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Sample records for dismantles microtubule networks

  1. Microtubules: A network for solitary waves

    Directory of Open Access Journals (Sweden)

    Zdravković Slobodan

    2017-01-01

    Full Text Available In the present paper we deal with nonlinear dynamics of microtubules. The structure and role of microtubules in cells are explained as well as one of models explaining their dynamics. Solutions of the crucial nonlinear differential equation depend on used mathematical methods. Two commonly used procedures, continuum and semi-discrete approximations, are explained. These solutions are solitary waves usually called as kink solitons, breathers and bell-type solitons. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III45010

  2. Tau can switch microtubule network organizations: from random networks to dynamic and stable bundles.

    Science.gov (United States)

    Prezel, Elea; Elie, Auréliane; Delaroche, Julie; Stoppin-Mellet, Virginie; Bosc, Christophe; Serre, Laurence; Fourest-Lieuvin, Anne; Andrieux, Annie; Vantard, Marylin; Arnal, Isabelle

    2018-01-15

    In neurons, microtubule networks alternate between single filaments and bundled arrays under the influence of effectors controlling their dynamics and organization. Tau is a microtubule bundler that stabilizes microtubules by stimulating growth and inhibiting shrinkage. The mechanisms by which tau organizes microtubule networks remain poorly understood. Here, we studied the self-organization of microtubules growing in the presence of tau isoforms and mutants. The results show that tau's ability to induce stable microtubule bundles requires two hexapeptides located in its microtubule-binding domain and is modulated by its projection domain. Site-specific pseudophosphorylation of tau promotes distinct microtubule organizations: stable single microtubules, stable bundles, or dynamic bundles. Disease-related tau mutations increase the formation of highly dynamic bundles. Finally, cryo-electron microscopy experiments indicate that tau and its variants similarly change the microtubule lattice structure by increasing both the protofilament number and lattice defects. Overall, our results uncover novel phosphodependent mechanisms governing tau's ability to trigger microtubule organization and reveal that disease-related modifications of tau promote specific microtubule organizations that may have a deleterious impact during neurodegeneration. © 2018 Prezel, Elie, et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  3. An ELMO2-RhoG-ILK network modulates microtubule dynamics.

    Science.gov (United States)

    Jackson, Bradley C; Ivanova, Iordanka A; Dagnino, Lina

    2015-07-15

    ELMO2 belongs to a family of scaffold proteins involved in phagocytosis and cell motility. ELMO2 can simultaneously bind integrin-linked kinase (ILK) and RhoG, forming tripartite ERI complexes. These complexes are involved in promoting β1 integrin-dependent directional migration in undifferentiated epidermal keratinocytes. ELMO2 and ILK have also separately been implicated in microtubule regulation at integrin-containing focal adhesions. During differentiation, epidermal keratinocytes cease to express integrins, but ERI complexes persist. Here we show an integrin-independent role of ERI complexes in modulation of microtubule dynamics in differentiated keratinocytes. Depletion of ERI complexes by inactivating the Ilk gene in these cells reduces microtubule growth and increases the frequency of catastrophe. Reciprocally, exogenous expression of ELMO2 or RhoG stabilizes microtubules, but only if ILK is also present. Mechanistically, activation of Rac1 downstream from ERI complexes mediates their effects on microtubule stability. In this pathway, Rac1 serves as a hub to modulate microtubule dynamics through two different routes: 1) phosphorylation and inactivation of the microtubule-destabilizing protein stathmin and 2) phosphorylation and inactivation of GSK-3β, which leads to the activation of CRMP2, promoting microtubule growth. At the cellular level, the absence of ERI species impairs Ca(2+)-mediated formation of adherens junctions, critical to maintaining mechanical integrity in the epidermis. Our findings support a key role for ERI species in integrin-independent stabilization of the microtubule network in differentiated keratinocytes. © 2015 Jackson et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  4. Actin and microtubule networks contribute differently to cell response for small and large strains

    Science.gov (United States)

    Kubitschke, H.; Schnauss, J.; Nnetu, K. D.; Warmt, E.; Stange, R.; Kaes, J.

    2017-09-01

    Cytoskeletal filaments provide cells with mechanical stability and organization. The main key players are actin filaments and microtubules governing a cell’s response to mechanical stimuli. We investigated the specific influences of these crucial components by deforming MCF-7 epithelial cells at small (≤5% deformation) and large strains (>5% deformation). To understand specific contributions of actin filaments and microtubules, we systematically studied cellular responses after treatment with cytoskeleton influencing drugs. Quantification with the microfluidic optical stretcher allowed capturing the relative deformation and relaxation of cells under different conditions. We separated distinctive deformational and relaxational contributions to cell mechanics for actin and microtubule networks for two orders of magnitude of drug dosages. Disrupting actin filaments via latrunculin A, for instance, revealed a strain-independent softening. Stabilizing these filaments by treatment with jasplakinolide yielded cell softening for small strains but showed no significant change at large strains. In contrast, cells treated with nocodazole to disrupt microtubules displayed a softening at large strains but remained unchanged at small strains. Stabilizing microtubules within the cells via paclitaxel revealed no significant changes for deformations at small strains, but concentration-dependent impact at large strains. This suggests that for suspended cells, the actin cortex is probed at small strains, while at larger strains; the whole cell is probed with a significant contribution from the microtubules.

  5. Microtubule catastrophe and rescue.

    Science.gov (United States)

    Gardner, Melissa K; Zanic, Marija; Howard, Jonathon

    2013-02-01

    Microtubules are long cylindrical polymers composed of tubulin subunits. In cells, microtubules play an essential role in architecture and motility. For example, microtubules give shape to cells, serve as intracellular transport tracks, and act as key elements in important cellular structures such as axonemes and mitotic spindles. To accomplish these varied functions, networks of microtubules in cells are very dynamic, continuously remodeling through stochastic length fluctuations at the ends of individual microtubules. The dynamic behavior at the end of an individual microtubule is termed 'dynamic instability'. This behavior manifests itself by periods of persistent microtubule growth interrupted by occasional switching to rapid shrinkage (called microtubule 'catastrophe'), and then by switching back from shrinkage to growth (called microtubule 'rescue'). In this review, we summarize recent findings which provide new insights into the mechanisms of microtubule catastrophe and rescue, and discuss the impact of these findings in regards to the role of microtubule dynamics inside of cells. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Disruption of microtubule network rescues aberrant actin comets in dynamin2-depleted cells.

    Directory of Open Access Journals (Sweden)

    Yuji Henmi

    Full Text Available A large GTPase dynamin, which is required for endocytic vesicle formation, regulates the actin cytoskeleton through its interaction with cortactin. Dynamin2 mutants impair the formation of actin comets, which are induced by Listeria monocytogenes or phosphatidylinositol-4-phosphate 5-kinase. However, the role of dynamin2 in the regulation of the actin comet is still unclear. Here we show that aberrant actin comets in dynamin2-depleted cells were rescued by disrupting of microtubule networks. Depletion of dynamin2, but not cortactin, significantly reduced the length and the speed of actin comets induced by Listeria. This implies that dynamin2 may regulate the actin comet in a cortactin-independent manner. As dynamin regulates microtubules, we investigated whether perturbation of microtubules would rescue actin comet formation in dynamin2-depleted cells. Treatment with taxol or colchicine created a microtubule-free space in the cytoplasm, and made no difference between control and dynamin2 siRNA cells. This suggests that the alteration of microtubules by dynamin2 depletion reduced the length and the speed of the actin comet.

  7. Microtubule-Organizing Centers.

    Science.gov (United States)

    Wu, Jingchao; Akhmanova, Anna

    2017-10-06

    The organization of microtubule networks is crucial for controlling chromosome segregation during cell division, for positioning and transport of different organelles, and for cell polarity and morphogenesis. The geometry of microtubule arrays strongly depends on the localization and activity of the sites where microtubules are nucleated and where their minus ends are anchored. Such sites are often clustered into structures known as microtubule-organizing centers, which include the centrosomes in animals and spindle pole bodies in fungi. In addition, other microtubules, as well as membrane compartments such as the cell nucleus, the Golgi apparatus, and the cell cortex, can nucleate, stabilize, and tether microtubule minus ends. These activities depend on microtubule-nucleating factors, such as γ-tubulin-containing complexes and their activators and receptors, and microtubule minus end-stabilizing proteins with their binding partners. Here, we provide an overview of the current knowledge on how such factors work together to control microtubule organization in different systems.

  8. The polarity protein Par6 is coupled to the microtubule network during molluscan early embryogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Homma, Taihei [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Shimizu, Miho [Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Kuroda, Reiko, E-mail: ckuroda@mail.ecc.u-tokyo.ac.jp [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

    2011-01-07

    Research highlights: {yields} The cDNAs encoding Par6 and aPKC homologues were cloned from the snail Lymnaea stagnalis. {yields} L. stagnalis Par6 directly interacts with tubulin and microtubules and localizes to the microtubule cytoskeleton during the early embryogenesis. {yields} Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of body handedness. -- Abstract: Cell polarity, which directs the orientation of asymmetric cell division and segregation of fate determinants, is a fundamental feature of development and differentiation. Regulators of polarity have been extensively studied, and the critical importance of the Par (partitioning-defective) complex as the polarity machinery is now recognized in a wide range of eukaryotic systems. The Par polarity module is evolutionarily conserved, but its mechanism and cooperating factors vary among different systems. Here we describe the cloning and characterization of a pond snail Lymnaea stagnalis homologue of partitioning-defective 6 (Lspar6). The protein product LsPar6 shows high affinity for microtubules and localizes to the mitotic apparatus during embryonic cell division. In vitro assays revealed direct binding of LsPar6 to tubulin and microtubules, which is the first evidence of the direct interaction between the two proteins. The interaction is mediated by two distinct regions of LsPar6 both located in the N-terminal half. Atypical PKC, a functional partner of Par6, was also found to localize to the mitotic spindle. These results suggest that the L. stagnalis Par complex employs the microtubule network in cell polarity processes during the early embryogenesis. Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of handedness.

  9. The polarity protein Par6 is coupled to the microtubule network during molluscan early embryogenesis

    International Nuclear Information System (INIS)

    Homma, Taihei; Shimizu, Miho; Kuroda, Reiko

    2011-01-01

    Research highlights: → The cDNAs encoding Par6 and aPKC homologues were cloned from the snail Lymnaea stagnalis. → L. stagnalis Par6 directly interacts with tubulin and microtubules and localizes to the microtubule cytoskeleton during the early embryogenesis. → Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of body handedness. -- Abstract: Cell polarity, which directs the orientation of asymmetric cell division and segregation of fate determinants, is a fundamental feature of development and differentiation. Regulators of polarity have been extensively studied, and the critical importance of the Par (partitioning-defective) complex as the polarity machinery is now recognized in a wide range of eukaryotic systems. The Par polarity module is evolutionarily conserved, but its mechanism and cooperating factors vary among different systems. Here we describe the cloning and characterization of a pond snail Lymnaea stagnalis homologue of partitioning-defective 6 (Lspar6). The protein product LsPar6 shows high affinity for microtubules and localizes to the mitotic apparatus during embryonic cell division. In vitro assays revealed direct binding of LsPar6 to tubulin and microtubules, which is the first evidence of the direct interaction between the two proteins. The interaction is mediated by two distinct regions of LsPar6 both located in the N-terminal half. Atypical PKC, a functional partner of Par6, was also found to localize to the mitotic spindle. These results suggest that the L. stagnalis Par complex employs the microtubule network in cell polarity processes during the early embryogenesis. Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of handedness.

  10. Microtubule Catastrophe and Rescue

    OpenAIRE

    Gardner, Melissa K.; Zanic, Marija; Howard, Jonathon

    2012-01-01

    Microtubules are long cylindrical polymers composed of tubulin subunits. In cells, microtubules play an essential role in architecture and motility. For example, microtubules give shape to cells, serve as intracellular transport tracks, and act as key elements in important cellular structures such as axonemes and mitotic spindles. To accomplish these varied functions, networks of microtubules in cells are very dynamic, continuously remodeling through stochastic length fluctuations at the ends...

  11. National School of Dismantling

    International Nuclear Information System (INIS)

    Ivaldi, Fabienne

    2003-01-01

    The National Institut of Nuclear Sciences and Techniques founded of 2001 a National School of Dismantling, NSD, at the end, which was validated by CEA, COGEMA, EDF and ANDRA. This school addresses four major issues: Decontamination; Dismantling; Demolition and waste Disposal (4D). Dedicated for instructing scientific and technical knowledge and know-how, needed in dismantling the nuclear installations, NSD has as targets: - personnel at engineering and operational level; - personnel occupied with involved trades from conception through intervention; - students and employees on leave; - employees while training on the job. Initial basic education for students in collaboration with schools and universities concerns: - master degree in radioactive waste management; - master degree in dismantling; - professional license in 3 D; - pro 4 D graduation. NSD is also engaged in continual formation for employees qualified, or not, adapted to the needs generated by the following tasks and personnel: - introduction in dismantling; - project team; - specialist engineer; - team head; - agent for remedial action; - agent for dismantling. The National School of Dismantling joins a network of human and technological capabilities confined within the 4 D frame, namely: - scientific and technical competencies (experts, instructors working in the nuclear field and dismantling); - pedagogical competence (professionals from basic and continual education); - specific material means such as those used by construction site schools, mock-ups, rooms for practical training etc

  12. Dynamic release of nuclear RanGTP triggers TPX2-dependent microtubule assembly during the apoptotic execution phase.

    Science.gov (United States)

    Moss, David K; Wilde, Andrew; Lane, Jon D

    2009-03-01

    During apoptosis, the interphase microtubule network is dismantled then later replaced by a novel, non-centrosomal microtubule array. These microtubules assist in the peripheral redistribution of nuclear fragments in the apoptotic cell; however, the regulation of apoptotic microtubule assembly is not understood. Here, we demonstrate that microtubule assembly depends upon the release of nuclear RanGTP into the apoptotic cytoplasm because this process is blocked in apoptotic cells overexpressing dominant-negative GDP-locked Ran (T24N). Actin-myosin-II contractility provides the impetus for Ran release and, consequently, microtubule assembly is blocked in blebbistatin- and Y27632-treated apoptotic cells. Importantly, the spindle-assembly factor TPX2 (targeting protein for Xklp2), colocalises with apoptotic microtubules, and siRNA silencing of TPX2, but not of the microtubule motors Mklp1 and Kid, abrogates apoptotic microtubule assembly. These data provide a molecular explanation for the assembly of the apoptotic microtubule network, and suggest important similarities with the process of RanGTP- and TPX2-mediated mitotic spindle formation.

  13. Dismantling techniques

    International Nuclear Information System (INIS)

    Wiese, E.

    1998-01-01

    Most of the dismantling techniques used in a Decontamination and Dismantlement (D and D) project are taken from conventional demolition practices. Some modifications to the techniques are made to limit exposure to the workers or to lessen the spread of contamination to the work area. When working on a D and D project, it is best to keep the dismantling techniques and tools as simple as possible. The workers will be more efficient and safer using techniques that are familiar to them. Prior experience with the technique or use of mock-ups is the best way to keep workers safe and to keep the project on schedule

  14. Dismantling techniques

    Energy Technology Data Exchange (ETDEWEB)

    Wiese, E.

    1998-03-13

    Most of the dismantling techniques used in a Decontamination and Dismantlement (D and D) project are taken from conventional demolition practices. Some modifications to the techniques are made to limit exposure to the workers or to lessen the spread of contamination to the work area. When working on a D and D project, it is best to keep the dismantling techniques and tools as simple as possible. The workers will be more efficient and safer using techniques that are familiar to them. Prior experience with the technique or use of mock-ups is the best way to keep workers safe and to keep the project on schedule.

  15. Characterization and impact of incandescent particles in the ventilation networks during dismantling operations

    International Nuclear Information System (INIS)

    Marchal, Pierre

    2014-01-01

    Fire hazards while metal cutting on dismantling operations led IRSN to focus a study on incandescent particles emitted by these cutting tools and their impact on air filter. If micronic particles (≤ 10 μm) have been studied for their negative impact on human health, few studies are dealing with incandescent particles, despite their strong thermal energy. These particles are mainly made of iron, coming from the metal cutting, and the exothermic oxidation reaction coupled to a high temperature emission causes them to molt. An experimental system was designed, representative of dismantling operations with instrumentations adapted for in-flight particles measurement, such as size, velocity and temperature. The particles are characterized from the emission source (automated cut-off grinder) and all along their path into the ventilation duct to their impact on a filter. An analytical approach of the impact of these particles on the filter shows that the temperature of the particles, greater than 430 C damages the filter medium, and may reduce the filter thickness or perforate it, which leads to a decrease of its filtration efficiency determined according to the French standard. Comparison between the characteristics of the particles and the filtration efficiency has permitted to establish empirical correlations in order to predict the loss of filtration efficiency versus the cutting parameters and some good practices have been proposed to protect the filter. (author)

  16. Characterization of the CLASP2 Protein Interaction Network Identifies SOGA1 as a Microtubule-Associated Protein

    DEFF Research Database (Denmark)

    Sørensen, Rikke Kruse; Krantz, James; Barker, Natalie

    2017-01-01

    . The GTPase-activating proteins AGAP1 and AGAP3 were also enriched in the CLASP2 interactome, although subsequent AGAP3 and CLIP2 interactome analysis suggests a preference of AGAP3 for CLIP2. Follow-up MARK2 interactome analysis confirmed reciprocal co-IP of CLASP2 and also revealed MARK2 can co-IP SOGA1......, glycogen synthase, and glycogenin. Investigating the SOGA1 interactome confirmed SOGA1 can reciprocal co-IP both CLASP2 and MARK2 as well as glycogen synthase and glycogenin. SOGA1 was confirmed to colocalize with CLASP2 and also with tubulin, which identifies SOGA1 as a new microtubule-associated protein....... These results introduce the metabolic function of these proposed novel protein networks and their relationship with microtubules as new fields of cytoskeleton-associated protein biology....

  17. PMA synergistically enhances apicularen A-induced cytotoxicity by disrupting microtubule networks in HeLa cells

    International Nuclear Information System (INIS)

    Seo, Kang-Sik; Hwang, Byung-Doo; Kim, Jong-Seok; Park, Ji-Hoon; Song, Kyoung-Sub; Yun, Eun-Jin; Park, Jong-Il; Kweon, Gi Ryang; Yoon, Wan-Hee; Lim, Kyu

    2014-01-01

    Combination therapy is key to improving cancer treatment efficacy. Phorbol 12-myristate 13-acetate (PMA), a well-known PKC activator, increases the cytotoxicity of several anticancer drugs. Apicularen A induces cytotoxicity in tumor cells through disrupting microtubule networks by tubulin down-regulation. In this study, we examined whether PMA increases apicularen A-induced cytotoxicity in HeLa cells. Cell viability was examined by thiazolyl blue tetrazolium (MTT) assays. To investigate apoptotic potential of apicularen A, DNA fragmentation assays were performed followed by extracting genomic DNA, and caspase-3 activity assays were performed by fluorescence assays using fluorogenic substrate. The cell cycle distribution induced by combination with PMA and apicularen A was examined by flow cytometry after staining with propidium iodide (PI). The expression levels of target proteins were measured by Western blotting analysis using specific antibodies, and α-tubulin mRNA levels were assessed by reverse transcription polymerase chain reaction (RT-PCR). To examine the effect of combination of PMA and apicularen A on the microtubule architecture, α-tubulin protein and nuclei were visualized by immunofluorescence staining using an anti-α-tubulin antibody and PI, respectively. We found that apicularen A induced caspase-dependent apoptosis in HeLa cells. PMA synergistically increased cytotoxicity and apoptotic sub-G 1 population induced by apicularen A. These effects were completely blocked by the PKC inhibitors Ro31-8220 and Go6983, while caspase inhibition by Z-VAD-fmk did not prevent cytotoxicity. RNA interference using siRNA against PKCα, but not PKCβ and PKCγ, inhibited cytotoxicity induced by combination PMA and apicularen A. PMA increased the apicularen A-induced disruption of microtubule networks by further decreasing α- and β-tubulin protein levels in a PKC-dependent manner. These results suggest that the synergy between PMA and apicularen A is involved by

  18. The challenges of dismantling

    International Nuclear Information System (INIS)

    Sene, Monique; Lheureux, Yves; Leroyer, Veronique; Rollinger, Francois; Gauthier, Florence; Depauw, Denis; Reynal, Nathalie; Fraysse, Thierry; Burger, Eric; Bertrand, Adrien; Vallat, Christophe; Bernet, Philippe; Eimer, Michel; Boutin, Dominique; Bietrix, Philippe; Richard, Francoise; Piketty, Laurence; Mouchet, Chantal; Charre, Jean-Pierre

    2014-01-01

    This document gathers Power Point presentations which address the contexts and challenges of dismantling (legal framework, safety and radiation protection challenges, waste processing industry), and propose illustrations of dismantling challenges (example of operations to prepare EURODIF dismantling and CLIGEET work-group on EURODIF dismantling, examples of dismantling of EDF installations and CLIs' opinion on the dismantling of EDF installations, Brennilis dismantling follow-up performed by the CLI, examples of dismantling of CEA installations and opinion of a CLI on the dismantling of CEA installations)

  19. Vitamin K3 disrupts the microtubule networks by binding to tubulin: a novel mechanism of its antiproliferative activity.

    Science.gov (United States)

    Acharya, Bipul R; Choudhury, Diptiman; Das, Amlan; Chakrabarti, Gopal

    2009-07-28

    Vitamin K3 (2-methyl-1,4-naphthoquinone), also known as menadione, is the synthetic precursor of all the naturally occurring vitamin K in the body. Vitamin K is necessary for the production of prothrombin and five other blood-clotting factors in humans. We have examined the effects of menadione on cellular microtubules ex vivo as well as its binding with purified tubulin and microtubules in vitro. Cell viability experiments using human cervical epithelial cancer cells (HeLa) and human oral epithelial cancer cells (KB) indicated that the IC(50) values for menadione are 25.6 +/- 0.6 and 64.3 +/- 0.36 microM, respectively, in those cells. Mendione arrests HeLa cells in mitosis. Immunofluorescence studies using an anti-alpha-tubulin antibody showed a significant irreversible depolymeriztion of the interphase microtubule network and spindle microtubule in a dose-dependent manner. In vitro polymerization of purified tubulin into microtubules is inhibited by menadione with an IC(50) value of 47 +/- 0.65 microM. The binding of menadione with tubulin was studied using menadione fluorescence and intrinsic tryptophan fluorescence of tubulin. Binding of menadione to tubulin is slow, taking 35 min for equilibration at 25 degrees C. The association reaction kinetics is biphasic in nature, and the association rate constants for fast and slow phases are 189.12 +/- 17 and 32.44 +/- 21 M(-1) s(-1) at 25 degrees C, respectively. The stoichiometry of menadione binding to tubulin is 1:1 (molar ratio) with a dissociation constant from 2.44 +/- 0.34 to 3.65 +/- 0.25 microM at 25 degrees C. Menadione competes for the colchicine binding site with a K(i) of 2.5 muM as determined from a modified Dixon plot. The obtained data suggested that menadione binds at the colchicine binding site to tubulin. Thus, we can conclude one novel mechanism of inhibition of cancer cell proliferation by menadione is through tubulin binding.

  20. Specific chlamydial inclusion membrane proteins associate with active Src family kinases in microdomains that interact with the host microtubule network.

    Science.gov (United States)

    Mital, Jeffrey; Miller, Natalie J; Fischer, Elizabeth R; Hackstadt, Ted

    2010-09-01

    Chlamydiae are Gram-negative obligate intracellular bacteria that cause diseases with significant medical and economic impact. Chlamydia trachomatis replicates within a vacuole termed an inclusion, which is extensively modified by the insertion of a number of bacterial effector proteins known as inclusion membrane proteins (Incs). Once modified, the inclusion is trafficked in a dynein-dependent manner to the microtubule-organizing centre (MTOC), where it associates with host centrosomes. Here we describe a novel structure on the inclusion membrane comprised of both host and bacterial proteins. Members of the Src family of kinases are recruited to the chlamydial inclusion in an active form. These kinases display a distinct, localized punctate microdomain-like staining pattern on the inclusion membrane that colocalizes with four chlamydial inclusion membrane proteins (Incs) and is enriched in cholesterol. Biochemical studies show that at least two of these Incs stably interact with one another. Furthermore, host centrosomes associate with these microdomain proteins in C. trachomatis-infected cells and in uninfected cells exogenously expressing one of the chlamydial effectors. Together, the data suggest that a specific structure on the C. trachomatis inclusion membrane may be responsible for the known interactions of chlamydiae with the microtubule network and resultant effects on centrosome stability.

  1. Shaping the tracks : Regulation of microtubule dynamics by kinesins KIF21A and KIF21B

    NARCIS (Netherlands)

    van Riel, W.E.|info:eu-repo/dai/nl/338772634

    2016-01-01

    Control of microtubule dynamics is important for cell morphogenesis. Kinesins, motor proteins known to function in cargo transport, were recently also implicated in altering the microtubule network. Several kinesins are described to cause microtubule network reorganization or stabilization, either

  2. Dismantling technologies trends

    International Nuclear Information System (INIS)

    Devaux, P.

    2009-01-01

    In this work dismantling technologies trends realized by the CEA are reviewed. There following technologies are presented: Data acquisition from facilities; Scenario studies; Remote handling and carriers; Dismantling techniques; Decontamination.

  3. Determining the structure-mechanics relationships of dense microtubule networks with confocal microscopy and magnetic tweezers-based microrheology.

    Science.gov (United States)

    Yang, Yali; Valentine, Megan T

    2013-01-01

    The microtubule (MT) cytoskeleton is essential in maintaining the shape, strength, and organization of cells. Its spatiotemporal organization is fundamental for numerous dynamic biological processes, and mechanical stress within the MT cytoskeleton provides an important signaling mechanism in mitosis and neural development. This raises important questions about the relationships between structure and mechanics in complex MT structures. In vitro, reconstituted cytoskeletal networks provide a minimal model of cell mechanics while also providing a testing ground for the fundamental polymer physics of stiff polymer gels. Here, we describe our development and implementation of a broad tool kit to study structure-mechanics relationships in reconstituted MT networks, including protocols for the assembly of entangled and cross-linked MT networks, fluorescence imaging, microstructure characterization, construction and calibration of magnetic tweezers devices, and mechanical data collection and analysis. In particular, we present the design and assembly of three neodymium iron boron (NdFeB)-based magnetic tweezers devices optimized for use with MT networks: (1) high-force magnetic tweezers devices that enable the application of nano-Newton forces and possible meso- to macroscale materials characterization; (2) ring-shaped NdFeB-based magnetic tweezers devices that enable oscillatory microrheology measurements; and (3) portable magnetic tweezers devices that enable direct visualization of microscale deformation in soft materials under applied force. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. EDF's dismantling experience

    International Nuclear Information System (INIS)

    Mira, J.J.

    1993-01-01

    The dismantling policy at EDF, taking into account technical, economical and socio-political factors, is presented. The various current realizations are reviewed and their dismantling solution discussed: Chinon A2, Chinon A1, Marcoule G1, G2, G3, Brennilis (EL4). Several dismantling projects are also described (Chinon A3, St-Laurent A1-A2, Chooz A). The various dismantling operations are presented and scheduled

  5. Supramolecular assembly of biological molecules purified from bovine nerve cells: from microtubule bundles and necklaces to neurofilament networks

    International Nuclear Information System (INIS)

    Needleman, Daniel J; Jones, Jayna B; Raviv, Uri; Ojeda-Lopez, Miguel A; Miller, H P; Li, Y; Wilson, L; Safinya, C R

    2005-01-01

    With the completion of the human genome project, the biosciences community is beginning the daunting task of understanding the structures and functions of a large number of interacting biological macromolecules. Examples include the interacting molecules involved in the process of DNA condensation during the cell cycle, and in the formation of bundles and networks of filamentous actin proteins in cell attachment, motility and cytokinesis. In this proceedings paper we present examples of supramolecular assembly based on proteins derived from the vertebrate nerve cell cytoskeleton. The axonal cytoskeleton in vertebrate neurons provides a rich example of bundles and networks of neurofilaments, microtubules (MTs) and filamentous actin, where the nature of the interactions, structures, and structure-function correlations remains poorly understood. We describe synchrotron x-ray diffraction, electron microscopy, and optical imaging data, in reconstituted protein systems purified from bovine central nervous system, which reveal unexpected structures not predicted by current electrostatic theories of polyelectrolyte bundling, including three-dimensional MT bundles and two-dimensional MT necklaces

  6. Dismantling of nuclear facilities

    International Nuclear Information System (INIS)

    Tallec, M.; Kus, J.P.

    2009-01-01

    Nuclear facilities have a long estimable lifetime but necessarily limited in time. At the end of their operation period, basic nuclear installations are the object of cleansing operations and transformations that will lead to their definitive decommissioning and then to their dismantling. Because each facility is somewhere unique, cleansing and dismantling require specific techniques. The dismantlement consists in the disassembly and disposing off of big equipments, in the elimination of radioactivity in all rooms of the facility, in the demolition of buildings and eventually in the reconversion of all or part of the facility. This article describes these different steps: 1 - dismantling strategy: main de-construction guidelines, expected final state; 2 - industries and sites: cleansing and dismantling at the CEA, EDF's sites under de-construction; 3 - de-construction: main steps, definitive shutdown, preparation of dismantling, electromechanical dismantling, cleansing/decommissioning, demolition, dismantling taken into account at the design stage, management of polluted soils; 4 - waste management: dismantlement wastes, national policy of radioactive waste management, management of dismantlement wastes; 5 - mastery of risks: risk analysis, conformability of risk management with reference documents, main risks encountered at de-construction works; 6 - regulatory procedures; 7 - international overview; 8 - conclusion. (J.S.)

  7. Challenges of dismantling

    International Nuclear Information System (INIS)

    Chevet, P.F.; Schilz, F.; Rondeau, J.M.; Piketty, L.; Dupraz, B.; Conte, D.; Duguey, M.; Louet, C.A.; Dorison, A.; Dutzer, M.; Boucau, J.; Eimer, M.; Boutin, D.; Revilla, J.L.; Golshan, M.; Smith, G.

    2015-01-01

    This document is made up of short articles whose issue is reactor dismantling. The first article presents the French strategy that can be featured by immediate dismantling (the dismantling process is prepared a long time before decommissioning and begins as soon as the reactor is shut down) and massive dismantling (a lot of nuclear facilities will be decommissioned in a near future). The following 4 articles give the viewpoints of ASN (Nuclear Safety Authority), EDF (for its fleet of PWRs), CEA (for its experimental reactors and nuclear facilities) and AREVA (for the EURODIF George Besse plant). Costs and financing are dealt with in an article that says that the cost is greatly dependent on the final state: a complete nuclear-free area or an area whose radioactivity is below safe standards and that law implies to constitute provisions all along the operating life of the facility to cover dismantling costs. Dismantling generates a huge amount of very low-level radioactive wastes particularly metal scraps that might be recycled and get out of nuclear industry, an article details the feasibility of such recycling. Another article shows the impact of massive dismantling on the management of radioactive wastes. In an article Westinghouse presents its experience in the cutting of internal equipment of the reactor core. The last 2 articles presents the dismantling strategies in Spain and in the UK. (A.C.)

  8. The Superphenix dismantling

    International Nuclear Information System (INIS)

    Carle, R.

    1999-01-01

    This document presents selected abstracts of Remy Carle's presentation on the dismantling of Superphenix (october 1998). The author wonders about the consequences of such a decision. After a chronological account of this fast reactor project, its cost and the scientific and technical contribution, the dismantling problem is considered. For EDF (Electricite De France) the dismantling dimension is considered at the same time of the design. The main problem is the liquid sodium reprocessing: a technical but also a financing problem. The end of the speech deals with the political aspects of Superphenix and the relations with the public. (A.L.B.)

  9. Some regulation aspects in dismantling

    International Nuclear Information System (INIS)

    Niel, J.C.

    1993-01-01

    In the French regulation framework, operations linked to dismantling are controlled by an overall technical and legislative system applied to all the different stages of the facility (commissioning, etc.). Government control on facilities under dismantling is aimed at dismantling operation safety and security, and dismantling waste processing in order to ensure public and environmental protection

  10. The NFL-TBS.40-63 anti-glioblastoma peptide disrupts microtubule and mitochondrial networks in the T98G glioma cell line.

    Directory of Open Access Journals (Sweden)

    Romain Rivalin

    Full Text Available Despite aggressive therapies, including combinations of surgery, radiotherapy and chemotherapy, glioblastoma remains a highly aggressive brain cancer with the worst prognosis of any central nervous system disease. We have previously identified a neurofilament-derived cell-penetrating peptide, NFL-TBS.40-63, that specifically enters by endocytosis in glioblastoma cells, where it induces microtubule destruction and inhibits cell proliferation. Here, we explore the impact of NFL-TBS.40-63 peptide on the mitochondrial network and its functions by using global cell respiration, quantitative PCR analysis of the main actors directing mitochondrial biogenesis, western blot analysis of the oxidative phosphorylation (OXPHOS subunits and confocal microscopy. We show that the internalized peptide disturbs mitochondrial and microtubule networks, interferes with mitochondrial dynamics and induces a rapid depletion of global cell respiration. This effect may be related to reduced expression of the NRF-1 transcription factor and of specific miRNAs, which may impact mitochondrial biogenesis, in regard to default mitochondrial mobility.

  11. TCTEX1D4, a novel protein phosphatase 1 interactor: connecting the phosphatase to the microtubule network

    Science.gov (United States)

    Korrodi-Gregório, Luís; Vieira, Sandra I.; Esteves, Sara L. C.; Silva, Joana V.; Freitas, Maria João; Brauns, Ann-Kristin; Luers, Georg; Abrantes, Joana; Esteves, Pedro J.; da Cruz e Silva, Odete A. B.; Fardilha, Margarida; da Cruz e Silva, Edgar F.

    2013-01-01

    Summary Reversible phosphorylation plays an important role as a mechanism of intracellular control in eukaryotes. PPP1, a major eukaryotic Ser/Thr-protein phosphatase, acquires its specificity by interacting with different protein regulators, also known as PPP1 interacting proteins (PIPs). In the present work we characterized a physiologically relevant PIP in testis. Using a yeast two-hybrid screen with a human testis cDNA library, we identified a novel PIP of PPP1CC2 isoform, the T-complex testis expressed protein 1 domain containing 4 (TCTEX1D4) that has recently been described as a Tctex1 dynein light chain family member. The overlay assays confirm that TCTEX1D4 interacts with the different spliced isoforms of PPP1CC. Also, the binding domain occurs in the N-terminus, where a consensus PPP1 binding motif (PPP1BM) RVSF is present. The distribution of TCTEX1D4 in testis suggests its involvement in distinct functions, such as TGFβ signaling at the blood–testis barrier and acrosome cap formation. Immunofluorescence in human ejaculated sperm shows that TCTEX1D4 is present in the flagellum and in the acrosome region of the head. Moreover, TCTEX1D4 and PPP1 co-localize in the microtubule organizing center (MTOC) and microtubules in cell cultures. Importantly, the TCTEX1D4 PPP1BM seems to be relevant for complex formation, for PPP1 retention in the MTOC and movement along microtubules. These novel results open new avenues to possible roles of this dynein, together with PPP1. In essence TCTEX1D4/PPP1C complex appears to be involved in microtubule dynamics, sperm motility, acrosome reaction and in the regulation of the blood–testis barrier. PMID:23789093

  12. UDIN's dismantling projects

    International Nuclear Information System (INIS)

    Laffaille, C.

    1993-01-01

    The role of UDIN (Central unit for nuclear facility decommissioning) at the CEA is reviewed together with the main specific aspects of nuclear dismantling: the different options and dismantling strategies and costs. The characteristics of the main on-going projects are described: graphite-gas reactors (G2/G3), RAPSODIE (RNR), AT1 (pilot RNR fuel reprocessing plant), ELAN II B (Cesium source conditioning plant), EL4 (heavy water/CO2 reactor), RM2 (fuel control radio-metallurgical laboratory) and UB-UM (Uranium enrichment plant)

  13. The dismantling of nuclear installations

    International Nuclear Information System (INIS)

    Lacoste, A.C.; Duthe, M.; Mignon, H.; Lambert, F.; Pradel, Ph.; Hillewaere, J.P.; Dupre la Tour, St.; Mandil, C.; Weil, L.; Eickelpasch, N.; Finsterwalder, L.

    1997-01-01

    for nuclear installations, the dismantling is an important part of their exploitation. The technology of dismantling is existing and to get a benefit from the radioactive decay, it seems more easy for operating company such E.D.F. to wait for fifty years before dismantling. But in order to get the knowledge of this operation, the Safety Authority wanted to devote this issue of 'Controle'to the dismantling method. This issue includes: the legal aspects, the risks assessment, the dismantling policy at E.D.F., the site of Brennilis (first French experience of dismantling), the dismantling techniques, the first dismantling of a fuel reprocessing plant, comparison with classical installations, economic aspect, some German experiences, the cleansing of the american site of Handford. (N.C.)

  14. LEP dismantling starts

    CERN Multimedia

    2000-01-01

    Since the end of November, various teams have been getting stuck into dismantling the LEP accelerator and its four experiments. After making the installations safe, the dismantling and removal of 40,000 tonnes of equipment is underway. Down in the tunnel, it is a solemn moment. It is 10 o'clock on 13 December and Daniel Regin, one of those heading the dismantling work, moves in on a magnet, armed with a hydraulic machine. Surrounded by teams gathered there for a course in dismantling, he makes the first cut into LEP. The great deconstruction has begun. In little over than a year, the accelerator will have been cleared away to make room for its successor, the LHC. The start of the operation goes back to 27 November. Because before setting about the machine with hydraulic shears and monkey wrenches, LEP had first to be made safe - it was important to make sure the machine could be taken apart without risk. All the SPS beam injection systems to LEP were cut off. The fluids used for cooling the magnets and superc...

  15. Dismantling of Vandellos I

    International Nuclear Information System (INIS)

    Armada, J. R.

    2003-01-01

    Spain is witnessing the phase-out of a nuclear power plant. It is a unique experience in our country and therefore the dismantling work has been watched closely, not only from here but also from abroad. The Empresa Nacional de Residuos Radiactivos (ENRESA) is in charge of managing the dismantling and decommissioning work of the Vandellos-I nuclear power plant, located in the municipality of L'Hospitalet de l'Infant (Tarragona). the work began five years ago and has been executed on schedule. the appearance of what was one of the first Spanish commercial nuclear power plants has been changed radically to leave premises suitable for any other activity. (Author)

  16. Dismantling of nuclear facilities

    International Nuclear Information System (INIS)

    Tallec, Michele; Kus, Jean-Pierre; Mogavero, Robert; Genelot, Gabriel

    2009-01-01

    Although the operational life of nuclear plants is long (around 60 years for French reactors) it is nonetheless limited in time, the stopping of it being essentially due to the obsolescence of materials and processes or to economic or safety considerations. The nuclear power plants are then subjected to cleanup and dismantling operations which have different objectives and require specific techniques. The cleanup and/or dismantling of a nuclear power produces significant quantities of waste which is generally of a different nature to that produced during the operation of the concerned plant. The radioactive waste produced by these operations is destined to be sent to the waste disposal facilities of the French National Agency for the Management of Nuclear Waste. (authors)

  17. Method for dismantling shields

    International Nuclear Information System (INIS)

    Fukuzawa, Rokuro; Kondo, Nobuhiro; Kamiyama, Yoshinori; Kawasato, Ken; Hiraga, Tomoaki.

    1990-01-01

    The object of the present invention is to enable operators to dismantle shieldings contaminated by radioactivity easily and in a short period of time without danger of radiation exposure. A plurality of introduction pipes are embedded previously to the shielding walls of shielding members which contain a reactor core in a state where both ends of the introduction pipes are in communication with the outside. A wire saw is inserted into the introduction pipes to cut the shieldings upon dismantling. Then, shieldings can be dismantled easily in a short period of time with no radiation exposure to operator's. Further, according to the present invention, since the wire saw can be set easily and a large area can be cut at once, operation efficiency is improved. Further, since remote control is possible, cutting can be conducted in water and complicated places of the reactor. Biting upon starting the wire saw in the introduction pipe is reduced to facilitate startup for the rotation. (I.S.)

  18. Brennilis, laboratory of dismantlement

    International Nuclear Information System (INIS)

    Dupin, L.

    2011-01-01

    This article comments some aspects of the dismantlement activity on the Brennilis site (in Brittany) where a heavy water reactor has been operated from 1966 to 1985. Half of the deconstruction work has been performed between 1996 and 2006. As the model proposed by EDF for this operation raised some questions, works have been stopped for a while, until July 2011 when a decree authorized them again, but for some parts of the site only. The reactor block must wait as no technical solution exists for storage. But, the experience from this site will be used for eight other first generation power plants

  19. LEP Dismantling: Wagons Roll!

    CERN Multimedia

    2001-01-01

    The first trucks transporting material from LEP and its four experiments left CERN on 31 January. Since the LEP dismantling operation began, the material had been waiting to be removed from the sites of the four experiments and the special transit area on the Prévessin site. On the evening of 30 January, the French customs authorities gave the green light for the transport operation to begin. So first thing the next day, the two companies in charge of recycling the material, Jaeger & Bosshard (Switzerland) and Excoffier (France), set to work. Only 1500 truckloads to go before everything has been removed!

  20. Dismantling of transuranic contaminated facilities

    International Nuclear Information System (INIS)

    Roux, P.

    1985-01-01

    The dismantling of transuranic contaminated facilities raises specific problems. A large part of these problems relates to the management of the waste resulting from dismantling. From the experience gained in the different centers CEA and COGEMA it appears that there are industrial solutions in the group CEA and that an engineering company such as SGN can export them [fr

  1. Machine for dismantling metal parts

    Energy Technology Data Exchange (ETDEWEB)

    Prokopov, O.I.; Loginovskiy, V.I.; Yagudin, S.Z.

    1982-01-01

    The purpose of the invention is to reduce the outlays of time for dismantling metal parts under conditions of eliminating open gas and oil gushers in operational drilling. This goal is achieved because the machine for dismantling the metal parts is equipped with a set of clamping elements arranged on the chassis, where each of them has a drive.

  2. Neuronal plasticity in hibernation and the proposed role of the microtubule-associated protein tau as a "master switch" regulating synaptic gain in neuronal networks.

    Science.gov (United States)

    Arendt, Thomas; Bullmann, Torsten

    2013-09-01

    The present paper provides an overview of adaptive changes in brain structure and learning abilities during hibernation as a behavioral strategy used by several mammalian species to minimize energy expenditure under current or anticipated inhospitable environmental conditions. One cellular mechanism that contributes to the regulated suppression of metabolism and thermogenesis during hibernation is reversible phosphorylation of enzymes and proteins, which limits rates of flux through metabolic pathways. Reversible phosphorylation during hibernation also affects synaptic membrane proteins, a process known to be involved in synaptic plasticity. This mechanism of reversible protein phosphorylation also affects the microtubule-associated protein tau, thereby generating a condition that in the adult human brain is associated with aggregation of tau protein to paired helical filaments (PHFs), as observed in Alzheimer's disease. Here, we put forward the concept that phosphorylation of tau is a neuroprotective mechanism to escape NMDA-mediated hyperexcitability of neurons that would otherwise occur during slow gradual cooling of the brain. Phosphorylation of tau and its subsequent targeting to subsynaptic sites might, thus, work as a kind of "master switch," regulating NMDA receptor-mediated synaptic gain in a wide array of neuronal networks, thereby enabling entry into torpor. If this condition lasts too long, however, it may eventually turn into a pathological trigger, driving a cascade of events leading to neurodegeneration, as in Alzheimer's disease or other "tauopathies".

  3. Short Linear Sequence Motif LxxPTPh Targets Diverse Proteins to Growing Microtubule Ends

    NARCIS (Netherlands)

    Kumar, Anil; Manatschal, Cristina; Rai, Ankit; Grigoriev, Ilya; Degen, Miriam Steiner; Jaussi, Rolf; Kretzschmar, Ines; Prota, Andrea E; Volkmer, Rudolf; Kammerer, Richard A.; Akhmanova, Anna; Steinmetz, Michel O.

    2017-01-01

    Microtubule plus-end tracking proteins (+TIPs) are involved in virtually all microtubule-based processes. End-binding (EB) proteins are considered master regulators of +TIP interaction networks, since they autonomously track growing microtubule ends and recruit a plethora of proteins to this

  4. Nuclear installations: decommissioning and dismantling

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    This document is a compilation of seven talks given during the 1995 EUROFORUM conference about decommissioning and dismantling of Nuclear installations in the European Community. The first two papers give a detailed description of the legal, financial and regulatory framework of decommissioning and dismantling of nuclear facilities in the European Union and a review of the currently available decommissioning techniques for inventory, disassembly, decontamination, remote operations and management of wastes. Other papers describe some legal and technical aspects of reactor and plants dismantling in UK, Germany, Spain and France. (J.S.)

  5. Technical challenges for dismantlement verification

    International Nuclear Information System (INIS)

    Olinger, C.T.; Stanbro, W.D.; Johnston, R.G.; Nakhleh, C.W.; Dreicer, J.S.

    1997-01-01

    In preparation for future nuclear arms reduction treaties, including any potential successor treaties to START I and II, the authors have been examining possible methods for bilateral warhead dismantlement verification. Warhead dismantlement verification raises significant challenges in the political, legal, and technical arenas. This discussion will focus on the technical issues raised by warhead arms controls. Technical complications arise from several sources. These will be discussed under the headings of warhead authentication, chain-of-custody, dismantlement verification, non-nuclear component tracking, component monitoring, and irreversibility. The authors will discuss possible technical options to address these challenges as applied to a generic dismantlement and disposition process, in the process identifying limitations and vulnerabilities. They expect that these considerations will play a large role in any future arms reduction effort and, therefore, should be addressed in a timely fashion

  6. The promising opportunity of dismantlement

    International Nuclear Information System (INIS)

    Anon.

    2009-01-01

    Civil engineering, mechanics and waste conditioning companies are thriving around the market of nuclear facilities dismantlement which is promised to a huge development in the coming decade. This paper presents a map of the opportunities of the dismantlement market throughout Europe (research and power reactors, fuel fabrication plants, spent fuel reprocessing plants) and a cost estimation of a given dismantling work with respect to the different steps of the work. In France a small core of about twenty companies is involved in nuclear dismantlement but the French market is also looking towards foreign specialists of this activity. The British market is also targeted by the French companies but for all the actors the technological or commercial advance gained today will be determining for the future markets. (J.S.)

  7. Definition of a dismantling project

    International Nuclear Information System (INIS)

    Meyers, H.; Claes, J.; Geens, L.

    1988-01-01

    The shutdown of the fuel reprocessing plant of Eurochemic having been decided, a study for defining the facilities to be dismantled and how to do it, was conducted by Belgoprocess. The cost of the operation was estimated by an accurate investigation and by a pilot project on the dismantling of the wastes storage building. The work carried out up to now and the problems to be solved are summarized [fr

  8. BRET fuel assembly dismantling machine

    International Nuclear Information System (INIS)

    Titzler, P.A.; Bennett, K.L.; Kelley, R.S. Jr.; Stringer, J.L.

    1984-08-01

    An automated remote nuclear fuel assembly milling and dismantling machine has been designed, developed, and demonstrated at the Hanford Engineering Development Laboratory (HEDL) in Richland, Washington. The machine can be used to dismantle irradiated breeder fuel assemblies from the Fast Flux Test Facility prior to fuel reprocessing. It can be installed in an existing remotely operated shielded hot cell facility, the Fuels and Materials Examination Facility (FMEF), at the Hanford Site in Richland, Washington

  9. Microtubule–microtubule sliding by kinesin-1 is essential for normal cytoplasmic streaming in Drosophila oocytes

    Science.gov (United States)

    Lu, Wen; Winding, Michael; Lakonishok, Margot; Wildonger, Jill

    2016-01-01

    Cytoplasmic streaming in Drosophila oocytes is a microtubule-based bulk cytoplasmic movement. Streaming efficiently circulates and localizes mRNAs and proteins deposited by the nurse cells across the oocyte. This movement is driven by kinesin-1, a major microtubule motor. Recently, we have shown that kinesin-1 heavy chain (KHC) can transport one microtubule on another microtubule, thus driving microtubule–microtubule sliding in multiple cell types. To study the role of microtubule sliding in oocyte cytoplasmic streaming, we used a Khc mutant that is deficient in microtubule sliding but able to transport a majority of cargoes. We demonstrated that streaming is reduced by genomic replacement of wild-type Khc with this sliding-deficient mutant. Streaming can be fully rescued by wild-type KHC and partially rescued by a chimeric motor that cannot move organelles but is active in microtubule sliding. Consistent with these data, we identified two populations of microtubules in fast-streaming oocytes: a network of stable microtubules anchored to the actin cortex and free cytoplasmic microtubules that moved in the ooplasm. We further demonstrated that the reduced streaming in sliding-deficient oocytes resulted in posterior determination defects. Together, we propose that kinesin-1 slides free cytoplasmic microtubules against cortically immobilized microtubules, generating forces that contribute to cytoplasmic streaming and are essential for the refinement of posterior determinants. PMID:27512034

  10. The good wealth of dismantlement

    International Nuclear Information System (INIS)

    Maincent, G.

    2009-01-01

    Civil engineering, mechanical and waste conditioning companies are working hard on the market of nuclear facilities dismantling. This market has a great future ahead of it in the ten years to come. According to the European Commission, 50 to 60 reactors among the 157 actually in service in the European Union should be dismantled by 2025. The cost per reactor is estimated to 10-15% of the initial investment, which represents an enormous amount of money, estimated to 20-39 billion euros for the only French nuclear park. In France, this market is shared by a core of about 20 companies, like Spie Nucleaire, Onet, Vinci (Nuvia) and Areva. Some dismantling sites require a specific skill, in particular those in relation with the research activity of the CEA (the French atomic energy commission) or involving specific technologies (research reactors, spent fuel reprocessing plants, sodium-cooled rectors..). (J.S.)

  11. Electrodynamic effects on microtubules

    Czech Academy of Sciences Publication Activity Database

    Kučera, Ondřej; Havelka, Daniel; Deriu, M.A.; Cifra, Michal

    2015-01-01

    Roč. 44, Jul (2015), s. 169-169 ISSN 0175-7571. [10th European-Biophysical-Societies-Association (EBSA) European Biophysics Congress. 18.07.2015-22.07.2015, Dresden] R&D Projects: GA ČR(CZ) GA15-17102S Institutional support: RVO:67985882 Keywords : Microtubules * Electric al polarity Subject RIV: JA - Electronics ; Optoelectronics, Electric al Engineering

  12. Microtubule's conformational cap

    DEFF Research Database (Denmark)

    Flyvbjerg, H.

    1999-01-01

    The molecular mechanisms that allow elongation of the unstable microtubule lattice remain unclear. It is usually thought that the GDP-liganded tubulin lattice is capped by a small layer of GTP- or GDP-P(i)-liganded molecules, the so called "GTP-cap". Here, we point-out that the elastic properties...

  13. Centrosome and microtubule instability in aging Drosophila cells

    Science.gov (United States)

    Schatten, H.; Chakrabarti, A.; Hedrick, J.

    1999-01-01

    Several cytoskeletal changes are associated with aging which includes alterations in muscle structure leading to muscular atrophy, and weakening of the microtubule network which affects cellular secretion and maintenance of cell shape. Weakening of the microtubule network during meiosis in aging oocytes can result in aneuploidy or trisomic zygotes with increasing maternal age. Imbalances of cytoskeletal organization can lead to disease such as Alzheimer's, muscular disorders, and cancer. Because many cytoskeletal diseases are related to age we investigated the effects of aging on microtubule organization in cell cultures of the Drosophila cell model system (Schneider S-1 and Kc23 cell lines). This cell model is increasingly being used as an alternative system to mammalian cell cultures. Drosophila cells are amenable to genetic manipulations and can be used to identify and manipulate genes which are involved in the aging processes. Immunofluorescence, scanning, and transmission electron microscopy were employed for the analysis of microtubule organizing centers (centrosomes) and microtubules at various times after subculturing cells in fresh medium. Our results reveal that centrosomes and the microtubule network becomes significantly affected in aging cells after 5 days of subculture. At 5-14 days of subculture, 1% abnormal out of 3% mitoses were noted which were clearly distinguishable from freshly subcultured control cells in which 3% of cells undergo normal mitosis with bipolar configurations. Microtubules are also affected in the midbody during cell division. The midbody in aging cells becomes up to 10 times longer when compared with midbodies in freshly subcultured cells. During interphase, microtubules are often disrupted and disorganized, which may indicate improper function related to transport of cell organelles along microtubules. These results are likely to help explain some cytoskeletal disorders and diseases related to aging.

  14. The timing of reactor dismantling

    International Nuclear Information System (INIS)

    Roberts, P.

    2000-01-01

    Work has been progressing across the world for the decommissioning of nuclear reactors. The initial work focused on the early, complete dismantling but this was associated with small size reactors and was done for experimental or demonstration purposes. The situation now is that an increasing number of full size power reactors are being shutdown and decision are being made as to the decommissioning strategy to be applied, e.g. with respect to the appropriate timing of reactor dismantling. There are two basic approaches to the timing of reactor dismantling, which are to either proceed with dismantling on an early time scale or to delay it for a period of years. There are a number of examples worldwide of both approaches being taken but one common feature of the approach taken by most countries is that decisions are made on a case by case basis, taking account of relevant factors, and as a result the strategy can vary from reactor to reactor and from country to country. Decisions on timing take account of the following main factors: safety, radioactive decay, financial factors, radioactive waste, reactor type, technology, repository availability, site re-use, regulatory standards, plant knowledge/records, other issues

  15. Dismantling system of concrete thermal shielding walls

    International Nuclear Information System (INIS)

    Machida, Nobuhiro; Saiki, Yoshikuni; Ono, Yorimasa; Tokioka, Masatake; Ogino, Nobuyuki.

    1985-01-01

    Purpose: To enable safety and efficient dismantling of concrete thermal shielding walls in nuclear reactors. Method: Concrete thermal shielding walls are cut and dismantled into dismantled blocks by a plasma cutting tool while sealing the top opening of bioshielding structures. The dismantled blocks are gripped and conveyed. The cutting tool is remote-handled while monitoring on a television receiver. Slugs and dusts produced by cutting are removed to recover. Since the dismantling work is carried out while sealing the working circumstance and by the remote control of the cutting tool, the operators' safety can be secured. Further, since the thermal sealing walls are cut and dismantled into blocks, dismantling work can be done efficiently. (Moriyama, K.)

  16. Synchronous Oscillations in Microtubule Polymerization

    Science.gov (United States)

    Carlier, M. F.; Melki, R.; Pantaloni, D.; Hill, T. L.; Chen, Y.

    1987-08-01

    Under conditions where microtubule nucleation and growth are fast (i.e., high magnesium ion and tubulin concentrations and absence of glycerol), microtubule assembly in vitro exhibits an oscillatory regime preceding the establishment of steady state. The amplitude of the oscillations can represent >50% of the maximum turbidity change and oscillations persist for up to 20 periods of 80 s each. Oscillations are accompanied by extensive length redistribution of microtubules. Preliminary work suggests that the oscillatory kinetics can be simulated using a model in which many microtubules undergo synchronous transitions between growing and rapidly depolymerizing phases, complicated by the kinetically limiting rate of nucleotide exchange on free tubulin.

  17. Simultaneous 3D tracking of passive tracers and microtubule bundles in an active gel

    Science.gov (United States)

    Fan, Yi; Breuer, Kenneth S.; Fluids Team

    Kinesin-driven microtubule bundles generate a spontaneous flow in unconfined geometries. They exhibit properties of active matter, including the emergence of collective motion, reduction of apparent viscosity and consumption of local energy. Here we present results from 3D tracking of passive tracers (using Airy rings and 3D scanning) synchronized with 3D measurement of the microtubule bundles motion. This technique is applied to measure viscosity variation and collective flow in a confined geometry with particular attention paid to the self-pumping system recently reported by Wu et al. (2016). Results show that the viscosity in an equilibrium microtubule network is around half that of the isotropic unbundled microtubule solution. Cross-correlations of the active microtubule network and passive tracers define a neighborhood around microtubule bundles in which passive tracers are effectively transported. MRSEC NSF.

  18. Modeling microtubule oscillations

    DEFF Research Database (Denmark)

    Jobs, E.; Wolf, D.E.; Flyvbjerg, H.

    1997-01-01

    Synchronization of molecular reactions in a macroscopic volume may cause the volume's physical properties to change dynamically and thus reveal much about the reactions. As an example, experimental time series for so-called microtubule oscillations are analyzed in terms of a minimal model...... for this complex polymerization-depolymerization cycle. The model reproduces well the qualitatively different time series that result from different experimental conditions, and illuminates the role and importance of individual processes in the cycle. Simple experiments are suggested that can further test...... and define the model and the polymer's reaction cycle....

  19. Microtubules as mechanical force sensors.

    Science.gov (United States)

    Karafyllidis, Ioannis G; Lagoudas, Dimitris C

    2007-03-01

    Microtubules are polymers of tubulin subunits (dimers) arranged on a hexagonal lattice. Each tubulin dimer comprises two monomers, the alpha-tubulin and beta-tubulin, and can be found in two states. In the first state a mobile negative charge is located into the alpha-tubulin monomer and in the second into the beta-tubulin monomer. Each tubulin dimer is modeled as an electrical dipole coupled to its neighbors by electrostatic forces. The location of the mobile charge in each dimer depends on the location of the charges in the dimer's neighborhood. Mechanical forces that act on the microtubule affect the distances between the dimers and alter the electrostatic potential. Changes in this potential affect the mobile negative charge location in each dimer and the charge distribution in the microtubule. The net effect is that mechanical forces affect the charge distribution in microtubules. We propose to exploit this effect and use microtubules as mechanical force sensors. We model each dimer as a two-state quantum system and, following the quantum computation paradigm, we use discrete quantum random walk on the hexagonal microtubule lattice to determine the charge distribution. Different forces applied on the microtubule are modeled as different coin biases leading to different probability distributions of the quantum walker location, which are directly connected to different charge distributions. Simulation results show that there is a strong indication that microtubules can be used as mechanical force sensors and that they can also detect the force directions and magnitudes.

  20. Capture of microtubule plus-ends at the actin cortex promotes axophilic neuronal migration by enhancing microtubule tension in the leading process.

    Science.gov (United States)

    Hutchins, B Ian; Wray, Susan

    2014-01-01

    Microtubules are a critical part of neuronal polarity and leading process extension, thus microtubule movement plays an important role in neuronal migration. However, the dynamics of microtubules during the forward movement of the nucleus into the leading process (nucleokinesis) is unclear and may be dependent on the cell type and mode of migration used. In particular, little is known about cytoskeletal changes during axophilic migration, commonly used in anteroposterior neuronal migration. We recently showed that leading process actin flow in migrating GnRH neurons is controlled by a signaling cascade involving IP3 receptors, CaMKK, AMPK, and RhoA. In the present study, microtubule dynamics were examined in GnRH neurons. Failure of the migration of these cells leads to the neuroendocrine disorder Kallmann Syndrome. Microtubules translocated forward along the leading process shaft during migration, but reversed direction and moved toward the nucleus when migration stalled. Blocking calcium release through IP3 receptors halted migration and induced the same reversal of microtubule translocation, while blocking cortical actin flow prevented microtubules from translocating toward the distal leading process. Super-resolution imaging revealed that microtubule plus-end tips are captured at the actin cortex through calcium-dependent mechanisms. This work shows that cortical actin flow draws the microtubule network forward through calcium-dependent capture in order to promote nucleokinesis, revealing a novel mechanism engaged by migrating neurons to facilitate movement.

  1. The Pierrelatte's military factories dismantling

    International Nuclear Information System (INIS)

    Bourrelier, P.; Kassel, Ch.

    1999-01-01

    The site of Pierrelatte in France, receives since 1958 gaseous diffusion plants assigned to the uranium enrichment for military uses. Since 1996 Cogema implements, by order of the Cea, a dismantling operation of the site. The operation which will begin in 2000, is going to last ten years. This project shows difficulties that make it innovative. Its originality, the planning, the risks, the program progressing and the regulation aspects are detailed in this paper. Beyond the complicated technical operations, the wastes management is of primary importance for the good development of the operations. (A.L.B.)

  2. A structural model for microtubule minus-end recognition and protection by CAMSAP proteins

    NARCIS (Netherlands)

    Atherton, Joseph; Jiang, Kai; Stangier, Marcel M.; Luo, Yanzhang; Hua, Shasha; Houben, Klaartje; Van Hooff, Jolien J.E.; Joseph, Agnel Praveen; Scarabelli, Guido; Grant, Barry J.; Roberts, Anthony J.; Topf, Maya; Steinmetz, Michel O.; Baldus, Marc; Moores, Carolyn A.; Akhmanova, Anna

    2017-01-01

    CAMSAP and Patronin family members regulate microtubule minus-end stability and localization and thus organize noncentrosomal microtubule networks, which are essential for cell division, polarization and differentiation. Here, we found that the CAMSAP C-terminal CKK domain is widely present among

  3. Experience in the decontamination and dismantling of alpha facilities

    International Nuclear Information System (INIS)

    Charamathieu, A.

    1988-01-01

    Experience in dismantling alpha-containing radiochemical installations in France is described. The dismantling programme undertaken by the Societe des Techniques en Milieu Ionisant since 1977 is tabulated. This includes the dismantling of CALCIO and FLUO (plutonium metal), the dismantling of a slag processing plant, the dismantling of part of a medium activity plutonium mine and the dismantling of rooms 82-100 at Marcoule, France. (author)

  4. EL-3 dismantling of an experimental reactor

    International Nuclear Information System (INIS)

    1989-01-01

    The EL3 experimental reactor has been definitively stopped in march 1979. Its decommissioning has been pronounced in the end of 1982. This article is consecrated at decontamination and dismantling works necessited by its passage at the dismantling level 2 [fr

  5. Decontamination and dismantling at the CEA

    International Nuclear Information System (INIS)

    2006-01-01

    This document presents the dismantling policy at the CEA (French Research Center on the atomic energy), the financing of the decontamination and the dismantling, the regulatory framework, the knowledge and the technology developed at the CEA, the radiation protection, the environment monitoring and the installations. (A.L.B.)

  6. Polyamine sharing between tubulin dimers favours microtubule nucleation and elongation via facilitated diffusion.

    Directory of Open Access Journals (Sweden)

    Alain Mechulam

    2009-01-01

    Full Text Available We suggest for the first time that the action of multivalent cations on microtubule dynamics can result from facilitated diffusion of GTP-tubulin to the microtubule ends. Facilitated diffusion can promote microtubule assembly, because, upon encountering a growing nucleus or the microtubule wall, random GTP-tubulin sliding on their surfaces will increase the probability of association to the target sites (nucleation sites or MT ends. This is an original explanation for understanding the apparent discrepancy between the high rate of microtubule elongation and the low rate of tubulin association at the microtubule ends in the viscous cytoplasm. The mechanism of facilitated diffusion requires an attraction force between two tubulins, which can result from the sharing of multivalent counterions. Natural polyamines (putrescine, spermidine, and spermine are present in all living cells and are potent agents to trigger tubulin self-attraction. By using an analytical model, we analyze the implication of facilitated diffusion mediated by polyamines on nucleation and elongation of microtubules. In vitro experiments using pure tubulin indicate that the promotion of microtubule assembly by polyamines is typical of facilitated diffusion. The results presented here show that polyamines can be of particular importance for the regulation of the microtubule network in vivo and provide the basis for further investigations into the effects of facilitated diffusion on cytoskeleton dynamics.

  7. Laser dismantling of a glovebox

    International Nuclear Information System (INIS)

    Johnson, R.; Fender, M.

    1985-01-01

    A 5 kW laser has been used to cut up a 2.6 x 1 x 1 m glove box made of 5 mm mild steel with 12.5 mm perspex windows and 3 mm neoprene gaskets. The laser cut all components including the sandwich of perspex, neoprene and steel with ease. The production of fibrous filaments of perspex during the cutting process has been almost avoided by modifying the cutting variables. The combustion of material beyond that being cut has also been prevented by adopting the correct level of laser power. The problems encountered with loss of glove box rigidity with progressive dismantling are discussed, together with the relevance these problems have to possible cutting methods other than lasers. (author)

  8. Oscillatory fluid flow influences primary cilia and microtubule mechanics.

    Science.gov (United States)

    Espinha, Lina C; Hoey, David A; Fernandes, Paulo R; Rodrigues, Hélder C; Jacobs, Christopher R

    2014-07-01

    Many tissues are sensitive to mechanical stimuli; however, the mechanotransduction mechanism used by cells remains unknown in many cases. The primary cilium is a solitary, immotile microtubule-based extension present on nearly every mammalian cell which extends from the basal body. The cilium is a mechanosensitive organelle and has been shown to transduce fluid flow-induced shear stress in tissues, such as the kidney and bone. The majority of microtubules assemble from the mother centriole (basal body), contributing significantly to the anchoring of the primary cilium. Several studies have attempted to quantify the number of microtubules emanating from the basal body and the results vary depending on the cell type. It has also been shown that cellular response to shear stress depends on microtubular integrity. This study hypothesizes that changing the microtubule attachment of primary cilia in response to a mechanical stimulus could change primary cilia mechanics and, possibly, mechanosensitivity. Oscillatory fluid flow was applied to two different cell types and the microtubule attachment to the ciliary base was quantified. For the first time, an increase in microtubules around primary cilia both with time and shear rate in response to oscillatory fluid flow stimulation was demonstrated. Moreover, it is presented that the primary cilium is required for this loading-induced cellular response. This study has demonstrated a new role for the cilium in regulating alterations in the cytoplasmic microtubule network in response to mechanical stimulation, and therefore provides a new insight into how cilia may regulate its mechanics and thus the cells mechanosensitivity. Copyright © 2014 Wiley Periodicals, Inc.

  9. Feeding cells induced by phytoparasitic nematodes require γ-tubulin ring complex for microtubule reorganization.

    Directory of Open Access Journals (Sweden)

    Mohamed Youssef Banora

    2011-12-01

    Full Text Available Reorganization of the microtubule network is important for the fast isodiametric expansion of giant-feeding cells induced by root-knot nematodes. The efficiency of microtubule reorganization depends on the nucleation of new microtubules, their elongation rate and activity of microtubule severing factors. New microtubules in plants are nucleated by cytoplasmic or microtubule-bound γ-tubulin ring complexes. Here we investigate the requirement of γ-tubulin complexes for giant feeding cells development using the interaction between Arabidopsis and Meloidogyne spp. as a model system. Immunocytochemical analyses demonstrate that γ-tubulin localizes to both cortical cytoplasm and mitotic microtubule arrays of the giant cells where it can associate with microtubules. The transcripts of two Arabidopsis γ-tubulin (TUBG1 and TUBG2 and two γ-tubulin complex proteins genes (GCP3 and GCP4 are upregulated in galls. Electron microscopy demonstrates association of GCP3 and γ-tubulin as part of a complex in the cytoplasm of giant cells. Knockout of either or both γ-tubulin genes results in the gene dose-dependent alteration of the morphology of feeding site and failure of nematode life cycle completion. We conclude that the γ-tubulin complex is essential for the control of microtubular network remodelling in the course of initiation and development of giant-feeding cells, and for the successful reproduction of nematodes in their plant hosts.

  10. Centriolar CPAP/SAS-4 Imparts Slow Processive Microtubule Growth

    NARCIS (Netherlands)

    Sharma, Ashwani; Aher, Amol; Dynes, Nicola J; Frey, Daniel; Katrukha, Eugene A; Jaussi, Rolf; Grigoriev, Ilya; Croisier, Marie; Kammerer, Richard A; Akhmanova, Anna; Gönczy, Pierre; Steinmetz, Michel O

    2016-01-01

    Centrioles are fundamental and evolutionarily conserved microtubule-based organelles whose assembly is characterized by microtubule growth rates that are orders of magnitude slower than those of cytoplasmic microtubules. Several centriolar proteins can interact with tubulin or microtubules, but how

  11. The Japan Power Demonstration Reactor (JPDR) dismantling activities. Management of JPDR dismantling waste

    International Nuclear Information System (INIS)

    Abe, Masayoshi; Nakata, Susumu; Ito, Shinichi

    1996-01-01

    The management of wastes, both radioactive and non-radioactive, is one of the most important issues for a safe and reasonable dismantling operation of nuclear power plants. A large amount of radioactive wastes is arising from a reactor dismantling operation in a relatively short period time, ranging in a wide variety from very low level to relatively high level. Moreover non-radioactive waste is also in a huge amount. The dismantling operation of Japan Power Demonstration Reactor (JPDR) resulted in 24,440 tons of dismantling wastes, of which about 15% was radioactive and 85% non-radioactive. These wastes were managed successfully implementing a well developed management plan for JPDR dismantling waste. Research and development works for handling of JPDR dismantling wastes were performed, including fixation of loose contamination on surface, volume reduction and waste containers for on-site transportation and interim storage. The JPDR dismantling wastes generated were classified and categorized depending on their materials, characteristics and activity level. Approximately 2,100 tons of radioactive wastes were stored in the interim storage facilities on site using developed containers, and 1,670 tons of radioactive concrete waste were used for a safe demonstration test of a simple near-surface disposal for very low level waste. Other dismantling wastes such as steel and concrete which were categorized as non-radioactive were recycled and reused as useful resources. This paper describes the management of the JPDR dismantling wastes. (author)

  12. Consideration of dismantling operations in the design

    International Nuclear Information System (INIS)

    Dubourg; Bonin.

    1984-12-01

    This analysis shows that the parameters and the constraints taken into account at the design level to facilitate the exploitation and the maintenance make the dismantling and its preparation easier [fr

  13. Dismantling institutional racism: theory and action.

    Science.gov (United States)

    Griffith, Derek M; Mason, Mondi; Yonas, Michael; Eng, Eugenia; Jeffries, Vanessa; Plihcik, Suzanne; Parks, Barton

    2007-06-01

    Despite a strong commitment to promoting social change and liberation, there are few community psychology models for creating systems change to address oppression. Given how embedded racism is in institutions such as healthcare, a significant shift in the system's policies, practices, and procedures is required to address institutional racism and create organizational and institutional change. This paper describes a systemic intervention to address racial inequities in healthcare quality called dismantling racism. The dismantling racism approach assumes healthcare disparities are the result of the intersection of a complex system (healthcare) and a complex problem (racism). Thus, dismantling racism is a systemic and systematic intervention designed to illuminate where and how to intervene in a given healthcare system to address proximal and distal factors associated with healthcare disparities. This paper describes the theory behind dismantling racism, the elements of the intervention strategy, and the strengths and limitations of this systems change approach.

  14. Weapons dismantlement issues in independent Ukraine

    International Nuclear Information System (INIS)

    Zack, N.R.

    1995-01-01

    The American Association for the Advancement of Science sponsored a seminar during September 1993 in Kiev, Ukraine, titled, ''Toward a Nuclear-Free Future--Barriers and Problems.'' It brought together Ukrainians, Belarusians and Americans to discuss the legal, political, economic, technical, and safeguards and security dimensions of nuclear weapons dismantlement and destruction. US representatives initiated discussions on legal and treaty requirements and constraints, safeguards and security issues surrounding dismantlement, storage and disposition of nuclear materials, warhead transportation, and economic considerations. Ukrainians gave presentations on arguments for and against the Ukraine keeping nuclear weapons, the Ukrainian Parliament's nonapproval of START 1, alternative strategies for dismantling silos and launchers, and economic and security implications of nuclear weapons removal from the Ukraine. Participants from Belarus discussed proliferation and control regime issues. This paper will highlight and detail the issues, concerns and possible impacts of the Ukraine's dismantlement of its nuclear weapons

  15. General Research and Development problems in dismantling

    International Nuclear Information System (INIS)

    Lorin, C.

    1993-01-01

    R and D studies for dismantling nuclear facilities have been conducted in several domains: safety evaluation (3D cameras, gamma camera, gamma low level control bench, alpha measures); general studies (such as the Baladin software, an expert system for dismantling); decontamination techniques (utilisation of acid or base liquids, laser, ...); cutting techniques and tools (remote controlled grinder, remote controlled robot, carrier crane); robotics for remote operations and handling; waste processing

  16. The installation and dismantling of electrolytic cells

    International Nuclear Information System (INIS)

    Galushkin, N.V.

    1995-01-01

    This chapter of monograph is devoted to construction of aluminium electrolytic cells, their installation and dismantling. Therefore, the general characteristic and classification of aluminium electrolytic cells was considered. The anode and cathode structure was studied. The lining of cathode casing, the process of collection of anode gases, electrolytic cell cover, and electrical insulation was studied as well. The installation and dismantling of aluminium electrolytic cells was described.

  17. The dismantling of CEA nuclear installations

    International Nuclear Information System (INIS)

    Piketty, Laurence

    2016-03-01

    After having indicated locations of French nuclear installations which are currently being dismantled (about 30 installations), and recalled the different categories of radioactive wastes with respect to their activity level and the associated storage options, this article gives an overview of various aspects of dismantling, more precisely in the case of installations owned and managed by the CEA. These operations comprise the dismantling itself, the recovery and packaging of wastes, old effluents and spent fuels. The organisation and responsible departments within the CEA are presented, and the author outlines some operational problematic issues met due to the age of installations (traceability of activities, regulation evolutions). The issue of financing is then discussed, and its uncertainties are outlined. The dismantling strategy within the CEA-DEN is described, with reference to legal and regulatory frameworks. The next parts of the article address the organisation and the economic impact of these decontamination and dismantling activities within the CEA-DEN, highlight how R and D and advanced technology are a support to this activities as R and D actions address all scientific and technical fields of nuclear decontamination and dismantling. An overview of three important dismantling works is proposed: Fontenay-aux-Roses, the Marcoule CEA centre (a reference centre in the field of nuclear dismantling and decontamination) and the Grenoble CEA centre (reconversion in R and D activities in the fields of technologies of information, of communication, technologies, for health, and in renewable energies). The last part addresses the participation to the Strategic Committee of the Nuclear Sector (CSFN)

  18. RPF101, a new capsaicin-like analogue, disrupts the microtubule network accompanied by arrest in the G2/M phase, inducing apoptosis and mitotic catastrophe in the MCF-7 breast cancer cells

    International Nuclear Information System (INIS)

    Sá-Júnior, Paulo Luiz de; Pasqualoto, Kerly Fernanda Mesquita; Ferreira, Adilson Kleber; Tavares, Maurício Temotheo; Damião, Mariana Celestina Frojuello Costa Bernstorff; Azevedo, Ricardo Alexandre de; Câmara, Diana Aparecida Dias; Pereira, Alexandre; Madeiro de Souza, Dener; Parise Filho, Roberto

    2013-01-01

    Breast cancer is the world's leading cause of death among women. This situation imposes an urgent development of more selective and less toxic agents. The use of natural molecular fingerprints as sources for new bioactive chemical entities has proven to be a quite promising and efficient method. Capsaicin, which is the primary pungent compound in red peppers, was reported to selectively inhibit the growth of a variety tumor cell lines. Here, we report for the first time a novel synthetic capsaicin-like analogue, RPF101, which presents a high antitumor activity on MCF-7 cell line, inducing arrest of the cell cycle at the G2/M phase through a disruption of the microtubule network. Furthermore, it causes cellular morphologic changes characteristic of apoptosis and a decrease of Δψm. Molecular modeling studies corroborated the biological findings and suggested that RPF101, besides being a more reactive molecule towards its target, may also present a better pharmacokinetic profile than capsaicin. All these findings support the fact that RPF101 is a promising anticancer agent. -- Highlights: ► We report for the first time that RPF101 possesses anticancer properties. ► RPF101 induces apoptosis of human breast cancer cells. ► RPF 101 decreases mitochondrial potential and induces DNA fragmentation.

  19. Capu and Spire Assemble a Cytoplasmic Actin~Mesh that Maintains Microtubule Organization in the Drosophila Oocyte

    DEFF Research Database (Denmark)

    Dahlgaard, K.; Raposo, A.A.S.F.; Niccoli, T.

    2007-01-01

    Mutants in the actin nucleators Cappuccino and Spire disrupt the polarized microtubule network in the Drosophila oocyte that defines the anterior-posterior axis, suggesting that microtubule organization depends on actin. Here, we show that Cappuccino and Spire organize an isotropic mesh of actin...

  20. Manipulation and quantification of microtubule lattice integrity

    Directory of Open Access Journals (Sweden)

    Taylor A. Reid

    2017-08-01

    Full Text Available Microtubules are structural polymers that participate in a wide range of cellular functions. The addition and loss of tubulin subunits allows the microtubule to grow and shorten, as well as to develop and repair defects and gaps in its cylindrical lattice. These lattice defects act to modulate the interactions of microtubules with molecular motors and other microtubule-associated proteins. Therefore, tools to control and measure microtubule lattice structure will be invaluable for developing a quantitative understanding of how the structural state of the microtubule lattice may regulate its interactions with other proteins. In this work, we manipulated the lattice integrity of in vitro microtubules to create pools of microtubules with common nucleotide states, but with variations in structural states. We then developed a series of novel semi-automated analysis tools for both fluorescence and electron microscopy experiments to quantify the type and severity of alterations in microtubule lattice integrity. These techniques will enable new investigations that explore the role of microtubule lattice structure in interactions with microtubule-associated proteins.

  1. Study on treatment of dust by dismantling

    International Nuclear Information System (INIS)

    Torikai, K.; Suzuki, K.

    1987-01-01

    In dismantling of nuclear reactors, various kinds of treatment of dust generated by cutting or dismantling concrete structures of components of reactors are evaluated for safety, cost, and performance comparing the work in air with water. A method of dust treatment for work in air is discussed. The dry method has an easy operation in practice and a good performance in the equipment, but has problem on the prevention from radioactive contamination by diffusion of dust in air. For the purpose of advancing the strong points and eliminating the weak points in dry method, an improved venturi scrubber system is proposed for dismantling work as a dust collecting system. The system consists of dust absorbing pipe, dust collector, separator of dust and water and dust transfer equipment to a storage of waste. This system would be expected to have better performance and lower operating cost in decommissioning nuclear reactors, especially, the number of dust filters, for example, HEPA filters, will be considerably saved

  2. Vandellos-I Dismantling nearing completion

    International Nuclear Information System (INIS)

    Armada, J. R.

    2004-01-01

    Spain is witnessing the phase-out of a nuclear power plant. It is a unique experience in our country and therefore the dismantling work has been watched closely, not only from here but also from abroad. The Empresa Nacional de Residuos Radiactivos (ENRESA) is in charge of managring the dismantling and decommissioning work of the Vandellos-1 nuclear power plant, located in the municipally of l' Hospitalet de l'Infant (Tarragona). The work began five years ago and has been executed on schedule. The appearance of what was one of the first Spanish commercial nuclear power plants has been changed radically to leave premises suitable for any other activity. (Author)

  3. Economical dismantling of nuclear power stations

    International Nuclear Information System (INIS)

    Mallok, J.; Andermann, H.

    1999-01-01

    The dismantling of nuclear power stations requires a high degree of security and economic efficiency due to the strong contamination of components and the close spatial conditions. In order to protect involved staff from radiation, modern remote-controlled technology is applied in sectors with heavy radioactive contamination such as reactor pressure vessels. The article shows, that the dismantling of reactor pressure vessels using a remote-controlled milling machine developed by the Siemens subsidiary Mechanik Center Erlangen GmbH, can be done in a secure and efficient way. (orig.) [de

  4. Temperature buffer test. Dismantling operation

    Energy Technology Data Exchange (ETDEWEB)

    Aakesson, Mattias [Clay Technology AB, Lund (Sweden)

    2010-12-15

    The Temperature Buffer Test (TBT) is a joint project between SKB/ANDRA and supported by ENRESA (modelling) and DBE (instrumentation), which aims at improving the understanding and to model the thermo-hydro-mechanical behavior of buffers made of swelling clay submitted to high temperatures (over 100 deg C) during the water saturation process. The test has been carried out in a KBS-3 deposition hole at Aespoe HRL. It was installed during the spring of 2003. Two heaters (3 m long, 0.6 m diameter) and two buffer arrangements have been investigated: the lower heater was surrounded by bentonite in the usual way, whereas the upper heater was surrounded by a ring of sand. The test was dismantled and sampled during a period from the end of October 2009 to the end of April 2010, and this report describes this operation. Different types of samples have been obtained during this operation. A large number of diameter 50 mm bentonite cores have been taken for analysis of water content and density. Large pieces, so-called big sectors, have been taken for hydro-mechanical and chemical characterizations. Finally, there has been an interest to obtain different types of interface samples in which bentonite were in contact with sand, iron or concrete. One goal has been to investigate the retrievability of the upper heater, given the possibility to remove the surrounding sand shield, and a retrieval test has therefore been performed. The sand in the shield was first removed with an industrial vacuum cleaner after loosening the material through mechanical means (with hammer drill and core machine). A front loader was subsequently used for applying a sufficient lifting force to release the heater from the bentonite underneath. The experiment has been documented in different aspects: measurements of the coordinate (height or radius) of different interfaces (between bentonite blocks and between bentonite and sand); verification of sensor positions and retrieval of sensors for subsequent

  5. Temperature buffer test. Dismantling operation

    International Nuclear Information System (INIS)

    Aakesson, Mattias

    2010-12-01

    The Temperature Buffer Test (TBT) is a joint project between SKB/ANDRA and supported by ENRESA (modelling) and DBE (instrumentation), which aims at improving the understanding and to model the thermo-hydro-mechanical behavior of buffers made of swelling clay submitted to high temperatures (over 100 deg C) during the water saturation process. The test has been carried out in a KBS-3 deposition hole at Aespoe HRL. It was installed during the spring of 2003. Two heaters (3 m long, 0.6 m diameter) and two buffer arrangements have been investigated: the lower heater was surrounded by bentonite in the usual way, whereas the upper heater was surrounded by a ring of sand. The test was dismantled and sampled during a period from the end of October 2009 to the end of April 2010, and this report describes this operation. Different types of samples have been obtained during this operation. A large number of diameter 50 mm bentonite cores have been taken for analysis of water content and density. Large pieces, so-called big sectors, have been taken for hydro-mechanical and chemical characterizations. Finally, there has been an interest to obtain different types of interface samples in which bentonite were in contact with sand, iron or concrete. One goal has been to investigate the retrievability of the upper heater, given the possibility to remove the surrounding sand shield, and a retrieval test has therefore been performed. The sand in the shield was first removed with an industrial vacuum cleaner after loosening the material through mechanical means (with hammer drill and core machine). A front loader was subsequently used for applying a sufficient lifting force to release the heater from the bentonite underneath. The experiment has been documented in different aspects: measurements of the coordinate (height or radius) of different interfaces (between bentonite blocks and between bentonite and sand); verification of sensor positions and retrieval of sensors for subsequent

  6. Microtubule heterogeneity of Ornithogalum umbellatum ovary epidermal cells: non-stable cortical microtubules and stable lipotubuloid microtubules.

    Science.gov (United States)

    Kwiatkowska, Maria; Stępiński, Dariusz; Polit, Justyna T; Popłońska, Katarzyna; Wojtczak, Agnieszka

    2011-01-01

    Lipotubuloids, structures containing lipid bodies and microtubules, are described in ovary epidermal cells of Ornithogalum umbellatum. Microtubules of lipotubuloids can be fixed in electron microscope fixative containing only buffered OsO(4) or in glutaraldehyde with OsO(4) post-fixation, or in a mixture of OsO(4) and glutaraldehyde. None of these substances fixes cortical microtubules of ovary epidermis of this plant which is characterized by dynamic longitudinal growth. However, cortical microtubules can be fixed with cold methanol according immunocytological methods with the use of β-tubulin antibodies and fluorescein. The existence of cortical microtubules has also been evidenced by EM observations solely after the use of taxol, microtubule stabilizer, and fixation in a glutaraldehyde/OsO(4) mixture. These microtubules mostly lie transversely, sometimes obliquely, and rarely parallel to the cell axis. Staining, using Ruthenium Red and silver hexamine, has revealed that lipotubuloid microtubules surface is covered with polysaccharides. The presumption has been made that the presence of a polysaccharide layer enhances the stability of lipotubuloid microtubules.

  7. The WAK decommissioning and dismantling program

    International Nuclear Information System (INIS)

    Eiben, K.; Fritz, P.

    1995-01-01

    After an extensive rinsing of the reprocessing equipment the operation in the plant was terminated in 1991 following the principal political decision to abolish reprocessing of nuclear fuel in Germany. Since July 1991 only the safety relevant units are still in operation including the waste storage facilities for 80 m 3 of high active waste concentrate (HAWC). The decommissioning and dismantling will be achieved in six steps taking into account that some of the reprocessing equipment can be dismantled before and the rest only after the HAWC has been vitrified approximately by mid 2000. So far two licenses for decommissioning have been granted. An application for the dismantling of twelve systems in the process building including headend and tailend facilities will be licensed in 1995. The remote dismantling of equipment from the hot cells in the process building is being planned and will be executed between 1998--2001. New remote handling equipment will be cold tested in a test facility scheduled to start in the middle of this year. The final task is the green meadow after demolishing of the building and remediation of the site which is scheduled for 2005

  8. Method and apparatus for dismantling mechanical anchors

    Energy Technology Data Exchange (ETDEWEB)

    Dubovskiy, Yu P; Chendev, F S; Gritsayuk, B I; Gubin, N I; Osipov, S P

    1982-01-01

    This apparatus is designed to reduce the amount of labor required to dismantle mechanical anchors while at the same time lowering expenditures for lumber. Longwall beams and timber skips are used to support the cap and any fractured rock faces. The apparatus itself has grooves, vertical guides, and a drive system to position the longwall beams.

  9. Method of dismantling nuclear fuel elements

    International Nuclear Information System (INIS)

    Adams, G.J.

    1983-01-01

    Nuclear fuel assemblies of the kind comprising fuel pins in dimpled cellular grids are freed from the grids to aid dismantling of the assemblies by causing a rotary sleeve to pass concentrically over the pins to remove the dimples in the grids and thereby increase the freedom of the pins in the cells of the grids. (author)

  10. Microtubule nucleation and organization in dendrites

    Science.gov (United States)

    Delandre, Caroline; Amikura, Reiko; Moore, Adrian W.

    2016-01-01

    ABSTRACT Dendrite branching is an essential process for building complex nervous systems. It determines the number, distribution and integration of inputs into a neuron, and is regulated to create the diverse dendrite arbor branching patterns characteristic of different neuron types. The microtubule cytoskeleton is critical to provide structure and exert force during dendrite branching. It also supports the functional requirements of dendrites, reflected by differential microtubule architectural organization between neuron types, illustrated here for sensory neurons. Both anterograde and retrograde microtubule polymerization occur within growing dendrites, and recent studies indicate that branching is enhanced by anterograde microtubule polymerization events in nascent branches. The polarities of microtubule polymerization events are regulated by the position and orientation of microtubule nucleation events in the dendrite arbor. Golgi outposts are a primary microtubule nucleation center in dendrites and share common nucleation machinery with the centrosome. In addition, pre-existing dendrite microtubules may act as nucleation sites. We discuss how balancing the activities of distinct nucleation machineries within the growing dendrite can alter microtubule polymerization polarity and dendrite branching, and how regulating this balance can generate neuron type-specific morphologies. PMID:27097122

  11. Assembly and control of large microtubule complexes

    Science.gov (United States)

    Korolev, Kirill; Ishihara, Keisuke; Mitchison, Timothy

    Motility, division, and other cellular processes require rapid assembly and disassembly of microtubule structures. We report a new mechanism for the formation of asters, radial microtubule complexes found in very large cells. The standard model of aster growth assumes elongation of a fixed number of microtubules originating from the centrosomes. However, aster morphology in this model does not scale with cell size, and we found evidence for microtubule nucleation away from centrosomes. By combining polymerization dynamics and auto-catalytic nucleation of microtubules, we developed a new biophysical model of aster growth. The model predicts an explosive transition from an aster with a steady-state radius to one that expands as a travelling wave. At the transition, microtubule density increases continuously, but aster growth rate discontinuously jumps to a nonzero value. We tested our model with biochemical perturbations in egg extract and confirmed main theoretical predictions including the jump in the growth rate. Our results show that asters can grow even though individual microtubules are short and unstable. The dynamic balance between microtubule collapse and nucleation could be a general framework for the assembly and control of large microtubule complexes. NIH GM39565; Simons Foundation 409704; Honjo International 486 Scholarship Foundation.

  12. Cleansing and dismantling of CEA-Saclay nuclear licensed facilities

    International Nuclear Information System (INIS)

    Jeanjacques, Michel; Delaire, Isabelle; Glevarec, Rebecca; Mandard, Lionel; Martin, Jean-Louis; Serrano, Roger

    2013-01-01

    This summary presents the cleansing and dismantling operations currently realized on the CEA center of Saclay (CEA-Saclay). It was initiated at the beginning of the 2000 years a cleansing and dismantling program of the old Nuclear Licensed Facilities (NLF). Currently this program relates the dismantling operations to the Hot Laboratories (Laboratoires de Haute Activite: LHA) and the old workshops of the Liquid Waste Treatment Plant (Station des Effluents Liquides: STEL), the dismantling preparation of Ulysse reactor and the dismantling studies to the Solid Waste Management Plant (SWMP; Zone de Gestion des Dechets Solides) and the Osiris reactor. (authors)

  13. Value estimation of end of life vehicles as a source of competitive advantage for dismantling station

    Directory of Open Access Journals (Sweden)

    Monika Kosacka

    2016-03-01

    Full Text Available   Background: End of Life vehicles become an emerging problem because of the type of waste which they are. Each country is creating own recycling network where ELVs are well secured and recycled. Poland is a country where the system is not working correct because of a high absorption of ELVs by illegal dismantling entities which are more competitive than legal elements of recycling network. The problem is well known but there is still lack of solution. The purpose of this article is to present the concept of tools for the valuation of ELVs in order to improve the competitiveness of disassembly stations. Methods: The research methodology consists of a literature review as well as observations, surveys, BPMN and UML diagrams. On the basis of literature review and observations the problem was identified. The surveys were elaborated in order to identify requirements for the concept of the tool. BPMN and UML diagrams were used to model the processes in dismantling station and the information flow between the user and the tool. Results: There was established a concept of the tool - ELV's Calculator which support decisions of ELV's value estimation. Conclusions: Improving competitiveness of legal dismantling station is extremely important issue in order to provide safe for Environment and People and economically justified ELVs' management. Legal entities have to follow the law what makes their business cost higher. This paper provides a solution of encouraging people to return ELVs to legal dismantlers by offering them price adequate to market demand.    

  14. In-situ dismantling of plutonium-contaminated glove box

    International Nuclear Information System (INIS)

    Numata, Koji; Watanabe, Hisashi; Ishikawa, Hisashi; Miyo, Hiroaki; Ohtsuka, Katsuyuki

    1980-01-01

    A plutonium-contaminated glove box was dismantled along with the development of the treatment techniques for plutonium-bearing wastes. The objectives of this in-situ dismantling of the glove box are to reuse the Plutonium Fuel Fabrication Facility more efficiently, to reduce the volume of wastes generated during the dismantling, and to acquire dismantling techniques for decommissioning the Plutonium Fuel Fabrication Facility in the future. Prior to the dismantling works, a greenhouse for decontamination was installed, and the decontamination with surfactants was performed. Unremovable contamination was coated with paint. After this greenhouse was removed, the main greenhouse for dismantling and three greenhouses for contamination control were assembled. The main workers wearing protective devices engaged in dismantling works in the greenhouse. As the protective devices, anorak type PVC suits with air line masks, Howell type pressurized suits, and respirators were used. The tools used for the dismantling are a plasma cutter, an electric nibbler, an electric disk grinder, an electric circular saw and an electric jig saw. The results of the dismantling in-situ were compared with two previous cases of dismantling carried out by different procedures. In the case of in-situ dismantling, the volume of wastes was 1.6 - 1.8 m 3 /m 3 of glove box, and considerable reduction was realized. (Kako, I.)

  15. Microtubule dynamics: Caps, catastrophes, and coupled hydrolysis

    DEFF Research Database (Denmark)

    Flyvbjerg, H.; Holy, T.E.; Leibler, S.

    1996-01-01

    An effective theory is formulated for the dynamics of the guanosine triphosphate (GTP) cap believed to stabilize growing microtubules. The theory provides a ''coarse-grained'' description of the cap's dynamics. ''Microscopic'' details, such as the microtubule lattice structure and the fate of its...

  16. Biological Information Processing in Single Microtubules

    Science.gov (United States)

    2014-03-05

    generated by synchronized oscillations of microtubules, centrosomes and chromosomes regulate the dynamics of mitosis and meiosis, Yue Zhao and Qimin...of frequency by a single microtubule. Green arrows depict the peaks that appear in absorption and disappear in transmission. Purple arrows show

  17. Mechanics of microtubules: effects of protofilament orientation.

    Science.gov (United States)

    Donhauser, Zachary J; Jobs, William B; Binka, Edem C

    2010-09-08

    Microtubules are hollow cylindrical polymers of the protein tubulin that play a number of important dynamic and structural roles in eukaryotic cells. Both in vivo and in vitro microtubules can exist in several possible configurations, differing in the number of protofilaments, helical rise of tubulin dimers, and protofilament skew angle with respect to the main tube axis. Here, finite element modeling is applied to examine the mechanical response of several known microtubule types when subjected to radial deformation. The data presented here provide an important insight into microtubule stiffness and reveal that protofilament orientation does not affect radial stiffness. Rather, stiffness is primarily dependent on the effective Young's modulus of the polymerized material and the effective radius of the microtubule. These results are also directly correlated to atomic force microscopy nanoindentation measurements to allow a more detailed interpretation of previous experiments. When combined with experimental data that show a significant difference between microtubules stabilized with a slowly hydrolyzable GTP analog and microtubules stabilized with paclitaxel, the finite element data suggest that paclitaxel increases the overall radial flexibility of the microtubule wall. Copyright 2010 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  18. Decommissioning and dismantling reactors and managing waste

    International Nuclear Information System (INIS)

    Bensoussan, E.; Reicher-Fournel, N.

    2005-01-01

    In the early forties/fifties, a number of countries launched the first developments in the field of nuclear power. Some of them now have large numbers of nuclear facilities and nuclear power plants which have met, and continue to meet, the objectives for which they were designed and built. Other plants, including nuclear fuel production and enrichment plants, experimental reactors or research reactors, will have to be dismantled and demolished in the near future. These activities are handled differently in different countries as a function of specific energy policies, advanced development plants, current financial resources, the availability of qualified engineers and specialized industries able to handle projects of this kind, as well as other factors. All dismantling and demolition projects serve the purpose of returning the respective sites to green-field conditions. (orig.)

  19. Advanced robotics for decontamination and dismantlement

    International Nuclear Information System (INIS)

    Hamel, W.R.; Haley, D.C.

    1994-01-01

    The decontamination and dismantlement (D ampersand D) robotics technology application area of the US Department of Energy's Robotics Technology Development Program is explained and described. D ampersand D robotic systems show real promise for the reduction of human exposure to hazards, for improvement of productivity, and for the reduction of secondary waste generation. Current research and development pertaining to automated floor characterization, robotic equipment removal, and special inspection is summarized. Future research directions for these and emerging activities is given

  20. SGDES: Management system dismantling of ENRESA

    International Nuclear Information System (INIS)

    Julian, A. de; Fernandez, M.; Vidaechea, S.

    2013-01-01

    ENRESA, the Spanish public company responsible for managing radioactive waste and nuclear facilities decommissioning, has developed a management information system (SGDES) for the decommissioning of nuclear power plants. Dismantling activities require a rigorous operations control within highly specialized, process systematization and safety framework, both under human and technological point of view. SGDES system is capable of responding to the mentioned operational needs, efficiently and safely.

  1. Nuclear safety training program (NSTP) for dismantling

    International Nuclear Information System (INIS)

    Cretskens, Pieter; Lenie, Koen; Mulier, Guido

    2014-01-01

    European Control Services (GDF Suez) has developed and is still developing specific training programs for the dismantling and decontamination of nuclear installations. The main topic in these programs is nuclear safety culture. We therefore do not focus on technical training but on developing the right human behavior to work in a 'safety culture' environment. The vision and techniques behind these programs have already been tested in different environments: for example the dismantling of the BN MOX Plant in Dessel (Belgium), Nuclear Safety Culture Training for Electrabel NPP Doel..., but also in the non-nuclear industry. The expertise to do so was found in combining the know-how of the Training and the Nuclear Department of ECS. In training, ECS is one of the main providers of education in risky tasks, like elevation and manipulation of charges, working in confined spaces... but it does also develop training on demand to improve safety in a certain topic. Radiation Protection is the core business in the Nuclear Department with a presence on most of the nuclear sites in Belgium. Combining these two domains in a nuclear safety training program, NSTP, is an important stage in a dismantling project due to specific contamination, technical and other risks. It increases the level of safety and leads to a harmonization of different working cultures. The modular training program makes it possible to evaluate constantly as well as in group or individually. (authors)

  2. LEP Dismantling Reaches Half-Way Stage

    CERN Multimedia

    2001-01-01

    LEP's last superconducting module leaves its home port... Just seven months into the operation, LEP dismantling is forging ahead. Two of the eight arcs which form the tunnel have already been emptied and the last of the accelerator's radiofrequency (RF) cavities has just been raised to the surface. The 160 people working on LEP dismantling have reason to feel pleased with their progress. All of the accelerator's 72 superconducting RF modules have already been brought to the surface, with the last one being extracted on 2nd May. This represents an important step in the dismantling process, as head of the project, John Poole, explains. 'This was the most delicate part of the project, because the modules are very big and they could only come out at one place', he says. The shaft at point 1.8 through which the RF cavity modules pass is 18 metres in diameter, while each module is 11.5 metres long. Some modules had to travel more than 10 kilometres to reach the shaft. ... is lifted up the PM 1.8 shaft, after a m...

  3. Remote tool development for nuclear dismantling operations

    International Nuclear Information System (INIS)

    Craig, G.; Ferlay, J.C.; Ieracitano, F.

    2003-01-01

    Remote tool systems to undertake nuclear dismantling operations require careful design and development not only to perform their given duty but to perform it safely within the constraints imposed by harsh environmental conditions. Framatome ANP NUCLEAR SERVICES has for a long time developed and qualified equipment to undertake specific maintenance operations of nuclear reactors. The tool development methodology from this activity has since been adapted to resolve some very challenging reactor dismantling operations which are demonstrated in this paper. Each nuclear decommissioning project is a unique case, technical characterisation data is generally incomplete. The development of the dismantling methodology and associated equipment is by and large an iterative process combining design and simulation with feasibility and validation testing. The first stage of the development process involves feasibility testing of industrial tools and examining adaptations necessary to control and deploy the tool remotely with respect to the chosen methodology and environmental constraints. This results in a prototype tool and deployment system to validate the basic process. The second stage involves detailed design which integrates any remaining technical and environmental constraints. At the end of this stage, tools and deployment systems, operators and operating procedures are qualified on full scale mock ups. (authors)

  4. Learning-induced and stathmin-dependent changes in microtubule stability are critical for memory and disrupted in ageing

    Science.gov (United States)

    Uchida, Shusaku; Martel, Guillaume; Pavlowsky, Alice; Takizawa, Shuichi; Hevi, Charles; Watanabe, Yoshifumi; Kandel, Eric R.; Alarcon, Juan Marcos; Shumyatsky, Gleb P.

    2014-01-01

    Changes in the stability of microtubules regulate many biological processes, but their role in memory remains unclear. Here we show that learning causes biphasic changes in the microtubule-associated network in the hippocampus. In the early phase, stathmin is dephosphorylated, enhancing its microtubule-destabilizing activity by promoting stathmin-tubulin binding, whereas in the late phase these processes are reversed leading to an increase in microtubule/KIF5-mediated localization of the GluA2 subunit of AMPA receptors at synaptic sites. A microtubule stabilizer paclitaxel decreases or increases memory when applied at the early or late phases, respectively. Stathmin mutations disrupt changes in microtubule stability, GluA2 localization, synaptic plasticity and memory. Aged wild-type mice show impairments in stathmin levels, changes in microtubule stability, and GluA2 localization. Blocking GluA2 endocytosis rescues memory deficits in stathmin mutant and aged wild-type mice. These findings demonstrate a role for microtubules in memory in young adult and aged individuals. PMID:25007915

  5. Microtubule networks for plant cell division

    NARCIS (Netherlands)

    Keijzer, de Jeroen; Mulder, B.M.; Janson, M.E.

    2014-01-01

    During cytokinesis the cytoplasm of a cell is divided to form two daughter cells. In animal cells, the existing plasma membrane is first constricted and then abscised to generate two individual plasma membranes. Plant cells on the other hand divide by forming an interior dividing wall, the so-called

  6. Microtubule bundling plays a role in ethylene-mediated cortical microtubule reorientation in etiolated Arabidopsis hypocotyls.

    Science.gov (United States)

    Ma, Qianqian; Sun, Jingbo; Mao, Tonglin

    2016-05-15

    The gaseous hormone ethylene is known to regulate plant growth under etiolated conditions (the 'triple response'). Although organization of cortical microtubules is essential for cell elongation, the underlying mechanisms that regulate microtubule organization by hormone signaling, including ethylene, are ambiguous. In the present study, we demonstrate that ethylene signaling participates in regulation of cortical microtubule reorientation. In particular, regulation of microtubule bundling is important for this process in etiolated hypocotyls. Time-lapse analysis indicated that selective stabilization of microtubule-bundling structures formed in various arrays is related to ethylene-mediated microtubule orientation. Bundling events and bundle growth lifetimes were significantly increased in oblique and longitudinal arrays, but decreased in transverse arrays in wild-type cells in response to ethylene. However, the effects of ethylene on microtubule bundling were partially suppressed in a microtubule-bundling protein WDL5 knockout mutant (wdl5-1). This study suggests that modulation of microtubule bundles that have formed in certain orientations plays a role in reorienting microtubule arrays in response to ethylene-mediated etiolated hypocotyl cell elongation. © 2016. Published by The Company of Biologists Ltd.

  7. Decontamination and partial dismantling of the Eurochemic plant. Part 1

    International Nuclear Information System (INIS)

    Detilleux, E.; Geens, L.; Hild, W.; Klonk, W.

    1980-09-01

    A description is given of the partial dismantling of the dissolver used for fuel elements of up to 1.6 wt % 235 U enrichment, and of the total dismantling of the dissolver for highly enriched fuel elements. The corresponding head-end cells have been decontaminated, allowing prolonged interventions, either in view of refurbishing or complete dismantling. An assessment of required manpower, dose commitments, material consumption, and waste production for all operations is given. (author)

  8. Achievements and prospects of robotics in dismantling operations

    International Nuclear Information System (INIS)

    Clement, G.; Goetghebeur, S.; Ravera, J.P.

    1993-01-01

    After a definition of 'robotic systems' (poly functionality is the main concept), the nuclear facilities that have used robotic systems for their dismantling are reviewed; the various robot intervention domains in dismantling, the different types of machines and the work carried out by robots are presented. Difficulties arising from robot utilization for reactor dismantling, robot design considerations, reliability, personnel training needs, tooling and costs are discussed. Applicability criteria are derived concerning radio protection, hard working conditions, task complexity, multiplicity and quality, and costs

  9. Remote dismantling of the French Brennilis nuclear power plant

    International Nuclear Information System (INIS)

    Studenski, Joerg

    2009-01-01

    The paper deals with the remote dismantling of the decommissioned EL4 prototype power plant Brennilis in France. The block contains the reactor pressure vessel including internals and biological shield, the piping and the control systems. The authors describe the general operation principle of the reactor to illustrate the peculiarities of the dismantling concept and the concept-related challenges. Detailed information is given concerning the following issues: creation of an access to the reactor block, the used remote technology, dismantling of the coolant piping and the axial shield, dismantling of the reactor pressure vessel and the lateral shield. Special attention is given on the minimization of the produced radioactive waste.

  10. Remote dismantling of the French Brennilis nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Studenski, Joerg [NUKEM Technologies GmbH (Germany)

    2009-07-01

    The paper deals with the remote dismantling of the decommissioned EL4 prototype power plant Brennilis in France. The block contains the reactor pressure vessel including internals and biological shield, the piping and the control systems. The authors describe the general operation principle of the reactor to illustrate the peculiarities of the dismantling concept and the concept-related challenges. Detailed information is given concerning the following issues: creation of an access to the reactor block, the used remote technology, dismantling of the coolant piping and the axial shield, dismantling of the reactor pressure vessel and the lateral shield. Special attention is given on the minimization of the produced radioactive waste.

  11. Clean-up and dismantling, Dismantling - legacy of the past, prospects for the future: CEA, a pioneer in the dismantling process, nuclear dismantling, research and innovation dedicated to dismantling

    International Nuclear Information System (INIS)

    Lorec, Amelie

    2016-01-01

    France - a world leader in the whole nuclear power cycle - is also responsible for the clean-up and dismantling of its end-of-life nuclear facilities. Here, the CEA is considered to be a pioneer both in the project ownership of work sites and in the R and D for optimising the timescales, costs and safety of those work sites. Its responsibilities range from defining the most appropriate scenario, characterising the radiological state of equipment and decontaminating premises, carrying out dismantling and optimising the resulting waste. With this wide range of skills and the diversity of its facilities, the CEA Nuclear Energy Division is developing innovative solutions which are already the subject of industrial transfers. Two-thirds of France's end-of-life nuclear facilities belong to the CEA - a situation connected with its history. This implies setting up clean-up and dismantling work sites which have unprecedented scientific, human and financial challenges. Every regulated nuclear installation (INB) (nuclear reactors, laboratories, etc.) has a limited operating life. When it stops being used, it is first cleaned up (removal of radioactive substances), then dismantled (disassembly of components) in accordance with the baseline safety requirements, and finally decommissioned so that it can be used for other purposes or be demolished. Cleanup and dismantling operations concern all the facility's components, such as hot (shielded) cells which can be found in some laboratories. As the owner of its clean-up and dismantling projects, the CEA also devotes a significant amount of R and D to reducing the timescales, costs and waste from current and future programmes, while improving their safety. The resulting innovations often lead to industrial transfers. (authors)

  12. Moonlighting microtubule-associated proteins: regulatory functions by day and pathological functions at night.

    Science.gov (United States)

    Oláh, J; Tőkési, N; Lehotzky, A; Orosz, F; Ovádi, J

    2013-11-01

    The sensing, integrating, and coordinating features of the eukaryotic cells are achieved by the complex ultrastructural arrays and multifarious functions of the cytoskeletal network. Cytoskeleton comprises fibrous protein networks of microtubules, actin, and intermediate filaments. These filamentous polymer structures are highly dynamic and undergo constant and rapid reorganization during cellular processes. The microtubular system plays a crucial role in the brain, as it is involved in an enormous number of cellular events including cell differentiation and pathological inclusion formation. These multifarious functions of microtubules can be achieved by their decoration with proteins/enzymes that exert specific effects on the dynamics and organization of the cytoskeleton and mediate distinct functions due to their moonlighting features. This mini-review focuses on two aspects of the microtubule cytoskeleton. On the one hand, we describe the heteroassociation of tubulin/microtubules with metabolic enzymes, which in addition to their catalytic activities stabilize microtubule structures via their cross-linking functions. On the other hand, we focus on the recently identified moonlighting tubulin polymerization promoting protein, TPPP/p25. TPPP/p25 is a microtubule-associated protein and it displays distinct physiological or pathological (aberrant) functions; thus it is a prototype of Neomorphic Moonlighting Proteins. The expression of TPPP/p25 is finely controlled in the human brain; this protein is indispensable for the development of projections of oligodendrocytes that are responsible for the ensheathment of axons. The nonphysiological, higher or lower TPPP/p25 level leads to distinct CNS diseases. Mechanisms contributing to the control of microtubule stability and dynamics by metabolic enzymes and TPPP/p25 will be discussed. Copyright © 2013 Wiley Periodicals, Inc.

  13. A novel mechanism important for the alignment of microtubules.

    Science.gov (United States)

    Wightman, Raymond; Turner, Simon R

    2008-04-01

    Using a live-cell imaging approach to study individual micro-tubules, we have compared microtubule behavior between net-like and aligned cortical arrays. In contrast to previous studies, a steep angled collision between the growing end of a microtubule and a preexisting microtubule was found to favor crossover. Frequencies of microtubule crossovers, bundling and catastrophes are similar regardless of whether the cell exhibited a net-like or aligned microtubule array. In the predominantly aligned array of petiole cells, severing occurs at the sites of microtubule crossovers and serves to remove unaligned microtubules and to increase microtubule density. Severing was observed to be rare in net-like arrays. Microtubule severing is carried out by the katanin enzyme. In this addendum, we present new insights into the possible mechanism of crossing over and preliminary data looking at organization of the array in a katanin mutant.

  14. Nuclear cleanup and decontamination for dismantling operations

    International Nuclear Information System (INIS)

    Bargues, S.; Solignac, Y.; Lapierre, Y.

    2003-01-01

    In the May 2003 issue of the review 'Controle', the French Nuclear Safety Authority (Autorite de Surete Nucleaire or ASN) reviewed the radiation protection and waste management principles applicable to dismantling operations carried out on nuclear installations, i.e. reactors, research laboratories, fuel cycle installations and nuclear power reactors. Estelle Chapelain, of the DGSNR (French General Directorate for Nuclear Safety and Radiation Protection), pointed out that dismantling work does not involve the same radioactive risks as operating an installation. For instance, 'the risk of disseminating radioactive material is generally greater because the dismantling process supposes the removal of one or more containment barriers'. In addition to this risk of internal exposure, the possibility of external irradiation of personnel must be taken into account due to the nature of the work carried out by the operators. The probability of conventional hazards is also accentuated, these hazards varying as work progresses (fire hazards during cutting operations, hazards associated with handling tasks, etc). Other risks must also be considered: hazards due to the ageing of installations, to loss of traceability, and finally the risks associated with waste management. Waste management falls within a strict regulatory framework specified by the decree dated December 31, 1999, which makes it compulsory to carry out a 'waste survey' with the aim of producing an inventory of waste and improving waste management. These surveys include 'waste zoning' to identify those areas liable to have been contaminated. These requirements lead operators to adapt their cleanup methodology in order to distinguish suspect rooms or equipment from those that can be deemed with certainty to be conventional. In its conclusion, the safety authority recalls the importance of 'the safety and radiation protection of dismantling operations being effectively managed and optimised, without imposing

  15. The dismantling of fast reactors: sodium processing

    International Nuclear Information System (INIS)

    Rodriguez, G.; Berte, M.; Serpante, J.P.

    1999-01-01

    Fast reactors require a coolant that does not slow down neutrons so water can not be used. Metallic sodium has been chosen because of its outstanding neutronic and thermal properties but sodium reacts easily with air and water and this implies that sodium-smeary components can not be considered as usual nuclear wastes. A stage of sodium neutralizing is necessary in the processing of wastes from fast reactors. Metallic sodium is turned into a chemically stable compound: soda, carbonates or sodium salts. This article presents several methods used by Framatome in an industrial way when dismantling sodium-cooled reactors. (A.C.)

  16. Capacitive tool standoff sensor for dismantlement tasks

    International Nuclear Information System (INIS)

    Schmitt, D.J.; Weber, T.M.; Liu, J.C.

    1996-01-01

    A capacitive sensing technology has been applied to develop a Standoff Sensor System for control of robotically deployed tools utilized in Decontamination and Dismantlement (D and D) activities. The system combines four individual sensor elements to provide non-contact, multiple degree-of-freedom control of tools at distances up to five inches from a surface. The Standoff Sensor has been successfully integrated to a metal cutting router and a pyrometer, and utilized for real-time control of each of these tools. Experiments demonstrate that the system can locate stationary surfaces with a repeatability of 0.034 millimeters

  17. Decommissioning and dismantling policy in Spain

    International Nuclear Information System (INIS)

    Landa, J.

    2004-01-01

    Decommissioning and dismantling nuclear installations is an increasingly important topic for governments, regulators, industries and civil society. There are many aspects that have to be carefully considered and planned, in many cases well in advance when they really need to be implemented. In my speech I am going to focus on policy-making considerations. Firstly I will go briefly over the current Spanish strategy on D and D, discussing the know-how we have gained from past experience. Then I will review the challenges that we will have to face in the near future, suggesting possible alternatives and approaches. I will finish talking a little bit about the international scene. (author)

  18. Lateral motion and bending of microtubules studied with a new single-filament tracking routine in living cells.

    Science.gov (United States)

    Pallavicini, Carla; Levi, Valeria; Wetzler, Diana E; Angiolini, Juan F; Benseñor, Lorena; Despósito, Marcelo A; Bruno, Luciana

    2014-06-17

    The cytoskeleton is involved in numerous cellular processes such as migration, division, and contraction and provides the tracks for transport driven by molecular motors. Therefore, it is very important to quantify the mechanical behavior of the cytoskeletal filaments to get a better insight into cell mechanics and organization. It has been demonstrated that relevant mechanical properties of microtubules can be extracted from the analysis of their motion and shape fluctuations. However, tracking individual filaments in living cells is extremely complex due, for example, to the high and heterogeneous background. We introduce a believed new tracking algorithm that allows recovering the coordinates of fluorescent microtubules with ∼9 nm precision in in vitro conditions. To illustrate potential applications of this algorithm, we studied the curvature distributions of fluorescent microtubules in living cells. By performing a Fourier analysis of the microtubule shapes, we found that the curvatures followed a thermal-like distribution as previously reported with an effective persistence length of ∼20 μm, a value significantly smaller than that measured in vitro. We also verified that the microtubule-associated protein XTP or the depolymerization of the actin network do not affect this value; however, the disruption of intermediate filaments decreased the persistence length. Also, we recovered trajectories of microtubule segments in actin or intermediate filament-depleted cells, and observed a significant increase of their motion with respect to untreated cells showing that these filaments contribute to the overall organization of the microtubule network. Moreover, the analysis of trajectories of microtubule segments in untreated cells showed that these filaments presented a slower but more directional motion in the cortex with respect to the perinuclear region, and suggests that the tracking routine would allow mapping the microtubule dynamical organization in cells

  19. Microtubule array reorientation in response to hormones does not involve changes in microtubule nucleation modes at the periclinal cell surface

    Science.gov (United States)

    Atkinson, Samantha; Kirik, Angela; Kirik, Viktor

    2014-01-01

    Aligned microtubule arrays spatially organize cell division, trafficking, and determine the direction of cell expansion in plant cells. In response to changes in environmental and developmental signals, cells reorganize their microtubule arrays into new configurations. Here, we tested the role of microtubule nucleation during hormone-induced microtubule array reorientation. We have found that in the process of microtubule array reorientation the ratios between branching, parallel, and de-novo nucleations remained constant, suggesting that the microtubule reorientation mechanism does not involve changes in nucleation modes. In the ton2/fass mutant, which has reduced microtubule branching nucleation frequency and decreased nucleation activity of the γ-tubulin complexes, microtubule arrays were able to reorient. Presented data suggest that reorientation of microtubules into transverse arrays in response to hormones does not involve changes in microtubule nucleation at the periclinal cell surface PMID:25135522

  20. The Dismantling of Nuclear Installations in France

    International Nuclear Information System (INIS)

    Bonnaure, P.

    2011-01-01

    As we saw in the previous article by Pierre Bonnaure, though it has long been decried for the dangers inherent in its production structures and the very long-lived waste that it generates, nuclear power may yet recover its credibility, particularly in France. However, on close examination, we see that the nuclear industry is beset by a number of unresolved questions, beginning with the dismantling of installations that have become obsolete or are set to become so. Nuclear power took off after the Second World War, but several generations of technology have been developed since then, and most currently functioning power-stations - mainly second-generation installations - are theoretically nearing the end of their useful lives, at least in terms of what was said when they were being built. The problem therefore arises of their dismantling and the clean-up of the sites on which they were built, a thorny question on which Pierre Bonnaure casts light in this article (prospects, strategies, financing, management of waste etc.). Unfortunately, it emerges that in France nothing has really been resolved, that public debate on the matter is decidedly limited and that investment (both financial investment and research) is not commensurate with the needs of a sector which is, after all, the source of three quarters of national electricity production. (author)

  1. Decontamination and dismantlement plan for international reviewing

    International Nuclear Information System (INIS)

    Wells, P.B.; Earle, O.K.; Klepikov, A.Kh.

    2000-01-01

    When developing a decommissioning plan, several factors need to be included. First and foremost is the issue of outline and scope. Specific to the BN-350, are issues related to short term tasks required to support the safe storage of the reactor for the next 50 years, and long term tasks required to dismantle the reactor, leaving some sort of final state, (brown field, green field, etc.) In addition, issues such as personnel and physical safety as well as environmental concerns must be addressed to ensure the shut down and dismantlement of the reactor is done in a safe manner, both for personnel and the environment. In addition to being the base document in which to support work, a D and D plan can also be utilized to obtain financial resources necessary to complete the plan, as is the case for the BN-350 Reactor located in Aktau, Kazakhstan. By providing a clear and complete D and D plan, which includes costs and schedules for each item, it is anticipated that donor countries will have the ability to review, approve, and provide financial support to complete the work described in the plan

  2. Dismantling without contaminating: The EUREX plant experience

    International Nuclear Information System (INIS)

    2001-01-01

    The EUREX pilot plant of ENEA Research Centre of Saluggia (Italy) reprocessed, between 1970 and 1983, some 600 elements and 1.5 tonnes of irradiated fuel from MTR and CANDU reactors. The general programme of denuclearization of the site actually focuses on the main priority of the conditioning of the about 400 m 3 of High and Low Level Liquid wastes stored in Saluggia. For this reason, in 1997 a project for the H and LLW conditioning, named 'CORA' has started. The 'CORA' unit will solidify the liquid wastes applying the Cold Crucible Melter (CCM) technology; due to the low volume amount of wastes to vitrify, the 'CORA' project has been accurately tailored in order to reduce social impact on public acceptance, costs and conditioning plant volumes to dismantle at the end of the work. For this reason, all the main nuclear components of the conditioning unit (input tank and pretreatment section, CC Melter, pot handling, off-gas system, interim glass storage) will be hosted inside four existing cells of the EUREX plant, duly dismantled. The EUREX plant services (electric and process fluid supplies, controlled areas, ventilation system...) will be reused too, revamped in some cases. The reuse of a nuclear plant which was built in the 60's, as the EUREX is, for future conditioning activities to be 'transplanted' there in the next years, it is not quite an easy job: the partial EUREX dismantling must permit an easy recovery of process areas and spread of contamination from old components (tanks, pipes, valves...) has to be minimized as far as possible. In order to minimize contamination spread, pipe cutting is made by a hydraulic shear, leaving the cut edges closed. Size reduction of pipes and tanks, to optimize the 5 m 3 steel storage containers filling is, as far as possible, made out of the working area of the cells. To achieve this goal a preliminary sketch of pipes to be cut and where the minimal cuts ought to be done is prepared before each intervention. The time

  3. Process cells dismantling of EUREX pant: previous activities

    International Nuclear Information System (INIS)

    Gili, M.

    1998-01-01

    In the '98-'99 period some process cells of the EUREX pant will be dismantled, in order to place there the liquid wastes conditioning plant 'CORA'. This report resumes the previous activities (plant rinsing campaigns and inactive Cell 014 dismantling), run in the past three years and the drawn experience [it

  4. The Japan Power Demonstration Reactor dismantling project. Radiation control

    International Nuclear Information System (INIS)

    Tomii, Hiroyuki; Seiki, Yoshihiro

    1996-01-01

    In the Japan Power Demonstration Reactor (JPDR) dismantling project, radiation control was performed properly with routine and special monitoring to keep the occupational safety and to collect data necessary for future dismantling of nuclear facilities. This report describes a summary of radiation control in the dismantling activities and some results of parametric analysis on dose equivalent evaluation, and introduces the following knowledge on radiological protection effectiveness of the dismantling systems applied in the project. a) Use of remote dismantling systems was effective in reducing equivalent workplace exposure. b) Utilization of existing facilities as radiation shield or radioactivity containment was effective in reducing workplace exposure, and also in increasing work efficiency. c) Use of underwater cutting systems was useful to minimize air contamination, and to reduce the dose equivalent rate in the working area. d) In the planning of dismantling, it is necessary to optimize the radiation protection by analyzing dismantling work procedures and evaluating radiological features of the dismantling systems applied, including additional work which the systems require brought from such activities. (author)

  5. Shielded Cells D ampersand D and Dismantlement System Requirements

    International Nuclear Information System (INIS)

    Witherspoon, R.L.

    1995-01-01

    This document describes the basis for the development of the System for Highly Radioactive Equipment Dismantlement or SHRED. It is the result of a thorough investigation into current and past dismantlement practices at shielded cell facilities around the DOE complex. This information has been used to formulate the development requirements for the SHRED

  6. Abrasive water jet cutting technique for biological shield concrete dismantlement

    International Nuclear Information System (INIS)

    Konno, T.; Narazaki, T.; Yokota, M.; Yoshida, H.; Miura, M.; Miyazaki, Y.

    1987-01-01

    The Japan Atomic Energy Research Institute (JAERI) is developing the abrasive-water jet cutting system to be applied to dismantling the biological shield walls of the JPDR as a part of the reactor dismantling technology development project. This is a total system for dismantling highly activated concrete. The concrete biological shield wall is cut into blocks by driving the abrasive-water jet nozzle, which is operated with a remote, automated control system. In this system, the concrete blocks are removed to a container, while the slurry and dust/mist which are generated during cutting are collected and treated, both automatically. It is a very practical method and will quite probably by used for actual dismantling of commercial power reactors in the future because it can minimize workers' exposure to radioactivity during dismantling, contributes to preventing diffusion of radiation, and reduces the volume of contaminated secondary waste

  7. STMI: several years of experience in nuclear plant dismantling

    International Nuclear Information System (INIS)

    Moreau, J.C.

    1985-01-01

    Since 1977, when STMI performed its first dismantling operation, the Company appreciably improved in that field through important operations: the dismantling of the calciothermy and fluoration metal Pu preparation facility, in La Hague reprocessing plant; the dismantling of the slag treatment chain, associated to calciothermy and fluoration processes, in La Hague reprocessing plant; and the cleaning of EL4 cell in Marcoule. To perform these operations, STMI's operating teams, on top of decontamination and dismantling technologies, strived to improve handling and transportation technologies, and to nuclearize many equipments. In order to increase its technical efficiency, STMI signed a cooperation agreement with FRAMATOME company. Therefore, the union between the operational know-hows of STMI and the design experience of TECHNICATOME allow the needs of any customs facing a dismantling case to be satisfied [fr

  8. Microtubules self-repair in response to mechanical stress

    Science.gov (United States)

    Schaedel, Laura; John, Karin; Gaillard, Jérémie; Nachury, Maxence V.; Blanchoin, Laurent; Théry, Manuel

    2015-11-01

    Microtubules--which define the shape of axons, cilia and flagella, and provide tracks for intracellular transport--can be highly bent by intracellular forces, and microtubule structure and stiffness are thought to be affected by physical constraints. Yet how microtubules tolerate the vast forces exerted on them remains unknown. Here, by using a microfluidic device, we show that microtubule stiffness decreases incrementally with each cycle of bending and release. Similar to other cases of material fatigue, the concentration of mechanical stresses on pre-existing defects in the microtubule lattice is responsible for the generation of more extensive damage, which further decreases microtubule stiffness. Strikingly, damaged microtubules were able to incorporate new tubulin dimers into their lattice and recover their initial stiffness. Our findings demonstrate that microtubules are ductile materials with self-healing properties, that their dynamics does not exclusively occur at their ends, and that their lattice plasticity enables the microtubules' adaptation to mechanical stresses.

  9. YB-1 promotes microtubule assembly in vitro through interaction with tubulin and microtubules

    Directory of Open Access Journals (Sweden)

    Baconnais Sonia

    2008-09-01

    Full Text Available Abstract Background YB-1 is a major regulator of gene expression in eukaryotic cells. In addition to its role in transcription, YB-1 plays a key role in translation and stabilization of mRNAs. Results We show here that YB-1 interacts with tubulin and microtubules and stimulates microtubule assembly in vitro. High resolution imaging via electron and atomic force microscopy revealed that microtubules assembled in the presence of YB-1 exhibited a normal single wall ultrastructure and indicated that YB-1 most probably coats the outer microtubule wall. Furthermore, we found that YB-1 also promotes the assembly of MAPs-tubulin and subtilisin-treated tubulin. Finally, we demonstrated that tubulin interferes with RNA:YB-1 complexes. Conclusion These results suggest that YB-1 may regulate microtubule assembly in vivo and that its interaction with tubulin may contribute to the control of mRNA translation.

  10. Dismantling the nuclear research reactor Thetis

    Energy Technology Data Exchange (ETDEWEB)

    Michiels, P. [Belgoprocess, 2480 Dessel (Belgium)

    2013-07-01

    The research reactor Thetis, in service since 1967 and stopped in 2003, is part of the laboratories of the institution of nuclear science of the University of Ghent. The reactor, of the pool-type, was used as a neutron-source for the production of radio-isotopes and for activation analyses. The reactor is situated in a water pool with inner diameter of 3 m. and a depth of 7.5 m. The reactor core is situated 5.3 m under water level. Besides the reactor, the pool contains pneumatic loops, handling tools, graphite blocks for neutron moderation and other experimental equipment. The building houses storage rooms for fissile material and sources, a pneumatic circuit for transportation of samples, primary and secondary cooling circuits, water cleaning resin circuits, a ventilation system and other necessary devices. Because of the experimental character of the reactor, laboratories with glove boxes and other tools were needed and are included in the dismantling program. The building is in 3 levels with a crawl-space. The ground-floor contains the ventilation installation, the purification circuits with tanks, cooling circuits and pneumatic transport system. On the first floor, around the reactor hall, the control-room, visiting area, end-station for pneumatic transport, waste-storage room, fuel storage room and the labs are located. The second floor contains a few laboratories and end stations of the two high speed transfer tubes. The lowest level of the pool is situated under ground level. The reactor has been operated at a power of 150 kW and had a max operating power of 250 kW. Belgoprocess has been selected to decommission the reactor, the labs, storage halls and associated circuits to free release the building for conventional reuse and for the removal of all its internals as legal defined. Besides the dose-rate risk and contamination risk, there is also an asbestos risk of contamination. During construction of the installation, asbestos-containing materials were

  11. Simulation for preparation of dismantling operations

    International Nuclear Information System (INIS)

    Carrere, J.M.; Idasiak, J.M.

    2003-01-01

    New applications of 3D models are still emerging. At first, simulation of dismantling operations has been used to illustrate the proposed scenarios, with 3D views or animated films, for: - internal and external communication; - technical reviews; - presentation to Safety Authorities. It helps a lot to explain the structure of the facility to dismantle, the proposed solutions, to convince people that the study is detailed enough. But 3D modelling is an investment in time and money. A lot of time is spent in collecting the drawings, and checking them with pictures, videos, interviews of operators, new measurements. This investment can be much more exploited, during all the life time of the decommissioning project, to avoid problems during operations, and so to save a lot of money. It is possible to have navigation or even immersion inside 3D models of facilities to dismantle, so that the project team or the operators can be familiar with the configuration of rooms, of accesses, with the location of equipment. A 3D model can hardly be as detailed as the real facility. Some simplifications have to be done, to avoid having too heavy models. But in a training process, 3D-models help to have rapidly an overview of complex environments. Dose uptake simulation is becoming also a tool for decommissioning projects. It is possible to compute either off line, or even in real time, the dose uptake of the operators, and to compare easily different options for the ALARA principle: decontamination or not, use of shielding or not. It requires to have not only the geometrical model, but also a radiological model of the facility, but with the use of gamma camera and spectrometry, it becomes easier. 3D-models can be used to integrate in an user-friendly way all the knowledge of a facility to decommission, and to update that knowledge during operations: reports on construction, on exploitation, on shut-down, physical and radiological measurements, traceability of wastes. Progress are

  12. Stabilization, not polymerization, of microtubules inhibits the nuclear translocation of STATs in adipocytes

    International Nuclear Information System (INIS)

    Gleason, Evanna L.; Hogan, Jessica C.; Stephens, Jacqueline M.

    2004-01-01

    Signal transducers and activators of transcriptions (STATs) are a family of latent transcription factors which are activated by a variety of growth factors and cytokines in many cell types. However, the mechanism by which these transcription factors translocate to the nucleus is poorly understood. The goal of this study was to determine the requirement of microfilaments and microtubules for cytokine induced STAT activation in cultured adipocytes. We used seven different actin-specific and microtubule-specific agents that are well-established effectors of these cytoskeletal networks. Our results clearly demonstrate that inhibition of microfilaments or the prevention of microtubule polymerization has no effect on the ability of STATs to be tyrosine phosphorylated or to translocate to the nucleus. However, we observed that paclitaxel, a microtubule stabilizer, resulted in a significant decrease in the nuclear translocation of STATs without affecting the cytosolic tyrosine phosphorylation of these transcription factors. In summary, our results demonstrate that the dynamic instability, but not the polymerization, of microtubules contributes to nuclear translocation of STAT proteins in adipocytes

  13. TIPsy tour guides: How microtubule plus-end tracking proteins (+TIPs facilitate axon guidance

    Directory of Open Access Journals (Sweden)

    Elizabeth A Bearce

    2015-06-01

    Full Text Available The growth cone is a dynamic cytoskeletal vehicle, which drives the end of a developing axon. It serves to interpret and navigate through the complex landscape and guidance cues of the early nervous system. The growth cone’s distinctive cytoskeletal organization offers a fascinating platform to study how extracellular cues can be translated into mechanical outgrowth and turning behaviors. While many studies of cell motility highlight the importance of actin networks in signaling, adhesion, and propulsion, both seminal and emerging works in the field have highlighted a unique and necessary role for microtubules in growth cone navigation. Here, we focus on the role of singular pioneer microtubules, which extend into the growth cone periphery and are regulated by a diverse family of microtubule plus-end tracking proteins (+TIPs. These +TIPs accumulate at the dynamic ends of microtubules, where they are well-positioned to encounter and respond to key signaling events downstream of guidance receptors, catalyzing immediate changes in microtubule stability and actin cross-talk, that facilitate both axonal outgrowth and turning events.

  14. Decommissioning and dismantling of nuclear installations

    International Nuclear Information System (INIS)

    Pelzer, N.

    1993-01-01

    The German law governing decommissioning and dismantling of nuclear installations can be called to be embryonic as compared to other areas of the nuclear regulatory system, and this is why the AIDN/INLA regional meeting organised by the German national committee in July 1992 in Schwerin has been intended to elaborate an assessment of the current legal situation and on this basis establish proposals for enhancement and development, taking into account the experience reported by experts from abroad. The proceedings comprise the paper of the opening session, 'Engineering and safety aspects of the decommissioning of nuclear installations', and the papers and discussions of the technical sessions entitled: - Comparative assessment of the regulatory regimes. - Legislation governing the decommissioning of nuclear installations in Germany. - Analysis of the purpose and law making substance of existing regulatory provisions for the decommissioning of nuclear installations. All seventeen papers of the meeting have been prepared for separate retrieval from the database. (orig./HSCH) [de

  15. Method of dismantling cylindrical structure by cutting

    International Nuclear Information System (INIS)

    Harada, Minoru; Mitsuo, Kohei; Yokota, Isoya; Nakamura, Kenjiro.

    1989-01-01

    This invention concerns a method of cutting and removing cylindrical structures, for example, iron-reinforced concrete materials such as thermal shielding walls in BWR type power plants into block-like form. That is, in a method of cutting and removing the cylindrical structure from the side of the outer wall, the structural material is cut from above to below successively in the axial direction and the circumferential direction by means abrasive jet by remote operation and cut into blocks each of a predetermined size. The cut out blocks are successively taken out. Cutting of the material from above to below by remote operation and taking out of small blocks causes no hazards to human body. Upon practicing the present invention, it is preferred to use a processing device for slurry and exhaust gases for preventing scattering of activated dismantled pieces or powdery dusts. (K.M.)

  16. Prefiltration of gaseous effluents in plant dismantling

    International Nuclear Information System (INIS)

    Pilot, G.; Pourprix, M.

    1991-01-01

    The dismantling techniques and mainly the thermal cutting tools can create large amounts of airbone dust, possibly contaminated in the case of the cutting of radioactive materials. Among the secondary solid emissions, the aerosols constitute the most mobile part which can disseminate contamination in the cell where the cutting operation takes place and in the ventilation ducts up to the HEPA filters. An optimised prefiltration coupled with a captation device at the aerosol generating source allows to avoid the dissemination of the contamination, to increase the life of HEPA filters and thus to reduce the amount of solid wastes. The object in this work was to select one or several cleaning devices, selection that can be done from the knowledge of the physico-chemical characteristics of the gas and aerosols to deal with, the available cleaning devices and the implied facility

  17. The Grenoble CEA Center: dismantled and rehabilitated

    International Nuclear Information System (INIS)

    Anon.

    2013-01-01

    The denuclearization program of the CEA center in Grenoble was launched in 2001. It involves 6 nuclear facilities (3 research reactors: Melusine, Siloette, and Siloe, and 1 laboratory (LAMA) and 2 units for processing wastes). The dismantling works were finished at the end of 2012 and the 2013 program concerns: the demolition of the buildings homing Melusine and Siloe reactors, the final rehabilitation of the Siloe raft, and the final rehabilitation of the laboratory and of the waste processing units. The budget is 117*10 6 euros for Siloe, 28*10 6 euros for Melusine, 6*10 6 euros for Siloette, 70*10 6 euros for the LAMA, and 90*10 6 euros for the 2 waste processing units. (A.C.)

  18. A Genome-wide RNAi Screen for Microtubule Bundle Formation and Lysosome Motility Regulation in Drosophila S2 Cells

    Directory of Open Access Journals (Sweden)

    Amber L. Jolly

    2016-01-01

    Full Text Available Long-distance intracellular transport of organelles, mRNA, and proteins (“cargo” occurs along the microtubule cytoskeleton by the action of kinesin and dynein motor proteins, but the vast network of factors involved in regulating intracellular cargo transport are still unknown. We capitalize on the Drosophila melanogaster S2 model cell system to monitor lysosome transport along microtubule bundles, which require enzymatically active kinesin-1 motor protein for their formation. We use an automated tracking program and a naive Bayesian classifier for the multivariate motility data to analyze 15,683 gene phenotypes and find 98 proteins involved in regulating lysosome motility along microtubules and 48 involved in the formation of microtubule filled processes in S2 cells. We identify innate immunity genes, ion channels, and signaling proteins having a role in lysosome motility regulation and find an unexpected relationship between the dynein motor, Rab7a, and lysosome motility regulation.

  19. Ferritin associates with marginal band microtubules

    International Nuclear Information System (INIS)

    Infante, Anthony A.; Infante, Dzintra; Chan, M.-C.; How, P.-C.; Kutschera, Waltraud; Linhartova, Irena; Muellner, Ernst W.; Wiche, Gerhard; Propst, Friedrich

    2007-01-01

    We characterized chicken erythrocyte and human platelet ferritin by biochemical studies and immunofluorescence. Erythrocyte ferritin was found to be a homopolymer of H-ferritin subunits, resistant to proteinase K digestion, heat stable, and contained iron. In mature chicken erythrocytes and human platelets, ferritin was localized at the marginal band, a ring-shaped peripheral microtubule bundle, and displayed properties of bona fide microtubule-associated proteins such as tau. Red blood cell ferritin association with the marginal band was confirmed by temperature-induced disassembly-reassembly of microtubules. During erythrocyte differentiation, ferritin co-localized with coalescing microtubules during marginal band formation. In addition, ferritin was found in the nuclei of mature erythrocytes, but was not detectable in those of bone marrow erythrocyte precursors. These results suggest that ferritin has a function in marginal band formation and possibly in protection of the marginal band from damaging effects of reactive oxygen species by sequestering iron in the mature erythrocyte. Moreover, our data suggest that ferritin and syncolin, a previously identified erythrocyte microtubule-associated protein, are identical. Nuclear ferritin might contribute to transcriptional silencing or, alternatively, constitute a ferritin reservoir

  20. Taxol crystals can masquerade as stabilized microtubules.

    Directory of Open Access Journals (Sweden)

    Margit Foss

    Full Text Available Taxol is a potent anti-mitotic drug used in chemotherapy, angioplastic stents, and cell biology research. By binding and stabilizing microtubules, Taxol inhibits their dynamics, crucial for cell division, motility, and survival. The drug has also been reported to induce formation of asters and bundles composed of stabilized microtubules. Surprisingly, at commonly used concentrations, Taxol forms crystals that rapidly bind fluorescent tubulin subunits, generating structures with an uncanny resemblance to microtubule asters and bundles. Kinetic and topological considerations suggest that tubulin subunits, rather than microtubules, bind the crystals. This sequestration of tubulin from the subunit pool would be expected to shift the equilibrium of free to polymerized tubulin to disfavor assembly. Our results imply that some previously reported Taxol-induced asters or bundles could include or be composed of tubulin-decorated Taxol crystals. Thus, reevaluation of certain morphological, chemical, and physical properties of Taxol-treated microtubules may be necessary. Moreover, our findings suggest a novel mechanism for chemotherapy-induced cytotoxicity in non-dividing cells, with far-reaching medical implications.

  1. Decommissioning of the AVR reactor, concept for the total dismantling

    International Nuclear Information System (INIS)

    Marnet, C.; Wimmers, M.; Birkhold, U.

    1998-01-01

    After more than 21 years of operation, the 15 MWe AVR experimental nuclear power plant with pebble bed high temperature gas-cooled reactor was shout down in 1988. Safestore decommissioning began in 1994. In order to completely dismantle the plant, a concept for Continued dismantling was developed according to which the plant could be dismantled in a step-wise procedure. After each step, there is the possibility to transform the plant into a new state of safe enclosure. The continued dismantling comprises three further steps following Safestore decommissioning: 1. Dismantling the reactor vessels with internals; 2. Dismantling the containment and the auxiliary units; 3. Gauging the buildings to radiation limit, release from the validity range of the AtG (Nuclear Act), and demolition of the buildings. For these steps, various technical procedures and concepts were developed, resulting in a reference concept in which the containment will essentially remain intact (in-situ concept). Over the top of the outer reactor vessel a disassembling area for remotely controlled tools will be erected that tightens on that vessel and can move down on the vessel according to the dismantling progress. (author)

  2. Dismantling of nuclear facilities: the industrial know-how

    International Nuclear Information System (INIS)

    Lellament, R.

    2004-01-01

    Numerous nuclear facilities in laboratories or research reactors have been decommissioned and dismantled over the 2 last decades throughout the world. The valuable feedback experience has allowed nuclear industry to design, upgrade and test specific techniques for dismantling. These techniques are efficient although they have been validated on a reduced number of nuclear power plants. In France only 3 power units have been dismantled: Chinon A1, A2 and Brennilis (EL4) and they are not representative of the real park of EDF'reactors. 6 PWR-type reactors have already been dismantled in the Usa. The results of a survey concerning 26 countries shows that the dismantling cost is around 320 dollars/kWe, it represents 15% of the construction cost which is far from being excessive as it is often read in the media. The dismantling costs can be broken into: - de-construction (25-55%), - wastes from dismantling (17-43%), - security and monitoring (8-13%), - site reclamation (5-13%), and - engineering and project management (5-24%). (A.C.)

  3. Dismantlement and Radioactive Waste Management of DPRK Nuclear Facilities

    International Nuclear Information System (INIS)

    Jooho, W.; Baldwin, G.T.

    2005-01-01

    One critical aspect of any denuclearization of the Democratic People's Republic of Korea (DPRK) involves dismantlement of its nuclear facilities and management of their associated radioactive wastes. The decommissioning problem for its two principal operational plutonium facilities at Yongbyun, the 5MWe nuclear reactor and the Radiochemical Laboratory reprocessing facility, alone present a formidable challenge. Dismantling those facilities will create radioactive waste in addition to existing inventories of spent fuel and reprocessing wastes. Negotiations with the DPRK, such as the Six Party Talks, need to appreciate the enormous scale of the radioactive waste management problem resulting from dismantlement. The two operating plutonium facilities, along with their legacy wastes, will result in anywhere from 50 to 100 metric tons of uranium spent fuel, as much as 500,000 liters of liquid high-level waste, as well as miscellaneous high-level waste sources from the Radiochemical Laboratory. A substantial quantity of intermediate-level waste will result from disposing 600 metric tons of graphite from the reactor, an undetermined quantity of chemical decladding liquid waste from reprocessing, and hundreds of tons of contaminated concrete and metal from facility dismantlement. Various facilities for dismantlement, decontamination, waste treatment and packaging, and storage will be needed. The shipment of spent fuel and liquid high level waste out of the DPRK is also likely to be required. Nuclear facility dismantlement and radioactive waste management in the DPRK are all the more difficult because of nuclear nonproliferation constraints, including the call by the United States for 'complete, verifiable and irreversible dismantlement,' or 'CVID.' It is desirable to accomplish dismantlement quickly, but many aspects of the radioactive waste management cannot be achieved without careful assessment, planning and preparation, sustained commitment, and long completion times

  4. Nuclab Marcoule: a dedicated waste management and dismantling support laboratory

    International Nuclear Information System (INIS)

    Dugne, Olivier; Bec-Espitalier, Lionel; Rosen, Jeremy

    2014-01-01

    Formerly dedicated to plutonium production support, NucLab was renovated to perform a wide range of analyses for dismantling, plant operation and process development activities mainly at Marcoule but also for external clients. The laboratory is a CEA entity in the Nuclear Energy Division. It provides services to several industrial operators (nuclear processes and power plants) in the fields of analytical chemistry, radioactivity measurements, in situ nuclear measurements, decontamination processes, industrial chemistry processes, and waste treatment. NucLab supports research, production, and dismantling activities in all areas of dismantling operations (authors)

  5. Microtubules move the nucleus to quiescence.

    Science.gov (United States)

    Laporte, Damien; Sagot, Isabelle

    2014-01-01

    The nucleus is a cellular compartment that hosts several macro-molecular machines displaying a highly complex spatial organization. This tight architectural orchestration determines not only DNA replication and repair but also regulates gene expression. In budding yeast microtubules play a key role in structuring the nucleus since they condition the Rabl arrangement in G1 and chromosome partitioning during mitosis through their attachment to centromeres via the kinetochore proteins. Recently, we have shown that upon quiescence entry, intranuclear microtubules emanating from the spindle pole body elongate to form a highly stable bundle that spans the entire nucleus. Here, we examine some molecular mechanisms that may underlie the formation of this structure. As the intranuclear microtubule bundle causes a profound re-organization of the yeast nucleus and is required for cell survival during quiescence, we discuss the possibility that the assembly of such a structure participates in quiescence establishment.

  6. The dismantling of nuclear installations: The dismantling of nuclear installations at the CEA's Directorate for nuclear energy; The CEA's sanitation and dismantling works: example of one of the Marcoule UP1 program lots; Research and innovation in sanitation-dismantling; Global optimisation of the management of dismantling radioactive wastes

    International Nuclear Information System (INIS)

    Hauet, Jean-Pierre; Piketty, Laurence; Moitrier, Cyril; Blanchard, Samuel; Soulabaille, Yves; Georges, Christine; Dutzer, Michel; Legee, Frederic

    2016-01-01

    This publication proposes a set of four articles which addresses issues related to the dismantling of nuclear installations in France, notably for the different involved actors such as the CEA and the ANDRA. The authors more particularly address the issue and the general strategy of dismantling within the Directorate for nuclear energy of the CEA; comment the example of one of the Marcoule UP1 program lots to highlight sanitation and dismantling works performed by the CEA; discuss current research and innovation activities within the CEA regarding sanitation and dismantling; and comment how to globally optimise the management of radioactive wastes produced by dismantling activities

  7. Dismantling of nuclear facilities and related problems - Conference proceedings

    International Nuclear Information System (INIS)

    Tournebize, Frederic; Bordet, Didier; Charlety, Philippe; Gore, Thierry; Estrade, Jerome; Lemaire, Hermine; Ginet, Annick; Fabrier, Lionel; Evrard, Lydie; Furois, Timothee; Butez, Marc; Dutzer, Michel; Faure, Vincent; Billarand, Yann; Menuet, Lise; Lahaye, Thierry; Pin, Alain; Mougnard, Philippe; Charavy, Sylvain; Poncet, Philippe; Moggia, Fabrice; Dochy, Arnaud; Benjamin, Patrick; Poncet, Pierre-Emmanuel; Beneteau, Yannick; Richard, Jean-Baptiste; Pellenz, Gilles; Ollivier Dehaye, Catherine; Gerard, Stephane; Denissen, Luc; Davain, Henri; Duveau, Florent; Guyot, Jean-Luc; Ardellier, Luc

    2012-11-01

    The oldest French nuclear facilities, built for some of them in the 1950's for research or power generation purposes, have reached more or less the end of their life. More than 30 facilities have entered the shutdown or dismantling phase, among which 8 reactors of the very first generations of Electricite de France (EdF) reactors. The aim of this two-days conference is to take stock of the present day status and perspectives of the dismantling activity, to approach the question of the management of the wastes produced, and to share experience about large scale operations already carried out. This document gathers the available presentations given during this conference: 1 - the 'Passage' project (F. Tournebize); 2 - CEA-Grenoble: from Louis Neel to key enabling technologies (D. Bordet); 3 - Dismantling actions in France (L. Evrard); 4 - Securing control of long-term charges funding (T. Furois); 5 - Waste disposal projects and their contribution to the management of dismantling wastes (M. Butez); 6 - Specificities linked with dismantling activities (Y. Billarand); 7 - Dismantling safety: the ASN's point of view (L. Evrad); 8 - Labor Ministry viewpoint about the dismantling related questions (T. Lahaye); 9 - Consideration of organizational and human factors in dismantling operations: a new deal in the operators-service providers relation (L. Menuet); 10 - Diploma and training experience (A. Pin); 11 - Glove-boxes dismantling at La Hague plant - status and experience feedback (P. Mougnard); 12 - Dismantling of Siloe reactor (CEA-Grenoble): application of the ALARA approach (P. Charlety); 13 - BR3 - a complex dismantling: the neutron shield tank (NST) in remote operation and indirect vision (L. Denissen); 14 - Cleansing and dismantling of the Phebus PF containment (S. Charavy); 15 - Integration of dismantling at the design and exploitation stages of nuclear facilities (P. Poncet); 16 - Consideration during the design and exploitation stages of dispositions aiming at

  8. Evaluation formulas of manpower needs for dismantling of equipment in FUGEN-3. Dismantling process of the condenser removal

    International Nuclear Information System (INIS)

    Kubota, Shintaro; Izumo, Sari; Usui, Hideo; Kawagoshi, Hiroshi; Koda, Yuya; Nanko, Takashi

    2014-07-01

    Japan Atomic Energy Agency (JAEA) has been developing the PRODIA code which supports to make decommissioning plan and has been preparing evaluation formulas. Manpower needs for the dismantling of the condenser that had conducted from 2010 to 2012 was analyzed and compared with existing evaluation formulas. Applicability of evaluation formulas for a large scale reactor facility was confirmed in dismantling of the heat insulating materials and reliability of unit productivity factor was improved. The evaluation formula of work for clearance was made in dismantling of pipes and supports. Unit productivity factor of dismantling of feed water heaters which is applicable for a large scale reactor facility was derived. For derivation of unit productivity factor, statistically meaningful data was provided from the dismantling of the condenser. Manpower needs for dismantling of the condenser has positive correlation to the weight of equipment and can be described in linear expression. Reliability of each unit productivity factor will be improved with accumulating actual dismantling data in future. (author)

  9. Cleanup and Dismantling of Highly Contaminated Ventilation Systems Using Robotic Tools - 13162

    International Nuclear Information System (INIS)

    Chambon, Frederic; CIZEL, Jean-Pierre; Blanchard, Samuel

    2013-01-01

    The UP1 plant reprocessed nearly 20,000 tons of used natural uranium gas cooled reactor fuel coming from the first generation of civil nuclear reactors in France. Following operating incidents in the eighties, the ventilation system of the continuous dissolution line facility was shut down and replaced. Two types of remote controlled tool carriers were developed to perform the decontamination and dismantling operations of the highly contaminated ventilation duct network. The first one, a dedicated small robot, was designed from scratch to retrieve a thick powder deposit within a duct. The robot, managed and confined by two dedicated glove boxes, was equipped for intervention inside the ventilation duct and used for carrying various cleanup and inspection tools. The second type, consisting of robotic tools developed on the base of an industrial platform, was used for the clean-up and dismantling of the ventilation duct system. Depending on the type of work to be performed, on the shape constraints of the rooms and any equipment to be dismantled, different kinds of robotic tools were developed and installed on a Brokk 40 carrier. After more than ten years of ventilation duct D and D operations at the UP1 plant, a lot of experience was acquired about remote operations. The three main important lessons learned in terms of remote controlled operation are: characterizing the initial conditions as much as reasonably possible, performing non-radioactive full scale testing and making it as simple and modular as possible. (authors)

  10. Cleanup and Dismantling of Highly Contaminated Ventilation Systems Using Robotic Tools - 13162

    Energy Technology Data Exchange (ETDEWEB)

    Chambon, Frederic [AREVA FEDERAL SERVICES, Columbia MD (United States); CIZEL, Jean-Pierre [AREVA BE/NV, Marcoule (France); Blanchard, Samuel [CEA DEN/DPAD, Marcoule (France)

    2013-07-01

    The UP1 plant reprocessed nearly 20,000 tons of used natural uranium gas cooled reactor fuel coming from the first generation of civil nuclear reactors in France. Following operating incidents in the eighties, the ventilation system of the continuous dissolution line facility was shut down and replaced. Two types of remote controlled tool carriers were developed to perform the decontamination and dismantling operations of the highly contaminated ventilation duct network. The first one, a dedicated small robot, was designed from scratch to retrieve a thick powder deposit within a duct. The robot, managed and confined by two dedicated glove boxes, was equipped for intervention inside the ventilation duct and used for carrying various cleanup and inspection tools. The second type, consisting of robotic tools developed on the base of an industrial platform, was used for the clean-up and dismantling of the ventilation duct system. Depending on the type of work to be performed, on the shape constraints of the rooms and any equipment to be dismantled, different kinds of robotic tools were developed and installed on a Brokk 40 carrier. After more than ten years of ventilation duct D and D operations at the UP1 plant, a lot of experience was acquired about remote operations. The three main important lessons learned in terms of remote controlled operation are: characterizing the initial conditions as much as reasonably possible, performing non-radioactive full scale testing and making it as simple and modular as possible. (authors)

  11. Potential mechanisms of resistance to microtubule inhibitors.

    Science.gov (United States)

    Kavallaris, Maria; Annereau, Jean-Philippe; Barret, Jean-Marc

    2008-06-01

    Antimitotic drugs targeting the microtubules, such as the taxanes and vinca alkaloids, are widely used in the treatment of neoplastic diseases. Development of drug resistance over time, however, limits the efficacy of these agents and poses a clinical challenge to long-term improvement of patient outcomes. Understanding the mechanism(s) of drug resistance becomes paramount to allowing for alternative, if not improved, therapeutic options that might circumvent this challenge. Vinflunine, a novel microtubule inhibitor, has shown superior preclinical antitumor activity, and displays a different pattern of resistance, compared with other agents in the vinca alkaloid class.

  12. From dismantling to current scenario in Galician mano commun mountains

    Directory of Open Access Journals (Sweden)

    Francisco García Quiroga

    2013-03-01

    Full Text Available Common mountains are, like seeds, folklore or free software, good examples of commons. They all count on a community to autonomously manage a good in a collaborative manner by establishing rules to guarantee its sustainability. Common mountains in Galicia represent a property modality and goods management breaking the classic dichotomy of pubic against private, by introducing a collective property alternative. The specificity of these mountains is determined by the fact that the holders of the property right are the regular inhabitants of the land; besides, it is important to stress how these communities have been able to create the rules to guarantee the sustainability of this good. Despite the inherent importance of this modality of commons, a process of dismantling has taken place for a long time with the goal of privatizing these goals. This process was reflected in the shortening of the area of these 18.000 mountains from between 1.8 and 2 millions of hectares in Galicia to the current 640.000 hectares. With the analysis of the commons we can understand how communities can assume co responsibility in the sustainability of goods and how this modality is perfectly viable. The study of these goods brings us closer to the idea of new models in social relations and mutual support networks are possible.

  13. GDP-tubulin incorporation into growing microtubules modulates polymer stability.

    Science.gov (United States)

    Valiron, Odile; Arnal, Isabelle; Caudron, Nicolas; Job, Didier

    2010-06-04

    Microtubule growth proceeds through the endwise addition of nucleotide-bound tubulin dimers. The microtubule wall is composed of GDP-tubulin subunits, which are thought to come exclusively from the incorporation of GTP-tubulin complexes at microtubule ends followed by GTP hydrolysis within the polymer. The possibility of a direct GDP-tubulin incorporation into growing polymers is regarded as hardly compatible with recent structural data. Here, we have examined GTP-tubulin and GDP-tubulin incorporation into polymerizing microtubules using a minimal assembly system comprised of nucleotide-bound tubulin dimers, in the absence of free nucleotide. We find that GDP-tubulin complexes can efficiently co-polymerize with GTP-tubulin complexes during microtubule assembly. GDP-tubulin incorporation into microtubules occurs with similar efficiency during bulk microtubule assembly as during microtubule growth from seeds or centrosomes. Microtubules formed from GTP-tubulin/GDP-tubulin mixtures display altered microtubule dynamics, in particular a decreased shrinkage rate, apparently due to intrinsic modifications of the polymer disassembly properties. Thus, although microtubules polymerized from GTP-tubulin/GDP-tubulin mixtures or from homogeneous GTP-tubulin solutions are both composed of GDP-tubulin subunits, they have different dynamic properties, and this may reveal a novel form of microtubule "structural plasticity."

  14. Jose Cabrera dismantling and decommissioning project

    International Nuclear Information System (INIS)

    Ondaro, Manuel

    2013-01-01

    The Jose Cabrera Nuclear Power Plant (NPP) was the first commercial power reactor (Westinghouse 1 loop PWR 510 MWth, 160 MWe) commissioned in Spain and provided the base for future development and training. The reactor construction started in 1963 and it was officially on-line by 1969. The NPP operated from 1969 until 2006 when it became the first reactor to be shut down after completing its operational period. The containment is reinforced concrete with a stainless steel head. In 2010 responsibility for D and D was transferred to Enresa to achieve IAEA level 3 (a green field site available for unrestricted re-uses) by 2017. Of the total of more than 104,000 tons of materials that will be generated during dismantling, it is estimated that only ∼4,000 tons will be radioactive waste, some of which, 40 t are considered as intermediate level long-lived wastes and the rest (3,960 t) will be categorized as VLLW and ILLW. The Project is divided into five phases: Phase 0 - Removal of fuel and preliminary work.. Phase 1 - Preparatory Activities for D and D. complete. Phase 2 - Dismantling of Major Components. Phase 3 - Removal of Auxiliary Installations, Decontamination and Demolition. Phase 4 - Environmental Restoration. Phase 2, is currently ongoing (50% completed). To manage the diverse aspects of decommissioning operations, Enresa uses an internally developed computerized project management tool. The tool, based on knowledge gathered from other Enresa projects, can process operations management, maintenance operations, materials, waste, storage areas, procedures, work permits, operator dose management and records. Enresa considers that communication is important for both internal and external stakeholder relations and can be used to inform, to neutralize negative opinions and attitudes, to remove false expectations and for training. Enresa has created a new multi-purpose area (exhibition/visitor centre) and encourages visits from the public, local schools, local and

  15. Jose Cabrera dismantling and decommissioning project

    Energy Technology Data Exchange (ETDEWEB)

    Ondaro, Manuel [ENRESA, Madrid (Spain)

    2013-07-01

    The Jose Cabrera Nuclear Power Plant (NPP) was the first commercial power reactor (Westinghouse 1 loop PWR 510 MWth, 160 MWe) commissioned in Spain and provided the base for future development and training. The reactor construction started in 1963 and it was officially on-line by 1969. The NPP operated from 1969 until 2006 when it became the first reactor to be shut down after completing its operational period. The containment is reinforced concrete with a stainless steel head. In 2010 responsibility for D and D was transferred to Enresa to achieve IAEA level 3 (a green field site available for unrestricted re-uses) by 2017. Of the total of more than 104,000 tons of materials that will be generated during dismantling, it is estimated that only ∼4,000 tons will be radioactive waste, some of which, 40 t are considered as intermediate level long-lived wastes and the rest (3,960 t) will be categorized as VLLW and ILLW. The Project is divided into five phases: Phase 0 - Removal of fuel and preliminary work.. Phase 1 - Preparatory Activities for D and D. complete. Phase 2 - Dismantling of Major Components. Phase 3 - Removal of Auxiliary Installations, Decontamination and Demolition. Phase 4 - Environmental Restoration. Phase 2, is currently ongoing (50% completed). To manage the diverse aspects of decommissioning operations, Enresa uses an internally developed computerized project management tool. The tool, based on knowledge gathered from other Enresa projects, can process operations management, maintenance operations, materials, waste, storage areas, procedures, work permits, operator dose management and records. Enresa considers that communication is important for both internal and external stakeholder relations and can be used to inform, to neutralize negative opinions and attitudes, to remove false expectations and for training. Enresa has created a new multi-purpose area (exhibition/visitor centre) and encourages visits from the public, local schools, local and

  16. Dismantling of nuclear facilities. From a structural engineering perspective

    International Nuclear Information System (INIS)

    Block, Carsten; Henkel, Fritz-Otto; Bauer, Thomas

    2014-01-01

    The paper summarizes some important aspects, requirements and technical boundary conditions that need to be considered in dismantling projects in the nuclear sector from a structural engineering perspective. Besides general requirements regarding radiation protection, occupational safety, efficiency and cost effectiveness it is important to take into account other conditions which have a direct impact on technical details and the structural assessment of the dismantling project. These are the main aspects highlighted in this paper: - The structural assessment of dismantling projects has to be based on the as-built situation. - The limitations in terms of available equipment and space have to be taken into account. - The structural assessments are often non-standardized engineering evaluations. A selection of five dismantling projects illustrates the various structural aspects. (orig.)

  17. Environmental Assessment for decontamination and dismantlement, Pinellas Plant

    International Nuclear Information System (INIS)

    1995-06-01

    The US Department of Energy (DOE) has prepared an Environmental Assessment (EA) (DOE/EA-1092) of the proposed decontamination and dismantlement of the Pinellas Plant in Largo, Florida. Under the Decontamination and Dismantlement EA, the DOE proposes to clean up facilities, structures, and utilities; dismantle specific structures; and mitigate or eliminate any environmental impacts associated with the cleanup, dismantlement, and related activities. Related activities include utilization of specific areas by new tenants prior to full-scale cleanup. Based on the analyses in the EA, the DOE has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act of 1969. Therefore, the preparation of an environmental impact statement is not required. This report contains the Environmental Assessment, as well as the Finding of No Significant Impact (FONSI)

  18. Wolbachia utilizes host microtubules and Dynein for anterior localization in the Drosophila oocyte.

    Directory of Open Access Journals (Sweden)

    Patrick M Ferree

    2005-10-01

    Full Text Available To investigate the role of the host cytoskeleton in the maternal transmission of the endoparasitic bacteria Wolbachia, we have characterized their distribution in the female germ line of Drosophila melanogaster. In the germarium, Wolbachia are distributed to all germ cells of the cyst, establishing an early infection in the cell destined to become the oocyte. During mid-oogenesis, Wolbachia exhibit a distinct concentration between the anterior cortex and the nucleus in the oocyte, where many bacteria appear to contact the nuclear envelope. Following programmed rearrangement of the microtubule network, Wolbachia dissociate from this anterior position and become dispersed throughout the oocyte. This localization pattern is distinct from mitochondria and all known axis determinants. Manipulation of microtubules and cytoplasmic Dynein and Dynactin, but not Kinesin-1, disrupts anterior bacterial localization in the oocyte. In live egg chambers, Wolbachia exhibit movement in nurse cells but not in the oocyte, suggesting that the bacteria are anchored by host factors. In addition, we identify mid-oogenesis as a period in the life cycle of Wolbachia in which bacterial replication occurs. Total bacterial counts show that Wolbachia increase at a significantly higher rate in the oocyte than in the average nurse cell, and that normal Wolbachia levels in the oocyte depend on microtubules. These findings demonstrate that Wolbachia utilize the host microtubule network and associated proteins for their subcellular localization in the Drosophila oocyte. These interactions may also play a role in bacterial motility and replication, ultimately leading to the bacteria's efficient maternal transmission.

  19. DISMANTLING OF THE FUEL CELL LABORATORY AT RESEARCH CENTRE JUELICH

    International Nuclear Information System (INIS)

    Stahn, B.; Matela, K.; Bensch, D.; Ambos, Frank

    2003-01-01

    The fuel cell laboratory was constructed in three phases and taken into operation in the years 1962 to 1966. The last experimental work was carried out in 1996. After all cell internals had been disassembled, the fuel cell laboratory was transferred to shutdown operation in 1997. Three cell complexes, which differed, in particular, by the type of shielding (lead, cast steel, concrete), were available until then for activities at nuclear components. After approval by the regulatory authority, the actual dismantling of the fuel cell laboratory started in March 2000. The BZ I laboratory area consisted of 7 cells with lead shieldings of 100 to 250 mm thickness. This area was dismantled from April to September 2000. Among other things, approx. 30,000 lead bricks with a total weight of approx. 300 Mg were dismantled and disposed of. The BZ III laboratory area essentially consisted of cells with concrete shieldings of 1200 to 1400 mm thickness. The dismantling of this area started in the fir st half of 2001 and was completed in November 2002. Among other things, approx. 900 Mg of concrete was dismantled and disposed of. Since more than 90 % of the dismantled materials was measurable for clearance, various clearance measurement devices were used during dismantling. The BZ II laboratory area essentially consists of cells with cast steel shieldings of 400 to 460 mm thickness. In September 2002 it was decided to continue using this laboratory area for future tasks. The dismantling of the fuel cell laboratory was thus completed. After appropriate refurbishment, the fuel cell laboratory will probably take up operation again in late 2003

  20. Dismantling and decontamination of the PIVER prototype vitrification facility

    International Nuclear Information System (INIS)

    Jouan, A.

    1989-01-01

    The PIVER facility was dismantled for replacement by a new continuous pilot plant. The more important operation concerns the vitrification cell, containing equipments of the process, for complete disposal and maximum decontamination, requiring dismantling, cutting, conditioning and removal of equipment inside the cell. Manipulators, handling and cutting tools were used. Activity of removed material and irradiation of personal are followed during the work for matching intervention means to operation conditions [fr

  1. Reassessing the Roles of PIN Proteins and Anticlinal Microtubules during Pavement Cell Morphogenesis1[OPEN

    Science.gov (United States)

    Sawchuk, Megan G.; Scarpella, Enrico

    2018-01-01

    The leaf epidermis is a biomechanical shell that influences the size and shape of the organ. Its morphogenesis is a multiscale process in which nanometer-scale cytoskeletal protein complexes, individual cells, and groups of cells pattern growth and define macroscopic leaf traits. Interdigitated growth of neighboring cells is an evolutionarily conserved developmental strategy. Understanding how signaling pathways and cytoskeletal proteins pattern cell walls during this form of tissue morphogenesis is an important research challenge. The cellular and molecular control of a lobed cell morphology is currently thought to involve PIN-FORMED (PIN)-type plasma membrane efflux carriers that generate subcellular auxin gradients. Auxin gradients were proposed to function across cell boundaries to encode stable offset patterns of cortical microtubules and actin filaments between adjacent cells. Many models suggest that long-lived microtubules along the anticlinal cell wall generate local cell wall heterogeneities that restrict local growth and specify the timing and location of lobe formation. Here, we used Arabidopsis (Arabidopsis thaliana) reverse genetics and multivariate long-term time-lapse imaging to test current cell shape control models. We found that neither PIN proteins nor long-lived microtubules along the anticlinal wall predict the patterns of lobe formation. In fields of lobing cells, anticlinal microtubules are not correlated with cell shape and are unstable at the time scales of cell expansion. Our analyses indicate that anticlinal microtubules have multiple functions in pavement cells and that lobe initiation is likely controlled by complex interactions among cell geometry, cell wall stress patterns, and transient microtubule networks that span the anticlinal and periclinal walls. PMID:29192026

  2. Reassessing the Roles of PIN Proteins and Anticlinal Microtubules during Pavement Cell Morphogenesis.

    Science.gov (United States)

    Belteton, Samuel A; Sawchuk, Megan G; Donohoe, Bryon S; Scarpella, Enrico; Szymanski, Daniel B

    2018-01-01

    The leaf epidermis is a biomechanical shell that influences the size and shape of the organ. Its morphogenesis is a multiscale process in which nanometer-scale cytoskeletal protein complexes, individual cells, and groups of cells pattern growth and define macroscopic leaf traits. Interdigitated growth of neighboring cells is an evolutionarily conserved developmental strategy. Understanding how signaling pathways and cytoskeletal proteins pattern cell walls during this form of tissue morphogenesis is an important research challenge. The cellular and molecular control of a lobed cell morphology is currently thought to involve PIN-FORMED (PIN)-type plasma membrane efflux carriers that generate subcellular auxin gradients. Auxin gradients were proposed to function across cell boundaries to encode stable offset patterns of cortical microtubules and actin filaments between adjacent cells. Many models suggest that long-lived microtubules along the anticlinal cell wall generate local cell wall heterogeneities that restrict local growth and specify the timing and location of lobe formation. Here, we used Arabidopsis ( Arabidopsis thaliana ) reverse genetics and multivariate long-term time-lapse imaging to test current cell shape control models. We found that neither PIN proteins nor long-lived microtubules along the anticlinal wall predict the patterns of lobe formation. In fields of lobing cells, anticlinal microtubules are not correlated with cell shape and are unstable at the time scales of cell expansion. Our analyses indicate that anticlinal microtubules have multiple functions in pavement cells and that lobe initiation is likely controlled by complex interactions among cell geometry, cell wall stress patterns, and transient microtubule networks that span the anticlinal and periclinal walls. © 2018 American Society of Plant Biologists. All Rights Reserved.

  3. Reassessing the roles of PIN proteins and anticlinal microtubules during pavement cell morphogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Belteton, Samuel; Sawchuk, Megan G.; Donohoe, Bryon S.; Scarpella, Enrico; Szymanski, Daniel B.

    2017-11-30

    The leaf epidermis is a biomechanical shell that influences the size and shape of the organ. Its morphogenesis is a multiscale process in which nanometer-scale cytoskeletal protein complexes, individual cells, and groups of cells pattern growth and define macroscopic leaf traits. Interdigitated growth of neighboring cells is an evolutionarily conserved developmental strategy. Understanding how signaling pathways and cytoskeletal proteins pattern cell walls during this form of tissue morphogenesis is an important research challenge. The cellular and molecular control of a lobed cell morphology is currently thought to involve PIN-FORMED (PIN)-type plasma membrane efflux carriers that generate subcellular auxin gradients. Auxin gradients were proposed to function across cell boundaries to encode stable offset patterns of cortical microtubules and actin filaments between adjacent cells. Many models suggest that long-lived microtubules along the anticlinal cell wall generate local cell wall heterogeneities that restrict local growth and specify the timing and location of lobe formation. Here we used Arabidopsis reverse genetics and multivariate long-term time-lapse imaging to test current cell shape control models. We found that neither PIN proteins nor microtubules along the anticlinal wall predict the patterns of lobe formation. In fields of lobing cells, anticlinal microtubules are not correlated with cell shape and are unstable at the time scales of cell expansion. Our analyses indicate that anticlinal microtubules have multiple functions in pavement cells, and that lobe initiation is likely controlled by complex interactions among cell geometry, cell wall stress patterns, and transient microtubule networks that span the anticlinal and periclinal walls.

  4. Endoplasmic-reticulum-mediated microtubule alignment governs cytoplasmic streaming.

    Science.gov (United States)

    Kimura, Kenji; Mamane, Alexandre; Sasaki, Tohru; Sato, Kohta; Takagi, Jun; Niwayama, Ritsuya; Hufnagel, Lars; Shimamoto, Yuta; Joanny, Jean-François; Uchida, Seiichi; Kimura, Akatsuki

    2017-04-01

    Cytoplasmic streaming refers to a collective movement of cytoplasm observed in many cell types. The mechanism of meiotic cytoplasmic streaming (MeiCS) in Caenorhabditis elegans zygotes is puzzling as the direction of the flow is not predefined by cell polarity and occasionally reverses. Here, we demonstrate that the endoplasmic reticulum (ER) network structure is required for the collective flow. Using a combination of RNAi, microscopy and image processing of C. elegans zygotes, we devise a theoretical model, which reproduces and predicts the emergence and reversal of the flow. We propose a positive-feedback mechanism, where a local flow generated along a microtubule is transmitted to neighbouring regions through the ER. This, in turn, aligns microtubules over a broader area to self-organize the collective flow. The proposed model could be applicable to various cytoplasmic streaming phenomena in the absence of predefined polarity. The increased mobility of cortical granules by MeiCS correlates with the efficient exocytosis of the granules to protect the zygotes from osmotic and mechanical stresses.

  5. Dismantling and waste management: CEA's strategy and research programs

    International Nuclear Information System (INIS)

    Behar, C.

    2012-01-01

    There are 3 main dismantling operations in CEA. First, the dismantling of the UP1 facility in the Marcoule site. UP1 was a reprocessing plant of nuclear fuels that operated from 1958 to 1997 and is now the biggest dismantling operation in the world. Its dismantling operation follows a 6-step scheme that will end in 2050. Secondly, the Passage project on the Grenoble site that concerns the dismantling of 3 research reactors (Siloette, Melusine and Siloe), of a laboratory dedicated to the analysis of active materials (Lama) and of a station for the processing of waste (Sted). Thirdly the Aladin project that concerns the installations of the Fontenay-aux-Roses site. The dismantling operations are complex because all the first research programs on high activity chemistry and on transuranium elements were performed in Fontenay-aux-Roses facilities and because ancient activities have to leave a clean place to be replaced by new ones. The radioactive waste produced by CEA enter the flow of waste that is normally processed and managed by ANDRA. Only high-activities waste have not yet a definitive solution, they are stored in waiting the opening of a geological repository. CEA leads research programs on the separation and transmutation of minor actinides and on the long-term behaviour of waste packages put in deep geological layers. (A.C.)

  6. Technology and costs for dismantling a Swedish nuclear power plant

    International Nuclear Information System (INIS)

    1979-10-01

    Various estimates concerning the costs of decommissioning a redundant nuclear power reactor to the green fields state are given in the literature. The purpose of this study is to provide background material for the Swedish nuclear power utilities to estimate the costs and time required to dismantle an ASEA-ATOM Boiling Water Reactor. The units Oskarshamn II and Barsebeck 1, both with an installed capacity of approximately 600 MW, serve as reference plants. The time of operation before final shutdown is assumed to be 40 years. Dismantling operations are initiated one year after shutdown. When the dismantling of the plant is finished, the site is to be released for unrestricted use. The costs for dismantling and subsequent final disposal of the radioactive waste are estimated at approximately SEK 500 million (approximately US dollars 120 million) in terms of 1979 prices. The sum includes 25% contingency. The dismantling cost is equivalent to 10-15% of the installation cost of an equivalent new nuclear power plant. The exact percentage is dependent on the interest rate during the construction period. It is shown in the study that a total dismantling can be accomplished in less than five years. This report is a compilation of studies performed by ASEA-ATOM and VBB based on premises given by KBS. The reports from these studies are presented in appendices. (Auth.)

  7. Decontamination and remote dismantling tests in the Itrec reprocessing plant

    International Nuclear Information System (INIS)

    Candelieri, T.; Gerardi, A.; Soffietto, G.

    1993-01-01

    The scope of this research is to evaluate the advantages of the rack removal system in the dismantling of reprocessing installations. The objective of this work is to verify experimentally the possibility of the decontamination of any particular module and the capability of the remote dismantling of components installed in the mobile rack. In particular, the main objective is to develop remotely operated equipment for the dismantling of centrifugal contactors. The decontamination of the equipment which represents the most important preliminary phase of the decommissioning operation, allowed to obtain low-level radioactivity. A supporting programme has been performed in order to collect sufficient data for the project and design of the remote dismantling machine. On the basis of technological cold test results, the project of the dismantling machine's construction has been optimized. Positive results obtained during the hot dismantling operations on the Rack 6 bis attested the effectiveness of the rack removal system as an original design which facilitates decommissioning of reprocessing plants. 2 tabs., 18 figs

  8. Decontamination of the HFR dismantling cell

    International Nuclear Information System (INIS)

    Cloes, K.; Husmann, K.; Hardt, P. von der.

    1976-05-01

    The Commission of the European Communities operates in the Petten Establishment of the Joint Research Centre (EURATOM), a 45 MW light-water cooled materials testing reactor, the HFR. Inside the reactor containment building, on top of a side wing of the main pool, a hot cell had been constructed for the dismantling, of irradiated equipment, and brought into active service in July 1966. Early in 1973, the cell was contaminated by 0.1 to 1 Ci of Po 210 , originating from an irradiation capsule containing Bi impregnated graphite specimens. Due to the elevated radiotoxicity of this isotope, and to numerous potential ways of spreading out the contamination it was decided to stop routine operation of the cell until a satisfactory degree of decontamination had been reached. Two years have been spent for preparation of specialized equipment and thorough clean-up and overhaul work of the cell. It went back into normal operation on February 21st, 1975 and has since then been working very successfully

  9. Method of dismantling a nuclear reactor

    International Nuclear Information System (INIS)

    Shirai, Masato; Hashimoto, Osamu.

    1984-01-01

    Purpose: To enable rapid and simple positioning for a plasma arc torch disposed to the inside of a nuclear reactor main body. Method: After removing the upper semi-spherical portion, fuel portion and control rod portion of a nuclear reactor, a rotary type girder is placed on the upper edge of a cylindrical portion remained after the removal of the upper semi-spherical portion. Then, the upper portion of a supporting rod provided with a swing arm having a plasma arc torch at the top end is situated at the center of the reactor main body. Then, the top end of the support rod is inserted to fix in the housing of control rod drives. Then, the swing arm is actuated to situate the plasma arc torch to a desired position to be cut, whereafter cutting is initiated while rotating the rotary type girder. Thus, plasma arc torch is moved horizontally along an arcuate trace, whereby pipeways, accessories or the likes disposed to the inside of the main body are at first cut and then the cylindrical portion constituting the main body is cut to dismantle the reactor. (Moriyama, K.)

  10. Mobile worksystems for decontamination and dismantlement

    International Nuclear Information System (INIS)

    Osborn, J.; Bares, L.C.; Thompson, B.R.

    1995-01-01

    Many DOE nuclear facilities have aged beyond their useful lifetimes. They need to be decommissioned in order to be safe for human presence in the short term, to eventually recover valuable materials they contain, and ultimately to be transitioned to alternative uses or green field conditions. Decontamination and dismantlement are broad classes of activities that will enable these changes to occur. Most of these facilities - uranium enrichment plants, weapons assembly plants, research and production reactors, and fuel recycling facilities - are dormant, though periodic inspection, surveillance and maintenance activities within them are on-going. DOE estimates that there are over 5000 buildings that require deactivation to reduce the costs of performing such work with manual labor. In the long term, 1200 buildings will be decommissioned, and millions of metric tons of metal and concrete will have to be recycled or disposed of The magnitude of the problem calls for new approaches that are far more cost effective than currently available techniques. This paper describes two technologies that are viable solutions for facility D ampersand D

  11. Mobile worksystems for decontamination and dismantlement

    Energy Technology Data Exchange (ETDEWEB)

    Osborn, J. [Carnegie Mellon Univ., Pittsburgh, PA (United States); Bares, L.C.; Thompson, B.R. [RedZone Robotics, Inc., Pittsburgh, PA (United States)

    1995-10-01

    Many DOE nuclear facilities have aged beyond their useful lifetimes. They need to be decommissioned in order to be safe for human presence in the short term, to eventually recover valuable materials they contain, and ultimately to be transitioned to alternative uses or green field conditions. Decontamination and dismantlement are broad classes of activities that will enable these changes to occur. Most of these facilities - uranium enrichment plants, weapons assembly plants, research and production reactors, and fuel recycling facilities - are dormant, though periodic inspection, surveillance and maintenance activities within them are on-going. DOE estimates that there are over 5000 buildings that require deactivation to reduce the costs of performing such work with manual labor. In the long term, 1200 buildings will be decommissioned, and millions of metric tons of metal and concrete will have to be recycled or disposed of. The magnitude of the problem calls for new approaches that are far more cost effective than currently available techniques. This paper describes a mobile workstation termed ROSIE, which provides remote work capabilities for D&D activities.

  12. Iraq nuclear facility dismantlement and disposal project

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, J R; Danneels, J [Sandia National Laboratories, Albuquerque, NM (United States); Kenagy, W D [U.S. Department of State, Bureau of International Security and Nonproliferation, Office of Nuclear Energy, Safety and Security, Washington, DC (United States); Phillips, C J; Chesser, R K [Center for Environmental Radiation Studies, Texas Tech University, Lubbock, TX (United States)

    2007-07-01

    The Al Tuwaitha nuclear complex near Baghdad contains a significant number of nuclear facilities from Saddam Hussein's dictatorship. Because of past military operations, lack of upkeep and looting there is now an enormous radioactive waste problem at Al Tuwaitha. Al Tuwaitha contains uncharacterised radioactive wastes, yellow cake, sealed radioactive sources, and contaminated metals. The current security situation in Iraq hampers all aspects of radioactive waste management. Further, Iraq has never had a radioactive waste disposal facility, which means that ever increasing quantities of radioactive waste and material must be held in guarded storage. The Iraq Nuclear Facility Dismantlement and Disposal Program (the NDs Program) has been initiated by the U.S. Department of State (DOS) to assist the Government of Iraq (GOI) in eliminating the threats from poorly controlled radioactive materials, while building human capacities so that the GOI can manage other environmental cleanups in their country. The DOS has funded the International Atomic Energy Agency (IAEA) to provide technical assistance to the GOI via a Technical Cooperation Project. Program coordination will be provided by the DOS, consistent with U.S. and GOI policies, and Sandia National Laboratories will be responsible for coordination of participants and for providing waste management support. Texas Tech University will continue to provide in-country assistance, including radioactive waste characterization and the stand-up of the Iraq Nuclear Services Company. The GOI owns the problems in Iraq and will be responsible for the vast majority of the implementation of the NDs Program. (authors)

  13. Cleaning of dismantled metals by electropolishing

    International Nuclear Information System (INIS)

    Wei, T.Y.; Chung, Z.J.; Lu, D.L.; Hsieh, J.C.

    1995-01-01

    A project of cleaning dismantled metals is going on at INER. The test work has been performed. Results showed that the activity decreased from 45 microSv/h to background level after 20 minutes electrolytic polishing. These cleaned metals could be reused through melting and fabricating. These metals could also be classified as BRC waste to facilitate the waste management if they can pass the identification and be admitted by the government authority. In order to achieve the planned target, some electro-decontamination facilities have been established. An automatic electropolishing facility with six cells was designed to clean the contaminated metals in plate type with dimensions less than 50 cm x 50 cm. Another automatic electropolishing facility was specially designed for treating the contaminated pipes. In addition, mobile electropolishing facilities were also established for large pieces of metal and some fixed equipment. In this cleaning project, a practical recycling and treatment method for electrolyte has been developed in order to comply with the requirement of secondary waste minimization

  14. Dismantling method for nuclear fuel assembly

    International Nuclear Information System (INIS)

    Yamazaki, Shuji; Kato, Akihiro; Yoshida, Masafumi.

    1993-01-01

    An upper nozzle is detached from a control rod guide tube and an instrumentation tube. Subsequently, slots (slits) having a predetermined width are formed longitudinally at enlarged diameter portions of the control rod guide tube and the instrumentation tube. Then, the control rod guide tube and the instrumentation tube are separated from a lower nozzle, and pulled out from the lattice space of each of the support lattices. Thereafter, a predetermined key is inserted to a key insertion window formed at each of the support lattices, to distort a spring and take the fuel rod out of the lattice space of each of the support lattices. With such procedures, when the control rod guide tube and the instrumentation tube are pulled out of the lattice space of the support lattice, the enlarged diameter portion is narrowed to reduce the diameter, thereby enabling to take them out easily. Accordingly, since the space for inserting the key can be ensured, the nuclear fuel assemblies can easily be dismantled. In addition, fuel rods can be taken out smoothly and in an intact state. (I.N.)

  15. Dismantling the Curriculum in Higher Education

    Directory of Open Access Journals (Sweden)

    Richard Hall

    2016-04-01

    Full Text Available The higher education curriculum in the global North is increasingly co-opted for the production of measurable outcomes, framed by determinist narratives of employability and enterprise. Such co-option is immanent to processes of financialisation and marketisation, which encourage the production of quantifiable curriculum activities and tradable academic services. Yet the university is also affected by global socio-economic and socio-environmental crises, which can be expressed as a function of a broader crisis of social reproduction or sociability. As the labour of academics and students is increasingly driven by a commodity-valuation rooted in the measurement of performance, the ability for academics and students to respond to crises from inside the university is constrained by the market. This article argues that in understanding the relationship between the university and society, and in responding to a crisis of sociability, revealing the bounded nature of the curriculum is central. One possible way to address this crisis is by re-imagining the university through the co-operative practices of groups like the Dismantling the Masters House community and the Social Science Centre. Such an exploration, rooted in the organising principles of the curriculum, asks educators to consider how their curriculum reproduces an on-going colonisation by Capital. It is argued that such work enables a re-imagination of higher education that is rooted in a co-operative curriculum, and which might enable activist-educators to build an engaged curriculum, through which students and academics no longer simply learn to internalise, monitor and manage their own alienation.

  16. Dismantling at the CEA's Nuclear Energy Division: strategy and programmes

    International Nuclear Information System (INIS)

    Lecomte, C.; Prunele, D. de; Rozain, J.P.; Nokhamzon, J.G.; Tallec, M.

    2008-01-01

    The CEA's Nuclear Energy Division (DEN) nuclear facilities currently include seventeen reactors and thirty six other miscellaneous facilities, particularly laboratories, fuel processing units and facilities specific to waste management. Some of these are currently being dismantled or must be dismantled soon so that the DEN, the Nuclear Energy Division, can construct new equipment and thus have available a range of R and D facilities in line with the issues of the nuclear industry of the future. At CEA, the first nuclear facility dismantling operations go back several dozen years and involve numerous and varied facilities. The first operations of any significance took place in the 1960's and 1970's and covered, for example, the first plutonium plant at Fontenay-aux-Roses (total dismantling) and small research reactors or critical models - CESAR and PEGGY at Cadarache and MINERVE at Fontenay-aux Roses (civil engineering cleaned up and kept). At La Hague, the dismantling of AT1, a pilot workshop used by the CEA during the 1970's to process irradiated fuels from fast neutron reactors, was completed in March 2001 (IAEA former stage 3, excluding civil engineering demolition). On the other hand, during this period of first dismantling, the intermediate-sized reactors (G1, Rapsodie) were only partially dismantled after shut down, mainly due to the lack of graphite and sodium waste management routes at the time. About twenty facilities were thus dealt with up to 2001, in other words about half of all the nuclear facilities shut down permanently before this date. (authors)

  17. The Microtubule Regulatory Protein Stathmin Is Required to Maintain the Integrity of Axonal Microtubules in Drosophila

    Science.gov (United States)

    Duncan, Jason E.; Lytle, Nikki K.; Zuniga, Alfredo; Goldstein, Lawrence S. B.

    2013-01-01

    Axonal transport, a form of long-distance, bi-directional intracellular transport that occurs between the cell body and synaptic terminal, is critical in maintaining the function and viability of neurons. We have identified a requirement for the stathmin (stai) gene in the maintenance of axonal microtubules and regulation of axonal transport in Drosophila . The stai gene encodes a cytosolic phosphoprotein that regulates microtubule dynamics by partitioning tubulin dimers between pools of soluble tubulin and polymerized microtubules, and by directly binding to microtubules and promoting depolymerization. Analysis of stai function in Drosophila , which has a single stai gene, circumvents potential complications with studies performed in vertebrate systems in which mutant phenotypes may be compensated by genetic redundancy of other members of the stai gene family. This has allowed us to identify an essential function for stai in the maintenance of the integrity of axonal microtubules. In addition to the severe disruption in the abundance and architecture of microtubules in the axons of stai mutant Drosophila , we also observe additional neurological phenotypes associated with loss of stai function including a posterior paralysis and tail-flip phenotype in third instar larvae, aberrant accumulation of transported membranous organelles in stai deficient axons, a progressive bang-sensitive response to mechanical stimulation reminiscent of the class of Drosophila mutants used to model human epileptic seizures, and a reduced adult lifespan. Reductions in the levels of Kinesin-1, the primary anterograde motor in axonal transport, enhance these phenotypes. Collectively, our results indicate that stai has an important role in neuronal function, likely through the maintenance of microtubule integrity in the axons of nerves of the peripheral nervous system necessary to support and sustain long-distance axonal transport. PMID:23840848

  18. Effects of ultraviolet radiation on microtubule organisation and morphogenesis in plants

    International Nuclear Information System (INIS)

    Staxen, I.

    1994-09-01

    The involvement of the cytoskeleton in the development of somatic embryos was studied in Larix x eurolepis. Protoplasts were isolated from both somatic embryo-regenerating and non-generating cultures and fractionated on a discontinuous Percoll density gradient, whereby a highly embryogenic protoplast fraction could be enriched. Protoplasts of two cell lines of Larix eurolepis, one with regenerating potential and one lacking this potential, were compared. In contrast to the non-regenerating line were a protoplast-like organisation of the cortical microtubules was maintained, re-organisation of this microtubular network occurred in the regenerable line after only three days of culture, indicating that organised growth was occurring. However, this early organisation of cortical microtubules may not always be a valid marker for regenerable and non-regenerable material. In order to investigate the effect of ultraviolet-B (UV-B, 280-320 nm) radiation on the microtubule cytoskeleton, protoplasts were isolated from leaves of Petunia hybrida and subjected to four different doses of UV-B radiation. The organisation of the microtubules and the progression of the cells through the cell cycle was observed at 0, 24, 48 and 72 h after irradiation. UV-B induced breaks in the cortical microtubules resulting in shorter fragments with increasing amounts of radiation. Also, the division of the protoplasts was delayed, which was related to the absence of an microtubule network. Whole Petunia plants were grown in growth chambers in the presence and absence of UV-B. The plants responded to UV-B with increased rates of CO 2 assimilation, a 60% increase in UV-screening compounds and the changes in the morphology of the leaves that were reflected in a 70-100% increase in leaf area and 20% decrease in leaf thickness. The microtubules of the epidermal cells was not affected by UV-B, nor was the number of epidermal cells (per unit area). The increase in leaf area in the UV-treated plants

  19. Dismantlement and Radioactive Waste Management of DPRK Nuclear Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Jooho, W.; Baldwin, G. T.

    2005-04-01

    One critical aspect of any denuclearization of the Democratic People’s Republic of Korea (DPRK) involves dismantlement of its nuclear facilities and management of their associated radioactive wastes. The decommissioning problem for its two principal operational plutonium facilities at Yongbyun, the 5MWe nuclear reactor and the Radiochemical Laboratory reprocessing facility, alone present a formidable challenge. Dismantling those facilities will create radioactive waste in addition to existing inventories of spent fuel and reprocessing wastes. Negotiations with the DPRK, such as the Six Party Talks, need to appreciate the enormous scale of the radioactive waste management problem resulting from dismantlement. The two operating plutonium facilities, along with their legacy wastes, will result in anywhere from 50 to 100 metric tons of uranium spent fuel, as much as 500,000 liters of liquid high-level waste, as well as miscellaneous high-level waste sources from the Radiochemical Laboratory. A substantial quantity of intermediate-level waste will result from disposing 600 metric tons of graphite from the reactor, an undetermined quantity of chemical decladding liquid waste from reprocessing, and hundreds of tons of contaminated concrete and metal from facility dismantlement. Various facilities for dismantlement, decontamination, waste treatment and packaging, and storage will be needed. The shipment of spent fuel and liquid high level waste out of the DPRK is also likely to be required. Nuclear facility dismantlement and radioactive waste management in the DPRK are all the more difficult because of nuclear nonproliferation constraints, including the call by the United States for “complete, verifiable and irreversible dismantlement,” or “CVID.” It is desirable to accomplish dismantlement quickly, but many aspects of the radioactive waste management cannot be achieved without careful assessment, planning and preparation, sustained commitment, and long

  20. Non-equilibrium assembly of microtubules: from molecules to autonomous chemical robots.

    Science.gov (United States)

    Hess, H; Ross, Jennifer L

    2017-09-18

    Biological systems have evolved to harness non-equilibrium processes from the molecular to the macro scale. It is currently a grand challenge of chemistry, materials science, and engineering to understand and mimic biological systems that have the ability to autonomously sense stimuli, process these inputs, and respond by performing mechanical work. New chemical systems are responding to the challenge and form the basis for future responsive, adaptive, and active materials. In this article, we describe a particular biochemical-biomechanical network based on the microtubule cytoskeletal filament - itself a non-equilibrium chemical system. We trace the non-equilibrium aspects of the system from molecules to networks and describe how the cell uses this system to perform active work in essential processes. Finally, we discuss how microtubule-based engineered systems can serve as testbeds for autonomous chemical robots composed of biological and synthetic components.

  1. Development of multi-functional telerobotic systems for reactor dismantlement

    International Nuclear Information System (INIS)

    Fujii, Yoshio; Usui, Hozumi; Shinohara, Yoshikuni

    1992-01-01

    This report summarizes technological features of advanced telerobotic systems for reactor dismantling application developed at the Japan Atomic Energy Research Institute. Taking into consideration the special environmental conditions in reactor dismantling, major effort was made to develop multifunctional telerobotic system of high reliability which can be used to perform various complex tasks in an unstructured environment and operated in an easy and flexible manner. The system development was carried out through constructing three systems in seccession; a light-duty and a heavy-duty system as a prototype system for engineering test in cold environment, and a demonstration system for practical on-site application to dismantling highly radioactive reactor internals of an experimental boiling water reactor JPDR (Japan Power Demonstration Reactor). Each system was equipped with one or two amphibious manipulators which can be operated in either a push-button manual, a bilateral master-slave, a teach-and-playback or a programmed control mode. Different scheme was adopted in each system at designing the manipulator, transporter and man-machine interface so as to compare their advantages and disadvantages. According to the JPDR decommissioning program, the demonstration system was successfully operated to dismantle a portion of the radioactive reactor internals of the JPDR, which used underwater plasma arc cutting method and proved the usefulness of the multi-functional telerobotic system for reducing the occupational hazards and enhancing the work efficiency in the course of dismantling highly radioactive reactor components. (author)

  2. Overall strategy of Creys Malville power station dismantling

    International Nuclear Information System (INIS)

    Alphonse, P.

    2002-01-01

    The power station was stopped by a government decision following the elections in 1997. This shutdown was then made official by a letter dated April 1998 and the decree of December 1998. This was a non-technical shutdown and as such had not been envisaged; there has been no early warning. Current dismantling strategy: The studies leading to shutdown and then dismantling were engaged in 1998 based on a scenario with a status corresponding to IAEA level 2 until 2046. In 2001, EDF management made the decision to dismantle all the first generation power stations and Creys Malville between now and 2025. It should be noted that the presence of strongly irradiated stellite in the Creys Malville reactor would still require remote systems for working in the reactor block after 2046. The sequence of operations dictated by the dismantling strategy is as follows: eliminate the risks as soon as possible and in particular the risk related to the sodium, 3300 tonnes of which is kept in liquid form in the reactor vessel; dismantle the most active parts which are too radioactive to be sent to the existing or planned storage centres. This may lead to on-site storage to allow decay to occur before sending to a storage centre; planning of the work interventions in order to limit the costs

  3. Dismantling and waste managing benefit from digital technologies

    International Nuclear Information System (INIS)

    Moitrier, C.

    2017-01-01

    Dismantling is a very important challenge for nuclear industry as its success will prove the ability of the industry to deal with all the stages of a nuclear power plant from design to the end. A dismantling project is constraint by costs, time, feasibility, safety and environment protection and all of this implies a perfect knowledge of both the initial state of the facility at the beginning of the dismantling and the supply chain to avoid delays and extra-costs. Digital tools have a very important role to play as a provider of a 3-dimensional digital twin of the facility. This digital model allows: a remote preparation of the dismantling actions, to assess and optimize the radiation exposure during the intervention, to simulate various scenarios and select the most adequate, to ease collaborative work between various teams, to assess the volume and kind of waste at a very early stage of the dismantling, and to train operators and workers for x. (A.C.)

  4. Microtubules Growth Rate Alteration in Human Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Irina B. Alieva

    2010-01-01

    Full Text Available To understand how microtubules contribute to the dynamic reorganization of the endothelial cell (EC cytoskeleton, we established an EC model expressing EB3-GFP, a protein that marks microtubule plus-ends. Using this model, we were able to measure microtubule growth rate at the centrosome region and near the cell periphery of a single human EC and in the EC monolayer. We demonstrate that the majority of microtubules in EC are dynamic, the growth rate of their plus-ends is highest in the internal cytoplasm, in the region of the centrosome. Growth rate of microtubule plus-ends decreases from the cell center toward the periphery. Our data suggest the existing mechanism(s of local regulation of microtubule plus-ends growth in EC. Microtubule growth rate in the internal cytoplasm of EC in the monolayer is lower than that of single EC suggesting the regulatory effect of cell-cell contacts. Centrosomal microtubule growth rate distribution in single EC indicated the presence of two subpopulations of microtubules with “normal” (similar to those in monolayer EC and “fast” (three times as much growth rates. Our results indicate functional interactions between cell-cell contacts and microtubules.

  5. Dinitroaniline herbicide resistance and the microtubule cytoskeleton.

    Science.gov (United States)

    Anthony; Hussey

    1999-03-01

    Dinitroaniline herbicides have been used for pre-emergence weed control for the past 25 years in cotton, soybean, wheat and oilseed crops. Considering their long persistence and extensive use, resistance to dinitroanilines is fairly rare. However, the most widespread dinitroaniline-resistant weeds, the highly resistant (R) and the intermediate (I) biotypes of the invasive goosegrass Eleusine indica, are now infesting more than 1000 cotton fields in the southern states of the USA. The molecular basis of this resistance has been identified, and found to be a point mutation in a major microtubule cytoskeletal protein, alpha-tubulin. These studies have served both to explain the establishment of resistance and to reveal fundamental properties of tubulin gene expression and microtubule structure.

  6. Features of rotary pump diagnostics without dismantling

    Directory of Open Access Journals (Sweden)

    Sergeev K. О.

    2017-12-01

    Full Text Available In ship power plants, rotor pumps have become very popular providing the transfer of various viscous fluids: fuels, oils, etc. Like all ship's mechanisms, pumps need proper maintenance and monitoring of technical condition. The most expedient is maintenance and repair carried out according to the results of dismantling diagnosis. The methods of vibrodiagnostics are mostly widespread for the diagnosis of pumps. Vibrodiagnosis of rotary pumps has a number of features due to the nature and condition of pumped fluids. The norms of the Russian Maritime Register of Shipping are used for setting standards of vibration and diagnostics of the rotary pumps' technical condition. To clarify the features of vibration diagnostics of rotary pumps some measurements have been made on a special bench that simulates various modes of ship's pumps' operation: different pressure in the system and temperature of the pumped medium. As a result of measurements one-third octave and narrow-band vibration spectra of pumps have been obtained at various developed pressures and temperatures of the pumped fluid. The performed analysis has shown that the RMRS norms for diagnostics of ship rotary pumps have insufficient informative value inasmuch they do not take into account the dependence of the vibrational signal spectrum on the developed pressure and temperature of the pumped fluid. The nature of the received signals shows that the levels of a third-octave spectrum of the vibration velocity depend significantly on the temperature of the pumped fluids, this fact must be taken into account when applying the RMRS norms. The fluid temperature has a great influence on the nature of the narrow-band vibration acceleration spectrum in the area of medium frequencies, less influence – on the nature of the vibration velocity spectrum. The conclusions have been drawn about the advisability of using the narrow-band vibration spectra and the envelope spectra of the high

  7. Development of telerobotic manipulators for reactor dismantling work

    International Nuclear Information System (INIS)

    Shinohara, Yoshikuni; Usui, Hozumi; Fujii, Yoshio

    1991-01-01

    This paper describes the amphibious electrical manipulators JARM-10, JART-25, JART-100 and JARM-25 which were developed in the program of reactor decommissioning technology development carried out by the Japan Atomic Energy Research Institute. They are multi-functional telerobotic light-duty (10 and 25 daN) and heavy-duty (100 daN) Manipulators which can be used in hostile environments in reactor dismantling work such as high radiation, underwater work and electrical noise. Each manipulator can be operated in either a bilateral master-slave, a teach-and-playback or a programmed control mode. By combining these modes appropriately, it is possible to perform complex tasks of remote handling. The usefulness of the telerobotic systems for dismantling nuclear reactors has been demonstrated by successful application of the JARM-25 for remote underwater dismantlement of highly radioactive reactor internals of complex form of an experimental nuclear power reactor. (author)

  8. Decommissioning and dismantling of the reprocessing plant Karlsruhe

    International Nuclear Information System (INIS)

    Eiben, K.; Fritz, P.

    1995-01-01

    Reprocessing activities were discontinued in late 1990. The facility was drained and rinsed, and 80 m3 of HLWC have since been stored in special tanks, awaiting vitrification. Decommissioning work is scheduled to proceed in six phases. The reprocessing areas of the facility will be prepared for release from radiological control and dismantled in the first phase. The remaining facilities can be deregulated, and storage tanks dismantled, only after termination of phase 1. The goal of the following phase is clearance from radiological control of all controlled areas, and the last phase is to cover dismantling of all buildings and restoration of a green field site. The overall costs of these activities are estimated to amount to DM 1.657 million. The article explains the contents of the first permits for decommissioning as well as the documents prepared for planning of work and licence application. (orig./HP) [de

  9. Evaluation of worker's dose on a virtual dismantling environment

    International Nuclear Information System (INIS)

    Park, Hee Seong; Kim, Sung Hyun; Park, Byung Suk; Yoon, Ji Sup

    2007-01-01

    The motivation of this study is to provide a basis for a minimization of worker's dose during dismantling activities. In the present study, we proposed methods for identifying an existence of radioactivity which is contained in the dismantling objects and for evaluating a worker's dose under a virtual dismantling environment. To evaluate a worker's external dose, the shape of the exposure room in the KRR 2(Korean Research Reactor TRIGA MARK III) by 3D CAD was created and the radiation dose surrounding the facility by using MCNP- 4C(Monte Carlo N-Particle-4C) was calculated. The radiation field of the exposure room was visualized three dimensionally by using the radiation dose that was obtained by the code

  10. REUSE OF AUTOMOTIVE COMPONENTS FROM DISMANTLED END OF LIFE VEHICLES

    Directory of Open Access Journals (Sweden)

    Piotr NOWAKOWSKI

    2013-12-01

    Full Text Available The problem of recycling end of life automotive vehicles is serious worldwide. It is one of the most important streams of waste in developed countries. It has big importance as recycling potential of raw materials content in automotive vehicles is valuable. Different parts and assemblies after dismantling can also be reused in vehicles where replacement of specific component is necessary. Reuse of the components should be taken into consideration in selecting the vehicles dismantling strategy. It also complies with European Union policy concerning end of life vehicles (ELV. In the paper it is presented systematic approach to dismantling strategies including disassembly oriented on further reuse of components. It is focused on decision making and possible benefits calculation from economic and environmental point of view.

  11. The Role of Molecular Microtubule Motors and the Microtubule Cytoskeleton in Stress Granule Dynamics

    Directory of Open Access Journals (Sweden)

    Kristen M. Bartoli

    2011-01-01

    Full Text Available Stress granules (SGs are cytoplasmic foci that appear in cells exposed to stress-induced translational inhibition. SGs function as a triage center, where mRNAs are sorted for storage, degradation, and translation reinitiation. The underlying mechanisms of SGs dynamics are still being characterized, although many key players have been identified. The main components of SGs are stalled 48S preinitiation complexes. To date, many other proteins have also been found to localize in SGs and are hypothesized to function in SG dynamics. Most recently, the microtubule cytoskeleton and associated motor proteins have been demonstrated to function in SG dynamics. In this paper, we will discuss current literature examining the function of microtubules and the molecular microtubule motors in SG assembly, coalescence, movement, composition, organization, and disassembly.

  12. Atomic Energy Commission (CEA) dismantling experience review and perspectives

    International Nuclear Information System (INIS)

    Barre, J.Y.

    1992-01-01

    Reorganization and dismantling have been part of the CEA's facility renewal process for more than twenty years now. Many facilities have already been downrated or will be in the near future. The strategy developed so far is founded on acquired experience, on the basis of which it may be said that: nuclear facilities are reversible in full and strict compliance with safety and security rules; a field of competence has been developed that will help French industries to land on their feet when the time comes on the dismantling market; public opinion has been informed as to the soundness of the energy alternatives chosen

  13. Plasma membrane factor XIIIA transglutaminase activity regulates osteoblast matrix secretion and deposition by affecting microtubule dynamics.

    Directory of Open Access Journals (Sweden)

    Hadil F Al-Jallad

    2011-01-01

    Full Text Available Transglutaminase activity, arising potentially from transglutaminase 2 (TG2 and Factor XIIIA (FXIIIA, has been linked to osteoblast differentiation where it is required for type I collagen and fibronectin matrix deposition. In this study we have used an irreversible TG-inhibitor to 'block -and-track' enzyme(s targeted during osteoblast differentiation. We show that the irreversible TG-inhibitor is highly potent in inhibiting osteoblast differentiation and mineralization and reduces secretion of both fibronectin and type I collagen and their release from the cell surface. Tracking of the dansyl probe by Western blotting and immunofluorescence microscopy demonstrated that the inhibitor targets plasma membrane-associated FXIIIA. TG2 appears not to contribute to crosslinking activity on the osteoblast surface. Inhibition of FXIIIA with NC9 resulted in defective secretory vesicle delivery to the plasma membrane which was attributable to a disorganized microtubule network and decreased microtubule association with the plasma membrane. NC9 inhibition of FXIIIA resulted in destabilization of microtubules as assessed by cellular Glu-tubulin levels. Furthermore, NC9 blocked modification of Glu-tubulin into 150 kDa high-molecular weight Glu-tubulin form which was specifically localized to the plasma membrane. FXIIIA enzyme and its crosslinking activity were colocalized with plasma membrane-associated tubulin, and thus, it appears that FXIIIA crosslinking activity is directed towards stabilizing the interaction of microtubules with the plasma membrane. Our work provides the first mechanistic cues as to how transglutaminase activity could affect protein secretion and matrix deposition in osteoblasts and suggests a novel function for plasma membrane FXIIIA in microtubule dynamics.

  14. Microtubules are organized independently of the centrosome in Drosophila neurons

    Directory of Open Access Journals (Sweden)

    Nguyen Michelle M

    2011-12-01

    Full Text Available Abstract Background The best-studied arrangement of microtubules is that organized by the centrosome, a cloud of microtubule nucleating and anchoring proteins is clustered around centrioles. However, noncentrosomal microtubule arrays are common in many differentiated cells, including neurons. Although microtubules are not anchored at neuronal centrosomes, it remains unclear whether the centrosome plays a role in organizing neuronal microtubules. We use Drosophila as a model system to determine whether centrosomal microtubule nucleation is important in mature neurons. Results In developing and mature neurons, centrioles were not surrounded by the core nucleation protein γ-tubulin. This suggests that the centrioles do not organize functional centrosomes in Drosophila neurons in vivo. Consistent with this idea, centriole position was not correlated with a specific region of the cell body in neurons, and growing microtubules did not cluster around the centriole, even after axon severing when the number of growing plus ends is dramatically increased. To determine whether the centrosome was required for microtubule organization in mature neurons, we used two approaches. First, we used DSas-4 centriole duplication mutants. In these mutants, centrioles were present in many larval sensory neurons, but they were not fully functional. Despite reduced centriole function, microtubule orientation was normal in axons and dendrites. Second, we used laser ablation to eliminate the centriole, and again found that microtubule polarity in axons and dendrites was normal, even 3 days after treatment. Conclusion We conclude that the centrosome is not a major site of microtubule nucleation in Drosophila neurons, and is not required for maintenance of neuronal microtubule organization in these cells.

  15. Radiation protection aspects of dismantling and decommissioning of Uranium Mining of Andujar (Spain)

    International Nuclear Information System (INIS)

    Ortiz Ramis, M.T.; Garcia-Bermejo Fernandez, R.; Martin Palomo, N.

    1995-01-01

    This study analyzes the radiation protection aspects during the decommissioning and dismantling of uranium mining in Andujar (Spain). The application during dismantling's mining, the transfer factor of natural radioactive isotopes and the application during the sterile movements are presented

  16. 49 CFR 1242.42 - Administration, repair and maintenance, machinery repair, equipment damaged, dismantling retired...

    Science.gov (United States)

    2010-10-01

    ... repair, equipment damaged, dismantling retired property, fringe benefits, other casualties and insurance, lease rentals, joint facility rents, other rents, depreciation, joint facility, repairs billed to others... maintenance, machinery repair, equipment damaged, dismantling retired property, fringe benefits, other...

  17. Effect of radiation on microtubule structure in cancer cells

    International Nuclear Information System (INIS)

    Tripath, Shambhoo Sharan; Panda, Dulal; Jayakumar, S.; Maikho, Thoh; Sandur, Santosh Kumar

    2017-01-01

    Microtubules (MT) are dynamic structural cellular components. In proliferating cells, they are essential components in cell division through the formation of the mitotic spindle. Radiotherapy is an integral part of cancer treatment for most of the solid cancers. Scanty data exists in the literature related to how ionizing radiation affects microtubule reorganization in tumor cells. In the present study, breast cancer cell line (MCF-7 cells) was exposed to different doses of radiation (2-10Gy). Cells were cultured for 24 h, fixed and stained with antitubulin antibody and subjected to immunofluorescence microscopy. In another experiment, cells were subjected to cold treatment for 5 min or 30 min for studying the disassembly of microtubules after 24 h of irradiation. Further, these cells were incubated at 37°C for 20 min for studying the reassembly of microtubules. Acetylation of microtubule was also examined after exposure of cells to radiation. Experiments were also performed by combining radiation with low concentration of CXI-Benzo 84 (MT destabilizing agent 1 and 2.5 uM). Exposure of MCF-7 cells to radiation lead to destabilization of microtubules. Interestingly, destabilization of microtubule was faster upon cold treatment in irradiated group as compared to control group. These cells failed to re-stabilize at 37°C. Radiation also reduced the acetylation level of microtubule. Combination treatment of CXI-Benzo 84 with radiation exhibited additive effect in terms of depolymerization of MT. Our results suggest that ionizing radiation indeed modulates microtubule dynamics. (author)

  18. Producing Conditional Mutants for Studying Plant Microtubule Function

    Energy Technology Data Exchange (ETDEWEB)

    Richard Cyr

    2009-09-29

    The cytoskeleton, and in particular its microtubule component, participates in several processes that directly affect growth and development in higher plants. Normal cytoskeletal function requires the precise and orderly arrangement of microtubules into several cell cycle and developmentally specific arrays. One of these, the cortical array, is notable for its role in directing the deposition of cellulose (the most prominent polymer in the biosphere). An understanding of how these arrays form, and the molecular interactions that contribute to their function, is incomplete. To gain a better understanding of how microtubules work, we have been working to characterize mutants in critical cytoskeletal genes. This characterization is being carried out at the subcellular level using vital microtubule gene constructs. In the last year of funding colleagues have discovered that gamma-tubulin complexes form along the lengths of cortical microtubules where they act to spawn new microtubules at a characteristic 40 deg angle. This finding complements nicely the finding from our lab (which was funded by the DOE) showing that microtubule encounters are angle dependent; high angles encounters results in catastrophic collisions while low angle encounters result in favorable zippering. The finding of a 40 deg spawn of new microtubules from extant microtubule, together with aforementioned rules of encounters, insures favorable co-alignment in the array. I was invited to write a New and Views essay on this topic and a PDF is attached (News and Views policy does not permit funding acknowledgments and so I was not allowed to acknowledge support from the DOE).

  19. Lessons learned. Optimization of the plant structure at the beginning of the dismantling process

    International Nuclear Information System (INIS)

    Sesterhenn, Kurt

    2008-01-01

    The processes of shutdown and dismantling of the NPP Muehlheim-Kaerlich included several steps: conservation operation including fuel element removal, decontamination and radiological characterization, conservation of components that may still be used, removal and disposal of operating supply items, preparation of concepts for the dismantling process and realization of dismantling. The authors describe in detail the safety concept, the waste tracking program, the operational organization and reduction of area subject to radiological surveillance during the dismantling and renaturation project.

  20. The further development and evaluation of an automatic dismantler of short staple ring-spun yarns

    CSIR Research Space (South Africa)

    Fassihi, A

    2014-07-01

    Full Text Available Information System (AFIS) single fiber length tests, the fibers from automatically dismantled ring-spun cotton yarns are very similar in their properties to those dismantled by hand (manually). It was also found that, at a speed of 2 m/min, the yarn dismantler...

  1. Provisions for the dismantling of nuclear facilities are sufficient

    International Nuclear Information System (INIS)

    Le Ngoc, B.

    2016-01-01

    The European Union has assessed the provisions made by the nuclear plant operators to face the future costs of dismantling. The United-Kingdom and the Netherlands are the single E.U. members to have provisions covering the whole of the expenses (respectively 100% and 94%). The figure for France is very low 33% (far below the European average of 56%). According to French authorities the provisions for the dismantling of nuclear facilities are strictly defined by law: they must be made progressively till the decommissioning and they must be composed by dedicated assets. The costs of the dismantling is regularly re-assessed for taking into account technological progress and changes in regulation. Furthermore the French system limits the period in which provisions are made to the initial operating life of the plant: mostly 40 years which is a prudent measure. In other E.U. members like Germany, the provisions are not covered by dedicated assets which might endanger the capacity of the operator to face the future costs. The progressiveness of the French systems of provision-making is fair because the dismantling costs are spread equally over the entire operating period of the facility. (A.C.)

  2. Advanced robotic remote handling system for reactor dismantlement

    International Nuclear Information System (INIS)

    Shinohara, Yoshikuni; Usui, Hozumi; Fujii, Yoshio

    1991-01-01

    An advanced robotic remote handling system equipped with a multi-functional amphibious manipulator has been developed and used to dismantle a portion of radioactive reactor internals of an experimental boiling water reactor in the program of reactor decommissioning technology development carried out by the Japan Atomic Energy Research Institute. (author)

  3. Dismantling Racial and Hegemonic Boundaries for an Inclusive ...

    African Journals Online (AJOL)

    ... expressed experiences of hostile institutional cultures, untransformed curricula that are largely based on European traditions and norms and a general atmosphere that is tilted towards white supremacy. The article also gives specifi c attention to the formation of a unifying organisational culture, requisite for dismantling

  4. Pick-N-Pull Auto Dismantlers, Kansas City, LLC Inc.

    Science.gov (United States)

    The EPA is providing notice of a proposed Administrative Penalty Assessment against Pick-N-Pull Auto Dismantlers, Kansas City, LLC, a subsidiary of Schnitzer Steel Industries, Inc., for alleged violations at its facilities at 8012 East Truman Rd., Kansas C

  5. Dismantling of JPDR begins: to demonstrate advanced technology

    Energy Technology Data Exchange (ETDEWEB)

    1986-12-01

    The first dismantling of the Japan Power Demonstration Reactor (JPDR, BWR, 90 MWt, 12.5 MWe) began on December 4, 1986, claiming the attention of nuclear interests in Japan and overseas. The Japan Atomic Energy Research Institute undertook the project as the second phase of the six year program for dismantling the JPDR at the Tokai Research Establishment. It is the demonstration of the technology developed in the first phase of the program from 1981 to 1986, aiming at establishing a total system for dismantling commercial nuclear power plants in the furture. At the ceremony for the beginning of dismantling held on December 4 at the site, a special switch was operated to fire a gas burner, and cutting of the upper head of the reactor pressure vessel on the service floor of the reactor building began. The long term program on the development and utilization of nuclear energy in 1982 decided the basic policy on reactor decommissioning. Under this policy, in July, 1984, the nuclear subcommittee of the Advisory Committee for Energy set up the guideline for standardized decommissioning suitable to the actual situation in Japan. The schedule of the program, the development of eight fundamental techniques, disassembling techniques, decontamination, measurement and robotics are described. (Kako, I.).

  6. Technicians dismantle the inner section of L3

    CERN Multimedia

    Laurent Guiraud

    2001-01-01

    The technicians are dismantling the forward tracking chamber located at the heart of the L3 detector. This formed part of the hadronic calorimeter, which is used for measuring particle energies. L3 was an experiment at the LEP collider that ran from 1989 to 2000.

  7. Dismantling the silicon microstrip detector on L3

    CERN Multimedia

    Laurent Guiraud

    2001-01-01

    The silicon microstrip detector is located at the heart of the detector and must be kept cool to prevent thermal noise. The work shown here is the removal of the cooling system. L3 was dismantled as part of the closure of the entire LEP accelerator in 2000 to make way for the new LHC.

  8. Chemical Decontamination of Metallic Waste from Uranium Conversion Plant Dismantling

    International Nuclear Information System (INIS)

    Hwang, D. S.; Choi, Y. D.; Hwang, S. T.; Park, J. H.; Byun, J. I.; Jang, N. S.

    2005-01-01

    Korea Atomic Energy Research Institute (KAERI) started a decommissioning program of the uranium conversion plant. Pre-work was carried as follows; installation of the access control facility, installation of a changing room and shower room, designation of an emergency exit way and indicating signs, installation of a radiation management facility, preparation of a storage area for tools and equipments, inspection and load test of crane, distribution and packaging of existing waste, and pre-decontamination of the equipment surface and the interior. First, decommissioning work was performed in kiln room, which will be used for temporary radioactive waste storage room. Kiln room housed hydro fluorination rotary kiln for production of uranium tetra-fluoride. The kiln is about 0.8 m in diameter and 5.5 m long. The total dismantled waste was 6,690 kg, 73 % of which was metallic waste and 27 % the others such as cable, asbestos, concrete, secondary waste, etc. And effluent treatment room and filtration room were dismantled for installation of decontamination equipment and lagoon sludge treatment equipment. There were tanks and square mixer in these rooms. The total dismantled waste was 17,250 kg, 67% of which was metallic waste and 33% the others. These dismantled metallic wastes consist of stainless and carbon steel. In this paper, the stainless steel plate and pipe were decontaminated by the chemical decontamination with ultrasonic

  9. Decontamination and dismantling of large plutonium-contamined glove boxes

    International Nuclear Information System (INIS)

    Draulans, J.

    1991-01-01

    This report describes the work performed in the frame of two C.E.C. - Contracts FI1D-002400-B Decommissioning of very large glove boxes and FI1D-0058 Decommissioning of a complex glove box structure to be dismounted partially on place. Detailed information is given about each glove box. The selection of the solution Transportation of the glove boxes to a specialized dismantling plant is justified. The necessary contacts inside the BELGONUCLEAIRE MOX plant and between the latter and other organizations are explained. The problems of manipulating large gloves are listed and the retained solution of building a so called Stiffening frame around each glove box is described. Furthermore information is given concerning required operators time for cleaning, manipulating, packing and dismantling together with received doses and quantities of waste produced. Concerning the glove box unit partially to be dismounted on place, detailed information is given about the way the glove boxes have been treated prior to this partial dismantling on place and about the way this partial dismantling has been performed. From these results one can conclude that such a delicate task can be performed without major difficulties. Finally information is given of the decontamination test of a highly Pu contaminated glove box with freon with rather poor results and of the preliminary CO 2 blasting tests on non active samples

  10. Dismantling and decommissioning of Jose Cabrera nuclear power plant

    International Nuclear Information System (INIS)

    Rodriguez, A.

    2009-01-01

    With the start of the dismantling works at the Jose Cabrera nuclear power plant now in sight, this is an appropriate moment to look back and consider recent history. The first time that the issue of nuclear power plant dismantling was dealt with was in 1975, at a conference in Paris entitled Nuclear Energy Maturity. Up until then the entire question had been one of design, construction and operation, but since that moment and it has been quite a while since that conference dismantling has begun to be seen as just another activity in the nuclear cycle, a final activity that will sooner or later affect all the facilities, an activity different from its predecessors and with the ultimate objective of restoring the sites for whatever use might be determined. During the 1960s and 1970s, the construction of nuclear power plants was widespread across the entire world. It was the baby boom of nuclear energy and now, forty or fifty years later, we are seeing the arrival of the end of the service lifetime of these plants and are faced with the corresponding general process of dismantling these installations. The dismantling of nuclear power plants has ceased to be an emerging issue and is now consolidated as a regular activity in the nuclear industry, albeit an activity that lacks adequate financing or specific regulation in certain countries. Fortunately this is not the case in Spain, since economic provisions have been planned and the regulatory framework developed. In view of the above, the dismantling of the nuclear power plants is an industrial activity involving specific technologies that implies new professional and business opportunities that should be absorbed and seized by society. In Spain the path followed in this direction has been a long one, as is underlined by the experiences of dismantling the Argos (Barcelona, 1998- 2004) and Arbi (Bilbao, 2002-2005) research reactors, the Andujar Uranium Mill (Jaen, 1991-1995), the Vandellos I nuclear power plant

  11. Waste management concept during dismantling of KKS NPP in Germany

    International Nuclear Information System (INIS)

    Bacmeister, Georg U.

    2008-01-01

    Full text: This paper gives an overview on the waste management of NPP Stade during dismantling. The general idea is to reduce the radioactive waste to about three percentage of the complete dismantling mass. The NPP Stade in Germany was shut down in November 2003. After a transient phase the license for dismantling was given in 2005. In the following 8 years about 20.000 tones of steel and 120.000 tones of concrete will be put out by the dismantling. The yearly output of steel will by about 100 times higher than during the running time of the NNP. For this a new processes for waste management had to be installed. The waste management during dismantling focus on free release (about 97%). Beside some minor exception, the rest is deemed to be radioactive waste. This will be collected in 1000 packages, which are ready to be sent to a final storage. As until now in Germany no final storage is open (and sending of radioactive waste to another country is forbidden), the NNP Stade build an intermediate storage, where the packages may by saved for longest 40 years. The clearance procedure in Germany is regulated in the radiation protection ordinances. It is based on a nuclide specific set of clearance levels. To fulfil these demands the NNP Stade chose a semi automated system for characterization and documentation, which we develop in accordance to our release license. It guaranties a most accurate determination of the relevant nuclides for a set of dismantling material (some 10 to 100 tones). After the characterization only the gamma-activity of the material is measured in boxes of about 500 kg. A short comparison of the chosen procedure with other options, possible in Germany will be given and the decision from the collaboration with the NPP in Barsebaeck, Sweden, will be withdrawn. Beside the free release different options are used for waste management, like incineration, sending to landfill or reuse in nuclear industry. The waste management of the NNP Stade take

  12. Optomechanical proposal for monitoring microtubule mechanical vibrations

    Czech Academy of Sciences Publication Activity Database

    Barzanjeh, Sh.; Salari, V.; Tuszynski, J. A.; Cifra, Michal; Simon, C.

    2017-01-01

    Roč. 96, č. 1 (2017), č. článku 012404. ISSN 2470-0045 R&D Projects: GA ČR(CZ) GA15-17102S Grant - others:AV ČR(CZ) SAV-15-22 Program:Bilaterální spolupráce Institutional support: RVO:67985882 Keywords : Vibrational modes * Microtubule * Resonance frequencies Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 2.366, year: 2016

  13. Emerging microtubule targets in glioma therapy

    Czech Academy of Sciences Publication Activity Database

    Katsetos, C.D.; Reginato, M.J.; Baas, P.W.; D'Agostino, L.; Legido, A.; Tuszynski, J. A.; Dráberová, Eduarda; Dráber, Pavel

    2015-01-01

    Roč. 22, č. 1 (2015), s. 49-72 ISSN 1071-9091 R&D Projects: GA MŠk LH12050; GA MZd NT14467 Grant - others:GA AV ČR M200521203PIPP; NIH(US) R01 NS028785; Philadelphia Health Education Corporation (PHEC)–St. Christopher’s Hospital for Children Reunified Endowment (C.D.K.)(US) 323256 Institutional support: RVO:68378050 Keywords : glioma tumorigenesis * glioblastoma * tubulin * microtubules Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.303, year: 2015

  14. The Japan Power Demonstration Reactor (JPDR) dismantling activities. Dismantling of the reactor enclosure and the auxiliary buildings

    International Nuclear Information System (INIS)

    Seiki, Yoshihiro; Kubo, Takashi.

    1996-01-01

    As the final stage of the JPDR decommissioning program, after the major components were removed from each building of JPDR, the dismantling activities proceeded to the decontamination of contaminated concrete surface and the final radiation survey of buildings. These activities were conducted to verify the developed techniques and the detailed procedures for decontamination, and to allow unrestricted use of the JPDR buildings. Following the decontamination of buildings, the dismantling of each building was started. Before dismantling the buildings, the radiation control designations were changed. The buildings that contaminated embedded pipes were changed from first-class radiation controlled areas to second-class radiation controlled areas. On the other hand, the buildings that had no contaminated pipes were changed to uncontrolled areas. A first-class radiation controlled area allows the use of unsealed sources ; thus, radioactive contamination may exist. A second-class radiation controlled area is one where only sealed sources are allowed. Significant quantities of data and experience were obtained during these activities. The practical procedures for decontamination, the final survey of radioactivity, and the dismantling work of buildings were described in this report. (author)

  15. Microtubules Enable the Planar Cell Polarity of Airway Cilia

    Science.gov (United States)

    Vladar, Eszter K.; Bayly, Roy D.; Sangoram, Ashvin; Scott, Matthew P.; Axelrod, Jeffrey D.

    2012-01-01

    Summary Background Airway cilia must be physically oriented along the longitudinal tissue axis for concerted, directional motility that is essential for proper mucociliary clearance. Results We show that Planar Cell Polarity (PCP) signaling specifies directionality and orients respiratory cilia. Within all airway epithelial cells a conserved set of PCP proteins shows interdependent, asymmetric junctional localization; non-autonomous signaling coordinates polarization between cells; and a polarized microtubule (MT) network is likely required for asymmetric PCP protein localization. We find that basal bodies dock after polarity of PCP proteins is established, are polarized nearly simultaneously, and refinement of basal body/cilium orientation continues during airway epithelial development. Unique to mature multiciliated cells, we identify PCP-regulated, planar polarized MTs that originate from basal bodies and interact, via their plus ends, with membrane domains associated with the PCP proteins Frizzled and Dishevelled. Disruption of MTs leads to misoriented cilia. Conclusions A conserved PCP pathway orients airway cilia by communicating polarity information from asymmetric membrane domains at the apical junctions, through MTs, to orient the MT and actin based network of ciliary basal bodies below the apical surface. PMID:23122850

  16. Quantitative analysis of microtubule orientation in interdigitated leaf pavement cells.

    Science.gov (United States)

    Akita, Kae; Higaki, Takumi; Kutsuna, Natsumaro; Hasezawa, Seiichiro

    2015-01-01

    Leaf pavement cells are shaped like a jigsaw puzzle in most dicotyledon species. Molecular genetic studies have identified several genes required for pavement cells morphogenesis and proposed that microtubules play crucial roles in the interdigitation of pavement cells. In this study, we performed quantitative analysis of cortical microtubule orientation in leaf pavement cells in Arabidopsis thaliana. We captured confocal images of cortical microtubules in cotyledon leaf epidermis expressing GFP-tubulinβ and quantitatively evaluated the microtubule orientations relative to the pavement cell growth axis using original image processing techniques. Our results showed that microtubules kept parallel orientations to the growth axis during pavement cell growth. In addition, we showed that immersion treatment of seed cotyledons in solutions containing tubulin polymerization and depolymerization inhibitors decreased pavement cell complexity. Treatment with oryzalin and colchicine inhibited the symmetric division of guard mother cells.

  17. Data analysis on work activities in dismantling of Japan Power Demonstration Reactor (JPDR). Contract research

    International Nuclear Information System (INIS)

    Shiraishi, Kunio; Sukegawa, Takenori; Yanagihara, Satoshi

    1998-03-01

    The safe dismantling of a retired nuclear power plant was demonstrated by completion of dismantling activities for the Japan Power Demonstration Reactor (JPDR), March, 1996, which had been conducted since 1986. This project was a flag ship project for dismantling of nuclear power plants in Japan, aiming at demonstrating an applicability of developed dismantling techniques in actual dismantling work, developing database on work activities as well as dismantling of components and structures. Various data on dismantling activities were therefore systematically collected and these were accumulated on computer files to build the decommissioning database; dismantling activities were characterized by analyzing the data. The data analysis resulted in producing general forms such as unit activity factors, for example, manpower need per unit weight of component to be dismantled, and simple arithmetic forms for forecasting of project management data to be applied to planning another dismantling project through the evaluation for general use of the analyzed data. The results of data analysis could be usefully applied to planning of future decommissioning of commercial nuclear power plants in Japan. This report describes the data collection and analysis on the JPDR dismantling activities. (author)

  18. Branching microtubule nucleation in Xenopus egg extracts mediated by augmin and TPX2

    Science.gov (United States)

    Petry, Sabine; Groen, Aaron C.; Ishihara, Keisuke; Mitchison, Timothy J.; Vale, Ronald D.

    2013-01-01

    Summary The microtubules that comprise mitotic spindles in animal cells are nucleated at centrosomes and by spindle assembly factors that are activated in the vicinity of chromatin. Indirect evidence also has suggested that microtubules might be nucleated from pre-existing microtubules throughout the spindle, but this process has not been observed directly. Here, we demonstrate microtubule nucleation from the sides of existing microtubules in meiotic Xenopus egg extracts. Daughter microtubules grow at a low branch angle and with the same polarity as mother filaments. Branching microtubule nucleation requires gamma-tubulin and augmin and is stimulated by GTP-bound Ran and its effector TPX2, factors previously implicated in chromatin-stimulated nucleation. Because of the rapid amplification of microtubule numbers and the preservation of microtubule polarity, microtubule-dependent microtubule nucleation is well suited for spindle assembly and maintenance. PMID:23415226

  19. The Drosophila Microtubule-Associated Protein Mars Stabilizes Mitotic Spindles by Crosslinking Microtubules through Its N-Terminal Region

    DEFF Research Database (Denmark)

    Zhang, Gang; Beati, Hamze; Nilsson, Jakob

    2013-01-01

    Correct segregation of genetic material relies on proper assembly and maintenance of the mitotic spindle. How the highly dynamic microtubules (MTs) are maintained in stable mitotic spindles is a key question to be answered. Motor and non-motor microtubule associated proteins (MAPs) have been...

  20. Effects of ultraviolet radiation on microtubule organisation and morphogenesis in plants

    Energy Technology Data Exchange (ETDEWEB)

    Staxen, I.

    1994-09-01

    The involvement of the cytoskeleton in the development of somatic embryos was studied in Larix x eurolepis. Protoplasts were isolated from both somatic embryo-regenerating and non-generating cultures and fractionated on a discontinuous Percoll density gradient. Protoplasts of two cell lines of Larix eurolepis, one with regenerating potential and one lacking this potential, were compared. In contrast to the non-regenerating line were a protoplast-like organisation of the cortical microtubules was maintained, re-organisation of this microtubular network occurred in the regenerable line after only three days of culture, indicating that organised growth was occurring. However, this early organisation of cortical microtubules may not always be a valid marker for regenerable and non-regenerable material. In order to investigate the effect of ultraviolet-B (UV-B, 280-320 nm) radiation on the microtubule cytoskeleton, protoplasts were isolated from leaves of Petunia hybrida and subjected to four different doses of UV-B radiation. The organisation of the microtubules and the progression of the cells through the cell cycle was observed at 0, 24, 48 and 72 h after irradiation. UV-B induced breaks in the cortical microtubules resulting in shorter fragments with increasing amounts of radiation. Also, the division of the protoplasts was delayed. Whole Petunia plants were grown in growth chambers in the presence and absence of UV-B. The plants responded to UV-B with increased rates of CO{sub 2} assimilation, a 60% increase in UV-screening compounds and the changes in the morphology of the leaves that were reflected in a 70-100% increase in leaf area and 20% decrease in leaf thickness. The microtubules of the epidermal cells was not affected by UV-B, nor was the number of epidermal cells (per unit area). The increase in leaf area in the UV-treated plants appeared due to stimulation of cell division in the leaf meristems. 111 refs, 5 figs, 2 tabs.

  1. LEP Dismantling - a first Step into New Era

    CERN Multimedia

    2000-01-01

    The aim of the project is to remove the LEP machine and most of the services from the underground areas in order to install the LHC within the time constraints of its civil engineering and installation programmes The dismantling of LEP will be the first project to be executed under the new INB (Installation Nucléaire de Base) convention for the LHC. This talk will give an overview of the LEP Dismantling project covering traceability, planning, infrastructure and execution. It will explain what it means for our accelerators to be classified as INB's and will introduce the changes in working and safety procedures, which will be enforced from the beginning of October. Note: The presentation will be made in French with the transparencies in English.

  2. Long range manipulator development and experiments with dismantling tools

    International Nuclear Information System (INIS)

    Mueller, K.

    1993-01-01

    An existing handling system (EMIR) was used as a carrier system for various tools for concrete dismantling and radiation protection monitoring. It combined the advantages of long reach and high payload with highly dexterous kinematics. This system was enhanced mechanically to allow the use of different tools. Tool attachment devices for automatic tool exchange were investigated as well as interfaces (electric, hydraulic, compressed air, cooling water and signals). The control system was improved with regard to accuracy and sensor data processing. Programmable logic controller functions for tool control were incorporated. A free field mockup of the EMIR was build that allowed close simulation of dismantling scenarios without radioactive inventory. Aged concrete was provided for the integration tests. The development scheduled included the basic concept investigation; the development of tools and sensors; the EMIR hardware enhancement including a tool exchange; the adaption of tools and mockup and the final evaluation of the system during experiments

  3. Towards a more professional demolition and dismantling industry

    International Nuclear Information System (INIS)

    1988-01-01

    The work of the National Economic Development Office Demolition and Dismantling Group in four areas which are crucial to the economic performance of the demolition and dismantling industry and its safety record is considered. The first concerns the availability and accessibility of information about unconventional structures and details are given of the sort of information often kept for different types of structure. Secondly, the need is stressed for guidelines for the client, particularly on the risks involved and the choice of a competent contractor. Thirdly, basic credentials which it is important for contractors to set out in order to establish a good reputation for the industry are set out. Finally, the particular case of nuclear power station decommissioning is considered with reference to the size of the market, the pioneering knowledge to be gained from the decommissioning of the Windscale Advanced Gas-cooled Reactor, private sector involvement and the special techniques required. (U.K.)

  4. Multiscale modeling and simulation of microtubule-motor-protein assemblies

    Science.gov (United States)

    Gao, Tong; Blackwell, Robert; Glaser, Matthew A.; Betterton, M. D.; Shelley, Michael J.

    2015-12-01

    Microtubules and motor proteins self-organize into biologically important assemblies including the mitotic spindle and the centrosomal microtubule array. Outside of cells, microtubule-motor mixtures can form novel active liquid-crystalline materials driven out of equilibrium by adenosine triphosphate-consuming motor proteins. Microscopic motor activity causes polarity-dependent interactions between motor proteins and microtubules, but how these interactions yield larger-scale dynamical behavior such as complex flows and defect dynamics is not well understood. We develop a multiscale theory for microtubule-motor systems in which Brownian dynamics simulations of polar microtubules driven by motors are used to study microscopic organization and stresses created by motor-mediated microtubule interactions. We identify polarity-sorting and crosslink tether relaxation as two polar-specific sources of active destabilizing stress. We then develop a continuum Doi-Onsager model that captures polarity sorting and the hydrodynamic flows generated by these polar-specific active stresses. In simulations of active nematic flows on immersed surfaces, the active stresses drive turbulent flow dynamics and continuous generation and annihilation of disclination defects. The dynamics follow from two instabilities, and accounting for the immersed nature of the experiment yields unambiguous characteristic length and time scales. When turning off the hydrodynamics in the Doi-Onsager model, we capture formation of polar lanes as observed in the Brownian dynamics simulation.

  5. Nonlinear dynamics of C-terminal tails in cellular microtubules

    Science.gov (United States)

    Sekulic, Dalibor L.; Sataric, Bogdan M.; Zdravkovic, Slobodan; Bugay, Aleksandr N.; Sataric, Miljko V.

    2016-07-01

    The mechanical and electrical properties, and information processing capabilities of microtubules are the permanent subject of interest for carrying out experiments in vitro and in silico, as well as for theoretical attempts to elucidate the underlying processes. In this paper, we developed a new model of the mechano-electrical waves elicited in the rows of very flexible C-terminal tails which decorate the outer surface of each microtubule. The fact that C-terminal tails play very diverse roles in many cellular functions, such as recruitment of motor proteins and microtubule-associated proteins, motivated us to consider their collective dynamics as the source of localized waves aimed for communication between microtubule and associated proteins. Our approach is based on the ferroelectric liquid crystal model and it leads to the effective asymmetric double-well potential which brings about the conditions for the appearance of kink-waves conducted by intrinsic electric fields embedded in microtubules. These kinks can serve as the signals for control and regulation of intracellular traffic along microtubules performed by processive motions of motor proteins, primarly from kinesin and dynein families. On the other hand, they can be precursors for initiation of dynamical instability of microtubules by recruiting the proper proteins responsible for the depolymerization process.

  6. Multiscale modeling and simulation of microtubule-motor-protein assemblies.

    Science.gov (United States)

    Gao, Tong; Blackwell, Robert; Glaser, Matthew A; Betterton, M D; Shelley, Michael J

    2015-01-01

    Microtubules and motor proteins self-organize into biologically important assemblies including the mitotic spindle and the centrosomal microtubule array. Outside of cells, microtubule-motor mixtures can form novel active liquid-crystalline materials driven out of equilibrium by adenosine triphosphate-consuming motor proteins. Microscopic motor activity causes polarity-dependent interactions between motor proteins and microtubules, but how these interactions yield larger-scale dynamical behavior such as complex flows and defect dynamics is not well understood. We develop a multiscale theory for microtubule-motor systems in which Brownian dynamics simulations of polar microtubules driven by motors are used to study microscopic organization and stresses created by motor-mediated microtubule interactions. We identify polarity-sorting and crosslink tether relaxation as two polar-specific sources of active destabilizing stress. We then develop a continuum Doi-Onsager model that captures polarity sorting and the hydrodynamic flows generated by these polar-specific active stresses. In simulations of active nematic flows on immersed surfaces, the active stresses drive turbulent flow dynamics and continuous generation and annihilation of disclination defects. The dynamics follow from two instabilities, and accounting for the immersed nature of the experiment yields unambiguous characteristic length and time scales. When turning off the hydrodynamics in the Doi-Onsager model, we capture formation of polar lanes as observed in the Brownian dynamics simulation.

  7. Process Concepts for Semi-automatic Dismantling of LCD Televisions

    OpenAIRE

    Elo, Kristofer; Sundin, Erik

    2014-01-01

    There is a large variety of electrical and electronic equipment products, for example liquid crystal display television sets (LCD TVs), in the waste stream today. Many LCD TVs contain mercury, which is a challenge to treat at the recycling plants. Two current used processes to recycle LCD TVs are automated shredding and manual disassembly. This paper aims to present concepts for semi-automated dismantling processes for LCD TVs in order to achieve higher productivity and flexibility, and in tu...

  8. Development of a handling technology for underwater inspection and dismantling

    International Nuclear Information System (INIS)

    Rose, N.

    1994-01-01

    For the purpose of underwater inspection and dismantling of nuclear facilities, a prototype of a freely submersible, remote-controlled handling system was developed and tested under laboratory conditions. Particular interest was taken in the specific boundary conditions of the area of application and the methodological concept. The system was developed in three phases; in each phase, a prototype was constructed and tested. (orig.) [de

  9. Decontamination and dismantlement of Plant 7 at Fernald

    International Nuclear Information System (INIS)

    Albertin, M.; Borgman, T.; Zebick, B.

    1994-01-01

    Decontamination and dismantlement (D ampersand D) tasks have been successfully completed on Plant 7 at the Fernald Environmental Management Project. The seven story facility was radiologically, chemically, and biologically contaminated. The work involved the D ampersand D work beginning with safe shutdown and gross decontamination, and ended with removal of the structural steel. A series of lessons learned were gained which include use of explosives, bidding tactics, safe shutdown, building decontamination and lockdown, use of seam climbers, etc

  10. Dismantling of the rooms 82 to 100 at Marcoule

    International Nuclear Information System (INIS)

    Fiol, A.

    1988-01-01

    The dismantling of the rooms 82 to 100 at Marcoule is up to now, the most important decommissioning operation. The COGEMA Marcoule had the responsibility of studying and organizing the operation. On the works site the work was performed by STMI. The construction of a complete nuclear waste processing system was necessary, to protect against Pu contamination. Moreover, the efficiency of the work, was improved by the development and use of large special cutting tools [fr

  11. Structural insights into microtubule doublet interactions inaxonemes

    Energy Technology Data Exchange (ETDEWEB)

    Downing, Kenneth H.; Sui, Haixin

    2007-06-06

    Coordinated sliding of microtubule doublets, driven by dynein motors, produces periodic beating of the axoneme. Recent structural studies of the axoneme have used cryo-electron tomography to reveal new details of the interactions among some of the multitude of proteins that form the axoneme and regulate its movement. Connections among the several sets of dyneins, in particular, suggest ways in which their actions may be coordinated. Study of the molecular architecture of isolated doublets has provided a structural basis for understanding the doublet's mechanical properties that are related to the bending of the axoneme, and has also offered insight into its potential role in the mechanism of dynein activity regulation.

  12. Contaminated Metal Components in Dismantling by Hot Cutting Processes

    International Nuclear Information System (INIS)

    Cesari, Franco G.; Conforti, Gianmario; Rogante, Massimo; Giostri, Angelo

    2006-01-01

    During the preparatory dismantling activities of Caorso's Nuclear Power Plant (NPP), an experimental campaign using plasma and oxyacetylene metal cutting processes has been performed and applied to plates and tubes exposed to the coolant steam of the reactor. The plant (Boiling Water Reactor, 870 MWe) was designed and built in the 70's, and it was fully operating by 1981 to 1986 being shut down after 1987 Italy's poll that abrogated nuclear power based on U235 fission. The campaign concerns no activated materials, even if the analyses have been performed of by use contaminated components under the free release level, not yet taking into account radioactivity. In this paper, the parameters related to inhalable aerosol, solid and volatile residuals production have been, studied during hot processes which applies the same characteristics of the cutting in field for the dismantling programs of Caorso NPP. The technical parameters such as cutting time and cutting rate vs. pipe diameter/thickness/schedule or plate thickness for ferritic alloys and the emissions composition coming from the sectioning are also reported. The results underline the sort of trouble that can emerge in the cutting processes, in particular focusing on the effects comparison between the two cutting processes and the chemical composition of powders captured by filtering the gaseous emission. Some preliminary considerations on methodology to be used during the dismantling have been presented. (authors)

  13. Dismantling of the 50 MW steam generator test facility

    International Nuclear Information System (INIS)

    Nakai, S.; Onojima, T.; Yamamoto, S.; Akai, M.; Isozaki, T.; Gunji, M.; Yatabe, T.

    1997-01-01

    We have been dismantling the 50MW Steam Generator Test Facility (50MWSGTF). The objectives of the dismantling are reuse of sodium components to a planned large scale thermal hydraulics sodium test facility and the material examination of component that have been operated for long time in sodium. The facility consisted of primary sodium loop with sodium heater by gas burner as heat source instead of reactor, secondary sodium loop with auxiliary cooling system (ACS) and water/steam system with steam temperature and pressure reducer instead of turbine. It simulated the 1 loop of the Monju cooling system. The rated power of the facility was 50MWt and it was about 1/5 of the Monju power plant. Several sodium removal methods are applied. As for the components to be dismantled such as piping, intermediate heat exchanger (IHX), air cooled heat exchangers (AC), sodium is removed by steam with nitrogen gas in the air or sodium is burned in the air. As for steam generators which material tests are planned, sodium is removed by steam injection with nitrogen gas to the steam generator. The steam generator vessel is filled with nitrogen and no air in the steam generator during sodium removal. As for sodium pumps, pump internal structure is pulled out from the casing and installed into the tank. After the installation, sodium is removed by the same method of steam generator. As for relatively small reuse components such as sodium valves, electromagnet flow meters (EMFs) etc., sodium is removed by alcohol process. (author)

  14. Dismantlement and destruction of chemical, nuclear and conventional weapons

    International Nuclear Information System (INIS)

    Schulte, N.T.

    1997-01-01

    The safe destruction and dismantling of chemical, nuclear and conventional weapons is of fundamental importance to the security of all countries represented in this volume. Expertise in the field is not confined to one country or organisation: all can benefit from each other. There is an ever present danger of proliferation of weapons of mass destruction: approximately two dozen countries have ongoing programmes to develop or acquire such weapons, and many are also gaining the capability to build air-surface delivery systems. But much can be done to prevent proliferation by reducing leakage of materials and know-how and by solving the problems of the destruction of surplus weapons systems, which has now come to be a key issue. In 13 sessions of the workshop attention was paid to (1) Dismantlement and Destruction of Chemical, Nuclear and Conventional Weapons; (2) Status of Implementation of Arms Control Treaties and Voluntary Commitments; (3) National Perspectives on Cooperation in Disarmament; (4) Stocktaking of National and Bilateral Disposal/Destruction Programmes: Chemical Weapons; (5) Stocktaking of National and Bilateral Disposal/Destruction Programmes: Nuclear Weapons; (6) Stocktaking of National and Bilateral Disposal/Destruction Programmes: Conventional Weapons. Session; (7) Experience with Currently Employed Chemical Destruction Technologies; (8) Alternative Chemical Destruction Technologies; (9) Deactivation, Dismantlement and Destruction of Delivery Systems and Infrastructure for Nuclear Weapons; (10) Storage, Safeguarding and Disposition of Fissile Materials; (11) Technologies for Conversion and Civil Use of Demilitarized Materials; (12) International Organizations; and (13) Environmental Challenges Posed by Chemical and Nuclear Disarmament

  15. A Study on Dismantling and Verifying North Korea's Nuclear Capabilities

    International Nuclear Information System (INIS)

    Kim, Young Jae; Cheon, Seong Whun

    2007-10-01

    North Korea's nuclear weapon development is a serious threat to South Korea's national security and can become a trigger to change the status quo in the Korean peninsula. Having prevailed security dynamics in Northeast Asia last 20 years, the North Korea's nuclear problem faced a key turning point when Pyongyang tested its first nuclear weapon on October 9, 2006. Despite this test, however, diplomatic efforts to resolve the nuclear issue were never given up, resulting in a so-called, initial agreement signed at the Six-Party Talks in February 2007. With the Six-Party Talks being held more than four years, the six countries have had sufficient time to discuss principal and political matters regarding the dismantlement of North Korea's nuclear weapons. Under the circumstances, this report is going to study practical and detail issues related with dismantling the North's nuclear weapons. Specifically, in light of historical experiences, the report will investigate possible problems to be faced in the course of dismantlement and propose policy measures to overcome these problems

  16. Dismantling and decontamination of Piver prototype vitrification plant

    International Nuclear Information System (INIS)

    Jouan, A.; Roudil, S.; Thomas, F.

    1991-01-01

    The PIVER prototype was targeted for dismantling in order to install a new pilot facility for the french continuous vitrification process. Most of the work involved the vitrification cell containing the process equipments, which had to be cleared out and thoroughly decontaminated; this implied disassembling, cutting up, conditioning and removing all the equipment installed in the cell. Remote manipulation, handling and cutting devices were used and some prior modifications were implemented in the cell environment. The dismantling procedure was conducted under a detailed programme defining the methodology for each operation. After equipment items and active zones were identified, the waste materials were removed, and several liquid decontamination operations were implemented. Removed activity, levels of irradiation in the cell and doses integrated by personnel were monitored to control progress and to adapt procedures to the conditions encountered. At the end of December 1989, the PIVER cleanup programme was at 87% complete and the total activity removed was 2.11 X 10 14 Bq (5712 Ci). The objective now is to obtain suitable working conditions in order to allow operators to enter the cell to remove items that are inaccessible or which cannot be dismantled by remote manipulators and to complete the decontamination procedure

  17. Identification of interphase functions for the NIMA kinase involving microtubules and the ESCRT pathway.

    Directory of Open Access Journals (Sweden)

    Meera Govindaraghavan

    2014-03-01

    Full Text Available The Never in Mitosis A (NIMA kinase (the founding member of the Nek family of kinases has been considered a mitotic specific kinase with nuclear restricted roles in the model fungus Aspergillus nidulans. By extending to A. nidulans the results of a synthetic lethal screen performed in Saccharomyces cerevisiae using the NIMA ortholog KIN3, we identified a conserved genetic interaction between nimA and genes encoding proteins of the Endosomal Sorting Complex Required for Transport (ESCRT pathway. Absence of ESCRT pathway functions in combination with partial NIMA function causes enhanced cell growth defects, including an inability to maintain a single polarized dominant cell tip. These genetic insights suggest NIMA potentially has interphase functions in addition to its established mitotic functions at nuclei. We therefore generated endogenously GFP-tagged NIMA (NIMA-GFP which was fully functional to follow its interphase locations using live cell spinning disc 4D confocal microscopy. During interphase some NIMA-GFP locates to the tips of rapidly growing cells and, when expressed ectopically, also locates to the tips of cytoplasmic microtubules, suggestive of non-nuclear interphase functions. In support of this, perturbation of NIMA function either by ectopic overexpression or through partial inactivation results in marked cell tip growth defects with excess NIMA-GFP promoting multiple growing cell tips. Ectopic NIMA-GFP was found to locate to the plus ends of microtubules in an EB1 dependent manner, while impairing NIMA function altered the dynamic localization of EB1 and the cytoplasmic microtubule network. Together, our genetic and cell biological analyses reveal novel non-nuclear interphase functions for NIMA involving microtubules and the ESCRT pathway for normal polarized fungal cell tip growth. These insights extend the roles of NIMA both spatially and temporally and indicate that this conserved protein kinase could help integrate cell

  18. Birefringence of single and bundled microtubules.

    Science.gov (United States)

    Oldenbourg, R; Salmon, E D; Tran, P T

    1998-01-01

    We have measured the birefringence of microtubules (MTs) and of MT-based macromolecular assemblies in vitro and in living cells by using the new Pol-Scope. A single microtubule in aqueous suspension and imaged with a numerical aperture of 1.4 had a peak retardance of 0.07 nm. The peak retardance of a small bundle increased linearly with the number of MTs in the bundle. Axonemes (prepared from sea urchin sperm) had a peak retardance 20 times higher than that of single MTs, in accordance with the nine doublets and two singlets arrangement of parallel MTs in the axoneme. Measured filament retardance decreased when the filament was defocused or the numerical aperture of the imaging system was decreased. However, the retardance "area," which we defined as the image retardance integrated along a line perpendicular to the filament axis, proved to be independent of focus and of numerical aperture. These results are in good agreement with a theory that we developed for measuring retardances with imaging optics. Our theoretical concept is based on Wiener's theory of mixed dielectrics, which is well established for nonimaging applications. We extend its use to imaging systems by considering the coherence region defined by the optical set-up. Light scattered from within that region interferes coherently in the image point. The presence of a filament in the coherence region leads to a polarization dependent scattering cross section and to a finite retardance measured in the image point. Similar to resolution measurements, the linear dimension of the coherence region for retardance measurements is on the order lambda/(2 NA), where lambda is the wavelength of light and NA is the numerical aperture of the illumination and imaging lenses.

  19. Development of decommissioning engineering support system for fugen. Development of support system during actual dismantlement works

    International Nuclear Information System (INIS)

    Masanori Izumi; Yukihiro Iguchi; Yoshiki Kannehira

    2005-01-01

    The Advanced Thermal Reactor, Fugen Nuclear Power Station was permanently shut down in March 2003, and is now preparing for decommissioning. We have been developing Decommissioning Engineering Support System (DEXUS) aimed at planning optimal dismantlement process and carrying out dismantlement work safely and precisely. DEXUS consists of 'decommissioning planning support system' and 'dismantling support system'. The dismantling support system is developed aiming at using during actual dismantling work. It consists of three subsystems such as 'Worksite Visualization System', 'Dismantling Data Collection System' and 'Generated Waste Management System'. 'Worksite Visualization System' is a support system designed to provide the necessary information to workers during actual dismantlement works. And this system adopts AR (Augmented Reality) technology, overlapping calculation information into real world. 'Dismantling Data Collection System' is to collect necessary data for improving accuracy of decommissioning planning by evaluating work content and worker equipage, work time for dismantlement works. 'Generated Waste Management system' is a system recording necessary information by attaching the barcode to dismantled wastes or the containers. We can get the information of generated waste by recording generation place, generated time, treatment method and the contents. These subsystems enable to carry out reasonable and safe decommissioning of Fugen. In addition, we expect that those systems will be used for decommissioning of other nuclear facilities in the future. (authors)

  20. Aging Studies of VCE Dismantlement Returns

    Energy Technology Data Exchange (ETDEWEB)

    Letant, S; Alviso, C; Pearson, M; Albo, R; Small, W; Wilson, T; Chinn, S; Maxwell, R

    2011-10-17

    VCE is an ethylene/vinyl acetate/vinyl alcohol terpolymer binder for filled elastomers which is designed to accept high filler loadings. Filled elastomer parts consist of the binder (VCE), a curing agent (Hylene MP, diphenol-4-4{prime}-methylenebis(phenylcarbamate)), a processing aid (LS, lithium stearate), and filler particles (typically 70% fraction by weight). The curing of the filled elastomer parts occurs from the heat-activated reaction between the hydroxyl groups of VCE with the Hylene MP curing agent, resulting in a cross-linked network. The final vinyl acetate content is typically between 34.9 and 37.9%, while the vinyl alcohol content is typically between 1.27 and 1.78%. Surveillance data for this material is both scarce and scattered, complicating the assessment of any aging trends in systems. In addition, most of the initial surveillance efforts focused on mechanical properties such as hardness and tensile strength, and chemical information is therefore lacking. Material characterization and aging studies had been performed on previous formulations of the VCE material but the Ethylene Vinyl Acetate (EVA) starting copolymer is no longer commercially available. New formulations with replacement EVA materials are currently being established and will require characterization as well as updated aging models.

  1. Effects of the KIF2C neck peptide on microtubules: lateral disintegration of microtubules and β-structure formation.

    Science.gov (United States)

    Shimizu, Youské; Shimizu, Takashi; Nara, Masayuki; Kikumoto, Mahito; Kojima, Hiroaki; Morii, Hisayuki

    2013-04-01

    Members of the kinesin-13 sub-family, including KIF2C, depolymerize microtubules. The positive charge-rich 'neck' region extending from the N-terminus of the catalytic head is considered to be important in the depolymerization activity. Chemically synthesized peptides, covering the basic region (A182-E200), induced a sigmoidal increase in the turbidity of a microtubule suspension. The increase was suppressed by salt addition or by reduction of basicity by amino acid substitutions. Electron microscopic observations revealed ring structures surrounding the microtubules at high peptide concentrations. Using the peptide A182-D218, we also detected free thin straight filaments, probably protofilaments disintegrated from microtubules. Therefore, the neck region, even without the catalytic head domain, may induce lateral disintegration of microtubules. With microtubules lacking anion-rich C-termini as a result of subtilisin treatment, addition of the peptide induced only a moderate increase in turbidity, and rings and protofilaments were rarely detected, while aggregations, also thought to be caused by lateral disintegration, were often observed in electron micrographs. Thus, the C-termini are not crucial for the action of the peptides in lateral disintegration but contribute to structural stabilization of the protofilaments. Previous structural studies indicated that the neck region of KIF2C is flexible, but our IR analysis suggests that the cation-rich region (K190-A204) forms β-structure in the presence of microtubules, which may be of significance with regard to the action of the neck region. Therefore, the neck region of KIF2C is sufficient to cause disintegration of microtubules into protofilaments, and this may contribute to the ability of KIF2C to cause depolymerization of microtubules. © 2013 The Authors Journal compilation © 2013 FEBS.

  2. Lysosomes are associated with microtubules and not with intermediate filaments in cultured fibroblasts.

    OpenAIRE

    Collot, M; Louvard, D; Singer, S J

    1984-01-01

    Double immunofluorescent labeling experiments for lysosomes and either microtubules or vimentin intermediate filaments in cultured well-spread fibroblasts show a remarkable degree of superposition of the lysosomes and the microtubules. Under two different sets of conditions where the microtubules and intermediate filaments are well segregated from one another, the lysosomes remain codistributed with the microtubules. It is suggested that this specific association of lysosomes with microtubule...

  3. Towards the creation of an industrial sector dedicated to nuclear dismantling

    International Nuclear Information System (INIS)

    Anon.

    2015-01-01

    In next decades the business of nuclear dismantling is expected to grow exponentially due to the decommissioning of nuclear facilities that will have reached the end of their operating life. Dismantling has 2 main features: dismantling operations on a same site can span decades and dismantling is a new activity in which innovations are likely to appear and may benefit other sectors. In France regional authorities have promoted public-private partnerships in order to make working together small enterprises very specialized in sectors like robotic, laser cutting, waste processing, remote operations... with public laboratories dedicated to nuclear research, and with graduate schools to include dismantling in curriculum and with major industrial operators of the nuclear industry. The aim is the creation of jobs and the building of an industrial sector able to win market shares in the worldwide business of nuclear dismantling. (A.C.)

  4. and its allicin on microtubule and cancer cell lines

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-05

    Oct 5, 2009 ... microtubule protein polymer that treated by A. hirtifolium. (A), and allicin (B) in .... with a chromogenic thiol: reaction of 4-mercaptopyridine with ... transformed tumor growth in vivo by diallyl disulfide is associated with inhibition ...

  5. EML proteins in microtubule regulation and human disease.

    Science.gov (United States)

    Fry, Andrew M; O'Regan, Laura; Montgomery, Jessica; Adib, Rozita; Bayliss, Richard

    2016-10-15

    The EMLs are a conserved family of microtubule-associated proteins (MAPs). The founding member was discovered in sea urchins as a 77-kDa polypeptide that co-purified with microtubules. This protein, termed EMAP for echinoderm MAP, was the major non-tubulin component present in purified microtubule preparations made from unfertilized sea urchin eggs [J. Cell Sci. (1993) 104: , 445-450; J. Cell Sci. (1987) 87: (Pt 1), 71-84]. Orthologues of EMAP were subsequently identified in other echinoderms, such as starfish and sand dollar, and then in more distant eukaryotes, including flies, worms and vertebrates, where the name of ELP or EML (both for EMAP-like protein) has been adopted [BMC Dev. Biol. (2008) 8: , 110; Dev. Genes Evol. (2000) 210: , 2-10]. The common property of these proteins is their ability to decorate microtubules. However, whether they are associated with particular microtubule populations or exercise specific functions in different microtubule-dependent processes remains unknown. Furthermore, although there is limited evidence that they regulate microtubule dynamics, the biochemical mechanisms of their molecular activity have yet to be explored. Nevertheless, interest in these proteins has grown substantially because of the identification of EML mutations in neuronal disorders and oncogenic fusions in human cancers. Here, we summarize our current knowledge of the expression, localization and structure of what is proving to be an interesting and important class of MAPs. We also speculate about their function in microtubule regulation and highlight how the studies of EMLs in human diseases may open up novel avenues for patient therapy. © 2016 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  6. Optical properties of template synthesized nanowalled ZnS microtubules

    Science.gov (United States)

    Kumar, Rajesh; Chakarvarti, S. K.

    2007-12-01

    Electrodeposition is a versatile technique combining low processing cost with ambient conditions that can be used to prepare metallic, polymeric and semiconducting nano/micro structures. In the present work, track-etch membranes (TEMs) of makrofol (KG) have been used as templates for synthesis of ZnS nanowalled microtubules using electrodeposition technique. The morphology of the microtubules was characterized by scanning electron microscopy. Size effects on the band gap of tubules have also been studied by UV-visible spectrophotometer.

  7. Analysis of dismantling possibility and unloading efforts of fuel assemblies from core of WWER

    International Nuclear Information System (INIS)

    Danilov, V.; Dobrov, V.; Semishkin, V.; Vasilchenko, I.

    2006-01-01

    The computation methods of optimal dismantling sequence of fuel assemblies (FA) from core of WWER after different operating periods and accident conditions are considered. The algorithms of fuel dismantling sequence are constructed both on the basis of analysis of mutual spacer grid overlaps of adjacent fuel assemblies and numerical structure analysis of efforts required for FA removal as FA heaving from the core. Computation results for core dismantling sequence after 3-year operating period and LB LOCA are presented in the paper

  8. Nonlinear dynamics of C–terminal tails in cellular microtubules

    Energy Technology Data Exchange (ETDEWEB)

    Sekulic, Dalibor L., E-mail: dalsek@uns.ac.rs; Sataric, Bogdan M.; Sataric, Miljko V. [University of Novi Sad, Faculty of Technical Sciences, Novi Sad (Serbia); Zdravkovic, Slobodan [University of Belgrade, Institute of Nuclear Sciences Vinca, Belgrade (Serbia); Bugay, Aleksandr N. [Laboratory of Radiation Biology, Joint Institute for Nuclear Research, Dubna (Russian Federation)

    2016-07-15

    The mechanical and electrical properties, and information processing capabilities of microtubules are the permanent subject of interest for carrying out experiments in vitro and in silico, as well as for theoretical attempts to elucidate the underlying processes. In this paper, we developed a new model of the mechano–electrical waves elicited in the rows of very flexible C–terminal tails which decorate the outer surface of each microtubule. The fact that C–terminal tails play very diverse roles in many cellular functions, such as recruitment of motor proteins and microtubule–associated proteins, motivated us to consider their collective dynamics as the source of localized waves aimed for communication between microtubule and associated proteins. Our approach is based on the ferroelectric liquid crystal model and it leads to the effective asymmetric double-well potential which brings about the conditions for the appearance of kink–waves conducted by intrinsic electric fields embedded in microtubules. These kinks can serve as the signals for control and regulation of intracellular traffic along microtubules performed by processive motions of motor proteins, primarly from kinesin and dynein families. On the other hand, they can be precursors for initiation of dynamical instability of microtubules by recruiting the proper proteins responsible for the depolymerization process.

  9. Nonlinear dynamics of C–terminal tails in cellular microtubules

    International Nuclear Information System (INIS)

    Sekulic, Dalibor L.; Sataric, Bogdan M.; Sataric, Miljko V.; Zdravkovic, Slobodan; Bugay, Aleksandr N.

    2016-01-01

    The mechanical and electrical properties, and information processing capabilities of microtubules are the permanent subject of interest for carrying out experiments in vitro and in silico, as well as for theoretical attempts to elucidate the underlying processes. In this paper, we developed a new model of the mechano–electrical waves elicited in the rows of very flexible C–terminal tails which decorate the outer surface of each microtubule. The fact that C–terminal tails play very diverse roles in many cellular functions, such as recruitment of motor proteins and microtubule–associated proteins, motivated us to consider their collective dynamics as the source of localized waves aimed for communication between microtubule and associated proteins. Our approach is based on the ferroelectric liquid crystal model and it leads to the effective asymmetric double-well potential which brings about the conditions for the appearance of kink–waves conducted by intrinsic electric fields embedded in microtubules. These kinks can serve as the signals for control and regulation of intracellular traffic along microtubules performed by processive motions of motor proteins, primarly from kinesin and dynein families. On the other hand, they can be precursors for initiation of dynamical instability of microtubules by recruiting the proper proteins responsible for the depolymerization process.

  10. Ibuprofen regulation of microtubule dynamics in cystic fibrosis epithelial cells.

    Science.gov (United States)

    Rymut, Sharon M; Kampman, Claire M; Corey, Deborah A; Endres, Tori; Cotton, Calvin U; Kelley, Thomas J

    2016-08-01

    High-dose ibuprofen, an effective anti-inflammatory therapy for the treatment of cystic fibrosis (CF), has been shown to preserve lung function in a pediatric population. Despite its efficacy, few patients receive ibuprofen treatment due to potential renal and gastrointestinal toxicity. The mechanism of ibuprofen efficacy is also unclear. We have previously demonstrated that CF microtubules are slower to reform after depolymerization compared with respective wild-type controls. Slower microtubule dynamics in CF cells are responsible for impaired intracellular transport and are related to inflammatory signaling. Here, it is identified that high-dose ibuprofen treatment in both CF cell models and primary CF nasal epithelial cells restores microtubule reformation rates to wild-type levels, as well as induce extension of microtubules to the cell periphery. Ibuprofen treatment also restores microtubule-dependent intracellular transport monitored by measuring intracellular cholesterol transport. These effects are specific to ibuprofen as other cyclooxygenase inhibitors have no effect on these measures. Effects of ibuprofen are mimicked by stimulation of AMPK and blocked by the AMPK inhibitor compound C. We conclude that high-dose ibuprofen treatment enhances microtubule formation in CF cells likely through an AMPK-related pathway. These findings define a potential mechanism to explain the efficacy of ibuprofen therapy in CF. Copyright © 2016 the American Physiological Society.

  11. Status of the Digital Mock-up System for the dismantling of the nuclear facilities

    International Nuclear Information System (INIS)

    Park, Hee Seoung; Kim, S. K.; Lee, K. W.; Oh, W. J.

    2004-12-01

    The database system have already developed is impossible to solve a quantitative evaluation about a various situation from the dismantle activities of the reactor had contaminated with radioactivity. To satisfy the requirements for safety and economical efficiency among a major decommissioning technologies, it need a system that can evaluate and estimate dismantling scheduling, amount of radioactive waste being dismantled, and decommissioning cost. We have review and analyzed status of the digital mock-up system to get a technical guide because we have no experience establishment of one relation to dismantling of research reactor and nuclear power plant

  12. User Interface Technology to Reduce Mental Transformations for Tangible Remote Dismantling Simulator

    Energy Technology Data Exchange (ETDEWEB)

    Hyun, Dongjun; Kim, Ikjune; Lee, Jonghwan; Kim, Geun-Ho; Jeong, Kwan-Seong; Choi, Byung-Seon; Moon, Jeikwon; Choi, Jong-Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    High-level radiation of the major components restricts access by human workers, and makes an accident or outage during the dismantling process more difficult to deal with. Since unexpected situations causes waste of budget and an aggravation of safety, the preliminary verification of the dismantling processes and equipment by the tangible remote dismantling simulator is very important. The design optimization of the dismantling processes and equipment is one of the most important objectives of the tangible remote dismantling simulator, as well. This paper proposes a user interface technology to reduce mental transformations for the tangible remote dismantling simulator. At the dismantling process simulation using the tangible remote dismantling simulator, the most difficult work is the remote operation handling the high degrees-of-freedom (DOF) manipulator due to complex mental transformations. The proposed user interface technology reduces mental transformations with constraints using the point projection and direction projection. The test result of the cutting process over the closure head of the RPV demonstrates that the proposed mental transformation reduction technology is operated successfully in the tangible remote dismantling simulator, and lets the operator be easy to control the high DOF manipulator even in the most difficult operation by reducing DOFs to be controlled manually.

  13. Development of project management data calculation models relating to dismantling of nuclear facilities. Contract research

    Energy Technology Data Exchange (ETDEWEB)

    Sukegawa, Takenori; Ohshima, Soichiro; Shiraishi, Kunio; Yanagihara, Satoshi [Department of Decommissioning and Waste Management, Tokai Research Establishment, Japan Atomic Energy Research Institute, Tokai Ibaraki (Japan)

    1999-02-01

    Labor-hours necessary for dismantling activities are generally estimated based on experience, for example, as a form of unit productivity factors such as the relationship between labor-hours and weight of components dismantled which were obtained by actual dismantling activities. The project management data calculation models together with unit productivity factors for basic dismantling work activities were developed by analyzing the data obtained from the Japan Power Demonstration Reactor (JPDR) dismantling project, which will be applicable to estimation of labor-hours in various dismantling conditions. Typical work breakdown structures were also prepared by categorizing repeatable basic dismantling work activities for effective planning of dismantling activities. The labor-hours for dismantling the JPDR components and structures were calculated by using the code system for management of reactor decommissioning (COSMARD), in which the work breakdown structures and the calculation models were contained. It was confirmed that the labor-hours could be easily estimated by COSMARD through the calculations. This report describes the labor-hour calculation models and application of these models to COSMARD. (author)

  14. Reserves for shutdown/dismantling and disposal in nuclear technology. Theses and recommendations on reform options

    International Nuclear Information System (INIS)

    Meyer, Bettina

    2012-01-01

    The study on reserves for shutdown, dismantling and disposal of nuclear facilities covers the following topics: cost for shutdown, dismantling and disposal and amount and transparency of nuclear reserves, solution by y stock regulated by public law for long-term liabilities, and improvement of the protection in the event of insolvency for the remaining EVU reserves for short- and intermediate-term liabilities. The appendix includes estimations and empirical values for the cost of shutdown and dismantling, estimation of disposal costs, and a summary of Swiss studies on dismantling and disposal and transfer to Germany.

  15. User Interface Technology to Reduce Mental Transformations for Tangible Remote Dismantling Simulator

    International Nuclear Information System (INIS)

    Hyun, Dongjun; Kim, Ikjune; Lee, Jonghwan; Kim, Geun-Ho; Jeong, Kwan-Seong; Choi, Byung-Seon; Moon, Jeikwon; Choi, Jong-Won

    2015-01-01

    High-level radiation of the major components restricts access by human workers, and makes an accident or outage during the dismantling process more difficult to deal with. Since unexpected situations causes waste of budget and an aggravation of safety, the preliminary verification of the dismantling processes and equipment by the tangible remote dismantling simulator is very important. The design optimization of the dismantling processes and equipment is one of the most important objectives of the tangible remote dismantling simulator, as well. This paper proposes a user interface technology to reduce mental transformations for the tangible remote dismantling simulator. At the dismantling process simulation using the tangible remote dismantling simulator, the most difficult work is the remote operation handling the high degrees-of-freedom (DOF) manipulator due to complex mental transformations. The proposed user interface technology reduces mental transformations with constraints using the point projection and direction projection. The test result of the cutting process over the closure head of the RPV demonstrates that the proposed mental transformation reduction technology is operated successfully in the tangible remote dismantling simulator, and lets the operator be easy to control the high DOF manipulator even in the most difficult operation by reducing DOFs to be controlled manually

  16. Microtubules become more dynamic but not shorter during preprophase band formation: A possible "search-and-capture" mechanism for microtubule translocation

    NARCIS (Netherlands)

    Vos, J.W.; Dogterom, M.; Emons, A.M.C.

    2004-01-01

    The dynamic behavior of the microtubule cytoskeleton plays a crucial role in cellular organization, but the physical mechanisms underlying microtubule (re)organization in plant cells are poorly understood. We investigated microtubule dynamics in tobacco BY-2 suspension cells during interphase and

  17. CRITICALITY CONTROL DURING THE DISMANTLING OF A URANIUM CONVERSION PLANT

    International Nuclear Information System (INIS)

    LADURELLE, Laurent; LISBONNE, Pierre

    2003-01-01

    Within the Commissariat a l'Energie Atomique, in the Cadarache Research Center in southern France, the production at the Enriched Uranium Treatment Workshops started in 1965 and ended in 1995. The dismantling is in progress and will last until 2006. The decommissioning is planned in 2007. Since the authorized enrichment in 235U was 10% in some parts of the plant, and unlimited in others, the equipment and procedures were designed for criticality control during the operating period. Despite the best previous removing of the uranium in the inner parts of the equipment, evaluation of the mass of remaining fissile material by in site gamma spectrometry measurement shows that the safety of the ''clean up'' operations requires specific criticality control procedures, this mass being higher than the safe mass. The chosen method is therefore based on the mapping of fissile material in the contaminated parts of the equipment and on the respect of particular rules set for meeting the criticality control standards through mass control. The process equipment is partitioned in separated campaign, and for each campaign the equipment dismantling is conducted with a precise traceability of the pieces, from the equipment to the drum of waste, and the best final evaluation of the mass of fissile material in the drum. The first results show that the mass of uranium found in the dismantled equipment is less than the previous evaluation, and they enable us to confirm that the criticality was safely controlled during the operations. The mass of fissile material remaining in the equipment can be then carefully calculated, when it is lower than the minimal critical mass, and on the basis of a safety analysis, we will be free of any constraints regarding criticality control, this allowing to make procedures easier, and to speed up the operations

  18. Recycling of concrete generated from Nuclear Power Plant dismantling

    International Nuclear Information System (INIS)

    Ogawa, Hideo; Nawa, Toyoharu; Ishikura, Takeshi; Tanaka, Hiroaki

    2013-01-01

    Reactor decommissioning required various technologies such as dismantling of facilities, decontamination, radioactivity measurement and recycling of dismantling wastes. This article discussed recycling of demolished concrete wastes. Dismantling of reactor building of large one unit of nuclear power plants would generate about 500 K tons of concrete wastes, about 98% of which was non-radioactive and could be used as base course material or backfill material after crushed to specified particle size. Since later part of 1990s, high quality recycled aggregate with specified limit of bone-dry density, water absorptivity and amount of fine aggregate had been developed from demolished concrete with 'Heat and rubbing method', 'Eccentric rotor method' and 'Screw grinding method' so as to separate cements attached to aggregate. Recycled aggregates were made from concrete debris with 'Jaw crusher' to particle size less than 40 mm and then particle size control or grinded by various grinding machines. Recycled fine aggregates made from crushing would have fragile site with cracks, air voids and bubbles. The author proposed quality improvement method to selectively separate fragile defects from recycled aggregates using weak grinding force, leaving attached pastes much and preventing fine particle generation as byproducts. This article outlined experiments to improve quality of recycled fine aggregates and their experimental results confirmed improvement of flow ability and compressive strength of mortal using recycled fine aggregates using 'Particle size selector' and 'Ball mill' so as to remove their fragile parts less than 2%. Mortal made from recycled fine aggregate could also prevent permeation of chloride ion. Recycled aggregate could be used for concrete instead of natural aggregate. (T. Tanaka)

  19. Stade. Decommissioning and dismantling of the nuclear power plant - from the nuclear power plant to the green lawn. 3. ed.

    International Nuclear Information System (INIS)

    2008-01-01

    The nuclear power plant Stade (KKS) was shutdown in 2003 and is being dismantled since 2005. The contribution covers the following issues: What means decommissioning and dismantling? What was the reason for decommissioning? What experiences on the dismantling of nuclear power plants are available? What is the dismantling procedure? What challenges for the power plant personal result from dismantling? What happens with the deconstruction material? What happens with the resulting free area (the ''green lawn'')? What is the legal frame work for dismantling?

  20. Association of TCTP with Centrosome and Microtubules

    Directory of Open Access Journals (Sweden)

    Mariusz K. Jaglarz

    2012-01-01

    Full Text Available Translationally Controlled Tumour Protein (TCTP associates with microtubules (MT, however, the details of this association are unknown. Here we analyze the relationship of TCTP with MTs and centrosomes in Xenopus laevis and mammalian cells using immunofluorescence, tagged TCTP expression and immunoelectron microscopy. We show that TCTP associates both with MTs and centrosomes at spindle poles when detected by species-specific antibodies and by Myc-XlTCTP expression in Xenopus and mammalian cells. However, when the antibodies against XlTCTP were used in mammalian cells, TCTP was detected exclusively in the centrosomes. These results suggest that a distinct pool of TCTP may be specific for, and associate with, the centrosomes. Double labelling for TCTP and γ-tubulin with immuno-gold electron microscopy in Xenopus laevis oogonia shows localization of TCTP at the periphery of the γ-tubulin-containing pericentriolar material (PCM enveloping the centriole. TCTP localizes in the close vicinity of, but not directly on the MTs in Xenopus ovary suggesting that this association requires unidentified linker proteins. Thus, we show for the first time: (1 the association of TCTP with centrosomes, (2 peripheral localization of TCTP in relation to the centriole and the γ-tubulin-containing PCM within the centrosome, and (3 the indirect association of TCTP with MTs.

  1. Foam decontamination of large nuclear components before dismantling

    International Nuclear Information System (INIS)

    Costes, J.R.; Sahut, C.

    1998-01-01

    Following some simple theoretical considerations, the authors show that foam compositions can be advantageously circulated them for a few hours in components requiring decontamination before dismantling. The technique is illustrated on six large ferritic steel valves, then on austenitic steel heat exchangers for which the Ce(III)/Ce(IV) redox pair was used to dissolve the chromium; Ce(III) was reoxidized by ozone injection into the foam vector gas. Biodegradable surfactants are sued in the process; tests have shown that the foaming power disappears after a few days, provided the final radioactive liquid waste is adjusted to neutral pH, allowing subsequent coprecipitation of concentration treatment. (author)

  2. Implementing robotics in the Department of Energy Dismantlement Program

    International Nuclear Information System (INIS)

    Jones, A.T.

    1997-01-01

    Since the end of the cold war, as our nuclear stockpile has decreased, the Department of Energy (DOE) has been working rapidly to safely dismantle weapons returned by the military. In order to be retired, weapons must be returned to the Pantex Plant in Amarillo, Texas. There they are reduced to their component parts. Although many of these parts are not hazardous, some, including certain explosive assemblies and radioactive materials, are sufficiently hazardous so that special handling systems are necessary. This paper will describe several of these systems developed by Sandia for Pantex and their technical basis

  3. Conception of dismantling cell for glove box with alpha contamination

    International Nuclear Information System (INIS)

    Mangin, D.

    1987-01-01

    The new dismantling cell of Valduc treats particularly alpha glove boxes. This cell is conceived to reduce the intervention inside for man with ventilated clothes and to reduce the volume of alpha wastes by utilization of manipulators and appropriate tools. The respect of low level norms (0.1 Ci/ton) for storage of alpha wastes conductes us to make a first decontamination, to ameliorate the detection in quantity of plutonium in the wastes and for wastes with a level upper the norm to make studies on decontamination by Freon 113 [fr

  4. Metal Radioactive Waste Recycling from the Dismantling of Nuclear Facilities

    International Nuclear Information System (INIS)

    Fajt, B.; Prah, M.

    1996-01-01

    In the dismantling process of nuclear power plants a large amount of metal residues are generated. The residues of interest are stainless steel, copper and aluminium and can be reprocessed either for restricted or unrestricted use. Although there are many questions about the further use of these materials it should be convenient to recycle them. This paper discusses the complexity of the management of these metals. The radiation protection requirements are the most important principles. For these purposes great efforts in the decontamination have to be made. Regulatory aspects, clearance levels as well as characteristic of steel recycling industry, radiological impact and new developments are discussed. (author)

  5. Cost effective decommissioning and dismantling of nuclear power plants

    International Nuclear Information System (INIS)

    Wasinger, Karl

    2012-01-01

    As for any large and complex project, the basis for cost effective decommissioning and dismantling of nuclear power plants is established with the development of the project. Just as its construction, dismantling of a nuclear power plant is similarly demanding. Daily changing situations due to the progress of construction - in the present case progress of dismantling - result in significant logistical challenges for project managers and site supervisors. This will be aggravated by the fact that a considerable amount of the removed parts are contaminated or even activated. Hence, not only occupational health, safety and environmental protection is to be assured, employees, public and environment are to be adequately protected against the adverse effect of radioactive radiation as well. Work progress and not least expenses involved with the undertaking depend on adherence to the planned course of actions. Probably the most frequent cause of deviation from originally planned durations and costs of a project are disruptions in the flow of work. For being enabled to counteract in a timely and efficient manner, all required activities are to be comprehensively captured with the initial planning. The effect initial activities may have on subsequent works until completion must particularly be investigated. This is the more important the larger and more complex the project actually are. Comprehensive knowledge of all the matters which may affect the progress of the works is required in order to set up a suitable work break-down structure; such work break-down structure being indispensable for successful control and monitoring of the project. In building the related organizational structure of the project, all such stakeholders not being direct part of the project team but which may potentially affect the progress of the project are to be considered as well. Cost effective and lost time injury free dismantling of decommissioned nuclear power plants is based on implementing

  6. Decommissioning and dismantling of the Rossendorf Isotope Production

    International Nuclear Information System (INIS)

    Grahnert, Thomas

    2016-01-01

    After just over 40 years of production operation 2000, the operation of the Rossendorf Isotope Production was finally stopped. In the last few years of production already sections of the Rossendorf Isotope Production have been decommissioned. With the end of the isotope production the decommissioning of the entire complex started. In the two-part report, the decommissioning and dismantling of the Rossendorf Isotope production is presented. In part 1 (atw 5/2016) mainly the authorisation procedures and the realised decommissioning concept are presented. Part 2 (atw 6/2016) deals with special selected aspects of the implementation of the decommissioning programme.

  7. Latest expertise investigations in nuclear dismantling and industrial applications

    International Nuclear Information System (INIS)

    Gallozzi Ulmann, Adrien; Chazalet, Julien; Couturier, Pierre; Touzain, Etienne; Amgarou, Khalil; Menaa, Nabil

    2013-06-01

    During the last decades, CANBERRA has developed know-how, expertise and intervention strategies based on its feedback experiences in many countries. This document covers a wide range of applications involving nuclear characterization, for which CANBERRA is able to provide measurement set-up and results, activity characterization and radioactive source localization, as well as to guarantee safety or process thresholds corresponding to the customer's needs. To improve processes best-in-class methodology, know-how and tools have been used in complex examples described in this paper. CANBERRA has demonstrated its ability to better and efficiently prepare for and execute decontamination and dismantling activities. (authors)

  8. Some steps of the dismantling of the hot cell ATTILA

    International Nuclear Information System (INIS)

    Terrasson, L.

    1989-01-01

    This paper describes the dismantling, during 2 years and just finished now, of a large hot cell (11.6 m x 5.90 m x 5.80 m) at Fontenay-aux-Roses (France) characterised by an importand irradiation and contamination mean dose rate 7 rads/hr, in some places 20 rads/hr, coming at 98 % from Cesium 137 (beta decay radioisotope). Put into operation in March 1967, the Attila cell was used for spent fuel processing using halogenides [fr

  9. Fabrication of mixed oxide fuel using plutonium from dismantled weapons

    International Nuclear Information System (INIS)

    Blair, H.T.; Chidester, K.; Ramsey, K.B.

    1996-01-01

    A very brief summary is presented of experimental studies performed to support the use of plutonium from dismantled weapons in fabricating mixed oxide (MOX) fuel for commercial power reactors. Thermal treatment tests were performed on plutonium dioxide powder to determine if an effective dry gallium removal process could be devised. Fabrication tests were performed to determine the effects of various processing parameters on pellet quality. Thermal tests results showed that the final gallium content is highly dependent on the treatment temperature. Fabrication tests showed that the milling process, sintering parameters, and uranium feed did effect pellet properties. 1 ref., 1 tab

  10. Griseofulvin stabilizes microtubule dynamics, activates p53 and inhibits the proliferation of MCF-7 cells synergistically with vinblastine

    International Nuclear Information System (INIS)

    Rathinasamy, Krishnan; Jindal, Bhavya; Asthana, Jayant; Singh, Parminder; Balaji, Petety V; Panda, Dulal

    2010-01-01

    Griseofulvin, an antifungal drug, has recently been shown to inhibit proliferation of various types of cancer cells and to inhibit tumor growth in athymic mice. Due to its low toxicity, griseofulvin has drawn considerable attention for its potential use in cancer chemotherapy. This work aims to understand how griseofulvin suppresses microtubule dynamics in living cells and sought to elucidate the antimitotic and antiproliferative action of the drug. The effects of griseofulvin on the dynamics of individual microtubules in live MCF-7 cells were measured by confocal microscopy. Immunofluorescence microscopy, western blotting and flow cytometry were used to analyze the effects of griseofulvin on spindle microtubule organization, cell cycle progression and apoptosis. Further, interactions of purified tubulin with griseofulvin were studied in vitro by spectrophotometry and spectrofluorimetry. Docking analysis was performed using autodock4 and LigandFit module of Discovery Studio 2.1. Griseofulvin strongly suppressed the dynamic instability of individual microtubules in live MCF-7 cells by reducing the rate and extent of the growing and shortening phases. At or near half-maximal proliferation inhibitory concentration, griseofulvin dampened the dynamicity of microtubules in MCF-7 cells without significantly disrupting the microtubule network. Griseofulvin-induced mitotic arrest was associated with several mitotic abnormalities like misaligned chromosomes, multipolar spindles, misegregated chromosomes resulting in cells containing fragmented nuclei. These fragmented nuclei were found to contain increased concentration of p53. Using both computational and experimental approaches, we provided evidence suggesting that griseofulvin binds to tubulin in two different sites; one site overlaps with the paclitaxel binding site while the second site is located at the αβ intra-dimer interface. In combination studies, griseofulvin and vinblastine were found to exert synergistic

  11. Remote Fiber Laser Cutting System for Dismantling Glass Melter - 13071

    Energy Technology Data Exchange (ETDEWEB)

    Mitsui, Takashi; Miura, Noriaki [IHI Corporation, 1 Shin-Nakahara-cho, Isogo-ku, Yokohama, Kanagawa (Japan); Oowaki, Katsura; Kawaguchi, Isao [IHI Inspection and Instrumentation Co., Ltd, 1 Shin-Nakahara-cho, Isogo-ku, Yokohama, Kanagawa (Japan); Miura, Yasuhiko; Ino, Tooru [Japan Nuclear Fuel Limited, 4-108, Aza Okitsuke, Oaza Obuchi, Rokkasho-Mura, Kamikita-gun, Aomori (Japan)

    2013-07-01

    Since 2008, the equipment for dismantling the used glass melter has been developed in High-level Liquid Waste (HLW) Vitrification Facility in the Japanese Rokkasho Reprocessing Plant (RRP). Due to the high radioactivity of the glass melter, the equipment requires a fully-remote operation in the vitrification cell. The remote fiber laser cutting system was adopted as one of the major pieces of equipment. An output power of fiber laser is typically higher than other types of laser and so can provide high-cutting performance. The fiber laser can cut thick stainless steel and Inconel, which are parts of the glass melter such as casings, electrodes and nozzles. As a result, it can make the whole of the dismantling work efficiently done for a shorter period. Various conditions of the cutting test have been evaluated in the process of developing the remote fiber cutting system. In addition, the expected remote operations of the power manipulator with the laser torch have been fully verified and optimized using 3D simulations. (authors)

  12. Dismantling method for reactor shielding wall and device therefor

    International Nuclear Information System (INIS)

    Akagawa, Katsuhiko.

    1995-01-01

    A ring member having an outer diameter slightly smaller than an inner diameter of a reactor shielding wall to be dismantled is lowered in the inside of the reactor shielding wall while keeping a horizontal posture. A cutting device is disposed at the lower peripheral edge of the ring member. The cutting device can move along the peripheral edge of the circular shape of the ring member. The ring member is urged against the inner surface of the reactor shielding wall by using an urging member to immobilize the ring member. Then, the cutting device is operated to cut the reactor shielding wall into a plurality of ring-like blocks at a plurality of inner horizontal ribs or block connection ribs. Then, the blocks of the cut reactor shielding wall are supported by the ring member, and transported out of the reactor container by a lift. The cut blocks transported to the outside are finely dismantled for every block in a closed chamber. (I.N.)

  13. Method of freezing type dismantling for wasted reactors

    International Nuclear Information System (INIS)

    Tatsumi, Toshiyuki.

    1985-01-01

    Purpose: To enable to operate a cutting device in the air by placing a working table on ice while utilizing the ice as radiation shielding materials thereby prevent the diffusion of air contaminations. Method: Upon dismantling a BWR type reactor, ice is packed into a reactor container and a pressure vessel and frozen state is maintained by cooling coils disposed to the outer circumference of the pressure vessel. Then, an airtight hood is covered over the pressure vessel and a working table is rotatably disposed therein. Upon working, when the upper layer ice is melted by a heat pump and discharged, the airtight hood is lowered to a predetermined level. After freezing the melted portion again at the lowered level, cutting work is conducted by an operator in the hood. The cut pieces are conveyed after hoisting the airtight hood by a crane. The pressure vessel is dismantled by repeating the foregoing procedures. In this way, cut pieces can be recovered without falling them to the reactor bottom as in the conventional work in water. In addition, since the procedures are conducted while covering the airtight hood, diffusion of air contaminations can be prevented. (Kamimura, M.)

  14. A Study on Dismantling of Westinghouse Type Nuclear Reactor

    International Nuclear Information System (INIS)

    Jeong, Woo-Tae; Lee, Sang-Guk

    2014-01-01

    KHNP started a research project this year to develop a methodology to dismantle nuclear reactors and internals. In this paper, we reviewed 3D design model of the reactor and suggested feasible cutting scheme.. Using 3-D CAD model of Westinghouse type nuclear reactor and its internals, we reviewed possible options for disposal. Among various options of dismantling the nuclear reactor, plasma cutting was selected to be the best feasible and economical method. The upper internals could be segmented by using a band saw. It is relatively fast, and easily maintained. For cutting the lower internals, plasma torch was chosen to be the best efficient tool. Disassembling the baffle and the former plate by removing the baffle former bolts was also recommended for minimizing storage volume. When using plasma torch for cutting the reactor vessel and its internal, installation of a ventilation system for preventing pollution of atmosphere was recommended. For minimizing radiation exposure during the cutting operation, remotely controlled robotic tool was recommended to be used

  15. The UK's National Programme for IT: Why was it dismantled?

    Science.gov (United States)

    Justinia, Taghreed

    2017-02-01

    This paper discusses the UK's National Programme for IT (NPfIT), which was an ambitious programme launched in 2002 with an initial budget of some £6.2 billion. It attempted to implement a top-down digitization of healthcare in England's National Health Service (NHS). The core aim of the NPfIT was to bring the NHS' use of information technology into the 21st century, through the introduction of an integrated electronic patient record systems, and reforming the way that the NHS uses information, and hence to improve services and the quality of patient care. The initiative was not trusted by doctors and appeared to have no impact on patient safety. The project was marred by resistance due to the inappropriateness of a centralized authority making top-down decisions on behalf of local organizations. The NPfIT was officially dismantled in September 2011. Deemed the world's largest civil IT programme, its failure and ultimate demise sparked a lot of interest as to the reasons why. This paper summarises the underlying causes that lead to dismantling the NPfIT. At the forefront of those circumstances were the lack of adequate end user engagement, the absence of a phased change management approach, and underestimating the scale of the project.

  16. SGN's Dismantling and Decommissioning engineering, projects experience and capabilities

    International Nuclear Information System (INIS)

    Destrait, L.

    1998-01-01

    Its experience in waste treatment, conditioning, storage and disposal, its cooperation with CEA and COGEMA Group in license agreements give SGN expertise in the decommissioning field. SGN's experience and background in all areas of nuclear facility decommissioning, such as chemical and mechanical cells, nuclear advanced reactors, reprocessing facilities result in fruitful references to the customers. The poster is presenting different achievements and projects with SGN's participation such as: - The decommissioning of Windscale Advanced Gas cooled Reactors (WAGR), in particular providing methodology and equipment to dismantle the Pressure and Insulation Vessel of the reactor. - The decommissioning plan of Ignalina (Lithuania) and Paldiski (Estonia), defining strategies, scenarios, necessary equipments and tools and choosing the best solutions to decommission the site under different influencing parameters such as cost, dose rate exposure, etc... - Th One Site Assistance Team (OSAT) at Chernobyl regarding the preparation works for the waste management and decommissioning of the plant. - The decommissioning of French nuclear facilities such as reprocessing (UP1) and reactor (EL4) plants. The important experience acquired during the facility management and during the first dismantling and decommissioning operations is an important factor for the smooth running of these techniques for the future. The challenge to come is to control all the operations, the choice of strategies, the waste management, the efficiency of tools and equipments, and to provide nuclear operators with a full range of proven techniques to optimise costs and minimize decommissioning personnel exposure. (Author)

  17. Dismantling of the research reactor RTS-1 Galileo Galilei in Pisa (Italy)

    International Nuclear Information System (INIS)

    Ruiz Martinez, J. t.; Farella, G.; Cimini, E.; Russo, M.

    2014-01-01

    This paper is about the most relevant aspects of the first phase of the dismantling, removal of the water in the pool, prior treatment through evaporation, the dismantling of all the submerged activated elements and other activated or contaminated elements that have been part of the nuclear facility. (Author)

  18. Know History, Know Self: Art Therapists' Responsibility to Dismantle White Supremacy

    Science.gov (United States)

    Hamrick, Cassie; Byma, Christine

    2017-01-01

    In this article, we call on white art therapists to assume responsibility for dismantling white supremacy in the field of art therapy, in personal as well as political-structural arenas. We respond to calls from scholars and writers of color for white people to assume increased responsibility for dismantling white supremacy in white communities…

  19. A treaty more alarming than efficient. The dismantled warheads will not be destroyed. Danger

    International Nuclear Information System (INIS)

    Riche, P.; Despic-Popovic, H.; Nougayrede, N.

    2002-01-01

    This political analysis presents the new treaty of nuclear weapons dismantling between Russia and Usa. In fact the warheads will not be completely dismantling but only stocked, leading to a possible recovery by terrorists. It underlines the real interests of this agreement which are more economic than peaceful. (A.L.B.)

  20. Note n. SD3-DEM-01 regulations procedures relative to the based nuclear installations dismantling

    International Nuclear Information System (INIS)

    2003-02-01

    This note aims to define the regulations procedures relative to the safety of based nuclear installations dismantling defined by the decree of the 11 december 1963 modified. The first part describes the two main phases of a based nuclear installation life, the operating and the dismantling phase. The second part is devoted to the procedures. (A.L.B.)

  1. Dismantling of an alpha contaminated hot cell at the Marcoule Pilot Plant

    International Nuclear Information System (INIS)

    Tachon, M.

    1988-01-01

    For the remodeling of Marcoule Pilot Plant, the cell 82: old unit for plutonium solution purification by extraction, was dismantled. About 42 tons of wastes were evacuated. Some wastes wen decontaminated by mechanical means other wastes with higher residual activity were stored for subsequent processing. The operation shows that dismantling of a hot cell is possible even if incorporated in an operating plant [fr

  2. Decontamination and dismantling at the CEA; L'assainissement et le demantelement au CEA

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    This document presents the dismantling policy at the CEA (French Research Center on the atomic energy), the financing of the decontamination and the dismantling, the regulatory framework, the knowledge and the technology developed at the CEA, the radiation protection, the environment monitoring and the installations. (A.L.B.)

  3. Melanophores for microtubule dynamics and motility assays.

    Science.gov (United States)

    Ikeda, Kazuho; Semenova, Irina; Zhapparova, Olga; Rodionov, Vladimir

    2010-01-01

    Microtubules (MTs) are cytoskeletal structures essential for cell division, locomotion, intracellular transport, and spatial organization of the cytoplasm. In most interphase cells, MTs are organized into a polarized radial array with minus-ends clustered at the centrosome and plus-ends extended to the cell periphery. This array directs transport of organelles driven by MT-based motor proteins that specifically move either to plus- or to minus-ends. Along with using MTs as tracks for cargo, motor proteins can organize MTs into a radial array in the absence of the centrosome. Transport of organelles and motor-dependent radial organization of MTs require MT dynamics, continuous addition and loss of tubulin subunits at minus- and plus-ends. A unique experimental system for studying the role of MT dynamics in these processes is the melanophore, which provides a useful tool for imaging of both dynamic MTs and moving membrane organelles. Melanophores are filled with pigment granules that are synchronously transported by motor proteins in response to hormonal stimuli. The flat shape of the cell and the radial organization of MTs facilitate imaging of dynamic MT plus-ends and monitoring of their interaction with membrane organelles. Microsurgically produced cytoplasmic fragments of melanophores are used to study the centrosome-independent rearrangement of MTs into a radial array. Here we describe the experimental approaches to study the role of MT dynamics in intracellular transport and centrosome-independent MT organization in melanophores. We focus on the preparation of cell cultures, microsurgery and microinjection, fluorescence labeling, and live imaging of MTs. 2010 Elsevier Inc. All rights reserved.

  4. Process for the dismantling of buried equipment, with a contamination risk and eventually irradiating, and intervention enclosure for this process

    International Nuclear Information System (INIS)

    Bodin, F.; Saublet, J.C.

    1991-01-01

    Dismantling of buried equipment, for instance abandoned effluent pipes,is made by unitary sections under mobile enclosure with a self-supporting structure and a floor provided with a long central aperture giving access to the section to dismantle

  5. Quantitative Analysis of Tau-Microtubule Interaction Using FRET

    Directory of Open Access Journals (Sweden)

    Isabelle L. Di Maïo

    2014-08-01

    Full Text Available The interaction between the microtubule associated protein, tau and the microtubules is investigated. A fluorescence resonance energy transfer (FRET assay was used to determine the distance separating tau to the microtubule wall, as well as the binding parameters of the interaction. By using microtubules stabilized with Flutax-2 as donor and tau labeled with rhodamine as acceptor, a donor-to-acceptor distance of 54 ± 1 Å was found. A molecular model is proposed in which Flutax-2 is directly accessible to tau-rhodamine molecules for energy transfer. By titration, we calculated the stoichiometric dissociation constant to be equal to 1.0 ± 0.5 µM. The influence of the C-terminal tails of αβ-tubulin on the tau-microtubule interaction is presented once a procedure to form homogeneous solution of cleaved tubulin has been determined. The results indicate that the C-terminal tails of α- and β-tubulin by electrostatic effects and of recruitment seem to be involved in the binding mechanism of tau.

  6. Kinesin expands and stabilizes the GDP-microtubule lattice

    Science.gov (United States)

    Peet, Daniel R.; Burroughs, Nigel J.; Cross, Robert A.

    2018-05-01

    Kinesin-1 is a nanoscale molecular motor that walks towards the fast-growing (plus) ends of microtubules, hauling molecular cargo to specific reaction sites in cells. Kinesin-driven transport is central to the self-organization of eukaryotic cells and shows great promise as a tool for nano-engineering1. Recent work hints that kinesin may also play a role in modulating the stability of its microtubule track, both in vitro2,3 and in vivo4, but the results are conflicting5-7 and the mechanisms are unclear. Here, we report a new dimension to the kinesin-microtubule interaction, whereby strong-binding state (adenosine triphosphate (ATP)-bound and apo) kinesin-1 motor domains inhibit the shrinkage of guanosine diphosphate (GDP) microtubules by up to two orders of magnitude and expand their lattice spacing by 1.6%. Our data reveal an unexpected mechanism by which the mechanochemical cycles of kinesin and tubulin interlock, and so allow motile kinesins to influence the structure, stability and mechanics of their microtubule track.

  7. Study on applicability of evaluation model of manpower needs for dismantling of equipments in FUGEN-1. Dismantling process in 3rd/4th feedwater heater room

    International Nuclear Information System (INIS)

    Shibahara, Yuji; Izumi, Masanori; Nanko, Takashi; Tachibana, Mitsuo; Ishigami, Tsutomu

    2010-10-01

    Manpower needs for the dismantling process on the dismantling of equipments in FUGEN 3rd/4th feedwater heater room was calculated with the management data evaluation system (PRODIA Code), and it was inspected whether the conventional evaluation model had applicability for FUGEN or not. It was confirmed that the conventional evaluation model for feedwater heater had no applicability. In comparison of the calculated value with the actual data, we found two difference: 1) the calculated value were significantly larger than the actual data, 2) the actual data for the dismantling of 3rd feedwater heater was twice larger than that of 4th feedwater heater, though these equipments were almost same weight. It was found that these were brought 1) by the difference in the work descriptions of dismantling between JPDR and FUGEN, and 2) by that in the cutting number between 3rd feedwater heater and 4th one. The manpower needs for the dismantling of both feedwater heaters were calculated with a new calculation equation reflecting the descriptions of dismantling, and it was found that these results showed the good agreement with the actual data. (author)

  8. Experience of partial dismantling and large component removal of light water reactors

    International Nuclear Information System (INIS)

    Dubourg, M.

    1987-01-01

    Not any of the French PWR reactors need to be decommissioned before the next decade or early 2000. However, feasibility studies of decommissioning have been undertaken and several dismantling scenarios have been considered including the dismantling of four PWR units and the on-site entombment of the active components into a reactor building for interim disposal. In addition to theoretical evaluation of radwaste volume and activity, several operations of partial dismantling of active components and decontamination activities have been conducted in view of dismantling for both PWR and BWR units. By analyzing the concept of both 900 and 1300 MWe PWR's, it appears that the design improvements taken into account for reducing occupational dose exposure of maintenance personnel and the development of automated tools for performing maintenance and repairs of major components, contribute to facilitate future dismantling and decommissioning operations

  9. Development of an augmented reality based simulation system for cooperative plant dismantling work

    International Nuclear Information System (INIS)

    Ishii, Hirotake; Man, Zhiyuan; Yan, Weida; Shimoda, Hiroshi; Izumi, Masanori

    2015-01-01

    An augmented reality-based simulation system for cooperative plant dismantling work has been developed and evaluated. In the system, behaviors of virtual objects such as the dismantling target, chain blocks, and trolleys are physically simulated. Their appearance is superimposed on camera images captured with cameras on users' tablet devices. The users can manipulate virtual objects cooperatively via touch operation. They can cut the dismantling targets, lift them on the trolleys using chain blocks, and convey them through narrow passages to ascertain whether the dismantling targets can be conducted without colliding with the passages. During the simulation, collisions between the virtual objects and real work environment are detected based on their three-dimensional shape data measured in advance. The collided parts are visualized using augmented reality superimposition. Four evaluators assessed the simulation system. Results show that the simulation system can be useful for prior examination of dismantling works, but some points were also found to need improvement. (author)

  10. Decision support system for the dismantling of building in nuclear facilities

    International Nuclear Information System (INIS)

    Zeiher, M.

    2009-01-01

    In case of decommissioning and dismantling the complex structure of nuclear facilities requires a thorough selection of dismantling methods and a detailed operations planning. The decision for an appropriate technology with respect to economic, environmental and radiation protection aspects has to take into account that the different procedural steps are coordinated. Component specific boundary conditions and process parameters have to be considered. A data base was established that includes the process parameters for different dismantling methodologies. The next step is the determination of specific requirements of plant operators and engineers in order to identify the tasks in the frame of the dismantling process. The authors describes the decision support algorithm that allows to enhance the dismantling efficiency.

  11. Transparency in nuclear warhead dismantlement -- Limited chain of custody and warhead signatures

    International Nuclear Information System (INIS)

    Kiernan, G.; Percival, M.; Bratcher, L.

    1996-01-01

    The goal of the US Safeguards, Transparency, and Irreversibility (STI) initiative is the development of a series of transparency measures that provide confidence that nuclear warheads are actually being dismantled and that the fissile material being removed from these dismantled weapons is not recycled into new production. A limited chain of custody (LCC) would follow a warhead from the time it is declared excess until it is actually dismantled and the fissile materials are stored. Measurement of warhead signatures is an option in LCC using radiation detection techniques to confirm that a warhead has been dismantled, without intrusive inspections within the dismantlement facility. This paper discusses LCC and warhead signatures as well as indicate first results of laboratory measurements related to warhead signatures

  12. Mock-up test of remote controlled dismantling apparatus for large-sized vessels (contract research)

    Energy Technology Data Exchange (ETDEWEB)

    Myodo, Masato; Miyajima, Kazutoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Okane, Shogo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    2001-03-01

    The Remote dismantling apparatus, which is equipped with multi-units for functioning of washing, cutting, collection of cut pieces and so on, has been constructed to dismantle the large-sized vessels in the JAERI's Reprocessing Test Facility (JRTF). The apparatus has five-axis movement capability and its operation is performed remotely. The mock-up tests were performed to evaluate the applicability of the apparatus to actual dismantling activities by using the mock-ups of LV-3 and LV-5 in the facility. It was confirmed that each unit was satisfactory functioned by remote operation. Efficient procedures for dismantling the large-sized vessel was studied and various date was obtained in the mock-up tests. This apparatus was found to be applicable for the actual dismantling activity in JRTF. (author)

  13. Chooz A: a model for the dismantling of water-cooled reactors

    International Nuclear Information System (INIS)

    Anon.

    2017-01-01

    The specificity of Chooz-A, the first French pressurized water reactor (PWR), is that the reactor and its major components (pumps, exchangers and cooling circuits) are installed in 2 caves dug out in a hill slope. Chooz-A was operating from 1967 to 1991, in 1993 the fuel was removed and in 2007 EDF received the authorization to dismantle the reactor. In 2012, EDF completed the dismantling of the cave containing the elements of the cooling circuit, a cornerstone was the removing of the four 14 m high steam generators. The dismantling of the pressure vessel began in march 2017, it is the same tools and the same processes that were used for the dismantling of the pressure vessel of the Zorita plant (Spain) in 2016. The end of the Chooz-A dismantling is expected in 2022. The feedback experience will help to standardize practices for the French fleet of PWRs. (A.C.)

  14. Evaluation methodology of a manipulator actuator for the dismantling process during nuclear decommissioning

    International Nuclear Information System (INIS)

    Park, Jongwon; Kim, Chang-Hoi; Jeong, Kyung-min; Choi, Byung-Seon; Moon, Jeikwon

    2016-01-01

    Highlights: • A methodology to evaluate actuators of a dismantling manipulator. • Evaluation criteria for choosing the most suitable actuator type. • A mathematical evaluation model for evaluation. • The evaluation method is expected to be used for determining other manipulators. - Abstract: This paper presents a methodology to evaluate actuators of a manipulator for dismantling nuclear power plants. Actuators are the most dominant components because a dismantling manipulator relies heavily on the actuator type used. To select the most suitable actuator, evaluation criteria are presented in four categories based on the nuclear dismantling environment. A mathematical model is presented and evaluation results are calculated with weights and scores for each criterion. The proposed evaluation method is expected to be used for determining other aspects of the design of dismantling manipulators.

  15. Mock-up test of remote controlled dismantling apparatus for large-sized vessels (contract research)

    International Nuclear Information System (INIS)

    Myodo, Masato; Miyajima, Kazutoshi; Okane, Shogo

    2001-03-01

    The Remote dismantling apparatus, which is equipped with multi-units for functioning of washing, cutting, collection of cut pieces and so on, has been constructed to dismantle the large-sized vessels in the JAERI's Reprocessing Test Facility (JRTF). The apparatus has five-axis movement capability and its operation is performed remotely. The mock-up tests were performed to evaluate the applicability of the apparatus to actual dismantling activities by using the mock-ups of LV-3 and LV-5 in the facility. It was confirmed that each unit was satisfactory functioned by remote operation. Efficient procedures for dismantling the large-sized vessel was studied and various date was obtained in the mock-up tests. This apparatus was found to be applicable for the actual dismantling activity in JRTF. (author)

  16. S.T.M.I.: Several years of experience in nuclear plant dismantling

    International Nuclear Information System (INIS)

    Moreau, J.C.

    1986-01-01

    Since 1977, when STMI performed its first dismantling operation, the Company appreciably improved in that field through important operations: the dismantling of the calciothermy and fluoration metal Pu preparation facility, in La Hague reprocessing plant, the dismantling of the slag treatment chain, associated to calciothermy and fluoration processes, in La Hague reprocessing plant, the cleaning of EL4 cell in Marcoule. To perform these operations, STMI's operating teams, on top of decontamination and dismantling technologies, strived to improve handling and transportation technologies, and to nuclearize many equipments. In order to increase its technical efficiency, STMI signed a cooperation agreement with TECHNICATOME company. Therefore, the union between the operational know-hows of STMI and the design experience of TECHNICATOME allow the needs of any customs facing a dismantling case to be satisfied [fr

  17. Microtubule depolymerization normalizes in vivo myocardial contractile function in dogs with pressure-overload left ventricular hypertrophy

    Science.gov (United States)

    Koide, M.; Hamawaki, M.; Narishige, T.; Sato, H.; Nemoto, S.; DeFreyte, G.; Zile, M. R.; Cooper G, I. V.; Carabello, B. A.

    2000-01-01

    BACKGROUND: Because initially compensatory myocardial hypertrophy in response to pressure overloading may eventually decompensate to myocardial failure, mechanisms responsible for this transition have long been sought. One such mechanism established in vitro is densification of the cellular microtubule network, which imposes a viscous load that inhibits cardiocyte contraction. METHODS AND RESULTS: In the present study, we extended this in vitro finding to the in vivo level and tested the hypothesis that this cytoskeletal abnormality is important in the in vivo contractile dysfunction that occurs in experimental aortic stenosis in the adult dog. In 8 dogs in which gradual stenosis of the ascending aorta had caused severe left ventricular (LV) pressure overloading (gradient, 152+/-16 mm Hg) with contractile dysfunction, LV function was measured at baseline and 1 hour after the intravenous administration of colchicine. Cardiocytes obtained by biopsy before and after in vivo colchicine administration were examined in tandem. Microtubule depolymerization restored LV contractile function both in vivo and in vitro. CONCLUSIONS: These and additional corroborative data show that increased cardiocyte microtubule network density is an important mechanism for the ventricular contractile dysfunction that develops in large mammals with adult-onset pressure-overload-induced cardiac hypertrophy.

  18. 48 CFR 52.249-3 - Termination for Convenience of the Government (Dismantling, Demolition, or Removal of Improvements).

    Science.gov (United States)

    2010-10-01

    ... Convenience of the Government (Dismantling, Demolition, or Removal of Improvements). 52.249-3 Section 52.249-3... Convenience of the Government (Dismantling, Demolition, or Removal of Improvements). As prescribed in 49.502(b)(2), insert the following clause: Termination for Convenience of the Government (Dismantling...

  19. CENTROSOMES AND MICROTUBULES DURING MEIOSIS IN THE MUSHROOM BOLETUS RUBINELLUS

    Science.gov (United States)

    McLaughlin, David J.

    1971-01-01

    The double centrosome in the basidium of Boletus rubinellus has been observed in three planes with the electron microscope at interphase preceding nuclear fusion, at prophase I, and at interphase I. It is composed of two components connected by a band-shaped middle part. At anaphase I a single, enlarged centrosome is found at the spindle pole, which is attached to the cell membrane. Microtubules mainly oriented parallel to the longitudinal axis of the basidium are present at prefusion, prophase I and interphase I. Cytoplasmic microtubules are absent when the spindle is present. The relationship of the centrosome in B. rubinellus to that in other organisms and the role of the cytoplasmic microtubules are discussed. PMID:4329156

  20. Cost Savings through Innovation in Decontamination, Decommissioning, and Dismantlement

    International Nuclear Information System (INIS)

    Yancey, Neal A.

    2003-01-01

    The United States Department of Energy (DOE) continually seeks safer and more cost effective technologies for the decontamination and decommissioning (D and D) of nuclear facilities. The Deactivation and Decommissioning Focus Area (DDFA) of the DOE's Office of Science and Technology (OST) sponsored large-scale demonstration and deployment projects (LSDDPs) to help bring new technologies into the D and D programs. The Idaho National Engineering and Environmental Laboratory (INEEL) LSDDP generated a list of needs defining specific problems where improved technologies could be incorporated into ongoing D and D tasks. The needs fell into 5 major categories--characterization, dismantlement, safety, material dispositioning, and decontamination. Technologies were carefully selected that provide a large benefit for a small investment. The technologies must provide significant improvements in cost, safety, radiation exposure, waste volume reduction, or schedule savings and widely applicable throughout the DOE complex. The LSDDP project provided training for the new technologies and worked with technology suppliers to resolve any questions that arose. Since 1998, 26 technologies have been demonstrated or deployed through the LSDDP for the D and D program at the INEEL. Of the 26 demonstrated and deployed technologies, 14 were in characterization, 3 were in decontamination, 4 were in dismantlement, 3 were in safety, and 2 were in material dispositioning. To promote the use of these technologies at other sites within the DOE complex, the LSDDP team published fact sheets, videos, technology summary reports, articles in INEEL star newspaper, posters, and maintained an internet home page on the project. As a result, additional deployments have taken place at the Hanford, Mound, Fernald, Oak Ridge, Ashtabula, and West Valley. Eight of the 26 technologies evaluated were developed in foreign countries. The technologies demonstrated have been shown to be faster, less expensive, and

  1. Dismantling of Evaporators by Laser Cutting Measurement of Secondary Emissions

    International Nuclear Information System (INIS)

    Pilot, Guy; Fauvel, Sylvain; Gosse, Xavier; De Dinechin, Guillaume

    2006-01-01

    In order to dismantle the evaporators of an obsolete reprocessing plant in Marcoule, studies were carried out by IRSN (Institut de Radioprotection et de Surete Nucleaire) / DSU/SERAC in cooperation with CEA (power laser group) on the laser cutting of steel structures, on the request of COGEMA (now AREVA NC) /Marcoule (UP1 dismantling project manager) and CEA/UMODD (UP1 dismantling owner). The aim of these studies was: - to quantify and to characterize the secondary emissions produced by Nd-YAG laser cutting of Uranus 65 steel pieces representative of UP1 evaporator elements and to examine the influence of different parameters, - to qualify a pre-filtration technique and particularly an electrostatic precipitator, - to compare the Nd-YAG used with other cutting tools previously studied. The experiments, which took place in a 35 m 3 ventilated cutting cell, allow to underline the following points: for the Uranus 65 steel, the sedimented dross, the deposits on the walls of the cutting cell and the aerosols drawn in the ventilation exhaust duct (∼ 275 m 3 /h), represent respectively between 92% and 99%, between 0.01% and 0.25% and between 1% and 8% of the total collected mass, the attached slag varies much from one configuration to the other and can sometimes amount to a relatively important fraction of the total mass, the kerves vary from 2 mm up to 7 mm for the Uranus 65 steel plates (thickness: 13.8 mm for the single plate and 12.8 + 3.5 mm for the double plate), the exhausted aerosol mass per cut length (g/m) decreases with the cutting speed, varies neither with the stand-off nor with the gas pressure, is dependent upon the gas nature (for the double plate), increases with the laser power, is strongly affected by the nature of the steel (stainless steel or mild steel) and is independent upon the plate position, the size distribution of aerosols is multimodal with a main mode often around 0.45 μm, the electrostatic precipitator has been a satisfactory prefilter

  2. Experience acquired by EDF in implementation of its dismantling programme

    Energy Technology Data Exchange (ETDEWEB)

    Klaeyle, S.; Dalmas, R.; Davoust, M. [EDF - Centre d' Ingenerie Deconstruction Environnement (CIDEN), 69 - Villeurbanne (France)

    2008-07-01

    EDF decided in 2001 to implement immediate dismantling of its first generation nuclear plants. Seven years after this decision, the physical progress of the programme is 24% and is due to reach 50 % by 2013. This paper presents the experiences acquired in the fields of organization, project and programme management, purchasing strategies and waste management. Until now, the principal works involve Brennilis (Heavy water), ChoozA (PWR) and Creys Malville (fast breeder reactor). The detailed pre-project concerning the first of the six gas graphite reactors is complete and the call for bids process has been launched. The organization to manage projects, established at the De-construction and Environment Engineering Center (CIDEN), is effective and productive. Estimates of costs and expenses are coherent, which makes the forecasts put together to finance the programme secure. CIDEN has carried out significant engineering work over the last six years, making it possible to apply for the administrative authorizations which have now been obtained or are in the process of being obtained. Technical specifications are prepared at an optimized level of detail according to a contractual policy adapted to the complexity of the operations and the sharing of risk with manufacturers. The ChoozA contractualization process has been launched and the first dismantling work has begun in the nuclear auxiliary part. The main Brennilis contract will be completed in mid- 2008 and dismantling works will restart after renewal of the decree which was cancelled in mid-2007. Treatment of sodium from Creys Malville is about to begin, leading to elimination of the sodium risk by 2013. The very low activity waste (TFA) and low to medium activity waste (FA-MA) removal chains are operational. The intermediate activity/long lived (MA-VL) waste will be stored in a facility which will be brought into operational service in 2012. The graphite storage center is due to open between 2017 and 2019

  3. Autocatalytic microtubule nucleation determines the size and mass of Xenopus laevis egg extract spindles.

    Science.gov (United States)

    Decker, Franziska; Oriola, David; Dalton, Benjamin; Brugués, Jan

    2018-01-11

    Regulation of size and growth is a fundamental problem in biology. A prominent example is the formation of the mitotic spindle, where protein concentration gradients around chromosomes are thought to regulate spindle growth by controlling microtubule nucleation. Previous evidence suggests that microtubules nucleate throughout the spindle structure. However, the mechanisms underlying microtubule nucleation and its spatial regulation are still unclear. Here, we developed an assay based on laser ablation to directly probe microtubule nucleation events in Xenopus laevis egg extracts. Combining this method with theory and quantitative microscopy, we show that the size of a spindle is controlled by autocatalytic growth of microtubules, driven by microtubule-stimulated microtubule nucleation. The autocatalytic activity of this nucleation system is spatially regulated by the limiting amounts of active microtubule nucleators, which decrease with distance from the chromosomes. This mechanism provides an upper limit to spindle size even when resources are not limiting. © 2018, Decker et al.

  4. The engine of microtubule dynamics comes into focus.

    Science.gov (United States)

    Mitchison, T J

    2014-05-22

    In this issue, Alushin et al. report high-resolution structures of three states of the microtubule lattice: GTP-bound, which is stable to depolymerization; unstable GDP-bound; and stable Taxol and GDP-bound. By comparing these structures at near-atomic resolution, they are able to propose a detailed model for how GTP hydrolysis destabilizes the microtubule and thus powers dynamic instability and chromosome movement. Destabilization of cytoskeleton filaments by nucleotide hydrolysis is an important general principle in cell dynamics, and this work represents a major step forward on a problem with a long history. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Regulation of microtubule nucleation mediated by gamma-tubulin complexes

    Czech Academy of Sciences Publication Activity Database

    Sulimenko, Vadym; Hájková, Zuzana; Klebanovych, Anastasiya; Dráber, Pavel

    2017-01-01

    Roč. 254, č. 3 (2017), s. 1187-1199 ISSN 0033-183X R&D Projects: GA MŠk(CZ) LD13015 Institutional support: RVO:68378050 Keywords : mitotic spindle formation * ring complex * fission yeast * organizing centers * protein complex * golgi-complex * cell-cycle * pole body * augmin * centrosome * Centrosomes * Microtubule nucleation * Microtubule-organizing centers * Non-centrosomal nucleation sites * Spindle pole bodies * gamma-Tubulin complexes Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Cell biology Impact factor: 2.870, year: 2016

  6. S. pombe kinesins-8 promote both nucleation and catastrophe of microtubules.

    Directory of Open Access Journals (Sweden)

    Muriel Erent

    Full Text Available The kinesins-8 were originally thought to be microtubule depolymerases, but are now emerging as more versatile catalysts of microtubule dynamics. We show here that S. pombe Klp5-436 and Klp6-440 are non-processive plus-end-directed motors whose in vitro velocities on S. pombe microtubules at 7 and 23 nm s(-1 are too slow to keep pace with the growing tips of dynamic interphase microtubules in living S. pombe. In vitro, Klp5 and 6 dimers exhibit a hitherto-undescribed combination of strong enhancement of microtubule nucleation with no effect on growth rate or catastrophe frequency. By contrast in vivo, both Klp5 and Klp6 promote microtubule catastrophe at cell ends whilst Klp6 also increases the number of interphase microtubule arrays (IMAs. Our data support a model in which Klp5/6 bind tightly to free tubulin heterodimers, strongly promoting the nucleation of new microtubules, and then continue to land as a tubulin-motor complex on the tips of growing microtubules, with the motors then dissociating after a few seconds residence on the lattice. In vivo, we predict that only at cell ends, when growing microtubule tips become lodged and their growth slows down, will Klp5/6 motor activity succeed in tracking growing microtubule tips. This mechanism would allow Klp5/6 to detect the arrival of microtubule tips at cells ends and to amplify the intrinsic tendency for microtubules to catastrophise in compression at cell ends. Our evidence identifies Klp5 and 6 as spatial regulators of microtubule dynamics that enhance both microtubule nucleation at the cell centre and microtubule catastrophe at the cell ends.

  7. Method and jig for dismantling nuclear fuel assembly

    International Nuclear Information System (INIS)

    Urata, Megumi; Watahiki, Minoru.

    1989-01-01

    The object of the present inention is to extract a fuel element from a lower tie plate safely and at high efficiency by a remote control operation. That is, a forked top end of a lever of a dismantling jig is inserted between the tapered portion of a lower end plug and a lower tie plate. Then, a load is applied to the counter-lower end side of the lever by a motor. This exerts an elevating force to the fuel elements to easily release fixture between the lower end plug and the lower tie plate. Since the fuel can of fuel elements is not applied with a force by this mehtod, operation safety can be improved. (I.J.)

  8. Decontamination before dismantling a fast breeder reactor primary cooling system

    International Nuclear Information System (INIS)

    Costes, J.R.; Antoine, P.; Gauchon, J.P.

    1997-01-01

    The large-scale decontamination of FBR sodium loops is a novel task, as only a limited number of laboratory-scale results are available to date. The principal objective of this work is to develop a suitable decontamination procedure for application to the primary loops of the RAPSODIE fast breeder reactor as part of decommissioning to Stage 2. After disconnecting the piping from the main vessel, the pipes were treated by circulating chemical solutions and the vessels by spraying. The dose rate in the areas to be dismantled was divided by ten. A decontamination factor of about 300 was obtained, and should allow austenitic steel parts to be melted in special furnaces for unrestricted release. (author)

  9. The Dismantling of the Japanese Model in Consumer Electronics

    DEFF Research Database (Denmark)

    Frøslev Christensen, Jens; Holm Olesen, Michael; Kjær, Jonas

    This paper addresses an issue of great importance for the future organization of the consumerelectronics industry: the "battle" of control over component-based digitization. We are now witnessing the dismantling of the Japanese Model that has prevailed in consumer electronicsover the past 30 years....... Specialized and large-scale component suppliers have taken the lead inmost component-based innovations and have obtained increasingly powerful positions in thevalue chain of consumer electronics. This paper provides an in-depth study of the strategic andstructural ramifications of one such component...... technology. Aframework is developed to explain the reluctance of most of the large consumer electronicsgiants in developing/adopting this new technology.Key words: Consumer electronics, Industrial dynamics, Open InnovationJEL Codes: L6, L68, O32...

  10. Method and apparatus for dismantling and disposing of fuel assemblies

    International Nuclear Information System (INIS)

    Meuschke, R.E.; Schulties, J.R.

    1985-01-01

    This invention relates to apparatus and a method for dismantling, shearing, and compacting a fuel assembly frame skeleton. It uses an apparatus capable of hanging or being supported in the transfer canal of the spent fuel pit of the fuel handling building. This apparatus includes a bottom nozzle shear which is held under water to shear off the bottom nozzle and convey it to a scrap transfer bin. Then the remaining portion is brought to a skeleton compactor and shear, also held under water. The compacted skeleton is sheared into a number of smaller portions. After compacting and shearing, the individual portions are fed to the scrap transfer bin. The compacted and sheared skeleton assembly may be placed into a container that is adapted to hold four skeletons for off-site removal

  11. Decommissioning and Dismantling of the Floating Maintenance Base 'Lepse' - 13316

    International Nuclear Information System (INIS)

    Field, D.; Mizen, K.

    2013-01-01

    The Lepse was built in Russia in 1934 and commissioned as a dry cargo ship. In 1961 she was re-equipped for use as a nuclear service ship (NSS), specifically a floating maintenance base (FMB), to support the operation of the civilian nuclear fleet (ice-breakers) of the USSR. In 1988 Lepse was taken out of service and in 1990 she was re-classified as a 'berth connected ship', located at a berth near the port of Murmansk under the ownership of Federal State Unitary Enterprise (FSUE) Atomflot. Lepse has special storage facilities for spent nuclear fuel assemblies (SFA) that have been used to store several hundred SFAs for nearly 40 years. High and intermediate-level liquid radioactive waste (LRW) is also present in the spent nuclear fuel assembly storage channels, in special tanks and also in the SFA cooling circuit. Many of the SFAs stored in Lepse are classified as damaged and cannot be removed using standard procedures. The removal of the SFA and LRW from the Lepse storage facilities is a hazardous task and requires specially designed tools, equipment and an infrastructure in which these can be deployed safely. Lepse is a significant environmental hazard in the North West of Russia. Storing spent nuclear fuel and high-level liquid radioactive waste on board Lepse in the current conditions is not acceptable with respect to Russian Federation health, safety and environmental standards and with international best practice. The approved concept design for the removal of the SFA and LRW and dismantling of Lepse requires that the ship be transported to Nerpa shipyard where specialist infrastructure will be constructed and equipment installed. One of the main complexities of the Project lies within the number of interested stakeholders involved in the Project. The Lepse project has been high focus on the international stage for many years with previous international efforts failing to make significant progress towards the objective of decommissioning Lepse. The Northern

  12. Outsourcing and "dismantling" of steady jobs at hospitals

    Directory of Open Access Journals (Sweden)

    Helton Saragor de Souza

    2016-04-01

    Full Text Available Abstract OBJECTIVE To relate hospitals' organizational structure as the core of a web of outsourced services and flexible employment bonds among healthcare professionals in the context of finance capitalism, analyzing work arrangements based mainly on the type of employment bond. METHOD Qualitative research through ethnography, interviews, data analysis, and case studies. The case studies were concentrated in 3 hospitals located in the São Paulo metropolitan region under different management types: public administration; outsourced administration via a healthcare social organization (HSO; and private administration. RESULTS This study highlights a trend in outsourcing, dismantling of steady jobs, and shaping working relations asymmetrically in terms of healthcare professions. CONCLUSION These aspects are characteristic of contemporary capitalism and post-Fordist work organization. In this context, the state under sponsorship cripples the very existence of an effective human resources policy, creating a favorable environment for outsourcing and flexibility of employment bonds among healthcare workers.

  13. The Dismantling Project for the Large Electron Positron (LEP) Collider

    CERN Document Server

    Poole, John

    2002-01-01

    The LEP accelerator was installed in a circular tunnel 27 km in length with nine access points distributed around the circumference in the countryside and villages which surround CERN's sites. The dismantling project involved the removal in less than 15 months of around 29000 tonnes of equipment from the accelerator itself and a further 10000 tonnes from the four experiments - all of which were located at an average depth of 100 m below ground level. There was no contamination risk in the project and less than 3% of the materials removed were classified as radioactive. However, the materials which were classified as radioactive have to be temporarily stored and they consume considerable resources. The major difficulties for the project were in the establishment of the theoretical radiological zoning, implementation of the traceability systems and making appropriate radiation measurements to confirm the zoning. The absence of detailed guidelines from the French authorities, having no threshold levels for relea...

  14. Large components dismantlement flow chart in the United States

    International Nuclear Information System (INIS)

    Szilagyi, Andrew

    2012-01-01

    The beginning steps are identical for large or regular components. The starting point of this flowchart assumes that it has already been determined the component has been categorized as waste. The first step is to make sure that all components are handled safely, that ALARA is followed, that any security concerns are managed, and that the dismantlement cost or any other cost is constantly reviewed. After this, the process knowledge and acceptable knowledge should be reviewed; this will help in the following step which is characterization with non-destructive assay. At this point, the project manager is presented with the first three alternatives which will determine the path to follow: Low level waste (LLW) disposal flowchart, part 1 to 3 , Transuranic waste (TRU) disposal flowchart, part 1 and 2 , or High level waste (HLW) disposal flowchart

  15. Mock-up-CZ: dismantling of the experiment - Geotechnical results

    International Nuclear Information System (INIS)

    Svoboda, J.; Vasicek, R.

    2010-01-01

    Document available in extended abstract form only. The issue of the disposal of radioactive waste is one of the most pressing challenges of our age, for which, in most countries, the deep repository concept is generally considered to be the most suitable final solution. In order to make such a repository both safe and reliable, intensive research is underway worldwide. The construction of physical models is one approach to the study of the engineered barriers for deep geological repositories; one such experiment, Mock-Up-CZ, has been performed at the Centre of Experimental Geotechnics, CTU in Prague. The Mock-Up-CZ experiment simulated the vertical placement of a container with radioactive waste, an approach that is in line with the Swedish KBS-3 system. The physical model consisted of a barrier made up of bentonite blocks, powdered bentonite backfill, a heater and hydration and monitoring systems. The whole experiment was enclosed in a cylindrical box, whose construction was able to withstand high pressure due to bentonite swelling. A number of sensors (monitoring changes in temperature, pressure and moisture) were placed inside the bentonite barrier. The basic material used in the experiment consisted of a mixture of Czech bentonite from the Rokle deposit (85%), quartz sand (10%) and graphite (5%). The first phase of the experiment commenced on 7 May 2002, during which the heater was switched on, with no water input. After 6 months the second phase commenced in which water was introduced through the hydration system. This phase ended on 2nd January 2006 when the heater was switched off. After allowing time for cooling, the dismantling phase commenced (30 January 2006). After a further one and a half months (17 March 2006) the dismantling of the experimental vessel was completed. Post-decommissioning analysis continued until the end of 2007. Dismantling and post-decommissioning analysis were carried out according to a very detailed plan which included not only

  16. Advanced Planning Concepts in the Closed-Loop Container Network of ARN

    NARCIS (Netherlands)

    Le Blanc, H.M.; van Krieken, M.G.C.; Krikke, H.R.; Fleuren, H.A.

    2004-01-01

    In this paper we discuss a real-life case study in the optimization of the logistics network for the collection of containers from end-of-life vehicle dismantlers in the Netherlands.Advanced planning concepts like dynamic assignment of dismantlers to logistic service providers are analyzed by a

  17. Cutting techniques for facilities dismantling in decommissioning projects

    International Nuclear Information System (INIS)

    Lainetti, Paulo E.O.

    2011-01-01

    Fuel cycle related activities were accomplished in IPEN-CNEN/SP in laboratory and pilot plant scale and most facilities were built in the 70-80 years. Nevertheless, radical changes of the Brazilian nuclear policy in the beginning of 90's determined the interruption of several fuel cycle activities and facilities shutdown. Some laboratory and pilot plant decommissioning activities have been performed in IPEN in the last years. During the operational activities in the decommissioning of old nuclear fuel cycle facilities, the personnel involved in the task had to face several problems. In old facilities, the need of large components dismantling and material removal use to present some difficulties, such as lack of available and near electricity supply. Besides this, the spread out of the superficial contamination in the form of dust or aerosols and the exposure of workers should be as much as possible avoided. Then, the selection and availability of suitable tools for the task, mainly those employed for cutting and segmentation of different materials is of significant importance. Slight hand tools, mainly those powered by rechargeable batteries, facilitate the work, especially in areas where the access is difficult. Based on the experience in the dismantling of some old nuclear facilities of IPEN-CNEN/SP, some tools that would have facilitated the operations were identified and their availability could have improved the quality and efficiency of different individual tasks. In this paper different cutting problems and techniques, as well as some available commercial hand tools, are presented as suggestion for future activities. (author)

  18. Dietary flavonoid fisetin binds to β-tubulin and disrupts microtubule dynamics in prostate cancer cells

    OpenAIRE

    Mukhtar, Eiman; Adhami, Vaqar Mustafa; Sechi, Mario; Mukhtar, Hasan

    2015-01-01

    Microtubule targeting based therapies have revolutionized cancer treatment; however, resistance and side effects remain a major limitation. Therefore, novel strategies that can overcome these limitations are urgently needed. We made a novel discovery that fisetin, a hydroxyflavone, is a microtubule stabilizing agent. Fisetin binds to tubulin and stabilizes microtubules with binding characteristics far superior than paclitaxel. Surface plasmon resonance and computational docking studies sugges...

  19. Microtubule protein ADP-ribosylation in vitro leads to assembly inhibition and rapid depolymerization

    Energy Technology Data Exchange (ETDEWEB)

    Scaife, R.M. (Fred Hutchinson Cancer Research Center, Seattle, WA (United States)); Wilson, L. (Univ. of California, Santa Barbara (United States)); Purich, D.L. (Univ. of Florida, Gainesville (United States))

    1992-01-14

    Bovine brain microtubule protein, containing both tubulin and microtubule-associated proteins, undergoes ADP-ribosylation in the presence of ({sup 14}C)NAD{sup +} and a turkey erythrocyte mono-ADP-ribosyltransferase in vitro. The modification reaction could be demonstrated in crude brain tissue extracts where selective ADP-ribosylation of both the {alpha} and {beta} chains of tubulin and of the high molecular weight microtubule-associated protein MAP-2 occurred. In experiments with purified microtubule protein, tubulin dimer, the high molecular weight microtubule-associated protein MAP-2, and another high molecular weight microtubule-associated protein which may be a MAP-1 species were heavily labeled. Tubulin and MAP-2 incorporated ({sup 14}C)ADP-ribose to an average extent of approximately 2.4 and 30 mol of ADP-ribose/mol of protein, respectively. Assembly of microtubule protein into microtubules in vitro was inhibited by ADP-ribosylation, and incubation of assembled steady-state microtubules with ADP-ribosyltransferase and NAD{sup +} resulted in rapid depolymerization of the microtubules. Thus, the eukaryotic enzyme can ADP-ribosylate tubulin and microtubule-associated proteins to much greater extents than previously observed with cholera and pertussis toxins, and the modification can significantly modulate microtubule assembly and disassembly.

  20. Optimized phases for reactor dismantling – an efficient and sustainable concept

    International Nuclear Information System (INIS)

    Krüger, S.; Winter, J.

    2013-01-01

    D&D projects are driven by costs, to implement an optimization process from the very beginning is key. Optimized strategy and sequencing of the dismantling (hot to cold) will provide serious economical savings . Larger dismantling packages will reduce interfaces and ease the coordination efforts on site. Early usage of mobile systems will ease the large-scale release for dismantling Social transition has to be addressed with priority and to be planned at an early phase in the D&D planning Concept, Planning & Project Management will influence the success of the project much more than the used technique

  1. Clearance of radioactive materials during reactor dismantling. Permanent enclosure instead of demolition and renaturation?

    International Nuclear Information System (INIS)

    2016-01-01

    During reactor dismantling besides high-level radioactive wastes a large amount of low-level contaminated steel and concrete has to be disposed. In case that radioactivity falls below defined dose limits (10 micro Sv/person and year) these materials may be disposed in domestic waste landfill or in municipal incineration facilities. The issue is discussed in detail including the fact that many power plants are dismantled at the same time so that the contaminated materials might accumulate. Another issue is the occupational safety of contract workers during dismantling. The permanent enclosure could avoid this environmental contamination of decommissioned power plants might also be less expensive.

  2. Importance of low-level radioactive wastes in dismantling strategy in CEA (FRANCE)

    International Nuclear Information System (INIS)

    Lafaille, C.

    1991-01-01

    This paper describes the advance used in C.E.A. to realize dismantling operations in the best technical and economical conditions. Particularly, for low-level radioactive waste management CEA's advance defines, first, the final destination of dismantling materials: - recycling in public lands for level activity inferior to 1 Bq/g; directly or after transformation (melting, calcination, extrusion) - storage in a ground disposal, after compacting, encapsulation or drumming. Two examples are given: - Marcoule G2 - G3 reactor dismantling - Gaseous diffusion plants demolition (COGEMA Pierrelatte)

  3. NucLab Marcoule. A laboratory facility dedicated to support dismantling operations

    International Nuclear Information System (INIS)

    Dugne, O.; Houssin, A.; Pierre, D.; Bec-Espitalier, L.

    2013-06-01

    Formerly dedicated to plutonium production support, NucLab was renovated to perform a wide range of analyses for dismantling, plant operation and process development activities mainly on Marcoule site but also outside (Veurey, Fontenay aux Roses). The Laboratory is under a CEA AREVA partnership as a CEA entity operated by AREVA employees. It provides services to several industrial operators (nuclear process and power plant) in the fields of analytical chemistry, radioactivity measurements, in situ nuclear measurements, decontamination processes and industrial chemistry processes, waste treatments to meet the following analysis requirements. NucLab today is able to support research, production and dismantling activities in all part of dismantling operations. (authors)

  4. System approach as a tool for optimization of the dismantling technological process of NPP decommissioning

    International Nuclear Information System (INIS)

    Bylkin, B.K.; Shpitser, V.Ya.

    1994-01-01

    The concept of NPP unit decommissioning has been considered. Special attention was paid to the stage of dismantling of NPP unit equipment. Employment of systematic approach as a tool for optimization of dismantling processes permits formalizing manipulations with certified indices of quality and it permits an objective assessment of the dismantling technology level attained during designing as compared with the basic one. It seems appropriate to develop a basic project of NPP unit decommissioning as a technical means of planning, predicting and evaluating ecological and social aftereffects

  5. Report of working group for technical standard of cutting and melting works in Glovebox dismantling

    International Nuclear Information System (INIS)

    Asazuma, Shinichiroh; Takeda, Shinsoh; Tajima, Shoichi

    2004-11-01

    In order to prevent spread of contamination, glovebox dismantling activity is usually performed in a confined enclosure with personal radioactive protective equipment. Since large potion of these materials is made of vinyl acetate, there exist potential risks of fire, damage and injury to the environment and workers during the dismantling (cutting or melting) operation. It is therefore important to establish standard for proper use of equipment and hazard controls in such a specific environment. Working Group composed of Tokai Works and Oarai Works has examined and developed the operational standard for cutting work in glovebox dismantlement. The result is reflected to the Tokai Works Safety Operational Standard. (author)

  6. How biological microtubules may avoid decoherence

    International Nuclear Information System (INIS)

    Hameroff, S.

    2005-01-01

    Full text: Entangled superpositions persisting for hundreds of milliseconds in protein assemblies such as microtubules (MTs) are proposed in biological functions, e.g. quantum computation relevant to consciousness in the Penrose-Hameroff 'Orch OR' model. Cylindrical polymers of the protein tubulin, MTs organize cell activities. The obvious question is how biological quantum states could avoid decoherence, e.g. in the brain at 37.6 degrees centigrade. Screening/sheelding: tubulin protein states/functions are governed by van der Waals London forces, quantum interactions among clouds of delocalizable electrons in nonpolar 'hydrophobic' intra-protein pockets screened from external van der Waals thermal interactions. Such pockets include amino acid resonance structures benzene and indole rings. (Anesthetic gases erase consciousness solely by interfering with London forces in hydrophobic pockets in various brain proteins). Hence tubulin states may act as superpositioned qubits also shielded at the MT level by counter-ion Debye plasma layers (due to charged C-termini tails on tubulin) and by water-ordering actin gels which embed MTs in a quasi-solid. Biological systems may also exploit thermodynamic gradients to give extremely low effective temperatures. Decoherence free subspaces: paradoxically, a system coupled strongly to its environment through certain degrees of freedom can effectively 'freeze' other degrees of freedom (quantum Zeno effect), enabling coherent superpositions and entanglement to persist. Metabolic energy supplied to MT collective dynamics (e.g. Froehlich coherence) can cause Bose-Einstein condenzation and counter decoherence as lasers avoid decoherence at room temperature. Topological quantum error correction: MT lattice structure reveals various helical winding paths through adjacent tubulins which follow the Fibonacci series. Propagation/interactions of quasi-particles along these paths may process information. As proposed by Kitaev (1997), various

  7. Prion protein inhibits microtubule assembly by inducing tubulin oligomerization

    International Nuclear Information System (INIS)

    Nieznanski, Krzysztof; Podlubnaya, Zoya A.; Nieznanska, Hanna

    2006-01-01

    A growing body of evidence points to an association of prion protein (PrP) with microtubular cytoskeleton. Recently, direct binding of PrP to tubulin has also been found. In this work, using standard light scattering measurements, sedimentation experiments, and electron microscopy, we show for First time the effect of a direct interaction between these proteins on tubulin polymerization. We demonstrate that full-length recombinant PrP induces a rapid increase in the turbidity of tubulin diluted below the critical concentration for microtubule assembly. This effect requires magnesium ions and is weakened by NaCl. Moreover, the PrP-induced light scattering structures of tubulin are cold-stable. In preparations of diluted tubulin incubated with PrP, electron microscopy revealed the presence of ∼50 nm disc-shaped structures not reported so far. These unique tubulin oligomers may form large aggregates. The effect of PrP is more pronounced under the conditions promoting microtubule formation. In these tubulin samples, PrP induces formation of the above oligomers associated with short protofilaments and sheets of protofilaments into aggregates. Noticeably, this is accompanied by a significant reduction of the number and length of microtubules. Hence, we postulate that prion protein may act as an inhibitor of microtubule assembly by inducing formation of stable tubulin oligomers

  8. EWSR1 regulates mitosis by dynamically influencing microtubule acetylation.

    Science.gov (United States)

    Wang, Yi-Long; Chen, Hui; Zhan, Yi-Qun; Yin, Rong-Hua; Li, Chang-Yan; Ge, Chang-Hui; Yu, Miao; Yang, Xiao-Ming

    2016-08-17

    EWSR1, participating in transcription and splicing, has been identified as a translocation partner for various transcription factors, resulting in translocation, which in turn plays crucial roles in tumorigenesis. Recent studies have investigated the role of EWSR1 in mitosis. However, the effect of EWSR1 on mitosis is poorly understood. Here, we observed that depletion of EWSR1 resulted in cell cycle arrest in the mitotic phase, mainly due to an increase in the time from nuclear envelope breakdown to metaphase, resulting in a high percentage of unaligned chromosomes and multipolar spindles. We also demonstrated that EWSR1 is a spindle-associated protein that interacts with α-tubulin during mitosis. EWSR1 depletion increased the cold-sensitivity of spindle microtubules, and decreased the rate of spindle assembly. EWSR1 regulated the level of microtubule acetylation in the mitotic spindle; microtubule acetylation was rescued in EWSR1-depleted mitotic cells following suppression of HDAC6 activity by its specific inhibitor or siRNA treatment. In summary, these results suggest that EWSR1 regulates the acetylation of microtubules in a cell cycle-dependent manner through its dynamic location on spindle MTs, and may be a novel regulator for mitosis progress independent of its translocation.

  9. Neuronal microtubule organization: from minus end to plus end

    NARCIS (Netherlands)

    Yau, K.W.

    2016-01-01

    Neurons are highly polarized cells consisting of a dendritic part and axonal part. Dendrites receive signals from other cells while axons transmit signals to other cells. In this thesis, mostly hippocampal neurons from rat embryos are used to study fundamental aspects of the microtubule organization

  10. Microtubules in cell migration, morphogenesis and metabolism: Making the connections

    NARCIS (Netherlands)

    Noordstra, I.

    2017-01-01

    Cell polarity refers to a fundamental property of eukaryotic cells, in which cellular components and structures are organized in an asymmetric fashion. In order to control their polarity, cells make use of microtubules, hollow polymers that extend throughout the cytoplasm. Due to the asymmetry of

  11. Optical Tweezers-Based Measurements of Forces and Dynamics at Microtubule Ends.

    Science.gov (United States)

    Baclayon, Marian; Kalisch, Svenja-Marei; Hendel, Ed; Laan, Liedewij; Husson, Julien; Munteanu, E Laura; Dogterom, Marileen

    2017-01-01

    Microtubules are dynamic cytoskeletal polymers that polymerize and depolymerize while interacting with different proteins and structures within the cell. The highly regulated dynamic properties as well as the pushing and pulling forces generated by dynamic microtubule ends play important roles in processes such as in cell division. For instance, microtubule end-binding proteins are known to affect dramatically the dynamic properties of microtubules, and cortical dyneins are known to mediate pulling forces on microtubule ends. We discuss in this chapter our efforts to reconstitute these systems in vitro and mimic their interactions with structures within the cell using micro-fabricated barriers. Using an optical tweezers setup, we investigate the dynamics and forces of microtubules growing against functionalized barriers in the absence and presence of end-binding proteins and barrier-attached motor proteins. This setup allows high-speed as well as nanometer and piconewton resolution measurements on dynamic microtubules.

  12. On evaluation of assessments of accruals of future dismantling costs

    Energy Technology Data Exchange (ETDEWEB)

    Labor, Bea [B D Projects 2013, Gdansk (Poland); Lindskog, Staffan [Swedish Radiation Safety Authority, Solna (Sweden)

    2013-07-01

    A major prerequisite in order for civilian commercial nuclear energy production to qualify as sustainable energy production is that systems for the management of the nuclear waste legacy are in operation. These waste types are present in a range from very low short lived waste (VLLW) to long lived high level waste (HLW) (including the used nuclear fuel). The second prerequisite is that financial responsibilities or other constraints must not be passed on to coming generations. The first condition for qualification corresponds to the Polluters Pays Principle (PPP) which demands that the responsibility for the waste management rests solely with the polluter. The second qualification corresponds to the principle of fairness between generations and thus concerns the appropriate distribution of responsibilities between the generations. It is important to note that these two conditions must be met simultaneously, and that compliance with both is a necessary prerequisite in order for commercial use of nuclear power to qualify as a semi-sustainable energy source. Financial and technical planning for dismantling and decommissioning of nuclear installations cannot be regarded as successful unless it rests upon a distinctive way to describe and explain the well-founded values of different groups of stakeholders. This cumbersome task can be underpinned by transparent and easy to grasp models for calculation and estimation of future environmental liabilities. It essential that a systematic classification is done of all types of costs and that an effort is done to evaluate the precision level in the cost estimates. In this paper, a systematic and transparent way to develop a parametric approach that rest upon basic accounting standards is combined with data about younger stakeholder's values towards decommissioning and dismantling of nuclear installation. The former entity rests upon theoretical and practical methods from business administration, whilst the latter is based

  13. On evaluation of assessments of accruals of future dismantling costs

    International Nuclear Information System (INIS)

    Labor, Bea; Lindskog, Staffan

    2013-01-01

    A major prerequisite in order for civilian commercial nuclear energy production to qualify as sustainable energy production is that systems for the management of the nuclear waste legacy are in operation. These waste types are present in a range from very low short lived waste (VLLW) to long lived high level waste (HLW) (including the used nuclear fuel). The second prerequisite is that financial responsibilities or other constraints must not be passed on to coming generations. The first condition for qualification corresponds to the Polluters Pays Principle (PPP) which demands that the responsibility for the waste management rests solely with the polluter. The second qualification corresponds to the principle of fairness between generations and thus concerns the appropriate distribution of responsibilities between the generations. It is important to note that these two conditions must be met simultaneously, and that compliance with both is a necessary prerequisite in order for commercial use of nuclear power to qualify as a semi-sustainable energy source. Financial and technical planning for dismantling and decommissioning of nuclear installations cannot be regarded as successful unless it rests upon a distinctive way to describe and explain the well-founded values of different groups of stakeholders. This cumbersome task can be underpinned by transparent and easy to grasp models for calculation and estimation of future environmental liabilities. It essential that a systematic classification is done of all types of costs and that an effort is done to evaluate the precision level in the cost estimates. In this paper, a systematic and transparent way to develop a parametric approach that rest upon basic accounting standards is combined with data about younger stakeholder's values towards decommissioning and dismantling of nuclear installation. The former entity rests upon theoretical and practical methods from business administration, whilst the latter is based

  14. Present status of refining and conversion facility dismantling. Progress in latter half of 2010FY

    International Nuclear Information System (INIS)

    Kado, Kazumi; Sugitsue, Noritake; Morimoto, Yasuyuki; Ikegami, Sohei; Tanaka, Yoshio; Takahashi, Nobuo; Tokuyasu, Takashi

    2011-09-01

    The Refining and Conversion Facility located in the Ningyo-toge Environmental Engineering Center had the natural uranium conversion process and reprocessed uranium conversion process. The construction of this facility was started in 1979 and completed in October 1981. Dismantling of equipments in radiation controlled area of this facility was started from 2008. Equipments in radiation controlled area (excluding ventilating equipment and liquid waste treatment equipment) will be dismantled by the 2011 fiscal year, and ventilating equipment and liquid waste treatment equipment will be dismantled by the 2014 fiscal year. This report describes the master plan of this decommissioning and shows as the progress in latter half year of 2010FY, the actual time schedule, the method of decommissioning, the decommissioning progress appearance with photographs, work rates of each room / each worker class, and the quantity of dismantled materials and secondary wastes. (author)

  15. LEAR, shown here dismantled, will live to see another golden era as LEIR starting in 2005.

    CERN Multimedia

    Maximilien Brice

    2004-01-01

    The LEAR (Low Energy Antiproton Ring) experiment has now been dismantled. Only the dipoles remain for use in the future LEIR (Low Energy Ion Ring) experiment, the new ring which will supply lead ions to the LHC experiments.

  16. Deliberated opinion of the Environment Authority concerning the dismantling of the Ulysse reactor (CEA Saclay)

    International Nuclear Information System (INIS)

    2010-01-01

    As the Ulysse reactor of Saclay is about to be dismantled, this report discusses the content of a request made by the CEA to definitely stop and dismantle this reactor. After having recalled the origin of this dismantling project and its regulatory framework, it describes the actual works which are planned, and outlines the main challenges to be faced. It discusses the content of the environmental report or impact study, notably the analysis of the initial condition, the analysis of direct and indirect effects of the project on the environment and health, and of the envisaged measures (waste management, liquid and gaseous effluent management, risk management, radiological exposure of workers in charge of this dismantling, and transports). Recommendations are formulated for a rewriting of the provided documents

  17. Cutting Method of the CAD model of the Nuclear facility for Dismantling Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ikjune; Choi, ByungSeon; Hyun, Dongjun; Jeong, KwanSeong; Kim, GeunHo; Lee, Jonghwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Current methods for process simulation cannot simulate the cutting operation flexibly. As is, to simulate a cutting operation, user needs to prepare the result models of cutting operation based on pre-define cutting path, depth and thickness with respect to a dismantle scenario in advance. And those preparations should be built again as scenario changes. To be, user can change parameters and scenarios dynamically within a simulation configuration process so that the user saves time and efforts to simulate cutting operations. This study presents the methodology of cutting operation which can be applied to all the procedure in the simulation of dismantling of nuclear facilities. We developed the cutting simulation module for cutting operation in the dismantling of the nuclear facilities based on proposed cutting methodology. We defined the requirement of model cutting methodology based on the requirement of the dismantling of nuclear facilities. And we implemented cutting simulation module based on API of the commercial CAD system.

  18. Sites with nuclear facilities in the state of dismantling and their future from the public perspective

    International Nuclear Information System (INIS)

    Kretz, Simon Philipp

    2015-01-01

    The thesis on the public perspective at sites of nuclear facility dismantling covers the following issues: the change of German energy landscapes under social and political points of view, theoretical frame of the work, combination of empirical studies and the theoretical approaches in a space concept, action model and hypotheses on the situation and development in communities with nuclear facilities in the state of dismantling, description of the interviewees, and the empirical results of the interviews.

  19. Management system information of characterization of the dismantling project of Jose Cabrera

    International Nuclear Information System (INIS)

    Gimeno Blesa, M. E.; Martin Palomo, N.; Gomez Rodriguez, C. A.

    2011-01-01

    In the proposed dismantling and decommissioning of the Jose Cabrera NPP is designed and implemented a database of physical and radiological inventory, which provides a powerful tool to optimize the storage, monitoring and control of the characterization data. The database is a useful and reliable management system characterization information that facilitates access and information processing, and ensures their integrity and traceability along of the dismantling project.

  20. Parameters of Dismantling Techniques Related to Costs for Decommissioning of Nuclear Facilities

    International Nuclear Information System (INIS)

    Jeong, Kwanseong; Moon, Jeikwon; Choi, Byungseon

    2012-01-01

    Reliable cost estimating is one of the most important elements of decommissioning operation. Reliable cost estimating is one of the most important elements of decommissioning planning. Alternative technologies may be evaluated and compared on their efficiency and effectiveness, and measured against a baseline cost as to the feasibility and benefit derived from the technology. This principle ensures that the cost consideration is economically sound and practical for funding. This paper provides a list with basic review of cutting and dismantling techniques, including some typical characteristics if available, as well as aspects of implementation, parameters of cutting and dismantling techniques in decommissioning costing. This paper gives an overview of the principles of the unit factor approach and its implementation in costing in relation to dismantling activities. In general, proper evaluation of decommissioning costs is important for following issues and relevant measures for achieving the listed aspects are: · Selection of a decommissioning strategy and activities: several decommissioning options should be evaluated: · Support to a cost-benefit analysis to ensure that the principle of optimization and reasonably practicable measures are applied: the extent of evaluated decommissioning options should cover all possible scenarios for dismantling activities; · Estimate of required financial resources for the selected strategy: the selected option should involve the dismantling activities in a structure and extent relevant to real procedure of dismantling activities; · Preparation of the project schedule, workforce requirements and phased funding needs: dismantling activities should be structured according to the tasks of the decommissioning schedule; · Definition of measures for proper management and maintenance of resources for safe and timely decommissioning: the time distribution and safety related parameters of dismantling activities should be known

  1. The nucleation of microtubules in Aspergillus nidulans germlings

    Directory of Open Access Journals (Sweden)

    Cristina de Andrade-Monteiro

    1999-09-01

    Full Text Available Microtubules are filaments composed of dimers of alpha- and beta-tubulins, which have a variety of functions in living cells. In fungi, the spindle pole bodies usually have been considered to be microtubule-organizing centers. We used the antimicrotubule drug Benomyl in block/release experiments to depolymerize and repolymerize microtubules in Aspergillus nidulans germlings to learn more about the microtubule nucleation process in this filamentous fungus. Twenty seconds after release from Benomyl short microtubules were formed from several bright (immunofluorescent dots distributed along the germlings, suggesting that microtubule nucleation is randomly distributed in A. nidulans germlings. Since nuclear movement is dependent on microtubules in A. nidulans we analyzed whether mutants defective in nuclear distribution along the growing hyphae (nud mutants have some obvious microtubule defect. Cytoplasmic, astral and spindle microtubules were present and appeared to be normal in all nud mutants. However, significant changes in the percentage of short versus long mitotic spindles were observed in nud mutants. This suggests that some of the nuclei of nud mutants do not reach the late stage of cell division at normal temperatures.Microtúbulos são filamentos compostos por dímeros das tubulinas a e b e têm uma variedade de funções nas células vivas. Em fungos, os corpúsculos polares dos fusos são geralmente considerados os centros organizadores dos microtúbulos. Com o objetivo de contribuir para uma melhor compreensão dos processos de nucleação dos microtúbulos no fungo filamentoso A. nidulans, nós utilizamos a droga antimicrotúbulo Benomil em experimentos de bloqueio e liberação para depolimerizar e repolimerizar os microtúbulos. Após 20 segundos de reincubação em meio sem Benomil, pequenos microtúbulos foram formados a partir de pontos distribuídos pela célula, sugerindo que os pontos de nucleação de microtúbulos s

  2. Development of the graphic design and control system based on a graphic simulator for the spent fuel dismantling equipment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. Y.; Kim, S. H.; Song, T. G.; Yoon, J. S

    2000-06-01

    In this study, the graphic design system is developed for designing the spent fuel rod consolidation and the dismantling processes. This system is used throughout the design stages from the conceptual design to the motion analysis. Also, the real-time control system of the rod extracting equipment is developed. This system utilizes the graphic simulator which simulates the motion of the equipment in real time by synchronously connecting the control PC with the graphic server through the TCP/IP network. The developed system is expected to be used as an effective tool in designing the process equipment for the spent fuel management. And the real-time graphic control system can be effectively used to enhance the reliability and safety of the spent fuel handling process by providing the remote monitoring function of the process.

  3. Development of the graphic design and control system based on a graphic simulator for the spent fuel dismantling equipment

    International Nuclear Information System (INIS)

    Lee, J. Y.; Kim, S. H.; Song, T. G.; Yoon, J. S.

    2000-06-01

    In this study, the graphic design system is developed for designing the spent fuel rod consolidation and the dismantling processes. This system is used throughout the design stages from the conceptual design to the motion analysis. Also, the real-time control system of the rod extracting equipment is developed. This system utilizes the graphic simulator which simulates the motion of the equipment in real time by synchronously connecting the control PC with the graphic server through the TCP/IP network. The developed system is expected to be used as an effective tool in designing the process equipment for the spent fuel management. And the real-time graphic control system can be effectively used to enhance the reliability and safety of the spent fuel handling process by providing the remote monitoring function of the process

  4. Method of processing dismantled products of radiation-contaminated equipments and transportation container therefor

    International Nuclear Information System (INIS)

    Komura, Shiro; Heki, Hideaki.

    1991-01-01

    In a method of decontaminating dismantled products of radiation-contaminated equipments removed at nuclear power facilities and classifying the dismantled products depending on their remaining radioactivity levels measured at a processing facility, the dismantled products are contained in a transportation container, to which decontamination liquids are injected and they are transferred to the processing facility. The decontaminated liquid wastes are drained from the transportation container, the dismantled products are washed while being contained in the transportation container as they are. Then, they are transferred to a step for measuring their remaining radioactivity level. This can shorten the time from the containment of the dismantled products to the transportation container to the completion of the decontamination, to improve the efficiency for the decontamination processing. Further, by separately containing the dismantled products on every kind of materials to respective containers, the processing time can be appropriately controlled respectively even if the dissolving efficiency to the decontamination liquids is different depending on the materials. (T.M.)

  5. Evaluation of decontamination during dismantling of plutonium-contaminated glove boxes

    International Nuclear Information System (INIS)

    Kinugasa, Manabu; Taguchi, Seigi; Ohzeki, Satoru; Inoue, Yoshiaki; Kashima, Sadamitsu

    1981-01-01

    The dismantling work of plutonium-contaminated glove boxes was carried out. These glove boxes had been used for the R and D of plutonium-uranium mixed oxide fuel for 15 years. The work was carried out in a pressure-controlled greenhouse, and the contamination of air in the greenhouse was monitored continuously. In order to reduce the contamination of air during dismantling, the decontamination and fixation of loose contaminants on the surfaces of glove boxes were very important. The correlation between decontamination and the contamination of air regarding dismantling is reported in this paper. The surface contamination density of the glove boxes was measured utilizing the smear method before and after the decontamination, and the decontamination effects were estimated. The contamination of air during dismantling was continuously measured with a plutonium dust monitor. It was found that loose contamination exponentially decreased by the decontamination process. When the so-called wet glove boxes, which contained wet recovery and waste disposal apparatus, were dismantled, the contamination of air did not exceed 500 (MPC) a. However, the contamination of air exceeded 500 (MPC) a several times in the present work of dismantling the so-called dry glove boxes which had been used for the fabrication of plutonium-uranium mixed oxide pellets. (Kato, T.)

  6. DIRECT DISMANTLING OF REPROCESSING PLANT CELLS THE EUREX PLANT EXPERIENCEe2d12c

    International Nuclear Information System (INIS)

    Gili, M.; Troiani, F.; Risoluti, P.

    2003-01-01

    After finishing the reprocessing campaigns in 1970-1983, the EUREX pilot reprocessing plant of ENEA Saluggia Research Center started into a new phase, aiming to materials and irradiated fuel systemation and radioactive wastes conditioning. In 1997 the project ''CORA'' for a vitrification plant for the high and intermediate liquid radioactive wastes started. The ''CORA'' plant will be hosted in some dismantled cells of the EUREX plant, reusing many of the EUREX plant auxiliary systems, duly refurbished, saving money and construction time and avoiding a new nuclear building in the site. Two of the cells that will be reused were part of the EUREX chemical process (solvent recovery and 2nd extraction cycle) and the components were obviously internally contaminated. In 2000 the direct (hands-on) dismantling of one of them started and has been completed in summer 2002; the second one will be dismantled in the next year and then the ''CORA'' plant will be assembled inside the cells. Special care w as taken to avoid spread of contamination in the cells, where ''CORA'' installation activities will start in the next years, during the dismantling process The analysis of data and results collected during the dismantling of the first cell shows that direct dismantling can be achieved with careful choice of tools, procedures and techniques, to reduce volumes of wastes to be disposed and radiological burden

  7. The Blue Lady Case and the International Issue of Ship Dismantling - Comment

    Directory of Open Access Journals (Sweden)

    Florent Pelsy

    2008-09-01

    Full Text Available This paper focuses on the decision of the Supreme Court of India to allow the dismantling of the Blue Lady (ex France in Alang. The first part underlines that the Supreme Court of India is prioritising the commercial interest of the dismantling companies over the social and environmental concerns of the workers and the communities living in Alang. It argues that such decision goes against its 2003 judgement on ship-dismantling. It then demonstrates that the Supreme Court of India is distorting the concept of sustainable development. The second part analyses the Blue Lady case from an international perspective since most of the ships that are dismantled in India come from developed countries. It provides an overview of the Basel Convention on ship dismantling issues and a study of the Clemenceau case before the French Conseil d'Etat. It then concludes that a better control of end-of-life ships in OECD countries and a new international convention on ship-dismantling would be necessary in order to prevent environmental and social disasters in Alang.

  8. Dismantling, conditioning and repatriation of disused sealed radioactive sources

    International Nuclear Information System (INIS)

    Aguilar, S.L.; Miranda, C.A.; Saire, A.E.; Ontiveros, G.P.

    2015-01-01

    In Bolivia sealed radioactive sources for medical, industrial and research applications are used; radioactive sources containing a wide range of radionuclides and have different levels of activity and half-lives, they generated a problem when they stop being used. At the end of its useful life these sources are considered obsolete. However, residual levels of radioactivity, which have these sources can be high constituting a potential hazard to personnel and applies to those who benefit from its use and the general public. The aim of this work has been focused mainly on safety issues in the safe handling and management of disused sealed sources. Assignments listed below: 1. Dismantling; 2. Packaging; 3. Return of disused sealed radioactive sources. The actions taken were carried out by the technical teams of the Bolivian Institute of Nuclear Science and Technology (IBTEN) and Los Alamos National Laboratory (LANS) which supports the program 'Global Threat Reduction Initiative's' (GTRI) in the implementation of 'Off -site Source Recovery Program' (OSRP). [es

  9. Disposition of excess weapons plutonium from dismantled weapons

    International Nuclear Information System (INIS)

    Jardine, L.J.

    1997-01-01

    With the end of the Cold War and the implementation of various nuclear arms reduction agreements, US and Russia have been actively dismantling tens of thousands of nuclear weapons. As a result,large quantities of fissile materials, including more than 100 (tonnes?) of weapons-grade Pu, have become excess to both countries' military needs. To meet nonproliferation goals and to ensure the irreversibility of nuclear arms reductions, this excess weapons Pu must be placed in secure storage and then, in timely manner, either used in nuclear reactors as fuel or discarded in geologic repositories as solid waste. This disposition in US and Russia must be accomplished in a safe, secure manner and as quickly as practical. Storage of this Pu is a prerequisite to any disposition process, but the length of storage time is unknown. Whether by use as fuel or discard as solid waste, disposition of that amount of Pu will require decades--and perhaps longer, if disposition operations encounter delays. Neither US nor Russia believes that long-term secure storage is a substitute for timely disposition of excess Pu, but long-term, safe, secure storage is a critical element of all excess Pu disposition activities

  10. Disposal of fissionable material from dismantled nuclear weapons

    International Nuclear Information System (INIS)

    Taylor, J.J.

    1991-01-01

    The reduction in tensions between the United States and the Soviet Union has improved the prospects for nuclear disarmament, making it more likely that significant numbers of nuclear warheads will be dismantled by the United States and USSR in the foreseeable future. Thus, the question becomes more urgent as to the disposition of the weapons materials, highly enriched uranium and plutonium. It is timely, therefore, to develop specific plans for such disposal. The overall process for disposal of weapons materials by the burnup option involves the following steps: (1) removing the weapons material from the warheads, (2) converting the material to a fuel form suitable for power reactors, (3) burning it up as a power reactor fuel, and (4) removing the spent fuel and placing it in a permanent repository. This paper examines these four steps with the purpose of answering the following questions. What facilities would be appropriate for the disposal process? Do they need to be dedicated facilities, or could industrial facilities be used? What is the present projection of the economics of the burnup process, both the capital investment and the operating costs? How does one assure that fissionable materials will not be diverted to military use during the disposal process? Is the spent fuel remaining from the burnup process proliferation resistant? Would the disposal of spent fuel add an additional burden to the spent fuel permanent repository? The suggested answers are those of the author and do not represent a position by the Electric Power Research Institute

  11. Rosie: A mobile worksystem for decontamination and dismantlement operations

    International Nuclear Information System (INIS)

    Thompson, B.R.; Conley, L.

    1996-01-01

    RedZone Robotics, Inc. and Carnegie Mellon University's Field Robotics Center have undertaken a contract to develop a next-generation worksystem for decommissioning and dismantlement tasks in Department of Energy (DOE) facilities. Currently, the authors are closing the second phase of this three phase effort and have completed the design and fabrication of the worksystem: Rosie. Rosie includes a locomotor, heavy manipulator, control center, and control system for robot operation. The locomotor is an omni-directional platform with tether management and hydraulic power capabilities. The heavy manipulator is a high-payload, long-reach system intended to deploy tools into the work area. The heavy manipulator is capable of deploying systems such as the Dual-Arm Work Module--a five degree-of-freedom platform supporting two highly dexterous manipulators--or a single manipulator for performing simpler, less dexterous tasks. Rosie is telerobotic to the point of having servo-controlled motions which can be operated and coordinated through the control center

  12. Gaukang and White Coup: Dismantling of Traditional Power

    Directory of Open Access Journals (Sweden)

    Nila Sastrawati

    2017-12-01

    Full Text Available This paper discusses the concept of power adhered to by the South Sulawesi community and explains the power struggle which had occurred both in the past and present. The South Sulawesi community’s conceptiontraditional power on power signifies a strong, transcendental relationship between themselves and supernatural powers, wherein all objects possessing certain peculiarities are inseparable from the stable and unchanging cosmic world. Thus, gaukang holds a significant position in the life of the South Sulawesi community, particularly pertaining to matters of power struggle. The waxing and waning of traditional power in South Sulawesi is determined by at least three factors: firstly, a change in power patterns with the emergence of new elites having a commoner background; secondly, incessant resistance to feudalistic rule; and lastly, the application of modern bureaucratic model. The general conclusion of this paper emphasizes the position of gaukang as a central point affecting the various power struggles that occurred throughout the history of the South Sulawesi community. The enactment of Regional Regulation (Perda No. 5 year 2016 on the Organization of Gowa Regency Local Cultural and Customary Institution provides a peek at how bureaucratic power had dismantled traditional power in Gowa Regency, which included, consequently, the transfer of authority over the royal heirlooms or gaukang of the Gowa Kingdom.

  13. Treatment of concrete bars from the dismantling of hot cells

    International Nuclear Information System (INIS)

    Graf, A.; Stutz, U.; Valencia, L.

    2002-01-01

    The Central Decontamination Operations Department (HDB) of the Karlsruhe Research Center operates facilities for the disposal of radioactive waste. In general, their objective is to decontaminate radioactive residues for unrestricted release in order to minimize the volume of waste products suitable for repository storage. In the case of about 120 concrete bars from the dismantling of hot cells, we reduce the volume of radioactive waste by sawing off the most contaminated parts of the bar. If there are no insertions such as cables or ventilation systems, the rest of the bar is sandblasted and its activity manually measured to ensure compliance with the release criteria. Otherwise, the bar is minced into small pieces by a power shovel. Afterwards, the rubble is filled into drums and its activity is measured by the clearance measurement facility. If the rubble and the sandblasted bars do not exceed the activity limit specified by the release criteria, the material is disposed of without further regulations for unrestricted use. Those parts of the bars which can not be released must be stored in special containers suitable for the KONRAD final disposal. Using this method, about 70 % of the total mass can be released. (author)

  14. Rosie: A mobile workstation for decontamination and dismantlement operations

    International Nuclear Information System (INIS)

    1994-01-01

    RedZone Robotics, Inc. and Carnegie Mellon University's Field Robotics Center have undertaken a contract to develop a next-generation worksystem for decommissioning and dismantlement tasks in Department of Energy (DOE) facilities. Currently, the authors are in the second phase of this three phase effort and are completing the design of the worksystem. Within this project RedZone is designing and fabricating a worksystem: Rosie. Rosie will include a locomotor, heavy manipulator, control center, and control system for robot operation. The locomotor is an omni-directional platform with tether management and hydraulic power capabilities. The heavy manipulator is a high-payload, long-reach system to deploy tools into the work area. The heavy manipulator will be capable of deploying systems such as the Dual-Arm Work Module--a five degree-of-freedom platform supporting two highly dexterous manipulators--or a single manipulator for performing simpler, less dexterous tasks. Rosie will be telerobotic to the point of having servo-controlled motions which can be operated and coordinated through the control center. This report describes the design of the systems. In phase three Rosie will be radiation-hardened and perform a demonstration in a contaminated facility

  15. Dismantling method for reactor pressure vessel and system therefor

    International Nuclear Information System (INIS)

    Hayashi, Makoto; Enomoto, Kunio; Kurosawa, Koichi; Saito, Hideyo.

    1994-01-01

    Upon dismantling of a reactor pressure vessel, a containment building made of concretes is disposed underground and a spent pressure vessel is contained therein, and incore structures are contained in the spent pressure vessel. Further, a plasma-welder and a pressing machine are disposed to a pool for provisionally placing reactor equipments in the reactor building for devoluming the incore structures by welding and compression. An overhead-running crane and rails therefor are disposed on the roof and the outer side of the reactor building for transporting the pressure vessel from the reactor building to the containment building. They may be contained in the containment building after incorporation of the incore structures into the pressure vessel at the outside of the reactor building. For the devoluming treatment, a combination of cutting, welding, pressing and the like are optically conducted. A nuclear power plant can be installed by using a newly manufactured nuclear reactor, with no requirement for a new site and it is unnecessary to provide a new radioactive waste containing facility. (N.H.)

  16. Management of wastes from dismantled nuclear power plants

    International Nuclear Information System (INIS)

    1979-01-01

    The problems associated with the management of radioactive wastes encountered in the dismantling of a 1200MWe PWR reactor are considered. It is possible to extend all the conclusions reached in these studies to BWR's or other reactors of the same type using light water as a coolant and moderator. The studies performed established the specific characteristics of these wastes: a gamma activity due essentially to 60 Co (after some fifty years this radioisotope will have decayed sufficiently to enable it to be stored without shielding); the presence of 63 Ni and 59 Ni (these long half-life beta emitting radioisotopes need to be stored over a long or even indefinite period of time); contaminated components (60% of the overall wastes), the reselling of these components involving costly decontamination processes. Extensive studies have been conducted on the management and handling of these wastes: packaging, transport, processing, storage and a great many techniques have been developed. However, further developments in concentration methods (fusion, crushing, cryogenics etc) and the selection of storage sites for this type of waste are necessary. Depending on the solutions chosen, the global cost of the wastes coming from a 1200 MW PWR reactor can vary between 10 and 20 million BFR

  17. TgICMAP1 is a novel microtubule binding protein in Toxoplasma gondii.

    Directory of Open Access Journals (Sweden)

    Aoife T Heaslip

    Full Text Available The microtubule cytoskeleton provides essential structural support for all eukaryotic cells and can be assembled into various higher order structures that perform drastically different functions. Understanding how microtubule-containing assemblies are built in a spatially and temporally controlled manner is therefore fundamental to understanding cell physiology. Toxoplasma gondii, a protozoan parasite, contains at least five distinct tubulin-containing structures, the spindle pole, centrioles, cortical microtubules, the conoid, and the intra-conoid microtubules. How these five structurally and functionally distinct sets of tubulin containing structures are constructed and maintained in the same cell is an intriguing problem. Previously, we performed a proteomic analysis of the T. gondii apical complex, a cytoskeletal complex located at the apical end of the parasite that is composed of the conoid, three ring-like structures, and the two short intra-conoid microtubules. Here we report the characterization of one of the proteins identified in that analysis, TgICMAP1. We show that TgICMAP1 is a novel microtubule binding protein that can directly bind to microtubules in vitro and stabilizes microtubules when ectopically expressed in mammalian cells. Interestingly, in T. gondii, TgICMAP1 preferentially binds to the intra-conoid microtubules, providing us the first molecular tool to investigate the intra-conoid microtubule assembly process during daughter construction.

  18. Stabilizing versus Destabilizing the Microtubules: A Double-Edge Sword for an Effective Cancer Treatment Option?

    Directory of Open Access Journals (Sweden)

    Daniele Fanale

    2015-01-01

    Full Text Available Microtubules are dynamic and structural cellular components involved in several cell functions, including cell shape, motility, and intracellular trafficking. In proliferating cells, they are essential components in the division process through the formation of the mitotic spindle. As a result of these functions, tubulin and microtubules are targets for anticancer agents. Microtubule-targeting agents can be divided into two groups: microtubule-stabilizing, and microtubule-destabilizing agents. The former bind to the tubulin polymer and stabilize microtubules, while the latter bind to the tubulin dimers and destabilize microtubules. Alteration of tubulin-microtubule equilibrium determines the disruption of the mitotic spindle, halting the cell cycle at the metaphase-anaphase transition and, eventually, resulting in cell death. Clinical application of earlier microtubule inhibitors, however, unfortunately showed several limits, such as neurological and bone marrow toxicity and the emergence of drug-resistant tumor cells. Here we review several natural and synthetic microtubule-targeting agents, which showed antitumor activity and increased efficacy in comparison to traditional drugs in various preclinical and clinical studies. Cryptophycins, combretastatins, ombrabulin, soblidotin, D-24851, epothilones and discodermolide were used in clinical trials. Some of them showed antiangiogenic and antivascular activity and others showed the ability to overcome multidrug resistance, supporting their possible use in chemotherapy.

  19. Decommissioning of nuclear facilities: COGEMA expertise devoted to UP1 reprocessing plant dismantling programme

    International Nuclear Information System (INIS)

    Gay, A.

    2001-01-01

    Over the last past decades, the French nuclear industry has acquired a great experience and know-how in the field of dismantling. Today this experience amounts to more than 200,000 hours. The fundamental aims within dismantling strategy are the same as for all nuclear facilities: minimising doses received by workers, minimising waste volume and adapting waste management to radioactivity levels, minimising costs. French experience is based on technologies which are currently used in nuclear maintenance facilities. Dismantling is a dynamic process especially in the field of decontamination (chemical and mechanical), cleaning, robotics and remote control operations. The strategy for the dismantling of former UP1 reprocessing plant is based on the feedback of experience gained through the dismantling of other facilities such as the AT1 workshop at La Hague. This workshop, a pilot plant for reprocessing of fast-breeder reactor fuels (Rapsodie and Phenix) has to be dismantled to IAEA level 3 (unrestricted site use), excluding civil works structures. Currently conducted by trained shifts, this dismantling project should end in 1999. The experience already acquired proves that chemical rinsings with the use of specific reagents is sufficient to decontaminate the hot cells and that the use of remote operations or robotics is not as important as previously envisaged. The UP1 reprocessing plant of Marcoule operated from 1958 to 1997. End of the operation was pronounced on the 31st of December 1997. 20,000 tons of spent fuels were reprocessed at UP1. The cleaning and dismantling operations at the Marcoule site depend upon the CEA, EDF and COGEMA. The Defence and Industry Ministries asked for a specific structure to be set up. An economic interest group called CODEM was created in May 1996. CODEM decides, finances and supervises dismantling operations, while respecting the constraints of nuclear safety, environmental protection and cost-effectiveness. The cleaning operations of

  20. Microtubule dynamics. II. Kinetics of self-assembly

    DEFF Research Database (Denmark)

    Flyvbjerg, H.; Jobs, E.

    1997-01-01

    Inverse scattering theory describes the conditions necessary and sufficient to determine an unknown potential from known scattering data. No similar theory exists for when and how one may deduce the kinetics of an unknown chemical reaction from quantitative information about its final state and i...... to analyze the self-assembly of microtubules from tubulin are general, and many other reactions and processes may be studied as inverse problems with these methods when enough experimental data are available....

  1. Vibrations of microtubules: Physics that has not met biology yet

    Czech Academy of Sciences Publication Activity Database

    Kučera, Ondřej; Havelka, Daniel; Cifra, Michal

    2017-01-01

    Roč. 72, 1 July (2017), s. 13-22 ISSN 0165-2125 R&D Projects: GA ČR(CZ) GA15-17102S Grant - others:AV ČR(CZ) SAV-15-22 Program:Bilaterální spolupráce Institutional support: RVO:67985882 Keywords : Models * Vibrations * Microtubules Subject RIV: BO - Biophysics OBOR OECD: Biophysics Impact factor: 1.575, year: 2016

  2. Dictyoceratidan poisons: Defined mark on microtubule-tubulin dynamics.

    Science.gov (United States)

    Gnanambal K, Mary Elizabeth; Lakshmipathy, Shailaja Vommi

    2016-03-01

    Tubulin/microtubule assembly and disassembly is characterized as one of the chief processes during cell growth and division. Hence drugs those perturb these process are considered to be effective in killing fast multiplying cancer cells. There is a collection of natural compounds which disturb microtubule/tubulin dis/assemblage and there have been a lot of efforts concerted in the marine realm too, to surveying such killer molecules. Close to half the natural compounds shooting out from marine invertebrates are generally with no traceable definite mechanisms of action though may be tough anti-cancerous hits at nanogram levels, hence fatefully those discoveries conclude therein without a capacity of translation from laboratory to pharmacy. Astoundingly at least 50% of natural compounds which have definite mechanisms of action causing disorders in tubulin/microtubule kinetics have an isolation history from sponges belonging to the Phylum: Porifera. Poriferans have always been a wonder worker to treat cancers with a choice of, yet precise targets on cancerous tissues. There is a specific order: Dictyoceratida within this Phylum which has contributed to yielding at least 50% of effective compounds possessing this unique mechanism of action mentioned above. However, not much notice is driven to Dictyoceratidans alongside the order: Demospongiae thus dictating the need to know its select microtubule/tubulin irritants since the unearthing of avarol in the year 1974 till date. Hence this review selectively pinpoints all the compounds, noteworthy derivatives and analogs stemming from order: Dictyoceratida focusing on the past, present and future. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Microscale force response and morphology of tunable co-polymerized cytoskeleton networks

    Science.gov (United States)

    Ricketts, Shea; Yadav, Vikrant; Ross, Jennifer L.; Robertson-Anderson, Rae M.

    The cytoskeleton is largely comprised of actin and microtubules that entangle and crosslink to form complex networks and structures, giving rise to nonlinear multifunctional mechanics in cells. The relative concentrations of semiflexible actin filaments and rigid microtubules tune cytoskeleton function, allowing cells to move and divide while maintaining rigidity and resilience. To elucidate this complex tunability, we create in vitro composites of co-polymerized actin and microtubules with actin:microtubule molar ratios of 0:1-1:0. We use optical tweezers and confocal microscopy to characterize the nonlinear microscale force response and morphology of the composites. We optically drag a microsphere 30 μm through varying actin-microtubule networks at 10 μm/s and 20 μm/s, and measure the force the networks exerts to resist the strain and the force relaxation following strain. We use dual-color confocal microscopy to image distinctly-labeled filaments in the networks, and characterize the integration of actin and microtubules, network connectivity, and filament rigidity. We find that increasing the fraction of microtubules in networks non-monotonically increases elasticity and stiffness, and hinders force relaxation by suppressing network mobility and fluctuations. NSF CAREER Award (DMR-1255446), Scialog Collaborative Innovation Award funded by Research Corporation for Scientific Advancement (Grant No. 24192).

  4. GIT1 enhances neurite outgrowth by stimulating microtubule assembly

    Directory of Open Access Journals (Sweden)

    Yi-sheng Li

    2016-01-01

    Full Text Available GIT1, a G-protein-coupled receptor kinase interacting protein, has been reported to be involved in neurite outgrowth. However, the neurobiological functions of the protein remain unclear. In this study, we found that GIT1 was highly expressed in the nervous system, and its expression was maintained throughout all stages of neuritogenesis in the brain. In primary cultured mouse hippocampal neurons from GIT1 knockout mice, there was a significant reduction in total neurite length per neuron, as well as in the average length of axon-like structures, which could not be prevented by nerve growth factor treatment. Overexpression of GIT1 significantly promoted axon growth and fully rescued the axon outgrowth defect in the primary hippocampal neuron cultures from GIT1 knockout mice. The GIT1 N terminal region, including the ADP ribosylation factor-GTPase activating protein domain, the ankyrin domains and the Spa2 homology domain, were sufficient to enhance axonal extension. Importantly, GIT1 bound to many tubulin proteins and microtubule-associated proteins, and it accelerated microtubule assembly in vitro. Collectively, our findings suggest that GIT1 promotes neurite outgrowth, at least partially by stimulating microtubule assembly. This study provides new insight into the cellular and molecular pathogenesis of GIT1-associated neurological diseases.

  5. Topical Session on the Decommissioning and Dismantling Safety Case

    International Nuclear Information System (INIS)

    2002-01-01

    Set up by the Radioactive Waste Management Committee (RWMC), the WPDD brings together senior representatives of national organisations who have a broad overview of Decommissioning and Dismantling (D and D) issues through their work as regulators, implementers, R and D experts or policy makers. These include representatives from regulatory authorities, industrial decommissioners from the NEA Cooperative Programme on Exchange of Scientific and Technical Information on Nuclear Installation Decommissioning Projects (CPD), and cross-representation from the NEA Committee on Nuclear Regulatory Activities, the Committee on Radiation Protection and Public Health, and the RWMC. The EC is a member of the WPDD and the IAEA also participates. This ensures co-ordination amongst activities in these international programmes. Participation from civil society organisations is considered on a case by case basis, and has already taken place through the active involvement of the Group of Municipalities with Nuclear Installations at the first meeting of the WPDD At its second meeting, in Paris, 5-7 December 2001, the WPDD held two topical sessions on the D and D Safety Case and on the Management of Materials from D and D, respectively. This report documents the topical session on the safety case. The topical session was meant to provide an exchange of information and experience on the following issues: What topics should be included in a safety case? Of what should it consist? Is there sufficient and complete guidance nationally and internationally? How do practices differ internationally? Main boundary condition to this session was that it would deal with plants where spent fuel has been removed. Also the topical sessions was kept at a level that makes the most of the varied constituency of the WPDD. Namely, interface issues are important, and issue-identification and discussion was the immediate goal. There was less interest in examining areas where variability amongst national

  6. Radiological survey techniques for decontamination and dismantlement applications

    International Nuclear Information System (INIS)

    Ruesink, G.P.; Stempfley, D.H.; Pettit, P.J.; Warner, R.D.

    1997-01-01

    The Department of Energy's Fernald Environmental Management Project (FEMP) is engaged in an aggressive Program to remove all above ground structures as part of the Fernald sites final remediation remedy. Through the complete removal of major facilities such as Plant 7, Plant 4, and Plant 1, the FEMP has developed radiological survey approaches that are effective for the different phases of the Decontamination and Dismantlement (D ampersand D) process. Some of the most pressing challenges facing the FEMP are implementing effective, low cost methods for the D ampersand D of former process buildings while minimizing environmental effects. One of the key components to ensure minimal impact on the environment is the collection of radiological contamination information during the D ampersand D process to facilitate the decision making process. Prior to the final demolition of any structure, radiological surveys of floors, walls, and ceilings must take place. These surveys must demonstrate that contamination levels am below 5000 dpm removable beta/gamma for non-porous surfaces and below 1000 dpm removable-beta/gamma for all porous surfaces. Technique which can perform these activities in a safe, effective, and cost efficient manner are greatly desired. The FEMP has investigated new approaches to address this need. These techniques include sampling approaches using standard baseline methodology as well as innovative approaches to accelerate final radiological clearance processes. To further improve upon this process, the FEMP has investigated several new technologies through the Fernald Plant 1 Large Scale Technology Demonstration Project. One of the most promising of these new technologies, Laser Induced Fluorescence, may significantly improve the radiological clearance survey process. This paper will present real world experiences in applying radiological control limits to D ampersand D projects as well as relate potential productivity and cost improvements with the

  7. Deterministic Assessment of Future Costs for Dismantling (FA)

    Energy Technology Data Exchange (ETDEWEB)

    Vasko, Marek [DECOM, Trnava (Slovakia)

    2012-11-01

    The main objective of the report is to provide an re-evaluation of cost calculations by OMEGA code for the Intermediate Storage for Spent Fuel in Studsvik (FA facility) using up-to-date Swedish labour cost unit factors and available up-to-date Swedish (or international) cost unit factors for consumables, materials and substances. Furthermore, evolution of other OMEGA database parameters concerning cost calculations e.g. manpower unit factors and workgroups parameters are taken into account. This report follows up former project which introduced tentative calculations of main decommissioning parameters such as costs, manpower and exposure of personnel for activities of older nuclear facility decommissioning in Sweden represented by FA Facility in Studsvik by means of calculation code OMEGA. The project demonstrated an implementation of advanced costing methodology based on PSL structure format to achieve transparent, traceable and comparable estimates even for older nuclear facilities like FA Facility in Studsvik. This former project used Slovak origin labour costs unit factors and other cost unit factors. After successful completion of this project, there was an intent of SSM to reevaluate calculations using an up-to-date Swedish labour cost data and also available Swedish consumables and materials cost data if available. Within this report re-calculations of main decommissioning parameters using available Swedish data are presented in structure according to Proposed Standardized List of Items for Costing Purposes. Calculations are made for decommissioning scenario with post-dismantling decontamination and steel radwaste melting technologies available at the site. All parameters are documented and summed up in both table and graphic forms in text and Annexes. Further, comparison of calculated results with previous calculations together with discussion is provided.

  8. Deterministic Assessment of Future Costs for Dismantling (FA)

    International Nuclear Information System (INIS)

    Vasko, Marek

    2012-03-01

    The main objective of the report is to provide an re-evaluation of cost calculations by OMEGA code for the Intermediate Storage for Spent Fuel in Studsvik (FA facility) using up-to-date Swedish labour cost unit factors and available up-to-date Swedish (or international) cost unit factors for consumables, materials and substances. Furthermore, evolution of other OMEGA database parameters concerning cost calculations e.g. manpower unit factors and workgroups parameters are taken into account. This report follows up former project which introduced tentative calculations of main decommissioning parameters such as costs, manpower and exposure of personnel for activities of older nuclear facility decommissioning in Sweden represented by FA Facility in Studsvik by means of calculation code OMEGA. The project demonstrated an implementation of advanced costing methodology based on PSL structure format to achieve transparent, traceable and comparable estimates even for older nuclear facilities like FA Facility in Studsvik. This former project used Slovak origin labour costs unit factors and other cost unit factors. After successful completion of this project, there was an intent of SSM to reevaluate calculations using an up-to-date Swedish labour cost data and also available Swedish consumables and materials cost data if available. Within this report re-calculations of main decommissioning parameters using available Swedish data are presented in structure according to Proposed Standardized List of Items for Costing Purposes. Calculations are made for decommissioning scenario with post-dismantling decontamination and steel radwaste melting technologies available at the site. All parameters are documented and summed up in both table and graphic forms in text and Annexes. Further, comparison of calculated results with previous calculations together with discussion is provided

  9. Recycling of concrete waste generated from nuclear power plant dismantling

    International Nuclear Information System (INIS)

    Ogawa, Hideo; Nagase, Takahiro; Tanaka, Hiroaki; Nawa, Toyoharu

    2012-01-01

    Non-radioactive concrete waste generated from dismantling of a standard large nuclear power plant is estimated to be about 500,000 tons in weight. Using such waste as recycled aggregate within the enclosure of the plant requires a new manufacturing technology that generates a minimal amount of by-product powder. Recycled aggregate has brittle parts with defects such as cracks, pores, and voids in residual paste from original concrete. This study presents a method of selectively removing the defective parts during manufacture to improve the quality of the recycled fine aggregate. With this selective removal method used, the amount of by-product powder can be reduced by half as compared to that by a conventional method. The influences of the characteristics of the recycled fine aggregate on the flowability and strength of the mortar using recycled fine aggregate were evaluated by multiple linear regression analysis. The results clearly showed that the flowability was primarily affected by the filling fraction of recycled fine aggregate, while the compressive strength of mortar was primarily affected by the fraction of defects in the aggregate. It was also found that grains produced by a granulator have more irregularities in the surfaces than those produced by a ball mill, providing an increased mortar strength. Using these findings from this study, efforts are also being made to develop a mechanical technology that enables simultaneous processing of decontamination and recycling. The granulator under consideration is capable of grinding the surfaces of irregularly shaped particles and may be used successfully, under optimal conditions, for the surface decontamination of concrete waste contaminated with radioactive materials. (author)

  10. The inherent advantages of delayed dismantling of decommissioning nuclear stations

    International Nuclear Information System (INIS)

    Liederman, J.M.; Saroudis, J.I.

    1985-01-01

    Recent studies in Canada pertaining to the decommissioning of the CANDU 600 MW(e) reactor have led to the development of the option of a ''static state'' condition. This alternative is based on judging risk and benefit to society considering the greatly reduced potential radiation exposure to personnel after 30 to 80 years have elapsed, following the final shutdown of the reactor. After approximately 80 to 120 years have elapsed, the decay in all systems and components (with the exception of the reactor assembly) would be such that radiation fields would be at background levels producing an environment that would be acceptable for Stage 3 decommissiong. This philosophy is based on the current engineering judgement that: - All systems, components, and structures which were associated with the nuclear processes and are radioactive, can be put into a static or storage state, and a containment function maintained at low cost for prolonged periods of between 80 to 120 years. - Between 80 to 120 years after shutdown, most of the radioactivity, except for some long lived radionuclides in the reactor vessel itself and its vault, will have naturally decayed to near releasable limits without any external intervention. - There is a lower overall risk to society in this approach, than dismantling and transporting radioactive materials prematurely. This philosophy is developed taking into consideration radiation protection, financial and risk assessment issues. The Canadian concept of dry storage of spent fuel is part of this philosophy and may be of interest to decommissioned nuclear plants of other types. 4 tables, 5 graphs

  11. Preliminary dismantling for the decommissioning of nuclear licensed facilities at the CEA Centre in Fontenay aux Roses

    International Nuclear Information System (INIS)

    Estivie, D.; Bohar, M.P.; Jeanjacques, M.; Binet, C.

    2008-01-01

    Under the perimeter modification programme for the Nuclear Licensed Facilities (NLFs) of the French Atomic Energy Commission centre at Fontenay aux Roses (CEN-FAR), preliminary dismantling work proved necessary to decommission the buildings outside the nuclear perimeter and create interim storage areas for waste packages. This summary describes the dismantling of Buildings 07, 53 and 91/54, which are the most representative of the preliminary dismantling work. (author)

  12. The Drosophila Microtubule-Associated Protein Mars Stabilizes Mitotic Spindles by Crosslinking Microtubules through Its N-Terminal Region

    Science.gov (United States)

    Zhang, Gang; Beati, Hamze; Nilsson, Jakob; Wodarz, Andreas

    2013-01-01

    Correct segregation of genetic material relies on proper assembly and maintenance of the mitotic spindle. How the highly dynamic microtubules (MTs) are maintained in stable mitotic spindles is a key question to be answered. Motor and non-motor microtubule associated proteins (MAPs) have been reported to stabilize the dynamic spindle through crosslinking adjacent MTs. Mars, a novel MAP, is essential for the early development of Drosophila embryos. Previous studies showed that Mars is required for maintaining an intact mitotic spindle but did not provide a molecular mechanism for this function. Here we show that Mars is able to stabilize the mitotic spindle in vivo. Both in vivo and in vitro data reveal that the N-terminal region of Mars functions in the stabilization of the mitotic spindle by crosslinking adjacent MTs. PMID:23593258

  13. The Drosophila microtubule-associated protein mars stabilizes mitotic spindles by crosslinking microtubules through its N-terminal region.

    Directory of Open Access Journals (Sweden)

    Gang Zhang

    Full Text Available Correct segregation of genetic material relies on proper assembly and maintenance of the mitotic spindle. How the highly dynamic microtubules (MTs are maintained in stable mitotic spindles is a key question to be answered. Motor and non-motor microtubule associated proteins (MAPs have been reported to stabilize the dynamic spindle through crosslinking adjacent MTs. Mars, a novel MAP, is essential for the early development of Drosophila embryos. Previous studies showed that Mars is required for maintaining an intact mitotic spindle but did not provide a molecular mechanism for this function. Here we show that Mars is able to stabilize the mitotic spindle in vivo. Both in vivo and in vitro data reveal that the N-terminal region of Mars functions in the stabilization of the mitotic spindle by crosslinking adjacent MTs.

  14. The Drosophila microtubule-associated protein mars stabilizes mitotic spindles by crosslinking microtubules through its N-terminal region.

    Science.gov (United States)

    Zhang, Gang; Beati, Hamze; Nilsson, Jakob; Wodarz, Andreas

    2013-01-01

    Correct segregation of genetic material relies on proper assembly and maintenance of the mitotic spindle. How the highly dynamic microtubules (MTs) are maintained in stable mitotic spindles is a key question to be answered. Motor and non-motor microtubule associated proteins (MAPs) have been reported to stabilize the dynamic spindle through crosslinking adjacent MTs. Mars, a novel MAP, is essential for the early development of Drosophila embryos. Previous studies showed that Mars is required for maintaining an intact mitotic spindle but did not provide a molecular mechanism for this function. Here we show that Mars is able to stabilize the mitotic spindle in vivo. Both in vivo and in vitro data reveal that the N-terminal region of Mars functions in the stabilization of the mitotic spindle by crosslinking adjacent MTs.

  15. Regulation of developmental and environmental signaling by interaction between microtubules and membranes in plant cells

    Directory of Open Access Journals (Sweden)

    Qun Zhang

    2015-12-01

    Full Text Available ABSTRACT Cell division and expansion require the ordered arrangement of microtubules, which are subject to spatial and temporal modifications by developmental and environmental factors. Understanding how signals translate to changes in cortical microtubule organization is of fundamental importance. A defining feature of the cortical microtubule array is its association with the plasma membrane; modules of the plasma membrane are thought to play important roles in the mediation of microtubule organization. In this review, we highlight advances in research on the regulation of cortical microtubule organization by membrane-associated and membrane-tethered proteins and lipids in response to phytohormones and stress. The transmembrane kinase receptor Rho-like guanosine triphosphatase, phospholipase D, phosphatidic acid, and phosphoinositides are discussed with a focus on their roles in microtubule organization.

  16. NAD+ and SIRT3 control microtubule dynamics and reduce susceptibility to antimicrotubule agents

    Science.gov (United States)

    Harkcom, William T.; Ghosh, Ananda K.; Sung, Matthew S.; Matov, Alexandre; Brown, Kevin D.; Giannakakou, Paraskevi; Jaffrey, Samie R.

    2014-01-01

    Nicotinamide adenine dinucleotide (NAD+) is an endogenous enzyme cofactor and cosubstrate that has effects on diverse cellular and physiologic processes, including reactive oxygen species generation, mitochondrial function, apoptosis, and axonal degeneration. A major goal is to identify the NAD+-regulated cellular pathways that may mediate these effects. Here we show that the dynamic assembly and disassembly of microtubules is markedly altered by NAD+. Furthermore, we show that the disassembly of microtubule polymers elicited by microtubule depolymerizing agents is blocked by increasing intracellular NAD+ levels. We find that these effects of NAD+ are mediated by the activation of the mitochondrial sirtuin sirtuin-3 (SIRT3). Overexpression of SIRT3 prevents microtubule disassembly and apoptosis elicited by antimicrotubule agents and knockdown of SIRT3 prevents the protective effects of NAD+ on microtubule polymers. Taken together, these data demonstrate that NAD+ and SIRT3 regulate microtubule polymerization and the efficacy of antimicrotubule agents. PMID:24889606

  17. Linking cortical microtubule attachment and exocytosis [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Ivar Noordstra

    2017-04-01

    Full Text Available Exocytosis is a fundamental cellular process whereby secreted molecules are packaged into vesicles that move along cytoskeletal filaments and fuse with the plasma membrane. To function optimally, cells are strongly dependent on precisely controlled delivery of exocytotic cargo. In mammalian cells, microtubules serve as major tracks for vesicle transport by motor proteins, and thus microtubule organization is important for targeted delivery of secretory carriers. Over the years, multiple microtubule-associated and cortical proteins have been discovered that facilitate the interaction between the microtubule plus ends and the cell cortex. In this review, we focus on mammalian protein complexes that have been shown to participate in both cortical microtubule capture and exocytosis, thereby regulating the spatial organization of secretion. These complexes include microtubule plus-end tracking proteins, scaffolding factors, actin-binding proteins, and components of vesicle docking machinery, which together allow efficient coordination of cargo transport and release.

  18. The dynamic interplay of plasma membrane domains and cortical microtubules in secondary cell wall patterning

    Directory of Open Access Journals (Sweden)

    Yoshihisa eOda

    2013-12-01

    Full Text Available Patterning of the cellulosic cell wall underlies the shape and function of plant cells. The cortical microtubule array plays a central role in the regulation of cell wall patterns. However, the regulatory mechanisms by which secondary cell wall patterns are established through cortical microtubules remain to be fully determined. Our recent study in xylem vessel cells revealed that a mutual inhibitory interaction between cortical microtubules and distinct plasma membrane domains leads to distinctive patterning in secondary cell walls. Our research revealed that the recycling of active and inactive ROP proteins by a specific GAP and GEF pair establishes distinct de novo plasma membrane domains. Active ROP recruits a plant-specific microtubule-associated protein, MIDD1, which mediates the mutual interaction between cortical microtubules and plasma membrane domains. In this mini review, we summarize recent research regarding secondary wall patterning, with a focus on the emerging interplay between plasma membrane domains and cortical microtubules through MIDD1 and ROP.

  19. Shutdown, dismantling and decommissioning of nuclear facilities in France - Guide no. 6 - Update of 30/08/2016

    International Nuclear Information System (INIS)

    2016-01-01

    After a recall of the regulatory context and references, this guide addresses the strategy for an immediate dismantling of an installation, the dismantling planning, the different phases of the end of life of nuclear base installations, the authorization of definitive stop and dismantling, the preliminary phase preparing the definitive stop (regulatory context, technical aspects), the dismantling phase (regulatory context, technical aspects for the concerned operations, the security functions, hardware important for security, taking ageing into account), and the final status of installations (downgrading, constraints)

  20. Expertise of the Oeko-Institute on the application to obtain permission to partially dismantle the Niederaichbach nuclear power plant

    International Nuclear Information System (INIS)

    1985-01-01

    This expertise gives an overview on the problems associated with the decommissioning and dismantling of the Niederaichbach nuclear power plant, considering technical and legal aspects. It wants to prove that the dismantling of this reactor cannot serve as evidence to prove the general feasibility of reactor dismantling. Much space is dedicated to the discussion about where the borderline should be drawn between radioactive and non-radioactive materials according to the ordinance on radiation protection. The reasons for rejecting the partial dismantling application are given. (DG) [de

  1. State of dismantling of reactor facilities (JPDR) in Tokai Research Establishment, Japan Atomic Energy Research Institute (fiscal year 1986)

    International Nuclear Information System (INIS)

    1987-01-01

    As to this dismantling work, the contents of the notice on the dismantling and the policy of administration offices to deal with it were reported to the Nuclear Safety Commission beforehand, and after the approval was obtained, it has been executed. Based on the talk of the chairman of Nuclear Safety Commission on January 6, 1983, the state of dismantling is reported. In fiscal year 1986, the second stage dismantling was begun in December, and it was confirmed that the works were carried out safety. In order to ensure the place required for dismantling and removing in-core structures and the pressure vessel, the pressure vessel upper cover and its heat insulator were removed from the third story of the containment vessel. A part of the facilities installed on the second and third stories of the containment vessel was also dismantled and removed. In order to utilize as the place for the temporary preservation and decontamination of dismantled things, a part of the facilities installed in the dump condenser building was dismantled and removed. The control building was reconstructed for smoothly carrying out the entrance control of workers. 36 spent fuel assemblies were carried away for reprocessing. The exposure dose of workers was below the detectable limit of film badges. The dismantled wastes were about 171 t of metals and 34 t of concrete. (Kako, I.)

  2. Measuring and modeling polymer concentration profiles near spindle boundaries argues that spindle microtubules regulate their own nucleation

    Science.gov (United States)

    Kaye, Bryan; Stiehl, Olivia; Foster, Peter J.; Shelley, Michael J.; Needleman, Daniel J.; Fürthauer, Sebastian

    2018-05-01

    Spindles are self-organized microtubule-based structures that segregate chromosomes during cell division. The mass of the spindle is controlled by the balance between microtubule turnover and nucleation. The mechanisms that control the spatial regulation of microtubule nucleation remain poorly understood. While previous work found that microtubule nucleators bind to pre-existing microtubules in the spindle, it is still unclear whether this binding regulates the activity of those nucleators. Here we use a combination of experiments and mathematical modeling to investigate this issue. We measured the concentration of microtubules and soluble tubulin in and around the spindle. We found a very sharp decay in the concentration of microtubules at the spindle interface. This is inconsistent with a model in which the activity of nucleators is independent of their association with microtubules but consistent with a model in which microtubule nucleators are only active when bound to pre-existing microtubules. This argues that the activity of microtubule nucleators is greatly enhanced when bound to pre-existing microtubules. Thus, microtubule nucleators are both localized and activated by the microtubules they generate.

  3. Ase1p Organizes Antiparallel Microtubule Arrays during Interphase and Mitosis in Fission YeastV⃞

    OpenAIRE

    Loïodice, Isabelle; Staub, Jayme; Setty, Thanuja Gangi; Nguyen, Nam-Phuong T.; Paoletti, Anne; Tran, P. T.

    2005-01-01

    Proper microtubule organization is essential for cellular processes such as organelle positioning during interphase and spindle formation during mitosis. The fission yeast Schizosaccharomyces pombe presents a good model for understanding microtubule organization. We identify fission yeast ase1p, a member of the conserved ASE1/PRC1/MAP65 family of microtubule bundling proteins, which functions in organizing the spindle midzone during mitosis. Using fluorescence live cell imaging, we show that ...

  4. A mutation of the fission yeast EB1 overcomes negative regulation by phosphorylation and stabilizes microtubules

    International Nuclear Information System (INIS)

    Iimori, Makoto; Ozaki, Kanako; Chikashige, Yuji; Habu, Toshiyuki; Hiraoka, Yasushi; Maki, Takahisa; Hayashi, Ikuko; Obuse, Chikashi; Matsumoto, Tomohiro

    2012-01-01

    Mal3 is a fission yeast homolog of EB1, a plus-end tracking protein (+ TIP). We have generated a mutation (89R) replacing glutamine with arginine in the calponin homology (CH) domain of Mal3. Analysis of the 89R mutant in vitro has revealed that the mutation confers a higher affinity to microtubules and enhances the intrinsic activity to promote the microtubule-assembly. The mutant Mal3 is no longer a + TIP, but binds strongly the microtubule lattice. Live cell imaging has revealed that while the wild type Mal3 proteins dissociate from the tip of the growing microtubules before the onset of shrinkage, the mutant Mal3 proteins persist on microtubules and reduces a rate of shrinkage after a longer pausing period. Consequently, the mutant Mal3 proteins cause abnormal elongation of microtubules composing the spindle and aster. Mal3 is phosphorylated at a cluster of serine/threonine residues in the linker connecting the CH and EB1-like C-terminal motif domains. The phosphorylation occurs in a microtubule-dependent manner and reduces the affinity of Mal3 to microtubules. We propose that because the 89R mutation is resistant to the effect of phosphorylation, it can associate persistently with microtubules and confers a stronger stability of microtubules likely by reinforcing the cylindrical structure. -- Highlights: ► We characterize a mutation (mal3-89R) in fission yeast homolog of EB1. ► The mutation enhances the activity to assemble microtubules. ► Mal3 is phosphorylated in a microtubule-dependent manner. ► The phosphorylation negatively regulates the Mal3 activity.

  5. A mutation of the fission yeast EB1 overcomes negative regulation by phosphorylation and stabilizes microtubules

    Energy Technology Data Exchange (ETDEWEB)

    Iimori, Makoto; Ozaki, Kanako [Graduate School of Biostudies, Kyoto University, Kitashirakawa-Oiwake cho, Sakyo ku, Kyoto, 606-8502 (Japan); Chikashige, Yuji [Kobe Advanced ICT Research Center, National Institute of Information and Communications Technology, Kobe, 651-2492 (Japan); Habu, Toshiyuki [Graduate School of Biostudies, Kyoto University, Kitashirakawa-Oiwake cho, Sakyo ku, Kyoto, 606-8502 (Japan); Radiation Biology Center, Kyoto University, Yoshida-Konoe cho, Sakyo ku, Kyoto, 606-8501 (Japan); Hiraoka, Yasushi [Kobe Advanced ICT Research Center, National Institute of Information and Communications Technology, Kobe, 651-2492 (Japan); Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, 565-0871 (Japan); Maki, Takahisa; Hayashi, Ikuko [Graduate School of Nanobioscience, Yokohama City University, Tsurumi, Yokohama, 230-0045 (Japan); Obuse, Chikashi [Graduate School of Life Science, Hokkaido University, Sapporo 001-0021 (Japan); Matsumoto, Tomohiro, E-mail: tmatsumo@house.rbc.kyoto-u.ac.jp [Graduate School of Biostudies, Kyoto University, Kitashirakawa-Oiwake cho, Sakyo ku, Kyoto, 606-8502 (Japan); Radiation Biology Center, Kyoto University, Yoshida-Konoe cho, Sakyo ku, Kyoto, 606-8501 (Japan)

    2012-02-01

    Mal3 is a fission yeast homolog of EB1, a plus-end tracking protein (+ TIP). We have generated a mutation (89R) replacing glutamine with arginine in the calponin homology (CH) domain of Mal3. Analysis of the 89R mutant in vitro has revealed that the mutation confers a higher affinity to microtubules and enhances the intrinsic activity to promote the microtubule-assembly. The mutant Mal3 is no longer a + TIP, but binds strongly the microtubule lattice. Live cell imaging has revealed that while the wild type Mal3 proteins dissociate from the tip of the growing microtubules before the onset of shrinkage, the mutant Mal3 proteins persist on microtubules and reduces a rate of shrinkage after a longer pausing period. Consequently, the mutant Mal3 proteins cause abnormal elongation of microtubules composing the spindle and aster. Mal3 is phosphorylated at a cluster of serine/threonine residues in the linker connecting the CH and EB1-like C-terminal motif domains. The phosphorylation occurs in a microtubule-dependent manner and reduces the affinity of Mal3 to microtubules. We propose that because the 89R mutation is resistant to the effect of phosphorylation, it can associate persistently with microtubules and confers a stronger stability of microtubules likely by reinforcing the cylindrical structure. -- Highlights: Black-Right-Pointing-Pointer We characterize a mutation (mal3-89R) in fission yeast homolog of EB1. Black-Right-Pointing-Pointer The mutation enhances the activity to assemble microtubules. Black-Right-Pointing-Pointer Mal3 is phosphorylated in a microtubule-dependent manner. Black-Right-Pointing-Pointer The phosphorylation negatively regulates the Mal3 activity.

  6. Experience in dismantling and packaging of pressure vessel and core internals

    International Nuclear Information System (INIS)

    Pillokat, Peter; Bruhn, Jan Hendrik

    2011-01-01

    Nuclear Company AREVA is proud to look back on versatile experience in successfully dismantling nuclear components. After performing several minor dismantling projects and studies for nuclear power plants, AREVA completed the order for dismantling of all remaining Reactor Pressure Vessel internals at German Boiling Water Reactor Wuergassen NPP in October '08. During the onsite activities about 121 tons of steel were successfully cut and packed under water into 200l- drums, as the dismantling was performed partly in situ and partly in an underwater working tank. AREVA deployed a variety of different cutting techniques such as band sawing, milling, nibbling, compass sawing and water jet cutting throughout this project. After successfully finishing this task, AREVA dismantled the cylindrical part of the Wuergassen Pressure Vessel. During this project approximately 320 tons of steel were cut and packaged for final disposal, as dismantling was mainly performed by on air use of water jet cutting with vacuum suction of abrasive and kerfs material. The main clue during this assignment was the logistic challenge to handle and convey cut pieces from the pressure vessel to the packing area. For this, an elevator was installed to transport cut segments into the turbine hall, where a special housing was built for final storage conditioning. At the beginning of 2007, another complex dismantling project of great importance was acquired by AREVA. The contract included dismantling and conditioning for final storage of the complete RPV Internals of the German Pressurized Water Reactor Stade NPP. Very similar cutting techniques turned out to be the proper policy to cope this task. On-site activities took place in up to 5 separate working areas including areas for post segmentation and packaging to perform optimized parallel activities. All together about 85 tons of Core Internals were successfully dismantled at Stade NPP until September '09. To accomplish the best possible on

  7. Evaluation formulas of manpower needs for dismantling of equipments in uranium refining and conversion plant

    International Nuclear Information System (INIS)

    Izumo, Sari; Usui, Hideo; Kubota, Shintaro; Tachibana, Mitsuo; Kawagoshi, Hiroshi; Tokuyasu, Takashi; Takahashi, Nobuo; Morimoto, Yasuyuki; Tanaka, Yoshio; Sugitsue, Noritake

    2014-07-01

    Japan Atomic Energy Agency has developed PROject management data evaluation code for DIsmantling Activities (PRODIA) to make an efficient decommissioning for nuclear facilities. PRODIA is a source code which provides estimated value such as manpower needs, costs, etc., for dismantling by evaluation formulas according to the type of nuclear facility. Evaluation formulas of manpower needs for dismantling of equipments about reprocessed uranium conversion in Uranium Refining and Conversion Plant (URCP) have been developed in this report. In the result, evaluation formulas of manpower needs for dismantling of equipment were derived based on the classifications of equipment's functions or work items. These evaluation formulas are widely applicable to the estimation of the manpower needs for dismantling the other nuclear facilities, in particular uranium handling facilities. It was confirmed that some of these evaluation formulas with the same applicable condition could be unified to some inclusive evaluation formulas. It turned out that all steel equipment contaminated by uranium could be evaluated by one evaluation formula. (author)

  8. DECISION ANALYSIS SCIENCE MODELING FOR APPLICATION AND FIELDING SELECTION APPLIED TO EQUIPMENT DISMANTLEMENT TECHNOLOGIES

    International Nuclear Information System (INIS)

    Ebadian, M.A.

    1999-01-01

    The dismantlement of radioactively contaminated process equipment is a major concern during the D and D process. There are an estimated 1,200 buildings in the DOE-EM complex that will require the dismantlement of equipment and various metal structures. As buildings undergo the D and D process, this metallic equipment contaminated with radionuclides such as uranium and plutonium must be size-reduced before final disposal. A single information source comparing dismantlement technologies in the areas of safety, cost, and performance is needed by DOE managers and is not currently available. The selection of the appropriate technologies to meet the dismantlement objectives for a given site is a difficult process in the absence of comprehensive and comparable data. Choosing the wrong technology could result in increased exposure of personnel to contaminants and an increase in D and D project costs. The purpose of this investigation was to evaluate commercially available and innovative technologies for equipment dismantlement and provide a comprehensive source of information to the D and D community in the areas of technology performance, cost, and health and safety

  9. Processing of LLW arising from dismantling activities in a reprocessing facility

    International Nuclear Information System (INIS)

    Geens, L.G.; Geens, L.P.; Vandeven, I.

    1990-01-01

    The Eurochemic reprocessing facility, at the Mol-Dessel site in Belgium was in active operation from July 1966 until January 1975. In total, about 210 Mg of various types of irradiated nuclear fuels were processed. After the shut-down the plant has been partially decontaminated in view of recommissioning. When the recommissioning option was abandoned, the decision was taken in 1986 to dismantle the plant. A 2 years study resulted in the start of a pilot project: the dismantling of two smaller buildings, previously used for storage of uranyl nitrate and used solvent. The minimization of radioactive waste generation was also one of the major goals of this project. The report deals with the different steps in the minimization of radioactive waste generation during the dismantling activities. First, an estimation of the amounts of radioactive waste, expected to be generated, was made. In a second step the actual waste production during dismantling operations was minimized and compared with the estimations. Finally, a large part of the primary radioactive dismantling waste has been completely decontaminated, resulting in much lower amounts of nuclear waste generated. 2 refs., 3 figs., 2 tabs

  10. Dismantling of alpha contaminated obsolete installations and glove boxes on the IRMM site in Geel (Belgium)

    International Nuclear Information System (INIS)

    Cretskens, Pieter; Lenie, Koen; Melis, Gustaaf

    2007-01-01

    At the Institute for Reference Materials and Measurements (European commission, Joint Research Centre, IRMM) a dismantling campaign of obsolete installations and glove boxes has been carried out in 2005. There were various reasons for their removal. Some large installations did not meet modern safety standards, other installations were worn out and expected to cause a radioactive contamination risk in the future. The main goal was to create as less waste as possible by extensive contamination checks and by decontamination if necessary. For the glove boxes, decontamination was not possible. A controlled area was set up around the installation to be dismantled in order to prevent spreading of contamination from dust and dirt. This was only possible for the 'minor' contaminated installations. The dismantling campaign of the glove boxes was carried out by using tents of two types depending the contamination inside the glove boxes. The most common glove boxes were dismantled in a tent constructed with hard surfaced polycarbonate plates (ventilated cell). For glove boxes with higher contamination, the same principle was used but with a second 'glove box tent' inside (ventilated glove tent). The purpose of this project was to learn from the experience of this campaign which gave the ability to make estimates of future radioactive waste or classic waste that could be expected from dismantled installations. (authors)

  11. Experience with Dismantling of the Analytic Cell in the JRTF Decommissioning Program

    International Nuclear Information System (INIS)

    Annoh, Akio; Nemoto, Koichi; Tajiri, Hideo; Saito, Keiichiro; Miyajima, Kazutoshi; Myodo, Masato

    2003-01-01

    The analytic cell was mainly used for process control analysis of the reprocessing process and for the measurement of fuel burn up ratio in JAERI's Reprocessing Test Facility (JRTF). The analytic cell was a heavy shielded one and equipped with a conveyor. The cell was alpha and beta(gamma)contaminated. For dismantling of analytic cells, it is very important to establish a method to remove the heavy shield safely and reduce the exposure. At first, a green house was set up to prevent the spread out of contamination, and next, the analytic cell was dismantled. Depending on the contamination condition, the workers wore protective suits such as air ventilated-suits for prevention of internal exposure and vinyl chloride aprons, lead aprons in order to reduce external exposure. From the work carried out, various data such as needed manpower for the activities, the collective dose of workers by external exposure, the amount of radioactive wastes and the relation between the weight of the shield and its dismantling efficiency were obtained and input for the database. The method of dismantling and the experience with the dismantling of the analytic cell in the JRTF, carried out during 2001 and 2002, are described in this paper

  12. Taking into account of dismantling constraints in the design of nuclear facilities

    International Nuclear Information System (INIS)

    Gouhier, E.; Moitrier, C.; Girones, P.; Pitrou, Y.; Poncet, P.; O'Sullivan, P.

    2014-01-01

    The taking into account of dismantling constraints in the design of nuclear facilities allows the reduction of the dosimetry during the dismantling operations, the reduction of the amount of wastes to manage and the saving of time and money by foreseeing an adequate and simple solution for each component. It is to notice that the strategy of life-extension strengthens that of dismantling because life-extension implies the possibility for any component of the reactor except the pressure vessel to be replaced. The feedback experience capitalized on various types of nuclear facilities have enabled IAEA and OECD to publish recommendations to facilitate dismantling. For instance, pipes and ventilation ducts must be designed to minimize the deposit of dust and residues, the natural porosity of concrete must be limited through the use of polishing products or a metal liner, the type and concentrations of impurities present in the structure materials must be controlled to limit radioactivation, the documentation describing the facility must be kept up to date, or the history of contamination events must be recorded all along the life of the facility. The integration of the dismantling constraints in the design stage is illustrated with 3 examples: the Georges Besse 2 enrichment fuel plant, new reactors (EPR, ASTRID and RJH), and ITER. (A.C.)

  13. Combing and self-assembly phenomena in dry films of Taxol-stabilized microtubules

    Directory of Open Access Journals (Sweden)

    Rose Franck

    2007-01-01

    Full Text Available AbstractMicrotubules are filamentous proteins that act as a substrate for the translocation of motor proteins. As such, they may be envisioned as a scaffold for the self-assembly of functional materials and devices. Physisorption, self-assembly and combing are here investigated as a potential prelude to microtubule-templated self-assembly. Dense films of self-assembled microtubules were successfully produced, as well as patterns of both dendritic and non-dendritic bundles of microtubules. They are presented in the present paper and the mechanism of their formation is discussed.

  14. Msd1/SSX2IP-dependent microtubule anchorage ensures spindle orientation and primary cilia formation

    OpenAIRE

    Hori, Akiko; Ikebe, Chiho; Tada, Masazumi; Toda, Takashi

    2014-01-01

    Anchoring microtubules to the centrosome is critical for cell geometry and polarity, yet the molecular mechanism remains unknown. Here we show that the conserved human Msd1/SSX2IP is required for microtubule anchoring. hMsd1/SSX2IP is delivered to the centrosome in a centriolar satellite-dependent manner and binds the microtubule-nucleator ?-tubulin complex. hMsd1/SSX2IP depletion leads to disorganised interphase microtubules and misoriented mitotic spindles with reduced length and intensity....

  15. Cep169, a Novel Microtubule Plus-End-Tracking Centrosomal Protein, Binds to CDK5RAP2 and Regulates Microtubule Stability.

    Directory of Open Access Journals (Sweden)

    Yusuke Mori

    Full Text Available The centrosomal protein, CDK5RAP2, is a microcephaly protein that regulates centrosomal maturation by recruitment of a γ-tubulin ring complex (γ-TuRC onto centrosomes. In this report, we identified a novel human centrosomal protein, Cep169, as a binding partner of CDK5RAP2, a member of microtubule plus-end-tracking proteins (+TIPs. Cep169 interacts directly with CDK5RAP2 through CM1, an evolutionarily conserved domain, and colocalizes at the pericentriolar matrix (PCM around centrioles with CDK5RAP2. In addition, Cep169 interacts with EB1 through SxIP-motif responsible for EB1 binding, and colocalizes with CDK5RAP2 at the microtubule plus-end. EB1-binding-deficient Cep169 abolishes EB1 interaction and microtubule plus-end attachment, indicating Cep169 as a novel member of +TIPs. We further show that ectopic expression of either Cep169 or CDK5RAP2 induces microtubule bundling and acetylation in U2OS cells, and depletion of Cep169 induces microtubule depolymerization in HeLa cells, although Cep169 is not required for assembly of γ-tubulin onto centrosome by CDK5RAP2. These results show that Cep169 targets microtubule tips and regulates stability of microtubules with CDK5RAP2.

  16. Outsourcing and "dismantling" of steady jobs at hospitals.

    Science.gov (United States)

    Souza, Helton Saragor de; Mendes, Áquilas Nogueira

    2016-04-01

    To relate hospitals' organizational structure as the core of a web of outsourced services and flexible employment bonds among healthcare professionals in the context of finance capitalism, analyzing work arrangements based mainly on the type of employment bond. Qualitative research through ethnography, interviews, data analysis, and case studies. The case studies were concentrated in 3 hospitals located in the São Paulo metropolitan region under different management types: public administration; outsourced administration via a healthcare social organization (HSO); and private administration. This study highlights a trend in outsourcing, dismantling of steady jobs, and shaping working relations asymmetrically in terms of healthcare professions. These aspects are characteristic of contemporary capitalism and post-Fordist work organization. In this context, the state under sponsorship cripples the very existence of an effective human resources policy, creating a favorable environment for outsourcing and flexibility of employment bonds among healthcare workers. Relacionar a estrutura organizativa dos hospitais como núcleo de uma rede de serviços subcontratados e a flexibilização dos vínculos contratuais dos profissionais de saúde no contexto de capitalismo financeirizado, analisando os regimes de trabalho condicionados centralmente pelo vínculo empregatício. Pesquisa qualitativa através de etnografia, realização de entrevistas, análise de dados e utilização de estudo de caso. Os estudos de caso concentram-se em três hospitais localizados Região Metropolitana de São Paulo com gestões distintas: administração pública; administração terceirizada para Organização Social de Saúde (OSS); e administração privada. Destacamos a tendência da terceirização, do desmonte do emprego estável e a conformação de relações trabalhistas assimétricas para as profissões em saúde. Esses aspectos são característicos do período do capitalismo

  17. Vandellos 1 NPP. Dismantling at the level 1

    International Nuclear Information System (INIS)

    Pla, E.; Perez Pallares, J.

    1998-01-01

    . The radiological protection during dismantling activities took care of α contamination. The plant safety is always surveyed by the Regulatory Authority (CSN) which required to revise the Technical Specifications several times, according to the nuclear evolution of the site. (author)

  18. Drafting of the dismantling operations of the MAR 200 workshop with the help of virtual reality

    International Nuclear Information System (INIS)

    Chabal, C.; Soulabaille, Y.; Garnier, T.; Callixte, O.

    2014-01-01

    In order to optimize future dismantling operations of nuclear installations virtual reality allows the validation of predefined scenarios and their adequacy with the environment. CEA uses an immersion and interactive room to validate maintenance and dismantling operations. The equipment of this room is composed of a video wall that gives a 3-dimensional view of the virtual environment, and of a system for motion capture. For the simulation of handling operations a haptic interface has been designed, it allows the user to receive a tactic and effort-feeling feed back. The immersion is completed by a phonic ambience that creates sounds for virtual operations. The use of the immersion room for optimizing the dismantling of a spent fuel dissolver (MAR 200) used in hot cell is presented. (A.C.)

  19. Present status of refining and conversion facility dismantling. Progress in first half of 2010FY

    International Nuclear Information System (INIS)

    Kado, Kazumi; Sugitsue, Noritake; Morimoto, Yasuyuki; Ikegami, Sohei; Tanaka, Yoshio; Takahashi, Nobuo; Tokuyasu, Takashi

    2011-06-01

    The Refining and Conversion Facility located in the Ningyo-toge Environmental Engineering Center had the natural uranium conversion process and reprocessed uranium conversion process. The construction of this facility was started in 1979 and completed in October 1981. Dismantling of equipments in radiation controlled area of this facility was started from 2008, and all equipments in radiation controlled area will be dismantled by the 2011 fiscal year. This report describes the master plan of this decommissioning and shows as the progress in first half year of 2010FY, the actual time schedule, the method of decommissioning, the decommissioning progress appearance with photographs, work rates of each room / each worker class, and the quantity of dismantled materials and secondary wastes. (author)

  20. Present status of refining and conversion facility dismantling. Progress in first half of 2009FY

    International Nuclear Information System (INIS)

    Kado, Kazumi; Sugitsue, Noritake; Morimoto, Yasuyuki; Ikegami, Sohei; Tanaka, Yoshio; Takahashi, Nobuo; Tokuyasu, Takashi

    2010-03-01

    The Refining and Conversion Facility located in the Ningyo-toge Environmental Engineering Center had the natural uranium conversion process and reprocessed uranium conversion process. The construction of this facility was started in 1979 and completed in October 1981. Dismantling of equipments in radiation controlled area of this facility was started from 2008, and all equipments in radiation controlled area will be dismantled by the 2011 fiscal year. This report describes the master plan of this decommissioning and shows as the progress in first half year of 2009FY, the actual time schedule, the method of decommissioning, the decommissioning progress appearance with photographs, work rates of each room / each worker class, and the quantity of dismantled materials and secondary wastes. (author)

  1. Present status of refining and conversion facility dismantling. Progress in latter half of 2008FY

    International Nuclear Information System (INIS)

    Kado, Kazumi; Sugitsue, Noritake; Morimoto, Yasuyuki; Ikegami, Sohei; Takahashi, Nobuo; Tokuyasu, Takashi

    2010-01-01

    The Refining and Conversion Facility located in the Ningyo-toge Environmental Engineering Center had the natural uranium conversion process and reprocessed uranium conversion process. The construction of this facility was started in 1979 and completed in October 1981. Dismantling of equipments in radiation controlled area of this facility was started from 2008, and all equipments in radiation controlled area will be dismantled by the 2011 fiscal year. This report describes the master plan of this decommissioning and shows as the progress in latter half year of 2008FY, the actual time schedule, the method of decommissioning, the decommissioning progress appearance with photographs, work rates of each room/each worker class, and the quantity of dismantled materials and secondary wastes. (author)

  2. Manually-Operated Crate Dismantlement System for Los Alamos National Laboratory

    International Nuclear Information System (INIS)

    Laffitte, John; Lagos, Leo; Morales, Miguel

    2002-01-01

    Los Alamos National Laboratory currently possesses between 500 and 800 fiberglass-reinforced plywood crates that contain hazardous materials that need to be decontaminated. To access the hazardous material, a system is needed to dismantle the crate. Currently, crates are dismantled by workers using hand-held tools. This technique has numerous disadvantages. One disadvantage is that it is difficult for a worker to hold the tool for an extended period of time in the awkward angles and positions necessary to fully size-reduce the crate. Other disadvantages of using hand tools include managing power cords and vacuum hoses, which become entangled or can act as tripping hazards. In order to improve the crate opening and size-reduction task, Florida International University's Hemispheric Center for Environmental Technology (HCET) is developing a manually operated crate dismantlement system. This versatile system is expected to greatly increase worker efficiency while decreasing fatigue and the possibility of accidents. (authors)

  3. Deregulation in the field of decommissioning and dismantling of nuclear facilities

    International Nuclear Information System (INIS)

    Kurz, A.

    1994-05-01

    The report comprises two articles covering current topics of the decommissioning and dismantling of nuclear facilities. In the first article written by Kurz, the legal standards are listed together with conclusions and proposals regarding their implementation for the further development of this field of law. The article by Baumgaertel is aimed at evaluating the regulations governing nuclear technology as regards their applicability to the decommissioning and dismantling of nuclear facilities. These articles shall contribute to the discussions taking place in this field at the moment. As a result, an appropriate and project-specific application of the legal provisions and not legally binding (technical) regulations in the field of nuclear technology (deregulation) in the licensing procedures required for the decommissioning and dismantling of nuclear facilities is requested by the authors. (orig.) [de

  4. Reactor vessel dismantling at the high flux materials testing reactor Petten

    International Nuclear Information System (INIS)

    Tas, A.; Teunissen, G.

    1986-01-01

    The project of replacing the reactor vessel of the high flux materials testing reactor (HFR) originated in 1974 when results of several research programs confirmed severe neutron embrittlement of aluminium alloys suggesting a limited life of the existing facility. This report describes the dismantling philosophy and organisation, the design of special underwater equipment, the dismantling of the reactor vessel and thermal column, and the conditioning and shielding activities resulting in a working area for the installation of the new vessel with no access limitations due to radiation. Finally an overview of the segmentation, waste disposal and radiation exposure is given. The total dismantling, segmentation and conditioning activities resulted in a total collective radiation dose of 300 mSv. (orig.) [de

  5. Rockwell International Hot Laboratory decontamination and dismantlement interim progress report 1987-1996

    International Nuclear Information System (INIS)

    None

    1997-01-01

    OAK A271 Rockwell International Hot Laboratory decontamination and dismantlement interim progress report 1987-1996. The Rockwell International Hot Laboratory (RIHL) is one of a number of former nuclear facilities undergoing decontamination and decommissioning (D and D) at the Santa Susana Field Laboratory (SSFL). The RIHL facility is in the later stages of dismantlement, with the final objective of returning the site location to its original natural state. This report documents the decontamination and dismantlement activities performed at the facility over the time period 1988 through 1996. At this time, the support buildings, all equipment associated with the facility, and the entire above-ground structure of the primary facility building (Building 020) have been removed. The basement portion of this building and the outside yard areas (primarily asphalt and soil) are scheduled for D and D activities beginning in 1997

  6. International Cooperation for the Dismantling of Chooz A Reactor Pressure Vessel

    International Nuclear Information System (INIS)

    Grenouillet, J.J.; Posivak, E.

    2009-01-01

    Chooz A is the first PWR that is being decommissioned in France. The main issue that is conditioning the success of the project is the Reactor Pressure Vessel (RPV) and Reactor Vessel Internals (RVI) segmentation. Whereas Chooz A is the first and unique RPV and RVI being dismantled in France, there are many similar experiences available in the world. Thus the project team was eager to cooperate with other teams facing or being faced with the same issue. A cooperation programme was established in two separate ways: - Benefiting from experience feedback from completed RPV and RVI dismantling projects, - Looking for synergy with future RPV dismantling projects for activities such as segmentation tools design, qualification and manufacturing for example. This paper describes the implementation of this programme and how the outcome of the cooperation was used for the implementation of Chooz-A RPV and RVI segmentation project. It shows also the limits of such a cooperation. (authors)

  7. Radioactivity, radiation protection and monitoring during dismantling of light-water reactors

    International Nuclear Information System (INIS)

    Hummel, L.; Zech, J.B.

    2005-01-01

    Based on the radioactivity inventory in the systems and components of light-water reactors observed during operation, the impact of actions during plant emptying after the conclusion of power operation and possible subsequent long-term safe enclosure concerning the composition of the nuclide inventory of the plant to be dismantled will be described. Derived from this will be the effects on radioactivity monitoring in the plant, physical radiation protection monitoring, and the measured characterization of the residual materials resulting from the dismantling. The impact of long-term interim storage will also be addressed in the discussion. The talk should provide an overview of the interrelationships between source terms, decay times and the radioactivity monitoring requirements of the various dismantling concepts for commercial light-water reactors. (orig.)

  8. Stage 2: dismantling of reactor case of the experimental F.B.R. Rapsodie

    International Nuclear Information System (INIS)

    Roger, J.

    1994-01-01

    This document defines the main objectives of stage 2 dismantling of the Rapsodie experimental fast neutron reactor and specifies its time schedule. The work already in progress consists in containing the reactor vessel and its internal equipment, as well as the neutron protection concrete, inside the two leak-tight barriers, and in dismantling all the systems and equipment systems contaminated by sodium. This work, which includes the destruction of 37 metric tons of contaminated sodium from the primary system, was begun in 1987 and will be completed in 1994. The duration of the waiting period for complete dismantling (stage 3) has not been defined. However, the containment and monitoring means implemented should allow a safe waiting period of several decades. (author). 4 figs

  9. Remote dismantlement tasks for the CP5 reactor: Implementation, operations, and lessons learned

    International Nuclear Information System (INIS)

    Noakes, M.W.

    1998-01-01

    This paper presents a developer's perspective on lessons learned from one example of the integration of new prototype technology into a traditional operations environment. The dual arm work module was developed by the Robotics Technology Development Program as a research and development activity to examine manipulator controller modes and deployment options. It was later reconfigured for the dismantlement of the Argonne National Laboratory Chicago Pile number-sign 5 reactor vessel as the crane-deployed dual arm work platform. Development staff worked along side operations staff during a significant part of the deployment to provide training, maintenance, and tooling support. Operations staff completed all actual remote dismantlement tasks. At the end of available development support funding, the Dual Arm Work Platform was turned over to the operations staff, who is still using it to complete their dismantlement tasks

  10. Failure prevention with stress measurement for dismantling of nuclear facilities. Final report

    International Nuclear Information System (INIS)

    Komber, T.; Reimche, W.; Bach, F.W.

    2003-07-01

    The dismantling of nuclear facilities is in progress since 20 years in Germany. Practical experiences in decommissioning have shown, that problem can occur during dismantling operations caused by release of residual stresses. In this case cutting parts or cutting tools get jammed if mechanical cutting techniques are used. The aim of this research work was to develop measuring techniques for the determination of the stress state in RPV, to predict the deformation during dismantling operations. This can serve as additional base for improved decommissioning planning and for time optimised dismantling. For determination of the stress state in components two small and inexpensive measuring techniques were new designed, for remote-controlled on-site use in atmosphere and under water. For the nondestructive determination of the directional stress state, based on the magnetostriction and the Harmonic-Analysis of alternating magnetic fields, a new developed rotating sensor is in use with a principal magnetisation direction. Because of the mainly isotropic material properties and the directional stresses, measured Harmonic values are influenced mainly by the stress state in the surface areas. In this way it is possible to determine the stress state qualitatively and the direction of principal stresses in the surface areas of the component. As an alternative to the established wire strain gauge, which remote-controlled application is still not possible under water, a new slot jet cutting strain control technique was designed. This technique detects the deformation in the surface after stresses are cut free by a water jet. So the stress state could be determined quantitatively in the surface and assessed in the depth. With the help of these two measuring techniques it is possible to characterize the stress state along a planned cutting line. The use of an adapted FEM simulation enables to calculate and determine the deformation of the cutting gap beforehand. These information

  11. Development of equipments for remote dismantling of joule heated ceramic melter

    International Nuclear Information System (INIS)

    Badgujar, Kiran T.; Usarkar, Sachin G.; Kumar, Binu; Nair, K.N.S.

    2011-01-01

    Joule Heated Ceramic Melter (JHCM) technology has been adopted for industrial scale vitrification of high level liquid waste (HLLW) at Tarapur and Kalpakkam. The melter installed at Advanced Vitrification System (AVS), Tarapur has immobilized 175 m 3 of HLLW in 113 canisters containing 11533Kg of Vitrified Waste Product (VWP). The melter has been in operation for 3 years before shutdown. It is intended to demonstrate the complete procedure of dismantling of Joule Melter in 1:1 scale prior to going in for actual dismantling in the hot cell. The Melter consists of an assembly of Inconel/SS pipes and plates, fuse cast refractories, thermal insulations of various types inside a SS casing and possibly some glass which is left over in the melter. Dismantling of melter involves remote cutting of the outer casing, pipe connections, electrical connections and removal, sizing and packing of internals in a sequential manner to minimise generation of secondary waste. The challenge involves development of remotely operated multi-degrees of freedom fixtures, modification and performance testing of standard industrial cutting and breaking tools and adapting them for remote operations. The work also involves development of equipments for collection of waste generated during the dismantling operation and packaging thus in special packages. Remotely actuated fixtures have been developed for remote top plate and side electrodes cutting. Remotely operated grab has been developed for handling of loose material and grippers have been developed for handling of refractory blocks. Industrial vacuum suction device has been modified into split units to enable for reducing the spread of powder material, while dismantling in progress. The performance test of developed fixtures, equipments, cutting and breaking tools have been carried on 1:1 scale melter model. Various parameters like cutting speed, cutting tool performance, generation of waste volume has been measured and analysed for

  12. On the nature and shape of tubulin trails: implications on microtubule self-organization.

    Science.gov (United States)

    Glade, Nicolas

    2012-06-01

    Microtubules, major elements of the cell skeleton are, most of the time, well organized in vivo, but they can also show self-organizing behaviors in time and/or space in purified solutions in vitro. Theoretical studies and models based on the concepts of collective dynamics in complex systems, reaction-diffusion processes and emergent phenomena were proposed to explain some of these behaviors. In the particular case of microtubule spatial self-organization, it has been advanced that microtubules could behave like ants, self-organizing by 'talking to each other' by way of hypothetic (because never observed) concentrated chemical trails of tubulin that are expected to be released by their disassembling ends. Deterministic models based on this idea yielded indeed like-looking spatio-temporal self-organizing behaviors. Nevertheless the question remains of whether microscopic tubulin trails produced by individual or bundles of several microtubules are intense enough to allow microtubule self-organization at a macroscopic level. In the present work, by simulating the diffusion of tubulin in microtubule solutions at the microscopic scale, we measure the shape and intensity of tubulin trails and discuss about the assumption of microtubule self-organization due to the production of chemical trails by disassembling microtubules. We show that the tubulin trails produced by individual microtubules or small microtubule arrays are very weak and not elongated even at very high reactive rates. Although the variations of concentration due to such trails are not significant compared to natural fluctuations of the concentration of tubuline in the chemical environment, the study shows that heterogeneities of biochemical composition can form due to microtubule disassembly. They could become significant when produced by numerous microtubule ends located in the same place. Their possible formation could play a role in certain conditions of reaction. In particular, it gives a mesoscopic

  13. GIT1/βPIX signaling proteins and PAK1 kinase regulate microtubule nucleation.

    Science.gov (United States)

    Černohorská, Markéta; Sulimenko, Vadym; Hájková, Zuzana; Sulimenko, Tetyana; Sládková, Vladimíra; Vinopal, Stanislav; Dráberová, Eduarda; Dráber, Pavel

    2016-06-01

    Microtubule nucleation from γ-tubulin complexes, located at the centrosome, is an essential step in the formation of the microtubule cytoskeleton. However, the signaling mechanisms that regulate microtubule nucleation in interphase cells are largely unknown. In this study, we report that γ-tubulin is in complexes containing G protein-coupled receptor kinase-interacting protein 1 (GIT1), p21-activated kinase interacting exchange factor (βPIX), and p21 protein (Cdc42/Rac)-activated kinase 1 (PAK1) in various cell lines. Immunofluorescence microscopy revealed association of GIT1, βPIX and activated PAK1 with centrosomes. Microtubule regrowth experiments showed that depletion of βPIX stimulated microtubule nucleation, while depletion of GIT1 or PAK1 resulted in decreased nucleation in the interphase cells. These data were confirmed for GIT1 and βPIX by phenotypic rescue experiments, and counting of new microtubules emanating from centrosomes during the microtubule regrowth. The importance of PAK1 for microtubule nucleation was corroborated by the inhibition of its kinase activity with IPA-3 inhibitor. GIT1 with PAK1 thus represent positive regulators, and βPIX is a negative regulator of microtubule nucleation from the interphase centrosomes. The regulatory roles of GIT1, βPIX and PAK1 in microtubule nucleation correlated with recruitment of γ-tubulin to the centrosome. Furthermore, in vitro kinase assays showed that GIT1 and βPIX, but not γ-tubulin, serve as substrates for PAK1. Finally, direct interaction of γ-tubulin with the C-terminal domain of βPIX and the N-terminal domain of GIT1, which targets this protein to the centrosome, was determined by pull-down experiments. We propose that GIT1/βPIX signaling proteins with PAK1 kinase represent a novel regulatory mechanism of microtubule nucleation in interphase cells. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Katanin localization requires triplet microtubules in Chlamydomonas reinhardtii.

    Directory of Open Access Journals (Sweden)

    Jessica M Esparza

    Full Text Available Centrioles and basal bodies are essential for a variety of cellular processes that include the recruitment of proteins to these structures for both centrosomal and ciliary function. This recruitment is compromised when centriole/basal body assembly is defective. Mutations that cause basal body assembly defects confer supersensitivity to Taxol. These include bld2, bld10, bld12, uni3, vfl1, vfl2, and vfl3. Flagellar motility mutants do not confer sensitivity with the exception of mutations in the p60 (pf19 and p80 (pf15 subunits of the microtubule severing protein katanin. We have identified additional pf15 and bld2 (ε-tubulin alleles in screens for Taxol sensitivity. Null pf15 and bld2 alleles are viable and are not essential genes in Chlamydomonas. Analysis of double mutant strains with the pf15-3 and bld2-6 null alleles suggests that basal bodies in Chlamydomonas may recruit additional proteins beyond katanin that affect spindle microtubule stability. The bld2-5 allele is a hypomorphic allele and its phenotype is modulated by nutritional cues. Basal bodies in bld2-5 cells are missing proximal ends. The basal body mutants show aberrant localization of an epitope-tagged p80 subunit of katanin. Unlike IFT proteins, katanin p80 does not localize to the transition fibers of the basal bodies based on an analysis of the uni1 mutant as well as the lack of colocalization of katanin p80 with IFT74. We suggest that the triplet microtubules are likely to play a key role in katanin p80 recruitment to the basal body of Chlamydomonas rather than the transition fibers that are needed for IFT localization.

  15. Dismantling id the reactor pressure vessel insulation and dissecting of the MZFR reactor pressure vessel

    International Nuclear Information System (INIS)

    Loeb, Andreas; Stanke, Dieter; Thoma, Markus; Eisenmann, Beata; Prechtl, Erwin; Dehnke, Burckhard

    2008-01-01

    The MZFR reactor was decommissioned in 1984. The authors describe the dismantling of the reactor pressure vessel insulation that consists of asbestos containing mineral fiber wool. The appropriate remote handling and cutting tools had to be adapted with respect to the restrained space in the containment. The dismantling of the reactor pressure vessel has been completed, the dissected parts have been packaged into 200 containers for the final repository Konrad. During the total project time no reportable events and no damage to persons occurred.

  16. Days of dismantling activities of installations and rehabilitation of contaminated sites in France

    International Nuclear Information System (INIS)

    2008-01-01

    The objective of these days, organized by the section environment of the French society of radiation protection, is to present a panorama of the activities of nuclear installations dismantling and contaminated sites rehabilitation in France, by leaning in the same time on practical cases and by stating the French rule and the national and international recommendations on the subject. These days have also for object to approach the stakes associated with the sectors of waste management and the materials generated by these activities and in a more general way, the stakes to come for the different actors of the dismantling and the rehabilitation. (N.C.)

  17. General plan for the partial dismantling of the IRT-Sofia research reactor

    Directory of Open Access Journals (Sweden)

    Apostolov Tihomir G.

    2006-01-01

    Full Text Available After the decision of the Bulgarian Government to reconstruct it, the strategy concerning the IRT-Sofia Research Reactor is to partially dismantle the old systems and equipment. The removal of the reactor core and replacement of old equipment will not pose any significant problems. For a more efficient use of existing resources, there is a need for an engineering project which has been already prepared under the title "General Plan for the Partial Dismantling of Equipment at the IRT-Sofia as a Part of the Reconstruction into a Low Power RR".

  18. Study on safety evaluation for unrestricted recycling criteria of radioactive waste from dismantling operation

    International Nuclear Information System (INIS)

    Yoshimori, Michiro; Ohkoshi, Minoru; Abe, Masayoshi

    1995-01-01

    The study on safety evaluation was done, under contracting with the Science and Technology Agency, for recycling scrap metal arising from dismantling of reactor facilities. An object of this study is to contribute to the examination of establishing criteria and safety regulation for unrestricted recycling steel scrap. To define amount of market flow of iron material in Japan and the amount of radioactive waste generated from dismantling of reactor facilities, investigation had been carried out. On basis of these investigation results and data in several literature, individual doses to workers and to the members of the public have been calculated as well as collective doses. (author)

  19. Dismantling of Irradiation Facility Selfshielded of Investigation Model MPX- γ-25M

    International Nuclear Information System (INIS)

    Soguero, D.; Rapado, M.; Prieto, E.; Desdin, L.; Guerra, M.; Castillo, J.

    2011-01-01

    In this paper is described the dismantling a category I selfshielded gamma irradiation facility model MPX - γ - 25M. The following specific objectives were established: a) identify aspects of the insurance contract, human and technical resources b) assess the radiological situation of the process and c) analyze potential radiological extraordinary events in each step of the process, ensuring appropriate responses, based on an evaluation of process safety. The assessment of radiological events can serve as a reference for addressing the process of dismantling other similar irradiators. (Author)

  20. Polychlorinated biphenyls (PCBs) in the frame of the dismantling of nuclear facilities

    International Nuclear Information System (INIS)

    Hagenbart, Lars; Held, Christian; Reichert, Alexander

    2013-01-01

    During construction and maintenance of nuclear facilities PCB (polychlorinated biphenyls) containing paints were used in a large extent in the past. The WAK dismantling and disposal Company has dismantles such facilities and identified the PCB in the buildings. Besides the radionuclides the conventional hazardous material group of the PCBs has also to be disposed. The respective legal regulations have to be considered. In the frame of the contribution the radiological release of building structures with respect to re-use or demolition and residual PCB containing materials is discussed. The radiological disposal in final repositories and the conventional disposal regulations for releasable residual wastes are reported.

  1. Provision of the technical infrastructure for the dismantling of the WAK HAWC container. Design and realization

    International Nuclear Information System (INIS)

    Marquard, C.; Ripholz, M.; Lutz, W.

    2013-01-01

    The dismantling concept of the WAK HAWC (high-level liquid waste concentrate) containers includes remote handling equipment. Due to the solid deposits that formed during the concentrate storage time the activity and the dose rates of the containers are very high (2.6x10E15 Bq alpha and beta, dose rates higher 100 Sv/h). Therefore appropriate radiation protection measures have to be installed to protect personnel and environment. The provision of the technical infrastructure for the remote HAWC container dismantling is described in detail.

  2. Comparison of ship dismantling processes in India and the U.S.

    Science.gov (United States)

    Ahluwalia, Rashpal S.; Sibal, Pooja; Govindarajulu, Sriram

    2004-03-01

    This paper compares ship-dismantling processes in India and the U.S. The information for India was collected during an informal visit to the ship dismantling sites in Alang, India. The information for the U.S. was obtained from the MARAD report. For a 10,000-ton passenger ship, the Indian contractor makes a profit of about 24% compared to a loss of about 15% in the U.S. The loss in the US is primarily due to high labor costs, compliance to safety and health regulations and lack of market for used components and scrap metal.

  3. Health and Safety Considerations Associated with Sodium-Cooled Experimental Nuclear Fuel Dismantlement

    Energy Technology Data Exchange (ETDEWEB)

    Carvo, Alan E. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-04-01

    Between the mid-1970s and the mid-1980s Sandia National Laboratory constructed eleven experimental assemblies to simulate debris beds formed in a sodium-cooled fast breeder reactor. All but one of the assemblies were irradiated. The experimental assemblies were transferred to the Idaho National Laboratory (INL) in 2007 and 2008 for storage, dismantlement, recovery of the uranium for reuse in the nuclear fuel cycle, and disposal of unneeded materials. This paper addresses the effort to dismantle the assemblies down to the primary containment vessel and repackage them for temporary storage until such time as equipment necessary for sodium separation is in place.

  4. Dismantling of a hot cell of high level activity. Method and tools used

    International Nuclear Information System (INIS)

    Jeantet, E.; Miquel, P.; Baudoin, J.C.; Moutonnet, A.

    1981-05-01

    The aim of this operation is the removal of all the equipment and the material introduced and used in the hot cell 'Attila' and its decontamination to obtain an irradiation level as low as possible to allow direct intervention. The Attila facilitie was build in 1964-1966 to study dry processing of irradiated fuels by halogenide volatility process. Dismantling of the out-cell and of the laboratory associated to the shielded cell, dismantling inside the shielded cell with the remote handling equipment of the cell and tools used for these operations are described in this article [fr

  5. U P1, an example for advanced techniques applied to high level activity dismantling

    International Nuclear Information System (INIS)

    Michel-Noel, M.; Calixte, O.; Blanchard, S.; Bani, J.; Girones, P.; Moitrier, C.; Terry, G.; Bourdy, R.

    2014-01-01

    The U P1 plant on the CEA Marcoule site was dedicated to the processing of spend fuels from the G1, G2 and G3 plutonium-producing reactors. This plant represents 20.000 m 2 of workshops housing about 1000 hot cells. In 1998, a huge program for the dismantling and cleaning-up of the UP1 plant was launched. CEA has developed new techniques to face the complexity of the dismantling operations. These techniques include immersive virtual reality, laser cutting, a specific manipulator arm called MAESTRO and remote handling. (A.C.)

  6. Interaction of microtubules with active principles of Xanthium strumarium.

    Science.gov (United States)

    Menon, G S; Kuchroo, K; Dasgupta, D

    2001-01-01

    Indigenous variety of Xanthium strumarium (X. strumarium) was screened for its antimitotic activity using the microtubule-tubulin system isolated from mammalian tissue. A preliminary phytochemical screening of the whole extracts of the plant was carried out followed by partial purification of the whole extract of X.strumarium. The separated fractions obtained were identified and used for in vitro polymerization studies. The whole as well as partially separated chemical constituents of X. strumarium showed effective inhibition of tubulin polymerization. The results thus suggest that X. strumarium may possess antimitotic components.

  7. Genetic analysis of a Drosophila microtubule-associated protein

    OpenAIRE

    1992-01-01

    The 205-kD microtubule-associated protein (205K MAP) is one of the principal MAPs in Drosophila. 205K MAP is similar to the HeLa 210K/MAP4 family of MAPs since it shares the following biochemical properties: it is present in several isoforms, has a molecular mass of approximately 200 kD, and is thermostable. Furthermore, immuno-crossreactivity has been observed between mouse MAP4, HeLa 210K, and Drosophila 205K MAP. Currently, there is little information concerning the biological function of ...

  8. Dismantling Terrorism: Developing Actionable Solutions for Today's Plague of Violence

    National Research Council Canada - National Science Library

    Scott, Frances K

    2007-01-01

    .... The bibliography is divided into the following sections: causes and origins of terrorism, geographical distribution of terrorist groups, terrorist financing, terrorist groups and networks, the psychology of terrorism, prevention of terrorism, remedies...

  9. Application of an automatic yarn dismantler to track changes in cotton fibre properties during processing on a miniature spinning line

    CSIR Research Space (South Africa)

    Fassihi, A

    2014-11-01

    Full Text Available . The results obtained on different Upland cottons have clearly demonstrated the practical value of the yarn dismantler in enabling yarns to be automatically dismantled into their constituent fibres, which can then be tested by instrument, such as the AFIS...

  10. Experience of the remote dismantling of the Windscale advanced gas-cooled reactor and Windscale pile chimneys

    International Nuclear Information System (INIS)

    Wright, E.M.

    1993-01-01

    This paper gives brief descriptions of some of the remote dismantling work and equipment used on two large decommissioning projects: the BNFL Windscale Pile Chimneys Project (remote handling machine, waste packaging machine, remotely controlled excavator, remotely controlled demolition machine) and the AEA Windscale Advanced Gas-cooled Reactor Project (remote dismantling machine, operational waste, bulk removal techniques, semi-remote cutting operations)

  11. A methodology to simulate the cutting process for a nuclear dismantling simulation based on a digital manufacturing platform

    International Nuclear Information System (INIS)

    Hyun, Dongjun; Kim, Ikjune; Lee, Jonghwan; Kim, Geun-Ho; Jeong, Kwan-Seong; Choi, Byung Seon; Moon, Jeikwon

    2017-01-01

    Highlights: • Goal is to provide existing tech. with cutting function handling dismantling process. • Proposed tech. can handle various cutting situations in the dismantlement activities. • Proposed tech. can be implemented in existing graphical process simulation software. • Simulation results have demonstrated that the proposed technology achieves its goal. • Proposed tech. enlarges application of graphic simulation into dismantlement activity. - Abstract: This study proposes a methodology to simulate the cutting process in a digital manufacturing platform for the flexible planning of nuclear facility decommissioning. During the planning phase of decommissioning, visualization and verification using process simulation can be powerful tools for the flexible planning of the dismantling process of highly radioactive, large and complex nuclear facilities. However, existing research and commercial solutions are not sufficient for such a situation because complete segmented digital models for the dismantling objects such as the reactor vessel, internal assembly, and closure head must be prepared before the process simulation. The preparation work has significantly impeded the broad application of process simulation due to the complexity and workload. The methodology of process simulation proposed in this paper can flexibly handle various dismantling processes including repetitive object cuttings over heavy and complex structures using a digital manufacturing platform. The proposed methodology, which is applied to dismantling scenarios of a Korean nuclear power plant in this paper, is expected to reduce the complexity and workload of nuclear dismantling simulations.

  12. The PCR (Prévessin Control Room), scene of some of the greatest moments in CERN's history, is being dismantled to prepare for a complete overhaul.

    CERN Multimedia

    Maximilien Brice

    2004-01-01

    Removal manager Claes Frisk (right on picture 02) in the almost entirely dismantled PCR, together with René Ballet, who installed the racks in the 1970s and today is responsible for dismantling them.

  13. Biallelic Mutations in TBCD, Encoding the Tubulin Folding Cofactor D, Perturb Microtubule Dynamics and Cause Early-Onset Encephalopathy

    NARCIS (Netherlands)

    Flex, Elisabetta; Niceta, Marcello; Cecchetti, Serena; Thiffault, Isabelle; Au, Margaret G.; Capuano, Alessandro; Piermarini, Emanuela; Ivanova, Anna A.; Francis, Joshua W.; Chillemi, Giovanni; Chandramouli, Balasubramanian; Carpentieri, Giovanna; Haaxma, Charlotte A.; Ciolfi, Andrea; Pizzi, Simone; Douglas, Ganka V.; Levine, Kara; Sferra, Antonella; Dentici, Maria Lisa; Pfundt, Rolph R.; Le Pichon, Jean-Baptiste; Farrow, Emily; Baas, Frank; Piemonte, Fiorella; Dallapiccola, Bruno; Graham, John M.; Saunders, Carol J.; Bertini, Enrico; Kahn, Richard A.; Koolen, David A.; Tartaglia, Marco

    2016-01-01

    Microtubules are dynamic cytoskeletal elements coordinating and supporting a variety of neuronal processes, including cell division, migration, polarity, intracellular trafficking, and signal transduction. Mutations in genes encoding tubulins and microtubule-associated proteins are known to cause

  14. A ROP2-RIC1 pathway fine-tunes microtubule reorganization for salt tolerance in Arabidopsis.

    Science.gov (United States)

    Li, Changjiang; Lu, Hanmei; Li, Wei; Yuan, Ming; Fu, Ying

    2017-07-01

    The reorganization of microtubules induced by salt stress is required for Arabidopsis survival under high salinity conditions. RIC1 is an effector of Rho-related GTPase from plants (ROPs) and a known microtubule-associated protein. In this study, we demonstrated that RIC1 expression decreased with long-term NaCl treatment, and ric1-1 seedlings exhibited a higher survival rate under salt stress. We found that RIC1 reduced the frequency of microtubule transition from shortening to growing status and knockout of RIC1 improved the reassembly of depolymerized microtubules caused by either oryzalin treatment or salt stress. Further investigation showed that constitutively active ROP2 promoted the reassembly of microtubules and the survival of seedlings under salt stress. A rop2-1 ric1-1 double mutant rescued the salt-sensitive phenotype of rop2-1, indicating that ROP2 functions in salt tolerance through RIC1. Although ROP2 did not regulate RIC1 expression upon salt stress, a quick but mild increase of ROP2 activity was induced, led to reduction of RIC1 on microtubules. Collectively, our study reveals an ROP2-RIC1 pathway that fine-tunes microtubule dynamics in response to salt stress in Arabidopsis. This finding not only reveals a new regulatory mechanism for microtubule reorganization under salt stress but also the importance of ROP signalling for salinity tolerance. © 2017 John Wiley & Sons Ltd.

  15. Stable and dynamic microtubules coordinately shape the myosin activation zone during cytokinetic furrow formation

    Science.gov (United States)

    Foe, Victoria E.; von Dassow, George

    2008-01-01

    The cytokinetic furrow arises from spatial and temporal regulation of cortical contractility. To test the role microtubules play in furrow specification, we studied myosin II activation in echinoderm zygotes by assessing serine19-phosphorylated regulatory light chain (pRLC) localization after precisely timed drug treatments. Cortical pRLC was globally depressed before cytokinesis, then elevated only at the equator. We implicated cell cycle biochemistry (not microtubules) in pRLC depression, and differential microtubule stability in localizing the subsequent myosin activation. With no microtubules, pRLC accumulation occurred globally instead of equatorially, and loss of just dynamic microtubules increased equatorial pRLC recruitment. Nocodazole treatment revealed a population of stable astral microtubules that formed during anaphase; among these, those aimed toward the equator grew longer, and their tips coincided with cortical pRLC accumulation. Shrinking the mitotic apparatus with colchicine revealed pRLC suppression near dynamic microtubule arrays. We conclude that opposite effects of stable versus dynamic microtubules focuses myosin activation to the cell equator during cytokinesis. PMID:18955555

  16. Microtubule reorganization in tobacco BY-2 cells stably expressing GFP-MBD

    Science.gov (United States)

    Granger, C. L.; Cyr, R. J.

    2000-01-01

    Microtubule organization plays an important role in plant morphogenesis; however, little is known about how microtubule arrays transit from one organized state to another. The use of a genetically incorporated fluorescent marker would allow long-term observation of microtubule behavior in living cells. Here, we have characterized a Nicotiana tabacum L. cv. Bright Yellow 2 (BY-2) cell line that had been stably transformed with a gfp-mbd construct previously demonstrated to label microtubules (J. Marc et al., 1998, Plant Cell 10: 1927-1939). Fluorescence levels were low, but interphase and mitotic microtubule arrays, as well as the transitions between these arrays, could be observed in individual gfp-mbd-transformed cells. By comparing several attributes of transformed and untransformed cells it was concluded that the transgenic cells are not adversely affected by low-level expression of the transgene and that these cells will serve as a useful and accurate model system for observing microtubule reorganization in vivo. Indeed, some initial observations were made that are consistent with the involvement of motor proteins in the transition between the spindle and phragmoplast arrays. Our observations also support the role of the perinuclear region in nucleating microtubules at the end of cell division with a progressive shift of these microtubules and/or nucleating activity to the cortex to form the interphase cortical array.

  17. Four-stranded mini microtubules formed by Prosthecobacter BtubAB show dynamic instability.

    Science.gov (United States)

    Deng, Xian; Fink, Gero; Bharat, Tanmay A M; He, Shaoda; Kureisaite-Ciziene, Danguole; Löwe, Jan

    2017-07-18

    Microtubules, the dynamic, yet stiff hollow tubes built from αβ-tubulin protein heterodimers, are thought to be present only in eukaryotic cells. Here, we report a 3.6-Å helical reconstruction electron cryomicroscopy structure of four-stranded mini microtubules formed by bacterial tubulin-like Prosthecobacter dejongeii BtubAB proteins. Despite their much smaller diameter, mini microtubules share many key structural features with eukaryotic microtubules, such as an M-loop, alternating subunits, and a seam that breaks overall helical symmetry. Using in vitro total internal reflection fluorescence microscopy, we show that bacterial mini microtubules treadmill and display dynamic instability, another hallmark of eukaryotic microtubules. The third protein in the btub gene cluster, BtubC, previously known as "bacterial kinesin light chain," binds along protofilaments every 8 nm, inhibits BtubAB mini microtubule catastrophe, and increases rescue. Our work reveals that some bacteria contain regulated and dynamic cytomotive microtubule systems that were once thought to be only useful in much larger and sophisticated eukaryotic cells.

  18. Synthesis and biological evaluation of structurally simplified noscapine analogues as microtubule binding agents

    Czech Academy of Sciences Publication Activity Database

    Ghaly, P.E.; Churchill, C.D.M.; Abou El-Magd, R.M.; Hájková, Zuzana; Dráber, Pavel; West, F.G.; Tuszyński, J.A.

    2017-01-01

    Roč. 95, č. 6 (2017), s. 649-655 ISSN 0008-4042 R&D Projects: GA ČR GA15-22194S Institutional support: RVO:68378050 Keywords : noscapine * microtubule * tubulin * cytotoxicity * microtubule dynamics * docking Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 1.080, year: 2016

  19. Dietary flavonoid fisetin binds to β-tubulin and disrupts microtubule dynamics in prostate cancer cells.

    Science.gov (United States)

    Mukhtar, Eiman; Adhami, Vaqar Mustafa; Sechi, Mario; Mukhtar, Hasan

    2015-10-28

    Microtubule targeting based therapies have revolutionized cancer treatment; however, resistance and side effects remain a major limitation. Therefore, novel strategies that can overcome these limitations are urgently needed. We made a novel discovery that fisetin, a hydroxyflavone, is a microtubule stabilizing agent. Fisetin binds to tubulin and stabilizes microtubules with binding characteristics far superior than paclitaxel. Surface plasmon resonance and computational docking studies suggested that fisetin binds to β-tubulin with superior affinity compared to paclitaxel. Fisetin treatment of human prostate cancer cells resulted in robust up-regulation of microtubule associated proteins (MAP)-2 and -4. In addition, fisetin treated cells were enriched in α-tubulin acetylation, an indication of stabilization of microtubules. Fisetin significantly inhibited PCa cell proliferation, migration, and invasion. Nudc, a protein associated with microtubule motor dynein/dynactin complex that regulates microtubule dynamics, was inhibited with fisetin treatment. Further, fisetin treatment of a P-glycoprotein overexpressing multidrug-resistant cancer cell line NCI/ADR-RES inhibited the viability and colony formation. Our results offer in vitro proof-of-concept for fisetin as a microtubule targeting agent. We suggest that fisetin could be developed as an adjuvant for treatment of prostate and other cancer types. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  20. Expansion and Polarity Sorting in Microtubule-Dynein Bundles(WHAT IS LIFE? THE NEXT 100 YEARS OF YUKAWA'S DREAM)

    OpenAIRE

    Assaf, ZEMEL; Alex, MOGILNER; Department of Neurobiology, Physiology and Behavior, University of California; Department of Neurobiology, Physiology and Behavior, University of California

    2008-01-01

    Interactions of multiple molecular motors with dynamic polymers, such as actin and microtubules, form the basis for many processes in the cell cytoskeleton. One example is the active 'sorting' of microtubule bundles by dynein molecular motors into aster-like arrays of microtubules; in these bundles dynein motors cross-link and slide neighboring microtubules apart. A number of models have been suggested to quantify the active dynamics of cross-linked bundles of polar filaments. In the case of ...

  1. Visualization of a dismantling environment for an evaluation of a worker's dose during the decommissioning of KRR-1 and 2

    International Nuclear Information System (INIS)

    Park, Hee Seong; Kim, Sung Kyun; Lee, Kune Woo; Jung, Chong Hun; Jin, Seong Il

    2008-01-01

    The purpose of this paper is to provide a basis for an optimization of a dismantling process of a research reactor and nuclear facility. An optimization of a dismantling process should be at the beginning of a study for an evaluation of the radioactivity inventory and the safety of the workers. Many countries have conducted an optimization to achieve a shortened dismantling schedule, a reduction of the amount of waste, and cut down on the decommissioning by using computer graphics such as animation, simulation, and virtual reality. In the present study, we propose methods for identifying the existence of radioactivity which is contained in the dismantled objects and for evaluating a worker's dose through a simulation. To evaluate a worker's external dose under a virtual dismantling environment generated by computer graphics, the shape of the thermal column horizontal door was created by 3D CAD and the radiation dose surrounding the door was calculated by using MCNP-4C. An animation that can demonstrate a dismantling procedure according to a dismantling scenario was produced. For matching the radiation dose, which was calculated by MCNP-4C with an area where workers are dismantling a door, a simulation module was developed which could show a worker's external dose in real-time. The result from the distribution of the radioactivity enables us to specify where the most contaminated part of the dismantling objects is. In the animation, a virtual worker demonstrated a dismantling activity procedure as a chosen scenario. In the simulation, a worker's exposure dose rate in real-time has been evaluated

  2. Kindlin1 regulates microtubule function to ensure normal mitosis.

    Science.gov (United States)

    Patel, Hitesh; Stavrou, Ifigeneia; Shrestha, Roshan L; Draviam, Viji; Frame, Margaret C; Brunton, Valerie G

    2016-08-01

    Loss of Kindlin 1 (Kin1) results in the skin blistering disorder Kindler Syndrome (KS), whose symptoms also include skin atrophy and reduced keratinocyte proliferation. Kin1 binds to integrins to modulate their activation and more recently it has been shown to regulate mitotic spindles and cell survival in a Plk1-dependent manner. Here we report that short-term Kin1 deletion in mouse skin results in impaired mitosis, which is associated with reduced acetylated tubulin (ac-tub) levels and cell proliferation. In cells, impaired mitosis and reduced ac-tub levels are also accompanied by reduced microtubule stability, all of which are rescued by HDAC6 inhibition. The ability of Kin1 to regulate HDAC6-dependent cellular ac-tub levels is dependent on its phosphorylation by Plk1. Taken together, these data define a novel role for Kin1 in microtubule acetylation and stability and offer a mechanistic insight into how certain KS phenotypes, such as skin atrophy and reduced cell proliferation, arise. © The Author (2016). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, IBCB, SIBS, CAS.

  3. Hepatocyte cotransport of taurocholate and bilirubin glucuronides: Role of microtubules

    International Nuclear Information System (INIS)

    Crawford, J.M.; Gollan, J.L.

    1988-01-01

    Modulation of bile pigment excretion by bile salts has been attributed to modification of canalicular membrane transport or a physical interaction in bile. Based on the observation that a microtubule-dependent pathway is involved in the hepatocellular transport of bile salts, the authors investigated the possibility that bilirubin glucuronides are associated with bile salts during intracellular transport. Experiments were conducted in intact rats (basal) or after overnight biliary diversion and intravenous reinfusion of taurocholate (depleted/reinfused). All rats were pretreated with intravenous low-dose colchicine or its inactive isomer lumicolchicine. Biliary excretion of radiolabeled bilirubin glucuronides derived from tracer [ 14 C]bilirubin-[ 3 H]bilirubin monoglucuronide (coinjected iv) was unchanged in basal rats but was consistently delayed in depleted/reinfused rats. This was accompanied by a significant shift toward bilirubin diglucuronide formation from both substrates. In basal Gunn rats, with deficient bilirubin glucuronidation, biliary excretion of intravenous [ 14 C]bilirubin monoglucuronide-[ 3 H]bilirubin diglucuronide was unaffected by colchicine but was retarded in depleted/reinfused Gunn rats. Colchicine had no effect on the rate of bilirubin glucuronidation in vitro in rat liver microsomes. They conclude that a portion of the bilirubin glucuronides generated endogenously in hepatocytes or taken up directly from plasma may be cotransported with bile salts to the bile canalicular membrane via a microtubule-dependent mechanism

  4. Spatiotemporal Regulation of Nuclear Transport Machinery and Microtubule Organization

    Science.gov (United States)

    Okada, Naoyuki; Sato, Masamitsu

    2015-01-01

    Spindle microtubules capture and segregate chromosomes and, therefore, their assembly is an essential event in mitosis. To carry out their mission, many key players for microtubule formation need to be strictly orchestrated. Particularly, proteins that assemble the spindle need to be translocated at appropriate sites during mitosis. A small GTPase (hydrolase enzyme of guanosine triphosphate), Ran, controls this translocation. Ran plays many roles in many cellular events: nucleocytoplasmic shuttling through the nuclear envelope, assembly of the mitotic spindle, and reorganization of the nuclear envelope at the mitotic exit. Although these events are seemingly distinct, recent studies demonstrate that the mechanisms underlying these phenomena are substantially the same as explained by molecular interplay of the master regulator Ran, the transport factor importin, and its cargo proteins. Our review focuses on how the transport machinery regulates mitotic progression of cells. We summarize translocation mechanisms governed by Ran and its regulatory proteins, and particularly focus on Ran-GTP targets in fission yeast that promote spindle formation. We also discuss the coordination of the spatial and temporal regulation of proteins from the viewpoint of transport machinery. We propose that the transport machinery is an essential key that couples the spatial and temporal events in cells. PMID:26308057

  5. Microtubules Nonlinear Models Dynamics Investigations through the exp(−Φ(ξ-Expansion Method Implementation

    Directory of Open Access Journals (Sweden)

    Nur Alam

    2016-02-01

    Full Text Available In this research article, we present exact solutions with parameters for two nonlinear model partial differential equations(PDEs describing microtubules, by implementing the exp(−Φ(ξ-Expansion Method. The considered models, describing highly nonlinear dynamics of microtubules, can be reduced to nonlinear ordinary differential equations. While the first PDE describes the longitudinal model of nonlinear dynamics of microtubules, the second one describes the nonlinear model of dynamics of radial dislocations in microtubules. The acquired solutions are then graphically presented, and their distinct properties are enumerated in respect to the corresponding dynamic behavior of the microtubules they model. Various patterns, including but not limited to regular, singular kink-like, as well as periodicity exhibiting ones, are detected. Being the method of choice herein, the exp(−Φ(ξ-Expansion Method not disappointing in the least, is found and declared highly efficient.

  6. Centriole triplet microtubules are required for stable centriole formation and inheritance in human cells

    Science.gov (United States)

    Wang, Jennifer T; Kong, Dong; Hoerner, Christian R; Loncarek, Jadranka

    2017-01-01

    Centrioles are composed of long-lived microtubules arranged in nine triplets. However, the contribution of triplet microtubules to mammalian centriole formation and stability is unknown. Little is known of the mechanism of triplet microtubule formation, but experiments in unicellular eukaryotes indicate that delta-tubulin and epsilon-tubulin, two less-studied tubulin family members, are required. Here, we report that centrioles in delta-tubulin and epsilon-tubulin null mutant human cells lack triplet microtubules and fail to undergo centriole maturation. These aberrant centrioles are formed de novo each cell cycle, but are unstable and do not persist to the next cell cycle, leading to a futile cycle of centriole formation and disintegration. Disintegration can be suppressed by paclitaxel treatment. Delta-tubulin and epsilon-tubulin physically interact, indicating that these tubulins act together to maintain triplet microtubules and that these are necessary for inheritance of centrioles from one cell cycle to the next. PMID:28906251

  7. Centriole triplet microtubules are required for stable centriole formation and inheritance in human cells.

    Science.gov (United States)

    Wang, Jennifer T; Kong, Dong; Hoerner, Christian R; Loncarek, Jadranka; Stearns, Tim

    2017-09-14

    Centrioles are composed of long-lived microtubules arranged in nine triplets. However, the contribution of triplet microtubules to mammalian centriole formation and stability is unknown. Little is known of the mechanism of triplet microtubule formation, but experiments in unicellular eukaryotes indicate that delta-tubulin and epsilon-tubulin, two less-studied tubulin family members, are required. Here, we report that centrioles in delta-tubulin and epsilon-tubulin null mutant human cells lack triplet microtubules and fail to undergo centriole maturation. These aberrant centrioles are formed de novo each cell cycle, but are unstable and do not persist to the next cell cycle, leading to a futile cycle of centriole formation and disintegration. Disintegration can be suppressed by paclitaxel treatment. Delta-tubulin and epsilon-tubulin physically interact, indicating that these tubulins act together to maintain triplet microtubules and that these are necessary for inheritance of centrioles from one cell cycle to the next.

  8. TONNEAU2/FASS Regulates the Geometry of Microtubule Nucleation and Cortical Array Organization in Interphase Arabidopsis Cells[C][W

    Science.gov (United States)

    Kirik, Angela; Ehrhardt, David W.; Kirik, Viktor

    2012-01-01

    Organization of microtubules into ordered arrays involves spatial and temporal regulation of microtubule nucleation. Here, we show that acentrosomal microtubule nucleation in plant cells involves a previously unknown regulatory step that determines the geometry of microtubule nucleation. Dynamic imaging of interphase cortical microtubules revealed that the ratio of branching to in-bundle microtubule nucleation on cortical microtubules is regulated by the Arabidopsis thaliana B′′ subunit of protein phosphatase 2A, which is encoded by the TONNEAU2/FASS (TON2) gene. The probability of nucleation from γ-tubulin complexes localized at the cell cortex was not affected by a loss of TON2 function, suggesting a specific role of TON2 in regulating the nucleation geometry. Both loss of TON2 function and ectopic targeting of TON2 to the plasma membrane resulted in defects in cell shape, suggesting the importance of TON2-mediated regulation of the microtubule cytoskeleton in cell morphogenesis. Loss of TON2 function also resulted in an inability for cortical arrays to reorient in response to light stimulus, suggesting an essential role for TON2 and microtubule branching nucleation in reorganization of microtubule arrays. Our data establish TON2 as a regulator of interphase microtubule nucleation and provide experimental evidence for a novel regulatory step in the process of microtubule-dependent nucleation. PMID:22395485

  9. Wood cell-wall structure requires local 2D-microtubule disassembly by a novel plasma membrane-anchored protein.

    Science.gov (United States)

    Oda, Yoshihisa; Iida, Yuki; Kondo, Yuki; Fukuda, Hiroo

    2010-07-13

    Plant cells have evolved cortical microtubules, in a two-dimensional space beneath the plasma membrane, that regulate patterning of cellulose deposition. Although recent studies have revealed that several microtubule-associated proteins facilitate self-organization of transverse cortical microtubules, it is still unknown how diverse patterns of cortical microtubules are organized in different xylem cells, which are the major components of wood. Using our newly established in vitro xylem cell differentiation system, we found that a novel microtubule end-tracking protein, microtubule depletion domain 1 (MIDD1), was anchored to distinct plasma membrane domains and promoted local microtubule disassembly, resulting in pits on xylem cell walls. The introduction of RNA interference for MIDD1 resulted in the failure of local microtubule depletion and the formation of secondary walls without pits. Conversely, the overexpression of MIDD1 reduced microtubule density. MIDD1 has two coiled-coil domains for the binding to microtubules and for the anchorage to plasma membrane domains, respectively. Combination of the two coils caused end tracking of microtubules during shrinkage and suppressed their rescue events. Our results indicate that MIDD1 integrates spatial information in the plasma membrane with cortical microtubule dynamics for determining xylem cell wall pattern. Copyright 2010 Elsevier Ltd. All rights reserved.

  10. Interactive domains in the molecular chaperone human alphaB crystallin modulate microtubule assembly and disassembly.

    Directory of Open Access Journals (Sweden)

    Joy G Ghosh

    2007-06-01

    Full Text Available Small heat shock proteins regulate microtubule assembly during cell proliferation and in response to stress through interactions that are poorly understood.Novel functions for five interactive sequences in the small heat shock protein and molecular chaperone, human alphaB crystallin, were investigated in the assembly/disassembly of microtubules and aggregation of tubulin using synthetic peptides and mutants of human alphaB crystallin.The interactive sequence (113FISREFHR(120 exposed on the surface of alphaB crystallin decreased microtubule assembly by approximately 45%. In contrast, the interactive sequences, (131LTITSSLSSDGV(142 and (156ERTIPITRE(164, corresponding to the beta8 strand and the C-terminal extension respectively, which are involved in complex formation, increased microtubule assembly by approximately 34-45%. The alphaB crystallin peptides, (113FISREFHR(120 and (156ERTIPITRE(164, inhibited microtubule disassembly by approximately 26-36%, and the peptides (113FISREFHR(120 and (131LTITSSLSSDGV(142 decreased the thermal aggregation of tubulin by approximately 42-44%. The (131LTITSSLSSDGV(142 and (156ERTIPITRE(164 peptides were more effective than the widely used anti-cancer drug, Paclitaxel, in modulating tubulinmicrotubule dynamics. Mutagenesis of these interactive sequences in wt human alphaB crystallin confirmed the effects of the alphaB crystallin peptides on microtubule assembly/disassembly and tubulin aggregation. The regulation of microtubule assembly by alphaB crystallin varied over a narrow range of concentrations. The assembly of microtubules was maximal at alphaB crystallin to tubulin molar ratios between 1:4 and 2:1, while molar ratios >2:1 inhibited microtubule assembly.Interactive sequences on the surface of human alphaB crystallin collectively modulate microtubule assembly through a dynamic subunit exchange mechanism that depends on the concentration and ratio of alphaB crystallin to tubulin. These are the first

  11. Remotely-Controlled Shear for Dismantling Highly Radioactive Tools In Rokkasho Vitrification Facility - 12204

    Energy Technology Data Exchange (ETDEWEB)

    Mitsui, Takashi; Sawa, Shusuke; Sadaki, Akira; Awano, Toshihiko [IHI Corporation, 1 Shin-Nakahara-cho, Isogo-ku, Yokohama, Kanagawa (Japan); Cole, Matt [S.A. Technology Inc, 3985 S. Lincoln Ave., Ste. 100, Loveland CO 80537 (United States); Miura, Yasuhiko; Ino, Tooru [Japan Nuclear Fuel Limited, 4-108, Aza Okitsuke, Oaza Obuchi, Rokkasho-Mura, Kamikita-gun, Aomori (Japan)

    2012-07-01

    A high-level liquid waste vitrification facility in the Japanese Rokkasho Reprocessing Plant (RRP) is right in the middle of hot commissioning tests toward starting operation in fall of 2012. In these tests, various tools were applied to address issues occurring in the vitrification cell. Because of these tools' unplanned placement in the cell it has been necessary to dismantle and dispose of them promptly. One of the tools requiring removal is a rod used in the glass melter to improve glass pouring. It is composed of a long rod made of Inconel 601 or 625 and has been highly contaminated. In order to dismantle these tools and to remotely put them in a designated waste basket, a custom electric shear machine was developed. It was installed in a dismantling area of the vitrification cell by remote cranes and manipulators and has been successfully operated. It can be remotely dismantled and placed in a waste basket for interim storage. This is a very good example of a successful deployment of a specialty remote tool in a hot cell environment. This paper also highlights how commissioning and operations are done in the Japanese Rokkasho Reprocessing Plant. (authors)

  12. Installation dismantling system, working process and hood utilizable in this system

    International Nuclear Information System (INIS)

    Poirier, J.C.; Mulcey, P.; Morel, P.; Vavasseur, C.

    1989-01-01

    The system for dismantling an installation under a controlled atmosphere is made by a tool polluting the atmosphere, a gas blanket creating a continement zone around the tool, an extractor removing polluted gas from the zone, a purifier for the extracted gas and a controller regulating the flow of gas in the blanket and keeping the installation at constant pressure [fr

  13. ''1995/2010: site drainage and nuclear facilities dismantling program'' result 2001

    International Nuclear Information System (INIS)

    2001-01-01

    A drainage and dismantling planing with the corresponding wastes management, has been decided for the CEA of Fontenay aux roses, in 1995. It will end in 2010. This document presents the main evolutions occurred since october 2000. (A.L.B.)

  14. The dismantling of nuclear power plants which are not in use

    International Nuclear Information System (INIS)

    Tanguy, P.

    1987-01-01

    At the end of its life span, a nuclear power plant contains big quantities of radioactive products. The corresponding risks must be controlled and over the long range, all radioactivity must be definitively removed. The latter operation is called dismantling. In France, at the beginning of 1987, five nuclear units which were permanently put out of use have to be dismantled. These units are presented in this article. From this presentation, it can be seen that there are now techniques which provide for complete control of the risks corresponding to radioactivity. However, in France, as in the rest of the world, the dismantling of nuclear plants will not attain its full industrial level until the 21st Century. The problems which have to be solved are known, but better performing technologies have to be developed in order to obtain a superior protection of dismantling work crews and a reduction of costs. This article concludes with an appeal for high French interest in international activities in this field [fr

  15. Sustainable design for automotive products: dismantling and recycling of end-of-life vehicles.

    Science.gov (United States)

    Tian, Jin; Chen, Ming

    2014-02-01

    The growth in automotive production has increased the number of end-of-life vehicles (ELVs) annually. The traditional approach ELV processing involves dismantling, shredding, and landfill disposal. The "3R" (i.e., reduce, reuse, and recycle) principle has been increasingly employed in processing ELVs, particularly ELV parts, to promote sustainable development. The first step in processing ELVs is dismantling. However, certain parts of the vehicle are difficult to disassemble and use in practice. The extended producer responsibility policy requires carmakers to contribute in the processing of scrap cars either for their own developmental needs or for social responsibility. The design for dismantling approach can be an effective solution to the existing difficulties in dismantling ELVs. This approach can also provide guidelines in the design of automotive products. This paper illustrates the difficulty of handling polymers in dashboards. The physical properties of polymers prevent easy separation and recycling by using mechanical methods. Thus, dealers have to rely on chemical methods such as pyrolysis. Therefore, car designers should use a single material to benefit dealers. The use of materials for effective end-of-life processing without sacrificing the original performance requirements of the vehicle should be explored. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Pick-N-Pull Auto Dismantlers, Kansas City, LLC Inc. - Clean Water Act Public Notice

    Science.gov (United States)

    The EPA is providing notice of a proposed Administrative Penalty Assessment against Pick-N-Pull Auto Dismantlers, Kansas City, LLC, a subsidiary of Schnitzer Steel Industries, Inc., for alleged violations at its facilities at 8012 East Truman Rd., Kansas C

  17. Dismantling of JPDR reactor internals by underwater plasma arc cutting technique using robotic manipulator

    International Nuclear Information System (INIS)

    Yokota, M.

    1988-01-01

    The actual dismantling of JPDR started on December 4, 1986. As of now, equipment that surrounds the reactor has mostly been removed to provide working space in reactor containment prior to the dismantling of reactor internals. Some reactor internals have been successfully dismantled using the underwater arc cutting system with a robotic manipulator during the period of January to March 1988. The cutting system is composed of an underwater plasma arc cutting device and a robotic manipulator. The cut off reactor internals were core spray block, feedwater sparger and stabilizers for fuel upper grid tube. The plasma arc cutting device was developed to dismantle the reactor internals underwater. It mainly consists of a plasma torch, power and gas supply systems for the torch, and by-product treatment systems. It has the cutting ability of 130 mm thickness stainless steel underwater. The robotic manipulator has seven degrees of freedom of movement, enabling it to move in almost the same way as the arm of a human being. The arm of the robot is mounted on a supporting device which is suspended by three chains from the support structure set on a service floor. A plasma torch is griped by the robotic hand; its position to the structure to be cut is controlled from a remote control room, about 100 meters outside the reactor containment

  18. Development of plasma arc cutting technique for dismantlement of reactor internals in JPDR decommissioning program

    International Nuclear Information System (INIS)

    Yanagihara, Satoshi; Tanaka, Mitsugu; Ujihara, Norio.

    1988-01-01

    The decommissioning program for JPDR has been conducted by JAERI since 1981 under contact with the Science and Technology Agency of Japan. The development of cutting tools for dismantling the JPDR is one of the important items in the program. An underwater plasma arc cutting technique was selected for dismantling the JPDR core internals. The study was concentrated on improving the cutting ability in water. Various cutting tests were conducted changing the parameters such as arc current, supply gas and cutting speed to evaluate the most effective cutting condition. Through the study, it has been achieved to be able to cut a 130 mm thick stainless steel plate in water. In addition, the amount and the characteristics of by-products were measured during the cutting tests for the safety evaluation of the dismantling activities. Final cutting tests and checkout of whole plasma arc cutting system were conducted using a mockup water pool and test pieces simulating the JPDR core internals. It was proved from the tests that the cutting system developed in the program will be applicable for the JPDR core internals dismantlement. (author)

  19. The concepts of the 'factory of the future' applied to cleanup and dismantling works

    International Nuclear Information System (INIS)

    Ghiban, A.; Girones, P.; Moitrier, C.; Gouhier, E.; Torreblanca, L.

    2016-01-01

    The 'factory of the future' relies on the implementation of new concepts and technologies like: connected robots, data analysis, virtual reality or enhanced reality in the fabrication processes. The article describes how these concepts can be used in cleanup or dismantling works. Both activities can be considered as the fabrication of a waste package and the processing plant as a factory. (A.C.)

  20. Adaptation of high pressure water jets with abrasives for nuclear installations dismantling

    International Nuclear Information System (INIS)

    Rouviere, R.; Pinault, M.; Gasc, B.; Guiadeur, R.; Pilot, M.

    1989-01-01

    This report presents the work realized for adjust the cutting technology with high pressure water jet with abrasives for nuclear installation dismantling. It has necessited the conception and the adjustement of a remote tool and the realization of cutting tests with waste produce analysis. This technic can be ameliorated with better viewing systems and better fog suction systems

  1. Cold trap dismantling and sodium removal at a fast breeder reactor

    Energy Technology Data Exchange (ETDEWEB)

    Graf, Anja; Petrick, Holger; Stutz, Uwe [WAK GmbH, Eggenstein-Leopoldshafen (Germany). Hauptabt. Dekontaminationsbetriebe Rueckbau Kompakte Natriumgekuehlte Kernreaktoranlage (KNK); Hosking, Paul [Nuclear Decommissioning Services Limited (NDSL), Sutherland, Dornoch (United Kingdom)

    2013-11-15

    The first German prototype Fast Breeder Nuclear Reactor (KNK) is currently being dismantled after being the only operating Fast Breeder-type reactor in Germany. As this reactor type used sodium as a coolant in its primary and secondary circuit, 7 cold traps containing various amounts of partially activated sodium needed to be disposed of as part of the dismantling. The resulting combined difficulties of radioactive contamination and high chemical reactivity were handled by treating the cold traps differently depending on their size and the amount of sodium contained inside. Six small cold traps were processed on-site by cutting them up into small parts using a band saw under a protective atmosphere. The sodium was then converted to sodium hydroxide by using water. The remaining large cold trap could not be handled in the same way due to its dimensions (2.9 m x 1.1 m) and the declared amount of sodium inside (1,700 kg). It was therefore manually dismantled inside a large box filled with a protective atmosphere, while the resulting pieces were packaged for later burning in a special facility. The experiences gained by KNK during this process may be advantageous for future dismantling projects in similar sodium-cooled reactors worldwide. (orig.)

  2. Quantity assessment of waste in the dismantlement of liquid waste treatment plant and its actual state

    International Nuclear Information System (INIS)

    Uchiyama, Takafumi; Mitsuhashi, Ishi; Matsumoto, Tetsuo; Morishima, Kayoko; Tanzawa, Tomio

    2016-01-01

    From the progress of decommissioning project work of Tokyo City University Atomic Energy Research Institute, this paper reports the comparison between the actual amount of the waste generated during dismantlement work at liquid waste treatment facilities and the assessment quantity before starting the dismantlement. The quantity assessment was made on the basis of the installation license application, design specifications, drawings, records, history of use, site investigation results, etc. Since this quantity assessment did not take into account the dismantling contents of reservoir concrete, the assessed quantity of non-radioactive waste (NR waste) did not match the sum of actual NR waste. However, if an actually generated quantity of concrete of radioactive waste was added to the quantity assessment as NR waste, the quantity of actually generated NR waste and that of assessed NR waste were nearly consistent, which verified the validity of this assessment. This method is considered to be able to be utilized in the future quantity assessment of decommissioning work and the like. On the other hand, it was found that the number of drums that were actually stored tended to increase more than the estimated number of drum conversion. In old buildings, it is necessary to take into account the generation of waste other than radioactive materials in the quantity assessment stage and dismantlement stage. (A.O.)

  3. Dismantling the dwelling : A systematic approach to investigating the meaning of the dwelling: draft

    NARCIS (Netherlands)

    Meesters, J.; Coolen, H.C.C.H.

    2009-01-01

    The meaning of the dwelling consists of multiple layers, which makes it a complex concept. Therefore it should be dismantled (ref. Rapoport, 2001). This paper presents a conceptual framework in which settings, activities and values are systematically related. The data is derived from a telephone

  4. Scoulerine affects microtubule structure, inhibits proliferation, arrests cell cycle and thus culminates in the apoptotic death of cancer cells.

    Science.gov (United States)

    Habartova, Klara; Havelek, Radim; Seifrtova, Martina; Kralovec, Karel; Cahlikova, Lucie; Chlebek, Jakub; Cermakova, Eva; Mazankova, Nadezda; Marikova, Jana; Kunes, Jiri; Novakova, Lucie; Rezacova, Martina

    2018-03-19

    Scoulerine is an isoquinoline alkaloid, which indicated promising suppression of cancer cells growth. However, the mode of action (MOA) remained unclear. Cytotoxic and antiproliferative properties were determined in this study. Scoulerine reduces the mitochondrial dehydrogenases activity of the evaluated leukemic cells with IC 50 values ranging from 2.7 to 6.5 µM. The xCELLigence system revealed that scoulerine exerted potent antiproliferative activity in lung, ovarian and breast carcinoma cell lines. Jurkat and MOLT-4 leukemic cells treated with scoulerine were decreased in proliferation and viability. Scoulerine acted to inhibit proliferation through inducing G2 or M-phase cell cycle arrest, which correlates well with the observed breakdown of the microtubule network, increased Chk1 Ser345, Chk2 Thr68 and mitotic H3 Ser10 phosphorylation. Scoulerine was able to activate apoptosis, as determined by p53 upregulation, increase caspase activity, Annexin V and TUNEL labeling. Results highlight the potent antiproliferative and proapoptotic function of scoulerine in cancer cells caused by its ability to interfere with the microtubule elements of the cytoskeleton, checkpoint kinase signaling and p53 proteins. This is the first study of the mechanism of scoulerine at cellular and molecular level. Scoulerine is a potent antimitotic compound and that it merits further investigation as an anticancer drug.

  5. Cleaning and dismantling of a high activity laboratory (abstract and presentation slides)

    Energy Technology Data Exchange (ETDEWEB)

    Bredel; Thierry; Buzare, Alain

    2005-01-01

    The high activity laboratories have been built at the end of the 50ies. The particularity of this facility was that about 14 different laboratories worked in 14 different fields (biology, production of Cs and Cf sources, metallurgy, mechanical testing ...). Because of the optimization of the nuclear research, the CEA decided to close progressively this facility and to transfer the different experiments in other places. This action began in 1997 and is planed to end in 2010. 6 laboratories have been closed from 1997 to 2001 and the dismantling of the shielded cells has begun since 2002. Therefore, several laboratories have been cleaned of the materials and experiments. Nevertheless, the main particularity of this subject is that some experimental activities have been pursued during the cleaning and dismantling of other laboratories. For example, we describe the dismantling of the laboratory that performed metallurgical and mechanical characterization of irradiated materials. This laboratory occupied 20 lead cells and 2 glove boxes. The exploitation of those cells has been stopped progressively (12 at the end of 2001 and 5 at the end of 2003). The end of the last 3 cell exploitation is planed to end 2005. Since the end of 2001, 9 lead cells have been cleaned. Their dismantling is planed for next the two years. In parallel, we will clean all the other cells. During this phase we will have also to transfer all the irradiated samples (about 5000) that are still in the laboratory to the waste treatment facility of the CEA centre or to the new laboratory which has been presented during the previous hotlab meeting in Saclay. The paper gives details for background about ended operations: Organization, waste production, specific designs which improve radioprotection, waste destinations and costs, Difficulties and feedback experience of dismantling. (Author)

  6. Radiological impact of very slightly radioactive copper and aluminium recovered from dismantled nuclear facilities

    International Nuclear Information System (INIS)

    Garbay, H.; Chapuis, A.M.; Cahuzac, O.; Guetat, P.; Haristoy, D.; Renaud, P.

    1991-01-01

    This work is in keeping with a large evaluation of doses likely to be received by public and non nuclear workers when dismantling nuclear installations. A bibliographic study and inquiries are realized, in the nuclear field to evaluate quantities of very slightly radioactive materials, in the conventional copper and aluminium recovery fields: waste recovery, metal refinery and processing, occupational or domestic uses of the metals or their alloys. In fact copper and aluminium waste arising from the dismantling of nuclear installations are mainly electrical cables constituents including insulation material which is mainly polyvinyle chloride (PVC). Estimated quantities are relatively low compared to steel quantities arising from dismantling. The study is based on the hypothesis of two PWRs dismantled per year, estimated quantities are 200 tonnes of copper, 40 tonnes of aluminium and 500 tonnes of PVC. A special case is also studied, which is the dismantling of low and medium uranium enrichment plant in Pierrelatte (France); the plant pipework is mainly made of an aluminium and magnesium alloy: AG3. From these informations, one can define exposure scenarios which may occur with a non negligible probability. The doses likely to be received under the foreseen conditions are calculated. Reference doses are established from recommendations of international organisations as ICRP, IAEA, NEA. Comparing the calculated doses and the reference doses, the activity level of the initial waste can be deduced as to follow the recommendations. The mean specific activity of main beta-gamma emitters in copper, aluminium and PVC are of the same order of magnitude, 10Bq.g -1 . In the case of alpha emitters specific activity levels depend on the material and on the radionuclide, from 2 Bq.g -1 to 10 Bq.g -1 in copper, from 10 Bq.g -1 to 50 Bq.g -1 in aluminium

  7. Education and research when dismantling nuclear plants at the Technical University Dresden

    International Nuclear Information System (INIS)

    Hurtado, A.; Anthofer, A.; Cloppenborg, T.; Schreier, M.

    2013-01-01

    With the decision by the German government in 2011 to revoke the operating permission from 8 of the existing 17 German nuclear power plants, the responsibility of decommissioning and dismantling these plants has moved back into the focus of public awareness. Under the current legal conditions, the last nuclear plant will be disconnected from the grid on 31.12.2022 and this will create an enormous challenge for all the involved approving authorities, expert organisations, as well as companies involved in dismantling the plants. The development of new and efficient dismantling technologies and strategies is required to perform these highly responsible tasks. On the other hand, the nuclear competence and knowhow, as well as the promotion of young talents in the relevant scientific fields must be preserved. Technological and economic solutions are in demand for the various plants due to the different specifics of nuclear power plants. This will still require e.g. in the field of radiation protection highly qualified and well trained staff in future. The training of these skilled employees will require expanding the subject matter taught at universities, colleges and polytechnics to suit the changed parameters. The chair for hydrogen and nuclear energy technology at the TU Dresden will in future offer lectures as part of a new teaching discipline with the focus on dismantling and disposal. The course 'Dismantling nuclear power plants' took place for the first time in the summer semester 2013. It is organised as a three-day block seminar with an excursion to the company NIS Ingenieurgesellschaft mbH in Alzenau. The company NIS is a subsidiary of the Siempelkamp Nukleartechnik GmbH. This article intends to provide an overview of the contents of the courses and the impressions of the participants. In this way the TU Dresden is making a further contribution to preserving nuclear competence and inter-disciplinary dialogue. (orig.)

  8. Technical report on dismantling of incinerator building of JNC with strict environmental assessments especially for the contamination of surroundings of incinerator by Dioxin's in soil

    International Nuclear Information System (INIS)

    Aizawa, Masanori; Ohmori, Koji; Nomura, Takeshi; Numano, Tatuo; Usui, Kazuya; Irinouchi, Shigenori

    2003-03-01

    Building of incinerator for general waste located at Tokai of Japan Nuclear Cycle Development Institute (JNC in short) were dismantled form April 2002 to March 2003 under environmental control According to the regulation entitled 'Outline for the prevention of exposure of Dioxin's to operators engaged in dismantling of waste incinerator' issued on June 01, 2000 by Ministry of Health, Labor and Welfare in Japan, the regulation requests proper protection methodology to dismantling the incinerator and surroundings contaminated by Dioxin's. This report consists of Environmental assessment under Japanese law and regulations and Procedure of actual dismantling of incinerator building with law-abiding stand point. 1. Environmental assessment; Survey of several laws and regulations concerning on the Dioxin's and actual site assessment to analyze the content of Dioxin's for surroundings of incinerator building. Ground design of dismantling procedures, waste management for disposed during dismantling and scheduling for dismantling of building. 2. Dismantling procedures; Prior to dismantling operation, contamination map by Dioxin's were established then restricted areas were determined. Protection methodology to dioxin's exposure for operators were selected and started dismantling operation after getting permission from the Labor Standards Bureau of Ibaraki Prefecture. Dismantling operations were carried out with respect o above mentioned regulations to prevent the operators exposure to Dioxin's if they are exists in soil or surroundings of building. Finally, dismantling operations were completed without accidents and confirmed no-exposure of Dioxin's to operators of dismantling. Waste generated during dismantling were recycled using specialized recycling companies in Ibaraki prefecture. Dismantling operation of incinerator was first experience at Ibaraki Prefecture, so the officials of Labor Standards Bureau were carried out on-the-spot inspection and have no claim from

  9. Dismantling of nuclear facilities: the industrial know-how; Demantelement des installations nucleaires: les voies de la maitrise industrielle

    Energy Technology Data Exchange (ETDEWEB)

    Lellament, R. [Societe Francaise d' Energie Nucleaire (SFEN), Groupe de Reflexion Energie/Environnement, 75 - Paris (France)

    2004-11-01

    Numerous nuclear facilities in laboratories or research reactors have been decommissioned and dismantled over the 2 last decades throughout the world. The valuable feedback experience has allowed nuclear industry to design, upgrade and test specific techniques for dismantling. These techniques are efficient although they have been validated on a reduced number of nuclear power plants. In France only 3 power units have been dismantled: Chinon A1, A2 and Brennilis (EL4) and they are not representative of the real park of EDF'reactors. 6 PWR-type reactors have already been dismantled in the Usa. The results of a survey concerning 26 countries shows that the dismantling cost is around 320 dollars/kWe, it represents 15% of the construction cost which is far from being excessive as it is often read in the media. The dismantling costs can be broken into: - de-construction (25-55%), - wastes from dismantling (17-43%), - security and monitoring (8-13%), - site reclamation (5-13%), and - engineering and project management (5-24%). (A.C.)

  10. Cucurbitacin B inhibits human breast cancer cell proliferation through disruption of microtubule polymerization and nucleophosmin/B23 translocation

    Directory of Open Access Journals (Sweden)

    Duangmano Suwit

    2012-10-01

    Full Text Available Abstract Background Cucurbitacin B, an oxygenated tetracyclic triterpenoid compound extracted from the Thai medicinal plant Trichosanthes cucumerina L., has been reported to have several biological activities including anti-inflammatory, antimicrobial and anticancer. Cucurbitacin B is great of interest because of its biological activity. This agent inhibits growth of various types of human cancer cells lines. Methods In this study, we explored the novel molecular response of cucurbitacin B in human breast cancer cells, MCF-7 and MDA-MB-231. The growth inhibitory effect of cucurbitacin B on breast cancer cells was assessed by MTT assay. The effects of cucurbitacin B on microtubules morphological structure and tubulin polymerization were analyzed using immunofluorescence technique and tubulin polymerization assay kit, respectively. Proteomic analysis was used to identify the target-specific proteins that involved in cucurbitacin B treatment. Some of the differentially expressed genes and protein products were validated by real-time RT-PCR and western blot analysis. Cell cycle distributions and apoptosis were investigated using flow cytometry. Results Cucurbitacin B exhibited strong antiproliferative effects against breast cancer cells in a dose-dependent manner. We show that cucurbitacin B prominently alters the cytoskeletal network of breast cancer cells, inducing rapid morphologic changes and improper polymerization of the microtubule network. Moreover, the results of 2D-PAGE, real-time RT-PCR, and western blot analysis revealed that the expression of nucleophosmin/B23 and c-Myc decreased markedly after cucurbitacin B treatment. Immunofluorescence microscopy showed that cucurbitacin B induced translocation of nucleophosmin/B23 from the nucleolus to nucleoplasm. Treatment with cucurbitacin B resulted in cell cycle arrest at G2/M phase and the enhancement of apoptosis. Conclusions Our findings suggest that cucurbitacin B may inhibit the

  11. Brassinosteroids regulate pavement cell growth by mediating BIN2-induced microtubule stabilization.

    Science.gov (United States)

    Liu, Xiaolei; Yang, Qin; Wang, Yuan; Wang, Linhai; Fu, Ying; Wang, Xuelu

    2018-02-23

    Brassinosteroids (BRs), a group of plant steroid hormones, play important roles in regulating plant development. The cytoskeleton also affects key developmental processes and a deficiency in BR biosynthesis or signaling leads to abnormal phenotypes similar to those of microtubule-defective mutants. However, how BRs regulate microtubule and cell morphology remains unknown. Here, using liquid chromatography-tandem mass spectrometry, we identified tubulin proteins that interact with Arabidopsis BRASSINOSTEROID INSENSITIVE2 (BIN2), a negative regulator of BR responses in plants. In vitro and in vivo pull-down assays confirmed that BIN2 interacts with tubulin proteins. High-speed co-sedimentation assays demonstrated that BIN2 also binds microtubules. The Arabidopsis genome also encodes two BIN2 homologs, BIN2-LIKE 1 (BIL1) and BIL2, which function redundantly with BIN2. In the bin2-3 bil1 bil2 triple mutant, cortical microtubules were more sensitive to treatment with the microtubule-disrupting drug oryzalin than in wild-type, whereas in the BIN2 gain-of-function mutant bin2-1, cortical microtubules were insensitive to oryzalin treatment. These results provide important insight into how BR regulates plant pavement cell and leaf growth by mediating the stabilization of microtubules by BIN2.

  12. Clostridium difficile toxin CDT induces formation of microtubule-based protrusions and increases adherence of bacteria.

    Directory of Open Access Journals (Sweden)

    Carsten Schwan

    2009-10-01

    Full Text Available Clostridium difficile causes antibiotic-associated diarrhea and pseudomembranous colitis by production of the Rho GTPase-glucosylating toxins A and B. Recently emerging hypervirulent Clostridium difficile strains additionally produce the binary ADP-ribosyltransferase toxin CDT (Clostridium difficile transferase, which ADP-ribosylates actin and inhibits actin polymerization. Thus far, the role of CDT as a virulence factor is not understood. Here we report by using time-lapse- and immunofluorescence microscopy that CDT and other binary actin-ADP-ribosylating toxins, including Clostridium botulinum C2 toxin and Clostridium perfringens iota toxin, induce redistribution of microtubules and formation of long (up to >150 microm microtubule-based protrusions at the surface of intestinal epithelial cells. The toxins increase the length of decoration of microtubule plus-ends by EB1/3, CLIP-170 and CLIP-115 proteins and cause redistribution of the capture proteins CLASP2 and ACF7 from microtubules at the cell cortex into the cell interior. The CDT-induced microtubule protrusions form a dense meshwork at the cell surface, which wrap and embed bacterial cells, thereby largely increasing the adherence of Clostridia. The study describes a novel type of microtubule structure caused by less efficient microtubule capture and offers a new perspective for the pathogenetic role of CDT and other binary actin-ADP-ribosylating toxins in host-pathogen interactions.

  13. Structural differences between yeast and mammalian microtubules revealed by cryo-EM

    Energy Technology Data Exchange (ETDEWEB)

    Howes, Stuart C. [Univ. of California, Berkeley, CA (United States). Biophysics Graduate Group; Geyer, Elisabeth A. [Univ. of Texas Southwestern Medical Center, Dallas, TX (United States). Dept. of Biophysics; Univ. of Texas Southwestern Medical Center, Dallas, TX (United States). Dept. of Biochemistry; LaFrance, Benjamin [Univ. of California, Berkeley, CA (United States). Molecular and Cell Biology Graduate Program; Zhang, Rui [Univ. of California, Berkeley, CA (United States). Howard Hughes Medical Inst.; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Molecular Biophysics and Integrated Bioimaging Division; Kellogg, Elizabeth H. [Univ. of California, Berkeley, CA (United States). Howard Hughes Medical Inst.; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Molecular Biophysics and Integrated Bioimaging Division; Westermann, Stefan [Univ. of Duisburg-Essen, Essen (Germany). Dept. of Molecular Genetics, Center for Medical Biotechnology; Rice, Luke M. [Univ. of Texas Southwestern Medical Center, Dallas, TX (United States). Dept. of Biophysics; Univ. of Texas Southwestern Medical Center, Dallas, TX (United States). Dept. of Biochemistry; Nogales, Eva [Univ. of California, Berkeley, CA (United States). Howard Hughes Medical Inst.; Univ. of California, Berkeley, CA (United States). Dept. of Molecular Biology and California Inst. for Quantitative Biosciences; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Molecular Biophysics and Integrated Bioimaging Division

    2017-06-26

    Microtubules are polymers of αβ-tubulin heterodimers essential for all eukaryotes. Despite sequence conservation, there are significant structural differences between microtubules assembled in vitro from mammalian or budding yeast tubulin. Yeast MTs were not observed to undergo compaction at the interdimer interface as seen for mammalian microtubules upon GTP hydrolysis. Lack of compaction might reflect slower GTP hydrolysis or a different degree of allosteric coupling in the lattice. The microtubule plus end–tracking protein Bim1 binds yeast microtubules both between αβ-tubulin heterodimers, as seen for other organisms, and within tubulin dimers, but binds mammalian tubulin only at interdimer contacts. At the concentrations used in cryo-electron microscopy, Bim1 causes the compaction of yeast microtubules and induces their rapid disassembly. In conclusion, our studies demonstrate structural differences between yeast and mammalian microtubules that likely underlie their differing polymerization dynamics. These differences may reflect adaptations to the demands of different cell size or range of physiological growth temperatures.

  14. Buckling analysis of orthotropic protein microtubules under axial and radial compression based on couple stress theory.

    Science.gov (United States)

    Beni, Yaghoub Tadi; Zeverdejani, M Karimi; Mehralian, Fahimeh

    2017-10-01

    Protein microtubules (MTs) are one of the important intercellular components and have a vital role in the stability and strength of the cells. Due to applied external loads, protein microtubules may be involved buckling phenomenon. Due to impact of protein microtubules in cell reactions, it is important to determine their critical buckling load. Considering nature of protein microtubules, various parameters are effective on microtubules buckling. The small size of microtubules and also lack of uniformity of MTs properties in different directions caused the necessity of accuracy in the analysis of these bio-structure. In fact, microtubules must be considered as a size dependent cylinder, which behave as an orthotropic material. Hence, in the present work using first-order shear deformation model (FSDT), the buckling equations of anisotropic MTs are derived based on new modified couple stress theory (NMCST). After solving the stability equations, the influences of various parameters are measured on the MTs critical buckling load. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Model for the orientational ordering of the plant microtubule cortical array

    Science.gov (United States)

    Hawkins, Rhoda J.; Tindemans, Simon H.; Mulder, Bela M.

    2010-07-01

    The plant microtubule cortical array is a striking feature of all growing plant cells. It consists of a more or less homogeneously distributed array of highly aligned microtubules connected to the inner side of the plasma membrane and oriented transversely to the cell growth axis. Here, we formulate a continuum model to describe the origin of orientational order in such confined arrays of dynamical microtubules. The model is based on recent experimental observations that show that a growing cortical microtubule can interact through angle dependent collisions with pre-existing microtubules that can lead either to co-alignment of the growth, retraction through catastrophe induction or crossing over the encountered microtubule. We identify a single control parameter, which is fully determined by the nucleation rate and intrinsic dynamics of individual microtubules. We solve the model analytically in the stationary isotropic phase, discuss the limits of stability of this isotropic phase, and explicitly solve for the ordered stationary states in a simplified version of the model.

  16. Measurement of in vitro microtubule polymerization by turbidity and fluorescence.

    Science.gov (United States)

    Mirigian, Matthew; Mukherjee, Kamalika; Bane, Susan L; Sackett, Dan L

    2013-01-01

    Tubulin polymerization may be conveniently monitored by the increase in turbidity (optical density, or OD) or by the increase in fluorescence intensity of diamidino-phenylindole. The resulting data can be a quantitative measure of microtubule (MT) assembly, but some care is needed in interpretation, especially of OD data. Buffer formulations used for the assembly reaction significantly influence the polymerization, both by altering the critical concentration for polymerization and by altering the exact polymer produced-for example, by increasing the production of sheet polymers in addition to MT. Both the turbidity and the fluorescence methods are useful for demonstrating the effect of MT-stabilizing or -destabilizing additives. 2013 Published by Elsevier Inc.

  17. HSPB1 facilitates the formation of non-centrosomal microtubules.

    Directory of Open Access Journals (Sweden)

    Leonardo Almeida-Souza

    Full Text Available The remodeling capacity of microtubules (MT is essential for their proper function. In mammals, MTs are predominantly formed at the centrosome, but can also originate from non-centrosomal sites, a process that is still poorly understood. We here show that the small heat shock protein HSPB1 plays a role in the control of non-centrosomal MT formation. The HSPB1 expression level regulates the balance between centrosomal and non-centrosomal MTs. The HSPB1 protein can be detected specifically at sites of de novo forming non-centrosomal MTs, while it is absent from the centrosomes. In addition, we show that HSPB1 binds preferentially to the lattice of newly formed MTs in vitro, suggesting that its function occurs by stabilizing MT seeds. Our findings open new avenues for the understanding of the role of HSPB1 in the development, maintenance and protection of cells with specialized non-centrosomal MT arrays.

  18. Near-atomic model of microtubule-tau interactions.

    Science.gov (United States)

    Kellogg, Elizabeth H; Hejab, Nisreen M A; Poepsel, Simon; Downing, Kenneth H; DiMaio, Frank; Nogales, Eva

    2018-06-15

    Tau is a developmentally regulated axonal protein that stabilizes and bundles microtubules (MTs). Its hyperphosphorylation is thought to cause detachment from MTs and subsequent aggregation into fibrils implicated in Alzheimer's disease. It is unclear which tau residues are crucial for tau-MT interactions, where tau binds on MTs, and how it stabilizes them. We used cryo-electron microscopy to visualize different tau constructs on MTs and computational approaches to generate atomic models of tau-tubulin interactions. The conserved tubulin-binding repeats within tau adopt similar extended structures along the crest of the protofilament, stabilizing the interface between tubulin dimers. Our structures explain the effect of phosphorylation on MT affinity and lead to a model of tau repeats binding in tandem along protofilaments, tethering together tubulin dimers and stabilizing polymerization interfaces. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  19. STIM1-Directed Reorganization of Microtubules in Activated Mast Cells

    Czech Academy of Sciences Publication Activity Database

    Hájková, Zuzana; Bugajev, Viktor; Dráberová, Eduarda; Vinopal, Stanislav; Dráberová, Lubica; Janáček, Jiří; Dráber, Petr; Dráber, Pavel

    2011-01-01

    Roč. 186, č. 2 (2011), s. 913-923 ISSN 0022-1767 R&D Projects: GA ČR(CZ) GD204/09/H084; GA ČR GA204/09/1777; GA ČR GA301/09/1826; GA ČR GAP302/10/1759; GA MŠk LC545; GA MŠk(CZ) LC06063; GA AV ČR KAN200520701 Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50110509 Keywords : STIM1 * bone marrow-derived mast cells * microtubules Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.788, year: 2011

  20. Complementary activities of TPX2 and chTOG constitute an efficient importin-regulated microtubule nucleation module.

    Science.gov (United States)

    Roostalu, Johanna; Cade, Nicholas I; Surrey, Thomas

    2015-11-01

    Spindle assembly and function require precise control of microtubule nucleation and dynamics. The chromatin-driven spindle assembly pathway exerts such control locally in the vicinity of chromosomes. One of the key targets of this pathway is TPX2. The molecular mechanism of how TPX2 stimulates microtubule nucleation is not understood. Using microscopy-based dynamic in vitro reconstitution assays with purified proteins, we find that human TPX2 directly stabilizes growing microtubule ends and stimulates microtubule nucleation by stabilizing early microtubule nucleation intermediates. Human microtubule polymerase chTOG (XMAP215/Msps/Stu2p/Dis1/Alp14 homologue) only weakly promotes nucleation, but acts synergistically with TPX2. Hence, a combination of distinct and complementary activities is sufficient for efficient microtubule formation in vitro. Importins control the efficiency of the microtubule nucleation by selectively blocking the interaction of TPX2 with microtubule nucleation intermediates. This in vitro reconstitution reveals the molecular mechanism of regulated microtubule formation by a minimal nucleation module essential for chromatin-dependent microtubule nucleation in cells.

  1. A Mechanism for Cytoplasmic Streaming: Kinesin-Driven Alignment of Microtubules and Fast Fluid Flows.

    Science.gov (United States)

    Monteith, Corey E; Brunner, Matthew E; Djagaeva, Inna; Bielecki, Anthony M; Deutsch, Joshua M; Saxton, William M

    2016-05-10

    The transport of cytoplasmic components can be profoundly affected by hydrodynamics. Cytoplasmic streaming in Drosophila oocytes offers a striking example. Forces on fluid from kinesin-1 are initially directed by a disordered meshwork of microtubules, generating minor slow cytoplasmic flows. Subsequently, to mix incoming nurse cell cytoplasm with ooplasm, a subcortical layer of microtubules forms parallel arrays that support long-range, fast flows. To analyze the streaming mechanism, we combined observations of microtubule and organelle motions with detailed mathematical modeling. In the fast state, microtubules tethered to the cortex form a thin subcortical layer and undergo correlated sinusoidal bending. Organelles moving in flows along the arrays show velocities that are slow near the cortex and fast on the inward side of the subcortical microtubule layer. Starting with fundamental physical principles suggested by qualitative hypotheses, and with published values for microtubule stiffness, kinesin velocity, and cytoplasmic viscosity, we developed a quantitative coupled hydrodynamic model for streaming. The fully detailed mathematical model and its simulations identify key variables that can shift the system between disordered (slow) and ordered (fast) states. Measurements of array curvature, wave period, and the effects of diminished kinesin velocity on flow rates, as well as prior observations on f-actin perturbation, support the model. This establishes a concrete mechanistic framework for the ooplasmic streaming process. The self-organizing fast phase is a result of viscous drag on kinesin-driven cargoes that mediates equal and opposite forces on cytoplasmic fluid and on microtubules whose minus ends are tethered to the cortex. Fluid moves toward plus ends and microtubules are forced backward toward their minus ends, resulting in buckling. Under certain conditions, the buckling microtubules self-organize into parallel bending arrays, guiding varying directions

  2. An Evaluation of Dismantling Scenarios Using a Computer Simulation Technology for KRR-1 and 2

    International Nuclear Information System (INIS)

    Kim, S.K.; Park, H.S.; Lee, K.W.; Oh, W.Z.; Park, J.H.

    2006-01-01

    A graphic simulation has been used to design and verify new equipment and has also been expanded to virtual prototyping technology [1∼5]. In the nuclear decommissioning field, this technology has been utilized to validate the design of dismantling processes and to check the interferences and collisions in dismantling scenarios. However, a graphic simulation only provides us with visible result it just provides us with illustrative information of the decommissioning process. A scenario evaluation program has been developed using the computer simulation technology to create an efficient decommissioning plan. In the D and D planning stage, it is important that the scenarios are evaluated from a engineering point of view because the decommissioning work has to be executed economically and safely following the best scenarios. Therefore, we need several modules to evaluate scenarios. We composed the systems like this: 1. Decommissioning DB module for managing the decommissioning activity information (nuclear facility data, worker's data, radioactive inventory date, etc.). Dismantling process evaluation module 3. Visualization module for a radioactive inventory and a dismantling process using 3D CAD and virtual reality technology. 4. Analysis module for the evaluation results of a dismantling process. The evaluation module's capabilities produce a dismantling schedule, quantify radioactive waste, visualize a radioactive inventory, estimate a decommissioning cost, estimate a worker's exposure, and check for interference/collisions. After using the simulation results, the expert ranking system to evaluate scenarios for economics and worker's safety are implemented. The expert ranking system is a powerful and flexible decision making process to help set priorities and make the best decisions when both the qualitative and quantitative aspects of a decision need to be considered. By reducing complex decisions to a series of one-on-one comparisons, then synthesizing the

  3. Tracking of plus-ends reveals microtubule functional diversity in different cell types

    Science.gov (United States)

    Shaebani, M. Reza; Pasula, Aravind; Ott, Albrecht; Santen, Ludger

    2016-07-01

    Many cellular processes are tightly connected to the dynamics of microtubules (MTs). While in neuronal axons MTs mainly regulate intracellular trafficking, they participate in cytoskeleton reorganization in many other eukaryotic cells, enabling the cell to efficiently adapt to changes in the environment. We show that the functional differences of MTs in different cell types and regions is reflected in the dynamic properties of MT tips. Using plus-end tracking proteins EB1 to monitor growing MT plus-ends, we show that MT dynamics and life cycle in axons of human neurons significantly differ from that of fibroblast cells. The density of plus-ends, as well as the rescue and catastrophe frequencies increase while the growth rate decreases toward the fibroblast cell margin. This results in a rather stable filamentous network structure and maintains the connection between nucleus and membrane. In contrast, plus-ends are uniformly distributed along the axons and exhibit diverse polymerization run times and spatially homogeneous rescue and catastrophe frequencies, leading to MT segments of various lengths. The probability distributions of the excursion length of polymerization and the MT length both follow nearly exponential tails, in agreement with the analytical predictions of a two-state model of MT dynamics.

  4. Vibration, buckling and smart control of microtubules using piezoelectric nanoshells under electric voltage in thermal environment

    Energy Technology Data Exchange (ETDEWEB)

    Farajpour, A., E-mail: ariobarzan.oderj@gmail.com; Rastgoo, A.; Mohammadi, M.

    2017-03-15

    Piezoelectric nanomaterials such as zinc oxide (ZnO) are of low toxicity and have many biomedical applications including optical imaging, drug delivery, biosensing and harvesting biomechanical energy using hybrid nanogenerators. In this paper, the vibration, buckling and smart control of microtubules (MTs) embedded in an elastic medium in thermal environment using a piezoelectric nanoshell (PNS) are investigated. The MT and PNS are considered to be coupled by a filament network. The PNS is subjected to thermal loads and an external electric voltage which operates to control the mechanical behavior of the MT. Using the nonlocal continuum mechanics, the governing differential equations are derived. An exact solution is presented for simply supported boundary conditions. The differential quadrature method is also used to solve the governing equations for other boundary conditions. A detailed parametric study is conducted to investigate the effects of the elastic constants of surrounding medium and internal filament matrix, scale coefficient, electric voltage, the radius-to-thickness ratio of PNSs and temperature change on the smart control of MTs. It is found that the applied electric voltage can be used as an effective controlling parameter for the vibration and buckling of MTs.

  5. Bacillus anthracis TIR Domain-Containing Protein Localises to Cellular Microtubule Structures and Induces Autophagy.

    Science.gov (United States)

    Carlsson, Emil; Thwaite, Joanne E; Jenner, Dominic C; Spear, Abigail M; Flick-Smith, Helen; Atkins, Helen S; Byrne, Bernadette; Ding, Jeak Ling

    2016-01-01

    Toll-like receptors (TLRs) recognise invading pathogens and mediate downstream immune signalling via Toll/IL-1 receptor (TIR) domains. TIR domain proteins (Tdps) have been identified in multiple pathogenic bacteria and have recently been implicated as negative regulators of host innate immune activation. A Tdp has been identified in Bacillus anthracis, the causative agent of anthrax. Here we present the first study of this protein, designated BaTdp. Recombinantly expressed and purified BaTdp TIR domain interacted with several human TIR domains, including that of the key TLR adaptor MyD88, although BaTdp expression in cultured HEK293 cells had no effect on TLR4- or TLR2- mediated immune activation. During expression in mammalian cells, BaTdp localised to microtubular networks and caused an increase in lipidated cytosolic microtubule-associated protein 1A/1B-light chain 3 (LC3), indicative of autophagosome formation. In vivo intra-nasal infection experiments in mice showed that a BaTdp knockout strain colonised host tissue faster with higher bacterial load within 4 days post-infection compared to the wild type B. anthracis. Taken together, these findings indicate that BaTdp does not play an immune suppressive role, but rather, its absence increases virulence. BaTdp present in wild type B. anthracis plausibly interact with the infected host cell, which undergoes autophagy in self-defence.

  6. Cortical microtubule nucleation can organise the cytoskeleton of Drosophila oocytes to define the anteroposterior axis

    Science.gov (United States)

    Khuc Trong, Philipp; Doerflinger, Hélène; Dunkel, Jörn; St Johnston, Daniel; Goldstein, Raymond E

    2015-01-01

    Many cells contain non-centrosomal arrays of microtubules (MTs), but the assembly, organisation and function of these arrays are poorly understood. We present the first theoretical model for the non-centrosomal MT cytoskeleton in Drosophila oocytes, in which bicoid and oskar mRNAs become localised to establish the anterior-posterior body axis. Constrained by experimental measurements, the model shows that a simple gradient of cortical MT nucleation is sufficient to reproduce the observed MT distribution, cytoplasmic flow patterns and localisation of oskar and naive bicoid mRNAs. Our simulations exclude a major role for cytoplasmic flows in localisation and reveal an organisation of the MT cytoskeleton that is more ordered than previously thought. Furthermore, modulating cortical MT nucleation induces a bifurcation in cytoskeletal organisation that accounts for the phenotypes of polarity mutants. Thus, our three-dimensional model explains many features of the MT network and highlights the importance of differential cortical MT nucleation for axis formation. DOI: http://dx.doi.org/10.7554/eLife.06088.001 PMID:26406117

  7. Non-critical string theory formulation of microtubule dynamics and quantum aspects of brain function

    CERN Document Server

    Mavromatos, Nikolaos E

    1995-01-01

    Microtubule (MT) networks, subneural paracrystalline cytosceletal structures, seem to play a fundamental role in the neurons. We cast here the complicated MT dynamics in the form of a 1+1-dimensional non-critical string theory, thus enabling us to provide a consistent quantum treatment of MTs, including enviromental {\\em friction} effects. We suggest, thus, that the MTs are the microsites, in the brain, for the emergence of stable, macroscopic quantum coherent states, identifiable with the {\\em preconscious states}. Quantum space-time effects, as described by non-critical string theory, trigger then an {\\em organized collapse} of the coherent states down to a specific or {\\em conscious state}. The whole process we estimate to take {\\cal O}(1\\,{\\rm sec}), in excellent agreement with a plethora of experimental/observational findings. The {\\em microscopic arrow of time}, endemic in non-critical string theory, and apparent here in the self-collapse process, provides a satisfactory and simple resolution to the age...

  8. Networking

    OpenAIRE

    Rauno Lindholm, Daniel; Boisen Devantier, Lykke; Nyborg, Karoline Lykke; Høgsbro, Andreas; Fries, de; Skovlund, Louise

    2016-01-01

    The purpose of this project was to examine what influencing factor that has had an impact on the presumed increasement of the use of networking among academics on the labour market and how it is expressed. On the basis of the influence from globalization on the labour market it can be concluded that the globalization has transformed the labour market into a market based on the organization of networks. In this new organization there is a greater emphasis on employees having social qualificati...

  9. The preliminary 3D dynamic simulation on the RSR dismantling process of the KRR-1 and 2

    International Nuclear Information System (INIS)

    Kim, Hee-Reyoung; Kim, Sung-Kyun; Seo, Bum-Kyoung; Lee, Kune-Woo; Park, Jin-Ho

    2003-01-01

    A three-dimensional graphic simulation has been carried out for the dismantling process of the Rotary Specimen Rack(RSR) in the Korea Research Reactor-1 and 2 (KRR-1 and 2). First of all, the general steps of the graphic simulation were established and reviewed for the dismantling process of the object. Four dismantling processes, which are the removal of RSR, reactor core region, beam tube, and thermal column and activated concrete, were selected for the graphic simulation on the virtual space by the consideration of the activation, worker training, work difficulty and so on. In the present study, the dismantling procedure of the RSR was divided into several steps and its visual simulation was performed by the 3D graphic software. Finally, the simulation result was converted to moving file with extension of AVI so that easy approach can be made on window OS system

  10. Radioactive waste management, decommissioning, spent fuel storage. V. 1. Waste management principles, decommissioning, dismantling, operations in hot environment

    International Nuclear Information System (INIS)

    1985-01-01

    This book deals mainly with decommissioning problems concerning more particularly dismantling and decontamination techniques, and radioactive waste processing. Radioactive waste management in France and the French regulation are tackled. Equipments developed for works in hostile environment are also presented [fr

  11. Dismantling and removal of the Niederaichbach nuclear power plant (KKN) to the 'Green Field'. Final report

    International Nuclear Information System (INIS)

    Valencia, L.; Prechtl, E.

    1998-04-01

    The major objective of the present project consisted in the complete dismantling and removal of the Niederaichbach nuclear power plant (KKN), ranging from the state of safe enclosure to re-establishing the original state of vegetation of the site (so-called 'green field'). By reaching this objective, principle feasibility of the complete removal of a power reactor was demonstrated. In addition, considerable experience has been gained with regard to the execution of all phases of such a complex project and project optimization. The following phases of the project can be distinguished: - Licensing procedure - dismantling of the inactive, contaminated and activated plant sections - disassembly of the activated building structures and decontamination of the buildings - demolition (conventional) of the buildings and recultivation of the site. Moreover, the project included the work performed under the direct supervision of the licensing authority, comprehensive radiation protection activities, the solution of waste management problems and the respective public relations work. (orig./MM) [de

  12. EDV supported dynamic fire protection concept adaptation during dismantling of nuclear facilities

    International Nuclear Information System (INIS)

    Mummert, Maxi; Traichel, Anke; Dilger, Matthias

    2013-01-01

    Fire protection concepts are supposed to be a decision guide for the definition of measures and priorities in fire fighting and fire prevention. In case of reactor dismantling a fire protection concept for the actual status is required. Following the fuel removal from the reactor the protection goals are reduced to the safe confinement of radioactive materials and the restriction of radiation exposure. A dynamic fire protection concept was developed to allow the compliance with the required protection measures with respect to the protection targets. The implementation of the dynamic fire protection concept simplifies the planning of the dismantling steps and to adjust the fire protection measured in the frame of changes in the plant.

  13. NEA's analysis of the needs in innovation and research in the domain of dismantling

    International Nuclear Information System (INIS)

    Laurent, G.

    2014-01-01

    Today's approach of the dismantling of nuclear facilities is labour intensive and consequently very expensive. NEA's study suggests that research works should be done to find more efficient technologies for decontamination and dismantling. 5 lines of research have been identified by NEA. First, new technologies must be found to get a more accurate spatial distribution of contaminants. Secondly, the different cutting methods must be assessed in terms of efficiency, dosimetry and secondary waste generation. Thirdly, a better understanding of the chemical and physical processes that may be used for the decontamination of metals, concretes, underground water and soil. Fourthly, the management of radioactive waste implies to know the interaction between wastes and packages over a very long period. Fifthly, an accurate characterization of a complex site housing various contaminating sources and different hydro-geological conditions implies the development of 3-dimensional radiation transport codes and the use of innovative means like satellite monitoring. (A.C.)

  14. Development and evaluation of a dismantling planning support system based on augmented reality technology

    International Nuclear Information System (INIS)

    Ishii, Hirotake; Oshita, Satoshi; Yan Weida; Shimoda, Hiroshi; Izumi, Masanori

    2011-01-01

    For this study, a Dismantling Planning Support System (DPSS) based on Augmented Reality technology was developed. Its effectiveness and applicability to a real working field were evaluated using a subjective experiment. The DPSS operators can simulate how to locate scaffolding and temporary enclosures (greenhouses) in a real dismantling field in order to decide their layout and to predict the amounts of necessary parts. An interview and questionnaire survey were conducted with Fugen Decommissioning Engineering Center (DEC) staff and a human interface expert, who used DPSS along with a scenario in which scaffolding and greenhouses were located in a turbine cooling water room of Fugen DEC. The experimental results show that the operation for locating the virtual scaffolding and greenhouses using marker boards is intuitive and comprehensive. However, additional research needs to be undertaken in order to improve the DPSS, particularly with respect to its graphical user interface. (author)

  15. The Molten Salt Reactor option for beneficial use of fissile material from dismantled weapons

    International Nuclear Information System (INIS)

    Gat, U.; Engel, J.R.; Dodds, H.L.

    1991-01-01

    The Molten Salt Reactor (MSR) option for burning fissile fuel from dismantled weapons is examined. It is concluded that MSRs are very suitable for beneficial utilization of the dismantled fuel. The MSRs can utilize any fissile fuel in continuous operation with no special modifications, as demonstrated in the Molten Salt Reactor Experiment. Thus MSRs are flexible while maintaining their economy. MSRs further require a minimum of special fuel preparation and can tolerate denaturing and dilution of the fuel. Fuel shipments can be arbitrarily small, all of which supports nonproliferation and averts diversion. MSRs have inherent safety features which make them acceptable and attractive. They can burn a fuel type completely and convert it to other fuels. MSRs also have the potential for burning the actinides and delivering the waste in an optimal form, thus contributing to the solution of one of the major remaining problems for deployment of nuclear power. 19 refs

  16. The role of congress in future disposal of fissile materials from dismantled nuclear weapons

    International Nuclear Information System (INIS)

    Donnelly, W.H.; Davis, Z.S.

    1991-01-01

    Assuming the Soviet Union remains intact as a major power and the superpowers do not retrogress to a new Cold War era, it is likely that the United States and the Soviet Union will eventually agree to deep cuts in their nuclear arsenals. Future arms control agreements may be coupled with companion agreements to stop production of fissile materials for nuclear weapons, to dismantle the warheads of the nuclear weapons, and to dispose of their fissile materials to prevent reuse in new warheads. Such agreements would be negotiated by the U.S. executive branch but probably would require ratification, funding, and enabling legislation from the U.S. Congress if they are to succeed. There follows a brief review of the ideas for disposal of fissile materials from dismantled nuclear warheads and the potential role and influence of the Congress in the negotiation, ratification, and implementation of U.S.-Soviet agreements for such disposal

  17. Regulatory supervision of the radiation protection and release during the dismantling of the German NPP Wuergassen

    International Nuclear Information System (INIS)

    Boerchers, F.; Hillberg, M.

    2003-01-01

    The NPP Wuergassen (KWW) is a commercial, single unit boiling water reactor with a capacity of 670 MW el . It was commissioned by PreussenElektra and constructed by AEG/KWU between 1968 and 1971. This NPP was finally shut down in 1994. The decommissioning, started in April 1997, is still under progress. Up to now, approx. 9,500 Mg of various materials (e.g. metal scrap, cable, concrete) have been deconstructed and released from the site. In this paper we describe the contribution from the authority and the independent expert during the radiological characterisation, the dismantling work, and the material flow up to the release. Special focus will be on the necessary control steps and the documentation regarding the dismantling work and the procedure of release. There is always a close fit between the radiation protection and the release of material on the basis of the radiological characterisation. (authors)

  18. Radiation protection during backfitting or dismantling work in the controlled area of nuclear facilities

    International Nuclear Information System (INIS)

    Baumann, J.; Kausch, S.; Palmowski, J.

    1980-01-01

    Backfitting measures or dismantling activities within the controlled area put special requirements on radiological protection. This is to be shown by the example of the following cases. Sanitation of the general decontamination services of the Karlsruhe Nuclear Research Center; waste water, equipment decontamination, incineration and packaging facility; dismantling and disposal of high-radiation components including decontamination of buildings of the Eurochemic reprocessing plant at Mol; reconstruction of the HDR plant for safety experiments together with waste management for components and systems, as e.g. pressure vessel internals, pipes etc.; exchange of the steam dryer and the water separator including planning of the conditioning process in the Wuergassen nuclear power plant. This lecture deals with the engineering and organizational problems, especially accounting for radiological protection and enters into planning of measures for radiological protection, their organization and execution, problems of direct and remote-controlled work also being discussed. The question of personnel qualification is also commented on. (orig.) [de

  19. Dismantling of Radium-226 Coal Level Gauges: Encountered Problems and How to Solve

    International Nuclear Information System (INIS)

    Punnachaiya, M.; Nuanjan, P.; Moombansao, K.; Sawangsri, T.; Pruantonsai, P.; Srichom, K.

    2006-01-01

    This paper describes the techniques for dismantling of disused-sealed Radium-226 (Ra-226) coal level gauges which the source specifications and documents were not available, including problems occurred during dismantling stage and the decision making in solving all those obstacles. The 2 mCi (20 pieces), 6 mCi (20 pieces) and 6.6 mCi (30 pieces) of Ra-226 hemi-spherically-shaped with lead-filled coal level gauges were used in industrial applications for electric power generation. All sources needed to be dismantled for further conditioning as requested by the International Atomic Energy Agency (IAEA). One of the 2 mCi Ra-226 source was dismantled under the supervision of IAEA expert. Before conditioning period, each of the 6 mCi and 6.6 mCi sources were dismantled and inspected. It was found that coal level gauges had two different source types: the sealed cylindrical source (diameter 2 cm x 2 cm length) locked with spring in lead housing for 2 mCi and 6.6 mCi; while the 6 mCi was an embedded capsule inside source holder stud assembly in lead-filled housing. Dismantling Ra-226 coal level gauges comprised of 6 operational steps: confirmation of the surface dose rate on each source activity, calculation of working time within the effective occupational dose limit, cutting the weld of lead container by electrical blade, confirmation of the Ra-226 embedded capsule size using radiation scanning technique and gamma radiography, automatic sawing of the source holder stud assembly, and transferring the source to store in lead safe box. The embedded length of 6 mCi Ra-226 capsule in its diameter 2 cm x 14.7 cm length stud assembly was identified, the results from scanning technique and radiographic film revealed the embedded source length of about 2 cm, therefore all the 6 mCi sources were safely cut at 3 cm using the automatic saw. Another occurring problem was one of the 6.6 mCi spring type source stuck inside its housing because the spring was deformed and there was

  20. The management of radioactive wastes and the dismantling of nuclear installations in Spain

    International Nuclear Information System (INIS)

    Bouchet, Bertrand

    2014-08-01

    This report first presents the Spanish institutional framework, briefly presents the multi-year national plan of management of radioactive wastes, and indicates the origin and volume of radioactive wastes produced in Spain. It addresses the management of low and medium level wastes, the case of spent fuel and high level wastes (storage in pool and installations of temporary warehousing, project of a centralized temporary storage, the question of definitive management), and proposes an overview of R and D activities in the different domains of waste management in Spain: waste technology, technologies and processes of treatment, packaging and dismantling, materials and containment systems, behaviour and safety assessment, radiological protection and associated modelling, infrastructure and cooperation. The two last parts briefly address the funding of waste management and the dismantling of nuclear installations