieved by the Berkeley parser.

  6. Probabilities of Natural Events Occurring at Savannah River Plant

    SciTech Connect

    Huang, J.C.

    2001-07-17

    This report documents the comprehensive evaluation of probability models of natural events which are applicable to Savannah River Plant. The probability curves selected for these natural events are recommended to be used by all SRP/SRL safety analysts. This will ensure a consistency in analysis methodology for postulated SAR incidents involving natural phenomena.

  7. Performance improvement of GaN-based near-UV LEDs with InGaN/AlGaN superlattices strain relief layer and AlGaN barrier

    NASA Astrophysics Data System (ADS)

    Jia, Chuanyu; Yu, Tongjun; Feng, Xiaohui; Wang, Kun; Zhang, Guoyi

    2016-09-01

    The carrier confinement effect and piezoelectric field-induced quantum-confined stark effect of different GaN-based near-UV LED samples from 395 nm to 410 nm emission peak wavelength were investigated theoretically and experimentally. It is found that near-UV LEDs with InGaN/AlGaN multiple quantum wells (MQWs) active region have higher output power than those with InGaN/GaN MQWs for better carrier confinement effect. However, as emission peak wavelength is longer than 406 nm, the output power of the near-UV LEDs with AlGaN barrier is lower than that of the LEDs with GaN barrier due to more serious spatial separation of electrons and holes induced by the increase of piezoelectric field. The N-doped InGaN/AlGaN superlattices (SLs) were adopted as a strain relief layer (SRL) between n-GaN and MQWs in order to suppress the polarization field. It is demonstrated the output power of near-UV LEDs is increased obviously by using SLs SRL and AlGaN barrier for the discussed emission wavelength range. Besides, the forward voltage of near-UV LEDs with InGaN/AlGaN SLs SRL is lower than that of near-UV LEDs without SRL.

  8. Future Time Orientation and Learning Conceptions: Effects on Metacognitive Strategies, Self-Efficacy Beliefs, Study Effort and Academic Achievement

    ERIC Educational Resources Information Center

    Gutiérrez-Braojos, Calixto

    2015-01-01

    During the past decade, research on the constructive learning process has been conducted mainly from two perspectives: student approaches to learning (SAL) and self-regulated learning (SRL). The SAL perspective has highlighted the role of learning conceptions with respect to other topics involved in constructive learning processes, whereas…

  9. Space shuttle observations of terrestrial impact structures using SIR-C and X-SAR radars

    NASA Astrophysics Data System (ADS)

    McHone, John F.; Greeley, Ronald; Williams, Kevin K.; Blumberg, Dan G.; Kuzmin, Ruslan O.

    2002-03-01

    Ten terrestrial impact structures were imaged during two flights of the 1994 Space Radar Laboratory (SRL) experiment. These craters include Wolf Creek, Australia; Roter Kamm, Namibia; Zhamanshin, Kazakhstan; B.P. and Oasis, Libya; Aorounga, Chad; Amguid, Algeria; and Spider, Connolly Basin and Henbury, Australia. SRL contained two co-registered instruments; the United States SIR-C polarimetric radar system operating in L-band (?=24 cm) and C-band (?=5.6 cm), and the joint German/Italian X-SAR vertically-polarized radar operating in X-band (?=3 cm). Comparisons show SRL images to be complementary to, or in some cases superior to, corresponding optical images for evaluating size, location, and relative age of impact features. Regardless of wavelength or polarization, craters with significant relief appear prominently on radar as a result of slope and roughness effects. In desert regions, longer wavelengths penetrate dry sand mantles to reveal hidden crater dimensions or associated buried landforms. Radar polarities and wavelengths are particularly sensitive to vegetation, surface roughness, and soil moisture or electrical properties. In the more temperate environments of Kazakhstan and Australia, SRL images show detailed stream patterns that reveal the location and structure of otherwise obscured impact features.

  10. Using Formative Assessment and Self-Regulated Learning to Help Developmental Mathematics Students Achieve: A Multi-Campus Program

    ERIC Educational Resources Information Center

    Hudesman, John; Crosby, Sara; Ziehmke, Niesha; Everson, Howard; Issac, Sharlene; Flugman, Bert; Zimmerman, Barry; Moylan, Adam

    2014-01-01

    The authors describe an Enhanced Formative Assessment and Self-Regulated Learning (EFA-SRL) program designed to improve the achievement of community college students enrolled in developmental mathematics courses. Their model includes the use of specially formatted quizzes designed to assess both the students' mathematics and metacognitive skill…

  11. Collaborating with Front-Line Teachers to Incorporate Self-Regulated Learning in Chinese Language Classes

    ERIC Educational Resources Information Center

    Lau, Kit-ling

    2011-01-01

    This study aimed to initially explore the possibility of helping front-line teachers to integrate the principles of self-regulated learning (SRL) into Chinese reading instruction in a 1-year collaborative project. A total of 197 Secondary 3 students and 6 Chinese language teachers from a secondary school in Hong Kong participated in the study. The…

  12. The Role of Teacher's Initiation in Online Pedagogy

    ERIC Educational Resources Information Center

    Tsai, Chia-Wen

    2012-01-01

    Purpose: The author redesigned a course titled "Applied Information Technology: Networking" and applied online collaborative learning (CL) with initiation and self-regulated learning (SRL) to improve students' involvement in this course in an environment that is full of free online games, shopping websites, and social networking…

  13. Toward Reconciling Magnitude Discrepancies Estimated from Paleoearthquake Data

    SciTech Connect

    N. Seth Carpenter; Suzette J. Payne; Annette L. Schafer

    2012-06-01

    We recognize a discrepancy in magnitudes estimated for several Basin and Range, U.S.A. faults. For example, magnitudes predicted for the Wasatch (Utah), Lost River (Idaho), and Lemhi (Idaho) faults from fault segment lengths (L{sub seg}) where lengths are defined between geometrical, structural, and/or behavioral discontinuities assumed to persistently arrest rupture, are consistently less than magnitudes calculated from displacements (D) along these same segments. For self-similarity, empirical relationships (e.g. Wells and Coppersmith, 1994) should predict consistent magnitudes (M) using diverse fault dimension values for a given fault (i.e. M {approx} L{sub seg}, should equal M {approx} D). Typically, the empirical relationships are derived from historical earthquake data and parameter values used as input into these relationships are determined from field investigations of paleoearthquakes. A commonly used assumption - grounded in the characteristic-earthquake model of Schwartz and Coppersmith (1984) - is equating L{sub seg} with surface rupture length (SRL). Many large historical events yielded secondary and/or sympathetic faulting (e.g. 1983 Borah Peak, Idaho earthquake) which are included in the measurement of SRL and used to derive empirical relationships. Therefore, calculating magnitude from the M {approx} SRL relationship using L{sub seg} as SRL leads to an underestimation of magnitude and the M {approx} L{sub seg} and M {approx} D discrepancy. Here, we propose an alternative approach to earthquake magnitude estimation involving a relationship between moment magnitude (Mw) and length, where length is L{sub seg} instead of SRL. We analyze seven historical, surface-rupturing, strike-slip and normal faulting earthquakes for which segmentation of the causative fault and displacement data are available and whose rupture included at least one entire fault segment, but not two or more. The preliminary Mw {approx} L{sub seg} results are strikingly consistent

  14. The effect of hypothermia on influx of leukocytes in the digital lamellae of horses with oligofructose-induced laminitis.

    PubMed

    Godman, Jennifer D; Burns, Teresa A; Kelly, Carlin S; Watts, Mauria R; Leise, Britta S; Schroeder, Eric L; van Eps, Andrew W; Belknap, James K

    2016-10-01

    Sepsis-related laminitis (SRL) is a common complication in the septic/endotoxemic critically-ill equine patient, in which lamellar injury and failure commonly lead to crippling distal displacement of the distal phalanx. Similar to organ injury in human sepsis, lamellar injury in SRL has been associated with inflammatory events, including the influx of leukocytes into the lamellar tissue and markedly increased expression of a wide array of inflammatory mediators at the onset of Obel grade 1 (OG1) laminitis. The only treatment reported both clinically and experimentally to protect the lamellae in SRL, local hypothermia ("cryotherapy"), has been demonstrated to effectively inhibit lamellar expression of multiple inflammatory mediators when initiated at the time of administration of a carbohydrate overload in experimental models of SRL. However, the effect of hypothermia on leukocyte influx into affected tissue has not been assessed. We hypothesized that cryotherapy inhibits leukocyte emigration into the digital lamellae in SRL. Immunohistochemical staining using leukocyte markers MAC387 (marker of neutrophils, activated monocytes) and CD163 (monocyte/macrophage-specific marker) was performed on archived lamellar tissue samples from an experimental model of SRL in which one forelimb was maintained at ambient temperature (AMB) and one forelimb was immersed in ice water (ICE) immediately following enteral oligofructose administration (10g/kg, n=14 horses). Lamellae were harvested at 24h post-oligofructose administration (DEV, n=7) or at the onset of OG1 laminitis (OG1, n=7). Both MAC387-positive and CD163-positive cells were counted by a single blinded investigator on images [n=10 (40× fields/digit for MAC387 and 20x fields/digit for CD163)] obtained using Aperio microscopy imaging analysis software. Data were assessed for normality and analyzed with a paired t-test and one-way ANOVA with significance set at p<0.05. MAC387-positive cells were present in low numbers in

  15. A Prospective, Multinational Pharmacoepidemiological Study of Clinical Conversion to Sirolimus Immunosuppression after Renal Transplantation

    PubMed Central

    Kasiske, Bertram L.; Nashan, Bjorn; Del Carmen Rial, Maria; Raffaele, Pablo; Russ, Graeme; Campistol, Josep; Pescovitz, Mark D.; Keown, Paul A.

    2012-01-01

    This prospective pharmacoepidemiological study examined treatment and outcomes in patients converted to sirolimus (SRL) after renal transplantation. 484 subjects in 36 centres in 7 countries were followed for up to 5 years. Principal reasons for conversion were declining graft function (146/484, 30%) and side effects of prior therapy (144/484, 30%) and the major treatment combinations after conversion were SRL ± MMF (62%), SRL + TAC (21.5%), SRL + CSA (16.5%). The cumulative probability of biopsy-confirmed acute rejection (BCAR) was 5% (n = 22), death-censored graft loss 12% (n = 56) and death 6% (n = 22), and there was no significant relationship to the treatment combination employed. Median calculated creatinine clearance was 48.4 (29.3, 64.5) mL/min at conversion, rising to 54.1 (41.2, 69.0) mL/min at month 1, 55.7 (39.0, 73.0) mL/min at month 12, 58.6 (39.7, 75.2) mL/min at two years and 60.9 (36.0, 77.0) mL/min at three years post-conversion. The most common adverse events were hypertension (47%), hyperlipidemia (26%), urinary tract infections (25%), anaemia (24%) and diarrhea (14%), and cardiac events, hyperlipemia and CMV infection were more common in patients converted during the first year. SRL was most frequently combined with MMF after conversion, but principal clinical outcomes were not significantly influenced by the treatment combination employed in normal practice. PMID:22934151

  16. Observation of Electron-Beam-Induced Phase Evolution Mimicking the Effect of the Charge–Discharge Cycle in Li-Rich Layered Cathode Materials Used for Li Ion Batteries

    SciTech Connect

    Lu, Ping; Yan, Pengfei; Romero, Eric; Spoerke, Erik David; Zhang, Ji-Guang; Wang, Chong-Min

    2015-01-27

    Capacity loss, and voltage decrease upon electrochemical charge-discharge cycling observed in lithium-rich layered cathode oxides (Li[LixMnyTM1-x-y]O2, TM = Ni, Co or Fe) have recently been attributed to the formation of a surface reconstructed layer (SRL) that evolves from a thin (<2 nm), defect spinel layer upon the first charge, to a relatively thick (~5nm), spinel or rock-salt layer upon continuous charge-discharge cycling. Here we report observations of a SRL and structural evolution of the SRL on the Li[Li0.2Ni0.2Mn0.6]O2 (LNMO) particles, which are identical to those reported due to the charge-discharge cycle but are a result of electron-beam irradiation during scanning transmission electron microscopy (STEM) imaging. Sensitivity of the lithium-rich layered oxides to high-energy electrons leads to the formation of thin, defect spinel layer on surfaces of the particles when exposed to a 200kV electron beam for as little as 30 seconds under normal high-resolution STEM imaging conditions. Further electron irradiation produces a thicker layer of the spinel phase, ultimately producing a rock-salt layer at a higher electron exposure. Atomic-scale chemical mapping by electron dispersive X-ray spectroscopy in STEM indicates the electron-beam-induced SRL formation on LNMO is accomplished by migration of the transition metal ions to the Li sites without breaking down the lattice. The observation through this study provides an insight for understanding the mechanism of forming the SRL and also possibly a mean to study structural evolution in the Li-rich layered oxides without involving the electrochemistry.

  17. Observation of Electron-Beam-Induced Phase Evolution Mimicking the Effect of the Charge–Discharge Cycle in Li-Rich Layered Cathode Materials Used for Li Ion Batteries

    DOE PAGES

    Lu, Ping; Yan, Pengfei; Romero, Eric; ...

    2015-01-27

    Capacity loss, and voltage decrease upon electrochemical charge-discharge cycling observed in lithium-rich layered cathode oxides (Li[LixMnyTM1-x-y]O2, TM = Ni, Co or Fe) have recently been attributed to the formation of a surface reconstructed layer (SRL) that evolves from a thin (<2 nm), defect spinel layer upon the first charge, to a relatively thick (~5nm), spinel or rock-salt layer upon continuous charge-discharge cycling. Here we report observations of a SRL and structural evolution of the SRL on the Li[Li0.2Ni0.2Mn0.6]O2 (LNMO) particles, which are identical to those reported due to the charge-discharge cycle but are a result of electron-beam irradiation during scanningmore » transmission electron microscopy (STEM) imaging. Sensitivity of the lithium-rich layered oxides to high-energy electrons leads to the formation of thin, defect spinel layer on surfaces of the particles when exposed to a 200kV electron beam for as little as 30 seconds under normal high-resolution STEM imaging conditions. Further electron irradiation produces a thicker layer of the spinel phase, ultimately producing a rock-salt layer at a higher electron exposure. Atomic-scale chemical mapping by electron dispersive X-ray spectroscopy in STEM indicates the electron-beam-induced SRL formation on LNMO is accomplished by migration of the transition metal ions to the Li sites without breaking down the lattice. The observation through this study provides an insight for understanding the mechanism of forming the SRL and also possibly a mean to study structural evolution in the Li-rich layered oxides without involving the electrochemistry.« less

  18. Observation Of Electron-beam-induced Phase Evolution Mimicking The Effect Of Charge-discharge Cycle In Li-rich Layered Cathode Materials Used For Li-ion Batteries

    SciTech Connect

    Lu, Ping; Yan, Pengfei; Romero, Eric; Spoerke, Erik D.; Zhang, Jiguang; Wang, Chong M.

    2015-02-24

    Capacity loss, and voltage fade upon electrochemical charge-discharge cycling observed in lithium-rich layered cathode oxides (Li[LixMnyTM1-x-y]O2 , TM = Ni, Co or Fe) have recently been identified to be correlated to the gradual phase transformation, featuring the formation of a surface reconstructed layer (SRL) that evolves from a thin (<2 nm), defect spinel layer upon the first charge, to a relatively thick (~5 nm), spinel or rock-salt layer upon continuous charge-discharge cycling. Here we report observations of a SRL and structural evolution of the SRL on the Li[Li0.2Ni0.2Mn0.6]O2 (LMR) particles, which are identical to those reported due to the charge-discharge cycle but are a result of electron-beam irradiation during scanning transmission electron microscopy (STEM) imaging. Sensitivity of the lithium-rich layered oxides to high-energy electrons leads to the formation of thin, defect spinel layer on surfaces of the particles when exposed to a 200 kV electron beam for as little as 30 seconds under normal high-resolution STEM imaging conditions. Further electron irradiation produces a thicker layer of the spinel phase, ultimately producing a rock-salt layer at a higher electron exposure. Atomic-scale chemical mapping by energy dispersive X-ray spectroscopy in STEM indicates the electron-beam-induced SRL formation on LMR is accomplished by migration of the transition metal ions to the Li sites without breaking down the lattice. This study provides an insight for understanding the mechanism of forming the SRL and also possibly a mean to study structural evolution in the Li-rich layered oxides without involving the electrochemistry.

  19. Two semiconductor ring lasers coupled by a single-waveguide for optical memory operation

    NASA Astrophysics Data System (ADS)

    Van der Sande, Guy; Coomans, Werner; Gelens, Lendert

    2014-05-01

    Semiconductor ring lasers are semiconductor lasers where the laser cavity consists of a ring-shaped waveguide. SRLs are highly integrable and scalable, making them ideal candidates for key components in photonic integrated circuits. SRLs can generate light in two counterpropagating directions between which bistability has been demonstrated. Hence, information can be coded into the emission direction. This bistable operation allows SRLs to be used in systems for all-optical switching and as all-optical memories. For the demonstration of fast optical flip-flop operation, Hill et al. [Nature 432, 206 (2004)] fabricated two SRLs coupled by a single waveguide, rather than a solitary SRL. Nevertheless, the literature shows that a single SRL can also function perfectly as an all-optical memory. In our recent paper [W. Coomans et al., Phys. Rev. A 88, 033813, (2013)], we have raised the question whether coupling two SRLs to realize a single optical memory has any advantage over using a solitary SRL, taking into account the obvious disadvantage of a doubled footprint and power consumption. To provide the answer, we have presented in that paper a numerical study of the dynamical behavior of semiconductor ring lasers coupled by a single bus waveguide, both when weakly coupled and when strongly coupled. We have provided a detailed analysis of the multistable landscape in the coupled system, analyzed the stability of all solutions and related the internal dynamics in the individual lasers to the field effectively measured at the output of the waveguide. We have shown which coupling phases generally promote instabilities and therefore need to be avoided in the design. Regarding all-optical memory operation, we have demonstrated that there is no real advantage for bistable memory operation compared to using a solitary SRL. An increased power suppression ratio has been found to be mainly due to the destructive interference of the SRL fields at the low power port. Also

  20. Medical students' self-efficacy in problem-based learning and its relationship with self-regulated learning.

    PubMed

    Demirören, Meral; Turan, Sevgi; Öztuna, Derya

    2016-01-01

    Background Problem-based learning (PBL) is most commonly used in medical education to enhance self-regulated learning (SRL) skills. Self-efficacy beliefs affect students' motivation through self-regulatory processes. The purpose of this study is to examine the relationship between medical students' self-reported SRL skills and their self-efficacy in PBL. Methods A cross-sectional study was conducted with second (286; 83.1%) and third (275; 80.2%) year students at the Ankara University School of Medicine. The SRL perception (SRLP) scale and self-efficacy for problem-based learning (SPBL) scale were used in the study. Results The SRLP subscales were positively correlated with the SPBL subscales. There was a weak but meaningful correlation between the subscales of SRLP (with the exception of the lack of self-directedness scale) and the subscales of SPBL and the students' views on benefiting from PBL. The female students' mean score was higher for the 'planning and goal setting' subscale of SRLP (p=0.017), and the second-year students' mean score was higher than that of the third-year students for the 'lack of self-directedness' subscale of SRLP (p=0.001) with small effect sizes (Cohen's d is 0.17 and 0.27). There was no statistically significant difference between the year and subscales of SPBL. With regard to gender, the female students had higher scores than the male students on the 'responsibility' subscale of SPBL (p=0.003; Cohen's d=0.26). Conclusions The study showed that medical students used SRL skills and believed in their ability to learn effectively in the PBL context and demonstrated the relationship between SRL skills and self-efficacy beliefs. Monitoring students' development in these skills and giving them feedback could be beneficial for the cognitive achievement of students with learning difficulties and insufficient study skills. Further studies need to be undertaken to investigate issues such as the curriculum, learning environment, individual

  1. Medical students’ self-efficacy in problem-based learning and its relationship with self-regulated learning

    PubMed Central

    Demirören, Meral; Turan, Sevgi; Öztuna, Derya

    2016-01-01

    Background Problem-based learning (PBL) is most commonly used in medical education to enhance self-regulated learning (SRL) skills. Self-efficacy beliefs affect students’ motivation through self-regulatory processes. The purpose of this study is to examine the relationship between medical students’ self-reported SRL skills and their self-efficacy in PBL. Methods A cross-sectional study was conducted with second (286; 83.1%) and third (275; 80.2%) year students at the Ankara University School of Medicine. The SRL perception (SRLP) scale and self-efficacy for problem-based learning (SPBL) scale were used in the study. Results The SRLP subscales were positively correlated with the SPBL subscales. There was a weak but meaningful correlation between the subscales of SRLP (with the exception of the lack of self-directedness scale) and the subscales of SPBL and the students’ views on benefiting from PBL. The female students’ mean score was higher for the ‘planning and goal setting’ subscale of SRLP (p=0.017), and the second-year students’ mean score was higher than that of the third-year students for the ‘lack of self-directedness’ subscale of SRLP (p=0.001) with small effect sizes (Cohen's d is 0.17 and 0.27). There was no statistically significant difference between the year and subscales of SPBL. With regard to gender, the female students had higher scores than the male students on the ‘responsibility’ subscale of SPBL (p=0.003; Cohen's d=0.26). Conclusions The study showed that medical students used SRL skills and believed in their ability to learn effectively in the PBL context and demonstrated the relationship between SRL skills and self-efficacy beliefs. Monitoring students’ development in these skills and giving them feedback could be beneficial for the cognitive achievement of students with learning difficulties and insufficient study skills. Further studies need to be undertaken to investigate issues such as the curriculum, learning

  2. Solitary and coupled semiconductor ring lasers as optical spiking neurons.

    PubMed

    Coomans, W; Gelens, L; Beri, S; Danckaert, J; Van der Sande, G

    2011-09-01

    We theoretically investigate the possibility of generating pulses in an excitable (asymmetric) semiconductor ring laser (SRL) using optical trigger pulses. We show that the phase difference between the injected field and the electric field inside the SRL determines the direction of the perturbation in phase space. Due to the folded shape of the excitability threshold, this has an important influence on the ability to cross it. A mechanism for exciting multiple consecutive pulses using a single trigger pulse (i.e., multipulse excitability) is revealed. We furthermore investigate the possibility of using asymmetric SRLs in a coupled configuration, which is a first step toward an all-optical neural network using SRLs as building blocks.

  3. Solitary and coupled semiconductor ring lasers as optical spiking neurons

    NASA Astrophysics Data System (ADS)

    Coomans, W.; Gelens, L.; Beri, S.; Danckaert, J.; van der Sande, G.

    2011-09-01

    We theoretically investigate the possibility of generating pulses in an excitable (asymmetric) semiconductor ring laser (SRL) using optical trigger pulses. We show that the phase difference between the injected field and the electric field inside the SRL determines the direction of the perturbation in phase space. Due to the folded shape of the excitability threshold, this has an important influence on the ability to cross it. A mechanism for exciting multiple consecutive pulses using a single trigger pulse (i.e., multipulse excitability) is revealed. We furthermore investigate the possibility of using asymmetric SRLs in a coupled configuration, which is a first step toward an all-optical neural network using SRLs as building blocks.

  4. Electrostatic Interactions Guide the Active Site Face of a Structure-Specific Ribonuclease to Its RNA Substrate†

    PubMed Central

    2008-01-01

    Restrictocin, a member of the α-sarcin family of site-specific endoribonucleases, uses electrostatic interactions to bind to the ribosome and to RNA oligonucleotides, including the minimal specific substrate, the sarcin/ricin loop (SRL) of 23S−28S rRNA. Restrictocin binds to the SRL by forming a ground-state E:S complex that is stabilized predominantly by Coulomb interactions and depends on neither the sequence nor structure of the RNA, suggesting a nonspecific complex. The 22 cationic residues of restrictocin are dispersed throughout this protein surface, complicating a priori identification of a Coulomb interacting surface. Structural studies have identified an enzyme−substrate interface, which is expected to overlap with the electrostatic E:S interface. Here, we identified restrictocin residues that contribute to binding in the E:S complex by determining the salt dependence [∂ log(k2/K1/2)/∂ log[KCl

  5. Growth and properties of the MOVPE GaAs/InAs/GaAsSb quantum dot structures

    NASA Astrophysics Data System (ADS)

    Hospodková, A.; Oswald, J.; Pangrác, J.; Kuldová, K.; Zíková, M.; Vyskočil, J.; Hulicius, E.

    2016-01-01

    This review paper summarizes some of results achieved during last years of our quantum dot (QD) research. We show that the QD shape (aspect ratio and elongation) significantly influences the QD photoluminescence (PL) spectrum. Magnetophotoluminescence can be used for determination of the anisotropy of QDs. While the calculated shifts in magnetic field of the energies of higher radiative transitions are found to be sensitive to the lateral elongation, the shift of the lowest transition is determined mainly by the exciton effective mass. This behavior can be used for determining both the effective mass and the elongation fairly reliably from the magnetophotoluminescence spectra displaying at least two resolved bands. Lateral shape of InAs/GaAs QDs in vertically correlated structures was also studied. We found the ways to control the QD elongation and consequently the energy difference between PL transitions by adjusting properly the spacer layer thickness. The main goal was to redshift QD PL emission towards telecommunication wavelengths of Metal Organic Vapor Phase Epitaxy prepared InAs/GaAs QDs using InGaAs or GaAsSb covering strain reducing layer (SRL). Our results proved that GaAsSb SRL improves the QD PL properties and the type I or type II band alignment can be controlled by both, GaAsSb composition and QD size. Maintaining the type I heterostructure is important for high luminescence efficiency and emission wavelength stability of QD structure. The simulation of electron structure in InAs QDs covered with GaAsSb SRL and experimental results reveal the importance of increasing QD size for obtaining a longer wavelength PL from the type I heterostructure. The type II structure of InAs/GaAs QDs covered by GaAsSb SRL with Sb content near 30% enabled us to achieve extremely long emission wavelength at 1.8 μm. The high amount of antimony in the SRL causes the preservation of QD size, and increased QD size prolongs the PL wavelength. The type II heterostructures with

  6. Correlation of bubble rise velocity and volume

    SciTech Connect

    Burge, C.

    1991-01-01

    This project was conducted at Westinghouse's Savannah River Laboratories (SRL). The goal of SRL is to make certain that the modifications on the reactor are safe for those working at the plant as well as the general public. One of the steps needed to insure safety is the knowledge of the occurrences that result from a plenum pipe breakage. When a plenum pipe breaks, two things occur: air is sucked into the pipe and is trapped in the cooling water; and water used to cool the fuel rods is lost. As a result of these occurrences, the water is slowed down by both the loss in water pressure and the upward force of air bubbles pushing against the downward force of the water. The project required the conducting of tests to find the bubble velocity in an annular ribbed pipe filled with stagnant water. This document discusses the methodology and results of this testing.

  7. Correlation of bubble rise velocity and volume

    SciTech Connect

    Burge, C.

    1991-12-31

    This project was conducted at Westinghouse`s Savannah River Laboratories (SRL). The goal of SRL is to make certain that the modifications on the reactor are safe for those working at the plant as well as the general public. One of the steps needed to insure safety is the knowledge of the occurrences that result from a plenum pipe breakage. When a plenum pipe breaks, two things occur: air is sucked into the pipe and is trapped in the cooling water; and water used to cool the fuel rods is lost. As a result of these occurrences, the water is slowed down by both the loss in water pressure and the upward force of air bubbles pushing against the downward force of the water. The project required the conducting of tests to find the bubble velocity in an annular ribbed pipe filled with stagnant water. This document discusses the methodology and results of this testing.

  8. Survey of digital imaging technology and applications at the Savannah River Site

    SciTech Connect

    Not Available

    1989-10-09

    An introduction to methods of digital image analysis is presented. Modern commercially available digital image analysis systems are described, along with applications that may be useful to programs at the Savannah River Site (SRS). Systems to aid inspection of tritium reservoir fill stems and a system to enhance inspection of radiographs of pinch weld closures of tritium reservoirs have already been developed at SRS. Modern digital analysis systems based on personal computers have been and are being procured for use in Savannah River Laboratory (SRL) programs, and are finding immediate application in several programs requiring quantitative metallography. It is argued that x-ray computed tomographic imaging, digitally-enhanced ultrasonic testing and acoustic microscopy are three techniques that would enhance not only the research and development efforts at SRL, but also may be applicable in production (for example, in pinch and reclamation welding of tritium reservoirs, and in reactor component inspection) as quality assurance and documentation tools. 21 refs.

  9. Characterization of Savannah River Plant waste glass

    SciTech Connect

    Plodinec, M J

    1985-01-01

    The objective of the glass characterization programs at the Savannah River Laboratory (SRL) is to ensure that glass containing Savannah River Plant high-level waste can be permanently stored in a federal repository, in an environmentally acceptable manner. To accomplish this objective, SRL is carrying out several experimental programs, including: fundamental studies of the reactions between waste glass and water, particularly repository groundwater; experiments in which candidate repository environments are simulated as accurately as possible; burial tests of simulated waste glass in candidate repository geologies; large-scale tests of glass durability; and determination of the effects of process conditions on glass quality. In this paper, the strategy and current status of each of these programs is discussed. The results indicate that waste packages containing SRP waste glass will satisfy emerging regulatory criteria.

  10. An investigation of the role of metacognitive behavior in self-regulated learning when learning a complex science topic with a hypermedia learning environment

    NASA Astrophysics Data System (ADS)

    Binbasaran Tuysuzoglu, Banu

    Studies have shown that learners need to use self-regulated learning (SRL) skills when learning with Hypermedia Learning Environments (HLEs) to reach a conceptual understanding of science. SRL theory suggests that metacognition plays a key role in learning. The aim of this study was to investigate the relationship between metacognitive monitoring (e.g., judgment of learning [JOL]) and metacognitive control and their effects upon learning about the circulatory system with an HLE. I examined the frequencies of learners' use of negative JOL with and without a change in strategy use, which indicates the quality (i.e., static or adaptive) of metacognitive behavior. The results showed that adaptive metacognitive behavior positively related to learning, and static metacognitive behavior negatively related to learning, above and beyond the effect of prior knowledge. Findings provided valuable implications for the benefits of using JOL followed by control over strategy use when learning with HLEs.

  11. Overview and first results from project STABLE (STAble Boundary Layer Experiment)

    SciTech Connect

    Weber, A.H.; Kurzeja, R.J.

    1988-01-01

    The STABLE project (STAble Boundary Layer Experiment) is a multiyear research effort conceived in 1984 by the Savannah River Laboratory (SRL) and planned by several research groups to study turbulence and diffusion in the stable boundary layer (SBL). The program was jointly planned by Department of Energy (DOE) affiliated laboratories and universities including SRL, Atmospheric Turbulence and Diffusion Division (ATDD) of the National Oceanic and Atmospheric Administration (NOAA), Argonne National Laboratory (ANL), North Carolina State University (NCSU), and The Pennsylvania State University. STABLE's goals are to determine the spatial and temporal distribution of turbulent events during the nighttime, to determine the validity of present models and theories in describing the structure and evolution of the SBL, to determine the role of waves and intermittent turbulence in dispersing chemicals, and to determine better parameterization for describing the mean state and intermittent events in the SBL. By taking advantage of special facility, the program seeks to economize effort and cost. 1 ref., 7 figs.

  12. Laboratory testing of West Valley reference 6 glass

    SciTech Connect

    Ebert, W.L.

    1995-07-01

    A series of laboratory tests is being conducted to characterize the corrosion of West Valley reference 6 glass (WV6) and to provide parametric values for modeling its long-term durability. Models require measurement of the corrosion rate in the absence of corrosion products and in fluids that are {open_quotes}saturated{close_quotes} with corrosion products, and the identification of alteration phases. Corrosion rates in dilute and saturated conditions were measured using MCC-1 and PCT tests, respectively. Vapor hydration tests were performed to generate secondary phases. The PCT tests show the WV6 glass to be more durable than SRL EA, SRL 202, and HW-39-1 glasses. Vapor hydration tests show weeksite (a uranyl silicate), a potassium-bearing zeolite, analcime, potassium feldspar, a calcium silicate phase, and lithium phosphate to form as WV6 glass corrodes. Test results are presented and their relevance to long-term performance discussed.

  13. Radiation-Hardened Electronics for Advanced Communications Systems

    NASA Technical Reports Server (NTRS)

    Whitaker, Sterling

    2015-01-01

    Novel approach enables high-speed special-purpose processors Advanced reconfigurable and reprogrammable communication systems will require sub-130-nanometer electronics. Legacy single event upset (SEU) radiation-tolerant circuits are ineffective at speeds greater than 125 megahertz. In Phase I of this project, ICs, LLC, demonstrated new base-level logic circuits that provide SEU immunity for sub-130-nanometer high-speed circuits. In Phase II, the company developed an innovative self-restoring logic (SRL) circuit and a system approach that provides high-speed, SEU-tolerant solutions that are effective for sub-130-nanometer electronics scalable to at least 22-nanometer processes. The SRL system can be used in the design of NASA's next-generation special-purpose processors, especially reconfigurable communication processors.

  14. 76 FR 48125 - Certain Pasta From Italy: Notice of Preliminary Results of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-08

    ... Pastificio dal 1820 SpA (``PAM''), P.A.P. SNC Di Pazienza G.B. & C. (``P.A.P.''), Premiato Pastificio Afeltra S.r.L. (``Afeltra''), Pasta Zara SpA (``Zara''), Pastificio Di Martino Gaetano & F.lli SpA (``Di...''), Pastificio Lucio Garofalo S.p.A. (``Garofalo''), Pastificio Riscossa F.lli Mastromauro S.p.A....

  15. Combustible Cartridge Cases, an Account of the Current Technology and Proposals for Future Development.

    DTIC Science & Technology

    1986-10-01

    basically adopted from slurry preform and pressing techniques. Earlier investigat~ ions (ref. 3) were focussed towards developing techniquzes which...any mechanical treatment need to be carried out in an -5- WSRL-047 1-TR environment that facilitates swelling of the fibres and imbibit ion of the...SRL-0-1-TR Figure HEAD BOX PAPER MCH INE FELTING ANDMOD 1,D ING Figure 3. Schematic diagram for the preparat ion of cartridge cases using the post

  16. Analysis and Compensation For Window Alignment Errors in an Underwater Stereo TV Camera Ranging and Sizing System

    DTIC Science & Technology

    1993-10-01

    0 0 0 - 25- UNCLASSIFIED CŖ SRL-O I 30-TR UNCLASSIFIED ýnf-N2 YN 0,0 FIGURE Al - THREE TRANSMISION MEDIA . NOT WINDOW TL TILT -26- UNCLASSIFIED...21 Appendix A - Theoretical Development of the Optical Effects of Window Misalignment in a three Media System...OF THE OPTICAL EFFECTS OF WINDOW MISALIGNMENT IN A THREE MEDIA 0 SYSTEM For an optical system in water we will show how the deviation in any light ray

  17. Holocene vertical displacement on the central segments of the Wasatch fault zone, Utah

    USGS Publications Warehouse

    DuRoss, C.B.

    2008-01-01

    Compiled per-event vertical-displacement observations from 17 paleoseismic sites along the six central segments of the Wasatch fault zone (WFZ) highlight possible biases and trends in displacement along the fault. The displacement data are consistent with a model of characteristic-type slip, but anomalous and variable displacements indicate that significant natural variability in displacement occurs. When combined into a composite distribution of displacement, 79% of the data fit within a displacement envelope that shows displacement decreasing in a half-ellipse shape from 1.4-3.5 m near the segment centers to 0.6-2.5 m near the ends. Additionally, displacements normalized by the distance from the segment centers to ends decrease from means of 2.0-3.0 m near the segment centers to 1.3-1.9 m near the ends, consistent with characteristic-type slip termination. Although several paleoseismic sites exhibit repeated, similar displacements, the data are sparse and both low-valued (0.5-0.8 m) and high-valued (4.2-4.7 m) outliers suggest complex strain release, possibly resulting from segment interaction and/or noncharacteristic events. Although a global, normal-fault-type surface-rupture-length (SRL) average-displacement regression underpredicts observed WFZ displacements, the largest displacements per segment correspond well with a SRL maximum-displacement regression. This correlation, as well as moderate variability in SRL- and displacement-based moment magnitude, suggests that the anomalous displacements represent the intrinsic variability in characteristic displacement per segment. Thus, minor variations to the characteristic slip model to account for exceptional upper- and lower-bound displacements, e.g., a hybrid characteristic-variable slip model, may be appropriate for the WFZ. Additional paleoseismic data are necessary to address data gaps and biases, to facilitate more robust tests of earthquake-slip models, and to reduce uncertainty in SRL, displacement, and

  18. The relationships between the use of self-regulated learning strategies and depression among medical students: an accelerated prospective cohort study.

    PubMed

    Van Nguyen, Hung; Laohasiriwong, Wongsa; Saengsuwan, Jiamjit; Thinkhamrop, Bandit; Wright, Pamela

    2015-01-01

    We conducted this study to determine the relationships between the use of self-regulated learning strategies (SRL) and depression scores among medical students. An accelerated prospective cohort study among 623 students at a public medical university in Vietnam was carried out during the academic year 2012-2013. The Depression, Anxiety and Stress Scales (21 items) was used to measure depression scores as the primary research outcome, and to measure anxiety and stress scores as the confounding variables. Fourteen SRL subscales including intrinsic/extrinsic goal orientation, task value, self-efficacy for learning, control of learning beliefs, rehearsal, elaboration, organization, critical thinking, meta-cognitive strategies, time and study environment, effort regulation, peer learning, and help seeking were measured using the Motivated Strategies for Learning Questionnaire. Data were collected at two points in time (once each semester). There were 744 responses at the first time (95.88%) and 623 at time two (drop-out rate of 16.26%). The generalized estimating equation was applied to identify any relationships between the use of each SRL subscale and depression scores at time 2, adjusting for the effects of depression at time 1, anxiety, stress, within cluster correlation, and potential demographic covariates. Separate multivariate GEE analysis indicated that all SRL subscales were significantly negatively associated with depression scores, except for extrinsic goal orientation and peer learning. Whereas full multivariate GEE analysis revealed that self-efficacyT1, help-seekingT1, time and study environmentT2 were found to be significantly negatively associated with depressionT2, adjusting for the effects of depressionT1, anxiety, stress, and demographic covariates. The results should be used to provide appropriate support for medical students to reduce depression.

  19. Some Thermophysical Properties of Blood Components and Coolants for Frozen Blood Shipping Containers

    DTIC Science & Technology

    1989-09-01

    AD-A216 099 HSD-TR-89-027 SOME THERMOPHYSICAL PROPERTIES OF BLOOD COMPONENTS AND COOLANTS FOR FROZEN BLOOD SHIPPING CONTAINERS Ettekhar, Jahan G...obsolete SECURITY CLASSIFICATION OF THIS PAGE SUMMARY Thermophysical properties of some coolants and blood components at low temperatures were investigated...Heat of Fusion of Blood Components 33 2 Melting Point and Latent Heat of Fusion of Aqueous Solutions of Ethylene Glycol (Dowtherm SR-l) 33 3 Melting

  20. Interspecific coordination and intraspecific plasticity of fine root traits in North American temperate tree species

    PubMed Central

    Tobner, Cornelia M.; Paquette, Alain; Messier, Christian

    2013-01-01

    Fine roots play an important role in nutrient and water absorption and hence overall tree performance. However, current understanding of the ecological role of belowground traits lags considerably behind those of aboveground traits. In this study, we used data on specific root length (SRL), fine root diameter (D) and branching intensity (BI) of two datasets to examine interspecific trait coordination as well as intraspecific trait variation across ontogenetic stage and soil conditions (i.e., plasticity). The first dataset included saplings of 12 North American temperate tree species grown in monocultures in a common garden experiment to examine interspecific trait coordination. The second dataset included adult and juvenile individuals of four species (present in both datasets) co-occurring in natural forests on contrasting soils (i.e., humid organic, mesic, and xeric podzolic).The three fine root traits investigated were strongly coordinated, with high SRL being related to low D and high BI. Fine root traits and aboveground life-strategies (i.e., relative growth rate) were weakly coordinated and never significant. Intraspecific responses to changes in ontogenetic stage or soil conditions were trait dependent. SRL was significantly higher in juveniles compared to adults for Abies balsamea and Acer rubrum, but did not vary with soil condition. BI did not vary significantly with either ontogeny or soil conditions, while D was generally significantly lower in juveniles and higher in humid organic soils. D also had the least total variability most of which was due to changes in the environment (plasticity). This study brings support for the emerging evidence for interspecific root trait coordination in trees. It also indicates that intraspecific responses to both ontogeny and soil conditions are trait dependent and less concerted. D appears to be a better indicator of environmental change than SRL and BI. PMID:23874347

  1. Application of System and Integration Readiness Levels to Department of Defense Research and Development

    DTIC Science & Technology

    2016-07-01

    and appropriate levels of maturity so that the same metric can be used throughout the acquisition life cycle. Verbal definitions of TRL, MRL, IRL...as opposed to component-centric. The Sauser definition shows each interface with its associated technologies 255Defense ARJ, July 2016, Vol. 23 No...unequal intermediate levels and no verbal definitions akin to those for TRL, IRL, and MRL. This gives SRL a different kind of scale than IRL and TRL

  2. Domain Modeling for Adaptive Training and Education in Support of the US Army Learning Model-Research Outline

    DTIC Science & Technology

    2015-06-01

    teaching tools, current US Army standards for training and education are group instruction and classroom training, also known as “one-to-many...will be largely responsible for managing their own learning. In support of the US Army Learning Model (ALM) and to provide affordable, tailored SRL...and unit modeling, instructional management principles, domain modeling, authoring tools and methods, and evaluation tools and methods. This report

  3. Octave-Band Thresholds for Modeled Reverberant Fields

    NASA Technical Reports Server (NTRS)

    Begault, Durand R.; Wenzel, Elizabeth M.; Tran, Laura L.; Anderson, Mark R.; Trejo, Leonard J. (Technical Monitor)

    1998-01-01

    Auditory thresholds for 10 subjects were obtained for speech stimuli reverberation. The reverberation was produced and manipulated by 3-D audio modeling based on an actual room. The independent variables were octave-band-filtering (bypassed, 0.25 - 2.0 kHz Fc) and reverberation time (0.2- 1.1 sec). An ANOVA revealed significant effects (threshold range: -19 to -35 dB re 60 dB SRL).

  4. Dynamic Multipoint Optimization Application to Corporate Portfolio Management

    DTIC Science & Technology

    2009-04-22

    List of References Austin, M., Zakar, J., York, D., Pettersen, L ., & Duff, E. (2008). A systems approach to the transition of emergent technologies...development • Addition of other variables to SRL model – security readiness 27 1. Austin, M., Zakar, J.,York, D., Pettersen, L ., Duff, E. (2008). A ...Robert Cuellar and Brian J. Sauser 6th Annual Acquisition Research Symposium of the Naval Postgraduate School: Volume I: Defense Acquisition in

  5. Pathogenesis of Salmonellosis: Salmonella Exotoxins

    DTIC Science & Technology

    1982-03-08

    Newport; Sal. 9633 - serotype Newport; and Sal. 9186 - serotype Newport. Salmonella enteritidis serotype typhimurium strain 2000 was obtained from...7054 Table 1I CULTURE MEDIA SURVEY Salmonella enteritidis Salmonella typhimurium serotype Javiana #10016 SRlI Culture Media C H 0 Cell Factor C H 0 Cell...the pediatric bacteriology laboratory of the UTMB Children’s Hospital and previously reported to prs-’uce the heat labile toxin (9). Salmonella

  6. System Maturity and Architecture Assessment Methods, Processes, and Tools

    DTIC Science & Technology

    2012-03-02

    1 For a detailed description of the SRL methodology see Sauser, B., J.E. Ramirez- Marquez , D. Nowicki, A...and Ramirez- Marquez 2009; Magnaye, Sauser et al. 2010). Although there are guidelines and tools to support the assessment process (Nolte, Kennedy...employ these metrics (Tan, Sauser et al. 2011). Graettinger, et al. (Graettinger, Garcia et al. 2002) reports that approaches for readiness level

  7. Worldwide Buoy Technology Survey. Volume 2. Appendix B. Buoy Records. Book 2. Germany - USA

    DTIC Science & Technology

    1991-02-01

    optimization of solor panels and for directing of daymarks. Stability Notes: General Notes Manufacturers: Resinex Offshore Srl Source of Design...performance to pile beacon but cheaper and easier to * install, maintain and move. Stability Notes: General Notes Recommended max. wind speed: 39...maintain and move. Stability Notes: General Notes Recommended max. wind speed: 39 knots; recommended max. wave height: 7 feet. Less vulnerable to

  8. Application-based control of an autonomous mobile robot

    SciTech Connect

    Fisher, J.J.

    1988-01-01

    Industry response to new technology is governed, almost without exception, by the systems available to meet real world needs, not tools which prove the feasibility of the technology. To this end, SRL is developing robust control strategies and tools for potential autonomous vehicle applications on site. This document describes the work packages developed to perform remote tasks and a integrated control environment which allows rapid vehicle applications development and diagnostic capabilities. 5 refs., 7 figs.

  9. Pu-238 fuel form activities, June 1-30, 1980

    SciTech Connect

    Not Available

    1980-07-18

    This monthly report for Pu-238 Fuel Form Activities has two main sections: SRP-PuFF Pu-238 Fuel Form Production Processes and SRL Pu-238 Fuel Form Research and Development. The program status, budget information, and milestone information are discussed in each main section. The Work Breakdown Structures (WBS) for this program is outlined. Only one monthly report per year is processed for EDB.

  10. Specialists Meeting on Impact Damage Tolerance of Structures

    DTIC Science & Technology

    1976-01-01

    damage in metal and fiber- composite structure. III 1 1 IMPACT DAMAGE IN ETIJALS SrlThe impact-darmdge response of metals depends upon many interrelated...established. Il1. 1.2 IMPACT DAMAGE IN FIBER COMPOSITES There has been very little parametric impact-damage testing of fiber composites . Figure 15 shows...type of structural material, and Includes: I. Bullets Impacting metal 2. Bullets or fragments Impacting fiber composites 3. Fragments impacting metal

  11. Arginine residues on the opposite side of the active site stimulate the catalysis of ribosome depurination by ricin A chain by interacting with the P-protein stalk.

    PubMed

    Li, Xiao-Ping; Kahn, Peter C; Kahn, Jennifer Nielsen; Grela, Przemyslaw; Tumer, Nilgun E

    2013-10-18

    Ricin inhibits protein synthesis by depurinating the α-sarcin/ricin loop (SRL). Ricin holotoxin does not inhibit translation unless the disulfide bond between the A (RTA) and B (RTB) subunits is reduced. Ricin holotoxin did not bind ribosomes or depurinate them but could depurinate free RNA. When RTA is separated from RTB, arginine residues located at the interface are exposed to the solvent. Because this positively charged region, but not the active site, is blocked by RTB, we mutated arginine residues at or near the interface of RTB to determine if they are critical for ribosome binding. These variants were structurally similar to wild type RTA but could not bind ribosomes. Their K(m) values and catalytic rates (k(cat)) for an SRL mimic RNA were similar to those of wild type, indicating that their activity was not altered. However, they showed an up to 5-fold increase in K(m) and up to 38-fold decrease in kcat toward ribosomes. These results suggest that the stalk binding stimulates the catalysis of ribosome depurination by RTA. The mutated arginines have side chains behind the active site cleft, indicating that the ribosome binding surface of RTA is on the opposite side of the surface that interacts with the SRL. We propose that stalk binding stimulates the catalysis of ribosome depurination by orienting the active site of RTA toward the SRL and thereby allows docking of the target adenine into the active site. This model may apply to the translation factors that interact with the stalk.

  12. Checkout and start-up of the integrated DWPF (Defense Waste Processing Facility) melter system

    SciTech Connect

    Smith, M.E.; Hutson, N.D.; Miller, D.H.; Morrison, J.; Shah, H.; Shuford, J.A.; Glascock, J.; Wurzinger, F.H.; Zamecnik, J.R.

    1989-11-11

    The Integrated DWPF Melter System (IDMS) is a one-ninth-scale demonstration of the Defense Waste Processing Facility (DWPF) feed preparation, melter, and off-gas systems. The IDMS will be the first engineering-scale melter system at SRL to process mercury and flowsheet levels of halides and sulfates. This report includes a summary of the IDMS program objectives, system and equipment descriptions, and detailed discussions of the system checkout and start-up. 10 refs., 44 figs., 20 tabs.

  13. The common and the distinctive features of the bulged-G motif based on a 1.04 Å resolution RNA structure

    PubMed Central

    Correll, Carl C.; Beneken, Jutta; Plantinga, Matthew J.; Lubbers, Melissa; Chan, Yuen-Ling

    2003-01-01

    Bulged-G motifs are ubiquitous internal RNA loops that provide specific recognition sites for proteins and RNAs. To establish the common and distinctive features of the motif we determined the structures of three variants and compared them with related structures. The variants are 27-nt mimics of the sarcin/ricin loop (SRL) from Escherichia coli 23S ribosomal RNA that is an essential part of the binding site for elongation factors (EFs). The wild-type SRL has now been determined at 1.04 Å resolution, supplementing data obtained before at 1.11 Å and allowing the first calculation of coordinate error for an RNA motif. The other two structures, having a viable (C2658U•G2663A) or a lethal mutation (C2658G• G2663C), were determined at 1.75 and 2.25 Å resolution, respectively. Comparisons reveal that bulged-G motifs have a common hydration and geometry, with flexible junctions at flanking structural elements. Six conserved nucleotides preserve the fold of the motif; the remaining seven to nine vary in sequence and alter contacts in both grooves. Differences between accessible functional groups of the lethal mutation and those of the viable mutation and wild-type SRL may account for the impaired elongation factor binding to ribosomes with the C2658G•G2663C mutation and may underlie the lethal phenotype. PMID:14627814

  14. Time-lens Based Hyperspectral Stimulated Raman Scattering Imaging and Quantitative Spectral Analysis

    PubMed Central

    Wang, Ke; Zhang, Delong; Charan, Kriti; Slipchenko, Mikhail N.; Wang, Ping; Xu, Chris; Cheng, Ji-Xin

    2014-01-01

    We demonstrate a hyperspectral stimulated Raman scattering (SRS) microscope through spectral-transformed excitation. The 1064-nm Stokes pulse was from a synchronized time-lens source, generated through time-domain phase modulation of a continuous wave (CW) laser. The tunable pump pulse was from linear spectral filtering of a femtosecond laser output with an intra-pulse spectral scanning pulse shaper. By electronically modulating the time-lens source at 2.29 MHz, hyperspectral stimulated Raman loss (SRL) images were obtained on a laser-scanning microscope. Using this microscope, DMSO in aqueous solution with a concentration down to 28 mM could be detected at 2 μs time constant. Hyper-spectral SRL images of prostate cancer cells were obtained. Multivariate curve resolution analysis was further applied to decompose the SRL images into concentration maps of CH2 and CH3 bonds. This method offers exciting potential in label-free imaging of live cells using fingerprint Raman bands. Hyperspectral SRS microscopy using a synchronized time-lens source allows mapping of different cellular contents. PMID:23840041

  15. Changes in perceived self-efficacy and attitude toward science and teaching science in elementary school

    NASA Astrophysics Data System (ADS)

    Sullivan, Betsy Ann

    This study was developed in an effort to ascertain if a proposed biological laboratory curriculum as developed and modeled by the instructor would affect the attitudes and perceived self-efficacy towards science, science teaching and ability to learn science of pre-service elementary teachers. Self-regulated learning (SRL) strategies were incorporated as the variation. Attitudinal topics investigated were the perceived ability to learn science and to teach science. Students in one biology for non-science majors. biology laboratory class at the University of Southern Mississippi participated in this case study. The group participated in the modified laboratory section which utilized SRL activities, including reflections on in-class activities. In addition to these activities, the group worked within the state.s elementary science framework to design and implement science lessons. Password protected on-line surveys were used at the beginning and the end of the course to assess the attitudes, perceived self-efficacy and self-regulated learning level of all students. Interviews with participants were conducted as follow up to ascertain long-term impact of the curriculum. Student artifacts, researcher observations and follow up interviews were analyzed to identify any changes in student attitude towards and perceived self-efficacy in science and teaching science. Analysis identified a positive change in students. attitudes and perceived self-efficacy after participation in the modified laboratory section, indicating moderate success of the proposed curriculum based on SRL.

  16. Preparation and physical properties of U{sub 3}O{sub 8}

    SciTech Connect

    Peacock, H.B.

    1983-01-31

    Uranyl nitrate solution from 200-Area processing of spent SRP fuel tubes is now sent to Oak Ridge Y-12 for conversion of uranium metal. However, after implementation of the powder metallurgy (P/M) process, U{sub 3}O{sub 8} powder will be needed at SRP but not uranium metal. U{sub 3}O{sub 8} powder for fabrication and irradiation tests was produced during development of P/M at SRL by firing UO{sub 3}, obtained from Y-12, at 800{degrees}C for 6 hours in a low grade nitrogen atmosphere. The UO{sub 3} powder was produced by denitration of unsulfated uranyl nitrate solution. The stoichiometry, particle size distribution, surface area and density of the Y-12 and SRL powders were measured. A comparison was then made between SRL U{sub 3}O{sub 8} produced at 800{degrees}C in nitrogen and in air and U{sub 3}O{sub 8} produced at Y-12 at other heating temperatures.

  17. Preparation and physical properties of U sub 3 O sub 8

    SciTech Connect

    Peacock, H.B.

    1983-01-31

    Uranyl nitrate solution from 200-Area processing of spent SRP fuel tubes is now sent to Oak Ridge Y-12 for conversion of uranium metal. However, after implementation of the powder metallurgy (P/M) process, U{sub 3}O{sub 8} powder will be needed at SRP but not uranium metal. U{sub 3}O{sub 8} powder for fabrication and irradiation tests was produced during development of P/M at SRL by firing UO{sub 3}, obtained from Y-12, at 800{degrees}C for 6 hours in a low grade nitrogen atmosphere. The UO{sub 3} powder was produced by denitration of unsulfated uranyl nitrate solution. The stoichiometry, particle size distribution, surface area and density of the Y-12 and SRL powders were measured. A comparison was then made between SRL U{sub 3}O{sub 8} produced at 800{degrees}C in nitrogen and in air and U{sub 3}O{sub 8} produced at Y-12 at other heating temperatures.

  18. Comparison of MOVPE grown GaAs, InGaAs and GaAsSb covering layers for different InAs/GaAs quantum dot applications

    NASA Astrophysics Data System (ADS)

    Zíková, Markéta; Hospodková, Alice; Pangrác, Jiří; Oswald, Jiří; Hulicius, Eduard

    2017-04-01

    InAs/GaAs quantum dot (QD) heterostructures with different covering layers (CLs) prepared by MOVPE are compared in this work. The recombination energy of a structure covered only by GaAs depends nonlinearly on CL thickness. Experimental data of photoluminescence (PL) were supported by theoretical simulations. These simulations prove that the strain plays a major role in the structures. InGaAs strain reducing layer (SRL) was studied as well. Due to the strain reduction, the recombination energy is decreased, so the structure has longer PL wavelength. By theoretical simulations it was shown that for high content of In in InGaAs covering layer (approximately 45% and more), the heterostructure is type II, which would normally be unreachable for flat layers. For the structure with GaAsSb SRL, the band alignment is highly dependent on the SRL composition. The type I/type II transition occurs for approximately 15% of Sb; this value also slightly depends on the QD size. All structures were also studied by HRTEM to show different behavior of the CLs on the interface with InAs which highly influences the structure quality.

  19. Results of testing the Grambow rate law for use in HWVP glass durability correlations

    SciTech Connect

    Kuhn, W.L.; Bunnell, L.R.

    1996-03-01

    A theory based on Grambow`s work on hydration of glass as linear function of solution composition was evaluated. Use of Grambow`s linear rate law for correlation of durability with glass composition is not recommended. Dissolution rate of the glass was determined using the rate of release of sodium with an ion selective electrode. This method was tested first applying it to initial dissolution rate of several glasses at several temperatures with zero initial concentration of silicic acid. HW39-2, HW39-4, and SRL-202 from Savannah River were tested; there was significant scatter in the data, with the dissolution rates of HW39 glasses and the SRL glass being comparable within this scatter. The dissolution rate of SRL-202 at 80 C and pH 7 for silicic acid concentrations 0, 25, 50, and 100% saturation, was found to decrease dramatically at only 25% of the saturated silicic acid concentration, which does not conform to the linear theory.

  20. Raman Lidar Measurements of Water Vapor and Cirrus Clouds During the Passage of Hurricane Bonnie

    NASA Technical Reports Server (NTRS)

    Whiteman, D. N.; Evans, K. D.; Demoz, B.; Starr, O C.; Tobin, D.; Feltz, W.; Jedlovec, G. J.; Gutman, S. I.; Schwemmer, G. K.; Cadirola, M.; Melfi, S. H.; Schmidlin, F.

    2000-01-01

    The NASA/GSFC Scanning Raman Lidar (SRL) was stationed on Andros Island in the Bahamas during August - September, 1998 as a part of the third Convection and Moisture Experiment (CAMEX-3) which focussed on hurricane development and tracking. During the period August 21 - 24, hurricane Bonnie passed near Andros Island and influenced the water vapor and cirrus cloud measurements acquired by the SRL. Two drying signatures related to the hurricane were recorded by the SRL and other sensors. Cirrus cloud optical depths (at 351 nm) were also measured during this period. Optical depth values ranged from approximately 0.01 to 1.4. The influence of multiple scattering on these optical depth measurements was studied with the conclusion that the measured values of optical depth are less than the actual value by up to 20%. The UV/lR cirrus cloud optical depth ratio was estimated based on a comparison of lidar and GOES measurements. Simple radiative transfer model calculations compared with GOES satellite brightness temperatures indicate that satellite radiances are significantly affected by the presence of cirrus clouds if IR optical depths are approximately 0.02 or greater. This has implications for satellite cirrus detection requirements.

  1. QM Computations on Complete Nucleic Acids Building Blocks: Analysis of the Sarcin-Ricin RNA Motif Using DFT-D3, HF-3c, PM6-D3H, and MM Approaches.

    PubMed

    Kruse, Holger; Havrila, Marek; Šponer, Jiřı

    2014-06-10

    A set of conformations obtained from explicit solvent molecular dynamics (MD) simulations of the Sarcin-Ricin internal loop (SRL) RNA motif is investigated using quantum mechanical (QM, TPSS-D3/def2-TZVP DFT-D3) and molecular mechanics (MM, AMBER parm99bsc0+χol3 force field) methods. Solvent effects are approximated using implicit solvent methods (COSMO for DFT-D3; GB and PB for MM). Large-scale DFT-D3 optimizations of the full 11-nucleotide motif are compared to MM results and reveal a higher flexibility of DFT-D3 over the MM in the optimization procedure. Conformational energies of the SRL motif expose significant differences in the DFT-D3 and MM energy descriptions that explain difficulties in MD simulations of the SRL motif. The TPSS-D3 data are in excellent agreement with results obtained by the hybrid functionals PW6B95-D3 and M06-2X. Computationally more efficient methods such as PM6-D3H and HF-3c show promising but partly inconsistent results. It is demonstrated that large-scale DFT-D3 computations on complete nucleic acids building blocks are a viable tool to complement the picture obtained from MD simulations and can be used as benchmarks for faster computational methods. Methodological challenges of large-scale QM computations on nucleic acids such as missing solvent-solute interactions and the truncation of the studied systems are discussed.

  2. Long-Lifetime Low-Scatter Neutron Polarization Target

    SciTech Connect

    Dr. Jonathan M. Richardson

    2004-07-09

    Polarized neutrons scattering is an important technology for characterizing magnetic and other materials. Polarized helium three (P-3He) is a novel technology for creating polarized beams and, perhaps more importantly, for the analysis of polarization in highly divergent scattered beams. Analysis of scattered beams requires specialized targets with complex geometries to ensure accurate results. Special materials and handling procedures are required to give the targets a long useful lifetime. In most cases, the targets must be shielded from stray magnetic fields from nearby equipment. SRL has developed and demonstrated hybrid targets made from glass and aluminum. We have also developed and calibrated a low-field NMR system for measuring polarization lifetimes. We have demonstrated that our low-field system is able to measure NMR signals in the presence of conducting (metallic) cell elements. We have also demonstrated a non-magnetic valve that can be used to seal the cells. We feel that these accomplishments in Phase I are sufficient to ensure a successful Phase II program. The commercial market for this technology is solid. There are over nine neutron scattering centers in the US and Canada and over 22 abroad. Currently, the US plans to build a new $1.4B scattering facility called the Spallation Neutron Source (SNS). The technology developed in this project will allow SRL to supply targets to both existing and future facilities. SRL is also involved with the application of P-3He to medical imaging.

  3. Raman Lidar Measurements of Water Vapor and Cirrus Clouds During The Passage of Hurricane Bonnie

    NASA Technical Reports Server (NTRS)

    Whiteman, D. N.; Evans, K. D.; Demoz, B.; Starr, D OC.; Eloranta, E. W.; Tobin, D.; Feltz, W.; Jedlovec, G. J.; Gutman, S. I.; Schwemmer, G. K.; Smith, David E. (Technical Monitor)

    2000-01-01

    The NASA/GSFC Scanning Raman Lidar (SRL) was stationed on Andros Island in the Bahamas during August - September, 1998 as a part of the third Convection and Moisture Experiment (CAMEX-3) which focussed on hurricane development and tracking. During the period August 21 - 24, hurricane Bonnie passed near Andros Island and influenced the water vapor and cirrus cloud measurements acquired by the SRL. Two drying signatures related to the hurricane were recorded by the SRL and other sensors. Cirrus cloud optical depths (at 351 nm) were also measured during this period. Optical depth values ranged from less than 0.01 to 1.5. The influence of multiple scattering on these optical depth measurements was studied. A correction technique is presented which minimizes the influences of multiple scattering and derives information about cirrus cloud optical and physical properties. The UV/IR cirrus cloud optical depth ratio was estimated based on a comparison of lidar and GOES measurements. Simple radiative transfer model calculations compared with GOES satellite brightness temperatures indicate that satellite radiances are significantly affected by the presence of cirrus clouds if IR optical depths are approximately 0.005 or greater. Using the ISCCP detection threshold for cirrus clouds on the GOES data presented here, a high bias of up to 40% in the GOES precipitable water retrieval was found.

  4. Raman Lidar Measurements of Water Vapor and Cirrus Clouds During the Passage of Hurricane Bonnie

    NASA Technical Reports Server (NTRS)

    Whiteman, D. N.; Evans, K. D.; Demoz, B.; Starr, D. OC; Tobin, D.; Feltz, W.; Jedlovec, G. J.; Gutman, S. I.; Schwemmer, G. K.; Cardirola, M.; Melfi, S. H.; Schmidlin, F. J.

    2000-01-01

    The NASA/GSFC Scanning Raman Lidar (SRL) was stationed on Andros Island in the Bahamas during August - September, 1998 as a part of the third Convection and Moisture Experiment (CAMEX-3) which focussed on hurricane development and tracking. During the period August 21 - 24, hurricane Bonnie passed near Andros Island and influenced the water vapor and cirrus cloud measurements acquired by the SRL. Two drying signatures related to the hurricane were recorded by the SRL (Scanning Raman Lidar) and other sensors. Cirrus cloud optical depths (at 351 nm) were also measured during this period. Optical depth values ranged from approximately 0.01 to 1.4. The influence of multiple scattering on these optical depth measurements was studied with the conclusion that the measured values of optical depth are less than the actual value by up to 20% . The UV/IR cirrus cloud optical depth ratio was estimated based on a comparison of lidar and GOES measurements. Simple radiative transfer model calculations compared with GOES satellite brightness temperatures indicate that satellite radiances are significantly affected by the presence of cirrus clouds if IR optical depths are approximately 0.02 or greater. This has implications for satellite cirrus detection requirements.

  5. Achieving effective learning effects in the blended course: a combined approach of online self-regulated learning and collaborative learning with initiation.

    PubMed

    Tsai, Chia-Wen

    2011-09-01

    In many countries, undergraduates are required to take at least one introductory computer course to enhance their computer literacy and computing skills. However, the application software education in Taiwan can hardly be deemed as effective in developing students' practical computing skills. The author applied online self-regulated learning (SRL) and collaborative learning (CL) with initiation in a blended computing course and examined the effects of different combinations on enhancing students' computing skills. Four classes, comprising 221 students, participated in this study. The online SRL and CL with initiation (G1, n = 53), online CL with initiation (G2, n = 68), and online CL without initiation (G3, n = 68) were experimental groups, and the last class, receiving traditional lecture (G4, n = 32), was the control group. The results of this study show that students who received the intervention of online SRL and CL with initiation attained significantly best grades for practical computing skills, whereas those that received the traditional lectures had statistically poorest grades among the four classes. The implications for schools and educators who plan to provide online or blended learning for their students, particularly in computing courses, are also provided in this study.

  6. Pen Branch Fault Program

    SciTech Connect

    Price, V.; Stieve, A.L.; Aadland, R.

    1990-09-28

    Evidence from subsurface mapping and seismic reflection surveys at Savannah River Site (SRS) suggests the presence of a fault which displaces Cretaceous through Tertiary (90--35 million years ago) sediments. This feature has been described and named the Pen Branch fault (PBF) in a recent Savannah River Laboratory (SRL) paper (DP-MS-88-219). Because the fault is located near operating nuclear facilities, public perception and federal regulations require a thorough investigation of the fault to determine whether any seismic hazard exists. A phased program with various elements has been established to investigate the PBF to address the Nuclear Regulatory Commission regulatory guidelines represented in 10 CFR 100 Appendix A. The objective of the PBF program is to fully characterize the nature of the PBF (ESS-SRL-89-395). This report briefly presents current understanding of the Pen Branch fault based on shallow drilling activities completed the fall of 1989 (PBF well series) and subsequent core analyses (SRL-ESS-90-145). The results are preliminary and ongoing: however, investigations indicate that the fault is not capable. In conjunction with the shallow drilling, other activities are planned or in progress. 7 refs., 8 figs., 1 tab.

  7. Evaluation of voice and speech following subtotal reconstructive laryngectomy.

    PubMed

    Pastore, A; Yuceturk, A V; Trevisi, P

    1998-01-01

    Subtotal reconstructive laryngectomy (SRL) can be used to preserve voice in the treatment of selected laryngeal carcinomas. This study was designed to analyze both voice and speech results achieved after SRL in 14 male patients, aged from 48 to 73 years. Surgery was performed between 1983 and 1993. Fundamental frequencies, ranges of frequency, intensities, and intensity ranges were established using an S.I. 80 Philips AAC 600 Audio Active Comparative Language System. Five prolonged vowels and six phonetically balanced sentences were recorded on a tape positioned at a distance of 30 cm from the mouth of each patient during a 3-min recording time. The recorded material was then evaluated by a panel of ten trained listeners who were asked to consider the qualitative parameters and perceptual characteristics of voice and speech according to a scorecard modified from one devised by Voiers and Formigoni. Although a decrease was determined in Fundamental Frequency and intensity of the voice when compared to normal values, the quality and perception of speech were found to be satisfactory. The verbal message could be understood almost exactly by means of constant sonority, correct articulation and improved pneumophonic coordination. These values demonstrate that the new voice achieved after SRL is less sonorous and allows for understandable and socially acceptable speech.

  8. Changes in medical students’ motivation and self-regulated learning: a preliminary study

    PubMed Central

    Jang, Hye W.

    2015-01-01

    Objectives To investigate whether medical students’ motivation and Self-Regulated Learning (SRL) change over time to enhance our understanding of these constructs as dependent variables in medical education. Methods A cohort of first-year students (n=43) at a medical school in South Korea completed a self-report questionnaire on motivation and SRL - the Motivated Strategies for Learning Questionnaire (MSLQ). The same questionnaire was administered to the same cohort in the beginning of Year 2. A Wilcoxon signed-rank test was conducted to determine if changes in participants’ MSLQ scores occurred between in Years 1 and 2. Results Forty-one students completed the questionnaires in both years (95% response rate). Participants’ motivation scores significantly increased, whereas their SRL scores decreased significantly after they went through Year 1. The most notable change in participants’ MLSQ scores was in the increase in their test anxiety. There was a positive association between the participants’ test anxiety and their cognitive strategies use in Year 1, which changed to a negative one in Year 2. Meanwhile, participants’ test anxiety scores and their self-regulation scores became more negatively associated over time. Conclusions Our study shows that even as medical students become more motivated, they actually use fewer self-regulated strategies over time. Our findings highlight the need for change in the medical school’s learning environment to lessen students’ test anxiety to facilitate their use of cognitive and meta-cognitive strategies. PMID:26708325

  9. Escherichia coli mutants deficient in the production of alkaline phosphatase isozymes.

    PubMed Central

    Nakata, A; Yamaguchi, M; Izutani, K; Amemura, M

    1978-01-01

    Escherichia coli K-12 mutants showing an altered isozyme pattern of alkaline phosphatase were isolated. Whereas wild-type strains synthesized all three isozymes in a synthetic medium supplemented with Casamino Acids or arginine but synthesized only isozyme 3 in a medium without supplement, the mutant strains synthesized isozyme 1 and a small amount (if any) of isozyme 2, but no isozyme 3, under all growth conditions. The mutation responsible for the altered isozyme pattern, designated iap, was mapped by P1 transduction in the interval between cysC and srl (at about 58.5 min on the E. coli genetic map). It was cotransducible with cysC and srl at frequencies of 0.54 and 0.08, respectively. The order of the genes in this region was srl-iap-cysC-argA-thyA-lysA. Three more independent mutations were also mapped in the same locus. We purified isozymes 1' and 3' from iap and iap+ strains and analyzed the sequences of four amino acids from the amino terminus of each polypeptide. They were Arg-Thr-Pro-Glu (or Gln) in isozyme 1' and Thr-Pro-Glu (or gln)-Met in isozyme 3', which were identical with those of corresponding isozymes produced by the wild-type phoA+ strain (P.M. Kelley, P.A. Neumann, K. Schriefer, F. Cancedda, M.J. Schlesinger, and R.A. Bradshaw, Biochemistry 12:3499-3503, 1973; M.J. Schlesinger, W. Bloch, and P.M. Kelley, p. 333-342, in Isozymes, Academic Press Inc., 1975). These results indicate that the different mobilities of isozymes 1, 2, and 3 are determined by the presence or absence of amino-terminal arginine residues in polypeptides. Images PMID:348683

  10. Role of a ribosomal RNA phosphate oxygen during the EF-G-triggered GTP hydrolysis.

    PubMed

    Koch, Miriam; Flür, Sara; Kreutz, Christoph; Ennifar, Eric; Micura, Ronald; Polacek, Norbert

    2015-05-19

    Elongation factor-catalyzed GTP hydrolysis is a key reaction during the ribosomal elongation cycle. Recent crystal structures of G proteins, such as elongation factor G (EF-G) bound to the ribosome, as well as many biochemical studies, provide evidence that the direct interaction of translational GTPases (trGTPases) with the sarcin-ricin loop (SRL) of ribosomal RNA (rRNA) is pivotal for hydrolysis. However, the precise mechanism remains elusive and is intensively debated. Based on the close proximity of the phosphate oxygen of A2662 of the SRL to the supposedly catalytic histidine of EF-G (His87), we probed this interaction by an atomic mutagenesis approach. We individually replaced either of the two nonbridging phosphate oxygens at A2662 with a methyl group by the introduction of a methylphosphonate instead of the natural phosphate in fully functional, reconstituted bacterial ribosomes. Our major finding was that only one of the two resulting diastereomers, the SP methylphosphonate, was compatible with efficient GTPase activation on EF-G. The same trend was observed for a second trGTPase, namely EF4 (LepA). In addition, we provide evidence that the negative charge of the A2662 phosphate group must be retained for uncompromised activity in GTP hydrolysis. In summary, our data strongly corroborate that the nonbridging proSP phosphate oxygen at the A2662 of the SRL is critically involved in the activation of GTP hydrolysis. A mechanistic scenario is supported in which positioning of the catalytically active, protonated His87 through electrostatic interactions with the A2662 phosphate group and H-bond networks are key features of ribosome-triggered activation of trGTPases.

  11. Morphological plasticity of ectomycorrhizal short roots in Betula sp and Picea abies forests across climate and forest succession gradients: its role in changing environments.

    PubMed

    Ostonen, Ivika; Rosenvald, Katrin; Helmisaari, Heljä-Sisko; Godbold, Douglas; Parts, Kaarin; Uri, Veiko; Lõhmus, Krista

    2013-01-01

    Morphological plasticity of ectomycorrhizal (EcM) short roots (known also as first and second order roots with primary development) allows trees to adjust their water and nutrient uptake to local environmental conditions. The morphological traits (MTs) of short-living EcM roots, such as specific root length (SRL) and area, root tip frequency per mass unit (RTF), root tissue density, as well as mean diameter, length, and mass of the root tips, are good indicators of acclimation. We investigated the role of EcM root morphological plasticity across the climate gradient (48-68°N) in Norway spruce (Picea abies (L.) Karst) and (53-66°N) birch (Betula pendula Roth., B. pubescens Ehrh.) forests, as well as in primary and secondary successional birch forests assuming higher plasticity of a respective root trait to reflect higher relevance of that characteristic in acclimation process. We hypothesized that although the morphological plasticity of EcM roots is subject to the abiotic and biotic environmental conditions in the changing climate; the tools to achieve the appropriate morphological acclimation are tree species-specific. Long-term (1994-2010) measurements of EcM roots morphology strongly imply that tree species have different acclimation-indicative root traits in response to changing environments. Birch EcM roots acclimated along latitude by changing mostly SRL [plasticity index (PI) = 0.60], while spruce EcM roots became adjusted by modifying RTF (PI = 0.68). Silver birch as a pioneer species must have a broader tolerance to environmental conditions across various environments; however, the mean PI of all MTs did not differ between early-successional birch and late-successional spruce. The differences between species in SRL, and RTF, diameter, and length decreased southward, toward temperate forests with more favorable growth conditions. EcM root traits reflected root-rhizosphere succession across forest succession stages.

  12. Seedling growth and biomass allocation in relation to leaf habit and shade tolerance among 10 temperate tree species.

    PubMed

    Modrzyński, Jerzy; Chmura, Daniel J; Tjoelker, Mark G

    2015-08-01

    Initial growth of germinated seeds is an important life history stage, critical for establishment and succession in forests. Important questions remain regarding the differences among species in early growth potential arising from shade tolerance. In addition, the role of leaf habit in shaping relationships underlying shade tolerance-related differences in seedling growth remains unresolved. In this study we examined variation in morphological and physiological traits among seedlings of 10 forest tree species of the European temperate zone varying in shade tolerance and leaf habit (broadleaved winter-deciduous species vs needle-leaved conifers) during a 10-week period. Seeds were germinated and grown in a controlled environment simulating an intermediate forest understory light environment to resolve species differences in initial growth and biomass allocation. In the high-resource experimental conditions during the study, seedlings increased biomass allocation to roots at the cost of leaf biomass independent of shade tolerance and leaf habit. Strong correlations between relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR), specific leaf area (SLA) and leaf mass fraction (LMF) indicate that physiology and biomass allocation were equally important determinants of RGR as plant structure and leaf morphology among these species. Our findings highlight the importance of seed mass- and seed size-related root morphology (specific root length-SRL) for shade tolerance during early ontogeny. Leaf and plant morphology (SLA, LAR) were more successful in explaining variation among species due to leaf habit than shade tolerance. In both broadleaves and conifers, shade-tolerant species had lower SRL and greater allocation of biomass to stems (stem mass fraction). Light-seeded shade-intolerant species with greater SRL had greater RGR in both leaf habit groups. However, the greatest plant mass was accumulated in the group of heavy-seeded shade

  13. Salt effects on functional traits in model and in economically important Lotus species.

    PubMed

    Uchiya, P; Escaray, F J; Bilenca, D; Pieckenstain, F; Ruiz, O A; Menéndez, A B

    2016-07-01

    A common stress on plants is NaCl-derived soil salinity. Genus Lotus comprises model and economically important species, which have been studied regarding physiological responses to salinity. Leaf area ratio (LAR), root length ratio (RLR) and their components, specific leaf area (SLA) and leaf mass fraction (LMF) and specific root length (SRL) and root mass fraction (RMF) might be affected by high soil salinity. We characterised L. tenuis, L. corniculatus, L. filicaulis, L. creticus, L. burtii and L. japonicus grown under different salt concentrations (0, 50, 100 and 150 mm NaCl) on the basis of SLA, LMF, SRL and RMF using PCA. We also assessed effects of different salt concentrations on LAR and RLR in each species, and explored whether changes in these traits provide fitness benefit. Salinity (150 mm NaCl) increased LAR in L. burtii and L. corniculatus, but not in the remaining species. The highest salt concentration caused a decrease of RLR in L. japonicus Gifu, but not in the remaining species. Changes in LAR and RLR would not be adaptive, according to adaptiveness analysis, with the exception of SLA changes in L. corniculatus. PCA revealed that under favourable conditions plants optimise surfaces for light and nutrient acquisition (SLA and SRL), whereas at higher salt concentrations they favour carbon allocation to leaves and roots (LMF and RMF) in detriment to their surfaces. PCA also showed that L. creticus subjected to saline treatment was distinguished from the remaining Lotus species. We suggest that augmented carbon partitioning to leaves and roots could constitute a salt-alleviating mechanism through toxic ion dilution.

  14. Radionuclide Incorporation in Secondary Crystalline Minerals Resulting from Chemical Weathering of Selected Waste Glasses: Progress Report for Subtask 3d

    SciTech Connect

    SV Mattigod; DI Kaplan; VL LeGore; RD Orr; HT Schaef; JS Young

    1998-10-23

    Experiments were conducted in fiscal year 1998 by Pacific Northwest National Laboratory to evaluate potential incorporation of radionuclides in secondary mineral phases that form from weathering vitrified nuclear waste glasses. These experiments were conducted as part of the Immobilized Low- Activity Waste-Petiormance Assessment (ILAW-PA) to generate data on radionuclide mobilization and transport in a near-field enviromnent of disposed vitrified wastes. An initial experiment was conducted to identify the types of secondary minerals that form from two glass samples of differing compositions, LD6 and SRL202. Chemical weathering of LD6 glass at 90oC in contact with an aliquot of uncontaminated Hanford Site groundwater resulted in the formation of a Crystalline zeolitic mineral, phillipsite. In contrast similar chemical weathering of SRL202 glass at 90"C resulted in the formation of a microcrystalline smectitic mineral, nontronite. A second experiment was conducted at 90"C to assess the degree to which key radionuclides would be sequestered in the structure of secondary crystalline minerals; namely, phillipsite and nontronite. Chemical weathering of LD6 in contact with radionuclide-spiked Hanford Site groundwater indicated that substantial ilactions of the total activities were retained in the phillipsite structure. Similar chemical weathering of SRL202 at 90"C, also in contact with radionuclide-spiked Hanford Site groundwater, showed that significant fractions of the total activities were retained in the nontronite structure. These results have important implications regarding the radionuclide mobilization aspects of the ILAW-PA. Additional studies are required to confkm the results and to develop an improved under- standing of mechanisms of sequestration and attenuated release of radionuclides to help refine certain aspects of their mobilization.

  15. Effects of switchgrass cultivars and intraspecific differences in root structure on soil carbon inputs and accumulation

    SciTech Connect

    Adkins, Jaron; Jastrow, Julie D.; Morris, Geoffrey P.; Six, Johan; de Graaff, Marie-Anne

    2016-01-01

    Switchgrass (Panicum virgatum L), a cellulosic biofuel feedstock, may promote soil C 21 accumulation compared to annual cropping systems by increasing the amount and retention of 22 root-derived soil C inputs. The aim of this study was to assess how different switchgrass 23 cultivars impact soil C inputs and retention, whether these impacts vary with depth, and whether 24 specific root length (SRL) explains these impacts. We collected soil to a depth of 30 cm from six 25 switchgrass cultivars with root systems ranging from high to low SRL. The cultivars (C4 species) 26 were grown for 27 months on soils previously dominated by C3 plants, allowing us to use the 27 natural difference in 13C isotopic signatures between C3 soils and C4 plants to quantify 28 switchgrass-derived C accumulation. The soil was fractionated into coarse particulate organic 29 matter (CPOM), fine particulate organic matter (FPOM), silt, and clay-sized fractions. We 30 measured total C and plant-derived C in all soil fractions across all depths. The study led to two main results: (1) bulk soil C concentrations beneath switchgrass cultivars varied by 40% in the 0-32 10 cm soil depth and by 70% in the 10-20 cm soil depth, and cultivars with high bulk soil C 33 concentrations tended to have relatively high C concentrations in the mineral soil fractions and 34 relatively low C concentrations in the POM fractions; (2) there were significant differences in 35 switchgrass-derived soil C between cultivars at the 0-10 cm depth, where soil C inputs ranged 36 from 1.2 to 3.2 mg C g-1 dry soil. There was also evidence of a positive correlation between SRL 37 and switchgrass-derived C inputs when one outlier data point was removed. These results 38 indicate that switchgrass cultivars differentially impact mechanisms contributing to soil C accumulation.

  16. Ada Compiler Validation Summary Report: Certificate Number: 901120W1.11087 R. R. Software, Inc., IntegrAda 386 5.1.0, North Gate 386/25 PHar Lap/DOS 3.3. (Host and Target)

    DTIC Science & Technology

    1991-08-01

    an arguement causes optimization to be turned partially on or off. The following integer literals are meaningful as an argument to this pragma: 1...compiler will prompt the user after each error to ask if the compilation should be aborted . This option is useful if the user wants to take a coffee...prompts for abort after every error. R The SYM, SRL, and JRL files is put on the E me path as the input file. S Scratch files are put in the current

  17. Effect of temperature gradient in the solution on spiral growth of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{ital x}} bulk single crystals

    SciTech Connect

    Kanamori, Y.; Shiohara, Y.

    1996-11-01

    Bulk single crystals of Y123 are required to clarify the superconductivity phenomena and develop electronic devices using unique superconductive properties. Only the Solute Rich Liquid{endash}Crystal Pulling (SRL-CP) method has succeeded in continuous growth of the Y123 single crystal. In this paper, we investigated the growth of Y123 single crystals under different temperature gradients in the solution in order to understand the growth mechanism of Y123. It was revealed that Y123 single crystals grow with a spiral growth mode, which is in good agreement with the BCF theory. {copyright} {ital 1996 Materials Research Society.}

  18. Techniques for Improving Energy Efficiency at Water Supply Pumping Stations.

    DTIC Science & Technology

    1987-11-01

    LEGENDGD F.’’T ASL S)RL, A, H A’ OR OL ) HENO SH SOLDIERS HOME 7 NH NEA NRENO) Ffiv BRNTAVOIOD vN VAN NESS MC MCMILLAN CLEARWELL .- A, H:r A I FOX HAL [ C...constructed of reinforced concrete and are covered entirely. Including the clearwell storage, the modeled system has a total available storage of 127.7 million...Jurisdiction Location Capacity* Elev. Elev. Low DC WRMA Brentwood Park 25.0 172 135 WAD North McMillan 12.9 159 135 ( clearwells ) South McMillan 20.3 159

  19. Growth potential limits drought morphological plasticity in seedlings from six Eucalyptus provenances.

    PubMed

    Maseda, Pablo H; Fernández, Roberto J

    2016-02-01

    Water stress modifies plant above- vs belowground biomass allocation, i.e., morphological plasticity. It is known that all species and genotypes reduce their growth rate in response to stress, but in the case of water stress it is unclear whether the magnitude of such reduction is linked to the genotype's growth potential, and whether the reduction can be largely attributed to morphological adjustments such as plant allocation and leaf and root anatomy. We subjected seedlings of six seed sources, three from each of Eucalyptus camaldulensis (potentially fast growing) and E. globulus (inherently slow growing), to three experimental water regimes. Biomass, leaf area and root length were measured in a 6-month glasshouse experiment. We then performed functional growth analysis of relative growth rate (RGR), and aboveground (leaf area ratio (LAR), specific leaf area (SLA) and leaf mass ratio (LMR)) and belowground (root length ratio (RLR), specific root length (SRL) and root mass ratio (RMR)) morphological components. Total biomass, root biomass and leaf area were reduced for all Eucalyptus provenances according to drought intensity. All populations exhibited drought plasticity, while those of greater growth potential (RGRmax) had a larger reduction in growth (discounting the effect of size). A positive correlation was observed between drought sensitivity and RGRmax. Aboveground, drought reduced LAR and LMR; under severe drought a negative correlation was found between LMR and RGRmax. Belowground, drought reduced SRL but increased RMR, resulting in no change in RLR. Under severe drought, a negative correlation was found between RLR, SRL and RGRmax. Our evidence strongly supports the classic ecophysiological trade-off between growth potential and drought tolerance for woody seedlings. It also suggests that slow growers would have a low capacity to adjust their morphology. For shoots, this constraint on plasticity was best observed in partition (i.e., LMR) whereas for

  20. Enhancing computing skills of low-achieving students via e-learning: a design experiment of Web-based, problem-based learning and self-regulated learning.

    PubMed

    Lee, Tsang-Hsiung; Shen, Pei-Di; Tsai, Chia-Wen

    2008-08-01

    A design experiment was conducted applying Web-based problem-based learning (PBL), self-regulated learning (SRL), or their combination to help low-achieving students improve their skills of deploying application software in a compulsory course at a vocational school in Taiwan. The effects were encouraging and mostly positive. However, students' inertia to change routines of learning inherited from a culture of taking standard tests found in e-learning practice is quite common. A teacher's awareness of these changes and associated resistance may increase likelihood of e-learning success for future trials. Some modifications of the design are thus suggested for the next round of the experiment.

  1. Convergent evolution led ribosome inactivating proteins to interact with ribosomal stalk.

    PubMed

    Lapadula, Walter J; Sanchez-Puerta, M Virginia; Ayub, Maximiliano Juri

    2012-03-01

    Ribosome-inactivating proteins (RIPs) inhibit protein synthesis by depurinating an adenine on the sarcin-ricin loop (SRL) of the large subunit ribosomal RNA. Several RIPs interact with the C-terminal end of ribosomal stalk P proteins, and this interaction is required for their full activity. In contrast, the activity of Pokeweed Antiviral Protein is not affected by blocking this stalk component. Here, we provide evidence from phylogenetic analyses and sequence alignments suggesting that the interaction with the C-terminal end of P proteins evolved independently in different RIPs by convergent evolution.

  2. Real-Time Implementation of Nonlinear Processing Functions.

    DTIC Science & Technology

    1981-08-01

    release; 8 1 1 06 054 distribution Ualmlted, K REA-IA WOME ~ENTATION FNOLIEA 15CTrJ 7-. 14Srl8 VT TC@SNO NO: RCIPTIENT Ca ANT0 NUMBER5 Malibu CA 93065 epc...nonlinear filtering for trajectory control and guid- ance, "smart" sensing, picture processing, and bandwidth compression. These technologies could benefit ...4. P.K. Watson, J.M. Pollack and J.B. Flannery, "Liquid Crystals and Ordered Fluids, Vol. 3, p. 421, (1977). 5. I.G. Chistyakov and L.K. Vistin, Soy

  3. Potential safety-related incidents with possible applicability to a nuclear fuel reprocessing plant

    SciTech Connect

    Durant, W.S.; Perkins, W.C.; Lee, R.; Stoddard, D.H.

    1982-05-20

    The Safety Technology Group is developing methodology that can be used to assess the risk of operating a plant to reprocess spent nuclear fuel. As an early step in the methodology, a preliminary hazards analysis identifies safety-related incidents. In the absence of appropriate safety features, these incidents could lead to significant consequences and risk to onsite personnel or to the public. This report is a compilation of potential safety-related incidents that have been identified in studies at SRL and in safety analyses of various commercially designed reprocessing plants. It is an expanded revision of the version originally published as DP-1558, Published December 1980.

  4. Supercritical water oxidation technology for DWPF. [Defense Waste Processing Facility (DWPF)

    SciTech Connect

    Carter, J.T.; Gentilucci, J.A.

    1992-02-07

    At the request of Mr. H.L. Brandt and others in the Savannah River Field Office High Level Waste Division office, DWPF, and SRL personnel have reviewed two potential applications for supercritical water oxidation technology in DWPF. The first application would replace the current hydrolysis process by destroying the organic fractions of the precipitated cesium / potassium tetraphenylborate slurry. The second application pertains to liquid benzene destruction. After a thorough evaluation the first application is not recommended. The second is ready to be tested if needed.

  5. Supercritical water oxidation technology for DWPF

    SciTech Connect

    Carter, J.T.; Gentilucci, J.A.

    1992-02-07

    At the request of Mr. H.L. Brandt and others in the Savannah River Field Office High Level Waste Division office, DWPF, and SRL personnel have reviewed two potential applications for supercritical water oxidation technology in DWPF. The first application would replace the current hydrolysis process by destroying the organic fractions of the precipitated cesium / potassium tetraphenylborate slurry. The second application pertains to liquid benzene destruction. After a thorough evaluation the first application is not recommended. The second is ready to be tested if needed.

  6. Evaluation of test authorization #2-1102

    SciTech Connect

    Bridges, N.

    1985-11-15

    The original Test Authorization (TA) is evaluated. A new silver mordenite (Ag Z) cartridge design has been developed and presented to Separations personnel. The future direction for this TA, mutually agreed to by SRP and SRL personnel, is to; document current program status; continue the sampling program to refine the method and gather baseline DF data; finalize new cartridge design and obtain cost and timing estimates for its procurement; complete cost, benefit analysis for silver mordenite; conduct literature search on available technology to divert more iodine to the dissolver off-gas and thus to the iodine reactor.

  7. Performance testing of West Valley Reference 6 glass

    SciTech Connect

    Ebert, W.L.; Bates, J.K.

    1995-06-01

    The chemical durability of West Valley Reference 6 glass is being evaluated by using a suite of laboratory tests which highlight the early, interim, and long-term stages of corrosion. The test results are being used to describe the glass corrosion path and its long-term durability. The long-term durability of the SRL Environmental Assessment glass is being evaluated for comparison. Test results also provide parameter values for an analytical corrosion model that can be used in performance assessments of specific disposal sites.

  8. Operational Changes in a Shared Resource Laboratory with the Use of a Product Lifecycle Management Approach: A Case Study.

    PubMed

    Hexley, Philip; Smith, Victoria; Wall, Samantha

    2016-04-01

    Shared Resource Laboratories (SRLs) provide investigators access to necessary scientific and resource expertise to leverage complex technologies fully for advancing high-quality biomedical research in a cost-effective manner. At the University of Nebraska Medical Center, the Flow Cytometry Research Facility (FCRF) offered access to exceptional technology, but the methods of operation were outdated and unsustainable. Whereas technology has advanced and the institute has expanded, the operations at the facility remained unchanged for 35 yr. To rectify this, at the end of 2013, we took a product lifecycle management approach to affect large operational changes and align the services offered with the SRL goal of education, as well as to provide service to researchers. These disruptive operational changes took over 10 mo to complete and allowed for independent end-user acquisition of flow cytometry data. The results have been monitored for the past 12 mo. The operational changes have had a positive impact on the quality of research, increased investigator-facility interaction, reduced stress of facility staff, and increased overall use of the resources. This product lifecycle management approach to facility operations allowed us to conceive of, design, implement, and monitor effectively the changes at the FCRF. This approach should be considered by SRL management when faced with the need for operationally disruptive measures.

  9. The physical properties and chemical composition of the gas within the free volume of canistered waste forms

    SciTech Connect

    Harbour, J.R.; Miller, T.J.; Whitaker, M.J.

    1990-11-01

    The DWPF must meet Waste Acceptance Preliminary Specifications (WAPS) for acceptance of the DWPF canistered waste forms. A number of these specifications deal with the exclusion of non-wasteglass (or foreign) materials within the canistered waste forms. Those material which are specifically excluded include the following: Free Liquids, Free Gases, other than cover or radiogenic gases, Explosives, Pyrophorics and Combustibles, and Organics. This report documents the results obtained by carrying out an assigned task as described in three task plans. The task plans cover the determination of pressure, gas composition and relative humidity of SRL canistered waste forms; and organic and inorganic analysis of volatilized and condensed species within SRL canistered waste forms. These results provide evidence to demonstrate compliance with these specifications and will be included in the Waste Form Qualification Report (WQR). In all, four canistered waste forms, produced during the Scale Glass Melter (SGM) campaigns, were examined. The internal gas pressure, dewpoint temperature and gas composition were determined for each canistered waste form. The experience gained in these experiments will be used to generate procedures for obtaining the same information on canistered waste forms produced during the Integrated Cold Runs (ICR). 10 refs., 2 figs., 1 tab.

  10. Computational identification of RNA functional determinants by three-dimensional quantitative structure–activity relationships

    PubMed Central

    Blanchet, Marc-Frédérick; St-Onge, Karine; Lisi, Véronique; Robitaille, Julie; Hamel, Sylvie; Major, François

    2014-01-01

    Anti-infection drugs target vital functions of infectious agents, including their ribosome and other essential non-coding RNAs. One of the reasons infectious agents become resistant to drugs is due to mutations that eliminate drug-binding affinity while maintaining vital elements. Identifying these elements is based on the determination of viable and lethal mutants and associated structures. However, determining the structure of enough mutants at high resolution is not always possible. Here, we introduce a new computational method, MC-3DQSAR, to determine the vital elements of target RNA structure from mutagenesis and available high-resolution data. We applied the method to further characterize the structural determinants of the bacterial 23S ribosomal RNA sarcin–ricin loop (SRL), as well as those of the lead-activated and hammerhead ribozymes. The method was accurate in confirming experimentally determined essential structural elements and predicting the viability of new SRL variants, which were either observed in bacteria or validated in bacterial growth assays. Our results indicate that MC-3DQSAR could be used systematically to evaluate the drug-target potentials of any RNA sites using current high-resolution structural data. PMID:25200082

  11. Seedling root responses to soil moisture and the identification of a belowground trait spectrum across three growth forms.

    PubMed

    Larson, Julie E; Funk, Jennifer L

    2016-05-01

    Root trait variation and plasticity could be key factors differentiating plant performance under drought. However, water manipulation and root measurements are rarely coupled empirically across growth forms to identify whether belowground strategies are generalizable across species. We measured seedling root traits across three moisture levels in 18 Mediterranean forbs, grasses, and woody species. Drought increased the root mass fraction (RMF) and decreased the relative proportion of thin roots (indicated by increased root diameters and decreased specific root length (SRL)), rates of root elongation and growth, plant nitrogen uptake, and plant growth. Although responses varied across species, plasticity was not associated with growth form. Woody species differed from forbs and grasses in many traits, but herbaceous groups were similar. Across water treatments, trait correlations suggested a single spectrum of belowground trade-offs related to resource acquisition and plant growth. While effects of SRL and RMF on plant growth shifted with drought, root elongation rate consistently represented this spectrum. We demonstrate that general patterns of root morphology and plasticity are identifiable across diverse species. Root trait measurements should enhance our understanding of belowground strategy and performance across growth forms, but it will be critical to incorporate plasticity and additional aspects of root function into these efforts.

  12. Immobilization of Savannah River high-level wastes in SYNROC: results from performance tests

    SciTech Connect

    Campbell, J.H.; Hoenig, C.L.; Bazan, F.; Ryerson, F.J.; Rozsa, R.B.

    1981-09-25

    Large samples (up to 15cm diameter) of SYNROC D containing simulated Savannah River (SRL) waste sludge have been prepared and performance tested. Waste loadings of 60 to 65 wt% for the SRL composite sludge have been achieved; this corresponds to a waste concentration (volumetric) loading of approximately 2.3 to 2.5 g/cm/sup 3/. A typical SYNROC D sample has a density of about 4.0 g/cm/sup 3/ with less than 0.2% porosity. The compressive and flexural strengths of SYNROC D are 51,200 and 9400 psi, respectively and Young's Modulus is 20.1 x 10/sup 6/ psi by ultrasonic measurement. The quantity of respirable fines (less than 10 ..mu..m) generated during a constant energy density impact (10J/cm/sup 3/) was less than 0.16 wt%. Values for the thermal conductivity (22/sup 0/C) and the thermal expansion coefficient (22 to 950/sup 0/C) were measured to be 1.7 W/m.K and 11 x 10/sup -6/ K/sup -1/, respectively.

  13. Safety rod latch inspection

    SciTech Connect

    Leader, D.R.

    1992-02-01

    During an attempt to raise control rods from the 100 K reactor in December, one rod could not be withdrawn. Subsequent investigation revealed that a small ``button`` in the latch mechanism had broken off of the ``lock plunger`` and was wedged in a position that prevented rod withdrawal. Concern that this failure may have resulted from corrosion or some other metallurgical problem resulted in a request that SRL examine six typical latch mechanisms from the 100 L reactor by use of radiography and metallography. During the examination of the L-Area latches, a failed latch mechanism from the 100 K reactor was added to the investigation. Fourteen latches that had a history of problems were removed from K-Area and sent to SRL for inclusion in this study the week after the original seven assemblies were examined, bringing the total of latch assemblies discussed in this report to twenty one. Results of the examination of the K-Area latch that initiated this study is not included in this report.

  14. Safety rod latch inspection

    SciTech Connect

    Leader, D.R.

    1992-02-01

    During an attempt to raise control rods from the 100 K reactor in December, one rod could not be withdrawn. Subsequent investigation revealed that a small button'' in the latch mechanism had broken off of the lock plunger'' and was wedged in a position that prevented rod withdrawal. Concern that this failure may have resulted from corrosion or some other metallurgical problem resulted in a request that SRL examine six typical latch mechanisms from the 100 L reactor by use of radiography and metallography. During the examination of the L-Area latches, a failed latch mechanism from the 100 K reactor was added to the investigation. Fourteen latches that had a history of problems were removed from K-Area and sent to SRL for inclusion in this study the week after the original seven assemblies were examined, bringing the total of latch assemblies discussed in this report to twenty one. Results of the examination of the K-Area latch that initiated this study is not included in this report.

  15. GaAsSb-capped InAs QD type-II solar cell structures — improvement by composition profiling of layers surrounding QD

    NASA Astrophysics Data System (ADS)

    Hospodková, Alice; Vyskočil, Jan; Zíková, Markéta; Oswald, Jiří; Pangrác, Jiří; Petříček, Otto

    2017-02-01

    Type-II band alignment offers several advantages for proposed intermediate band solar cell structures. We focused on the quantum dot (QD) solar cell structures based on type-II InAs/GaAs QD layers capped with GaAsSb strain reducing layers. The GaAsSb strain reducing layers were prepared with or without graded Sb concentration. Strong enhancement of photocurrent was achieved by adding an InGaAs buffer layer under the type-II QD structure, thanks to improved electron extraction from QDs. For comparison, a structure with GaAs-capped InAs QDs was prepared, too. Properties of all structures are compared and the mechanism of carrier extraction or relaxation is discussed. Gradient of antimony concentration in a strain reducing layer (SRL) significantly improved resulting properties of solar cell structures. It is shown that in a multiple-QD structure with a GaAsSb SRL, electrons and holes have non-intersecting trajectories which prevents carrier recombination and improves the efficiency of solar cell structures. NextNano band structure calculations of different types of structures support our experimental results.

  16. Growth and properties of AIIIBV QD structures for intermediate band solar cells

    NASA Astrophysics Data System (ADS)

    Vyskočil, J.; Gladkov, P.; Petříček, O.; Hospodková, A.; Pangrác, J.

    2015-03-01

    Intermediate band solar cells theoretically offer a promising way to significantly increase cell efficiency compared to a single-junction solar cell. We focused on the preparation of antimony containing materials as a covering of QD layers. In this article we discuss how the concentration gradient of GaAsSb strain reducing layers can influence the resulting optical properties of the solar cell structures. The main principle of the structure is that the absorption of light is achieved at QD excited states with a better overlap of electron and hole wave functions. With fast relaxation of carriers to the ground state, the electrons and holes are quickly spatially separated. Two different composition gradients of GaAsSb SRL were used for the solar cell structure. One or five quantum dot stacks were compared. The maximal PC increased approximately 17 times with increasing number of QD layers from 1 to 5. The highest PC was achieved for sample I5A with increasing concentration of Sb in the SRL, especially in the QD absorption region. The possible explanation is a better carrier separation in this type of structure suppressing the radiative recombination rate in QDs. These results suggest a high application potential of this structure for photovoltaics.

  17. Operational Changes in a Shared Resource Laboratory with the Use of a Product Lifecycle Management Approach: A Case Study

    PubMed Central

    Smith, Victoria; Wall, Samantha

    2016-01-01

    Shared Resource Laboratories (SRLs) provide investigators access to necessary scientific and resource expertise to leverage complex technologies fully for advancing high-quality biomedical research in a cost-effective manner. At the University of Nebraska Medical Center, the Flow Cytometry Research Facility (FCRF) offered access to exceptional technology, but the methods of operation were outdated and unsustainable. Whereas technology has advanced and the institute has expanded, the operations at the facility remained unchanged for 35 yr. To rectify this, at the end of 2013, we took a product lifecycle management approach to affect large operational changes and align the services offered with the SRL goal of education, as well as to provide service to researchers. These disruptive operational changes took over 10 mo to complete and allowed for independent end-user acquisition of flow cytometry data. The results have been monitored for the past 12 mo. The operational changes have had a positive impact on the quality of research, increased investigator-facility interaction, reduced stress of facility staff, and increased overall use of the resources. This product lifecycle management approach to facility operations allowed us to conceive of, design, implement, and monitor effectively the changes at the FCRF. This approach should be considered by SRL management when faced with the need for operationally disruptive measures. PMID:26681929

  18. BelSmile: a biomedical semantic role labeling approach for extracting biological expression language from text

    PubMed Central

    Lai, Po-Ting; Lo, Yu-Yan; Huang, Ming-Siang; Hsiao, Yu-Cheng; Tsai, Richard Tzong-Han

    2016-01-01

    Biological expression language (BEL) is one of the most popular languages to represent the causal and correlative relationships among biological events. Automatically extracting and representing biomedical events using BEL can help biologists quickly survey and understand relevant literature. Recently, many researchers have shown interest in biomedical event extraction. However, the task is still a challenge for current systems because of the complexity of integrating different information extraction tasks such as named entity recognition (NER), named entity normalization (NEN) and relation extraction into a single system. In this study, we introduce our BelSmile system, which uses a semantic-role-labeling (SRL)-based approach to extract the NEs and events for BEL statements. BelSmile combines our previous NER, NEN and SRL systems. We evaluate BelSmile using the BioCreative V BEL task dataset. Our system achieved an F-score of 27.8%, ∼7% higher than the top BioCreative V system. The three main contributions of this study are (i) an effective pipeline approach to extract BEL statements, and (ii) a syntactic-based labeler to extract subject–verb–object tuples. We also implement a web-based version of BelSmile (iii) that is publicly available at iisrserv.csie.ncu.edu.tw/belsmile. PMID:27173520

  19. Disposition of actinides released from high-level waste glass

    SciTech Connect

    Ebert, W.L.; Bates, J.K.; Buck, E.C.; Gong, M.; Wolf, S.F.

    1994-05-01

    A series of static leach tests was conducted using glasses developed for vitrifying tank wastes at the Savannah River Site to monitor the disposition of actinide elements upon corrosion of the glasses. In these tests, glasses produced from SRL 131 and SRL 202 frits were corroded at 90{degrees}C in a tuff groundwater. Tests were conducted using crushed glass at different glass surface area-to-solution volume (S/V) ratios to assess the effect of the S/V on the solution chemistry, the corrosion of the glass, and the disposition of actinide elements. Observations regarding the effects of the S/V on the solution chemistry and the corrosion of the glass matrix have been reported previously. This paper highlights the solution analyses performed to assess how the S/V used in a static leach test affects the disposition of actinide elements between fractions that are suspended or dissolved in the solution, and retained by the altered glass or other materials.

  20. Remediation on off-gas system deposits in a radioactive waste glass melter

    SciTech Connect

    Jantzen, C.M.; Choi, A.S.; Randall, C.T.

    1991-01-01

    Since the early 1980's, research glass melters have been used at the Savannah River Laboratory (SRL) to develop the reference vitrification process for immobilization of high level radioactive waste. One of the operating concerns for these melters has been the pluggage of the off-gas system with solid deposits. Samples of these deposits were analyzed to be mixture of alkali-rich chlorides, sulfates, borates, and fluorides with entrained Fe{sub 2}O{sub 3} spinel, and frit particles. The spatial distribution of these deposits throughout the off-gas system indicates that they form by vapor-phase transport and subsequently condensation. Condensation of the alkali-rich phases cements entrained particulates causing the off-gas line to plug. It is concluded that off-gas system pluggage can be effectively controlled by maintaining the off-gas velocity above 16 m/s, while maintaining the off-gas temperature as high as practical below the glass softening point. This paper summarizes the results of chemical and physical analyses of off-gas deposit samples from various melters at SRL. Recent design changes made to the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) to alleviate the pluggage problem are also discussed.

  1. Remediation on off-gas system deposits in a radioactive waste glass melter

    SciTech Connect

    Jantzen, C.M.; Choi, A.S.; Randall, C.T.

    1991-12-31

    Since the early 1980`s, research glass melters have been used at the Savannah River Laboratory (SRL) to develop the reference vitrification process for immobilization of high level radioactive waste. One of the operating concerns for these melters has been the pluggage of the off-gas system with solid deposits. Samples of these deposits were analyzed to be mixture of alkali-rich chlorides, sulfates, borates, and fluorides with entrained Fe{sub 2}O{sub 3} spinel, and frit particles. The spatial distribution of these deposits throughout the off-gas system indicates that they form by vapor-phase transport and subsequently condensation. Condensation of the alkali-rich phases cements entrained particulates causing the off-gas line to plug. It is concluded that off-gas system pluggage can be effectively controlled by maintaining the off-gas velocity above 16 m/s, while maintaining the off-gas temperature as high as practical below the glass softening point. This paper summarizes the results of chemical and physical analyses of off-gas deposit samples from various melters at SRL. Recent design changes made to the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) to alleviate the pluggage problem are also discussed.

  2. Descriptive epidemiology of detected anthrax outbreaks in wild wood bison (Bison bison athabascae) in northern Canada, 1962-2008.

    PubMed

    Salb, Amanda; Stephen, Craig; Ribble, Carl; Elkin, Brett

    2014-07-01

    We inventoried and assessed historical anthrax outbreak data from 1962-2008 in wild wood bison (Bison bison athabascae) in Wood Buffalo National Park and the Slave River Lowlands (SRL), Northwest Territories, Canada. We compared these results with a 2010 outbreak in the SRL. Anthrax outbreaks have occurred in 12 of the years between 1962 and 2008 in wild wood bison with 1,515 anthrax deaths detected. The average number of carcasses found each outbreak year was 126 (range 1-363), though local averages varied. The numbers of animals found dead per outbreak declined over the past four decades. Outbreaks varied in duration from 16-44 days (average length 25.5 days). The length of an outbreak was not a determinant of the number of dead bison found, but outbreaks starting in July had more deaths than those staring in June. Males were more likely to be detected in an outbreak, outbreaks were likely not random events, and there was no relationship between outbreak size or length and location. Future surveillance activities may benefit from targeting bulls and planning surveillance activities for more than 3 wk after outbreak detection. Coordinating data collecting and recording efforts between jurisdictions may overcome historical challenges in inconsistent record keeping.

  3. NNWSI [Nevada Nuclear Waste Storage Investigation] waste form testing at Argonne National Laboratory; Semiannual report, July--December 1987

    SciTech Connect

    Bates, J.K.; Gerding, T.J.; Ebert, W.L.; Mazer, J.J.; Biwer, B.M.

    1988-07-01

    Tests are ongoing at Argonne National Laboratory to examine the reaction of glass with water under conditions that may exist in the proposed repository at Yucca Mountain, Nevada. Examination of glass reaction using the Unsaturated Test method as applied to simulated defense glass (SRL 165 black frit based) and simulated West Valley glass (ATM-10) is ongoing. The tests on SRL 165 glass have been ongoing for 104 weeks with nonstoichiometric release of Li, Na, B, and actinide elements being observed throughout the test period. The tests on ATM-10 glass have been in progress for 26 weeks and it is too early in the test cycle to assess the glass reaction. The influence of penetrating gamma radiation on the reaction of synthetic nuclear waste glasses in tuff groundwater was also investigated. Modified MCC-1 static leaching experiments were performed under radiation exposures of 1 {times} 10{sup 3} R/h and O R/h at 90{degree}C. The groundwater was acidified by nitrous and nitric acids radiolytically produced in the air. The high bicarbonate ion concentration of the groundwater prevented the pH from dropping below 6.4, however. The glass reaction, as measured by the release of glass species and the thickness of an alteration layer formed on the glass surface, was not measurably affected by radiation. 24 refs., 34 figs., 20 tabs.

  4. Strontium-loaded mineral bone cements as sustained release systems: Compositions, release properties, and effects on human osteoprogenitor cells.

    PubMed

    Tadier, Solène; Bareille, Reine; Siadous, Robin; Marsan, Olivier; Charvillat, Cédric; Cazalbou, Sophie; Amédée, Joelle; Rey, Christian; Combes, Christèle

    2012-02-01

    This study aims to evaluate in vitro the release properties and biological behavior of original compositions of strontium (Sr)-loaded bone mineral cements. Strontium was introduced into vaterite CaCO3 -dicalcium phosphate dihydrate cement via two routes: as SrCO3 in the solid phase (SrS cements), and as SrCl2 dissolved in the liquid phase (SrL cements), leading to different cement compositions after setting. Complementary analytical techniques implemented to thoroughly investigate the release/dissolution mechanism of Sr-loaded cements at pH 7.4 and 37°C during 3 weeks revealed a sustained release of Sr and a centripetal dissolution of the more soluble phase (vaterite) limited by a diffusion process. In all cases, the initial burst of the Ca and Sr release (highest for the SrL cements) that occurred over 48 h did not have a significant effect on the expression of bone markers (alkaline phosphatase, osteocalcin), the levels of which remained overexpressed after 15 days of culture with human osteoprogenitor (HOP) cells. At the same time, proliferation of HOP cells was significantly higher on SrS cements. Interestingly, this study shows that we can optimize the sustained release of Sr(2+) , the cement biodegradation and biological activity by controlling the route of introduction of strontium in the cement paste.

  5. Somatostatin and dopamine receptor regulation of pituitary somatotroph adenomas.

    PubMed

    Ben-Shlomo, Anat; Liu, Ning-Ai; Melmed, Shlomo

    2017-02-01

    Somatostatin and dopamine receptors are expressed in normal and tumoral somatotroph cells. Upon receptor stimulation, somatostatin and the somatostatin receptor ligands octreotide, lanreotide, and pasireotide, and to a lesser extent, dopamine and the dopamine analogs bromocriptine and cabergoline, suppress growth hormone (GH) secretion from a GH-secreting pituitary somatotroph adenoma. Somatostatin and dopamine receptors are Gαi-protein coupled that inhibit adenylate cyclase activity and cAMP production and reduce intracellular calcium concentration and calcium flux oscillations. Although their main action on somatotroph cells is acute inhibition of GH secretion, they also may inhibit GH production and possibly somatotroph proliferation. These receptors have been reported to create complexes that exhibit functions distinct from that of receptor monomers. Somatostatin suppression of GH is mediated mainly by somatostatin receptor subtype 2 and to a lesser extent by SST5. Human somatostatin receptor subtype 5 has also been shown to harbor mutations associated with GH levels, somatotroph tumor behavior, and somatostatin receptor ligand (SRL) responsiveness. Reviewing current knowledge of somatostatin and dopamine receptor expression and signaling in normal and tumoral somatotroph cells offers insights into mechanisms underlying SRL and dopamine agonist effectiveness in patients with acromegaly.

  6. Reactor Materials Program: Mechanical properties of irradiated Types 304 and 304L stainless steel weldment components

    SciTech Connect

    Sindelar, R.L.; Caskey, G.R. Jr.

    1991-12-01

    The vessels (reactor tanks) of the Savannah River Site nuclear production reactors constructed in the 1950`s are comprised of Type 304 stainless steel with Type 308 stainless steel weld filler. Irradiation exposure to the reactor tank sidewalls through reactor operation has caused a change in the mechanical properties of these materials. A database of as-irradiated mechanical properties for site-specific materials and irradiation conditions has been produced for reactor tank structural analyses and to quantify the effects of radiation-induced materials degradation for evaluating reactor service life. The data has been collected from the SRL Reactor Materials Program (RMP) irradiations and testing of archival stainless steel weldment components and from previous SRL programs to measure properties of irradiated reactor Thermal Shield weldments and reactor tank (R-tank) sidewall material. Irradiation programs of the RMP are designed to quantify mechanical properties at tank operating temperatures following irradiation to present and future tank wall maximum exposure conditions. The exposure conditions are characterized in terms of fast neutron fluence (E{sub n} > 0.1 MeV) and displacements per atom (dpa){sup 3}. Tensile properties, Charpy-V notch toughness, and elastic-plastic fracture toughness were measured for base, weld, and weld heat-affected zone (HAZ) weldment components from archival piping specimens following a Screening Irradiation in the University of Buffalo Reactor (UBR) and following a Full-Term Irradiation in the High Flux Isotope Reactor (HFIR).

  7. Reactor Materials Program: Mechanical properties of irradiated Types 304 and 304L stainless steel weldment components

    SciTech Connect

    Sindelar, R.L.; Caskey, G.R. Jr.

    1991-12-01

    The vessels (reactor tanks) of the Savannah River Site nuclear production reactors constructed in the 1950's are comprised of Type 304 stainless steel with Type 308 stainless steel weld filler. Irradiation exposure to the reactor tank sidewalls through reactor operation has caused a change in the mechanical properties of these materials. A database of as-irradiated mechanical properties for site-specific materials and irradiation conditions has been produced for reactor tank structural analyses and to quantify the effects of radiation-induced materials degradation for evaluating reactor service life. The data has been collected from the SRL Reactor Materials Program (RMP) irradiations and testing of archival stainless steel weldment components and from previous SRL programs to measure properties of irradiated reactor Thermal Shield weldments and reactor tank (R-tank) sidewall material. Irradiation programs of the RMP are designed to quantify mechanical properties at tank operating temperatures following irradiation to present and future tank wall maximum exposure conditions. The exposure conditions are characterized in terms of fast neutron fluence (E{sub n} > 0.1 MeV) and displacements per atom (dpa){sup 3}. Tensile properties, Charpy-V notch toughness, and elastic-plastic fracture toughness were measured for base, weld, and weld heat-affected zone (HAZ) weldment components from archival piping specimens following a Screening Irradiation in the University of Buffalo Reactor (UBR) and following a Full-Term Irradiation in the High Flux Isotope Reactor (HFIR).

  8. Leveraging Label-Independent Features for Classification in Sparsely Labeled Networks: An Empirical Study

    NASA Astrophysics Data System (ADS)

    Gallagher, Brian; Eliassi-Rad, Tina

    We address the problem of within-network classification in sparsely labeled networks. Recent work has demonstrated success with statistical relational learning (SRL) and semi-supervised learning (SSL) on such problems. However, both approaches rely on the availability of labeled nodes to infer the values of missing labels. When few labels are available, the performance of these approaches can degrade. In addition, many such approaches are sensitive to the specific set of nodes labeled. So, although average performance may be acceptable, the performance on a specific task may not. We explore a complimentary approach to within-network classification, based on the use of label-independent (LI) features - i.e., features calculated without using the values of class labels. While previous work has made some use of LI features, the effects of these features on classification performance have not been extensively studied. Here, we present an empirical study in order to better understand these effects. Through experiments on several real-world data sets, we show that the use of LI features produces classifiers that are less sensitive to specific label assignments and can lead to performance improvements of over 40% for both SRL- and SSL-based classifiers. We also examine the relative utility of individual LI features; and show that, in many cases, it is a combination of a few diverse network-based structural characteristics that is most informative.

  9. The effects of composition on glass dissolution rates: The application of four models to a data base

    SciTech Connect

    Geldart, R.W.; Kindle, C.H.

    1988-01-01

    Four models have been applied to a data base to relate glass dissolution in distilled water to composition. The data base is used to compare the precisions obtained from the models in fitting actual data. The usefulness of the data base in formulating a model is also demonstrated. Two related models in which the composite or pH-adjusted free energy of hydration of the glass is the correlating parameter are compared with experimental data. In a structural model, the nonbridging oxygen content of the glasses is used to correlate glass dissolution rate to composition. In a model formulated for this report, the cation valence and the oxygen content of the glass are compared with observed dissolution rates. The models were applied to the 28-day normalized silica release at 90/sup 0/C for over 285 glass compositions with surface area to volume ratios of 10 m/sup -1/ (Materials Characterization Center MCC-1 glass durability test using distilled water). These glasses included the nonradioactive analogs of WV205 and SRL-165, as well as SRL-131, PNL 76-68, and a European glass, UK209. Predicted glass dissolution rates show similar fits to the data for all four models. The predictions of the models were also plotted for two subsets of the glasses: waste glasses and Savannah River Laboratory glasses. The model predictions fit the data for these groups much better than they fit the data for the entire set of glasses. 14 refs., 12 figs., 7 tabs.

  10. VapCs of Mycobacterium tuberculosis cleave RNAs essential for translation

    PubMed Central

    Winther, Kristoffer; Tree, Jai J.; Tollervey, David; Gerdes, Kenn

    2016-01-01

    The major human pathogen Mycobacterium tuberculosis can survive in the host organism for decades without causing symptoms. A large cohort of Toxin–Antitoxin (TA) modules contribute to this persistence. Of these, 48 TA modules belong to the vapBC (virulence associated protein) gene family. VapC toxins are PIN domain endonucleases that, in enterobacteria, inhibit translation by site-specific cleavage of initiator tRNA. In contrast, VapC20 of M. tuberculosis inhibits translation by site-specific cleavage of the universally conserved Sarcin-Ricin loop (SRL) in 23S rRNA. Here we identify the cellular targets of 12 VapCs from M. tuberculosis by applying UV-crosslinking and deep sequencing. Remarkably, these VapCs are all endoribonucleases that cleave RNAs essential for decoding at the ribosomal A-site. Eleven VapCs cleave specific tRNAs while one exhibits SRL cleavage activity. These findings suggest that multiple vapBC modules contribute to the survival of M. tuberculosis in its human host by reducing the level of translation. PMID:27599842

  11. Updated study reporting levels (SRLs) for trace-element data collected for the California Groundwater Ambient Monitoring and Assessment (GAMA) Priority Basin Project, October 2009-March 2013

    USGS Publications Warehouse

    Davis, Tracy A.; Olsen, Lisa D.; Fram, Miranda S.; Belitz, Kenneth

    2014-01-01

    evaluated for potential contamination bias by using the same approach developed by Olsen and others (2010). Some data collected by the National Water-Quality Assessment (NAWQA) Program for the Southern California Coastal Drainages study unit were included to supplement the GAMA-PBP data. The detection frequency and upper threshold of potential contamination bias (BD-90/90) were determined from field-blank and equipment-blank data for each trace element. The BD-90/90 is the 90th percentile concentration of potential extrinsic contamination calculated by using the binomial probability distribution for greater than 90 percent confidence. Additionally, data from laboratory blanks and blind blanks analyzed by the National Water Quality Laboratory (NWQL) during water years 2010 through 2013, and compiled by the USGS Branch of Quality Systems (BQS), were considered for each trace element. These results were compared to each constituent’s reporting level to determine whether an SRL was necessary to minimize the potential for detections in the groundwater samples, attributed principally to contamination bias. Results of the evaluation were used to set SRLs for trace-element data for about 1,135 samples of groundwater collected by the GAMA-PBP between October 2009 and March 2013. Ten trace elements analyzed (Sb, As, Be, B, Cd, Li, Se, Ag, Tl, and U) had blank results that did not necessitate establishing SRLs during this review or the review by Olsen and others (2010). Five trace elements analyzed (Al, Ba, Cr, Sr, and V) had blank results that necessitated establishing an SRL during the previous review but did not need an SRL starting October 2009. One trace element (Fe) had field and laboratory-blank results that necessitated keeping the previous SRL (6 micrograms per liter [μg/L]). Two trace elements (Ni and W) had quality-control results that warranted decreasing the previous SRL, and five trace elements (Cu, Pb, Mn, Mo, and Zn) had field, laboratory, or blind blank results

  12. A Comparison of the Functional Traits of Common Reed (Phragmites australis) in Northern China: Aquatic vs. Terrestrial Ecotypes

    PubMed Central

    Li, Liping; Han, Wenxuan; Thevs, Niels; Jia, Xiuhong; Ji, Chengjun; Jin, Dongmei; He, Ping; Schmitt, Armin O.; Cirella, Giuseppe Tommaso; Zerbe, Stefan

    2014-01-01

    Common reed (Phragmites australis (Cav.) Trin. ex Steud.) is distributed widely throughout the world with various ecotypes. This research compares the functional traits and biomass allocation patterns of two contrasting reed ecotypes. Twelve pairs of aquatic and terrestrial reed samples were collected in northern China. Significant differences in functional traits between the two reed ecotypes were observed, while biomass allocation patterns of reed organs did not differ significantly except for at the root. The dry matter content (DMC) in the whole of the reed plant, leaf, root, and rhizome was higher; while the specific leaf area (SLA) and specific root length (SRL) were lower in terrestrial versus aquatic reed. The biomass allocation in organs of the two forms of reed was isometric, only root in the terrestrial habitat increased faster with an increase in the whole plant biomass. It can be affirmed that aquatic and terrestrial reed that adapt to different environments generally has distinct leaf and root functional traits but isometric biomass allocation patterns. This suggests different resource acquisition strategies: (1) aquatic reed grows faster with high SLA and SRL and is more responsive to the environment, while (2) terrestrial reed with high DMC grows slower and is less responsive to the adverse environment (e.g. dry soil conditions). PMID:24586505

  13. Towards quantifying mesoscale flows in the troposphere using Raman lidar and Sondes

    NASA Technical Reports Server (NTRS)

    Demoz, B.; Starr, D.; Evans, K.; Whiteman, D.; Melfi, S.; Turner, D.; Ferrare, R.; Goldsmith, J.; Schwemmer, G.; Cadirola, M.

    1998-01-01

    Water vapor plays an important role in the energetics of the boundary layer processes which in turn play a key role in regulating regional and global climate. It plays a primary role in Earth's hydrological cycle, in radiation balance as a direct absorber of infrared radiation, and in atmospheric circulation as a latent heat energy source, as well as in determining cloud development and atmospheric stability. Water vapor concentration, expressed as a mass mixing ratio (g kg(exp -l)), is conserved in all meteorological processes except condensation and evaporation. This property makes it an ideal choice for studying many of the atmosphere's dynamic features. Raman scattering measurements from lidar also allow retrieval of water vapor mixing ratio profiles at high temporal and vertical resolution. Raman lidars sense water vapor to altitudes not achievable with towers and surface systems, sample the atmosphere at much higher temporal resolution than radiosondes or satellites, and do not require strong vertical gradients or turbulent fluctuations in temperature that is required by acoustic sounders and radars. Analysis of highly-resolved water vapor profiles are used here to characterize two important mesoscale flows: thunderstorm outflows and a cold front passage. The data were obtained at the Atmospheric Radiation Measurement Site (CART) by the groundbased Department of Energy/Sandia National Laboratories lidar (CART Raman lidar or CARL) and Goddard Space Flight Center Scanning Raman Lidar (SRL). A detailed discussion of the SRL and CARL performance during the IOPs is given by others in this meeting.

  14. [Seasonal dynamics of quantitative and morphological traits of poplar fine roots and their differences between successive rotation plantations].

    PubMed

    Wang, Yan-ping; Xu, Tan; Zhu, Wan-rui; Wang, Qi-tong; Liu, Meng-ling; Wang, Hua-tian; Li, Chuan-rong; Dong, Yu-feng

    2016-02-01

    Based on the fine root samples of the first and second generations of poplar (Populus x euramericana ' Neva'), this study examined the response of quantitative and morphological traits of fine roots of different orders and the difference between generations. The results showed that, the quantitative traits of fine roots, such as root length, root surface area and root biomass, presented obvious seasonal variation, and the fine root traits had obvious difference among root orders. The quantitative traits of lower-order fine roots showed significant seasonal difference, and the fine root biomass increased in the growing season and then decreased significantly. The specific root length (SRL) of higher-order roots also showed significant change with season, while the root length density (RLD) and root tissue density (RTD) changed a little. The successive rotation resulted in the significant increase of root length, root biomass, SRL and RLD of 1-2 orders in the growing season. The quantitative traits of first order root significantly positively correlated with soil temperature and moisture, and significantly negatively correlated with the soil organic matter and soil available nitrogen content. However, the quantitative traits of second order root only showed significant correlation with soil nutrient content. The seasonal dynamics of poplar fine roots and the difference between successive rotation plantations implied carbon investment change of poplar to roots. Soil nutrient deficiency induced more carbon investment into roots, and this carbon allocation pattern might affect the aboveground productivity of poplar plantation.

  15. Mobile autonomous robot for radiological surveys

    SciTech Connect

    Dudar, A.M.; Wagner, D.G.; Teese, G.D. )

    1992-01-01

    The robotics development group at the Savannah River Laboratory (SRL) is developing a mobile autonomous robot that performs radiological surveys of potentially contaminated floors. The robot is called SIMON, which stands for Semi-Intelligent Mobile Observing Navigator. Certain areas of SRL are classified as radiologically controlled areas (RCAs). In an RCA, radioactive materials are frequently handled by workers, and thus, the potential for contamination is ever present. Current methods used for floor radiological surveying includes labor-intensive manual scanning or random smearing of certain floor locations. An autonomous robot such as SIMON performs the surveying task in a much more efficient manner and will track down contamination before it is contacted by humans. SIMON scans floors at a speed of 1 in./s and stops and alarms upon encountering contamination. Its environment is well defined, consisting of smooth building floors with wide corridors. The kind of contaminations that SIMON is capable of detecting are alpha and beta-gamma. The contamination levels of interest are low to moderate.

  16. Polarization modulated background-free hyperspectral stimulated Raman scattering microscopy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Houle, Marie-Andrée.; Andreana, Marco; Ridsdale, Andrew; Moffatt, Doug; Lausten, Rune; Légaré, François; Stolow, Albert

    2016-03-01

    Stimulated Raman Scattering (SRS) microscopy is a nonlinear microscopy technique based on Raman vibrational resonances determined by the frequency difference between Pump and Stokes laser pulses. Modulation of one laser beam transfers the modulation to the other, as either a gain in Stokes (SRG) or a loss in Pump power (SRL). SRS microscopy does not exhibit the four-wave mixing nonresonant background characteristic of CARS microscopy. However, other background signals due to two-photon absorption, thermal lensing or cross-phase modulation (XPM) do reduce the detection sensitivity and can distort the hyperspectral scans. Phase sensitive lock-in detection can reduce contributions from two-photon absorption, which is out-of-phase for the SRG case. However, the background signal due to XPM, which can be in-phase with SRS, can reduce the detection sensitivity. We present a novel polarization modulation (PM) scheme in SRS microscopy which greatly reduces the nonresonant XPM background, demonstrated here for the SRL case. Since many Raman vibrational transitions are parallel polarized, the SRS signal is maximum (minimum) when the polarizations of the pump and the Stokes beams are parallel (perpendicular). However, in both parallel and perpendicular Pump-Stokes geometries, XPM is non-zero in many media. Therefore, PM can remove the XPM background without significantly reducing the SRS signal. Our results show that the PM-SRS successfully removes the nonresonant signal due to XPM. High imaging contrast is observed, concomitant with high sensitivity at very low analyte concentrations and undistorted Raman spectra.

  17. Environmental aspects of a tritium oxide release from the Savannah River Site on September 2 and 3, 1984

    SciTech Connect

    Hoel, D.D.; Kurzeja, R.J.; Evans, A.G.

    1990-09-28

    Tritium was released to the atmosphere from the Savannah River Plant during an incident on September 2 and 3, 1984 between 10 PM and 3 AM. During this five hour period, 43,800 Ci of tritium, principally in the form of the oxide (HTO), was released. An additional 14,000, Ci was released during subsequent cleanup operations between September 3 and 7. The total amount released from the incident was 57,800 Ci. The HTO cloud initially moved northward and passed near the towns of New Ellenton and Aiken, SC. Two hours after the release began, the wind shifted and carried the cloud toward Columbia, SC. The cloud moved northeast during the daytime on September 3 over the east-central portion of North Carolina. Environmental sampling teams were dispatched by SRL, SRP, and SCDHEC (South Carolina Department of Health and Environmental Control). SRL collected air and vegetation samples and SRP collected vegetation, water, milk and bioassay samples. SCDHEC collected vegetation, milk, and water samples. The highest activity of HTO measured in vegetation was 501 pCi/mL onsite, 2522 pCi/mL at the plant boundary, and 9859 pCi/mL offsite. These concentrations were approximately 100 times larger than normal values. 13 refs., 7 figs., 10 tabs.

  18. Exploring clinical reasoning in novices: a self-regulated learning microanalytic assessment approach

    PubMed Central

    Artino, Anthony R; Cleary, Timothy J; Dong, Ting; Hemmer, Paul A; Durning, Steven J

    2014-01-01

    Objectives The primary objectives of this study were to examine the regulatory processes of medical students as they completed a diagnostic reasoning task and to examine whether the strategic quality of these regulatory processes were related to short-term and longer-term medical education outcomes. Methods A self-regulated learning (SRL) microanalytic assessment was administered to 71 second-year medical students while they read a clinical case and worked to formulate the most probable diagnosis. Verbal responses to open-ended questions targeting forethought and performance phase processes of a cyclical model of SRL were recorded verbatim and subsequently coded using a framework from prior research. Descriptive statistics and hierarchical linear regression models were used to examine the relationships between the SRL processes and several outcomes. Results Most participants (90%) reported focusing on specific diagnostic reasoning strategies during the task (metacognitive monitoring), but only about one-third of students referenced these strategies (e.g. identifying symptoms, integration) in relation to their task goals and plans for completing the task. After accounting for prior undergraduate achievement and verbal reasoning ability, strategic planning explained significant additional variance in course grade (ΔR2 = 0.15, p < 0.01), second-year grade point average (ΔR2 = 0.14, p < 0.01), United States Medical Licensing Examination Step 1 score (ΔR2 = 0.08, p < 0.05) and National Board of Medical Examiner subject examination score in internal medicine (ΔR2 = 0.10, p < 0.05). Conclusions These findings suggest that most students in the formative stages of learning diagnostic reasoning skills are aware of and think about at least one key diagnostic reasoning process or strategy while solving a clinical case, but a substantially smaller percentage set goals or develop plans that incorporate such strategies. Given that students who developed more strategic plans

  19. Modeling Seismicity Rate Changes in Oklahoma and Arkansas

    NASA Astrophysics Data System (ADS)

    Llenos, A. L.; Michael, A. J.

    2012-12-01

    The rate of M≥3 earthquakes in the central and eastern US increased beginning in 2009, particularly in regions such as Oklahoma and central Arkansas where fluid injection has occurred (Ellsworth et al., SSA abs, 2012; Horton, SRL, 2012). We compare rate changes observed in Oklahoma, which had a low background seismicity rate before 2009, to rate changes observed in central Arkansas, which had swarms prior to the start of wastewater injection (Chiu et al., BSSA, 1984; Horton, SRL, 2012). In both cases, stochastic Epidemic-Type Aftershock Sequence (ETAS) models (Ogata, JASA, 1988) and statistical tests demonstrate that the background rate of independent events and the aftershock productivity must increase in 2009 in order to explain the observed increase in seismicity. Productivity is lower during the earlier tectonic swarms in Arkansas. The change in aftershock productivity may provide a way to distinguish manmade from natural earthquake rate changes and could provide insights into the physical mechanisms of induced seismicity. We fit the ETAS model, which is based on empirical aftershock scaling laws such as Omori's Law and the Gutenberg-Richter magnitude distribution, to a 1973-2011 USGS PDE catalog of M≥3 Oklahoma earthquakes and a 1982-2012 ANSS catalog of M≥2.2 Arkansas earthquakes. To determine whether a rate increase is due to a change in background seismicity rate, aftershock productivity, or some combination of the two, we do the following: 1) fit the model parameters to the data, 2) convert origin times to transformed times (Ogata, JGR, 1992), and 3) use Runs and autocorrelation function tests to test the null hypothesis that the transformed times are drawn from a Poisson distribution with constant rate (as expected when no external processes trigger earthquakes besides a constant tectonic loading rate). In both cases a single set of parameters cannot fit the entire time period, suggesting that significant changes in the underlying process occurred

  20. Relationships between root respiration rate and root morphology, chemistry and anatomy in Larix gmelinii and Fraxinus mandshurica.

    PubMed

    Jia, Shuxia; McLaughlin, Neil B; Gu, Jiacun; Li, Xingpeng; Wang, Zhengquan

    2013-06-01

    Tree roots are highly heterogeneous in form and function. Previous studies revealed that fine root respiration was related to root morphology, tissue nitrogen (N) concentration and temperature, and varied with both soil depth and season. The underlying mechanisms governing the relationship between root respiration and root morphology, chemistry and anatomy along the root branch order have not been addressed. Here, we examined these relationships of the first- to fifth-order roots for near surface roots (0-10 cm) of 22-year-old larch (Larix gmelinii L.) and ash (Fraxinus mandshurica L.) plantations. Root respiration rate at 18 °C was measured by gas phase O2 electrodes across the first five branching order roots (the distal roots numbered as first order) at three times of the year. Root parameters of root diameter, specific root length (SRL), tissue N concentration, total non-structural carbohydrates (starch and soluble sugar) concentration (TNC), cortical thickness and stele diameter were also measured concurrently. With increasing root order, root diameter, TNC and the ratio of root TNC to tissue N concentration increased, while the SRL, tissue N concentration and cortical proportion decreased. Root respiration rate also monotonically decreased with increasing root order in both species. Cortical tissue (including exodermis, cortical parenchyma and endodermis) was present in the first three order roots, and cross sections of the cortex for the first-order root accounted for 68% (larch) and 86% (ash) of the total cross section of the root. Root respiration was closely related to root traits such as diameter, SRL, tissue N concentration, root TNC : tissue N ratio and stele-to-root diameter proportion among the first five orders, which explained up to 81-94% of variation in the rate of root respiration for larch and up to 83-93% for ash. These results suggest that the systematic variations of root respiration rate within tree fine root system are possibly due to the

  1. Savannah River Laboratory Seepage Basins: Waste site assessment report

    SciTech Connect

    Haselow, J.S.; Looney, B.B.; Nichols, R.L.

    1989-09-05

    This Waste Site Assessment for the SRL Seepage Basins is the second in a series of documents being prepared to support development of an appropriate closure plan for these basins. The closure of these basins will be designed to provide protection to human health and the environment and to meet the provisions of the Consent Decree. A Technical Data Summary for these basins has already been submitted as part of the Consent Decree. This Site Assessment Report includes a waste site characterization, and a discussion of closure options for the basins. A closure option is recommended in this report, but details of the recommended closure are not provided in this report since they will be provided in a subsequent closure plan. The closure plan is the third document required under the Consent Decree. 18 refs., 16 figs., 10 tabs.

  2. Geology of the Delta, Escalante, Price, Richfield and Salina 1 deg x 2 deg NTMS quadrangles, Utah

    NASA Astrophysics Data System (ADS)

    Thayer, P. A.

    1981-11-01

    The National Uranium Resource Evaluation (NURE) program was established to evaluate domestic uranium resources in the continental United States and to identify areas favorable for uranium exploration. The Grand Junction Office of the Department of Energy is responsible for administering the program. The Savannah River Laboratory (SRL) is responsible for hydrogeochemical and stream-sediment reconnaissance (HSSR) of 3.9 million sq km (1,500,000 mi(2)) in 37 eastern and western states. This document provides geologic and mineral resources reports for the Delta, Escalante, Price, Richfield, and Salina 1 deg x 2 deg National Topographic Map Series quadrangles, Utah. The purpose of these reports is to provide background geologic and mineral resources information to aid in the interpretation of NURE geochemical reconnaissance data. Except for the Escalante Quadrangle, each report is accompanied by a geologic map and a mineral locality map (Plates 1-8, in pocket).

  3. Process agitator operating problems and equipment failures, F-Canyon Reprocessing Facility

    SciTech Connect

    Durant, W.S.; Starks, J.B.; Low, J.M.; Galloway, W.D.

    1988-09-01

    The Savannah River Laboratory (SRL) maintains a compilation of operating problems and equipment failures that have occurred in the fuel reprocessing areas of the Savannah River Plant (SRP). At present, the data bank contains more than 200,000 entries ranging from minor equipment malfunctions to incidents with the potential for injury or contamination of personnel, or for economic loss. The data bank has been used extensively for a wide variety of purposes, such as failure analyses, trend analyses, and preparation of safety analyses. Typical of the data are problems associated with the F-Canyon process agitators. This report contains a compilation of the agitator operating problems and equipment failures primarily as an aid to organizations with related equipment. Publication of these data was prompted by a number of requests for this information by other Department of Energy (DOE) sites. 4 figs., 4 tabs.

  4. Mitigation alternatives for L Lake. Revision 1

    SciTech Connect

    Moore, D.B.

    1988-11-03

    L-Lake was built in 1985 to receive and cool the thermal effluents from the L-Reactor. The lake was constructed by impounding approximately 7 km of the upper portions of Steel Creek to form a 1000-acre reservoir. Dam construction and reservoir filling were completed in October 1985 and L-Reactor resumed operations at the end of the same month. Since 1985, this system has been developing a biological community comprised of representatives of all trophic levels. The system is impacted by both temperature from the operating reactor and nutrient inputs from the Savannah River ecosystem. A preliminary evaluation of the technical and monetary feasibilities of a number of thermal and/or nutrient mitigation alternatives for the L-Lake ecosystem has been performed by the Ecology Group of SRL/ESD. This report is a summary of the alternatives considered and their applicability.

  5. Retrieval of transuranic waste

    SciTech Connect

    Not Available

    1988-07-19

    Soil removal and drum retrieval equipment are being developed and demonstrated in support of the Transuranic Waste Facility (TWF) program. Accomplishments to date include: Soil removal equipment, a telescoping excavator and high velocity vacuum truck were selected for soil removal; Preliminary demonstrations, the capabilities of both the telescoping excavator and vacuum truck were demonstrated by the vendors; Shielding Lifting Canister, Functional parameters were defined and design is 95% complete; and Full-scale demonstration, SRL test mounds were selected for a full-scale drum retrieval demonstration. Further development will include an integrated full-scale demonstration. Several drums buried in non-radioactive TRU test mounds will be retrieved. Planning for the demonstration is underway. A telescoping excavator is being acquired, the shielded lifting canister will be fabricated and pre-tested, and a vacuum truck will be leased. 5 figs.

  6. Evaluation of liquid-fed ceramic melter scale-up correlations

    SciTech Connect

    Koegler, S.S.; Mitchell, S.J.

    1988-08-01

    This study was conducted to determine the parameters governing factors of scale for liquid-fed ceramic melters (LFCMs) in order to design full-scale melters using smaller-scale melter data. Results of melter experiments conducted at Pacific Northwest Laboratory (PNL) and Savannah River Laboratory (SRL) are presented for two feed compositions and five different liquid-fed ceramic melters. The melter performance data including nominal feed rate and glass melt rate are correlated as a function of melter surface area. Comparisons are made between the actual melt rate data and melt rates predicted by a cold cap heat transfer model. The heat transfer model could be used in scale-up calculations, but insufficient data are available on the cold cap characteristics. Experiments specifically designed to determine heat transfer parameters are needed to further develop the model. 17 refs.

  7. Savannah River Laboratory DOSTOMAN code: a compartmental pathways computer model of contaminant transport

    SciTech Connect

    King, C M; Wilhite, E L; Root, Jr, R W; Fauth, D J; Routt, K R; Emslie, R H; Beckmeyer, R R; Fjeld, R A; Hutto, G A; Vandeven, J A

    1985-01-01

    The Savannah River Laboratory DOSTOMAN code has been used since 1978 for environmental pathway analysis of potential migration of radionuclides and hazardous chemicals. The DOSTOMAN work is reviewed including a summary of historical use of compartmental models, the mathematical basis for the DOSTOMAN code, examples of exact analytical solutions for simple matrices, methods for numerical solution of complex matrices, and mathematical validation/calibration of the SRL code. The review includes the methodology for application to nuclear and hazardous chemical waste disposal, examples of use of the model in contaminant transport and pathway analysis, a user's guide for computer implementation, peer review of the code, and use of DOSTOMAN at other Department of Energy sites. 22 refs., 3 figs.

  8. (Low-level waste disposal facility siting and site characterization)

    SciTech Connect

    Mezga, L.J.; Ketelle, R.H.; Pin, F.G.; Van Hoesen, S.D.

    1985-10-25

    A US team consisting of representatives of Oak Ridge National Laboratory (ORNL), Savannah River Plant (SRP), Savannah river Laboratory (SRL), and the Department of Energy Office of Defense Waste and Byproducts Management participated in the fourth meeting held under the US/French Radioactive Waste Management Agreement between the US Department of Energy and the Commissariat a l'Energie Atomique. This meeting, held at Agence Nationale pour les Gestion des Dechets Radioactifs' (ANDRA's) Headquarters in Paris, was a detailed, technical topical workshop focusing on Low-Level Waste Disposal Facility Siting and Site Characterization.'' The meeting also included a visit to the Centre de la Manche waste management facility operated by ANDRA to discuss and observe the French approach to low-level waste management. The final day of the meeting was spent at the offices of Societe Generale pour les Techniques Nouvelles (SGN) discussing potential areas of future cooperation and exchange. 20 figs.

  9. Interconnecting sensors and people to improve the knowledge and sustainable management in rural and alpine environment: the CIRCE project

    NASA Astrophysics Data System (ADS)

    Cavallo, Eugenio; Biddoccu, Marcella; Bagagiolo, Giorgia; De Marziis, Massimo; Gaia Forni, Emanuela; Alemanno, Laura; Ferraris, Stefano; Canone, Davide; Previati, Maurizio; Turconi, Laura; Arattano, Massimo; Coviello, Velio

    2016-04-01

    Environmental sensor monitoring is continuously developing, both in terms of quantity (i.e. measurement sites), and quality (i.e. technological innovation). Environmental monitoring is carried out by either public or private entities for their own specific purposes, such as scientific research, civil protection, support to industrial and agricultural activities, services for citizens, security, education, and information. However, the acquired dataset could be cross-appealing, hence, being interesting for purposes that diverted from their main intended use. The CIRCE project (Cooperative Internet-of-Data Rural-alpine Community Environment) aimed to gather, manage, use and distribute data obtained from sensors and from people, in a multipurpose approach. The CIRCE project was selected within a call for tender launched by Piedmont Region (in collaboration with CSI Piemonte) in order to improve the digital ecosystem represented by YUCCA, an open source platform oriented to the acquisition, sharing and reuse of data resulting both from real-time and on-demand applications. The partnership of the CIRCE project was made by scientific research bodies (IMAMOTER-CNR, IRPI-CNR, DIST) together with SMEs involved in environmental monitoring and ICT sectors (namely: 3a srl, EnviCons srl, Impresa Verde Cuneo srl, and NetValue srl). Within the project a shared network of agro-meteo-hydrological sensors has been created. Then a platform and its interface for collection, management and distribution of data has been developed. The CIRCE network is currently constituted by a total amount of 171 sensors remotely connected and originally belonging to different networks. They are settled-up in order to monitor and investigate agro-meteo-hydrological processes in different rural and mountain areas of Piedmont Region (NW-Italy), including some very sensitive locations, but difficult to access. Each sensor network differs from each other, in terms of purpose of monitoring, monitored

  10. Comments of the PRA Senior Review Panel on the meeting held December 1--3, 1987

    SciTech Connect

    Sharp, D.A.

    1988-03-21

    This memorandum records the minutes of the PRA Senior Review Panel meeting held at Savannah River Laboratory (SRL) on December 1--3, 1987, and the report on that meeting written subsequently by the panel members. The minutes are contained as Attachment 2 of this memorandum, and the report as Attachment 1. The Panel indicated two principal concerns in their report: (1) that insufficient emphasis is being placed on the reliability data development program, and (2) that excessive detail is being built into the fault trees. These concerns have been addressed in a subsequent meeting with the Panel, held March 2--4, 1988. In addition, the members have been provided with a program document (Reference 1) indicating the extent, the timing, and the limitations of the data analysis effort for the PRA.

  11. A TRMM Rainfall Estimation Method Applicable to Land Areas

    NASA Technical Reports Server (NTRS)

    Prabhakara, C.; Iacovazzi, R., Jr.; Oki, R.; Weinman, J. A.

    1998-01-01

    Utilizing multi-spectral, dual-polarization Special Sensor Microwave Imager (SSM/I) radiometer measurements, we have developed in this study a method to retrieve average rain rate, R(sub f(sub R)), in a mesoscale grid box of 2deg x 3deg over land. The key parameter of this method is the fractional rain area, f(sub R), in that grid box, which is determined with the help of a threshold on the 85 GHz scattering depression 0 deduced from the SSM/I data. In order to demonstrate the usefulness of this method, nine-months of R(sub f(sub R))are retrieved from SSM/I data over three grid boxes in the Northeastern United States. These retrievals are then compared with the corresponding ground-truth-average rain rate, R(sub g), deduced from 15-minute rain gauges. Based on nine months of rain rate retrievals over three grid boxes, we find that R(sub f(sub R)can explain about 64 % of the variance contained in R(sub g). A similar evaluation of the grid-box-average rain rates R(sub GSCAT) and R(sub SRL), given by the NASA/GSCAT and NOAA/SRL rain retrieval algorithms, is performed. This evaluation reveals that R(sub GSCAT) and R(sub SRL) can explain only about 42 % of the variance contained in R(sub g). In our method, a threshold on the 85 GHz scattering depression is used primarily to determine the fractional rain area in a mesoscale grid box. Quantitative information pertaining to the 85 GHz scattering depression in the grid box is disregarded. In the NASA/GSCAT and NOAA/SRL methods on the other hand, this quantitative information is included. Based on the performance of all three methods, we infer that the magnitude of the scattering depression is a poor indicator of rain rate. Furthermore, from maps based on the observations made by SSM/I on land and ocean we find that there is a significant redundancy in the information content of the SSM/I multi-spectral observations. This leads us to infer that observations of SSM/I at 19 and 37 GHz add only marginal information to that

  12. Monte-Carlo simulation studies of the effect of temperature and diameter variation on spin transport in II-VI semiconductor nanowires

    NASA Astrophysics Data System (ADS)

    Chishti, Sabiq; Ghosh, Bahniman; Bishnoi, Bhupesh

    2015-02-01

    We have analyzed the spin transport behaviour of four II-VI semiconductor nanowires by simulating spin polarized transport using a semi-classical Monte-Carlo approach. The different scattering mechanisms considered are acoustic phonon scattering, surface roughness scattering, polar optical phonon scattering, and spin flip scattering. The II-VI materials used in our study are CdS, CdSe, ZnO and ZnS. The spin transport behaviour is first studied by varying the temperature (4-500 K) at a fixed diameter of 10 nm and also by varying the diameter (8-12 nm) at a fixed temperature of 300 K. For II-VI compounds, the dominant mechanism is for spin relaxation; D'yakonovPerel and Elliot Yafet have been actively employed in the first order model to simulate the spin transport. The dependence of the spin relaxation length (SRL) on the diameter and temperature has been analyzed.

  13. Proceedings of the International Congress (12th), Corrosion Control for Low-Cost Reliability, Held in Houston, Texas on September 19-24, 1993. Volume 5B. Corrosion: General Issues

    DTIC Science & Technology

    1993-09-24

    analysed . Corresponding X-ray diffraction patterns (Figures 1 c and l d) show that both the SRL and LRL contain y-FeOOH, with ot-FeOOH and Fe 30 4 in lower...160 .70 5Ni-Cr-Mo-V Steel % 900MPa AIS14340 Steel cy 1240 MPa 71 140 3.5% Na~ l Solution, ZnCotipled -Y6 35 aC olto a R= 0.90, Freq = 0.1 Hz 0 3.5% NaC...0oo000 e 10 69 MPa ArR=O0.90 Freq =5 Hz ~60 0 _0 10- . .. l . . . . . . 1 .. .... I . I ... I . . 10 10s2 103 1o0 Time-To-Failure (hours) 5 (c) Fig

  14. Higher brightness laser diodes with smaller slow axis divergence

    NASA Astrophysics Data System (ADS)

    Sun, Wenyang; Pathak, Rajiv; Campbell, Geoff; Eppich, Henry; Jacob, J. H.; Chin, Aland; Fryer, Jack

    2013-02-01

    The slow axis (SA) divergence of 20% fill-factor, 980nm, laser diodes (LDs) have been investigated under short pulsed (SP) and continuous (CW) operation. By analyzing the data collected under these two modes of operation, one finds that the SA divergence can be separated into two components: an intrinsic divergence and a thermally induced divergence. At low injected current and power, the intrinsic SA divergence is dominant while at high power their magnitudes are approximately equal. The thermal gradient across the broad stripe is negligible under SP operation and, the SA divergence increased at a much slower rate as a function of injected current, thereby increasing the brightness of the LD by 2X. SRL has redesigned microchannel coolers that remove the thermal gradient under CW operation thereby eliminating the thermally induced SA divergence resulting in LDs that are 2X brighter at 300W/bar.

  15. Low Level Laser Therapy: laser radiation absorption in biological tissues

    NASA Astrophysics Data System (ADS)

    Di Giacomo, Paola; Orlando, Stefano; Dell'Ariccia, Marco; Brandimarte, Bruno

    2013-07-01

    In this paper we report the results of an experimental study in which we have measured the transmitted laser radiation through dead biological tissues of various animals (chicken, adult and young bovine, pig) in order to evaluate the maximum thickness through which the power density could still produce a reparative cellular effect. In our experiments we have utilized a pulsed laser IRL1 ISO model (based on an infrared diode GaAs, λ=904 nm) produced by BIOMEDICA s.r.l. commonly used in Low Level Laser Therapy. Some of the laser characteristics have been accurately studied and reported in this paper. The transmission results suggest that even with tissue thicknesses of several centimeters the power density is still sufficient to produce a cell reparative effect.

  16. Direct Detection Doppler Lidar Wind Measurements Obtained During the 2002 International H2O Project (IHOP)

    NASA Technical Reports Server (NTRS)

    Gentry, Bruce; Li, Steven; Chen, Huai-Lin; Comer, Joseph; Mathur, Savyasachee; Bobler, Jeremy

    2005-01-01

    The Goddard Lidar Observatory for Winds (GLOW) is a mobile Doppler lidar system that uses direct detection techniques for profiling winds in the troposphere and lower stratosphere. In May and June of 2002 GLOW was deployed to the Southern Great Plains of the US to participate in the International H2O Project (IHOP). GLOW was located at the Homestead profiling site in the Oklahoma panhandle about 15 km east of the SPOL radar. Several other Goddard lidars, the Scanning Raman Lidar (SRL) and HARLIE, as well as radars and passive instruments were permanently operated from the Homestead site during the IHOP campaign providing a unique cluster of observations. During the IHOP observation period (May 14, 2002 to June 25, 2002) over 240 hours of wind profile measurements were obtained with GLOW. In this paper we will describe the GLOW instrument as it was configured for the IHOP campaign and we will present examples of wind profiles obtained.

  17. Threat detection system for intersection collision avoidance

    NASA Astrophysics Data System (ADS)

    Jocoy, Edward H.; Pierowicz, John A.

    1998-01-01

    Calspan SRL Corporation is currently developing an on- vehicle threat detection system for intersection collision avoidance (ICA) as part of its ICA program with the National Highway Transportation Safety Administration. Crash scenarios were previously defined and an on-board radar sensor was designed. This paper describes recent efforts that include the development of a simulation of a multitarget tracker and collision avoidance algorithm used to predict system performance in a variety of target configurations in the various ICA crash scenarios. In addition, a current headway radar was mounted on the Calspan Instrumented Vehicle and in-traffic data were recorded for two limited crash scenarios. Warning functions were developed through the simulation and applied to the recorded data.

  18. Effect of temperature on mineralization by heterotrophic bacteria

    SciTech Connect

    Tison, D.L.; Pope, D.H.

    1980-03-01

    When pure cultures of the bacteria Pseudomonas fluorescens (a psychrotroph), Escherichia coli (a mesophile), and SRL 261 (a thermophile) were shifted away from temperatures to which they were adapted, the percentage of substrate mineralized increased (percent mineralized = (substrate respired to CO/sub 2/)/(substrate respired to CO/sub 2/ + substrate incorporated into biomass) x 100). The increase in the percent mineralized was larger for larger temperature shifts. Similar responses were observed when natural heterotrophic bacterial populations from sediments of Lake George, N.Y., and a thermophilic algal-bacterial mat community at the Savannah River Plant, Aiken, S.C., were subjected to temperature shifts. These results suggest that an increase in the percent mineralized may be an indication of thermal stress in bacterial populations.

  19. Investigation of a carbon fiber/epoxy prepreg curing behavior for thick composite materials production: An industrial case-study

    NASA Astrophysics Data System (ADS)

    Giorgini, Loris; Mazzocchetti, Laura; Minak, Giangiacomo; Dolcini, Enrico

    2012-07-01

    A case-study is presented, in cooperation with RI-BA Composites srl, where the industrial production of a thick part for primary structural application is analysed. The final product is a bulk carbon fiber reinforced object characterized by great dimensions, with thickness ranging between 10mm and 35mm and obtained by Hand-Lay-Up of prepregs. The study shows that prepregs age along the time required for the process work up. Moreover, the isothermal curing investigation of the prepreg used in the production gives some useful hint for the design of a new thermal curing cycle, in order to avoid exotherm problems along the thickness of the object. The effect of the applied curing cycle on thermal properties of the object are reported.

  20. Research in cosmic and gamma ray astrophysics

    NASA Technical Reports Server (NTRS)

    Stone, Edward C.; Mewaldt, Richard A.; Prince, Thomas A.

    1992-01-01

    Discussed here is research in cosmic ray and gamma ray astrophysics at the Space Radiation Laboratory (SRL) of the California Institute of Technology. The primary activities discussed involve the development of new instrumentation and techniques for future space flight. In many cases these instrumentation developments were tested in balloon flight instruments designed to conduct new investigations in cosmic ray and gamma ray astrophysics. The results of these investigations are briefly summarized. Specific topics include a quantitative investigation of the solar modulation of cosmic ray protons and helium nuclei, a study of cosmic ray positron and electron spectra in interplanetary and interstellar space, the solar modulation of cosmic rays, an investigation of techniques for the measurement and interpretation of cosmic ray isotopic abundances, and a balloon measurement of the isotopic composition of galactic cosmic ray boron, carbon, and nitrogen.

  1. Columbia University flow instability experimental program: Volume 2. Single tube uniformly heated tests -- Part 2: Uncertainty analysis and data

    SciTech Connect

    Dougherty, T.; Maciuca, C.; McAssey, E.V. Jr.; Reddy, D.G.; Yang, B.W.

    1990-05-01

    In June 1988, Savannah River Laboratory requested that the Heat Transfer Research Facility modify the flow excursion program, which had been in progress since November 1987, to include testing of single tubes in vertical down-flow over a range of length to diameter (L/D) ratios of 100 to 500. The impetus for the request was the desire to obtain experimental data as quickly as possible for code development work. In July 1988, HTRF submitted a proposal to SRL indicating that by modifying a facility already under construction the data could be obtained within three to four months. In January 1990, HTFR issued report CU-HTRF-T4, part 1. This report contained the technical discussion of the results from the single tube uniformly heated tests. The present report is part 2 of CU-HTRF-T4 which contains further discussion of the uncertainty analysis and the complete set of data.

  2. Arctic Oceanographic Measurements: 1978-1980,

    DTIC Science & Technology

    1982-06-01

    COUld he comiputed aCCurIat ulI v (:11)l Correct i Program The CII) p rohe conta ins three sens ors: a thupm is tor ,a c onduc1-t iv VI t Cell , anld a...lkE2R’URE lDES.- _____ 0.0 2.0 4.W *-cm 0-E -2w 0w 2- cc-W a -2 w OIO E () mI 6 a 0 S *. B 09,29/9___ ____ Ki<V0/0/003 TA 4 9KBC𔃺 ’ SRL’N! ____C 21L~l...0D ,SI: 2.OC MI w 3.D -- 3. _ _.. -1- - 0 30-O 3 C- l 2 m 26M 7.w 3. IfF P’R OEGTMEr7R (DG lTMEPJ IDE. --- i ----2 c 0 zcc Iac 6 0 D DO 2w 0 .0 WO ac

  3. Analysis of debris vacuumed from K-Reactor tank

    SciTech Connect

    Baumann, E.W.

    1992-01-20

    During the ultrasonic (UT) inspection of K-Reactor tank by the Equipment Engineering Section in the spring of 1990, solid material (termed debris) was seen on the bottom of the tank. When the UT inspection was complete, a specially designed underwater vacuum cleaner was used to collect the accumulation at 17 monitor pin positions. This material was sent to SRL for characterization as an action item of the Reactor Corrosion Mitigation Committee. Acquisition of this debris provided an opportunity to obtain first-hand information about conditions within the tank that affect corrosion conditions and/or moderator chemistry. The purpose of this memorandum is to describe the results of the analyses and the implications of what was found.

  4. Issues in Applying Bio-Inspiration, Cognitive Critical Mass and Developmental-Inspired Principles to Advanced Intelligent Systems

    NASA Astrophysics Data System (ADS)

    Berg-Cross, Gary; Samsonovich, Alexei V.

    This Chapter summarizes ideas presented at the special PerMIS 2008 session on Biological Inspiration for Intelligent Systems. Bio-inspired principles of development and evolution are a special part of the bio-models and principles that can be used to improve intelligent systems and related artifacts. Such principles are not always explicit. They represent an alternative to incremental engineering expansion using new technology to replicate human intelligent capabilities. They are more evident in efforts to replicate and produce a “critical mass” of higher cognitive functions of the human mind or their emergence through cognitive developmental robotics (DR) and self-regulated learning (SRL). DR approaches takes inspiration from natural processes, so that intelligently engineered systems may create solutions to problems in ways similar to what we hypothesize is occurring with biologics in their natural environment. This Chapter discusses how an SRL-based approach to bootstrap a “critical mass” can be assessed by a set of cognitive tests. It also uses a three-level bio-inspired framework to illustrate methodological issues in DR research. The approach stresses the importance of using bio-realistic developmental principles to guide and constrain research. Of particular importance is keeping models and implementation separate to avoid the possible of falling into a Ptolemaic paradigm that may lead to endless tweaking of models. Several of Lungarella's design principles [36] for developmental robotics are discussed as constraints on intelligence as it emerges from an ecologically balanced, three-way interaction between an agents' control systems, physical embodiment, and the external environment. The direction proposed herein is to explore such principles to avoid slavish following of superficial bio-inspiration. Rather we should proceed with a mature and informed developmental approach using developmental principles based on our incremental understanding of how

  5. Frontline Science: Placenta-derived decidual stromal cells alter IL-2R expression and signaling in alloantigen-activated T cells.

    PubMed

    Erkers, Tom; Solders, Martin; Verleng, Lotte; Bergström, Cecilia; Stikvoort, Arwen; Rane, Lalit; Nava, Silvia; Ringdén, Olle; Kaipe, Helen

    2017-03-01

    This study investigated how stromal cells affect the IL-2 pathway in alloantigen-activated T cells. We found that decidual stromal cells (DSCs) from term placentas promoted a high production of IL-2 in cultures with alloantigen-activated T cells. The intensity of expression of cluster of differentiation 25 (CD25; IL-2Rα) on T cells was increased by DSCs, whereas the frequency and intensity of expression of the signaling subunits CD122 (IL-2Rβ) and CD132 (IL-2Rγc) were reduced. Consequently, uptake of IL-2 and STAT5 phosphorylation (pSTAT5) was abrogated. DSCs also decreased the proportion of pSTAT5(+) T cells in response to IL-15, which also use CD122 for signaling. Addition of DSCs to the allogeneic cultures did not increase the expression of programmed death 1 (PD-1) or CD95, indicating that they did not promote T cell exhaustion. However, exogenous recombinant (r)IL-2 in similar concentrations in the same setting increased the expression of CD95 and down-regulated CD122 in T cells. The antiproliferative effect of sirolimus (SRL) and cyclosporine A (CsA), which target the IL-2 signaling pathway, was diminished by DSCs in vitro. To conclude, DSCs affect IL-2 production and IL-2R expression and signaling, which may contribute to the stromal cell-mediated immune modulation and phenotype shift seen in activated T cells. Altered proliferation in cultures when combining DSCs and SRL or CsA may be of clinical importance, as stromal cells are used in trials for acute inflammation and are often used in combination with conventional immunosuppressive therapies.

  6. Mode beating and heterodyning of monolithically integrated semiconductor ring lasers

    NASA Astrophysics Data System (ADS)

    Liu, Chiyu

    Monolithically integrated semiconductor ring lasers (SRLs) are attractive optical sources for optoelectronic integrated circuits (OEICs) because they do not require any feedback elements, do not have parts exposed to external ambient, and can operate in a traveling-wave mode. They are promising candidates for wavelength filtering, unidirectional traveling-wave operation, and multiplexing/demultiplexing applications. Ring lasers can also be used as ultrashort pulse generators using various mode-locking schemes and as active gyro components. However, the SRL is a very complicated dynamic system, which requires more investigations to understand the performance regarding details of the design and fabrication. As a part of NASA-supported project "Monolithically Integrated Semiconductor Ring Laser Gyro for Space Applications", this dissertation research was focused on design and characterization of a novel monolithically integrated rotation sensor based on two large-size independent SRLs. Numerical modeling based on the beam propagation method (BPM) was used to design the fabrication parameters for the single-mode ridge-waveguide ring cavity and directional coupler waveguides. The mode internal coupling in single lateral-mode laser diodes with InGaAs/GaAs material system was investigated by optical experiments and numerical modeling. To gain the understanding of the SRL performance, optical and electrical characterization was performed on fabricated SRLs. Particular emphasis was placed on the study of optical and radio frequency (RF) beating spectra of longitudinal modes of ring lasers. RF measurements provide high accuracy in the diagnosis of laser oscillation parameters by purely electronic means, particularly in the measurement of the group index and its dependence on current and temperature. Theoretical analysis based on the effective index method provides good agreement between the experimental data and numerical calculations. Finally, optical heterodyning spectra

  7. /sup 238/Pu fuel form processes. Quarterly report, April-June 1982

    SciTech Connect

    j

    1982-11-01

    Progress in studies of /sup 238/Pu fuel form processes is reported. Analytical studies of weld-quench cracking in DOP-26 iridium alloy-clad vent sets in General Purpose Heat Sources (GPHS) showed that weld-quench cracking is much more severe in MER alloy than in LR and NR alloys. Spark source mass spectrometry indicated that areas in DOP-26 alloy with severe weld-quench cracking have high thorium inhomogeneity. Secondary ion mass spectrometry revealed differences in LR and MR alloys that may be related to their dissimilar susceptibilities for weld-quench cracking. Impact ductility tests showed that welds in DOP-26 alloy clad vent sets made using parameters similar to PuFF production welding had high elongations. Decontamination of encapsulated GPHS pellets in PuFF was demonstrated using a solution of 3.5 M HNO/sub 3/ + 6.4 M HF which is capable of reducing transferable contamination below the specified 10/sup 3/ dpm upper limit in <30 minutes at a bath temperature of 80/sup 0/C using ultrasonic cleaning. Decontamination vessels were constructed to trap and condense acid vapors during decontamination. Impact and metallographic data showed that although the micro and macrostructures between LANL and SRL pellets have large differences, the difference in impact response between these two types of pellets is not correspondingly large. Both types of pellets have impacted successfully. The micro and macrostructures of SRP pellets made with either low fired shards sintered in Ar/5%O/sub 2/ or Ar are intermediate between those of the LANL and SRL pellets. Therefore, either type of SRP pellet should impact successfully.

  8. Effects of spatiotemporal variation of soil salinity on fine root distribution in different plant configuration modes in new reclamation coastal saline field.

    PubMed

    Jiang, Hong; Du, Hongyu; Bai, Yingying; Hu, Yue; Rao, Yingfu; Chen, Chong; Cai, Yongli

    2016-04-01

    In order to study the effects of salinity on plant fine roots, we considered three different plant configuration modes (tree stand model (TSM), shrub stand model (SSM), and tree-shrub stand model (TSSM)). Soil samples were collected with the method of soil drilling. Significant differences of electrical conductivity (EC) in the soil depth of 0-60 cm were observed among the three modes (p < 0.05). In the above three modes, the variation of soil salinity among various soil layers and monthly variation of soil salinity were the highest in SSM and reached 2.30 and 2.23 mS/cm (EC1:5), respectively. Due to the effect of salinity, fine root biomass (FRB) showed significant differences in different soil depths (p < 0.05). More than 60% of FRB was concentrated in the soil depth above 30 cm. FRB showed exponential decline with soil depth (p < 0.05). FRB showed spatial heterogeneity in the 40-cm soil depth. In the above three modes, compared with FRB, specific root length (SRL) and fine root length density (FRLD) showed the similar changing trend. Fine roots showed significant seasonal differences among different modes (p < 0.05). FRB showed the bimodal variation and was the highest in July. However, we found that the high content of salts had obvious inhibitory effect on the distribution of FRB. Therefore, the salinity should be below 1.5 mS/cm, which was suitable for the growth of plant roots. Among the three modes, TSSM had the highest FRB, SRL, and FRLD and no obvious soil salt accumulation was observed. The results indicated that fine root biomass was affected by high salt and that TSSM had the strong effects of salt suppression and control. In our study, TSSM may be the optimal configuration mode for salt suppression and control in saline soil.

  9. The A1 Subunit of Shiga Toxin 2 Has Higher Affinity for Ribosomes and Higher Catalytic Activity than the A1 Subunit of Shiga Toxin 1

    PubMed Central

    Basu, Debaleena; Li, Xiao-Ping; Kahn, Jennifer N.; May, Kerrie L.; Kahn, Peter C.

    2015-01-01

    Shiga toxin (Stx)-producing Escherichia coli (STEC) infections can lead to life-threatening complications, including hemorrhagic colitis (HC) and hemolytic-uremic syndrome (HUS), which is the most common cause of acute renal failure in children in the United States. Stx1 and Stx2 are AB5 toxins consisting of an enzymatically active A subunit associated with a pentamer of receptor binding B subunits. Epidemiological evidence suggests that Stx2-producing E. coli strains are more frequently associated with HUS than Stx1-producing strains. Several studies suggest that the B subunit plays a role in mediating toxicity. However, the role of the A subunits in the increased potency of Stx2 has not been fully investigated. Here, using purified A1 subunits, we show that Stx2A1 has a higher affinity for yeast and mammalian ribosomes than Stx1A1. Biacore analysis indicated that Stx2A1 has faster association and dissociation with ribosomes than Stx1A1. Analysis of ribosome depurination kinetics demonstrated that Stx2A1 depurinates yeast and mammalian ribosomes and an RNA stem-loop mimic of the sarcin/ricin loop (SRL) at a higher catalytic rate and is a more efficient enzyme than Stx1A1. Stx2A1 depurinated ribosomes at a higher level in vivo and was more cytotoxic than Stx1A1 in Saccharomyces cerevisiae. Stx2A1 depurinated ribosomes and inhibited translation at a significantly higher level than Stx1A1 in human cells. These results provide the first direct evidence that the higher affinity for ribosomes in combination with higher catalytic activity toward the SRL allows Stx2A1 to depurinate ribosomes, inhibit translation, and exhibit cytotoxicity at a significantly higher level than Stx1A1. PMID:26483409

  10. QTL Mapping of Agronomic Waterlogging Tolerance Using Recombinant Inbred Lines Derived from Tropical Maize (Zea mays L) Germplasm

    PubMed Central

    Zaidi, Pervez Haider; Rashid, Zerka; Vinayan, Madhumal Thayil; Almeida, Gustavo Dias; Phagna, Ramesh Kumar; Babu, Raman

    2015-01-01

    Waterlogging is an important abiotic stress constraint that causes significant yield losses in maize grown throughout south and south-east Asia due to erratic rainfall patterns. The most economic option to offset the damage caused by waterlogging is to genetically incorporate tolerance in cultivars that are grown widely in the target agro-ecologies. We assessed the genetic variation in a population of recombinant inbred lines (RILs) derived from crossing a waterlogging tolerant line (CAWL-46-3-1) to an elite but sensitive line (CML311-2-1-3) and observed significant range of variation for grain yield (GY) under waterlogging stress along with a number of other secondary traits such as brace roots (BR), chlorophyll content (SPAD), % stem and root lodging (S&RL) among the RILs. Significant positive correlation of GY with BR and SPAD and negative correlation with S&RL indicated the potential use of these secondary traits in selection indices under waterlogged conditions. RILs were genotyped with 331 polymorphic single nucleotide polymorphism (SNP) markers using KASP (Kompetitive Allele Specific PCR) Platform. QTL mapping revealed five QTL on chromosomes 1, 3, 5, 7 and 10, which together explained approximately 30% of phenotypic variance for GY based on evaluation of RIL families under waterlogged conditions, with effects ranging from 520 to 640 kg/ha for individual genomic regions. 13 QTL were identified for various secondary traits associated with waterlogging tolerance, each individually explaining from 3 to 14% of phenotypic variance. Of the 22 candidate genes with known functional domains identified within the physical intervals delimited by the flanking markers of the QTL influencing GY and other secondary traits, six have previously been demonstrated to be associated with anaerobic responses in either maize or other model species. A pair of flanking SNP markers has been identified for each of the QTL and high throughput marker assays were developed to facilitate

  11. Cardiorespiratory Responses to Stationary Running in Water and on Land

    PubMed Central

    Kruel, Luiz Fernando M.; Beilke, Débora D.; Kanitz, Ana C.; Alberton, Cristine L.; Antunes, Amanda H.; Pantoja, Patrícia D.; da Silva, Eduardo M.; Pinto, Stephanie S.

    2013-01-01

    The aim of the study was to compare maximal and submaximal cardiorespiratory responses between progressive tests on a treadmill on land (TRE), and stationary running on land (SRL) and in water (SRW), while also comparing two methods of determining the second turn point (ST) (ventilatory curve and heart rate deflection point). The study sample consisted of nine active women (23 ± 1.94 years) that performed three maximal protocols in separate days. Heart rate (HR) and oxygen uptake (VO2) were measured in all sessions. The data were analyzed using repeated-measures ANOVA and two-way repeated measures ANOVA with post-hoc Bonferroni test. Greater values of maximal HR (HRmax) and HR at ST (HRST) were observed during exercise performed on TRE and during the SRL, compared to the SRW (p < 0.05). The results for maximal VO2 (VO2max) and VO2 at ST (VO2ST) showed greater and significant values on TRE compared to STL and STW (p < 0.05). Furthermore, the HR and VO2 corresponding to the ST showed similar values between the two methods. Thus, the main conclusion of the present study was that the HR deflection point seems to be a simple and practical alternative method for determining the ST in all protocols analyzed. Key Points The maximal and submaximal (second turn point) oxygen uptake were influenced by the type of exercise, as these responses were similar in both water-based and land-based stationary running protocols and different from those obtained during the treadmill running, that presented greater values compared with both stationary running protocols. The heart rate deflection point can be used for determining the second turn point during stationary running test in aquatic environment. Caution is necessary in the interpretation of the application of the heart rate deflection point in water aerobics exercises because we analyzed only young women performing one water-based exercise. PMID:24149170

  12. Removal of cesium from aluminum decladding wastes generated in irradiated target processing using a fixed-bed column of resorcinol-formaldehyde resin

    SciTech Connect

    Brunson, R.R.; Williams, D.F.; Bond, W.D.; Benker, D.E.; Chattin, F.R.; Collins, E.D.

    1994-09-01

    The removal of cesium (Cs) from a low-level liquid waste (LLLW) with a cation-exchange column was demonstrated using a resorcinol-formaldehyde (RF) resin. The RF resin was developed at the Westinghouse Savannah River Laboratory (SRL) and is highly specific for the removal of Cs from an alkaline waste of high sodium content. It was determined that the RF resin would be suitable for removing Cs, the largest gamma radiation contributor, from the LLLW generated at the Radiochemical Engineering Development Center located at the Oak Ridge National Laboratory. Presently, the disposal of the LLLW is limited due to the amount of Cs contained in the waste. Cesium removal from the waste solution offers immediate benefits by conserving valuable tank space and would allow cask shipments of the treated waste should the present Laboratory pipelines become unavailable in the future. Preliminary laboratory tests of the RF resins, supplied from two different sources, were used to design a full-scale cation-exchange column for the removal of Cs from a Mark 42 SRL fuel element dejacketing waste solution. The in-cell tests reproduced the preliminary bench-scale test results. The initial Cs breakthrough range was 85--92 column volumes (CV). The resin capacity for Cs was found to be {approximately}0.35 meq per gram of resin. A 1.5-liter resin bed loaded a combined {approximately}1,300 Ci of {sup 134}Cs and {sup 137}Cs. A distribution coefficient of {approximately}110 CV was determined, based on a 50% Cs breakthrough point. The kinetics of the system was studied by examining the rate parameters; however, it was decided that several more tests would be necessary to define the mass transfer characteristics of the system.

  13. Impact of temperature on the arbuscular mycorrhizal (AM) symbiosis: growth responses of the host plant and its AM fungal partner.

    PubMed

    Heinemeyer, A; Fitter, A H

    2004-02-01

    The growth response of the hyphae of mycorrhizal fungi has been determined, both when plant and fungus together and when only the fungus was exposed to a temperature change. Two host plant species, Plantago lanceolata and Holcus lanatus, were grown separately in pots inoculated with the mycorrhizal fungus Glomus mosseae at 20/18 degrees C (day/night); half of the pots were then transferred to 12/10 degrees C. Plant and fungal growth were determined at six sequential destructive harvests. A second experiment investigated the direct effect of temperature on the length of the extra-radical mycelium (ERM) of three mycorrhizal fungal species. Growth boxes were divided in two equal compartments by a 20 micro m mesh, allowing only the ERM and not roots to grow into a fungal compartment, which was either heated (+8 degrees C) or kept at ambient temperature. ERM length (LERM) was determined on five sampling dates. Growth of H. lanatus was little affected by temperature, whereas growth of P. lanceolata increased with temperature, and both specific leaf area (SLA) and specific root length (SRL) increased independently of plant size. Percentage of colonized root (LRC) and LERM were positively correlated with temperature when in symbiosis with P. lanceolata, but differences in LRC were a function of plant biomass. Colonization was very low in H. lanatus roots and there was no significant temperature effect. In the fungal compartment LERM increased over time and was greatest for Glomus mosseae. Heating the fungal compartment significantly increased LERM in two of the three species but did not affect LRC. However, it significantly increased SRL of roots in the plant compartment, suggesting that the fungus plays a regulatory role in the growth dynamics of the symbiosis. These temperature responses have implications for modelling carbon dynamics under global climate change.

  14. Functional divergence between the two P1-P2 stalk dimers on the ribosome in their interaction with ricin A chain.

    PubMed

    Grela, Przemysław; Li, Xiao-Ping; Tchórzewski, Marek; Tumer, Nilgun E

    2014-05-15

    The eukaryotic stalk, which is responsible for the recruitment of translation factors, is a pentamer containing two P1-P2 dimers with unclear modes of action. In Saccharomyces cerevisiae, P1/P2 proteins (individual P1 and P2 proteins) are organized into two distinct dimers, P1A-P2B and P1B-P2A. To investigate the functional contribution of each dimer on the ribosome, RTA (ricin A chain), which binds to the stalk to depurinate the SRL (sarcin/ricin loop), was used as a molecular probe in yeast mutants in which the binding site for one or the other dimer on P0 was deleted. Ribosome depurination and toxicity of RTA were greatly reduced in mutants containing only P1A-P2B on the ribosome, whereas those with only P1B-P2A were reduced less in depurination and were unaffected in toxicity. Ribosomes bearing P1B-P2A were depurinated by RTA at a similar level as wild-type, but ribosomes bearing P1A-P2B were depurinated at a much lower level in vitro. The latter ribosomes showed the lowest association and almost no dissociation with RTA by surface plasmon resonance. These results indicate that the P1B-P2A dimer is more critical for facilitating the access of RTA to the SRL, providing the first in vivo evidence for functional divergence between the two stalk dimers on the ribosome.

  15. Intraspecific variation in root and leaf traits and leaf-root trait linkages in eight aspen demes (Populus tremula and P. tremuloides)

    PubMed Central

    Hajek, Peter; Hertel, Dietrich; Leuschner, Christoph

    2013-01-01

    Leaf and fine root morphology and physiology have been found to vary considerably among tree species, but not much is known about intraspecific variation in root traits and their relatedness to leaf traits. Various aspen progenies (Populus tremula and P. tremuloides) with different growth performance are used in short-rotation forestry. Hence, a better understanding of the link between root trait syndromes and the adaptation of a deme to a particular environment is essential in order to improve the match between planted varieties and their growth conditions. We examined the between-deme (genetic) and within-deme (mostly environmental) variation in important fine root traits [mean root diameter, specific root area (SRA) and specific root length (SRL), root tissue density (RTD), root tip abundance, root N concentration] and their co-variation with leaf traits [specific leaf area (SLA), leaf size, leaf N concentration] in eight genetically distinct P. tremula and P. tremuloides demes. Five of the six root traits varied significantly between the demes with largest genotypic variation in root tip abundance and lowest in mean root diameter and RTD (no significant difference). Within-deme variation in root morphology was as large as between-deme variation suggesting a relatively low genetic control. Significant relationships existed neither between SLA and SRA nor between leaf N and root N concentration in a plant. Contrary to expectation, high aboveground relative growth rates (RGR) were associated with large, and not small, fine root diameters with low SRA and SRL. Compared to leaf traits, the influence of root traits on RGR was generally low. We conclude that aspen exhibits large intraspecific variation in leaf and also in root morphological traits which is only partly explained by genetic distances. A root order-related analysis might give deeper insights into intraspecific root trait variation. PMID:24155751

  16. The A1 Subunit of Shiga Toxin 2 Has Higher Affinity for Ribosomes and Higher Catalytic Activity than the A1 Subunit of Shiga Toxin 1.

    PubMed

    Basu, Debaleena; Li, Xiao-Ping; Kahn, Jennifer N; May, Kerrie L; Kahn, Peter C; Tumer, Nilgun E

    2015-10-19

    Shiga toxin (Stx)-producing Escherichia coli (STEC) infections can lead to life-threatening complications, including hemorrhagic colitis (HC) and hemolytic-uremic syndrome (HUS), which is the most common cause of acute renal failure in children in the United States. Stx1 and Stx2 are AB5 toxins consisting of an enzymatically active A subunit associated with a pentamer of receptor binding B subunits. Epidemiological evidence suggests that Stx2-producing E. coli strains are more frequently associated with HUS than Stx1-producing strains. Several studies suggest that the B subunit plays a role in mediating toxicity. However, the role of the A subunits in the increased potency of Stx2 has not been fully investigated. Here, using purified A1 subunits, we show that Stx2A1 has a higher affinity for yeast and mammalian ribosomes than Stx1A1. Biacore analysis indicated that Stx2A1 has faster association and dissociation with ribosomes than Stx1A1. Analysis of ribosome depurination kinetics demonstrated that Stx2A1 depurinates yeast and mammalian ribosomes and an RNA stem-loop mimic of the sarcin/ricin loop (SRL) at a higher catalytic rate and is a more efficient enzyme than Stx1A1. Stx2A1 depurinated ribosomes at a higher level in vivo and was more cytotoxic than Stx1A1 in Saccharomyces cerevisiae. Stx2A1 depurinated ribosomes and inhibited translation at a significantly higher level than Stx1A1 in human cells. These results provide the first direct evidence that the higher affinity for ribosomes in combination with higher catalytic activity toward the SRL allows Stx2A1 to depurinate ribosomes, inhibit translation, and exhibit cytotoxicity at a significantly higher level than Stx1A1.

  17. Patterns of structural and defense investments in fine roots of Scots pine (Pinus sylvestris L.) across a strong temperature and latitudinal gradient in Europe.

    PubMed

    Zadworny, Marcin; McCormack, M Luke; Żytkowiak, Roma; Karolewski, Piotr; Mucha, Joanna; Oleksyn, Jacek

    2017-03-01

    Plant functional traits may be altered as plants adapt to various environmental constraints. Cold, low fertility growing conditions are often associated with root adjustments to increase acquisition of limiting nutrient resources, but they may also result in construction of roots with reduced uptake potential but higher tissue persistence. It is ultimately unclear whether plants produce fine roots of different structure in response to decreasing temperatures and whether these changes represent a trade-off between root function or potential root persistence. We assessed patterns of root construction based on various root morphological, biochemical and defense traits including root diameter, specific root length (SRL), root tissue density (RTD), C:N ratio, phenolic compounds, and number of phellem layers across up to 10 root orders in diverse populations of Scots pine along a 2000-km climatic gradient in Europe. Our results showed that different root traits are related to mean annual temperature (MAT) and expressed a pattern of higher root diameter and lower SRL and RTD in northern sites with lower MAT. Among absorptive roots, we observed a gradual decline in chemical defenses (phenolic compounds) with decreasing MAT. In contrast, decreasing MAT resulted in an increase of structural protection (number of phellem layers) in transport fine roots. This indicated that absorptive roots with high capacity for nutrient uptake, and transport roots with low uptake capacity, were characterized by distinct and contrasting trade-offs. Our observations suggest that diminishing structural and chemical investments into the more distal, absorptive roots in colder climates is consistent with building roots of higher absorptive capacity. At the same time, roots that play a more prominent role in transport of nutrients and water within the root system saw an increase in structural investment, which can increase persistence and reduce long-term costs associated with their frequent

  18. ANL technical support program for DOE Office of Environmental Management. Annual report, October 1994--September 1995

    SciTech Connect

    Bates, J.K.; Buck, E.C.; Dietz, N.L.; DiSanto, T.; Ebert, W.L.

    1996-07-01

    A program was established for the DOE Office of Environmental Management (EM) to evaluate factors that are anticipated to affect waste glass reaction during repository disposal, especially in an unsaturated environment typical of what may be expected for the proposed Yucca Mountain repository site. This report covers progress in FY 1995 on the following tasks: (1) Tests are ongoing to evaluate and compare the reactivity of fully radioactive glasses with that of glasses having the same compositions except for the absence of radionuclides under conditions representative of a high-level waste repository environment. Data from these tests will be used to evaluate the effect of radionuclides on the glass corrosion behavior and to determine the disposition of the radionuclides as the glass corrodes. Static dissolution tests and unsaturated tests are being conducted with several Defense Waste Processing Facility (DWPF) and West Valley Demonstration Project (WVDP) glasses. (2) A series of static dissolution tests is being performed to compare the corrosion behavior of nuclear waste glasses made with SRL 131 and SRL 202 frits at different S/V ratios. The S/V ratio affects the extent to which dissolved glass species are diluted; the solution chemistry then affects continued glass dissolution. The solutions generated in tests at high S/V ratios are conducive to the formation of alteration phases that may be deleterious to the glass. After long time periods, the glass dissolution rates of both glasses increase coincidentally with the formation of analcime and other alteration phases. However, the release of radionuclides from the glasses into solution is controlled by their individual solubilities.

  19. Human Body Temperature (37°C) Increases the Expression of Iron, Carbohydrate, and Amino Acid Utilization Genes in Escherichia coli K-12▿

    PubMed Central

    White-Ziegler, Christine A.; Malhowski, Amy J.; Young, Sarah

    2007-01-01

    Using DNA microarrays, we identified 126 genes in Escherichia coli K-12 whose expression is increased at human body temperature (37°C) compared to growth at 23°C. Genes involved in the uptake and utilization of amino acids, carbohydrates, and iron dominated the list, supporting a model in which temperature serves as a host cue to increase expression of bacterial genes needed for growth. Using quantitative real-time PCR, we investigated the thermoregulatory response for representative genes in each of these three categories (hisJ, cysP, srlE, garP, fes, and cirA), along with the fimbrial gene papB. Increased expression at 37°C compared to 23°C was retained in both exponential and stationary phases for all of the genes and in most of the various media tested, supporting the relative importance of this cue in adapting to changing environments. Because iron acquisition is important for both growth and virulence, we analyzed the regulation of the iron utilization genes cirA and fes and found that growth in iron-depleted medium abrogated the thermoregulatory effect, with high-level expression at both temperatures, contrasting with papB thermoregulation, which was not greatly altered by limiting iron levels. A positive role for the environmental regulator H-NS was found for fes, cirA, hisJ, and srlE transcription, whereas it had a primarily negative effect on cysP and garP expression. Together, these studies indicate that temperature is a broadly used cue for regulating gene expression in E. coli and that H-NS regulates iron, carbohydrate, and amino acid utilization gene expression. PMID:17526711

  20. Zone of capture analysis for the A/M area of the Savannah River Site

    SciTech Connect

    Haselow, J.; Beaudoin, C.M.; Schreuder, P.J.

    1991-12-01

    The groundwater of the A/M Area of the Savannah River Site (SRS) is contaminated with trichloroethylene (TCE) and perchloroethylene (PCE) as the result of the past use and disposal of these solvents. For the purpose of remediating this contamination, the A/M Area of the SRS has been divided into three sectors termed the central, northern (or SRL), and southern sectors. The central portion of the A/M Area has had an active remediation system of eleven recovery wells since 1985 and its effectiveness has been evaluated through groundwater modeling. Remediation will soon begin at the northern or SRL sector with a pump and treat system of six wells distributed at four different locations with total pumping of approximately 250 gallons per minute (gpm). The locations and effectiveness of the capture system for each sector has been estimated through groundwater modeling without full consideration of the central recovery system. This report will provide an estimate of the number of recovery wells required for the southern sector and also consider the effects of the current and planned recovery systems for the northern and central plumes. The southern sector contamination (which is defined as the area south of the M-Area basin) has been initially characterized and one recovery well (RWM-16) has been installed, for which an aquifer test was performed. However, to date a recovery well system has not been designed for the southern sector nor has a comprehensive evaluation of the recovery systems for all three sectors been completed. The purpose of this groundwater modeling study is to: (1) determine the location and number of recovery wells necessary to contain or remediate the southern sector, and (2) complete an analysis of the combined central, northern and estimated southern sector remediation so that the interactions of the systems can be determined.

  1. Evaluation of volatile organic compound (VOC) blank data and application of study reporting levels to groundwater data collected for the California GAMA Priority Basin Project, May 2004 through September 2010

    USGS Publications Warehouse

    Fram, Miranda S.; Olsen, Lisa D.; Belitz, Kenneth

    2012-01-01

    Volatile organic compounds (VOCs) were analyzed in quality-control samples collected for the California Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project. From May 2004 through September 2010, a total of 2,026 groundwater samples, 211 field blanks, and 109 source-solution blanks were collected and analyzed for concentrations of 85 VOCs. Results from analyses of these field and source-solution blanks and of 2,411 laboratory instrument blanks during the same time period were used to assess the quality of data for the 2,026 groundwater samples. Eighteen VOCs were detected in field blanks or source-solution blanks: acetone, benzene, bromodichloromethane, 2-butanone, carbon disulfide, chloroform, 1,1-dichloroethene, dichloromethane, ethylbenzene, tetrachloroethene, styrene, tetrahydrofuran, toluene, trichloroethene, trichlorofluoromethane, 1,2,4-trimethylbenzene, m- and p-xylenes, and o-xylene. The objective of the evaluation of the VOC-blank data was to determine if study reporting levels (SRLs) were needed for any of the VOCs detected in blanks to ensure the quality of the data from groundwater samples. An SRL is equivalent to a raised reporting level that is used in place of the reporting level used by the analyzing laboratory [long‑term method detection level (LT-MDL) or laboratory reporting level (LRL)] to reduce the probability of reporting false-positive detections. Evaluation of VOC-blank data was done in three stages: (1) identification of a set of representative quality‑control field blanks (QCFBs) to be used for calculation of SRLs and identification of VOCs amenable to the SRL approach, (2) evaluation of potential sources of contamination to blanks and groundwater samples by VOCs detected in field blanks, and (3) selection of appropriate SRLs from among four potential SRLs for VOCs detected in field blanks and application of those SRLs to the groundwater data. An important conclusion from this study is that to ensure the

  2. Successful application of spatial difference technique to electron energy-loss spectroscopy studies of Mo/SrTiO3 interfaces.

    PubMed

    Gao, M; Scheu, C; Tchernychova, E; Rühle, M

    2003-04-01

    The electron energy-loss near-edge structure (ELNES) of Mo/SrTiO3 interfaces has been studied using high spatial resolution electron energy-loss spectroscopy (EELS) in a dedicated scanning transmission electron microscope. Thin films of Mo with a thickness of 50 nm were grown on (001)-orientated SrTiO3 surfaces by molecular beam epitaxy at 600 degrees C. High-resolution transmission electron microscopy revealed that the interfaces were atomically abrupt with the (110)Mo plane parallel to the substrate surface. Ti-L2,3 ( approximately 460 eV), O-K ( approximately 530 eV), Sr-L2,3 ( approximately 1950 eV) and Mo-L2,3 ( approximately 2500 eV) absorption edges were acquired by using the Gatan Enfina parallel EELS system with a CCD detector. The interface-specific components of the ELNES were extracted by employing the spatial difference method. The interfacial Ti-L2,3 edge shifted to lower energy values and the splitting due to crystal field became less pronounced compared to bulk SrTiO3, which indicated that the Ti atoms at the interface were in a reduced oxidation state and that the symmetry of the TiO6 octahedra was disturbed. No interfacial Sr-L2,3 edge was observed, which may demonstrate that Sr atoms do not participate in the interfacial bonding. An evident interface-specific O-K edge was found, which differs from that of the bulk in both position (0.8 +/- 0.2 eV positive shift) and shape. In addition, a positive shift (0.9 +/- 0.3 eV) occurred for the interfacial Mo-L2,3, revealing an oxidized state of Mo at the interface. Our results indicated that at the interface SrTiO3 was terminated with TiO2. The validity of the spatial difference technique is discussed and examined by introducing subchannel drift intentionally.

  3. X-SAR as high-performance interferometric SAR

    NASA Astrophysics Data System (ADS)

    Werner, Marian U.; Schandl, Josef

    1995-11-01

    In April and October 1994 the X-SAR radar has been flown twice onboard the Space Shuttle, as part of the Space Radar Laboratory (SRL-1 and SRL-2). This radar payload is the first synthetic aperture radar (SAR) system of its kind in space, with three frequencies, multi- polarization, variable incidence angle and variable modes of operation. SIR-C/X-SAR, the new generation of imaging microwave remote sensing sensors from space, demonstrated successfully repeat pass interferometry in all three frequencies with a one day repeat as well as a six month repeat orbit. The major problems with the repeat orbit interferometry are the temporal target decorrelation, unsuitable baseline and different squint angles for the two passes to be processed. Therefore, for the third mission of the Space Radar Lab which shall be called SRTM (shuttle radar topographic mapper), single pass interferometry with a second receive antenna is proposed to generate a topographic map of all land surfaces between +60 degrees and -56 degrees latitude. X-SAR's 12 meter long and 40 cm wide main transmit and receive antenna is mounted directly to a tiltable part of the SIR-C antenna truss structure in the Shuttle cargo bay. The second receive antenna is 6 meters long and is mounted together with the second C-band antenna to a 31 meter long deployable boom structure perpendicular to the velocity direction to build the baseline. X-SAR is not capable of operating in a scan SAR model like SIR-C to allow continuous coverage, but will operate in a high resolution mode with a swath width of 30 - 35 km. The engineering design of the interferometric configuration for X-SAR, the requirement specifications, and the predicted performance as well as the mission operation aspects are described in this paper. SIR-C/X- SAR is a cooperative project. The SIR-C instrument was developed by NASA's Jet Propulsion Laboratory (JPL). The X-band radar (X-SAR) was developed by the Dornier and Alenia Spazio Companies for the German

  4. Managing Risk for Cassini During Mission Operations and Data Analysis (MOandDA)

    NASA Technical Reports Server (NTRS)

    Witkowski, Mona M.

    2002-01-01

    A Risk Management Process has been tailored for Cassini that not only satisfies the requirements of NASA and JPL, but also allows the Program to proactively identify and assess risks that threaten mission objectives. Cassini Risk Management is a team effort that involves both management and engineering staff. The process is managed and facilitated by the Mission Assurance Manager (MAM), but requires regular interactions with Program Staff and team members to instill the risk management philosophy into the day to day mission operations. While Risk Management is well defined for projects in the development phase, it is a relatively new concept for Mission Operations. The Cassini team has embraced this process and has begun using it in an effective, proactive manner, to ensure mission success. It is hoped that the Cassini Risk Management Process will form the basis by which risk management is conducted during MO&DA on future projects. proactive in identifying, assessing and mitigating risks before they become problems. Cost ehtiveness is achieved by: Comprehensively identifying risks Rapidly assessing which risks require the expenditure of pruject cewums Taking early actions to mitigate these risks Iterating the process frequently, to be responsive to the dynamic internal and external environments The Cassini Program has successfully implemented a Risk Management Process for mission operations, The initial SRL has been developed and input into he online tool. The Risk Management webbased system has been rolled out for use by the flight team and risk owners we working proactive in identifying, assessing and mitigating risks before they become problems. Cost ehtiveness is achieved by: Comprehensively identifying risks Rapidly assessing which risks require the expenditure of pruject cewums Taking early actions to mitigate these risks Iterating the process frequently, to be responsive to the dynamic internal and external environments The Cassini Program has successfully

  5. Using CFD as a Rocket Injector Design Tool: Recent Progress at Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Tucker, Kevin; West, Jeff; Williams, Robert; Lin, Jeff; Canabal, Francisco; Rocker, marvin; Robles, Bryan; Garcia, Robert; Chenoweth, James

    2005-01-01

    New programs are forcing American propulsion system designers into unfamiliar territory. For instance, industry s answer to the cost and reliability goals set out by the Next Generation Launch Technology Program are engine concepts based on the Oxygen- Rich Staged Combustion Cycle. Historical injector design tools are not well suited for this new task. The empirical correlations do not apply directly to the injector concepts associated with the ORSC cycle. These legacy tools focus primarily on performance with environment evaluation a secondary objective. Additionally, the environmental capability of these tools is usually one-dimensional while the actual environments are at least two- and often three-dimensional. CFD has the potential to calculate performance and multi-dimensional environments but its use in the injector design process has been retarded by long solution turnaround times and insufficient demonstrated accuracy. This paper has documented the parallel paths of program support and technology development currently employed at Marshall Space Flight Center in an effort to move CFD to the forefront of injector design. MSFC has established a long-term goal for use of CFD for combustion devices design. The work on injector design is the heart of that vision and the Combustion Devices CFD Simulation Capability Roadmap that focuses the vision. The SRL concept, combining solution fidelity, robustness and accuracy, has been established as a quantitative gauge of current and desired capability. Three examples of current injector analysis for program support have been presented and discussed. These examples are used to establish the current capability at MSFC for these problems. Shortcomings identified from this experience are being used as inputs to the Roadmap process. The SRL evaluation identified lack of demonstrated solution accuracy as a major issue. Accordingly, the MSFC view of code validation and current MSFC-funded validation efforts were discussed in

  6. Standardized method to quantify the variation in voxel value distribution in patient-simulated CBCT data sets

    PubMed Central

    Gotfredsen, E; Wenzel, A

    2015-01-01

    Objectives: To suggest a standardized method to assess the variation in voxel value distribution in patient-simulated CBCT data sets and the effect of time between exposures (TBE). Additionally, a measurement of reproducibility, Aarhus measurement of reproducibility (AMORe), is introduced, which could be used for quality assurance purposes. Methods: Six CBCT units were tested [Cranex® 3D/CRAN (Soredex Oy, Tuusula, Finland); Scanora® 3D/SCAN (Soredex Oy); NewTom™ 5G/NEW5 (QR srl, Verona, Italy); i-CAT/ICAT (Imaging Sciences International, Hatfield, PA); 3D Accuitomo FPD80/ACCU (Morita, Kyoto, Japan); and NewTom VG/NEWV (QR srl)]. Two sets of volumetric data of a wax-imbedded dry human skull (containing a titanium implant) were acquired by each CBCT unit at two sessions on separate days. Each session consisted 21 exposures: 1 “initial” followed by a 30-min interval (initial data set), 10 acquired with 30-min TBE (data sets 1–10) and 10 acquired with 15-min TBE (data sets 11–20). CBCT data were exported as digital imaging and communications in medicine files and converted to text files containing x, y and z positions and grey shade for each voxel. Subtractions were performed voxel-by-voxel in two set-ups: (1) between two consecutive data sets and (2) between any subsequent data set and data set 1. The mean grey shade variation for each voxel was calculated for each unit/session. Results: The largest mean grey shade variation was found in the subtraction set-up 2 (27–447 shades of grey, depending on the unit). Considering subtraction set-up 1, the highest variation was seen for NEW5, between data sets 1 and the initial. Conclusions: Discrepancies in voxel value distribution were found by comparing the initial examination of the day with the subsequent examinations. TBE had no predictable effect on the variation of CBCT-derived voxel values. AMORe ranged between 0 and 64. PMID:25354021

  7. Sample Canister Capture Mechanism for Mars Sample Return: Functional and environmental test of the elegant breadboard model

    NASA Astrophysics Data System (ADS)

    Carta, R.; Filippetto, D.; Lavagna, M.; Mailland, F.; Falkner, P.; Larranaga, J.

    2015-12-01

    The paper provides recent updates about the ESA study: Sample Canister Capture Mechanism Design and Breadboard developed under the Mars Robotic Exploration Preparation (MREP) program. The study is part of a set of feasibility studies aimed at identifying, analysing and developing technology concepts enabling the future international Mars Sample Return (MSR) mission. The MSR is a challenging mission with the purpose of sending a Lander to Mars, acquire samples from its surface/subsurface and bring them back to Earth for further, more in depth, analyses. In particular, the technology object of the Study is relevant to the Capture Mechanism that, mounted on the Orbiter, is in charge of capturing and securing the Sample Canister, or Orbiting Sample, accommodating the Martian soil samples, previously delivered in Martian orbit by the Mars Ascent Vehicle. An elegant breadboard of such a device was implemented and qualified under an ESA contract primed by OHB-CGS S.p.A. and supported by Politecnico di Milano, Department of Aerospace Science and Technology: in particular, functional tests were conducted at PoliMi-DAST and thermal and mechanical test campaigns occurred at Serms s.r.l. facility. The effectiveness of the breadboard design was demonstrated and the obtained results, together with the design challenges, issues and adopted solutions are critically presented in the paper. The breadboard was also tested on a parabolic flight to raise its Technology Readiness Level to 6; the microgravity experiment design, adopted solutions and results are presented as well in the paper.

  8. Raman lidar and sun photometer measurements of aerosols and water vapor during the ARM RCS experiment

    NASA Technical Reports Server (NTRS)

    Ferrare, R. A.; Whiteman, D. N.; Melfi, S. H.; Evans, K. D.; Holben, B. N.

    1995-01-01

    The first Atmospheric Radiation Measurement (ARM) Remote Cloud Study (RCS) Intensive Operations Period (IOP) was held during April 1994 at the Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site near Lamont, Oklahoma. This experiment was conducted to evaluate and calibrate state-of-the-art, ground based remote sensing instruments and to use the data acquired by these instruments to validate retrieval algorithms developed under the ARM program. These activities are part of an overall plan to assess general circulation model (GCM) parameterization research. Since radiation processes are one of the key areas included in this parameterization research, measurements of water vapor and aerosols are required because of the important roles these atmospheric constituents play in radiative transfer. Two instruments were deployed during this IOP to measure water vapor and aerosols and study their relationship. The NASA/Goddard Space Flight Center (GSFC) Scanning Raman Lidar (SRL) acquired water vapor and aerosol profile data during 15 nights of operations. The lidar acquired vertical profiles as well as nearly horizontal profiles directed near an instrumented 60 meter tower. Aerosol optical thickness, phase function, size distribution, and integrated water vapor were derived from measurements with a multiband automatic sun and sky scanning radiometer deployed at this site.

  9. Dryline on 22 May 2002 During IHOP: Convective Scale Measurements at the Profiling Site

    NASA Technical Reports Server (NTRS)

    Demoz, Belay; Flamant, Cyrille; Miller, David; Evans, Keith; Fabry, Federic; DiGirolamo, Paolo; Whiteman, David; Geerts, Bart; Weckwerth, Tammy; Brown, William

    2004-01-01

    A unique set of measurements of wind, water vapor mixing ratio and boundary layer height variability was observed during the first MOP dryline mission of 22 May 2002. Water vapor mixing ratio from the Scanning Raman Lidar (SRL), high-resolution profiles of aerosol backscatter from the HARLIE and wind profiles from the GLOW are combined with the vertical velocity derived from the NCAR/ISS/MAPR and the high-resolution FMCW radar to reveal the convective variability of the cumulus cloud-topped boundary layer. A combined analysis of the in-situ and remote sensing data from aircraft, radiosonde, lidars, and radars reveals moisture variability within boundary layer updraft and downdraft regions as well as characterizes the boundary layer height variability in the dry and moist sides of the dryline. The profiler site measurements will be tied to aircraft data to reveal the relative intensity and location of these updrafts to the dry line. This study provides unprecedented high temporal and spatial resolution measurements of wind, moisture and backscatter within a dryline and the associated convective boundary layer.

  10. Geology of the Delta, Escalante, Price, Richfield, and Salina 1/sup 0/ x 2/sup 0/ quadrangles, Utah

    SciTech Connect

    Thayer, P.A.

    1981-11-01

    The National Uranium Resource Evaluation (NURE) program was established to evaluate domestic uranium resources in the continental United States and to identify areas favorable for uranium exploration. The Grand Junction Office of the Department of Energy is responsible for administering the program. The Savannah River Laboratory (SRL) is responsible for hydrogeochemical and stream-sediment reconnaissance (HSSR) of 3.9 million km/sup 2/ (1,500,000 mi/sup 2/) in 37 eastern and western states. This document provides geologic and mineral resources reports for the Delta, Escalante, Price, Richfield, and Salina 1/sup 0/ x 2/sup 0/ National Topographic Map Series quadrangles, Utah. The purpose of these reports is to provide background geologic and mineral resources information to aid in the interpretation of NURE geochemical reconnaissance data. Except for the Escalante Quadrangle, each report is accompanied by a geologic map and a mineral locality map (Plates 1-8, in pocket). The US Geological Survey previously published a 1/sup 0/ x 2/sup 0/ geologic map of the Escalante Quadrangle and described the uranium deposits in the area (Hackman and Wyant, 1973). NURE hydrogeochemical and stream-sediment reconnaissance data for these quadrangles have been issued previously in some of the reports included in the references.

  11. Ricin uses arginine 235 as an anchor residue to bind to P-proteins of the ribosomal stalk

    PubMed Central

    Zhou, Yijun; Li, Xiao-Ping; Chen, Brian Y.; Tumer, Nilgun E.

    2017-01-01

    Ricin toxin A chain (RTA) binds to stalk P-proteins to reach the α–sarcin/ricin loop (SRL) where it cleaves a conserved adenine. Arginine residues at the RTA/RTB interface are involved in this interaction. To investigate the individual contribution of each arginine, we generated single, double and triple arginine mutations in RTA. The R235A mutation reduced toxicity and depurination activity more than any other single arginine mutation in yeast. Further reduction in toxicity, depurination activity and ribosome binding was observed when R235A was combined with a mutation in a nearby arginine. RTA interacts with the ribosome via a two-step process, which involves slow and fast interactions. Single arginine mutations eliminated the fast interactions with the ribosome, indicating that they increase the binding rate of RTA. Arginine residues form a positively charged patch to bind to negatively charged residues at the C-termini of P-proteins. When electrostatic interactions conferred by the arginines are lost, hydrophobic interactions are also abolished, suggesting that the hydrophobic interactions alone are insufficient to allow binding. We propose that Arg235 serves as an anchor residue and cooperates with nearby arginines and the hydrophobic interactions to provide the binding specificity and strength in ribosome targeting of RTA. PMID:28230053

  12. Chemical and structural stability of lithium-ion battery electrode materials under electron beam.

    PubMed

    Lin, Feng; Markus, Isaac M; Doeff, Marca M; Xin, Huolin L

    2014-07-16

    The investigation of chemical and structural dynamics in battery materials is essential to elucidation of structure-property relationships for rational design of advanced battery materials. Spatially resolved techniques, such as scanning/transmission electron microscopy (S/TEM), are widely applied to address this challenge. However, battery materials are susceptible to electron beam damage, complicating the data interpretation. In this study, we demonstrate that, under electron beam irradiation, the surface and bulk of battery materials undergo chemical and structural evolution equivalent to that observed during charge-discharge cycling. In a lithiated NiO nanosheet, a Li2CO3-containing surface reaction layer (SRL) was gradually decomposed during electron energy loss spectroscopy (EELS) acquisition. For cycled LiNi(0.4)Mn(0.4)Co(0.18)Ti(0.02)O2 particles, repeated electron beam irradiation induced a phase transition from an layered structure to an rock-salt structure, which is attributed to the stoichiometric lithium and oxygen removal from 3a and 6c sites, respectively. Nevertheless, it is still feasible to preserve pristine chemical environments by minimizing electron beam damage, for example, using fast electron imaging and spectroscopy. Finally, the present study provides examples of electron beam damage on lithium-ion battery materials and suggests that special attention is necessary to prevent misinterpretation of experimental results.

  13. Towards a research pole in photonics in Western Romania

    NASA Astrophysics Data System (ADS)

    Duma, Virgil-Florin; Negrutiu, Meda L.; Sinescu, Cosmin; Rominu, Mihai; Miutescu, Eftimie; Burlea, Amelia; Vlascici, Miomir; Gheorghiu, Nicolae; Cira, Octavian; Hutiu, Gheorghe; Mnerie, Corina; Demian, Dorin; Marcauteanu, Corina; Topala, Florin; Rolland, Jannick P.; Voiculescu, Ioana; Podoleanu, Adrian G.

    2014-07-01

    We present our efforts in establishing a Research Pole in Photonics in the future Arad-Timisoara metropolitan area projected to unite two major cities of Western Romania. Research objectives and related training activities of various institutions and groups that are involved are presented in their evolution during the last decade. The multi-disciplinary consortium consists principally of two universities, UAVA (Aurel Vlaicu University of Arad) and UMF (Victor Babes Medicine and Pharmacy University of Timisoara), but also of the Arad County Emergency University Hospital and several innovative SMEs, such as Bioclinica S.A. (the largest array of medical analysis labs in the region) and Inteliform S.R.L. (a competitive SME focused on mechatronics and mechanical engineering). A brief survey of the individual and joint projects of these institutions is presented, together with their teaching activities at graduate and undergraduate level. The research Pole collaborates in R&D, training and education in biomedical imaging with universities in USA and Europe. Collaborative activities, mainly on Optical Coherence Tomography (OCT) projects are presented in a multidisciplinary approach that includes optomechatronics, precision mechanics and optics, dentistry, medicine, and biology.

  14. Vegetation survey of Pen Branch and Four Mile Creek wetlands

    SciTech Connect

    Not Available

    1992-10-01

    One hundred-fifty plots were recently sampled (vegetational sampling study) at the Savannah River Site (SRS). An extensive characterization of the vascular flora, in four predetermined strata (overstory, Understory, shrub layer, and ground cover), was undertaken to determine dominance, co-dominance, and the importance value (I.V.) of each species. These results will be used by the Savannah River Laboratory (SRL) to evaluate the environmental status of Four Mile Creek, Pen Branch, and two upland pine stands. Objectives of this study were to: Describe in detail the plant communities previously mapped with reference to the topography and drainage, including species of plants present: Examine the successional trends within each sampling area and describe the extent to which current vegetation communities have resulted from specific earlier vegetation disturbances (e.g., logging and grazing); describe in detail the botanical field techniques used to sample the flora; describe the habitat and location of protected and/or rare species of plants; and collect and prepare plant species as herbarium quality specimens. Sampling was conducted at Four Mile Creek and Pen Branch, and in two upland pine plantations of different age growth.

  15. Vegetation survey of Pen Branch and Four Mile Creek wetlands

    SciTech Connect

    Not Available

    1992-01-01

    One hundred-fifty plots were recently sampled (vegetational sampling study) at the Savannah River Site (SRS). An extensive characterization of the vascular flora, in four predetermined strata (overstory, Understory, shrub layer, and ground cover), was undertaken to determine dominance, co-dominance, and the importance value (I.V.) of each species. These results will be used by the Savannah River Laboratory (SRL) to evaluate the environmental status of Four Mile Creek, Pen Branch, and two upland pine stands. Objectives of this study were to: Describe in detail the plant communities previously mapped with reference to the topography and drainage, including species of plants present: Examine the successional trends within each sampling area and describe the extent to which current vegetation communities have resulted from specific earlier vegetation disturbances (e.g., logging and grazing); describe in detail the botanical field techniques used to sample the flora; describe the habitat and location of protected and/or rare species of plants; and collect and prepare plant species as herbarium quality specimens. Sampling was conducted at Four Mile Creek and Pen Branch, and in two upland pine plantations of different age growth.

  16. Data acquisition with Masscomp

    SciTech Connect

    Collins, A.J.

    1988-12-31

    Applications and products for data acquisition and control are abundant. Systems and boards for Apple or IBM products collect, store, and manipulate data up to rates in the 10`s of thousands. These systems may suit your application; if so, it would be good for you to obtain one of these systems. However, if you need speed in the hundreds of thousands of samples per second and you want to store, process, and display data in real time, data acquisition becomes much more complex. Operating system code has to be sufficient to handle the load. A company known as Massachusetts Computer Corporation has modified UNIX operating system code to allow real time data acquisition and control. They call this operating system Real Time Unix, or RTU. They have built a family of computer systems around this operating system with specialized hardware to handle multiple processes and quick communications, which a real time operating system needs to function. This paper covers the basics of an application using a Masscomp 5520 computer. The application is for the KYLE Project Cold Tests in SRL. KYLE is a classified weapons program. The data flow from source to Masscomp, the generic features of Masscomp systems, and the specifics of the Masscomp computer related to this application will be presented.

  17. The EarthServer Federation: State, Role, and Contribution to GEOSS

    NASA Astrophysics Data System (ADS)

    Merticariu, Vlad; Baumann, Peter

    2016-04-01

    The intercontinental EarthServer initiative has established a European datacube platform with proven scalability: known databases exceed 100 TB, and single queries have been split across more than 1,000 cloud nodes. Its service interface being rigorously based on the OGC "Big Geo Data" standards, Web Coverage Service (WCS) and Web Coverage Processing Service (WCPS), a series of clients can dock into the services, ranging from open-source OpenLayers and QGIS over open-source NASA WorldWind to proprietary ESRI ArcGIS. Datacube fusion in a "mix and match" style is supported by the platform technolgy, the rasdaman Array Database System, which transparently federates queries so that users simply approach any node of the federation to access any data item, internally optimized for minimal data transfer. Notably, rasdaman is part of GEOSS GCI. NASA is contributing its Web WorldWind virtual globe for user-friendly data extraction, navigation, and analysis. Integrated datacube / metadata queries are contributed by CITE. Current federation members include ESA (managed by MEEO sr.l.), Plymouth Marine Laboratory (PML), the European Centre for Medium-Range Weather Forecast (ECMWF), Australia's National Computational Infrastructure, and Jacobs University (adding in Planetary Science). Further data centers have expressed interest in joining. We present the EarthServer approach, discuss its underlying technology, and illustrate the contribution this datacube platform can make to GEOSS.

  18. Robotics development programs overview

    SciTech Connect

    Heckendorn, F.M.

    1990-11-01

    This paper discusses the applications of robotics at the Westinghouse Savannah River Site. The Savannah River Laboratory (SRL) continues to provide support to the Savannah River Site (SRS) in many areas of Robotics and Remote Vision. An overview of the current and near term future developments are presented. The driving forces for Robotics and Vision developments at SRS include the classic reasons for industrial robotics installation (i.e. repetitive and undesirable jobs) and those reasons related to radioactive environments. Protection of personnel from both radiation and radioactive contamination benefit greatly from both Robotics and Telerobotics. Additionally, the quality of information available from remote locations benefits greatly from the ability to visually monitor and remotely sense. The systems discussed include a glovebox waste handling and bagout robot, a shielded cells robot for radioactive waste sample transfer, waste handling gantry robots, a two armed master/slave manipulator as an attachment to a gantry robot, navigation robot research/testing, demonstration of the mobile underwater remote cleaning and inspection device, a camera deployment robot to support remote crane operations and for deployment of radiation sensors directly over a hazardous site, and demonstration of a large mobile robot for high radiation environments. Development of specialized and limited life vision/viewing systems for hazardous environments is also discussed.

  19. Off-gas characteristics of defense waste vitrification using liquid-fed Joule-heated ceramic melters

    SciTech Connect

    Goles, R.W.; Sevigny, G.J.

    1983-09-01

    Off-gas and effluent characterization studies have been established as part of a PNL Liquid-Fed Ceramic Melter development program supporting the Savannah River Laboratory Defense Waste Processing Facility (SRL-DWPF). The objectives of these studies were to characterize the gaseous and airborne emission properties of liquid-fed joule-heated melters as a function of melter operational parameters and feed composition. All areas of off-gas interest and concern including effluent characterization, emission control, flow rate behavior and corrosion effects have been studied using alkaline and formic-acid based feed compositions. In addition, the behavioral patterns of gaseous emissions, the characteristics of melter-generated aerosols and the nature and magnitude of melter effluent losses have been established under a variety of feeding conditions with and without the use of auxiliary plenum heaters. The results of these studies have shown that particulate emissions are responsible for most radiologically important melter effluent losses. Melter-generated gases have been found to be potentially flammable as well as corrosive. Hydrogen and carbon monoxide present the greatest flammability hazard of the combustibles produced. Melter emissions of acidic volatile compounds of sulfur and the halogens have been responsible for extensive corrosion observed in melter plenums and in associated off-gas lines and processing equipment. The use of auxiliary plenum heating has had little effect upon melter off-gas characteristics other than reducing the concentrations of combustibles.

  20. Examining parents' ratings of middle-school students' academic self-regulation using principal axis factoring analysis.

    PubMed

    Chen, Peggy P; Cleary, Timothy J; Lui, Angela M

    2015-09-01

    This study examined the reliability and validity of a parent rating scale, the Self-Regulation Strategy Inventory: Parent Rating Scale (SRSI-PRS), using a sample of 451 parents of sixth- and seventh-grade middle-school students. Principal axis factoring (PAF) analysis revealed a 3-factor structure for the 23-item SRSI-PRS: (a) Managing Behavior and Learning (α = .92), (b) Maladaptive Regulatory Behaviors (α = .76), and (c) Managing Environment (α = .84). The majority of the observed relations between these 3 subscales, and the SRSI-SR, student motivation beliefs, and student mathematics grades were statistically significant and in the small to medium range. After controlling for various student variables and motivation indices of parental involvement, 2 SRSI-PRS factors (Managing Behavior and Learning, Maladaptive Regulatory Behaviors) reliably predicted students' achievement in their mathematics course. This study provides initial support for the validity and reliability of the SRSI-PRS and underscores the advantages of obtaining parental ratings of students' SRL behaviors.

  1. Workshop on the leaching mechanisms of nuclear-waste forms, October 27-28, 1981. Summary report

    SciTech Connect

    Mendel, J.E.

    1982-04-01

    The purpose of this informal workshop was to initiate the program and achieve the following goals: (1) acquaint laboratory investigators (data generators) with the needs of the mathematical modelers (data users). Session I was devoted to a tutorial by D.D. Jackson, mathematical modeler for the leaching mechanisms program, on PROTOCOL, a general case waste form leaching model; (2) define important testing parameters, based on the present state of knowledge. To achieve this, a number of important testing parameters were identified for special discussion in Session II; (3) develop an understanding of the interrelationships between the activities of leaching mechanisms program participants, and begin definition of the specific role of each participant in the overall program; and (4) establish good communication between the leaching mechanisms program and related programs, particularly the waste form leaching program at the Savannah River Laboratory (SRL) and the various Nuclear Waste Terminal Storage (NWTS) waste package programs. The agenda for the workshop is attached as Appendix A; a list of attendees is in Appendix B. Because this workshop was devoted to preliminary planning for the leaching mechanisms program, the presentations and discussions were purposely kept informal. This report represents a synopsis of the proceedings that has been prepared by the leaching mechanisms coordinator and reviewed by the workshop participants.

  2. Structure of the nocturnal boundary layer over a complex terrain

    SciTech Connect

    Parker, M.J. ); Raman, S. . Dept. of Marine, Earth and Atmospheric Sciences)

    1992-01-01

    The complex nature of the nocturnal boundary layer (NBL) has been shown extensively in the literature Project STABLE was conducted in 1988 to study NBL turbulence and diffusion over the complex terrain of the Savannah River Site (SRS) near Augusta, Georgia. The third night of the study was particularly interesting because of the unusual phenomena observed in the structure of the NBL. Further analyses of microscale and mesoscale data from this night are presented using data from SRS network of eight 61 m towers over 900 km{sup 2}, from six launches of an instrumented tethersonde, from permanent SRL meteorological instrumentation at seven levels of the 304 m (1,000 ft) WJBF-TV tower near SRS, and additional data collected at 36 m (CC) by North Carolina State University (NCSU) including a one dimensional sonic anemometer, fine wire thermocouple, and a three dimensional propeller anemometer. Also, data from the nearby Plant Vogtle nuclear power plant observation tower and the National Weather Service at Augusta's Bush Field (AGS) are presented. The passage of a mesoscale phenomenon, defined as a microfront (with an explanation of the nomenclature used), and a vertical composite schematic of the NBL which shows dual low level wind maxima, dual inversions, and a persistent, elevated turbulent layer over a complex terrain are described.

  3. Structure of the nocturnal boundary layer over a complex terrain

    SciTech Connect

    Parker, M.J.; Raman, S.

    1992-08-01

    The complex nature of the nocturnal boundary layer (NBL) has been shown extensively in the literature Project STABLE was conducted in 1988 to study NBL turbulence and diffusion over the complex terrain of the Savannah River Site (SRS) near Augusta, Georgia. The third night of the study was particularly interesting because of the unusual phenomena observed in the structure of the NBL. Further analyses of microscale and mesoscale data from this night are presented using data from SRS network of eight 61 m towers over 900 km{sup 2}, from six launches of an instrumented tethersonde, from permanent SRL meteorological instrumentation at seven levels of the 304 m (1,000 ft) WJBF-TV tower near SRS, and additional data collected at 36 m (CC) by North Carolina State University (NCSU) including a one dimensional sonic anemometer, fine wire thermocouple, and a three dimensional propeller anemometer. Also, data from the nearby Plant Vogtle nuclear power plant observation tower and the National Weather Service at Augusta`s Bush Field (AGS) are presented. The passage of a mesoscale phenomenon, defined as a microfront (with an explanation of the nomenclature used), and a vertical composite schematic of the NBL which shows dual low level wind maxima, dual inversions, and a persistent, elevated turbulent layer over a complex terrain are described.

  4. Preface to the focus section on injection-induced seismicity

    USGS Publications Warehouse

    Eaton, David; Rubinstein, Justin L.

    2015-01-01

    The ongoing, dramatic increase in seismicity in the central United States that began in 2009 is believed to be the result of injection‐induced seismicity (Ellsworth, 2013). Although the basic mechanism for activation of slip on a fault by subsurface fluid injection is well established (Healy et al., 1968; Raleighet al., 1976; Nicholson and Wesson, 1992; McGarr et al., 2002; Ellsworth, 2013), the occurrence of damaging M≥5 earthquakes and the dramatic increase in seismicity in the central United States has brought heightened attention to this issue. The elevated seismicity is confined to a limited number of areas, and accumulating evidence indicates that the seismicity in these locations is directly linked to nearby industrial operations. This Seismological Research Letters (SRL) focus section presents a selected set of seven technical papers that cover various aspects of this topic, including basic seismological and ground‐motion observations, case studies, numerical simulation of fault activation, and risk mitigation.

  5. Some results of processing NURE geochemical sampling in the northern Rocky Mountain area

    SciTech Connect

    Thayer, P.A.; Cook, J.R.; Price, V. Jr.

    1980-01-01

    The National Uranium Resource Evaluation (NURE) program was begun in the spring of 1973 to evaluate domestic uranium resources in the continental United States and to identify areas favorable for uranium exploration. The significance of the distribution of uranium in natural waters and sediments will be assessed as an indicator of favorable areas for the discovery of uranium deposits. This paper is oriented primarily to the discussion of stream sediments. Data for the Challis 1/sup 0/ x 2/sup 0/ NTMS quadrangle will be used for specific samples of NURE data processing. A high-capacity neutron activation analysis facility at SRL is used to determine uranium and about 19 other elements in hydrogeochemical samples. Evaluation of the areal distributions of uranium ratios demonstrate that most of the high U/Hf, U/Th and U/(Th + Hf) ratios occur scattered throughout the western two-thirds of the quadrangle. Most of the higher ratio values are found in samples taken at sites underlain by granitic rocks of the Idaho batholith or Tertiary-age plutons.

  6. Astrocomp: web technologies for high performance computing on a network of supercomputers

    NASA Astrophysics Data System (ADS)

    Costa, A.; Becciani, U.; Miocchi, P.; Antonuccio, V.; Capuzzo Dolcetta, R.; Di Matteo, P.; Rosato, V.

    2005-02-01

    Astrocomp is a project developed by the INAF-Astrophysical Observatory of Catania, University of Roma La Sapienza and Enea in collaboration with Oneiros s.r.l. The project has the goal of building a web-based user-friendly interface which allows the international community to run some parallel codes on a set of high-performance computing (HPC) resources, with no need for specific knowledge about Unix and Operating Systems commands. Astrocomp provides CPU times, on parallel systems, available to the authorized user. The portal makes codes for astronomy available: FLY code, a cosmological code for studying three-dimensional collisionless self-gravitating systems with periodic boundary conditions [Becciani, Antonuccio, Comput. Phys. Comm. 136 (2001) 54]. ATD treecode, a parallel tree-code for the simulation of the dynamics of self-gravitating systems [Miocchi, Capuzzo Dolcetta, A&A 382 (2002) 758]. MARA a code for stellar light curves analysis [Rodonò et al., A&A 371 (2001) 174]. Other codes will be added to the portal in the future.

  7. Contextual role of TRLs and MRLs in technology management.

    SciTech Connect

    Fernandez, Joseph A.

    2010-11-01

    Technology Readiness Levels (TRLs) have been used extensively from the 1970s, especially in the National Aeronautics and Space Administration (NASA). Their application was recommended by the General Accounting Office in 1999 to be used for major Department of Defense acquisition projects. Manufacturing Readiness Levels (MRLs) have been proposed for improving the way manufacturing risks and readiness are identified; they were introduced to the defense community in 2005, but have not been used as broadly as TRLs. Originally TRLs were used to assess the readiness of a single technology. With the emergence of more complex systems and system of systems, it has been increasingly recognized that TRLs have limitations, especially when considering integration of complex systems. Therefore, it is important to use TRLs in the correct context. Details on TRLs and MRLs are reported in this paper. More recent indices to establish a better understanding of the integrated readiness state of systems are presented. Newer readiness indices, System Readiness Levels (SRLs) and Integration Readiness Levels, are discussed and their limitations and advantages are presented, along with an example of computing SRLs. It is proposed that a modified SRL be considered that explicitly includes the MRLs and a modification of the TRLs to include the Integrated Technology Index (ITI) and/or the Advancement Degree of Difficulty index proposed by NASA. Finally, the use of indices to perform technology assessments are placed into the overall context of technology management, recognizing that factors to transition and manage technology include cost, schedule, manufacturability, integration readiness, and technology maturity.

  8. Pilot test of a vacuum extraction system for environmental remediation of chlorinated solvents at the Savannah River Site

    SciTech Connect

    Looney, B.B.; Pickett, J.B. ); Malot, J.J. )

    1991-12-29

    Vacuum extraction is an environmental restoration technique that is currently being applied to the remediation of soils and shallow segments that are contaminated with volatile constituents. In 1987, a h study was performed to evaluate the performance and potential applicability of this technology at the Savannah River Site (SRS). Vacuum extraction is useful when volatile constituents are present in the vadose zone. The technology has been used to remediate a number of sites across the country, including leading underground storage tanks, spill sites, landfill, and production facilities. The primary objective of the pilot study was to test the performance of the technology under the conditions specific to many of the potential areas of application at SRS. There is only a limited body of literature documenting field studiesin similar environments with in sands and clayey zones and a relatively thick vadose zone. Careful studies of this type are needed to develop full scale designs at SRS. The vacuum extraction pilot study at SRS was performed by a mm consisting of technical representatives of the Environmental Sciences Section in the Savannah River Laboratory (SRL), the Raw Materials Engineering and Technology Section of SRS, and TerraVac Inc., a subcontractor with experience in this field.

  9. Calcium Homeostasis and Muscle Energy Metabolism Are Modified in HspB1-Null Mice

    PubMed Central

    Picard, Brigitte; Kammoun, Malek; Gagaoua, Mohammed; Barboiron, Christiane; Meunier, Bruno; Chambon, Christophe; Cassar-Malek, Isabelle

    2016-01-01

    Hsp27—encoded by HspB1—is a member of the small heat shock proteins (sHsp, 12–43 kDa (kilodalton)) family. This protein is constitutively present in a wide variety of tissues and in many cell lines. The abundance of Hsp27 is highest in skeletal muscle, indicating a crucial role for muscle physiology. The protein identified as a beef tenderness biomarker was found at a crucial hub in a functional network involved in beef tenderness. The aim of this study was to analyze the proteins impacted by the targeted invalidation of HspB1 in the Tibialis anterior muscle of the mouse. Comparative proteomics using two-dimensional gel electrophoresis revealed 22 spots that were differentially abundant between HspB1-null mice and their controls that could be identified by mass spectrometry. Eighteen spots were more abundant in the muscle of the mutant mice, and four were less abundant. The proteins impacted by the absence of Hsp27 belonged mainly to calcium homeostasis (Srl and Calsq1), contraction (TnnT3), energy metabolism (Tpi1, Mdh1, PdhB, Ckm, Pygm, ApoA1) and the Hsp proteins family (HspA9). These data suggest a crucial role for these proteins in meat tenderization. The information gained by this study could also be helpful to predict the side effects of Hsp27 depletion in muscle development and pathologies linked to small Hsps. PMID:28248227

  10. Network connectivity enhancement by exploiting all optical multicast in semiconductor ring laser

    NASA Astrophysics Data System (ADS)

    Siraj, M.; Memon, M. I.; Shoaib, M.; Alshebeili, S.

    2015-03-01

    The use of smart phone and tablet applications will provide the troops for executing, controlling and analyzing sophisticated operations with the commanders providing crucial documents directly to troops wherever and whenever needed. Wireless mesh networks (WMNs) is a cutting edge networking technology which is capable of supporting Joint Tactical radio System (JTRS).WMNs are capable of providing the much needed bandwidth for applications like hand held radios and communication for airborne and ground vehicles. Routing management tasks can be efficiently handled through WMNs through a central command control center. As the spectrum space is congested, cognitive radios are a much welcome technology that will provide much needed bandwidth. They can self-configure themselves, can adapt themselves to the user requirement, provide dynamic spectrum access for minimizing interference and also deliver optimal power output. Sometimes in the indoor environment, there are poor signal issues and reduced coverage. In this paper, a solution utilizing (CR WMNs) over optical network is presented by creating nanocells (PCs) inside the indoor environment. The phenomenon of four-wave mixing (FWM) is exploited to generate all-optical multicast using semiconductor ring laser (SRL). As a result same signal is transmitted at different wavelengths. Every PC is assigned a unique wavelength. By using CR technology in conjunction with PC will not only solve network coverage issue but will provide a good bandwidth to the secondary users.

  11. High energy electron beam processing experiments with induction accelerators

    NASA Astrophysics Data System (ADS)

    Goodman, D. L.; Birx, D. L.; Dave, V. R.

    1995-05-01

    Induction accelerators are capable of producing very high electron beam power for processing at energies of 1-10 MeV. A high energy electron beam (HEEB) material processing system based on all-solid-state induction accelerator technology is in operation at Science Research Laboratory. The system delivers 50 ns 500 A current pulses at 1.5 MeV and is capable of operating at high power (500 kW) and high (˜ 5 kHz) repetition rate. HEEB processing with induction accelerators is useful for a wide variety of applications including the joining of high temperature materials, powder metallurgical fabrication, treatment of organic-contaminated wastewater and the curing of polymer matrix composites. High temperature HEEB experiments at SRL have demonstrated the brazing of carbon-carbon composites to metallic substrates and the melting and sintering of powders for graded-alloy fabrication. Other experiments have demonstrated efficient destruction of low-concentration organic contaminants in water and low temperature free-radical cross-linking of fiber-reinforced composites with acrylated resin matrices.

  12. Carbon Nanotube Micro-Needles for Rapid Transdermal Drug Delivery

    NASA Astrophysics Data System (ADS)

    Lyon, Bradley; Aria, Adrianus Indrat; Gat, Amir; Cosse, Julia; Montemayor, Lauren; Beizaie, Masoud; Gharib, Morteza

    2012-11-01

    By catalyst patterning, bundles of vertically-aligned carbon nanotubes (CNT) can be assembled to create 2D arrays of hollow micro-needles with feature size as small as a few microns. For transdermal drug delivery, the most challenging mechanical requirement is to make the CNT micro-needle small enough so that delivery is painless yet large enough so that the micro-needle can achieve skin penetration. By taking advantage of capillary action and the nanoporosity of CNT bundles, we can wick high strength polymer into the inter-spacing between nanotubes to augment the stiffness of our micro-needles. For low viscous polymers, the large ratio between the micron sized center hole of the micro-needle and the nanopores of the surrounding CNT allow us to wick polymer through the nanotubes while maintaining an open central hole for drug transport. For a transdermal patch prototype with a delivery area less than 1cm x 1cm square, we can fabricate 50 CNT micro-needles that produces a total flow rate up to 100 uL/s with actuation pressure provided by a mere finger tap. From in vitro experiments, we will demonstrate that CNT micro-needles provide a much faster convective delivery of drugs than conventional topical diffusion based patches. We acknowledge Zcube s.r.l for their support of this work.

  13. Development and Validation of an HPLC Method for the Analysis of Sirolimus in Drug Products

    PubMed Central

    Islambulchilar, Ziba; Ghanbarzadeh, Saeed; Emami, Shahram; Valizadeh, Hadi; Zakeri-Milani, Parvin

    2012-01-01

    Purpose: The aim of this study was to develop a simple, rapid and sensitive reverse phase high performance liquid chromatography (RP-HPLC) method for quantification of sirolimus (SRL) in pharmaceutical dosage forms. Methods: The chromatographic system employs isocratic elution using a Knauer- C18, 5 mm, 4.6 × 150 mm. Mobile phase consisting of acetonitril and ammonium acetate buffer set at flow rate 1.5 ml/min. The analyte was detected and quantified at 278nm using ultraviolet detector. The method was validated as per ICH guidelines. Results: The standard curve was found to have a linear relationship (r2 > 0.99) over the analytical range of 125–2000ng/ml. For all quality control (QC) standards in intraday and interday assay, accuracy and precision range were -0.96 to 6.30 and 0.86 to 13.74 respectively, demonstrating the precision and accuracy over the analytical range. Samples were stable during preparation and analysis procedure. Conclusion: Therefore the rapid and sensitive developed method can be used for the routine analysis of sirolimus such as dissolution and stability assays of pre- and post-marketed dosage forms. PMID:24312784

  14. Lidar Applications in Atmospheric Dynamics: Measurements of Wind, Moisture and Boundary Layer Evolution

    NASA Technical Reports Server (NTRS)

    Demoz, Belay; Whiteman, David; Gentry, Bruce; Schwemmer, Geary; Evans, Keith; DiGirolamo, Paolo; Comer, Joseph

    2005-01-01

    A large array of state-of-the-art ground-based and airborne remote and in-situ sensors were deployed during the International H2O Project (THOP), a field experiment that took place over the Southern Great Plains (SGP) of the United States from 13 May to 30 June 2002. These instruments provided extensive measurements of water vapor mixing ratio in order to better understand the influence of its variability on convection and on the skill of quantitative precipitation prediction (Weckwerth et all, 2004). Among the instrument deployed were ground based lidars from NASA/GSFC that included the Scanning Raman Lidar (SRL), the Goddard Laboratory for Observing Winds (GLOW), and the Holographic Airborne Rotating Lidar Instrument Experiment (HARLIE). A brief description of the three lidars is given below. This study presents ground-based measurements of wind, boundary layer structure and water vapor mixing ratio measurements observed by three co-located lidars during MOP at the MOP ground profiling site in the Oklahoma Panhandle (hereafter referred as Homestead). This presentation will focus on the evolution and variability of moisture and wind in the boundary layer when frontal and/or convergence boundaries (e.g. bores, dry lines, thunderstorm outflows etc) were observed.

  15. A distributed UNIX-based simulator

    SciTech Connect

    Wyatt, P.W.; Arnold, T.R.; Hammer, K.E. ); Peery, J.S.; McKaskle, G.A. . Dept. of Nuclear Engineering)

    1990-01-01

    One of the problems confronting the designers of simulators over the last ten years -- particularly the designers of nuclear plant simulators -- has been how to accommodate the demands of their customers for increasing verisimilitude, especially in the modeling of as-faulted conditions. The demand for the modeling of multiphase multi-component thermal-hydraulics, for example, imposed a requirement that taxed the ingenuity of the simulator software developers. Difficulty was encountered in fitting such models into the existing simulator framework -- not least because the real-time requirement of training simulation imposed severe limits on the minimum time step. In the mid-1980's, two evolutions that had been proceeding for some time culminated in mature products of potentially great utility to simulation. One was the emergence of low-cost work stations featuring not only versatile, object-oriented graphics, but also considerable number-crunching capabilities of their own. The other was the adoption of UNIX as a standard'' operating system common to at least some machines offered by virtually all vendors. As a result, it is possible to design a simulator whose graphics and executive functions are off-loaded to one or more work stations, which are designed to handle such tasks. The number-crunching duties are assigned to another machine, which has been designed expressly for that purpose. This paper deals with such a distributed UNIX-based simulator developed at the Savannah River Laboratory using graphics supplied by Texas A M University under contract to SRL.

  16. Gravimetry, rotation and angular momentum of Jupiter from the Juno Radio Science experiment

    NASA Astrophysics Data System (ADS)

    Serra, D.; Dimare, L.; Tommei, G.; Milani, A.

    2016-12-01

    Juno is a NASA space mission to Jupiter, arriving at the planet in July 2016. Through accurate Doppler tracking in X and Ka-band, the Radio Science experiment will allow to map Jupiter's gravity field, crucial for the study of the interior structure of the planet. In this paper we describe the results of numerical simulations of this experiment, performed with the ORBIT14 orbit determination software, developed by the Department of Mathematics of the University of Pisa and by the spin-off Space Dynamics Services srl. Our analysis included the determination of Jupiter's gravity field, the Love numbers, the direction of the rotation axis and the angular momentum magnitude, the latter by measuring the Lense-Thirring effect on the spacecraft. As far as the gravity field is concerned, the spherical harmonics coefficients of Jupiter's gravitational potential are highly correlated and the accuracy in the determination of the zonal coefficients of degree ℓ is degraded for ℓ > 15 . We explore the possibility of using a local model, introducing ring-shaped mascons, so as to determine the gravity field of the portion of the spherical surface bounded by latitudes 6°N and 35°N, the latitude belt observed during Juno's pericenter passes. Finally, the determination of Jupiter's angular momentum magnitude turned out to be compromised by the impossibility of separating the effects of the Lense-Thirring acceleration and of a change in Jupiter's rotation axis direction.

  17. Neutron activation and other analytical data for plutonic rocks from North America and Africa. National Uranium Resource Evaluation

    SciTech Connect

    Price, V.; Fay, W.M.; Cook, J.R.

    1982-09-01

    The objective of this report is to retrieve the elements of an analytical study of granites and associated other plutonic rocks which was begun as a part of the U.S. Department of Energy's National Uranium Resource Evaluation (NURE) program. A discussion of the Savannah River Laboratory (SRL) neutron activation analysis system is given so that a user will understand the linmitations of the data. Enough information is given so that an experienced geochemist can clean up the data set to the extent required by any project. The data are generally good as they are presented. It is intended that the data be read from a magnetic tape written to accompany this report. Microfiche tables of the data follow the text. These tables were prepared from data on the tape, and programs which will read the tape are presented in the section THE DATA TAPE. It is our intent to write a later paper which will include a thoroughly scrubbed data set and a technical discussion of results of the study. 1 figure.

  18. Plutonium scrap recovery at Savannah River: Past, present, and vision of the future

    SciTech Connect

    Gray, L.W.; Gray, J.H.; Blancett, A.L.; Lower, M.W.; Rudisill, T.S.

    1988-01-01

    As a result of the changing requirement, plus environmental and regulatory commitments, SRP now has essentially completed its paradigm shift. SRP has been transformed from primarily a reprocessor of irradiated uranium targets to primarily a reprocessor of non-specification plutonium. This is the mission which will carry SRP into the 21st Century. Accomplishment of the defined goals for the three-pronged RandD program will achieve several objectives: exploit new processes for recovering low-grade scraps; enhance SRP's position to incorporate pyrochemical processes where they are attractive or beneficial to plant scrap recovery; provide SRL/SRP with a capability to develop compatible aqueous pyrochemical processes; identify material compatibility requirements for the incorporation of pyrochemical processes at SRP; promote development and demonstration of improved NDA instrumentation to accurately measure plutonium holdups in solid residues; identify and implement the technology required for reagent preparation and atmospheric quality control; provide a means to compare economic options for emerging new processes; and as a result, identify process steps which will also put SRP in a position to readily adapt to changing plutonium missions.

  19. Compact, lightweight CO/sub 2/ lasers for SDIO applications. Final report, 30 September 1988-31 March 1989

    SciTech Connect

    Jacob, J.

    1989-04-11

    During the past decade, substantial investments have been made in the development of gas-discharge-pumped CO/sub 2/ lasers for military and civilian applications. The DoD community and SDIO in particular is developing compact, lightweight CO/sub 2/ lasers for airborne and spaced-based radar applications directed toward target ranging, imaging, and discrimination. These CO/sub 2/ laser systems are being developed under the SDIO Lowkater Program, in the Airborne Laser Experiment (ALE) Program by the Army/SDC and in Lincoln Laboratory's space based CO/sub 2/ laser radar research and development program. The three major components of a CO/sub 2/ laser radar are the laser head and flow loop, the pulsed-power system and the optics and beam-control system. In this report, SRL presents a novel self-sustained discharge concept that should result in the stable and efficient extraction of large specific energies (50 J/liter atmosphere) for pulse lengths as long as 100 micro s.

  20. Comparison of Aerosol Optical Properties and Water Vapor Among Ground and Airborne Lidars and Sun Photometers During TARFOX

    NASA Technical Reports Server (NTRS)

    Ferrare, R.; Ismail, S.; Browell, E.; Brackett, V.; Clayton, M.; Kooi, S.; Melfi, S. H.; Whiteman, D.; Schwemmer, G.; Evans, K.; Russell, P.; Livingston, J.; Schmid, B.; Holben, B.; Remer, L.; Smirnov, A.; Hobbs, P. V.

    2000-01-01

    We compare aerosol optical thickness (AOT) and precipitable water vapor (PWV) measurements derived from ground and airborne lidars and Sun photometers during TARFOX (Tropospheric Aerosol Radiative Forcing Observational Experiment). Such comparisons are important to verify the consistency between various remote sensing measurements before employing them in any assessment of the impact of aerosols on the global radiation balance. Total scattering ratio and extinction profiles measured by the ground-based NASA/GSFC Scanning Raman Lidar (SRL) system, which operated from Wallops Island, Virginia (37.86 deg N, 75.51 deg W), are compared with those measured by the Lidar Atmospheric Sensing Experiment (LASE) airborne lidar system aboard the NASA ER-2 aircraft. Bias and rms differences indicate that these measurements generally agreed within about 10%. Aerosol extinction profiles and estimates of AOT are derived from both lidar measurements using a value for the aerosol extinction/backscattering ratio S(sub a)=60 sr for the aerosol extinction/backscattering ratio, which was determined from the Raman lidar measurements.

  1. The Regulation of Task Performance: A Trans-Disciplinary Review

    PubMed Central

    Clark, Ian; Dumas, Guillaume

    2016-01-01

    Definitions of meta-cognition typically have two components: (1) knowledge about one's own cognitive functioning; and, (2) control over one's own cognitive activities. Since Flavell and his colleagues provided the empirical foundation on which to build studies of meta-cognition and the autonoetic (self) knowledge required for effective learning, the intervening years have seen the extensive dissemination of theoretical and empirical research on meta-cognition, which now encompasses a variety of issues and domains including educational psychology and neuroscience. Nevertheless, the psychological and neural underpinnings of meta-cognitive predictions and reflections that determine subsequent regulation of task performance remain ill understood. This article provides an outline of meta-cognition in the science of education with evidence drawn from neuroimaging, psycho-physiological, and psychological literature. We will rigorously explore research that addresses the pivotal role of the prefrontal cortex (PFC) in controlling the meta-cognitive processes that underpin the self-regulated learning (SRL) strategies learners employ to regulate task performance. The article delineates what those strategies are, and how the learning environment can facilitate or frustrate strategy use by influencing learners' self-efficacy. PMID:26779050

  2. A climatological description of the Savannah River Site

    SciTech Connect

    Hunter, C.H.

    1990-05-22

    This report provides a general climatological description of the Savannah River Site. The description provides both regional and local scale climatology. The regional climatology includes a general regional climatic description and presents information on occurrence frequencies of the severe meteorological phenomena that are important considerations in the design and siting of a facility. These phenomena include tornadoes, thunderstorms, hurricanes, and ice/snow storms. Occurrence probabilities given for extreme tornado and non-tornado winds are based on previous site specific studies. Local climatological conditions that are significant with respect to the impact of facility operations on the environment are described using on-site or near-site meteorological data. Summaries of wind speed, wind direction, and atmospheric stability are primarily based on the most recently generated five-year set of data collected from the onsite meteorological tower network (1982--86). Temperature, humidity, and precipitation summaries include data from SRL's standard meteorological instrument shelter and the Augusta National Weather Service office at Bush Field through 1986. A brief description of the onsite meteorological monitoring program is also provided. 24 refs., 15 figs., 22 tabs.

  3. STS-68 Space Shuttle mission report

    NASA Technical Reports Server (NTRS)

    Fricke, Robert W., Jr.

    1995-01-01

    The STS-68 Space Shuttle Program Mission Report summarizes the Payload activities as well as the Orbiter, External Tank (ET), Solid Rocket Booster (SRB), Redesigned Solid Rocket Motor (RSRM), and the Space Shuttle main engine (SSME) systems performance during the sixty-fifth flight of the Space Shuttle Program and the seventh flight of the Orbiter vehicle Endeavour (OV-105). In addition to the Orbiter, the flight vehicle consisted of an ET that was designated ET-65; three SSMEs that were designated as serial numbers 2028, 2033, and 2026 in positions 1, 2, and 3, respectively; and two SRBs that were designated BI-067. The RSRMs that were installed in each SRB were designated as 360W040A for the left SRB and 360W040B for the right SRB. The primary objective of this flight was to successfully perform the operations of the Space Radar Laboratory-2 (SRL-2). The secondary objectives of the flight were to perform the operations of the Chromosome and Plant Cell Division in Space (CHROMEX), the Commercial Protein Crystal Growth (CPCG), the Biological Research in Canisters (BRIC), the Cosmic Radiation Effects and Activation Monitor (CREAM), the Military Application of Ship Tracks (MAST), and five Get-Away Special (GAS) payloads.

  4. Immunogenicity and Protective Efficacy of the DAR-901 Booster Vaccine in a Murine Model of Tuberculosis

    PubMed Central

    Lahey, Timothy; Laddy, Dominick; Hill, Krystal; Schaeffer, Jacqueline; Hogg, Alison; Keeble, James; Dagg, Belinda; Ho, Mei Mei; Arbeit, Robert D.; von Reyn, C. Fordham

    2016-01-01

    Background The development of a novel tuberculosis vaccine is a leading global health priority. SRL172, an inactivated, whole-cell mycobacterial vaccine, was safe, immunogenic and reduced the incidence of culture-confirmed tuberculosis in a phase III trial in HIV-infected and BCG immunized adults in Tanzania. Here we describe the immunogenicity and protective efficacy of DAR-901, a booster vaccine against tuberculosis manufactured from the same seed strain using a new scalable method. Methods We evaluated IFN-γ responses by ELISpot and antibody responses by enzyme linked immunosorbent assay in C57BL/6 and BALB/c mice after three doses of DAR-901. In an aerosol challenge model, we evaluated the protective efficacy of the DAR-901 booster in C57BL/6 mice primed with BCG and boosted with two doses of DAR-901 at 4 dosage levels in comparison with homologous BCG boost. Results DAR-901 vaccination elicited IFN-γ responses to mycobacterial antigen preparations derived from both DAR-901 and Mycobacterium tuberculosis. DAR-901 immunization enhanced antibody responses to DAR-901 but not Mycobacterium tuberculosis lysate or purified protein derivative. Among animals primed with BCG, boosting with DAR-901 at 1 mg provided greater protection against aerosol challenge than a homologous BCG boost (lungs P = 0.036, spleen P = 0.028). Conclusions DAR-901 induces cellular and humoral immunity and boosts protection from M. tuberculosis compared to a homologous BCG boost. PMID:27997597

  5. Integrated Current Limiter

    NASA Astrophysics Data System (ADS)

    Pappalardo, S.; Alfonso, M. M.; Mirabella, I. B.

    2011-10-01

    The LCL has been extensively used in ESA scientific satellites and since a few years ago is being also the baseline device for earth observation satellites such as CRYOSAT 1 and 2, SENTINAL 1, 2 and 3, EARTWATCH, etc. It seems that the use of this LCL is also being considered as an alternative to fuse approach for commercial telecommunication satellites. Scope of this document is to provide a technical description of the Integrated Current Limiter device (shortly ICL later on) developed inside the domain of ESTECContract22049-09-NL-A Twith STMicroelectronics s.r.l. (ref. Invitation to Tender AO/1-5784/08/NL/A T). The design of the ICL device takes into account both ESA and power electronics designer's experience. This experience is more than 25 years long in Europe. The ICL design has been leaded in order to be fully compliant with the applicable specification issued by ESA and the major European power electronics manufacturers that have participated in its edition.

  6. Subtropical Cirrus Properties Derived from GSFC Scanning Raman Lidar Measurements during CAMEX 3

    NASA Technical Reports Server (NTRS)

    Whiteman, D. N.; Wang, Z.; Demoz, B.

    2004-01-01

    The NASA/GSFC Scanning Raman Lidar (SRL) was stationed on Andros Island, Bahamas for the third Convection and Moisture Experiment (CAMEX 3) held in August - September, 1998 and acquired an extensive set of water vapor and cirrus cloud measurements (Whiteman et al., 2001). The cirrus data studied here have been segmented by generating mechanism. Distinct differences in the optical properties of the clouds are found when the cirrus are hurricane-induced versus thunderstom-induced. Relationships of cirrus cloud optical depth, mean cloud temperature, and layer mean extinction-to-backscatter ratio (S) are presented and compared with mid-latitude and tropical results. Hurricane-induced cirrus clouds are found to generally possess lower values of S than thunderstorm induced clouds. Comparison of these measurements of S are made with other studies revealing at times large differences in the measurements. Given that S is a required parameter for spacebased retrievals of cloud optical depth using backscatter lidar, these large diffaences in S measurements present difficulties for space-based retrievals of cirrus cloud extinction and optical depth.

  7. Reduction and coding of synthetic aperture radar data with Fourier transforms

    NASA Technical Reports Server (NTRS)

    Tilley, David G.

    1995-01-01

    Recently, aboard the Space Radar Laboratory (SRL), the two roles of Fourier Transforms for ocean image synthesis and surface wave analysis have been implemented with a dedicated radar processor to significantly reduce Synthetic Aperture Radar (SAR) ocean data before transmission to the ground. The object was to archive the SAR image spectrum, rather than the SAR image itself, to reduce data volume and capture the essential descriptors of the surface wave field. SAR signal data are usually sampled and coded in the time domain for transmission to the ground where Fourier Transforms are applied both to individual radar pulses and to long sequences of radar pulses to form two-dimensional images. High resolution images of the ocean often contain no striking features and subtle image modulations by wind generated surface waves are only apparent when large ocean regions are studied, with Fourier transforms, to reveal periodic patterns created by wind stress over the surface wave field. Major ocean currents and atmospheric instability in coastal environments are apparent as large scale modulations of SAR imagery. This paper explores the possibility of computing complex Fourier spectrum codes representing SAR images, transmitting the coded spectra to Earth for data archives and creating scenes of surface wave signatures and air-sea interactions via inverse Fourier transformations with ground station processors.

  8. idRHa+ProMod - Rail Hardening Control System

    NASA Astrophysics Data System (ADS)

    Ferro, L.

    2016-03-01

    idRHa+ProMod is the process control system developed by Primetals Technologies to foresee the thermo-mechanical evolution and micro-structural composition of rail steels subjected to slack quenching into idRHa+ Rail Hardening equipments in a simulation environment. This tool can be used both off-line or in-line, giving the user the chance to test and study the best cooling strategies or letting the automatic control system free to adjust the proper cooling recipe. Optimization criteria have been tailored in order to determine the best cooling conditions according to the metallurgical requirements imposed by the main rail standards and also taking into account the elastoplastic bending phenomena occurring during all stages of the head hardening process. The computational core of idRHa+ProMod is a thermal finite element procedure coupled with special algorithms developed to work out the main thermo-physical properties of steel, to predict the non-isothermal austenite decomposition into all the relevant phases and subsequently to evaluate the amount of latent heat of transformation released, the compound thermal expansion coefficient and the amount of plastic deformation in the material. Air mist and air blades boundary conditions have been carefully investigated by means of pilot plant tests aimed to study the jet impingement on rail surfaces and the cooling efficiency at all working conditions. Heat transfer coefficients have been further checked and adjusted directly on field during commissioning. idRHa+ is a trademark of Primetals Technologies Italy Srl

  9. Assessment of Savannah River borosilicate glass in the repository environment

    SciTech Connect

    Plodinec, M.J.; Wicks, G.G.; Bibler, N.E.

    1982-04-01

    Since 1973, borosilicate glass has been studied as a matrix for the immobilization of high-level radioactive waste generated at the Savannah River Plant (SRP). In 1977, efforts began to develop and test the large-scale equipment necessary to convert the alkaline waste slurries at SRP into a durable borosilicate glass. A process has now been developed for the proposed Defense Waste Processing Facility (DWPF) which will annually produce approximately 500 canisters of SRP waste glass which will be stored on an interim basis on the Savannah River site. Current national policy calls for the permanent disposal of high-level waste in deep geologic repositories. In the repository environment, SRP waste glass will eventually be exposed to such stresses as lithostatic or hydrostatic pressures, radiation fields, and self-heating due to radioactive decay. In addition, producing and handling each canister of glass will also expose the glass to thermal and mechanical stresses. An important objective of the extensive glass characterization and testing programs of the Savannah River Laboratory (SRL) has been to determine how these stresses affect the performance of SRP waste glass. The results of these programs indicate that: these stresses will not significantly affect the performance of borosilicate glass containing SRP waste; and SRP waste glass will effectively immobilize hazardous radionuclides in the repository environment.

  10. CARM and harmonic gyro-amplifier experiments at 17 GHz

    SciTech Connect

    Menninger, W.L.; Danly, B.G.; Alberti, S.; Chen, C.; Rullier, J.L.; Temkin, R.J.; Giguet, E. |

    1993-11-01

    Cyclotron resonance maser amplifiers are possible sources for applications such as electron cyclotron resonance heating of fusion plasmas and driving high-gradient rf linear accelerators. For accelerator drivers, amplifiers or phase locked-oscillators are required. A 17 GHz cyclotron autoresonance maser (CARM) amplifier experiment and a 17 GHz third harmonic gyro-amplifier experiment are presently underway at the MIT Plasma Fusion Center. Using the SRL/MIT SNOMAD II introduction accelerator to provide a 380 kV, 180 A, 30 ns flat top electron beam, the gyro-amplifier experiment has produced 5 MW of rf power with over 50 dB of gain at 17 GHz. The gyro-amplifier operates in the TE{sub 31} mode using a third harmonic interaction. Because of its high power output, the gyro-amplifier will be used as the rf source for a photocathode rf electron gun experiment also taking place at MIT. Preliminary gyro-amplifier results are presented, including measurement of rf power, gain versus interaction length, and the far-field pattern. A CARM experiment designed to operate in the TE{sub 11} mode is also discussed.

  11. Conversion from a calcineurin inhibitor-based immunosuppressive regimen to everolimus in renal transplant recipients: effect on renal function and proteinuria.

    PubMed

    Morales, J; Fierro, A; Benavente, D; Zehnder, C; Ferrario, M; Contreras, L; Herzog, C; Buckel, E

    2007-04-01

    New immunosuppressive agents are being actively researched to avoid complications of chronic allograft nephropathy (CAN), calcineurin inhibitor (CNI) nephrotoxicity, and posttransplantation cancer. The family of mTOR inhibitors offers a unique immunosuppressive opportunity to avoid CNI toxicity and reduce the incidence of malignancy. Nevertheless, increasing data have demonstrated that sirolimus (SRL), the first mTOR introduced in the treatment of solid organ transplant recipients, induces proteinuria, an adverse event that could produce deterioration of long-term renal function. In this short-term study of patients followed for 1 to 16 months, we examined changes in renal function and proteinuria among renal transplant recipients converted from a CNI-based regimen to an everolimus (EVL)-based one, a recently introduced mTOR inhibitor. Our data showed that renal function can be optimized after conversion to EVL by up to 42% in recipients showing CAN grade 1 or 2, or CNI nephrotoxicity. Importantly, patients who improved their creatinine clearance did not show increased proteinuria measured in a voided specimen as the ratio of urinary protein and creatinine concentration (P/C). These results, if confirmed with long-term follow-up and a larger number of patients, would allow us to consider EVL as a promising agent for maintenance immunosuppressive regimens in kidney transplantation.

  12. Flat plate heat exchangers for the new production reactor

    SciTech Connect

    Ondrejcin, R.S.

    1988-12-07

    The New Production Reactor (NPR) will require heat exchangers (HX) as part of the ancillary equipment. The most common type of heat exchanger in the US is the shell and tube, the type presently in SRP reactor service. This type of design is the one that is normally described in detail in heat transfer texts. Other designs are more efficient, and there was a period when these designs were actively modified. The largest driving force for higher efficiency HX was the OPEC produced energy shortage of the early 1970's. Several comments were made by B.S. Spangler about flat plate HX for the NPR after my initial comparison between shell and tube and flat plate HX (DPST-88-729). Since answers were not readily available, Philippe Marchal of Packinox (Louveciennes, France) agreed to visit SRL. This report contains a series of answers to all comments raised in DPST-88-743 and some general statements comparing flat plate HX to shell and tube HX. 1 fig., 2 tabs.

  13. A comparison of the performance of nuclear waste glasses by modeling

    SciTech Connect

    Grambow, B.; Strachan, D.M.

    1988-12-01

    Through a combination of data collection and computer modeling, the dissolution mechanism of nuclear waste glasses has been investigated and more clearly defined. Glass dissolution can be described as a dissolution/precipitation process in which glass dissolves in aqueous solution and solids precipitate as the solubility products are exceeded. The dissolution process is controlled by activity of the rate-limiting specie H/sub 4/SiO/sub 4/. As a concentration of H/sub 4/SiO/sub 4/ increases, the rate of dissolution decreases until a final reaction rate is reached. Between the forward reaction rate (early time) and final reaction rate (very long time), glasses may exhibit an intermediate root time dependence caused by a transport resistance for the diffusion of H/sub 4/SiO/sub 4/ within the gel layer on the glass surface. In this report, three glasses are studied: JSS-A, PNL 76-68, and SRL-131. Data from static and dynamic leach tests are assembled, plotted, and successfully modeled. The kinetic parameters for these glasses are reported. With four parameters derived from experiments for each glass, the model can be used to calculate the effects of changes in the initial composition of the water contacting the glass. The effects of convective flow can also be modeled. Furthermore, glasses of different compositions can be readily compared. 49 refs., 27 figs., 5 tabs.

  14. Early growth promotion and leaf level physiology changes in Burkholderia phytofirmans strain PsJN inoculated switchgrass.

    PubMed

    Wang, Bingxue; Mei, Chuansheng; Seiler, John R

    2015-01-01

    Switchgrass (SG) is one of the most promising next generation biofuel crops in North America. Inoculation with bacterial endophytes has improved growth of several plant species. Our study demonstrated that Burkholderia phytofirmans strain PsJN, a well-studied plant growth promoting rhizo-bacterium (PGPR) significantly increased both aboveground and belowground biomass (DW) and promoted elongation of root, stem and leaf within 17 days following inoculation. Furthermore, the enhanced root growth in PsJN inoculated plants lagged behind the shoot response, resulting in greater allocation to aboveground growth (p = 0.0041). Lower specific root length (SRL, p = 0.0158) and higher specific leaf weight (SLW, p = 0.0029) were also observed in PsJN inoculated seedlings, indicating changes in development. Photosynthetic rates (Ps) were also significantly higher in PsJN inoculated seedlings after 17 days (54%, p = 0.0016), and this occurred initially without increases in stomatal conductance resulting in significantly greater water use efficiency (WUE, 37.7%, p = 0.0467) and lower non-stomatal limitation (LNS, 29.6%, p = 0.0222). These rapid changes in leaf level physiology are at least partially responsible for the growth enhancement due to PsJN.

  15. Evaluation of Staf-Sistem 18-R for identification of staphylococcal clinical isolates to the species level.

    PubMed Central

    Piccolomini, R; Catamo, G; Picciani, C; D'Antonio, D

    1994-01-01

    The accuracy and efficiency of Staf-Sistem 18-R (Liofilchem s.r.l., Roseto degli Abruzzi, Teramo, Italy) were compared with those of conventional biochemical methods to identify 523 strains belonging to 16 different human Staphylococcus species. Overall, 491 strains (93.9%) were correctly identified (percentage of identification, > or = 90.0), with 28 (5.4%) requiring supplementary tests for complete identification. For 14 isolates (2.8%), the strains did not correspond to any key in the codebook and could not be identified by the manufacturer's computer service. Only 18 isolates (3.4%) were misidentified. The system is simple to use, is easy to handle, gives highly reproducible results, and is inexpensive. With the inclusion of more discriminating tests and adjustment in supplementary code numbers for some species, such as Staphylococcus lugdunensis and Staphylococcus schleiferi, Staf-Sistem 18-R is a suitable alternative for identification of human coagulase-positive and coagulase-negative Staphylococcus species in microbiological laboratories. Images PMID:8195373

  16. Combined Effect of Levels in Personal Self-Regulation and Regulatory Teaching on Meta-Cognitive, on Meta-Motivational, and on Academic Achievement Variables in Undergraduate Students

    PubMed Central

    de la Fuente, Jesús; Sander, Paul; Martínez-Vicente, José M.; Vera, Mariano; Garzón, Angélica; Fadda, Salvattore

    2017-01-01

    The Theory of Self- vs. Externally-Regulated Learning™ (SRL vs. ERL) proposed different types of relationships among levels of variables in Personal Self-Regulation (PSR) and Regulatory Teaching (RT) to predict the meta-cognitive, meta-motivational and -emotional variables of learning, and of Academic Achievement in Higher Education. The aim of this investigation was empirical in order to validate the model of the combined effect of low-medium-high levels in PSR and RT on the dependent variables. For the analysis of combinations, a selected sample of 544 undergraduate students from two Spanish universities was used. Data collection was obtained from validated instruments, in Spanish versions. Using an ex-post-facto design, different Univariate and Multivariate Analyses (3 × 1, 3 × 3, and 4 × 1) were conducted. Results provide evidence for a consistent effect of low-medium-high levels of PSR and of RT, thus giving significant partial confirmation of the proposed rational model. As predicted, (1) the levels of PSR and positively and significantly effected the levels of learning approaches, resilience, engagement, academic confidence, test anxiety, and procedural and attitudinal academic achievement; (2) the most favorable type of interaction was a high level of PSR with a high level RT process. The limitations and implications of these results in the design of effective teaching are analyzed, to improve university teaching-learning processes. PMID:28280473

  17. An Alternative Treatment Strategy for Complicated Chronic Wounds: Negative Pressure Therapy over Mesh Skin Graft

    PubMed Central

    Maruccia, Michele; Onesti, Maria G.; Sorvillo, Valentina; Albano, Antonio; Dessy, Luca A.; Carlesimo, Bruno; Tarallo, Mauro; Giudice, Giuseppe; Cigna, Emanuele; Ribuffo, Diego

    2017-01-01

    Extensive skin defect represents a real problem and major challenge in plastic and reconstructive surgery. On one hand, skin grafts offer a practical method to deal with skin defects despite their unsuitability for several complicated wounds. On the other hand, negative pressure wound therapy (NPWT), applied before skin grafting, promotes granulation tissue growth. The aim of the study is to evaluate the improvement in wound healing given by the merger of these two different approaches. We treated 23 patients for large wounds of multiple factors. Of these, 15 were treated with the application of V.A.C.® Therapy (KCI Medical S.r.l., Milan, Italy), in combination with skin grafts after a prior unsuccessful treatment of 4 weeks with mesh skin grafts and dressings. Another 8 were treated with only mesh skin graft. Pain reduction and wound area reduction were found statistically significant (p < 0.0009, p < 0.0001). Infection was resolved in almost all patients. According to our study, the use of the negative pressure wound therapy over mesh skin grafts is significantly effective especially in wounds resistant to conventional therapies, thereby improving the rate of skin graft take. PMID:28299333

  18. Detecting and monitoring aquacultural patterns through multitemporal SAR imagery analysis

    NASA Astrophysics Data System (ADS)

    Profeti, Giuliana; Travaglia, Carlo; Carla, Roberto

    2003-03-01

    The inventory and monitoring of aquaculture areas are essential tools for decision-making at a governmental level in developing countries. With the use of satellite imagery, these tasks can be performed in an accurate, rapid and objective way. This approach is also economically viable, as the worth of aquaculture far outweighs its cost. This paper describes a methodology for identifying and monitoring shrimp farms by means of multi-temporal satellite SAR data. SAR offer all-weather capabilities, an important characteristic since shrimp farms exist in tropical and sub-tropical areas. Moreover, the backscatter effect created by the dykes surrounding the ponds produces a typical pattern which allows the interpreter to distinguish them from other types of water-covered surfaces. However, the presence of speckle noise limits the interpretability of SAR imagery. To increase it, a multi-temporal set of four scenes covering the study area was processed by using a method that enhances time-invariant spatial features and reduces speckle without compromising the geometrical resolution of the images. The enhanced SAR imagery has proved to be valuable in identifying shrimp farm patterns with a field-tested accuracy of more than 90 percent. The methodology reported in this study has been tested with the ground truth obtained under operative conditions in Sri Lanka, thanks to the support of the FAO TCP/SRL/6712 project.

  19. Molecular characterization of the IgE-binding epitopes in the fast ω-gliadins of Triticeae in relation to wheat-dependent, exercise-induced anaphylaxis.

    PubMed

    Du, Xuye; Tang, Heng; Li, Min; Ma, Xin; Yin, Huayan; Wang, Hongwei; Zhang, Xiaocun; Qiao, Xuguang; Li, Anfei; Kong, Lingrang

    2016-10-10

    Fast ω-gliadins were minor components of wheat storage proteins but a major antigen triggering allergy to wheat. Sixty-six novel full-length fast ω-gliadin genes with unique characteristics were cloned and sequenced from wheat and its relative species using a PCR-based strategy. Their coding regions ranged from 177bp to 987bp in length and encoded 4.28kDa to 37.56kDa proteins. On the base of first three deduced amino acids at the N-terminal, these genes could be classified into the six subclasses of SRL-, TRQ-, GRL-, NRL-, SRP- and SRM-type ω-gliadin genes. Compared by multiple alignments, these genes were significantly different from each other, due to the insertion or deletion at the repetitive domain. An analysis of the IgE-binding epitopes of the 66 deduced fast ω-gliadins demonstrated that they contained 0-24 IgE-binding epitopes. The phylogenetic tree demonstrated that the fast ω-gliadins and slow ω-gliadins were separated into two groups and their divergence time was 21.64millionyears ago. Sequence data of the fast ω-gliadin genes assist in the study of the origins and evolutions of the different types of ω-gliadins while also providing a basis for the synthesis of monoclonal antibodies to detect wheat antigen content.

  20. Radar sensors for intersection collision avoidance

    NASA Astrophysics Data System (ADS)

    Jocoy, Edward H.; Phoel, Wayne G.

    1997-02-01

    On-vehicle sensors for collision avoidance and intelligent cruise control are receiving considerably attention as part of Intelligent Transportation Systems. Most of these sensors are radars and `look' in the direction of the vehicle's headway, that is, in the direction ahead of the vehicle. Calspan SRL Corporation is investigating the use of on- vehicle radar for Intersection Collision Avoidance (ICA). Four crash scenarios are considered and the goal is to design, develop and install a collision warning system in a test vehicle, and conduct both test track and in-traffic experiments. Current efforts include simulations to examine ICA geometry-dependent design parameters and the design of an on-vehicle radar and tracker for threat detection. This paper discusses some of the simulation and radar design efforts. In addition, an available headway radar was modified to scan the wide angles (+/- 90 degree(s)) associated with ICA scenarios. Preliminary proof-of-principal tests are underway as a risk reduction effort. Some initial target detection results are presented.

  1. Crystal Structure of Ribosome-Inactivating Protein Ricin A Chain in Complex with the C-Terminal Peptide of the Ribosomal Stalk Protein P2

    PubMed Central

    Shi, Wei-Wei; Tang, Yun-Sang; Sze, See-Yuen; Zhu, Zhen-Ning; Wong, Kam-Bo; Shaw, Pang-Chui

    2016-01-01

    Ricin is a type 2 ribosome-inactivating protein (RIP), containing a catalytic A chain and a lectin-like B chain. It inhibits protein synthesis by depurinating the N-glycosidic bond at α-sarcin/ricin loop (SRL) of the 28S rRNA, which thereby prevents the binding of elongation factors to the GTPase activation center of the ribosome. Here, we present the 1.6 Å crystal structure of Ricin A chain (RTA) complexed to the C-terminal peptide of the ribosomal stalk protein P2, which plays a crucial role in specific recognition of elongation factors and recruitment of eukaryote-specific RIPs to the ribosomes. Our structure reveals that the C-terminal GFGLFD motif of P2 peptide is inserted into a hydrophobic pocket of RTA, while the interaction assays demonstrate the structurally untraced SDDDM motif of P2 peptide contributes to the interaction with RTA. This interaction mode of RTA and P protein is in contrast to that with trichosanthin (TCS), Shiga-toxin (Stx) and the active form of maize RIP (MOD), implying the flexibility of the P2 peptide-RIP interaction, for the latter to gain access to ribosome. PMID:27754366

  2. Targeting ricin to the ribosome.

    PubMed

    May, Kerrie L; Yan, Qing; Tumer, Nilgun E

    2013-07-01

    The plant toxin ricin is highly toxic for mammalian cells and is of concern for bioterrorism. Ricin belongs to a family of functionally related toxins, collectively referred to as ribosome inactivating proteins (RIPs), which disable ribosomes and halt protein synthesis. Currently there are no specific antidotes against ricin or related RIPs. The catalytic subunit of ricin is an N-glycosidase that depurinates a universally conserved adenine residue within the sarcin/ricin loop (SRL) of the 28S rRNA. This depurination activity inhibits translation and its biochemistry has been intensively studied. Yet, recent developments paint a more complex picture of toxicity, with ribosomal proteins and cellular signaling pathways contributing to the potency of ricin. In particular, several studies have now established the importance of the ribosomal stalk structure in facilitating the depurination activity and ribosome specificity of ricin and other RIPs. This review highlights recent developments defining toxin-ribosome interactions and examines the significance of these interactions for toxicity and therapeutic intervention.

  3. Decentralized diagnostics based on a distributed micro-genetic algorithm for transducer networks monitoring large experimental systems

    NASA Astrophysics Data System (ADS)

    Arpaia, P.; Cimmino, P.; Girone, M.; Commara, G. La; Maisto, D.; Manna, C.; Pezzetti, M.

    2014-09-01

    Evolutionary approach to centralized multiple-faults diagnostics is extended to distributed transducer networks monitoring large experimental systems. Given a set of anomalies detected by the transducers, each instance of the multiple-fault problem is formulated as several parallel communicating sub-tasks running on different transducers, and thus solved one-by-one on spatially separated parallel processes. A micro-genetic algorithm merges evaluation time efficiency, arising from a small-size population distributed on parallel-synchronized processors, with the effectiveness of centralized evolutionary techniques due to optimal mix of exploitation and exploration. In this way, holistic view and effectiveness advantages of evolutionary global diagnostics are combined with reliability and efficiency benefits of distributed parallel architectures. The proposed approach was validated both (i) by simulation at CERN, on a case study of a cold box for enhancing the cryogeny diagnostics of the Large Hadron Collider, and (ii) by experiments, under the framework of the industrial research project MONDIEVOB (Building Remote Monitoring and Evolutionary Diagnostics), co-funded by EU and the company Del Bo srl, Napoli, Italy.

  4. Reuse metrics and measurement: A framework

    NASA Technical Reports Server (NTRS)

    Reifer, Donald J.

    1990-01-01

    The lessons learned and experience gleaned are described by those who have started to implement the reuse metrics and measurement framework used in controlling the development of common avionics and software for its affiliated aircraft programs. The framework was developed to permit the measurement of the long term cost/benefits resulting from the creation and use of Reusable Software Objects (RSOs). The framework also monitors the efficiency and effectiveness of the Software Reuse Library (SRL). The metrics and measurement framework is defined which was established to allow some determinations and findings to be made relative to software reuse. Seven criteria are discussed which were used to guide the establishment of the proposed reuse framework. Object recapture and creation metrics are explained along with their normalized use in effort, productivity, and quality determination. A single and multiple reuse instance version of a popular cost model is presented which uses these metrics and the measurement scheme proposed to predict the software effort and duration under various reuse assumptions. Studies in using this model to predict actuals taken from the RCI data base of over 1000 completed projects is discussed.

  5. Decentralized diagnostics based on a distributed micro-genetic algorithm for transducer networks monitoring large experimental systems.

    PubMed

    Arpaia, P; Cimmino, P; Girone, M; La Commara, G; Maisto, D; Manna, C; Pezzetti, M

    2014-09-01

    Evolutionary approach to centralized multiple-faults diagnostics is extended to distributed transducer networks monitoring large experimental systems. Given a set of anomalies detected by the transducers, each instance of the multiple-fault problem is formulated as several parallel communicating sub-tasks running on different transducers, and thus solved one-by-one on spatially separated parallel processes. A micro-genetic algorithm merges evaluation time efficiency, arising from a small-size population distributed on parallel-synchronized processors, with the effectiveness of centralized evolutionary techniques due to optimal mix of exploitation and exploration. In this way, holistic view and effectiveness advantages of evolutionary global diagnostics are combined with reliability and efficiency benefits of distributed parallel architectures. The proposed approach was validated both (i) by simulation at CERN, on a case study of a cold box for enhancing the cryogeny diagnostics of the Large Hadron Collider, and (ii) by experiments, under the framework of the industrial research project MONDIEVOB (Building Remote Monitoring and Evolutionary Diagnostics), co-funded by EU and the company Del Bo srl, Napoli, Italy.

  6. Anaerobiosis induces expression of ant, a new Escherichia coli locus with a role in anaerobic electron transport.

    PubMed Central

    Yerkes, J H; Casson, L P; Honkanen, A K; Walker, G C

    1984-01-01

    Escherichia coli has a formate hydrogenlyase system which allows it to maintain an electron balance during anaerobic growth by passing electrons from formate to H+ ions, thus generating H2. The Mu d1(Ap lac) bacteriophage was used to generate mutants that were defective in passing electrons from formate to benzyl viologen, an artificial electron acceptor. A subset of these mutants was studied in which beta-galactosidase was expressed at much higher levels under anaerobic conditions than under aerobic conditions. If nitrate was present during anaerobic growth, the same levels of beta-galactosidase were seen in these fusion strains as were seen under aerobic conditions. The Mu d1(Ap lac) insertions in these mutants were genetically mapped between mutS and srl and thus define a new locus we have termed ant (anaerobic electron transport). Recombinant lambda derivatives were isolated which complemented the deficiency of the ant mutants in anaerobic electron transport and also carried a trans-acting region of DNA which reduced expression of the ant-lac fusions under anaerobic conditions; a probe to the ant region was generated from one of these recombinant lambda derivatives. Southern hybridization analysis revealed that the four independent ant::Mu d1(Ap lac) fusions we isolated spanned an approximately 5-kilobase region and that all were transcribed in the same direction, counterclockwise on the E. coli genetic map. Images PMID:6425260

  7. Anaerobiosis induces expression of ant, a new Escherichia coli locus with a role in anaerobic electron transport.

    PubMed

    Yerkes, J H; Casson, L P; Honkanen, A K; Walker, G C

    1984-04-01

    Escherichia coli has a formate hydrogenlyase system which allows it to maintain an electron balance during anaerobic growth by passing electrons from formate to H+ ions, thus generating H2. The Mu d1(Ap lac) bacteriophage was used to generate mutants that were defective in passing electrons from formate to benzyl viologen, an artificial electron acceptor. A subset of these mutants was studied in which beta-galactosidase was expressed at much higher levels under anaerobic conditions than under aerobic conditions. If nitrate was present during anaerobic growth, the same levels of beta-galactosidase were seen in these fusion strains as were seen under aerobic conditions. The Mu d1(Ap lac) insertions in these mutants were genetically mapped between mutS and srl and thus define a new locus we have termed ant (anaerobic electron transport). Recombinant lambda derivatives were isolated which complemented the deficiency of the ant mutants in anaerobic electron transport and also carried a trans-acting region of DNA which reduced expression of the ant-lac fusions under anaerobic conditions; a probe to the ant region was generated from one of these recombinant lambda derivatives. Southern hybridization analysis revealed that the four independent ant::Mu d1(Ap lac) fusions we isolated spanned an approximately 5-kilobase region and that all were transcribed in the same direction, counterclockwise on the E. coli genetic map.

  8. Preliminary results and power analysis of the UAH SEDS G503 GAS can

    NASA Technical Reports Server (NTRS)

    Jalbert, Lyle B.; Mustaikis, Steven, II; Nerren, Philip

    1995-01-01

    The G-503 Get Away Special (GAS) Canister contained four experiments. A stainless steel corrosion experiment, and experiment to mix and cure concrete, a plant root growth chamber, and a group of 8 chambers to characterize diatom growth cycles in microgravity. As would be expected for this selection of experiments a significant amount of power was required to carry out these investigations over several days in a GAS environment. This was accomplished through the use of low power experiment control circuitry, heaters, and an estimate 3.6 kWh battery pack. The battery was designed around 120 standard Duracell Alkaline F cells. This pack weighed 29.5 kg (65 lbs) including a DC/DC converter and the power distribution bus for all of the experiments. Although not rechargeable, this configurations was a fraction of the cost of rechargeable systems and did not require venting to the outside of the can. Combining this with the long term storage performance, 85% of initial capacity after four years at 20 C (70 F), this guarantees sufficient power even with unexpected launch delays. This paper describes the experiments, there operation and initial results. Also, the performance of the power system during the STS-68 SRL2 mission will be addressed.

  9. Geochemical Water and Sediment Data: Reformatted Data from the National Uranium Resource Evaluation (NURE) Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) Program

    DOE Data Explorer

    Smith, Steven M. [USGS

    The National Uranium Resource Evaluation (NURE) program was initiated by the Atomic Energy Commission (AEC) in 1973 with a primary goal of identifying uranium resources in the United States. The Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) program (initiated in 1975) was one of nine components of NURE. Planned systematic sampling of the entire United States began in 1976 under the responsibility of four DOE national laboratories: Lawrence Livermore Laboratory (LLL), Los Alamos Scientific Laboratory (LASL), Oak Ridge Gaseous Diffusion Plant (ORGDP), and Savannah River Laboratory (SRL). The NURE program effectively ended about 1983-84 when funding disappeared. Out of a total of 625 quadrangles that cover the entire lower 48 States and Alaska, only 307 quadrangles were completely sampled, some were partially completed, and many had not been done at all. Over the years various efforts have been made to finish the original task or analyze the stored samples or complete final reports. The sample archive was transferred to the U.S. Geological Survey (USGS) in 1985. The archive reportedly contained about 380,000 original sediment samples from all four laboratories, about 250,000 replicates, splits, size fractions or other samples and approximately 500,000 resin samples of waters.

  10. Mineralogical textural and compositional data on the alteration of basaltic glass from Kilauea, Hawaii to 300 degrees C: Insights to the corrosion of a borosilicate glass waste-form. [Yucca Mountain Project

    SciTech Connect

    Smith, D.K.

    1990-01-01

    Mineralogical, textural and compositional data accompanying greenschist facies metamorphism (to 300{degrees}C) of basalts of the East Rift Zone (ERZ), Kilauea, Hawaii may be evaluated relative to published and experimental results for the surface corrosion of borosilicate glass. The ERZ alteration sequence is dominated by intermittent palagonite, interlayered smectite-chlorite, chlorite, and actinolite-epidote-anhydrite. Alteration is best developed in fractures and vesicles where surface reaction layers root on the glass matrix forming rinds in excess of 100 microns thick. Fractures control fluid circulation and the alteration sequence. Proximal to the glass surface, palagonite, Fe-Ti oxides and clays replace fresh glass as the surface reaction layer migrates inwards; away from the surface, amphibole, anhydrite, quartz and calcite crystallize from hydrothermal fluids in contact with the glass. The texture and composition of basaltic glass surfaces are similar to those of a SRL-165 glass leached statically for sixty days at 150 {degrees}C. While the ERZ reservoir is a complex open system, conservative comparisons between the alteration of ERZ and synthetic borosilicate glass are warranted. 31 refs., 2 figs.

  11. Simulation of natural corrosion by vapor hydration test: seven-year results

    SciTech Connect

    Luo, J.S.; Ebert, W.L.; Mazer, J.J.; Bates, J.K.

    1996-12-31

    We have investigated the alteration behavior of synthetic basalt and SRL 165 borosilicate waste glasses that had been reacted in water vapor at 70 {degrees}C for time periods up to seven years. The nature and extent of corrosion of glasses have been determined by characterizing the reacted glass surface with optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive x-ray spectroscopy (EDS). Alteration in 70 {degrees}C laboratory tests was compared to that which occurs at 150-200 {degrees}C and also with Hawaiian basaltic glasses of 480 to 750 year old subaerially altered in nature. Synthetic basalt and waste glasses, both containing about 50 percent wt SiO{sub 2} were found to react with water vapor to form an amorphous hydrated gel that contained small amounts of clay, nearly identical to palagonite layers formed on naturally altered basaltic glass. This result implies that the corrosion reaction in nature can be simulated with a vapor hydration test. These tests also provide a means for measuring the corrosion kinetics, which are difficult to determine by studying natural samples because alteration layers have often spelled off the samples and we have only limited knowledge of the conditions under which alteration occurred.

  12. Dissolution of ion exchange resin by hydrogen peroxide

    SciTech Connect

    Lee, S.C.

    1981-08-01

    The resin dissolution process was conducted successfully in full-scale equipment at the SRL Semiworks. A solution containing 0.001M Fe/sup 2 +/, or Fe/sup 3 +/, and 3 vol % H/sub 2/O/sub 2/ in 0.1M HNO/sub 3/ is sufficient to dissolve up to 40 vol % resin slurry (Dowex 50W-X8). Foaming and pressurization can be eliminated by maintaining the dissolution temperature below 99/sup 0/C. The recommended dissolution temperature range is 85 to 90/sup 0/C. Premixing hydrogen peroxide with all reactants will not create a safety hazard, but operating with a continual feed of hydrogen peroxide is recommended to control the dissolution rate. An air sparging rate of 1.0 to 1.5 scfm will provide sufficient mixing. Spent resin from chemical separation contains DTPA (diethylenetriaminepentaacetic acid) residue, and the resin must be washed with 0.1M NH/sub 4/ OH to remove excess DTPA before dissolution. Gamma irradiation of resin up to 4 kW-hr/L did not change the dissolution rate significantly.

  13. Asotin Creek Instream Habitat Alteration Projects : Habitat Evaluation, Adult and Juvenile Habitat Utilization and Water Temperature Monitoring : 2001 Progress Report.

    SciTech Connect

    Bumgarner, Joseph D.

    2002-01-01

    projects to improve fish habitat. In 1998, the ACCD identified the need for a more detailed analysis of these instream projects to fully evaluate their effectiveness at improving fish habitat. Therefore, ACCD contracted with WDFW's Snake River Lab (SRL) to take pre- and post-construction measurements of the habitat (i.e., pools, LOD, width, depth) at each site, and to evaluate fish use within some of the altered sites. These results have been published annually as progress reports to the ACCD (Bumgarner et al. 1999, Wargo et al. 2000, and Bumgarner and Schuck 2001). The ACCD also contracted with the WDFW SRL to conduct other evaluation and monitoring in the stream such as: (1) conduct snorkel surveys at habitat alteration sites to document fish usage following construction, (2) deploy temperature monitors throughout the basin to document summer water temperatures, and (3) attempt to document adult fish utilization by documenting the number of steelhead redds associated with habitat altered areas. This report provides a summary of pre-construction measurements taken on three proposed Charley Creek habitat sites during 2001, two sites in main Asotin Creek, and one site in George Creek, a tributary that enters in the lower Asotin Creek basin. Further, it provides a comparison of measurements taken pre- and post-construction on three 1999 habitat sites taken two years later, but at similar river flows. It also presents data collected from snorkel surveys, redd counts, and temperature monitoring.

  14. Quantifying Silica Reactivity in Subsurface Environments: Reaction Affinity and Solute Matrix Controls on Quartz and SiO2 Glass Dissolution Kinetics

    SciTech Connect

    Patricia M. Dove

    2000-12-13

    During the three years of this project, Professor Dove's laboratory made tremendous progress in understanding controls on amorphous silica dissolution kinetics in aqueous solutions. Our findings have already received considerable attention. In hydrothermal and low temperature studies, the work focused on determining quantitative and mechanistic controls on the most abundant silica polymorphs in Earth environments--quartz and amorphous silica. Our studies achieved goals set forth in the original proposal to establish a new quantitative understanding of amorphous silica dissolution. This support has resulted in 10 journal, 12 abstracts and 2 thesis publications. The PI and students were also recognized with 6 awards during this period. The 1998 EMSP conference in Chicago was an important meeting for our project. The symposium, enabled P.I. Dove to establish valuable contacts with ''users'' having specific needs for the findings of our EMSP project related to the urgency of problems in the Tanks Focus Area (TFA). Since that time, our working relations developed as Dove interacted with TFA scientists and engineers on the problems of waste glass properties. These interactions refined our experimental objectives to better meet their needs. Dove presented the results of EMSP research findings to a TFA subgroup at a Product Acceptance Workshop held in Salt Lake City during December 1998. The travel costs to attend this unanticipated opportunity were paid from EMSP project funds. In January 2000, Dove also attended a similar meeting in Atlanta with PNNL, SRL and BNF scientists/engineers to discuss new issues and make another level of decisions on the Product Acceptance goals. Our EMSP-funded research interfaced very well with the ongoing studies of Dr. Pete McGrail and colleagues in the Applied Geochemistry Group at PNNL. The value of our work to ''users'' was further demonstrated when Dove's EMSP-funded Postdoc, Dr. Jonathan Icenhower was hired by the same PNNL group. With

  15. How Much Can the Total Aleatory Variability of Empirical Ground Motion Prediction Equations Be Reduced Using Physics-Based Earthquake Simulations?

    NASA Astrophysics Data System (ADS)

    Jordan, T. H.; Wang, F.; Graves, R. W.; Callaghan, S.; Olsen, K. B.; Cui, Y.; Milner, K. R.; Juve, G.; Vahi, K.; Yu, J.; Deelman, E.; Gill, D.; Maechling, P. J.

    2015-12-01

    Ground motion prediction equations (GMPEs) in common use predict the logarithmic intensity of ground shaking, lnY, as a deterministic value, lnYpred(x), conditioned on a set of explanatory variables x plus a normally distributed random variable with a standard deviation σT. The latter accounts for the unexplained variability in the ground motion data used to calibrate the GMPE and is typically 0.5-0.7 in natural log units. Reducing this residual or "aleatory" variability is a high priority for seismic hazard analysis, because the probabilities of exceedance at high Y values go up rapidly with σT. adding costs to the seismic design of critical facilities to account for the prediction uncertainty. However, attempts to decrease σT by incorporating more explanatory variables to the GMPEs have been largely unsuccessful (e.g., Strasser et al., SRL, 2009). An alternative is to employ physics-based earthquake simulations that properly account for source directivity, basin effects, directivity-basin coupling, and other 3D complexities. We have explored the theoretical limits of this approach through an analysis of large (> 108) ensembles of 3D synthetic seismograms generated for the Los Angeles region by SCEC's CyberShake project using the new tool of averaging-based factorization (ABF, Wang & Jordan, BSSA, 2014). The residual variance obtained by applying GMPEs to the CyberShake dataset matches the frequency-dependence of σT obtained for the GMPE calibration dataset. The ABF analysis allows us to partition this variance into uncorrelated components representing source, path, and site effects. We show that simulations can potentially reduce σT by about one-third, which could lower the exceedance probabilities for high hazard levels at fixed x by orders of magnitude. Realizing this gain in forecasting probability would have a broad impact on risk-reduction strategies, especially for critical facilities such as large dams, nuclear power plants, and energy transportation

  16. Msa1 and Msa2 Modulate G1-Specific Transcription to Promote G1 Arrest and the Transition to Quiescence in Budding Yeast

    PubMed Central

    Miles, Shawna; Croxford, Matthew W.; Abeysinghe, Amali P.; Breeden, Linda L.

    2016-01-01

    Yeast that naturally exhaust their glucose source can enter a quiescent state that is characterized by reduced cell size, and high cell density, stress tolerance and longevity. The transition to quiescence involves highly asymmetric cell divisions, dramatic reprogramming of transcription and global changes in chromatin structure and chromosome topology. Cells enter quiescence from G1 and we find that there is a positive correlation between the length of G1 and the yield of quiescent cells. The Swi4 and Swi6 transcription factors, which form the SBF transcription complex and promote the G1 to S transition in cycling cells, are also critical for the transition to quiescence. Swi6 forms a second complex with Mbp1 (MBF), which is not required for quiescence. These are the functional analogues of the E2F complexes of higher eukaryotes. Loss of the RB analogue, Whi5, and the related protein Srl3/Whi7, delays G1 arrest, but it also delays recovery from quiescence. Two MBF- and SBF-Associated proteins have been identified that have little effect on SBF or MBF activity in cycling cells. We show that these two related proteins, Msa1 and Msa2, are specifically required for the transition to quiescence. Like the E2F complexes that are quiescence-specific, Msa1 and Msa2 are required to repress the transcription of many SBF target genes, including SWI4, the CLN2 cyclin and histones, specifically after glucose is exhausted from the media. They also activate transcription of many MBF target genes. msa1msa2 cells fail to G1 arrest and rapidly lose viability upon glucose exhaustion. msa1msa2 mutants that survive this transition are very large, but they attain the same thermo-tolerance and longevity of wild type quiescent cells. This indicates that Msa1 and Msa2 are required for successful transition to quiescence, but not for the maintenance of that state. PMID:27272642

  17. A strategy for weapons-grade plutonium disposition

    SciTech Connect

    Sylvester, K.W.B.

    1994-09-01

    A political as well as technical analysis was performed to determine the feasibility of glassification (vitrification) for weapons grade plutonium (WGPu) disposition. The political analysis provided the criteria necessary to compare alternative storage forms. The technical areas of weapon useability and environmental safety were then computationally and experimentally explored and a vitrification implementation strategy postulated. The Monte Carlo Neutron Photon (MCNP) computer code was used to model the effect of blending WGPu with reactor grade Pu (RGPu). A mixture of 30% RGPu and 70% WGPu more than doubled the surface flux from a bare sphere of the mixture which assumedly correlates to a significantly increased predetonation probability. Rare earth diluents were also examined (using MCNP) for their ability to increase the compressed critical mass of the WGPu mixture. The rare earths (notably Eu) were effective in this regard. As Pu-239 has a 24,100 year half life, reactivity control in the long term is an environmental safety issue. Rare earths were investigated as criticality controllers due to their neutron absorption capabilities and insolubility in aqueous environments. Thorium (a Pu surrogate) and the rare earths Eu, Gd, and Sm were added to two standard frits (ARM-1 and SRL-165) and formed into glass. Aqueous leach tests were performed (using MCC-1P guidelines) to measure rare earth leaching and determine the added elements` effects on glass durability. Europium was much more leach resistant than boron in the glasses tested. The elements had no negative effect on the environmental durability of the glasses tested at 90 C and minimal effect at room temperature. No fission product releases were detected in the ARM-1 compositions (which contained numerous simulated fission products).

  18. Secreted Matrix Metalloproteinase-9 of Proliferating Smooth Muscle Cells as a Trigger for Drug Release from Stent Surface Polymers in Coronary Arteries.

    PubMed

    Gliesche, Daniel G; Hussner, Janine; Witzigmann, Dominik; Porta, Fabiola; Glatter, Timo; Schmidt, Alexander; Huwyler, Jörg; Meyer Zu Schwabedissen, Henriette E

    2016-07-05

    Cardiovascular diseases are the leading causes of death in industrialized countries. Atherosclerotic coronary arteries are commonly treated with percutaneous transluminal coronary intervention followed by stent deployment. This treatment has significantly improved the clinical outcome. However, triggered vascular smooth muscle cell (SMC) proliferation leads to in-stent restenosis in bare metal stents. In addition, stent thrombosis is a severe side effect of drug eluting stents due to inhibition of endothelialization. The aim of this study was to develop and test a stent surface polymer, where cytotoxic drugs are covalently conjugated to the surface and released by proteases selectively secreted by proliferating smooth muscle cells. Resting and proliferating human coronary artery smooth muscle cells (HCASMC) and endothelial cells (HCAEC) were screened to identify an enzyme exclusively released by proliferating HCASMC. Expression analyses and enzyme activity assays verified selective and exclusive activity of the matrix metalloproteinase-9 (MMP-9) in proliferating HCASMC. The principle of drug release exclusively triggered by proliferating HCASMC was tested using the biodegradable stent surface polymer poly-l-lactic acid (PLLA) and the MMP-9 cleavable peptide linkers named SRL and AVR. The specific peptide cleavage by MMP-9 was verified by attachment of the model compound fluorescein. Fluorescein release was observed in the presence of MMP-9 secreting HCASMC but not of proliferating HCAEC. Our findings suggest that cytotoxic drug conjugated polymers can be designed to selectively release the attached compound triggered by MMP-9 secreting smooth muscle cells. This novel concept may be beneficial for stent endothelialization thereby reducing the risk of restenosis and thrombosis.

  19. Endotoxinemia and benzodiazepine-like substances in compensated cirrhotic patients: a randomized study comparing the effect of rifaximine alone and in association with a symbiotic preparation.

    PubMed

    Lighthouse, J.; Naito, Y.; Helmy, A.; Hotten, P.; Fuji, H.; Min, C.H.; Yoshioka, M.; Marotta, F.

    2004-03-01

    Aim: The aim of the present investigation was to test study benzodiazepines (BZDs) profile in patients with viral cirrhosis under different combinations of rifaximine and of a novel symbiotic. Methods: Our study groups consisted of 30 patients with a confirmed diagnosis of HCV-related Child B liver cirrhosis. Patients were randomly allocated into three groups: rifaximine 400mg t.i.d. for 2 weeks; (B) SCM-III (Lactobacillus acidophilus, Lactobacillus helveticus and Bifidobacteria in a ion- and vitamin-enriched medium, Named srl, Italy) 10ml t.i.d. for 2 weeks; (C) rifaximine 400mg t.i.d. for 1 week followed by SCM-III 10ml t.i.d. for 5 weeks. At weekly interval, blood samples were withdrawn to test BZD-like substances, ammonia and endotoxin. Results: Rifaximine treatment brought about a significant early drop of BZDs ( [Formula: see text] versus pre-treatment and versus control) till fourth week of observation when a gradual increase took place with return to pre-treatment values at the sixth week. Symbiotic treatment was comparably effective while given to patients but significantly elevated BZDs level were noted starting from the third week. Similar phenomena were noted for endotoxin and ammonia although symbiotic seemed more effective against endotoxin and rifaximine against ammonia increase. However, the sequential treatment rifaximine-symbiotic brought about a sustained normalization of BZDs, ammonia and endotoxin throughout the 6-week study. Conclusion: The present pilot study suggests that a rifaximine-symbiotic regimen could be an effective tool in compensated liver cirrhosis to limit some triggering factors of hepatic encephalopathy while being amenable to long-term use and devoid of significant side effects.

  20. An olive oil-derived antioxidant mixture ameliorates the age-related decline of skeletal muscle function.

    PubMed

    Pierno, Sabata; Tricarico, Domenico; Liantonio, Antonella; Mele, Antonietta; Digennaro, Claudio; Rolland, Jean-François; Bianco, Gianpatrizio; Villanova, Luciano; Merendino, Alessandro; Camerino, Giulia Maria; De Luca, Annamaria; Desaphy, Jean-François; Camerino, Diana Conte

    2014-02-01

    Age-related skeletal muscle decline is characterized by the modification of sarcolemma ion channels important to sustain fiber excitability and to prevent metabolic dysfunction. Also, calcium homeostasis and contractile function are impaired. In the aim to understand whether these modifications are related to oxidative damage and can be reverted by antioxidant treatment, we examined the effects of in vivo treatment with an waste water polyphenolic mixture (LACHI MIX HT) supplied by LACHIFARMA S.r.l. Italy containing hydroxytirosol (HT), gallic acid, and homovanillic acid on the skeletal muscles of 27-month-old rats. After 6-week treatment, we found an improvement of chloride ClC-1 channel conductance, pivotal for membrane electrical stability, and of ATP-dependent potassium channel activity, important in coupling excitability with fiber metabolism. Both of them were analyzed using electrophysiological techniques. The treatment also restored the resting cytosolic calcium concentration, the sarcoplasmic reticulum calcium release, and the mechanical threshold for contraction, an index of excitation-contraction coupling mechanism. Muscle weight and blood creatine kinase levels were preserved in LACHI MIX HT-treated aged rats. The antioxidant activity of LACHI MIX HT was confirmed by the reduction of malondialdehyde levels in the brain of the LACHI MIX HT-treated aged rats. In comparison, the administration of purified HT was less effective on all the parameters studied. Although muscle function was not completely recovered, the present study provides evidence of the beneficial effects of LACHI MIX HT, a natural compound, to ameliorate skeletal muscle functional decline due to aging-associated oxidative stress.

  1. Effect of Root System Morphology on Root-sprouting and Shoot-rooting Abilities in 123 Plant Species from Eroded Lands in North-east Spain

    PubMed Central

    GUERRERO-CAMPO, JOAQUÍN; PALACIO, SARA; PÉREZ-RONTOMÉ, CARMEN; MONTSERRAT-MARTÍ, GABRIEL

    2006-01-01

    • Background and Aims The objective of this study was to test whether the mean values of several root morphological variables were related to the ability to develop root-borne shoots and/or shoot-borne roots in a wide range of vascular plants. • Methods A comparative study was carried out on the 123 most common plant species from eroded lands in north-east Spain. After careful excavations in the field, measurements were taken of the maximum root depth, absolute and relative basal root diameter, specific root length (SRL), and the root depth/root lateral spread ratio on at least three individuals per species. Shoot-rooting and root-sprouting were observed in a large number of individuals in many eroded and sedimentary environments. The effect of life history and phylogeny on shoot-rooting and root-sprouting abilities was also analysed. • Key Results The species with coarse and deep tap-roots tended to be root-sprouting and those with fine, fasciculate and long main roots (which generally spread laterally), tended to be shoot-rooting. Phylogeny had an important influence on root system morphology and shoot-rooting and root-sprouting capacities. However, the above relations stood after applying analyses based on phylogenetically independent contrasts (PICs). • Conclusions The main morphological features of the root system of the study species are related to their ability to sprout from their roots and form roots from their shoots. According to the results, such abilities might only be functionally viable in restricted root system morphologies and ecological strategies. PMID:16790468

  2. Metabolic consequences of modern immunosuppressive agents in solid organ transplantation

    PubMed Central

    Bamgbola, Oluwatoyin

    2016-01-01

    Among other factors, sophistication of immunosuppressive (IS) regimen accounts for the remarkable success attained in the short- and medium-term solid organ transplant (SOT) survival. The use of steroids, mycophenolate mofetil and calcineurin inhibitors (CNI) have led to annual renal graft survival rates exceeding 90% in the last six decades. On the other hand, attrition rates of the allograft beyond the first year have remained unchanged. In addition, there is a persistent high cardiovascular (CV) mortality rate among transplant recipients with functioning grafts. These shortcomings are in part due to the metabolic effects of steroids, CNI and sirolimus (SRL), all of which are implicated in hypertension, new onset diabetes after transplant (NODAT), and dyslipidemia. In a bid to reduce the required amount of harmful maintenance agents, T-cell-depleting antibodies are increasingly used for induction therapy. The downsides to their use are greater incidence of opportunistic viral infections and malignancy. On the other hand, inadequate immunosuppression causes recurrent rejection episodes and therefore early-onset chronic allograft dysfunction. In addition to the adverse metabolic effects of the steroid rescue needed in these settings, the generated proinflammatory milieu may promote accelerated atherosclerotic disorders, thus setting up a vicious cycle. The recent availability of newer agent, belatacept holds a promise in reducing the incidence of metabolic disorders and hopefully its long-term CV consequences. Although therapeutic drug monitoring as applied to CNI may be helpful, pharmacodynamic tools are needed to promote a customized selection of IS agents that offer the most benefit to an individual without jeopardizing the allograft survival. PMID:27293540

  3. Patterns in root traits of woody species hosting arbuscular and ectomycorrhizas: implications for the evolution of belowground strategies.

    PubMed

    Comas, Louise H; Callahan, Hilary S; Midford, Peter E

    2014-08-01

    Root traits vary enormously among plant species but we have little understanding of how this variation affects their functioning. Of central interest is how root traits are related to plant resource acquisition strategies from soil. We examined root traits of 33 woody species from northeastern US forests that form two of the most common types of mutualisms with fungi, arbuscular mycorrhizas (AM) and ectomycorrhizas (EM). We examined root trait distribution with respect to plant phylogeny, quantifying the phylogenetic signal (K statistic) in fine root morphology and architecture, and used phylogenetically independent contrasts (PICs) to test whether taxa forming different mycorrhizal associations had different root traits. We found a pattern of species forming roots with thinner diameters as species diversified across time. Given moderate phylogenetic signals (K = 0.44-0.68), we used PICs to examine traits variation among taxa forming AM or EM, revealing that hosts of AM were associated with lower branching intensity (r PIC = -0.77) and thicker root diameter (r PIC = -0.41). Because EM evolved relatively more recently and intermittently across plant phylogenies, significant differences in root traits and colonization between plants forming AM and EM imply linkages between the evolution of these biotic interactions and root traits and suggest a history of selection pressures, with trade-offs for supporting different types of associations. Finally, across plant hosts of both EM and AM, species with thinner root diameters and longer specific root length (SRL) had less colonization (r PIC = 0.85, -0.87), suggesting constraints on colonization linked to the evolution of root morphology.

  4. Summary report on four foot septifoil cooling experiment

    SciTech Connect

    Randolph, H.W.; Collins, S.L.; Verebelyi, D.T.; Foti, D.J.

    1991-10-01

    Cooling parameters for some of the SRS reactor internal components are computed using the Transient Reactor Analysis Code, TRAC.'' In order to benchmark the code, the Safety Analysis Group of SRL requested an experiment to provide measurements of cooling parameters in a well defined physical system utilizing SRS reactor component(s). The experiment selected included a short length of septifoil with both top and bottom fittings containing five simulated control rods in an unseated'' configuration. Power level to be supplied to the rods was targeted at 2.5 kilowatts per foot. The septifoil segment was to be operated with no forced flow in order to evaluate thermal-hydraulic cooling. Parameters to be measured for comparison with code predictions were basic cooling phenomena, incidence of film boiling, thermal-hydraulic flow rate, pressure rise, and ratio of heat transfer through the wall of the assembly vs heat transfer to axial water flow through the assembly. Experimental apparatus was designed and assembled incorporating five simulated control rods four feet long, joule heated inside a five foot length of type Q'' septifoil. Water at 70 C was fed independently to the bottom inlet and along the outside of the septifoil. Water flowing along the outside of the septifoil was in confined flow and provided calorimetry to measure power flow through the septifoil housing. A shadowgraph technique was developed and used to monitor unforced flow of water pumped thermal-hydraulically through the septifoil. Electrical power of 10,000 to 70,000 watts was fed to the simulated rods from a dc power supply. Computer data acquisition was accomplished using LabView'' software programmed to match the configuration of the experiment along with scanning digital voltmeters and requisite signal sensors. Video camcorders were used to provide video records of six areas of the experiment.

  5. Summary report on four foot septifoil cooling experiment

    SciTech Connect

    Randolph, H.W.; Collins, S.L.; Verebelyi, D.T.; Foti, D.J.

    1991-10-01

    Cooling parameters for some of the SRS reactor internal components are computed using the Transient Reactor Analysis Code, ``TRAC.`` In order to benchmark the code, the Safety Analysis Group of SRL requested an experiment to provide measurements of cooling parameters in a well defined physical system utilizing SRS reactor component(s). The experiment selected included a short length of septifoil with both top and bottom fittings containing five simulated control rods in an ``unseated`` configuration. Power level to be supplied to the rods was targeted at 2.5 kilowatts per foot. The septifoil segment was to be operated with no forced flow in order to evaluate thermal-hydraulic cooling. Parameters to be measured for comparison with code predictions were basic cooling phenomena, incidence of film boiling, thermal-hydraulic flow rate, pressure rise, and ratio of heat transfer through the wall of the assembly vs heat transfer to axial water flow through the assembly. Experimental apparatus was designed and assembled incorporating five simulated control rods four feet long, joule heated inside a five foot length of type ``Q`` septifoil. Water at 70 C was fed independently to the bottom inlet and along the outside of the septifoil. Water flowing along the outside of the septifoil was in confined flow and provided calorimetry to measure power flow through the septifoil housing. A shadowgraph technique was developed and used to monitor unforced flow of water pumped thermal-hydraulically through the septifoil. Electrical power of 10,000 to 70,000 watts was fed to the simulated rods from a dc power supply. Computer data acquisition was accomplished using ``LabView`` software programmed to match the configuration of the experiment along with scanning digital voltmeters and requisite signal sensors. Video camcorders were used to provide video records of six areas of the experiment.

  6. Patterns in root traits of woody species hosting arbuscular and ectomycorrhizas: implications for the evolution of belowground strategies

    PubMed Central

    Comas, Louise H; Callahan, Hilary S; Midford, Peter E

    2014-01-01

    Root traits vary enormously among plant species but we have little understanding of how this variation affects their functioning. Of central interest is how root traits are related to plant resource acquisition strategies from soil. We examined root traits of 33 woody species from northeastern US forests that form two of the most common types of mutualisms with fungi, arbuscular mycorrhizas (AM) and ectomycorrhizas (EM). We examined root trait distribution with respect to plant phylogeny, quantifying the phylogenetic signal (K statistic) in fine root morphology and architecture, and used phylogenetically independent contrasts (PICs) to test whether taxa forming different mycorrhizal associations had different root traits. We found a pattern of species forming roots with thinner diameters as species diversified across time. Given moderate phylogenetic signals (K = 0.44–0.68), we used PICs to examine traits variation among taxa forming AM or EM, revealing that hosts of AM were associated with lower branching intensity (rPIC = −0.77) and thicker root diameter (rPIC = −0.41). Because EM evolved relatively more recently and intermittently across plant phylogenies, significant differences in root traits and colonization between plants forming AM and EM imply linkages between the evolution of these biotic interactions and root traits and suggest a history of selection pressures, with trade-offs for supporting different types of associations. Finally, across plant hosts of both EM and AM, species with thinner root diameters and longer specific root length (SRL) had less colonization (rPIC = 0.85, −0.87), suggesting constraints on colonization linked to the evolution of root morphology. PMID:25247056

  7. Platinum-RNA modifications following drug treatment in S. cerevisiae identified by click chemistry and enzymatic mapping.

    PubMed

    Osborn, Maire F; White, Jonathan D; Haley, Michael M; DeRose, Victoria J

    2014-10-17

    With the importance of RNA-based regulatory pathways, the potential for targeting noncoding and coding RNAs by small molecule therapeutics is of great interest. Platinum(II) complexes including cisplatin (cis-diamminedichloroplatinum(II)) are widely prescribed anticancer compounds that form stable adducts on nucleic acids. In tumors, DNA damage from Pt(II) initiates apoptotic signaling, but this activity is not necessary for cytotoxicity (e.g., Yu et al., 2008), suggesting accumulation and consequences of Pt(II) lesions on non-DNA targets. We previously reported an azide-functionalized compound, picazoplatin, designed for post-treatment click labeling that enables detection of Pt complexes (White et al., 2013). Here, we report in-gel fluorescent detection of Pt-bound rRNA and tRNA extracted from picazoplatin-treated S. cerevisiae and labeled using Cu-free click chemistry. These data provide the first evidence that cellular tRNA is a platinum drug substrate. We assess Pt(II) binding sites within rRNA from cisplatin-treated S. cerevisiae, in regions where damage is linked to significant downstream consequences including the sarcin-ricin loop (SRL) Helix 95. Pt-RNA adducts occur on the nucleotide substrates of ribosome-inactivating proteins, as well as on the bulged-G motif critical for elongation factor recognition of the loop. At therapeutically relevant concentrations, Pt(II) also binds robustly within conserved cation-binding pockets in Domains V and VI rRNA at the peptidyl transferase center. Taken together, these results demonstrate a convenient click chemistry methodology that can be applied to identify other metal or covalent modification-based drug targets and suggest a ribotoxic mechanism for cisplatin cytotoxicity.

  8. Direct determination of 90Sr and 147Pm in Chernobyl hot particles collected in Kiev using beta absorption method.

    PubMed

    Papp, Z; Bolyós, A; Dezsó, Z; Daróczy, S

    1997-12-01

    59 hot particles were collected in Kiev, Ukraine, in 1987. All but one were prepared from a moss carpet of 360 cm2 area. Radionuclide composition of the hot particles was investigated by gamma-spectrometry and beta absorption method. Pure beta emitters 90Sr and 147Pm were determined in 25 hot particles measuring the beta absorption curves of the hot particles with an end-window Geiger-Müller counter and decomposing the curves in order to obtain the contributions of 90Sr and 147Pm to the total beta counting rate. All but one of the hot particles were found to be the debris of the fuel. The activity ratio 90Sr:l44Ce was 0.052 in good agreement with theoretical calculations on core inventories. This means that strontium behaved as a nonvolatile element in the process of the formation of the hot particles investigated. The activity ratio 147Pm:144Ce was 0.078 which is half of the theoretical result. Although 147Pm is considered to be a refractory nuclide, it seems that significant part of 147Pm went to the homogeneous fraction of the general fallout. The surface density of hot particles (of higher than about 50 Bq activity) was about 1,600 m(-2) and that of the activities of the nuclides 90Sr, 106Ru, 134Cs, 137Cs, 144Ce and 147Pm as components of hot particles was 12.2, 54.3, 5.9, 9.7, 234 and 18.3 kBq m(-2) (activity values counted for 26 April 1986), respectively, in downtown Kiev city in 1987.

  9. Identifying potential PARIS homologs in D. melanogaster.

    PubMed

    Merzetti, E M; Staveley, B E

    2016-11-03

    Mitochondrial destruction leads to the formation of reactive oxygen species, increases cellular stress, causes apoptotic cell death, and involves a cascade of proteins including PARKIN, PINK1, and Mitofusin2. Mitochondrial biogenesis pathways depend upon the activity of the protein PGC-1α. These two processes are coordinated by the activity of a transcriptional repressor, Parkin interacting substrate (PARIS). The PARIS protein is degraded through the activity of the PARKIN protein, which in turn eliminates the transcriptional repression that PARIS imposes upon a downstream target, PGC-1α. Genes in this pathway have been implicated in Parkinson's disease, and there is a strong relationship between mitochondrial dysfunction and pre-mature neuron death. The identification of a PARIS homolog in Drosophila melanogaster would increase our understanding of the roles that PARIS and interacting genes play in higher organisms. We identified three potential PARIS homologs in D. melanogaster, one of which encodes a protein with similar domains to the Homo sapiens PARIS protein, CG15436. The Drosophila eye is formed from neuronal precursors, making it an ideal system to assay the effects of altered gene expression on neuronal tissue formation. The eye-specific expression of RNAi constructs for these genes revealed that both CG15269 and Crol caused neurodegenerative phenotypes, whereas CG15436 produced a phenotype similar to srl-EY. Crol-RNAi expression reduced mean lifespan when expressed in dopaminergic neurons, whereas CG15436-RNAi significantly increased lifespan. CG15436 was PARIS-like in both structure and function, and we characterized the effects of decreased gene expression in both the neuron-rich D. melanogaster eye and in dopaminergic neurons.

  10. Semiconductor ring lasers as optical neurons

    NASA Astrophysics Data System (ADS)

    Coomans, W.; Gelens, L.; Mashal, L.; Beri, S.; Van der Sande, G.; Danckaert, J.; Verschaffelt, G.

    2012-06-01

    Semiconductor Ring Lasers (SRLs) are a modern class of semiconductor lasers whose active cavity is characterized by a circular geometry. This enables the laser to support two counterpropagating modes, referred to as the clockwise (CW) and the counterclockwise (CCW) mode. Semiconductor ring lasers have been shown to have a regime of operation in which they are excitable, when the linear coupling between the counterpropagating modes is asymmetric. This can be achieved by increasing the reflection of, for example, the CW mode into the CCW mode. This will stabilize lasing in the CCW mode. In the excitable regime, the SRL will fire optical pulses (spikes) in the CW mode as a response to noise perturbations. In this contribution we experimentally and theoretically characterize these spikes. Our experiments reveal a statistical distribution of the characteristics of the optical pulses that is not observed in regular excitable systems. In particular, an inverse correlation exists between the pulse amplitude and duration. Numerical simulations and an interpretation in an asymptotic phase space confirm and explain these experimentally observed pulse characteristics [L. Gelens et al., Phys. Rev. A 82 063841, 2010]. We will also theoretically consider asymmetric SRLs coupled through a single bus waveguide. This is a first step towards an integrated optical neural network using semiconductor ring lasers as building blocks. We will show that for weak coupling, excitatory excursions still persist due to the similar phase space structure. Moreover, the coupled SRLs can excite pulses in each other and can thus function as communicating neurons [W. Coomans et al., Phys. Rev. E 84 036209, 2011]. This type of neural network can be fully integrated on chip and does not suffer from the drawback of needing extra-cavity measures, such as optical injection or saturable absorbers.

  11. Root morphological responses of three hot pepper cultivars to Cd exposure and their correlations with Cd accumulation.

    PubMed

    Huang, Baifei; Xin, Junliang; Dai, Hongwen; Liu, Aiqun; Zhou, Wenjing; Yi, Yumei; Liao, Kebing

    2015-01-01

    Cultivars of hot pepper (Capsicum annuum L.) differ widely in their fruit cadmium (Cd) concentrations. Previously, we suggested that low-Cd cultivars are better able to prevent the translocation of Cd from roots to aboveground parts, but the corresponding mechanisms are still unknown. In this study, we aimed to improve understanding of the root morphological characteristics of the mechanisms involved in two low-Cd and a high-Cd cultivar. Seedlings were grown in nutrient solutions containing 0 (control), 2, and 10 μM Cd for 20 days, and Cd contents for the three cultivars were compared with changes in root morphology. The total root length (RL), root surface area (SA), number of root tips (RT), and specific root length (SRL) of all cultivars were decreased significantly by the 10 μM Cd treatment with the exception of the SA in JFZ, which showed no obvious change. For each cultivar, the 10 μM Cd treatment decreased significantly RL and SA specifically in roots with diameters (RD) of RD ≤ 0.2 mm or 0.2 mm < RD ≤ 0.4 mm, and increased significantly RL and SA specifically in roots with diameters of 0.6 mm < RD ≤ 0.8 mm. Hot pepper cultivars differ greatly in Cd accumulation and root morphology. In the 10 μM Cd treatment, root volume (RV), SA, and RT of all cultivars were negatively correlated with Cd concentration and amount in roots. However, RL, SA, RV, and RT of all cultivars were positively correlated with Cd concentration and amount in shoots, and translocation rate of Cd. The two low-Cd cultivars of hot pepper had less root tips, shorter root length, and smaller root surface area than the high-Cd cultivar in 10 μM Cd treatment, which may play a vital role in reducing root-to-shoot Cd translocation.

  12. Asotin Creek Instream Habitat Alteration Projects: 1998 Habitat Evaluation Surveys.

    SciTech Connect

    Bumgarner, Joseph D.

    1999-03-01

    The Asotin Creek Model Watershed Master Plan was completed 1994. The plan was developed by a landowner steering committee for the Asotin County Conservation District (ACCD), with technical support from the various Federal, State and local entities. Actions identified within the plan to improve the Asotin Creek ecosystem fall into four main categories, (1) Stream and Riparian, (2) Forestland, (3) Rangeland, and (4) Cropland. Specific actions to be carried out within the stream and in the riparian area to improve fish habitat were, (a) create more pools, (b) increase the amount of large organic debris (LOD), (c) increase the riparian buffer zone through tree planting, and (d) increase fencing to limit livestock access; additionally, the actions are intended to stabilize the river channel, reduce sediment input, and protect private property. Fish species of main concern in Asotin Creek are summer steelhead (Oncorhynchus mykiss), spring chinook (Oncorhynchus tshawytscha), and bull trout (Salvelinus confluentus). Spring chinook in Asotin Creek are considered extinct (Bumgarner et al. 1998); bull trout and summer steelhead are below historical levels and are currently as ''threatened'' under the ESA. In 1998, 16 instream habitat projects were planned by ACCD along with local landowners. The ACCD identified the need for a more detailed analysis of these instream projects to fully evaluate their effectiveness at improving fish habitat. The Washington Department of Fish and Wildlife's (WDFW) Snake River Lab (SRL) was contracted by the ACCD to take pre-construction measurements of the existing habitat (pools, LOD, width, depth, etc.) within each identified site, and to eventually evaluate fish use within these sites. All pre-construction habitat measurements were completed between 6 and 14 July, 1998. 1998 was the first year that this sort of evaluation has occurred. Post construction measurements of habitat structures installed in 1998, and fish usage evaluation, will be

  13. Raman Lidar Measurements of Aerosol Extinction and Backscattering. Report 2; Derivation of Aerosol Real Refractive Index, Single-Scattering Albedo, and Humidification Factor using Raman Lidar and Aircraft Size Distribution

    NASA Technical Reports Server (NTRS)

    Ferrare, R. A.; Melfi, S. H.; Whiteman, D. N.; Evans, K. D.; Poellot, M.; Kaufman, Y. J.

    1998-01-01

    Aerosol backscattering and extinction profiles measured by the NASA Goddard Space Flight Center Scanning Raman Lidar (SRL) during the remote cloud sensing (RCS) intensive operations period (IOP) at the Department of Energy Atmospheric Radiation Measurement (ARM) southern Great Plains (SGP) site during two nights in April 1994 are discussed. These profiles are shown to be consistent with the simultaneous aerosol size distribution measurements made by a PCASP (Passive Cavity Aerosol Spectrometer Probe) optical particle counter flown on the University of North Dakota Citation aircraft. We describe a technique which uses both lidar and PCASP measurements to derive the dependence of particle size on relative humidity, the aerosol real refractive index n, and estimate the effective single-scattering albedo Omega(sub 0). Values of n ranged between 1.4-1.5 (dry) and 1.37-1.47 (wet); Omega(sub 0) varied between 0.7 and 1.0. The single-scattering albedo derived from this technique is sensitive to the manner in which absorbing particles are represented in the aerosol mixture; representing the absorbing particles as an internal mixture rather than the external mixture assumed here results in generally higher values of Omega(sub 0). The lidar measurements indicate that the change in particle size with relative humidity as measured by the PCASP can be represented in the form discussed by Hattel with the exponent gamma = 0.3 + or - 0.05. The variations in aerosol optical and physical characteristics captured in the lidar and aircraft size distribution measurements are discussed in the context of the meteorological conditions observed during the experiment.

  14. Posttraumatic stress, effort regulation, and academic outcomes among college students: A longitudinal study.

    PubMed

    Boyraz, Güler; Granda, Rebecca; Baker, Camille N; Tidwell, Lacey Lorehn; Waits, J Brandon

    2016-07-01

    Entering college with posttraumatic stress disorder (PTSD) symptomatology has been linked to poor academic performance and increased risk for dropping out of college; however, little is known regarding the mechanisms by which PTSD symptoms have deleterious effects on college outcomes. Drawing from a self-regulated learning (SRL) perspective, which suggests that students' learning behaviors and outcomes can be influenced by contextual and developmental factors, we hypothesized that students who enter college with high PTSD symptomatology may experience difficulties in effort regulation, which in turn, may have deleterious effects on their academic performance and college persistence. These hypothesized relationships, as well as the potential gender differences in these relationships were examined using a longitudinal study design and a multigroup structural equation modeling approach. Of the 928 1st-year students who participated in the study, 484 (52.2%) students who reported lifetime exposure to traumatic events constituted the final sample of the study. The prevalence of PTSD among the trauma-exposed participants was 12.4%. After controlling for participation in on-campus activities and American College Testing (ACT) assessment scores, the relationship between PTSD symptomatology in the 1st semester of college and 2nd-year enrollment was mediated by effort regulation and 1st-year cumulative grade-point average (GPA). Specifically, participants who started college with higher levels of PTSD symptomatology also reported lower levels of effort regulation, which in turn, had a significant indirect effect on 2nd-year enrollment through 1st-year GPA. Results also indicated that the paths in the hypothesized model were not significantly different for men and women. (PsycINFO Database Record

  15. Fabrication and characterization of MCC approved testing material: ATM-9 glass

    SciTech Connect

    Wald, J.W.

    1986-06-01

    The Materials Characterization Center ATM-9 glass is designed to be representative of glass to be produced by the Defense Waste Processing Facility at the Savannah River Plant, Aiken, South Carolina. ATM-9 glass contains all of the major components of the DWPF glass and corresponds to a waste loading of 29 wt %. The feedstock material for this glass was supplied by Savannah River Laboratory, Aiken, SC, as SRL-165 Black Frit to which was added Ba, Cs, Md, Nd, Zr, as well as /sup 99/Tc, depleted U, /sup 237/Np, /sup 239 +240/Pu, and /sup 243/Am. The glass was produced under reducing conditions by the addition of 0.7 wt % graphite during the final melting process. Three kilograms of the glass were produced from April to May of 1984. On final melting, the glass was formed into stress-annealed rectangular bars of two sizes: 1.9 x 1.9 x 10 cm and 1.3 x 1.3 x 10 cm. Seventeen bars of each size were made. The analyzed composition of ATM-9 glass is listed. Examination by optical microscopy of a single transverse section from one bar showed random porosity estimated at 0.36 vol % with nominal pore diameters ranging from approx. 5 ..mu..m to 200 ..mu..m. Only one distinct second phase was observed and it was at a low concentraction level in the glass matrix. The phase appeared as spherical metallic particles. X-ray diffraction analysis of this same sample did not show any diffraction peaks from crystalline components, indicating that the glass contained less than 5 wt % of crystalline devitrification products. The even shading on the radiograph exposure indicated a generally uniform distribution of radioactivity throughout the glass matrix, with no distinct high-concentration regions.

  16. Use of an alpha lipoic, methylsulfonylmethane and bromelain dietary supplement (Opera(®)) for chemotherapy-induced peripheral neuropathy management, a prospective study.

    PubMed

    Desideri, Isacco; Francolini, Giulio; Becherini, Carlotta; Terziani, Francesca; Delli Paoli, Camilla; Olmetto, Emanuela; Loi, Mauro; Perna, Marco; Meattini, Icro; Scotti, Vieri; Greto, Daniela; Bonomo, Pierluigi; Sulprizio, Susanna; Livi, Lorenzo

    2017-03-01

    Chemotherapy-induced peripheral neuropathy (CIPN) is a major clinical problem associated with a number of cytotoxic agents. OPERA(®) (GAMFARMA srl, Milan, Italy) is a new dietary supplement where α-lipoic acid, Boswellia Serrata, methylsulfonylmethane and bromelain are combined in a single capsule. The aim of this prospective study was to determine the efficacy and safety of OPERA(®) supplementation in a series of patients affected by CIPN. We selected 25 subjects with CIPN evolving during or after chemotherapy with potentially neurotoxic agents. Patients were enrolled at the first clinical manifestation of neuropathy. CIPN was assessed at the enrollment visit and subsequently repeated every 3 weeks until 12 weeks. Primary endpoint was the evaluation of changes of measured scores after 12 weeks of therapy compared to baseline evaluation. Secondary endpoints were the evaluation of neuropathy reduction at 12 weeks after beginning of therapy with OPERA(®). Analysis of VAS data showed reduction in pain perceived by patients. According to NCI-CTC sensor and motor score, mISS scale and TNSc scale, both pain and both sensor and motor neuropathic impairment decreased after 12 weeks of treatments. Treatment with OPERA supplement was well tolerated; no increase in the toxicity profile of any of the therapeutic regimen that the patients were undergoing was reported. OPERA(®) was able to improve CIPN symptoms in a prospective series of patients treated with neurotoxic chemotherapy, with no significant toxicity or interaction. Prospective RCT in a selected patients' population is warranted to confirm its promising activity.

  17. Variation in voxel value distribution and effect of time between exposures in six CBCT units.

    PubMed

    Spin-Neto, R; Gotfredsen, E; Wenzel, A

    2014-01-01

    The aim of this study is to assess the variation in voxel value distribution in volumetric data sets obtained by six cone beam CT (CBCT) units, and the effect of time between exposures. Six CBCT units [Cranex(®) 3D (CRAN; Soredex Oy, Tuusula, Finland), Scanora(®) 3D (SCAN; Soredex Oy), NewTom™ 5G (NEWT; QR Srl, Verona, Italy), Promax(®) Dimax 3 (Planmeca Oy, Helsinki, Finland), i-CAT (Imaging Sciences International, Hatfield, PA) and 3D Accuitomo FPD80 (Morita, Kyoto, Japan)] were tested. Two volumetric data sets of a dry human skull embedded in acrylic were acquired by each CBCT unit in two sessions on separate days. Each session consisted of 20 exposures: 10 acquired with 30 min between exposures and 10 acquired immediately one after the other. CBCT data were exported as digital imaging and communications in medicine (DICOM) files and converted to text files. The text files were re-organized to contain x-, y- and z-position and grey shade for each voxel. The files were merged to contain 1 record per voxel position, including the voxel values from the 20 exposures in a session. For each voxel, subtractions were performed between Data Set 1 and the remaining 19 data sets (1 - 2, 1 - 3, etc) in a session. Means, medians, ranges and standard deviations for grey shade variation in the subtraction data sets were calculated for each unit and session. For all CBCT units, variation in voxel values was observed throughout the 20 exposures. A "fingerprint" for the grey shade variation was observed for CRAN, SCAN and NEWT. For the other units, the variation was (apparently) randomly distributed. Large discrepancies in voxel value distribution are seen in CBCT images. This variation should be considered in studies that assess minute changes in CBCT images.

  18. Space sequestration below ground in old-growth spruce-beech forests-signs for facilitation?

    PubMed

    Bolte, Andreas; Kampf, Friederike; Hilbrig, Lutz

    2013-01-01

    Scientists are currently debating the effects of mixing tree species for the complementary resource acquisition in forest ecosystems. In four unmanaged old-growth spruce-beech forests in strict nature reserves in southern Sweden and northern Germany we assessed forest structure and fine rooting profiles and traits (≤2 mm) by fine root sampling and the analysis of fine root morphology and biomass. These studies were conducted in selected tree groups with four different interspecific competition perspectives: (1) spruce as a central tree, (2) spruce as competitor, (3) beech as a central tree, and (4) beech as competitor. Mean values of life fine root attributes like biomass (FRB), length (FRL), and root area index (RAI) were significantly lower for spruce than for beech in mixed stands. Vertical profiles of fine root attributes adjusted to one unit of basal area (BA) exhibited partial root system stratification when central beech is growing with spruce competitors. In this constellation, beech was able to raise its specific root length (SRL) and therefore soil exploration efficiency in the subsoil, while increasing root biomass partitioning into deeper soil layers. According to relative values of fine root attributes (rFRA), asymmetric below-ground competition was observed favoring beech over spruce, in particular when central beech trees are admixed with spruce competitors. We conclude that beech fine rooting is facilitated in the presence of spruce by lowering competitive pressure compared to intraspecific competition whereas the competitive pressure for spruce is increased by beech admixture. Our findings underline the need of spatially differentiated approaches to assess interspecific competition below ground. Single-tree approaches and simulations of below-ground competition are required to focus rather on microsites populated by tree specimens as the basic spatial study area.

  19. Hydrogeologic Setting of A/M Area: Framework for Groundwater Transport. Book 1

    SciTech Connect

    Van Pelt, R.; Lewis, S.E.; Aadland, R.K.

    1994-03-11

    This document includes a brief summary of the regional geology within a 200--mile radius of the A/M Area, a summary of stratigraphy and hydrostratigraphic nomenclature as it applies to the A/M Area, and a summary of stratigraphy and hydrostratigraphy specific to the A/M Area. Five different stratigraphic cross sections show site-specific geology of the Tertiary section of the Upper Atlantic Coastal Plain geologic province within the A/M Area. The Cretaceous section lacks detail because the deepest wells penetrate only the uppermost part of the Upper Cretaceous sediments. Most of the wells are confined to the Tertiary section. The A/M Area is located in the northwestern corner of the Savannah River Site (SRS). The area serves as a main administrative hub for the site. Between 1958 and 1985, approximately 2,000,000 pounds of volatile organic solvents (metal degreasers, primarily trichloroethylene and tetrachloroethylene) were routed to the M Area Settling Basin. Between 1954 and 1958, effluent also was discharged to Tim`s Branch via the A014 Outfall. In the main M Area Solvent Handling/Storage Area, a significant amount of leakage occurred from drums stored during this time period. Extensive quantities of solvents were transported, via the Process Sewer Line, to the M Area Settling Basin, and leaks occurred along this line as well. A smaller source area has been identified and is centered around the Savannah River Laboratory (SRL) (now called the Savannah River Technology Center [SRTC]) Complex. All of these source areas are represented by solvent contamination in the groundwater system. (Abstract Truncated)

  20. Cr(VI) Occurrence and Geochemistry in Water From Public-Supply Wells in California

    SciTech Connect

    Izbicki, John A.; Wright, Michael T.; Seymour, Whitney A.; McCleskey, R. Blaine; Fram, Miranda S.; Belitz, Kenneth; Esser, Bradley K.

    2015-08-18

    Hexavalent chromium, Cr(VI), in 918 wells sampled throughout California between 2004 and 2012 by the Groundwater Ambient Monitoring and Assessment Program—Priority Basin Project (GAMA—PBP) ranged from less than the study reporting limit (SRL) of 1 microgram per liter (μg/L) to 32 μg/L. Statewide, Cr(VI) was reported in 31 percent of sampled wells and equaled or exceeded the recently established (2014) California Maximum Contaminant Level (MCL) for Cr(VI) of 10 μg/L in 4 percent of sampled wells. Cr(VI) data collected for regulatory purposes overestimate Cr(VI) occurrence. Ninety percent of chromium was present as Cr(VI), which was detected more frequently and at higher concentrations in alkaline (pH > 8), oxic water, and more frequently in agricultural and urban land uses compared to native land uses. Chemical, isotopic (tritium and carbon-14), and noble-gas data show high Cr(VI) in water from wells in alluvial aquifers in the southern California deserts result from long groundwater-residence times and geochemical reactions such as silicate weathering that increase pH, while oxic conditions persist. High Cr(VI) in water from wells in alluvial aquifers along the west-side of the Central Valley results from high-chromium abundance in source rock eroded to form those aquifers, and areal recharge processes (including irrigation return) that mobilize chromium from the unsaturated zone. Cr(VI) co-occurred with oxyanions having similar chemistry, including vanadium, selenium, and uranium. Cr(VI) was positively correlated with nitrate, consistent with increased concentrations in areas of agricultural land use and mobilization of chromium from the unsaturated zone by irrigation return.