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Sample records for synaptonemal complex disassembly

  1. Meiosis in mice without a synaptonemal complex.

    Directory of Open Access Journals (Sweden)

    Anna Kouznetsova

    Full Text Available The synaptonemal complex (SC promotes fusion of the homologous chromosomes (synapsis and crossover recombination events during meiosis. The SC displays an extensive structural conservation between species; however, a few organisms lack SC and execute meiotic process in a SC-independent manner. To clarify the SC function in mammals, we have generated a mutant mouse strain (Sycp1(-/-Sycp3(-/-, here called SC-null in which all known SC proteins have been displaced from meiotic chromosomes. While transmission electron microscopy failed to identify any remnants of the SC in SC-null spermatocytes, neither formation of the cohesion axes nor attachment of the chromosomes to the nuclear membrane was perturbed. Furthermore, the meiotic chromosomes in SC-null meiocytes achieved pre-synaptic pairing, underwent early homologous recombination events and sustained a residual crossover formation. In contrast, in SC-null meiocytes synapsis and MLH1-MLH3-dependent crossovers maturation were abolished, whereas the structural integrity of chromosomes was drastically impaired. The variable consequences that SC inactivation has on the meiotic process in different organisms, together with the absence of SC in some unrelated species, imply that the SC could have originated independently in different taxonomic groups.

  2. Structure and composition of synaptonemal complexes, isolated from rat spermatocytes

    NARCIS (Netherlands)

    Heyting, C.; Dietrich, A. J.; Redeker, E. J.; Vink, A. C.

    1985-01-01

    Synaptonemal complexes (SCs) (structures involved in chromosome pairing during meiosis) were isolated and purified from rat spermatocytes for the purpose of biochemical and morphological analysis. Spermatocytes were lysed in a medium, containing Triton X-100, EDTA and DTT; the resulting swollen

  3. An Atomic Force Microscopical Study of the Synaptonemal Complex

    NARCIS (Netherlands)

    Putman, C.A.J.; Putman, C.A.J.; Dietrich, A.J.J.; de Grooth, B.G.; van Marle, J.; Heyting, C.; van Hulst, N.F.; Greve, Jan

    1993-01-01

    The chromosomal structure which is specific for meiosis, the synaptonemal complex (SC), plays a major role in chromosome pairing and the recombination of genetic material. The SC was studied using atomic force microscopy (AFM). The results of this study confirm the results of light and electron

  4. Synaptonemal complexes at premeiotic interphase in the mouse spermatocyte

    International Nuclear Information System (INIS)

    Grell, R.F.; Oakberg, E.F.; Generoso, E.E.

    1980-01-01

    Male mice were injected intraperitoneally with 125 μCi(1 Ci = 3.7 x 10 10 becquerels) of [ 3 H]thymidine at 1-h intervals and killed 1 h after the second injection. Testes were prepared for bright-field and electron microscopic autoradiography. Primary spermatocytes, identified by light microscopy to be at the premeiotic interphase stage, were found to be heavily labeled. Electron microscopic examination disclosed the coincidental occurrence of synaptonemal complexes and label within the nuclei of premeiotic interphase spermatocytes, indicating synapses of homologues had begun during the S phase. The significance of this finding for the traditional view of meiosis is discussed

  5. Interference-mediated synaptonemal complex formation with embedded crossover designation

    Science.gov (United States)

    Zhang, Liangran; Espagne, Eric; de Muyt, Arnaud; Zickler, Denise; Kleckner, Nancy E.

    2014-01-01

    Biological systems exhibit complex patterns at length scales ranging from the molecular to the organismic. Along chromosomes, events often occur stochastically at different positions in different nuclei but nonetheless tend to be relatively evenly spaced. Examples include replication origin firings, formation of chromatin loops along chromosome axes and, during meiosis, localization of crossover recombination sites (“crossover interference”). We present evidence in the fungus Sordaria macrospora that crossover interference is part of a broader pattern that includes synaptonemal complex (SC) nucleation. This pattern comprises relatively evenly spaced SC nucleation sites, among which a subset are crossover sites that show a classical interference distribution. This pattern ensures that SC forms regularly along the entire length of the chromosome as required for the maintenance of homolog pairing while concomitantly having crossover interactions locally embedded within the SC structure as required for both DNA recombination and structural events of chiasma formation. This pattern can be explained by a threshold-based designation and spreading interference process. This model can be generalized to give diverse types of related and/or partially overlapping patterns, in two or more dimensions, for any type of object. PMID:25380597

  6. Solving a meiotic LEGO puzzle: transverse filaments and the assembly of the synaptonemal complex in Caenorhabditis elegans.

    Science.gov (United States)

    Hawley, R Scott

    2011-10-01

    The structure of the meiosis-specific synaptonemal complex, which is perhaps the central visible characteristic of meiotic prophase, has been a matter of intense interest for decades. Although a general picture of the interactions between the transverse filament proteins that create this structure has emerged from studies in a variety of organisms, a recent analysis of synaptonemal complex structure in Caenorhabditis elegans by Schild-Prüfert et al. (2011) has provided the clearest picture of the structure of the architecture of a synaptonemal complex to date. Although the transverse filaments of the worm synaptonemal complex are assembled differently then those observed in yeast, mammalian, and Drosophila synaptonemal complexes, a comparison of the four assemblies shows that achieving the overall basic structure of the synaptonemal complex is far more crucial than conserving the structures of the individual transverse filaments.

  7. Synaptonemal complex analysis of X-7 translocations in male mice

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    Ashley, T. (Univ. of Tennessee, Knoxville); Russell, L.B.; Cacheiro, N.L.A.

    1982-01-01

    The synaptonemal complexes of surface-spread spermatocytes of mice heterozygous for one of two reciprocal translations (R3 and R5) between the X and chromosome 7 have been examined by light and electron microscopy (EM). The break points of R3 were determined to be at 70% of chromosome 7, as measured from the centromere, and at 22% of the X. Translocation quadrivalents were formed almost exclusively. The break points of R5 were at 21% of chromosome 7 as measured from the centromere, and at 83% of the X. There was little indication that the break in the X interfered with sex-chromosome synapis between the 7X and Y. Univalent Y's were not observed in R3, and only seldom observed (8-14%) in R5. However, in contrast to R3, R5 formed quadrivalents relatively rarely (20% in the EM study of 100 nuclei), and hetermorphic bivalents of 7X-Y and X7-7 quite frequently (72%). Possible causes of this high bivalent frequency are discussed. Light-microsope (LM) analysis alone was found to be inadequate for interpreting synaptic configurations (quadrivalents vs. bivalents) in R5. The LM analysis was further complicated by the occurrence of nonhomologous synapsis in the heteromorphic bivalents of R5, a phenomonon easily recognized and interpreted in the EM portion of the study.

  8. Hormad1 mutation disrupts synaptonemal complex formation, recombination, and chromosome segregation in mammalian meiosis.

    Directory of Open Access Journals (Sweden)

    Yong-Hyun Shin

    2010-11-01

    Full Text Available Meiosis is unique to germ cells and essential for reproduction. During the first meiotic division, homologous chromosomes pair, recombine, and form chiasmata. The homologues connect via axial elements and numerous transverse filaments to form the synaptonemal complex. The synaptonemal complex is a critical component for chromosome pairing, segregation, and recombination. We previously identified a novel germ cell-specific HORMA domain encoding gene, Hormad1, a member of the synaptonemal complex and a mammalian counterpart to the yeast meiotic HORMA domain protein Hop1. Hormad1 is essential for mammalian gametogenesis as knockout male and female mice are infertile. Hormad1 deficient (Hormad1(-/ (- testes exhibit meiotic arrest in the early pachytene stage, and synaptonemal complexes cannot be visualized by electron microscopy. Hormad1 deficiency does not affect localization of other synaptonemal complex proteins, SYCP2 and SYCP3, but disrupts homologous chromosome pairing. Double stranded break formation and early recombination events are disrupted in Hormad1(-/ (- testes and ovaries as shown by the drastic decrease in the γH2AX, DMC1, RAD51, and RPA foci. HORMAD1 co-localizes with γH2AX to the sex body during pachytene. BRCA1, ATR, and γH2AX co-localize to the sex body and participate in meiotic sex chromosome inactivation and transcriptional silencing. Hormad1 deficiency abolishes γH2AX, ATR, and BRCA1 localization to the sex chromosomes and causes transcriptional de-repression on the X chromosome. Unlike testes, Hormad1(-/ (- ovaries have seemingly normal ovarian folliculogenesis after puberty. However, embryos generated from Hormad1(-/ (- oocytes are hyper- and hypodiploid at the 2 cell and 8 cell stage, and they arrest at the blastocyst stage. HORMAD1 is therefore a critical component of the synaptonemal complex that affects synapsis, recombination, and meiotic sex chromosome inactivation and transcriptional silencing.

  9. Hydra meiosis reveals unexpected conservation of structural synaptonemal complex proteins across metazoans

    OpenAIRE

    Fraune, Johanna; Alsheimer, Manfred; Volff, Jean-Nicolas; Busch, Karoline; Fraune, Sebastian; Bosch, Thomas C. G.; Benavente, Ricardo

    2012-01-01

    The synaptonemal complex (SC) is a key structure of meiosis, mediating the stable pairing (synapsis) of homologous chromosomes during prophase I. Its remarkable tripartite structure is evolutionarily well conserved and can be found in almost all sexually reproducing organisms. However, comparison of the different SC protein components in the common meiosis model organisms Saccharomyces cerevisiae, Arabidopsis thaliana, Caenorhabditis elegans, Drosophila melanogaster, and Mus musculus revealed...

  10. The Mr 30,000-33,000 major protein components of the lateral elements of synaptonemal complexes of the rat

    NARCIS (Netherlands)

    Lammers, H.

    1999-01-01

    Synaptonemal complexes (SCs) are intranuclear structures which are formed during meiotic prophase between homologous chromosomes. The SC consists of two protein-rich axes, either of which is found at the basis of one of the homologous chromosomes. These axes, called lateral elements (LEs),

  11. Synaptonemal complex aberrations in the pseudoautosomal region of X, Y chromosomes in irradiated hamsters

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    Allen, J.W.; Collins, B.W. [Environmental Protection Agency, Research Triangle Park, NC (United States); Poorman-Allen, P. [Wellcome Research Lab., Research Triangle Park, N.C. (United States); Sontag, M.R. [Duke Univ., Durham, NC (United States). Medical Center

    1994-05-01

    The effects of X-radiation, bleomycin and amsacrine (m-AMSA) on the meiotic chromosomes of male Armenian hamsters were determined by electron microscopic analysis of synaptonemal complex (SC) damage. Pachytene stage cells were analyzed 5 or 6 days following their treatment at putative preleptotene-leptotene stages of meiosis. Of the multiple types of SC aberrations observed to be significantly increased over control levels, lateral element breakage and synaptic anomalies were most prevalent. The focus of these studies was on the sex chromosomes which, in the Armenian hamster, reveal an unusally well-defined pseudoautosomal region. In the XY pair, radiation and chemical treatments caused certain forms of structural and synaptic anomalies which appeared to be preferentially localized to telomeric and/or crossover regions. The nature of these specific aberrations, involving breakage, bridge formation and asynapsis, is not well understood; however, their distributions are suggestive of possible relationships with sites and processes of crossing over. (author).

  12. Hydra meiosis reveals unexpected conservation of structural synaptonemal complex proteins across metazoans.

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    Fraune, Johanna; Alsheimer, Manfred; Volff, Jean-Nicolas; Busch, Karoline; Fraune, Sebastian; Bosch, Thomas C G; Benavente, Ricardo

    2012-10-09

    The synaptonemal complex (SC) is a key structure of meiosis, mediating the stable pairing (synapsis) of homologous chromosomes during prophase I. Its remarkable tripartite structure is evolutionarily well conserved and can be found in almost all sexually reproducing organisms. However, comparison of the different SC protein components in the common meiosis model organisms Saccharomyces cerevisiae, Arabidopsis thaliana, Caenorhabditis elegans, Drosophila melanogaster, and Mus musculus revealed no sequence homology. This discrepancy challenged the hypothesis that the SC arose only once in evolution. To pursue this matter we focused on the evolution of SYCP1 and SYCP3, the two major structural SC proteins of mammals. Remarkably, our comparative bioinformatic and expression studies revealed that SYCP1 and SYCP3 are also components of the SC in the basal metazoan Hydra. In contrast to previous assumptions, we therefore conclude that SYCP1 and SYCP3 form monophyletic groups of orthologous proteins across metazoans.

  13. Chromosome aberrations in F1 from irradiated male mice studied by their synaptonemal complexes

    International Nuclear Information System (INIS)

    Kalikinskaya, E.I.; Kolomiets, O.L.; Shevchenko, V.A.; Bogdanov, Yu.F.

    1986-01-01

    Possible implications of surface-spread synaptonemal complex (SC) karyotyping in analysing the causes of sterility of F 1 from irradiated male mice are demonstrated in this work. After irradiation by 137 Cs γ-rays at a dose of 5 Gy the males were mated to unirradiated females and genetic analysis of fertility in the F 1 progeny was carried out. Males with abnormal fertility were examined for the presence of chromosome aberrations in diakinesis-metaphase I and in pachytene by the method of surface-spread SC karyotyping. In most cases, SC karyotyping provides additional information and permits the detection and analysis of aberrations that are not revealed in diakinesis. Two reciprocal translocations, one X autosomal and one nonreciprocal translocation were discovered in five F 1 males studied. It is concluded that the method is efficient in detecting translocations in pachytene in partially fertile F 1 hybrids of irradiated and normal mice. (orig.)

  14. The width of the lateral element of the synaptonemal complex is determined by a multilayered organization of its components

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    Ortiz, Rosario, E-mail: r_oh@ciencias.unam.mx [Laboratorio de Microscopía Electrónica, Facultad de Ciencias, Universidad Nacional Autónoma de México, México DF 04510, México (Mexico); Kouznetsova, Anna, E-mail: Anna.Kouznetsova@ki.se [Department of Cell and Molecular Biology, Karolinska Institutet, Berzelius väg 35, 171 77 Stockholm (Sweden); Echeverría-Martínez, Olga M., E-mail: omem@ciencias.unam.mx [Laboratorio de Microscopía Electrónica, Facultad de Ciencias, Universidad Nacional Autónoma de México, México DF 04510, México (Mexico); Vázquez-Nin, Gerardo H., E-mail: vazqueznin@ciencias.unam.mx [Laboratorio de Microscopía Electrónica, Facultad de Ciencias, Universidad Nacional Autónoma de México, México DF 04510, México (Mexico); Hernández-Hernández, Abrahan, E-mail: abrahan.hernandez@ki.se [Department of Cell and Molecular Biology, Karolinska Institutet, Berzelius väg 35, 171 77 Stockholm (Sweden)

    2016-05-15

    The synaptonemal complex (SC) is a proteinaceous structure that holds the homologous chromosomes in close proximity while they exchange genetic material in a process known as meiotic recombination. This meiotic recombination leads to genetic variability in sexually reproducing organisms. The ultrastructure of the SC is studied by electron microscopy and it is observed as a tripartite structure. Two lateral elements (LE) separated by a central region (CR) confer its classical tripartite organization. The LEs are the anchoring platform for the replicated homologous chromosomes to properly exchange genetic material with one another. An accurate assembly of the LE is indispensable for the proper completion of meiosis. Ultrastructural studies suggested that the LE is organized as a multilayered unit. However, no validation of this model has been previously provided. In this ultrastructural study, by using mice with different genetic backgrounds that affect the LE width, we provide further evidence that support a multilayered organization of the LE. Additionally, we provide data suggesting additional roles of the different cohesin complex components in the structure of the LEs of the SC. - Highlights: • The lateral element of the synaptonemal complex is a multilayered structure. • The width of the lateral element in synaptonemal complex-null mice is different. • Two cohesin complex cores plus one axial element form a wild-type lateral element. • The layers of the lateral element can be analyzed in different null mice models.

  15. Sex-specific differences in the synaptonemal complex in the genus Oreochromis (Cichlidae).

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    Campos-Ramos, Rafael; Harvey, Simon C; Penman, David J

    2009-04-01

    Total synaptonemal complex (SC) lengths were estimated from Oreochromis aureus Steindachner (which has a WZ/ZZ sex determination system), O. mossambicus Peters and O. niloticus L. (both of which have XX/XY sex determination systems). The total SC length in oocytes was greater than that in spermatocytes in all three species (194 +/- 30 microm and 134 +/- 13 microm, 187 +/- 22 microm and 127 +/- 17 microm, 193 +/- 37 microm and 144 +/- 19 microm, respectively). These sex-specific differences did not appear to be influenced by the type of sex determination system (the female/male total SC length ratio was 1.45 in O. aureus, 1.47 in O. mossambicus and 1.34 in O. niloticus) and do not correlate with the lack of any overall sex-specific length differences in the current Oreochromis linkage map. Although based on data from relatively few species, there appears to be no consistent relationship between sex-specific SC lengths and linkage map lengths in fish. Neomale (hormonally masculinized genetic female) O. aureus and O. mossambicus had total SC lengths of 138 +/- 13 microm and 146 +/- 13 microm respectively, more similar to normal males than to normal females. These findings agree with data from other vertebrate species that suggest that phenotypic sex, rather than genotype, determines traits such as total SC length, chiasmata position and recombination pattern, at least for the autosomes.

  16. Fine structure of meiotic prophase chromosomes and modified synaptonemal complexes in diploid and triploid Rhoeo spathacea.

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    Lin, Y J

    1979-06-01

    The synaptonemal complex (SC) in the diploid Rhoeo consists of 2 amorphous lateral elements, each about 46.0 nm thick, and one amorphous central element about 30.0 nm thick. The central region is about 115.0 nm wide. SC in the triploid have essentially the same dimensions as those of the diploid; both lateral (46.0 nm) and central (30.0 nm) elements are amorphous, and the central region is about 117.5 nm wide. The coil, observed in both diploid and triploid, is a modified short segment of SC with several twists at the end of a synapsed bivalent that is attached to the nuclear membrane. Serial sections in a diploid cell reveal that a coil extends inwards about 3.5 micron from the nuclear membrane and makes a complete turn at a distance of every 0.5 micron. There is a correlation between the modified ends of SC and terminal chiasmata in Rhoeo. The coils might have a positive role in the process of crossing over, or alternatively might be involved in ring formation by holding chromosome ends together while chiasmata are not involved. SC are present in chromocentres of both diploid and triploid. Chromocentres in diploid and triploid are indistinguishable, and appear to be formed from the aggregation of pericentromeric heterochromatin as a result of translocations which occured close to the centromeres. 3-dimensional hypothetical pachytene configuration of the diploid is presented.

  17. The synaptonemal complex of basal metazoan hydra: more similarities to vertebrate than invertebrate meiosis model organisms.

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    Fraune, Johanna; Wiesner, Miriam; Benavente, Ricardo

    2014-03-20

    The synaptonemal complex (SC) is an evolutionarily well-conserved structure that mediates chromosome synapsis during prophase of the first meiotic division. Although its structure is conserved, the characterized protein components in the current metazoan meiosis model systems (Drosophila melanogaster, Caenorhabditis elegans, and Mus musculus) show no sequence homology, challenging the question of a single evolutionary origin of the SC. However, our recent studies revealed the monophyletic origin of the mammalian SC protein components. Many of them being ancient in Metazoa and already present in the cnidarian Hydra. Remarkably, a comparison between different model systems disclosed a great similarity between the SC components of Hydra and mammals while the proteins of the ecdysozoan systems (D. melanogaster and C. elegans) differ significantly. In this review, we introduce the basal-branching metazoan species Hydra as a potential novel invertebrate model system for meiosis research and particularly for the investigation of SC evolution, function and assembly. Also, available methods for SC research in Hydra are summarized. Copyright © 2014. Published by Elsevier Ltd.

  18. Analysis of chromosome rearrangements on the basis of synaptonemal complexes in the offspring of mice exposed to γ-rays

    International Nuclear Information System (INIS)

    Kalikinskaya, E.I.; Bogdanov, Yu.F.; Kolomiets, O.L.; Shevchenko, V.A.

    1986-01-01

    Electron-microscopic analysis of synaptonemic complexes (SC), spread on the hypophase surface, was conducted to investigate chromosome rearrangements in sterile and semisterile F 1 malemause offsprings, exposed to 5 Gy γ-rays Paralelly Chromosome rearrangement account in diakinesis-metaphase 1 was conducted using light microscope, in the same animals. During SC analysis in pachytene chromosome rearrangements were found in 63% of spermatocytes. Under chromosome analysis in diakinesis-metaphase 1 in the same animals chromosome rearrangements were found only in 32% of cells. SC analysis allows one to reveal chromosome rearrangements, which can not be revealed in diakinesis-metaphase 1

  19. Mutation of the mouse Syce1 gene disrupts synapsis and suggests a link between synaptonemal complex structural components and DNA repair.

    Directory of Open Access Journals (Sweden)

    Ewelina Bolcun-Filas

    2009-02-01

    Full Text Available In mammals, the synaptonemal complex is a structure required to complete crossover recombination. Although suggested by cytological work, in vivo links between the structural proteins of the synaptonemal complex and the proteins of the recombination process have not previously been made. The central element of the synaptonemal complex is traversed by DNA at sites of recombination and presents a logical place to look for interactions between these components. There are four known central element proteins, three of which have previously been mutated. Here, we complete the set by creating a null mutation in the Syce1 gene in mouse. The resulting disruption of synapsis in these animals has allowed us to demonstrate a biochemical interaction between the structural protein SYCE2 and the repair protein RAD51. In normal meiosis, this interaction may be responsible for promoting homologous synapsis from sites of recombination.

  20. Shaping meiotic chromosomes with SUMO: a feedback loop controls the assembly of the synaptonemal complex in budding yeast

    Directory of Open Access Journals (Sweden)

    Hideo Tsubouchi

    2016-02-01

    Full Text Available The synaptonemal complex (SC is a meiosis-specific chromosomal structure in which homologous chromosomes are intimately linked through arrays of specialized proteins called transverse filaments (TF. Widely conserved in eukaryote meiosis, the SC forms during prophase I and is essential for accurate segregation of homologous chromosomes at meiosis I. However, the basic mechanism overlooking formation and regulation of the SC has been poorly understood. By using the budding yeast Saccharomyces cerevisiae, we recently showed that SC formation is controlled through the attachment of multiple molecules of small ubiquitin-like modifier (SUMO to a regulator of TF assembly. Intriguingly, this SUMOylation is activated by TF, implicating the involvement of a positive feedback loop in the control of SC assembly. We discuss the implication of this finding and possible involvement of a similar mechanism in regulating other processes.

  1. Linkage group-chromosome correlations in Sordaria macrospora: Chromosome identification by three dimensional reconstruction of their synaptonemal complex.

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    Zickler, D; Leblon, G; Haedens, V; Collard, A; Thuriaux, P

    1984-01-01

    Reconstruction of serially sectioned zygotene and pachytene nuclei has allowed, by measuring the lengths of synaptonemal complexes, an assignment of the 7 linkage (LG) groups to the 7 chromosomes in the fungus Sordaria macrospora. The 7 LG have been established using 19 mutants showing low second division segregation frequencies. Eight chromosomal rearrangements mapped on the 7 LG were used to identify the chromosomes involved. The following one to one assignment of the 7 LG to specific chromosomes was obtained: LG a: chromosome (chr) 1, LG b: chr5, LG c: chr6, LG d: chr7, LG e: chr4, LG f: chr3 and LG g: chr2 (the chromosome carrying the nucleolus organizer region).

  2. [Autoantibody formation against the antigens of the synaptonemal complex in the syngeneic immunization of male Mus musculus].

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    Dadashev, S Ia; Gorach, G G; Kolomiets, O L

    1994-01-01

    Male mice were immunized with the suspension of synaptonemal complexes (SC) isolated from mouse spermatocytes nuclei. The indirect immunofluorescent analysis showed the active binding of sera obtained from immunized mice to SC of mouse spermatocyte spreads. At early and mid-pachytene, SC can be clearly identified in 19 autosome bivalents and in sex chromosome bivalent. According to the electron microscopic analysis, all structural elements of SC bind antibodies. Metaphase chromosomes were not stained with the immune sera. Specificity of interaction between SC components and antibodies was confirmed in a series of control experiments. Analysis of sera obtained from mice after their syngeneic immunization with isolated SC fraction suggested that certain mouse SC components induce the formation of autoantibodies. This, in turn, suggests that these SC components are meiosis-specific.

  3. HAL-2 promotes homologous pairing during Caenorhabditis elegans meiosis by antagonizing inhibitory effects of synaptonemal complex precursors.

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    Zhang, Weibin; Miley, Natasha; Zastrow, Michael S; MacQueen, Amy J; Sato, Aya; Nabeshima, Kentaro; Martinez-Perez, Enrique; Mlynarczyk-Evans, Susanna; Carlton, Peter M; Villeneuve, Anne M

    2012-01-01

    During meiosis, chromosomes align with their homologous pairing partners and stabilize this alignment through assembly of the synaptonemal complex (SC). Since the SC assembles cooperatively yet is indifferent to homology, pairing and SC assembly must be tightly coordinated. We identify HAL-2 as a key mediator in this coordination, showing that HAL-2 promotes pairing largely by preventing detrimental effects of SC precursors (SYP proteins). hal-2 mutants fail to establish pairing and lack multiple markers of chromosome movement mediated by pairing centers (PCs), chromosome sites that link chromosomes to cytoplasmic microtubules through nuclear envelope-spanning complexes. Moreover, SYP proteins load inappropriately along individual unpaired chromosomes in hal-2 mutants, and markers of PC-dependent movement and function are restored in hal-2; syp double mutants. These and other data indicate that SYP proteins can impede pairing and that HAL-2 promotes pairing predominantly but not exclusively by counteracting this inhibition, thereby enabling activation and regulation of PC function. HAL-2 concentrates in the germ cell nucleoplasm and colocalizes with SYP proteins in nuclear aggregates when SC assembly is prevented. We propose that HAL-2 functions to shepherd SYP proteins prior to licensing of SC assembly, preventing untimely interactions between SC precursors and chromosomes and allowing sufficient accumulation of precursors for rapid cooperative assembly upon homology verification.

  4. Sme4 coiled-coil protein mediates synaptonemal complex assembly, recombinosome relocalization, and spindle pole body morphogenesis.

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    Espagne, Eric; Vasnier, Christelle; Storlazzi, Aurora; Kleckner, Nancy E; Silar, Philippe; Zickler, Denise; Malagnac, Fabienne

    2011-06-28

    We identify a large coiled-coil protein, Sme4/PaMe4, that is highly conserved among the large group of Sordariales and plays central roles in two temporally and functionally distinct aspects of the fungal sexual cycle: first as a component of the meiotic synaptonemal complex (SC) and then, after disappearing and reappearing, as a component of the spindle pole body (SPB). In both cases, the protein mediates spatial juxtaposition of two major structures: linkage of homolog axes through the SC and a change in the SPB from a planar to a bent conformation. Corresponding mutants exhibit defects, respectively, in SC and SPB morphogenesis, with downstream consequences for recombination and astral-microtubule nucleation plus postmeiotic nuclear migration. Sme4 is also required for reorganization of recombination complexes in which Rad51, Mer3, and Msh4 foci relocalize from an on-axis position to a between-axis (on-SC) position concomitant with SC installation. Because involved recombinosome foci represent total recombinational interactions, these dynamics are irrespective of their designation for maturation into cross-overs or noncross-overs. The defined dual roles for Sme4 in two different structures that function at distinct phases of the sexual cycle also provide more functional links and evolutionary dynamics among the nuclear envelope, SPB, and SC.

  5. CENTRAL REGION COMPONENT1, a Novel Synaptonemal Complex Component, Is Essential for Meiotic Recombination Initiation in Rice[C][W

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    Miao, Chunbo; Tang, Ding; Zhang, Honggen; Wang, Mo; Li, Yafei; Tang, Shuzhu; Yu, Hengxiu; Gu, Minghong; Cheng, Zhukuan

    2013-01-01

    In meiosis, homologous recombination entails programmed DNA double-strand break (DSB) formation and synaptonemal complex (SC) assembly coupled with the DSB repair. Although SCs display extensive structural conservation among species, their components identified are poorly conserved at the sequence level. Here, we identified a novel SC component, designated CENTRAL REGION COMPONENT1 (CRC1), in rice (Oryza sativa). CRC1 colocalizes with ZEP1, the rice SC transverse filament protein, to the central region of SCs in a mutually dependent fashion. Consistent with this colocalization, CRC1 interacts with ZEP1 in yeast two-hybrid assays. CRC1 is orthologous to Saccharomyces cerevisiae pachytene checkpoint2 (Pch2) and Mus musculus THYROID RECEPTOR-INTERACTING PROTEIN13 (TRIP13) and may be a conserved SC component. Additionally, we provide evidence that CRC1 is essential for meiotic DSB formation. CRC1 interacts with HOMOLOGOUS PAIRING ABERRATION IN RICE MEIOSIS1 (PAIR1) in vitro, suggesting that these proteins act as a complex to promote DSB formation. PAIR2, the rice ortholog of budding yeast homolog pairing1, is required for homologous chromosome pairing. We found that CRC1 is also essential for the recruitment of PAIR2 onto meiotic chromosomes. The roles of CRC1 identified here have not been reported for Pch2 or TRIP13. PMID:23943860

  6. Central region component1, a novel synaptonemal complex component, is essential for meiotic recombination initiation in rice.

    Science.gov (United States)

    Miao, Chunbo; Tang, Ding; Zhang, Honggen; Wang, Mo; Li, Yafei; Tang, Shuzhu; Yu, Hengxiu; Gu, Minghong; Cheng, Zhukuan

    2013-08-01

    In meiosis, homologous recombination entails programmed DNA double-strand break (DSB) formation and synaptonemal complex (SC) assembly coupled with the DSB repair. Although SCs display extensive structural conservation among species, their components identified are poorly conserved at the sequence level. Here, we identified a novel SC component, designated central region component1 (CRC1), in rice (Oryza sativa). CRC1 colocalizes with ZEP1, the rice SC transverse filament protein, to the central region of SCs in a mutually dependent fashion. Consistent with this colocalization, CRC1 interacts with ZEP1 in yeast two-hybrid assays. CRC1 is orthologous to Saccharomyces cerevisiae pachytene checkpoint2 (Pch2) and Mus musculus THYROID receptor-interacting protein13 (TRIP13) and may be a conserved SC component. Additionally, we provide evidence that CRC1 is essential for meiotic DSB formation. CRC1 interacts with homologous pairing aberration in rice meiosis1 (PAIR1) in vitro, suggesting that these proteins act as a complex to promote DSB formation. PAIR2, the rice ortholog of budding yeast homolog pairing1, is required for homologous chromosome pairing. We found that CRC1 is also essential for the recruitment of PAIR2 onto meiotic chromosomes. The roles of CRC1 identified here have not been reported for Pch2 or TRIP13.

  7. Disassembled DJ-1 high molecular weight complex in cortex mitochondria from Parkinson's disease patients

    Directory of Open Access Journals (Sweden)

    Adler Charles

    2009-07-01

    Full Text Available Abstract Correction to Nural H, He P, Beach T, Sue L, Xia W, Shen Y. Disassembled DJ-1 high molecular weight complex in cortex mitochondria from Parkinson's disease patients Molecular Neurodegeneration 2009, 4:23.

  8. A novel mouse synaptonemal complex protein is essential for loading of central element proteins, recombination, and fertility.

    Directory of Open Access Journals (Sweden)

    Sabine Schramm

    2011-05-01

    Full Text Available The synaptonemal complex (SC is a proteinaceous, meiosis-specific structure that is highly conserved in evolution. During meiosis, the SC mediates synapsis of homologous chromosomes. It is essential for proper recombination and segregation of homologous chromosomes, and therefore for genome haploidization. Mutations in human SC genes can cause infertility. In order to gain a better understanding of the process of SC assembly in a model system that would be relevant for humans, we are investigating meiosis in mice. Here, we report on a newly identified component of the murine SC, which we named SYCE3. SYCE3 is strongly conserved among mammals and localizes to the central element (CE of the SC. By generating a Syce3 knockout mouse, we found that SYCE3 is required for fertility in both sexes. Loss of SYCE3 blocks synapsis initiation and results in meiotic arrest. In the absence of SYCE3, initiation of meiotic recombination appears to be normal, but its progression is severely impaired resulting in complete absence of MLH1 foci, which are presumed markers of crossovers in wild-type meiocytes. In the process of SC assembly, SYCE3 is required downstream of transverse filament protein SYCP1, but upstream of the other previously described CE-specific proteins. We conclude that SYCE3 enables chromosome loading of the other CE-specific proteins, which in turn would promote synapsis between homologous chromosomes.

  9. Defective pairing and synaptonemal complex formation in a Sordaria mutant (spo44) with a translocated segment of the nucleolar organizer.

    Science.gov (United States)

    Zickler, D; de Lares, L; Moreau, P J; Leblon, G

    1985-01-01

    The recessive meiotic mutant spo44 of Sordaria macrospora, with 90% ascospore abortion, exhibits striking effects on recombination (67% decrease), irregular segregation of the almost unpaired homologues, and a decrease in chiasma frequency in the few cases where bivalents are formed. Three-dimensional reconstructions of ten prophase nuclei indicate that pairing, as judged by the absence of fully formed synaptonemal complexes (SC), is not achieved although lateral elements (LE) assemble. The pairing failure is attributable to defects in the alignment of homologous chromosomes. The leptotene alignment seen in the wild type before SC formation was not observed in the spo44 nuclei. Dense material, considered to be precursor of SC central elements, was found scattered among the LE in two nuclei. The behaviour of spo44 substantiates the hypothesis that chromosome matching and SC formation are separable events. - The total length of the LE in the mutant is the same as in the wild type, but due to variable numbers and length of the individual LE, homologues cannot be lined up. Light microscopic observations indicate that the irregular length and number of LE is due to extensive chromosome breakage. The wild-type function corresponding to spo44 is required for both LE integrity and chromosome matching. Reconstructions of heterozygous nuclei reveal the presence of a supernumerary nucleolar organizer in one arm of chromosome 7. It is suggested that rDNA has been inserted into a gene whose function is involved in pairing or into a controlling sequence that interacts with the pairing process.

  10. Meiosis gene inventory of four ciliates reveals the prevalence of a synaptonemal complex-independent crossover pathway.

    Science.gov (United States)

    Chi, Jingyun; Mahé, Frédéric; Loidl, Josef; Logsdon, John; Dunthorn, Micah

    2014-03-01

    To establish which meiosis genes are present in ciliates, and to look for clues as to which recombination pathways may be treaded by them, four genomes were inventoried for 11 meiosis-specific and 40 meiosis-related genes. We found that the set of meiosis genes shared by Tetrahymena thermophila, Paramecium tetraurelia, Ichthyophthirius multifiliis, and Oxytricha trifallax is consistent with the prevalence of a Mus81-dependent class II crossover pathway that is considered secondary in most model eukaryotes. There is little evidence for a canonical class I crossover pathway that requires the formation of a synaptonemal complex (SC). This gene inventory suggests that meiotic processes in ciliates largely depend on mitotic repair proteins for executing meiotic recombination. We propose that class I crossovers and SCs were reduced sometime during the evolution of ciliates. Consistent with this reduction, we provide microscopic evidence for the presence only of degenerate SCs in Stylonychia mytilus. In addition, lower nonsynonymous to synonymous mutation rates of some of the meiosis genes suggest that, in contrast to most other nuclear genes analyzed so far, meiosis genes in ciliates are largely evolving at a slower rate than those genes in fungi and animals.

  11. The Pch2 AAA+ ATPase promotes phosphorylation of the Hop1 meiotic checkpoint adaptor in response to synaptonemal complex defects.

    Science.gov (United States)

    Herruzo, Esther; Ontoso, David; González-Arranz, Sara; Cavero, Santiago; Lechuga, Ana; San-Segundo, Pedro A

    2016-09-19

    Meiotic cells possess surveillance mechanisms that monitor critical events such as recombination and chromosome synapsis. Meiotic defects resulting from the absence of the synaptonemal complex component Zip1 activate a meiosis-specific checkpoint network resulting in delayed or arrested meiotic progression. Pch2 is an evolutionarily conserved AAA+ ATPase required for the checkpoint-induced meiotic block in the zip1 mutant, where Pch2 is only detectable at the ribosomal DNA array (nucleolus). We describe here that high levels of the Hop1 protein, a checkpoint adaptor that localizes to chromosome axes, suppress the checkpoint defect of a zip1 pch2 mutant restoring Mek1 activity and meiotic cell cycle delay. We demonstrate that the critical role of Pch2 in this synapsis checkpoint is to sustain Mec1-dependent phosphorylation of Hop1 at threonine 318. We also show that the ATPase activity of Pch2 is essential for its checkpoint function and that ATP binding to Pch2 is required for its localization. Previous work has shown that Pch2 negatively regulates Hop1 chromosome abundance during unchallenged meiosis. Based on our results, we propose that, under checkpoint-inducing conditions, Pch2 also possesses a positive action on Hop1 promoting its phosphorylation and its proper distribution on unsynapsed chromosome axes. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  12. Stage-specific damage to synaptonemal complexes and metaphase chromosomes induced by X rays in male mouse germ cells

    International Nuclear Information System (INIS)

    Backer, L.C.; Sontag, M.R.; Allen, J.W.

    1991-01-01

    Synaptonemal complexes (SCs) reveal mutagen-induced effects in germ cell meiotic chromosomes. The study was aimed at characterizing relationships between SC and metaphase I chromosome damage following radiation exposure at various stages of spermatogenesis. Male mice were irradiated with doses of 0, 2, or 4 Gy, and spermatocytes were harvested at times consistent with earlier exposures as spermatogonial stem cells, preleptotene cells (premeiotic DNA synthesis), or meiotic prophase cells. After stem-cell exposure, twice as many rearrangements were observed in SCs as in metaphase I chromosomes. Irradiation during premeiotic DNA synthesis resulted in dose-related increases in SC breakage and rearrangements (including novel forms) and in metaphase chromosomal aberrations. Following prophase exposure, various types and levels of SC and metaphase damage were observed. Irradiation of zygotene cells led to high frequencies of chromosome multivalents in metaphase I without a correspondingly high level of damage in preceding prophase SCs. Thus, irradiation of premeiotic and meiotic cells results in variable relationships between SC and metaphase chromosome damage

  13. The fidelity of synaptonemal complex assembly is regulated by a signaling mechanism that controls early meiotic progression.

    Science.gov (United States)

    Silva, Nicola; Ferrandiz, Nuria; Barroso, Consuelo; Tognetti, Silvia; Lightfoot, James; Telecan, Oana; Encheva, Vesela; Faull, Peter; Hanni, Simon; Furger, Andre; Snijders, Ambrosius P; Speck, Christian; Martinez-Perez, Enrique

    2014-11-24

    Proper chromosome segregation during meiosis requires the assembly of the synaptonemal complex (SC) between homologous chromosomes. However, the SC structure itself is indifferent to homology, and poorly understood mechanisms that depend on conserved HORMA-domain proteins prevent ectopic SC assembly. Although HORMA-domain proteins are thought to regulate SC assembly as intrinsic components of meiotic chromosomes, here we uncover a key role for nuclear soluble HORMA-domain protein HTP-1 in the quality control of SC assembly. We show that a mutant form of HTP-1 impaired in chromosome loading provides functionality of an HTP-1-dependent checkpoint that delays exit from homology search-competent stages until all homolog pairs are linked by the SC. Bypassing of this regulatory mechanism results in premature meiotic progression and licensing of homology-independent SC assembly. These findings identify nuclear soluble HTP-1 as a regulator of early meiotic progression, suggesting parallels with the mode of action of Mad2 in the spindle assembly checkpoint. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Phosphorylation of the Synaptonemal Complex Protein Zip1 Regulates the Crossover/Noncrossover Decision during Yeast Meiosis.

    Directory of Open Access Journals (Sweden)

    Xiangyu Chen

    2015-12-01

    Full Text Available Interhomolog crossovers promote proper chromosome segregation during meiosis and are formed by the regulated repair of programmed double-strand breaks. This regulation requires components of the synaptonemal complex (SC, a proteinaceous structure formed between homologous chromosomes. In yeast, SC formation requires the "ZMM" genes, which encode a functionally diverse set of proteins, including the transverse filament protein, Zip1. In wild-type meiosis, Zmm proteins promote the biased resolution of recombination intermediates into crossovers that are distributed throughout the genome by interference. In contrast, noncrossovers are formed primarily through synthesis-dependent strand annealing mediated by the Sgs1 helicase. This work identifies a conserved region on the C terminus of Zip1 (called Zip1 4S, whose phosphorylation is required for the ZMM pathway of crossover formation. Zip1 4S phosphorylation is promoted both by double-strand breaks (DSBs and the meiosis-specific kinase, MEK1/MRE4, demonstrating a role for MEK1 in the regulation of interhomolog crossover formation, as well as interhomolog bias. Failure to phosphorylate Zip1 4S results in meiotic prophase arrest, specifically in the absence of SGS1. This gain of function meiotic arrest phenotype is suppressed by spo11Δ, suggesting that it is due to unrepaired breaks triggering the meiotic recombination checkpoint. Epistasis experiments combining deletions of individual ZMM genes with sgs1-md zip1-4A indicate that Zip1 4S phosphorylation functions prior to the other ZMMs. These results suggest that phosphorylation of Zip1 at DSBs commits those breaks to repair via the ZMM pathway and provides a mechanism by which the crossover/noncrossover decision can be dynamically regulated during yeast meiosis.

  15. XY pair associates with the synaptonemal complex of autosomal male-sterile translocations in pachytene spermatocytes of the mouse (Mus musculus).

    Science.gov (United States)

    Forejt, J; Gregorová, S; Goetz, P

    1981-01-01

    Analysis of the chromosome behaviour at pachytene has been performed by means of the silver staining technique visualizing the synaptonemal complexes (SCs) in male mice heterozygous for the male-sterile translocations T(5;12)31Hm T(16;17)43H and T(7;19)145H, respectively. the T(9;17)138Ca male heterozygotes and T43H/T43H homozygous males were used as fertile controls. The sterile mice displayed a high frequency (about 60%) of pachytene spermatocytes with autosomal translocation configuration located in close vicinity of the XY pair. The dense round body (XAB), normally located near the X-chromosome axis in fertile males, exhibited abnormal affinity to translocation configuration in the sterile translocation heterozygotes. The incomplete synapsis of autosomes involved in translocation configuration was observed in more than 70% of the pachytene spermatocytes with the male-sterile translocations but less than 20% of the cells from T138Ca fertile male.s. A hypothesis relating the spermatogenic arrest of carriers of male-sterile rearrangements to the presumed interference with X chromosome inactivation in male meiosis is discussed.

  16. Assembly/disassembly of a complex icosahedral virus to incorporate heterologous nucleic acids

    Science.gov (United States)

    Pascual, Elena; Mata, Carlos P.; Carrascosa, José L.; Castón, José R.

    2017-12-01

    Hollow protein containers are widespread in nature, and include virus capsids as well as eukaryotic and bacterial complexes. Protein cages are studied extensively for applications in nanotechnology, nanomedicine and materials science. Their inner and outer surfaces can be modified chemically or genetically, and the internal cavity can be used to template, store and/or arrange molecular cargos. Virus capsids and virus-like particles (VLP, noninfectious particles) provide versatile platforms for nanoscale bioengineering. Study of capsid protein self-assembly into monodispersed particles, and of VLP structure and biophysics is necessary not only to understand natural processes, but also to infer how these platforms can be redesigned to furnish novel functional VLP. Here we address the assembly dynamics of infectious bursal disease virus (IBDV), a complex icosahedral virus. IBDV has a ~70 nm-diameter T  =  13 capsid with VP2 trimers as the only structural subunits. During capsid assembly, VP2 is synthesized as a precursor (pVP2) whose C terminus is cleaved. The pVP2 C terminus has an amphipathic helix that controls VP2 polymorphism. In the absence of the VP3 scaffolding protein, necessary for control of assembly, 466/456-residue pVP2 intermediates bearing this helix assemble into VLP only when expressed with an N-terminal His6 tag (the HT-VP2-466 protein). HT-VP2-466 capsids are optimal for genetic insertion of proteins (cargo space ~78 000 nm3). We established an in vitro assembly/disassembly system of HT-VP2-466-based VLP for heterologous nucleic acid packaging and/or encapsulation of drugs and other molecules. HT-VP2-466 (empty) capsids were disassembled and reassembled by dialysis against low-salt/basic pH and high-salt/acid pH buffers, respectively, thus illustrating the reversibility in vitro of IBDV capsid assembly. HT-VP2-466 VLP also packed heterologous DNA by non-specific confinement during assembly. These and previous results establish the bases

  17. Synaptonemal complex analysis of interracial hybrids between the Moscow and Neroosa chromosomal races of the common shrew Sorex araneus showing regular formation of a complex meiotic configuration (ring-of-four).

    Science.gov (United States)

    Matveevsky, Sergey N; Pavlova, Svetlana V; Maret M Acaeva; Oxana L Kolomiets

    2012-01-01

    Immunocytochemical and electron microscopic analysis of synaptonemal complexes (SCs) was carried out for the first time in homozygotes and complex Robertsonian heterozygotes (hybrids) of the common shrew, Sorex araneus Linnaeus, 1758, from a newly discovered hybrid zone between the Moscow and the Neroosa chromosomal races. These races differ in four monobrachial homologous metacentrics, and closed SC tetravalent is expected to be formed in meiosis of a hybrid. Indeed, such a multivalent was found at meiotic prophase I in hybrids. Interactions between multivalent and both autosomes and/or the sex chromosomes were observed. For the first time we have used immunocytochemical techniques to analyse asynapsis in Sorex araneus and show that the multivalent pairs in an orderly fashion with complete synapsis. Despite some signs of spermatocytes arrested in the meiotic prophase I, hybrids had large number of active sperm. Thus, Moscow - Neroosa hybrid males that form a ring-of-four meiotic configuration are most likely not sterile. Our results support previous demonstrations that monobrachial homology of metacentrics of the common shrew does not lead to complete reproductive isolation between parapatric chromosomal races of the species.

  18. Synaptonemal complex analysis of interracial hybrids between the Moscow and Neroosa chromosomal races of the common shrew Sorex araneus showing regular formation of a complex meiotic configuration (ring-of-four

    Directory of Open Access Journals (Sweden)

    Sergey Matveevsky

    2012-09-01

    Full Text Available Immunocytochemical and electron microscopic analysis of synaptonemal complexes (SCs was carried out for the first time in homozygotes and complex Robertsonian heterozygotes (hybrids of the common shrew, Sorex araneus Linnaeus, 1758, from a newly discovered hybrid zone between the Moscow and the Neroosa chromosomal races. These races differ in four monobrachial homologous metacentrics, and closed SC tetravalent is expected to be formed in meiosis of a hybrid. Indeed, such a multivalent was found at meiotic prophase I in hybrids. Interactions between multivalent and both autosomes and/or the sex chromosomes were observed. For the first time we have used immunocytochemical techniques to analyse asynapsis in S. araneus and show that the multivalent pairs in an orderly fashion with complete synapsis. Despite some signs of spermatocytes arrested in the meiotic prophase I, hybrids had large number of active sperm. Thus, Moscow – Neroosa hybrid males that form a ring-of-four meiotic configuration are most likely not sterile. Our results support previous demonstrations that monobrachial homology of metacentrics of the common shrew does not lead to complete reproductive isolation between parapatric chromosomal races of the species.

  19. Ahp2 (Hop2) function in Arabidopsis thaliana (Ler) is required for stabilization of close alignment and synaptonemal complex formation except for the two short arms that contain nucleolus organizer regions.

    Science.gov (United States)

    Stronghill, P; Pathan, N; Ha, H; Supijono, E; Hasenkampf, C

    2010-08-01

    A cytological comparative analysis of male meiocytes was performed for Arabidopsis wild type and the ahp2 (hop2) mutant with emphasis on ahp2's largely uncharacterized prophase I. Leptotene progression appeared normal in ahp2 meiocytes; chromosomes exhibited regular axis formation and assumed a typical polarized nuclear organization. In contrast, 4',6'-diamidino-2-phenylindole-stained ahp2 pachytene chromosome spreads demonstrated a severe reduction in stabilized pairing. However, transmission electron microscopy (TEM) analysis of sections from meiocytes revealed that ahp2 chromosome axes underwent significant amounts of close alignment (44% of total axis). This apparent paradox strongly suggests that the Ahp2 protein is involved in the stabilization of homologous chromosome close alignment. Fluorescent in situ hybridization in combination with Zyp1 immunostaining revealed that ahp2 mutants undergo homologous synapsis of the nucleolus-organizer-region-bearing short arms of chromosomes 2 and 4, despite the otherwise "nucleus-wide" lack of stabilized pairing. The duration of ahp2 zygotene was significantly prolonged and is most likely due to difficulties in chromosome alignment stabilization and subsequent synaptonemal complex formation. Ahp2 and Mnd1 proteins have previously been shown, "in vitro," to form a heterodimer. Here we show, "in situ," that the Ahp2 and Mnd1 proteins are synchronous in their appearance and disappearance from meiotic chromosomes. Both the Ahp2 and Mnd1 proteins localize along the chromosomal axis. However, localization of the Ahp2 protein was entirely foci-based whereas Mnd1 protein exhibited an immunostaining pattern with some foci along the axis and a diffuse staining for the rest of the chromosome.

  20. Modeling operational behavior of a disassembly line

    Science.gov (United States)

    Kizilkaya, Elif A.; Gupta, Surendra M.

    2004-12-01

    In this paper we present a dynamic kanban (pull) system specifically developed for disassembly lines. This type of kanban system is much more complex than the traditional kanban system used in assembly lines. For instance, unlike the assembly line where the external demand occurs only at the last station, the demands in the disassembly case also occur at any of the intermittent stations. The reason is that as a product moves on the disassembly line, various parts are disassembled at every station and accumulated at that station. Therefore, there are as many demand sources as there are number of parts. We consider a case example involving the end-of-life products. Based on the precedence relationships and other criteria such as hazardous properties of the parts, we balance the disassembly line. The results of the disassembly line-balancing problem (DLBP) are used as input to the proposed dynamic kanban system for disassembly line (DKSDL). We compare the performance of the DKSDL to the modified kanban system for disassembly line (MKSDL), which was previously introduced by the authors. We show, via simulation, that the DKSDL is far superior to MKSDL considered.

  1. LRRK2 phosphorylates pre-synaptic N-ethylmaleimide sensitive fusion (NSF) protein enhancing its ATPase activity and SNARE complex disassembling rate.

    Science.gov (United States)

    Belluzzi, Elisa; Gonnelli, Adriano; Cirnaru, Maria-Daniela; Marte, Antonella; Plotegher, Nicoletta; Russo, Isabella; Civiero, Laura; Cogo, Susanna; Carrion, Maria Perèz; Franchin, Cinzia; Arrigoni, Giorgio; Beltramini, Mariano; Bubacco, Luigi; Onofri, Franco; Piccoli, Giovanni; Greggio, Elisa

    2016-01-13

    Lrrk2, a gene linked to Parkinson's disease, encodes a large scaffolding protein with kinase and GTPase activities implicated in vesicle and cytoskeletal-related processes. At the presynaptic site, LRRK2 associates with synaptic vesicles through interaction with a panel of presynaptic proteins. Here, we show that LRRK2 kinase activity influences the dynamics of synaptic vesicle fusion. We therefore investigated whether LRRK2 phosphorylates component(s) of the exo/endocytosis machinery. We have previously observed that LRRK2 interacts with NSF, a hexameric AAA+ ATPase that couples ATP hydrolysis to the disassembling of SNARE proteins allowing them to enter another fusion cycle during synaptic exocytosis. Here, we demonstrate that NSF is a substrate of LRRK2 kinase activity. LRRK2 phosphorylates full-length NSF at threonine 645 in the ATP binding pocket of D2 domain. Functionally, NSF phosphorylated by LRRK2 displays enhanced ATPase activity and increased rate of SNARE complex disassembling. Substitution of threonine 645 with alanine abrogates LRRK2-mediated increased ATPase activity. Given that the most common Parkinson's disease LRRK2 G2019S mutation displays increased kinase activity, our results suggest that mutant LRRK2 may impair synaptic vesicle dynamics via aberrant phosphorylation of NSF.

  2. AGC-2 Disassembly Report

    Energy Technology Data Exchange (ETDEWEB)

    William Windes

    2014-05-01

    The Next Generation Nuclear Plant (NGNP) Graphite Research and Development (R&D) Program is currently measuring irradiated material properties for predicting the behavior and operating performance of new nuclear graphite grades available for use within the cores of new very high temperature reactor designs. The Advanced Graphite Creep (AGC) experiment, consisting of six irradiation capsules, will generate irradiated graphite performance data for NGNP reactor operating conditions. The AGC experiment is designed to determine the changes to specific material properties such as thermal diffusivity, thermal expansion, elastic modulus, mechanical strength, irradiation induced dimensional change rate, and irradiation creep for a wide variety of nuclear grade graphite types over a range of high temperature, and moderate doses. A series of six capsules containing graphite test specimens will be used to expose graphite test samples to a dose range from 1 to 7 dpa at three different temperatures (600, 900, and 1200°C) as described in the Graphite Technology Development Plan. Since irradiation induced creep within graphite components is considered critical to determining the operational life of the graphite core, some of the samples will also be exposed to an applied load to determine the creep rate for each graphite type under both temperature and neutron flux. All six AGC capsules in the experiment will be irradiated in the Advanced Test Reactor (ATR). AGC-1 and AGC-2 will be irradiated in the south flux trap and AGC-3–AGC-6 will be irradiated in the east flux trap. The change in flux traps is due to NGNP irradiation priorities requiring the AGC experiment to be moved to accommodate Fuel irradiation experiments. After irradiation, all six AGC capsules will be cooled in the ATR Canal, sized for shipment, and shipped to the Materials and Fuels Complex (MFC) where the capsule will be disassembled in the Hot Fuel Examination Facility (HFEF). During disassembly, the metallic

  3. Inositol hexakisphosphate kinase-1 mediates assembly/disassembly of the CRL4–signalosome complex to regulate DNA repair and cell death

    Science.gov (United States)

    Rao, Feng; Xu, Jing; Khan, A. Basit; Gadalla, Moataz M.; Cha, Jiyoung Y.; Xu, Risheng; Tyagi, Richa; Dang, Yongjun; Chakraborty, Anutosh; Snyder, Solomon H.

    2014-01-01

    Inositol polyphosphates containing an energetic pyrophosphate bond are formed primarily by a family of three inositol hexakisphosphate (IP6) kinases (IP6K1–3). The Cullin-RING ubiquitin ligases (CRLs) regulate diverse biological processes through substrate ubiquitylation. CRL4, comprising the scaffold Cullin 4A/B, the E2-interacting Roc1/2, and the adaptor protein damage-specific DNA-binding protein 1, is activated by DNA damage. Basal CRL4 activity is inhibited by binding to the COP9 signalosome (CSN). UV radiation and other stressors dissociate the complex, leading to E3 ligase activation, but signaling events that trigger signalosome dissociation from CRL4 have been unclear. In the present study, we show that, under basal conditions, IP6K1 forms a ternary complex with CSN and CRL4 in which IP6K1 and CRL4 are inactive. UV dissociates IP6K1 to generate IP7, which then dissociates CSN–CRL4 to activate CRL4. Thus, IP6K1 is a novel CRL4 subunit that transduces UV signals to mediate disassembly of the CRL4–CSN complex, thereby regulating nucleotide excision repair and cell death. PMID:25349427

  4. Retention of habitat complexity minimizes disassembly of reef fish communities following disturbance: a large-scale natural experiment.

    Directory of Open Access Journals (Sweden)

    Michael J Emslie

    Full Text Available High biodiversity ecosystems are commonly associated with complex habitats. Coral reefs are highly diverse ecosystems, but are under increasing pressure from numerous stressors, many of which reduce live coral cover and habitat complexity with concomitant effects on other organisms such as reef fishes. While previous studies have highlighted the importance of habitat complexity in structuring reef fish communities, they employed gradient or meta-analyses which lacked a controlled experimental design over broad spatial scales to explicitly separate the influence of live coral cover from overall habitat complexity. Here a natural experiment using a long term (20 year, spatially extensive (∼ 115,000 kms(2 dataset from the Great Barrier Reef revealed the fundamental importance of overall habitat complexity for reef fishes. Reductions of both live coral cover and habitat complexity had substantial impacts on fish communities compared to relatively minor impacts after major reductions in coral cover but not habitat complexity. Where habitat complexity was substantially reduced, species abundances broadly declined and a far greater number of fish species were locally extirpated, including economically important fishes. This resulted in decreased species richness and a loss of diversity within functional groups. Our results suggest that the retention of habitat complexity following disturbances can ameliorate the impacts of coral declines on reef fishes, so preserving their capacity to perform important functional roles essential to reef resilience. These results add to a growing body of evidence about the importance of habitat complexity for reef fishes, and represent the first large-scale examination of this question on the Great Barrier Reef.

  5. Illustrating the disassembly of 3D models

    KAUST Repository

    Guo, Jianwei

    2013-06-11

    We present a framework for the automatic disassembly of 3D man-made models and the illustration of the disassembly process. Given an assembled 3D model, we first analyze the individual parts using sharp edge loops and extract the contact faces between each pair of neighboring parts. The contact faces are then used to compute the possible moving directions of each part. We then present a simple algorithm for clustering the sets of the individual parts into meaningful sub-assemblies, which can be used for a hierarchical decomposition. We take the stability of sub-assemblies into account during the decomposition process by considering the upright orientation of the input models. Our framework also provides a user-friendly interface to enable the superimposition of the constraints for the decomposition. Finally, we visualize the disassembly process by generating an animated sequence. The experiments demonstrate that our framework works well for a variety of complex models. © 2013 Elsevier Ltd.

  6. Design for Disassembly

    DEFF Research Database (Denmark)

    Beim, Anne

    2018-01-01

    ‘Design for Disassembly’ is becoming a familiar part of discourses on environmental strategies for construction and sustainable design. The concept originates in industrial design and pertains to a wide range of strategies for reuse and recycling, all of which highlight a whole-of-life approach t...... to materials and buildings. Design for Disassembly is particularly relevant to prefabricated and industrialized construction; as such methodologies already contain within them the possibility for easy deconstruction, whether for maintenance, refurbishment or reuse....

  7. A symbolic methodology to improve disassembly process design.

    Science.gov (United States)

    Rios, Pedro; Blyler, Leslie; Tieman, Lisa; Stuart, Julie Ann; Grant, Ed

    2003-12-01

    Millions of end-of-life electronic components are retired annually due to the proliferation of new models and their rapid obsolescence. The recovery of resources such as plastics from these goods requires their disassembly. The time required for each disassembly and its associated cost is defined by the operator's familiarity with the product design and its complexity. Since model proliferation serves to complicate an operator's learning curve, it is worthwhile to investigate the benefits to be gained in a disassembly operator's preplanning process. Effective disassembly process design demands the application of green engineering principles, such as those developed by Anastas and Zimmerman (Environ. Sci. Technol. 2003, 37, 94A-101A), which include regard for product complexity, structural commonality, separation energy, material value, and waste prevention. This paper introduces the concept of design symbolsto help the operator more efficiently survey product complexity with respect to location and number of fasteners to remove a structure that is common to all electronics: the housing. With a sample of 71 different computers, printers, and monitors, we demonstrate that appropriate symbols reduce the total disassembly planning time by 13.2 min. Such an improvement could well make efficient the separation of plastic that would otherwise be destined for waste-to-energy or landfill. The symbolic methodology presented may also improve Design for Recycling and Design for Maintenance and Support.

  8. The assembly and disassembly of ecological networks.

    Science.gov (United States)

    Bascompte, Jordi; Stouffer, Daniel B

    2009-06-27

    Global change has created a severe biodiversity crisis. Species are driven extinct at an increasing rate, and this has the potential to cause further coextinction cascades. The rate and shape of these coextinction cascades depend very much on the structure of the networks of interactions across species. Understanding network structure and how it relates to network disassembly, therefore, is a priority for system-level conservation biology. This process of network collapse may indeed be related to the process of network build-up, although very little is known about both processes and even less about their relationship. Here we review recent work that provides some preliminary answers to these questions. First, we focus on network assembly by emphasizing temporal processes at the species level, as well as the structural building blocks of complex ecological networks. Second, we focus on network disassembly as a consequence of species extinctions or habitat loss. We conclude by emphasizing some general rules of thumb that can help in building a comprehensive framework to understand the responses of ecological networks to global change.

  9. Elongation factor Ts directly facilitates the formation and disassembly of the Escherichia coli elongation factor Tu·GTP·aminoacyl-tRNA ternary complex.

    Science.gov (United States)

    Burnett, Benjamin J; Altman, Roger B; Ferrao, Ryan; Alejo, Jose L; Kaur, Navdep; Kanji, Joshua; Blanchard, Scott C

    2013-05-10

    Aminoacyl-tRNA (aa-tRNA) enters the ribosome in a ternary complex with the G-protein elongation factor Tu (EF-Tu) and GTP. EF-Tu·GTP·aa-tRNA ternary complex formation and decay rates are accelerated in the presence of the nucleotide exchange factor elongation factor Ts (EF-Ts). EF-Ts directly facilitates the formation and disassociation of ternary complex. This system demonstrates a novel function of EF-Ts. Aminoacyl-tRNA enters the translating ribosome in a ternary complex with elongation factor Tu (EF-Tu) and GTP. Here, we describe bulk steady state and pre-steady state fluorescence methods that enabled us to quantitatively explore the kinetic features of Escherichia coli ternary complex formation and decay. The data obtained suggest that both processes are controlled by a nucleotide-dependent, rate-determining conformational change in EF-Tu. Unexpectedly, we found that this conformational change is accelerated by elongation factor Ts (EF-Ts), the guanosine nucleotide exchange factor for EF-Tu. Notably, EF-Ts attenuates the affinity of EF-Tu for GTP and destabilizes ternary complex in the presence of non-hydrolyzable GTP analogs. These results suggest that EF-Ts serves an unanticipated role in the cell of actively regulating the abundance and stability of ternary complex in a manner that contributes to rapid and faithful protein synthesis.

  10. Elongation Factor Ts Directly Facilitates the Formation and Disassembly of the Escherichia coli Elongation Factor Tu·GTP·Aminoacyl-tRNA Ternary Complex*

    Science.gov (United States)

    Burnett, Benjamin J.; Altman, Roger B.; Ferrao, Ryan; Alejo, Jose L.; Kaur, Navdep; Kanji, Joshua; Blanchard, Scott C.

    2013-01-01

    Aminoacyl-tRNA enters the translating ribosome in a ternary complex with elongation factor Tu (EF-Tu) and GTP. Here, we describe bulk steady state and pre-steady state fluorescence methods that enabled us to quantitatively explore the kinetic features of Escherichia coli ternary complex formation and decay. The data obtained suggest that both processes are controlled by a nucleotide-dependent, rate-determining conformational change in EF-Tu. Unexpectedly, we found that this conformational change is accelerated by elongation factor Ts (EF-Ts), the guanosine nucleotide exchange factor for EF-Tu. Notably, EF-Ts attenuates the affinity of EF-Tu for GTP and destabilizes ternary complex in the presence of non-hydrolyzable GTP analogs. These results suggest that EF-Ts serves an unanticipated role in the cell of actively regulating the abundance and stability of ternary complex in a manner that contributes to rapid and faithful protein synthesis. PMID:23539628

  11. Simulation-based disassembly systems design

    Science.gov (United States)

    Ohlendorf, Martin; Herrmann, Christoph; Hesselbach, Juergen

    2004-02-01

    Recycling of Waste of Electrical and Electronic Equipment (WEEE) is a matter of actual concern, driven by economic, ecological and legislative reasons. Here, disassembly as the first step of the treatment process plays a key role. To achieve sustainable progress in WEEE disassembly, the key is not to limit analysis and planning to merely disassembly processes in a narrow sense, but to consider entire disassembly plants including additional aspects such as internal logistics, storage, sorting etc. as well. In this regard, the paper presents ways of designing, dimensioning, structuring and modeling different disassembly systems. Goal is to achieve efficient and economic disassembly systems that allow recycling processes complying with legal requirements. Moreover, advantages of applying simulation software tools that are widespread and successfully utilized in conventional industry sectors are addressed. They support systematic disassembly planning by means of simulation experiments including consecutive efficiency evaluation. Consequently, anticipatory recycling planning considering various scenarios is enabled and decisions about which types of disassembly systems evidence appropriateness for specific circumstances such as product spectrum, throughput, disassembly depth etc. is supported. Furthermore, integration of simulation based disassembly planning in a holistic concept with configuration of interfaces and data utilization including cost aspects is described.

  12. Disassembly and Sanitization of Classified Matter

    International Nuclear Information System (INIS)

    Stockham, Dwight J.; Saad, Max P.

    2008-01-01

    The Disassembly Sanitization Operation (DSO) process was implemented to support weapon disassembly and disposition by using recycling and waste minimization measures. This process was initiated by treaty agreements and reconfigurations within both the DOD and DOE Complexes. The DOE is faced with disassembling and disposing of a huge inventory of retired weapons, components, training equipment, spare parts, weapon maintenance equipment, and associated material. In addition, regulations have caused a dramatic increase in the need for information required to support the handling and disposition of these parts and materials. In the past, huge inventories of classified weapon components were required to have long-term storage at Sandia and at many other locations throughout the DoE Complex. These materials are placed in onsite storage unit due to classification issues and they may also contain radiological and/or hazardous components. Since no disposal options exist for this material, the only choice was long-term storage. Long-term storage is costly and somewhat problematic, requiring a secured storage area, monitoring, auditing, and presenting the potential for loss or theft of the material. Overall recycling rates for materials sent through the DSO process have enabled 70 to 80% of these components to be recycled. These components are made of high quality materials and once this material has been sanitized, the demand for the component metals for recycling efforts is very high. The DSO process for NGPF, classified components established the credibility of this technique for addressing the long-term storage requirements of the classified weapons component inventory. The success of this application has generated interest from other Sandia organizations and other locations throughout the complex. Other organizations are requesting the help of the DSO team and the DSO is responding to these requests by expanding its scope to include Work-for- Other projects. For example

  13. An Entropy-Based Adaptive Hybrid Particle Swarm Optimization for Disassembly Line Balancing Problems

    Directory of Open Access Journals (Sweden)

    Shanli Xiao

    2017-11-01

    Full Text Available In order to improve the product disassembly efficiency, the disassembly line balancing problem (DLBP is transformed into a problem of searching for the optimum path in the directed and weighted graph by constructing the disassembly hierarchy information graph (DHIG. Then, combining the characteristic of the disassembly sequence, an entropy-based adaptive hybrid particle swarm optimization algorithm (AHPSO is presented. In this algorithm, entropy is introduced to measure the changing tendency of population diversity, and the dimension learning, crossover and mutation operator are used to increase the probability of producing feasible disassembly solutions (FDS. Performance of the proposed methodology is tested on the primary problem instances available in the literature, and the results are compared with other evolutionary algorithms. The results show that the proposed algorithm is efficient to solve the complex DLBP.

  14. Microcanonical simulation of nuclear disassembly

    International Nuclear Information System (INIS)

    Koonin, S.E.; Randrup, J.

    1986-01-01

    There is considerable interest in the disassembly of the hot nuclear matter produced in high-energy nuclear collisions. A particular stimulus has been the prospect of observing a nuclear liquid-gas phase transition. On rather general grounds, such a transition is expected to occur in nuclear matter at subsaturation densities with temperatures of 10-20 MeV. However, virtually all previous discussions of this phenomenon have been based on thermodynamical considerations valid for infinite, non-interacting systems and the qualitative validity of the results has not been ascertained for the relatively small, finite, interacting systems of practical relevance. Nor is it clear how the occurrence of the phase transition will manifest itself in the asymptotically observed fragment distribution. To progress in these matters, the authors have formulated a microcanonical simulation of the disassembly process, including interfragment interactions. It is a natural refinement of the grand canonical model first presented in [1] and further developed in [2] and is also a exact version of the model developed in [3] for the generation of complete multifragment events in medium-energy collisions. In this contribution, the authors give a brief description of the key ingredients in the model and its numerical implementation

  15. Illustrating the disassembly of 3D models

    KAUST Repository

    Guo, Jianwei; Yan, Dongming; Li, Er; Dong, Weiming; Wonka, Peter; Zhang, Xiaopeng

    2013-01-01

    We present a framework for the automatic disassembly of 3D man-made models and the illustration of the disassembly process. Given an assembled 3D model, we first analyze the individual parts using sharp edge loops and extract the contact faces

  16. A methodological approach for designing and sequencing product families in Reconfigurable Disassembly Systems

    Directory of Open Access Journals (Sweden)

    Ignacio Eguia

    2011-10-01

    Full Text Available Purpose: A Reconfigurable Disassembly System (RDS represents a new paradigm of automated disassembly system that uses reconfigurable manufacturing technology for fast adaptation to changes in the quantity and mix of products to disassemble. This paper deals with a methodology for designing and sequencing product families in RDS. Design/methodology/approach: The methodology is developed in a two-phase approach, where products are first grouped into families and then families are sequenced through the RDS, computing the required machines and modules configuration for each family. Products are grouped into families based on their common features using a Hierarchical Clustering Algorithm. The optimal sequence of the product families is calculated using a Mixed-Integer Linear Programming model minimizing reconfigurability and operational costs. Findings: This paper is focused to enable reconfigurable manufacturing technologies to attain some degree of adaptability during disassembly automation design using modular machine tools. Research limitations/implications: The MILP model proposed for the second phase is similar to the well-known Travelling Salesman Problem (TSP and therefore its complexity grows exponentially with the number of products to disassemble. In real-world problems, which a higher number of products, it may be advisable to solve the model approximately with heuristics. Practical implications: The importance of industrial recycling and remanufacturing is growing due to increasing environmental and economic pressures. Disassembly is an important part of remanufacturing systems for reuse and recycling purposes. Automatic disassembly techniques have a growing number of applications in the area of electronics, aerospace, construction and industrial equipment. In this paper, a design and scheduling approach is proposed to apply in this area. Originality/value: This paper presents a new concept called Reconfigurable Disassembly System

  17. Disassembly automation automated systems with cognitive abilities

    CERN Document Server

    Vongbunyong, Supachai

    2015-01-01

    This book presents a number of aspects to be considered in the development of disassembly automation, including the mechanical system, vision system and intelligent planner. The implementation of cognitive robotics increases the flexibility and degree of autonomy of the disassembly system. Disassembly, as a step in the treatment of end-of-life products, can allow the recovery of embodied value left within disposed products, as well as the appropriate separation of potentially-hazardous components. In the end-of-life treatment industry, disassembly has largely been limited to manual labor, which is expensive in developed countries. Automation is one possible solution for economic feasibility. The target audience primarily comprises researchers and experts in the field, but the book may also be beneficial for graduate students.

  18. Meiotic Clade AAA ATPases: Protein Polymer Disassembly Machines.

    Science.gov (United States)

    Monroe, Nicole; Hill, Christopher P

    2016-05-08

    Meiotic clade AAA ATPases (ATPases associated with diverse cellular activities), which were initially grouped on the basis of phylogenetic classification of their AAA ATPase cassette, include four relatively well characterized family members, Vps4, spastin, katanin and fidgetin. These enzymes all function to disassemble specific polymeric protein structures, with Vps4 disassembling the ESCRT-III polymers that are central to the many membrane-remodeling activities of the ESCRT (endosomal sorting complexes required for transport) pathway and spastin, katanin p60 and fidgetin affecting multiple aspects of cellular dynamics by severing microtubules. They share a common domain architecture that features an N-terminal MIT (microtubule interacting and trafficking) domain followed by a single AAA ATPase cassette. Meiotic clade AAA ATPases function as hexamers that can cycle between the active assembly and inactive monomers/dimers in a regulated process, and they appear to disassemble their polymeric substrates by translocating subunits through the central pore of their hexameric ring. Recent studies with Vps4 have shown that nucleotide-induced asymmetry is a requirement for substrate binding to the pore loops and that recruitment to the protein lattice via MIT domains also relieves autoinhibition and primes the AAA ATPase cassettes for substrate binding. The most striking, unifying feature of meiotic clade AAA ATPases may be their MIT domain, which is a module that is found in a wide variety of proteins that localize to ESCRT-III polymers. Spastin also displays an adjacent microtubule binding sequence, and the presence of both ESCRT-III and microtubule binding elements may underlie the recent findings that the ESCRT-III disassembly function of Vps4 and the microtubule-severing function of spastin, as well as potentially katanin and fidgetin, are highly coordinated. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. The effect of sudden server breakdown on the performance of a disassembly line

    Science.gov (United States)

    Udomsawat, Gun; Gupta, Surendra M.

    2005-11-01

    Product and material recovery relies on the disassembly process to separate target components or materials from the end-of-life (EOL) products. Disassembly line is especially effective when products in large quantity are disassembled. Unlike an assembly line, a disassembly line is more complex and is subjected to numerous uncertainties including stochastic and multi-level arrivals of component demands, stochastic arrival times for EOL products, and process interruption due to equipment failure. These factors seriously impair the control mechanism in the disassembly line. A common production control mechanism is the traditional push system (TPS). TPS responds to the aforementioned complications by carrying substantial amounts of inventories. An alternative control mechanism is a newly developed multi-kanban pull system (MKS) that relies on dynamic routing of kanbans, which tends to minimize the system's inventories while maintaining demand serviceability. In this paper we explore the impact of sudden breakdown of server on the performance of a disassembly line. We compare the overall performances of the TPS and MKS by considering two scenarios. We present the solution procedure and results for these cases.

  20. Generation of control sequences for a pilot-disassembly system

    Science.gov (United States)

    Seliger, Guenther; Kim, Hyung-Ju; Keil, Thomas

    2002-02-01

    Closing the product and material cycles has emerged as a paradigm for industry in the 21st century. Disassembly plays a key role in a life cycle economy since it enables the recovery of resources. A partly automated disassembly system should adapt to a large variety of products and different degrees of devaluation. Also the amounts of products to be disassembled can vary strongly. To cope with these demands an approach to generate on-line disassembly control sequences will be presented. In order to react on these demands the technological feasibility is considered within a procedure for the generation of disassembly control sequences. Procedures are designed to find available and technologically feasible disassembly processes. The control system is formed by modularised and parameterised control units in the cell level within the entire control architecture. In the first development stage product and process analyses at the sample product washing machine were executed. Furthermore a generalized disassembly process was defined. Afterwards these processes were structured in primary and secondary functions. In the second stage the disassembly control at the technological level was investigated. Factors were the availability of the disassembly tools and the technological feasibility of the disassembly processes within the disassembly system. Technical alternative disassembly processes are determined as a result of availability of the tools and technological feasibility of processes. The fourth phase was the concept for the generation of the disassembly control sequences. The approach will be proved in a prototypical disassembly system.

  1. Recycling of electrical motors by automatic disassembly

    Science.gov (United States)

    Karlsson, Björn; Järrhed, Jan-Ove

    2000-04-01

    This paper presents a robotized workstation for end-of-life treatment of electrical motors with an electrical effect of about 1 kW. These motors can, for example, be found in washing machines and in industry. There are two main steps in the work. The first step is an inspection whereby the functionality of the motor is checked and classification either for re-use or for disassembly is done. In the second step the motors classified for disassembly are disassembled in a robotized automatic station. In the initial step measurements are performed during a start-up sequence of about 1 s. By measuring the rotation speed and the current and voltage of the three phases of the motor classification for either reuse or disassembly can be done. During the disassembly work, vision data are fused in order to classify the motors according to their type. The vision system also feeds the control system of the robot with various object co-ordinates, to facilitate correct operation of the robot. Finally, tests with a vision system and eddy-current equipment are performed to decide whether all copper has been removed from the stator.

  2. Nuclear fuel bundle disassembly and assembly tool

    International Nuclear Information System (INIS)

    Yates, J.; Long, J.W.

    1975-01-01

    A nuclear power reactor fuel bundle is described which has a plurality of tubular fuel rods disposed in parallel array between two transverse tie plates. It is secured against disassembly by one or more locking forks which engage slots in tie rods which position the transverse plates. Springs mounted on the fuel and tie rods are compressed when the bundle is assembled thereby maintaining a continual pressure against the locking forks. Force applied in opposition to the springs permits withdrawal of the locking forks so that one tie plate may be removed, giving access to the fuel rods. An assembly and disassembly tool facilitates removal of the locking forks when the bundle is to be disassembled and the placing of the forks during assembly of the bundle. (U.S.)

  3. Methods for otpimum and near optimum disassembly sequencing

    NARCIS (Netherlands)

    Lambert, A.J.D.; Gupta, S.M.

    2008-01-01

    This paper considers disassembly sequencing problems subjected to sequence dependent disassembly costs. In practice, the methods for dealing with such problems rely mainly on metaheuristic and heuristic methods, which intrinsically generate suboptimum solutions. Exact methods are NP-hard and

  4. Task-failure-driven rebalancing of disassembly lines

    OpenAIRE

    Altekin, Fatma Tevhide; Akkan, Can

    2011-01-01

    Many reverse-logistics systems that collect and reprocess end-of-life products require a disassembly stage. The nature of variability in incoming products, and damages, which are more likely to occur during disassembly than assembly, create a significant uncertainty in disassembly tasks, namely, possibility of failed tasks. Such failures may lead to some successor tasks being infeasible, which changes work contents of downstream stations. To improve the profitability of such a disassembly lin...

  5. Multi-kanban mechanism for appliance disassembly

    Science.gov (United States)

    Udomsawat, Gun; Gupta, Surendra M.

    2005-11-01

    The use of household appliances continues to rise every year. A significant number of End-Of-Life (EOL) appliances are generated because of the introduction of newer models that are more attractive, efficient and affordable. Others are, of course, generated when they become non-functional. Many regulations encourage recycling of EOL appliances to reduce the amount of waste sent to landfills. In addition, EOL appliances offer the appliance manufacturing and remanufacturing industries a source of less expensive raw materials and components. For this reason product recovery has become a subject of interest during the past decade. In this paper, we study the disassembly line for appliance disassembly. We discuss and incorporate some of the complications that are inherent in disassembly line including product arrival, demand arrival, inventory fluctuation and production control mechanisms. We show how to overcome such complications by implementing a multi-kanban system in the appliance disassembly line setting. The multi-kanban system (MKS) relies on dynamic routing of kanbans according to the state of the system. We investigate the multi-kanban mechanism using simulation and explore the effect of product mix on performance of the traditional push system (TPS) and MKS in terms of controlling the system's inventory while attempting to achieve a decent customer service level.

  6. Assembly and disassembly of the nucleolus during the cell cycle.

    Science.gov (United States)

    Hernandez-Verdun, Danièle

    2011-01-01

    The nucleolus is a large nuclear domain in which transcription, maturation and assembly of ribosomes take place. In higher eukaryotes, nucleolar organization in three sub-domains reflects the compartmentation of the machineries related to active or inactive transcription of the ribosomal DNA, ribosomal RNA processing and assembly with ribosomal proteins of the two (40S and 60S) ribosomal subunits. The assembly of the nucleoli during telophase/early G(1) depends on pre-existing machineries inactivated during prophase (the transcription machinery and RNP processing complexes) and on partially processed 45S rRNAs inherited throughout mitosis. In telophase, the 45S rRNAs nucleate the prenucleolar bodies and order the dynamics of nucleolar assembly. The assembly/disassembly processes of the nucleolus depend on the equilibrium between phosphorylation/dephosphorylation of the transcription machinery and on the RNP processing complexes under the control of the CDK1-cyclin B kinase and PP1 phosphatases. The dynamics of assembly/disassembly of the nucleolus is time and space regulated.

  7. Disassembly and removal of sodium instrumentation test loop

    International Nuclear Information System (INIS)

    Ishikawa, Okinobu; Onojima, Takamitu; Nagai, Keiichi

    2000-07-01

    In 1999, the Sodium Instrumentation Test Loop was disassembled and removed. This report describes the tasks and experiences obtained in removing sodium from a storage tank, disassembling, and cleansing components and related activities. Overall the disassembly, handling and cleansing tasks proceeded as planned and the activities were carried out efficiently and safely. Documentation of the process is meant to establish not only a procedure, but also a guideline for future similar tasks. (author)

  8. Multikanban model for disassembly line with demand fluctuation

    Science.gov (United States)

    Udomsawat, Gun; Gupta, Surendra M.; Al-Turki, Yousef A. Y.

    2004-02-01

    In recent years, the continuous growth in consumer waste and dwindling natural resources has seriously threatened the environment. Realizing this, several countries have passed regulations that force manufacturers not only to manufacture environmentally conscious products, but also to take back their used products from consumers so that the components and materials recovered from the products may be reused and/or recycled. Disassembly plays an important role in product recovery. A disassembly line is perhaps the most suitable setting for disassembly of products in large quantities. Because a disassembly line has a tendency to generate excessive inventory, employing a kanban system can reduce the inventory level and let the system run more efficiently. A disassembly line is quite different from an assembly line. For example, not only can the demand arrive at the last station, it can also arrive at any of the other stations in the system. The demand for a component on the disassembly line could fluctuate widely. In fact, there are many other complicating matters that need to be considered to implement the concept of kanbans in such an environment. In this paper, we discuss the complications that are unique to a disassembly line. We discuss the complications in utilizing the conventional production control mechanisms in a disassembly line setting. We then show how to overcome them by implementing kanbans in a disassembly line setting with demand fluctuation and introduce the concept of multi-kanban mechanism. We demonstrate its effectiveness using a simulation model. An example is presented to illustrate the concept.

  9. Impact of different disassembly line balancing algorithms on the performance of dynamic kanban system for disassembly line

    Science.gov (United States)

    Kizilkaya, Elif A.; Gupta, Surendra M.

    2005-11-01

    In this paper, we compare the impact of different disassembly line balancing (DLB) algorithms on the performance of our recently introduced Dynamic Kanban System for Disassembly Line (DKSDL) to accommodate the vagaries of uncertainties associated with disassembly and remanufacturing processing. We consider a case study to illustrate the impact of various DLB algorithms on the DKSDL. The approach to the solution, scenario settings, results and the discussions of the results are included.

  10. Disassembling and modification of RA-3

    International Nuclear Information System (INIS)

    Tarizzo, R.D.

    1990-01-01

    The objective of this paper is to describe the partial disassembling and modification of RA-3, called the Modernization Project. It comprises all the technical and administrative steps directly related with this task. The improvement of RA-3 is a result of the lack of 90% enriched uranium obliging a change over to 20% enriched uranium. This brought about design modifications both in fuel elements and the reactor. The presentation of documents for the licensing authority as well as are detailed separately. The modernization project was divided in 25 tasks: 1) changing fuel element support table, 2) changing heat exchanger, 3) repairing of cooling towers, 4) repairing of primary circuit valves, 5) repairing of irradiation channels, 6) construction of a new sampler, 7) changing tangential channel, 8) cleaning and disassembling of reactor (inside), 9) changing continuous demineralizer (ion exchange column), 10) detection of failure in fuel elements, 11) modification of nuclear instrumentation, 12) modification of conventional instrumentation, 13) modification of electrical system, 14) changing telemanipulators, 15) construction of mechanism bridge, 16) changing a primary circuit valve when the heat exchanger is changed too, 17) painting ground floor, hall floor, and pump room floor with epoxy resin levelling, 18) installation of fire alarm system, 19) radioactive liquid discharge, 20) modification of secondary circuit (This task involves: a) installation of a third secondary pump, b) extension of this piping, c) installation of two 12 inch valves to the present cooling towers pools independent, d) installation of filtering system), 21) optimization hot water bed, 22) changing detector support table, 23) removal, decontamination and reinstallation of shielding, 25) changing pneumatic system

  11. Montmorillonite-induced Bacteriophage φ6 Disassembly

    Science.gov (United States)

    Trusiak, A.; Gottlieb, P.; Katz, A.; Alimova, A.; Steiner, J. C.; Block, K. A.

    2012-12-01

    It is estimated that there are 1031 virus particles on Earth making viruses an order of magnitude more prevalent in number than prokaryotes with the vast majority of viruses being bacteriophages. Clays are a major component of soils and aquatic sediments and can react with RNA, proteins and bacterial biofilms. The clays in soils serve as an important moderator between phage and their host bacteria, helping to preserve the evolutionary balance. Studies on the effects of clays on viral infectivity have given somewhat contradictory results; possibly a consequence of clay-virus interactions being dependent on the unique structure of particular viruses. In this work, the interaction between montmorillonite and the bacteriophage φ6 is investigated. φ6 is a member of the cystovirus family that infects Pseudomonas syringe, a common plant pathogen. As a member of the cystovirus family with an enveloped structure, φ6 serves as a model for reoviruses, a human pathogen. Experiments were conducted with φ6 suspended in dilute, purified homoionic commercial-grade montmorillonite over a range of virus:clay ratios. At a 1:100000 virus:clay ratio, the clay reduced viral infectivity by 99%. The minimum clay to virus ratio which results in a measurable reduction of P. syringae infection is 1:1. Electron microscopy demonstrates that mixed suspensions of smectite and virus co-aggregate to form flocs encompassing virions within the smectite. Both free viral particles as well as those imbedded in the flocs are seen in the micrographs to be missing the envelope- leaving only the nucleocapsid (NC) intact; indicating that smectite inactivates the virus by envelope disassembly. These results have strong implications in the evolution of both the φ6 virus and its P. syringae host cells. TEM of aggregate showing several disassembled NCs.

  12. Cleaning, disassembly, and requalification of the FFTF in vessel handling machine

    International Nuclear Information System (INIS)

    Coops, W.J.

    1977-10-01

    The Engineering Model In Vessel Handling Machine (IVHM) was successfully removed, cleaned, disassembled, inspected, reassembled and reinstalled into the sodium test vessel at Richland, Washington. This was the first time in the United States a full size operational sodium wetted machine has been cleaned by the water vapor nitrogen process and requalified for operation. The work utilized an atmospheric control system during removal, a tank type water vapor nitrogen cleaning system and an open ''hands on'' disassembly and assembly stand. Results of the work indicate the tools, process and equipment are adequate for the non-radioactive maintenance sequence. Additionally, the work proves that a machine of this complexity can be successfully cleaned, maintained and re-used without the need to replace a large percentage of the sodium wetted parts

  13. A Taxonomy and Comparison of Haptic Actions for Disassembly Tasks

    National Research Council Canada - National Science Library

    Bloomfield, Aaron; Deng, Yu; Wampler, Jeff; Rondot, Pascale; Harth, Dina; McManus, Mary; Badler, Norman

    2003-01-01

    .... We conducted a series of human subject experiments to compare user performance and preference on a disassembly task with and without haptic feedback using CyberGlove, Phantom, and SpaceMouse interfaces...

  14. Systems impacts of spent fuel disassembly alternatives

    International Nuclear Information System (INIS)

    1984-07-01

    Three studies were completed to evaluate four alternatives to the disposal of intact spent fuel assemblies in a geologic repository. A preferred spent fuel waste form for disposal was recommended on consideration of (1) package design and fuel/package interaction, (2) long-term, in-repository performance of the waste form, and (3) overall process performance and costs for packaging, handling, and emplacement. The four basic alternative waste forms considered were (1) end fitting removal, (2) fission gas venting, (3) disassembly and close packing, and (4) shearing/immobilization. None of the findings ruled out any alternative on the basis of waste package considerations or long-term performance of the waste form. The third alternative offers flexibility in loading that may prove attractive in the various geologic media under consideration, greatly reduces the number of packages, and has the lowest unit cost. These studies were completed in October, 1981. Since then Westinghouse Electric Corporation and the Office of Nuclear Waste Isolation have completed studies in related fields. This report is now being published to provide publicly the background material that is contained within. 47 references, 28 figures, 31 tables

  15. Artificial biofilms establish the role of matrix interactions in staphylococcal biofilm assembly and disassembly

    Science.gov (United States)

    Stewart, Elizabeth J.; Ganesan, Mahesh; Younger, John G.; Solomon, Michael J.

    2015-01-01

    We demonstrate that the microstructural and mechanical properties of bacterial biofilms can be created through colloidal self-assembly of cells and polymers, and thereby link the complex material properties of biofilms to well understood colloidal and polymeric behaviors. This finding is applied to soften and disassemble staphylococcal biofilms through pH changes. Bacterial biofilms are viscoelastic, structured communities of cells encapsulated in an extracellular polymeric substance (EPS) comprised of polysaccharides, proteins, and DNA. Although the identity and abundance of EPS macromolecules are known, how these matrix materials interact with themselves and bacterial cells to generate biofilm morphology and mechanics is not understood. Here, we find that the colloidal self-assembly of Staphylococcus epidermidis RP62A cells and polysaccharides into viscoelastic biofilms is driven by thermodynamic phase instability of EPS. pH conditions that induce phase instability of chitosan produce artificial S. epidermidis biofilms whose mechanics match natural S. epidermidis biofilms. Furthermore, pH-induced solubilization of the matrix triggers disassembly in both artificial and natural S. epidermidis biofilms. This pH-induced disassembly occurs in biofilms formed by five additional staphylococcal strains, including three clinical isolates. Our findings suggest that colloidal self-assembly of cells and matrix polymers produces biofilm viscoelasticity and that biofilm control strategies can exploit this mechanism. PMID:26272750

  16. Design-only conceptual design report for pit disassembly and conversion facility. Rev 0

    International Nuclear Information System (INIS)

    Zygmunt, S.; Christensen, L.; Richardson, C.

    1997-01-01

    This design-only conceptual design report (DOCDR) was prepared to support a funding request by the Department of Energy (DOE)-Office of Fissile Material Disposition (OFMD) for engineering design of the Pit Disassembly and Conversion Facility (PDCF) Project No. 99-D-141. The PDCF will be used to disassemble the nation's inventory of surplus nuclear weapons pits and convert the plutonium recovered from those pits into a form suitable for storage, international inspection, and final disposition. The PDCF is a complex consisting of a hardened building that will contain the plutonium processes in a safe and secure manner, and conventional buildings and structures that will house support personnel, systems, and equipment. The PDCF uses the Advanced Recovery and Integrated Extraction System (ARIES), a low waste, modular pyroprocessing system to convert pits to plutonium oxide. The PDCF project consists of engineering and design, and construction of the buildings and structures, and engineering and design, procurement, installation, testing and start-up of equipment to disassemble pits and convert plutonium in pits to oxide form. The facility is planned to operate for 10 years, averaging 3.5 metric tons (3.86 tons) of plutonium metal per year. On conclusion of operations, the PDCF will be decontaminated and decommissioned

  17. Design-only conceptual design report for pit disassembly and conversion facility. Rev 0

    Energy Technology Data Exchange (ETDEWEB)

    Zygmunt, S.; Christensen, L.; Richardson, C.

    1997-12-12

    This design-only conceptual design report (DOCDR) was prepared to support a funding request by the Department of Energy (DOE)-Office of Fissile Material Disposition (OFMD) for engineering design of the Pit Disassembly and Conversion Facility (PDCF) Project No. 99-D-141. The PDCF will be used to disassemble the nation`s inventory of surplus nuclear weapons pits and convert the plutonium recovered from those pits into a form suitable for storage, international inspection, and final disposition. The PDCF is a complex consisting of a hardened building that will contain the plutonium processes in a safe and secure manner, and conventional buildings and structures that will house support personnel, systems, and equipment. The PDCF uses the Advanced Recovery and Integrated Extraction System (ARIES), a low waste, modular pyroprocessing system to convert pits to plutonium oxide. The PDCF project consists of engineering and design, and construction of the buildings and structures, and engineering and design, procurement, installation, testing and start-up of equipment to disassemble pits and convert plutonium in pits to oxide form. The facility is planned to operate for 10 years, averaging 3.5 metric tons (3.86 tons) of plutonium metal per year. On conclusion of operations, the PDCF will be decontaminated and decommissioned.

  18. AGR-2 Irradiated Test Train Preliminary Inspection and Disassembly First Look

    Energy Technology Data Exchange (ETDEWEB)

    Ploger, Scott [Idaho National Lab. (INL), Idaho Falls, ID (United States); Demkowciz, Paul [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-05-01

    The AGR 2 irradiation experiment began in June 2010 and was completed in October 2013. The test train was shipped to the Materials and Fuels Complex in July 2014 for post-irradiation examination (PIE). The first PIE activities included nondestructive examination of the test train, followed by disassembly of the test train and individual capsules and detailed inspection of the capsule contents, including the fuel compacts and their graphite fuel holders. Dimensional metrology was then performed on the compacts, graphite holders, and steel capsule shells. AGR 2 disassembly and metrology were performed with the same equipment used successfully on AGR 1 test train components. Gamma spectrometry of the intact test train gave a preliminary look at the condition of the interior components. No evidence of damage to compacts or graphite components was evident from the isotopic and gross gamma scans. Disassembly of the AGR 2 test train and its capsules was conducted rapidly and efficiently by employing techniques refined during the AGR 1 disassembly campaign. Only one major difficulty was encountered while separating the test train into capsules when thermocouples (of larger diameter than used in AGR 1) and gas lines jammed inside the through tubes of the upper capsules, which required new tooling for extraction. Disassembly of individual capsules was straightforward with only a few minor complications. On the whole, AGR 2 capsule structural components appeared less embrittled than their AGR 1 counterparts. Compacts from AGR 2 Capsules 2, 3, 5, and 6 were in very good condition upon removal. Only relatively minor damage or markings were visible using high resolution photographic inspection. Compact dimensional measurements indicated radial shrinkage between 0.8 to 1.7%, with the greatest shrinkage observed on Capsule 2 compacts that were irradiated at higher temperature. Length shrinkage ranged from 0.1 to 0.9%, with by far the lowest axial shrinkage on Capsule 3 compacts

  19. Ufd1-Npl4 Recruit Cdc48 for Disassembly of Ubiquitylated CMG Helicase at the End of Chromosome Replication

    Directory of Open Access Journals (Sweden)

    Marija Maric

    2017-03-01

    Full Text Available Disassembly of the Cdc45-MCM-GINS (CMG DNA helicase is the key regulated step during DNA replication termination in eukaryotes, involving ubiquitylation of the Mcm7 helicase subunit, leading to a disassembly process that requires the Cdc48 “segregase”. Here, we employ a screen to identify partners of budding yeast Cdc48 that are important for disassembly of ubiquitylated CMG helicase at the end of chromosome replication. We demonstrate that the ubiquitin-binding Ufd1-Npl4 complex recruits Cdc48 to ubiquitylated CMG. Ubiquitylation of CMG in yeast cell extracts is dependent upon lysine 29 of Mcm7, which is the only detectable site of ubiquitylation both in vitro and in vivo (though in vivo other sites can be modified when K29 is mutated. Mutation of K29 abrogates in vitro recruitment of Ufd1-Npl4-Cdc48 to the CMG helicase, supporting a model whereby Ufd1-Npl4 recruits Cdc48 to ubiquitylated CMG at the end of chromosome replication, thereby driving the disassembly reaction.

  20. Disassembling and rebuilding 900 MW unit fuel assemblies in Celimene

    International Nuclear Information System (INIS)

    Giquel, G.; Leseur, A.; Pillet, C.; Van Craeynest, J.C.

    1987-01-01

    The Celimene high activity laboratory, in the Nuclear Research Centre of Saclay, has equipment for and experience of disassembling and rebuilding fuel assemblies from 900 MW light water reactors. These operations have been performed for R and D purposes; they allow removal for investigation of some of the fuel rods and examination of the skeleton. The rebuilt assemblies are sent to the fuel reprocessing plant. Reirradiation of these assemblies has not been considered so far and would require modifications of the procedure and of parts of the new skeleton. Disassembling and rebuilding have already been performed on three assemblies and a fourth one will be rebuilt in the coming months [fr

  1. Mathematical and Simulation Modelling of Moisture Diffusion Mechanism during Plastic IC Packages Disassembly

    OpenAIRE

    Peng Mou; Dong Xiang; Guanghong Duan

    2013-01-01

    Reuse of plastic IC packages disassembled from printed circuit boards (PCBs) has significant environmental benefits and economic value. The interface delamination caused by moisture diffusion is the main failure mode of IC packages during the disassembling process, which greatly reduces the reusability and reliability of disassembled IC packages. Exploring moisture diffusion mechanism is a prerequisite to optimize prebaking processes before disassembling that is an effective way to avoid the ...

  2. Desmosome Assembly and Disassembly Are Membrane Raft-Dependent

    Science.gov (United States)

    Faundez, Victor; Koval, Michael; Mattheyses, Alexa L.; Kowalczyk, Andrew P.

    2014-01-01

    Strong intercellular adhesion is critical for tissues that experience mechanical stress, such as the skin and heart. Desmosomes provide adhesive strength to tissues by anchoring desmosomal cadherins of neighboring cells to the intermediate filament cytoskeleton. Alterations in assembly and disassembly compromise desmosome function and may contribute to human diseases, such as the autoimmune skin blistering disease pemphigus vulgaris (PV). We previously demonstrated that PV auto-antibodies directed against the desmosomal cadherin desmoglein 3 (Dsg3) cause loss of adhesion by triggering membrane raft-mediated Dsg3 endocytosis. We hypothesized that raft membrane microdomains play a broader role in desmosome homeostasis by regulating the dynamics of desmosome assembly and disassembly. In human keratinocytes, Dsg3 is raft associated as determined by biochemical and super resolution immunofluorescence microscopy methods. Cholesterol depletion, which disrupts rafts, prevented desmosome assembly and adhesion, thus functionally linking rafts to desmosome formation. Interestingly, Dsg3 did not associate with rafts in cells lacking desmosomal proteins. Additionally, PV IgG-induced desmosome disassembly occurred by redistribution of Dsg3 into raft-containing endocytic membrane domains, resulting in cholesterol-dependent loss of adhesion. These findings demonstrate that membrane rafts are required for desmosome assembly and disassembly dynamics, suggesting therapeutic potential for raft targeting agents in desmosomal diseases such as PV. PMID:24498201

  3. Multi-kanban mechanism for personal computer disassembly

    Science.gov (United States)

    Udomsawat, Gun; Gupta, Surendra M.; Kamarthi, Sagar V.

    2004-12-01

    The use of personal computers (PCs) continues to increase every year. According to a 1999 figure, 50 percent of all US households owned PCs, a figure that continues to rise every year. With continuous development of sophisticated software, PCs are becoming increasingly powerful. In addition, the price of a PC continues to steadily decline. Furthermore, the typical life of a PC in the workplace is approximately two to three years while in the home it is three to five years. As these PCs become obsolete, they are replaced and the old PCs are disposed of. It is estimated that between 14 and 20 million PCs are retired annually in the US. While 20 to 30% of the units may be resold, the others are discarded. These discards represent a significant potential source of lead for the waste stream. In some communities, waste cathode ray tubes (CRTs) represent the second largest source of lead in the waste stream after vehicular lead acid batteries. PCs are, therefore, not suitable for dumping in landfills. Besides, several components of a PC can be reused and then there are other valuable materials that can also be harvested. And with the advent of product stewardship, product recovery is the best solution for manufacturers. Disassembly line is perhaps the most suitable set up for disassembling PCs. However, planning and scheduling of disassembly on a disassembly line is complicated. In this paper, we discuss some of the complications including product arrival, demand arrival, inventory fluctuation and production control mechanisms. We then show how to overcome them by implementing a multi-kanban mechanism in the PC disassembly line setting. The multi-kanban mechanism relies on dynamic routing of kanbans according to the state of the system. We investigate the multi-kanban mechanism using simulation and demonstrate that this mechanism is superior to the traditional push system in terms of controlling the system"s inventory while maintaining a decent customer service level.

  4. 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

  5. Actin-interacting Protein 1 Promotes Disassembly of Actin-depolymerizing Factor/Cofilin-bound Actin Filaments in a pH-dependent Manner.

    Science.gov (United States)

    Nomura, Kazumi; Hayakawa, Kimihide; Tatsumi, Hitoshi; Ono, Shoichiro

    2016-03-04

    Actin-interacting protein 1 (AIP1) is a conserved WD repeat protein that promotes disassembly of actin filaments when actin-depolymerizing factor (ADF)/cofilin is present. Although AIP1 is known to be essential for a number of cellular events involving dynamic rearrangement of the actin cytoskeleton, the regulatory mechanism of the function of AIP1 is unknown. In this study, we report that two AIP1 isoforms from the nematode Caenorhabditis elegans, known as UNC-78 and AIPL-1, are pH-sensitive in enhancement of actin filament disassembly. Both AIP1 isoforms only weakly enhance disassembly of ADF/cofilin-bound actin filaments at an acidic pH but show stronger disassembly activity at neutral and basic pH values. However, a severing-defective mutant of UNC-78 shows pH-insensitive binding to ADF/cofilin-decorated actin filaments, suggesting that the process of filament severing or disassembly, but not filament binding, is pH-dependent. His-60 of AIP1 is located near the predicted binding surface for the ADF/cofilin-actin complex, and an H60K mutation of AIP1 partially impairs its pH sensitivity, suggesting that His-60 is involved in the pH sensor for AIP1. These biochemical results suggest that pH-dependent changes in AIP1 activity might be a novel regulatory mechanism of actin filament dynamics. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Preliminary topical report on comparison reactor disassembly calculations

    International Nuclear Information System (INIS)

    McLaughlin, T.P.

    1975-11-01

    Preliminary results of comparison disassembly calculations for a representative LMFBR model (2100-l voided core) and arbitrary accident conditions are described. The analytical methods employed were the computer programs: FX2-POOL, PAD, and VENUS-II. The calculated fission energy depositions are in good agreement, as are measures of the destructive potential of the excursions, kinetic energy, and work. However, in some cases the resulting fuel temperatures are substantially divergent. Differences in the fission energy deposition appear to be attributable to residual inconsistencies in specifying the comparison cases. In contrast, temperature discrepancies probably stem from basic differences in the energy partition models inherent in the codes. Although explanations of the discrepancies are being pursued, the preliminary results indicate that all three computational methods provide a consistent, global characterization of the contrived disassembly accident

  7. Integrating Safeguards into the Pit Disassembly and Conversion Facility

    International Nuclear Information System (INIS)

    Clark, T.G.

    2002-01-01

    In September 2000, the United States and the Russian Federation entered into an agreement which stipulates each country will irreversibly transform 34 metric tons of weapons-grade plutonium into material which could not be used for weapon purposes. Supporting the Department of Energy's (DOE) program to dispose of excess nuclear materials, the Pit Disassembly and Conversion Facility (PDCF) is being designed and constructed to disassemble the weapon ''pits'' and convert the nuclear material to an oxide form for fabrication into reactor fuel at the separate Mixed Oxide Fuel Fabrication Facility. The PDCF design incorporates automation to the maximum extent possible to facilitate material safeguards, reduce worker dose, and improve processing efficiency. This includes provisions for automated guided vehicle movements for shipping containers, material transport via automated conveyor between processes, remote process control monitoring, and automated Nondestructive Assay product systems

  8. Capillarity-induced disassembly of virions in carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Fan Xiaobin; Peng Wenchao; Li Yang; Li Xianyu; Zhang Guoliang; Zhang Fengbao [School of Chemical Engineering and Technology, Tianjin University, Tianjin (China); Barclay, J Elaine; Evans, David J [Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH (United Kingdom)], E-mail: fbzhang@tju.edu.cn

    2008-04-23

    Studying the transport and fate of viruses through nanochannels is of great importance. By using the nanochannel of a carbon nanotube (CNT) as an ideal model, we evaluated the possibility of capillarity-induced viral transport through a closely fitting nanochannel and explored the mechanisms involved. It is shown both experimentally and theoretically that Cowpea mosaic virus can enter CNTs by capillarity. However, when introduced into a nanotube the protein capsid may disassemble. During the initial capillary filling stage, anomalous needle-shaped high pressure exists in the centre of the nanotube's entrance. This high pressure, combining with the significant negative pressure within the nanotube, may account for the disassembly of the virions.

  9. Status of the pit disassembly and conversion facility

    International Nuclear Information System (INIS)

    Wood, Warren T.; Christensen, Lowell T.

    2000-01-01

    A planned new facility, the Pit Disassembly and Conversion Facility (PDCF), will be used to disassemble the nation's inventory of surplus nuclear weapons pits and convert the plutonium from those pits into a form suitable for storage, international inspection, and final disposition. Sized to handle 35 metric tons of plutonium from pits and other sources over its 10-year operating life, the PDCF will apply the Advanced Recovery and Integrated Extraction System (ARIES) technology. ARIES process technology has been developed at Los Alamos National Laboratory (LANL) and Lawrence Livermore National Laboratory (LLNL), and an integrated system is being demonstrated at LANL. The Los Alamos National Laboratory is the lead for technical design oversight of the PDCF. Technical data gained from the ARIES demonstrations is integral for the proper design of the PDCF

  10. On the optimal design of the disassembly and recovery processes.

    Science.gov (United States)

    Xanthopoulos, A; Iakovou, E

    2009-05-01

    This paper tackles the problem of the optimal design of the recovery processes of the end-of-life (EOL) electric and electronic products, with a special focus on the disassembly issues. The objective is to recover as much ecological and economic value as possible, and to reduce the overall produced quantities of waste. In this context, a medium-range tactical problem is defined and a novel two-phased algorithm is presented for a remanufacturing-driven reverse supply chain. In the first phase, we propose a multicriteria/goal-programming analysis for the identification and the optimal selection of the most 'desirable' subassemblies and components to be disassembled for recovery, from a set of different types of EOL products. In the second phase, a multi-product, multi-period mixed-integer linear programming (MILP) model is presented, which addresses the optimization of the recovery processes, while taking into account explicitly the lead times of the disassembly and recovery processes. Moreover, a simulation-based solution approach is proposed for capturing the uncertainties in reverse logistics. The overall approach leads to an easy-to-use methodology that could support effectively middle level management decisions. Finally, the applicability of the developed methodology is illustrated by its application on a specific case study.

  11. On the optimal design of the disassembly and recovery processes

    International Nuclear Information System (INIS)

    Xanthopoulos, A.; Iakovou, E.

    2009-01-01

    This paper tackles the problem of the optimal design of the recovery processes of the end-of-life (EOL) electric and electronic products, with a special focus on the disassembly issues. The objective is to recover as much ecological and economic value as possible, and to reduce the overall produced quantities of waste. In this context, a medium-range tactical problem is defined and a novel two-phased algorithm is presented for a remanufacturing-driven reverse supply chain. In the first phase, we propose a multicriteria/goal-programming analysis for the identification and the optimal selection of the most 'desirable' subassemblies and components to be disassembled for recovery, from a set of different types of EOL products. In the second phase, a multi-product, multi-period mixed-integer linear programming (MILP) model is presented, which addresses the optimization of the recovery processes, while taking into account explicitly the lead times of the disassembly and recovery processes. Moreover, a simulation-based solution approach is proposed for capturing the uncertainties in reverse logistics. The overall approach leads to an easy-to-use methodology that could support effectively middle level management decisions. Finally, the applicability of the developed methodology is illustrated by its application on a specific case study

  12. Asymmetric ring structure of Vps4 required for ESCRT-III disassembly

    Science.gov (United States)

    Caillat, Christophe; Macheboeuf, Pauline; Wu, Yuanfei; McCarthy, Andrew A.; Boeri-Erba, Elisabetta; Effantin, Gregory; Göttlinger, Heinrich G.; Weissenhorn, Winfried; Renesto, Patricia

    2015-12-01

    The vacuolar protein sorting 4 AAA-ATPase (Vps4) recycles endosomal sorting complexes required for transport (ESCRT-III) polymers from cellular membranes. Here we present a 3.6-Å X-ray structure of ring-shaped Vps4 from Metallosphera sedula (MsVps4), seen as an asymmetric pseudohexamer. Conserved key interface residues are shown to be important for MsVps4 assembly, ATPase activity in vitro, ESCRT-III disassembly in vitro and HIV-1 budding. ADP binding leads to conformational changes within the protomer, which might propagate within the ring structure. All ATP-binding sites are accessible and the pseudohexamer binds six ATP with micromolar affinity in vitro. In contrast, ADP occupies one high-affinity and five low-affinity binding sites in vitro, consistent with conformational asymmetry induced on ATP hydrolysis. The structure represents a snapshot of an assembled Vps4 conformation and provides insight into the molecular motions the ring structure undergoes in a concerted action to couple ATP hydrolysis to ESCRT-III substrate disassembly.

  13. SAVANNAH RIVER SITE R REACTOR DISASSEMBLY BASIN IN SITU DECOMMISSIONING

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Blankenship, J.; Griffin, W.; Serrato, M.

    2009-12-03

    The US DOE concept for facility in-situ decommissioning (ISD) is to physically stabilize and isolate in tact, structurally sound facilities that are no longer needed for their original purpose of, i.e., generating (reactor facilities), processing(isotope separation facilities) or storing radioactive materials. The 105-R Disassembly Basin is the first SRS reactor facility to undergo the in-situ decommissioning (ISD) process. This ISD process complies with the105-R Disassembly Basin project strategy as outlined in the Engineering Evaluation/Cost Analysis for the Grouting of the R-Reactor Disassembly Basin at the Savannah River Site and includes: (1) Managing residual water by solidification in-place or evaporation at another facility; (2) Filling the below grade portion of the basin with cementitious materials to physically stabilize the basin and prevent collapse of the final cap - Sludge and debris in the bottom few feet of the basin will be encapsulated between the basin floor and overlying fill material to isolate if from the environment; (3) Demolishing the above grade portion of the structure and relocating the resulting debris to another location or disposing of the debris in-place; and (4) Capping the basin area with a concrete slab which is part of an engineered cap to prevent inadvertent intrusion. The estimated total grout volume to fill the 105-R Reactor Disassembly Basin is 24,424 cubic meters or 31,945 cubic yards. Portland cement-based structural fill materials were design and tested for the reactor ISD project and a placement strategy for stabilizing the basin was developed. Based on structural engineering analyses and work flow considerations, the recommended maximum lift height is 5 feet with 24 hours between lifts. Pertinent data and information related to the SRS 105-R-Reactor Disassembly Basin in-situ decommissioning include: regulatory documentation, residual water management, area preparation activities, technology needs, fill material designs

  14. Disassembly of JT-60 tokamak device and ancillary facilities for JT-60 tokamak

    International Nuclear Information System (INIS)

    Okano, Fuminori; Ichige, Hisashi; Miyo, Yasuhiko; Kaminaga, Atsushi; Sasajima, Tadayuki; Nishiyama, Tomokazu; Yagyu, Jun-ichi; Ishige, Youichi; Suzuki, Hiroaki; Komuro, Kenichi; Sakasai, Akira; Ikeda, Yoshitaka

    2014-03-01

    The disassembly of JT-60 tokamak device and its peripheral equipments, where the total weight was about 5400 tons, started in 2009 and accomplished in October 2012. This disassembly was required process for JT-60SA project, which is the Satellite Tokamak project under Japan-EU international corroboration to modify the JT-60 to the superconducting tokamak. This work was the first experience of disassembling a large radioactive fusion device based on Radiation Hazard Prevention Act in Japan. The cutting was one of the main problems in this disassembly, such as to cut the welded parts together with toroidal field coils, and to cut the vacuum vessel into two. After solving these problems, the disassembly completed without disaster and accident. This report presents the outline of the JT-60 disassembly, especially tokamak device and ancillary facilities for tokamak device. (author)

  15. Spent fuel disassembly and canning programs at the Barnwell Nuclear Fuel Plant (BNFP)

    International Nuclear Information System (INIS)

    Townes, G.A.

    1979-10-01

    Methods of disassembling and canning spent fuel to allow more efficient storage are being investigated at the BNFP. Studies and development programs are aimed at dry disassembly of fuel to allow storage and shipment of fuel pins rather than full fuel assemblies. Results indicate that doubling existing storage capacity or tripling the carrying capacity of existing transportation equipment is achievable. Disassembly could be performed in the BNFP hot cells at rates of about 12 to 15 assemblies per day

  16. Application of industrial robots in automatic disassembly line of waste LCD displays

    Science.gov (United States)

    Wang, Sujuan

    2017-11-01

    In the automatic disassembly line of waste LCD displays, LCD displays are disassembled into plastic shells, metal shields, circuit boards, and LCD panels. Two industrial robots are used to cut metal shields and remove circuit boards in this automatic disassembly line. The functions of these two industrial robots, and the solutions to the critical issues of model selection, the interfaces with PLCs and the workflows were described in detail in this paper.

  17. Corrosion of aluminum alloys in a reactor disassembly basin

    International Nuclear Information System (INIS)

    Howell, J.P.; Zapp, P.E.; Nelson, D.Z.

    1992-01-01

    This document discusses storage of aluminum clad fuel and target tubes of the Mark 22 assembly takes place in the concrete-lined, light-water-filled, disassembly basins located within each reactor area at the Savannah River Site (SRS). A corrosion test program has been conducted in the K-Reactor disassembly basin to assess the storage performance of the assemblies and other aluminum clad components in the current basin environment. Aluminum clad alloys cut from the ends of actual fuel and target tubes were originally placed in the disassembly water basin in December 1991. After time intervals varying from 45--182 days, the components were removed from the basin, photographed, and evaluated metallographically for corrosion performance. Results indicated that pitting of the 8001 aluminum fuel clad alloy exceeded the 30-mil (0.076 cm) cladding thickness within the 45-day exposure period. Pitting of the 1100 aluminum target clad alloy exceeded the 30-mil (0.076 cm) clad thickness in 107--182 days exposure. The existing basin water chemistry is within limits established during early site operations. Impurities such as Cl - , NO 3 - and SO 4 - are controlled to the parts per million level and basin water conductivity is currently 170--190 μmho/cm. The test program has demonstrated that the basin water is aggressive to the aluminum components at these levels. Other storage basins at SRS and around the US have successfully stored aluminum components for greater than ten years without pitting corrosion. These basins have impurity levels controlled to the parts per billion level (1000X lower) and conductivity less than 1.0 μmho/cm

  18. TRIM15 is a focal adhesion protein that regulates focal adhesion disassembly

    Science.gov (United States)

    Uchil, Pradeep D.; Pawliczek, Tobias; Reynolds, Tracy D.; Ding, Siyuan; Hinz, Angelika; Munro, James B.; Huang, Fang; Floyd, Robert W.; Yang, Haitao; Hamilton, William L.; Bewersdorf, Joerg; Xiong, Yong; Calderwood, David A.; Mothes, Walther

    2014-01-01

    ABSTRACT Focal adhesions are macromolecular complexes that connect the actin cytoskeleton to the extracellular matrix. Dynamic turnover of focal adhesions is crucial for cell migration. Paxillin is a multi-adaptor protein that plays an important role in regulating focal adhesion dynamics. Here, we identify TRIM15, a member of the tripartite motif protein family, as a paxillin-interacting factor and a component of focal adhesions. TRIM15 localizes to focal contacts in a myosin-II-independent manner by an interaction between its coiled-coil domain and the LD2 motif of paxillin. Unlike other focal adhesion proteins, TRIM15 is a stable focal adhesion component with restricted mobility due to its ability to form oligomers. TRIM15-depleted cells display impaired cell migration and reduced focal adhesion disassembly rates, in addition to enlarged focal adhesions. Thus, our studies demonstrate a cellular function for TRIM15 as a regulatory component of focal adhesion turnover and cell migration. PMID:25015296

  19. Phosphorylation and disassembly of intermediate filaments in mitotic cells

    International Nuclear Information System (INIS)

    Chou, Yinghao; Rosevear, E.; Goldman, R.D.

    1989-01-01

    As baby hamster kidney (BHK-21) cells enter mitosis, networks of intermediate filaments (IFs) are transformed into cytoplasmic aggregates of protofilaments. Coincident with this morphological change, the phosphate content of vimentin increases from 0.3 mol of P i per mol of protein in interphase to 1.9 mol of P i per mol of protein in mitosis. A similar increase in phosphate content is observed with desmin, from 0.5 mol of P i per mol of protein to 1.5 mol of P i per mol of protein. Fractionation of mitotic cell lysates by hydroxylapatite column chromatography reveals the presence of two IF protein kinase activities, designated as IF protein kinase I and IF protein kinase II. Comparison of two-dimensional 32 P-labeled phosphopeptide maps of vimentin and desmin phosphorylated in vivo in mitosis, and in vitro using partially purified kinase fractions, reveals extensive similarity in the two sets of phosphorylation sites. Phosphorylation of in vitro polymerized IFs by IF protein kinase II induces complete disassembly as determined by negative-stain electron microscopy. The results support the idea that the disassembly of IFs in mitosis is regulated by the phosphorylation of its subunit proteins

  20. Digital mock-up for the spent fuel disassembly processes

    International Nuclear Information System (INIS)

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

    2000-12-01

    In this study, the graphical design system is developed and the digital mock-up is implemented for designing the spent fuel handling and disassembly processes. The system consists of a 3D graphical modeling system, a devices assembling system, and a motion simulation system. This system is used throughout the design stages from the conceptual design to the motion analysis. By using this system, all the process involved in the spent fuel handling and disassembly processes are analyzed and optimized. Also, this system is used in developing the on-line graphic simulator which synchronously simulates the motion of the equipment in a real time basis by connecting the device controllers with the graphic server through the TCP/IP network. This simulator can be effectively used for detecting the malfunctions of the process equipment which is remotely operated. Thus, the simulator enhances the reliability and safety of the spent fuel handling process by providing the remote monitoring function of the process. The graphical design system and the digital mock-up system can be effectively used for designing the process equipment, as well as the optimized process and maintenance process. And the on-line graphic simulator can be an alternative of the conventional process monitoring system which is a hardware based system

  1. ARIES pit disassembly-safeguards issues for transparency

    International Nuclear Information System (INIS)

    Fearey, B.L.; Cremers, T.L.

    1995-01-01

    Historic changes are now occurring in U.S. nonproliferation and arms control policy. The quantity of nuclear weapons required to provide a deterrence has decreased (especially with the end of the Cold War). Further, various bilateral and multilateral treaties now require the removal of numerous nuclear weapons from the U.S. stockpile. Although the removal of such weapons appears straightforward, the final disposition of the surplus weapons-grade nuclear material must be carefully considered. Domestically, several plutonium disposition plans are now under consideration concerning long-term safety, materials accounting, environmental impact, accessibility, and long-term containment. The Automated Retirement and Integrated Extraction System (ARIES) currently under development at Los Alamos National Laboratory is one such disposition method for the disassembly of plutonium weapons components (pits). The ARIES system integrates and automates several features: disassembly of pits, consolidation of the plutonium material, on-line measurement of final products, waste streams, and long-term packaging. Clearly, in any plutonium disposition plan, the safeguards aspects of materials control and accounting and the security aspects must be carefully considered and evaluated

  2. Polygons and adhesion plaques and the disassembly and assembly of myofibrils in cardiac myocytes.

    Science.gov (United States)

    Lin, Z X; Holtzer, S; Schultheiss, T; Murray, J; Masaki, T; Fischman, D A; Holtzer, H

    1989-06-01

    Successive stages in the disassembly of myofibrils and the subsequent assembly of new myofibrils have been studied in cultures of dissociated chick cardiac myocytes. The myofibrils in trypsinized and dispersed myocytes are sequentially disassembled during the first 3 d of culture. They split longitudinally and then assemble into transitory polygons. Multiples of single sarcomeres, the cardiac polygons, are analogous to the transitory polygonal configurations assumed by stress fibers in spreading fibroblasts. They differ from their counterparts in fibroblasts in that they consist of muscle alpha-actinin vertices and muscle myosin heavy chain struts, rather than of the nonmuscle contractile protein isoforms of stress fiber polygons. EM sections reveal the vertices and struts in cardiac polygons to be typical Z and A bands. Most cardiac polygons are eliminated by day 5 of culture. Concurrent with the disassembly and elimination of the original myofibrils new myofibrils are rapidly assembled elsewhere in the same myocyte. Without exception both distal tips of each nascent myofibril terminate in adhesion plaques. The morphology and composition of the adhesion plaques capping each end of each myofibril are similar to those of the termini of stress fibers in fibroblasts. However, whereas the adhesion complexes involving stress fibers in fibroblasts consist of vinculin/nonmuscle alpha-actinin/beta- and gamma-actins, the analogous structures in myocytes involving myofibrils consist of vinculin/muscle alpha-actinin/alpha-actin. The addition of 1.7-2.0 microns sarcomeres to the distal tips of an elongating myofibril, irrespective of whether the myofibril consists of 1, 10, or several hundred tandem sarcomeres, occurs while the myofibril appears to remain linked to its respective adhesion plaques. The adhesion plaques in vitro are the equivalent of the in vivo intercalated discs, both in terms of their molecular composition and with respect to their functioning as initiating

  3. Movement and equipositioning of plasmids by ParA filament disassembly

    DEFF Research Database (Denmark)

    Ringgaard, Simon; van Zon, Jeroen; Howard, Martin

    2009-01-01

    , plasmids consistently migrate behind disassembling ParA cytoskeletal structures, suggesting that ParA filaments pull plasmids by depolymerization. The perpetual cycles of ParA assembly and disassembly result in continuous relocation of plasmids, which, on time averaging, results in equidistribution...

  4. Coordination of substrate binding and ATP hydrolysis in Vps4-mediated ESCRT-III disassembly.

    Science.gov (United States)

    Davies, Brian A; Azmi, Ishara F; Payne, Johanna; Shestakova, Anna; Horazdovsky, Bruce F; Babst, Markus; Katzmann, David J

    2010-10-01

    ESCRT-III undergoes dynamic assembly and disassembly to facilitate membrane exvagination processes including multivesicular body (MVB) formation, enveloped virus budding, and membrane abscission during cytokinesis. The AAA-ATPase Vps4 is required for ESCRT-III disassembly, however the coordination of Vps4 ATP hydrolysis with ESCRT-III binding and disassembly is not understood. Vps4 ATP hydrolysis has been proposed to execute ESCRT-III disassembly as either a stable oligomer or an unstable oligomer whose dissociation drives ESCRT-III disassembly. An in vitro ESCRT-III disassembly assay was developed to analyze Vps4 function during this process. The studies presented here support a model in which Vps4 acts as a stable oligomer during ATP hydrolysis and ESCRT-III disassembly. Moreover, Vps4 oligomer binding to ESCRT-III induces coordination of ATP hydrolysis at the level of individual Vps4 subunits. These results suggest that Vps4 functions as a stable oligomer that acts upon individual ESCRT-III subunits to facilitate ESCRT-III disassembly.

  5. Disassembly for remanufacturing: A systematic literature review, new model development and future research needs

    Directory of Open Access Journals (Sweden)

    Anjar Priyono

    2016-11-01

    Full Text Available Purpose: Disassembly is an important process that distinguishes remanufacturing from conventional manufacturing. It is a unique process that becomes focus of investigation from many scholars. Yet, most scholars investigate disassembly from technical and operational standpoint that lack of strategic perspective. This paper attempts to fill this gap by looking at disassembly from a strategic perspective by considering organisational characteristics, process choices and product attributes. To be more specific, this paper has three objectives. First, to gain understanding what has been done, and what need to be done in the field of disassembly in remanufacturing. Second, to conduct a systematic literature review for identifying the factors affecting disassembly for remanufacturing. Third, to propose a new model of disassembly for remanufacturing and also to provide avenues for future research. Design/methodology/approach: This study used a systematic literature review method. A series of steps were undertaken during the review. The study was started with determining the purpose of the study, selecting appropriate keywords, and reducing the selected papers using a number of criteria. A deeper analysis was carried out on the final paper that meets the criteria for this review. Findings: There are two main findings of this study. First, a list of factors affecting disassembly in remanufacturing is identified. The factors can be categorised into three groups: organisational factors, process choices and product attributes. Second, using factors that have been identified, a new model of disassembly process for remanufacturing is developed. Current studies only consider disassembly as a physical activity to break down products into components. In the new model, disassembly is viewed as a process that converts into into output, which consist of a series of steps. Research limitations/implications: The opportunities for future research include: the need to

  6. Disassembly for remanufacturing: A systematic literature review, new model development and future research needs

    International Nuclear Information System (INIS)

    Priyono, A.; Ijomah, W.; Bititci, U.

    2016-01-01

    Purpose: Disassembly is an important process that distinguishes remanufacturing from conventional manufacturing. It is a unique process that becomes focus of investigation from many scholars. Yet, most scholars investigate disassembly from technical and operational standpoint that lack of strategic perspective. This paper attempts to fill this gap by looking at disassembly from a strategic perspective by considering organisational characteristics, process choices and product attributes. To be more specific, this paper has three objectives. First, to gain understanding what has been done, and what need to be done in the field of disassembly in remanufacturing. Second, to conduct a systematic literature review for identifying the factors affecting disassembly for remanufacturing. Third, to propose a new model of disassembly for remanufacturing and also to provide avenues for future research. Design/methodology/approach: This study used a systematic literature review method. A series of steps were undertaken during the review. The study was started with determining the purpose of the study, selecting appropriate keywords, and reducing the selected papers using a number of criteria. A deeper analysis was carried out on the final paper that meets the criteria for this review. Findings: There are two main findings of this study. First, a list of factors affecting disassembly in remanufacturing is identified. The factors can be categorised into three groups: organisational factors, process choices and product attributes. Second, using factors that have been identified, a new model of disassembly process for remanufacturing is developed. Current studies only consider disassembly as a physical activity to break down products into components. In the new model, disassembly is viewed as a process that converts into into output, which consist of a series of steps. Research limitations/implications: The opportunities for future research include: the need to develop an index of

  7. Disassembly for remanufacturing: A systematic literature review, new model development and future research needs

    Energy Technology Data Exchange (ETDEWEB)

    Priyono, A.; Ijomah, W.; Bititci, U.

    2016-07-01

    Purpose: Disassembly is an important process that distinguishes remanufacturing from conventional manufacturing. It is a unique process that becomes focus of investigation from many scholars. Yet, most scholars investigate disassembly from technical and operational standpoint that lack of strategic perspective. This paper attempts to fill this gap by looking at disassembly from a strategic perspective by considering organisational characteristics, process choices and product attributes. To be more specific, this paper has three objectives. First, to gain understanding what has been done, and what need to be done in the field of disassembly in remanufacturing. Second, to conduct a systematic literature review for identifying the factors affecting disassembly for remanufacturing. Third, to propose a new model of disassembly for remanufacturing and also to provide avenues for future research. Design/methodology/approach: This study used a systematic literature review method. A series of steps were undertaken during the review. The study was started with determining the purpose of the study, selecting appropriate keywords, and reducing the selected papers using a number of criteria. A deeper analysis was carried out on the final paper that meets the criteria for this review. Findings: There are two main findings of this study. First, a list of factors affecting disassembly in remanufacturing is identified. The factors can be categorised into three groups: organisational factors, process choices and product attributes. Second, using factors that have been identified, a new model of disassembly process for remanufacturing is developed. Current studies only consider disassembly as a physical activity to break down products into components. In the new model, disassembly is viewed as a process that converts into into output, which consist of a series of steps. Research limitations/implications: The opportunities for future research include: the need to develop an index of

  8. Innovation and employee injury risk in automotive disassembly operations

    DEFF Research Database (Denmark)

    Neumann, W. Patrick; Winkel, Jørgen; Palmerud, Gunnar

    2018-01-01

    to control injury hazards as part of the development and design process. These cases suggest how failure to manage RSI hazards in the innovation process may allow increases of injury risks that can compromise operational performance. This ‘innovation pitfall’ has implications for operator health...... increased movement speeds and reduced muscular recovery opportunities, implying increased RSI risk. This case study reveals a mechanism by which innovation may increase RSI risks for operators. Managers responsible for engineering innovation should ensure their teams have the tools and mandate necessary......Engineering innovations in car disassembly systems are studied for affects on system operators’ risk of repetitive strain injury (RSI). Objective instrumented measures of injury risk factors with synchronised video-based task analyses were used to examine changes in operators’ RSI risk during...

  9. Maintenance and disassembly considerations for the Technology Demonstration Facility

    International Nuclear Information System (INIS)

    Spampinato, P.T.

    1983-01-01

    The Technology Demonstration Facility (TDF) is a tandem-mirror design concept carried out under the direction of Lawrence Livermore National Laboratory. It was conceived as a near-term device with a mission of developing engineering technology in a D-T fusion environment. Overall maintenance and component disassembly were among the responsibilities of the Fusion Engineering Design Center (FEDC). A configuration evolved that was based on the operational requirements of the components, as well as the requirements for their replacements. Component lifetime estimates were used to estimate the frequency and the number of replacements. In addition, it was determined that the need for remote handling equipment followed within 1.5 years after initial start-up, emphasizing the direct relationship between developing maintenance scenarios/equipment and the device configuration. Many of the scheduled maintenance operations were investigated to first order, and preliminary handling equipment concepts were developed

  10. Introductory Education for Mechanical Engineering by Exercise in Mechanical Disassembly

    Science.gov (United States)

    Matsui, Yoshio; Asakawa, Naoki; Iwamori, Satoru

    An introductory program “Exercise for engineers in mechanical disassembly” is an exercise that ten students of every team disassemble a motor scooter to the components and then assemble again to the initial form in 15 weeks. The purpose of this program is to introduce mechanical engineering by touching the real machine and learning how it is composed from various mechanical parts to the students at the early period after the entrance into the university. Additional short lectures by young teachers and a special lecture by a top engineer in the industry encourage the students to combine the actual machine and the mechanical engineering subjects. Furthermore, various educations such as group leader system, hazard prediction training, parts filing are included in this program. As a result, students recognize the importance of the mechanical engineering study and the way of group working.

  11. Knowledge of damage identification about tensegrities via flexibility disassembly

    Science.gov (United States)

    Jiang, Ge; Feng, Xiaodong; Du, Shigui

    2017-12-01

    Tensegrity structures composing of continuous cables and discrete struts are under tension and compression, respectively. In order to determine the damage extents of tensegrity structures, a new method for tensegrity structural damage identification is presented based on flexibility disassembly. To decompose a tensegrity structural flexibility matrix into the matrix represention of the connectivity between degress-of-freedoms and the diagonal matrix comprising of magnitude informations. Step 1: Calculate perturbation flexibility; Step 2: Compute the flexibility connectivity matrix and perturbation flexibility parameters; Step 3: Calculate the perturbation stiffness parameters. The efficiency of the proposed method is demonstrated by a numeical example comprising of 12 cables and 4 struts with pretensioned. Accurate identification of local damage depends on the availability of good measured data, an accurate and reasonable algorithm.

  12. Workshop on instrumentation of the disassembled BER II

    International Nuclear Information System (INIS)

    Jauch, W.; Steiner, M.

    1982-01-01

    A workshop on the instrumentation of a disassembled BER II-reactor took place in the Hahn-Meitner-Institute in Berlin on April 19 and 20, 1982. Invited were all groups that are promoted by the associations 'Neutron Scattering for Investigation of Condensed Substance' and 'Neutron Scattering and Complementary Methods in Chemistry and Biology', along with experts for neutron spectrometers. 40 foreign scientists from 22 different institutes had accepted the invitation. The actual questions were treated in 13 presentations and a certain number of posters, with the latter also comprising activation analysis. The present report contains the presentations submitted, the final discussion minutes and a summary from HMI-view. (orig./RW) [de

  13. A reactor vessel and its internals disassembled and packaged

    International Nuclear Information System (INIS)

    Eisenmann, B.; Prechtl, E.; Suessdorf, W.

    2008-01-01

    2007 was a successful year for the Disassembly Unit of the Karlsruhe Research Center: dismantling the highly activated Karlsruhe Multipurpose Research Reactor (MZFR) was completed successfully and without any incident. A vote of thanks is expressed at this point to all staff members, participating industries and institutions for their extraordinary commitment and their outstanding innovation and work. Preserving and advancing existing knowledge is one of the important pillars securing a sustainable future for generations to come in Germany. Securing and advancing know-how in nuclear technology was defined as a major duty last in late January 2008 by Dr. Peter Fritz, Chairman of the Kerntechnische Gesellschaft e.V. (KTG) and member of the Executive Board of the Karlsruhe Research Center, for instance, in cooperation between the KERNTECHNIK (i.e. nuclear technology) Southwestern Research and Teaching Association and the Karlsruhe Institute of Technology (KIT). The borders of Germany do not constitute a natural radiological barrier, despite the efforts by political groups in this country to convey this impression. This report therefore is to document that the demolition of a nuclear reactor with a high radioactivity inventory can be managed safely. In the light of the experience accumulated with the MZFR, this is feasible only if demolition is carried out immediately instead of the 'problem' of disassembly and conditioning being shifted to future generations. The article is also meant to be a piece of advice by showing the unplannable difficulties which came up, and the technical solutions implemented by the competence team successfully and efficiently. (orig.)

  14. Sequential phosphorylation of GRASP65 during mitotic Golgi disassembly

    Directory of Open Access Journals (Sweden)

    Danming Tang

    2012-09-01

    GRASP65 phosphorylation during mitosis and dephosphorylation after mitosis are required for Golgi disassembly and reassembly during the cell cycle. At least eight phosphorylation sites on GRASP65 have been identified, but whether they are modified in a coordinated fashion during mitosis is so far unknown. In this study, we raised phospho-specific antibodies that recognize phosphorylated T220/T224, S277 and S376 residues of GRASP65, respectively. Biochemical analysis showed that cdc2 phosphorylates all three sites, while plk1 enhances the phosphorylation. Microscopic studies using these antibodies for double and triple labeling demonstrate sequential phosphorylation and dephosphorylation during the cell cycle. S277 and S376 are phosphorylated from late G2 phase through metaphase until telophase when the new Golgi is reassembled. T220/224 is not modified until prophase, but is highly modified from prometaphase to anaphase. In metaphase, phospho-T220/224 signal localizes on both Golgi haze and mitotic Golgi clusters that represent dispersed Golgi vesicles and Golgi remnants, respectively, while phospho-S277 and S376 labeling is more concentrated on mitotic Golgi clusters. Expression of a phosphorylation-resistant GRASP65 mutant T220A/T224A inhibited mitotic Golgi fragmentation to a much larger extent than the expression of the S277A and S376A mutants. In cytokinesis, T220/224 dephosphorylation occurs prior to that of S277, but after S376. This study provides evidence that GRASP65 is sequentially phosphorylated and dephosphorylated during mitosis at different sites to orchestrate Golgi disassembly and reassembly during cell division, with phosphorylation of the T220/224 site being most critical in the process.

  15. Development of remote disassembly technology for liquid-metal reactor (LMR) fuel

    International Nuclear Information System (INIS)

    Bradley, E.C.; Evans, J.H.; Metz, C.F. III; Weil, B.S.

    1990-01-01

    A major objective of the Consolidated Fuel Reprocessing Program (CFRP) is to develop equipment and demonstrate technology to reprocess fast breeder reactor fuel. Experimental work on fuel disassembly cutting methods began in the 1970s. High-power laser cutting was selected as the preferred cutting method for fuel disassembly. Remotely operated development equipment was designed, fabricated, installed, and tested at Oak Ridge National Laboratory (ORNL). Development testing included remote automatic operation, remote maintenance testing, and laser cutting process development. This paper summarizes the development work performed at ORNL on remote fuel disassembly. 2 refs., 1 fig

  16. Balancing Disassembly Line in Product Recovery to Promote the Coordinated Development of Economy and Environment

    Directory of Open Access Journals (Sweden)

    Jia Liu

    2017-02-01

    Full Text Available For environmentally conscious and sustainable manufacturing, many more manufacturers are acting to recycle and remanufacture their post-consumed products. The most critical process of remanufacturing is disassembly, since it allows for the selective extraction of the valuable components and materials from returned products to reduce the waste disposal volume. It is, therefore, important to design and balance the disassembly line to work efficiently due to its vital role in effective resource usage and environmental protection. Considering the disassembly precedence relationships and sequence-dependent parts removal time increments, this paper presents an improved discrete artificial bee colony algorithm (DABC for solving the sequence-dependent disassembly line balancing problem (SDDLBP. The performance of the proposed algorithm was tested against nine other approaches. Computational results evidently indicate the superior efficiency of the proposed algorithm for addressing the environmental and economic concerns while optimizing the multi-objective SDDLBP.

  17. Disassembly Properties of Cementitious Finish Joints Using an Induction Heating Method

    Science.gov (United States)

    Ahn, Jaecheol; Noguchi, Takafumi; Kitagaki, Ryoma

    2015-01-01

    Efficient maintenance and upgrading of a building during its lifecycle are difficult because a cementitious finish uses materials and parts with low disassembly properties. Additionally, the reuse and recycling processes during building demolition also present numerous problems from the perspective of environmental technology. In this study, an induction heating (IH) method was used to disassemble cementitious finish joints, which are widely used to join building members and materials. The IH rapidly and selectively heated and weakened these joints. The temperature elevation characteristics of the cementitious joint materials were measured as a function of several resistor types, including wire meshes and punching metals, which are usually used for cementitious finishing. The disassembly properties were evaluated through various tests using conductive resistors in cementitious joints such as mortar. When steel fiber, punching metal, and wire mesh were used as conductive resistors, the cementitious modifiers could be weakened within 30 s. Cementitious joints with conductive resistors also showed complete disassembly with little residual bond strength.

  18. Direct measurement of conformational strain energy in protofilaments curling outward from disassembling microtubule tips.

    Science.gov (United States)

    Driver, Jonathan W; Geyer, Elisabeth A; Bailey, Megan E; Rice, Luke M; Asbury, Charles L

    2017-06-19

    Disassembling microtubules can generate movement independently of motor enzymes, especially at kinetochores where they drive chromosome motility. A popular explanation is the 'conformational wave' model, in which protofilaments pull on the kinetochore as they curl outward from a disassembling tip. But whether protofilaments can work efficiently via this spring-like mechanism has been unclear. By modifying a previous assay to use recombinant tubulin and feedback-controlled laser trapping, we directly demonstrate the spring-like elasticity of curling protofilaments. Measuring their mechanical work output suggests they carry ~25% of the energy of GTP hydrolysis as bending strain, enabling them to drive movement with efficiency similar to conventional motors. Surprisingly, a β-tubulin mutant that dramatically slows disassembly has no effect on work output, indicating an uncoupling of disassembly speed from protofilament strain. These results show the wave mechanism can make a major contribution to kinetochore motility and establish a direct approach for measuring tubulin mechano-chemistry.

  19. Decommissioning of nuclear facilities: Decontamination, disassembly and waste management

    International Nuclear Information System (INIS)

    1983-01-01

    The term 'decommissioning', as used within the nuclear industry, means the actions taken at the end of a facility's useful life to retire the facility from service in a manner that provides adequate protection for the health and safety of the decommissioning workers, the general public, and for the environment. These actions can range from merely closing down the facility and a minimal removal of radioactive material coupled with continuing maintenance and surveillance, to a complete removal of residual radioactivity in excess of levels acceptable for unrestricted use of the facility and its site. This latter condition, unrestricted use, is the ultimate goal of all decommissioning actions at retired nuclear facilities. The purpose of this report is to provide an information base on the considerations important to decommissioning, the methods available for decontamination and disassembly of a nuclear facility, the management of the resulting radioactive wastes, and the areas of decommissioning methodology where improvements might be made. Specific sections are devoted to each of these topics, and conclusions are presented concerning the present status of each topic. A summary of past decommissioning experience in Member States is presented in the Appendix. The report, with its discussions of necessary considerations, available operational methods, and waste management practices, together with supporting references, provides an appreciation of the activities that comprise decommissioning of nuclear facilities. It is anticipated that the information presented in the report should prove useful to persons concerned with the development of plans for the decommissioning of retired nuclear facilities

  20. Alpha Decontamination and Disassembly Pilot Facility. Final report

    International Nuclear Information System (INIS)

    Daugherty, B.A.; Clark, H.E.

    1985-04-01

    The Alpha Decontamination and Disassembly (AD and D) Pilot Facility was built to develop and demonstrate a reference process for the decontamination and size reduction of noncombustible transuranic (TRU) waste. The goals of the reference process were to remove >99% of the surface contamination to the high-level waste tanks, and to achieve volume reduction factors greater than 15:1. Preliminary bench-scale decontamination work was accomplished at Savannah River Laboratory (SRL), establishing a reference decontamination process. Initially, the pilot facility did not achieve the decontamination goals. As the program continued, and modifications to the process were made, coupon analysis idicated that 99% of the surface contamination was removed to the high-level drain system. Prior to the AD and D Pilot Facility, no size reduction work had been done at SRL. Several other Department of Energy (DOE) facilities were experimenting with plasma arc torches for size reduction work. Their methods were employed in the AD and D hot cell with moderate success. The experimental work concluded with recommendations for further testing of other size reduction techniques. 11 figs., 6 tabs

  1. Spent-fuel disassembly and canning programs at the Barnwell Nuclear Fuel Plant (BNFP)

    International Nuclear Information System (INIS)

    Townes, G.A.

    1980-02-01

    Doubling pool storage and tripling truck cask shipping capability appear feasible based on preliminary development work performed at the BNFP. This would be accomplished by disassembly of the fuel assembly and canning of the fuel pins. The dry, remote disassembly and canning in the headend cells offer adequate rates, easily controlled operator exposure, and visual inspection of the fuel pins and operations through shielded windows

  2. Studies of fast reactor disassembly using a Bethe-Tait computer code

    International Nuclear Information System (INIS)

    Ludwig, J.C.

    1978-10-01

    The advantages of the fast reactor are given and the general design outlined. Loss of Flow and Transient Overpower faults are possible; the potential consequences of such incidents are analysed using a deterministic approach. The course of an incident is split into several stages; of these only predisassembly and disassembly are considered. Predisassembly computer codes are described in general, and several particular codes are examined in more detail, based on a literature survey. The results and implications of disassembly calculations using the code EXTRA are presented. Here, the effects of several factors, such as the presence of retained fission gases and possible restraints on fuel motion, are investigated. Some comparisons are made with published results from the VENUS-II disassembly code. A general conclusion is that under some circumstances, the yield predicted during disassembly is relatively insensitive to modelling assumptions, and a simple code such as EXTRA may prove adequate if explicit core displacements are not required. A major factor in determining the yield of the disassembly phase is confirmed as being the rate of reactivity insertion during disassembly, as predicted by a predisassembly code. (U.K.)

  3. Out pile test of a disassembly tool for the intermediate examination of nuclear fuel rods

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jintae; Joung, Chang-Young; Ahn, Sung-Ho; Yang, Tae-Ho; Jang, Seo-Yoon; Park, Seung-Jae [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    The two fuel rod assemblies are assembled with a bayonet coupler, and the non-instrumented fuel rod assembly can be disassembled for intermediate examination. A tool to disassemble the non-instrumented fuel rod assembly from the test rig was developed, and steel wires are connected to the tool to operate release function. In this study, an assembly plug with a quick plug typed bayonet coupler and the accompanying disassembly tool was designed to prevent the interference problem. A test rig mockup was fabricated, and performance test was carried out in the laboratory. And, the out pile test was also carried out in the single channel test loop established in the KAERI. In this study, a modified coupler design to disassemble the non-instrumented fuel rod assembly from the test rig for the intermediate examination was suggested to solve interference problem of previous design. The performance of the modified design was verified by test mockup fabricated with the modified coupler design and accompanied disassembly tool design. Finally, out pile test was carried out in the single channel test loop in the KAERI, and the test rig and the disassembly tool showed good performance and reliability. The developed technique will be useful to the periodic intermediate examination of nuclear fuel rods.

  4. Out pile test of a disassembly tool for the intermediate examination of nuclear fuel rods

    International Nuclear Information System (INIS)

    Hong, Jintae; Joung, Chang-Young; Ahn, Sung-Ho; Yang, Tae-Ho; Jang, Seo-Yoon; Park, Seung-Jae

    2016-01-01

    The two fuel rod assemblies are assembled with a bayonet coupler, and the non-instrumented fuel rod assembly can be disassembled for intermediate examination. A tool to disassemble the non-instrumented fuel rod assembly from the test rig was developed, and steel wires are connected to the tool to operate release function. In this study, an assembly plug with a quick plug typed bayonet coupler and the accompanying disassembly tool was designed to prevent the interference problem. A test rig mockup was fabricated, and performance test was carried out in the laboratory. And, the out pile test was also carried out in the single channel test loop established in the KAERI. In this study, a modified coupler design to disassemble the non-instrumented fuel rod assembly from the test rig for the intermediate examination was suggested to solve interference problem of previous design. The performance of the modified design was verified by test mockup fabricated with the modified coupler design and accompanied disassembly tool design. Finally, out pile test was carried out in the single channel test loop in the KAERI, and the test rig and the disassembly tool showed good performance and reliability. The developed technique will be useful to the periodic intermediate examination of nuclear fuel rods

  5. Effects of reactive oxygen species on cellular wall disassembly of banana fruit during ripening.

    Science.gov (United States)

    Cheng, Guiping; Duan, Xuewu; Shi, John; Lu, Wangjin; Luo, Yunbo; Jiang, Weibo; Jiang, Yueming

    2008-07-15

    Fruit softening is generally attributed to cell wall disassembly. Experiments were conducted to investigate effects of various reactive oxygen species (ROS) on in vitro cellular wall disassembly of harvested banana fruit. The alcohol-extracted insoluble residue (AEIR) was obtained from the pulp tissues of banana fruit at various ripening stages and then used to examine the disassembly of cellular wall polysaccharides in the presence of superoxide anion (O2(-)), hydrogen peroxide (H2O2) or hydroxyl radical (OH) and their scavengers. The presence of OH accelerated significantly disassembly of cellular wall polysaccharides in terms of the increase in contents of total sugars released and uronic acid, and the decrease in molecular mass of soluble polysaccharides, using gel permeation chromatography. However, the treatment with H2O2 or O2(-) showed no significant effect on the disassembly of cellular wall polysaccharides. Furthermore, the degradation of the de-esterified AEIR was more susceptible to OH attack than the esterified AEIR. In addition, the effect of OH could be inhibited in the presence of OH scavenger. This study suggests that disassembly of cellular wall polysaccharides could be initiated by OH as the solublisation of the polysaccharides increased, which, in turn, accelerated fruit softening. Copyright © 2008 Elsevier Ltd. All rights reserved.

  6. VENUS-2, Reactor Kinetics with Feedback, 2-D LMFBR Disassembly Excursions

    International Nuclear Information System (INIS)

    Jackson, J.F.; Nicholson, R.B.; Weber, D.P.

    1980-01-01

    1 - Description of problem or function: VENUS-2 is an improved edition of the VENUS fast-reactor disassembly program. It is a two- dimensional (r-z) coupled neutronics-hydrodynamics code that calculates the dynamic behavior of an LMFBR during a prompt-critical disassembly excursion. It calculates the power history and fission energy release as well as the space-time histories of the fuel temperatures, core material pressures, and core material motions. Reactivity feedback effects due to Doppler broadening and reactor material motion are taken into account. 2 - Method of solution: The power and energy release are calculated using a point-kinetics formulation with up to six delayed neutron groups. The reactivity is a combination of an input driving function and feedback effects due to Doppler broadening and material motion. An adiabatic model is used to calculate the temperature increase throughout the reactor based on an initial temperature distribution and power profile provided as input data. These temperatures are, in turn, converted to fuel pressures through one of several equation of state options provided. The material motion that results from the pressure buildup is calculated by a direct finite difference solution of a set of two-dimensional (r-z) hydrodynamics equations. This is done in Lagrangian coordinates. The reactivity change associated with this motion is calculated by first-order perturbation theory. The displacements are also used to adjust the fuel densities as required for the density dependent equation-of- state option. An automatic time-step-size selection scheme is provided. 3 - Restrictions on the complexity of the problem: VENUS-2 is written so that the dimensions of the storage arrays can be readily changed to accommodate a broad range of problem sizes. In the base version, the total number of mesh intervals is restricted such that (NR+3)*(NZ+3) is less than 700, where NR and NZ are the total number of mesh intervals in the r and z

  7. AGR-3/4 Irradiation Test Train Disassembly and Component Metrology First Look Report

    Energy Technology Data Exchange (ETDEWEB)

    Stempien, John Dennis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rice, Francine Joyce [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Winston, Philip Lon [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    The AGR-3/4 experiment was designed to study fission product transport within graphitic matrix material and nuclear-grade graphite. To this end, this experiment consisted of 12 capsules, each fueled with 4 compacts containing UCO TRISO particles as driver fuel and 20 UCO designed-to-fail (DTF) fuel particles in each compact. The DTF fuel was fabricated with a thin pyrocarbon layer which was intended to fail during irradiation and provide a source of fission products. These fission products could then migrate through the compact and into the surrounding concentric rings of graphitic matrix material and/or nuclear graphite. Through post-irradiation examination (PIE) of the rings (including physical sampling and gamma scanning) fission product concentration profiles within the rings can be determined. These data can be used to elucidate fission product transport parameters (e.g. diffusion coefficients within the test materials) which will be used to inform and refine models of fission product transport. After irradiation in the Advanced Test Reactor (ATR) had been completed in April 2014, the AGR-3/4 experiment was shipped to the Hot Fuel Examination Facility (HFEF) at the Materials and Fuels Complex (MFC) for inspection, disassembly, and metrology. The AGR-3/4 test train was received at MFC in two separate shipments between February and April 2015. Visual examinations of the test train exterior did not indicate dimensional distortion, and only two small discolored areas were observed at the bottom of Capsules 8 and 9. No corresponding discoloration was found on the inside of these capsules, however. Prior to disassembly, the two test train sections were subject to analysis via the Precision Gamma Scanner (PGS), which did not indicate that any gross fuel relocation had occurred. A series of specialized tools (including clamps, cutters, and drills) had been designed and fabricated in order to carry out test train disassembly and recovery of capsule components (graphite

  8. AGR-3/4 Irradiation Test Train Disassembly and Component Metrology First Look Report

    Energy Technology Data Exchange (ETDEWEB)

    Stempien, John Dennis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rice, Francine Joyce [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Winston, Philip Lon [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-03-01

    The AGR-3/4 experiment was designed to study fission product transport within graphitic matrix material and nuclear-grade graphite. To this end, this experiment consisted of 12 capsules, each fueled with 4 compacts containing UCO TRISO particles as driver fuel and 20 UCO designed-to-fail (DTF) fuel particles in each compact. The DTF fuel was fabricated with a thin pyrocarbon layer which was intended to fail during irradiation and provide a source of fission products. These fission products could then migrate through the compact and into the surrounding concentric rings of graphitic matrix material and/or nuclear graphite. Through post-irradiation examination (PIE) of the rings (including physical sampling and gamma scanning) fission product concentration profiles within the rings can be determined. These data can be used to elucidate fission product transport parameters (e.g. diffusion coefficients within the test materials) which will be used to inform and refine models of fission product transport. After irradiation in the Advanced Test Reactor (ATR) had been completed in April 2014, the AGR-3/4 experiment was shipped to the Hot Fuel Examination Facility (HFEF) at the Materials and Fuels Complex (MFC) for inspection, disassembly, and metrology. The AGR-3/4 test train was received at MFC in two separate shipments between February and April 2015. Visual examinations of the test train exterior did not indicate dimensional distortion, and only two small discolored areas were observed at the bottom of Capsules 8 and 9. No corresponding discoloration was found on the inside of these capsules, however. Prior to disassembly, the two test train sections were subject to analysis via the Precision Gamma Scanner (PGS), which did not indicate that any gross fuel relocation had occurred. A series of specialized tools (including clamps, cutters, and drills) had been designed and fabricated in order to carry out test train disassembly and recovery of capsule components (graphite

  9. ARC: A compact, high-field, disassemblable fusion nuclear science facility and demonstration power plant

    Science.gov (United States)

    Sorbom, Brandon; Ball, Justin; Palmer, Timothy; Mangiarotti, Franco; Sierchio, Jennifer; Bonoli, Paul; Kasten, Cale; Sutherland, Derek; Barnard, Harold; Haakonsen, Christian; Goh, Jon; Sung, Choongki; Whyte, Dennis

    2014-10-01

    The Affordable, Robust, Compact (ARC) reactor conceptual design aims to reduce the size, cost, and complexity of a combined Fusion Nuclear Science Facility (FNSF) and demonstration fusion pilot power plant. ARC is a 270 MWe tokamak reactor with a major radius of 3.3 m, a minor radius of 1.1 m, and an on-axis magnetic field of 9.2 T. ARC has Rare Earth Barium Copper Oxide (REBCO) superconducting toroidal field coils with joints to allow disassembly, allowing for removal and replacement of the vacuum vessel as a single component. Inboard-launched current drive of 25 MW LHRF power and 13.6 MW ICRF power is used to provide a robust, steady state core plasma far from disruptive limits. ARC uses an all-liquid blanket, consisting of low pressure, slowly flowing Fluorine Lithium Beryllium (FLiBe) molten salt. The liquid blanket acts as a working fluid, coolant, and tritium breeder, and minimizes the solid material that can become activated. The large temperature range over which FLiBe is liquid permits blanket operation at 800-900 K with single phase fluid cooling and allows use of a high-efficiency Brayton cycle for electricity production in the secondary coolant loop.

  10. Selenide isotope generator for the Galileo mission. GDS disassembly report

    International Nuclear Information System (INIS)

    1978-11-01

    The GDS-1 was disassembled to determine the cause for the rapid degradation of the output power. Unfortunately, it was not possible to relate the observations to direct causes for the degradation. However, some positive statements can be made which have an impact on the flight program. First, the outgassing and gas management techniques were shown to be adequate to maintain clean conditions within the generator. Second, the non-modular components within the generator including the receptacles on the housing were not affected by the thermal environment during operation of GDS-1. Third, a significant amount of sublimation of the P-legs has occurred during the relatively short life of 2000 + hours as shown by the bullet nosing of the legs and deposits on the cold end hardware. The fact that the generator atmosphere was not 100% xenon may have some bearing on this observation but the statement is still accurate. Fourth, all exposed N-legs display cracks and/or chips. Fifth, a great deal of misalignment of both N and P-legs was seen both visually and with radiographs. Although no definite conclusions can be made concerning the cause for the rapid degradation of performance, several of the observed conditions within the module could possibly contribute to that fact. They are: cracks in N-legs (increased resistance); deposits on edges of BeO discs (shorting of thermoelectric circuit); and bullet nosing of P-legs (increased resistance). It remains to be shown if any of these effects or the follower hangup described earlier contributed to the poor performance of GDS-1 or if another effect as yet unknown was the important factor

  11. Accomplishment of JT-60U disassembly work dealing with radioactive components

    International Nuclear Information System (INIS)

    Ikeda, Yoshitaka

    2015-01-01

    The upgrade of the JT-60U to the superconducting tokamak 'JT-60SA' has been carried out to contribute the early realization of fusion energy by addressing key physics issues relevant for ITER and DEMO. Disassembly of the JT-60U tokamak was required so as to newly install the JT-60SA torus at the same position in the torus hall. The JT-60U tokamak was featured by the complicated and welded structure against the strong electromagnetic force, and by the radioactivation due to deuterium-deuterium (D-D) reactions of 1.5x10"2"0 (n) in total. Since this work was the first experience of disassembling a large radioactivated fusion device in Japan, careful preparations of disassembly activities, including treatment of the radioactivated materials and safety work, have been made. About 13,000 components with a total weight of more than 5,400 tonnes were removed from the torus hall and stored safely in storage facilities. All disassembly components were stored with recording the data such as dose rate, weight and kind of material, so as to apply the clearance level regulation in future. It was confirmed that the main radioactive material of the disassembly components was the stainless steel and that its dose rate was almost background level (∼0.1 μSv/h) at ∼10 m far from the vacuum vessel. It seems that the disassembly components with background dose level are in the clearance level. The assembly of JT-60SA tokamak has started in January 2013 after this disassembly of the JT-60U tokamak. (author)

  12. A Label Correcting Algorithm for Partial Disassembly Sequences in the Production Planning for End-of-Life Products

    Directory of Open Access Journals (Sweden)

    Pei-Fang (Jennifer Tsai

    2012-01-01

    Full Text Available Remanufacturing of used products has become a strategic issue for cost-sensitive businesses. Due to the nature of uncertain supply of end-of-life (EoL products, the reverse logistic can only be sustainable with a dynamic production planning for disassembly process. This research investigates the sequencing of disassembly operations as a single-period partial disassembly optimization (SPPDO problem to minimize total disassembly cost. AND/OR graph representation is used to include all disassembly sequences of a returned product. A label correcting algorithm is proposed to find an optimal partial disassembly plan if a specific reusable subpart is retrieved from the original return. Then, a heuristic procedure that utilizes this polynomial-time algorithm is presented to solve the SPPDO problem. Numerical examples are used to demonstrate the effectiveness of this solution procedure.

  13. Centralized disassembly and packaging of spent fuel in the DOE spent fuel management system

    International Nuclear Information System (INIS)

    Johnson, E.R.

    1986-01-01

    In October 1984, E.R. Johnson Associates, Inc. (JAI) initiated a study of the prospective use of a centralized facility for the disassembly and packaging of spent fuel to support the various elements of the US Dept. of Energy (DOE) spent fuel management system, including facilities for monitored retrievable storage (MRS) and repositories. It was DOE's original plan to receive spent fuel at each repository where it would be disassembled and packaged (overpacked) for disposal purposes. Subsequently, DOE considered the prospective use of MRS of spent fuel as an option for providing safe and reliable management of spent fuel. This study was designed to consider possible advantages of the use of centralized facilities for disassembly and packaging of spent fuel at whose location storage facilities could be added as required. The study was divided into three principal technical tasks that covered: (a) development of requirements and criteria for the central disassembly and packaging facility and associated systems. (2) Development of conceptual designs for the central disassembly and packaging facility and associated systems. (3) Estimation of capital and operating costs involved for all system facilities and determination of life cycle costs for various scenarios of operation - for comparison with the reference system

  14. Shape memory polymer nanocomposites for application of multiple-field active disassembly: experiment and simulation.

    Science.gov (United States)

    Carrell, John; Zhang, Hong-Chao; Wang, Shiren; Tate, Derrick

    2013-11-19

    Active disassembly (AD) uses innovative materials that can perform a designed disassembly action by the application of an external field. AD provides improvements over current disassembly processes by limiting machine or manual labor and enabling batch processing for end-of-life products. With improved disassembly operations, more reuse of components and purer recycling streams may be seen. One problem with AD, however, has been with the single-field actuation because of the probability of accidental disassembly. This presentation will discuss the application of shape memory polymer (SMP) nanocomposites in a new AD process. This novel AD process requires multiple-field actuation of the SMP nanocomposite fastener. In the analysis of this AD process, thermal and magnetic field tests were performed on the SMP nanocomposite. From these tests, finite-element analysis was performed to model and simulate the multiple-field AD process. The results of the simulations provide performance variables for the AD process and show a better performance time for the SMP nanocomposite fastener than for a comparable SMP fastener.

  15. Mathematical and Simulation Modelling of Moisture Diffusion Mechanism during Plastic IC Packages Disassembly

    Directory of Open Access Journals (Sweden)

    Peng Mou

    2013-01-01

    Full Text Available Reuse of plastic IC packages disassembled from printed circuit boards (PCBs has significant environmental benefits and economic value. The interface delamination caused by moisture diffusion is the main failure mode of IC packages during the disassembling process, which greatly reduces the reusability and reliability of disassembled IC packages. Exploring moisture diffusion mechanism is a prerequisite to optimize prebaking processes before disassembling that is an effective way to avoid the interface delamination. To this end, a computational model with variable boundary conditions is developed based on the different combination state of water in IC packages. The distribution characteristics and mechanism of moisture diffusion behavior are analyzed including the humidity distribution field and the relation among baking temperature, water loss rate, and baking time during baking process, and then the results are validated by FEA simulation based on the improved definition of relative moisture concentration. Baking under variable temperature is proposed and compared with the baking process and baking efficiency under constant temperature to find out the optimized baking parameters. Finally, a set of curves which indicate the relation between baking energy consumption and temperature are determined under actual industrial baking experiments, which could be used as references to develop industrial standards for PCB disassembling process.

  16. An Intelligent Agent-Controlled and Robot-Based Disassembly Assistant

    Science.gov (United States)

    Jungbluth, Jan; Gerke, Wolfgang; Plapper, Peter

    2017-09-01

    One key for successful and fluent human-robot-collaboration in disassembly processes is equipping the robot system with higher autonomy and intelligence. In this paper, we present an informed software agent that controls the robot behavior to form an intelligent robot assistant for disassembly purposes. While the disassembly process first depends on the product structure, we inform the agent using a generic approach through product models. The product model is then transformed to a directed graph and used to build, share and define a coarse disassembly plan. To refine the workflow, we formulate “the problem of loosening a connection and the distribution of the work” as a search problem. The created detailed plan consists of a sequence of actions that are used to call, parametrize and execute robot programs for the fulfillment of the assistance. The aim of this research is to equip robot systems with knowledge and skills to allow them to be autonomous in the performance of their assistance to finally improve the ergonomics of disassembly workstations.

  17. Design and analysis of sustainable computer mouse using design for disassembly methodology

    Science.gov (United States)

    Roni Sahroni, Taufik; Fitri Sukarman, Ahmad; Agung Mahardini, Karunia

    2017-12-01

    This paper presents the design and analysis of computer mouse using Design for Disassembly methodology. Basically, the existing computer mouse model consist a number of unnecessary part that cause the assembly and disassembly time in production. The objective of this project is to design a new computer mouse based on Design for Disassembly (DFD) methodology. The main methodology of this paper was proposed from sketch generation, concept selection, and concept scoring. Based on the design screening, design concept B was selected for further analysis. New design of computer mouse is proposed using fastening system. Furthermore, three materials of ABS, Polycarbonate, and PE high density were prepared to determine the environmental impact category. Sustainable analysis was conducted using software SolidWorks. As a result, PE High Density gives the lowers amount in the environmental category with great maximum stress value.

  18. Development of the spent fuel disassembling process by utilizing the 3D graphic design technology

    International Nuclear Information System (INIS)

    Song, T. K.; Lee, J. Y.; Kim, S. H.; Yun, J. S.

    2001-01-01

    For developing the spent fuel disassembling process, the 3D graphic simulation has been established by utilizing the 3D graphic design technology which is widely used in the industry. The spent fuel disassembling process consists of a downender, a rod extraction device, a rod cutting device, a pellet extracting device and a skeleton compaction device. In this study, the 3D graphical design model of these devices is implemented by conceptual design and established the virtual workcell within kinematics to motion of each device. By implementing this graphic simulation, all the unit process involved in the spent fuel disassembling processes are analyzed and optimized. The 3D graphical model and the 3D graphic simulation can be effectively used for designing the process equipment, as well as the optimized process and maintenance process

  19. Advanced disassembling technique of irradiated driver fuel assembly for continuous irradiation of fuel pins

    International Nuclear Information System (INIS)

    Ichikawa, Shoichi; Haga, Hiroyuki; Katsuyama, Kozo; Maeda, Koji; Nishinoiri, Kenji

    2012-01-01

    It was necessary to carry out continuous irradiation tests in order to obtain the irradiation data of high burn-up fuel and high neutron dose material for FaCT (Fast Reactor Cycle Technology Development) project. There, the disassembling technique of an irradiated fuel assembly was advanced in order to realize further continuous irradiation tests. Although the conventional disassembling technique had been cutting a lower end-plug of a fuel pin needed to fix fuel pins to an irradiation vehicle, the advanced disassembling technique did not need cutting a lower end-plug. As a result, it was possible to supply many irradiated fuel pins to various continuous irradiation tests for FaCT project. (author)

  20. New findings on the onset of thermal disassembly in spallation reactions

    International Nuclear Information System (INIS)

    Napolitani, P.

    2004-09-01

    Thermal multifragmentation is the process of multi body disassembly of a hot nucleus when the excitation is almost purely thermal i.e. dynamical effects like compression (characteristic of ion-ion collisions at Fermi energy) are negligible. Suited reactions are proton induced collision or ion-ion abrasion at relativistic incident energy. Thus we measured four systems at FRS (Fragment separator, GSI, Darmstadt) in inverse kinematics: Fe 56 +p, Fe 56 +Ti(nat), Xe 136 +p, Xe 136 +Ti(nat) a 1 A*GeV. The inverse kinematics allows to observe all particles without any threshold in energy. This is a great advantage compared to experiments in direct kinematics, because only in inverse kinematics it is possible to obtain complete velocity spectra (without a hole for low velocities) for fully identified isotopes. The complex shape of the velocity spectra allows to identify the different deexcitation channels and it clearly shows the transition from a chaotic-dominated process (Gaussian cloud in velocity space) to a direct Coulomb- (or eventually expansion-) dominated process (shell of a sphere in velocity space). Different possible descriptions of the reaction process are discussed, based either on asymmetric fission or multifragmentation. The resulting physical picture is especially interesting for the Fe 56 +p, and Xe 136 +p systems: proton induced collisions could result in the split of the system in two or more fragments due to a fast break-up process. In this case, the configuration of the break-up partition is very asymmetric. The discussion will be extended to other characteristics, like the restoring of nuclear structure features in the isotopic production and the temperature dependence of the isotopic composition of the residues. (author)

  1. The Chloroplast Division Protein ARC6 Acts to Inhibit Disassembly of GDP-bound FtsZ2.

    Science.gov (United States)

    Sung, Min Woo; Shaik, Rahamthulla; TerBush, Allan D; Osteryoung, Katherine W; Vitha, Stanislav; Holzenburg, Andreas

    2018-05-16

    Chloroplasts host photosynthesis and fulfill other metabolic functions that are essential to plant life. They have to divide by binary fission to maintain their numbers throughout cycles of cell division. Chloroplast division is achieved by a complex ring-shaped division machinery located on both the inner (stromal) and the outer (cytosolic) side of the chloroplast envelope. The inner division ring (termed the Z ring) is formed by the assembly of tubulin-like FtsZ1 and FtsZ2 proteins. ARC6 is a key chloroplast division protein that interacts with the Z ring. ARC6 spans the inner envelope membrane, is known to stabilize or maintain the Z ring, and anchors the Z ring to the inner membrane through interaction with FtsZ2. The underlying mechanism of Z-ring stabilization is not well understood. Here, biochemical and structural characterization of ARC6 was conducted using light scattering, sedimentation, and light and transmission electron microscopy. The recombinant protein was purified as a dimer. The results indicated that a truncated form of ARC6 (tARC6), representing the stromal portion of ARC6, affects FtsZ2 assembly without forming higher-order structures, and exerts its effect via FtsZ2 dynamics. tARC6 prevented GDP-induced FtsZ2 disassembly and caused a significant net increase in FtsZ2 assembly when GDP was present. Single particle analysis and 3D reconstruction were performed to elucidate the structural basis of ARC6 activity. Together, the data reveal that a dimeric form of tARC6 binds to FtsZ2 filaments and does not increase FtsZ polymerization rates but rather inhibits GDP-associated FtsZ2 disassembly. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Pilot scale, alpha disassembly and decontamination facility at the Savannah River Laboratory

    International Nuclear Information System (INIS)

    Cadieux, J.R.; Becker, G.W. Jr.; Richardson, G.W.; Coogler, A.L.

    1982-01-01

    An alpha-contained pilot facility is being built at the Savannah River Laboratory (SRL) for research into the disassembly and dcontamination of noncombustible, Transuranic (TRU) waste. The design and program objectives for the facility are presented along with the initial test results from laboratory scale decontamination experiments with Pu-238 and Cm-244

  3. Phosphatase PP2A and microtubule-mediated pulling forces disassemble centrosomes during mitotic exit

    Directory of Open Access Journals (Sweden)

    Stephen J. Enos

    2018-01-01

    Full Text Available Centrosomes are microtubule-nucleating organelles that facilitate chromosome segregation and cell division in metazoans. Centrosomes comprise centrioles that organize a micron-scale mass of protein called pericentriolar material (PCM from which microtubules nucleate. During each cell cycle, PCM accumulates around centrioles through phosphorylation-mediated assembly of PCM scaffold proteins. During mitotic exit, PCM swiftly disassembles by an unknown mechanism. Here, we used Caenorhabditis elegans embryos to determine the mechanism and importance of PCM disassembly in dividing cells. We found that the phosphatase PP2A and its regulatory subunit SUR-6 (PP2ASUR-6, together with cortically directed microtubule pulling forces, actively disassemble PCM. In embryos depleted of these activities, ∼25% of PCM persisted from one cell cycle into the next. Purified PP2ASUR-6 could dephosphorylate the major PCM scaffold protein SPD-5 in vitro. Our data suggest that PCM disassembly occurs through a combination of dephosphorylation of PCM components and force-driven fragmentation of the PCM scaffold.

  4. Optimization of Two-Level Disassembly/Remanufacturing/Assembly System with an Integrated Maintenance Strategy

    Directory of Open Access Journals (Sweden)

    Zouhour Guiras

    2018-04-01

    Full Text Available With an increase of environmental pressure on economic activities, reverse flow is increasingly important. It seeks to save resources, eliminate waste, and improve productivity. This paper investigates the optimization of the disassembly, remanufacturing and assembly system, taking into account assembly-disassembly system degradation. An analytical model is developed to consider disassembly, remanufacturing of used/end-of-life product and assembly of the finished product. The finished product is composed of remanufactured and new components. A maintenance policy is sequentially integrated to reduce the system unavailability. The aim of this study is to help decision-makers, under certain conditions, choose the most cost-effective process for them to satisfy the customer as well as to adapt to the potential risk that can perturb the disassembly-assembly system. A heuristic is developed to determine the optimal ordered date of the used end-of-life product as well as the optimum release dates of new external components. The results reveal that considering some remanufacturing and purchase components costs, the proposed model is more economical in comparison with a model without remanufactured parts. Numerical results are provided to illustrate the impact of the variation of the ordering cost and quality of the used end-of-life product on the system profitability. Finally, the risk due to system repair periods is discussed, which has an impact on managerial decision-making.

  5. Improved Nondestructive Disassembly Process using Augmented Reality and RFID Product/Part Tracking

    Directory of Open Access Journals (Sweden)

    Ile Mircheski

    2017-11-01

    Full Text Available The waste from electric and electronic equipment and discarded automobiles in the past grew rapidly and resulted with waste in billions of tones. The aim of this paper is to present an improved non-destructive disassembly process of electromechanical products using augmented reality based devices, such as glasses, tablets or mobile phones, and RFID technology for valuable product/part tracking. The proposed method includes tagging of components of interest in the product assembly by using a RFID tag. The valuable product is marked with specific ID number written in the RFID tag, in order to declare the product. The relevant data such as material and weight of components, guidelines for non-destructive disassembly for the valuable product and removing of component of interest will be obtained with the assistance of RFID tag and a centralized database. This modular system offers guidelines for the non-destructive disassembly process for obtaining valuable component of interest intended for easy repairs, remanufacture, reuse or recycling. The guidelines are in video presentation format using augmented reality for easy visualization of non-destructive disassembly process. The benefits of proposed modular system includes biggest percentage of reuse of the valuable components, easy maintaining, improved material recycling, environmental protection and greater total return form end of life products.

  6. Hybrid disassembly system for cellular telephone end-of-life treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kniebel, M.; Basdere, B.; Seliger, G. [Technical Univ. Berlin, Inst. for Machine Tools and Factory Management, Dept. of Assembly Technology and Factory Management, Berlin (Germany)

    2004-07-01

    Concern over the negative environmental impacts associated with the production, use, and end-of-life (EOL) of cellular telephones is particularly high due to large production volumes and characteristically short time scales of technological and stylistic obsolescence. Landfilled or incinerated cellular telephones create the potential for release of toxic substances. The European legislation has passed the directive on Waste of Electrical and Electronic Equipment (WEEE) to regulate their collection and appropriate end-of-life treatment. Manufacturers must conduct material recycling or remanufacturing processes to recover resources. While recovery rates can hardly be met economically by material recycling, remanufacturing and reusing cellular phones is developing into a reasonable alternative. Both end-of-life options require disassembly processes for WEEE compliant treatment. Due to the high number of different cell phone variants and their typical design that fits components into tight enclosing spaces, cellular phone disassembly becomes a challenging task. These challenges and the expected high numbers of phones to be returned in the course of the WEEE urges for automated disassembly. A hybrid disassembly system has been developed to ensure the mass-treatment of obsolete cellular phones. It has been integrated into a prototypical remanufacturing factory for cellular phones that has been planned based on market data. (orig.)

  7. Conceptual design report for the mechanical disassembly of Fort St. Vrain fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Lord, D.L. [Westinghouse Idaho Nuclear Co., Inc., Idaho Falls, ID (United States); Wadsworth, D.C.; Sekot, J.P.; Skinner, K.L. [EG and G Idaho, Inc., Idaho Falls, ID (United States)

    1993-04-01

    A conceptual design study was prepared that: (1) reviewed the operations necessary to perform the mechanical disassembly of Fort St. Vrain fuel elements; (2) contained a description and survey of equipment capable of performing the necessary functions; and (3) performed a tradeoff study for determining the preferred concepts and equipment specifications. A preferred system was recommended and engineering specifications for this system were developed.

  8. Nano-functionalized filamentous fungus hyphae with fast reversible macroscopic assembly & disassembly features.

    Science.gov (United States)

    Wang, Haiying; Li, Xiaorui; Chai, Liyuan; Zhang, Liyuan

    2015-05-18

    A uniform decoration of hyphae by polyaniline nanoparticles (PANI NPs) was achieved here. This novel hybrid structure can be effectively assembled into a film by filtration and disassembled in water by shaking. This reversible process is very fast, which promises applications in nanomaterials including adsorption.

  9. Conceptual design report for the mechanical disassembly of Fort St. Vrain fuel elements

    International Nuclear Information System (INIS)

    Lord, D.L.; Wadsworth, D.C.; Sekot, J.P.; Skinner, K.L.

    1993-04-01

    A conceptual design study was prepared that: (1) reviewed the operations necessary to perform the mechanical disassembly of Fort St. Vrain fuel elements; (2) contained a description and survey of equipment capable of performing the necessary functions; and (3) performed a tradeoff study for determining the preferred concepts and equipment specifications. A preferred system was recommended and engineering specifications for this system were developed

  10. DISA- a computer code for accident analysis of fast reactor during disassembly phase

    International Nuclear Information System (INIS)

    Yadav, R.D.S.; Gupta, H.P.

    2005-01-01

    Analysis of the hypothetical transients in fast rectors that result in the disassembly of the reactor generally consists of three phases. In the phase-l, some initiating event like control rod ejection, coolant pump failure etc. is assumed to have taken place which leads the reactor to prompt critical state where fuel melting, sodium voiding etc. take place. In fast reactor normally the fuel is not in the optimum shape and further positive reactivity may be introduced into the system due to fuel melting. Fuel slumping is assumed to take place in this phase. If prompt criticality is reached as a result of the first phase, then disassembly phase is assumed to start. In this phase the neutron transient is followed till it is terminated by the disassembly of the core which takes place due to generation of high pressure gradients and which lead the core material to move from more worth region to less worth region. Doppler feed back is taken into account and reactivity feedback due to material movement is calculated by solving the hydrodynamics equations. The third phase will calculate the effect of this transient on the reactor vessel and containment. A computer code DISA for fast reactor DISAssembly phase, which is similar to the well known code VENUS has been developed. (author)

  11. Pit disassembly and conversion demonstration environmental assessment and research and development activities

    International Nuclear Information System (INIS)

    1998-08-01

    A significant portion of the surplus plutonium is in the form of pits, a nuclear weapons component. Pits are composed of plutonium which is sealed in a metallic shell. These pits would need to be safely disassembled and permanently converted to an unclassified form that would be suitable for long-term disposition and international inspection. To determine the feasibility of an integrated pit disassembly and conversion system, a Pit Disassembly and Conversion Demonstration is proposed to take place at the Los Alamos National Laboratory (LANL). This demonstration would be done in existing buildings and facilities, and would involve the disassembly of up to 250 pits and conversion of the recovered plutonium to plutonium metal ingots and plutonium dioxide. This demonstration also includes the conversion of up to 80 kilograms of clean plutonium metal to plutonium dioxide because, as part of the disposition process, some surplus plutonium metal may be converted to plutonium dioxide in the same facility as the surplus pits. The equipment to be used for the proposed demonstration addressed in this EA would use some parts of the Advanced Recovery and Integrated Extraction System (ARIES) capability, other existing equipment/capacities, plus new equipment that was developed at other sites. In addition, small-scale R and D activities are currently underway as part of the overall surplus plutonium disposition program. These R and D activities are related to pit disassembly and conversion, MOX fuel fabrication, and immobilization (in glass and ceramic forms). They are described in Section 7.0. On May 16, 1997, the Office of Fissile Materials Disposition (MD) notified potentially affected states and tribes that this EA would be prepared in accordance with NEPA. This EA has been prepared to provide sufficient information for DOE to determine whether a Finding of No Significant Impact (FONSI) is warranted or whether an EIS must be prepared

  12. Disassembly and physical separation of electric/electronic components layered in printed circuit boards (PCB).

    Science.gov (United States)

    Lee, Jaeryeong; Kim, Youngjin; Lee, Jae-chun

    2012-11-30

    Although printed circuit boards (PCBs) contain various elements, only the major elements (i.e., those with content levels in wt% or over grade) of and precious metals (e.g., Ag, Au, and platinum groups) contained within PCBs can be recycled. To recover other elements from PCBs, the PCBs should be properly disassembled as the first step of the recycling process. The recovery of these other elements would be beneficial for efforts to conserve scarce resources, reuse electric/electronic components (EECs), and eliminate environmental problems. This paper examines the disassembly of EECs from wasted PCBs (WPCBs) and the physical separation of these EECs using a self-designed disassembling apparatus and a 3-step separation process of sieving, magnetic separation, and dense medium separation. The disassembling efficiencies were evaluated by using the ratio of grinding area (E(area)) and the weight ratio of the detached EECs (E(weight)). In the disassembly treatment, these efficiencies were improved with an increase of grinder speed and grinder height. 97.7% (E(area)) and 98% (E(weight)) could be accomplished ultimately by 3 repetitive treatments at a grinder speed of 5500 rpm and a grinder height of 1.5mm. Through a series of physical separations, most groups of the EECs (except for the diode, transistor, and IC chip groups) could be sorted at a relatively high separation efficiency of about 75% or more. To evaluate the separation efficiency with regard to the elemental composition, the distribution ratio (R(dis)) and the concentration ratio (R(conc)) were used. 15 elements could be separated with the highest R(dis) and R(conc) in the same separated division. This result implies that the recyclability of the elements is highly feasible, even though the initial content in EECs is lower than several tens of mg/kg. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Modelling disassembled fuel bundles using CATHENA MOD-3.5a under LOCA/LOECC conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lei, Q M; Sanderson, D B; Dutton, R [Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs.

    1996-12-31

    CATHENA MOD-3.5a is a multipurpose thermalhydraulic computer code developed primarily to analyse postulated loss-of-coolant scenarios for CANDU nuclear reactors. The code contains a generalized heat transfer package that enables it to model the behaviour of a fuel channel in great detail. Throughout the development of the CATHENA code, considerable effort has been devoted to evaluating, validating and documenting its overall capability as a design and safety assessment tool. Specific attention has focused on its ability to predict fuel channel behaviour under postulated accident conditions. This paper describes an investigation of CATHENA`s ability to predict the thermal-chemical responses of a fuel channel in which the 37-element bundles were assumed to disassemble and rearrange into a closed-packed stack of elements at the bottom of the pressure tube. A representative disassembled bundle geometry was modelled during a simulated loss-of-coolant accident scenario using CATHENA MOD-3.5a/Rev 0, with superheated steam being the only coolant available. Thermal conduction in the radial and circumferential directions was calculated for individual fuel elements, the pressure tube, and the calandria tube. Radiation view factors for the intact and disassembled bundle geometries were calculated using a CATHENA utility program. Inter-element metal-to-metal contact was accounted for using the CATHENA solid-solid contact model. An offset pressure-tube configuration, representing a partially sagged pressure tube, and the effect of steam starvation on the exothermic zirconium-steam reaction, were included in the CATHENA model. The CATHENA-predicted results show a dramatic suppression of heat generation from the zirconium-steam reaction when bundle disassembly is initiated. The predicted results show a smaller temperature increase in the fuel sheaths and the pressure tube for the disassembled bundle geometry, compared to the temperature excursion for the intact bundle. (author

  14. Low cytoplasmic pH reduces ER-Golgi trafficking and induces disassembly of the Golgi apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Soonthornsit, Jeerawat [Laboratory for Cell and Developmental Biology, Department of Molecular Biosciences, Faculty of Life Sciences, Kyoto Sangyo University, Motoyama, Kamigamo, Kita, Kyoto 603-8555 (Japan); Yamaguchi, Yoko; Tamura, Daisuke [Division of Life Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192 (Japan); Ishida, Ryuichi; Nakakoji, Yoko; Osako, Shiho [Laboratory for Cell and Developmental Biology, Department of Molecular Biosciences, Faculty of Life Sciences, Kyoto Sangyo University, Motoyama, Kamigamo, Kita, Kyoto 603-8555 (Japan); Yamamoto, Akitsugu [Department of Animal Bioscience, Nagahama Institute of Bio-Science and Technology, 266 Tamura, Nagahama, Shiga, 526‐0829 (Japan); Nakamura, Nobuhiro, E-mail: osaru3@cc.kyoto-su.ac.jp [Laboratory for Cell and Developmental Biology, Department of Molecular Biosciences, Faculty of Life Sciences, Kyoto Sangyo University, Motoyama, Kamigamo, Kita, Kyoto 603-8555 (Japan); Division of Life Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192 (Japan)

    2014-11-01

    The Golgi apparatus was dramatically disassembled when cells were incubated in a low pH medium. The cis-Golgi disassembled quickly, extended tubules and spread to the periphery of cells within 30 min. In contrast, medial- and trans-Golgi were fragmented in significantly larger structures of smaller numbers at a slower rate and remained largely in structures distinct from the cis-Golgi. Electron microscopy revealed the complete disassembly of the Golgi stack in low pH treated cells. The effect of low pH was reversible; the Golgi apparatus reassembled to form a normal ribbon-like structure within 1–2 h after the addition of a control medium. The anterograde ER to Golgi transport and retrograde Golgi to ER transport were both reduced under low pH. Phospholipase A{sub 2} inhibitors (ONO, BEL) effectively suppressed the Golgi disassembly, suggesting that the phospholipase A{sub 2} was involved in the Golgi disassembly. Over-expression of Rab1, 2, 30, 33 and 41 also suppressed the Golgi disassembly under low pH, suggesting that they have protective role against Golgi disassembly. Low pH treatment reduced cytoplasmic pH, but not the luminal pH of the Golgi apparatus, strongly suggesting that reduction of the cytoplasmic pH triggered the Golgi disassembly. Because a lower cytoplasmic pH is induced in physiological or pathological conditions, disassembly of the Golgi apparatus and reduction of vesicular transport through the Golgi apparatus may play important roles in cell physiology and pathology. Furthermore, our findings indicated that low pH treatment can serve as an important tool to analyze the molecular mechanisms that support the structure and function of the Golgi apparatus. - Highlights: • The Golgi apparatus reversibly disassembles by low pH treatment. • The cis-Golgi disassembles quickly generating tubular structures. • Both anterograde and retrograde transport between the ER and the Golgi apparatus are reduced. • Phospholipase A{sub 2} inhibitors (ONO

  15. Low cytoplasmic pH reduces ER-Golgi trafficking and induces disassembly of the Golgi apparatus.

    Science.gov (United States)

    Soonthornsit, Jeerawat; Yamaguchi, Yoko; Tamura, Daisuke; Ishida, Ryuichi; Nakakoji, Yoko; Osako, Shiho; Yamamoto, Akitsugu; Nakamura, Nobuhiro

    2014-11-01

    The Golgi apparatus was dramatically disassembled when cells were incubated in a low pH medium. The cis-Golgi disassembled quickly, extended tubules and spread to the periphery of cells within 30 min. In contrast, medial- and trans-Golgi were fragmented in significantly larger structures of smaller numbers at a slower rate and remained largely in structures distinct from the cis-Golgi. Electron microscopy revealed the complete disassembly of the Golgi stack in low pH treated cells. The effect of low pH was reversible; the Golgi apparatus reassembled to form a normal ribbon-like structure within 1-2h after the addition of a control medium. The anterograde ER to Golgi transport and retrograde Golgi to ER transport were both reduced under low pH. Phospholipase A2 inhibitors (ONO, BEL) effectively suppressed the Golgi disassembly, suggesting that the phospholipase A2 was involved in the Golgi disassembly. Over-expression of Rab1, 2, 30, 33 and 41 also suppressed the Golgi disassembly under low pH, suggesting that they have protective role against Golgi disassembly. Low pH treatment reduced cytoplasmic pH, but not the luminal pH of the Golgi apparatus, strongly suggesting that reduction of the cytoplasmic pH triggered the Golgi disassembly. Because a lower cytoplasmic pH is induced in physiological or pathological conditions, disassembly of the Golgi apparatus and reduction of vesicular transport through the Golgi apparatus may play important roles in cell physiology and pathology. Furthermore, our findings indicated that low pH treatment can serve as an important tool to analyze the molecular mechanisms that support the structure and function of the Golgi apparatus. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Self-assembly and optically triggered disassembly of hierarchical dendron-virus complexes

    NARCIS (Netherlands)

    Kostiainen, Mauri A.; Kasyutich, Oksana; Cornelissen, Jeroen Johannes Lambertus Maria; Nolte, Roeland J.M.

    2010-01-01

    Nature offers a vast array of biological building blocks that can be combined with synthetic materials to generate a variety of hierarchical architectures. Viruses are particularly interesting in this respect because of their structure and the possibility of them functioning as scaffolds for the

  17. Assembly, operation and disassembly manual for the Battelle Large Volume Water Sampler (BLVWS)

    International Nuclear Information System (INIS)

    Thomas, V.W.; Campbell, R.M.

    1984-12-01

    Assembly, operation and disassembly of the Battelle Large Volume Water Sampler (BLVWS) are described in detail. Step by step instructions of assembly, general operation and disassembly are provided to allow an operator completely unfamiliar with the sampler to successfully apply the BLVWS to his research sampling needs. The sampler permits concentration of both particulate and dissolved radionuclides from large volumes of ocean and fresh water. The water sample passes through a filtration section for particle removal then through sorption or ion exchange beds where species of interest are removed. The sampler components which contact the water being sampled are constructed of polyvinylchloride (PVC). The sampler has been successfully applied to many sampling needs over the past fifteen years. 9 references, 8 figures

  18. A Trio-Rac1-PAK1 signaling axis drives invadopodia disassembly

    Science.gov (United States)

    Moshfegh, Yasmin; Bravo-Cordero, Jose Javier; Miskolci, Veronika; Condeelis, John; Hodgson, Louis

    2014-01-01

    Rho family GTPases control cell migration and participate in the regulation of cancer metastasis. Invadopodia, associated with invasive tumor cells, are crucial for cellular invasion and metastasis. To study Rac1 GTPase in invadopodia dynamics, we developed a genetically-encoded, single-chain Rac1 Fluorescence Resonance Energy Transfer (FRET) biosensor. The biosensor shows Rac1 activity exclusion from the core of invadopodia, and higher activity when invadopodia disappear, suggesting that reduced Rac1 activity is necessary for their stability, and Rac1 activation is involved in disassembly. Photoactivating Rac1 at invadopodia confirmed this previously-unknown Rac1 function. We built an invadopodia disassembly model, where a signaling axis involving TrioGEF, Rac1, PAK1, and phosphorylation of cortactin, causing invadopodia dissolution. This mechanism is critical for the proper turnover of invasive structures during tumor cell invasion, where a balance of proteolytic activity and locomotory protrusions must be carefully coordinated to achieve a maximally invasive phenotype. PMID:24859002

  19. Early cysteine-dependent inactivation of 26S proteasomes does not involve particle disassembly

    Directory of Open Access Journals (Sweden)

    Martín Hugo

    2018-06-01

    Full Text Available Under oxidative stress 26S proteasomes suffer reversible disassembly into its 20S and 19S subunits, a process mediated by HSP70. This inhibits the degradation of polyubiquitinated proteins by the 26S proteasome and allows the degradation of oxidized proteins by a free 20S proteasome. Low fluxes of antimycin A-stimulated ROS production caused dimerization of mitochondrial peroxiredoxin 3 and cytosolic peroxiredoxin 2, but not peroxiredoxin overoxidation and overall oxidation of cellular protein thiols. This moderate redox imbalance was sufficient to inhibit the ATP stimulation of 26S proteasome activity. This process was dependent on reversible cysteine oxidation. Moreover, our results show that this early inhibition of ATP stimulation occurs previous to particle disassembly, indicating an intermediate step during the redox regulation of the 26S proteasome with special relevance under redox signaling rather than oxidative stress conditions.

  20. Underwater Nuclear Fuel Disassembly and Rod Storage Process and Equipment Description. Volume II

    International Nuclear Information System (INIS)

    Viebrock, J.M.

    1981-09-01

    The process, equipment, and the demonstration of the Underwater Nuclear Fuel Disassembly and Rod Storage System are presented. The process was shown to be a viable means of increasing spent fuel pool storage density by taking apart fuel assemblies and storing the fuel rods in a denser fashion than in the original storage racks. The assembly's nonfuel-bearing waste is compacted and containerized. The report documents design criteria and analysis, fabrication, demonstration program results, and proposed enhancements to the system

  1. Remote disassembly of radioactively contaminated vessels by means of an arc saw

    International Nuclear Information System (INIS)

    Beitel, G.A.

    1977-01-01

    The arc saw, a newly developed tool, is a toothless circular saw which cuts by means of an electric arc. Cutting speeds between 20 to 30 cm 2 /S and depths up to 45 cm are possible. There is no mechanical contact between blade and work piece, no binding, and no blade breakage. The arc saw will be applied to the rapid and remote disassembly of multiple ton, contaminated stainless steel vessels

  2. What if the hand piece spring disassembles during robotic radical prostatectomy?

    Science.gov (United States)

    Akbulut, Ziya; Canda, Abdullah Erdem; Atmaca, Ali Fuat; Asil, Erem; Isgoren, Egemen; Balbay, Mevlana Derya

    2011-01-01

    Robot-assisted laparoscopic radical prostatectomy (RALRP) is successfully being performed for treating prostate cancer (PCa). However, instrumentation failure associated with robotic procedures represents a unique new problem. We report the successful completion of RALRP in spite of a disassembled hand piece spring during the procedure. A PubMed/Medline search was made concerning robotic malfunction and robot-assisted laparoscopic radical prostatectomy to discuss our experience. We performed RALRP in a 60-year-old male patient with localized PCa. During the procedure, the spring of the hand piece disassembled, and we were not able to reassemble it. We completed the procedure successfully however without fixing the disassembled hand piece spring. We were able to grasp tissue and needles when we brought our fingers together. The only movement we needed to do was to move fingers apart to release tissue or needles caught by robotic instrument. Although malfunction risk related to the da Vinci Surgical System seems to be very low, it might still occur. Sometimes, simple maneuvers may compensate for the failed function as occurred in our case. However, patients should be informed before the operation about the possibility of converting their procedure to laparoscopic or open due to robotic malfunction.

  3. Phosphorylation of p37 is important for Golgi disassembly at mitosis

    International Nuclear Information System (INIS)

    Kaneko, Yayoi; Tamura, Kaori; Totsukawa, Go; Kondo, Hisao

    2010-01-01

    Research highlights: → p37 is phosphorylated on Serine-56 and Threonine-59 by Cdc2 at mitosis. → Phosphorylated p37 does not bind to Golgi membranes. → p37 phosphorylation inhibits p97/p37-mediated Golgi membrane fusion. -- Abstract: In mammals, the Golgi apparatus is disassembled at early mitosis and reassembled at the end of mitosis. For Golgi disassembly, membrane fusion needs to be blocked. Golgi biogenesis requires two distinct p97ATPase-mediated membrane fusion, the p97/p47 and p97/p37 pathways. We previously reported that p47 phosphorylation on Serine-140 by Cdc2 results in mitotic inhibition of the p97/p47 pathway . In this study, we demonstrate that p37 is phosphorylated on Serine-56 and Threonine-59 by Cdc2 at mitosis, and this phosphorylated p37 does not bind to Golgi membranes. Using an in vitro Golgi reassembly assay, we show that mutated p37(S56D, T59D), which mimics mitotic phosphorylation, does not cause any cisternal regrowth, indicating that p37 phosphorylation inhibits the p97/p37 pathway. Our results demonstrate that p37 phosphorylation on Serine-56 and Threonine-59 is important for Golgi disassembly at mitosis.

  4. SAVANNAH RIVER SITE R-REACTOR DISASSEMBLY BASIN IN-SITU DECOMMISSIONING -10499

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Serrato, M.; Blankenship, J.; Griffin, W.

    2010-01-04

    The US DOE concept for facility in-situ decommissioning (ISD) is to physically stabilize and isolate intact, structurally sound facilities that are no longer needed for their original purpose, i.e., generating (reactor facilities), processing(isotope separation facilities) or storing radioactive materials. The 105-R Disassembly Basin is the first SRS reactor facility to undergo the in-situ decommissioning (ISD) process. This ISD process complies with the 105-R Disassembly Basin project strategy as outlined in the Engineering Evaluation/Cost Analysis for the Grouting of the R-Reactor Disassembly Basin at the Savannah River Site and includes: (1) Managing residual water by solidification in-place or evaporation at another facility; (2) Filling the below grade portion of the basin with cementitious materials to physically stabilize the basin and prevent collapse of the final cap - Sludge and debris in the bottom few feet of the basin will be encapsulated between the basin floor and overlying fill material to isolate it from the environment; (3) Demolishing the above grade portion of the structure and relocating the resulting debris to another location or disposing of the debris in-place; and (4) Capping the basin area with a concrete slab which is part of an engineered cap to prevent inadvertent intrusion. The estimated total grout volume to fill the 105-R Reactor Disassembly Basin is 24,384 cubic meters or 31,894 cubic yards. Portland cement-based structural fill materials were designed and tested for the reactor ISD project, and a placement strategy for stabilizing the basin was developed. Based on structural engineering analyses and material flow considerations, maximum lift heights and differential height requirements were determined. Pertinent data and information related to the SRS 105-R Reactor Disassembly Basin in-situ decommissioning include: regulatory documentation, residual water management, area preparation activities, technology needs, fill material

  5. Application of laser processing for disassembly of nuclear power plants

    Science.gov (United States)

    Baranov, Gennady A.; Zinchenko, A. V.; Arutyunyan, R. B.

    1998-12-01

    Provision of safety and drop of ecological risk at salvaging of nuclear submarines (NSM) of Russia Navy Forces represents one of the most actual problems of nowadays. It is necessary to remove from services of Russian Navy Forces 170 - 180 nuclear submarines by 2000. At salvaging of Russian Navy Forces NSM it should be necessary to cut out reactor compartments with more than 150 thousand tons of gross weight and to fragment terminal carcasses of submarines with gross weight of 2 million tons. Taking into account overall dimensions of salvaging objects and Euro-standard requirement on the sizes of carcass fragments, for salvaging of one NSM it is necessary to execute more than 10 km of cuts. Using of conventional methods of gas and plasma cutting of ship constructions and equipment polluted with radioactive oxides and bedding of insulation and paint and varnish materials causes contamination of working zones and environment by a mix of radioactive substances and highly toxic combustion products, nomenclature of which includes up to 50 names. Calculations carried out in the Institute of industrial and Marine Medicine have shown that salvage of just one NSM with using of gas and plasma cutting are accompanied by discharge into an environment of up to 11.5 kg of chromium oxides, up to 22.5 kg of manganese oxides, up to 97 kg of carbon oxides and up to 650 kg of nitrogen oxides. Fragmentation of such equipment by a method of directional explosion or hydraulic jet is problematic because of complexity of treated constructions and necessity to create special protective facilities, which will accumulate a bulk of radioactive and toxic discharges, as a consequence of the explosion and spreaded by shock waves and water deluges. In a number of new technological processes the cutting with using of high-power industrial lasers radiation stands out. As compared with other technological processes, laser cutting has many advantages determined by such unique properties of laser

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

    Science.gov (United States)

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

    2017-09-12

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

  7. Connexin43 hemichannels contributes to the disassembly of cell junctions through modulation of intracellular oxidative status

    Directory of Open Access Journals (Sweden)

    Yuan Chi

    2016-10-01

    Full Text Available Connexin (Cx hemichannels regulate many cellular processes with little information available regarding their mechanisms. Given that many pathological factors that activate hemichannels also disrupts the integrity of cellular junctions, we speculated a potential participation of hemichannels in the regulation of cell junctions. Here we tested this hypothesis. Exposure of renal tubular epithelial cells to Ca2+-free medium led to disassembly of tight and adherens junctions, as indicated by the reduced level of ZO-1 and cadherin, disorganization of F-actin, and severe drop in transepithelial electric resistance. These changes were preceded by an activation of Cx43 hemichannels, as revealed by extracellular efflux of ATP and intracellular influx of Lucifer Yellow. Inhibition of hemichannels with chemical inhibitors or Cx43 siRNA greatly attenuated the disassembly of cell junctions. Further analysis using fetal fibroblasts derived from Cx43 wide-type (Cx43+/+, heterozygous (Cx43+/- and knockout (Cx43-/- littermates showed that Cx43-positive cells (Cx43+/+ exhibited more dramatic changes in cell shape, F-actin, and cadherin in response to Ca2+ depletion, as compared to Cx43-null cells (Cx43-/-. Consistently, these cells had higher level of protein carbonyl modification and phosphorylation, and much stronger activation of P38 and JNK. Hemichannel opening led to extracellular loss of the major antioxidant glutathione (GSH. Supplement of cells with exogenous GSH or inhibition of oxidative sensitive kinases largely prevented the above-mentioned changes. Taken together, our study indicates that Cx43 hemichannels promote the disassembly of cell junctions through regulation of intracellular oxidative status.

  8. The United States pit disassembly and conversion project -- Meeting the MOX fuel specification

    International Nuclear Information System (INIS)

    Nelson, T.O.; James, C.A.; Kolman, D.G.

    1998-01-01

    The US is actively involved in demonstrating the disassembly of nuclear weapons pits to an unclassified form readied for disposition. The MOX option is the most likely path forward for plutonium that originated from nuclear weapon pits. The US demonstration line for pit disassembly and conversion is known as ARIES, the advanced recovery and integrated extraction system. The ARIES demonstration line is being used to gather data in an integrated fashion of the technologies needed for pit disassembly and conversion. These activities include the following modules: pit bisection, hydride-dehydride, oxide conversion, canning, electrolytic decontamination, and nondestructive assay (NDA). Pit bisection swages in a pit in half. Hydride-dehydride converts the pit plutonium metal to an unclassified metal button. To convert the plutonium metal to an oxide the US is investigating a number of options. The primary oxide conversion approach involves variations of combining plutonium hydriding and subsequent oxidation. Another approach is to simply oxidize the metal under controlled conditions-direct metal oxidation (DMO). To remove the gallium from the plutonium oxide, a thermal distillation approach is being used. These pyrochemical approaches will substantially reduce the wastes produced for oxide conversion of weapon plutonium, compared to traditional aqueous processing. The packaging of either the plutonium metal or oxide to long term storage criteria involves the canning and electrolytic decontamination modules. The NDA suite of instruments is then used to assay the material in the containers, which enables international verification without the need to open the containers and repackage them. All of these processes are described

  9. [PHAHs levels in soil samples from the E-waste disassembly sites and their sources allocation].

    Science.gov (United States)

    Zhao, Gao-Feng; Wang, Zi-Jian

    2009-06-15

    Soil samples (each with 3 replicates of - 1 kg, at the top 0-5 cm layer) were collected from each of the e-waste disassembly sites and the control site. Also obtained from each disassembly site were samples (each weighing - 0.2 kg) of cable coating,stuffing powder, and circuit boards chipping. The contents of 23 PBB congeners, 12 PBDE congeners, and 27 PCB congeners in soil and in their potential sources, including e-waste residues, were measured using the GC-MS5975B technique. The highest level of PBBs was found in the cable coating among the three e-waste residues, with a concentration of 35.25 ng x g(-1). The contents of low-brominated PBBs (including monobromobiphenyls and dibromobiphenyls) accounted for 38% of the total PBBs concentration observed in cable coating sample. The highest levels of PBDEs and PBDE209 were found in the stuffing powder for electronic component among the collected e-waste residues, with a concentration of 29.71 and 4.19 x 10(3) ng x g(-1). PBDE153 and PBDE183 were the most predominant PBDE congeners, with their concentration accounting for 43% and 24% of the total PBDEs concentration observed in the stuffing powder sample, respectively. Levels of PCBs in cable coating were the highest in these e-waste residues, with a concentration of 680.02 ngx g(-1). The observed values of the three PHAHs in soils from the disassembly site were considerably higher than their corresponding values observed in the control site (p < 0.05), which indicates that these PHAHs from e-waste is the pollution source of local environment.

  10. Development of disassembly and pin chopping technology for FBR spent fuels

    International Nuclear Information System (INIS)

    Kobayashi, Tsuguyuki; Namba, Takashi; Kawabe, Yukinari; Washiya, Tadahiro

    2008-01-01

    Japan Atomic Power Company (JAPC) and Japan Atomic Energy Agency (JAEA) have been developing fuel disassembly and fuel pin chopping systems for a future Japanese commercial FBR. At first, the wrapper tube is cut by the slit-cut to pull it out, then the fuel pins are cut by the crop-cut at their end-plugs to separate them from the entrance nozzle. The pins are transferred to the magazine of the chopping machine. A series of tests were performed to develop this procedure. As the result of mechanical cutting tests, the CBN wheel was selected. The slit-cut tests were carried out to evaluated the cutting performance of the wheel. The wrapper tube is normally slit-cut in the circumferential direction. One CBN wheel could cut more than 5 fuel assemblies in this direction. The slit-cut in the axial direction is prepared as provision when the tube is difficult to put out. More work is needed to cut 5mm thick PNC-FMS plate in this direction without damaging the pins beneath it. As the result of the crop-cut tests of end-plugs made of ODS steel, the CBN wheel could cut the 61 pin bundle by two strokes. More work is needed to cut the 217 pin bundle. Fuel pin handling tests were performed to transfer them from the disassembly machine to the chopping machine. The Saucer tray was selected to receive the disassembled pins. All the pins were transferred and loaded into a magazine of the chopping machine. Fuel pin loading tests were conducted to optimize the magazine configuration to make the chopping length within 1.0±0.5 cm. In order to decrease the disturbance during chopping, the width of the magazine was adjusted to be 12 cm and installation of a height adjuster is favourable to control the free space above the pins. (author)

  11. KADIS: a program to analyse the disassembly phase of hypothetical accidents in LMFBRs

    International Nuclear Information System (INIS)

    Schmuck, P.; Jacobs, G.; Arnecke, G.

    1977-11-01

    The program KADIS models the disassembly phase during power excursions in LMFBR hypothetical accidents. KADIS is based on point kinetics in the neutronics part and on a 2-dimensional representation of the reactor core in the hydrodynamics part. The core is modeled as an ideal, compressible fluid which is heated up adiabatically during the excursion. KADIS was built up with the help of the VENUS program of Argonne National Laboratory. Several important features were added to the basic VENUS model. Therefore we give first a complete description of the mathematical models used. Secondly we provide the user with the necessary information to handle the input/output of KADIS. (orig.) [de

  12. Engineering scale tests of mechanical disassembly and short stroke shearing systems for FBR fuel assembly

    International Nuclear Information System (INIS)

    Higuchi, Hidetoshi; Kitagaki, Toru; Koizumi, Kenji; Hirano, Hiroyasu; Takeuchi, Masayuki; Washiya, Tadahiro; Kawabe, Yukinari; Kobayashi, Tsuguyuki

    2011-01-01

    Japan Atomic Energy Agency (JAEA) and The Japan Atomic Power Company (JAPC) have been developing an advanced head-end process based on mechanical disassembly and short stroke shearing systems as a part of Fast Reactor Cycle Technology Development (FaCT). Fuel pins for a fast reactor are installed within a hexagonal shaped wrapper tube made of stainless steel. In order to reprocess the fast reactor fuel pins, they must be removed from the wrapper tube and transported to the shearing system without failure. In addition, the advanced aqueous reprocessing process, called 'NEXT' (New Extraction System for TRU Recovery) process requires a solution of the spent fuel with relatively high concentration (500g/L). JAEA and JAPC have developed the mechanical disassembly and the short stroke shearing technology which is expected to make fragmented fuel to satisfy these requirements. This paper reports the results of engineering scale tests on the mechanical disassembly and short stroke shearing systems. These tests were carried out with simulated FBR fuel assembly and removed pins. The mechanical cutting method has been developed to avoid fuel pin failure during disassembly operation. The cutting process is divided into two modes, so called 'slit-cut' for cutting the wrapper tube and 'crop-cut' for the end plug region of the fuel pin bundle. In the slit-cut mode, the depth of cutting was automatically controlled based on the calculated wastage of the cutting tool and deformation of the wrapper tube which had been measured before the cutting. This procedure was confirmed to minimize the fuel pin failure which was hard to prevent in the case of laser cutting. The cutting speed was also controlled automatically by the electric current of the cutting motor to lower the load of the cutting tool. The removed fuel pins were transported to the shearing machine, whose fuel shearing magazine width was set to be narrow to realize the suitable configuration for the short stroke shearing

  13. Nuclear disassembly of the (Pb+Au) system at Elab=29 MeV per nucleon

    International Nuclear Information System (INIS)

    Piasecki, E.; Kordyasz, A.; Bresson, S.; Crema, E.; Galin, J.; Guerreau, D.; Morjean, M.; Paulot, C.; Pouthas, J.; Jastrzebski, J.; Pienkowski, L.; Skulski, W.; Lott, B.; Quednau, B.; Schroder, W.U.; Toeke, J.

    1990-01-01

    Nuclei, with Z up to 82, emitted in the 208 Pb+ 197 Au reaction at E lab =29 MeV per nucleon, have been measured as a function of the associated neutron multiplicity. The data reveal the presence of strong correlations between character of a collision and neutron multiplicity. The trends suggest a disassembly of the nuclear system into a large number of nucleons and small fragments in the events with the highest neutron multiplicity. In such events, approximately one third of the neutrons are released from the system and fragments yields decrease in an exponential fashion with increasing mass

  14. Prey and mound disassembly, manipulation and transport by fire ant collectives

    Science.gov (United States)

    Dutta, Bahnisikha; Monaenkova, Daria; Goodisman, Michael A.; Goldman, Daniel

    Fire ants inhabit subterranean nests covered by a hemispherical mound of soil permeated by narrow ( 1 body length diameter) tunnels. Fire ants can use their mound for long-term food storage [Gayahan &Tschinkel, J. Insect Sci.,2008]. Since mound tunnels are narrow, we expect that in addition to prey manipulation, mound reconfiguration could also be an important aspect of the food storage strategy. Ant colonies collected from wild were allowed to build nests in containers filled with clay soil in the laboratory. These colonies were offered diverse prey embedded with lead markers, including mealworms, crickets and shrimp. Ant-prey-soil interactions on the nest surface were recorded using overhead video and subsurface using x-ray imaging. Individual ants involved in prey storage exhibited three distinct behaviors: prey maneuvering, prey dissection and mound reconfiguration. Small prey (e.g. mealworms) were collectively carried intact into the mound through a tunnel, and then disassembled within the mound. Larger prey (e.g. shrimp) were dismantled into small pieces above the surface and carried to mound tunnels. The bodies of hard medium-sized prey (e.g. crickets) were buried after limb removal and then disassembled and moved into tunnels. Soil reconfiguration occurred in all cases.

  15. Cofilin phosphorylation is elevated after F-actin disassembly induced by Rac1 depletion.

    Science.gov (United States)

    Liu, Linna; Li, Jing; Zhang, Liwang; Zhang, Feng; Zhang, Rong; Chen, Xiang; Brakebusch, Cord; Wang, Zhipeng; Liu, Xinyou

    2015-01-01

    Cytoskeletal reorganization is essential to keratinocyte function. Rac1 regulates cytoskeletal reorganization through signaling pathways such as the cofilin cascade. Cofilin severs actin filaments after activation by dephosphorylation. Rac1 was knocked out in mouse keratinocytes and it was found that actin filaments disassembled. In the epidermis of mice in which Rac1 was knocked out only in keratinocytes, cofilin phosphorylation was aberrantly elevated, corresponding to repression of the phosphatase slingshot1 (SSH1). These effects were independent of the signaling pathways for p21-activated kinase/LIM kinase (Pak/LIMK), protein kinase C, or protein kinase D or generation of reactive oxygen species. Similarly, when actin polymerization was specifically inhibited or Rac1 was knocked down, cofilin phosphorylation was enhanced and SSH1 was repressed. Repression of SSH1 partially blocked actin depolymerization induced by Rac1 depletion. Therefore, aberrant cofilin phosphorylation that induces actin polymerization might be a consequence of actin disassembly induced by the absence of Rac1. © 2015 International Union of Biochemistry and Molecular Biology.

  16. Plastics disassembly versus bulk recycling: engineering design for end-of-life electronics resource recovery.

    Science.gov (United States)

    Rios, Pedro; Stuart, Julie Ann; Grant, Ed

    2003-12-01

    Annual plastic flows through the business and consumer electronics manufacturing supply chain include nearly 3 billion lb of high-value engineering plastics derived from petroleum. The recovery of resource value from this stream presents critical challenges in areas of materials identification and recycling process design that demand new green engineering technologies applied together with life cycle assessment and ecological supply chain analysis to create viable plastics-to-plastics supply cycles. The sustainable recovery of potentially high-value engineering plastics streams requires that recyclers either avoid mixing plastic parts or purify later by separating smaller plastic pieces created in volume reduction (shredding) steps. Identification and separation constitute significant barriers in the plastics-to-plastics recycling value proposition. In the present work, we develop a model that accepts randomly arriving electronic products to study scenarios by which a recycler might identify and separate high-value engineering plastics as well as metals. Using discrete eventsimulation,we compare current mixed plastics recovery with spectrochemical plastic resin identification and subsequent sorting. Our results show that limited disassembly with whole-part identification can produce substantial yields in separated streams of recovered engineering thermoplastics. We find that disassembly with identification does not constitute a bottleneck, but rather, with relatively few workers, can be configured to pull the process and thus decrease maximum staging space requirements.

  17. Stimuli-disassembling gold nanoclusters for diagnosis of early stage oral cancer by optical coherence tomography

    Science.gov (United States)

    Kim, Chang Soo; Ingato, Dominique; Wilder-Smith, Petra; Chen, Zhongping; Kwon, Young Jik

    2018-01-01

    A key design consideration in developing contrast agents is obtaining distinct, multiple signal changes in diseased tissue. Plasmonic gold nanoparticles (Au NPs) have been developed as contrast agents due to their strong surface plasmon resonance (SPR). This study aims to demonstrate that stimuli-responsive plasmonic Au nanoclusters (Au NCs) can be used as a contrast agent for optical coherence tomography (OCT) in detecting early-stage cancer. Au NPs were clustered via acid-cleavable linkers to synthesize Au NCs that disassemble under mildly acidic conditions into individual Au NPs, simultaneously diminishing SPR effect (quantified by scattering intensity) and increasing Brownian motion (quantified by Doppler variance). The acid-triggered morphological and accompanying optico-physical property changes of the acid-disassembling Au NCs were confirmed by TEM, DLS, UV/Vis, and OCT. Stimuli-responsive Au NCs were applied in a hamster check pouch model carrying early-stage squamous carcinoma tissue. The tissue was visualized by OCT imaging, which showed reduced scattering intensity and increased Doppler variance in the dysplastic tissue. This study demonstrates the promise of diagnosing early-stage cancer using molecularly programmable, inorganic nanomaterial-based contrast agents that are capable of generating multiple, stimuli-triggered diagnostic signals in early-stage cancer.[Figure not available: see fulltext.

  18. Assessment of the impacts of spent fuel disassembly alternatives on the Nuclear Waste Isolation System

    International Nuclear Information System (INIS)

    1984-07-01

    The objective of this report was to evaluate four possible alternative methods of preparing and packaging spent fuel assemblies for geologic disposal against the Reference Process of unmodified spent fuel. The four alternative processes were: (1) End fitting removal, (2) Fission gas venting and resealing, (3) Fuel bundle disassembly and close packing of fuel pins, and (4) Fuel shearing and immobilization. Systems analysis was used to develop a basis of comparison of the alternatives. Conceptual processes and facility layouts were devised for each of the alternatives, based on technology deemed feasible for the purpose. Assessments were made of 15 principal attributes from the technical, operational, safety/risk, and economic considerations related to each of the alternatives, including both the surface packaging and underground repository operations. Specific attributes of the alternative processes were evaluated by assigning a number for each that expressed its merit relative to the corresponding attribute of the Reference Process. Each alternative process was then ranked by summing the numbers for attributes in each of the four assessment areas and collectively. Fuel bundle disassembly and close packing of fuel pins was ranked the preferred method of disposal of spent fuel. 63 references, 46 figures, 46 tables

  19. Engineering multifunctional protein nanoparticles by in vitro disassembling and reassembling of heterologous building blocks

    Science.gov (United States)

    Unzueta, Ugutz; Serna, Naroa; Sánchez-García, Laura; Roldán, Mónica; Sánchez-Chardi, Alejandro; Mangues, Ramón; Villaverde, Antonio; Vázquez, Esther

    2017-12-01

    The engineering of protein self-assembling at the nanoscale allows the generation of functional and biocompatible materials, which can be produced by easy biological fabrication. The combination of cationic and histidine-rich stretches in fusion proteins promotes oligomerization as stable protein-only regular nanoparticles that are composed by a moderate number of building blocks. Among other applications, these materials are highly appealing as tools in targeted drug delivery once empowered with peptidic ligands of cell surface receptors. In this context, we have dissected here this simple technological platform regarding the controlled disassembling and reassembling of the composing building blocks. By applying high salt and imidazole in combination, nanoparticles are disassembled in a process that is fully reversible upon removal of the disrupting agents. By taking this approach, we accomplish here the in vitro generation of hybrid nanoparticles formed by heterologous building blocks. This fact demonstrates the capability to generate multifunctional and/or multiparatopic or multispecific materials usable in nanomedical applications.

  20. pH-Sensitive Reversible Programmed Targeting Strategy by the Self-Assembly/Disassembly of Gold Nanoparticles.

    Science.gov (United States)

    Ma, Jinlong; Hu, Zhenpeng; Wang, Wei; Wang, Xinyu; Wu, Qiang; Yuan, Zhi

    2017-05-24

    A reversible programmed targeting strategy could achieve high tumor accumulation due to its long blood circulation time and high cellular internalization. Here, targeting ligand-modified poly(ethylene glycol) (PEG-ligand), dibutylamines (Bu), and pyrrolidinamines (Py) were introduced on the surface of gold nanoparticles (Au NPs) for reversible shielding/deshielding of the targeting ligands by pH-responsive self-assembly. Hydrophobic interaction and steric repulsion are the main driving forces for the self-assembly/disassembly of Au NPs. The precise self-assembly (pH ≥ 7.2) and disassembly (pH ≤ 6.8) of Au NPs with different ligands could be achieved by fine-tuning the modifying molar ratio of Bu and Py (R m ), which followed the formula R m = 1/(-0.0013X 2 + 0.0323X + 1), in which X is the logarithm of the partition coefficient of the targeting ligand. The assembled/disassembled behavior of Au NPs at pH 7.2 and 6.8 was confirmed by transmission electron microscopy and dynamic light scattering. Enzyme-linked immunosorbent assays and cellular uptake studies showed that the ligands could be buried inside the assembly and exposed when disassembled. More importantly, this process was reversible, which provides the possibility of prolonging blood circulation by shielding ligands associated with the NPs that were effused from tumor tissue.

  1. Neuroprotective Effects against POCD by Photobiomodulation: Evidence from Assembly/Disassembly of the Cytoskeleton

    Directory of Open Access Journals (Sweden)

    Ann D. Liebert

    2016-01-01

    Full Text Available Postoperative cognitive dysfunction (POCD is a decline in memory following anaesthesia and surgery in elderly patients. While often reversible, it consumes medical resources, compromises patient well-being, and possibly accelerates progression into Alzheimer's disease. Anesthetics have been implicated in POCD, as has neuroinflammation, as indicated by cytokine inflammatory markers. Photobiomodulation (PBM is an effective treatment for a number of conditions, including inflammation. PBM also has a direct effect on microtubule disassembly in neurons with the formation of small, reversible varicosities, which cause neural blockade and alleviation of pain symptoms. This mimics endogenously formed varicosities that are neuroprotective against damage, toxins, and the formation of larger, destructive varicosities and focal swellings. It is proposed that PBM may be effective as a preconditioning treatment against POCD; similar to the PBM treatment, protective and abscopal effects that have been demonstrated in experimental models of macular degeneration, neurological, and cardiac conditions.

  2. Chain Assembly and Disassembly Processes Differently Affect the Conformational Space of Ubiquitin Chains.

    Science.gov (United States)

    Kniss, Andreas; Schuetz, Denise; Kazemi, Sina; Pluska, Lukas; Spindler, Philipp E; Rogov, Vladimir V; Husnjak, Koraljka; Dikic, Ivan; Güntert, Peter; Sommer, Thomas; Prisner, Thomas F; Dötsch, Volker

    2018-02-06

    Ubiquitination is the most versatile posttranslational modification. The information is encoded by linkage type as well as chain length, which are translated by ubiquitin binding domains into specific signaling events. Chain topology determines the conformational space of a ubiquitin chain and adds an additional regulatory layer to this ubiquitin code. In particular, processes that modify chain length will be affected by chain conformations as they require access to the elongation or cleavage sites. We investigated conformational distributions in the context of chain elongation and disassembly using pulsed electron-electron double resonance spectroscopy in combination with molecular modeling. Analysis of the conformational space of diubiquitin revealed conformational selection or remodeling as mechanisms for chain recognition during elongation or hydrolysis, respectively. Chain elongation to tetraubiquitin increases the sampled conformational space, suggesting that a high intrinsic flexibility of K48-linked chains may contribute to efficient proteasomal degradation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Disassembly Control of Saccharide-Based Amphiphiles Driven by Electrostatic Repulsion.

    Science.gov (United States)

    Yamada, Taihei; Kokado, Kenta; Sada, Kazuki

    2017-03-14

    According to the design of disassembly using electrostatic repulsion, novel amphiphiles consisting of a lipophilic ion part and a hydrophilic saccharide part were synthesized via the facile copper-catalyzed click reaction, and their molecular assemblies in water and chloroform were studied. The amphiphiles exhibited a molecular orientation opposite to that of the conventional amphiphiles in each case. ζ Potential measurements indicated that the lipophilic ion part is exposed outside in chloroform. The size of a solvophobic part in the amphiphiles dominates the size of an assembling structure; that is, in water, these amphiphiles tethering different lengths of the saccharide part exhibited almost identical assembling size, whereas in chloroform, the size depends on the length of the saccharide part in the amphiphiles.

  4. Electrostatic assembly/disassembly of nanoscaled colloidosomes for light-triggered cargo release

    KAUST Repository

    Li, Song

    2015-04-27

    Colloidosome capsules possess the potential for the encapsulation and release of molecular and macromolecular cargos. However, the stabilization of the colloidosome shell usually requires an additional covalent crosslinking which irreversibly seals the capsules, and greatly limits their applications in large-cargos release. Herein we report nanoscaled colloidosomes designed by the electrostatic assembly of organosilica nanoparticles (NPs) with oppositely charged surfaces (rather than covalent bonds), arising from different contents of a bridged nitrophenylene-alkoxysilane [NB; 3-nitro-N-(3-(triethoxysilyl)propyl)-4-(((3-(triethoxysilyl)propyl)-amino)methyl)benzamid] derivative in the silica. The surface charge of the positively charged NPs was reversed by light irradiation because of a photoreaction in the NB moieties, which impacted the electrostatic interactions between NPs and disassembled the colloidosome nanosystems. This design was successfully applied for the encapsulation and light-triggered release of cargos. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Acoustically Triggered Disassembly of Multilayered Polyelectrolyte Thin Films through Gigahertz Resonators for Controlled Drug Release Applications

    Directory of Open Access Journals (Sweden)

    Zhixin Zhang

    2016-11-01

    Full Text Available Controlled drug release has a high priority for the development of modern medicine and biochemistry. To develop a versatile method for controlled release, a miniaturized acoustic gigahertz (GHz resonator is designed and fabricated which can transfer electric supply to mechanical vibrations. By contacting with liquid, the GHz resonator directly excites streaming flows and induces physical shear stress to tear the multilayered polyelectrolyte (PET thin films. Due to the ultra-high working frequency, the shear stress is greatly intensified, which results in a controlled disassembling of the PET thin films. This technique is demonstrated as an effective method to trigger and control the drug release. Both theory analysis and controlled release experiments prove the thin film destruction and the drug release.

  6. Cofilin phosphorylation is elevated after F-actin disassembly induced by Rac1 depletion

    DEFF Research Database (Denmark)

    Liu, Linna; Li, Jing; Zhang, Liwang

    2015-01-01

    Cytoskeletal reorganization is essential to keratinocyte function. Rac1 regulates cytoskeletal reorganization through signaling pathways such as the cofilin cascade. Cofilin severs actin filaments after activation by dephosphorylation. Rac1 was knocked out in mouse keratinocytes and it was found...... that actin filaments disassembled. In the epidermis of mice in which Rac1 was knocked out only in keratinocytes, cofilin phosphorylation was aberrantly elevated, corresponding to repression of the phosphatase slingshot1 (SSH1). These effects were independent of the signaling pathways for p21-activated kinase....../LIM kinase (Pak/LIMK), protein kinase C, or protein kinase D or generation of reactive oxygen species. Similarly, when actin polymerization was specifically inhibited or Rac1 was knocked down, cofilin phosphorylation was enhanced and SSH1 was repressed. Repression of SSH1 partially blocked actin...

  7. Cdk1 and Okadaic Acid-sensitive Phosphatases Control Assembly of Nuclear Pore Complexes in Drosophila EmbryosV⃞

    OpenAIRE

    Onischenko, Evgeny A.; Gubanova, Natalia V.; Kiseleva, Elena V.; Hallberg, Einar

    2005-01-01

    Disassembly and reassembly of the nuclear pore complexes (NPCs) is one of the major events during open mitosis in higher eukaryotes. However, how this process is controlled by the mitotic machinery is not clear. To investigate this we developed a novel in vivo model system based on syncytial Drosophila embryos. We microinjected different mitotic effectors into the embryonic cytoplasm and monitored the dynamics of disassembly/reassembly of NPCs in live embryos using fluorescently labeled wheat...

  8. Protein dynamics of human RPA and RAD51 on ssDNA during assembly and disassembly of the RAD51 filament.

    Science.gov (United States)

    Ma, Chu Jian; Gibb, Bryan; Kwon, YoungHo; Sung, Patrick; Greene, Eric C

    2017-01-25

    Homologous recombination (HR) is a crucial pathway for double-stranded DNA break (DSB) repair. During the early stages of HR, the newly generated DSB ends are processed to yield long single-stranded DNA (ssDNA) overhangs, which are quickly bound by replication protein A (RPA). RPA is then replaced by the DNA recombinase Rad51, which forms extended helical filaments on the ssDNA. The resulting nucleoprotein filament, known as the presynaptic complex, is responsible for pairing the ssDNA with homologous double-stranded DNA (dsDNA), which serves as the template to guide DSB repair. Here, we use single-molecule imaging to visualize the interplay between human RPA (hRPA) and human RAD51 during presynaptic complex assembly and disassembly. We demonstrate that ssDNA-bound hRPA can undergo facilitated exchange, enabling hRPA to undergo rapid exchange between free and ssDNA-bound states only when free hRPA is present in solution. Our results also indicate that the presence of free hRPA inhibits RAD51 filament nucleation, but has a lesser impact upon filament elongation. This finding suggests that hRPA exerts important regulatory influence over RAD51 and may in turn affect the properties of the assembled RAD51 filament. These experiments provide an important basis for further investigations into the regulation of human presynaptic complex assembly. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  9. Disassembly and reassembly of human papillomavirus virus-like particles produces more virion-like antibody reactivity

    Directory of Open Access Journals (Sweden)

    Zhao Qinjian

    2012-02-01

    Full Text Available Abstract Background Human papillomavirus (HPV vaccines based on major capsid protein L1 are licensed in over 100 countries to prevent HPV infections. The yeast-derived recombinant quadrivalent HPV L1 vaccine, GARDASIL(R, has played an important role in reducing cancer and genital warts since its introduction in 2006. The L1 proteins self-assemble into virus-like particles (VLPs. Results VLPs were subjected to post-purification disassembly and reassembly (D/R treatment during bioprocessing to improve VLP immunoreactivity and stability. The post-D/R HPV16 VLPs and their complex with H16.V5 neutralizing antibody Fab fragments were visualized by cryo electron microscopy, showing VLPs densely decorated with antibody. Along with structural improvements, post-D/R VLPs showed markedly higher antigenicity to conformational and neutralizing monoclonal antibodies (mAbs H16.V5, H16.E70 and H263.A2, whereas binding to mAbs recognizing linear epitopes (H16.J4, H16.O7, and H16.H5 was greatly reduced. Strikingly, post-D/R VLPs showed no detectable binding to H16.H5, indicating that the H16.H5 epitope is not accessible in fully assembled VLPs. An atomic homology model of the entire HPV16 VLP was generated based on previously determined high-resolution structures of bovine papillomavirus and HPV16 L1 pentameric capsomeres. Conclusions D/R treatment of HPV16 L1 VLPs produces more homogeneous VLPs with more virion-like antibody reactivity. These effects can be attributed to a combination of more complete and regular assembly of the VLPs, better folding of L1, reduced non-specific disulfide-mediated aggregation and increased stability of the VLPs. Markedly different antigenicity of HPV16 VLPs was observed upon D/R treatment with a panel of monoclonal antibodies targeting neutralization sensitive epitopes. Multiple epitope-specific assays with a panel of mAbs with different properties and epitopes are required to gain a better understanding of the immunochemical

  10. Cdk1 and okadaic acid-sensitive phosphatases control assembly of nuclear pore complexes in Drosophila embryos.

    Science.gov (United States)

    Onischenko, Evgeny A; Gubanova, Natalia V; Kiseleva, Elena V; Hallberg, Einar

    2005-11-01

    Disassembly and reassembly of the nuclear pore complexes (NPCs) is one of the major events during open mitosis in higher eukaryotes. However, how this process is controlled by the mitotic machinery is not clear. To investigate this we developed a novel in vivo model system based on syncytial Drosophila embryos. We microinjected different mitotic effectors into the embryonic cytoplasm and monitored the dynamics of disassembly/reassembly of NPCs in live embryos using fluorescently labeled wheat germ agglutinin (WGA) or in fixed embryos using electron microscopy and immunostaining techniques. We found that in live embryos Cdk1 activity was necessary and sufficient to induce disassembly of NPCs as well as their cytoplasmic mimics: annulate lamellae pore complexes (ALPCs). Cdk1 activity was also required for keeping NPCs and ALPCs disassembled during mitosis. In agreement recombinant Cdk1/cyclin B was able to induce phosphorylation and dissociation of nucleoporins from the NPCs in vitro. Conversely, reassembly of NPCs and ALPCs was dependent on the activity of protein phosphatases, sensitive to okadaic acid (OA). Our findings suggest a model where mitotic disassembly/reassembly of the NPCs is regulated by a dynamic equilibrium of Cdk1 and OA-sensitive phosphatase activities and provide evidence that mitotic phosphorylation mediates disassembly of the NPC.

  11. Characterization of the disassembly and reassembly of the HBV glycoprotein surface antigen, a pliable nanoparticle vaccine platform

    International Nuclear Information System (INIS)

    Gallagher, John R.; Torian, Udana; McCraw, Dustin M.; Harris, Audray K.

    2017-01-01

    While nanoparticle vaccine technology is gaining interest due to the success of vaccines like those for the human papillomavirus that is based on viral capsid nanoparticles, little information is available on the disassembly and reassembly of viral surface glycoprotein-based nanoparticles. One such particle is the hepatitis B virus surface antigen (sAg) that exists as nanoparticles. Here we show, using biochemical analysis coupled with electron microscopy, that sAg nanoparticle disassembly requires both reducing agent to disrupt intermolecular disulfide bonds, and detergent to disrupt hydrophobic interactions that stabilize the nanoparticle. Particles were otherwise resistant to salt and urea, suggesting the driving mechanism of particle formation involves hydrophobic interactions. We reassembled isolated sAg protein into nanoparticles by detergent removal and reassembly resulted in a wider distribution of particle diameters. Knowledge of these driving forces of nanoparticle assembly and stability should facilitate construction of epitope-displaying nanoparticles that can be used as immunogens in vaccines.

  12. [Study on the liver-protective and choleretic effect of zhizi baipi soup and its disassembled prescription].

    Science.gov (United States)

    Xiao, Xu; Zhu, Ji-Xiao; Luo, Guang-Ming; Li, Lei; Zhu, Yu-Ye; Zeng, Jin-Xiang; Wang, Xiao-Yun; Wu, Bo

    2013-07-01

    To investigate the effect of Zhizi Baipi soup and its disassembled prescription on protecting liver and improving choleresis and explore the regularity of Zhizi Baipi soup composition. The model of mouse liver injury induced by carbon tetraehlofide (CCl4) was used to observe the effects of Zhizi Baipi soup and its disassembled prescription by oral adminstration, the bile volume was determinied by common bile duct drainage. Zhizi Baipi soup and each treatment group with gardenia could significantly inhibit the increased serum ATL and AST activities, reduce liver MDA level, and significantly promote the bile flow and bilirubin in bile in normal rats. Zhizi Baipi soup has effects on protecting liver and increasing bile secretion, its monarch drug, gardenia plays an important role in the decoction, the effect of eliminating dampness and heat are mainly ascribed to the synergic effect of gardenia and phellodendron.

  13. The development of underwater remote cutting method for the disassembling of rotary specimen rack KRR-1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D. K.; Jung, K. H.; Lee, K. W.; Oh, W. J. [KAERI, Taejon (Korea, Republic of); Lee, K. Y. [Korea Institute of Industrial Technology, Kwangju (Korea, Republic of)

    2004-07-01

    The Rotary Specimen Racks (RSRs) were highly activated and then classified intermediate level radioactive waste for the decommissioning of KRR-1anel2. The RSR can be treated as low level radioactive waste after removing stainless steel parts. To reduce the volume of intermediate level radioactive waste, underwater cutting is required to separate stainless steel parts from RSR because of high radioactivity. In this study, the automatic remote cutting method was developed to disassemble RSR under water. For automatic remote cutting processes, a CAM (Computer Aided Manufacturing) system is employed. A computer inputs NC (Numerical Control) codes to the controller, which are based on CAM model, and the controller instructs the equipment to process according to NC codes automatically. And the cutting force model was improved to cut RSR stably. The automatic cutting was conducted using imitation of RSR and then it was resulted that the developed automatic cutting method can be safely disassemble stainless steel parts of RSR under water.

  14. Characterization of the disassembly and reassembly of the HBV glycoprotein surface antigen, a pliable nanoparticle vaccine platform

    Energy Technology Data Exchange (ETDEWEB)

    Gallagher, John R.; Torian, Udana; McCraw, Dustin M.; Harris, Audray K., E-mail: harrisau@mail.nih.gov

    2017-02-15

    While nanoparticle vaccine technology is gaining interest due to the success of vaccines like those for the human papillomavirus that is based on viral capsid nanoparticles, little information is available on the disassembly and reassembly of viral surface glycoprotein-based nanoparticles. One such particle is the hepatitis B virus surface antigen (sAg) that exists as nanoparticles. Here we show, using biochemical analysis coupled with electron microscopy, that sAg nanoparticle disassembly requires both reducing agent to disrupt intermolecular disulfide bonds, and detergent to disrupt hydrophobic interactions that stabilize the nanoparticle. Particles were otherwise resistant to salt and urea, suggesting the driving mechanism of particle formation involves hydrophobic interactions. We reassembled isolated sAg protein into nanoparticles by detergent removal and reassembly resulted in a wider distribution of particle diameters. Knowledge of these driving forces of nanoparticle assembly and stability should facilitate construction of epitope-displaying nanoparticles that can be used as immunogens in vaccines.

  15. Spent fuel disassembly hardware and other non-fuel bearing components: characterization, disposal cost estimates, and proposed repository acceptance requirements

    Energy Technology Data Exchange (ETDEWEB)

    Luksic, A.T.; McKee, R.W.; Daling, P.M.; Konzek, G.J.; Ludwick, J.D.; Purcell, W.L.

    1986-10-01

    There are two categories of waste considered in this report. The first is the spent fuel disassembly (SFD) hardware. This consists of the hardware remaining after the fuel pins have been removed from the fuel assembly. This includes end fittings, spacer grids, water rods (BWR) or guide tubes (PWR) as appropriate, and assorted springs, fasteners, etc. The second category is other non-fuel-bearing (NFB) components the DOE has agreed to accept for disposal, such as control rods, fuel channels, etc., under Appendix E of the standard utiltiy contract (10 CFR 961). It is estimated that there will be approximately 150 kg of SFD and NFB waste per average metric ton of uranium (MTU) of spent uranium. PWR fuel accounts for approximately two-thirds of the average spent-fuel mass but only 50 kg of the SFD and NFB waste, with most of that being spent fuel disassembly hardware. BWR fuel accounts for one-third of the average spent-fuel mass and the remaining 100 kg of the waste. The relatively large contribution of waste hardware in BWR fuel, will be non-fuel-bearing components, primarily consisting of the fuel channels. Chapters are devoted to a description of spent fuel disassembly hardware and non-fuel assembly components, characterization of activated components, disposal considerations (regulatory requirements, economic analysis, and projected annual waste quantities), and proposed acceptance requirements for spent fuel disassembly hardware and other non-fuel assembly components at a geologic repository. The economic analysis indicates that there is a large incentive for volume reduction.

  16. Disassembly of Bacterial Biofilms by the Self-Assembled Glycolipids Derived from Renewable Resources.

    Science.gov (United States)

    Prasad, Yadavali Siva; Miryala, Sandeep; Lalitha, Krishnamoorthy; Ranjitha, K; Barbhaiwala, Shehnaz; Sridharan, Vellaisamy; Maheswari, C Uma; Srinandan, C S; Nagarajan, Subbiah

    2017-11-22

    More than 80% of chronic infections of bacteria are caused by biofilms. It is also a long-term survival strategy of the pathogens in a nonhost environment. Several amphiphilic molecules have been used in the past to potentially disrupt biofilms; however, the involvement of multistep synthesis, complicated purification and poor yield still remains a major problem. Herein, we report a facile synthesis of glycolipid based surfactant from renewable feedstocks in good yield. The nature of carbohydrate unit present in glycolipid influence the ring chain tautomerism, which resulted in the existence of either cyclic structure or both cyclic and acyclic structures. Interestingly, these glycolipids self-assemble into gel in highly hydrophobic solvents and vegetable oils, and displayed foam formation in water. The potential application of these self-assembled glycolipids to disrupt preformed biofilm was examined against various pathogens. It was observed that glycolipid 6a disrupts Staphylococcus aureus and Listeria monocytogenes biofilm, while the compound 6c was effective in disassembling uropathogenic E. coli and Salmonella enterica Typhimurium biofilms. Altogether, the supramolecular self-assembled materials, either as gel or as surfactant solution could be potentially used for surface cleansing in hospital environments or the food processing industries to effectively reduce pathogenic biofilms.

  17. Substantiation of the admissable concentration of radionuclides in the utilization of concrete from disassembled reactors

    International Nuclear Information System (INIS)

    Engovatov, I.A.; Mashkovich, V.P.; Morev, M.N.

    1995-01-01

    The complete or partial disassembly of the buildings and systems of a modern nuclear power plant results in the formation of hundreds of thousands of tons of wastes. More than 90% of this mass consists of reinforced concrete. Only a small fraction of these materials is contaminated and/or activated up to high level and must be treated as radioactive wastes that must be buried. For this reason, it is helpful to consider a variant of recycling of some of the wastes and secondary utilization of these wastes in different industrial production processes. In this paper, we analyze the concrete that is freed when a nuclear power plant is decommissioned, and in particular, we examine three scenarios: (1) stockpiling and long-term storage of concrete at an industrial site, (2) highway construction, and (3) industrial building construction. Admissable radionuclide concentrations of several isotopes are tabulated for each scenario, and the results provide the basic information for the development of standards for the utilization of the concrete wastes produced during the decommissioning of nuclear power plants

  18. Analysis of the stress-deformed condition of the disassembly parabolic antenna

    Science.gov (United States)

    Odinets, M. N.; Kaygorodtseva, N. V.; Krysova, I. V.

    2018-01-01

    Active development of satellite communications and computer-aided design systems raises the problem of designing parabolic antennas on a new round of development. The aim of the work was to investigate the influence of the design of the mirror of a parabolic antenna on its endurance under wind load. The research task was an automated analysis of the stress-deformed condition of various designs of computer models of a paraboloid mirror (segmented or holistic) at modeling the exploitation conditions. The peculiarity of the research was that the assembly model of the antenna’s mirror was subjected to rigid connections on the contacting surfaces of the segments and only then the finite element grid was generated. The analysis showed the advantage of the design of the demountable antenna, which consists of cyclic segments, in front of the construction of the holistic antenna. Calculation of the stress-deformed condition of the antennas allows us to conclude that dividing the design of the antenna’s mirror on parabolic and cyclic segments increases it strength and rigidity. In the future, this can be used to minimize the mass of antenna and the dimensions of the disassembled antenna. The presented way of modeling a mirror of a parabolic antenna using to the method of the finite-element analysis can be used in the production of antennas.

  19. Disassembly of actin structures by nanosecond pulsed electric field is a downstream effect of cell swelling.

    Science.gov (United States)

    Pakhomov, Andrei G; Xiao, Shu; Pakhomova, Olga N; Semenov, Iurii; Kuipers, Marjorie A; Ibey, Bennett L

    2014-12-01

    Disruption of the actin cytoskeleton structures was reported as one of the characteristic effects of nanosecond-duration pulsed electric field (nsPEF) in both mammalian and plant cells. We utilized CHO cells that expressed the monomeric fluorescent protein (mApple) tagged to actin to test if nsPEF modifies the cell actin directly or as a consequence of cell membrane permeabilization. A train of four 600-ns pulses at 19.2 kV/cm (2 Hz) caused immediate cell membrane poration manifested by YO-PRO-1 dye uptake, gradual cell rounding and swelling. Concurrently, bright actin features were replaced by dimmer and uniform fluorescence of diffuse actin. To block the nsPEF-induced swelling, the bath buffer was isoosmotically supplemented with an electropore-impermeable solute (sucrose). A similar addition of a smaller, electropore-permeable solute (adonitol) served as a control. We demonstrated that sucrose efficiently blocked disassembly of actin features by nsPEF, whereas adonitol did not. Sucrose also attenuated bleaching of mApple-tagged actin in nsPEF-treated cells (as integrated over the cell volume), although did not fully prevent it. We conclude that disintegration of the actin cytoskeleton was a result of cell swelling, which, in turn, was caused by cell permeabilization by nsPEF and transmembrane diffusion of solutes which led to the osmotic imbalance. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Role of a reducing environment in disassembly of the herpesvirus tegument

    Energy Technology Data Exchange (ETDEWEB)

    Newcomb, William W. [Department of Microbiology Immunology and Cancer Biology, University of Virginia Health System, Box 800734, University of Virginia Health System, 1300 Jefferson Park Ave. Charlottesville, VA 22908 (United States); Jones, Lisa M. [Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130 (United States); Dee, Alexander [Department of Molecular, Microbial and Structural Biology, University of Connecticut Health Center, Farmington, CT 06030 (United States); Chaudhry, Farid [Department of Microbiology Immunology and Cancer Biology, University of Virginia Health System, Box 800734, University of Virginia Health System, 1300 Jefferson Park Ave. Charlottesville, VA 22908 (United States); Brown, Jay C., E-mail: JCB2G@VIRGINIA.EDU [Department of Microbiology Immunology and Cancer Biology, University of Virginia Health System, Box 800734, University of Virginia Health System, 1300 Jefferson Park Ave. Charlottesville, VA 22908 (United States)

    2012-09-15

    Initiation of infection by herpes family viruses involves a step in which most of the virus tegument becomes detached from the capsid. Detachment takes place in the host cell cytosol near the virus entry site and it is followed by dispersal of tegument proteins and disappearance of the tegument as a distinct entity. Here we describe the results of experiments designed to test the idea that the reducing environment of the cytosol may contribute to tegument detachment and disassembly. Non-ionic detergent was used to remove the membrane of purified herpes simplex virus under control and reducing conditions. The effects on the tegument were then examined by SDS-PAGE and electron microscopy. Protein analysis demonstrated that most major tegument proteins were removed under both oxidizing and reducing conditions except for UL49 which required a reducing environment. It is proposed therefore that the reducing conditions in the cytosol are involved in removal of UL49 protein. Electron microscopic analysis revealed that capsids produced under oxidizing conditions contained a coating of protein that was absent in reduced virions and which correlated uniquely with the presence of UL49. This capsid-associated layer is suggested to be the location of UL49 in the extracted virion.

  1. The Effect of Uncertain End-of-Life Product Quality and Consumer Incentives on Partial Disassembly Sequencing in Value Recovery Operations

    OpenAIRE

    Rickli, Jeremy Lewis

    2013-01-01

    This dissertation addresses gaps in the interaction between End-of-Life (EoL) product acquisition systems and disassembly sequencing. The research focuses on two remanufacturing research problems; 1) modeling uncertain EoL product quality, quantity, and timing in regards to EoL product acquisition and disassembly sequencing and 2) designing EoL product acquisition schemes considering EoL product uncertainty. The main research objectives within these areas are; analyzing, predicting, and contr...

  2. Methylation-regulated decommissioning of multimeric PP2A complexes

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Cheng-Guo; Zheng, Aiping; Jiang, Li; Rowse, Michael; Stanevich, Vitali; Chen, Hui; Li, Yitong; Satyshur, Kenneth A.; Johnson, Benjamin; Gu, Ting-Jia; Liu, Zuojia; Xing, Yongna

    2017-12-01

    Dynamic assembly/disassembly of signaling complexes are crucial for cellular functions. Specialized latency and activation chaperones control the biogenesis of protein phosphatase 2A (PP2A) holoenzymes that contain a common scaffold and catalytic subunits and a variable regulatory subunit. Here we show that the butterfly-shaped TIPRL (TOR signaling pathway regulator) makes highly integrative multibranching contacts with the PP2A catalytic subunit, selective for the unmethylated tail and perturbing/inactivating the phosphatase active site. TIPRL also makes unusual wobble contacts with the scaffold subunit, allowing TIPRL, but not the overlapping regulatory subunits, to tolerate disease-associated PP2A mutations, resulting in reduced holoenzyme assembly and enhanced inactivation of mutant PP2A. Strikingly, TIPRL and the latency chaperone, α4, coordinate to disassemble active holoenzymes into latent PP2A, strictly controlled by methylation. Our study reveals a mechanism for methylation-responsive inactivation and holoenzyme disassembly, illustrating the complexity of regulation/signaling, dynamic complex disassembly, and disease mutations in cancer and intellectual disability.

  3. Sodium removal disassembly and examination of the Fermi secondary sodium pump

    International Nuclear Information System (INIS)

    Maffei, H.P.; Funk, C.W.; Ballif, J.L.

    1974-01-01

    The Fermi secondary pump is a centrifugal single stage design. The pump had been operated more than 42,000 hours between 450 and 800 0 F. Sodium was drained from the pump in 1973 and the system was back filled with carbon dioxide. The pump was fabricated for 2.25 Cr-1 Mo Croloy steel. Prior to cleaning the pump was inerted and heated with 150 0 F nitrogen using the pump casing as the containment vessel. The water-vapor-nitrogen process was used in three increasing stages of water concentration. The hydrogen concentration in the discharge line was followed as an indicator of the sodium-water reaction rate. Upon completion of the hydrogen evolution, the pump was rinsed several times with hot water. Six pounds of sodium were removed from the pump during a process cycle of 79 hours including rinsing. The maximum pump temperature recorded was 175 0 F with no variation exceeding 10 0 F. The hydrogen concentration in the effluent provided a very satisfactory index for control of the reaction by adjustment of the water-vapor concentration feed to the system. Rinsing effectiveness was limited by a pool of water in the volute that was not drainable with the available system hook up. Sodium and its compounds were removed from all internal surfaces that could be observed by the first stage of disassembly. All such surfaces were coated with a black deposit. Areas above the sodium liquid level were coated with a vermillion colored oxide. Sodium was found on the (1) threads of the impeller nut lock screw, (2) impeller nut-tapered shaft interface, and (3) vapor deposited sodium was found in the oil seal

  4. Effects of repeated manual disassembly and reassembly on the position stability of various implant-abutment complexes

    OpenAIRE

    Semper, Wiebke

    2010-01-01

    In this experiment the precision of manually repositioned abutments in five implant systems with various implant-abutment interfaces was evaluated. Material und Method Of these five implant systems (Straumann, Astra Tech, Replace Select, Camlog, SteriOss) six angled (0°, 5°, 15°) implants each were fixated in a prefabricated metal block. Three persons with differing experience and knowledge of the hypothesis placed and removed a prefabricated abutment with anti-rotational features ...

  5. Nucleolus disassembly and distribution of segregated nucleolar material in prophase of root-tip meristematic cells in Triticum aestivum L.

    Directory of Open Access Journals (Sweden)

    Wang Jianyue

    2015-01-01

    Full Text Available This paper presents details of the process of nucleolar disassembly, studied by conventional transmission electron microscopy (TEM in wheat root cells. In early prophase, chromatin condensation and irregular nucleolar morphology are observed, with many small particles appearing around the nucleolus. In middle prophase, the nucleolus radiates outwards; in late prophase, the fine structure of the nucleolus disappears and nucleolar material diffuses away. Using “en bloc” silver-staining to distinguish between nucleoli and chromatin, we observed that the dispersed nucleolar material aggregates around the chromatin, forming a sheath-like perichromosomal structure that coats the chromosomes in late prophase.

  6. Control of cell volume in the J774 macrophage by microtubule disassembly and cyclic AMP

    Science.gov (United States)

    Melmed, RN; Karanian, PJ; Berlin, RD

    1981-01-01

    We have explored the possibilities that cell volume is regulated by the status of microtubule assembly and cyclic AMP metabolism and may be coordinated with shape change. Treatment of J774.2 mouse macrophages with colchicine caused rapid microtubule disassembly and was associated with a striking increase (from 15-20 to more than 90 percent) in the proportion of cells with a large protuberance at one pole. This provided a simple experimental system in which shape changes occurred in virtually an entire cell population in suspension. Parallel changes in cell volume could then be quantified by isotope dilution techniques. We found that the shape change caused by colchicine was accompanied by a decrease in cell volume of approximately 20 percent. Nocodozole, but not lumicolchicine, caused identical changes in both cell shape and cell volume. The volume loss was not due to cell lysis nor to inhibition of pinocytosis. The mechanism of volume loss was also examined. Colchicine induced a small but reproducible increase in activity of the ouabain-sensitive Na(+), K(+)-dependent ATPase. However, inhibition of this enzyme/transport system by ouabain did not change cell volume nor did it block the colchicines-induced decrease in volume. One the other hand, SITS (4’acetamido, 4-isothiocyano 2,2’ disulfonic acid stilbene), an inhibitor of anion transport, inhibited the effects of colchicines, thus suggesting a role for an anion transport system in cell volume regulation. Because colchicine is known to activate adenylate cyclase in several systems and because cell shape changes are often induced by hormones that elevate cyclic AMP, we also examined the effects of cyclic AMP on cell volume. Agents that act to increase syclic AMP (cholera toxin, which activates adenylate cyclase; IBMX, and inhibitor of phosphodiesterase; and dibutyryl cyclic AMP) all caused a volume decrease comparable to that of colchicine. To define the effective metabolic pathway, we studied two mutants of J

  7. Characterization of spent fuel disassembly hardware and nonfuel bearing components and their relationship to 10 CFR 61

    International Nuclear Information System (INIS)

    Luksic, A.T.

    1987-02-01

    There are a variety of wastes that will be disposed of by the federal waste management system under the Nuclear Waste Policy Act of 1982. The primary waste form is spent nuclear fuel. Currently, this is in the form of fuel assemblies. If the fuel pins are removed from the fuel assembly, as in consolidation, then the fuel pins and the structural portion of the fuel assembly must be considered as separate waste streams. The structural hardware consists of end fittings, grid spacers, water rods (BWR 8 x 8 only), control rod guide tubes (PWR only) and various nuts, washers, springs, etc. These are referred to as spent fuel disassembly (SFD) hardware. There will also be a number of other components which are defined in Appendix E of 10 CFR 961, the standard utility contract. These are referred to as nonfuel-bearing (NFB) components, and include fuel channels (BWR), control rods, fission chambers, neutron sources, thimble plugs, and other components. This paper characterizes spent fuel disassembly (SFD) hardware, and nonfuel-bearing (NFB) components for the most abundant fuel types. The descriptions and figures given are representative for the items described. Many subvariants exist due to design evaluation, which are not covered. This paper also discusses the relationship of these wastes to 10 CFR 61 waste classification

  8. Spiropyran-Decorated SiO₂-Pt Janus Micromotor: Preparation and Light-Induced Dynamic Self-Assembly and Disassembly.

    Science.gov (United States)

    Zhang, Qilu; Dong, Renfeng; Chang, Xueyi; Ren, Biye; Tong, Zhen

    2015-11-11

    The controlled self-assembly of self-propelled Janus micromotors may give the micromotors some potential applications in many fields. In this work, we design a kind of SiO2-Pt Janus catalytic micromotor functionalized by spiropyran (SP) moieties on the surface of the SiO2 hemisphere. The spiropyran-modified SiO2-Pt Janus micromotor exhibits autonomous self-propulsion in the presence of hydrogen peroxide fuel in N,N-dimethylformamide (DMF)/H2O (1:1 in volume) mixture. We demonstrate that the self-propelled Janus micromotors can dynamically assemble into multiple motors because of the electrostatic attractions and π-π stacking between MC molecules induced by UV light irradiation (λ = 365 nm) and also quickly disassemble into mono motors when the light is switched to green light (λ = 520 nm) for the first time. Furthermore, the assembled Janus motors can move together automatically with different motion patterns propelled by the hydrogen peroxide fuels upon UV irradiation. The work provides a new approach not only to the development of the potential application of Janus motors but also to the fundamental science of reversible self-assembly and disassembly of Janus micromotors.

  9. Technical review of WSRC-TR-93-614 criticality safety evaluation for disassembly basin sand filter

    International Nuclear Information System (INIS)

    Reed, R.L.

    1994-01-01

    The study documented in WSRC-TR-93-614 performed an evaluation of the criticality potential associated with the Disassembly Basin Sand Filter for K and L Areas. The document reviewed incorporated results of calculations documented in the engineering calculation N-CLC-K-00151. Analyses of the contents of disassembly basin sludge has indicated that the sludge contains fissile material in excess of subcritical mass limits as specified in ANSI/ANS standards. Previous studies had determined that the fissile material can not collect into a critical configuration in the basin. Since the sand filter is intended to remove suspended particles from the basin water and could serve as a mechanism to collect the fissile material into a critical configuration, the study examined conditions under which criticality could occur in the sand filter. The study shows that criticality is not considered possible in the sand filter. This review emphasized the technical accuracy and presentation of the evaluation. The evaluation was also examined for the elements required for NCSEs. The review was performed in accordance with the NRTSC technical review requirements and procedures and the E7 Manual technical review requirements. The technical review (per the E7 manual) of the engineering calculation (N-CLC-K-0 1 5 1) was previously performed by this reviewer

  10. New findings on the onset of thermal disassembly in spallation reactions; Nouvelles approches pour l'etude de la multifragmentation thermique dans la spallation

    Energy Technology Data Exchange (ETDEWEB)

    Napolitani, P

    2004-09-15

    Thermal multifragmentation is the process of multi body disassembly of a hot nucleus when the excitation is almost purely thermal i.e. dynamical effects like compression (characteristic of ion-ion collisions at Fermi energy) are negligible. Suited reactions are proton induced collision or ion-ion abrasion at relativistic incident energy. Thus we measured four systems at FRS (Fragment separator, GSI, Darmstadt) in inverse kinematics: Fe{sup 56}+p, Fe{sup 56}+Ti(nat), Xe{sup 136}+p, Xe{sup 136}+Ti(nat) a 1 A*GeV. The inverse kinematics allows to observe all particles without any threshold in energy. This is a great advantage compared to experiments in direct kinematics, because only in inverse kinematics it is possible to obtain complete velocity spectra (without a hole for low velocities) for fully identified isotopes. The complex shape of the velocity spectra allows to identify the different deexcitation channels and it clearly shows the transition from a chaotic-dominated process (Gaussian cloud in velocity space) to a direct Coulomb- (or eventually expansion-) dominated process (shell of a sphere in velocity space). Different possible descriptions of the reaction process are discussed, based either on asymmetric fission or multifragmentation. The resulting physical picture is especially interesting for the Fe{sup 56}+p, and Xe{sup 136}+p systems: proton induced collisions could result in the split of the system in two or more fragments due to a fast break-up process. In this case, the configuration of the break-up partition is very asymmetric. The discussion will be extended to other characteristics, like the restoring of nuclear structure features in the isotopic production and the temperature dependence of the isotopic composition of the residues. (author)

  11. T1R3 homomeric sweet taste receptor regulates adipogenesis through Gαs-mediated microtubules disassembly and Rho activation in 3T3-L1 cells.

    Directory of Open Access Journals (Sweden)

    Yosuke Masubuchi

    Full Text Available We previously reported that 3T3-L1 cells express a functional sweet taste receptor possibly as a T1R3 homomer that is coupled to Gs and negatively regulates adipogenesis by a Gαs-mediated but cAMP-independent mechanism. Here, we show that stimulation of this receptor with sucralose or saccharin induced disassembly of the microtubules in 3T3-L1 preadipocytes, which was attenuated by overexpression of the dominant-negative mutant of Gαs (Gαs-G226A. In contrast, overexpression of the constitutively active mutant of Gαs (Gαs-Q227L as well as treatment with cholera toxin or isoproterenol but not with forskolin caused disassembly of the microtubules. Sweetener-induced microtubule disassembly was accompanied by activation of RhoA and Rho-associated kinase (ROCK. This was attenuated with by knockdown of GEF-H1, a microtubule-localized guanine nucleotide exchange factor for Rho GTPase. Furthermore, overexpression of the dominant-negative mutant of RhoA (RhoA-T19N blocked sweetener-induced dephosphorylation of Akt and repression of PPARγ and C/EBPα in the early phase of adipogenic differentiation. These results suggest that the T1R3 homomeric sweet taste receptor negatively regulates adipogenesis through Gαs-mediated microtubule disassembly and consequent activation of the Rho/ROCK pathway.

  12. Nucleolus disassembly in mitosis and apoptosis: dynamic redistribution of phosphorylated-c-Myc, fibrillarin and Ki-67

    Directory of Open Access Journals (Sweden)

    C Soldani

    2009-06-01

    Full Text Available The nucleolus may undergo disassembly either reversibly during mitosis, or irreversibly in apoptosis, thus allowing the redistribution of the nucleolar proteins.We investigated here by immunocytochemistry the fate of three representative proteins, namely phosphorylated c-Myc, fibrillarin and Ki-67, and found that they behave independently in both processes: they relocate in distinct compartments during mitosis, whereas during apoptosis they may either be cleaved (Ki-67 or be extruded into the cytoplasm with a different kinetics and following an ordered, non chaotic program. The separation of these nucleolar proteins which occurs in early apoptotic nuclei continues also in the cytoplasm, and culminates in the final formation of apoptotic blebs containing different nucleolar proteins: this evidence confirms that the apoptotic bodies may be variable in size, content and surface reactivity, and include heterogeneous aggregates of nuclear proteins and/or nucleic acids.

  13. Role of Melatonin in Cell-Wall Disassembly and Chilling Tolerance in Cold-Stored Peach Fruit.

    Science.gov (United States)

    Cao, Shifeng; Bian, Kun; Shi, Liyu; Chung, Hsiao-Hang; Chen, Wei; Yang, Zhenfeng

    2018-06-06

    Melatonin reportedly increases chilling tolerance in postharvest peach fruit during cold storage, but information on its effects on cell-wall disassembly in chilling-injured peaches is limited. In this study, we investigated the role of cell-wall depolymerization in chilling-tolerance induction in melatonin-treated peaches. Treatment with 100 μM melatonin alleviated chilling symptoms (mealiness) characterized by a decrease in fruit firmness and increase in juice extractability in treated peaches during storage. The loss of neutral sugars, such as arabinose and galactose, in both the 1,2-cyclohexylenedinitrilotetraacetic acid (CDTA)- and Na 2 CO 3 -soluble fractions was observed at 7 days in treated peaches, but the contents increased after 28 days of storage. Atomic-force-microscopy (AFM) analysis revealed that the polysaccharide widths in the CDTA- and Na 2 CO 3 -soluble fractions in the treated fruit were mainly distributed in a shorter range, as compared with those in the control fruit. In addition, the expression profiles of a series of cell-wall-related genes showed that melatonin treatment maintained the balance between transcripts of PpPME and PpPG, which accompany the up-regulation of several other genes involved in cell-wall disassembly. Taken together, our results suggested that the reduced mealiness by melatonin was probably associated with its positive regulation of numerous cell-wall-modifying enzymes and proteins; thus, the depolymerization of the cell-wall polysaccharides in the peaches treated with melatonin was maintained, and the treated fruit could soften gradually during cold storage.

  14. Evidence of the Disassembly of α-Cyclodextrin-octylamine Inclusion Compounds Conjugated to Gold Nanoparticles via Thermal and Photothermal Effects

    Directory of Open Access Journals (Sweden)

    Nataly Silva

    2016-10-01

    Full Text Available Cyclodextrin (CD molecules form inclusion compounds (ICs, generating dimers that are capable of encapsulating molecules derived from long-chain hydrocarbons. The aim of this study is to evaluate the structural changes experienced by ICs in solution with increasing temperatures. For this, a nuclear magnetic resonance (1H-NMR titration was performed to determinate the stoichiometric α-cyclodextrin (α-CD:octylamine (OA 2:1 and binding constant (k = 2.16 M−2 of ICs. Solution samples of α-CD-OA ICs conjugated with gold nanoparticles (AuNPs were prepared, and 1H-NMR spectra at different temperatures were recorded. Comparatively, 1H-NMR spectra of the sample irradiated with a laser with tunable wavelengths, with plasmons of conjugated AuNPs, were recorded. In this work, we present evidence of the disassembly of ICs conjugated with AuNPs. Thermal studies demonstrated that, at 114 °C, there are reversible rearrangements of the host and guests in the ICs in a solid state. Migration movements of the guest molecules from the CD cavity were monitored via temperature-dependent 1H-NMR, and were verified comparing the chemical shifts of octylamine dissolved in deuterated dimethylsulfoxide (DMSO-d6 with the OA molecule included in α-CD dissolved in the same solvent. It was observed that, at 117 °C, OA exited the α-CD cavity. CD IC dimer disassembly was also observed when the sample was irradiated with green laser light.

  15. Disassembling the Classroom--An Ethnographic Approach to the Materiality of Education

    Science.gov (United States)

    Roehl, Tobias

    2012-01-01

    The ethnography of education is challenged by the materiality of the classroom. Ethnographic accounts of school lessons mostly highlight language and interaction and offer no suitable methodology for researching objects and their role in the classroom. Moreover, objects are part of complex and interwoven assemblages involving human actors,…

  16. The pedagogical value of Disassemble/Analyze/Assemble (DAA) activities: Assessing the potential for motivation and transfer

    Science.gov (United States)

    Dalrymple, Odesma Onika

    Undergraduate engineering institutions are currently seeking to improve recruiting practices and to retain engineering majors particularly by addressing what many studies document as a major challenge of poor instruction. There is an undisputed need for instructional practices that motivate students in addition to facilitating the transfer of learning beyond the classroom. Reverse engineering and product dissection, more broadly termed Disassemble/Analyze/Assemble (DAA) activities, have shown potential to address these concerns, based on the reviews of students and professors alike. DAA activities involve the systematic deconstruction of an artifact, the subsequent analysis and possible reconstruction of its components for the purpose of understanding the embodied fundamental concepts, design principles and developmental processes. These activities have been part of regular industry practice for some time; however, the systematic analysis of their benefits for learning and instruction is a relatively recent phenomenon. A number of studies have provided highly descriptive accounts of curricula and possible outcomes of DAA activities; but, relatively few have compared participants doing DAA activities to a control group doing more traditional activities. In this respect, two quasi-experiments were conducted as part of a first-year engineering laboratory, and it was hypothesized that students who engaged in the DAA activity would be more motivated and would demonstrate higher frequencies of transfer than the control. A DAA activity that required students to disassemble a single-use camera and analyze its components to discover how it works was compared to a step-by-step laboratory activity in the first experiment and a lecture method of instruction in the second experiment. In both experiments, over forty percent of the students that engaged in the DAA activity demonstrated the ability to transfer the knowledge gained about the functions of the camera's components and

  17. Fast reactor fuel reprocessing plant D1206: disassembly cave window 4 replacement

    International Nuclear Information System (INIS)

    Sutherland, H.G.; Beckitt, S.; Potts, A.B.

    1996-01-01

    At UKAEA's fast reactor reprocessing plant at Dounreay, the containment glass on the zinc bromide cave viewing window tank failed after 13 years active use. External shielding was fitted and the window tank subsequently drained to make it safe. Fuel cropping operations carried out behind the window were resited to enable cave work to continue whilst a project team made arrangements and plans to replace the damaged window. Because of the complexity of the task and high (alpha, beta, gamma and neutron) radiation levels in excess of 500 Sv/hr a rehearsal facility was built to develop the remote handling techniques to be employed in the task. (UK)

  18. Rough order of magnitude cost estimate for immobilization of 50 MT of plutonium sharing existing facilities at Hanford with pit disassembly and conversion facility: alternative 11

    International Nuclear Information System (INIS)

    DiSabatino, A.

    1998-01-01

    The purpose of this Cost Estimate Report is to identify preliminary capital and operating costs for a facility to immobilize 50 metric tons (nominal) of plutonium as a ceramic in an existing facility at Hanford, the Fuels and Materials Examination Facility (FMEF). The Pit Disassembly and Conversion Facility (PDCF), which is being costed in a separate report by LANL, will also be located in the FMEF in this co-location option

  19. Evaluation of nuclear facility decommissioning projects. Three Mile Island Unit 2 reactor defueling and disassembly. Summary status report. Volume 3

    International Nuclear Information System (INIS)

    Doerge, D.H.; Miller, R.L.; Scotti, K.S.

    1986-05-01

    This document summarizes information relating to the preparations for defueling the Three Mile Island Unit 2 (TMI-2) reactor and disassembly activities being performed concurrently with decontamination of the facility. Data have been collected from activity reports, reactor containment entry records, and other sources and entered in a computerized data sysem which permits extraction/manipulation of specific data which can be used in planning for recovery from a loss of coolant event similar to that experienced at TMI-2 on March 28, 1979. This report contains summaries of man-hours, manpower, and radiation exposures incurred during the period of April 23, 1979 to April 16, 1985, in the completion of activities related to preparation for reactor defueling. Support activities conducted outside of radiation areas are not included within the scope of this report. Computerized reports included in this document are: A chronological summary listing work performed for the period; and summary reports for each major task undertaken in connection with the specific scope of this report. Presented in chronological order for the referenced time period. Manually-assembled table summaries are included for: Labor and exposures by department; and labor and exposures by major activity

  20. Studies and research concerning BNFP design and construction of a spent-fuel disassembly/encapsulation system

    International Nuclear Information System (INIS)

    Dabolt, R.J.

    1981-04-01

    Commercial light water power reactor operation in the United States is developing a cumbersome inventory of spent fuel. Systems for interim storage and handling of this fuel are being developed by the Federal Government and industry. Disassembly and canning of the spent fuel elements is one of these systems. It has the potential to double the storage capacity of a prereprocessing storage facility or to triple the capacity of conventional shipping casks. Prototype equipment and controls required to perform this operation in a dry environment have been primarily designed and fabricated at the Barnwell Nuclear Fuel Plant (BNFP). Ridihalgh, Eggers, and Associates have provided design support and fabrication of the control system. This system is capable of extracting and canning the fuel pins and compacting the nonfuel-bearing components of spent fuel assemblies at processing rates of 10 to 12 assemblies per day. The process also provides the potential for enhanced inspection and assay of spent fuel by reducing the interference encountered from the high gamma fields of the nonfuel bearing hardware

  1. Disassembly of microtubules and inhibition of neurite outgrowth, neuroblastoma cell proliferation, and MAP kinase tyrosine dephosphorylation by dibenzyl trisulphide.

    Science.gov (United States)

    Rösner, H; Williams, L A; Jung, A; Kraus, W

    2001-08-22

    Dibenzyl trisulphide (DTS), a main lipophilic compound in Petiveria alliacea L. (Phytolaccaceae), was identified as one of the active immunomodulatory compounds in extracts of the plant. To learn more about its biological activities and molecular mechanisms, we conducted one-dimensional NMR interaction studies with bovine serum albumin (BSA) and tested DTS and related compounds in two well-established neuronal cell-and-tissue culture systems. We found that DTS preferentially binds to an aromatic region of BSA which is rich in tyrosyl residues. In SH-SY5Y neuroblastoma cells, DTS attenuates the dephosphorylation of tyrosyl residues of MAP kinase (erk1/erk2). In the same neuroblastoma cell line and in Wistar 38 human lung fibroblasts, DTS causes a reversible disassembly of microtubules, but it did not affect actin dynamics. Probably due to the disruption of the microtubule dynamics, DTS also inhibits neuroblastoma cell proliferation and neurite outgrowth from spinal cord explants. Related dibenzyl compounds with none, one, or two sulphur atoms were found to be significantly less effective. These data confirmed that the natural compound DTS has a diverse spectrum of biological properties, including cytostatic and neurotoxic actions in addition to immunomodulatory activities.

  2. 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.

  3. Cesium removal from the fuel storage water at the Savannah River Site R-Building Disassembly Basin using 3M Empore reg-sign-membrane filter technology

    International Nuclear Information System (INIS)

    Oji, L.N.; Thompson, M.C.; Peterson, K.; May, C.; Kafka, T.M.

    1998-01-01

    This report describes results from a seven-day demonstration of the use of 3M Empore membrane filter loaded with ion exchange material (potassium cobalt hexacynoferrate (CoHex)) for cesium uptake from the R-Disassembly Basin at the Savannah River Site. The goal of the demonstration was to evaluate the ability of the Process Absorber Development unit (PADU), a water pre-filtration /CoHex configuration on a skid, to remove cesium from R-Disassembly Basin at a linear processing flow rate of 22.7 liters per minute (1,195.8 liters/minute/m 2 or 29.35 gallons/minute/ft 2 ). Over 210,000 liters (> 55,500 gallons) of R-Disassembly Basin water was processed through the PADU without a cesium breakthrough, that is, the effluent after treatment with CoHex, contained less than detectable amounts of radioactive cesium. Some of the observed advantages of the Empore membrane filter technology over conventional packed column ion exchange systems includes rapid flow rates without channeling effects, low volume secondary waste and fast extraction or rapid kinetics per unit of flow

  4. FaCT phase-I evaluation on the advanced aqueous reprocessing process (2). Development of mechanical disassembly and short stroke shearing systems for FBR fuel reprocessing

    International Nuclear Information System (INIS)

    Takeuchi, Masayuki; Kitagaki, Toru; Higuchi, Hidetoshi; Fukushima, Mineo; Washiya, Tadahiro; Kobayashi, Tsuguyuki

    2011-01-01

    JAEA promotes a development of an advanced head-end process in FaCT project. We selected mechanical cutting method for disassembly process and short stroke method for shearing process. In the FaCT phase-I, the criteria was set for decision about the innovative technology and some fundamental performances of the innovative technology such as precision, speed, durability, operation performance and system concept were discussed by the engineering test and design work. We designed and fabricated an engineering-scale test device for mechanical disassembly and short stroke shearing and have carried out the engineering tests using simulated fuel assemblies. As a part of the engineering test results, the effects of cutting conditions on the durability of cutting tool and cutting stability were discussed. Also, the reduction of magazine width is effective to improve the precision of sheared pin length, and the bundle of simulated fuel pins were successfully sheared to 10 ± 5mm, which is a target for the sheared pin length. The criteria for the mechanical disassembly technology and the short stroke shearing technology were satisfied, so we judged that the development of innovative technologies has worth going on for the next phase in the FaCT project. (author)

  5. Phylogenetic disassembly of species boundaries in a widespread group of Australian skinks (Scincidae: Ctenotus).

    Science.gov (United States)

    Rabosky, Daniel L; Hutchinson, Mark N; Donnellan, Stephen C; Talaba, Amanda L; Lovette, Irby J

    2014-08-01

    Scincid lizards in the genus Ctenotus represent one of Australia's most species-rich vertebrate clades, with more than 100 recognized species. Formal diagnoses of many species have relied on qualitative assessments of adult color pattern, but the validity of many such species has not been tested in a phylogenetic framework. We used mitochondrial and nuclear DNA to perform the first phylogenetic analysis of species in the Ctenotus inornatus group, a complex of at least 11 nominal forms that are distributed widely across the Australian continent. Mitochondrial and nuclear gene phylogenies support the presence of multiple species in the group, but these clades largely fail to match species boundaries as currently defined. Multivariate analyses of color pattern indicate that extreme intraspecific morphological variation in this character has created a significant impediment to understanding taxonomic diversity in the group. Our results suggest that nearly all species in the C. inornatus group require substantial taxonomic revision, and several geographically widespread forms ("C. saxatilis" and "C. robustus") appear to be polyphyletic taxa drawn from phenotypically similar but genetically distinct lineages. We describe one new species and provide redescriptions for three additional species. We synonymize names applied to a number of genetically incoherent or otherwise poorly-defined forms. The results of our study highlight an acute need for population genetic studies of species boundaries in Australian skinks, many of which are recognized by morphological traits that vary greatly within and between populations. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Final Status Survey Report for Corrective Action Unit 117 - Pluto Disassembly Facility, Building 2201, Nevada National Security Site, Nevada

    International Nuclear Information System (INIS)

    Gwin, Jeremy; Frenette, Douglas

    2010-01-01

    This document contains the process knowledge, radiological data and subsequent statistical methodology and analysis to support approval for the radiological release of Corrective Action Unit (CAU) 117 - Pluto Disassembly Facility, Building 2201 located in Area 26 of the Nevada National Security Site (NNSS). Preparations for release of the building began in 2009 and followed the methodology described in the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM). MARSSIM is the DOE approved process for release of Real Property (buildings and landmasses) to a set of established criteria or authorized limits. The pre-approved authorized limits for surface contamination values and corresponding assumptions were established by DOE O 5400.5. The release criteria coincide with the acceptance criteria of the U10C landfill permit. The U10C landfill is the proposed location to dispose of the radiologically non-impacted, or ''clean,'' building rubble following demolition. However, other disposition options that include the building and/or waste remaining at the NNSS may be considered providing that the same release limits apply. The Final Status Survey was designed following MARSSIM guidance by reviewing historical documentation and radiological survey data. Following this review a formal radiological characterization survey was performed in two phases. The characterization revealed multiple areas of residual radioactivity above the release criteria. These locations were remediated (decontaminated) and then the surface activity was verified to be less than the release criteria. Once remediation efforts had been successfully completed, a Final Status Survey Plan (10-015, ''Final Status Survey Plan for Corrective Action Unit 117 - Pluto Disassembly Facility, Building 2201'') was developed and implemented to complete the final step in the MARSSIM process, the Final Status Survey. The Final Status Survey Plan consisted of categorizing each individual room into one

  7. Expert System analysis of non-fuel assembly hardware and spent fuel disassembly hardware: Its generation and recommended disposal

    International Nuclear Information System (INIS)

    Williamson, D.A.

    1991-01-01

    Almost all of the effort being expended on radioactive waste disposal in the United States is being focused on the disposal of spent Nuclear Fuel, with little consideration for other areas that will have to be disposed of in the same facilities. one area of radioactive waste that has not been addressed adequately because it is considered a secondary part of the waste issue is the disposal of the various Non-Fuel Bearing Components of the reactor core. These hardware components fall somewhat arbitrarily into two categories: Non-Fuel Assembly (NFA) hardware and Spent Fuel Disassembly (SFD) hardware. This work provides a detailed examination of the generation and disposal of NFA hardware and SFD hardware by the nuclear utilities of the United States as it relates to the Civilian Radioactive Waste Management Program. All available sources of data on NFA and SFD hardware are analyzed with particular emphasis given to the Characteristics Data Base developed by Oak Ridge National Laboratory and the characterization work performed by Pacific Northwest Laboratories and Rochester Gas ampersand Electric. An Expert System developed as a portion of this work is used to assist in the prediction of quantities of NFA hardware and SFD hardware that will be generated by the United States' utilities. Finally, the hardware waste management practices of the United Kingdom, France, Germany, Sweden, and Japan are studied for possible application to the disposal of domestic hardware wastes. As a result of this work, a general classification scheme for NFA and SFD hardware was developed. Only NFA and SFD hardware constructed of zircaloy and experiencing a burnup of less than 70,000 MWD/MTIHM and PWR control rods constructed of stainless steel are considered Low-Level Waste. All other hardware is classified as Greater-ThanClass-C waste

  8. MgATP hydrolysis destabilizes the interaction between subunit H and yeast V1-ATPase, highlighting H's role in V-ATPase regulation by reversible disassembly.

    Science.gov (United States)

    Sharma, Stuti; Oot, Rebecca A; Wilkens, Stephan

    2018-05-12

    Vacuolar H+-ATPases (V-ATPases; V1Vo-ATPases) are rotary motor proton pumps that acidify intracellular compartments and in some tissues, the extracellular space. V-ATPase is regulated by reversible disassembly into autoinhibited V1-ATPase and Vo proton channel sectors. An important player in V-ATPase regulation is subunit H, which binds at the interface of V1 and Vo. H is required for MgATPase activity in holo V-ATPase, but also for stabilizing the MgADP inhibited state in membrane detached V1. However, how H fulfills these two functions is poorly understood. To characterize the H-V1 interaction and its role in reversible disassembly, we determined binding affinities of full length H and its N-terminal domain (HNT) for an isolated heterodimer of subunits E and G (EG), the N-terminal domain of subunit a (aNT), and V1 lacking subunit H (V1ΔH). Using isothermal titration calorimetry (ITC) and biolayer interferometry (BLI), we show that HNT binds EG with moderate affinity, that full length H binds aNT weakly, and that both H and HNT bind V1ΔH with high affinity. We also found that only one molecule of HNT binds V1ΔH with high affinity, suggesting conformational asymmetry of the three EG heterodimers in V1ΔH. Moreover, MgATP hydrolysis-driven conformational changes in V1 destabilized the interaction of H, or HNT, with V1ΔH, suggesting an interplay between MgADP inhibition and subunit H. Our observation that H binding is affected by MgATP hydrolysis in V1 points to H's role in the mechanism of reversible disassembly. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

  9. Authorized Limits for the Release of a 25 Ton Locomotive, Serial Number 21547, at the Area 25 Engine Maintenance, Assembly, and Disassembly Facility, Nevada Test Site, Nevada

    International Nuclear Information System (INIS)

    Gwin, Jeremy; Frenette, Douglas

    2010-01-01

    This document contains process knowledge and radiological data and analysis to support approval for release of the 25-ton locomotive, Serial Number 21547, at the Area 25 Engine Maintenance, Assembly, and Disassembly (EMAD) Facility, located on the Nevada Test Site (NTS). The 25-ton locomotive is a small, one-of-a-kind locomotive used to move railcars in support of the Nuclear Engine for Rocket Vehicle Application project. This locomotive was identified as having significant historical value by the Nevada State Railroad Museum in Boulder City, Nevada, where it will be used as a display piece. A substantial effort to characterize the radiological conditions of the locomotive was undertaken by the NTS Management and Operations Contractor, National Security Technologies, LLC (NSTec). During this characterization process, seven small areas on the locomotive had contamination levels that exceeded the NTS release criteria (limits consistent with U.S. Department of Energy (DOE) Order DOE O 5400.5, 'Radiation Protection of the Public and the Environment'). The decision was made to perform radiological decontamination of these known accessible impacted areas to further the release process. On February 9, 2010, NSTec personnel completed decontamination of these seven areas to within the NTS release criteria. Although all accessible areas of the locomotive had been successfully decontaminated to within NTS release criteria, it was plausible that inaccessible areas of the locomotive (i.e., those areas on the locomotive where it was not possible to perform radiological surveys) could potentially have contamination above unrestricted release limits. To access the majority of these inaccessible areas, the locomotive would have to be disassembled. A complete disassembly for a full radiological survey could have permanently destroyed parts and would have ruined the historical value of the locomotive. Complete disassembly would also add an unreasonable financial burden for the

  10. Advance on the technology of assembly and disassembly of a head frame with four legs and the machine-assembled head frame

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Youzong; Cao Baozhen [Ministry of Coal Industry (China). Geological Exploration Machinery Factory

    1996-12-31

    According to the meditation of assembling headframes from upper to lower instead of that from lower to upper, the authors created successfully a new type of machine for assembling and disassembling headframes as well as a type of machine-assembled headframe. The new type of headframe not only has the merits of old type of headframe with four legs, but also can keep people away from dangers of working in high space and save the workers much labour. The new technology has good effect on raising productive efficiency. 2 figs.

  11. The CD63-Syntenin-1 Complex Controls Post-Endocytic Trafficking of Oncogenic Human Papillomaviruses.

    Science.gov (United States)

    Gräßel, Linda; Fast, Laura Aline; Scheffer, Konstanze D; Boukhallouk, Fatima; Spoden, Gilles A; Tenzer, Stefan; Boller, Klaus; Bago, Ruzica; Rajesh, Sundaresan; Overduin, Michael; Berditchevski, Fedor; Florin, Luise

    2016-08-31

    Human papillomaviruses enter host cells via a clathrin-independent endocytic pathway involving tetraspanin proteins. However, post-endocytic trafficking required for virus capsid disassembly remains unclear. Here we demonstrate that the early trafficking pathway of internalised HPV particles involves tetraspanin CD63, syntenin-1 and ESCRT-associated adaptor protein ALIX. Following internalisation, viral particles are found in CD63-positive endosomes recruiting syntenin-1, a CD63-interacting adaptor protein. Electron microscopy and immunofluorescence experiments indicate that the CD63-syntenin-1 complex controls delivery of internalised viral particles to multivesicular endosomes. Accordingly, infectivity of high-risk HPV types 16, 18 and 31 as well as disassembly and post-uncoating processing of viral particles was markedly suppressed in CD63 or syntenin-1 depleted cells. Our analyses also present the syntenin-1 interacting protein ALIX as critical for HPV infection and CD63-syntenin-1-ALIX complex formation as a prerequisite for intracellular transport enabling viral capsid disassembly. Thus, our results identify the CD63-syntenin-1-ALIX complex as a key regulatory component in post-endocytic HPV trafficking.

  12. Streamlined Approach for Environmental Restoration Plan for Corrective Action Unit 113: Reactor Maintenance, Assembly, and Disassembly Building Nevada Test Site, Nevada

    International Nuclear Information System (INIS)

    Smith, J. L.

    2001-01-01

    This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the action necessary for the closure in place of Corrective Action Unit (CAU) 113 Area 25 Reactor Maintenance, Assembly, and Disassembly Facility (R-MAD). CAU 113 is currently listed in Appendix III of the Federal Facility Agreement and Consent Order (FFACO) (NDEP, 1996). The CAU is located in Area 25 of the Nevada Test Site (NTS) and consists of Corrective Action Site (CAS) 25-04-01, R-MAD Facility (Figures 1-2). This plan provides the methodology for closure in place of CAU 113. The site contains radiologically impacted and hazardous material. Based on preassessment field work, there is sufficient process knowledge to close in place CAU 113 using the SAFER process. At a future date when funding becomes available, the R-MAD Building (25-3110) will be demolished and inaccessible radiologic waste will be properly disposed in the Area 3 Radiological Waste Management Site (RWMS)

  13. Streamlined Approach for Environmental Restoration Plan for Corrective Action Unit 113: Reactor Maintenance, Assembly, and Disassembly Building Nevada Test Site, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    J. L. Smith

    2001-01-01

    This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the action necessary for the closure in place of Corrective Action Unit (CAU) 113 Area 25 Reactor Maintenance, Assembly, and Disassembly Facility (R-MAD). CAU 113 is currently listed in Appendix III of the Federal Facility Agreement and Consent Order (FFACO) (NDEP, 1996). The CAU is located in Area 25 of the Nevada Test Site (NTS) and consists of Corrective Action Site (CAS) 25-04-01, R-MAD Facility (Figures 1-2). This plan provides the methodology for closure in place of CAU 113. The site contains radiologically impacted and hazardous material. Based on preassessment field work, there is sufficient process knowledge to close in place CAU 113 using the SAFER process. At a future date when funding becomes available, the R-MAD Building (25-3110) will be demolished and inaccessible radiologic waste will be properly disposed in the Area 3 Radiological Waste Management Site (RWMS).

  14. Improvement of the in vivo cellular repopulation of decellularized cardiovascular tissues by a detergent-free, non-proteolytic, actin-disassembling regimen.

    Science.gov (United States)

    Assmann, Alexander; Struß, Marc; Schiffer, Franziska; Heidelberg, Friederike; Munakata, Hiroshi; Timchenko, Elena V; Timchenko, Pavel E; Kaufmann, Tim; Huynh, Khon; Sugimura, Yukiharu; Leidl, Quentin; Pinto, Antonio; Stoldt, Volker R; Lichtenberg, Artur; Akhyari, Payam

    2017-12-01

    Low immunogenicity and high repopulation capacity are crucial determinants for the functional and structural performance of acellular cardiovascular implants. The present study evaluates a detergent-free, non-proteolytic, actin-disassembling regimen (BIO) for decellularization of heart valve and vessel grafts, particularly focusing on their bio-functionality. Rat aortic conduits (rAoC; n = 89) and porcine aortic valve samples (n = 106) are decellularized using detergents (group DET) or the BIO regimen. BIO decellularization results in effective elimination of cellular proteins and significantly improves removal of DNA as compared with group DET, while the extracellular matrix (ECM) structure as well as mechanical properties are preserved. The architecture of rAoC in group BIO allows for improved bio-functionalization with fibronectin (FN) in a standardized rat implantation model: BIO treatment significantly increases speed and amount of autologous medial cellular repopulation in vivo (p < 0.001) and decreases the formation of hyperplastic intima (p < 0.001) as compared with FN-coated DET-decellularized grafts. Moreover, there are no signs of infiltration with inflammatory cells. The present biological, detergent-free, non-proteolytic regimen balances effective decellularization and ECM preservation in cardiovascular grafts, and provides optimized bio-functionality. Additionally, this study implies that the actin-disassembling regimen may be a promising approach for bioengineering of acellular scaffolds from other muscular tissues, as for example myocardium or intestine. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  15. African Swine Fever Virus Undergoes Outer Envelope Disruption, Capsid Disassembly and Inner Envelope Fusion before Core Release from Multivesicular Endosomes.

    Directory of Open Access Journals (Sweden)

    Bruno Hernáez

    2016-04-01

    Full Text Available African swine fever virus (ASFV is a nucleocytoplasmic large DNA virus (NCLDV that causes a highly lethal disease in domestic pigs. As other NCLDVs, the extracellular form of ASFV possesses a multilayered structure consisting of a genome-containing nucleoid successively wrapped by a thick protein core shell, an inner lipid membrane, an icosahedral protein capsid and an outer lipid envelope. This structural complexity suggests an intricate mechanism of internalization in order to deliver the virus genome into the cytoplasm. By using flow cytometry in combination with pharmacological entry inhibitors, as well as fluorescence and electron microscopy approaches, we have dissected the entry and uncoating pathway used by ASFV to infect the macrophage, its natural host cell. We found that purified extracellular ASFV is internalized by both constitutive macropinocytosis and clathrin-mediated endocytosis. Once inside the cell, ASFV particles move from early endosomes or macropinosomes to late, multivesicular endosomes where they become uncoated. Virus uncoating requires acidic pH and involves the disruption of the outer membrane as well as of the protein capsid. As a consequence, the inner viral membrane becomes exposed and fuses with the limiting endosomal membrane to release the viral core into the cytosol. Interestingly, virus fusion is dependent on virus protein pE248R, a transmembrane polypeptide of the inner envelope that shares sequence similarity with some members of the poxviral entry/fusion complex. Collective evidence supports an entry model for ASFV that might also explain the uncoating of other multienveloped icosahedral NCLDVs.

  16. Determination of C0-60 in Cobalt Slugs and Slabs and Radionuclides in Curium Sampler Slugs L-Reactor Disassembly Basin

    International Nuclear Information System (INIS)

    Casella, V.R.

    2004-01-01

    Co-60 was historically produced in the SRS reactors. Cobalt slugs were irradiated in the early 1970s. Post-production, remaining cobalt slugs (including slab form) were consolidated for storage. There are approximately nine hundred cobalt slugs currently stored awaiting final disposition. These slugs had historically incomplete documentation for activity rates; therefore, assaying was required in order to determine their activity levels. Since the gamma dose rate from these slugs is extremely high, the most cost effective way to shield a source of this magnitude from personnel and the radiation detector was to use the basin water in which the slugs are stored as the shield. A sodium iodide gamma detector was placed above a specially designed air collimator assembly, so that slug was at least eight feet from the detector and was shielded by the basin water. Using a sodium iodide detector and multichannel analyzer system and an underwater collimator assembly, Co-60 concentrations we re determined for Disassembly Basin cobalt slugs and slabs and 18 curium sampler slugs. The total activity of all of the assayed slugs summed to 31,783 curies. From the Co-60 concentrations of the curium sampler slugs, the irradiation flux was determined for the known irradiation time. The amounts of Pu-238, 239, 240, 241, 242; Am-241, 243; and Cm-242, 244 produced were then obtained based on the original amount of Pu-239 irradiated

  17. The yeast protein kinase Sch9 adjusts V-ATPase assembly/disassembly to control pH homeostasis and longevity in response to glucose availability.

    Directory of Open Access Journals (Sweden)

    Tobias Wilms

    2017-06-01

    Full Text Available The conserved protein kinase Sch9 is a central player in the nutrient-induced signaling network in yeast, although only few of its direct substrates are known. We now provide evidence that Sch9 controls the vacuolar proton pump (V-ATPase to maintain cellular pH homeostasis and ageing. A synthetic sick phenotype arises when deletion of SCH9 is combined with a dysfunctional V-ATPase, and the lack of Sch9 has a significant impact on cytosolic pH (pHc homeostasis. Sch9 physically interacts with, and influences glucose-dependent assembly/disassembly of the V-ATPase, thereby integrating input from TORC1. Moreover, we show that the role of Sch9 in regulating ageing is tightly connected with V-ATPase activity and vacuolar acidity. As both Sch9 and the V-ATPase are highly conserved in higher eukaryotes, it will be interesting to further clarify their cooperative action on the cellular processes that influence growth and ageing.

  18. HUWE1 Ubiquitylates and Degrades the RAC Activator TIAM1 Promoting Cell-Cell Adhesion Disassembly, Migration, and Invasion

    Directory of Open Access Journals (Sweden)

    Lynsey Vaughan

    2015-01-01

    Full Text Available The E3 ubiquitin ligase HUWE1, deregulated in carcinoma, has been implicated in tumor formation. Here, we uncover a role for HUWE1 in cell migration and invasion through degrading the RAC activator TIAM1, implying an additional function in malignant progression. In MDCKII cells in response to HGF, HUWE1 catalyzes TIAM1 ubiquitylation and degradation predominantly at cell-cell adhesions, facilitating junction disassembly, migration, and invasion. Depleting HUWE1 or mutating the TIAM1 ubiquitylation site prevents TIAM1 degradation, antagonizing scattering, and invasion. Moreover, simultaneous depletion of TIAM1 restores migration and invasion in HUWE1-depleted cells. Significantly, we show that HUWE1 stimulates human lung cancer cell invasion through regulating TIAM1 stability. Finally, we demonstrate that HUWE1 and TIAM1 protein levels are inversely correlated in human lung carcinomas. Thus, we elucidate a critical role for HUWE1 in regulating epithelial cell-cell adhesion and provide additional evidence that ubiquitylation contributes to spatiotemporal control of RAC.

  19. Rab5 GTPase controls chromosome alignment through Lamin disassembly and relocation of the NuMA-like protein Mud to the poles during mitosis

    Science.gov (United States)

    Capalbo, Luisa; D'Avino, Pier Paolo; Archambault, Vincent; Glover, David M.

    2011-01-01

    The small GTPase Rab5 is a conserved regulator of membrane trafficking; it regulates the formation of early endosomes, their transport along microtubules, and the fusion to the target organelles. Although several members of the endocytic pathway were recently implicated in spindle organization, it is unclear whether Rab5 has any role during mitosis. Here, we describe that Rab5 is required for proper chromosome alignment during Drosophila mitoses. We also found that Rab5 associated in vivo with nuclear Lamin and mushroom body defect (Mud), the Drosophila counterpart of nuclear mitotic apparatus protein (NuMA). Consistent with this finding, Rab5 was required for the disassembly of the nuclear envelope at mitotic entry and the accumulation of Mud at the spindle poles. Furthermore, Mud depletion caused chromosome misalignment defects that resembled the defects of Rab5 RNAi cells, and double-knockdown experiments indicated that the two proteins function in a linear pathway. Our results indicate a role for Rab5 in mitosis and reinforce the emerging view of the contributions made by cell membrane dynamics to spindle function. PMID:21987826

  20. Disassembly of an arch bridge deformed due to landslide activity and the replacement of a new bridge in the same site. Jisuberi ni yori henkei shita arch bashi no kaitai to shinbashi no kakekae

    Energy Technology Data Exchange (ETDEWEB)

    Sano, S; Morimoto, C; Tomoda, T; Mizukawa, Y; Onushi, M; Ito, T [Kawasaki Heavy Industries, Ltd., Tokyo (Japan)

    1991-10-20

    This report describes the replacement process of an arch bridge deformed due to landslide activity, selection and contents of the disassembly method, and configuration of the new bridge and its design method. The Ryugu Bridge had been damaged by landslides over an extended period. It was a deck arch bridge having originally a span of 74 meters, but it had shortened by 424 mm due to landslide activity during 14 years since its completion. Then it was decided to be replaced by a new bridge having an adjustable structure to support the movement of its abutments. As disassembly of the deformed arch bridge could be dangerous, the best methodology was studied, and the disassembly was carried out by the cable method. The new bridge had box-girder parts in both side of the main truss, so as to be adjustable to the change of the span length, and the bridge was designed for a working life of 50 years if the bearing supports and expansion joints were reset every 10 years. Concerning the connecting parts between the box-girder and the main truss, appropriateness of the sectional configuration was verified by FEM analysis. 9 refs., 18 figs., 2 tab.

  1. From Centralized Disassembly to Life Cycle Management: Status and Progress of E-waste Treatment System in China

    Science.gov (United States)

    Song, Xiaolong; Yang, Jianxin; Lu, Bin; Yang, Dong

    2017-01-01

    China is now facing e-waste problems from both growing domestic generation and illegal imports. Many stakeholders are involved in the e-waste treatment system due to the complexity of e-waste life cycle. Beginning with the state of the e-waste treatment industry in China, this paper summarizes the latest progress in e-waste management from such aspects as the new edition of the China RoHS Directive, new Treatment List, new funding subsidy standard, and eco-design pilots. Thus, a conceptual model for life cycle management of e-waste is generalized. The operating procedure is to first identify the life cycle stages of the e-waste and extract the important life cycle information. Then, life cycle tools can be used to conduct a systematic analysis to help decide how to maximize the benefits from a series of life cycle engineering processes. Meanwhile, life cycle thinking is applied to improve the legislation relating to e-waste so as to continuously improve the sustainability of the e-waste treatment system. By providing an integrative framework, the life cycle management of e-waste should help to realize sustainable management of e-waste in developing countries.

  2. The Presynaptic v-ATPase Reversibly Disassembles and Thereby Modulates Exocytosis but Is Not Part of the Fusion Machinery

    Directory of Open Access Journals (Sweden)

    Anna Bodzęta

    2017-08-01

    Full Text Available Vacuolar H+-ATPase (v-ATPase is a multi-subunit complex comprising two domains: the cytosolic V1 domain catalyzing ATP hydrolysis and the membranous V0 sector translocating protons across membranes. In addition to proton pumping, a direct function of the V0 proteolipid ring in membrane fusion has been proposed for yeast vacuolar fusion and synaptic vesicle exocytosis in Drosophila. Here, we show in cultured hippocampal neurons that in recycling synaptic vesicles, v-ATPases are only transiently assembled in a pH-dependent fashion during the tightly coupled cycle of exo-endocytosis. Upon locking v-ATPase in an assembled state by saliphenylhalamide, we observed use- and time-dependent release depression for stimuli exceeding release of primed vesicles but no abrogation of exocytosis. Thus, the membranous V0 sector is not part of the exocytotic fusion machinery. Instead, v-ATPase modulates release upstream of docking to favor fusion of fully filled synaptic vesicles.

  3. Secretome profiling of oral squamous cell carcinoma-associated fibroblasts reveals organization and disassembly of extracellular matrix and collagen metabolic process signatures.

    Science.gov (United States)

    Bagordakis, Elizabete; Sawazaki-Calone, Iris; Macedo, Carolina Carneiro Soares; Carnielli, Carolina M; de Oliveira, Carine Ervolino; Rodrigues, Priscila Campioni; Rangel, Ana Lucia C A; Dos Santos, Jean Nunes; Risteli, Juha; Graner, Edgard; Salo, Tuula; Paes Leme, Adriana Franco; Coletta, Ricardo D

    2016-07-01

    An important role has been attributed to cancer-associated fibroblasts (CAFs) in the tumorigenesis of oral squamous cell carcinoma (OSCC), the most common tumor of the oral cavity. Previous studies demonstrated that CAF-secreted molecules promote the proliferation and invasion of OSCC cells, inducing a more aggressive phenotype. In this study, we searched for differences in the secretome of CAFs and normal oral fibroblasts (NOF) using mass spectrometry-based proteomics and biological network analysis. Comparison of the secretome profiles revealed that upregulated proteins involved mainly in extracellular matrix organization and disassembly and collagen metabolism. Among the upregulated proteins were fibronectin type III domain-containing 1 (FNDC1), serpin peptidase inhibitor type 1 (SERPINE1), and stanniocalcin 2 (STC2), the upregulation of which was validated by quantitative PCR and ELISA in an independent set of CAF cell lines. The transition of transforming growth factor beta 1 (TGF-β1)-mediating NOFs into CAFs was accompanied by significant upregulation of FNDC1, SERPINE1, and STC2, confirming the participation of these proteins in the CAF-derived secretome. Type I collagen, the main constituent of the connective tissue, was also associated with several upregulated biological processes. The immunoexpression of type I collagen N-terminal propeptide (PINP) was significantly correlated in vivo with CAFs in the tumor front and was associated with significantly shortened survival of OSCC patients. Presence of CAFs in the tumor stroma was also an independent prognostic factor for OSCC disease-free survival. These results demonstrate the value of secretome profiling for evaluating the role of CAFs in the tumor microenvironment and identify potential novel therapeutic targets such as FNDC1, SERPINE1, and STC2. Furthermore, type I collagen expression by CAFs, represented by PINP levels, may be a prognostic marker of OSCC outcome.

  4. Complexity explained

    CERN Document Server

    Erdi, Peter

    2008-01-01

    This book explains why complex systems research is important in understanding the structure, function and dynamics of complex natural and social phenomena. Readers will learn the basic concepts and methods of complex system research.

  5. Complex chemistry

    International Nuclear Information System (INIS)

    Kim, Bong Gon; Kim, Jae Sang; Kim, Jin Eun; Lee, Boo Yeon

    2006-06-01

    This book introduces complex chemistry with ten chapters, which include development of complex chemistry on history coordination theory and Warner's coordination theory and new development of complex chemistry, nomenclature on complex with conception and define, chemical formula on coordination compound, symbol of stereochemistry, stereo structure and isomerism, electron structure and bond theory on complex, structure of complex like NMR and XAFS, balance and reaction on solution, an organo-metallic chemistry, biology inorganic chemistry, material chemistry of complex, design of complex and calculation chemistry.

  6. 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.

  7. (II) complexes

    African Journals Online (AJOL)

    activities of Schiff base tin (II) complexes. Neelofar1 ... Conclusion: All synthesized Schiff bases and their Tin (II) complexes showed high antimicrobial and ...... Singh HL. Synthesis and characterization of tin (II) complexes of fluorinated Schiff bases derived from amino acids. Spectrochim Acta Part A: Molec Biomolec.

  8. Development of an advanced, continuous mild-gasification process for the production of coproducts. Report for Task 4.8, Decontamination and disassembly of the mild-gasification and char-to-carbon PRUs and disposal of products from testing

    Energy Technology Data Exchange (ETDEWEB)

    Merriam, N.W. [Western Research Inst., Laramie, WY (United States); Jha, Mahesh C. [AMAX Research and Development Center, Golden, CO (United States)

    1991-11-01

    This report contains descriptions of mild-gasification and char-to-carbon process research units (PRUS) used by WRI and AMAX R&D Center to conduct tests under contract AC21-87MC24268. Descriptions of materials produced during those tests are also contained herein. Western Research Institute proposes to dispose of remaining fines and dried coal by combustion and remaining coal liquids by incineration during mid-1992. The mild-gasification PRU will be used for additional tests until 1993, at which time WRI proposes to decontaminate and disassemble the PRU. AMAX R&D Center intends to return the spent char, any remaining feed char, and unusable product carbon to the Eagle Butte Mine near Gillette, Wyoming, from where the coal originally came. The solid products will be added to the mine`s coal product stream. Coal liquids collected from condensers will be concentrated and sent to a local oil and solvent recycling company where the liquids will be burned as fuel. The char-to-carbon PRU will be operated periodically until 1993 when the plant will be decontaminated and disassembled.

  9. Communication complexity and information complexity

    Science.gov (United States)

    Pankratov, Denis

    Information complexity enables the use of information-theoretic tools in communication complexity theory. Prior to the results presented in this thesis, information complexity was mainly used for proving lower bounds and direct-sum theorems in the setting of communication complexity. We present three results that demonstrate new connections between information complexity and communication complexity. In the first contribution we thoroughly study the information complexity of the smallest nontrivial two-party function: the AND function. While computing the communication complexity of AND is trivial, computing its exact information complexity presents a major technical challenge. In overcoming this challenge, we reveal that information complexity gives rise to rich geometrical structures. Our analysis of information complexity relies on new analytic techniques and new characterizations of communication protocols. We also uncover a connection of information complexity to the theory of elliptic partial differential equations. Once we compute the exact information complexity of AND, we can compute exact communication complexity of several related functions on n-bit inputs with some additional technical work. Previous combinatorial and algebraic techniques could only prove bounds of the form theta( n). Interestingly, this level of precision is typical in the area of information theory, so our result demonstrates that this meta-property of precise bounds carries over to information complexity and in certain cases even to communication complexity. Our result does not only strengthen the lower bound on communication complexity of disjointness by making it more exact, but it also shows that information complexity provides the exact upper bound on communication complexity. In fact, this result is more general and applies to a whole class of communication problems. In the second contribution, we use self-reduction methods to prove strong lower bounds on the information

  10. Lysosomal multienzyme complex: pros and cons of working together.

    Science.gov (United States)

    Bonten, Erik J; Annunziata, Ida; d'Azzo, Alessandra

    2014-06-01

    The ubiquitous distribution of lysosomes and their heterogeneous protein composition reflects the versatility of these organelles in maintaining cell homeostasis and their importance in tissue differentiation and remodeling. In lysosomes, the degradation of complex, macromolecular substrates requires the synergistic action of multiple hydrolases that usually work in a stepwise fashion. This catalytic machinery explains the existence of lysosomal enzyme complexes that can be dynamically assembled and disassembled to efficiently and quickly adapt to the pool of substrates to be processed or degraded, adding extra tiers to the regulation of the individual protein components. An example of such a complex is the one composed of three hydrolases that are ubiquitously but differentially expressed: the serine carboxypeptidase, protective protein/cathepsin A (PPCA), the sialidase, neuraminidase-1 (NEU1), and the glycosidase β-galactosidase (β-GAL). Next to this 'core' complex, the existence of sub-complexes, which may contain additional components, and function at the cell surface or extracellularly, suggests as yet unexplored functions of these enzymes. Here we review how studies of basic biological processes in the mouse models of three lysosomal storage disorders, galactosialidosis, sialidosis, and GM1-gangliosidosis, revealed new and unexpected roles for the three respective affected enzymes, Ppca, Neu1, and β-Gal, that go beyond their canonical degradative activities. These findings have broadened our perspective on their functions and may pave the way for the development of new therapies for these lysosomal storage disorders.

  11. Surfactant-free purification of membrane protein complexes from bacteria: application to the staphylococcal penicillin-binding protein complex PBP2/PBP2a

    International Nuclear Information System (INIS)

    Paulin, Sarah; Rosado, Helena; Taylor, Peter W; Jamshad, Mohammed; Dafforn, Timothy R; Garcia-Lara, Jorge; Foster, Simon J; Galley, Nicola F; Roper, David I

    2014-01-01

    Surfactant-mediated removal of proteins from biomembranes invariably results in partial or complete loss of function and disassembly of multi-protein complexes. We determined the capacity of styrene-co-maleic acid (SMA) co-polymer to remove components of the cell division machinery from the membrane of drug-resistant staphylococcal cells. SMA-lipid nanoparticles solubilized FtsZ-PBP2-PBP2a complexes from intact cells, demonstrating the close physical proximity of these proteins within the lipid bilayer. Exposure of bacteria to (-)-epicatechin gallate, a polyphenolic agent that abolishes β-lactam resistance in staphylococci, disrupted the association between PBP2 and PBP2a. Thus, SMA purification provides a means to remove native integral membrane protein assemblages with minimal physical disruption and shows promise as a tool for the interrogation of molecular aspects of bacterial membrane protein structure and function. (paper)

  12. Surfactant-free purification of membrane protein complexes from bacteria: application to the staphylococcal penicillin-binding protein complex PBP2/PBP2a

    Science.gov (United States)

    Paulin, Sarah; Jamshad, Mohammed; Dafforn, Timothy R.; Garcia-Lara, Jorge; Foster, Simon J.; Galley, Nicola F.; Roper, David I.; Rosado, Helena; Taylor, Peter W.

    2014-07-01

    Surfactant-mediated removal of proteins from biomembranes invariably results in partial or complete loss of function and disassembly of multi-protein complexes. We determined the capacity of styrene-co-maleic acid (SMA) co-polymer to remove components of the cell division machinery from the membrane of drug-resistant staphylococcal cells. SMA-lipid nanoparticles solubilized FtsZ-PBP2-PBP2a complexes from intact cells, demonstrating the close physical proximity of these proteins within the lipid bilayer. Exposure of bacteria to (-)-epicatechin gallate, a polyphenolic agent that abolishes β-lactam resistance in staphylococci, disrupted the association between PBP2 and PBP2a. Thus, SMA purification provides a means to remove native integral membrane protein assemblages with minimal physical disruption and shows promise as a tool for the interrogation of molecular aspects of bacterial membrane protein structure and function.

  13. Complexity Plots

    KAUST Repository

    Thiyagalingam, Jeyarajan

    2013-06-01

    In this paper, we present a novel visualization technique for assisting the observation and analysis of algorithmic complexity. In comparison with conventional line graphs, this new technique is not sensitive to the units of measurement, allowing multivariate data series of different physical qualities (e.g., time, space and energy) to be juxtaposed together conveniently and consistently. It supports multivariate visualization as well as uncertainty visualization. It enables users to focus on algorithm categorization by complexity classes, while reducing visual impact caused by constants and algorithmic components that are insignificant to complexity analysis. It provides an effective means for observing the algorithmic complexity of programs with a mixture of algorithms and black-box software through visualization. Through two case studies, we demonstrate the effectiveness of complexity plots in complexity analysis in research, education and application. © 2013 The Author(s) Computer Graphics Forum © 2013 The Eurographics Association and Blackwell Publishing Ltd.

  14. Complexity Theory

    Science.gov (United States)

    Lee, William H K.

    2016-01-01

    A complex system consists of many interacting parts, generates new collective behavior through self organization, and adaptively evolves through time. Many theories have been developed to study complex systems, including chaos, fractals, cellular automata, self organization, stochastic processes, turbulence, and genetic algorithms.

  15. Managing Complexity

    DEFF Research Database (Denmark)

    Maylath, Bruce; Vandepitte, Sonia; Minacori, Patricia

    2013-01-01

    and into French. The complexity of the undertaking proved to be a central element in the students' learning, as the collaboration closely resembles the complexity of international documentation workplaces of language service providers. © Association of Teachers of Technical Writing.......This article discusses the largest and most complex international learning-by-doing project to date- a project involving translation from Danish and Dutch into English and editing into American English alongside a project involving writing, usability testing, and translation from English into Dutch...

  16. Complex variables

    CERN Document Server

    Fisher, Stephen D

    1999-01-01

    The most important topics in the theory and application of complex variables receive a thorough, coherent treatment in this introductory text. Intended for undergraduates or graduate students in science, mathematics, and engineering, this volume features hundreds of solved examples, exercises, and applications designed to foster a complete understanding of complex variables as well as an appreciation of their mathematical beauty and elegance. Prerequisites are minimal; a three-semester course in calculus will suffice to prepare students for discussions of these topics: the complex plane, basic

  17. Conformational changes in the AAA ATPase p97–p47 adaptor complex

    Science.gov (United States)

    Beuron, Fabienne; Dreveny, Ingrid; Yuan, Xuemei; Pye, Valerie E; Mckeown, Ciaran; Briggs, Louise C; Cliff, Matthew J; Kaneko, Yayoi; Wallis, Russell; Isaacson, Rivka L; Ladbury, John E; Matthews, Steve J; Kondo, Hisao; Zhang, Xiaodong; Freemont, Paul S

    2006-01-01

    The AAA+ATPase p97/VCP, helped by adaptor proteins, exerts its essential role in cellular events such as endoplasmic reticulum-associated protein degradation or the reassembly of Golgi, ER and the nuclear envelope after mitosis. Here, we report the three-dimensional cryo-electron microscopy structures at ∼20 Å resolution in two nucleotide states of the endogenous hexameric p97 in complex with a recombinant p47 trimer, one of the major p97 adaptor proteins involved in membrane fusion. Depending on the nucleotide state, we observe the p47 trimer to be in two distinct arrangements on top of the p97 hexamer. By combining the EM data with NMR and other biophysical measurements, we propose a model of ATP-dependent p97(N) domain motions that lead to a rearrangement of p47 domains, which could result in the disassembly of target protein complexes. PMID:16601695

  18. Softball Complex

    Science.gov (United States)

    Ellis, Jim

    1977-01-01

    The Parks and Recreation Department of Montgomery, Alabama, has developed a five-field softball complex as part of a growing community park with facilities for camping, golf, aquatics, tennis, and picnicking. (MJB)

  19. Lecithin Complex

    African Journals Online (AJOL)

    1Department of Food Science and Engineering, Xinyang College of Agriculture and ... Results: The UV and IR spectra of the complex showed an additive effect of polydatin-lecithin, in which .... Monochromatic Cu Ka radiation (wavelength =.

  20. Transformation of the fourth power block of the Chernobyl atomic power station into a ecologically safe system by a dock-caisson technological complex

    International Nuclear Information System (INIS)

    Konyukhov, S.N.; Kokulin, Eh.M.; Kozin, S.Ya.; Kurinnoj, V.N.

    1999-01-01

    The designers of the technical solution do not doubt that it is possible to transform the fourth power block of the Chernobyl APS into an ecologically safe system by help of Dock-Caisson technological complex. Application of the Dock-Caisson allows to make the operations of phases 1 and 2 of the Shelter installation transformation at the same time, i.e. to make the installation stabilization and preparation to radioactive wastes extraction simultaneously. By completion of first two phases the conditions are created for instant beginning of phase 3, i.e. disassembling of the content of the crashed power block

  1. Complex analysis

    CERN Document Server

    Freitag, Eberhard

    2005-01-01

    The guiding principle of this presentation of ``Classical Complex Analysis'' is to proceed as quickly as possible to the central results while using a small number of notions and concepts from other fields. Thus the prerequisites for understanding this book are minimal; only elementary facts of calculus and algebra are required. The first four chapters cover the essential core of complex analysis: - differentiation in C (including elementary facts about conformal mappings) - integration in C (including complex line integrals, Cauchy's Integral Theorem, and the Integral Formulas) - sequences and series of analytic functions, (isolated) singularities, Laurent series, calculus of residues - construction of analytic functions: the gamma function, Weierstrass' Factorization Theorem, Mittag-Leffler Partial Fraction Decomposition, and -as a particular highlight- the Riemann Mapping Theorem, which characterizes the simply connected domains in C. Further topics included are: - the theory of elliptic functions based on...

  2. Subgroup complexes

    CERN Document Server

    Smith, Stephen D

    2011-01-01

    This book is intended as an overview of a research area that combines geometries for groups (such as Tits buildings and generalizations), topological aspects of simplicial complexes from p-subgroups of a group (in the spirit of Brown, Quillen, and Webb), and combinatorics of partially ordered sets. The material is intended to serve as an advanced graduate-level text and partly as a general reference on the research area. The treatment offers optional tracks for the reader interested in buildings, geometries for sporadic simple groups, and G-equivariant equivalences and homology for subgroup complexes.

  3. Complex manifolds

    CERN Document Server

    Morrow, James

    2006-01-01

    This book, a revision and organization of lectures given by Kodaira at Stanford University in 1965-66, is an excellent, well-written introduction to the study of abstract complex (analytic) manifolds-a subject that began in the late 1940's and early 1950's. It is largely self-contained, except for some standard results about elliptic partial differential equations, for which complete references are given. -D. C. Spencer, MathSciNet The book under review is the faithful reprint of the original edition of one of the most influential textbooks in modern complex analysis and geometry. The classic

  4. Malleable machines in transcription regulation: the mediator complex.

    Directory of Open Access Journals (Sweden)

    Agnes Tóth-Petróczy

    2008-12-01

    Full Text Available The Mediator complex provides an interface between gene-specific regulatory proteins and the general transcription machinery including RNA polymerase II (RNAP II. The complex has a modular architecture (Head, Middle, and Tail and cryoelectron microscopy analysis suggested that it undergoes dramatic conformational changes upon interactions with activators and RNAP II. These rearrangements have been proposed to play a role in the assembly of the preinitiation complex and also to contribute to the regulatory mechanism of Mediator. In analogy to many regulatory and transcriptional proteins, we reasoned that Mediator might also utilize intrinsically disordered regions (IDRs to facilitate structural transitions and transmit transcriptional signals. Indeed, a high prevalence of IDRs was found in various subunits of Mediator from both Saccharomyces cerevisiae and Homo sapiens, especially in the Tail and the Middle modules. The level of disorder increases from yeast to man, although in both organisms it significantly exceeds that of multiprotein complexes of a similar size. IDRs can contribute to Mediator's function in three different ways: they can individually serve as target sites for multiple partners having distinctive structures; they can act as malleable linkers connecting globular domains that impart modular functionality on the complex; and they can also facilitate assembly and disassembly of complexes in response to regulatory signals. Short segments of IDRs, termed molecular recognition features (MoRFs distinguished by a high protein-protein interaction propensity, were identified in 16 and 19 subunits of the yeast and human Mediator, respectively. In Saccharomyces cerevisiae, the functional roles of 11 MoRFs have been experimentally verified, and those in the Med8/Med18/Med20 and Med7/Med21 complexes were structurally confirmed. Although the Saccharomyces cerevisiae and Homo sapiens Mediator sequences are only weakly conserved, the

  5. Complex Networks

    CERN Document Server

    Evsukoff, Alexandre; González, Marta

    2013-01-01

    In the last decade we have seen the emergence of a new inter-disciplinary field focusing on the understanding of networks which are dynamic, large, open, and have a structure sometimes called random-biased. The field of Complex Networks is helping us better understand many complex phenomena such as the spread of  deseases, protein interactions, social relationships, to name but a few. Studies in Complex Networks are gaining attention due to some major scientific breakthroughs proposed by network scientists helping us understand and model interactions contained in large datasets. In fact, if we could point to one event leading to the widespread use of complex network analysis is the availability of online databases. Theories of Random Graphs from Erdös and Rényi from the late 1950s led us to believe that most networks had random characteristics. The work on large online datasets told us otherwise. Starting with the work of Barabási and Albert as well as Watts and Strogatz in the late 1990s, we now know th...

  6. Managing Complexity

    Energy Technology Data Exchange (ETDEWEB)

    Chassin, David P.; Posse, Christian; Malard, Joel M.

    2004-08-01

    Physical analogs have shown considerable promise for understanding the behavior of complex adaptive systems, including macroeconomics, biological systems, social networks, and electric power markets. Many of today’s most challenging technical and policy questions can be reduced to a distributed economic control problem. Indeed, economically-based control of large-scale systems is founded on the conjecture that the price-based regulation (e.g., auctions, markets) results in an optimal allocation of resources and emergent optimal system control. This paper explores the state of the art in the use physical analogs for understanding the behavior of some econophysical systems and to deriving stable and robust control strategies for them. In particular we review and discussion applications of some analytic methods based on the thermodynamic metaphor according to which the interplay between system entropy and conservation laws gives rise to intuitive and governing global properties of complex systems that cannot be otherwise understood.

  7. Mto2 multisite phosphorylation inactivates non-spindle microtubule nucleation complexes during mitosis

    Science.gov (United States)

    Borek, Weronika E.; Groocock, Lynda M.; Samejima, Itaru; Zou, Juan; de Lima Alves, Flavia; Rappsilber, Juri; Sawin, Kenneth E.

    2015-01-01

    Microtubule nucleation is highly regulated during the eukaryotic cell cycle, but the underlying molecular mechanisms are largely unknown. During mitosis in fission yeast Schizosaccharomyces pombe, cytoplasmic microtubule nucleation ceases simultaneously with intranuclear mitotic spindle assembly. Cytoplasmic nucleation depends on the Mto1/2 complex, which binds and activates the γ-tubulin complex and also recruits the γ-tubulin complex to both centrosomal (spindle pole body) and non-centrosomal sites. Here we show that the Mto1/2 complex disassembles during mitosis, coincident with hyperphosphorylation of Mto2 protein. By mapping and mutating multiple Mto2 phosphorylation sites, we generate mto2-phosphomutant strains with enhanced Mto1/2 complex stability, interaction with the γ-tubulin complex and microtubule nucleation activity. A mutant with 24 phosphorylation sites mutated to alanine, mto2[24A], retains interphase-like behaviour even in mitotic cells. This provides a molecular-level understanding of how phosphorylation ‘switches off' microtubule nucleation complexes during the cell cycle and, more broadly, illuminates mechanisms regulating non-centrosomal microtubule nucleation. PMID:26243668

  8. Tripartite polyionic complex (PIC) micelles as non-viral vectors for mesenchymal stem cell siRNA transfection.

    Science.gov (United States)

    Raisin, Sophie; Morille, Marie; Bony, Claire; Noël, Danièle; Devoisselle, Jean-Marie; Belamie, Emmanuel

    2017-08-22

    In the context of regenerative medicine, the use of RNA interference mechanisms has already proven its efficiency in targeting specific gene expression with the aim of enhancing, accelerating or, more generally, directing stem cell differentiation. However, achievement of good transfection levels requires the use of a gene vector. For in vivo applications, synthetic vectors are an interesting option to avoid possible issues associated with viral vectors (safety, production costs, etc.). Herein, we report on the design of tripartite polyionic complex micelles as original non-viral polymeric vectors suited for mesenchymal stem cell transfection with siRNA. Three micelle formulations were designed to exhibit pH-triggered disassembly in an acidic pH range comparable to that of endosomes. One formulation was selected as the most promising with the highest siRNA loading capacity while clearly maintaining pH-triggered disassembly properties. A thorough investigation of the internalization pathway of micelles into cells with tagged siRNA was made before showing an efficient inhibition of Runx2 expression in primary bone marrow-derived stem cells. This work evidenced PIC micelles as promising synthetic vectors that allow efficient MSC transfection and control over their behavior, from the perspective of their clinical use.

  9. Complex variables

    CERN Document Server

    Flanigan, Francis J

    2010-01-01

    A caution to mathematics professors: Complex Variables does not follow conventional outlines of course material. One reviewer noting its originality wrote: ""A standard text is often preferred [to a superior text like this] because the professor knows the order of topics and the problems, and doesn't really have to pay attention to the text. He can go to class without preparation."" Not so here-Dr. Flanigan treats this most important field of contemporary mathematics in a most unusual way. While all the material for an advanced undergraduate or first-year graduate course is covered, discussion

  10. Complex dynamics

    CERN Document Server

    Carleson, Lennart

    1993-01-01

    Complex dynamics is today very much a focus of interest. Though several fine expository articles were available, by P. Blanchard and by M. Yu. Lyubich in particular, until recently there was no single source where students could find the material with proofs. For anyone in our position, gathering and organizing the material required a great deal of work going through preprints and papers and in some cases even finding a proof. We hope that the results of our efforts will be of help to others who plan to learn about complex dynamics and perhaps even lecture. Meanwhile books in the field a. re beginning to appear. The Stony Brook course notes of J. Milnor were particularly welcome and useful. Still we hope that our special emphasis on the analytic side will satisfy a need. This book is a revised and expanded version of notes based on lectures of the first author at UCLA over several \\Vinter Quarters, particularly 1986 and 1990. We owe Chris Bishop a great deal of gratitude for supervising the production of cour...

  11. Membranes linked by trans-SNARE complexes require lipids prone to non-bilayer structure for progression to fusion.

    Science.gov (United States)

    Zick, Michael; Stroupe, Christopher; Orr, Amy; Douville, Deborah; Wickner, William T

    2014-01-01

    Like other intracellular fusion events, the homotypic fusion of yeast vacuoles requires a Rab GTPase, a large Rab effector complex, SNARE proteins which can form a 4-helical bundle, and the SNARE disassembly chaperones Sec17p and Sec18p. In addition to these proteins, specific vacuole lipids are required for efficient fusion in vivo and with the purified organelle. Reconstitution of vacuole fusion with all purified components reveals that high SNARE levels can mask the requirement for a complex mixture of vacuole lipids. At lower, more physiological SNARE levels, neutral lipids with small headgroups that tend to form non-bilayer structures (phosphatidylethanolamine, diacylglycerol, and ergosterol) are essential. Membranes without these three lipids can dock and complete trans-SNARE pairing but cannot rearrange their lipids for fusion. DOI: http://dx.doi.org/10.7554/eLife.01879.001.

  12. Cosmic Complexity

    Science.gov (United States)

    Mather, John C.

    2012-01-01

    What explains the extraordinary complexity of the observed universe, on all scales from quarks to the accelerating universe? My favorite explanation (which I certainty did not invent) ls that the fundamental laws of physics produce natural instability, energy flows, and chaos. Some call the result the Life Force, some note that the Earth is a living system itself (Gaia, a "tough bitch" according to Margulis), and some conclude that the observed complexity requires a supernatural explanation (of which we have many). But my dad was a statistician (of dairy cows) and he told me about cells and genes and evolution and chance when I was very small. So a scientist must look for me explanation of how nature's laws and statistics brought us into conscious existence. And how is that seemll"!gly Improbable events are actually happening a!1 the time? Well, the physicists have countless examples of natural instability, in which energy is released to power change from simplicity to complexity. One of the most common to see is that cooling water vapor below the freezing point produces snowflakes, no two alike, and all complex and beautiful. We see it often so we are not amazed. But physlc!sts have observed so many kinds of these changes from one structure to another (we call them phase transitions) that the Nobel Prize in 1992 could be awarded for understanding the mathematics of their common features. Now for a few examples of how the laws of nature produce the instabilities that lead to our own existence. First, the Big Bang (what an insufficient name!) apparently came from an instability, in which the "false vacuum" eventually decayed into the ordinary vacuum we have today, plus the most fundamental particles we know, the quarks and leptons. So the universe as a whole started with an instability. Then, a great expansion and cooling happened, and the loose quarks, finding themselves unstable too, bound themselves together into today's less elementary particles like protons and

  13. Studies of complex fragment emission in heavy ion reactions

    International Nuclear Information System (INIS)

    Charity, R.J.; Sobotka, L.G.

    1991-01-01

    This report discusses the following topics: High energy photon production in a HI collision; the mechanism for the disassembly of excited 16 O projectiles into four alpha particles; the disassembly of excited 28 Si projectiles; large pre-fission multiplicities from temperature; dependent friction and fission barriers; multiplicity correlations; molecular beam induced fusion; dwarf ball and wall; mini wall; and computer and local data acquisition systems

  14. Identification of a novel nuclear localization signal and speckle-targeting sequence of tuftelin-interacting protein 11, a splicing factor involved in spliceosome disassembly

    Energy Technology Data Exchange (ETDEWEB)

    Tannukit, Sissada [Center for Craniofacial Molecular Biology, University of Southern California, 2250 Alcazar Street, CSA Rm103, Los Angeles, CA 90033-1004 (United States); Crabb, Tara L.; Hertel, Klemens J. [Department of Microbiology and Molecular Genetics, University of California Irvine, Irvine, CA 92697-4025 (United States); Wen, Xin [Center for Craniofacial Molecular Biology, University of Southern California, 2250 Alcazar Street, CSA Rm103, Los Angeles, CA 90033-1004 (United States); Jans, David A. [Department of Biochemistry and Molecular Biology, Nuclear Signalling Laboratory, Monash University, Clayton, Victoria 3800 (Australia); Paine, Michael L., E-mail: paine@usc.edu [Center for Craniofacial Molecular Biology, University of Southern California, 2250 Alcazar Street, CSA Rm103, Los Angeles, CA 90033-1004 (United States)

    2009-12-18

    Tuftelin-interacting protein 11 (TFIP11) is a protein component of the spliceosome complex that promotes the release of the lariat-intron during late-stage splicing through a direct recruitment and interaction with DHX15/PRP43. Expression of TFIP11 is essential for cell and organismal survival. TFIP11 contains a G-patch domain, a signature motif of RNA-processing proteins that is responsible for TFIP11-DHX15 interactions. No other functional domains within TFIP11 have been described. TFIP11 is localized to distinct speckled regions within the cell nucleus, although excluded from the nucleolus. In this study sequential C-terminal deletions and mutational analyses have identified two novel protein elements in mouse TFIP11. The first domain covers amino acids 701-706 (VKDKFN) and is an atypical nuclear localization signal (NLS). The second domain is contained within amino acids 711-735 and defines TFIP11's distinct speckled nuclear localization. The identification of a novel TFIP11 nuclear speckle-targeting sequence (TFIP11-STS) suggests that this domain directly interacts with additional spliceosomal components. These data help define the mechanism of nuclear/nuclear speckle localization of the splicing factor TFIP11, with implications for it's function.

  15. E3 ligase Hei10: a multifaceted structure-based signaling molecule with roles within and beyond meiosis

    Science.gov (United States)

    De Muyt, Arnaud; Zhang, Liangran; Piolot, Tristan; Kleckner, Nancy; Espagne, Eric; Zickler, Denise

    2014-01-01

    Human enhancer of invasion-10 (Hei10) mediates meiotic recombination and also plays roles in cell proliferation. Here we explore Hei10’s roles throughout the sexual cycle of the fungus Sordaria with respect to localization and effects of null, RING-binding, and putative cyclin-binding (RXL) domain mutations. Hei10 makes three successive types of foci. Early foci form along synaptonemal complex (SC) central regions. At some of these positions, depending on its RING and RXL domains, Hei10 mediates development and turnover of two sequential types of recombination complexes, each demarked by characteristic amplified Hei10 foci. Integration with ultrastructural data for recombination nodules further reveals that recombination complexes differentiate into three types, one of which corresponds to crossover recombination events during or prior to SC formation. Finally, Hei10 positively and negatively modulates SUMO localization along SCs by its RING and RXL domains, respectively. The presented findings suggest that Hei10 integrates signals from the SC, associated recombination complexes, and the cell cycle to mediate both the development and programmed turnover/evolution of recombination complexes via SUMOylation/ubiquitination. Analogous cell cycle-linked assembly/disassembly switching could underlie localization and roles for Hei10 in centrosome/spindle pole body dynamics and associated nuclear trafficking. We suggest that Hei10 is a unique type of structure-based signal transduction protein. PMID:24831702

  16. Structural insights into the p97-Ufd1-Npl4 complex

    Science.gov (United States)

    Pye, Valerie E.; Beuron, Fabienne; Keetch, Catherine A.; McKeown, Ciaran; Robinson, Carol V.; Meyer, Hemmo H.; Zhang, Xiaodong; Freemont, Paul S.

    2007-01-01

    p97/VCP (Cdc48 in yeast) is an essential and abundant member of the AAA+ family of ATPases and is involved in a number of diverse cellular pathways through interactions with different adaptor proteins. The two most characterized adaptors for p97 are p47 and the Ufd1 (ubiquitin fusion degradation 1)-Npl4 (nuclear protein localization 4) complex. p47 directs p97 to membrane fusion events and has been shown to be involved in protein degradation. The Ufd1-Npl4 complex directs p97 to an essential role in endoplasmic reticulum-associated degradation and an important role in mitotic spindle disassembly postmitosis. Here we describe the structural features of the Ufd1-Npl4 complex and its interaction with p97 with the aid of EM and other biophysical techniques. The Ufd1-Npl4 heterodimer has an elongated bilobed structure that is ≈80 × 30 Å in dimension. One Ufd1-Npl4 heterodimer is shown to interact with one p97 hexamer to form the p97-Ufd1-Npl4 complex. The Ufd1-Npl4 heterodimer emanates from one region on the periphery of the N-D1 plane of the p97 hexamer. Intriguingly, the p97-p47 and the p97-Ufd1-Npl4 complexes are significantly different in stoichiometry, symmetry, and quaternary arrangement, reflecting their specific actions and their ability to interact with additional cofactors that cooperate with p97 in diverse cellular pathways. PMID:17202270

  17. Modulation of chromatin structure by the FACT histone chaperone complex regulates HIV-1 integration.

    Science.gov (United States)

    Matysiak, Julien; Lesbats, Paul; Mauro, Eric; Lapaillerie, Delphine; Dupuy, Jean-William; Lopez, Angelica P; Benleulmi, Mohamed Salah; Calmels, Christina; Andreola, Marie-Line; Ruff, Marc; Llano, Manuel; Delelis, Olivier; Lavigne, Marc; Parissi, Vincent

    2017-07-28

    Insertion of retroviral genome DNA occurs in the chromatin of the host cell. This step is modulated by chromatin structure as nucleosomes compaction was shown to prevent HIV-1 integration and chromatin remodeling has been reported to affect integration efficiency. LEDGF/p75-mediated targeting of the integration complex toward RNA polymerase II (polII) transcribed regions ensures optimal access to dynamic regions that are suitable for integration. Consequently, we have investigated the involvement of polII-associated factors in the regulation of HIV-1 integration. Using a pull down approach coupled with mass spectrometry, we have selected the FACT (FAcilitates Chromatin Transcription) complex as a new potential cofactor of HIV-1 integration. FACT is a histone chaperone complex associated with the polII transcription machinery and recently shown to bind LEDGF/p75. We report here that a tripartite complex can be formed between HIV-1 integrase, LEDGF/p75 and FACT in vitro and in cells. Biochemical analyzes show that FACT-dependent nucleosome disassembly promotes HIV-1 integration into chromatinized templates, and generates highly favored nucleosomal structures in vitro. This effect was found to be amplified by LEDGF/p75. Promotion of this FACT-mediated chromatin remodeling in cells both increases chromatin accessibility and stimulates HIV-1 infectivity and integration. Altogether, our data indicate that FACT regulates HIV-1 integration by inducing local nucleosomes dissociation that modulates the functional association between the incoming intasome and the targeted nucleosome.

  18. Phosphomimetic mutation of the mitotically phosphorylated serine 1880 compromises the interaction of the transmembrane nucleoporin gp210 with the nuclear pore complex

    International Nuclear Information System (INIS)

    Onischenko, Evgeny A.; Crafoord, Ellinor; Hallberg, Einar

    2007-01-01

    The nuclear pore complexes (NPCs) reversibly disassemble and reassemble during mitosis. Disassembly of the NPC is accompanied by phosphorylation of many nucleoporins although the function of this is not clear. It was previously shown that in the transmembrane nucleoporin gp210 a single serine residue at position 1880 is specifically phosphorylated during mitosis. Using amino acid substitution combined with live cell imaging, time-lapse microscopy and FRAP, we investigated the role of serine 1880 in binding of gp210 to the NPC in vivo. An alanine substitution mutant (S1880A) was significantly more dynamic at the NPC compared to the wild-type protein, suggesting that serine 1880 is important for binding of gp210 to the NPC. Moreover a glutamate substitution (S1880E) closely mimicking phosphorylated serine specifically interfered with incorporation of gp210 into the NPC and compromised its post-mitotic recruitment to the nuclear envelope of daughter nuclei. Our findings are consistent with the idea that mitotic phosphorylation acts to dissociate gp210 from the structural elements of the NPC

  19. Disassembling archeology, reassembling the modern world.

    Science.gov (United States)

    Carruthers, William; Van Damme, Stéphane

    2017-09-01

    This article provides a substantive discussion of the relevance of the history of archeology to the history of science. At the same time, the article introduces the papers contained in this special issue as exemplars of this relevance. To make its case, the article moves through various themes in the history of archeology that overlap with key issues in the history of science. The article discusses the role and tension of regimes of science in antiquarian and archeological practices, and also considers issues of scale and place, particularly in relation to the field. Additionally, the piece attends to issues of professionalization and the constitution of an archeological public, at the same time as discussing issues of empire, colonialism, and the circulation of knowledge. Meanwhile, enriching discussions within and beyond the history of science, the article discusses the history of archeology and its relationship with museums, collecting, and material culture and materiality. Finally, the piece discusses the relationship of the history of archeology with wider discussions about scientific ethics. In conclusion, the article questions whether we should speak of 'the history of archeology' at all.

  20. Complex analysis and geometry

    CERN Document Server

    Silva, Alessandro

    1993-01-01

    The papers in this wide-ranging collection report on the results of investigations from a number of linked disciplines, including complex algebraic geometry, complex analytic geometry of manifolds and spaces, and complex differential geometry.

  1. Complex Systems: An Introduction

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 9. Complex Systems: An Introduction - Anthropic Principle, Terrestrial Complexity, Complex Materials. V K Wadhawan. General Article Volume 14 Issue 9 September 2009 pp 894-906 ...

  2. Complex differential geometry

    CERN Document Server

    Zheng, Fangyang

    2002-01-01

    The theory of complex manifolds overlaps with several branches of mathematics, including differential geometry, algebraic geometry, several complex variables, global analysis, topology, algebraic number theory, and mathematical physics. Complex manifolds provide a rich class of geometric objects, for example the (common) zero locus of any generic set of complex polynomials is always a complex manifold. Yet complex manifolds behave differently than generic smooth manifolds; they are more coherent and fragile. The rich yet restrictive character of complex manifolds makes them a special and interesting object of study. This book is a self-contained graduate textbook that discusses the differential geometric aspects of complex manifolds. The first part contains standard materials from general topology, differentiable manifolds, and basic Riemannian geometry. The second part discusses complex manifolds and analytic varieties, sheaves and holomorphic vector bundles, and gives a brief account of the surface classifi...

  3. Complex and symplectic geometry

    CERN Document Server

    Medori, Costantino; Tomassini, Adriano

    2017-01-01

    This book arises from the INdAM Meeting "Complex and Symplectic Geometry", which was held in Cortona in June 2016. Several leading specialists, including young researchers, in the field of complex and symplectic geometry, present the state of the art of their research on topics such as the cohomology of complex manifolds; analytic techniques in Kähler and non-Kähler geometry; almost-complex and symplectic structures; special structures on complex manifolds; and deformations of complex objects. The work is intended for researchers in these areas.

  4. Complexity of rice Hsp100 gene family: lessons from rice genome ...

    Indian Academy of Sciences (India)

    Madhu Sudhan

    2007-03-29

    Mar 29, 2007 ... Chaperonins are a class of molecular chaperones found in prokaryotes and in the ... Keywords. Chaperone, gene family, Hsp100, Oryza sativa ..... Sculpting the proteome with AAA+ proteases and disassembly machines; Cell ...

  5. Oligocyclopentadienyl transition metal complexes

    Energy Technology Data Exchange (ETDEWEB)

    de Azevedo, Cristina G.; Vollhardt, K. Peter C.

    2002-01-18

    Synthesis, characterization, and reactivity studies of oligocyclopentadienyl transition metal complexes, namely those of fulvalene, tercyclopentadienyl, quatercyclopentadienyl, and pentacyclopentadienyl(cyclopentadienyl) are the subject of this account. Thermal-, photo-, and redox chemistries of homo- and heteropolynuclear complexes are described.

  6. Photocytotoxic lanthanide complexes

    Indian Academy of Sciences (India)

    Among many applications of lanthanides, gadolinium complexes are used as magnetic resonance imaging (MRI) contrast agents in clinical radiology and luminescent lanthanides for bioanalysis, imaging and sensing. The chemistry of photoactive lanthanide complexes showing biological applications is of recent origin.

  7. ComplexRec 2017

    DEFF Research Database (Denmark)

    a single step in the user's more complex background need. These background needs can often place a variety of constraints on which recommendations are interesting to the user and when they are appropriate. However, relatively little research has been done on these complex recommendation scenarios....... The ComplexRec 2017 workshop addressed this by providing an interactive venue for discussing approaches to recommendation in complex scenarios that have no simple one-size-fits-all-solution....

  8. Complex Correspondence Principle

    International Nuclear Information System (INIS)

    Bender, Carl M.; Meisinger, Peter N.; Hook, Daniel W.; Wang Qinghai

    2010-01-01

    Quantum mechanics and classical mechanics are distinctly different theories, but the correspondence principle states that quantum particles behave classically in the limit of high quantum number. In recent years much research has been done on extending both quantum and classical mechanics into the complex domain. These complex extensions continue to exhibit a correspondence, and this correspondence becomes more pronounced in the complex domain. The association between complex quantum mechanics and complex classical mechanics is subtle and demonstrating this relationship requires the use of asymptotics beyond all orders.

  9. Uranium thiolate complexes

    International Nuclear Information System (INIS)

    Leverd, Pascal C.

    1994-01-01

    This research thesis proposes a new approach to the chemistry of uranium thiolate complexes as these compounds are very promising for various uses (in bio-inorganic chemistry, in some industrial processes like oil desulphurization). It more particularly addresses the U-S bond or more generally bonds between polarizable materials and hard metals. The author thus reports the study of uranium organometallic thiolates (tricyclo-penta-dienic and mono-cyclo-octa-tetraenylic complexes), and of uranium homoleptic thiolates (tetra-thiolate complexes, hexa-thiolate complexes, reactivity of homoleptic thiolate complexes) [fr

  10. Simplicial complexes of graphs

    CERN Document Server

    Jonsson, Jakob

    2008-01-01

    A graph complex is a finite family of graphs closed under deletion of edges. Graph complexes show up naturally in many different areas of mathematics, including commutative algebra, geometry, and knot theory. Identifying each graph with its edge set, one may view a graph complex as a simplicial complex and hence interpret it as a geometric object. This volume examines topological properties of graph complexes, focusing on homotopy type and homology. Many of the proofs are based on Robin Forman's discrete version of Morse theory. As a byproduct, this volume also provides a loosely defined toolbox for attacking problems in topological combinatorics via discrete Morse theory. In terms of simplicity and power, arguably the most efficient tool is Forman's divide and conquer approach via decision trees; it is successfully applied to a large number of graph and digraph complexes.

  11. On Complex Random Variables

    Directory of Open Access Journals (Sweden)

    Anwer Khurshid

    2012-07-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE In this paper, it is shown that a complex multivariate random variable  is a complex multivariate normal random variable of dimensionality if and only if all nondegenerate complex linear combinations of  have a complex univariate normal distribution. The characteristic function of  has been derived, and simpler forms of some theorems have been given using this characterization theorem without assuming that the variance-covariance matrix of the vector  is Hermitian positive definite. Marginal distributions of  have been given. In addition, a complex multivariate t-distribution has been defined and the density derived. A characterization of the complex multivariate t-distribution is given. A few possible uses of this distribution have been suggested.

  12. Cobalt(III) complex

    Indian Academy of Sciences (India)

    Administrator

    e, 40 µM complex, 10 hrs after dissolution, f, 40 µM complex, after irradiation dose 15 Gy. and H-atoms result in reduction of Co(III) to Co. (II). 6. It is interesting to see in complex containing multiple ligands what is the fate of electron adduct species formed by electron addition. Reduction to. Co(II) and intramolecular transfer ...

  13. Complex Systems and Dependability

    CERN Document Server

    Zamojski, Wojciech; Sugier, Jaroslaw

    2012-01-01

    Typical contemporary complex system is a multifaceted amalgamation of technical, information, organization, software and human (users, administrators and management) resources. Complexity of such a system comes not only from its involved technical and organizational structure but mainly from complexity of information processes that must be implemented in the operational environment (data processing, monitoring, management, etc.). In such case traditional methods of reliability analysis focused mainly on technical level are usually insufficient in performance evaluation and more innovative meth

  14. Lanthanide complexes with pivaloylacetone

    International Nuclear Information System (INIS)

    Eliseeva, S.V.; Chugarov, N.V.; Kuz'mina, N.P.; Martynenko, L.I.; Nichiporuk, R.V.; Ivanov, S.A.

    2003-01-01

    Complexes Ln(pa) 3 ·2H 2 O (Ln=La, Gd, Lu, Hpa - pivaloylacetone) are synthesized and investigated by the methods of element, IR spectroscopic and thermal analyses. Behaviour of the complexes during heating in vacuum is compared with such one for acetylacetonates and dipivaloylmethanates. Structure of the complexes in solution is studied by 1 H NMR and MALDI-MS [ru

  15. Phospholyl-uranium complexes

    International Nuclear Information System (INIS)

    Gradoz, Philippe

    1993-01-01

    After having reported a bibliographical study on penta-methylcyclopentadienyl uranium complexes, and a description of the synthesis and radioactivity of uranium (III) and (IV) boron hydrides compounds, this research thesis reports the study of mono and bis-tetramethyl-phospholyl uranium complexes comprising chloride, boron hydride, alkyl and alkoxide ligands. The third part reports the comparison of structures, stabilities and reactions of homologue complexes in penta-methylcyclopentadienyl and tetramethyl-phospholyl series. The last part addresses the synthesis of tris-phospholyl uranium (III) and (IV) complexes. [fr

  16. Nuclear weapons complex

    International Nuclear Information System (INIS)

    Rezendes, V.S.

    1991-03-01

    In this book, GAO characterizes DOE's January 1991 Nuclear Weapons Complex Reconfiguration Study as a starting point for reaching agreement on solutions to many of the complex's safety and environmental problems. Key decisions still need to be made about the size of the complex, where to relocate plutonium operations, what technologies to use for new tritium production, and what to do with excess plutonium. The total cost for reconfiguring and modernizing the complex is still uncertain, and some management issues remain unresolved. Congress faces a difficult task in making test decisions given the conflicting demands for scarce resources in a time of growing budget deficits and war in the Persian Gulf

  17. Conducting metal dithiolate complexes

    DEFF Research Database (Denmark)

    Underhill, A. E.; Ahmad, M. M.; Turner, D. J.

    1985-01-01

    Further work on the chemical composition of the one-dimensional metallic metal dithiolene complex Li-Pt(mnt) is reported. The electrical conduction and thermopower properties of the nickel and palladium complexes are reported and compared with those of the platinum compound......Further work on the chemical composition of the one-dimensional metallic metal dithiolene complex Li-Pt(mnt) is reported. The electrical conduction and thermopower properties of the nickel and palladium complexes are reported and compared with those of the platinum compound...

  18. Collision-Induced Dissociation of Electrosprayed Protein Complexes: An All-Atom Molecular Dynamics Model with Mobile Protons.

    Science.gov (United States)

    Popa, Vlad; Trecroce, Danielle A; McAllister, Robert G; Konermann, Lars

    2016-06-16

    , and proton affinity causes surprising compensation effects among the various energy terms. It appears that this work provides the most detailed account to date of the mechanism whereby noncovalent protein complexes disassemble during CID.

  19. Visual Complexity: A Review

    Science.gov (United States)

    Donderi, Don C.

    2006-01-01

    The idea of visual complexity, the history of its measurement, and its implications for behavior are reviewed, starting with structuralism and Gestalt psychology at the beginning of the 20th century and ending with visual complexity theory, perceptual learning theory, and neural circuit theory at the beginning of the 21st. Evidence is drawn from…

  20. Complexity in Picture Books

    Science.gov (United States)

    Sierschynski, Jarek; Louie, Belinda; Pughe, Bronwyn

    2015-01-01

    One of the key requirements of Common Core State Standards (CCSS) in English Language Arts is that students are able to read and access complex texts across all grade levels. The CCSS authors emphasize both the limitations and lack of accuracy in the current CCSS model of text complexity, calling for the development of new frameworks. In response…

  1. Method of complex scaling

    International Nuclear Information System (INIS)

    Braendas, E.

    1986-01-01

    The method of complex scaling is taken to include bound states, resonances, remaining scattering background and interference. Particular points of the general complex coordinate formulation are presented. It is shown that care must be exercised to avoid paradoxical situations resulting from inadequate definitions of operator domains. A new resonance localization theorem is presented

  2. Is dense codeswitching complex?

    NARCIS (Netherlands)

    Dorleijn, M.

    In this paper the question is raised to what extent dense code switching can be considered complex. Psycholinguistic experiments indicate that code switching involves cognitive costs, both in production and comprehension, a conclusion that could indicate that code switching is indeed complex. In

  3. Complex conductivity of soils

    NARCIS (Netherlands)

    Revil, A.; Coperey, A.; Shao, Z.; Florsch, N.; Fabricus, I.L.; Deng, Y.; Delsman, J.R.; Pauw, P.S.; Karaoulis, M.; Louw, P.G.B. de; Baaren, E.S. van; Dabekaussen, W.; Menkovic, A.; Gunnink, J.L.

    2017-01-01

    The complex conductivity of soils remains poorly known despite the growing importance of this method in hydrogeophysics. In order to fill this gap of knowledge, we investigate the complex conductivity of 71 soils samples (including four peat samples) and one clean sand in the frequency range 0.1 Hz

  4. Leading healthcare in complexity.

    Science.gov (United States)

    Cohn, Jeffrey

    2014-12-01

    Healthcare institutions and providers are in complexity. Networks of interconnections from relationships and technology create conditions in which interdependencies and non-linear dynamics lead to surprising, unpredictable outcomes. Previous effective approaches to leadership, focusing on top-down bureaucratic methods, are no longer effective. Leading in complexity requires leaders to accept the complexity, create an adaptive space in which innovation and creativity can flourish and then integrate the successful practices that emerge into the formal organizational structure. Several methods for doing adaptive space work will be discussed. Readers will be able to contrast traditional leadership approaches with leading in complexity. They will learn new behaviours that are required of complexity leaders, along with challenges they will face, often from other leaders within the organization.

  5. Integrating complex functions: coordination of nuclear pore complex assembly and membrane expansion of the nuclear envelope requires a family of integral membrane proteins.

    Science.gov (United States)

    Schneiter, Roger; Cole, Charles N

    2010-01-01

    The nuclear envelope harbors numerous large proteinaceous channels, the nuclear pore complexes (NPCs), through which macromolecular exchange between the cytosol and the nucleoplasm occurs. This double-membrane nuclear envelope is continuous with the endoplasmic reticulum and thus functionally connected to such diverse processes as vesicular transport, protein maturation and lipid synthesis. Recent results obtained from studies in Saccharomyces cerevisiae indicate that assembly of the nuclear pore complex is functionally dependent upon maintenance of lipid homeostasis of the ER membrane. Previous work from one of our laboratories has revealed that an integral membrane protein Apq12 is important for the assembly of functional nuclear pores. Cells lacking APQ12 are viable but cannot grow at low temperatures, have aberrant NPCs and a defect in mRNA export. Remarkably, these defects in NPC assembly can be overcome by supplementing cells with a membrane fluidizing agent, benzyl alcohol, suggesting that Apq12 impacts the flexibility of the nuclear membrane, possibly by adjusting its lipid composition when cells are shifted to a reduced temperature. Our new study now expands these findings and reveals that an essential membrane protein, Brr6, shares at least partially overlapping functions with Apq12 and is also required for assembly of functional NPCs. A third nuclear envelope membrane protein, Brl1, is related to Brr6, and is also required for NPC assembly. Because maintenance of membrane homeostasis is essential for cellular survival, the fact that these three proteins are conserved in fungi that undergo closed mitoses, but are not found in metazoans or plants, may indicate that their functions are performed by proteins unrelated at the primary sequence level to Brr6, Brl1 and Apq12 in cells that disassemble their nuclear envelopes during mitosis.

  6. Systemic delivery of siRNA in pumpkin by a plant PHLOEM SMALL RNA-BINDING PROTEIN 1-ribonucleoprotein complex.

    Science.gov (United States)

    Ham, Byung-Kook; Li, Gang; Jia, Weitao; Leary, Julie A; Lucas, William J

    2014-11-01

    In plants, the vascular system, specifically the phloem, functions in delivery of small RNA (sRNA) to exert epigenetic control over developmental and defense-related processes. Although the importance of systemic sRNA delivery has been established, information is currently lacking concerning the nature of the protein machinery involved in this process. Here, we show that a PHLOEM SMALL-RNA BINDING PROTEIN 1 (PSRP1) serves as the basis for formation of an sRNA ribonucleoprotein complex (sRNPC) that delivers sRNA (primarily 24 nt) to sink organs. Assembly of this complex is facilitated through PSRP1 phosphorylation by a phloem-localized protein kinase, PSRPK1. During long-distance transport, PSRP1-sRNPC is stable against phloem phosphatase activity. Within target tissues, phosphatase activity results in disassembly of PSRP1-sRNPC, a process that is probably required for unloading cargo sRNA into surrounding cells. These findings provide an insight into the mechanism involved in delivery of sRNA associated with systemic gene silencing in plants. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  7. Selenophene transition metal complexes

    Energy Technology Data Exchange (ETDEWEB)

    White, Carter James [Iowa State Univ., Ames, IA (United States)

    1994-07-27

    This research shows that selenophene transition metal complexes have a chemistry that is similar to their thiophene analogs. Selenophene coordination has been demonstrated and confirmed by molecular structure in both the η5- and the η1(Se)-coordination modes. The reaction chemistry of selenophene complexes closely resembles that of the analogous thiophene complexes. One major difference, however, is that selenophene is a better donor ligand than thiophene making the selenophene complexes more stable than the corresponding thiophene complexes. The 77Se NMR chemical shift values for selenophene complexes fall within distinct regions primarily depending on the coordination mode of the selenophene ligand. In the final paper, the C-H bond activation of η1(S)-bound thiophenes, η1(S)-benzothiophene and η1(Se)-bound selenophenes has been demonstrated. The deprotonation and rearrangement of the η1(E)-bound ligand to the carbon bound L-yl complex readily occurs in the presence of base. Reprotonation with a strong acid gives a carbene complex that is unreactive towards nucleophilic attack at the carbene carbon and is stable towards exposure to air. The molecular structure of [Cp(NO)(PPh3)Re(2-benzothioenylcarbene)]O3SCF3 was determined and contains a Re-C bond with substantial double bond character. Methyl substitution for the thienylcarbene or selenylcarbene gives a carbene that rearranges thermally to give back the η1(E)-bound complex. Based on these model reactions, a new mechanism for the H/D exchange of thiophene over the hydrodesulfurization catalyst has been proposed.

  8. Study of complex modes

    International Nuclear Information System (INIS)

    Pastrnak, J.W.

    1986-01-01

    This eighteen-month study has been successful in providing the designer and analyst with qualitative guidelines on the occurrence of complex modes in the dynamics of linear structures, and also in developing computer codes for determining quantitatively which vibration modes are complex and to what degree. The presence of complex modes in a test structure has been verified. Finite element analysis of a structure with non-proportional dumping has been performed. A partial differential equation has been formed to eliminate possible modeling errors

  9. Nuclear weapons complex

    International Nuclear Information System (INIS)

    Rezendes, V.S.

    1992-04-01

    In addition to long-standing safety and environmental problems plaguing the nuclear weapons complex, this paper reports that the Department of Energy (DOE) faces a major new challenge-how to reconfigure the weapons complex to meet the nation's defense needs in the 21st century. Key decisions still need to be made about the size of the complex; where, if necessary, to relocate various operations; what technologies to use for new tritium production; and what to do with excess weapons-grade material. The choices confronting DOE and Congress are difficult given the conflicting demands for limited resources

  10. Managing complex child law

    DEFF Research Database (Denmark)

    Svendsen, Idamarie Leth

    2017-01-01

    The article reports the findings of a qualitative study of Danish legal regulation of the public initial assessment of children and young persons and municipal practitioners’ decision-making under this regulation. The regulation mirrors new and complex relations between families and society...... in the form of 7 individual vignette interviews with municipal mid-level managers and professional consultants in five Danish municipalities. The study finds that the regulation is more complex than it looks, and that the complexity is handled through simplifying decision-making patterns that can be seen...

  11. Indicators: Physical Habitat Complexity

    Science.gov (United States)

    Physical habitat complexity measures the amount and variety of all types of cove at the water’s edge in lakes. In general, dense and varied shoreline habitat is able to support more diverse communities of aquatic life.

  12. Several complex variables

    International Nuclear Information System (INIS)

    Field, M.J.

    1976-01-01

    Topics discussed include the elementary of holomorphic functions of several complex variables; the Weierstrass preparation theorem; meromorphic functions, holomorphic line bundles and divisors; elliptic operators on compact manifolds; hermitian connections; the Hodge decomposition theorem. ( author)

  13. Power grid complexity

    Energy Technology Data Exchange (ETDEWEB)

    Mei, Shengwei; Zhang, Xuemin [Tsinghua Univ., Beijing, BJ (China). Dept. of Electrical Engineering; Cao, Ming [Groningen Univ. (Netherlands). Faculty of Mathematics and Natural Sciences

    2011-07-01

    ''Power Grid Complexity'' introduces the complex system theory known as self-organized criticality (SOC) theory and complex network theory, and their applications to power systems. It studies the network characteristics of power systems, such as their small-world properties, structural vulnerability, decomposition and coordination strategies, and simplification and equivalence methods. The book also establishes four blackout models based on SOC theory through which the SOC of power systems is studied at both the macroscopic and microscopic levels. Additionally, applications of complex system theory in power system planning and emergency management platforms are also discussed in depth. This book can serve as a useful reference for engineers and researchers working with power systems. (orig.)

  14. Statistical electromagnetics: Complex cavities

    NARCIS (Netherlands)

    Naus, H.W.L.

    2008-01-01

    A selection of the literature on the statistical description of electromagnetic fields and complex cavities is concisely reviewed. Some essential concepts, for example, the application of the central limit theorem and the maximum entropy principle, are scrutinized. Implicit assumptions, biased

  15. Complex and unpredictable Cardano

    Science.gov (United States)

    Ekert, Artur

    2008-08-01

    This purely recreational paper is about one of the most colorful characters of the Italian Renaissance, Girolamo Cardano, and the discovery of two basic ingredients of quantum theory, probability and complex numbers.

  16. Coxeter-like complexes

    Directory of Open Access Journals (Sweden)

    Eric Babson

    2004-12-01

    Full Text Available Motivated by the Coxeter complex associated to a Coxeter system (W,S, we introduce a simplicial regular cell complex Δ(G,S with a G-action associated to any pair (G,S where G is a group and S is a finite set of generators for G which is minimal with respect to inclusion. We examine the topology of Δ(G,S, and in particular the representations of G on its homology groups. We look closely at the case of the symmetric group S n minimally generated by (not necessarily adjacent transpositions, and their type-selected subcomplexes. These include not only the Coxeter complexes of type A, but also the well-studied chessboard complexes.

  17. Physical Sciences Complex

    Data.gov (United States)

    Federal Laboratory Consortium — This 88,000 square foot complex is used to investigate basic physical science in support of missile technology development. It incorporates office space, dedicated...

  18. Life: Complexity and Diversity

    Indian Academy of Sciences (India)

    tinual increase in the diversity of life over evolutionary time. Ways of ... Centre for Ecological. Scienc'es .... plants evolved flowers to attract pollinators and reward them with .... with the evolving complexity of their interactions in communi- ties.

  19. Complex Flow Workshop Report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2012-05-01

    This report documents findings from a workshop on the impacts of complex wind flows in and out of wind turbine environments, the research needs, and the challenges of meteorological and engineering modeling at regional, wind plant, and wind turbine scales.

  20. Complexity for Artificial Substrates (

    NARCIS (Netherlands)

    Loke, L.H.L.; Jachowski, N.R.; Bouma, T.J.; Ladle, R.J.; Todd, P.A.

    2014-01-01

    Physical habitat complexity regulates the structure and function of biological communities, although the mechanisms underlying this relationship remain unclear. Urbanisation, pollution, unsustainable resource exploitation and climate change have resulted in the widespread simplification (and loss)

  1. Photocytotoxic lanthanide complexes

    Indian Academy of Sciences (India)

    Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 ... complexes showing photoactivated DNA cleavage activity and cytotoxicity in cancer cells. .... considerable importance for their selectivity in killing.

  2. Complex Networks IX

    CERN Document Server

    Coronges, Kate; Gonçalves, Bruno; Sinatra, Roberta; Vespignani, Alessandro; Proceedings of the 9th Conference on Complex Networks; CompleNet 2018

    2018-01-01

    This book aims to bring together researchers and practitioners working across domains and research disciplines to measure, model, and visualize complex networks. It collects the works presented at the 9th International Conference on Complex Networks (CompleNet) 2018 in Boston, MA in March, 2018. With roots in physical, information and social science, the study of complex networks provides a formal set of mathematical methods, computational tools and theories to describe prescribe and predict dynamics and behaviors of complex systems. Despite their diversity, whether the systems are made up of physical, technological, informational, or social networks, they share many common organizing principles and thus can be studied with similar approaches. This book provides a view of the state-of-the-art in this dynamic field and covers topics such as group decision-making, brain and cellular connectivity, network controllability and resiliency, online activism, recommendation systems, and cyber security.

  3. Involvement of complexin 2 in docking, locking and unlocking of different SNARE complexes during sperm capacitation and induced acrosomal exocytosis.

    Directory of Open Access Journals (Sweden)

    Pei-Shiue J Tsai

    Full Text Available Acrosomal exocytosis (AE is an intracellular multipoint fusion reaction of the sperm plasma membrane (PM with the outer acrosomal membrane (OAM. This unique exocytotic event enables the penetration of the sperm through the zona pellucida of the oocyte. We previously observed a stable docking of OAM to the PM brought about by the formation of the trans-SNARE complex (syntaxin 1B, SNAP 23 and VAMP 3. By using electron microscopy, immunochemistry and immunofluorescence techniques in combination with functional studies and proteomic approaches, we here demonstrate that calcium ionophore-induced AE results in the formation of unilamellar hybrid membrane vesicles containing a mixture of components originating from the two fused membranes. These mixed vesicles (MV do not contain the earlier reported trimeric SNARE complex but instead possess a novel trimeric SNARE complex that contained syntaxin 3, SNAP 23 and VAMP 2, with an additional SNARE interacting protein, complexin 2. Our data indicate that the earlier reported raft and capacitation-dependent docking phenomenon between the PM and OAM allows a specific rearrangement of molecules between the two docked membranes and is involved in (1 recruiting SNAREs and complexin 2 in the newly formed lipid-ordered microdomains, (2 the assembly of a fusion-driving SNARE complex which executes Ca(2+-dependent AE, (3 the disassembly of the earlier reported docking SNARE complex, (4 the recruitment of secondary zona binding proteins at the zona interacting sperm surface. The possibility to study separate and dynamic interactions between SNARE proteins, complexin and Ca(2+ which are all involved in AE make sperm an ideal model for studying exocytosis.

  4. Provability, complexity, grammars

    CERN Document Server

    Beklemishev, Lev; Vereshchagin, Nikolai

    1999-01-01

    The book contains English translations of three outstanding dissertations in mathematical logic and complexity theory. L. Beklemishev proves that all provability logics must belong to one of the four previously known classes. The dissertation of M. Pentus proves the Chomsky conjecture about the equivalence of two approaches to formal languages: the Chomsky hierarchy and the Lambek calculus. The dissertation of N. Vereshchagin describes a general framework for criteria of reversability in complexity theory.

  5. Conversation, coupling and complexity

    DEFF Research Database (Denmark)

    Fusaroli, Riccardo; Abney, Drew; Bahrami, Bahador

    We investigate the linguistic co-construction of interpersonal synergies. By applying a measure of coupling between complex systems to an experimentally elicited corpus of joint decision dialogues, we show that interlocutors’ linguistic behavior displays increasing signature of multi-scale coupling......, known as complexity matching, over the course of interaction. Furthermore, we show that stronger coupling corresponds with more effective interaction, as measured by collective task performance....

  6. Advances in network complexity

    CERN Document Server

    Dehmer, Matthias; Emmert-Streib, Frank

    2013-01-01

    A well-balanced overview of mathematical approaches to describe complex systems, ranging from chemical reactions to gene regulation networks, from ecological systems to examples from social sciences. Matthias Dehmer and Abbe Mowshowitz, a well-known pioneer in the field, co-edit this volume and are careful to include not only classical but also non-classical approaches so as to ensure topicality. Overall, a valuable addition to the literature and a must-have for anyone dealing with complex systems.

  7. Electrospun complexes - functionalised nanofibres

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, T.; Wolf, M.; Dreyer, B.; Unruh, D.; Krüger, C.; Menze, M. [Leibniz University Hannover, Institute of Inorganic Chemistry (Germany); Sindelar, R. [University of Applied Science Hannover, Faculty II (Germany); Klingelhöfer, G. [Gutenberg-University, Institute of Inorganic and Analytic Chemistry (Germany); Renz, F., E-mail: renz@acd.uni-hannover.de [Leibniz University Hannover, Institute of Inorganic Chemistry (Germany)

    2016-12-15

    Here we present a new approach of using iron-complexes in electro-spun fibres. We modify poly(methyl methacrylate) (PMMA) by replacing the methoxy group with Diaminopropane or Ethylenediamine. The complex is bound covalently via an imine-bridge or an amide. The resulting polymer can be used in the electrospinning process without any further modifications in method either as pure reagent or mixed with small amounts of not functionalised polymer resulting in fibres of different qualities (Fig. 1).

  8. MANAGEMENT OF SPORT COMPLEXES

    Directory of Open Access Journals (Sweden)

    Marian STAN

    2015-07-01

    Full Text Available The actuality of the investigated theme. Nowadays, human evolution, including his intellectual development, proves the fact that especially the creation manpower and the employment was the solution of all life’s ambitions in society. So, the fact is that in reality, man is the most important capital of the society. Also, in an individual’s life, the practice of sport plays a significant role and that’s why the initiation, the launch and the management of sports complexes activity reveal the existence of specific management features that we will identify and explain in the current study. The aim of the research refers to the elaboration of a theoretical base of the management of the sport complexes, to the pointing of the factors that influence the efficient existence and function of a sport complex in our country and to the determination of the responsibilities that have a manager who directs successfully the activity of the sport complexes. The investigation is based on theoretical methods, such as: scientific documentation, analysis, synthesis, comparison and on empirical research methods, like: study of researched literature and observation. The results of the research indicate the fact that the profitability of a sport complex must assure a particular structure to avoid the bankruptcy risk and also, that the administration of the sport complexes activity must keep in view the reliable functions of the contemporaneous management.

  9. Organotin complexes with phosphines

    International Nuclear Information System (INIS)

    Passos, B. de F.T.; Jesus Filho, M.F. de; Filgueiras, C.A.L.; Abras, A.

    1988-01-01

    A series of organotin complexes was prepared involving phosphines bonded to the organotin moiety. The series include derivatives of SnCl x Ph 4-x (where x varied from zero to four with the phosphines Ph 3 P, (Ph 2 P)CH 2 , (Ph 2 P) 2 (CH 2 ) 2 , cis-(Ph 2 P)CH 2 , and CH 3 C(CH 2 PPh 2 ) 3 . A host of new complexes was obtained, showing different stoichiometries, bonding modes, and coordination numbers around the tin atom. These complexes were characterized by several different chemical and physical methods. The 119 Sn Moessbauer parameters varied differently. Whereas isomer shift values did not great variation for each group of complexs with the same organotin parent (SnCl x Ph 4-x ), reflecting a small change in s charge distribution on the Sn atom upon complexation, quadrupole splitting results varied widely, however, when the parent organotin compound was wholly symmetric (SnCl 4 and SnPPh 4 ), the complexes also tended to show quadrupole splitting values approaching zero. (author)

  10. Hypoxia targeting copper complexes

    International Nuclear Information System (INIS)

    Dearling, J.L.

    1998-11-01

    The importance and incidence of tumour hypoxia, its measurement and current treatments available, including pharmacological and radiopharmacological methods of targeting hypoxia, are discussed. A variety of in vitro and in vivo methods for imposing hypoxia have been developed and are reviewed. Copper, its chemistry, biochemistry and radiochemistry, the potential for use of copper radionuclides and its use to date in this field is considered with particular reference to the thiosemicarbazones. Their biological activity, metal chelation, in vitro and in vivo studies of their radiocopper complexes and the potential for their use as hypoxia targeting radiopharmaceuticals is described. The reduction of the copper(II) complex to copper(l), its pivotal importance in their biological behaviour, and the potential for manipulation of this to effect hypoxia selectivity are described. An in vitro method for assessing the hypoxia selectivity of radiopharmaceuticals is reported. The rapid deoxygenation and high viability of a mammalian cell culture in this system is discussed and factors which may affect the cellular uptake of a radiopharmaceutical are described. The design, synthesis and complexation with copper and radiocopper of a range of bis(thiosemicarbazones) is reported. Synthesis of these compounds is simple giving high yields of pure products. The characteristics of the radiocopper complexes ( 64 Cu) including lipophilicity and redox activity are reported (reduction potentials in the range -0.314 - -0.590 V). High cellular uptakes of the radiocopper complexes of the ligands, in hypoxic and normoxic EMT6 and CHO320 cells, were observed. Extremes of selectivity are shown ranging from the hypoxia selective 64 Cu(II)ATSM to normoxic cell selective 64 Cu(II)GTS. The selectivities observed are compared with the physico chemical characteristics of the complexes. A good correlation exists between selectivity of the complex and its Cu(II)/Cu(I) reduction potential, with hypoxia

  11. Complexity and Dynamical Depth

    Directory of Open Access Journals (Sweden)

    Terrence Deacon

    2014-07-01

    Full Text Available We argue that a critical difference distinguishing machines from organisms and computers from brains is not complexity in a structural sense, but a difference in dynamical organization that is not well accounted for by current complexity measures. We propose a measure of the complexity of a system that is largely orthogonal to computational, information theoretic, or thermodynamic conceptions of structural complexity. What we call a system’s dynamical depth is a separate dimension of system complexity that measures the degree to which it exhibits discrete levels of nonlinear dynamical organization in which successive levels are distinguished by local entropy reduction and constraint generation. A system with greater dynamical depth than another consists of a greater number of such nested dynamical levels. Thus, a mechanical or linear thermodynamic system has less dynamical depth than an inorganic self-organized system, which has less dynamical depth than a living system. Including an assessment of dynamical depth can provide a more precise and systematic account of the fundamental difference between inorganic systems (low dynamical depth and living systems (high dynamical depth, irrespective of the number of their parts and the causal relations between them.

  12. The Orion complex

    International Nuclear Information System (INIS)

    Goudis, C.

    1982-01-01

    This work deals with some of the most typical complexes of interstellar matter and presents a holistic view of the well studied complexes in Orion, built on information derived from various branches of modern astrophysics. A wealth of published data is presented in the form of photographs, contour maps, diagrams and numerous heavily annotated tables. Chapter 1, which is concerned with the large scale view of the Orion region, outlines the morphology of the area and examines in particular the nature of Barnard's Loop and the associated filamentary structure in addition to the origin of the I Orion OB association. Chapter 2 focuses on the Great Orion Nebula (M42 or NGC 1976) and the small H II region to the north (M43 or NGC 1982). Chapter 3 examines the Orion Complex as a whole, i.e. the H II regions M42 and M43, the associated molecular clouds OMC 1 and OMC 2 and their interrelations. Chapter 4 contains a discussion of the empirical models introduced to attempt to explain certain aspects of this very complex region, and chapter 5 investigates the second prominent H II region and molecular cloud complex, NGC 2024 (Orion B, W12). (Auth.)

  13. Complexity of Economical Systems

    Directory of Open Access Journals (Sweden)

    G. P. Pavlos

    2015-01-01

    Full Text Available In this study new theoretical concepts are described concerning the interpretation of economical complex dynamics. In addition a summary of an extended algorithm of nonlinear time series analysis is provided which is applied not only in economical time series but also in other physical complex systems (e.g. [22, 24]. In general, Economy is a vast and complicated set of arrangements and actions wherein agents—consumers, firms, banks, investors, government agencies—buy and sell, speculate, trade, oversee, bring products into being, offer services, invest in companies, strategize, explore, forecast, compete, learn, innovate, and adapt. As a result the economic and financial variables such as foreign exchange rates, gross domestic product, interest rates, production, stock market prices and unemployment exhibit large-amplitude and aperiodic fluctuations evident in complex systems. Thus, the Economics can be considered as spatially distributed non-equilibrium complex system, for which new theoretical concepts, such as Tsallis non extensive statistical mechanics and strange dynamics, percolation, nonGaussian, multifractal and multiscale dynamics related to fractional Langevin equations can be used for modeling and understanding of the economical complexity locally or globally.

  14. Complexes and imagination.

    Science.gov (United States)

    Kast, Verena

    2014-11-01

    Fantasies as imaginative activities are seen by Jung as expressions of psychic energy. In the various descriptions of active imagination the observation of the inner image and the dialogue with inner figures, if possible, are important. The model of symbol formation, as Jung describes it, can be experienced in doing active imagination. There is a correspondence between Jung's understanding of complexes and our imaginations: complexes develop a fantasy life. Complex episodes are narratives of difficult dysfunctional relationship episodes that have occurred repeatedly and are internalized with episodic memory. This means that the whole complex episode (the image for the child and the image for the aggressor, connected with emotions) is internalized and can get constellated in everyday relationship. Therefore inner dialogues do not necessarily qualify as active imaginations, often they are the expression of complex-episodes, very similar to fruitless soliloquies. If imaginations of this kind are repeated, new symbols and new possibilities of behaviour are not found. On the contrary, old patterns of behaviour and fantasies are perpetuated and become cemented. Imaginations of this kind need an intervention by the analyst. In clinical examples different kinds of imaginations are discussed. © 2014, The Society of Analytical Psychology.

  15. Algorithmic Relative Complexity

    Directory of Open Access Journals (Sweden)

    Daniele Cerra

    2011-04-01

    Full Text Available Information content and compression are tightly related concepts that can be addressed through both classical and algorithmic information theories, on the basis of Shannon entropy and Kolmogorov complexity, respectively. The definition of several entities in Kolmogorov’s framework relies upon ideas from classical information theory, and these two approaches share many common traits. In this work, we expand the relations between these two frameworks by introducing algorithmic cross-complexity and relative complexity, counterparts of the cross-entropy and relative entropy (or Kullback-Leibler divergence found in Shannon’s framework. We define the cross-complexity of an object x with respect to another object y as the amount of computational resources needed to specify x in terms of y, and the complexity of x related to y as the compression power which is lost when adopting such a description for x, compared to the shortest representation of x. Properties of analogous quantities in classical information theory hold for these new concepts. As these notions are incomputable, a suitable approximation based upon data compression is derived to enable the application to real data, yielding a divergence measure applicable to any pair of strings. Example applications are outlined, involving authorship attribution and satellite image classification, as well as a comparison to similar established techniques.

  16. Nuclear weapons complex

    International Nuclear Information System (INIS)

    Peach, J.D.

    1991-02-01

    In this paper, GAO provides its views on DOE's January 1991 Nuclear Weapons Complex Reconfiguration Study. GAO believes that DOE's new reconfiguration study provides a starting point for reaching agreement on solutions to many of the complex's problems. Key decisions still need to be made about the size of the complex, where to relocate plutonium operations, what technologies should be used for new tritium production, and what to do with excess plutonium. The total cost for reconfiguring and modernizing is still uncertain and some management issues remain unresolved. Congress faces a difficult task in making these decisions given the conflicting demands for scare resources in a time of growing budget deficits and war in the Persian Gulf

  17. Can Complexity be Planned?

    Directory of Open Access Journals (Sweden)

    Ilona Koutny

    2015-04-01

    Full Text Available The long accepted complexity invariance of human languages has become controversial within the last decade. In investigations of the problem, both creole and planned languages have often been neglected. After a presentation of the scope of the invariance problem and the proposition of the natural to planned language continuum, this article will discuss the contribution of planned languages. It will analyze the complexity of Esperanto at the phonological, morphological, syntactic and semantic levels, using linguistic data bases. The role of the L2 speech community and development of the language will also be taken into account when discussing the endurance of the same level of simplicity of this planned international language. The author argues that complexity can be variable and to some extent planned and maintained.

  18. Introduction to complex plasmas

    International Nuclear Information System (INIS)

    Bonitz, Michael; Ludwig, Patrick; Horing, Norman

    2010-01-01

    Complex plasmas differ from traditional plasmas in many ways: these are low-temperature high pressure systems containing nanometer to micrometer size particles which may be highly charged and strongly interacting. The particles may be chemically reacting or be in contact with solid surfaces, and the electrons may show quantum behaviour. These interesting properties have led to many applications of complex plasmas in technology, medicine and science. Yet complex plasmas are extremely complicated, both experimentally and theoretically, and require a variety of new approaches which go beyond standard plasma physics courses. This book fills this gap presenting an introduction to theory, experiment and computer simulation in this field. Based on tutorial lectures at a very successful recent Summer Institute, the presentation is ideally suited for graduate students, plasma physicists and experienced undergraduates. (orig.)

  19. Introduction to Complex Plasmas

    CERN Document Server

    Bonitz, Michael; Ludwig, Patrick

    2010-01-01

    Complex plasmas differ from traditional plasmas in many ways: these are low-temperature high pressure systems containing nanometer to micrometer size particles which may be highly charged and strongly interacting. The particles may be chemically reacting or be in contact with solid surfaces, and the electrons may show quantum behaviour. These interesting properties have led to many applications of complex plasmas in technology, medicine and science. Yet complex plasmas are extremely complicated, both experimentally and theoretically, and require a variety of new approaches which go beyond standard plasma physics courses. This book fills this gap presenting an introduction to theory, experiment and computer simulation in this field. Based on tutorial lectures at a very successful recent Summer Institute, the presentation is ideally suited for graduate students, plasma physicists and experienced undergraduates.

  20. BRAND program complex

    International Nuclear Information System (INIS)

    Androsenko, A.A.; Androsenko, P.A.

    1983-01-01

    A description is given of the structure, input procedure and recording rules of initial data for the BRAND programme complex intended for the Monte Carlo simulation of neutron physics experiments. The BRAND complex ideology is based on non-analogous simulation of the neutron and photon transport process (statistic weights are used, absorption and escape of particles from the considered region is taken into account, shifted readouts from a coordinate part of transition nucleus density are applied, local estimations, etc. are used). The preparation of initial data for three sections is described in detail: general information for Monte Carlo calculation, source definition and data for describing the geometry of the system. The complex is to be processed with the BESM-6 computer, the basic programming lan-- guage is FORTRAN, volume - more than 8000 operators

  1. Synchronization in complex networks

    Energy Technology Data Exchange (ETDEWEB)

    Arenas, A.; Diaz-Guilera, A.; Moreno, Y.; Zhou, C.; Kurths, J.

    2007-12-12

    Synchronization processes in populations of locally interacting elements are in the focus of intense research in physical, biological, chemical, technological and social systems. The many efforts devoted to understand synchronization phenomena in natural systems take now advantage of the recent theory of complex networks. In this review, we report the advances in the comprehension of synchronization phenomena when oscillating elements are constrained to interact in a complex network topology. We also overview the new emergent features coming out from the interplay between the structure and the function of the underlying pattern of connections. Extensive numerical work as well as analytical approaches to the problem are presented. Finally, we review several applications of synchronization in complex networks to different disciplines: biological systems and neuroscience, engineering and computer science, and economy and social sciences.

  2. Simulation in Complex Modelling

    DEFF Research Database (Denmark)

    Nicholas, Paul; Ramsgaard Thomsen, Mette; Tamke, Martin

    2017-01-01

    This paper will discuss the role of simulation in extended architectural design modelling. As a framing paper, the aim is to present and discuss the role of integrated design simulation and feedback between design and simulation in a series of projects under the Complex Modelling framework. Complex...... performance, engage with high degrees of interdependency and allow the emergence of design agency and feedback between the multiple scales of architectural construction. This paper presents examples for integrated design simulation from a series of projects including Lace Wall, A Bridge Too Far and Inflated...... Restraint developed for the research exhibition Complex Modelling, Meldahls Smedie Gallery, Copenhagen in 2016. Where the direct project aims and outcomes have been reported elsewhere, the aim for this paper is to discuss overarching strategies for working with design integrated simulation....

  3. Modeling Complex Systems

    CERN Document Server

    Boccara, Nino

    2010-01-01

    Modeling Complex Systems, 2nd Edition, explores the process of modeling complex systems, providing examples from such diverse fields as ecology, epidemiology, sociology, seismology, and economics. It illustrates how models of complex systems are built and provides indispensable mathematical tools for studying their dynamics. This vital introductory text is useful for advanced undergraduate students in various scientific disciplines, and serves as an important reference book for graduate students and young researchers. This enhanced second edition includes: . -recent research results and bibliographic references -extra footnotes which provide biographical information on cited scientists who have made significant contributions to the field -new and improved worked-out examples to aid a student’s comprehension of the content -exercises to challenge the reader and complement the material Nino Boccara is also the author of Essentials of Mathematica: With Applications to Mathematics and Physics (Springer, 2007).

  4. The multitalented Mediator complex.

    Science.gov (United States)

    Carlsten, Jonas O P; Zhu, Xuefeng; Gustafsson, Claes M

    2013-11-01

    The Mediator complex is needed for regulated transcription of RNA polymerase II (Pol II)-dependent genes. Initially, Mediator was only seen as a protein bridge that conveyed regulatory information from enhancers to the promoter. Later studies have added many other functions to the Mediator repertoire. Indeed, recent findings show that Mediator influences nearly all stages of transcription and coordinates these events with concomitant changes in chromatin organization. We review the multitude of activities associated with Mediator and discuss how this complex coordinates transcription with other cellular events. We also discuss the inherent difficulties associated with in vivo characterization of a coactivator complex that can indirectly affect diverse cellular processes via changes in gene transcription. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Modeling Complex Time Limits

    Directory of Open Access Journals (Sweden)

    Oleg Svatos

    2013-01-01

    Full Text Available In this paper we analyze complexity of time limits we can find especially in regulated processes of public administration. First we review the most popular process modeling languages. There is defined an example scenario based on the current Czech legislature which is then captured in discussed process modeling languages. Analysis shows that the contemporary process modeling languages support capturing of the time limit only partially. This causes troubles to analysts and unnecessary complexity of the models. Upon unsatisfying results of the contemporary process modeling languages we analyze the complexity of the time limits in greater detail and outline lifecycles of a time limit using the multiple dynamic generalizations pattern. As an alternative to the popular process modeling languages there is presented PSD process modeling language, which supports the defined lifecycles of a time limit natively and therefore allows keeping the models simple and easy to understand.

  6. Large erupted complex odontoma

    Directory of Open Access Journals (Sweden)

    Vijeev Vasudevan

    2009-01-01

    Full Text Available Odontomas are a heterogeneous group of jaw bone lesions, classified as odontogenic tumors which usually include well-diversified dental tissues. Odontoma is a term introduced to the literature by Broca in 1867. Trauma, infection and hereditary factors are the possible causes of forming this kind of lesions. Among odontogenic tumors, they constitute about 2/3 of cases. These lesions usually develop slowly and asymptomatically, and in most cases they do not cross the bone borders. Two types of odontoma are recognized: compound and complex. Complex odontomas are less common than the compound variety in the ratio 1:2.3. Eruption of an odontoma in the oral cavity is rare. We present a case of complex odontoma, in which apparent eruption has occurred in the area of the right maxillary second molar region.

  7. Alanine water complexes.

    Science.gov (United States)

    Vaquero, Vanesa; Sanz, M Eugenia; Peña, Isabel; Mata, Santiago; Cabezas, Carlos; López, Juan C; Alonso, José L

    2014-04-10

    Two complexes of alanine with water, alanine-(H2O)n (n = 1,2), have been generated by laser ablation of the amino acid in a supersonic jet containing water vapor and characterized using Fourier transform microwave spectroscopy. In the observed complexes, water molecules bind to the carboxylic group of alanine acting as both proton donors and acceptors. In alanine-H2O, the water molecule establishes two intermolecular hydrogen bonds forming a six-membered cycle, while in alanine-(H2O)2 the two water molecules establish three hydrogen bonds forming an eight-membered ring. In both complexes, the amino acid moiety is in its neutral form and shows the conformation observed to be the most stable for the bare molecule. The microsolvation study of alanine-(H2O)n (n = 1,2) can be taken as a first step toward understanding bulk properties at a microscopic level.

  8. Philosophy of complex systems

    CERN Document Server

    2011-01-01

    The domain of nonlinear dynamical systems and its mathematical underpinnings has been developing exponentially for a century, the last 35 years seeing an outpouring of new ideas and applications and a concomitant confluence with ideas of complex systems and their applications from irreversible thermodynamics. A few examples are in meteorology, ecological dynamics, and social and economic dynamics. These new ideas have profound implications for our understanding and practice in domains involving complexity, predictability and determinism, equilibrium, control, planning, individuality, responsibility and so on. Our intention is to draw together in this volume, we believe for the first time, a comprehensive picture of the manifold philosophically interesting impacts of recent developments in understanding nonlinear systems and the unique aspects of their complexity. The book will focus specifically on the philosophical concepts, principles, judgments and problems distinctly raised by work in the domain of comple...

  9. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...... of parameter spaces into structurally stable domains, and a description of the bifurcations. For this reason, the talk will focus on these questions for complex polynomial vector fields.......The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...

  10. Complex manifolds in relativity

    International Nuclear Information System (INIS)

    Flaherty, E.J. Jr.

    1975-01-01

    Complex manifold theory is applied to the study of certain problems in general relativity. The first half of the work is devoted to the mathematical theory of complex manifold. Then a brief review of general relativity is given. It is shown that any spacetime admits locally an almost Hermitian structure, suitably modified to be compatible with the indefinite metric of spacetime. This structure is integrable if and only if the spacetime admits two geodesic and shearfree null congruences, thus in particular if the spacetime is type D vacuum or electrified. The structure is ''half-integrable'' in a suitable sense if and only if the spacetime admits one geodesic and shearfree null congruence, thus in particular for all algebraically special vacuum spacetimes. Conditions for the modified Hermitian spacetime to be Kahlerian are presented. The most general metric for such a modified Kahlerian spacetime is found. It is shown that the type D vacuum and electrified spacetimes are conformally related to modified Kahlerian spacetimes by a generally complex conformal factor. These latter are shown to possess a very rich structure, including the existence of Killing tensors and Killing vectors. A new ''explanation'' of Newman's complex coordinate transformations is given. It is felt to be superior to previous ''explanations'' on several counts. For example, a physical interpretation in terms of a symmetry group is given. The existence of new complex coordinate transformations is established: Nt is shown that any type D vacuum spacetime is obtainable from either Schwarzschild spacetime or ''C'' spacetime by a complex coordinate transformation. Finally, some related topics are discussed and areas for future work are outlined. (Diss. Abstr. Int., B)

  11. Complex quantum groups

    International Nuclear Information System (INIS)

    Drabant, B.; Schlieker, M.

    1993-01-01

    The complex quantum groups are constructed. They are q-deformations of the real Lie groups which are obtained as the complex groups corresponding to the Lie algebras of type A n-1 , B n , C n . Following the ideas of Faddeev, Reshetikhin and Takhtajan Hopf algebras of regular functionals U R for these complexified quantum groups are constructed. One has thus in particular found a construction scheme for the q-Lorentz algebra to be identified as U(sl q (2,C). (orig.)

  12. Complex function theory

    CERN Document Server

    Sarason, Donald

    2007-01-01

    Complex Function Theory is a concise and rigorous introduction to the theory of functions of a complex variable. Written in a classical style, it is in the spirit of the books by Ahlfors and by Saks and Zygmund. Being designed for a one-semester course, it is much shorter than many of the standard texts. Sarason covers the basic material through Cauchy's theorem and applications, plus the Riemann mapping theorem. It is suitable for either an introductory graduate course or an undergraduate course for students with adequate preparation. The first edition was published with the title Notes on Co

  13. Complex matrix model duality

    International Nuclear Information System (INIS)

    Brown, T.W.

    2010-11-01

    The same complex matrix model calculates both tachyon scattering for the c=1 non-critical string at the self-dual radius and certain correlation functions of half-BPS operators in N=4 super- Yang-Mills. It is dual to another complex matrix model where the couplings of the first model are encoded in the Kontsevich-like variables of the second. The duality between the theories is mirrored by the duality of their Feynman diagrams. Analogously to the Hermitian Kontsevich- Penner model, the correlation functions of the second model can be written as sums over discrete points in subspaces of the moduli space of punctured Riemann surfaces. (orig.)

  14. Resilience and Complexity

    DEFF Research Database (Denmark)

    Dahlberg, Rasmus

    2015-01-01

    This paper explores two key concepts: resilience and complexity. The first is understood as an emergent property of the latter, and their inter-relatedness is discussed using a three tier approach. First, by exploring the discourse of each concept, next, by analyzing underlying relationships and...... robust. Robustness is a property of simple or complicated systems characterized by predictable behavior, enabling the system to bounce back to its normal state following a perturbation. Resilience, however, is an emergent property of complex adaptive systems. It is suggested that this distinction...

  15. Theories of computational complexity

    CERN Document Server

    Calude, C

    1988-01-01

    This volume presents four machine-independent theories of computational complexity, which have been chosen for their intrinsic importance and practical relevance. The book includes a wealth of results - classical, recent, and others which have not been published before.In developing the mathematics underlying the size, dynamic and structural complexity measures, various connections with mathematical logic, constructive topology, probability and programming theories are established. The facts are presented in detail. Extensive examples are provided, to help clarify notions and constructions. The lists of exercises and problems include routine exercises, interesting results, as well as some open problems.

  16. Planning Complex Projects Automatically

    Science.gov (United States)

    Henke, Andrea L.; Stottler, Richard H.; Maher, Timothy P.

    1995-01-01

    Automated Manifest Planner (AMP) computer program applies combination of artificial-intelligence techniques to assist both expert and novice planners, reducing planning time by orders of magnitude. Gives planners flexibility to modify plans and constraints easily, without need for programming expertise. Developed specifically for planning space shuttle missions 5 to 10 years ahead, with modifications, applicable in general to planning other complex projects requiring scheduling of activities depending on other activities and/or timely allocation of resources. Adaptable to variety of complex scheduling problems in manufacturing, transportation, business, architecture, and construction.

  17. Complex matrix model duality

    Energy Technology Data Exchange (ETDEWEB)

    Brown, T.W.

    2010-11-15

    The same complex matrix model calculates both tachyon scattering for the c=1 non-critical string at the self-dual radius and certain correlation functions of half-BPS operators in N=4 super- Yang-Mills. It is dual to another complex matrix model where the couplings of the first model are encoded in the Kontsevich-like variables of the second. The duality between the theories is mirrored by the duality of their Feynman diagrams. Analogously to the Hermitian Kontsevich- Penner model, the correlation functions of the second model can be written as sums over discrete points in subspaces of the moduli space of punctured Riemann surfaces. (orig.)

  18. Nonlinear dynamics and complexity

    CERN Document Server

    Luo, Albert; Fu, Xilin

    2014-01-01

    This important collection presents recent advances in nonlinear dynamics including analytical solutions, chaos in Hamiltonian systems, time-delay, uncertainty, and bio-network dynamics. Nonlinear Dynamics and Complexity equips readers to appreciate this increasingly main-stream approach to understanding complex phenomena in nonlinear systems as they are examined in a broad array of disciplines. The book facilitates a better understanding of the mechanisms and phenomena in nonlinear dynamics and develops the corresponding mathematical theory to apply nonlinear design to practical engineering.

  19. Complex/Symplectic Mirrors

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, Wu-yen; Kachru, Shamit; /Stanford U., ITP /SLAC; Tomasiello, Alessandro; /Stanford U., ITP

    2005-10-28

    We construct a class of symplectic non-Kaehler and complex non-Kaehler string theory vacua, extending and providing evidence for an earlier suggestion by Polchinski and Strominger. The class admits a mirror pairing by construction. Comparing hints from a variety of sources, including ten-dimensional supergravity and KK reduction on SU(3)-structure manifolds, suggests a picture in which string theory extends Reid's fantasy to connect classes of both complex non-Kaehler and symplectic non-Kaehler manifolds.

  20. Complex logistics audit system

    Directory of Open Access Journals (Sweden)

    Zuzana Marková

    2010-02-01

    Full Text Available Complex logistics audit system is a tool for realization of logistical audit in the company. The current methods for logistics auditare based on “ad hok” analysis of logisticsl system. This paper describes system for complex logistics audit. It is a global diagnosticsof logistics processes and functions of enterprise. The goal of logistics audit is to provide comparative documentation for managementabout state of logistics in company and to show the potential of logistics changes in order to achieve more effective companyperformance.

  1. Simulations with complex measure

    International Nuclear Information System (INIS)

    Markham, J.K.; Kieu, T.D.

    1997-01-01

    A method is proposed to handle the sign problem in the simulation of systems having indefinite or complex-valued measures. In general, this new approach, which is based on renormalisation blocking, is shown to yield statistical errors smaller that the crude Monte Carlo method using absolute values of the original measures. The improved method is applied to the 2D Ising model with temperature generalised to take on complex values. It is also adapted to implement Monte Carlo Renormalisation Group calculations of the magnetic and thermal critical exponents. 10 refs., 4 tabs., 7 figs

  2. Qubit Complexity of Continuous Problems

    National Research Council Canada - National Science Library

    Papageorgiou, A; Traub, J. F

    2005-01-01

    .... The authors show how to obtain the classical query complexity for continuous problems. They then establish a simple formula for a lower bound on the qubit complexity in terms of the classical query complexity...

  3. Prediction of Biomolecular Complexes

    KAUST Repository

    Vangone, Anna

    2017-04-12

    Almost all processes in living organisms occur through specific interactions between biomolecules. Any dysfunction of those interactions can lead to pathological events. Understanding such interactions is therefore a crucial step in the investigation of biological systems and a starting point for drug design. In recent years, experimental studies have been devoted to unravel the principles of biomolecular interactions; however, due to experimental difficulties in solving the three-dimensional (3D) structure of biomolecular complexes, the number of available, high-resolution experimental 3D structures does not fulfill the current needs. Therefore, complementary computational approaches to model such interactions are necessary to assist experimentalists since a full understanding of how biomolecules interact (and consequently how they perform their function) only comes from 3D structures which provide crucial atomic details about binding and recognition processes. In this chapter we review approaches to predict biomolecular complexesBiomolecular complexes, introducing the concept of molecular dockingDocking, a technique which uses a combination of geometric, steric and energetics considerations to predict the 3D structure of a biological complex starting from the individual structures of its constituent parts. We provide a mini-guide about docking concepts, its potential and challenges, along with post-docking analysis and a list of related software.

  4. Real and complex analysis

    CERN Document Server

    Apelian, Christopher; Taft, Earl; Nashed, Zuhair

    2009-01-01

    The Spaces R, Rk, and CThe Real Numbers RThe Real Spaces RkThe Complex Numbers CPoint-Set Topology Bounded SetsClassification of Points Open and Closed SetsNested Intervals and the Bolzano-Weierstrass Theorem Compactness and Connectedness Limits and Convergence Definitions and First Properties Convergence Results for SequencesTopological Results for Sequences Properties of Infinite SeriesManipulations of Series in RFunctions: Definitions and Limits DefinitionsFunctions as MappingsSome Elementary Complex FunctionsLimits of FunctionsFunctions: Continuity and Convergence Continuity Uniform Continuity Sequences and Series of FunctionsThe DerivativeThe Derivative for f: D1 → RThe Derivative for f: Dk → RThe Derivative for f: Dk → RpThe Derivative for f: D → CThe Inverse and Implicit Function TheoremsReal IntegrationThe Integral of f: [a, b] → RProperties of the Riemann Integral Further Development of Integration TheoryVector-Valued and Line IntegralsComplex IntegrationIntroduction to Complex Integrals Fu...

  5. Automatic Complexity Analysis

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    1989-01-01

    One way to analyse programs is to to derive expressions for their computational behaviour. A time bound function (or worst-case complexity) gives an upper bound for the computation time as a function of the size of input. We describe a system to derive such time bounds automatically using abstract...

  6. Complexity and ecology

    International Nuclear Information System (INIS)

    Gomez Giraldo, Luis Jair

    2002-01-01

    The present article examines the transformation that the construction of the theoretical body of ecology as a science has been going through since it first appeared in the XIX century within the logic of classical science until recent developments comprised within complex systemic. Mainly departing from the analysis from thermodynamics of irreversible phenomena

  7. Supporting complex search tasks

    DEFF Research Database (Denmark)

    Gäde, Maria; Hall, Mark; Huurdeman, Hugo

    2015-01-01

    , is fragmented at best. The workshop addressed the many open research questions: What are the obvious use cases and applications of complex search? What are essential features of work tasks and search tasks to take into account? And how do these evolve over time? With a multitude of information, varying from...

  8. Managing Complex Dynamical Systems

    Science.gov (United States)

    Cox, John C.; Webster, Robert L.; Curry, Jeanie A.; Hammond, Kevin L.

    2011-01-01

    Management commonly engages in a variety of research designed to provide insight into the motivation and relationships of individuals, departments, organizations, etc. This paper demonstrates how the application of concepts associated with the analysis of complex systems applied to such data sets can yield enhanced insights for managerial action.

  9. benzimidazole metal complexes

    Indian Academy of Sciences (India)

    aUnité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, Université des Frères. Mentouri .... determine the quantum chemical parameters for the title ..... retical study of benzazole thioether and its zinc complex.

  10. COMPLEXITY AND UNIVERSITY

    Directory of Open Access Journals (Sweden)

    Edna Lemes Martins Pereira

    2013-12-01

    Full Text Available Economic globalization affects different countries on the globe, has positive effects mainly related to access to communication, which promotes the exchange of ideas, information, products and quality of life. However, extends numerous negative aspects such as marginalization, economic dependencies, political, cultural, scientific, educational accentuate social inequalities and cultural conflicts and territorial. In this article it is a dialogue with authors (Cunha 2009; BARNETT 2005; MORIN 1999, 2006, among others, who understand these changes in society from the contemporary world as conceived as the "Complexity era" or "supercomplexity". To understand and cope with this reality, they propose a paradigm that is able to overcome the fragmentation and reductionism of knowledge and to relate the multiple approaches and visions to meet the complexity of reality. Although this paper presents proposals to the aforementioned authors point to education and the university found in this tangle of interconnected global transformations, given the need to be subject to act in a complex reality that requires critical and self-critical professionals, able to think about their own ability to think, understand and act within this complex context.

  11. (VI) ML6 Complexes

    African Journals Online (AJOL)

    A geometric analysis revealed that beta-(C-H) and alpha-(C-C) can occupy the seventh and eighth coordination sites in the title Fischer carbene complexes as agostic interactions, which allows classifying the carbene as a η3 ligand in these cases. This theory was supported by the relative energies of the conformers and an ...

  12. The CERN accelerator complex

    CERN Multimedia

    Mobs, Esma Anais

    2016-01-01

    The LHC is the last ring (dark blue line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  13. The CERN accelerator complex

    CERN Multimedia

    Christiane Lefèvre

    2008-01-01

    The LHC is the last ring (dark grey line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  14. Nature, computation and complexity

    International Nuclear Information System (INIS)

    Binder, P-M; Ellis, G F R

    2016-01-01

    The issue of whether the unfolding of events in the world can be considered a computation is explored in this paper. We come to different conclusions for inert and for living systems (‘no’ and ‘qualified yes’, respectively). We suggest that physical computation as we know it exists only as a tool of complex biological systems: us. (paper)

  15. Complex Regional Pain Syndrome

    Science.gov (United States)

    Complex regional pain syndrome (CRPS) is a chronic pain condition. It causes intense pain, usually in the arms, hands, legs, or feet. It may happen ... move the affected body part The cause of CRPS is unknown. There is no specific diagnostic test. ...

  16. Prediction of Biomolecular Complexes

    KAUST Repository

    Vangone, Anna; Oliva, Romina; Cavallo, Luigi; Bonvin, Alexandre M. J. J.

    2017-01-01

    Almost all processes in living organisms occur through specific interactions between biomolecules. Any dysfunction of those interactions can lead to pathological events. Understanding such interactions is therefore a crucial step in the investigation of biological systems and a starting point for drug design. In recent years, experimental studies have been devoted to unravel the principles of biomolecular interactions; however, due to experimental difficulties in solving the three-dimensional (3D) structure of biomolecular complexes, the number of available, high-resolution experimental 3D structures does not fulfill the current needs. Therefore, complementary computational approaches to model such interactions are necessary to assist experimentalists since a full understanding of how biomolecules interact (and consequently how they perform their function) only comes from 3D structures which provide crucial atomic details about binding and recognition processes. In this chapter we review approaches to predict biomolecular complexesBiomolecular complexes, introducing the concept of molecular dockingDocking, a technique which uses a combination of geometric, steric and energetics considerations to predict the 3D structure of a biological complex starting from the individual structures of its constituent parts. We provide a mini-guide about docking concepts, its potential and challenges, along with post-docking analysis and a list of related software.

  17. COMPLEX PROMOTIONSIN RETAIL

    Directory of Open Access Journals (Sweden)

    O. Yusupova

    2015-10-01

    Full Text Available Complex promotions used by retailers introduce to the consumers several rules that must be satisfied in order to get some benefits and usually refer to multiple products (e.g. “buy two, get one free”. Rules of complex promotions can be quite sophisticated and complicated themselves. Since diversity of complex promotions limited only by marketers’ imagination we can observe broad variety of promotions’ rules and representa¬tions of those rules in retailers’ commercials. Such diversification makes no good for fellow scientist who’s trying to sort all type of promotions into the neatly organized classification. Although we can simple add every single set of rules offered by retailers as a separate form of sales promotion it seems not to be the best way of dealing with such a problem. The better way is to realize that mechanisms underlying that variety of promotions are basically the same, namely changes in demand or quantity demanded. Those two concepts alone provide powerful insight into classification of complex promotions and allow us to comprehend the variety of promotions offered by marketers nowadays.

  18. Uranyl complexes of glutathione

    Energy Technology Data Exchange (ETDEWEB)

    Marzotto, A [Consiglio Nazionale delle Ricerche, Padua (Italy). Lab. di Chimica e Tecnologia dei Radioelementi

    1977-01-01

    Dioxouranium(VI) complexes of the tripeptide glutathione having different molar ratios were prepared and studied by IR, PMR, electronic absorption and circular dichroism spectra. The results indicate that coordination occurs at the carboxylato groups, acting as monodentate ligands, whereas no significant interaction with the amino and sulfhydrylic groups takes place.

  19. Complexity and formative experiences

    Directory of Open Access Journals (Sweden)

    Roque Strieder

    2017-12-01

    Full Text Available The contemporaneity is characterized by instability and diversity calling into question certainties and truths proposed in modernity. We recognize that the reality of things and phenomena become effective as a set of events, interactions, retroactions and chances. This different frame extends the need for revision of the epistemological foundations that sustain educational practices and give them sense. The complex thinking is an alternative option for acting as a counterpoint to classical science and its reductionist logic and knowledge compartmentalization, as well as to answer to contemporary epistemological and educational challenges. It aims to associate different areas and forms of knowledge, without, however merge them, distinguishing without separating the several disciplines and instances of the realities. This study, in theoretical references, highlights the relevance of complex approaches to support formative experiences because also able to produce complexities in reflections about educational issues. We conclude that formative possibilities from complexity potentialize the resignification of human’s conception and the understanding of its singularity in interdependence; The understanding that pedagogical and educational activities is a constant interrogation about the possibilities of knowing the knowledge and reframe learning, far beyond knowing its functions and utilitarian purposes; and, as a formative possibility, places us on the trail of responsibility, not as something eventual, but present and indicative of freedom to choose to stay or go beyond.

  20. pyridine-carboxamide complexes

    Indian Academy of Sciences (India)

    of the solution was reduced by slow evaporation. The prod- uct was ... Data collection, data reduction, structure solu- ... and a selection of bond lengths and angles are shown in. Table 2. ...... Zn(II) complexes featuring a disulfide bridge and H-.

  1. Complexity driven photonics

    KAUST Repository

    Fratalocchi, Andrea

    2014-01-01

    Disorder and chaos are ubiquitous phenomena that are mostly unwanted in applications. On the contrary, they can be exploited to create a new technology. In this talk I will summarize my research in this field, discussing chaotic energy harvesting, nonlinear stochastic resonance and complex nanolasers.

  2. Unifying Complexity and Information

    Science.gov (United States)

    Ke, Da-Guan

    2013-04-01

    Complex systems, arising in many contexts in the computer, life, social, and physical sciences, have not shared a generally-accepted complexity measure playing a fundamental role as the Shannon entropy H in statistical mechanics. Superficially-conflicting criteria of complexity measurement, i.e. complexity-randomness (C-R) relations, have given rise to a special measure intrinsically adaptable to more than one criterion. However, deep causes of the conflict and the adaptability are not much clear. Here I trace the root of each representative or adaptable measure to its particular universal data-generating or -regenerating model (UDGM or UDRM). A representative measure for deterministic dynamical systems is found as a counterpart of the H for random process, clearly redefining the boundary of different criteria. And a specific UDRM achieving the intrinsic adaptability enables a general information measure that ultimately solves all major disputes. This work encourages a single framework coving deterministic systems, statistical mechanics and real-world living organisms.

  3. (II) COMPLEX COMPOUND

    African Journals Online (AJOL)

    user

    electrochemical sensors, as well as in various chromatographic ... were carried out using Jenway pH meter Model 3320 and a conductivity ... Figure 1: the proposed molecular structure of the copper (II) Schiff base complex. M = Cu (II) or Mn (II).

  4. Complexity driven photonics

    KAUST Repository

    Fratalocchi, Andrea

    2014-12-01

    Disorder and chaos are ubiquitous phenomena that are mostly unwanted in applications. On the contrary, they can be exploited to create a new technology. In this talk I will summarize my research in this field, discussing chaotic energy harvesting, nonlinear stochastic resonance and complex nanolasers.

  5. The Colletotrichum acutatum complex

    NARCIS (Netherlands)

    Damm, U.; Cannon, P.F.; Woudenberg, J.H.C.; Crous, P.W.

    2012-01-01

    Colletotrichum acutatum is known as an important anthracnose pathogen of a wide range of host plants worldwide. Numerous studies have reported subgroups within the C. acutatum species complex. Multilocus molecular phylogenetic analysis (ITS, ACT, TUB2, CHS-1, GAPDH, HIS3) of 331 strains previously

  6. Architecture of Intermodal Complex

    NARCIS (Netherlands)

    Lee, S.; Herneoja, Aulikki; Österlund, Toni; Markkanen, Piia

    This paper focuses on the conception and design of architecture as the work of producing media about buildings and other environmental artifacts. I approach
    the questions regarding simplicity and complexity through "interdependence" and "intermodality." I believe the two concepts offer more

  7. unsymmetrical Schiff base complexes

    Indian Academy of Sciences (India)

    the effect of the substitutional groups of the Schiff base on the oxidation and reduction potentials, we used ... Electrochemistry of these complexes showed that the presence of electron .... a solution of the ligand (1 mmol) in methanol (15 mL).

  8. Management of complex fisheries

    DEFF Research Database (Denmark)

    Frost, Hans Staby; Andersen, Peder; Hoff, Ayoe

    2013-01-01

    , including taking into account the response of the fishermen to implemented management measures. To demonstrate the use of complex management models this paper assesses a number of second best management schemes against a first rank optimum (FRO), an ideal individual transferable quotas (ITQ) system...

  9. Herding Complex Networks

    KAUST Repository

    Ruf, Sebastian F.; Egersted, Magnus; Shamma, Jeff S.

    2018-01-01

    the ability to drive a system to a specific set in the state space, was recently introduced as an alternative network control notion. This paper considers the application of herdability to the study of complex networks. The herdability of a class of networked

  10. The hamstring muscle complex

    NARCIS (Netherlands)

    van der Made, A. D.; Wieldraaijer, T.; Kerkhoffs, G. M.; Kleipool, R. P.; Engebretsen, L.; van Dijk, C. N.; Golanó, P.

    2015-01-01

    The anatomical appearance of the hamstring muscle complex was studied to provide hypotheses for the hamstring injury pattern and to provide reference values of origin dimensions, muscle length, tendon length, musculotendinous junction (MTJ) length as well as width and length of a tendinous

  11. Symmetry in Complex Networks

    Directory of Open Access Journals (Sweden)

    Angel Garrido

    2011-01-01

    Full Text Available In this paper, we analyze a few interrelated concepts about graphs, such as their degree, entropy, or their symmetry/asymmetry levels. These concepts prove useful in the study of different types of Systems, and particularly, in the analysis of Complex Networks. A System can be defined as any set of components functioning together as a whole. A systemic point of view allows us to isolate a part of the world, and so, we can focus on those aspects that interact more closely than others. Network Science analyzes the interconnections among diverse networks from different domains: physics, engineering, biology, semantics, and so on. Current developments in the quantitative analysis of Complex Networks, based on graph theory, have been rapidly translated to studies of brain network organization. The brain's systems have complex network features—such as the small-world topology, highly connected hubs and modularity. These networks are not random. The topology of many different networks shows striking similarities, such as the scale-free structure, with the degree distribution following a Power Law. How can very different systems have the same underlying topological features? Modeling and characterizing these networks, looking for their governing laws, are the current lines of research. So, we will dedicate this Special Issue paper to show measures of symmetry in Complex Networks, and highlight their close relation with measures of information and entropy.

  12. Light in complex dielectrics

    NARCIS (Netherlands)

    Schuurmans, F.J.P.

    1999-01-01

    In this thesis the properties of light in complex dielectrics are described, with the two general topics of "modification of spontaneous emission" and "Anderson localization of light". The first part focuses on the spontaneous emission rate of an excited atom in a dielectric host with variable

  13. Typical Complexity Numbers

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Typical Complexity Numbers. Say. 1000 tones,; 100 Users,; Transmission every 10 msec. Full Crosstalk cancellation would require. Full cancellation requires a matrix multiplication of order 100*100 for all the tones. 1000*100*100*100 operations every second for the ...

  14. Life: Complexity and Diversity

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 4. Life : Complexity and Diversity Growing Larger. Madhav Gadgil. Series Article Volume 1 Issue 4 April 1996 pp 15-22. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/001/04/0015-0022 ...

  15. The CERN accelerator complex

    CERN Multimedia

    Haffner, Julie

    2013-01-01

    The LHC is the last ring (dark grey line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  16. Complexity measures of music

    Science.gov (United States)

    Pease, April; Mahmoodi, Korosh; West, Bruce J.

    2018-03-01

    We present a technique to search for the presence of crucial events in music, based on the analysis of the music volume. Earlier work on this issue was based on the assumption that crucial events correspond to the change of music notes, with the interesting result that the complexity index of the crucial events is mu ~ 2, which is the same inverse power-law index of the dynamics of the brain. The search technique analyzes music volume and confirms the results of the earlier work, thereby contributing to the explanation as to why the brain is sensitive to music, through the phenomenon of complexity matching. Complexity matching has recently been interpreted as the transfer of multifractality from one complex network to another. For this reason we also examine the mulifractality of music, with the observation that the multifractal spectrum of a computer performance is significantly narrower than the multifractal spectrum of a human performance of the same musical score. We conjecture that although crucial events are demonstrably important for information transmission, they alone are not suficient to define musicality, which is more adequately measured by the multifractality spectrum.

  17. Complexes Tickling the $ubject

    Directory of Open Access Journals (Sweden)

    Matthew Gildersleeve

    2016-11-01

    Full Text Available This article continues my earlier work of reading Jung with Lacan. This article will develop Zizek’s work on Lacan’s concept of objet petit a by relating it to a phenomenological interpretation of Jung. I use a number of different examples, including Zizek’s interpretation of Francis Bacon, Edvard Munch, Hans Holbein and Johann Gottlieb Fichte, to describe the objet petit a and its relationship to a phenomenological interpretation of complexes. By integrating other Lacanian concepts, such as subject, drive, fantasy, jouissance, gaze, desire, and ego as well as the imaginary, symbolic and Real, this work also highlights how Hegel and Heidegger can elucidate the relationship between objet petit a and complexes. Jung’s transcendent function and the Rosarium Philosophorum also elucidate the relationship between Jung and Lacan.

  18. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...

  19. THO/TREX complex

    KAUST Repository

    Dö ll, Stefanie; Kuhlmann, Markus; Rutten, Twan; Mette, Michael F.; Scharfenberg, Sarah; Petridis, Antonios; Berreth, Dorothee-Carina; Mock, Hans-Peter

    2017-01-01

    Secondary metabolites are involved in the plant stress response. Among these are scopolin and its active form scopoletin, which are coumarin derivatives associated with reactive oxygen species scavenging and pathogen defence. Here we show that scopolin accumulation can be induced in the root by osmotic stress and in the leaf by low-temperature stress in Arabidopsis thaliana. A genetic screen for altered scopolin levels in A. thaliana revealed a mutant compromised in scopolin accumulation in response to stress; the lesion was present in a homologue of THO1 coding for a subunit of the THO/TREX complex. The THO/TREX complex contributes to RNA silencing, supposedly by trafficking precursors of small RNAs. Mutants defective in THO, AGO1, SDS3 and RDR6 were impaired with respect to scopolin accumulation in response to stress, suggesting a mechanism based on RNA silencing such as the trans-acting small interfering RNA pathway, which requires THO/TREX function.

  20. Complexity is simple!

    Science.gov (United States)

    Cottrell, William; Montero, Miguel

    2018-02-01

    In this note we investigate the role of Lloyd's computational bound in holographic complexity. Our goal is to translate the assumptions behind Lloyd's proof into the bulk language. In particular, we discuss the distinction between orthogonalizing and `simple' gates and argue that these notions are useful for diagnosing holographic complexity. We show that large black holes constructed from series circuits necessarily employ simple gates, and thus do not satisfy Lloyd's assumptions. We also estimate the degree of parallel processing required in this case for elementary gates to orthogonalize. Finally, we show that for small black holes at fixed chemical potential, the orthogonalization condition is satisfied near the phase transition, supporting a possible argument for the Weak Gravity Conjecture first advocated in [1].

  1. The medial patellofemoral complex.

    Science.gov (United States)

    Loeb, Alexander E; Tanaka, Miho J

    2018-06-01

    The purpose of this review is to describe the current understanding of the medial patellofemoral complex, including recent anatomic advances, evaluation of indications for reconstruction with concomitant pathology, and surgical reconstruction techniques. Recent advances in our understanding of MPFC anatomy have found that there are fibers that insert onto the deep quadriceps tendon as well as the patella, thus earning the name "medial patellofemoral complex" to allow for the variability in its anatomy. In MPFC reconstruction, anatomic origin and insertion points and appropriate graft length are critical to prevent overconstraint of the patellofemoral joint. The MPFC is a crucial soft tissue checkrein to lateral patellar translation, and its repair or reconstruction results in good restoration of patellofemoral stability. As our understanding of MPFC anatomy evolves, further studies are needed to apply its relevance in kinematics and surgical applications to its role in maintaining patellar stability.

  2. Polystochastic Models for Complexity

    CERN Document Server

    Iordache, Octavian

    2010-01-01

    This book is devoted to complexity understanding and management, considered as the main source of efficiency and prosperity for the next decades. Divided into six chapters, the book begins with a presentation of basic concepts as complexity, emergence and closure. The second chapter looks to methods and introduces polystochastic models, the wave equation, possibilities and entropy. The third chapter focusing on physical and chemical systems analyzes flow-sheet synthesis, cyclic operations of separation, drug delivery systems and entropy production. Biomimetic systems represent the main objective of the fourth chapter. Case studies refer to bio-inspired calculation methods, to the role of artificial genetic codes, neural networks and neural codes for evolutionary calculus and for evolvable circuits as biomimetic devices. The fifth chapter, taking its inspiration from systems sciences and cognitive sciences looks to engineering design, case base reasoning methods, failure analysis, and multi-agent manufacturing...

  3. Rhodium thioacetate complexes

    International Nuclear Information System (INIS)

    Baranovskij, I.B.; Golubnichaya, M.A.; Mazo, G.Ya.

    1976-01-01

    Thioacetato-complexes of rhodium(II) were prepared by the reaction of thioacetic acid with rhodium(II) carboxylates. Diamagnetic compounds of the type Rh 2 (CH 3 COS) 4 2A, where A=H 2 O, Py, N 2 H 4 .HCl, Thio, KNCS, DMSO, CH 3 CN, CsCl, or CH 3 COSH, were isolated. Their infrared spectra were recorded, and the principal vibrational wavenumbers assigned. The X-ray electron spectra confirm that rhodium is divalent. The thioacetato-complexes are dimeric, with a metal-metal bond. [Rh(NH 3 ) 5 (CH 3 COS)]I 2 was prepared, and its properties studied. The significant decrease in the strength of the bonds formed by the axial ligands with rhodium is due to the strong trans-influence of the covalent rhodium-rhodium sigma-bond

  4. Complex conductivity of soils

    DEFF Research Database (Denmark)

    Revil, A.; Coperey, A.; Shao, Z.

    2017-01-01

    The complex conductivity of soil remains poorly known despite the growing importance of this method in hyrogeophysics. In order to fill this gap of knowledge, we investigate the complex conductivity of 71 soils samples (including 4 peat samples) and one clean sand in the frequency range 0.1 Hertz...... to 45 kHz. The soil samples are saturated with 6 different NaCl brines with conductivities (0.031, 0.53, 1.15, 5.7, 14.7, and 22 S m-1, NaCl, 25°C) in order to determine their intrinsic formation factor and surface conductivity. This dataset is used to test the predictions of the dynamic Stern...

  5. Modeling Complex Systems

    International Nuclear Information System (INIS)

    Schreckenberg, M

    2004-01-01

    This book by Nino Boccara presents a compilation of model systems commonly termed as 'complex'. It starts with a definition of the systems under consideration and how to build up a model to describe the complex dynamics. The subsequent chapters are devoted to various categories of mean-field type models (differential and recurrence equations, chaos) and of agent-based models (cellular automata, networks and power-law distributions). Each chapter is supplemented by a number of exercises and their solutions. The table of contents looks a little arbitrary but the author took the most prominent model systems investigated over the years (and up until now there has been no unified theory covering the various aspects of complex dynamics). The model systems are explained by looking at a number of applications in various fields. The book is written as a textbook for interested students as well as serving as a comprehensive reference for experts. It is an ideal source for topics to be presented in a lecture on dynamics of complex systems. This is the first book on this 'wide' topic and I have long awaited such a book (in fact I planned to write it myself but this is much better than I could ever have written it!). Only section 6 on cellular automata is a little too limited to the author's point of view and one would have expected more about the famous Domany-Kinzel model (and more accurate citation!). In my opinion this is one of the best textbooks published during the last decade and even experts can learn a lot from it. Hopefully there will be an actualization after, say, five years since this field is growing so quickly. The price is too high for students but this, unfortunately, is the normal case today. Nevertheless I think it will be a great success! (book review)

  6. On convex complexity measures

    Czech Academy of Sciences Publication Activity Database

    Hrubeš, P.; Jukna, S.; Kulikov, A.; Pudlák, Pavel

    2010-01-01

    Roč. 411, 16-18 (2010), s. 1842-1854 ISSN 0304-3975 R&D Projects: GA AV ČR IAA1019401 Institutional research plan: CEZ:AV0Z10190503 Keywords : boolean formula * complexity measure * combinatorial rectangle * convexity Subject RIV: BA - General Mathematics Impact factor: 0.838, year: 2010 http://www.sciencedirect.com/science/article/pii/S0304397510000885

  7. Complexity in Dynamical Systems

    Science.gov (United States)

    Moore, Cristopher David

    The study of chaos has shown us that deterministic systems can have a kind of unpredictability, based on a limited knowledge of their initial conditions; after a finite time, the motion appears essentially random. This observation has inspired a general interest in the subject of unpredictability, and more generally, complexity; how can we characterize how "complex" a dynamical system is?. In this thesis, we attempt to answer this question with a paradigm of complexity that comes from computer science, we extract sets of symbol sequences, or languages, from a dynamical system using standard methods of symbolic dynamics; we then ask what kinds of grammars or automata are needed a generate these languages. This places them in the Chomsky heirarchy, which in turn tells us something about how subtle and complex the dynamical system's behavior is. This gives us insight into the question of unpredictability, since these automata can also be thought of as computers attempting to predict the system. In the culmination of the thesis, we find a class of smooth, two-dimensional maps which are equivalent to the highest class in the Chomsky heirarchy, the turning machine; they are capable of universal computation. Therefore, these systems possess a kind of unpredictability qualitatively different from the usual "chaos": even if the initial conditions are known exactly, questions about the system's long-term dynamics are undecidable. No algorithm exists to answer them. Although this kind of unpredictability has been discussed in the context of distributed, many-degree-of -freedom systems (for instance, cellular automata) we believe this is the first example of such phenomena in a smooth, finite-degree-of-freedom system.

  8. Complex Business Negotiation

    OpenAIRE

    Lindholst, Morten

    2015-01-01

    Most scholars agree that engaging in preparation and planning is key to a negotiation’s effectiveness but research has largely focused solely on what happens at the negotiation table, rather than in preparation for it. This thesis addresses the balance by clarifying which preparation and planning activities are undertaken to conduct a complex business negotiation. It examines not only what activities are conducted, but also by whom, and when. One important question for both pra...

  9. Volatile uranyl hexafluoroacetoacetonate complexes

    International Nuclear Information System (INIS)

    Dines, M.B.; Hall, R.B.; Kaldor, A.; Kramer, G.M.; Maas, E.T. Jr.

    1980-01-01

    A composition of matter is described, characterized by the formula UO 2 (CF 3 COCHCOCF 3 ).L where L is a ligand selected from isopropanol, ethanol, isobutanol, tert-butanol, methanol, tetrahydrofuran, acetone, dimethylformamide, n-propanol and ethyl acetate. A process for producing the complex comprises reacting uranyl chloride with a hexafluoroacetylacetonate dissolved in a ligand L: experimental details are given. (U.K.)

  10. Operational Shock Complexity Theory

    Science.gov (United States)

    2005-05-26

    Theory : Recommendations For The National Strategy To Defeat Terrorism.” Student Issue Paper, Center for Strategic Leadership , US Army War College, July...Lens of Complexity Theory : Recommendations For The National Strategy To Defeat Terrorism.” (Student Issue Paper, Center for Strategic Leadership , US...planners managed to cause confusion in the enemy’s internal model by operating in an unexpected manner. 140 Glenn E. James, “Chaos Theory : The

  11. Engineering Complex Tissues

    Science.gov (United States)

    MIKOS, ANTONIOS G.; HERRING, SUSAN W.; OCHAREON, PANNEE; ELISSEEFF, JENNIFER; LU, HELEN H.; KANDEL, RITA; SCHOEN, FREDERICK J.; TONER, MEHMET; MOONEY, DAVID; ATALA, ANTHONY; VAN DYKE, MARK E.; KAPLAN, DAVID; VUNJAK-NOVAKOVIC, GORDANA

    2010-01-01

    This article summarizes the views expressed at the third session of the workshop “Tissue Engineering—The Next Generation,” which was devoted to the engineering of complex tissue structures. Antonios Mikos described the engineering of complex oral and craniofacial tissues as a “guided interplay” between biomaterial scaffolds, growth factors, and local cell populations toward the restoration of the original architecture and function of complex tissues. Susan Herring, reviewing osteogenesis and vasculogenesis, explained that the vascular arrangement precedes and dictates the architecture of the new bone, and proposed that engineering of osseous tissues might benefit from preconstruction of an appropriate vasculature. Jennifer Elisseeff explored the formation of complex tissue structures based on the example of stratified cartilage engineered using stem cells and hydrogels. Helen Lu discussed engineering of tissue interfaces, a problem critical for biological fixation of tendons and ligaments, and the development of a new generation of fixation devices. Rita Kandel discussed the challenges related to the re-creation of the cartilage-bone interface, in the context of tissue engineered joint repair. Frederick Schoen emphasized, in the context of heart valve engineering, the need for including the requirements derived from “adult biology” of tissue remodeling and establishing reliable early predictors of success or failure of tissue engineered implants. Mehmet Toner presented a review of biopreservation techniques and stressed that a new breakthrough in this field may be necessary to meet all the needs of tissue engineering. David Mooney described systems providing temporal and spatial regulation of growth factor availability, which may find utility in virtually all tissue engineering and regeneration applications, including directed in vitro and in vivo vascularization of tissues. Anthony Atala offered a clinician’s perspective for functional tissue

  12. Complex geometries in wood

    DEFF Research Database (Denmark)

    Tamke, Martin; Ramsgaard Thomsen, Mette; Riiber Nielsen, Jacob

    2009-01-01

    The versatility of wood constructions and traditional wood joints for the production of non standard elements was in focus of a design based research. Herein we established a seamless process from digital design to fabrication. A first research phase centered on the development of a robust...... parametric model and a generic design language a later explored the possibilities to construct complex shaped geometries with self registering joints on modern wood crafting machines. The research was carried out as collaboration with industrial partners....

  13. Fluorido complexes of technetium

    International Nuclear Information System (INIS)

    Mariappan Balasekaran, Samundeeswari

    2013-01-01

    Fluorine chemistry has received considerable interest during recent years due to its significant role in the life sciences, especially for drug development. Despite the great nuclear medicinal importance of the radioactive metal technetium in radiopharmaceuticals, its coordination chemistry with the fluorido ligand is by far less explored than that of other ligands. Up to now, only a few technetium fluorides are known. This thesis contains the synthesis, spectroscopic and structural characterization of novel technetium fluorides in the oxidation states ''+1'', ''+2'', ''+4'' and ''+6''. In the oxidation state ''+6'', the fluoridotechnetates were synthesized either from nitridotechnetic(VI) acid or from pertechnetate by using reducing agent and have been isolated as cesium or tetraethylammonium salts. The compounds were characterized spectroscopically and structurally. In the intermediate oxidation state ''+4'', hexafluoridotechnetate(IV) was known for long time and studied spectroscopically. This thesis reports novel and improved syntheses and solved the critical issues of early publications such as the color, some spectroscopic properties and the structure of this key compound. Single crystal analyses of alkali metal, ammonium and tetramethylammonium salts of hexafluoridotechnetate(IV) are presented. In aqueous alkaline solutions, the ammonium salt of hexafluoridotechnetate(IV) undergoes hydrolysis and forms an oxido-bridged dimeric complex. It is the first step hydrolysis product of hexafluoridotechnetate(IV) and was characterized by spectroscopic and crystallographic methods. Low-valent technetium fluorides with the metal in the oxidation states of ''+2'' or ''+1'' are almost unknown. A detailed description of the synthesis and characterization of pentafluoridonitrosyltechnetate(II) is presented. The complex was isolated as alkali metal salts, and spectroscopic as well as structural features of the complexes are presented. Different salts of the trans

  14. Arithmetic of Complex Manifolds

    CERN Document Server

    Lange, Herbert

    1989-01-01

    It was the aim of the Erlangen meeting in May 1988 to bring together number theoretists and algebraic geometers to discuss problems of common interest, such as moduli problems, complex tori, integral points, rationality questions, automorphic forms. In recent years such problems, which are simultaneously of arithmetic and geometric interest, have become increasingly important. This proceedings volume contains 12 original research papers. Its main topics are theta functions, modular forms, abelian varieties and algebraic three-folds.

  15. Complex concentrate pretreatment

    International Nuclear Information System (INIS)

    Lokken, R.O.; Scheele, R.D.; Strachan, D.M.; Toste, A.P.

    1991-03-01

    After removal of the transuranics (TRU) by the TRUEX process, complex concentrate waste will be grouted for final storage. The purpose of this project, conducted at the Pacific Northwest Laboratory, is to support a future decision to grout the complexant waste without destruction of the organic contents. It has been demonstrated that grouts with acceptable parameters for the Transportable Grout Facility can be made using actual waste. The acceptability of these grouts from a regulatory view seems to be less of a problem than previously. None of the organics found in the waste have been found on the EPA hazardous chemicals list. Two potential problems with the processing of the complex concentrate wastes were identified during the use of the TRUEX process on samples of several milliliters. One was the amount of foam that is generated during acid addition to the alkaline waste. Some of this foam appears to be of a waxy nature but does redissolve when the waste is strongly acid. The second potential problem is that noticeable amounts of NO x gases are generated. No quantitative measure of the NO x gas generation was made. The problem relates to processing the waste in B-plant where there are no facilities to handle NO x gases. 5 refs., 4 figs., 4 tabs

  16. Predictive Surface Complexation Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Sverjensky, Dimitri A. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Earth and Planetary Sciences

    2016-11-29

    Surface complexation plays an important role in the equilibria and kinetics of processes controlling the compositions of soilwaters and groundwaters, the fate of contaminants in groundwaters, and the subsurface storage of CO2 and nuclear waste. Over the last several decades, many dozens of individual experimental studies have addressed aspects of surface complexation that have contributed to an increased understanding of its role in natural systems. However, there has been no previous attempt to develop a model of surface complexation that can be used to link all the experimental studies in order to place them on a predictive basis. Overall, my research has successfully integrated the results of the work of many experimentalists published over several decades. For the first time in studies of the geochemistry of the mineral-water interface, a practical predictive capability for modeling has become available. The predictive correlations developed in my research now enable extrapolations of experimental studies to provide estimates of surface chemistry for systems not yet studied experimentally and for natural and anthropogenically perturbed systems.

  17. Control of complex systems

    CERN Document Server

    Albertos, Pedro; Blanke, Mogens; Isidori, Alberto; Schaufelberger, Walter; Sanz, Ricardo

    2001-01-01

    The world of artificial systems is reaching complexity levels that es­ cape human understanding. Surface traffic, electricity distribution, air­ planes, mobile communications, etc. , are examples that demonstrate that we are running into problems that are beyond classical scientific or engi­ neering knowledge. There is an ongoing world-wide effort to understand these systems and develop models that can capture its behavior. The reason for this work is clear, if our lack of understanding deepens, we will lose our capability to control these systems and make they behave as we want. Researchers from many different fields are trying to understand and develop theories for complex man-made systems. This book presents re­ search from the perspective of control and systems theory. The book has grown out of activities in the research program Control of Complex Systems (COSY). The program has been sponsored by the Eu­ ropean Science Foundation (ESF) which for 25 years has been one of the leading players in stimula...

  18. [VGKC-complex antibodies].

    Science.gov (United States)

    Watanabe, Osamu

    2013-04-01

    Various antibodies are associated with voltage-gated potassium channels (VGKCs). Representative antibodies to VGKCs were first identified by radioimmunoassays using radioisotope-labeled alpha-dendrotoxin-VGKCs solubilized from rabbit brain. These antibodies were detected only in a proportion of patients with acquired neuromyotonia (Isaacs' syndrome). VGKC antibodies were also detected in patients with Morvan's syndrome and in those with a form of autoimmune limbic encephalitis. Recent studies indicated that the "VGKC" antibodies are mainly directed toward associated proteins (for example LGI-1 and CASPR-2) that complex with the VGKCs themselves. The "VGKC" antibodies are now commonly known as VGKC-complex antibodies. In general, LGI-1 antibodies are most commonly detected in patients with limbic encephalitis with syndrome of inappropriate secretion of antidiuretic hormone. CASPR-2 antibodies are present in the majority of patients with Morvan's syndrome. These patients develop combinations of CNS symptoms, autonomic dysfunction, and peripheral nerve hyperexcitability. Furthermore, VGKC-complex antibodies are tightly associated with chronic idiopathic pain. Hyperexcitability of nociceptive pathways has also been implicated. These antibodies may be detected in sera of some patients with neurodegenerative diseases (for example, amyotrophic lateral sclerosis and Creutzfeldt-Jakob disease).

  19. [Complex posttraumatic stress disorder].

    Science.gov (United States)

    Green, Tamar; Kotler, Moshe

    2007-11-01

    The characteristic symptoms resulting from exposure to an extreme trauma include three clusters of symptoms: persistent experience of the traumatic event, persistent avoidance of stimuli associated with the trauma and persistent symptoms of increased arousal. Beyond the accepted clusters of symptoms for posttraumatic stress disorder exists a formation of symptoms related to exposure to extreme or prolonged stress e.g. childhood abuse, physical violence, rape, and confinement within a concentration camp. With accumulated evidence of the existence of these symptoms began a trail to classify a more complex syndrome, which included, but was not confined to the symptoms of posttraumatic stress disorder. This review addresses several subjects for study in complex posttraumatic stress disorder, which is a complicated and controversial topic. Firstly, the concept of complex posttraumatic stress disorder is presented. Secondly, the professional literature relevant to this disturbance is reviewed and finally, the authors present the polemic being conducted between the researchers of posttraumatic disturbances regarding validity, reliability and the need for separate diagnosis for these symptoms.

  20. Crystal structure of the Xpo1p nuclear export complex bound to the SxFG/PxFG repeats of the nucleoporin Nup42p.

    Science.gov (United States)

    Koyama, Masako; Hirano, Hidemi; Shirai, Natsuki; Matsuura, Yoshiyuki

    2017-10-01

    Xpo1p (yeast CRM1) is the major nuclear export receptor that carries a plethora of proteins and ribonucleoproteins from the nucleus to cytoplasm. The passage of the Xpo1p nuclear export complex through nuclear pore complexes (NPCs) is facilitated by interactions with nucleoporins (Nups) containing extensive repeats of phenylalanine-glycine (so-called FG repeats), although the precise role of each Nup in the nuclear export reaction remains incompletely understood. Here we report structural and biochemical characterization of the interactions between the Xpo1p nuclear export complex and the FG repeats of Nup42p, a nucleoporin localized at the cytoplasmic face of yeast NPCs and has characteristic SxFG/PxFG sequence repeat motif. The crystal structure of Xpo1p-PKI-Nup42p-Gsp1p-GTP complex identified three binding sites for the SxFG/PxFG repeats on HEAT repeats 14-20 of Xpo1p. Mutational analyses of Nup42p showed that the conserved serines and prolines in the SxFG/PxFG repeats contribute to Xpo1p-Nup42p binding. Our structural and biochemical data suggest that SxFG/PxFG-Nups such as Nup42p and Nup159p at the cytoplasmic face of NPCs provide high-affinity docking sites for the Xpo1p nuclear export complex in the terminal stage of NPC passage and that subsequent disassembly of the nuclear export complex facilitates recycling of free Xpo1p back to the nucleus. © 2017 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

  1. Complexity Leadership: A Theoretical Perspective

    Science.gov (United States)

    Baltaci, Ali; Balci, Ali

    2017-01-01

    Complex systems are social networks composed of interactive employees interconnected through collaborative, dynamic ties such as shared goals, perspectives and needs. Complex systems are largely based on "the complex system theory". The complex system theory focuses mainly on finding out and developing strategies and behaviours that…

  2. Cdt1 revisited: complex and tight regulation during the cell cycle and consequences of deregulation in mammalian cells

    Directory of Open Access Journals (Sweden)

    Fujita Masatoshi

    2006-10-01

    Full Text Available Abstract In eukaryotic cells, replication of genomic DNA initiates from multiple replication origins distributed on multiple chromosomes. To ensure that each origin is activated precisely only once during each S phase, a system has evolved which features periodic assembly and disassembly of essential pre-replication complexes (pre-RCs at replication origins. The pre-RC assembly reaction involves the loading of a presumptive replicative helicase, the MCM2-7 complexes, onto chromatin by the origin recognition complex (ORC and two essential factors, CDC6 and Cdt1. The eukaryotic cell cycle is driven by the periodic activation and inactivation of cyclin-dependent kinases (Cdks and assembly of pre-RCs can only occur during the low Cdk activity period from late mitosis through G1 phase, with inappropriate re-assembly suppressed during S, G2, and M phases. It was originally suggested that inhibition of Cdt1 function after S phase in vertebrate cells is due to geminin binding and that Cdt1 hyperfunction resulting from Cdt1-geminin imbalance induces re-replication. However, recent progress has revealed that Cdt1 activity is more strictly regulated by two other mechanisms in addition to geminin: (1 functional and SCFSkp2-mediated proteolytic regulation through phosphorylation by Cdks; and (2 replication-coupled proteolysis mediated by the Cullin4-DDB1Cdt2 ubiquitin ligase and PCNA, an eukaryotic sliding clamp stimulating replicative DNA polymerases. The tight regulation implies that Cdt1 control is especially critical for the regulation of DNA replication in mammalian cells. Indeed, Cdt1 overexpression evokes chromosomal damage even without re-replication. Furthermore, deregulated Cdt1 induces chromosomal instability in normal human cells. Since Cdt1 is overexpressed in cancer cells, this could be a new molecular mechanism leading to carcinogenesis. In this review, recent insights into Cdt1 function and regulation in mammalian cells are discussed.

  3. Complex Neutrosophic Subsemigroups and Ideals

    Directory of Open Access Journals (Sweden)

    Muhammad Gulistan

    2018-01-01

    Full Text Available In this article we study the idea of complex neutrosophic subsemigroups. We define the Cartesian product of complex neutrosophic subsemigroups, give some examples and study some of its related results. We also define complex neutrosophic (left, right, interior ideal in semigroup. Furthermore, we introduce the concept of characteristic function of complex neutrosophic sets, direct product of complex neutrosophic sets and study some results prove on its.

  4. Transition Complexity of Incomplete DFAs

    Directory of Open Access Journals (Sweden)

    Yuan Gao

    2010-08-01

    Full Text Available In this paper, we consider the transition complexity of regular languages based on the incomplete deterministic finite automata. A number of results on Boolean operations have been obtained. It is shown that the transition complexity results for union and complementation are very different from the state complexity results for the same operations. However, for intersection, the transition complexity result is similar to that of state complexity.

  5. LUBAC-Recruited CYLD and A20 Regulate Gene Activation and Cell Death by Exerting Opposing Effects on Linear Ubiquitin in Signaling Complexes

    Directory of Open Access Journals (Sweden)

    Peter Draber

    2015-12-01

    Full Text Available Ubiquitination and deubiquitination are crucial for assembly and disassembly of signaling complexes. LUBAC-generated linear (M1 ubiquitin is important for signaling via various immune receptors. We show here that the deubiquitinases CYLD and A20, but not OTULIN, are recruited to the TNFR1- and NOD2-associated signaling complexes (TNF-RSC and NOD2-SC, at which they cooperate to limit gene activation. Whereas CYLD recruitment depends on its interaction with LUBAC, but not on LUBAC’s M1-chain-forming capacity, A20 recruitment requires this activity. Intriguingly, CYLD and A20 exert opposing effects on M1 chain stability in the TNF-RSC and NOD2-SC. While CYLD cleaves M1 chains, and thereby sensitizes cells to TNF-induced death, A20 binding to them prevents their removal and, consequently, inhibits cell death. Thus, CYLD and A20 cooperatively restrict gene activation and regulate cell death via their respective activities on M1 chains. Hence, the interplay between LUBAC, M1-ubiquitin, CYLD, and A20 is central for physiological signaling through innate immune receptors.

  6. pH Sensing Properties of Flexible, Bias-Free Graphene Microelectrodes in Complex Fluids: From Phosphate Buffer Solution to Human Serum.

    Science.gov (United States)

    Ping, Jinglei; Blum, Jacquelyn E; Vishnubhotla, Ramya; Vrudhula, Amey; Naylor, Carl H; Gao, Zhaoli; Saven, Jeffery G; Johnson, Alan T Charlie

    2017-08-01

    Advances in techniques for monitoring pH in complex fluids can have a significant impact on analytical and biomedical applications. This study develops flexible graphene microelectrodes (GEs) for rapid (pH of complex biofluids by measuring real-time Faradaic charge transfer between the GE and a solution at zero electrical bias. For an idealized sample of phosphate buffer solution (PBS), the Faradaic current is varied monotonically and systematically with the pH, with a resolution of ≈0.2 pH unit. The current-pH dependence is well described by a hybrid analytical-computational model, where the electric double layer derives from an intrinsic, pH-independent (positive) charge associated with the graphene-water interface and ionizable (negative) charged groups. For ferritin solution, the relative Faradaic current, defined as the difference between the measured current response and a baseline response due to PBS, shows a strong signal associated with ferritin disassembly and the release of ferric ions at pH ≈2.0. For samples of human serum, the Faradaic current shows a reproducible rapid (pH. By combining the Faradaic current and real-time current variation, the methodology is potentially suitable for use to detect tumor-induced changes in extracellular pH. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. The Stigma Complex

    Science.gov (United States)

    Pescosolido, Bernice A.; Martin, Jack K.

    2016-01-01

    Since the beginning of the twenty-first century, research on stigma has continued. Building on conceptual and empirical work, the recent period clarifies new types of stigmas, expansion of measures, identification of new directions, and increasingly complex levels. Standard beliefs have been challenged, the relationship between stigma research and public debates reconsidered, and new scientific foundations for policy and programs suggested. We begin with a summary of the most recent Annual Review articles on stigma, which reminded sociologists of conceptual tools, informed them of developments from academic neighbors, and claimed findings from the early period of “resurgence.” Continued (even accelerated) progress has also revealed a central problem. Terms and measures are often used interchangeably, leading to confusion and decreasing accumulated knowledge. Drawing from this work but focusing on the past 14 years of stigma research (including mental illness, sexual orientation, HIV/AIDS, and race/ethnicity), we provide a theoretical architecture of concepts (e.g., prejudice, experienced/received discrimination), drawn together through a stigma process (i.e., stigmatization), based on four theoretical premises. Many characteristics of the mark (e.g., discredited, concealable) and variants (i.e., stigma types and targets) become the focus of increasingly specific and multidimensional definitions. Drawing from complex and systems science, we propose a stigma complex, a system of interrelated, heterogeneous parts bringing together insights across disciplines to provide a more realistic and complicated sense of the challenge facing research and change efforts. The Framework Integrating Normative Influences on Stigma (FINIS) offers a multilevel approach that can be tailored to stigmatized statuses. Finally, we outline challenges for the next phase of stigma research, with the goal of continuing scientific activity that enhances our understanding of stigma and builds

  8. Organization of complex networks

    Science.gov (United States)

    Kitsak, Maksim

    Many large complex systems can be successfully analyzed using the language of graphs and networks. Interactions between the objects in a network are treated as links connecting nodes. This approach to understanding the structure of networks is an important step toward understanding the way corresponding complex systems function. Using the tools of statistical physics, we analyze the structure of networks as they are found in complex systems such as the Internet, the World Wide Web, and numerous industrial and social networks. In the first chapter we apply the concept of self-similarity to the study of transport properties in complex networks. Self-similar or fractal networks, unlike non-fractal networks, exhibit similarity on a range of scales. We find that these fractal networks have transport properties that differ from those of non-fractal networks. In non-fractal networks, transport flows primarily through the hubs. In fractal networks, the self-similar structure requires any transport to also flow through nodes that have only a few connections. We also study, in models and in real networks, the crossover from fractal to non-fractal networks that occurs when a small number of random interactions are added by means of scaling techniques. In the second chapter we use k-core techniques to study dynamic processes in networks. The k-core of a network is the network's largest component that, within itself, exhibits all nodes with at least k connections. We use this k-core analysis to estimate the relative leadership positions of firms in the Life Science (LS) and Information and Communication Technology (ICT) sectors of industry. We study the differences in the k-core structure between the LS and the ICT sectors. We find that the lead segment (highest k-core) of the LS sector, unlike that of the ICT sector, is remarkably stable over time: once a particular firm enters the lead segment, it is likely to remain there for many years. In the third chapter we study how

  9. Magnox waste storage complex

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    This article looks at the design and construction of British Nuclear Fuel Limited's (BNFL) Magnox waste storage complex by Costain Engineering Limited. Magnox swarf from fuel decanning is stored underwater in specially designed silos. Gas processing capabilities from Costain Engineering Limited and the experience of BNFL combined in this project to provide the necessary problem-solving skills necessary for this waste storage upgrading and extension project. A retrofitted inerting facility was fitted to an existing building and a new storage extension was fitted, both without interrupting reprocessing operations at Sellafield. (UK)

  10. Computability, complexity, logic

    CERN Document Server

    Börger, Egon

    1989-01-01

    The theme of this book is formed by a pair of concepts: the concept of formal language as carrier of the precise expression of meaning, facts and problems, and the concept of algorithm or calculus, i.e. a formally operating procedure for the solution of precisely described questions and problems. The book is a unified introduction to the modern theory of these concepts, to the way in which they developed first in mathematical logic and computability theory and later in automata theory, and to the theory of formal languages and complexity theory. Apart from considering the fundamental themes an

  11. Complex adaptive systems ecology

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2003-01-01

    In the following, I will analyze two articles called Complex Adaptive Systems EcologyI & II (Molin & Molin, 1997 & 2000). The CASE-articles are some of the more quirkyarticles that have come out of the Molecular Microbial Ecology Group - a groupwhere I am currently making observational studies....... They are the result of acooperation between Søren Molin, professor in the group, and his brother, JanMolin, professor at Department of Organization and Industrial Sociology atCopenhagen Business School. The cooperation arises from the recognition that bothmicrobial ecology and sociology/organization theory works...

  12. Complexity in Managing Modularization

    DEFF Research Database (Denmark)

    Hansen, Poul H. Kyvsgård; Sun, Hongyi

    2011-01-01

    In general, the phenomenon of managing modularization is not well known. The cause-effect relationships between modularization and realized benefits are complex and comprehensive. Though a number of research works have contributed to the study of the phenomenon of efficient and effective...... modularization management it is far from clarified. Recognizing the need for further empirical research, we have studied 40 modularity cases in various companies. The studies have been designed as long-term studies leaving time for various types of modularization benefits to emerge. Based on these studies we...... have developed a framework to support the heuristic and iterative process of planning and realizing modularization benefits....

  13. Procuring complex performance

    DEFF Research Database (Denmark)

    Hartmann, A.; Roehrich, J.; Frederiksen, Lars

    2014-01-01

    the transition process. Design/methodology/approach – A multiple, longitudinal case study method is used to examine the transition towards PCP. The study deploys rich qualitative data sets by combining semi-structured interviews, focus group meetings and organisational reports and documents. Findings...... and relational challenges they need to master when facing higher levels of performance and infrastructural complexity. Originality/value – The study adds to the limited empirical and conceptual understanding on the nature of long-term public-private interactions in PCP. It contributes through a rare focus...

  14. Complex photonic structures

    International Nuclear Information System (INIS)

    Wiersma, D.S.

    2013-01-01

    We discuss in detail the optical properties of complex photonic structures, in particular those with a dominating disorder component. We will focus on their general transport properties, as well as on their use as light sources (random lasers). The basis for the theory of multiple light scattering in random systems will be explained as a tutorial introduction to the topic, including the explicit calculation of the effect of coherent backscattering. We will discuss various structures that go beyond regular disordered ones, in particular Levy glasses, liquid crystals, and quasicrystals, and show examples of their optical properties both from a conceptual and practical point of view.

  15. Fluorido complexes of technetium

    Energy Technology Data Exchange (ETDEWEB)

    Mariappan Balasekaran, Samundeeswari

    2013-07-04

    Fluorine chemistry has received considerable interest during recent years due to its significant role in the life sciences, especially for drug development. Despite the great nuclear medicinal importance of the radioactive metal technetium in radiopharmaceuticals, its coordination chemistry with the fluorido ligand is by far less explored than that of other ligands. Up to now, only a few technetium fluorides are known. This thesis contains the synthesis, spectroscopic and structural characterization of novel technetium fluorides in the oxidation states ''+1'', ''+2'', ''+4'' and ''+6''. In the oxidation state ''+6'', the fluoridotechnetates were synthesized either from nitridotechnetic(VI) acid or from pertechnetate by using reducing agent and have been isolated as cesium or tetraethylammonium salts. The compounds were characterized spectroscopically and structurally. In the intermediate oxidation state ''+4'', hexafluoridotechnetate(IV) was known for long time and studied spectroscopically. This thesis reports novel and improved syntheses and solved the critical issues of early publications such as the color, some spectroscopic properties and the structure of this key compound. Single crystal analyses of alkali metal, ammonium and tetramethylammonium salts of hexafluoridotechnetate(IV) are presented. In aqueous alkaline solutions, the ammonium salt of hexafluoridotechnetate(IV) undergoes hydrolysis and forms an oxido-bridged dimeric complex. It is the first step hydrolysis product of hexafluoridotechnetate(IV) and was characterized by spectroscopic and crystallographic methods. Low-valent technetium fluorides with the metal in the oxidation states of ''+2'' or ''+1'' are almost unknown. A detailed description of the synthesis and characterization of pentafluoridonitrosyltechnetate(II) is presented. The

  16. Complex Strategic Choices

    DEFF Research Database (Denmark)

    Leleur, Steen

    to strategic decision making, Complex Strategic Choices presents a methodology which is further illustrated by a number of case studies and example applications. Dr. Techn. Steen Leleur has adapted previously established research based on feedback and input from various conferences, journals and students...... resulting in new material stemming from and focusing on practical application of a systemic approach. The outcome is a coherent and flexible approach named systemic planning. The inclusion of both the theoretical and practical aspects of systemic planning makes this book a key resource for researchers...

  17. Dismounted Complex Blast Injury.

    Science.gov (United States)

    Andersen, Romney C; Fleming, Mark; Forsberg, Jonathan A; Gordon, Wade T; Nanos, George P; Charlton, Michael T; Ficke, James R

    2012-01-01

    The severe Dismounted Complex Blast Injury (DCBI) is characterized by high-energy injuries to the bilateral lower extremities (usually proximal transfemoral amputations) and/or upper extremity (usually involving the non-dominant side), in addition to open pelvic injuries, genitourinary, and abdominal trauma. Initial resuscitation and multidisciplinary surgical management appear to be the keys to survival. Definitive treatment follows general principals of open wound management and includes decontamination through aggressive and frequent debridement, hemorrhage control, viable tissue preservation, and appropriate timing of wound closure. These devastating injuries are associated with paradoxically favorable survival rates, but associated injuries and higher amputation levels lead to more difficult reconstructive challenges.

  18. The Frankenstein Complex

    DEFF Research Database (Denmark)

    Jensen, Boris Brorman

    2016-01-01

    In his polemic essay Boris Brorman Jensen raises the issue of a perceived academic reluctance to acknowledge the impact of real-world pragmatics on the architectural expression of built architecture. “One might claim that parts of architectural academia suffer from a Frankenstein complex that seems...... to feed a certain academic fear of dealing with the messiness of the real world. This professional fear that the political, social, technical, economic and legal realities will fundamentally weaken and compromise pure architectural thinking rests on the misperception that architecture is not, essentially...

  19. Complex performance in construction

    DEFF Research Database (Denmark)

    Bougrain, Frédéric; Forman, Marianne; Gottlieb, Stefan Christoffer

    To fulfil the expectations of demanding clients, new project-delivery mechanisms have been developed. Approaches focusing on performance-based building or new procurement processers such as new forms of private-public partnerships are considered as solutions improving the overall performance...... to the end users. This report summarises the results from work undertaken in the international collaborative project “Procuring and Operating Complex Products and Systems in Construction” (POCOPSC). POCOPSC was carried out in the period 2010-2014. The project was executed in collaboration between CSTB...

  20. Herding Complex Networks

    KAUST Repository

    Ruf, Sebastian F.

    2018-04-12

    The problem of controlling complex networks is of interest to disciplines ranging from biology to swarm robotics. However, controllability can be too strict a condition, failing to capture a range of desirable behaviors. Herdability, which describes the ability to drive a system to a specific set in the state space, was recently introduced as an alternative network control notion. This paper considers the application of herdability to the study of complex networks. The herdability of a class of networked systems is investigated and two problems related to ensuring system herdability are explored. The first is the input addition problem, which investigates which nodes in a network should receive inputs to ensure that the system is herdable. The second is a related problem of selecting the best single node from which to herd the network, in the case that a single node is guaranteed to make the system is herdable. In order to select the best herding node, a novel control energy based herdability centrality measure is introduced.

  1. Complexity in language acquisition.

    Science.gov (United States)

    Clark, Alexander; Lappin, Shalom

    2013-01-01

    Learning theory has frequently been applied to language acquisition, but discussion has largely focused on information theoretic problems-in particular on the absence of direct negative evidence. Such arguments typically neglect the probabilistic nature of cognition and learning in general. We argue first that these arguments, and analyses based on them, suffer from a major flaw: they systematically conflate the hypothesis class and the learnable concept class. As a result, they do not allow one to draw significant conclusions about the learner. Second, we claim that the real problem for language learning is the computational complexity of constructing a hypothesis from input data. Studying this problem allows for a more direct approach to the object of study--the language acquisition device-rather than the learnable class of languages, which is epiphenomenal and possibly hard to characterize. The learnability results informed by complexity studies are much more insightful. They strongly suggest that target grammars need to be objective, in the sense that the primitive elements of these grammars are based on objectively definable properties of the language itself. These considerations support the view that language acquisition proceeds primarily through data-driven learning of some form. Copyright © 2013 Cognitive Science Society, Inc.

  2. Dynamics in Complex Coacervates

    Science.gov (United States)

    Perry, Sarah

    Understanding the dynamics of a material provides detailed information about the self-assembly, structure, and intermolecular interactions present in a material. While rheological methods have long been used for the characterization of complex coacervate-based materials, it remains a challenge to predict the dynamics for a new system of materials. Furthermore, most work reports only qualitative trends exist as to how parameters such as charge stoichiometry, ionic strength, and polymer chain length impact self-assembly and material dynamics, and there is little information on the effects of polymer architecture or the organization of charges within a polymer. We seek to link thermodynamic studies of coacervation phase behavior with material dynamics through a carefully-controlled, systematic study of coacervate linear viscoelasticity for different polymer chemistries. We couple various methods of characterizing the dynamics of polymer-based complex coacervates, including the time-salt superposition methods developed first by Spruijt and coworkers to establish a more mechanistic strategy for comparing the material dynamics and linear viscoelasticity of different systems. Acknowledgment is made to the Donors of the American Chemical Society Petroleum Research Fund for support of this research.

  3. River rating complexity

    Science.gov (United States)

    Holmes, Robert R.

    2016-01-01

    Accuracy of streamflow data depends on the veracity of the rating model used to derive a continuous time series of discharge from the surrogate variables that can readily be collected autonomously at a streamgage. Ratings are typically represented as a simple monotonic increasing function (simple rating), meaning the discharge is a function of stage alone, however this is never truly the case unless the flow is completely uniform at all stages and in transitions from one stage to the next. For example, at some streamflow-monitoring sites the discharge on the rising limb of the hydrograph is discernably larger than the discharge at the same stage on the falling limb of the hydrograph. This is the so-called “loop rating curve” (loop rating). In many cases, these loops are quite small and variation between rising- and falling-limb discharge measurements made at the same stage are well within the accuracy of the measurements. However, certain hydraulic conditions can produce a loop that is large enough to preclude use of a monotonic rating. A detailed data campaign for the Mississippi River at St. Louis, Missouri during a multi-peaked flood over a 56-day period in 2015 demonstrates the rating complexity at this location. The shifting-control method used to deal with complexity at this site matched all measurements within 8%.

  4. Shapes of interacting RNA complexes

    DEFF Research Database (Denmark)

    Fu, Benjamin Mingming; Reidys, Christian

    2014-01-01

    Shapes of interacting RNA complexes are studied using a filtration via their topological genus. A shape of an RNA complex is obtained by (iteratively) collapsing stacks and eliminating hairpin loops.This shape-projection preserves the topological core of the RNA complex and for fixed topological...... genus there are only finitely many such shapes. Our main result is a new bijection that relates the shapes of RNA complexes with shapes of RNA structures. This allows to compute the shape polynomial of RNA complexes via the shape polynomial of RNA structures. We furthermore present a linear time uniform...... sampling algorithm for shapes of RNA complexes of fixed topological genus....

  5. Complexation reactions in pyridine and 2,6-dimethylpyridine-water system: The quantum-chemical description and the path to liquid phase separation

    Science.gov (United States)

    Chernia, Zelig; Tsori, Yoav

    2018-03-01

    Phase separation in substituted pyridines in water is usually described as an interplay between temperature-driven breakage of hydrogen bonds and the associating interaction of the van der Waals force. In previous quantum-chemical studies, the strength of hydrogen bonding between one water and one pyridine molecules (the 1:1 complex) was assigned a pivotal role. It was accepted that the disassembly of the 1:1 complex at a critical temperature leads to phase separation and formation of the miscibility gap. Yet, for over two decades, notable empirical data and theoretical arguments were presented against that view, thus revealing the need in a revised quantum-mechanical description. In the present study, pyridine-water and 2,6-dimethylpyridine-water systems at different complexation stages are calculated using high level Kohn-Sham theory. The hydrophobic-hydrophilic properties are accounted for by the polarizable continuum solvation model. Inclusion of solvation in free energy of formation calculations reveals that 1:1 complexes are abundant in the organically rich solvents but higher level oligomers (i.e., 2:1 dimers with two pyridines and one water molecule) are the only feasible stable products in the more polar media. At the critical temperature, the dissolution of the external hydrogen bonds between the 2:1 dimer and the surrounding water molecules induces the demixing process. The 1:1 complex acts as a precursor in the formation of the dimers but is not directly involved in the demixing mechanism. The existence of the miscibility gap in one pyridine-water system and the lack of it in another is explained by the ability of the former to maintain stable dimerization. Free energy of formation of several reaction paths producing the 2:1 dimers is calculated and critically analyzed.

  6. Complex dynamical invariants for two-dimensional complex potentials

    Indian Academy of Sciences (India)

    Abstract. Complex dynamical invariants are searched out for two-dimensional complex poten- tials using rationalization method within the framework of an extended complex phase space characterized by x = x1 + ip3, y = x2 + ip4, px = p1 + ix3, py = p2 + ix4. It is found that the cubic oscillator and shifted harmonic oscillator ...

  7. OF AGROINDUSTRIAL COMPLEX MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Ruslan E. Mansurov

    2017-06-01

    Full Text Available The relevance of this work is determined, on the one hand, by tightening of the foreign political situation and its possible negative impact on the food security of the country, and, on the other hand, by the crisis of the domestic agricultural sector. These factors demand the development of new approaches to regional agroindustrial complex (AIC management. The aim is to develop a methodology for assessing the level of food self-sufficiency in main food areas of the Volgograd region. The author used the results of the statistical materials of AIC of the Volgograd region for 2016. The analytical methods included mathematical analysis and comparison. The main results are as follows. Based on the analysis of the current situation to ensure food security of Russia it was proved that at the present time it is necessary to develop effective indicators showing the level of self-sufficiency in basic food regions. It was also revealed that at the moment this indicator in the system of regional agrarian and industrial complex is not controlled. As a result of generalization of existing approaches the author’s method of rating the level of self-sufficiency of regions was offered. Its testing was carried out in several districts of the Volgograd region. The proposed authoring method of rating estimation of self-sufficiency in basic foodstuffs can be used in the regional agroindustrial complex management system at the federal and local levels. It can be used to rank areas in terms of their self-sufficiency in basic foodstuffs. This allows us to focus on the development of backward areas of agro-food and make appropriate management decisions. The final rating value - 0.759 obtained by the results of analysis of the situation in the Volgograd region means that the situation in matters of selfsufficiency in basic foodstuffs in general is good. However, we should aim at the maximum possible value of the rating - 1. In the application of the proposed

  8. Thermodynamics of complexity

    DEFF Research Database (Denmark)

    Westerhoff, Hans V.; Jensen, Peter Ruhdal; Snoep, Jacky L.

    1998-01-01

    -called emergent properties. Tendency towards increased entropy is an essential determinant for the behaviour of ideal gas mixtures, showing that even in the simplest physical/chemical systems, (dys)organisation of components is crucial for the behaviour of systems. This presentation aims at illustrating...... that the behaviour of two functionally interacting biological components (molecules, protein domains, pathways, organelles) differs from the behaviour these components would exhibit in isolation from one another, where the difference should be essential for the maintenance and growth of the living state, For a true...... understanding of this BioComplexity, modem thermodynamic concepts and methods (nonequilibrium thermodynamics, metabolic and hierarchical control analysis) will be needed. We shall propose to redefine nonequilibrium thermodynamics as: The science that aims at understanding the behaviour of nonequilibrium systems...

  9. Complexity, Metastability and Nonextensivity

    Science.gov (United States)

    Beck, C.; Benedek, G.; Rapisarda, A.; Tsallis, C.

    Work and heat fluctuations in systems with deterministic and stochastic forces / E. G. D. Cohen and R. Van Zon -- Is the entropy S[symbol] extensive or nonextensive? / C. Tsallis -- Superstatistics: recent developments and applications / C. Beck -- Two stories outside Boltzmann-Gibbs statistics: Mori's Q-phase transitions and glassy dynamics at the onset of chaos / A. Robledo, F. Baldovin and E. Mayoral -- Time-averages and the heat theorem / A. Carati -- Fundamental formulae and numerical evidences for the central limit theorem in Tsallis statistics / H. Suyari -- Generalizing the Planck distribution / A. M. C. Soma and C. Tsallis -- The physical roots of complexity: renewal or modulation? / P. Grigolini -- Nonequivalent ensembles and metastability / H. Touchette and R. S. Ellis -- Statistical physics for cosmic structures / L. Pietronero and F. Sylos Labini -- Metastability and anomalous behavior in the HMF model: connections to nonextensive thermodynamics and glassy dynamics / A. Pluchino, A. Rapisarda and V. Latora -- Vlasov analysis of relaxation and meta-equilibrium / C. Anteneodo and R. O. Vallejos -- Weak chaos in large conservative systems - infinite-range coupled standard maps / L. G. Moyano, A. P. Majtey and C. Tsallis -- Deterministc aging / E. Barkai -- Edge of chaos of the classical kicked top map: sensitivity to initial conditions / S. M. Duarte Queirós and C. Tsallis -- What entropy at the edge of chaos? / M. Lissia, M. Coraddu and R. Tonelli -- Fractal growth of carbon schwarzites / G. Benedek ... [et al.] -- Clustering and interface propagation in interacting particle dynamics / A. Provata and V. K. Noussiou -- Resonant activation and noise enhanced stability in Josephson junctions / A. L. Pankratov and B. Spagnolo -- Symmetry breaking induced directed motions / C.-H. Chang and T. Y. Tsong -- General theory of Galilean-invariant entropic lattic Boltzmann models / B. M. Boghosian -- Unifying approach to the jamming transition in granular media and

  10. Complex algebraic geometry

    CERN Document Server

    Kollár, János

    1997-01-01

    This volume contains the lectures presented at the third Regional Geometry Institute at Park City in 1993. The lectures provide an introduction to the subject, complex algebraic geometry, making the book suitable as a text for second- and third-year graduate students. The book deals with topics in algebraic geometry where one can reach the level of current research while starting with the basics. Topics covered include the theory of surfaces from the viewpoint of recent higher-dimensional developments, providing an excellent introduction to more advanced topics such as the minimal model program. Also included is an introduction to Hodge theory and intersection homology based on the simple topological ideas of Lefschetz and an overview of the recent interactions between algebraic geometry and theoretical physics, which involve mirror symmetry and string theory.

  11. Mutagenicity of complex mixtures

    International Nuclear Information System (INIS)

    Pelroy, R.A.

    1985-01-01

    The effect of coal-derived complex chemical mixtures on the mutagenicity of 6-aminochrysene (6-AC) was determined with Salmonella typhimurium TA98. Previous results suggested that the mutagenic potency of 6-AC for TA98 in the standard microsomal activation (Ames) assay increased if it was presented to the cells mixed with high-boiling coal liquids (CL) from the solvent refined coal (SRC) process. In this year's work, the apparent mutational synergism of CL and 6-AC was independently verified in a fluctuation bioassay which allowed quantitation of mutational frequencies and cell viability. The results of this assay system were similar to those in the Ames assay. Moreover, the fluctation assay revealed that mutagenesis and cellular toxicity induced by 6-AC were both strongly enhanced if 6-AC was presented to the cells mixed in a high-boiling CL. 4 figures

  12. Complex Algebraic Varieties

    CERN Document Server

    Peternell, Thomas; Schneider, Michael; Schreyer, Frank-Olaf

    1992-01-01

    The Bayreuth meeting on "Complex Algebraic Varieties" focussed on the classification of algebraic varieties and topics such as vector bundles, Hodge theory and hermitian differential geometry. Most of the articles in this volume are closely related to talks given at the conference: all are original, fully refereed research articles. CONTENTS: A. Beauville: Annulation du H(1) pour les fibres en droites plats.- M. Beltrametti, A.J. Sommese, J.A. Wisniewski: Results on varieties with many lines and their applications to adjunction theory.- G. Bohnhorst, H. Spindler: The stability of certain vector bundles on P(n) .- F. Catanese, F. Tovena: Vector bundles, linear systems and extensions of (1).- O. Debarre: Vers uns stratification de l'espace des modules des varietes abeliennes principalement polarisees.- J.P. Demailly: Singular hermitian metrics on positive line bundles.- T. Fujita: On adjoint bundles of ample vector bundles.- Y. Kawamata: Moderate degenerations of algebraic surfaces.- U. Persson: Genus two fibra...

  13. Invitation to complex analysis

    CERN Document Server

    Boas, Ralph P

    2010-01-01

    Ideal for a first course in complex analysis, this book can be used either as a classroom text or for independent study. Written at a level accessible to advanced undergraduates and beginning graduate students, the book is suitable for readers acquainted with advanced calculus or introductory real analysis. The treatment goes beyond the standard material of power series, Cauchy's theorem, residues, conformal mapping, and harmonic functions by including accessible discussions of intriguing topics that are uncommon in a book at this level. The flexibility afforded by the supplementary topics and applications makes the book adaptable either to a short, one-term course or to a comprehensive, full-year course. Detailed solutions of the exercises both serve as models for students and facilitate independent study. Supplementary exercises, not solved in the book, provide an additional teaching tool. This second edition has been painstakingly revised by the author's son, himself an award-winning mathematical expositor...

  14. Genetics of complex diseases

    DEFF Research Database (Denmark)

    Mellerup, Erling; Møller, Gert Lykke; Koefoed, Pernille

    2012-01-01

    A complex disease with an inheritable component is polygenic, meaning that several different changes in DNA are the genetic basis for the disease. Such a disease may also be genetically heterogeneous, meaning that independent changes in DNA, i.e. various genotypes, can be the genetic basis...... for the disease. Each of these genotypes may be characterized by specific combinations of key genetic changes. It is suggested that even if all key changes are found in genes related to the biology of a certain disease, the number of combinations may be so large that the number of different genotypes may be close...... to the number of patients suffering from the disease. This hypothesis is based on a study of bipolar disorder....

  15. A Cryo Complex Control

    CERN Document Server

    Alferov, V; Fedorchenko, V; Ivanova, N; Kholkin, A; Klimov, S; Krendelev, V; Kuznetsov, S; Lukyantsev, A; Lutchev, A; Milutkin, V; Sytin, A N; Vasilev, D

    2004-01-01

    A Cryogenic complex is being constructed to provide by liquid helium and nitrogen the RF-separator of kaons. About 500 parameters including temperature (1,8…300)K, liquid helium/nitrogen level, vacuum, 300 digital signals have to be measured, 70 commands generated, 20 closed loops activated. The paper describes controls electronics which includes home made I8051 compatible controllers connected by the CAN field bus to a bus controller and interface electronic modules for: - temperature measurements; - liquid Ni and He level measurements; - vacuum pumps current measurements; - analog and digital signals measurements and generations. The modules are tested together with signal imitators within a vertical slice of the Control System based on EPICS tools.

  16. Segmentation of complex document

    Directory of Open Access Journals (Sweden)

    Souad Oudjemia

    2014-06-01

    Full Text Available In this paper we present a method for segmentation of documents image with complex structure. This technique based on GLCM (Grey Level Co-occurrence Matrix used to segment this type of document in three regions namely, 'graphics', 'background' and 'text'. Very briefly, this method is to divide the document image, in block size chosen after a series of tests and then applying the co-occurrence matrix to each block in order to extract five textural parameters which are energy, entropy, the sum entropy, difference entropy and standard deviation. These parameters are then used to classify the image into three regions using the k-means algorithm; the last step of segmentation is obtained by grouping connected pixels. Two performance measurements are performed for both graphics and text zones; we have obtained a classification rate of 98.3% and a Misclassification rate of 1.79%.

  17. Complexity in Evolutionary Processes

    International Nuclear Information System (INIS)

    Schuster, P.

    2010-01-01

    Darwin's principle of evolution by natural selection is readily casted into a mathematical formalism. Molecular biology revealed the mechanism of mutation and provides the basis for a kinetic theory of evolution that models correct reproduction and mutation as parallel chemical reaction channels. A result of the kinetic theory is the existence of a phase transition in evolution occurring at a critical mutation rate, which represents a localization threshold for the population in sequence space. Occurrence and nature of such phase transitions depend critically on fitness landscapes. The fitness landscape being tantamount to a mapping from sequence or genotype space into phenotype space is identified as the true source of complexity in evolution. Modeling evolution as a stochastic process is discussed and neutrality with respect to selection is shown to provide a major challenge for understanding evolutionary processes (author)

  18. Complex Interfaces Under Change

    DEFF Research Database (Denmark)

    Rosbjerg, Dan

    The hydrosphere is dynamic across the major compartments of the Earth system: the atmosphere, the oceans and seas, the land surface water, and the groundwater within the strata below the two last compartments. The global geography of the hydrosphere essentially depends on thermodynamic and mechan...... these interfaces and interfaced compartments and processes. Climate, sea-level, oceanographic currents and hydrological processes are all affected, while anthropogenic changes are often intense in the geographic settings corresponding to such interfaces....... and mechanical processes that develop within this structure. Water-related processes at the interfaces between the compartments are complex, depending both on the interface itself, and on the characteristics of the interfaced compartments. Various aspects of global change directly or indirectly impact...

  19. Iridium complexes for electrocatalysis

    Science.gov (United States)

    Sheehan, Stafford Wheeler; Hintermair, Ulrich; Thomsen, Julianne M; Brudvig, Gary W; Crabtree, Robert H

    2017-10-17

    Solution-phase (e.g., homogeneous) or surface-immobilized (e.g., heterogeneous) electrode-driven oxidation catalysts based on iridium coordination compounds which self-assemble upon chemical or electrochemical oxidation of suitable precursors and methods of making and using thereof are. Iridium species such as {[Ir(LX).sub.x(H.sub.2O).sub.y(.mu.-O)].sub.z.sup.m+}.sub.n wherein x, y, m are integers from 0-4, z and n from 1-4 and LX is an oxidation-resistant chelate ligand or ligands, such as such as 2(2-pyridyl)-2-propanolate, form upon oxidation of various molecular iridium complexes, for instance [Cp*Ir(LX)OH] or [(cod)Ir(LX)] (Cp*=pentamethylcyclopentadienyl, cod=cis-cis,1,5-cyclooctadiene) when exposed to oxidative conditions, such as sodium periodate (NaIO.sub.4) in aqueous solution at ambient conditions.

  20. Complex Hamiltonian Dynamics

    CERN Document Server

    Bountis, Tassos

    2012-01-01

    This book introduces and explores modern developments in the well established field of Hamiltonian dynamical systems. It focuses on high degree-of-freedom systems and the transitional regimes between regular and chaotic motion. The role of nonlinear normal modes is highlighted and the importance of low-dimensional tori in the resolution of the famous FPU paradox is emphasized. Novel powerful numerical methods are used to study localization phenomena and distinguish order from strongly and weakly chaotic regimes. The emerging hierarchy of complex structures in such regimes gives rise to particularly long-lived patterns and phenomena called quasi-stationary states, which are explored in particular in the concrete setting of one-dimensional Hamiltonian lattices and physical applications in condensed matter systems.  The self-contained and pedagogical approach is blended with a unique balance between mathematical rigor, physics insights and concrete applications. End of chapter exercises and (more demanding) res...

  1. Turbulence in complex terrain

    Energy Technology Data Exchange (ETDEWEB)

    Mann, Jakob [Risoe National Lab., Wind Energy and Atmosheric Physics Dept., Roskilde (Denmark)

    1999-03-01

    The purpose of this work is to develop a model of the spectral velocity-tensor in neutral flow over complex terrain. The resulting equations are implemented in a computer code using the mean flow generated by a linear mean flow model as input. It estimates turbulence structure over hills (except on the lee side if recirculation is present) in the so-called outer layer and also models the changes in turbulence statistics in the vicinity roughness changes. The generated turbulence fields are suitable as input for dynamic load calculations on wind turbines and other tall structures and is under implementation in the collection of programs called WA{sup s}P Engineering. (au) EFP-97; EU-JOULE-3. 15 refs.

  2. Evolution of complex dynamics

    Science.gov (United States)

    Wilds, Roy; Kauffman, Stuart A.; Glass, Leon

    2008-09-01

    We study the evolution of complex dynamics in a model of a genetic regulatory network. The fitness is associated with the topological entropy in a class of piecewise linear equations, and the mutations are associated with changes in the logical structure of the network. We compare hill climbing evolution, in which only mutations that increase the fitness are allowed, with neutral evolution, in which mutations that leave the fitness unchanged are allowed. The simple structure of the fitness landscape enables us to estimate analytically the rates of hill climbing and neutral evolution. In this model, allowing neutral mutations accelerates the rate of evolutionary advancement for low mutation frequencies. These results are applicable to evolution in natural and technological systems.

  3. Early AIDS dementia complex

    International Nuclear Information System (INIS)

    Mountz, J.M.; Speed, N.M.; Adams, K.; Schwartz, J.A.; Gross, M.D.; Ostrow, D.G.

    1988-01-01

    A frequent complication of the acquired immunodeficiency syndrome (AIDS) is AIDS dementia complex (ADC). The authors evaluated seven patients with AIDS (aged 28-55 years, all male) for ADC by psychiatric evaluation, neuropsychological testing, CT scanning, and IMP-SPECT. Six of seven patients exhibited cognitive or behavioral abnormalities. Neuropsychological testing showed general deficits but no cases of explicit dementia. SPECT showed marked abnormalities in two cases: posterior temporal-parietal diminution of tracer uptake in one case (posterior/anterior=0.81) and marked right/left subcortical asymmetry (1.17) in the other. In three additional cases there was asymmetric tracer uptake in the subcortical and parietal regions. CT findings were normal in all seven cases. The authors conclude that functional imaging with the use of IMP-SPECT may be a useful method to follow ADC progression and response to therapy

  4. Measurement of complex surfaces

    International Nuclear Information System (INIS)

    Brown, G.M.

    1993-05-01

    Several of the components used in coil fabrication involve complex surfaces and dimensions that are not well suited to measurements using conventional dimensional measuring equipment. Some relatively simple techniques that are in use in the SSCL Magnet Systems Division (MSD) for incoming inspection will be described, with discussion of their suitability for specific applications. Components that are submitted for MSD Quality Assurance (QA) dimensional inspection may be divided into two distinct categories; the first category involves components for which there is an approved drawing and for which all nominal dimensions are known; the second category involves parts for which 'reverse engineering' is required, the part is available but there are no available drawings or dimensions. This second category typically occurs during development of coil end parts and coil turn filler parts where it is necessary to manually shape the part and then measure it to develop the information required to prepare a drawing for the part

  5. Complexity Science for Simpletons

    Directory of Open Access Journals (Sweden)

    Feinstein C. A.

    2006-07-01

    Full Text Available In this article, we shall describe some of the most interesting topics in the subject of Complexity Science for a general audience. Anyone with a solid foundation in high school mathematics (with some calculus and an elementary understanding of computer programming will be able to follow this article. First, we shall explain the significance of the P versus NP problem and solve it. Next, we shall describe two other famous mathematics problems, the Collatz 3n+ 1 Conjecture and the Riemann Hypothesis, and show how both Chaitin’s incompleteness theorem and Wolfram’s notion of “computational irreducibility” are important for understanding why no one has, as of yet, solved these two problems.

  6. The Complex Cepstrum - Revisited

    Science.gov (United States)

    Kemerait, R. C., Sr.

    2016-12-01

    Since this paper comes at the twilight of my career, it is appropriate to share my views on a subject very dear to my heart and to my long career. In 2004 "From Frequency to Quefrency: A History of the Cepstrum" was published in the IEEE Signal Processing magazine. There is no question that the authors, Alan V. Oppenheim and Ronald W. Schafer, were pioneers in this area of research, and this publication documents their involvement quite nicely. In parallel research also performed in the 1960's, Childers, et. al., renamed the original "Cepstrum" to the "Power Cepstrum" to avoid confusion with the principal topic of their research, that being the "Complex Cepstrum." The term "Power Cepstrum" has become widely used in the literature since that time. The Childers team, including Dr. Kemerait, published a summary of their work, as of that date, in the IEEE Proceedings of October 1977, and titled the article "The Cepstrum: A Guide to Processing." In the subsequent 40 years, Dr. Kemerait has continued to research cepstral techniques applied to many diverse problems; however, his primary research has been on estimating the depth of underground and underwater events. He has also applied these techniques to biomedical data: EEG, EKG, and Visua-evoked responses as well as on hydroacoustic data ; thereby, determining the "bubble pulse frequency", and the depths of the explosion and the ocean depth at the explosion point. He has also used cepstral techniques in the processing of ground penetrating radar, speech, machine diagnostics, and, throughout these years, seismic data. This paper emphasizes his recent improvements in processing primarily seismic and infrasound data associated with nuclear treaty monitoring. The emphasis is mainly on the recent improvements and the automation of the Complex Cepstrum process.

  7. Complex wounds Feridas complexas

    Directory of Open Access Journals (Sweden)

    Marcus Castro Ferreira

    2006-01-01

    Full Text Available Complex wound is the term used more recently to group those well-known difficult wounds, either chronic or acute, that challenge medical and nursing teams. They defy cure using conventional and simple "dressings" therapy and currently have a major socioeconomic impact. The purpose of this review is to bring these wounds to the attention of the health-care community, suggesting that they should be treated by multidisciplinary teams in specialized hospital centers. In most cases, surgical treatment is unavoidable, because the extent of skin and subcutaneous tissue loss requires reconstruction with grafts and flaps. New technologies, such as the negative pressure device, should be introduced. A brief review is provided of the major groups of complex wounds-diabetic wounds, pressure sores, chronic venous ulcers, post-infection soft-tissue gangrenes, and ulcers resulting from vasculitis.Ferida complexa é uma nova definição para identificar aquelas feridas crônicas e algumas agudas já bem conhecidas e que desafiam equipes médicas e de enfermagem. São difíceis de serem resolvidas usando tratamentos convencionais e simples curativos. Têm atualmente grande impacto sócio-econômico. Esta revisão procura atrair atenção da comunidade de profissionais de saúde para estas feridas, sugerindo que devam ser tratadas por equipe multidisciplinar em centro hospitalar especializado. Na maioria dos casos o tratamento cirúrgico deve ser indicado, uma vez que a perda de pele e tecido subcutâneo é extensa, necessitando de reconstrução com enxertos e retalhos. Nova tecnologia, como uso da terapia por pressão negativa foi introduzido. Breves comentários sobre os principais grupos de feridas complexas: pé diabético, úlceras por pressão, úlceras venosas, síndrome de Fournier e vasculites.

  8. Complex sleep apnea syndrome

    Directory of Open Access Journals (Sweden)

    Wang J

    2013-07-01

    Full Text Available Juan Wang,1,* Yan Wang,1,* Jing Feng,1,2 Bao-yuan Chen,1 Jie Cao1 1Respiratory Department of Tianjin Medical University General Hospital, Tianjin, People's Republic of China; 2Division of Pulmonary and Critical Care Medicine, Duke University Medical Center, Durham, NC, USA *The first two authors contributed equally to this work Abstract: Complex sleep apnea syndrome (CompSAS is a distinct form of sleep-disordered breathing characterized as central sleep apnea (CSA, and presents in obstructive sleep apnea (OSA patients during initial treatment with a continuous positive airway pressure (CPAP device. The mechanisms of why CompSAS occurs are not well understood, though we have a high loop gain theory that may help to explain it. It is still controversial regarding the prevalence and the clinical significance of CompSAS. Patients with CompSAS have clinical features similar to OSA, but they do exhibit breathing patterns like CSA. In most CompSAS cases, CSA events during initial CPAP titration are transient and they may disappear after continued CPAP use for 4–8 weeks or even longer. However, the poor initial experience of CompSAS patients with CPAP may not be avoided, and nonadherence with continued therapy may often result. Treatment options like adaptive servo-ventilation are available now that may rapidly resolve the disorder and relieve the symptoms of this disease with the potential of increasing early adherence to therapy. But these approaches are associated with more expensive and complicated devices. In this review, the definition, potential plausible mechanisms, clinical characteristics, and treatment approaches of CompSAS will be summarized. Keywords: complex sleep apnea syndrome, obstructive sleep apnea, central sleep apnea, apnea threshold, continuous positive airway pressure, adaptive servo-ventilation

  9. Amphotericin B Lipid Complex Injection

    Science.gov (United States)

    Amphotericin B lipid complex injection is used to treat serious, possibly life-threatening fungal infections in people who did ... respond or are unable to tolerate conventional amphotericin B therapy. Amphotericin B lipid complex injection is in ...

  10. [Tissue-specific nucleoprotein complexes].

    Science.gov (United States)

    Riadnova, I Iu; Shataeva, L K; Khavinson, V Kh

    2000-01-01

    A method of isolation of native nucleorprotein complexes from cattle cerebral cortex, thymus, and liver was developed. Compositions of these complexes were studied by means of gel-chromatography and ion-exchange chromatography. These preparations were shown to consist of several fractions of proteins and their complexes differ by molecular mass and electro-chemical properties. Native nucleoprotein complexes revealed high tissue specific activity, which was not species-specific.

  11. Cooperativity of complex salt bridges

    OpenAIRE

    Gvritishvili, Anzor G.; Gribenko, Alexey V.; Makhatadze, George I.

    2008-01-01

    The energetic contribution of complex salt bridges, in which one charged residue (anchor residue) forms salt bridges with two or more residues simultaneously, has been suggested to have importance for protein stability. Detailed analysis of the net energetics of complex salt bridge formation using double- and triple-mutant cycle analysis revealed conflicting results. In two cases, it was shown that complex salt bridge formation is cooperative, i.e., the net strength of the complex salt bridge...

  12. Uranium nucleophilic carbene complexes

    International Nuclear Information System (INIS)

    Tourneux, Jean-Christophe

    2012-01-01

    The only stable f-metal carbene complexes (excluding NHC) metals f present R 2 C 2- groups having one or two phosphorus atoms in the central carbon in alpha position. The objective of this work was to develop the chemistry of carbenes for uranium (metal 5f) with the di-anion C{Ph 2 P(=S)} 2 2- (SCS 2- ) to extend the organometallic chemistry of this element in its various oxidation states (+3-+6), and to reveal the influence of the 5f orbitals on the nature and reactivity of the double bond C=U. We first isolated the reactants M(SCHS) (M = Li and K) and demonstrated the role of the cation M + on the evolution of the di-anion M 2 SCS (M = Li, K, Tl) which is transformed into LiSCHS in THF or into product of intramolecular cyclization K 2 [C(PhPS) 2 (C 6 H 4 )]. We have developed the necessary conditions mono-, bis- and tris-carbene directly from the di-anion SCS 2- and UCl 4 , as the precursor used in uranium chemistry. The protonolysis reactions of amides compounds (U-NEt 2 ) by the neutral ligand SCH 2 S were also studied. The compounds [Li(THF)] 2 [U(SCS)Cl 3 ] and [U(SCS)Cl 2 (THF) 2 ] were then used to prepare a variety of cyclopentadienyl and mono-cyclo-octa-tetra-enyliques uranium(IV) carbene compounds of the DFT analysis of compounds [M(SCS)Cl 2 (py) 2 ] and [M(Cp) 2 (SCS)] (M = U, Zr) reveals the strong polarization of the M=C double bond, provides information on the nature of the σ and π interactions in this binding, and shows the important role of f orbitals. The influence of ancillary ligands on the M=C bond is revealed by examining the effects of replacing Cl - ligands and pyridine by C 5 H 5 - groups. Mulliken and NBO analyzes show that U=C bond, unlike the Zr=C bond, is not affected by the change in environment of the metal center. While the oxidation tests of carbene complexes of U(IV) were disappointing, the first carbene complex of uranium (VI), [UO 2 (SCS)(THF) 2 ], was isolated with the uranyl ion UO 2 2+ . The reactions of compounds UO 2 X 2

  13. Low energy costs of F1Fo ATP synthase reversal in colon carcinoma cells deficient in mitochondrial complex IV.

    Science.gov (United States)

    Zhdanov, Alexander V; Andreev, Dmitry E; Baranov, Pavel V; Papkovsky, Dmitri B

    2017-05-01

    Mitochondrial polarisation is paramount for a variety of cellular functions. Under ischemia, mitochondrial membrane potential (ΔΨm) and proton gradient (ΔpH) are maintained via a reversal of mitochondrial F1Fo ATP synthase (mATPase), which can rapidly deplete ATP and drive cells into energy crisis. We found that under normal conditions in cells with disassembled cytochrome c oxidase complex (COX-deficient HCT116), mATPase maintains ΔΨm at levels only 15-20% lower than in WT cells, and for this utilises relatively little ATP. For a small energy expenditure, mATPase enables mitochondrial ΔpH, protein import, Ca 2+ turnover, and supports free radical detoxication machinery enlarged to protect the cells from oxidative damage. Whereas in COX-deficient cells the main source of ATP is glycolysis, the ΔΨm is still maintained upon inhibition of the adenine nucleotide translocators with bongkrekic acid and carboxyatractyloside, indicating that the role of ANTs is redundant, and matrix substrate level phosphorylation alone or in cooperation with ATP-Mg/P i carriers can continuously support the mATPase activity. Intriguingly, we found that mitochondrial complex III is active, and it contributes not only to free radical production, but also to ΔΨm maintenance and energy budget of COX-deficient cells. Overall, this study demonstrates that F1Fo ATP synthase can support general mitochondrial and cellular functions, working in extremely efficient 'energy saving' reverse mode and flexibly recruiting free radical detoxication and ATP producing / transporting pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Complex mixtures biostudies

    International Nuclear Information System (INIS)

    Springer, D.L.

    1987-01-01

    The objective of the project is to identify potential adverse biological activities associated with human exposures to complex organic mixtures (COM) from energy-related industries. Studies to identify the influence of chemical class fractions from a COM on the initiating activity of a known carcinogen, benzo(a)pyrene (BaP), demonstrated that the polycyclic aromatic hydrocarbons (PAH) and nitrogen-containing polycyclic aromatic compound (NPAC) fractions were the most effective inhibitors of initiation. In an effort to determine the contribution of BaP to the initiating activity of the COM, binding of radiolabeled BaP to mouse skin DNA was measured. Results indicated that binding of BaP to DNA decreased in the presence of the COM so that at initiating COM doses, BaP binding was near the limit detection. Addition of unlabeled BaP to the COM at an amount similar to that originally present in the COM did not significantly increase the binding. Studies to determine the rates of disappearance of carcinogenic PAH from the site of application on the skin indicated that half-lives for PAH differed by a factor of about 2. Analytical methods developed to identify PAH from COM which covalently bind to DNA demonstrated that the lower level of detection is approximately 200 picograms. Developmental studies demonstrated that both pregnant rats and mice treated dermally with a high-boiling COM developed fetuses with major malformations including cleft palate, small lungs, edema, and sagittal suture hemorrhages. 3 figures, 5 tables

  15. Managing Complex Environmental Risks

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, Mikael [Karlstad Univ. (Sweden). Dept. of Environmental Sciences

    2006-09-15

    Environmental and public health risks are often handled in a process in which experts, and sometimes policy makers, try their best to quantitatively assess, evaluate and manage risks. This approach harmonises with mainstream interpretations of sustainable development, which aim at defining a desirable relationship between human and natural systems, for instance by policies that define limit values of different forms of disturbances. However, under conditions of high scientific incertitude, diverging values and distrust, this approach is far from satisfactory. The use of cell phones, hazardous chemicals, nuclear or fossil energy systems, and modern biotechnology are examples of activities causing such risks with high complexity. Against this background, a complementary interpretation of the concept of sustainable development is suggested. This interpretation is operationalised through new formulations of three common principles for public risk management; the precautionary principle, the polluter pays principle and the principle of public participation. Implementation of these reformulated principles would challenge some foundations of present mainstream views on environmental decision-making, but would on the other hand contribute to improved practices for long-term human welfare and planetary survival (full text of contribution)

  16. Managing Complex Environmental Risks

    International Nuclear Information System (INIS)

    Karlsson, Mikael

    2006-01-01

    Environmental and public health risks are often handled in a process in which experts, and sometimes policy makers, try their best to quantitatively assess, evaluate and manage risks. This approach harmonises with mainstream interpretations of sustainable development, which aim at defining a desirable relationship between human and natural systems, for instance by policies that define limit values of different forms of disturbances. However, under conditions of high scientific incertitude, diverging values and distrust, this approach is far from satisfactory. The use of cell phones, hazardous chemicals, nuclear or fossil energy systems, and modern biotechnology are examples of activities causing such risks with high complexity. Against this background, a complementary interpretation of the concept of sustainable development is suggested. This interpretation is operationalised through new formulations of three common principles for public risk management; the precautionary principle, the polluter pays principle and the principle of public participation. Implementation of these reformulated principles would challenge some foundations of present mainstream views on environmental decision-making, but would on the other hand contribute to improved practices for long-term human welfare and planetary survival (full text of contribution)

  17. On Measuring the Complexity of Networks: Kolmogorov Complexity versus Entropy

    Directory of Open Access Journals (Sweden)

    Mikołaj Morzy

    2017-01-01

    Full Text Available One of the most popular methods of estimating the complexity of networks is to measure the entropy of network invariants, such as adjacency matrices or degree sequences. Unfortunately, entropy and all entropy-based information-theoretic measures have several vulnerabilities. These measures neither are independent of a particular representation of the network nor can capture the properties of the generative process, which produces the network. Instead, we advocate the use of the algorithmic entropy as the basis for complexity definition for networks. Algorithmic entropy (also known as Kolmogorov complexity or K-complexity for short evaluates the complexity of the description required for a lossless recreation of the network. This measure is not affected by a particular choice of network features and it does not depend on the method of network representation. We perform experiments on Shannon entropy and K-complexity for gradually evolving networks. The results of these experiments point to K-complexity as the more robust and reliable measure of network complexity. The original contribution of the paper includes the introduction of several new entropy-deceiving networks and the empirical comparison of entropy and K-complexity as fundamental quantities for constructing complexity measures for networks.

  18. Technetium complexation by macrocyclic compounds

    International Nuclear Information System (INIS)

    Li Fan Yu.

    1983-01-01

    Research in nuclear medicine are directed towards the labelling of biological molecules, however, sup(99m)Tc does not show sufficient affinity for these molecules. The aim of this study was to evaluate the ability of macrocyclic compounds to bind strongly technetium in order to be used as complexation intermediate. The reducing agents used were a stannous complex and sodium dithionite. Cryptates and polyesters are not good complexing agents. They form two complexes: a 2:1 sandwich complex or 3:2 and a 1:1 complex. Cyclams are good complexing agents for technetium their complexations strength was determined by competition with pyrophosphate, gluconate and DTPA. Using the method of ligand exchange, the oxidation state of technetium in the Tc-cyclam complex was IV or V. They are 1:1 cationic complexes, the complex charge is +1. The biodistribution in rats of labelling solutions containing (cyclam 14 ane N 4 ) C 12 H 25 shows a good urinary excretion without intoxication risks [fr

  19. Complexity a very short introduction

    CERN Document Server

    Holland, John H

    2014-01-01

    The importance of complexity is well-captured by Hawking's comment: "Complexity is the science of the 21st century". From the movement of flocks of birds to the Internet, environmental sustainability, and market regulation, the study and understanding of complex non-linear systems has become highly influential over the last 30 years. In this Very Short Introduction, one of the leading figures in the field, John Holland, introduces the key elements and conceptual framework of complexity. From complex physical systems such as fluid flow and the difficulties of predicting weather, to complex adaptive systems such as the highly diverse and interdependent ecosystems of rainforests, he combines simple, well-known examples - Adam Smith's pin factory, Darwin's comet orchid, and Simon's 'watchmaker' - with an account of the approaches, involving agents and urn models, taken by complexity theory. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost eve...

  20. Complexity of formation in holography

    International Nuclear Information System (INIS)

    Chapman, Shira; Marrochio, Hugo; Myers, Robert C.

    2017-01-01

    It was recently conjectured that the quantum complexity of a holographic boundary state can be computed by evaluating the gravitational action on a bulk region known as the Wheeler-DeWitt patch. We apply this complexity=action duality to evaluate the ‘complexity of formation’ (DOI: 10.1103/PhysRevLett.116.191301; 10.1103/PhysRevD.93.086006), i.e. the additional complexity arising in preparing the entangled thermofield double state with two copies of the boundary CFT compared to preparing the individual vacuum states of the two copies. We find that for boundary dimensions d>2, the difference in the complexities grows linearly with the thermal entropy at high temperatures. For the special case d=2, the complexity of formation is a fixed constant, independent of the temperature. We compare these results to those found using the complexity=volume duality.

  1. Complexity of formation in holography

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, Shira [Perimeter Institute for Theoretical Physics,Waterloo, ON N2L 2Y5 (Canada); Marrochio, Hugo [Perimeter Institute for Theoretical Physics,Waterloo, ON N2L 2Y5 (Canada); Department of Physics & Astronomy and Guelph-Waterloo Physics Institute,University of Waterloo, Waterloo, ON N2L 3G1 (Canada); Myers, Robert C. [Perimeter Institute for Theoretical Physics,Waterloo, ON N2L 2Y5 (Canada)

    2017-01-16

    It was recently conjectured that the quantum complexity of a holographic boundary state can be computed by evaluating the gravitational action on a bulk region known as the Wheeler-DeWitt patch. We apply this complexity=action duality to evaluate the ‘complexity of formation’ (DOI: 10.1103/PhysRevLett.116.191301; 10.1103/PhysRevD.93.086006), i.e. the additional complexity arising in preparing the entangled thermofield double state with two copies of the boundary CFT compared to preparing the individual vacuum states of the two copies. We find that for boundary dimensions d>2, the difference in the complexities grows linearly with the thermal entropy at high temperatures. For the special case d=2, the complexity of formation is a fixed constant, independent of the temperature. We compare these results to those found using the complexity=volume duality.

  2. Joint molecule resolution requires the redundant activities of MUS-81 and XPF-1 during Caenorhabditis elegans meiosis.

    Directory of Open Access Journals (Sweden)

    Nigel J O'Neil

    Full Text Available The generation and resolution of joint molecule recombination intermediates is required to ensure bipolar chromosome segregation during meiosis. During wild type meiosis in Caenorhabditis elegans, SPO-11-generated double stranded breaks are resolved to generate a single crossover per bivalent and the remaining recombination intermediates are resolved as noncrossovers. We discovered that early recombination intermediates are limited by the C. elegans BLM ortholog, HIM-6, and in the absence of HIM-6 by the structure specific endonuclease MUS-81. In the absence of both MUS-81 and HIM-6, recombination intermediates persist, leading to chromosome breakage at diakinesis and inviable embryos. MUS-81 has an additional role in resolving late recombination intermediates in C. elegans. mus-81 mutants exhibited reduced crossover recombination frequencies suggesting that MUS-81 is required to generate a subset of meiotic crossovers. Similarly, the Mus81-related endonuclease XPF-1 is also required for a subset of meiotic crossovers. Although C. elegans gen-1 mutants have no detectable meiotic defect either alone or in combination with him-6, mus-81 or xpf-1 mutations, mus-81;xpf-1 double mutants are synthetic lethal. While mus-81;xpf-1 double mutants are proficient for the processing of early recombination intermediates, they exhibit defects in the post-pachytene chromosome reorganization and the asymmetric disassembly of the synaptonemal complex, presumably triggered by crossovers or crossover precursors. Consistent with a defect in resolving late recombination intermediates, mus-81; xpf-1 diakinetic bivalents are aberrant with fine DNA bridges visible between two distinct DAPI staining bodies. We were able to suppress the aberrant bivalent phenotype by microinjection of activated human GEN1 protein, which can cleave Holliday junctions, suggesting that the DNA bridges in mus-81; xpf-1 diakinetic oocytes are unresolved Holliday junctions. We propose that the

  3. Cyclophilins facilitate dissociation of the human papillomavirus type 16 capsid protein L1 from the L2/DNA complex following virus entry.

    Science.gov (United States)

    Bienkowska-Haba, Malgorzata; Williams, Carlyn; Kim, Seong Man; Garcea, Robert L; Sapp, Martin

    2012-09-01

    Human papillomaviruses (HPV) are composed of the major and minor capsid proteins, L1 and L2, that encapsidate a chromatinized, circular double-stranded DNA genome. At the outset of infection, the interaction of HPV type 16 (HPV16) (pseudo)virions with heparan sulfate proteoglycans triggers a conformational change in L2 that is facilitated by the host cell chaperone cyclophilin B (CyPB). This conformational change results in exposure of the L2 N terminus, which is required for infectious internalization. Following internalization, L2 facilitates egress of the viral genome from acidified endosomes, and the L2/DNA complex accumulates at PML nuclear bodies. We recently described a mutant virus that bypasses the requirement for cell surface CyPB but remains sensitive to cyclosporine for infection, indicating an additional role for CyP following endocytic uptake of virions. We now report that the L1 protein dissociates from the L2/DNA complex following infectious internalization. Inhibition and small interfering RNA (siRNA)-mediated knockdown of CyPs blocked dissociation of L1 from the L2/DNA complex. In vitro, purified CyPs facilitated the dissociation of L1 pentamers from recombinant HPV11 L1/L2 complexes in a pH-dependent manner. Furthermore, CyPs released L1 capsomeres from partially disassembled HPV16 pseudovirions at slightly acidic pH. Taken together, these data suggest that CyPs mediate the dissociation of HPV L1 and L2 capsid proteins following acidification of endocytic vesicles.

  4. Ultrastructural characterization of the meiotic prophase. A tool in the assessment of radiation damage in man

    Energy Technology Data Exchange (ETDEWEB)

    Holm, P.B.; Rasmussen, S.W.; von Wettstein, D. (Carlsberg Lab., Copenhagen (Denmark). Dept. of Physiology)

    1982-01-01

    The three-dimensional reconstruction of meiotic nuclei from serial sections micrographed in the electron microscope has provided information about man and several other organisms that is not obtainable by light microscopy or biochemical analysis. At zygotene, the previously unpaired chromosomes align and form synaptonemal complexes between homologous chromosome segments either by progressive initiation from the telomeres or by interstitial recognition. Chromosome and bivalent interlocking at zygotene is a regular phenomenon and occurs at a frequency of 0.7-4.0 per nucleus in samples of meiocytes analyzed from different organisms. This frequency is reduced to 0.1 per nucleus at pachytene. The interlockings are resolved by breakage and precise rejoining of the broken ends. This breakage and rejoining can also occur in the absence of the DNA nicking and repair involved in crossing-over. The synaptonemal complexes combining homologous chromosome segments are stabilized by recombination nodules, after which a second round of synaptonemal complex formation between as yet unpaired or unstably paired chromosome segments occurs, apparently for optimization of bivalent formation. Nonhomologous pairing with the synaptonemal complex can take place in this phase of pachytene.

  5. Meiotic recombination analyses of individual chromosomes in male domestic pigs (Sus scrofa domestica.

    Directory of Open Access Journals (Sweden)

    Nicolas Mary

    Full Text Available For the first time in the domestic pig, meiotic recombination along the 18 porcine autosomes was directly studied by immunolocalization of MLH1 protein. In total, 7,848 synaptonemal complexes from 436 spermatocytes were analyzed, and 13,969 recombination sites were mapped. Individual chromosomes for 113 of the 436 cells (representing 2,034 synaptonemal complexes were identified by immunostaining and fluorescence in situ hybridization (FISH. The average total length of autosomal synaptonemal complexes per cell was 190.3 µm, with 32.0 recombination sites (crossovers, on average, per cell. The number of crossovers and the lengths of the autosomal synaptonemal complexes showed significant intra- (i.e. between cells and inter-individual variations. The distributions of recombination sites within each chromosomal category were similar: crossovers in metacentric and submetacentric chromosomes were concentrated in the telomeric regions of the p- and q-arms, whereas two hotspots were located near the centromere and in the telomeric region of acrocentrics. Lack of MLH1 foci was mainly observed in the smaller chromosomes, particularly chromosome 18 (SSC18 and the sex chromosomes. All autosomes displayed positive interference, with a large variability between the chromosomes.

  6. Ultrastructural aspects of spermatogenesis, testes, and vas deferens in the parthenogenetic tapeworm Atractolytocestus huronensis Anthony, 1958 (Cestoda: Caryophyllidea), a carp parasite from Slovakia

    Czech Academy of Sciences Publication Activity Database

    Bruňanská, M.; Nebesářová, Jana; Oros, M.

    2011-01-01

    Roč. 108, č. 1 (2011), 61-68 ISSN 0932-0113 Institutional research plan: CEZ:AV0Z60220518 Keywords : GLARIDACRIS-CATOSTOMI * SYNAPTONEMAL COMPLEX * REPRODUCTIVE DUCTS * COMMON CARP * SPERMATOZOA * PLATYHELMINTHES * VITELLOGENESIS * EVOLUTION * TRIPLOIDY * CESTOIDEA Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.149, year: 2011

  7. Carney complex (CNC

    Directory of Open Access Journals (Sweden)

    Bertherat Jérôme

    2006-06-01

    Full Text Available Abstract The Carney complex (CNC is a dominantly inherited syndrome characterized by spotty skin pigmentation, endocrine overactivity and myxomas. Skin pigmentation anomalies include lentigines and blue naevi. The most common endocrine gland manifestations are acromegaly, thyroid and testicular tumors, and adrenocorticotropic hormone (ACTH-independent Cushing's syndrome due to primary pigmented nodular adrenocortical disease (PPNAD. PPNAD, a rare cause of Cushing's syndrome, is due to primary bilateral adrenal defect that can be also observed in some patients without other CNC manifestations or familial history of the disease. Myxomas can be observed in the heart, skin and breast. Cardiac myxomas can develop in any cardiac chamber and may be multiple. One of the putative CNC genes located on 17q22-24, (PRKAR1A, has been identified to encode the regulatory subunit (R1A of protein kinase A. Heterozygous inactivating mutations of PRKAR1A were reported initially in 45 to 65 % of CNC index cases, and may be present in about 80 % of the CNC families presenting mainly with Cushing's syndrome. PRKAR1A is a key component of the cAMP signaling pathway that has been implicated in endocrine tumorigenesis and could, at least partly, function as a tumor suppressor gene. Genetic analysis should be proposed to all CNC index cases. Patients with CNC or with a genetic predisposition to CNC should have regular screening for manifestations of the disease. Clinical work-up for all the manifestations of CNC should be performed at least once a year in all patients and should start in infancy. Cardiac myxomas require surgical removal. Treatment of the other manifestations of CNC should be discussed and may include follow-up, surgery, or medical treatment depending on the location of the tumor, its size, the existence of clinical signs of tumor mass or hormonal excess, and the suspicion of malignancy. Bilateral adrenalectomy is the most common treatment for Cushing

  8. Carney complex (CNC).

    Science.gov (United States)

    Bertherat, Jérôme

    2006-06-06

    The Carney complex (CNC) is a dominantly inherited syndrome characterized by spotty skin pigmentation, endocrine overactivity and myxomas. Skin pigmentation anomalies include lentigines and blue naevi. The most common endocrine gland manifestations are acromegaly, thyroid and testicular tumors, and adrenocorticotropic hormone (ACTH)-independent Cushing's syndrome due to primary pigmented nodular adrenocortical disease (PPNAD). PPNAD, a rare cause of Cushing's syndrome, is due to primary bilateral adrenal defect that can be also observed in some patients without other CNC manifestations or familial history of the disease. Myxomas can be observed in the heart, skin and breast. Cardiac myxomas can develop in any cardiac chamber and may be multiple. One of the putative CNC genes located on 17q22-24, (PRKAR1A), has been identified to encode the regulatory subunit (R1A) of protein kinase A. Heterozygous inactivating mutations of PRKAR1A were reported initially in 45 to 65% of CNC index cases, and may be present in about 80% of the CNC families presenting mainly with Cushing's syndrome. PRKAR1A is a key component of the cAMP signaling pathway that has been implicated in endocrine tumorigenesis and could, at least partly, function as a tumor suppressor gene. Genetic analysis should be proposed to all CNC index cases. Patients with CNC or with a genetic predisposition to CNC should have regular screening for manifestations of the disease. Clinical work-up for all the manifestations of CNC should be performed at least once a year in all patients and should start in infancy. Cardiac myxomas require surgical removal. Treatment of the other manifestations of CNC should be discussed and may include follow-up, surgery, or medical treatment depending on the location of the tumor, its size, the existence of clinical signs of tumor mass or hormonal excess, and the suspicion of malignancy. Bilateral adrenalectomy is the most common treatment for Cushing's syndrome due to PPNAD.

  9. Complexity Management In Projects Between Rational Momentum And Complex Conditions

    DEFF Research Database (Denmark)

    Mac, Anita; Schlamovitz, Jesper

    2015-01-01

    Abstract: This study takes its departure in a model of complexity, developed by Stacey (1993), to test and discuss its practical benefit as perceived by practicing project managers. Based on a survey, the study finds that complexity is a phenomenon recognized by project managers, and complexity...... management is associated with benefits in the development of tasks and managing stakeholders. It is also associated with some difficulty in terms of an increased need for dialogue and a risk of creating goal ambiguity. Based on the findings, we conclude that classical project management approaches can...... benefit from incorporating complexity management....

  10. Complexity management in projects between rational momentum and complex conditions

    DEFF Research Database (Denmark)

    Mac, Anita; Schlamovitz, Jesper

    This study takes its departure in a model of complexity, developed by Stacey (1993), to test and discuss its practical benefit as perceived by practicing project managers. Based on a survey, the study finds that complexity is a phenomenon recognized by project managers, and complexity management...... is associated with benefits in the development of tasks and managing stakeholders. It is also associated with some difficulty in terms of an increased need for dialogue and a risk of creating goal ambiguity. Based on the findings, we conclude that classical project management approaches can benefit from...... incorporating complexity management....

  11. Physical Complexity and Cognitive Evolution

    Science.gov (United States)

    Jedlicka, Peter

    Our intuition tells us that there is a general trend in the evolution of nature, a trend towards greater complexity. However, there are several definitions of complexity and hence it is difficult to argue for or against the validity of this intuition. Christoph Adami has recently introduced a novel measure called physical complexity that assigns low complexity to both ordered and random systems and high complexity to those in between. Physical complexity measures the amount of information that an organism stores in its genome about the environment in which it evolves. The theory of physical complexity predicts that evolution increases the amount of `knowledge' an organism accumulates about its niche. It might be fruitful to generalize Adami's concept of complexity to the entire evolution (including the evolution of man). Physical complexity fits nicely into the philosophical framework of cognitive biology which considers biological evolution as a progressing process of accumulation of knowledge (as a gradual increase of epistemic complexity). According to this paradigm, evolution is a cognitive `ratchet' that pushes the organisms unidirectionally towards higher complexity. Dynamic environment continually creates problems to be solved. To survive in the environment means to solve the problem, and the solution is an embodied knowledge. Cognitive biology (as well as the theory of physical complexity) uses the concepts of information and entropy and views the evolution from both the information-theoretical and thermodynamical perspective. Concerning humans as conscious beings, it seems necessary to postulate an emergence of a new kind of knowledge - a self-aware and self-referential knowledge. Appearence of selfreflection in evolution indicates that the human brain reached a new qualitative level in the epistemic complexity.

  12. Nuclear disassembly time scales using space time correlations

    Energy Technology Data Exchange (ETDEWEB)

    Durand, D.; Colin, J.; Lecolley, J.F.; Meslin, C.; Aboufirassi, M.; Bougault, R.; Brou, R. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire; Bilwes, B.; Cosmo, F. [Strasbourg-1 Univ., 67 (France); Galin, J. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France); and others

    1996-09-01

    The lifetime, {tau}, with respect to multifragmentation of highly excited nuclei is deduced from the analysis of strongly damped Pb+Au collisions at 29 MeV/u. The method is based on the study of space-time correlations induced by `proximity` effects between fragments emitted by the two primary products of the reaction and gives the time between the re-separation of the two primary products and the subsequent multifragment decay of one partner. (author). 2 refs.

  13. Learning in the "Platform Society": Disassembling an Educational Data Assemblage

    Science.gov (United States)

    Williamson, Ben

    2017-01-01

    Schools are increasingly involved in diverse forms of student data collection. This article provides a sociotechnical survey of a data assemblage used in education. ClassDojo is a commercial platform for tracking students' behaviour data in classrooms and a social media network for connecting teachers, students, and parents. The hybridization of…

  14. Supermassive Black Holes and Their Host Spheroids. I. Disassembling Galaxies

    Science.gov (United States)

    Savorgnan, G. A. D.; Graham, A. W.

    2016-01-01

    Several recent studies have performed galaxy decompositions to investigate correlations between the black hole mass and various properties of the host spheroid, but they have not converged on the same conclusions. This is because their models for the same galaxy were often significantly different and not consistent with each other in terms of fitted components. Using 3.6 μm Spitzer imagery, which is a superb tracer of the stellar mass (superior to the K band), we have performed state-of-the-art multicomponent decompositions for 66 galaxies with directly measured black hole masses. Our sample is the largest to date and, unlike previous studies, contains a large number (17) of spiral galaxies with low black hole masses. We paid careful attention to the image mosaicking, sky subtraction, and masking of contaminating sources. After a scrupulous inspection of the galaxy photometry (through isophotal analysis and unsharp masking) and—for the first time—2D kinematics, we were able to account for spheroids large-scale, intermediate-scale, and nuclear disks bars rings spiral arms halos extended or unresolved nuclear sources; and partially depleted cores. For each individual galaxy, we compared our best-fit model with previous studies, explained the discrepancies, and identified the optimal decomposition. Moreover, we have independently performed one-dimensional (1D) and two-dimensional (2D) decompositions and concluded that, at least when modeling large, nearby galaxies, 1D techniques have more advantages than 2D techniques. Finally, we developed a prescription to estimate the uncertainties on the 1D best-fit parameters for the 66 spheroids that takes into account systematic errors, unlike popular 2D codes that only consider statistical errors.

  15. SUPERMASSIVE BLACK HOLES AND THEIR HOST SPHEROIDS. I. DISASSEMBLING GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Savorgnan, G. A. D.; Graham, A. W., E-mail: gsavorgn@astro.swin.edu.au [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122 (Australia)

    2016-01-15

    Several recent studies have performed galaxy decompositions to investigate correlations between the black hole mass and various properties of the host spheroid, but they have not converged on the same conclusions. This is because their models for the same galaxy were often significantly different and not consistent with each other in terms of fitted components. Using 3.6 μm Spitzer imagery, which is a superb tracer of the stellar mass (superior to the K band), we have performed state-of-the-art multicomponent decompositions for 66 galaxies with directly measured black hole masses. Our sample is the largest to date and, unlike previous studies, contains a large number (17) of spiral galaxies with low black hole masses. We paid careful attention to the image mosaicking, sky subtraction, and masking of contaminating sources. After a scrupulous inspection of the galaxy photometry (through isophotal analysis and unsharp masking) and—for the first time—2D kinematics, we were able to account for spheroids; large-scale, intermediate-scale, and nuclear disks; bars; rings; spiral arms; halos; extended or unresolved nuclear sources; and partially depleted cores. For each individual galaxy, we compared our best-fit model with previous studies, explained the discrepancies, and identified the optimal decomposition. Moreover, we have independently performed one-dimensional (1D) and two-dimensional (2D) decompositions and concluded that, at least when modeling large, nearby galaxies, 1D techniques have more advantages than 2D techniques. Finally, we developed a prescription to estimate the uncertainties on the 1D best-fit parameters for the 66 spheroids that takes into account systematic errors, unlike popular 2D codes that only consider statistical errors.

  16. SUPERMASSIVE BLACK HOLES AND THEIR HOST SPHEROIDS. I. DISASSEMBLING GALAXIES

    International Nuclear Information System (INIS)

    Savorgnan, G. A. D.; Graham, A. W.

    2016-01-01

    Several recent studies have performed galaxy decompositions to investigate correlations between the black hole mass and various properties of the host spheroid, but they have not converged on the same conclusions. This is because their models for the same galaxy were often significantly different and not consistent with each other in terms of fitted components. Using 3.6 μm Spitzer imagery, which is a superb tracer of the stellar mass (superior to the K band), we have performed state-of-the-art multicomponent decompositions for 66 galaxies with directly measured black hole masses. Our sample is the largest to date and, unlike previous studies, contains a large number (17) of spiral galaxies with low black hole masses. We paid careful attention to the image mosaicking, sky subtraction, and masking of contaminating sources. After a scrupulous inspection of the galaxy photometry (through isophotal analysis and unsharp masking) and—for the first time—2D kinematics, we were able to account for spheroids; large-scale, intermediate-scale, and nuclear disks; bars; rings; spiral arms; halos; extended or unresolved nuclear sources; and partially depleted cores. For each individual galaxy, we compared our best-fit model with previous studies, explained the discrepancies, and identified the optimal decomposition. Moreover, we have independently performed one-dimensional (1D) and two-dimensional (2D) decompositions and concluded that, at least when modeling large, nearby galaxies, 1D techniques have more advantages than 2D techniques. Finally, we developed a prescription to estimate the uncertainties on the 1D best-fit parameters for the 66 spheroids that takes into account systematic errors, unlike popular 2D codes that only consider statistical errors

  17. Functional and cosmetic outcome of partial penile disassembly ...

    African Journals Online (AJOL)

    A. Bhat

    2017-07-04

    Jul 4, 2017 ... Technique: Penile de-gloving with mobilization of urethral plate from ventral to dorsal ... BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). ..... Literature search , Clinical studies, Experimental studies, Data.

  18. Will biofilm disassembly agents make it to market?

    Science.gov (United States)

    Romero, Diego; Kolter, Roberto

    2011-07-01

    Nearly 12 years after promising results suggested that antibiofilm agents might be developed into novel therapeutics, there are no such products on the market. In our opinion, the reasons for this have been predominantly economic. Recent developments, however, suggest that there could still be emerging opportunities for the developments of such products. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Energy impacts of recycling disassembly material in residential buildings

    International Nuclear Information System (INIS)

    Gao, Weijun; Ariyama, Takahiro; Ojima, Toshio; Meier, Alan

    2000-01-01

    In order to stop the global warmth due to the CO2 concentration, the energy use should be decreased. The investment of building construction industry in Japan is about 20 percent of GDP. This fraction is much higher than in most developed countries. That results the Japanese building construction industry including residential use consumes about one third of all energy and resources of the entire industrial sectors. In order to save energy as well as resource, the recycle of the building materials should be urgent to be carried out. In this paper, we focus on the potential energy savings with a simple calculated method when the building materials or products are manufactured from recycled materials. We examined three kinds of residential buildings with different construction techniques and estimated the decreased amount of energy consumption and resources resulting from use of recycled materials. The results have shown for most building materials, the energy consumption needed to remake housing materials from recycled materials is lower than that to make new housing materials. The energy consumption of building materials in all case-study housing can be saved by at least 10 percent. At the same time, the resource, measured by mass of building materials (kg) can be decreased by over 50 percent

  20. SP-100 reactor disassembly remote handling test program

    International Nuclear Information System (INIS)

    Wilson, C.E.; Potter, J.D.; Maiden, G.E.; Vader, D.P.

    1991-01-01

    This paper is presented as an overview of the remote handling equipment validation testing, which will be conducted before installation and use in the ground engineering test facility. This equipment will be used to defuel the SP-100 reactor core after removing it from the Test Assembly following nuclear testing. A series of full scale mock-up operational tests will be conducted at a Hanford Site facility to verify equipment design, operation, and capabilities