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Sample records for model jedi ii

  1. Jobs and Economic Development Impacts from Small Wind: JEDI Model in the Works (Presentation)

    SciTech Connect

    Tegen, S.

    2012-06-01

    This presentation covers the National Renewable Energy Laboratory's role in economic impact analysis for wind power Jobs and Economic Development Impacts (JEDI) models, JEDI results, small wind JEDI specifics, and a request for information to complete the model.

  2. International Jobs and Economic Development Impacts (I-JEDI) Model

    SciTech Connect

    2016-09-01

    International Jobs and Economic Development Impacts (I-JEDI) is a freely available economic model that estimates gross economic impacts from wind, solar, biomass, and geothermal energy projects. Building on a similar model for the United States, I-JEDI was developed by the National Renewable Energy Laboratory under the U.S. government's Enhancing Capacity for Low Emission Development Strategies (EC-LEDS) program to support partner countries in assessing economic impacts of LEDS actions in the energy sector.

  3. JEDI: Jobs and Economic Development Impacts Model Fact Sheet

    SciTech Connect

    S. Hendrickson; S.Tegen

    2009-12-01

    The Jobs and Economic Development Impact (JEDI) models are user-friendly tools that estimate the economic impacts of constructing and operating power generation and biofuel plants at the local(usually state) level. First developed by NREL's Wind Powering America program to model wind energy jobs and impacts, JEDI has been expanded to biofuels,concentrating solar power, coal, and natural gas power plants.

  4. JEDI Marine and Hydrokinetic Model: User Reference Guide

    SciTech Connect

    Goldberg, M.; Previsic, M.

    2011-04-01

    The Jobs and Economic Development Impact Model (JEDI) for Marine and Hydrokinetics (MHK) is a user-friendly spreadsheet-based tool designed to demonstrate the economic impacts associated with developing and operating MHK power systems in the United States. The JEDI MHK User Reference Guide was developed to assist users in using and understanding the model. This guide provides information on the model's underlying methodology, as well as the sources and parameters used to develop the cost data utilized in the model. This guide also provides basic instruction on model add-in features, operation of the model, and a discussion of how the results should be interpreted.

  5. JEDI: Jobs and Economic Development Impacts Model, National Renewable Energy Laboratory (NREL) (Fact Sheet)

    SciTech Connect

    Not Available

    2009-12-01

    The Jobs and Economic Development Impact (JEDI) models are user-friendly tools that estimate the economic impacts of constructing and operating power generation and biofuel plants at the local (usually state) level. First developed by NREL's Wind Powering America program to model wind energy jobs and impacts, JEDI has been expanded to biofuels, concentrating solar power, coal, and natural gas power plants. Based on project-specific and default inputs (derived from industry norms), JEDI estimates the number of jobs and economic impacts to a local area (usually a state) that could reasonably be supported by a power generation project. For example, JEDI estimates the number of in-state construction jobs from a new wind farm. This fact sheet provides an overview of the JEDI model as it pertains to wind energy projects.

  6. JEDI: Jobs and Economic Development Impact Model; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-08-01

    The Jobs and Economic Development Impact (JEDI) models are user-friendly tools that estimate the economic impacts of constructing and operating power generation and biofuel plants at the local (usually state) level. First developed by NREL’s researchers to model wind energy jobs and impacts, JEDI has been expanded to also estimate the economic impacts of biofuels, coal, conventional hydro, concentrating solar power, geothermal, marine and hydrokinetic power, natural gas, photovoltaics, and transmission lines. This fact sheet focuses on JEDI for wind energy projects.

  7. Jobs and Economic Development Impact (JEDI) Model: Offshore Wind User Reference Guide

    SciTech Connect

    Lantz, E.; Goldberg, M.; Keyser, D.

    2013-06-01

    The Offshore Wind Jobs and Economic Development Impact (JEDI) model, developed by NREL and MRG & Associates, is a spreadsheet based input-output tool. JEDI is meant to be a user friendly and transparent tool to estimate potential economic impacts supported by the development and operation of offshore wind projects. This guide describes how to use the model as well as technical information such as methodology, limitations, and data sources.

  8. Transmission Line Jobs and Economic Development Impact (JEDI) Model User Reference Guide

    SciTech Connect

    Goldberg, M.; Keyser, D.

    2013-10-01

    The Jobs and Economic Development Impact (JEDI) models, developed through the National Renewable Energy Laboratory (NREL), are freely available, user-friendly tools that estimate the potential economic impacts of constructing and operating power generation projects for a range of conventional and renewable energy technologies. The Transmission Line JEDI model can be used to field questions about the economic impacts of transmission lines in a given state, region, or local community. This Transmission Line JEDI User Reference Guide was developed to provide basic instruction on operating the model and understanding the results. This guide also provides information on the model's underlying methodology, as well as the parameters and references used to develop the cost data contained in the model.

  9. Assessment of the Value, Impact, and Validity of the Jobs and Economic Development Impacts (JEDI) Suite of Models

    SciTech Connect

    Billman, L.; Keyser, D.

    2013-08-01

    The Jobs and Economic Development Impacts (JEDI) models, developed by the National Renewable Energy Laboratory (NREL) for the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), use input-output methodology to estimate gross (not net) jobs and economic impacts of building and operating selected types of renewable electricity generation and fuel plants. This analysis provides the DOE with an assessment of the value, impact, and validity of the JEDI suite of models. While the models produce estimates of jobs, earnings, and economic output, this analysis focuses only on jobs estimates. This validation report includes an introduction to JEDI models, an analysis of the value and impact of the JEDI models, and an analysis of the validity of job estimates generated by JEDI model through comparison to other modeled estimates and comparison to empirical, observed jobs data as reported or estimated for a commercial project, a state, or a region.

  10. Jobs and Economic Development Impact (JEDI) User Reference Guide: Fast Pyrolysis Biorefinery Model

    SciTech Connect

    Zhang, Yimin; Goldberg, Marshall

    2015-02-01

    This guide -- the JEDI Fast Pyrolysis Biorefinery Model User Reference Guide -- was developed to assist users in operating and understanding the JEDI Fast Pyrolysis Biorefinery Model. The guide provides information on the model's underlying methodology, as well as the parameters and data sources used to develop the cost data utilized in the model. This guide also provides basic instruction on model add-in features and a discussion of how the results should be interpreted. Based on project-specific inputs from the user, the JEDI Fast Pyrolysis Biorefinery Model estimates local (e.g., county- or state-level) job creation, earnings, and output from total economic activity for a given fast pyrolysis biorefinery. These estimates include the direct, indirect and induced economic impacts to the local economy associated with the construction and operation phases of biorefinery projects.Local revenue and supply chain impacts as well as induced impacts are estimated using economic multipliers derived from the IMPLAN software program. By determining the local economic impacts and job creation for a proposed biorefinery, the JEDI Fast Pyrolysis Biorefinery Model can be used to field questions about the added value biorefineries might bring to a local community.

  11. Jobs and Economic Development Impact (JEDI) Model Geothermal User Reference Guide

    SciTech Connect

    Johnson, C.; Augustine, C.; Goldberg, M.

    2012-09-01

    The Geothermal Jobs and Economic Development Impact (JEDI) model, developed through the National Renewable Energy Laboratory (NREL), is an Excel-based user-friendly tools that estimates the economic impacts of constructing and operating hydrothermal and Enhanced Geothermal System (EGS) power generation projects at the local level for a range of conventional and renewable energy technologies. The JEDI Model Geothermal User Reference Guide was developed to assist users in using and understanding the model. This guide provides information on the model's underlying methodology, as well as the parameters and references used to develop the cost data utilized in the model. This guide also provides basic instruction on model add-in features, operation of the model, and a discussion of how the results should be interpreted.

  12. Petroleum Refinery Jobs and Economic Development Impact (JEDI) Model User Reference Guide

    SciTech Connect

    Goldberg, M.

    2013-12-31

    The Jobs and Economic Development Impact (JEDI) models, developed through the National Renewable Energy Laboratory (NREL), are user-friendly tools utilized to estimate the economic impacts at the local level of constructing and operating fuel and power generation projects for a range of conventional and renewable energy technologies. The JEDI Petroleum Refinery Model User Reference Guide was developed to assist users in employing and understanding the model. This guide provides information on the model's underlying methodology, as well as the parameters and references used to develop the cost data utilized in the model. This guide also provides basic instruction on model add-in features, operation of the model, and a discussion of how the results should be interpreted. Based on project-specific inputs from the user, the model estimates job creation, earning and output (total economic activity) for a given petroleum refinery. This includes the direct, indirect and induced economic impacts to the local economy associated with the refinery's construction and operation phases. Project cost and job data used in the model are derived from the most current cost estimations available. Local direct and indirect economic impacts are estimated using economic multipliers derived from IMPLAN software. By determining the regional economic impacts and job creation for a proposed refinery, the JEDI Petroleum Refinery model can be used to field questions about the added value refineries may bring to the local community.

  13. Job and Economic Development Impact (JEDI) Model: A User-Friendly Tool to Calculate Economic Impacts from Wind Projects; Preprint

    SciTech Connect

    Sinclair, K.; Milligan, M.; Goldberg, M.

    2004-03-01

    The U.S. Department of Energy/National Renewable Energy Laboratory (DOE/NREL) has developed a spreadsheet-based wind model (Jobs and Economic Development Impact (JEDI)) that incorporates economic multipliers for jobs, income, and output. Originally developed with state-specific parameters, it can also be used to conduct county and regional analyses. NREL has enlisted the Wind Powering America (WPA) State Wind Working Groups (SWWGs) to conduct county-specific economic impact analyses and has encouraged them to use JEDI if they do not have their own economic model. The objective of the analyses is to identify counties within WPA target states, and preferably counties with a significant agricultural sector, that could economically benefit from wind development. These counties could then explore opportunities to tap into the United States Department of Agriculture (USDA) Farm Bill Section 9006 grants and loans to stimulate wind development. This paper describes the JEDI model and how i t can be used. We will also summarize a series of analyses that were completed to fulfill a General Accounting Office (GAO) request to provide estimates of the economic development benefits of wind power.

  14. Joint Exchange Development Initiative (JEDI) with the SKA Africa

    NASA Astrophysics Data System (ADS)

    Oozeer, Nadeem; Bassett, Bruce A.

    2015-01-01

    The teaching is a process whereby one mediates between another person and the materials. There exists many teaching models from lectures, discussion, questioning, to independent learning and self-teaching. The Joint Exchange Development Initiative (JEDI) is a way to maximize on the teaching methodologies. The JEDI is a concept to enhance development and education via direct transfer of skills and expertise in any specific field. It is an initiative to provide development via joint exchange among stakeholders. In this paper, we describe the various JEDI workshops carried out in the Square Kilometre Array (SKA Africa) partner countries and demonstrate how these workshops are proving to be successful.

  15. Job and Economic Development Impact (JEDI) Model: A User-Friendly Tool to Calculate Economic Impacts from Wind Projects (Brochure)

    SciTech Connect

    Not Available

    2004-03-01

    This quadfold brochure provides an overview of JEDI, a free online tool to calculate the economic impacts from wind projects. The brochure lists the features of the tool, the inputs and outputs that a user can expect, visuals of the screens, and contact information. This brochure will be distributed to state wind working groups and at major wind industry conferences to inform stakeholders of this valuable tool for calculating economic impacts from wind energy projects.

  16. JEDI -- The Jupiter Energetic Particle Detector for the Juno mission

    NASA Astrophysics Data System (ADS)

    Haggerty, D. K.; Mauk, B. H.; Paranicas, C. P.

    2008-12-01

    The Juno mission provides the first opportunity to conduct an in-depth exploration of Jupiter's polar magnetosphere. The high-inclination, low-periapsis orbit provides in-situ access to three critical regions: the auroral magnetic field lines, the equatorial magnetosphere, and the polar ionosphere. The Jupiter Energetic Particle Detector Instrument (JEDI) is one of several Juno magnetospheric instruments that will work together to resolve critical scientific questions about these novel environments, most importantly how Jupiter's dramatic aurora is generated. JEDI measures the energy, spectra, mass species (H, He, O, S), and angular distributions of the higher energy charged particles that: 1) are accelerated at low altitude by Jovian auroral processes, 2) precipitate into Jupiter's upper atmosphere, 3) heat and ionize the Jovian upper atmosphere, and 4) populate Jupiter's inner magnetosphere. JEDI is a compact, light-weight, time-of-flight (TOF) spectrometer that makes 3-parameter TOF and energy ion measurements, 2-parameter TOF-only ion measurements, and single parameter electron measurements in the 10-keV to 10-MeV ion and the 25-keV to 1-MeV electron energy range. The rapid spacecraft motion and slow spacecraft rotation requires that JEDI simultaneously and continuously resolve both magnetic loss cones at every position inside of ~3RJ. To achieve these measurements JEDI uses multiple sensors, each with six angular sectors evenly distributed in a 160° x 12° fan. Through these multiple views JEDI continuously samples within a 360° plane roughly normal to the spacecraft spin axis with full-sky coplanar coverage achieved each spacecraft spin. JEDI with its low resource requirements and rad-hard, high-speed electronics will make the demanding scientific observations required by the Juno mission.

  17. JEDI observations of energetic ions in the Jovian polar regions

    NASA Astrophysics Data System (ADS)

    Haggerty, D. K.; Mauk, B.; Paranicas, C.; Clark, G. B.; Kollmann, P.; Rymer, A. M.; Bolton, S. J.; Connerney, J. E. P.; Levin, S.

    2016-12-01

    After a successful orbit insertion, the Juno spacecraft completed its first 53.5 day orbit and entered perijove with the full scientific payload operational for the first time. The Jupiter Energetic particle Detector Instrument (JEDI) measures energetic ions and electrons with a combination of energy deposition in a set of solid state detectors (SSD) and a time-of-flight (TOF) system using thin foils and micro-channel plates. The combination of TOF and energy are combined to determine the velocity, mass, and species of the ions. The incident energy of the electrons is determined with the SSD energy measurement alone. Of the three JEDI units, one measures nearly 4 pi sr once each spin, while the other two JEDI instruments are arranged in a fan, that while over the Jovian poles, samples a plane nearly parallel with the magnetic field at a very high cadence. The JEDI instruments measure ions beginning from a few keV through approximately 20 MeV. The instruments can resolve the major ion species beginning 30 keV/n, with coarser mass resolution below that. This report focuses on the energetic ions observed over the poles and through closest approach. Of particular interest are the ions that precipitate from the magnetosphere onto the polar atmosphere, and ions that are accelerated locally by Jupiter's powerful auroral processes. We report preliminary findings on the spatial variations, species, spectra, and pitch angle distribution throughout the prime science region of the Juno mission.

  18. The adaptor protein GULP promotes Jedi-1-mediated phagocytosis through a clathrin-dependent mechanism.

    PubMed

    Sullivan, Chelsea S; Scheib, Jami L; Ma, Zhong; Dang, Rajan P; Schafer, Johanna M; Hickman, Francis E; Brodsky, Frances M; Ravichandran, Kodi S; Carter, Bruce D

    2014-06-15

    During the development of the peripheral nervous system, the large number of apoptotic neurons generated are phagocytosed by glial precursor cells. This clearance is mediated, in part, through the mammalian engulfment receptor Jedi-1. However, the mechanisms by which Jedi-1 mediates phagocytosis are poorly understood. Here we demonstrate that Jedi-1 associates with GULP, the mammalian homologue of CED-6, an adaptor protein required for phagocytosis mediated by the nematode engulfment receptor CED-1. Silencing GULP or mutating the NPXY motif in Jedi-1, which is required for GULP binding, prevents Jedi-1-mediated phagocytosis. How GULP promotes engulfment is not known. Of interest, we find that Jedi-1-induced phagocytosis requires GULP binding to clathrin heavy chain (CHC). During engulfment, CHC is tyrosine phosphorylated, which is required for Jedi-mediated engulfment. Both phosphoclathrin and actin accumulate around engulfed microspheres. Furthermore, knockdown of CHC in HeLa cells prevents Jedi-1-mediated engulfment of microspheres, and knockdown in glial precursors prevents the engulfment of apoptotic neurons. Taken together, these results reveal that Jedi-1 signals through recruitment of GULP, which promotes phagocytosis through a noncanonical phosphoclathrin-dependent mechanism. © 2014 Sullivan et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  19. von Willebrand factor, Jedi knight of the bloodstream.

    PubMed

    Springer, Timothy A

    2014-08-28

    When blood vessels are cut, the forces in the bloodstream increase and change character. The dark side of these forces causes hemorrhage and death. However, von Willebrand factor (VWF), with help from our circulatory system and platelets, harnesses the same forces to form a hemostatic plug. Force and VWF function are so closely intertwined that, like members of the Jedi Order in the movie Star Wars who learn to use "the Force" to do good, VWF may be considered the Jedi knight of the bloodstream. The long length of VWF enables responsiveness to flow. The shape of VWF is predicted to alter from irregularly coiled to extended thread-like in the transition from shear to elongational flow at sites of hemostasis and thrombosis. Elongational force propagated through the length of VWF in its thread-like shape exposes its monomers for multimeric binding to platelets and subendothelium and likely also increases affinity of the A1 domain for platelets. Specialized domains concatenate and compact VWF during biosynthesis. A2 domain unfolding by hydrodynamic force enables postsecretion regulation of VWF length. Mutations in VWF in von Willebrand disease contribute to and are illuminated by VWF biology. I attempt to integrate classic studies on the physiology of hemostatic plug formation into modern molecular understanding, and point out what remains to be learned.

  20. Jedi-1 and MEGF10 signal engulfment of apoptotic neurons through the tyrosine kinase Syk.

    PubMed

    Scheib, Jami L; Sullivan, Chelsea S; Carter, Bruce D

    2012-09-19

    During the development of the peripheral nervous system there is extensive apoptosis, and these neuronal corpses need to be cleared to prevent an inflammatory response. Recently, Jedi-1 and MEGF10, both expressed in glial precursor cells, were identified in mouse as having an essential role in this phagocytosis (Wu et al., 2009); however, the mechanisms by which they promote engulfment remained unknown. Both Jedi-1 and MEGF10 are homologous to the Drosophila melanogaster receptor Draper, which mediates engulfment through activation of the tyrosine kinase Shark. Here, we identify Syk, the mammalian homolog of Shark, as a signal transducer for both Jedi-1 and MEGF10. Syk interacted with each receptor independently through the immunoreceptor tyrosine-based activation motifs (ITAMs) in their intracellular domains. The interaction was enhanced by phosphorylation of the tyrosines in the ITAMs by Src family kinases (SFKs). Jedi association with Syk and activation of the kinase was also induced by exposure to dead cells. Expression of either Jedi-1 or MEGF10 in HeLa cells facilitated engulfment of carboxylated microspheres to a similar extent, and there was no additive effect when they were coexpressed. Mutation of the ITAM tyrosines of Jedi-1 and MEGF10 prevented engulfment. The SFK inhibitor PP2 or a selective Syk inhibitor (BAY 61-3606) also blocked engulfment. Similarly, in cocultures of glial precursors and dying sensory neurons from embryonic mice, addition of PP2 or knock down of endogenous Syk decreased the phagocytosis of apoptotic neurons. These results indicate that both Jedi-1 and MEGF10 can mediate phagocytosis independently through the recruitment of Syk.

  1. User-Friendly Tool to Calculate Economic Impacts from Coal, Natural Gas, and Wind: The Expanded Jobs and Economic Development Impact Model (JEDI II); Preprint

    SciTech Connect

    Tegen, S.; Goldberg, M.; Milligan, M.

    2006-06-01

    In this paper we examine the impacts of building new coal, gas, or wind plants in three states: Colorado, Michigan, and Virginia. Our findings indicate that local/state economic impacts are directly related to the availability and utilization of local industries and services to build and operate the power plant. For gas and coal plants, the economic benefit depends significantly on whether the fuel is obtained from within the state, out of state, or some combination. We also find that the taxes generated by power plants can have a significant impact on local economies via increased expenditures on public goods.

  2. 78 FR 25532 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel OCEAN JEDI; Invitation for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-01

    ...-7 day charters.'' Geographic Region: New York, Florida, North Carolina, South Carolina, California... Maritime Administration Requested Administrative Waiver of the Coastwise Trade Laws: Vessel OCEAN JEDI... Administration (MARAD), is authorized to grant waivers of the U.S.-build requirement of the coastwise laws...

  3. Jedi Public Health: Co-creating an Identity-Safe Culture to Promote Health Equity.

    PubMed

    Geronimus, Arline T; James, Sherman A; Destin, Mesmin; Graham, Louis A; Hatzenbuehler, Mark; Murphy, Mary; Pearson, Jay A; Omari, Amel; Thompson, James Phillip

    2016-12-01

    The extent to which socially-assigned and culturally mediated social identity affects health depends on contingencies of social identity that vary across and within populations in day-to-day life. These contingencies are structurally rooted and health damaging inasmuch as they activate physiological stress responses. They also have adverse effects on cognition and emotion, undermining self-confidence and diminishing academic performance. This impact reduces opportunities for social mobility, while ensuring those who "beat the odds" pay a physical price for their positive efforts. Recent applications of social identity theory toward closing racial, ethnic, and gender academic achievement gaps through changing features of educational settings, rather than individual students, have proved fruitful. We sought to integrate this evidence with growing social epidemiological evidence that structurally-rooted biopsychosocial processes have population health effects. We explicate an emergent framework, Jedi Public Health (JPH). JPH focuses on changing features of settings in everyday life, rather than individuals, to promote population health equity, a high priority, yet, elusive national public health objective. We call for an expansion and, in some ways, a re-orienting of efforts to eliminate population health inequity. Policies and interventions to remove and replace discrediting cues in everyday settings hold promise for disrupting the repeated physiological stress process activation that fuels population health inequities with potentially wide application.

  4. Interaction of Jovian energetic particles with moons and gas tori based on recent Juno/JEDI data

    NASA Astrophysics Data System (ADS)

    Kollmann, P.; Mauk, B.; Clark, G. B.; Paranicas, C.; Haggerty, D. K.; Rymer, A. M.; Bolton, S. J.; Connerney, J. E. P.; Levin, S.

    2016-12-01

    Juno is the first spacecraft in a polar orbit around Jupiter. It entered orbit in July 2016, will deliver the first science data from near Jupiter at the end of August, and pass very close to Jupiter 4 more times by December. We will use data from the three JEDI instruments onboard that measure ions and electrons in the tens of keV to MeV range while discriminating among ion species. Recording of the full energy and time-of-flight information of a subset of the detected particles will allow distinguishing foreground from contaminating background in many cases. Since Juno will be mostly at high latitudes, the JEDI measurements will differ from the measurements of previous missions that were mostly in the equatorial plane. The increasingly strong radiation environment inwards of Europa's orbit caused contamination and/or dead time effects in many of the previously flown particle instruments, which made it difficult to study this region with the existing data. We expect that Juno's unique orbit and the JEDI design will largely avoid these problems. During one hour of closest approach, Juno will be on magnetic field lines that map within the orbits of the Galilean moons. We will study the data in this region and analyze the intensity dropouts that are caused by the interaction between the particles that bounce along field lines and drift around the planet with the moons and associated gas and plasma tori. Also, we will analyze the rate of intensity change towards Jupiter that is determined by radial transport, potential local source processes, and the range of pitch angles that can reach the changing latitudes.

  5. Juno/JEDI observations of energetic particles near closest approach to Jupiter - Evidence for heavy ion precipitation in the Jovian auroral region

    NASA Astrophysics Data System (ADS)

    Haggerty, Dennis; Mauk, Barry; Paranicas, Chris; Clark, George; Kollmann, Peter; Rymer, Abigail; Bolton, Scott; Connerney, Jack; Levin, Steve

    2017-04-01

    The Juno spacecraft's polar orbit provides an exceptional opportunity to study auroral processes in the largest and most dynamic auroral region in the solar system. The Jupiter Energetic particle Detector Instruments (JEDI) have SSD telescopes with multiple look directions and additional time-of-flight capabilities to measure ions and electrons from 6 keV to 20 MeV. These instruments resolve major ion species beginning at 30 keV/n, with coarser mass resolution for lower energy ions. JEDI instruments observed energetic heavy ions up to 20 MeV precipitating into the auroral regions during the first few Juno perijoves that have occurred to date. The observed heavy ion intensity was lower than expected, but composition of the precipitating ions included the predicted species oxygen and sulfur. During the first perijove pass, an unexpected element was observed with an atomic mass between oxygen and sulfur with intensity comparable to the other heavy ions. Preliminary analysis of the JEDI composition data indicates magnesium, with an unexpected energy spectrum beginning around 500 keV and extending up through 20 MeV. During the third perijove pass no significant intensity of energetic magnesium was observed, which suggests that the source of this element is intermittent. We report on the new findings of energetic heavy ions from the first few Juno orbits including the auroral regions, observations through closest approach, and discuss possible source mechanisms for the unexpected and transient observation of heavy ions.

  6. Hydrodynamical models of cometary H ii regions

    NASA Astrophysics Data System (ADS)

    Steggles, H. G.; Hoare, M. G.; Pittard, J. M.

    2017-04-01

    We have modelled the evolution of cometary H ii regions produced by zero-age main-sequence stars of O and B spectral types, which are driving strong winds and are born off-centre from spherically symmetric cores with power-law (α = 2) density slopes. A model parameter grid was produced that spans stellar mass, age and core density. Exploring this parameter space, we investigated limb-brightening, a feature commonly seen in cometary H ii regions. We found that stars with mass M⋆ ≥ 12 M⊙ produce this feature. Our models have a cavity bounded by a contact discontinuity separating hot shocked wind and ionized ambient gas that is similar in size to the surrounding H ii region. Because of early pressure confinement, we did not see shocks outside of the contact discontinuity for stars with M⋆ ≤ 40 M⊙, but the cavities were found to continue to grow. The cavity size in each model plateaus as the H ii region stagnates. The spectral energy distributions of our models are similar to those from identical stars evolving in uniform density fields. The turn-over frequency is slightly lower in our power-law models as a result of a higher proportion of low-density gas covered by the H ii regions.

  7. EXODUS II: A finite element data model

    SciTech Connect

    Schoof, L.A.; Yarberry, V.R.

    1994-09-01

    EXODUS II is a model developed to store and retrieve data for finite element analyses. It is used for preprocessing (problem definition), postprocessing (results visualization), as well as code to code data transfer. An EXODUS II data file is a random access, machine independent, binary file that is written and read via C, C++, or Fortran library routines which comprise the Application Programming Interface (API).

  8. User Guide for the International Jobs and Economic Development Impacts Model

    SciTech Connect

    Keyser, David; Flores-Espino, Francisco; Uriarte, Caroline; Cox, Sadie

    2016-09-01

    The International Jobs and Economic Development Impacts (I-JEDI) model is a freely available economic model that estimates gross economic impacts from wind, solar, and geothermal energy projects for several different countries. Building on the original JEDI model, which was developed for the United States, I-JEDI was developed under the USAID Enhancing Capacity for Low Emission Development Strategies (EC-LEDS) program to support countries in assessing economic impacts of LEDS actions in the energy sector. I-JEDI estimates economic impacts by characterizing the construction and operation of energy projects in terms of expenditures and the portion of these expenditures made within the country of analysis. These data are then used in a country-specific input-output (I-O) model to estimate employment, earnings, gross domestic product (GDP), and gross output impacts. Total economic impacts are presented as well as impacts by industry. This user guide presents general information about how to use I-JEDI and interpret results as well as detailed information about methodology and model limitations.

  9. Inert doublet model and LEP II limits

    SciTech Connect

    Lundstroem, Erik; Gustafsson, Michael; Edsjoe, Joakim

    2009-02-01

    The inert doublet model is a minimal extension of the standard model introducing an additional SU(2) doublet with new scalar particles that could be produced at accelerators. While there exists no LEP II analysis dedicated for these inert scalars, the absence of a signal within searches for supersymmetric neutralinos can be used to constrain the inert doublet model. This translation however requires some care because of the different properties of the inert scalars and the neutralinos. We investigate what restrictions an existing DELPHI Collaboration study of neutralino pair production can put on the inert scalars and discuss the result in connection with dark matter. We find that although an important part of the inert doublet model parameter space can be excluded by the LEP II data, the lightest inert particle still constitutes a valid dark matter candidate.

  10. Line emission from H II blister models

    NASA Technical Reports Server (NTRS)

    Rubin, R. H.

    1984-01-01

    Numerical techniques to calculate the thermal and geometric properties of line emission from H II 'blister' regions are presented. It is assumed that the density distributions of the H II regions are a function of two dimensions, with rotational symmetry specifying the shape in three-dimensions. The thermal and ionization equilibrium equations of the problem are solved by spherical modeling, and a spherical sector approximation is used to simplify the three-dimensional treatment of diffuse ionizing radiation. The global properties of H II 'blister' regions near the edges of a molecular cloud are simulated by means of the geometry/density distribution, and the results are compared with observational data. It is shown that there is a monotonic increase of peak surface brightness from the i = 0 deg (pole-on) observational position to the i = 90 deg (edge-on) position. The enhancement of the line peak intensity from the edge-on to the pole-on positions is found to depend on the density, stratification, ionization, and electron temperature weighting. It is found that as i increases, the position of peak line brightness of the lower excitation species is displaced to the high-density side of the high excitation species.

  11. Line emission from H II blister models

    NASA Technical Reports Server (NTRS)

    Rubin, R. H.

    1984-01-01

    Numerical techniques to calculate the thermal and geometric properties of line emission from H II 'blister' regions are presented. It is assumed that the density distributions of the H II regions are a function of two dimensions, with rotational symmetry specifying the shape in three-dimensions. The thermal and ionization equilibrium equations of the problem are solved by spherical modeling, and a spherical sector approximation is used to simplify the three-dimensional treatment of diffuse ionizing radiation. The global properties of H II 'blister' regions near the edges of a molecular cloud are simulated by means of the geometry/density distribution, and the results are compared with observational data. It is shown that there is a monotonic increase of peak surface brightness from the i = 0 deg (pole-on) observational position to the i = 90 deg (edge-on) position. The enhancement of the line peak intensity from the edge-on to the pole-on positions is found to depend on the density, stratification, ionization, and electron temperature weighting. It is found that as i increases, the position of peak line brightness of the lower excitation species is displaced to the high-density side of the high excitation species.

  12. Tritium modeling/BEATRIX-II data analysis

    SciTech Connect

    Billone, M.C.; Attaya, H.; Johnson, C.E.; Kopasz, J.P.

    1992-12-31

    Models have been developed to describe the tritium transport in Li{sub 2}O. The mechanisms considered are bulk diffusion, surface desorption, surface adsorption, and solubility. These models have been incorporated into the TIARA steady-state inventory code and the DISPL2 steady-state and transient code. Preliminary validation efforts have focused on the inventory and tritium release rate data from in-reactor, purge-flow tests VOM-15H, EXOTIC-2, CRITIC-1, and MOZART. The models and validation effort are reported in detail in ANL/FPP/TM-260. Since the BEATRIX-II data were released officially in November 1991, validation efforts have been concentrated on the tritium release rate data from the {open_quotes}isothermal{close_quotes} thin-ring sample. In this report, results are presented for the comparison of predicted long-time inventory changes (in response to temperature and hydrogen purge pressure changes) to values determined from the tritium release data.

  13. Effects of Mg II and Ca II ionization on ab-initio solar chromosphere models

    NASA Technical Reports Server (NTRS)

    Rammacher, W.; Cuntz, M.

    1991-01-01

    Acoustically heated solar chromosphere models are computed considering radiation damping by (non-LTE) emission from H(-) and by Mg II and Ca II emission lines. The radiative transfer equations for the Mg II k and Ca II K emission lines are solved using the core-saturation method with complete redistribution. The Mg II k and Ca II K cooling rates are compared with the VAL model C. Several substantial improvements over the work of Ulmschneider et al. (1987) are included. It is found that the rapid temperature rises caused by the ionization of Mg II are not formed in the middle chromosphere, but occur at larger atmospheric heights. These models represent the temperature structure of the 'real' solar chromosphere much better. This result is a major precondition for the study of ab-initio models for solar flux tubes based on MHD wave propagation and also for ab-initio models for the solar transition layer.

  14. Effects of Mg II and Ca II ionization on ab-initio solar chromosphere models

    NASA Technical Reports Server (NTRS)

    Rammacher, W.; Cuntz, M.

    1991-01-01

    Acoustically heated solar chromosphere models are computed considering radiation damping by (non-LTE) emission from H(-) and by Mg II and Ca II emission lines. The radiative transfer equations for the Mg II k and Ca II K emission lines are solved using the core-saturation method with complete redistribution. The Mg II k and Ca II K cooling rates are compared with the VAL model C. Several substantial improvements over the work of Ulmschneider et al. (1987) are included. It is found that the rapid temperature rises caused by the ionization of Mg II are not formed in the middle chromosphere, but occur at larger atmospheric heights. These models represent the temperature structure of the 'real' solar chromosphere much better. This result is a major precondition for the study of ab-initio models for solar flux tubes based on MHD wave propagation and also for ab-initio models for the solar transition layer.

  15. Spectral modeling of Type II SNe

    NASA Astrophysics Data System (ADS)

    Dessart, Luc

    2015-08-01

    The red supergiant phase represents the final stage of evolution in the life of moderate mass (8-25Msun) massive stars. Hidden from view, the core changes considerably its structure, progressing through the advanced stages of nuclear burning, and eventually becomes degenerate. Upon reaching the Chandrasekhar mass, this Fe or ONeMg core collapses, leading to the formation of a proto neutron star. A type II supernova results if the shock that forms at core bounce, eventually wins over the envelope accretion and reaches the progenitor surface.The electromagnetic display of such core-collapse SNe starts with this shock breakout, and persists for months as the ejecta releases the energy deposited initially by the shock or continuously through radioactive decay. Over a timescale of weeks to months, the originally optically-thick ejecta thins out and turns nebular. SN radiation contains a wealth of information about the explosion physics (energy, explosive nucleosynthesis), the progenitor properties (structure and composition). Polarised radiation also offers signatures that can help constrain the morphology of the ejecta.In this talk, I will review the current status of type II SN spectral modelling, and emphasise that a proper solution requires a time dependent treatment of the radiative transfer problem. I will discuss the wealth of information that can be gleaned from spectra as well as light curves, from both the early times (photospheric phase) and late times (nebular phase). I will discuss the diversity of Type SNe properties and how they are related to the diversity of red supergiant stars from which they originate.SN radiation offers an alternate means of constraining the properties of red-supergiant stars. To wrap up, I will illustrate how SNe II-P can also be used as probes, for example to constrain the metallicity of their environment.

  16. JAMSTEC E-library of Deep-sea Images (J-EDI) Realizes a Virtual Journey to the Earth's Unexplored Deep Ocean

    NASA Astrophysics Data System (ADS)

    Sasaki, T.; Azuma, S.; Matsuda, S.; Nagayama, A.; Ogido, M.; Saito, H.; Hanafusa, Y.

    2016-12-01

    The Japan Agency for Marine-Earth Science and Technology (JAMSTEC) archives a large amount of deep-sea research videos and photos obtained by JAMSTEC's research submersibles and vehicles with cameras. The web site "JAMSTEC E-library of Deep-sea Images : J-EDI" (http://www.godac.jamstec.go.jp/jedi/e/) has made videos and photos available to the public via the Internet since 2011. Users can search for target videos and photos by keywords, easy-to-understand icons, and dive information at J-EDI because operating staffs classify videos and photos as to contents, e.g. living organism and geological environment, and add comments to them.Dive survey data including videos and photos are not only valiant academically but also helpful for education and outreach activities. With the aim of the improvement of visibility for broader communities, we added new functions of 3-dimensional display synchronized various dive survey data with videos in this year.New Functions Users can search for dive survey data by 3D maps with plotted dive points using the WebGL virtual map engine "Cesium". By selecting a dive point, users can watch deep-sea videos and photos and associated environmental data, e.g. water temperature, salinity, rock and biological sample photos, obtained by the dive survey. Users can browse a dive track visualized in 3D virtual spaces using the WebGL JavaScript library. By synchronizing this virtual dive track with videos, users can watch deep-sea videos recorded at a point on a dive track. Users can play an animation which a submersible-shaped polygon automatically traces a 3D virtual dive track and displays of dive survey data are synchronized with tracing a dive track. Users can directly refer to additional information of other JAMSTEC data sites such as marine biodiversity database, marine biological sample database, rock sample database, and cruise and dive information database, on each page which a 3D virtual dive track is displayed. A 3D visualization of a dive

  17. Dinuclear Zn(II) and mixed Cu(II)-Zn(II) complexes of artificial patellamides as phosphatase models.

    PubMed

    Comba, Peter; Eisenschmidt, Annika; Gahan, Lawrence R; Hanson, Graeme R; Mehrkens, Nina; Westphal, Michael

    2016-12-21

    The patellamides (cyclic pseudo-octapeptides) are produced by Prochloron, a symbiont of the ascidians, marine invertebrate filter feeders. These pseudo-octapeptides are present in the cytoplasm and a possible natural function of putative metal complexes of these compounds is hydrolase activity, however the true biological role is still unknown. The dinuclear Cu(II) complexes of synthetic patellamide derivatives have been shown in in vitro experiments to be efficient hydrolase model catalysts. Many hydrolase enzymes, specifically phosphatases and carboanhydrases, are Zn(II)-based enzymes and therefore, we have studied the Zn(II) and mixed Zn(II)/Cu(II) solution chemistry of a series of synthetic patellamide derivatives, including solution structural and computational work, with the special focus on model phosphatase chemistry with bis-(2,4-dinitrophenyl)phosphate (BDNPP) as the substrate. The Zn(II) complexes of a series of ligands are shown to form complexes of similar structure and stability compared to the well-studied Cu(II) analogues and the phosphatase reactivities are also similar. Since the complex stabilities and phosphatase activities are generally a little lower compared to those of Cu(II) and since the concentration of Zn(II) in Prochloron cells is slightly smaller, we conclude that the Cu(II) complexes of the patellamides are more likely to be of biological importance.

  18. Finite State Machines and Modal Models in Ptolemy II

    DTIC Science & Technology

    2009-11-01

    Finite State Machines and Modal Models in Ptolemy II Edward A. Lee Electrical Engineering and Computer Sciences University of California at Berkeley...DATES COVERED 00-00-2009 to 00-00-2009 4. TITLE AND SUBTITLE Finite State Machines and Modal Models in Ptolemy II 5a. CONTRACT NUMBER 5b...describes the usage and semantics of finite-state machines (FSMs) and modal models in Ptolemy II. FSMs are actors whose behavior is described using a

  19. Modeling Topaz-II system performance

    SciTech Connect

    Lee, H.H.; Klein, A.C. )

    1993-01-01

    The US acquisition of the Topaz-11 in-core thermionic space reactor test system from Russia provides a good opportunity to perform a comparison of the Russian reported data and the results from computer codes such as MCNP (Ref. 3) and TFEHX (Ref. 4). The comparison study includes both neutronic and thermionic performance analyses. The Topaz II thermionic reactor is modeled with MCNP using actual Russian dimensions and parameters. The computation of the neutronic performance considers several important aspects such as the fuel enrichment and location of the thermionic fuel elements (TFES) in the reactor core. The neutronic analysis included the calculation of both radial and axial power distribution, which are then used in the TFEHX code for electrical performance. The reactor modeled consists of 37 single-cell TFEs distributed in a 13-cm-radius zirconium hydride block surrounded by 8 cm of beryllium metal reflector. The TFEs use 90% enriched [sup 235]U and molybdenum coated with a thin layer of [sup 184]W for emitter surface. Electrons emitted are captured by a collector surface with a gap filled with cesium vapor between the collector and emitter surfaces. The collector surface is electrically insulated with alumina. Liquid NaK provides the cooling system for the TFEs. The axial thermal power distribution is obtained by dividing the TFE into 40 axial nodes. Comparison of the true axial power distribution with that produced by electrical heaters was also performed.

  20. Modeling interactions of Hg(II) and bauxitic soils.

    PubMed

    Weerasooriya, Rohan; Tobschall, Heinz J; Bandara, Atula

    2007-11-01

    The adsorptive interactions of Hg(II) with gibbsite-rich soils (hereafter SOIL-g) were modeled by 1-pK surface complexation theory using charge distribution multi-site ion competition model (CD MUSIC) incorporating basic Stern layer model (BSM) to account for electrostatic effects. The model calibrations were performed for the experimental data of synthetic gibbsite-Hg(II) adsorption. When [NaNO(3)] > or = 0.01M, the Hg(II) adsorption density values, of gibbsite, Gamma(Hg(II)), showed a negligible variation with ionic strength. However, Gamma(Hg(II)) values show a marked variation with the [Cl(-)]. When [Cl(-)] > or = 0.01M, the Gamma(Hg(II)) values showed a significant reduction with the pH. The Hg(II) adsorption behavior in NaNO(3) was modeled assuming homogeneous solid surface. The introduction of high affinity sites, i.e., >Al(s)OH at a low concentration (typically about 0.045 sites nm(-2)) is required to model Hg(II) adsorption in NaCl. According to IR spectroscopic data, the bauxitic soil (SOIL-g) is characterized by gibbsite and bayerite. These mineral phases were not treated discretely in modeling of Hg(II) and soil interactions. The CD MUSIC/BSM model combination can be used to model Hg(II) adsorption on bauxitic soil. The role of organic matter seems to play a role on Hg(II) binding when pH>8. The Hg(II) adsorption in the presence of excess Cl(-) ions required the selection of high affinity sites in modeling.

  1. Climate Model Datasets on Earth System Grid II (ESG II)

    DOE Data Explorer

    Earth System Grid (ESG) is a project that combines the power and capacity of supercomputers, sophisticated analysis servers, and datasets on the scale of petabytes. The goal is to provide a seamless distributed environment that allows scientists in many locations to work with large-scale data, perform climate change modeling and simulation,and share results in innovative ways. Though ESG is more about the computing environment than the data, still there are several catalogs of data available at the web site that can be browsed or search. Most of the datasets are restricted to registered users, but several are open to any access.

  2. PARALLEL MEASUREMENT AND MODELING OF TRANSPORT IN THE DARHT II BEAMLINE ON ETA II

    SciTech Connect

    Chambers, F W; Raymond, B A; Falabella, S; Lee, B S; Richardson, R A; Weir, J T; Davis, H A; Schultze, M E

    2005-05-31

    To successfully tune the DARHT II transport beamline requires the close coupling of a model of the beam transport and the measurement of the beam observables as the beam conditions and magnet settings are varied. For the ETA II experiment using the DARHT II beamline components this was achieved using the SUICIDE (Simple User Interface Connecting to an Integrated Data Environment) data analysis environment and the FITS (Fully Integrated Transport Simulation) model. The SUICIDE environment has direct access to the experimental beam transport data at acquisition and the FITS predictions of the transport for immediate comparison. The FITS model is coupled into the control system where it can read magnet current settings for real time modeling. We find this integrated coupling is essential for model verification and the successful development of a tuning aid for the efficient convergence on a useable tune. We show the real time comparisons of simulation and experiment and explore the successes and limitations of this close coupled approach.

  3. Modeling the Arm II core in MicroCap IV

    SciTech Connect

    Dalton, A.C.

    1996-11-01

    This paper reports on how an electrical model for the core of the Arm II machine was created and how to use this model. We wanted to get a model for the electrical characteristics of the ARM II core, in order to simulate this machine and to assist in the design of a future machine. We wanted this model to be able to simulate saturation, variable loss, and reset. Using the Hodgdon model and the circuit analysis program MicroCap IV, this was accomplished. This paper is written in such a way as to allow someone not familiar with the project to understand it.

  4. Model of the expansion of H II region RCW 82

    SciTech Connect

    Krasnobaev, K. V.; Kotova, G. Yu.; Tagirova, R. R. E-mail: gviana2005@gmail.com

    2014-05-10

    This paper aims to resolve the problem of formation of young objects observed in the RCW 82 H II region. In the framework of a classical trigger model the estimated time of fragmentation is larger than the estimated age of the H II region. Thus the young objects could not have formed during the dynamical evolution of the H II region. We propose a new model that helps resolve this problem. This model suggests that the H II region RCW 82 is embedded in a cloud of limited size that is denser than the surrounding interstellar medium. According to this model, when the ionization-shock front leaves the cloud it causes the formation of an accelerating dense gas shell. In the accelerated shell, the effects of the Rayleigh-Taylor (R-T) instability dominate and the characteristic time of the growth of perturbations with the observed magnitude of about 3 pc is 0.14 Myr, which is less than the estimated age of the H II region. The total time t {sub ∑}, which is the sum of the expansion time of the H II region to the edge of the cloud, the time of the R-T instability growth, and the free fall time, is estimated as 0.44 < t {sub ∑} < 0.78 Myr. We conclude that the young objects in the H II region RCW 82 could be formed as a result of the R-T instability with subsequent fragmentation into large-scale condensations.

  5. H II control for model helicopter in hover

    NASA Astrophysics Data System (ADS)

    Kim, Moo Seok; Kim, Joon Ki; Han, Jeong Yup; Park, Hong Bae; Kang, Soon Ju

    2005-12-01

    This paper presents mathematical model of six degree-of-freedom (6-DOF) helicopter (ERGO50) in hover, and H II feedback controller which is a powerful technique for the MIMO system as a helicopter. Mathematical model of the helicopter is multi-input multi-output (MIMO) and linearized system which accommodates aerodynamics. H II controller based on optimal control theory is used in a myriad application and plays an important role as a valuable precursor to other advanced methods for future work, when we need to improve stability of the helicopter. We design linear-quadratic-gaussian controller as H II controller. Simulation results show good performance.

  6. Simplified Risk Model Version II (SRM-II) Structure and Application

    SciTech Connect

    S. A. Eide; T. E. Wierman

    1999-08-01

    The Simplified Risk Model Version II (SRM-II) is a quantitative tool for efficiently evaluating the risk from Department of Energy waste management activities. Risks evaluated include human safety and health and environmental impact. Both accidents and normal, incident-free operation are considered. The risk models are simplifications of more detailed risk analyses, such as those found in environmental impact statements, safety analysis reports, and performance assessments. However, wherever possible, conservatisms in such models have been removed to obtain best estimate results. The SRM-II is used to support DOE complex-wide environmental management integration studies. Typically such studies involve risk predictions covering the entire waste management program, including such activities as initial storage, handling, treatment, interim storage, transportation, and final disposal.

  7. Simplified Risk Model Version II (SRM-II) Structure and Application

    SciTech Connect

    Eide, Steven Arvid; Wierman, Thomas Edward

    1999-08-01

    The Simplified Risk Model Version II (SRM-II) is a quantitative tool for efficiently evaluating the risk from Department of Energy waste management activities. Risks evaluated include human safety and health and environmental impact. Both accidents and normal, incident-free operation are considered. The risk models are simplifications of more detailed risk analyses, such as those found in environmental impact statements, safety analysis reports, and performance assessments. However, wherever possible, conservatisms in such models have been removed to obtain best estimate results. The SRM-II is used to support DOE complex-wide environmental management integration studies. Typically such activities involve risk predictions including such activities as initial storage, handling, treatment, interim storage, transportation, and final disposal.

  8. Standard solar model. II - g-modes

    NASA Technical Reports Server (NTRS)

    Guenther, D. B.; Demarque, P.; Pinsonneault, M. H.; Kim, Y.-C.

    1992-01-01

    The paper presents the g-mode oscillation for a set of modern solar models. Each solar model is based on a single modification or improvement to the physics of a reference solar model. Improvements were made to the nuclear reaction rates, the equation of state, the opacities, and the treatment of the atmosphere. The error in the predicted g-mode periods associated with the uncertainties in the model physics is predicted and the specific sensitivities of the g-mode periods and their period spacings to the different model structures are described. In addition, these models are compared to a sample of published observations. A remarkably good agreement is found between the 'best' solar model and the observations of Hill and Gu (1990).

  9. Test cell modeling and optimization for FPD-II

    SciTech Connect

    Haney, S.W.; Fenstermacher, M.E.

    1985-04-10

    The Fusion Power Demonstration, Configuration II (FPD-II), will ba a DT burning tandem mirror facility with thermal barriers, designed as the next step engineering test reactor (ETR) to follow the tandem mirror ignition test machines. Current plans call for FPD-II to be a multi-purpose device. For approximately the first half of its lifetime, it will operate as a high-Q ignition machine designed to reach or exceed engineering break-even and to demonstrate the technological feasibility of tandem mirror fusion. The second half of its operation will focus on the evaluation of candidate reactor blanket designs using a neutral beam driven test cell inserted at the midplane of the 90 m long cell. This machine called FPD-II+T, uses an insert configuration similar to that used in the MFTF-..cap alpha..+T study. The modeling and optimization of FPD-II+T are the topic of the present paper.

  10. Aqueous Solution Vessel Thermal Model Development II

    SciTech Connect

    Buechler, Cynthia Eileen

    2015-10-28

    The work presented in this report is a continuation of the work described in the May 2015 report, “Aqueous Solution Vessel Thermal Model Development”. This computational fluid dynamics (CFD) model aims to predict the temperature and bubble volume fraction in an aqueous solution of uranium. These values affect the reactivity of the fissile solution, so it is important to be able to calculate them and determine their effects on the reaction. Part A of this report describes some of the parameter comparisons performed on the CFD model using Fluent. Part B describes the coupling of the Fluent model with a Monte-Carlo N-Particle (MCNP) neutron transport model. The fuel tank geometry is the same as it was in the May 2015 report, annular with a thickness-to-height ratio of 0.16. An accelerator-driven neutron source provides the excitation for the reaction, and internal and external water cooling channels remove the heat. The model used in this work incorporates the Eulerian multiphase model with lift, wall lubrication, turbulent dispersion and turbulence interaction. The buoyancy-driven flow is modeled using the Boussinesq approximation, and the flow turbulence is determined using the k-ω Shear-Stress-Transport (SST) model. The dispersed turbulence multiphase model is employed to capture the multiphase turbulence effects.

  11. Predictive Models and Computational Toxicology (II IBAMTOX)

    EPA Science Inventory

    EPA’s ‘virtual embryo’ project is building an integrative systems biology framework for predictive models of developmental toxicity. One schema involves a knowledge-driven adverse outcome pathway (AOP) framework utilizing information from public databases, standardized ontologies...

  12. Predictive Models and Computational Toxicology (II IBAMTOX)

    EPA Science Inventory

    EPA’s ‘virtual embryo’ project is building an integrative systems biology framework for predictive models of developmental toxicity. One schema involves a knowledge-driven adverse outcome pathway (AOP) framework utilizing information from public databases, standardized ontologies...

  13. Nyala and Bushbuck II: A Harvesting Model.

    ERIC Educational Resources Information Center

    Fay, Temple H.; Greeff, Johanna C.

    1999-01-01

    Adds a cropping or harvesting term to the animal overpopulation model developed in Part I of this article. Investigates various harvesting strategies that might suggest a solution to the overpopulation problem without actually culling any animals. (ASK)

  14. Nyala and Bushbuck II: A Harvesting Model.

    ERIC Educational Resources Information Center

    Fay, Temple H.; Greeff, Johanna C.

    1999-01-01

    Adds a cropping or harvesting term to the animal overpopulation model developed in Part I of this article. Investigates various harvesting strategies that might suggest a solution to the overpopulation problem without actually culling any animals. (ASK)

  15. On The Modeling of Educational Systems: II

    ERIC Educational Resources Information Center

    Grauer, Robert T.

    1975-01-01

    A unified approach to model building is developed from the separate techniques of regression, simulation, and factorial design. The methodology is applied in the context of a suburban school district. (Author/LS)

  16. Engineer Modeling Study. Volume II. Users Manual.

    DTIC Science & Technology

    1982-09-01

    to have some experience with automated data processing (ADP) systems. Instructions are given for model operation on the Boeing Computer system. To...AM.y Vpor 62074 ATTII, ATA-TE-SI Riyadh 09038 Sharpe Army Dopot 95331 ATm: ATZA-PE ok I..0d 61201 s.... Ar y opot 14541 Am: Bear. Libary

  17. Implementing the Ecosystem Model: Phase II.

    ERIC Educational Resources Information Center

    Schuh, John H.

    1978-01-01

    The ecosystem model was used to assess student perceptions of certain aspects of residential life at a large university. Over 70 percent of questionnaires were returned. From the data, aspects of the environment were changed according to student recommendations. A great need for more information communication was found. (RPG)

  18. Argonne Bubble Experiment Thermal Model Development II

    SciTech Connect

    Buechler, Cynthia Eileen

    2016-07-01

    This report describes the continuation of the work reported in “Argonne Bubble Experiment Thermal Model Development”. The experiment was performed at Argonne National Laboratory (ANL) in 2014. A rastered 35 MeV electron beam deposited power in a solution of uranyl sulfate, generating heat and radiolytic gas bubbles. Irradiations were performed at three beam power levels, 6, 12 and 15 kW. Solution temperatures were measured by thermocouples, and gas bubble behavior was observed. This report will describe the Computational Fluid Dynamics (CFD) model that was developed to calculate the temperatures and gas volume fractions in the solution vessel during the irradiations. The previous report described an initial analysis performed on a geometry that had not been updated to reflect the as-built solution vessel. Here, the as-built geometry is used. Monte-Carlo N-Particle (MCNP) calculations were performed on the updated geometry, and these results were used to define the power deposition profile for the CFD analyses, which were performed using Fluent, Ver. 16.2. CFD analyses were performed for the 12 and 15 kW irradiations, and further improvements to the model were incorporated, including the consideration of power deposition in nearby vessel components, gas mixture composition, and bubble size distribution. The temperature results of the CFD calculations are compared to experimental measurements.

  19. Oxygen and seizure dynamics: II. Computational modeling

    PubMed Central

    Wei, Yina; Ullah, Ghanim; Ingram, Justin

    2014-01-01

    Electrophysiological recordings show intense neuronal firing during epileptic seizures leading to enhanced energy consumption. However, the relationship between oxygen metabolism and seizure patterns has not been well studied. Recent studies have developed fast and quantitative techniques to measure oxygen microdomain concentration during seizure events. In this article, we develop a biophysical model that accounts for these experimental observations. The model is an extension of the Hodgkin-Huxley formalism and includes the neuronal microenvironment dynamics of sodium, potassium, and oxygen concentrations. Our model accounts for metabolic energy consumption during and following seizure events. We can further account for the experimental observation that hypoxia can induce seizures, with seizures occurring only within a narrow range of tissue oxygen pressure. We also reproduce the interplay between excitatory and inhibitory neurons seen in experiments, accounting for the different oxygen levels observed during seizures in excitatory vs. inhibitory cell layers. Our findings offer a more comprehensive understanding of the complex interrelationship among seizures, ion dynamics, and energy metabolism. PMID:24671540

  20. Variables Affecting Economic Development of Wind Energy

    SciTech Connect

    Lantz, E.; Tegen, S.

    2008-07-01

    NREL's JEDI Wind model performed an analysis of wind-power-related economic development drivers. Economic development benefits for wind and coal were estimated using NREL's JEDI Wind and JEDI Coal models.

  1. PEP-II vacuum system pressure profile modeling using EXCEL

    SciTech Connect

    Nordby, M.; Perkins, C.

    1994-06-01

    A generic, adaptable Microsoft EXCEL program to simulate molecular flow in beam line vacuum systems is introduced. Modeling using finite-element approximation of the governing differential equation is discussed, as well as error estimation and program capabilities. The ease of use and flexibility of the spreadsheet-based program is demonstrated. PEP-II vacuum system models are reviewed and compared with analytical models.

  2. Mortality Probability Model III and Simplified Acute Physiology Score II

    PubMed Central

    Vasilevskis, Eduard E.; Kuzniewicz, Michael W.; Cason, Brian A.; Lane, Rondall K.; Dean, Mitzi L.; Clay, Ted; Rennie, Deborah J.; Vittinghoff, Eric; Dudley, R. Adams

    2009-01-01

    Background: To develop and compare ICU length-of-stay (LOS) risk-adjustment models using three commonly used mortality or LOS prediction models. Methods: Between 2001 and 2004, we performed a retrospective, observational study of 11,295 ICU patients from 35 hospitals in the California Intensive Care Outcomes Project. We compared the accuracy of the following three LOS models: a recalibrated acute physiology and chronic health evaluation (APACHE) IV-LOS model; and models developed using risk factors in the mortality probability model III at zero hours (MPM0) and the simplified acute physiology score (SAPS) II mortality prediction model. We evaluated models by calculating the following: (1) grouped coefficients of determination; (2) differences between observed and predicted LOS across subgroups; and (3) intraclass correlations of observed/expected LOS ratios between models. Results: The grouped coefficients of determination were APACHE IV with coefficients recalibrated to the LOS values of the study cohort (APACHE IVrecal) [R2 = 0.422], mortality probability model III at zero hours (MPM0 III) [R2 = 0.279], and simplified acute physiology score (SAPS II) [R2 = 0.008]. For each decile of predicted ICU LOS, the mean predicted LOS vs the observed LOS was significantly different (p ≤ 0.05) for three, two, and six deciles using APACHE IVrecal, MPM0 III, and SAPS II, respectively. Plots of the predicted vs the observed LOS ratios of the hospitals revealed a threefold variation in LOS among hospitals with high model correlations. Conclusions: APACHE IV and MPM0 III were more accurate than SAPS II for the prediction of ICU LOS. APACHE IV is the most accurate and best calibrated model. Although it is less accurate, MPM0 III may be a reasonable option if the data collection burden or the treatment effect bias is a consideration. PMID:19363210

  3. Models of ring galaxies. II - Extended starbursts

    NASA Technical Reports Server (NTRS)

    Struck-Marcell, Curtis; Appleton, P. N.

    1987-01-01

    Numerical models of the development of star-formation bursts in collisional ring galaxies are presented. To extend the work of Appleton and Struck-Marcell (1987) target disks which have relatively high mean cloud mass and gas density are emphasized. In such cases, even relatively low mass intruder galaxies are capable of triggering intense star-formation bursts in the density waves. Although the bursts are very short-lived in any individual gas element, pressure effects stimulate neighboring gas elements to burst, which can result in a sustained enhancement in the net star-formation rate. The results are capable of explaining the high far-infrared fluxes observed in righ galaxies and provide clues to the development of starburst activity in other colliding galaxies.

  4. Multiwell experiment: reservoir modeling analysis, Volume II

    SciTech Connect

    Horton, A.I.

    1985-05-01

    This report updates an ongoing analysis by reservoir modelers at the Morgantown Energy Technology Center (METC) of well test data from the Department of Energy's Multiwell Experiment (MWX). Results of previous efforts were presented in a recent METC Technical Note (Horton 1985). Results included in this report pertain to the poststimulation well tests of Zones 3 and 4 of the Paludal Sandstone Interval and the prestimulation well tests of the Red and Yellow Zones of the Coastal Sandstone Interval. The following results were obtained by using a reservoir model and history matching procedures: (1) Post-minifracture analysis indicated that the minifracture stimulation of the Paludal Interval did not produce an induced fracture, and extreme formation damage did occur, since a 65% permeability reduction around the wellbore was estimated. The design for this minifracture was from 200 to 300 feet on each side of the wellbore; (2) Post full-scale stimulation analysis for the Paludal Interval also showed that extreme formation damage occurred during the stimulation as indicated by a 75% permeability reduction 20 feet on each side of the induced fracture. Also, an induced fracture half-length of 100 feet was determined to have occurred, as compared to a designed fracture half-length of 500 to 600 feet; and (3) Analysis of prestimulation well test data from the Coastal Interval agreed with previous well-to-well interference tests that showed extreme permeability anisotropy was not a factor for this zone. This lack of permeability anisotropy was also verified by a nitrogen injection test performed on the Coastal Red and Yellow Zones. 8 refs., 7 figs., 2 tabs.

  5. Modeling tools for design of type-II superlattice photodetectors

    NASA Astrophysics Data System (ADS)

    Asplund, Carl; Marcks von Würtemberg, Rickard; Höglund, Linda

    2017-08-01

    In this paper, we present a range of modeling tools that are used in the design and performance evaluation of type-II superlattice detectors. Among these is an optical and photo carrier transport model for the spectral total external QE, which takes into account carrier diffusion length. Using this model, the diffusion length is extracted from external quantum efficiency measurements. It can also be used to fine-tune an optical cavity in relation to the wavelength range of interest for optimal quantum efficiency. Furthermore, an electrical device model for band bending, dark current and doping optimization is described. The modeling tools are discussed and examples of their use are given for MWIR type-II detectors based on InAs/AlSb/GaSb superlattices.

  6. Economic Development Impacts of Wind Power: A Comparative Analysis of Impacts within the Western Governors' Association States; Preprint

    SciTech Connect

    Tegen, S.; Milligan, M.; Goldberg, M.

    2007-06-01

    This paper uses NREL's newest Jobs and Economic Development Impacts (JEDI II) model to assess economic impacts from alternative power technologies, with a focus on wind energy, for a variety of states.

  7. Competitive sorption of Pb(II), Cu(II) and Ni(II) on carbonaceous nanofibers: A spectroscopic and modeling approach.

    PubMed

    Ding, Congcong; Cheng, Wencai; Wang, Xiangxue; Wu, Zhen-Yu; Sun, Yubing; Chen, Changlun; Wang, Xiangke; Yu, Shu-Hong

    2016-08-05

    The competitive sorption of Pb(II), Cu(II) and Ni(II) on the uniform carbonaceous nanofibers (CNFs) was investigated in binary/ternary-metal systems. The pH-dependent sorption of Pb(II), Cu(II) and Ni(II) on CNFs was independent of ionic strength, indicating that inner-sphere surface complexation dominated sorption Pb(II), Cu(II) and Ni(II) on CNFs. The maximum sorption capacities of Pb(II), Cu(II) and Ni(II) on CNFs in single-metal systems at a pH 5.5±0.2 and 25±1°C were 3.84 (795.65mg/g), 3.21 (204.00mg/g) and 2.67 (156.70mg/g)mmol/g, respectively. In equimolar binary/ternary-metal systems, Pb(II) exhibited greater inhibition of the sorption of Cu(II) and Ni(II), demonstrating the stronger affinity of CNFs for Pb(II). The competitive sorption of heavy metals in ternary-metal systems was predicted quite well by surface complexation modeling derived from single-metal data. According to FTIR, XPS and EXAFS analyses, Pb(II), Cu(II) and Ni(II) were specifically adsorbed on CNFs via covalent bonding. These observations should provide an essential start in simultaneous removal of multiple heavy metals from aquatic environments by CNFs, and open the doorways for the application of CNFs.

  8. THE HYDRODYNAMICAL MODELS OF THE COMETARY COMPACT H ii REGION

    SciTech Connect

    Zhu, Feng-Yao; Zhu, Qing-Feng; Li, Juan; Wang, Jun-Zhi; Zhang, Jiang-Shui E-mail: zhuqf@ustc.edu.cn E-mail: jzwang@shao.ac.cn

    2015-10-10

    We have developed a full numerical method to study the gas dynamics of cometary ultracompact H ii regions, and associated photodissociation regions (PDRs). The bow-shock and champagne-flow models with a 40.9/21.9 M{sub ⊙} star are simulated. In the bow-shock models, the massive star is assumed to move through dense (n = 8000 cm{sup −3}) molecular material with a stellar velocity of 15 km s{sup −1}. In the champagne-flow models, an exponential distribution of density with a scale height of 0.2 pc is assumed. The profiles of the [Ne ii] 12.81 μm and H{sub 2} S(2) lines from the ionized regions and PDRs are compared for two sets of models. In champagne-flow models, emission lines from the ionized gas clearly show the effect of acceleration along the direction toward the tail due to the density gradient. The kinematics of the molecular gas inside the dense shell are mainly due to the expansion of the H ii region. However, in bow-shock models the ionized gas mainly moves in the same direction as the stellar motion. The kinematics of the molecular gas inside the dense shell simply reflects the motion of the dense shell with respect to the star. These differences can be used to distinguish two sets of models.

  9. Predictive data modeling of human type II diabetes related statistics

    NASA Astrophysics Data System (ADS)

    Jaenisch, Kristina L.; Jaenisch, Holger M.; Handley, James W.; Albritton, Nathaniel G.

    2009-04-01

    During the course of routine Type II treatment of one of the authors, it was decided to derive predictive analytical Data Models of the daily sampled vital statistics: namely weight, blood pressure, and blood sugar, to determine if the covariance among the observed variables could yield a descriptive equation based model, or better still, a predictive analytical model that could forecast the expected future trend of the variables and possibly eliminate the number of finger stickings required to montior blood sugar levels. The personal history and analysis with resulting models are presented.

  10. SDSS-II: Determination of shape and color parameter coefficients for SALT-II fit model

    SciTech Connect

    Dojcsak, L.; Marriner, J.; /Fermilab

    2010-08-01

    In this study we look at the SALT-II model of Type IA supernova analysis, which determines the distance moduli based on the known absolute standard candle magnitude of the Type IA supernovae. We take a look at the determination of the shape and color parameter coefficients, {alpha} and {beta} respectively, in the SALT-II model with the intrinsic error that is determined from the data. Using the SNANA software package provided for the analysis of Type IA supernovae, we use a standard Monte Carlo simulation to generate data with known parameters to use as a tool for analyzing the trends in the model based on certain assumptions about the intrinsic error. In order to find the best standard candle model, we try to minimize the residuals on the Hubble diagram by calculating the correct shape and color parameter coefficients. We can estimate the magnitude of the intrinsic errors required to obtain results with {chi}{sup 2}/degree of freedom = 1. We can use the simulation to estimate the amount of color smearing as indicated by the data for our model. We find that the color smearing model works as a general estimate of the color smearing, and that we are able to use the RMS distribution in the variables as one method of estimating the correct intrinsic errors needed by the data to obtain the correct results for {alpha} and {beta}. We then apply the resultant intrinsic error matrix to the real data and show our results.

  11. Adhesion ability of angiotensin II with model membranes.

    PubMed

    Preu, Julia; Tiefenauer, Louis; Gutberlet, Thomas

    2017-02-01

    The octa-peptide angiotensin II (Ang II, (H2NAspArgValTyrIleHisProPheCOOH)) is one of the key player on blood pressure regulation in mammals. Predominantly binding to the Angiotensin type 1 and 2 receptors, the hormone is one of several peptide ligands binding to G protein coupled receptors (GPCR). The active hormone derives from a high molecular weight precursor sequentially cleaved by the proteases renin and the angiotensin converting enzyme (ACE). The chemical nature of the amino acid sequence has an impact on the behavior in the proximity of membranes, demonstrated using different membrane model systems and biophysical methods. Applying electrochemical impedance spectroscopy and small angle X-ray scattering a detailed view on the adhesion of the peptide with model membrane surfaces was performed. The role of specific amino acids involved in the interaction with the phospholipid head group were investigated and, studying a truncated version of Ang II, Ang (1-7), the key role of the C-terminal phenylalanine was proven. Truncation of the C-terminal amino acid abolishes the binding of the peptide to the membrane surface. A shift in pH, altering the protonation state of the central histidine residue impairs the adhesion of Ang II.

  12. Reservoir modeling of the Phase II Hot Dry Rock System

    SciTech Connect

    Zyvoloski, G.

    1984-01-01

    The Phase II system has been created with a series of hydraulic fracturing experiments at the Fenton Hill Hot Dry Rock site. Experiment 2032, the largest of the fracturing operations, involved injecting 5.6 million gallons (21,200m/sup 3/) of water into wellbore EE-2 over the period December 6-9, 1983. The experiment has been modeled using geothermal simulator FEHM developed at Los Alamos National Laboratory. The modeling effort has produced strong evidence of a large highly fractured reservoir. Two long term heat extraction schemes for the reservoir are studied with the model.

  13. Theoretical models for Type I and Type II supernova

    SciTech Connect

    Woosley, S.E.; Weaver, T.A.

    1985-01-01

    Recent theoretical progress in understanding the origin and nature of Type I and Type II supernovae is discussed. New Type II presupernova models characterized by a variety of iron core masses at the time of collapse are presented and the sensitivity to the reaction rate /sup 12/C(..cap alpha..,..gamma..)/sup 16/O explained. Stars heavier than about 20 M/sub solar/ must explode by a ''delayed'' mechanism not directly related to the hydrodynamical core bounce and a subset is likely to leave black hole remnants. The isotopic nucleosynthesis expected from these massive stellar explosions is in striking agreement with the sun. Type I supernovae result when an accreting white dwarf undergoes a thermonuclear explosion. The critical role of the velocity of the deflagration front in determining the light curve, spectrum, and, especially, isotopic nucleosynthesis in these models is explored. 76 refs., 8 figs.

  14. Comprehensive Modeling of the Apache with CAMRAD II

    NASA Technical Reports Server (NTRS)

    Jones, Henry E.; Kunz, Donald L.

    2001-01-01

    This paper presents a report of a multi year study of the U.S. Army LONGBOW APACHE (AH-64D) aircraft. The goals of this study were to provide the Apache Project Managers Office (PMO) with a broad spectrum of calibrated comprehensive and CFD models of the AH-64D aircraft. The goal of this paper is to present an overview of the comprehensive model which has been developed. The CAMRAD II computer code was chosen to complete this task. The paper first discusses issues that must be addressed when modeling the Apache using CAMRAD. The work required the acquisition of a data base for the aircraft and the development and application of a multidisciplinary computer model. Sample results from various parts of the model are presented. Conclusions with regard to the strengths and weaknesses of simulations based on this model are discussed.

  15. Comprehensive Modeling of the Apache With CAMRAD II

    NASA Technical Reports Server (NTRS)

    Jones, Henry E.; Kunz, Donald L.

    2001-01-01

    This paper presents a report of a multi year study of the U.S. Army LONGBOW APACHE (AH-64D) aircraft. The goals of this study were to provide the Apache Project Managers Office (PMO) with a broad spectrum of calibrated comprehensive and CFD models of the AH-64D aircraft. The goal of this paper is to present an overview of the comprehensive model which has been developed. The CAMRAD II computer code was chosen to complete this task. The paper first discusses issues that must be addressed when modeling the Apache using CAMRAD. The work required the acquisition of a data base for the aircraft and the development and application of a multidisciplinary computer model. Sample results from various parts of the model are presented. Conclusions with regard to the strengths and weaknesses of simulations based on this model are discussed.

  16. Comprehensive Modeling of the Apache with CAMRAD II

    NASA Technical Reports Server (NTRS)

    Jones, Henry E.; Kunz, Donald L.

    2001-01-01

    This paper presents a report of a multi year study of the U.S. Army LONGBOW APACHE (AH-64D) aircraft. The goals of this study were to provide the Apache Project Managers Office (PMO) with a broad spectrum of calibrated comprehensive and CFD models of the AH-64D aircraft. The goal of this paper is to present an overview of the comprehensive model which has been developed. The CAMRAD II computer code was chosen to complete this task. The paper first discusses issues that must be addressed when modeling the Apache using CAMRAD. The work required the acquisition of a data base for the aircraft and the development and application of a multidisciplinary computer model. Sample results from various parts of the model are presented. Conclusions with regard to the strengths and weaknesses of simulations based on this model are discussed.

  17. Comprehensive Modeling of the Apache With CAMRAD II

    NASA Technical Reports Server (NTRS)

    Jones, Henry E.; Kunz, Donald L.

    2001-01-01

    This paper presents a report of a multi year study of the U.S. Army LONGBOW APACHE (AH-64D) aircraft. The goals of this study were to provide the Apache Project Managers Office (PMO) with a broad spectrum of calibrated comprehensive and CFD models of the AH-64D aircraft. The goal of this paper is to present an overview of the comprehensive model which has been developed. The CAMRAD II computer code was chosen to complete this task. The paper first discusses issues that must be addressed when modeling the Apache using CAMRAD. The work required the acquisition of a data base for the aircraft and the development and application of a multidisciplinary computer model. Sample results from various parts of the model are presented. Conclusions with regard to the strengths and weaknesses of simulations based on this model are discussed.

  18. Simplified modeling of the EBR-II control rods

    SciTech Connect

    Angelo, P.L.

    1995-06-25

    Simplified models of EBR-II control and safety rods have been developed for core modeling under various operational and shutdown conditions. A parametric study was performed on normal worth, high worth, and safety rod type control rods. A summary of worth changes due to individual modeling approximations is tabulated. Worth effects due to structural modeling simplification are negligible. Fuel region homogenization and burnup compression contributes more than any other factor. Reference case C/E values (ratio of calculated worth from detailed model to measured worth) of 1.072 and 1.142 for safety and normal worth rods indicate acceptable errors when the approximations are used. Fuel burnup effect illustrates rod worth sensitivity to the modeling approximation. Aggregate effects are calculated under a reduced mesh.

  19. Model selection as a science driver for dark energy surveys

    NASA Astrophysics Data System (ADS)

    Mukherjee, Pia; Parkinson, David; Corasaniti, Pier Stefano; Liddle, Andrew R.; Kunz, Martin

    2006-07-01

    A key science goal of upcoming dark energy surveys is to seek time-evolution of the dark energy. This problem is one of model selection, where the aim is to differentiate between cosmological models with different numbers of parameters. However, the power of these surveys is traditionally assessed by estimating their ability to constrain parameters, which is a different statistical problem. In this paper, we use Bayesian model selection techniques, specifically forecasting of the Bayes factors, to compare the abilities of different proposed surveys in discovering dark energy evolution. We consider six experiments - supernova luminosity measurements by the Supernova Legacy Survey, SNAP, JEDI and ALPACA, and baryon acoustic oscillation measurements by WFMOS and JEDI - and use Bayes factor plots to compare their statistical constraining power. The concept of Bayes factor forecasting has much broader applicability than dark energy surveys.

  20. Atomic Data and Spectral Model for Fe II

    NASA Astrophysics Data System (ADS)

    Bautista, Manuel A.; Fivet, Vanessa; Ballance, Connor; Quinet, Pascal; Ferland, Gary; Mendoza, Claudio; Kallman, Timothy R.

    2015-08-01

    We present extensive calculations of radiative transition rates and electron impact collision strengths for Fe ii. The data sets involve 52 levels from the 3d7, 3d64s, and 3{d}54{s}2 configurations. Computations of A-values are carried out with a combination of state-of-the-art multiconfiguration approaches, namely the relativistic Hartree-Fock, Thomas-Fermi-Dirac potential, and Dirac-Fock methods, while the R-matrix plus intermediate coupling frame transformation, Breit-Pauli R-matrix, and Dirac R-matrix packages are used to obtain collision strengths. We examine the advantages and shortcomings of each of these methods, and estimate rate uncertainties from the resulting data dispersion. We proceed to construct excitation balance spectral models, and compare the predictions from each data set with observed spectra from various astronomical objects. We are thus able to establish benchmarks in the spectral modeling of [Fe ii] emission in the IR and optical regions as well as in the UV Fe ii absorption spectra. Finally, we provide diagnostic line ratios and line emissivities for emission spectroscopy as well as column densities for absorption spectroscopy. All atomic data and models are available online and through the AtomPy atomic data curation environment.

  1. Storm Water Management Model Reference Manual Volume II ...

    EPA Pesticide Factsheets

    SWMM is a dynamic rainfall-runoff simulation model used for single event or long-term (continuous) simulation of runoff quantity and quality from primarily urban areas. The runoff component of SWMM operates on a collection of subcatchment areas that receive precipitation and generate runoff and pollutant loads. The routing portion of SWMM transports this runoff through a system of pipes, channels, storage/treatment devices, pumps, and regulators. SWMM tracks the quantity and quality of runoff generated within each subcatchment, and the flow rate, flow depth, and quality of water in each pipe and channel during a simulation period comprised of multiple time steps. The reference manual for this edition of SWMM is comprised of three volumes. Volume I describes SWMM’s hydrologic models, Volume II its hydraulic models, and Volume III its water quality and low impact development models. This document provides the underlying mathematics for the hydraulic calculations of the Storm Water Management Model (SWMM)

  2. Gas dynamics modeling of the HYLIFE-II reactor

    SciTech Connect

    Jantzen, C.

    1995-08-01

    Gas dynamics in the IFE reactor, HYLIFE-II is modeled using the code, TSUNAMI. This code is a 2-D shock-solver that uses the Godunov method with operator splitting. Results from a cylindrically symmetric simulation indicate an initial, low density, burst of high energy particles enters the final focus transport lens within 40 microseconds after the blast, much faster than the proposed 1 millisecond shutter closing time. After approximately 100 microseconds the chamber debris flux levels off to one eighth its peak value and maintains this intensity until the shutter closes. Although initial protective jet ablation is considered, neither secondary radiation nor condensation are modeled. Therefore results are conservative.

  3. An integrated model of the TOPAZ-II electromagnetic pump

    SciTech Connect

    El-Genk, M.S.; Paramonov, D.V. . Inst. of Space Nuclear Power Studies)

    1994-11-01

    A detailed model of the electromagnetic pump of the TOPAZ-II space nuclear reactor power system is developed and compared with experimental data. The magnetic field strength in the pump depends not only on the current supplied by the pump thermionic fuel elements in the reactor core but also on the temperature of the coolant, the magnetic coil, and the pump structure. All electric and thermal properties of the coolant, wall material of the pump ducts, and electric leads are taken to be temperature dependent. The model predictions are in good agreement with experimental data.

  4. Dynamical modeling of elliptical galaxies. II. numerical prolate models

    SciTech Connect

    Lake, G.

    1981-01-01

    The analytical solutions of Paper I are generalized using the self-consistent field method. These prolate models are constructed using only two integrals of motion, the energy (E) and the angular momentum about the axis of symmetry, (L/sub z/). They are the first models with flattening greater than E4 which possess elliptical isophotes and realistic density profiles. The singularity in the surface brightness which characterized the models of Paper I has been removed by smoothing the extreme suppression of L/sub z/. The new models (like those of Paper I) still show a sharp rise in the velocity dispersion at the center. This feature is due to the strongly anisotropic velocity dispersions, rather than the existence of a supermassive object.

  5. Photon number conserving models of H II bubbles during reionization

    NASA Astrophysics Data System (ADS)

    Paranjape, Aseem; Choudhury, T. Roy; Padmanabhan, Hamsa

    2016-08-01

    Traditional excursion-set-based models of H II bubble growth during the epoch of reionization are known to violate photon number conservation, in the sense that the mass fraction in ionized bubbles in these models does not equal the ratio of the number of ionizing photons produced by sources and the number of hydrogen atoms in the intergalactic medium. E.g. for a Planck13 cosmology with electron scattering optical depth τ ≃ 0.066, the discrepancy is ˜15 per cent for x_{H II}=0.1 and ˜5 per cent for x_{H II}=0.5. We demonstrate that this problem arises from a fundamental conceptual shortcoming of the excursion-set approach (already recognized in the literature on this formalism) which only tracks average mass fractions instead of the exact, stochastic source counts. With this insight, we build an approximately photon number conserving Monte Carlo model of bubble growth based on partitioning regions of dark matter into haloes. Our model, which is formally valid for white noise initial conditions (ICs), shows dramatic improvements in photon number conservation, as well as substantial differences in the bubble size distribution, as compared to traditional models. We explore the trends obtained on applying our algorithm to more realistic ICs, finding that these improvements are robust to changes in the ICs. Since currently popular seminumerical schemes of bubble growth also violate photon number conservation, we argue that it will be worthwhile to pursue new, explicitly photon number conserving approaches. Along the way, we clarify some misconceptions regarding this problem that have appeared in the literature.

  6. A MODEL STUDY OF TRANSVERSE MODE COUPLING INSTABILITY AT NATIONAL SYNCHROTRON LIGHT SOURCE-II (NSLS-II).

    SciTech Connect

    BLEDNYKH, A.; WANG, J.M.

    2005-05-15

    The vertical impedances of the preliminary designs of National Synchrotron Light Source II (NSLS-II) Mini Gap Undulators (MGU) are calculated by means of GdfidL code. The Transverse Mode Coupling Instability (TMCI) thresholds corresponding to these impedances are estimated using an analytically solvable model.

  7. Verifying Ptolemy II Discrete-Event Models Using Real-Time Maude

    NASA Astrophysics Data System (ADS)

    Bae, Kyungmin; Ölveczky, Peter Csaba; Feng, Thomas Huining; Tripakis, Stavros

    This paper shows how Ptolemy II discrete-event (DE) models can be formally analyzed using Real-Time Maude. We formalize in Real-Time Maude the semantics of a subset of hierarchical Ptolemy II DE models, and explain how the code generation infrastructure of Ptolemy II has been used to automatically synthesize a Real-Time Maude verification model from a Ptolemy II design model. This enables a model-engineering process that combines the convenience of Ptolemy II DE modeling and simulation with formal verification in Real-Time Maude.

  8. Kinetic modelling for zinc (II) ions biosorption onto Luffa cylindrica

    NASA Astrophysics Data System (ADS)

    Oboh, I.; Aluyor, E.; Audu, T.

    2015-03-01

    The biosorption of Zinc (II) ions onto a biomaterial - Luffa cylindrica has been studied. This biomaterial was characterized by elemental analysis, surface area, pore size distribution, scanning electron microscopy, and the biomaterial before and after sorption, was characterized by Fourier Transform Infra Red (FTIR) spectrometer. The kinetic nonlinear models fitted were Pseudo-first order, Pseudo-second order and Intra-particle diffusion. A comparison of non-linear regression method in selecting the kinetic model was made. Four error functions, namely coefficient of determination (R2), hybrid fractional error function (HYBRID), average relative error (ARE), and sum of the errors squared (ERRSQ), were used to predict the parameters of the kinetic models. The strength of this study is that a biomaterial with wide distribution particularly in the tropical world and which occurs as waste material could be put into effective utilization as a biosorbent to address a crucial environmental problem.

  9. Kinetic modelling for zinc (II) ions biosorption onto Luffa cylindrica

    SciTech Connect

    Oboh, I.; Aluyor, E.; Audu, T.

    2015-03-30

    The biosorption of Zinc (II) ions onto a biomaterial - Luffa cylindrica has been studied. This biomaterial was characterized by elemental analysis, surface area, pore size distribution, scanning electron microscopy, and the biomaterial before and after sorption, was characterized by Fourier Transform Infra Red (FTIR) spectrometer. The kinetic nonlinear models fitted were Pseudo-first order, Pseudo-second order and Intra-particle diffusion. A comparison of non-linear regression method in selecting the kinetic model was made. Four error functions, namely coefficient of determination (R{sup 2}), hybrid fractional error function (HYBRID), average relative error (ARE), and sum of the errors squared (ERRSQ), were used to predict the parameters of the kinetic models. The strength of this study is that a biomaterial with wide distribution particularly in the tropical world and which occurs as waste material could be put into effective utilization as a biosorbent to address a crucial environmental problem.

  10. Model light curves of linear Type II supernovae

    SciTech Connect

    Swartz, D.A.; Wheeler, J.C.; Harkness, R.P. )

    1991-06-01

    Light curves computed from hydrodynamic models of supernova are compared graphically with the average observed B and V-band light curves of linear Type II supernovae. Models are based on the following explosion scenarios: carbon deflagration within a C + O core near the Chandrasekhar mass, electron-capture-induced core collapse of an O-Ne-Mg core of the Chandrasekhar mass, and collapse of an Fe core in a massive star. A range of envelope mass, initial radius, and composition is investigated. Only a narrow range of values of these parameters are consistent with observations. Within this narrow range, most of the observed light curve properties can be obtained in part, but none of the models can reproduce the entire light curve shape and absolute magnitude over the full 200 day comparison period. The observed lack of a plateau phase is explained in terms of a combination of small envelope mass and envelope helium enhancement. The final cobalt tail phase of the light curve can be reproduced only if the mass of explosively synthesized radioactive Ni-56 is small. The results presented here, in conjunction with the observed homogeneity among individual members of the supernova subclass, argue favorably for the O-Ne-Mg core collapse mechanism as an explanation for linear Type II supernovae. The Crab Nebula may arisen from such an explosion. Carbon deflagrations may lead to brighter events like SN 1979C. 62 refs.

  11. Modeling the World Health Organization Disability Assessment Schedule II using non-parametric item response models.

    PubMed

    Galindo-Garre, Francisca; Hidalgo, María Dolores; Guilera, Georgina; Pino, Oscar; Rojo, J Emilio; Gómez-Benito, Juana

    2015-03-01

    The World Health Organization Disability Assessment Schedule II (WHO-DAS II) is a multidimensional instrument developed for measuring disability. It comprises six domains (getting around, self-care, getting along with others, life activities and participation in society). The main purpose of this paper is the evaluation of the psychometric properties for each domain of the WHO-DAS II with parametric and non-parametric Item Response Theory (IRT) models. A secondary objective is to assess whether the WHO-DAS II items within each domain form a hierarchy of invariantly ordered severity indicators of disability. A sample of 352 patients with a schizophrenia spectrum disorder is used in this study. The 36 items WHO-DAS II was administered during the consultation. Partial Credit and Mokken scale models are used to study the psychometric properties of the questionnaire. The psychometric properties of the WHO-DAS II scale are satisfactory for all the domains. However, we identify a few items that do not discriminate satisfactorily between different levels of disability and cannot be invariantly ordered in the scale. In conclusion the WHO-DAS II can be used to assess overall disability in patients with schizophrenia, but some domains are too general to assess functionality in these patients because they contain items that are not applicable to this pathology. Copyright © 2014 John Wiley & Sons, Ltd.

  12. Eagle II: A prototype for multi-resolution combat modeling

    SciTech Connect

    Powell, D.R.; Hutchinson, J.L.

    1993-02-01

    Eagle 11 is a prototype analytic model derived from the integration of the low resolution Eagle model with the high resolution SIMNET model. This integration promises a new capability to allow for a more effective examination of proposed or existing combat systems that could not be easily evaluated using either Eagle or SIMNET alone. In essence, Eagle II becomes a multi-resolution combat model in which simulated combat units can exhibit both high and low fidelity behavior at different times during model execution. This capability allows a unit to behave in a highly manner only when required, thereby reducing the overall computational and manpower requirements for a given study. In this framework, the SIMNET portion enables a highly credible assessment of the performance of individual combat systems under consideration, encompassing both engineering performance and crew capabilities. However, when the assessment being conducted goes beyond system performance and extends to questions of force structure balance and sustainment, then SISMNET results can be used to ``calibrate`` the Eagle attrition process appropriate to the study at hand. Advancing technologies, changes in the world-wide threat, requirements for flexible response, declining defense budgets, and down-sizing of military forces motivate the development of manpower-efficient, low-cost, responsive tools for combat development studies. Eagle and SIMNET both serve as credible and useful tools. The integration of these two models promises enhanced capabilities to examine the broader, deeper, more complex battlefield of the future with higher fidelity, greater responsiveness and low overall cost.

  13. Eagle II: A prototype for multi-resolution combat modeling

    SciTech Connect

    Powell, D.R.; Hutchinson, J.L.

    1993-01-01

    Eagle 11 is a prototype analytic model derived from the integration of the low resolution Eagle model with the high resolution SIMNET model. This integration promises a new capability to allow for a more effective examination of proposed or existing combat systems that could not be easily evaluated using either Eagle or SIMNET alone. In essence, Eagle II becomes a multi-resolution combat model in which simulated combat units can exhibit both high and low fidelity behavior at different times during model execution. This capability allows a unit to behave in a highly manner only when required, thereby reducing the overall computational and manpower requirements for a given study. In this framework, the SIMNET portion enables a highly credible assessment of the performance of individual combat systems under consideration, encompassing both engineering performance and crew capabilities. However, when the assessment being conducted goes beyond system performance and extends to questions of force structure balance and sustainment, then SISMNET results can be used to calibrate'' the Eagle attrition process appropriate to the study at hand. Advancing technologies, changes in the world-wide threat, requirements for flexible response, declining defense budgets, and down-sizing of military forces motivate the development of manpower-efficient, low-cost, responsive tools for combat development studies. Eagle and SIMNET both serve as credible and useful tools. The integration of these two models promises enhanced capabilities to examine the broader, deeper, more complex battlefield of the future with higher fidelity, greater responsiveness and low overall cost.

  14. LHC phenomenology of SO(10) models with Yukawa unification. II.

    NASA Astrophysics Data System (ADS)

    Anandakrishnan, Archana; Bryant, B. Charles; Raby, Stuart

    2014-07-01

    In this paper we study Yukawa-unified SO(10) supersymmetric (SUSY) grand unified theories (GUTs) with two types of SO(10) boundary conditions: (i) universal gaugino masses and (ii) nonuniversal gaugino masses with effective "mirage" mediation. With these boundary conditions, we perform a global χ2 analysis to obtain the parameters consistent with 11 low energy observables, including the top, bottom, and tau masses. Both boundary conditions have universal scalar masses and "just so" splitting for the up- and down-type Higgs masses. In these models, the third family scalars are lighter than the first two families and the gauginos are lighter than all the scalars. We therefore focus on the gluino phenomenology in these models. In particular, we estimate the lowest allowed gluino mass in our models coming from the most recent LHC data and compare this to limits obtained using simplified models. We find that the lower bound on Mg ˜ in Yukawa-unified SO(10) SUSY GUTs is generically ˜1.2 TEV at the 1σ level unless there is considerable degeneracy between the gluino and the lightest supersymmetric particle, in which case the bounds are much weaker. Hence many of our benchmark points are not ruled out by the present LHC data and are still viable models which can be tested at LHC 14.

  15. Modeling fluid dynamics on type II quantum computers

    NASA Astrophysics Data System (ADS)

    Scoville, James; Weeks, David; Yepez, Jeffrey

    2006-03-01

    A quantum algorithm is presented for modeling the time evolution of density and flow fields governed by classical equations, such as the diffusion equation, the nonlinear Burgers equation, and the damped wave equation. The algorithm is intended to run on a type-II quantum computer, a parallel quantum computer consisting of a lattice of small type I quantum computers undergoing unitary evolution and interacting via information interchanges represented by an orthogonal matrices. Information is effectively transferred between adjacent quantum computers over classical communications channels because of controlled state demolition following local quantum mechanical qubit-qubit interactions within each quantum computer. The type-II quantum algorithm presented in this paper describes a methodology for generating quantum logic operations as a generalization of classical operations associated with finite-point group symmetries. The quantum mechanical evolution of multiple qubits within each node is described. Presented is a proof that the parallel quantum system obeys a finite-difference quantum Boltzman equation at the mesoscopic scale, leading in turn to various classical linear and nonlinear effective field theories at the macroscopic scale depending on the details of the local qubit-qubit interactions.

  16. Type II Supernovae: Model Light Curves and Standard Candle Relationships

    NASA Astrophysics Data System (ADS)

    Kasen, Daniel; Woosley, S. E.

    2009-10-01

    A survey of Type II supernovae explosion models has been carried out to determine how their light curves and spectra vary with their mass, metallicity, and explosion energy. The presupernova models are taken from a recent survey of massive stellar evolution at solar metallicity supplemented by new calculations at subsolar metallicity. Explosions are simulated by the motion of a piston near the edge of the iron core and the resulting light curves and spectra are calculated using full multi-wavelength radiation transport. Formulae are developed that describe approximately how the model observables (light curve luminosity and duration) scale with the progenitor mass, explosion energy, and radioactive nucleosynthesis. Comparison with observational data shows that the explosion energy of typical supernovae (as measured by kinetic energy at infinity) varies by nearly an order of magnitude—from 0.5 to 4.0 × 1051 ergs, with a typical value of ~0.9 × 1051 ergs. Despite the large variation, the models exhibit a tight relationship between luminosity and expansion velocity, similar to that previously employed empirically to make SNe IIP standardized candles. This relation is explained by the simple behavior of hydrogen recombination in the supernova envelope, but we find a sensitivity to progenitor metallicity and mass that could lead to systematic errors. Additional correlations between light curve luminosity, duration, and color might enable the use of SNe IIP to obtain distances accurate to ~20% using only photometric data.

  17. Comparison with CLPX II airborne data using DMRT model

    USGS Publications Warehouse

    Xu, X.; Liang, D.; Andreadis, K.M.; Tsang, L.; Josberger, E.G.

    2009-01-01

    In this paper, we considered a physical-based model which use numerical solution of Maxwell Equations in three-dimensional simulations and apply into Dense Media Radiative Theory (DMRT). The model is validated in two specific dataset from the second Cold Land Processes Experiment (CLPX II) at Alaska and Colorado. The data were all obtain by the Ku-band (13.95GHz) observations using airborne imaging polarimetric scatterometer (POLSCAT). Snow is a densely packed media. To take into account the collective scattering and incoherent scattering, analytical Quasi-Crystalline Approximation (QCA) and Numerical Maxwell Equation Method of 3-D simulation (NMM3D) are used to calculate the extinction coefficient and phase matrix. DMRT equations were solved by iterative solution up to 2nd order for the case of small optical thickness and full multiple scattering solution by decomposing the diffuse intensities into Fourier series was used when optical thickness exceed unity. It was shown that the model predictions agree with the field experiment not only co-polarization but also cross-polarization. For Alaska region, the input snow structure data was obtain by the in situ ground observations, while for Colorado region, we combined the VIC model to get the snow profile. ??2009 IEEE.

  18. TYPE II SUPERNOVAE: MODEL LIGHT CURVES AND STANDARD CANDLE RELATIONSHIPS

    SciTech Connect

    Kasen, Daniel; Woosley, S. E.

    2009-10-01

    A survey of Type II supernovae explosion models has been carried out to determine how their light curves and spectra vary with their mass, metallicity, and explosion energy. The presupernova models are taken from a recent survey of massive stellar evolution at solar metallicity supplemented by new calculations at subsolar metallicity. Explosions are simulated by the motion of a piston near the edge of the iron core and the resulting light curves and spectra are calculated using full multi-wavelength radiation transport. Formulae are developed that describe approximately how the model observables (light curve luminosity and duration) scale with the progenitor mass, explosion energy, and radioactive nucleosynthesis. Comparison with observational data shows that the explosion energy of typical supernovae (as measured by kinetic energy at infinity) varies by nearly an order of magnitude-from 0.5 to 4.0 x 10{sup 51} ergs, with a typical value of approx0.9 x 10{sup 51} ergs. Despite the large variation, the models exhibit a tight relationship between luminosity and expansion velocity, similar to that previously employed empirically to make SNe IIP standardized candles. This relation is explained by the simple behavior of hydrogen recombination in the supernova envelope, but we find a sensitivity to progenitor metallicity and mass that could lead to systematic errors. Additional correlations between light curve luminosity, duration, and color might enable the use of SNe IIP to obtain distances accurate to approx20% using only photometric data.

  19. Efficient three-dimensional global models for climate studies - Models I and II

    NASA Technical Reports Server (NTRS)

    Russel, G.; Rind, D.; Lacis, A.; Travis, L.; Stone, P.; Lebedeff, S.; Ruedy, R.; Hansen, J.

    1983-01-01

    Climate modeling based on numerical solution of the fundamental equations for atmospheric structure and motion permits the explicit modeling of physical processes in the climate system and the natural treatment of interactions and feedbacks among parts of the system. The main difficulty concerning this approach is related to the computational requirements. The present investigation is concerned with the development of a grid-point model which is programmed so that both horizontal and vertical resolutions can easily be changed. Attention is given to a description of Model I, the performance of sensitivity experiments by varying parameters, the definition of an improved Model II, and a study of the dependence of climate simulation on resolution with Model II. It is shown that the major features of global climate can be simulated reasonably well with a horizontal resolution as coarse as 1000 km. Such a resolution allows the possibility of long-range climate studies with moderate computer resources.

  20. Photoionization models of the CALIFA H II regions. I. Hybrid models

    NASA Astrophysics Data System (ADS)

    Morisset, C.; Delgado-Inglada, G.; Sánchez, S. F.; Galbany, L.; García-Benito, R.; Husemann, B.; Marino, R. A.; Mast, D.; Roth, M. M.

    2016-10-01

    Photoionization models of H ii regions require as input a description of the ionizing spectral energy distribution (SED) and of the gas distribution, in terms of ionization parameter U and chemical abundances (e.g., O/H and N/O).A strong degeneracy exists between the hardness of the SED and U, which in turn leads to high uncertainties in the determination of the other parameters, including abundances. One way to resolve the degeneracy is to fix one of the parameters using additional information. For each of the ~20 000 sources of the CALIFA H ii regions catalog, a grid of photoionization models is computed assuming the ionizing SED to be described by the underlying stellar population obtained from spectral synthesis modeling. The ionizing SED is then defined as the sum of various stellar bursts of different ages and metallicities. This solves the degeneracy between the shape of the ionizing SED and U. The nebular metallicity (associated with O/H) is defined using the classical strong line method O3N2 (which gives our models the status of "hybrids"). The remaining free parameters are the abundance ratio N/O and the ionization parameter U, which are determined by looking for the model fitting [N ii]/Hα and [O iii]/Hβ. The models are also selected to fit [O ii]/Hβ. This process leads to a set of ~3200 models that reproduce the three observations simultaneously. We find that the regions associated with young stellar bursts (i.e., ionized by OB stars) are affected by leaking of ionizing photons,the proportion of escaping photons having a median of 80%. The set of photoionization models satisfactorily reproduces the electron temperature derived from the [O iii]λ4363/5007 line ratio. We determine new relations between the nebular parameters, like the ionization parameter U and the [O ii]/[O iii] or [S ii]/[S iii] line ratios. A new relation between N/O and O/H is obtained, mostly compatible with previous empirical determinations (and not with previous results obtained

  1. An Analytic Model of Dusty, Stratified, Spherical H II Regions

    NASA Astrophysics Data System (ADS)

    Rodríguez-Ramírez, J. C.; Raga, A. C.; Lora, V.; Cantó, J.

    2016-12-01

    We study analytically the effect of radiation pressure (associated with photoionization processes and with dust absorption) on spherical, hydrostatic H ii regions. We consider two basic equations, one for the hydrostatic balance between the radiation-pressure components and the gas pressure, and another for the balance among the recombination rate, the dust absorption, and the ionizing photon rate. Based on appropriate mathematical approximations, we find a simple analytic solution for the density stratification of the nebula, which is defined by specifying the radius of the external boundary, the cross section of dust absorption, and the luminosity of the central star. We compare the analytic solution with numerical integrations of the model equations of Draine, and find a wide range of the physical parameters for which the analytic solution is accurate.

  2. Type II seesaw model and multilepton signatures at hadron colliders

    NASA Astrophysics Data System (ADS)

    Mitra, Manimala; Niyogi, Saurabh; Spannowsky, Michael

    2017-02-01

    We investigate multilepton signatures, arising from the decays of doubly charged and singly charged Higgs bosons in the Type II seesaw model. Depending on the vacuum expectation value of the triplet vΔ , the doubly and singly charged Higgs bosons can decay into a large variety of multilepton final states. We explore all possible decay modes corresponding to different regimes of vΔ that generate distinguishing four and five leptonic signatures. We focus on the 13 TeV Large Hadron Collider (LHC) and further extend the study to a very high energy proton-proton collider (VLHC) with a center-of-mass energy of 100 TeV. We find that a doubly charged Higgs boson of masses around 375 GeV can be discovered at immediate LHC runs. A heavier mass of 630 GeV can instead be discovered at the high-luminosity run of the LHC or at the VLHC with 30 fb-1 .

  3. Models and Analysis of Wire Explosions Using TRAC II Simulations

    SciTech Connect

    Pekker, A.; Reisman, D.B.

    1999-09-10

    In order to understand the dynamics of Z-pinch imposions of thin wires in pulse-power accelerators, it is necessary to understand the physical process by which the initially solid wires are converted into plasma by rising current. For this purpose, we model wire explosions using TRAC II, a two-dimensional MHD code, in three distinct cases: pure tungsten, impure tungsten, and gold-plated tungsten. We compare our results--overall picture of the process, corona linear density, corona mass, and core expansion rate--to actual experiments performed at Sandia National Laboratory and Cornell University and present some explanations for the disagreements between our model and experimental observations. In Chapter 1, we discuss model results for several current waveforms (consisting of a 5 kA 50-150 ns pre-pulse and 80 kA 80 ns main pulse) for a pure tungsten wire, showing that the initial temperature of the wire does not affect the dynamics of the explosion. This suggests that different experimental results for unheated and preheated tungsten wires are due to the expulsion of impurities in the preheated wire and not to a change in the material properties of tungsten. To match the experimental set-up more accurately, we model the explosion of a tungsten wire with impurities in Chapter 2. The overall process predicted by the model agrees with experiment, namely the shunting of the current through the impurities region before tungsten expansion begins; however, quantitative results disagree with experimental observations mostly because of the extreme shunting of the current through the impurities in our model. Finally, in Chapter 3, we compare the explosions in gold-plated tungsten, pure tungsten, and pure gold wires under high (100 kA in 60 ns) and low (2 kA in 270 ns) currents, finding general agreement with experiment in the high-current case and a disagreement by a factor of ten in the low-current case. In addition, due to the similar properties of the two metals, we find

  4. ThreadedComposite: A Mechanism for Building Concurrent and Parallel Ptolemy II Models

    DTIC Science & Technology

    2008-12-07

    ThreadedComposite: A Mechanism for Building Concurrent and Parallel Ptolemy II Models Edward A. Lee Electrical Engineering and Computer Sciences...Concurrent and Parallel Ptolemy II Models 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK...Instruments, and Toyota. ThreadedComposite: A Mechanism for Building Concurrent and Parallel Ptolemy II Models ∗ Edward A. Lee UC Berkeley eal

  5. Real-time C Code Generation in Ptolemy II for the Giotto Model of Computation

    DTIC Science & Technology

    2009-05-20

    Real-time C Code Generation in Ptolemy II for the Giotto Model of Computation Shanna-Shaye Forbes Electrical Engineering and Computer Sciences...MAY 2009 2. REPORT TYPE 3. DATES COVERED 00-00-2009 to 00-00-2009 4. TITLE AND SUBTITLE Real-time C Code Generation in Ptolemy II for the Giotto...periodic and there are multiple modes of operation. Ptolemy II is a university based open source modeling and simulation framework that supports model

  6. Heterogeneous Concurrent Modeling and Design in Java (Volume 1: Introduction to Ptolemy II)

    DTIC Science & Technology

    2008-04-01

    Heterogeneous Concurrent Modeling and Design in Java (Volume 1: Introduction to Ptolemy II) Christopher Brooks Edward A. Lee Xiaojun Liu Stephen...2008 4. TITLE AND SUBTITLE Heterogeneous Concurrent Modeling and Design in Java (Volume 1: Introduction to Ptolemy II) 5a. CONTRACT NUMBER 5b... PTOLEMY II HETEROGENEOUS CONCURRENT MODELING AND DESIGN IN JAVA Edited by: Christopher Brooks, Edward A. Lee, Xiaojun Liu, Steve Neuendorffer, Yang

  7. Higgs potential in the type II seesaw model

    SciTech Connect

    Arhrib, A.; Benbrik, R.; Chabab, M.; Rahili, L.; Ramadan, J.; Moultaka, G.; Peyranere, M. C.

    2011-11-01

    The standard model Higgs sector, extended by one weak gauge triplet of scalar fields with a very small vacuum expectation value, is a very promising setting to account for neutrino masses through the so-called type II seesaw mechanism. In this paper we consider the general renormalizable doublet/triplet Higgs potential of this model. We perform a detailed study of its main dynamical features that depend on five dimensionless couplings and two mass parameters after spontaneous symmetry breaking, and highlight the implications for the Higgs phenomenology. In particular, we determine (i) the complete set of tree-level unitarity constraints on the couplings of the potential and (ii) the exact tree-level boundedness from below constraints on these couplings, valid for all directions. When combined, these constraints delineate precisely the theoretically allowed parameter space domain within our perturbative approximation. Among the seven physical Higgs states of this model, the mass of the lighter (heavier) CP{sub even} state h{sup 0} (H{sup 0}) will always satisfy a theoretical upper (lower) bound that is reached for a critical value {mu}{sub c} of {mu} (the mass parameter controlling triple couplings among the doublet/triplet Higgses). Saturating the unitarity bounds, we find an upper bound m{sub h}{sup 0} or approx. {mu}{sub c} and {mu} < or approx. {mu}{sub c}. In the first regime the Higgs sector is typically very heavy, and only h{sup 0} that becomes SM-like could be accessible to the LHC. In contrast, in the second regime, somewhat overlooked in the literature, most of the Higgs sector is light. In particular, the heaviest state H{sup 0} becomes SM-like, the lighter states being the CP{sub odd} Higgs, the (doubly) charged Higgses, and a decoupled h{sup 0}, possibly

  8. Multiscale model of light harvesting by photosystem II in plants

    PubMed Central

    Amarnath, Kapil; Bennett, Doran I. G.; Schneider, Anna R.; Fleming, Graham R.

    2016-01-01

    The first step of photosynthesis in plants is the absorption of sunlight by pigments in the antenna complexes of photosystem II (PSII), followed by transfer of the nascent excitation energy to the reaction centers, where long-term storage as chemical energy is initiated. Quantum mechanical mechanisms must be invoked to explain the transport of excitation within individual antenna. However, it is unclear how these mechanisms influence transfer across assemblies of antenna and thus the photochemical yield at reaction centers in the functional thylakoid membrane. Here, we model light harvesting at the several-hundred-nanometer scale of the PSII membrane, while preserving the dominant quantum effects previously observed in individual complexes. We show that excitation moves diffusively through the antenna with a diffusion length of 50 nm until it reaches a reaction center, where charge separation serves as an energetic trap. The diffusion length is a single parameter that incorporates the enhancing effect of excited state delocalization on individual rates of energy transfer as well as the complex kinetics that arise due to energy transfer and loss by decay to the ground state. The diffusion length determines PSII’s high quantum efficiency in ideal conditions, as well as how it is altered by the membrane morphology and the closure of reaction centers. We anticipate that the model will be useful in resolving the nonphotochemical quenching mechanisms that PSII employs in conditions of high light stress. PMID:26787911

  9. Implementing a predictive modeling program, part II: Use of motivational interviewing in a predictive modeling program.

    PubMed

    Calhoun, Jean; Admire, Kaye S

    2005-01-01

    This is the second article of a two-part series about issues encountered in implementing a predictive modeling program. Part I looked at how to effectively implement a program and discussed helpful hints and lessons learned for case managers who are required to change their approach to patients. In Part II, we discuss the readiness to change model, examine the spirit of motivational interviewing and related techniques, and explore how motivational interviewing is different from more traditional interviewing and assessment methods.

  10. Modeling of fluidized-bed combustion of coal: Phase II, final reports. Volume II. Detailed description of the model

    SciTech Connect

    Louis, J.F.; Tung, S.E.

    1980-10-01

    This document is the second of a seven volume series of our Phase II Final Report. This volume deals with detailed descriptions of the structure of each program member (subroutines and functions), the interrelation between the members of a submodel, and the interrelation between the various submodels as such. The systems model for fluidized bed combustors (FBC-II) consists of a systematic combination of the following interrelated areas: fluid mechanics and bubble growth, char combustion and associated kinetics for particle burnout, sulfur capture, NO/sub x/ formation and reduction, freeboard reactions, and heat transfer. Program outline is shown in Figure 1.1. Input variables (supplied by the user are inspected to check that they lie inside the allowed range of values and are input to the various routines as needed. The necessary physical and fluid mechanical properties are calculated and utilized in estimating char combustion and sulfur capture in the bed and the freeboard. NO/sub x/ and CO emissions are estimated by taking into account all relevant chemical reactions. A material and energy balance is made over the bed. Figure 1.1 shows a block diagram of the systems program. In this diagram, the overall structure of the FBC program is illustrated in terms of the various submodels that together constitute the systems program. A more detailed outline of the systems program is shown in Figure 1.2. In this figure, all important subroutine members of the FBC program are shown, and their linkage to each other, as well as to the main program is indicated. A description of the exact sequence in which these various routines are called at time of program execution is provided in Chapter 8 under the executive routine MAIN.

  11. Learning Objects, Type II Applications, and Embedded Pedagogical Models

    ERIC Educational Resources Information Center

    Gadanidis, George; Schindler, Karen

    2006-01-01

    In this paper we consider the extent to which learning objects that focus on higher level thinking might be seen as Type II applications, as defined by Maddux, Johnson, and Willis (2001). We conclude that learning objects are at best hybrid applications, with some Type I and some Type II characteristics. We also consider whether the educational…

  12. Unified Field Theoretical Models from Generalized Affine Geometries II

    NASA Astrophysics Data System (ADS)

    Cirilo-Lombardo, Diego Julio

    2011-06-01

    The space-time structure of the new Unified Field Theory presented in previous reference (Int. J. Theor. Phys. 49:1288-1301, 2010) is analyzed from its SL(2C) underlying structure in order to make precise the notion of minimal coupling. To this end, the framework is the language of tensors and particularly differential forms and the condition a priory of the existence of a potential for the torsion is relaxed. We shown trough exact cosmological solutions from this model, where the geometry is Euclidean R⊗ O 3˜ R⊗ SU(2), the relation between the space-time geometry and the structure of the gauge group. Precisely this relation is directly connected with the relation of the spin and torsion fields. The solution of this model is explicitly compared with our previous ones and we find that: (i) the torsion is not identified directly with the Yang Mills type strength field, (ii) there exists a compatibility condition connected with the identification of the gauge group with the geometric structure of the space-time: this fact lead the identification between derivatives of the scale factor a( τ) with the components of the torsion in order to allows the Hosoya-Ogura ansatz (namely, the alignment of the isospin with the frame geometry of the space-time), (iii) this compatibility condition precisely mark the fact that local gauge covariance, coordinate independence and arbitrary space time geometries are harmonious concepts and (iv) of two possible structures of the torsion the "tratorial" form (the only one studied here) forbids wormhole configurations, leading only, cosmological instanton space-time in eternal expansion.

  13. Radiation-hydrodynamical modelling of underluminous Type II plateau supernovae

    NASA Astrophysics Data System (ADS)

    Pumo, M. L.; Zampieri, L.; Spiro, S.; Pastorello, A.; Benetti, S.; Cappellaro, E.; Manicò, G.; Turatto, M.

    2017-01-01

    With the aim of improving our knowledge about the nature of the progenitors of low-luminosity Type II plateau supernovae (LL SNe IIP), we made radiation-hydrodynamical models of the well-sampled LL SNe IIP 2003Z, 2008bk and 2009md. For these three SNe, we infer explosion energies of 0.16-0.18 foe, radii at explosion of 1.8-3.5 × 1013 cm and ejected masses of 10-11.3 M⊙. The estimated progenitor mass on the main sequence is in the range ˜13.2-15.1 M⊙ for SN 2003Z and ˜11.4-12.9 M⊙ for SNe 2008bk and 2009md, in agreement with estimates from observations of the progenitors. These results together with those for other LL SNe IIP modelled in the same way enable us also to conduct a comparative study on this SN sub-group. The results suggest that (a) the progenitors of faint SNe IIP are slightly less massive and have less energetic explosions than those of intermediate-luminosity SNe IIP; (b) both faint and intermediate-luminosity SNe IIP originate from low-energy explosions of red (or yellow) supergiant stars of low to intermediate mass; (c) some faint objects may also be explained as electron-capture SNe from massive super-asymptotic giant branch stars; and (d) LL SNe IIP form the underluminous tail of the SNe IIP family, where the main parameter `guiding' the distribution seems to be the ratio of the total explosion energy to the ejected mass. Further hydrodynamical studies should be performed and compared to a more extended sample of LL SNe IIP before drawing any conclusion on the relevance of fall-back to this class of events.

  14. Heterogeneous Concurrent Modeling and Design in Java (Volume 3: Ptolemy II Domains)

    DTIC Science & Technology

    2008-04-15

    Heterogeneous Concurrent Modeling and Design in Java (Volume 3: Ptolemy II Domains) Christopher Brooks Edward A. Lee Xiaojun Liu Stephen Neuendorffer...TITLE AND SUBTITLE Heterogeneous Concurrent Modeling and Design in Java (Volume 3: Ptolemy II Domains) 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...State of California Micro Program, and the following companies: Agilent, Bosch, HSBC, Lockheed-Martin, National Instruments, and Toyota. PTOLEMY II

  15. User's Guide To CHEAP0 II-Economic Analysis of Stand Prognosis Model Outputs

    Treesearch

    Joseph E. Horn; E. Lee Medema; Ervin G. Schuster

    1986-01-01

    CHEAP0 II provides supplemental economic analysis capability for users of version 5.1 of the Stand Prognosis Model, including recent regeneration and insect outbreak extensions. Although patterned after the old CHEAP0 model, CHEAP0 II has more features and analytic capabilities, especially for analysis of existing and uneven-aged stands....

  16. Longitudinal Stability of the Beck Depression Inventory II: A Latent Trait-State-Occasion Model

    ERIC Educational Resources Information Center

    Wu, Pei-Chen

    2016-01-01

    In a six-wave longitudinal study with two cohorts (660 adolescents and 630 young adults), this study investigated the longitudinal stability of the Beck Depression Inventory II (BDI-II) using the Trait-State-Occasion (TSO) model. The results revealed that the full TSO model was the best fitting representation of the depression measured by the…

  17. Longitudinal Stability of the Beck Depression Inventory II: A Latent Trait-State-Occasion Model

    ERIC Educational Resources Information Center

    Wu, Pei-Chen

    2016-01-01

    In a six-wave longitudinal study with two cohorts (660 adolescents and 630 young adults), this study investigated the longitudinal stability of the Beck Depression Inventory II (BDI-II) using the Trait-State-Occasion (TSO) model. The results revealed that the full TSO model was the best fitting representation of the depression measured by the…

  18. MICS-Asia II: Modeling gaseous pollutants and evaluating an advanced modeling system over East Asia

    NASA Astrophysics Data System (ADS)

    Fu, Joshua S.; Jang, Carey J.; Streets, David G.; Li, Zuopan; Kwok, Roger; Park, Rokjin; Han, Zhiwei

    An advanced modeling system with a "one-atmosphere" perspective, Models-3/Community Multi-scale Air Quality (CMAQ) modeling system, driven by MM5/NCEP reanalysis data as the meteorology, and GEOS-Chem outputs as boundary values was applied to simulate the O 3, and other gaseous pollutants (SO 2 and NO 2) evolution among other atmospheric chemicals for July 2001. Comparisons had been made with other models in the MICS-II exercise for the same period. Statistics of both monthly and daily means show that the model skill is very good in reproducing O 3 and SO 2 with small to moderate RMSE. The model species capture the day-to-day and spatial variability of the observations. The same O 3 model concentrations that overpredict most of the EANET observations in the MICS-II study may have underpredicted ones from monitoring networks in Beijing area that is not included in this paper. Vertical O 3 profiles at 4 ozonesonde sites are well predicted in July 2001. In fact, our model is among the best of those MICS-II models within the 2-km surface layer. The meteorology near surface and lower troposphere is well reproduced. Compared to SO 2 and O 3, the NO 2 gas concentrations are simulated less well, but the correlation coefficient is still significant. The choice of reanalysis meteorological fields and different boundary conditions generated by different global models may result in diverse spatial patterns exhibited by MICS-II models and ours. Our spatial distributions of O 3 shows a high concentration patch covering Beijing, a moderate to high pattern across Korea and Japan Sea, and a low but extensive pattern enclosing southern China, Taiwan, and East Sea. Extension of the pattern to southern China coincides with the existence of pollution problems in Guangdong and Taiwan, but overprediction of O 3 over the region deserves further improvement by various factors. One of them can be the grid resolution to resolve the complex orography in or close to the ocean. Another factor

  19. An energetic comparison of different models for the oxygen evolving complex of photosystem II.

    PubMed

    Siegbahn, Per E M

    2009-12-30

    The computed total energy from a cluster model DFT calculation is used to discriminate between different suggested models for the oxygen evolving complex of photosystem II. The comparison between different structures rules out several suggestions. Only one suggested structure remains.

  20. Juno/JEDI observations of 0.01 to >10 MeV energetic ions in the Jovian auroral regions: Anticipating a source for polar X-ray emission

    NASA Astrophysics Data System (ADS)

    Haggerty, D. K.; Mauk, B. H.; Paranicas, C. P.; Clark, G.; Kollmann, P.; Rymer, A. M.; Bolton, S. J.; Connerney, J. E. P.; Levin, S. M.

    2017-07-01

    After a successful orbit insertion, the Juno spacecraft completed its first 53.5 day orbit and entered a very low altitude perijove with the full scientific payload operational for the first time on 27 August 2016. The Jupiter Energetic particle Detector Instrument measured ions and electrons over the auroral regions and through closest approach, with ions measured from 0.01 to >10 MeV, depending on species. This report focuses on the composition of the energetic ions observed during the first perijove of the Juno mission. Of particular interest are the ions that precipitate from the magnetosphere onto the polar atmosphere and ions that are accelerated locally by Jupiter's powerful auroral processes. We report preliminary findings on the spatial variations, species, including energy and pitch angle distributions throughout the prime science region during the first orbit of the Juno mission. The prime motivation for this work was to examine the heavy ions that are thought to be responsible for the observed polar X-rays. Jupiter Energetic particle Detector Instrument (JEDI) did observe precipitating heavy ions with energies >10 MeV, but for this perijove the intensities were far below those needed to account for previously observed polar X-ray emissions. During this survey we also found an unusual signal of ions between oxygen and sulfur. We include here a report on what appears to be a transitory observation of magnesium, or possibly sodium, at MeV energies through closest approach.

  1. Analytic Models for Radiation Induced Loss in Optical Fibers II. A Physical Model,

    DTIC Science & Technology

    1984-06-01

    and identify by Mock number) PIEL GRUP UB.GR. Optical fibers Analytical models Radiation effects 19. ABSTRACT (ConinueII. anl mwr,f fneciua,, and...conditions specified in the derivation of the equations existed during the irradiations. This is because the functional form of the equations is not...tion is not necessarily incorrect. If one assumes a relatively simple form of re- covery as a function of time, such as an exponential recovery, it can

  2. Modeling of adsorption and ultrasonic desorption of cadmium(II) and zinc(II) on local bentonite.

    PubMed

    Lacin, Oral; Bayrak, Bahar; Korkut, Ozlem; Sayan, Enes

    2005-12-15

    The adsorption and ultrasonic desorption of toxic heavy metal cations (i.e., Cd(II) and Zn(II)) on natural bentonite have been modeled with the aid of a factorial design approach. The ability of untreated bentonite to remove Cd(II) and Zn(II) from aqueous and acidic solutions at different pH values has been studied for different metal concentrations by varying the amount of adsorbent, temperature, stirring speed, and contact time. The same factors, except stirring speed and metal concentration, were applied in desorption study. Ultrasound power was used for desorption instead of stirring speed. A flame atomic absorption spectrometer was used to measure the cadmium and zinc concentration before and after both experimental study. The highest adsorption for Zn and Cd was 99.85 and 96.84%, respectively, and the highest desorption for Zn and Cd obtained was 66.57 and 51.37%, respectively. It is believed that the models obtained for adsorption and desorption may provide a background for detailed mechanism searches and pilot and industrial scale applications.

  3. Anion complexes of Cu(II) and Co(II) bovine carbonic anhydrase as models for the copper site of blue copper proteins.

    PubMed

    Morpurgo, L; Finazzi Agrò, A; Rotilio, G; Mondovì, B

    1976-05-01

    1. The presence of two intense transitions in the optical absorption spectrum of the sulfide and 2-mercaptoethanol complexes of Cu(II) and Co(II)-substituted bovine carbonic anhydrase suggest that charge-transfer interactions between sulfur and an acceptor group of the protein play an important role in the stabilization of these complexes. 2. The spectra of Co(II) bovine carbonic anhydrase sulfides are very similar to the spectrum of Co(II) stellacyanin whilst the spectra of the corresponding Cu(II) enzymes are considerably different. A possible explanation is that Cu(II) is pentacoordinate in native stellacyanin unlike Cu(II) bovine carbonic anhydrase sulfides and Co(II) enzymes. Tetrahedral Co(II) stellacyanin is proposed as a model of the reduced copper site.

  4. Single-arm phase II trial design under parametric cure models.

    PubMed

    Wu, Jianrong

    2015-01-01

    The current practice of designing single-arm phase II survival trials is limited under the exponential model. Trial design under the exponential model may not be appropriate when a portion of patients are cured. There is no literature available for designing single-arm phase II trials under the parametric cure model. In this paper, a test statistic is proposed, and a sample size formula is derived for designing single-arm phase II trials under a class of parametric cure models. Extensive simulations showed that the proposed test and sample size formula perform very well under different scenarios. Copyright © 2015 John Wiley & Sons, Ltd.

  5. Single-Arm Phase II Trial Design Under Parametric Cure Models

    PubMed Central

    Wu, Jianrong

    2015-01-01

    The current practice of designing single-arm phase II survival trials is limited under the exponential model. Trial design under the exponential model may not be appropriate when a portion of patients are cured. There is no literature available for designing single-arm phase II trials under the parametric cure model. In this article, a test statistic is proposed, and a sample size formula is derived for designing single-arm phase II trials under a class of parametric cure models. Extensive simulations showed that the proposed test and sample size formula perform very well under different scenarios. PMID:25846141

  6. Modeling adsorption of copper(II), cadmium(II) and lead(II) on purified humic acid

    SciTech Connect

    Liu, A.; Gonzalez, R.D.

    2000-04-18

    In this study, a system consisting of Pb, Cu and Cd as typical heavy metal pollutants, and purified Aldrich humic acid as a representative of natural organic materials were selected as prototypes to model the environmental system. The effect of environmental factors such as pH, salinity, and concentration on the interaction between metals and humic acid were investigated in detail. The experimental results show that pH and ionic strength are the most important variables in controlling metal adsorption on humic acid. The results also show a high complexation capacity of humic acid for the metals, especially Cu and Pb. The strength of binding of the three metals is in the sequence of Pb > Cu > Cd. A theoretical model featured by surface complexation reactions and double layer theory combined with the Poisson-Boltzmann equation was applied to simulate the experimental data. Titration data of humic acid with NaOH and Ba(OH){sub 2} were used as concentrations of strong and weak acid groups on HA and the input data for the model calculations. Intrinsic adsorption constants and capacitance are estimated based on literature values and optimized to obtain the best agreement between the experimental and the model results. The model was also used to predict surface properties such as the speciation of the metals adsorbed on humic acid. Good agreement between theoretical modeling results and experimental data suggests the applicability of the theoretical model to this system. Given these parameters, theoretical calculations obtained using the model proposed in this study can give a detailed picture of the actual environmental conditions. Also, the model calculations will help in the evaluation of the actual toxicity of heavy metal pollutants in the aquasystem.

  7. Three-dimensional energy-minimized model of human type II "Smith" collagen microfibril.

    PubMed

    Chen, J M; Sheldon, A; Pincus, M R

    1995-06-01

    A procedure is described for constructing a three-dimensional model of fibril-forming human type II collagen based on the "Smith" microfibril model. This model is a complex of five individual collagen triple-helical molecules, and is based on known structural parameters for collagen. Both experimental and theoretical data were used as constraints to guide the modeling. The resulting fibril model for type II collagen is in agreement with both physical and chemical characteristics produced by experimental staining patterns of type II fibrils. Some advantages of the type II model are that the stereochemistry of all the sidechain groups is accounted for, and specific atomic interactions can now be studied. This model is useful for: development of therapeutics for collagen related diseases; development of synthetic collagen tissues; design of chemical reagents (i.e., tanning agents) to treat collagen-related products; and study of the structural and functional aspects of type II collagen. Described is the procedure by which the Smith microfibril of type II collagen was developed using molecular modeling tools, validation of the model by comparison to electron-microscopic images of fibril staining patterns, and some applications of this microfibril model.

  8. Molecular Models of Ruthenium(II) Organometallic Complexes

    ERIC Educational Resources Information Center

    Coleman, William F.

    2007-01-01

    This article presents the featured molecules for the month of March, which appear in the paper by Ozerov, Fafard, and Hoffman, and which are related to the study of the reactions of a number of "piano stool" complexes of ruthenium(II). The synthesis of compound 2a offers students an alternative to the preparation of ferrocene if they are only…

  9. Molecular Models of Ruthenium(II) Organometallic Complexes

    ERIC Educational Resources Information Center

    Coleman, William F.

    2007-01-01

    This article presents the featured molecules for the month of March, which appear in the paper by Ozerov, Fafard, and Hoffman, and which are related to the study of the reactions of a number of "piano stool" complexes of ruthenium(II). The synthesis of compound 2a offers students an alternative to the preparation of ferrocene if they are only…

  10. MICS-Asia II: The model intercomparison study for Asia Phase II methodology and overview of findings

    NASA Astrophysics Data System (ADS)

    Carmichael, G. R.; Sakurai, T.; Streets, D.; Hozumi, Y.; Ueda, H.; Park, S. U.; Fung, C.; Han, Z.; Kajino, M.; Engardt, M.; Bennet, C.; Hayami, H.; Sartelet, K.; Holloway, T.; Wang, Z.; Kannari, A.; Fu, J.; Matsuda, K.; Thongboonchoo, N.; Amann, M.

    Results from the Model Intercomparison Study Asia Phase II (MICS-Asia II) are presented. Nine different regional modeling groups simulated chemistry and transport of ozone (O 3), secondary aerosol, acid deposition, and associated precursors, using common emissions and boundary conditions derived from a global model. Four-month-long periods, representing 2 years and three seasons (i.e., March, July, and December in 2001, and March in 2002), are analyzed. New observational data, obtained under the EANET (the Acid Deposition Monitoring Network in East Asia) monitoring program, were made available for this study, and these data provide a regional database to compare with model simulations. The analysis focused around seven subject areas: O 3 and related precursors, aerosols, acid deposition, global inflow of pollutants and precursor to Asia, model sensitivities to aerosol parameterization, analysis of emission fields, and detailed analyses of individual models, each of which is presented in a companion paper in this issue of Atmospheric Environment. This overview discusses the major findings of the study, as well as information on common emissions, meteorological conditions, and observations.

  11. Stark II and physician compensation models: integrating business and legal issues.

    PubMed

    Pursell, David; Marsh, Jennifer; Thompson, David; Potter, Keith

    2005-01-01

    In March of 2004, the Centers for Medicare & Medicaid Services released new regulations that interpreted the Federal Physician Self Referral Act, otherwise known as Stark II. The new regulations, commonly referred to as the Phase II regulations, must be carefully considered when structuring physician compensation models. Stark II generally holds that physicians may not make a referral for designated health services to an entity with which they have a direct or indirect financial relationship. This Article outlines the provisions of Stark II that are applicable to physician compensation methodologies. In addition, the authors evaluate hypothetical transactions involving physician groups seeking viable compensation schemes and explore the validity and risks of each.

  12. Modeling of Copper(II), Cadmium(II), and Lead(II) Adsorption on Red Mud from Metal-EDTA Mixture Solutions.

    PubMed

    Güçlü; Apak

    2000-08-15

    The adsorption of toxic heavy metal cations, i.e., Cu(II), Cd(II), and Pb(II), from metal-EDTA mixture solutions on a composite adsorbent having a heterogeneous surface, i.e., bauxite waste red mud, has been investigated and modeled with the aid of a modified surface complexation approach in respect to pH and complexant dependency of heavy metal adsorption. EDTA was selected as the modeling ligand in view of its wide usage as an anthropogenic chelating agent and abundance in natural waters. The adsorption experiments were conducted for metal salts (nitrates), metal-EDTA complexes alone, or in mixtures containing (metal+metal-EDTA). The adsorption equilibrium constants for the metal ions and metal-EDTA complexes were calculated. For all studied cases, the solid adsorbent phase concentrations of the adsorbed metal and metal-EDTA complexes were found by using the derived model equations with excellent compatibility of experimental and theoretically generated adsorption isotherms. The model was useful for metal and metal-EDTA mixture solutions either at their natural pH of equilibration with the sorbent, or after pH elevation with NaOH titration up to a certain pH. Thus adsorption of every single species (M(2+) or MY(2-)) or of possible mixtures (M(2+)+MY(2-)) at natural pH or after NaOH titration could be calculated by the use of simple quadratic model equations, once the initial concentrations of the corresponding species, i.e., [M(2+)](0) or [MY(2-)](0), were known. The compatibility of theoretical and experimental data pairs of adsorbed species concentrations was verified by means of nonlinear regression analysis. The findings of this study can be further developed so as to serve environmental risk assessment concerning the expansion of a heavy metal contaminant plume with groundwater move ment in soil consisting of hydrated-oxide type minerals. Copyright 2000 Academic Press.

  13. Computational evaluation of unsaturated carbonitriles as neutral receptor model for beryllium(II) recognition.

    PubMed

    Rosli, Ahmad Nazmi; Ahmad, Mohd Rais; Alias, Yatimah; Zain, Sharifuddin Md; Lee, Vannajan Sanghiran; Woi, Pei Meng

    2014-12-01

    Design of neutral receptor molecules (ionophores) for beryllium(II) using unsaturated carbonitrile models has been carried out via density functional theory, G3, and G4 calculations. The first part of this work focuses on gas phase binding energies between beryllium(II) and 2-cyano butadiene (2-CN BD), 3-cyano propene (3-CN P), and simpler models with two separate fragments; acrylonitrile and ethylene. Interactions between beryllium(II) and cyano nitrogen and terminal olefin in the models have been examined in terms of geometrical changes, distribution of charge over the entire π-system, and rehybridization of vinyl carbon orbitals. NMR shieldings and vibrational frequencies probed charge centers and strength of interactions. The six-membered cyclic complexes have planar structures with the rehybridized carbon slightly out of plane (16° in 2-CN BD). G3 results show that in 2-CN BD complex participation of vinyl carbon further stabilizes the cyclic adduct by 16.3 kcal mol(-1), whereas, in simpler models, interaction between beryllium(II) and acetonitrile is favorable by 46.4 kcal mol(-1) compared with that of ethylene. The terminal vinyl carbon in 2-CN BD rehybridizes to sp (3) with an increase of 7 % of s character to allow interaction with beryllium(II). G4 calculations show that the Be(II) and 2-CN BD complex is more strongly bound than those with Mg(II) and Ca(II) by 98.5 and 139.2 kcal mol(-1) (-1), respectively. QST2 method shows that the cyclic and acyclic forms of Be(II)-2-CN BD complexes are separated by 12.3 kcal mol(-1) barrier height. Overlap population analysis reveals that Ca(II) can be discriminated based on its tendency to form ionic interaction with the receptor models.

  14. Peptidic models for the binding of Pb(II), Bi(III) and Cd(II) to mononuclear thiolate binding sites.

    PubMed

    Matzapetakis, Manolis; Ghosh, Debdip; Weng, Tsu-Chien; Penner-Hahn, James E; Pecoraro, Vincent L

    2006-10-01

    Herein, we evaluate the binding of Pb(II) and Bi(III) to cysteine-substituted versions of the TRI peptides [AcG-(LKALEEK)4G-NH2] which have previously been shown to bind Hg(II) and Cd(II) in unusual geometries as compared with small-molecule thiol ligands in aqueous solutions. Studies of Pb(II) and Bi(III) with the peptides give rise to complexes consistent with the metal ions bound to three sulfur atoms with M-S distances of 2.63 and 2.54 A, respectively. Competition experiments between the metal ions Pb(II), Cd(II), Hg(II) and Bi(III) for the peptides show that Hg(II) has the highest affinity, owing to the initial formation of the extremely strong HgS2 bond. Cd(II) and Pb(II) have comparable binding affinities at pH > 8, while Bi(III) displays the weakest affinity, following the model, M(II) + (TRI LXC)3(3-) --> M(II)(TRI LXC)3(-). While the relevant equilibria for Hg(II) binding to the TRI peptides corresponds to a strong first step forming Hg(TRI LXC)2(HTRI LXC), followed by a single deprotonation to give Hg(TRI LXC)3(-), the binding of Cd(II) and Pb(II) is consistent with initial formation of M(II)(TRI LXC)(HTRI LXC)2 (+) at pH < 5 followed by a two-proton dissociation step (pK(a2)) yielding M(II)(TRI LXC)3(-). Pb(II)(TRI LXC)(HTRI LXC)2(+) converts to Pb(II)(TRI LXC)3(-) at slightly lower pH values than the corresponding Cd(II)-peptide complexes. In addition, Pb(II) displays a lower pK (a) of binding to the "d"-substituted peptide, (TRI L12C, pK(a2) = 12.0) compared with the "a"-substituted peptide, (TRI L16C, pK (a2) = 12.6), the reverse of the order seen for Hg(II) and Cd(II). Pb(II) also showed a stronger binding affinity for TRI L12C (K(bind) = 3.2 x 10(7) M(-1)) compared with that with TRI L16C (K(bind) = 1.2 x 10(7) M(-1)) at pH > 8.

  15. NSLS-II: Nonlinear Model Calibration for Synchrotrons

    SciTech Connect

    Bengtsson, J.

    2010-10-08

    This tech note is essentially a summary of a lecture we delivered to the Acc. Phys. Journal Club Apr, 2010. However, since the estimated accuracy of these methods has been naive and misleading in the field of particle accelerators, i.e., ignores the impact of noise, we will elaborate on this in some detail. A prerequisite for a calibration of the nonlinear Hamiltonian is that the quadratic part has been understood, i.e., that the linear optics for the real accelerator has been calibrated. For synchrotron light source operations, this problem has been solved by the interactive LOCO technique/tool (Linear Optics from Closed Orbits). Before that, in the context of hadron accelerators, it has been done by signal processing of turn-by-turn BPM data. We have outlined how to make a basic calibration of the nonlinear model for synchrotrons. In particular, we have shown how this was done for LEAR, CERN (antiprotons) in the mid-80s. Specifically, our accuracy for frequency estimation was {approx} 1 x 10{sup -5} for 1024 turns (to calibrate the linear optics) and {approx} 1 x 10{sup -4} for 256 turns for tune footprint and betatron spectrum. For a comparison, the estimated tune footprint for stable beam for NSLS-II is {approx}0.1. Since the transverse damping time is {approx}20 msec, i.e., {approx}4,000 turns. There is no fundamental difference for: antiprotons, protons, and electrons in this case. Because the estimated accuracy for these methods in the field of particle accelerators has been naive, i.e., ignoring the impact of noise, we have also derived explicit formula, from first principles, for a quantitative statement. For e.g. N = 256 and 5% noise we obtain {delta}{nu} {approx} 1 x 10{sup -5}. A comparison with the state-of-the-arts in e.g. telecomm and electrical engineering since the 60s is quite revealing. For example, Kalman filter (1960), crucial for the: Ranger, Mariner, and Apollo (including the Lunar Module) missions during the 60s. Or Claude Shannon et al

  16. Student Instructor Load Model-Phase II (SIL-II). Summary Description.

    ERIC Educational Resources Information Center

    Bowen, Brent L.; And Others

    The report describes the Army Individual Training Establishment and the model designed to simulate the training given by the 11 Army Training Centers and by the 54 Army Service Schools in terms of students/trainees and the instructor/trainer and overhead staffing and costs required to support the training requirements. The model accepts…

  17. A Feasibility Study on the Model Elementary Teacher Education Program, Phase II; Vol. II. Final Report.

    ERIC Educational Resources Information Center

    Massachusetts Univ., Amherst.

    The second volume of the study contains the sections on management feasibility and economic feasibility, which comprise more than two-thirds of the document, and sections on simulation modeling, client acceptability, inservice design, evaluation, and maintaining relevance of the model for teacher education in the 1970's. The section on management…

  18. Alternative Models of Service, Centralized Machine Operations. Phase II Report. Volume II.

    ERIC Educational Resources Information Center

    Technology Management Corp., Alexandria, VA.

    A study was conducted to determine if the centralization of playback machine operations for the national free library program would be feasible, economical, and desirable. An alternative model of playback machine services was constructed and compared with existing network operations considering both cost and service. The alternative model was…

  19. Astronaut Bruce McCandless II modeling NASA manned maneuvering unit (MMU)

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Astronaut Bruce McCandless II modeling NASA's manned maneuvering unit (MMU) in the Johnson Space Center's laboratory support facility bldg 34. He is posed against a dark background to give the illusion of space flight.

  20. Astronaut Bruce McCandless II modeling NASA manned maneuvering unit (MMU)

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Side view of Astronaut Bruce McCandless II modeling NASA's manned maneuvering unit (MMU) in the Johnson Space Center's laboratory support facility bldg 34. He is posed against a dark background to give the illusion of space flight.

  1. Analysis of the photosystem II by modelling the fluorescence yield transients during 10 seconds after a 10 ns pulse

    NASA Astrophysics Data System (ADS)

    Belyaeva, Natalya E.; Schmitt, Franz-Josef; Paschenko, Vladimir Z.; Riznichenko, Galina Yu.; Rubin, Andrew B.

    2014-10-01

    The dynamics of the photosystem II (PS II) redox states is imitated over nine orders of magnitude in time. Our simulations focus on the information of the chlorophyll a fluorescence induced by a 10 ns laser flash. The PS II model analyzes differences in the PS II reaction between leaves (A. Thaliana, spinach) and thermophilic Chlorella cells.

  2. A Linear Stochastic Dynamical Model of ENSO. Part II: Analysis.

    NASA Astrophysics Data System (ADS)

    Thompson, C. J.; Battisti, D. S.

    2001-02-01

    In this study the behavior of a linear, intermediate model of ENSO is examined under stochastic forcing. The model was developed in a companion paper (Part I) and is derived from the Zebiak-Cane ENSO model. Four variants of the model are used whose stabilities range from slightly damped to moderately damped. Each model is run as a simulation while being perturbed by noise that is uncorrelated (white) in space and time. The statistics of the model output show the moderately damped models to be more realistic than the slightly damped models. The moderately damped models have power spectra that are quantitatively quite similar to observations, and a seasonal pattern of variance that is qualitatively similar to observations. All models produce ENSOs that are phase locked to the annual cycle, and all display the `spring barrier' characteristic in their autocorrelation patterns, though in the models this `barrier' occurs during the summer and is less intense than in the observations (inclusion of nonlinear effects is shown to partially remedy this deficiency). The more realistic models also show a decadal variability in the lagged autocorrelation pattern that is qualitatively similar to observations.Analysis of the models shows that the greatest part of the variability comes from perturbations that project onto the first singular vector, which then grow rapidly into the ENSO mode. Essentially, the model output represents many instances of the ENSO mode, with random phase and amplitude, stimulated by the noise through the optimal transient growth of the singular vectors.The limit of predictability for each model is calculated and it is shown that the more realistic (moderately damped) models have worse potential predictability (9-15 months) than the deterministic chaotic models that have been studied widely in the literature. The predictability limits are strongly correlated with the stability of the models' ENSO mode-the more highly damped models having much shorter

  3. Available for the Apple II: FIRM: Florida InteRactive Modeler.

    ERIC Educational Resources Information Center

    Levy, C. Michael; And Others

    1983-01-01

    The Apple II microcomputer program described allows instructors with minimal programing experience to construct computer models of psychological phenomena for students to investigate. Use of these models eliminates need to maintain/house/breed animals or purchase sophisticated laboratory equipment. Several content models are also described,…

  4. A model for the separation of cloud and aerosol in SAGE II occultation data

    NASA Technical Reports Server (NTRS)

    Kent, G. S.; Winker, D. M.; Osborn, M. T.; Skeens, K. M.

    1993-01-01

    The Stratospheric Aerosol and Gas Experiment (SAGE) II satellite experiment measures the extinction due to aerosols and thin cloud, at wavelengths of 0.525 and 1.02 micrometers, down to an altitude of 6 km. The wavelength dependence of the extinction due to aerosols differs from that of the extinction due to cloud and is used as the basis of a model for separating these two components. The model is presented and its validation using airborne lidar data, obtained coincident with SAGE II observations, is described. This comparison shows that smaller SAGE II cloud extinction values correspond to the presence of subvisible cirrus cloud in the lidar record. Examples of aerosol and cloud data products obtained using this model to interpret SAGE II upper tropospheric and lower stratospheric data are also shown.

  5. Stably transfected adherent cancer cell models with decreased expression of 5'-nucleotidase cN-II.

    PubMed

    Bricard, Gabriel; Cros-Perrial, Emeline; Machon, Christelle; Dumontet, Charles; Jordheim, Lars Petter

    2016-12-01

    The 5'-nucleotidase cN-II has been shown to be associated with the sensitivity to nucleoside analogues, the survival of cytarabine treated leukemia patients and to cell proliferation. Due to the lack of relevant cell models for solid tumors, we developed four cell lines with low cN-II expression and characterized them concerning their in vitro sensitivity to cancer drugs and their intracellular nucleotide pools. All four cell models had an important decrease of cN-II expression but did not show modified sensitivity, cell proliferation or nucleotide pools. Our cell models will be important for the study of the role of cN-II in human cancer cells.

  6. A model for the separation of cloud and aerosol in SAGE II occultation data

    NASA Technical Reports Server (NTRS)

    Kent, G. S.; Winker, D. M.; Osborn, M. T.; Skeens, K. M.

    1993-01-01

    The Stratospheric Aerosol and Gas Experiment (SAGE) II satellite experiment measures the extinction due to aerosols and thin cloud, at wavelengths of 0.525 and 1.02 micrometers, down to an altitude of 6 km. The wavelength dependence of the extinction due to aerosols differs from that of the extinction due to cloud and is used as the basis of a model for separating these two components. The model is presented and its validation using airborne lidar data, obtained coincident with SAGE II observations, is described. This comparison shows that smaller SAGE II cloud extinction values correspond to the presence of subvisible cirrus cloud in the lidar record. Examples of aerosol and cloud data products obtained using this model to interpret SAGE II upper tropospheric and lower stratospheric data are also shown.

  7. Multidimensional realistic modelling of Cepheid-like variables - II. Analysis of a Cepheid model

    NASA Astrophysics Data System (ADS)

    Mundprecht, Eva; Muthsam, Herbert J.; Kupka, Friedrich

    2015-05-01

    Non-local, time-dependent convection models have been used to explain the location of double-mode pulsations in Cepheids in the HR diagram as well as the existence and location of the red edge of the instability strip. These properties are highly sensitive to model parameters. We use 2D radiation-hydrodynamical simulations with realistic microphysics and grey radiative transfer to model a short-period Cepheid. The simulations show that the strength of the convection zone varies significantly over the pulsation period and exhibits a phase shift relative to the variations in radius. We evaluate the convective flux and the work integral as predicted by the most common convection models. It turns out that over one pulsation cycle the model parameter αc, has to be varied by up to a factor of beyond 2 to match the convective flux obtained from the simulations. To bring convective fluxes integrated over the He II convection zone and the overshoot zone below into agreement, this parameter has to be varied by a factor of up to ˜7.5 (Kuhfuß). We then present results on the energetics of the convection and overshoot zone by radially symmetric and fluctuating quantities. To successfully model this scenario by a static, 1D or even by a simple time-dependent model appears extremely challenging. We conclude that significant improvements are needed to make predictions based on 1D models more robust and to improve the reliability of conclusions on the convection-pulsation coupling drawn from them. Multidimensional simulations can provide guidelines for developing descriptions of convection then applied in traditional 1D modelling.

  8. SCIENTIFIC UNCERTAINTIES IN ATMOSPHERIC MERCURY MODELS III: BOUNDARY AND INITIAL CONDITIONS, MODEL GRID RESOLUTION, AND HG(II) REDUCTION MECHANISMS

    EPA Science Inventory

    In this study we investigate the CMAQ model response in terms of simulated mercury concentration and deposition to boundary/initial conditions (BC/IC), model grid resolution (12- versus 36-km), and two alternative Hg(II) reduction mechanisms. The model response to the change of g...

  9. SCIENTIFIC UNCERTAINTIES IN ATMOSPHERIC MERCURY MODELS III: BOUNDARY AND INITIAL CONDITIONS, MODEL GRID RESOLUTION, AND HG(II) REDUCTION MECHANISMS

    EPA Science Inventory

    In this study we investigate the CMAQ model response in terms of simulated mercury concentration and deposition to boundary/initial conditions (BC/IC), model grid resolution (12- versus 36-km), and two alternative Hg(II) reduction mechanisms. The model response to the change of g...

  10. Models and the dynamics of theory-building in physics. Part II-Case studies

    NASA Astrophysics Data System (ADS)

    Emch, Gérard G.

    In Part I, it was argued that models are best explained by considering the strategies from which they issue. A distinction was proposed between two classes of modeling that contribute to theory-building: H-modeling and L-modeling. Case studies are presented in this Part II to illustrate the characteristic features of these modeling strategies; examples are drawn from classical statistical mechanics and quantum physics.

  11. Standard model Higgs boson searches at CDF in Run II

    SciTech Connect

    Chuang, Shan-Huei; /Wisconsin U., Madison

    2004-10-01

    The SM Higgs boson has been searched in two channels: (1) q{bar q} {yields} WH {yields} {ell}{nu}b{bar b} for Higgs masses 110 < M{sub H} < 150 GeV and (2) gg {yields} H {yields} WW {yields} {ell}{nu}{ell}{nu} for 140 M{sub H} < 180 GeV, where {ell} {element_of} {l_brace}e,{mu}{r_brace}, using about 200 pb{sup -1} CDF Run II data. 95% C.L. limits on each Higgs production at Tevatron at {radical}s = 1.96 TeV were set as a function of Higgs mass by fitting the distribution of dijet mass (1) and dilepton azimuthal angular separation (2). They have significantly advanced the sensitivity to the SM Higgs boson cf. Run I.

  12. Low-order dynamic modeling of the Experimental Breeder Reactor II

    SciTech Connect

    Berkan, R.C. . Dept. of Nuclear Engineering); Upadhyaya, B.R.; Kisner, R.A. )

    1990-07-01

    This report describes the development of a low-order, linear model of the Experimental Breeder Reactor II (EBR-II), including the primary system, intermediate heat exchanger, and steam generator subsystems. The linear model is developed to represent full-power steady state dynamics for low-level perturbations. Transient simulations are performed using model building and simulation capabilities of the computer software Matrix{sub x}. The inherently safe characteristics of the EBR-II are verified through the simulation studies. The results presented in this report also indicate an agreement between the linear model and the actual dynamics of the plant for several transients. Such models play a major role in the learning and in the improvement of nuclear reactor dynamics for control and signal validation studies. This research and development is sponsored by the Advanced Controls Program in the Instrumentation and Controls Division of the Oak Ridge National Laboratory. 17 refs., 67 figs., 15 tabs.

  13. Two-Higgs-doublet model of type II confronted with the LHC run I and run II data

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Zhang, Feng; Han, Xiao-Fang

    2017-06-01

    We examine the parameter space of the two-Higgs-doublet model of type II after imposing the relevant theoretical and experimental constraints from the precision electroweak data, B -meson decays, and the LHC run I and run II data. We find that the searches for Higgs bosons via the τ+τ- , W W , Z Z , γ γ , h h , h Z , H Z , and A Z channels can give strong constraints on the C P -odd Higgs A and heavy C P -even Higgs H , and the parameter space excluded by each channel is respectively carved out in detail assuming that either mA or mH are fixed to 600 or 700 GeV in the scans. The surviving samples are discussed in two different regions. (i) In the standard model-like coupling region of the 125 GeV Higgs, mA is allowed to be as low as 350 GeV, and a strong upper limit is imposed on tan β . mH is allowed to be as low as 200 GeV for the appropriate values of tan β , sin (β -α ), and mA, but is required to be larger than 300 GeV for mA=700 GeV . (ii) In the wrong-sign Yukawa coupling region of the 125 GeV Higgs, the b b ¯→A /H →τ+τ- channel can impose the upper limits on tan β and sin (β -α ), and the A →h Z channel can give the lower limits on tan β and sin (β -α ). mA and mH are allowed to be as low as 60 and 200 GeV, respectively, but 320 GeV

  14. Design, development, and application of LANDIS-II, a spatial landscape simulation model with flexible temporal and spatial resolution

    Treesearch

    Robert M. Scheller; James B. Domingo; Brian R. Sturtevant; Jeremy S. Williams; Arnold Rudy; Eric J. Gustafson; David J. Mladenoff

    2007-01-01

    We introduce LANDIS-II, a landscape model designed to simulate forest succession and disturbances. LANDIS-II builds upon and preserves the functionality of previous LANDIS forest landscape simulation models. LANDIS-II is distinguished by the inclusion of variable time steps for different ecological processes; our use of a rigorous development and testing process used...

  15. Models of cuspy triaxial stellar systems - II. Regular orbits

    NASA Astrophysics Data System (ADS)

    Muzzio, J. C.; Navone, H. D.; Zorzi, A. F.

    2013-02-01

    In the first paper of this series we used the N-body method to build a dozen cuspy (γ ≃ 1) triaxial models of stellar systems, and we showed that they were highly stable over time intervals of the order of a Hubble time, even though they had very large fractions of chaotic orbits (more than 85 per cent in some cases). The models were grouped in four sets, each one comprising models morphologically resembling E2, E3, E4 and E5 galaxies, respectively. The three models within each set, although different, had the same global properties and were statistically equivalent. In the present paper we use frequency analysis to classify the regular orbits of those models. The bulk of those orbits are short-axis tubes, with a significant fraction of long-axis tubes (LATs) in the E2 models that decreases in the E3 and E4 models to become negligibly small in the E5 models. Most of the LATs in the E2 and E3 models are outer LATs, but the situation reverses in the E4 and E5 models where the few LATs are mainly inner LATs. As could be expected for cuspy models, most of the boxes are resonant orbits, i.e. boxlets. Nevertheless, only the (x, y) fishes of models E3 and E4 amount to about 10 per cent of the regular orbits, with most of the fractions of the other boxlets being of the order of 1 per cent or less.

  16. Simple inflationary quintessential model. II. Power law potentials

    NASA Astrophysics Data System (ADS)

    de Haro, Jaume; Amorós, Jaume; Pan, Supriya

    2016-09-01

    The present work is a sequel of our previous work [Phys. Rev. D 93, 084018 (2016)] which depicted a simple version of an inflationary quintessential model whose inflationary stage was described by a Higgs-type potential and the quintessential phase was responsible due to an exponential potential. Additionally, the model predicted a nonsingular universe in past which was geodesically past incomplete. Further, it was also found that the model is in agreement with the Planck 2013 data when running is allowed. But, this model provides a theoretical value of the running which is far smaller than the central value of the best fit in ns , r , αs≡d ns/d l n k parameter space where ns, r , αs respectively denote the spectral index, tensor-to-scalar ratio and the running of the spectral index associated with any inflationary model, and consequently to analyze the viability of the model one has to focus in the two-dimensional marginalized confidence level in the allowed domain of the plane (ns,r ) without taking into account the running. Unfortunately, such analysis shows that this model does not pass this test. However, in this sequel we propose a family of models runs by a single parameter α ∈[0 ,1 ] which proposes another "inflationary quintessential model" where the inflation and the quintessence regimes are respectively described by a power law potential and a cosmological constant. The model is also nonsingular although geodesically past incomplete as in the cited model. Moreover, the present one is found to be more simple compared to the previous model and it is in excellent agreement with the observational data. In fact, we note that, unlike the previous model, a large number of the models of this family with α ∈[0 ,1/2 ) match with both Planck 2013 and Planck 2015 data without allowing the running. Thus, the properties in the current family of models compared to its past companion justify its need for a better cosmological model with the successive

  17. Surface complexation modeling calculation of Pb(II) adsorption onto the calcined diatomite

    NASA Astrophysics Data System (ADS)

    Ma, Shu-Cui; Zhang, Ji-Lin; Sun, De-Hui; Liu, Gui-Xia

    2015-12-01

    Removal of noxious heavy metal ions (e.g. Pb(II)) by surface adsorption of minerals (e.g. diatomite) is an important means in the environmental aqueous pollution control. Thus, it is very essential to understand the surface adsorptive behavior and mechanism. In this work, the Pb(II) apparent surface complexation reaction equilibrium constants on the calcined diatomite and distributions of Pb(II) surface species were investigated through modeling calculations of Pb(II) based on diffuse double layer model (DLM) with three amphoteric sites. Batch experiments were used to study the adsorption of Pb(II) onto the calcined diatomite as a function of pH (3.0-7.0) and different ionic strengths (0.05 and 0.1 mol L-1 NaCl) under ambient atmosphere. Adsorption of Pb(II) can be well described by Freundlich isotherm models. The apparent surface complexation equilibrium constants (log K) were obtained by fitting the batch experimental data using the PEST 13.0 together with PHREEQC 3.1.2 codes and there is good agreement between measured and predicted data. Distribution of Pb(II) surface species on the diatomite calculated by PHREEQC 3.1.2 program indicates that the impurity cations (e.g. Al3+, Fe3+, etc.) in the diatomite play a leading role in the Pb(II) adsorption and dominant formation of complexes and additional electrostatic interaction are the main adsorption mechanism of Pb(II) on the diatomite under weak acidic conditions.

  18. Review: Lessons from in vitro studies and a related intracellular angiotensin II transgenic mouse model

    PubMed Central

    Re, Richard N.

    2012-01-01

    In the classical renin-angiotensin system, circulating ANG II mediates growth stimulatory and hemodynamic effects through the plasma membrane ANG II type I receptor, AT1. ANG II also exists in the intracellular space in some native cells, and tissues and can be upregulated in diseases, including hypertension and diabetes. Moreover, intracellular AT1 receptors can be found associated with endosomes, nuclei, and mitochondria. Intracellular ANG II can function in a canonical fashion through the native receptor and also in a noncanonical fashion through interaction with alternative proteins. Likewise, the receptor and proteolytic fragments of the receptor can function independently of ANG II. Participation of the receptor and ligand in alternative intracellular pathways may serve to amplify events that are initiated at the plasma membrane. We review historical and current literature relevant to ANG II, compared with other intracrines, in tissue culture and transgenic models. In particular, we describe a new transgenic mouse model, which demonstrates that intracellular ANG II is linked to high blood pressure. Appreciation of the diverse, pleiotropic intracellular effects of components of the renin-angiotensin system should lead to alternative disease treatment targets and new therapies. PMID:22170617

  19. Altered Chondrocyte Differentiation and Extracellular Matrix Homeostasis in a Zebrafish Model for Mucolipidosis II

    PubMed Central

    Flanagan-Steet, Heather; Sias, Christina; Steet, Richard

    2009-01-01

    Mucolipidosis II (ML-II) is a pediatric disorder caused by defects in the biosynthesis of mannose 6-phosphate, the carbohydrate recognition signal responsible for targeting certain acid hydrolases to lysosomes. The mechanisms underlying the developmental defects of ML-II are largely unknown due in part to the lack of suitable animal models. To overcome these limitations, we developed a model for ML-II in zebrafish by inhibiting the expression of N-acetylglucosamine-1-phosphotransferase, the enzyme that initiates mannose 6-phosphate biosynthesis. Morphant embryos manifest craniofacial defects, impaired motility, and abnormal otolith and pectoral fin development. Decreased mannose phosphorylation of several lysosomal glycosidases was observed in morphant lysates, consistent with the reduction in phosphotransferase activity. Investigation of the craniofacial defects in the morphants uncovered striking changes in the timing and localization of both type II collagen and Sox9 expression, suggestive of an accelerated chondrocyte differentiation program. Accumulation of type II collagen was also noted within misshapen cartilage elements at later stages of development. Furthermore, we observed abnormal matrix formation and calcium deposition in morphant otoliths. Collectively, these data provide new insight into the developmental pathology of ML-II and suggest that altered production and/or homeostasis of extracellular matrix proteins are integral to the disease process. These findings highlight the potential of the zebrafish system in studying lysosomal disease pathogenesis. PMID:19834066

  20. Multiscale geometric modeling of macromolecules II: Lagrangian representation

    PubMed Central

    Feng, Xin; Xia, Kelin; Chen, Zhan; Tong, Yiying; Wei, Guo-Wei

    2013-01-01

    Geometric modeling of biomolecules plays an essential role in the conceptualization of biolmolecular structure, function, dynamics and transport. Qualitatively, geometric modeling offers a basis for molecular visualization, which is crucial for the understanding of molecular structure and interactions. Quantitatively, geometric modeling bridges the gap between molecular information, such as that from X-ray, NMR and cryo-EM, and theoretical/mathematical models, such as molecular dynamics, the Poisson-Boltzmann equation and the Nernst-Planck equation. In this work, we present a family of variational multiscale geometric models for macromolecular systems. Our models are able to combine multiresolution geometric modeling with multiscale electrostatic modeling in a unified variational framework. We discuss a suite of techniques for molecular surface generation, molecular surface meshing, molecular volumetric meshing, and the estimation of Hadwiger’s functionals. Emphasis is given to the multiresolution representations of biomolecules and the associated multiscale electrostatic analyses as well as multiresolution curvature characterizations. The resulting fine resolution representations of a biomolecular system enable the detailed analysis of solvent-solute interaction, and ion channel dynamics, while our coarse resolution representations highlight the compatibility of protein-ligand bindings and possibility of protein-protein interactions. PMID:23813599

  1. Rhode Island Model Evaluation & Support System: Support Professional. Edition II

    ERIC Educational Resources Information Center

    Rhode Island Department of Education, 2015

    2015-01-01

    Rhode Island educators believe that implementing a fair, accurate, and meaningful evaluation and support system for support professionals will help improve student outcomes. The primary purpose of the Rhode Island Model Support Professional Evaluation and Support System (Rhode Island Model) is to help all support professionals do their best work…

  2. LP II--A GOAL PROGRAMMING MODEL FOR MEDIA.

    ERIC Educational Resources Information Center

    CHARNES, A.; AND OTHERS

    A GOAL PROGRAMING MODEL FOR SELECTING MEDIA IS PRESENTED WHICH ALTERS THE OBJECTIVE AND EXTENDS PREVIOUS MEDIA MODELS BY ACCOUNTING FOR CUMULATIVE DUPLICATING AUDIENCES OVER A VARIETY OF TIME PERIODS. THIS PERMITS DETAILED CONTROL OF THE DISTRIBUTION OF MESSAGE FREQUENCIES DIRECTED AT EACH OF NUMEROUS MARKETING TARGETS OVER A SEQUENCE OF…

  3. A Primary Prevention Program: Teaching Models I and II.

    ERIC Educational Resources Information Center

    Harlan, Nancy T; Tschiderer, Patricia A.

    Two teaching models of a service delivery program designed to prevent speech-language problems in lower socioeconomic children were compared. Specific goals included increasing mothers' awareness of the sensory input to which infants are responsive and increasing mothers' abilities to read infant nonverbal signals. In Model 1, two speech-language…

  4. [Application of multilevel models in the evaluation of bioequivalence (II).].

    PubMed

    Liu, Qiao-lan; Shen, Zhuo-zhi; Li, Xiao-song; Chen, Feng; Yang, Min

    2010-03-01

    The main purpose of this paper is to explore the applicability of multivariate multilevel models for bioequivalence evaluation. Using an example of a 4 x 4 cross-over test design in evaluating bioequivalence of homemade and imported rosiglitazone maleate tablets, this paper illustrated the multivariate-model-based method for partitioning total variances of ln(AUC) and ln(C(max)) in the framework of multilevel models. It examined the feasibility of multivariate multilevel models in directly evaluating average bioequivalence (ABE), population bioequivalence (PBE) and individual bioequivalence (IBE). Taking into account the correlation between ln(AUC) and ln(C(max)) of rosiglitazone maleate tablets, the proposed models suggested no statistical difference between the two effect measures in their ABE bioequivalence via joint tests, whilst a contradictive conclusion was derived based on univariate multilevel models. Furthermore, the PBE and IBE for both ln(AUC) and ln(C(max)) of the two types of tablets were assessed with no statistical difference based on estimates of variance components from the proposed models. Multivariate multilevel models could be used to analyze bioequivalence of multiple effect measures simultaneously and they provided a new way of statistical analysis to evaluate bioequivalence.

  5. [Collaboration among health professionals (II). Usefulness of a model].

    PubMed

    D'Amour, Danielle; San Martín Rodríguez, Leticia

    2006-09-01

    This second article provides a model which helps one to better understand the process of collaboration by interprofessional teams and makes it possible to evaluate the quality of the aforementioned collaboration. To this end, the authors first present a structural model of inter-professional collaboration followed by a typology of collaboration which is derived from the functionality of said model. This model is composed by four interrelated dimensions; the functionality of these has given rise to a typology of collaboration at three intensities: in action, in construction and collaboration during inertia. The model and the typology constitute a useful tool for managers and for health professionals since they help to better understand, manage and develop collaboration among the distinct professionals inside of the same organization as among those who belong to distinct organizations.

  6. Filament winding cylinders. II - Validation of the process model

    NASA Technical Reports Server (NTRS)

    Calius, Emilio P.; Lee, Soo-Yong; Springer, George S.

    1990-01-01

    Analytical and experimental studies were performed to validate the model developed by Lee and Springer for simulating the manufacturing process of filament wound composite cylinders. First, results calculated by the Lee-Springer model were compared to results of the Calius-Springer thin cylinder model. Second, temperatures and strains calculated by the Lee-Springer model were compared to data. The data used in these comparisons were generated during the course of this investigation with cylinders made of Hercules IM-6G/HBRF-55 and Fiberite T-300/976 graphite-epoxy tows. Good agreement was found between the calculated and measured stresses and strains, indicating that the model is a useful representation of the winding and curing processes.

  7. Filament winding cylinders. II - Validation of the process model

    NASA Technical Reports Server (NTRS)

    Calius, Emilio P.; Lee, Soo-Yong; Springer, George S.

    1990-01-01

    Analytical and experimental studies were performed to validate the model developed by Lee and Springer for simulating the manufacturing process of filament wound composite cylinders. First, results calculated by the Lee-Springer model were compared to results of the Calius-Springer thin cylinder model. Second, temperatures and strains calculated by the Lee-Springer model were compared to data. The data used in these comparisons were generated during the course of this investigation with cylinders made of Hercules IM-6G/HBRF-55 and Fiberite T-300/976 graphite-epoxy tows. Good agreement was found between the calculated and measured stresses and strains, indicating that the model is a useful representation of the winding and curing processes.

  8. Mathematical modeling of Fe(II), Cu(II), Ni(II) and Zn(II) removal in a horizontal rotating tubular bioreactor.

    PubMed

    Rezić, Tonči; Zeiner, Michaela; Santek, Božidar; Novak, Srđan

    2011-11-01

    Industrial wastewaters polluted with toxic heavy metals are serious ecological and environmental problem. Therefore, in this study multi-heavy metals (Fe(2+), Cu(2+), Ni(2+) and Zn(2+)) removal process with mixed microbial culture was examined in the horizontal rotating tubular bioreactor (HRTB) by different combinations of process parameters. Hydrodynamic conditions and biomass sorption capacity have main impact on the removal efficiency of heavy metals: Fe(2+) 95.5-79.0%, Ni(2+) 92.7-54.8%, Cu(2+) 87.7-54.9% and Zn(2+) 81.8-38.1%, respectively. On the basis of experimental results, integral mathematical model of removal heavy metals in the HRTB was established. It combines hydrodynamics (mixing), mass transfer and kinetics to define bioprocess conduction in the HRTB. Mixing in the HRTB was described by structured cascade model and metal ion removal by two combined diffusion-adsorption models, respectively. For Langmuir model, average variances between experimental and simulated concentrations of metal ions were in the range of 1.22-10.99 × 10(-3) and for the Freundlich model 0.12-3.98 × 10(-3), respectively. On the basis of previous facts, it is clear that developed integral bioprocess model with Freundlich model is more efficient in the prediction of concentration of metal ions in the HRTB. Furthermore, the results obtained also pointed out that the established model is at the same time accurate and robust and therefore it has great potential for use in the scale-up procedure.

  9. Conceptual Modeling in the Time of the Revolution: Part II

    NASA Astrophysics Data System (ADS)

    Mylopoulos, John

    Conceptual Modeling was a marginal research topic at the very fringes of Computer Science in the 60s and 70s, when the discipline was dominated by topics focusing on programs, systems and hardware architectures. Over the years, however, the field has moved to centre stage and has come to claim a central role both in Computer Science research and practice in diverse areas, such as Software Engineering, Databases, Information Systems, the Semantic Web, Business Process Management, Service-Oriented Computing, Multi-Agent Systems, Knowledge Management, and more. The transformation was greatly aided by the adoption of standards in modeling languages (e.g., UML), and model-based methodologies (e.g., Model-Driven Architectures) by the Object Management Group (OMG) and other standards organizations. We briefly review the history of the field over the past 40 years, focusing on the evolution of key ideas. We then note some open challenges and report on-going research, covering topics such as the representation of variability in conceptual models, capturing model intentions, and models of laws.

  10. Synthetic Model of the Oxygen-Evolving Center: Photosystem II under the Spotlight.

    PubMed

    Yu, Yang; Hu, Cheng; Liu, Xiaohong; Wang, Jiangyun

    2015-09-21

    The oxygen-evolving center (OEC) in photosystem II catalyzes a water splitting reaction. Great efforts have already been made to artificially synthesize the OEC, in order to elucidate the structure-function relationship and the mechanism of the reaction. Now, a new synthetic model makes the best mimic yet of the OEC. This recent study opens up the possibility to study the mechanism of photosystem II and photosynthesis in general for applications in renewable energy and synthetic biology.

  11. Measurement and modeling of advanced coal conversion processes, Volume II

    SciTech Connect

    Solomon, P.R.; Serio, M.A.; Hamblen, D.G.

    1993-06-01

    A two dimensional, steady-state model for describing a variety of reactive and nonreactive flows, including pulverized coal combustion and gasification, is presented. The model, referred to as 93-PCGC-2 is applicable to cylindrical, axi-symmetric systems. Turbulence is accounted for in both the fluid mechanics equations and the combustion scheme. Radiation from gases, walls, and particles is taken into account using a discrete ordinates method. The particle phase is modeled in a lagrangian framework, such that mean paths of particle groups are followed. A new coal-general devolatilization submodel (FG-DVC) with coal swelling and char reactivity submodels has been added.

  12. Identification of 14 quercetin phase II mono- and mixed conjugates and their formation by rat and human phase II in vitro model systems.

    PubMed

    van der Woude, Hester; Boersma, Marelle G; Vervoort, Jacques; Rietjens, Ivonne M C M

    2004-11-01

    In this study, the HPLC, UV-vis, LC-MS, and 1H NMR characteristics of 14 different phase II mono- and mixed conjugates of quercetin were determined, providing a useful tool in the identification of quercetin phase II metabolite patterns in various biological systems. Using these data, the phase II metabolism of quercetin by different rat and human liver and intestine in vitro models, including cell lines, S9 samples, and hepatocytes, was investigated. A comparison of quercetin phase II metabolism between rat and human liver and intestinal cell lines, S9, and hepatocytes showed considerable variation in the nature and ratios of quercetin conjugate formation. It could be established that the intestine contributes significantly to the phase II metabolism of quercetin, especially to its sulfation, that organ-dependent phase II metabolism in rat and man differ significantly, and that human interindividual variation is higher for quercetin sulfation than for glucuronidation or methylation. Furthermore, quercetin conjugation by different in vitro models from corresponding origins may differ significantly. The identification of the various mono- and mixed quercetin phase II conjugates revealed significant differences in phase II conjugation by a variety of in vitro models and led to the conclusion that none of the in vitro models converted quercetin to a phase II metabolite mixture similar to the in vivo plasma metabolite pattern of quercetin. Altogether, the identification of a wide range of phase II metabolites of quercetin as presented in this study allows the determination of quercetin phase II biotransformation patterns and opens the way for a better-funded assessment of the biological activity of quercetin in a variety of biological systems.

  13. Distributed routing rainfall-runoff model; version II

    USGS Publications Warehouse

    Alley, W.M.; Smith, P.E.

    1982-01-01

    A computer program of a watershed model for routing storm runoff through a branched system of pipes and (or) natural channels using rainfall as input is described. The model provides detailed simulation of storm-runoff periods selected by the user and a daily soil-moisture accounting between storms. A drainage basin is represented as a set of overland-flow, channel, and reservoir seqments which ,jointly describe the drainage features of the basin. Kinematic wave theory is used for routing flows over contributing overland-flow areas and through the channel network. A set of model segments can be arranged into a network that will represent many complex drainage basins. The model is intended primarily for application to urban watersheds, but may have limited applications to rural watersheds.

  14. Comprehensive computer model for magnetron sputtering. II. Charged particle transport

    SciTech Connect

    Jimenez, Francisco J. Dew, Steven K.; Field, David J.

    2014-11-01

    Discharges for magnetron sputter thin film deposition systems involve complex plasmas that are sensitively dependent on magnetic field configuration and strength, working gas species and pressure, chamber geometry, and discharge power. The authors present a numerical formulation for the general solution of these plasmas as a component of a comprehensive simulation capability for planar magnetron sputtering. This is an extensible, fully three-dimensional model supporting realistic magnetic fields and is self-consistently solvable on a desktop computer. The plasma model features a hybrid approach involving a Monte Carlo treatment of energetic electrons and ions, along with a coupled fluid model for thermalized particles. Validation against a well-known one-dimensional system is presented. Various strategies for improving numerical stability are investigated as is the sensitivity of the solution to various model and process parameters. In particular, the effect of magnetic field, argon gas pressure, and discharge power are studied.

  15. SPARTAN II: An Instructional High Resolution Land Combat Model

    DTIC Science & Technology

    1993-03-01

    and most important aspects of land combat models. Normally, terrain is represented by subdividing it into regularly shaped polygons of various sizes...separately "would be prohibitive for most force on force modelling purposes" (13:9-1). There are basically two types of projectiles : impact projectiles ...which must hit a target to cause damage, and fragmenting projectiles , which explode and cause damage either by the explosion or by fragments (13:8-1). For

  16. New hexadentate macrocyclic ligand and their copper(II) and nickel(II) complexes: Spectral, magnetic, electrochemical, thermal, molecular modeling and antimicrobial studies

    NASA Astrophysics Data System (ADS)

    Chandra, Sulekh; Ruchi; Qanungo, Kushal; Sharma, Saroj. K.

    Ni(II) and Cu(II) complexes were synthesized with a hexadentate macrocyclic ligand [3,4,8,9tetraoxo-2,5,7,10tetraaza-1,6dithio-(3,4,8,9) dipyridinedodecane(L)] and characterized by elemental analysis, molar conductance measurements, mass, NMR, IR, electronic, EPR spectral, thermal and molecular modeling studies. All the complexes are 1:2 electrolytes in nature and may be formulated as [M(L)]X2 [where, M = Ni(II) and Cu(II) and X = Cl-, NO3-, ½SO42-, CH3COO-]. On the basis of IR, electronic and EPR spectral studies an octahedral geometry has been assigned for Ni(II) complexes and tetragonal geometry for Cu(II) complexes. The antimicrobial activities and LD50 values of the ligand and its complexes, as growth inhibiting agents, have been screened in vitro against two different species of bacteria and plant pathogenic fungi.

  17. A physical model for the [C ii]-FIR deficit in luminous galaxies

    NASA Astrophysics Data System (ADS)

    Narayanan, Desika; Krumholz, Mark R.

    2017-05-01

    Observations of ionized carbon at 158 μm ([C ii]) from luminous star-forming galaxies at z ˜ 0 show that their ratios of [C ii] to far-infrared (FIR) luminosity are systematically lower than those of more modestly star-forming galaxies. In this paper, we provide a theory for the origin of this so-called [C ii] deficit in galaxies. Our model treats the interstellar medium as a collection of clouds with radially stratified chemical and thermal properties, which are dictated by the clouds' volume and surface densities, as well as the interstellar radiation and cosmic ray fields to which they are exposed. [C ii] emission arises from the outer, H i-dominated layers of clouds, and from regions where the hydrogen is H2 but the carbon is predominantly C+. In contrast, the most shielded regions of clouds are dominated by CO, and produce little [C ii] emission. This provides a natural mechanism to explain the observed [C ii]-star formation relation: galaxies' star formation rates are largely driven by the surface densities of their clouds. As this rises, so does the fraction of gas in the CO-dominated phase that produces little [C ii] emission. Our model further suggests that the apparent offset in the [C ii]-FIR relation for high-z sources compared to those at present epoch may arise from systematically larger gas masses at early times: a galaxy with a large gas mass can sustain a high star formation rate even with a relatively modest surface density, allowing copious [C ii] emission to coexist with rapid star formation.

  18. The Clinical Teacher for Special Education. Final Report: Volume II; Evaluating the Model.

    ERIC Educational Resources Information Center

    Schwartz, Louis; Oseroff, Andrew

    Effectiveness of the clinical teaching model (CTM) developed at Florida State University is documented in Volume II of the project's final report. Reviewed is literature related to teacher effectiveness and conceptual changes, conceptual models and instructional systems, and evaluation research in education. Research design and procedures are…

  19. The Clinical Teacher for Special Education. Final Report: Volume II; Evaluating the Model.

    ERIC Educational Resources Information Center

    Schwartz, Louis; Oseroff, Andrew

    Effectiveness of the clinical teaching model (CTM) developed at Florida State University is documented in Volume II of the project's final report. Reviewed is literature related to teacher effectiveness and conceptual changes, conceptual models and instructional systems, and evaluation research in education. Research design and procedures are…

  20. A Feasibility Study on the Model Elementary Teacher Education Program. Phase II, Vol. I. Final Report.

    ERIC Educational Resources Information Center

    Massachusetts Univ., Amherst.

    The first volume of the study contains a 25-page overview of the complete feasibility study (Phase II), including sections on pedagogical feasibility, management feasibility, economic feasibility, simulation modeling, client acceptability, inservice design, evaluation and research, and maintaining relevance of the model for teacher education in…

  1. Model for the generation of leptonic mass. II

    SciTech Connect

    Fryberger, D.

    1981-08-15

    An analysis of a model for the generation of leptonic mass that considered only symmetric solutions is extended to include the possibility of asymmetric solutions. This possibility arises from a breakdown of a permutation symmetry between muon and electron. This broken symmetry also furnishes in a natural way a quantum number which distinguishes muons from electrons. A numerical study of the solutions of the extended model is performed, and it is shown that indeed their structure has a region with asymmetric solutions. The observed ..mu..-e mass ratio lies within the range of estimates using this model, but the mass-splitting estimates thus obtained are seen to be very sensitive to computational errors as well as assumptions about unknown non-QED physics. The reasons for this sensitivity and sources of these errors are discussed. By an extrapolation of the model beyond the tau, a new yet heavier lepton is predicted, and a comparison is made to those predicted by some other models. Experimental tests of these predictions shoud be possible using coming generations of accelerators.

  2. GSTARS computer models and their applications, Part II: Applications

    USGS Publications Warehouse

    Simoes, F.J.M.; Yang, C.T.

    2008-01-01

    In part 1 of this two-paper series, a brief summary of the basic concepts and theories used in developing the Generalized Stream Tube model for Alluvial River Simulation (GSTARS) computer models was presented. Part 2 provides examples that illustrate some of the capabilities of the GSTARS models and how they can be applied to solve a wide range of river and reservoir sedimentation problems. Laboratory and field case studies are used and the examples show representative applications of the earlier and of the more recent versions of GSTARS. Some of the more recent capabilities implemented in GSTARS3, one of the latest versions of the series, are also discussed here with more detail. ?? 2008 International Research and Training Centre on Erosion and Sedimentation and the World Association for Sedimentation and Erosion Research.

  3. Bayesian analysis. II. Signal detection and model selection

    NASA Astrophysics Data System (ADS)

    Bretthorst, G. Larry

    In the preceding. paper, Bayesian analysis was applied to the parameter estimation problem, given quadrature NMR data. Here Bayesian analysis is extended to the problem of selecting the model which is most probable in view of the data and all the prior information. In addition to the analytic calculation, two examples are given. The first example demonstrates how to use Bayesian probability theory to detect small signals in noise. The second example uses Bayesian probability theory to compute the probability of the number of decaying exponentials in simulated T1 data. The Bayesian answer to this question is essentially a microcosm of the scientific method and a quantitative statement of Ockham's razor: theorize about possible models, compare these to experiment, and select the simplest model that "best" fits the data.

  4. Spatial Moran models, II: cancer initiation in spatially structured tissue

    PubMed Central

    Foo, J; Leder, K

    2016-01-01

    We study the accumulation and spread of advantageous mutations in a spatial stochastic model of cancer initiation on a lattice. The parameters of this general model can be tuned to study a variety of cancer types and genetic progression pathways. This investigation contributes to an understanding of how the selective advantage of cancer cells together with the rates of mutations driving cancer, impact the process and timing of carcinogenesis. These results can be used to give insights into tumor heterogeneity and the “cancer field effect,” the observation that a malignancy is often surrounded by cells that have undergone premalignant transformation. PMID:26126947

  5. Modeling an electro-photographic printer, part II: color systems

    NASA Astrophysics Data System (ADS)

    Kriss, Michael A.

    2007-01-01

    This paper will outline a simplified model for the development of toner dots on a reflective support in a color electro-photographic system. A model developed for a monochrome system will be adapted to a color imaging system where four pigments, each capable of scatting light, is used to form a digital halftone image. The combination of physical and optical dot gains, interlayer scattering, on-dot and off-dot digital halftones will be explored and the results demonstrated in terms color shifts due to layer order and dot gain due to halftone geometry.

  6. Simulation of reactive nanolaminates using reduced models: II. Normal propagation

    SciTech Connect

    Salloum, Maher; Knio, Omar M.

    2010-03-15

    Transient normal flame propagation in reactive Ni/Al multilayers is analyzed computationally. Two approaches are implemented, based on generalization of earlier methodology developed for axial propagation, and on extension of the model reduction formalism introduced in Part I. In both cases, the formulation accommodates non-uniform layering as well as the presence of inert layers. The equations of motion for the reactive system are integrated using a specially-tailored integration scheme, that combines extended-stability, Runge-Kutta-Chebychev (RKC) integration of diffusion terms with exact treatment of the chemical source term. The detailed and reduced models are first applied to the analysis of self-propagating fronts in uniformly-layered materials. Results indicate that both the front velocities and the ignition threshold are comparable for normal and axial propagation. Attention is then focused on analyzing the effect of a gap composed of inert material on reaction propagation. In particular, the impacts of gap width and thermal conductivity are briefly addressed. Finally, an example is considered illustrating reaction propagation in reactive composites combining regions corresponding to two bilayer widths. This setup is used to analyze the effect of the layering frequency on the velocity of the corresponding reaction fronts. In all cases considered, good agreement is observed between the predictions of the detailed model and the reduced model, which provides further support for adoption of the latter. (author)

  7. PULSATING REVERSE DETONATION MODELS OF TYPE Ia SUPERNOVAE. II. EXPLOSION

    SciTech Connect

    Bravo, Eduardo; Garcia-Senz, Domingo; Cabezon, Ruben M.; DomInguez, Inmaculada E-mail: domingo.garcia@upc.edu E-mail: inma@ugr.es

    2009-04-20

    Observational evidences point to a common explosion mechanism of Type Ia supernovae based on a delayed detonation of a white dwarf (WD). However, all attempts to find a convincing ignition mechanism based on a delayed detonation in a destabilized, expanding, white dwarf have been elusive so far. One of the possibilities that has been invoked is that an inefficient deflagration leads to pulsation of a Chandrasekhar-mass WD, followed by formation of an accretion shock that confines a carbon-oxygen rich core, while transforming the kinetic energy of the collapsing halo into thermal energy of the core, until an inward moving detonation is formed. This chain of events has been termed Pulsating Reverse Detonation (PRD). In this work, we present three-dimensional numerical simulations of PRD models from the time of detonation initiation up to homologous expansion. Different models characterized by the amount of mass burned during the deflagration phase, M {sub defl}, give explosions spanning a range of kinetic energies, K {approx} (1.0-1.2) x 10{sup 51} erg, and {sup 56}Ni masses, M({sup 56}Ni) {approx} 0.6-0.8 M {sub sun}, which are compatible with what is expected for typical Type Ia supernovae. Spectra and light curves of angle-averaged spherically symmetric versions of the PRD models are discussed. Type Ia supernova spectra pose the most stringent requirements on PRD models.

  8. Modeling Degradation in Solid Oxide Electrolysis Cells - Volume II

    SciTech Connect

    Manohar Motwani

    2011-09-01

    Idaho National Laboratory has an ongoing project to generate hydrogen from steam using solid oxide electrolysis cells (SOECs). To accomplish this, technical and degradation issues associated with the SOECs will need to be addressed. This report covers various approaches being pursued to model degradation issues in SOECs. An electrochemical model for degradation of SOECs is presented. The model is based on concepts in local thermodynamic equilibrium in systems otherwise in global thermodynamic non-equilibrium. It is shown that electronic conduction through the electrolyte, however small, must be taken into account for determining local oxygen chemical potential,, within the electrolyte. The within the electrolyte may lie out of bounds in relation to values at the electrodes in the electrolyzer mode. Under certain conditions, high pressures can develop in the electrolyte just near the oxygen electrode/electrolyte interface, leading to oxygen electrode delamination. These predictions are in accordance with the reported literature on the subject. Development of high pressures may be avoided by introducing some electronic conduction in the electrolyte. By combining equilibrium thermodynamics, non-equilibrium (diffusion) modeling, and first-principles, atomic scale calculations were performed to understand the degradation mechanisms and provide practical recommendations on how to inhibit and/or completely mitigate them.

  9. Storm Water Management Model Reference Manual Volume II – Hydraulics

    EPA Science Inventory

    SWMM is a dynamic rainfall-runoff simulation model used for single event or long-term (continuous) simulation of runoff quantity and quality from primarily urban areas. The runoff component of SWMM operates on a collection of subcatchment areas that receive precipitation and gene...

  10. Physics Of Eclipsing Binaries. II. Toward the Increased Model Fidelity

    NASA Astrophysics Data System (ADS)

    Prša, A.; Conroy, K. E.; Horvat, M.; Pablo, H.; Kochoska, A.; Bloemen, S.; Giammarco, J.; Hambleton, K. M.; Degroote, P.

    2016-12-01

    The precision of photometric and spectroscopic observations has been systematically improved in the last decade, mostly thanks to space-borne photometric missions and ground-based spectrographs dedicated to finding exoplanets. The field of eclipsing binary stars strongly benefited from this development. Eclipsing binaries serve as critical tools for determining fundamental stellar properties (masses, radii, temperatures, and luminosities), yet the models are not capable of reproducing observed data well, either because of the missing physics or because of insufficient precision. This led to a predicament where radiative and dynamical effects, insofar buried in noise, started showing up routinely in the data, but were not accounted for in the models. PHOEBE (PHysics Of Eclipsing BinariEs; http://phoebe-project.org) is an open source modeling code for computing theoretical light and radial velocity curves that addresses both problems by incorporating missing physics and by increasing the computational fidelity. In particular, we discuss triangulation as a superior surface discretization algorithm, meshing of rotating single stars, light travel time effects, advanced phase computation, volume conservation in eccentric orbits, and improved computation of local intensity across the stellar surfaces that includes the photon-weighted mode, the enhanced limb darkening treatment, the better reflection treatment, and Doppler boosting. Here we present the concepts on which PHOEBE is built and proofs of concept that demonstrate the increased model fidelity.

  11. Nutrient Dynamics in Flooded Wetlands. II: Model Application

    EPA Science Inventory

    In this paper we applied and evaluated the wetland nutrient model described in an earlier paper. Hydrologic and water quality data from a small restored wetland located on Kent Island, Maryland, which is part of the Delmarva Peninsula on the Eastern shores of the Chesapeake Bay...

  12. Demonstrations in Solute Transport Using Dyes: Part II. Modeling.

    ERIC Educational Resources Information Center

    Butters, Greg; Bandaranayake, Wije

    1993-01-01

    A solution of the convection-dispersion equation is used to describe the solute breakthrough curves generated in the demonstrations in the companion paper. Estimation of the best fit model parameters (solute velocity, dispersion, and retardation) is illustrated using the method of moments for an example data set. (Author/MDH)

  13. Nutrient Dynamics in Flooded Wetlands. II: Model Application

    EPA Science Inventory

    In this paper we applied and evaluated the wetland nutrient model described in an earlier paper. Hydrologic and water quality data from a small restored wetland located on Kent Island, Maryland, which is part of the Delmarva Peninsula on the Eastern shores of the Chesapeake Bay...

  14. A general model of invariant chain association with class II major histocompatibility complex proteins.

    PubMed Central

    Lee, C; McConnell, H M

    1995-01-01

    The binding of invariant chain to major histocompatibility complex (MHC) proteins is an important step in processing of MHC class II proteins and in antigen presentation. The question of how invariant chain can bind to all MHC class II proteins is central to understanding these processes. We have employed molecular modeling to predict the structure of class II-associated invariant chain peptide (CLIP)-MHC protein complexes and to ask whether the predicted mode of association could be general across all MHC class II proteins. CLIP fits identically into the MHC class II alleles HLA-DR3, I-Ak, I-Au, and I-Ad, with a consistent pattern of hydrogen bonds, contacts, and hydrophobic burial and without bad contacts. Our model predicts the burial of CLIP residues Met-91 and Met-99 in the deep P1 and P9 anchor pockets and other detailed interactions, which we have compared with available data. The predicted pattern of I-A allele-specific effects on CLIP binding is very similar to that observed experimentally by alanine-scanning mutations of CLIP. Together, these results indicate that CLIP may bind in a single, general way across products of MHC class II alleles. Images Fig. 1 Fig. 2 Fig. 3 PMID:7667280

  15. Spatial modelling of type II diabetes outcomes: a systematic review of approaches used

    PubMed Central

    Baker, Jannah; White, Nicole; Mengersen, Kerrie

    2015-01-01

    With the rising incidence of type II diabetes mellitus (DM II) worldwide, methods to identify high-risk geographical areas have become increasingly important. In this comprehensive review following Cochrane Collaboration guidelines, we outline spatial methods, outcomes and covariates used in all spatial studies involving outcomes of DM II. A total of 1894 potentially relevant citations were identified. Studies were included if spatial methods were used to explore outcomes of DM II or type I and 2 diabetes combined. Descriptive tables were used to summarize information from included studies. Ten spatial studies conducted in the USA, UK and Europe met selection criteria. Three studies used Bayesian generalized linear mixed modelling (GLMM), three used classic generalized linear modelling, one used classic GLMM, two used geographic information systems mapping tools and one compared case:provider ratios across regions. Spatial studies have been effective in identifying high-risk areas and spatial factors associated with DM II outcomes in the USA, UK and Europe, and would be useful in other parts of the world for allocation of additional services to detect and manage DM II early. PMID:26543572

  16. Equilibrium and kinetic modelling of cadmium (II) biosorption by Dried Biomass Aphanothece sp. from aqueous phase

    NASA Astrophysics Data System (ADS)

    Awalina; Harimawan, A.; Haryani, G. S.; Setiadi, T.

    2017-05-01

    The Biosorption of cadmium (II) ions on dried biomass of Aphanothece sp.which previously grown in a photobioreactor system with atmospheric carbon dioxide fed input, was studied in a batch system with respect to initial pH, biomass concentration, contact time, and temperature. The biomass exhibited the highest cadmium (II) uptake capacity at 30ºC, initial pH of 8.0±0.2 in 60 minute and initial cadmium (II) ion concentration of 7.76 mg/L. Maximum biosorption capacities were 16.47 mg/g, 54.95 mg/g and 119.05 mg/g at range of initial cadmium (II) 0.96-3.63 mg/L, 1.99-8.10 mg/L and 6.48-54.38 mg/L, respectively. Uptake kinetics follows the pseudo-second order model while equilibrium is best described by Langmuir isotherm model. Isotherms have been used to determine thermodynamic parameter process (free energy change, enthalpy change and entropy change). FTIR analysis of microalgae biomass revealed the presence of amino acids, carboxyl, hydroxyl, sulfhydryl and carbonyl groups, which are responsible for biosorption of metal ions. During repeated sorption/desorption cycles, the ratio of Cd (II) desorption to biosorption decreased from 81% (at first cycle) to only 27% (at the third cycle). Nevertheless, due to its higher biosorption capability than other adsorbent, Aphanothece sp appears to be a good biosorbent for removing metal Cd (II) ions from aqueous phase.

  17. Solving seismological problems using sgraph program: II-waveform modeling

    SciTech Connect

    Abdelwahed, Mohamed F.

    2012-09-26

    One of the seismological programs to manipulate seismic data is SGRAPH program. It consists of integrated tools to perform advanced seismological techniques. SGRAPH is considered a new system for maintaining and analyze seismic waveform data in a stand-alone Windows-based application that manipulate a wide range of data formats. SGRAPH was described in detail in the first part of this paper. In this part, I discuss the advanced techniques including in the program and its applications in seismology. Because of the numerous tools included in the program, only SGRAPH is sufficient to perform the basic waveform analysis and to solve advanced seismological problems. In the first part of this paper, the application of the source parameters estimation and hypocentral location was given. Here, I discuss SGRAPH waveform modeling tools. This paper exhibits examples of how to apply the SGRAPH tools to perform waveform modeling for estimating the focal mechanism and crustal structure of local earthquakes.

  18. Differential geometry based solvation model II: Lagrangian formulation.

    PubMed

    Chen, Zhan; Baker, Nathan A; Wei, G W

    2011-12-01

    Solvation is an elementary process in nature and is of paramount importance to more sophisticated chemical, biological and biomolecular processes. The understanding of solvation is an essential prerequisite for the quantitative description and analysis of biomolecular systems. This work presents a Lagrangian formulation of our differential geometry based solvation models. The Lagrangian representation of biomolecular surfaces has a few utilities/advantages. First, it provides an essential basis for biomolecular visualization, surface electrostatic potential map and visual perception of biomolecules. Additionally, it is consistent with the conventional setting of implicit solvent theories and thus, many existing theoretical algorithms and computational software packages can be directly employed. Finally, the Lagrangian representation does not need to resort to artificially enlarged van der Waals radii as often required by the Eulerian representation in solvation analysis. The main goal of the present work is to analyze the connection, similarity and difference between the Eulerian and Lagrangian formalisms of the solvation model. Such analysis is important to the understanding of the differential geometry based solvation model. The present model extends the scaled particle theory of nonpolar solvation model with a solvent-solute interaction potential. The nonpolar solvation model is completed with a Poisson-Boltzmann (PB) theory based polar solvation model. The differential geometry theory of surfaces is employed to provide a natural description of solvent-solute interfaces. The optimization of the total free energy functional, which encompasses the polar and nonpolar contributions, leads to coupled potential driven geometric flow and PB equations. Due to the development of singularities and nonsmooth manifolds in the Lagrangian representation, the resulting potential-driven geometric flow equation is embedded into the Eulerian representation for the purpose of

  19. Differential geometry based solvation model II: Lagrangian formulation

    PubMed Central

    Chen, Zhan; Baker, Nathan A.; Wei, G. W.

    2010-01-01

    Solvation is an elementary process in nature and is of paramount importance to more sophisticated chemical, biological and biomolecular processes. The understanding of solvation is an essential prerequisite for the quantitative description and analysis of biomolecular systems. This work presents a Lagrangian formulation of our differential geometry based solvation model. The Lagrangian representation of biomolecular surfaces has a few utilities/advantages. First, it provides an essential basis for biomolecular visualization, surface electrostatic potential map and visual perception of biomolecules. Additionally, it is consistent with the conventional setting of implicit solvent theories and thus, many existing theoretical algorithms and computational software packages can be directly employed. Finally, the Lagrangian representation does not need to resort to artificially enlarged van der Waals radii as often required by the Eulerian representation in solvation analysis. The main goal of the present work is to analyze the connection, similarity and difference between the Eulerian and Lagrangian formalisms of the solvation model. Such analysis is important to the understanding of the differential geometry based solvation model. The present model extends the scaled particle theory (SPT) of nonpolar solvation model with a solvent-solute interaction potential. The nonpolar solvation model is completed with a Poisson-Boltzmann (PB) theory based polar solvation model. The differential geometry theory of surfaces is employed to provide a natural description of solvent-solute interfaces. The minimization of the total free energy functional, which encompasses the polar and nonpolar contributions, leads to coupled potential driven geometric flow and Poisson-Boltzmann equations. Due to the development of singularities and nonsmooth manifolds in the Lagrangian representation, the resulting potential-driven geometric flow equation is embedded into the Eulerian representation for

  20. Electric currents above Saint-Santin. II - Model

    NASA Astrophysics Data System (ADS)

    Mazaudier, C.; Blanc, M.

    1982-04-01

    An empirical model of local horizontal electric current flow seasonal variations above Saint-Santin, France, is generated by means of Ohm's law and a combination of ionosphere electrodynamic parameter local models derived from previous incoherent scatter studies. The Hall and Pedersen, neutral wind-driven and electric field-driven contributions to the total current are explicitly obtained, and the local time variations of the two components of the total, height-integrated horizontal current are compared with the magnetic variation at another location. The zonal component is found to be weak in all seasons, due to the equal and opposite contributions of the electric field and neutral winds. Both the net northward flow of charges revealed by the ionospheric data, and the observed discrepancy between calculated ionospheric currents and magnetic data, suggest that field-aligned currents are flowing from the northern to the southern hemisphere in the authors' longitude sector during at least part of the day.

  1. Model scattering envelopes of young stellar objects. II - Infalling envelopes

    NASA Technical Reports Server (NTRS)

    Whitney, Barbara A.; Hartmann, Lee

    1993-01-01

    We present scattered light images for models of young stellar objects surrounded by dusty envelopes. The envelopes are assumed to have finite angular momentum and are falling in steady flow onto a disk. The model envelopes include holes, such as might be created by energetic bipolar flows. We calculate images using the Monte Carlo method to follow the light scattered in the dusty envelope and circumstellar disk, assuming that the photons originate from the central source. Adopting typical interstellar medium dust opacities and expected mass infall rates for protostars of about 10 exp -6 solar mass/yr, we find that detectable amounts of optical radiation can escape from envelopes falling into a disk as small as about 10-100 AU, depending upon the viewing angle and the size of the bipolar flow cavity. We suggest that the extended optical and near-IR light observed around several young stars is scattered by dusty infalling envelopes rather than disks.

  2. Model scattering envelopes of young stellar objects. II - Infalling envelopes

    NASA Technical Reports Server (NTRS)

    Whitney, Barbara A.; Hartmann, Lee

    1993-01-01

    We present scattered light images for models of young stellar objects surrounded by dusty envelopes. The envelopes are assumed to have finite angular momentum and are falling in steady flow onto a disk. The model envelopes include holes, such as might be created by energetic bipolar flows. We calculate images using the Monte Carlo method to follow the light scattered in the dusty envelope and circumstellar disk, assuming that the photons originate from the central source. Adopting typical interstellar medium dust opacities and expected mass infall rates for protostars of about 10 exp -6 solar mass/yr, we find that detectable amounts of optical radiation can escape from envelopes falling into a disk as small as about 10-100 AU, depending upon the viewing angle and the size of the bipolar flow cavity. We suggest that the extended optical and near-IR light observed around several young stars is scattered by dusty infalling envelopes rather than disks.

  3. Slag Behavior in Gasifiers. Part II: Constitutive Modeling of Slag

    SciTech Connect

    Massoudi, Mehrdad; Wang, Ping

    2013-02-07

    The viscosity of slag and the thermal conductivity of ash deposits are among two of the most important constitutive parameters that need to be studied. The accurate formulation or representations of the (transport) properties of coal present a special challenge of modeling efforts in computational fluid dynamics applications. Studies have indicated that slag viscosity must be within a certain range of temperatures for tapping and the membrane wall to be accessible, for example, between 1,300 °C and 1,500 °C, the viscosity is approximately 25 Pa·s. As the operating temperature decreases, the slag cools and solid crystals begin to form. Since slag behaves as a non-linear fluid, we discuss the constitutive modeling of slag and the important parameters that must be studied. We propose a new constitutive model, where the stress tensor not only has a yield stress part, but it also has a viscous part with a shear rate dependency of the viscosity, along with temperature and concentration dependency, while allowing for the possibility of the normal stress effects. In Part I, we reviewed, identify and discuss the key coal ash properties and the operating conditions impacting slag behavior.

  4. 3D transient model for CO II laser hardening

    NASA Astrophysics Data System (ADS)

    Tani, G.; Orazi, L.; Fortunato, A.; Campana, G.; Ascari, A.

    2008-01-01

    A 3D numerical model for the surface hardening process simulation carried out by means of a CO2 laser source is presented. The model is able to predict the extension of the treated area into the workpiece, the type of the resulting micro-structure and the optimal laser path strategy in order to minimize the micro-structural softening due to the tempering effect. The Fourier equation is solved using the Finite Difference Method (FDM) applied on a generical grid obtained by means of the domain discretization. The resulting time dependent temperature distribution into the workpiece is used for the evaluation of the induced heating cycle. By calculating the cooling velocity, the micro-structure transformation is determined together with the hardness in every point of the domain. The hardness reduction due to the tempering effect is also predictible. The computational times are small and the software is very suitable in industrial environment in the early stage of the process planning when several simulation runs must be performed. The modeling activity was developed by considering the class of the hypo-eutectoid steel. The experimental tests were realized on a C43 steel plate. The good agreement between the theoretical and experimental results is shown.

  5. The use of MAVIS II to integrate the modeling and analysis of explosive valve interactions

    SciTech Connect

    Ng, R.; Kwon, D.M.

    1998-12-31

    The MAVIS II computer program provides for the modeling and analysis of explosive valve interactions. This report describes the individual components of the program and how MAVIS II is used with other available tools to integrate the design and understanding of explosive valves. The rationale and model used for each valve interaction is described. Comparisons of the calculated results with available data have demonstrated the feasibility and accuracy of using MAVIS II for analytical studies of explosive valve interactions. The model used for the explosive or pyrotechnic used as the driving force in explosive valves is the most critical to be understood and modeled. MAVIS II is an advanced version that incorporates a plastic, as well as elastic, modeling of the deformations experienced when plungers are forced into a bore. The inclusion of a plastic model has greatly expanded the use of MAVIS for all categories (opening, closure, or combined) of valves, especially for the closure valves in which the sealing operation requires the plastic deformation of either a plunger or bore over a relatively large area. In order to increase its effectiveness, the use of MAVIS II should be integrated with the results from available experimental hardware. Test hardware such as the Velocity Interferometer System for Any Reflector (VISAR) and Velocity Generator test provide experimental data for accurate comparison of the actual valve functions. Variable Explosive Chamber (VEC) and Constant Explosive Volume (CEV) tests are used to provide the proper explosive equation-of-state for the MAVIS calculations of the explosive driving forces. The rationale and logistics of this integration is demonstrated through an example. A recent valve design is used to demonstrate how MAVIS II can be integrated with experimental tools to provide an understanding of the interactions in this valve.

  6. Calpain-10 Activity Underlies Angiotensin II-Induced Aldosterone Production in an Adrenal Glomerulosa Cell Model

    PubMed Central

    Seremwe, Mutsa; Schnellmann, Rick G.

    2015-01-01

    Aldosterone is a steroid hormone important in the regulation of blood pressure. Aberrant production of aldosterone results in the development and progression of diseases including hypertension and congestive heart failure; therefore, a complete understanding of aldosterone production is important for developing more effective treatments. Angiotensin II (AngII) regulates steroidogenesis, in part through its ability to increase intracellular calcium levels. Calcium can activate calpains, proteases classified as typical or atypical based on the presence or absence of penta-EF-hands, which are involved in various cellular responses. We hypothesized that calpain, in particular calpain-10, is activated by AngII in adrenal glomerulosa cells and underlies aldosterone production. Our studies showed that pan-calpain inhibitors reduced AngII-induced aldosterone production in 2 adrenal glomerulosa cell models, primary bovine zona glomerulosa and human adrenocortical carcinoma (HAC15) cells, as well as CYP11B2 expression in the HAC15 cells. Although AngII induced calpain activation in these cells, typical calpain inhibitors had no effect on AngII-elicited aldosterone production, suggesting a lack of involvement of classical calpains in this process. However, an inhibitor of the atypical calpain, calpain-10, decreased AngII-induced aldosterone production. Consistent with this result, small interfering RNA (siRNA)-mediated knockdown of calpain-10 inhibited aldosterone production and CYP11B2 expression, whereas adenovirus-mediated overexpression of calpain-10 resulted in increased AngII-induced aldosterone production. Our results indicate that AngII-induced activation of calpain-10 in glomerulosa cells underlies aldosterone production and identify calpain-10 or its downstream pathways as potential targets for the development of drug therapies for the treatment of hypertension. PMID:25836666

  7. Modeling of fluidized-bed combustion of coal: Phase II, final reports. Volume IV. FBC-Model-II manual

    SciTech Connect

    Louis, J.F.; Tung, S.E.

    1980-10-01

    This document is the fourth of the seven volume series of our Phase II Final Report. The purpose of this manual is to describe how to access and use M.I.T.'s Fluidized Bed Combustor (FBC) System Program. Presently, the FBC program is stored in a Honeywell Computer System and can be accessed using the Multics interactive system. The intention in writing this manual is to answer the questions that may arise regarding the mechanics of operating the system program, as well as warn the user of possible pitfalls and mistakes that could be made. No attempt is made here to describe the internals of the systems program. The manual describes the procedures an individual would follow to become an active user of the system program. It then explains the various options available for reaching the Multics interactive system on Honeywell 6180 computer on which the program runs. For users outside the Metropolitan Boston area, a public network for data communications is described which is relatively inexpensive. As the system program is approached through Multics using a special command facility TPSA, a separate introduction is provided for Multics TPSA. This facility allows commands appropriate for testing the program and carrying out parametric studies to be executed in a convenient way. Multics TPSA was formulated to meet the needs of the FBC project in particular. Finally, some sample sessions are presented which illustrate the login and logout procedures, the command language, and the data manipulation features of the FBC program. The use of commands helpful in debugging the program is also illustrated.

  8. Hollow cathode modeling: II. Physical analysis and parametric study

    NASA Astrophysics Data System (ADS)

    Sary, Gaétan; Garrigues, Laurent; Boeuf, Jean-Pierre

    2017-05-01

    A numerical emissive hollow cathode model which couples plasma and thermal aspects of the NASA NSTAR cathode has been presented in a companion paper and simulation results obtained using the plasma model were compared to experimental data. We now compare simulation results with measurements using the full coupled model. Inside the cathode, the simulated plasma density profile agrees with the experimental data up to the ±50% experimental uncertainty while the simulated emitter temperature differs from measurements by at most 5 K. We then proceed to an analysis of the cathode discharge both inside the cathode where electron emission is dominant and outside in the near plume where electron transport instabilities are important. As observed previously in the literature, the total emitted electron current is much larger (34 {{A}}) than the set discharge current collected at the anode (13 {{A}}) while ionization plays a negligible role. Extracted electrons are emitted from a region much shorter than the full emitter (0.9 {{cm}} versus 2.5 {{cm}}). The influence of an applied axial magnetic field in the plume is also assessed and we observe that it leads to a 10-fold increase of the plasma density 1 cm downstream of the orifice entrance while the simulated discharge potential at the anode is increased from 10 {{V}} up to 35.5 {{V}}. Lastly, we perform a parametric study on both the operating point (discharge current, mass flow rate) and design (inner radius) of the cathode. The simulated useful operating envelope is shown to be limited at low discharge current mostly because of the probable ion sputtering of the emitter and at high discharge current because of emitter evaporation, plasma oscillations and sputtering of the keeper electrode. The behavior of the cathode is also analyzed w.r.t. its internal radius and simulation results show that the useful emitter length scales linearly with the cathode radius.

  9. Biogeochemical modelling of the tropical Pacific Ocean. II: Iron biogeochemistry

    NASA Astrophysics Data System (ADS)

    Christian, J. R.; Verschell, M. A.; Murtugudde, R.; Busalacchi, A. J.; McClain, C. R.

    A coupled physical-biogeochemical model of the tropical Pacific Ocean with simultaneous iron and nitrogen limitation was developed to study questions of iron biogeochemistry, its effects on upper ocean production, and ultimately the biogeochemical cycles of the other elements. The model results suggest that iron limitation is ubiquitous in the equatorial Pacific, and extends further west than is generally believed unless there are significant inputs of geothermal iron at quite shallow depths. Most model parameters (e.g., iron solubility, scavenging rates, Fe : N ratios) must be near the limit of their generally accepted range of values in order to prevent elevated surface nitrate concentrations from spreading further into the warm pool than is observed. Transport of geothermal iron in the equatorial undercurrent (EUC) provides a possible mechanism for limiting surface nitrate in the warm pool, but the source must be near the upper boundary of the EUC to provide iron to the surface west of the dateline. Accumulations of ammonium in the western Pacific appear to result from the exhaustion of iron in upwelled water before nitrogen. The realism of the simulation is limited primarily by lack of information about the abundance and distribution of dissolved iron; the assumption of constant Fe : N ratios and the magnitude, distribution and solubility of the aeolian iron flux are also important sources of uncertainty. The sensitivity of the simulation to the way that iron is initialized in the western Pacific thermocline emphasizes the importance of the equatorial undercurrent throughout the tropical Pacific and the need for iron observations in this region.

  10. Modeling direct interband tunneling. II. Lower-dimensional structures

    SciTech Connect

    Pan, Andrew; Chui, Chi On

    2014-08-07

    We investigate the applicability of the two-band Hamiltonian and the widely used Kane analytical formula to interband tunneling along unconfined directions in nanostructures. Through comparisons with k·p and tight-binding calculations and quantum transport simulations, we find that the primary correction is the change in effective band gap. For both constant fields and realistic tunnel field-effect transistors, dimensionally consistent band gap scaling of the Kane formula allows analytical and numerical device simulations to approximate non-equilibrium Green's function current characteristics without arbitrary fitting. This allows efficient first-order calibration of semiclassical models for interband tunneling in nanodevices.

  11. Quantum chaos in the nuclear collective model. II. Peres lattices.

    PubMed

    Stránský, Pavel; Hruska, Petr; Cejnar, Pavel

    2009-06-01

    This is a continuation of our paper [Phys. Rev. E 79, 046202 (2009)] devoted to signatures of quantum chaos in the geometric collective model of atomic nuclei. We apply the method by Peres to study ordered and disordered patterns in quantum spectra drawn as lattices in the plane of energy vs average of a chosen observable. Good qualitative agreement with standard measures of chaos is manifested. The method provides an efficient tool for studying structural changes in eigenstates across quantum spectra of general systems.

  12. DETAILED DECOMPOSITION OF GALAXY IMAGES. II. BEYOND AXISYMMETRIC MODELS

    SciTech Connect

    Peng, Chien Y.; Ho, Luis C.; Impey, Chris D.; Rix, Hans-Walter E-mail: lho@obs.carnegiescience.ed E-mail: rix@mpia-hd.mpg.d

    2010-06-15

    We present a two-dimensional (2D) fitting algorithm (GALFIT, ver. 3) with new capabilities to study the structural components of galaxies and other astronomical objects in digital images. Our technique improves on previous 2D fitting algorithms by allowing for irregular, curved, logarithmic and power-law spirals, ring, and truncated shapes in otherwise traditional parametric functions like the Sersic, Moffat, King, Ferrer, etc., profiles. One can mix and match these new shape features freely, with or without constraints, and apply them to an arbitrary number of model components of numerous profile types, so as to produce realistic-looking galaxy model images. Yet, despite the potential for extreme complexity, the meaning of the key parameters like the Sersic index, effective radius, or luminosity remains intuitive and essentially unchanged. The new features have an interesting potential for use to quantify the degree of asymmetry of galaxies, to quantify low surface brightness tidal features beneath and beyond luminous galaxies, to allow more realistic decompositions of galaxy subcomponents in the presence of strong rings and spiral arms, and to enable ways to gauge the uncertainties when decomposing galaxy subcomponents. We illustrate these new features by way of several case studies that display various levels of complexity.

  13. Simulation of Slag Freeze Layer Formation: Part II: Numerical Model

    NASA Astrophysics Data System (ADS)

    Guevara, Fernando J.; Irons, Gordon A.

    2011-08-01

    The experiments from Part I with CaCl2-H2O solidification in a differentially heated, square cavity were simulated in two dimensions using a control volume technique in a fixed grid. The test conditions and physical properties of the fluid resulted in Prandtl and Rayleigh numbers in the range of 50 and 2.1 × 108, respectively, and the solidification was observed to be planar with dispersed solid particles. In the mathematical model, temperature-dependent viscosity and density functions were employed. To suppress velocities in the solid phase, various models were tested, and a high effective viscosity was found most appropriate. The results compare well with the experiments in terms of solid layer growth, horizontal and vertical velocities, heat transfer coefficients, and temperature distributions. Hydrodynamic boundary layers on the solidified front and on the hot vertical wall tend to be nonsymmetric, as well on the top and bottom adiabatic walls. The high viscosity value imposed on the two-phase zone affects the velocity profile close to the solid front and modifies the heat transfer rate.

  14. Corroborative models of the cobalt(II) inhibited Fe/Mn superoxide dismutases.

    PubMed

    Scarpellini, Marciela; Wu, Amy J; Kampf, Jeff W; Pecoraro, Vincent L

    2005-07-11

    Attempting to model superoxide dismutase (SOD) enzymes, we designed two new N3O-donor ligands to provide the same set of donor atoms observed in the active site of these enzymes: K(i)Pr2TCMA (potassium 1,4-diisopropyl-1,4,7-triazacyclononane-N-acetate) and KBPZG (potassium N,N-bis(3,5-dimethylpyrazolylmethyl) glycinate). Five new Co(II) complexes (1-5) were obtained and characterized by X-ray crystallography, mass spectrometry, electrochemistry, magnetochemistry, UV-vis, and electron paramagnetic resonance (EPR) spectroscopies. The crystal structures of 1 and 3-5 revealed five-coordinate complexes, whereas complex 2 is six-coordinate. The EPR data of complexes 3 and 4 agree with those of the Co(II)-substituted SOD, which strongly support the proposition that the active site of the enzyme structurally resembles these models. The redox behavior of complexes 1-5 clearly demonstrates the stabilization of the Co(II) state in the ligand field provided by these ligands. The irreversibility displayed by all of the complexes is probably related to an electron-transfer process followed by a rearrangement of the geometry around the metal center for complexes 1 and 3-5 that probably changes from a trigonal bipyramidal (high spin, d7) to octahedral (low spin, d6) as Co(II) is oxidized to Co(III), which is also expected to be accompanied by a spin-state conversion. As the redox potentials to convert the Co(II) to Co(III) are high, it can be inferred that the redox potential of the Co(II)-substituted SOD may be outside the range required to convert the superoxide radical (O2*-) to hydrogen peroxide, and this is sufficient to explain the inactivity of the enzyme. Finally, the complexes reported here are the first corroborative structural models of the Co(II)-substituted SOD.

  15. THE FORMATION OF IRIS DIAGNOSTICS. I. A QUINTESSENTIAL MODEL ATOM OF Mg II AND GENERAL FORMATION PROPERTIES OF THE Mg II h and k LINES

    SciTech Connect

    Leenaarts, J.; Pereira, T. M. D.; Carlsson, M.; De Pontieu, B.; Uitenbroek, H. E-mail: tiago.pereira@astro.uio.no E-mail: bdp@lmsal.com

    2013-08-01

    NASA's Interface Region Imaging Spectrograph (IRIS) space mission will study how the solar atmosphere is energized. IRIS contains an imaging spectrograph that covers the Mg II h and k lines as well as a slit-jaw imager centered at Mg II k. Understanding the observations will require forward modeling of Mg II h and k line formation from three-dimensional (3D) radiation-MHD models. This paper is the first in a series where we undertake this forward modeling. We discuss the atomic physics pertinent to h and k line formation, present a quintessential model atom that can be used in radiative transfer computations, and discuss the effect of partial redistribution (PRD) and 3D radiative transfer on the emergent line profiles. We conclude that Mg II h and k can be modeled accurately with a four-level plus continuum Mg II model atom. Ideally radiative transfer computations should be done in 3D including PRD effects. In practice this is currently not possible. A reasonable compromise is to use one-dimensional PRD computations to model the line profile up to and including the central emission peaks, and use 3D transfer assuming complete redistribution to model the central depression.

  16. Polarized Molecular Orbital Model Chemistry. II. The PMO Method.

    PubMed

    Zhang, Peng; Fiedler, Luke; Leverentz, Hannah R; Truhlar, Donald G; Gao, Jiali

    2011-04-12

    We present a new semiempirical molecular orbital method based on neglect of diatomic differential overlap. This method differs from previous NDDO-based methods in that we include p orbitals on hydrogen atoms to provide a more realistic modeling of polarizability. As in AM1-D and PM3-D, we also include damped dispersion. The formalism is based on the original MNDO one, but in the process of parameterization we make some specific changes to some of the functional forms. The present article is a demonstration of the capability of the new approach, and it presents a successful parametrization for compounds composed only of hydrogen and oxygen atoms, including the important case of water clusters.

  17. Modeling extracellular electrical stimulation: II. Computational validation and numerical results.

    PubMed

    Tahayori, Bahman; Meffin, Hamish; Dokos, Socrates; Burkitt, Anthony N; Grayden, David B

    2012-12-01

    The validity of approximate equations describing the membrane potential under extracellular electrical stimulation (Meffin et al 2012 J. Neural Eng. 9 065005) is investigated through finite element analysis in this paper. To this end, the finite element method is used to simulate a cylindrical neurite under extracellular stimulation. Laplace's equations with appropriate boundary conditions are solved numerically in three dimensions and the results are compared to the approximate analytic solutions. Simulation results are in agreement with the approximate analytic expressions for longitudinal and transverse modes of stimulation. The range of validity of the equations describing the membrane potential for different values of stimulation and neurite parameters are presented as well. The results indicate that the analytic approach can be used to model extracellular electrical stimulation for realistic physiological parameters with a high level of accuracy.

  18. Polarized Molecular Orbital Model Chemistry. II. The PMO Method

    PubMed Central

    Zhang, Peng; Fiedler, Luke; Leverentz, Hannah R.; Truhlar, Donald G.; Gao, Jiali

    2012-01-01

    We present a new semiempirical molecular orbital method based on neglect of diatomic differential overlap. This method differs from previous NDDO-based methods in that we include p orbitals on hydrogen atoms to provide a more realistic modeling of polarizability. As in AM1-D and PM3-D, we also include damped dispersion. The formalism is based on the original MNDO one, but in the process of parameterization we make some specific changes to some of the functional forms. The present article is a demonstration of the capability of the new approach, and it presents a successful parametrization for compounds composed only of hydrogen and oxygen atoms, including the important case of water clusters. PMID:23378824

  19. nIFTy galaxy cluster simulations - II. Radiative models

    NASA Astrophysics Data System (ADS)

    Sembolini, Federico; Elahi, Pascal Jahan; Pearce, Frazer R.; Power, Chris; Knebe, Alexander; Kay, Scott T.; Cui, Weiguang; Yepes, Gustavo; Beck, Alexander M.; Borgani, Stefano; Cunnama, Daniel; Davé, Romeel; February, Sean; Huang, Shuiyao; Katz, Neal; McCarthy, Ian G.; Murante, Giuseppe; Newton, Richard D. A.; Perret, Valentin; Puchwein, Ewald; Saro, Alexandro; Schaye, Joop; Teyssier, Romain

    2016-07-01

    We have simulated the formation of a massive galaxy cluster (M_{200}^crit = 1.1 × 1015 h-1 M⊙) in a Λ cold dark matter universe using 10 different codes (RAMSES, 2 incarnations of AREPO and 7 of GADGET), modelling hydrodynamics with full radiative subgrid physics. These codes include smoothed-particle hydrodynamics (SPH), spanning traditional and advanced SPH schemes, adaptive mesh and moving mesh codes. Our goal is to study the consistency between simulated clusters modelled with different radiative physical implementations - such as cooling, star formation and thermal active galactic nucleus (AGN) feedback. We compare images of the cluster at z = 0, global properties such as mass, and radial profiles of various dynamical and thermodynamical quantities. We find that, with respect to non-radiative simulations, dark matter is more centrally concentrated, the extent not simply depending on the presence/absence of AGN feedback. The scatter in global quantities is substantially higher than for non-radiative runs. Intriguingly, adding radiative physics seems to have washed away the marked code-based differences present in the entropy profile seen for non-radiative simulations in Sembolini et al.: radiative physics + classic SPH can produce entropy cores, at least in the case of non cool-core clusters. Furthermore, the inclusion/absence of AGN feedback is not the dividing line -as in the case of describing the stellar content - for whether a code produces an unrealistic temperature inversion and a falling central entropy profile. However, AGN feedback does strongly affect the overall stellar distribution, limiting the effect of overcooling and reducing sensibly the stellar fraction.

  20. Functional Models for the Oxygen-Evolving Complex of Photosystem II

    PubMed Central

    Cady, Clyde W.; Crabtree, Robert H.; Brudvig, Gary W.

    2010-01-01

    In the last ten years, a number of advances have been made in the study of the oxygen-evolving complex (OEC) of photosystem II (PSII). Along with this new understanding of the natural system has come rapid advance in chemical models of this system. The advance of PSII model chemistry is seen most strikingly in the area of functional models where the few known systems available when this topic was last reviewed has grown into two families of model systems. In concert with this work, numerous mechanistic proposals for photosynthetic water oxidation have been proposed. Here, we review the recent efforts in functional model chemistry of the oxygen-evolving complex of photosystem II. PMID:21037800

  1. Electronic structure of nickel(II) and zinc(II) borohydrides from spectroscopic measurements and computational modeling.

    PubMed

    Desrochers, Patrick J; Sutton, Christopher A; Abrams, Micah L; Ye, Shengfa; Neese, Frank; Telser, Joshua; Ozarowski, Andrew; Krzystek, J

    2012-03-05

    The previously reported Ni(II) complex, Tp*Ni(κ(3)-BH(4)) (Tp* = hydrotris(3,5-dimethylpyrazolyl)borate anion), which has an S = 1 spin ground state, was studied by high-frequency and -field electron paramagnetic resonance (HFEPR) spectroscopy as a solid powder at low temperature, by UV-vis-NIR spectroscopy in the solid state and in solution at room temperature, and by paramagnetic (11)B NMR. HFEPR provided its spin Hamiltonian parameters: D = 1.91(1) cm(-1), E = 0.285(8) cm(-1), g = [2.170(4), 2.161(3), 2.133(3)]. Similar, but not identical parameters were obtained for its borodeuteride analogue. The previously unreported complex, Tp*Zn(κ(2)-BH(4)), was prepared, and IR and NMR spectroscopy allowed its comparison with analogous closed shell borohydride complexes. Ligand-field theory was used to model the electronic transitions in the Ni(II) complex successfully, although it was less successful at reproducing the zero-field splitting (zfs) parameters. Advanced computational methods, both density functional theory (DFT) and ab initio wave function based approaches, were applied to these Tp*MBH(4) complexes to better understand the interaction between these metals and borohydride ion. DFT successfully reproduced bonding geometries and vibrational behavior of the complexes, although it was less successful for the spin Hamiltonian parameters of the open shell Ni(II) complex. These were instead best described using ab initio methods. The origin of the zfs in Tp*Ni(κ(3)-BH(4)) is described and shows that the relatively small magnitude of D results from several spin-orbit coupling (SOC) interactions of large magnitude, but with opposite sign. Spin-spin coupling (SSC) is also shown to be significant, a point that is not always appreciated in transition metal complexes. Overall, a picture of bonding and electronic structure in open and closed shell late transition metal borohydrides is provided, which has implications for the use of these complexes in catalysis and

  2. First results of GERDA Phase II and consistency with background models

    NASA Astrophysics Data System (ADS)

    Agostini, M.; Allardt, M.; Bakalyarov, A. M.; Balata, M.; Barabanov, I.; Baudis, L.; Bauer, C.; Bellotti, E.; Belogurov, S.; Belyaev, S. T.; Benato, G.; Bettini, A.; Bezrukov, L.; Bode1, T.; Borowicz, D.; Brudanin, V.; Brugnera, R.; Caldwell, A.; Cattadori, C.; Chernogorov, A.; D'Andrea, V.; Demidova, E. V.; Di Marco, N.; Domula, A.; Doroshkevich, E.; Egorov, V.; Falkenstein, R.; Frodyma, N.; Gangapshev, A.; Garfagnini, A.; Gooch, C.; Grabmayr, P.; Gurentsov, V.; Gusev, K.; Hakenmüller, J.; Hegai, A.; Heisel, M.; Hemmer, S.; Hofmann, W.; Hult, M.; Inzhechik, L. V.; Janicskó Csáthy, J.; Jochum, J.; Junker, M.; Kazalov, V.; Kihm, T.; Kirpichnikov, I. V.; Kirsch, A.; Kish, A.; Klimenko, A.; Kneißl, R.; Knöpfle, K. T.; Kochetov, O.; Kornoukhov, V. N.; Kuzminov, V. V.; Laubenstein, M.; Lazzaro, A.; Lebedev, V. I.; Lehnert, B.; Liao, H. Y.; Lindner, M.; Lippi, I.; Lubashevskiy, A.; Lubsandorzhiev, B.; Lutter, G.; Macolino, C.; Majorovits, B.; Maneschg, W.; Medinaceli, E.; Miloradovic, M.; Mingazheva, R.; Misiaszek, M.; Moseev, P.; Nemchenok, I.; Palioselitis, D.; Panas, K.; Pandola, L.; Pelczar, K.; Pullia, A.; Riboldi, S.; Rumyantseva, N.; Sada, C.; Salamida, F.; Salathe, M.; Schmitt, C.; Schneider, B.; Schönert, S.; Schreiner, J.; Schulz, O.; Schütz, A.-K.; Schwingenheuer, B.; Selivanenko, O.; Shevzik, E.; Shirchenko, M.; Simgen, H.; Smolnikov, A.; Stanco, L.; Vanhoefer, L.; Vasenko, A. A.; Veresnikova, A.; von Sturm, K.; Wagner, V.; Wegmann, A.; Wester, T.; Wiesinger, C.; Wojcik, M.; Yanovich, E.; Zhitnikov, I.; Zhukov, S. V.; Zinatulina, D.; Zuber, K.; Zuzel, G.

    2017-01-01

    The GERDA (GERmanium Detector Array) is an experiment for the search of neutrinoless double beta decay (0νββ) in 76Ge, located at Laboratori Nazionali del Gran Sasso of INFN (Italy). GERDA operates bare high purity germanium detectors submersed in liquid Argon (LAr). Phase II of data-taking started in Dec 2015 and is currently ongoing. In Phase II 35 kg of germanium detectors enriched in 76Ge including thirty newly produced Broad Energy Germanium (BEGe) detectors is operating to reach an exposure of 100 kg·yr within about 3 years data taking. The design goal of Phase II is to reduce the background by one order of magnitude to get the sensitivity for T1/20ν = O≤ft( {{{10}26}} \\right){{ yr}}. To achieve the necessary background reduction, the setup was complemented with LAr veto. Analysis of the background spectrum of Phase II demonstrates consistency with the background models. Furthermore 226Ra and 232Th contamination levels consistent with screening results. In the first Phase II data release we found no hint for a 0νββ decay signal and place a limit of this process T1/20ν > 5.3 \\cdot {1025} yr (90% C.L., sensitivity 4.0·1025 yr). First results of GERDA Phase II will be presented.

  3. Expression of collagen types I and II on articular cartilage in a rat knee contracture model.

    PubMed

    Hagiwara, Yoshihiro; Ando, Akira; Chimoto, Eiichi; Tsuchiya, Masahiro; Takahashi, Ichiro; Sasano, Yasuyuki; Onoda, Yoshito; Suda, Hideaki; Itoi, Eiji

    2010-01-01

    The purpose of our study was to clarify the expression patterns of collagen types I and II on articular cartilage after immobilization in a rat knee contracture model in 3 specific areas (noncontact area, transitional area, contact area). The unilateral knee joints of adult male rats were rigidly immobilized at 150 degrees of flexion using screws and a rigid plastic plate. Sham-operated animals had holes drilled in the femur and the tibia and screws inserted but were not plated. The expression patterns of collagen types I and II in each area were evaluated by in situ hybridization (ISH), immunohistochemistry (IHC), and quantitative real-time polymerase chain reaction (qPCR). The expression of collagen type II in the noncontact area was decreased by ISH but appeared unchanged when examined by IHC. In the transitional and contact areas, the expression of collagen type II was initially shown to have decreased and then increased at the hypertrophic chondrocytes by ISH but appeared decreased by IHC. Quantitative PCR revealed the decreased expression of type II collagen in the contact area. Immunostaining of collagen type I was increased at the noncontact area and transitional areas. Alterations of collagen types I and II expression may also affect the degeneration of articular cartilage after immobilization and the changes were different in the three areas.

  4. An Extended Equation of State Modeling Method II. Mixtures

    NASA Astrophysics Data System (ADS)

    Scalabrin, G.; Marchi, P.; Stringari, P.; Richon, D.

    2006-09-01

    This work is the extension of previous work dedicated to pure fluids. The same method is extended to the representation of thermodynamic properties of a mixture through a fundamental equation of state in terms of the Helmholtz energy. The proposed technique exploits the extended corresponding-states concept of distorting the independent variables of a dedicated equation of state for a reference fluid using suitable scale factor functions to adapt the equation to experimental data of a target system. An existing equation of state for the target mixture is used instead of an equation for the reference fluid, completely avoiding the need for a reference fluid. In particular, a Soave-Redlich-Kwong cubic equation with van der Waals mixing rules is chosen. The scale factors, which are functions of temperature, density, and mole fraction of the target mixture, are expressed in the form of a multilayer feedforward neural network, whose coefficients are regressed by minimizing a suitable objective function involving different kinds of mixture thermodynamic data. As a preliminary test, the model is applied to five binary and two ternary haloalkane mixtures, using data generated from existing dedicated equations of state for the selected mixtures. The results show that the method is robust and straightforward for the effective development of a mixture- specific equation of state directly from experimental data.

  5. Dynamic spreading of nanofluids on solids part II: modeling.

    PubMed

    Liu, Kuan-Liang; Kondiparty, Kirtiprakash; Nikolov, Alex D; Wasan, Darsh

    2012-11-27

    Recent studies on the spreading phenomena of liquid dispersions of nanoparticles (nanofluids) have revealed that the self-layering and two-dimensional structuring of nanoparticles in the three-phase contact region exert structural disjoining pressure, which drives the spreading of nanofluids by forming a continuous wedge film between the liquid (e.g., oil) and solid surface. Motivated by the practical applications of the phenomenon and experimental results reported in Part I of this two-part series, we thoroughly investigated the spreading dynamics of nanofluids against an oil drop on a solid surface. With the Laplace equation as a starting point, the spreading process is modeled by Navier-Stokes equations through the lubrication approach, which considers the structural disjoining pressure, gravity, and van der Waals force. The temporal interface profile and advancing inner contact line velocity of nanofluidic films are analyzed through varying the effective nanoparticle concentration, the outer contact angle, the effective nanoparticle size, and capillary pressure. It is found that a fast and spontaneous advance of the inner contact line movement can be obtained by increasing the nanoparticle concentration, decreasing the nanoparticle size, and/or decreasing the interfacial tension. Once the nanofluidic film is formed, the advancing inner contact line movement reaches a constant velocity, which is independent of the outer contact angle if the interfacial tension is held constant.

  6. TURBULENT CONVECTION MODEL IN THE OVERSHOOTING REGION. II. THEORETICAL ANALYSIS

    SciTech Connect

    Zhang, Q. S.; Li, Y. E-mail: ly@ynao.ac.cn

    2012-05-01

    Turbulent convection models (TCMs) are thought to be good tools to deal with the convective overshooting in the stellar interior. However, they are too complex to be applied to calculations of stellar structure and evolution. In order to understand the physical processes of the convective overshooting and to simplify the application of TCMs, a semi-analytic solution is necessary. We obtain the approximate solution and asymptotic solution of the TCM in the overshooting region, and find some important properties of the convective overshooting. (1) The overshooting region can be partitioned into three parts: a thin region just outside the convective boundary with high efficiency of turbulent heat transfer, a power-law dissipation region of turbulent kinetic energy in the middle, and a thermal dissipation area with rapidly decreasing turbulent kinetic energy. The decaying indices of the turbulent correlations k, u{sub r}'T'-bar, and T'T'-bar are only determined by the parameters of the TCM, and there is an equilibrium value of the anisotropic degree {omega}. (2) The overshooting length of the turbulent heat flux u{sub r}'T'-bar is about 1H{sub k} (H{sub k} = |dr/dln k|). (3) The value of the turbulent kinetic energy at the convective boundary k{sub C} can be estimated by a method called the maximum of diffusion. Turbulent correlations in the overshooting region can be estimated by using k{sub C} and exponentially decreasing functions with the decaying indices.

  7. Theory of stellar convection - II. First stellar models

    NASA Astrophysics Data System (ADS)

    Pasetto, S.; Chiosi, C.; Chiosi, E.; Cropper, M.; Weiss, A.

    2016-07-01

    We present here the first stellar models on the Hertzsprung-Russell diagram, in which convection is treated according to the new scale-free convection theory (SFC theory) by Pasetto et al. The aim is to compare the results of the new theory with those from the classical, calibrated mixing-length (ML) theory to examine differences and similarities. We integrate the equations describing the structure of the atmosphere from the stellar surface down to a few per cent of the stellar mass using both ML theory and SFC theory. The key temperature over pressure gradients, the energy fluxes, and the extension of the convective zones are compared in both theories. The analysis is first made for the Sun and then extended to other stars of different mass and evolutionary stage. The results are adequate: the SFC theory yields convective zones, temperature gradients ∇ and ∇e, and energy fluxes that are very similar to those derived from the `calibrated' MT theory for main-sequence stars. We conclude that the old scale dependent ML theory can now be replaced with a self-consistent scale-free theory able to predict correct results, as it is more physically grounded than the ML theory. Fundamentally, the SFC theory offers a deeper insight of the underlying physics than numerical simulations.

  8. Control of gravitropic orientation. II. Dual receptor model for gravitropism

    NASA Technical Reports Server (NTRS)

    LaMotte, Clifford E.; Pickard, Barbara G.

    2004-01-01

    Gravitropism of vascular plants has been assumed to require a single gravity receptor mechanism. However, based on the evidence in Part I of this study, we propose that maize roots require two. The first mechanism is without a directional effect and, by itself, cannot give rise to tropism. Its role is quantitative facilitation of the second mechanism, which is directional like the gravitational force itself and provides the impetus for tropic curvature. How closely coupled the two mechanisms may be is, as yet, unclear. The evidence for dual receptors supports a general model for roots. When readiness for gravifacilitation, or gravifacilitation itself, is constitutive, orthogravitropic curvature can go to completion. If not constitutively enabled, gravifacilitation can be weak in the absence of light and water deficit or strong in the presence of light and water deficit. In either case, it can decay and permit roots to assume reproducible non-vertical orientations (plagiogravitropic or plagiotropic orientations) without using non-vertical setpoints. In this way roots are deployed in a large volume of soil. Gravitropic behaviours in shoots are more diverse than in roots, utilising oblique and horizontal as well as vertical setpoints. As a guide to future experiments, we assess how constitutive v. non-constitutive modes of gravifacilitation might contribute to behaviours based on each kind of setpoint.

  9. Unified Model of the rf Plasma Sheath, Part II

    NASA Astrophysics Data System (ADS)

    Riley, Merle

    1996-10-01

    By developing an approximation to the first integral of the Poisson equation, one can obtain solutions for the current-voltage characteristics of an rf plasma sheath that are valid over the whole range of inertial response of the ions to an imposed rf voltage or current. (M.E.Riley, 1995 GEC, abstract QA5, published in Bull. Am. Phys. Soc., 40, 1587 (1995).) The theory has been shown to adequately reproduce current-voltage characteristics of two extreme cases (M.A. Lieberman, IEEE Trans. Plasma Sci. 16, 638 (1988). A. Metze, D.W. Ernie, and H.J.Oskam, J.Appl.Phys., 60, 3081 (1986).) of ion response. In this work I show the effect of different conventions for connecting the sheath model to the bulk plasma. Modifications of the Mach number and a finite electric field at the Bohm point are natural choices. The differences are examined for a sheath in a high density Ar plasma and are found to be insignificant. A theoretical argument favors the electric field modification. *Work performed at Sandia National Labs and supported by US DoE under contract DE-AC04-94AL85000.

  10. Prehension synergies during nonvertical grasping, II: Modeling and optimization.

    PubMed

    Pataky, Todd C; Latash, Mark L; Zatsiorsky, Vladimir M

    2004-10-01

    This study examines various optimization criteria as potential sources of constraints that eliminate (or at least reduce the degree of) mechanical redundancy in prehension. A model of nonvertical grasping mimicking the experimental conditions of Pataky et al. (current issue) was developed and numerically optimized. Several cost functions compared well with experimental data including energylike functions, entropylike functions, and a ''motor command'' function. A tissue deformation function failed to predict finger forces. In the prehension literature, the ''safety margin'' (SM) measure has been used to describe grasp quality. We demonstrate here that the SM is an inappropriate measure for nonvertical grasps. We introduce a new measure, the ''generalized safety margin'' (GSM), which reduces to the SM for vertical and two-digit grasps. It was found that a close-to-constant GSM accounts for many of the finger force patterns that are observed when grasping an object oriented arbitrarily with respect to the gravity field. It was hypothesized that, when determining finger forces, the CNS assumes that a grasped object is more slippery than it actually is. An ''operative friction coefficient'' of approximately 30% of the actual coefficient accounted for the offset between experimental and optimized data. The data suggest that the CNS utilizes an optimization strategy when coordinating finger forces during grasping.

  11. The Framed Standard Model (II) -- A First Test Against Experiment

    NASA Astrophysics Data System (ADS)

    Chan, Hong-Mo; Tsou, Sheung Tsun

    Apart from the qualitative features described in Paper I (Ref. 1), the renormalization group equation derived for the rotation of the fermion mass matrices are amenable to quantitative study. The equation depends on a coupling and a fudge factor and, on integration, on 3 integration constants. Its application to data analysis, however, requires the input from experiment of the heaviest generation masses mt,mb,mτ,mυ3 all of which are known, except for mυ3. Together then with the theta-angle in the QCD action, there are in all 7 real unknown parameters. Determining these 7 parameters by fitting to the experimental values of the masses mc, mυ, me, the CKM elements |Vus|, |Vub|, and the neutrino oscillation angle sin2 θ13, one can then calculate and compare with experiment the following 12 other quantities ms, mu/md, |Vud|, |Vcs|, |Vtb|, |Vcd|, |Vcb|, |Vts|, |Vtd|, J, sin2 2θ12, sin2 2θ23, and the results all agree reasonably well with data, often to within the stringent experimental error now achieved. Counting the predictions not yet measured by experiment, this means that 17 independent parameters of the standard model are now replaced by 7 in the FSM...

  12. Control of gravitropic orientation. II. Dual receptor model for gravitropism

    NASA Technical Reports Server (NTRS)

    LaMotte, Clifford E.; Pickard, Barbara G.

    2004-01-01

    Gravitropism of vascular plants has been assumed to require a single gravity receptor mechanism. However, based on the evidence in Part I of this study, we propose that maize roots require two. The first mechanism is without a directional effect and, by itself, cannot give rise to tropism. Its role is quantitative facilitation of the second mechanism, which is directional like the gravitational force itself and provides the impetus for tropic curvature. How closely coupled the two mechanisms may be is, as yet, unclear. The evidence for dual receptors supports a general model for roots. When readiness for gravifacilitation, or gravifacilitation itself, is constitutive, orthogravitropic curvature can go to completion. If not constitutively enabled, gravifacilitation can be weak in the absence of light and water deficit or strong in the presence of light and water deficit. In either case, it can decay and permit roots to assume reproducible non-vertical orientations (plagiogravitropic or plagiotropic orientations) without using non-vertical setpoints. In this way roots are deployed in a large volume of soil. Gravitropic behaviours in shoots are more diverse than in roots, utilising oblique and horizontal as well as vertical setpoints. As a guide to future experiments, we assess how constitutive v. non-constitutive modes of gravifacilitation might contribute to behaviours based on each kind of setpoint.

  13. Triad model of education (II) and instructional engineering.

    PubMed

    Vargas, E A

    2007-11-01

    Despite the money and sweat that go into new instructional technologies, they do not produce the overall high level of student performances that societies seek. More effective teaching calls for a profound solution. It requires a coordinate triad of factors: a proper science, the correct organizational structure, and an engineering instructional technology. This second of a series of articles on the Triad Model of Education concentrates on instructional engineering. The instructional engineering drawn from the science is contingency-based. Contingency-based instructional systems always handle the inevitable two components of instruction: the repertoires of students and the setups that shape those repertoires. The setup component features five elements: subject matter, objectives, quality control, presentation modes, and logistics. The repertoire component consists of the governance of repertoires-event and lingual governed, the type of repertoire-knowing, solving, and creating, and the variability of the repertoire--convergent and divergent. These elements, and their required engineering, reveal an instructional task more complex than previously considered. Progress with such complexity occurs only when all components of the triad are in place.

  14. Modeling the distribution of Mg II absorbers around galaxies using background galaxies and quasars

    SciTech Connect

    Bordoloi, R.; Lilly, S. J.; Kacprzak, G. G.; Churchill, C. W.

    2014-04-01

    We present joint constraints on the distribution of Mg II absorption around high redshift galaxies obtained by combining two orthogonal probes, the integrated Mg II absorption seen in stacked background galaxy spectra and the distribution of parent galaxies of individual strong Mg II systems as seen in the spectra of background quasars. We present a suite of models that can be used to predict, for different two- and three-dimensional distributions, how the projected Mg II absorption will depend on a galaxy's apparent inclination, the impact parameter b and the azimuthal angle between the projected vector to the line of sight and the projected minor axis. In general, we find that variations in the absorption strength with azimuthal angles provide much stronger constraints on the intrinsic geometry of the Mg II absorption than the dependence on the inclination of the galaxies. In addition to the clear azimuthal dependence in the integrated Mg II absorption that we reported earlier in Bordoloi et al., we show that strong equivalent width Mg II absorbers (W{sub r} (2796) ≥ 0.3 Å) are also asymmetrically distributed in azimuth around their host galaxies: 72% of the absorbers in Kacprzak et al., and 100% of the close-in absorbers within 35 kpc of the center of their host galaxies, are located within 50° of the host galaxy's projected semi minor axis. It is shown that either composite models consisting of a simple bipolar component plus a spherical or disk component, or a single highly softened bipolar distribution, can well represent the azimuthal dependencies observed in both the stacked spectrum and quasar absorption-line data sets within 40 kpc. Simultaneously fitting both data sets, we find that in the composite model the bipolar cone has an opening angle of ∼100° (i.e., confined to within 50° of the disk axis) and contains about two-thirds of the total Mg II absorption in the system. The single softened cone model has an exponential fall off with azimuthal

  15. Phospholipid interactions in model membrane systems. II. Theory.

    PubMed Central

    Stigter, D; Mingins, J; Dill, K A

    1992-01-01

    -group model to semiconcentrated monolayers, in agreement with the surface potential data in the foregoing paper. PMID:1617141

  16. Double Higgs production at LHC, see-saw type-II and Georgi-Machacek model

    SciTech Connect

    Godunov, S. I. Vysotsky, M. I. Zhemchugov, E. V.

    2015-03-15

    The double Higgs production in the models with isospin-triplet scalars is studied. It is shown that in the see-saw type-II model, the mode with an intermediate heavy scalar, pp → H + X → 2h + X, may have the cross section that is comparable with that in the Standard Model. In the Georgi-Machacek model, this cross section could be much larger than in the Standard Model because the vacuum expectation value of the triplet can be large.

  17. Mathematical modeling of copper(II) ion inhibition on COD removal in an activated sludge unit.

    PubMed

    Pamukoglu, M Yunus; Kargi, Fikret

    2007-07-19

    A mathematical model was developed to describe the Cu(II) ion inhibition on chemical oxygen demand (COD) removal from synthetic wastewater containing 15 mg l(-1) Cu(II) in an activated sludge unit. Experimental data obtained at different sludge ages (5-30 days) and hydraulic residence times (HRT) (5-25 h) were used to determine the kinetic, stoichiometric and inhibition constants for the COD removal rate in the presence and absence of Cu(II) ions. The inhibition pattern was identified as non-competitive, since Cu(II) ion inhibitions were observed both on maximum specific substrate removal rate (k) and on the saturation constant (Ks) with the inhibition constants of 97 and 18 mg l(-1), respectively, indicating more pronounced inhibition on Ks. The growth yield coefficient (Y) decreased and the death rate constant (b) increased in the presence of Cu(II) ions due to copper ion toxicity on microbial growth with inhibition constants of 29 and 200 mg l(-1), respectively indicating more effective inhibition on the growth yield coefficient or higher maintenance requirements. The mathematical model with the predetermined kinetic constants was able to predict the system performance reasonably well especially at high HRT operations.

  18. Competitive sorption and selective sequence of Cu(II) and Ni(II) on montmorillonite: Batch, modeling, EPR and XAS studies

    NASA Astrophysics Data System (ADS)

    Yang, Shitong; Ren, Xuemei; Zhao, Guixia; Shi, Weiqun; Montavon, Gilles; Grambow, Bernd; Wang, Xiangke

    2015-10-01

    Heavy metal ions that leach from various industrial and agricultural processes are simultaneously present in the contaminated soil and water systems. The competitive sorption of these toxic metal ions on the natural soil components and sediments significantly influences their migration, bioavailability and ecotoxicity in the geochemical environment. In this study, the competitive sorption and selectivity order of Cu(II) and Ni(II) on montmorillonite are investigated by combining the batch experiments, X-ray diffraction (XRD), electron paramagnetic resonance (EPR), surface complexation modeling and X-ray Absorption Spectroscopy (XAS). The batch experimental data show that the coexisting Ni(II) exhibits a negligible influence on the sorption behavior of Cu(II), whereas the coexisting Cu(II) reduces the Ni(II) sorption percentage and changes the shape of the Ni(II) sorption isotherm. The sorption species of Cu(II) and Ni(II) on montmorillonite over the acidic and near-neutral pH range are well simulated by the surface complexation modeling. However, this model cannot identify the occurrence of surface nucleation and the co-precipitation processes at a highly alkaline pH. Based on the results of the EPR and XAS analyses, the microstructures of Cu(II) on montmorillonite are identified as the hydrated free Cu(II) ions at pH 5.0, inner-sphere surface complexes at pH 6.0 and the surface dimers/Cu(OH)2(s) precipitate at pH 8.0 in the single-solute and the binary-solute systems. For the Ni(II) sorption in the single-solute system, the formed microstructure varies from the hydrated free Ni(II) ions at the pH values of 5.0 and 6.0 to the inner-sphere surface complexes at pH 8.0. For the Ni(II) sorption in the binary-solute system, the coexisting Cu(II) induces the formation of the inner-sphere complexes at pH 6.0. In contrast, Ni(II) is adsorbed on montmorillonite via the formation of Ni phyllosilicate co-precipitate/α-Ni(OH)2(s) precipitate at pH 8.0. The selective sequence

  19. 78 FR 5765 - Wireline Competition Bureau Releases Connect America Phase II Cost Model Virtual Workshop...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-28

    ...] Wireline Competition Bureau Releases Connect America Phase II Cost Model Virtual Workshop Discussion Topics... Competition Bureau releases for discussion a number of virtual workshop topics related to the development and... comments. Virtual Workshop: In addition to the usual methods for filing electronic comments, the...

  20. Catalytic Oxygen Evolution by a Bioinorganic Model of the Photosystem II Oxygen-Evolving Complex

    ERIC Educational Resources Information Center

    Howard, Derrick L.; Tinoco, Arthur D.; Brudvig, Gary W.; Vrettos, John S.; Allen, Bertha Connie

    2005-01-01

    Bioinorganic models of the manganese Mn4 cluster are important not only as aids in understanding the structure and function of the oxygen-evolving complex (OEC), but also in developing artificial water-oxidation catalysts. The mechanism of water oxidation by photosystem II (PSII) is thought to involve the formation of a high-valent terminal Mn-oxo…

  1. A synthetic model for the oxygen-evolving complex in Sr(2+)-containing photosystem II.

    PubMed

    Chen, Changhui; Zhang, Chunxi; Dong, Hongxing; Zhao, Jingquan

    2014-08-25

    A novel heterometallic MnSr complex containing the Mn3SrO4 cuboidal moiety and all types of μ-O(2-) moieties observed in the oxygen-evolving complex (OEC) in Sr(2+)-containing photosystem II (PSII) has been synthesized and characterized, which provides a new synthetic model of the OEC.

  2. Curriculum Guides for Level I and Level II: National Manpower Model.

    ERIC Educational Resources Information Center

    National Inst. on Mental Retardation, Toronto (Ontario).

    Curriculum guides to levels I and II of the Canadian National Manpower Model, which elaborate on content originally presented in 1971, are provided for personnel training programs in the field of mental retardation and related handicapping areas. The guides are said to be based on a philosophy that demands society's acceptance of retarded and…

  3. Mathematical models and illustrative results for the RINGBEARER II monopole/dipole beam-propagation code

    SciTech Connect

    Chambers, F.W.; Masamitsu, J.A.; Lee, E.P.

    1982-05-24

    RINGBEARER II is a linearized monopole/dipole particle simulation code for studying intense relativistic electron beam propagation in gas. In this report the mathematical models utilized for beam particle dynamics and pinch field computation are delineated. Difficulties encountered in code operations and some remedies are discussed. Sample output is presented detailing the diagnostics and the methods of display and analysis utilized.

  4. Catalytic Oxygen Evolution by a Bioinorganic Model of the Photosystem II Oxygen-Evolving Complex

    ERIC Educational Resources Information Center

    Howard, Derrick L.; Tinoco, Arthur D.; Brudvig, Gary W.; Vrettos, John S.; Allen, Bertha Connie

    2005-01-01

    Bioinorganic models of the manganese Mn4 cluster are important not only as aids in understanding the structure and function of the oxygen-evolving complex (OEC), but also in developing artificial water-oxidation catalysts. The mechanism of water oxidation by photosystem II (PSII) is thought to involve the formation of a high-valent terminal Mn-oxo…

  5. A Parameter Study for Modeling Mg ii h and k Emission during Solar Flares

    NASA Astrophysics Data System (ADS)

    Rubio da Costa, Fatima; Kleint, Lucia

    2017-06-01

    Solar flares show highly unusual spectra in which the thermodynamic conditions of the solar atmosphere are encoded. Current models are unable to fully reproduce the spectroscopic flare observations, especially the single-peaked spectral profiles of the Mg ii h and k lines. We aim to understand the formation of the chromospheric and optically thick Mg ii h and k lines in flares through radiative transfer calculations. We take a flare atmosphere obtained from a simulation with the radiative hydrodynamic code RADYN as input for a radiative transfer modeling with the RH code. By iteratively changing this model atmosphere and varying thermodynamic parameters such as temperature, electron density, and velocity, we study their effects on the emergent intensity spectra. We reproduce the typical single-peaked Mg ii h and k flare spectral shape and approximate the intensity ratios to the subordinate Mg ii lines by increasing either densities, temperatures, or velocities at the line core formation height range. Additionally, by combining unresolved upflows and downflows up to ˜250 km s-1 within one resolution element, we reproduce the widely broadened line wings. While we cannot unambiguously determine which mechanism dominates in flares, future modeling efforts should investigate unresolved components, additional heat dissipation, larger velocities, and higher densities and combine the analysis of multiple spectral lines.

  6. A primer for biomedical scientists on how to execute model II linear regression analysis.

    PubMed

    Ludbrook, John

    2012-04-01

    1. There are two very different ways of executing linear regression analysis. One is Model I, when the x-values are fixed by the experimenter. The other is Model II, in which the x-values are free to vary and are subject to error. 2. I have received numerous complaints from biomedical scientists that they have great difficulty in executing Model II linear regression analysis. This may explain the results of a Google Scholar search, which showed that the authors of articles in journals of physiology, pharmacology and biochemistry rarely use Model II regression analysis. 3. I repeat my previous arguments in favour of using least products linear regression analysis for Model II regressions. I review three methods for executing ordinary least products (OLP) and weighted least products (WLP) regression analysis: (i) scientific calculator and/or computer spreadsheet; (ii) specific purpose computer programs; and (iii) general purpose computer programs. 4. Using a scientific calculator and/or computer spreadsheet, it is easy to obtain correct values for OLP slope and intercept, but the corresponding 95% confidence intervals (CI) are inaccurate. 5. Using specific purpose computer programs, the freeware computer program smatr gives the correct OLP regression coefficients and obtains 95% CI by bootstrapping. In addition, smatr can be used to compare the slopes of OLP lines. 6. When using general purpose computer programs, I recommend the commercial programs systat and Statistica for those who regularly undertake linear regression analysis and I give step-by-step instructions in the Supplementary Information as to how to use loss functions. © 2011 The Author. Clinical and Experimental Pharmacology and Physiology. © 2011 Blackwell Publishing Asia Pty Ltd.

  7. Community environmental education: three models of organization for PSD Set II. Final report

    SciTech Connect

    Burke, P.

    1980-06-01

    The study undertakes an examination of models of community environmental education relevant for PSD Set II. Issues of sufficient technical information, aspects of citizen participation, organizational theory, and politics are examined. Community environmental education is deemed to be feasible here, and three potential organizational models are presented: one focuses on the Cooperative Extension Service, one on regional planning bodies, and one on the community school network.

  8. On type II superstrings; The. sigma. model and compactification to D = 4

    SciTech Connect

    Castellani, L. ); D'Auria, R.; Franco, D. )

    1991-09-20

    This paper presents a geometric construction of the {sigma} model describing type II superstrings propagating on an arbitrary M{sub target}. Specializing the covering space of the internal target manifold to be the nine-dimensional group manifold SU(2){sup 3}, the authors discuss the massless vertices both in the (4 + 9)-dimensional {sigma} model and in the D = 4 superconformal theory, and show how they are related via dimensional reduction.

  9. Flight Model Development of Tokyo Tech Nano-Satellite Cute-1.7 + APD II

    NASA Astrophysics Data System (ADS)

    Ashida, Hiroki; Nishida, Junichi; Omagari, Kuniyuki; Fujiwara, Ken; Konda, Yasumi; Yamanaka, Tomio; Tanaka, Yohei; Maeno, Masaki; Fujihashi, Kota; Inagawa, Shinichi; Miura, Yoshiyuki; Matunaga, Saburo

    The Laboratory for Space Systems at the Tokyo Institute of Technology has developed the nano-satellite Cute-1.7+APD. The satellite was launched by JAXA M-V-8 rocket on February 22, 2006 and operated for about a month. A successor to the Cute-1.7+APD was developed and is named Cute-1.7+APD II. This new satellite is based on its predecessor but has some modifications. In this paper an overview of the Cute-1.7 series and flight model development of Cute-1.7+APD II are introduced.

  10. ESEEM Analysis of Multi-Histidine Cu(II)-Coordination in Model Complexes, Peptides, and Amyloid-β

    PubMed Central

    2015-01-01

    We validate the use of ESEEM to predict the number of 14N nuclei coupled to a Cu(II) ion by the use of model complexes and two small peptides with well-known Cu(II) coordination. We apply this method to gain new insight into less explored aspects of Cu(II) coordination in amyloid-β (Aβ). Aβ has two coordination modes of Cu(II) at physiological pH. A controversy has existed regarding the number of histidine residues coordinated to the Cu(II) ion in component II, which is dominant at high pH (∼8.7) values. Importantly, with an excess amount of Zn(II) ions, as is the case in brain tissues affected by Alzheimer’s disease, component II becomes the dominant coordination mode, as Zn(II) selectively substitutes component I bound to Cu(II). We confirm that component II only contains single histidine coordination, using ESEEM and set of model complexes. The ESEEM experiments carried out on systematically 15N-labeled peptides reveal that, in component II, His 13 and His 14 are more favored as equatorial ligands compared to His 6. Revealing molecular level details of subcomponents in metal ion coordination is critical in understanding the role of metal ions in Alzheimer’s disease etiology. PMID:25014537

  11. Cosmological Parameter Uncertainties from SALT-II Type Ia Supernova Light Curve Models

    SciTech Connect

    Mosher, J.; Guy, J.; Kessler, R.; Astier, P.; Marriner, J.; Betoule, M.; Sako, M.; El-Hage, P.; Biswas, R.; Pain, R.; Kuhlmann, S.; Regnault, N.; Frieman, J. A.; Schneider, D. P.

    2014-08-29

    We use simulated type Ia supernova (SN Ia) samples, including both photometry and spectra, to perform the first direct validation of cosmology analysis using the SALT-II light curve model. This validation includes residuals from the light curve training process, systematic biases in SN Ia distance measurements, and a bias on the dark energy equation of state parameter w. Using the SN-analysis package SNANA, we simulate and analyze realistic samples corresponding to the data samples used in the SNLS3 analysis: ~120 low-redshift (z < 0.1) SNe Ia, ~255 Sloan Digital Sky Survey SNe Ia (z < 0.4), and ~290 SNLS SNe Ia (z ≤ 1). To probe systematic uncertainties in detail, we vary the input spectral model, the model of intrinsic scatter, and the smoothing (i.e., regularization) parameters used during the SALT-II model training. Using realistic intrinsic scatter models results in a slight bias in the ultraviolet portion of the trained SALT-II model, and w biases (w (input) – w (recovered)) ranging from –0.005 ± 0.012 to –0.024 ± 0.010. These biases are indistinguishable from each other within the uncertainty, the average bias on w is –0.014 ± 0.007.

  12. Cosmological parameter uncertainties from SALT-II type Ia supernova light curve models

    SciTech Connect

    Mosher, J.; Sako, M.; Guy, J.; Astier, P.; Betoule, M.; El-Hage, P.; Pain, R.; Regnault, N.; Marriner, J.; Biswas, R.; Kuhlmann, S.; Schneider, D. P.

    2014-09-20

    We use simulated type Ia supernova (SN Ia) samples, including both photometry and spectra, to perform the first direct validation of cosmology analysis using the SALT-II light curve model. This validation includes residuals from the light curve training process, systematic biases in SN Ia distance measurements, and a bias on the dark energy equation of state parameter w. Using the SN-analysis package SNANA, we simulate and analyze realistic samples corresponding to the data samples used in the SNLS3 analysis: ∼120 low-redshift (z < 0.1) SNe Ia, ∼255 Sloan Digital Sky Survey SNe Ia (z < 0.4), and ∼290 SNLS SNe Ia (z ≤ 1). To probe systematic uncertainties in detail, we vary the input spectral model, the model of intrinsic scatter, and the smoothing (i.e., regularization) parameters used during the SALT-II model training. Using realistic intrinsic scatter models results in a slight bias in the ultraviolet portion of the trained SALT-II model, and w biases (w {sub input} – w {sub recovered}) ranging from –0.005 ± 0.012 to –0.024 ± 0.010. These biases are indistinguishable from each other within the uncertainty; the average bias on w is –0.014 ± 0.007.

  13. Two Higgs doublet model of type II facing flavor physics data

    SciTech Connect

    Deschamps, Olivier; Monteil, Stephane; Niess, Valentin; Descotes-Genon, Sebastien; T'Jampens, Stephane; Tisserand, Vincent

    2010-10-01

    We discuss tests of the charged Higgs sector of the two Higgs doublet model (2HDM) of type II in the light of recent flavor physics data. Particular attention is paid to recent measurement of purely leptonic decays of heavy-light mesons, which depart more or less significantly from the standard model (SM) predictions. We derive constraints on the parameters of the 2HDM type II from leptonic and semileptonic {Delta}F=1 decays as well as loop processes (b{yields}s{gamma}, BB mixing, or Z{yields}bb) sensitive to charged Higgs contributions. The outcome of this work is that while 2HDM type II can fit the individual observable through fine-tuning schemes, in a combined analysis it does not perform better than the standard model by favoring a decoupling solution. Assuming that 2HDM type II is realized in nature, constraints on its parameters (m{sub H}{sup +} and tan{beta}) are derived. A limit on the charged Higgs mass m{sub H}{sup +}>316 GeV at 95% CL is obtained irrespective of the value of tan{beta}. This limit is dominated by the b{yields}s{gamma} branching ratio measurement. All results have been obtained with the CKMfitter analysis package, featuring the frequentist statistical approach Rfit to handle theoretical uncertainties.

  14. Modeling the effect of temperature on adsorption of lead(II) and zinc(II) onto goethite at constant pH

    SciTech Connect

    Rodda, D.P.; Johnson, B.B.; Wells, J.D.

    1996-12-25

    The influence of temperature and adsorbate concentration on the sorption of Zn(II) and Pb(II) by goethite was studied at fixed pH. Proton stoichiometry, measured by direct titration, was found to depend on the identity of the metal ion, the pH, and the temperature. For Zn(II) the proton stoichiometry ranged from 1.55 at pH 6.5 and 10 C to 1.95 at pH 7.5 and 70 C, while for Pb(II) at pH 5.50 the value varied from 1.05 at 10 C to 1.4 at 70 C. Three adsorption models--the Langmuir two-site model, the surface precipitation model of Farley, Dzombak, and Morel (FDM), and the BET model--were applied to the data, and the fitted parameters were used to determine the enthalpy and entropy of adsorption. Although the models assume rather different equilibrium constants, the estimated enthalpies of adsorption were all positive, between 4 and 30 kJ/mol. There was also fair agreement between the various estimates of the adsorption capacities. However, the models yield very different estimates of entropies of adsorption, these being positive (and generally in the range 100 to 160 J/K mol) for the Langmuir and BET models but negative (in the range {minus}80 to {minus}160 J/K mol) for the FDM model.

  15. Controlling FAMA by the Ptolemy II model of ion beam transport

    NASA Astrophysics Data System (ADS)

    Balvanović, R.; Rađenović, B.; Beličev, P.; Nešković, N.

    2009-08-01

    FAMA is a facility for modification and analysis of materials with ion beams. Due to the wide range of ion beams and energies used in the facility and its future expansion, the need has arisen for faster tuning of ion beams transport control parameters. With this aim, a new approach to modeling ion-beam transport system was developed, based on the Ptolemy II modeling and design framework. A model in Ptolemy II is a hierarchical aggregation of components called actors, which communicate with other actors using tokens, or pieces of data. Each ion optical element is modeled by a composite actor implementing beam matrix transformation function, while tokens carry beam matrix data. A basic library of models of typical ion optical elements is developed, and a complex model of FAMA ion beam transport system is hierarchically integrated with bottom-up approach. The model is extended to include control functions. The developed model is modular, flexible and extensible. The results obtained by simulation on the model demonstrate easy and efficient tuning of beam line control parameters. Fine tuning of control parameters, due to uncertainties inherent to modeling, still has to be performed on-line.

  16. The Jena Diversity Model: Towards a Richer Representation of the Terrestrial Biosphere for Earth System Modelling

    NASA Astrophysics Data System (ADS)

    Pavlick, R.; Reu, B.; Bohn, K.; Dyke, J.; Kleidon, A.

    2010-12-01

    The terrestrial biosphere is a complex, self-organizing system which is continually both adapting to and altering its global environment. It also exhibits a vast diversity of vegetation forms and functioning. However, the terrestrial biosphere components within current state-of-the-art Earth System Models abstract this diversity in to a handful of relatively static plant functional types. These coarse and static representations of functional diversity might contribute to overly pessimistic projections regarding terrestrial ecosystem responses to scenarios of global change (e.g. Amazonian and boreal forest diebacks). In the Jena Diversity (JeDi) model, we introduce a new approach to vegetation modelling with a richer representation of functional diversity, based not on plant functional types, but on unavoidable plant ecophysiological trade-offs, which we hypothesize should be more stable in time. The JeDi model tests a large number of plant growth strategies. Each growth strategy is simulated using a set of randomly generated parameter values, which characterize its functioning in terms of carbon allocation, ecophysiology, and phenology, which are then linked to the growing conditions at the land surface. The model is constructed in such a way that these parameters inherently lead to ecophysiological trade-offs, which determine whether a growth strategy is able to survive and reproduce under the prevalent climatic conditions. Kleidon and Mooney (2000) demonstrated that this approach is capable of reproducing the geographic distribution of species richness. More recently, we have shown the JeDi model can explain other biogeographical phenomena including the present-day global pattern of biomes (Reu et al., accepted), ecosystem evenness (Kleidon et al. 2009), and possible mechanisms for biome shifts and biodiversity changes under scenarios of global warming (Reu et al., submitted). We have also evaluated the simulated biogeochemical fluxes from JeDi against a variety

  17. Development and comparison of a TOPAZ-II system model with experimental data

    SciTech Connect

    Paramonov, D.V.; El-Genk, M.S. . Inst. for Space Nuclear Power Studies)

    1994-11-01

    An integrated model of the TOPAZ-II space nuclear reactor system is developed and compared with measurements from the TOPAZ-II, V-71 unit tests. For a given reactor thermal power, the model calculates the coolant flow rate, temperature, and pressure throughout the system; load electric power; and overall system efficiency. Model predictions showed good agreement with the experimental data. The calculated coolant temperatures and pressure are within 15 K (< 2%) and 12% of the measurements, respectively. Analysis showed that at the nominal operating thermal power of the system (115 kW), and NaK coolant is highly subcooled. The largest subcooling of 365 K occurs at the exit of the electromagnetic pump, where coolant pressure is highest, and the lowest subcooling of 275 K occurs at the exit of the reactor core, where coolant temperature is highest.

  18. 78 FR 76791 - Availability of Version 4.0 of the Connect America Fund Phase II Cost Model; Adopting Current...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-19

    ... COMMISSION 47 CFR Part 54 Availability of Version 4.0 of the Connect America Fund Phase II Cost Model... the Connect America Cost Model (CAM v4.0) will be available shortly. The Bureau seeks comment on... cost in price cap areas for implementing Connect America Phase II. DATES: Comments are due on or before...

  19. Resonance Raman spectra of iron(III)-, copper(II)-, cobalt(III)-, and manganese(III)-transferrins and of bis(2,4,6-trichlorophenolato)diimidazolecopper(II) monohydrate, a possible model for copper(II) binding to transferrins.

    PubMed

    Tomimatsu, Y; Kint, S; Scherer, J R

    1976-11-02

    Fe(III), Cu(II), Co(III), and Mn(III) complexes of ovo- and human serum transferrins show resonance enhanced Raman bands near 1600, 1500, 1270, and 1170 cm-1 upon excitation with laser frequencies which fall within the visible absorption bands of those metalloproteins. Comparison of the visible absorption and resonance Raman spectra of the Cu(II)-transferrin complexes with those for the Cu(II) model compound, bis(2,4,6-trichlorophenolato)diimidazolecopper(II) monohydrate, indicates that the resonance Raman bands are due to enhancement of phenolic vibrational modes. For the model (Cu(II) compound, a normal coordinate analysis was used to aid our assignment of the observed resonance bands at 1562, 1463, 1311, and 1122 cm-1 to A1 vibrational modes of the 2,4,6-trichlorophenolato moiety. These assignments are consistent with those made for Cu(II)-transferrins. The latter assignments were based upon calculated A1 frequencies for p-methylphenol (Cummings, D.L., and Wood, J.L. (1974), J. Mol. Struct. 20, 1). The wavelength shifts in the resonance bands for the model compound from those for Cu(II)-transferrins are due to the influence of the chloro substituents on the planar vibrations of phenol. These results clearly identify tyrosine as a ligand in copper binding to transferrins.

  20. Schizosaccharomyces pombe and its Ni(II)-insensitive mutant GA1 in Ni(II) uptake from aqueous solutions: a biodynamic model.

    PubMed

    Sayar, Nihat Alpagu; Durmaz-Sam, Selcen; Kazan, Dilek; Sayar, Ahmet Alp

    2014-08-01

    In the present study, Ni(II) uptake from aqueous solution by living cells of the Schizosaccharomyces pombe haploid 972 with h (-) mating type and a Ni(II)-insensitive mutant GA1 derived from 972 was investigated at various initial glucose and Ni(II) concentrations. A biodynamic model was developed to predict the unsteady and steady-state phases of the uptake process. Gompertz growth and uptake process parameters were optimized to predict the maximum growth rate μ m and the process metric C r, the remaining Ni(II) content in the aqueous solution. The simulated overall metal uptake values were found to be in acceptable agreement with experimental results. The model validation was done through regression statistics and uncertainty and sensitivity analyses. To gain insight into the phenomenon of Ni(II) uptake by wild-type and mutant S. pombe, probable active and passive metal transport mechanisms in yeast cells were discussed in view of the simulation results. The present work revealed the potential of mutant GA1 to remove Ni(II) cations from aqueous media. The results obtained provided new insights for understanding the combined effect of biosorption and bioaccumulation processes for metal removal and offered a possibility for the use of growing mutant S. pombe cell in bioremediation.

  1. Mn(II) and Cu(II) complexes of a bidentate Schiff's base ligand: spectral, thermal, molecular modelling and mycological studies.

    PubMed

    Tyagi, Monika; Chandra, Sulekh; Tyagi, Prateek

    2014-01-03

    Complexes of manganese(II) and copper(II) of general composition M(L)2X2 have been synthesized [L=2-acetyl thiophene thiosemicarbazone and X=Cl(-) and NO3(-)]. The elemental analysis, molar conductance measurements, magnetic susceptibility measurements, mass, IR, UV, NMR and EPR spectral studies of the compounds led to the conclusion that the ligand acts as a bidentate manner. The Schiff's base ligand forms hexacoordinated complexes having octahedral geometry for Mn(II) and tetragonal geometry for Cu(II) complexes. The thermal studies suggested that the complexes are more stable as compared to ligand. In molecular modelling the geometries of Schiff's base and metal complexes were fully optimized with respect to the energy using the 6-31g(d,p) basis set. The mycological studies of the compounds were examined against the plant pathogenic fungi i.e. Rhizoctonia bataticola, Macrophomina phaseolina, Fusarium odum.

  2. Mn(II) and Cu(II) complexes of a bidentate Schiff's base ligand: Spectral, thermal, molecular modelling and mycological studies

    NASA Astrophysics Data System (ADS)

    Tyagi, Monika; Chandra, Sulekh; Tyagi, Prateek

    2014-01-01

    Complexes of manganese(II) and copper(II) of general composition M(L)2X2 have been synthesized [L = 2-acetyl thiophene thiosemicarbazone and X = Cl- and NO3-]. The elemental analysis, molar conductance measurements, magnetic susceptibility measurements, mass, IR, UV, NMR and EPR spectral studies of the compounds led to the conclusion that the ligand acts as a bidentate manner. The Schiff's base ligand forms hexacoordinated complexes having octahedral geometry for Mn(II) and tetragonal geometry for Cu(II) complexes. The thermal studies suggested that the complexes are more stable as compared to ligand. In molecular modelling the geometries of Schiff's base and metal complexes were fully optimized with respect to the energy using the 6-31g(d,p) basis set. The mycological studies of the compounds were examined against the plant pathogenic fungi i.e. Rhizoctonia bataticola, Macrophomina phaseolina, Fusarium odum.

  3. Reactive Transport Modeling of Microbe-mediated Fe (II) Oxidation for Enhanced Oil Recovery

    NASA Astrophysics Data System (ADS)

    Surasani, V.; Li, L.

    2011-12-01

    Microbially Enhanced Oil Recovery (MEOR) aims to improve the recovery of entrapped heavy oil in depleted reservoirs using microbe-based technology. Reservoir ecosystems often contain diverse microbial communities those can interact with subsurface fluids and minerals through a network of nutrients and energy fluxes. Microbe-mediated reactions products include gases, biosurfactants, biopolymers those can alter the properties of oil and interfacial interactions between oil, brine, and rocks. In addition, the produced biomass and mineral precipitates can change the reservoir permeability profile and increase sweeping efficiency. Under subsurface conditions, the injection of nitrate and Fe (II) as the electron acceptor and donor allows bacteria to grow. The reaction products include minerals such as Fe(OH)3 and nitrogen containing gases. These reaction products can have large impact on oil and reservoir properties and can enhance the recovery of trapped oil. This work aims to understand the Fe(II) oxidation by nitrate under conditions relevant to MEOR. Reactive transport modeling is used to simulate the fluid flow, transport, and reactions involved in this process. Here we developed a complex reactive network for microbial mediated nitrate-dependent Fe (II) oxidation that involves both thermodynamic controlled aqueous reactions and kinetic controlled Fe (II) mineral reaction. Reactive transport modeling is used to understand and quantify the coupling between flow, transport, and reaction processes. Our results identify key parameter controls those are important for the alteration of permeability profile under field conditions.

  4. Application of Bayesian hierarchical models for phase I/II clinical trials in oncology.

    PubMed

    Yada, Shinjo; Hamada, Chikuma

    2017-03-01

    Treatment during cancer clinical trials sometimes involves the combination of multiple drugs. In addition, in recent years there has been a trend toward phase I/II trials in which a phase I and a phase II trial are combined into a single trial to accelerate drug development. Methods for the seamless combination of phases I and II parts are currently under investigation. In the phase II part, adaptive randomization on the basis of patient efficacy outcomes allocates more patients to the dose combinations considered to have higher efficacy. Patient toxicity outcomes are used for determining admissibility to each dose combination and are not used for selection of the dose combination itself. In cases where the objective is not to find the optimum dose combination solely for efficacy but regarding both toxicity and efficacy, the need exists to allocate patients to dose combinations with consideration of the balance of existing trade-offs between toxicity and efficacy. We propose a Bayesian hierarchical model and an adaptive randomization with consideration for the relationship with toxicity and efficacy. Using the toxicity and efficacy outcomes of patients, the Bayesian hierarchical model is used to estimate the toxicity probability and efficacy probability in each of the dose combinations. Here, we use Bayesian moving-reference adaptive randomization on the basis of desirability computed from the obtained estimator. Computer simulations suggest that the proposed method will likely recommend a higher percentage of target dose combinations than a previously proposed method.

  5. An Angular Overlap Model for Cu(II) Ion in the AMOEBA Polarizable Force Field.

    PubMed

    Xiang, Jin Yu; Ponder, Jay W

    2014-01-01

    An extensible polarizable force field for transition metal ion was developed based on AMOEBA and the angular overlap model (AOM) with consistent treatment of electrostatics for all atoms. Parameters were obtained by fitting molecular mechanics (MM) energies to various ab initio gas-phase calculations. The results of parameterization were presented for copper (II) ion ligated to water and model fragments of amino acid residues involved in the copper binding sites of type 1 copper proteins. Molecular dynamics (MD) simulations were performed on aqueous copper (II) ion at various temperatures, as well as plastocyanin (1AG6) and azurin (1DYZ). Results demonstrated that the AMOEBA-AOM significantly improves the accuracy of classical MM in a number of test cases when compared to ab initio calculations. The Jahn-Teller distortion for hexa-aqua copper (II) complex was handled automatically without specifically designating axial and in-plane ligands. Analyses of MD trajectories resulted in a 6-coordination first solvation shell for aqueous copper (II) ion and a 1.8ns average residence time of water molecules. The ensemble average geometries of 1AG6 and 1DYZ copper binding sites were in general agreement with X-ray and previous computational studies.

  6. [A model of photosystem II for the analysis of a fast fluorescence rise in plant leaves].

    PubMed

    Beliaeva, N E; Bulychev, A A; Riznichenko, G Iu; Rubin, A B

    2011-01-01

    The polyphasic patterns of fluorescence induction rise in pea leaves in vivo and after the treatment with ionophores have been studied using a plant efficiency analyzer. To analyze in detail photosystem II (PS II) electron transfer processes, an extended PS II model was applied, which included the sums of exponential functions to specify explicitly the light-driven formation of the transmembrane electric potential (delta psi(t)) as well as pH in the lumen (pHL(t)) and stroma (pHs(t)). PS II model parameters and numerical coefficients in delta psi(t), and pHs(t) were evaluated to fit fluorescence induction data for different experimental conditions: leaf in vivo or after ionophore treatment at low or high light intensity. The model imitated changes in the pattern of fluorescence induction rise due to the elimination of transmembrane potential in the presence of ionophores, when delta psi = 0 and pHL(t), pHS(t) altered to small extent relative to control values in vivo, with maximum delta psi(t) approximately 90 MB and delta psi(t) approximately 40 MB, for the stationary state at deltapH aproximately equal to 1.8. As the light intensity was increased from 300 to 1200 micromol x m(-2) x s(-1), the heat dissipation rate constants increased threefold for nonradiative recombination of P680+Phe- and by approximately 30% for P680+Q(A)-. The parameters delta psi, pH(S) and pH(L) were analyzed as factors of PS II redox state populations and fluorescence yield. The kinetic mechanism of qE quenching is discussed, which is related with light induced pH(L) lumen acidification, when Q(A)- and P680+ recombination probability increases to regulate the QA reduction.

  7. Seizure modeling of Pb(II) and Cd(II) from aqueous solution by chemically modified sugarcane bagasse fly ash: isotherms, kinetics, and column study.

    PubMed

    Shah, Bhavna; Mistry, Chirag; Shah, Ajay

    2013-04-01

    Heavy metal pollution is a common environmental problem all over the world. The purpose of the research is to examine the applicability of bagasse fly ash (BFA)-an agricultural waste of sugar industry used for the synthesis of zeolitic material. The zeolitic material are used for the uptake of Pb(II) and Cd(II) heavy metal. Bagasse fly ash is used as a native material for the synthesis of zeolitic materials by conventional hydrothermal treatment without (conventional zeolitic bagasse fly ash (CZBFA)) and with electrolyte (conventional zeolitic bagasse fly ash in electrolyte media (ECZBFA)) media. Heavy metal ions Pb(II) and Cd(II) were successfully seized from aqueous media using these synthesized zeolitic materials. In this study, the zeolitic materials were well characterized by different instrumental methods such as Brunauer-Emmett-Teller, XRF, Fourier transform infrared spectroscopy, powder X-ray diffraction, and scanning electron microscopic microphotographs. The presence of analcime, phillipsite, and zeolite P in adsorbents confirms successful conversion of native BFA into zeolitic materials. Seizure modeling of Pb(II) and Cd(II) was achieved by batch sorption experiments, isotherms, and kinetic studies. These data were used to compare and evaluate the zeolitic materials as potential sorbents for the uptake of heavy metal ions from an aqueous media. The Langmuir isotherm correlation coefficient parameters best fit the equilibrium data which indicate the physical sorption. Pseudo-second-order and intra-particle diffusion model matches best which indicates that the rate of sorption was controlled by film diffusion. The column studies were performed for the practical function of sorbents, and breakthrough curves were obtained, which revealed higher sorption capacity as compared to batch method. Synthesized zeolitic material (CZBFA and ECZBFA), a low-cost sorbent, was proven as potential sorbent for the uptake of Pb(II) and Cd(II) heavy metal ions.

  8. A dynamical model for FR II type radio sources with terminated jet activity

    NASA Astrophysics Data System (ADS)

    Kuligowska, Elżbieta

    2017-02-01

    Context. The extension of the KDA analytical model of FR II-type source evolution originally assuming a continuum injection process in the jet-IGM interaction towards a case of the jet's termination is presented and briefly discussed. Aims: The dynamical evolution of FR II-type sources predicted with this extended model, hereafter referred to as KDA EXT, and its application to the chosen radio sources. Methods: Following the classical approach based on the source's continuous injection and self-similarity, I propose the effective formulae describing the length and luminosity evolution of the lobes during an absence of the jet flow, and present the resulting diagrams for the characteristics mentioned. Results: Using an algorithm based on the numerical integration of a modified formula for jet power, the KDA EXT model is fitted to three radio galaxies. Their predicted spectra are then compared to the observed spectra, proving that these fits are better than the best spectral fit provided by the original KDA model of the FR II-type sources dynamical evolution.

  9. Constructing kinetic models to elucidate structural dynamics of a complete RNA polymerase II elongation cycle

    NASA Astrophysics Data System (ADS)

    Yu, Jin; Da, Lin-Tai; Huang, Xuhui

    2015-02-01

    The RNA polymerase II elongation is central in eukaryotic transcription. Although multiple intermediates of the elongation complex have been identified, the dynamical mechanisms remain elusive or controversial. Here we build a structure-based kinetic model of a full elongation cycle of polymerase II, taking into account transition rates and conformational changes characterized from both single molecule experimental studies and computational simulations at atomistic scale. Our model suggests a force-dependent slow transition detected in the single molecule experiments corresponds to an essential conformational change of a trigger loop (TL) opening prior to the polymerase translocation. The analyses on mutant study of E1103G and on potential sequence effects of the translocation substantiate this proposal. Our model also investigates another slow transition detected in the transcription elongation cycle which is independent of mechanical force. If this force-independent slow transition happens as the TL gradually closes upon NTP binding, the analyses indicate that the binding affinity of NTP to the polymerase has to be sufficiently high. Otherwise, one infers that the slow transition happens pre-catalytically but after the TL closing. Accordingly, accurate determination of intrinsic properties of NTP binding is demanded for an improved characterization of the polymerase elongation. Overall, the study provides a working model of the polymerase II elongation under a generic Brownian ratchet mechanism, with most essential structural transition and functional kinetics elucidated.

  10. SAGE II aerosol data validation based on retrieved aerosol model size distribution from SAGE II aerosol measurements

    NASA Technical Reports Server (NTRS)

    Wang, Pi-Huan; Mccormick, M. P.; Mcmaster, L. R.; Chu, W. P.; Swissler, T. J.; Osborn, M. T.; Russell, P. B.; Oberbeck, V. R.; Livingston, J.; Rosen, J. M.

    1989-01-01

    Consideration is given to aerosol correlative measurements experiments for the Stratospheric Aerosol and Gas Experiment (SAGE) II, conducted between November 1984 and July 1986. The correlative measurements were taken with an impactor/laser probe, a dustsonde, and an airborne 36-cm lidar system. The primary aerosol quantities measured by the ground-based instruments are compared with those calculated from the aerosol size distributions from SAGE II aerosol extinction measurements. Good agreement is found between the two sets of measurements.

  11. Longitudinal evaluation of dental arch asymmetry in Class II subdivision malocclusion with 3-dimensional digital models.

    PubMed

    Veli, Ilknur; Yuksel, Burcin; Uysal, Tancan

    2014-06-01

    Class II subdivision malocclusions with their asymmetric occlusal relationships often pose treatment difficulties. The aim of this study was to evaluate the longitudinal changes of dental arch asymmetry in untreated subjects with Class II subdivision malocclusion. From 706 files from the University of Michigan Growth Study, longitudinal records of 17 untreated subjects with Class II subdivision malocclusion were included this study. Dental arch changes at 3 consecutive longitudinal intervals, defined by the cervical vertebral maturation method, were analyzed on digital dental models. The average ages of the subjects were 12.4, 15.1, and 19.1 years at the 3 time periods, respectively. Maxillary and mandibular reference lines were constructed and used for the intra-arch asymmetry measurements. The Friedman test and analysis of variance with repeated measures were used to determine dental arch asymmetries at the P <0.05 level. All subjects were found to have a type 1 Class II subdivision malocclusion characterized by distal positioning of the mandibular first molar on the Class II side. No statistically significant intra-arch asymmetry changes were found for the maxillary and mandibular dental arches in any time period. Between the baseline and the final follow-up, the data indicated decreases in maxillary and mandibular intercanine arch widths and arch lengths symmetrically. The results of this study indicate that the dental arch asymmetry in patients with Class II subdivision malocclusions did not improve or worsen with growth. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  12. Structural Model of RNA Polymerase II Elongation Complex with Complete Transcription Bubble Reveals NTP Entry Routes

    PubMed Central

    Zhang, Lu; Silva, Daniel-Adriano; Pardo-Avila, Fátima; Wang, Dong; Huang, Xuhui

    2015-01-01

    The RNA polymerase II (Pol II) is a eukaryotic enzyme that catalyzes the synthesis of the messenger RNA using a DNA template. Despite numerous biochemical and biophysical studies, it remains elusive whether the “secondary channel” is the only route for NTP to reach the active site of the enzyme or if the “main channel” could be an alternative. On this regard, crystallographic structures of Pol II have been extremely useful to understand the structural basis of transcription, however, the conformation of the unpaired non-template DNA part of the full transcription bubble (TB) is still unknown. Since diffusion routes of the nucleoside triphosphate (NTP) substrate through the main channel might overlap with the TB region, gaining structural information of the full TB is critical for a complete understanding of Pol II transcription process. In this study, we have built a structural model of Pol II with a complete transcription bubble based on multiple sources of existing structural data and used Molecular Dynamics (MD) simulations together with structural analysis to shed light on NTP entry pathways. Interestingly, we found that although both channels have enough space to allow NTP loading, the percentage of MD conformations containing enough space for NTP loading through the secondary channel is twice higher than that of the main channel. Further energetic study based on MD simulations with NTP loaded in the channels has revealed that the diffusion of the NTP through the main channel is greatly disfavored by electrostatic repulsion between the NTP and the highly negatively charged backbones of nucleotides in the non-template DNA strand. Taken together, our results suggest that the secondary channel is the major route for NTP entry during Pol II transcription. PMID:26134169

  13. Structural Model of RNA Polymerase II Elongation Complex with Complete Transcription Bubble Reveals NTP Entry Routes.

    PubMed

    Zhang, Lu; Silva, Daniel-Adriano; Pardo-Avila, Fátima; Wang, Dong; Huang, Xuhui

    2015-07-01

    The RNA polymerase II (Pol II) is a eukaryotic enzyme that catalyzes the synthesis of the messenger RNA using a DNA template. Despite numerous biochemical and biophysical studies, it remains elusive whether the "secondary channel" is the only route for NTP to reach the active site of the enzyme or if the "main channel" could be an alternative. On this regard, crystallographic structures of Pol II have been extremely useful to understand the structural basis of transcription, however, the conformation of the unpaired non-template DNA part of the full transcription bubble (TB) is still unknown. Since diffusion routes of the nucleoside triphosphate (NTP) substrate through the main channel might overlap with the TB region, gaining structural information of the full TB is critical for a complete understanding of Pol II transcription process. In this study, we have built a structural model of Pol II with a complete transcription bubble based on multiple sources of existing structural data and used Molecular Dynamics (MD) simulations together with structural analysis to shed light on NTP entry pathways. Interestingly, we found that although both channels have enough space to allow NTP loading, the percentage of MD conformations containing enough space for NTP loading through the secondary channel is twice higher than that of the main channel. Further energetic study based on MD simulations with NTP loaded in the channels has revealed that the diffusion of the NTP through the main channel is greatly disfavored by electrostatic repulsion between the NTP and the highly negatively charged backbones of nucleotides in the non-template DNA strand. Taken together, our results suggest that the secondary channel is the major route for NTP entry during Pol II transcription.

  14. Paraquat-induced injury of type II alveolar cells. An in vitro model of oxidant injury

    SciTech Connect

    Skillrud, D.M.; Martin, W.J.

    1984-06-01

    Paraquat, a widely used herbicide, causes severe, often fatal lung damage. In vivo studies suggest the alveolar epithelial cells (types I and II) are specific targets of paraquat toxicity. This study used /sup 51/Cr-labeled type II cells to demonstrate that paraquat (10-5 M) resulted in type II cell injury in vitro, independent of interacting immune effector agents. With /sup 51/Cr release expressed as the cytotoxic index (Cl), type II cell injury was found to accelerate with increasing paraquat concentrations (10(-5) M, 10(-4) M, and 10(-3) M, resulting in a Cl of 12.5 +/- 2.2, 22.8 +/- 1.8, and 35.1 +/- 1.9, respectively). Paraquat-induced cytotoxicity (10(-4) M, with a Cl of 22.8 +/- 1.8) was effectively reduced by catalase 1,100 U/ml (Cl 8.0 +/- 3.2, p less than 0.001), superoxide dismutase, 300 U/ml (Cl 17.4 +/- 1.7, p less than 0.05), alpha tocopherol, 10 micrograms/ml (Cl 17.8 +/- 1.6, p less than 0.05). Paraquat toxicity (10(-3) M) was potentiated in the presence of 95% O2 with an increase in Cl from 31.1 +/- 1.7 to 36.4 +/- 2.3 (p less than 0.05). Paraquat-induced type II cell injury was noted as early as 4 h incubation by electron microscopic evidence of swelling of mitochondrial cristae and dispersion of nuclear chromatin. Thus, this in vitro model indicates that paraquat-induced type II cell injury can be quantified, confirmed by morphologic ultrastructural changes, significantly reduced by antioxidants, and potentiated by hyperoxia.

  15. Angiotensin II, hypertension, and angiotensin II receptor antagonism: Roles in the behavioural and brain pathology of a mouse model of Alzheimer's disease.

    PubMed

    Wiesmann, Maximilian; Roelofs, Monica; van der Lugt, Robert; Heerschap, Arend; Kiliaan, Amanda J; Claassen, Jurgen Ahr

    2016-01-01

    Elevated angiotensin II causes hypertension and contributes to Alzheimer's disease by affecting cerebral blood flow. Angiotensin II receptor blockers may provide candidates to reduce (vascular) risk factors for Alzheimer's disease. We studied effects of two months of angiotensin II-induced hypertension on systolic blood pressure, and treatment with the angiotensin II receptor blockers, eprosartan mesylate, after one month of induced hypertension in wild-type C57bl/6j and AβPPswe/PS1ΔE9 (AβPP/PS1/Alzheimer's disease) mice. AβPP/PS1 showed higher systolic blood pressure than wild-type. Subsequent eprosartan mesylate treatment restored this elevated systolic blood pressure in all mice. Functional connectivity was decreased in angiotensin II-infused Alzheimer's disease and wild-type mice, and only 12 months of Alzheimer's disease mice showed impaired cerebral blood flow. Only angiotensin II-infused Alzheimer's disease mice exhibited decreased spatial learning in the Morris water maze. Altogether, angiotensin II-induced hypertension not only exacerbated Alzheimer's disease-like pathological changes such as impairment of cerebral blood flow, functional connectivity, and cognition only in Alzheimer's disease model mice, but it also induced decreased functional connectivity in wild-type mice. However, we could not detect hypertension-induced overexpression of Aβ nor increased neuroinflammation. Our findings suggest a link between midlife hypertension, decreased cerebral hemodynamics and connectivity in an Alzheimer's disease mouse model. Eprosartan mesylate treatment restored and beneficially affected cerebral blood flow and connectivity. This model could be used to investigate prevention/treatment strategies in early Alzheimer's disease.

  16. Relaxin Treatment in an Ang-II-Based Transgenic Preeclamptic-Rat Model

    PubMed Central

    Haase, Nadine; Golic, Michaela; Herse, Florian; Rugor, Julianna; Linz, Dominik; Solano, Maria Emilia; Müller, Dominik N.; Dechend, Ralf

    2016-01-01

    Relaxin is a peptide related to pregnancy that induces nitric oxide-related and gelatinase-related effects, allowing vasodilation and pregnancy-related adjustments permitting parturition to occur. Relaxin controls the hemodynamic and renovascular adaptive changes that occur during pregnancy. Interest has evolved regarding relaxin and a therapeutic principle in preeclampsia and heart failure. Preeclampsia is a pregnancy disorder, featuring hypertension, proteinuria and placental anomalies. We investigated relaxin in an established transgenic rat model of preeclampsia, where the phenotype is induced by angiotensin (Ang)-II production in mid pregnancy. We gave recombinant relaxin to preeclamtic rats at day 9 of gestation. Hypertension and proteinuria was not ameliorated after relaxin administration. Intrauterine growth retardation of the fetus was unaltered by relaxin. Heart-rate responses and relaxin levels documented drug effects. In this Ang-II-based model of preeclampsia, we could not show a salubrious effect on preeclampsia. PMID:26963382

  17. Multi-Model Comparison of Southern Ocean and Sea Ice Trends in CORE-II and CMIP5 Model

    NASA Astrophysics Data System (ADS)

    Downes, S. M.; Griffies, S. M.; Farneti, R.; Marsland, S. J.; Uotila, P.; Hogg, A.

    2014-12-01

    The Southern Ocean circulation, influenced by buoyancy, momentum and sea ice processes, varies on seasonal to centennial timescales. Incomplete spatio-temporal observations of the full ocean water column, overlying ocean-ice-atmosphere fluxes, and adjacent polar dynamics challenge our ability to model the Southern Ocean. However, several studies have indicated this region is particularly important in the evolving climate, including the anthropogenic influences. Models coherently capture large-scale Southern Ocean patterns, however it is the magnitude and location of these patterns that varies widely. In particular, difficulties with modelling of small scale processes remains an outstanding issue. Here we review the representation of the Southern Ocean circulation, including fluxes at the ocean-ice and ocean-atmosphere interfaces, in numerous coupled climate models from two international modeling efforts, namely the Coordinated Ocean-ice Reference Experiments Phase II (CORE-II) and Coupled Model Intercomparison Project Phase 5 (CMIP5). We focus on the relationships between large scale and mesoscale overturning circulation, formation of key water masses and the associated deep winter mixed layers, buoyancy and wind fluxes, and sea ice. We identify major uncertainties in the modelling of past, present and projected large-scale ocean processes, and provide insights for future modelling directions.

  18. [Factor models of the Beck Depression Inventory-II. Validation with coronary patients and a critique of Ward's model].

    PubMed

    del Pino Pérez, Antonio; Ibáñez Fernández, Ignacio; Bosa Ojeda, Francisco; Dorta González, Ruth; Gaos Miezoso, María Teresa

    2012-02-01

    The objective of this study was to validate in a sample of 205 coronary patients a factor model for the BDI-II, especially a model that would allow for modeling of depressive symptoms after explicitly removing bias related to somatic symptoms of depression that would overlap those of heart disease. Exploratory and confirmatory factor analyses for ordinal data were conducted. A one-factor model, six correlated two-factor models and, derivatives thereof, seven models with a single General Depression factor and two uncorrelated factors, were analyzed. Exploratory analysis extracted two factors, Somatic-affective and Cognitive. Confirmatory factor analyses showed the worst fit for the one-factor model. Two-factor models were surpassed in goodness of fit by the models of general-factor and group factors. Among these, the General, Somatic-affective and Cognitive (G-Sa-C) model of Beck with students is noteworthy. The reduced General, Somatic and Cognitive (G-S-C) model of Ward showed the worst goodness of fit. Our model surpasses the cutoff criteria of all fit indexes. We conclude that the inclusion of a general-factor and group factors in all the models surpasses the results of G-S-C model and, therefore, questions it. The G-Sa-C model is strengthened.

  19. Vertical Chromium Distribution in the Atmospheres of CP Stars. II. Modeling

    NASA Astrophysics Data System (ADS)

    Savanov, I. S.; Kochukhov, O. P.; Tsymbal, V. V.

    2001-04-01

    Vertical chromium distributions in the atmospheres of several Ap and Am stars are fitted using detailed modeling of the profiles of CrII lines. The vertical distributions obtained for Ap stars are consistent with Babel's results of an investigation of Cr lines in the spectrum of the Ap star 53 Cam. It is shown that the observational data cannot be interpreted in terms of the hypothesis that microturbulent velocity varies with depth.

  20. Detailed p- and s-wave velocity models along the LARSE II transect, Southern California

    USGS Publications Warehouse

    Murphy, J.M.; Fuis, G.S.; Ryberg, T.; Lutter, W.J.; Catchings, R.D.; Goldman, M.R.

    2010-01-01

    Structural details of the crust determined from P-wave velocity models can be improved with S-wave velocity models, and S-wave velocities are needed for model-based predictions of strong ground motion in southern California. We picked P- and S-wave travel times for refracted phases from explosive-source shots of the Los Angeles Region Seismic Experiment, Phase II (LARSE II); we developed refraction velocity models from these picks using two different inversion algorithms. For each inversion technique, we calculated ratios of P- to S-wave velocities (VP/VS) where there is coincident P- and S-wave ray coverage.We compare the two VP inverse velocity models to each other and to results from forward modeling, and we compare the VS inverse models. The VS and VP/VS models differ in structural details from the VP models. In particular, dipping, tabular zones of low VS, or high VP/VS, appear to define two fault zones in the central Transverse Ranges that could be parts of a positive flower structure to the San Andreas fault. These two zones are marginally resolved, but their presence in two independent models lends them some credibility. A plot of VS versus VP differs from recently published plots that are based on direct laboratory or down-hole sonic measurements. The difference in plots is most prominent in the range of VP = 3 to 5 km=s (or VS ~ 1:25 to 2:9 km/s), where our refraction VS is lower by a few tenths of a kilometer per second from VS based on direct measurements. Our new VS - VP curve may be useful for modeling the lower limit of VS from a VP model in calculating strong motions from scenario earthquakes.

  1. Evaluation of a Sectoral Approach to Integrated Assessment Modelling (EuroDelta II)

    NASA Astrophysics Data System (ADS)

    Cuvelier, C.; Thunis, P.

    2009-04-01

    The EURODELTA II (ED II) project is the second phase of the EuroDelta co-operation project. The EuroDelta co-operation is intended to support the design of air pollution control strategies in Europe, both under the European Commission and under the Convention on Long-range Transboundary Air Pollution. The EuroDelta approach is to investigate the robustness of source-receptor relationships used in Integrated Assessment (IA) modelling by introducing an ensemble of models. The project is based on a collaboration between the European Commission Joint Research Centre (JRC) at Ispra (Italy) , five air quality modelling teams at Ineris (France), the Free University of Berlin (Germany), Met.no (Norway), TNO (Netherlands) and SMHI (Sweden) and the Oil Companies' European Organization for Environment, Health and Safety (CONCAWE). While the first phase of EuroDelta, ED I, examined the feasibility of using model ensembles to evaluate the robustness of source-receptor calculations in predicting recent (2000) and future (2020) air quality in Europe, the second phase ED II investigates the consequences of introducing sectoral approaches in integrated assessment modelling. A total of 60 different emission scenario calculations were evaluated to determine how the different models represent the impacts on a European scale of applying emission reductions to individual emission sectors. Emission reductions from power combustion, industry, residential and traffic sources were investigated independently and additional efforts were also addressed to investigate the effect of shipping emission control in the Mediterranean Sea. The main conclusion is that the impact of emission reductions in individual sectors is more appropriately described with the help of sectorally disaggregated source- receptor calculations. The recommendation is to incorporate sectoral weights to integrated assessment modelling in order to better support future revisions of European air pollution control policies

  2. Identification of antibody epitopes within the CB-11 peptide of type II collagen. II. Computer modelling studies of peptides and the interpretation of epitope scanning results.

    PubMed

    Brass, A; Worthington, J; Chen, Y; Morgan, K

    1991-01-01

    Computer modelling techniques were used to investigate the structure of 8-mers from the CB-11 peptide of bovine type II collagen which were recognised by sera from rats which had previously been injected with bovine type II collage. It was discovered that all the hydrophobic peptides recognised by the rat sera were predicted to have collagenous-like secondary structures. The primary structure of the 8-mers which were recognised was also compared against the sequences in the OWL protein sequence database. The combined results of the computer modelling and sequence analysis suggested that the sequence Gly-Pro-Gly-Phe-Pro is a minimal B cell epitope of the CB-11 fragment of bovine type II collagen.

  3. RNA Pol II transcription model and interpretation of GRO-seq data.

    PubMed

    Lladser, Manuel E; Azofeifa, Joseph G; Allen, Mary A; Dowell, Robin D

    2017-01-01

    A mixture model and statistical method is proposed to interpret the distribution of reads from a nascent transcriptional assay, such as global run-on sequencing (GRO-seq) data. The model is annotation agnostic and leverages on current understanding of the behavior of RNA polymerase II. Briefly, it assumes that polymerase loads at key positions (transcription start sites) within the genome. Once loaded, polymerase either remains in the initiation form (with some probability) or transitions into an elongating form (with the remaining probability). The model can be fit genome-wide, allowing patterns of Pol II behavior to be assessed on each distinct transcript. Furthermore, it allows for the first time a principled approach to distinguishing the initiation signal from the elongation signal; in particular, it implies a data driven method for calculating the pausing index, a commonly used metric that informs on the behavior of RNA polymerase II. We demonstrate that this approach improves on existing analyses of GRO-seq data and uncovers a novel biological understanding of the impact of knocking down the Male Specific Lethal (MSL) complex in Drosophilia melanogaster.

  4. Kinetic and isotope analyses of tetrachloroethylene and trichloroethylene degradation by model Fe(II)-bearing minerals.

    PubMed

    Liang, Xiaoming; Philp, R Paul; Butler, Elizabeth C

    2009-03-01

    The kinetics and in some cases stable carbon isotope fractionation associated with abiotic reductive dechlorination of tetrachloroethylene (PCE) and trichloroethylene (TCE) by model Fe(II)-bearing minerals present in anaerobic soils were measured. The minerals studied were chloride green rust (GR-Cl), sulfate green rust (GR-SO(4)), pyrite, magnetite, and adsorbed Fe(II) or FeS formed at the surface of goethite by treatment with dissolved Fe(II) or S(-II). We observed some abiotic transformation of PCE and TCE in every system studied, as evidenced by the presence of abiotic reaction products. Bulk enrichment factors (epsilon(bulk) values) for TCE transformation by GR-Cl and pyrite were -23.0+/-1.8 per thousand and -21.7+/-1.0 per thousand, respectively, which are more negative than reported values for microbial TCE dechlorination and could provide one means for distinguishing microbial from abiotic dechlorination of TCE in the environment. Considering the time scale of subsurface remediation technologies, including natural attenuation, minerals such as green rusts, pyrite, and magnetite have the potential to contribute to the transformation of PCE and TCE at contaminated sites.

  5. Modeling of copper(II) and lead(II) adsorption on kaolinite-based clay minerals individually and in the presence of humic acid.

    PubMed

    Hizal, Jülide; Apak, Resat

    2006-03-01

    The aim of this study is to explain how clay minerals adsorb heavy metals individually and in the presence of humic acid, and to model heavy metal adsorption specifically based on surface-metal binary and surface-metal-ligand ternary complexation. The adsorption of Cu(II) and Pb(II) on kaolinite-based clay minerals has been modeled by the aid of the FITEQL3.2 computer program using single- and double-site binding models of the Langmuir approach. Potentiometric titrations and adsorption capacity experiments were carried out in solutions containing different concentrations of the inert electrolyte NaClO4; however, the modeling of binary and ternary surface complexation was deliberately done at high ionic strength (0.1 M electrolyte) for eliminating adsorption onto the permanent negatively charged sites of kaolinite. A "two-site, two pKa" model was adapted, and as for the two surface sites responsible for adsorption, it may be arbitrarily assigned that [triple bond]S1OH sites represent silanol and organic functional groups such as carboxyl having pKa values close to that of silanol, and [triple bond]S2OH sites represent aluminol and organic functional groups such as phenolics whose pKa values are close to that of aluminol, as all the studied clays contained organic carbon. Copper(II) showed a higher adsorption capacity and higher binding constants, while lead(II), being a softer cation (in respect to HSAB theory) preferred the softer basic sites with aluminol-phenol functional groups. Heavy metal cations are assumed to bind to the clay surface as the sole (unhydrolyzed) M(II) ion and form monodentate surface complexes. Cu(II) and Pb(II) adsorption in the presence of humic acid was modeled using a double-site binding model by the aid of FITEQL3.2, and then the whole system including binary surface-metal and surface-ligand and ternary surface-metal-ligand complexes was resolved with respect to species distributions and relevant stability constants. Electrostatic effects

  6. Modeling of G333.6-0.2 as a spherical H II region

    NASA Technical Reports Server (NTRS)

    Rubin, R. H.; Hollenbach, D. J.; Erickson, E. F.

    1983-01-01

    The radio and IR observations of the H II region G333.6-0.2 are matched with a detailed spherical model with a density distribution which has a uniform-density core of radius 0.05 pc, a power-law intermediate zone, and a uniform-density halo. A stellar radiation field is required that is somewhat different from those predicted by available model atmospheres. Of the stellar models of Kurucz, the Teff = 34,000 K and log g = 3.5 model best fits the observed ratio of helium to hydrogen recombination lines. A good fit to all the observations in obtained with an S(2+) ionizing flux which is a factor of 20 times less than predicted by the Kurucz atmosphere. Current model atmospheres may not be appropriate because a single stable star with Teff = 34,000 K fails by at least an order of magnitude to produce the ionizing luminosity. The small radius of the constant-density core implies a short dynamical lifetime of approximately 5000 years for this spherical model; this may indicate that a nonspherical blister geometry is more appropriate for this H II region.

  7. MICS-Asia II: Model intercomparison and evaluation of particulate sulfate, nitrate and ammonium

    NASA Astrophysics Data System (ADS)

    Hayami, Hiroshi; Sakurai, T.; Han, Z.; Ueda, H.; Carmichael, G. R.; Streets, D.; Holloway, T.; Wang, Z.; Thongboonchoo, N.; Engardt, M.; Bennet, C.; Fung, C.; Chang, A.; Park, S. U.; Kajino, M.; Sartelet, K.; Matsuda, K.; Amann, M.

    Eight chemical transport models participate in a model intercomparison study for East Asia, MICS-Asia II. This paper analyzes calculated results for particulate matter of sulfate, nitrate and ammonium through comparisons with each other and with monthly measurements at EANET (the acid deposition monitoring network in East Asia) and daily measurements at Fukue, Japan. To the EANET measurements, model ensemble means better agree with model individual results for sulfate and total ammonium, although total nitrate is consistently and considerably underestimated. To measurements at Fukue, the models show better agreement than for the EANET measurements. This is likely because Fukue is centered in many of the model domains, whereas the EANET stations are mostly in Southeast Asia and Russia. Moreover, it would be important that Fukue is in Northeast Asia, where the emission inventory is more reliable than Southeast Asia. The model-model comparisons are made in view of the total amount in the atmosphere, vertical profile, coefficient of variation in surface concentrations, and transformation changes with distance. All the models show reasonable tendencies in vertical profiles and composition ratios. However, total amounts in the atmosphere are discrepant among the models. The consistency of the total amount in the atmosphere would influence source-receptor analysis. It seems that model results would be consistent, if the models take into account the primitive processes like emission, advection/diffusion, chemical transformation and dry/wet deposition, no matter the processes are modeled simply or comprehensively. Through the comparison study, we learned that it would be difficult to find any problems from one comparison (model-observation comparison with one data or many but at one station or in a short period). Modelers tend to examine model performances only from model-observation comparisons. However, taking budget in a certain or whole model domain would be important

  8. Transient PVT measurements and model predictions for vessel heat transfer. Part II.

    SciTech Connect

    Felver, Todd G.; Paradiso, Nicholas Joseph; Winters, William S., Jr.; Evans, Gregory Herbert; Rice, Steven F.

    2010-07-01

    Part I of this report focused on the acquisition and presentation of transient PVT data sets that can be used to validate gas transfer models. Here in Part II we focus primarily on describing models and validating these models using the data sets. Our models are intended to describe the high speed transport of compressible gases in arbitrary arrangements of vessels, tubing, valving and flow branches. Our models fall into three categories: (1) network flow models in which flow paths are modeled as one-dimensional flow and vessels are modeled as single control volumes, (2) CFD (Computational Fluid Dynamics) models in which flow in and between vessels is modeled in three dimensions and (3) coupled network/CFD models in which vessels are modeled using CFD and flows between vessels are modeled using a network flow code. In our work we utilized NETFLOW as our network flow code and FUEGO for our CFD code. Since network flow models lack three-dimensional resolution, correlations for heat transfer and tube frictional pressure drop are required to resolve important physics not being captured by the model. Here we describe how vessel heat transfer correlations were improved using the data and present direct model-data comparisons for all tests documented in Part I. Our results show that our network flow models have been substantially improved. The CFD modeling presented here describes the complex nature of vessel heat transfer and for the first time demonstrates that flow and heat transfer in vessels can be modeled directly without the need for correlations.

  9. Comparative modeling of the three-dimensional structure of type II antifreeze protein.

    PubMed Central

    Sönnichsen, F. D.; Sykes, B. D.; Davies, P. L.

    1995-01-01

    Type II antifreeze proteins (AFP), which inhibit the growth of seed ice crystals in the blood of certain fishes (sea raven, herring, and smelt), are the largest known fish AFPs and the only class for which detailed structural information is not yet available. However, a sequence homology has been recognized between these proteins and the carbohydrate recognition domain of C-type lectins. The structure of this domain from rat mannose-binding protein (MBP-A) has been solved by X-ray crystallography (Weis WI, Drickamer K, Hendrickson WA, 1992, Nature 360:127-134) and provided the coordinates for constructing the three-dimensional model of the 129-amino acid Type II AFP from sea raven, to which it shows 19% sequence identity. Multiple sequence alignments between Type II AFPs, pancreatic stone protein, MBP-A, and as many as 50 carbohydrate-recognition domain sequences from various lectins were performed to determine reliably aligned sequence regions. Successive molecular dynamics and energy minimization calculations were used to relax bond lengths and angles and to identify flexible regions. The derived structure contains two alpha-helices, two beta-sheets, and a high proportion of amino acids in loops and turns. The model is in good agreement with preliminary NMR spectroscopic analyses. It explains the observed differences in calcium binding between sea raven Type II AFP and MBP-A. Furthermore, the model proposes the formation of five disulfide bridges between Cys 7 and Cys 18, Cys 35 and Cys 125, Cys 69 and Cys 100, Cys 89 and Cys 111, and Cys 101 and Cys 117.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7540906

  10. Synthesis, characterization, biological activity, molecular modeling and docking studies of complexes 4-(4-hydroxy)-3-(2-pyrazine-2-carbonyl)hydrazonomethylphenyl-diazen-yl-benzenesulfonamide with manganese(II), cobalt(II), nickel(II), zinc(II) and cadmium(II)

    NASA Astrophysics Data System (ADS)

    Alaghaz, Abdel-Nasser M. A.; Zayed, Mohamed E.; Alharbi, Suliman A.; Ammar, Reda A. A.; Elhenawy, Ahmed

    2015-03-01

    A new series of complexes of 4-(4-hydroxy)-3-(2-pyrazine-2-carbonyl)hydrazonomethylphenyl-diazen-yl-benzenesulfonamide (HL) with Mn(II), Co(II), Ni(II), Zn(II) and Cd(II) have been prepared and characterized by different physical techniques. The IR spectra of the prepared complexes were suggested that the ligand behaves as a tri-dentate ligand through the carbonyl oxygen, azomethine nitrogen and phenolic oxygen atoms (ONO). Electronic spectra and magnetic susceptibility measurements reveal octahedral geometry for all complexes. The elemental analyses and mass spectral data have justified the ML2 composition of complexes. The EPR spectra of Mn(II), Co(II) and Ni(II) complexes support the mononuclear structure. The crystal field splitting, Racah repulsion and nephelauxetic parameters and determined from the electronic spectra of the complexes. Thermal properties and decomposition kinetics of all complexes are investigated. The geometry of the metal complexes has been optimized with the help of molecular modeling. The biological activity of these compounds against various fungi has been investigated.

  11. Dynamical Models of Mira Atmospheres: Shocks, Limb Functions, and MG II Emission

    NASA Astrophysics Data System (ADS)

    Beach, Thomas Eugene

    1990-01-01

    Dynamic atmosphere models of Mira-type stars, prepared using a code developed by G. H. Bowen, were analyzed to determine observational implications of the models and suggest improvements to the code and model parameters. Three specific areas were addressed: Shock morphology, limb functions, and Mg II emission. The long-period, fundamental-mode models used in this study exhibit an unexpected shock morphology. In addition to the "main" shock, which forms as the radially pulsating surface of the Mira moves outward and is observed to travel out through atmosphere, a "preliminary" shock structure forms as rebounding layers of the atmosphere fall back onto lower layers. The preliminary shock remains deep in the atmosphere until overrun by the outward-moving main shock. The energy dissipated by the preliminary shock usually exceeds that dissipated by the main shock, and has important effects on the light curve. The dynamic atmosphere models exhibit radial extension of the atmosphere and post-shock emission that alter the limb function (limb darkening/brightening) of the models. The effects on stellar angular diameters measured by lunar occultation technique are calculated. The results show that the usual procedure of fitting occultation observations assuming a uniform brightness disk and then correcting the resulting diameter for limb darkening can give erroneous results. The dynamic effects cause Miras to appear larger and cooler than they actually are. A post-shock relaxation zone code developed by J. N. Pierce was modified and interfaced with the Bowen code to follow the ionization state and cooling radiation emitted by Hydrogen, Helium, and 23 metals in the models. Mg II emission data were used to prepare a light curve that is compared with Mg II light curves observed with the IUE satellite. The relaxation models show that the periodic passage of shocks through the atmosphere results in much lower concentrations of molecular hydrogen and higher ionization fractions

  12. Generalized model for the diffusion of solvents in glassy polymers: From Fickian to Super Case II

    NASA Astrophysics Data System (ADS)

    Miao, Jiayuan; Tsige, Mesfin; Taylor, Philip L.

    2017-07-01

    The diffusion of small solvent molecules in glassy polymers may take on a variety of different forms. Fickian, anomalous, Case II and Super Case II diffusion have all been observed, and theoretical models exist that describe each specific type of behavior. Here we present a single generalized kinetic model capable of yielding all these different types of diffusion on the basis of just two parameters. The principal determinant of the type of diffusion is observed to be a dimensionless parameter, γ , that describes the influence of solvent-induced swelling in lowering the potential barriers separating available solvent sites. A second parameter, η , which characterizes the effect of the solvent in reducing the potential energy of a solvent molecule when at rest at an available site, only influences the type of diffusion to a lesser extent. The theoretical analysis does not include any effects that are explicitly non-local in time, an example of which is the inclusion of polymer viscosity in the Thomas-Windle model; it thus represents a variant of Fick's second law utilizing a concentration-dependent diffusivity when η is small. To check the significance of time-delayed swelling, a simulation of a modified model was performed that contained a history-dependent term. The results were found to be very similar to those in the time-local model.

  13. Saturation magnetization of Ni(II) in metalloproteins and model compounds

    SciTech Connect

    Sendova, M.; Day, E.P.; Kiick, K.; Johnson, M.; Ma, L.; Scott, B.; Hausinger, R.; Todd, M.; Peterson, J. Univ. of Georgia, Athens Michigan State Univ., East Lansing Univ. of Alabama, Tuscaloosa )

    1992-01-01

    The Ni(II) sites of urease (from Klebsiella aerogenes and jack bean), coenzyme F[sub 430] (from Methanobacterium thermoautotrophicum), and several model compounds having octahedral symmetry have been studied using the saturation megnetization technique. Data were collected at four fixed fields over the temperature range from 2 - 200K. Theoretical curves calculated from the spin Hamiltonian were used to fit the experimentally obtained magnetization curves. The following parameters were determined: the spine state (S), the amount of the sample in this spin state ([S]), the gyromagnetic ratio (g), and the zero field splitting parameters (D, E/D). The amount of S=1 paramagnetism of the Ni(II) sites was found to depend on the pH of the buffer and on the concentration of the protein in D[sub 2]O (for coenzyme F[sub 430]). The relationship of the strength of the ligand field to the zero field splitting parameter was studied for the model compounds. There was no evidence for exchange coupling between the two Ni(II) ions at the active sites of either plant or bacterial urease.

  14. Developing multisite empirical force field models for Pt(II) and cisplatin.

    PubMed

    Cvitkovic, John P; Kaminski, George A

    2017-01-30

    We have developed empirical force field parameters for Pt(II) and cisplatin. Two force field frameworks were used-modified OPLS-AA and our second-order polarizable POSSIM. A seven-site model was used for the Pt(II) ion. The goal was to create transferable parameter sets compatible with the force field models for proteins and general organic compounds. A number of properties of the Pt(II) ion and its coordination compounds have been considered, including geometries and energies of the complexes, hydration free energy, and radial distribution functions in water. Comparison has been made with experimental and quantum mechanical results. We have demonstrated that both versions are generally capable of reproducing key properties of the system, but the second-order polarizable POSSIM formalism permits more accurate quantitative results to be obtained. For example, the energy of formation of cisplatin as calculated with the modified OPLS-AA exhibited an error of 9.9%, while the POSSIM error for the same quantity was 6.2%. The produced parameter sets are transferable and suitable to be used in protein-metal binding simulations in which position or even coordination of the ion does not have to be constrained using preexisting knowledge. © 2016 Wiley Periodicals, Inc.

  15. Large-scale Validation of AMIP II Land-surface Simulations: Preliminary Results for Ten Models

    SciTech Connect

    Phillips, T J; Henderson-Sellers, A; Irannejad, P; McGuffie, K; Zhang, H

    2005-12-01

    This report summarizes initial findings of a large-scale validation of the land-surface simulations of ten atmospheric general circulation models that are entries in phase II of the Atmospheric Model Intercomparison Project (AMIP II). This validation is conducted by AMIP Diagnostic Subproject 12 on Land-surface Processes and Parameterizations, which is focusing on putative relationships between the continental climate simulations and the associated models' land-surface schemes. The selected models typify the diversity of representations of land-surface climate that are currently implemented by the global modeling community. The current dearth of global-scale terrestrial observations makes exacting validation of AMIP II continental simulations impractical. Thus, selected land-surface processes of the models are compared with several alternative validation data sets, which include merged in-situ/satellite products, climate reanalyses, and off-line simulations of land-surface schemes that are driven by observed forcings. The aggregated spatio-temporal differences between each simulated process and a chosen reference data set then are quantified by means of root-mean-square error statistics; the differences among alternative validation data sets are similarly quantified as an estimate of the current observational uncertainty in the selected land-surface process. Examples of these metrics are displayed for land-surface air temperature, precipitation, and the latent and sensible heat fluxes. It is found that the simulations of surface air temperature, when aggregated over all land and seasons, agree most closely with the chosen reference data, while the simulations of precipitation agree least. In the latter case, there also is considerable inter-model scatter in the error statistics, with the reanalyses estimates of precipitation resembling the AMIP II simulations more than to the chosen reference data. In aggregate, the simulations of land-surface latent and sensible

  16. Progresses in tritium accident modelling in the frame of IAEA EMRAS II

    SciTech Connect

    Galeriu, D.; Melintescu, A.

    2015-03-15

    The assessment of the environmental impact of tritium release from nuclear facilities is a topic of interest in many countries. In the IAEA's Environmental Modelling for Radiation Safety (EMRAS I) programme, progresses for routine releases were done and in the EMRAS II programme a dedicated working group (WG 7 - Tritium Accidents) focused on the potential accidental releases (liquid and atmospheric pathways). The progresses achieved in WG 7 were included in a complex report - a technical document of IAEA covering both liquid and atmospheric accidental release consequences. A brief description of the progresses achieved in the frame of EMRAS II WG 7 is presented. Important results have been obtained concerning washout rate, the deposition on the soil of HTO and HT, the HTO uptake by leaves and the subsequent conversion to OBT (organically bound tritium) during daylight. Further needs of the processes understanding and the experimental efforts are emphasised.

  17. BESS-Polar II Hydrogen and Helium Isotope Measurements to Constrain Cosmic-Ray Propagation Models

    NASA Astrophysics Data System (ADS)

    Picot-Clemente, Nicolas; BESS-Polar Collaboration

    2017-01-01

    The Balloon-borne Experiment with Superconducting Spectrometer BESS-Polar II flew over Antarctica for 24.5 days from December 2007 through January 2008, during the 23rd solar cycle minimum. The instrument is made of complementary particle detectors which allow to precisely measure the charge, velocity and rigidity of incoming cosmic rays. It can accurately separate cosmic-ray hydrogen and helium isotopes from 0.2 to 1.5 GeV/nucleon. Flux and secondary-to-primary ratios of these particles can bring important information to better understand the cosmic-ray propagation history in the Galaxy. BESS-Polar II provides the most precise isotope measurements to date between 0.2 and 1.5 GeV/nucleon. These data will be reported and constraints on cosmic-ray propagation models, using the GALPROP program, will be discussed.

  18. Designing Type-II staggered model ternary copolymers using ant algorithm

    NASA Astrophysics Data System (ADS)

    Garg, Aparna; Bakhshi, A. K.

    2010-12-01

    Ant algorithm has been applied in combination with the simple negative factor counting (NFC) method and the inverse iteration method (IIM) to the designing of Type-II staggered model ternary copolymers. Two types of copolymers have been studied, one in which the band widths of the homopolymers were identical and their band-gaps were different and vice versa. On the basis of the optimized results obtained in both the cases it has been found that (i) the band-gap of the copolymer is closest to that of the lowest band-gap component and (ii) the component having the lowest ionization potential has the maximum amount in the optimum solution. Further, the optimized results are found to be nearly independent of the seed used. The density of states has also been investigated for all the copolymers. The results obtained are expected to be important guidelines for molecular designing of copolymers with tailor-made conduction properties.

  19. Proposal for a "phase II" multicenter trial model for preclinical new antiepilepsy therapy development.

    PubMed

    O'Brien, Terence J; Ben-Menachem, Elinor; Bertram, Edward H; Collins, Stephen D; Kokaia, Merab; Lerche, Holger; Klitgaard, Henrik; Staley, Kevin J; Vaudano, Elisabetta; Walker, Matthew C; Simonato, Michele

    2013-08-01

    There is a pressing need to address the current major gaps in epilepsy treatment, in particular drug-resistant epilepsy, antiepileptogenic therapies, and comorbidities. A major concern in the development of new therapies is that current preclinical testing is not sufficiently predictive for clinical efficacy. Methodologic limitations of current preclinical paradigms may partly account for this discrepancy. Here we propose and discuss a strategy for implementing a "phase II" multicenter preclinical drug trial model based on clinical phase II/III studies designed to generate more rigorous preclinical data for efficacy. The goal is to improve the evidence resulting from preclinical studies for investigational new drugs that have shown strong promise in initial preclinical "phase I" studies. This should reduce the risk for expensive clinical studies in epilepsy and therefore increase the appeal for funders (industry and government) to invest in their clinical development.

  20. Synthesis, spectroscopic characterization, molecular modeling and antimicrobial activities of Mn(II), Co(II), Ni(II), Cu(II) complexes containing the tetradentate aza Schiff base ligand

    NASA Astrophysics Data System (ADS)

    Chandra, Sulekh; Ruchi

    2013-02-01

    Mn(II), Co(II), Ni(II), and Cu(II) complexes with a tetradentate macrocyclic ligand [1.2.5.6tetraoxo-3,4,7,8tetraaza-(1,2,3,4,5,6,7,8)tetrabenzene(L)] were synthesized and characterized by elemental analysis, molar conductance measurements, mass, nmr, i.r., electronic and e.p.r. spectral studies. All the complexes are non electrolytes in nature and may be formulated as [M(L)X2] [where, M = Mn(II), Co(II), Ni(II), Cu(II) and X = Cl-, CH3COO-]. On the basis of i.r., electronic and e.p.r. spectral studies a distorted octahedral geometry has been assigned for all complexes. The antimicrobial activities and LD50 values of the ligand and its complexes, as growth inhibiting agents, have been screened in vitro against two different species of bacteria and plant pathogenic fungi.

  1. Reduction of GAG storage in MPS II mouse model following implantation of encapsulated recombinant myoblasts.

    PubMed

    Friso, Adelaide; Tomanin, Rosella; Alba, Sabrina; Gasparotto, Nicoletta; Puicher, Elisabetta Piller; Fusco, Mariella; Hortelano, Gonzalo; Muenzer, Joseph; Marin, Oriano; Zacchello, Franco; Scarpa, Maurizio

    2005-11-01

    Hunter syndrome, mucopolysaccharidosis type II (MPS II), is a X-linked inherited disorder caused by the deficiency of the enzyme iduronate-2-sulfatase (IDS), involved in the lysosomal catabolism of the glycosaminoglycans (GAG) dermatan and heparan sulfate. Such a deficiency leads to the intracellular accumulation of undegraded GAG and eventually to a progressive severe clinical pattern. Many attempts have been made in the last two to three decades to identify possible therapeutic strategies for the disorder, including gene therapy and somatic cell therapy. In this study we evaluated the intraperitoneal implantation of allogeneic myoblasts over-expressing IDS, enclosed in alginate microcapsules, in the MPS II mouse model. Animals were monitored for 8 weeks post-implantation, during which plasma and tissue IDS levels, as well as tissue and urinary GAG contents, were measured. Induced enzyme activity occurred both in the plasma and in the different tissues analyzed. A significant decrease in urinary undegraded GAG between the fourth and the sixth week of treatment was observed. Moreover, a biochemical reduction of GAG deposits was measured 8 weeks after treatment in the liver and kidney, on average 30 and 38%, respectively, while in the spleen GAG levels were almost normalized. Finally, the therapeutic effect was confirmed by histolochemical examination of the same tissues. Such effects were obtained following implantation of about 1.5 x 10(6) recombinant cells/animal. Taken together, these results represent a clear evidence of the therapeutic efficacy of this strategy in the MPS II mouse model, and encourage further evaluation of this approach for potential treatment of human beings. Copyright (c) 2005 John Wiley & Sons, Ltd.

  2. Modelling the Pan-Spectral Energy Distribution of Starburst Galaxies: II. Control of the H II Region Parameters

    SciTech Connect

    Dopita, M A; Fischera, J; Sutherland, R S; Kewley, L J; Tuffs, R J; Popescu, C C; van Breugel, W; Groves, B A; Leitherer, C

    2006-03-01

    We examine from a theoretical viewpoint how the physical parameters of H II regions are controlled both in normal galaxies and in starburst environments. These parameters are the H II region luminosity function, the time-dependent size, the covering fraction of molecular clouds, the pressure in the ionized gas and the ionization parameter. The factors which control them are the initial mass function of the exciting stars, the cluster mass function, the metallicity and the mean pressure in the surrounding interstellar medium. We investigate the sensitivity of the H{alpha} luminosity to the IMF, and find that this can translate to about 30% variation in derived star formation rates. The molecular cloud dissipation timescale is estimated from a case study of M17 to be {approx} 1 Myr. Based upon H II luminosity function fitting for nearby galaxies, we propose that the cluster mass function has a log-normal form peaking at {approx} 185M{sub {circle_dot}}. This suggests that the cluster mass function is the continuation of the stellar IMF to higher mass. The pressure in the H II regions is controlled by the mechanical luminosity flux from the central cluster. Since this is closely related to the ionizing photon flux, we show that the ionization parameter is not a free variable, and that the diffuse ionized medium may be composed of many large, faint and old H II regions. Finally, we derive theoretical probability distributions for the ionization parameter as a function of metallicity and compare these to those derived for SDSS galaxies.

  3. Zn(II)-curcumin protects against hemorheological alterations, oxidative stress and liver injury in a rat model of acute alcoholism.

    PubMed

    Yu, Chuan; Mei, Xue-Ting; Zheng, Yan-Ping; Xu, Dong-Hui

    2014-03-01

    Curcumin can chelate metal ions, forming metallocomplexes. We compared the effects of Zn(II)-curcumin with curcumin against hemorheological alterations, oxidative stress and liver injury in a rat model of acute alcoholism. Oral administration of Zn(II)-curcumin dose-dependently prevented the ethanol-induced elevation of serum malondialdehyde (MDA) content and reductions in glutathione level and superoxide dismutase (SOD) activity. Zn(II)-curcumin also inhibited ethanol-induced liver injury. Additionally, Zn(II)-curcumin dose-dependently inhibited hemorheological abnormalities, including the ethanol-induced elevation of whole blood viscosity, plasma viscosity, blood viscosity at corrected hematocrit (45%), erythrocyte aggregation index, erythrocyte rigidity index and hematocrit. Compared to curcumin at the same dose, Zn(II)-curcumin more effectively elevated SOD activity, ameliorated liver injury and improved hemorheological variables. These results suggest that Zn(II)-curcumin protected the rats from ethanol-induced liver injury and hemorheological abnormalities via the synergistic effect of curcumin and zinc.

  4. Models of H II regions - Heavy element opacity, variation of temperature

    NASA Technical Reports Server (NTRS)

    Rubin, R. H.

    1985-01-01

    A detailed set of H II region models that use the same physics and self-consistent input have been computed and are used to examine where in parameter space the effects of heavy element opacity is important. The models are briefly described, and tabular data for the input parameters and resulting properties of the models are presented. It is found that the opacities of C, Ne, O, and to a lesser extent N play a vital role over a large region of parameter space, while S and Ar opacities are negligible. The variation of the average electron temperature T(e) of the models with metal abundance, density, and T(eff) is investigated. It is concluded that by far the most important determinator of T(e) is metal abundance; an almost 7000 K difference is expected over the factor of 10 change from up to down abundances.

  5. Chemical modeling of iron(II)/(III) solutions in hydrometallurgy using OLI(TM)

    NASA Astrophysics Data System (ADS)

    Carlos, Michael Kardono

    Iron is the most common impurity in hydrometallurgy which is usually removed by precipitation of insoluble iron compounds, such as hematite and jarosite. The knowledge of iron solubility in multicomponent solutions is important for design and optimization of the iron removal steps. The OLI Software package is a chemical modeling tool that incorporates the powerful mixed-solvent electrolyte (MSE) model capable of performing simulations of multicomponent electrolyte solutions from the freezing point up to the limit of fused salt and near the critical temperature of the solution. Literature or experimental solubility data was fitted on the OLI MSE model to improve the performance in simulating multicomponent Fe(II)/Fe(III) solutions. The particular focus of this work aimed at developing simulation capability for the FeCl 3-MgCl2-HCl-H2O system through experimental solubility measurement and modeling, relevant to atmospheric processing of saprolites by HCl using MgCl2 brines.

  6. Models of H II regions - Heavy element opacity, variation of temperature

    NASA Technical Reports Server (NTRS)

    Rubin, R. H.

    1985-01-01

    A detailed set of H II region models that use the same physics and self-consistent input have been computed and are used to examine where in parameter space the effects of heavy element opacity is important. The models are briefly described, and tabular data for the input parameters and resulting properties of the models are presented. It is found that the opacities of C, Ne, O, and to a lesser extent N play a vital role over a large region of parameter space, while S and Ar opacities are negligible. The variation of the average electron temperature T(e) of the models with metal abundance, density, and T(eff) is investigated. It is concluded that by far the most important determinator of T(e) is metal abundance; an almost 7000 K difference is expected over the factor of 10 change from up to down abundances.

  7. A GLOBAL MODEL OF THE LIGHT CURVES AND EXPANSION VELOCITIES OF TYPE II-PLATEAU SUPERNOVAE

    SciTech Connect

    Pejcha, Ondřej; Prieto, Jose L.

    2015-02-01

    We present a new self-consistent and versatile method that derives photospheric radius and temperature variations of Type II-Plateau supernovae based on their expansion velocities and photometric measurements. We apply the method to a sample of 26 well-observed, nearby supernovae with published light curves and velocities. We simultaneously fit ∼230 velocity and ∼6800 mag measurements distributed over 21 photometric passbands spanning wavelengths from 0.19 to 2.2 μm. The light-curve differences among the Type II-Plateau supernovae are well modeled by assuming different rates of photospheric radius expansion, which we explain as different density profiles of the ejecta, and we argue that steeper density profiles result in flatter plateaus, if everything else remains unchanged. The steep luminosity decline of Type II-Linear supernovae is due to fast evolution of the photospheric temperature, which we verify with a successful fit of SN 1980K. Eliminating the need for theoretical supernova atmosphere models, we obtain self-consistent relative distances, reddenings, and nickel masses fully accounting for all internal model uncertainties and covariances. We use our global fit to estimate the time evolution of any missing band tailored specifically for each supernova, and we construct spectral energy distributions and bolometric light curves. We produce bolometric corrections for all filter combinations in our sample. We compare our model to the theoretical dilution factors and find good agreement for the B and V filters. Our results differ from the theory when the I, J, H, or K bands are included. We investigate the reddening law toward our supernovae and find reasonable agreement with standard R{sub V}∼3.1 reddening law in UBVRI bands. Results for other bands are inconclusive. We make our fitting code publicly available.

  8. Visual imagery and the user model applied to fuel handling at EBR-II

    SciTech Connect

    Brown-VanHoozer, S.A.

    1995-06-01

    The material presented in this paper is based on two studies involving visual display designs and the user`s perspective model of a system. The studies involved a methodology known as Neuro-Linguistic Programming (NLP), and its use in expanding design choices which included the ``comfort parameters`` and ``perspective reality`` of the user`s model of the world. In developing visual displays for the EBR-II fuel handling system, the focus would be to incorporate the comfort parameters that overlap from each of the representation systems: visual, auditory and kinesthetic then incorporate the comfort parameters of the most prominent group of the population, and last, blend in the other two representational system comfort parameters. The focus of this informal study was to use the techniques of meta-modeling and synesthesia to develop a virtual environment that closely resembled the operator`s perspective of the fuel handling system of Argonne`s Experimental Breeder Reactor - II. An informal study was conducted using NLP as the behavioral model in a v reality (VR) setting.

  9. Oral administration of undenatured native chicken type II collagen (UC-II) diminished deterioration of articular cartilage in a rat model of osteoarthritis (OA).

    PubMed

    Bagi, C M; Berryman, E R; Teo, S; Lane, N E

    2017-09-06

    The aim of this study was to determine the ability of undenatured native chicken type II collagen (UC-II) to prevent excessive articular cartilage deterioration in a rat model of osteoarthritis (OA). Twenty male rats were subjected to partial medial meniscectomy tear (PMMT) surgery to induce OA. Immediately after the surgery 10 rats received vehicle and another 10 rats oral daily dose of UC-II at 0.66 mg/kg for a period of 8 weeks. In addition 10 naïve rats were used as an intact control and another 10 rats received sham surgery. Study endpoints included a weight-bearing capacity of front and hind legs, serum biomarkers of bone and cartilage metabolism, analyses of subchondral and cancellous bone at the tibial epiphysis and metaphysis, and cartilage pathology at the medial tibial plateau using histological methods. PMMT surgery produced moderate OA at the medial tibial plateau. Specifically, the deterioration of articular cartilage negatively impacted the weight bearing capacity of the operated limb. Immediate treatment with the UC-II preserved the weight-bearing capacity of the injured leg, preserved integrity of the cancellous bone at tibial metaphysis and limited the excessive osteophyte formation and deterioration of articular cartilage. Study results demonstrate that a clinically relevant daily dose of UC-II when applied immediately after injury can improve the mechanical function of the injured knee and prevent excessive deterioration of articular cartilage. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  10. Arms race modeling: systematic analysis and synthesis. (Volumes I and II)

    SciTech Connect

    Anderton, C.H.

    1986-01-01

    In recent years there has been a significant proliferation of arms race models in journals and books across many disciplines. Numerous factors have been put forth as relevant by arms race modelers and diverse analytical and explanatory approaches have been employed. This indicates that arms race modeling can be advanced by a systematic analysis (review) and synthesis. This is the purpose of this thesis). Part I discusses the perspective, purposes, and organization of this thesis, definitions of arms race, and mathematical modeling as a tool of arms race research. Parts II-VI review in detail over 125 arms race models and numerous other defense determination models. Part VII synthesizes arms race modeling factors and approaches from the perspective of economics. Each side in an arms race is viewed as facing an economic choice problem of how to allocate scarce resources between defense and nondefense goods. Part VIII undertakes policy analysis using the models developed in Part VII. The three issues investigated are (1) nuclear-conventional substitutability in the European theater, (2) the Strategic Defense Initiative, and (3) the impact of arms races on outputs and factor rewards. Part IX discusses future research avenues related to arms race modeling.

  11. MICS-Asia II: Model inter-comparison and evaluation of acid deposition

    NASA Astrophysics Data System (ADS)

    Wang, Zifa; Xie, Fuying; Sakurai, T.; Ueda, H.; Han, Zhiwei; Carmichael, G. R.; Streets, D.; Engardt, M.; Holloway, T.; Hayami, H.; Kajino, M.; Thongboonchoo, N.; Bennet, C.; Park, S. U.; Fung, C.; Chang, A.; Sartelet, K.; Amann, M.

    This paper focuses on the comparison of chemical deposition of eight regional chemical models used in Model Inter-Comparison Study for Asia (MICS-Asia) II. Monthly-mean depositions of chemical species simulated by these models, including dry deposition of SO 2, HNO 3, NH 3, sulfate, nitrate and ammonium and wet deposition of SO 42-, NO 3- and NH 4+, have been provided for four periods (March, July, December 2001 and March 2002) in this work. Observations at 37 sites of the Acid Deposition Monitoring Network in East Asia (EANET) are compared with SO 42-, NO 3- and NH 4+ wet deposition model results. Significant correlations appeared between the observation and computed ensemble mean of participant models. Also, differences among modeled sulfur and nitrogen dry depositions have been studied at the EANET sites. Based on the analysis of acid deposition for various species from different models, total depositions of sulfur (SO 2 and sulfate) and nitrogen (nitrate and ammonium) have been evaluated as the ensemble mean of the eight models. In general, all models capture the observed spatial distribution of sulfur and nitrogen deposition, although the absolute values may differ from measurements. High deposition often occurs in eastern China, Japan, the Republic of Korea, Thailand, Vietnam, Philippines and other parts of Southeast Asia. The magnitude of model bias is quite large for many of the models. In examining the reasons for model-measurement disagreement, we find that differences in chemical processes, deposition parameterization, and modeled precipitation are the main reasons for large model disparities.

  12. Testing lowered isothermal models with direct N-body simulations of globular clusters - II. Multimass models

    NASA Astrophysics Data System (ADS)

    Peuten, M.; Zocchi, A.; Gieles, M.; Hénault-Brunet, V.

    2017-09-01

    Lowered isothermal models, such as the multimass Michie-King models, have been successful in describing observational data of globular clusters. In this study, we assess whether such models are able to describe the phase space properties of evolutionary N-body models. We compare the multimass models as implemented in limepy (Gieles & Zocchi) to N-body models of star clusters with different retention fractions for the black holes and neutron stars evolving in a tidal field. We find that multimass models successfully reproduce the density and velocity dispersion profiles of the different mass components in all evolutionary phases and for different remnants retention. We further use these results to study the evolution of global model parameters. We find that over the lifetime of clusters, radial anisotropy gradually evolves from the low- to the high-mass components and we identify features in the properties of observable stars that are indicative of the presence of stellar-mass black holes. We find that the model velocity scale depends on mass as m-δ, with δ ≃ 0.5 for almost all models, but the dependence of central velocity dispersion on m can be shallower, depending on the dark remnant content, and agrees well with that of the N-body models. The reported model parameters, and correlations amongst them, can be used as theoretical priors when fitting these types of mass models to observational data.

  13. Synthesis, spectroscopic characterization, molecular modeling and potentiometric studies of Co(II), Ni(II), Cu(II) and Zn(II) complexes with 1,1-diaminobutane-Schiff base

    NASA Astrophysics Data System (ADS)

    Alaghaz, Abdel-Nasser M. A.

    2014-08-01

    Complexes of cobalt(II), nickel(II), copper(II) and zinc(II) of general composition [M(L)(H2O)2]·2H2O have been synthesized [L = N,N";-bis(2-hydroxybenzylidene)-1,1-diaminobutane]. The elemental analysis, molar conductance measurements, magnetic susceptibility measurements, mass, IR, UV, NMR, SEM, EDX, thermal and EPR spectral studies of the compounds led to the conclusion that the ligand acts as a tetradentate manner. The molar conductance of the complexes in fresh solution of DMSO lies in the range of 7.46-9.13 Ω-1 cm2 mol-1 indicating their non-electrolytic behavior. On the basis of analytical and spectroscopic techniques, octahedral geometry of the complexes was proposed. The Schiff base acts as tetradentate ligand, coordinated through deprotonated phenolic oxygen and azomethine nitrogen atoms. The ligand field parameters were calculated for Co(II), Ni(II) and Cu(II) complexes and their values were found in the range reported for a octahedral structure. The molecular parameters of the ligand and its Co(II), Ni(II), Cu(II) and Zn(II) complexes have been calculated. Protonation constants of Schiff base and stability constants of their binary metal complexes have been determined potentiometrically in 50% DMSO-water media at 25 °C and ionic strength 0.10 M sodium perchlorate.

  14. Removal of Cd(II), Zn(II) and Pb(II) from aqueous solutions by brown marine macro algae: kinetic modelling.

    PubMed

    Freitas, Olga M M; Martins, Ramiro J E; Delerue-Matos, Cristina M; Boaventura, Rui A R

    2008-05-01

    Specific marine macro algae species abundant at the Portuguese coast (Laminaria hyperborea, Bifurcaria bifurcata, Sargassum muticum and Fucus spiralis) were shown to be effective for removing toxic metals (Cd(II), Zn(II) and Pb(II)) from aqueous solutions. The initial metal concentrations in solution were about 75-100 mg L(-1). The observed biosorption capacities for cadmium, zinc and lead ions were in the ranges of 23.9-39.5, 18.6-32.0 and 32.3-50.4 mg g(-1), respectively. Kinetic studies revealed that the metal uptake rate was rather fast, with 75% of the total amount occurring in the first 10 min for all algal species. Experimental data were well fitted by a pseudo-second order rate equation. The contribution of internal diffusion mechanism was significant only to the initial biosorption stage. Results indicate that all the studied macro algae species can provide an efficient and cost-effective technology for eliminating heavy metals from industrial effluents.

  15. Modeling studies of binding of sea raven type II antifreeze protein to ice.

    PubMed

    Wierzbicki, A; Madura, J D; Salmon, C; Sönnichsen, F

    1997-01-01

    Certain plants, insects, and fish living in cold environments prevent tissue damage due to freezing by producing antifreeze proteins or antifreeze glycoproteins that inhibit ice growth below the normal equilibrium freezing point of water in a noncolligative fashion. In polar fish these macromolecules, taking into account their structural characteristics, are grouped into three broad classes, namely Type I, Type II, and Type III. In this paper we report the results of our studies on the stereospecific binding of sea raven, a Type II antifreeze protein (AFP) to (111) hexagonal bipyramidal faces of ice. Earlier studies of Type I and Type III AFPs have shown that stereospecific binding of these proteins, recognizing specific planes of ice, is essential for their noncolligative antifreeze point depression. Moreover, as it has been shown for the AFT of Type I, this binding also occurs along specific vectors on these planes and also is enantioselective, distinguishing between the mirror related directions. In this study we will show, by using molecular modeling, that the fold of Type II AFP could facilitate a stereospecific mode of interaction with (111) planes of ice. Similar to Type I AFP, preferential directionality of binding was also observed in the simulations.

  16. National Aviation Fuel Scenario Analysis Program (NAFSAP). Volume I. Model description. Volume II. User manual. Final report

    SciTech Connect

    Vahovich, S.G.

    1980-03-01

    This report forecasts air carrier jet fuel usage by body type for three user defined markets. The model contains options which allow the user to easily change the composition of the future fleet so that fuel usage scenarios can be 'run'. Both Volumes I and II are contained in this report. Volume I describes the structure of the model. Volume II is a computer users manual.

  17. Photobiomodulation improves cutaneous wound healing in an animal model of type II diabetes.

    PubMed

    Byrnes, Kimberly R; Barna, Lauren; Chenault, V Michelle; Waynant, Ronald W; Ilev, Ilko K; Longo, Leonardo; Miracco, Clelia; Johnson, Bryan; Anders, Juanita J

    2004-08-01

    We investigated the effects of photobiomodulation (PBM) on cutaneous wound healing in an animal model of type II diabetes, Psammomys obesus (Sand Rats). 632-nm light has been established as the most effective wavelength for treatment of cutaneous wounds; however, the inconsistent efficacy of PBM may be due to inadequate treatment parameter selection. Using 632-nm light, an initial series of experiments were done to establish optimal treatment parameters for this model. Following creation of bilateral full-thickness skin wounds, non-diabetic Sand Rats were treated with PBM of differing dosages. Wound healing was assessed according to wound closure and histological characteristics of healing. Optimal treatment parameters were then used to treat type II diabetic Sand Rats while a diabetic control group received no irradiation. In order to elucidate the mechanism behind an improvement in wound healing, expression of basic fibroblast growth factor (bFGF) was assessed. Significant improvement in wound healing histology and wound closure were found following treatment with 4 J/cm(2) (16 mW, 250-sec treatments for 4 consecutive days; p < 0.05). The 4 J/cm(2) dosage significantly improved histology and closure of wounds in the diabetic group in comparison to the non-irradiated diabetic group. Quantitative analysis of bFGF expression at 36 h post-injury revealed a threefold increase in the diabetic and non-diabetic Sand Rats after PBM. The results demonstrate that PBM at an energy density of 4 J/cm(2) is effective in improving the healing of cutaneous wounds in an animal model of type II diabetes, suggesting that PBM (632 nm, 4 J/cm(2)) would be effective in treating chronic cutaneous wounds in diabetic patients.

  18. Modeling Disease Progression: Angiotensin II Indirectly Inhibits Nitric Oxide Production via ADMA Accumulation in Spontaneously Hypertensive Rats

    PubMed Central

    Wang, Haidong; Jiang, Hao; Liu, Haochen; Zhang, Xue; Ran, Guimei; He, Hua; Liu, Xiaoquan

    2016-01-01

    Nitric oxide (NO) production impairment is involved in the onset and development of hypertension. Although NO production impairment in spontaneously hypertensive rat (SHR) has been reported in a variety of researches, the time course of this progressive procedure, as well as its relationship with asymmetric dimethylarginine (ADMA) and angiotensin II (Ang II), has not been quantified. The aim of this research is to establish a mechanism-based disease progression model to assess Ang II and ADMA's inhibition of NO production in SHR's disease progression with/without ramipril's intervention. SHR were randomly divided into three groups: one disease group (n = 8) and two treatment groups (n = 8 for each group): standard treatment group (receiving ramipril 2 mg/kg*day) and intensive treatment group (receiving ramipril 10 mg/kg*day). ADMA, Ang II, NO, and SBP were determined weekly. Intensive treatment with ramipril was found to have no further attenuation of plasma NO and ADMA than standard treatment beyond its significantly stronger antihypertensive effects. Four linked turnover models were developed to characterize the profiles of ADMA, Ang II, NO, and SBP during hypertensive disease progression with/without ramipril intervention. Our model described Ang II and ADMA's contribution to NO production impairment and their responses to ramipril treatment throughout the disease progression in SHR. Model simulations suggested that Ang II affected NO production mainly through inhibiting ADMA elimination rather than affecting nitric oxide synthase (NOS) directly. PMID:27909412

  19. Testing the littlest Higgs model with T-parity at the LHC Run-II

    NASA Astrophysics Data System (ADS)

    Cao, Qing-Hong; Chen, Chuan-Ren; Liu, Yandong

    2016-09-01

    We study the littlest Higgs model with T-parity (LHT) in the process of p p →WH+WH-→W+W-AHAH at the 14 TeV LHC. With the W -jet tagging technique, we demonstrate that the bulk of the model parameter space can be probed at the level of more than 5 σ in the signature of two fat W jets plus large missing energy. Furthermore, we propose a novel strategy of measuring the principle parameter f that is crucial to test the LHT model and to fix mass spectrum, including the dark matter particle. Our proposal can be easily incorporated into the current experimental program of diboson searches at the LHC Run-II.

  20. Time-dependent toroidal compactification proposals and the Bianchi type II model: Classical and quantum solutions

    NASA Astrophysics Data System (ADS)

    Socorro, J.; Toledo Sesma, L.

    2016-03-01

    In this work we construct an effective four-dimensional model by compactifying a ten-dimensional theory of gravity coupled with a real scalar dilaton field on a time-dependent torus without the contributions of fluxes as first approximation. This approach is applied to anisotropic cosmological Bianchi type II model for which we study the classical coupling of the anisotropic scale factors with the two real scalar moduli produced by the compactification process. Also, we present some solutions to the corresponding Wheeler-DeWitt (WDW) equation in the context of Standard Quantum Cosmology and we claim that these quantum solution are generic in the moduli scalar field for all Bianchi Class A models. Also we give the relation to these solutions for asymptotic behavior to large argument in the corresponding quantum solution in the gravitational variables and compare with Bohm's solutions, finding that this corresponds to the lowest-order WKB approximation.

  1. Investigations about Starting Cracks in DC-Casting of 6063-Type Billets Part II: Modelling Results

    NASA Astrophysics Data System (ADS)

    Jensen, E. K.; Schneider, W.

    Influence on starting crack tendency of varying a number of casting parameters has been studied by experiments, Part I (1), and by model calculations, Part II. Both studies point to starting block shape as a most important single factor in controlling starting cracks. By using the thermal model ALSIM-2 in analysing initial experimental results, the variable heat transfer towards the starting block was determined. This made possible a satisfactory model analysis of the starting phase and likewise the formulation of a useful cracking concept. Thus by using calculated and measured liquid pool depth curve in the starting phase of casting as a basis, an effective starting block shape was found. This new shape practically eliminates the starting crack problems in extrusion billets of the AA6063 type alloys.

  2. Anticonvulsant activity of DNS II fraction in the acute seizure models.

    PubMed

    Raza, Muhammad Liaquat; Zeeshan, Mohammad; Ahmad, Manzoor; Shaheen, Farzana; Simjee, Shabana U

    2010-04-21

    Delphinium nordhagenii belongs to family Ranunculaceae, it is widely found in tropical areas of Pakistan. Other species of Delphinium are reported as anticonvulsant and are traditionally used in the treatment of epilepsy. Delphinium nordhagenii is used by local healer in Pakistan but never used for scientific investigation as anticonvulsant. Thus, Delphinium nordhagenii was subjected to bioassay-guided fractionation and the most active fraction, i.e. DNS II acetone was chosen for further testing in the acute seizure models of epilepsy to study the antiepileptic potential in male mice. Different doses (60, 65 and 70mg/kg, i.p.) of DNS II acetone fraction of Delphinium nordhagenii was administered 30min prior the chemoconvulsant's injection in the male mice. Convulsive doses of chemoconvulsants (pentylenetetrazole 90mg/kg, s.c. and picrotoxin 3.15mg/kg, s.c.) were used. The mice were observed 45-90min for the presence of seizures. Moreover, four different doses of DNS II (60, 65, 70 and 100mg/kg, i.p.) were tested in the MES test. The DNS II acetone fraction of Delphinium nordhagenii has exhibited the anticonvulsant actions by preventing the seizures against PTZ- and picrotoxin-induced seizure as well as 100% seizure protection in MES test. The results are comparable with standard AEDs (diazepam 7.5mg/kg, i.p. and phenytoin 20mg/kg, i.p.). These findings suggest that the Delphinium nordhagenii possesses the anticonvulsant activity. Further analysis is needed to confirm the structure and target the extended activity profile. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  3. Chronic kidney disease accelerates cognitive impairment in a mouse model of Alzheimer's disease, through angiotensin II.

    PubMed

    Nakagawa, Takashi; Hasegawa, Yu; Uekawa, Ken; Kim-Mitsuyama, Shokei

    2017-01-01

    Epidemiological studies suggest that chronic kidney disease (CKD) is a significant risk factor in the development of cognitive decline. However, the exact role of CKD in cognitive impairment or dementia is unclear. This work was performed to examine the potential impact of CKD on cognitive impairment in Alzheimer's disease (AD), focusing on angiotensin II. (1) CKD was induced in 5XFAD mice, an AD model mouse, and wild-type mice by feeding an adenine-containing diet and the effect on cognitive function was compared between both strains. There was no significant difference regarding the severity of CKD induced by adenine between the strains. In 5XFAD mice, the CKD group exhibited significant cognitive impairment while the control group (control diet-fed group) did not, as evidenced by a passive avoidance test. On the other hand, in wild-type mice, neither the CKD group nor the control group showed cognitive impairment. Thus, CKD itself appears to accelerate cognitive impairment in AD mice. (2) We also examined the effect of olmesartan, an angiotensin II receptor blocker, on 5XFAD mice with CKD to elucidate the potential involvement of angiotensin II. As evidenced by the findings of the water maze test, olmesartan treatment significantly ameliorated the impairment of spatial learning and memory function induced by CKD in 5XFAD mice. Olmesartan treatment significantly ameliorated blood-brain barrier (BBB) disruption induced by CKD in 5XFAD mice. Furthermore, olmesartan reduced hippocampal oxidative stress in 5XFAD with CKD to similar levels to the control group of 5XFAD fed standard diet. Hence, the amelioration of CKD-induced cognitive impairment in 5XFAD mice by olmesartan appears to be mediated by the suppression of BBB disruption or oxidative stress. In conclusion, we obtained the evidence suggesting that CKD itself accelerates cognitive impairment in AD mice, through angiotensin II. Thus, our work provides a novel insight into the underlying mechanism of the link

  4. FORUM - FutureTox II: In vitro Data and In Silico Models for ...

    EPA Pesticide Factsheets

    FutureTox II, a Society of Toxicology Contemporary Concepts in Toxicology workshop, was held in January, 2014. The meeting goals were to review and discuss the state of the science in toxicology in the context of implementing the NRC 21st century vision of predicting in vivo responses from in vitro and in silico data, and to define the goals for the future. Presentations and discussions were held on priority concerns such as predicting and modeling of metabolism, cell growth and differentiation, effects on sensitive subpopulations, and integrating data into risk assessment. Emerging trends in technologies such as stem cell-derived human cells, 3D organotypic culture models, mathematical modeling of cellular processes and morphogenesis, adverse outcome pathway development, and high-content imaging of in vivo systems were discussed. Although advances in moving towards an in vitro/in silico based risk assessment paradigm were apparent, knowledge gaps in these areas and limitations of technologies were identified. Specific recommendations were made for future directions and research needs in the areas of hepatotoxicity, cancer prediction, developmental toxicity, and regulatory toxicology. This article reports on the outcome of FutureTox II1,2, the second in a series of Society of Toxicology (SOT) Contemporary Concepts in Toxicology (CCT) Workshops, which was attended by invitees and participants from governmental and regulatory agencies, research institutes, academ

  5. Modeling of oxygen transport and cell killing in type-II photodynamic therapy.

    PubMed

    Gkigkitzis, Ioannis; Feng, Yuanming; Yang, Chunmei; Lu, Jun Q; Hu, Xin-Hua

    2012-01-01

    Photodynamic therapy (PDT) provides an effective option for treatment of tumors and other diseases in superficial tissues and attracts attention for in vitro study with cells. In this study, we present a significantly improved model of in vitro cell killing through Type-II PDT for simulation of the molecular interactions and cell killing in time domain in the presence of oxygen transport within a spherical cell. The self-consistency of the approach is examined by determination of conditions for obtaining positive definitive solutions of molecular concentrations. Decay constants of photosensitizers and unoxidized receptors are extracted as the key indices of molecular kinetics with different oxygen diffusion constants and permeability at the cell membrane. By coupling the molecular kinetics to cell killing, we develop a modeling method of PDT cytotoxicity caused by singlet oxygen and obtain the cell survival ratio as a function of light fluence or initial photosensitizer concentration with different photon density or irradiance of incident light and other parameters of oxygen transport. The results show that the present model of Type-II PDT yields a powerful tool to quantitate various events underlying PDT at the molecular and cellular levels and to interpret experimental results of in vitro cell studies. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

  6. National Aviation Fuel Scenario Analysis Program (NAFSAP). Volume I. Model Description. Volume II. User Manual.

    DTIC Science & Technology

    1980-03-01

    TESI CHART NATIONAI RUREAt (F ANDA[)Rt 1V4 A NATIONAL. AVIATION ~ FUEL SCENARIO.. ANALYSIS PROGRAM 49!! VOLUM I: MODEL DESCRIA~v 4<C VOLUME II: tr)ER...O %a 0 CD -00 a0 Dcc% %D Ln n q F u-u - ON 4w - u-u-MN N En -4C u-u-u-u- u- .- u-- - u--4uu 41 4t 1- The second major class of inputs to NAFSAP is the...this option determines the specific form of the number of new purchases (NOBUYS) computation. 14 L " - - .. .... . .I li I I q i . .. . . . . . r I I i

  7. Hierarchical competition models with the Allee effect II: the case of immigration.

    PubMed

    Assas, Laila; Dennis, Brian; Elaydi, Saber; Kwessi, Eddy; Livadiotis, George

    2015-01-01

    This is part II of an earlier paper that dealt with hierarchical models with the Allee effect but with no immigration. In this paper, we greatly simplify the proofs in part I and provide a proof of the global dynamics of the non-hyperbolic cases that were previously conjectured. Then, we show how immigration to one of the species or to both would, drastically, change the dynamics of the system. It is shown that if the level of immigration to one or to both species is above a specified level, then there will be no extinction region where both species go to extinction.

  8. Calcium-manganese oxides as structural and functional models for active site in oxygen evolving complex in photosystem II: lessons from simple models.

    PubMed

    Najafpour, Mohammad Mahdi

    2011-01-01

    The oxygen evolving complex in photosystem II which induces the oxidation of water to dioxygen in plants, algae and certain bacteria contains a cluster of one calcium and four manganese ions. It serves as a model to split water by sunlight. Reports on the mechanism and structure of photosystem II provide a more detailed architecture of the oxygen evolving complex and the surrounding amino acids. One challenge in this field is the development of artificial model compounds to study oxygen evolution reaction outside the complicated environment of the enzyme. Calcium-manganese oxides as structural and functional models for the active site of photosystem II are explained and reviewed in this paper. Because of related structures of these calcium-manganese oxides and the catalytic centers of active site of the oxygen evolving complex of photosystem II, the study may help to understand more about mechanism of oxygen evolution by the oxygen evolving complex of photosystem II.

  9. The Sortie-Generation Model System. Volume II. Sortie-Generation Model User’s Guide,

    DTIC Science & Technology

    1981-09-01

    z cc/ cnU LA.U .C C/)C) I- 1-4 > a. LL. LA-a I-i LI-.. U-- cc...IA LCLL -JA fp 0o - CD . -) ,aA. - -’J Li. -0 -1-5 0 r 0 GG wL LA- LL00 U;LU -I c. - - U La- J I C.)L LLL La..0 Lai J Z Z - 00L U) C) u&a LL. u ’ 2 z ...Lu 2W W x L. U.I 0Z0 W Li) ’Tim-I. - 0. 0 a E 0 0 U) Q 0 m 2 L LI0 u C0 0U r xx X.J 0 N 0 IT 0) I- J u ) M~ 0 o L ZWE wWW Lu 0 M U 1- ) N W x W Z Z

  10. Aerosols at the Poles: An AeroCom Phase II Multi-Model Evaluation

    NASA Astrophysics Data System (ADS)

    Sand, M.; Samset, B. H.

    2016-12-01

    Atmospheric aerosols from anthropogenic and natural sources reach the Polar Regions through long-range transport. By scattering and absorbing solar radiation, aerosols perturb the energy balance in the region and may have played a significant role in recent Arctic warming. Aerosols in Polar regions are however, poorly constrained in present day global climate models. Here we compare aerosol burdens from simulations with 16 global aerosol models from the Aerocom phase II model inter-comparison project with available observations at both Poles. We show that the annual mean multi-model median Aerosol Optical Depth (AOD) is not a bad representation of the measured AOD in Arctic, even though the model spread is large. The models tend to underestimate the spring maximum and overestimate the summer/autumn minimum. We also document the geographical distribution and seasonal cycle of aerosol burdens and shortwave anthropogenic direct radiative forcing (DRF) of the total aerosol and the individual aerosol species; black carbon (BC), sulfate, and primary organic aerosols from fossil/bio fuel and biomass burning, dust and sea-salt. A subset of models has also reported nitrate and secondary organic aerosols. The models produce an annual mean median AOD 0.07 in the Arctic and 0.01 the Antarctic. The Arctic modeled annual mean DRF is slightly negative -0.12 Wm-2, dominated by a positive black carbon DRF during spring and a negative sulfate DRF during summer. We perform sensitivity experiments with one of the Aerocom models (GISS modelE) to investigate how regional emissions of BC and sulfate and the lifetime of BC influence the Arctic and Antarctic aerosol burdens.

  11. Sorption modelling on illite. Part II: Actinide sorption and linear free energy relationships

    NASA Astrophysics Data System (ADS)

    Bradbury, M. H.; Baeyens, B.

    2009-02-01

    Sorption edge data for Ni(II), Co(II), Eu(III) and Sn(IV) [Bradbury M. H. and Baeyens B. (2009) Sorption modelling on illite. Part I: titration measurements and sorption of Ni(II), Co(II), Eu(III) and Sn(IV), Part I] on purified Na-Illite du Puy are available from some previous work, and some new measurements for Am(III), Th(IV), Pa(V) and U(VI) are presented here. All of these sorption edge measurements have been modelled with a 2 site protolysis non-electrostatic surface complexation and cation exchange (2SPNE SC/CE) sorption model for which the site types, site capacities and protolysis constants were fixed [Bradbury M. H. and Baeyens B. (2009), Part I]. In addition, two further data sets for the sorption of Am(III) and Np(V) on Illite du Puy, obtained from the literature, were also modelled in this work. Thus, surface complexation constants for the strong sites in the 2SPNE SC/CE sorption model for nine metals with valence states from II to VI have been obtained. A linear relationship between the logarithm of strong site metal binding constants, SK x-1, and the logarithm of the corresponding aqueous hydrolysis stability constant, OHK x, extending over nearly 35 orders of magnitude is established here for illite for these nine metals. Such correlations are often termed linear free energy relationships (LFER), and although they are quite common in aqueous phase chemistry, they are much less so in surface chemistry, especially over this large range. The LFER for illite could be described by the equation: logSK=7.9±0.4+(0.83±0.02)logOHKx where, " x" is an integer. A similar relationship has been previously obtained for montmorillonite, thus LFERs relating to the sorption on two of the most important clay minerals present in natural systems have been established. Such an LFER approach is an extremely useful tool for estimating surface complexation constants for metals in a chemically consistent manner. It provides a means of obtaining sorption values for

  12. Fracture prediction for the proximal femur using finite element models: Part II--Nonlinear analysis.

    PubMed

    Lotz, J C; Cheal, E J; Hayes, W C

    1991-11-01

    In Part I we reported the results of linear finite element models of the proximal femur generated using geometric and constitutive data collected with quantitative computed tomography. These models demonstrated excellent agreement with in vitro studies when used to predict ultimate failure loads. In Part II, we report our extension of those finite element models to include nonlinear behavior of the trabecular and cortical bone. A highly nonlinear material law, originally designed for representing concrete, was used for trabecular bone, while a bilinear material law was used for cortical bone. We found excellent agreement between the model predictions and in vitro fracture data for both the onset of bone yielding and bone fracture. For bone yielding, the model predictions were within 2 percent for a load which simulated one-legged stance and 1 percent for a load which simulated a fall. For bone fracture, the model predictions were within 1 percent and 17 percent, respectively. The models also demonstrated different fracture mechanisms for the two different loading configurations. For one-legged stance, failure within the primary compressive trabeculae at the subcapital region occurred first, leading to load transfer and, ultimately, failure of the surrounding cortical shell. However, for a fall, failure of the cortical and trabecular bone occurred simultaneously within the intertrochanteric region. These results support our previous findings that the strength of the subcapital region is primarily due to trabecular bone whereas the strength of the intertrochanteric region is primarily due to cortical bone.

  13. Education as Experimentation: A Planned Variation Model. Volume IIIA: Findings: Cohort II; Interim Findings: Cohort III. Volume IIIB: Appendices.

    ERIC Educational Resources Information Center

    Stebbins, Linda B.; And Others

    This segment of the national evaluation study of the Follow Through Planned Variation Model reviews the background of the study, describes 13 of the Follow Through models involved, and presents an analysis of the effects of these models on students. The analysis is based on data from 4 years of Follow Through participation by Cohort II children…

  14. A multimedia fate and chemical transport modeling system for pesticides: II. Model evaluation

    NASA Astrophysics Data System (ADS)

    Li, Rong; Scholtz, M. Trevor; Yang, Fuquan; Sloan, James J.

    2011-07-01

    Pesticides have adverse health effects and can be transported over long distances to contaminate sensitive ecosystems. To address problems caused by environmental pesticides we developed a multimedia multi-pollutant modeling system, and here we present an evaluation of the model by comparing modeled results against measurements. The modeled toxaphene air concentrations for two sites, in Louisiana (LA) and Michigan (MI), are in good agreement with measurements (average concentrations agree to within a factor of 2). Because the residue inventory showed no soil residues at these two sites, resulting in no emissions, the concentrations must be caused by transport; the good agreement between the modeled and measured concentrations suggests that the model simulates atmospheric transport accurately. Compared to the LA and MI sites, the measured air concentrations at two other sites having toxaphene soil residues leading to emissions, in Indiana and Arkansas, showed more pronounced seasonal variability (higher in warmer months); this pattern was also captured by the model. The model-predicted toxaphene concentration fraction on particles (0.5-5%) agrees well with measurement-based estimates (3% or 6%). There is also good agreement between modeled and measured dry (1:1) and wet (within a factor of less than 2) depositions in Lake Ontario. Additionally this study identified erroneous soil residue data around a site in Texas in a published US toxaphene residue inventory, which led to very low modeled air concentrations at this site. Except for the erroneous soil residue data around this site, the good agreement between the modeled and observed results implies that both the US and Mexican toxaphene soil residue inventories are reasonably good. This agreement also suggests that the modeling system is capable of simulating the important physical and chemical processes in the multimedia compartments.

  15. Mechanical, Mathematical, and Computer Modeling in Penetration Mechanics - IV (Hybrid Models for Nanostructured Ceramics - II)

    DTIC Science & Technology

    2006-11-30

    model of penetration of long elastically deformable projectiles into semi- infinite targets 3 Introduction 3 1. Basic model equations of penetration...of non- deformable projectiles into semi-infinite target 4 1.1. Geometrical scheme of penetration model of non- deformable projectile 4 1.2. Velocity...c. 20 1.3. Pulverized region (a < r < b). 22 2. Example 25 III. Investigation of deformation process at high-speed loadings of ceramic materials

  16. Model-predictive control of the Czochralski crystallization process. Part II. Reduced-order convection model

    NASA Astrophysics Data System (ADS)

    Irizarry-Rivera, Roberto; Seider, Warren D.

    1997-07-01

    A new reduced-order model (ROM) is proposed for the bulk-controller presented in Part I. This model considers convection in the melt based upon the assumption of an idealized flow geometry consisting of horizontal donuts and vertical tubes with radial and axial dispersion, respectively. Boundary and bulk layers are assumed to separate the core fluid from the crystal and crucible. Scale analysis and integral boundary-layer theory are utilized to estimate the boundary-layer thicknesses and the maximum stream function in the core fluid. A strategy is presented for adjusting the imperfect model online to reduce the process/model mismatch during MPC.

  17. Modelling the Pan-Spectral Energy Distribution of Starburst Galaxies: III. Emission Line Diagnostics of Ensembles of H II Regions

    SciTech Connect

    Dopita, M A; Fischera, J; Sutherland, R S; Kewley, L J; Leitherer, C; Tuffs, R J; Popescu, C C; van Breugel, W; Groves, B A

    2006-05-10

    We have built, as far as possible, fully self-consistent models of H II regions around aging clusters of stars. These produce strong emission line diagnostics applicable to either individual H II regions in galaxies, or to the integrated emission line spectra of disk or starburst galaxies. The models assume that the expansion and internal pressure of individual H II regions is driven by the net input of mechanical energy from the central cluster, be it through winds or supernova events. This eliminates the ionization parameter as a free variable, replacing it with a parameter which depends on the ratio of the cluster mass to the pressure in the surrounding interstellar medium. These models explain why H II regions with low abundances have high excitation, and demonstrate that at least part of the warm ionized medium is the result of overlapping faint, old, large, and low pressure H II regions. We present a number of line ratios (at both optical and IR wavelengths) that provide reliable abundance diagnostics for either single H II regions or for integrated galaxy spectra, and others that are sensitive to the age of the cluster stars exciting individual H II regions.

  18. Type II Supernova Energetics and Comparison of Light Curves to Shock-Cooling Models

    NASA Technical Reports Server (NTRS)

    Rubin, Adam; Gal-Yam, Avishay; Cia, Annalisa De; Horesh, Assaf; Khazov, Danny; Ofek, Eran O.; Kulkarni, S. R.; Arcavi, Iair; Manulis, Ilan; Cenko, S. Bradley

    2016-01-01

    During the first few days after explosion, Type II supernovae (SNe) are dominated by relatively simple physics. Theoretical predictions regarding early-time SN light curves in the ultraviolet (UV) and optical bands are thus quite robust. We present, for the first time, a sample of 57 R-band SN II light curves that are well-monitored during their rise, with greater than 5 detections during the first 10 days after discovery, and a well-constrained time of explosion to within 13 days. We show that the energy per unit mass (E/M) can be deduced to roughly a factor of five by comparing early-time optical data to the 2011 model of Rabinak Waxman, while the progenitor radius cannot be determined based on R-band data alone. We find that SN II explosion energies span a range of EM = (0.2-20) x 10(exp 51) erg/(10 M stellar mass), and have a mean energy per unit mass of E/ M = 0.85 x 10(exp 51) erg(10 stellar mass), corrected for Malmquist bias. Assuming a small spread in progenitor masses, this indicates a large intrinsic diversity in explosion energy. Moreover, E/M is positively correlated with the amount of Ni-56 produced in the explosion, as predicted by some recent models of core-collapse SNe. We further present several empirical correlations. The peak magnitude is correlated with the decline rate (Delta m(sub15), the decline rate is weakly correlated with the rise time, and the rise time is not significantly correlated with the peak magnitude. Faster declining SNe are more luminous and have longer rise times. This limits the possible power sources for such events.

  19. Type II supernova energetics and comparison of light curves to shock-cooling models

    DOE PAGES

    Rubin, Adam; Gal-Yam, Avishay; De Cia, Annalisa; ...

    2016-03-16

    During the first few days after explosion, Type II supernovae (SNe) are dominated by relatively simple physics. Theoretical predictions regarding early-time SN light curves in the ultraviolet (UV) and optical bands are thus quite robust. We present, for the first time, a sample of 57 R-band SN II light curves that are well-monitored during their rise, withmore » $$\\gt 5$$ detections during the first 10 days after discovery, and a well-constrained time of explosion to within 1–3 days. We show that the energy per unit mass (E/M) can be deduced to roughly a factor of five by comparing early-time optical data to the 2011 model of Rabinak & Waxman, while the progenitor radius cannot be determined based on R-band data alone. We find that SN II explosion energies span a range of E/M = (0.2–20) × 1051 erg/(10 $${M}_{\\odot }$$), and have a mean energy per unit mass of $$\\langle E/M\\rangle =0.85\\times {10}^{51}$$ erg/(10 $${M}_{\\odot }$$), corrected for Malmquist bias. Assuming a small spread in progenitor masses, this indicates a large intrinsic diversity in explosion energy. Moreover, E/M is positively correlated with the amount of 56Ni produced in the explosion, as predicted by some recent models of core-collapse SNe. We further present several empirical correlations. The peak magnitude is correlated with the decline rate ($${\\rm{\\Delta }}{m}_{15}$$), the decline rate is weakly correlated with the rise time, and the rise time is not significantly correlated with the peak magnitude. Faster declining SNe are more luminous and have longer rise times. Lastly, this limits the possible power sources for such events.« less

  20. Modeling of "Stripe" Wave Phenomena Seen by the CHARM II and ACES Sounding Rockets

    NASA Astrophysics Data System (ADS)

    Dombrowski, M. P.; Labelle, J. W.

    2010-12-01

    Two recent sounding-rocket missions—CHARM II and ACES—have been launched from Poker Flat Research Range, carrying the Dartmouth High-Frequency Experiment (HFE) among their primary instruments. The HFE is a receiver system which effectively yields continuous (100% duty cycle) E-field waveform measurements up to 5 MHz. The CHARM II sounding rocket was launched 9:49 UT on 15 February 2010 into a substorm, while the ACES mission consisted of two rockets, launched into quiet aurora at 9:49 and 9:50 UT on 29 January 2009. At approximately 350 km on CHARM II and the ACES High-Flyer, the HFE detected short (~2s) bursts of broadband (200-500 kHz) noise with a 'stripe' pattern of nulls imposed on it. These nulls have 10 to 20 kHz width and spacing, and many show a regular, non-linear frequency-time relation. These events are different from the 'stripes' discussed by Samara and LaBelle [2006] and Colpitts et al. [2010], because of the density of the stripes, the non-linearity, and the appearance of being an absorptive rather than emissive phenomenon. These events are similar to 'stripe' features reported by Brittain et al. [1983] in the VLF range, explained as an interference pattern between a downward-traveling whistler-mode wave and its reflection off the bottom of the ionosphere. Following their analysis method, we modeled our stripes as higher-frequency interfering whistlers reflecting off of a density gradient. This model predicts the near-hyperbolic frequency-time curves and high density of the nulls, and therefore shows promise at explaining the new observations.

  1. Type II Supernova Energetics and Comparison of Light Curves to Shock-cooling Models

    NASA Astrophysics Data System (ADS)

    Rubin, Adam; Gal-Yam, Avishay; De Cia, Annalisa; Horesh, Assaf; Khazov, Danny; Ofek, Eran O.; Kulkarni, S. R.; Arcavi, Iair; Manulis, Ilan; Yaron, Ofer; Vreeswijk, Paul; Kasliwal, Mansi M.; Ben-Ami, Sagi; Perley, Daniel A.; Cao, Yi; Cenko, S. Bradley; Rebbapragada, Umaa D.; Woźniak, P. R.; Filippenko, Alexei V.; Clubb, K. I.; Nugent, Peter E.; Pan, Y.-C.; Badenes, C.; Howell, D. Andrew; Valenti, Stefano; Sand, David; Sollerman, J.; Johansson, Joel; Leonard, Douglas C.; Horst, J. Chuck; Armen, Stephen F.; Fedrow, Joseph M.; Quimby, Robert M.; Mazzali, Paulo; Pian, Elena; Sternberg, Assaf; Matheson, Thomas; Sullivan, M.; Maguire, K.; Lazarevic, Sanja

    2016-03-01

    During the first few days after explosion, Type II supernovae (SNe) are dominated by relatively simple physics. Theoretical predictions regarding early-time SN light curves in the ultraviolet (UV) and optical bands are thus quite robust. We present, for the first time, a sample of 57 R-band SN II light curves that are well-monitored during their rise, with \\gt 5 detections during the first 10 days after discovery, and a well-constrained time of explosion to within 1-3 days. We show that the energy per unit mass (E/M) can be deduced to roughly a factor of five by comparing early-time optical data to the 2011 model of Rabinak & Waxman, while the progenitor radius cannot be determined based on R-band data alone. We find that SN II explosion energies span a range of E/M = (0.2-20) × 1051 erg/(10 {M}⊙ ), and have a mean energy per unit mass of < E/M> =0.85× {10}51 erg/(10 {M}⊙ ), corrected for Malmquist bias. Assuming a small spread in progenitor masses, this indicates a large intrinsic diversity in explosion energy. Moreover, E/M is positively correlated with the amount of 56Ni produced in the explosion, as predicted by some recent models of core-collapse SNe. We further present several empirical correlations. The peak magnitude is correlated with the decline rate ({{Δ }}{m}15), the decline rate is weakly correlated with the rise time, and the rise time is not significantly correlated with the peak magnitude. Faster declining SNe are more luminous and have longer rise times. This limits the possible power sources for such events.

  2. Carbonic anhydrase activity of dinuclear Cu(II) complexes with patellamide model ligands.

    PubMed

    Comba, Peter; Gahan, Lawrence R; Hanson, Graeme R; Maeder, Marcel; Westphal, Michael

    2014-02-28

    The dicopper(II) complexes of six pseudo-octapeptides, synthetic analogues of ascidiacyclamide and the patellamides, found in ascidians of the Pacific and Indian Oceans, are shown to be efficient carbonic anhydrase model complexes with k(cat) up to 7.3 × 10(3) s(-1) (uncatalyzed: 3.7 × 10(-2) s(-1); enzyme-catalyzed: 2 × 10(5)-1.4 × 10(6) s(-1)) and a turnover number (TON) of at least 1700, limited only by the experimental conditions used. So far, no copper-based natural carbonic anhydrases are known, no faster model systems have been described and the biological role of the patellamide macrocycles is so far unknown. The observed CO2 hydration rates depend on the configuration of the isopropyl side chains of the pseudo-octapeptide scaffold, and the naturally observed R*,S*,R*,S* geometry is shown to lead to more efficient catalysts than the S*,S*,S*,S* isomers. The catalytic efficiency also depends on the heterocyclic donor groups of the pseudo-octapeptides. Interestingly, the dicopper(II) complex of the ligand with four imidazole groups is a more efficient catalyst than that of the close analogue of ascidiacyclamide with two thiazole and two oxazoline rings. The experimental observations indicate that the nucleophilic attack of a Cu(II)-coordinated hydroxide at the CO2 carbon center is rate determining, i.e. formation of the catalyst-CO2 adduct and release of carbonate/bicarbonate are relatively fast processes.

  3. Type II supernova energetics and comparison of light curves to shock-cooling models

    SciTech Connect

    Rubin, Adam; Gal-Yam, Avishay; De Cia, Annalisa; Horesh, Assaf; Khazov, Danny; Ofek, Eran O.; Kulkarni, S. R.; Arcavi, Iair; Manulis, Ilan; Yaron, Ofer; Vreeswijk, Paul; Kasliwal, Mansi M.; Ben-Ami, Sagi; Perley, Daniel A.; Cao, Yi; Cenko, S. Bradley; Rebbapragada, Umaa D.; Wozniak, P. R.; Filippenko, Alexei V.; Clubb, K. I.; Nugent, Peter E.; Pan, Y. -C.; Badenes, C.; Howell, D. Andrew; Valenti, Stefano; Sand, David; Sollerman, J.; Johansson, Joel; Leonard, Douglas C.; Horst, J. Chuck; Armen, Stephen F.; Fedrow, Joseph M.; Quimby, Robert M.; Mazzali, Paulo; Pian, Elena; Sternberg, Assaf; Matheson, Thomas; Sullivan, M.; Maguire, K.; Lazarevic, Sanja

    2016-03-16

    During the first few days after explosion, Type II supernovae (SNe) are dominated by relatively simple physics. Theoretical predictions regarding early-time SN light curves in the ultraviolet (UV) and optical bands are thus quite robust. We present, for the first time, a sample of 57 R-band SN II light curves that are well-monitored during their rise, with $\\gt 5$ detections during the first 10 days after discovery, and a well-constrained time of explosion to within 1–3 days. We show that the energy per unit mass (E/M) can be deduced to roughly a factor of five by comparing early-time optical data to the 2011 model of Rabinak & Waxman, while the progenitor radius cannot be determined based on R-band data alone. We find that SN II explosion energies span a range of E/M = (0.2–20) × 1051 erg/(10 ${M}_{\\odot }$), and have a mean energy per unit mass of $\\langle E/M\\rangle =0.85\\times {10}^{51}$ erg/(10 ${M}_{\\odot }$), corrected for Malmquist bias. Assuming a small spread in progenitor masses, this indicates a large intrinsic diversity in explosion energy. Moreover, E/M is positively correlated with the amount of 56Ni produced in the explosion, as predicted by some recent models of core-collapse SNe. We further present several empirical correlations. The peak magnitude is correlated with the decline rate (${\\rm{\\Delta }}{m}_{15}$), the decline rate is weakly correlated with the rise time, and the rise time is not significantly correlated with the peak magnitude. Faster declining SNe are more luminous and have longer rise times. Lastly, this limits the possible power sources for such events.

  4. Improving Generalized Born Models by Exploiting Connections to Polarizable Continuum Models. II. Corrections for Salt Effects.

    PubMed

    Lange, Adrian W; Herbert, John M

    2012-11-13

    A previous analytical investigation of the generalized Born (GB) implicit solvation model is extended to solvents of nonzero ionic strength. The GB model with salt effects (GB-SE) is shown to resemble the Debye-Hückel-like screening model (DESMO), a polarizable continuum model (PCM) that we have recently developed for salty solutions. DESMO may be regarded either as a generalization of the conductor-like PCM (C-PCM) that extends C-PCM to electrolyte solutions or alternatively as a generalization of Debye-Hückel theory to arbitrary cavity shapes. The connection between GB-SE and DESMO suggests how the former can be modified to account for the exclusion of mobile ions from the cavity interior, an effect that is typically absent in GB-SE models. We propose two simple GB-SE models that are exact for a point charge in a spherical cavity and that introduce the ability to account, albeit approximately, for the finite size of the mobile ions. The accuracy of these new models is demonstrated by applications to both model systems and real proteins. These tests also demonstrate the accuracy of the DESMO approach, as compared to more sophisticated PCMs developed for electrolyte solutions.

  5. Mathematics in Marine Botany: Examples of the Modelling Process. Part II: Continuous Models.

    ERIC Educational Resources Information Center

    Nyman, Melvin A.; Brown, Murray T.

    1996-01-01

    Describes some continuous models for growth of the seaweed Macrocystis pyrifera. Uses observed growth rates over several months to derive first-order differential equations as models for growth rates of individual fronds. The nature of the solutions is analyzed and comparison between these theoretical results and documented characteristics of…

  6. Mathematics in Marine Botany: Examples of the Modelling Process. Part II: Continuous Models.

    ERIC Educational Resources Information Center

    Nyman, Melvin A.; Brown, Murray T.

    1996-01-01

    Describes some continuous models for growth of the seaweed Macrocystis pyrifera. Uses observed growth rates over several months to derive first-order differential equations as models for growth rates of individual fronds. The nature of the solutions is analyzed and comparison between these theoretical results and documented characteristics of…

  7. FISPACT-II: An Advanced Simulation System for Activation, Transmutation and Material Modelling

    NASA Astrophysics Data System (ADS)

    Sublet, J.-Ch.; Eastwood, J. W.; Morgan, J. G.; Gilbert, M. R.; Fleming, M.; Arter, W.

    2017-01-01

    Fispact-II is a code system and library database for modelling activation-transmutation processes, depletion-burn-up, time dependent inventory and radiation damage source terms caused by nuclear reactions and decays. The Fispact-II code, written in object-style Fortran, follows the evolution of material irradiated by neutrons, alphas, gammas, protons, or deuterons, and provides a wide range of derived radiological output quantities to satisfy most needs for nuclear applications. It can be used with any ENDF-compliant group library data for nuclear reactions, particle-induced and spontaneous fission yields, and radioactive decay (including but not limited to TENDL-2015, ENDF/B-VII.1, JEFF-3.2, JENDL-4.0u, CENDL-3.1 processed into fine-group-structure files, GEFY-5.2 and UKDD-16), as well as resolved and unresolved resonance range probability tables for self-shielding corrections and updated radiological hazard indices. The code has many novel features including: extension of the energy range up to 1 GeV; additional neutron physics including self-shielding effects, temperature dependence, thin and thick target yields; pathway analysis; and sensitivity and uncertainty quantification and propagation using full covariance data. The latest ENDF libraries such as TENDL encompass thousands of target isotopes. Nuclear data libraries for Fispact-II are prepared from these using processing codes PREPRO, NJOY and CALENDF. These data include resonance parameters, cross sections with covariances, probability tables in the resonance ranges, PKA spectra, kerma, dpa, gas and radionuclide production and energy-dependent fission yields, supplemented with all 27 decay types. All such data for the five most important incident particles are provided in evaluated data tables. The Fispact-II simulation software is described in detail in this paper, together with the nuclear data libraries. The Fispact-II system also includes several utility programs for code-use optimisation

  8. The circumstellar structure of the Be shell star φ Persei. II. Modeling

    NASA Astrophysics Data System (ADS)

    Hummel, W.; Štefl, S.

    2001-03-01

    We model Fe Ii 5317 emission lines and phase resolved He I 6678 and 5876 emission lines of the bright B2e&sdO shell binary phi Per to find the size and shape of the excitation region inside the circumprimary disk. We find the Fe Ii 5317 emission to originate within 9 stellar radii in an axisymmetric disk around the primary. Orbital phase variations of He I 6678 are fit in terms of a disk sector with disk radius of 10 stellar radii and opening angle of =~ 120degr facing the secondary. This region can be alternatively described by an intersection of a sphere around the secondary and the circumprimary disk with a penetration depth of about 7 R_*. Similar fit values are found for He I 5876. The enigmatic orbital phase precedence of shell occurrence in the He I emission features is discussed. We favor a model in which the inner He I shell is deformed because of differential rotation in combination with a finite recombination time. Based on observations collected at the Ondřejov Observatory (of the Academy of Sciences of the Czech Republic), the German-Spanish Astronomical Center (DSAZ) -- Calar Alto (operated by the Max-Plank-Institut für Astronomie Heidelberg jointly with the Spanish National Commission for Astronomy) and Observatoire de Haute-Provence (OHP; CNRS, France).

  9. Radial electric field computations with DKES and neoclassical models in TJ-II stellarator

    NASA Astrophysics Data System (ADS)

    Martinell, Julio; Gutierrez-Tapia, Cesar; Lopez-Bruna, Daniel

    2015-11-01

    Radial electric fields arise due to the non-ambipolar transport in stellarator plasmas and play an important role in determining some improved confinement regimes. In order to calculate this electric field it is necessary to take all particle fluxes that are not ambipolar. The most important contribution to these fluxes comes from neoclassical transport. Here we use particle fluxes obtained from kinetic equation computations using the code DKES to evaluate the radial electric field profiles for certain discharges of the heliac TJ-II. Experimental profiles for the density and temperatures are used together with the diffusion coefficients obtained with DKES. A similar computation of the electric field is performed with three analytical neoclassical models that use an approximation for the magnetic geometry. The ambipolar electric field from the models is compared with the one given by DKES and we find that they are all qualitatively similar. They are also compared with experimental measurements of the electric field obtained with HIBP. It is shown that, although the electric field is reasonably well reproduced by the neoclassical computations, especially in high temperature regimes, the particle fluxes are not. Thus, neoclassical theory provides good Er estimates in TJ-II. Support from CONACyT 152905 and DGAPA IN109115 projects is acknowledged.

  10. Blooms' separation of the final exam of Engineering Mathematics II: Item reliability using Rasch measurement model

    NASA Astrophysics Data System (ADS)

    Fuaad, Norain Farhana Ahmad; Nopiah, Zulkifli Mohd; Tawil, Norgainy Mohd; Othman, Haliza; Asshaari, Izamarlina; Osman, Mohd Hanif; Ismail, Nur Arzilah

    2014-06-01

    In engineering studies and researches, Mathematics is one of the main elements which express physical, chemical and engineering laws. Therefore, it is essential for engineering students to have a strong knowledge in the fundamental of mathematics in order to apply the knowledge to real life issues. However, based on the previous results of Mathematics Pre-Test, it shows that the engineering students lack the fundamental knowledge in certain topics in mathematics. Due to this, apart from making improvements in the methods of teaching and learning, studies on the construction of questions (items) should also be emphasized. The purpose of this study is to assist lecturers in the process of item development and to monitor the separation of items based on Blooms' Taxonomy and to measure the reliability of the items itself usingRasch Measurement Model as a tool. By using Rasch Measurement Model, the final exam questions of Engineering Mathematics II (Linear Algebra) for semester 2 sessions 2012/2013 were analysed and the results will provide the details onthe extent to which the content of the item providesuseful information about students' ability. This study reveals that the items used in Engineering Mathematics II (Linear Algebra) final exam are well constructed but the separation of the items raises concern as it is argued that it needs further attention, as there is abig gap between items at several levels of Blooms' cognitive skill.

  11. Inhibition of new vessel growth in mouse model of laser-induced choroidal neovascularization by adiponectin peptide II

    PubMed Central

    Lyzogubov, Valeriy V.; Tytarenko, Ruslana G.; Thotakura, Sushma; Viswanathan, Tito; Bora, Nalini S.; Bora, Puran S.

    2012-01-01

    We have investigated the effect of adiponectin (APN) peptide II on new vessel growth in mouse model of choroidal neovascularization (CNV) or wet type age-related macular degeneration (AMD). Mice were injected intraperitoneally with APN peptide II, control peptide, or PBS on day 1–7 or day 5–14. APN, AdipoR1, PCNA, and VEGF localization was investigated using confocal microscopy, immunohistochemistry, and RT-PCR. APN peptide II decreased the relative area of FITC-dextran perfused vessels by 4-fold, PCNA expression by 3-fold, and the number of PCNA stained HUVEC and MAVEC cells by 38 and 46%, respectively. We concluded that APN peptide II inhibits CNV size on days 7 and 14 by inhibiting the proliferation of endothelial cells in vivo and in vitro. APN peptide II may have therapeutic potential to inhibit CNV or wet AMD. PMID:19422927

  12. A model of neurovascular coupling and the BOLD response PART II.

    PubMed

    Mathias, E J; Plank, M J; David, T

    2017-04-01

    A mathematical model is developed which describes a signalling mechanism of neurovascular coupling with a model of a pyramidal neuron and its corresponding fMRI BOLD response. In the first part of two papers (Part I) we described the integration of the neurovascular coupling unit extended to include a complex neuron model, which includes the important Na/K ATPase pump, with a model that provides a BOLD signal taking its input from the cerebral blood flow and the metabolic rate of oxygen consumption. We showed that this produced a viable signal in terms of initial dip, positive and negative BOLD signals. In this paper (PART II) our model predicts the variations of the BOLD response due to variations in neuronal activity and indicates that the BOLD signal could be used as an initial biomarker for neuronal dysfunction or variations in the perfusion of blood to the cerebral tissue. We have compared the simulated hypoxic BOLD response to experimental BOLD signals observed in the hippocampus during hypoxia showing good agreement. This approach of combined quantitative modelling of neurovascular coupling response and its BOLD response will enable more specific assessment of a brain region.

  13. Analysis of TOPAZ II and SPACE-R space nuclear power plants using a modified thermionic model

    SciTech Connect

    Habedank, O.D.

    1993-03-01

    Models based on the TDS thermionic diode model were developed for the TOPAZ II and SPACE-R nuclear power systems. Due to computer code limitations inherent in the TDS model, only the TOPAZ II system model ran successfully. Several parameter studies were conducted on the TOPAZ II model. These studies determined system performance and efficiency while varying the following: (1) the coolant flow inlet temperatures; (2) the rate of coolant temperature change; (3) the power profile of the core; and (4) the cesium reservoir temperature. Analysis of the results indicate that the model accurately represented the TOPAZ II system, underestimating published data by 10%. Coolant flow parameter studies indicate that raising coolant flow temperatures up to 100 K higher increases system power by put to 5%. Additional increases in temperature result in gradual performance degradation. Varying the axial power profile of the core from the actual peaked profile to a flat profile results in a negligible 0.3% change in total system performance. The peaked profile used in TOPAZ II produces the highest system efficiency of all the profiles modeled. The cesium pressure study indicates that the system is operating above optimum cesium pressure and that system performance is strongly dependent on cesium pressure. Increasing cesium reservoir temperature above design temperature by 30 K decreases system efficiency by 30%.

  14. Realistic tight-binding model for the electronic structure of II-VI semiconductors

    NASA Astrophysics Data System (ADS)

    Sapra, Sameer; Shanthi, N.; Sarma, D. D.

    2002-11-01

    We analyze the electronic structure of group II-VI semiconductors obtained within linearized muffin-tin-orbital approach in order to arrive at a realistic and minimal tight-binding model, parametrized to provide an accurate description of both valence and conduction bands. It is shown that a nearest-neighbor sp3 d5 model is fairly sufficient to describe the electronic structure of these systems over a wide energy range, obviating the use of any fictitious s* orbital. The obtained hopping parameters obey the universal scaling law proposed by Harrison, ensuring transferability to other systems. Furthermore, we show that certain subtle features in the bonding of these compounds require the inclusion of anion-anion interactions in addition to the nearest-neighbor cation-anion interactions.

  15. Zero-{beta} modeling of coaxial helicity injection in the HIT-II spherical torus

    SciTech Connect

    Bayliss, R. A.; Sovinec, C. R.; Redd, A. J.

    2011-09-15

    Coaxial helicity injection in the HIT-II [A. J. Redd et al., Phys. Plasmas 9, 2006 (2002)] spherical torus is modeled with time-dependent resistive magnetohydrodynamics computations run to steady state for conditions without strong relaxation. Laboratory and computed results on injector current and plasma current agree reasonably well as toroidal magnetic field and injector flux are scaled. The scalings are consistent with a dimensional estimate from the Grad-Shafranov equation that provides a new perspective on a previously published model based on a current-sheet equilibrium and the magnetic pressure required for the ''bubble-burst'' criterion. Numerical solutions of the Grad-Shafranov equation with an assumed current profile also indicate large qualitative changes as the predicted criterion is crossed.

  16. LRS Bianchi type-II string cosmological models in a modified theory of gravitation

    NASA Astrophysics Data System (ADS)

    Kanakavalli, T.; Ananda Rao, G.; Reddy, D. R. K.

    2017-03-01

    This paper is devoted to the investigation of spatially homogeneous anisotropic LRS Bianchi type-II cosmological models with string source in a modified theory of gravitation formulated by Harko et al. (Phys. Rev. D 84:024020, 2011) which is universally known as f( R, T) gravity. Here R is the Ricci scalar and T is the trace of the energy momentum tensor. By solving the field equation we have presented massive string and Takabyasi or p-string models in this theory. However it is interesting to note that geometric string in this space-time does not exist in this theory. Physical and geometrical properties of the strings obtained are also discussed.

  17. Canine prostate models in preclinical studies of minimally invasive interventions: part II, benign prostatic hyperplasia models

    PubMed Central

    Báez-Díaz, Claudia; Sánchez-Margallo, Francisco Miguel

    2017-01-01

    Canine prostate is widely used as animal model in the preclinical evaluation of emerging therapeutic interventions. Spontaneous benign prostatic hyperplasia (BPH) is common in adult intact male dogs with two distinct pathological types: glandular and complex form of prostatic hyperplasia. The complex form of prostatic hyperplasia, usually occurring in older dogs, represents an ideal model because of its unique pathologic feature, including not only glandular hyperplasia but also an increase in prostate stromal components. The limited commercial availability of adult dogs with spontaneous BPH motivates experimentally induced BPH in young dogs. Hormone-induced canine BPH model has been well established with various hormonal treatment regimens and administration approaches. The goal of this review is to provide the veterinary background in spontaneous BPH in dogs, summarize the techniques in hormonal induction of canine BPH, and highlight the pathological and clinical limitations of the canine models that may lead to distinct therapeutic responses compared to clinical trials in humans. PMID:28725598

  18. HIERARCHICAL METHODOLOGY FOR MODELING HYDROGEN STORAGE SYSTEMS PART II: DETAILED MODELS

    SciTech Connect

    Hardy, B; Donald L. Anton, D

    2008-12-22

    There is significant interest in hydrogen storage systems that employ a media which either adsorbs, absorbs or reacts with hydrogen in a nearly reversible manner. In any media based storage system the rate of hydrogen uptake and the system capacity is governed by a number of complex, coupled physical processes. To design and evaluate such storage systems, a comprehensive methodology was developed, consisting of a hierarchical sequence of models that range from scoping calculations to numerical models that couple reaction kinetics with heat and mass transfer for both the hydrogen charging and discharging phases. The scoping models were presented in Part I [1] of this two part series of papers. This paper describes a detailed numerical model that integrates the phenomena occurring when hydrogen is charged and discharged. A specific application of the methodology is made to a system using NaAlH{sub 4} as the storage media.

  19. Modeling of surface myoelectric signals--Part II: Model-based signal interpretation.

    PubMed

    Merletti, R; Roy, S H; Kupa, E; Roatta, S; Granata, A

    1999-07-01

    Experimental electromyogram (EMG) data from the human biceps brachii were simulated using the model described in [10] of this work. A multichannel linear electrode array, spanning the length of the biceps, was used to detect monopolar and bipolar signals, from which double differential signals were computed, during either voluntary or electrically elicited isometric contractions. For relatively low-level voluntary contractions (10%-30% of maximum force) individual firings of three to four-different motor units were identified and their waveforms were closely approximated by the model. Motor unit parameters such as depth, size, fiber orientation and length, location of innervation and tendonous zones, propagation velocity, and source width were estimated using the model. Two applications of the model are described. The first analyzes the effects of electrode rotation with respect to the muscle fiber direction and shows the possibility of conduction velocity (CV) over- and under-estimation. The second focuses on the myoelectric manifestations of fatigue during a sustained electrically elicited contraction and the interrelationship between muscle fiber CV, spectral and amplitude variables, and the length of the depolarization zone. It is concluded that a) surface EMG detection using an electrode array, when combined with a model of signal propagation, provides a useful method for understanding the physiological and anatomical determinants of EMG waveform characteristics and b) the model provides a way for the interpretation of fatigue plots.

  20. Modeling FAMA ion beam diagnostics based on the Ptolemy II model

    NASA Astrophysics Data System (ADS)

    Balvanović, R.; Beličev, P.; Radjenović, B.

    2012-10-01

    The previously developed model of ion beam transport control of the FAMA facility is further enhanced by equipping it with the model of ion beam diagnostics. The model of control, executing once, is adjusted so that it executes in iterative mode, where each iteration samples the input beam normally distributed over initial phase space and calculates a single trajectory through the facility beam lines. The model takes into account only the particles that manage to pass through all the beam line apertures, emulating in this way a Faraday cup and a beam profile meter. Generated are also beam phase space distributions and horizontal and vertical beam profiles at the end of the beam transport lines the FAMA facility consists of. By adding the model of ion beam diagnostics to the model of ion beam transport control, the process of determining optimal ion beam control parameters is eased and speeded up, and the understanding of influence of control parameters on the ion beam characteristics is improved.

  1. An improved model of H II bubbles during the epoch of reionization

    NASA Astrophysics Data System (ADS)

    Paranjape, Aseem; Choudhury, T. Roy

    2014-08-01

    The size distribution of ionized regions during the epoch of reionization - a key ingredient in understanding the H I power spectrum observable by 21 cm experiments - can be modelled analytically using the excursion set formalism of random walks in the smoothed initial density field. To date, such calculations have been based on simplifying assumptions carried forward from the earliest excursion set models of two decades ago. In particular, these models assume that the random walks have uncorrelated steps and that haloes can form at arbitrary locations in the initial density field. We extend these calculations by incorporating recent technical developments that allow us to (a) include the effect of correlations in the steps of the walks induced by a realistic smoothing filter and (b) more importantly, account for the fact that dark matter haloes preferentially form near peaks in the initial density. A comparison with previous calculations shows that including these features, particularly the peaks constraint on halo locations, has large effects on the size distribution of the H II bubbles surrounding these haloes. For example, when comparing models at the same value of the globally averaged ionized volume fraction, the typical bubble sizes predicted by our model are more than a factor of 2 larger than earlier calculations. Our results can potentially have a significant impact on estimates of the observable H I power spectrum.

  2. A kinetic model for type I and II IP3R accounting for mode changes.

    PubMed

    Siekmann, Ivo; Wagner, Larry E; Yule, David; Crampin, Edmund J; Sneyd, James

    2012-08-22

    Based upon an extensive single-channel data set, a Markov model for types I and II inositol trisphosphate receptors (IP(3)R) is developed. The model aims to represent accurately the kinetics of both receptor types of IP(3)R depending on the concentrations of inositol trisphosphate (IP(3)), adenosine trisphosphate (ATP), and intracellular calcium (Ca(2+)). In particular, the model takes into account that for some combinations of ligands the IP(3)R switches between extended periods of inactivity alternating with intervals of bursting activity (mode changes). In a first step, the inactive and active modes are modeled separately. It is found that, within modes, both receptor types are ligand-independent. In a second step, the submodels are connected by transition rates. Ligand-dependent regulation of the channel activity is achieved by modulating these transitions between active and inactive modes. As a result, a compact representation of the IP(3)R is obtained that accurately captures stochastic single-channel dynamics including mode changes in a model with six states and 10 rate constants, only two of which are ligand-dependent.

  3. Quantum groups as generalized gauge symmetries in WZNW models. Part II. The quantized model

    NASA Astrophysics Data System (ADS)

    Hadjiivanov, L.; Furlan, P.

    2017-07-01

    This is the second part of a paper dealing with the "internal" (gauge) symmetry of the Wess-Zumino-Novikov-Witten (WZNW) model on a compact Lie group G. It contains a systematic exposition, for G = SU( n), of the canonical quantization based on the study of the classical model (performed in the first part) following the quantum group symmetric approach first advocated by L.D. Faddeev and collaborators. The internal symmetry of the quantized model is carried by the chiral WZNW zero modes satisfying quadratic exchange relations and an n-linear determinant condition. For generic values of the deformation parameter the Fock representation of the zero modes' algebra gives rise to a model space of U q ( sl( n)). The relevant root of unity case is studied in detail for n = 2 when a "restricted" (finite dimensional) quotient quantum group is shown to appear in a natural way. The module structure of the zero modes' Fock space provides a specific duality with the solutions of the Knizhnik-Zamolodchikov equation for the four point functions of primary fields suggesting the existence of an extended state space of logarithmic CFT type. Combining left and right zero modes (i.e., returning to the 2 D model), the rational CFT structure shows up in a setting reminiscent to covariant quantization of gauge theories in which the restricted quantum group plays the role of a generalized gauge symmetry.

  4. Propeller aircraft interior noise model. II - Scale-model and flight-test comparisons

    NASA Technical Reports Server (NTRS)

    Willis, C. M.; Mayes, W. H.

    1987-01-01

    A program for predicting the sound levels inside propeller driven aircraft arising from sidewall transmission of airborne exterior noise is validated through comparisons of predictions with both scale-model test results and measurements obtained in flight tests on a turboprop aircraft. The program produced unbiased predictions for the case of the scale-model tests, with a standard deviation of errors of about 4 dB. For the case of the flight tests, the predictions revealed a bias of 2.62-4.28 dB (depending upon whether or not the data for the fourth harmonic were included) and the standard deviation of the errors ranged between 2.43 and 4.12 dB. The analytical model is shown to be capable of taking changes in the flight environment into account.

  5. Final Report for Dynamic Models for Causal Analysis of Panel Data. Models for Change in Quantitative Variables, Part II Scholastic Models. Part II, Chapter 4.

    ERIC Educational Resources Information Center

    Hannan, Michael T.

    This document is part of a series of chapters described in SO 011 759. Stochastic models for the sociological analysis of change and the change process in quantitative variables are presented. The author lays groundwork for the statistical treatment of simple stochastic differential equations (SDEs) and discusses some of the continuities of…

  6. Domain structure and three-dimensional model of a group II intron-encoded reverse transcriptase

    PubMed Central

    BLOCKER, FORREST J.H.; MOHR, GEORG; CONLAN, LORI H.; QI, LI; BELFORT, MARLENE; LAMBOWITZ, ALAN M.

    2005-01-01

    Group II intron-encoded proteins (IEPs) have both reverse transcriptase (RT) activity, which functions in intron mobility, and maturase activity, which promotes RNA splicing by stabilizing the catalytically active RNA structure. The LtrA protein encoded by the Lactococcus lactis Ll.LtrB group II intron contains an N-terminal RT domain, with conserved sequence motifs RT1 to 7 found in the fingers and palm of retroviral RTs; domain X, associated with maturase activity; and C-terminal DNA-binding and DNA endonuclease domains. Here, partial proteolysis of LtrA with trypsin and Arg-C shows major cleavage sites in RT1, and between the RT and X domains. Group II intron and related non-LTR retroelement RTs contain an N-terminal extension and several insertions relative to retroviral RTs, some with conserved features implying functional importance. Sequence alignments, secondary-structure predictions, and hydrophobicity profiles suggest that domain X is related structurally to the thumb of retroviral RTs. Three-dimensional models of LtrA constructed by “threading” the aligned sequence on X-ray crystal structures of HIV-1 RT (1) account for the proteolytic cleavage sites; (2) suggest a template–primer binding track analogous to that of HIV-1 RT; and (3) show that conserved regions in splicing-competent LtrA variants include regions of the RT and X (thumb) domains in and around the template–primer binding track, distal regions of the fingers, and patches on the protein’s back surface. These regions potentially comprise an extended RNA-binding surface that interacts with different regions of the intron for RNA splicing and reverse transcription. PMID:15574519

  7. Multiscale modeling, simulations, and experiments of coating growth on nanofibers. Part II. Deposition

    NASA Astrophysics Data System (ADS)

    Buldum, A.; Clemons, C. B.; Dill, L. H.; Kreider, K. L.; Young, G. W.; Zheng, X.; Evans, E. A.; Zhang, G.; Hariharan, S. I.

    2005-08-01

    This work is Part II of an integrated experimental/modeling investigation of a procedure to coat nanofibers and core-clad nanostructures with thin-film materials using plasma-enhanced physical vapor deposition. In the experimental effort, electrospun polymer nanofibers are coated with aluminum materials under different operating conditions to observe changes in the coating morphology. This procedure begins with the sputtering of the coating material from a target. Part I [J. Appl. Phys. 98, 044303 (2005)] focused on the sputtering aspect and transport of the sputtered material through the reactor. That reactor level model determines the concentration field of the coating material. This field serves as input into the present species transport and deposition model for the region surrounding an individual nanofiber. The interrelationships among processing factors for the transport and deposition are investigated here from a detailed modeling approach that includes the salient physical and chemical phenomena. Solution strategies that couple continuum and atomistic models are used. At the continuum scale, transport dynamics near the nanofiber are described. At the atomic level, molecular dynamics (MD) simulations are used to study the deposition and sputtering mechanisms at the coating surface. Ion kinetic energies and fluxes are passed from the continuum sheath model to the MD simulations. These simulations calculate sputtering and sticking probabilities that in turn are used to calculate parameters for the continuum transport model. The continuum transport model leads to the definition of an evolution equation for the coating-free surface. This equation is solved using boundary perturbation and level set methods to determine the coating morphology as a function of operating conditions.

  8. Multiscale modeling, simulations, and experiments of coating growth on nanofibers. Part II. Deposition

    SciTech Connect

    Buldum, A.; Clemons, C.B.; Dill, L.H.; Kreider, K.L.; Young, G.W.; Zheng, X.; Evans, E.A.; Zhang, G.; Hariharan, S.I.

    2005-08-15

    This work is Part II of an integrated experimental/modeling investigation of a procedure to coat nanofibers and core-clad nanostructures with thin-film materials using plasma-enhanced physical vapor deposition. In the experimental effort, electrospun polymer nanofibers are coated with aluminum materials under different operating conditions to observe changes in the coating morphology. This procedure begins with the sputtering of the coating material from a target. Part I [J. Appl. Phys. 98, 044303 (2005)] focused on the sputtering aspect and transport of the sputtered material through the reactor. That reactor level model determines the concentration field of the coating material. This field serves as input into the present species transport and deposition model for the region surrounding an individual nanofiber. The interrelationships among processing factors for the transport and deposition are investigated here from a detailed modeling approach that includes the salient physical and chemical phenomena. Solution strategies that couple continuum and atomistic models are used. At the continuum scale, transport dynamics near the nanofiber are described. At the atomic level, molecular dynamics (MD) simulations are used to study the deposition and sputtering mechanisms at the coating surface. Ion kinetic energies and fluxes are passed from the continuum sheath model to the MD simulations. These simulations calculate sputtering and sticking probabilities that in turn are used to calculate parameters for the continuum transport model. The continuum transport model leads to the definition of an evolution equation for the coating-free surface. This equation is solved using boundary perturbation and level set methods to determine the coating morphology as a function of operating conditions.

  9. MODELING THE NUCLEAR INFRARED SPECTRAL ENERGY DISTRIBUTION OF TYPE II ACTIVE GALACTIC NUCLEI

    SciTech Connect

    Lira, Paulina; Videla, Liza; Wu, Yanling; Alonso-Herrero, Almudena; Alexander, David M.; Ward, Martin

    2013-02-20

    We present results from model fitting to the spectral energy distribution (SED) of a homogeneous sample of Seyfert II galaxies drawn from the 12 {mu}m Galaxy Sample. Imaging and nuclear flux measurements are presented in an accompanying paper. Here we add Spitzer/IRS observations to further constrain the SEDs after careful subtraction of a starburst component. We use the library of CLUMPY torus models from Nenkova et al. and also test the two-phase models recently produced by Stalevski et al. We find that photometric and spectroscopic observations in the mid-IR ({lambda} {approx}> 5 {mu}m) are crucial to properly constrain the best-fit torus models. About half of our sources show clear near-IR excess of their SEDs above the best-fit models. This problem can be less severe when using the Stalevski et al. models. The nature of this emission is not clear since best-fitted blackbody temperatures are very high ({approx}1700-2500 K) and the Type II classification of our sources would correspond to a small probability to peer directly into the hottest regions of the torus. Crucially, the derived torus parameters are quite robust when using CLUMPY models, independently of whether or not the sources require an additional blackbody component. Our findings suggest that tori are characterized by N{sub 0}{approx}>5, {sigma} {approx}> 40, {tau} {approx}< 25, Angle i {approx}> 40 Degree-Sign , Y {approx}< 50, and A {sup los} {sub v} {approx} 100-300, where N{sub 0} is the number of clouds in the equatorial plane of the torus, {sigma} is the characteristic opening angle of the cloud distribution, {tau} is the opacity of a single cloud, Angle i is the line-of-sight orientation of the torus, Y is the ratio of the inner to the outer radii, and A {sup los} {sub v} is the total opacity along the line of sight. From these, we can determine typical torus sizes and masses of 0.1-5.0 pc and 10{sup 4}-10{sup 6} M {sub Sun }, respectively. We find tentative evidence that those nuclei with

  10. A dynamic, embedded Lagrangian model for ocean climate models, Part II: Idealised overflow tests

    NASA Astrophysics Data System (ADS)

    Bates, Michael L.; Griffies, Stephen M.; England, Matthew H.

    2012-12-01

    Dense gravity current overflows occur in several regions throughout the world and are an important process in the meridional overturning circulation. Overflows are poorly represented in coarse resolution level coordinate ocean climate models. Here, the embedded Lagrangian model formulated in the companion paper of Bates et al. (2012) is used in two idealised test cases to examine the effect on the representation of dense gravity driven plumes, as well as the effect on the circulation of the bulk ocean in the Eulerian model. The results are compared with simulations with no parameterisation for overflows, as well as simulations that use traditional hydrostatic overflow schemes. The use of Lagrangian "blobs" is shown to improve three key characteristics that are poorly represented in coarse resolution level coordinate models: (1) the depth of the plume, (2) the along slope velocity of the plume, and (3) the response of the bulk ocean to the bottom boundary layer. These improvements are associated with the more appropriate set of dynamics satisfied by the blobs, leading to a more physically sound representation. Experiments are also conducted to examine sensitivity to blob parameters. The blob parameters are examined over a large parameter space.

  11. Kinetic modeling of a multiple immobilized enzyme system. Ii. Application of the model

    SciTech Connect

    Mercer, D.G.; O'Driscoll, K.F.

    1981-11-01

    The mathematical model for the reaction sequence catalyzed by immobilized invertase and glucose oxidase discussed in the preceding article has been used successfully to duplicate experimental findings. In addition, it has been used as a tool for the simulation and prediction of effects derived from alterations to system-related and gel-related parameters. The effects of gel diffusivity on the overall conversion of sucrose substrate to reaction products was investigated through use of this model. Changes in the enzyme loading within a gel and the results of varying the ratio of invertase activity to glucose activity were also evaluated. Through use of concentrations of the molecular species determined at the collocation points within a gel particle and in the bulk liquid phase, an estimate of the thickness of the diffusion boundary layer around the gel particle was determined which was in close agreement with values obtained from classical mass transfer relationships. For most of this study, the enzymes were coimmobilized within the same polymeric matrix. However, a number of tests were run with the enzymes immobilized individually and placed in separate reactors in a sequential reactor system. The experimental results from these tests were duplicated successfully by means of the model with little modification to the basic computer program. Such an example illustrates the potential flexibility of the model and its overall versatility. (Refs. 5).

  12. MODELING THE NEAR-UV BAND OF GK STARS. II. NON-LTE MODELS

    SciTech Connect

    Ian Short, C.; Campbell, Eamonn A.; Pickup, Heather; Hauschildt, Peter H. E-mail: yeti@hs.uni-hamburg.de

    2012-03-10

    We present a grid of atmospheric models and synthetic spectral energy distributions (SEDs) for late-type dwarfs and giants of solar and 1/3 solar metallicity with many opacity sources computed in self-consistent non-local thermodynamic equilibrium (NLTE), and compare them to the LTE grid of Short and Hauschildt (Paper I). We describe, for the first time, how the NLTE treatment affects the thermal equilibrium of the atmospheric structure (T({tau}) relation) and the SED as a finely sampled function of T{sub eff}, log g, and [A/H] among solar metallicity and mildly metal-poor red giants. We compare the computed SEDs to the library of observed spectrophotometry described in Paper I across the entire visible band, and in the blue and red regions of the spectrum separately. We find that for the giants of both metallicities, the NLTE models yield best-fit T{sub eff} values that are 30-90 K lower than those provided by LTE models, while providing greater consistency between log g values, and, for Arcturus, T{sub eff} values, fitted separately to the blue and red spectral regions. There is marginal evidence that NLTE models give more consistent best-fit T{sub eff} values between the red and blue bands for earlier spectral classes among the solar metallicity GK giants than they do for the later classes, but no model fits the blue-band spectrum well for any class. For the two dwarf spectral classes that we are able to study, the effect of NLTE on derived parameters is less significant. We compare our derived T{sub eff} values to several other spectroscopic and photometric T{sub eff} calibrations for red giants, including one that is less model dependent based on the infrared flux method (IRFM). We find that the NLTE models provide slightly better agreement to the IRFM calibration among the warmer stars in our sample, while giving approximately the same level of agreement for the cooler stars.

  13. Testing spectral models for stellar populations with star clusters - II. Results

    NASA Astrophysics Data System (ADS)

    González Delgado, Rosa M.; Cid Fernandes, Roberto

    2010-04-01

    High spectral resolution evolutionary synthesis models have become a routinely used ingredient in extragalactic work, and as such deserve thorough testing. Star clusters are ideal laboratories for such tests. This paper applies the spectral fitting methodology outlined in Paper I to a sample of clusters, mainly from the Magellanic Clouds and spanning a wide range in age and metallicity, fitting their integrated light spectra with a suite of modern evolutionary synthesis models for single stellar populations. The combinations of model plus spectral library employed in this investigation are Galaxev/STELIB, Vazdekis/MILES, SED@/GRANADA and Galaxev/MILES+GRANADA, which provide a representative sample of models currently available for spectral fitting work. A series of empirical tests are performed with these models, comparing the quality of the spectral fits and the values of age, metallicity and extinction obtained with each of them. A comparison is also made between the properties derived from these spectral fits and literature data on these nearby, well studied clusters. These comparisons are done with the general goal of providing useful feedback for model makers, as well as guidance to the users of such models. We find the following. (i) All models are able to derive ages that are in good agreement both with each other and with literature data, although ages derived from spectral fits are on average slightly older than those based on the S-colour-magnitude diagram (S-CMD) method as calibrated by Girardi et al. (ii) There is less agreement between the models for the metallicity and extinction. In particular, Galaxev/STELIB models underestimate the metallicity by ~0.6 dex, and the extinction is overestimated by 0.1 mag. (iii) New generations of models using the GRANADA and MILES libraries are superior to STELIB-based models both in terms of spectral fit quality and regarding the accuracy with which age and metallicity are retrieved. Accuracies of about 0.1 dex in

  14. Design of Training Systems, Phase II Report, Volume II; Detailed Model Descriptions. TAEG Report No. 12-2.

    ERIC Educational Resources Information Center

    Naval Training Equipment Center, Orlando, FL. Training Analysis and Evaluation Group.

    The Design of Training Systems (DOTS) project was initiated by the Department of Defense (DOD) to develop tools for the effective management of military training organizations. Phase 2 involved the design and development of three computer-based mathematical models, described in detail in this report. The models described are the System…

  15. Emergency Response Equipment and Related Training: Airborne Radiological Computer System (Model II)

    SciTech Connect

    David P. Colton

    2007-02-28

    The materials included in the Airborne Radiological Computer System, Model-II (ARCS-II) were assembled with several considerations in mind. First, the system was designed to measure and record the airborne gamma radiation levels and the corresponding latitude and longitude coordinates, and to provide a first overview look of the extent and severity of an accident's impact. Second, the portable system had to be light enough and durable enough that it could be mounted in an aircraft, ground vehicle, or watercraft. Third, the system must control the collection and storage of the data, as well as provide a real-time display of the data collection results to the operator. The notebook computer and color graphics printer components of the system would only be used for analyzing and plotting the data. In essence, the provided equipment is composed of an acquisition system and an analysis system. The data can be transferred from the acquisition system to the analysis system at the end of the data collection or at some other agreeable time.

  16. Modeling char oxidation behavior under Zone II burning conditions at elevated pressures

    SciTech Connect

    Ma, L.Q.; Mitchell, R.

    2009-01-15

    For accurate modeling of the coal combustion process at elevated pressures, account must be made for variations in char-particle structure. As pressure is increased, particle swelling increases during the devolatilization of certain bituminous coals, yielding a variety of char-particle structures, from uniform high-density particles to thin-walled non-uniform low-density particles having large internal void volumes. Since under Zone II burning conditions the char conversion rate depends upon the accessibility of the internal surfaces, the char structure plays a key role in determining particle burnout times. In our approach to characterize the impact of char structure on particle burning rates, effectiveness factors appropriate for thin-walled cenospherical particles and thick-walled particles having a few large cavities are defined and related to the effectiveness factor for uniform high-density particles that have no large voids, only a random distribution of pores having a mean pore size in the sub-micron range. For the uniform case, the Thiele modulus approach is used to account for Zone 11 type burning in which internal burning is limited by the combined effects of pore diffusion and the intrinsic chemical reactivity of the carbonaceous material. In the paper, the impact of having a variety of char structures in a mix of particles burning under Zone II burning conditions is demonstrated.

  17. Atomistic modeling of structure II gas hydrate mechanics: Compressibility and equations of state

    NASA Astrophysics Data System (ADS)

    Vlasic, Thomas M.; Servio, Phillip; Rey, Alejandro D.

    2016-08-01

    This work uses density functional theory (DFT) to investigate the poorly characterized structure II gas hydrates, for various guests (empty, propane, butane, ethane-methane, propane-methane), at the atomistic scale to determine key structure and mechanical properties such as equilibrium lattice volume and bulk modulus. Several equations of state (EOS) for solids (Murnaghan, Birch-Murnaghan, Vinet, Liu) were fitted to energy-volume curves resulting from structure optimization simulations. These EOS, which can be used to characterize the compressional behaviour of gas hydrates, were evaluated in terms of their robustness. The three-parameter Vinet EOS was found to perform just as well if not better than the four-parameter Liu EOS, over the pressure range in this study. As expected, the Murnaghan EOS proved to be the least robust. Furthermore, the equilibrium lattice volumes were found to increase with guest size, with double-guest hydrates showing a larger increase than single-guest hydrates, which has significant implications for the widely used van der Waals and Platteeuw thermodynamic model for gas hydrates. Also, hydrogen bonds prove to be the most likely factor contributing to the resistance of gas hydrates to compression; bulk modulus was found to increase linearly with hydrogen bond density, resulting in a relationship that could be used predictively to determine the bulk modulus of various structure II gas hydrates. Taken together, these results fill a long existing gap in the material chemical physics of these important clathrates.

  18. The role of myosin II in glioma invasion: A mathematical model

    PubMed Central

    Lee, Wanho; Lim, Sookkyung; Kim, Yangjin

    2017-01-01

    Gliomas are malignant tumors that are commonly observed in primary brain cancer. Glioma cells migrate through a dense network of normal cells in microenvironment and spread long distances within brain. In this paper we present a two-dimensional multiscale model in which a glioma cell is surrounded by normal cells and its migration is controlled by cell-mechanical components in the microenvironment via the regulation of myosin II in response to chemoattractants. Our simulation results show that the myosin II plays a key role in the deformation of the cell nucleus as the glioma cell passes through the narrow intercellular space smaller than its nuclear diameter. We also demonstrate that the coordination of biochemical and mechanical components within the cell enables a glioma cell to take the mode of amoeboid migration. This study sheds lights on the understanding of glioma infiltration through the narrow intercellular spaces and may provide a potential approach for the development of anti-invasion strategies via the injection of chemoattractants for localization. PMID:28166231

  19. Use of amino acids as counterions improves the solubility of the BCS II model drug, indomethacin.

    PubMed

    ElShaer, Amr; Khan, Sheraz; Perumal, Dhaya; Hanson, Peter; Mohammed, Afzal R

    2011-07-01

    The number of new chemical entities (NCE) is increasing every day after the introduction of combinatorial chemistry and high throughput screening to the drug discovery cycle. One third of these new compounds have aqueous solubility less than 20µg/mL [1]. Therefore, a great deal of interest has been forwarded to the salt formation technique to overcome solubility limitations. This study aims to improve the drug solubility of a Biopharmaceutical Classification System class II (BCS II) model drug (Indomethacin; IND) using basic amino acids (L-arginine, L-lysine and L-histidine) as counterions. Three new salts were prepared using freeze drying method and characterised by FT-IR spectroscopy, proton nuclear magnetic resonance ((1)HNMR), Differential Scanning Calorimetry (DSC) and Thermogravimetric analysis (TGA). The effect of pH on IND solubility was also investigated using pH-solubility profile. Both arginine and lysine formed novel salts with IND, while histidine failed to dissociate the free acid and in turn no salt was formed. Arginine and lysine increased IND solubility by 10,000 and 2296 fold, respectively. An increase in dissolution rate was also observed for the novel salts. Since these new salts have improved IND solubility to that similar to BCS class I drugs, IND salts could be considered for possible waivers of bioequivalence.

  20. A single H II region model of the strong interstellar scattering towards Sgr A*

    NASA Astrophysics Data System (ADS)

    Sicheneder, Egid; Dexter, Jason

    2017-05-01

    Until recently, the strong interstellar scattering observed towards the Galactic centre (GC) black hole, Sgr A*, was thought to come from dense gas within the GC region. The pulse broadening towards the transient magnetar SGR J1745-2900 near Sgr A* has shown that the source of the scattering is instead located much closer to Earth, possibly in a nearby spiral arm. We show that a single H II region along the line of sight, 1.5-4.8 kpc away from Earth with density ne of a few ≃ 100 cm^{-3} and radius R ≃ 1.8-3.2 pc can explain the observed angular broadening of Sgr A*. Clouds closer to the GC overproduce the observed disperson measure, providing an independent location constraint that agrees with that from the magnetar pulse broadening. Our model predicts that sources within ≲10 pc should show the same scattering origin as the magnetar and Sgr A*, while the nearest known pulsars with separations >20 pc should not. The radio spectrum of Sgr A* should show a cut-off from free-free absorption at 0.2 ≲ ν ≲ 1 GHz. For a magnetic field strength B ≃ 15-70 μG, the H II region could produce the rotation measure of the magnetar, the largest of any known pulsar, without requiring the gas near Sgr A* to be strongly magnetized.

  1. Atomistic modeling of structure II gas hydrate mechanics: Compressibility and equations of state

    SciTech Connect

    Vlasic, Thomas M.; Servio, Phillip; Rey, Alejandro D.

    2016-08-15

    This work uses density functional theory (DFT) to investigate the poorly characterized structure II gas hydrates, for various guests (empty, propane, butane, ethane-methane, propane-methane), at the atomistic scale to determine key structure and mechanical properties such as equilibrium lattice volume and bulk modulus. Several equations of state (EOS) for solids (Murnaghan, Birch-Murnaghan, Vinet, Liu) were fitted to energy-volume curves resulting from structure optimization simulations. These EOS, which can be used to characterize the compressional behaviour of gas hydrates, were evaluated in terms of their robustness. The three-parameter Vinet EOS was found to perform just as well if not better than the four-parameter Liu EOS, over the pressure range in this study. As expected, the Murnaghan EOS proved to be the least robust. Furthermore, the equilibrium lattice volumes were found to increase with guest size, with double-guest hydrates showing a larger increase than single-guest hydrates, which has significant implications for the widely used van der Waals and Platteeuw thermodynamic model for gas hydrates. Also, hydrogen bonds prove to be the most likely factor contributing to the resistance of gas hydrates to compression; bulk modulus was found to increase linearly with hydrogen bond density, resulting in a relationship that could be used predictively to determine the bulk modulus of various structure II gas hydrates. Taken together, these results fill a long existing gap in the material chemical physics of these important clathrates.

  2. Mathematical Models of Cochlear Nucleus Onset Neurons: II. Model with Dynamic Spike-Blocking State

    PubMed Central

    KALLURI, SRIDHAR; DELGUTTE, BERTRAND

    2008-01-01

    Onset (On) neurons in the cochlear nucleus (CN), characterized by their prominent response to the onset followed by little or no response to the steady-state of sustained stimuli, have a remarkable ability to entrain (firing 1 spike per cycle of a periodic stimulus) to low-frequency tones up to 1000 Hz. In this article, we present a point-neuron model with independent, excitatory auditory-nerve (AN) inputs that accounts for the ability of On neurons to both produce onset responses for high-frequency tone bursts and entrain to a wide range of low-frequency tones. With a fixed-duration spike-blocking state after a spike (an absolute refractory period), the model produces entrainment to a broad range of low-frequency tones and an On response with short interspike intervals (chopping) for high-frequency tone bursts. To produce On response patterns with no chopping, we introduce a novel, more complex, active membrane model in which the spike-blocking state is maintained until the instantaneous membrane voltage falls below a transition voltage. During the sustained depolarization for a high-frequency tone burst, the new model does not chop because it enters a spike-blocking state after the first spike and fails to leave this state until the membrane voltage returns toward rest at the end of the stimulus. The model entrains to low-frequency tones because the membrane voltage falls below the transition voltage on every cycle when the AN inputs are phase-locked. With the complex membrane model, On response patterns having moderate steady-state activity for high-frequency tone bursts (On-L) are distinguished from those having no steady-state activity (On-I) by requiring fewer AN inputs. Voltage-gated ion channels found in On-responding neurons of the CN may underlie the hypothesized dynamic spike-blocking state. These results provide a mechanistic rationale for distinguishing between the different physiological classes of CN On neurons. PMID:12435926

  3. Predictions of B{sub c} meson decay emitting pseudoscalar and heavy scalar mesons using ISGW II model

    SciTech Connect

    Sharma, Neelesh; Verma, R. C.

    2010-11-01

    Two-body hadronic weak decays of B{sub c} meson emitting pseudoscalar and heavy scalar mesons are investigated using the Spectator Quark Model. Decay amplitudes are obtained using the factorization scheme; consequently, branching ratios are predicted in the Isgur-Scora-Grinstein-Wise (ISGW II) model.

  4. A rule-based kinetic model of RNA polymerase II C-terminal domain phosphorylation

    PubMed Central

    Aitken, Stuart; Alexander, Ross D.; Beggs, Jean D.

    2013-01-01

    The complexity of many RNA processing pathways is such that a conventional systems modelling approach is inadequate to represent all the molecular species involved. We demonstrate that rule-based modelling permits a detailed model of a complex RNA signalling pathway to be defined. Phosphorylation of the RNA polymerase II (RNAPII) C-terminal domain (CTD; a flexible tail-like extension of the largest subunit) couples pre-messenger RNA capping, splicing and 3′ end maturation to transcriptional elongation and termination, and plays a central role in integrating these processes. The phosphorylation states of the serine residues of many heptapeptide repeats of the CTD alter along the coding region of genes as a function of distance from the promoter. From a mechanistic perspective, both the changes in phosphorylation and the location at which they take place on the genes are a function of the time spent by RNAPII in elongation as this interval provides the opportunity for the kinases and phosphatases to interact with the CTD. On this basis, we synthesize the available data to create a kinetic model of the action of the known kinases and phosphatases to resolve the phosphorylation pathways and their kinetics. PMID:23804443

  5. Dissecting cooperative calmodulin binding to CaM kinase II: a detailed stochastic model.

    PubMed

    Byrne, Michael J; Putkey, John A; Waxham, M Neal; Kubota, Yoshihisa

    2009-12-01

    Calmodulin (CaM) is a major Ca(2+) binding protein involved in two opposing processes of synaptic plasticity of CA1 pyramidal neurons: long-term potentiation (LTP) and depression (LTD). The N- and C-terminal lobes of CaM bind to its target separately but cooperatively and introduce complex dynamics that cannot be well understood by experimental measurement. Using a detailed stochastic model constructed upon experimental data, we have studied the interaction between CaM and Ca(2+)-CaM-dependent protein kinase II (CaMKII), a key enzyme underlying LTP. The model suggests that the accelerated binding of one lobe of CaM to CaMKII, when the opposing lobe is already bound to CaMKII, is a critical determinant of the cooperative interaction between Ca(2+), CaM, and CaMKII. The model indicates that the target-bound Ca(2+) free N-lobe has an extended lifetime and may regulate the Ca(2+) response of CaMKII during LTP induction. The model also reveals multiple kinetic pathways which have not been previously predicted for CaM-dissociation from CaMKII.

  6. Survey of non-linear hydrodynamic models of type-II Cepheids

    NASA Astrophysics Data System (ADS)

    Smolec, R.

    2016-03-01

    We present a grid of non-linear convective type-II Cepheid models. The dense model grids are computed for 0.6 M⊙ and a range of metallicities ([Fe/H] = -2.0, -1.5, -1.0), and for 0.8 M⊙ ([Fe/H] = -1.5). Two sets of convective parameters are considered. The models cover the full temperature extent of the classical instability strip, but are limited in luminosity; for the most luminous models, violent pulsation leads to the decoupling of the outermost model shell. Hence, our survey reaches only the shortest period RV Tau domain. In the Hertzsprung-Russell diagram, we detect two domains in which period-doubled pulsation is possible. The first extends through the BL Her domain and low-luminosity W Vir domain (pulsation periods ˜2-6.5 d). The second domain extends at higher luminosities (W Vir domain; periods >9.5 d). Some models within these domains display period-4 pulsation. We also detect very narrow domains (˜10 K wide) in which modulation of pulsation is possible. Another interesting phenomenon we detect is double-mode pulsation in the fundamental mode and in the fourth radial overtone. Fourth overtone is a surface mode, trapped in the outer model layers. Single-mode pulsation in the fourth overtone is also possible on the hot side of the classical instability strip. The origin of the above phenomena is discussed. In particular, the role of resonances in driving different pulsation dynamics as well as in shaping the morphology of the radius variation curves is analysed.

  7. Evaluation of the aerosol vertical distribution in global aerosol models through comparison against CALIOP measurements: AeroCom phase II results: AEROSOL PROFILES IN AEROCOM II GCM

    SciTech Connect

    Koffi, Brigitte; Schulz, Michael; Bréon, François-Marie; Dentener, Frank; Steensen, Birthe Marie; Griesfeller, Jan; Winker, David; Bauer, Susanne E.; Bellouin, Nicolas; Berntsen, Terje; Bian, Huisheng; Chin, Mian; Diehl, Thomas; Easter, Richard; Ghan, Steven; Hauglustaine, Didier A.; Iversen, Trond; Kirkevåg, Alf; Liu, Xiaohong; Lohmann, Ulrike; Myhre, Gunnar; Rasch, Phil; Seland, Øyvind; Skeie, Ragnhild B.; Steenrod, Stephen D.; Stier, Philip; Tackett, Jason; Takemura, Toshihiko; Tsigaridis, Kostas; Vuolo, Maria Raffaella; Yoon, Jinho; Zhang, Kai

    2016-06-27

    The ability of eleven models in simulating the aerosol vertical distribution from regional to global scales, as part of the second phase of the AeroCom model inter-comparison initiative (AeroCom II) is assessed and compared to results of the first phase. The evaluation is performed using a global monthly gridded dataset of aerosol extinction profiles built on purpose from the CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) Layer Product 3.01. Results over 12 sub-continental regions show that five models improved whereas three degraded in reproducing the Zα 0-6 km mean extinction height diagnostic, which is computed over the 0-6 km altitude range for each studied region and season. While the models’ performance remains highly variable, it has generally improved in terms of inter-regional diversity and seasonality. The biases in Zα 0-6 km have notably decreased in the U.S. and European industrial and downwind maritime regions, whereas the timing of the Zα 0-6 km peak season has improved for all but two models. However, most of the models now show a Zα 0-6 km underestimation over land, notably in the dust and biomass burning regions in Asia and Africa. At global scale, the AeroCom II models better reproduce the Zα 0-6 km latitudinal variability over ocean than over land. Hypotheses for the (changes in the) the performance of the individual models and for the inter-model diversity are discussed. We also provide an analysis of the CALIOP limitations and uncertainties that can contribute to the differences between the simulations and observations.

  8. High resolution meteorological modelling of the Inntal valley atmosphere, Part II: applications to dispersion modelling

    NASA Astrophysics Data System (ADS)

    Arnold, D.; Schicker, I.; Seibert, P.

    2009-09-01

    Orography and local meteorology play a major role in Alpine valleys, as they are linked with valley and slope wind systems, stagnation and recirculation, temperature inversions and turbulence. Thus, they have a strong influence of transport and dilution of pollutants in the valley, affecting human health, and sound propagation. Shallow stable layers at the valley floor and low wind speed conditions, especially in autumn and winter, trap pollutants and thus cause unfavourable dispersion conditions , possibly leading to exceedances of air pollution limits. Moreover, under certain synoptic conditions such as persistent high-pressure systems inversion conditions prevail for days. Emissions may accumulate in the valley from day to day and thus critical levels of pollutants may be reached. With the current computer capabilities, numerical meteorological models and particle dispersion models are powerful tools to investigate such situations and their impact on emission-side measures. Output from the limited area meteorological model MM5 for selected synoptic periods of special interest regarding air quality conditions (see contribution by Schicker et al., this session) will be used as input to the Lagrangian particle dispersion model FLEXPARTv6.2. Currently two specific versions of FLEXPART exist to work in the meso and local scale, WRF-FLEXPARTv6.2 and MM5v3-7.FLEXPARTv6.2, which use WRF and MM5 fields as meteorological input, respectively. Extensive tests will be performed with the MM5-driven version and additional preliminary ones with the WRF version. Dispersion calculations for CO and NOx will be performed in a receptor-oriented approach for three stations and with different meteorological input resolutions. The target stations will be Innsbruck, located at the bottom of the Inn valley, and Nordkette, located on the northern slopes of the valley. Source-receptor sensitivities (SRS) will be obtained to see the major sources which contribute to the measurements for

  9. Deriving remote sensing reflectance from turbid Case II waters using green-shortwave infrared bands based model

    NASA Astrophysics Data System (ADS)

    Chen, Jun; Yin, Shoujing; Xiao, Rulin; Xu, Qianxiang; Lin, Changsong

    2014-04-01

    The objectives of this study are to validate the applicability of a shortwave infrared atmospheric correction model (SWIR-based model) in deriving remote sensing reflectance in turbid Case II waters, and to improve that model using a proposed green-shortwave infrared model (GSWIR-based model). In a GSWIR-based model, the aerosol type is determined by a SWIR-based model and the reflectance due to aerosol scattering is calculated using spectral slope technology. In this study, field measurements collected from three independent cruises from two different Case II waters were used to compare models. The results indicate that both SWIR- and GSWIR-based models can be used to derive the remote sensing reflectance at visible wavelengths in turbid Case II waters, but GSWIR-based models are superior to SWIR-based models. Using the GSWIR-based model decreases uncertainty in remote sensing reflectance retrievals in turbid Case II waters by 2.6-12.1%. In addition, GSWIR-based model’s sensitivity to user-supplied parameters was determined using the numerical method, which indicated that the GSWIR-based model is more sensitive to the uncertainty of spectral slope technology than to that of aerosol type retrieval methodology. Due to much lower noise tolerance of GSWIR-based model in the blue and near-infrared regions, the GSWIR-based model performs poorly in determining remote sensing reflectance at these wavelengths, which is consistent with the GSWIR-based model’s accuracy evaluation results.

  10. Dynamics of stochastic predator-prey models with Holling II functional response

    NASA Astrophysics Data System (ADS)

    Liu, Qun; Zu, Li; Jiang, Daqing

    2016-08-01

    In this paper, we consider the dynamics of stochastic predator-prey models with Holling II functional response. For the stochastic systems, we firstly establish sufficient conditions for the existence of the globally positive solutions. Then we investigate the asymptotic moment estimations of the positive solutions and study the ultimately bounded in the mean of them. Thirdly, by constructing some suitable Lyapunov functions, we verify that there are unique stationary distributions and they are ergodic. The obtained results show that the systems still retain some stability in the sense of weak stability provided that the intensity of the white noise is relatively small. Finally, some numerical simulations are introduced to illustrate our main results.

  11. Phase II monitoring of auto-correlated linear profiles using linear mixed model

    NASA Astrophysics Data System (ADS)

    Narvand, A.; Soleimani, P.; Raissi, Sadigh

    2013-05-01

    In many circumstances, the quality of a process or product is best characterized by a given mathematical function between a response variable and one or more explanatory variables that is typically referred to as profile. There are some investigations to monitor auto-correlated linear and nonlinear profiles in recent years. In the present paper, we use the linear mixed models to account autocorrelation within observations which is gathered on phase II of the monitoring process. We undertake that the structure of correlated linear profiles simultaneously has both random and fixed effects. The work enhanced a Hotelling's T 2 statistic, a multivariate exponential weighted moving average (MEWMA), and a multivariate cumulative sum (MCUSUM) control charts to monitor process. We also compared their performances, in terms of average run length criterion, and designated that the proposed control charts schemes could effectively act in detecting shifts in process parameters. Finally, the results are applied on a real case study in an agricultural field.

  12. Toward a Network Model of MHC Class II-Restricted Antigen Processing

    PubMed Central

    Miller, Michael A.; Ganesan, Asha Purnima V.; Eisenlohr, Laurence C.

    2013-01-01

    The standard model of Major Histocompatibility Complex class II (MHCII)-restricted antigen processing depicts a straightforward, linear pathway: internalized antigens are converted into peptides that load in a chaperone dependent manner onto nascent MHCII in the late endosome, the complexes subsequently trafficking to the cell surface for recognition by CD4+ T cells (TCD4+). Several variations on this theme, both moderate and radical, have come to light but these alternatives have remained peripheral, the conventional pathway generally presumed to be the primary driver of TCD4+ responses. Here we continue to press for the conceptual repositioning of these alternatives toward the center while proposing that MHCII processing be thought of less in terms of discrete pathways and more in terms of a network whose major and minor conduits are variable depending upon many factors, including the epitope, the nature of the antigen, the source of the antigen, and the identity of the antigen-presenting cell. PMID:24379819

  13. Thermohaline Circulation Stability: A Box Model Study. Part II: Coupled Atmosphere-Ocean Model.

    NASA Astrophysics Data System (ADS)

    Lucarini, Valerio; Stone, Peter H.

    2005-02-01

    A thorough analysis of the stability of a coupled version of an interhemispheric three-box model of thermohaline circulation (THC) is presented. This study follows a similarly structured analysis of an uncoupled version of the same model presented in Part I of this paper. The model consists of a northern high-latitude box, a tropical box, and a southern high-latitude box, which can be thought of as corresponding to the northern, tropical, and southern Atlantic Ocean, respectively. This paper examines how the strength of THC changes when the system undergoes forcings representing global warming conditions.Since a coupled model is used, a direct representation of the radiative forcing is possible because the main atmospheric physical processes responsible for freshwater and heat fluxes are formulated separately. Each perturbation to the initial equilibrium is characterized by the total radiative forcing realized, by the rate of increase, and by the north-south asymmetry. Although only weakly asymmetric or symmetric radiative forcings are representative of physically reasonable conditions, general asymmetric forcings are considered in order to get a more complete picture of the mathematical properties of the system. The choice of suitably defined metrics makes it possible to determine the boundary dividing the set of radiative forcing scenarios that lead the system to equilibria characterized by a THC pattern similar to the present one, from those that drive the system to equilibria where the THC is reversed. This paper also considers different choices for the atmospheric transport parameterizations and for the ratio between the high-latitude and tropical radiative forcing. It is generally found that fast forcings are more effective than slow forcings in disrupting the present THC pattern, forcings that are stronger in the northern box are also more effective in destabilizing the system, and very slow forcings do not destabilize the system whatever their asymmetry

  14. High particulate iron(II) content in glacially sourced dusts enhances productivity of a model diatom

    PubMed Central

    Shoenfelt, Elizabeth M.; Sun, Jing; Winckler, Gisela; Kaplan, Michael R.; Borunda, Alejandra L.; Farrell, Kayla R.; Moreno, Patricio I.; Gaiero, Diego M.; Recasens, Cristina; Sambrotto, Raymond N.; Bostick, Benjamin C.

    2017-01-01

    Little is known about the bioavailability of iron (Fe) in natural dusts and the impact of dust mineralogy on Fe utilization by photosynthetic organisms. Variation in the supply of bioavailable Fe to the ocean has the potential to influence the global carbon cycle by modulating primary production in the Southern Ocean. Much of the dust deposited across the Southern Ocean is sourced from South America, particularly Patagonia, where the waxing and waning of past and present glaciers generate fresh glaciogenic material that contrasts with aged and chemically weathered nonglaciogenic sediments. We show that these two potential sources of modern-day dust are mineralogically distinct, where glaciogenic dust sources contain mostly Fe(II)-rich primary silicate minerals, and nearby nonglaciogenic dust sources contain mostly Fe(III)-rich oxyhydroxide and Fe(III) silicate weathering products. In laboratory culture experiments, Phaeodactylum tricornutum, a well-studied coastal model diatom, grows more rapidly, and with higher photosynthetic efficiency, with input of glaciogenic particulates compared to that of nonglaciogenic particulates due to these differences in Fe mineralogy. Monod nutrient accessibility models fit to our data suggest that particulate Fe(II) content, rather than abiotic solubility, controls the Fe bioavailability in our Fe fertilization experiments. Thus, it is possible for this diatom to access particulate Fe in dusts by another mechanism besides uptake of unchelated Fe (Fe′) dissolved from particles into the bulk solution. If this capability is widespread in the Southern Ocean, then dusts deposited to the Southern Ocean in cold glacial periods are likely more bioavailable than those deposited in warm interglacial periods. PMID:28691098

  15. Modelling reverberation mapping data - II. Dynamical modelling of the Lick AGN Monitoring Project 2008 data set

    NASA Astrophysics Data System (ADS)

    Pancoast, Anna; Brewer, Brendon J.; Treu, Tommaso; Park, Daeseong; Barth, Aaron J.; Bentz, Misty C.; Woo, Jong-Hak

    2014-12-01

    We present dynamical modelling of the broad-line region (BLR) for a sample of five Seyfert 1 galaxies using reverberation mapping data taken by the Lick AGN Monitoring Project in 2008. By modelling the AGN continuum light curve and Hβ line profiles directly, we are able to constrain the geometry and kinematics of the BLR and make a measurement of the black hole mass that does not depend upon the virial factor, f, needed in traditional reverberation mapping analysis. We find that the geometry of the BLR is generally a thick disc viewed close to face-on. While the Hβ emission is found to come preferentially from the far side of the BLR, the mean size of the BLR is consistent with the lags measured with cross-correlation analysis. The BLR kinematics are found to be consistent with either inflowing motions or elliptical orbits, often with some combination of the two. We measure black hole masses of log _{10}(M_ BH/M_{odot })=6.62^{+0.10}_{-0.13} for Arp 151, 7.42^{+0.26}_{-0.27} for Mrk 1310, 7.59^{+0.24}_{-0.21} for NGC 5548, 6.37^{+0.21}_{-0.16} for NGC 6814, and 6.99^{+0.32}_{-0.25} for SBS 1116+583A. The f factors measured individually for each AGN are found to correlate with inclination angle, although not with M BH, L5100, or FWHM/σ of the emission line profile.

  16. Ries crater and suevite revisited—Observations and modeling Part II: Modeling

    NASA Astrophysics Data System (ADS)

    Artemieva, N. A.; Wünnemann, K.; Krien, F.; Reimold, W. U.; Stöffler, D.

    2013-04-01

    We present the results of numerical modeling of the formation of the Ries crater utilizing the two hydrocodes SOVA and iSALE. These standard models allow us to reproduce crater shape, size, and morphology, and composition and extension of the continuous ejecta blanket. Some of these results cannot, however, be readily reconciled with observations: the impact plume above the crater consists mainly of molten and vaporized sedimentary rocks, containing very little material in comparison with the ejecta curtain; at the end of the modification stage, the crater floor is covered by a thick layer of impact melt with a total volume of 6-11 km3; the thickness of true fallback material from the plume inside the crater does not exceed a couple of meters; ejecta from all stratigraphic units of the target are transported ballistically; no separation of sedimentary and crystalline rocks—as observed between suevites and Bunte Breccia at Ries—is noted. We also present numerical results quantifying the existing geological hypotheses of Ries ejecta emplacement from an impact plume, by melt flow, or by a pyroclastic density current. The results show that none of these mechanisms is consistent with physical constraints and/or observations. Finally, we suggest a new hypothesis of suevite formation and emplacement by postimpact interaction of hot impact melt with water or volatile-rich sedimentary rocks.

  17. Polarized Light Scanning Cryomacroscopy, Part II: Thermal Modeling and Analysis of Experimental Observations

    PubMed Central

    Feig, Justin S.G.; Solanki, Prem K.; Eisenberg, David P.; Rabin, Yoed

    2016-01-01

    This study aims at developing thermal analysis tools and explaining experimental observations made by means of polarized-light cryomacroscopy (Part I). Thermal modeling is based on finite elements analysis (FEA), where two model parameters are extracted from thermal measurements: (i) the overall heat transfer coefficient between the cuvette and the cooling chamber, and (ii) the effective thermal conductivity within the cryoprotective agent (CPA) at the upper part of the cryogenic temperature range. The effective thermal conductivity takes into account enhanced heat transfer due to convection currents within the CPA, creating the so-called Bénard cells. Comparison of experimental results with simulation data indicates that the uncertainty in simulations due to the propagation of uncertainty in measured physical properties exceeds the uncertainty in experimental measurements, which validates the modeling approach. It is shown in this study that while a cavity may form in the upper-center portion of the vitrified CPA, it has very little effect on estimating the temperature distribution within the domain. This cavity is driven by thermal contraction of the CPA, with the upper-center of the domain transitioning to glass last. Finally, it is demonstrated in this study that additional stresses may develop within the glass transition temperature range due to nonlinear behavior of the thermal expansion coefficient. This effect is reported here for the first time in the context of cryobiology, using the capabilities of polarized-light cryomacroscopy. PMID:27343139

  18. Polarized light scanning cryomacroscopy, part II: Thermal modeling and analysis of experimental observations.

    PubMed

    Feig, Justin S G; Solanki, Prem K; Eisenberg, David P; Rabin, Yoed

    2016-10-01

    This study aims at developing thermal analysis tools and explaining experimental observations made by means of polarized-light cryomacroscopy (Part I). Thermal modeling is based on finite elements analysis (FEA), where two model parameters are extracted from thermal measurements: (i) the overall heat transfer coefficient between the cuvette and the cooling chamber, and (ii) the effective thermal conductivity within the cryoprotective agent (CPA) at the upper part of the cryogenic temperature range. The effective thermal conductivity takes into account enhanced heat transfer due to convection currents within the CPA, creating the so-called Bénard cells. Comparison of experimental results with simulation data indicates that the uncertainty in simulations due to the propagation of uncertainty in measured physical properties exceeds the uncertainty in experimental measurements, which validates the modeling approach. It is shown in this study that while a cavity may form in the upper-center portion of the vitrified CPA, it has very little effect on estimating the temperature distribution within the domain. This cavity is driven by thermal contraction of the CPA, with the upper-center of the domain transitioning to glass last. Finally, it is demonstrated in this study that additional stresses may develop within the glass transition temperature range due to nonlinear behavior of the thermal expansion coefficient. This effect is reported here for the first time in the context of cryobiology, using the capabilities of polarized-light cryomacroscopy. Copyright © 2016. Published by Elsevier Inc.

  19. FutureTox II: In vitro Data and In Silico Models for Predictive Toxicology

    PubMed Central

    Knudsen, Thomas B.; Keller, Douglas A.; Sander, Miriam; Carney, Edward W.; Doerrer, Nancy G.; Eaton, David L.; Fitzpatrick, Suzanne Compton; Hastings, Kenneth L.; Mendrick, Donna L.; Tice, Raymond R.; Watkins, Paul B.; Whelan, Maurice

    2015-01-01

    FutureTox II, a Society of Toxicology Contemporary Concepts in Toxicology workshop, was held in January, 2014. The meeting goals were to review and discuss the state of the science in toxicology in the context of implementing the NRC 21st century vision of predicting in vivo responses from in vitro and in silico data, and to define the goals for the future. Presentations and discussions were held on priority concerns such as predicting and modeling of metabolism, cell growth and differentiation, effects on sensitive subpopulations, and integrating data into risk assessment. Emerging trends in technologies such as stem cell-derived human cells, 3D organotypic culture models, mathematical modeling of cellular processes and morphogenesis, adverse outcome pathway development, and high-content imaging of in vivo systems were discussed. Although advances in moving towards an in vitro/in silico based risk assessment paradigm were apparent, knowledge gaps in these areas and limitations of technologies were identified. Specific recommendations were made for future directions and research needs in the areas of hepatotoxicity, cancer prediction, developmental toxicity, and regulatory toxicology. PMID:25628403

  20. Viscoelastic Model for Lung Parenchyma for Multi-Scale Modeling of Respiratory System, Phase II: Dodecahedral Micro-Model

    SciTech Connect

    Freed, Alan D.; Einstein, Daniel R.; Carson, James P.; Jacob, Rick E.

    2012-03-01

    In the first year of this contractual effort a hypo-elastic constitutive model was developed and shown to have great potential in modeling the elastic response of parenchyma. This model resides at the macroscopic level of the continuum. In this, the second year of our support, an isotropic dodecahedron is employed as an alveolar model. This is a microscopic model for parenchyma. A hopeful outcome is that the linkage between these two scales of modeling will be a source of insight and inspiration that will aid us in the final year's activity: creating a viscoelastic model for parenchyma.

  1. Bayesian hierarchical modeling of patient subpopulations: Efficient designs of Phase II oncology clinical trials

    PubMed Central

    Berry, Scott M; Broglio, Kristine R; Groshen, Susan; Berry, Donald A

    2015-01-01

    Background In oncology, the treatment paradigm is shifting toward personalized medicine, where the goal is to match patients to the treatments most likely to deliver benefit. Treatment effects in various subpopulations may provide some information about treatment effects in other subpopulations. Purpose We compare different approaches to Phase II trial design where a new treatment is being investigated in several groups of patients. We compare considering each group in an independent trial to a single trial with hierarchical modeling of the patient groups. Methods We assume four patient groups with different background response rates and simulate operating characteristics of three trial designs, Simon’s Optimal Two-Stage design, a Bayesian adaptive design with frequent interim analyses, and a Bayesian adaptive design with frequent interim analyses and hierarchical modeling across patient groups. Results Simon’s designs are based on 10% Type I and Type II error rates. The independent Bayesian designs are tuned to have similar error rates, but may have a slightly smaller mean sample size due to more frequent interim analyses. Under the null, the mean sample size is 2–4 patients smaller. A hierarchical model across patient groups can provide additional power and a further reduction in mean sample size. Under the null, the addition of the hierarchical model decreases the mean sample size an additional 4–7 patients in each group. Under the alternative hypothesis, power is increased to at least 98% in all groups. Limitations Hierarchical borrowing can make finding a single group in which the treatment is promising, if there is only one, more difficult. In a scenario where the treatment is uninteresting in all but one group, power for that one group is reduced to 65%. When the drug appears promising in some groups and not in others, there is potential for borrowing to inflate the Type I error rate. Conclusions The Bayesian hierarchical design is more likely to

  2. A valence bond model for aqueous Cu(II) and Zn(II) ions in the AMOEBA polarizable force field.

    PubMed

    Xiang, Jin Yu; Ponder, Jay W

    2013-04-05

    A general molecular mechanics (MM) model for treating aqueous Cu(2+) and Zn(2+) ions was developed based on valence bond (VB) theory and incorporated into the atomic multipole optimized energetics for biomolecular applications (AMOEBA) polarizable force field. Parameters were obtained by fitting MM energies to that computed by ab initio methods for gas-phase tetra- and hexa-aqua metal complexes. Molecular dynamics (MD) simulations using the proposed AMOEBA-VB model were performed for each transition metal ion in aqueous solution, and solvent coordination was evaluated. Results show that the AMOEBA-VB model generates the correct square-planar geometry for gas-phase tetra-aqua Cu(2+) complex and improves the accuracy of MM model energetics for a number of ligation geometries when compared to quantum mechanical (QM) computations. On the other hand, both AMOEBA and AMOEBA-VB generate results for Zn(2+)-water complexes in good agreement with QM calculations. Analyses of the MD trajectories revealed a six-coordination first solvation shell for both Cu(2+) and Zn(2+) ions in aqueous solution, with ligation geometries falling in the range reported by previous studies. Copyright © 2012 Wiley Periodicals, Inc.

  3. A Novel Mouse Model of a Patient Mucolipidosis II Mutation Recapitulates Disease Pathology*

    PubMed Central

    Paton, Leigh; Bitoun, Emmanuelle; Kenyon, Janet; Priestman, David A.; Oliver, Peter L.; Edwards, Benjamin; Platt, Frances M.; Davies, Kay E.

    2014-01-01

    Mucolipidosis II (MLII) is a lysosomal storage disorder caused by loss of N-acetylglucosamine-1-phosphotransferase, which tags lysosomal enzymes with a mannose 6-phosphate marker for transport to the lysosome. In MLII, the loss of this marker leads to deficiency of multiple enzymes and non-enzymatic proteins in the lysosome, leading to the storage of multiple substrates. Here we present a novel mouse model of MLII homozygous for a patient mutation in the GNPTAB gene. Whereas the current gene knock-out mouse model of MLII lacks some of the characteristic features of the human disease, our novel mouse model more fully recapitulates the human pathology, showing growth retardation, skeletal and facial abnormalities, increased circulating lysosomal enzymatic activities, intracellular lysosomal storage, and reduced life span. Importantly, MLII behavioral deficits are characterized for the first time, including impaired motor function and psychomotor retardation. Histological analysis of the brain revealed progressive neurodegeneration in the cerebellum with severe Purkinje cell loss as the underlying cause of the ataxic gait. In addition, based on the loss of Npc2 (Niemann-Pick type C 2) protein expression in the brain, the mice were treated with 2-hydroxypropyl-β-cyclodextrin, a drug previously reported to rescue Purkinje cell death in a mouse model of Niemann-Pick type C disease. No improvement in brain pathology was observed. This indicates that cerebellar degeneration is not primarily triggered by loss of Npc2 function. This study emphasizes the value of modeling MLII patient mutations to generate clinically relevant mouse mutants to elucidate the pathogenic molecular pathways of MLII and address their amenability to therapy. PMID:25107912

  4. Identification of age-dependent motor and neuropsychological behavioural abnormalities in a mouse model of Mucopolysaccharidosis Type II

    PubMed Central

    Gleitz, Hélène F. E.; O’Leary, Claire; Holley, Rebecca J.

    2017-01-01

    Severe mucopolysaccharidosis type II (MPS II) is a progressive lysosomal storage disease caused by mutations in the IDS gene, leading to a deficiency in the iduronate-2-sulfatase enzyme that is involved in heparan sulphate and dermatan sulphate catabolism. In constitutive form, MPS II is a multi-system disease characterised by progressive neurocognitive decline, severe skeletal abnormalities and hepatosplenomegaly. Although enzyme replacement therapy has been approved for treatment of peripheral organs, no therapy effectively treats the cognitive symptoms of the disease and novel therapies are in development to remediate this. Therapeutic efficacy and subsequent validation can be assessed using a variety of outcome measures that are translatable to clinical practice, such as behavioural measures. We sought to consolidate current knowledge of the cognitive, skeletal and motor abnormalities present in the MPS II mouse model by performing time course behavioural examinations of working memory, anxiety, activity levels, sociability and coordination and balance, up to 8 months of age. Cognitive decline associated with alterations in spatial working memory is detectable at 8 months of age in MPS II mice using spontaneous alternation, together with an altered response to novel environments and anxiolytic behaviour in the open-field. Coordination and balance on the accelerating rotarod were also significantly worse at 8 months, and may be associated with skeletal changes seen in MPS II mice. We demonstrate that the progressive nature of MPS II disease is also seen in the mouse model, and that cognitive and motor differences are detectable at 8 months of age using spontaneous alternation, the accelerating rotarod and the open-field tests. This study establishes neurological, motor and skeletal measures for use in pre-clinical studies to develop therapeutic approaches in MPS II. PMID:28207863

  5. Towards multi-resolution global climate modeling with ECHAM6-FESOM. Part II: climate variability

    NASA Astrophysics Data System (ADS)

    Rackow, T.; Goessling, H. F.; Jung, T.; Sidorenko, D.; Semmler, T.; Barbi, D.; Handorf, D.

    2016-06-01

    This study forms part II of two papers describing ECHAM6-FESOM, a newly established global climate model with a unique multi-resolution sea ice-ocean component. While part I deals with the model description and the mean climate state, here we examine the internal climate variability of the model under constant present-day (1990) conditions. We (1) assess the internal variations in the model in terms of objective variability performance indices, (2) analyze variations in global mean surface temperature and put them in context to variations in the observed record, with particular emphasis on the recent warming slowdown, (3) analyze and validate the most common atmospheric and oceanic variability patterns, (4) diagnose the potential predictability of various climate indices, and (5) put the multi-resolution approach to the test by comparing two setups that differ only in oceanic resolution in the equatorial belt, where one ocean mesh keeps the coarse ~1° resolution applied in the adjacent open-ocean regions and the other mesh is gradually refined to ~0.25°. Objective variability performance indices show that, in the considered setups, ECHAM6-FESOM performs overall favourably compared to five well-established climate models. Internal variations of the global mean surface temperature in the model are consistent with observed fluctuations and suggest that the recent warming slowdown can be explained as a once-in-one-hundred-years event caused by internal climate variability; periods of strong cooling in the model (`hiatus' analogs) are mainly associated with ENSO-related variability and to a lesser degree also to PDO shifts, with the AMO playing a minor role. Common atmospheric and oceanic variability patterns are simulated largely consistent with their real counterparts. Typical deficits also found in other models at similar resolutions remain, in particular too weak non-seasonal variability of SSTs over large parts of the ocean and episodic periods of almost absent

  6. ANG II-induced hypertension in the VCD mouse model of menopause is prevented by estrogen replacement during perimenopause.

    PubMed

    Pollow, Dennis P; Romero-Aleshire, Melissa J; Sanchez, Jessica N; Konhilas, John P; Brooks, Heddwen L

    2015-12-15

    Premenopausal females are resistant to the development of hypertension, and this protection is lost after the onset of menopause, resulting in a sharp increase in disease onset and severity. However, it is unknown how a fluctuating ovarian hormone environment during the transition from perimenopause to menopause impacts the onset of hypertension, and whether interventions during perimenopause prevent disease onset after menopause. A gradual transition to menopause was induced by repeated daily injections of 4-vinylcyclohexene diepoxide (VCD). ANG II (800 ng·kg(-1)·min(-1)) was infused into perimenopausal and menopausal female mice for 14 days. A separate cohort of mice received 17β-estradiol replacement during perimenopause. ANG II infusion produced significantly higher mean arterial pressure (MAP) in menopausal vs. cycling females, and 17β-estradiol replacement prevented this increase. In contrast, MAP was not significantly different when ANG II was infused into perimenopausal and cycling females, suggesting that female resistance to ANG II-induced hypertension is intact during perimenopause. ANG II infusion caused a significant glomerular hypertrophy, and hypertrophy was not impacted by hormonal status. Expression levels of aquaporin-2 (AQP2), a collecting duct protein, have been suggested to reflect blood pressure. AQP2 protein expression was significantly downregulated in the renal cortex of the ANG II-infused menopause group, where blood pressure was increased. AQP2 expression levels were restored to control levels with 17β-estradiol replacement. This study indicates that the changing hormonal environment in the VCD model of menopause impacts the severity of ANG II-induced hypertension. These data highlight the utility of the ovary-intact VCD model of menopause as a clinically relevant model to investigate the physiological mechanisms of hypertension that occur in women during the transition into menopause.

  7. Sparse geologic dictionaries for subsurface flow model calibration: Part II. Robustness to uncertainty

    NASA Astrophysics Data System (ADS)

    Khaninezhad, Mohammadreza Mohammad; Jafarpour, Behnam; Li, Lianlin

    2012-04-01

    We introduced sparse geologic dictionaries for formulating and solving subsurface flow model calibration problems in Part I. A key assumption was the availability of a reliable prior model library for construction of a relevant sparse geologic dictionary that was used to constrain the inversion solution. In practice, however, the spatial connectivity in rock physical property distributions has to be inferred from uncertain and incomplete sources of information, including qualitative geologic interpretations, formation type and outcrop maps, as well as scattered measurements (e.g., well core, log data, and seismic maps). Thus, the geologic continuity model that is used for generating prior models is likely to carry significant uncertainty. In Part II, we investigate the performance of the proposed method under uncertain and incorrect prior continuity models. We show that, unlike the conventional reduced-order parameterization methods such as truncated SVD, diverse geologic dictionaries are robust against uncertainty in the structural prior model. This robustness is attributed to the selection property of the sparse reconstruction algorithm and the connectivity exhibited by the dictionary elements. Under highly uncertain prior models, the reconstruction problem is reduced to identifying and combining relevant elements from a large and diverse geologic dictionary. Diversity of the dictionary further enhances solution sparsity since a large number of dictionary elements will have negligible contribution to the solution. Consequently, the inversion provides considerable flexibility to accommodate significant levels of variability (uncertainty) in prior geologic models. As an extreme case, we also evaluate the performance of the proposed method when even the formation type (e.g., Gaussian versus non-Gaussian) is uncertain. In addition, we examine the sensitivity of the proposed method to noise in the flow data, where we observe solution underestimation effects due to l1

  8. Dysfunctional Transforming Growth Factor-β Receptor II Accelerates Prostate Tumorigenesis in the TRAMP Mouse Model

    PubMed Central

    Pu, Hong; Collazo, Joanne; Jones, Elisabeth; Gayheart, Dustin; Sakamoto, Shinichi; Vogt, Adam; Mitchell, Bonnie; Kyprianou, Natasha

    2009-01-01

    The contribution of a dysfunctional TGF-β type II receptor (TGFβRII) to prostate cancer initiation and progression was investigated in an in vivo mouse model. Transgenic mice harboring the dominant-negative mutant TGF-β type II receptor (DNTGFβRII) in mouse epithelial cell were crossed with the TRAMP prostate cancer transgenic mouse to characterize the in vivo consequences of inactivated TGF-β signaling on prostate tumor initiation and progression. Histopathological diagnosis of prostate specimens from the TRAMP+/DNTGFβRII double transgenic mice, revealed the appearance of early malignant changes and subsequently highly aggressive prostate tumors at a younger age, compared to littermates TRAMP+/Wt TGFβRII mice. Immunohistochemical and western blotting analysis revealed significantly increased proliferative and apoptotic activities, as well as vascularity and macrophage infiltration that correlated with an elevated VEGF and MCP-1 protein levels in prostates from TRAMP+/DNTGFβRII+ mice. An epithelial-mesenchymal transition (EMT)-effect was also detected in prostates of TRAMP+/DNTGFβRII mice, as documented by the loss of epithelial markers (E-cadherin and β-catenin) and upregulation of mesenchymal markers (N-cadherin) and EMT-transcription factor Snail. A significant increase in the androgen receptor (AR) mRNA and protein levels was associated with the early onset of prostate tumorigenesis in TRAMP+/DNTGFβRII mice. Our results indicate that in vivo disruption of TGF-β signaling accelerates the pathological malignant changes in the prostate by altering the kinetics of prostate growth and inducing EMT. The study also suggests that a dysfunctional TGFβRII augments AR expression and promotes inflammation in early stage tumor growth thus conferring a significant contribution by TGF-β to prostate cancer progression. PMID:19738062

  9. Evaluation of type II thyroplasty on phonatory physiology in an excised canine larynx model.

    PubMed

    Devine, Erin E; Hoffman, Matthew R; McCulloch, Timothy M; Jiang, Jack J

    2017-02-01

    Type II thyroplasty is an alternative treatment for spasmodic dysphonia, addressing hyperadduction by incising and lateralizing the thyroid cartilage. We quantified the effect of lateralization width on phonatory physiology using excised canine larynges. Normal closure, hyperadduction, and type II thyroplasty (lateralized up to 5 mm at 1-mm increments with hyperadducted arytenoids) were simulated in excised larynges (N = 7). Aerodynamic, acoustic, and videokymographic data were recorded at three subglottal pressures relative to phonation threshold pressure (PTP). One-way repeated measures analysis of variance assessed effect of condition on aerodynamic parameters. Random intercepts linear mixed effects models assessed effects of condition and subglottal pressure on acoustic and videokymographic parameters. PTP differed across conditions (P < .001). Condition affected percent shimmer (P < .005) but not percent jitter. Both pressure (P < .03) and condition (P < .001) affected fundamental frequency. Pressure affected vibratory amplitude (P < .05) and intrafold phase difference (P < .05). Condition affected phase difference between the vocal folds (P < .001). Hyperadduction increased PTP and worsened perturbation compared to normal, with near normal physiology restored with 1-mm lateralization. Further lateralization deteriorated voice quality and increased PTP. Acoustic and videokymographic results indicate that normal physiologic relationships between subglottal pressure and vibration are preserved at optimal lateralization width, but then degrade with further lateralization. The 1-mm optimal width observed here is due to the small canine larynx size. Future human trials would likely demonstrate a greater optimal width, with patient-specific value potentially determined based on larynx size and symptom severity. NA Laryngoscope, 2016 127:396-404, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  10. Icosahedral quasicrystal decoration models. II. Optimization under realistic Al-Mn potentials

    SciTech Connect

    Mihalkovic, M. |; Zhu, W.; Henley, C.L.; Phillips, R.

    1996-04-01

    We have constructed and relaxed over 200 different finite structure models for the quasicrystal {ital i}-AlMn based on decorations of the {open_quote}{open_quote}canonical-cell tiling.{close_quote}{close_quote} We adopted {ital ab} {ital initio}-based pair potentials with strong Friedel oscillations, which reproduce the phase diagram of real Al-Mn intermetallic crystal structures fairly well. Our various decoration rules encompass cases with face-centered icosahedral (FCI) symmetry and with simple icosahedral (SI) symmetry, and include additional variations in the occupancy and/or chemistry of certain site types. Each decoration was applied to 11 distinct periodic approximants of the tiling. We found that (i) the relaxed atomic positions of each site type can be closely approximated by fixed positions on each tile type, even though the environments (beyond the first neighbor) are inequivalent. (ii) Models with simple icosahedral (SI) space-group symmetry were better than those with face-centered icosahedral (FCI) space-group symmetry. (iii) {open_quote}{open_quote}Loose{close_quote}{close_quote} decorations, containing voids almost large enough for an atom, were better than the {open_quote}{open_quote}dense{close_quote}{close_quote} decorations which were suggested by packing considerations. (iv) Our results depended on using the realistic potentials; {ital short}-range potentials favor the {open_quote}{open_quote}dense{close_quote}{close_quote} structures, and many details depend on the second or further oscillations in the potentials. (v) For our best model, there is relatively little variation of the energy when tiles are rearranged, i.e., a {ital random}-{ital tiling} {ital model} is a good zero-order description of the system. {copyright} {ital 1996 The American Physical Society.}

  11. An inducible transgenic mouse model for familial hypertension with hyperkalaemia (Gordon's syndrome or pseudohypoaldosteronism type II).

    PubMed

    Chowdhury, Jabed A; Liu, Che-Hsiung; Zuber, Annie M; O'Shaughnessy, Kevin M

    2013-06-01

    Mutations in the novel serine/threonine WNK [With No lysine (=K)] kinases WNK1 and WNK4 cause PHAII (pseudohypoaldosteronism type II or Gordon's syndrome), a rare monogenic syndrome which causes hypertension and hyperkalaemia on a background of a normal glomerular filtration rate. Current animal models for PHAII recapitulate some aspects of the disease phenotype, but give no clues to how rapidly the phenotype emerges or whether it is reversible. To this end we have created an inducible PHAII transgenic animal model that expresses a human disease-causing WNK4 mutation, WNK4 Q565E, under the control of the Tet-On system. Several PHAII inducible transgenic mouse lines were created, each with differing TG (transgene) copy numbers and displaying varying degrees of TG expression (low, medium and high). Each of these transgenic lines demonstrated similar elevations of BP (blood pressure) and plasma potassium after 4 weeks of TG induction. Withdrawal of doxycycline switched off mutant TG expression and the disappearance of the PHAII phenotype. Western blotting of microdissected kidney nephron segments confirmed that expression of the thiazide-sensitive NCC (Na⁺-Cl⁻ co-transporter) was increased, as expected, in the distal convoluted tubule when transgenic mice were induced with doxycycline. The kidneys of these mice also do not show the morphological changes seen in the previous transgenic model expressing the same mutant form of WNK4. This inducible model shows, for the first time, that in vivo expression of a mutant WNK4 protein is sufficient to cause the rapid and reversible appearance of a PHAII disease phenotype in mice.

  12. The treatment of mixing in core helium burning models - II. Constraints from cluster star counts

    NASA Astrophysics Data System (ADS)

    Constantino, Thomas; Campbell, Simon W.; Lattanzio, John C.; van Duijneveldt, Adam

    2016-03-01

    The treatment of convective boundaries during core helium burning is a fundamental problem in stellar evolution calculations. In the first paper of this series, we showed that new asteroseismic observations of these stars imply they have either very large convective cores or semiconvection/partially mixed zones that trap g modes. We probe this mixing by inferring the relative lifetimes of asymptotic giant branch (AGB) and horizontal branch (HB) from R2, the observed ratio of these stars in recent HST photometry of 48 Galactic globular clusters. Our new determinations of R2 are more self-consistent than those of previous studies and our overall calculation of R2 = 0.117 ± 0.005 is the most statistically robust now available. We also establish that the luminosity difference between the HB and the AGB clump is Δ log {L}_HB^AGB = 0.455 ± 0.012. Our results accord with earlier findings that standard models predict a lower R2 than is observed. We demonstrate that the dominant sources of uncertainty in models are the prescription for mixing and the stochastic effects that can result from its numerical treatment. The luminosity probability density functions that we derive from observations feature a sharp peak near the AGB clump. This constitutes a strong new argument against core breathing pulses, which broaden the predicted width of the peak. We conclude that the two mixing schemes that can match the asteroseismology are capable of matching globular cluster observations, but only if (i) core breathing pulses are avoided in models with a semiconvection/partially mixed zone, or (ii) that models with large convective cores have a particular depth of mixing beneath the Schwarzschild boundary during subsequent early-AGB `gravonuclear' convection.

  13. Simulation and modeling of the Gamble II self-pinched ion beam transport experiment

    SciTech Connect

    Rose, D.V.; Ottinger, P.F.; Hinshelwood, D.D.

    1999-07-01

    Progress in numerical simulations and modeling of the self-pinched ion beam transport experiment at the Naval Research Laboratory (NRL) is reviewed. In the experiment, a 1.2-MeV, 100-kA proton beam enters a 1-m long, transport region filled with a low pressure gas (30--250 mTorr helium, or 1 Torr air). The time-dependent velocity distribution function of the injected ion beam is determined from an orbit code that uses a pinch-reflex ion diode model and the measured voltage and current from this diode on the Gamble II generator at NRL. This distribution function is used as the beam input condition for numerical simulations carried out using the hybrid particle-in-cell code IPROP. Results of the simulations will be described, and detailed comparisons will be made with various measurements, including line-integrated electron-density, proton-fluence, and beam radial-profile measurements. As observed in the experiment, the simulations show evidence of self-pinching for helium pressures between 35 and 80 mTorr. Simulations and measurements in 1 Torr air show ballistic transport. The relevance of these results to ion-driven inertial confinement fusion will be discussed.

  14. Infertility and recurrent miscarriage with complex II deficiency-dependent mitochondrial oxidative stress in animal models.

    PubMed

    Ishii, Takamasa; Yasuda, Kayo; Miyazawa, Masaki; Mitsushita, Junji; Johnson, Thomas E; Hartman, Phil S; Ishii, Naoaki

    2016-04-01

    Oxidative stress is associated with some forms of both male and female infertility. However, there is insufficient knowledge of the influence of oxidative stress on the maintenance of a viable pregnancy, including pregnancy complications and fetal development. There are a number of animal models for understanding age-dependent decrease of reproductive ability and diabetic embryopathy, especially abnormal spermatogenesis, oogenesis and embryogenesis with mitochondrial dysfunctions. Several important processes occur in mitochondria, including ATP synthesis, calcium ion storage, induction of apoptosis and production of reactive oxygen species (ROS). These events have different effects on the several aspects of reproductive function. Tet-mev-1 conditional transgenic mice, developed after studies with the mev-1 mutant of the nematode C. elegans, offer the ability to carefully regulate expression of doxycycline-induced mutated SDHC(V69E) levels and hence modulate endogenous oxidative stress. The mev-1 models have served to illuminate the effects of complex II deficiency-dependent mitochondrial ROS production, although interestingly they maintain normal mitochondrial and intracellular ATP levels. In this review, the reproductive dysfunctions are presented focusing on fertility potentials in each gamete, early embryogenesis, maternal conditions with placental function and neonatal development.

  15. CBSD Version II component models of the IR celestial background. Technical report

    SciTech Connect

    Kennealy, J.P.; Glaudell, G.A.

    1990-12-07

    CBSD Version II addresses the development of algorithms and software which implement realistic models of all the primary celestial background phenomenologies, including solar system, galactic, and extra-galactic features. During 1990, the CBSD program developed and refined IR scene generation models for the zodiacal emission, thermal emission from asteroids and planets, and the galactic point source background. Chapters in this report are devoted to each of those areas. Ongoing extensions to the point source module for extended source descriptions of nebulae and HII regions are briefly discussed. Treatment of small galaxies will also be a natural extension of the current CBSD point source module. Although no CBSD module yet exists for interstellar IR cirrus, MRC has been working closely with the Royal Aerospace Establishment in England to achieve a data-base understanding of cirrus fractal characteristics. The CBSD modules discussed in Chapters 2, 3, and 4 are all now operational and have been employed to generate a significant variety of scenes. CBSD scene generation capability has been well accepted by both the IR astronomy community and the DOD user community and directly supports the SDIO SSGM program.

  16. [Opiate dependence type II or antisocial: Cloninger's Psychobiological Model and its usefullness in addictions].

    PubMed

    Benito, Ana; Haro, Gonzalo; Orengo, Teresa; González, Marisa; Fornés, Teresa; Mateu, César

    2012-01-01

    The aim was to analyze the relationship between Cloninger's dimensions and Personality Disorders (PD) (with DSM-IV criteria) in opiate dependents. The study was Cross-sectional. The sampling of 196 patients with opiate dependence was consecutive. All were receiving treatment in an inpatient detoxification unit. Cloninger's Temperament and Character Inventory (TCI), International Personality Disorders Examination (IPDE) and a Substance Use Questionnaire were used. Character's dimensions as Self-directness and Cooperation were related with PD when scored low. Opposite to Cloninger descriptions, high scores of Self-transcendence were related with presence of PD. Related to temperamental dimensions, cluster A was related with low scores of Reward Dependence (RD) and cluster C with high scores of Harm Avoidance (HA). Otherwise, in cluster B, while Borderline PD had high scores of Novelty Seeking (as high HA), the Antisocial PD only were related to low scores of RD. RD dimension seems useful to differ from presence or absence of Antisocial PD, also when alcohol consumption is considered. Cloninger's Model of Personality is useful in drug dependents for the definition of the different PD, as well as for probable PD's aggregation. This model also helps to create subtypes in opiate dependents as the antisocial or type II.

  17. Atlantic-Arctic exchange in a series of ocean model simulations (CORE-II)

    NASA Astrophysics Data System (ADS)

    Roth, Christina; Behrens, Erik; Biastoch, Arne

    2014-05-01

    In this study we aim to improve the understanding of exchange processes between the North Atlantic and the Arctic Ocean. The Nordic Sea builds an important connector between these regions, by receiving and modifying warm and saline Atlantic waters, and by providing dense overflow as a backbone of the Atlantic Meridional Overturning Circulation (AMOC). Using a hierarchy of global ocean/sea-ice models, the specific role of the Nordic Seas, both providing a feedback with the AMOC, but also as a modulator of the Atlantic water flowing into the Arctic Ocean, is examined. The models have been performed under the CORE-II protocol, in which atmospheric forcing of the past 60 years was applied in a subsequent series of 5 iterations. During the course of this 300-year long integration, the AMOC shows substantial changes, which are correlated with water mass characteristics in the Denmark Strait overflow characteristics. Quantitative analyses using Lagrangian trajectories explore the impact of these trends on the Arctic Ocean through the Barents Sea and the Fram Strait.

  18. Analysis of TOPAZ II and SPACE-R space nuclear power plants using a modified thermionic model. Master's thesis

    SciTech Connect

    Habedank, O.D.

    1993-03-01

    Models based on the TDS thermionic diode model were developed for TOPAZ II and SPACER nuclear power systems. Several parameter studies were conducted with the TOPAZ II model. These determined system performance and efficiency while varying the following: (1) Coolant flow inlet temperatures. (2) Rate of coolant temperature change. (3) Power profile of the core. (4) Cesium reservoir temperature. Analysis of results indicate the model accurately represented the TOPAZ II system, underestimating published data by 10%. Coolant flow studies indicate that raising coolant temperatures up to 100 K higher increases system power by up to 5%. Additional increases in temperature result in gradual performance degradation. Varying the axial power profile of the core from the actual peaked profile to a flat profile results in a negligible 0.3% change in system performance. The peaked profile used in TOPAZ II produces the highest system efficiency of all the profiles modeled. The cesium pressure study indicates the system is operating above optimum cesium pressure and system performance is strongly dependent on cesium pressure. Increasing cesium reservoir temperature above design temperature by 30 K decreases system efficiency by 30%.

  19. A Pressure-dependent Model for the Regulation of Lipoprotein Lipase by Apolipoprotein C-II.

    PubMed

    Meyers, Nathan L; Larsson, Mikael; Olivecrona, Gunilla; Small, Donald M

    2015-07-17

    Apolipoprotein C-II (apoC-II) is the co-factor for lipoprotein lipase (LPL) at the surface of triacylglycerol-rich lipoproteins. LPL hydrolyzes triacylglycerol, which increases local surface pressure as surface area decreases and amphipathic products transiently accumulate at the lipoprotein surface. To understand how apoC-II adapts to these pressure changes, we characterized the behavior of apoC-II at multiple lipid/water interfaces. ApoC-II adsorption to a triacylglycerol/water interface resulted in large increases in surface pressure. ApoC-II was exchangeable at this interface and desorbed on interfacial compressions. These compressions increase surface pressure and mimic the action of LPL. Analysis of gradual compressions showed that apoC-II undergoes a two-step desorption, which indicates that lipid-bound apoC-II can exhibit at least two conformations. We characterized apoC-II at phospholipid/triacylglycerol/water interfaces, which more closely mimic lipoprotein surfaces. ApoC-II had a large exclusion pressure, similar to that of apoC-I and apoC-III. However, apoC-II desorbed at retention pressures higher than those seen with the other apoCs. This suggests that it is unlikely that apoC-I and apoC-III inhibit LPL via displacement of apoC-II from the lipoprotein surface. Upon rapid compressions and re-expansions, re-adsorption of apoC-II increased pressure by lower amounts than its initial adsorption. This indicates that apoC-II removed phospholipid from the interface upon desorption. These results suggest that apoC-II regulates the activity of LPL in a pressure-dependent manner. ApoC-II is provided as a component of triacylglycerol-rich lipoproteins and is the co-factor for LPL as pressure increases. Above its retention pressure, apoC-II desorbs and removes phospholipid. This triggers release of LPL from lipoproteins.

  20. A Pressure-dependent Model for the Regulation of Lipoprotein Lipase by Apolipoprotein C-II*

    PubMed Central

    Meyers, Nathan L.; Larsson, Mikael; Olivecrona, Gunilla; Small, Donald M.

    2015-01-01

    Apolipoprotein C-II (apoC-II) is the co-factor for lipoprotein lipase (LPL) at the surface of triacylglycerol-rich lipoproteins. LPL hydrolyzes triacylglycerol, which increases local surface pressure as surface area decreases and amphipathic products transiently accumulate at the lipoprotein surface. To understand how apoC-II adapts to these pressure changes, we characterized the behavior of apoC-II at multiple lipid/water interfaces. ApoC-II adsorption to a triacylglycerol/water interface resulted in large increases in surface pressure. ApoC-II was exchangeable at this interface and desorbed on interfacial compressions. These compressions increase surface pressure and mimic the action of LPL. Analysis of gradual compressions showed that apoC-II undergoes a two-step desorption, which indicates that lipid-bound apoC-II can exhibit at least two conformations. We characterized apoC-II at phospholipid/triacylglycerol/water interfaces, which more closely mimic lipoprotein surfaces. ApoC-II had a large exclusion pressure, similar to that of apoC-I and apoC-III. However, apoC-II desorbed at retention pressures higher than those seen with the other apoCs. This suggests that it is unlikely that apoC-I and apoC-III inhibit LPL via displacement of apoC-II from the lipoprotein surface. Upon rapid compressions and re-expansions, re-adsorption of apoC-II increased pressure by lower amounts than its initial adsorption. This indicates that apoC-II removed phospholipid from the interface upon desorption. These results suggest that apoC-II regulates the activity of LPL in a pressure-dependent manner. ApoC-II is provided as a component of triacylglycerol-rich lipoproteins and is the co-factor for LPL as pressure increases. Above its retention pressure, apoC-II desorbs and removes phospholipid. This triggers release of LPL from lipoproteins. PMID:26026161

  1. Radiation induced secretion of surfactant from cell cultures of type II pneumocytes: an in vitro model of radiation toxicity

    SciTech Connect

    Shapiro, D.L.; Finkelstein, J.N.; Rubin, P.; Penney, D.P.; Siemann, D.W.

    1984-03-01

    The pathogenesis of pneumonitis and fibrosis secondary to lung irradiation is incompletely understood. The role of the type II alveolar epithelial pneumocyte in these processes has been under investigation. The type II pneumocyte has been shown in vivo to respond to radiation induced injury with release of pulmonary surfactant. The effect of irradiation on cell cultures of type II pneumocytes was studied to determine if this could be reproduced in vitro. Type II pneumocytes were found to release surfactant material with a threshold of radiation dose between 1000 and 1500 rad. This is similar to the dosage range over which the same effect has been demonstrated in vivo. Experimental results support the concept that the release of surfactant is not due to either cell disruption or non-specific release of phospholipid from cell membranes. Irradiation appears to trigger membrane receptor mediated surfactant release. In addition, irradiation abolishes the ability of cells to subsequently respond to a physiologic agonist, suggesting radiation induced damage to the secretory mechanism. These studies establish that surfactant release in response to irradiation in vivo is a direct effect on type II pneumocytes. Cell cultures of type II pneumocytes can serve as a laboratory model of lung cell radiation toxicity.

  2. Equilibrium and kinetic modelling of cadmium(II) biosorption by nonliving algal biomass Oedogonium sp. from aqueous phase.

    PubMed

    Gupta, V K; Rastogi, A

    2008-05-01

    The biosorption of cadmium(II) ions on Oedogonium sp. is studied in a batch system with respect to initial pH, algal dose, contact time and the temperature. The algal biomass exhibited the highest cadmium(II) uptake capacity at 25 degrees C, at the initial pH value of 5.0 in 55 min and at the initial cadmium(II) ion concentration of 200 mg L(-1). Biosorption capacity decreased from 88.9 to 80.4 mg g(-1) with an increase in temperature from 25 to 45 degrees C at this initial cadmium(II) concentration. Uptake kinetics follows the pseudo-second-order model and equilibrium is well described by Langmuir isotherm. Isotherms have been used to determine thermodynamic parameters of the process, viz., free energy change, enthalpy change and entropy change. FTIR analysis of algal biomass revealed the presence of amino, carboxyl, hydroxyl and carbonyl groups, which are responsible for biosorption of metal ions. Acid pretreatments did not substantially increase metal sorption capacity but alkali like NaOH pretreatment slightly enhanced the metal removal ability of the biomass. During repeated sorption/desorption cycles at the end of fifth cycle, Cd(II) sorption decreased by 18%, with 15-20% loss of biomass. Nevertheless, Oedogonium sp. appears to be a good sorbent for removing metal Cd(II) from aqueous phase.

  3. Kinetic and isotherm modeling of Cd (II) adsorption by L-cysteine functionalized multi-walled carbon nanotubes as adsorbent.

    PubMed

    Taghavi, Mahmoud; Zazouli, Mohammad Ali; Yousefi, Zabihollah; Akbari-adergani, Behrouz

    2015-11-01

    In this study, multi-walled carbon nanotubes were functionalized by L-cysteine to show the kinetic and isotherm modeling of Cd (II) ions onto L-cysteine functionalized multi-walled carbon nanotubes. The adsorption behavior of Cd (II) ion was studied by varying parameters including dose of L-MWCNTs, contact time, and cadmium concentration. Equilibrium adsorption isotherms and kinetics were also investigated based on Cd (II) adsorption tests. The results showed that an increase in contact time and adsorbent dosage resulted in increase of the adsorption rate. The optimum condition of the Cd (II) removal process was found at pH=7.0, 15 mg/L L-MWCNTs dosage, 6 mg/L cadmium concentration, and contact time of 60 min. The removal percent was equal to 89.56 at optimum condition. Langmuir and Freundlich models were employed to analyze the experimental data. The data showed well fitting with the Langmuir model (R2=0.994) with q max of 43.47 mg/g. Analyzing the kinetic data by the pseudo-first-order and pseudo-second-order equations revealed that the adsorption of cadmium using L-MWSNTs following the pseudo-second-order kinetic model with correlation coefficients (R2) equals to 0.998, 0.992, and 0.998 for 3, 6, and 9 mg/L Cd (II) concentrations, respectively. The experimental data fitted very well with the pseudo-second-order. Overall, treatment of polluted solution to Cd (II) by adsorption process using L-MWCNT can be considered as an effective technology.

  4. Experiment, modeling and optimization of liquid phase adsorption of Cu(II) using dried and carbonized biomass of Lyngbya majuscula

    NASA Astrophysics Data System (ADS)

    Kushwaha, Deepika; Dutta, Susmita

    2017-05-01

    The present work aims at evaluation of the potential of cyanobacterial biomass to remove Cu(II) from simulated wastewater. Both dried and carbonized forms of Lyngbya majuscula, a cyanobacterial strain, have been used for such purpose. The influences of different experimental parameters viz., initial Cu(II) concentration, solution pH and adsorbent dose have been examined on sorption of Cu(II). Kinetic and equilibrium studies on Cu(II) removal from simulated wastewater have been done using both dried and carbonized biomass individually. Pseudo-second-order model and Langmuir isotherm have been found to fit most satisfactorily to the kinetic and equilibrium data, respectively. Maximum 87.99 and 99.15 % of Cu(II) removal have been achieved with initial Cu(II) concentration of 10 and 25 mg/L for dried and carbonized algae, respectively, at an adsorbent dose of 10 g/L for 20 min of contact time and optimum pH 6. To optimize the removal process, Response Surface Methodology has been employed using both the dried and carbonized biomass. Removal with initial Cu(II) concentration of 20 mg/L, with 0.25 g adsorbent dose in 50 mL solution at pH 6 has been found to be optimum with both the adsorbents. This is the first ever attempt to make a comparative study on Cu(II) removal using both dried algal biomass and its activated carbon. Furthermore, regeneration of matrix was attempted and more than 70% and 80% of the adsorbent has been regenerated successfully in the case of dried and carbonized biomass respectively upto the 3rd cycle of regeneration study.

  5. Experiment, modeling and optimization of liquid phase adsorption of Cu(II) using dried and carbonized biomass of Lyngbya majuscula

    NASA Astrophysics Data System (ADS)

    Kushwaha, Deepika; Dutta, Susmita

    2015-07-01

    The present work aims at evaluation of the potential of cyanobacterial biomass to remove Cu(II) from simulated wastewater. Both dried and carbonized forms of Lyngbya majuscula, a cyanobacterial strain, have been used for such purpose. The influences of different experimental parameters viz., initial Cu(II) concentration, solution pH and adsorbent dose have been examined on sorption of Cu(II). Kinetic and equilibrium studies on Cu(II) removal from simulated wastewater have been done using both dried and carbonized biomass individually. Pseudo-second-order model and Langmuir isotherm have been found to fit most satisfactorily to the kinetic and equilibrium data, respectively. Maximum 87.99 and 99.15 % of Cu(II) removal have been achieved with initial Cu(II) concentration of 10 and 25 mg/L for dried and carbonized algae, respectively, at an adsorbent dose of 10 g/L for 20 min of contact time and optimum pH 6. To optimize the removal process, Response Surface Methodology has been employed using both the dried and carbonized biomass. Removal with initial Cu(II) concentration of 20 mg/L, with 0.25 g adsorbent dose in 50 mL solution at pH 6 has been found to be optimum with both the adsorbents. This is the first ever attempt to make a comparative study on Cu(II) removal using both dried algal biomass and its activated carbon. Furthermore, regeneration of matrix was attempted and more than 70% and 80% of the adsorbent has been regenerated successfully in the case of dried and carbonized biomass respectively upto the 3rd cycle of regeneration study.

  6. INFLUENCE OF TYPE II DIABETES, OBESITY, AND EXPOSURE TO 2, 3, 7, 8-TETRACHLORODIBENZO-P-DIOXIN (TCDD) EXPOSURE ON THE EXPRESSION OF HEPATIC CYP1A2 IN A MURIN MODEL OF TYPE II DIABETES

    EPA Science Inventory

    Influence of type II diabetes, obesity and exposure 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure on the expression of hepatic CYPIA2 in a murine model of type II diabetes. SJ Godin', VM Richardson2, JJ Diliberto2, LS Birnbaum', MJ DeVito2; 'Curriculum In Toxicology, UNC-CH...

  7. INFLUENCE OF TYPE II DIABETES, OBESITY, AND EXPOSURE TO 2, 3, 7, 8-TETRACHLORODIBENZO-P-DIOXIN (TCDD) EXPOSURE ON THE EXPRESSION OF HEPATIC CYP1A2 IN A MURIN MODEL OF TYPE II DIABETES

    EPA Science Inventory

    Influence of type II diabetes, obesity and exposure 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure on the expression of hepatic CYPIA2 in a murine model of type II diabetes. SJ Godin', VM Richardson2, JJ Diliberto2, LS Birnbaum', MJ DeVito2; 'Curriculum In Toxicology, UNC-CH...

  8. A model of large-scale instabilities in the Jovian troposphere. I - Linear model. II - Quasi-linear model

    NASA Astrophysics Data System (ADS)

    Orsolini, Y.; Leovy, C. B.

    1993-12-01

    A quasi-geostrophic midlatitude beta-plane linear model is here used to study whether the decay with height and meridional circulations of near-steady jets in the tropospheric circulation of Jupiter arise as a means of stabilizing a deep zonal flow that extends into the upper troposphere. The model results obtained are analogous to the stabilizing effect of meridional shear on baroclinic instabilities. In the second part of this work, a quasi-linear model is used to investigate how an initially barotropically unstable flow develops a quasi-steady shear zone in the lower scale heights of the model domain, due to the action of the eddy fluxes.

  9. Modeling and control of tubular solid-oxide fuel cell systems: II. Nonlinear model reduction and model predictive control

    NASA Astrophysics Data System (ADS)

    Sanandaji, Borhan M.; Vincent, Tyrone L.; Colclasure, Andrew M.; Kee, Robert J.

    This paper describes a systematic method for developing model-based controllers for solid-oxide fuel cell (SOFC) systems. To enhance the system efficiency and to avoid possible damages, the system must be controlled within specific operating conditions, while satisfying a load requirement. Model predictive control (MPC) is a natural choice for control implementation. However, to implement MPC, a low-order model is needed that captures the dominant dynamic behavior over the operating range. A linear parameter varying (LPV) model structure is developed and applied to obtain a control-oriented dynamic model of the SOFC stack. This approach effectively reduces a detailed physical model to a form that is compatible with MPC. The LPV structure includes nonlinear scheduling functions that blend the dynamics of locally linear models to represent nonlinear dynamic behavior over large operating ranges. Alternative scheduling variables are evaluated, with cell current being shown to be an appropriate choice. Using the reduced-order model, an MPC controller is designed that can respond to the load requirement over a wide range of operation changes while maintaining input-output variables within specified constraints. To validate the approach, the LPV-based MPC controller is applied to the high-order physical model.

  10. Coordination of two high-affinity hexamer peptides to copper(II) and palladium(II) models of the peptide-metal chelation site on IMAC resins

    SciTech Connect

    Chen, Y.; Pasquinelli, R.; Ataai, M.; Koepsel, R.R.; Kortes, R.A.; Shepherd, R.E.

    2000-03-20

    The coordination of peptides Ser-Pro-His-His-Gly-Gly (SPHHGG) and (His){sub 6} (HHHHHH) to [Pd{sup II}(mida)(D{sub 2}O)] (mida{sup 2{minus}} = N-methyliminodiacetate) was studied by {sup 1}H NMR as model reactions for Cu{sup II}(iminodiacetate)-immobilized metal affinity chromatography (IMAC) sites. This is the first direct physical description of peptide coordination for IMAC. A three-site coordination is observed which involves the first, third, and fourth residues along the peptide chain. The presence of proline in position 2 of SPHHGG achieves the best molecular mechanics and bonding angles in the coordinated peptide and enhances the interaction of the serine amino nitrogen. Histidine coordination of H{sub 1}, H{sub 3}, and H{sub 4} of (His){sub 6} and H{sub 3} and H{sub 4} of SPHHGG was detected by {sup 1}H NMR contact shifts and H/D exchange of histidyl protons. The EPR spectra of SPHHGG and HHHHHH attached to the [Cu{sup II}(mida)] unit were obtained for additional modeling of IMAC sites. EPR parameters of the parent [Cu(mida)(H{sub 2}O){sub 2}] complex are representative: g{sub zz} = 2.31; g{sub yy} = 2.086; g{sub xx} = 2.053; A{sub {vert_bar}{vert_bar}} = 161 G; A{sub N} = 19G (three line, one N coupling). Increased rhombic distortion is detected relative to the starting aqua complex in the order of [Cu(mida)L] for distortion of HHHHHH > SPHHGG > (H{sub 2}O){sub 2}. The lowering of symmetry is also seen in the decrease in the N-shf coupling, presumably to the imino nitrogen of mida{sup 2{minus}} in the order 19 G (H{sub 2}O), 16 G (SPHHGG) and 11 G (HHHHHH). Visible spectra of the [Cu(mida)(SPHHGG)] and [Cu(mida)(HHHHHH)] as a function of pH indicate coordination of one histidyl donor at ca. 4.5, two in the range of pH 5--7, and two chelate ring attachments involving the terminal amino donor for SPHHGG or another histidyl donor of HHHHHH in the pH domain of 7--8 in agreement with the [Pd{sup II}(mida)L] derivatives which form the two

  11. A simple model for polyproline II structure in unfolded states of alanine-based peptides

    PubMed Central

    Pappu, Rohit V.; Rose, George D.

    2002-01-01

    The striking similarity between observed circular dichroism spectra of nonprolyl homopolymers and that of regular left-handed polyproline II (PII) helices prompted Tiffany and Krimm to propose in 1968 that unordered peptides and unfolded proteins are built of PII segments linked by sharp bends. A large body of experimental evidence, accumulated over the past three decades, provides compelling evidence in support of the original hypothesis of Tiffany and Krimm. Of particular interest are the recent experiments of Shi et al. who find significant PII structure in a short unfolded alanine-based peptide. What is the physical basis for PII helices in peptide and protein unfolded states? The widely accepted view is that favorable chain-solvent hydrogen bonds lead to a preference for dynamical fluctuations about noncooperative PII helices in water. Is this preference simply a consequence of hydrogen bonding or is it a manifestation of a more general trend for unfolded states which are appropriately viewed as chains in a good solvent? The prevalence of closely packed interiors in folded proteins suggests that under conditions that favor folding, water—which is a better solvent for itself than for any polypeptide chain—expels the chain from its midst, thereby maximizing chain packing. Implicit in this view is a complementary idea: under conditions that favor unfolding, chain-solvent interactions are preferred and in a so-called good solvent, chain packing density is minimized. In this work we show that minimization of chain packing density leads to preferred fluctuations for short polyalanyl chains around canonical, noncooperative PII-like conformations. Minimization of chain packing is modeled using a purely repulsive soft-core potential between polypeptide atoms. Details of chain-solvent interactions are ignored. Remarkably, the simple model captures the essential physics behind the preference of short unfolded alanine-based peptides for PII helices. Our results are

  12. Model based design and analysis of phase II HIV-1 trials.

    PubMed

    Rekić, Dinko; Röshammar, Daniel; Simonsson, Ulrika S H

    2013-08-01

    This work explores the advantages of a model based drug development (MBDD) approach for the design and analysis of antiretroviral phase II trials. Two different study settings were investigated: (1) a 5-arm placebo-controlled parallel group dose-finding/proof of concept (POC) study and (2) a comparison of investigational drug and competitor. Studies were simulated using a HIV-1 dynamics model in NONMEM. The Monte-Carlo Mapped Power method determined the sample size required for detecting a dose-response relationship and a significant difference in effect compared to the competitor using a MBDD approach. Stochastic simulation and re-estimation were used for evaluation of model parameter precision and bias given different sample sizes. Results were compared to those from an unpaired, two-sided t test and ANOVA (p ≤ 0.05). In all scenarios, the MBDD approach resulted in smaller study sizes and more precisely estimated treatment effect than conventional statistical analysis. Using a MBDD approach, a sample size of 15 patients could be used to show POC and estimate ED50 with a good precision (relative standard error, 25.7 %). A sample size of 10 patients per arm was needed using the MBDD approach for detecting a difference in treatment effect of ≥20 % at 80 % power, a 3.4-fold reduction in sample size compared to a t test. The MBDD approach can be used to achieve more precise dose-response characterization facilitating decision making and dose selection. If necessitated, the sample size needed to reach a desired power can potentially be reduced compared to traditional statistical analyses. This may allow for comparison against competitors already in early clinical studies.

  13. Dinuclear zinc(II) complexes with hydrogen bond donors as structural and functional phosphatase models.

    PubMed

    Bosch, Simone; Comba, Peter; Gahan, Lawrence R; Schenk, Gerhard

    2014-09-02

    It is becoming increasingly apparent that the secondary coordination sphere can have a crucial role in determining the functional properties of biomimetic metal complexes. We have therefore designed and prepared a variety of ligands as metallo-hydrolase mimics, where hydrogen bonding in the second coordination sphere is able to influence the structure of the primary coordination sphere and the substrate binding. The assessment of a structure-function relationship is based on derivates of 2,6-bis{[bis(pyridin-2-ylmethyl)amino]methyl}-4-methylphenol (HBPMP = HL(1)) and 2-{[bis(pyridin-2-ylmethyl)amino]methyl}-6-{[(2-hydroxybenzyl)(pyridin-2-ylmethyl)amino]methyl}-4-methylphenol (H2BPBPMP = H2L(5)), well-known phenolate-based ligands for metallo-hydrolase mimics. The model systems provide similar primary coordination spheres but site-specific modifications in the secondary coordination sphere. Pivaloylamide and amine moieties were chosen to mimic the secondary coordination sphere of the phosphatase models, and the four new ligands H3L(2), H3L(3), HL(4), and H4L(6) vary in the type and geometric position of the H-bond donors and acceptors, responsible for the positioning of the substrate and release of the product molecules. Five dinuclear Zn(II) complexes were prepared and structurally characterized in the solid, and four also in solution. The investigation of the phosphatase activity of four model complexes illustrates the impact of the H-bonding network: the Michaelis-Menten constants (catalyst-substrate binding) for all complexes that support hydrogen bonding are smaller than for the reference complex, and this generally leads to higher catalytic efficiency and higher turnover numbers.

  14. Decays of bottom mesons emitting tensor mesons in the final state using the Isgur-Scora-Grinstein-Wise II model

    SciTech Connect

    Sharma, Neelesh; Verma, R. C.; Dhir, Rohit

    2011-01-01

    In this paper, we investigate phenomenologically two-body weak decays of the bottom mesons emitting pseudoscalar/vector meson and a tensor meson. Form factors are obtained using the improved Isgur-Scora-Grinstein-Wise II model. Consequently, branching ratios for the Cabibbo-Kobayashi-Maskawa-favored and Cabibbo-Kobayashi-Maskawa-suppressed decays are calculated.

  15. Comprehensive Study of Educational Technology Programs Authorized from 1989-1992. Volume III: Level II Model Technology School Projects.

    ERIC Educational Resources Information Center

    Far West Lab. for Educational Research and Development, San Francisco, CA.

    This report, the third in a series of six, evaluates the 10 school districts that received grants from the California Department of Education to develop Level II Model Technology School (MTS) Projects intended to enhance instruction and student learning through a combination of curriculum improvement and integration of technology within a single…

  16. A Test of Three Basic Assumptions of Situational Leadership® II Model and Their Implications for HRD Practitioners

    ERIC Educational Resources Information Center

    Zigarmi, Drea; Roberts, Taylor Peyton

    2017-01-01

    Purpose: This study aims to test the following three assertions underlying the Situational Leadership® II (SLII) Model: all four leadership styles are received by followers; all four leadership styles are needed by followers; and if there is a fit between the leadership style a follower receives and needs, that follower will demonstrate favorable…

  17. Model I & II Organizations: Examining Organizational Learning in Institutions Participating in the Academy for the Assessment of Student Learning

    ERIC Educational Resources Information Center

    Haywood, Antwione Maurice

    2012-01-01

    The Academy was an assessment enhancement program created by the HLC to help institutions strengthen and improve the assessment of student learning. Using a multiple case study approach, this study applies Argyis and Schon's (1976) Theory of Action to explore the espoused values and existence of Model I and II behavior characteristics. Argyis…

  18. Comprehensive Study of Educational Technology Programs Authorized from 1989-1992. Volume II: Model Technology Schools, Level I.

    ERIC Educational Resources Information Center

    Far West Lab. for Educational Research and Development, San Francisco, CA.

    This report, the second in a series of six, presents the findings of evaluative studies of six Level I Model Technology School sites which were conducted as part of Phase II of the California Educational Technology Assessment Program. The project sites are: Alhambra City School District (two schools); Cupertino Union Elementary District and…

  19. IGF-II promotes neuroprotection and neuroplasticity recovery in a long-lasting model of oxidative damage induced by glucocorticoids.

    PubMed

    Martín-Montañez, E; Millon, C; Boraldi, F; Garcia-Guirado, F; Pedraza, C; Lara, E; Santin, L J; Pavia, J; Garcia-Fernandez, M

    2017-10-01

    Insulin-like growth factor-II (IGF-II) is a naturally occurring hormone that exerts neurotrophic and neuroprotective properties in a wide range of neurodegenerative diseases and ageing. Accumulating evidence suggests that the effects of IGF-II in the brain may be explained by its binding to the specific transmembrane receptor, IGFII/M6P receptor (IGF-IIR). However, relatively little is known regarding the role of IGF-II through IGF-IIR in neuroprotection. Here, using adult cortical neuronal cultures, we investigated whether IGF-II exhibits long-term antioxidant effects and neuroprotection at the synaptic level after oxidative damage induced by high and transient levels of corticosterone (CORT). Furthermore, the involvement of the IGF-IIR was also studied to elucidate its role in the neuroprotective actions of IGF-II. We found that neurons treated with IGF-II after CORT incubation showed reduced oxidative stress damage and recovered antioxidant status (normalized total antioxidant status, lipid hydroperoxides and NAD(P) H:quinone oxidoreductase activity). Similar results were obtained when mitochondria function was analysed (cytochrome c oxidase activity, mitochondrial membrane potential and subcellular mitochondrial distribution). Furthermore, neuronal impairment and degeneration were also assessed (synaptophysin and PSD-95 expression, presynaptic function and FluoroJade B® stain). IGF-II was also able to recover the long-lasting neuronal cell damage. Finally, the effects of IGF-II were not blocked by an IGF-IR antagonist, suggesting the involvement of IGF-IIR. Altogether these results suggest that, in or model, IGF-II through IGF-IIR is able to revert the oxidative damage induced by CORT. In accordance with the neuroprotective role of the IGF-II/IGF-IIR reported in our study, pharmacotherapy approaches targeting this pathway may be useful for the treatment of diseases associated with cognitive deficits (i.e., neurodegenerative disorders, depression, etc

  20. Modeling ecological data in soil ecosystems: A demonstration for heavy metal transport by earthworms using Stella II{trademark}

    SciTech Connect

    Johnston, J.M.; Tomlin, A.D.; Protz, R. ||

    1995-06-01

    Various modeling approaches have been developed for use in aquatic systems, but few exist for terrestrial systems. Using the modeling application software, Stella II{trademark}, we incorporated field data to parameterize the storage compartments and flux rates amongst compartments. This software is intuitive and easy to master yet robust in its application to many types of ecological systems. The applicability of Stella II{trademark} to modeling field data was demonstrated using contaminant cadmium residues as tracers of sludge applications to land near Guelph, Canada. Earthworms were found to be very significant in transporting the Cd (and the sludge) in this soil ecosystem. The utility of this modeling procedure can be extended to carbon and nutrient cycling as well as xenobiotics such as heavy metals and pesticides to predict their transport in soil ecosystems.

  1. Aversive and non-aversive memory impairment in the mucopolysaccharidosis II mouse model.

    PubMed

    Azambuja, Amanda Stapenhorst; Correa, Lilian; Gabiatti, Bernardo Pappi; Martins, Giselle Renata; de Oliveira Franco, Álvaro; Ribeiro, Maria Flávia Marques; Baldo, Guilherme

    2017-09-16

    Hunter syndrome (MPS II, OMIM 309900) is a lysosomal storage disorder due to deficient iduronate sulphatase activity. Patients present multiple cognitive alterations, and the aim of this work was to verify if MPS II mice also present some progressive cognitive alterations. For that, MPS II mice from 2 to 6 months of age were submitted to repeated open field and inhibitory avoidance tests to evaluate memory parameters. MPS II mice presented impaired memory at 6 months evaluated by open field test. They also performed poorly in the inhibitory avoidance test from 4 months. We conclude that MPS II mice develop cognitive alterations as the disease progresses. These tests can be used in the future to study the efficacy of therapeutic approaches in the central nervous system.

  2. CHROMOSPHERIC DIAGNOSIS WITH Ca II LINES: FORWARD MODELING IN FORWARD SCATTERING. I

    SciTech Connect

    Carlin, E. S.; Ramos, A. Asensio

    2015-03-01

    This paper presents a synthetic tomography of the quiet solar chromosphere formed by spatial maps of scattering polarization. It has been calculated for the Ca II 8498, 8542, and 3934 Å lines by solving the non-LTE radiative transfer problem of the second kind in a three-dimensional atmosphere model obtained from realistic magneto-hydrodynamical simulations. Our investigation focuses on the linear polarization signals induced by kinematics, radiation field anisotropy, and the Hanle effect in forward-scattering geometry. Thus, instead of considering slit profiles at the limb as normally done in the study of the second solar spectrum, we synthesize and analyze spatial maps of polarization at the disk center. This allows us to understand the spatial signatures of dynamics and magnetic field in the linear polarization in order to discriminate them observationally. Our results suggest some ideas for chromospheric diagnosis that will be developed throughout a series of papers. In particular, Hanle polarity inversion lines and dynamic Hanle diagrams are two concepts introduced in the present work. We find that chromospheric dynamics and magnetic field topology create spatial polarization fingerprints that trace the dynamic situation of the plasma and the magnetic field. This allows us to reconstruct the magnetic field intensity in the middle chromosphere using Stokes V along grooves of null linear polarization. We finally address the problems of diagnosing Hanle saturation and kinematic amplification of scattering signals using Hanle diagrams.

  3. Outcomes of different Class II treatments : Comparisons using the American Board of Orthodontics Model Grading System.

    PubMed

    Akinci Cansunar, Hatice; Uysal, Tancan

    2016-07-01

    The aim of this study was to evaluate the clinical outcomes of three different Class II treatment modalities followed by fixed orthodontic therapy, using the American Board of Orthodontics Model Grading System (ABO-MGS). As a retrospective study, files of patients treated at postgraduate orthodontic  clinics in different cities in Turkey was randomly selected. From 1684 posttreatment records, 669 patients were divided into three groups: 269 patients treated with extraction of two upper premolars, 198 patients treated with cervical headgear, and 202 patients treated with functional appliances. All the cases were evaluated by one researcher using ABO-MGS. The χ (2), Z test, and multivariate analysis of variance were used for statistical evaluation (p < 0.05). No significant differences were found among the groups in buccolingual inclination, overjet, occlusal relationship, and root angulation. However, there were significant differences in alignment, marginal ridge height, occlusal contact, interproximal contact measurements, and overall MGS average scores. The mean treatment time between the extraction and functional appliance groups was significantly different (p = 0.017). According to total ABO-MGS scores, headgear treatment had better results than functional appliances. The headgear group had better tooth alignment than the extraction group. Headgear treatment resulted in better occlusal contacts than the functional appliances and had lower average scores for interproximal contact measurements. Functional appliances had the worst average scores for marginal ridge height. Finally, the functional appliance group had the longest treatment times.

  4. LASNEX modeling of target expansion in the ETA-II experiment

    SciTech Connect

    Ho, D D-M

    1998-05-20

    We have used the hydrodynamics code LASNEX to model the hydro-expansion of the tantalum target for the ETA-II experiment. The electron beam has kinetic energy of 6 MeV and has a total energy ranges from 720 to 1440 J. The electron beam profile resembles that of a Bennett pinch. The radius for the full-width-at-half-maximum ranges from 1 to 3 mm. For all these parameters, simulations show that the electron beam is able to ablate the central portion of the target. The expansion velocity of the target ranges from about 104 to 5 x 105 cm/s. The target is hot enough so that the surrounding low-density air is ionized and is expanding at a considerably higher velocity than the target itself. Therefore, care must be taken during the experiment to ensure that the measurement is for the tantalum and not for the ionized air.

  5. Pulsed Bessel-Gauss beams: a depleted wave model for type II second-harmonic generation.

    PubMed

    Sabaeian, Mohammad; Motazedian, Alireza; Mohammad Rezaee, Mostafa; Jalil-Abadi, Fatemeh Sedaghat

    2014-11-10

    In this work, a three-dimensional and time-dependent nonlinear wave model to describe the generation of pulsed Bessel-Gauss second-harmonic waves (SHWs) is presented. Three coupled equations, two for ordinary and extraordinary fundamental waves and one for extraordinary SHWs, describing type II second-harmonic generation (SHG) in a KTiOPO4 (KTP) crystal were solved by considering the depletion of fundamental waves (FWs). The results examined the validity of nondepleted wave approximation against the energy of pulses, beam spot size, and interaction length. It was shown that for pulses with spot sizes of ωf=80  μm and energy of 0.8j, the nonlinear interaction was accomplished over a distance of ∼5  mm. Therefore, for KTP crystals with lengths longer than 5 mm, the nondepleted wave approximation can no longer be valid. To be valid, the crystal must be shorter than the interaction length, i.e., 5 mm.

  6. Human mast cells decrease SLPI levels in type II – like alveolar cell model, in vitro

    PubMed Central

    Hollander, Camilla; Nyström, Max; Janciauskiene, Sabina; Westin, Ulla

    2003-01-01

    Background Mast cells are known to accumulate at sites of inflammation and upon activation to release their granule content, e.g. histamine, cytokines and proteases. The secretory leukocyte protease inhibitor (SLPI) is produced in the respiratory mucous and plays a role in regulating the activity of the proteases. Result We have used the HMC-1 cell line as a model for human mast cells to investigate their effect on SLPI expression and its levels in cell co-culture experiments, in vitro. In comparison with controls, we found a significant reduction in SLPI levels (by 2.35-fold, p < 0.01) in a SLPI-producing, type II-like alveolar cell line, (A549) when co-cultured with HMC-1 cells, but not in an HMC-1-conditioned medium, for 96 hours. By contrast, increased SLPI mRNA expression (by 1.58-fold, p < 0.05) was found under the same experimental conditions. Immunohistochemical analysis revealed mast cell transmigration in co-culture with SLPI-producing A549 cells for 72 and 96 hours. Conclusion These results indicate that SLPI-producing cells may assist mast cell migration and that the regulation of SLPI release and/or consumption by mast cells requires interaction between these cell types. Therefore, a "local relationship" between mast cells and airway epithelial cells might be an important step in the inflammatory response. PMID:12952550

  7. Search for non-standard model signatures in the WZ/ZZ final state at CDF run II

    SciTech Connect

    Norman, Matthew

    2009-01-01

    This thesis discusses a search for non-Standard Model physics in heavy diboson production in the dilepton-dijet final state, using 1.9 fb -1 of data from the CDF Run II detector. New limits are set on the anomalous coupling parameters for ZZ and WZ production based on limiting the production cross-section at high š. Additionally limits are set on the direct decay of new physics to ZZ andWZ diboson pairs. The nature and parameters of the CDF Run II detector are discussed, as are the influences that it has on the methods of our analysis.

  8. Modeling Pb (II) adsorption from aqueous solution by ostrich bone ash using adaptive neural-based fuzzy inference system.

    PubMed

    Amiri, Mohammad J; Abedi-Koupai, Jahangir; Eslamian, Sayed S; Mousavi, Sayed F; Hasheminejad, Hasti

    2013-01-01

    To evaluate the performance of Adaptive Neural-Based Fuzzy Inference System (ANFIS) model in estimating the efficiency of Pb (II) ions removal from aqueous solution by ostrich bone ash, a batch experiment was conducted. Five operational parameters including adsorbent dosage (C(s)), initial concentration of Pb (II) ions (C(o)), initial pH, temperature (T) and contact time (t) were taken as the input data and the adsorption efficiency (AE) of bone ash as the output. Based on the 31 different structures, 5 ANFIS models were tested against the measured adsorption efficiency to assess the accuracy of each model. The results showed that ANFIS5, which used all input parameters, was the most accurate (RMSE = 2.65 and R(2) = 0.95) and ANFIS1, which used only the contact time input, was the worst (RMSE = 14.56 and R(2) = 0.46). In ranking the models, ANFIS4, ANFIS3 and ANFIS2 ranked second, third and fourth, respectively. The sensitivity analysis revealed that the estimated AE is more sensitive to the contact time, followed by pH, initial concentration of Pb (II) ions, adsorbent dosage, and temperature. The results showed that all ANFIS models overestimated the AE. In general, this study confirmed the capabilities of ANFIS model as an effective tool for estimation of AE.

  9. Bond-valence model for metal cluster compounds. II. Matrix effect.

    PubMed

    Levi, Elena; Aurbach, Doron; Isnard, Olivier

    2013-10-01

    The bond-valence model was commonly considered as inappropriate to metal cluster compounds, but recently it was shown that the model provides unique information on the lattice strains and stabilization mechanisms in (TM)6-chalcohalides, Mx(TM)6Ly (TM = transition metal, L = the chalcogen and/or halogen ligands; M = counter-cation). The previous study was mainly devoted to the non-uniform distribution of the anion valences (bond-valence sums) around clusters. This and the previous paper are focused on two additional phenomena: (i) a steric conflict between counter-cations and the cluster-ligand framework resulting in `common' lattice strains [previous paper: Levi et al. (2013). Acta Cryst. B69, 419-425], and (ii) steric conflict between the small (TM)6-cluster and the large coordination polyhedron around the cluster or so-called matrix effect (this paper). It was shown that both phenomena can be well described by changes in the bond-valence parameters. This paper demonstrates that the matrix effect results in high strains in the TM-L bonds in most of the (TM)6-chalcohalides (TM = Nb, Mo, W and Re). In spite of this, the violations for the total TM valence are minimal, because the cluster stretching is fully or partially compensated by compression of the TM-L bonds. As a result, the influence of the matrix effect on the material stability is rather positive: it decreases the volume of the structural units and in many cases ensures a more favorable distribution of the bond valences around TM atoms, stabilizing the cluster compound.

  10. Validated competing event model for the stage I-II endometrial cancer population.

    PubMed

    Carmona, Ruben; Gulaya, Sachin; Murphy, James D; Rose, Brent S; Wu, John; Noticewala, Sonal; McHale, Michael T; Yashar, Catheryn M; Vaida, Florin; Mell, Loren K

    2014-07-15

    Early-stage endometrial cancer patients are at higher risk of noncancer mortality than of cancer mortality. Competing event models incorporating comorbidity could help identify women most likely to benefit from treatment intensification. 67,397 women with stage I-II endometrioid adenocarcinoma after total hysterectomy diagnosed from 1988 to 2009 were identified in Surveillance, Epidemiology, and End Results (SEER) and linked SEER-Medicare databases. Using demographic and clinical information, including comorbidity, we sought to develop and validate a risk score to predict the incidence of competing mortality. In the validation cohort, increasing competing mortality risk score was associated with increased risk of noncancer mortality (subdistribution hazard ratio [SDHR], 1.92; 95% confidence interval [CI], 1.60-2.30) and decreased risk of endometrial cancer mortality (SDHR, 0.61; 95% CI, 0.55-0.78). Controlling for other variables, Charlson Comorbidity Index (CCI) = 1 (SDHR, 1.62; 95% CI, 1.45-1.82) and CCI >1 (SDHR, 3.31; 95% CI, 2.74-4.01) were associated with increased risk of noncancer mortality. The 10-year cumulative incidences of competing mortality within low-, medium-, and high-risk strata were 27.3% (95% CI, 25.2%-29.4%), 34.6% (95% CI, 32.5%-36.7%), and 50.3% (95% CI, 48.2%-52.6%), respectively. With increasing competing mortality risk score, we observed a significant decline in omega (ω), indicating a diminishing likelihood of benefit from treatment intensification. Comorbidity and other factors influence the risk of competing mortality among patients with early-stage endometrial cancer. Competing event models could improve our ability to identify patients likely to benefit from treatment intensification. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Validated Competing Event Model for the Stage I-II Endometrial Cancer Population

    SciTech Connect

    Carmona, Ruben; Gulaya, Sachin; Murphy, James D.; Rose, Brent S.; Wu, John; Noticewala, Sonal; McHale, Michael T.; Yashar, Catheryn M.; Vaida, Florin; Mell, Loren K.

    2014-07-15

    Purpose/Objectives(s): Early-stage endometrial cancer patients are at higher risk of noncancer mortality than of cancer mortality. Competing event models incorporating comorbidity could help identify women most likely to benefit from treatment intensification. Methods and Materials: 67,397 women with stage I-II endometrioid adenocarcinoma after total hysterectomy diagnosed from 1988 to 2009 were identified in Surveillance, Epidemiology, and End Results (SEER) and linked SEER-Medicare databases. Using demographic and clinical information, including comorbidity, we sought to develop and validate a risk score to predict the incidence of competing mortality. Results: In the validation cohort, increasing competing mortality risk score was associated with increased risk of noncancer mortality (subdistribution hazard ratio [SDHR], 1.92; 95% confidence interval [CI], 1.60-2.30) and decreased risk of endometrial cancer mortality (SDHR, 0.61; 95% CI, 0.55-0.78). Controlling for other variables, Charlson Comorbidity Index (CCI) = 1 (SDHR, 1.62; 95% CI, 1.45-1.82) and CCI >1 (SDHR, 3.31; 95% CI, 2.74-4.01) were associated with increased risk of noncancer mortality. The 10-year cumulative incidences of competing mortality within low-, medium-, and high-risk strata were 27.3% (95% CI, 25.2%-29.4%), 34.6% (95% CI, 32.5%-36.7%), and 50.3% (95% CI, 48.2%-52.6%), respectively. With increasing competing mortality risk score, we observed a significant decline in omega (ω), indicating a diminishing likelihood of benefit from treatment intensification. Conclusion: Comorbidity and other factors influence the risk of competing mortality among patients with early-stage endometrial cancer. Competing event models could improve our ability to identify patients likely to benefit from treatment intensification.

  12. Equilibrium and kinetic modelling of Cd(II) biosorption by algae Gelidium and agar extraction algal waste.

    PubMed

    Vilar, Vítor J P; Botelho, Cidália M S; Boaventura, Rui A R

    2006-01-01

    In this study an industrial algal waste from agar extraction has been used as an inexpensive and effective biosorbent for cadmium (II) removal from aqueous solutions. This biosorbent was compared with the algae Gelidium itself, which is the raw material for agar extraction. Equilibrium data follow both Langmuir and Redlich-Peterson models. The parameters of Langmuir equilibrium model are q(max)=18.0 mgg(-1), b=0.19 mgl(-1) and q(max)=9.7 mgg(-1), b=0.16 mgl(-1), respectively for Gelidium and the algal waste. Kinetic experiments were conducted at initial Cd(II) concentrations in the range 6-91 mgl(-1). Data were fitted to pseudo-first- and second-order Lagergren models. For an initial Cd(II) concentration of 91 mgl(-1) the parameters of the pseudo-first-order Lagergren model are k(1,ads)=0.17 and 0.87 min(-1); q(eq)=16.3 and 8.7 mgg(-1), respectively, for Gelidium and algal waste. Kinetic constants vary with the initial metal concentration. The adsorptive behaviour of biosorbent particles was modelled using a batch reactor mass transfer kinetic model. The model successfully predicts Cd(II) concentration profiles and provides significant insights on the biosorbents performance. The homogeneous diffusivity, D(h), is in the range 0.5-2.2 x10(-8) and 2.1-10.4 x10(-8)cm(2)s(-1), respectively, for Gelidium and algal waste.

  13. Integrated structural model and membrane targeting mechanism of the human ESCRT-II complex

    SciTech Connect

    Im, Young Jun; Hurley, James H.

    2009-01-15

    ESCRT-II plays a pivotal role in receptor downregulation and multivesicular body biogenesis and is conserved from yeast to humans. The crystal structures of two human ESCRT-II complex structures have been determined at 2.6 and 2.9 {angstrom} resolution, respectively. The complex has three lobes and contains one copy each of VPS22 and VPS36 and two copies of VPS25. The structure reveals a dynamic helical domain to which both the VPS22 and VPS36 subunits contribute that connects the GLUE domain to the rest of the ESCRT-II core. Hydrodynamic analysis shows that intact ESCRT-II has a compact, closed conformation. ESCRT-II binds to the ESCRT-I VPS28 C-terminal domain subunit through a helix immediately C-terminal to the VPS36-GLUE domain. ESCRT-II is targeted to endosomal membranes by the lipid-binding activities of both the Vps36 GLUE domain and the first helix of Vps22. These data provide a unifying structural and functional framework for the ESCRT-II complex.

  14. Integrated structural model and membrane targeting mechanism of the human ESCRT-II complex

    PubMed Central

    Im, Young Jun; Hurley, James H.

    2008-01-01

    Summary ESCRT-II plays a pivotal role in receptor downregulation and multivesicular body biogenesis, and is conserved from yeast to humans. The crystal structures of two human ESCRT-II complex structures have been determined at 2.6 and 2.9 Å resolution, respectively. The complex has three lobes and contains one copy each of VPS22 and VPS36, and two copies of VPS25. The structure reveals a dynamic helical domain to which both the VPS22 and VPS36 subunits contribute, which connects the GLUE domain to the rest of the ESCRT-II core. Hydrodynamic analysis shows that intact ESCRT-II has a compact, closed conformation. ESCRT-II binds to the ESCRT-I VPS28 C-terminal domain subunit through a helix immediately C-terminal to the VPS36-GLUE domain. ESCRT-II is targeted to endosomal membranes by the lipid binding activities of both the Vps36 GLUE domain and the first helix of Vps22. These data provide a unifying structural and functional framework for the ESCRT-II complex. PMID:18539118

  15. New LUX and PandaX-II results illuminating the simplest Higgs-portal dark matter models

    NASA Astrophysics Data System (ADS)

    He, Xiao-Gang; Tandean, Jusak

    2016-12-01

    Direct searches for dark matter (DM) by the LUX and PandaX-II Collaborations employing xenon-based detectors have recently come up with the most stringent limits to date on the spin-independent elastic scattering of DM off nucleons. For Higgs-portal scalar DM models, the new results have precluded any possibility of accommodating low-mass DM as suggested by the DAMA and CDMS II Si experiments utilizing other target materials, even after invoking isospin-violating DM interactions with nucleons. In the simplest model, SM+D, which is the standard model plus a real singlet scalar named darkon acting as the DM candidate, the LUX and PandaX-II limits rule out DM masses roughly from 4 to 450 GeV, except a small range around the resonance point at half of the Higgs mass where the interaction cross-section is near the neutrino-background floor. In the THDM II+D, which is the type-II two-Higgs-doublet model combined with a darkon, the region excluded in the SM+D by the direct searches can be recovered due to suppression of the DM effective interactions with nucleons at some values of the ratios of Higgs couplings to the up and down quarks, making the interactions significantly isospin-violating. However, in either model, if the 125-GeV Higgs boson is the portal between the dark and SM sectors, DM masses less than 50 GeV or so are already ruled out by the LHC constraint on the Higgs invisible decay. In the THDM II+D, if the heavier CP -even Higgs boson is the portal, theoretical restrictions from perturbativity, vacuum stability, and unitarity requirements turn out to be important instead and exclude much of the region below 100 GeV. For larger DM masses, the THDM II+D has plentiful parameter space that corresponds to interaction cross-sections under the neutrino-background floor and therefore is likely to be beyond the reach of future direct searches without directional sensitivity.

  16. Heterogeneous Concurrent Modeling and Design in Java (Volume 2: Ptolemy II Software Architecture)

    DTIC Science & Technology

    2008-04-01

    than one port. R3 E4 P5 E0 E2 P2 P4R2 P3 E3 P1 E1 R1 14 Ptolemy II The Kernel of each of P2 and P4, in addition to its link to the outside of P3. Thus...Ptolemy II The Kernel 1.6.1 Limitations of Monitors Java threads provide a low -level mechanism called a monitor for controlling concurrent access to...constraint in Ptolemy II on the number of workspaces used, so sub- classes of these kernel classes could judiciously use additional workspaces to increase

  17. A two-dimensional model study of the QBO signal in SAGE II NO2 and O3

    NASA Technical Reports Server (NTRS)

    Chipperfield, M. P.; Gray, L. J.; Kinnersley, J. S.; Zawodny, J.

    1994-01-01

    Calculations of the quasi biennial oscillation (QBO) signal in Stratospheric Aerosol and Gas Experiment (SAGE) II O3 and NO2 data between 1984 and 1991 are presented and have been investigated by using a two-dimensional model. The isentropic 2D model is a fully interactive radiative-dynamical-chemical model in which the eddy fluxes of chemical species are calculated in a consistent manner. The QBO in the model has been forced by relaxing the equatorial zonal wind toward the observations at Singapore allowing the comparison of the model with observations from specific years. The model reproduces the observed vertical structure of the equatorial ozone anomaly with the well-known transition from dynamical to photochemical control at around 28km. The model also reproduces the observed vertical structure of the SAGE II observed NO2 anomaly. The model studies have shown that it is the QBO modulation of NO2 which the main cause of QBO signal in O3 above 30 km. The model also reproduces the observed latitudinal structure of the QBO signals in O3 and NO2. Due to the differing horizontal distribution of O3 and NO(y) the ozone signal shows a distinct phase change in the subtropics whereas the NO2 anomaly gives a broader signal.

  18. A two-dimensional model study of the QBO signal in SAGE II NO2 and O3

    NASA Technical Reports Server (NTRS)

    Chipperfield, M. P.; Gray, L. J.; Kinnersley, J. S.; Zawodny, J.

    1994-01-01

    Calculations of the quasi biennial oscillation (QBO) signal in Stratospheric Aerosol and Gas Experiment (SAGE) II O3 and NO2 data between 1984 and 1991 are presented and have been investigated by using a two-dimensional model. The isentropic 2D model is a fully interactive radiative-dynamical-chemical model in which the eddy fluxes of chemical species are calculated in a consistent manner. The QBO in the model has been forced by relaxing the equatorial zonal wind toward the observations at Singapore allowing the comparison of the model with observations from specific years. The model reproduces the observed vertical structure of the equatorial ozone anomaly with the well-known transition from dynamical to photochemical control at around 28km. The model also reproduces the observed vertical structure of the SAGE II observed NO2 anomaly. The model studies have shown that it is the QBO modulation of NO2 which the main cause of QBO signal in O3 above 30 km. The model also reproduces the observed latitudinal structure of the QBO signals in O3 and NO2. Due to the differing horizontal distribution of O3 and NO(y) the ozone signal shows a distinct phase change in the subtropics whereas the NO2 anomaly gives a broader signal.

  19. The Chemical Properties of Milky Way and M31 Globular Clusters. II. Stellar Population Model Predictions

    NASA Astrophysics Data System (ADS)

    Beasley, Michael A.; Brodie, Jean P.; Strader, Jay; Forbes, Duncan A.; Proctor, Robert N.; Barmby, Pauline; Huchra, John P.

    2005-03-01

    We derive ages, metallicities, and abundance ratios ([α/Fe]) from the integrated spectra of 23 globular clusters in M31 by employing multivariate fits to two different stellar population models. We also perform a parallel analysis on 21 Galactic globular clusters as a consistency check and in order to facilitate a differential analysis. Our analysis shows that the M31 globular clusters separate into three distinct components in age and metallicity; we identify an old, metal-poor group (seven clusters), an old, metal-rich group (10 clusters), and an intermediate-age (3-6 Gyr), intermediate-metallicity ([Z/H]~-1) group (six clusters). This third group is not identified in the Galactic globular cluster sample. We also see evidence that the old, metal-rich Galactic globular clusters are 1-2 Gyr older than their counterparts in M31. The majority of globular clusters in both samples appear to be enhanced in α-elements, but the degree of enhancement is rather model-dependent. The intermediate-age globular clusters appear to be the most enhanced, with [α/Fe]~0.4. These clusters are clearly depressed in CN with respect to the models and the bulk of the M31 and Milky Way sample. Compared with the bulge of M31, M32, and NGC 205, these clusters most resemble the stellar populations in NGC 205 in terms of age, metallicity, and CN abundance. We infer horizontal branch morphologies for the M31 clusters using the Rose Ca II index and demonstrate that blue horizontal branches are not leading to erroneous age estimates in our analysis. We discuss and reject as unlikely the hypothesis that these objects are in fact foreground stars contaminating the optical catalogs. The intermediate-age clusters have generally higher velocities than the bulk of the M31 cluster population. Spatially, three of these clusters are projected onto the bulge region, and the remaining three are distributed at large radii. We discuss these objects within the context of the build-up of the M31 halo and

  20. Coordination mode of pentadentate ligand derivative of 5-amino-1,3,4-thiadiazole-2-thiol with nickel(II) and copper(II) metal ions: synthesis, spectroscopic characterization, molecular modeling and fungicidal study.

    PubMed

    Chandra, Sulekh; Gautam, Seema; Kumar, Amit; Madan, Molly

    2015-02-05

    Complexes of nickel(II), and copper(II) were synthesized with pantadentate ligand i.e. 3,3'-thiodipropionicacid-bis(5-amino-1,3,4-thiadiazole-2-thiol) (L). The ligand was synthesized by the condensation of thiodipropionic acid and 5-amino-1,3,4-thiadiazole-2-thiol in 1:2 ratio, respectively. Synthesized ligand was characterized by elemental analysis, mass, (1)H NMR, IR, and molecular modeling. All the complexes were characterized by elemental analysis, molar conductance, magnetic moment, IR, electronic spectra, ESR, and molecular modeling. The newly synthesized complexes possessed general composition [M(L)X2] where M = Ni(II), Cu(II), L = pantadentate ligand and X = Cl(-), CH3COO(-). The IR spectral data indicated that the ligand behaved as a pantadentate ligand and coordinated to the metal ion through N2S3 donor atoms. The molar conductance value of Ni(II), and Cu(II) complexes in DMSO corresponded to their electrolytic behavior. On the basis of spectral study, octahedral and tetragonal geometry was assigned for Ni(II) and Cu(II) complexes, respectively. In vitro fungicidal study of ligand and its complexes was investigated against fungi Candida albicans, Candida parapsilosis, Candidia krusei, and Candida tropicalis by means of well diffusion method.

  1. Coordination mode of pentadentate ligand derivative of 5-amino-1,3,4-thiadiazole-2-thiol with nickel(II) and copper(II) metal ions: Synthesis, spectroscopic characterization, molecular modeling and fungicidal study

    NASA Astrophysics Data System (ADS)

    Chandra, Sulekh; Gautam, Seema; Kumar, Amit; Madan, Molly

    2015-02-01

    Complexes of nickel(II), and copper(II) were synthesized with pantadentate ligand i.e. 3,3‧-thiodipropionicacid-bis(5-amino-1,3,4-thiadiazole-2-thiol) (L). The ligand was synthesized by the condensation of thiodipropionic acid and 5-amino-1,3,4-thiadiazole-2-thiol in 1:2 ratio, respectively. Synthesized ligand was characterized by elemental analysis, mass, 1H NMR, IR, and molecular modeling. All the complexes were characterized by elemental analysis, molar conductance, magnetic moment, IR, electronic spectra, ESR, and molecular modeling. The newly synthesized complexes possessed general composition [M(L)X2] where M = Ni(II), Cu(II), L = pantadentate ligand and X = Cl-, CH3COO-. The IR spectral data indicated that the ligand behaved as a pantadentate ligand and coordinated to the metal ion through N2S3 donor atoms. The molar conductance value of Ni(II), and Cu(II) complexes in DMSO corresponded to their electrolytic behavior. On the basis of spectral study, octahedral and tetragonal geometry was assigned for Ni(II) and Cu(II) complexes, respectively. In vitro fungicidal study of ligand and its complexes was investigated against fungi Candida albicans, Candida parapsilosis, Candidia krusei, and Candida tropicalis by means of well diffusion method.

  2. Raman Scattered He II 4332 and Photoionization Model in the Symbiotic Star V1016 Cygni

    NASA Astrophysics Data System (ADS)

    Lee, H.-W.; Heo, J.-E.; Lee, B.-C.

    2014-08-01

    Symbiotic stars are wide binary systems of a white dwarf and a mass losing giant. They exhibit unique Raman scattered features as a result of inelastic scattering of far UV line photons by atomic hydrogen. Co-existence of a far UV He II emission region and a thick H I region in symbiotic stars is necessary for the formation of Raman-scattered features blueward of hydrogen Balmer emission lines. Being a single electron atom, He II has the same atomic structure as the hydrogen atom and hence emits far UV emission lines that are slightly blueward of hydrogen Lyman lines. These far UV He II emission lines can be Raman scattered to appear blueward of hydrogen Balmer lines. In particular, the symbiotic star V1016 Cyg is found to exhibit Raman scattered He II 4332 feature in the BOES high resolution spectrum. Our profile fitting of Raman scattered He II 4332 is consistent with the mass loss geometry proposed by Jung & Lee (2004). We use the photoionization code ‘ CLOUDY' to estimate the far UV He II emission lines and make comparisons with the observed Raman scattered He II 4332 blueward of Hγ in the high resolution echelle V1016 Cyg. The emission nebula is assumed to be of uniform density of 108 cm-3 that is illuminated by a black body characterized by its temperature and total luminosity. With our comparisons we conclude that the Raman scattered He II features are consistent with the existence of a photoionized nebula by a hot black body source with temperature 7-8× 104 K with a luminosity 1038erg s-1.

  3. Mixed ligand Cu(II)N2O2 complexes: biomimetic synthesis, activities in vitro and biological models, theoretical calculations.

    PubMed

    Li, Chen; Yin, Bing; Kang, Yifan; Liu, Ping; Chen, Liang; Wang, Yaoyu; Li, Jianli

    2014-12-15

    Three new mixed ligand Cu(II)N2O2 complexes, namely, [Cu(II)(2-A-6-MBT)2(m-NB)2] (1), [Cu(II)(2-ABT)2(m-NB)2] (2), and [Cu(II)(2-ABT)2(o-NB)2] (3), (2-A-6-MBT = 2-amino-6-methoxybenzothiazole, m-NB = m-nitrobenzoate, 2-ABT = 2-aminobenzothiazole, and o-NB = o-nitrobenzoate), have been prepared by the biomimetic synthesis strategy, and their structures were determined by X-ray crystallography studies and spectral methods. These complexes exhibited the effective superoxide dismutase (SOD) activity and catecholase activity. On the basis of the experimental data and computational studies, the structure-activity relationship for these complexes was investigated. The results reveal that electron-accepting abilities of these complexes and coordination geometries have significant effects on the SOD activity and catecholase activity. Then, we found that 1 and 2 exerted potent intracellular antioxidant capacity in the model of H2O2-induced oxidative stress based on HeLa cervical cancer cells, which were screened out by the cytotoxicity assays of different kinds of cells. Furthermore, 1-3 showed the favorable biocompatibility in two different biological models: Saccharomyces cerevisiae and human vascular endothelial cells. These biological experimental data are indicative of the promising application potential of these complexes in biology and pharmacology.

  4. CENTAR modelling of the TOPAZ-II: Loss of vacuum chamber cooling during full power ground test

    NASA Astrophysics Data System (ADS)

    Standley, Vaughn H.; Morris, D. Brent; Schuller, Michael J.

    1992-01-01

    The Code for Extended Non-linear Transient Analysis of Extraterrestrial Reactors (CENTAR) was used to model an electrically heated TOPAZ-II thermionic space reactor operating at full power following a loss of coolant to its enclosing vacuum chamber. The purpose of the work was to quantity the response time available to Thermionic System Evaluation Test (TSET) operators following an interruption of vacuum chamber cooling and to test the utility of the CENTAR code for modelling a true-to-life application. A parametric study was done to test key assumptions and to refine the TOPAZ-II input deck being used. The vacuum chamber temperature history was then solved for under the assumption that full power would be maintained (at 115 kWth) during the loss of vacuum chamber cooling. The vacuum chamber temperatures were substituted into the CENTAR input deck for the space temperature variable. Each space temperature was associated with a point in time to simulate transient conditions in the electric heaters, thermionic elements, liquid metal coolant, and radiator. It was verified that the TOPAZ-II equilibrated fast enough such that CENTAR could run in steady state mode to generate a quasi-transient solution. Results indicated that TSET operators would have several minutes to regain total or partial cooling and that drastic action (emergency shutdown of the TOPAZ-II electric heater power, for example) would not be required.

  5. Ultraviolet C II and Si III Transit Spectroscopy and Modeling of the Evaporating Atmosphere of GJ436b

    NASA Astrophysics Data System (ADS)

    Parke Loyd, R. O.; Koskinen, T. T.; France, Kevin; Schneider, Christian; Redfield, Seth

    2017-01-01

    Hydrogen gas evaporating from the atmosphere of the hot-Neptune GJ436b absorbs over 50% of the stellar Lyα emission during transit. Given the planet’s atmospheric composition and energy-limited escape rate, this hydrogen outflow is expected to entrain heavier atoms such as C and O. We searched for C and Si in the escaping atmosphere of GJ436b using far-ultraviolet Hubble Space Telescope COS G130M observations made during the planet’s extended H i transit. These observations show no transit absorption in the C ii 1334,1335 Å and Si iii 1206 Å lines integrated over [-100, 100] km s-1, imposing 95% (2σ) upper limits of 14% (C ii) and 60% (Si iii) depth on the transit of an opaque disk and 22% (C ii) and 49% (Si iii) depth on an extended highly asymmetric transit similar to that of H i Lyα. C+ is likely present in the outflow according to a simulation we carried out using a spherically symmetric photochemical-hydrodynamical model. This simulation predicts an ˜2% transit over the integrated bandpass, consistent with the data. At line center, we predict the C ii transit depth to be as high as 19%. Our model predicts a neutral hydrogen escape rate of 1.6× {10}9 g s-1 (3.1× {10}9 g s-1 for all species) for an upper atmosphere composed of hydrogen and helium.

  6. Final Report: Phase II Nevada Water Resources Data, Modeling, and Visualization (DMV) Center

    SciTech Connect

    Jackman, Thomas; Minor, Timothy; Pohll, Gregory

    2013-07-22

    Water is unquestionably a critical resource throughout the United States. In the semi-arid west -- an area stressed by increase in human population and sprawl of the built environment -- water is the most important limiting resource. Crucially, science must understand factors that affect availability and distribution of water. To sustain growing consumptive demand, science needs to translate understanding into reliable and robust predictions of availability under weather conditions that could be average but might be extreme. These predictions are needed to support current and long-term planning. Similar to the role of weather forecast and climate prediction, water prediction over short and long temporal scales can contribute to resource strategy, governmental policy and municipal infrastructure decisions, which are arguably tied to the natural variability and unnatural change to climate. Change in seasonal and annual temperature, precipitation, snowmelt, and runoff affect the distribution of water over large temporal and spatial scales, which impact the risk of flooding and the groundwater recharge. Anthropogenic influences and impacts increase the complexity and urgency of the challenge. The goal of this project has been to develop a decision support framework of data acquisition, digital modeling, and 3D visualization. This integrated framework consists of tools for compiling, discovering and projecting our understanding of processes that control the availability and distribution of water. The framework is intended to support the analysis of the complex interactions between processes that affect water supply, from controlled availability to either scarcity or deluge. The developed framework enables DRI to promote excellence in water resource management, particularly within the Lake Tahoe basin. In principle, this framework could be replicated for other watersheds throughout the United States. Phase II of this project builds upon the research conducted during

  7. Plumes and Blooms: Modeling the Case II Waters of the Santa Barbara Channel. Chapter 15

    NASA Technical Reports Server (NTRS)

    Siegel, D. A.; Maritorena, S.; Nelson, N. B.

    2003-01-01

    The goal of the Plumes and Blooms (PnB) project is to develop, validate and apply to imagery state-of-the-art ocean color algorithms for quantifying sediment plumes and phytoplankton blooms for the Case II environment of the Santa Barbara Channel. We conduct monthly to twice-monthly transect observations across the Santa Barbara Channel to develop an algorithm development and product validation data set. The PnB field program started in the summer of 1996. At each of the 7 PnB stations, a complete verification bio-geo-optical data set is collected. Included are redundant measures of apparent optical properties (remote sensing reflectance and diffuse attenuation spectra), as well as in situ profiles of spectral absorption, beam attenuation and backscattering coefficients. Water samples are analyzed for component in vivo absorption spectra, fluorometric chlorophyll, phytoplankton pigment (by the SDSU CHORS laboratory), and inorganic nutrient concentrations. A primary goal is to use the PnB field data set to objectively tune semi-analytical models of ocean color for this site and apply them using available satellite imagery (SeaWiFS and MODIS). In support of this goal, we have also been addressing SeaWiFS ocean color and AVHRR SST imagery. We also are using the PnB data set to address time/space variability of water masses in the Santa Barbara Channel and its relationship to the 1997/1998 El Nino. However, the comparison between PnB field observations and satellite estimates of primary products has been disappointing. We find that field estimates of water-leaving radiance, L(sub wN)(lambda), correspond poorly to satellite estimates for both SeaWiFS and MODIS local area coverage imagery. We believe this is due to poor atmospheric correction due to complex mixtures of aerosol types found in these near-coastal regions. Last, we remain active in outreach activities.

  8. Modelling the chemistry of star-forming filaments - II. Testing filament characteristics with synthetic observations

    NASA Astrophysics Data System (ADS)

    Seifried, D.; Sánchez-Monge, Á.; Suri, S.; Walch, S.

    2017-06-01

    We present synthetic continuum and 13CO and C18O line emission observations of dense and cold filaments. The filaments are dynamically evolved using 3D-magnetohydrodynamic simulations that include one of the largest on-the-fly chemical networks used to date, which models the detailed evolution of H2 and CO. We investigate the reliability of observable properties, in particular filament mass and width, under different simulation conditions like magnetic field orientation and cosmic ray ionization rate. We find that filament widths of ˜0.1 pc can be probed with both line and continuum emission observations with a high accuracy (deviations ≤20 per cent). However, the width of more narrow filaments can be significantly overestimated by up to a factor of a few. Masses obtained via the dust emission are accurate within a few per cent whereas the masses inferred from molecular line emission observations deviate from the actual mass by up to a factor of 10 and show large differences for different J transitions. The inaccurate estimate of filament masses and widths of narrow filaments using molecular line observations can be attributed to (i) the non-isothermal state of the filaments, (ii) optical depth effects and (iii) the subthermally excited state of CO, while inclination effects and opacity correction only influence the obtained masses and widths by less than 50 per cent. Both, mass and width estimates, can be improved by using two isotopes to correct for the optical depth. Since gas and dust temperatures generally differ (by up to 25 K), the filaments appear more gravitationally unstable if the (too low) dust temperature is used for the stability analysis.

  9. Hydrolysis of a Model for the 5'-Cap of mRNA by Dinuclear Copper(II) and Zinc(II) Complexes. Rapid Hydrolysis by Four Copper(II) Ions.

    PubMed

    McCue, Kevin P.; Morrow, Janet R.

    1999-12-27

    Two bis(triazacyclononane) ligands, 1,3-bis(1,4,7-triaza-1-cyclononyl)-p-xylene (pXTD) and 1,3-bis(1,4,7-triaza-1-cyclononyl)-m-xylene (mXTD), form stable dinuclear Cu(II) complexes (Cu(2)L). At pH 7.3, the predominant species are bis(hydroxide) complexes (Cu(2)L(OH)(2)(2+)) as determined by equilibrium modeling of pH-potentiometric measurements. Several dinuclear and mononuclear Cu(II) complexes and a dinuclear Zn(II) complex promote the hydrolysis of GpppG, a model for the 5'-cap of mRNA. At 0.125 mM complex, both Cu(2)(pXTD) and Cu(2)(mXTD) promote hydrolysis of GpppG approximately 100-fold more rapidly than does the monomeric Cu(TACN) complex (0.250 mM) at pH 7.3 and 37 degrees C (TACN = 1,4,7-triazacyclononane). The dependence of the rate constant on dinuclear Cu(II) complex concentration suggests that Cu(2)(pXTD) promotes hydrolysis through both a 1:1 complex (Cu(2)L-GpppG) and a 2:1 complex ((Cu(2)L)(2)-GpppG). The 2:1 complex is 20-fold more reactive than the 1:1 complex; a first-order rate constant of 1.1 x 10(-)(4) s(-)(1) is determined for hydrolysis of the 2:1 complex. Cu(2)(mXTD) effectively promotes the hydrolysis of GpppG only through a 2:1 complex which hydrolyzes with a first-order rate constant of 4.3 x 10 (-)(5) s(-)(1). Cu(2)(pXTD) binds as a 1:1 complex to m(7)GpppG with a binding constant of 27 000 M(-)(1) as determined by use of fluorescence spectroscopy. Two Cu(2)(mXTD) complexes bind stepwise to m(7)GpppG with binding constants of 5300 and 12 000 M(-)(1) for the first complex and second complex, respectively.

  10. A model of nitrous oxide evolution from soil driven by rainfall events. I - Model structure and sensitivity. II - Model applications

    NASA Technical Reports Server (NTRS)

    Changsheng, LI; Frolking, Steve; Frolking, Tod A.

    1992-01-01

    Simulations of N2O and CO2 emissions from soils were conducted with a rain-event driven, process-oriented model (DNDC) of nitrogen and carbon cycling processes in soils. The magnitude and trends of simulated N2O (or N2O + N2) and CO2 emissions were consistent with the results obtained in field experiments. The successful simulation of these emissions from the range of soil types examined demonstrates that the DNDC will be a useful tool for the study of linkages among climate, soil-atmosphere interactions, land use, and trace gas fluxes.

  11. An exploratory study of proficient undergraduate Chemistry II students' application of Lewis's model

    NASA Astrophysics Data System (ADS)

    Lewis, Sumudu R.

    This exploratory study was based on the assumption that proficiency in chemistry must not be determined exclusively on students' declarative and procedural knowledge, but it should be also described as the ability to use variety of reasoning strategies that enrich and diversify procedural methods. The study furthermore assumed that the ability to describe the structure of a molecule using Lewis's model and use it to predict its geometry as well as some of its properties is indicative of proficiency in the essential concepts of covalent bonding and molecule structure. The study therefore inquired into the reasoning methods and procedural techniques of proficient undergraduate Chemistry II students when solving problems, which require them to use Lewis's model. The research design included an original survey, designed by the researcher for this study, and two types of interviews, with students and course instructors. The purpose of the survey was two-fold. First and foremost, the survey provided a base for the student interview selection, and second it served as the foundation for the inquiry into the strategies the student use when solving survey problems. Twenty two students were interviewed over the course of the study. The interview with six instructors allowed to identify expected prior knowledge and skills, which the students should have acquired upon completion of the Chemistry I course. The data, including videos, audios, and photographs of the artifacts produced by students during the interviews, were organized and analyzed manually and using QSR NVivo 10. The research found and described the differences between proficient and non-proficient students' reasoning and procedural strategies when using Lewis's model to describe the structure of a molecule. One of the findings clearly showed that the proficient students used a variety of cues to reason, whereas other students used one memorized cue, or an algorithm, which often led to incorrect representations in

  12. Structure of an Iron(II) Dioxygen Complex; A Model for Oxygen Carrying Hemeproteins

    PubMed Central

    Collman, James P.; Gagne, Robert R.; Reed, Christopher A.; Robinson, Ward T.; Rodley, Gordon A.

    1974-01-01

    The preliminary structural characterization of a reversible ferrous dioxygen complex is reported. Mono(N-methyl imidazole) (dioxygen) meso-tetra (α,α,α,α-o-pivalamidephenyl) porphinatorino(II), [Fe(O2)-(N-Me imid) (α,α,α,α-TpivPP)], 1, isolated from toluene solution, crystallizes in the monoclinic system with four molecules in a unit cell of dimensions a = 18.690 (3), b = 19.514 (3), c = 18.638 (3) Å, and β = 91.00 (1)°. R = 0.15 for 841 reflections having F2 > 3σ (F2). The complex 1 has four pivalamido groups on one side of the porphyrin forming a hydrophobic pocket of 5.4-Å depth which encloses coordinated dioxygen. The dioxygen is coordinated “end-on,” with a bent Fe-O-O bond. The Fe-O-O plane bisects an N-Fe-N right angle of the equatorial iron porphyrin plane and is four way statistically disordered. In addition there is a crystallographic 2-fold axis through iron, coordinated oxygen, and nitrogen of the axially bound N-methyl imidazole. Thus there are two types of coordinated dioxygen with the Fe-O-O plane either parallel or perpendicular to the trans axial imidazole plane. Corresponding values for the Fe-O-O bond angles are 135-(4)° and 137(4)° and for the O-O bond lengths are 1.23 (0.08) and 1.26 (0.08) Å, with a dihedral angle of 90° between alternative orientations of the Fe-O-O plane. The Fe-O distance is 1.75 (0.02) Å and Fe-N (imidazole) is 2.07 (0.02) Å, suggesting multiple bond character in the Fe-O moiety. The similarity of the Mössbauer spectrum of the model complex, 1, with oxyhemoglobin indicates that 1 may be a good model for oxygen binding in the oxygen transport hemeproteins. PMID:4524640

  13. Electronic Structure of a CuII-Alkoxide Complex Modeling Intermediates in Copper-Catalyzed Alcohol Oxidations

    PubMed Central

    Hayes, Ellen C.; Porter, Thomas R.; Barrows, Charles J.; Kaminsky, Werner; Mayer, James M.; Stoll, Stefan

    2016-01-01

    In the copper-catalyzed oxidation of alcohols to aldehydes, a CuII-alkoxide (CuII-OR) intermediate is believed to modulate the αC-H bond strength of the deprotonated substrate to facilitate the oxidation. As a structural model for these intermediates, we characterized the electronic structure of the stable compound TptBuCuII(OCH2CF3) (TptBu = (hydro-tris (3-tert-butyl-pyrazolyl) borate) and investigated the influence of the trifluoroethoxide ligand on the electronic structure of the complex. The compound exhibits an electron paramagnetic resonance (EPR) spectrum with an unusually large gzz value of 2.44 and a small copper hyperfine coupling Azz of 40·10−4 cm−1 (120 MHz). Single-crystal electron nuclear double resonance (ENDOR) spectra show that the unpaired spin population is highly localized on the copper ion (≈ 68 %), with no more than 15 % on the ethoxide oxygen. Electronic absorption and magnetic circular dichroism (MCD) spectra show weak ligand-field transitions between 5000 and 12000 cm−1 and an intense ethoxide-to-copper charge transfer (LMCT) transition at 24000 cm−1, resulting in the red color of this complex. Resonance Raman (rR) spectroscopy reveals a Cu-O stretch mode at 592 cm−1. Quantum chemical calculations support the interpretation and assignment of the experimental data. Compared to known CuII-thiolate and CuII-alkylperoxo complexes from the literature, we found an increased σ interaction in the CuII-OR bond that results in the spectroscopic features. These insights lay the basis for further elucidating the mechanism of copper-catalyzed alcohol oxidations. PMID:26907976

  14. Electronic Structure of a Cu(II)-Alkoxide Complex Modeling Intermediates in Copper-Catalyzed Alcohol Oxidations.

    PubMed

    Hayes, Ellen C; Porter, Thomas R; Barrows, Charles J; Kaminsky, Werner; Mayer, James M; Stoll, Stefan

    2016-03-30

    In the copper-catalyzed oxidation of alcohols to aldehydes, a Cu(II)-alkoxide (Cu(II)-OR) intermediate is believed to modulate the αC-H bond strength of the deprotonated substrate to facilitate the oxidation. As a structural model for these intermediates, we characterized the electronic structure of the stable compound Tp(tBu)Cu(II)(OCH2CF3) (Tp(tBu) = hydro-tris(3-tert-butyl-pyrazolyl)borate) and investigated the influence of the trifluoroethoxide ligand on the electronic structure of the complex. The compound exhibits an electron paramagnetic resonance (EPR) spectrum with an unusually large gzz value of 2.44 and a small copper hyperfine coupling Azz of 40 × 10(-4) cm(-1) (120 MHz). Single-crystal electron nuclear double resonance (ENDOR) spectra show that the unpaired spin population is highly localized on the copper ion (≈68%), with no more than 15% on the ethoxide oxygen. Electronic absorption and magnetic circular dichroism (MCD) spectra show weak ligand-field transitions between 5000 and 12,000 cm(-1) and an intense ethoxide-to-copper charge transfer (LMCT) transition at 24,000 cm(-1), resulting in the red color of this complex. Resonance Raman (rR) spectroscopy reveals a Cu-O stretch mode at 592 cm(-1). Quantum chemical calculations support the interpretation and assignment of the experimental data. Compared to known Cu(II)-thiolate and Cu(II)-alkylperoxo complexes from the literature, we found an increased σ interaction in the Cu(II)-OR bond that results in the spectroscopic features. These insights lay the basis for further elucidating the mechanism of copper-catalyzed alcohol oxidations.

  15. Assessing Inter-Model Continuity Between the Section II and Section III Conceptualizations of Borderline Personality Disorder in DSM-5.

    PubMed

    Evans, Chloe M; Simms, Leonard J

    2017-03-02

    DSM-5 includes 2 competing models of borderline personality disorder (BPD) in Sections II and III. Empirical comparisons between these models are required to understand and improve intermodel continuity. We compared Section III BPD traits to Section II BPD criteria assessed via semistructured interviews in 455 current/recent psychiatric patients using correlation and regression analyses, and also evaluated the incremental predictive power of other Section III traits. In addition, we tested the hypothesis that self-harm would incrementally predict BPD Criterion 5 over the Section III traits. Results supported Section III BPD traits as an adequate representation of traditional BPD symptomatology, although modifications that would increase intermodel continuity were identified. Finally, we found support for the incremental validity of suspiciousness, anhedonia, perceptual dysregulation, and self-harm, suggesting possible gaps in the Section III PD trait definitions. (PsycINFO Database Record

  16. MEDSLIK-II, a Lagrangian marine oil spill model for short-term forecasting - Part 1: Theory

    NASA Astrophysics Data System (ADS)

    De Dominicis, M.; Pinardi, N.; Zodiatis, G.

    2013-03-01

    The processes of transport, diffusion and transformation of surface oil in seawater can be simulated using a Lagrangian model formalism coupled with Eulerian circulation models. This paper describes the formalism and the conceptual assumptions of a Lagrangian marine oil slick numerical model and re-writes the constitutive equations in a modern mathematical framework. The Lagrangian numerical representation of the oil slick requires three different state variables: the slick, the particle and the structural state variables. Transformation processes (evaporation, spreading, dispersion and coastal adhesion) act on the slick state variables, while particles variables are used to model the transport and diffusion processes. The slick and particle variables are recombined together to compute the oil concentration in water, a structural state variable. The mathematical and numerical formulation of oil transport, diffusion and transformation processes described in this paper, together with the many simplifying hypothesis and parameterizations, form the basis of a new, open source Lagrangian surface oil spill model, so-called MEDSLIK-II. Part 2 of this paper describes the applications of MEDSLIK-II to oil spill simulations that allow the validation of the model results and the study of the sensitivity of the simulated oil slick to different model numerical parameterizations.

  17. Evidence from mathematical modeling that carbonic anhydrase II and IV enhance CO2 fluxes across Xenopus oocyte plasma membranes

    PubMed Central

    Musa-Aziz, Raif; Boron, Walter F.

    2014-01-01

    Exposing an oocyte to CO2/HCO3− causes intracellular pH (pHi) to decline and extracellular-surface pH (pHS) to rise to a peak and decay. The two companion papers showed that oocytes injected with cytosolic carbonic anhydrase II (CA II) or expressing surface CA IV exhibit increased maximal rate of pHi change (dpHi/dt)max, increased maximal pHS changes (ΔpHS), and decreased time constants for pHi decline and pHS decay. Here we investigate these results using refinements of an earlier mathematical model of CO2 influx into a spherical cell. Refinements include 1) reduced cytosolic water content, 2) reduced cytosolic diffusion constants, 3) refined CA II activity, 4) layer of intracellular vesicles, 5) reduced membrane CO2 permeability, 6) microvilli, 7) refined CA IV activity, 8) a vitelline membrane, and 9) a new simulation protocol for delivering and removing the bulk extracellular CO2/HCO3− solution. We show how these features affect the simulated pHi and pHS transients and use the refined model with the experimental data for 1.5% CO2/10 mM HCO3− (pHo = 7.5) to find parameter values that approximate ΔpHS, the time to peak pHS, the time delay to the start of the pHi change, (dpHi/dt)max, and the change in steady-state pHi. We validate the revised model against data collected as we vary levels of CO2/HCO3− or of extracellular HEPES buffer. The model confirms the hypothesis that CA II and CA IV enhance transmembrane CO2 fluxes by maximizing CO2 gradients across the plasma membrane, and it predicts that the pH effects of simultaneously implementing intracellular and extracellular-surface CA are supra-additive. PMID:24965589

  18. Evidence from mathematical modeling that carbonic anhydrase II and IV enhance CO2 fluxes across Xenopus oocyte plasma membranes.

    PubMed

    Occhipinti, Rossana; Musa-Aziz, Raif; Boron, Walter F

    2014-11-01

    Exposing an oocyte to CO2/HCO3 (-) causes intracellular pH (pHi) to decline and extracellular-surface pH (pHS) to rise to a peak and decay. The two companion papers showed that oocytes injected with cytosolic carbonic anhydrase II (CA II) or expressing surface CA IV exhibit increased maximal rate of pHi change (dpHi/dt)max, increased maximal pHS changes (ΔpHS), and decreased time constants for pHi decline and pHS decay. Here we investigate these results using refinements of an earlier mathematical model of CO2 influx into a spherical cell. Refinements include 1) reduced cytosolic water content, 2) reduced cytosolic diffusion constants, 3) refined CA II activity, 4) layer of intracellular vesicles, 5) reduced membrane CO2 permeability, 6) microvilli, 7) refined CA IV activity, 8) a vitelline membrane, and 9) a new simulation protocol for delivering and removing the bulk extracellular CO2/HCO3 (-) solution. We show how these features affect the simulated pHi and pHS transients and use the refined model with the experimental data for 1.5% CO2/10 mM HCO3 (-) (pHo = 7.5) to find parameter values that approximate ΔpHS, the time to peak pHS, the time delay to the start of the pHi change, (dpHi/dt)max, and the change in steady-state pHi. We validate the revised model against data collected as we vary levels of CO2/HCO3 (-) or of extracellular HEPES buffer. The model confirms the hypothesis that CA II and CA IV enhance transmembrane CO2 fluxes by maximizing CO2 gradients across the plasma membrane, and it predicts that the pH effects of simultaneously implementing intracellular and extracellular-surface CA are supra-additive. Copyright © 2014 the American Physiological Society.

  19. Dynamic Regime Marginal Structural Mean Models for Estimation of Optimal Dynamic Treatment Regimes, Part II: Proofs of Results*

    PubMed Central

    Orellana, Liliana; Rotnitzky, Andrea; Robins, James M.

    2010-01-01

    In this companion article to “Dynamic Regime Marginal Structural Mean Models for Estimation of Optimal Dynamic Treatment Regimes, Part I: Main Content” [Orellana, Rotnitzky and Robins (2010), IJB, Vol. 6, Iss. 2, Art. 7] we present (i) proofs of the claims in that paper, (ii) a proposal for the computation of a confidence set for the optimal index when this lies in a finite set, and (iii) an example to aid the interpretation of the positivity assumption. PMID:20405047

  20. Dynamic regime marginal structural mean models for estimation of optimal dynamic treatment regimes, Part II: proofs of results.

    PubMed

    Orellana, Liliana; Rotnitzky, Andrea; Robins, James M

    2010-03-03

    In this companion article to "Dynamic Regime Marginal Structural Mean Models for Estimation of Optimal Dynamic Treatment Regimes, Part I: Main Content" [Orellana, Rotnitzky and Robins (2010), IJB, Vol. 6, Iss. 2, Art. 7] we present (i) proofs of the claims in that paper, (ii) a proposal for the computation of a confidence set for the optimal index when this lies in a finite set, and (iii) an example to aid the interpretation of the positivity assumption.

  1. Assessment of dental arches in patients with Class II division 1 and division 2 malocclusions using 3D digital models in a Syrian sample.

    PubMed

    Hajeer, M Y

    2014-06-01

    (1) to evaluate the applicability of using 3D digital models in the assessment of Class II Division 1 (Cl II-1) and Class II Division 2 (Cl II-2) malocclusion in a Syrian sample, (2) to detect any significant differences between the two groups in tooth and arch widths, anterior (ABR) and overall Bolton ratios, PAR Index, and (3) to detect any gender differences in these variables. observational, cross-sectional study for descriptive and analytical purposes at the Orthodontic Dept., University of Al-Baath Hamah Dental School, Hamah, Syria. A disproportionate multi-stratified random sampling was employed to select 36 Cl II-1 and 36 Cl II-2 patients (female-to-male ratio was 1:1 in each group). 3D digital models (O3DM) with a dedicated programme were used to measure dental arch variables. Significant differences were observed between the two groups in the mesiodistal widths of some teeth but not in the dental arch widths. The prevalence of 'discrepancy cases' in Anterior Bolton Ratios (ABRs) was 33.33% and 41.67% in Cl II1 and Cl II2 groups, respectively. The mean PAR Index score was 25.36 and 20.82 for Cl II1 and Cl II2 groups, respectively (p=0.009). (1) 3D digital models enabled fast, accurate and reliable measurements of dental arch characteristics in patients with Class II malocclusion. (2) Insignificant differences between Cl II1 and Cl II2 patients were observed regarding Bolton's ratios and transverse arch measurements. (3) Sexual dimorphism was observed in mesiodistal tooth widths and in dental arch widths, but not in Bolton's ratios and PAR Index scores.

  2. Structural models for Cu(II) bound to the fragment 92-96 of the human prion protein.

    PubMed

    Grande-Aztatzi, Rafael; Rivillas-Acevedo, Lina; Quintanar, Liliana; Vela, Alberto

    2013-01-24

    The prion protein (PrP(C)) binds Cu(II) in its N-terminal region, and it is associated to a group of neurodegenerative diseases termed transmissible spongiform encephalopaties (TSEs). The isoform PrP(Sc), derived from the normal PrP(C), is the pathogenic agent of TSEs. Using spectroscopic techniques (UV-vis absorption, circular dichroism, and electron paramagnetic resonance) and electronic structure calculations, we obtained a structural description for the different pH-dependent binding modes of Cu(II) to the PrP(92-96) fragment. We have also evaluated the possibility of water molecule ligation to the His96-bound copper ion. Geometry-optimized structural models that reproduce the spectroscopic features of these complexes are presented. Two Cu(II) binding modes are relevant at physiological pH: 4N and 3NO equatorial coordination modes; these are best described by models with no participation of water molecules in the coordination sphere of the metal ion. In contrast, the 2N2O and N3O coordination modes that are formed at lower pH involve the coordination of an axial water molecule. This study underscores the importance of including explicit water molecules when modeling copper binding sites in PrP(C).

  3. Complex of manganese (II) with curcumin: Spectroscopic characterization, DFT study, model-based analysis and antiradical activity

    NASA Astrophysics Data System (ADS)

    Gorgannezhad, Lena; Dehghan, Gholamreza; Ebrahimipour, S. Yousef; Naseri, Abdolhossein; Nazhad Dolatabadi, Jafar Ezzati

    2016-04-01

    The complex formation between curcumin (Cur) and Manganese (II) chloride tetrahydrate (MnCl2.4H2O) was studied by UV-Vis and IR spectroscopy. Spectroscopic data suggest that Cur can chelate Manganese cations. A simple multi-wavelength model-based method was used to define stability constant for complexation reaction regardless of the spectra overlapping of components. Also, pure spectra and concentration profiles of all components were extracted using this method. Density functional theory (DFT) was also used to view insight into complexation mechanism. Antioxidant activity of Cur and Cur-Mn(II) complex was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging method. Bond dissociation energy (BDE), the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) and Molecular electrostatic potential (MEP) of Cur and the complex also were calculated at PW91/TZ2P level of theory using ADF 2009.01 package. The experimental results show that Cur has a higher DPPH radical scavenging activity than Cur-Mn(II). This observation is theoretically justified by means of lower BDE and higher HOMO and LUMO energy values of Cur ligand as compared with those of Cur-Mn(II) complex.

  4. Nitric oxide dynamics and endothelial dysfunction in type II model of genetic diabetes.

    PubMed

    Bitar, Milad S; Wahid, Sabah; Mustafa, Seham; Al-Saleh, Eyad; Dhaunsi, Gursev S; Al-Mulla, Fahd

    2005-03-21

    Although diabetes is a major risk factor for vascular diseases, e.g., hypertension and atherosclerosis, mechanisms that underlie the "risky" aspects of diabetes remain obscure. The current study is intended to examine the notion that diabetic endothelial dysfunction stems from a heightened state of oxidative stress induced by an imbalance between vascular production and scavenging of reactive oxygen/nitrogen species. Goto-Kakizaki (GK) rats were used as a genetic animal model for non-obese type II diabetes. Nitric oxide (NO) bioavailability and O2- generation in aortic tissues of GK rats were assessed using the Griess reaction and a lucigenin-chemiluminescence-based technique, respectively. Organ chamber-based isometric tension studies revealed that aortas from GK rats had impaired relaxation responses to acetylcholine whereas a rightward shift in the dose-response curve was noticed in the endothelium-independent vasorelaxation exerted by the NO donor sodium nitroprusside. An enhancement in superoxide (O2-) production and a diminuation in NO bioavailability were evident in aortic tissues of GK diabetic rats. Immunoblotting and high-performance liquid chromatography (HPLC)-based techniques revealed, respectively, that the above inverse relationship between O2- and NO was associated with a marked increase in the protein expression of nitric oxide synthase (eNOS) and a decrease in the level of its cofactor tetrahydrobiopterin (BH4) in diabetic aortas. Endothelial denudation by rubbing or the addition of pharmacological inhibitors of eNOS (e.g. N(omega)-nitro-L-arginine methyl ester (L-NAME)), and NAD(P)H oxidase (e.g. diphenyleneiodonium, apocynin) strikingly reduced the diabetes-induced enhancement in vascular O2- production. Aortic contents of key markers of oxidative stress (isoprostane F2alpha III, protein-bound carbonyls, nitrosylated protein) in connection with the protein expression of superoxide generating enzyme NAD(P)H oxidase (e.g. p47phox, pg91phox), a

  5. Combined Modeling of Acceleration, Transport, and Hydrodynamic Response in Solar Flares. II. Inclusion of Radiative Transfer with RADYN

    NASA Astrophysics Data System (ADS)

    Rubio da Costa, Fatima; Liu, Wei; Petrosian, Vahé; Carlsson, Mats

    2015-11-01

    Solar flares involve complex processes that are coupled and span a wide range of temporal, spatial, and energy scales. Modeling such processes self-consistently has been a challenge in the past. Here we present results from simulations that couple particle kinetics with hydrodynamics (HD) of the atmospheric plasma. We combine the Stanford unified Fokker-Planck code that models particle acceleration and transport with the RADYN HD code that models the atmospheric response to collisional heating by accelerated electrons through detailed radiative transfer calculations. We perform simulations using two different electron spectra, one an ad hoc power law and the other predicted by the model of stochastic acceleration by turbulence or plasma waves. Surprisingly, the later model, even with energy flux \\ll {10}10 {erg} {{{s}}}-1 {{cm}}-2, can cause “explosive” chromospheric evaporation and drive stronger up- and downflows (and HD shocks). This is partly because our acceleration model, like many others, produces a spectrum consisting of a quasi-thermal component plus a power-law tail. We synthesize emission-line profiles covering different heights in the lower atmosphere, including Hα 6563 Å, He ii 304 Å, Ca ii K 3934 Å, and Si iv 1393 Å. One interesting result is the unusual high temperature (up to a few times 105 K) of the formation site of He ii 304 Å, which is expected owing to photoionization-recombination under flare conditions, compared to those in the quiet Sun dominated by collisional excitation. When compared with observations, our results can constrain the properties of nonthermal electrons and thus the poorly understood particle acceleration mechanism.

  6. Synthesis, characterization, molecular modeling and antioxidant activity of (1E,5E)-1,5-bis(1-(pyridin-2-yl)ethylidene)carbonohydrazide (H2APC) and its zinc(II), cadmium(II) and mercury(II) complexes

    NASA Astrophysics Data System (ADS)

    El-Gammal, O. A.; Abu El-Reash, G. M.; Ghazy, S. E.; Radwan, A. H.

    2012-08-01

    A new series of Zn(II), Cd(II) and Hg(II) complexes of (1E,5E)-1,5-bis(1-(pyridin-2-yl)ethylidene)carbonohydrazide (H2APC) have been prepared and characterized by elemental analyses, spectral (IR, UV-visible, mass and 1H NMR) as well as magnetic and thermal measurements. The data revealed that the ligand acts a monobasic hexadentate, neutral tri- and monodentate in Zn(II), Cd(II) and Hg(II) complexes, respectively. An octahedral geometry is proposed for Zn(II) complex, a trigonal bi-pyramid for Cd(II) complex and a tetrahedral one for Hg(II) complex. The bond length, bond angle, HOMO, LUMO and charges on the atoms have been calculated to confirm the geometry of the ligand and the investigated complexes using material studio program. Kinetic parameters were determined for each thermal degradation stage of some complexes using Coats-Redfern and Horowitz-Metzger methods. The antioxidant, anti-hemolytic, and cytotoxic activities of the compounds have been screened. H2APC showed moderate antioxidant activity using ABTS and DPPH methods. With respect to erythrocyte hemolysis and in vitro Ehrlich ascites assay, H2APC exhibited the potent antioxidative activity followed by Cd(II) and Zn(II) complexes while Hg(II) complex showed very weak activity.

  7. Phylogenetic relationships and protein modelling revealed two distinct subfamilies of group II HKT genes between crop and model grasses.

    PubMed

    Ariyarathna, H A Chandima K; Francki, Michael G

    2016-07-01

    Molecular evolution of large protein families in closely related species can provide useful insights on structural functional relationships. Phylogenetic analysis of the grass-specific group II HKT genes identified two distinct subfamilies, I and II. Subfamily II was represented in all species, whereas subfamily I was identified only in the small grain cereals and possibly originated from an ancestral gene duplication post divergence from the coarse grain cereal lineage. The core protein structures were highly analogous despite there being no more than 58% amino acid identity between members of the two subfamilies. Distinctly variable regions in known functional domains, however, indicated functional divergence of the two subfamilies. The subsets of codons residing external to known functional domains predicted signatures of positive Darwinian selection potentially identifying new domains of functional divergence and providing new insights on the structural function and relationships between protein members of the two subfamilies.

  8. Geothermal completion technology life cycle cost model (GEOCOM). Volume I. Final report. Volume II. User instruction manual

    SciTech Connect

    Anderson, E.R.; Hoessel, W.C.; Mansure, A.J.; McKissen, P.

    1982-07-01

    Just as with petroleum wells, drilling and completing a geothermal well at minimum original cost may not be the most cost-effective way to exploit the resource. The impacts of the original completion activities on production and costs later in the life of the well must also be considered. In order to evaluate alternate completion and workover technologies, a simple computer model has been developed to compare total life-cycle costs for a geothermal well to total production or injection. Volume I discusses the mechanics of the model and then presents detailed results from its application to different completion and workover questions. Volume II is the user instruction manual.

  9. DISPOSITION OF TCDD IN A MOUSE MODEL OF OBESITY AND TYPE II DIABETESE

    EPA Science Inventory

    Recent epidemiology studies have shown an association between type II diabetes and exposure to TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin). A possible explanation is that diabetics have a slower elimination of TCDD than non-diabetics. The objective of the present study was to ex...

  10. Solar Irradiance Variations Modelled from Ca II K Excess and Magnetic Field

    NASA Astrophysics Data System (ADS)

    Vogler, F. L.; Brandt, P. N.; Otruba, W.; Hanslmeier, A.

    The facular contribution (Δ S(λ)/S(λ))_{f} to the variation of the total solar irradiance Δ S(λ)/S(λ), for two continuum wavelengths and for a period of 60 not consecutive days in 1999, is calculated according to two different methods, namely via RISE/PSPT Ca II K images and via magnetograms of the MDI instrument on board of the SOHO spacecraft. The results are correlated with the values of the total irradiance channel of the VIRGO instrument on board of SOHO. The correlation coefficient for the first method (via Ca II K images) is 0.55, and 0.23 for the second method (via magnetograms). Particularly with regard to faculae, Ca II K irradiance appears to be much more representative than the line-of-sight magnetic field. For use of the magnetograms the relationship between the Ca II K excess E_{k} and the line-of-sight magnetic flux density |B| is analysed. E_{k} is measured in dependence on the two variables μ and |B|. A multivariate fit yields a compact presentation of this function and the exponent β of the power law E_{k}=α\\cdot|B|^{β} is determined; the values 0.48≤ β ≤ 0.57 agree with those found by Harvey and White (1999).

  11. FORUM - FutureTox II: In vitro Data and In Silico Models for Predictive Toxicology

    EPA Science Inventory

    FutureTox II, a Society of Toxicology Contemporary Concepts in Toxicology workshop, was held in January, 2014. The meeting goals were to review and discuss the state of the science in toxicology in the context of implementing the NRC 21st century vision of predicting in vivo resp...

  12. Product-Improvement Test (Phase II), Jetcal Tester, Model H119A.

    DTIC Science & Technology

    1969-03-05

    1520-220-20. • ~~i~~aic. M Ii a• masb ., .f~~M * paa* •~ ~~~~~~~~~~D AT E tYP ED NAM E, lOADS. 0* TITk J 1 .l.NATU.e L. D. Griffin , Supv., Quality

  13. FORUM - FutureTox II: In vitro Data and In Silico Models for Predictive Toxicology

    EPA Science Inventory

    FutureTox II, a Society of Toxicology Contemporary Concepts in Toxicology workshop, was held in January, 2014. The meeting goals were to review and discuss the state of the science in toxicology in the context of implementing the NRC 21st century vision of predicting in vivo resp...

  14. DISPOSITION OF TCDD IN A MOUSE MODEL OF OBESITY AND TYPE II DIABETESE

    EPA Science Inventory

    Recent epidemiology studies have shown an association between type II diabetes and exposure to TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin). A possible explanation is that diabetics have a slower elimination of TCDD than non-diabetics. The objective of the present study was to ex...

  15. Comparison of the EXAFS Spectra of Heteronuclear MnCa/Sr Model Complexes to the Oxygen-Evolving Mn(4)Ca Complex of Photosystem II

    SciTech Connect

    Mishra, A.; Yano, J.; Pushkar, Y.; Abboud, K.A.; Yachandra, V.K.; Christou, G.

    2009-06-03

    Heterometallic Mn-Ca and Mn-Sr complexes have been prepared and employed as model complexes for Ca and Sr EXAFS spectral comparisons with the Oxygen-Evolving Complex (OEC) of Photosystem II (PS II); these have revealed similarities that support the presence of at least one O atom bridge between the Mn and Ca/Sr in the OEC.

  16. Phase II Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 98: Frenchman Flat, Nye County, Nevada, Rev. No.: 0

    SciTech Connect

    DeNovio, Nicole M.; Bryant, Nathan; King, Chrissi B.; Bhark, Eric; Drellack, Sigmund L.; Pickens, John F.; Farnham, Irene; Brooks, Keely M.; Reimus, Paul; Aly, Alaa

    2005-04-01

    This report documents pertinent transport data and data analyses as part of the Phase II Corrective Action Investigation (CAI) for Frenchman Flat (FF) Corrective Action Unit (CAU) 98. The purpose of this data compilation and related analyses is to provide the primary reference to support parameterization of the Phase II FF CAU transport model.

  17. Person Heterogeneity of the BDI-II-C and Its Effects on Dimensionality and Construct Validity: Using Mixture Item Response Models

    ERIC Educational Resources Information Center

    Wu, Pei-Chen; Huang, Tsai-Wei

    2010-01-01

    This study was to apply the mixed Rasch model to investigate person heterogeneity of Beck Depression Inventory-II-Chinese version (BDI-II-C) and its effects on dimensionality and construct validity. Person heterogeneity was reflected by two latent classes that differ qualitatively. Additionally, person heterogeneity adversely affected the…

  18. Phase II Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 98: Frenchman Flat, Nye County, Nevada, Rev. No.: 0

    SciTech Connect

    John McCord

    2004-12-01

    This report documents pertinent hydrologic data and data analyses as part of the Phase II Corrective Action Investigation (CAI) for Frenchman Flat (FF) Corrective Action Unit (CAU): CAU 98. The purpose of this data compilation and related analyses is to provide the primary reference to support the development of the Phase II FF CAU groundwater flow model.

  19. TEMPORAL EVOLUTION OF THE SCATTERING POLARIZATION OF THE Ca II IR TRIPLET IN HYDRODYNAMICAL MODELS OF THE SOLAR CHROMOSPHERE

    SciTech Connect

    Carlin, E. S.; Asensio Ramos, A.; Trujillo Bueno, J.

    2013-02-10

    Velocity gradients in a stellar atmospheric plasma have an effect on the anisotropy of the radiation field that illuminates each point within the medium, and this may in principle influence the scattering line polarization that results from the induced atomic level polarization. Here, we analyze the emergent linear polarization profiles of the Ca II infrared triplet after solving the radiative transfer problem of scattering polarization in time-dependent hydrodynamical models of the solar chromosphere, taking into account the effect of the plasma macroscopic velocity on the atomic level polarization. We discuss the influence that the velocity and temperature shocks in the considered chromospheric models have on the temporal evolution of the scattering polarization signals of the Ca II infrared lines as well as on the temporally averaged profiles. Our results indicate that the increase of the linear polarization amplitudes caused by macroscopic velocity gradients may be significant in realistic situations. We also study the effect of the integration time, the microturbulent velocity, and the photospheric dynamical conditions, and discuss the feasibility of observing with large-aperture telescopes the temporal variation of the scattering polarization profiles. Finally, we explore the possibility of using a Hanle effect line-ratio technique in the IR triplet of Ca II to facilitate magnetic field diagnostics in dynamic situations.

  20. Biosorption of cobalt(II) with sunflower biomass from aqueous solutions in a fixed bed column and neural networks modelling.

    PubMed

    Oguz, Ensar; Ersoy, Muhammed

    2014-01-01

    The effects of inlet cobalt(II) concentration (20-60 ppm), feed flow rate (8-19 ml/min) and bed height (5-15 cm), initial solution pH (3-5) and pa