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Sample records for selective facilitated transport

  1. Selective removal of carbon dioxide from wet CO{sub 2}/H{sub 2} mixtures via facilitated transport membranes containing amine blends as carriers

    Energy Technology Data Exchange (ETDEWEB)

    Heydari Gorji, A. [Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran (Iran); Kargari, A. [Department of Mechanical Engineering, K. N. Toosi University of Technology, Tehran (Iran); Kaghazchi, T.

    2009-01-15

    The selective separation of carbon dioxide (CO{sub 2}) from a wet gaseous mixture of CO{sub 2}/H{sub 2} through facilitated transport membranes containing immobilized aqueous solutions of monoethanolamine (MEA), diethanolamine (DEA), ethylenediamine (EDA) and monoprotonated ethylenediamine (EDAH{sup +}) and their blends was experimentally investigated. The effect of CO{sub 2} partial pressure, amine concentration, feed side pressure and amine species on the CO{sub 2} and H{sub 2} permeances were studied. The CO{sub 2} permeability through amine solution membranes decreased with increasing CO{sub 2} feed partial pressure but the H{sub 2} permeance was almost independent of the H{sub 2} partial pressure. A comparison of experimental results showed that single or blended amines with low viscosity and a moderate equilibrium constant, i.e., large forward and reverse reaction rate of CO{sub 2}-amine, are suitable for effective separation of CO{sub 2}. The permeability of CO{sub 2} generally increased with an increase in amine concentration, although this increase may be compromised by the salting out effect and decrease in diffusivities of species. The results obtained indicated that CO{sub 2} permeance across a variety of amines are in the order of DEA (2 M)>MD(2M) >MD(1 M)>MEA(2 M) >MEA(4 M)>MD (4 M)>DEA (1 M)> DEA(4 M)>MEA (1 M) for various concentrations of MEA+DEA blend and are in the order of EDAH{sup +}(2 M)> DEA(2 M) >MH(2 M)>DH (2 M)>ED (2 M)>EDA (2 M)> MEA(2 M) for various blends of amine. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  2. Molecular Tools for Facilitative Carbohydrate Transporters (Gluts).

    Science.gov (United States)

    Tanasova, Marina; Fedie, Joseph R

    2017-09-19

    Facilitative carbohydrate transporters-Gluts-have received wide attention over decades due to their essential role in nutrient uptake and links with various metabolic disorders, including diabetes, obesity, and cancer. Endeavors directed towards understanding the mechanisms of Glut-mediated nutrient uptake have resulted in a multidisciplinary research field spanning protein chemistry, chemical biology, organic synthesis, crystallography, and biomolecular modeling. Gluts became attractive targets for cancer research and medicinal chemistry, leading to the development of new approaches to cancer diagnostics and providing avenues for cancer-targeting therapeutics. In this review, the current state of knowledge of the molecular interactions behind Glut-mediated sugar uptake, Glut-targeting probes, therapeutics, and inhibitors are discussed. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Saturated Zone Colloid-Facilitated Transport

    International Nuclear Information System (INIS)

    Wolfsberg, A.; Reimus, P.

    2001-01-01

    The purpose of the Saturated Zone Colloid-Facilitated Transport Analysis and Modeling Report (AMR), as outlined in its Work Direction and Planning Document (CRWMS MandO 1999a), is to provide retardation factors for colloids with irreversibly-attached radionuclides, such as plutonium, in the saturated zone (SZ) between their point of entrance from the unsaturated zone (UZ) and downgradient compliance points. Although it is not exclusive to any particular radionuclide release scenario, this AMR especially addresses those scenarios pertaining to evidence from waste degradation experiments, which indicate that plutonium and perhaps other radionuclides may be irreversibly attached to colloids. This report establishes the requirements and elements of the design of a methodology for calculating colloid transport in the saturated zone at Yucca Mountain. In previous Total Systems Performance Assessment (TSPA) analyses, radionuclide-bearing colloids were assumed to be unretarded in their migration. Field experiments in fractured tuff at Yucca Mountain and in porous media at other sites indicate that colloids may, in fact, experience retardation relative to the mean pore-water velocity, suggesting that contaminants associated with colloids should also experience some retardation. Therefore, this analysis incorporates field data where available and a theoretical framework when site-specific data are not available for estimating plausible ranges of retardation factors in both saturated fractured tuff and saturated alluvium. The distribution of retardation factors for tuff and alluvium are developed in a form consistent with the Performance Assessment (PA) analysis framework for simulating radionuclide transport in the saturated zone. To improve on the work performed so far for the saturated-zone flow and transport modeling, concerted effort has been made in quantifying colloid retardation factors in both fractured tuff and alluvium. The fractured tuff analysis used recent data

  4. Thiacalix[4]arene derivatives as extractants for metal ions in aqueous solutions: Application to the selective facilitated transport of Ag(I)

    Energy Technology Data Exchange (ETDEWEB)

    Zaghbani, Asma [Laboratoire Eau et Technologies Membranaires, CERTE, BP 273, 8020 Soliman (Tunisia); Fontas, Claudia [Department of Chemistry, University of Girona, 17071 Girona (Spain)], E-mail: claudia.fontas@udg.edu; Hidalgo, Manuela [Department of Chemistry, University of Girona, 17071 Girona (Spain); Tayeb, Rafik; Dhahbi, Mahmoud [Laboratoire Eau et Technologies Membranaires, CERTE, BP 273, 8020 Soliman (Tunisia); Vocanson, Francis; Lamartine, Roger [Universite de Lyon, Lyon, F-69003 (France); Universite Lyon 1, Villeurbanne, F-69622 (France); CNRS, UMR 5246, ICBMS, equipe CSAp, 43 boulevard du 11 novembre 1918, Villeurbanne, F-69622 (France); Seta, Patrick [Institut Europeen des Membranes, UMR CNRS 5635, 1919 route de Mende, 34293 Montpellier (France)

    2008-07-01

    The complexation abilities of different thiacalix[4]arene derivatives towards some rare earth metal ions, metallic pollutants, and noble metals have been investigated in liquid-liquid experiments. Thiacalix[4]arene dissolved in chloroform effectively extracts Pd(II) (in acidic chloride media) and also Ag(I), Cd(II), Sm(III) and Ce(III), all buffered at pH 6 or 8. The modification of this compound to form an amide derivative results in an effective extraction of noble metals, ranked according to Au(III) > Pd(II) > Pt(IV) > Ag(I). Moreover, a supported liquid membrane system for silver transport has been developed based on thiacalix[4]arene dissolved in NPOE, and parameters affecting its efficiency have been investigated, such as the stripping composition and the pH of the feed solution. Finally, the selectivity of the membrane system has been evaluated by using as feed sources mixtures of silver and other metal ion000.

  5. Aluminum-Activated Malate Transporters Can Facilitate GABA Transport.

    Science.gov (United States)

    Ramesh, Sunita A; Kamran, Muhammad; Sullivan, Wendy; Chirkova, Larissa; Okamoto, Mamoru; Degryse, Fien; McLaughlin, Michael; Gilliham, Matthew; Tyerman, Stephen D

    2018-05-01

    Plant aluminum-activated malate transporters (ALMTs) are currently classified as anion channels; they are also known to be regulated by diverse signals, leading to a range of physiological responses. Gamma-aminobutyric acid (GABA) regulation of anion flux through ALMT proteins requires a specific amino acid motif in ALMTs that shares similarity with a GABA binding site in mammalian GABA A receptors. Here, we explore why TaALMT1 activation leads to a negative correlation between malate efflux and endogenous GABA concentrations ([GABA] i ) in both wheat ( Triticum aestivum ) root tips and in heterologous expression systems. We show that TaALMT1 activation reduces [GABA] i because TaALMT1 facilitates GABA efflux but GABA does not complex Al 3+ TaALMT1 also leads to GABA transport into cells, demonstrated by a yeast complementation assay and via 14 C-GABA uptake into TaALMT1 -expressing Xenopus laevis oocytes; this was found to be a general feature of all ALMTs we examined. Mutation of the GABA motif (TaALMT1 F213C ) prevented both GABA influx and efflux, and resulted in no correlation between malate efflux and [GABA] i We conclude that ALMTs are likely to act as both GABA and anion transporters in planta. GABA and malate appear to interact with ALMTs in a complex manner to regulate each other's transport, suggestive of a role for ALMTs in communicating metabolic status. © 2018 American Society of Plant Biologists. All rights reserved.

  6. Recent achievements in facilitated transport membranes for separation processes

    Directory of Open Access Journals (Sweden)

    H. C. Ferraz

    2007-03-01

    Full Text Available Membrane separation processes have been extensively used for some important industrial separations, substituting traditional methods. However, some applications require the development of new membranes. In this work, we discuss recent progress achieved in this field, focusing on gas and liquid separation using facilitated transport membranes. The advantages of using a carrier species either in a liquid membrane or fixed in a polymer matrix to enhance both the flux and the selectivity of the transport are summarized. The most probable transport mechanisms in these membranes are presented and the improvements needed to spread this technology are also discussed. As examples, we discuss our very successful experiences in air fractioning, olefin/paraffin separation and sugar recovery using liquid and fixed carrier membranes.

  7. Ocean transport and the facilitation of trade

    NARCIS (Netherlands)

    Veenstra, A.W.; Lee, C.Y.; Meng, Q.

    2015-01-01

    In this chapter, we describe transactions in international trade transaction, and we zoom in on the ocean transport part of that transaction. We use transaction cost economics as our theoretical framework. We highlighted a number of ocean transport related processes that generate uncertainty and

  8. Efficiency, selectivity, and robustness of nucleocytoplasmic transport.

    Directory of Open Access Journals (Sweden)

    Anton Zilman

    2007-07-01

    Full Text Available All materials enter or exit the cell nucleus through nuclear pore complexes (NPCs, efficient transport devices that combine high selectivity and throughput. NPC-associated proteins containing phenylalanine-glycine repeats (FG nups have large, flexible, unstructured proteinaceous regions, and line the NPC. A central feature of NPC-mediated transport is the binding of cargo-carrying soluble transport factors to the unstructured regions of FG nups. Here, we model the dynamics of nucleocytoplasmic transport as diffusion in an effective potential resulting from the interaction of the transport factors with the flexible FG nups, using a minimal number of assumptions consistent with the most well-established structural and functional properties of NPC transport. We discuss how specific binding of transport factors to the FG nups facilitates transport, and how this binding and competition between transport factors and other macromolecules for binding sites and space inside the NPC accounts for the high selectivity of transport. We also account for why transport is relatively insensitive to changes in the number and distribution of FG nups in the NPC, providing an explanation for recent experiments where up to half the total mass of the FG nups has been deleted without abolishing transport. Our results suggest strategies for the creation of artificial nanomolecular sorting devices.

  9. Colloid-Facilitated Transport of Radionuclides Through The Vadose Zone

    International Nuclear Information System (INIS)

    Markus Flury; James B. Harsh; John F. McCarthy' Peter C. Lichtner; John M. Zachara

    2007-01-01

    The main purpose of this project was to advance the basic scientific understanding of colloid and colloid-facilitated Cs transport of radionuclides in the vadose zone. We focused our research on the hydrological and geochemical conditions beneath the leaking waste tanks at the USDOE Hanford reservation. Specific objectives were (1) to determine the lability and thermodynamic stability of colloidal materials, which form after reacting Hanford sediments with simulated Hanford Tank Waste, (2) to characterize the interactions between colloidal particles and contaminants, i.e., Cs and Eu, (3) to determine the potential of Hanford sediments for in situ mobilization of colloids, (4) to evaluate colloid-facilitated radionuclide transport through sediments under unsaturated flow, (5) to implement colloid-facilitated contaminant transport mechanisms into a transport model, and (6) to improve conceptual characterization of colloid-contaminant-soil interactions and colloid-facilitated transport for clean-up procedures and long-term risk assessment

  10. Modeling CO2-facilitated transport across a diethanolamine liquid membrane

    Energy Technology Data Exchange (ETDEWEB)

    Lihong Bao; Michael C. Trachtenberg [Carbozyme Inc., Monmouth Junction, NJ (United States)

    2005-12-15

    We compared experimental and model data for the facilitated transport of CO2 from a CO2-air mixture across an aqueous solution of diethanolamine (DEA) via a hollow fiber, contained liquid membrane (HFCLM) permeator. A two-step carbamate formation model was devised to analyze the data instead of the one-step mechanism used by previous investigators. The effects of DEA concentration, liquid membrane thickness and feed CO2 concentration were also studied. With a 20% (wt) DEA liquid membrane and feed of 15% CO2 in CO2-air mixture at atmosphere pressure, the permeance reached 1.51E-8 mol/m{sup 2} s Pa with a CO2/N2 selectivity of 115. Model predictions compared well with the experimental results at CO2 concentrations of industrial importance. Short-term stability of the HFCLM permeator performance was examined. The system was stable during 5-days of testing.

  11. Colloid-Facilitated Transport of Radionuclides through the Vadose Zone

    International Nuclear Information System (INIS)

    Flury, Markus; Harsh, James B.; Zachara, John M.; McCarthy, John F.; Lichtner, Peter C.

    2006-01-01

    This project seeks to improve the basic understanding of the role of colloids in facilitating the transport of contaminants in the vadose zone. We focus on three major thrusts: (1) thermodynamic stability and mobility of colloids formed by reactions of sediments with highly alkaline tank waste solutions, (2) colloid-contaminant interactions, and (3) in-situ colloid mobilization and colloid facilitated contaminant transport occurring in both contaminated and uncontaminated Hanford sediments

  12. Facilitated transport of copper with hydroxyapatite nanoparticles in saturated sand

    Science.gov (United States)

    Saturated packed column experiments were conducted to investigate the facilitated transport of Cu with hydroxyapatite nanoparticles (nHAP) at different pore water velocities (0.22-2.2 cm min–1), solution pH (6.2-9.0), and fraction of Fe oxide coating on grain surfaces (', 0-0.36). The facilitated tr...

  13. "Facilitated" amino acid transport is upregulated in brain tumors.

    Science.gov (United States)

    Miyagawa, T; Oku, T; Uehara, H; Desai, R; Beattie, B; Tjuvajev, J; Blasberg, R

    1998-05-01

    The goal of this study was to determine the magnitude of "facilitated" amino acid transport across tumor and brain capillaries and to evaluate whether amino acid transporter expression is "upregulated" in tumor vessels compared to capillaries in contralateral brain tissue. Aminocyclopentane carboxylic acid (ACPC), a non-metabolized [14C]-labeled amino acid, and a reference molecule for passive vascular permeability, [67Ga]-gallium-diethylenetriaminepentaacetic acid (Ga-DTPA), were used in these studies. Two experimental rat gliomas were studied (C6 and RG2). Brain tissue was rapidly processed for double label quantitative autoradiography 10 minutes after intravenous injection of ACPC and Ga-DTPA. Parametric images of blood-to-brain transport (K1ACPC and K1Ga-DTPA, microL/min/g) produced from the autoradiograms and the histology were obtained from the same tissue section. These three images were registered in an image array processor; regions of interest in tumor and contralateral brain were defined on morphologic criteria (histology) and were transferred to the autoradiographic images to obtain mean values. The facilitated component of ACPC transport (deltaK1ACPC) was calculated from the K1ACPC and K1Ga-DTPA data, and paired comparisons between tumor and contralateral brain were performed. ACPC flux, K1ACPC, across normal brain capillaries (22.6 +/- 8.1 microL/g/min) was >200-fold greater than that of Ga-DTPA (0.09 +/- 0.04 microL/g/min), and this difference was largely (approximately 90%) due to facilitated ACPC transport. Substantially higher K1ACPC values compared to corresponding K1DTPA values were also measured in C6 and RG2 gliomas. The deltaK1ACPC values for C6 glioma were more than twice that of contralateral brain cortex. K1ACPC and deltaK1ACPC values for RG2 gliomas was not significantly higher than that of contralateral cortex, although a approximately 2-fold difference in facilitated transport is obtained after normalization for differences in capillary

  14. COLLOID-FACILITATED TRANSPORT OF RADIONUCLIDES THROUGH THE VADOSE ZONE

    International Nuclear Information System (INIS)

    Flury, Markus

    2003-01-01

    Contaminants have leaked into the vadose zone at the USDOE Hanford reservation. It is important to understand the fate and transport of these contaminants to design remediation strategies and long-term waste management plans at the Hanford reservation. Colloids may play an important role in fate and transport of strongly sorbing contaminants, such as Cs or Pu. This project seeks to improve the basic understanding of colloid and colloid-facilitated transport of contaminants in the vadose zone. The specific objectives addressed are: (1) Determine the structure, composition, and surface charge characteristics of colloidal particles formed under conditions similar to those occurring during leakage of waste typical of Hanford tank supernatants into soils and sediments surrounding the tanks. (2) Characterize the mutual interactions between colloids, contaminant, and soil matrix in batch experiments under various ionic strength and pH conditions. We will investigate the nature of the solid-liquid interactions and the kinetics of the reactions. (3) Evaluate mobility of colloids through soil under different degrees of water saturation and solution chemistry (ionic strength and pH). (4) Determine the potential of colloids to act as carriers to transport the contaminant through the vadose zone and verify the results through comparison with field samples collected under leaking tanks. (5) Improve conceptual characterization of colloid-contaminant-soil interactions and colloid-facilitated transport for implementation into reactive chemical transport models. This project was in part supported by an NSF-IGERT grant to Washington State University. The IGERT grant provided funding for graduate student research and education, and two graduate students were involved in the EMSP project. The IGERT program also supported undergraduate internships. The project is part of a larger EMSP program to study fate and transport of contaminants under leaking Hanford waste tanks. The project has

  15. Colloid-facilitated radionuclide transport: a regulatory perspective

    Science.gov (United States)

    Dam, W. L.; Pickett, D. A.; Codell, R. B.; Nicholson, T. J.

    2001-12-01

    What hydrogeologic-geochemical-microbial conditions and processes affect migration of radionuclides sorbed onto microparticles or native colloid-sized radionuclide particles? The U.S. Nuclear Regulatory Commission (NRC) is responsible for protecting public health, safety, and the environment at numerous nuclear facilities including a potential high-level nuclear waste disposal site. To fulfill these obligations, NRC needs to understand the mechanisms controlling radionuclide release and transport and their importance to performance. The current focus of NRC staff reviews and technical interactions dealing with colloid-facilitated transport relates to the potential nuclear-waste repository at Yucca Mountain, Nevada. NRC staff performed bounding calculations to quantify radionuclide releases available for ground-water transport to potential receptors from a Yucca Mountain repository. Preliminary analyses suggest insignificant doses of plutonium and americium colloids could be derived from spent nuclear fuel. Using surface complexation models, NRC staff found that colloids can potentially lower actinide retardation factors by up to several orders of magnitude. Performance assessment calculations, in which colloidal transport of plutonium and americium was simulated by assuming no sorption or matrix diffusion, indicated no effect of colloids on human dose within the 10,000 year compliance period due largely to long waste-package lifetimes. NRC staff have identified information gaps and developed technical agreements with the U.S. Department of Energy (DOE) to ensure sufficient information will be presented in any potential future Yucca Mountain license application. DOE has agreed to identify which radionuclides could be transported via colloids, incorporate uncertainties in colloid formation, release and transport parameters, and conceptual models, and address the applicability of field data using synthetic microspheres as colloid analogs. NRC is currently

  16. A GoldSim Model for Colloid Facilitated Nuclide Transport

    International Nuclear Information System (INIS)

    Lee, Youn Myoung; Jeong, Jong Tae

    2010-01-01

    Recently several total system performance assessment (TSPA) programs, called 'template' programs, ready for the safety assessment of radioactive waste repository systems which are conceptually modeled have been developed by utilizing GoldSim and AMBER at KAERI. It is generally believed that chelating agents (chelators) that could be disposed of together with radioactive wastes in the repository and natural colloids available in the geological media affect on nuclides by enhancing their transport in the geological media. A simple GoldSim module to evaluate such quantitative effects, by which colloid and chelator-facilitated nuclide release cases could be modeled and evaluated is introduced. Effects of the chelators alone are illustrated with the case associated with well pumping scenario in a hypothetical repository system

  17. Facilitated ion transport in all-solid-state flexible supercapacitors.

    Science.gov (United States)

    Choi, Bong Gill; Hong, Jinkee; Hong, Won Hi; Hammond, Paula T; Park, HoSeok

    2011-09-27

    The realization of highly flexible and all-solid-state energy-storage devices strongly depends on both the electrical properties and mechanical integrity of the constitutive materials and the controlled assembly of electrode and solid electrolyte. Herein we report the preparation of all-solid-state flexible supercapacitors (SCs) through the easy assembly of functionalized reduced graphene oxide (f-RGO) thin films (as electrode) and solvent-cast Nafion electrolyte membranes (as electrolyte and separator). In particular, the f-RGO-based SCs (f-RGO-SCs) showed a 2-fold higher specific capacitance (118.5 F/g at 1 A/g) and rate capability (90% retention at 30 A/g) compared to those of all-solid-state graphene SCs (62.3 F/g at 1A/g and 48% retention at 30 A/g). As proven by the 4-fold faster relaxation of the f-RGO-SCs than that of the RGO-SCs and more capacitive behavior of the former at the low-frequency region, these results were attributed to the facilitated ionic transport at the electrical double layer by means of the interfacial engineering of RGO by Nafion. Moreover, the superiority of all-solid-state flexible f-RGO-SCs was demonstrated by the good performance durability under the 1000 cycles of charging and discharging due to the mechanical integrity as a consequence of the interconnected networking structures. Therefore, this research provides new insight into the rational design and fabrication of all-solid-state flexible energy-storage devices as well as the fundamental understanding of ion and charge transport at the interface. © 2011 American Chemical Society

  18. Sugar transporter genes of the brown planthopper, Nilaparvata lugens: A facilitated glucose/fructose transporter.

    Science.gov (United States)

    Kikuta, Shingo; Kikawada, Takahiro; Hagiwara-Komoda, Yuka; Nakashima, Nobuhiko; Noda, Hiroaki

    2010-11-01

    The brown planthopper (BPH), Nilaparvata lugens, attacks rice plants and feeds on their phloem sap, which contains large amounts of sugars. The main sugar component of phloem sap is sucrose, a disaccharide composed of glucose and fructose. Sugars appear to be incorporated into the planthopper body by sugar transporters in the midgut. A total of 93 expressed sequence tags (ESTs) for putative sugar transporters were obtained from a BPH EST database, and 18 putative sugar transporter genes (Nlst1-18) were identified. The most abundantly expressed of these genes was Nlst1. This gene has previously been identified in the BPH as the glucose transporter gene NlHT1, which belongs to the major facilitator superfamily. Nlst1, 4, 6, 9, 12, 16, and 18 were highly expressed in the midgut, and Nlst2, 7, 8, 10, 15, 17, and 18 were highly expressed during the embryonic stages. Functional analyses were performed using Xenopus oocytes expressing NlST1 or 6. This showed that NlST6 is a facilitative glucose/fructose transporter that mediates sugar uptake from rice phloem sap in the BPH midgut in a manner similar to NlST1. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Selective Ionic Transport Pathways in Phosphorene.

    Science.gov (United States)

    Nie, Anmin; Cheng, Yingchun; Ning, Shoucong; Foroozan, Tara; Yasaei, Poya; Li, Wen; Song, Boao; Yuan, Yifei; Chen, Lin; Salehi-Khojin, Amin; Mashayek, Farzad; Shahbazian-Yassar, Reza

    2016-04-13

    Despite many theoretical predictions indicating exceptionally low energy barriers of ionic transport in phosphorene, the ionic transport pathways in this two-dimensional (2D) material has not been experimentally demonstrated. Here, using in situ aberration-corrected transmission electron microscopy (TEM) and density functional theory, we studied sodium ion transport in phosphorene. Our high-resolution TEM imaging complemented by electron energy loss spectroscopy demonstrates a precise description of anisotropic sodium ions migration along the [100] direction in phosphorene. This work also provides new insight into the effect of surface and the edge sites on the transport properties of phosphorene. According to our observation, the sodium ion transport is preferred in zigzag edge rather than the armchair edge. The use of this highly selective ionic transport property may endow phosphorene with new functionalities for novel chemical device applications.

  20. Facilitation of Nanoscale Thermal Transport by Hydrogen Bonds

    OpenAIRE

    Zhang, Lin

    2017-01-01

    Thermal transport performance at the nanoscale and/or of biomaterials is essential to the success of many new technologies including nanoelectronics, biomedical devices, and various nanocomposites. Due to complicated microstructures and chemical bonding, thermal transport process in these materials has not been well understood yet. In terms of chemical bonding, it is well known that the strength of atomic bonding can significantly affect thermal transport across materials or across interfaces...

  1. Go girl! Facilitating exploration of transportation careers for girls

    Science.gov (United States)

    2007-07-01

    The transportation engineering profession, like every other profession that relies heavily on the engineering, technology and science fields, faces a challenging future. A recent study by the National Science Board reported a troubling decline in the...

  2. Colloid Facilitated Transport of Radioactive Cations in the Vadose Zone: Field Experiments Oak Ridge

    Energy Technology Data Exchange (ETDEWEB)

    James E. Saiers

    2012-09-20

    The overarching goal of this study was to improve understanding of colloid-facilitated transport of radioactive cations through unsaturated soils and sediments. We conducted a suite of laboratory experiments and field experiments on the vadose-zone transport of colloids, organic matter, and associated contaminants of interest to the U.S. Department of Energy (DOE). The laboratory and field experiments, together with transport modeling, were designed to accomplish the following detailed objectives: 1. Evaluation of the relative importance of inorganic colloids and organic matter to the facilitation of radioactive cation transport in the vadose zone; 2. Assessment of the role of adsorption and desorption kinetics in the facilitated transport of radioactive cations in the vadose zone; 3. Examination of the effects of rainfall and infiltration dynamics and in the facilitated transport of radioactive cations through the vadose zone; 4. Exploration of the role of soil heterogeneity and preferential flow paths (e.g., macropores) on the facilitated transport of radioactive cations in the vadose zone; 5. Development of a mathematical model of facilitated transport of contaminants in the vadose zone that accurately incorporates pore-scale and column-scale processes with the practicality of predicting transport with readily available parameters.

  3. Modeling particle-facilitated solute transport using the C-Ride module of HYDRUS

    Science.gov (United States)

    Simunek, Jiri; Bradford, Scott A.

    2017-04-01

    Strongly sorbing chemicals (e.g., heavy metals, radionuclides, pharmaceuticals, and/or explosives) in soils are associated predominantly with the solid phase, which is commonly assumed to be stationary. However, recent field- and laboratory-scale observations have shown that, in the presence of mobile colloidal particles (e.g., microbes, humic substances, clays and metal oxides), the colloids could act as pollutant carriers and thus provide a rapid transport pathway for strongly sorbing contaminants. Such transport can be further accelerated since these colloidal particles may travel through interconnected larger pores where the water velocity is relatively high. Additionally, colloidal particles have a considerable adsorption capacity for other species present in water because of their large specific surface areas and their high concentrations in soil-water and groundwater. As a result, the transport of contaminants can be significantly, sometimes dramatically, enhanced when they are adsorbed to mobile colloids. To address this problem, we have developed the C-Ride module for HYDRUS-1D. This one-dimensional numerical module is based on the HYDRUS-1D software package and incorporates mechanisms associated with colloid and colloid-facilitated solute transport in variably saturated porous media. This numerical model accounts for both colloid and solute movement due to convection, diffusion, and dispersion in variably-saturated soils, as well as for solute movement facilitated by colloid transport. The colloids transport module additionally considers processes of attachment/detachment to/from the solid phase, straining, and/or size exclusion. Various blocking and depth dependent functions can be used to modify the attachment and straining coefficients. The module additionally considers the effects of changes in the water content on colloid/bacteria transport and attachment/detachment to/from solid-water and air-water interfaces. For example, when the air

  4. Crowding-facilitated macromolecular transport in attractive micropost arrays.

    Science.gov (United States)

    Chien, Fan-Tso; Lin, Po-Keng; Chien, Wei; Hung, Cheng-Hsiang; Yu, Ming-Hung; Chou, Chia-Fu; Chen, Yeng-Long

    2017-05-02

    Our study of DNA dynamics in weakly attractive nanofabricated post arrays revealed crowding enhances polymer transport, contrary to hindered transport in repulsive medium. The coupling of DNA diffusion and adsorption to the microposts results in more frequent cross-post hopping and increased long-term diffusivity with increased crowding density. We performed Langevin dynamics simulations and found maximum long-term diffusivity in post arrays with gap sizes comparable to the polymer radius of gyration. We found that macromolecular transport in weakly attractive post arrays is faster than in non-attractive dense medium. Furthermore, we employed hidden Markov analysis to determine the transition of macromolecular adsorption-desorption on posts and hopping between posts. The apparent free energy barriers are comparable to theoretical estimates determined from polymer conformational fluctuations.

  5. Fabrication of CO2 Facilitated Transport Channels in Block Copolymer through Supramolecular Assembly

    Directory of Open Access Journals (Sweden)

    Yao Wang

    2014-05-01

    Full Text Available In this paper, the molecule 12-amidine dodecanoic acid (M with ending groups of carboxyl and amidine groups respectively was designed and synthesized as CO2-responsive guest molecules. The block copolymer polystyrene-b-polyethylene oxide (PS-b-PEO was chosen as the host polymer to fabricate a composite membrane through H-bonding assembly with guest molecule M. We attempted to tune the phase separation structure of the annealed film by varying the amount of M added, and investigated the nanostructures via transmission electron microscope (TEM, fourier transform infrared (FT-IR etc. As a result, a reverse worm-like morphology in TEM image of bright PS phase in dark PEO/M matrix was observed for PS-b-PEO/M1 membrane in which the molar ratio of EO unit to M was 1:1. The following gas permeation measurement indicated that the gas flux of the annealed membranes dramatically increased due to the forming of ordered phase separation structure. As we expected, the obtained composite membrane PS-b-PEO/M1 with EO:M mole ratio of 1:1 presented an evident selectivity for moist CO2 permeance, which is identical with our initial proposal that the guest molecule M in the membranes will play the key role for CO2 facilitated transportation since the amidine groups of M could react reversibly with CO2 molecules in membranes. This work provides a supramolecular approach to fabricating CO2 facilitated transport membranes.

  6. Hydrogen vacancies facilitate hydrogen transport kinetics in sodium hydride nanocrystallites

    NARCIS (Netherlands)

    Singh, S.; Eijt, S.W.H.

    2008-01-01

    We report ab initio calculations based on density-functional theory, of the vacancy-mediated hydrogen migration energy in bulk NaH and near the NaH(001) surface. The estimated rate of the vacancy mediated hydrogen transport, obtained within a hopping diffusion model, is consistent with the reaction

  7. Biologically inspired water purification through selective transport

    International Nuclear Information System (INIS)

    Freeman, E C; Soncini, R M; Weiland, L M

    2013-01-01

    Biologically inspired systems based on cellular mechanics demonstrate the ability to selectively transport ions across a bilayer membrane. These systems may be observed in nature in plant roots, which remove select nutrients from the surrounding soil against significant concentration gradients. Using biomimetic principles in the design of tailored active materials allows for the development of selective membranes for capturing and filtering targeted ions. Combining this biomimetic transport system with a method for reclaiming the captured ions will allow for increased removal potential. To illustrate this concept, a device for removing nutrients from waterways to aid in reducing eutrophication is outlined and discussed. Presented is a feasibility study of various cellular configurations designed for this purpose, focusing on maximizing nutrient uptake. The results enable a better understanding of the benefits and obstacles when developing these cellularly inspired systems. (paper)

  8. Facilitated transport in hydroxide-exchange membranes for post-combustion CO2 separation.

    Science.gov (United States)

    Xiong, Laj; Gu, Shuang; Jensen, Kurt O; Yan, Yushan S

    2014-01-01

    Hydroxide-exchange membranes are developed for facilitated transport CO2 in post-combustion flue-gas feed. First, a correlation between the basicity of fixed-site functional groups and CO2 -separation performance is discovered. This relationship is used to identify phosphonium as a promising candidate to achieve high CO2 -separation performance. Consequently, quaternary phosphonium-based hydroxide-exchange membranes are demonstrated to have a separation performance that is above the Robeson upper bound. Specifically, a CO2 permeability as high as 1090 Barrer and a CO2 /N2 selectivity as high as 275 is achieved. The high performance observed in the membranes can be attributed to the quaternary phosphonium moiety. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Functional mining of transporters using synthetic selections

    DEFF Research Database (Denmark)

    Genee, Hans Jasper; Bali, Anne Pihl; Petersen, Søren Dalsgård

    2016-01-01

    transporters, PnuT, which is widely distributed across multiple bacterial phyla. We demonstrate that with modular replacement of the biosensor, we could expand our method to xanthine and identify xanthine permeases from gut and soil metagenomes. Our results demonstrate how synthetic-biology approaches can......-responsive biosensor systems that enable selective growth of cells only if they encode a ligand-specific importer. We developed such a synthetic selection system for thiamine pyrophosphate and mined soil and gut metagenomes for thiamine-uptake functions. We identified several members of a novel class of thiamine...

  10. Tips for Teachers Selecting Toys to Facilitate Social Interaction

    Science.gov (United States)

    Vail, Cynthia O.; Elmore, Shannon Renee

    2011-01-01

    Toy selection is an important role for early childhood teachers. This research-to-practice article describes what research tells us about how toys can affect the social interactions and communication of young children including those with developmental delays.

  11. Modeling for Colloid and Chelator Facilitated Nuclide Transport in Radioactive Waste Disposal System

    International Nuclear Information System (INIS)

    Lee, Youn Myoung; Jeong, Jong Tae

    2010-08-01

    A modeling study and development of a total system performance assessment (TSPA) program template, by which assessment of safety and performance for a radioactive waste repository with normal and/or abnormal nuclide release cases can be made has been developed. Colloid and chelator facilitated transport that is believed to result for faster nuclide transport in various mediabothinthegeosphereandbiospherehas been evaluated deterministically and probabilistically to demonstrate the capability of the template developed through this study. To this end colloid and chelator facilitated nuclide transport has been modeled rather strainghtforwardly with assumed data through this study by utilizing some powerful function offered by GoldSim. An evaluation in view of apparent influence of colloid and chelator on the nuclide transport in the various media in and around a repository system with data assumed are illustrated

  12. A Comparative Analysis of Trade Facilitation in Selected Regional and Bilateral Trade Agreement

    OpenAIRE

    Institute for International Trade

    2006-01-01

    This study compared the treatment of trade facilitation in four selected regional trade agreements, AFTA, APEC, SAFRA and PACER, and in one bilateral free trade agreement being the Australia-Singapore Free Trade Agreement (ASFTA), with a view to determining model trade facilitation principles and measures which may be instructive for developing country negotiations and policy makers.

  13. Mathematical Basis and Test Cases for Colloid-Facilitated Radionuclide Transport Modeling in GDSA-PFLOTRAN

    Energy Technology Data Exchange (ETDEWEB)

    Reimus, Paul William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-07-31

    This report provides documentation of the mathematical basis for a colloid-facilitated radionuclide transport modeling capability that can be incorporated into GDSA-PFLOTRAN. It also provides numerous test cases against which the modeling capability can be benchmarked once the model is implemented numerically in GDSA-PFLOTRAN. The test cases were run using a 1-D numerical model developed by the author, and the inputs and outputs from the 1-D model are provided in an electronic spreadsheet supplement to this report so that all cases can be reproduced in GDSA-PFLOTRAN, and the outputs can be directly compared with the 1-D model. The cases include examples of all potential scenarios in which colloid-facilitated transport could result in the accelerated transport of a radionuclide relative to its transport in the absence of colloids. Although it cannot be claimed that all the model features that are described in the mathematical basis were rigorously exercised in the test cases, the goal was to test the features that matter the most for colloid-facilitated transport; i.e., slow desorption of radionuclides from colloids, slow filtration of colloids, and equilibrium radionuclide partitioning to colloids that is strongly favored over partitioning to immobile surfaces, resulting in a substantial fraction of radionuclide mass being associated with mobile colloids.

  14. Colloid facilitated transport in fractured rocks: parameter estimation and comparison with experimental data

    International Nuclear Information System (INIS)

    Viswanthan, H.S.; Wolfsberg, A.V.; Reimus, P.W.; Ware, D.; Lu, G.

    2003-01-01

    Colloid-facilitated migration of plutonium in fractured rock has been implicated in both field and laboratory studies. Other reactive radionuclides may also experience enhanced mobility due to groundwater colloids. Model prediction of this process is necessary for assessment of contaminant boundaries in systems for which radionuclides are already in the groundwater and for performance assessment of potential repositories for radioactive waste. Therefore, a reactive transport model is developed and parameterized using results from controlled laboratory fracture column experiments. Silica, montmorillonite and clinoptilolite colloids are used in the experiments along with plutonium and Tritium. The goal of the numerical model is to identify and parameterize the physical and chemical processes that affect the colloid-facilitated transport of plutonium in the fractures. The parameters used in this model are similar in form to those that might be used in a field-scale transport model

  15. Carrier-facilitated transport of Cd(II) through a supported liquid membrane containing thiacalix[4]arene derivatives as ionophore

    International Nuclear Information System (INIS)

    Zaghbani, Asma; Tayeb, Rafik; Dhahbi, Mahmoud

    2009-01-01

    The feasibility of a facilitated transport process of cadmium ions through a SLM system incorporating new extractant agents, thiacalix[4]arenes, was studied. These molecules have sulfur atoms instead of usual methylene bridges. The chemical modification of the upper or the lower rim provides a great variety of supra molecules having different complexation ability and different conformational behaviour. The efficiency of the transport across the inner membrane organic liquid phase is shown to depend on the chemical (affinity) and structural (conformational states possible) parameters of these complexing molecules. In this work, two different thiacalix[4]arenes were selected as effective ionophore for the treatment of liquid media loaded in Cd(II). The results show that these thiacalix[4]arenes derivative ensure facilitated transport of cadmium cations through supported liquid membranes. Especially, the non-substituted thiacalix[4]arene can be considered as an effective extractant agent. The incidence of several parameters on transport efficiency such as pH of both aqueous solutions and carrier concentration was studied. The permeation of the species is due to a proton potential gradient (the driving force of the process) existing between the two opposite sides of the SLM. The initial flux, J, is found to be equal to 6.7.10 -7 mol.m -2 .s -1 , under optimal experimental conditions.

  16. Sensitivity analyses of a colloid-facilitated contaminant transport model for unsaturated heterogeneous soil conditions.

    Science.gov (United States)

    Périard, Yann; José Gumiere, Silvio; Rousseau, Alain N.; Caron, Jean

    2013-04-01

    Certain contaminants may travel faster through soils when they are sorbed to subsurface colloidal particles. Indeed, subsurface colloids may act as carriers of some contaminants accelerating their translocation through the soil into the water table. This phenomenon is known as colloid-facilitated contaminant transport. It plays a significant role in contaminant transport in soils and has been recognized as a source of groundwater contamination. From a mechanistic point of view, the attachment/detachment of the colloidal particles from the soil matrix or from the air-water interface and the straining process may modify the hydraulic properties of the porous media. Šimůnek et al. (2006) developed a model that can simulate the colloid-facilitated contaminant transport in variably saturated porous media. The model is based on the solution of a modified advection-dispersion equation that accounts for several processes, namely: straining, exclusion and attachement/detachement kinetics of colloids through the soil matrix. The solutions of these governing, partial differential equations are obtained using a standard Galerkin-type, linear finite element scheme, implemented in the HYDRUS-2D/3D software (Šimůnek et al., 2012). Modeling colloid transport through the soil and the interaction of colloids with the soil matrix and other contaminants is complex and requires the characterization of many model parameters. In practice, it is very difficult to assess actual transport parameter values, so they are often calibrated. However, before calibration, one needs to know which parameters have the greatest impact on output variables. This kind of information can be obtained through a sensitivity analysis of the model. The main objective of this work is to perform local and global sensitivity analyses of the colloid-facilitated contaminant transport module of HYDRUS. Sensitivity analysis was performed in two steps: (i) we applied a screening method based on Morris' elementary

  17. Structure and evolution of the plant cation diffusion facilitator family of ion transporters

    Directory of Open Access Journals (Sweden)

    Zanis Michael J

    2011-03-01

    Full Text Available Abstract Background Members of the cation diffusion facilitator (CDF family are integral membrane divalent cation transporters that transport metal ions out of the cytoplasm either into the extracellular space or into internal compartments such as the vacuole. The spectrum of cations known to be transported by proteins of the CDF family include Zn, Fe, Co, Cd, and Mn. Members of this family have been identified in prokaryotes, eukaryotes, and archaea, and in sequenced plant genomes. CDF families range in size from nine members in Selaginella moellendorffii to 19 members in Populus trichocarpa. Phylogenetic analysis suggests that the CDF family has expanded within plants, but a definitive plant CDF family phylogeny has not been constructed. Results Representative CDF members were annotated from diverse genomes across the Viridiplantae and Rhodophyta lineages and used to identify phylogenetic relationships within the CDF family. Bayesian phylogenetic analysis of CDF amino acid sequence data supports organizing land plant CDF family sequences into 7 groups. The origin of the 7 groups predates the emergence of land plants. Among these, 5 of the 7 groups are likely to have originated at the base of the tree of life, and 2 of 7 groups appear to be derived from a duplication event prior to or coincident with land plant evolution. Within land plants, local expansion continues within select groups, while several groups are strictly maintained as one gene copy per genome. Conclusions Defining the CDF gene family phylogeny contributes to our understanding of this family in several ways. First, when embarking upon functional studies of the members, defining primary groups improves the predictive power of functional assignment of orthologous/paralogous genes and aids in hypothesis generation. Second, defining groups will allow a group-specific sequence motif to be generated that will help define future CDF family sequences and aid in functional motif

  18. Heuristic Optimization Approach to Selecting a Transport Connection in City Public Transport

    Directory of Open Access Journals (Sweden)

    Kul’ka Jozef

    2017-02-01

    Full Text Available The article presents a heuristic optimization approach to select a suitable transport connection in the framework of a city public transport. This methodology was applied on a part of the public transport in Košice, because it is the second largest city in the Slovak Republic and its network of the public transport creates a complex transport system, which consists of three different transport modes, namely from the bus transport, tram transport and trolley-bus transport. This solution focused on examining the individual transport services and their interconnection in relevant interchange points.

  19. Fluctuation theorem for channel-facilitated membrane transport of interacting and noninteracting solutes.

    Science.gov (United States)

    Berezhkovskii, Alexander M; Bezrukov, Sergey M

    2008-05-15

    In this paper, we discuss the fluctuation theorem for channel-facilitated transport of solutes through a membrane separating two reservoirs. The transport is characterized by the probability, P(n)(t), that n solute particles have been transported from one reservoir to the other in time t. The fluctuation theorem establishes a relation between P(n)(t) and P-(n)(t): The ratio P(n)(t)/P-(n)(t) is independent of time and equal to exp(nbetaA), where betaA is the affinity measured in the thermal energy units. We show that the same fluctuation theorem is true for both single- and multichannel transport of noninteracting particles and particles which strongly repel each other.

  20. Methods for producing thin film charge selective transport layers

    Science.gov (United States)

    Hammond, Scott Ryan; Olson, Dana C.; van Hest, Marinus Franciscus Antonius Maria

    2018-01-02

    Methods for producing thin film charge selective transport layers are provided. In one embodiment, a method for forming a thin film charge selective transport layer comprises: providing a precursor solution comprising a metal containing reactive precursor material dissolved into a complexing solvent; depositing the precursor solution onto a surface of a substrate to form a film; and forming a charge selective transport layer on the substrate by annealing the film.

  1. The Methodology of Selecting the Transport Mode for Companies on the Slovak Transport Market

    Science.gov (United States)

    Černá, Lenka; Zitrický, Vladislav; Daniš, Jozef

    2017-03-01

    Transport volume in the Slovak Republic is growing continuously every year. This rising trend is influenced by the development of car industry and its suppliers. Slovak republic has also a geographic strategy position in middle Europe from the side of transport corridors (east-west and north-south). The development of transport volume in freight transport depends on the transport and business processes between the European Union and China and it is an opportunity for Slovak republic to obtain transit transport flows. In the Slovak Republic, road transport has a dominant position in the transport market. The volume of road transport has gradually increased over the past years. The increase of road transport is reflected on the highways and speed roads in regions which have higher economic potential. The increase of rail transport as seen on the main rail corridors is not as significant as in road transport. Trade globalization also has an influence on the increase of transport volume in intermodal transport. Predicted increase in transport volume for this transport mode is from 2,3 mil ton per year at present to 8 mil ton in the year 2020. Selection of transport mode and carrier is an important aspect for logistic management, because companies (customers) want to reduce the number of carriers which they trade and they create the system of several key carriers. Bigger transport volume and more qualitative transport service give a possibility to reduce transport costs. This trend is positive for carriers too, because the carriers can focus only on the selected customers and provide more qualitative services. The paper is focused on the selection of transport mode based on the proposed methodology. The aims of the paper are, definition of criteria which directly influence the selection of transport modes, determination of criteria based on the subjectively methods, creation of process for the selection of transport modes and practical application of proposed

  2. Characterization of putative multidrug resistance transporters of the major facilitator-superfamily expressed in Salmonella Typhi

    DEFF Research Database (Denmark)

    Shaheen, Aqsa; Ismat, Fouzia; Iqbal, Mazhar

    2015-01-01

    Multidrug resistance mediated by efflux pumps is a well-known phenomenon in infectious bacteria. Although much work has been carried out to characterize multidrug efflux pumps in Gram-negative and Gram-positive bacteria, such information is still lacking for many deadly pathogens. The aim...... of this study was to gain insight into the substrate specificity of previously uncharacterized transporters of Salmonella Typhi to identify their role in the development of multidrug resistance. S. Typhi genes encoding putative members of the major facilitator superfamily were cloned and expressed in the drug......-hypersensitive Escherichia coli strain KAM42, and tested for transport of 25 antibacterial compounds, including representative antibiotics of various classes, antiseptics, dyes and detergents. Of the 15 tested putative transporters, STY0901, STY2458 and STY4874 exhibited a drug-resistance phenotype. Among these, STY4874...

  3. Facilitated transport ceramic membranes for high-temperature gas cleanup. Final report, February 1990--April 1994

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, R.; Minford, E.; Damle, A.S.; Gangwal, S.K.; Hart, B.A.

    1994-04-01

    The objective of this program was to demonstrate the feasibility of developing high temperature, high pressure, facilitated transport ceramic membranes to control gaseous contaminants in Integrated Gasification Combined Cycle (IGCC) power generation systems. Meeting this objective requires that the contaminant gas H{sub 2}S be removed from an IGCC gas mixture without a substantial loss of the other gaseous components, specifically H{sub 2} and CH{sub 4}. As described above this requires consideration of other, nonconventional types of membranes. The solution evaluated in this program involved the use of facilitated transport membranes consisting of molten mixtures of alkali and alkaline earth carbonate salts immobilized in a microporous ceramic support. To accomplish this objective, Air Products and Chemicals, Inc., Golden Technologies Company Inc., and Research Triangle Institute worked together to develop and test high temperature facilitated membranes for the removal of H{sub 2}S from IGCC gas mixtures. Three basic experimental activities were pursued: (1) evaluation of the H{sub 2}S chemistry of a variety of alkali and alkaline earth carbonate salt mixtures; (2) development of microporous ceramic materials which were chemically and physically compatible with molten carbonate salt mixtures under IGCC conditions and which could function as a host to support a molten carbonate mixture and; (3) fabrication of molten carbonate/ceramic immobilized liquid membranes and evaluation of these membranes under conditions approximating those found in the intended application. Results of these activities are presented.

  4. Experimental and Numerical Investigations on Colloid-facilitated Plutonium Reactive Transport in Fractured Tuffaceous Rocks

    Science.gov (United States)

    Dai, Z.; Wolfsberg, A. V.; Zhu, L.; Reimus, P. W.

    2017-12-01

    Colloids have the potential to enhance mobility of strongly sorbing radionuclide contaminants in fractured rocks at underground nuclear test sites. This study presents an experimental and numerical investigation of colloid-facilitated plutonium reactive transport in fractured porous media for identifying plutonium sorption/filtration processes. The transport parameters for dispersion, diffusion, sorption, and filtration are estimated with inverse modeling for minimizing the least squares objective function of multicomponent concentration data from multiple transport experiments with the Shuffled Complex Evolution Metropolis (SCEM). Capitalizing on an unplanned experimental artifact that led to colloid formation and migration, we adopt a stepwise strategy to first interpret the data from each experiment separately and then to incorporate multiple experiments simultaneously to identify a suite of plutonium-colloid transport processes. Nonequilibrium or kinetic attachment and detachment of plutonium-colloid in fractures was clearly demonstrated and captured in the inverted modeling parameters along with estimates of the source plutonium fraction that formed plutonium-colloids. The results from this study provide valuable insights for understanding the transport mechanisms and environmental impacts of plutonium in fractured formations and groundwater aquifers.

  5. Facilitated transport of HNO3 through a supported liquid membrane containing a tertiary amine as carrier

    International Nuclear Information System (INIS)

    Cianetti, C.; Danesi, P.R.

    1983-01-01

    The facilitated transport of HNO 3 through a supported liquid membrane consisting of a porous polypropylene film containing a solution of trilaurylamine in diethylbenzene as carrier was studied as a function of the stirring speed of the aqueous solutions and the membrane composition. A physico-chemical model which takes into account diffusion through an aqueous boundary layer, a fast interfacial chemical reaction leading to the formation of a membrane soluble alkylammonium salt and diffusion through the membrane was proposed. In this way, equations were derived which describe how composition changes, occurring in the course of the permeation process, influence the membrane permeability. The experimental data were quantitatively explained by the derived equations. The results indicate that the monomeric form of the trilaurylammonium nitrate salt is the species which is mainly responsible for the acid transport through the membrane. The diffusion coefficient of the permeating species and the order of magnitude of the thickness of the aqueous boundary layer were evaluated. 8 figures

  6. Channel-facilitated molecular transport: The role of strength and spatial distribution of interactions

    Energy Technology Data Exchange (ETDEWEB)

    Uppulury, Karthik, E-mail: karthik.uppulury@gmail.com [Department of Chemistry, Texas Tech University, Lubbock, TX 79409 (United States); Kolomeisky, Anatoly B. [Department of Chemistry, Department of Chemical and Biomolecular Engineering, Center for Theoretical Biological Physics, Rice University, Houston, TX 77005 (United States)

    2016-12-20

    Highlights: • Molecular flux strongly depends on the strength of the molecule-pore interactions. • There exists an optimal molecule-pore interaction potential for maximal flux. • Volume of interactions depends inversely on the strength for maximal flux. • Stronger interactions need more number of attractive sites for maximal flux. • Channels with few special sites need more attractive sites for higher flux. - Abstract: Molecular transport across channels and pores is critically important for multiple natural and industrial processes. Recent advances in single-molecule techniques have allowed researchers to probe translocation through nanopores with unprecedented spatial and temporal resolution. However, our understanding of the mechanisms of channel-facilitated molecular transport is still not complete. We present a theoretical approach that investigates the role of molecular interactions in the transport through channels. It is based on the discrete-state stochastic analysis that provides a fully analytical description of this complex process. It is found that a spatial distribution of the interactions strongly influences the translocation dynamics. We predict that there is the optimal distribution that leads to the maximal flux through the channel. It is also argued that the channel transport depends on the strength of the molecule-pore interactions, on the shape of interaction potentials and on the relative contributions of entrance and diffusion processes in the system. These observations are discussed using simple physical-chemical arguments.

  7. Channel-facilitated molecular transport: The role of strength and spatial distribution of interactions

    International Nuclear Information System (INIS)

    Uppulury, Karthik; Kolomeisky, Anatoly B.

    2016-01-01

    Highlights: • Molecular flux strongly depends on the strength of the molecule-pore interactions. • There exists an optimal molecule-pore interaction potential for maximal flux. • Volume of interactions depends inversely on the strength for maximal flux. • Stronger interactions need more number of attractive sites for maximal flux. • Channels with few special sites need more attractive sites for higher flux. - Abstract: Molecular transport across channels and pores is critically important for multiple natural and industrial processes. Recent advances in single-molecule techniques have allowed researchers to probe translocation through nanopores with unprecedented spatial and temporal resolution. However, our understanding of the mechanisms of channel-facilitated molecular transport is still not complete. We present a theoretical approach that investigates the role of molecular interactions in the transport through channels. It is based on the discrete-state stochastic analysis that provides a fully analytical description of this complex process. It is found that a spatial distribution of the interactions strongly influences the translocation dynamics. We predict that there is the optimal distribution that leads to the maximal flux through the channel. It is also argued that the channel transport depends on the strength of the molecule-pore interactions, on the shape of interaction potentials and on the relative contributions of entrance and diffusion processes in the system. These observations are discussed using simple physical-chemical arguments.

  8. Uncertainty associated with selected environmental transport models

    International Nuclear Information System (INIS)

    Little, C.A.; Miller, C.W.

    1979-11-01

    A description is given of the capabilities of several models to predict accurately either pollutant concentrations in environmental media or radiological dose to human organs. The models are discussed in three sections: aquatic or surface water transport models, atmospheric transport models, and terrestrial and aquatic food chain models. Using data published primarily by model users, model predictions are compared to observations. This procedure is infeasible for food chain models and, therefore, the uncertainty embodied in the models input parameters, rather than the model output, is estimated. Aquatic transport models are divided into one-dimensional, longitudinal-vertical, and longitudinal-horizontal models. Several conclusions were made about the ability of the Gaussian plume atmospheric dispersion model to predict accurately downwind air concentrations from releases under several sets of conditions. It is concluded that no validation study has been conducted to test the predictions of either aquatic or terrestrial food chain models. Using the aquatic pathway from water to fish to an adult for 137 Cs as an example, a 95% one-tailed confidence limit interval for the predicted exposure is calculated by examining the distributions of the input parameters. Such an interval is found to be 16 times the value of the median exposure. A similar one-tailed limit for the air-grass-cow-milk-thyroid for 131 I and infants was 5.6 times the median dose. Of the three model types discussed in this report,the aquatic transport models appear to do the best job of predicting observed concentrations. However, this conclusion is based on many fewer aquatic validation data than were availaable for atmospheric model validation

  9. Poly(vinyl-alcohol)/poly(ethylene-glycol)/poly(ethylene-imine) blend membranes - structure and CO2 facilitated transport

    International Nuclear Information System (INIS)

    Ben Hamouda, S.; Quang, Trong Nguyen; Langevin, D.; Sadok, Roudeslic

    2010-01-01

    Poly(vinyl-alcohol) (PVA)/poly(ethylene-imine) (PEI)/poly(ethylene-glycol) (PEG) blend membranes were prepared by solution casting followed by solvent evaporation. The effects of the blend polymer composition on the membrane structure and CO 2 /N 2 permeation characteristics were investigated. IR spectroscopy evidenced strong hydrogen bonding interactions between amorphous PVA and PEI, and weaker interactions between PVA and PEG. DSC studies showed that PVA crystallization was partially inhibited by the interactions between amorphous PVA and PEI blend, in which PEG separated into nodules. The CO 2 permeability decreased with an increase in CO 2 partial pressure in feed gas, while the N 2 permeability remained constant. This result indicated that only CO 2 was transported by the facilitated transport mechanism. The CO 2 and N 2 permeabilities increased monotonically with the PEI content in the blend membranes, whereas the ideal selectivity of CO 2 to N 2 transport showed a maximum. When CO 2 is humidified, its permeability through the blend membranes is much higher than that of dry CO 2 , but the change in permeability due to the presence of humidity is reversible. (authors)

  10. Methodology for Mode Selection in Corridor Analysis of Freight Transportation

    OpenAIRE

    Kanafani, Adib

    1984-01-01

    The purpose of tins report is to outline a methodology for the analysis of mode selection in freight transportation. This methodology is intended to partake of transportation corridor analysts, a component of demand analysis that is part of a national transportation process. The methodological framework presented here provides a basis on which specific models and calculation procedures might be developed. It also provides a basis for the development of a data management system suitable for co...

  11. The Sodium Glucose Cotransporter SGLT1 Is an Extremely Efficient Facilitator of Passive Water Transport.

    Science.gov (United States)

    Erokhova, Liudmila; Horner, Andreas; Ollinger, Nicole; Siligan, Christine; Pohl, Peter

    2016-04-29

    The small intestine is void of aquaporins adept at facilitating vectorial water transport, and yet it reabsorbs ∼8 liters of fluid daily. Implications of the sodium glucose cotransporter SGLT1 in either pumping water or passively channeling water contrast with its reported water transporting capacity, which lags behind that of aquaporin-1 by 3 orders of magnitude. Here we overexpressed SGLT1 in MDCK cell monolayers and reconstituted the purified transporter into proteoliposomes. We observed the rate of osmotic proteoliposome deflation by light scattering. Fluorescence correlation spectroscopy served to assess (i) SGLT1 abundance in both vesicles and plasma membranes and (ii) flow-mediated dilution of an aqueous dye adjacent to the cell monolayer. Calculation of the unitary water channel permeability, pf, yielded similar values for cell and proteoliposome experiments. Neither the absence of glucose or Na(+), nor the lack of membrane voltage in vesicles, nor the directionality of water flow grossly altered pf Such weak dependence on protein conformation indicates that a water-impermeable occluded state (glucose and Na(+) in their binding pockets) lasts for only a minor fraction of the transport cycle or, alternatively, that occlusion of the substrate does not render the transporter water-impermeable as was suggested by computational studies of the bacterial homologue vSGLT. Although the similarity between the pf values of SGLT1 and aquaporin-1 makes a transcellular pathway plausible, it renders water pumping physiologically negligible because the passive flux would be orders of magnitude larger. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Parasitic nematodes modulate PIN-mediated auxin transport to facilitate infection.

    Directory of Open Access Journals (Sweden)

    Wim Grunewald

    2009-01-01

    Full Text Available Plant-parasitic nematodes are destructive plant pathogens that cause significant yield losses. They induce highly specialized feeding sites (NFS in infected plant roots from which they withdraw nutrients. In order to establish these NFS, it is thought that the nematodes manipulate the molecular and physiological pathways of their hosts. Evidence is accumulating that the plant signalling molecule auxin is involved in the initiation and development of the feeding sites of sedentary plant-parasitic nematodes. Intercellular transport of auxin is essential for various aspects of plant growth and development. Here, we analysed the spatial and temporal expression of PIN auxin transporters during the early events of NFS establishment using promoter-GUS/GFP fusion lines. Additionally, single and double pin mutants were used in infection studies to analyse the role of the different PIN proteins during cyst nematode infection. Based on our results, we postulate a model in which PIN1-mediated auxin transport is needed to deliver auxin to the initial syncytial cell, whereas PIN3 and PIN4 distribute the accumulated auxin laterally and are involved in the radial expansion of the NFS. Our data demonstrate that cyst nematodes are able to hijack the auxin distribution network in order to facilitate the infection process.

  13. Parasitic nematodes modulate PIN-mediated auxin transport to facilitate infection.

    Science.gov (United States)

    Grunewald, Wim; Cannoot, Bernard; Friml, Jirí; Gheysen, Godelieve

    2009-01-01

    Plant-parasitic nematodes are destructive plant pathogens that cause significant yield losses. They induce highly specialized feeding sites (NFS) in infected plant roots from which they withdraw nutrients. In order to establish these NFS, it is thought that the nematodes manipulate the molecular and physiological pathways of their hosts. Evidence is accumulating that the plant signalling molecule auxin is involved in the initiation and development of the feeding sites of sedentary plant-parasitic nematodes. Intercellular transport of auxin is essential for various aspects of plant growth and development. Here, we analysed the spatial and temporal expression of PIN auxin transporters during the early events of NFS establishment using promoter-GUS/GFP fusion lines. Additionally, single and double pin mutants were used in infection studies to analyse the role of the different PIN proteins during cyst nematode infection. Based on our results, we postulate a model in which PIN1-mediated auxin transport is needed to deliver auxin to the initial syncytial cell, whereas PIN3 and PIN4 distribute the accumulated auxin laterally and are involved in the radial expansion of the NFS. Our data demonstrate that cyst nematodes are able to hijack the auxin distribution network in order to facilitate the infection process.

  14. The prototypical proton-coupled oligopeptide transporter YdgR from Escherichia coli facilitates chloramphenicol uptake into bacterial cells

    DEFF Research Database (Denmark)

    Prabhala, Bala K; Aduri, Nanda G; Sharma, Neha

    2018-01-01

    . However, to date no report exists on any specific transport protein that facilitates Cam uptake. The proton-coupled oligopeptide transporter (POT) YdgR from Escherichia coli is a prototypical member of the POT family, functioning in proton-coupled uptake of di- and tripeptides. By following bacterial...

  15. Development of facilitated transport membranes for the separation of olefins from gas streams; Entwicklung von Carriermembranen zur Olefinabtrennung aus Gasstroemen

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, J. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Chemie

    2001-07-01

    The current work is concerned with the development of highly selective facilitated transport membranes for olefin/paraffin separation. Adsorption measurements with 7 silver salts showed that silver-perchlorate was the most promising carrier material. This carrier was embedded into two different commercial available polyetherblockamides - Pebax trademark 4011 and Pebax trademark 2533 with up to 41 wt.-% of silver ions. The solubility of the carrier in polymer and the influence of humidity on the separation characteristics of the membranes were studied in detail. The aging of the membrane samples was investigated as well. A composite membrane with a top layer of Pebax trademark 2533/silver-perchlorate showed the best performance. Ethylene permeabilities in the range of 0.1 to 0.4 m{sup 3}/m{sup 2} h bar and gas mixture selectivities of 110 to 400 were measured with an humidified equimolar gas mixture of ethylene and ethane. Best results were obtained with membranes manufactured from proposely aging coating solutions and a sub-surface-structure. These membranes showed a permeability coefficient up to 1000 Barrer for ethylene with a gas mixture selectivity of 400. (orig.)

  16. Harmonize input selection for sediment transport prediction

    Science.gov (United States)

    Afan, Haitham Abdulmohsin; Keshtegar, Behrooz; Mohtar, Wan Hanna Melini Wan; El-Shafie, Ahmed

    2017-09-01

    In this paper, three modeling approaches using a Neural Network (NN), Response Surface Method (RSM) and response surface method basis Global Harmony Search (GHS) are applied to predict the daily time series suspended sediment load. Generally, the input variables for forecasting the suspended sediment load are manually selected based on the maximum correlations of input variables in the modeling approaches based on NN and RSM. The RSM is improved to select the input variables by using the errors terms of training data based on the GHS, namely as response surface method and global harmony search (RSM-GHS) modeling method. The second-order polynomial function with cross terms is applied to calibrate the time series suspended sediment load with three, four and five input variables in the proposed RSM-GHS. The linear, square and cross corrections of twenty input variables of antecedent values of suspended sediment load and water discharge are investigated to achieve the best predictions of the RSM based on the GHS method. The performances of the NN, RSM and proposed RSM-GHS including both accuracy and simplicity are compared through several comparative predicted and error statistics. The results illustrated that the proposed RSM-GHS is as uncomplicated as the RSM but performed better, where fewer errors and better correlation was observed (R = 0.95, MAE = 18.09 (ton/day), RMSE = 25.16 (ton/day)) compared to the ANN (R = 0.91, MAE = 20.17 (ton/day), RMSE = 33.09 (ton/day)) and RSM (R = 0.91, MAE = 20.06 (ton/day), RMSE = 31.92 (ton/day)) for all types of input variables.

  17. Colloid-Facilitated Transport of Cations in an Unsaturated Fractured Soil Under Transient Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, Joseph [Univ. of Colorado, Boulder, CO (United States)

    2015-01-31

    Rainfall experiments were conducted using intact soil cores and an instrumented soil pedon to examine the effect of physical heterogeneity and rainfall characteristics on the mobilization of colloids, organic matter, cesium, and strontium in a fractured soil. To measure the spatial variability of infiltration of colloids and contaminants, samples were collected through a 19-port grid placed below the soil core in laboratory study and in 27 samplers at multiple depths in the soil pedon in the field study. Cesium and strontium were applied to the soil cores and the soil pedon prior to mobilization experiments. Rainwater solutions of multiple ionic strengths and organic matter concentrations were applied to the soil cores and soil pedon to mobilize in situ colloids, cesium, and strontium. The mobilization of colloids and metal cations occurred through preferential flow paths in the soil cores. Compared to steady rainfall, greater amounts of colloids were mobilized during rainfall interrupted by pauses, which indicates that the supply of colloids to be mobilized was replenished during the pauses. A maximum in the amount of mobilized colloids were mobilized during a rainfall following a pause of 2.5 d. Pauses of shorter or longer duration resulted in less colloid mobilization. Freeze-thaw cycles, a transient condition in winter, enhanced colloid mobilization and colloid-facilitated transport of cesium and strontium in the soil cores. The exchange of solutes between the soil matrix and macropores caused a hysteretic mobilization of colloids, cesium, and strontium during changes in ionic strength. Colloid-facilitated mobilization of cesium and strontium was important at low ionic strength in fractures where slow flow allowed greater exchange of flow between the fractures and the surrounding matrix. The release of cesium and strontium by cation exchange occurred at high ionic strength in fractures where there is a little exchange of pore water with the surrounding matrix

  18. Effect of chemical and physical heterogeneities on colloid-facilitated cesium transport

    Science.gov (United States)

    Rod, Kenton; Um, Wooyong; Chun, Jaehun; Wu, Ning; Yin, Xialong; Wang, Guohui; Neeves, Keith

    2018-06-01

    A set of column experiments was conducted to investigate the chemical and physical heterogeneity effect on colloid facilitated transport under slow pore velocity conditions. Pore velocities were kept below 100 cm d-1 for all experiments. Glass beads were packed into columns establishing four different conditions: 1) homogeneous, 2) mixed physical heterogeneity, 3) sequentially layered physical heterogeneity, and 4) chemical heterogeneity. The homogeneous column was packed with glass beads (diameter 500-600 μm), and physical heterogeneities were created by sequential layering or mixing two sizes of glass bead (500-600 μm and 300-400 μm). A chemical heterogeneity was created using 25% of the glass beads coated with hydrophobic molecules (1H-1H-2H-2H-perfluorooctyltrichlorosilane) mixed with 75% pristine glass beads (all 500-600 μm). Input solution with 0.5 mM CsI and 50 mg L-1 colloids (1-μm diameter SiO2) was pulsed into columns under saturated conditions. The physical heterogeneity in the packed glass beads retarded the transport of colloids compared to homogeneous (R = 25.0), but showed only slight differences between sequentially layered (R = 60.7) and mixed heterogeneity(R = 62.4). The column with the chemical, hydrophobic/hydrophilic, heterogeneity removed most of the colloids from the input solution. All column conditions stripped Cs from colloids onto the column matrix of packed glass beads.

  19. Model-independent plot of dynamic PET data facilitates data interpretation and model selection.

    Science.gov (United States)

    Munk, Ole Lajord

    2012-02-21

    When testing new PET radiotracers or new applications of existing tracers, the blood-tissue exchange and the metabolism need to be examined. However, conventional plots of measured time-activity curves from dynamic PET do not reveal the inherent kinetic information. A novel model-independent volume-influx plot (vi-plot) was developed and validated. The new vi-plot shows the time course of the instantaneous distribution volume and the instantaneous influx rate. The vi-plot visualises physiological information that facilitates model selection and it reveals when a quasi-steady state is reached, which is a prerequisite for the use of the graphical analyses by Logan and Gjedde-Patlak. Both axes of the vi-plot have direct physiological interpretation, and the plot shows kinetic parameter in close agreement with estimates obtained by non-linear kinetic modelling. The vi-plot is equally useful for analyses of PET data based on a plasma input function or a reference region input function. The vi-plot is a model-independent and informative plot for data exploration that facilitates the selection of an appropriate method for data analysis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Route selection for the transport of hazardous materials

    Energy Technology Data Exchange (ETDEWEB)

    Seiler, F A

    1988-12-01

    The factors governing the risk-weighted selection of routes for transport of hazardous materials are analyzed. Starting from a formulation for the total risk of these transports that assumes complete information, approximations for the more realistic case of partial and uncertain information are discussed. These approximations involve well-known risk assessment techniques and mathematical methods; among the latter, Monte Carlo calculations hold the most promise. The actual route selection is based on an index of total societal cost, evaluated for a set of potential routes. (author)

  1. Facilitated transport of titanium dioxide nanoparticles by humic substances in saturated porous media under acidic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ruichang [Chinese Academy of Sciences, Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science (China); Zhang, Haibo; Tu, Chen; Hu, Xuefeng; Li, Lianzhen [Chinese Academy of Sciences, Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (China); Luo, Yongming, E-mail: ymluo@yic.ac.cn; Christie, Peter [Chinese Academy of Sciences, Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science (China)

    2015-04-15

    The transport behavior of titanium dioxide nanoparticles (TiO{sub 2} NPs, 30 nm in diameter) was studied in well-defined porous media composed of clean quartz sand over a range of solution chemistry under acidic conditions. Transport of TiO{sub 2} NPs was dramatically enhanced by humic substances (HS) at acidic pH (4.0, 5.0 and 6.0), even at a low HS concentration of 0.5 mg L{sup −1}. Facilitated transport of TiO{sub 2} NPs was likely attributable to the increased stability of TiO{sub 2} NPs and repulsive interaction between TiO{sub 2} NPs and quartz sands due to the adsorbed HS. The mobility of TiO{sub 2} NPs was also increased with increasing pH from 4.0 to 6.0. Although transport of TiO{sub 2} NPs was insensitive to low ionic strength, it was significantly inhibited by high concentrations of NaCl and CaCl{sub 2}. In addition, calculated Derjaguin–Landau–Verwey–Overbeek (DLVO) interaction energy indicated that high energy barriers were responsible for the high mobility of TiO{sub 2} NPs, while the secondary energy minimum could play an important role in the retention of TiO{sub 2} NPs at 100 mmol L{sup −1} NaCl. Straining and gravitational settlement of larger TiO{sub 2} NPs aggregates at 1 mg L{sup −1} HS, pH 5.0, and 2 mmol L{sup −1} CaCl{sub 2} could be responsible for the significant retention even in the presence of high energy barriers. Moreover, more favorable interaction between approaching TiO{sub 2} NPs and TiO{sub 2} NPs that had been already deposited on the collector resulted in a ripening-shape breakthrough curve at 2 mmol L{sup −1} CaCl{sub 2}. Overall, a combination of mechanisms including DLVO-type force, straining, and physical filtration was involved in the retention of TiO{sub 2} NPs over the range of solution chemistry examined in this study.

  2. Expression, purification, and functional characterization of the insulin-responsive facilitative glucose transporter GLUT4.

    Science.gov (United States)

    Kraft, Thomas E; Hresko, Richard C; Hruz, Paul W

    2015-12-01

    The insulin-responsive facilitative glucose transporter GLUT4 is of fundamental importance for maintenance of glucose homeostasis. Despite intensive effort, the ability to express and purify sufficient quantities of structurally and functionally intact protein for biophysical analysis has previously been exceedingly difficult. We report here the development of novel methods to express, purify, and functionally reconstitute GLUT4 into detergent micelles and proteoliposomes. Rat GLUT4 containing FLAG and His tags at the amino and carboxy termini, respectively, was engineered and stably transfected into HEK-293 cells. Overexpression in suspension culture yielded over 1.5 mg of protein per liter of culture. Systematic screening of detergent solubilized GLUT4-GFP fusion protein via fluorescent-detection size exclusion chromatography identified lauryl maltose neopentyl glycol (LMNG) as highly effective for isolating monomeric GLUT4 micelles. Preservation of structural integrity and ligand binding was demonstrated via quenching of tryptophan fluorescence and competition of ATB-BMPA photolabeling by cytochalasin B. GLUT4 was reconstituted into lipid nanodiscs and proper folding was confirmed. Reconstitution of purified GLUT4 with amphipol A8-35 stabilized the transporter at elevated temperatures for extended periods of time. Functional activity of purified GLUT4 was confirmed by reconstitution of LMNG-purified GLUT4 into proteoliposomes and measurement of saturable uptake of D-glucose over L-glucose. Taken together, these data validate the development of an efficient means to generate milligram quantities of stable and functionally intact GLUT4 that is suitable for a wide array of biochemical and biophysical analyses. © 2015 The Protein Society.

  3. Directed Evolution of Membrane Transport Using Synthetic Selections

    DEFF Research Database (Denmark)

    Bali, Anne Pihl; Genee, Hans J.; Sommer, Morten O. A.

    2018-01-01

    systems that enable selective growth of E. coli cells only if they functionally express an importer that is specific to the biosensor ligand. Using this system in a directed evolution framework, we successfully engineer the specificity of nicotinamide riboside transporters, PnuC, to accept thiamine...

  4. Engineered Dwarf Male-Sterile Rice: A Promising Genetic Tool for Facilitating Recurrent Selection in Rice.

    Science.gov (United States)

    Ansari, Afsana; Wang, Chunlian; Wang, Jian; Wang, Fujun; Liu, Piqing; Gao, Ying; Tang, Yongchao; Zhao, Kaijun

    2017-01-01

    Rice is a crop feeding half of the world's population. With the continuous raise of yield potential via genetic improvement, rice breeding has entered an era where multiple genes conferring complex traits must be efficiently manipulated to increase rice yield further. Recurrent selection is a sound strategy for manipulating multiple genes and it has been successfully performed in allogamous crops. However, the difficulties in emasculation and hand pollination had obstructed efficient use of recurrent selection in autogamous rice. Here, we report development of the dwarf male-sterile rice that can facilitate recurrent selection in rice breeding. We adopted RNAi technology to synergistically regulate rice plant height and male fertility to create the dwarf male-sterile rice. The RNAi construct pTCK-EGGE, targeting the OsGA20ox2 and OsEAT1 genes, was constructed and used to transform rice via Agrobacterium -mediated transformation. The transgenic T0 plants showing largely reduced plant height and complete male-sterile phenotypes were designated as the dwarf male-sterile plants. Progenies of the dwarf male-sterile plants were obtained by pollinating them with pollens from the wild-type. In the T1 and T2 populations, half of the plants were still dwarf male-sterile; the other half displayed normal plant height and male fertility which were designated as tall and male-fertile plants. The tall and male-fertile plants are transgene-free and can be self-pollinated to generate new varieties. Since emasculation and hand pollination for dwarf male-sterile rice plants is no longer needed, the dwarf male-sterile rice can be used to perform recurrent selection in rice. A dwarf male-sterile rice-based recurrent selection model has been proposed.

  5. Sources of transportation expertise by selected technical areas

    International Nuclear Information System (INIS)

    1987-01-01

    The US Department of Energy (DOE), Office of Civilian Radioactive Waste Management (OCRWM) has assigned components of its Waste Transportation Program to three of the DOE Operations offices. The DOE Oak Ridge Operations Office (ORO) is responsible for the transportation operations design, development, acquisition, testing, implementation, and program management, including the equipment, facilities, and services of the transportation system. Within ORO, the OCRWM transportation component is assigned to the Transportation Operations Project Office (TOPO). The specific activities involved in the ORO/TOPO include procurement, operational testing, inspection, logistics, interfaces, maintenance, management and improvements, and system operation. Oak Ridge Associated Universities (ORAU) has developed (and will maintain and enhance) a data base of sources of transportation expertise in selected technical areas for ORO. The data base includes individuals and organizations who have indicated that they have capabilities and interest in assisting ORO in the design, development, implementation, and management of the OCRWM transportation system. This assistance might be in the form of consulting or subcontract work and/or participation in peer review panels, technical evaluation committees, workshops, advisory groups, etc. This initial project was completed in the four month period of January 30, 1987 through May 31, 1987

  6. Facilitated transport of Cu with hydroxyapatite nanoparticles in saturated sand: Effects of solution ionic strength and composition

    Science.gov (United States)

    Column experiments were conducted to investigate the facilitated transport of Cu in association with hydroxyapatite nanoparticles (nHAP) in water-saturated quartz sand at different solution concentrations of NaCl (0 to 100 mM) or CaCl2 (0.1 to 1.0 mM). The experimental breakthrough curves and retent...

  7. Use of GIS technologies to facilitate the transportation project programming process.

    Science.gov (United States)

    2008-05-01

    Transportation project programming in a transportation agency is a process of matching : potential projects with available funds to accomplish the agencys mission and goals of a : given period of time. Result of this process is normally a transpor...

  8. Colloid-Facilitated Radionuclide Transport: Current State of Knowledge from a Nuclear Waste Repository Risk Assessment Perspective

    International Nuclear Information System (INIS)

    Reimus, Paul William; Zavarin, Mavrik; Wang, Yifeng

    2017-01-01

    This report provides an overview of the current state of knowledge of colloid-facilitated radionuclide transport from a nuclear waste repository risk assessment perspective. It draws on work that has been conducted over the past 3 decades, although there is considerable emphasis given to work that has been performed over the past 3-5 years as part of the DOE Used Fuel Disposition Campaign. The timing of this report coincides with the completion of a 3-year DOE membership in the Colloids Formation and Migration (CFM) partnership, an international collaboration of scientists studying colloid-facilitated transport of radionuclides at both the laboratory and field-scales in a fractured crystalline granodiorite at the Grimsel Test Site in Switzerland. This Underground Research Laboratory has hosted the most extensive and carefully-controlled set of colloid-facilitated solute transport experiments that have ever been conducted in an in-situ setting, and a summary of the results to date from these efforts, as they relate to transport over long time and distance scales, is provided in Chapter 3 of this report.

  9. Colloid-Facilitated Radionuclide Transport: Current State of Knowledge from a Nuclear Waste Repository Risk Assessment Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Reimus, Paul William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Zavarin, Mavrik [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wang, Yifeng [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-01-25

    This report provides an overview of the current state of knowledge of colloid-facilitated radionuclide transport from a nuclear waste repository risk assessment perspective. It draws on work that has been conducted over the past 3 decades, although there is considerable emphasis given to work that has been performed over the past 3-5 years as part of the DOE Used Fuel Disposition Campaign. The timing of this report coincides with the completion of a 3-year DOE membership in the Colloids Formation and Migration (CFM) partnership, an international collaboration of scientists studying colloid-facilitated transport of radionuclides at both the laboratory and field-scales in a fractured crystalline granodiorite at the Grimsel Test Site in Switzerland. This Underground Research Laboratory has hosted the most extensive and carefully-controlled set of colloid-facilitated solute transport experiments that have ever been conducted in an in-situ setting, and a summary of the results to date from these efforts, as they relate to transport over long time and distance scales, is provided in Chapter 3 of this report.

  10. Peculiarities of the radioactive particles transport phenomena in the facilitated diffusion processes

    International Nuclear Information System (INIS)

    Gavryushenko, D.A.; Sisojev, V.M.; Cherevko, K.V.; Vlasenko, T.S.

    2017-01-01

    The work is devoted to the up to date problem that is the description of the radioactive particle diffusion processes. One of the aims of the present study is to estimate the effects caused by the irradiation of the liquid systems on the ongoing transport processes. That can allow predicting the behavior of the liquid systems in the presence of the radioactive sources. The main objective of the present work is studying the radioactive particles diffusion phenomena with the possible facilitated diffusion processes being considered. The phenomena are studied based on the fundamental relations of the nonequilibrium statistical thermodynamics. The diffusive flows are evaluated with the special attention given to the accounting of the entropy effects due to the appearance of the new radioactive particles in the system. The developed approach is used to estimate the diffusive flow of the radioactive particles for the case of the plane-parallel pore with the semi-transparent walls. The choice of a model can be justified as it might be used to describe the production of the radioactive contaminated water when the radionuclide face the diffusion process after being washed from the radioactive wastes and the rests of the nuclear fuel. Within the suggested model it is shown that the diffusion coefficient depends on the structural properties of the liquid systems that might be changed under the influence of the irradiation. The obtained equations for calculating the diffusive flows show the definite stabilizing effect in respect to the concentration difference in between the boundaries of the plane-parallel pore. It leads to the decreased changes of the diffusive flow when the concentrations of the radioactive particles at the boundaries are changed in comparison with those observed for the constant diffusion coefficient. The observed behavior for the ideal solution model is explained by the entropy effects. The qualitative analysis of the possible influence of the changes in

  11. LONG-TERM COLLOID MOBILIZATION AND COLLOID-FACILITATED TRANSPORT OF RADIONUCLIDES IN A SEMI-ARID VADOSE ZONE

    Energy Technology Data Exchange (ETDEWEB)

    Markus Flury; James B. Harsh; Fred Zhang; Glendon W. Gee; Earl D. Mattson; Peter C. L

    2012-08-01

    The main purpose of this project was to improve the fundamental mechanistic understanding and quantification of long-term colloid mobilization and colloid-facilitated transport of radionuclides in the vadose zone, with special emphasis on the semi-arid Hanford site. While we focused some of the experiments on hydrogeological and geochemical conditions of the Hanford site, many of our results apply to colloid and colloid-facilitated transport in general. Specific objectives were (1) to determine the mechanisms of colloid mobilization and colloid-facilitated radionuclide transport in undisturbed Hanford sediments under unsaturated flow, (2) to quantify in situ colloid mobilization and colloid-facilitated radionuclidetransport from Hanford sediments under field conditions, and (3) to develop a field-scale conceptual and numerical model for colloid mobilization and transport at the Hanford vadose zone, and use that model to predict long-term colloid and colloid- facilitated radionuclide transport. To achieve these goals and objectives, we have used a combination of experimental, theoretical, and numerical methods at different spatial scales, ranging from microscopic investigationsof single particle attachment and detachment to larger-scale field experiments using outdoor lysimeters at the Hanford site. Microscopic and single particle investigations provided fundamental insight into mechanisms of colloid interactions with the air-water interface. We could show that a moving air water interface (such as a moving water front during infiltration and drainage) is very effective in removing and mobilizing particles from a stationary surface. We further demonstrated that it is particularly the advancing air-water interface which is mainly responsible for colloid mobilization. Forces acting on the colloids calculated from theory corroborated our experimental results, and confirm that the detachment forces (surface tension forces) during the advancing air-water interface

  12. Selection of organic chemicals for subsurface transport. Subsurface transport program interaction seminar series. Summary

    International Nuclear Information System (INIS)

    Zachara, J.M.; Wobber, F.J.

    1984-11-01

    Model compounds are finding increasing use in environmental research. These individual compounds are selected as surrogates of important contaminants present in energy/defense wastes and their leachates and are used separately or as mixtures in research to define the anticipated or ''model'' environmental behavior of key waste components and to probe important physicochemical mechanisms involved in transport and fate. A seminar was held in Germantown, Maryland, April 24-25, 1984 to discuss the nature of model organic compounds being used for subsurface transport research. The seminar included participants experienced in the fields of environmental chemistry, microbiology, geohydrology, biology, and analytic chemistry. The objectives of the seminar were two-fold: (1) to review the rationale for the selection of organic compounds adopted by research groups working on the subsurface transport of organics, and (2) to evaluate the use of individual compounds to bracket the behavior of compound classes and compound constructs to approximate the behavior of complex organic mixtures

  13. Rate and mechanism of facilitated americium(III) transport through a supported liquid membrane containing a bifunctional organophosphorus mobile carrier

    International Nuclear Information System (INIS)

    Danesi, P.R.; Horwitz, E.P.; Rickert, P.G.

    1983-01-01

    The facilitated transport of Am(III) from aqueous nitrate solutions to formic acid aqueous solutions through a supported liquid membrane (SLM) is described. The supported liquid membrane consists of a solution of a new (carbamoylmethyl)phosphine oxide in diethylbenzene (DEB) absorbed into a 48 μm thick microporous polypropylene film. The transport mechanism consists of a diffusion process through an aqueous diffusion film, a fast interfacial chemical reaction, and diffusion through the membrane itself. Equations describing the rate of transport are derived. They correlate the membrane permeability coefficient to diffusional parameters and to the chemical composition of the system. Different rate-controlling processes are shown to control the membrane permeability when the composition of the system is varied and as long as the transport occurs. The experimental data are quantitatively explained with the derived equations. The diffusion coefficient of the permeating species and the equilibrium constant of the fast interfacial reactions are evaluated. 13 figures, 1 table

  14. Hsp70 facilitates trans-membrane transport of bacterial ADP-ribosylating toxins into the cytosol of mammalian cells.

    Science.gov (United States)

    Ernst, Katharina; Schmid, Johannes; Beck, Matthias; Hägele, Marlen; Hohwieler, Meike; Hauff, Patricia; Ückert, Anna Katharina; Anastasia, Anna; Fauler, Michael; Jank, Thomas; Aktories, Klaus; Popoff, Michel R; Schiene-Fischer, Cordelia; Kleger, Alexander; Müller, Martin; Frick, Manfred; Barth, Holger

    2017-06-02

    Binary enterotoxins Clostridium (C.) botulinum C2 toxin, C. perfringens iota toxin and C. difficile toxin CDT are composed of a transport (B) and a separate non-linked enzyme (A) component. Their B-components mediate endocytic uptake into mammalian cells and subsequently transport of the A-components from acidic endosomes into the cytosol, where the latter ADP-ribosylate G-actin resulting in cell rounding and cell death causing clinical symptoms. Protein folding enzymes, including Hsp90 and peptidyl-prolyl cis/trans isomerases facilitate transport of the A-components across endosomal membranes. Here, we identified Hsp70 as a novel host cell factor specifically interacting with A-components of C2, iota and CDT toxins to facilitate their transport into the cell cytosol. Pharmacological Hsp70-inhibition specifically prevented pH-dependent trans-membrane transport of A-components into the cytosol thereby protecting living cells and stem cell-derived human miniguts from intoxication. Thus, Hsp70-inhibition might lead to development of novel therapeutic strategies to treat diseases associated with bacterial ADP-ribosylating toxins.

  15. Differential bacterial capture and transport preferences facilitate co-growth on dietary xylan in the human gut

    DEFF Research Database (Denmark)

    Leth, Maria Louise; Ejby, Morten; Workman, Christopher

    2018-01-01

    Metabolism of dietary glycans is pivotal in shaping the human gut microbiota. However, the mechanisms that promote competition for glycans among gut commensals remain unclear. Roseburia intestinalis, an abundant butyrate-producing Firmicute, is a key degrader of the major dietary fibre xylan...... of capture and transport preferences as a possible strategy to facilitate co-growth on abundant dietary fibres and may offer a unique route to manipulate the microbiota based on glycan transport preferences in therapeutic interventions to boost distinct taxa....

  16. Sample selection and taste correlation in discrete choice transport modelling

    DEFF Research Database (Denmark)

    Mabit, Stefan Lindhard

    2008-01-01

    explain counterintuitive results in value of travel time estimation. However, the results also point at the difficulty of finding suitable instruments for the selection mechanism. Taste heterogeneity is another important aspect of discrete choice modelling. Mixed logit models are designed to capture...... the question for a broader class of models. It is shown that the original result may be somewhat generalised. Another question investigated is whether mode choice operates as a self-selection mechanism in the estimation of the value of travel time. The results show that self-selection can at least partly...... of taste correlation in willingness-to-pay estimation are presented. The first contribution addresses how to incorporate taste correlation in the estimation of the value of travel time for public transport. Given a limited dataset the approach taken is to use theory on the value of travel time as guidance...

  17. Facilitated Anion Transport Induces Hyperpolarization of the Cell Membrane That Triggers Differentiation and Cell Death in Cancer Stem Cells.

    Science.gov (United States)

    Soto-Cerrato, Vanessa; Manuel-Manresa, Pilar; Hernando, Elsa; Calabuig-Fariñas, Silvia; Martínez-Romero, Alicia; Fernández-Dueñas, Víctor; Sahlholm, Kristoffer; Knöpfel, Thomas; García-Valverde, María; Rodilla, Ananda M; Jantus-Lewintre, Eloisa; Farràs, Rosa; Ciruela, Francisco; Pérez-Tomás, Ricardo; Quesada, Roberto

    2015-12-23

    Facilitated anion transport potentially represents a powerful tool to modulate various cellular functions. However, research into the biological effects of small molecule anionophores is still at an early stage. Here we have used two potent anionophore molecules inspired in the structure of marine metabolites tambjamines to gain insight into the effect induced by these compounds at the cellular level. We show how active anionophores, capable of facilitating the transmembrane transport of chloride and bicarbonate in model phospholipid liposomes, induce acidification of the cytosol and hyperpolarization of plasma cell membranes. We demonstrate how this combined effect can be used against cancer stem cells (CSCs). Hyperpolarization of cell membrane induces cell differentiation and loss of stemness of CSCs leading to effective elimination of this cancer cell subpopulation.

  18. Intelligent transportation systems at international borders : a cross-cutting study : facilitating trade and enhancing transportation safety

    Science.gov (United States)

    2001-04-01

    The International Border Clearance (IBC) program was initiated under the provisions of the Intermodal Surface Transportation Efficiency Act (ISTEA) of 1991. The program was originally conceived as a means to test the feasibility of utilizing Intellig...

  19. Serial transverse enteroplasty to facilitate enteral autonomy in selected children with short bowel syndrome.

    Science.gov (United States)

    Wester, T; Borg, H; Naji, H; Stenström, P; Westbacke, G; Lilja, H E

    2014-09-01

    Serial transverse enteroplasty (STEP) was first described in 2003 as a method for lengthening and tapering of the bowel in short bowel syndrome. The aim of this multicentre study was to review the outcome of a Swedish cohort of children who underwent STEP. All children who had a STEP procedure at one of the four centres of paediatric surgery in Sweden between September 2005 and January 2013 were included in this observational cohort study. Demographic details, and data from the time of STEP and at follow-up were collected from the case records and analysed. Twelve patients had a total of 16 STEP procedures; four children underwent a second STEP. The first STEP was performed at a median age of 5·8 (range 0·9-19·0) months. There was no death at a median follow-up of 37·2 (range 3·0-87·5) months and no child had small bowel transplantation. Seven of the 12 children were weaned from parenteral nutrition at a median of 19·5 (range 2·3-42·9) months after STEP. STEP is a useful procedure for selected patients with short bowel syndrome and seems to facilitate weaning from parenteral nutrition. At mid-term follow-up a majority of the children had achieved enteral autonomy. The study is limited by the small sample size and lack of a control group. © 2014 The Authors. BJS published by John Wiley & Sons Ltd on behalf of BJS Society Ltd.

  20. Facilitated transport of hydrophilic salts by mixtures of anion and cation carriers and by ditopic carriers

    NARCIS (Netherlands)

    Chrisstoffels, L.A.J.; de Jong, Feike; Reinhoudt, David; Sivelli, Stefano; Gazzola, Licia; Casnati, Alessandro; Ungaro, Rocco

    1999-01-01

    Anion transfer to the membrane phase affects the extraction efficiency of salt transport by cation carriers 1 and 3. Addition of anion receptors 5 or 6 to cation carriers 1, 3, or 4 in the membrane phase enhances the transport of salts under conditions in which the cation carriers alone do not

  1. Considerations in the selection of transport modes for spent nuclear fuel shipments

    International Nuclear Information System (INIS)

    Daling, P.M.; McNair, G.W.; Andrews, W.B.

    1985-07-01

    This paper discusses the factors associated with selecting a particular transport mode for spent fuel shipments. These factors include transportation costs, economics of potential transportation accidents, risk/safety of spent fuel transportation, routing alternatives, shipping cask handling capabilities, and shipping cask availability. Data needed to estimate transportation costs and risks are presented and discussed. The remaining factors are discussed qualitatively and can be used as guidance for selecting a particular transport mode. 15 refs., 3 tabs

  2. Convective transport of highly plasma protein bound drugs facilitates direct penetration into deep tissues after topical application

    Science.gov (United States)

    Dancik, Yuri; Anissimov, Yuri G; Jepps, Owen G; Roberts, Michael S

    2012-01-01

    AIMS To relate the varying dermal, subcutaneous and muscle microdialysate concentrations found in man after topical application to the nature of the drug applied and to the underlying physiology. METHODS We developed a physiologically based pharmacokinetic model in which transport to deeper tissues was determined by tissue diffusion, blood, lymphatic and intersitial flow transport and drug properties. The model was applied to interpret published human microdialysis data, estimated in vitro dermal diffusion and protein binding affinity of drugs that have been previously applied topically in vivo and measured in deep cutaneous tissues over time. RESULTS Deeper tissue microdialysis concentrations for various drugs in vivo vary widely. Here, we show that carriage by the blood to the deeper tissues below topical application sites facilitates the transport of highly plasma protein bound drugs that penetrate the skin, leading to rapid and significant concentrations in those tissues. Hence, the fractional concentration for the highly plasma protein bound diclofenac in deeper tissues is 0.79 times that in a probe 4.5 mm below a superficial probe whereas the corresponding fractional concentration for the poorly protein bound nicotine is 0.02. Their corresponding estimated in vivo lag times for appearance of the drugs in the deeper probes were 1.1 min for diclofenac and 30 min for nicotine. CONCLUSIONS Poorly plasma protein bound drugs are mainly transported to deeper tissues after topical application by tissue diffusion whereas the transport of highly plasma protein bound drugs is additionally facilitated by convective blood, lymphatic and interstitial transport to deep tissues. PMID:21999217

  3. Zero-tension lysimeters: An improved design to monitor colloid-facilitated contaminant transport in the vadose zone

    International Nuclear Information System (INIS)

    Thompson, M.L.; Scharf, R.L.; Shang, C.

    1995-01-01

    There is increasing evidence that mobile colloids facilitate the long-distance transport of contaminants. The mobility of fine particles and macromolecules has been linked to the movement of actinides, organic contaminants, and heavy metals through soil. Direct evidence for colloid mobility includes the presence of humic materials in deep aquifers as well as coatings of accumulated clay, organic matter, or sesquioxides on particle or aggregate surfaces in subsoil horizons of many soils. The potential for colloid-facilitated transport of contaminants from hazardous-waste sites requires adequate monitoring before, during, and after in-situ remediation treatments. Zero-tension lysimeters (ZTLs) are especially appropriate for sampling water as it moves through saturated soil, although some unsaturated flow events may be sampled as well. Because no ceramic barrier or fiberglass wick is involved to maintain tension on the water (as is the case with other lysimeters), particles suspended in the water as well as dissolved species may be sampled with ZTLs. In this report, a ZTL design is proposed that is more suitable for monitoring colloid-facilitated contaminant migration. The improved design consists of a cylinder made of polycarbonate or polytetrafluoroethylene (PTFE) that is placed below undisturbed soil material. In many soils, a hydraulically powered tube may be used to extract an undisturbed core of soil before placement of the lysimeter. In those cases, the design has significant advantages over conventional designs with respect to simplicity and speed of installation. Therefore, it will allow colloid-facilitated transport of contaminants to be monitored at more locations at a given site

  4. Structural basis of transport function in major facilitator superfamily protein from Trichoderma harzianum.

    Science.gov (United States)

    Chaudhary, Nitika; Sandhu, Padmani; Ahmed, Mushtaq; Akhter, Yusuf

    2017-02-01

    Trichothecenes are the sesquiterpenes secreted by Trichoderma spp. residing in the rhizosphere. These compounds have been reported to act as plant growth promoters and bio-control agents. The structural knowledge for the transporter proteins of their efflux remained limited. In this study, three-dimensional structure of Thmfs1 protein, a trichothecene transporter from Trichoderma harzianum, was homology modelled and further Molecular Dynamics (MD) simulations were used to decipher its mechanism. Fourteen transmembrane helices of Thmfs1 protein are observed contributing to an inward-open conformation. The transport channel and ligand binding sites in Thmfs1 are identified based on heuristic, iterative algorithm and structural alignment with homologous proteins. MD simulations were performed to reveal the differential structural behaviour occurring in the ligand free and ligand bound forms. We found that two discrete trichothecene binding sites are located on either side of the central transport tunnel running from the cytoplasmic side to the extracellular side across the Thmfs1 protein. Detailed analysis of the MD trajectories showed an alternative access mechanism between N and C-terminal domains contributing to its function. These results also demonstrate that the transport of trichodermin occurs via hopping mechanism in which the substrate molecule jumps from one binding site to another lining the transport tunnel. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Specificity of drug transport mediated by CaMDR1: a major facilitator ...

    Indian Academy of Sciences (India)

    Unknown

    CaMDR1 encodes a major facilitator superfamily (MFS) protein in Candida albicans whose expression has been linked to .... by plaque assay and the integration of CaMDR1 at the ... with recombinant virus, vAcCaMDR1 and cells infected.

  6. High-density nanopore array for selective biomolecule transport.

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Kamlesh D.

    2011-11-01

    Development of sophisticated tools capable of manipulating molecules at their own length scale enables new methods for chemical synthesis and detection. Although nanoscale devices have been developed to perform individual tasks, little work has been done on developing a truly scalable platform: a system that combines multiple components for sequential processing, as well as simultaneously processing and identifying the millions of potential species that may be present in a biological sample. The development of a scalable micro-nanofluidic device is limited in part by the ability to combine different materials (polymers, metals, semiconductors) onto a single chip, and the challenges with locally controlling the chemical, electrical, and mechanical properties within a micro or nanochannel. We have developed a unique construct known as a molecular gate: a multilayered polymer based device that combines microscale fluid channels with nanofluidic interconnects. Molecular gates have been demonstrated to selectively transport molecules between channels based on size or charge. In order to fully utilize these structures, we need to develop methods to actively control transport and identify species inside a nanopore. While previous work has been limited to creating electrical connections off-channel or metallizing the entire nanopore wall, we now have the ability to create multiple, separate conductive connections at the interior surface of a nanopore. These interior electrodes will be used for direct sensing of biological molecules, probing the electrical potential and charge distribution at the surface, and to actively turn on and off electrically driven transport of molecules through nanopores.

  7. Magnon Mode Selective Spin Transport in Compensated Ferrimagnets.

    Science.gov (United States)

    Cramer, Joel; Guo, Er-Jia; Geprägs, Stephan; Kehlberger, Andreas; Ivanov, Yurii P; Ganzhorn, Kathrin; Della Coletta, Francesco; Althammer, Matthias; Huebl, Hans; Gross, Rudolf; Kosel, Jürgen; Kläui, Mathias; Goennenwein, Sebastian T B

    2017-06-14

    We investigate the generation of magnonic thermal spin currents and their mode selective spin transport across interfaces in insulating, compensated ferrimagnet/normal metal bilayer systems. The spin Seebeck effect signal exhibits a nonmonotonic temperature dependence with two sign changes of the detected voltage signals. Using different ferrimagnetic garnets, we demonstrate the universality of the observed complex temperature dependence of the spin Seebeck effect. To understand its origin, we systematically vary the interface between the ferrimagnetic garnet and the metallic layer, and by using different metal layers we establish that interface effects play a dominating role. They do not only modify the magnitude of the spin Seebeck effect signal but in particular also alter its temperature dependence. By varying the temperature, we can select the dominating magnon mode and we analyze our results to reveal the mode selective interface transmission probabilities for different magnon modes and interfaces. The comparison of selected systems reveals semiquantitative details of the interfacial coupling depending on the materials involved, supported by the obtained field dependence of the signal.

  8. Magnon Mode Selective Spin Transport in Compensated Ferrimagnets

    KAUST Repository

    Cramer, Joel

    2017-04-13

    We investigate the generation of magnonic thermal spin currents and their mode selective spin transport across interfaces in insulating, compensated ferrimagnet/normal metal bilayer systems. The spin Seebeck effect signal exhibits a nonmonotonic temperature dependence with two sign changes of the detected voltage signals. Using different ferrimagnetic garnets, we demonstrate the universality of the observed complex temperature dependence of the spin Seebeck effect. To understand its origin, we systematically vary the interface between the ferrimagnetic garnet and the metallic layer, and by using different metal layers we establish that interface effects play a dominating role. They do not only modify the magnitude of the spin Seebeck effect signal but in particular also alter its temperature dependence. By varying the temperature, we can select the dominating magnon mode and we analyze our results to reveal the mode selective interface transmission probabilities for different magnon modes and interfaces. The comparison of selected systems reveals semiquantitative details of the interfacial coupling depending on the materials involved, supported by the obtained field dependence of the signal.

  9. Magnon Mode Selective Spin Transport in Compensated Ferrimagnets

    KAUST Repository

    Cramer, Joel; Guo, Er-Jia; Geprä gs, Stephan; Kehlberger, Andreas; Ivanov, Yurii P.; Ganzhorn, Kathrin; Della Coletta, Francesco; Althammer, Matthias; Huebl, Hans; Gross, Rudolf; Kosel, Jü rgen; Klä ui, Mathias; Goennenwein, Sebastian T. B.

    2017-01-01

    We investigate the generation of magnonic thermal spin currents and their mode selective spin transport across interfaces in insulating, compensated ferrimagnet/normal metal bilayer systems. The spin Seebeck effect signal exhibits a nonmonotonic temperature dependence with two sign changes of the detected voltage signals. Using different ferrimagnetic garnets, we demonstrate the universality of the observed complex temperature dependence of the spin Seebeck effect. To understand its origin, we systematically vary the interface between the ferrimagnetic garnet and the metallic layer, and by using different metal layers we establish that interface effects play a dominating role. They do not only modify the magnitude of the spin Seebeck effect signal but in particular also alter its temperature dependence. By varying the temperature, we can select the dominating magnon mode and we analyze our results to reveal the mode selective interface transmission probabilities for different magnon modes and interfaces. The comparison of selected systems reveals semiquantitative details of the interfacial coupling depending on the materials involved, supported by the obtained field dependence of the signal.

  10. Materials selection for a transport packaging of Mo-99

    International Nuclear Information System (INIS)

    Hara, Debora H.S.; Lucchesi, Raquel F.; Mancini, Victor A.; Rossi, Jesualdo L.; Fiore, Marina

    2015-01-01

    The radiopharmaceuticals are radioactive isotopes used in nuclear medicine for more accurate diagnosis and treatment of diseases or dysfunctions. Currently, the most important radionuclide for the preparation of radiopharmaceuticals for diagnostic purposes is technetium-99m ( 99m Tc), a product of the radioactive decay of molybdenum-99 (Mo-99). The aim of this work was the materials selection that can enable the manufacture of a package for Mo-99 transport with the aid of CES EduPack program and the methodology developed by Ashby. The ESTAR program was used to check the occurrence of Bremsstrahlung and the XCOM program was used to calculate the attenuation coefficient of gamma radiation from some of the selected materials for the shield; after, the thickness required for radiation shielding was calculated. From the results, the materials selected as potential candidates for the manufacture of the shielding were the tungsten alloys. Related to the thermal insulation and the impact protection, woods, plywoods and particle boards stand out. With regard to internal and external coatings, the selected materials focus on groups of steels and nickel alloys. (author)

  11. Separation study of Mg+2 from seawater and RO brine through a facilitated bulk liquid membrane transport using 18-Crown-6

    Directory of Open Access Journals (Sweden)

    Mir Mahdi Zahedi

    2017-12-01

    Full Text Available A facilitated bulk liquid membrane transport approach is studied for Mg(II extraction from seawater and reversed osmosis brine simulated media using 18-Crown-6 and dibenzo (DB-18-Crown-6. The work is based on investigating the experimental parameters affecting the transport efficiency, such as pH of feed and receiving phase, type of membrane solvent, temperature, type and concentration of the carrier, and stripping solution conditions. The transported amount of magnesium ions from feed phase (Mg(II = 0.059 M, NaCl = 0.01 M, pH = 3.3 across a chloroform membrane (18C6 = 0.001 M into the receiving phase (SCN− 0.1 M pH 3 was found to be %97 (±0.7 after 2.5 hr. The selectivity of the method was evaluated by performing competitive transport experiments on the mixtures containing Ca2+, Na+, K+, and Mg2+ ions.

  12. Graphene oxide-facilitated transport of levofloxacin and ciprofloxacin in saturated and unsaturated porous media.

    Science.gov (United States)

    Sun, Kaixuan; Dong, Shunan; Sun, Yuanyuan; Gao, Bin; Du, Wenchao; Xu, Hongxia; Wu, Jichun

    2018-04-15

    In this work, effects of graphene oxide (GO) on the co-transport of the two typical Fluoroquinolones (FQs) - levofloxacin (LEV) and ciprofloxacin (CIP) in saturated and unsaturated quartz sand media were studied. The adsorption isotherms showed that GO had much larger sorption capacities to LEV and CIP than sand with the largest Langmuir adsorption capacity of 409 mg g -1 (CIP-GO); while the sorption affinity of the two FQs onto the two adsorbents might follow the order of CIP-sand > LEV-sand > LEV-GO > CIP-GO. GO promoted the mobility of the two FQs in both saturated and unsaturated porous media due to its strong mobility and sorption capacity. The GO-bound LEV/CIP was responsible for the LEV/CIP transport in the porous media, and transport of GO-bound FQs increased with the increasing of initial GO concentration. Under unsaturated conditions, moisture showed little effect on the transport of GO-bound CIP; however, the mobility of GO-bound LEV reduced with the decreasing of moisture content, suggesting the transport of adsorbed LEV from GO to air-water interface. GO sorption reduced the antibacterial ability of the two FQs, but they were still effective in inhibiting E. coli growth. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Habitat selection, facilitation, and biotic settlement cues affect distribution and performance of coral recruits in French Polynesia.

    Science.gov (United States)

    Price, Nichole

    2010-07-01

    Habitat selection can determine the distribution and performance of individuals if the precision with which sites are chosen corresponds with exposure to risks or resources. Contrastingly, facilitation can allow persistence of individuals arriving by chance and potentially maladapted to local abiotic conditions. For marine organisms, selection of a permanent attachment site at the end of their larval stage or the presence of a facilitator can be a critical determinant of recruitment success. In coral reef ecosystems, it is well known that settling planula larvae of reef-building corals use coarse environmental cues (i.e., light) for habitat selection. Although laboratory studies suggest that larvae can also use precise biotic cues produced by crustose coralline algae (CCA) to select attachment sites, the ecological consequences of biotic cues for corals are poorly understood in situ. In a field experiment exploring the relative importance of biotic cues and variability in habitat quality to recruitment of hard corals, pocilloporid and acroporid corals recruited more frequently to one species of CCA, Titanoderma prototypum, and significantly less so to other species of CCA; these results are consistent with laboratory assays from other studies. The provision of the biotic cue accurately predicted coral recruitment rates across habitats of varying quality. At the scale of CCA, corals attached to the "preferred" CCA experienced increased survivorship while recruits attached elsewhere had lower colony growth and survivorship. For reef-building corals, the behavioral selection of habitat using chemical cues both reduces the risk of incidental mortality and indicates the presence of a facilitator.

  14. Transporter-Guided Delivery of Nanoparticles to Improve Drug Permeation across Cellular Barriers and Drug Exposure to Selective Cell Types

    Directory of Open Access Journals (Sweden)

    Longfa Kou

    2018-01-01

    Full Text Available Targeted nano-drug delivery systems conjugated with specific ligands to target selective cell-surface receptors or transporters could enhance the efficacy of drug delivery and therapy. Transporters are expressed differentially on the cell-surface of different cell types, and also specific transporters are expressed at higher than normal levels in selective cell types under pathological conditions. They also play a key role in intestinal absorption, delivery via non-oral routes (e.g., pulmonary route and nasal route, and transfer across biological barriers (e.g., blood–brain barrier and blood–retinal barrier. As such, the cell-surface transporters represent ideal targets for nano-drug delivery systems to facilitate drug delivery to selective cell types under normal or pathological conditions and also to avoid off-target adverse side effects of the drugs. There is increasing evidence in recent years supporting the utility of cell-surface transporters in the field of nano-drug delivery to increase oral bioavailability, to improve transfer across the blood–brain barrier, and to enhance delivery of therapeutics in a cell-type selective manner in disease states. Here we provide a comprehensive review of recent advancements in this interesting and important area. We also highlight certain key aspects that need to be taken into account for optimal development of transporter-assisted nano-drug delivery systems.

  15. Facilitation of Drug Transport across the Blood–Brain Barrier with Ultrasound and Microbubbles

    OpenAIRE

    Meairs, Stephen

    2015-01-01

    Medical treatment options for central nervous system (CNS) diseases are limited due to the inability of most therapeutic agents to penetrate the blood–brain barrier (BBB). Although a variety of approaches have been investigated to open the BBB for facilitation of drug delivery, none has achieved clinical applicability. Mounting evidence suggests that ultrasound in combination with microbubbles might be useful for delivery of drugs to the brain through transient opening of the BBB. This techni...

  16. Human copper transporter 2 is localized in late endosomes and lysosomes and facilitates cellular copper uptake

    NARCIS (Netherlands)

    Berghe, van den P.V.E; Folmer, D.E.; Malingré, H.E.M.; Beurden, van E.; Klomp, A.E.M.; Sluis, van de B.; Merkx, M.; Berger, R.J.; Klomp, L.W.J.

    2007-01-01

    High-affinity cellular copper uptake is mediated by the CTR (copper transporter) 1 family of proteins. The highly homologous hCTR (human CTR) 2 protein has been identified, but its function in copper uptake is currently unknown. To characterize the role of hCTR2 in copper homoeostasis,

  17. Cellular fatty acid transport in heart and skeletal muscle as facilitated by proteins

    NARCIS (Netherlands)

    Luiken, J. J.; Schaap, F. G.; van Nieuwenhoven, F. A.; van der Vusse, G. J.; Bonen, A.; Glatz, J. F.

    1999-01-01

    Despite the importance of long-chain fatty acids (FA) as fuels for heart and skeletal muscles, the mechanism of their cellular uptake has not yet been clarified. There is dispute as to whether FA are taken up by the muscle cells via passive diffusion and/or carrier-mediated transport. Kinetic

  18. An Active Learning Exercise to Facilitate Understanding of Nephron Function: Anatomy and Physiology of Renal Transporters

    Science.gov (United States)

    Dirks-Naylor, Amie J.

    2016-01-01

    Renal transport is a central mechanism underlying electrolyte homeostasis, acid base balance and other essential functions of the kidneys in human physiology. Thus, knowledge of the anatomy and physiology of the nephron is essential for the understanding of kidney function in health and disease. However, students find this content difficult to…

  19. Mucolipin 1 positively regulates TLR7 responses in dendritic cells by facilitating RNA transportation to lysosomes.

    Science.gov (United States)

    Li, Xiaobing; Saitoh, Shin-Ichiroh; Shibata, Takuma; Tanimura, Natsuko; Fukui, Ryutaro; Miyake, Kensuke

    2015-02-01

    Toll-like receptor 7 (TLR7) and TLR9 sense microbial single-stranded RNA (ssRNA) and ssDNA in endolysosomes. Nucleic acid (NA)-sensing in endolysosomes is thought to be important for avoiding TLR7/9 responses to self-derived NAs. Aberrant self-derived NA transportation to endolysosomes predisposes to autoimmune diseases. To restrict NA-sensing in endolysosomes, TLR7/9 trafficking is tightly controlled by a multiple transmembrane protein Unc93B1. In contrast to TLR7/9 trafficking, little is known about a mechanism underlying NA transportation. We here show that Mucolipin 1 (Mcoln1), a member of the transient receptor potential (TRP) cation channel gene family, has an important role in ssRNA trafficking into lysosomes. Mcoln1(-/-) dendritic cells (DCs) showed impaired TLR7 responses to ssRNA. A mucolipin agonist specifically enhanced TLR7 responses to ssRNAs. The channel activity of Mcoln1 is activated by a phospholipid phosphatidylinositol (3,5) bisphosphate (PtdIns(3,5)P2), which is generated by a class III lipid kinase PIKfyve. A PIKfyve inhibitor completely inhibited TLR7 responses to ssRNA in DCs. Confocal analyses showed that ssRNA transportation to lysosomes in DCs was impaired by PIKfyve inhibitor as well as by the lack of Mcoln1. Transportation of TLR9 ligands was also impaired by the PIKfyve inhibitor. These results demonstrate that the PtdIns(3,5)P2-Mcoln1 axis has an important role in ssRNA transportation into lysosomes in DCs. © The Japanese Society for Immunology. 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Colloid-facilitated radionuclide transport in the fractured rock: effects of decay chain and limited matrix diffusion

    International Nuclear Information System (INIS)

    Park, J. B.; Park, J. W.; Lee, E. Y.; Kim, C. R.

    2002-01-01

    Colloid-facilitated radionuclide transport in the fractured rock is studies by considering radioactive decay chain and limited matrix diffusion into surrounding porous media. Semi-analytical solution in the Laplace domain is obtained from the mass balance equation of radionuclides and colloid particles. Numerical inversion of the Laplace solution is used to get the concentration profiles both in a fracture and in rock matrix. There issues are analyzed for the radionuclide concentration in a fracture by 1) formation constant of pseudo-colloid, 2) filtration coefficient of radio-colloid and 3) effective diffusion depth into the surrounding porous rock media

  1. A Theoretical Basis for Adult Learning Facilitation: Review of Selected Articles

    Science.gov (United States)

    Muneja, Mussa S.

    2015-01-01

    The aim of this paper is to synthesize a theoretical basis for adult learning facilitation in order to provide a valuable systematic resource in the field of adult education. The paper has reviewed 6 journal articles with topics ranging from theory of andragogy; the effect of globalization on adult learning; the contribution of Malcolm Knowles;…

  2. Facilitated transport of glucose from blood to brain in man and the effect of moderate hypoglycaemia on cerebral glucose utilization

    International Nuclear Information System (INIS)

    Blomqvist, G.; Widen, L.; Hellstrand, E.; Gutniak, M.; Grill, V.

    1991-01-01

    The effect of steady-state moderate hypoglycaemia on human brain homeostasis has been studied with positron emission tomography using D-glucose 11 C(ul) as tracer. To rule out any effects of insulin, the plasma insulin concentration was maintained at the same level under normo- and hypoglycaemic conditions. Reduction of blood glucose by 55% increased the glucose clearance through the blood-brain barrier by 50% and reduced brain glucose consumption by 40%. Blood flow was not affected. The results are consistent with facilitated transport of glucose from blood to brain in humans. The maximal transport rate of glucose from blood to brain was found to be 62±19 (mean±SEM) μmol hg -1 min -1 , and the half-saturation constant was found to be 4.1±3.2 mM. (orig.)

  3. Isolation and functional analysis of Thmfs1, the first major facilitator superfamily transporter from the biocontrol fungus Trichoderma harzianum.

    Science.gov (United States)

    Liu, Mu; Liu, Jun; Wang, Wei Min

    2012-10-01

    A novel major facilitator superfamily (MFS) transporter gene, Thmfs1, was isolated from Trichoderma harzianum (T. harzianum). A Thmfs1 over-expressing mutant displayed enhanced antifungal activity and fungicide tolerance, while the Thmfs1 disruption mutant showed the opposite trend. Trichodermin production in Thmfs1 disruption group (185 mg l(-1)) was decreased by less than 17 % compared to the parental strain, suggesting that Thmfs1 is not mainly responsible for trichodermin secretion. Real-time PCR showed that Thmfs1 transcript level could be induced by a certain range of trichodermin concentrations, while expression of Tri5, encoding a trichodiene synthase, was strongly inhibited under these conditions. To our knowledge, Thmfs1 is the first MFS transporter gene identified in T. harzianum.

  4. Two Major Facilitator Superfamily Sugar Transporters from Trichoderma reesei and Their Roles in Induction of Cellulase Biosynthesis*

    Science.gov (United States)

    Zhang, Weixin; Kou, Yanbo; Xu, Jintao; Cao, Yanli; Zhao, Guolei; Shao, Jing; Wang, Hai; Wang, Zhixing; Bao, Xiaoming; Chen, Guanjun; Liu, Weifeng

    2013-01-01

    Proper perception of the extracellular insoluble cellulose is key to initiating the rapid synthesis of cellulases by cellulolytic Trichoderma reesei. Uptake of soluble oligosaccharides derived from cellulose hydrolysis represents a potential point of control in the induced cascade. In this study, we identified a major facilitator superfamily sugar transporter Stp1 capable of transporting cellobiose by reconstructing a cellobiose assimilation system in Saccharomyces cerevisiae. The absence of Stp1 in T. reesei resulted in differential cellulolytic response to Avicel versus cellobiose. Transcriptional profiling revealed a different expression profile in the Δstp1 strain from that of wild-type strain in response to Avicel and demonstrated that Stp1 somehow repressed induction of the bulk of major cellulase and hemicellulose genes. Two other putative major facilitator superfamily sugar transporters were, however, up-regulated in the profiling. Deletion of one of them identified Crt1 that was required for growth and enzymatic activity on cellulose or lactose, but was not required for growth or hemicellulase activity on xylan. The essential role of Crt1 in cellulase induction did not seem to rely on its transporting activity because the overall uptake of cellobiose or sophorose by T. reesei was not compromised in the absence of Crt1. Phylogenetic analysis revealed that orthologs of Crt1 exist in the genomes of many filamentous ascomycete fungi capable of degrading cellulose. These data thus shed new light on the mechanism by which T. reesei senses and transmits the cellulose signal and offers potential strategies for strain improvement. PMID:24085297

  5. Emission of volatile organic compounds from petunia flowers is facilitated by an ABC transporter.

    Science.gov (United States)

    Adebesin, Funmilayo; Widhalm, Joshua R; Boachon, Benoît; Lefèvre, François; Pierman, Baptiste; Lynch, Joseph H; Alam, Iftekhar; Junqueira, Bruna; Benke, Ryan; Ray, Shaunak; Porter, Justin A; Yanagisawa, Makoto; Wetzstein, Hazel Y; Morgan, John A; Boutry, Marc; Schuurink, Robert C; Dudareva, Natalia

    2017-06-30

    Plants synthesize a diversity of volatile molecules that are important for reproduction and defense, serve as practical products for humans, and influence atmospheric chemistry and climate. Despite progress in deciphering plant volatile biosynthesis, their release from the cell has been poorly understood. The default assumption has been that volatiles passively diffuse out of cells. By characterization of a Petunia hybrida adenosine triphosphate-binding cassette (ABC) transporter, PhABCG1, we demonstrate that passage of volatiles across the plasma membrane relies on active transport. PhABCG1 down-regulation by RNA interference results in decreased emission of volatiles, which accumulate to toxic levels in the plasma membrane. This study provides direct proof of a biologically mediated mechanism of volatile emission. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  6. Three tapasin docking sites in TAP cooperate to facilitate transporter stabilization and heterodimerization

    Science.gov (United States)

    Leonhardt, Ralf M.; Abrahimi, Parwiz; Mitchell, Susan M.; Cresswell, Peter

    2014-01-01

    The transporter associated with antigen processing (TAP) translocates peptide antigens into the lumen of the endoplasmic reticulum (ER) for loading onto major histocompatibility complex (MHC) class I molecules. MHC class I acquires its peptide cargo in the peptide loading complex (PLC), an oligomeric complex that the chaperone tapasin organizes by bridging TAP to MHC class I and recruiting accessory molecules such as ERp57 and calreticulin. Three tapasin binding sites on TAP have been described, two of which are located in the N-terminal domains (N domains) of TAP1 and TAP2. The third binding site is present in the core transmembrane domain (coreTMD) of TAP1 and is only used by the unassembled subunits. Tapasin is required to promote TAP stability, but through which binding site(s) it is acting is unknown. In particular the role of tapasin binding to the coreTMD of TAP1 single chains is mysterious as this interaction is lost upon TAP2 association. In this study, we map the respective binding site in TAP1 to the polar face of the amphipathic transmembrane helix TM9 and identify key residues that are essential to establish the interaction. We find that this interaction is dispensable for the peptide transport function but essential to achieve full stability of human TAP1. The interaction is also required for proper heterodimerization of the transporter. Based on similar results obtained using TAP mutants lacking tapasin binding to either N domain, we conclude that all three tapasin-binding sites in TAP cooperate to achieve high transporter stability and efficient heterodimerization. PMID:24501197

  7. Facilitated transport of Hg(II) through novel activated composite membranes

    Energy Technology Data Exchange (ETDEWEB)

    Paez-Hernandez, M.E. [Universidad Autonoma Metropolitana-Azcapotzalco, Departamento de Materiales, Area de Ciencia de los Materiales, Col. Reynosa-Tamaulipas (Mexico); Universidad Autonoma del Estado de Hidalgo, Centro de Investigaciones Quimicas, Pachuca, Hidalgo (Mexico); Aguilar-Arteaga, K. [Universidad Autonoma del Estado de Hidalgo, Centro de Investigaciones Quimicas, Pachuca, Hidalgo (Mexico); Valiente, M. [Universitat Autonoma de Barcelona, Departament de Quimica, Unitat Analitica, Centre GTS, Facultat de Ciencies, Bellaterra, Barcelona (Spain); Ramirez-Silva, M.T. [Universidad Autonoma Metropolitana-Iztapalapa, Departamento de Quimica, Area de Quimica Analitica, Laboratorio R-105, Col. Vicentina, Mexico D.F. (Mexico); Romero-Romo, M.; Palomar-Pardave, M. [Universidad Autonoma Metropolitana-Azcapotzalco, Departamento de Materiales, Area de Ciencia de los Materiales, Col. Reynosa-Tamaulipas (Mexico)

    2004-10-01

    The results presented in this work deal with the prime application of activated composite membranes (ACMs) for the transport of Hg(II) ions in a continuous extraction-re-extraction system using di-(2-ethylhexyl)dithiophosphoric acid (DTPA) as carrier. The effects of variables such as the pH, the nature of the acid and the concentration of the casting solutions on the transport of Hg(II) are also investigated. When the ACM was prepared with a 0.5 M DTPA solution and when the feed solution contained 2.5 x 10{sup -4} M Hg(II) in 0.1 M HCl, the amount of mercury extracted was greater than 76%. The re-extracted mercury was subsequently recovered by means of a stripping phase comprising 0.3 M thiourea solution in 2 M H{sub 2}SO{sub 4}, yielding 54% of the initial amount of mercury after transport had taken place for 180 min. (orig.)

  8. Oxytocin selectively facilitates learning with social feedback and increases activity and functional connectivity in emotional memory and reward processing regions.

    Science.gov (United States)

    Hu, Jiehui; Qi, Song; Becker, Benjamin; Luo, Lizhu; Gao, Shan; Gong, Qiyong; Hurlemann, René; Kendrick, Keith M

    2015-06-01

    In male Caucasian subjects, learning is facilitated by receipt of social compared with non-social feedback, and the neuropeptide oxytocin (OXT) facilitates this effect. In this study, we have first shown a cultural difference in that male Chinese subjects actually perform significantly worse in the same reinforcement associated learning task with social (emotional faces) compared with non-social feedback. Nevertheless, in two independent double-blind placebo (PLC) controlled between-subject design experiments we found OXT still selectively facilitated learning with social feedback. Similar to Caucasian subjects this OXT effect was strongest with feedback using female rather than male faces. One experiment performed in conjunction with functional magnetic resonance imaging showed that during the response, but not feedback phase of the task, OXT selectively increased activity in the amygdala, hippocampus, parahippocampal gyrus and putamen during the social feedback condition, and functional connectivity between the amygdala and insula and caudate. Therefore, OXT may be increasing the salience and reward value of anticipated social feedback. In the PLC group, response times and state anxiety scores during social feedback were associated with signal changes in these same regions but not in the OXT group. OXT may therefore have also facilitated learning by reducing anxiety in the social feedback condition. Overall our results provide the first evidence for cultural differences in social facilitation of learning per se, but a similar selective enhancement of learning with social feedback under OXT. This effect of OXT may be associated with enhanced responses and functional connectivity in emotional memory and reward processing regions. © 2015 Wiley Periodicals, Inc.

  9. Two endoplasmic reticulum (ER) membrane proteins that facilitate ER-to-Golgi transport of glycosylphosphatidylinositol-anchored proteins.

    Science.gov (United States)

    Barz, W P; Walter, P

    1999-04-01

    Many eukaryotic cell surface proteins are anchored in the lipid bilayer through glycosylphosphatidylinositol (GPI). GPI anchors are covalently attached in the endoplasmic reticulum (ER). The modified proteins are then transported through the secretory pathway to the cell surface. We have identified two genes in Saccharomyces cerevisiae, LAG1 and a novel gene termed DGT1 (for "delayed GPI-anchored protein transport"), encoding structurally related proteins with multiple membrane-spanning domains. Both proteins are localized to the ER, as demonstrated by immunofluorescence microscopy. Deletion of either gene caused no detectable phenotype, whereas lag1Delta dgt1Delta cells displayed growth defects and a significant delay in ER-to-Golgi transport of GPI-anchored proteins, suggesting that LAG1 and DGT1 encode functionally redundant or overlapping proteins. The rate of GPI anchor attachment was not affected, nor was the transport rate of several non-GPI-anchored proteins. Consistent with a role of Lag1p and Dgt1p in GPI-anchored protein transport, lag1Delta dgt1Delta cells deposit abnormal, multilayered cell walls. Both proteins have significant sequence similarity to TRAM, a mammalian membrane protein thought to be involved in protein translocation across the ER membrane. In vivo translocation studies, however, did not detect any defects in protein translocation in lag1Delta dgt1Delta cells, suggesting that neither yeast gene plays a role in this process. Instead, we propose that Lag1p and Dgt1p facilitate efficient ER-to-Golgi transport of GPI-anchored proteins.

  10. Effects of oil dispersants on settling of marine sediment particles and particle-facilitated distribution and transport of oil components.

    Science.gov (United States)

    Cai, Zhengqing; Fu, Jie; Liu, Wen; Fu, Kunming; O'Reilly, S E; Zhao, Dongye

    2017-01-15

    This work investigated effects of three model oil dispersants (Corexit EC9527A, Corexit EC9500A and SPC1000) on settling of fine sediment particles and particle-facilitated distribution and transport of oil components in sediment-seawater systems. All three dispersants enhanced settling of sediment particles. The nonionic surfactants (Tween 80 and Tween 85) play key roles in promoting particle aggregation. Yet, the effects varied with environmental factors (pH, salinity, DOM, and temperature). Strongest dispersant effect was observed at neutral or alkaline pH and in salinity range of 0-3.5wt%. The presence of water accommodated oil and dispersed oil accelerated settling of the particles. Total petroleum hydrocarbons in the sediment phase were increased from 6.9% to 90.1% in the presence of Corexit EC9527A, and from 11.4% to 86.7% for PAHs. The information is useful for understanding roles of oil dispersants in formation of oil-sediment aggregates and in sediment-facilitated transport of oil and PAHs in marine eco-systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Golgi localized barley MTP8 proteins facilitate Mn transport

    DEFF Research Database (Denmark)

    Pedas, Pai Rosager; Schiller, Michaela; Hegelund, Josefine Nymark

    2014-01-01

    Many metabolic processes in plants are regulated by manganese (Mn) but limited information is available on the molecular mechanisms controlling cellular Mn homeostasis. In this study, a yeast assay was used to isolate and characterize two genes, MTP8.1 and MTP8.2 , which encode membrane...... in yeast, MTP8.1 and MTP8.2 were found to be Mn transporters catalysing Mn efflux in a similar manner as the Golgi localized endogenous yeast protein Pmr1p. The level of MTP8.1 transcripts in barley roots increased with external Mn supply ranging from deficiency to toxicity, while MTP8.2 transcripts...

  12. Uranium facilitated transport by water-dispersible colloids in field and soil columns

    International Nuclear Information System (INIS)

    Crancon, P.; Pili, E.; Charlet, L.

    2010-01-01

    The transport of uranium through a sandy podzolic soil has been investigated in the field and in column experiments. Field monitoring, numerous years after surface contamination by depleted uranium deposits, revealed a 20 cm deep uranium migration in soil. Uranium retention in soil is controlled by the 238 U initially present in the soil column and 233 U brought by input solution are desorbed. The mobilization process observed experimentally after a drop of ionic strength may account for a rapid uranium migration in the field after a rainfall event, and for the significant uranium concentrations found in deep soil horizons and in groundwater, 1 km downstream from the pollution source.

  13. Evaluating gaze-based interface tools to facilitate point-and-select tasks with small targets

    DEFF Research Database (Denmark)

    Skovsgaard, Henrik; Mateo, Julio C.; Hansen, John Paulin

    2011-01-01

    -and-select tasks. We conducted two experiments comparing the performance of dwell, magnification and zoom methods in point-and-select tasks with small targets in single- and multiple-target layouts. Both magnification and zoom showed higher hit rates than dwell. Hit rates were higher when using magnification than...

  14. An Assessment Protocol for Selective Mutism: Analogue Assessment Using Parents as Facilitators.

    Science.gov (United States)

    Schill, Melissa T.; And Others

    1996-01-01

    Assesses protocol for conducting a functional analysis of maintaining variables for children with selective mutism. A parent was trained in and later applied various behavior strategies designed to increase speech in an eight-year-old girl with selective mutism. Parent and child ratings of treatment were positive. Presents implications for future…

  15. Concurrent Working Memory Load Can Facilitate Selective Attention: Evidence for Specialized Load

    Science.gov (United States)

    Park, Soojin; Kim, Min-Shik; Chun, Marvin M.

    2007-01-01

    Load theory predicts that concurrent working memory load impairs selective attention and increases distractor interference (N. Lavie, A. Hirst, J. W. de Fockert, & E. Viding, see record 2004-17825-003). Here, the authors present new evidence that the type of concurrent working memory load determines whether load impairs selective attention or not.…

  16. Selected legal and regulatory concerns affecting domestic energy transportation systems

    International Nuclear Information System (INIS)

    Schuller, C.R.

    1979-07-01

    This report provides assessments of eight legal and regulatory concerns that may affect energy material transportation in the US during the rest of the century: state authority to regulate nuclear materials transport, divestiture of petroleum pipelines from major integrated oil companies, problems affecting the natural gas transportation system, capabilities of energy transportation systems during emergencies, Federal coal pipeline legislation, ability of Federal agencies to anticipate railroad difficulties, abandonment of uneconomic railroad lines, and impact of the Panama Canal treaty upon US energy transportation

  17. The role of organic complexants and microparticulates in the facilitated transport of radionuclides

    International Nuclear Information System (INIS)

    Schilk, A.J.; Robertson, D.E.; Abel, K.H.; Thomas, C.W.

    1996-12-01

    This progress report describes the results of ongoing radiological and geochemical investigations of the mechanisms of radionuclide transport in groundwater at two low-level waste (LLW) disposal sites within the waste management area of the Chalk River Laboratories (CRL), Ontario, Canada. These sites, the Chemical Pit liquid disposal facility and the Waste Management Area C solid LLW disposal site, have provided valuable 30- to 40-year-old field locations for characterizing the migration of radionuclides and evaluating a number of recent site performance objectives for LLW disposal facilities. This information will aid the NRC and other federal, state, and local regulators, as well as LLW disposal site developers and waste generators, in maximizing the effectiveness of existing or projected LLW disposal facilities for isolating radionuclides from the general public and thereby improving the health and safety aspects of LLW disposal

  18. Uranium facilitated transport by water-dispersible colloids in field and soil columns

    Energy Technology Data Exchange (ETDEWEB)

    Crancon, P.; Pili, E. [CEA Bruyeres-le-Chatel, DIF, 91 (France); Charlet, L. [Univ Grenoble 1, Lab Geophys Interne and Tectonophys LGIT OSUG, CNRS, UJF, UMR5559, F-38041 Grenoble 9 (France)

    2010-07-01

    The transport of uranium through a sandy podsolic soil has been investigated in the field and in column experiments. Field monitoring, numerous years after surface contamination by depleted uranium deposits, revealed a 20 cm deep uranium migration in soil. Uranium retention in soil is controlled by the {<=} 50 {mu}m mixed humic and clayey coatings in the first 40 cm i.e. in the E horizon. Column experiments of uranium transport under various conditions were run using isotopic spiking. After 100 pore volumes elution, 60% of the total input uranium is retained in the first 2 cm of the column. Retardation factor of uranium on E horizon material ranges from 1300 (column) to 3000 (batch). In parallel to this slow uranium migration, we experimentally observed a fast elution related to humic colloids of about 1-5% of the total-uranium input, transferred at the mean pore-water velocity through the soil column. In order to understand the effect of rain events, ionic strength of the input solution was sharply changed. Humic colloids are retarded when ionic strength increases, while a major mobilization of humic colloids and colloid-borne uranium occurs as ionic strength decreases. Isotopic spiking shows that both {sup 238}U initially present in the soil column and {sup 233}U brought by input solution are desorbed. The mobilization process observed experimentally after a drop of ionic strength may account for a rapid uranium migration in the field after a rainfall event, and for the significant uranium concentrations found in deep soil horizons and in groundwater, 1 km downstream from the pollution source. (authors)

  19. Uranium facilitated transport by water-dispersible colloids in field and soil columns

    Energy Technology Data Exchange (ETDEWEB)

    Crancon, P., E-mail: pierre.crancon@cea.fr [CEA, DAM, DIF, F-91297 Arpajon (France); Pili, E. [CEA, DAM, DIF, F-91297 Arpajon (France); Charlet, L. [Laboratoire de Geophysique Interne et Tectonophysique (LGIT-OSUG), University of Grenoble-I, UMR5559-CNRS-UJF, BP53, 38041 Grenoble cedex 9 (France)

    2010-04-01

    The transport of uranium through a sandy podzolic soil has been investigated in the field and in column experiments. Field monitoring, numerous years after surface contamination by depleted uranium deposits, revealed a 20 cm deep uranium migration in soil. Uranium retention in soil is controlled by the < 50 {mu}m mixed humic and clayey coatings in the first 40 cm i.e. in the E horizon. Column experiments of uranium transport under various conditions were run using isotopic spiking. After 100 pore volumes elution, 60% of the total input uranium is retained in the first 2 cm of the column. Retardation factor of uranium on E horizon material ranges from 1300 (column) to 3000 (batch). In parallel to this slow uranium migration, we experimentally observed a fast elution related to humic colloids of about 1-5% of the total-uranium input, transferred at the mean porewater velocity through the soil column. In order to understand the effect of rain events, ionic strength of the input solution was sharply changed. Humic colloids are retarded when ionic strength increases, while a major mobilization of humic colloids and colloid-borne uranium occurs as ionic strength decreases. Isotopic spiking shows that both {sup 238}U initially present in the soil column and {sup 233}U brought by input solution are desorbed. The mobilization process observed experimentally after a drop of ionic strength may account for a rapid uranium migration in the field after a rainfall event, and for the significant uranium concentrations found in deep soil horizons and in groundwater, 1 km downstream from the pollution source.

  20. Facilitation of Drug Transport across the Blood–Brain Barrier with Ultrasound and Microbubbles

    Directory of Open Access Journals (Sweden)

    Stephen Meairs

    2015-08-01

    Full Text Available Medical treatment options for central nervous system (CNS diseases are limited due to the inability of most therapeutic agents to penetrate the blood–brain barrier (BBB. Although a variety of approaches have been investigated to open the BBB for facilitation of drug delivery, none has achieved clinical applicability. Mounting evidence suggests that ultrasound in combination with microbubbles might be useful for delivery of drugs to the brain through transient opening of the BBB. This technique offers a unique non-invasive avenue to deliver a wide range of drugs to the brain and promises to provide treatments for CNS disorders with the advantage of being able to target specific brain regions without unnecessary drug exposure. If this method could be applied for a range of different drugs, new CNS therapeutic strategies could emerge at an accelerated pace that is not currently possible in the field of drug discovery and development. This article reviews both the merits and potential risks of this new approach. It assesses methods used to verify disruption of the BBB with MRI and examines the results of studies aimed at elucidating the mechanisms of opening the BBB with ultrasound and microbubbles. Possible interactions of this novel delivery method with brain disease, as well as safety aspects of BBB disruption with ultrasound and microbubbles are addressed. Initial translational research for treatment of brain tumors and Alzheimer’s disease is presented.

  1. Facilitation of Drug Transport across the Blood-Brain Barrier with Ultrasound and Microbubbles.

    Science.gov (United States)

    Meairs, Stephen

    2015-08-31

    Medical treatment options for central nervous system (CNS) diseases are limited due to the inability of most therapeutic agents to penetrate the blood-brain barrier (BBB). Although a variety of approaches have been investigated to open the BBB for facilitation of drug delivery, none has achieved clinical applicability. Mounting evidence suggests that ultrasound in combination with microbubbles might be useful for delivery of drugs to the brain through transient opening of the BBB. This technique offers a unique non-invasive avenue to deliver a wide range of drugs to the brain and promises to provide treatments for CNS disorders with the advantage of being able to target specific brain regions without unnecessary drug exposure. If this method could be applied for a range of different drugs, new CNS therapeutic strategies could emerge at an accelerated pace that is not currently possible in the field of drug discovery and development. This article reviews both the merits and potential risks of this new approach. It assesses methods used to verify disruption of the BBB with MRI and examines the results of studies aimed at elucidating the mechanisms of opening the BBB with ultrasound and microbubbles. Possible interactions of this novel delivery method with brain disease, as well as safety aspects of BBB disruption with ultrasound and microbubbles are addressed. Initial translational research for treatment of brain tumors and Alzheimer's disease is presented.

  2. The major facilitator superfamily transporter Knq1p modulates boron homeostasis in Kluyveromyces lactis.

    Science.gov (United States)

    Svrbicka, Alexandra; Toth Hervay, Nora; Gbelska, Yvetta

    2016-03-01

    Boron is an essential micronutrient for living cells, yet its excess causes toxicity. To date, the mechanisms of boron toxicity are poorly understood. Recently, the ScATR1 gene has been identified encoding the main boron efflux pump in Saccharomyces cerevisiae. In this study, we analyzed the ScATR1 ortholog in Kluyveromyces lactis--the KNQ1 gene, to understand whether it participates in boron stress tolerance. We found that the KNQ1 gene, encoding a permease belonging to the major facilitator superfamily, is required for K. lactis boron tolerance. Deletion of the KNQ1 gene led to boron sensitivity and its overexpression increased K. lactis boron tolerance. The KNQ1 expression was induced by boron and the intracellular boron concentration was controlled by Knq1p. The KNQ1 promoter contains two putative binding motifs for the AP-1-like transcription factor KlYap1p playing a central role in oxidative stress defense. Our results indicate that the induction of the KNQ1 expression requires the presence of KlYap1p and that Knq1p like its ortholog ScAtr1p in S. cerevisiae functions as a boron efflux pump providing boron resistance in K. lactis.

  3. Ultrasound-facilitated transport of silver chloride (AgCl) particles in fish skin.

    Science.gov (United States)

    Frenkel, V; Kimmel, E; Iger, Y

    2000-08-10

    Electron-dense nano-particles in aqueous suspension were administered by immersion into the epidermis of fish using ultrasound in the therapeutic range. Enhanced permeability of the tissues to the particles was achieved by acoustic cavitation, which induced a controlled level of necrosis in the outer cell layers, and by non-cavitational exposures, which widened intercellular spaces of non-necrosed tissue in deeper regions of the epidermis. Both particle concentration and penetration depth were quantified using transmission electron microscopy. While cavitation-induced perforation was necessary for particles to penetrate into the tissues, non-cavitational exposures during immersions increased the particle flux towards the skin surface, as well as the diffusion rate of the particles within the epidermis and their depth of penetration. The technique described above may potentially be applied for non-stressful, mass-administration of substances into aquatic animals, as well as the relatively new field of ultrasound-facilitated delivery in moist epithelial tissues in humans.

  4. Facilitated charge transport in ternary interconnected electrodes for flexible supercapacitors with excellent power characteristics

    Science.gov (United States)

    Chen, Wanjun; He, Yongmin; Li, Xiaodong; Zhou, Jinyuan; Zhang, Zhenxing; Zhao, Changhui; Gong, Chengshi; Li, Shuankui; Pan, Xiaojun; Xie, Erqing

    2013-11-01

    Flexible and high performance supercapacitors are very critical in modern society. In order to develop the flexible supercapacitors with high power density, free-standing and flexible three-dimensional graphene/carbon nanotubes/MnO2 (3DG/CNTs/MnO2) composite electrodes with interconnected ternary 3D structures were fabricated, and the fast electron and ion transport channels were effectively constructed in the rationally designed electrodes. Consequently, the obtained 3DG/CNTs/MnO2 composite electrodes exhibit superior specific capacitance and rate capability compared to 3DG/MnO2 electrodes. Furthermore, the 3DG/CNTs/MnO2 based asymmetric supercapacitor demonstrates the maximum energy and power densities of 33.71 W h kg-1 and up to 22 727.3 W kg-1, respectively. Moreover, the asymmetric supercapacitor exhibits excellent cycling stability with 95.3% of the specific capacitance maintained after 1000 cycle tests. Our proposed synthesis strategy to construct the novel ternary 3D structured electrodes can be efficiently applied to other high performance energy storage/conversion systems.Flexible and high performance supercapacitors are very critical in modern society. In order to develop the flexible supercapacitors with high power density, free-standing and flexible three-dimensional graphene/carbon nanotubes/MnO2 (3DG/CNTs/MnO2) composite electrodes with interconnected ternary 3D structures were fabricated, and the fast electron and ion transport channels were effectively constructed in the rationally designed electrodes. Consequently, the obtained 3DG/CNTs/MnO2 composite electrodes exhibit superior specific capacitance and rate capability compared to 3DG/MnO2 electrodes. Furthermore, the 3DG/CNTs/MnO2 based asymmetric supercapacitor demonstrates the maximum energy and power densities of 33.71 W h kg-1 and up to 22 727.3 W kg-1, respectively. Moreover, the asymmetric supercapacitor exhibits excellent cycling stability with 95.3% of the specific capacitance maintained

  5. Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Executive summary

    International Nuclear Information System (INIS)

    Simmons, C.S.; Cole, C.R.

    1985-05-01

    This document was written to provide guidance to managers and site operators on how ground-water transport codes should be selected for assessing burial site performance. There is a need for a formal approach to selecting appropriate codes from the multitude of potentially useful ground-water transport codes that are currently available. Code selection is a problem that requires more than merely considering mathematical equation-solving methods. These guidelines are very general and flexible and are also meant for developing systems simulation models to be used to assess the environmental safety of low-level waste burial facilities. Code selection is only a single aspect of the overall objective of developing a systems simulation model for a burial site. The guidance given here is mainly directed toward applications-oriented users, but managers and site operators need to be familiar with this information to direct the development of scientifically credible and defensible transport assessment models. Some specific advice for managers and site operators on how to direct a modeling exercise is based on the following five steps: identify specific questions and study objectives; establish costs and schedules for achieving answers; enlist the aid of professional model applications group; decide on approach with applications group and guide code selection; and facilitate the availability of site-specific data. These five steps for managers/site operators are discussed in detail following an explanation of the nine systems model development steps, which are presented first to clarify what code selection entails

  6. Facilitated charge transport in ternary interconnected electrodes for flexible supercapacitors with excellent power characteristics.

    Science.gov (United States)

    Chen, Wanjun; He, Yongmin; Li, Xiaodong; Zhou, Jinyuan; Zhang, Zhenxing; Zhao, Changhui; Gong, Chengshi; Li, Shuankui; Pan, Xiaojun; Xie, Erqing

    2013-12-07

    Flexible and high performance supercapacitors are very critical in modern society. In order to develop the flexible supercapacitors with high power density, free-standing and flexible three-dimensional graphene/carbon nanotubes/MnO2 (3DG/CNTs/MnO2) composite electrodes with interconnected ternary 3D structures were fabricated, and the fast electron and ion transport channels were effectively constructed in the rationally designed electrodes. Consequently, the obtained 3DG/CNTs/MnO2 composite electrodes exhibit superior specific capacitance and rate capability compared to 3DG/MnO2 electrodes. Furthermore, the 3DG/CNTs/MnO2 based asymmetric supercapacitor demonstrates the maximum energy and power densities of 33.71 W h kg(-1) and up to 22,727.3 W kg(-1), respectively. Moreover, the asymmetric supercapacitor exhibits excellent cycling stability with 95.3% of the specific capacitance maintained after 1000 cycle tests. Our proposed synthesis strategy to construct the novel ternary 3D structured electrodes can be efficiently applied to other high performance energy storage/conversion systems.

  7. Stimulation of the subthalamic region facilitates the selection and inhibition of motor responses in Parkinson's disease

    NARCIS (Netherlands)

    van den Wildenberg, Wery P. M.; van Boxtel, Geert J. M.; van der Molen, Maurits W.; Bosch, D. Andries; Speelman, Johannes D.; Brunia, Cornelis H. M.

    2006-01-01

    The aim of the present study was to specify the involvement of the basal ganglia in motor response selection and response inhibition. Two samples were studied. The first sample consisted of patients diagnosed with Parkinson's disease (PD) who received deep-brain stimulation (DBS) of the subthalamic

  8. Predictive distractor context facilitates attentional selection of high, but not intermediate and low, salience targets.

    Science.gov (United States)

    Töllner, Thomas; Conci, Markus; Müller, Hermann J

    2015-03-01

    It is well established that we can focally attend to a specific region in visual space without shifting our eyes, so as to extract action-relevant sensory information from covertly attended locations. The underlying mechanisms that determine how fast we engage our attentional spotlight in visual-search scenarios, however, remain controversial. One dominant view advocated by perceptual decision-making models holds that the times taken for focal-attentional selection are mediated by an internal template that biases perceptual coding and selection decisions exclusively through target-defining feature coding. This notion directly predicts that search times remain unaffected whether or not participants can anticipate the upcoming distractor context. Here we tested this hypothesis by employing an illusory-figure localization task that required participants to search for an invariant target amongst a variable distractor context, which gradually changed--either randomly or predictably--as a function of distractor-target similarity. We observed a graded decrease in internal focal-attentional selection times--correlated with external behavioral latencies--for distractor contexts of higher relative to lower similarity to the target. Critically, for low but not intermediate and high distractor-target similarity, these context-driven effects were cortically and behaviorally amplified when participants could reliably predict the type of distractors. This interactive pattern demonstrates that search guidance signals can integrate information about distractor, in addition to target, identities to optimize distractor-target competition for focal-attentional selection. © 2014 Wiley Periodicals, Inc.

  9. Effect of stochastic gating on channel-facilitated transport of non-interacting and strongly repelling solutes

    Science.gov (United States)

    Berezhkovskii, Alexander M.; Bezrukov, Sergey M.

    2017-08-01

    Ligand- or voltage-driven stochastic gating—the structural rearrangements by which the channel switches between its open and closed states—is a fundamental property of biological membrane channels. Gating underlies the channel's ability to respond to different stimuli and, therefore, to be functionally regulated by the changing environment. The accepted understanding of the gating effect on the solute flux through the channel is that the mean flux is the product of the flux through the open channel and the probability of finding the channel in the open state. Here, using a diffusion model of channel-facilitated transport, we show that this is true only when the gating is much slower than the dynamics of solute translocation through the channel. If this condition breaks, the mean flux could differ from this simple estimate by orders of magnitude.

  10. Selective visual scaling of time-scale processes facilitates broadband learning of isometric force frequency tracking.

    Science.gov (United States)

    King, Adam C; Newell, Karl M

    2015-10-01

    The experiment investigated the effect of selectively augmenting faster time scales of visual feedback information on the learning and transfer of continuous isometric force tracking tasks to test the generality of the self-organization of 1/f properties of force output. Three experimental groups tracked an irregular target pattern either under a standard fixed gain condition or with selectively enhancement in the visual feedback display of intermediate (4-8 Hz) or high (8-12 Hz) frequency components of the force output. All groups reduced tracking error over practice, with the error lowest in the intermediate scaling condition followed by the high scaling and fixed gain conditions, respectively. Selective visual scaling induced persistent changes across the frequency spectrum, with the strongest effect in the intermediate scaling condition and positive transfer to novel feedback displays. The findings reveal an interdependence of the timescales in the learning and transfer of isometric force output frequency structures consistent with 1/f process models of the time scales of motor output variability.

  11. Multi-omics facilitated variable selection in Cox-regression model for cancer prognosis prediction.

    Science.gov (United States)

    Liu, Cong; Wang, Xujun; Genchev, Georgi Z; Lu, Hui

    2017-07-15

    New developments in high-throughput genomic technologies have enabled the measurement of diverse types of omics biomarkers in a cost-efficient and clinically-feasible manner. Developing computational methods and tools for analysis and translation of such genomic data into clinically-relevant information is an ongoing and active area of investigation. For example, several studies have utilized an unsupervised learning framework to cluster patients by integrating omics data. Despite such recent advances, predicting cancer prognosis using integrated omics biomarkers remains a challenge. There is also a shortage of computational tools for predicting cancer prognosis by using supervised learning methods. The current standard approach is to fit a Cox regression model by concatenating the different types of omics data in a linear manner, while penalty could be added for feature selection. A more powerful approach, however, would be to incorporate data by considering relationships among omics datatypes. Here we developed two methods: a SKI-Cox method and a wLASSO-Cox method to incorporate the association among different types of omics data. Both methods fit the Cox proportional hazards model and predict a risk score based on mRNA expression profiles. SKI-Cox borrows the information generated by these additional types of omics data to guide variable selection, while wLASSO-Cox incorporates this information as a penalty factor during model fitting. We show that SKI-Cox and wLASSO-Cox models select more true variables than a LASSO-Cox model in simulation studies. We assess the performance of SKI-Cox and wLASSO-Cox using TCGA glioblastoma multiforme and lung adenocarcinoma data. In each case, mRNA expression, methylation, and copy number variation data are integrated to predict the overall survival time of cancer patients. Our methods achieve better performance in predicting patients' survival in glioblastoma and lung adenocarcinoma. Copyright © 2017. Published by Elsevier

  12. Auditory Selective Attention: an introduction and evidence for distinct facilitation and inhibition mechanisms

    OpenAIRE

    Mikyska, Constanze Elisabeth Anna

    2012-01-01

    Objective Auditory selective attention is a complex brain function that is still not completely understood. The classic example is the so-called “cocktail party effect” (Cherry, 1953), which describes the impressive ability to focus one’s attention on a single voice from a multitude of voices. This means that particular stimuli in the environment are enhanced in contrast to other ones of lower priority that are ignored. To be able to understand how attention can influence the perception and p...

  13. Highly selective BSA imprinted polyacrylamide hydrogels facilitated by a metal-coding MIP approach.

    Science.gov (United States)

    El-Sharif, H F; Yapati, H; Kalluru, S; Reddy, S M

    2015-12-01

    We report the fabrication of metal-coded molecularly imprinted polymers (MIPs) using hydrogel-based protein imprinting techniques. A Co(II) complex was prepared using (E)-2-((2 hydrazide-(4-vinylbenzyl)hydrazono)methyl)phenol; along with iron(III) chloroprotoporphyrin (Hemin), vinylferrocene (VFc), zinc(II) protoporphyrin (ZnPP) and protoporphyrin (PP), these complexes were introduced into the MIPs as co-monomers for metal-coding of non-metalloprotein imprints. Results indicate a 66% enhancement for bovine serum albumin (BSA) protein binding capacities (Q, mg/g) via metal-ion/ligand exchange properties within the metal-coded MIPs. Specifically, Co(II)-complex-based MIPs exhibited 92 ± 1% specific binding with Q values of 5.7 ± 0.45 mg BSA/g polymer and imprinting factors (IF) of 14.8 ± 1.9 (MIP/non-imprinted (NIP) control). The selectivity of our Co(II)-coded BSA MIPs were also tested using bovine haemoglobin (BHb), lysozyme (Lyz), and trypsin (Tryp). By evaluating imprinting factors (K), each of the latter proteins was found to have lower affinities in comparison to cognate BSA template. The hydrogels were further characterised by thermal analysis and differential scanning calorimetry (DSC) to assess optimum polymer composition. The development of hydrogel-based molecularly imprinted polymer (HydroMIPs) technology for the memory imprinting of proteins and for protein biosensor development presents many possibilities, including uses in bio-sample clean-up or selective extraction, replacement of biological antibodies in immunoassays and biosensors for medicine and the environment. Biosensors for proteins and viruses are currently expensive to develop because they require the use of expensive antibodies. Because of their biomimicry capabilities (and their potential to act as synthetic antibodies), HydroMIPs potentially offer a route to the development of new low-cost biosensors. Herein, a metal ion-mediated imprinting approach was employed to metal-code our

  14. Cation diffusion facilitators transport initiation and regulation is mediated by cation induced conformational changes of the cytoplasmic domain.

    Directory of Open Access Journals (Sweden)

    Natalie Zeytuni

    Full Text Available Cation diffusion facilitators (CDF are part of a highly conserved protein family that maintains cellular divalent cation homeostasis in all domains of life. CDF's were shown to be involved in several human diseases, such as Type-II diabetes and neurodegenerative diseases. In this work, we employed a multi-disciplinary approach to study the activation mechanism of the CDF protein family. For this we used MamM, one of the main ion transporters of magnetosomes--bacterial organelles that enable magnetotactic bacteria to orientate along geomagnetic fields. Our results reveal that the cytosolic domain of MamM forms a stable dimer that undergoes distinct conformational changes upon divalent cation binding. MamM conformational change is associated with three metal binding sites that were identified and characterized. Altogether, our results provide a novel auto-regulation mode of action model in which the cytosolic domain's conformational changes upon ligand binding allows the priming of the CDF into its transport mode.

  15. Colloid-Facilitated Transport of 137Cs in Fracture-Fill Material. Experiments and Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Dittrich, Timothy M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reimus, Paul William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-10-29

    In this study, we demonstrate how a combination of batch sorption/desorption experiments and column transport experiments were used to effectively parameterize a model describing the colloid-facilitated transport of Cs in the Grimsel granodiorite/FFM system. Cs partition coefficient estimates onto both the colloids and the stationary media obtained from the batch experiments were used as initial estimates of partition coefficients in the column experiments, and then the column experiment results were used to obtain refined estimates of the number of different sorption sites and the adsorption and desorption rate constants of the sites. The desorption portion of the column breakthrough curves highlighted the importance of accounting for adsorption-desorption hysteresis (or a very nonlinear adsorption isotherm) of the Cs on the FFM in the model, and this portion of the breakthrough curves also dictated that there be at least two different types of sorption sites on the FFM. In the end, the two-site model parameters estimated from the column experiments provided excellent matches to the batch adsorption/desorption data, which provided a measure of assurance in the validity of the model.

  16. Additive effects of emotional content and spatial selective attention on electrocortical facilitation.

    Science.gov (United States)

    Keil, Andreas; Moratti, Stephan; Sabatinelli, Dean; Bradley, Margaret M; Lang, Peter J

    2005-08-01

    Affectively arousing visual stimuli have been suggested to automatically attract attentional resources in order to optimize sensory processing. The present study crosses the factors of spatial selective attention and affective content, and examines the relationship between instructed (spatial) and automatic attention to affective stimuli. In addition to response times and error rate, electroencephalographic data from 129 electrodes were recorded during a covert spatial attention task. This task required silent counting of random-dot targets embedded in a 10 Hz flicker of colored pictures presented to both hemifields. Steady-state visual evoked potentials (ssVEPs) were obtained to determine amplitude and phase of electrocortical responses to pictures. An increase of ssVEP amplitude was observed as an additive function of spatial attention and emotional content. Statistical parametric mapping of this effect indicated occipito-temporal and parietal cortex activation contralateral to the attended visual hemifield in ssVEP amplitude modulation. This difference was most pronounced during selection of the left visual hemifield, at right temporal electrodes. In line with this finding, phase information revealed accelerated processing of aversive arousing, compared to affectively neutral pictures. The data suggest that affective stimulus properties modulate the spatiotemporal process along the ventral stream, encompassing amplitude amplification and timing changes of posterior and temporal cortex.

  17. Spatial learning in the 5-HT1B receptor knockout mouse: selective facilitation/impairment depending on the cognitive demand.

    Science.gov (United States)

    Buhot, Marie-Christine; Wolff, Mathieu; Benhassine, Narimane; Costet, Pierre; Hen, René; Segu, Louis

    2003-01-01

    Age-related memory decline is associated with a combined dysfunction of the cholinergic and serotonergic systems in the hippocampus and frontal cortex, in particular. The 5-HT1B receptor occupies strategic cellular and subcellular locations in these structures, where it plays a role in the modulation of ACh release. In an attempt to characterize the contribution of this receptor to memory functions, 5-HT1B receptor knockout (KO) mice were submitted to various behavioral paradigms carried out in the same experimental context (water maze), which were aimed at exposing mice to various levels of memory demand. 5-HT1BKO mice exhibited a facilitation in the acquisition of a hippocampal-dependent spatial reference memory task in the Morris water maze. This facilitation was selective of task difficulty, showing thus that the genetic inactivation of the 5-HT1B receptor is associated with facilitation when the complexity of the task is increased, and reveals a protective effect on age-related hippocampal-dependent memory decline. Young-adult and aged KO and wild-type (WT) mice were equally able to learn a delayed spatial matching-to-sample working memory task in a radial-arm water maze with short (0 or 5 min) delays. However, 5-HT1BKO mice, only, exhibited a selective memory impairment at intermediate and long (15, 30, and 60 min) delays. Treatment by scopolamine induced the same pattern of performance in wild type as did the mutation for short (5 min, no impairment) and long (60 min, impairment) delays. Taken together, these studies revealed a beneficial effect of the mutation on the acquisition of a spatial reference memory task, but a deleterious effect on a working memory task for long delays. This 5-HT1BKO mouse story highlights the problem of the potential existence of "global memory enhancers."

  18. Facilitating the selection and creation of accurate interatomic potentials with robust tools and characterization

    Science.gov (United States)

    Trautt, Zachary T.; Tavazza, Francesca; Becker, Chandler A.

    2015-10-01

    The Materials Genome Initiative seeks to significantly decrease the cost and time of development and integration of new materials. Within the domain of atomistic simulations, several roadblocks stand in the way of reaching this goal. While the NIST Interatomic Potentials Repository hosts numerous interatomic potentials (force fields), researchers cannot immediately determine the best choice(s) for their use case. Researchers developing new potentials, specifically those in restricted environments, lack a comprehensive portfolio of efficient tools capable of calculating and archiving the properties of their potentials. This paper elucidates one solution to these problems, which uses Python-based scripts that are suitable for rapid property evaluation and human knowledge transfer. Calculation results are visible on the repository website, which reduces the time required to select an interatomic potential for a specific use case. Furthermore, property evaluation scripts are being integrated with modern platforms to improve discoverability and access of materials property data. To demonstrate these scripts and features, we will discuss the automation of stacking fault energy calculations and their application to additional elements. While the calculation methodology was developed previously, we are using it here as a case study in simulation automation and property calculations. We demonstrate how the use of Python scripts allows for rapid calculation in a more easily managed way where the calculations can be modified, and the results presented in user-friendly and concise ways. Additionally, the methods can be incorporated into other efforts, such as openKIM.

  19. Facilitating the selection and creation of accurate interatomic potentials with robust tools and characterization

    International Nuclear Information System (INIS)

    Trautt, Zachary T; Tavazza, Francesca; Becker, Chandler A

    2015-01-01

    The Materials Genome Initiative seeks to significantly decrease the cost and time of development and integration of new materials. Within the domain of atomistic simulations, several roadblocks stand in the way of reaching this goal. While the NIST Interatomic Potentials Repository hosts numerous interatomic potentials (force fields), researchers cannot immediately determine the best choice(s) for their use case. Researchers developing new potentials, specifically those in restricted environments, lack a comprehensive portfolio of efficient tools capable of calculating and archiving the properties of their potentials. This paper elucidates one solution to these problems, which uses Python-based scripts that are suitable for rapid property evaluation and human knowledge transfer. Calculation results are visible on the repository website, which reduces the time required to select an interatomic potential for a specific use case. Furthermore, property evaluation scripts are being integrated with modern platforms to improve discoverability and access of materials property data. To demonstrate these scripts and features, we will discuss the automation of stacking fault energy calculations and their application to additional elements. While the calculation methodology was developed previously, we are using it here as a case study in simulation automation and property calculations. We demonstrate how the use of Python scripts allows for rapid calculation in a more easily managed way where the calculations can be modified, and the results presented in user-friendly and concise ways. Additionally, the methods can be incorporated into other efforts, such as openKIM. (paper)

  20. TRANSPORT CHARACTERISTICS OF SELECTED PWR LOCA GENERATED DEBRIS

    International Nuclear Information System (INIS)

    MAJI, A. K.; MARSHALL, B.

    2000-01-01

    In the unlikely event of a Loss of Coolant Accident (LOCA) in a pressurized water reactor (PWR), break jet impingement would dislodge thermal insulation FR-om nearby piping, as well as other materials within the containment, such as paint chips, concrete dust, and fire barrier materials. Steam/water flows induced by the break and by the containment sprays would transport debris to the containment floor. Subsequently, debris would likely transport to and accumulate on the suction sump screens of the emergency core cooling system (ECCS) pumps, thereby potentially degrading ECCS performance and possibly even failing the ECCS. In 1998, the U. S. Nuclear Regulatory Commission (NRC) initiated a generic study (Generic Safety Issue-191) to evaluate the potential for the accumulation of LOCA related debris on the PWR sump screen and the consequent loss of ECCS pump net positive suction head (NPSH). Los Alamos National Laboratory (LANL), supporting the resolution of GSI-191, was tasked with developing a method for estimating debris transport in PWR containments to estimate the quantity of debris that would accumulate on the sump screen for use in plant specific evaluations. The analytical method proposed by LANL, to predict debris transport within the water that would accumulate on the containment floor, is to use computational fluid dynamics (CFD) combined with experimental debris transport data to predict debris transport and accumulation on the screen. CFD simulations of actual plant containment designs would provide flow data for a postulated accident in that plant, e.g., three-dimensional patterns of flow velocities and flow turbulence. Small-scale experiments would determine parameters defining the debris transport characteristics for each type of debris. The containment floor transport methodology will merge debris transport characteristics with CFD results to provide a reasonable and conservative estimate of debris transport within the containment floor pool and

  1. The Methodology of Selecting the Transport Mode for Companies on the Slovak Transport Market

    Directory of Open Access Journals (Sweden)

    Černá Lenka

    2017-03-01

    Full Text Available Transport volume in the Slovak Republic is growing continuously every year. This rising trend is influenced by the development of car industry and its suppliers. Slovak republic has also a geographic strategy position in middle Europe from the side of transport corridors (east-west and north-south. The development of transport volume in freight transport depends on the transport and business processes between the European Union and China and it is an opportunity for Slovak republic to obtain transit transport flows.

  2. Technetium migration in Boom Clay - Assessing the role of colloid-facilitated transport in a deep clay formation

    International Nuclear Information System (INIS)

    Bruggeman, C.; Martens, E.; Maes, N.; Jacops, E.; Van Gompel, M.; Van Ravestyn, L.

    2010-01-01

    independent study on the migration of natural organic matter was used to extract migration parameters. This independent study relied on both lab-scale and in situ large-scale migration experiments with 14 C-labelled NOM which were performed over a period of 15 years. A classic diffusion-advection equation, including a colloid filtration term and/or non-linear sorption, simulated the experimental data quite well and could also account for the anisotropy of the Boom Clay formation. By using information from independent experiments on processes that were assumed to occur upon transport of Tc through the Boom Clay formation, the degree of freedom of the model was seriously constrained. All parameters used in the reactive transport model (Tc solubility, complexation with inorganic ligands, stability constant for the 'colloid-colloid' interaction process, solid-solution distribution coefficient of aqueous inorganic Tc species) were either taken from established thermodynamic data sources, or from published data of batch experiments. Only the first-order kinetic rate that accounted for slow decoupling of the Tc colloid and the organic matter colloids was fitted. An accurate model simulation could be obtained both for the Tc concentration in the outflowing solution, and the Tc tracer profile across the clay cores used in the setup. The good accuracy between the reactive transport model, batch experimental data and the experimental percolation data shows that the conceptual model is strong enough to handle different types of experimental setups, and allows to make interpolations for different geochemical conditions. Moreover, the model was adapted to make predictions of Tc migration as a NOM-associated colloid over the entire height of the overlying formation. Based on these predictions, we are now able to assess the potential for colloid-facilitated transport of radionuclides by dissolved NOM in Boom Clay. (authors)

  3. Nicotine facilitates nicotinic acetylcholine receptor targeting to mitochondria but makes them less susceptible to selective ligands.

    Science.gov (United States)

    Uspenska, Kateryna; Lykhmus, Olena; Gergalova, Galyna; Chernyshov, Volodymyr; Arias, Hugo R; Komisarenko, Sergiy; Skok, Maryna

    2017-08-24

    Several nicotinic acetylcholine receptor (nAChR) subtypes are expressed in mitochondria to regulate the internal pathway of apoptosis in ion channel-independent manner. However, the mechanisms of nAChR activation in mitochondria and targeting to mitochondria are still unknown. Nicotine has been shown to favor nAChR pentamer assembly, folding, and maturation on the way of biosynthesis. The idea of the present work was to determine whether nicotine affects the content, glycosylation, and function of mitochondrial nAChRs. Experiments were performed in isolated liver mitochondria from mice, that either consumed or not nicotine with the drinking water (200μL/L) for 7days. Mitochondria detergent lysates were studied by sandwich or lectin ELISA for the presence and carbohydrate composition of different nAChR subunits. Intact mitochondria were examined by flow cytometry for the binding of fluorescently labeled α-cobratoxin and were tested in functional assay of cytochrome c release under the effect of either Ca 2+ or wortmannin in the presence or absence of nAChR-selective ligands, including PNU-282987 (1nM), dihydro-β-erythroidine (DhβE, 1μM), PNU-120596 (0.3, 3, or 10μM) and desformylflustrabromine hydrochloride (dFBr, 0.001, 0.3, or 1μM). It was found that nicotine consumption increased the ratio of mitochondrial vs non-mitochondrial nAChRs in the liver, enhanced fucosylation of mitochondrial nAChRs, but prevented the binding of α-cobratoxin and the cytochrome c release-attenuating effects of nAChR-specific agonists, antagonists, or positive allosteric modulators. It is concluded that nicotine consumption in vivo favors nAChR glycosylation and trafficking to mitochondria but makes them less susceptible to the effects of specific ligands. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Hemispheric-scale wind selection facilitates bar-tailed godwit circum-migration of the Pacific

    Science.gov (United States)

    Gill, Robert E.; Douglas, David C.; Handel, Colleen M.; Tibbitts, T. Lee; Hufford, Gary; Piersma, Theunis

    2014-01-01

    The annual 29 000 km long migration of the bar-tailed godwit, Limosa lapponica baueri, around the Pacific Ocean traverses what is arguably the most complex and seasonally structured atmospheric setting on Earth. Faced with marked variation in wind regimes and storm conditions across oceanic migration corridors, individuals must make critical decisions about when and where to fly during nonstop flights of a week's duration or longer. At a minimum, their decisions will affect wind profitability and thus reduce energetic costs of migration; in the extreme, poor decisions or unpredictable weather events will risk survival. We used satellite telemetry to track the annual migration of 24 bar-tailed godwits and analysed their flight performance relative to wind conditions during three major migration legs between nonbreeding grounds in New Zealand and breeding grounds in Alaska. Because flight altitudes of birds en route were unknown, we modelled flight efficiency at six geopotential heights across each migratory segment. Birds selected departure dates when atmospheric conditions conferred the greatest wind assistance both at departure and throughout their flights. This behaviour suggests that there exists a cognitive mechanism, heretofore unknown among migratory birds, that allows godwits to assess changes in weather conditions that are linked (i.e. teleconnected) across widely separated atmospheric regions. Godwits also showed adaptive flexibility in their response not only to cues related to seasonal changes in macrometeorology, such as spatial shifting of storm tracks and temporal periods of cyclogenesis, but also to cues associated with stochastic events, especially at departure sites. Godwits showed limits to their response behaviours, however, especially relative to rapidly developing stochastic events while en route. We found that flight efficiency depended significantly upon altitude and hypothesize that godwits exhibit further adaptive flexibility by varying

  5. Electrostatics of aquaporin and aquaglyceroporin channels correlates with their transport selectivity

    Science.gov (United States)

    Oliva, Romina; Calamita, Giuseppe; Thornton, Janet M.; Pellegrini-Calace, Marialuisa

    2010-01-01

    Aquaporins are homotetrameric channel proteins, which allow the diffusion of water and small solutes across biological membranes. According to their transport function, aquaporins can be divided into “orthodox aquaporins”, which allow the flux of water molecules only, and “aquaglyceroporins”, which facilitate the diffusion of glycerol and other small solutes in addition to water. The contribution of individual residues in the pore to the selectivity of orthodox aquaporins and aquaglyceroporins is not yet fully understood. To gain insights into aquaporin selectivity, we focused on the sequence variation and electrostatics of their channels. The continuum Poisson-Boltzmann electrostatic potential along the channel was calculated and compared for ten three-dimensional-structures which are representatives of different aquaporin subfamilies, and a panel of functionally characterized mutants, for which high-accuracy three-dimensional-models could be derived. Interestingly, specific electrostatic profiles associated with the main selectivity to water or glycerol could be identified. In particular: (i) orthodox aquaporins showed a distinctive electrostatic potential maximum at the periplasmic side of the channel around the aromatic/Arg (ar/R) constriction site; (ii) aquaporin-0 (AQP0), a mammalian aquaporin with considerably low water permeability, had an additional deep minimum at the cytoplasmic side; (iii) aquaglyceroporins showed a rather flat potential all along the channel; and (iv) the bifunctional protozoan PfAQP had an unusual all negative profile. Evaluation of electrostatics of the mutants, along with a thorough sequence analysis of the aquaporin pore-lining residues, illuminated the contribution of specific residues to the electrostatics of the channels and possibly to their selectivity. PMID:20147624

  6. Proton transport facilitating water-oxidation: the role of second sphere ligands surrounding the catalytic metal cluster.

    Science.gov (United States)

    Bao, Han; Dilbeck, Preston L; Burnap, Robert L

    2013-10-01

    The ability of PSII to extract electrons from water, with molecular oxygen as a by-product, is a remarkable biochemical and evolutionary innovation. From an evolutionary perspective, the invention of PSII approximately 2.7 Ga led to the accelerated accumulation of biomass in the biosphere and the accumulation of oxygen in the atmosphere, a combination that allowed for the evolution of a much more complex and extensive biosphere than would otherwise have been possible. From the biochemical and enzymatic perspective, PSII is remarkable because of the thermodynamic and kinetic obstacles that needed to have been overcome to oxidize water as the ultimate photosynthetic electron donor. This article focuses on how proton release is an integral part of how these kinetic and thermodynamic obstacles have been overcome: the sequential removal of protons from the active site of H2O-oxidation facilitates the multistep oxidation of the substrate water at the Mn4CaOx, the catalytic heart of the H2O-oxidation reaction. As noted previously, the facilitated deprotonation of the Mn4CaOx cluster exerts a redox-leveling function preventing the accumulation of excess positive charge on the cluster, which might otherwise hinder the already energetically difficult oxidation of water. Using recent results, including the characteristics of site-directed mutants, the role of the second sphere of amino acid ligands and the associated network of water molecules surrounding the Mn4CaOx is discussed in relation to proton transport in other systems. In addition to the redox-leveling function, a trapping function is assigned to the proton release step occurring immediately prior to the dioxygen chemistry. This trapping appears to involve a yet-to-be clarified gating mechanism that facilitates to coordinated release of a proton from the neighborhood of the active site thereby insuring that the backward charge-recombination reaction does not out-compete the forward reaction of dioxygen chemistry

  7. Foxp3(+) T cells regulate immunoglobulin a selection and facilitate diversification of bacterial species responsible for immune homeostasis.

    Science.gov (United States)

    Kawamoto, Shimpei; Maruya, Mikako; Kato, Lucia M; Suda, Wataru; Atarashi, Koji; Doi, Yasuko; Tsutsui, Yumi; Qin, Hongyan; Honda, Kenya; Okada, Takaharu; Hattori, Masahira; Fagarasan, Sidonia

    2014-07-17

    Foxp3(+) T cells play a critical role for the maintenance of immune tolerance. Here we show that in mice, Foxp3(+) T cells contributed to diversification of gut microbiota, particularly of species belonging to Firmicutes. The control of indigenous bacteria by Foxp3(+) T cells involved regulatory functions both outside and inside germinal centers (GCs), consisting of suppression of inflammation and regulation of immunoglobulin A (IgA) selection in Peyer's patches, respectively. Diversified and selected IgAs contributed to maintenance of diversified and balanced microbiota, which in turn facilitated the expansion of Foxp3(+) T cells, induction of GCs, and IgA responses in the gut through a symbiotic regulatory loop. Thus, the adaptive immune system, through cellular and molecular components that are required for immune tolerance and through the diversification as well as selection of antibody repertoire, mediates host-microbial symbiosis by controlling the richness and balance of bacterial communities required for homeostasis. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Progress report on colloid-facilitated transport at Yucca Mountain: Yucca Mountain site characterization program milestone 3383

    International Nuclear Information System (INIS)

    Triay, I.R.; Degueldre, C.; Wistrom, A.O.; Cotter, C.R.; Lemons, W.W.

    1996-06-01

    To assess colloid-facilitated radionuclide transport in groundwaters at the potential nuclear waste repository at Yucca Mountain, it is very important to understand the generation and stability of colloids, including naturally occurring colloids. To this end, we measured the colloid concentration in waters from Well J-13, which is on the order of 106 particles per milliliter (for particle sizes larger than 100 manometers). At this low particle loading, the sorption of radionuclides to colloids would have to be extremely high before the colloids could carry a significant amount of radionuclides from the repository to the accessible environment. We also performed aggregation experiments to evaluate the stability of silica (particle diameter: 85 nm) and clay colloids (particle diameter: 140 nm) as a function of ionic strength in a carbonate-rich synthetic groundwater. When the concentration of electrolyte is increased to induce aggregation, the aggregation is irreversible and the rate of aggregation increases with increasing electrolyte strength. We used autocorrelation photon spectroscopy to estimate the rate of particle aggregation for both types of colloids. By relating the measured aggregation rate to the Smoluchowski rate expression, we determined the stability ratio, W. Aggregation of silica particles and kaolinite clay particles decreased dramatically for an electrolyte concentration, C NaCl , below 300 mM and 200 mM, respectively

  9. Preparation of a Facilitated Transport Membrane Composed of Carboxymethyl Chitosan and Polyethylenimine for CO2/N2 Separation

    Directory of Open Access Journals (Sweden)

    Jiang-Nan Shen

    2013-02-01

    Full Text Available The miscibility of carboxymethyl chitosan/polyethylenimine (CMCS/PEI blends was analyzed by FT-IR, TGA and SEM. Defect-free CMCS/PEI blend membranes were prepared with polysulfone (PSf ultrafiltration membranes as support layer for the separation of CO2/N2 mixtures. The results demonstrate that the CMCS/PEI blend is miscible, due to the hydrogen bonding interaction between the two targeted polymers. For the blended membrane without water, the permeability of CO2 gas is 3.6 × 10−7 cm3 cm−2 s−1 cmHg−1 and the corresponding separation factor for CO2 and N2 gas is about 33 at the pressure of 15.2 cmHg. Meanwhile, the blended membrane with water has the better permselectivity. The blended membrane containing water with PEI content of 30 wt% has the permeance of 6.3 × 10−4 cm3 cm−2 s−1 cmHg−1 for CO2 gas and a separation factor of 325 for CO2/N2 mixtures at the same feed pressure. This indicates that the CO2 separation performance of the CMCS/PEI blend membrane is higher than that of other facilitated transport membranes reported for CO2/N2 mixture separation.

  10. A New Natural Product Analog of Blasticidin S Reveals Cellular Uptake Facilitated by the NorA Multidrug Transporter.

    Science.gov (United States)

    Davison, Jack R; Lohith, Katheryn M; Wang, Xiaoning; Bobyk, Kostyantyn; Mandadapu, Sivakoteswara R; Lee, Su-Lin; Cencic, Regina; Nelson, Justin; Simpkins, Scott; Frank, Karen M; Pelletier, Jerry; Myers, Chad L; Piotrowski, Jeff; Smith, Harold E; Bewley, Carole A

    2017-06-01

    The permeation of antibiotics through bacterial membranes to their target site is a crucial determinant of drug activity but in many cases remains poorly understood. During screening efforts to discover new broad-spectrum antibiotic compounds from marine sponge samples, we identified a new analog of the peptidyl nucleoside antibiotic blasticidin S that exhibited up to 16-fold-improved potency against a range of laboratory and clinical bacterial strains which we named P10. Whole-genome sequencing of laboratory-evolved strains of Staphylococcus aureus resistant to blasticidin S and P10, combined with genome-wide assessment of the fitness of barcoded Escherichia coli knockout strains in the presence of the antibiotics, revealed that restriction of cellular access was a key feature in the development of resistance to this class of drug. In particular, the gene encoding the well-characterized multidrug efflux pump NorA was found to be mutated in 69% of all S. aureus isolates resistant to blasticidin S or P10. Unexpectedly, resistance was associated with inactivation of norA , suggesting that the NorA transporter facilitates cellular entry of peptidyl nucleosides in addition to its known role in the efflux of diverse compounds, including fluoroquinolone antibiotics. Copyright © 2017 American Society for Microbiology.

  11. Dual and Direction-Selective Mechanisms of Phosphate Transport by the Vesicular Glutamate Transporter

    Directory of Open Access Journals (Sweden)

    Julia Preobraschenski

    2018-04-01

    Full Text Available Summary: Vesicular glutamate transporters (VGLUTs fill synaptic vesicles with glutamate and are thus essential for glutamatergic neurotransmission. However, VGLUTs were originally discovered as members of a transporter subfamily specific for inorganic phosphate (Pi. It is still unclear how VGLUTs accommodate glutamate transport coupled to an electrochemical proton gradient ΔμH+ with inversely directed Pi transport coupled to the Na+ gradient and the membrane potential. Using both functional reconstitution and heterologous expression, we show that VGLUT transports glutamate and Pi using a single substrate binding site but different coupling to cation gradients. When facing the cytoplasm, both ions are transported into synaptic vesicles in a ΔμH+-dependent fashion, with glutamate preferred over Pi. When facing the extracellular space, Pi is transported in a Na+-coupled manner, with glutamate competing for binding but at lower affinity. We conclude that VGLUTs have dual functions in both vesicle transmitter loading and Pi homeostasis within glutamatergic neurons. : Preobraschenski et al. show that the vesicular glutamate transporter functions as a bi-directional phosphate transporter that is coupled with different cations in each direction and hence may play a key role in neuronal phosphate homeostasis. Keywords: VGLUT, SLC17 family, type I Na+-dependent inorganic phosphate transporter, ATPase, proteoliposomes, hybrid vesicles, anti-VGLUT1 nanobody

  12. Sequential algorithm analysis to facilitate selective biliary access for difficult biliary cannulation in ERCP: a prospective clinical study.

    Science.gov (United States)

    Lee, Tae Hoon; Hwang, Soon Oh; Choi, Hyun Jong; Jung, Yunho; Cha, Sang Woo; Chung, Il-Kwun; Moon, Jong Ho; Cho, Young Deok; Park, Sang-Heum; Kim, Sun-Joo

    2014-02-17

    Numerous clinical trials to improve the success rate of biliary access in difficult biliary cannulation (DBC) during ERCP have been reported. However, standard guidelines or sequential protocol analysis according to different methods are limited in place. We planned to investigate a sequential protocol to facilitate selective biliary access for DBC during ERCP. This prospective clinical study enrolled 711 patients with naïve papillae at a tertiary referral center. If wire-guided cannulation was deemed to have failed due to the DBC criteria, then according to the cannulation algorithm early precut fistulotomy (EPF; cannulation time > 5 min, papillary contacts > 5 times, or hook-nose-shaped papilla), double-guidewire cannulation (DGC; unintentional pancreatic duct cannulation ≥ 3 times), and precut after placement of a pancreatic stent (PPS; if DGC was difficult or failed) were performed sequentially. The main outcome measurements were the technical success, procedure outcomes, and complications. Initially, a total of 140 (19.7%) patients with DBC underwent EPF (n = 71) and DGC (n = 69). Then, in DGC group 36 patients switched to PPS due to difficulty criteria. The successful biliary cannulation rate was 97.1% (136/140; 94.4% [67/71] with EPF, 47.8% [33/69] with DGC, and 100% [36/36] with PPS; P EPF, 314.8 (65.2) seconds in DGC, and 706.0 (469.4) seconds in PPS (P EPF, DGC, and PPS may be safe and feasible for DBC. The use of EPF in selected DBC criteria, DGC in unintentional pancreatic duct cannulations, and PPS in failed or difficult DGC may facilitate successful biliary cannulation.

  13. Selecting The Best Initial Method For A Transportation Problem ...

    African Journals Online (AJOL)

    This paper is concerned with determining the best initial method for a transportation problem. Seven initial methods are considered and compared. One is a new method that has not been reported in the literature. Comparison is done on the basis of the number of iterations required to reach the final solution if the concerned ...

  14. Selected Topics on Mass Transport in Gas-solid Interactions

    DEFF Research Database (Denmark)

    Somers, Marcel A.J.

    2004-01-01

    The present article is a short review containing examples of the role of mass transport in the solid state during gas-solid interactions. Examples are taken from the authors' research on the interaction of carbon and/or nitrogen with iron-based metals. Topics dealt with are diffusion-controlled d......The present article is a short review containing examples of the role of mass transport in the solid state during gas-solid interactions. Examples are taken from the authors' research on the interaction of carbon and/or nitrogen with iron-based metals. Topics dealt with are diffusion...... on the kinetics of phenomena in the solid state. Various experimental techniques were applied to investigate these phenomena; it is however beyond the scope of the present article to treat experimental conditions in detail. The interested reader is referred to the original work for in depth discussions...

  15. Membranes with functionalized carbon nanotube pores for selective transport

    Science.gov (United States)

    Bakajin, Olgica; Noy, Aleksandr; Fornasiero, Francesco; Park, Hyung Gyu; Holt, Jason K; Kim, Sangil

    2015-01-27

    Provided herein composition and methods for nanoporous membranes comprising single walled, double walled, or multi-walled carbon nanotubes embedded in a matrix material. Average pore size of the carbon nanotube can be 6 nm or less. These membranes are a robust platform for the study of confined molecular transport, with applications in liquid and gas separations and chemical sensing including desalination, dialysis, and fabric formation.

  16. Evaluation of the Montana Department of Transportation's research project solicitation, prioritization, and selection process

    Science.gov (United States)

    2008-05-01

    The Montana Department of Transportation (MDT) contracted the Bureau of Business and Economic Research at the University of Montana Missoula to conduct research to determine how other states solicit, prioritize, and select research problem statem...

  17. GREY STATISTICS METHOD OF TECHNOLOGY SELECTION FOR ADVANCED PUBLIC TRANSPORTATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Chien Hung WEI

    2003-01-01

    Full Text Available Taiwan is involved in intelligent transportation systems planning, and is now selecting its prior focus areas for investment and development. The high social and economic impact associated with which intelligent transportation systems technology are chosen explains the efforts of various electronics and transportation corporations for developing intelligent transportation systems technology to expand their business opportunities. However, there has been no detailed research conducted with regard to selecting technology for advanced public transportation systems in Taiwan. Thus, the present paper demonstrates a grey statistics method integrated with a scenario method for solving the problem of selecting advanced public transportation systems technology for Taiwan. A comprehensive questionnaire survey was conducted to demonstrate the effectiveness of the grey statistics method. The proposed approach indicated that contactless smart card technology is the appropriate technology for Taiwan to develop in the near future. The significance of our research results implies that the grey statistics method is an effective method for selecting advanced public transportation systems technologies. We feel our information will be beneficial to the private sector for developing an appropriate intelligent transportation systems technology strategy.

  18. Selected risk factors of diabetes mellitus among road transport drivers.

    Science.gov (United States)

    Marcinkiewicz, Andrzej; Szosland, Dorota

    2010-01-01

    Road transport drivers are one of the professional groups whose activities have a strong impact on public safety. In view of the nature of their professional activity, the drivers are at a higher risk of obesity and hypertension, and thus, indirectly, of carbohydrate metabolism disorders such as diabetes mellitus. Medical documentation was a source of data for the reported study. It derived from medical examinations of truck and bus drivers applying for the new category II driving licence or for prolongation of the one they already had. Excessive body weight was recorded in 62.6% of the study population; 45.3% had overweight and 17.4% were diagnosed with obesity. Hypertension was noted in the medical records of 36.7% drivers. The prevalence of abnormal BP values was increasing with age. Overweight was found to be a risk factor for hypertension. Hyperglycaemia was found in 47.5% of the drivers and was also increasing with age. In road transport drivers, the high prevalence of excessive body weight and elevated arterial blood pressure as the risk factors for diabetes indicates a need to undertake multidimensional actions targeted on this particular profession and involving various health care sectors. Prophylactic and detailed pre-placement examinations should be considered, depending on the rate and intensity of the disorders diagnosed. This should be coupled with an introduction of primary and secondary prophylactic activities and monitoring of relevant treatment. A close collaboration with the patient's GP is necessary.

  19. Facilitated and selective oxidation of thiophenic sulfur compounds using MoOx/Al₂O₃-H₂O₂ system under ultrasonic irradiation.

    Science.gov (United States)

    Akbari, Azam; Omidkhah, Mohammadreza; Towfighi Darian, Jafar

    2015-03-01

    Oxidative desulfurization of thiophenic sulfur compounds of benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyl dibenzothiophene (4,6-DMDBT) with MoOx/Al₂O₃ catalyst and H₂O₂ oxidant has been facilitated and more selective under ultrasonic irradiation. The catalyst with the optimum 10% of Mo loading consisted of isolated tetrahedral molybdenum oxide species based on FTIR analysis. The increase of Mo loading to 15% and 20% caused to generation of polymolybdate and MoO₃ crystals which decreased desulfurization activity. Sonication enhanced the apparent reaction rate constants in oxidation of all three sulfur compounds. An increase in the Arrhenius factor (A0), which is the total number of collisions per second, could explain the acceleration in the rate constants by sonication. The apparent activated energy (Ea) of BT oxidation was reduced from 96.6 to 75.3 kJ/mol by using ultrasound. This indicated that ultrasound had also a chemical effect, like a catalytic influence, in the acceleration of BT removal. DBT oxidation was reduced when investigated in the presence of tetralin, naphthalene and 2-methyl naphthalene as the model aromatic compounds of actual light oils. A higher selectivity toward DBT elimination in the presence of aromatics was obtained by sonication when compared with the silent treatment. Ultrasound cleaned the catalyst surface from adsorbed aromatics. On the basis of the obtained results, a mechanistic proposal for this desulfurization was explained. Oxidation was performed by nucleophilic attack of sulfur atom to the molybdenum peroxide species of tetrahedral molybdates, which was more advanced by sonication. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Riders on the storm: selective tidal movements facilitate the spawning migration of threatened delta smelt in the San Francisco Estuary

    Science.gov (United States)

    Bennett, W.A.; Burau, Jon R.

    2015-01-01

    Migration strategies in estuarine fishes typically include behavioral adaptations for reducing energetic costs and mortality during travel to optimize reproductive success. The influence of tidal currents and water turbidity on individual movement behavior were investigated during the spawning migration of the threatened delta smelt, Hypomesus transpacificus, in the northern San Francisco Estuary, California, USA. Water current velocities and turbidity levels were measured concurrently with delta smelt occurrence at sites in the lower Sacramento River and San Joaquin River as turbidity increased due to first-flush winter rainstorms in January and December 2010. The presence/absence of fish at the shoal-channel interface and near the shoreline was quantified hourly over complete tidal cycles. Delta smelt were caught consistently at the shoal-channel interface during flood tides and near the shoreline during ebb tides in the turbid Sacramento River, but were rare in the clearer San Joaquin River. The apparent selective tidal movements by delta smelt would facilitate either maintaining position or moving upriver on flood tides, and minimizing advection down-estuary on ebb tides. These movements also may reflect responses to lateral gradients in water turbidity created by temporal lags in tidal velocities between the near-shore and mid-channel habitats. This migration strategy can minimize the energy spent swimming against strong river and tidal currents, as well as predation risks by remaining in turbid water. Selection pressure on individuals to remain in turbid water may underlie population-level observations suggesting that turbidity is a key habitat feature and cue initiating the delta smelt spawning migration.

  1. Novel Protic Ionic Liquid Composite Membranes with Fast and Selective Gas Transport Nanochannels for Ethylene/Ethane Separation.

    Science.gov (United States)

    Dou, Haozhen; Jiang, Bin; Xiao, Xiaoming; Xu, Mi; Tantai, Xiaowei; Wang, Baoyu; Sun, Yongli; Zhang, Luhong

    2018-04-25

    Protic ionic liquids (PILs) were utilized for the fabrication of composite membranes containing silver salt as the C 2 H 4 transport carrier to perform C 2 H 4 /C 2 H 6 separation for the first time. The intrinsic nanostructures of PILs were adopted to construct fast and selective C 2 H 4 transport nanochannels. The investigation of structure-performance relationships of composite membranes suggested that transport nanochannels (polar domains of PILs) could be tuned by the sizes of cations, which greatly manipulated activity of the carrier and determined the separation performances of membranes. The role of different carriers in the facilitated transport was studied, which revealed that the PILs were good solvents for dissolution and activation of the carrier due to their hydrogen bond networks and waterlike properties. The operating conditions of separation process were investigated systemically and optimized, confirming C 2 H 4 /C 2 H 6 selectivity was enhanced with the increase of silver salt concentration, the flow rate of sweep gas, and the feed ratio of C 2 H 4 to C 2 H 6 , as well as the decrease of the transmembrane pressure and operating temperature. Furthermore, the composite membranes exhibited long-term stability and obtained very competitive separation performances compared with other results. In summary, PIL composite membranes, which possess good long-term stability, high C 2 H 4 /C 2 H 6 selectivity, and excellent C 2 H 4 permeability, may have a good perspective in industrial C 2 H 4 /C 2 H 6 separation.

  2. Artificial membranes with selective nanochannels for protein transport

    KAUST Repository

    Sutisna, Burhannudin

    2016-09-05

    A poly(styrene-b-tert-butoxystyrene-b-styrene) copolymer was synthesized by anionic polymerization and hydrolyzed to poly(styrene-b-4-hydroxystyrene-b-styrene). Lamellar morphology was confirmed in the bulk after annealing. Membranes were fabricated by self-assembly of the hydrolyzed copolymer in solution, followed by water induced phase separation. A high density of pores of 4 to 5 nm diameter led to a water permeance of 40 L m−2 h−1 bar−1 and molecular weight cut-off around 8 kg mol−1. The morphology was controlled by tuning the polymer concentration, evaporation time, and the addition of imidazole and pyridine to stabilize the terpolymer micelles in the casting solution via hydrogen bond complexes. Transmission electron microscopy of the membrane cross-sections confirmed the formation of channels with hydroxyl groups beneficial for hydrogen-bond forming sites. The morphology evolution was investigated by time-resolved grazing incidence small angle X-ray scattering experiments. The membrane channels reject polyethylene glycol with a molecular size of 10 kg mol−1, but are permeable to proteins, such as lysozyme (14.3 kg mol−1) and cytochrome c (12.4 kg mol−1), due to the right balance of hydrogen bond interactions along the channels, electrostatic attraction, as well as the right pore sizes. Our results demonstrate that artificial channels can be designed for protein transport via block copolymer self-assembly using classical methods of membrane preparation.

  3. Artificial membranes with selective nanochannels for protein transport

    KAUST Repository

    Sutisna, Burhannudin; Polymeropoulos, Georgios; Mygiakis, E.; Musteata, Valentina-Elena; Peinemann, Klaus-Viktor; Smilgies, D. M.; Hadjichristidis, Nikolaos; Nunes, Suzana Pereira

    2016-01-01

    A poly(styrene-b-tert-butoxystyrene-b-styrene) copolymer was synthesized by anionic polymerization and hydrolyzed to poly(styrene-b-4-hydroxystyrene-b-styrene). Lamellar morphology was confirmed in the bulk after annealing. Membranes were fabricated by self-assembly of the hydrolyzed copolymer in solution, followed by water induced phase separation. A high density of pores of 4 to 5 nm diameter led to a water permeance of 40 L m−2 h−1 bar−1 and molecular weight cut-off around 8 kg mol−1. The morphology was controlled by tuning the polymer concentration, evaporation time, and the addition of imidazole and pyridine to stabilize the terpolymer micelles in the casting solution via hydrogen bond complexes. Transmission electron microscopy of the membrane cross-sections confirmed the formation of channels with hydroxyl groups beneficial for hydrogen-bond forming sites. The morphology evolution was investigated by time-resolved grazing incidence small angle X-ray scattering experiments. The membrane channels reject polyethylene glycol with a molecular size of 10 kg mol−1, but are permeable to proteins, such as lysozyme (14.3 kg mol−1) and cytochrome c (12.4 kg mol−1), due to the right balance of hydrogen bond interactions along the channels, electrostatic attraction, as well as the right pore sizes. Our results demonstrate that artificial channels can be designed for protein transport via block copolymer self-assembly using classical methods of membrane preparation.

  4. Making accessibility analyses accessible: A tool to facilitate the public review of the effects of regional transportation plans on accessibility

    OpenAIRE

    Golub, Aaron; Robinson, Glenn; Brendan Nee, Brendan Nee

    2013-01-01

    The regional transportation planning process in the United States has not been easily opened to public oversight even after strengthened requirements for public participation and civil rights considerations. In the effort to improve the public review of regional transportation plans, this paper describes the construction of a proof-of concept web-based tool designed to analyze the effects of regional transportation plans on accessibility to jobs and other essential destinations. The tool allo...

  5. Calculation of Selected Emissions from Transport Services in Road Public Transport

    Directory of Open Access Journals (Sweden)

    Konečný Vladimír

    2017-01-01

    Full Text Available The article deals with road public transport and its impact on the environment. According to the methodology given in EN 16258, CO2 emission value has been calculated. The input data for the calculation and the results are shown in the tables. The declaration is created according to STN CEN / TR 14310, which contains recommendations for compiling environmental reports. Finally, the comparison of the environmental impact of a bus and a passenger car, when converted to one passenger, bus has a lower CO2 emission than a passenger car in that section.

  6. Stochastic Pricing and Order Model with Transportation Mode Selection for Low-Carbon Retailers

    OpenAIRE

    Yi Zheng; Huchang Liao; Xue Yang

    2016-01-01

    More and more enterprises have begun to pay attention to their carbon footprint in the supply chain, of which transportation has become the second major source of carbon emissions. This paper aims to study both optimum pricing and order quantities, considering consumer demand and the selection of transportation modes by retailers, in terms of carbon emissions sensitivity and price sensitivity under the conditions of a cap-and-trade policy and uncertain market demand. Firstly, we analyze the e...

  7. Mathematical description of adsorption and transport of reactive solutes in soil: a review of selected literature

    International Nuclear Information System (INIS)

    Travis, C.C.

    1978-10-01

    This report reviews selected literature related to the mathematical description of the transport of reactive solutes through soil. The primary areas of the literature reviewed are (1) mathematical models in current use for description of the adsorption-desorption interaction between the soil solution and the soil matrix and (2) analytic solutions of the differential equations describing the convective-dispersive transport of reactive solutes through soil

  8. A metal-ion NMR investigation of the antibiotic facilitated transport of monovalent cations through the walls of phospholipid vesicles. II. Sulfur-33 NMR

    International Nuclear Information System (INIS)

    Buster, D.C.

    1988-01-01

    A technique has been developed to investigate the antibiotic facilitated transmembrane transport of monovalent cations using 23 Na and 7 Li Nuclear Magnetic Resonance spectroscopy. The initial portion of this thesis outlines the production and characterization of a model lipid system amenable to the NMR detection of cation transport. Large unilamellar vesicles (LUV) have been prepared from a 4:1 mixture of phosphatidylcholine and phosphatidylglycerol. The presence of the anionic chemical shift reagent dysprosium (III) tripolyphosphate, either inside or outside of the vesicles, allows for the spectroscopic separation of the NMR resonances arising from the inter- and extravesicular cation pools. The cation transporting properties of the channel-forming pentadecapeptide, gramicidin D, have been studied using the NMR technique

  9. Active colloids as mobile microelectrodes for unified label-free selective cargo transport.

    Science.gov (United States)

    Boymelgreen, Alicia M; Balli, Tov; Miloh, Touvia; Yossifon, Gilad

    2018-02-22

    Utilization of active colloids to transport both biological and inorganic cargo has been widely examined in the context of applications ranging from targeted drug delivery to sample analysis. In general, carriers are customized to load one specific target via a mechanism distinct from that driving the transport. Here we unify these tasks and extend loading capabilities to include on-demand selection of multiple nano/micro-sized targets without the need for pre-labelling or surface functionalization. An externally applied electric field is singularly used to drive the active cargo carrier and transform it into a mobile floating electrode that can attract (trap) or repel specific targets from its surface by dielectrophoresis, enabling dynamic control of target selection, loading and rate of transport via the electric field parameters. In the future, dynamic selectivity could be combined with directed motion to develop building blocks for bottom-up fabrication in applications such as additive manufacturing and soft robotics.

  10. On Transport Service Selection in Intermodal Rail/Road Distribution Networks

    Directory of Open Access Journals (Sweden)

    Christian Bierwirth

    2012-11-01

    Full Text Available Intermodal rail/road freight transport constitutes an alternative to long-haul road transport for the distribution of large volumes of goods. The paper introduces the intermodal transportation problem for the tactical planning of mode and service selection. In rail mode, shippers either book train capacity on a per-unit basis or charter block trains completely. Road mode is used for short-distance haulage to intermodal terminals and for direct shipments to customers. We analyze the competition of road and intermodal transportation with regard to freight consolidation and service cost on a model basis. The approach is applied to a distribution system of an industrial company serving customers in eastern Europe. The case study investigates the impact of transport cost and consolidation on the optimal modal split.

  11. Evaluation of selected predictive models and parameters for the environmental transport and dosimetry of radionuclides

    International Nuclear Information System (INIS)

    Miller, C.W.; Dunning, D.E. Jr.; Etnier, E.L.; Hoffman, F.O.; Little, C.A.; Meyer, H.R.; Shaeffer, D.L.; Till, J.E.

    1979-07-01

    Evaluations of selected predictive models and parameters used in the assessment of the environmental transport and dosimetry of radionuclides are summarized. Mator sections of this report include a validation of the Gaussian plume disperson model, comparison of the output of a model for the transport of 131 I from vegetation to milk with field data, validation of a model for the fraction of aerosols intercepted by vegetation, an evaluation of dose conversion factors for 232 Th, an evaluation of considering the effect of age dependency on population dose estimates, and a summary of validation results for hydrologic transport models

  12. Selective transport of Fe(III) using ionic imprinted polymer (IIP) membrane particle

    Science.gov (United States)

    Djunaidi, Muhammad Cholid; Jumina, Siswanta, Dwi; Ulbricht, Mathias

    2015-12-01

    The membrane particles was prepared from polyvinyl alcohol (PVA) and polymer IIP with weight ratios of 1: 2 and 1: 1 using different adsorbent templates and casting thickness. The permeability of membrane towards Fe(III) and also mecanism of transport were studied. The selectivity of the membrane for Fe(III) was studied by performing adsorption experiments also with Cr(III) separately. In this study, the preparation of Ionic Imprinted Polymer (IIP) membrane particles for selective transport of Fe (III) had been done using polyeugenol as functional polymer. Polyeugenol was then imprinted with Fe (III) and then crosslinked with PEGDE under alkaline condition to produce polyeugenol-Fe-PEGDE polymer aggregates. The agrregates was then crushed and sieved using mesh size of 80 and the powder was then used to prepare the membrane particles by mixing it with PVA (Mr 125,000) solution in 1-Methyl-2-pyrrolidone (NMP) solvent. The membrane was obtained after casting at a speed of 25 m/s and soaking in NaOH solution overnight. The membrane sheet was then cut and Fe(III) was removed by acid to produce IIP membrane particles. Analysis of the membrane and its constituent was done by XRD, SEM and size selectivity test. Experimental results showed the transport of Fe(III) was faster with the decrease of membrane thickness, while the higher concentration of template ion correlates with higher Fe(III) being transported. However, the transport of Fe(III) was slower for higher concentration of PVA in the membrane. IImparticles works through retarded permeation mechanism, where Fe(III) was bind to the active side of IIP. The active side of IIP membrane was dominated by the -OH groups. The selectivity of all IIP membranes was confirmed as they were all unable to transport Cr (III), while NIP (Non-imprinted Polymer) membrane was able transport Cr (III).

  13. M4FT-16LL080303052-State of Knowledge for Colloid Facilitated Radionuclide Transport and Update on Actinide Diffusion in Bentonite Backfill

    Energy Technology Data Exchange (ETDEWEB)

    Zavarin, Mavrik [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Glenn T. Seaborg Inst.. Physical and Life Sciences; Joseph, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Glenn T. Seaborg Inst.. Physical and Life Sciences

    2016-08-16

    This progress report (Level 4 Milestone Number M4FT-16LL080303052) summarizes research conducted at Lawrence Livermore National Laboratory (LLNL) within the Crystalline Disposal R&D Activity Number FT-16LL080303051 and Crystalline International Collaborations Activity Number FT-16LL080303061. The focus of this research is the interaction of radionuclides with Engineered Barrier System (EBS) and host rock materials at various physico-chemical conditions relevant to subsurface repository environments. They include both chemical and physical processes such as solubility, sorption, and diffusion. The colloid-facilitated transport effort focused on preparation of a draft manuscript summarizing the state of knowledge and parameterization of colloid-facilitated transport mechanisms in support of reactive transport and performance assessment models for generic crystalline repositories. This draft manuscript is being submitted as a level 3 milestone with LANL as the primary author. LLNL’s contribution to that effort is summarized only briefly in the present report. A manuscript summarizing long-term U(VI) diffusion experiments through bentonite backfill material was recently accepted for publication; the contents of that manuscript are summarized in the present report. The Np(IV) diffusion experiments were started mid-year and are ongoing. The completion of these experiments is planned for early FY17. Our progress in quantifying Np(IV) diffusion in bentonite backfill is summarized in the present report. Our involvement with the NEA TDB project was summarized in a recent Argillite Disposal activity report. It is not included in this report.

  14. Humic acid facilitates the transport of ARS-labeled hydroxyapatite nanoparticles in iron oxyhydroxide-coated sand

    Science.gov (United States)

    Hydroxyapatite nanoparticles (nHAP) have been widely used to remediate soil and wastewater contaminated with metals and radionuclides. However, our understanding of nHAP transport and fate is limited in natural environments that exhibit significant variability in solid and solution chemistry. The tr...

  15. Stochastic Pricing and Order Model with Transportation Mode Selection for Low-Carbon Retailers

    Directory of Open Access Journals (Sweden)

    Yi Zheng

    2016-01-01

    Full Text Available More and more enterprises have begun to pay attention to their carbon footprint in the supply chain, of which transportation has become the second major source of carbon emissions. This paper aims to study both optimum pricing and order quantities, considering consumer demand and the selection of transportation modes by retailers, in terms of carbon emissions sensitivity and price sensitivity under the conditions of a cap-and-trade policy and uncertain market demand. Firstly, we analyze the effects of transportation mode (including transportation costs and transportation-induced carbon emissions, initial emissions allowances, carbon emissions trading price and consumer sensitivity to carbon emissions on the optimum decisions and profits of retailers. The results demonstrate that when consumers are less sensitive to price, the optimum retail price and the optimum order quantity of products are proportional to the transportation cost and transportation-induced carbon emissions of retailers per unit product, the carbon emissions trading price as well as consumer sensitivity to carbon emissions. However, when consumers are highly sensitive to price, the optimum order quantity of products is inversely proportional to the transportation costs and transportation-induced carbon emissions of retailers per unit product, the carbon emissions trading price and consumer sensitivity to carbon emissions. In addition, the optimum retail price of products is inversely proportional to consumer sensitivity to carbon emissions. We also find that retailers prefer a low-carbon transportation mode when the carbon emissions trading price is high. Meanwhile, the carbon emissions trading price influences the carbon emissions trading volume of retailers. These theoretical findings are further validated by some numerical analysis.

  16. Safety Standard for Oxygen and Oxygen Systems: Guidelines for Oxygen System Design, Materials Selection, Operations, Storage, and Transportation

    Science.gov (United States)

    1996-01-01

    NASA's standard for oxygen system design, materials selection, operation, and transportation is presented. Minimum guidelines applicable to NASA Headquarters and all NASA Field Installations are contained.

  17. Humic acid facilitates the transport of ARS-labeled hydroxyapatite nanoparticles in iron oxyhydroxide-coated sand

    Science.gov (United States)

    Wang, Dengjun; Bradford, Scott A.; Harvey, Ronald W.; Gao, Bin; Cang, Long; Zhou, Dongmei

    2012-01-01

    Hydroxyapatite nanoparticles (nHAP) have been widely used to remediate soil and wastewater contaminated with metals and radionuclides. However, our understanding of nHAP transport and fate is limited in natural environments that exhibit significant variability in solid and solution chemistry. The transport and retention kinetics of Alizarin red S (ARS)-labeled nHAP were investigated in water-saturated packed columns that encompassed a range of humic acid concentrations (HA, 0–10 mg L–1), fractional surface coverage of iron oxyhydroxide coatings on sand grains (λ, 0–0.75), and pH (6.0–10.5). HA was found to have a marked effect on the electrokinetic properties of ARS-nHAP, and on the transport and retention of ARS-nHAP in granular media. The transport of ARS-nHAP was found to increase with increasing HA concentration because of enhanced colloidal stability and the reduced aggregate size. When HA = 10 mg L–1, greater ARS-nHAP attachment occurred with increasing λ because of increased electrostatic attraction between negatively charged nanoparticles and positively charged iron oxyhydroxides, although alkaline conditions (pH 8.0 and 10.5) reversed the surface charge of the iron oxyhydroxides and therefore decreased deposition. The retention profiles of ARS-nHAP exhibited a hyperexponential shape for all test conditions, suggesting some unfavorable attachment conditions. Retarded breakthrough curves occurred in sands with iron oxyhydroxide coatings because of time-dependent occupation of favorable deposition sites. Consideration of the above effects is necessary to improve remediation efficiency of nHAP for metals and actinides in soils and subsurface environments.

  18. Identification of a Stelar-Localized Transport Protein That Facilitates Root-to-Shoot Transfer of Chloride in Arabidopsis

    KAUST Repository

    Li, Bo

    2015-12-11

    Under saline conditions, higher plants restrict the accumulation of chloride ions (Cl–) in the shoot by regulating their transfer from the root symplast into the xylem-associated apoplast. To identify molecular mechanisms underpinning this phenomenon, we undertook a transcriptional screen of salt stressed Arabidopsis (Arabidopsis thaliana) roots. Microarrays, quantitative RT-PCR, and promoter-GUS fusions identified a candidate gene involved in Cl– xylem loading from the Nitrate transporter 1/Peptide Transporter family (NPF2.4). This gene was highly expressed in the root stele compared to the cortex, and its expression decreased after exposure to NaCl or abscisic acid. NPF2.4 fused to fluorescent proteins, expressed either transiently or stably, was targeted to the plasma membrane. Electrophysiological analysis of NPF2.4 in Xenopus laevis oocytes suggested that NPF2.4 catalyzed passive Cl– efflux out of cells and was much less permeable to NO3−. Shoot Cl– accumulation was decreased following NPF2.4 artificial microRNA knockdown, whereas it was increased by overexpression of NPF2.4. Taken together, these results suggest that NPF2.4 is involved in long-distance transport of Cl– in plants, playing a role in the loading and the regulation of Cl– loading into the xylem of Arabidopsis roots during salinity stress.

  19. Identification of a Stelar-Localized Transport Protein That Facilitates Root-to-Shoot Transfer of Chloride in Arabidopsis

    KAUST Repository

    Li, Bo; Byrt, Caitlin; Qiu, Jiaen; Baumann, Ute; Hrmova, Maria; Evrard, Aurelie; Johnson, Alexander A T; Birnbaum, Kenneth D.; Mayo, Gwenda M.; Jha, Deepa; Henderson, Sam W.; Tester, Mark A.; Gilliham, Mathew; Roy, Stuart J.

    2015-01-01

    Under saline conditions, higher plants restrict the accumulation of chloride ions (Cl–) in the shoot by regulating their transfer from the root symplast into the xylem-associated apoplast. To identify molecular mechanisms underpinning this phenomenon, we undertook a transcriptional screen of salt stressed Arabidopsis (Arabidopsis thaliana) roots. Microarrays, quantitative RT-PCR, and promoter-GUS fusions identified a candidate gene involved in Cl– xylem loading from the Nitrate transporter 1/Peptide Transporter family (NPF2.4). This gene was highly expressed in the root stele compared to the cortex, and its expression decreased after exposure to NaCl or abscisic acid. NPF2.4 fused to fluorescent proteins, expressed either transiently or stably, was targeted to the plasma membrane. Electrophysiological analysis of NPF2.4 in Xenopus laevis oocytes suggested that NPF2.4 catalyzed passive Cl– efflux out of cells and was much less permeable to NO3−. Shoot Cl– accumulation was decreased following NPF2.4 artificial microRNA knockdown, whereas it was increased by overexpression of NPF2.4. Taken together, these results suggest that NPF2.4 is involved in long-distance transport of Cl– in plants, playing a role in the loading and the regulation of Cl– loading into the xylem of Arabidopsis roots during salinity stress.

  20. Resonance induced spin-selective transport behavior in carbon nanoribbon/nanotube/nanoribbon heterojunctions

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiang-Hua [School of Physics and Microelectronics Science, Hunan University, Changsha 410082 (China); Department of Electrical and Information Engineering, Hunan Institute of Engineering, Xiangtan 411101 (China); Wang, Ling-Ling, E-mail: llwang@hnu.edu.cn [School of Physics and Microelectronics Science, Hunan University, Changsha 410082 (China); Li, Xiao-Fei, E-mail: xf.li@uestc.edu.cn [School of Physics and Microelectronics Science, Hunan University, Changsha 410082 (China); School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054 (China); Chen, Tong; Li, Quan [School of Physics and Microelectronics Science, Hunan University, Changsha 410082 (China)

    2015-09-04

    Carbon nanotubes (CNTs) and graphene nanoribbons (GNRs) are attractive in spintronics. Here, we propose GNR/CNT/GNR heterojunctions constructed by attaching zigzag-GNRs at the side-wall of CNT for spintronic devices. The thermal stability and electronic transport properties were explored using ab initio molecular dynamics simulations and nonequilibrium Green's function methods, respectively. Results demonstrate that the sp{sup 3}-hybridized contacts formed at the interface assure a good thermal stability of the system and make the CNT to be regarded as resonator. Only the electron of one spin-orientation and resonant energy is allowed to transport, resulting in the remarkable spin-selective transport behavior at the ferromagnetic state. - Highlights: • The new mechanism for spin-selective transport in molecular junction is proposed. • The two sp{sup 3} contacts formed between CNT and GNR can be regarded as electronic isolators. • The two isolators make the CNT act as a resonator. • Only the electron of one spin-orientation and resonant energy can form standing wave and transport through the whole junction.

  1. Outsourcing strategy selection for transportation services based on the Make or Buy decision

    Directory of Open Access Journals (Sweden)

    Maria CIEŚLA

    2015-06-01

    Full Text Available This paper is related to the practical approach to logistics strategies in enterprises and advanced practical applications. This article presents an analysis and solution to a specific problem, which is the subject of transport in the enterprise. It presents an analysis based on Make-or-Buy decision involving the selection of best internal or external transport service. It will be used for an exemplary production company. This case study presents the basis for the construction of logistics strategy of the company as a competitive advantage in the market.

  2. The blood-brain barrier fatty acid transport protein 1 (FATP1/SLC27A1) supplies docosahexaenoic acid to the brain, and insulin facilitates transport.

    Science.gov (United States)

    Ochiai, Yusuke; Uchida, Yasuo; Ohtsuki, Sumio; Tachikawa, Masanori; Aizawa, Sanshiro; Terasaki, Tetsuya

    2017-05-01

    We purposed to clarify the contribution of fatty acid transport protein 1 (FATP1/SLC 27A1) to the supply of docosahexaenoic acid (DHA) to the brain across the blood-brain barrier in this study. Transport experiments showed that the uptake rate of [ 14 C]-DHA in human FATP1-expressing HEK293 cells was significantly greater than that in empty vector-transfected (mock) HEK293 cells. The steady-state intracellular DHA concentration was nearly 2-fold smaller in FATP1-expressing than in mock cells, suggesting that FATP1 works as not only an influx, but also an efflux transporter for DHA. [ 14 C]-DHA uptake by a human cerebral microvascular endothelial cell line (hCMEC/D3) increased in a time-dependent manner, and was inhibited by unlabeled DHA and a known FATP1 substrate, oleic acid. Knock-down of FATP1 in hCMEC/D3 cells with specific siRNA showed that FATP1-mediated uptake accounts for 59.2-73.0% of total [ 14 C]-DHA uptake by the cells. Insulin treatment for 30 min induced translocation of FATP1 protein to the plasma membrane in hCMEC/D3 cells and enhanced [ 14 C]-DHA uptake. Immunohistochemical analysis of mouse brain sections showed that FATP1 protein is preferentially localized at the basal membrane of brain microvessel endothelial cells. We found that two neuroprotective substances, taurine and biotin, in addition to DHA, undergo FATP1-mediated efflux. Overall, our results suggest that FATP1 localized at the basal membrane of brain microvessels contributes to the transport of DHA, taurine and biotin into the brain, and insulin rapidly increases DHA supply to the brain by promoting translocation of FATP1 to the membrane. Read the Editorial Comment for this article on page 324. © 2016 International Society for Neurochemistry.

  3. Two zinc-binding domains in the transporter AdcA from Streptococcus pyogenes facilitate high-affinity binding and fast transport of zinc.

    Science.gov (United States)

    Cao, Kun; Li, Nan; Wang, Hongcui; Cao, Xin; He, Jiaojiao; Zhang, Bing; He, Qing-Yu; Zhang, Gong; Sun, Xuesong

    2018-04-20

    Zinc is an essential metal in bacteria. One important bacterial zinc transporter is AdcA, and most bacteria possess AdcA homologs that are single-domain small proteins due to better efficiency of protein biogenesis. However, a double-domain AdcA with two zinc-binding sites is significantly overrepresented in Streptococcus species, many of which are major human pathogens. Using molecular simulation and experimental validations of AdcA from Streptococcus pyogenes , we found here that the two AdcA domains sequentially stabilize the structure upon zinc binding, indicating an organization required for both increased zinc affinity and transfer speed. This structural organization appears to endow Streptococcus species with distinct advantages in zinc-depleted environments, which would not be achieved by each single AdcA domain alone. This enhanced zinc transport mechanism sheds light on the significance of the evolution of the AdcA domain fusion, provides new insights into double-domain transporter proteins with two binding sites for the same ion, and indicates a potential target of antimicrobial drugs against pathogenic Streptococcus species. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. TFG facilitates outer coat disassembly on COPII transport carriers to promote tethering and fusion with ER-Golgi intermediate compartments.

    Science.gov (United States)

    Hanna, Michael G; Block, Samuel; Frankel, E B; Hou, Feng; Johnson, Adam; Yuan, Lin; Knight, Gavin; Moresco, James J; Yates, John R; Ashton, Randolph; Schekman, Randy; Tong, Yufeng; Audhya, Anjon

    2017-09-12

    The conserved coat protein complex II (COPII) mediates the initial steps of secretory protein trafficking by assembling onto subdomains of the endoplasmic reticulum (ER) in two layers to generate cargo-laden transport carriers that ultimately fuse with an adjacent ER-Golgi intermediate compartment (ERGIC). Here, we demonstrate that Trk-fused gene (TFG) binds directly to the inner layer of the COPII coat. Specifically, the TFG C terminus interacts with Sec23 through a shared interface with the outer COPII coat and the cargo receptor Tango1/cTAGE5. Our findings indicate that TFG binding to Sec23 outcompetes these other associations in a concentration-dependent manner and ultimately promotes outer coat dissociation. Additionally, we demonstrate that TFG tethers vesicles harboring the inner COPII coat, which contributes to their clustering between the ER and ERGIC in cells. Together, our studies define a mechanism by which COPII transport carriers are retained locally at the ER/ERGIC interface after outer coat disassembly, which is a prerequisite for fusion with ERGIC membranes.

  5. Monocarboxylate transporter 4 facilitates cell proliferation and migration and is associated with poor prognosis in oral squamous cell carcinoma patients.

    Directory of Open Access Journals (Sweden)

    Jiang Zhu

    Full Text Available Monocarboxylate transporter 4 (MCT4 is a cell membrane transporter of lactate. Recent studies have shown that MCT4 is over-expressed in various cancers; however, its role in cancer maintenance and aggressiveness has not been fully demonstrated. This study investigated the role of MCT4 in oral squamous cell carcinoma (OSCC, and found that it is highly expressed in OSCC patients by using immunohistochemistry. Moreover, this over-expression of MCT4 was closely associated with tumor size, TNM classification, lymphatic metastasis, distant metastasis and tumor recurrence, and also poor prognosis. To further study mechanisms of MCT4 in vitro, we used small-interfering RNA to silence its expression in OSCC cell lines. The results showed that knock-down of MCT4 decreased cell proliferation, migration, and invasion. The inhibition of proliferation was associated with down-regulation of p-AKT and p-ERK1/2, while decreased cell migration and invasion may be caused by down-regulation of integrin β4-SRC-FAK and MEK-ERK signaling. Together, these findings provide new insight into the critical role of MCT4 in cell proliferation and metastasis in OSCC.

  6. Automating Risk Assessments of Hazardous Material Shipments for Transportation Routes and Mode Selection

    International Nuclear Information System (INIS)

    Dolphin, Barbara H.; Richins, William D.; Novascone, Stephen R.

    2010-01-01

    The METEOR project at Idaho National Laboratory (INL) successfully addresses the difficult problem in risk assessment analyses of combining the results from bounding deterministic simulation results with probabilistic (Monte Carlo) risk assessment techniques. This paper describes a software suite designed to perform sensitivity and cost/benefit analyses on selected transportation routes and vehicles to minimize risk associated with the shipment of hazardous materials. METEOR uses Monte Carlo techniques to estimate the probability of an accidental release of a hazardous substance along a proposed transportation route. A METEOR user selects the mode of transportation, origin and destination points, and charts the route using interactive graphics. Inputs to METEOR (many selections built in) include crash rates for the specific aircraft, soil/rock type and population densities over the proposed route, and bounding limits for potential accident types (velocity, temperature, etc.). New vehicle, materials, and location data are added when available. If the risk estimates are unacceptable, the risks associated with alternate transportation modes or routes can be quickly evaluated and compared. Systematic optimizing methods will provide the user with the route and vehicle selection identified with the lowest risk of hazardous material release. The effects of a selected range of potential accidents such as vehicle impact, fire, fuel explosions, excessive containment pressure, flooding, etc. are evaluated primarily using hydrocodes capable of accurately simulating the material response of critical containment components. Bounding conditions that represent credible accidents (i.e; for an impact event, velocity, orientations, and soil conditions) are used as input parameters to the hydrocode models yielding correlation functions relating accident parameters to component damage. The Monte Carlo algorithms use random number generators to make selections at the various decision

  7. Development of selected advanced aerodynamics and active control concepts for commercial transport aircraft

    Science.gov (United States)

    Taylor, A. B.

    1984-01-01

    Work done under the Energy Efficient Transport project in the field of advanced aerodynamics and active controls is summarized. The project task selections focused on the following: the investigation of long-duct nacelle shape variation on interference drag; the investigation of the adequacy of a simple control law for the elastic modes of a wing; the development of the aerodynamic technology at cruise and low speed of high-aspect-ratio supercritical wings of high performance; and the development of winglets for a second-generation jet transport. All the tasks involved analysis and substantial wind tunnel testing. The winglet program also included flight evaluation. It is considered that the technology base has been built for the application of high-aspect-ratio supercritical wings and for the use of winglets on second-generation transports.

  8. Behavioral performance follows the time course of neural facilitation and suppression during cued shifts of feature-selective attention

    OpenAIRE

    Andersen, S. K.; Müller, M. M.

    2010-01-01

    A central question in the field of attention is whether visual processing is a strictly limited resource, which must be allocated by selective attention. If this were the case, attentional enhancement of one stimulus should invariably lead to suppression of unattended distracter stimuli. Here we examine voluntary cued shifts of feature-selective attention to either one of two superimposed red or blue random dot kinematograms (RDKs) to test whether such a reciprocal relationship between enhanc...

  9. FGT-1 is a mammalian GLUT2-like facilitative glucose transporter in Caenorhabditis elegans whose malfunction induces fat accumulation in intestinal cells.

    Directory of Open Access Journals (Sweden)

    Shun Kitaoka

    Full Text Available Caenorhabditis elegans (C. elegans is an attractive animal model for biological and biomedical research because it permits relatively easy genetic dissection of cellular pathways, including insulin/IGF-like signaling (IIS, that are conserved in mammalian cells. To explore C. elegans as a model system to study the regulation of the facilitative glucose transporter (GLUT, we have characterized the GLUT gene homologues in C. elegans: fgt-1, R09B5.11, C35A11.4, F53H8.3, F48E3.2, F13B12.2, Y61A9LA.1, K08F9.1 and Y37A1A.3. The exogenous expression of these gene products in Xenopus oocytes showed transport activity to unmetabolized glucose analogue 2-deoxy-D-glucose only in FGT-1. The FGT-1-mediated transport activity was inhibited by the specific GLUT inhibitor phloretin and exhibited a Michaelis constant (Km of 2.8 mM. Mannose, galactose, and fructose were able to inhibit FGT-1-mediated 2-deoxy-D-glucose uptake (P < 0.01, indicating that FGT-1 is also able to transport these hexose sugars. A GFP fusion protein of FGT-1 was observed only on the basolateral membrane of digestive tract epithelia in C. elegans, but not in other tissues. FGT-1::eGFP expression was observed from early embryonic stages. The knockdown or mutation of fgt-1 resulted in increased fat staining in both wild-type and daf-2 (mammalian insulin receptor homologue mutant animals. Other common phenotypes of IIS mutant animals, including dauer formation and brood size reduction, were not affected by fgt-1 knockdown in wild-type or daf-2 mutants. Our results indicated that in C. elegans, FGT-1 is mainly a mammalian GLUT2-like intestinal glucose transporter and is involved in lipid metabolism.

  10. Monsoon-facilitated characteristics and transport of atmospheric mercury at a high-altitude background site in southwestern China

    Directory of Open Access Journals (Sweden)

    H. Zhang

    2016-10-01

    Full Text Available To better understand the influence of monsoonal climate and transport of atmospheric mercury (Hg in southwestern China, measurements of total gaseous mercury (TGM, defined as the sum of gaseous elemental mercury, GEM, and gaseous oxidized mercury, GOM, particulate bound mercury (PBM and GOM were carried out at Ailaoshan Station (ALS, 2450 m a.s.l. in southwestern China from May 2011 to May 2012. The mean concentrations (± SD for TGM, GOM and PBM were 2.09 ± 0.63, 2.2 ± 2.3 and 31.3 ± 28.4 pg m−3, respectively. TGM showed a monsoonal distribution pattern with relatively higher concentrations (2.22 ± 0.58 ng m−3, p  =  0.021 during the Indian summer monsoon (ISM, from May to September and the east Asia summer monsoon (EASM, from May to September periods than that (1.99 ± 0.66 ng m−3 in the non-ISM period. Similarly, GOM and PBM concentrations were higher during the ISM period than during the non-ISM period. This study suggests that the ISM and the EASM have a strong impact on long-range and transboundary transport of Hg between southwestern China and south and southeast Asia. Several high TGM events were accompanied by the occurrence of northern wind during the ISM period, indicating anthropogenic Hg emissions from inland China could rapidly increase TGM levels at ALS due to strengthening of the EASM. Most of the TGM and PBM events occurred at ALS during the non-ISM period. Meanwhile, high CO concentrations were also observed at ALS, indicating that a strong south tributary of westerlies could have transported Hg from south and southeast Asia to southwestern China during the non-ISM period. The biomass burning in southeast Asia and anthropogenic Hg emissions from south Asia are thought to be the source of atmospheric Hg in remote areas of southwestern China during the non-ISM period.

  11. Modified random hinge transport mechanics and multiple scattering step-size selection in EGS5

    International Nuclear Information System (INIS)

    Wilderman, S.J.; Bielajew, A.F.

    2005-01-01

    The new transport mechanics in EGS5 allows for significantly longer electron transport step sizes and hence shorter computation times than required for identical problems in EGS4. But as with all Monte Carlo electron transport algorithms, certain classes of problems exhibit step-size dependencies even when operating within recommended ranges, sometimes making selection of step-sizes a daunting task for novice users. Further contributing to this problem, because of the decoupling of multiple scattering and continuous energy loss in the dual random hinge transport mechanics of EGS5, there are two independent step sizes in EGS5, one for multiple scattering and one for continuous energy loss, each of which influences speed and accuracy in a different manner. Further, whereas EGS4 used a single value of fractional energy loss (ESTEPE) to determine step sizes at all energies, to increase performance by decreasing the amount of effort expended simulating lower energy particles, EGS5 permits the fractional energy loss values which are used to determine both the multiple scattering and continuous energy loss step sizes to vary with energy. This results in requiring the user to specify four fractional energy loss values when optimizing computations for speed. Thus, in order to simplify step-size selection and to mitigate step-size dependencies, a method has been devised to automatically optimize step-size selection based on a single material dependent input related to the size of problem tally region. In this paper we discuss the new transport mechanics in EGS5 and describe the automatic step-size optimization algorithm. (author)

  12. Investigating selective transport and abrasion on an alluvial fan using quantitative grain size and shape analysis

    Science.gov (United States)

    Litwin, K. L.; Jerolmack, D. J.

    2011-12-01

    Selective sorting and abrasion are the two major fluvial processes that are attributed to the downstream fining of sediments in rivers and alluvial fans. Selective transport is the process by which smaller grains are preferentially transported downstream while larger grains are deposited closer to the source. Abrasion is defined by the production of fine sediments and sand that occurs by saltation of gravel, where particle-to-particle collisions supply the energy required to break apart grains. We hypothesize that abrasion results in the gradual fining of large grains and the production of fine sands and silts, while sorting accounts for the differences in transport of these two grain-size fractions produced from abrasion, thereby creating the abrupt gravel-sand transition observed in many channel systems. In this research, we explore both selective transport and abrasion processes on the Dog Canyon alluvial fan near Alamogordo, New Mexico. We complete an extensive grain size analysis down the main channel of the fan employing an image-based technique that utilizes an autocorrelation process. We also characterize changes in grain shape using standard shape parameters, as well as Fourier analysis, which allows the study of contributions of grain roughness on a variety of length scales. Sorting appears to dominate the upper portion of the fan; the grain-size distribution narrows moving downstream until reaching a point of equal mobility, at which point sorting ceases. Abrasion exerts a subtle but persistent effect on grains during transport down the fan. Shape analysis reveals that particles become more rounded by the removal of small-scale textural features, a process that is expected to only modestly influence grain size of gravel, but should produce significant quantities of sand. This study provides a better understanding of the importance of grain abrasion and sorting on the downstream fining of channel grains in an alluvial fan, as well as an improved knowledge

  13. Mechanism of molecular transport in novel reverse-selective nanocomposite membranes

    International Nuclear Information System (INIS)

    Merkel, T.C.; Freeman, B.D.; Spontak, R.J.; Meakin, P.; Hill, A.J.; Monash University, VIC

    2002-01-01

    Full text: Polymer nanocomposites continue to receive tremendous attention as organic-inorganic hybrid materials exhibiting a wide range of interesting, as well as technologically relevant, properties. This work reports a novel use of polymer nanocomposites as reverse-selective membranes. We have found that physical dispersion of nonporous fumed silica [FS] into glassy poly(4-methyl-2-pentyne) [PMP] simultaneously enhances membrane permeability (by as much as 240%) and selectivity for large organic molecules over small permanent gases. This surprising observation, in stark contrast to conventional filled polymer systems, reflects silica-induced disruption of local polymer chain packing and, as discerned by positron annihilation lifetime spectroscopy [PALS], a resulting subtle increase in the size of free volume elements through which molecular transport occurs. Such nanoscale hybridization represents an innovative means of tuning the transport properties of glassy polymeric media through control of molecular ordering

  14. Selective transport of metal ions through cation exchange membrane in the presence of a complexing agent

    Energy Technology Data Exchange (ETDEWEB)

    Tingchia Huang; Jaukai Wang (National Cheng Kung Univ., Tainan (Taiwan, Province of China))

    1993-01-01

    Selective transport of metal ions through a cation exchange membrane was studied in stirred batch dialyzer for the systems Ni[sup 2+]-Cu[sup 2+] and Cu[sup 2+]-Fe[sup 3+]. Oxalic acid, malonic acid, citric acid, glycine, and ethylenediaminetetraacetic acid were employed as the complexing agents added in the feed solution in order to increase the permselectivity of metal ions. The experimental results show that the selective transport behavior of metal ions depends on the valence and the concentration of metal ions, the stoichiometric ratio of complexing agent to metal ions, and the pH value of the feed solution, but is independent of the concentration of counterion in the stripping phase. A theoretical approach was formulated on the basis of the Nernst-Planck equation and interface quasi-equilibrium. Theoretical solutions obtained from numerical calculation were in agreement with the experimental data.

  15. Plasma turbulence. Structure formation, selection rule, dynamic response and dynamics transport

    International Nuclear Information System (INIS)

    Ito, Sanae I.

    2010-01-01

    The five-year project of Grant-in-Aid for Specially Promoted Research entitled general research on the structure formation and selection rule in plasma turbulence had brought many outcomes. Based on these outcomes, the Grant-in-Aid for Scientific Research (S) program entitled general research on dynamic response and dynamic transport in plasma turbulence has started. In the present paper, the state-of-the-art of the research activities on the structure formation, selection rule and dynamics in plasma turbulence are reviewed with reference to outcomes of these projects. (author)

  16. Discovery of the first selective inhibitor of excitatory amino acid transporter subtype 1

    DEFF Research Database (Denmark)

    Jensen, Anders Asbjørn; Erichsen, Mette Navy; Nielsen, Christina Wøhlk

    2009-01-01

    The discovery of the first class of subtype-selective inhibitors of the human excitatory amino acid transporter subtype 1 (EAAT1) and its rat orthologue GLAST is reported. An opening structure-activity relationship of 25 analogues is presented that addresses the influence of substitutions at the 4......- and 7-positions of the parental skeleton 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile. The most potent analogue 1o displays high nanomolar inhibitory activity at EAAT1 and a >400-fold selectivity over EAAT2 and EAAT3, making it a highly valuable pharmacological tool....

  17. Selective segmental sclerotherapy of the liver by transportal absolute ethanol injection: an animal experimental study

    International Nuclear Information System (INIS)

    Pan Jie; Yang Ning; Zhang Zhongzhong; Hu Libin; Chen Jie; Wu Wei; Jin Zhengyu; Liu Wei

    2003-01-01

    Objective: To evaluate the safety and efficacy of selective segmental sclerotherapy (SSS) of the liver by transportal absolute ethanol injection with an animal experimental study, and to discuss several technical points involved in this method. Methods: Thirty dogs received SSS of the liver by transportal absolute ethanol injection with the injection dose of 0.2-1.0 ml/kg, repeated examinations of blood ethanol level, WBC, and liver functions were done, and CT and pathological examinations of the liver were performed. Results: All dogs treated with SSS survived during the study. The maximum elevation of blood ethanol values occurred in group F. Its average value was (1.603 ± 0.083) mg/ml, which was much lower than that of death level. Transient elevations of blood WBC and ALT were seen. The average values of WBC and ALT were (46.36 ± 7.28) x 10 9 and (827.36 ± 147.25) U/L, respectively. CT and pathological examinations proved that the dogs given SSS by transportal absolute ethanol injection with the injection dose of 0.3-1.0 ml/kg had a complete wedge-shaped necrosis in the liver. Conclusion: Selective segmental sclerotherapy of the liver by transportal ethanol injection was quite safe and effective if the proper dose of ethanol was injected. SSS may be useful in the treatment of HCC

  18. Size-Selective Modes of Aeolian Transport on Earth and Mars

    Science.gov (United States)

    Swann, C.; Ewing, R. C.; Sherman, D. J.; McLean, C. J.

    2016-12-01

    Aeolian sand transport is a dominant driver of surface change and dust emission on Mars. Estimates of aeolian sand transport on Earth and Mars rely on terrestrial transport models that do not differentiate between transport modes (e.g., creep vs. saltation), which limits estimates of the critical threshold for transport and the total sand flux during a transport event. A gap remains in understanding how the different modes contribute to the total sand flux. Experiments conducted at the MARtian Surface WInd Tunnel separated modes of transport for uniform and mixed grain size surfaces at Earth and Martian atmospheric pressures. Crushed walnut shells with a density of 1.0 gm/cm3 were used. Experiments resolved grain size distributions for creeping and saltating grains over 3 uniform surfaces, U1, U2, and U3, with median grain sizes of 308 µm, 721 µm, and 1294 µm, and a mixed grain size surface, M1, with median grain sizes of 519 µm. A mesh trap located 5 cm above the test bed and a surface creep trap were deployed to capture particles moving as saltation and creep. Grains that entered the creep trap at angles ≥ 75° were categorized as moving in creep mode only. Only U1 and M1 surfaces captured enough surface creep at both Earth and Mars pressure for statistically significant grain size analysis. Our experiments show that size selective transport differs between Earth and Mars conditions. The median grain size of particles moving in creep for both uniform and mixed surfaces are larger under Earth conditions. (U1Earth = 385 µm vs. U1Mars = 355 µm; M1Earth = 762 vs. M1Mars = 697 µm ). However, particles moving in saltation were larger under Mars conditions (U1Earth = 282 µm; U1Mars = 309 µm; M1Earth = 347 µm; M1Mars = 454 µm ). Similar to terrestrial experiments, the median size of surface creep is larger than the median grain size of saltation. Median sizes of U1, U2, U3 at Mars conditions for creep was 355 µm, 774 µm and 1574 µm. Saltation at Mars

  19. Facilitated transport of Cr(III) through activated composite membrane containing di-(2-ethylhexyl)phosphoric acid (DEHPA) as carrier agent

    International Nuclear Information System (INIS)

    Arslan, Gulsin; Tor, Ali; Cengeloglu, Yunus; Ersoz, Mustafa

    2009-01-01

    The facilitated transport of chromium(III) through activated composite membrane (ACM) containing di-(2-ethylhexyl) phosphoric acid (DEHPA) was investigated. DEHPA was immobilised by interfacial polymerisation on polysulfone layer which was deposited on non-woven fabric by using spin coater. Then, ACM was characterised by using scanning electron microscopy (SEM), contact angle measurements and atomic force microscopy (AFM). Initially, batch experiments of liquid-liquid distribution of Cr(III) and the extractant (DEHPA) were carried out to determine the appropriate pH of the feed phase and the results showed that maximum extraction of Cr(III) was achieved at a pH of 4. It was also found that Cr(III) and DEHPA reacted in 1/1 molar ratio. The effects of Cr(III) (in feed phase), HCl (in stripping phase) and DEHPA (in ACM) concentrations were investigated. DEHPA concentration varies from 0.1 to 1.0 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.8 M. It was also observed that the transport of Cr(III) through the ACM tended to increase with Cr(III) and HCl concentrations. The stability of ACM was also confirmed with replicate experiments.

  20. Facilitated transport of Cr(III) through activated composite membrane containing di-(2-ethylhexyl)phosphoric acid (DEHPA) as carrier agent

    Energy Technology Data Exchange (ETDEWEB)

    Arslan, Gulsin [Department of Chemistry, Selcuk University, 42031, Campus, Konya (Turkey); Tor, Ali, E-mail: ator@selcuk.edu.tr [Department of Environmental Engineering, Selcuk University, 42031 Campus, Konya (Turkey); Cengeloglu, Yunus; Ersoz, Mustafa [Department of Chemistry, Selcuk University, 42031, Campus, Konya (Turkey)

    2009-06-15

    The facilitated transport of chromium(III) through activated composite membrane (ACM) containing di-(2-ethylhexyl) phosphoric acid (DEHPA) was investigated. DEHPA was immobilised by interfacial polymerisation on polysulfone layer which was deposited on non-woven fabric by using spin coater. Then, ACM was characterised by using scanning electron microscopy (SEM), contact angle measurements and atomic force microscopy (AFM). Initially, batch experiments of liquid-liquid distribution of Cr(III) and the extractant (DEHPA) were carried out to determine the appropriate pH of the feed phase and the results showed that maximum extraction of Cr(III) was achieved at a pH of 4. It was also found that Cr(III) and DEHPA reacted in 1/1 molar ratio. The effects of Cr(III) (in feed phase), HCl (in stripping phase) and DEHPA (in ACM) concentrations were investigated. DEHPA concentration varies from 0.1 to 1.0 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.8 M. It was also observed that the transport of Cr(III) through the ACM tended to increase with Cr(III) and HCl concentrations. The stability of ACM was also confirmed with replicate experiments.

  1. Selective pumping in a network: insect-style microscale flow transport

    International Nuclear Information System (INIS)

    Aboelkassem, Yasser; Staples, Anne E

    2013-01-01

    A new paradigm for selective pumping of fluids in a complex network of channels in the microscale flow regime is presented. The model is inspired by internal flow distributions produced by the rhythmic wall contractions observed in many insect tracheal networks. The approach presented here is a natural extension of previous two-dimensional modeling of insect-inspired microscale flow transport in a single channel, and aims to manipulate fluids efficiently in microscale networks without the use of any mechanical valves. This selective pumping approach enables fluids to be transported, controlled and precisely directed into a specific branch in a network while avoiding other possible routes. In order to present a quantitative analysis of the selective pumping approach presented here, the velocity and pressure fields and the time-averaged net flow that are induced by prescribed wall contractions are calculated numerically using the method of fundamental solutions. More specifically, the Stokeslets-meshfree method is used in this study to solve the Stokes equations that govern the flow motions in a network with moving wall contractions. The results presented here might help in understanding some features of the insect respiratory system function and guide efforts to fabricate novel microfluidic devices for flow transport and mixing, and targeted drug delivery applications. (paper)

  2. Separation of Binary Mixtures of Propylene and Propane by Facilitated Transport through Silver Incorporated Poly(Ether-Block-Amide Membranes

    Directory of Open Access Journals (Sweden)

    Surya Murali R.

    2015-02-01

    Full Text Available The separation of propylene and propane is a challenging task in petroleum refineries due to the similar molecular sizes and physical properties of two gases. Composite Poly(ether-block-amide (Pebax-1657 membranes incorporated with silver tetra fluoroborate (AgBF4 in concentrations of 0-50% of the polymer weight were prepared by solution casting and solvent evaporation technique. The membranes were characterized by Scanning Electron Microscopy (SEM, Fourier Transform InfraRed (FTIR and wide-angle X-ray Diffraction (XRD to study surface and cross-sectional morphologies, effect of incorporation on intermolecular interactions and degree of crystallinity, respectively. Experimental data was measured with an indigenously built high-pressure gas separation manifold having an effective membrane area of 42 cm2. Permeability and selectivity of membranes were determined for three different binary mixtures of propylene-propane at pressures varying in the range 2-6 bar. Selectivity of C3H6/C3H8 enhanced from 2.92 to 17.22 and 2.11 to 20.38 for 50/50 and 66/34 C3H6+C3H8 feed mixtures, respectively, with increasing loading of AgBF4. Pebax membranes incorporated with AgBF4 exhibit strong potential for the separation of C3H6/C3H8 mixtures in petroleum refineries.

  3. HEURISTIC METHOD OF SHIPS SELECTION FOR THE COORDINATED WORK OF WATER TRANSPORT

    Directory of Open Access Journals (Sweden)

    O. V. Shcherbina

    2018-02-01

    Full Text Available Purpose. The study aims to develop a formulation methodology for ship selection in the coordinated work of sea and river transport using a heuristic approach. Methodology. To realize the purpose set in the study, the authors carried out an analysis of domestic and foreign literature sources on the current topic, studied specifics and conditions for the effective operation of marine mono-hulled ships and composite tug/barge towing ones. Findings. The analysis results allowed formulating the heuristics methods that ensure the selection of the type sizes of tug/barge towing ships for the mixed «river-sea» navigation from the priority range of ships of the existing fleet. The proposed method makes it possible to select ships in a more appropriate manner according to the established scheme of work. Rational combinations of technical and operational characteristics of such pairs as «barges and tows», «tug/barge towing ship and sea-going ship», «tug/barge towing ship and restrictive characteristics of the area of navigation» are a prerequisite for the shipping company profit growth by increasing the capacity of ships. Originality. For the first time, the authors applied a heuristic approach to the selection of tug/barge towing ships and sea-going ones for coordinated work with the performance of cargo operations on the raid of the estuary port when transporting bulk goods. The basis of the approach is the selection of a rational mix of technical and operational characteristics of barges and tugs. The proposed approach allows determining the best combination of ship type sizes in the organization of coordinated work of sea and river transport. At the same time, the continuity of the goods transportation process from the sea ports to the river ones located in the depth of the country (and in the opposite direction is ensured. Practical value. The presented methodology is a logical continuation of the cycle of studies performed by the authors. The

  4. LOCFES-B: A program for solving the one-dimensional particle transport equation with user-selected CLOF methods

    International Nuclear Information System (INIS)

    Jarvis, R.D.; Nelson, P.

    1995-01-01

    LOCFES-B solves the steady-state, monoenergetic and azimuthally symmetric neutral-particle transport equation in one-dimensional plane-parallel geometry. LOCFES-B is designed to facilitate testing and comparison of different spatial approximations in neutron transport. Accordingly, it permits performance of user-provided CLOF spatial approximations to be compared directly on successively refined mesh sizes and user-input physical problems with automatic comparison of results. if desired, to user-supplied benchmark results

  5. Genome-Wide Characterization of Major Intrinsic Proteins in Four Grass Plants and Their Non-Aqua Transport Selectivity Profiles with Comparative Perspective.

    Directory of Open Access Journals (Sweden)

    Abul Kalam Azad

    Full Text Available Major intrinsic proteins (MIPs, commonly known as aquaporins, transport not only water in plants but also other substrates of physiological significance and heavy metals. In most of the higher plants, MIPs are divided into five subfamilies (PIPs, TIPs, NIPs, SIPs and XIPs. Herein, we identified 68, 42, 38 and 28 full-length MIPs, respectively in the genomes of four monocot grass plants, specifically Panicum virgatum, Setaria italica, Sorghum bicolor and Brachypodium distachyon. Phylogenetic analysis showed that the grass plants had only four MIP subfamilies including PIPs, TIPs, NIPs and SIPs without XIPs. Based on structural analysis of the homology models and comparing the primary selectivity-related motifs [two NPA regions, aromatic/arginine (ar/R selectivity filter and Froger's positions (FPs] of all plant MIPs that have been experimentally proven to transport non-aqua substrates, we predicted the transport profiles of all MIPs in the four grass plants and also in eight other plants. Groups of MIP subfamilies based on ar/R selectivity filter and FPs were linked to the non-aqua transport profiles. We further deciphered the substrate selectivity profiles of the MIPs in the four grass plants and compared them with their counterparts in rice, maize, soybean, poplar, cotton, Arabidopsis thaliana, Physcomitrella patens and Selaginella moellendorffii. In addition to two NPA regions, ar/R filter and FPs, certain residues, especially in loops B and C, contribute to the functional distinctiveness of MIP groups. Expression analysis of transcripts in different organs indicated that non-aqua transport was related to expression of MIPs since most of the unexpressed MIPs were not predicted to facilitate the transport of non-aqua molecules. Among all MIPs in every plant, TIP (BdTIP1;1, SiTIP1;2, SbTIP2;1 and PvTIP1;2 had the overall highest mean expression. Our study generates significant information for understanding the diversity, evolution, non

  6. Fate and transport of selected estrogen compounds in Hawaii soils: Effect of soil type and macropores

    Science.gov (United States)

    D'Alessio, Matteo; Vasudevan, Dharni; Lichwa, Joseph; Mohanty, Sanjay K.; Ray, Chittaranjan

    2014-10-01

    The fate and transport of estrogen compounds in the environment is of increasing concern due to their potential impact on freshwater organisms, ecosystems and human health. The behavior of these compounds in batch experiments suggests low mobility, while field studies indicate the persistence of estrogen compounds in the soil with the possibility of migration to surface water as well as groundwater. To better understand the movement of these chemicals through soils, we examined their transport in three different Hawaiian soils and two aqueous matrices. The three different soils used were an Oxisol, a Mollisol and a cinder, characterized by different mineralogical properties and collected at depths of 60-90 cm and 210-240 cm. Two liquid matrices were used; deionized (DI) water containing calcium chloride (CaCl2), and recycled water collected from a wastewater treatment facility. The experiments were conducted in packed and structured columns. Non-equilibrium conditions were observed during the study, especially in the structured soil. This is believed to be primarily related to the presence of macropores in the soil. The presence of macropores resulted in reduced contact time between soil and estrogens, which facilitated their transport. We found that the organic carbon content and mineralogical composition of the soils had a profound effect on the transport of the estrogens. The mobility of estrone (E1) and 17β-estradiol (E2) was greater in cinder than in the other soils. In column experiments with recycled water, earlier breakthrough peaks and longer tails of estrogens were produced compared to those observed using DI water. The use of recycled water for agricultural purposes and the siting of septic tanks and cesspools should be critically reviewed in light of these findings, especially in areas where groundwater is the primary source of potable water, such as Hawaii.

  7. Fate and transport of selected estrogen compounds in Hawaii soils: effect of soil type and macropores.

    Science.gov (United States)

    D'Alessio, Matteo; Vasudevan, Dharni; Lichwa, Joseph; Mohanty, Sanjay K; Ray, Chittaranjan

    2014-10-01

    The fate and transport of estrogen compounds in the environment is of increasing concern due to their potential impact on freshwater organisms, ecosystems and human health. The behavior of these compounds in batch experiments suggests low mobility, while field studies indicate the persistence of estrogen compounds in the soil with the possibility of migration to surface water as well as groundwater. To better understand the movement of these chemicals through soils, we examined their transport in three different Hawaiian soils and two aqueous matrices. The three different soils used were an Oxisol, a Mollisol and a cinder, characterized by different mineralogical properties and collected at depths of 60-90 cm and 210-240 cm. Two liquid matrices were used; deionized (DI) water containing calcium chloride (CaCl2), and recycled water collected from a wastewater treatment facility. The experiments were conducted in packed and structured columns. Non-equilibrium conditions were observed during the study, especially in the structured soil. This is believed to be primarily related to the presence of macropores in the soil. The presence of macropores resulted in reduced contact time between soil and estrogens, which facilitated their transport. We found that the organic carbon content and mineralogical composition of the soils had a profound effect on the transport of the estrogens. The mobility of estrone (E1) and 17β-estradiol (E2) was greater in cinder than in the other soils. In column experiments with recycled water, earlier breakthrough peaks and longer tails of estrogens were produced compared to those observed using DI water. The use of recycled water for agricultural purposes and the siting of septic tanks and cesspools should be critically reviewed in light of these findings, especially in areas where groundwater is the primary source of potable water, such as Hawaii. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Behavioral performance follows the time course of neural facilitation and suppression during cued shifts of feature-selective attention.

    Science.gov (United States)

    Andersen, S K; Müller, M M

    2010-08-03

    A central question in the field of attention is whether visual processing is a strictly limited resource, which must be allocated by selective attention. If this were the case, attentional enhancement of one stimulus should invariably lead to suppression of unattended distracter stimuli. Here we examine voluntary cued shifts of feature-selective attention to either one of two superimposed red or blue random dot kinematograms (RDKs) to test whether such a reciprocal relationship between enhancement of an attended and suppression of an unattended stimulus can be observed. The steady-state visual evoked potential (SSVEP), an oscillatory brain response elicited by the flickering RDKs, was measured in human EEG. Supporting limited resources, we observed both an enhancement of the attended and a suppression of the unattended RDK, but this observed reciprocity did not occur concurrently: enhancement of the attended RDK started at 220 ms after cue onset and preceded suppression of the unattended RDK by about 130 ms. Furthermore, we found that behavior was significantly correlated with the SSVEP time course of a measure of selectivity (attended minus unattended) but not with a measure of total activity (attended plus unattended). The significant deviations from a temporally synchronized reciprocity between enhancement and suppression suggest that the enhancement of the attended stimulus may cause the suppression of the unattended stimulus in the present experiment.

  9. Game Theoretical Approaches for Transport-Aware Channel Selection in Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Chen Shih-Ho

    2010-01-01

    Full Text Available Effectively sharing channels among secondary users (SUs is one of the greatest challenges in cognitive radio network (CRN. In the past, many studies have proposed channel selection schemes at the physical or the MAC layer that allow SUs swiftly respond to the spectrum states. However, they may not lead to enhance performance due to slow response of the transport layer flow control mechanism. This paper presents a cross-layer design framework called Transport Aware Channel Selection (TACS scheme to optimize the transport throughput based on states, such as RTT and congestion window size, of TCP flow control mechanism. We formulate the TACS problem as two different game theoretic approaches: Selfish Spectrum Sharing Game (SSSG and Cooperative Spectrum Sharing Game (CSSG and present novel distributed heuristic algorithms to optimize TCP throughput. Computer simulations show that SSSG and CSSG could double the SUs throughput of current MAC-based scheme when primary users (PUs use their channel infrequently, and with up to 12% to 100% throughput increase when PUs are more active. The simulation results also illustrated that CSSG performs up to 20% better than SSSG in terms of the throughput.

  10. Theoretical analysis of selectivity mechanisms in molecular transport through channels and nanopores

    International Nuclear Information System (INIS)

    Agah, Shaghayegh; Pasquali, Matteo; Kolomeisky, Anatoly B.

    2015-01-01

    Selectivity is one of the most fundamental concepts in natural sciences, and it is also critically important in various technological, industrial, and medical applications. Although there are many experimental methods that allow to separate molecules, frequently they are expensive and not efficient. Recently, a new method of separation of chemical mixtures based on utilization of channels and nanopores has been proposed and successfully tested in several systems. However, mechanisms of selectivity in the molecular transport during the translocation are still not well understood. Here, we develop a simple theoretical approach to explain the origin of selectivity in molecular fluxes through channels. Our method utilizes discrete-state stochastic models that take into account all relevant chemical transitions and can be solved analytically. More specifically, we analyze channels with one and two binding sites employed for separating mixtures of two types of molecules. The effects of the symmetry and the strength of the molecular-pore interactions are examined. It is found that for one-site binding channels, the differences in the strength of interactions for two species drive the separation. At the same time, in more realistic two-site systems, the symmetry of interaction potential becomes also important. The most efficient separation is predicted when the specific binding site is located near the entrance to the nanopore. In addition, the selectivity is higher for large entrance rates into the channel. It is also found that the molecular transport is more selective for repulsive interactions than for attractive interactions. The physical-chemical origin of the observed phenomena is discussed

  11. A Major Facilitator Superfamily Transporter-Mediated Resistance to Oxidative Stress and Fungicides Requires Yap1, Skn7, and MAP Kinases in the Citrus Fungal Pathogen Alternaria alternata.

    Directory of Open Access Journals (Sweden)

    Li-Hung Chen

    Full Text Available Major Facilitator Superfamily (MFS transporters play an important role in multidrug resistance in fungi. We report an AaMFS19 gene encoding a MFS transporter required for cellular resistance to oxidative stress and fungicides in the phytopathogenic fungus Alternaria alternata. AaMFS19, containing 12 transmembrane domains, displays activity toward a broad range of substrates. Fungal mutants lacking AaMFS19 display profound hypersensitivities to cumyl hydroperoxide, potassium superoxide, many singlet oxygen-generating compounds (eosin Y, rose Bengal, hematoporphyrin, methylene blue, and cercosporin, and the cell wall biosynthesis inhibitor, Congo red. AaMFS19 mutants also increase sensitivity to copper ions, clotrimazole, fludioxonil, and kocide fungicides, 2-chloro-5-hydroxypyridine (CHP, and 2,3,5-triiodobenzoic acid (TIBA. AaMFS19 mutants induce smaller necrotic lesions on leaves of a susceptible citrus cultivar. All observed phenotypes in the mutant are restored by introducing and expressing a wild-type copy of AaMFS19. The wild-type strain of A. alternata treated with either CHP or TIBA reduces radial growth and formation and germination of conidia, increases hyphal branching, and results in decreased expression of the AaMFS19 gene. The expression of AaMFS19 is regulated by the Yap1 transcription activator, the Hog1 and Fus3 mitogen-activated protein (MAP kinases, the 'two component' histidine kinase, and the Skn7 response regulator. Our results demonstrate that A. alternata confers resistance to different chemicals via a membrane-bound MFS transporter.

  12. Localization and regulation of a facilitative urea transporter in the kidney of the red-eared slider turtle (Trachemys scripta elegans).

    Science.gov (United States)

    Uchiyama, Minoru; Kikuchi, Ryosuke; Konno, Norifumi; Wakasugi, Tatsuya; Matsuda, Kouhei

    2009-01-01

    Urea is the major excretory end product of nitrogen metabolism in most chelonian reptiles. In the present study, we report the isolation of a 1632 base pair cDNA from turtle kidney with one open reading frame putatively encoding a 403-residue protein, the turtle urea transporter (turtle UT). The first cloned reptilian UT has high homology with UTs (facilitated urea transporters) cloned from vertebrates, and most closely resembles the UT-A subfamily. Injection of turtle UT cRNA into Xenopus oocytes induced a 6-fold increase in [(14)C]urea uptake that was inhibited by phloretin. The turtle UT mRNA expression and tissue distribution were examined by RT-PCR with total RNA from various tissues. Expression of turtle UT mRNA was restricted to the kidney, and no signal was detected in the other tissues, such as brain, heart, alimentary tract and urinary bladder. An approximately 58 kDa protein band was detected in membrane fractions of the kidney by western blot using an affinity-purified antibody that recognized turtle UT expressed in Xenopus oocytes. In an immunohistochemical study using the anti-turtle UT antibody, UT-immunopositive cells were observed along the distal tubule but not in the collecting duct. In turtles under dry conditions, plasma osmolality and urea concentration increased, and using semi-quantitative RT-PCR the UT mRNA expression level in the kidney was found to increase 2-fold compared with control. The present results, taken together, suggest that the turtle UT probably contributes to urea transport in the distal tubule segments of the kidney in response to hyperosmotic stress under dry conditions.

  13. Preparation and Characterization of Facilitated Transport Membranes Composed of Chitosan-Styrene and Chitosan-Acrylonitrile Copolymers Modified by Methylimidazolium Based Ionic Liquids for CO2 Separation from CH4 and N2

    Directory of Open Access Journals (Sweden)

    Ksenia V. Otvagina

    2016-06-01

    Full Text Available CO2 separation was found to be facilitated by transport membranes based on novel chitosan (CS–poly(styrene (PS and chitosan (CS–poly(acrylonitrile (PAN copolymer matrices doped with methylimidazolium based ionic liquids: [bmim][BF4], [bmim][PF6], and [bmim][Tf2N] (IL. CS plays the role of biodegradable film former and selectivity promoter. Copolymers were prepared implementing the latest achievements in radical copolymerization with chosen monomers, which enabled the achievement of outstanding mechanical strength values for the CS-based membranes (75–104 MPa for CS-PAN and 69–75 MPa for CS-PS. Ionic liquid (IL doping affected the surface and mechanical properties of the membranes as well as the gas separation properties. The highest CO2 permeability 400 Barrers belongs to CS-b-PS/[bmim][BF4]. The highest selectivity α (CO2/N2 = 15.5 was achieved for CS-b-PAN/[bmim][BF4]. The operational temperature of the membranes is under 220 °C.

  14. Interactive FORTRAN IV computer programs for the thermodynamic and transport properties of selected cryogens (fluids pack)

    Science.gov (United States)

    Mccarty, R. D.

    1980-01-01

    The thermodynamic and transport properties of selected cryogens had programmed into a series of computer routines. Input variables are any two of P, rho or T in the single phase regions and either P or T for the saturated liquid or vapor state. The output is pressure, density, temperature, entropy, enthalpy for all of the fluids and in most cases specific heat capacity and speed of sound. Viscosity and thermal conductivity are also given for most of the fluids. The programs are designed for access by remote terminal; however, they have been written in a modular form to allow the user to select either specific fluids or specific properties for particular needs. The program includes properties for hydrogen, helium, neon, nitrogen, oxygen, argon, and methane. The programs include properties for gaseous and liquid states usually from the triple point to some upper limit of pressure and temperature which varies from fluid to fluid.

  15. Transport and energy selection of laser generated protons for postacceleration with a compact linac

    Science.gov (United States)

    Sinigardi, Stefano; Turchetti, Giorgio; Londrillo, Pasquale; Rossi, Francesco; Giove, Dario; De Martinis, Carlo; Sumini, Marco

    2013-03-01

    Laser accelerated proton beams have a considerable potential for various applications including oncological therapy. However, the most consolidated target normal sheath acceleration regime based on irradiation of solid targets provides an exponential energy spectrum with a significant divergence. The low count number at the cutoff energy seriously limits at present its possible use. One realistic scenario for the near future is offered by hybrid schemes. The use of transport lines for collimation and energy selection has been considered. We present here a scheme based on a high field pulsed solenoid and collimators which allows one to select a beam suitable for injection at 30 MeV into a compact linac in order to double its energy while preserving a significant intensity. The results are based on a fully 3D simulation starting from laser acceleration.

  16. Transport and energy selection of laser generated protons for postacceleration with a compact linac

    Directory of Open Access Journals (Sweden)

    Stefano Sinigardi

    2013-03-01

    Full Text Available Laser accelerated proton beams have a considerable potential for various applications including oncological therapy. However, the most consolidated target normal sheath acceleration regime based on irradiation of solid targets provides an exponential energy spectrum with a significant divergence. The low count number at the cutoff energy seriously limits at present its possible use. One realistic scenario for the near future is offered by hybrid schemes. The use of transport lines for collimation and energy selection has been considered. We present here a scheme based on a high field pulsed solenoid and collimators which allows one to select a beam suitable for injection at 30 MeV into a compact linac in order to double its energy while preserving a significant intensity. The results are based on a fully 3D simulation starting from laser acceleration.

  17. 76 FR 11554 - Fiscal Year 2010 Public Transportation on Indian Reservations Program Project Selections

    Science.gov (United States)

    2011-03-02

    ... DEPARTMENT OF TRANSPORTATION Federal Transit Administration Fiscal Year 2010 Public Transportation... Interior for public transportation capital projects, operating costs and planning activities that are... authorized by the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users...

  18. 77 FR 547 - Fiscal Year 2011 Public Transportation on Indian Reservations Program Project Selections

    Science.gov (United States)

    2012-01-05

    ... DEPARTMENT OF TRANSPORTATION Federal Transit Administration Fiscal Year 2011 Public Transportation... 5311 (c), Public Transportation on Indian Reservations program funds in support of the Tribal Transit... for public transportation services on and around Indian reservations. FOR FURTHER INFORMATION CONTACT...

  19. A method for selection of spent nuclear fuel (SNF) transportation route considering socioeconomic cost based on contingent valuation method (CVM)

    International Nuclear Information System (INIS)

    Kim, Young Sik

    2008-02-01

    A transportation of SNF may cause an additional radiation exposure to human beings. It means that the radiological risk should be estimated and managed quantitatively for the public who live near the shipments route. Before the SNF transportation is performed, the route selection is concluded based on the radiological risk estimated with RADTRAN code in existing method generally. It means the existing method for route selection is based only on the radiological health risk but there are not only the impacts related to the radiological health risk but also the socioeconomic impacts related to the cost. In this study, a new method and its numerical formula for route selection on transporting SNF is proposed based on cost estimation because there are several costs in transporting SNF. The total cost consists of radiological health cost, transportation cost, and socioeconomic cost. Each cost is defined properly to the characteristics of SNF transportation and many coefficients and variables describing the meaning of each cost are obtained or estimated through many surveys. Especially to get the socioeconomic cost, contingent valuation method (CVM) is used with a questionnaire. The socioeconomic cost estimation is the most important part of the total cost originated from transporting SNF because it is a very dominant cost in the total cost. The route selection regarding SNF transportation can be supported with the proposed method reasonably and unnecessary or exhausting controversies about the shipments could be avoided

  20. Strategic decisions in transport: a case study for a naval base selection in Brazil

    Directory of Open Access Journals (Sweden)

    Amaury Caruzzo

    2016-04-01

    Full Text Available A decision on a military strategic environment, such as the selection of a new naval base, is a complex process and involves various criteria. In this context, few studies are available on the problems of military-naval transport decisions. Therefore, the aim of this paper is to present a maritime transport case study using a multi-methodology framework in a process of strategic decision making in logistics. Through a review of the literature, normative documents from the Brazilian armed forces, and interviews with military officers, criteria and preferences were identified and a hierarchical structure was constructed for a case study in the Brazilian Navy–the location of the second Fleet Headquarters. The results indicated that São Marcos Bay, in Maranhão State, was the best location among the alternatives. The multi-criteria approach was shown to be a valuable tool in assisting the decision making process and to understand the trade-offs between strategic and operational criteria in a transport decision.

  1. LOCFES-B: Solving the one-dimensional transport equation with user-selected spatial approximations

    International Nuclear Information System (INIS)

    Jarvis, R.D.; Nelson, P.

    1993-01-01

    Closed linear one-cell functional (CLOF) methods constitute an abstractly defined class of spatial approximations to the one-dimensional discrete ordinates equations of linear particle transport that encompass, as specific instances, the vast majority of the spatial approximations that have been either used or suggested in the computational solution of these equations. A specific instance of the class of CLOF methods is defined by a (typically small) number of functions of the cell width, total cross section, and direction cosine of particle motion. The LOCFES code takes advantage of the latter observation by permitting the use, within a more-or-less standard source iteration solution process, of an arbitrary CLOF method as defined by a user-supplied subroutine. The design objective of LOCFES was to provide automated determination of the order of accuracy (i.e., order of the discretization error) in the fine-mesh limit for an arbitrary user-selected CLOF method. This asymptotic order of accuracy is one widely used measure of the merit of a spatial approximation. This paper discusses LOCFES-B, which is a code that uses methods developed in LOCFES to solve one-dimensional linear particle transport problems with any user-selected CLOF method. LOCFES-B provides automatic solution of a given problem to within an accuracy specified by user input and provides comparison of the computational results against results from externally provided benchmark results

  2. Divalent Metal Ion Transport across Large Biological Ion Channels and Their Effect on Conductance and Selectivity

    Directory of Open Access Journals (Sweden)

    Elena García-Giménez

    2012-01-01

    Full Text Available Electrophysiological characterization of large protein channels, usually displaying multi-ionic transport and weak ion selectivity, is commonly performed at physiological conditions (moderate gradients of KCl solutions at decimolar concentrations buffered at neutral pH. We extend here the characterization of the OmpF porin, a wide channel of the outer membrane of E. coli, by studying the effect of salts of divalent cations on the transport properties of the channel. The regulation of divalent cations concentration is essential in cell metabolism and understanding their effects is of key importance, not only in the channels specifically designed to control their passage but also in other multiionic channels. In particular, in porin channels like OmpF, divalent cations modulate the efficiency of molecules having antimicrobial activity. Taking advantage of the fact that the OmpF channel atomic structure has been resolved both in water and in MgCl2 aqueous solutions, we analyze the single channel conductance and the channel selectivity inversion aiming to separate the role of the electrolyte itself, and the counterion accumulation induced by the protein channel charges and other factors (binding, steric effects, etc. that being of minor importance in salts of monovalent cations become crucial in the case of divalent cations.

  3. SELECTED ASPECTS OF THE IMPLEMENTATION OF ACTIVE MARKETING CAMPAIGN TO RAISE AWARENESS AND PROMOTE PUBLIC TRANSPORT SERVICES IN RURAL AREAS

    Directory of Open Access Journals (Sweden)

    Katarzyna NOSAL

    2016-09-01

    Full Text Available The article presents selected aspects of the implementation of the EU’s SmartMove project, which aims to promote feeder public transport systems in rural areas through the implementation of an active marketing campaign (AMC. Campaigns of this type are connected with providing general and personalized information concerning the functioning of public transport services. In the article, characteristics of one of the implementation areas of the project are presented, namely, the Liszki district near Cracow. Transport services were also evaluated. In addition, selected results are presented from a survey that was conducted among residents of the area from the point of view of the implementation of the AMC. The results concerned data about the means of transport that were currently used for travelling, the knowledge of bus services, the reasons for their use and the factors that might encourage residents to use public transport

  4. Mixed matrix membranes with fast and selective transport pathways for efficient CO2 separation

    Science.gov (United States)

    Hou, Jinpeng; Li, Xueqin; Guo, Ruili; Zhang, Jianshu; Wang, Zhongming

    2018-03-01

    To improve CO2 separation performance, porous carbon nanosheets (PCNs) were used as a filler into a Pebax MH 1657 (Pebax) matrix, fabricating mixed matrix membranes (MMMs). The PCNs exhibited a preferential horizontal orientation within the Pebax matrix because of the extremely large 2D plane and nanoscale thickness of the matrix. Therefore, the micropores of the PCNs provided fast CO2 transport pathways, which led to increased CO2 permeability. The reduced pore size of the PCNs was a consequence of the overlapping of PCNs and the polymer chains penetrating into the pores of the PCNs. The reduction in the pore size of the PCNs improved the CO2/gas selectivity. As a result, the CO2 permeability and CO2/CH4 selectivity of the Pebax membrane with 10 wt% PCNs-loading (Pebax-PCNs-10) were 520 barrer and 51, respectively, for CO2/CH4 mixed-gas. The CO2 permeability and CO2/N2 selectivity of the Pebax-PCNs-10 membrane were 614 barrer and 61, respectively, for CO2/N2 mixed-gas.

  5. BioEnergy transport systems. Life cycle assessment of selected bioenergy systems

    Energy Technology Data Exchange (ETDEWEB)

    Forsberg, Goeran

    1999-07-01

    Biomass for energy conversion is usually considered as a local resource. With appropriate logistic systems, access to biomass can be improved over a large geographical area. In this study, life cycle assessment (LCA) has been used as method to investigate the environmental impacts of selected bioenergy transport chains. As a case study, chains starting in Sweden and ending in Holland have been investigated. Biomass originates from tree sections or forest residues, the latter upgraded to bales or pellets. The study is concentrated on production of electricity, hot cooling water is considered as a loss. Electricity is, as the main case, produced from solid biomass in the importing country. Electricity can also be produced in the country of origin and exported via the trans-national grid as transportation media. As an alternative, a comparison is made with a coal cycle. The results show that contribution of emissions from long-range transportation is of minor importance. The use of fuels and electricity for operating machines and transportation carriers requires a net energy input in bioenergy systems which amounts to typically 7-9% of delivered electrical energy from the system. Emissions of key substances such as NO{sub x}, CO, S, hydrocarbons, and particles are low. Emissions of CO{sub 2} from biocombustion are considered to be zero since there is approximately no net contribution of carbon to the biosphere in an energy system based on biomass. A method to quantify non-renewability is presented. For coal, the non-renewability factor is calculated to be 110%. For most of the cases with bioenergy, the non-renewability factor is calculated to be between 6 and 11%. Reclamation of biomass results in certain losses of nutrients such as nitrogen, phosphorus and base cations such as K, Ca and Mg. These are balanced by weathering, vitalisation or ash recirculation procedures. Withdrawal of N from the ecological system is approximately 10 times the load from the technical

  6. Variation in the serotonin transporter gene modulates selective attention to threat.

    Science.gov (United States)

    Osinsky, Roman; Reuter, Martin; Küpper, Yvonne; Schmitz, Anja; Kozyra, Eva; Alexander, Nina; Hennig, Jürgen

    2008-08-01

    The 5-HTTLPR is an insertion/deletion polymorphism in the promoter region of the serotonin transporter gene. Prior research has revealed associations between the short-allele variant of this polymorphism, enhanced self-reported negative emotionality, and hypersensitivity of fear relevant neural circuits. In a sample of 50 healthy women we examined the role of 5-HTTLPR for cognitive-affective processing of phylogenetical fear-relevant stimuli (spiders) in a dot probe task. In contrast to homozygote long-allele carriers (ll), participants carrying at least 1 short allele (ss and sl) selectively shifted attention toward pictures of spiders, when these were presented for a duration of 2,000 ms. These results argue for an involvement of 5-HTTLPR in cognitive processing of threatening stimuli and thus, underpin its general role for individual differences in negative affect.

  7. Selecting the minimum risk route in the transportation of hazardous materials

    Directory of Open Access Journals (Sweden)

    Marijan Žura

    1992-12-01

    Full Text Available The transportation of hazardous materials is a broad and complex topic. Percent and iveight of accidents of vehicles carrying dangerous goods are growing fast. Modern computer based information system for dangerous materials management is becoming more and more important. In this paper I present an interactive software system for minimum risk route selection based on the PC ARC/INFO. The model computes optimal path based on accident probability is computed from traffic accident rates, highway operational speed, traffic volume and technical characteristic of the roadwidth, radius and slope. Dangerous goods are classified into nine classes according to their impact to different sensible environment elements. Those sensible elements are drinking water resourses, natural heritage, forestry, agricultural areas, cultural heritage, urban areas and tourist resorts. Some results of system implementation on Slovenia road network are be presented.

  8. Transport and selective chaining of bidisperse particles in a travelling wave potential.

    Science.gov (United States)

    Tierno, Pietro; Straube, Arthur V

    2016-05-01

    We combine experiments, theory and numerical simulation to investigate the dynamics of a binary suspension of paramagnetic colloidal particles dispersed in water and transported above a stripe-patterned magnetic garnet film. The substrate generates a one-dimensional periodic energy landscape above its surface. The application of an elliptically polarized rotating magnetic field causes the landscape to translate, inducing direct transport of paramagnetic particles placed above the film. The ellipticity of the applied field can be used to control and tune the interparticle interactions, from net repulsive to net attractive. When considering particles of two distinct sizes, we find that, depending on their elevation above the surface of the magnetic substrate, the particles feel effectively different potentials, resulting in different mobilities. We exploit this feature to induce selective chaining for certain values of the applied field parameters. In particular, when driving two types of particles, we force only one type to condense into travelling parallel chains. These chains confine the movement of the other non-chaining particles within narrow colloidal channels. This phenomenon is explained by considering the balance of pairwise magnetic forces between the particles and their individual coupling with the travelling landscape.

  9. An approach to selecting routes over which to transport excess salt from the Deaf Smith County Site

    International Nuclear Information System (INIS)

    1987-09-01

    This report presents an approach to be utilized in the identification of rail and/or highway routes for the disposal of waste salt and other salt contaminated material from repository construction. Relevant issues regarding salt transport also are identified. The report identifies a sequence of activities that precede actual route selection, i.e., final selection of a salt disposal method and its location, refined estimates of salt shipment volume and schedule, followed by selection of rail or truck or a combination thereof, as the preferred transport mode. After these factors are known, the route selection process can proceed. Chapter 2.0 of this report identifies directives and requirements that potentially could affect salt transport from the Deaf Smith site. A summary of salt disposal alternatives and reference cases is contained in Chapter 3.0. Chapter 4.0 identifies and discusses current methods of salt handling and transport in the United States, and also provides some perspective as to the volume of excess salt to be transported from the Deaf Smith site relative to current industry practices. Chapter 5.0 identifies an approach to the salt transportation issue, and suggests one system for evaluating alternative highway routes for truck shipments

  10. Selection of distribution coefficients for contaminant fate and transport calculations: Strontium as a case study

    International Nuclear Information System (INIS)

    Kaplan, D.I.; Krupka, K.M.; Serne, R.J.

    1997-01-01

    As part of an ongoing project funded by a cooperative effort involving the Office of Radiation and Indoor Air (ORIA) of the U.S. Environmental Protection Agency (EPA), the Office of Environmental Restoration (EM-40) of the Department of Energy (DOE), and the Nuclear Regulatory Agency (NRC), distribution coefficient (K d ) values are being compiled from the literature to develop provisional tables for cadmium, cesium, chromium, lead, plutonium, strontium, thorium, and uranium. The tables are organized according to important aqueous- and solid-phase parameters affecting the sorption of these contaminants. These parameters, which vary with contaminant, include pH and redox conditions; cation exchange capacity (CEC); presence of iron-oxide, aluminum-oxide, clay, and mica minerals; organic matter content; and solution concentrations of contaminants, competing ions, and complexing ligands. Sorption information compiled for strontium is used to illustrate our approach. The strontium data show how selected geochemical parameters (i.e., CEC, pH, and clay content) affect Strontium K d values and the selection of open-quote default close-quote K d values needed for modeling contaminant transport and risks at sites for which site specific data are lacking. Results of our evaluation may be used by site management and technical staff to assess contaminant fate, migration, and risk calculations in support of site remediation and waste management decisions

  11. 78 FR 1301 - Fiscal Year 2012 Public Transportation on Indian Reservations Program Project Selections

    Science.gov (United States)

    2013-01-08

    ... DEPARTMENT OF TRANSPORTATION Federal Transit Administration Fiscal Year 2012 Public Transportation... Affairs (BIA) in the U.S. Department of the Interior for public transportation. An additional $500,000 is... Fiscal Year 2013 Public Transportation on Indian Reservations Program, which: (1) Introduces FTA's...

  12. Hepatitis C Virus Proteins Interact with the Endosomal Sorting Complex Required for Transport (ESCRT Machinery via Ubiquitination To Facilitate Viral Envelopment

    Directory of Open Access Journals (Sweden)

    Rina Barouch-Bentov

    2016-11-01

    Full Text Available Enveloped viruses commonly utilize late-domain motifs, sometimes cooperatively with ubiquitin, to hijack the endosomal sorting complex required for transport (ESCRT machinery for budding at the plasma membrane. However, the mechanisms underlying budding of viruses lacking defined late-domain motifs and budding into intracellular compartments are poorly characterized. Here, we map a network of hepatitis C virus (HCV protein interactions with the ESCRT machinery using a mammalian-cell-based protein interaction screen and reveal nine novel interactions. We identify HRS (hepatocyte growth factor-regulated tyrosine kinase substrate, an ESCRT-0 complex component, as an important entry point for HCV into the ESCRT pathway and validate its interactions with the HCV nonstructural (NS proteins NS2 and NS5A in HCV-infected cells. Infectivity assays indicate that HRS is an important factor for efficient HCV assembly. Specifically, by integrating capsid oligomerization assays, biophysical analysis of intracellular viral particles by continuous gradient centrifugations, proteolytic digestion protection, and RNase digestion protection assays, we show that HCV co-opts HRS to mediate a late assembly step, namely, envelopment. In the absence of defined late-domain motifs, K63-linked polyubiquitinated lysine residues in the HCV NS2 protein bind the HRS ubiquitin-interacting motif to facilitate assembly. Finally, ESCRT-III and VPS/VTA1 components are also recruited by HCV proteins to mediate assembly. These data uncover involvement of ESCRT proteins in intracellular budding of a virus lacking defined late-domain motifs and a novel mechanism by which HCV gains entry into the ESCRT network, with potential implications for other viruses.

  13. Engineering Rhodosporidium toruloides with a membrane transporter facilitates production and separation of carotenoids and lipids in a bi-phasic culture.

    Science.gov (United States)

    Lee, Jaslyn J L; Chen, Liwei; Cao, Bin; Chen, Wei Ning

    2016-01-01

    The oleaginous yeast Rhodosporidium toruloides has great biotechnological potential. It accumulates a high amount of lipids which can be used for biofuels and also produces carotenoids which are valuable in the food and pharmaceutical industry. However, the location of these two hydrophobic products in the cell membrane prohibits its efficient harvesting and separation. Here, the transporter Pdr10 was engineered into R. toruloides and cultured in two-phase media containing oil. This enabled the production and in situ export of carotenoids into the oil and concurrent separation from intracellular lipids in the cells. When Pdr10 strain was cultured in the two-phase media, carotenoids and fatty acids yield increased from 1.9 to 2.9 μg/mg and 0.07 to 0.09 mg/mg, respectively. A total of 1.8 μg/mg carotenoids was exported by Pdr10 strain, as compared to 0.3 μg/mg in the wild type. In the Pdr10 strain, the composition of carotenoids and fatty acid it produced also changed. Torulene became the major carotene produced instead of torularhodin. Also, the unsaturated fatty acid C18:2 became the dominant fatty acid produced instead of the saturated C16:0, which was similar to the grape seed oil used in the two-phase media. This indicated that oil was being consumed by the cells, which was supported by the increased intracellular glycerol levels detected by gas chromatography-mass spectrometry (GC-MS). Our approach represents an easy and greener extraction method which could serve to increase the yield and facilitate separation of carotenoids and fatty acids.

  14. An assessment of gender sensitivity in a selection of transport surveys

    CSIR Research Space (South Africa)

    Mashiri, M

    2006-12-01

    Full Text Available at worst (Mashiri, 2001). The starting point for engendering transport data has generally been to gender-disaggregate figures and analyses in transport surveys (ibid). Gender differences in time spent on travel and transport, as well as socio...-economic and health costs relating to transport, have thus far primarily been highlighted in gender-disaggregated quantitative transport data (Venter et al, 2006). Gender- disaggregated travel time data has, in particular, raised awareness of women’s significant...

  15. Selective binding of 2-[125I]iodo-nisoxetine to norepinephrine transporters in the brain

    International Nuclear Information System (INIS)

    Kung, M.-P.; Choi, Seok-Rye; Hou, Catherine; Zhuang, Z.-P.; Foulon, Catherine; Kung, Hank F.

    2004-01-01

    A radioiodinated ligand, (R)-N-methyl-(2-[ 125 I]iodo-phenoxy)-3-phenylpropylamine, [ 125 I]2-INXT, targeting norepinephrine transporters (NET), was successfully prepared. A no-carrier-added product, [ 125 I]2-INXT, displayed a saturable binding with a high affinity (K d =0.06 nM) in the homogenates prepared from rat cortical tissues as well as from LLC-PK 1 cells expressing NET. A relatively low number of binding sties (B max =55 fmol/mg protein) measured with [ 125 I]2-INXT in rat cortical homogenates is consistent with the value reported for a known NET ligand, [ 3 H]nisoxetine. Competition studies with various compounds on [ 125 I]2-INXT binding clearly confirmed the pharmacological specificity and selectivity for NET binding sites. Following a tail-vein injection of [ 125 I]2-INXT in rats, a good initial brain uptake was observed (0.56% dose at 2 min) followed by a slow washout from the brain (0.2% remained at 3 hours post-injection). The hypothalamus (a NET-rich region) to striatum (a region devoid of NET) ratio was 1.5 at 3 hours post-i.v. injection. Pretreatment of rats with nisoxetine significantly inhibited the uptake of [ 125 I]2-INXT (70-100% inhibition) in locus coeruleus, hypothalamus and raphe nuclei, regions known to have a high density of NET; whereas escitalopram, a serotonin transporter ligand, did not show a similar effect. Ex vivo autoradiography of rat brain sections of [ 125 I]2-INXT (at 3 hours after an i.v. injection) displayed an excellent regional brain localization pattern corroborated to the specific NET distribution in the brain. The specific brain localization was significantly reduced by a dose of nisoxetine pretreatment. Taken together, the data suggest that [ 123 I]2-INXT may be useful for mapping NET binding sites in the brain

  16. Nuclear waste transportation package testing: A review of selected programs in the United States and abroad

    International Nuclear Information System (INIS)

    Snedeker, D.F.

    1990-12-01

    This report provides an overview of some recent nuclear waste transportation package development programs. This information is intended to aid the State of Nevada in its review of US Department of Energy (DOE) nuclear waste transportation programs. This report addresses cask testing programs in the United Kingdom and selected 1/4 and full scale testing in the US. Facilities that can provide cask testing services, both in the US and to a limited extent abroad, are identified. The costs for different type test programs are identified as a means to estimate costs for future test programs. Not addressed is the public impact such testing might have in providing an increased sense of safety or confidence. The British test program was apparently quite successful in demonstrating safety to the public at the time. There is no US test effort that is similar in scope for direct comparison. Also addressed are lessons learned from testing programs and areas that may merit possible future integrated examination. Areas that may require further examination are both technical and institutional. This report provides information which, when combined with other sources of information will enable the State of Nevada to assess the following areas: feasibility of full scale testing; costs of full scale tests; potential benefits of testing; limits that full scale testing impose; and disadvantages of emphasis on testing vs analytical solutions. This assessment will then allow the state to comment on DOE Office of Civilian Radioactive Waste Management (OCRWM) plans for the development and licensing of new shipping cask designs. These plans currently expect contractors to perform engineering testing for materials development, quarter scale model testing to validate analytical assessments and full scale prototype testing of operational features. DOE currently plans no full scale or extra-regulatory destructive testing to aid in cask licensing. 1 tab

  17. Tuning PIM-PI-Based Membranes for Highly Selective Transport of Propylene/Propane

    KAUST Repository

    Swaidan, Ramy J.

    2016-12-06

    . For the first time attempted for C3H6/C3H8 separation, high temperature heating of a PIM-PI to form thermally-rearranged and carbon molecular sieve membranes was employed. The TR membrane showed increased C3H6 permeability and about 50% losses in C3H6/C3H8 selectivity, while the CMS membrane formed at 600 oC showed modest gains in C3H6/C3H8 selectivity with significant improvements in C3H6 permeability. Finally, hybrid nanocomposite membranes incorporating a metal-organic framework structure into a PIM-PI matrix was used. ZIF-8, which has demonstrated high diffusive selectivities for C3H6/C3H8, was dispersed within the polymer, since previous work by the Koros group indicated that its incorporation into polyimide matrices can facilitate major improvements in both C3H6/C3H8 selectivity and C3H6 permeability compared to the respective neat polymer. Focus was directed towards attempting to improve polymer/nanoparticle adhesion by enhancing the interactions between the polymer and filler particles to mitigate the interfacial defects notorious in mixed-matrix membranes (MMM). To do so, ZIF-8 was dispersed into one of the best performing hydroxyl functionalized PIM-PI for the C3H6/C3H8 separation. The highest loaded mixed-matrix membrane in a glassy polymer to date of 65% (w/w) was achieved. The membranes showed pure-gas selectivities ranging from 34 with 10 Barrer at 30% loading to 43 with 38 Barrer at 65% loading. Strong performance and plasticization resistance were sustained in mixed-gas experiments even to feed pressures approaching the vapor pressure of the C3H6/C3H8 mixture, as selectivities well over 20 were achieved with high permeabilities, thereby demonstrating the potential commercial viability. Based on the work reported in this dissertation, we hope to help lay a framework to be able to tailor membrane performance and future membrane design to meet the demands of the different applications of the propylene/propane separation and hence show that there can be a

  18. Transportation

    National Research Council Canada - National Science Library

    Adams, James; Carr, Ron; Chebl, Maroun; Coleman, Robert; Costantini, William; Cox, Robert; Dial, William; Jenkins, Robert; McGovern, James; Mueller, Peter

    2006-01-01

    ...., trains, ships, etc.) and maximizing intermodal efficiency. A healthy balance must be achieved between the flow of international commerce and security requirements regardless of transportation mode...

  19. 76 FR 55886 - Selection Criteria-Transportation Infrastructure Improvements Associated With Medical Facilities...

    Science.gov (United States)

    2011-09-09

    ... applicants for funding from the Office of Economic Adjustment (OEA) for construction of Transportation... be passed through another Federal agency for implementation. Response: For direct OEA construction... accident (negative factor) of an existing or proposed transportation facility. Response: The commenter...

  20. Perceived Barriers and Facilitators of Exercise and Healthy Dietary Choices: A Study of Employees and Managers within a Large Transport Organisation

    Science.gov (United States)

    Donaldson-Feilder, Emma; Lewis, Rachel; Pavey, Louisa; Jones, Bethan; Green, Melanie; Webster, Angela

    2017-01-01

    Objective: The objective of this study was to examine employees' perceived barriers and facilitators of physical activity and healthy dietary choices, and managers' perceptions of how best to facilitate physical activity and healthy dietary choices among their team members. Design: Single time-point survey with categorical and open-ended…

  1. Relating transport modeling to nanofiltration membrane fabrication: Navigating the permeability-selectivity trade-off in desalination pretreatment

    OpenAIRE

    Labban, Omar; Lienhard, John H

    2018-01-01

    Faced with a pressing need for membranes with a higher permeability and selectivity, the field of membrane technology can benefit from a systematic framework for designing membranes with the necessary physical characteristics. In this work, we present an approach through which transport modeling is employed in fabricating specialized nanofiltration membranes, that experimentally demonstrate enhanced selectivity. Specifically, the Donnan-Steric Pore Model with dielectric exclusion (DSPM-DE) is...

  2. Transport and Environment 2011. Selected indicators for the transport sector; Samferdsel og miljoe 2011. Utvalgte indikatorer for samferdselssektoren

    Energy Technology Data Exchange (ETDEWEB)

    Brunvoll, Frode; Monsrud, Jan

    2011-06-15

    This report contains statistics and indicators for the transport sector that show the relationships between the environment and transport. Norwegian data are compared to international data. In 2008, the average daily per capita distance driven by passenger cars in Norway was 32.4 kilometres. Among the European countries, Italy had the longest daily per capita distance driven by passenger cars, 33.1 km. In 2009, the total transport demand of passenger cars in Norway was 58.3 billion passenger kilometres. This is well over ten times higher than in 1960. In 2008, the statistics show a decrease by 2 per cent in freight transport demand on road in the EU. The decrease continued with an additional decrease of 10 per cent in 2009. The financial crisis had a negative impact on the freight transport demand in Norway also, but not before 2009, when the production decreased at the same rate as in the EU. By the end of 2010, the vehicle fleet in Norway had increased to around 3.2 million, of which over 2.3 million were passenger cars. In 2009, there were 462 passenger cars per 1 000 inhabitants in Norway. In Italy there were 606, the highest in Europe. By the end of 2010, the number of diesel passenger cars were a little over 807 000, which corresponded to 35 per cent of the total number of passenger cars. The number of gasoline driven passenger cars has decreased steadily from 2004. At the end of 2010, the average age of passenger cars in Norway was 10.5 years. Gasoline driven cars had an average age of 13.0 years and diesel cars only 5.9 years. A total of 98 662 passenger cars and vans were scrapped in 2010. The average age of scrapped passenger cars was 18.4 years. As of 31 December 2010, the length of public roads in Norway was 93 509 km, of which 381 km are motorways. This is by far the shortest motorway length in the Nordic countries. The length of railways in Norway is a little over 4 000 km. Fragmentation of areas due to the expansion of transport infrastructure and

  3. Peptide Selectivity of the Proton-Coupled Oligopeptide Transporter from Neisseria meningitidis

    DEFF Research Database (Denmark)

    Sharma, Neha; Aduri, Nanda G; Iqbal, Anna

    2016-01-01

    POT). It has been shown that the gene encoding this transporter is upregulated during infection. NmPOT conformed to the typical chain length preference as observed in prototypical transporters of this family. In contrast to prototypical transporters, it was unable to accommodate a positively charged peptide...

  4. School Transportation Costs, Policies and Practices: A Review of Issues in New York and Selected States.

    Science.gov (United States)

    New York State Education Dept., Albany. Educational Research Services Unit.

    To draw comparisons for assessing transportation costs and developing recommendations for legislative action in New York, this study compares school transportation policies and practices that may be related to differences in transportation costs in eight states having the largest public school enrollments for 1980. Data were obtained from existing…

  5. Mode-selective vibrational modulation of charge transport in organic electronic devices

    KAUST Repository

    Bakulin, Artem A.; Lovrincic, Robert; Yu, Xi; Selig, Oleg; Bakker, Huib J.; Rezus, Yves L. A.; Nayak, Pabitra K.; Fonari, Alexandr; Coropceanu, Veaceslav; Bredas, Jean-Luc; Cahen, David

    2015-01-01

    The soft character of organic materials leads to strong coupling between molecular, nuclear and electronic dynamics. This coupling opens the way to influence charge transport in organic electronic devices by exciting molecular vibrational motions. However, despite encouraging theoretical predictions, experimental realization of such approach has remained elusive. Here we demonstrate experimentally that photoconductivity in a model organic optoelectronic device can be modulated by the selective excitation of molecular vibrations. Using an ultrafast infrared laser source to create a coherent superposition of vibrational motions in a pentacene/C60 photoresistor, we observe that excitation of certain modes in the 1,500–1,700 cm−1 region leads to photocurrent enhancement. Excited vibrations affect predominantly trapped carriers. The effect depends on the nature of the vibration and its mode-specific character can be well described by the vibrational modulation of intermolecular electronic couplings. This presents a new tool for studying electron–phonon coupling and charge dynamics in (bio)molecular materials.

  6. Mode-selective vibrational modulation of charge transport in organic electronic devices

    KAUST Repository

    Bakulin, Artem A.

    2015-08-06

    The soft character of organic materials leads to strong coupling between molecular, nuclear and electronic dynamics. This coupling opens the way to influence charge transport in organic electronic devices by exciting molecular vibrational motions. However, despite encouraging theoretical predictions, experimental realization of such approach has remained elusive. Here we demonstrate experimentally that photoconductivity in a model organic optoelectronic device can be modulated by the selective excitation of molecular vibrations. Using an ultrafast infrared laser source to create a coherent superposition of vibrational motions in a pentacene/C60 photoresistor, we observe that excitation of certain modes in the 1,500–1,700 cm−1 region leads to photocurrent enhancement. Excited vibrations affect predominantly trapped carriers. The effect depends on the nature of the vibration and its mode-specific character can be well described by the vibrational modulation of intermolecular electronic couplings. This presents a new tool for studying electron–phonon coupling and charge dynamics in (bio)molecular materials.

  7. Hepatitis C Virus Proteins Interact with the Endosomal Sorting Complex Required for Transport (ESCRT) Machinery via Ubiquitination To Facilitate Viral Envelopment.

    Science.gov (United States)

    Barouch-Bentov, Rina; Neveu, Gregory; Xiao, Fei; Beer, Melanie; Bekerman, Elena; Schor, Stanford; Campbell, Joseph; Boonyaratanakornkit, Jim; Lindenbach, Brett; Lu, Albert; Jacob, Yves; Einav, Shirit

    2016-11-01

    Enveloped viruses commonly utilize late-domain motifs, sometimes cooperatively with ubiquitin, to hijack the endosomal sorting complex required for transport (ESCRT) machinery for budding at the plasma membrane. However, the mechanisms underlying budding of viruses lacking defined late-domain motifs and budding into intracellular compartments are poorly characterized. Here, we map a network of hepatitis C virus (HCV) protein interactions with the ESCRT machinery using a mammalian-cell-based protein interaction screen and reveal nine novel interactions. We identify HRS (hepatocyte growth factor-regulated tyrosine kinase substrate), an ESCRT-0 complex component, as an important entry point for HCV into the ESCRT pathway and validate its interactions with the HCV nonstructural (NS) proteins NS2 and NS5A in HCV-infected cells. Infectivity assays indicate that HRS is an important factor for efficient HCV assembly. Specifically, by integrating capsid oligomerization assays, biophysical analysis of intracellular viral particles by continuous gradient centrifugations, proteolytic digestion protection, and RNase digestion protection assays, we show that HCV co-opts HRS to mediate a late assembly step, namely, envelopment. In the absence of defined late-domain motifs, K63-linked polyubiquitinated lysine residues in the HCV NS2 protein bind the HRS ubiquitin-interacting motif to facilitate assembly. Finally, ESCRT-III and VPS/VTA1 components are also recruited by HCV proteins to mediate assembly. These data uncover involvement of ESCRT proteins in intracellular budding of a virus lacking defined late-domain motifs and a novel mechanism by which HCV gains entry into the ESCRT network, with potential implications for other viruses. Viruses commonly bud at the plasma membrane by recruiting the host ESCRT machinery via conserved motifs termed late domains. The mechanism by which some viruses, such as HCV, bud intracellularly is, however, poorly characterized. Moreover, whether

  8. Transportation

    International Nuclear Information System (INIS)

    Anon.

    1998-01-01

    Here is the decree of the thirtieth of July 1998 relative to road transportation, to trade and brokerage of wastes. It requires to firms which carry out a road transportation as well as to traders and to brokers of wastes to declare their operations to the prefect. The declaration has to be renewed every five years. (O.M.)

  9. Analysis and selection of a system for hydraulic transport of slags in the Mironovskii power plant

    Energy Technology Data Exchange (ETDEWEB)

    Mirgorodskii, V.G.; Mova, M.E.; Korenev, V.E.; Grechikhin, Yu.A. (Donetskii Politekhnicheskii Institut (USSR))

    1991-01-01

    Discusses systems for hydraulic transport of ashes and slags from combustion of black coal (with an ash content of 40.5%) in the Mironovskii power plant. Three systems are comparatively evaluated: hydraulic transport under influence of gravity, hydraulic transport with a system of dredging pumps, or an airlift pump system. Design of each system, its operation and types of pumps or airlift systems are discussed. The evaluation concentrates on the hydraulic transport system with 1 to 3 airlift pumps each with a capacity ranging from 110 to 890 m{sup 3}/h. Optimum design of the airlift hydraulic system for slag and ash transport is described.

  10. Selective binding of 2-[{sup 125}I]iodo-nisoxetine to norepinephrine transporters in the brain

    Energy Technology Data Exchange (ETDEWEB)

    Kung, M.-P.; Choi, Seok-Rye; Hou, Catherine; Zhuang, Z.-P.; Foulon, Catherine; Kung, Hank F. E-mail: kunghf@sunmac.spect.upenn.edu

    2004-07-01

    A radioiodinated ligand, (R)-N-methyl-(2-[{sup 125}I]iodo-phenoxy)-3-phenylpropylamine, [{sup 125}I]2-INXT, targeting norepinephrine transporters (NET), was successfully prepared. A no-carrier-added product, [{sup 125}I]2-INXT, displayed a saturable binding with a high affinity (K{sub d}=0.06 nM) in the homogenates prepared from rat cortical tissues as well as from LLC-PK{sub 1} cells expressing NET. A relatively low number of binding sties (B{sub max}=55 fmol/mg protein) measured with [{sup 125}I]2-INXT in rat cortical homogenates is consistent with the value reported for a known NET ligand, [{sup 3}H]nisoxetine. Competition studies with various compounds on [{sup 125}I]2-INXT binding clearly confirmed the pharmacological specificity and selectivity for NET binding sites. Following a tail-vein injection of [{sup 125}I]2-INXT in rats, a good initial brain uptake was observed (0.56% dose at 2 min) followed by a slow washout from the brain (0.2% remained at 3 hours post-injection). The hypothalamus (a NET-rich region) to striatum (a region devoid of NET) ratio was 1.5 at 3 hours post-i.v. injection. Pretreatment of rats with nisoxetine significantly inhibited the uptake of [{sup 125}I]2-INXT (70-100% inhibition) in locus coeruleus, hypothalamus and raphe nuclei, regions known to have a high density of NET; whereas escitalopram, a serotonin transporter ligand, did not show a similar effect. Ex vivo autoradiography of rat brain sections of [{sup 125}I]2-INXT (at 3 hours after an i.v. injection) displayed an excellent regional brain localization pattern corroborated to the specific NET distribution in the brain. The specific brain localization was significantly reduced by a dose of nisoxetine pretreatment. Taken together, the data suggest that [{sup 123}I]2-INXT may be useful for mapping NET binding sites in the brain.

  11. Proposal of guidelines for selecting optimum options in packagings and transportation systems of spent fuel

    International Nuclear Information System (INIS)

    Saegusa, T.; Abe, H.; Fukuda, S.

    1983-01-01

    Type and size of spent fuel shipping packagings and packaging transport ships in spent fuel transport system would have been determined separately in response to technical requirements etc. of reactor sites and reprocessing plants. However, since more and more spent fuel will be generated from world's nuclear power plants and will be transported much frequently to reprocessing plants or storage facilities, the current spent fuel transport system will have to be necessarily reexamined from the operational and economical aspects or an optimum transport system may have to be newly determined in the near future. In the literature, a variety of options are found, particularly of spent fuel packagings. This paper listed and classified options of spent fuel packagings and packaging transport ships in the transportation systems of spent fuel on the basis of literature surveys. These options were discussed from viewpoints of designers and users and compared in terms of transport efficiency. Finally, one way to determine an optimum transport system of spent fuel was indicated considering the total transport system in the light of safety, operational efficiency and economy

  12. Transportation

    National Research Council Canada - National Science Library

    Allshouse, Michael; Armstrong, Frederick Henry; Burns, Stephen; Courts, Michael; Denn, Douglas; Fortunato, Paul; Gettings, Daniel; Hansen, David; Hoffman, D. W; Jones, Robert

    2007-01-01

    .... The ability of the global transportation industry to rapidly move passengers and products from one corner of the globe to another continues to amaze even those wise to the dynamics of such operations...

  13. Selective downregulation of mitochondrial electron transport chain activity and increased oxidative stress in human atrial fibrillation.

    Science.gov (United States)

    Emelyanova, Larisa; Ashary, Zain; Cosic, Milanka; Negmadjanov, Ulugbek; Ross, Gracious; Rizvi, Farhan; Olet, Susan; Kress, David; Sra, Jasbir; Tajik, A Jamil; Holmuhamedov, Ekhson L; Shi, Yang; Jahangir, Arshad

    2016-07-01

    Mitochondria are critical for maintaining normal cardiac function, and a deficit in mitochondrial energetics can lead to the development of the substrate that promotes atrial fibrillation (AF) and its progression. However, the link between mitochondrial dysfunction and AF in humans is still not fully defined. The aim of this study was to elucidate differences in the functional activity of mitochondrial oxidative phosphorylation (OXPHOS) complexes and oxidative stress in right atrial tissue from patients without (non-AF) and with AF (AF) who were undergoing open-heart surgery and were not significantly different for age, sex, major comorbidities, and medications. The overall functional activity of the electron transport chain (ETC), NADH:O2 oxidoreductase activity, was reduced by 30% in atrial tissue from AF compared with non-AF patients. This was predominantly due to a selective reduction in complex I (0.06 ± 0.007 vs. 0.09 ± 0.006 nmol·min(-1)·citrate synthase activity(-1), P = 0.02) and II (0.11 ± 0.012 vs. 0.16 ± 0.012 nmol·min(-1)·citrate synthase activity(-1), P = 0.003) functional activity in AF patients. Conversely, complex V activity was significantly increased in AF patients (0.21 ± 0.027 vs. 0.12 ± 0.01 nmol·min(-1)·citrate synthase activity(-1), P = 0.005). In addition, AF patients exhibited a higher oxidative stress with increased production of mitochondrial superoxide (73 ± 17 vs. 11 ± 2 arbitrary units, P = 0.03) and 4-hydroxynonenal level (77.64 ± 30.2 vs. 9.83 ± 2.83 ng·mg(-1) protein, P = 0.048). Our findings suggest that AF is associated with selective downregulation of ETC activity and increased oxidative stress that can contribute to the progression of the substrate for AF. Copyright © 2016 the American Physiological Society.

  14. Facilitation as a teaching strategy : experiences of facilitators

    Directory of Open Access Journals (Sweden)

    E Lekalakala-Mokgele

    2006-09-01

    Full Text Available Changes in nursing education involve the move from traditional teaching approaches that are teacher-centred to facilitation, a student centred approach. The studentcentred approach is based on a philosophy of teaching and learning that puts the learner on centre-stage. The aim of this study was to identify the challenges of facilitators of learning using facilitation as a teaching method and recommend strategies for their (facilitators development and support. A qualitative, explorative and contextual design was used. Four (4 universities in South Africa which utilize facilitation as a teaching/ learning process were identified and the facilitators were selected to be the sample of the study. The main question posed during in-depth group interviews was: How do you experience facilitation as a teaching/learning method?. Facilitators indicated different experiences and emotions when they first had to facilitate learning. All of them indicated that it was difficult to facilitate at the beginning as they were trained to lecture and that no format for facilitation was available. They experienced frustrations and anxieties as a result. The lack of knowledge of facilitation instilled fear in them. However they indicated that facilitation had many benefits for them and for the students. Amongst the ones mentioned were personal and professional growth. Challenges mentioned were the fear that they waste time and that they do not cover the content. It is therefore important that facilitation be included in the training of nurse educators.

  15. Transport of D-xylose in Lactobacillus pentosus, Lactobacillus casei, and Lactobacillus plantarum: Evidence for a mechanism of facilitated diffusion via the phosphoenolpyruvate:mannose phosphotransferase system

    NARCIS (Netherlands)

    Chaillou, S.; Pouwels, P.H.; Postma, P.W.

    1999-01-01

    We have identified and characterized the D-xylose transport system of Lactobacillus pentosus. Uptake of D-xylose was not driven by the proton motive force generated by malolactic fermentation and required D-xylose metabolism. The kinetics of D-xylose transport were indicative of a low- affinity

  16. Application of SELECT and SWAT models to simulate source load, fate, and transport of fecal bacteria in watersheds.

    Science.gov (United States)

    Ranatunga, T.

    2017-12-01

    Modeling of fate and transport of fecal bacteria in a watershed is a processed based approach that considers releases from manure, point sources, and septic systems. Overland transport with water and sediments, infiltration into soils, transport in the vadose zone and groundwater, die-off and growth processes, and in-stream transport are considered as the other major processes in bacteria simulation. This presentation will discuss a simulation of fecal indicator bacteria source loading and in-stream conditions of a non-tidal watershed (Cedar Bayou Watershed) in South Central Texas using two models; Spatially Explicit Load Enrichment Calculation Tool (SELECT) and Soil and Water Assessment Tool (SWAT). Furthermore, it will discuss a probable approach of bacteria source load reduction in order to meet the water quality standards in the streams. The selected watershed is listed as having levels of fecal indicator bacteria that posed a risk for contact recreation and wading by the Texas Commission of Environmental Quality (TCEQ). The SELECT modeling approach was used in estimating the bacteria source loading from land categories. Major bacteria sources considered were, failing septic systems, discharges from wastewater treatment facilities, excreta from livestock (Cattle, Horses, Sheep and Goat), excreta from Wildlife (Feral Hogs, and Deer), Pet waste (mainly from Dogs), and runoff from urban surfaces. The estimated source loads from SELECT model were input to the SWAT model, and simulate the bacteria transport through the land and in-stream. The calibrated SWAT model was then used to estimate the indicator bacteria in-stream concentrations for future years based on regional land use, population and household forecast (up to 2040). Based on the reductions required to meet the water quality standards in-stream, the corresponding required source load reductions were estimated.

  17. Facilitating Transfers

    DEFF Research Database (Denmark)

    Kjær, Poul F.

    to specific logics of temporalisation and spatial expansion of a diverse set of social processes in relation to, for example, the economy, politics, science and the mass media. On this background, the paper will more concretely develop a conceptual framework for classifying different contextual orders...... that the essential functional and normative purpose of regulatory governance is to facilitate, stabilise and justify the transfer of condensed social components (such as economic capital and products, political decisions, legal judgements, religious beliefs and scientific knowledge) from one social contexts...

  18. Influence of selected variables on transport of plutonium to spores of Aspergillus niger

    International Nuclear Information System (INIS)

    Au, F.H.F.; Beckert, W.F.

    1975-01-01

    Studies were carried out on the influences of different chemical forms and concentrations of Pu at two hydrogen ion concentrations of the culture medium on uptake and transport of 238 Pu to the spores of Aspergillus niger. Results indicated that Pu, when added to the culture medium as dioxide microspheres, nitrate, or citrate complex, was transported to the spores, and that an almost linear relationship existed between transport and concentration. Raising the pH of the culture medium from 2.5 to 5.5 generally increased transport of Pu to spores for all three chemical forms. At Pu concentrations of 224 pCi/g in the culture media, and for both pH 2.5 and 5.5, transport of Pu to spores was approximately three times as high from the nitrate or citrate form as from the dioxide microspheres. (auth)

  19. Color selective photodetector and methods of making

    Science.gov (United States)

    Walker, Brian J.; Dorn, August; Bulovic, Vladimir; Bawendi, Moungi G.

    2013-03-19

    A photoelectric device, such as a photodetector, can include a semiconductor nanowire electrostatically associated with a J-aggregate. The J-aggregate can facilitate absorption of a desired wavelength of light, and the semiconductor nanowire can facilitate charge transport. The color of light detected by the device can be chosen by selecting a J-aggregate with a corresponding peak absorption wavelength.

  20. Influence of Malfunctions of Selected Bus Subsystems on Bus Transportation Safety

    Directory of Open Access Journals (Sweden)

    Bojar Piotr

    2016-10-01

    Full Text Available This article introduces division of transport systems into land transport systems (road and rail as well as land and water transport systems (inland and sea, depending on the type of environment in which these systems carry out their tasks. Such systems comprise the class of social engineering systems of the Man – Technological Object – Environment (M – TO – E type. Such systems are influenced by forcing factors, leading to changes in their condition. Such factors may be divided into operational, external and anthropotechnical and they cause the degradation of the system on various levels, including a decrease of the degree of its safety. The article attempts to evaluate the safety of the operation of transport systems on the basis of the evaluation of the safety of the transport process carried out over a defined time interval Δt. The evaluation of the safety of the implemented transport process was prepared on the basis of a set of calculated index values determined depending on the type of transport.

  1. Motivation of Employees of Transport and Logistics Companies in the Czech Republic and in a Selected Region of the PRC

    Directory of Open Access Journals (Sweden)

    Ližbetinová Lenka

    2017-01-01

    Full Text Available Improvement of employee performance is an inseparable part of an enterprise. It ensures the fulfilment of goals and the company profitability. The main goal of the paper is to present the results of a research focused on comparison of the motivation factors of employees of transport and logistics companies in selected regions. The research carried out in 2017 examined the level of the motivation in the conditions of transport and logistics companies in the Czech Republic and the Peking Municipality in the PRC. These territories have different historic and cultural backgrounds, which leads to a high assumption of the existence of different views of the importance of motivation factors not only in the sphere of transport. The contribution also brings comparison of the preferences from the gender point of view.

  2. Effect of selective blockade of oxygen consumption, glucose transport, and Ca2+ influx on thyroxine action in human mononuclear cells

    DEFF Research Database (Denmark)

    Kvetny, J; Matzen, L E

    1990-01-01

    The effect of selective blockade of cellular glucose transporters, Ca2+ influx, and mitochondrial oxygen consumption on thyroxine (T4)-stimulated oxygen consumption and glucose uptake was examined in human mononuclear blood cells. Blockade of glucose transporters by cytochalasin B (1 x 10(-5) mol....../L) and of Ca2+ influx by alprenolol (1 x 10(-5) mol/L) and verapamil (4 x 10(-4) mol/L) inhibited T4-activated glucose uptaken and reduced T4-stimulated oxygen consumption by 20%. Uncoupling of mitochondrial oxygen consumption by azide (1 x 10(-3) mol/L) inhibited T4-stimulated oxygen consumption, but had...... no effect on glucose uptake. We conclude that T4-stimulated glucose uptake in human mononuclear blood cells is dependent on intact glucose transporters and Ca2+ influx, but not on mitochondrial oxygen consumption. However, oxygen consumption is, in part, dependent on intact glucose uptake....

  3. The Role of Subsurface Properties on Transport of Water and Trace Gases: 1D Simulations at Selected Mars Landing Sites.

    Science.gov (United States)

    Karatekin, O.; Gloesener, E.; Dehant, V. M. A.

    2017-12-01

    In this work, water ice stability and water vapour transport through porous martian subsurface are studied using a 1D diffusive model. The role of adsorption on water transfer in martian conditions is investigated as well as the range of parameters that have the largest effect on gas transport. In addition, adsorption kinetics is considered to examine its influence on the water vapor exchange between the subsurface and the atmosphere. As methane has been detected in the martian atmosphere, the subsurface model is then used to study methane diffusion in the CH4/CO2/H2O system from variable depths under the surface. The results of subsurface gas transport at selected locations/landing sites are shown and implications for present/future observations are discussed.

  4. Application of geographic information systems (GIS) for livability : case studies of select transportation agencies.

    Science.gov (United States)

    2011-03-01

    Livability is the idea that transportation, land use, housing, energy, and environmental considerations can be integrated to protect the environment, promote equitable development, and help to address the challenges of climate change. Geographi...

  5. Cyclodextrin Films with Fast Solvent Transport and Shape-Selective Permeability

    KAUST Repository

    Villalobos, Luis Francisco; Huang, Tiefan; Peinemann, Klaus-Viktor

    2017-01-01

    paths of defined aperture in the separation layer that can effectively discriminate between molecules. The transport of molecules through these membranes is highly shape-sensitive. In addition, the presence of hydrophobic (cavity) and hydrophilic (ester

  6. Facilitating participation

    DEFF Research Database (Denmark)

    Skøtt, Bo

    2018-01-01

    the resulting need for a redefinition of library competence. In doing this, I primarily address the first two questions from Chapter 1 and how they relate to the public’s informal, leisure-time activities in a networked society. In particular, I focus on the skills of reflexive self-perception and informed...... opinion formation. Further, I point out the significance which these informal leisure-time activities have for public library staff’s cultural dissemination skills. In this way, I take on the question of the skills required for facilitating the learning of a participatory public (cf. Chapter 1......), exemplifying with the competence required of library staff. My discussion will proceed by way of a literature review. In the next section, I shall explain how and what sources were chosen and section three and four present the theoretical framework and how the applied theories are related. In the fifth section...

  7. Facilitating Transfers

    DEFF Research Database (Denmark)

    Kjær, Poul F.

    2018-01-01

    Departing from the paradox that globalisation has implied an increase, rather than a decrease, in contextual diversity, this paper re-assesses the function, normative purpose and location of Regulatory Governance Frameworks in world society. Drawing on insights from sociology of law and world...... society studies, the argument advanced is that Regulatory Governance Frameworks are oriented towards facilitating transfers of condensed social components, such as economic capital and products, legal acts, political decisions and scientific knowledge, from one legally-constituted normative order, i.......e. contextual setting, to another. Against this background, it is suggested that Regulatory Governance Frameworks can be understood as schemes which act as ‘rites of passage’ aimed at providing legal stabilisation to social processes characterised by liminality, i.e ambiguity, hybridity and in-betweenness....

  8. Multi-component transport in polymers: hydrocarbon / hydrogen separation by reverse selectivity membrane; Transport multi-composants dans les polymeres: separation hydrocarbures / hydrogene par membrane a selectivite inverse

    Energy Technology Data Exchange (ETDEWEB)

    Mauviel, G.

    2003-12-15

    Hydrogen separation by reverse selectivity membranes is investigated. The first goal is to develop materials showing an increased selectivity. Silicone membranes loaded with inorganic fillers have been prepared, but the expected enhancement is not observed. The second goal is to model the multi- component transport through rubbers. Indeed the permeability model is not able to predict correctly permeation when a vapour is present. Thus many phenomena have to be considered: diffusional inter-dependency, sorption synergy, membrane swelling and drag effect. The dependence of diffusivities with the local composition is modelled according to free-volume theory. The model resolution allows to predict the permeation flow-rates of mixed species from their pure sorption and diffusion data. For the systems under consideration, the diffusional inter-dependency is shown to be preponderant. Besides, sorption synergy importance is pointed out, whereas it is most often neglected. (author)

  9. Tritium Suicide Selection Identifies Proteins Involved in the Uptake and Intracellular Transport of Sterols in Saccharomyces cerevisiae▿

    Science.gov (United States)

    Sullivan, David P.; Georgiev, Alexander; Menon, Anant K.

    2009-01-01

    Sterol transport between the plasma membrane (PM) and the endoplasmic reticulum (ER) occurs by a nonvesicular mechanism that is poorly understood. To identify proteins required for this process, we isolated Saccharomyces cerevisiae mutants with defects in sterol transport. We used Upc2-1 cells that have the ability to take up sterols under aerobic conditions and exploited the observation that intracellular accumulation of exogenously supplied [3H]cholesterol in the form of [3H]cholesteryl ester requires an intact PM-ER sterol transport pathway. Upc2-1 cells were mutagenized using a transposon library, incubated with [3H]cholesterol, and subjected to tritium suicide selection to isolate mutants with a decreased ability to accumulate [3H]cholesterol. Many of the mutants had defects in the expression and trafficking of Aus1 and Pdr11, PM-localized ABC transporters that are required for sterol uptake. Through characterization of one of the mutants, a new role was uncovered for the transcription factor Mot3 in controlling expression of Aus1 and Pdr11. A number of mutants had transposon insertions in the uncharacterized Ydr051c gene, which we now refer to as DET1 (decreased ergosterol transport). These mutants expressed Aus1 and Pdr11 normally but were severely defective in the ability to accumulate exogenously supplied cholesterol. The transport of newly synthesized sterols from the ER to the PM was also defective in det1Δ cells. These data indicate that the cytoplasmic protein encoded by DET1 is involved in intracellular sterol transport. PMID:19060182

  10. Transportation

    Science.gov (United States)

    2007-01-01

    Faculty ii INDUSTRY TRAVEL Domestic Assistant Deputy Under Secretary of Defense (Transportation Policy), Washington, DC Department of...developed between the railroad and trucking industries. Railroads: Today’s seven Class I freight railroad systems move 42% of the nation’s intercity ...has been successfully employed in London to reduce congestion and observed by this industry study during its travels . It is currently being

  11. Application of the newly developed 3D transport code r3t to selected field cases

    International Nuclear Information System (INIS)

    Rubel, A.; Fein, E.

    2006-01-01

    To model the transport of contaminants in connexion with long-term safety analyses of repositories for radioactive waste recently the numerical model r 3 t was developed. In the following first applications of r 3 t are presented. The results of modelling of the transport of zinc at the sewage treatment facility in Cape Cod, Massachusetts, and of trace elements in the frame work of the in-situ diffusion experiments DI-A and DR at the underground laboratory Mont Terri are shown. (authors)

  12. Electrodriven selective transport of Cs+ using chlorinated cobalt dicarbollide in polymer inclusion membrane: a novel approach for cesium removal from simulated nuclear waste solution.

    Science.gov (United States)

    Chaudhury, Sanhita; Bhattacharyya, Arunasis; Goswami, Asok

    2014-11-04

    The work describes a novel and cleaner approach of electrodriven selective transport of Cs from simulated nuclear waste solutions through cellulose tri acetate (CTA)/poly vinyl chloride (PVC) based polymer inclusion membrane. The electrodriven cation transport together with the use of highly Cs+ selective hexachlorinated derivative of cobalt bis dicarbollide, allows to achieve selective separation of Cs+ from high concentration of Na+ and other fission products in nuclear waste solutions. The transport selectivity has been studied using radiotracer technique as well as atomic emission spectroscopic technique. Transport studies using CTA based membrane have been carried out from neutral solution as well as 0.4 M HNO3, while that with PVC based membrane has been carried out from 3 M HNO3. High decontamination factor for Cs+ over Na+ has been obtained in all the cases. Experiment with simulated high level waste solution shows selective transport of Cs+ from most of other fission products also. Significantly fast Cs+ transport rate along with high selectivity is an interesting feature observed in this membrane. The current efficiency for Cs+ transport has been found to be ∼100%. The promising results show the possibility of using this kind of electrodriven membrane transport methods for nuclear waste treatment.

  13. EFA6 regulates selective polarised transport and axon regeneration from the axon initial segment

    Czech Academy of Sciences Publication Activity Database

    Eva, R.; Koseki, H.; Kanamarlapudi, V.; Fawcett, James

    2017-01-01

    Roč. 130, č. 21 (2017), s. 3663-3675 ISSN 0021-9533 Institutional support: RVO:68378041 Keywords : axon regeneration * axon transport * neuronal polarisation Subject RIV: FH - Neurology OBOR OECD: Neuroscience s (including psychophysiology Impact factor: 4.431, year: 2016

  14. PIP-II Injector Test’s Low Energy Beam Transport: Commissioning and Selected Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Shemyakin, A. [Fermilab; Alvarez, M. [Fermilab; Andrews, R. [Fermilab; Carneiro, J.-P. [Fermilab; Chen, A. [Fermilab; Hanna, B. [Fermilab; Prost, L. [Fermilab; Scarpine, V. [Fermilab; D' Arcy, R. [University Coll. London; Wiesner, C. [Goethe U., Frankfurt (main)

    2016-09-16

    The PIP2IT test accelerator is under construction at Fermilab. Its ion source and Low Energy Beam Transport (LEBT) in its initial (straight) configuration have been commissioned to full specification parameters. This paper introduces the LEBT design and summarizes the outcome of the commissioning activities.

  15. Synthesis selective transport properties of cleft-type ionophores having two convergent hydroxamic acid functions

    International Nuclear Information System (INIS)

    Kim, Duck Hee; Choi, Mi Jung; Chang, Suk Kyu

    2001-01-01

    A series of cleft-type ionophores having two convergent hydroxamic acid functions are prepared and their selective ionophoric properties toward heavy metal and transition metal ions have been investigated. Hydroxamic acids 3 exhibited a prominent selectivity toward heavy metal ions of Hg 2+ and Pb 2+ , and transition metal ions of Cu 2+ over other transition metal and alkaline earth metal ions from slightly acidic source phase (pH 6) to an acidic receiving phase (pH 1). Selective ionophoric properties toward Pb 2+ and Cu 2+ ions over other surveyed metal ions are also confirmed by the FAB-MS measurements

  16. RoadRail: An economically viable infrastructure which facilitates the transition from oil to electricity for all forms of road transport

    DEFF Research Database (Denmark)

    Connolly, David

    2012-01-01

    to convert road transport from oil to electricity. This involves the electrification of major roads so that electric cars, vans, busses, and trucks can use electricity as their primary fuel over long distance, which in this study is referred to as ‘RoadRail’. This is a new and radical alternative......In recent decades, economic renewable energy technologies have been developed for the electricity and heat sectors. Although there has been some development in the transport sector, there is still no well-establish sustainable alternatives to oil. In this study, a new alternative is proposed...... and electricity/oil costs, Denmark is presented as a case study for the installation of RoadRail. The results indicate that based on 2020 cost assumptions, RoadRail is a more socio-economic alternative than a business-as-usual using oil. This is primarily due to decreasing electric vehicle costs, decreasing...

  17. Safety Standard for Hydrogen and Hydrogen Systems: Guidelines for Hydrogen System Design, Materials Selection, Operations, Storage and Transportation. Revision

    Science.gov (United States)

    1997-01-01

    The NASA Safety Standard, which establishes a uniform process for hydrogen system design, materials selection, operation, storage, and transportation, is presented. The guidelines include suggestions for safely storing, handling, and using hydrogen in gaseous (GH2), liquid (LH2), or slush (SLH2) form whether used as a propellant or non-propellant. The handbook contains 9 chapters detailing properties and hazards, facility design, design of components, materials compatibility, detection, and transportation. Chapter 10 serves as a reference and the appendices contained therein include: assessment examples; scaling laws, explosions, blast effects, and fragmentation; codes, standards, and NASA directives; and relief devices along with a list of tables and figures, abbreviations, a glossary and an index for ease of use. The intent of the handbook is to provide enough information that it can be used alone, but at the same time, reference data sources that can provide much more detail if required.

  18. The selection of a mode of urban transportation: Integrating psychological variables to discrete choice models

    International Nuclear Information System (INIS)

    Cordoba Maquilon, Jorge E; Gonzalez Calderon, Carlos A; Posada Henao, John J

    2011-01-01

    A study using revealed preference surveys and psychological tests was conducted. Key psychological variables of behavior involved in the choice of transportation mode in a population sample of the Metropolitan Area of the Valle de Aburra were detected. The experiment used the random utility theory for discrete choice models and reasoned action in order to assess beliefs. This was used as a tool for analysis of the psychological variables using the sixteen personality factor questionnaire (16PF test). In addition to the revealed preference surveys, two other surveys were carried out: one with socio-economic characteristics and the other with latent indicators. This methodology allows for an integration of discrete choice models and latent variables. The integration makes the model operational and quantifies the unobservable psychological variables. The most relevant result obtained was that anxiety affects the choice of urban transportation mode and shows that physiological alterations, as well as problems in perception and beliefs, can affect the decision-making process.

  19. Selection of exception limits for all actinide nuclides based on revised criteria for safe international transport

    International Nuclear Information System (INIS)

    Lavarenne, C.; Rouyer, V.; Sert, G.; Mennerdahl, D.; Dean, C.; Barton, N.; Jean, F.

    2003-01-01

    Since 1998, there have been some speculations about future transport of significant quantities and concentrations of other actinide nuclides than the four currently listed in the regulation for the safe transport of the radioactive material. Therefore, it raised a need to specify exception limits for such actinides. Additionally, the total fissile nuclide mass per consignment of excepted packages was limited in the 1996 edition of the regulations (a conveyance limit is preliminary supported in the 2003 revision). The proposed changes of the rules have to take this new control into account. The European Community (DGTREN) decided to fund a project related to this subject. In order to define credible exception limits, it was necessary to have reasonably accurate data for all actinide nuclides. Then the authors of the study decided to perform calculations with different codes (MONK, MCNP, CRISTAL, SCALE) and different cross-section libraries (JEF2.2, ENDFB, JENDL, etc.). This article presents the work achieved and gives propositions of modification for the IAEA requirements for the Safe Transport of Radioactive Material related to, firstly, the list of the fissile materials, and secondly, the rule to determine the quantities of actinide nuclides that can be excepted from the requirements for the packages containing fissile materials. The participants acknowledge the DGTREN who made this work possible due to its support. (author)

  20. A dispersion model of transport media in radiotracer investigations on selected chemical installations

    International Nuclear Information System (INIS)

    Iller, E.

    1999-01-01

    Tracer investigations of media transport through chemical reactors play a significant role in the chemical technology. They provide the basis for the determination of some important process parameters, such as flow character of the transported medium, degree of utilisation of the reactor volume during chemical transitions of substrates or even indicate possible mechanisms of chemical reactions. Determination of the medium flow characteristics is closely connected with the mathematical description of the process - a mathematical model of transport. The method of assessment of radiotracers suitability for the investigation of distillation processes presented in this paper allows to determine, in a simple manner, the parameters of distillation characteristics of the radionuclides, the average distillation temperature, the range of distillation temperatures, a suitable radiochemical purity. These parameters precisely determine the behavior of tracers to be expected in a wide range of variable conditions of the distillation process. Applications of tracer tested in such a manner to the investigations of dynamics of media in the industrial rectification columns has resulted in obtaining a dependable evaluation of the performance of these columns in a wide range of changes of their operational parameters. Particular attention has been paid to dynamics of the liquid [phase on the column plate. A dispersion model of liquid flow with hold-up zones has been proposed for the description of the liquid phase transport in the plate - overall assembly.The model consists of a number of flow and stagnant zones, with mass transfer between them. Another example of practical application of results from radiotracer investigation is an analysis of of phase dynamics in the installations designed for the process of liquefaction of Polish coals by means of their catalytic hydrogenation. For the analysis of phase transport in a reaction vessel various mathematical models were applied with

  1. Spin and tunneling dynamics in an asymmetrical double quantum dot with spin-orbit coupling: Selective spin transport device

    Science.gov (United States)

    Singh, Madhav K.; Jha, Pradeep K.; Bhattacherjee, Aranya B.

    2017-09-01

    In this article, we study the spin and tunneling dynamics as a function of magnetic field in a one-dimensional GaAs double quantum dot with both the Dresselhaus and Rashba spin-orbit coupling. In particular, we consider different spatial widths for the spin-up and spin-down electronic states. We find that the spin dynamics is a superposition of slow as well as fast Rabi oscillations. It is found that the Rashba interaction strength as well as the external magnetic field strongly modifies the slow Rabi oscillations which is particularly useful for implementing solid state selective spin transport device.

  2. Innovation of the Process of Inventorying of the Selected Transport Units: Case Study in the Automotive Industry

    Directory of Open Access Journals (Sweden)

    Chocholáč Jan

    2017-05-01

    Full Text Available In the current situation, highly competitive time when the emphasis is on shortening delivery schedules, streamlining the production cycle and, ultimately, reducing the total cost businesses are forced to optimizations and innovations. The article deals with the inventory of the selected transport units in warehouses. The inventory is currently being carried out through manual labor of employees. This paper proposes a possible implementation of new and innovative approach to inventory control, with the help of an automated inventory realized by the drones.

  3. Cyclodextrin Films with Fast Solvent Transport and Shape-Selective Permeability

    KAUST Repository

    Villalobos, Luis Francisco

    2017-04-24

    This study describes the molecular-level design of a new type of filtration membrane made of crosslinked cyclodextrins-inexpensive macrocycles of glucose, shaped like hollow truncated cones. The channel-like cavities of cyclodextrins spawn numerous paths of defined aperture in the separation layer that can effectively discriminate between molecules. The transport of molecules through these membranes is highly shape-sensitive. In addition, the presence of hydrophobic (cavity) and hydrophilic (ester-crosslinked outer part) domains in these films results in high permeances for both polar and nonpolar solvents.

  4. Antioxidant defense in quiescent cells determines selectivity of electron transport chain inhibition-induced cell death

    Czech Academy of Sciences Publication Activity Database

    Blecha, Jan; Novais, Silvia Magalhaes; Rohlenová, Kateřina; Novotná, Eliška; Lettlová, Sandra; Schmitt, S.; Zischka, H.; Neužil, Jiří; Rohlena, Jakub

    2017-01-01

    Roč. 112, NOV 2017 (2017), s. 253-266 ISSN 0891-5849 R&D Projects: GA ČR GA16-22823S; GA ČR GA17-20904S; GA ČR GA16-12719S; GA MZd(CZ) NV16-31604A; GA MŠk(CZ) LM2015062; GA MŠk(CZ) LQ1604; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:86652036 Keywords : Electron transport chain * Supercomplexes * Antioxidant defense * SOD2 Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 5.606, year: 2016

  5. Thiamine supplementation facilitates thiamine transporter expression in the rumen epithelium and attenuates high-grain-induced inflammation in low-yielding dairy cows.

    Science.gov (United States)

    Pan, X H; Yang, L; Beckers, Y; Xue, F G; Tang, Z W; Jiang, L S; Xiong, B H

    2017-07-01

    An experiment was conducted to uncover the effects of increasing dietary grain levels on expression of thiamine transporters in ruminal epithelium, and to assess the protective effects of thiamine against high-grain-induced inflammation in dairy cows. Six rumen-fistulated, lactating Holstein dairy cows (627 ± 16.9 kg of body weight, 180 ± 6 d in milk; mean ± standard deviation) were randomly assigned to a replicated 3 × 3 Latin square design trial. Three treatments were control (20% dietary starch, dry matter basis), high-grain diet (HG, 33.2% dietary starch, DM basis), and HG diet supplemented with 180 mg of thiamine/kg of dry matter intake. On d 19 and 20 of each period, milk performance was measured. On d 21, ruminal pH, endotoxic lipopolysaccharide (LPS), and thiamine contents in rumen and blood, and plasma inflammatory cytokines were detected; a rumen papillae biopsy was taken on d 21 to determine the gene and protein expression of toll-like receptor 4 (TLR4) signaling pathways. The HG diet decreased ruminal pH (5.93 vs. 6.49), increased milk yield from 17.9 to 20.2 kg/d, and lowered milk fat and protein from 4.28 to 3.83%, and from 3.38 to 3.11%, respectively. The HG feeding reduced thiamine content in rumen (2.89 vs. 8.97 μg/L) and blood (11.66 vs. 17.63 μg/L), and the relative expression value of thiamine transporter-2 (0.37-fold) and mitochondrial thiamine pyrophosphate transporter (0.33-fold) was downregulated by HG feeding. The HG-fed cows exhibited higher endotoxin LPS in rumen fluid (134,380 vs. 11,815 endotoxin units/mL), and higher plasma concentrations of lipopolysaccharide binding protein and pro-inflammatory cytokines when compared with the control group. The gene and protein expression of tumor necrosis factor α (TNFα), IL1B, and IL6 in rumen epithelium increased when cows were fed the HG diet, indicating that local inflammation occurred. The depressions in ruminal pH, milk fat, and protein of HG-fed cows were reversed by thiamine

  6. Recommendations for computer code selection of a flow and transport code to be used in undisturbed vadose zone calculations for TWRS immobilized wastes environmental analyses

    International Nuclear Information System (INIS)

    VOOGD, J.A.

    1999-01-01

    An analysis of three software proposals is performed to recommend a computer code for immobilized low activity waste flow and transport modeling. The document uses criteria restablished in HNF-1839, ''Computer Code Selection Criteria for Flow and Transport Codes to be Used in Undisturbed Vadose Zone Calculation for TWRS Environmental Analyses'' as the basis for this analysis

  7. Structure-activity relationships for serotonin transporter and dopamine receptor selectivity.

    Science.gov (United States)

    Agatonovic-Kustrin, Snezana; Davies, Paul; Turner, Joseph V

    2009-05-01

    Antipsychotic medications have a diverse pharmacology with affinity for serotonergic, dopaminergic, adrenergic, histaminergic and cholinergic receptors. Their clinical use now also includes the treatment of mood disorders, thought to be mediated by serotonergic receptor activity. The aim of our study was to characterise the molecular properties of antipsychotic agents, and to develop a model that would indicate molecular specificity for the dopamine (D(2)) receptor and the serotonin (5-HT) transporter. Back-propagation artificial neural networks (ANNs) were trained on a dataset of 47 ligands categorically assigned antidepressant or antipsychotic utility. The structure of each compound was encoded with 63 calculated molecular descriptors. ANN parameters including hidden neurons and input descriptors were optimised based on sensitivity analyses, with optimum models containing between four and 14 descriptors. Predicted binding preferences were in excellent agreement with clinical antipsychotic or antidepressant utility. Validated models were further tested by use of an external prediction set of five drugs with unknown mechanism of action. The SAR models developed revealed the importance of simple molecular characteristics for differential binding to the D(2) receptor and the 5-HT transporter. These included molecular size and shape, solubility parameters, hydrogen donating potential, electrostatic parameters, stereochemistry and presence of nitrogen. The developed models and techniques employed are expected to be useful in the rational design of future therapeutic agents.

  8. ANALYSIS OF POTENTIAL INTENSITY OF SEDIMENT TRANSPORT ON SELECTED REACH OF THE NER RIVER

    Directory of Open Access Journals (Sweden)

    Ewelina Szałkiewicz

    2015-11-01

    Full Text Available The aim of this study was to perform a simulation of sediment transport for the section of the river Ner, while also utilizing GIS tools. Using the ArcGIS numerical model of channel and stream valleys were developed, and motion simulations and sediment transport set for 5 ten-year periods were performed in HEC-RAS. Updated geometries after the simulations were created using the tools of RAS Mapper. ArcGIS was used again for analysing the results. It was used to generate ordinates of bottom in the initial state and final. The difference between them illustrated the magnitude of erosion and accumulation. The process of erosion occurred in 13 sections of the analysed model (the standard differential ordinates negative, while the accumulation in 53 sections. The maximum value of shallowing bottom was 1.24 m (cross-section at km 18 + 868, while the largest deepening occurred at km 8 + 654 (– 0.76 m. All values, using ArcGIS, were marked on othophotomap.

  9. Aging Selectively Modulates Vitamin C Transporter Expression Patterns in the Kidney.

    Science.gov (United States)

    Forman, Katherine; Martínez, Fernando; Cifuentes, Manuel; Bertinat, Romina; Salazar, Katterine; Nualart, Francisco

    2017-09-01

    In the kidney, vitamin C is reabsorbed from the glomerular ultrafiltrate by sodium-vitamin C cotransporter isoform 1 (SVCT1) located in the brush border membrane of the proximal tubules. Although we know that vitamin C levels decrease with age, the adaptive physiological mechanisms used by the kidney for vitamin C reabsorption during aging remain unknown. In this study, we used an animal model of accelerated senescence (SAMP8 mice) to define the morphological alterations and aging-induced changes in the expression of vitamin C transporters in renal tissue. Aging induced significant morphological changes, such as periglomerular lymphocytic infiltrate and glomerular congestion, in the kidneys of SAMP8 mice, although no increase in collagen deposits was observed using 2-photon microscopy analysis and second harmonic generation. The most characteristic histological alteration was the dilation of intracellular spaces in the basolateral region of proximal tubule epithelial cells. Furthermore, a combination of laser microdissection, qRT-PCR, and immunohistochemical analyses allowed us to determine that SVCT1 expression specifically increased in the proximal tubules from the outer strip of the outer medulla (segment S3) and cortex (segment S2) during aging and that these tubules also express GLUT1. We conclude that aging modulates vitamin C transporter expression and that renal over-expression of SVCT1 enhances vitamin C reabsorption in aged animals that may synthesize less vitamin C. J. Cell. Physiol. 232: 2418-2426, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  10. Molecular interaction of selected phytochemicals under the charged environment of Plasmodium falciparum chloroquine resistance transporter (PfCRT) model.

    Science.gov (United States)

    Patel, Saumya K; Khedkar, Vijay M; Jha, Prakash C; Jasrai, Yogesh T; Pandya, Himanshu A; George, Linz-Buoy; Highland, Hyacinth N; Skelton, Adam A

    2016-01-01

    Phytochemicals of Catharanthus roseus Linn. and Tylophora indica have been known for their inhibition of malarial parasite, Plasmodium falciparum in cell culture. Resistance to chloroquine (CQ), a widely used antimalarial drug, is due to the CQ resistance transporter (CRT) system. The present study deals with computational modeling of Plasmodium falciparum chloroquine resistance transporter (PfCRT) protein and development of charged environment to mimic a condition of resistance. The model of PfCRT was developed using Protein homology/analogy engine (PHYRE ver 0.2) and was validated based on the results obtained using PSI-PRED. Subsequently, molecular interactions of selected phytochemicals extracted from C. roseus Linn. and T. indica were studied using multiple-iterated genetic algorithm-based docking protocol in order to investigate the translocation of these legends across the PfCRT protein. Further, molecular dynamics studies exhibiting interaction energy estimates of these compounds within the active site of the protein showed that compounds are more selective toward PfCRT. Clusters of conformations with the free energy of binding were estimated which clearly demonstrated the potential channel and by this means the translocation across the PfCRT is anticipated.

  11. Photosynthetic Entrainment of the Circadian Clock Facilitates Plant Growth under Environmental Fluctuations: Perspectives from an Integrated Model of Phase Oscillator and Phloem Transportation

    Directory of Open Access Journals (Sweden)

    Takayuki Ohara

    2017-10-01

    Full Text Available Plants need to avoid carbon starvation and resultant growth inhibition under fluctuating light environments to ensure optimal growth and reproduction. As diel patterns of carbon metabolism are influenced by the circadian clock, appropriate regulation of the clock is essential for plants to properly manage their carbon resources. For proper adjustment of the circadian phase, higher plants utilize environmental signals such as light or temperature and metabolic signals such as photosynthetic products; the importance of the latter as phase regulators has been recently elucidated. A mutant of Arabidopsis thaliana that is deficient in phase response to sugar has been shown, under fluctuating light conditions, to be unable to adjust starch turnover and to realize carbon homeostasis. Whereas, the effects of light entrainment on growth and survival of higher plants are well studied, the impact of phase regulation by sugar remains unknown. Here we show that endogenous sugar entrainment facilitates plant growth. We integrated two mathematical models, one describing the dynamics of carbon metabolism in A. thaliana source leaves and the other growth of sink tissues dependent on sucrose translocation from the source. The integrated model predicted that sugar-sensitive plants grow faster than sugar-insensitive plants under constant as well as changing photoperiod conditions. We found that sugar entrainment enables efficient carbon investment for growth by stabilizing sucrose supply to sink tissues. Our results highlight the importance of clock entrainment by both exogenous and endogenous signals for optimizing growth and increasing fitness.

  12. THE MATHEMATICAL MODEL OF SELECTING THE ROLLING STOCK FOR PASSENGER BUS TRANSPORTATION

    Directory of Open Access Journals (Sweden)

    M. Kostikova

    2017-06-01

    Full Text Available The problem of choosing buses of different carrying capacity while simultaneously using them on regular urban routes is considered. The indicators that affect the selection of the rolling stock are analyzed. Methods for constructing models, which allow calculating the number of buses of different classes for one city route are proposed. The implementation of the constructed models will make it possible to obtain the savings in capital expenditures, as well as reduce the operational costs of an enterprise.

  13. CO{sub 2} emissions from road transport and selected parts in the Kosice city

    Energy Technology Data Exchange (ETDEWEB)

    Carach, V.; Mueller, G.; Janoskova, K.

    2007-07-01

    At present, climatic changes are the most important and urgent worldwide problems. They are a real and rising threat to the environment. An intensive climatic research and monitoring yielded a better knowledge about the reasons and effects of global warming. Global warming in the range of 1.4 to 5.8 {sup o}C affects weather, year seasons, ecosystems, water sources, health of citizens, as well as global and domestic economy. Nowadays, it is clear that the climatic instability is mostly caused by human activities. 21% of total carbon dioxide (CO{sub 2}) emissions in Europe comes from traffic, which is one of the biggest sources of greenhouse effect gases and rises up to 2.5% every year. A main reason is the increasing automobile and airplane transport.

  14. Variability in dose estimates associated with the food-chain transport and ingestion of selected radionuclides

    International Nuclear Information System (INIS)

    Hoffman, F.O.; Gardner, R.H.; Eckerman, K.F.

    1982-06-01

    Dose predictions for the ingestion of 90 Sr and 137 Cs, using aquatic and terrestrial food chain transport models similar to those in the Nuclear Regulatory Commission's Regulatory Guide 1.109, are evaluated through estimating the variability of model parameters and determining the effect of this variability on model output. The variability in the predicted dose equivalent is determined using analytical and numerical procedures. In addition, a detailed discussion is included on 90 Sr dosimetry. The overall estimates of uncertainty are most relevant to conditions where site-specific data is unavailable and when model structure and parameter estimates are unbiased. Based on the comparisons performed in this report, it is concluded that the use of the generic default parameters in Regulatory Guide 1.109 will usually produce conservative dose estimates that exceed the 90th percentile of the predicted distribution of dose equivalents. An exception is the meat pathway for 137 Cs, in which use of generic default values results in a dose estimate at the 24th percentile. Among the terrestrial pathways of exposure, the non-leafy vegetable pathway is the most important for 90 Sr. For 90 Sr, the parameters for soil retention, soil-to-plant transfer, and internal dosimetry contribute most significantly to the variability in the predicted dose for the combined exposure to all terrestrial pathways. For 137 Cs, the meat transfer coefficient the mass interception factor for pasture forage, and the ingestion dose factor are the most important parameters. The freshwater finfish bioaccumulation factor is the most important parameter for the dose prediction of 90 Sr and 137 Cs transported over the water-fish-man pathway

  15. A Select Subset of Electron Transport Chain Genes Associated with Optic Atrophy Link Mitochondria to Axon Regeneration in Caenorhabditis elegans.

    Science.gov (United States)

    Knowlton, Wendy M; Hubert, Thomas; Wu, Zilu; Chisholm, Andrew D; Jin, Yishi

    2017-01-01

    The role of mitochondria within injured neurons is an area of active interest since these organelles are vital for the production of cellular energy in the form of ATP. Using mechanosensory neurons of the nematode Caenorhabditis elegans to test regeneration after neuronal injury in vivo , we surveyed genes related to mitochondrial function for effects on axon regrowth after laser axotomy. Genes involved in mitochondrial transport, calcium uptake, mitophagy, or fission and fusion were largely dispensable for axon regrowth, with the exception of eat-3/Opa1 . Surprisingly, many genes encoding components of the electron transport chain were dispensable for regrowth, except for the iron-sulfur proteins gas-1, nduf-2.2, nduf-7 , and isp-1 , and the putative oxidoreductase rad-8 . In these mutants, axonal development was essentially normal and axons responded normally to injury by forming regenerative growth cones, but were impaired in subsequent axon extension. Overexpression of nduf-2.2 or isp-1 was sufficient to enhance regrowth, suggesting that mitochondrial function is rate-limiting in axon regeneration. Moreover, loss of function in isp-1 reduced the enhanced regeneration caused by either a gain-of-function mutation in the calcium channel EGL-19 or overexpression of the MAP kinase DLK-1. While the cellular function of RAD-8 remains unclear, our genetic analyses place rad-8 in the same pathway as other electron transport genes in axon regeneration. Unexpectedly, rad-8 regrowth defects were suppressed by altered function in the ubiquinone biosynthesis gene clk-1 . Furthermore, we found that inhibition of the mitochondrial unfolded protein response via deletion of atfs-1 suppressed the defective regrowth in nduf-2.2 mutants. Together, our data indicate that while axon regeneration is not significantly affected by general dysfunction of cellular respiration, it is sensitive to the proper functioning of a select subset of electron transport chain genes, or to the

  16. The transport kinetics and selectivity of HpUreI, the urea channel from Helicobacter pylori†

    Science.gov (United States)

    Gray, Lawrence R; Gu, Sean X; Quick, Matthias; Khademi, Shahram

    2017-01-01

    Helicobacter pylori’s unique ability to colonize and survive in the acidic environment of the stomach is critically dependent on uptake of urea through the urea channel, HpUreI. Hence, HpUreI may represent a promising target for the development of specific drugs against this human pathogen. To obtain insight into the structure/function relationship of this channel, we have developed conditions for the high-yield expression and purification of stable recombinant HpUreI that allowed its detailed kinetic characterization in solubilized form and reconstituted into liposomes. Detergent-solubilized HpUreI forms homo-trimer, as determined by chemical cross-linking. Urea dissociation kinetics of purified HpUreI were determined by means of the scintillation proximity assay (SPA), whereas urea efflux was measured in HpUreI-containing proteoliposomes using stopped-flow spectrometry to determine the kinetics and selectivity of the urea channel. The kinetic analyses revealed that urea conduction in HpUreI is pH sensitive and saturable with a half-saturation concentration (or K0.5) of ~163 mM. Binding of urea by HpUreI was increased at lower pH; however, the apparent affinity of urea binding (~150 mM) was not significantly pH dependent. The solute selectivity analysis indicated that HpUreI is highly selective for urea and hydroxyurea. Removing either amino group of urea molecules diminishes their permeability through HpUreI. Similar to urea conduction, water diffusion through HpUreI is pH-dependent with low water permeability at neutral pH. PMID:21877689

  17. An Efficient approach for selective collection made by scavengers for transportation logistics of recyclable materials

    Directory of Open Access Journals (Sweden)

    Adelino Carlos Maccarini

    2014-01-01

    Full Text Available The advance of technology, associated to the increase in the production of recyclable waste due to the increase of consumption and population, has been led to a search for alternatives of management and minimization of this waste. A part of this recyclable material is collected by scavengers, who do it to guarantee their livelihood. Many of them face logistical difficulties in transportation, mainly when they have to walk long distances and the streets have high slopes. Therefore, to minimize these efforts, the purpose of this paper is to settle mobile warehouses to receive recyclable items, with trucks that receive in bulk all materials collected by the collectors, who will deliver them to someone who will be in the truck for weighing and subsequent payment to the collector. With the help of the Analysis of Variance – ANOVA, studies were made so that this receipt is a quick operation, with the historical record of each sampling in a spreadsheet and value calculations based on this description, thus minimizing errors in weighing in bulk and improving, in every collection, the system reliability.

  18. Monitoring of event-based mobilization of hydrophobic pollutants in rivers: calibration of turbidity as a proxy for particle facilitated transport in field and laboratory.

    Science.gov (United States)

    Rügner, Hermann; Schwientek, Marc; Egner, Marius; Grathwohl, Peter

    2014-08-15

    Transport of many pollutants in rivers is coupled to mobilization of suspended particles which typically occurs during floods. Since the amount of total suspended solids (TSS) in rivers can be monitored by turbidity measurements this may be used as a proxy for the total concentration of particle associated pollutants such as PAHs, PCBs, etc. and several heavy metals. Online turbidity measurements (e.g. by optical backscattering sensors) would then also allow for an assessment of particle and pollutant flux dynamics if once calibrated against TSS and total pollutant concentrations for a given catchment. In this study, distinct flood and thus turbidity events were sampled at high temporal resolution in three contrasting sub-catchments of the River Neckar in Southwest Germany (Ammer, Goldersbach, Steinlach) as well as in the River Neckar itself and investigated for the total amount of PAHs and TSS in water; turbidity (NTU) and grain size distributions of suspended solids were determined as well. Laboratory experiments were performed with natural river bed sediments from different locations (Ammer) to investigate PAH concentrations, TSS and turbidity during sedimentation of suspended particles under controlled conditions (yielding smaller and smaller suspended particles and TSS with time). Laboratory and field results agreed very well and showed that turbidity and TSS were linearly correlated over an extended turbidity range up to 2000 NTU for the field samples and up to 8000 NTU in lab experiments. This also holds for total PAH concentrations which can be reasonably well predicted based on turbidity measurements and TSS vs. PAHs relationships - even for high turbidity values observed during flood events (>2000 NTU). Total PAH concentrations on suspended solids were independent of grain size of suspended particles. This implies that for the rivers investigated the sorption capacity of particles did not change significantly during the observed events. Copyright © 2014

  19. 3D printing of an aortic aneurysm to facilitate decision making and device selection for endovascular aneurysm repair in complex neck anatomy.

    Science.gov (United States)

    Tam, Matthew D B S; Laycock, Stephen D; Brown, James R I; Jakeways, Matthew

    2013-12-01

    To describe rapid prototyping or 3-dimensional (3D) printing of aneurysms with complex neck anatomy to facilitate endovascular aneurysm repair (EVAR). A 75-year-old man had a 6.6-cm infrarenal aortic aneurysm that appeared on computed tomographic angiography to have a sharp neck angulation of ~90°. However, although the computed tomography (CT) data were analyzed using centerline of flow, the true neck length and relations of the ostial origins were difficult to determine. No multidisciplinary consensus could be reached as to which stent-graft to use owing to these borderline features of the neck anatomy. Based on past experience with rapid prototyping technology, a decision was taken to print a model of the aneurysm to aid in visualization of the neck anatomy. The CT data were segmented, processed, and converted into a stereolithographic format representing the lumen as a 3D volume, from which a full-sized replica was printed within 24 hours. The model demonstrated that the neck was adequate for stent-graft repair using the Aorfix device. Rapid prototyping of aortic aneurysms is feasible and can aid decision making and device delivery. Further work is required to test the value of 3D replicas in planning procedures and their impact on procedure time, radiation dose, and procedure cost.

  20. Selección de cadenas para equipos de transporte continuo. // Chain selection software for continuous conveyors.

    Directory of Open Access Journals (Sweden)

    F. Aguilar Parés

    2003-01-01

    ón, transportadores de tablillas, transportadores de rastrillos,elevadores de cangilones._____________________________________________________________________________Abstract:The design of conveyors and elevators that employ chains as driving member is commonly used in industry. An essentialelement for well functioning is the correct chain selection. There are a great variety of chains and attachments thataccomplish any requirements at manufacturers disposal. In order to supply these requirements there is a need to establish aprocedure that considers the following aspects:· Type of equipment (slat conveyor, flight conveyor, bucket conveyor, etc..· Transportation requirements (capacity, transportation velocity, material characteristics, etc..· Transportation conditions (overload, operation conditions, explotation time, etc..The resulting procedure is very annoying because there are stages in which a decision implies accommodation to latecalculations and as usual there is more than one solution. Therefore the SELCAD computation program is conceived for theuse by non experts in design and selection of continuous conveyors equipments. The program use data base from Link BeltIndustrial Chain Division catalog in which 14 types of chains are appraise with an average of 15 models for each and morethan 40 different attachments. Some of the program characteristics are:· User friendly environment (Visual Basic programation, version 5.· Help available at any moment.· Point out the characteristics of both driving member and gear.· Allows visualization of the selected real chain shape and attachment by photos.· Quick analysis of different variations.Key words: Transportation chain, slat conveyors, flight conveyor, bucket conveyor.

  1. A new structural class of subtype-selective inhibitor of cloned excitatory amino acid transporter, EAAT2

    DEFF Research Database (Denmark)

    Bräuner-Osborne, Hans; Hermit, M B; Nielsen, B

    2000-01-01

    We have studied the pharmacological effects of (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) and the enantiomers of (RS)-2-amino-3-(3-hydroxy-1,2, 5-thiadiazol-4-yl)propionic acid (TDPA) on cloned human excitatory amino acid transporter subtypes 1, 2 and 3 (EAAT1......-3) expressed in Cos-7 cells. Whereas AMPA and (R)-TDPA were both inactive as inhibitors of [3H]-(R)-aspartic acid uptake on all three EAAT subtypes, (S)-TDPA was shown to selectively inhibit uptake by EAAT2 with a potency equal to that of the endogenous ligand (S)-glutamic acid. (S)-TDPA thus represents a new...

  2. Ecological sustainability and personal behavior: relations demonstrated by the decision-making process of selecting a certain transportation mean

    Energy Technology Data Exchange (ETDEWEB)

    Priewasser, Reinhold [Linz Univ., Inst. for Environmental Management in Enterprises and Regions, Linz (Austria)

    1999-07-01

    Facing the aim of ecological sustainability only little emphasis has been placed on the fact that the extent of environmental stresses is not only a consequence of certain factual or structural conditions but also essentially determined by varying human behaviour patterns. Technologies and structures are not ecologically effective by themselves, their environmental relevance strongly depends on the persons' way of acting within the prevailing system. Recognising the importance of that perspective psychological and social theories about the generation of personal behaviour as well as the theoretical models of learning can offer useful indications concerning the interpersonal and extrapersonal preconditions of environmentally oriented acting. With reference to the decision-making process of selecting a certain transportation mean, the influences of rational and emotional factors and obstacles to an ecologically sustainable personal act should be exemplary demonstrated. At the same time very effective points of departure for behavioural change can be identified. (Author)

  3. A fast inverse treatment planning strategy facilitating optimized catheter selection in image-guided high-dose-rate interstitial gynecologic brachytherapy.

    Science.gov (United States)

    Guthier, Christian V; Damato, Antonio L; Hesser, Juergen W; Viswanathan, Akila N; Cormack, Robert A

    2017-12-01

    Interstitial high-dose rate (HDR) brachytherapy is an important therapeutic strategy for the treatment of locally advanced gynecologic (GYN) cancers. The outcome of this therapy is determined by the quality of dose distribution achieved. This paper focuses on a novel yet simple heuristic for catheter selection for GYN HDR brachytherapy and their comparison against state of the art optimization strategies. The proposed technique is intended to act as a decision-supporting tool to select a favorable needle configuration. The presented heuristic for catheter optimization is based on a shrinkage-type algorithm (SACO). It is compared against state of the art planning in a retrospective study of 20 patients who previously received image-guided interstitial HDR brachytherapy using a Syed Neblett template. From those plans, template orientation and position are estimated via a rigid registration of the template with the actual catheter trajectories. All potential straight trajectories intersecting the contoured clinical target volume (CTV) are considered for catheter optimization. Retrospectively generated plans and clinical plans are compared with respect to dosimetric performance and optimization time. All plans were generated with one single run of the optimizer lasting 0.6-97.4 s. Compared to manual optimization, SACO yields a statistically significant (P ≤ 0.05) improved target coverage while at the same time fulfilling all dosimetric constraints for organs at risk (OARs). Comparing inverse planning strategies, dosimetric evaluation for SACO and "hybrid inverse planning and optimization" (HIPO), as gold standard, shows no statistically significant difference (P > 0.05). However, SACO provides the potential to reduce the number of used catheters without compromising plan quality. The proposed heuristic for needle selection provides fast catheter selection with optimization times suited for intraoperative treatment planning. Compared to manual optimization, the

  4. Nanoengineered membranes for controlled transport

    Science.gov (United States)

    Doktycz, Mitchel J [Oak Ridge, TN; Simpson, Michael L [Knoxville, TN; McKnight, Timothy E [Greenback, TN; Melechko, Anatoli V [Oak Ridge, TN; Lowndes, Douglas H [Knoxville, TN; Guillorn, Michael A [Knoxville, TN; Merkulov, Vladimir I [Oak Ridge, TN

    2010-01-05

    A nanoengineered membrane for controlling material transport (e.g., molecular transport) is disclosed. The membrane includes a substrate, a cover definining a material transport channel between the substrate and the cover, and a plurality of fibers positioned in the channel and connected to an extending away from a surface of the substrate. The fibers are aligned perpendicular to the surface of the substrate, and have a width of 100 nanometers or less. The diffusion limits for material transport are controlled by the separation of the fibers. In one embodiment, chemical derivitization of carbon fibers may be undertaken to further affect the diffusion limits or affect selective permeability or facilitated transport. For example, a coating can be applied to at least a portion of the fibers. In another embodiment, individually addressable carbon nanofibers can be integrated with the membrane to provide an electrical driving force for material transport.

  5. Growth kinetics and mass transport mechanisms of GaN columns by selective area metal organic vapor phase epitaxy

    Science.gov (United States)

    Wang, Xue; Hartmann, Jana; Mandl, Martin; Sadat Mohajerani, Matin; Wehmann, Hergo-H.; Strassburg, Martin; Waag, Andreas

    2014-04-01

    Three-dimensional GaN columns recently have attracted a lot of attention as the potential basis for core-shell light emitting diodes for future solid state lighting. In this study, the fundamental insights into growth kinetics and mass transport mechanisms of N-polar GaN columns during selective area metal organic vapor phase epitaxy on patterned SiOx/sapphire templates are systematically investigated using various pitch of apertures, growth time, and silane flow. Species impingement fluxes on the top surface of columns Jtop and on their sidewall Jsw, as well as, the diffusion flux from the substrate Jsub contribute to the growth of the GaN columns. The vertical and lateral growth rates devoted by Jtop, Jsw and Jsub are estimated quantitatively. The diffusion length of species on the SiOx mask surface λsub as well as on the sidewall surfaces of the 3D columns λsw are determined. The influences of silane on the growth kinetics are discussed. A growth model is developed for this selective area metal organic vapor phase epitaxy processing.

  6. Evaluation of long-range transport potential of selected brominated flame retardants with measured 1-octanol-air partition coefficients

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun Jeong; Kwon, Jung Hwan [Div. of Environmental Science and Ecological Engineering, Korea University, Seoul (Korea, Republic of)

    2016-10-15

    Various alternative flame retardants are used in many countries since polybrominated diphenyl ethers (PBDEs) were classified as persistent organic pollutants (POPs). However, difficulties in the evaluation of the long-range transport potential (LRTP) of the alternatives are related to the lack of information on their physicochemical properties, which govern their environmental fates and transport. Based on the simulation of LRTP using OECD P{sub OV} and LRTP Screening Tool, five alternative brominated flame retardants (BFRs) (hexabromobenzene [HBB], 2,3,4,5,6-pentabromotoluene [PBT], 2,3,4,5,6-pentabromoethylbenzene [PBEB], 2-ethylhexyl 2,3,4,5-tetrabromobenzoate [TBB], and 1,2,4,5-tetrabromo-3,6-dimethylbenzene [TBX]), and 3 PBDEs (BDE-28, BDE-47, and BDE-99) were chosen to perform a refined assessment. This was done using an experimentally measured 1-octanol–air partition coefficient (K{sub OA}) for the calculation of the air–water partition coefficient (K{sub AW}) required for the model. The four selected alternative BFRs (HBB, PBT, PBEB, TBX) have K{sub OA} values close to the in silico estimation used in the screening evaluation. On the other hand, the measured K{sub OA} value for TBB was two orders of magnitude lower than the estimated value used in the screening simulation. The refined simulation showed that characteristic travel distance (CTD) and transfer efficiency (TE) for HBB, PBT, PBEB, and TBX were greater than those for BDE-28, whereas CTD and TE for TBB were lower than those for BDE-28. This suggested that TBB has a lower LRTP than BDE-28, considering the refined partition coefficients.

  7. Soil aggregate stability and size-selective sediment transport with surface runoff as affected by organic residue amendment.

    Science.gov (United States)

    Shi, Pu; Arter, Christian; Liu, Xingyu; Keller, Martin; Schulin, Rainer

    2017-12-31

    Aggregate breakdown influences the availability of soil particles for size-selective sediment transport with surface runoff during erosive rainfall events. Organic matter management is known to affect aggregate stability against breakdown, but little is known about how this translates into rainfall-induced aggregate fragmentation and sediment transport under field conditions. In this study, we performed field experiments in which artificial rainfall was applied after pre-wetting on three pairs of arable soil plots (1.5×0.75m) six weeks after incorporating a mixture of grass and wheat straw into the topsoil of one plot in each pair (OI treatment) but not on the other plot (NI treatment). Artificial rainfall was applied for approximately 2h on each pair at an intensity of 49.1mmh -1 . In both treatments, discharge and sediment concentration in the discharge were correlated and followed a similar temporal pattern after the onset of surface runoff: After a sharp increase at the beginning both approached a steady state. But the onset of runoff was more delayed on the OI plots, and the discharge and sediment concentration were in average only roughly half as high on the OI as on the NI plots. With increasing discharge the fraction of coarse sediment increased. This relationship did not differ between the two treatments. Thus, due to the lower discharge, the fraction of fine particles in the exported sediment was larger in the runoff from the OI plots than from the NI plots. The later runoff onset and lower discharge rate was related to a higher initial aggregate stability on the OI plots. Terrestrial laser scanning proved to be a very valuable method to map changes in the micro-topography of the soil surfaces. It revealed a much less profound decrease in surface roughness on the OI than on the NI plots. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Facilitated transport near the carrier saturation limit

    Directory of Open Access Journals (Sweden)

    Anawat Sungpet

    2002-11-01

    Full Text Available Permeation of ethylbenzene, styrene and 1-hexene through perfluorosulfonate ionomer membranes was carried out with the feed concentrations ranging from 1 M to pure. On comparison, fluxes of ethylbenzene through the Ag+-form membrane were the lowest. Only a small increase in ethylbenzene flux was observed after the feed concentration exceeded 3 M, indicating the existence of carrier saturation. The increase in styrene flux was suppressed to some degree at high concentration driving forces. In contrast, 1-hexene flux was the highest and continued to increase even at very high feed concentrations. After the experiments with pure feeds, extraction of the solutes from the membranes revealed that 62.5% of Ag+ ions reacted with 1-hexene as against 40.6% for styrene and 28.9% for ethylbenzene. Equilibrium constants, determined by distribution method, of 1-hexene, styrene and ethylbenzene were 129, 2.2 and 0.7 M-1 respectively, which suggested that stability of the complex was a key factor in the carrier saturation phenomenon.

  9. Protease-activated receptor-2 stimulates intestinal epithelial chloride transport through activation of PLC and selective PKC isoforms.

    Science.gov (United States)

    van der Merwe, Jacques Q; Moreau, France; MacNaughton, Wallace K

    2009-06-01

    Serine proteases play important physiological roles through their activity at G protein-coupled protease-activated receptors (PARs). We examined the roles that specific phospholipase (PL) C and protein kinase (PK) C (PKC) isoforms play in the regulation of PAR(2)-stimulated chloride secretion in intestinal epithelial cells. Confluent SCBN epithelial monolayers were grown on Snapwell supports and mounted in modified Ussing chambers. Short-circuit current (I(sc)) responses to basolateral application of the selective PAR(2) activating peptide, SLIGRL-NH(2), were monitored as a measure of net electrogenic ion transport caused by PAR(2) activation. SLIGRL-NH(2) induced a transient I(sc) response that was significantly reduced by inhibitors of PLC (U73122), phosphoinositol-PLC (ET-18), phosphatidylcholine-PLC (D609), and phosphatidylinositol 3-kinase (PI3K; LY294002). Immunoblot analysis revealed the phosphorylation of both PLCbeta and PLCgamma following PAR(2) activation. Pretreatment of the cells with inhibitors of PKC (GF 109203X), PKCalpha/betaI (Gö6976), and PKCdelta (rottlerin), but not PKCzeta (selective pseudosubstrate inhibitor), also attenuated this response. Cellular fractionation and immunoblot analysis, as well as confocal immunocytochemistry, revealed increases of PKCbetaI, PKCdelta, and PKCepsilon, but not PKCalpha or PKCzeta, in membrane fractions following PAR(2) activation. Pretreatment of the cells with U73122, ET-18, or D609 inhibited PKC activation. Inhibition of PI3K activity only prevented PKCdelta translocation. Immunoblots revealed that PAR(2) activation induced phosphorylation of both cRaf and ERK1/2 via PKCdelta. Inhibition of PKCbetaI and PI3K had only a partial effect on this response. We conclude that basolateral PAR(2)-induced chloride secretion involves activation of PKCbetaI and PKCdelta via a PLC-dependent mechanism resulting in the stimulation of cRaf and ERK1/2 signaling.

  10. Atomic density effects on temperature characteristics and thermal transport at grain boundaries through a proper bin size selection

    Energy Technology Data Exchange (ETDEWEB)

    Vo, Truong Quoc; Kim, BoHung, E-mail: muratbarisik@iyte.edu.tr, E-mail: bohungk@ulsan.ac.kr [School of Mechanical Engineering, University of Ulsan, Daehak-ro 93, Namgu, Ulsan 680-749 (Korea, Republic of); Barisik, Murat, E-mail: muratbarisik@iyte.edu.tr, E-mail: bohungk@ulsan.ac.kr [Department of Mechanical Engineering, Izmir Institute of Technology, Urla, Izmir 35430 (Turkey)

    2016-05-21

    This study focuses on the proper characterization of temperature profiles across grain boundaries (GBs) in order to calculate the correct interfacial thermal resistance (ITR) and reveal the influence of GB geometries onto thermal transport. The solid-solid interfaces resulting from the orientation difference between the (001), (011), and (111) copper surfaces were investigated. Temperature discontinuities were observed at the boundary of grains due to the phonon mismatch, phonon backscattering, and atomic forces between dissimilar structures at the GBs. We observed that the temperature decreases gradually in the GB area rather than a sharp drop at the interface. As a result, three distinct temperature gradients developed at the GB which were different than the one observed in the bulk solid. This behavior extends a couple molecular diameters into both sides of the interface where we defined a thickness at GB based on the measured temperature profiles for characterization. Results showed dependence on the selection of the bin size used to average the temperature data from the molecular dynamics system. The bin size on the order of the crystal layer spacing was found to present an accurate temperature profile through the GB. We further calculated the GB thickness of various cases by using potential energy (PE) distributions which showed agreement with direct measurements from the temperature profile and validated the proper binning. The variation of grain crystal orientation developed different molecular densities which were characterized by the average atomic surface density (ASD) definition. Our results revealed that the ASD is the primary factor affecting the structural disorders and heat transfer at the solid-solid interfaces. Using a system in which the planes are highly close-packed can enhance the probability of interactions and the degree of overlap between vibrational density of states (VDOS) of atoms forming at interfaces, leading to a reduced ITR. Thus, an

  11. Design of the prototype of a beam transport line for handling and selection of low energy laser-driven beams

    Energy Technology Data Exchange (ETDEWEB)

    Schillaci, F., E-mail: francesco.schillaci@eli-beams.eu [INFN-LNS, Catania (Italy); Maggiore, M. [INFN-LNL, Legnaro (Italy); Cirrone, G.A.P.; Cuttone, G.; Pisciotta, P.; Costa, M.; Rifuggiato, D.; Romano, F. [INFN-LNS, Catania (Italy); Scuderi, V. [INFN-LNS, Catania (Italy); Institute of Physics of the ASCR, ELI-Beamlines Project, Prague (Czech Republic)

    2016-11-21

    A first prototype of transport beam-line for laser-driven ion beams to be used for the handling of particles accelerated by high-power laser interacting with solid targets has been realized at INFN. The goal is the production of a controlled and stable beam in terms of energy and angular spread. The beam-line consists of two elements: an Energy Selection System (ESS), already realized and characterized with both conventional and laser-accelerated beams, and a Permanent Magnet Quadrupole system (PMQ) designed, in collaboration with SIGMAPHI (Fr), to improve the ESS performances. In this work a description of the ESS system and some results of its characterization with conventional beams are reported, in order to provide a complete explanation of the acceptance calculation. Then, the matching with the PMQ system is presented and, finally, the results of preliminary simulations with a realistic laser-driven energy spectrum are discussed demonstrating the possibility to provide a good quality beam downstream the systems.

  12. Piezo-Phototronic Effect on Selective Electron or Hole Transport through Depletion Region of Vis-NIR Broadband Photodiode.

    Science.gov (United States)

    Zou, Haiyang; Li, Xiaogan; Peng, Wenbo; Wu, Wenzhuo; Yu, Ruomeng; Wu, Changsheng; Ding, Wenbo; Hu, Fei; Liu, Ruiyuan; Zi, Yunlong; Wang, Zhong Lin

    2017-08-01

    Silicon underpins nearly all microelectronics today and will continue to do so for some decades to come. However, for silicon photonics, the indirect band gap of silicon and lack of adjustability severely limit its use in applications such as broadband photodiodes. Here, a high-performance p-Si/n-ZnO broadband photodiode working in a wide wavelength range from visible to near-infrared light with high sensitivity, fast response, and good stability is reported. The absorption of near-infrared wavelength light is significantly enhanced due to the nanostructured/textured top surface. The general performance of the broadband photodiodes can be further improved by the piezo-phototronic effect. The enhancement of responsivity can reach a maximum of 78% to 442 nm illumination, the linearity and saturation limit to 1060 nm light are also significantly increased by applying external strains. The photodiode is illuminated with different wavelength lights to selectively choose the photogenerated charge carriers (either electrons or holes) passing through the depletion region, to investigate the piezo-phototronic effect on electron or hole transport separately for the first time. This is essential for studying the basic principles in order to develop a full understanding about piezotronics and it also enables the development of the better performance of optoelectronics. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Chamber transport

    International Nuclear Information System (INIS)

    Olson, Craig L.

    2001-01-01

    Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system

  14. Localisation of selected Ca2+-transport systems in rat's heart and kidney and their modulation by stress

    International Nuclear Information System (INIS)

    Zacikova, L.

    2000-01-01

    This thesis deals with the identification of selected calcium transport systems and their modulation by immobilization stress in rat heart and kidney. In our experiments we used normotensive (Sprague-Dawley, Wistar-Kyoto) and hypertensive (SHR) strains. We compared mRNA levels, protein expression and activity of the Na + /Ca 2+ exchanger from hearts of control animals, animals subjected to a single (once) or repeated (seven times) immobilization stress and from animals treated continually with cortisol. We have observed that immobilization stress increased both, gene expression and protein message of the Na + /Ca 2 + exchanger in rat cardiac left, but not right ventricle. This effect is not mediated through the glucocorticoid responsive element. We have found that cortisol decreased activity of the N a +/Ca 2+ exchanger without changing expression and protein amount of this transport system. IP3 receptor of type I and 2 was detected on mRNA levels in rat cardiac atria. Very small amounts of these receptors were observed in rat cardiac ventricles. Since it was difficult to detect these amounts in ventricles, we used 'seminested' PCR to verify expression of IP 3 R1 and 2 in cardiac ventricles. The highest levels of IP 3 R1 and 2 were expressed in left atria. Immobilization stress significantly increased mRNA IP 3 R1 and 2 in rat cardiac atria. We observed both, mRNA and type 1 IP 3 receptor's protein in renal medulla, but not in renal cortex. We have found that this receptor was approximately twice as abundant in normotensive as in genetically hypertensive rat kidney. Immobilization stress significantly down-regulated IP 3 R1 in renal medulla, but not in renal cortex. To investigate the role of NAADP in signaling we measured 45 Ca 2+ release from rat cardiac microsomes. We examined concentration and time dependence of 45 Ca 2+ release from rat cardiac microsomes. All these results could contribute to the understanding of Ca 2+ modulation in cardiac and kidney under

  15. GGVS. Ordinance on road transport of hazardous materials, including the European agreement on international road transport of hazardous materials (ADR), in their wording. Annexes A and B. Ordinances regarding exceptions from GGVS and from the ordinance on rail transport of hazardous materials, GGVE. Reasons. Selected guidelines. List of materials. 6. rev. and enlarged ed.

    International Nuclear Information System (INIS)

    Ridder, K.

    1990-01-01

    The brochure contains the following texts: (1) Ordinance on road transport of hazardous materials (GGVS), including the European agreement on international road transport of hazardous materials (ADR), as of 1990: Skeleton ordinance, annexes A and B, reasons given for the first version, and for the first amendment in 1988, execution guidelines - RS 002 (guidelines for executing the ordinance on road transport of hazardous materials, with catalogue of penalties), guidelines for drawing up written instructions for the event of accidents - RS 006, guiding principles for the training of vehicle conductors; (2) ordinance regarding exceptions from the ordinance on road transport of hazardous materials; (3) ordinance regarding exceptions from the ordinance on rail transport of hazardous materials; (4) selected guidelines: Technical guidelines TR IBC K 001, TRS 003, TRS 004, TRS 005, TRS 006; (5) listing of materials and objects governed by the ordinance on hazardous materials transport; (6) catalogue of penalties relative to road transport of hazardous materials. (orig./HP) [de

  16. Sediment transport primer: estimating bed-material transport in gravel-bed rivers

    Science.gov (United States)

    Peter Wilcock; John Pitlick; Yantao Cui

    2009-01-01

    This primer accompanies the release of BAGS, software developed to calculate sediment transport rate in gravel-bed rivers. BAGS and other programs facilitate calculation and can reduce some errors, but cannot ensure that calculations are accurate or relevant. This primer was written to help the software user define relevant and tractable problems, select appropriate...

  17. Point mutations in a nucleoside transporter gene from Leishmania donovani confer drug resistance and alter substrate selectivity

    OpenAIRE

    Vasudevan, Gayatri; Ullman, Buddy; Landfear, Scott M.

    2001-01-01

    Leishmania parasites lack a purine biosynthetic pathway and depend on surface nucleoside and nucleobase transporters to provide them with host purines. Leishmania donovani possess two closely related genes that encode high affinity adenosine-pyrimidine nucleoside transporters LdNT1.1 and LdNT1.2 and that transport the toxic adenosine analog tubercidin in addition to the natural substrates. In this study, we have characterized a drug-resistant clonal mutant of L. do...

  18. Improving nuclear envelope dynamics by EBV BFRF1 facilitates intranuclear component clearance through autophagy.

    Science.gov (United States)

    Liu, Guan-Ting; Kung, Hsiu-Ni; Chen, Chung-Kuan; Huang, Cheng; Wang, Yung-Li; Yu, Cheng-Pu; Lee, Chung-Pei

    2018-02-26

    Although a vesicular nucleocytoplasmic transport system is believed to exist in eukaryotic cells, the features of this pathway are mostly unknown. Here, we report that the BFRF1 protein of the Epstein-Barr virus improves vesicular transport of nuclear envelope (NE) to facilitate the translocation and clearance of nuclear components. BFRF1 expression induces vesicles that selectively transport nuclear components to the cytoplasm. With the use of aggregation-prone proteins as tools, we found that aggregated nuclear proteins are dispersed when these BFRF1-induced vesicles are formed. BFRF1-containing vesicles engulf the NE-associated aggregates, exit through from the NE, and putatively fuse with autophagic vacuoles. Chemical treatment and genetic ablation of autophagy-related factors indicate that autophagosome formation and autophagy-linked FYVE protein-mediated autophagic proteolysis are involved in this selective clearance of nuclear proteins. Remarkably, vesicular transport, elicited by BFRF1, also attenuated nuclear aggregates accumulated in neuroblastoma cells. Accordingly, induction of NE-derived vesicles by BFRF1 facilitates nuclear protein translocation and clearance, suggesting that autophagy-coupled transport of nucleus-derived vesicles can be elicited for nuclear component catabolism in mammalian cells.-Liu, G.-T., Kung, H.-N., Chen, C.-K., Huang, C., Wang, Y.-L., Yu, C.-P., Lee, C.-P. Improving nuclear envelope dynamics by EBV BFRF1 facilitates intranuclear component clearance through autophagy.

  19. The application of a selection of decision-making techniques by employees in a transport work environment in conjunction with their perceived decision-making success and practice

    Directory of Open Access Journals (Sweden)

    Theuns F.J. Oosthuizen

    2014-03-01

    Full Text Available A lack of optimum selection and application of decision-making techniques, in conjunction with suitable decision-making practice and perception of employees in a transport work environment demands attention to improve overall performance. Although multiple decision-making techniques exist, five prevalent techniques were considered in this article, namely the Kepner-Tregoe, Delphi, stepladder, nominal group and brainstorming techniques. A descriptive research design was followed, using an empirical survey which was conducted among 210 workers employed in a transport work environment and studying in the field of transport management. The purpose was to establish to what extent the five decision-making techniques are used in their work environment and furthermore how the decision-making practice of using gut-feel and/or a step-by-step decision-making process and their perception of their decision-making success relate. The research confirmed that the use of decision-making techniques is correlated to perceived decision-making success. Furthermore, the Kepner-Tregoe, stepladder, Delphi and brainstorming techniques are associated with a step-by-step decision-making process. No significant association was confirmed between the use of gut-feel and decision-making techniques. Brainstorming was found to be the technique most frequently used by transport employees; however, it has limitations as a comprehensive decision-making technique. Employees working in a transport work environment need training in order to select and use the four comprehensive decision-making techniques.

  20. Interactions with selected drug renal transporters and transporter-mediated cytotoxicity in antiviral agents from the group of acyclic nucleoside phosphonates

    Czech Academy of Sciences Publication Activity Database

    Mandíková, J.; Volková, M.; Pávek, P.; Česnek, Michal; Janeba, Zlatko; Kubíček, V.; Trejtnar, F.

    2013-01-01

    Roč. 311, č. 3 (2013), s. 135-146 ISSN 0300-483X Institutional support: RVO:61388963 Keywords : hOAT1 * hCNTs * MDR1 * BCRP * nephrotoxicity * transmembrane transport Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 3.745, year: 2013

  1. Gram-scale solution-phase synthesis of selective sodium bicarbonate Co-transport Inhibitor S0859

    DEFF Research Database (Denmark)

    Larsen, Ann Møller; Krogsgaard-Larsen, Niels; Lauritzen, Gitte

    2012-01-01

    Na+-coupled HCO3- transporters (NBCs) mediate the transport of bicarbonate ions across cell membranes and are thus ubiquitous regulators of intracellular pH. NBC dysregulation is associated with a range of diseases; for instance, NBCn1 is strongly up-regulated in a model of ErbB2-dependent breast...

  2. Online interprofessional education facilitation: A scoping review.

    Science.gov (United States)

    Evans, Sherryn Maree; Ward, Catherine; Reeves, Scott

    2018-04-22

    The use of online media to deliver interprofessional education (IPE) is becoming more prevalent across health professions education settings. Facilitation of IPE activities is known to be critical to the effective delivery of IPE, however, specifics about the nature of online IPE facilitation remains unclear. To explore the health professions education literature to understand the extent, range and nature of research on online IPE facilitation. Scoping review methodology was used to guide a search of four electronic databases for relevant papers. Of the 2095 abstracts initially identified, after screening of both abstracts and full-text papers, 10 studies were selected for inclusion in this review. Following abstraction of key information from each study, a thematic analysis was undertaken. Three key themes emerged to describe the nature of the IPE facilitation literature: (1) types of online IPE facilitation contributions, (2) the experience of online IPE facilitation and (3) personal outcomes of online IPE facilitation. These IPE facilitation themes were particularly focused on facilitation of interprofessional student teams on an asynchronous basis. While the included studies provide some insight into the nature of online IPE facilitation, future research is needed to better understand facilitator contributions, and the facilitation experience and associated outcomes, both relating to synchronous and asynchronous online environments.

  3. Selective transport of palynomorphs in marine turbiditic deposits: An example from the Ascension-Monterey Canyon system offshore central California

    Science.gov (United States)

    McGann, Mary

    2017-01-01

    The pollen assemblage of a deep-sea core (15G) collected at lower bathyal depths (3491 m) on a levee of Monterey Canyon off central California was investigated to gain insights into the delivery processes of terrigenous material to submarine fans and the effect this transport has on the palynological record. Thirty-two samples were obtained down the length of the core, 19 from hemipelagic and mixed mud deposits considered to be the background record, and 13 others from displaced flow deposits. The pollen record obtained from the background samples documents variations in the terrestrial flora as it adapted to changing climatic conditions over the last 19,000 cal yrs BP. A Q-mode cluster analysis defined three pollen zones: a Glacial Pollen Zone (ca. 20,000–17,000 cal yr BP), an overlying Transitional Pollen Zone (ca. 17,000–11,500 cal yr BP), and an Interglacial Pollen Zone (ca. 11,500 cal yr BP to present). Another Q-mode cluster analysis, of both the background mud and flow deposits, also defined these three pollen zones, but four of the 13 turbiditic deposits were assigned to pollen zones older than expected by their stratigraphic position. This was due to these samples containing statistically significant fewer palynomorphs than the background muds as well as being enriched (∼10–35% in some cases) in hydraulically-efficient Pinus pollen. A selective bias in the pollen assemblage, such as demonstrated here, may result in incorrect interpretations (e.g., climatic shifts or environmental perturbations) based on the floral record, indicating turbiditic deposits should be avoided in marine palynological studies. Particularly in the case of fine-grained flow deposits that may not be visually distinct, granulometry and grain size frequency distribution curves may not be enough to identify these biased deposits. Determining the relative abundance and source of displaced shallow-water benthic foraminifera entrained in these sediments serves as an excellent

  4. Formulation of optimal international freight transport objective

    Directory of Open Access Journals (Sweden)

    A. Jarašūnienė

    2002-10-01

    Full Text Available To increase the attraction of Lithuania as a transit country striving to promote carriers' border crossing activities and facilitate customs clearance procedures as well as freight delivery to clients it is necessary to identify the main obstacles, to analyse them and to select adequate measures and means for their elimination. Therefore, on the basis of the formulation of transport freight management objective, as well as basing on the assessment of indeterminacy of external impacts, it would be possible to deduce the main causes of idle time of transport means in customs, to estimate the dependence of service time in proportion to transport flow.

  5. Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Volume 2. Special test cases

    International Nuclear Information System (INIS)

    Simmons, C.S.; Cole, C.R.

    1985-08-01

    This document was written for the National Low-Level Waste Management Program to provide guidance for managers and site operators who need to select ground-water transport codes for assessing shallow-land burial site performance. The guidance given in this report also serves the needs of applications-oriented users who work under the direction of a manager or site operator. The guidelines are published in two volumes designed to support the needs of users having different technical backgrounds. An executive summary, published separately, gives managers and site operators an overview of the main guideline report. Volume 1, titled ''Guideline Approach,'' consists of Chapters 1 through 5 and a glossary. Chapters 2 through 5 provide the more detailed discussions about the code selection approach. This volume, Volume 2, consists of four appendices reporting on the technical evaluation test cases designed to help verify the accuracy of ground-water transport codes. 20 refs

  6. SSRI Facilitated Crack Dancing

    Directory of Open Access Journals (Sweden)

    Ravi Doobay

    2017-01-01

    Full Text Available Choreoathetoid movement secondary to cocaine use is a well-documented phenomenon better known as “crack dancing.” It consists of uncontrolled writhing movements secondary to excess dopamine from cocaine use. We present a 32-year-old male who had been using cocaine for many years and was recently started on paroxetine, a selective serotonin reuptake inhibitor (SSRI for worsening depression four weeks before presentation. He had been doing cocaine every 2 weeks for the last three years and had never “crack danced” before this episode. The authors have conducted a thorough literature review and cited studies that suggest “crack dancing” is associated with excess dopamine. There has never been a documented case report of an SSRI being linked with “crack dancing.” The authors propose that the excess dopaminergic effect of the SSRI lowered the dopamine threshold for “crack dancing.” There is a communication with the Raphe Nucleus and the Substantia Nigra, which explains how the SSRI increases dopamine levels. This is the first documented case of an SSRI facilitating the “crack dance.”

  7. Multi-Criteria Optimisation of Liquid Cargo Transport According to Linguistic Approach to the Route Selection Task

    Directory of Open Access Journals (Sweden)

    Guze Sambor

    2017-04-01

    Full Text Available The main aim of the paper is to present the possibility of use of the multi-criteria optimization method Analytical Hierarchy Process (AHP to liquid cargo transportation by sea. Finding the optimal solution is not simple. There are many factors influencing the shipping process. In the case of liquid cargo, the most important thing is the safety of the crew, ship, and environment. Therefore, the Mathematical Theory of Evidence is introduced and used to determine the optimal path in terms of time and safety of transport. Moreover, the details of liquid cargo transport process are described with particular attention to ship to ship operations. Besides, the basic concept of the AHP method, steps of the algorithm are introduced. Finally, the multicriteria optimization of the transport of the liquid cargo from the Persian Gulf to Port of Gdansk is done. It is based on the experts′ opinions.

  8. Study to determine the nature and extent of ozone and ozone precursor transport in selected areas of California. Final report

    International Nuclear Information System (INIS)

    Roberts, P.T.; Musarra, S.; Smith, T.B.; Lurmann, F.W.

    1992-04-01

    The project was designed to assess the contribution of transported pollutants to violations of the state ozone standard within the air basins covered by the report using existing data and advanced data analysis techniques. The objectives of the project were to determine the characteristics of ozone and ozone precursor transport within the California air basins covered by the report and to identify whether the contribution of transported pollutants to ozone violations in each downwind area was inconsequential, significant, or overwhelming, relative to locally-emitted pollutants. The precursor pollutants of interest were nitrogen oxides and reactive organic gases. The project evaluated transport to the following areas: The Broader Sacramento Area and the Upper Sacramento Valley; The North Central Coast Air Basin; The Southeast Desert Air Basin (SEDAB); and the Imperial County portion of the SEDAB

  9. Development of a selection tool for use in the identification, recruitment & retention of safe intermodal transportation workers.

    Science.gov (United States)

    2012-05-01

    A total of 486 transportation employees employed by a major railroad completed a series of : tests constructed for this project. These tests or instruments included the Denver Lifestyle : Questionnaire, a performance rating scale called the Employees...

  10. Identification of Selective Inhibitors of the Plasmodium falciparum Hexose Transporter PfHT by Screening Focused Libraries of Anti-Malarial Compounds.

    Directory of Open Access Journals (Sweden)

    Diana Ortiz

    Full Text Available Development of resistance against current antimalarial drugs necessitates the search for novel drugs that interact with different targets and have distinct mechanisms of action. Malaria parasites depend upon high levels of glucose uptake followed by inefficient metabolic utilization via the glycolytic pathway, and the Plasmodium falciparum hexose transporter PfHT, which mediates uptake of glucose, has thus been recognized as a promising drug target. This transporter is highly divergent from mammalian hexose transporters, and it appears to be a permease that is essential for parasite viability in intra-erythrocytic, mosquito, and liver stages of the parasite life cycle. An assay was developed that is appropriate for high throughput screening against PfHT based upon heterologous expression of PfHT in Leishmania mexicana parasites that are null mutants for their endogenous hexose transporters. Screening of two focused libraries of antimalarial compounds identified two such compounds that are high potency selective inhibitors of PfHT compared to human GLUT1. Additionally, 7 other compounds were identified that are lower potency and lower specificity PfHT inhibitors but might nonetheless serve as starting points for identification of analogs with more selective properties. These results further support the potential of PfHT as a novel drug target.

  11. 50 CFR 600.752 - Use of conveners and facilitators.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Use of conveners and facilitators. 600.752..., by consensus. The facilitator may be the same person as the convener used under paragraph (a) of this... facilitator, the FNP shall select, by consensus, a person to serve as facilitator. A person designated to...

  12. The application of a selection of decision-making techniques by employees in a transport work environment in conjunction with their perceived decision-making success and practice

    OpenAIRE

    Theuns F.J. Oosthuizen

    2014-01-01

    A lack of optimum selection and application of decision-making techniques, in conjunction with suitable decision-making practice and perception of employees in a transport work environment demands attention to improve overall performance. Although multiple decision-making techniques exist, five prevalent techniques were considered in this article, namely the Kepner-Tregoe, Delphi, stepladder, nominal group and brainstorming techniques. A descriptive research design was followed, using an empi...

  13. Facile spray-coating process for the fabrication of tunable adhesive superhydrophobic surfaces with heterogeneous chemical compositions used for selective transportation of microdroplets with different volumes.

    Science.gov (United States)

    Li, Jian; Jing, Zhijiao; Zha, Fei; Yang, Yaoxia; Wang, Qingtao; Lei, Ziqiang

    2014-06-11

    In this paper, tunable adhesive superhydrophobic ZnO surfaces have been fabricated successfully by spraying ZnO nanoparticle (NP) suspensions onto desired substrates. We regulate the spray-coating process by changing the mass percentage of hydrophobic ZnO NPs (which were achieved by modifying hydrophilic ZnO NPs with stearic acid) in the hydrophobic/hydrophilic ZnO NP mixtures to control heterogeneous chemical composition of the ZnO surfaces. Thus, the water adhesion on the same superhydrophobic ZnO surface could be effectively tuned by controlling the surface chemical composition without altering the surface morphology. Compared with the conventional tunable adhesive superhydrophobic surfaces, on which there were only three different water sliding angle values: lower than 10°, 90° (the water droplet is firmly pinned on the surface at any tilted angles), and the value between the two ones, the water adhesion on the superhydrophobic ZnO surfaces has been tuned effectively, on which the sliding angle is controlled from 2 ± 1° to 9 ± 1°, 21 ± 2°, 39 ± 3°, and 90°. Accordingly, the adhesive force can be adjusted from extremely low (∼2.5 μN) to very high (∼111.6 μN). On the basis of the different adhesive forces of the tunable adhesive superhydrophobic surfaces, the selective transportation of microdroplets with different volumes was achieved, which has never been reported before. In addition, we demonstrated a proof of selective transportation of microdroplets with different volumes for application in the droplet-based microreactors via our tunable adhesive superhydrophobic surfaces for the quantitative detection of AgNO3 and NaOH. The results reported herein realize the selective transportation of microdroplets with different volumes and we believe that this method would potentially be used in many important applications, such as selective water droplet transportation, biomolecular quantitative detection and droplet-based biodetection.

  14. Fluoroethoxy-1,4-diphenethylpiperidine and piperazine derivatives: Potent and selective inhibitors of [3H]dopamine uptake at the vesicular monoamine transporter-2.

    Science.gov (United States)

    Hankosky, Emily R; Joolakanti, Shyam R; Nickell, Justin R; Janganati, Venumadhav; Dwoskin, Linda P; Crooks, Peter A

    2017-12-15

    A small library of fluoroethoxy-1,4-diphenethyl piperidine and fluoroethoxy-1,4-diphenethyl piperazine derivatives were designed, synthesized and evaluated for their ability to inhibit [ 3 H]dopamine (DA) uptake at the vesicular monoamine transporter-2 (VMAT2) and dopamine transporter (DAT), [ 3 H]serotonin (5-HT) uptake at the serotonin transporter (SERT), and [ 3 H]dofetilide binding at the human-ether-a-go-go-related gene (hERG) channel. The majority of the compounds exhibited potent inhibition of [ 3 H]DA uptake at VMAT2, Ki changes in the nanomolar range (K i  = 0.014-0.073 µM). Compound 15d exhibited the highest affinity (K i  = 0.014 µM) at VMAT2, and had 160-, 5-, and 60-fold greater selectivity for VMAT2 vs. DAT, SERT and hERG, respectively. Compound 15b exhibited the greatest selectivity (>60-fold) for VMAT2 relative to all the other targets evaluated, and 15b had high affinity for VMAT2 (K i  = 0.073 µM). Compound 15b was considered the lead compound from this analog series due to its high affinity and selectivity for VMAT2. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Visual explorer facilitator's guide

    CERN Document Server

    Palus, Charles J

    2010-01-01

    Grounded in research and practice, the Visual Explorer™ Facilitator's Guide provides a method for supporting collaborative, creative conversations about complex issues through the power of images. The guide is available as a component in the Visual Explorer Facilitator's Letter-sized Set, Visual Explorer Facilitator's Post card-sized Set, Visual Explorer Playing Card-sized Set, and is also available as a stand-alone title for purchase to assist multiple tool users in an organization.

  16. Learning facilitating leadership

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard; Hansen, Mette Sanne

    2016-01-01

    This paper explains how engineering students at a Danish university acquired the necessary skills to become emergent facilitators of organisational development. The implications of this approach are discussed and related to relevant viewpoints and findings in the literature. The methodology deplo....... By connecting the literature, the authors’ and engineering students’ reflections on facilitator skills, this paper adds value to existing academic and practical discussions on learning facilitating leadership....

  17. Diversity in the glucose transporter-4 gene (SLC2A4 in humans reflects the action of natural selection along the old-world primates evolution.

    Directory of Open Access Journals (Sweden)

    Eduardo Tarazona-Santos

    Full Text Available BACKGROUND: Glucose is an important source of energy for living organisms. In vertebrates it is ingested with the diet and transported into the cells by conserved mechanisms and molecules, such as the trans-membrane Glucose Transporters (GLUTs. Members of this family have tissue specific expression, biochemical properties and physiologic functions that together regulate glucose levels and distribution. GLUT4 -coded by SLC2A4 (17p13 is an insulin-sensitive transporter with a critical role in glucose homeostasis and diabetes pathogenesis, preferentially expressed in the adipose tissue, heart muscle and skeletal muscle. We tested the hypothesis that natural selection acted on SLC2A4. METHODOLOGY/PRINCIPAL FINDINGS: We re-sequenced SLC2A4 and genotyped 104 SNPs along a approximately 1 Mb region flanking this gene in 102 ethnically diverse individuals. Across the studied populations (African, European, Asian and Latin-American, all the eight common SNPs are concentrated in the N-terminal region upstream of exon 7 ( approximately 3700 bp, while the C-terminal region downstream of intron 6 ( approximately 2600 bp harbors only 6 singletons, a pattern that is not compatible with neutrality for this part of the gene. Tests of neutrality based on comparative genomics suggest that: (1 episodes of natural selection (likely a selective sweep predating the coalescent of human lineages, within the last 25 million years, account for the observed reduced diversity downstream of intron 6 and, (2 the target of natural selection may not be in the SLC2A4 coding sequence. CONCLUSIONS: We propose that the contrast in the pattern of genetic variation between the N-terminal and C-terminal regions are signatures of the action of natural selection and thus follow-up studies should investigate the functional importance of different regions of the SLC2A4 gene.

  18. Containers, facilitators, innovators?

    DEFF Research Database (Denmark)

    Makkonen, Teemu; Merisalo, Maria; Inkinen, Tommi

    2018-01-01

    : are they containers, facilitators or innovators? This is investigated here through empirical material derived from 27 interviews with top departmental management in three Finnish cities (Helsinki, Espoo and Vantaa). The results show that local city governments (LCGs) consider cities as facilitators of innovation...

  19. Training facilitators and supervisors

    DEFF Research Database (Denmark)

    Kjær, Louise Binow; O Connor, Maja; Krogh, Kristian

    At the Master’s program in Medicine at Aarhus University, Denmark, we have developed a faculty development program for facilitators and supervisors in 4 progressing student modules in communication, cooperation, and leadership. 1) A course for module 1 and 3 facilitators inspired by the apprentic...

  20. Physiological adjustment to salt stress in Jatropha curcas is associated with accumulation of salt ions, transport and selectivity of K+, osmotic adjustment and K+/Na+ homeostasis.

    Science.gov (United States)

    Silva, E N; Silveira, J A G; Rodrigues, C R F; Viégas, R A

    2015-09-01

    This study assessed the capacity of Jatropha curcas to physiologically adjust to salinity. Seedlings were exposed to increasing NaCl concentrations (25, 50, 75 and 100 mm) for 15 days. Treatment without NaCl was adopted as control. Shoot dry weight was strongly reduced by NaCl, reaching values of 35% to 65% with 25 to 100 mm NaCl. The shoot/root ratio was only affected with 100 mm NaCl. Relative water content (RWC) increased only with 100 mm NaCl, while electrolyte leakage (EL) was much enhanced with 50 mm NaCl. The Na(+) transport rate to the shoot was more affected with 50 and 100 mm NaCl. In parallel, Cl(-) transport rate increased with 75 and 100 mm NaCl, while K(+) transport rate fell from 50 mm to 100 mm NaCl. In roots, Na(+) and Cl(-) transport rates fell slightly only in 50 mm (to Na(+)) and 50 and 100 mm (to Cl(-)) NaCl, while K(+) transport rate fell significantly with increasing NaCl. In general, our data demonstrate that J. curcas seedlings present changes in key physiological processes that allow this species to adjust to salinity. These responses are related to accumulation of Na(+) and Cl(-) in leaves and roots, K(+)/Na(+) homeostasis, transport of K(+) and selectivity (K-Na) in roots, and accumulation of organic solutes contributing to osmotic adjustment of the species. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  1. Application of sediment characteristics and transport conditions to resource management in selected main-stem reaches of the Upper Colorado River, Colorado and Utah, 1965-2007

    Science.gov (United States)

    Williams, Cory A.; Schaffrath, Keelin R.; Elliott, John G.; Richards, Rodney J.

    2013-01-01

    The Colorado River Basin provides habitat for 14 native fish, including 4 endangered species protected under the Federal Endangered Species Act of 1973. These endangered fish species once thrived in the Colorado River system, but water-resource development, including the building of numerous diversion dams and several large reservoirs, and the introduction of non-native fish, resulted in large reductions in the numbers and range of the four species through loss of habitat and stream function. Understanding how stream conditions and habitat change in response to alterations in streamflow is important for water administrators and wildlife managers and can be determined from an understanding of sediment transport. Characterization of the processes that are controlling sediment transport is an important first step in identifying flow regimes needed for restored channel morphology and the sustained recovery of endangered fishes within these river systems. The U.S. Geological Survey, in cooperation with the Upper Colorado River Endangered Fish Recovery Program, Bureau of Reclamation, U.S. Fish and Wildlife Service, Argonne National Laboratory, Western Area Power Administration, and Wyoming State Engineer’s Office, began a study in 2004 to characterize sediment transport at selected locations on the Colorado, Gunnison, and Green Rivers to begin addressing gaps in existing datasets and conceptual models of the river systems. This report identifies and characterizes the relation between streamflow (magnitude and timing) and sediment transport and presents the findings through discussions of (1) suspended-sediment transport, (2) incipient motion of streambed material, and (3) a case study of sediment-transport conditions for a reach of the Green River identified as a razorback sucker spawning habitat (See report for full abstract).

  2. Characterization of the serotonin transporter knockout rat : A selective change in the functioning of the serotonergic system

    NARCIS (Netherlands)

    Homberg, J. R.; Olivier, J.D.A.; Smits, B. M. G.; Mul, J. D.; Mudde, J.; Verheul, M.; Nieuwenhuizen, O. F. M.; Cools, A. R.; Ronken, E; Cremers, Thomas; Schoffelmeere, A. N. M.; Ellenbroeik, B. A.; Cuppen, E.

    2007-01-01

    Serotonergic signaling is involved in many neurobiological processes and disturbed 5-HT homeostasis is implicated in a variety of psychiatric and addictive disorders. Here, we describe the functional characterization of the serotonin transporter (SERT) knockout rat model, that is generated by

  3. Characterization of the serotonin transporter knockout rat: a selective change in the functioning of the serotonergic system.

    NARCIS (Netherlands)

    Homberg, J.R.; Olivier, J.D.A.; Smits, B.M.; Mul, J.D.; Mudde, J.; Verheul, M.; Nieuwenhuizen, O.F.; Cools, A.R.; Ronken, E.; Cremers, T.; Schoffelmeer, A.N.; Ellenbroek, B.A.; Cuppen, E.

    2007-01-01

    Serotonergic signaling is involved in many neurobiological processes and disturbed 5-HT homeostasis is implicated in a variety of psychiatric and addictive disorders. Here, we describe the functional characterization of the serotonin transporter (SERT) knockout rat model, that is generated by

  4. A comparison of radiation doses and risks between spent fuel transport/storage and selected non-nuclear activities

    International Nuclear Information System (INIS)

    Pennington, C.W.

    2003-01-01

    Spent fuel transport and storage have achieved an exemplary safety record over four decades within both the United States (US) and the global community at large. This paper offers an assessment demonstrating the safety of spent fuel transport and storage packagings relative to currently accepted but unregulated non-nuclear activities and practices within society. Over the last quarter of a century, several spent fuel transport and storage packaging test programmes have produced data that allow calculation of potential releases and population doses resulting from a terrorist attack. The US Department of Energy (DOE) has used this information to develop projected worst-case, low probability population exposures as part of the Final Environmental Impact Statement (FEIS) for the Yucca Mountain repository. The paper discusses potential population exposures from these packagings based on analysis and testing under beyond-design-basis (BDB) events, including missile attacks, and then defines and defends an acceptance criterion for the bounding outcomes of these events, based upon current accepted activities within society that produce high radiation doses to the general public. These activities involve unregulated technologies and practices within society that yield population doses significantly exceeding those that would result from such hypothetical and highly improbable events as a terrorist missile attack on a spent fuel transport or storage packaging. In particular, technologically enhanced natural radiation (TENR) exposures from building materials, farming, and masonry construction are highlighted. Recent landmark work by the US National Academy of Sciences (NAS) and by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) are cited in support of this assessment, along with work from the US Environmental Protection Agency (EPA). From this compelling evidence, it is concluded that spent fuel transport and storage represent a low

  5. N-linked glycans do not affect plasma membrane localization of multidrug resistance protein 4 (MRP4) but selectively alter its prostaglandin E2 transport activity.

    Science.gov (United States)

    Miah, M Fahad; Conseil, Gwenaëlle; Cole, Susan P C

    2016-01-22

    Multidrug resistance protein 4 (MRP4) is a member of subfamily C of the ATP-binding cassette superfamily of membrane transport proteins. MRP4 mediates the ATP-dependent efflux of many endogenous and exogenous solutes across the plasma membrane, and in polarized cells, it localizes to the apical or basolateral plasma membrane depending on the tissue type. MRP4 is a 170 kDa glycoprotein and here we show that MRP4 is simultaneously N-glycosylated at Asn746 and Asn754. Furthermore, confocal immunofluorescence studies showed that N-glycans do not affect MRP4's apical membrane localization in polarized LLC-PK1 cells or basolateral membrane localization in polarized MDCKI cells. However, vesicular transport assays showed that N-glycans differentially affect MRP4's ability to transport prostaglandin E2, but not estradiol glucuronide. Together these data indicate that N-glycosylation at Asn746 and Asn754 is not essential for plasma membrane localization of MRP4 but cause substrate-selective effects on its transport activity. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Barriers to and facilitators of sports participation for people with physical disabilities: a systematic review.

    Science.gov (United States)

    Jaarsma, E A; Dijkstra, P U; Geertzen, J H B; Dekker, R

    2014-12-01

    Most people with physical disabilities do not participate in sports regularly, which could increase the chances of developing secondary health conditions. Therefore, knowledge about barriers to and facilitators of sports participation is needed. Barriers and facilitators for people with physical disabilities other than amputation or spinal cord injuries (SCI) are unknown. The aim of this study was to provide an overview of the literature focusing on barriers to and facilitators of sports participation for all people with various physical disabilities. Four databases were searched using MeSH terms and free texts up to April 2012. The inclusion criteria were articles focusing on people with physical disabilities, sports and barriers and/or facilitators. The exclusion criteria were articles solely focusing on people with cognitive disabilities, sensory impairments or disabilities related to a recent organ transplant or similar condition. Fifty-two articles were included in this review, with 27 focusing on people with SCI. Personal barriers were disability and health; environmental barriers were lack of facilities, transport and difficulties with accessibility. Personal facilitators were fun and health, and the environmental facilitator was social contacts. Experiencing barriers to and facilitators of sports participation depends on age and type of disability and should be considered when advising people about sports. The extent of sports participation for people with physical disabilities also increases with the selection of the most appropriate sport. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Blockade of the high-affinity noradrenaline transporter (NET) by the selective 5-HT reuptake inhibitor escitalopram: an in vivo microdialysis study in mice

    Science.gov (United States)

    Nguyen, Hai T; Guiard, Bruno P; Bacq, Alexandre; David, Denis J; David, Indira; Quesseveur, Gaël; Gautron, Sophie; Sanchez, Connie; Gardier, Alain M

    2013-01-01

    BACKGROUND AND PURPOSE Escitalopram, the S(+)-enantiomer of citalopram is the most selective 5-HT reuptake inhibitor approved. Although all 5-HT selective reuptake inhibitors (SSRIs) increase extracellular levels of 5-HT ([5-HT]ext). some also enhance, to a lesser extent, extracellular levels of noradrenaline ([NA]ext). However, the mechanisms by which SSRIs activate noradrenergic transmission in the brain remain to be determined. EXPERIMENTAL APPROACH This study examined the effects of escitalopram, on both [5-HT]ext and [NA]ext in the frontal cortex (FCx) of freely moving wild-type (WT) and mutant mice lacking the 5-HT transporter (SERT−/−) by using intracerebral microdialysis. We explored the possibilities that escitalopram enhances [NA]ext, either by a direct mechanism involving the inhibition of the low- or high-affinity noradrenaline transporters, or by an indirect mechanism promoted by [5-HT]ext elevation. The forced swim test (FST) was used to investigate whether enhancing cortical [5-HT]ext and/or [NA]ext affected the antidepressant-like activity of escitalopram. KEY RESULTS In WT mice, a single systemic administration of escitalopram produced a significant increase in cortical [5-HT]ext and [NA]ext. As expected, escitalopram failed to increase cortical [5-HT]ext in SERT−/− mice, whereas its neurochemical effects on [NA]ext persisted in these mutants. In WT mice subjected to the FST, escitalopram increased swimming parameters without affecting climbing behaviour. Finally, escitalopram, at relevant concentrations, failed to inhibit cortical noradrenaline and 5-HT uptake mediated by low-affinity monoamine transporters. CONCLUSIONS AND IMPLICATIONS These experiments suggest that escitalopram enhances, although moderately, cortical [NA]extin vivo by a direct mechanism involving the inhibition of the high-affinity noradrenaline transporter (NET). PMID:22233336

  8. Selection of exception limits for all actinide nuclides based on revised criteria for safe international transport and including storage delay

    International Nuclear Information System (INIS)

    Lavarenne, C.; Rouyer, V.; Mennerdahl, D.; Dean, C.; Barton, N.; Jean, F.

    2004-01-01

    Since 1998, there have been some speculations about future transport of significant quantities and concentrations of other actinide nuclides than the four currently listed in the regulation for the safe transport of the radioactive material. Therefore, it raised a need to specify exception limits for such actinides. In order to define credible exception limits, it was necessary to have reasonably accurate data for all actinide nuclides. Then the DGTREN/participants decided to perform calculations with different codes (MONK, MCNP, CRISTAL and SCALE) and different cross-section libraries (JEF2.2, ENDFB, etc.). The parameters of interest (such as k-infinite, critical masses) were determined. This article presents the work achieved and the questions raised, e.g. related to the effect of the radioactive decay of the isotopes on the criticality risks. It also points out the need for an evolution of the regulation of the safe transport of radioactive materials and gives a proposition of modification for the IAEA requirements related to, firstly, the list of the fissile materials, secondly, the rule to determine the quantities of actinide nuclides that can be excepted from the requirements for the packages containing fissile materials

  9. The SPECT tracer [123I]ADAM binds selectively to serotonin transporters: a double-blind, placebo-controlled study in healthy young men

    International Nuclear Information System (INIS)

    Giessen, Elsmarieke van de; Booij, Jan

    2010-01-01

    The tracer 123 I-2-([2-({dimethylamino}methyl)phenyl]thio)-5-iodophenylamine ([ 123 I]ADAM) has been developed to image serotonin transporters (SERTs) with SPECT. Preclinical studies have shown that [ 123 I]ADAM binds selectively to SERTs. Moreover, initial human studies have shown that [ 123 I]ADAM binding could be blocked by selective serotonin reuptake inhibitors (SSRIs). However, in humans it has not been proven that [ 123 I]ADAM binds selectively to SERTs. We examined the in vivo availability of SERTs in 12 healthy young volunteers 5 h after bolus injection of [ 123 I]ADAM. To evaluate the selectivity of binding, four participants were pretreated (double-blinded design) with placebo, four with paroxetine (20 mg) and four with the dopamine/norepinephrine blocker methylphenidate (20 mg). SPECT studies were performed on a brain-dedicated system (Neurofocus), and the SPECT images were coregistered with individual MR scans of the brain. ADAM binding in SERT-rich brain areas and cerebellar cortex (representing non-specific binding) was assessed by drawing regions of interest (ROIs) on the individual MR images. Specific to non-specific ratios were used as the outcome measure. We found that specific to non-specific ratios were statistically significantly lower in paroxetine-pretreated participants than in placebo- or methylphenidate-pretreated participants. No such difference was found between groups pretreated with placebo or methylphenidate. Our preliminary findings suggest that [ 123 I]ADAM binds selectively to SERTs in human brain. (orig.)

  10. The Selection of Wagons for the Internal Transport of a Logistics Company: A Novel Approach Based on Rough BWM and Rough SAW Methods

    Directory of Open Access Journals (Sweden)

    Željko Stević

    2017-11-01

    Full Text Available The rationalization of logistics activities and processes is very important in the business and efficiency of every company. In this respect, transportation as a subsystem of logistics, whether internal or external, is potentially a huge area for achieving significant savings. In this paper, the emphasis is placed upon the internal transport logistics of a paper manufacturing company. It is necessary to rationalize the movement of vehicles in the company’s internal transport, that is, for the majority of the transport to be transferred to rail transport, because the company already has an industrial track installed in its premises. To do this, it is necessary to purchase at least two used wagons. The problem is formulated as a multi-criteria decision model with eight criteria and eight alternatives. The paper presents a new approach based on a combination of the Simple Additive Weighting (SAW method and rough numbers, which is used for ranking the potential solutions and selecting the most suitable one. The rough Best–Worst Method (BWM was used to determine the weight values of the criteria. The results obtained using a combination of these two methods in their rough form were verified by means of a sensitivity analysis consisting of a change in the weight criteria and comparison with the following methods in their conventional and rough forms: the Analytic Hierarchy Process (AHP, Technique for Ordering Preference by Similarity to Ideal Solution (TOPSIS and MultiAttributive Border Approximation area Comparison (MABAC. The results show very high stability of the model and ranks that are the same or similar in different scenarios.

  11. tran-SAS v1.0: a numerical model to compute catchment-scale hydrologic transport using StorAge Selection functions

    Directory of Open Access Journals (Sweden)

    P. Benettin

    2018-04-01

    Full Text Available This paper presents the tran-SAS package, which includes a set of codes to model solute transport and water residence times through a hydrological system. The model is based on a catchment-scale approach that aims at reproducing the integrated response of the system at one of its outlets. The codes are implemented in MATLAB and are meant to be easy to edit, so that users with minimal programming knowledge can adapt them to the desired application. The problem of large-scale solute transport has both theoretical and practical implications. On the one side, the ability to represent the ensemble of water flow trajectories through a heterogeneous system helps unraveling streamflow generation processes and allows us to make inferences on plant–water interactions. On the other side, transport models are a practical tool that can be used to estimate the persistence of solutes in the environment. The core of the package is based on the implementation of an age master equation (ME, which is solved using general StorAge Selection (SAS functions. The age ME is first converted into a set of ordinary differential equations, each addressing the transport of an individual precipitation input through the catchment, and then it is discretized using an explicit numerical scheme. Results show that the implementation is efficient and allows the model to run in short times. The numerical accuracy is critically evaluated and it is shown to be satisfactory in most cases of hydrologic interest. Additionally, a higher-order implementation is provided within the package to evaluate and, if necessary, to improve the numerical accuracy of the results. The codes can be used to model streamflow age and solute concentration, but a number of additional outputs can be obtained by editing the codes to further advance the ability to understand and model catchment transport processes.

  12. tran-SAS v1.0: a numerical model to compute catchment-scale hydrologic transport using StorAge Selection functions

    Science.gov (United States)

    Benettin, Paolo; Bertuzzo, Enrico

    2018-04-01

    This paper presents the tran-SAS package, which includes a set of codes to model solute transport and water residence times through a hydrological system. The model is based on a catchment-scale approach that aims at reproducing the integrated response of the system at one of its outlets. The codes are implemented in MATLAB and are meant to be easy to edit, so that users with minimal programming knowledge can adapt them to the desired application. The problem of large-scale solute transport has both theoretical and practical implications. On the one side, the ability to represent the ensemble of water flow trajectories through a heterogeneous system helps unraveling streamflow generation processes and allows us to make inferences on plant-water interactions. On the other side, transport models are a practical tool that can be used to estimate the persistence of solutes in the environment. The core of the package is based on the implementation of an age master equation (ME), which is solved using general StorAge Selection (SAS) functions. The age ME is first converted into a set of ordinary differential equations, each addressing the transport of an individual precipitation input through the catchment, and then it is discretized using an explicit numerical scheme. Results show that the implementation is efficient and allows the model to run in short times. The numerical accuracy is critically evaluated and it is shown to be satisfactory in most cases of hydrologic interest. Additionally, a higher-order implementation is provided within the package to evaluate and, if necessary, to improve the numerical accuracy of the results. The codes can be used to model streamflow age and solute concentration, but a number of additional outputs can be obtained by editing the codes to further advance the ability to understand and model catchment transport processes.

  13. Selected Abstracts of the 3rd Edition of Transport of High Risk Infants; Oxford (UK); August 31st-September 2nd, 2017

    OpenAIRE

    --- Various Authors

    2017-01-01

    Selected Abstracts of the 3rd Edition of Transport of High Risk Infants; Oxford (UK); August 31st-September 2nd, 2017ABS 1. MORTALITY RATE IN 23-30 WEEKS PRE­MATURE BORN IN LEVEL 2 HOSPITAL IN COMPARISON TO THOSE BORN IN TERTIARY-CARE HOSPITAL • J.P. Doray, J.L. DorayABS 2. THE QUEBEC AEROMEDICAL EXPERIENCE: EVACUATION OF NEONATES FROM AREAS IN EXTREME WEATHER CONDITIONS – IN­NOVATIONS IN SAFETY AND EFFICIENCY • É. Notebaert, J. Provencher, R. Bernier, S. Côté, S. KindABS 3. NASAL HIGH FLOW S...

  14. Fuzzy multi-objective approach for optimal selection of suppliers and transportation decisions in an eco-efficient closed loop supply chain network

    DEFF Research Database (Denmark)

    Govindan, Kannan; Darbari, Jyoti Dhingra; Agarwal, Vernika

    2017-01-01

    into the decision making process by selecting environmentally responsible suppliers to procure components based on sustainable criteria, choosing appropriate recovery options for end-of-use (EOU) inkjet printers, and planning an efficient transportation network design for reducing the carbon emission...... activities. A weighted fuzzy mathematical programming approach is utilised for generating a fuzzy, properly efficient solution as the desired compromised solution for the CLSC network problem configuration. The relevance of the model is justified using a real data set derived from a case study of the firm...... with higher sustainable performance and vehicles with lesser emission rate could substantially enhance firm's sustainable image and result in higher profits in the future....

  15. Role of molecular charge in nucleocytoplasmic transport.

    Directory of Open Access Journals (Sweden)

    Alexander Goryaynov

    Full Text Available Transport of genetic materials and proteins between the nucleus and cytoplasm of eukaryotic cells is mediated by nuclear pore complexes (NPCs. A selective barrier formed by phenylalanine-glycine (FG nucleoporins (Nups with net positive charges in the NPC allows for passive diffusion of signal-independent small molecules and transport-receptor facilitated translocation of signal-dependent cargo molecules. Recently, negative surface charge was postulated to be another essential criterion for selective passage through the NPC. However, the charge-driven mechanism in determining the transport kinetics and spatial transport route for either passive diffusion or facilitated translocation remains obscure. Here we employed high-speed single-molecule fluorescence microscopy with an unprecedented spatiotemporal resolution of 9 nm and 400 µs to uncover these mechanistic fundamentals for nuclear transport of charged substrates through native NPCs. We found that electrostatic interaction between negative surface charges on transiting molecules and the positively charged FG Nups, although enhancing their probability of binding to the NPC, never plays a dominant role in determining their nuclear transport mode or spatial transport route. A 3D reconstruction of transport routes revealed that small signal-dependent endogenous cargo protein constructs with high positive surface charges that are destined to the nucleus, rather than repelled from the NPC as suggested in previous models, passively diffused through an axial central channel of the NPC in the absence of transport receptors. Finally, we postulated a comprehensive map of interactions between transiting molecules and FG Nups during nucleocytoplasmic transport by combining the effects of molecular size, signal and surface charge.

  16. Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Volume 1. Guideline approach

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, C.S.; Cole, C.R.

    1985-05-01

    This document was written for the National Low-Level Waste Management Program to provide guidance for managers and site operators who need to select ground-water transport codes for assessing shallow-land burial site performance. The guidance given in this report also serves the needs of applications-oriented users who work under the direction of a manager or site operator. The guidelines are published in two volumes designed to support the needs of users having different technical backgrounds. An executive summary, published separately, gives managers and site operators an overview of the main guideline report. This volume includes specific recommendations for decision-making managers and site operators on how to use these guidelines. The more detailed discussions about the code selection approach are provided. 242 refs., 6 figs.

  17. Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Volume 1. Guideline approach

    International Nuclear Information System (INIS)

    Simmons, C.S.; Cole, C.R.

    1985-05-01

    This document was written for the National Low-Level Waste Management Program to provide guidance for managers and site operators who need to select ground-water transport codes for assessing shallow-land burial site performance. The guidance given in this report also serves the needs of applications-oriented users who work under the direction of a manager or site operator. The guidelines are published in two volumes designed to support the needs of users having different technical backgrounds. An executive summary, published separately, gives managers and site operators an overview of the main guideline report. This volume includes specific recommendations for decision-making managers and site operators on how to use these guidelines. The more detailed discussions about the code selection approach are provided. 242 refs., 6 figs

  18. The Mechanisms and Quantification of the Selective Permeability in Transport Across Biological Barriers : the Example of Kyotorphin

    NARCIS (Netherlands)

    Serrano, Isa D.; Freire, Joao M.; Carvalho, Miguel V.; Neves, Mafalda; Melo, Manuel N.; Castanho, Miguel A. R. B.

    2014-01-01

    This paper addresses the mechanisms behind selective endothelial permeability and their regulations. The singular properties of each of the seven blood-tissues barriers. Then, it further revisits the physical, quantitative meaning of permeability, and the way it should be measured based on sound

  19. Phylogenetic selection of target species in Amaryllidaceae tribe Haemantheae for acetylcholinesterase inhibition and affinity to the serotonin reuptake transport protein

    Science.gov (United States)

    We present phylogenetic analyses of 37 taxa of Amaryllidaceae, tribe Haemantheae and Amaryllis belladonna L. as an outgroup, in order to provide a phylogenetic framework for the selection of candidate plants for lead discoveries in relation to Alzheimer´s disease and depression. DNA sequences from t...

  20. Transport channel of secondary ion beam of experimental setup for selective laser ionization with gas cell GALS

    Science.gov (United States)

    Gulbekyan, G. G.; Zemlyanoy, S. G.; Bashevoy, V. V.; Ivanenko, I. A.; Kazarinov, N. Yu; Kazacha, V. I.; Osipov, N. F.

    2017-07-01

    GALS is the experimental setup intended for production and research of isobaric and isotopically pure heavy neutron-rich nuclei. The beam line consists of two parts. The initial part is used for transport of the primary 136Xe ion beam with the energy of 4.5-9.0 MeV/amu from the FLNR cyclotron U-400M to the Pb target for production of the studying ion beams. These beams have the following design parameters: the charge Z = +1, the mass A = 180-270 and the kinetic energy W = 40 keV. The second part placed after the target consists of the SPIG (QPIG) system, the accelerating gap, the electrostatic Einzel lens, 90-degree spectrometric magnet (calculated value of the mass-resolution is equal to 1400) and the beam line for the transportation of the ions from the magnet focal plane to a particle detector. The results of simulation of the particle dynamics and the basic parameters of all elements of the beam line are presented.

  1. Selective transport and incorporation of highly charged metal and metal complex ions in self-assembled polyelectrolyte multilayer membranes

    International Nuclear Information System (INIS)

    Toutianoush, Ali; Tieke, Bernd

    2002-01-01

    The transport of aqueous salts containing mono-, di- and trivalent metal and tetravalent metal complex ions across ultrathin polyvinylammonium/polyvinylsulphate (PVA/PVS) membranes is described. The membranes were prepared by electrostatic layer-by-layer (LBL) assembly of the two polyelectrolytes. Using spectroscopic measurements and permeability studies, it is demonstrated that the transport of copper(II) chloride, lanthanum(III) chloride, barium chloride and potassium hexacyanoferrate(II) is accompanied by the permanent incorporation of the metal and metal complex ions in the membrane. Upon the uptake of copper, lanthanum and hexacyanoferrate ions, the membranes become cross-linked so that the permeation rates of other salts not taken up by the membrane, e.g. sodium chloride, potassium chloride and magnesium chloride, are decreased. The uptake of barium ions leads to a decrease of the cross-linking density of the membrane so that the permeation rate of NaCl is increased. Possible mechanisms for the ion uptake are discussed

  2. Nanopolaritonics with a continuum of molecules: simulations of molecular-induced selectivity in plasmonics transport through a continuous Y-shape.

    Science.gov (United States)

    Neuhauser, Daniel

    2011-11-28

    Using the recent NF (near-field) formulation for electrodynamics on the nanoscale, we simulate transport in a Y-shape gold nanostructure in the presence of 2-level molecules. NF is shown to be easily integrated with the Liouville equation, producing a simple and efficient nanopolaritons (plasmons-excitons) solver, with a large time step. Two cases are considered: coating of the gold structure with molecular layers thinner than the structure, and filling space with aligned molecules. In both cases significant effects on the radiation transport are obtained even for low molecular densities. At low densities the effects are primarily an overall reduction of the plasmonics peak, but at higher densities there is a significant selectivity control by the molecules. A redshift is predicted, especially for the space-filling case. The combined nanopolariton shows qualitative hybridization, and the spectral peaks separate with increasing coupling, i.e., with increasing molecular densities. The results open the way to "control of light by light," i.e., controlling plasmonic light transport by inducing a change in the direction of the guiding molecular dipoles through radiation or other means.

  3. Targeting Type 2 Diabetes with C-Glucosyl Dihydrochalcones as Selective Sodium Glucose Co-Transporter 2 (SGLT2) Inhibitors: Synthesis and Biological Evaluation.

    Science.gov (United States)

    Jesus, Ana R; Vila-Viçosa, Diogo; Machuqueiro, Miguel; Marques, Ana P; Dore, Timothy M; Rauter, Amélia P

    2017-01-26

    Inhibiting glucose reabsorption by sodium glucose co-transporter proteins (SGLTs) in the kidneys is a relatively new strategy for treating type 2 diabetes. Selective inhibition of SGLT2 over SGLT1 is critical for minimizing adverse side effects associated with SGLT1 inhibition. A library of C-glucosyl dihydrochalcones and their dihydrochalcone and chalcone precursors was synthesized and tested as SGLT1/SGLT2 inhibitors using a cell-based fluorescence assay of glucose uptake. The most potent inhibitors of SGLT2 (IC 50 = 9-23 nM) were considerably weaker inhibitors of SGLT1 (IC 50 = 10-19 μM). They showed no effect on the sodium independent GLUT family of glucose transporters, and the most potent ones were not acutely toxic to cultured cells. The interaction of a C-glucosyl dihydrochalcone with a POPC membrane was modeled computationally, providing evidence that it is not a pan-assay interference compound. These results point toward the discovery of structures that are potent and highly selective inhibitors of SGLT2.

  4. Characterization of stormwater at selected South Carolina Department of Transportation maintenance yards and section shed facilities in Ballentine, Conway, and North Charleston, South Carolina, 2010-12

    Science.gov (United States)

    Journey, Celeste A.; Conlon, Kevin J.

    2014-01-01

    Increased impervious surfaces (driveways, parking lots, and buildings) and human activities (residential, industrial, and commercial) have been linked to substantial changes in both the quality and quantity of stormwater on a watershed scale (Brabec and others, 2002; Pitt and Maestre, 2005). Small-scale storage and equipment repair facilities increase impervious surfaces that prevent infiltration of stormwater, and these facilities accommodate activities that can introduce trace metals, organic compounds, and other contaminants to the facility’s grounds. Thus, these small facilities may contribute pollutants to the environment during storm events (U.S. Environmental Protection Agency, 1992). The South Carolina Department of Transportation (SCDOT) operates section shed and maintenance yard facilities throughout the State. Prior to this investigation, the SCDOT had no data to define the quality of stormwater leaving these facilities. To provide these data, the U.S. Geological Survey (USGS), in cooperation with the SCDOT, conducted an investigation to identify and quantify constituents that are transported in stormwater from two maintenance yards and a section shed in three different areas of South Carolina. The two maintenance yards, in North Charleston and Conway, S.C., were selected because they represent facilities where equipment and road maintenance materials are stored and complete equipment repair operations are conducted. The section shed, in Ballentine, S.C., was selected because it is a facility that stores equipment and road maintenance material. Characterization of the constituents that were transported in stormwater from these representative SCDOT maintenance facilities may be used by the SCDOT in the development of stormwater management plans for similar section shed and maintenance yard facilities throughout the State to improve stormwater quality.

  5. NASA N+3 Subsonic Fixed Wing Silent Efficient Low-Emissions Commercial Transport (SELECT) Vehicle Study. Revision A

    Science.gov (United States)

    Bruner, Sam; Baber, Scott; Harris,Chris; Caldwell, Nicholas; Keding, Peter; Rahrig, Kyle; Pho, Luck; Wlezian, Richard

    2010-01-01

    A conceptual commercial passenger transport study was performed to define a single vehicle for entry into service in the 2030 to 2035 timeframe, meeting customer demands as well as NASA goals for improved fuel economy, NOx emissions, noise, and operability into smaller airports. A study of future market and operational scenarios was used to guide the design of an advanced tube-and-wing configuration that utilized advanced material and structural concepts, an advanced three-shaft high-bypass turbofan engine, natural laminar flow technology, and a suite of other advanced technologies. This configuration was found to meet the goals for NOx emissions, noise, and field length. A 64 percent improvement in fuel economy compared to a current state-of-the-art airliner was achieved, which fell slightly short of the desired 70 percent goal. Technology maturation plans for the technologies used in the design were developed to help guide future research and development activities.

  6. Coal export facilitation

    International Nuclear Information System (INIS)

    Eeles, L.

    1998-01-01

    There is a wide range of trade barriers, particularly tariffs, in current and potential coal market. Commonwealth departments in Australia play a crucial role in supporting government industry policies. This article summarises some of more recent activities of the Department of Primary Industries and Energy (DPIE) in facilitating the export of Australian Coals. Coal export facilitation activities are designed to assist the Australian coal industry by directing Commonwealth Government resources towards issues which would be inappropriate or difficult for the industry to address itself

  7. Conceptual design of a crewed reusable space transportation system aimed at parabolic flights: stakeholder analysis, mission concept selection, and spacecraft architecture definition

    Science.gov (United States)

    Fusaro, Roberta; Viola, Nicole; Fenoglio, Franco; Santoro, Francesco

    2017-03-01

    This paper proposes a methodology to derive architectures and operational concepts for future earth-to-orbit and sub-orbital transportation systems. In particular, at first, it describes the activity flow, methods, and tools leading to the generation of a wide range of alternative solutions to meet the established goal. Subsequently, the methodology allows selecting a small number of feasible options among which the optimal solution can be found. For the sake of clarity, the first part of the paper describes the methodology from a theoretical point of view, while the second part proposes the selection of mission concepts and of a proper transportation system aimed at sub-orbital parabolic flights. Starting from a detailed analysis of the stakeholders and their needs, the major objectives of the mission have been derived. Then, following a system engineering approach, functional analysis tools as well as concept of operations techniques allowed generating a very high number of possible ways to accomplish the envisaged goals. After a preliminary pruning activity, aimed at defining the feasibility of these concepts, more detailed analyses have been carried out. Going on through the procedure, the designer should move from qualitative to quantitative evaluations, and for this reason, to support the trade-off analysis, an ad-hoc built-in mission simulation software has been exploited. This support tool aims at estimating major mission drivers (mass, heat loads, manoeuverability, earth visibility, and volumetric efficiency) as well as proving the feasibility of the concepts. Other crucial and multi-domain mission drivers, such as complexity, innovation level, and safety have been evaluated through the other appropriate analyses. Eventually, one single mission concept has been selected and detailed in terms of layout, systems, and sub-systems, highlighting also logistic, safety, and maintainability aspects.

  8. Asexual sporulation facilitates adaptation

    NARCIS (Netherlands)

    Zhang, Jianhua; Debets, A.J.M.; Verweij, P.E.; Melchers, W.J.G.; Zwaan, B.J.; Schoustra, S.E.

    2015-01-01

    Understanding the occurrence and spread of azole resistance in Aspergillus fumigatus is crucial for public health. It has been hypothesized that asexual sporulation, which is abundant in nature, is essential for phenotypic expression of azole resistance mutations in A. fumigatus facilitating

  9. Facilitators in Ambivalence

    Science.gov (United States)

    Karlsson, Mikael R.; Erlandson, Peter

    2018-01-01

    This is part of a larger ethnographical study concerning how school development in a local educational context sets cultural and social life in motion. The main data "in this article" consists of semi-structural interviews with teachers (facilitators) who have the responsibility of carrying out a project about formative assessment in…

  10. Facilitation of Adult Development

    Science.gov (United States)

    Boydell, Tom

    2016-01-01

    Taking an autobiographical approach, I tell the story of my experiences facilitating adult development, in a polytechnic and as a management consultant. I relate these to a developmental framework of Modes of Being and Learning that I created and elaborated with colleagues. I connect this picture with a number of related models, theories,…

  11. From Teaching to Facilitation

    DEFF Research Database (Denmark)

    de Graaff, Erik

    2013-01-01

    A shift from teaching to learning is characteristic of the introduction of Problem Based Learning (PBL) in an existing school. As a consequence the teaching staff has to be trained in skills like facilitating group work and writing cases. Most importantly a change in thinking about teaching...

  12. Trade Facilitation in Ethiopia:

    African Journals Online (AJOL)

    Tilahun_EK

    so doing, it attempts to examine how Ethiopia's WTO Accession and trade facilitation ... the more expensive imports, exports and production becomes rendering. Ethiopian ..... can reserve the right to refuse requests of importers for the fifth valuation method to ..... units may find it easier to deal with post clearance audit. In the ...

  13. The SPECT tracer [{sup 123}I]ADAM binds selectively to serotonin transporters: a double-blind, placebo-controlled study in healthy young men

    Energy Technology Data Exchange (ETDEWEB)

    Giessen, Elsmarieke van de [University of Amsterdam, Academic Medical Center, Graduate School Neurosciences Amsterdam, Department of Nuclear Medicine, Amsterdam (Netherlands); Booij, Jan [University of Amsterdam, Academic Medical Center, Graduate School Neurosciences Amsterdam, Department of Nuclear Medicine, Amsterdam (Netherlands); University of Amsterdam, Academic Medical Center, Department of Nuclear Medicine, F2-236, Amsterdam (Netherlands)

    2010-08-15

    The tracer {sup 123}I-2-([2-({l_brace}dimethylamino{r_brace}methyl)phenyl]thio)-5-iodophenylamine ([{sup 123}I]ADAM) has been developed to image serotonin transporters (SERTs) with SPECT. Preclinical studies have shown that [{sup 123}I]ADAM binds selectively to SERTs. Moreover, initial human studies have shown that [{sup 123}I]ADAM binding could be blocked by selective serotonin reuptake inhibitors (SSRIs). However, in humans it has not been proven that [{sup 123}I]ADAM binds selectively to SERTs. We examined the in vivo availability of SERTs in 12 healthy young volunteers 5 h after bolus injection of [{sup 123}I]ADAM. To evaluate the selectivity of binding, four participants were pretreated (double-blinded design) with placebo, four with paroxetine (20 mg) and four with the dopamine/norepinephrine blocker methylphenidate (20 mg). SPECT studies were performed on a brain-dedicated system (Neurofocus), and the SPECT images were coregistered with individual MR scans of the brain. ADAM binding in SERT-rich brain areas and cerebellar cortex (representing non-specific binding) was assessed by drawing regions of interest (ROIs) on the individual MR images. Specific to non-specific ratios were used as the outcome measure. We found that specific to non-specific ratios were statistically significantly lower in paroxetine-pretreated participants than in placebo- or methylphenidate-pretreated participants. No such difference was found between groups pretreated with placebo or methylphenidate. Our preliminary findings suggest that [{sup 123}I]ADAM binds selectively to SERTs in human brain. (orig.)

  14. The influence of selected containment structures on debris dispersal and transport following high pressure melt ejection from the reactor vessel

    International Nuclear Information System (INIS)

    Pilch, M.; Tarbell, W.W.; Brockmann, J.E.

    1988-09-01

    High pressure expulsion of molten core debris from the reactor pressure vessel may result in dispersal of the debris from the reactor cavity. In most plants, the cavity exits into the containment such that the debris impinges on structures. Retention of the debris on the structures may affect the further transport of the debris throughout the containment. Two tests were done with scaled structural shapes placed at the exit of 1:10 linear scale models of the Zion cavity. The results show that the debris does not adhere significantly to structures. The lack of retention is attributed to splashing from the surface and reentrainment in the gas flowing over the surface. These processes are shown to be applicable to reactor scale. A third experiment was done to simulate the annular gap between the reactor vessel and cavity wall. Debris collection showed that the fraction of debris exiting through the gap was greater than the gap-to-total flow area ratio. Film records indicate that dispersal was primarily by entrainment of the molten debris in the cavity. 29 refs., 36 figs., 11 tabs

  15. Effects of selected electron transport chain inhibitors on 24-h hydrogen production by Synechocystis sp. PCC 6803.

    Science.gov (United States)

    Burrows, Elizabeth H; Chaplen, Frank W R; Ely, Roger L

    2011-02-01

    One factor limiting biosolar hydrogen (H(2)) production from cyanobacteria is electron availability to the hydrogenase enzyme. In order to optimize 24-h H(2) production this study used Response Surface Methodology and Q2, an optimization algorithm, to investigate the effects of five inhibitors of the photosynthetic and respiratory electron transport chains of Synechocystis sp. PCC 6803. Over 3 days of diurnal light/dark cycling, with the optimized combination of 9.4 mM KCN (3.1 μmol 10(10) cells(-1)) and 1.5 mM malonate (0.5 μmol 10(10) cells(-1)) the H(2) production was 30-fold higher, in EHB-1 media previously optimized for nitrogen (N), sulfur (S), and carbon (C) concentrations (Burrows et al., 2008). In addition, glycogen concentration was measured over 24 h with two light/dark cycling regimes in both standard BG-11 and EHB-1 media. The results suggest that electron flow as well as glycogen accumulation should be optimized in systems engineered for maximal H(2) output. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. Analysis of selected energy security issues related to US crude oil and natural gas exploration, development, production, transportation and processing

    International Nuclear Information System (INIS)

    1990-10-01

    In July 1989, President Bush directed the Secretary of Energy to initiate the development of a comprehensive National Energy Strategy (NES) built upon a national consensus. The overall principle for the NES, as defined by the President and articulated by the Economic Policy Council (EPC), is the continuation of the successful policy of market reliance, consistent with the following goals: Balancing of energy, economic, and environmental concerns; and reduced dependence by the US and its friends and allies on potentially unreliable energy suppliers. The analyses presented in this report draw upon a large body of work previously conducted for DOE/Office of Fossil Energy, the US Department of Interior/Minerals Management Service (DOI/MMS), and the Gas Research Institute (GRI), referenced throughout the text of this report. This work includes assessments in the following areas: the potential of advanced oil and gas extraction technologies as improved through R ampersand D, along with the successful transfer of these technologies to the domestic petroleum industry; the economic and energy impacts of environmental regulations on domestic oil and gas exploration, production, and transportation; the potential of tax incentives to stimulate domestic oil and gas development and production; the potential environmental costs associated with various options for leasing for US oil and gas resources in the Outer Continental Shelf (OCS); and the economic impacts of environmental regulations affecting domestic crude oil refining

  17. Design and Synthesis of Novel and Selective Glycine Transporter-1 (GlyT1) Inhibitors with Memory Enhancing Properties.

    Science.gov (United States)

    Santora, Vincent J; Almos, Theresa A; Barido, Richard; Basinger, Jillian; Bellows, Chris L; Bookser, Brett Carder; Breitenbucher, J Guy; Broadbent, Nicola J; Cabebe, Clifford; Chai, Chih-Kun; Chen, Mi; Chow, Stephine; Chung, De Michael; Crickard, Lindsay; Danks, Anne M; Freestone, Graeme; Gitnick, Dany; Gupta, Varsha; Hoffmaster, Christine; Hudson, Andrew R; Kaplan, Alan P; Kennedy, Michael R; Lee, Dong; Limberis, James; Ly, Kiev; Mak, Chi Ching; Masatsugu, Brittany; Morse, Andrew C; Na, Jim; Neul, David; Nikpur, John; Peters, Marco; Petroski, Robert E; Renick, Joel; Sebring, Kristen; Sevidal, Samantha; Tabatabaei, Ali; Wen, Jenny; Yan, Yingzhuo; Yoder, Zachary W; Zook, Douglas

    2018-06-11

    We report here the identification and optimization of a novel series of potent GlyT1 inhibitors. A ligand design campaign that utilized known GlyT1 inhibitors as starting points led to the identification of a novel series of pyrrolo[3,4-c]pyrazoles amides (21-50) with good in vitro potency. Subsequent optimization of physicochemical and in vitro ADME properties produced several compounds with promising pharmacokinetic profiles. In vivo inhibition of GlyT1 was demonstrated for select compounds within this series by measuring the elevation of glycine in the cerebrospinal fluid (CSF) of rats after a single oral dosing of 10 mg/kg. Ultimately, an optimized lead, compound 46, demonstrated in vivo efficacy in a rat Novel Object Recognition (NOR) assay after oral dosing at 0.1, 1, and 3 mg/kg.

  18. Short description of the BIOS-model, and selection of biosphere parameters to be used in radionuclide transport and dose

    International Nuclear Information System (INIS)

    Jong, E.J. de; Koester, H.W.; Vries, W.J. de.

    1990-02-01

    In the framework of the PACOMA-project (Performance assessment of confinements for medium and alpha waste), initiated by the European Commission, possible future radiation doses, due to contamination of the biosphere by radionuclides originating from radioactive waste disposed in salt-formations, were calculated. In all cases considered radionuclides coming out of the geosphere enter a river. For the biosphere calculations the BIOS-model, developed by the NRPB in England, is used. A short description of the model, as well as of the adjustments made at the RIVM to calculate the total individual and collective doses and the subdoses of different exposure pathways is given. The values of biosphere parameters selected for the model are presented, together with the literature consulted. (author). 17 refs., 3 figs.; 2 tabs

  19. Occurrence and transport of selected constituents in streams near the Stibnite mining area, Central Idaho, 2012–14

    Science.gov (United States)

    Etheridge, Alexandra B.

    2015-12-07

    Mining of stibnite (antimony sulfide), tungsten, gold, silver, and mercury near the town of Stibnite in central Idaho has left a legacy of trace element contamination in local streams. Water-quality and streamflow monitoring data from a network of five streamflow-gaging stations were used to estimate trace-element and suspended-sediment loads and flow-weighted concentrations in the Stibnite mining area between 2012 and 2014. Measured concentrations of arsenic exceeded human health-based water-quality criteria at each streamflow-gaging station, except for Meadow Creek (site 2), which was selected to represent background conditions in the study area. Measured concentrations of antimony exceeded human health-based water-quality criteria at sites 3, 4, and 5.

  20. The orotate transporter oroP from Lactococcus lactis is required for orotate uptake and can be used both as a food-grade selection and counter-selection marker

    DEFF Research Database (Denmark)

    Defoor, Els Marie Celine; Martinussen, Jan

    The plasmid pDBORO conferred sensitivity of Lactococcus lactis towards 5´-Fluoroorotate. Moreover, by transformation, this plasmid was found to be essential for orotate dependent growth in a pyrimidine requiring strain. A single gene on pDBORO was required for growth on orotate, and was termed oro......P. Since the corresponding open reading frame, OroP showed the features of a membrane protein, OroP most likely is an orotate transporter. A number of strains like L. lactis and Bacillus subtilus have been shown to be unable to metabolize orotate. If the oroP gene was introduced into these strains......, they acquired the ability to utilize orotate. If the strains had a pyrimidine requirement, the oroP gene could function as a selectable marker when growing in the presence of orotate as sole pyrimidine source. In an otherwise resistant strain, oroP was shown to sensitize the strain towards the analog 5...

  1. Laser facilitates vaccination

    Directory of Open Access Journals (Sweden)

    Ji Wang

    2016-01-01

    Full Text Available Development of novel vaccine deliveries and vaccine adjuvants is of great importance to address the dilemma that the vaccine field faces: to improve vaccine efficacy without compromising safety. Harnessing the specific effects of laser on biological systems, a number of novel concepts have been proposed and proved in recent years to facilitate vaccination in a safer and more efficient way. The key advantage of using laser technology in vaccine delivery and adjuvantation is that all processes are initiated by physical effects with no foreign chemicals administered into the body. Here, we review the recent advances in using laser technology to facilitate vaccine delivery and augment vaccine efficacy as well as the underlying mechanisms.

  2. Facilitating Learning at Conferences

    DEFF Research Database (Denmark)

    Ravn, Ib; Elsborg, Steen

    2011-01-01

    The typical conference consists of a series of PowerPoint presentations that tend to render participants passive. Students of learning have long abandoned the transfer model that underlies such one-way communication. We propose an al-ternative theory of conferences that sees them as a forum...... for learning, mutual inspiration and human flourishing. We offer five design principles that specify how conferences may engage participants more and hence increase their learning. In the research-and-development effort reported here, our team collaborated with conference organizers in Denmark to introduce...... and facilitate a variety of simple learning techniques at thirty one- and two-day conferences of up to 300 participants each. We present ten of these techniques and data evaluating them. We conclude that if conference organizers allocate a fraction of the total conference time to facilitated processes...

  3. Mindfulness for group facilitation

    DEFF Research Database (Denmark)

    Adriansen, Hanne Kirstine; Krohn, Simon

    2014-01-01

    In this paper, we argue that mindfulness techniques can be used for enhancing the outcome of group performance. The word mindfulness has different connotations in the academic literature. Broadly speaking there is ‘mindfulness without meditation’ or ‘Western’ mindfulness which involves active...... thinking and ‘Eastern’ mindfulness which refers to an open, accepting state of mind, as intended with Buddhist-inspired techniques such as meditation. In this paper, we are interested in the latter type of mindfulness and demonstrate how Eastern mindfulness techniques can be used as a tool for facilitation....... A brief introduction to the physiology and philosophy of Eastern mindfulness constitutes the basis for the arguments of the effect of mindfulness techniques. The use of mindfulness techniques for group facilitation is novel as it changes the focus from individuals’ mindfulness practice...

  4. Wet-gas transport in the Mediterranean Sea. Selection of a combined kinetic hydrate/corrosion inhibitor system

    Energy Technology Data Exchange (ETDEWEB)

    Zettlitzer, M. [RWE Dea AG, Wietze (Germany); Rozengard, N.; Koeckritz, V. [Technical Univ. Freiberg (Germany); Malt, E. [RWE Dea AG (Egypt)

    2007-09-13

    Raw gas will be collected on a platform in the centre of the field. Due to volume and weight constraints, condensing fluids will not be separated from the gas on the platform so that the raw gas will be transported in three-phase mode (gas, water, and condensate) via a 33 km long pipeline to a gas treatment plant. Under the calculated pipeline pressure of about 100 barg, hydrate formation is - according to the outcome of thermodynamic simulations - to be expected at temperatures of 19 C and below while the pipeline may cool down to about 15 C in winter conditions. Due to logistical, environmental and economic reasons, RWE Dea decided to inhibit hydrate formation with kinetic hydrate inhibitors (KHI). As the gas also contains carbon dioxide, certain corrosivity was forecasted and addition of a corrosion inhibitor turned out to be necessary. Laboratory tests were carried out to confirm the feasibility of the concept and to define the required dosage of KHI. Service companies were contacted and several kinetic hydrate and corrosion inhibitors were screened. Experiments with the different chemicals were performed at the University of Freiberg in a high-pressure cell at the pipeline pressure of 100 barg. Hydrate formation was detected by continuous pressure registration during temperature changes and by observation through a glass window. In order to preselect the chemicals, first tests were performed with pure methane. These tests also served for calibration of the equipment with literature data and especially as an indication for the minimum chemical concentration required. A second test series was performed with synthetic gas in a composition close to that of the field gas under consideration in order to verify the results obtained with methane. Finally, the optimum kinetic hydrate inhibitor was identified as well as the required dosage concentration. Compatibility of KHI and corrosion inhibitor was experimentally proven. A further set of kinetic inhibitor tests with

  5. Common selective serotonin reuptake inhibitor side effects in older adults associated with genetic polymorphisms in the serotonin transporter and receptors: data from a randomized controlled trial.

    Science.gov (United States)

    Garfield, Lauren D; Dixon, David; Nowotny, Petra; Lotrich, Francis E; Pollock, Bruce G; Kristjansson, Sean D; Doré, Peter M; Lenze, Eric J

    2014-10-01

    Antidepressant side effects are a significant public health issue, associated with poor adherence, premature treatment discontinuation, and, rarely, significant harm. Older adults assume the largest and most serious burden of medication side effects. We investigated the association between antidepressant side effects and genetic variation in the serotonin system in anxious, older adults participating in a randomized, placebo-controlled trial of the selective serotonin reuptake inhibitor (SSRI) escitalopram. Adults (N = 177) aged ≥ 60 years were randomized to active treatment or placebo for 12 weeks. Side effects were assessed using the Udvalg fur Kliniske Undersøgelser side-effect rating scale. Genetic polymorphisms were putative functional variants in the promoters of the serotonin transporter and 1A and 2A receptors (5-HTTLPR [L/S + rs25531], HTR1A rs6295, HTR2A rs6311, respectively). Four significant drug-placebo side-effect differences were found: increased duration of sleep, dry mouth, diarrhea, and diminished sexual desire. Analyses using putative high- versus low-transcription genotype groupings revealed six pharmacogenetic effects: greater dry mouth and decreased sexual desire for the low- and high-expressing serotonin transporter genotypes, respectively, and greater diarrhea with the 1A receptor low-transcription genotype. Diminished sexual desire was experienced significantly more by high-expressing genotypes in the serotonin transporter, 1A, or 2A receptors. There was not a significant relationship between drug concentration and side effects nor a mean difference in drug concentration between low- and high-expressing genotypes. Genetic variation in the serotonin system may predict who develops common SSRI side effects and why. More work is needed to further characterize this genetic modulation and to translate research findings into strategies useful for more personalized patient care. Published by Elsevier Inc.

  6. Gram-scale solution-phase synthesis of selective sodium bicarbonate co-transport inhibitor S0859: in vitro efficacy studies in breast cancer cells.

    Science.gov (United States)

    Larsen, Ann M; Krogsgaard-Larsen, Niels; Lauritzen, Gitte; Olesen, Christina W; Honoré Hansen, Steen; Boedtkjer, Ebbe; Pedersen, Stine F; Bunch, Lennart

    2012-10-01

    Na(+)-coupled HCO(3)(-) transporters (NBCs) mediate the transport of bicarbonate ions across cell membranes and are thus ubiquitous regulators of intracellular pH. NBC dysregulation is associated with a range of diseases; for instance, NBCn1 is strongly up-regulated in a model of ErbB2-dependent breast cancer, a malignant and widespread cancer with no targeted treatment options, and single-nucleotide polymorphisms in NBCn1 genetically link to breast cancer development and hypertension. The N-cyanosulfonamide S0859 has been shown to selectively inhibit NBCs, and its availability on the gram scale is therefore of significant interest to the scientific community. Herein we describe a short and efficient synthesis of S0859 with an overall yield of 45 % from commercially available starting materials. The inhibitory effect of S0859 on recovery of intracellular pH after an acid load was verified in human and murine cancer cell lines in Ringer solutions. However, S0859 binds very strongly to components in plasma, and accordingly, measurements on isolated murine tissues showed no effect of S0859 at concentrations up to 50 μM. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. An InDel in the Promoter of Al-ACTIVATED MALATE TRANSPORTER9 Selected during Tomato Domestication Determines Fruit Malate Contents and Aluminum Tolerance[OPEN

    Science.gov (United States)

    Wang, Xin; Hu, Tixu; Zhang, Fengxia; Wang, Bing; Li, Changxin; Yang, Tianxia; Li, Hanxia; Lu, Yongen; Ye, Zhibiao

    2017-01-01

    Deciphering the mechanism of malate accumulation in plants would contribute to a greater understanding of plant chemistry, which has implications for improving flavor quality in crop species and enhancing human health benefits. However, the regulation of malate metabolism is poorly understood in crops such as tomato (Solanum lycopersicum). Here, we integrated a metabolite-based genome-wide association study with linkage mapping and gene functional studies to characterize the genetics of malate accumulation in a global collection of tomato accessions with broad genetic diversity. We report that TFM6 (tomato fruit malate 6), which corresponds to Al-ACTIVATED MALATE TRANSPORTER9 (Sl-ALMT9 in tomato), is the major quantitative trait locus responsible for variation in fruit malate accumulation among tomato genotypes. A 3-bp indel in the promoter region of Sl-ALMT9 was linked to high fruit malate content. Further analysis indicated that this indel disrupts a W-box binding site in the Sl-ALMT9 promoter, which prevents binding of the WRKY transcription repressor Sl-WRKY42, thereby alleviating the repression of Sl-ALMT9 expression and promoting high fruit malate accumulation. Evolutionary analysis revealed that this highly expressed Sl-ALMT9 allele was selected for during tomato domestication. Furthermore, vacuole membrane-localized Sl-ALMT9 increases in abundance following Al treatment, thereby elevating malate transport and enhancing Al resistance. PMID:28814642

  8. Extreme Population Differences in the Human Zinc Transporter ZIP4 (SLC39A4) Are Explained by Positive Selection in Sub-Saharan Africa

    Science.gov (United States)

    Pybus, Marc; Andrews, Glen K.; Lalueza-Fox, Carles; Comas, David; Sekler, Israel; de la Rasilla, Marco; Rosas, Antonio; Stoneking, Mark; Valverde, Miguel A.; Vicente, Rubén; Bosch, Elena

    2014-01-01

    Extreme differences in allele frequency between West Africans and Eurasians were observed for a leucine-to-valine substitution (Leu372Val) in the human intestinal zinc uptake transporter, ZIP4, yet no further evidence was found for a selective sweep around the ZIP4 gene (SLC39A4). By interrogating allele frequencies in more than 100 diverse human populations and resequencing Neanderthal DNA, we confirmed the ancestral state of this locus and found a strong geographical gradient for the derived allele (Val372), with near fixation in West Africa. In extensive coalescent simulations, we show that the extreme differences in allele frequency, yet absence of a classical sweep signature, can be explained by the effect of a local recombination hotspot, together with directional selection favoring the Val372 allele in Sub-Saharan Africans. The possible functional effect of the Leu372Val substitution, together with two pathological mutations at the same codon (Leu372Pro and Leu372Arg) that cause acrodermatitis enteropathica (a disease phenotype characterized by extreme zinc deficiency), was investigated by transient overexpression of human ZIP4 protein in HeLa cells. Both acrodermatitis mutations cause absence of the ZIP4 transporter cell surface expression and nearly absent zinc uptake, while the Val372 variant displayed significantly reduced surface protein expression, reduced basal levels of intracellular zinc, and reduced zinc uptake in comparison with the Leu372 variant. We speculate that reduced zinc uptake by the ZIP4-derived Val372 isoform may act by starving certain pathogens of zinc, and hence may have been advantageous in Sub-Saharan Africa. Moreover, these functional results may indicate differences in zinc homeostasis among modern human populations with possible relevance for disease risk. PMID:24586184

  9. Extreme population differences in the human zinc transporter ZIP4 (SLC39A4 are explained by positive selection in Sub-Saharan Africa.

    Directory of Open Access Journals (Sweden)

    Johannes Engelken

    2014-02-01

    Full Text Available Extreme differences in allele frequency between West Africans and Eurasians were observed for a leucine-to-valine substitution (Leu372Val in the human intestinal zinc uptake transporter, ZIP4, yet no further evidence was found for a selective sweep around the ZIP4 gene (SLC39A4. By interrogating allele frequencies in more than 100 diverse human populations and resequencing Neanderthal DNA, we confirmed the ancestral state of this locus and found a strong geographical gradient for the derived allele (Val372, with near fixation in West Africa. In extensive coalescent simulations, we show that the extreme differences in allele frequency, yet absence of a classical sweep signature, can be explained by the effect of a local recombination hotspot, together with directional selection favoring the Val372 allele in Sub-Saharan Africans. The possible functional effect of the Leu372Val substitution, together with two pathological mutations at the same codon (Leu372Pro and Leu372Arg that cause acrodermatitis enteropathica (a disease phenotype characterized by extreme zinc deficiency, was investigated by transient overexpression of human ZIP4 protein in HeLa cells. Both acrodermatitis mutations cause absence of the ZIP4 transporter cell surface expression and nearly absent zinc uptake, while the Val372 variant displayed significantly reduced surface protein expression, reduced basal levels of intracellular zinc, and reduced zinc uptake in comparison with the Leu372 variant. We speculate that reduced zinc uptake by the ZIP4-derived Val372 isoform may act by starving certain pathogens of zinc, and hence may have been advantageous in Sub-Saharan Africa. Moreover, these functional results may indicate differences in zinc homeostasis among modern human populations with possible relevance for disease risk.

  10. Constructing robust and highly-selective hydrogel membranes by bioadhesion-inspired method for CO 2 separation

    KAUST Repository

    Wu, Yingzhen; Zhou, Tiantian; Wu, Hong; Fu, Weixian; Wang, Xinru; Wang, Shaofei; Yang, Leixin; Wu, Xingyu; Ren, Yanxiong; Jiang, Zhongyi; Wang, Baoyi

    2018-01-01

    -size gas molecules and thus enhancing the CO2/CH4 selectivity. Moreover, the abundant amine groups from PDA nanoaggregates could facilitate CO2 transport. The optimized hybrid hydrogel membrane exhibited CO2/CH4 selectivity of 43.2, which was 43.85% higher

  11. Selected Abstracts of the 3rd Edition of Transport of High Risk Infants; Oxford (UK; August 31st-September 2nd, 2017

    Directory of Open Access Journals (Sweden)

    --- Various Authors

    2017-08-01

    Full Text Available Selected Abstracts of the 3rd Edition of Transport of High Risk Infants; Oxford (UK; August 31st-September 2nd, 2017ABS 1. MORTALITY RATE IN 23-30 WEEKS PRE­MATURE BORN IN LEVEL 2 HOSPITAL IN COMPARISON TO THOSE BORN IN TERTIARY-CARE HOSPITAL • J.P. Doray, J.L. DorayABS 2. THE QUEBEC AEROMEDICAL EXPERIENCE: EVACUATION OF NEONATES FROM AREAS IN EXTREME WEATHER CONDITIONS – IN­NOVATIONS IN SAFETY AND EFFICIENCY • É. Notebaert, J. Provencher, R. Bernier, S. Côté, S. KindABS 3. NASAL HIGH FLOW SUPPORT DURING NEONATAL RETRIEVAL IN VICTORIA, AUSTRALIA • V. Abraham, C. Roberts, B. Manley, L. Owen, M. Stewart, P. DavisABS 4. NEONATAL TRANSPORT TO AND FROM A REGIONAL LEVEL 2 CENTRE • C. Moore, M. Cassidy, M. Byrne, A. Bowden, J. Franta, I. Farombi, J. FitzsimonsABS 5. PASSIVE THERAPEUTIC HYPOTHERMIA DURING AMBULANCE AND HELICOPTER SECONDARY NEONATAL TRANSPORT IN NEONATES WITH HYPOXIC BRAIN INJURY: 10-YEARS RETROSPECTIVE SURVEY • M. Leben, M. Nolimal, I. Vidmar, S. GrosekABS 6. STABILIZATION OF CRITICALLY ILL NEW­BORNS: PREVENTION OF ACUTE KIDNEY INJURY • A. Babintseva, Y. Hodovanets, L. AgafonovaABS 7. TRANSPORT OF THE SURGICAL NEONATES • R. Pejaver, A. Poveidein, D. Winterbank-Scott, C. Keys, N. GuptaABS 8. AUDIT OF VENTILATED NEONATAL TRANS­FERS IN NORTHERN IRELAND FROM 1ST JANUARY 2017 UNTIL 1ST MAY 2017 • R. Moore, S. KnoxABS 9. “HUB AND SPOKE” ECMO IN NEONATES WITH MECONIUM ASPIRATION SYNDROME: A PRELIMINARY REPORT • N. Doglioni, D. Fichera, F. Zanella, M. Padalino, V. Vida, G. Stellin, P. Lago, D. TrevisanutoABS 10. INTRA-HOSPITAL TRANSPORTATION OF EX­TREMELY PRETERM INFANTS AND INCI­DENCE OF INTRAVENTRICULAR HAEMOR­RHAGES • N. Wadström, M. Breindahl, B. Hallberg, B. SkiöldABS 11. RISK OF POSTNATAL TRANSPORT AND OUT­COME OF LATE PRETERM INFANTS BORN AT NON-TERTIARY CENTRES: A RETRO­SPEC­TIVE COHORT STUDY • N. Doglioni, L. Salmaso, P. Facchin, D. TrevisanutoABS 12. COMPARING THREE METHODS OF THERA

  12. Transport Statistics - Transport - UNECE

    Science.gov (United States)

    Sustainable Energy Statistics Trade Transport Themes UNECE and the SDGs Climate Change Gender Ideas 4 Change UNECE Weekly Videos UNECE Transport Areas of Work Transport Statistics Transport Transport Statistics About us Terms of Reference Meetings and Events Meetings Working Party on Transport Statistics (WP.6

  13. Essence: Facilitating Software Innovation

    DEFF Research Database (Denmark)

    Aaen, Ivan

    2008-01-01

      This paper suggests ways to facilitate creativity and innovation in software development. The paper applies four perspectives – Product, Project, Process, and People –to identify an outlook for software innovation. The paper then describes a new facility–Software Innovation Research Lab (SIRL......) – and a new method concept for software innovation – Essence – based on views, modes, and team roles. Finally, the paper reports from an early experiment using SIRL and Essence and identifies further research....

  14. Transportation technology quick reference file

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, E.W. (ed.)

    1981-05-01

    This publication is a collection of items written by different authors on subjects relating to the transportation of radioactive materials. The purpose of the document is to meet the continuing need for information on specific subjects for dissemination to the public at their request. The subjects included were selected on the basis of the questions most often asked about radioactive materials and their transportation. Additional subjects are being considered and will be included in the future. The loose-leaf notebook format is used to facilitate the updating of this material. The data used in many of the papers represent the best available at time of publication and will be updated as more current information becomes available.

  15. Transportation technology quick reference file

    International Nuclear Information System (INIS)

    Shepherd, E.W.

    1981-05-01

    This publication is a collection of items written by different authors on subjects relating to the transportation of radioactive materials. The purpose of the document is to meet the continuing need for information on specific subjects for dissemination to the public at their request. The subjects included were selected on the basis of the questions most often asked about radioactive materials and their transportation. Additional subjects are being considered and will be included in the future. The loose-leaf notebook format is used to facilitate the updating of this material. The data used in many of the papers represent the best available at time of publication and will be updated as more current information becomes available

  16. Facilitating Knowledge Sharing

    DEFF Research Database (Denmark)

    Holdt Christensen, Peter

    knowledge sharing is to ensure that the exchange is seen as equitable for the parties involved, and by viewing the problems of knowledge sharing as motivational problems situated in different organizational settings, the paper explores how knowledge exchange can be conceptualized as going on in four...... distinct situations of exchange denominated organizational exchange yielding extrinsic rewards, organizational exchange yielding intrinsic rewards, financial exchange, and social exchange. The paper argues that each situation of exchange has distinct assumptions about individual behaviour...... and the intermediaries regulating the exchange, and facilitating knowledge sharing should therefore be viewed as a continuum of practices under the influence of opportunistic behaviour, obedience or organizational citizenship behaviour. Keywords: Knowledge sharing, motivation, organizational settings, situations...

  17. Macropores and macropore transport

    DEFF Research Database (Denmark)

    Iversen, Bo Vangsø; Lamandé, Mathieu; Torp, Søren Bent

    2012-01-01

    Preferential transport of water through soil macropores is a governing process in the facilitated transport of strongly sorbing compounds. The aim of this study was to investigate the relationships between macropore density and the hydraulic conductivity of the soil and to test the sampling...

  18. Occurrence and Transport of Diazinon in the Sacramento River and Selected Tributaries, California, during Two Winter Storms, January?February 2001

    Science.gov (United States)

    Dileanis, Peter D.; Brown, David L.; Knifong, Donna L.; Saleh, Dina

    2003-01-01

    Diazinon, an organophosphate insecticide, is applied as an orchard dormant spray in the Sacramento Valley during the winter months when the area receives most of its annual rainfall. During winter rainstorms that frequently follow dormant spray applications, some of the applied pesticide is transported in storm runoff to the Sacramento River and its tributaries. Diazinon is also used to control insect pests on residential and commercial properties in urban areas and is frequently detected in urban storm runoff draining into the Sacramento River system. Between January 24 and February 14, 2001, diazinon concentrations and loads were measured in the Sacramento River and selected tributaries during two winter storms that occurred after dormant spray applications were made to orchards in the Sacramento Valley. Water samples were collected at 21 sites that represented agricultural and urban inputs on a variety of scales, from small tributaries and drains representing local land use to main-stem river sites representing regional effects. Concentrations of diazinon ranged from below laboratory reporting levels to 1,380 nanograms per liter (ng/L), with a median of 55 ng/L during the first monitored storm and 26 ng/L during the second. The highest concentrations were observed in small channels draining predominantly agricultural land. About 26,000 pounds of diazinon were reported applied to agricultural land in the study area just before and during the monitoring period. About 0.2 percent of the applied insecticide appeared to be transported to the lower Sacramento River during that period. The source of about one third of the total load measured in the lower Sacramento River appears to be in the portion of the drainage basin upstream of the city of Colusa. About 12 percent of the diazinon load in the lower Sacramento River was transported from the Feather River Basin, which drains much of the mountainous eastern portions of the Sacramento River Basin. Diazinon use in the

  19. Decoupling urban transport from GHG emissions in Indian cities-A critical review and perspectives

    International Nuclear Information System (INIS)

    Li Jun

    2011-01-01

    How to sustain rapid economic and urban growth with minimised detriment to environment is a key challenge for sustainable development and climate change mitigation in developing countries, which face constraints of technical and financial resources scarcity as well as dearth of infrastructure governance capacity. This paper attempts to address this question by investigating the driving forces of transport demand and relevant policy measures that facilitate mitigating GHG emissions in the urban transport sector in Indian cities based on a critical review of the literature. Our overview of existing literature and international experiences suggests that it is critical to improve urban governance in transport infrastructure quality and develop efficient public transport, coupled with integrated land use/transport planning as well as economic instruments. This will allow Indian cities to embark on a sustainable growth pathway by decoupling transport services demand of GHG emissions in the longer term. Appropriate policy instruments need to be selected to reconcile the imperatives of economic and urban growth, aspiration to higher quality of life, improvements in social welfare, urban transport-related energy consumption and GHG emissions mitigation target in Indian cities. - Highlights: → Investigating the relevant policies that facilitate mitigating GHG emissions in urban transport in Indian cities. → Determining the factors of increase in energy demand and carbon emissions in transport. → Improving urban governance in transport infrastructure with integrated transport planning. → Designing and implementing the policy and economic instruments for low-carbon urban transport in India.

  20. Single-photon emission tomography imaging of serotonin transporters in the non-human primate brain with the selective radioligand [[sup 123]I]IDAM

    Energy Technology Data Exchange (ETDEWEB)

    Acton, P.D.; Kung Mei-Ping; Mu Mu; Ploessl, K.; Hou, C.; Siciliano, M.; Oya Shunichi (Department of Radiology, University of Pennsylvania, Philadelphia, PA (United States)); Kung, H.F. (Department of Radiology, University of Pennsylvania, Philadelphia, PA (United States) Department of Pharmacology, University of Pennsylvania, Philadelphia (United States))

    1999-08-01

    A new radioligand, 5-iodo-2-[[2-2-[(dimethylamino)methyl]phenyl]thio]benzyl alcohol ([[sup 123]I]IDAM), has been developed for selective single-photon emission tomography (SPET) imaging of SERT. In vitro binding studies suggest a high selectivity of IDAM for SERT (K[sub i]=0.097 nM), with considerably lower affinities for norepinephrine and dopamine transporters (NET K[sub i]= 234 nM and DAT K[sub i]>10 [mu]M, respectively). In this study the biodistribution of SERT in the baboon brain was investigated in vivo using [[sup 123]I]IDAM and SPET imaging. Dynamic sequences of SPET scans were performed on three female baboons (Papio anubis) after injection of 555 MBq of [[sup 123]I]IDAM. Displacing doses (1 mg/kg) of the selective SERT ligand (+)McN5652 were administered 90-120 min after injection of [[sup 123]I]IDAM. Similar studies were performed using a NET inhibitor, nisoxetine, and a DAT blocker, methylphenidate. After 60-120 min, the regional distribution of tracer within the brain reflected the characteristic distribution of SERT, with the highest uptake in the midbrain area (hypothalamus, raphe nucleus, substantia nigra), and the lowest uptake in the cerebellum (an area presumed free of SERT). Peak specific binding in the midbrain occurred at 120 min, with a ratio to the cerebellum of 1.80[+-]0.13. At 30 min, 85% of the radioactivity in the blood was metabolite. Following injection of a competing SERT ligand, (+)McN5652, the tracer exhibited rapid washout from areas with high concentrations of SERT (dissociation rate constant in the midbrain, averaged over three baboons, k[sub off]=0.025[+-]0.002 min[sup -1]), while the cerebellar activity distribution was undisturbed (washout rate 0.0059[+-] 0.0003 min[sup -1]). Calculation of tracer washout rate pixel-by-pixel enabled the generation of parametric images of the dissociation rate constant. Similar studies using nisoxetine and methylphenidate had no effect on the distribution of [[sup 123]I]IDAM in the brain

  1. Computer code selection criteria for flow and transport code(s) to be used in undisturbed vadose zone calculations for TWRS environmental analyses

    International Nuclear Information System (INIS)

    Mann, F.M.

    1998-01-01

    The Tank Waste Remediation System (TWRS) is responsible for the safe storage, retrieval, and disposal of waste currently being held in 177 underground tanks at the Hanford Site. In order to successfully carry out its mission, TWRS must perform environmental analyses describing the consequences of tank contents leaking from tanks and associated facilities during the storage, retrieval, or closure periods and immobilized low-activity tank waste contaminants leaving disposal facilities. Because of the large size of the facilities and the great depth of the dry zone (known as the vadose zone) underneath the facilities, sophisticated computer codes are needed to model the transport of the tank contents or contaminants. This document presents the code selection criteria for those vadose zone analyses (a subset of the above analyses) where the hydraulic properties of the vadose zone are constant in time the geochemical behavior of the contaminant-soil interaction can be described by simple models, and the geologic or engineered structures are complicated enough to require a two-or three dimensional model. Thus, simple analyses would not need to use the fairly sophisticated codes which would meet the selection criteria in this document. Similarly, those analyses which involve complex chemical modeling (such as those analyses involving large tank leaks or those analyses involving the modeling of contaminant release from glass waste forms) are excluded. The analyses covered here are those where the movement of contaminants can be relatively simply calculated from the moisture flow. These code selection criteria are based on the information from the low-level waste programs of the US Department of Energy (DOE) and of the US Nuclear Regulatory Commission as well as experience gained in the DOE Complex in applying these criteria. Appendix table A-1 provides a comparison between the criteria in these documents and those used here. This document does not define the models (that

  2. Practice Facilitators' and Leaders' Perspectives on a Facilitated Quality Improvement Program.

    Science.gov (United States)

    McHugh, Megan; Brown, Tiffany; Liss, David T; Walunas, Theresa L; Persell, Stephen D

    2018-04-01

    Practice facilitation is a promising approach to helping practices implement quality improvements. Our purpose was to describe practice facilitators' and practice leaders' perspectives on implementation of a practice facilitator-supported quality improvement program and describe where their perspectives aligned and diverged. We conducted interviews with practice leaders and practice facilitators who participated in a program that included 35 improvement strategies aimed at the ABCS of heart health (aspirin use in high-risk individuals, blood pressure control, cholesterol management, and smoking cessation). Rapid qualitative analysis was used to collect, organize, and analyze the data. We interviewed 17 of the 33 eligible practice leaders, and the 10 practice facilitators assigned to those practices. Practice leaders and practice facilitators both reported value in the program's ability to bring needed, high-quality resources to practices. Practice leaders appreciated being able to set the schedule for facilitation and select among the 35 interventions. According to practice facilitators, however, relying on practice leaders to set the pace of the intervention resulted in a lower level of program intensity than intended. Practice leaders preferred targeted assistance, particularly electronic health record documentation guidance and linkages to state smoking cessation programs. Practice facilitators reported that the easiest interventions were those that did not alter care practices. The dual perspectives of practice leaders and practice facilitators provide a more holistic picture of enablers and barriers to program implementation. There may be greater opportunities to assist small practices through simple, targeted practice facilitator-supported efforts rather than larger, comprehensive quality improvement projects. © 2018 Annals of Family Medicine, Inc.

  3. Transportation statistics annual report 2009

    Science.gov (United States)

    2009-01-01

    The Transportation Statistics Annual Report (TSAR) presents data and information selected by the Bureau of Transportation Statistics (BTS), a component of the U.S. Department of Transportation's (USDOT's) Research and Innovative Technology Administra...

  4. Molecular determinants of transport stimulation of EAAT2 are located at interface between the trimerization and substrate transport domains.

    Science.gov (United States)

    Mortensen, Ole V; Liberato, José L; Coutinho-Netto, Joaquim; Dos Santos, Wagner F; Fontana, Andréia C K

    2015-04-01

    Excitatory amino acid transporters (EAATs) regulate glutamatergic signal transmission by clearing extracellular glutamate. Dysfunction of these transporters has been implicated in the pathogenesis of various neurological disorders. Previous studies have shown that venom from the spider Parawixia bistriata and a purified compound (Parawixin1) stimulate EAAT2 activity and protect retinal tissue from ischemic damage. In the present study, the EAAT2 subtype specificity of this compound was explored, employing chimeric proteins between EAAT2 and EAAT3 transporter subtypes and mutants to characterize the structural region targeted by the compound. This identified a critical residue (Histidine-71 in EAAT2 and Serine-45 in EAAT3) in transmembrane domain 2 (TM2) to be important for the selectivity between EAAT2 and EAAT3 and for the activity of the venom. Using the identified residue in TM2 as a structural anchor, several neighboring amino acids within TM5 and TM8 were identified to also be important for the activity of the venom. This structural domain of the transporter lies at the interface of the rigid trimerization domain and the central substrate-binding transport domain. Our studies suggest that the mechanism of glutamate transport enhancement involves an interaction with the transporter that facilitates the movement of the transport domain. We identified a domain (purple star) in the glutamate transporter EAAT2 that is important for transport stimulation through a spider venom, and suggest a mechanism for enhanced transporter function through facilitated substrate translocation (arrow). Because the dysfunction of glutamate transporters is implicated in the pathogenesis of neurological disorders, understanding the mechanisms of enhanced transport could have therapeutic implications. © 2015 International Society for Neurochemistry.

  5. Theory of contributon transport

    International Nuclear Information System (INIS)

    Painter, J.W.; Gerstl, S.A.W.; Pomraning, G.C.

    1980-10-01

    A general discussion of the physics of contributon transport is presented. To facilitate this discussion, a Boltzmann-like transport equation for contributons is obtained, and special contributon cross sections are defined. However, the main goal of this study is to identify contributon transport equations and investigate possible deterministic solution techniques. Four approaches to the deterministic solution of the contributon transport problem are investigated. These approaches are an attempt to exploit certain attractive properties of the contributon flux, psi = phi phi + , where phi and phi + are the solutions to the forward and adjoint Boltzmann transport equations

  6. [11C]PE2I: a highly selective radioligand for PET examination of the dopamine transporter in monkey and human brain

    International Nuclear Information System (INIS)

    Halldin, Christer; Erixon-Lindroth, Nina; Pauli, Stefan; Chou, Yuan-Hwa; Okubo, Yoshiro; Karlsson, Per; Lundkvist, Camilla; Olsson, Hans; Farde, Lars; Guilloteau, Denis; Emond, Patrick

    2003-01-01

    The aim of this study was to explore the potential of a new selective dopamine transporter (DAT) compound as a radioligand for positron emission tomography (PET) examination of DAT in the human brain. The high affinity DAT compound N-(3-iodoprop-2E-enyl)-2β-carbomethoxy-3β-(4-methylphenyl)nortropane (PE2I) was radiolabelled by the O-methylation approach and the binding was characterised by PET in cynomolgus monkeys and a healthy man. Metabolite levels in plasma were measured by gradient high-performance liquid chromatography. O-methylation of the corresponding free acid precursor with [ 11 C]methyl triflate gave high radiochemical yield (80%) and specific radioactivity (55 GBq/μmol). [ 11 C]PE2I binding in cynomolgus monkeys was nine times higher in the striatum than in the cerebellum at peak equilibrium, which appeared 55-65 min after injection. Displacement and pretreatment measurements using unlabelled β-CIT, GBR 12909, cocaine, citalopram and maprotiline confirmed that [ 11 C]PE2I binds selectively to DAT. In a preliminary study in one human subject the radioactivity ratios of the striatum and substantia nigra to the cerebellum were 10 and 1.8, respectively, at peak equilibrium, which appeared at 40-50 min and 20 min, respectively, after injection. The fraction of the total radioactivity in monkey and human plasma representing unchanged [ 11 C]PE2I was 15-20% at 40 min after injection. The present characterisation of binding in monkey and man suggests that [ 11 C]PE2I is a suitable PET radioligand for quantitative regional examination of DAT in man. (orig.)

  7. [{sup 11}C]PE2I: a highly selective radioligand for PET examination of the dopamine transporter in monkey and human brain

    Energy Technology Data Exchange (ETDEWEB)

    Halldin, Christer; Erixon-Lindroth, Nina; Pauli, Stefan; Chou, Yuan-Hwa; Okubo, Yoshiro; Karlsson, Per; Lundkvist, Camilla; Olsson, Hans; Farde, Lars [Karolinska Institutet, Department of Clinical Neuroscience, Psychiatry Section, Karolinska Hospital, 17176, Stockholm (Sweden); Guilloteau, Denis; Emond, Patrick [INSERM U316 Universite Francois Rabelais, Tours (France)

    2003-09-01

    The aim of this study was to explore the potential of a new selective dopamine transporter (DAT) compound as a radioligand for positron emission tomography (PET) examination of DAT in the human brain. The high affinity DAT compound N-(3-iodoprop-2E-enyl)-2{beta}-carbomethoxy-3{beta}-(4-methylphenyl)nortropane (PE2I) was radiolabelled by the O-methylation approach and the binding was characterised by PET in cynomolgus monkeys and a healthy man. Metabolite levels in plasma were measured by gradient high-performance liquid chromatography. O-methylation of the corresponding free acid precursor with [{sup 11}C]methyl triflate gave high radiochemical yield (80%) and specific radioactivity (55 GBq/{mu}mol). [{sup 11}C]PE2I binding in cynomolgus monkeys was nine times higher in the striatum than in the cerebellum at peak equilibrium, which appeared 55-65 min after injection. Displacement and pretreatment measurements using unlabelled {beta}-CIT, GBR 12909, cocaine, citalopram and maprotiline confirmed that [{sup 11}C]PE2I binds selectively to DAT. In a preliminary study in one human subject the radioactivity ratios of the striatum and substantia nigra to the cerebellum were 10 and 1.8, respectively, at peak equilibrium, which appeared at 40-50 min and 20 min, respectively, after injection. The fraction of the total radioactivity in monkey and human plasma representing unchanged [{sup 11}C]PE2I was 15-20% at 40 min after injection. The present characterisation of binding in monkey and man suggests that [{sup 11}C]PE2I is a suitable PET radioligand for quantitative regional examination of DAT in man. (orig.)

  8. Functional characterization of a recombinant sodium-dependent nucleoside transporter with selectivity for pyrimidine nucleosides (cNT1rat) by transient expression in cultured mammalian cells.

    OpenAIRE

    Fang, X; Parkinson, F E; Mowles, D A; Young, J D; Cass, C E

    1996-01-01

    We have demonstrated that monkey kidney (COS-1) cells have a single type of nucleoside transport process, which, because it was equilibrative, sodium-independent and could be inhibited by nitrobenzylthioinosine (NBMPR), was identified as the 'equilibrative sensitive' or 'es' transporter. Using NBMPR or dilazep to inhibit the endogenous nucleoside transport activity, we have transiently expressed a cDNA that encodes an inhibitor-insensitive, concentrative nucleoside transporter protein (cNT1ra...

  9. Expert and novice facilitated modelling

    DEFF Research Database (Denmark)

    Tavella, Elena; Papadopoulos, Thanos

    2015-01-01

    , and empirically supports the claim that facilitation skills can be taught to participants to enable them to self-facilitate workshops. Differences were also found, which led to the introduction of a new dimension—‘internal versus external’ facilitation. The implications of our findings for effective training...

  10. Facilitating post traumatic growth

    Directory of Open Access Journals (Sweden)

    Cox Helen

    2004-07-01

    Full Text Available Abstract Background Whilst negative responses to traumatic injury have been well documented in the literature, there is a small but growing body of work that identifies posttraumatic growth as a salient feature of this experience. We contribute to this discourse by reporting on the experiences of 13 individuals who were traumatically injured, had undergone extensive rehabilitation and were discharged from formal care. All participants were injured through involvement in a motor vehicle accident, with the exception of one, who was injured through falling off the roof of a house. Methods In this qualitative study, we used an audio-taped in-depth interview with each participant as the means of data collection. Interviews were transcribed verbatim and analysed thematically to determine the participants' unique perspectives on the experience of recovery from traumatic injury. In reporting the findings, all participants' were given a pseudonym to assure their anonymity. Results Most participants indicated that their involvement in a traumatic occurrence was a springboard for growth that enabled them to develop new perspectives on life and living. Conclusion There are a number of contributions that health providers may make to the recovery of individuals who have been traumatically injured to assist them to develop new views of vulnerability and strength, make changes in relationships, and facilitate philosophical, physical and spiritual growth.

  11. Magnetic type transportation system

    International Nuclear Information System (INIS)

    Kobama, Masao.

    1981-01-01

    Purpose: To enable automatic transportation of nuclear substances with optional setting for the transportation distance, even for a long distance, facilitating the automation of the transportation and decreasing the space for the installation of a direction converging section of the transporting path. Constitution: A transporting vehicle having a pair of permanent magnets or ferromagnetic bodies mounted with a predetermined gap to each other along the transporting direction is provided in the transporting path including a bent direction change section for transporting specimens such as nuclear materials, and a plurality of driving vehicles having permanent magnets or ferromagnetic bodies for magnetically attracting the transporting vehicle from outside of the transporting path are arranged to the outside of the transporting path. At least one of the driving vehicles is made to run along the transporting direction of the transporting path by a driving mechanism incorporating running section such as an endless chain to drive the transportation vehicle, and the transporting vehicle is successively driven by each of the driving mechanisms. (Kawakami, Y.)

  12. The directionality of the nuclear transport of the influenza A genome is driven by selective exposure of nuclear localization sequences on nucleoprotein

    Directory of Open Access Journals (Sweden)

    Panté Nelly

    2009-06-01

    Full Text Available Abstract Background Early in infection, the genome of the influenza A virus, consisting of eight complexes of RNA and proteins (termed viral ribonucleoproteins; vRNPs, enters the nucleus of infected cells for replication. Incoming vRNPs are imported into the nucleus of infected cells using at least two nuclear localization sequences on nucleoprotein (NP; NLS1 at the N terminus, and NLS2 in the middle of the protein. Progeny vRNP assembly occurs in the nucleus, and later in infection, these are exported from the nucleus to the cytoplasm. Nuclear-exported vRNPs are different from incoming vRNPs in that they are prevented from re-entering the nucleus. Why nuclear-exported vRNPs do not re-enter the nucleus is unknown. Results To test our hypothesis that the exposure of NLSs on the vRNP regulates the directionality of the nuclear transport of the influenza vRNPs, we immunolabeled the two NLSs of NP (NLS1 and NLS2 and analyzed their surface accessibility in cells infected with the influenza A virus. We found that the NLS1 epitope on NP was exposed throughout the infected cells, but the NLS2 epitope on NP was only exposed in the nucleus of the infected cells. Addition of the nuclear export inhibitor leptomycin B further revealed that NLS1 is no longer exposed in cytoplasmic NP and vRNPs that have already undergone nuclear export. Similar immunolabeling studies in the presence of leptomycin B and with cells transfected with the cDNA of NP revealed that the NLS1 on NP is hidden in nuclear exported-NP. Conclusion NLS1 mediates the nuclear import of newly-synthesized NP and incoming vRNPs. This NLS becomes hidden on nuclear-exported NP and nuclear-exported vRNPs. Thus the selective exposure of the NLS1 constitutes a critical mechanism to regulate the directionality of the nuclear transport of vRNPs during the influenza A viral life cycle.

  13. Transportation Consumer Education Curriculum Guide.

    Science.gov (United States)

    Finn, Peter; And Others

    Materials in this curriculum guide represent a selection of the major transportation consumer topics and ideas and are designed to set the stage for more intensive transportation consumer education curriculum development and teacher efforts. (Eleven manuals covering the four transportation topics of public transportation, transportation and the…

  14. The FORATOM Transport Working Group

    International Nuclear Information System (INIS)

    Lehmann, P.

    2000-01-01

    Based in Brussels, the European atomic forum FORATOM is the trade association of the European nuclear industry which was established in the early 1960s to promote nuclear power and to facilitate relations with the European institutions. One of the main mechanisms which FORATOM uses, in its dealings with the European Commission and other international organisations, is the involvement of several working groups bringing together groups of experts drawn from the industrial companies in order to identify the issues and to develop the widest possible common views on which the industry must express its representative, substantial and deliverable opinion. The Transport Working Group (TWG) has the objective of dealing with transport of radioactive material, especially nuclear materials. The TWG usually meets three times a year in Brussels or another selected location. It has strong links with the European Commission which are evidenced by the fact that it officially represents the European nuclear industry, with the status of observer, at the meetings of the Standing Working Group on Safe Transport of Radioactive Material which was set up in 1982, upon a request of the European Parliament, to advise the European Commission in the field of safe transport of radioactive materials. The Standing Working Group (SWG) assists the European Union's Member States in the revision process of IAEA recommendations and helps a correct and harmonious application of these recommendations within the European Union. In previous years, the Standing Working Group has proposed over 40 different studies, financed by the European Commission, on important transport issues. The FORATOM TWG encourages its member organisations to participate in studies proposed by the Commission and has been cooperating for many years with the Commission in the field of many studies aimed to improve the application of transport regulations. The need to maintain the safe and reliable operation of plants that generate

  15. The disc method. A new method for selecting facilitations in flocculating sludge to be dewatered in centrifuges; Metodo de disco. Un nuevo metodo para la seleccion de floculantes en la floculacion de lodos a deshidratar en centrifugas

    Energy Technology Data Exchange (ETDEWEB)

    Canga Rodriguez, J.; Gutierrez Lavin, A.

    2002-07-01

    An experimental protocol was designed at a laboratory scale, in view of achieving the selection with different poly electrolytes related to the chemical conditioning (flocculation) of sewage sludge before dewatering it in a drying centrifuge. The method is based on a new parameter of quality of the formed floc, which measures its compaction when is submitted to a fix external strength. Some experimental tests have been introduced, whose results are numbers, avoiding all subjective aspects related to direct observation of flocs. (Author) 8 refs.

  16. Occurrence and transport of diazinon in the Sacramento River, California, and selected tributaries during three winter storms, January-February 2000

    Science.gov (United States)

    Dileanis, Peter D.; Bennett, Kevin P.; Domagalski, Joseph L.

    2002-01-01

    The organophosphate pesticide diazinon is applied as a dormant orchard spray in the Sacramento Valley, California, during the winter when the area receives a majority of its annual rainfall. Dormant spray pesticides, thus, have the potential to wash off the areas of application and migrate with storm runoff to streams in the Sacramento River Basin. Previous monitoring studies have shown that rain and associated runoff from winter storms plays an important role in the transport of diazinon from point of application to the Sacramento River and tributaries. Between January 30 and February 25, 2000, diazinon concentrations in the Sacramento River and selected tributaries were monitored on 5 consecutive days during each of three winter storms that moved through the Sacramento Valley after diazinon had been applied to orchards in the basin. Water samples were collected at 17 sites chosen to represent the effect of upstream land use at local and regional scales. Most samples were analyzed using an enzyme-linked immunosorbent assay (ELISA). Analysis by gas chromatography with electron capture detector and thermionic specific detector (GC/ECD/TSD) and gas chromatography with mass spectrometry (GC/MS) was done on split replicates from over 30 percent of the samples to confirm ELISA results and to provide lower analytical reporting limits at selected sites [30 ng/L (nanogram per liter) for ELISA, 20 ng/L for GC/ECD/TSD, and 2 ng/L for GC/MS]. Concentrations determined from ELISA analyses were consistently higher than concentrations for split samples analyzed by gas chromatography methods. Because of bias between diazinon concentrations using ELISA and gas chromatography methods, results from ELISA analyses were not compared to water-quality criteria. Load calculations using the ELISA analyses are similarly biased. Because the bias was consistent, however, the ELISA data is useful in site-to-site comparisons used to rank the relative levels and contributions of diazinon from

  17. Resveratrol Inhibits Porcine Intestinal Glucose and Alanine Transport: Potential Roles of Na+/K+-ATPase Activity, Protein Kinase A, AMP-Activated Protein Kinase and the Association of Selected Nutrient Transport Proteins with Detergent Resistant Membranes

    Directory of Open Access Journals (Sweden)

    Stefanie Klinger

    2018-03-01

    Full Text Available Background: Beneficial effects of Resveratrol (RSV have been demonstrated, including effects on transporters and channels. However, little is known about how RSV influences intestinal transport. The aim of this study was to further characterize the effects of RSV on intestinal transport and the respective mechanisms. Methods: Porcine jejunum and ileum were incubated with RSV (300 µM, 30 min in Ussing chambers (functional studies and tissue bathes (detection of protein expression, phosphorylation, association with detergent resistant membranes (DRMs. Results: RSV reduced alanine and glucose-induced short circuit currents (ΔIsc and influenced forskolin-induced ΔIsc. The phosphorylation of sodium–glucose-linked transporter 1 (SGLT1, AMP-activated protein kinase (AMPK, protein kinase A substrates (PKA-S and liver kinase B1 (LKB1 increased but a causative relation to the inhibitory effects could not directly be established. The DRM association of SGLT1, peptide transporter 1 (PEPT1 and (phosphorylated Na+/H+-exchanger 3 (NHE3 did not change. Conclusion: RSV influences the intestinal transport of glucose, alanine and chloride and is likely to affect other transport processes. As the effects of protein kinase activation vary between the intestinal localizations, it would appear that increasing cyclic adenosine monophosphate (cAMP levels are part of the mechanism. Nonetheless, the physiological responses depend on cell type-specific structures.

  18. Ligand binding analyses of the putative peptide transporter YjdL from E. coli display a significant selectivity towards dipeptides

    DEFF Research Database (Denmark)

    Ernst, Heidi Asschenfeldt; Pham, Antony; Hald, Helle

    2009-01-01

    Proton-dependent oligopeptide transporters (POTs) are secondary active transporters that couple the inwards translocation of di- and tripeptides to inwards proton translocation. Escherichia coli contains four genes encoding the putative POT proteins YhiP, YdgR, YjdL and YbgH. We have over-express...

  19. Fluoxetine Facilitates Fear Extinction Through Amygdala Endocannabinoids

    Science.gov (United States)

    Gunduz-Cinar, Ozge; Flynn, Shaun; Brockway, Emma; Kaugars, Katherine; Baldi, Rita; Ramikie, Teniel S; Cinar, Resat; Kunos, George; Patel, Sachin; Holmes, Andrew

    2016-01-01

    Pharmacologically elevating brain endocannabinoids (eCBs) share anxiolytic and fear extinction-facilitating properties with classical therapeutics, including the selective serotonin reuptake inhibitor, fluoxetine. There are also known functional interactions between the eCB and serotonin systems and preliminary evidence that antidepressants cause alterations in brain eCBs. However, the potential role of eCBs in mediating the facilitatory effects of fluoxetine on fear extinction has not been established. Here, to test for a possible mechanistic contribution of eCBs to fluoxetine's proextinction effects, we integrated biochemical, electrophysiological, pharmacological, and behavioral techniques, using the extinction-impaired 129S1/Sv1mJ mouse strain. Chronic fluoxetine treatment produced a significant and selective increase in levels of anandamide in the BLA, and an associated decrease in activity of the anandamide-catabolizing enzyme, fatty acid amide hydrolase. Slice electrophysiological recordings showed that fluoxetine-induced increases in anandamide were associated with the amplification of eCB-mediated tonic constraint of inhibitory, but not excitatory, transmission in the BLA. Behaviorally, chronic fluoxetine facilitated extinction retrieval in a manner that was prevented by systemic or BLA-specific blockade of CB1 receptors. In contrast to fluoxetine, citalopram treatment did not increase BLA eCBs or facilitate extinction. Taken together, these findings reveal a novel, obligatory role for amygdala eCBs in the proextinction effects of a major pharmacotherapy for trauma- and stressor-related disorders and anxiety disorders. PMID:26514583

  20. A software architecture for a transportation control tower

    NARCIS (Netherlands)

    Baumgrass, A.; Dijkman, R.M.; Grefen, P.W.P.J.; Pourmirza, S.; Völzer, H.; Weske, M.H.

    2014-01-01

    A Transportation Control Tower is a software application that facilitates transportation planners with easily monitoring and dispatching transportation resources. This paper presents a software architecture for such an application. It focuses in particular on the novel aspects of the software

  1. U.S. and Texas international trade and transportation.

    Science.gov (United States)

    2011-07-01

    This report, funded by the Southwest Region University Transportation Center, examines various : aspects of international trade, transportation, and foreign practices implemented facilitate and fund : transport-related infrastructure. The report is c...

  2. Animal transportation networks

    Science.gov (United States)

    Perna, Andrea; Latty, Tanya

    2014-01-01

    Many group-living animals construct transportation networks of trails, galleries and burrows by modifying the environment to facilitate faster, safer or more efficient movement. Animal transportation networks can have direct influences on the fitness of individuals, whereas the shape and structure of transportation networks can influence community dynamics by facilitating contacts between different individuals and species. In this review, we discuss three key areas in the study of animal transportation networks: the topological properties of networks, network morphogenesis and growth, and the behaviour of network users. We present a brief primer on elements of network theory, and then discuss the different ways in which animal groups deal with the fundamental trade-off between the competing network properties of travel efficiency, robustness and infrastructure cost. We consider how the behaviour of network users can impact network efficiency, and call for studies that integrate both network topology and user behaviour. We finish with a prospectus for future research. PMID:25165598

  3. Guidebook : using public transportation to facilitate last mile package delivery.

    Science.gov (United States)

    2017-03-01

    This guidebook is designed to inform rural transit operators of how to implement a package delivery service using information and input gathered from the state-of-the practice scan, the fact-finding questionnaire, and stakeholder workshops. The guide...

  4. Using Spoken Language to Facilitate Military Transportation Planning

    National Research Council Canada - National Science Library

    Bates, Madeleine; Ellard, Dan; Peterson, Pat; Shaked, Varda

    1991-01-01

    .... In an effort to demonstrate the relevance of SIS technology to real-world military applications, BBN has undertaken the task of providing a spoken language interface to DART, a system for military...

  5. Insulin facilitates transport of macromolecules and nutrients to muscles

    DEFF Research Database (Denmark)

    Christensen, N J; Hilsted, J

    1993-01-01

    We previously showed that intravenous insulin increased plasma noradrenaline during euglycemia and without concomitant changes in plasma adrenaline. Insulin decreased plasma volume and increased the fractional escape rate of albumin from plasma. In normal subjects, oral glucose increased heart ra...... the blood to the extracellular space after food intake. This process may be greatly disturbed in insulin-dependent diabetic patients....

  6. Nucleocytoplasmic Transport: A Paradigm for Molecular Logistics in Artificial Systems.

    Science.gov (United States)

    Vujica, Suncica; Zelmer, Christina; Panatala, Radhakrishnan; Lim, Roderick Y H

    2016-01-01

    Artificial organelles, molecular factories and nanoreactors are membrane-bound systems envisaged to exhibit cell-like functionality. These constitute liposomes, polymersomes or hybrid lipo-polymersomes that display different membrane-spanning channels and/or enclose molecular modules. To achieve more complex functionality, an artificial organelle should ideally sustain a continuous influx of essential macromolecular modules (i.e. cargoes) and metabolites against an outflow of reaction products. This would benefit from the incorporation of selective nanopores as well as specific trafficking factors that facilitate cargo selectivity, translocation efficiency, and directionality. Towards this goal, we describe how proteinaceous cargoes are transported between the nucleus and cytoplasm by nuclear pore complexes and the biological trafficking machinery in living cells (i.e. nucleocytoplasmic transport). On this basis, we discuss how biomimetic control may be implemented to selectively import, compartmentalize and accumulate diverse macromolecular modules against concentration gradients in artificial organelles.

  7. Learning to Facilitate (Online) Meetings

    DEFF Research Database (Denmark)

    Reimann, Peter; Bull, Susan; Vatrapu, Ravi

    2013-01-01

    We describe an approach to teaching collaboration skills directly by building on competences for meeting facilitation. (Online) meetings provide a rich arena to practice collaboration since they can serve multiple purposes: learning, problem solving, decision making, idea generation and advancement...

  8. Facilitative root interactions in intercrops

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, H.; Jensen, E.S.

    2005-01-01

    of root architecture, exudation of growth stimulating substances, and biofumigation. Facilitative root interactions are most likely to be of importance in nutrient poor soils and in low-input agroecosystems due to critical interspecific competition for plant growth factors. However, studies from more...... nitrogen transfer between legumes and non-leguminous plants, exploitation of the soil via mycorrhizal fungi and soil-plant processes which alter the mobilisation of plant growth resources such as through exudation of amino acids, extra-cellular enzymes, acidification, competition-induced modification......Facilitation takes place when plants ameliorate the environment of their neighbours, and increase their growth and survival. Facilitation occurs in natural ecosystems as well as in agroecosystems. We discuss examples of facilitative root interactions in intercropped agroecosystems; including...

  9. On novice facilitators doing research

    DEFF Research Database (Denmark)

    Tavella, Elena

    2018-01-01

    Opportunities for novices to facilitate Problem Structuring Methods (PSMs) workshops are limited, especially because of a lack of access to real-world interventions and confidence in their capabilities. Novices are usually young academics building their careers through publishing. Publishing...... is challenging if facilitation and opportunities for data collection are limited. To address this challenge, this paper suggests autoethnography as a framework for addressing difficulties that novices face in conducting research and publishing on PSMs. This suggestion grows out of a literature study...

  10. Facilitation Skills for Library Professionals

    OpenAIRE

    O'Shea, Anne; Matheson, Laura

    2010-01-01

    Session summary: Brainstorming, problem-solving, team-building and group communication – all of these things can be made easier through facilitation! Come to this fun, interactive workshop to learn techniques and exercises to boost your group meetings. Taught by two information professionals with formal facilitation training and experience, this workshop will give you theory, hands-on practice time and feedback. What participants will learn: Participants will learn techniques to he...

  11. Nanoparticle Facilitated Extracellular Electron Transfer in Microbial Fuel Cells

    Science.gov (United States)

    2014-10-13

    harvestingelectrical power directly from waste and renewable biomass and thus represent a promising technology for sustainable energy production.1−5 Central...cell membrane (Figure 3e), serving as a porous semiconducting “ shell ” to facilitate the charge transport at bacteria/electrode or bacteria/bacteria

  12. Sex-Differences in Renal Expression of Selected Transporters and Transcription Factors in Lean and Obese Zucker Spontaneously Hypertensive Fatty Rats

    Directory of Open Access Journals (Sweden)

    Andrea Babelova

    2015-01-01

    Full Text Available The aim of this study was to identify sex-dependent expression of renal transporter mRNA in lean and obese Zucker spontaneously hypertensive fatty (ZSF1 rats and to investigate the interaction of the most altered transporter, organic anion transporter 2 (Oat2, with diabetes-relevant metabolites and drugs. Higher incidence of glomerulosclerosis, tubulointerstitial fibrosis, and protein casts in Bowman’s space and tubular lumen was detected by PAS staining in obese male compared to female ZSF1 rats. Real-time PCR on RNA isolated from kidney cortex revealed that Sglt1-2, Oat1-3, and Oct1 were higher expressed in kidneys of lean females. Oct2 and Mrp2 were higher expressed in obese males. Renal mRNA levels of transporters were reduced with diabetic nephropathy in females and the expression of transcription factors Hnf1β and Hnf4α in both sexes. The highest difference between lean and obese ZSF1 rats was found for Oat2. Therefore, we have tested the interaction of human OAT2 with various substances using tritium-labeled cGMP. Human OAT2 showed no interaction with diabetes-related metabolites, diabetic drugs, and ACE-inhibitors. However, OAT2-dependent uptake of cGMP was inhibited by furosemide. The strongly decreased expression of Oat2 and other transporters in female diabetic ZSF1 rats could possibly impair renal drug excretion, for example, of furosemide.

  13. Tri-partite complex for axonal transport drug delivery achieves pharmacological effect

    Directory of Open Access Journals (Sweden)

    Frederickson Martyn

    2010-01-01

    Full Text Available Abstract Background Targeted delivery of pharmaceutical agents into selected populations of CNS (Central Nervous System neurons is an extremely compelling goal. Currently, systemic methods are generally used for delivery of pain medications, anti-virals for treatment of dermatomal infections, anti-spasmodics, and neuroprotectants. Systemic side effects or undesirable effects on parts of the CNS that are not involved in the pathology limit efficacy and limit clinical utility for many classes of pharmaceuticals. Axonal transport from the periphery offers a possible selective route, but there has been little progress towards design of agents that can accomplish targeted delivery via this intraneural route. To achieve this goal, we developed a tripartite molecular construction concept involving an axonal transport facilitator molecule, a polymer linker, and a large number of drug molecules conjugated to the linker, then sought to evaluate its neurobiology and pharmacological behavior. Results We developed chemical synthesis methodologies for assembling these tripartite complexes using a variety of axonal transport facilitators including nerve growth factor, wheat germ agglutinin, and synthetic facilitators derived from phage display work. Loading of up to 100 drug molecules per complex was achieved. Conjugation methods were used that allowed the drugs to be released in active form inside the cell body after transport. Intramuscular and intradermal injection proved effective for introducing pharmacologically effective doses into selected populations of CNS neurons. Pharmacological efficacy with gabapentin in a paw withdrawal latency model revealed a ten fold increase in half life and a 300 fold decrease in necessary dose relative to systemic administration for gabapentin when the drug was delivered by axonal transport using the tripartite vehicle. Conclusion Specific targeting of selected subpopulations of CNS neurons for drug delivery by axonal

  14. An incoherent feedforward loop facilitates adaptive tuning of gene expression.

    Science.gov (United States)

    Hong, Jungeui; Brandt, Nathan; Abdul-Rahman, Farah; Yang, Ally; Hughes, Tim; Gresham, David

    2018-04-05

    We studied adaptive evolution of gene expression using long-term experimental evolution of Saccharomyces cerevisiae in ammonium-limited chemostats. We found repeated selection for non-synonymous variation in the DNA binding domain of the transcriptional activator, GAT1, which functions with the repressor, DAL80 in an incoherent type-1 feedforward loop (I1-FFL) to control expression of the high affinity ammonium transporter gene, MEP2. Missense mutations in the DNA binding domain of GAT1 reduce its binding to the GATAA consensus sequence. However, we show experimentally, and using mathematical modeling, that decreases in GAT1 binding result in increased expression of MEP2 as a consequence of properties of I1-FFLs. Our results show that I1-FFLs, one of the most commonly occurring network motifs in transcriptional networks, can facilitate adaptive tuning of gene expression through modulation of transcription factor binding affinities. Our findings highlight the importance of gene regulatory architectures in the evolution of gene expression. © 2018, Hong et al.

  15. Interventions to Encourage and Facilitate Greener Industrial Chemicals Selection

    OpenAIRE

    Faulkner, David

    2017-01-01

    Despite their ubiquity in modern life, industrial chemicals are poorly regulated in the United States. Statutory law defines industrial chemicals as chemicals that are not foods, drugs, cosmetics, nor pesticides, but may be used in consumer products, and this distinction places them under the purview of the Toxic Substances Control Act (TSCA), which received a substantial update when the US congress passed a revision of the act in 2016. The revised law, the Frank R. Lautenberg Chemical Safety...

  16. The expression of glycerol facilitators from various yeast species improves growth on glycerol of Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Mathias Klein

    2016-12-01

    Full Text Available Glycerol is an abundant by-product during biodiesel production and additionally has several assets compared to sugars when used as a carbon source for growing microorganisms in the context of biotechnological applications. However, most strains of the platform production organism Saccharomyces cerevisiae grow poorly in synthetic glycerol medium. It has been hypothesized that the uptake of glycerol could be a major bottleneck for the utilization of glycerol in S. cerevisiae. This species exclusively relies on an active transport system for glycerol uptake. This work demonstrates that the expression of predicted glycerol facilitators (Fps1 homologues from superior glycerol-utilizing yeast species such as Pachysolen tannophilus, Komagataella pastoris, Yarrowia lipolytica and Cyberlindnera jadinii significantly improves the growth performance on glycerol of the previously selected glycerol-consuming S. cerevisiae wild-type strain (CBS 6412-13A. The maximum specific growth rate increased from 0.13 up to 0.18 h−1 and a biomass yield coefficient of 0.56 gDW/gglycerol was observed. These results pave the way for exploiting the assets of glycerol in the production of fuels, chemicals and pharmaceuticals based on baker's yeast. Keywords: Yeast, Saccharomyces cerevisiae, Glycerol, Transport, Glycerol facilitator, Fps1, Stl1

  17. Beta-Sulfonamido Functionalized Aspartate Analogs as Excitatory Amino Acid Transporter Inhibitors: Distinct Subtype-Selectivity Profiles Arising from Subtle Structural Differences

    DEFF Research Database (Denmark)

    Hansen, Jacob Christian; Bjørn-Yoshimoto, Walden Emil; Bisballe, Niels

    2016-01-01

    In this study inspired by previous work on 3-substituted Asp analogues, we designed and synthesized a total of 32 β-sulfonamide Asp analogues and characterized their pharmacological properties at the excitatory amino acid transporter subtypes EAAT1, EAAT2, and EAAT3. In addition to several potent...

  18. Bibliography for acid-rock drainage and selected acid-mine drainage issues related to acid-rock drainage from transportation activities

    Science.gov (United States)

    Bradley, Michael W.; Worland, Scott C.

    2015-01-01

    Acid-rock drainage occurs through the interaction of rainfall on pyrite-bearing formations. When pyrite (FeS2) is exposed to oxygen and water in mine workings or roadcuts, the mineral decomposes and sulfur may react to form sulfuric acid, which often results in environmental problems and potential damage to the transportation infrastructure. The accelerated oxidation of pyrite and other sulfidic minerals generates low pH water with potentially high concentrations of trace metals. Much attention has been given to contamination arising from acid mine drainage, but studies related to acid-rock drainage from road construction are relatively limited. The U.S. Geological Survey, in cooperation with the Tennessee Department of Transportation, is conducting an investigation to evaluate the occurrence and processes controlling acid-rock drainage and contaminant transport from roadcuts in Tennessee. The basic components of acid-rock drainage resulting from transportation activities are described and a bibliography, organized by relevant categories (remediation, geochemical, microbial, biological impact, and secondary mineralization) is presented.

  19. Theoretical and experimental evaluation of waste transport in selected rocks: 1977 annual report of LBL Contract No. 45901AK. Waste Isolation Safety Assessment Program: collection and generation of transport data

    International Nuclear Information System (INIS)

    Apps, J.A.; Benson, L.V.; Lucas, J.; Mathur, A.K.; Tsao, L.

    1977-09-01

    During fiscal year 1977, the following subtasks were performed. (1) Thermodynamic data were tabulated for those aqueous complexes and solid phases of plutonium, neptunium, americium, and curium likely to form in the environment. (2) Eh-pH diagrams were computed and drafted for plutonium, neptunium, americium and curium at 25 0 C and one atmosphere. (3) The literature on distribution coefficients of plutonium, neptunium, americium, and curium was reviewed. (4) Preliminary considerations were determined for an experimental method of measuring radionuclide transport in water-saturated rocks. (5) The transport mechanisms of radionuclides in water-saturated rocks were reviewed. (6) A computer simulation was attempted of mass transfer involving actinides in water-saturated rocks. Progress in these tasks is reported. Subtasks 1, 2, 3, and 4 are complete. The progress made in subtask 5 is represented by an initial theoretical survey to define the conditions needed to characterize the transport of radionuclides in rocks. Subtask 6 has begun but is not complete

  20. Cognitive implications of facilitating echoic persistence.

    Science.gov (United States)

    Baldwin, Carryl L

    2007-06-01

    Seventeen participants performed a tone-pattern-matching task at different presentation levels while concurrently engaged in a simulated-driving task. Presentation levels of 60, 65, and 70 dBC (SPL) were combined factorially with tone-matching delays of 2, 3, and 4 sec. Intensity had no effect on performance in single-task conditions and short-delay conditions. However, when the participants were engaged concurrently in the driving task, a significant interaction between presentation level and delay was observed. In the longest delay condition, the participants performed the tone-pattern-matching task more efficiently (more quickly and without additional errors) as presentation intensity increased. These findings demonstrate the interaction between sensory and cognitive processes and point to a direct-intensity relationship where intensity affects the persistence of echoic memory. Implications for facilitating auditory processing and improving auditory interfaces in complex systems (i.e., transportation environments), particularly for older and hearing-impaired listeners, are discussed.

  1. The orotate transporter oroP from Lactococcus lactis can be used both as a very efficient, food-grade selection and counter-selection marker for strain construction in many different organisms

    DEFF Research Database (Denmark)

    Defoor, Els Marie Celine; Martinussen, Jan

    frame oroP on pDBORO necessary for the uptake of orotate was identified. A number of industrial important strains like Lactococcus lactis, Bacillus subtilus, and Bacillus licheniformis have been shown to be unable to metabolize orotate. If the oroP gene was introduced into these strains they acquired...... the ability to utilize orotate. If the strains had a pyrimidine requirement, the oroP gene could function as a selectable marker when growing in the presence of orotate as sole pyrimidine source. In an otherwise resistant strain, oroP was shown to sensitize the strain towards the analog 5-Fluoroorotate....... It was shown that strains who have lost the oroP gene could easily be selected in the presence of 5-Fluoroorotate, thus being an efficient counter-selection marker. pyrimidine-requiring strain (pyr B, C or D) orotate negative Counter-selection marker: wild-type strain! Fluoro-orotate resistant Functional...

  2. ANALYISIS OF TRANSPORTATION SYSTEMS AND TRANSPORTATION POLICIES IN TURKEY

    OpenAIRE

    Ali Payıdar AKGÜNGÖR; Abdulmuttalip DEMİREL

    2004-01-01

    Transportation systems have to be considered and analysed as a whole while transportation demand, becoming as a natural outcome of socioeconomic and socio-cultural structure, is being evaluated. It is desired that transportation system, which will be selected for both passenger and freight transport, should be rapid, economic, safe, causing least harm to environment and appropriate for the conditions of a country. However, it is difficult for a transportation system to have all these properti...

  3. Facilitation of learning: part 1.

    Science.gov (United States)

    Warburton, Tyler; Trish, Houghton; Barry, Debbie

    2016-04-06

    This article, the fourth in a series of 11, discusses the context for the facilitation of learning. It outlines the main principles and theories for understanding the process of learning, including examples which link these concepts to practice. The practical aspects of using these theories in a practice setting will be discussed in the fifth article of this series. Together, these two articles will provide mentors and practice teachers with knowledge of the learning process, which will enable them to meet the second domain of the Nursing and Midwifery Council's Standards to Support Learning and Assessment in Practice on facilitation of learning.

  4. A Near-real-time Data Transport System for Selected Stations in the Magnetometer Array for Cusp and Cleft Studies (MACCS)

    Science.gov (United States)

    Engebretson, M. J.; Valentic, T. A.; Stehle, R. H.; Hughes, W. J.

    2004-05-01

    The Magnetometer Array for Cusp and Cleft Studies (MACCS) is a two-dimensional array of eight fluxgate magnetometers that was established in 1992-1993 in the Eastern Canadian Arctic from 75° to over 80° MLAT to study electrodynamic interactions between the solar wind and Earth's magnetosphere and high-latitude ionosphere. A ninth site in Nain, Labrador, extends coverage down to 66° between existing Canadian and Greenland stations. Originally designed as part of NSF's GEM (Geospace Environment Modeling) Program, MACCS has contributed to the study of transients and waves at the magnetospheric boundary and in the near-cusp region as well as to large, cooperative, studies of ionospheric convection and substorm processes. Because of the limitations of existing telephone lines to each site, it has not been possible to economically access MACCS data promptly; instead, each month's collected data is recorded and mailed to the U.S. for processing and eventual posting on a publicly-accessible web site, http://space.augsburg.edu/space. As part of its recently renewed funding, NSF has supported the development of a near-real-time data transport system using the Iridium satellite network, which will be implemented at two MACCS sites in summer 2004. At the core of the new MACCS communications system is the Data Transport Network, software developed with NSF-ITR funding to automate the transfer of scientific data from remote field stations over unreliable, bandwidth-constrained network connections. The system utilizes a store-and-forward architecture based on sending data files as attachments to Usenet messages. This scheme not only isolates the instruments from network outages, but also provides a consistent framework for organizing and accessing multiple data feeds. Client programs are able to subscribe to data feeds to perform tasks such as system health monitoring, data processing, web page updates and e-mail alerts. The MACCS sites will employ the Data Transport Network

  5. Approach for delineation of contributing areas and zones of transport to selected public-supply wells using a regional ground-water flow model, Palm Beach County, Florida

    Science.gov (United States)

    Renken, R.A.; Patterson, R.D.; Orzol, L.L.; Dixon, Joann

    2001-01-01

    Rapid urban development and population growth in Palm Beach County, Florida, have been accompanied with the need for additional freshwater withdrawals from the surficial aquifer system. To maintain water quality, County officials protect capture areas and determine zones of transport of municipal supply wells. A multistep process was used to help automate the delineation of wellhead protection areas. A modular ground-water flow model (MODFLOW) Telescopic Mesh Refinement program (MODTMR) was used to construct an embedded flow model and combined with particle tracking to delineate zones of transport to supply wells; model output was coupled with a geographic information system. An embedded flow MODFLOW model was constructed using input and output file data from a preexisting three-dimensional, calibrated model of the surficial aquifer system. Three graphical user interfaces for use with the geographic information software, ArcView, were developed to enhance the telescopic mesh refinement process. These interfaces include AvMODTMR for use with MODTMR; AvHDRD to build MODFLOW river and drain input files from dynamically segmented linear (canals) data sets; and AvWELL Refiner, an interface designed to examine and convert well coverage spatial data layers to a MODFLOW Well package input file. MODPATH (the U.S. Geological Survey particle-tracking postprocessing program) and MODTOOLS (the set of U.S. Geological Survey computer programs to translate MODFLOW and MODPATH output to a geographic information system) were used to map zones of transport. A steady-state, five-layer model of the Boca Raton area was created using the telescopic mesh refinement process and calibrated to average conditions during January 1989 to June 1990. A sensitivity analysis of various model parameters indicates that the model is most sensitive to changes in recharge rates, hydraulic conductivity for layer 1, and leakance for layers 3 and 4 (Biscayne aquifer). Recharge (58 percent); river (canal

  6. Analysis of correlations between the placental expression of glucose transporters GLUT-1, GLUT-4 and GLUT-9 and selected maternal and fetal parameters in pregnancies complicated by diabetes mellitus.

    Science.gov (United States)

    Stanirowski, Paweł Jan; Szukiewicz, Dariusz; Pyzlak, Michał; Abdalla, Nabil; Sawicki, Włodzimierz; Cendrowski, Krzysztof

    2017-10-16

    The aim of the study was to analyze the correlations between the expression of glucose transporters GLUT-1, GLUT-4, and GLUT-9 in human term placenta and selected maternal and fetal parameters in pregnancies complicated by diabetes mellitus (DM). Placental samples were obtained from healthy control (n = 25) and diabetic pregnancies, including diet-controlled gestational diabetes mellitus (GDMG1) (n = 16), insulin-controlled gestational diabetes mellitus (GDMG2) (n = 6), and pregestational DM (PGDM) (n = 6). Computer-assisted quantitative morphometry of stained placental sections was performed to determine the expression of selected glucose transporter proteins. For the purposes of correlation analysis, the following parameters were selected: type of diabetes, gestational age, maternal prepregnancy body mass index (BMI), gestational weight gain, third trimester glycated hemoglobin concentration, placental weight, fetal birth weight (FBW) as well as ultrasonographic indicators of fetal adiposity, including subscapular (SSFM), abdominal (AFM), and midthigh (MTFM) fat mass measurements. In the PGDM group, the analysis demonstrated positive correlations between the placental expression of GLUT-1, GLUT-4, and GLUT-9 and FBW, AFM, and SSFM measurements (p diabetes and FBW were significantly associated with GLUTs expression (p < .001). In addition, maternal prepregnancy BMI significantly contributed to GLUT-1 expression (p < .001). The study results revealed that placental expression of GLUT-1, GLUT-4, and GLUT-9 may be involved in the intensification of the fetal growth in pregnancies complicated by GDM/PGDM.

  7. Transport of radioactive materials

    International Nuclear Information System (INIS)

    1991-07-01

    The purpose of this Norm is to establish, relating to the TRANSPORT OF RADIOACTIVE MATERIALS, safety and radiological protection requirements to ensure an adequate control level of the eventual exposure of persons, properties and environment to the ionizing radiation comprising: specifications on radioactive materials for transport; package type selection; specification of the package design and acceptance test requirements; arrangements relating to the transport itself; administrative requirements and responsibilities. (author)

  8. The Relationships between Human Fatigue and Public Health: A Brief Commentary on Selected Papers from the 9th International Conference on Managing Fatigue in Transportation, Resources and Health

    OpenAIRE

    Charli Sargent; Paul Roberts; Drew Dawson; Sally Ferguson; Lynn Meuleners; Libby Brook; Gregory D. Roach

    2016-01-01

    The 9th International Conference on Managing Fatigue in Transportation, Resources and Health was held in Fremantle, Western Australia in March 2015. The purpose of the conferences in this series is to provide a forum for industry representatives, regulators, and scientists to discuss recent advances in the field of fatigue research. We have produced a Special Issue of the International Journal of Environmental Research and Public Health based on papers from the conference that were focused on...

  9. Facilitation of Mourning During Childhood.

    Science.gov (United States)

    Kliman, Gilbert; And Others

    This paper discusses case studies of children psychologically disturbed by the death of parents or siblings. Illustrations of mourning facilitation were mainly gathered from 16 orphaned children, ages 3-14. Some techniques used in helping children mourn include: discussing physical details of the illness, discussing previous deaths of animals and…

  10. Brug af mindfulness til facilitering

    DEFF Research Database (Denmark)

    Adriansen, Hanne Kirstine; Krohn, Simon

    2011-01-01

    Gennem de senere år er mindfulness gået fra udelukkende at være en eksistentiel praksis til også at være en behandlingsform og senest til også at blive brugt som et praktisk redskab i erhvervslivet. Denne artikel viser, at mindfulness også kan anvendes i forbindelse med facilitering. Facilitering...... er et værktøj, som bruges i arbejdslivet fx til møder og konferencer, hvor en gruppe mennesker er samlet for at lære eller udrette noget sammen. Det nye ved at kombinere mindfulness med facilitering er, at fokus hermed ændres fra individet, som er centrum for den eksistentielle fordybelse eller det...... terapeutiske forløb, til gruppen, som er udgangspunktet i facilitering. Artiklen viser, hvordan mindfulness konkret kan bruges på gruppeniveau og diskuterer samtidig hvilke problemer, der kan være forbundet hermed. Baseret på vores egne erfaringer, diskuterer vi, hvordan mindfulness kan påvirke en gruppes...

  11. Facilitating Conversations about Managerial Identities

    DEFF Research Database (Denmark)

    Madsen, Mona Toft

    -based organization in the engineering consulting sector b) a reflection meeting, where the same three managers were gathered, and conversations were facilitated based on identity work in the context of earlier interviews. More specifically, three themes were discussed; flat organizational structure, tensions between...

  12. Análise do impacto nos custos de transporte de um modelo de seleção de fornecedores baseado em variáveis socioambientais e de competitividade Suppliers selection model and its transportation cost impacts

    Directory of Open Access Journals (Sweden)

    Breno Barros Telles do Carmo

    2011-09-01

    Full Text Available Observa-se uma demanda mundial crescente por energias ditas renováveis. Dentre essas energias, encontra-se o biodiesel, derivado de biomassa renovável. Porém, para que essa cadeia seja competitiva, deve satisfazer alguns critérios de competitividade. Existe também a possibilidade de exportação desse combustível, porém é necessário seguirem-se algumas diretrizes que estão sendo elaboradas para certificação da cadeia de valor dos biocombustíveis, baseada em critérios de sustentabilidade. Assim, o presente artigo tem por objetivo apresentar um modelo de seleção de fornecedores para as usinas de biodiesel, levando em consideração os critérios de certificação e competitividade identificados na cadeia. Foi utilizada a metodologia Smarter para a realização desse modelo. Ele foi agregado em conjunto com um modelo de otimização de transporte para a minimização dos custos envolvidos. Observou-se que o modelo apresenta aumento no custo de transporte, se forem levadas em consideração as imposições de selo social do governo federal.Nowadays, there is a world demand for renewable energies. These kinds of energy must be sustainable to be considered renewable. The consumption of diesel has increased and so has the emission of greenhouse gases. Bio-diesel is an alternative to reduce this kind of emission. But, when the matter is bio-diesel, there are some challenges to be overcome. This first one is that this chain must be competitive. There are some criteria to evaluate the competitiveness of chains. Also, it is known that Brazil has a big potential to export this kind of fuel. However, some countries are developing norms to evaluate whether this fuel is sustainable and whether it has positive impacts in society. The present work creates a model to evaluate bio-diesel chain suppliers using competitiveness and certification criteria identified in this chain. Smarter methodology was used in order to do so. This model was put

  13. Biomechanics of the transport barrier in the nuclear pore complex.

    Science.gov (United States)

    Stanley, George J; Fassati, Ariberto; Hoogenboom, Bart W

    2017-08-01

    The nuclear pore complex (NPC) is the selective gateway through which all molecules must pass when entering or exiting the nucleus. It is a cog in the gene expression pathway, an entrance to the nucleus exploited by viruses, and a highly-tuned nanoscale filter. The NPC is a large proteinaceous assembly with a central lumen occluded by natively disordered proteins, known as FG-nucleoporins (or FG-nups). These FG-nups, along with a family of soluble proteins known as nuclear transport receptors (NTRs), form the selective transport barrier. Although much is known about the transport cycle and the necessity of NTRs for chaperoning cargo molecules through the NPC, the mechanism by which NTRs and NTR•cargo complexes translocate the selective transport barrier is not well understood. How can disordered FG-nups and soluble NTRs form a transport barrier that is selective, ATP-free, and fast? In this work, we review various mechanical approaches - both experimental and theoretical/computational - employed to better understand the morphology of the FG-nups, and their role in nucleocytoplasmic transport. Recent experiments on FG-nups tethered to planar surfaces, coupled with quantitative modelling work suggests that FG-nup morphologies are the result of a finely balanced system with significant contributions from FG-nup cohesiveness and entropic repulsion, and from NTR•FG-nup binding avidity; whilst AFM experiments on intact NPCs suggest that the FG-nups are sufficiently cohesive to form condensates in the centre of the NPC lumen, which may transiently dissolve to facilitate the transport of larger cargoes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Scanning ion-selective electrode technique and X-ray microanalysis provide direct evidence of contrasting Na+ transport ability from root to shoot in salt-sensitive cucumber and salt-tolerant pumpkin under NaCl stress.

    Science.gov (United States)

    Lei, Bo; Huang, Yuan; Sun, Jingyu; Xie, Junjun; Niu, Mengliang; Liu, Zhixiong; Fan, Molin; Bie, Zhilong

    2014-12-01

    Grafting onto salt-tolerant pumpkin rootstock can increase cucumber salt tolerance. Previous studies have suggested that this can be attributed to pumpkin roots with higher capacity to limit the transport of Na(+) to the shoot than cucumber roots. However, the mechanism remains unclear. This study investigated the transport of Na(+) in salt-tolerant pumpkin and salt-sensitive cucumber plants under high (200 mM) or moderate (90 mM) NaCl stress. Scanning ion-selective electrode technique showed that pumpkin roots exhibited a higher capacity to extrude Na(+), and a correspondingly increased H(+) influx under 200 or 90 mM NaCl stress. The 200 mM NaCl induced Na(+)/H(+) exchange in the root was inhibited by amiloride (a Na(+)/H(+) antiporter inhibitor) or vanadate [a plasma membrane (PM) H(+) -ATPase inhibitor], indicating that Na(+) exclusion in salt stressed pumpkin and cucumber roots was the result of an active Na(+)/H(+) antiporter across the PM, and the Na(+)/H(+) antiporter system in salt stressed pumpkin roots was sufficient to exclude Na(+) X-ray microanalysis showed higher Na(+) in the cortex, but lower Na(+) in the stele of pumpkin roots than that in cucumber roots under 90 mM NaCl stress, suggesting that the highly vacuolated root cortical cells of pumpkin roots could sequester more Na(+), limit the radial transport of Na(+) to the stele and thus restrict the transport of Na(+) to the shoot. These results provide direct evidence for pumpkin roots with higher capacity to limit the transport of Na(+) to the shoot than cucumber roots. © 2014 Scandinavian Plant Physiology Society.

  15. Nitrogen transporter and assimilation genes exhibit developmental stage-selective expression in maize (Zea mays L.) associated with distinct cis-acting promoter motifs.

    Science.gov (United States)

    Liseron-Monfils, Christophe; Bi, Yong-Mei; Downs, Gregory S; Wu, Wenqing; Signorelli, Tara; Lu, Guangwen; Chen, Xi; Bondo, Eddie; Zhu, Tong; Lukens, Lewis N; Colasanti, Joseph; Rothstein, Steven J; Raizada, Manish N

    2013-10-01

    Nitrogen is considered the most limiting nutrient for maize (Zea mays L.), but there is limited understanding of the regulation of nitrogen-related genes during maize development. An Affymetrix 82K maize array was used to analyze the expression of ≤ 46 unique nitrogen uptake and assimilation probes in 50 maize tissues from seedling emergence to 31 d after pollination. Four nitrogen-related expression clusters were identified in roots and shoots corresponding to, or overlapping, juvenile, adult, and reproductive phases of development. Quantitative real time PCR data was consistent with the existence of these distinct expression clusters. Promoters corresponding to each cluster were screened for over-represented cis-acting elements. The 8-bp distal motif of the Arabidopsis 43-bp nitrogen response element (NRE) was over-represented in nitrogen-related maize gene promoters. This conserved motif, referred to here as NRE43-d8, was previously shown to be critical for nitrate-activated transcription of nitrate reductase (NIA1) and nitrite reductase (NIR1) by the NIN-LIKE PROTEIN 6 (NLP6) in Arabidopsis. Here, NRE43-d8 was over-represented in the promoters of maize nitrate and ammonium transporter genes, specifically those that showed peak expression during early-stage vegetative development. This result predicts an expansion of the NRE-NLP6 regulon and suggests that it may have a developmental component in maize. We also report leaf expression of putative orthologs of nitrite transporters (NiTR1), a transporter not previously reported in maize. We conclude by discussing how each of the four transcriptional modules may be responsible for the different nitrogen uptake and assimilation requirements of leaves and roots at different stages of maize development.

  16. A preliminary assessment of selected atmospheric dispersion, food-chain transport, and dose-to-man computer codes for use by the DOE Office of Civilian Radioactive Waste Management

    International Nuclear Information System (INIS)

    Riggle, K.J.; Roddy, J.W.

    1989-02-01

    This work is part of the ongoing Systems Modeling Program at Oak Ridge National Laboratory, which is assisting the DOE Office of Civilian Radioactive Waste Management in selecting appropriate computer codes for the process of licensing a high-level radioactive waste repository or a monitored retrievable storage facility. A preliminary study of codes for predicting dose to man following airborne releases of radionuclides is described. These codes use models for estimating atmospheric dispersion of activity and deposition onto the ground surface, exposures via external irradiation, inhalation of airborne activity, and ingestion following transport through terrestrial food chains, and the dose per unit exposure for each exposure mode. A set of criteria is given for use in choosing codes for further examination. From a list of over 150 computer codes, five were selected for review

  17. Identification of a New Class of Selective Excitatory Amino Acid Transporter Subtype 1 (EAAT1) Inhibitors Followed by a Structure-Activity-Relationship Study

    DEFF Research Database (Denmark)

    Hansen, Stinne Wessel; Erichsen, Mette Norman; Fu, Bingru

    2016-01-01

    in analogues with substantially improved inhibitory potencies at EAAT1 compared to that displayed by the hit, it provided a detailed insight into structural requirements for EAAT1 activity of this scaffold. The discovery of this new class of EAAT1-selective inhibitors not only supplements the currently...

  18. Semantic Coherence Facilitates Distributional Learning.

    Science.gov (United States)

    Ouyang, Long; Boroditsky, Lera; Frank, Michael C

    2017-04-01

    Computational models have shown that purely statistical knowledge about words' linguistic contexts is sufficient to learn many properties of words, including syntactic and semantic category. For example, models can infer that "postman" and "mailman" are semantically similar because they have quantitatively similar patterns of association with other words (e.g., they both tend to occur with words like "deliver," "truck," "package"). In contrast to these computational results, artificial language learning experiments suggest that distributional statistics alone do not facilitate learning of linguistic categories. However, experiments in this paradigm expose participants to entirely novel words, whereas real language learners encounter input that contains some known words that are semantically organized. In three experiments, we show that (a) the presence of familiar semantic reference points facilitates distributional learning and (b) this effect crucially depends both on the presence of known words and the adherence of these known words to some semantic organization. Copyright © 2016 Cognitive Science Society, Inc.

  19. Characteristic sounds facilitate visual search.

    Science.gov (United States)

    Iordanescu, Lucica; Guzman-Martinez, Emmanuel; Grabowecky, Marcia; Suzuki, Satoru

    2008-06-01

    In a natural environment, objects that we look for often make characteristic sounds. A hiding cat may meow, or the keys in the cluttered drawer may jingle when moved. Using a visual search paradigm, we demonstrated that characteristic sounds facilitated visual localization of objects, even when the sounds carried no location information. For example, finding a cat was faster when participants heard a meow sound. In contrast, sounds had no effect when participants searched for names rather than pictures of objects. For example, hearing "meow" did not facilitate localization of the word cat. These results suggest that characteristic sounds cross-modally enhance visual (rather than conceptual) processing of the corresponding objects. Our behavioral demonstration of object-based cross-modal enhancement complements the extensive literature on space-based cross-modal interactions. When looking for your keys next time, you might want to play jingling sounds.

  20. Characterisation of [11C]PR04.MZ in Papio anubis baboon: A selective high-affinity radioligand for quantitative imaging of the dopamine transporter

    Energy Technology Data Exchange (ETDEWEB)

    Riss P. J.; Fowler J.; Riss, P.J.; Hooker, J.M.; Shea, C.; Xu, Y.; Carter, P.; Warner, D.; Ferrari V.; Kim, S.W.; Aigbirhio, F.I.; Fowler, J.S.; Roesch, F.

    2011-10-25

    N-(4-fluorobut-2-yn-1-yl)-2{beta}-carbomethoxy-3{beta}-(4{prime}-tolyl)nortropane (PR04.MZ, 1) is a PET radioligand for the non-invasive exploration of the function of the cerebral dopamine transporter (DAT). A reliable automated process for routine production of the carbon-11 labelled analogue [{sup 11}C]PR04.MZ ([{sup 11}C]-1) has been developed using GMP compliant equipment. An adult female Papioanubis baboon was studied using a test-retest protocol with [{sup 11}C]-1 in order to assess test-retest reliability, metabolism and CNS distribution profile of the tracer in non-human primates. Blood sampling was performed throughout the studies for determination of the free fraction in plasma (fP), plasma input functions and metabolic degradation of the radiotracer [{sup 11}C]-1. Time-activity curves were derived for the putamen, the caudate nucleus, the ventral striatum, the midbrain and the cerebellum. Distribution volumes (VT) and non-displaceable binding potentials (BPND) for various brain regions and the blood were obtained from kinetic modelling. [{sup 11}C]-1 shows promising results as aselective marker of the presynaptic dopamine transporter. With the reliable visualisation of the extra-striatal dopaminergic neurons and no indication on labelled metabolites, the tracer provides excellent potential for translation into man.

  1. Multi-dimensional boron transport modeling in subchannel approach: Part I. Model selection, implementation and verification of COBRA-TF boron tracking model

    Energy Technology Data Exchange (ETDEWEB)

    Ozdemir, Ozkan Emre, E-mail: ozdemir@psu.edu [Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA 16802 (United States); Avramova, Maria N., E-mail: mna109@psu.edu [Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA 16802 (United States); Sato, Kenya, E-mail: kenya_sato@mhi.co.jp [Mitsubishi Heavy Industries (MHI), Kobe (Japan)

    2014-10-15

    Highlights: ► Implementation of multidimensional boron transport model in a subchannel approach. ► Studies on cross flow mechanism, heat transfer and lateral pressure drop effects. ► Verification of the implemented model via code-to-code comparison with CFD code. - Abstract: The risk of reflux condensation especially during a Small Break Loss Of Coolant Accident (SB-LOCA) and the complications of tracking the boron concentration experimentally inside the primary coolant system have stimulated and subsequently have been a focus of many computational studies on boron tracking simulations in nuclear reactors. This paper presents the development and implementation of a multidimensional boron transport model with Modified Godunov Scheme within a thermal-hydraulic code based on a subchannel approach. The cross flow mechanism in multiple-subchannel rod bundle geometry as well as the heat transfer and lateral pressure drop effects are considered in the performed studies on simulations of deboration and boration cases. The Pennsylvania State University (PSU) version of the COBRA-TF (CTF) code was chosen for the implementation of three different boron tracking models: First Order Accurate Upwind Difference Scheme, Second Order Accurate Godunov Scheme, and Modified Godunov Scheme. Based on the performed nodalization sensitivity studies, the Modified Godunov Scheme approach with a physical diffusion term was determined to provide the best solution in terms of precision and accuracy. As a part of the verification and validation activities, a code-to-code comparison was carried out with the STAR-CD computational fluid dynamics (CFD) code and presented here. The objective of this study was two-fold: (1) to verify the accuracy of the newly developed CTF boron tracking model against CFD calculations; and (2) to investigate its numerical advantages as compared to other thermal-hydraulics codes.

  2. Characterization of stormwater at selected South Carolina Department of Transportation maintenance yard and section shed facilities in Ballentine, Conway, and North Charleston, South Carolina, 2010-2012

    Science.gov (United States)

    Journey, Celeste A.; Conlon, Kevin J.

    2013-01-01

    The South Carolina Department of Transportation operates section shed and maintenance yard facilities throughout the State. The U.S. Geological Survey conducted a cooperative investigation with the South Carolina Department of Transportation to characterize water-quality constituents that are transported in stormwater from representative maintenance yard and section shed facilities in South Carolina. At a section shed in Ballentine, S.C., stormwater discharges to a retention pond outfall (Ballentine). At the Conway maintenance yard, stormwater in the southernmost section discharges to a pipe outfall (Conway1), and stormwater in the remaining area discharges to a grass-lined ditch (Conway2). At the North Charleston maintenance yard, stormwater discharges from the yard to Turkey Creek through a combination of pipes, ditches, and overland flow; therefore, samples were collected from the main channel of Turkey Creek at the upstream (North Charleston1) and downstream (North Charleston2) limits of the North Charleston maintenance yard facility. The storms sampled during this study had a wide range of rainfall amounts, durations, and intensities at each of the facilities and, therefore, were considered to be reasonably representative of the potential for contaminant transport. At all facilities, stormwater discharge was significantly correlated to rainfall amount and intensity. Event-mean unit-area stormwater discharge increased with increasing impervious surface at the Conway and North Charleston maintenance yards. The Ballentine facility with 79 percent impervious surface had a mean unit-area discharge similar to that of the North Charleston maintenance yard (62 percent impervious surface). That similarity may be attributed, in part, to the effects of the retention pond on the stormwater runoff at the Ballentine facility and to the greater rainfall intensities and amounts at the North Charleston facility. Stormwater samples from the facilities were analyzed for multiple

  3. Semantic Ambiguity: Do Multiple Meanings Inhibit or Facilitate Word Recognition?

    Science.gov (United States)

    Haro, Juan; Ferré, Pilar

    2018-06-01

    It is not clear whether multiple unrelated meanings inhibit or facilitate word recognition. Some studies have found a disadvantage for words having multiple meanings with respect to unambiguous words in lexical decision tasks (LDT), whereas several others have shown a facilitation for such words. In the present study, we argue that these inconsistent findings may be due to the approach employed to select ambiguous words across studies. To address this issue, we conducted three LDT experiments in which we varied the measure used to classify ambiguous and unambiguous words. The results suggest that multiple unrelated meanings facilitate word recognition. In addition, we observed that the approach employed to select ambiguous words may affect the pattern of experimental results. This evidence has relevant implications for theoretical accounts of ambiguous words processing and representation.

  4. Quantification of Transporter and Receptor Proteins in Dog Brain Capillaries and Choroid Plexus: Relevance for the Distribution in Brain and CSF of Selected BCRP and P-gp Substrates.

    Science.gov (United States)

    Braun, Clemens; Sakamoto, Atsushi; Fuchs, Holger; Ishiguro, Naoki; Suzuki, Shinobu; Cui, Yunhai; Klinder, Klaus; Watanabe, Michitoshi; Terasaki, Tetsuya; Sauer, Achim

    2017-10-02

    Transporters at the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCSFB) play a pivotal role as gatekeepers for efflux or uptake of endogenous and exogenous molecules. The protein expression of a number of them has already been determined in the brains of rodents, nonhuman primates, and humans using quantitative targeted absolute proteomics (QTAP). The dog is an important animal model for drug discovery and development, especially for safety evaluations. The purpose of the present study was to clarify the relevance of the transporter protein expression for drug distribution in the dog brain and CSF. We used QTAP to examine the protein expression of 17 selected transporters and receptors at the dog BBB and BCSFB. For the first time, we directly linked the expression of two efflux transporters, P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), to regional brain and CSF distribution using specific substrates. Two cocktails, each containing one P-gp substrate (quinidine or apafant) and one BCRP substrate (dantrolene or daidzein) were infused intravenously prior to collection of the brain. Transporter expression varied only slightly between the capillaries of different brain regions and did not result in region-specific distribution of the investigated substrates. There were, however, distinct differences between brain capillaries and choroid plexus. Largest differences were observed for BCRP and P-gp: both were highly expressed in brain capillaries, but no BCRP and only low amounts of P-gp were detected in the choroid plexus. K p,uu,brain and K p,uu,CSF of both P-gp substrates were indicative of drug efflux. Also, K p,uu,brain for the BCRP substrates was low. In contrast, K p,uu,CSF for both BCRP substrates was close to unity, resulting in K p,uu,CSF /K p,uu,brain ratios of 7 and 8, respectively. We conclude that the drug transporter expression profiles differ between the BBB and BCSFB in dogs, that there are species differences

  5. Role enactment of facilitation in primary care

    DEFF Research Database (Denmark)

    Due, Tina Drud; Thorsen, Thorkil; Waldorff, Frans Boch

    2017-01-01

    facilitation visits in 13 practice settings and had interviews and focus groups with facilitators. We applied an explorative approach in data collection and analysis, and conducted an inductive thematic analysis. RESULTS: The facilitators mainly enacted four facilitator roles: teacher, super user, peer...

  6. Role enactment of facilitation in primary care

    DEFF Research Database (Denmark)

    Due, Tina Drud; Thorsen, Thorkil; Waldorff, Frans Boch

    2017-01-01

    facilitation visits in 13 practice settings and had interviews and focus groups with facilitators. We applied an explorative approach in data collection and analysis, and conducted an inductive thematic analysis. Results: The facilitators mainly enacted four facilitator roles: teacher, super user, peer...

  7. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    J. Prouty

    2006-01-01

    from a breached waste package. Advective transport occurs when radionuclides that are dissolved or sorbed onto colloids (or both) are carried from the waste package by the portion of the seepage flux that passes through waste package breaches. Diffusive transport occurs as a result of a gradient in radionuclide concentration and may take place while advective transport is also occurring, as well as when no advective transport is occurring. Diffusive transport is addressed in detail because it is the sole means of transport when there is no flow through a waste package, which may dominate during the regulatory compliance period in the nominal and seismic scenarios. The advective transport rate, when it occurs, is generally greater than the diffusive transport rate. Colloid-facilitated advective and diffusive transport is also modeled and is presented in detail in Appendix B of this report

  8. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    J. Prouty

    2006-07-14

    from a breached waste package. Advective transport occurs when radionuclides that are dissolved or sorbed onto colloids (or both) are carried from the waste package by the portion of the seepage flux that passes through waste package breaches. Diffusive transport occurs as a result of a gradient in radionuclide concentration and may take place while advective transport is also occurring, as well as when no advective transport is occurring. Diffusive transport is addressed in detail because it is the sole means of transport when there is no flow through a waste package, which may dominate during the regulatory compliance period in the nominal and seismic scenarios. The advective transport rate, when it occurs, is generally greater than the diffusive transport rate. Colloid-facilitated advective and diffusive transport is also modeled and is presented in detail in Appendix B of this report.

  9. Computational simulation of lithium ion transport through polymer nanocomposite membranes

    International Nuclear Information System (INIS)

    Moon, P.; Sandi, G.; Kizilel, R.; Stevens, D.

    2003-01-01

    We think of membranes as simple devices to facilitate filtration. In fact, membranes play a role in chemical, biological, and engineering processes such as catalysis, separation, and sensing by control of molecular transport and recognition. Critical factors that influence membrane discrimination properties include composition, pore size (as well as homogeneity), chemical functionalization, and electrical transport properties. There is increasing interest in using nanomaterials for the production of novel membranes due to the unique selectivity that can be achieved. Clay-polymer nanocomposites show particular promise due to their ease of manufacture (large sheets), their rigidity (self supporting), and their excellent mechanical properties. However, the process of lithium ion transport through the clay-polymer nanocomposite and mechanisms of pore size selection are poorly understood at the ionic and molecular level. In addition, manufacturing of clay-polymer nanocomposite membranes with desirable properties has proved challenging. We have built a general membrane-modeling tool (simulation system) to assist in developing improved membranes for selection, electromigration, and other electrochemical applications. Of particular interest are the recently formulated clay-polymer membranes. The transport mechanisms of the lithium ions membranes are not well understood and, therefore, they make an interesting test case for the model. In order to validate the model, we synthesized polymer nanocomposites membranes.

  10. FACILITATING RADICAL FRONT-END INNOVATION THROUGH TARGETED HR PRACTICES

    DEFF Research Database (Denmark)

    Aagaard, Annabeth

    2017-01-01

    This study examines how radical front end innovation can be actively facilitated through selected and targeted HR practices and bundles of HR practices. The empirical field is an explorative case study of front end innovation and HR practices in the pharmaceutical industry, with an in-depth case ...

  11. DigiMemo: Facilitating the Note Taking Process

    Science.gov (United States)

    Kurt, Serhat

    2009-01-01

    Everyone takes notes daily for various reasons. Note taking is very popular in school settings and generally recognized as an effective learning strategy. Further, note taking is a complex process because it requires understanding, selection of information and writing. Some new technological tools may facilitate the note taking process. Among such…

  12. IT Project Selection

    DEFF Research Database (Denmark)

    Pedersen, Keld

    2016-01-01

    for initiation. Most of the research on project selection is normative, suggesting new methods, but available empirical studies indicate that many methods are seldom used in practice. This paper addresses the issue by providing increased understanding of IT project selection practice, thereby facilitating...... the development of methods that better fit current practice. The study is based on naturalistic decision-making theory and interviews with experienced project portfolio managers who, when selecting projects, primarily rely on political skills, experience and personal networks rather than on formal IT project......-selection methods, and these findings point to new areas for developing new methodological support for IT project selection....

  13. Induction of selective blood-tumor barrier permeability and macromolecular transport by a biostable kinin B1 receptor agonist in a glioma rat model.

    Science.gov (United States)

    Côté, Jérôme; Bovenzi, Veronica; Savard, Martin; Dubuc, Céléna; Fortier, Audrey; Neugebauer, Witold; Tremblay, Luc; Müller-Esterl, Werner; Tsanaclis, Ana-Maria; Lepage, Martin; Fortin, David; Gobeil, Fernand

    2012-01-01

    Treatment of malignant glioma with chemotherapy is limited mostly because of delivery impediment related to the blood-brain tumor barrier (BTB). B1 receptors (B1R), inducible prototypical G-protein coupled receptors (GPCR) can regulate permeability of vessels including possibly that of brain tumors. Here, we determine the extent of BTB permeability induced by the natural and synthetic peptide B1R agonists, LysdesArg(9)BK (LDBK) and SarLys[dPhe(8)]desArg(9)BK (NG29), in syngeneic F98 glioma-implanted Fischer rats. Ten days after tumor inoculation, we detected the presence of B1R on tumor cells and associated vasculature. NG29 infusion increased brain distribution volume and uptake profiles of paramagnetic probes (Magnevist and Gadomer) at tumoral sites (T(1)-weighted imaging). These effects were blocked by B1R antagonist and non-selective cyclooxygenase inhibitors, but not by B2R antagonist and non-selective nitric oxide synthase inhibitors. Consistent with MRI data, systemic co-administration of NG29 improved brain tumor delivery of Carboplatin chemotherapy (ICP-Mass spectrometry). We also detected elevated B1R expression in clinical samples of high-grade glioma. Our results documented a novel GPCR-signaling mechanism for promoting transient BTB disruption, involving activation of B1R and ensuing production of COX metabolites. They also underlined the potential value of synthetic biostable B1R agonists as selective BTB modulators for local delivery of different sized-therapeutics at (peri)tumoral sites.

  14. Induction of selective blood-tumor barrier permeability and macromolecular transport by a biostable kinin B1 receptor agonist in a glioma rat model.

    Directory of Open Access Journals (Sweden)

    Jérôme Côté

    Full Text Available Treatment of malignant glioma with chemotherapy is limited mostly because of delivery impediment related to the blood-brain tumor barrier (BTB. B1 receptors (B1R, inducible prototypical G-protein coupled receptors (GPCR can regulate permeability of vessels including possibly that of brain tumors. Here, we determine the extent of BTB permeability induced by the natural and synthetic peptide B1R agonists, LysdesArg(9BK (LDBK and SarLys[dPhe(8]desArg(9BK (NG29, in syngeneic F98 glioma-implanted Fischer rats. Ten days after tumor inoculation, we detected the presence of B1R on tumor cells and associated vasculature. NG29 infusion increased brain distribution volume and uptake profiles of paramagnetic probes (Magnevist and Gadomer at tumoral sites (T(1-weighted imaging. These effects were blocked by B1R antagonist and non-selective cyclooxygenase inhibitors, but not by B2R antagonist and non-selective nitric oxide synthase inhibitors. Consistent with MRI data, systemic co-administration of NG29 improved brain tumor delivery of Carboplatin chemotherapy (ICP-Mass spectrometry. We also detected elevated B1R expression in clinical samples of high-grade glioma. Our results documented a novel GPCR-signaling mechanism for promoting transient BTB disruption, involving activation of B1R and ensuing production of COX metabolites. They also underlined the potential value of synthetic biostable B1R agonists as selective BTB modulators for local delivery of different sized-therapeutics at (peritumoral sites.

  15. GIS-facilitated spatial narratives

    DEFF Research Database (Denmark)

    Møller-Jensen, Lasse; Jeppesen, Henrik; Kofie, Richard Y.

    2008-01-01

    on the thematically and narrative linking of a set of locations within an area. A spatial narrative that describes the - largely unsuccessful - history of Danish plantations on the Gold Coast (1788-1850) is implemented through the Google Earth client. This client is seen both as a type of media in itself for ‘home......-based' exploration of sites related to the narrative and as a tool that facilitates the design of spatial narratives before implementation within portable GIS devices. The Google Earth-based visualization of the spatial narrative is created by a Python script that outputs a web-accessible KML format file. The KML...

  16. Radiation Transport

    Energy Technology Data Exchange (ETDEWEB)

    Urbatsch, Todd James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-06-15

    We present an overview of radiation transport, covering terminology, blackbody raditation, opacities, Boltzmann transport theory, approximations to the transport equation. Next we introduce several transport methods. We present a section on Caseology, observing transport boundary layers. We briefly broach topics of software development, including verification and validation, and we close with a section on high energy-density experiments that highlight and support radiation transport.

  17. Analysis of postfire hydrology, water quality, and sediment transport for selected streams in areas of the 2002 Hayman and Hinman fires, Colorado

    Science.gov (United States)

    Stevens, Michael R.

    2013-01-01

    The U.S. Geological Survey (USGS) began a 5-year study in 2003 that focused on postfire stream-water quality and postfire sediment load in streams within the Hayman and Hinman fire study areas. This report compares water quality of selected streams receiving runoff from unburned areas and burned areas using concentrations and loads, and trend analysis, from seasonal data (approximately April–November) collected 2003–2007 at the Hayman fire study area, and data collected from 1999–2000 (prefire) and 2003 (postfire) at the Hinman fire study area. The water-quality data collected during this study include onsite measurements of streamflow, specific conductance, and turbidity, laboratory-determined pH, and concentrations of major ions, nutrients, organic carbon, trace elements, and suspended sediment. Postfire floods and effects on water quality of streams, lakes and reservoirs, drinking-water treatment, and the comparison of measured concentrations to applicable water quality standards also are discussed. Exceedances of Colorado water-quality standards in streams of both the Hayman and Hinman fire study areas only occurred for concentrations of five trace elements (not all trace-element exceedances occurred in every stream). Selected samples analyzed for total recoverable arsenic (fixed), dissolved copper (acute and chronic), total recoverable iron (chronic), dissolved manganese (acute, chronic, and fixed) and total recoverable mercury (chronic) exceeded Colorado aquatic-life standards.

  18. Study on welding thermal cycle and residual stress of UNS S32304 duplex steel selected as external shield for a transport packaging of Mo-99

    International Nuclear Information System (INIS)

    Betini, Evandro G.; Gomes, Maurilio P.; Milagre, Mariana X.; Machado, Caruline S.C.; Reis, Luis A.M.; Mucsi, Cristiano S.; Rossi, Jesualdo L.; Orlando, Marcos T.D.; Luz, Temístocles S.

    2017-01-01

    Thin plates of duplex stainless steel UNS S32304 were welded using the pulsed gas tungsten arc GTAW process (butt joint) without filler addition. The used shielding gas was pure argon and 98% argon plus 2% of nitrogen. The thermal cycles were acquired during welding, in regions near the melting pool. This alloy is candidate for the external clad of a cask for the transport of high activity radiopharmaceuticals substances. For the residual stress measurements in austenite phase an X-ray diffractometer was used in a Bragg-Brentano geometry with CuKα radiation (γ= 0.154 and for ferrite phase was used a pseudo-parallel geometry with CrKα radiation (γ= 0.2291 nm). The results of residual stress using sin 2 Ψ methodology shown that the influence of the high welding temperature leads to compressive stresses in for both phase of the duplex steels mainly in heat-affected zone. It was observed a high temperature peak and an increase of the mean residual stress after addition of nitrogen to the argon shielding gas. (author)

  19. Effects of citalopram and escitalopram on fMRI response to affective stimuli in healthy volunteers selected by serotonin transporter genotype.

    Science.gov (United States)

    Henry, Michael E; Lauriat, Tara L; Lowen, Steven B; Churchill, Jeffrey H; Hodgkinson, Colin A; Goldman, David; Renshaw, Perry F

    2013-09-30

    This study was designed to assess whether functional magnetic resonance imaging (fMRI) following antidepressant administration (pharmaco-fMRI) is sufficiently sensitive to detect differences in patterns of activation between enantiomers of the same compound. Healthy adult males (n=11) participated in a randomized, double-blind, cross-over trial with three medication periods during which they received citalopram (racemic mixture), escitalopram (S-citalopram alone), or placebo for 2 weeks. All participants had high expression serotonin transporter genotypes. An fMRI scan that included passive viewing of overt and covert affective faces and affective words was performed after each medication period. Activation in response to overt faces was greater following escitalopram than following citalopram in the right insula, thalamus, and putamen when the faces were compared with a fixation stimulus. For the rapid covert presentation, a greater response was observed in the left middle temporal gyrus in the happy versus fearful contrast following escitalopram than following citalopram. Thus, the combination of genomics and fMRI was successful in discriminating between two very similar drugs. However, the pattern of activation observed suggests that further studies are indicated to understand how to optimally combine the two techniques. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Design, analysis, and control of a large transport aircraft utilizing selective engine thrust as a backup system for the primary flight control. Ph.D. Thesis

    Science.gov (United States)

    Gerren, Donna S.

    1995-01-01

    A study has been conducted to determine the capability to control a very large transport airplane with engine thrust. This study consisted of the design of an 800-passenger airplane with a range of 5000 nautical miles design and evaluation of a flight control system, and design and piloted simulation evaluation of a thrust-only backup flight control system. Location of the four wing-mounted engines was varied to optimize the propulsive control capability, and the time constant of the engine response was studied. The goal was to provide level 1 flying qualities. The engine location and engine time constant did not have a large effect on the control capability. The airplane design did meet level 1 flying qualities based on frequencies, damping ratios, and time constants in the longitudinal and lateral-directional modes. Project pilots consistently rated the flying qualities as either level 1 or level 2 based on Cooper-Harper ratings. However, because of the limited control forces and moments, the airplane design fell short of meeting the time required to achieve a 30 deg bank and the time required to respond a control input.

  1. Study on welding thermal cycle and residual stress of UNS S32304 duplex steel selected as external shield for a transport packaging of Mo-99

    Energy Technology Data Exchange (ETDEWEB)

    Betini, Evandro G.; Gomes, Maurilio P.; Milagre, Mariana X.; Machado, Caruline S.C.; Reis, Luis A.M.; Mucsi, Cristiano S.; Rossi, Jesualdo L., E-mail: egbetini@ipen.br [Instituto de Pesquisas Energética s e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil); Orlando, Marcos T.D.; Luz, Temístocles S., E-mail: mtdorlando@gmail.com [Universidade Federal do Espirito Santo (DFIS/UFES), Vitória, ES (Brazil). Departamento de Física

    2017-07-01

    Thin plates of duplex stainless steel UNS S32304 were welded using the pulsed gas tungsten arc GTAW process (butt joint) without filler addition. The used shielding gas was pure argon and 98% argon plus 2% of nitrogen. The thermal cycles were acquired during welding, in regions near the melting pool. This alloy is candidate for the external clad of a cask for the transport of high activity radiopharmaceuticals substances. For the residual stress measurements in austenite phase an X-ray diffractometer was used in a Bragg-Brentano geometry with CuKα radiation (γ= 0.154 and for ferrite phase was used a pseudo-parallel geometry with CrKα radiation (γ= 0.2291 nm). The results of residual stress using sin{sup 2} Ψ methodology shown that the influence of the high welding temperature leads to compressive stresses in for both phase of the duplex steels mainly in heat-affected zone. It was observed a high temperature peak and an increase of the mean residual stress after addition of nitrogen to the argon shielding gas. (author)

  2. The Relationships between Human Fatigue and Public Health: A Brief Commentary on Selected Papers from the 9th International Conference on Managing Fatigue in Transportation, Resources and Health.

    Science.gov (United States)

    Sargent, Charli; Roberts, Paul; Dawson, Drew; Ferguson, Sally; Meuleners, Lynn; Brook, Libby; Roach, Gregory D

    2016-08-24

    The 9th International Conference on Managing Fatigue in Transportation, Resources and Health was held in Fremantle, Western Australia in March 2015. The purpose of the conferences in this series is to provide a forum for industry representatives, regulators, and scientists to discuss recent advances in the field of fatigue research. We have produced a Special Issue of the International Journal of Environmental Research and Public Health based on papers from the conference that were focused on various aspects of public health. First, the Special Issue highlights the fact that working long shifts and/or night shifts can affect not only cognitive functioning, but also physical health. In particular, three papers examined the potential relationships between shiftwork and different aspects of health, including the cardiovascular system, sleep disordered breathing, and eating behaviour. Second, the Special Issue highlights the move away from controlling fatigue through prescriptive hours of service rules and toward the application of risk management principles. In particular, three papers indicated that best-practice fatigue risk management systems should contain multiple redundant layers of defense against fatigue-related errors and accidents.

  3. The Relationships between Human Fatigue and Public Health: A Brief Commentary on Selected Papers from the 9th International Conference on Managing Fatigue in Transportation, Resources and Health

    Directory of Open Access Journals (Sweden)

    Charli Sargent

    2016-08-01

    Full Text Available The 9th International Conference on Managing Fatigue in Transportation, Resources and Health was held in Fremantle, Western Australia in March 2015. The purpose of the conferences in this series is to provide a forum for industry representatives, regulators, and scientists to discuss recent advances in the field of fatigue research. We have produced a Special Issue of the International Journal of Environmental Research and Public Health based on papers from the conference that were focused on various aspects of public health. First, the Special Issue highlights the fact that working long shifts and/or night shifts can affect not only cognitive functioning, but also physical health. In particular, three papers examined the potential relationships between shiftwork and different aspects of health, including the cardiovascular system, sleep disordered breathing, and eating behaviour. Second, the Special Issue highlights the move away from controlling fatigue through prescriptive hours of service rules and toward the application of risk management principles. In particular, three papers indicated that best-practice fatigue risk management systems should contain multiple redundant layers of defense against fatigue-related errors and accidents.

  4. Voice congruency facilitates word recognition.

    Directory of Open Access Journals (Sweden)

    Sandra Campeanu

    Full Text Available Behavioral studies of spoken word memory have shown that context congruency facilitates both word and source recognition, though the level at which context exerts its influence remains equivocal. We measured event-related potentials (ERPs while participants performed both types of recognition task with words spoken in four voices. Two voice parameters (i.e., gender and accent varied between speakers, with the possibility that none, one or two of these parameters was congruent between study and test. Results indicated that reinstating the study voice at test facilitated both word and source recognition, compared to similar or no context congruency at test. Behavioral effects were paralleled by two ERP modulations. First, in the word recognition test, the left parietal old/new effect showed a positive deflection reflective of context congruency between study and test words. Namely, the same speaker condition provided the most positive deflection of all correctly identified old words. In the source recognition test, a right frontal positivity was found for the same speaker condition compared to the different speaker conditions, regardless of response success. Taken together, the results of this study suggest that the benefit of context congruency is reflected behaviorally and in ERP modulations traditionally associated with recognition memory.

  5. Voice congruency facilitates word recognition.

    Science.gov (United States)

    Campeanu, Sandra; Craik, Fergus I M; Alain, Claude

    2013-01-01

    Behavioral studies of spoken word memory have shown that context congruency facilitates both word and source recognition, though the level at which context exerts its influence remains equivocal. We measured event-related potentials (ERPs) while participants performed both types of recognition task with words spoken in four voices. Two voice parameters (i.e., gender and accent) varied between speakers, with the possibility that none, one or two of these parameters was congruent between study and test. Results indicated that reinstating the study voice at test facilitated both word and source recognition, compared to similar or no context congruency at test. Behavioral effects were paralleled by two ERP modulations. First, in the word recognition test, the left parietal old/new effect showed a positive deflection reflective of context congruency between study and test words. Namely, the same speaker condition provided the most positive deflection of all correctly identified old words. In the source recognition test, a right frontal positivity was found for the same speaker condition compared to the different speaker conditions, regardless of response success. Taken together, the results of this study suggest that the benefit of context congruency is reflected behaviorally and in ERP modulations traditionally associated with recognition memory.

  6. ANALYISIS OF TRANSPORTATION SYSTEMS AND TRANSPORTATION POLICIES IN TURKEY

    Directory of Open Access Journals (Sweden)

    Ali Payıdar AKGÜNGÖR

    2004-03-01

    Full Text Available Transportation systems have to be considered and analysed as a whole while transportation demand, becoming as a natural outcome of socioeconomic and socio-cultural structure, is being evaluated. It is desired that transportation system, which will be selected for both passenger and freight transport, should be rapid, economic, safe, causing least harm to environment and appropriate for the conditions of a country. However, it is difficult for a transportation system to have all these properties. Every transportation system has advantages and disadvantages over each other. Therefore, comprehensive plans for future periods have to be prepared and how the sources of the country should be reasonably distributed among transportation systems must be investigated. Also, transportation plans have to be prepared to get coordinated operations among transportation systems while great investments are instituted in the entire country. There is no doubt that it is possible with combined transportation instead of concentration on one transportation system. Transportation policies in Turkey should be questioned since the level of highway transportation usage reaches to 95 % and level of sea transportation usage drops to less than 1 % in spite of being surrounded with sea in three sides of our land. In this paper, transportation systems and transportation policies in Turkey are evaluated in general and problems are analysed. Proposals are presented for the solutions of these problems.

  7. Pharmacological Identification of a Guanidine-Containing β-Alanine Analogue with Low Micromolar Potency and Selectivity for the Betaine/GABA Transporter 1 (BGT1)

    DEFF Research Database (Denmark)

    Al-Khawaja, Anas Mohammad Ali; Petersen, Jette Gellert; Damgaard, Maria

    2014-01-01

    of the amino group in β-alanine or GABA, a series of compounds was generated, and their pharmacological activity assessed at human GAT subtypes. Using a cell-based [(3)H]GABA uptake assay, several selective inhibitors at human BGT1 were identified. The guanidine-containing compound 9 (2-amino-1......,4,5,6-tetrahydropyrimidine-5-carboxylic acid hydrochloride) displayed more than 250 times greater potency than the parent compound β-alanine at BGT1 and is thus the most potent inhibitor reported to date for this subtype (IC50 value of 2.5 µM). In addition, compound 9 displayed about 400, 16 and 40 times lower inhibitory...

  8. Radioiodinated 4-iodo-L-meta-tyrosine, a system L selective artificial amino acid: molecular design and transport characterization in Chinese hamster ovary cells (CHO-K1 cells)

    Energy Technology Data Exchange (ETDEWEB)

    Shikano, Naoto, E-mail: sikano@ipu.ac.j [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Kotani, Takashi; Nakajima, Syuichi; Ogura, Masato; Nakazawa, Shinya [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Sagara, Jun-ichi [Center for Humanities and Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Kobayashi, Masato [Division of Health Science, Graduate School of Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, Ishikawa 9200-942 (Japan); Baba, Takeshi; Yamaguchi, Naoto [Center for Medical Science, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Kubota, Nobuo [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Kawai, Keiichi [Division of Health Science, Graduate School of Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, Ishikawa 9200-942 (Japan)

    2010-11-15

    Introduction: High expression of the system L amino acid transporter has been observed in clinically important tissues including tumors and the blood-brain barrier. We examined amino acid transport system L selectivity of {sup 14}C(U)-L-tyrosine ({sup 14}C-Tyr), {sup 125}I-4-iodo-L-meta-tyrosine (4-{sup 125}I-mTyr), {sup 125}I-6-iodo-L-meta-tyrosine (6-{sup 125}I-mTyr), {sup 125}I-3-iodo-{alpha}-methyl-L-tyrosine ({sup 125}I-IMT) and {sup 125}I-3-iodo-L-tyrosine (3-{sup 125}I-Tyr) using Chinese hamster ovary cells (CHO-K1). Methods: Cells in the exponential growth phase were incubated with 18.5 kBq of labeled amino acid in 2 mL of phosphate-buffered saline-based uptake solution and an uptake solution with/without Na{sup +} at 37{sup o}C or 4{sup o}C. We examined the effects of the following compounds (1.0 mM) on transport: 2-(methylamino)isobutyric acid (a specific inhibitor of system A, in Na{sup +}-containing uptake solution); 2-amino-bicyclo[2,2,1]heptane-2-carboxylic acid (a specific inhibitor of system L, in Na{sup +}-free uptake solution); sodium azide and 2,4-dinitrophenol (NaN{sub 3} and DNP, inhibitors of the generation of adenosine triphosphate); p-aminohippurate and tetraethylammonium (PAH and TEA, inhibitors of organic anion and cation transporters); and L- and D-isomers of natural amino acids. Results: {sup 14}C-Tyr exhibited affinity for systems L, A and ASC. 4-{sup 125}I-mTyr and 3-{sup 125}I-Tyr exhibited high specificity for system L, whereas 6-{sup 125}I-mTyr and {sup 125}I-IMT exhibited affinity for both systems L and ASC. Uptake of 4-{sup 125}I-mTyr was markedly reduced by incubation at 4 {sup o}C, and was not significantly inhibited by NaN{sub 3}, DNP, PAH or TEA. The inhibition profiles of the L- and D-isomers of natural amino acids indicated that system L mediates the transport of 4-{sup 125}I-mTyr. Conclusions: 4-{sup 125}I-mTyr exhibited the greatest system L specificity (93.46{+-}0.13%) of all of the tested amino acids.

  9. Facilitating Shared Understandings of Risk

    DEFF Research Database (Denmark)

    Mitchell, Robb

    This thesis contributes an identification of a key mechanism and its constituent qualities, for facilitating shared understandings of risk. Globalisation and the pace of technological change increases the uncertainties of decision making within many design and innovation practices. Accordingly......, the focus of participatory workshops has expanded towards addressing broader questions of strategy, business models and other organizational and inter-organisational issues. To develop effective partnerships across the boundaries separating companies, I argue that is necessary for those involved to gain...... or proxy for absent others, 4) an incomplete comic with which children could contribute sketched ideas to a design process 5) a table top tool kits for discussing business relationship issues and 5) a number of bespoke interactive sculpture-like artifacts for provoking insights concerning business dilemmas...

  10. Anterior ethmoid anatomy facilitates dacryocystorhinostomy.

    Science.gov (United States)

    Blaylock, W K; Moore, C A; Linberg, J V

    1990-12-01

    The ethmoid air cell labyrinth lies adjacent to the medial orbital wall, extending even beyond the sutures of the ethmoid bone. Its anatomic relationship to the lacrimal sac fossa is important in lacrimal surgery. We evaluated computed tomographic scans of 190 orbits with normal ethmoid anatomy to define the anatomic relationship of anterior ethmoid air cells to the lacrimal sac fossa. In 93% of the orbits, the cells extended anterior to the posterior lacrimal crest, with 40% entering the frontal process of the maxilla. This anatomic relationship may be used to facilitate the osteotomy during dacryocystorhinostomy. During a 10-year period (310 cases), one of us routinely entered the anterior ethmoid air cells to initiate the osteotomy during dacryocystorhinostomy. This technique has helped to avoid lacerations of the nasal mucosa.

  11. Facilitating Value Co-Creation

    DEFF Research Database (Denmark)

    Veith, Anne; Assaf, Albert; Josiassen, Alexander

    2013-01-01

    will also lead to a high rewards. According to postmodern consumerism theory, consumers are intrinsically motivated to participate (Arnould et al., 2006; Borghini & Caru, 2008; Etgar, 2008; Fisher & Smith, 2011), but may also be extrinsic motivated by, for instance, appraisal and 'autonomy' (Etgar, 2008......). Therefore, for instance, being part of the process is a key incentive for consumers. Postmodern consumers' search for unique experiences calls for individualization, personalization, etc. Although Prahalad & Ramaswamy (2004), Karpen et al. (2008), and Karpen et al. (2011) have presented S-D Logic...... as a middle range theory it is still difficult for organizations to operationalize their co-creation efforts. This paper argues that postmodern consumerism can be used to guide the operationalization of the co-creation process by identifying the key facilitators of co-creation for the postmodern consumer...

  12. Transport of water in proximal kidney tubules from whole tubules to single channels: length and section of the selectivity filter of aquaporin-1.

    Science.gov (United States)

    Whittembury, G; González, E; Hernández, C S; Gutiérrez, A M; Echevarría, M

    1997-06-27

    Proximal straight tubule (PST) were dissected from rabbit kidneys, held with crimping pipettes in a chamber bathed in a buffered mannitol isosmotic solution (MBS, 295 mOsm/kg). Tubule cell volume changes with time (dV/Adt) after steps in MBS osmolality (delta Cs) were monitored on line with an inverted microscope, a TV camera and an image processor. Reflection coefficients sigma and osmotic permeability coefficients, Pos, for several solutes were measured using two methods. Method 1: sigma was calculated from the delta Csiso of impermeant and permeant solutes at which (dV/Adt)t-->0 = 0 (i.e., by a null point method). It is denoted as sigma 1. sigma 1 = 1.00 for mannitol (M), raffinose (R), sucrose (S), glycerol (G), acetamide (A) and urea (U). With formamide (F), sigma 1, Formamide = 0.62 +/- 0.05. These findings confirm our previous value of dp = 4.5 A for the diameter of the selectivity filter of the basolateral PST cell membrane water channel AQP1. Method 2: PST were exposed for 20 s to MBS made hyperosmotic by addition of a delta Cs of 35 mOsm/kg of R, S, M, G, A and U. Cells shrunk within 500 ms of t = 0 to their osmometric volume and remained shrunk for the 20 s of the osmotic challenge. Pos was measured from the shrinking curves. P(os) = 3000 +/- 25 microns/s with R, S, M, G, A and U. Method 2 also allowed to calculate sigma, denoted as sigma 2. sigma 2 = 1.00 for R, S, M, G, A and U. By contrast, the shrinking curve produced by a delta Cs of 35 mOsm/kg F was 1/5th to 1/6th slower and smaller (i.e., subosmometric) than that produced by a delta Cs of 35 mOsm/kg R, S, M, G, A and U. Furthermore, with F cells did not remain shrunk but recovered their original volume within 3 s. P(os) (measured with F) is denoted as P(os)*, P(os)* = 480 +/- 30 microns/s. sigma 2, Formamide = 0.16 +/- 0.01. Use of sigma 1, sigma 2 and P(os)* values in Hill's equations for the bimodal theory of osmosis leads to n = 2-9. Where n is the number of water molecules single filling

  13. Selective GABA transporter inhibitors tiagabine and EF1502 exhibit mechanistic differences in their ability to modulate the ataxia and anticonvulsant action of the extrasynaptic GABA(A) receptor agonist gaboxadol

    DEFF Research Database (Denmark)

    Madsen, Karsten Kirkegaard; Ebert, Bjarke; Clausen, Rasmus Prætorius

    2011-01-01

    seizures. Even though less is known about the therapeutic potential of other GABA transport inhibitors, previous investigations have demonstrated that N-[4,4-bis(3-methyl-2-thienyl)-3-butenyl]-3-hydroxy-4-(methylamino)-4,5,6,7-tetrahydrobenzo[d]isoxazol-3-ol (EF1502), which, like tiagabine, is inactive...... of gaboxadol (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol), which, at the doses used in this study (i.e., 1-5 mg/kg) selectively activates extrasynaptic a4-containing GABA(A) receptors, was determined alone and in combination with either tiagabine or EF1502 using Frings audiogenic seizure-susceptible and CF...

  14. Source and transport controls on the movement of nitrate to public supply wells in selected principal aquifers of the United States

    Science.gov (United States)

    McMahon, P. B.; BöHlke, J. K.; Kauffman, L. J.; Kipp, K. L.; Landon, M. K.; Crandall, C. A.; Burow, K. R.; Brown, C. J.

    2008-04-01

    In 2003-2005, systematic studies in four contrasting hydrogeologic settings were undertaken to improve understanding of source and transport controls on nitrate movement to public supply wells (PSW) in principal aquifers of the United States. Chemical, isotopic, and age tracer data show that agricultural fertilizers and urban septic leachate were the primary sources of large nitrate concentrations in PSW capture zones at Modesto, California (Central Valley aquifer system) and York, Nebraska (High Plains aquifer). Urban septic leachate and fertilizer (possibly nonfarm) were the primary sources of large nitrate concentrations in PSW capture zones at Woodbury, Connecticut (glacial aquifer system), and Tampa, Florida (Floridan aquifer system), respectively. Nitrate fluxes to the water table were larger in agricultural settings than urban settings, indicating that it would be beneficial to reduce PSW capture zone areas in agricultural regions. Mixing calculations indicate that about 50 to 85% of the nitrate in water from the PSW could be from those modern anthropogenic sources, with the remainder coming from sources in old (>50 years) recharge or sources in young recharge in undisturbed settings such as forests. Excess N2 concentrations and age tracers showed that denitrification at Modesto occurred gradually (first-order rate constant of 0.02/a) in a thick reaction zone following a ˜30-year lag time after recharge. Denitrification generally was not an important nitrate sink at Woodbury. At York and Tampa, denitrification occurred rapidly (0.5 to 6/a) in thin reaction zones in fine-grained sediments that separated the anoxic PSW producing zones from overlying oxic, high-nitrate ground water. Particle tracking showed that a major pathway by which anthropogenic nitrate reached the York and Tampa PSW was by movement through long well screens crossing multiple hydrogeologic units (York) and by movement through karst features (Tampa), processes which reduced ground water

  15. Analysis of the transport flows service time of the vehicles and the assessment of the ideterminancy of external impact

    Directory of Open Access Journals (Sweden)

    A. Jarašūnienė

    2003-10-01

    Full Text Available To increase the attraction of Lithuania as a transit country striving to promote carriers' border crossing activities and facilitate customs clearance procedures as well as freight delivery to clients it is necessary to identify the main obstacles, to analyse them and to select adequate measures and means for their elimination. Therefore, on the basis of the analysis of the transport flows service time, as well as basing on the assessment of indeterminacy of external impacts, it would be possible to deduce the main causes of idle time of transport means at customs, to estimate the dependence of service time in proportion to transport flows. Basing on theoretical estimation in this article the estimation of service time of international transport and the management of transport flows are described.

  16. Ion selectivity of the cation transport system of isolated intact cattle rod outer segments: evidence for a direct communication between the rod plasma membrane and the rod disk membranes.

    Science.gov (United States)

    Schnetkamp, P P

    1980-05-08

    The ion selectivity of cation transport through the plasma membrane of isolated intact cattle rod outer segments (rods) is investigated by means of 45Ca-exchange experiments and light-scattering experiments. These techniques appear to provide complementary information: the 45Ca experiments (45Ca fluxes in rods) describe electroneutral antiport, whereas the light-scattering experiments (shrinkage and swelling of rods upon hypertonic shocks with various electrolytes) reveal electrogenic uniport. Electroneutral symport of ions (salt transport) does not take place without addition of external ionophores and application of salts of weak acids. 1. Intact rods recover from a hypertonic shock in the presence of FCCP when lithium, sodium and potassium acetate are applied, but not when ammonium chloride, calcium and magnesium acetate are used. This indicates that the plasma membrane of isolated intact cattle rods is relatively permeable to net transport of Na+, Li+ and K+, and relatively impermeable to net transport of Cl-, Mg2+ and Ca2+ under conditions that do not give rise to diffusion potentials. 2. Rapid (t1/2 exchange diffusion of internal 45Ca with external Na+, Ca2+, Sr2+ and Ba2+, respectively. 3. All tested cations lower the rate of 45Ca uptake. The latter can be described by a single rate constant indicating a homogeneous rod preparation and a homogeneous endogenous Ca2+ pool. However, only those cations which stimulate 45Ca efflux from preloaded rods lower the final equilibrium of 45Ca uptake. Except for the effects of K+, Rb+ and Cs+ the reduction of the rate of 45Ca uptake by external cations appears to arise from competition for a common site on the plasms membrane. The observed affinities for this site do not correlate with actual transport (as indicated by the ability to stimulate 45Ca efflux). 4. K+ increases the affinity of the exchange diffusion system to Ca2+ from 1 microM to 0.15 microM and changes the relative affinities with respect to Ca2+ for the

  17. Selective decontamination of cesium and strontium from evaporation concentrates of spent fuel reprocessing plants with crown ethers by transport through supported liquid membranes

    International Nuclear Information System (INIS)

    Casas i Garcia, J.

    1993-01-01

    Reprocessing operations lead to the production of radioactive medium activity liquid waste which is treated by evaporation and solutions of very high salinity are thus formed. The concentrates from reprocessing plant evaporators have to be stored in geological storage sites in view of their strong caesium, strontium and actinides activity. These elements, contained in acid and high sodium nitrate content liquid waste, are removed by means of selective extractants, using the supported liquid membrane technique (SLM), which allows them to be stored in surface sites, the actinides and long-life fission products being respectively recycled and concentrated into reduced volumes. The removal of the actinides is done by means of an Octyl N.N Diisobutyl Carbamoyl Methyl Phosphine Oxide (C.M.P.O.) based liquid membrane, whereas the removal of the caesium and strontium involves crown ethers. Supported liquid membranes (S.L.M.s) have the advantage of implementing very small quantities of extractant, but they generally have poor stability. The extractant, the diluent and the phase modifier impregnating the membrane play a vital role in SLM stability; the support also affects stability by its nature and geometry. For the extraction of strontium, the most lipophilic extractant, DtBu 18 C 6, enables higher strontium transfer kinetics to be attained. As regards caesium, the extremely lipophilic nDec B21 C7 is the most efficient. Caesium cannot be quantitatively removed, due to the competition of the very high content of sodium ions in the concentrate. Stable membranes are obtained with DC18 C6 or DtBu18 C6 diluted in alkylbenzenes with an added phase modifier such as decanol or especially isotridecanol

  18. Citation bias and selective focus on positive findings in the literature on the serotonin transporter gene (5-HTTLPR), life stress and depression.

    Science.gov (United States)

    de Vries, Y A; Roest, A M; Franzen, M; Munafò, M R; Bastiaansen, J A

    2016-10-01

    Caspi et al.'s 2003 report that 5-HTTLPR genotype moderates the influence of life stress on depression has been highly influential but remains contentious. We examined whether the evidence base for the 5-HTTLPR-stress interaction has been distorted by citation bias and a selective focus on positive findings. A total of 73 primary studies were coded for study outcomes and focus on positive findings in the abstract. Citation rates were compared between studies with positive and negative results, both within this network of primary studies and in Web of Science. In addition, the impact of focus on citation rates was examined. In all, 24 (33%) studies were coded as positive, but these received 48% of within-network and 68% of Web of Science citations. The 38 (52%) negative studies received 42 and 23% of citations, respectively, while the 11 (15%) unclear studies received 10 and 9%. Of the negative studies, the 16 studies without a positive focus (42%) received 47% of within-network citations and 32% of Web of Science citations, while the 13 (34%) studies with a positive focus received 39 and 51%, respectively, and the nine (24%) studies with a partially positive focus received 14 and 17%. Negative studies received fewer citations than positive studies. Furthermore, over half of the negative studies had a (partially) positive focus, and Web of Science citation rates were higher for these studies. Thus, discussion of the 5-HTTLPR-stress interaction is more positive than warranted. This study exemplifies how evidence-base-distorting mechanisms undermine the authenticity of research findings.

  19. Selective decontamination for cesium and strontium in evaporation concentrates from reprocessing plants with crown ethers by transport through supported liquid membranes

    International Nuclear Information System (INIS)

    Casas i Garcia, J.

    1991-01-01

    Reprocessing operations lead to the production of radioactive medium activity liquid waste which is treated by evaporation. The concentrates from reprocessing plant evaporators have to be stored in geological storage sites in view of their strong caesium, strontium and actinides activity. These elements, contained in acid and high sodium nitrate content liquid waste, are removed by means of selective extractants, using the supported liquid membrane technique (SLM), which allows them to be stored in surface sites, the actinides and long-life fission products being respectively recycled and concentrated into reduced volumes. The removal of the actinides is done by means of an Octyl N.N Diisobutyl Carbamoyl Methyl Phosphine Oxyde (C.M.P.O.) based liquid membrane, whereas the removal of the caesium and strontium involves crown ethers. Supported liquid membranes (S.L.M.s) have the advantage of implementing very small quantities of extractant, but, they generally have poor stability. The extractant, the diluent and the phase modifier that constitute the organic phase impregnating the membrane play a vital role in SLM stability; the support also affects stability by its nature and geometry. For the extraction of strontium, DtBu 18 C6 enables higher strontium transfer kinetics to be attained than with DC18 C6. As regards caesium, nDec B21 C7 is the most efficient. Unlike strontium, caesium cannot be quantitatively removed, due to the competition of sodium ions in the concentrate. Stable membranes are obtained with DC18 C6 or DtBu18 C6 diluted in alkylbenzene with an added phase modifier such as decanol or isotridecanol. The highest strontium transfer kinetics were obtained with the DC18 C6/hexylbenzene/isotridecanol mixture

  20. Office of Emergency Transportation: Mission and Function

    Energy Technology Data Exchange (ETDEWEB)

    Barry, G W

    1983-08-01

    The Department of Transportation's Office of Emergency Transportation (OET) provides emergency resource management planning for civil transportation in crisis situations. Crises, including the worst-case emergency, war, require management of the department's operating elements: the U.S. Coast Guard, the Federal Aviation Administration, the Urban Mass Transportation Administration, and the Maritime Administration, and coordination with outside transportation agencies. The latter include the Interstate Commerce Commission, the Civil Aeronautics Board, the Corps of Engineers, the Civil Works Rivers and Harbors Division, and the Tennessee Valley Authority. During the 1979 energy crisis, OET served as a communications center to facilitate the national movement of fuel for all transportation modes.